bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design of droop controller in islanded microgrids using multi‐objective optimisation based on accurate small‐signal model
Authors: Shi Yuntao , Gu Xiang , Yin Xiang , Feng Shun , Zhang Shufeng 
Published: April 2022

AbstractThe inaccuracy of power sharing is a classic problem of droop control when an islanded AC microgrid suffers from high loads and line impedance differences. It degrades system performance and even destroys system stability. This paper originally presents a multi‐objective optimisation droop control method to solve such a problem. And three objective functions are presented according to the characteristics of microgrids. First, a complete small‐signal model of a microgrid in autonomous operation mode is established. Next, this paper derives constraint conditions for the stable microgrid. Then, this paper originally designs three objective functions for constructing a multi‐objective optimisation (MOO) problem to improve control performance. The multiobjective evolutionary algorithm based on decomposition (MOEA/D) is used to obtain the Pareto optimal frontier of the MOO problem. The fuzzy affiliation function method is used to choose the best solution from the generated Pareto optimal frontier. Finally, simulations verified the validity and superiority of the presented method.
Analysis of the non‐isolated step‐up network based on impedance source converter
Authors: Alizadeh Darioush , Babaei Ebrahim , Sabahi Mehran 
Published: April 2022

AbstractA new topology of the high step‐up Z‐source converter is proposed, which does not need to work at high duty cycles to increase the voltage gain. In other words, this converter can generate high voltage gain in low duty cycles. In addition to these advantages, the converter has advantages such as low voltage stress across the passive components, common ground between the input and output, and continuous input current. The proposed converter will be analysed in shoot‐through and non‐shoot‐through operating modes, and then, the minimum size of the used elements in the converter will be calculated and designed, then the loss analysis has occurred. Finally, the experimental results are presented to validate the claims, and the closed‐loop control is given for the proposed converter.
Evaluation of solar radiation models on vertical surface for building photovoltaic applications in Beijing
Authors: Li Fen , Wang Renkui , Mao Ling , Zhu Donghai , She Xu , Guo Jianping , Lin Shunfu , Yang Yongheng 
Published: April 2022

AbstractBuilding photovoltaic (PV) may provide a growing share of electricity for big cities. However, lack of measured radiation data on vertical surface remains a critical problem for building PV deployment. With the development of urbanization and industrialization, high aerosol load is altering the nature of solar radiation in Beijing. Hence, ten in‐plane solar radiation models are reviewed to choose optimal model for calculating solar radiation on vertical surface in such high turbidity area. At the same time, the effect of atmospheric turbidity on the model accuracy is revealed for further understanding on the optimal model. To give general suggestion on model selection, the performance of the ten models for each weather type is tested based on new method of weather type classification. Finally, solar resource on vertical surface and output energy of building PV system are evaluated by the optimal model to guide building PV deployment. The results indicate that Perez model is suitable to calculate solar radiation on vertical surface in high turbidity area. High atmosphere turbidity will cause Perez model inaccurate. Model selection can be made by the status of atmospheric transmittance. It is feasible to apply building PV in Beijing with AC output energy of 630–971 kWh/kWp/year.
A prior information‐based coverage path planner for underwater search and rescue using autonomous underwater vehicle (AUV) with side‐scan sonar
Authors: Cai Chang , Chen Jianfeng , Yan Qingli , Liu Fen , Zhou Rongyan 
Published: April 2022

AbstractThe coverage path planning (CPP) technique attracts growing interest in studies on underwater search and rescue (SAR) conducted with an autonomous underwater vehicle (AUV) equipped with a side‐scan sonar (SSS). In SAR missions, prior information is crucial. Aiming at the underwater SAR mission with prior information, a new coverage path planner (SAR‐A*) is proposed. The ultimate goal is to generate a feasible path for completely covering the task area and preferentially visiting more valuable cells with fewer turns. First, the whole task area is decomposed into hexagon cells as waypoints to be visited for complete coverage. Second, the probability of discovering the target is obtained according to the target presence probability and the SSS detection ability. Under the assumption of prior target information, the target presence probability is modelled as a two‐dimension Gaussian distribution based on predicted target locations or trajectories. Then, an optimal next‐waypoint selection process is formulated as a multi‐objective decision‐making problem and solved by the weighted metric method. Finally, simulation and experimental results demonstrate that the generated path can improve the cumulative probability of discovering the target with fewer turns.
A fine frequency estimation algorithm based on DFT samples and fuzzy logic for a real sinusoid
Authors: He Yigen , Shi Xuesen , Wang Yongqing , Shen Yuyao 
Published: April 2022

AbstractThe study on the frequency estimation of a real sinusoid has been addressed in this article. Discrete‐Fourier‐transform (DFT)‐based frequency estimation always uses the maximum bin of DFT as a coarse estimation followed by a fine estimation algorithm, which computes a correction term to compensate for the initial frequency offset caused by the coarse estimation. To enhance the frequency estimation accuracy, a fine estimation algorithm based on DFT samples and fuzzy logic (FL) is proposed in this study. Firstly, a modified phase‐based algorithm is presented to estimate the sign of the correction term. Then, a main‐lobe coefficient and a side‐lobe coefficient are constructed using the amplitude of three spectral lines to calculate the correction term. A FL controller is utilised to generate a weighted factor to adjust the weight of the main‐lobe coefficient and the side‐lobe coefficient in the formula of the correction term. Compared with other existing fine algorithms, the proposed algorithm improves the correct probability of sign estimation by 10%–20%, and improves the estimation accuracy by 5%–8% at lower carrier‐to‐noise ratios (CNRs). In addition, the performance of the proposed algorithm is less affected by the initial frequency offset than other algorithms.
Impact of guidewire caliber on ERCP outcomes: Systematic review and meta-analysis comparing 0.025- and 0.035-inch guidewires
Authors: Aziz Muhammad , Iqbal Amna , Ahmed Zohaib , Saleem Saad , Lee-Smith Wade , Goyal Hemant , Kamal Faisal , Alastal Yaseen , Nawras Ali , Adler Douglas G. 
Published: April 2022

Abstract
Background and study aims The impact of guidewire caliber on endoscopic retrograde pancreatography (ERCP) outcomes are not clear. Recent studies have compared two guidewires, 0.035- and 0.025-inch, in randomized controlled trials (RCTs). We performed a systematic review and meta-analysis of available RCTs to assess if different caliber would change the outcomes in ERCP.
Patients and methods A systematic search of PubMed/Medline, Embase, Cochrane, SciELO, Global Index Medicus and Web of Science was undertaken through November 23, 2021 to identify relevant RCTs comparing the two guidewires. Binary variables were compared using random effects model and DerSimonian-Laird approach. For each outcome, risk-ratio (RR), 95 % confidence interval (CI), and P values were generated. P < 0.05 was considered significant.
Results Three RCTs with 1079 patients (556 in the 0.035-inch group and 523 in the 0.025-inch group) were included. The primary biliary cannulation was similar in both groups (RR: 1.02, CI: 0.96–1.08, P = 0.60). The overall rates of PEP were also similar between the two groups (RR: 1.15, CI: 0.73–1.81, P = 0.56). Other outcomes (overall cannulation rate, cholangitis, perforation, bleeding, use of adjunct techniques) were also comparable.
Conclusions The results of our analysis did not demonstrate a clear benefit of using one guidewire over other. The endoscopist should consider using the guidewire based on his technical skills and convenience.
Liver, NAFLD and COVID-19
Authors: Hoffmann Carlotta , Gerber Philipp A. , Cavelti-Weder Claudia , Licht Louisa , Kotb Reham , Al Dweik Rania , Cherfane Michele , Bornstein Stefan R. , Perakakis Nikolaos 
Published: April 2022

AbstractCoronavirus disease 2019 (COVID-19) is characterized by a wide clinical spectrum
that includes abnormalities in liver function indicative of liver damage.
Conversely, people with liver diseases are at higher risk of severe COVID-19. In
the current review, we summarize first the epidemiologic evidence describing the
bidirectional relationship between COVID-19 and liver function/liver
diseases. Additionally, we present the most frequent histologic findings as well
as the most important direct and indirect mechanisms supporting a COVID-19
mediated liver injury. Furthermore, we focus on the most frequent liver disease
in the general population, non-alcoholic or metabolic-associated fatty liver
disease (NAFLD/MAFLD), and describe how COVID-19 may affect
NAFLD/MAFLD development and progression and conversely how
NAFLD/MAFLD may further aggravate a COVID-19 infection. Finally, we
present the long-term consequences of the pandemic on the development and
management of NAFLD.
Personality and the Subjective Assessment of Hearing Aids
Authors: Cox Robyn M. , Alexander Genevieve C. , Gray Ginger 
Published: April 2022

AbstractRelatively little is known about the influence of patients' personality features on the responses they make to self-assessment items used to measure the outcome of a hearing aid fitting. If the personality of the hearing aid wearer has a significant influence on self-report outcome data, it would be important to explore the relevant personality variables and to be cognizant of their effects when using subjective outcome data to justify decisions about clinical services or other matters. This investigation explored the relationship between several personality attributes and responses to the Abbreviated Profile of Hearing Aid Benefit (APHAB). It found that more extroverted patients tend to report more hearing aid benefit in all speech communication situations. In addition, patients with a more external locus of control tend to have more negative reactions to loud environmental sounds, both with and without amplification. Anxiety also played a small additional role in determining APHAB responses. Although personality variables were found to explain a relatively small amount of the variance in APHAB responses (usually around 10%), these outcomes should alert practitioners and researchers to the potential effects of personality variables in all self-report data.
Abbreviations: ANX = anxiety; APHAB = Abbreviated Profile of Hearing Aid Benefit; AV = APHAB subscale Aversiveness; BN = APHAB subscale Background Noise; EC = APHAB subscale Ease of Communication; EIP = extroversion-introversion preference; MBTI = Myers-Briggs Type Indicator; PO = belief in powerful others; RV = APHAB subscale Reverberation; Self = belief in internal control; SRT = speech reception threshold; STAI = State-Trait Anxiety Inventory
Dimensions of Hearing Aid Outcome
Authors: Humes Larry E. 
Published: April 2022

AbstractDimensions of hearing aid outcome are explored in this paper. First, a variety of hearing aid outcome measures is defined including objective and subjective performance, objective and subjective benefit, satisfaction, and use. Following the definition of these terms, factor analysis is described as a statistical tool that can be of assistance in establishing the number and nature of the relevant dimensions of hearing aid outcome. Next, the results from three recent studies that included a variety of measures of hearing aid outcome are examined and factor analysis is applied to the data from each study. This examination leads to the conclusion that hearing aid outcome is a multidimensional construct, rather than unidimensional. The most complete description of hearing aid outcome will be obtained when including at least one measure of aided speech recognition performance, one or more measures of objective benefit in speech recognition, one or two subjective measures of sound quality or listening effort, and one measure of either subjective benefit, satisfaction, or use.
Abbreviations: COSI = Client-Oriented Scale of Improvement; CST = Connected Speech Test; HAPI = Hearing Aid Performance Inventory; HHIE = Hearing Handicap Inventory for the Elderly; ITC = in the canal; PHAB = Profile of Hearing Aid Benefit; REAR = real-ear aided response; REIG = real-ear insertion gain; REUR = real-ear unaided response
Some Limitations of Evaluative Investigations Based Solely on Normed Outcome Measures
Authors: Gagné Jean-Pierre , McDuff Stéphane , Getty Louise 
Published: April 2022

AbstractThe present article argues that evaluative research in audiologic rehabilitation should be consistent with contemporary conceptual frameworks of rehabilitation. Moreover, comprehensive evaluative research investigations should include an evaluation of (1) the process of intervention and (2) the impacts and consequences of the intervention program. An approach to rehabilitation based on the principle that intervention should be viewed as a solution-centered problem-solving process is outlined. Then, three illustrative cases are described and compared from the perspective of traditional evaluative research paradigms and from the perspective that audiologic rehabilitation is a solution-centered problem-solving process. Some shortcomings of traditional approaches to evaluative research are discussed. Finally, some guidelines that could lead to the development of comprehensive evaluative research in rehabilitation are outlined.
Public Works Programmes and Cooperation for the Common Good: Evidence from Malawi
Authors: Beierl Stefan , Dodlova Marina 
Published: April 2022

AbstractThis paper investigates the relationship between Malawi’s largest and oldest public works programme (PWP) and social cohesion, specifically within-community cooperation for the common good. Using both primary and secondary data, we show that public works are associated with higher coordination activities and higher voluntary (unpaid) contributions to public goods, along both vertical ties (between community members and local leaders) and horizontal ties (among community members). Especially for school-building activities, voluntary inputs in the form of labour and other in-kind contributions are higher in the presence of the PWP. Our results contribute to a better understanding of the link between social protection programmes with community-driven features and social cohesion.
Attitude measurement of multi-DOF actuator based on multiple-inputs and single-output WPT system modeling
Authors: Gao Shihao , Wang Qunjing , Li Guoli , Qian Zhe , Ye Qiubo , Li Zheng 
Published: April 2022

Abstract
Multi-DOF actuators are used in bionics where their flexibility is limited by changing batteries or wired charging methods. In order to realize flexible power supplement and accurate attitude measurement, a multiple-inputs and single-output wireless power transmission (WPT) attitude measurement method is proposed. Traditional contact measurement methods have large friction resistance, and some non-contact measurement methods are complicated in structure or calculation. In order to solve the above problems, the receiving coil is installed inside the rotor. When the rotor rotates, the receiving angle is offset from the multi-transmitting coil outside the stator. The receiving coil can transmit power with multi-angle rotation and has good space tolerance. The rotor position is measured by estimating mutual inductance accurately. This method effectively reduces the time of finite element analysis. Three types of exercise are tested (yaw, spin, and tilt). Compared with micro-electromechanical system and fast complementary filter methods, the average angle error of the proposed WPT method is reduced by 36%, 24% and 40% respectively, and the initial attitude error is about 50% of that of the other two methods. Experiments show that this method can accurately measure the attitude of the rotor of the multi-DOF actuator.
System of cracks under the impact of plane elastic waves
Authors: Popov V G 
Published: April 2022

Abstract
The problem of determining the two-dimensional diffraction field and the stress state arising from the interaction of elastic waves with a system of arbitrarily located cracks is solved. Cracks are located in an unbounded elastic medium which is in a plane deformation state. The method of solution is based on the use of discontinuous solutions of the equations of motion of elastic media and the reduction of the original problem to a system of singular integro-differential equations. The obtained systems are solved numerically the mechanical quadrature method.
Study of negative ion beam emittance characteristic using 3D PIC-MCC simulation
Authors: Miyamoto K. , Nagaoka K. , Hatayama A. , Hoshino K. , Nakano H. , Shibata T. , Tsumori K. 
Published: April 2022

Abstract
It is reported from the measurement of a negative ion beamlet emittance that the characteristic three-Gaussian components are observed in the emittance diagram. The negative ion trajectories are calculated using 3D PIC-MCC simulation in order to clarify the origin of this complicated phase space structure and underlying physical mechanism. The characteristic three-Gaussian components can be reproduced in the emittance diagram from the simulation result. It is verified that the Gaussian components are caused by the negative ions extracted from the different plasma meniscus region, that is, the central region or the region near the edges of the meniscus.
Low-voltage extraction characteristics of ion beams and space potential measurements on ECRIS
Authors: Owada I , Kubo W , Harisaki S , Tsuda K , Sato K , Anan M , Maenaka T , Kato Y 
Published: April 2022

Abstract
We have been using an electron cyclotron resonance ion source (ECRIS) for ion beam production, and it is desirable to construct a universal ECRIS that can produce ions with a wide range of mass/charge ratios, e.g. from several to several thousand. We investigated the characteristics of ions with high mass/charge ratios, e.g., iron endohedral fullerenes production, which requires low voltage beam extraction. We investigated the characteristics of the ion beam extraction at low extraction voltage. It is found that the beam current almost obeyed the Child-Langmuir law for various ion species. The space potential of the plasma in the ion source can be obtained from the relation between the extraction voltage and the square of the magnetic field strength of the dipole magnet. It is found that space potential values are larger with large charge state of ions, in low gas pressure condition and in high microwave incident power. At the same time, the plasma space potential was measured by using a Langmuir probe and compared with the ion beam method. It is found that same trend is confirmed with probe method.
Ground-level ozone pollution in China: a synthesis of recent findings on influencing factors and impacts
Authors: Wang Tao , Xue Likun , Feng Zhaozhong , Dai Jianing , Zhang Yingnan , Tan Yue 
Published: April 2022

Abstract
Ozone (O3) in the troposphere is an air pollutant and a greenhouse gas. In mainland China, after the Air Pollution Prevention and Action Plan was implemented in 2013—and despite substantial decreases in the concentrations of other air pollutants—ambient O3 concentrations paradoxically increased in many urban areas. The worsening urban O3 pollution has fuelled numerous studies in recent years, which have enriched knowledge about O3-related processes and their impacts. In this article, we synthesise the key findings of over 500 articles on O3 over mainland China that were published in the past six years in English-language journals. We focus on recent changes in O3 concentrations, their meteorological and chemical drivers, complex O3 responses to the drastic decrease in human activities during coronavirus disease 2019 lockdowns, several emerging chemical processes, impacts on crops and trees, and the latest government interventions.
Local random vector model for semiclassical fractal structure of chaotic resonance states
Authors: Clauß Konstantin , Ketzmerick Roland 
Published: April 2022

Abstract
The semiclassical structure of resonance states of classically chaotic scattering systems with partial escape is investigated. We introduce a local randomization on phase space for the baker map with escape, which separates the smallest multifractal scale from the scale of the Planck cell. This allows for deriving a semiclassical description of resonance states based on a local random vector model and conditional invariance. We numerically demonstrate that the resulting classical measures perfectly describe resonance states of all decay rates γ for the randomized baker map. By decreasing the scale of randomization these results are compared to the deterministic baker map with partial escape. This gives the best available description of its resonance states. Quantitative differences indicate that a semiclassical description for deterministic chaotic systems must take into account that the multifractal structures persist down to the Planck scale.
Spatial and temporal patterns of electric vehicle charging station utilization: a nationwide case study of Switzerland
Authors: Gellrich Mario , Block Andreas , Leikert-Böhm Ninja 
Published: April 2022

Abstract
The expansion of the public charging infrastructure for electric vehicles is seen as central to the development of electric mobility in many countries. Although national studies of charging infrastructure utilization based on real-world data would be a sound basis for demand planning, such studies are scarce. Using Switzerland as an example, this study examines the spatial and temporal patterns of charging infrastructure utilization. To this end, detailed, nationwide, real-time utilization data from 3086 electric vehicle supply equipment units (EVSEs) at electric vehicle charging stations were collected over a period of several months and analyzed exploratively and statistically. The maximum average utilization rate of the EVSEs surveyed during the study period is between 14% and 16%, depending on the day of the week and time of day. Most charging occurs Monday through Friday during peak working hours and on Saturday during the day. The median utilization time is higher in the largest cities than the statewide average. Charging stations along major transit routes do not have higher utilization rates than in other locations. The results suggest that public charging infrastructure is used primarily in cities and agglomeration during work hours. The findings from this study may help plan and make better use of funding to expand charging infrastructure.