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Journal of Materiomics 2024年第3期10卷 523-530页

作者： Siyuanyang Yin Qizhu Li Shaoqin wang Jiajun Chen Zirui Dong Yubo Zhang Binghui ge Jiye Zhang Jun luo School of Materials Science and engineering Shanghai University99 Shangda RoadShanghai200444China Institutes of physical Science and information technology Anhui University111 Jiulong RoadHefei230601China Minjiang Collaborative Center for Theoretical physics College of Physics and Electronic Information EngineeringMinjiang University200 Xiyuangong RoadFuzhou350108China Interdisciplinary Materials research Center School of Materials Science and EngineeringTongji University4800 Caoan RoadShanghai201804China

previous research on the ternary Ti-Fe-Sb system has revealed that stoichiometric TiFeSb cannot exist as a stable compound,whereas a single-phase TiFe_(1.33)Sb alloy with the half-Heusler-like structure has been synthesized by adding excessive *** this work,we report that TiFeSb can also be stabilized by filling additional Cu to the vacant 4d site of the half-Heusler *** experiments indicate that the TiFe-Cu_(x)Sb(x=0-0.25)samples exhibit a p-type conduction with extremely high carrier concentration((0.5-2.5)×10^(22)cm^(-3)),while these samples attain very large Seebeck coefficients,over 100 mV/K in the whole measured temperature range for the samples with x=*** addition,a logarithmic divergence of the temperature-dependent specific heat capacity(Cp/T)is observed at low temperatures,implying the strange-metal behavior of TiFeCu_(x)Sb *** partial filling of the vacant 4d site results in significantly reduced lattice thermal conductivity,leading to the low total thermal conductivity of 2.8 W·m^(-1)·K^(-1)at 823 K for the TiFeCu_(0.20)Sb ***,a dimensionless figure of merit zT of 0.54 at 923 K is realized for TiFeCu_(0.20)Sb,demonstrating that promising thermoelectric materials with intriguing physical properties can be discovered in the composition gap of half-and full-Heusler alloys.

关键词： TiFeSb Thermoelectric materials Heusler alloys Vacancy-filled

Asymmetrical Fault Current Calculation Method and Influencing Factors Analysis of Droop-Controlled Inverters

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CSEE Journal of power and Energy Systems 2024年第2期10卷 562-573页

作者： Huimin Zhao Zhikang Shuai Jun ge An luo Weimin Wu Z.John Shen college of electrical and information engineering Hunan UniversityChangsha 410006China electrical engineering Department Shanghai Maritime UniversityShanghai 201306China Department of electrical and Computer engineering Ilinois Institute of TechnologyChicagoIL 60616 USA

Since the fault dynamic of droop-controlled inverter is different from synchronous generators (SGs), protection devices may become invalid, and the fault overcurrent may damage power electronic devices and threaten the safety of the microgrid. Therefore, it is imperative to conduct a comprehensive fault analysis of the inverter to guide the design of protection schemes. However, due to the complexity of droop control strategy, existing literatures have simplified asymmetric fault analysis of droop-controlled inverters to varying degrees. Therefore, accurate fault analysis of a droop-controlled inverter is needed. In this paper, by analyzing the control system, an accurate fault model is established. Based on this, a calculation method for instantaneous asymmetrical fault current is proposed. In addition, the current components and current characteristics are analyzed. It was determined that fault currents are affected by control loops, fault types, fault distance and nonlinear limiters. In particular, the influences of limiters on the fault model, fault current calculation and fault current characteristics were analyzed. Through detailed analysis, it was found that dynamics of the control loop cannot be ignored, the fault type and fault distance determine fault current level, and part of the limiters will totally change the fault current trend. Finally, calculation and experimental results verify the correctness of the proposed method.

关键词： Asymmetrical fault analysis droop control fault current calculation method limiter transient fault characteristics

An Improved Model-based Control Scheme for Networked System

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An Improved Model-based Control Scheme for Networked System

Fuzzy Droop Control for SOC Balance and Stability Analysis of DC Microgrid with Distributed Energy Storage Systems

2010 Chinese Control and Decision Conference

作者： zhiwen wang~1,ge guo~2,dongsong luo~1 1.college of electrical and information engineering,lanzhou university of technology,lanzhou 730050,china 2.college of Automation,Dalian Maritime university,Dalian 116026,china

＜正＞To reduce the usage of the network and the requirement and occupation of the bandwidth for networked systems,an improved model-based control scheme is presented.A parameter identification module is introduced to reconstruct the model of the ***,the model-based control strategy is carried into *** examples are used to illustrate the influence of the model error on the update *** is to be noted that the smaller the model error,the larger the maximum updating time.

关键词： MB-NCSs parameter Identification Update Interval

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Journal of Modern power Systems and Clean Energy 2024年第4期12卷 1203-1216页

作者： Jipeng Gu Xiaodong Yang Youbing Zhang Luyao Xie Licheng wang Wenwei Zhou Xiaohui ge college of information engineering Zhejiang University of TechnologyHangzhou 310023China college of electrical engineering Hefei University of TechnologyHefei 230006China Electric power research Institute of State Grid Zhejiang Electric power Co. Ltd.Hangzhou 310023China

The unbalanced state of charge(SOC)of distribut-ed energy storage systems(DESSs)in autonomous DC mi-crogrid causes energy storage units(ESUs)to terminate opera-tion due to overcharge or overdischarge,which severely affects the power *** this paper,a fuzzy droop control for SOC balance and stability analysis of DC microgrid with DESSs is proposed to achieve SOC balance in ESUs while maintaining a stable DC bus ***,the charge and discharge modes of ESUs are determined based on the power supply requirements of the DC ***-dimensional fuzzy logic is then ap-plied to establish the relationship between SOC and the droop coefficient r,in the aforementioned two *** addition,when integrated with voltage-current double closed-loop con-trol,SOC balance in different ESUs is *** improve the balance speed and precision,an exponential acceleration factor is added to the input variable of the fuzzy ***,based on the average model of converter,the system-level stabil-ity of microgrid is ***/Simulink simulation re-sults verify the effectiveness and rationality of the proposed method.

关键词： DC microgrid distributed energy storage system fuzzy droop control state of charge(SOC)balance stabilityanalysis

Output Feedback of Model-based Networked Control Systems with Multi-rate Input Sampling

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Data Driven Vibration Control:A review

第二十六届中国控制会议

作者： wang zhiwen1,guo ge2,Hong Yi1,luo dongsong1 1.college of electrical and information engineering,lanzhou university of technology,lanzhou 730050,p.r.china2.college of Automation,Dalian Maritime university,Dalian 116026,p.r.china

In this paper,control problem of model-based networked control systems（MB-NCSs）with multi-rate input sampling is *** classes of transmission policies termed as perfect transmission and delay transmission are *** feedback control of the system under the two transmission policies are studied *** and sufficient conditions for system to be globally exponentially stable are derived.

关键词： MB-NCSs Lifting Technique Output Feedback

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IEEE/CAA Journal of Automatica Sinica 2024年第9期11卷 1898-1917页

作者： Weiyi Yang Shuai Li Xin luo Chongqing Institute of Green and Intelligent technology Chinese Academy of SciencesChongqing 400714 Chongqing School University of Chinese Academy of SciencesChongqing 400714China Faculty of information technology and electrical engineering University of OuluOulu 90570 VTT-technology research Center of Finland Oulu 90570Finlan college of Computer and information Science Southwest UniversityChongqing 400715China

With the ongoing advancements in sensor networks and data acquisition technologies across various systems like manufacturing,aviation,and healthcare,the data driven vibration control(DDVC)has attracted broad interests from both the industrial and academic *** shaping(IS),as a simple and effective feedforward method,is greatly demanded in DDVC *** convolves the desired input command with impulse sequence without requiring parametric dynamics and the closed-loop system structure,thereby suppressing the residual vibration *** on a thorough investigation into the state-of-the-art DDVC methods,this survey has made the following efforts:1)Introducing the IS theory and typical input shapers;2)Categorizing recent progress of DDVC methods;3)Summarizing commonly adopted metrics for DDVC;and 4)Discussing the engineering applications and future trends of *** doing so,this study provides a systematic and comprehensive overview of existing DDVC methods from designing to optimizing perspectives,aiming at promoting future research regarding this emerging and vital issue.

关键词： Data driven vibration control(DDVC) data science designing method feedforward control industrial robot input shaping optimizing method residual vibration

Detection of bursts in neuronal spike trains by the mean inter-spike interval method

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progress in Natural Science:Materials International 2009年第2期19卷 229-235页

作者： Lin Chena,b,Yong Deng c,Weihua luo a,Zhen wang a,Shaoqun Zenga,a Hubei Bioinformatics and Molecular Imaging Key Laboratory,Huazhong university of Science and technology,Wuhan 430074,china b college of Mechanical engineering,Guangxi university,Nanning,530004,china c college of Optoelectronic Science of engineering,Huazhong university of Science and technology,Wuhan 430074,china [a]Hubei Bioinformatics and Molecular Imaging Key Laboratory Huazhong University of Science and Technology Wuhan 430074 China [b]College of Mechanical Engineering Guangxi University Nanning 530004 China [c]College of Optoelectronic Science of Engineering Huazhong University of Science and Technology Wuhan 430074 China

Bursts are electrical spikes firing with a high frequency,which are the most important property in synaptic plasticity and information processing in the central nervous system. However,bursts are difficult to identify because bursting activities or patterns vary with phys-iological conditions or external stimuli. In this paper,a simple method automatically to detect bursts in spike trains is described. This method auto-adaptively sets a parameter (mean inter-spike interval) according to intrinsic properties of the detected burst spike trains,without any arbitrary choices or any operator judgment. When the mean value of several successive inter-spike intervals is not larger than the parameter,a burst is identified. By this method,bursts can be automatically extracted from different bursting patterns of cultured neurons on multi-electrode arrays,as accurately as by visual inspection. Furthermore,significant changes of burst variables caused by electrical stimulus have been found in spontaneous activity of neuronal network. These suggest that the mean inter-spike interval method is robust for detecting changes in burst patterns and characteristics induced by environmental alterations.

关键词： Inter-spike interval Bursts Spike trains Multi-electrode arrays

基于可见/近红外光谱与化学计量学的杏品种无损鉴别方法

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光谱学与光谱分析 2024年第1期44卷 44-51页

作者：高峰邢雅阁罗华平张远华郭玲塔里木大学机械电气化工程学院新疆阿拉尔843300 自治区教育厅普通高等学校现代农业工程重点实验室新疆阿拉尔843300 塔里木大学园艺与林学学院新疆阿拉尔843300 新疆生产建设兵团塔里木盆地生物资源保护利用重点实验室新疆阿拉尔843300

新疆南疆是全国杏种植面积最大的地区,杏品种繁多。在杏果品市场中,不同品种杏的品质和价格差异较大,以次充好、品质参差不齐等现象严重制约了新疆杏果业的发展。为探究利用可见/近红外光谱快速检测杏品种的可行性,基于样品的可见/近红... 详细信息

新疆南疆是全国杏种植面积最大的地区,杏品种繁多。在杏果品市场中,不同品种杏的品质和价格差异较大,以次充好、品质参差不齐等现象严重制约了新疆杏果业的发展。为探究利用可见/近红外光谱快速检测杏品种的可行性,基于样品的可见/近红外光谱与化学计量学方法,对新疆南疆地区的6个品种杏进行定性判别分析,建立一种杏品种的无损鉴别方法。采用光谱仪采集6个品种杏(“黄杏”、“橄榄杏”、“小白杏”、“小米杏”、“库买提杏”、“小吊干杏”)在350~1 000 nm(VIS/NIr)和1 000~2 500 nm(NIr)两个范围内的光谱数据,去除原始光谱首端的噪声后,对保留的光谱使用Savitzky-Golay(SG)卷积平滑和多元散射校正(MSC)处理以消除光谱存在的干扰信息,采用主成分分析(pCA)、竞争性自适应重加权算法(CArS)、随机蛙跳(rF)、连续投影算法(SpA)对原始光谱降维,结合线性判别法(LDA)、朴素贝叶斯(NB)、 K最近邻(KNN)和支持向量机(SVM)对全光谱和降维后光谱建模对比。结果表明:基于全光谱数据建立的模型有较为准确的分类结果,在VIS/NIr范围,SVM模型分类正确率为95.7%, NIr范围内,LDA模型分类正确率为97.8%;采用pCA、 CArS-SpA、 rF-SpA与SpA方法对光谱数据降维后,模型仍能保持较高的分类精度,在VIS/NIr范围,pCA-LDA模型的分类正确率为97.8%, NIr范围内,rF-SpA-LDA模型的分类正确率高达95.7%。不同模型的结果表明,VIS/NIr范围内的模型分类效果优于NIr范围内模型;4种降维方法中,pCA方法降维效果最优;4种分类器中,LDA与SVM模型的正确率高于NB与KNN模型,更适用于杏品种的鉴别。结果表明,基于VIS/NIr范围光谱结合主成分分析和线性判别法可以实现杏品种的快速无损鉴别,为杏果实的在线分拣鉴定提供了新途径。

关键词：可见光光谱近红外光谱化学计量学杏品种鉴别

A computational investigation of boron-doped chromium and chromium clusters by density functional theory

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Science china(physics,Mechanics & Astronomy) 2010年第5期53卷 812-817页

作者： ge GuiXian1,JING Qun1 & luo YouHua2,3 1 Key Laboratory of Ecophysics and Department of physics,Normal college,Shihezi university,Xinjiang 832003,china 2 School of Science,East china university of Science and technology,Shanghai 200237,china 3 Institute of Theoretical physics,School of physics and information Optoelectronics,Henan university,Kaifeng 475004,china 1. Key Laboratory of Ecophysics and Department of physics Normal College Shihezi University Xinjiang 832003 China2. School of Science East China University of Science and Technology Shanghai 200237 China3. Institute of Theoretical Physics School of Physics and Information Optoelectronics Henan University Kaifeng 475004 China

The geometries,stabilities and electronic properties of Crn and CrnB(n=2-9) clusters have been systematically investigated by density functional *** results suggest that the lowest energy structures for CrnB clusters can be obtained by substituting one Cr atom in Crn+1 clusters with B *** geometries of CrnB clusters are similar to that of Crn+1 clusters except for local structural *** second-order difference and fragmentation energy show Cr4,Cr6,Cr8,Cr3B,Cr5B and Cr8B cluster are the most stable among these studied *** impurity B increases the stabilities of chromium *** B is doped on the Crn clusters,cluster geometry does dominate positive role in enhancing their *** doped B atom does not change the coupling way of the Cr site in Crn clusters,but breaks the symmetry and the Cr atoms are no longer *** doped B atom increases the total magnetic moments of Crn in most cases.

关键词： Crn and CrnB clusters geometries electronic properties