bluuebunny/crossref_metadata_2025 huggingface dataset:
Electrocardiographic Fragmented Activity (II): A Machine Learning Approach to Detection
Authors: Melgarejo-Meseguer Francisco-Manuel , Gimeno-Blanes Francisco-Javier , Salar-Alcaraz María-Eladia , Gimeno-Blanes Juan-Ramón , Martínez-Sánchez Juan , García-Alberola Arcadi , Rojo-Álvarez José Luis
Published: September 2019

Hypertrophic cardiomyopathy, according to its prevalence, is a comparatively common disease related to the risk of suffering sudden cardiac death, heart failure and stroke. This illness is characterized by the excessive deposition of collagen among healthy myocardium cells. This situation, which is medically known as fibrosis, constitutes effective conduction obstacles in the myocardium electrical path, and when severe enough, it can be outlined as additional peaks or notches in the QRS, clinically entitled as fragmentation. Nowadays, the fragmentation detection is performed by visual inspection, but the fragmented QRS can be confused with the noise present in the electrocardiogram (ECG). On the other hand, fibrosis detection is performed by magnetic resonance imaging with late gadolinium enhancement, the main drawback of this technique being its cost in terms of time and money. In this work, we propose two automatic algorithms, one for fragmented QRS detection and another for fibrosis detection. For this purpose, we used four different databases, including the subrogated database described in the companion paper and incorporating three additional ones, one compounded by more accurate subrogated ECG signals and two compounded by real and affected subjects as labeled by expert clinicians. The first real-world database contains QRS fragmented records and the second one contains records with fibrosis and both were recorded in Hospital Clínico Universitario Virgen de la Arrixaca (Spain). To deeply analyze the scope of these datasets, we benchmarked several classifiers such as Neural Networks, Support Vector Machines (SVM), Decision Trees and Gaussian Naïve Bayes (NB). For the fragmentation dataset, the best results were 0.94 sensitivity, 0.88 specificity, 0.89 positive predictive value, 0.93 negative predictive value and 0.91 accuracy when using SVM with Gaussian kernel. For the fibrosis databases, more limited accuracy was reached, with 0.47 sensitivity, 0.91 specificity, 0.82 predictive positive value, 0.66 negative predictive value and 0.70 accuracy when using Gaussian NB. Nevertheless, this is the first time that fibrosis detection is attempted automatically from ECG postprocessing, paving the way towards improved algorithms and methods for it. Therefore, we can conclude that the proposed techniques could offer a valuable tool to clinicians for both fragmentation and fibrosis diagnoses support.
An Environmental Perception Framework for Robotic Fish Formation Based on Machine Learning Methods
Authors: Li Shuman , Yang Wenjing , Xu Liyang , Li Chao
Published: September 2019

Autonomous Underwater Vehicle (AUV) has become a hotspot in the field of robot in recent years. As a special kind of AUV, the robotic fish can achieve better propulsion efficiency and maneuverability than traditional AUVs. Studies show that robotic fish formation can save energy and perform more complex tasks than single robotic fish, but it is difficult to maintain a stable formation because the nearby environmental condition is hard to obtain. Inspired by the lateral line system (LLS) of fish, this paper constructs a predictive model of flow velocity and a judgement model of spacing between individual platforms for robotic fish formation through monitoring sensors on robotic fish surface. The models are built by methods of polynomial fitting and neural networks based on Computational Fluid Dynamics (CFD) simulation. The results show that the flow velocity predicted by our model could reduce the error to 0.4 % , and the spacing judgement accuracy could reach at least 80%. The findings are useful for maintaining a stable formation and will provide significant guidance for the control of robotic fish formation and sensor installation position on the robotic fish surface.
Fatigue Cracking Resistance of Engineered Cementitious Composites (ECC) under Working Condition of Orthotropic Steel Bridge Decks Pavement
Authors: Zhao Yanjing , Jiang Jiwang , Ni Fujian , Zhou Lan
Published: September 2019

In order to investigate the fatigue cracking resistance of engineered cementitious composites (ECC) used in in total life pavement, the semi-circular bending (SCB) test and improved three-point bending fatigue test (ITBF) were utilized in this study. The digital image correlation (DIC) method was also utilized to track the surface strain fields of specimens during the SCB test. X-ray computed tomography (CT) and digital image processing (DIP) technologies were applied to measure the internal-crack distribution of the ITBF specimen. The results of the SCB test showed that the fatigue cracking damage process of ECC can be divided into three stages and that the cracking stable propagating stages occupied the main part, which indicates that ECC has excellent ductility and toughness and could work very well with existing cracks. The ITBF results showed that the fatigue cracking resistance of ECC was better than epoxy asphalt concrete (EAC). In addition, the internal-crack distribution along the depth direction of the ITBF specimen could be presented well by the image pixel statistical (IPS) method based on CT scanning of image slices. It could be found that multiple cracks propagate simultaneously in ECC, instead of a single crack, under the OSBD pavement working condition.
An End-to-End Deep Learning Image Compression Framework Based on Semantic Analysis
Authors: Wang Cheng , Han Yifei , Wang Weidong
Published: September 2019

Lossy image compression can reduce the bandwidth required for image transmission in a network and the storage space of a device, which is of great value in improving network efficiency. With the rapid development of deep learning theory, neural networks have achieved great success in image processing. In this paper, inspired by the diverse extent of attention in human eyes to each region of the image, we propose an image compression framework based on semantic analysis, which creatively combines the application of deep learning in the field of image classification and image compression. We first use a convolutional neural network (CNN) to semantically analyze the image, obtain the semantic importance map, and propose a compression bit allocation algorithm to allow the recurrent neural network (RNN)-based compression network to hierarchically compress the image according to the semantic importance map. Experimental results validate that the proposed compression framework has better visual quality compared with other methods at the same compression ratio.
A Numerical Evaluation of SIFs of 2-D Functionally Graded Materials by Enriched Natural Element Method
Authors: Cho Jin-Rae
Published: September 2019

This paper presents the numerical prediction of stress intensity factors (SIFs) of 2-D inhomogeneous functionally graded materials (FGMs) by an enriched Petrov-Galerkin natural element method (PG-NEM). The overall trial displacement field was approximated in terms of Laplace interpolation functions, and the crack tip one was enhanced by the crack-tip singular displacement field. The overall stress and strain distributions, which were obtained by PG-NEM, were smoothened and improved by the stress recovery. The modified interaction integral M ˜ ( 1 , 2 ) was employed to evaluate the stress intensity factors of FGMs with spatially varying elastic moduli. The proposed method was validated through the representative numerical examples and the effectiveness was justified by comparing the numerical results with the reference solutions.
Ultrathin Acoustic Metasurface Holograms with Arbitrary Phase Control
Authors: Wang Huaping , Gao Weijie , Zhu Rongrong , Wang Zehao , Xu Zhiwei , Zheng Bin
Published: September 2019

Holograms show great potential in optical or acoustical waves applications due to their capability to reconstruct images. In this paper, we propose a novel scheme to realize acoustic holograms based on an ultrathin metasurface with arbitrary phase control ability. Compared with the conventional imaging method, e.g., concave mirror, which has a bulky size and limited imaging effects, the acoustic metasurface comprises a single layer of Helmholtz-like elements that can largely reduce the complexity of production. With this ultrathin reflective metasurface, acoustic holograms are constructed through a subtle structure design for single and multiple focal imaging, while the potential thermoviscous effects are minimized. We further demonstrate that the metasurface has the capability of arbitrary phase control in a certain frequency range, where the reflected phase dispersion is linear. Our proposed ultrathin metasurface holograms would be very useful in numerous applications, such as acoustic sensing, medical imaging, and so on.
Coupling Effect of Space-Arrangement and Wall Thermal Resistance on Indoor Thermal Environment of Passive Solar Single-Family Building in Tibet
Authors: Cui Xiaoling , Zhang Yangkai , Sang Guochen , Wang Wenkang , Zhu Yiyun , Zhang Lei
Published: September 2019

In areas where solar energy is abundant, such as the Tibetan plateau, passive solar buildings are attracting more and more attention and becoming a popular form of rural building. However, it is often difficult to achieve the satisfactory indoor thermal environment in a local rural passive solar single-family house. In order to improve the indoor thermal environment of passive solar buildings through building design, a systematic study of rural single-family buildings in Tibet was conducted. The basic parameters were investigated on the outdoor thermal environment, space-arrangement, envelope structure, and the indoor thermal environment. The building model considering space-arrangement modes was developed based on the survey data in multi-space passive solar buildings. The general physical and mathematical analysis models of multi-space passive solar buildings were established based on the heat transfer theory. Furthermore, the effects of space-arrangement and exterior wall thermal resistance on indoor air temperature were analyzed by numerical simulation. Results show that the indoor air temperature of the passive solar building is influenced by space-arrangement and wall thermal resistance together. When the space-arrangement of the building model was changed from “north-south through type” (mode a) to “through and separation combination” (mode b) and “north-south separation” (mode c), the indoor air temperature of the living room increased from 8.8 °C to 10.6 °C and 11.6 °C, with increases of 20.5% and 31.8%, respectively. In addition, equally increasing the thermal resistance of exterior walls in different orientations has different effects on the indoor air temperature. In the space-arrangement mode c, comparing with the temperature increment of the living room and bedroom caused by increasing thermal resistance of the south wall and north wall, the temperature increment of the living room caused by increasing thermal resistance of the east/west wall increased by 151.7% and 32.7%, and that of the bedroom increased by 609.1% and 239.1% respectively. This study can provide a reference for the optimal design of passive solar buildings in solar energy abundant areas.
Experience from Integrated Air Quality Management in the Mexico City Metropolitan Area and Singapore
Authors: Molina Luisa T. , Velasco Erik , Retama Armando , Zavala Miguel
Published: September 2019

More than half of the world’s population now lives in cities as a result of unprecedented urbanization during the second half of the 20th century. The urban population is projected to increase to 68% by 2050, with most of the increase occurring in Asia and Africa. Population growth and increased energy consumption in urban areas lead to high levels of atmospheric pollutants that harm human health, cause regional haze, damage crops, contribute to climate change, and ultimately threaten the society’s sustainability. This article reviews the air quality and compares the policies implemented in the Mexico City Metropolitan Area (MCMA) and Singapore and offers insights into the complexity of managing air pollution to protect public health and the environment. While the differences in the governance, economics, and culture of the two cities greatly influence the decision-making process, both have made much progress in reducing concentrations of harmful pollutants by implementing comprehensive integrated air quality management programs. The experience and the lessons learned from the MCMA and Singapore can be valuable for other urban centers, especially in the fast-growing Asia-Pacific region confronting similar air pollution problems.
Subseasonal Influences of Teleconnection Patterns on the Boreal Wintertime Surface Air Temperature over Southern China as Revealed from Three Reanalysis Datasets
Authors: Shi Ning , Zhang Dongdong , Wang Yicheng , Tajie Suolang
Published: September 2019

The daily fields from three reanalysis datasets are utilized to explore the subseasonal influence of teleconnection patterns on the surface air temperature (SAT) over southern China. Due to the similarity of the results from the different datasets, the ensemble mean is then used in this study. After applying the false discovery rate to the significance test, the composite results reveal that positive Western Pacific (WP) events, East Atlantic (EA) events, Scandinavian (SCA) events, and Eastern Atlantic/Western Russia (EAWR) events are the teleconnection events that have an influence on SAT anomalies over southern China. The timing of inducing significant SAT anomalies over southern China is similar among positive WPevents, EA events and EAWR events, i.e., approximately the first 5-day period after their peak day. In contrast, SCA events exert a lagged significant influence on SAT, i.e., during approximately the second 6-day period after their peak day. Therefore, considering that significant circulation anomalies generally begin to appear at least 4 days before the peak day, these teleconnection events could be used as subseasonal predictors for SAT anomalies over southern China.
Incremental Capacity Analysis-Based Impact Study of Diverse Usage Patterns on Lithium-Ion Battery Aging in Electrified Vehicles
Authors: Huang Meng
Published: September 2019

Aging assessment is critical for lithium-ion batteries (LIBs) as the technology of choice for energy storage in electrified vehicles (EVs). Existing research is mainly focused on either increasing modeling precision or improving algorithm efficiency, while the significance of data applied for aging assessment has been largely overlooked. Moreover, reported studies are mostly confined to a specific condition without considering the impacts of diverse usage patterns on battery aging, which is practically challenging and can greatly affect battery degradation. This paper addresses these issues through incremental capacity (IC) analysis, which can both utilize data directly available from on-board sensors and interpret degradations from a physics-based perspective. Through IC analysis, the optimal health feature (HF) and the state of charge (SOC)-based optimal data profile for battery aging assessment have been identified. Four stress factors, i.e., depth-of-discharge (DOD), charging C-rate, operating mode, and temperature, have been selected to jointly characterize diverse usage patterns. Impact analysis of different stress factors through the optimal HF with the SOC-based optimal data profile from aging campaign experiments have generated practical guidance on usage patterns to improve battery health monitoring and lifetime control strategies.
Surface Area to Volume Ratio of Electrospun Polydioxanone Templates Regulates the Adsorption of Soluble Proteins from Human Serum
Authors: Fetz Allison E. , Fantaziu Cristina A. , Smith Richard A. , Radic Marko Z. , Bowlin Gary L.
Published: September 2019

Neutrophils, the first cells that interact with surface-adsorbed proteins on biomaterials, have been increasingly recognized as critical maestros in the foreign body response for guided tissue regeneration. Recent research has shown that small diameter (SD) fibers of electrospun tissue regeneration templates, which have a high surface area to volume ratio (SAVR), enhance the release of neutrophil extracellular traps (NETs) compared to large diameter (LD) fibers, resulting in impaired tissue regeneration. In this study, we evaluated the adsorption of eight human serum proteins on the surface of electrospun templates to investigate how protein adsorption may regulate the release of NETs. Electrospun polydioxanone templates made from SD fibers with high SAVR and LD fibers with low SAVR, were incubated with 0.2% human serum and in situ protein adsorption was quantified with infrared-based immunodetection. Of the detected proteins, IgM and vitronectin adsorbed at low levels, suggesting that they do not play a central role in the release of NETs. Contrastingly, albumin and IgG adsorbed rapidly to the surface of the templates. One-hundred to 200 times more IgG adsorbed on the templates compared to albumin, with significantly greater adsorption occurring on the SD templates with high SAVR. Given that neutrophils express receptors that interact with IgG during phagocytosis and NET release, these results suggest that SAVR-dependent adsorption of IgG on the SD electrospun templates may contribute to the up-regulated release of NETs. Overall, this study may aid in the design of immunomodulatory biomaterials that regulate NET release and thus the potential for neutrophil-driven tissue regeneration.
Raw Bowl Tea (Tuocha) Polyphenol Prevention of Nonalcoholic Fatty Liver Disease by Regulating Intestinal Function in Mice
Authors: Liu Bihui , Zhang Jing , Sun Peng , Yi Ruokun , Han Xiaoyan , Zhao Xin
Published: September 2019

A high-fat diet-induced C57BL/6N mouse model of non-alcoholic fatty liver disease (NAFLD) was established. The effect and mechanism of Raw Bowl Tea polyphenols (RBTP) on preventing NAFLD via regulating intestinal function were observed. The serum, liver, epididymis, small intestine tissues, and feces of mice were examined by biochemical and molecular biological methods, and the composition of RBTP was analyzed by HPLC assay. The results showed that RBTP could effectively reduce the body weight, liver weight, and liver index of NAFLD mice. The serum effects of RBTP were: (1) decreases in alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (AKP), total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL-C), D-lactate (D-LA), diamine oxidase (DAO), lipopolysaccharide (LPS), and an increase of high density lipoprotein cholesterol (HDL-C) levels; (2) a decrease of inflammatory cytokines such as interleukin 1 beta (IL-1β), interleukin 4 (IL-4), interleukin 6 (IL-6), interleukin 10 (IL-10), tumor necrosis factor alpha (TNF-α), and interferon gamma (INF-γ); (3) a decrease the reactive oxygen species (ROS) level in liver tissue; and (4) alleviation of pathological injuries of liver, epididymis, and small intestinal tissues caused by NAFLD and protection of body tissues. qPCR and Western blot results showed that RBTP could up-regulate the mRNA and protein expressions of LPL, PPAR-α, CYP7A1, and CPT1, and down-regulate PPAR-γ and C/EBP-α in the liver of NAFLD mice. In addition, RBTP up-regulated the expression of occludin and ZO-1, and down-regulated the expression of CD36 and TNF-α in the small intestines of NAFLD mice. Studies on mice feces showed that RBTP reduced the level of Firmicutes and increased the minimum levels of Bacteroides and Akkermansia, as well as reduced the proportion of Firmicutes/Bacteroides in the feces of NAFLD mice, which play a role in regulating intestinal microecology. Component analysis showed that RBTP contained seven polyphenolic compounds: Gallic acid, (-)-epigallocatechin, catechin, L-epicatechin, (-)-epigallocatechin gallate, (-)-gallocatechin gallate, and (-)-epicatechin gallate (ECG), and high levels of caffeine, (-)-epigallocatechin (EGC), and ECG. RBTP improved the intestinal environment of NAFLD mice with the contained active ingredients, thus playing a role in preventing NAFLD. The effect was positively correlated with the dose of 100 mg/kg, which was even better than that of the clinical drug bezafibrate.
Preparation, Characterization, and Inhibition of Hyaluronic Acid Oligosaccharides in Triple-Negative Breast Cancer
Authors: Han Wenwei , Song Lili , Wang Yingdi , Lv Youjing , Chen Xiangyan , Zhao Xia
Published: September 2019

Hyaluronic acid (hyaluronan, HA) is a critical component of the extracellular matrix and plays an important biological function of interacting with different molecules and receptors. In this study, both odd- and even-numbered HA oligosaccharides (HAOs) with specific degrees of polymerization (DP) were prepared by different hydrochloric acid hydrolyses, and their structures were characterized by means of HPLC, ESI-MS, and NMR. The data show that the odd-numbered HAOs (DP3-11) have a glucuronic acid reducing end, while the even-numbered HAOs (DP2-10) have an N-acetylglucosamine reducing end. Biological evaluations indicated that all HAOs significantly inhibited the growth and migration of triple-negative breast cancer (TNBC) MDA-MB-231 cells. Among these oligosaccharides, the HA tetrasaccharide (DP4) was confirmed to be the minimum fragment necessary to inhibit MDA-MB-231 cells. Our data suggest that HAOs have potential value in the treatment of TNBC.
Evaluation of In-Flow Magnetoresistive Chip Cell—Counter as a Diagnostic Tool
Authors: Giraud Manon , Delapierre François-Damien , Wijkhuisen Anne , Bonville Pierre , Thévenin Mathieu , Cannies Gregory , Plaisance Marc , Paul Elodie , Ezan Eric , Simon Stéphanie , Fermon Claude , Féraudet-Tarisse Cécile , Jasmin-Lebras Guénaëlle
Published: September 2019

Inexpensive simple medical devices allowing fast and reliable counting of whole cells are of interest for diagnosis and treatment monitoring. Magnetic-based labs on a chip are one of the possibilities currently studied to address this issue. Giant magnetoresistance (GMR) sensors offer both great sensitivity and device integrability with microfluidics and electronics. When used on a dynamic system, GMR-based biochips are able to detect magnetically labeled individual cells. In this article, a rigorous evaluation of the main characteristics of this magnetic medical device (specificity, sensitivity, time of use and variability) are presented and compared to those of both an ELISA test and a conventional flow cytometer, using an eukaryotic malignant cell line model in physiological conditions (NS1 murine cells in phosphate buffer saline). We describe a proof of specificity of a GMR sensor detection of magnetically labeled cells. The limit of detection of the actual system was shown to be similar to the ELISA one and 10 times higher than the cytometer one.
Unique Aberrations in Intimal Sarcoma Identified by Next-Generation Sequencing as Potential Therapy Targets
Authors: Roszik Jason , Khan Abir , Conley Anthony P. , Livingston J. Andrew , Groisberg Roman , Ravi Vinod , Carmagnani Pestana Roberto , Sen Shiraj , Subbiah Vivek
Published: September 2019

Intimal sarcomas are rare and histologically heterogeneous tumors, commonly arising from the pulmonary arteries. They have remained challenging to treat. Few studies in the literature study the genomics of this cancer. Identifying targetable alterations is an important step in advancing the treatment of intimal sarcomas. Using data from the American Association for Cancer Research Project Genomics Evidence Neoplasia Information Exchange (AACR GENIE) database, we cataloged genetic alterations and assessed their clinical utility from thirteen patients with intimal sarcoma. Notable copy number alterations included amplification in MDM2, CDK4, PDGFRA, and NOTCH2, as well as copy number losses in CDKN2A and CDKN2B. Actionable alterations included mutations in ATM/ATR, PTCH1, and PDGFRB. Moreover, genomic rearrangement events, specifically PDE4DIP-NOTCH2 and MRPS30-ARID2 fusions were identified. Co-occurring alterations included a NOTCH2 copy number gain in the PDE4DIP-NOTCH2 fusion positive tumor and PDGFRB mutations in both fusion-positive cases. Our study suggests that PDGFRB may be relevant in the tumorigenesis process. Including genomic profiling in the management of intimal sarcoma and potential enrollment in targeted therapy trials is warranted.
Electron Beam Induced Enhancement of the Catalytic Properties of Ion-Track Membranes Supported Copper Nanotubes in the Reaction of the P-Nitrophenol Reduction
Authors: Mashentseva Anastassiya A. , Shlimas Dmitriy I. , Kozlovskiy Artem L. , Zdorovets Maxim V. , Russakova Alyona V. , Kassymzhanov Murat , Borisenko Alexander N.
Published: September 2019

This study considers the effect of various doses of electron irradiation on the crystal structure and properties of composite catalysts based on polyethylene terephthalate track-etched membranes and copper nanotubes. Copper nanotubes were obtained by electroless template synthesis and irradiated with electrons with 3.8 MeV energy in the dose range of 100–250 kGy in increments of 50 kGy. The original and irradiated samples of composites were investigated by X-ray diffraction technique (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The improved catalytic activity of composite membranes with copper nanotubes was demonstrated by the example of the reduction reaction of p-nitrophenol in the presence of sodium borohydride. Irradiation with electrons at doses of 100 and 150 kGy led to reaction rate constant increases by 35 and 59%, respectively, compared to the non-irradiated sample. This enhancing catalytic activity could be attributed to the changing of the crystallite size of copper, as well as the surface roughness of the composite membrane.
Critical Material Applications and Intensities in Clean Energy Technologies
Authors: Leader Alexandra , Gaustad Gabrielle
Published: September 2019

Clean energy technologies have been developed to address the pressing global issue of climate change; however, the functionality of many of these technologies relies on materials that are considered critical. Critical materials are those that have potential vulnerability to supply disruption. In this paper, critical material intensity data from academic articles, government reports, and industry publications are aggregated and presented in a variety of functional units, which vary based on the application of each technology. The clean energy production technologies of gas turbines, direct drive wind turbines, and three types of solar photovoltaics (silicon, CdTe, and CIGS); the low emission mobility technologies of proton exchange membrane fuel cells, permanent-magnet-containing motors, and both nickel metal hydride and Li-ion batteries; and, the energy-efficient lighting devices (CFL, LFL, and LED bulbs) are analyzed. To further explore the role of critical materials in addressing climate change, emissions savings units are also provided to illustrate the potential for greenhouse gas emission reductions per mass of critical material in each of the clean energy production technologies. Results show the comparisons of material use in clean energy technologies under various performance, economic, and environmental based units.
Strategies for Enhancing the Low Wind Speed Performance of H-Darrieus Wind Turbine—Part 1
Authors: Mohan Kumar Palanisamy , Sivalingam Krishnamoorthi , Lim Teik-Cheng , Ramakrishna Seeram , Wei He
Published: September 2019

Small wind turbines are key devices for micro generation in particular, with a notable contribution to the global wind energy sector. Darrieus turbines, despite being highly efficient among various types of vertical axis turbines, received much less attention due to their starting characteristics and poor performance in low wind speeds. Radically different concepts are proposed as a potential solution to enhance the performance of Darrieus turbine in the weak wind flows, all along the course of Darrieus turbine development. This paper presents a comprehensive review of proposed concepts with the focus set on the low wind speed performance and critically assessing their applicability based on economics, reliability, complexity, and commercialization aspects. The study is first of its kind to consolidate and compare various approaches studied on the Darrieus turbine with the objective of increasing performance at low wind. Most of the evaluated solutions demonstrate better performance only in the limited tip speed ratio, though they improve the low wind speed performance. Several recommendations have been developed based on the evaluated concepts, and we concluded that further critical research is required for a viable solution in making the Darrieus turbine a low speed device.
Adoption of Grid-Tie Solar System at Residential Scale
Authors: Chand Aneesh A. , Prasad Kushal A. , Mamun Kabir A. , Sharma Krishneel R. , Chand Kritish K.
Published: September 2019

Traditionally, remote and urban communities worldwide have been supplied electricity almost completely by fossil fuel generators to accommodate for electricity needs. Currently, the integration of renewable energy sources (RESs) into the current power generation systems can offer attractive economic and environmental merits, including considerable fuel savings and carbon dioxide emission reductions. In relation to sustainability, efficiency and economic feasibility, solar photovoltaic (PV) is one of the most promising sources of RESs which is being touted as a leading solution to long-term electrification and development problems in rural and urban parts of Pacific Island Countries (PICs). In this work, a grid-tie PV system is instigated at a residential scale. The idea of this research is not to claim the power output from the PV system but to show the feasibility of a grid-tie system at a residential scale. This will help the PICs, non-profit organisations and the government better share scarce resources towards achieving their energy goals and be in line with Sustainable Development Goal (SDG) 7, ensuring access to affordable, reliable, sustainable and modern energy for all.
Sustainability Assessment of Cotton-Based Textile Wet Processing
Authors: Kabir S M Fijul , Chakraborty Samit , Hoque S M Azizul , Mathur Kavita
Published: September 2019

The textile and fashion industries account for a significant part of global business. Textile wet processing (TWP) is a crucial stage in textile manufacturing. It imparts aesthetics as well as functional appeal on the textile fabric and ultimate products. Nevertheless, it is considered as one of the most polluting industries and threatens sustainability. There have been different approaches to transform this polluting industry to a sustainable industry. Many researchers have found this challenging, as sustainable, eco-friendly, green or cleaner wet processing might not be always applicable and relevant from the perspective of industrial applications. The present work helps us understand the current state of research of cotton-based textile processes including proposed sustainable approaches. It also examines the achievement of the degree of sustainability of those proposed processes with the lens of the triple bottom line (TBL) framework, identifies existing limitations, and suggests future research scopes that might pave ways for young researchers to learn and undertake new experimental and theoretical research.
Climate Change Adaptation in Natural World Heritage Sites: A Triage Approach
Authors: Perry Jim
Published: September 2019

Climate change is a certainty, but the degree and rate of change, as well as impacts of those changes are highly site-specific. Natural World Heritage sites represent a treasure to be managed and sustained for all humankind. Each World Heritage site is so designated on the basis of one or more Outstanding Universal Values. Because climate change impacts are site-specific, adaptation to sustain Universal Values also must be specific. As such, climate change adaptation is a wicked problem, with no clear action strategies available. Further, adaptation resources are limited at every site. Each site management team must decide which adaptations are appropriate investments. A triage approach guides that evaluation. Some impacts will be so large and/or uncertain that the highest probability of adaptation success comes from a series of uncertain actions that reduce investment risk. Others will be small, certain, comfortable and yet have low probable impact on the Universal Value. A triage approach guides the management team toward highest probable return on investment, involving stakeholders from the surrounding landscape, advancing engagement and communication, and increasing transparency and accountability.
Development of a Stainless Austenitic Nitrogen-Alloyed CrMnNiMo Spring Steel
Authors: Schröder Christina , Wendler Marco , Kreschel Thilo , Volkova Olena , Weiß Andreas
Published: September 2019

The generation of a nickel-reduced, stainless spring steel strip with a thickness of 0.2 mm, producible under industrial conditions, is the aim of a transfer project together with the Institute of Metal Forming/TU BAF and the Auerhammer Metallwerk GmbH within the DFG Collaborative Research Centre (CRC) 799. The spring steel strip should exhibit a tensile strength of ≥1700 MPa in work-hardened and partitioned state. The mechanical and corrosive properties of the steel strip should be equal or better than those given for 1.4310 steel (AISI 301). The article presents the results of laboratory alloys focused on the design of steel strips, which meet the requirements for a cost-effective production. The results presented relate to steel design, microstructure formation, temperature-dependent mechanical properties, and corrosion resistance. Four alloys of the type X5CrMnNiMoN16-x-4 with manganese contents of approximately 2 to 6 wt.-percent were investigated. The austenitic steel X5CrMnNiMoN16-4-4 with TRIP/TWIP effect was selected for deformation and partitioning treatments. Its deformation-induced α’-martensite formation significantly contributes to the work hardening of the steel. A short-time annealing treatment (partitioning) further increases the strength properties.
Microbiological and Clinical Aspects of Cervicofacial Actinomyces Infections: An Overview
Authors: Gajdács Márió , Urbán Edit , Terhes Gabriella
Published: September 2019

Similarly to other non-spore-forming Gram-positive anaerobes, members of the Actinomyces genus are important saprophytic constituents of the normal microbiota of humans. Actinomyces infections are considered to be rare, with cervicofacial infections (also known as ‘lumpy jaw syndrome’) being the most prevalent type in the clinical practice. Actinomycoses are characterized by a slowly progressing (indolent) infection, with non-specific symptoms, and additionally, the clinical presentation of the signs/symptoms can mimic other pathologies, such as solid tumors, active Mycobacterium tuberculosis infections, nocardiosis, fungal infections, infarctions, and so on. The clinical diagnosis of actinomycosis may be difficult due to its non-specific symptoms and the fastidious, slow-growing nature of the pathogens, requiring an anaerobic atmosphere for primary isolation. Based on 111 references, the aim of this review is to summarize current advances regarding the clinical features, diagnostics, and therapy of cervicofacial Actinomyces infections and act as a paper for dentistry specialists, other physicians, and clinical microbiologists.
A Multi-User Encryption and Authentication System Based on Joint Transform Correlation
Authors: Zhao Tieyu , Chi Yingying
Published: September 2019

Optical image encryption technology based on joint transform correlation (JTC) has attracted increasing attention from researchers. We propose a multi-user secure communication system based on the special properties of JTC. Multiple users utilize their own fingerprints to encrypt the plain-text in the encryption process, and each user must be first authenticated at the beginning of the decryption process. Only users with legitimate identities can perform the decryption process, whereas unauthorized users with false identities cannot, so the security of the system is greatly improved. Furthermore, we propose a multi-user double-image encryption method, which can better meet the needs of different security environments. Considering the possibility of overlapping images at the output end, we prove that a JTC-based image encryption system can avoid overlapping images at the output when the distance between the input images is 3W (W is the side length of a square image), which provides a theoretical foundation for further research. Finally, a numerical simulation demonstrates the effectiveness and feasibility of the proposed idea.
Thermodynamic Implications of Multiquintessence Scenario
Authors: Jawad Abdul , Khan Zoya , Rani Shamaila , Bamba Kazuharu
Published: September 2019

In this paper, we discuss the validity of the generalized second law of thermodynamics in the presence of a multi-component scalar field ( ϕ ) in a spatially flat Friedmann-Robertson-Walker (FRW) universe. We describe the first-order formalism by defining the Hubble parameter as H = − W ( ϕ i ) . By using three super-potential models of the Hubble parameter, we analyze the validity of the generalized law and thermal equilibrium conditions in the presence of the logarithmically-corrected, Bekenstein-Hawking, Sharma-Mittal and R e ´ n y i entropies. It is noticed that the generalized law and thermal equilibrium conditions hold for some cases.
Information Theoretic Multi-Target Feature Selection via Output Space Quantization
Authors: Sechidis Konstantinos , Spyromitros-Xioufis Eleftherios , Vlahavas Ioannis
Published: September 2019

A key challenge in information theoretic feature selection is to estimate mutual information expressions that capture three desirable terms—the relevancy of a feature with the output, the redundancy and the complementarity between groups of features. The challenge becomes more pronounced in multi-target problems, where the output space is multi-dimensional. Our work presents an algorithm that captures these three desirable terms and is suitable for the well-known multi-target prediction settings of multi-label/dimensional classification and multivariate regression. We achieve this by combining two ideas—deriving low-order information theoretic approximations for the input space and using quantization algorithms for deriving low-dimensional approximations of the output space. Under the above framework we derive a novel criterion, Group-JMI-Rand, which captures various high-order target interactions. In an extensive experimental study we showed that our suggested criterion achieves competing performance against various other information theoretic feature selection criteria suggested in the literature.
Investigation of Induced Charge Mechanism on a Rod Electrode
Authors: Li Jiming , Li Jingyu , Cheng Xuezhen , Feng Guojin
Published: September 2019

Rod electrodes based on an electrostatic induction mechanism are widely used in various industrial applications, but the analytic solution of an induced charge mechanism on a metal rod electrode has not yet been systematically established. In this paper, the theoretical model of the induced charge on a rod electrode is obtained through the method of images. Then, the properties of the rod electrode under the action of the point charge are studied, including the induced charge density distribution on the rod electrode, the amount of the induced charge with different diameters and lengths of the electrode, and the effective space region induced by the electrode. On this basis, a theoretical model of the induced current on a rod electrode is established, which is used to study the induced current properties by a moving point charge. It is found that both the magnitude and bandwidth of the induced current increase with the increased point charge velocity. Finally, three experimental studies are conducted, and the experimental results show good consistency with the analysis of the theoretical model, verifying the correctness, and accuracy of the model. In addition, the induced charge mechanism studied in this paper can act as an effective basis for the rod electrode sensor design in terms of the optimal radius and length.
Electromagnetic Analysis and Performance Investigation of a Flux-Switching Permanent Magnet Machine
Authors: Azeem Muhammad , Kim Byungtaek
Published: September 2019

This paper aims to present a general and effective analytical approach to calculate the air gap flux density and the back electromotive force (EMF) of a flux-switching permanent magnet (FSPM) machine. The proposed analytical expression of the air gap flux density is based on an improved air gap permeance function considering the geometries of slotted stator core pieces and magnets between stator teeth as well as the salient rotor poles. The back EMF equation is accurately derived using the proposed air gap flux density equation expressed in terms of practical machine dimensions and thus it provides the key design factors as well as details of the back EMF production mechanism. To validate the proposed analytical expressions, they are applied to the case study of a 12-slot 10-pole FSPM machine, and the finite element analysis results confirm the analytical predictions. Besides, for the proposed analytical model, the effects of the machine’s geometries on back EMF characteristics are investigated. The investigation shows that the ratio of rotor slot opening to slot pitch has a significant effect on the back EMF, and its optimal value is suggested. The proposed equations also provide a mean to choose the slot and pole combinations to obtain a higher power density.
Simulation of Partial Discharge Induced EM Waves Using FDTD Method—A Parametric Study
Authors: Loubani Alaa , Harid Noureddine , Griffiths Huw , Barkat Braham
Published: September 2019

This paper reports the results of a parametric study on the characteristics of electromagnetic (EM) waves propagated due to surface- and cavity-type partial discharges (PD) in materials using the finite-difference time domain (FDTD) method. First, the EM waves emitted by such discharges in material samples were measured using a broadband aperture antenna. The measurements showed that the frequency range of the measured signals lay within the ultra-high frequency (UHF) range, suggesting that by carefully choosing the UHF antenna characteristics and its location it might be possible to apply this method to characterize the PD-emitted waves; and hence, to potentially use it to detect and monitor PD defects. In this context, the FDTD simulations were used here to simulate the experimental set-up and examine the propagation characteristics of EM waves emitted by such discharges under uniform and non-uniform test electrode configurations. Using an approximation of the exciting PD current pulses, the electromagnetic field components and the voltage signals captured on a simulated monopole sensor were computed in the time domain at various locations. To explore the limits of the application of the UHF method for detecting these PD types, a parametric study was carried out to clarify how the captured signals are influenced by the PD intensity, the frequency content of the exciting PD pulse, the type of insulation material, the dimensions and the position of the UHF antenna. One of the challenges that needs further investigation is the accurate simulation of the actual PD current pulse produced by such discharges, and hence its frequency content, as there is limited or no measured data available. The results showed that while the amplitude of the captured EM signals increase with the PD intensity, no appreciable signal is detected when the PD pulse width is higher than about 4ns, which may not occur often in unbounded air insulated systems. Equally important is the location and orientation of the UHF sensor—the results showed improved sensitivity when the sensor is vertically polarized and placed in close proximity in the lateral direction with reference to the discharge path.
Flow Boiling in Minigap in the Reversed Two-Phase Thermosiphon Loop
Authors: Klugmann Michał , Dąbrowski Paweł , Mikielewicz Dariusz
Published: September 2019

The paper presents the results of experimental investigations of a model of a heat exchanger featuring a minigap, which is perceived as an evaporator for an inverted thermosiphon. The system works with a single component test fluid. The tested evaporator generates pumping power in the test loop in a way similar to the mammoth pump. The tests regarded a module of the heat exchanger, consisting of a hot leg and a cold leg with the width by the length of 0.1 × 0.2 m, heated by a uniform heat flux. In the tests, the minigaps of 1, 2 and 3 mm were formed. Two fluids, namely, distilled water and ethanol, were tested in the facility. Two-phase flow structures for both working fluids and various operational parameters, together with comprehensive visualization material, are presented. The specifics of pressure changes and its influence on operating parameters and flow structure are discussed.
Dynamics and Management of Rising Outbreak Spruce Budworm Populations
Authors: Régnière Jacques , Cooke Barry , Béchard Ariane , Dupont Alain , Therrien Pierre
Published: September 2019

Management of spruce budworm, Choristoneura fumiferana (Clem.), outbreak spread requires understanding the demographic processes occurring in low, but rising populations. For the first time, detailed observations were made in the early stages of outbreak development. We sampled populations over a three-year period in both treated and untreated populations in the Lower St-Lawrence region of Quebec, Canada, and measured the density-dependence of survival and population growth rates, and the impact of natural enemies and insecticides. Insecticides tested were Bacillus thuringiensis (Berliner 1915) and tebufenozide. We recorded strong density-dependence of survival between early larval stages and adult emergence, explained largely by the variation of natural enemy impacts and overcrowding. We also observed inverse density-dependence of apparent fecundity: net immigration into lower-density populations and net emigration from the higher, linked to a threshold of ~25% defoliation. Because of high migration rates, none of the 2013 treatments reduced egg populations at the end of summer. However lower migration activity in 2014 allowed population growth to be reduced in treated plots. This evidence lends support to the conclusion that, for a budworm population to increase to outbreak density, it must be elevated via external perturbations, such as immigration, above a threshold density of ~4 larvae per branch tip (L4). Once a population has increased beyond this threshold, it can continue growing and itself become a source of further spread by moth migration. These findings imply that populations can be brought down by insecticide applications to a density where mortality from natural enemies can keep the reduced population in check, barring subsequent immigration. While we recognize that other factors may occasionally cause a population to exceed the Allee threshold and reach outbreak level, the preponderance of immigration implies that if all potential sources of significant numbers of moths are reduced on a regional scale by insecticide applications, a widespread outbreak can be prevented, stopped or slowed down by reducing the supply of migrating moths.