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International Journal of Minerals,Metallurgy and Materials 2011年第5期18卷 615-622页

作者： Soheila Faraji Afidah Abdul Rahim Norita Mohamed Coswald Stephen Sipaut school of Chemical Sciences Universiti Sains Malaysia11800 USMPenangMalaysia school of engineering and information Technology Universiti Malaysia Sabah88999 Kota KinabaluSabahMalaysia

Cu-P-silicon carbide （SiC） composite coatings were deposited by means of electroless *** effects of pH values,temperature,and different concentrations of sodium hypophosphite （NaH2PO2·H2O）,nickel sulfate （NiSO4·6H2O）,sodium citrate （C6H5Na3O7·2H2O） and SiC on the deposition rate and coating compositions were evaluated,and the bath formulation for Cu-P-SiC composite coatings was *** coating compositions were determined using energy-dispersive X-ray analysis （EDX）.The corresponding optimal operating parameters for depositing Cu-P-SiC are as follows：pH 9;temperature,90oC;NaH2PO2·H2O concentration,125 g/L;NiSO4·6H2O concentration,3.125 g/L;SiC concentration,5 g/L;and C6H5Na3O7·2H2O concentration,50 g/*** surface morphology of the coatings analysed by scanning electron microscopy （SEM） shows that Cu particles are uniformly *** hardness and wear resistance of Cu-P composite coatings are improved with the addition of SiC particles and increase with the increase of SiC content.

关键词： electroless deposited coating electroless copper plating silicon carbide particles sodium hypophosphite hardness wear resis-tance

Spiking patterns of a hippocampus model in electric fields

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Chinese Physics B 2011年第12期20卷 484-489页

作者：门聪王江秦迎梅魏熙乐车艳秋邓斌 school of Electrical engineering and Automation Tianjin University Tianjin Key Laboratory of information Sensing and Intelligent Control Tianjin University of Technology and Education

We develop a model of CA3 neurons embedded in a resistive array to mimic the effects of electric fields from a new perspective. Effects of DC and sinusoidal electric fields on firing patterns in CA3 neurons are investigated in this study. The firing patterns can be switched from no firing pattern to burst or from burst to fast periodic firing pattern with the increase of DC electric field intensity. It is also found that the firing activities are sensitive to the frequency and amplitude of the sinusoidal electric field. Different phase-locking states and chaotic firing regions are observed in the parameter space of frequency and amplitude. These findings are qualitatively in accordance with the results of relevant experimental and numerical studies. It is implied that the external or endogenous electric field can modulate the neural code in the brain. Furthermore, it is helpful to develop control strategies based on electric fields to control neural diseases such as epilepsy.

关键词： electric field Pinsky-Rinzel neuron phase locking firing pattern

ARC-SPLINE AND ARCLET PROCESSING

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Geo-Spatial information Science 1998年第1期1卷 13-17页

作者： ZHANG Zuxun[a] BAO Xiuzhi CAO Hui [a] school of information engineering WTUSM Wuhan China 130079

This paper presents a new spline called arc *** takes two arcsconnecting adjacent points among a sampled series,with known tangental of eachsampled *** calculation for the *** curve length and the segment-ing point co... 详细信息

关键词： arc-splines computer graphics computer-aided cartography arclet processing

Numerical Study of Interaction Efficiency for a 170GHz Megawatt-Level Coaxial-Gyrotron

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Chinese Journal of Electronics 2016年第5期25卷 980-985页

作者： QIN Mimi YANG Kuo LUO Wenguang LUO Yong HUANG Yong school of Electrical and information engineering Guangxi University of Science and Technology school of Physical Electronic University of Electronics Science and Technology of China Institute of Applied physics A’ba Teachers College

The beam-wave interaction efficiency of a 170GHz megawatt-level corrugated coaxial-gyrotron operating with TE;mode was studied numerically. According to the self-consistent nonlinear theory, the efficiencies of two types of coaxial resonator were calculated and compared. Taking into account electronic velocity spread and cavity wall resistivity, the beam-wave interactions of improved cavity were investigated. The relationships between efficiency and magnetic field, voltage, current, beam radius, velocity ratio, and parameters of groove are presented. The results show that the voltage and magnetic field have great influence on efficiency, but the current and velocity spread do slightly. The optimized geometry parameters can improve efficiency, reduce the impact of velocity spread on efficiency, and achieve around 48.6% electronic efficiency and 1.7MW output power at 5% velocity spread and 6.896×10;Ωm resistivity.

关键词： Coaxial–gyrotron Corrugated Efficiency Interaction Simulation

A low-leakage and NBTI-mitigated N-type domino logic

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Journal of Semiconductors 2014年第1期35卷 129-134页

作者：梁华国徐辉黄正峰易茂祥 school of Electronic Science and Applied Physics Heifei University of Technology school of Computer and information Heifei University of Technology school of Computer Science and engineering Anhui University of Science and Technology

NBTI-induced transistor aging has become a prominent factor affecting the reliability of circuits. Reducing leakage consumption is one of the major design goals. Domino logic circuits are applied extensively in high-performance integrated circuits. A circuit technique for mitigating NBTI-induced degradation and reduce standby leakage current is presented in this paper. Two transistors are added to the standard domino circuit to pull both the dynamic node and the output up to VDo, which puts both the keeper and the inverter pMOS transistor into recovery mode in standby mode. Due to the stack effect, leakage current is reduced by the all-0 input vector and the added transistors. Experimental results reveal up to 33% NBTI-induced degradation reduction and up to 79% leakage current reduction.

关键词： domino logic circuit negative bias temperature instability leakage current standby mode

Coordinated development efficiency between cultivated land spatial morphology and agricultural economy in underdeveloped areas in China:Evidence from western Hubei province

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Journal of Geographical Sciences 2023年第4期33卷 801-822页

作者： XIANG Jingwei HAN Peng CHEN Wanxu school of Public Administration China University of GeosciencesWuhan 430074China school of Geography and information engineering China University of GeosciencesWuhan 430074China

Suitable spatial morphology of cultivated land is a basic requirement for sustaining agricultural economic development in mountainous *** development efficiency of cultivated land spatial morphology and agricultural economy(CECA)is of great practical significance to measure the efficiency of cultivated land use,and thereby promote regional rural ***,few studies to date have focused on coordinated development efficiency between cultivated land use and agricultural economy in mountainous areas from the perspective of cultivated land spatial ***,the present study explores CECA with this focus using the data envelopment analysis method,and analyzes the key influencing factors via a geographical detector model in 16 counties in western Hubei *** results show the following:(1)CECA exhibits significant spatial heterogeneity that is high in the south of the study area and low in the north;(2)scale efficiency is the primary limiting factor for CECA;(3)the insufficient output of cultivated land use mainly restricts CECA in the south of the study area,while individual county in the north suffered from input redundancy and insufficient output;and(4)population density in the southern region has the most significant effect on CECA,and gross domestic product has the greatest impact in the northern *** results contribute to the derivation of specific measures by which to promote cultivated land use efficiency and sustainable development of the social economy.

关键词： cultivated land spatial morphology agricultural economy data envelopment analysis geographical detector model coordinated development efficiency western Hubei

Numerical study on discharge characteristics influenced by secondary electron emission in capacitive RF argon glow discharges by fluid modeling

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Chinese Physics B 2018年第2期27卷 415-422页

作者：赵璐璐刘悦 Tagra Samir Key Laboratory of Materials Modification by Laser Ion and Electron Beams (Ministry of Education) School of PhysicsDalian University of Technology school of information Science and engineering Dalian Polytechnic University

A one-dimensional（1D） fluid model of capacitive RF argon glow discharges between two parallel-plate electrodes at low pressure is employed. The influence of the secondary electron emission on the plasma characteristics in the discharges is investigated numerically by the model. The results show that as the secondary electron emission coefficient increases,the cycle-averaged electric field has almost no change; the cycle-averaged electron temperature in the bulk plasma almost does not change, but it increases in the two sheath regions; the cycle-averaged ionization rate, electron density, electron current density, ion current density, and total current density all increase. Also, the cycle-averaged secondary electron fluxes on the surfaces of the electrodes increase as the secondary electron emission coefficient increases. The evolutions of the electron flux, the secondary electron flux and the ion flux on the powered electrode increase as the secondary electron emission coefficient increases. The cycle-averaged electron pressure heating, electron Ohmic heating, electron heating, and ion heating in the two sheath regions increase as the secondary electron emission coefficient increases. The cycle-averaged electron energy loss increases with increasing secondary electron emission coefficient.

关键词： RF glow discharge secondary electron emission fluid model

Fault diagnosis model based on multi-manifold learning and PSO-SVM for machinery

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仪器仪表学报 2014年第S2期35卷 210-214页

作者： Wang Hongjun Xu Xiaoli Rosen B G Key Laboratory of Modern Measurement & Control Technology Beijing Information Science & Technology University school of Mechanic and Electric engineering Beijing Information Science&Technology University Halmstad University

Fault diagnosis technology plays an important role in the industries due to the emergency fault of a machine could bring the heavy lost for the people and the company. A fault diagnosis model based on multi-manifold learning and particle swarm optimization support vector machine(PSO-SVM) is studied. This fault diagnosis model is used for a rolling bearing experimental of three kinds faults. The results are verified that this model based on multi-manifold learning and PSO-SVM is good at the fault sensitive features acquisition with effective accuracy.

关键词： fault diagnosis multi-manifold learning particle swarm optimization support vector machine

Experimental evaluation of interface states during time-dependent dielectric breakdown of GaN-based MIS-HEMTs with LPCVD-SiNχgate dielectric

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Chinese Physics B 2020年第6期29卷 419-425页

作者： Ya-Wen Zhao Liu-An Li Tao-Tao Que Qiu-Ling Qiu Liang He Zhen-Xing Liu Jin-Wei Zhang Qian-Shu Wu Jia Chen Zhi-Sheng Wu Yang Liu school of Electronics and information Technology Sun Yat-Sen UniversityGuangzhou 510275China school of Materials Science and engineering Sun Yat-Sen UniversityGuangzhou 510275China

We experimentally evaluated the interface state density of GaN MIS-HEMTs during time-dependent dielectric breakdown(TDDB).Under a high forward gate bias stress,newly increased traps generate both at the SiNx/AlGaN interface and the SiNx bulk,resulting in the voltage shift and the increase of the voltage *** prolonging the stress duration,the defects density generated in the SiNx dielectric becomes dominating,which drastically increases the gate leakage current and causes the catastrophic *** recovery by UV light illumination,the negative shift in threshold voltage(compared with the fresh one)confirms the accumulation of positive charge at the SiNx/AlGaN interface and/or in SiNx bulk,which is possibly ascribed to the broken bonds after long-term *** results experimentally confirm the role of defects in the TDDB of GaN-based MIS-HEMTs.

关键词： GaN-based MIS-HEMTs gate dielectric time-dependent dielectric breakdown interface states