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A New Method for Studying the Distribution of Induced Defects in Potential Wells in a-Si : H/a-SiN_(x) : H Multilayer

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Chinese Physics Letters 1994年第9期11卷 573-576页

作者： WANG Zhichao GUO Shengkang CAO Guorong chen cai SUN Meixiang Department of Physics Nanjing UniversityNanjing 210008

The induced defects and their distribution in a-Si:H/a-SiN_(x):H multilayers can be determined by use of electromagnetic *** is found that the distributions of the induced defects in the interface regions on both sides of the a-Si:H sublayer are asymmetric and related to the growth direction of the film;a large number of induced defects exist in the interface region away from substrate,but few or no in the interface region near substrate.

关键词： technique. interface (x)

Mitigation measures of the electric field in the medium-voltage power module:Effect of voltage types and recommendations for designers

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High Voltage 2021年第5期6卷 836-849页

作者： Zhizhao Huang cai chen Yong Kang Stig Munk-Nielsen Christian Uhrenfeldt State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and TechnologyWuhanChina Department of Energy Technology Aalborg UniversityAalborgDenmark

In the medium‐voltage silicon carbide device power module,the higher voltage level will induce higher electric field stress in critical internal points such as the edge of the conductor on the direct bonded copper(DBC)*** can lead to partial discharge and subsequently accelerated ageing of the insulating medium in the ***,it is important to reduce the high electric field ***,the related technical methods of electric field control are reviewed and compared by combining the ease of implementation in real power module and the field control *** addition,systematic explanations of the electric field drift and influencing factors of the electric field strength under different voltage types within different module structures are ***,for half‐bridge power modules with different substrates structures,sug-gestions on how to implement non‐linear field‐dependent materials to reduce the electric field strength are given.

关键词： power field measures

Shape Optimization for A Conventional Underwater Glider to Decrease Average Periodic Resistance

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China Ocean Engineering 2021年第5期35卷 724-735页

作者： LI Jing-lu WANG Xin-jing WANG Peng DONG Hua-chao chen cai-hua School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an 710072China

As a type of autonomous underwater vehicle(AUV),underwater gliders(UG)are getting increasing attention in ocean *** save energy and satisfy the mission requirements of a longer voyage,shape optimization for UGs has become a key technique and research *** this paper,a conventional UG,including its fuselage and hydrofoil,is optimized,which aims to decrease the average resistance in one motion *** operate the optimization progress for the complex object,multiple free form deformation(FFD)volumes are established for geometric ***-fidelity simulation models are employed for objective function evaluation and gradients *** sequential quadratic programming(SQP)method is adopted as an optimization *** optimization results show that there exists a UG with symmetrical and non-horizontal hydrofoils that has lower resistance.

关键词： underwater glider shape optimization conventional configuration free form deformation

Binding interactions of pefloxacin mesylate with bovine lactoferrin and human serum albumin

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第6期7卷 452-458页

作者： FAN Ji-cai chen Xiang WANG Yun FAN cheng-ping SHANG Zhi-cai Department of Chemistry Zhejiang University Hangzhou 310027 China

The binding of pefloxacin mesylate （PFLX） to bovine lactoferrin （BLf） and human serum albumin （HSA） in dilute aqueous solution was studied using fluorescence spectra and absorbance spectra. The binding constant K and the binding sites n were obtained by fluorescence quenching method. The binding distance r and energy-transfer efficiency E between pefloxacin mesylate and bovine lactoferrin as well as human serum albumin were also obtained according to the mechanism of Forster-type dipole-dipole nonradiative energy-transfer. The effects of pefloxacin mesylate on the conformations of bovine lactoferrin and human serum albumin were also analyzed using synchronous fluorescence spectroscopy.

关键词： Pefloxacin mesylate (PFLX) Bovine lactoferrin (BLf) Human serum albumin (HSA) Fluorescence spectra Energy-transfer efficiency

Physical modeling and validation of porpoises' directional emission via hybrid metamaterials

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National Science Review 2019年第5期6卷 921-928页

作者： Erqian Dong Yu Zhang Zhongchang Song Tianye Zhang chen cai Nicholas X.Fang Key Laboratory of Underwater Acoustic Communication and Marine Information Technology of the Ministry of Education College of Ocean and Earth SciencesXiamen University Department of Mechanical Engineering Massachusetts Institute of Technology State Key Laboratory of Marine Environmental Science Xiamen University Biology Department Woods Hole Oceanographic Institution

In wave physics and engineering, directional emission sets a fundamental limitation on conventional simple sources as their sizes should be sufficiently larger than their *** metamaterial and animal biosonar both show potential in overcoming this *** metamaterials arranged in periodic microstructures face great challenges in realizing complex and multiphase biosonar ***, we proposed a physical directional emission model to bridge the gap between porpoises’ biosonar and artificial *** by the anatomical and physical properties of the porpoise’s biosonar transmission system, we fabricated a hybrid metamaterial system composed of multiple composite *** validated that the hybrid metamaterial significantly increased directivity and main lobe energy over a broad bandwidth both numerically and *** device displayed efficiency in detecting underwater target and suppressing false target *** metamaterial-based physical model may be helpful to achieve the physical mechanisms of porpoise biosonar detection and has diverse applications in underwater acoustic sensing, ultrasound scanning, and medical ultrasonography.

关键词： porpoise’s physical model metamaterials biosonar directional emission

Intermediate-depth earthquakes beneath the Pamir-Hindu Kush Region:Evidence for collision between two opposite subduction zones

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Earthquake Science 2009年第6期22卷 659-665页

作者： Xiaoting Lou chen cai Chunquan Yu Jieyuan Ning Department of Geophysics School of Earth and Space Sciences Peking University Beijing 100871 China

We employed a double-difference algorithm （hypoDD） to relocate earthquakes within the region bounded by 66°E-78°E and 32°N-42°N in the period of 1964-2003 reported by the International Seismological Center （ISC）. The improved hypocentral locations delineate a double-layered Wadati-Benioff zone in the eastern Hindu Kush intermediate seismic belt. Based on this feature and other evidences, we propose that the intermediate-depth earthquakes beneath the Pamir-Hindu Kush region may occur in two collided subduction zones with opposite dip directions.

关键词： continental dynamics Pamir-Hindu Kush intermediate seismic zone earthquake relocation

Optimization and test for structural parameters of UAV spraying rotary cup atomizer

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International Journal of Agricultural and Biological Engineering 2017年第3期10卷 78-86页

作者： Zhou Qingqing Xue Xinyu Qin Weicai cai chen Zhou Liangfu Nanjing Research Institute for Agriculture Mechanization Ministry of AgricultureNanjing 210014China

Small unmanned aerial vehicle(UAV)pesticide application technology is developing rapidly in ***,the spray efficiency of UAV sprayer is not stable,one important reason is that the lack of specialized aviation *** cup atomizer is not easily to be blocked and has broad application foreground in UAV *** order to obtain good spraying quality and narrow droplet spectrum aviation spraying centrifugal nozzle,the impacts of rotary cup atomizer structural parameters on atomization property were *** this research,a centrifugal atomization test device was designed,on which a frequency converter was used to adjust the rotary speed,and a return valve was used to stabilize the flow rate and pressure of spray *** droplet volume medium diameter(VMD)and droplet spectrum relative width(SRW)were tested by using laser particle analyzer and particle analysis *** analysis results of variance and quadratic regression orthogonal test were used to optimize the structural parameters of rotary cup *** influences of rotary cup atomizer structural parameters on atomization property,such as groove shape,diameter,teeth number,cone angle and height were evaluated and analyzed by conducting single-factor *** results showed that:the best optimized rotary groove shape was square,diameter and teeth number had significant effects on droplet VMD and SRW,while cone angle had no effect on the droplet VMD and SRW,height affected droplet VMDbut did not affect droplet ***,diameter and teeth number were selected as the variables of quadratic regression orthogonal test,droplet VMD and SRW regression model was established by using response surface analysis *** optimized structural parameters respectively were:groove shape square,cone angle 60°,height 20 mm,diameter 61.5 mm and teeth number *** VMD and SRW simulation value respectively were 200μm and *** differences between simulation value and test value were 0.68%and 9.90

关键词： rotary cup atomizer atomization droplet VMD droplet SRW optimization mathematical model response surface

Mathematical modeling on multi-stage series crushing ratio distribu- tion based on fuzzy physical programming

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Journal of Coal Science & Engineering(China) 2013年第2期19卷 262-267页

作者： Yu-Long QI chen-chen cai Ping-Zhen LANG Jiangsu Xuzhou Construction Machinery Institute Xuzhou 221004 China Beijing General Research Institute of Mining and Metallurgy Beijing 100160 China

Double-layer, multi-roller plate crusher is a new device, that uses a multi-stage series crushing style to break particles, with the crushing ratio distribution directly influencing the machine＇s performance. Three crushing ratios of 2.25, 2.15 and 2.01, used for fuzzy physical programming, were determined. The comparison of the optimized result between the double-layer multi-roller plate crusher and a high pressure roll grinder showed that the double-layer multi-roller plate crusher had a better performance, reducing crushing force and wear.

关键词： fuzzy physical programming double-layer multi-roller plate crushing multi-stage series crushing crushing ratio

Power transformer fault diagnosis considering data imbalance and data set fusion

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High Voltage 2021年第3期6卷 543-554页

作者： Yang Zhang Hong cai chen Yaping Du Min chen Jie Liang Jianhong Li Xiqing Fan Xin Yao Department of Building Service Engineering Hong Kong Polytechnic UniversityHong KongChina Academy for Advanced Interdisciplinary Studies and Department of Electrical and Electronic Engineering Southern University of Science and TechnologyShenzhenChina Research Institute State Grid Zhejiang Electric Power Co.LtdHangzhouChina Zhejiang Huayun Information Technology Co. LtdHangzhouChina State Grid Zhejiang Electric Power Co. LtdLishui Power Supply BureauLishuiChina Guangdong Provincial Key Laboratory of Brain‐inspired Intelligent Computation Department of Computer Science and EngineeringSouthern University of Science and TechnologyShenzhenChina

Improving the accuracy of transformer dissolved gas analysis is always an important demand for power ***,the requirement for large numbers of fault samples becomes an obstacle to this *** article creatively uses a large number of health data,which is much easier to obtain by power companies,to improve diagnosis *** investigations from the view of both data set and methodology to deal with this problem are presented.A data set consists of 9595 health samples and 993 fault samples is used for *** characteristics of the data set and the influence of the health data on diagnostic accuracy are *** performance of many state‐of‐art algorithms that handle the imbalanced prob-lem is ***,an efficient fault diagnosis algorithm named self‐paced ensemble(SPE)is *** SPE,classification hardness is proposed to include the data characteristic in the *** method can guarantee the diversity of the data set and keep high *** to the experiment results,the superior of SPE is confirmed and also proves that involving more health samples can improve transformer diagnosis when fault data are limited.

关键词： handle fault diagnosis