bluuebunny/crossref_metadata_2025 huggingface dataset:
Empirical Role Of Salivary Parameters In Diagnosis Of Type Ii Diabetes Mellitus – “A Case Control Study”.
Authors: Gouthami Tunuguntla , Kollata Sushuma , Kosuru venkata krishnam raju , Reddy Ambica , Bommireddy Simha Vikram
Published: June 2019

Background:

Diabetes mellitus a chronic disorder, poses a major health problem today. In diabetes, there is a considerable alteration in the composition of saliva, these alterations can be analysed and possibly evaluated in early detection of diabetes.

Aim of the study:
The aim of this study is to determine and compare the serum and salivary glucose levels, salivary amylase and total salivary protein concentrations, and to determine if salivary analytes can be a biomarker in detection of diabetes.

Materials and methods:
The present study includes a total of 80 individuals, with 40 type 2 diabetics and 40 age matched healthy controls. Diabetic status was assessed by random blood glucose levels. Unstimulated saliva from groups I and II was collected from each participant and analysed for glucose, amylase and total protein levels. Serum and Salivary glucose estimation was performed using glucose-oxidase end point assay method, amylase by direct substrate kinetic enzymatic method and total protein by pyrogallol red dye method.

Results:

A significantly higher salivary glucose (5.823 ± 2.035 mg/dl), salivary amylase (370.3 ± 243 u/l) and lower total proteins (73.4 ± 26.3 mg/dl) were observed in type 2 diabetics compared to salivary glucose ((1.1 ± 0.4409 mg/dl)), salivary amylase (128.8± 54.93 u/l) and higher total proteins (92.46 ± 25.17 mg/dl) in controls.

Conclusion:

These results suggest that diabetes influences the composition of saliva and also suggests that salivary analytes can be used as a diagnostic tool in the early detection of diabetes.

Key Words: Diabetes mellitus, glucose, salivary total protein, salivary amylase.
Muscadine (Vitis rotundifolia Michx., syn. Muscandinia rotundifolia (Michx.) Small): The Resilient, Native Grape of the Southeastern U.S
Authors: Hickey Cain C. , Smith Erick D. , Cao Shanshan , Conner Patrick
Published: June 2019

Angiosperms are well adapted to tolerate biotic and abiotic stresses in their native environment. However, the growth habit of native plants may not be suited for cultivation and their fruits may not be desirable for consumption. Adapting a plant for cultivation and commercial appeal through breeding and selection may accentuate weaknesses in pest tolerance. The transition of muscadine from a wild, native plant to a cultivated crop has taken place over the last 150 years. Early production primarily involved cloning elite wild selections; few pest management inputs were needed since the material was genetically similar to the native plant. Over time, emphasis was placed on the refinement of pruning, trellising, and other cultural inputs to increase productivity and commercial implementation. In turn, breeders developed newer cultivars with greater productivity and commercial appeal. Many modern muscadine cultivars remain tolerant to biotic pests and are adapted to a hot and humid climate. The primary focus of this review is to provide a descriptive context of muscadine as a native American, perennial fruit crop that requires minimal pest management in hot, humid climates relative to recently introduced European bunch grapes. Inherent muscadine traits resulting in fewer pesticide inputs make them worthy of being planted across considerable acreages; yet, muscadines remain a niche crop. We conclude that muscadines suffer from their short history of cultivation in a confined region and would benefit from breeding and marketing efforts to increase consumption, commercial acceptance, and awareness.
Addressing Animal Welfare through Collaborative Stakeholder Networks
Authors: Fernandes Jill , Blache Dominique , Maloney Shane K. , Martin Graeme B. , Venus Bronwyn , Walker Frederick Rohan , Head Brian , Tilbrook Alan
Published: June 2019

In this review, we discuss animal welfare as a complex and contested issue facing society and outline why collaborative, multi-stakeholder approaches are critical for effective policy development. Using the lens of “wicked problems” and drawing upon governance literature on policy networks, we identify important factors for working with the inherent complexity of animal welfare through the inclusion of various stakeholder perspectives. We present two case studies that illustrate policy network approaches to animal welfare and highlight the value of fostering collaboration among various stakeholder groups from the industry, community, research, and government sectors. We suggest that the influence of stakeholder networks will likely increase in coming years as newer forms of participatory governance become common. By understanding how collaborative stakeholder networks establish participatory governance, productive communication, and collective priorities, leaders in the field of animal welfare can more productively engage with stakeholders and achieve long-lasting improvements in animal welfare.
Effects of Environmental Enrichment on Pig Welfare—A Review
Authors: Godyń Dorota , Nowicki Jacek , Herbut Piotr
Published: June 2019

Good husbandry conditions on farms is of key importance for assuring animal welfare. One of the most important legal documents regulating the rules of maintaining pigs is the Directive 2008/120/EC, which states that group-housed pigs should have access to litter or other materials that provide exploration and occupation. Released in 2016, the Commission Recommendation (EU) 2016/336 on the application of the Council Directive 2008/120/EC characterizes the various categories of materials that may be used to improve animal welfare. According to the document, straw is considered as an optimal material for pig housing, however, materials categorized as suboptimal (e.g., wood bark) and materials of marginal interest (e.g., plastic toys) are often used in practice and scientific research. As such, the aim of this paper is to review and systematize the current state of knowledge on the topic of the impact of environmental enrichment on pig welfare. This article raises mainly issues, such as the effectiveness of the use of various enrichment on the reduction of undesirable behavior—tail biting; aggression; and stereotypies at the pre-weaning, post-weaning, and fattening stage of pig production.
Characterization of the Normal Portal and Hepatic Blood Flow of Adult Holstein-Friesian Cows
Authors: Barreiro-Vázquez J. Daniel , Miranda Marta , Barreiro-Vilanova M. Isabel , Diéguez F. Javier , Barreiro-Lois Andrés
Published: June 2019

In the past, hepatic blood flow in cows was invasively characterized to investigate different pathologies and physiological conditions. However, hepatic blood flow can be easily evaluated with transabdominal Doppler ultrasound. Sixteen healthy adult non-lactating, non-pregnant Holstein-Friesian cows were examined using B-mode and Doppler ultrasound between the right flank and 9th intercostal space to establish the best approach to the different parts of the portal and hepatic vein systems, and determine normal blood flow characteristics. The main portal vein was characterized by a turbulent, high-velocity flow due to the opposing confluence of the splenic and cranial mesenteric veins, while hepatic and caudal vena cava veins have laminar blood flow, in which the phasicity is considered mainly respiratory in origin. Reference values were determined in relation to the anatomical point of observation. In conclusion, transabdominal Doppler ultrasound of the portal system is a simple technique that allows non-invasive characterization of portal and hepatic blood haemodynamics in cows.
Effect of Acute Ingestion of Green Tea Extract and Lemon Juice on Oxidative Stress and Lipid Profile in Pigs Fed a High-Fat Diet
Authors: Fang Xi , Azain Michael , Crowe-White Kristi , Mumaw Jennifer , Grimes Janet A. , Schmiedt Chad , Barletta Michele , Rayalam Srujana , Park Hea Jin
Published: June 2019

Green tea and its catechins have been shown to ameliorate high fat diet-induced oxidative stress and hyperlipidemia. However, low bioavailability of catechins limits their therapeutic potential. Lemon juice (LJ) has been suggested to enhance the bioavailability of catechins in vitro. This study investigated the antioxidative and hypolipidemic efficacy of a single dose of green tea extract (GTE) or GTE plus LJ (GTE + LJ) in high-fat diet fed pigs. Sixteen pigs ingested a single dose of GTE (190 mg/kg/day) or GTE + LJ (0.75 mL/kg/day) mixed with low-fat (LF; 5% fat) or high-fat (HF; 22% fat) diets and blood samples were collected for 24 h. Plasma catechin level peaked at two hours, and gradually returned to baseline after six hours following the intake. The addition of LJ significantly increased plasma catechin level. The diet containing GTE did not lower plasma cholesterol and triacylglycerol (TG) concentrations, superoxide dismutase (SOD) and catalase activity, or malondialdehyde concentration in 24 h in HF-fed pigs. Addition of a single dose of LJ, however, significantly decreased plasma TG level in LF groups but did not cause further changes on any other markers compared to the GTE alone. Our findings indicate limited effect of a single meal containing GTE on plasma antioxidant enzymes, lipid profile, and lipid peroxidation in pigs and no significant synergistic/additive action of adding LJ to GTE within 24 h in pigs. A study with a longer treatment period is warranted to further understand the potential role of GTE in reducing HF diet-induced oxidative stress and the possible synergistic role of LJ.
A Method to Detect Type 1 Diabetes Based on Physical Activity Measurements Using a Mobile Device
Authors: Czmil Anna , Czmil Sylwester , Mazur Damian
Published: June 2019

Type 1 diabetes is a chronic disease marked by high blood glucose levels, called hyperglycemia. Diagnosis of diabetes typically requires one or more blood tests. The aim of this paper is to discuss a non-invasive method of type 1 diabetes detection, based on physical activity measurement. We solved a binary classification problem using a variety of computational intelligence methods, including non-linear classification algorithms, which were applied and comparatively assessed. Prediction of disease presence among children and adolescents was evaluated using performance measures, such as accuracy, sensitivity, specificity, precision, the goodness index, and AUC. The most satisfying results were obtained when using the random forest method. The primary parameters in disease detection were weekly step count and the weekly number of vigorous activity minutes. The dependance between the weekly number of steps and the type 1 diabetes presence was established after an insightful analysis of data using classification and clustering algorithms. The findings have shown promising results that type 1 diabetes can be diagnosed using physical activity measurement. This is essential regarding the non-invasiveness and flexibility of the detection method, which can be tested at any time anywhere. The proposed technique can be implemented on a mobile device.
Research on the Modeling, Control, and Calibration Technology of a Tracked Vehicle Load Simulation Test Bench
Authors: Lv Haoliang , Zhou Xiaojun , Yang Chenglong , Wang Zhe , Fu Yimeng
Published: June 2019

The load simulation test bench plays an important role in tracked vehicle development. The stability and accuracy of the system have a vital impact on the experimental results. To accurately reproduce the power performance of a tracked vehicle on the test platform, this paper aims to investigate the model, control, and calibration method of the test bench. Firstly, the dynamic model of a tracked vehicle under complex driving conditions is analyzed and established, which takes driving torque as the input and driving wheel speed as the output. Then, considering the uncertainties and disturbances in the system model, a 2-degree-of-freedom (2-DOF) control method combined with a disturbance observer is proposed to solve the stability problem of the system. Furthermore, in order to investigate the accuracy of the simulation on the test bed, a method of calibrating the system by a flywheel set with standard inertia is proposed. In the calibration process, the influence of the system resistance torque and the original mechanical inertia on the results is considered, and the response time of the inertia simulation is analyzed in both a steady and dynamic state. Finally, the load simulation test is carried out with the corrected system. The test results show that the system has a high load simulation accuracy under various load simulation tests.
Efficient Weights Quantization of Convolutional Neural Networks Using Kernel Density Estimation based Non-uniform Quantizer
Authors: Seo Sanghyun , Kim Juntae
Published: June 2019

Convolutional neural networks (CNN) have achieved excellent results in the field of image recognition that classifies objects in images. A typical CNN consists of a deep architecture that uses a large number of weights and layers to achieve high performance. CNN requires relatively large memory space and computational costs, which not only increase the time to train the model but also limit the real-time application of the trained model. For this reason, various neural network compression methodologies have been studied to efficiently use CNN in small embedded hardware such as mobile and edge devices. In this paper, we propose a kernel density estimation based non-uniform quantization methodology that can perform compression efficiently. The proposed method performs efficient weights quantization using a significantly smaller number of sampled weights than the number of original weights. Four-bit quantization experiments on the classification of the ImageNet dataset with various CNN architectures show that the proposed methodology can perform weights quantization efficiently in terms of computational costs without significant reduction in model performance.
Energy Enhancement and Energy Spread Compression of Electron Beams in a Hybrid Laser-Plasma Wakefield Accelerator
Authors: Wu Ying , Yu Changhai , Qin Zhiyong , Wang Wentao , Zhang Zhijun , Qi Rong , Feng Ke , Ke Lintong , Chen Yu , Wang Cheng , Yang Xiaojun , Leng Yuxin , Liu Jiansheng , Li Ruxin , Xu Zhizhan
Published: June 2019

We experimentally demonstrated the generation of narrow energy-spread electron beams with enhanced energy levels using a hybrid laser-plasma wakefield accelerator. An experiment featuring two-color electron beams showed that after the laser pump reached the depletion length, the laser-wakefield acceleration (LWFA) gradually evolved into the plasma-driven wakefield acceleration (PWFA), and thereafter, the PWFA dominated the electron acceleration. The energy spread of the electron beams was further improved by energy chirp compensation. Particle-in-cell simulations were performed to verify the experimental results. The generated monoenergetic high-energy electron beams are promising to upscale future accelerator systems and realize monoenergetic γ -ray sources.
Developing a Library of Shear Walls Database and the Neural Network Based Predictive Meta-Model
Authors: Moradi Mohammad Javad , Hariri-Ardebili Mohammad Amin
Published: June 2019

There is a large amount of useful information from past experimental tests, which are usually ignored in test-setup for the new ones. Variation of assumptions, materials, test procedures, and test objectives make it difficult to choose the right model for validation of the numerical models. Results from different experiments are sometimes in conflict with each other, or have minimum correlation. Furthermore, not all these information are easily accessible for researchers and engineers. Therefore, this paper presents the results of a comprehensive study on different experimental models for steel plate and reinforced concrete shear walls. A unique library of up to 13 parameters (mechanical properties and geometric characteristics) affecting the strength, stiffness and drift ratio of the shear walls are gathered including their sensitivity analysis. Next, a predictive meta-model is developed based on artificial neural network. It is capable of forecasting the responses for any desired shear wall with good accuracy. The proposed network can be used to as an alternative to the nonlinear numerical simulations or expensive experimental test.
Corrosion Behavior and Conductivity of TiNb and TiNbN Coated Steel for Metallic Bipolar Plates
Authors: Shi Kun , Li Xue , Zhao Yang , Li Wei-Wei , Wang Shu-Bo , Xie Xiao-Feng , Yao Li , Jensen Jens Oluf , Li Qing-Feng
Published: June 2019

To improve corrosion resistance and electronic conductivity of bipolar plates for proton exchange membrane fuel cell (PEMFC), coatings of TiNb and TiNbN on 316L stainless steel (SS) were prepared by magnetron sputtering. X-ray diffraction (XRD) measurements confirmed the existence of metallic nitrides in the TiNbN coating. Scanning electron microscope (SEM) tests showed that the deposited coatings provided smooth surfaces. Further electrochemical measurements indicated that the corrosion resistance of TiNb coating was significantly higher than that of substrate. At 0.19 V vs MSE, the long-term stabilized current density of TiNb/316L SS was lower than 1 μA·cm−2. The interfacial contact resistance (ICR) values between coating and carbon paper suggested that TiNb and TiNbN films had better contact conductivity than 316L SS substrate. In conclusion, TiNb coated 316L SS metallic bipolar plate material is a promising option for PEMFC.
Intergeneric Hybrid from Jatropha curcas L. and Ricinus communis L.: Characterization and Polyploid Induction
Authors: Premjet Duangporn , Obeng Abraham Kusi , Kongbangkerd Anupan , Premjet Siripong
Published: June 2019

Jatropha curcas L. (2n = 2× = 22) is increasingly attracting attention in the biodiesel industry for its oil. However, the cultivation of J. curcas L. is faced with numerous challenges unlike the cultivation of Ricinus communis L. (2n = 2× = 20), a closely related species. The generation of an intergeneric hybrid between J. curcas L. and R. communis L. was investigated. Intergeneric hybrids were produced by hand crossing. Immature embryos were rescued, in vitro, from the hybrid seeds and cultured on an enriched Murashige and Skoog (MS) medium for a month. The plantlets produced were grown in sterile peat moss in plastic pots and covered with polyethylene for 30 days, after which they were transferred into cement potted soil. The hybridity and the genuineness of the hybrids were successfully confirmed using randomly amplified polymorphic DNA (RAPD) markers. The number of branches, stem diameter, and leaf size of the F1 hybrids were similar to those of J. curcas L. while the plant height was similar to that of R. communis L. Young hybrids were treated with various concentrations (0%, 0.3%, 0.4%, and 0.5%) of colchicine to induce polyploids. The calli (JR6) treated with 0.3% colchicine recorded the highest tetraploid cell percentage (38.89%). A high tetraploid cell percentage (>50%) is significant in overcoming the problem of sterility after hybridization.
Function-Based and Multi-Scale Approach to Green Roof Guidelines for Urban Sustainability Transitions: The Case of Bogota
Authors: Ibáñez Gutiérrez R. Andrés , Ramos-Mejía Mónica
Published: June 2019

A growing number of local green roof niches across the globe are transitioning into the mainstream domain. Guidelines are key to this process, as they define technological environments and set the criteria for best practices in a given socio-technical setting. Although the German Forschungsgesellschaft Landschaftsentwicklung Landschaftsbau (FLL) cornerstone guidelines provided solid empirical ground and established technical parameters for the successful application of green roofs across continents, investigations about alternative green roof guidelines for emerging markets remain very scarce. The paper presents the inclusive approach followed by the Bogota Green Roof Guidelines, which were the result of a multi-actor participatory process that examined how to embrace a wide range of emerging green roof technologies and local adaptations while promoting quality of application at different scales, regardless of the system used, and despite the absence of local robust empirical data on performance parameters. As a result, Bogota’s Green Roof Guidelines incorporated ad hoc elements: (1) new definitions and taxonomy, (2) function-based contents, (3) multi-scale approach, and (4) performance scoping. These aspects are discussed to provide novel insights for the advancement of green infrastructure policies in diverse institutional settings aiming to promote quality and simultaneously support markets that make room for a wide variety of green infrastructure practices.
Mechanical Behavior of Porous Functionally Graded Nanocomposite Materials
Authors: Mota A. F. , Loja M. A. R.
Published: June 2019

Materials used in biomedical applications need to cope with a wide set of requisites, one of them being their structural adequacy to a specific application. Thus, it is important to understand their behavior under specified standard cases, namely concerning their structural performance. This objective constituted the focus of the present study, where nanocomposite functionally graded materials integrating different porosity distributions were analyzed. To this purpose a set of numerical simulations based on the finite element method, reproducing American Society for Testing and Materials (ASTM) tensile and bending tests were considered. The results obtained show a good performance of the models implemented through their preliminary verification. It is also possible to conclude that carbon nanotubes and porosity distributions provide different and opposite effects in the context of the nanocomposite materials analyzed.
Berberine Promotes Beige Adipogenic Signatures of 3T3-L1 Cells by Regulating Post-transcriptional Events
Authors: Lin Ying-Chin , Lee Yuan-Chii , Lin Ying-Ju , Lin Jung-Chun
Published: June 2019

Induced brown adipocytes (also referred to as beige cells) execute thermogenesis, as do the classical adipocytes by consuming stored lipids, being related to metabolic homeostasis. Treatment of phytochemicals, including berberine (BBR), was reported to induce conversion from white adipocytes to beige cells. In this study, results of microRNA (miRNA)-seq analyses revealed a decrease in miR-92a, of which the transcription is driven by the c13orf25 promoter in BBR-treated 3T3-L1 cells. BBR treatment manipulated the expressions of SP1 and MYC, in turn, reducing the activity of the c13orf25 promoter. A decrease in miR-92a led to an increase in RNA-binding motif protein 4a (RBM4a) expression, which facilitated the beige adipogenesis. Overexpression of miR-92a or depletion of RBM4a reversely interfered with the impact of BBR treatment on the beige adipogenic signatures, gene expressions, and splicing events in 3T3-L1 cells. Our findings demonstrated that BBR treatment enhanced beige adipogenesis of 3T3-L1 cells through transcription-coupled post-transcriptional regulation.
TiBCN-Ceramic-Reinforced Ti-Based Coating by Laser Cladding: Analysis of Processing Conditions and Coating Properties
Authors: Li Yuxin , Zhang Pengfei , Bai Peikang , Su Keqiang , Su Hongwen
Published: June 2019

In this paper, TiBCN-ceramic-reinforced Ti-based coating was fabricated on a Ti6Al4V substrate surface by laser cladding. The correlations between the main processing parameters and the geometrical characteristics of single clad tracks were predicted by linear regression analysis. On this basis, the microstructure, microhardness, corrosion resistance, and wear resistance of the coating and the substrate were investigated. The results showed that the clad height, clad width, clad depth, and dilution rate depended mainly on the laser power, the powder feeding rate, and the scanning speed. TiBCN-ceramic-reinforced Ti-based coating was mainly composed of directional dendritic TiBCN phases, equiaxed TiN phases, needle-like Al3Ti phases, and Ti phases. The microhardness gradually increased from the bottom to the top of the coating. The highest microhardness of coating was 1025 HV, which was three times higher than that of the Ti6Al4V substrate (350 HV). Furthermore, the coating exhibited excellent corrosion resistance and wear resistance. The corrosion potential (Ecorr) reached −1.258 V, and the corrosion density (Icorr) was 4.035 × 10−5 A/cm2, which was one order lower than that of the Ti6Al4V substrate (1.172 × 10−4 A/cm2). The coating wear mass loss was 4.35 mg, which was about two-third of the wear mass loss of the Ti6Al4V substrate (6.71 mg).
Simulation-Based Development of a New Cylindrical-Cavity Microwave-Plasma Reactor for Diamond-Film Synthesis
Authors: Wang Qijun , Wu Gai , Liu Sheng , Gan Zhiyin , Yang Bo , Pan Junheng
Published: June 2019

A 2.45 GHz microwave-plasma chemical-vapor deposition (MPCVD) reactor was designed and built in-house by collaborating with Guangdong TrueOne Semiconductor Technology Co., Ltd. A cylindrical cavity was designed as the deposition chamber and a circumferential coaxial-mode transformer located at the top of the cavity was adopted as the antenna. Two quartz-ring windows that were placed far away from the plasma and cooled by water-cooling cavity walls were used to affix the antenna to the cavity and act as a vacuum seal for the reactor, respectively. This design improved the sealing and protected the quartz windows. In addition, a numerical simulation was proposed to predict the electric-field and plasma-density distributions in the cavity. Based on the simulation results, a microwave-plasma reactor with TM021 mode was built. The leak rate of this new reactor was tested to be as low as 1 × 10−8 Pa·m3·s−1, and the maximal microwave power was as high as 10 kW. Then, single-crystal diamond films were grown with the morphology and crystalline quality characterized by an optical microscope, atomic force microscope (AFM), Raman spectrometer, photoluminescence (PL) spectrometer, and high-resolution X-ray diffractometer. It was shown that the newly developed MPCVD reactor can produce diamond films with high quality and purity.
Control Method for Phase-Shift Full-Bridge Center-Tapped Converters Using a Hybrid Fuzzy Sliding Mode Controller
Authors: Lee Young Jae , Bak Yeongsu , Lee Kyo-Beum
Published: June 2019

This paper presents a control method for phase-shift full-bridge center-tapped (PSFB-CT) converters using hybrid fuzzy sliding mode controllers (SMCs). Conventionally, the output voltage of a PSFB-CT converter is controlled by using a proportional-integral (PI) controller. However, the dynamic characteristic of the converter is undesirable, and the converter is not robust to disturbances. In order to overcome these disadvantages, the SMC based on PI control has been applied for the PSFB-CT converter. However, there is a chattering problem when the SMC gain is increased to improve the dynamic characteristic. In this paper, a control method for the PSFB-CT converter using fuzzy logic control is proposed. By varying the gain of the SMC through the fuzzy logic control, not only can the dynamic characteristic of the PSFB-CT converter be improved, but the chattering problem can also be relieved. The effectiveness of the proposed control method for the PSFB-CT converter was verified by the simulation and experimental results.
Validation of a SPICE Model for High Frequency Electroporation Systems
Authors: Butkus Paulius , Tolvaišienė Sonata , Kurčevskis Sebastjanas
Published: June 2019

In this paper, we present an analysis and a validation of a simulation program with integrated circuit emphasis (SPICE) model for a pulse forming circuit of a high frequency electroporation system, which can deliver square-wave sub-microsecond (100–900 ns) electric field pulses. The developed SPICE model is suggested for use in evaluation of transient processes that occur due to high frequency operations in prototype systems. A controlled crowbar circuit was implemented to support a variety of biological loads and to ensure a constant electric pulse rise and fall time during electroporation to be independent of the applied buffer bioimpedance. The SPICE model was validated via a comparison of the simulation and experimental results obtained from the already existing prototype system. The SPICE model results were in good agreement with the experimental results, and the model complexity was found to be sufficient for analysis of transient processes. As result, the proposed SPICE model can be useful for evaluation and compensation of transient processes in sub-microsecond pulsed power set-ups during the development of new prototypes.
Torque Coordination Control of Hybrid Electric Vehicles Based on Hybrid Dynamical System Theory
Authors: Fu Xiaoling , Zhang Qi , Wang Chao , Tang Jiyun
Published: June 2019

In order to reduce the vibration caused by mode switching of hybrid electric vehicles (HEVs) and achieve smooth mode switching, the hybrid input and output automation (HIOA) model of power control system of a parallel HEV is established based on the theory of hybrid dynamical system (HDS). Taking the switching from electric drive mode to hybrid drive mode for example, the torque coordination control is considered, and the performance is compared with the method without the torque coordination by using a rule-based control strategy. The simulation results in AVL Cruise show that, on the premise of ensuring the fuel economy and the emission, the mode switching process becomes smoother with smaller torque fluctuation and better driving comfort by considering the torque coordination.
EPSim-C: A Parallel Epoch-Based Cycle-Accurate Microarchitecture Simulator Using Cloud Computing
Authors: Kim Minseong , Kim Seon Wook , Han Youngsun
Published: June 2019

Recently, computing platforms have been being configured on a large scale to satisfy the diverse requirements of emerging applications like big data and graph processing, neural network, speech recognition and so on. In these computing platforms, each computing node consists of a multicore, an accelerator, and a complex memory hierarchy, which are connected to other nodes using a variety of high-performance networks. Up to now, researchers have been using cycle-accurate simulators to evaluate the performance of computer systems in detail. However, the execution of the simulators, which models modern computing architecture for multi-core, multi-node, datacenter, memory hierarchy, new memory, and new interconnection, is too slow and infeasible; since the architecture has become more complex today, the complexity of the simulator is rapidly increasing. Therefore, it is seriously challenging to employ them in the research and development of next-generation computer systems. To solve this problem, we previously presented EPSim (Epoch-based Simulator), which defines epochs that can be run independently by dividing the simulation run into several sections and executes them in parallel on a multicore platform, resulting in only the limited simulation speedup. In this paper, to overcome the computing resource limitations on multi-core platforms, we propose a novel EPSim-C (EPSim on Cloud) simulator that extends EPSim and achieves higher performance using a cloud computing platform. EPSim-C is designed to perform the epoch-based executions in a massively parallel fashion by using MapReduce on Hadoop-based systems. According to our experiments, we have achieved a maximum speed of 87.0× and an average speed of 46.1× using 256 cores. As far as we know, EPSim-C is the only existing way to accelerate the cycle-accurate simulator on cloud platforms; thus, our significant performance enhancement allows researchers to model and research current and future cutting-edge computing platforms using real workloads.
Deep Learning Neural Networks Trained with MODIS Satellite-Derived Predictors for Long-Term Global Solar Radiation Prediction
Authors: Ghimire Sujan , Deo Ravinesh C , Raj Nawin , Mi Jianchun
Published: June 2019

Solar energy predictive models designed to emulate the long-term (e.g., monthly) global solar radiation (GSR) trained with satellite-derived predictors can be employed as decision tenets in the exploration, installation and management of solar energy production systems in remote and inaccessible solar-powered sites. In spite of a plethora of models designed for GSR prediction, deep learning, representing a state-of-the-art intelligent tool, remains an attractive approach for renewable energy exploration, monitoring and forecasting. In this paper, algorithms based on deep belief networks and deep neural networks are designed to predict long-term GSR. Deep learning algorithms trained with publicly-accessible Moderate Resolution Imaging Spectroradiometer (MODIS) satellite data are tested in Australia’s solar cities to predict the monthly GSR: single hidden layer and ensemble models. The monthly-scale MODIS-derived predictors (2003–2018) are adopted, with 15 diverse feature selection approaches including a Gaussian Emulation Machine for sensitivity analysis used to select optimal MODIS-predictor variables to simulate GSR against ground-truth values. Several statistical score metrics are adopted to comprehensively verify surface GSR simulations to ascertain the practicality of deep belief and deep neural networks. In the testing phase, deep learning models generate significantly lower absolute percentage bias (≤3%) and high Kling–Gupta efficiency (≥97.5%) values compared to the single hidden layer and ensemble model. This study ascertains that the optimal MODIS input variables employed in GSR prediction for solar energy applications can be relatively different for diverse sites, advocating a need for feature selection prior to the modelling of GSR. The proposed deep learning approach can be adopted to identify solar energy potential proactively in locations where it is impossible to install an environmental monitoring data acquisition instrument. Hence, MODIS and other related satellite-derived predictors can be incorporated for solar energy prediction as a strategy for long-term renewable energy exploration.
Optimal Sizing of Battery Energy Storage for a Grid-Connected Microgrid Subjected to Wind Uncertainties
Authors: Abdulgalil Mohammed Atta , Khalid Muhammad , Alismail Fahad
Published: June 2019

In this paper, based on stochastic optimization methods, a technique for optimal sizing of battery energy storage systems (BESSs) under wind uncertainties is provided. Due to considerably greater penetration of renewable energy sources, BESSs are becoming vital elements in microgrids. Integrating renewable energy sources in a power system together with a BESS enhances the efficiency of the power system by enhancing its accessibility and decreasing its operating and maintenance costs. Furthermore, the microgrid-connected BESS should be optimally sized to provide the required energy and minimize total investment and operation expenses. A constrained optimization problem is solved using an optimization technique to optimize a storage system. This problem of optimization may be deterministic or probabilistic. In case of optimizing the size of a BESS connected to a system containing renewable energy sources, solving a probabilistic optimization problem is more effective because it is not possible to accurately determine the forecast of their output power. In this paper, using the stochastic programming technique to discover the optimum size of a BESS to connect to a grid-connected microgrid comprising wind power generation, a probabilistic optimization problem is solved. A comparison is then produced to demonstrate that solving the problem using stochastic programming provides better outcomes and to demonstrate that the reliability of the microgrid improves after it is connected to a storage system. The simulation findings demonstrate the efficacy of the optimum sizing methodology proposed.
Design of State Feedback Current Controller for Fast Synchronization of DFIG in Wind Power Generation Systems
Authors: Abo-Khalil Ahmed G. , Alghamdi Ali S. , Eltamaly Ali M. , Al-Saud M. S. , R. P. Praveen , Sayed Khairy , Bindu G. R. , Tlili Iskander
Published: June 2019

Doubly-fed induction generators (DFIGs) are widely used in wind energy conversion systems. The dynamic features of DFIGs make it important to focus on designing high-performance control schemes. However, the dynamic characteristics of such generators depend on nonlinear parameters, such as stator flux, stator current, and rotor current, which increase the overall system complexity. In addition, the DFIG Wind Energy Conversion Systems (WECSs) size is growing beyond 7 MW, which increases stress on both the mechanical drive train and the power circuits during connection to the grid. Such stress and dynamic features cannot be neglected. Therefore, robust controllers must be implemented which have the ability to support the dynamic frequencies of wind energy to ensure system stability in grid connection mode and during subsequent use. Conventional vector control configurations that use proportional-integral controllers have various drawbacks, such as parameter tuning difficulties, mediocre dynamic performance, and reduced robustness. In this study, we focused on improving DFIG synchronization to the grid by applying state feedback current controllers with a feedforward component to smooth the connection to the grid, as well as to improve the steady-state and transient characteristics of the controller. State feedback controllers are proposed to replace the proportional-integral controllers on both the rotor and grid sides. The proposed controller is designed using a multivariable system and feedforward control for input reference and incorporating disturbances into the control equations for fast synchronization and transient responses. To demonstrate the advantages of this controller, experimental studies are presented for both the transient and steady states.
Modified Electromechanical Modeling and Parameters Analysis of Magnetoplasmadynamic Thruster
Authors: Zhang Yu , Wu Jianjun , Ou Yang , Li Jian , Tan Sheng
Published: June 2019

To predict the thrust of magnetoplasmadynamic thrusters (MPDTs), a modified electromechanical model was proposed and a comparison with experimental results is presented in this paper. The motion of propellant in the thruster was divided into two portions: the axial motion which was accelerated by the interaction of current and induced self-field, and the swirling motion which was accelerated by the interaction of current and applied magnetic field. The electromechanical model was in good agreement with the experimental data, and the fitting degrees of the model were greater than 0.93. Furthermore, the influence of parameters on the performance of MPDT were investigated by utilizing the electromechanical model. The results indicate that the thrust performance of the thruster improved with the increase of discharge current, anode radius, applied magnetic field strength, and the decrease of mass flow rate. However, the large anode radius and low mass flow rate readily led to the failure of thruster function. Therefore, the model can not only predict the thrust performance of MPDTs, but also guide the design and operation optimization of the thruster.
Susceptibility of Small-Diameter Norway Spruce Understory Stumps to Heterobasidion Spore Infection
Authors: Gaitnieks Tālis , Zaļuma Astra , Kenigsvalde Kristīne , Kļaviņa Dārta , Brauners Indulis , Piri Tuula
Published: June 2019

Heterobasidion spp. cause economically important losses in conifer forests in the Northern Hemisphere, especially in Norway spruce stands. Freshly cut stumps are the main route for Heterobasidion spp. infection. Even small stumps of spruce seedlings are known to be susceptible to spore infection, however, very little is currently known about the susceptibility of small stumps of understory spruce to Heterobasidion spore infection. To determine the frequency of spore infections among stumps of understory trees, we analyzed 756 Norway spruce stumps in eight sample plots in eastern Latvia. Understory trees 35–68 years of age, with a stump diameter of 2–10 cm, were felled 33–48 weeks before sampling. In total, 514 (68%) of the spruce stumps were infected by Heterobasidion spores. The infection frequency among the plots varied from 56% to 86%. Both infection frequency and stump surface area occupied by Heterobasidion positively correlated with stump diameter, but neither correlated with the time span elapsed between felling and sampling. Colonization of trees by a competitor fungus, Phlebiopsis gigantea (Fr.) Jülich, was observed in 30 (4%) of investigated stumps, but did not have any effect on the frequency of Heterobasidion infections. Our data show that Norway spruce stumps can be highly susceptible to Heterobasidion spore infection. In order to control airborne Heterobasidion infections, stump treatment should be considered during the sporulation period of Heterobasidion spp.
Microstratigraphic Records as Tools for the Detection of Climatic Changes in Tana di Badalucco Cave (Liguria, NW Italy)
Authors: Sessa Eleonora , Rellini Ivano , Traverso Antonella , Molinari Irene , Montinari Giulio , Rossi Guido , Firpo Marco
Published: June 2019

Tana di Badalucco cave is located in Imperia (Liguria, Italy), not far from the French border. This site is scarcely known and it has never been studied accurately, even though different archaeological excavations have returned really important elements, both in the archaeological and the paleoenvironmental aspects. Its stratigraphy ranges from Middle Paleolithic to Metal Ages, thus it has registered important climate and environmental variations specific to the Upper Pleistocene and Holocene. From 2012, the Soprintendenza Archeologia della Liguria, the Museo di Archeologia Ligure, and DiSTAV (University of Genova) have been collaborating in order to finally study this promising and complex stratigraphy, trying to reconstruct the paleoenvironmental context of the region. In this work, we present what we were able to assess thanks to the use of micromorphology, the study of undisturbed thin soil sections. This technique has proven useful in recognizing the alternating of cold and warmer conditions during the Quaternary, as well as in identifying primitive signs of human and animal occupation.
Development and Process Evaluation of a Complex Intervention for Improving Nutrition among Hospitalised Patients: A Mixed Methods Study
Authors: Roberts Shelley , Grealish Laurie , Williams Lauren T. , Hopper Zane , Jenkins Julie , Spencer Alan , Marshall Andrea P.
Published: June 2019

Hospital-acquired malnutrition is a significant issue with complex aetiology, hence nutrition interventions must be multifaceted and context-specific. This paper describes the development, implementation and process evaluation of a complex intervention for improving nutrition among medical patients in an Australian hospital. An integrated knowledge translation (iKT) approach was used for intervention development, informed by previous research. Intervention strategies targeted patients (via a nutrition intake monitoring system); staff (discipline-specific training targeting identified barriers); and the organisation (foodservice system changes). A process evaluation was conducted parallel to implementation assessing reach, dose, fidelity and staff responses to the intervention using a mixed-methods design (quantitative and qualitative approaches). Staff-level interventions had high fidelity and broad reach (61% nurses, 93% foodservice staff and all medical staff received training). Patient and organisation interventions were implemented effectively, but due to staffing issues, only reached around 60% of patients. Staff found all intervention strategies acceptable with benefits to practice. This study found an iKT approach useful for designing a nutrition intervention that was context-specific, feasible and acceptable to staff. This was likely due to engagement of multiple disciplines, identifying and targeting specific areas in need of improvement, and giving staff frequent opportunities to contribute to intervention development/implementation.
Work Ability and Vitality in Coach Drivers: An RCT to Study the Effectiveness of a Self-Management Intervention during the Peak Season
Authors: van Schaaijk Art , Nieuwenhuijsen Karen , Frings-Dresen Monique
Published: June 2019

Background: This randomized controlled trial (RCT) evaluates the effectiveness of a self-management toolbox designed to maintain work ability and vitality in coach drivers over their peak season. Methods: The intervention group received a self-management intervention providing advice aimed at increasing work ability and vitality. These suggestions targeted three specific domains: work–recovery–rest balance, food and drink intake, and physical activity. At the beginning (March), middle (July), and end (October) of the coach sector peak season, work ability, vitality, work-related fatigue, psychosomatic health, sleep complaints, and perceived mental exertion of coach drivers were assessed through questionnaires. Results: A total of 96 drivers participated in the study. Access to the toolbox did not result in significant differences between groups. Work ability and vitality decreased significantly in both groups, falling from 7.8 ± 1.3 to 7.3 ± 1.6 and from 63 ± 16.7 to 55 ± 18.7, respectively. Work-related fatigue increased from 35 ± 31.9 to 52 ± 35.3. Psychosomatic health complaints, sleep complaints, and perceived mental exertion also increased significantly. Conclusions: The uptake of the intervention was too low to determine if this toolbox can maintain work ability and vitality in coach drivers when compared with a control group. Overall work ability and vitality decrease significantly as the peak season progresses, while work-related fatigue accumulates. Other interventions should be explored to ensure sustainable employability in this population.
Environmental Assessment of a Hybrid Solar-Biomass Energy Supplying System: A Case Study
Authors: Zhang Congguang , Sun Jiaming , Ma Jieying , Xu Fuqing , Qiu Ling
Published: June 2019

Local energy supply by renewable energy, such as solar energy and biomass, using distributed energy systems plays an important role in global energy structure. This study investigated the environmental performance of a hybrid solar-biomass energy supplying system by life-cycle assessment method. The results showed that in terms of environmental and energy impacts, the construction stage and the disassembly and recycling stage of the system contribute little to the whole life-cycle environmental impacts. According to the results of most of the selected impact categories, the solar subsystem contributed the most environmental emissions during construction stage, followed by the two anaerobic reactors; therefore, the excessive pursuit of high solar energy proportion can correspondingly lead to even more serious environmental problems. The integrated energy supplying system significantly reduces non-renewable energy consumption, climate change impacts, acidification as well as eutrophication effects due to the replacement of alternatives such as lignite coal, and from fertilizer production. The present hybrid solar-biomass energy supplying system not only produces clean thermal energy but also reduces the disposal of organic wastes and produces valuable agricultural products.