Miracle-dz/UniFAR-FTUs huggingface dataset:
Wide-Output Range Power Processing Unit for 6-kW Hall Thruster

The Japan Aerospace Exploration Agency (JAXA) has developed a power processing unit (PPU) for a 6 kW Hall thruster system. The PPU is a candidate for future mission applications, such as all-electric satellites, exploration vehicles, and orbital transfer services. The PPU has to be small and still provide a wide output range of outputs, consider the in orbit and launch environments, and manage any instability in the Hall thruster's discharge. Specifically, the four converters that make up the anode power supply of the PPU is digitally controlled to reduce the size of the control circuit. It must operate stably despite small output capacitors and long dead times. This article clarifies the design criteria for the power supply, focusing on the size of capacitors and the PI control parameters to solve these problems. The result is a compact, high-performance PPU for the 6 kW Hall thruster. The power supply meets stringent design criteria and operates the thruster stably with an output voltage that can be varied between 200 and 730 V, provide a maximum power of 5.9 kW, and offer a maximum efficiency of 96.1% in the coupling test for the 6 kW Hall thruster. The proposed PPU, including the anode power supply, achieves a power density of 0.3 kW/kg, significantly higher than that of comparable PPUs.
Stochastic dynamics and fatigue analysis of large-scale mechanical models using multilevel substructuring

An efficient methodology is presented for predicting dynamic response and fatigue life of large-scale nonlinear mechanical models, subjected to random excitation. The methodology developed is based on a combination of techniques leading to a fast and accurate determination of the dynamic response with a method related to an efficient prediction of fatigue life. Specifically, the first step involves application of an appropriate coordinate transformation, causing a drastic reduction in the degrees of freedom. This opens the way to the application of another numerical method, leading to direct determination of periodic steady-state response of nonlinear systems under periodic forcing. This approach provides a solid foundation for the subsequent application of a rainflow stress cycle counting method, leading to prediction of fatigue failure. The computational accuracy and effectiveness of the methodology is illustrated by a quite involved example model, representing a city bus subjected to road excitation. Typical results are presented for both the stochastic response and the fatigue life by considering excitation arising from selected road profiles with known statistical properties. Special attention is paid to assessing the effect of the nonlinearity, by considering profiles of different quality. Moreover, a critical comparison is performed on results referring to the expected fatigue lifetime, obtained by applying methods in both the frequency and the time domain. In this way, the applicability of classical spectral methods in nonlinear models is also investigated.
Equivalent circuits for dielectric posts in a rectangular waveguide

Scattering by dielectric posts in a rectangular waveguide is investigated by a combination of the finite and boundary element methods, and the equivalent circuits are derived. It is shown that some of the lossless dielectric post resonances in a rectangular waveguide can be physically realized by a lattice circuit, and the interaction between two posts can be evaluated by this circuit. >
An assessment of the influence of organizational characteristics on information technology adoption decision: a discriminative approach

The increasing importance of emerging information technologies has prompted many researchers to examine the nature of innovation adoption within organizations. However, the nature of organizational influences in the innovation adoption process is still not well understood. This study surveyed Business Week 1000 companies to determine whether organizational strategies, structure, or context facilitate the adoption decision of integrated services digital networks (ISDN). The results suggest that companies most receptive to ISDN are larger, less open, have more slack resources, more technology expansion actions, and fewer technology restriction actions.
Severity of Injuries to Motor Vehicle Drivers at Highway–Rail Grade Crossings in the United States

There are approximately 240,000 highway–rail grade crossings in the United States. High crash frequencies at these locations have led to continued research in safety modeling. Existing crash models for highway–rail grade crossings can be classified into two categories: models for predicting accident frequency and models of the severity of driver injuries. The majority of these studies have focused on the first category. Few studies have focused on the severity of injuries to motor vehicle drivers at highway–rail grade crossings. The objective of this study was to determine the contributing factors that influence the severity of driver injuries in accidents at highway–rail grade crossings. Probit models showed that the following factors were significant: whether the crash occurred during the peak hour, weather, visibility, vehicle type, vehicle speed, annual average daily traffic, train speed, driver age and gender, area type, and type of highway pavement. A marginal effects analysis was also conducted to quantitatively interpret the marginal effects of the contributing factors on each severity level for the highway driver.
Observing and Categorising Process Deviations in Orthopaedic Surgery

This aim of this research was to identify events in the operating theatre process (described as glitches) during elective orthopaedic operations. Two pairs of observers, each consisting of a clinician and a human factors professional, examined primary and revision hip and knee arthroplasties, arthroscopies and knee ligament reconstructions in two UK hospitals. The categorisation procedure revealed 11 key areas of glitches within the collected data. Observations of 42 operations revealed 314 glitches within the 11 categories. The rate of glitches per operation ranged from 1 to 18, with an average of 8 per operation. Most commonly observed were distractions, equipment design and technical process deviation issues. A coordinated intervention to address a range of areas could benefit the efficiency and safety of orthopaedic surgery, and there are benefits in considering the standardisation of observation studies in the operating room.
Linear and nonlinear FE analyses of a container vessel in harsh sea state

Container vessels have a challenging structural design with respect to fatigue; they are long and slender and have large openings in the deck. Their structural design in combination with high wave loads, makes these ships sensitive to fatigue damage. Classification societies mainly base their assumptions in the fatigue rules on elastic material response and the fatigue analysis is carried out using the stress-based approach. However, for harsh sea states the assumption of elastic material response is not fulfilled in local details where the stress concentration is high; cyclic plasticity may occur, which requires a strain-based fatigue assessment. The objective of this study is to present a methodology which combines the softwares Sesam and Abaqus to enable realistic hydrodynamic, structure and fatigue analyses of a container vessel in a harsh sea state. Both of the softwares are needed in order to be able to choose a solver in the structure analysis to be either linear or nonlinear, depending on the cyclic elastic or plastic material response. Analyses of a case study of a 4400 TEU (twenty-foot equivalent unit) container vessel on the North Atlantic route are presented. A long-term fatigue analysis is performed in order to search for the fatigue-critical locations in the ship. A part of the side-shell structure was chosen for a detailed study comparing results from a linear and nonlinear finite element analysis for two significant wave heights: 6.0 and 7.5 m. The results show that for both of these wave heights cyclic plasticity occurs locally, but at a very low accumulation rate, which eventually results in elastic shakedown material response. Hence, the overall conclusion is that, in the studied location, a strain-based approach to fatigue is not necessary.
SSI AND SSSI EFFECTS IN SEISMIC ANALYSIS OF TWIN BUILDINGS: DISCRETE MODEL CONCEPT

Abstract This paper presents a numerical study of soil-structure interaction (SSI) and structure-soil-structure interaction (SSSI) effects on response of twin buildings during earthquake excitations. The buildings are modeled as shear buildings and the soil is simulated by a discrete model representing a visco-elastic half-space subjected to earthquake acceleration. Equation of motion of twin buildings with different conditions, fixed based (FB), SSI and SSSI, are developed via an analytical procedure and solved numerically. Buildings responses are evaluated for aforementioned three conditions considering various soil types and compared together. One must say that soil causes change in distribution of responses throughout the buildings while ignoring soil interaction may lead to detrimental effects on buildings. Anyway, interaction between twin buildings with SSSI condition slightly mitigates soil unfavorable effects compare to one building with SSI condition. In addition, it is found that influence of so.
SecGreen: Secrecy Ensured Power Optimization Scheme for Software-Defined Connected IoV

Software-Defined Internet of Vehicles (SD-IoV) is an emerging technology that is being used in modern intelligent transportation systems (ITS). The ultimate goal of SD-IoV is to provide seamless connectivity to the end-users with low latency and high-speed data transfer. However, due to the increase in the density of the connected IoV using an open channel, i.e., the Internet, the foremost challenges of high power consumption and secure data transfer are inevitable in such an environment. An external eavesdropper may intercept the transmitted message to access the legitimate information over the public channel, i.e., the Internet. Most of the solutions reported in the literature to tackle these issues may not be applicable in the SD-IoV environment due to high computation and communication costs. Motivated from this, in this paper, the problems of high power consumption and secure data transfer in SD-IoV are formulated using mixed-integer non-linear programming (MINLP) with associated constraints. To solve the aforementioned problem, we propose a joint power optimization and secrecy ensured scheme known as SecGreen. SecGreen has an efficient energy harvesting algorithm using simultaneous wireless information and power transfer (SWIPT) to maximize the energy efficiency. Moreover, to mitigate various security attacks, a resilient lightweight secrecy association protocol is designed between vehicle and trusted gateway node of SD-IoV so that only trusted vehicles can communicate with each other and with the nearest base stations. The secrecy association protocol uses security primitives such as– physically unclonable function (PUF), one-way hash function, and bitwise exclusive OR (XOR) operations which are suitable for energy-constraint sensors in SD-IoV. The performance of the SecGreen is compared with the existing schemes, Stable & Scalable Link Optimization (SSLO), and Secure & Energy-Efficient Blockchain-enabled (SEEB) respectively. The result shows that when the number of packets across the subchannel increases, the energy consumption increases. Also, the result shows that the proposed scheme attains 22.5% and 20.34% better energy efficiency as compared to SSLO and SEEB schemes, respectively. In addition, the SecGreen scheme achieves 37.48% and 32.15% higher throughput as compared to SSLO and SEEB schemes. The results obtained show the superior performance of the proposed SecGreen scheme in comparison to these existing competitive schemes in the literature.
THE USE OF POWERPOINT IN GROUP PRESENTATIONS: INSIGHTS FROM ELT MAJORS

The current study was set out to find out the attitudes of ELT majors toward the use of PowerPoint in group presentations and how they used the software when presenting. Data was collected through the use of questionnaire, interview and class observation. The results indicate that the majority of ELT majors had positive attitudes toward the use of PowerPoint in group presentation for their user-friendly quality and multimedia functions combining audio-visual features. It was also found that group members usually prepared slides individually before one member combined all and created a slideshow. During presentations, ELT majors relied on the key points in the slides to talk but a significant number of them just read from the slides. They also claimed to make use of the archiving and display functions of PowerPoint to create activities that help reinforce and review the contents presented. From the findings, suggestions to teachers and group members to review the contents and rules to design and use well the software for group presentations were made.
Developing Housing Finance in Pakistan – Challenges and Opportunities

Expanding home-ownership poses a fundament financial challenge arising out of the long-term nature of the asset, which calls for the development of institutions and markets to facilitate the flow of long-term funds. Development of the secondary mortgage market would alleviate classical maturity mismatch and liquidity issues. The public sector can provide an enabling environment with sound macroeconomic policies, corporate governance, rule of law, and enforceability of contracts. This study draws policy implications using the empirical evidence on the determinants of mortgage depth and penetration across countries. A large part of the variation in these two dimensions across countries is explained by the level of their financial development. Development of long-term sources of funds intermediated through specialized institutions seems particularly important, as we find that the development of pension funds, which are a source of long-term funding, is strongly associated with mortgage market development. Monetary and macro-economic stability, as indicated by a low and stable rate of inflation, appears to be a strong predictor of mortgage market development. We also detect a positive relationship between the degree of competition in the financial sector and mortgage market development.
Improved pulse-width modulation and capacitor voltage-balancing strategy for a scalable hybrid cascaded multilevel converter

This study re-introduces a hybrid multilevel converter that is capable of operating independent of load power factor and modulation index plus is applicable to medium- to high-voltage application. These features are achieved by adopting a new modulation strategy that utilises third harmonic subtraction in order to: increase the modulation index linear range, have a smaller capacitor size and smaller footprint, have zero net power exchange between the cell capacitors, and the load is guaranteed for all operating conditions. This study establishes an optimal magnitude of third harmonic to be subtracted by the H-bridge cells to ensure proper converter operation. The validity of the presented modulation strategy and capacitor voltage balancing are confirmed by simulation and experimentation on a scaled-down model and prototype. The scalability of the hybrid multilevel converters to high-voltage application is demonstrated using simulation, including start-up and shut down without the need for auxiliary circuitry.
Globally important plant functional traits for coping with climate change

The last decade has seen a proliferation of studies that use plant functional traits to assess how plants respond to climate change. However, it remains unclear whether there is a global set of traits that can predict plants’ ability to cope or even thrive when exposed to varying manifestations of climate change. We conducted a systematic global review which identified 148 studies to assess whether there is a set of common traits across biomes that best predict positive plant responses to multiple climate changes and associated environmental changes. Eight key traits appear to best predict positive plant responses to multiple climate/environmental changes across biomes: lower or higher specific leaf area (SLA), lower or higher plant height, greater water-use efficiency (WUE), greater resprouting ability, lower relative growth rate, greater clonality/bud banks/below-ground storage, higher wood density, and greater rooting depth. Trait attributes associated with positive responses appear relatively consistent within biomes and climate/environmental changes, except for SLA and plant height, where both lower and higher trait attributes are associated with a positive response depending on the biome and climate/environmental change considered. Overall, our findings illustrate important and general trait-climate responses within and between biomes that help us understand which plant phenotypes may cope with or thrive under current and future climate change.
Liquid Biopsy: A New, Non-Invasive Early Diagnostic and Prognostic Tool in Oncology

: Cancer is essentially a genetic disease. Neoplastic progression consists of a subsequent series of genetic alterations that cumulate. In the bloodstream of an affected subject, circulating tumor cells (CTC) and/or small deoxy-ribonucleic acid (DNA) fragments, known as “circulating tumor DNA” (ctDNA), can be found as a consequence of cancer cells’ death. Cell-free circulating DNA (cfDNA) consists of small fragments of DNA that are found free in plasma or serum, but also in other body fluids. The term “liquid biopsy” (LB) describes a highly sensitive method (based on a simple sampling of peripheral blood) for the isolation and analysis of cfDNA, which can also contain ctDNA and CTC. Its purpose is to look for cancer cells or portions of their DNA that are circulating in the blood. LB can be used to help find cancer in an early stage. It also has the additional advantage of being largely non-invasive and, therefore, being done more frequently, allowing better tumor and genetic mutations tracking. It can also be used to validate the efficacy of a drug for cancer treatment by taking multiple samples of LB within a few weeks. This technology can also be beneficial for patients after treatment to control relapse. The aim of this work is to give an overview of this technique, from its history, state-of-the-art, and methodology of execution, to its applications in oncology and with a hint to the gynecological field.
Influence of iTax System on Service Delivery at the Kenya Revenue Authority

: iTax system provides a convenient and efficient way of improving revenue collection and transparency in fiscal administration. This study aimed at determining the effect of the i tax system on service delivery by the Kenya Revenue Authority in Eldoret Station. The study used a stratified random sampling technique to sample 37 Kenya Revenue Authority employees in Eldoret stations. The data were analyzed by use of descriptive statistics and regression techniques. The empirical results of the study showed that i Tax stability was statistically significant with a (p-value =0.003), iTax security had a significant association with service delivery (p-value=0.001), and iTax technical skills also had a substantial relationship with service delivery with a (p-value =.066). The study concluded that iTax systems affect service delivery at KRA in Eldoret station due to a robust statistical association between the iTax systems and service delivery. The study recommended that the Kenya Revenue Authority should establish tight policy measures to curb the issues associated with iTax insecurity and finally employ staff with technical knowledge and skills on the iTax system.
INDEKS KEANEKARAGAMAN JENIS SERANGGA PADA PERTANAMAN KELAPA SAWIT (Elaeis guineensis Jacq.) DI KEBUN HELVETIA PT. PERKEBUNAN NUSANTARA II

Insect Species Diversity Index in Oil Palm (Elaeis guineensis Jacq.) Planting in Helvetia Estate, PT. Perkebunan Nusantara II. The purpose of this study was to find out the insect species diversity index in oil palm (Elaeis guineensis Jacq.) planting in Helvetia Estate, PT. Perkebunan Nusantara II. This survey study was conducted from June to August 2101 in Helvetia Estate, PT. Perkebunan Nusantara II, Deli Serdang District with the altitude of ± 23 meters above sea level. The insects were caught by busing sweep net, pit fall trap, and light trap, then they were observed at the Plant Pest and Disease Laboratory, Faculty of Agriculture, University of Sumatera Utara. The result of this study showed that 298 insects consisting of 9 orders and 29 families were trapped and caught in the oil palm plantation area which has produced and 367 insects consisting of 10 orders and 34 families were trapped and caught in the oil palm plantation area which has not produced.The value of Insect Species Diversity Index according to the highest Shanon-Weiner (H’) in the oil palm plantation area which has produced is 2.9276 (adequate) and in the oil palm plantation area which has not produced is 2.9848 (adequate). While the value of Sorensen’s Quotien of Similarity for the kinds of insects in both areas is 79.365%. Keywords: Diversity index, oil palm, insect
Hybrid Modeling Approach of Car Uses in Germany on Basis of Empirical Data with Different Granularities

The use of private cars in Germany has not yet been analyzed from a longitudinal perspective: most travel surveys consider only a single day. Daily car usage is not identical over a given period because car owners use their vehicles for daily routines (e.g., commuting) as well as for infrequent events, such as holiday trips. Another problem of short-period surveys is that they underestimate the share of cars used for long-distance travel. The current work may help to improve the reliability and realism of statements about the extent to which German cars could be replaced by electric vehicles. The authors developed a hybrid modeling approach that aims to obtain car mileage per day for a full year. This approach is based on empirical data with different granularities. Input data are derived from the annually conducted German Mobility Panel, including a survey of fuel consumption and odometer readings, and the long-distance travel survey INVERMO. The study showed that 13.1% of the modeled German private car fleet never exceeded 100 km/day during a full year. Furthermore, cars were driven more than 100 km on 13.3 days/year on average. Mainly used cars (first cars) of a household were used for longer distances rather than second cars. A comparison of average mobility figures from the model approach with the Mobility in Germany national travel survey showed the model results as reliable and realistic.