bluuebunny/crossref_metadata_2025 huggingface dataset:
Wind and Tide-Induced Hydrodynamics and Sedimentation of Two Tidal Inlets in Western Greece
Authors: Fourniotis Nikolaos Th. , Horsch Georgios M. , Leftheriotis Georgios A.
Published: May 2018

To quantify the detailed mechanisms that cause sedimentation at the tidal inlets in the Messolonghi-Aetoliko lagoonal system, the MIKE 21 FM (HD & ST) numerical simulation models were applied. The study focuses on the hydrodynamic circulation in the vicinity of the tidal inlets and the associated wind and tide-induced currents, as well as sediment transport, bed level evolution and total sediment load accumulation, with emphasis on the vicinity of two tidal inlets, where the problem is more acute. Based on the numerical predictions, which have been qualitatively corroborated via satellite images from Google Earth, it is shown that under the prevailing winds and tidal action, sandbars are formed in front or behind the tidal inlets depending on the wind direction, resulting in a gradual decrease of the mean water level at the mouths. Under the combined action of the tide and the wind the characteristic horizontal structure of the flow includes cyclonic and anti-cyclonic eddies that form at the near tip area of the jetties, which are associated with sediment transport mechanisms.
Effect of Sodium Carbonate Concentration in Calgon on Hydrometer Analysis Results
Authors: Kaur Arshdeep , Fanourakis George C.
Published: May 2018

Calgon (a combination of sodium hexametaphosphate and sodium carbonate) has proved to be the most effective dispersing agent in determining the grain size distribution of fine-grained soils by means of the hydrometer analysis. Previous research on the effect of the sodium hexametaphosphate content of dispersing agents on the clay contents showed that the addition of sodium carbonate to sodium hexametaphosphate increases its dispersing effectiveness. Hence, Calgon 35:7 was used /recommended by many researchers/methods and proved to be the most effective dispersing agent. Although previous work focusing on the effect of varying the concentration of sodium hexametaphosphate in Calgon has been reported, the effect of the concentration of sodium carbonate in Calgon has not been assessed and reported. For this reason, in this investigation a series of hydrometer test analyses were conducted using the 152H and ASTM 152H: E100 hydrometers with Calgon in ratios of 35:0, 35:20 and 35:30.  It was observed that with any increase in sodium carbonate content beyond 7 grams, the percentage clay content actually decreased tremendously in the case of hydrometer 152H. However, for the other hydrometer, Calgon (35:0) proved to be most effective combination. Thus, the increase in the sodium carbonate content in Calgon, beyond 7 g/ litre, is not recommended.
A Shack-Hartmann Sensor for Single-Shot Multi-Contrast Imaging with Hard X-rays
Authors: Dos Santos Rolo Tomy , Reich Stefan , Karpov Dmitry , Gasilov Sergey , Kunka Danays , Fohtung Edwin , Baumbach Tilo , Plech Anton
Published: May 2018

An array of compound refractive X-ray lenses (CRL) with 20 × 20 lenslets, a focal distance of 20cm and a visibility of 0.93 is presented. It can be used as a Shack-Hartmann sensor for hard X-rays (SHARX) for wavefront sensing and permits for true single-shot multi-contrast imaging the dynamics of materials with a spatial resolution in the micrometer range, sensitivity on nanosized structures and temporal resolution on the microsecond scale. The object’s absorption and its induced wavefront shift can be assessed simultaneously together with information from diffraction channels. In contrast to the established Hartmann sensors the SHARX has an increased flux efficiency through focusing of the beam rather than blocking parts of it. We investigated the spatiotemporal behavior of a cavitation bubble induced by laser pulses. Furthermore, we validated the SHARX by measuring refraction angles of a single diamond CRL, where we obtained an angular resolution better than 4 μ rad.
Captioning Transformer with Stacked Attention Modules
Authors: Zhu Xinxin , Li Lixiang , Liu Jing , Peng Haipeng , Niu Xinxin
Published: May 2018

Image captioning is a challenging task. Meanwhile, it is important for the machine to understand the meaning of an image better. In recent years, the image captioning usually use the long-short-term-memory (LSTM) as the decoder to generate the sentence, and these models show excellent performance. Although the LSTM can memorize dependencies, the LSTM structure has complicated and inherently sequential across time problems. To address these issues, recent works have shown benefits of the Transformer for machine translation. Inspired by their success, we develop a Captioning Transformer (CT) model with stacked attention modules. We attempt to introduce the Transformer to the image captioning task. The CT model contains only attention modules without the dependencies of the time. It not only can memorize dependencies between the sequence but also can be trained in parallel. Moreover, we propose the multi-level supervision to make the Transformer achieve better performance. Extensive experiments are carried out on the challenging MSCOCO dataset and the proposed Captioning Transformer achieves competitive performance compared with some state-of-the-art methods.
A Survey on the Mathematical Foundations of Axiomatic Entropy: Representability and Orderings
Authors: Campión María-Jesús , Gómez-Polo Cristina , Induráin Esteban , Raventós-Pujol Armajac
Published: May 2018

Different abstract versions of entropy, encountered in science, are interpreted in the light of numerical representations of several ordered structures, as total-preorders, interval-orders and semiorders. Intransitivities, other aspects of entropy as competitive systems, additivity, etc., are also viewed in terms of representability of algebraic structures endowed with some compatible ordering. A particular attention is paid to the problem of the construction of an entropy function or their mathematical equivalents. Multidisciplinary comparisons to other similar frameworks are also discussed, pointing out the mathematical foundations.
Prevalence of Developmental Dyslexia in Spanish University Students
Authors: López-Escribano Carmen , Suro Sánchez Judith , Leal Carretero Fernando
Published: May 2018

A recent concern in the field of dyslexia studies is the lack of awareness and attention to university students suffering from this condition. If this problem is serious in countries where the relative opacity of the writing system allows for an early detection and, therefore, effective interventions, it is most critical in countries where transparent spelling makes such detection difficult, except in the most severe cases. In Spain, the diagnosis of dyslexia is rare among university-level adults. The present study pursues three aims: (a) to put forward a screening instrument for the detection of university students at risk of dyslexia, (b) to determine the ratio of university students that could be at risk of dyslexia by means of two different procedures, and (c) to create awareness for a disorder that causes hitherto unrecognized difficulties for an important subgroup of the college population. Six hundred and eighty-six university students in four different fields of study within the general area of Social Sciences from a public University in Madrid completed a Spanish-adapted version of a protocol including stress assignment, spelling words and nonwords, and timed phonological working memory of reading and writing task. Results showed that between 1.6% and 6.4% of this population could be at risk of suffering dyslexia. Such risk is not evenly distributed across the four fields of study. As for gender, the first criterion used yields 1.8 males at risk for every female, but the second criterion has as many males as females at risk. Women were significantly better than men in word spelling. Spelling was best predicted by the timed phonological working memory task of reading and writing.
Analysis of Daylight Control in a Chateau Interior
Authors: Mohelníková Jitka , Míček Denis , Floreková Skarleta , Selucká Alena , Dvořák Martin
Published: May 2018

Assessment of daylighting in the residential hall of a historical chateau is presented. The evaluation is based on both the daylight measurement and simulations. Illuminance levels in the interior were controlled in accordance with requirements for light exposition of light sensitive materials. Valuable paintings and claddings as well as wallpapers and furniture upholstery in the hall are extremely light sensitive and they need to be protected from light damage. The daylight measurements and simulations give an overview of daylight conditions in the annual profile for clear sky conditions and for different levels of window shadings.
Nuclear Export Inhibition for Pancreatic Cancer Therapy
Authors: Muqbil Irfana , Azmi Asfar S. , Mohammad Ramzi M.
Published: May 2018

Pancreatic cancer is a deadly disease that is resistant to most available therapeutics. Pancreatic cancer to date has no effective drugs that could enhance the survival of patients once their disease has metastasized. There is a need for the identification of novel actionable drug targets in this unusually recalcitrant cancer. Nuclear protein transport is an important mechanism that regulates the function of several tumor suppressor proteins (TSPs) in a compartmentalization-dependent manner. High expression of the nuclear exporter chromosome maintenance region 1 (CRM1) or exportin 1 (XPO1), a common feature of several cancers including pancreatic cancer, results in excessive export of critical TSPs to the incorrect cellular compartment, leading to their functional inactivation. Small molecule inhibitors of XPO1 can block this export, retaining very important and functional TSPs in the nucleus and leading to the effective killing of the cancer cells. This review highlights the current knowledge on the role of XPO1 in pancreatic cancer and how this serves as a unique and clinically viable target in this devastating and by far incurable cancer.
Patient-Derived iPSCs and iNs—Shedding New Light on the Cellular Etiology of Neurodegenerative Diseases
Authors: Tang Bor Luen
Published: May 2018

Induced pluripotent stem cells (iPSCs) and induced neuronal (iN) cells are very much touted in terms of their potential promises in therapeutics. However, from a more fundamental perspective, iPSCs and iNs are invaluable tools for the postnatal generation of specific diseased cell types from patients, which may offer insights into disease etiology that are otherwise unobtainable with available animal or human proxies. There are two good recent examples of such important insights with diseased neurons derived via either the iPSC or iN approaches. In one, induced motor neurons (iMNs) derived from iPSCs of Amyotrophic lateral sclerosis/Frontotemporal dementia (ALS/FTD) patients with a C9orf72 repeat expansion revealed a haploinsufficiency of protein function resulting from the intronic expansion and deficiencies in motor neuron vesicular trafficking and lysosomal biogenesis that were not previously obvious in knockout mouse models. In another, striatal medium spinal neurons (MSNs) derived directly from fibroblasts of Huntington’s disease (HD) patients recapitulated age-associated disease signatures of mutant Huntingtin (mHTT) aggregation and neurodegeneration that were not prominent in neurons differentiated indirectly via iPSCs from HD patients. These results attest to the tremendous potential for pathologically accurate and mechanistically revealing disease modelling with advances in the derivation of iPSCs and iNs.
Modeling the Adaptive Immunity and Both Modes of Transmission in HIV Infection
Authors: Hattaf Khalid , Yousfi Noura
Published: May 2018

Human immunodeficiency virus (HIV) is a retrovirus that causes HIV infection and over time acquired immunodeficiency syndrome (AIDS). It can be spread and transmitted through two fundamental modes, one by virus-to-cell infection, and the other by direct cell-to-cell transmission. In this paper, we propose a new mathematical model that incorporates both modes of transmission and takes into account the role of the adaptive immune response in HIV infection. We first show that the proposed model is mathematically and biologically well posed. Moreover, we prove that the dynamical behavior of the model is fully determined by five threshold parameters. Furthermore, numerical simulations are presented to confirm our theoretical results.
On the Phylogenetic Position of the Weevil Tribe Acentrusini Alonso-Zarazaga, 2005 (Coleoptera: Curculionidae: Curculioninae)
Authors: Košťál Michael , Vďačný Peter
Published: May 2018

Based on intrinsic morphological and extrinsic bionomic characters, the systematic position of the weevil tribe Acentrusini Alonso-Zarazaga, 2005 (Coleoptera: Curculionidae: Curculioninae) was determined. Maximum parsimony and Bayesian inference as well as nonmetric multi-dimensional scaling were used to analyze 34 morphological characters of adults, complemented by four host plant characters associated with particular weevil tribes. Sixteen species belonging to two subfamilies (Brachycerinae, Curculionidae) and seven tribes (Acentrusini, Anthonomini, Ellescini, Erirhinini, Smicronychini, Storeini, Styphlini) of the family Curculionidae and one outgroup species (Attelabidae) were studied. Phylogenetic and multi-dimensional analyses revealed the tribe Smicronychini as most closely related to Acentrusini. Of the tribes of Curculioninae studied, Styphlini, Anthonomini and Ellescini showed a certain degree of phylogenetic relation to Acentrusini, whereas Storeini were found to be least related.
Plant Trait Dataset for Tree-Like Growth Forms Species of the Subtropical Atlantic Rain Forest in Brazil
Authors: Rodrigues Arthur Vinicius , Bones Fábio Leal Viana , Schneiders Alisson , Oliveira Laio Zimermann , Vibrans Alexander Christian , Gasper André Luís de
Published: May 2018

Plant functional traits have been incorporated in studies of vegetation ecology to better understand the mechanisms of ecological processes. For this reason, a global effort has been made to collect functional traits data for as many species as possible. In light of this, we identified the most common species of an area of 15,335 km2 inserted in the subtropical Atlantic Rain Forest in Southern Brazil. Then, we compiled functional trait information mostly from field samples, but also from herbarium and literature. The dataset presents traits of leaf, branch, maximum potential height, seed mass, and dispersion syndrome of 117 species, including trees, tree ferns, and palms. We also share images of anatomical features of branches used to measure wood traits. Data tables present mean trait values at individual and species level. Images of wood and stomatal features may be useful to assess other anatomical traits that were not covered in the data tables for the anatomical determination of species and/or for educational purposes.
Numerical Study on Entropy Generation in Thermal Convection with Differentially Discrete Heat Boundary Conditions
Authors: Wang Zhengdao , Wei Yikun , Qian Yuehong
Published: May 2018

Entropy generation in thermal convection with differentially discrete heat boundary conditions at various Rayleigh numbers (Ra) are numerically investigated using the lattice Boltzmann method. We mainly focused on the effects of Ra and discrete heat boundary conditions on entropy generation in thermal convection according to the minimal entropy generation principle. The results showed that the presence of the discrete heat source at the bottom boundary promotes the transition to a substantial convection, and the viscous entropy generation rate (Su) generally increases in magnitude at the central region of the channel with increasing Ra. Total entropy generation rate (S) and thermal entropy generation rate (Sθ) are larger in magnitude in the region with the largest temperature gradient in the channel. Our results also indicated that the thermal entropy generation, viscous entropy generation, and total entropy generation increase exponentially with the increase of Rayleigh number. It is noted that lower percentage of single heat source area in the bottom boundary increases the intensities of viscous entropy generation, thermal entropy generation and total entropy generation. Comparing with the classical homogeneous thermal convection, the thermal entropy generation, viscous entropy generation, and total entropy generation are improved by the presence of discrete heat sources at the bottom boundary.
Capacity Optimization of a Centralized Charging Station in Joint Operation with a Wind Farm
Authors: Jiang Zhe , Han Xueshan , Li Zhimin , Wang Mingqiang , Liu Guodong , Wang Mengxia , Li Wenbo , Ollis Thomas B.
Published: May 2018

In the context of large-scale wind power integration and rapid development of electric vehicles (EVs), a joint operation pattern was proposed to use a centralized charging station (CCS) to address high uncertainties incurred by wind power integration. This would directly remove the significant indeterminacy of wind power. Because the CCS is adjacent to a wind power gathering station, it could work jointly with wind farms to operate in power system as an independent enterprise. By combining the actual operational characteristics of the wind farm and the CCS, a multidimensional operating index evaluation system was created for the joint system. Based on the wind farm’s known capacity, a multi-target capacity planning model was established for CCS to maximize the probability of realizing diverse indices of the system based on dependent-chance goal programming. In this model, planning and dispatching are combined to improve the feasibility of results in the operational stage. This approach takes the effects of randomness into account for wind power and battery swapping. The model was solved through combining Monte Carlo simulation and a genetic algorithm (GA) based on segmented encoding. As shown in the simulation results, the proposed model could comprehensively include factors such as initial investment, wind power price, battery life, etc., to optimize CCS capacity and to ultimately improve the operating indices of the joint system.
Real-Time Demand Side Management Algorithm Using Stochastic Optimization
Authors: Amoasi Acquah Moses , Kodaira Daisuke , Han Sekyung
Published: May 2018

A demand side management technique is deployed along with battery energy-storage systems (BESS) to lower the electricity cost by mitigating the peak load of a building. Most of the existing methods rely on manual operation of the BESS, or even an elaborate building energy-management system resorting to a deterministic method that is susceptible to unforeseen growth in demand. In this study, we propose a real-time optimal operating strategy for BESS based on density demand forecast and stochastic optimization. This method takes into consideration uncertainties in demand when accounting for an optimal BESS schedule, making it robust compared to the deterministic case. The proposed method is verified and tested against existing algorithms. Data obtained from a real site in South Korea is used for verification and testing. The results show that the proposed method is effective, even for the cases where the forecasted demand deviates from the observed demand.
Energy Efficiency and Controllability of Fluid Power Systems
Authors: Vacca Andrea
Published: May 2018

Fluid power refers to the discipline that involves the use of fluids to perform mechanical actuations, it is a well-established and independent discipline that has a defined research area and scholarly activities since at least seven decades.[...]
Fundamental Material Properties of the 2LiBH4-MgH2 Reactive Hydride Composite for Hydrogen Storage: (II) Kinetic Properties
Authors: Jepsen Julian , Milanese Chiara , Puszkiel Julián , Girella Alessandro , Schiavo Benedetto , Lozano Gustavo A. , Capurso Giovanni , Bellosta von Colbe José M. , Marini Amedeo , Kabelac Stephan , Dornheim Martin , Klassen Thomas
Published: May 2018

Reaction kinetic behaviour and cycling stability of the 2LiBH4–MgH2 reactive hydride composite (Li-RHC) are experimentally determined and analysed as a basis for the design and development of hydrogen storage tanks. In addition to the determination and discussion about the properties; different measurement methods are applied and compared. The activation energies for both hydrogenation and dehydrogenation are determined by the Kissinger method and via the fitting of solid-state reaction kinetic models to isothermal volumetric measurements. Furthermore, the hydrogen absorption–desorption cycling stability is assessed by titration measurements. Finally, the kinetic behaviour and the reversible hydrogen storage capacity of the Li-RHC are discussed.
Modeling Hydrogen Refueling Infrastructure to Support Passenger Vehicles †
Authors: Muratori Matteo , Bush Brian , Hunter Chad , Melaina Marc W.
Published: May 2018

The year 2014 marked hydrogen fuel cell electric vehicles (FCEVs) first becoming commercially available in California, where significant investments are being made to promote the adoption of alternative transportation fuels. A refueling infrastructure network that guarantees adequate coverage and expands in line with vehicle sales is required for FCEVs to be successfully adopted by private customers. In this paper, we provide an overview of modelling methodologies used to project hydrogen refueling infrastructure requirements to support FCEV adoption, and we describe, in detail, the National Renewable Energy Laboratory’s scenario evaluation and regionalization analysis (SERA) model. As an example, we use SERA to explore two alternative scenarios of FCEV adoption: one in which FCEV deployment is limited to California and several major cities in the United States; and one in which FCEVs reach widespread adoption, becoming a major option as passenger vehicles across the entire country. Such scenarios can provide guidance and insights for efforts required to deploy the infrastructure supporting transition toward different levels of hydrogen use as a transportation fuel for passenger vehicles in the United States.
Experimental Study and Modeling of Ground-Source Heat Pumps with Combi-Storage in Buildings
Authors: El-Baz Wessam , Tzscheutschler Peter , Wagner Ulrich
Published: May 2018

There is a continuous growth of heat pump installations in residential buildings in Germany. The heat pumps are not only used for space heating and domestic hot water consumption but also to offer flexibility to the grid. The high coefficient of performance and the low cost of heat storages made the heat pumps one of the optimal candidates for the power to heat applications. Thus, several questions are raised about the optimal integration and control of heat pump system with buffer storages to maximize its operation efficiency and minimize the operation costs. In this paper, an experimental investigation is performed to study the performance of a ground source heat pump (GSHP) with a combi-storage under several configurations and control factors. The experiments were performed on an innovative modular testbed that is capable of emulating a ground source to provide the heat pump with different temperature levels at different times of the day. Moreover, it can emulate the different building loads such as the space heating load and the domestic hot water consumption in real-time. The data gathered from the testbed and different experimental studies were used to develop a simulation model based on Modelica that can accurately simulate the dynamics of a GSHP in a building. The model was validated based on different metrics. Energetically, the difference between the developed model and the measured values was only 3% and 4% for the heat generation and electricity consumption, respectively.
Multi-Criteria Decision Analysis for Benchmarking Human-Free Lifting Solutions in the Offshore Wind Energy Environment
Authors: Richmond Mark , Balaam Toby , Causon Paul , Cevasco Debora , Leimeister Mareike , Kolios Athanasios , Brennan Feargal
Published: May 2018

With single components weighing up to hundreds of tonnes and lifted to heights of approximately 100 m, offshore wind turbines can pose risks to personnel, assets, and the environment during installation and maintenance interventions. Guidelines and standards for health and safety in lifting operations exist; however, having people directly beneath the load is still common practice in offshore wind turbine installations. Concepts for human-free offshore lifting operations in the categories of guidance and control, connections, and assembly are studied in this work. This paper documents the process of applying Multi-Criteria Decision Analysis (MCDA), using experts’ opinions for the importance of defined criteria obtained by conducting an industry survey, to benchmark the suitability of the concepts at two stages. Stage one streamlined possible options and stage two ranked the remaining suite of options after further development. The survey results showed that criteria such as ‘reduction of risk’, ‘handling improvement’ and ‘reliability of operation’ were most important. The most viable options, weighted by industry opinion, to remove personnel from areas of high risk are: Boom Lock and tag lines, a camera system with mechanical guidance, and automated bolt installation/fastening for seafastening. The decision analysis framework developed can be applied to similar problems to inform choices subject to multiple criteria.
Simulation for the Effects of Well Pressure and Initial Temperature on Methane Hydrate Dissociation
Authors: Yu Minghao , Li Weizhong , Dong Bo , Chen Cong , Wang Xin
Published: May 2018

Methane hydrate dissociation is a process of heat and mass transfer, and pressure and temperature are the most important parameters. The influence of pressure and temperature on the hydrate dissociate relationship between the two parameters is the determinant for gas hydrate dissociation; meanwhile, the gradients of these parameters are the sources of flow and gas production. In this study, a 1D simulator was developed for investigating the effects of well pressures (3 MPa, 5 MPa, and 8 MPa) and initial temperatures (274 K, 279 K, and 284 K) in the process of methane hydrate dissociation by depressurization. The simulation results showed that the well pressure and initial temperature have significant effects on pressure distribution, temperature distribution, and gas production. A lower well pressure and higher initial temperature can promote methane hydrate dissociation. The combined effect of hydrate dissociation and fluid flow can cause more substantial changes in pressure distribution, temperature distribution, and gas production, especially in the initial stage of the methane hydrate dissociation process. However, the changes of the parameters tend to disappear as mining time goes on. There is a difference in the influences of exploitation well pressure and initial temperature on the stability time of gas production.
Residential Electricity Consumption Level Impact Factor Analysis Based on Wrapper Feature Selection and Multinomial Logistic Regression
Authors: Wang Fei , Yu Yili , Wang Xinkang , Ren Hui , Shafie-Khah Miadreza , Catalão João P. S.
Published: May 2018

This paper aims to identity the significant impact factors (IFs) of the residential electricity consumption level (RECL) and to better understand the influence mechanism of IFs on RECL. The analysis of influence mechanism is commonly through regression model where feature selection must first be performed to pick out non-redundant IFs that is highly correlated with RECL. In contrast to the existing studies, this study recognizes the problem that majority feature selection methods (e.g., step regression) are limited to the identification of linear relationships and proposes a novel wrapper feature selection (WFS) method to address this issue. The WFS is based on genetic algorithm (GA) and multinomial logistic regression (MLR). GA is a searching algorithm used to generate different feature subsets (FSs) that consist of several IFs. MLR is a modeling algorithm used to score these FSs. Further, maximal information coefficient (MIC) is utilized to verify the validity of WFS for selecting IFs. Finally, MLR based explanatory model is established to excavate the relationship between selected IFs and RECL. The results of Ireland dataset based case study show that WFS can identify the significant and non-redundant IFs that are linearly or nonlinearly related to RECL. The details about how selected IFs affect RECL are also provided via the explanatory model. Such research can provide useful guidance for a wide range of stakeholders including local governments, electric power companies, and individual households.
Energy Demand Comparison between Hollow Fiber Membrane Based Dehumidification and Evaporative Cooling Dehumidification Using TRNSYS
Authors: Jang Jeachul , Kang Eun-Chul , Lee Hyung Keun , Jeong Siyoung , Park Seong-Ryong
Published: May 2018

This communication presents the performance evaluation and comparative study between two different techniques: a membrane-based dehumidification system (MDS) and evaporative cooling dehumidification (ECD) for a typical climate of South Korea. Although there are different ways to dehumidify the air in living and work spaces, the membrane-based dehumidification system (MDS) is the most effective way as it neither causes a change in the temperature nor harms the environment. Moreover, it consumes significantly less energy when compared to other methods. There are also limitations concerning products that are sensitive to temperature such as food and pharmaceutical products; the method of evaporative cooling dehumidification is not suitable for such applications. The present work demonstrated the excellent energy-saving performance of the membrane-based dehumidification system against evaporative cooling dehumidification by comparing the performance of these two systems during the rainy season using a transient system simulation. The results showed that the MDS helped to reduce the dehumidification load by more than 47.6% when compared to the ECD system, which is a significant achievement in this regard.
IGBT Dynamic Loss Reduction through Device Level Soft Switching
Authors: Ma Lan , Xu Hongbing , Huang Alex Q. , Zou Jianxiao , Li Kai
Published: May 2018

Due to its low conduction loss, hence high current ratings, as well as low cost, Silicon Insulated Gate Bipolar Transistor (Si IGBT) is widely used in high power applications. However, its switching frequency is generally low because of relatively large switching losses. Silicon carbide Metal-Oxide-Semiconductor Field-Effect Transistor (SiC MOSFET) is much more superior due to their fast switching speed, which is determined by the internal parasitic capacitance instead of the stored charges, like the IGBT. By the combination of SiC MOSFET and Si IGBT, this paper presents a novel series hybrid switching method to achieve IGBT’s dynamic switching loss reduction by switching under Zero Voltage Hard Current (ZVHC) turn-on and Zero Current Hard Voltage (ZCHV) turn-off conditions. Both simulation and experimental results of IGBT are carried out, which shows that the soft switching of IGBT has been achieved both in turn-on and turn-off period. Thus 90% turn-on loss and 57% turn-off loss are reduced. Two different IGBTs’ test results are also provided to study the modulation parameter’s effect on the turn-off switching loss. Furthermore, with the consideration of voltage and current transient states, a new soft switching classification is proposed. At last, another improved modulation and Highly Efficient and Reliable Inverter Concept (HERIC) inverter are given to validate the effectiveness of the device level hybrid soft switching method application.
Fractional Order Chaos Synchronization for Real-Time Intelligent Diagnosis of Islanding in Solar Power Grid Systems
Authors: Fu Cheng-Biao , Tian An-Hong , Li Yu-Chung , Yau Her-Terng
Published: May 2018

Many different methods have been proposed for determining islanding and most of them have drawbacks. The main issue is the difficulty of detecting islanding when the current and voltage values are of the same phase or the frequency remains within the normal range of the grid when islanding occurs. In this study, a non-autonomous Chua’s circuit was used to preprocess the grid signal after which a method based on the fractional Lorenz chaotic system and extension theory was used to analyze the preprocessed voltage signal. The capability of a chaotic system to amplify an extremely small signal was effectively utilized for the diagnosis of grid islanding. Simulation results showed that the diagnostic accuracy of the proposed method could be 100% and no other diagnostic method has offered such accuracy. Furthermore, the method proposed in this study is simple, easy to implement, and could be used as a portable system for the real-time monitoring and diagnosis of islanding in a conventional home grid system.
Overview of Powertrain Electrification and Future Scenarios for Non-Road Mobile Machinery
Authors: Lajunen Antti , Sainio Panu , Laurila Lasse , Pippuri-Mäkeläinen Jenni , Tammi Kari
Published: May 2018

Powertrain electrification continues to be a growing trend in vehicular applications. Electric powertrains have numerous advantages over traditional mechanical and hydraulic powertrains but there are still important challenges to overcome for long-term commercial success. This research presents a technological assessment of present and future developments of powertrain electrification in non-road mobile machinery (NRMM). The challenges and opportunities of NRMM electrification are described in detail. The trends and drivers related to technological development such as regulations, policies and market development are analyzed, and technology enablers are highlighted. Future scenarios are formulated based on the prevailing trends and drivers, development of key components, scientific literature and status of the non-road mobile machinery industry. Some recommendations are also given in relation to the development of hybrid and electric powertrains for NRMM. The key findings of this research indicate that the electrification of NRMM is slowly started and the progress is demonstrated by hybridization of some specific, successful mobile machines. In short-term, high component and technology development costs remain the main barrier for higher adoption of electric and hybrid powertrains. In the long-term scenario, many NRMM can operate autonomously and powertrain electrification has become mainstream technology.
Expedient Prediction of the Fuel Properties of Carbonized Woody Biomass Based on Hue Angle
Authors: Saito Yuta , Sakuragi Kiyoshi , Shoji Tetsuya , Otaka Maromu
Published: May 2018

Woody biomass co-firing-based power generation can reduce CO2 emissions from pulverized coal boilers. Carbonization of woody biomass increases its calorific value and grindability, thereby improving the co-firing ratio. Carbonized biomass fuel properties depend on moisture, size and shape of feedstock, and carbonization conditions. To produce carbonized biomass with stable fuel properties, the carbonization conditions should be set according to the desired fuel properties. Therefore, we examined color changes accompanying woody biomass carbonization and proposed using them for rapid evaluation of fuel properties. Three types of woody biomasses were carbonized at a test facility with a capacity of 4 tons/day, and the fuel properties of the obtained materials were correlated with their color defined by the L*a*b* model. When fixed carbon, an important fuel property for carbonization, was 25 wt % or less, we observed a strong negative correlation, regardless of the tree species, between the hue angle, hab, and fixed carbon. The hab and fixed carbon were correlated even when the fixed carbon exceeded 25 wt %; however, this correlation was specific to the tree species. These results indicate that carbonized biomass fuel properties such as fixed carbon can be estimated rapidly and easily by measuring hab.
Perceptions on the Importance of Forest Sector Innovations: Biofuels, Biomaterials, or Niche Products?
Authors: Stern T. , Ranacher L. , Mair C. , Berghäll S. , Lähtinen K. , Forsblom M. , Toppinen A.
Published: May 2018

New innovations are called for to renew the European forest sector into bioeconomy. However, little research exists on how the industry innovativeness is publicly perceived. Using data collected with an online questionnaire in four European countries, we investigate perceptions related to forest sector innovations on 13 current and new bioeconomy-related products and services. Altogether, 218 valid responses were received in 2015, and the data were analysed using descriptive statistics, performance-importance analysis, and Gartner’s innovation hype cycle. Based on our results, the respondents were in the strongest agreement that the forest sector has since the year 2000 has produced innovations related to wood building systems, construction materials, and wood composites. In the next 15 years, they foresaw a decline in innovations related to biofuels and paper products. The European forest sector also has future potential in wood construction, which is likely related to international policy targets related to carbon mitigation and capture. The observed variation in perceptions among the respondents on forest sector innovativeness calls for strengthening industry R&D, as well as by improving societal awareness of ongoing innovation projects by developing better communication.
Submesoscale Turbulence over a Topographic Slope
Authors: Lazar Ayah , Zhang Qiong , Thompson Andrew F.
Published: May 2018

Regions of the ocean near continental slopes are linked to significant vertical velocities caused by advection over a sloping bottom, frictional processes and diffusion. Oceanic motions at submesoscales are also characterized by enhanced vertical velocities, as compared to mesoscale motions, due to greater contributions from ageostrophic flows. These enhanced vertical velocities can make an important contribution to turbulent fluxes. Sloping topography may also induce large-scale potential vorticity gradients by modifying the slope of interior isopycnal surfaces. Potential vorticity gradients, in turn, may feed back on mesoscale stirring and the generation of submesoscale features. In this study, we explore the impact of sloping topography on the characteristics of submesoscale motions. We conduct high-resolution (1 km × 1 km) simulations of a wind-driven frontal current over an idealized continental shelf and slope. We explore changes in the magnitude, skewness and spectra of surface vorticity and vertical velocity across different configurations of the topographic slope and wind-forcing orientations. All of these properties are strongly modulated by the background topography. Furthermore, submesoscale characteristics exhibit spatial variability across the continental shelf and slope. We find that changes in the statistical properties of submesoscale motions are linked to mesoscale stirring responding to differences in the interior potential vorticity distributions, which are set by frictional processes at the ocean surface and over the sloping bottom. Improved parameterizations of submesoscale motions over topography may be needed to simulate the spatial variability of these features in coarser-resolution models, and are likely to be important to represent vertical nutrient fluxes in coastal waters.
Other Ways of Knowing: The Intersection of Education when Researching Family Roots
Authors: Hart Diana
Published: May 2018

The intersection of education and genealogy is of interest to academia. Although learning is an important aspect of the genealogist’s need to understand the connection with family relationships, there is a paucity of research about the intersection between education and genealogy. This study sought to answer the research question, “How do genealogists use education to better understand family connections?” A narrative inquiry method was used to interview 10 members of the Oberlin African-American Genealogy and History Group, in Oberlin, Ohio (OAAGHG). Participants were recruited through convenience sampling and purposive sampling, after an announcement about the study was presented at the January meeting of the genealogy society. Members who were interested in participating contacted the researcher through e-mails, text messages, and by telephone. Interviews were transcribed, and transcripts were sent to each member to verify the accuracy of each transcript. Nvivo11 was used to assist with analysis of the data. The results of the study presented three ways that education intersected with genealogy: self-directed learning, collaborative learning, and life-long learning. The conclusion of this study is that genealogists are life-long learners and expand their education as necessary to better understand family connections.
Mass Balance of Cenozoic Andes-Amazon Source to Sink System—Marañón Basin, Peru
Authors: Calvès Gérôme , Calderón Ysabel , Hurtado Enriquez Christian , Brusset Stéphane , Santini William , Baby Patrice
Published: May 2018

We investigate the mass balance of the Cenozoic Andes-Amazon source to sink system using rock uplift proxies and solid sedimentation of the Marañón Basin in Peru. The evolution of sedimentation rates is calibrated with regional structural restored cross-section. The quantification of eroded sediments from reliefs to sedimentary basin is achieved with ×10 Myr resolution and compared to present day proxies from the HYBAM (HYdrologie et Biogéochimie du Bassin Amazonien) Critical Zone Observatory. Erosion of the early Andean landforms started during the Upper Mesozoic period, but sediment rates significantly increase during the Neogene. This is in agreement with the calibrated increase of rock uplift in the Andean orogenic belt.
The Association between Quality Improvement Initiatives in Dementia Care and Supportive Psychosocial Work Environments in Nursing Homes
Authors: Nakanishi Miharu , Tei-Tominaga Maki
Published: May 2018

Background: Quality improvement initiatives can help nursing homes strengthen psychosocial work environments. The aim of the present study was to examine the association between supportive psychosocial work environment, and professional and organizational characteristics regarding quality improvement initiatives in dementia care. Methods: A paper questionnaire survey was administered to a convenience sample of 365 professional caregivers in 12 special nursing homes in Japan. Psychosocial work environment was assessed using the Social Capital and Ethical Climate at the Workplace Scale to calculate a score of social capital in the workplace, ethical leadership, and exclusive workplace climate. Variables for quality improvement initiatives included type of home (unit-type or traditional), presence of additional benefit for dementia care, and professionalism in dementia care among caregivers evaluated using the Japanese version of the Sense of Competence in Dementia Care Staff Scale. Results: Elevated professionalism and unit-type home were significantly associated with high social capital, strong ethical leadership, and low exclusive workplace climate. The presence of dementia care benefit was not associated with any subscale of psychosocial work environment. Conclusions: Quality improvement initiatives to foster supportive psychosocial work environment should enhance professionalism in dementia care with unit-based team building of professional caregivers in special nursing homes.
Systematic Literature Review of Attempted Suicide and Offspring
Authors: Lunde Ingeborg , Myhre Reigstad Marte , Frisch Moe Kristin , Grimholt Tine K.
Published: May 2018

Background: Exposure to parental suicide attempt is associated with higher risks of adverse outcomes like lower educational performance, drug abuse and delinquent behavior. When a patient is hospitalized after a suicide attempt, this presents a unique opportunity to identify whether the patient has children, and thereby provide adequate follow-up for both the parent/patient and their children. The objective of this paper was to review the existing literature on follow-up measures for children subjected to parental suicide attempt. Methods: In line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement, we conducted a systematic literature search. Results: The search resulted in a total of 1275 article titles, of which all abstracts were screened. Out of these, 72 full text papers were read, and a final four articles were included. Three of the included papers described parts of the same study from an emergency department in The Hague, where a protocol was implemented for monitoring and referring children of parents attempting suicide. The fourth article described the association between maternal attempted suicide and risk of abuse or neglect of their children. Conclusions: The lack of research in this particular area is striking. The circumstances surrounding a parent’s suicide attempt call for appropriate familial care.
Preanalytical Biases in the Measurement of Human Blood Sphingolipids
Authors: Brunkhorst Robert , Pfeilschifter Waltraud , Patyna Sammy , Büttner Stefan , Eckes Timon , Trautmann Sandra , Thomas Dominique , Pfeilschifter Josef , Koch Alexander
Published: May 2018

Dysregulation of blood sphingolipids is an emerging topic in clinical science. The objective of this study was to determine preanalytical biases that typically occur in clinical and translational studies and that influence measured blood sphingolipid levels. Therefore, we collected blood samples from four healthy male volunteers to investigate the effect of storage conditions (time, temperature, long-term storage, freeze–thaw cycles), blood drawing (venous or arterial sampling, prolonged venous compression), and sample preparation (centrifugation, freezing) on sphingolipid levels measured by LC-MS/MS. Our data show that sphingosine 1-phosphate (S1P) and sphinganine 1-phosphate (SA1P) were upregulated in whole blood samples in a time- and temperature-dependent manner. Increased centrifugation at higher speeds led to lower amounts of S1P and SA1P. All other preanalytical biases did not significantly alter the amounts of S1P and SA1P. Further, in almost all settings, we did not detect differences in (dihydro)ceramide levels. In summary, besides time-, temperature-, and centrifugation-dependent changes in S1P and SA1P levels, sphingolipids in blood remained stable under practically relevant preanalytical conditions.