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Science China(Physics,Mechanics & Astronomy) 2010年第3期53卷 465-468页

作者： ZHANG YuChao1, XING ZhiGang2, MA ZiGuang2, CHEN Yao2, DING GuoJian2, XU PeiQiang2, DONG ChenMing3, CHEN Hong2 & LE XiaoYun1 1 school of Physics and Nuclear Energy Engineering, Beihang university, Beijing 100190, China 2 Renewable Energy Laboratory, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China 3 school of information and communication, tianjin polytechnic university,{4., China 1. school of Physics and Nuclear Energy Engineering Beihang University Beijing 100190 China2. Renewable Energy Laboratory Institute of Physics Chinese Academy of Sciences Beijing 100190 China3. School of Information and Communication Tianjin Polytechnic University Tianjin 300160 China

GaN epifilms are grown on the patterned sapphire substrates (PSS) (0001) and the conventional sapphire substrates (CSS) (0001) by metal-organic chemical vapor deposition (MOCVD) using a novel two-step growth. High resolution X-ray diffraction (HR-XRD) is used to investigate the threading dislocation (TD) density of the GaN epifilms. The TD density is calculated from the ω-scans full width at half maximum (FWHM) results of HR-XRD. The edge dislocation destiny of GaN grown on the PSS is 2.7×108 cm-2, which is less than on the CSS. This is confirmed by the results of atomic force microscopy (AFM) measurement. The lower TD destiny indicates that the crystalline quality of the GaN epifilms grown on the PSS is improved compared to GaN epifilms grown on the CSS. The residual strains of GaN grown on the PSS and CSS are compared by Raman Scattering spectra. It is clearly seen that the residual strain in the GaN grown on PSS is lower than on the CSS.

关键词： GaN patterned sapphire substrate threading dislocation XRD

A New Joint Elongation Detection Algorithm of the Conveyer Belt

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工程科学（英文版） 2007年第3期5卷 101-104页

作者： Geng Lei,Miao Changyun(information & communication of Engineering school.tianjin{4. university,tianjin,300160)

There is a considerable interest in the image processing method of the joint of the conveyer belt with steel *** paper presents a significant development of the joint's elongation judgment based on template matching and statistics which provides more accurate local information compared to the algorithms in the references,and shows a reliable,real-time performance.

关键词： conveyer belt template matching B-splint curve fit

Simulation and Design of a High Responsibility PIN Photodetector

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Semiconductor Photonics and Technology 2010年第Z1期 92-97页

作者： GENG Boyun,LI Xiaoyun,NIU Pingjuan(school of information and communication Engineering,tianjin{4. university,tianjin 300160,CHN)

A silicon-based PIN photodetector structure with the characteristics of high responsibility and high cut-off frequency fabricated with the PERL(the passivated emitter and the rear locally-diffused)technologies is introduced in this *** making some tiny adjustments of the structure,Silvaco software is used to simulate three similar structures of PIN photodetector by measuring the spectral response,dark current,cut-off frequency and dc *** the results,it is concluded that PIN photodetector with the middle shallow diffusion area is superior to the other two ones in dark current,at least 35% *** responsibility of these three kinds of detector reaches the degree of 0.3A/W,and the highest spectral response is around *** cut-off frequencies are all over 108Hz.

关键词： silicon photodetector high responsibility PERL technique silvaco software

Analysis and Improvement of Automotive High Intensity Discharge Lamp Ballast Based on Microcontroller Unit

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Semiconductor Photonics and Technology 2008年第2期14卷 131-135页

作者： CUI Jia, WANG Jian-ming(school of information and communication Engineering, tianjin polytechnic university,{4., CHN) school of information and communication Engineering Tianjin Polytechnic University Tianjin 300160

The superior performance of high intensity discharge（HID） headlamp is clearly shown for luxury sedans, and the lamp luminescence properties are analyzed. The principle of its ballast technology is analyzed in detail. For against the disadvantage of current ballast technology for sedans lamp, a novel type of electronic ballast for HID is designed based on programmable intelligent computer（PIC） microcontroller unit（MCU） and S1A24.0M inverter and it provides guidance and can be easily used in control configuration selection and design. The feasibility and superiority of the system are proved.

关键词： HID igniter ballast transformer MCU

Study on Detection and Recognition of Speed Signs

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Semiconductor Photonics and Technology 2010年第Z1期 77-82页

作者： LIU Li,XIAO Zhitao,LV Jinpu(Department of information and communication,tianjin polytechnic{4.,tianjin 300160,CHN)

Speed sign detection and recognition are the important part of the driving assistant *** gradient-based random Hough transform with BP network,a method is proposed to detect and recognize speed ***,the gradient-based random Hough transform is used to detect and locate the speed *** four contour features of the ’digit’ inside the speed signs are extracted and recognized using the method of BP *** results show that this method can detect and recognize the speed signs accurately and efficiently.

关键词： speed signs random Hough transform BP network contour feature

Implementation of Dynamic System Control Circuit Board Test System of Pure Electric Vehicles

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Semiconductor Photonics and Technology 2010年第4期16卷 167-172页

作者： BI Wei, WANG Jianming, DOU Ruzhen, GAO Hua (Department of information and communication, tianjin polytechnic university, tianjin 300160, CHN) Department of information and communication Tianjin Polytechnic University Tianjin 300160

The dynamic system control circuit board(DSCCB)is one of the most important components for dynamic system of pure electric vehicles. The current detection of the DSCCB is done manually, which is not only inefficient in the detection but also difficult to guarantee the data accuracy. In order to improve the detection efficiency and accuracy, a new testing system is designed by Labview. The total test time can be further reduced by about 75% compared with the results of the manual detection. In this paper, the three-parameter sine wave curve-fit algorithm theory is applied to the phase delay detection of the current sensor sampling circuit on the DSCCB. This method solves the problem of big error in the phase delay detection.

关键词： pure electric vehicles automatic test system PXI platform three-parameter sine wave curve-fit algorithm

Wavelet Packet-based Feedback System for Medical Image Fusion

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Semiconductor Photonics and Technology 2010年第Z1期 102-108页

作者： YU Qiuyan1,HAN Xiaojun2(Department of information and communication,tianjin polytechnic{4.,tianjin 300160,CHN)

In order to meet the requirements of medical research,diagnosis and treatment,a new algorithm for image fusion based on the wavelet packet transform in conjunction with both subjective and objective assessments is put forward in the *** to the wavelet transform,the wavelet packet transform is more intricate and effective for the medical image *** indicated by the experimental results,parameters of the feedback system of the new algorithm are significantly superior to those of the wavelet transform,with practicability and accuracy.

关键词： medical image fusion wavelet packet subjective assessment feedback system

A STUDY PF THE COLLABORATIVE PRODUCT COMMERCE BASED ON THE ENTERPRISE FLEXIBILITY

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A STUDY PF THE COLLABORATIVE PRODUCT COMMERCE BASED ON THE E...

Efficient Wireless Digital Up Converters Design Using System Generator

2005年中国机械工程学会年会

作者： QI Qingzhu (school of Accounting, tianjin polytechnic university, tianjin, 300160)

＜正＞The fast development of the information technology has become the solid basis for increasing the enterprise flexibility and competition competence, while the single information system used on part of the enterprise branch has been proved to be a failure to the whole enterprise. Therefore, the collaborative product commerce （CPC） is brought forward. While now, the study on the whole enterprise flexibility is not enough and the study on CPC is mainly about the technology. So in this article, aiming at these shortages, we study on the CPC based on the enterprise flexibility. First, the article brings forward the concept of the CPC based on the enterprise flexibility. Then, combining to the meanings and the key-dimensions of the enterprise flexibility, we study the framework and basic characters of the CPC based on the enterprise flexibility. Finally, the article brings forward how to construct and implement CPC in detail.

关键词： enterprise flexibility collaborative product commerce system key-dimensions platform

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Efficient Wireless Digital Up Converters Design Using System...

Research on Electric Field Confinement Effect in Silicon LED Fabricated by Standard CMOS Technology

2008 9th International Conference on Signal Processing(ICSP’2008)

作者： Wang Wei Zeng Yifang Yan Yang school of information & communication Engineering tianjin{4. university tianjin City China 300160

A WCDMA Digital Up Converter（DUC） design based on FPGA is *** to shorten the design period and increase the design performance,a powerful design tool,Xilinx System Generator is *** RRC filter and the Half-band filter are designed by using MATLAB FDATool,and implemented by using Xilinx FIR *** DDS module is generated by Xilinx DDS ***,the DUC design is implemented into Xilinx XC5VSX50T *** Vitex-5 DSP4.E slices,the complex-multiplier speed reaches *** simulation results show that the system design flow based on Xilinx System Generator is simple and feasible,and the productivity is *** performance meets the requirements for the downlink transmit path.

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Semiconductor Photonics and Technology 2010年第Z1期 83-86+91页

作者： YANG Guanghua1,2,WANG Wei3(1.Electronic and information school,tianjin university,tianjin 300072,CHN 2.information and communication Inst.,tianjin polytechnic university,tianjin 300160,CHN 3.Institute of Semiconductors of Chinese Academy of Sciences,Beijing 100083,CHN)

The wedge-shaped and leaf-type silicon light-emitting devices(LED)are designed and fabricated with the Singapore Chartered Semi Inc.'s dual-gate standard 0.35μm CMOS *** basic structure of the two devices is N well-P+ junction.P+ area is the wedge-shaped structure,which is embedded in N *** leaf-type silicon LED device is a combination of the three wedge-shaped LED *** main difference between the two devices is their different electrode distribution,which is mainly in order to analyze the application of electric field confinement(EFC).The devices' micrographs were measured with the Olympus IC test *** forward and reverse bias electrical characteristics of the devices were *** measurements of the devices show that the electrode layout is very important when the electric field confinement is applied.

关键词： silicon LED standard CMOS technology electric field confinement effect