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  • 1
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    MDPI Publishing
    In: Sensors
    Publication Date: 2018-08-04
    Description: Sensors, Vol. 18, Pages 2538: A New Variational Bayesian Adaptive Extended Kalman Filter for Cooperative Navigation Sensors doi: 10.3390/s18082538 Authors: Sun Zhang Wang Gao To solve the problem of unknown state noises and uncertain measurement noises inherent in underwater cooperative navigation, a new Variational Bayesian (VB)-based Adaptive Extended Kalman Filter (VBAEKF) for master–slave Autonomous Underwater Vehicles (AUV) is proposed in this paper. The Inverse Wishart (IW) distribution is used to model the predicted error covariance and measurement noise covariance matrix. The state, together with the predicted error covariance and measurement noise covariance matrix, can be adaptively estimated based on VB approximation. The performance of the proposed algorithm is demonstrated through a lake trial, which shows the advantage of the proposed algorithm.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 2
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    MDPI Publishing
    In: Sensors
    Publication Date: 2018-08-04
    Description: Sensors, Vol. 18, Pages 2539: Efficient Force Control Learning System for Industrial Robots Based on Variable Impedance Control Sensors doi: 10.3390/s18082539 Authors: Chao Li Zhi Zhang Guihua Xia Xinru Xie Qidan Zhu Learning variable impedance control is a powerful method to improve the performance of force control. However, current methods typically require too many interactions to achieve good performance. Data-inefficiency has limited these methods to learn force-sensitive tasks in real systems. In order to improve the sampling efficiency and decrease the required interactions during the learning process, this paper develops a data-efficient learning variable impedance control method that enables the industrial robots automatically learn to control the contact force in the unstructured environment. To this end, a Gaussian process model is learned as a faithful proxy of the system, which is then used to predict long-term state evolution for internal simulation, allowing for efficient strategy updates. The effects of model bias are reduced effectively by incorporating model uncertainty into long-term planning. Then the impedance profiles are regulated online according to the learned humanlike impedance strategy. In this way, the flexibility and adaptivity of the system could be enhanced. Both simulated and experimental tests have been performed on an industrial manipulator to verify the performance of the proposed method.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 3
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    MDPI Publishing
    Publication Date: 2018-08-04
    Description: Sustainability, Vol. 10, Pages 2751: Mapping Agroecology in Europe. New Developments and Applications Sustainability doi: 10.3390/su10082751 Authors: Alexander Wezel Stéphane Bellon Agroecology has gradually developed in recent decades, but has only recently been more strongly promoted by different movements, organizations, institutions, farmer groups, and scholars.[...]
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 4
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    MDPI Publishing
    In: Sensors
    Publication Date: 2018-08-04
    Description: Sensors, Vol. 18, Pages 2537: An Electrochemiluminescence Sensor Based on Nafion/Magnetic Fe3O4 Nanocrystals Modified Electrode for the Determination of Bisphenol A in Environmental Water Samples Sensors doi: 10.3390/s18082537 Authors: Jiye Chai Xinru Yu Jian Zhao Aili Sun Xizhi Shi Dexiang Li The well-dispersive and superparamagnetic Fe3O4-nanocrystals (Fe3O4-NCs) which could significantly enhance the anodic electrochemiluminescence (ECL) behavior of luminol, were synthesized in this study. Compared to ZnS, ZnSe, CdS and CdTe nanoparticles, the strongest anodic ECL signals were obtained at +1.6 V on the Fe3O4-NCs coated glassy carbon electrode. The ECL spectra revealed that the strong ECL resonance energy transfer occurred between luminol and Fe3O4-NCs. Furthermore, under the optimized ECL experimental conditions, such as the amount of Fe3O4-NCs, the concentration of luminol and the pH of supporting electrolyte, BPA exhibited a stronger distinct ECL quenching effect than its structural analogs and a highly selective and sensitive ECL sensor for the determination of bisphenol A (BPA) was developed based on the Fe3O4-NCs. A good linear relationship was found between the ECL intensity and the increased BPA concentration within 0.01–5.0 mg/L, with a correlation coefficient of 0.9972. The detection limit was 0.66 × 10−3 mg/L. Good recoveries between 96.0% and 105.0% with a relative standard deviation of less than 4.8% were obtained in real water samples. The proposed ECL sensor can be successfully employed to BPA detection in environmental aqueous samples.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 5
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    MDPI Publishing
    Publication Date: 2018-08-04
    Description: Sustainability, Vol. 10, Pages 2750: The Santa Barbara Oil Spill and Its Effect on United States Environmental Policy Sustainability doi: 10.3390/su10082750 Authors: Teresa Sabol Spezio The National Environmental Policy Act of 1970 (NEPA) paved the way for comprehensive federal environmental policy in the United States. NEPA has successfully allowed citizens and others to become active participants in the environmental decision-making process for federal infrastructure projects throughout the evolution of environmental policy in the United States. Its efficacy was enhanced because of an oil spill off the Santa Barbara coast in January 1969. This disaster gave the framers of NEPA an example of the consequences of the lack of environmental policy in federal decision making. Using their original proactive approach along with the reactive response to the spill, they created a policy that has can be seen as a foundation for 21st century sustainability and resilience programs.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 6
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    MDPI Publishing
    Publication Date: 2018-08-04
    Description: Sustainability, Vol. 10, Pages 2748: A Cradle to Handover Life Cycle Assessment of External Walls: Choice of Materials and Prognosis of Elements Sustainability doi: 10.3390/su10082748 Authors: Diana Carolina Gámez-García José Manuel Gómez-Soberón Ramón Corral-Higuera Héctor Saldaña-Márquez María Consolación Gómez-Soberón Susana Paola Arredondo-Rea This research focuses on a comparison of 20 external wall systems that are conventionally used in Spanish residential buildings, from a perspective based on the product and construction process stages of the life cycle assessment. The primary objective is to provide data that allow knowing the environmental behavior of walls built with materials and practices conventionally. This type of analysis will enable promoting the creation of regulations that encourage the use of combinations of materials that generate the most environmentally suitable result, and in turn, contribute to the strengthening of the embodied stages study of buildings and their elements. The results indicate that the greatest impact arises in the product stage (90.9%), followed by the transport stage (8.9%) and the construction process stage (<1%). Strategies (such as the use of large-format pieces and the controlled increase in thickness of the thermal insulation) can contribute to reducing the environmental impact; on the contrary, practices such as the use of small-format pieces and laminated plasterboard can increase the environmental burden. The prediction of the environmental behavior (simulation equation) allows these possible impacts to be studied in a fast and simplified way.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 7
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    MDPI Publishing
    Publication Date: 2018-08-04
    Description: Sustainability, Vol. 10, Pages 2749: Morphological Precision Assessment of Reconstructed Surface Models for a Coral Atoll Lagoon Sustainability doi: 10.3390/su10082749 Authors: Qi Wang Fenzhen Su Yu Zhang Huiping Jiang Fei Cheng In addition to remote-sensing monitoring, reconstructing morphologic surface models through interpolation is an effective means to reflect the geomorphological evolution, especially for the lagoons of coral atolls, which are underwater. However, which interpolation method is optimal for lagoon geomorphological reconstruction and how to assess the morphological precision have been unclear. To address the aforementioned problems, this study proposed a morphological precision index system including the root mean square error (RMSE) of the elevation, the change rate of the local slope shape (CRLSS), and the change rate of the local slope aspect (CRLSA), and introduced the spatial appraisal and valuation approach of environment and ecosystems (SAVEE). In detail, ordinary kriging (OK), inverse distance weighting (IDW), radial basis function (RBF), and local polynomial interpolation (LPI) were used to reconstruct the lagoon surface models of a typical coral atoll in South China Sea and the morphological precision of them were assessed, respectively. The results are as follows: (i) OK, IDW, and RBF exhibit the best performance in terms of RMSE (0.3584 m), CRLSS (51.43%), and CRLSA (43.29%), respectively, while with insufficiently robust when considering all three aspects; (ii) IDW, LPI, and RBF are suitable for lagoon slopes, lagoon bottoms, and patch reefs, respectively; (iii) The geomorphic decomposition scale is an important factor that affects the precision of geomorphologic reconstructions; and, (iv) This system and evaluation approach can more comprehensively consider the differences in multiple precision indices.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 8
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    MDPI Publishing
    In: Sensors
    Publication Date: 2018-08-07
    Description: Sensors, Vol. 18, Pages 2574: Modeling and Control of a Micro AUV: Objects Follower Approach Sensors doi: 10.3390/s18082574 Authors: Jesus Arturo Monroy-Anieva Cyril Rouviere Eduardo Campos-Mercado Tomas Salgado-Jimenez Luis Govinda Garcia-Valdovinos This work describes the modeling, control and development of a low cost Micro Autonomous Underwater Vehicle (μ-AUV), named AR2D2. The main objective of this work is to make the vehicle to detect and follow an object with defined color by means of the readings of a depth sensor and the information provided by an artificial vision system. A nonlinear PD (Proportional-Derivative) controller is implemented on the vehicle in order to stabilize the heave and surge movements. A formal stability proof of the closed-loop system using Lyapunov’s theory is given. Furthermore, the performance of the μ-AUV is validated through numerical simulations in MatLab and real-time experiments.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 9
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    MDPI Publishing
    In: Sensors
    Publication Date: 2018-08-07
    Description: Sensors, Vol. 18, Pages 2573: Screening Method for Anti-Colon Cancer Drugs Using Two Sensor Cell Lines with Human β4-Galactosyltransferase 4 Gene Promoters Sensors doi: 10.3390/s18082573 Authors: Naomichi Fukushima Atena Sugiyama Takeshi Sato The increased expression of β4-galactosyltransferase (β4GalT) 4 is closely associated with poor prognosis of colon cancer. Recently, we showed that the expression of the β4GalT4 gene is regulated by the 0.17 kb core promoter region containing one binding site for Specificity protein 1 (Sp1). To develop a screening method for anti-colon cancer drugs, two sensor cell lines having the luciferase gene under the control of two β4GalT4 gene promoters that differed in length were established from SW480 human colon cancer cells. The hGT4-0.17-sensor cells possessed the luciferase reporter driven by the 0.17 kb promoter, while the hGT4-0.3-sensor cells possessed the luciferase reporter driven by the 0.3 kb promoter containing one binding site each for colon cancer-related transcription factors including activator protein 2, E2F, caudal-related homeobox transcription factors, and Runt-related transcription factors besides Sp1. Upon treatment with mitogen-activated protein kinase signaling inhibitor U0126, the promoter activities of the hGT4-0.3-sensor cells decreased significantly, while those of the hGT4-0.17-sensor cells remained unchanged. These results suggest that the responsiveness to U0126 differs between two sensor cell lines due to the different regulation of the luciferase reporters. This study provides the screening method for anti-colon cancer drugs by the combination of two sensor cell lines.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 10
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    MDPI Publishing
    In: Sensors
    Publication Date: 2018-08-07
    Description: Sensors, Vol. 18, Pages 2571: Towards a Meaningful 3D Map Using a 3D Lidar and a Camera Sensors doi: 10.3390/s18082571 Authors: Jongmin Jeong Tae Sung Yoon Jin Bae Park Semantic 3D maps are required for various applications including robot navigation and surveying, and their importance has significantly increased. Generally, existing studies on semantic mapping were camera-based approaches that could not be operated in large-scale environments owing to their computational burden. Recently, a method of combining a 3D Lidar with a camera was introduced to address this problem, and a 3D Lidar and a camera were also utilized for semantic 3D mapping. In this study, our algorithm consists of semantic mapping and map refinement. In the semantic mapping, a GPS and an IMU are integrated to estimate the odometry of the system, and subsequently, the point clouds measured from a 3D Lidar are registered by using this information. Furthermore, we use the latest CNN-based semantic segmentation to obtain semantic information on the surrounding environment. To integrate the point cloud with semantic information, we developed incremental semantic labeling including coordinate alignment, error minimization, and semantic information fusion. Additionally, to improve the quality of the generated semantic map, the map refinement is processed in a batch. It enhances the spatial distribution of labels and removes traces produced by moving vehicles effectively. We conduct experiments on challenging sequences to demonstrate that our algorithm outperforms state-of-the-art methods in terms of accuracy and intersection over union.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 11
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    MDPI Publishing
    In: Sensors
    Publication Date: 2018-08-07
    Description: Sensors, Vol. 18, Pages 2569: An X-band Bi-Directional Transmit/Receive Module for a Phased Array System in 65-nm CMOS Sensors doi: 10.3390/s18082569 Authors: Van-Viet Nguyen Hyohyun Nam Young Joe Choe Bok-Hyung Lee Jung-Dong Park We present an X-band bi-directional transmit/receive module (TRM) for a phased array system utilized in radar-based sensor systems. The proposed module, comprising a 6-bit phase shifter, a 6-bit digital step attenuator, and bi-directional gain amplifiers, is fabricated using 65-nm CMOS technology. By constructing passive networks in the phase-shifter and the variable attenuator, the implemented TRM provides amplitude and phase control with 360° phase coverage and 5.625° as the minimum step size while the attenuation range varies from 0 to 31.5 dB with a step size of 0.5 dB. The fabricated T/R module in all of the phase shift states had RMS phase errors of less than 4° and an RMS amplitude error of less than 0.93 dB at 9–11 GHz. The output 1dB gain compression point (OP1dB) of the chip was 5.13 dBm at 10 GHz. The circuit occupies 3.92 × 2.44 mm2 of the chip area and consumes 170 mW of DC power.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 12
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    MDPI Publishing
    In: Sensors
    Publication Date: 2018-08-07
    Description: Sensors, Vol. 18, Pages 2567: DIFTOS: A Distributed Infrastructure-Free Traffic Optimization System Based on Vehicular Ad Hoc Networks for Urban Environments Sensors doi: 10.3390/s18082567 Authors: Weidong Zhang Nyothiri Aung Sahraoui Dhelim Yibo Ai Aiming to alleviate traffic congestion, many congestion avoidance and traffic optimization systems have been proposed recently. However, most of them suffer from three main problems. Firstly scalability: they rely on a centralized server, which has to perform intensive communication and computational tasks. Secondly unpredictability: they use smartphones and other sensors to detect the congested roads and warn upcoming vehicles accordingly. In other words, they are used to solve the problem rather than avoiding it. Lastly, infrastructure dependency: they assume the presence of pre-installed infrastructures such as roadside unit (RSU) or cellular 3G/4G networks. Motivated by the above-mentioned reasons, in this paper, we proposed a fully distributed and infrastructure-less congestion avoidance and traffic optimization system for VANET (Vehicular Ad-hoc Networks) in urban environments named DIFTOS (Distributed Infrastructure-Free Traffic Optimization System), in which the city map is divided into a hierarchy of servers. The vehicles that are located in the busy road intersections play the role of servers, thus DIFTOS does not rely on any centralized server and does not need internet connectivity or RSU or any kind of infrastructure. As far as we know, in the literature of congestion avoidance using VANET, DIFTOS is the first completely infrastructure-free congestion avoidance system. The effectiveness and scalability of DIFTOS have been proved by simulation under different traffic conditions.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 13
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    MDPI Publishing
    Publication Date: 2018-08-07
    Description: Sustainability, Vol. 10, Pages 2784: Comment on Apiors, E.K.; Suzuki, A. Mobile Money, Individuals’ Payments, Remittances, and Investments: Evidence from the Ashanti Region, Ghana. Sustainability 2018, 10, 1409 Sustainability doi: 10.3390/su10082784 Authors: Leo Van Hove Using primary, individual-level survey data for Ghana, Apiors and Suzuki find, among other things, that mobile money use is not dependent on financial status and that mobile money users save more. This note argues that both conclusions have validity issues.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 14
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    MDPI Publishing
    Publication Date: 2018-08-07
    Description: Sustainability, Vol. 10, Pages 2781: Pathways for Sustainable Supply Chain Performance—Evidence from a Developing Country, Malaysia Sustainability doi: 10.3390/su10082781 Authors: Kai-Chong Thong Wai-Peng Wong Malaysia has recently started to adopt sustainable business best practices to benefit companies, environment and stakeholders. Therefore, this study demonstrates pathways to sustainable supply chain triple bottom line performance derived from linkages of institutional pressures (IP) and organizational identity (OI) to environment and social sustainable practices. It shows that the superordinate goal of sustainable supply chain management is met in spite of unyielding external pressures and desirable OI driving the unequivocal environmental and responsible social practices of firms. A survey approach was adopted to gather the data required for this study. A total of 118 completed questionnaires were received from respondents, who were managers and senior executives in supply chain management (SCM) in Malaysia. The data were analyzed using structural equation modeling with partial least squares (PLS-SEM) version 3.0. Our findings showed that all hypothesized relationships are significant except both process- and market-based social practices could not directly impact economic performance. This is in sharp contrast to environmental practices. However, the significant linkage between social practices and social performance is a pathway for the former to economic performance. Therefore, the economic benefits derived from social practices are salvaged through its performance outcomes. The novel and useful impact of institutional pressures on sustainable supply chain practices are also unearthed.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 15
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    MDPI Publishing
    Publication Date: 2018-08-07
    Description: Sustainability, Vol. 10, Pages 2780: Dynamic Decomposition of Factors Influencing the Export Growth of China’s Wood Forest Products Sustainability doi: 10.3390/su10082780 Authors: Xuping Cao Shuai Yang Xiangmeng Huang Juxi Tong Wood forest products (WFPs) are globally important environmental products, with economic, ecological, and renewable characteristics. China is the world’s largest WFP exporter. However, many factors, such as the downturn of traditional major export markets and the rise of the price of production factors, have generated great challenges and uncertainties for China’s WFP export market. This study improves the product scope of WFPs. The category of WFPs has been expanded to 14 categories and 30 sub-categories, which is more detailed and more developed than in previous literature. Based on the United Nations’ Comtrade Database (COMTRADE), this paper uses the revised constant market share (CMS) model to measure and analyze empirically the factors affecting the export growth of China’s WFPs from the perspective of market, structure, and competitiveness. It is found that (1) the competitive effect exerts the biggest influence on export growth, followed by market size effects, with the effects of market distribution and product structure both being small; (2) wooden furniture, wooden products, plywood, paper, and its products play a main role in enhancing the competitive effect in China’s WFPs; and (3) China’s WFPs have a strong market competitiveness in other markets such as the USA, China Hong Kong, United Kingdom, Japan, Australia, Malaysia, and Singapore. Therefore, it is crucial for China’s WFP market to improve its product structure effects and market distribution effects in order for it to participate in international competition. On the other hand, considering that China’s exports of WFPs mainly consist of resource- and labor-intensive products, the improvement of standards such as the technology level, environmental protection and sustainable development, must not be ignored.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 16
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    MDPI Publishing
    Publication Date: 2018-08-07
    Description: Sustainability, Vol. 10, Pages 2779: Exploring the Research Trend of Smart Factory with Topic Modeling Sustainability doi: 10.3390/su10082779 Authors: Hyun-Lim Yang Tai-Woo Chang Yerim Choi Growing competition among manufacturing businesses and the advent of the Fourth Industrial Revolution has meant that many countries are conducting various research projects to understand how to introduce and populate smart factories. Smart factories are expected to provide a way of solving the manufacturing industries’ complex problems, to take a role in breakthroughs in factories and to carry on a sustainable business. Smart factories are currently in the introduction stage, so we should follow up on the majorities and check their tendencies. However, smart-factory research is an interdisciplinary field that should be studied by researchers with diverse backgrounds in various domains. Thus, studying the past and present overall research trends of smart factory studies is required for their successful introduction and sustainable research. In this study, we explored the research trends of smart factories in both international and specifically Korean research, as an example of a nation case, to determine the major research directions. We determined trends using latent semantic analysis, which is a known topic-modeling technique, and analyzed the trends with regression-based methods. As a result, we could read the clear trends by analyzing existing studies related to smart factories. In addition, it is possible to compare research trends in Korea and international research trends for the commonly appeared topics, such as ‘ICT’ (Information and Communications Technology) and ‘R&D (Research and Development)/Technology Innovation’. We expect that the quantitative analysis results and suggestions presented in this study can be used to formulate strategies for the future diffusion of smart factories.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 17
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    MDPI Publishing
    Publication Date: 2018-08-07
    Description: Sustainability, Vol. 10, Pages 2776: Comparative Analysis of Biological Effects Induced on Different Cell Types by Magnetic Fields with Magnetic Flux Densities in the Range of 1–60 mT and Frequencies up to 50 Hz Sustainability doi: 10.3390/su10082776 Authors: Cristian Vergallo Luciana Dini Moderate static magnetic fields (SMFs) are generated from sources such as new-generation electric trams and trains, electric arc welding, and magnetic resonance imaging (MRI) devices, as well as during the industrial production of aluminium, while extremely low frequency pulsed magnetic fields (ELF-PMFs) are produced by house power installations, household appliances, and high voltages transmission lines. Moderate SMFs and ELF-PMFs with magnetic flux densities (B) in the range of 1–60 mT and frequencies (f) up to 50 Hz are common MF exposure sources for the population. Even though humans are continually exposed to these MFs, to date no definitive endpoint has been drawn about their safety. In this review, the state of knowledge about the biological effects induced by these MFs on different cell types will be addressed. In our own observation, the putative modulation of Ca2+/H+ and Na+/H+ plasma membrane antiporters of human peripheral blood lymphocytes (PBLs) was found to occur after a 24 h exposure to a 6 mT SMF, and the bystander effect observed on U937 cells cultivated for up to 6 h in the conditioned medium harvested from human PBLs previously exposed for 24 h to the same MF (secondary necrosis induction) will be also herein discussed.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 18
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    MDPI Publishing
    Publication Date: 2018-08-07
    Description: Sustainability, Vol. 10, Pages 2777: Sustainability Assurance in Socially-Sensitive Sectors: A Worldwide Analysis of the Financial Services Industry Sustainability doi: 10.3390/su10082777 Authors: Elies Seguí-Mas Fernando Polo-Garrido Helena María Bollas-Araya Sustainability reporting and assurance have considerably increased in the last decades. Among different sectors, ‘sensitive sectors’ attracted the attention of many academics. However, most of research works were focused only on ‘environmentally-sensitive sectors’. Therefore, after the loss of trust caused by the lack of transparency due to the crisis, ‘socially-sensitive sectors’ as financial services sector needs to strengthen users’ confidence in the credibility of their reported activities. The aim of this paper is to assess assurance practices worldwide in one of the main ‘socially-sensitive sectors’: the financial services sector. We study what factors are associated with adoption of assurance and choice of assurance provider, and whether assurance statements differ across providers. Our results reveal that, compared to the global context, companies operating in the financial services sector are more likely to adopt assurance and to choose accountants as assurance providers. Our findings show that adoption of assurance depends on company size. We also found that companies using the financial services sector supplement are more prone to adopt assurance. Our results also evidence that choice of assurance provider depends on the country and listing status Finally, our research shows a great variability in assurance statements across providers.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 19
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    MDPI Publishing
    Publication Date: 2018-08-07
    Description: Sustainability, Vol. 10, Pages 2773: Measuring and Spatio-Temporal Evolution for the Late-Development Advantage in China’s Provinces Sustainability doi: 10.3390/su10082773 Authors: Fei Ma Fei Liu Qipeng Sun Wenlin Wang Xiaodan Li The coordinated development of regional economies is a major economic goal of many countries around the world. To that end, China has actively carried out a series of strategies to expedite the development of its late-developing regions. This study explores the issues raised by this coordinated development from the perspective of late-development advantages, which refer to a region’s late-development advantages compared with the early-developing regions in the country. The 15 indicators applied for evaluating the late-development advantages fall into five categories including capital, technology, industrial structure, institutions and human resources. Then, the model of entropy-weighted technique for order preference by similarity to an ideal solution (EW-TOPSIS) is applied to evaluate the late-development advantages of China’s provinces. Following this, ArcGIS and GeoDa are used to analyze the spatio-temporal evolution pattern of the late-development advantages of China’s provinces, and to compare the spatio-temporal effect of these advantages between the provinces. The results show that the overall late-development advantages of China’s provinces had a downward trend from 2006 to 2015, with the Eastern Region falling by 8.07%, the Central Region falling by 14.37% and the Western Region falling by 8.05%, indicating that the development gap between China’s Eastern and Western Regions is still large. The temporal effect analysis shows the temporal autocorrelation changes from positive status to negative status with the increase of lagging order, which means the trend of late-development advantage will reverse over time. The spatial effect analysis shows there were only significant Low-Low and Low-High aggregation in 2006 and 2010, but significant High-High and High-Low aggregations emerge in 2012 and 2015, implying that the development environment has effectively promoted the use of the provincial late-development advantage. The research results could provide theoretical basis for the policy making of the accelerating development of late-developing regions in China.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 20
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    MDPI Publishing
    Publication Date: 2018-08-07
    Description: Sustainability, Vol. 10, Pages 2768: Evaluating Greenhouse Tomato and Pepper Input Efficiency Use in Kosovo Sustainability doi: 10.3390/su10082768 Authors: Blend Frangu Jennie Sheerin Popp Michael Thomsen Arben Musliu Determinants of vegetable production input efficiency affect a Kosovar farmer’s decision to contribute to the agricultural sector. This study evaluates the input efficiency of greenhouse tomato and pepper farms in Kosovo. Using data collected from farm surveys, we conducted an input-oriented data envelopment analysis (DEA) to empirically assess input efficiency. Second, linear regression analysis was used to investigate what farm variables predict greenhouse tomato and pepper technical efficiency (TE). The DEA results indicated that, among the seven regions in Kosovo, Prizren emerged as the most efficient greenhouse tomato-producing region with a mean efficiency of 0.83 (on a scale of 0 to 1.00). Prishtina followed with a mean efficiency of 0.80. In the production of greenhouse peppers, Prishtina was the most efficient region with a mean efficiency of 0.99. Ferizaj followed with a mean efficiency of 0.93. Conclusions about farm characteristics that explain differences in efficiency were sensitive to model specification. Nevertheless, depending on the structural and operational characteristics of the greenhouse tomato and pepper farms, there is an opportunity for the technically inefficient farms and regions to improve their use of inputs.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 21
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    MDPI Publishing
    Publication Date: 2018-08-07
    Description: Sustainability, Vol. 10, Pages 2766: Outsourcing Performance in Hotels: Evaluating Partnership Quality Sustainability doi: 10.3390/su10082766 Authors: Tomás F. Espino-Rodríguez Juan Carlos Ramírez-Fierro In this study, a research model investigates the influence of various factors of the outsourcing relationship that condition partnership quality. The factors considered as determinants of outsourcing partnership quality are the strategic benefits and the degree of outsourcing. Partnership quality is based on relationships governed by confidence, commitment, business understanding, shared benefits and risks, and conflict resolution. The model also studies the influence of the partnership quality between the supplier and the hotel on the outsourcing performance, considered from the financial, strategic, and overall satisfaction perspectives. To test the hypotheses, this study used the Partial Least Squares (PLS) technique with a sample of managers in an important tourist destination in Spain. The results of the study confirm that the strategic benefits and the degree of outsourcing perceived by the manager are determinant factors of the quality of the outsourcing partnership. In addition, they show that closer relationships with service suppliers imply greater outsourcing performance. Finally, implications for theory and practice are discussed.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 22
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    MDPI Publishing
    Publication Date: 2018-08-07
    Description: Symmetry, Vol. 10, Pages 323: Temperature-Dependent s± ↔ s++ Transitions in the Multiband Model for Fe-Based Superconductors with Impurities Symmetry doi: 10.3390/sym10080323 Authors: V. A. Shestakov M. M. Korshunov O. V. Dolgov We study the dependence of the superconducting gaps on both the disorder and the temperature within the two-band model for iron-based materials. In the clean limit, the system is in the s± state with sign-changing gaps. Scattering by nonmagnetic impurities leads to the change of the sign of the smaller gap, resulting in a transition from the s± to the s++ state with the sign-preserving gaps. We show here that the transition is temperature-dependent. Thus, there is a line of s±→s++ transition in the temperature–disorder phase diagram. There is a narrow range of impurity scattering rates, where the disorder-induced s±→s++ transition occurs at low temperatures, but then the low-temperature s++ state transforms back to the s± state at higher temperatures. With increasing impurity scattering rate, the temperature of such s++→s± transition shifts to the critical temperature Tc, and only the s++ state is left for higher amounts of disorder.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 23
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    MDPI Publishing
    Publication Date: 2018-09-06
    Description: IJERPH, Vol. 15, Pages 1935: Does Information Pattern Affect Risk Perception of Food Safety? A National Survey in China International Journal of Environmental Research and Public Health doi: 10.3390/ijerph15091935 Authors: Guanghua Han Yihong Liu Examining the variances in the assessments of risk, as perceived by residents, facilitates the development of appropriate risk information communication strategies. This paper aims to identify the effects of information source patterns on perceived food safety risks based on demographic factors. A national survey was conducted to examine, by means of multiple regression analysis, the relationship between the public’s perceived risks, demographic factors and information access. The study finds that residents’ preferences for information sources have been empirically proven to significantly affect their perceptions of food safety. We also find that more educated young urban dwellers, as well as those without cohabitation experience, tend to perceive a higher level of risk with respect to food safety. In contrast to our expectations, gender, family income and family size are not significantly correlated with the perception of food safety risk. The findings help to explain residents’ attitudes toward food safety administration and reactions to food hazards in the Chinese context. It is recommended that the governing authorities strengthen their communication capacities using modern communication media and make full use of traditional and face-to-face communications with respect to regulations.
    Print ISSN: 1661-7827
    Electronic ISSN: 1660-4601
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Medicine
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  • 24
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    MDPI Publishing
    Publication Date: 2018-09-06
    Description: IJERPH, Vol. 15, Pages 1934: Pregnancy Related Health Care Needs in Refugees—A Current Three Center Experience in Europe International Journal of Environmental Research and Public Health doi: 10.3390/ijerph15091934 Authors: Christian Dopfer Annabelle Vakilzadeh Christine Happle Evelyn Kleinert Frank Müller Diana Ernst Reinhold E. Schmidt Georg M. N. Behrens Sonja Merkesdal Martin Wetzke Alexandra Jablonka Background: Immigration into Europe has reached an all-time high. Provision of coordinated healthcare, especially to refugee women that are at increased risk for adverse pregnancy outcomes, is a challenge for receiving health care systems. Methods: We assessed pregnancy rates and associated primary healthcare needs in three refugee cohorts in Northern Germany during the current crisis. Results: Out of n = 2911 refugees, 18.0% were women of reproductive age, and 9.1% of these were pregnant. Pregnancy was associated with a significant, 3.7-fold increase in primary health care utilization. Language barrier and cultural customs impeded healthcare to some refugee pregnant women. The most common complaints were demand for pregnancy checkup without specific symptoms (48.6%), followed by abdominal pain or urinary tract infections (in 11.4% of cases each). In 4.2% of pregnancies, severe complications such as syphilis or suicide attempts occurred. Discussion: We present data on pregnancy rates and pregnancy associated medical need in three current refugee cohorts upon arrival in Germany. Healthcare providers should be particularly aware of the requirements of pregnant migrants and should adapt primary caretaking strategies accordingly.
    Print ISSN: 1661-7827
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    Topics: Energy, Environment Protection, Nuclear Power Engineering , Medicine
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  • 25
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    MDPI Publishing
    Publication Date: 2018-09-06
    Description: IJERPH, Vol. 15, Pages 1932: Reducing the Future Risk of Trauma: On the Integration of Global Disaster Policy within Specific Health Domains and Established Fields of Practice International Journal of Environmental Research and Public Health doi: 10.3390/ijerph15091932 Authors: Lennart Reifels The global increase in the frequency and severity of natural hazards and extreme climatic events necessitates more efficient global and national strategies to reduce the likelihood and impact of traumatic consequences for disaster-affected populations. The recent inclusion of mental health in the Sendai Framework for Disaster Risk Reduction marks a pivotal point in the recognition of the significant burden of disasters on mental health, and a global commitment to reducing its impacts. Nevertheless, effective agreement implementation and efforts to reduce disaster mental health risks are facing significant challenges. These include a lack of clarity about the conceptual interlinkages and place of disaster risk reduction principles within the field of disaster mental health, which is traditionally marked by a prevailing recovery orientation, and the need for effective translation into disaster mental health policy and practice. Therefore, this study drew on data from interviews with European disaster mental health and risk reduction experts in order to appraise the merit and implications of a global disaster risk reduction policy for advancing population mental health in the context of disaster. Study findings outline existing opportunities, challenges, and key strategies for the integration of disaster risk reduction within disaster mental health policy and practice.
    Print ISSN: 1661-7827
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    Topics: Energy, Environment Protection, Nuclear Power Engineering , Medicine
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  • 26
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    MDPI Publishing
    Publication Date: 2018-09-06
    Description: IJERPH, Vol. 15, Pages 1931: The Association between US Adolescents’ Weight Status, Weight Perception, Weight Satisfaction, and Their Physical Activity and Dietary Behaviors International Journal of Environmental Research and Public Health doi: 10.3390/ijerph15091931 Authors: Furong Xu Steven A. Cohen Mary L. Greaney Geoffrey W. Greene Background: It remain unclear that the association between weight status, weight perception, weight satisfaction and the clustering of physical activity (PA) and dietary behaviors in adolescents. Method: A cross-sectional analysis of National Health and Nutrition Examination Survey and the US Department of Agriculture’s Food Patterns Equivalents 2007–2014 data from adolescents aged 12–17 years (n = 2965) was conducted. Multivariable logistic regression models adjusted for demographic characteristics examined the association between weight status, weight perception, weight satisfaction, and the four created lifestyle groups (healthier behaviors, healthier diet only, physically active only, unhealthier behaviors). Results: Males with obesity were more likely to be in the healthier diet only group than males with a normal weight (OR = 1.90, 95% CI: 1.02, 3.52). Similar patterns were found in males who perceived themselves as being overweight or having obesity (OR = 2.09, 95% CI: 1.09, 3.99) and males with obesity who perceived their weight status accurately (OR = 2.33, 95% CI: 1.12, 4.88). Female respondents who were satisfied with their weight were 59% less likely to be in the healthier diet only group than healthier behaviors group compared with females who were weight dissatisfied (OR = 0.41, 95% CI: 0.23, 0.75). This pattern was not observed in males. Conclusions: Clustering PA and dietary behaviors were associated with weight status and weight perception for males but not females. Weight satisfaction was associated with clustered PA and dietary behaviors for females. These findings are important for obesity prevention policies and programs to better address adolescents’ obesity and reduce health disparities in this population.
    Print ISSN: 1661-7827
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    Topics: Energy, Environment Protection, Nuclear Power Engineering , Medicine
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  • 27
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    Publication Date: 2018-09-06
    Description: IJGI, Vol. 7, Pages 366: Introduction to the Special Issue: “State-of-the-Art Virtual/Augmented Reality and 3D Modeling Techniques for Virtual Urban Geographic Experiments” ISPRS International Journal of Geo-Information doi: 10.3390/ijgi7090366 Authors: Jianming Liang Jianhua Gong Yu Liu n/a
    Electronic ISSN: 2220-9964
    Topics: Architecture, Civil Engineering, Surveying , Geosciences
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  • 28
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    MDPI Publishing
    Publication Date: 2018-09-06
    Description: IJERPH, Vol. 15, Pages 1927: The Association of the 24 Hour Distribution of Time Spent in Physical Activity, Work, and Sleep with Emotional Exhaustion International Journal of Environmental Research and Public Health doi: 10.3390/ijerph15091927 Authors: Janina Janurek Sascha Abdel Hadi Andreas Mojzisch Jan Alexander Häusser Previous research identified time spent in physical activity, sleeping, and working as predictors of emotional exhaustion. However, this research did not take into account the interdependence of these time-use components. Since daily time is limited to 24 h, time spent in one specific activity (e.g., sleep) cannot be used for any other activity (e.g., physical activity). We conducted a one-week daily sampling study to assess the compositional effects of physical activity, sleep, and work on emotional exhaustion. Since the sample consisted of 104 undergraduate students, work was operationalized as study time. Participants wore accelerometers for one week continuously to assess sleep and physical activity. Also, they filled in questionnaires on study time and emotional exhaustion every morning. Multilevel and compositional data analyses were conducted. The multilevel analysis revealed significant between- (p = 0.012) and within-level (p < 0.001) associations of study time with emotional exhaustion. The compositional approach showed that time spent in physical activity was negatively related to emotional exhaustion (p = 0.007), whereas time spent studying was positively related to emotional exhaustion (p = 0.003), relative to the remaining two time-use components. In conclusion, our results show that emotional exhaustion is not only associated with work-related factors, but also with off-job physical activity.
    Print ISSN: 1661-7827
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    Topics: Energy, Environment Protection, Nuclear Power Engineering , Medicine
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  • 29
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    Publication Date: 2018-09-06
    Description: Materials, Vol. 11, Pages 1627: Fabrication of Mo-Doped WO3 Nanorod Arrays on FTO Substrate with Enhanced Electrochromic Properties Materials doi: 10.3390/ma11091627 Authors: Bao Wang Wenkuan Man Haiyang Yu Yang Li Feng Zheng Well-oriented and crystalline WO3 nanorod arrays (WNRAs) decorated with Mo were synthesized on fluorine doped tin oxide (FTO) substrate by the hydrothermal method. The effects of Mo doping, hydrothermal reaction time, and hydrothermal temperature on the morphologies and electrochromic properties of as-prepared WNRAs were studied thoroughly. Scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and chronoamperometry techniques were used to characterize the structures and properties of obtained WNRAs. The results demonstrate that the average diameter of the as-prepared WNRAs ranged from 30 to 70 nm. During the decoration of Mo on the WNRAs, the growth density of as-prepared WNRAs decreased and the surfaces became rough. However, the decorated Mo on WNRAs synthesized at 180 °C for 5 h with a Mo/W mole ratio of 1:40 exhibited better electrochromic properties than single WNRAs. They exhibited high optical modulation (61.7%), fast bleaching/coloring response times (3 s/9 s), high coloration efficiency values (73.1 cm2/C), and good cycling stability.
    Electronic ISSN: 1996-1944
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
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  • 30
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    Publication Date: 2018-09-06
    Description: Materials, Vol. 11, Pages 1625: Dissolving Microneedle Patches for Transdermal Insulin Delivery in Diabetic Mice: Potential for Clinical Applications Materials doi: 10.3390/ma11091625 Authors: Chih-Hao Chen Victor Bong-Hang Shyu Chien-Tzung Chen In this study, dissolving polymeric microneedle (MN) patches composed of gelatin and sodium carboxymethyl cellulose (CMC) were used to localize insulin. Their in vitro skin insertion capabilities were determined using tissue-marking dye to stain the skin after patches removal. Scanning electron microscopy (SEM) was used to determine changes in the MNs over time, and optical coherence tomography (OCT) was used to monitor their real-time penetration depth. Confocal microscopy images revealed that rhodamine 6G gradually diffuses from the puncture sites to deeper dermal tissue. Using an in vivo imaging system (IVIS), skin areas that received FITC-insulin-loaded MNs were found to present strong fluorescent signals that greatly decreased 1 h after application. Results show that dissolving MNs rapidly release FITC-insulin, and it then gradually diffuses into the skin. This study verifies that using a gelatin/CMC MN patch for insulin delivery achieves satisfactory relative bioavailability compared to a traditional hypodermic injection and can be a promising delivery device for poorly permeable protein drugs such as those used to treat diabetes. Insertion tests on human cadaveric skin demonstrate that dissolving MNs could serve as efficient devices for transdermal drug delivery in clinical practice and that the volar aspect of forearm skin is the ideal location for their applications.
    Electronic ISSN: 1996-1944
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
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  • 31
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    MDPI Publishing
    Publication Date: 2018-09-06
    Description: Materials, Vol. 11, Pages 1624: ZnO/ZnAl2O4 Nanocomposite with 3D Sphere-Like Hierarchical Structure for Photocatalytic Reduction of Aqueous Cr(VI) Materials doi: 10.3390/ma11091624 Authors: Xiaoya Yuan Xin Cheng Qiuye Jing Jiawei Niu Dong Peng Zijuan Feng Xue Wu Three dimensional (3D) ZnO/ZnAl2O4 nanocomposites (ZnnAl-MMO) were synthesized by a simple urea-assisted hydrothermal process and subsequent high-temperature calcination. The as-prepared samples and their precursors were characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), UV-Vis diffuse reflectance spectroscopy (DRS), and Photoluminescence spectra (PL). It was observed that the morphology of ZnnAl-MMO nanocomposites could be tuned from cubic aggregates, hierarchically flower-like spheres to porous microspheres by simply changing the molar ratio of metal cations of the starting reaction mixtures. The photocatalytic performance of ZnO/ZnAl2O4 nanocomposites in the photoreduction of aqueous Cr(VI) indicated that the as-prepared 3D hierarchical sphere-like ZnnAl-MMO nanocomposite showed excellent photocatalytic activity of Cr(VI) reduction under UV light irradiation. The results indicated that the maximum removal percentage of aqueous Cr(VI) was 98% within four hours at 10 mg/L initial concentration of Cr(VI), owing to the effective charge separation and diversion of photogenerated carriers across the heterojunction interface of the composite. Our study put forward a facile method to fabricate hierarchical ZnO/ZnAl2O4 composites with potential applications for wastewater treatment.
    Electronic ISSN: 1996-1944
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
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  • 32
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    MDPI Publishing
    Publication Date: 2018-09-06
    Description: Materials, Vol. 11, Pages 1622: Hygrothermal and Acoustical Performance of Starch-Beet Pulp Composites for Building Thermal Insulation Materials doi: 10.3390/ma11091622 Authors: Hamzé Karaky Chadi Maalouf Christophe Bliard Tala Moussa Nadim El Wakil Mohammed Lachi Guillaume Polidori This article deals with the elaboration and the characterization of an innovative 100% plant-based green composite made solely of beet pulp (BP) and potato starch (S). Using this type of material in insulation applications seems a good solution to reduce the CO2 gas emissions in building. The influence of the starch amount on composite characteristics was studied. Four mixtures were considered with different S/BP mass ratios (0.1, 0.2, 0.3 and 0.4). The physical properties of these materials were studied in terms of porosity, apparent and absolute densities, thermal conductivity, and hygric properties. The influence of humidity content on acoustical properties was studied as a function of frequency. Test results show a real impact of both starch and humidity contents on the hygrothermal and acoustical properties of the studied material due to the porosity. The composite with the lowest amount of starch (S/BP = 0.1) seems to be the optimal composition in terms of the hygrothermal and acoustical behaviors.
    Electronic ISSN: 1996-1944
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
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  • 33
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    MDPI Publishing
    Publication Date: 2018-09-06
    Description: Materials, Vol. 11, Pages 1620: Push-Out Bond Strength and SEM Evaluation in Roots Filled with Two Different Techniques Using New and Conventional Sealers Materials doi: 10.3390/ma11091620 Authors: Pervin Dabaj Atakan Kalender Ayce Unverdi Eldeniz The aim of this study was to evaluate the influence of calcium-silicate-based sealer (Endosequence-BC-Sealer) in roots, filled with thermo-plasticized injectable technique aided by Calamus-Flow-Delivery-System, on bond strength to radicular dentin, in comparison with conventional epoxy-resin-based sealer (AH-Plus) along with cold-lateral-compaction technique. Root canals of mandibular-premolar teeth (n = 80) were instrumented using Protaper Universal rotary files and were randomly divided into four experimental groups (n = 20) as follows: (1) AH-Plus + cold-lateral-compaction technique; (2) Endosequence-BC-Sealer + cold-lateral-compaction technique; (3) AH-Plus + thermo-plasticized injectable technique; and (4) Endosequence-BC-Sealer + thermo-plasticized injectable technique. Horizontal disc shaped samples from each group (n = 60/group) were obtained and push-out bond strength testing was performed at a cross-head speed of 0.5 mm/min. Data were analyzed statistically using nonparametric Kruskal-Wallis analysis and Mann-Whitney test (p < 0.001). The statistical analysis revealed a significant difference amongst the groups (p < 0.001). The highest bond strength values were found in group 1 compared with all the other experimental groups (p < 0.001), whereas the lowest bond strength values were found in group 4 (p < 0.001). It was concluded that thermo-plasticized injectable technique with Calamus-Flow-Delivery-System lowered the bond strengths of the sealers, especially Endosequence-BC-Sealer. Therefore, this technique is not recommended to calcium-silicate-based sealers. Further studies are needed to confirm the findings of this study.
    Electronic ISSN: 1996-1944
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
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  • 34
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    Publication Date: 2018-09-06
    Description: Materials, Vol. 11, Pages 1616: A Novel Fluorescent Biosensor for Adenosine Triphosphate Detection Based on a Metal–Organic Framework Coating Polydopamine Layer Materials doi: 10.3390/ma11091616 Authors: Peipei Xu Guangfu Liao In this work, a novel and sensitive fluorescent biosensor based on polydopamine coated Zr-based metal–organic framework (PDA/UiO-66) is presented for adenosine triphosphate (ATP) detection. This PDA/UiO-66 nanoparticle which holds a great potential to be excellent fluorescence quencher can protect the 6-carboxyfluorescein (FAM)-labeled probe from cleaved by DNase I dispersed in solution and the flurescence of labeled FAM is quenched. When ATP molecules exist, aptamers on the PDA/UiO-66 nanoparticles can hybridize with ATP molecule to form complex structure that will be desorbed from the PDA/UiO-66 and digested by DNase I. After that, the released ATP molecule can react with another aptamer on the PDA/UiO-66 complexes, then restarts a new cycle. Herein, the excellent strong fluorescence quenching ability and uploading more amount of aptamer probes of PDA/UiO-66 composites make them efficient biosensors, leading to a high sensitivity with detection limit of 35 nM. Compared with ATP detection directly by UiO-66-based method, the LOD is about 5.7 times higher with PDA/UiO-66 nanoparticle. Moreover, the enhanced biocompatibility and bioactivity with PDA layer of the composites render a proposed strategy for clinical diagnosis field of detecting small biological molecules in vivo in the future.
    Electronic ISSN: 1996-1944
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
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  • 35
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    MDPI Publishing
    Publication Date: 2018-09-06
    Description: Materials, Vol. 11, Pages 1617: Correction: Control of the Size of Silver Nanoparticles and Release of Silver in Heat Treated SiO2-Ag Composite Powders. Materials 2018, 11, 80 Materials doi: 10.3390/ma11091617 Authors: Henrika Granbohm Juha Larismaa Saima Ali Leena-Sisko Johansson Simo-Pekka Hannula In the published article “Control of the Size of Silver Nanoparticles and Release of Silver in Heat Treated SiO2-Ag Composite Powders” [1] a reference was omitted in the caption of Figure 4b. [...]
    Electronic ISSN: 1996-1944
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
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  • 36
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    Publication Date: 2018-09-06
    Description: Minerals, Vol. 8, Pages 388: Ore-Forming Processes at the Xiajinbao Gold Deposit in Eastern Hebei Province: Constraints from EPMA and LA-ICPMS Analysis Minerals doi: 10.3390/min8090388 Authors: Cheng Wang Yongjun Shao Kuanxin Huang Haodi Zhou Jianguo Zhang Zhongfa Liu Qingquan Liu The Xiajinbao gold deposit is located at the northern margin of the North China Craton. Hydrothermal pyrites belonging to three stages were identified: Py1; Py2; and Py3. Geochemical study of these pyrites was conducted using electron probe microanalysis and laser ablation inductively coupled plasma mass spectrometry to investigate the distributions of minor and trace elements, constrain pyrite genesis, and to obtain an improved understanding of the ore-forming processes. Py1 and Py2 contain high concentrations of Au and are interpreted to have been deposited from fluids from a dominantly magmatic source. Py3 grains have the lowest Co/Ni ratios. All generations of pyrite were deposited by mixing of meteoric waters with magmatic-hydrothermal fluids. Boiling of early ore-forming fluids led to the precipitation of Py1 and gold. Decreasing fO2 in the ore-forming system resulted in the formation of Py2 and gold. Fluid mixing was the dominant controlling factor for the precipitation of Py3 together with small amounts of gold.
    Electronic ISSN: 2075-163X
    Topics: Geosciences
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  • 37
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    Publication Date: 2018-09-07
    Description: Minerals, Vol. 8, Pages 391: Interpretation of Hydrophobization Behavior of Dodecylamine on Muscovite and Talc Surface through Dynamic Wettability and AFM Analysis Minerals doi: 10.3390/min8090391 Authors: Hao Jiang Ya Gao Sultan Ahmed Khoso Wanying Ji Yuehua Hu In this study, a new approach, “dynamic wettability”, and atomic force microscopy (AFM) imaging analysis techniques were successfully used to characterize the hydrophobization mechanism of the collector dodecylamine (DDA) on muscovite and talc surfaces. The attachment of bubbles to the minerals was studied through the dynamic contact angle to gain a detailed understanding of the hydrophobization mechanism of DDA on a muscovite and talc surface. AFM imaging and interaction forces were performed to explain the DDA adsorption mechanism on both minerals. Finally, flotation tests were performed to verify the effectiveness of these techniques. After treatments with DDA, the contact angles became much larger compared to initial angles, particularly for muscovite, and the attachment of bubbles on the talc surface was much easier than muscovite due to its natural hydrophobicity. From AFM imaging, both the muscovite and talc showed a similar tendency; the higher the DDA concentration, the more the adsorbed amount. However, the adsorbed amount of DDA on talc surface was obviously more than that on muscovite. As far as interaction forces are concerned, the maximum attractions occurred at certain different concentrations respectively for muscovite and talc and agreed well with the AFM-imaging results. Moreover, results obtained from flotation tests were promising and quite in agreement with the phenomenon of these techniques.
    Electronic ISSN: 2075-163X
    Topics: Geosciences
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  • 38
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    MDPI Publishing
    Publication Date: 2018-09-07
    Description: Minerals, Vol. 8, Pages 390: Evaluation of Magnetic Separation Efficiency on a Cassiterite-Bearing Skarn Ore by Means of Integrative SEM-Based Image and XRF–XRD Data Analysis Minerals doi: 10.3390/min8090390 Authors: Markus Buchmann Edgar Schach Raimon Tolosana-Delgado Thomas Leißner Jennifer Astoveza Marius Kern Robert Möckel Doreen Ebert Martin Rudolph Karl Gerald van den Boogaart Urs A. Peuker Image analysis data obtained from scanning electron microscopy provided data for a detailed evaluation of the separation efficiency for various processes involving the beneficiation of particulate materials. A dry magnetic separation by a drum type magnetic separator served as a case study to visualize effects of processing of a skarn ore with a high content of cassiterite as ore mineral (~4 wt%). For this material, iron oxides and silicates are the main gangue mineral groups. Based on the obtained data, partition curves were generated with the help of local regression. From the partition curves, the separation efficiency was evaluated and the relevant particle properties deduced. A detailed analysis of the bias of the quantitative mineralogical data is presented. This bias was monitored and further analyzed in detail. Thorough analysis of feed and products of magnetic separation enabled identification of the most important factors that control losses of cassiterite to the magnetic product, namely the association with iron oxides and particle sizes below ~40 µm. The introduced methodology is a general approach applicable for the optimization of different separation processes and is not limited to the presented case study.
    Electronic ISSN: 2075-163X
    Topics: Geosciences
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  • 39
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    Publication Date: 2018-09-07
    Description: Remote Sensing, Vol. 10, Pages 1416: A Super-Resolution and Fusion Approach to Enhancing Hyperspectral Images Remote Sensing doi: 10.3390/rs10091416 Authors: Chiman Kwan Joon Hee Choi Stanley H. Chan Jin Zhou Bence Budavari High resolution (HR) hyperspectral (HS) images have found widespread applications in terrestrial remote sensing applications, including vegetation monitoring, military surveillance and reconnaissance, fire damage assessment, and many others. They also find applications in planetary missions such as Mars surface characterization. However, resolutions of most HS imagers are limited to tens of meters. Existing resolution enhancement techniques either require additional multispectral (MS) band images or use a panchromatic (pan) band image. The former poses hardware challenges, whereas the latter may have limited performance. In this paper, we present a new resolution enhancement algorithm for HS images that only requires an HR color image and a low resolution (LR) HS image cube. Our approach integrates two newly developed techniques: (1) A hybrid color mapping (HCM) algorithm, and (2) A Plug-and-Play algorithm for single image super-resolution. Comprehensive experiments (objective (five performance metrics), subjective (synthesized fused images in multiple spectral ranges), and pixel clustering) using real HS images and comparative studies with 20 representative algorithms in the literature were conducted to validate and evaluate the proposed method. Results demonstrated that the new algorithm is very promising.
    Electronic ISSN: 2072-4292
    Topics: Architecture, Civil Engineering, Surveying , Geography
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  • 40
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    Publication Date: 2018-09-07
    Description: Remote Sensing, Vol. 10, Pages 1418: Mapping High Mountain Lakes Using Space-Borne Near-Nadir SAR Observations Remote Sensing doi: 10.3390/rs10091418 Authors: Shengyang Li Hong Tan Zhiwen Liu Zhuang Zhou Yunfei Liu Wanfeng Zhang Kang Liu Bangyong Qin Near-nadir interferometric imaging SAR (Synthetic Aperture Radar) techniques are promising in measuring global water extent and surface height at fine spatial and temporal resolutions. The concept of near-nadir interferometric measurements was implemented in the experimental Interferometric Imaging Radar Altimeters (InIRA) mounted on Chinese Tian Gong 2 (TG-2) space laboratory. This study is focused on mapping the extent of high mountain lakes in the remote Qinghai–Tibet Plateau (QTP) areas using the InIRA observations. Theoretical simulations were first conducted to understand the scattering mechanisms under near-nadir observation geometry. It was found that water and surrounding land pixels are generally distinguishable depending on the degree of their difference in dielectric properties and surface roughness. The observed radar backscatter is also greatly influenced by incidence angles. A dynamic threshold method was then developed to detect water pixels based on the theoretical analysis and ancillary data. As assessed by the LandSat results, the overall classification accuracy is higher than 90%, though the classifications are affected by low backscatter possibly from very smooth water surface. The algorithms developed from this study can be extended to all InIRA land measurements and provide support for the similar space missions in the future.
    Electronic ISSN: 2072-4292
    Topics: Architecture, Civil Engineering, Surveying , Geography
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  • 41
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    MDPI Publishing
    Publication Date: 2018-09-07
    Description: Remote Sensing, Vol. 10, Pages 1419: Evaluation of Different Machine Learning Algorithms for Scalable Classification of Tree Types and Tree Species Based on Sentinel-2 Data Remote Sensing doi: 10.3390/rs10091419 Authors: Mathias Wessel Melanie Brandmeier Dirk Tiede We use freely available Sentinel-2 data and forest inventory data to evaluate the potential of different machine-learning approaches to classify tree species in two forest regions in Bavaria, Germany. Atmospheric correction was applied to the level 1C data, resulting in true surface reflectance or bottom of atmosphere (BOA) output. We developed a semiautomatic workflow for the classification of deciduous (mainly spruce trees), beech and oak trees by evaluating different classification algorithms (object- and pixel-based) in an architecture optimized for distributed processing. A hierarchical approach was used to evaluate different band combinations and algorithms (Support Vector Machines (SVM) and Random Forest (RF)) for the separation of broad-leaved vs. coniferous trees. The Ebersberger forest was the main project region and the Freisinger forest was used in a transferability study. Accuracy assessment and training of the algorithms was based on inventory data, validation was conducted using an independent dataset. A confusion matrix, with User´s and Producer´s Accuracies, as well as Overall Accuracies, was created for all analyses. In total, we tested 16 different classification setups for coniferous vs. broad-leaved trees, achieving the best performance of 97% for an object-based multitemporal SVM approach using only band 8 from three scenes (May, August and September). For the separation of beech and oak trees we evaluated 54 different setups, the best result achieved an accuracy of 91% for an object-based, SVM, multitemporal approach using bands 8, 2 and 3 of the May scene for segmentation and all principal components of the August scene for classification. The transferability of the model was tested for the Freisinger forest and showed similar results. This project points out that Sentinel-2 had only marginally worse results than comparable commercial high-resolution satellite sensors and is well-suited for forest analysis on a tree-stand level.
    Electronic ISSN: 2072-4292
    Topics: Architecture, Civil Engineering, Surveying , Geography
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  • 42
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    MDPI Publishing
    Publication Date: 2018-09-07
    Description: Remote Sensing, Vol. 10, Pages 1417: Underground Object Classification for Urban Roads Using Instantaneous Phase Analysis of Ground-Penetrating Radar (GPR) Data Remote Sensing doi: 10.3390/rs10091417 Authors: Byeongjin Park Jeongguk Kim Jaesun Lee Man-Sung Kang Yun-Kyu An Ground-penetrating radar (GPR) has been widely used to detect subsurface objects, such as hidden cavities, buried pipes, and manholes, owing to its noncontact sensing, rapid scanning, and deeply penetrating remote-sensing capabilities. Currently, GPR data interpretation depends heavily on the experience of well-trained experts because different types of underground objects often generate similar GPR reflection features. Moreover, reflection visualizations that were obtained from field GPR data for urban roads are often weak and noisy. This study proposes a novel instantaneous phase analysis technique to address these issues. The proposed technique aims to enhance the visibility of underground objects and provide objective criteria for GPR data interpretation so that the objects can be automatically classified without expert intervention. The feasibility of the proposed technique is validated both numerically and experimentally. The field test utilizes rarely available GPR data for urban roads in Seoul, South Korea and demonstrates that the technique allows for successful visualization and classification of three different types of underground objects.
    Electronic ISSN: 2072-4292
    Topics: Architecture, Civil Engineering, Surveying , Geography
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  • 43
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    MDPI Publishing
    Publication Date: 2018-09-07
    Description: Remote Sensing, Vol. 10, Pages 1420: Component Analysis of Errors in Four GPM-Based Precipitation Estimations over Mainland China Remote Sensing doi: 10.3390/rs10091420 Authors: Jianbin Su Haishen Lü Yonghua Zhu Xiaoyi Wang Guanghua Wei As the Global Precipitation Measurement (GPM) Core Observatory satellite continues its mission, the latest GPM-era satellite-based precipitation estimations, including Global Satellite Mapping of Precipitation (GSMaP) and Integrated Multi-satellitE Retrievals for the GPM (IMERG), have been released. However, few studies have systematically evaluated these products over mainland China, although this is very important for both the end users and data developers. To these ends, the final-run uncalibrated IMERG V05 (V05UC), gauge-calibrated IMERG V05 (V05C) and IMERG V04 (V04C), and latest gauge-calibrated GSMaP V7 (GSMaP) are systematically evaluated and mutually compared against a merged product obtained from the China Meteorological Data Service Center via continuous statistical indices and an error decomposition analysis technology suite over mainland China from April 2014 to December 2016 at a 3 hourly scale and 0.1° × 0.1° resolution. The results show that, irrespective of the slight overestimation in the southeast and underestimation in the northern Tibetan Plateau, all four GSPEs could generally capture the spatial patterns of precipitation over mainland China. Meanwhile, the overall quality of the GSMaP is slightly superior to the IMERG products in east and south China; however, it also suffers from an overestimation of light rain and an underestimation of heavy rain. Such overestimation and underestimation are primarily from a large false precipitation in light rain and a negative hit bias in heavy rain, respectively. The latest IMERG V05 products have not shown significant improvement over the earlier version (V04C) in east and south China, but the calibrated V05C can best reproduce the probability density function in terms of precipitation intensity. Furthermore, V04C shows remarkable underestimation over the Tibetan Plateau, while this shortcoming has been resolved significantly in V05C. Alternately, the effects of the gauge calibration algorithm (GCA) used in IMERG are examined by comparison of V05UC and V05C. The results indicate that GCA cannot reduce the missed precipitation, and even enlarges the false precipitation over some regions. This reveals that GCA cannot effectively alleviate the bias resulting from the rain areas’ delineation and raining or not-raining detection. In addition, all of the products’ performance can be improved, particularly in the dry climate and high-latitude regions. This is a systematic estimation for GSPEs, providing deep insight into the characteristics and sources of error, and it could be valuable as a reference for both algorithm developers and data users, as well as for associated global products and various applications.
    Electronic ISSN: 2072-4292
    Topics: Architecture, Civil Engineering, Surveying , Geography
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  • 44
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    MDPI Publishing
    In: Sensors
    Publication Date: 2018-09-06
    Description: Sensors, Vol. 18, Pages 2957: Motion Artifact Correction of Multi-Measured Functional Near-Infrared Spectroscopy Signals Based on Signal Reconstruction Using an Artificial Neural Network Sensors doi: 10.3390/s18092957 Authors: Gihyoun Lee Sang Hyeon Jin Jinung An In this paper, a new motion artifact correction method is proposed based on multi-channel functional near-infrared spectroscopy (fNIRS) signals. Recently, wavelet transform and hemodynamic response function-based algorithms were proposed as methods of denoising and detrending fNIRS signals. However, these techniques cannot achieve impressive performance in the experimental environment with lots of movement such as gait and rehabilitation tasks because hemodynamic responses have features similar to those of motion artifacts. Moreover, it is difficult to correct motion artifacts in multi-measured fNIRS systems, which have multiple channels and different noise features in each channel. Thus, a new motion artifact correction method for multi-measured fNIRS is proposed in this study, which includes a decision algorithm to determine the most contaminated fNIRS channel based on entropy and a reconstruction algorithm to correct motion artifacts by using a wavelet-decomposed back-propagation neural network. The experimental data was achieved from six subjects and the results were analyzed in comparing conventional algorithms such as HRF smoothing, wavelet denoising, and wavelet MDL. The performance of the proposed method was proven experimentally using the graphical results of the corrected fNIRS signal, CNR that is a performance evaluation index, and the brain activation map.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 45
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    MDPI Publishing
    In: Sensors
    Publication Date: 2018-09-06
    Description: Sensors, Vol. 18, Pages 2952: An Autonomous Vehicle Navigation System Based on Inertial and Visual Sensors Sensors doi: 10.3390/s18092952 Authors: Xingxing Guang Yanbin Gao Henry Leung Pan Liu Guangchun Li The strapdown inertial navigation system (SINS) is widely used in autonomous vehicles. However, the random drift error of gyroscope leads to serious accumulated navigation errors during long continuous operation of SINS alone. In this paper, we propose to combine the Inertial Measurement Unit (IMU) data with the line feature parameters from a camera to improve the navigation accuracy. The proposed method can also maintain the autonomy of the navigation system. Experimental results show that the proposed inertial-visual navigation system can mitigate the SINS drift and improve the accuracy, stability, and reliability of the navigation system.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 46
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    MDPI Publishing
    In: Sensors
    Publication Date: 2018-09-06
    Description: Sensors, Vol. 18, Pages 2954: Performance Characterization of GNSS/IMU/DVL Integration under Real Maritime Jamming Conditions Sensors doi: 10.3390/s18092954 Authors: Ralf Ziebold Daniel Medina Michailas Romanovas Christoph Lass Stefan Gewies Currently Global Navigation Satellite Systems (GNSSs) are the primary source for the determination of absolute position, navigation, and time (PNT) for merchant vessel navigation. Nevertheless, the performance of GNSSs can strongly degrade due to space weather events, jamming, and spoofing. Especially the increasing availability and adoption of low cost jammers lead to the question of how a continuous provision of PNT data can be realized in the vicinity of these devices. In general, three possible solutions for that challenge can be seen: (i) a jamming-resistant GNSS receiver; (ii) the usage of a terrestrial backup system; or (iii) the integration of GNSS with other onboard navigation sensors such as a speed log, a gyrocompass, and inertial sensors (inertial measurement unit—IMU). The present paper focuses on the third option by augmenting a classical IMU/GNSS sensor fusion scheme with a Doppler velocity log. Although the benefits of integrated IMU/GNSS navigation system have been already demonstrated for marine applications, a performance evaluation of such a multi-sensor system under real jamming conditions on a vessel seems to be still missing. The paper evaluates both loosely and tightly coupled fusion strategies implemented using an unscented Kalman filter (UKF). The performance of the proposed scheme is evaluated using the civilian maritime jamming testbed in the Baltic Sea.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 47
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    MDPI Publishing
    Publication Date: 2018-09-06
    Description: Symmetry, Vol. 10, Pages 382: Some New Symmetric Equilateral Embeddings of Platonic and Archimedean Polyhedra Symmetry doi: 10.3390/sym10090382 Authors: Kris Coolsaet Stan Schein The icosahedron and the dodecahedron have the same graph structures as their algebraic conjugates, the great dodecahedron and the great stellated dodecahedron. All four polyhedra are equilateral and have planar faces—thus “EP”—and display icosahedral symmetry. However, the latter two (star polyhedra) are non-convex and “pathological” because of intersecting faces. Approaching the problem analytically, we sought alternate EP-embeddings for Platonic and Archimedean solids. We prove that the number of equations—E edge length equations (enforcing equilaterality) and 2 E − 3 F face (torsion) equations (enforcing planarity)—and of variables ( 3 V − 6 ) are equal. Therefore, solutions of the equations up to equivalence generally leave no degrees of freedom. As a result, in general there is a finite (but very large) number of solutions. Unfortunately, even with state-of-the-art computer algebra, the resulting systems of equations are generally too complicated to completely solve within reasonable time. We therefore added an additional constraint, symmetry, specifically requiring solutions to display (at least) tetrahedral symmetry. We found 77 non-classical embeddings, seven without intersecting faces—two, four and one, respectively, for the (graphs of the) dodecahedron, the icosidodecahedron and the rhombicosidodecahedron.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 48
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    MDPI Publishing
    In: Water
    Publication Date: 2018-09-06
    Description: Water, Vol. 10, Pages 1197: Hydropower Future: Between Climate Change, Renewable Deployment, Carbon and Fuel Prices Water doi: 10.3390/w10091197 Authors: Alessandro Ranzani Mattia Bonato Epari Ritesh Patro Ludovic Gaudard Carlo De Michele Hydropower represents an interesting technology: affordable, renewable, and flexible. However, it must cope with climate changes and new energy policies that jeopardize its future. A smooth transition to sustainability requires decision makers to assess the future perspectives of hydropower: about its future revenue and related uncertainty. This investigation requires a multidisciplinary approach as both streamflow and energy mix will evolve. We simulated future streamflow based on eight climate scenarios using a semi-distributed hydrological model for our case study, the Tremorgio hydropower plant located in southern Switzerland. Next, using a hydropower management model we generated income according to these streamflows and twenty-eight electricity price scenarios. Our results indicate that climate change will modify the seasonality of inflows and volumes exploitable for hydropower generation. However, adaptive strategies in the management of reservoirs could minimize revenue losses/maximize revenue gains. In addition, most market scenarios project an increase in revenues, except in the case of high wind and solar energy penetration. Markets do not provide the right incentive, since the deployment of intermittent energy would benefit from more flexible hydropower.
    Electronic ISSN: 2073-4441
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 49
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    MDPI Publishing
    In: Water
    Publication Date: 2018-09-06
    Description: Water, Vol. 10, Pages 1196: Numerical Simulation of Gate Control for Unsteady Irrigation Flow to Improve Water Use Efficiency in Farming Water doi: 10.3390/w10091196 Authors: Tianyu Fang Yu Gu Xiangli He Xiaodong Liu Yu Han Jian Chen In the case of irrigation, to implement the water distribution plan, the flow needs to be changed through the gate which leads to the occurrence of unavoidable unsteady flow. In order to improve the level of irrigation management, it is necessary to understand the changes taking place in the canal water flow during the process of water distribution. The de Saint-Venant equations were solved based on the method of characteristics and a model was built to simulate the unsteady flow in the channel of the Yintang irrigation district. Then, the obtained results were validated by the employed model. On the basis of simulation results, a model for the variations in the gate opening was established based on the theory of under-gate discharge. In this study, the simulation results, as established from the model, are very consistent with the simulation results of existing commercial software and a simple design for the operation was conducted from the adjustment of gate openings and multi-stage gate operation modes. Overall, the established gate control model built in this study is reliable, which provides a basis for the decision-making process for the relevant staff.
    Electronic ISSN: 2073-4441
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 50
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    MDPI Publishing
    In: Water
    Publication Date: 2018-09-06
    Description: Water, Vol. 10, Pages 1194: Quantification of Daily Water Requirements of Container-Grown Calathea and Stromanthe Produced in a Shaded Greenhouse Water doi: 10.3390/w10091194 Authors: Richard C. Beeson Jianjun Chen Irrigating plants based on their water requirements enhances water use efficiency and conservation; however, current irrigation practices for container-grown greenhouse plants largely relies on growers’ experiences, resulting in leaching and/or runoff of a large amount of water. To address water requirements of greenhouse-grown plants, this study adapted a canopy closure model and investigated actual evapotranspiration (ETA) of Calathea G. Mey. ‘Silhouette’ and Stromanthe sanguinea Sond. from transplanting to marketable sizes in a shaded greenhouse. The daily ETA per Calathea plant ranged from 3.55 mL to 59.39 mL with a mean cumulative ETA of 4.84 L during a 224 day growth period. The daily ETA of S. sanguinea varied from 7.87 mL to 97.27 mL per plant with a mean cumulative ETA of 6.81 L over a 231 day production period. The best fit models for predicting daily ETA of Calathea and Stromanthe were developed, which had correlation coefficients (r2) of 0.82 and 0.73, respectively. The success in modelling ETA of the two species suggested that the canopy closure model was suitable for quantifying water use of container-grown greenhouse plants. Applying the research-based ETA information in production could reduce water use and improve irrigation efficiency during Calathea and Stromanthe production.
    Electronic ISSN: 2073-4441
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 51
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    MDPI Publishing
    In: Water
    Publication Date: 2018-09-06
    Description: Water, Vol. 10, Pages 1193: Making the Case for a Female-Friendly Toilet Water doi: 10.3390/w10091193 Authors: Margaret L. Schmitt David Clatworthy Tom Ogello Marni Sommer Inadequate access to a private, comfortable, and well-located toilet remains a critical challenge for many girls and women around the world. This issue is especially acute for girls and women living in densely populated urban slums, displacement camps, and informal settlements, often resulting in anxiety, embarrassment, discomfort, and gender-based violence. The unique sanitation needs of girls and women are rarely accounted for during the design and construction of toilet facilities, including needs related to their physiology, reproductive health processes, prevalent social norms, and their heightened vulnerability to violence. It is critical that a new norm be developed regarding the design of female-friendly toilets which better enables girls and women to feel confident, safe, and dignified while managing their daily sanitation needs. This includes adopting specific design measures which account for their menstrual hygiene, personal safety, and dignity-related needs. Ultimately, an enhanced dialogue must take place among designers, policy makers, water, sanitation, and hygiene (WASH) practitioners, and other relevant actors, in addition to the target female users themselves, about how to adapt toilets in a range of development and emergency contexts and operations to better address these critical needs of girls and women.
    Electronic ISSN: 2073-4441
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 52
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    MDPI Publishing
    Publication Date: 2018-09-07
    Description: Algorithms, Vol. 11, Pages 133: A Modified Sufficient Descent Polak–Ribiére–Polyak Type Conjugate Gradient Method for Unconstrained Optimization Problems Algorithms doi: 10.3390/a11090133 Authors: Xiuyun Zheng Jiarong Shi In this paper, a modification to the Polak–Ribiére–Polyak (PRP) nonlinear conjugate gradient method is presented. The proposed method always generates a sufficient descent direction independent of the accuracy of the line search and the convexity of the objective function. Under appropriate conditions, the modified method is proved to possess global convergence under the Wolfe or Armijo-type line search. Moreover, the proposed methodology is adopted in the Hestenes–Stiefel (HS) and Liu–Storey (LS) methods. Extensive preliminary numerical experiments are used to illustrate the efficiency of the proposed method.
    Electronic ISSN: 1999-4893
    Topics: Computer Science
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  • 53
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    MDPI Publishing
    In: Water
    Publication Date: 2018-09-06
    Description: Water, Vol. 10, Pages 1180: Optimal Irrigation Mode and Spatio-Temporal Variability Characteristics of Soil Moisture Content in Different Growth Stages of Winter Wheat Water doi: 10.3390/w10091180 Authors: Yujian Yang Yanbo Huang Yong Zhang Xueqin Tong To advance site-specific management of soil volumetric moisture content (VMC), this study analyzed the spatio-temporal evolution characteristics of soil VMC using the method of sequential Gaussian simulation (SGS) during the different growth stages of winter wheat. This was compared with data measured by time domain reflectometry (TDR) which is a well-established electromagnetic technique to measure soil VMC. The spatial autocorrelation coefficient of VMC indicated the strongest clustering of VMC in the tillering stage, and the least clustering of VMC in the harvest stage. A threshold of VMC in topsoil in the jointing stage of winter wheat was put forward. This threshold is 26, signifying that at a lower value, irrigation should be performed and irrigation efficiencies can be improved. Stable and sub-stable areas in the spatial variability maps of VMC were identified in the winter wheat jointing stage. Furthermore, the optimal irrigation stage was the early jointing stage, and irrigation was performed once as a guide. A loose-couple spatial model was constructed using the VMC in topsoil and the volume of water for irrigation. The VMC in the jointing stage of winter wheat was linked with efficient and water-saving irrigation.
    Electronic ISSN: 2073-4441
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 54
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    MDPI Publishing
    In: Water
    Publication Date: 2018-09-06
    Description: Water, Vol. 10, Pages 1192: Microspheres as Surrogate Helminth Eggs: A Comparative Labscale Sedimentation Study for Tap- and Wastewater Water doi: 10.3390/w10091192 Authors: Barbara K. Arthur Edith Nettmann Andrea Rademacher Manfred Lübken Bernd Marschner Marc Wichern Re-use of water containing helminth eggs during irrigation for agricultural purposes poses health risks, and likewise during research, due to the potential of spreading on contact. Therefore, polystyrene latex microspheres could be used as surrogates for chemical or biological species during colloidal transport. The aim here is to compare the settling velocities of microspheres having varied surface coatings—that is, proteins A, G and A/G; with that of real helminth eggs obtained from literature. The settling velocities of the microspheres were experimentally determined in tap- and wastewater, as well as theoretically in tap water; which was found to be within the range of mean values for those experimentally determined. There were no differences amongst the microspheres types used for settling in wastewater (i.e., A = 0.072 ± 0.02; G = 0.060 ± 0.03; A/G = 0.053 ± 0.01 mm/s). The same applied for settling in tap water (i.e., A = 0.068 ± 0.02; G = 0.047 ± 0.004; A/G = 0.095 ± 0.02 mm/s), except for microsphere G being different from microsphere A/G. All three types of microspheres settled at velocities lower than that of the wastewater particles (=0.118 ± 0.03). T-test analyses of settling velocities of microspheres in both tap- and wastewater, versus that from literature (i.e., Ascaris, Trichuris and Oesophagostomum), showed that microsphere A and A/G may surrogate for Ascaris in tap water, the same as A/G for Oesophagostomum. In wastewater however, both microspheres A and G are a good fit for Trichuris.
    Electronic ISSN: 2073-4441
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 55
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    MDPI Publishing
    In: Sensors
    Publication Date: 2018-09-07
    Description: Sensors, Vol. 18, Pages 2979: Modeling the Human Visuo-Motor System to Support Remote-Control Operation Sensors doi: 10.3390/s18092979 Authors: Jonathan Andersh Bérénice Mettler The working hypothesis in this project is that gaze interactions play a central role in structuring the joint control and guidance strategy of the human operator performing spatial tasks. Perceptual guidance and control is the idea that the visual and motor systems form a unified perceptuo-motor system where necessary information is naturally extracted by the visual system. As a consequence, the response of this system is constrained by the visual and motor mechanisms and these effects should manifest in the behavioral data. Modeling the perceptual processes of the human operator provides the foundation necessary for a systems-based approach to the design of control and display systems used by remotely operated vehicles. This paper investigates this hypothesis using flight tasks conducted with remotely controlled miniature rotorcraft, taking place in indoor settings that provide rich environments to investigate the key processes supporting spatial interactions. This work also applies to spatial control tasks in a range of application domains that include tele-operation, gaming, and virtual reality. The human-in-the-loop system combines the dynamics of the vehicle, environment, and human perception–action with the response of the overall system emerging from the interplay of perception and action. The main questions to be answered in this work are as follows: (i) what is the general control and guidance strategy of the human operator, and (ii) how is information about the vehicle and environment extracted visually by the operator. The general approach uses gaze as the primary sensory mechanism by decoding the gaze patterns of the pilot to provide information for estimation, control, and guidance. This work differs from existing research by taking what have largely been conceptual ideas on action–perception and structuring them to be implemented for a real-world problem. The paper proposes a system model that captures the human pilot’s perception–action loop; the loop that delineates the main components of the pilot’s perceptuo-motor system, including estimation of the vehicle state and task elements based on operator gaze patterns, trajectory planning, and tracking control. The identified human visuo-motor model is then exploited to demonstrate how the perceptual and control functions system can be augmented to reduce the operator workload.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 56
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    Publication Date: 2018-09-08
    Description: Energies, Vol. 11, Pages 2369: Total Cost of Ownership Based Economic Analysis of Diesel, CNG and Electric Bus Concepts for the Public Transport in Istanbul City Energies doi: 10.3390/en11092369 Authors: Orhan Topal İsmail Nakir As across the world, in Turkey, several studies have been carried out by local government to use sustainable and 100% zero-emission public transport following increased public awareness. Increasing greenhouse gas emissions (GHG) due to transportation systems in the world make it necessary to establish “zero-emission sustainable transportation systems” in Turkey. In this study, an economic analysis based on actual field data is presented for Istanbul Electricity, Tramway and Tunnel General Management (IETT) to seek the suitability of an electric bus concept for Istanbul conditions. For this purpose, a dynamic model based on the Total Cost of Ownership (TCO) from well to wheel has been proposed for the three groups of transportation, namely diesel, CNG (compressed natural gas) and electric buses. The data source used in the proposed approach is created by performing actual field performance tests for diesel, CNG and electric buses under real Istanbul road, time, and trip conditions. Afterwards, the Net Present Value (NPV), Internal Rate of Return (IRR), and Payback Period (PB) methods considering TCO values and updated unit prices are carried out for the investment versus profitability analyses to compare the different public bus concepts. The results show that the electric bus concept with a charging station depot achieving sustainable and zero-emission goals will be the driving force to advance the electric bus concept for Istanbul Public Transport.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 57
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    Publication Date: 2018-09-08
    Description: Energies, Vol. 11, Pages 2367: A Mixed-Strategy-Based Whale Optimization Algorithm for Parameter Identification of Hydraulic Turbine Governing Systems with a Delayed Water Hammer Effect Energies doi: 10.3390/en11092367 Authors: Tan Ding Li Chang Chaoshun Li Chen Feng Nan Zhang For solving the parameter optimization problem of a hydraulic turbine governing system (HTGS) with a delayed water hammer (DWH) effect, a Mixed-Strategy-based Whale Optimization Algorithm (MSWOA) is proposed in this paper, in which three improved strategies are designed and integrated to promote the optimization ability. Firstly, the movement strategies of WOA have been improved to balance the exploration and exploitation. In the improved movement strategies, a dynamic ratio based on improved JAYA algorithm is applied on the strategy of searching for prey and a chaotic dynamic weight is designed for improving the strategies of bubble-net attacking and encircling prey. Secondly, a guidance of the elite’s memory inspired by Particle swarm optimization (PSO) is proposed to lead the movement of the population to accelerate the convergence speed. Thirdly, the mutation strategy based on the sinusoidal chaotic map is employed to avoid prematurity and local optimum points. The proposed MSWOA are compared with six popular meta-heuristic optimization algorithms on 23 benchmark functions in numerical experiments and the results show that the MSWOA has achieved significantly better performance than others. Finally, the MSWOA is applied on parameter identification problem of HTGS with a DWH effect, and the comparative results confirm the effectiveness and identification accuracy of the proposed method.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 58
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    Publication Date: 2018-09-08
    Description: Energies, Vol. 11, Pages 2364: Selection of Calibration Windows for Day-Ahead Electricity Price Forecasting Energies doi: 10.3390/en11092364 Authors: Grzegorz Marcjasz Tomasz Serafin Rafał Weron We conduct an extensive empirical study on the selection of calibration windows for day-ahead electricity price forecasting, which involves six year-long datasets from three major power markets and four autoregressive expert models fitted either to raw or transformed prices. Since the variability of prediction errors across windows of different lengths and across datasets can be substantial, selecting ex-ante one window is risky. Instead, we argue that averaging forecasts across different calibration windows is a robust alternative and introduce a new, well-performing weighting scheme for averaging these forecasts.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 59
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    Publication Date: 2018-09-08
    Description: Energies, Vol. 11, Pages 2363: Applied Research on Distributed Generation Optimal Allocation Based on Improved Estimation of Distribution Algorithm Energies doi: 10.3390/en11092363 Authors: Lei Yang Xiaohui Yang Yue Wu Xiaoping Liu Most of the current algorithms used to solve the optimal configuration problem in the distributed generation (DG) of electricity depend heavily on control parameters, which may lead to local optimal solutions. To achieve a rapid and effective algorithm of optimized configuration for distributed generation, a hybrid approach combined with Bayesian statistical-inference and distribution estimation is proposed. Specifically, a probability distribution estimation model based on the theory of Bayesian inference is established, then a posteriori probability model with the prior distribution and the conditional distribution is generated, and new individual generators are formed into a dominant group. The information of each individual of this dominant group is used to update the probability model and the updated posteriori probability is used for sampling until the optimal solution is obtained. Finally, the 12 bus, 34 bus and 69 bus radial distribution system is used as an example and comparison is performed to show the effectiveness of the proposed algorithm.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 60
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    Publication Date: 2018-09-08
    Description: Energies, Vol. 11, Pages 2361: Modelling, Parameter Identification, and Experimental Validation of a Lead Acid Battery Bank Using Evolutionary Algorithms Energies doi: 10.3390/en11092361 Authors: H. Eduardo Ariza Chacón Edison Banguero Antonio Correcher Ángel Pérez-Navarro Francisco Morant Accurate and efficient battery modeling is essential to maximize the performance of isolated energy systems and to extend battery lifetime. This paper proposes a battery model that represents the charging and discharging process of a lead-acid battery bank. This model is validated over real measures taken from a battery bank installed in a research center placed at “El Chocó”, Colombia. In order to fit the model, three optimization algorithms (particle swarm optimization, cuckoo search, and particle swarm optimization + perturbation) are implemented and compared, the last one being a new proposal. This research shows that the identified model is able to estimate real battery features, such as state of charge (SOC) and charging/discharging voltage. The comparison between simulations and real measures shows that the model is able to absorb reading problems, signal delays, and scaling errors. The approach we present can be implemented in other types of batteries, especially those used in stand-alone systems.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 61
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    In: Entropy
    Publication Date: 2018-09-08
    Description: Entropy, Vol. 20, Pages 683: Einstein-Podolsky-Rosen Steering Inequalities and Applications Entropy doi: 10.3390/e20090683 Authors: Ying Yang Huaixin Cao Einstein-Podolsky-Rosen (EPR) steering is very important quantum correlation of a composite quantum system. It is an intermediate type of nonlocal correlation between entanglement and Bell nonlocality. In this paper, based on introducing definitions and characterizations of EPR steering, some EPR steering inequalities are derived. With these inequalities, the steerability of the maximally entangled state is checked and some conditions for the steerability of the X -states are obtained.
    Electronic ISSN: 1099-4300
    Topics: Chemistry and Pharmacology , Physics
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  • 62
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    In: Entropy
    Publication Date: 2018-09-08
    Description: Entropy, Vol. 20, Pages 681: Analysis of Basic Features in Dynamic Network Models Entropy doi: 10.3390/e20090681 Authors: Pedro J. Zufiria Iker Barriales-Valbuena Time evolving Random Network Models are presented as a mathematical framework for modelling and analyzing the evolution of complex networks. This framework allows the analysis over time of several network characterizing features such as link density, clustering coefficient, degree distribution, as well as entropy-based complexity measures, providing new insight on the evolution of random networks. First, some simple dynamic network models, based only on edge density, are analyzed to serve as a baseline reference for assessing more complex models. Then, a model that depends on network structure with the aim of reflecting some characteristics of real networks is also analyzed. Such model shows a more sophisticated behavior with two different regimes, one of them leading to the generation of high clustering coefficient/link density ratio values when compared with the baseline values, as it happens in many real networks. Simulation examples are discussed to illustrate the behavior of the proposed models.
    Electronic ISSN: 1099-4300
    Topics: Chemistry and Pharmacology , Physics
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  • 63
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    Publication Date: 2018-09-08
    Description: IJERPH, Vol. 15, Pages 1959: Reducing Stress and Promoting Social Integration of International Medical Students through a Tandem Program: Results of a Prospective-Program Evaluation International Journal of Environmental Research and Public Health doi: 10.3390/ijerph15091959 Authors: Anne Herrmann-Werner Florian Junne Felicitas Stuber Daniel Huhn Christoph Nikendei Tanja Seifried-Dübon Stephan Zipfel Rebecca Erschens Medical students, and especially international medical students (IMS), have been shown to experience more psychological distress than the general student population in Germany. In order to address these issues, a structured Tandem Program (TP) to reduce stress and foster social integration of IMS has been introduced at the Medical Faculty of Tuebingen. The Tandem Program was evaluated prospectively with perceived stress (PSQ-20) as the main outcome. Secondary outcomes were ‘motives to participate’ in the TP, ‘specific stressors’, and ‘experiences made’ during the program. Stress levels of IMS at the beginning of the program (t0) (M = 48.14, SD = 11.95) were higher than those of German participants (M = 39.33, SD = 8.31) (t (67) = −3.66, p < 0.001). At the end of the TP (t1), stress levels of international students were significantly lower than at t0. “Improved ability to work in a team” was seen as one of the most beneficial factors. The results indicate that tandem programs at medical faculties may be a promising curricular intervention towards reducing stress levels, improving integration of international students, and to enhance intercultural and team-oriented competencies in both international and national medical students.
    Print ISSN: 1661-7827
    Electronic ISSN: 1660-4601
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Medicine
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  • 64
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    Publication Date: 2018-09-08
    Description: IJERPH, Vol. 15, Pages 1957: In the Heart of the Amazon: Noncommunicable Diseases and Apolipoprotein E4 Genotype in the Riverine Population International Journal of Environmental Research and Public Health doi: 10.3390/ijerph15091957 Authors: Gabriela Arrifano Jacqueline Alvarez-Leite José Souza-Monteiro Marcus Augusto-Oliveira Ricardo Paraense Barbarella Macchi André Pinto Reinaldo Oriá José do Nascimento Maria Crespo-Lopez The Amazon River basin is the largest tropical forest in the world. Most of the Amazon belongs to Brazil, a developing country that currently faces huge challenges related to the consolidation of its universal healthcare system. Noncommunicable diseases (NCDs) are the leading cause of death in Brazil, accounting for 74% of all deaths, and NCDs are probably underestimated in Amazonian population because of their geographical isolation and the precariousness of riverine communities. Important risk factors, such as genetic susceptibility, remain undetermined in the riverine population. This study performed fasting blood sugar (FBS) and blood pressure measurements and investigated the presence of the ε4 allele of apolipoprotein E (APOE4) to determine the prevalence of diabetes, hypertension and the genetic risk of NCDs. FBS and APOE4 were measured in blood samples from 763 participants using spectrometry and real-time PCR; 67.5% showed altered measurements, and 57.9% had never been diagnosed or treated. Altered FBS was found in 28.3% of the participants, hypertension in 57.6% and APOE4 in 32.0%. The health profile of the riverine population appears to differ from that of urban population in the Amazon. Additional risk factors for NCDs, such as environmental contamination and nutritional transition, may contribute more than increased genetic susceptibility to the prevalence of altered FBS and hypertension. Our results will help guide the development of preventive strategies and governmental actions for more effective management of NCDs in the Amazon area.
    Print ISSN: 1661-7827
    Electronic ISSN: 1660-4601
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Medicine
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  • 65
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    Publication Date: 2018-09-08
    Description: IJERPH, Vol. 15, Pages 1954: Relationship between Photosynthetic Capacity and Microcystin Production in Toxic Microcystis Aeruginosa under Different Iron Regimes International Journal of Environmental Research and Public Health doi: 10.3390/ijerph15091954 Authors: Xun Wang Peifang Wang Chao Wang Jin Qian Tao Feng Yangyang Yang Blooms of harmful cyanobacteria have been observed in various water bodies across the world and some of them can produce intracellular toxins, such as microcystins (MCs), which negatively impact aquatic organisms and human health. Iron participates significantly in cyanobacterial photosynthesis and is proposed to be linked to MC production. Here, the cyanobacteria Microcystis aeruginosa was cultivated under different iron regimes to investigate the relationship between photosynthetic capacity and MC production. The results showed that iron addition increased cell density, cellular protein concentration and the Chl-a (chlorophyll-a) content. Similarly, it can also up–regulate photosynthetic capacity and promote MC–leucine–arginine (MC–LR) production, but not in a dose–dependent manner. Moreover, a significant positive correlation between photosynthetic capacity and MC production was observed, and electron transport parameters were the most important parameters contributing to the variation of intracellular MC–LR concentration revealed by Generalized Additive Model analysis. As the electron transport chain was affected by iron variation, adenosine triphosphate production was inhibited, leading to the alteration of MC synthetase gene expression. Therefore, it is demonstrated that MC production greatly relies on redox status and energy metabolism of photosynthesis in M. aeruginosa. In consequence, more attention should be paid to the involvement of photosynthesis in the regulation of MC production by iron variation in the future.
    Print ISSN: 1661-7827
    Electronic ISSN: 1660-4601
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Medicine
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  • 66
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    Publication Date: 2018-09-08
    Description: IJERPH, Vol. 15, Pages 1953: Nonlinear Granger Causality between Health Care Expenditure and Economic Growth in the OECD and Major Developing Countries International Journal of Environmental Research and Public Health doi: 10.3390/ijerph15091953 Authors: Liping Ye Xinping Zhang Differing from previous studies ignoring the nonlinear features, this study employs both the linear and nonlinear Granger causality tests to examine the complex causal relationship between health care expenditure and economic growth among 15 Organisation for Economic Co-operation and Development (OECD) and 5 major developing countries. Some interesting findings can be obtained as follows: (1) For Australia, Austria, and UK, linear and nonlinear Granger causality does not exist between them. A unidirectional linear or nonlinear causality running from economic growth to health care expenditure can be found for Ireland, Korea, Portugal, and India. For these seven countries, health or fiscal policy related to health spending will not have an impact on economic growth; (2) For Belgium, Norway, and Mexico, only a unidirectional linear causality runs from health care expenditure to economic growth, while bidirectional linear causality can be found for Canada, Finland, Iceland, New Zealand, Spain, Brazil, and South Africa. Especially for the US, China, and Japan, a unidirectional nonlinear causality exists from health spending to economic growth. To improve the quality of national health, life quality and happiness, these 13 countries should actively look to optimise policy related to health care expenditure, such as by enhancing the efficiency of health costs to promote sustainable economic development.
    Print ISSN: 1661-7827
    Electronic ISSN: 1660-4601
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Medicine
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  • 67
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    Publication Date: 2018-09-08
    Description: IJERPH, Vol. 15, Pages 1951: The Effect of Nordic Walking Training Combined with Vitamin D Supplementation on Postural Control and Muscle Strength in Elderly People—A Randomized Controlled Trial International Journal of Environmental Research and Public Health doi: 10.3390/ijerph15091951 Authors: Jan Mieszkowski Bartłomiej Niespodziński Andrzej Kochanowicz Anna Gmiat Krzysztof Prusik Katarzyna Prusik Jakub Kortas Ewa Ziemann Jędrzej Antosiewicz Nordic Walking (NW) and Vitamin D concentration (Vit D) alone have been shown to contribute to the health and performance of elderly people. However, the interaction between these two factors has yet to be explored. In this study 42 women over 60 years of age (69.02 ± 5.56 years) were recruited and divided in two NW groups: a high-intensity interval training group (HI-NW) and a moderate-intensity continuous training group (MI-NW). Individuals from each group completed a 12-week NW training program (3 times a week/2 hours) combined with randomized Vitamin D supplementation (HD = high dose: 4000 IU/day or LD = low dose: 800 IU/day). Body composition, postural control, muscle strength and Vitamin D serum concentration were measured twice; before and after the intervention. To investigate the interaction between supplementation and training a mixed-design analysis of variance (ANOVA) was performed. The HI-NW group, regardless of supplementation dose, increased their Vit D and elbow torque performance. On the other hand, in the MI-NW group the same Vit D outcome was seen only with HD supplementation and was also associated with increased leg muscle mass. In conclusion, beneficial effects of both HI-NW and MI-NW training regimes were seen. The impact of the dose supplementation on Vit D and body composition was related to the type of NW training.
    Print ISSN: 1661-7827
    Electronic ISSN: 1660-4601
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Medicine
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  • 68
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    Publication Date: 2018-09-08
    Description: IJGI, Vol. 7, Pages 368: Critical Review of Methods to Estimate PM2.5 Concentrations within Specified Research Region ISPRS International Journal of Geo-Information doi: 10.3390/ijgi7090368 Authors: Guangyuan Zhang Xiaoping Rui Yonglei Fan Obtaining PM2.5 data for the entirety of a research region underlies the study of the relationship between PM2.5 and human spatiotemporal activity. A professional sampler with a filter membrane is used to measure accurate values of PM2.5 at single points in space. However, there are numerous PM2.5 sampling and monitoring facilities that rely on data from only representative points, and which cannot measure the data for the whole region of research interest. This provides the motivation for researching the methods of estimation of particulate matter in areas having fewer monitors at a special scale, an approach now attracting considerable academic interest. The aim of this study is to (1) reclassify and particularize the most frequently used approaches for estimating the PM2.5 concentrations covering an entire research region; (2) list improvements to and integrations of traditional methods and their applications; and (3) compare existing approaches to PM2.5 estimation on the basis of accuracy and applicability.
    Electronic ISSN: 2220-9964
    Topics: Architecture, Civil Engineering, Surveying , Geosciences
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  • 69
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    Publication Date: 2018-09-08
    Description: IJGI, Vol. 7, Pages 369: GIS-Assisted Prediction and Risk Zonation of Wildlife Attacks in the Chitwan National Park in Nepal ISPRS International Journal of Geo-Information doi: 10.3390/ijgi7090369 Authors: Aleš Ruda Jaromír Kolejka Thakur Silwal Population growth forces the human community to expand into the natural habitats of wild animals. Their efforts to use natural sources often collide with wildlife attacks. These animals do not only protect their natural environment, but in the face of losing the potential food sources, they also penetrate in human settlements. The research was situated in the Chitwan National Park (CNP) in Nepal, and the aim of this study was to investigate possible geospatial connections between attacks of all kinds of animals on humans in the CNP and its surroundings between 2003 and 2013. The patterns of attacks were significantly uneven across the months, and 89% of attacks occurred outside the park. In total, 74% attacks occurred in the buffer zone forests and croplands within 1 km from the park. There was a strong positive correlation among the number of victims for all attacking animals with a maximum of one victim per 4 km2, except elephant and wild boar. The density of bear victims was higher where the tiger and rhino victims were lower, e.g., in the Madi valley. The data collected during this period did not show any signs of spatial autocorrelation. The calculated magnitude per unit area using the kernel density, together with purpose-defined land use groups, were used to determine five risk zones of wildlife attacks. In conclusion, it was found that the riskiest areas were locations near the forest that were covered by agricultural land and inhabited by humans. Our research results can support any local spatial decision-making processes for improving the co-existence of natural protection in the park and the safety of human communities living in its vicinity.
    Electronic ISSN: 2220-9964
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  • 70
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    Publication Date: 2018-09-08
    Description: Materials, Vol. 11, Pages 1657: Electromagnetic Shielding Effectiveness of Woven Fabrics with High Electrical Conductivity: Complete Derivation and Verification of Analytical Model Materials doi: 10.3390/ma11091657 Authors: Marek Neruda Lukas Vojtech In this paper, electromagnetic shielding effectiveness of woven fabrics with high electrical conductivity is investigated. Electromagnetic interference-shielding woven-textile composite materials were developed from a highly electrically conductive blend of polyester and the coated yarns of Au on a polyamide base. A complete analytical model of the electromagnetic shielding effectiveness of the materials with apertures is derived in detail, including foil, material with one aperture, and material with multiple apertures (fabrics). The derived analytical model is compared for fabrics with measurement of real samples. The key finding of the research is that the presented analytical model expands the shielding theory and is valid for woven fabrics manufactured from mixed and coated yarns with a value of electrical conductivity equal to and/or higher than σ = 244 S/m and an excellent electromagnetic shielding effectiveness value of 25–50 dB at 0.03–1.5 GHz, which makes it a promising candidate for application in electromagnetic interference (EMI) shielding.
    Electronic ISSN: 1996-1944
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
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  • 71
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    Publication Date: 2018-09-08
    Description: Remote Sensing, Vol. 10, Pages 1425: Hyperspectral Image Classification Based on Parameter-Optimized 3D-CNNs Combined with Transfer Learning and Virtual Samples Remote Sensing doi: 10.3390/rs10091425 Authors: Xuefeng Liu Qiaoqiao Sun Yue Meng Min Fu Salah Bourennane Recent research has shown that spatial-spectral information can help to improve the classification of hyperspectral images (HSIs). Therefore, three-dimensional convolutional neural networks (3D-CNNs) have been applied to HSI classification. However, a lack of HSI training samples restricts the performance of 3D-CNNs. To solve this problem and improve the classification, an improved method based on 3D-CNNs combined with parameter optimization, transfer learning, and virtual samples is proposed in this paper. Firstly, to optimize the network performance, the parameters of the 3D-CNN of the HSI to be classified (target data) are adjusted according to the single variable principle. Secondly, in order to relieve the problem caused by insufficient samples, the weights in the bottom layers of the parameter-optimized 3D-CNN of the target data can be transferred from another well trained 3D-CNN by a HSI (source data) with enough samples and the same feature space as the target data. Then, some virtual samples can be generated from the original samples of the target data to further alleviate the lack of HSI training samples. Finally, the parameter-optimized 3D-CNN with transfer learning can be trained by the training samples consisting of the virtual and the original samples. Experimental results on real-world hyperspectral satellite images have shown that the proposed method has great potential prospects in HSI classification.
    Electronic ISSN: 2072-4292
    Topics: Architecture, Civil Engineering, Surveying , Geography
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  • 72
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    Publication Date: 2018-09-08
    Description: Remote Sensing, Vol. 10, Pages 1423: WeedMap: A Large-Scale Semantic Weed Mapping Framework Using Aerial Multispectral Imaging and Deep Neural Network for Precision Farming Remote Sensing doi: 10.3390/rs10091423 Authors: Inkyu Sa Marija Popović Raghav Khanna Zetao Chen Philipp Lottes Frank Liebisch Juan Nieto Cyrill Stachniss Achim Walter Roland Siegwart The ability to automatically monitor agricultural fields is an important capability in precision farming, enabling steps towards more sustainable agriculture. Precise, high-resolution monitoring is a key prerequisite for targeted intervention and the selective application of agro-chemicals. The main goal of this paper is developing a novel crop/weed segmentation and mapping framework that processes multispectral images obtained from an unmanned aerial vehicle (UAV) using a deep neural network (DNN). Most studies on crop/weed semantic segmentation only consider single images for processing and classification. Images taken by UAVs often cover only a few hundred square meters with either color only or color and near-infrared (NIR) channels. Although a map can be generated by processing single segmented images incrementally, this requires additional complex information fusion techniques which struggle to handle high fidelity maps due to their computational costs and problems in ensuring global consistency. Moreover, computing a single large and accurate vegetation map (e.g., crop/weed) using a DNN is non-trivial due to difficulties arising from: (1) limited ground sample distances (GSDs) in high-altitude datasets, (2) sacrificed resolution resulting from downsampling high-fidelity images, and (3) multispectral image alignment. To address these issues, we adopt a stand sliding window approach that operates on only small portions of multispectral orthomosaic maps (tiles), which are channel-wise aligned and calibrated radiometrically across the entire map. We define the tile size to be the same as that of the DNN input to avoid resolution loss. Compared to our baseline model (i.e., SegNet with 3 channel RGB (red, green, and blue) inputs) yielding an area under the curve (AUC) of [background=0.607, crop=0.681, weed=0.576], our proposed model with 9 input channels achieves [0.839, 0.863, 0.782]. Additionally, we provide an extensive analysis of 20 trained models, both qualitatively and quantitatively, in order to evaluate the effects of varying input channels and tunable network hyperparameters. Furthermore, we release a large sugar beet/weed aerial dataset with expertly guided annotations for further research in the fields of remote sensing, precision agriculture, and agricultural robotics.
    Electronic ISSN: 2072-4292
    Topics: Architecture, Civil Engineering, Surveying , Geography
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  • 73
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    Publication Date: 2018-09-08
    Description: Remote Sensing, Vol. 10, Pages 1422: Forest Variable Estimation Using a High Altitude Single Photon Lidar System Remote Sensing doi: 10.3390/rs10091422 Authors: André Wästlund Johan Holmgren Eva Lindberg Håkan Olsson As part of the digitalization of the forest planning process, 3D remote sensing data is an important data source. However, the demand for more detailed information with high temporal resolution and yet still being cost efficient is a challenging combination for the systems used today. A new lidar technology based on single photon counting has the possibility to meet these needs. The aim of this paper is to evaluate the new single photon lidar sensor Leica SPL100 for area-based forest variable estimations. In this study, it was found that data from the new system, operated from 3800 m above ground level, could be used for raster cell estimates with similar or slightly better accuracy than a linear system, with similar point density, operated from 400 m above ground level. The new single photon counting lidar sensor shows great potential to meet the need for efficient collection of detailed information, due to high altitude, flight speed and pulse repetition rate. Further research is needed to improve the method for extraction of information and to investigate the limitations and drawbacks with the technology. The authors emphasize solar noise filtering in forest environments and the effect of different atmospheric conditions, as interesting subjects for further research.
    Electronic ISSN: 2072-4292
    Topics: Architecture, Civil Engineering, Surveying , Geography
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  • 74
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    Publication Date: 2018-09-08
    Description: Remote Sensing, Vol. 10, Pages 1421: FVI—A Floating Vegetation Index Formed with Three Near-IR Channels in the 1.0–1.24 μm Spectral Range for the Detection of Vegetation Floating over Water Surfaces Remote Sensing doi: 10.3390/rs10091421 Authors: Bo-Cai Gao Rong-Rong Li Through the analysis of hyperspectral imaging data collected over water surfaces covered by floating vegetation, such as Sargassum and algae, we observed that the spectra commonly contain a reflectance peak centered near 1.07 μm. This peak results from the competing effects between the well-known vegetation reflectance plateau in the 0.81–1.3 μm spectral range and the absorption effects above 0.75 μm by liquid water within the vegetation and in the surrounding water bodies. In this article, we propose a new index, namely the floating vegetation index (FVI), for the hyperspectral remote sensing of vegetation over surface layers of oceans and inland lakes. In the formulation of the FVI, one channel centered near 1.0 μm and another 1.24 μm are used to form a linear baseline. The reflectance value of the third channel centered at the 1.07-μm reflectance peak above the baseline is defined as the FVI. Hyperspectral imaging data acquired with the AVIRIS (Airborne Visible Infrared Imaging Spectrometer) instrument over the Gulf of Mexico and over salt ponds near Moffett Field in southern portions of the San Francisco Bay were used to demonstrate the success in detecting Sargassum and floating algae with this index. It is expected that the use of this index for the global detection of floating vegetation from hyperspectral imaging data to be acquired with future satellite sensors will result in improved detection and therefore enhanced capability in estimating primary production, a measure of how much carbon is fixed per unit area per day by oceans and inland lakes.
    Electronic ISSN: 2072-4292
    Topics: Architecture, Civil Engineering, Surveying , Geography
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  • 75
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    Publication Date: 2018-09-08
    Description: Remote Sensing, Vol. 10, Pages 1424: Assessment of Forest above Ground Biomass Estimation Using Multi-Temporal C-band Sentinel-1 and Polarimetric L-band PALSAR-2 Data Remote Sensing doi: 10.3390/rs10091424 Authors: Xiaodong Huang Beth Ziniti Nathan Torbick Mark J. Ducey Synthetic Aperture Radar (SAR), as an active sensor transmitting long wavelengths, has the advantages of working day and night and without rain or cloud disturbance. It is further able to sense the geometric structure of forests more than passive optical sensors, making it a valuable tool for mapping forest Above Ground Biomass (AGB). This paper studies the ability of the single- and multi-temporal C-band Sentinel-1 and polarimetric L-band PALSAR-2 data to estimate live AGB based on ground truth data collected in New England, USA in 2017. Comparisons of results using the Simple Water Cloud Model (SWCM) on both VH and VV polarizations show that C-band reaches saturation much faster than the L-band due to its limited forest canopy penetration. The exhaustive search multiple linear regression model over the many polarimetric parameters from PALSAR-2 data shows that the combination of polarimetric parameters could slightly improve the AGB estimation, with an adjusted R2 as high as 0.43 and RMSE of around 70 Mg/ha when decomposed Pv component and Alpha angle are used. Additionally, the single- and multi-temporal C-band Sentinel-1 data are compared, which demonstrates that the multi-temporal Sentinel-1 significantly improves the AGB estimation, but still has a much lower adjusted R2 due to the limitations of the short wavelength. Finally, a site-level comparison between paired control and treatment sites shows that the L-band aligns better with the ground truth than the C-band, showing the high potential of the models to be applied to relative biomass change detection.
    Electronic ISSN: 2072-4292
    Topics: Architecture, Civil Engineering, Surveying , Geography
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  • 76
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    Publication Date: 2018-09-08
    Description: Energies, Vol. 11, Pages 2368: Novel Design Support Methodology Based on a Multi-Criteria Decision Analysis Approach for Energy Efficient District Retrofitting Projects Energies doi: 10.3390/en11092368 Authors: Miguel Á. García-Fuentes Rubén García-Pajares Cecilia Sanz Alberto Meiss Districts can be considered as a system of complex interconnections, interactions, relationships and flows. Therefore, a comprehensive approach is essential for effective decision-making with regards to energy efficiency improvement. When addressing interventions with a wider scale, the range of possible interventions is greater, as well as the possibilities of new business models to make bankable the interventions. However certain barriers can appear linked to the interactions among stakeholders, which are usually more complex than when tackling individual actuations. To overcome these barriers it is necessary to establish integrated and systemic methodologies able to support stakeholders to implement better collaboration approaches and carry out more informed decisions. These decisions should be based on a set of relevant indicators, calculated at district level, capturing the different stages that form the retrofitting process (from the diagnosis to the final assessment). This paper presents a holistic design methodology based on the application of a Multi-Criteria Decision Making approach that allows designing optimised solutions. This methodology is based on the evaluation of a set of District Sustainability Indicators while proposing an Integrated Project Delivery method improving the communications among stakeholders and, therefore, the decision-making process.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 77
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    Publication Date: 2018-09-08
    Description: Energies, Vol. 11, Pages 2366: Cyclic Assessment of Magnesium Oxide with Additives as a Thermochemical Material to Improve the Mechanical Strength and Chemical Reaction Energies doi: 10.3390/en11092366 Authors: Taesu Yim Hong Soo Kim Jae Yong Lee Heat storage with a thermochemical reaction has the advantages of a high heat storage density and no heat loss compared to conventional methods such as the sensible and latent heat. This method is promising to use in a thermal energy network because it is an efficient solution which addresses the time mismatch problem with regard to heat production and consumption. In this paper, we investigated Magnesium oxide (MgO) with different additives as a thermochemical material (TCM) coupled with the effects of several additives in an effort to improve the structural strength and reaction rate and reduce the initiation time. As additives in an MgO composite, Bentonite, Magnesium sulfate (MgSO4), and Zeolite 13X were chosen. With a cyclic scheduling experimental setup for the heat charging and discharging of the MgO composites, Bentonite as an additive improved the structural strength, and Zeolite 13X enhanced the reaction rate and led to faster reactions compared to only MgO as a TCM. With MgSO4 as an additive, however, the TCM composite showed a high reactivity during the a few cycles, and then rapidly became inactive due to byproducts side reaction. The results indicated that Bentonite and Zeolite additives, in an MgO composite, as a TCM can improve the mechanical strength and chemical reaction, optimum ratio is necessary to compromise promoting the thermochemical reaction.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 78
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    In: Sensors
    Publication Date: 2018-09-08
    Description: Sensors, Vol. 18, Pages 2999: Intrinsic Sensing Properties of Chrysotile Fiber Reinforced Piezoelectric Cement-Based Composites Sensors doi: 10.3390/s18092999 Authors: Jianlin Luo Chunwei Zhang Lu Li Baolin Wang Qiuyi Li Kwok L. Chung Chao Liu Lead-zirconate-titanate (PZT) nanoscale powder was first synthesized by the sol-gel method, then PZT and 0–3 type PZT/chrysotile fiber (CSF)/cement composite (PZTCC) wafers were fabricated after grind-mixing PZT powder with strontium carbonate and/or cement, ductile CSF in tandem with press-sintered process, respectively. The crystal structure (XRD), microstructure (SEM), piezoelectric properties after surface silver penetration, and polarization of the PZT and PZTCC wafer were investigated. Furthermore, self-sensing responses under either impulse or cyclic loading and micro-hardness toughness of PZTCC were also investigated. Results show that the incorporation of CSF and cement admixture weakens the perovskite crystalline peak of PZTCC; reduces the corresponding piezoelectric coefficient from 119.2 pC/N to 32.5 pC/N; but effectively bridges the gap on the toughness between PZTCC and concrete since the corresponding microhardness with 202.7 MPa of PZTCC is close to that of concrete. A good linear and fast electrical response against either impulse or cyclic loading of the PZTCC is achieved with their respective sensitivity, linearity, and repeatability to 1.505 mV/N, 2.42%, and 2.11%. The sensing responses and toughness of PZTCC is encouraging as an intrinsic piezoelectric sensor for real-time health monitoring of ductile concrete structures.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 79
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    MDPI Publishing
    In: Sensors
    Publication Date: 2018-09-08
    Description: Sensors, Vol. 18, Pages 2998: Analysis of the Subdivision Errors of Photoelectric Angle Encoders and Improvement of the Tracking Precision of a Telescope Control System Sensors doi: 10.3390/s18092998 Authors: Jiawei Yu Qiang Wang Guozhong Zhou Dong He Yunxia Xia Xiang Liu Wenyi Lv Yongmei Huang Photoelectric angle encoders, working as position sensors, have a great influence on the accuracy and stability of telescope control systems (TCS). In order to improve the tracking precision of TCS, a method based on subdivision error compensation for photoelectric angle encoders is proposed. First, a mathematical analysis of six types of subdivision errors (DC error, phase error, amplitude error, harmonic error, noise error, and quantization error) is presented, which is different from the previously used analysis based on the Lissajous figure method. In fact, we believe that a mathematical method is more efficient than the figure method for the expression of subdivision errors. Then, the distribution law and period length of each subdivision error are analyzed. Finally, an error compensation algorithm is presented. In a real TCS, the elevation jittering phenomenon occurs, which indicates that compensating for the amplitude error is necessary. A feed-forward loop is then introduced into the TCS, which is position loop- and velocity loop-closed, leading to a decrease of the tracking error by nearly 54.6%, from 2.31” to 1.05”, with a leading speed of 0.25°/s, and by 40.5%, from 3.01” to 1.79”, with a leading speed of 1°/s. This method can realize real-time compensation and improve the ability of TCS without any change of the hardware. In addition, independently of the environment and the kind of control strategy used, this method can also improve the tracking precision presumably because it compensates the measuring error inside the photoelectric angle encoder.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 80
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    MDPI Publishing
    In: Sensors
    Publication Date: 2018-09-08
    Description: Sensors, Vol. 18, Pages 2996: PEDOT:PSS-Based Temperature-Detection Thread for Wearable Devices Sensors doi: 10.3390/s18092996 Authors: Jin-Woo Lee Dong-Cheul Han Han-Jae Shin Se-Hyeok Yeom Byeong-Kwon Ju Wanghoon Lee In this research, we developed a wearable temperature-sensing element by dip dyeing threads in poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) (p-type conducting polymer) solution. The PEDOT:PSS was used to dye the textile and it exhibited negative temperature coefficient characteristics in which the resistance decreases as the temperature increases. The fabricated temperature-detection thread achieved a sensitivity of 167.1 Ω/°C with 99.8% linearity in the temperature range of −50 °C to 80 °C. We anticipate that temperature sensors that apply our technology will be made as stitch- or textile-type for wearable devices, and they will be widely adopted for different applications such as in fitness, leisure, healthcare, medical treatment, infotainment, industry, and military applications, among others.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 81
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    MDPI Publishing
    In: Entropy
    Publication Date: 2018-09-08
    Description: Entropy, Vol. 20, Pages 685: Constructal Optimization for Cooling a Non-Uniform Heat Generating Radial-Pattern Disc by Conduction Entropy doi: 10.3390/e20090685 Authors: Jiang You Huijun Feng Lingen Chen Zhihui Xie A heat conduction model in a radial-pattern disc by considering non-uniform heat generation (NUHG) is established in this paper. A series of high conductivity channels (HCCs) are attached on the rim of the disc and extended to its center. Constructal optimizations of the discs with constant and variable cross-sectional HCCs are carried out, respectively, and their maximum temperature differences (MTDs) are minimized based on analytical method and finite element method. Besides, the influences of the NUHG coefficient, HCC number and width coefficient on the optimal results are studied. The results indicate that the deviation of the optimal constructs obtained from the analytical method and finite element method are comparatively slight. When the NUHG coefficient is equal to 10, the minimum MTD of the disc with 25 constant cross-sectional HCCs is specifically reduced by 48.8% compared to that with 10 HCCs. As a result, the heat conduction performance (HCP) of the disc can be efficiently improved by properly increasing the number of HCCs. The minimum MTD of the disc with variable cross-sectional HCC is decreased by 15.0% when the width coefficient is changed from 1 to 4. Therefore, the geometry of variable cross-sectional HCC can be applied in the constructal design of the disc to a better heat transfer performance. The constructal results obtained by investigating the non-uniform heat generating case in this paper can contribute to the design of practical electronic device to a better heat transfer performance.
    Electronic ISSN: 1099-4300
    Topics: Chemistry and Pharmacology , Physics
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  • 82
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    MDPI Publishing
    In: Entropy