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Main chemical ingredients of the celadon glaze from Qingliangsi kiln and Zhanggongxiang kiln

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Science china(Physics,Mechanics & Astronomy) 2006年第4期49卷 487-495页

作者： ZHAO Weijuan1, LU Xiaoke1, LI Guoxia1, GUO Min1, XIE Jianzhong1, GAO Zhengyao1, SUN Xinmin2, GUO Musen2, CHENG Huansheng3 & ZHANG Bin3 1. Faculty of Physical engineering, zhengzhou university, zhengzhou 450052, china 2. Research institute of Cultural Relic and Archaeology, Henan Province, zhengzhou 450004, china 3. Research institute of Modern Physics, Fudan university, Shanghai 200433, china Faculty of Physical engineering Zhengzhou University Zhengzhou China Research institute of Cultural Relic and Archaeology Zhengzhou China Research institute of Modern Physics Fudan University Shanghai China

The proton induced X-ray emission (PIXE) is used to determine the chemical ingredients of seven main elements in the samples of Ru Guan porcelain glazes and Ru Civil porcelain from Qingliangsi kiln in Baofeng County and the samples of celadon glaze from Zhanggongxiang kiln in Ruzhou City. The PIXE data are then analyzed by scatter analysis and fuzzy cluster method for determining their classification and provenance. The results show that there are obvious differences between the ingredients of glaze material of Ru Guan porcelain and Ru Civil porcelain from Qingliangsi kiln, of which the former ingredients are stable and its source is localized, and that the sources and ingredients of the glaze of Ru Guan porcelain and those of celadon glaze from Zhanggongxiang kiln are not wholly the same, of which the latter sources are much scattering.

关键词： Zhanggongxiang kiln, Qingliangsi kiln, the source of raw material, the proton induced X-ray emission.

F_p上一类△_p与Ω_p构造的全向置换的奇异性质

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通信学报 2004年第2期25卷 51-54页

作者：谢铁顿解放军信息工程大学电子技术学院河南郑州450004

证明了利用有限素域Fp上的循环移位拉丁方Dp和拉丁方Wp产生的全向置换必定是Fp加群上的完全映射,而且这类全向置换一定是F上的线性函数。

关键词：有限素域全向置换正交拉丁方完全映射线性函数

Improved performance of GaN-based light-emitting diodes by using short-period superlattice structures

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Progress in Natural Science:Materials International 2010年第1期20卷 70-75页

作者： Yi-jung LIU~1,Chien-chang HUANG~1,Tai-you CHEN~1,Chi-shiang HSU~1,Shiou-ying CHENG~2, Kun-wei LIN~3,Jian-kai LIOU~1,Wen-chau LIU~1 1.institute of Microelectronics,Department of Electrical engineering,National Cheng-Kung university, Tainan 70101,Taiwan,china 2.Department of electronic engineering,Nation Ilan university,I-Lan 26041,Taiwan,china 3.Department and Graduate institute of Computer Science and information engineering, Chaoyang university of technology,Taichung 41349,Taiwan,china institute of Microelectronics Department of Electrical Engineering National Cheng-Kung University Tainan 70101 Taiwan China Department of electronic engineering Nation Ilan University I-Lan 26041 Taiwan China Department and Graduate institute of Computer Science and information engineering Chaoyang University of Technology Taichung 41349 Taiwan China

An InGaN/GaN multiple-quantum-well（MQW）light-emitting diode（LED）with a ten-period i（undoped）-InGaN/p（Mg doped）-GaN（2.5 nm/5.0 nm）superlattice（SL）structure,was *** SL structure that can be regarded as a confinement layer of holes to enhance the hole injection efficiency is inserted between MQW and p-GaN *** studied LED device exhibits better current spreading performance and an improved quality,compared with a conventional one without SL *** to the reduced contact resistance as well as more uniformity of carriers injection,the operation voltage at 20 mA is decreased from 3.32 to 3.14 V.A remarkably reduced reverse-biased leakage current(10-7-10-9A)and higher endurance of the reverse current pulse are *** measured output power and external quantum efficiency（EQE）of the studied LED are 13.6 mW and 24.8%,respectively. In addition,significant enhancement of 25.4%in output power as well as increment of 5%in EQE for the studied devices is observed, as the studied devices show superior current spreading ability and reduction in dislocations offered by the SL structure.

关键词： GaN superlattice(SL) current spreading hole confinement electrostatic discharge(ESD)

A general communication performance evaluation model based on routing path decomposition

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Journal of Zhejiang university-Science C(Computers and electronics) 2011年第7期12卷 561-573页

作者： Ai-lian CHENG 1,Yun PAN 1,2,Xiao-lang YAN 2,Ruo-hong HUAN 3 (1 Department of information Science and electronic engineering,Zhejiang university,Hangzhou 310027,china) (2 institute of VLSI Design,Zhejiang university,Hangzhou 310027,china) (3 College of Computer Science and technology,Zhejiang university of technology,Hangzhou 310023,china) Department of information Science and electronic engineering Zhejiang University institute of VLSI Design Zhejiang University

The network-on-chip (NoC) architecture is a main factor affecting the system performance of complicated multi-processor systems-on-chips (MPSoCs).To evaluate the effects of the NoC architectures on communication efficiency,several kinds of techniques have been developed,including various simulators and analytical *** simulators are accurate but time consuming,especially in large space explorations of diverse network configurations;in contrast,the analytical models are fast and flexible,providing alternative methods for performance *** this paper,we propose a general analytical model to esti-mate the communication performance for arbitrary NoCs with wormhole routing and virtual channel flow *** resolve the inherent dependency of successive links occupied by one packet in wormhole routing,we propose the routing path decomposition approach to generating a series of ordered link *** we use the traditional queuing system to derive the fine-grained transmission latency for each network *** to our experiments,the proposed analytical model provides a good approximation of the average packet latency to the simulation results,and estimates the network throughput precisely under various NoC configurations and ***,the analytical model runs about 10 5 times faster than the cycle-accurate NoC *** applications of the model including bottleneck detection and virtual channel allocation are also presented.

关键词： Analytical model Communication performance Network-on-chip (NoC) Queuing system Routing path decom-position Virtual channel

Effect of rare earths on phase transformation in as-cast ZA27 alloy dur-ing compressive creep

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Rare Metals 2003年第4期22卷 259-264页

作者： WEIXiaowei SHENBaoluo DepamnentofAppliedPhysics UniversityofElectronicScienceandTechnologyofChinaChengdu610045China DeparlanentofMetalScience SichuanUniversityChengdu610065China

The effect of the mixed rare earths of Ce on the phase transformation in ascast ZA 27 alloy during compressive was investigated under 37 MPa and at 160 deg C by X-raydiffraction technique and SEM. The results showed that the as cast microstructure of ZA 27-RE alloyconsisted of a dendritic Al-rich alpha' surrounded by Zn-rich beta' phase, interdendritic epsilonphase and Zn-rich eta phase together with a complex Z phase which was a complex constitute compound,(RE,Cu)Al_5Zn_(16), dispersed in crystal interfaces or branch crystal interfaces and stable duringcompressive creep test at 160 deg C. The phase transformations of ZA 27-RE alloy, decomposition ofbeta' phase arid four transformation, were delayed by the addition of rare earths, also the lamellarstructure and the spheroidized structure in ZA 27-RE alloy were finer than in ZA 27 alloy duringcompressive creep test at 160 deg C at the same creep time, and the compressive creep resistance ofZA 27-RE alloy was higher than that of ZA 27 alloy.

关键词： microstructure change compressive creep rare earths ZA 27 alloy

Estimating fisheye camera parameters from homography

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Science china(information Sciences) 2012年第9期55卷 2119-2127页

作者： ZHU HaiJiang 1,YANG Ping 2 & LI ShiGang 3 1 School of information Science and technology,Beijing university of Chemical technology,Beijing,100029,china 2 National institute of Metrology,100013,Beijing,china 3 Department of Electrical and electronic engineering,Tottori university,680-8552,Koyama,Tottori,Japan School of information Science and technology Beijing University of Chemical Technology Beijing China National institute of Metrology Beijing China Department of Electrical and electronic engineering Tottori University Koyama Tottori Japan

This paper presents a method to linearly estimate fisheye camera model parameters from the homography induced by the space plane between two fisheye *** homography is firstly calculated by using four feature points,instead of three points on the same line,in the fisheye *** the constraint on the model parameters of fisheye camera can be derived from the homography under the assumption that fisheye camera model is a polynomial *** the model parameters for different order polynomials are *** proposed technique requires only multiple fisheye images to include a planar scene and need not a priori knowledge of 3D coordinate of the planar *** results with synthetic data and real fisheye images demonstrate the validity of our *** method can also be extended to fisheye image of other planar scene excluding the planar calibration object.

关键词： homography parameter estimation fisheye camera

THEORETICAL DESIGN AND MOTION PLANNING OF NONHOLONOMIC MANIPULATOR

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Chinese Journal of Mechanical engineering 2004年第2期17卷 222-225页

作者： Tan Yuegang Deng Yuhui WU Zhengping School of Mechanical and electronic engineering,Wuhan university of technology,Wuhan 430070, china Department of Science and technology Studies University College London WC1E 6BT UK School of Mechanical and electronic engineering Wuhan University of Technology Wuhan 430070 China

A new nonholonomic transmission mechanism is proposed based on thenonholonomic theory and nonlinear control principle, and combined with conditions of thenonholonomic motion planning and control, that is researched to compose method of the motiontransfer chain from this transmission mechanism, on which a new nonholonomic manipulator isdesigned. This nonholonomic manipulator is a controllable multi-joint manipulator that actuated onlyby two-servo electromotor. Its motion expresses the characteristic of nonholonomy constraint andnonlinear, and that also satisfies the chained form convertibility. And then, using the nonlinearcontrol principle of chained system, motion characteristic of the nonholonomic manipulator isapplied. From simulation verification and analysis, the usefulness of the theoretical design andcontrol strategies is shown, and that is important in design and research of handiness robot andmulti-finger robot hand.

关键词： Nonholonomic system Nonholonomic motion planning Nonlinear controlMulti-joint Manipulator

Repetitive learning control of nonlinear systems over finite intervals

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Science china(information Sciences) 2010年第1期53卷 115-128页

作者： SUN MingXuan1, WANG DanWei2 & CHEN PengNian3 1College of information engineering, Zhejiang university of technology, Hangzhou 310014, china 2School of Electrical and electronic engineering, Nanyang Technological university, Singapore 639794 3Department of Mathematics, china institute of Metrology, Hangzhou 310018, china College of information engineering Zhejiang University of Technology Hangzhou China School of Electrical and electronic engineering Nanyang Technological University Singapore Singapore Department of Mathematics China Institute of Metrology Hangzhou China

Iterative learning control requires initial repositioning, while the time functions to be learned should be of periodicity in repetitive control. However, there are cases in practice where the time-varying unknowns are not periodic but repetitive, and repetitive learning control is applicable with avoidance of initial repositioning. In this paper, repetitive learning control designs are presented for a broader class of nonlinear systems over finite intervals. The Freeman formula is modified and used for stabilization of the nominal nonlinear time-varying system undertaken. The global stability of the learning system and asymptotic convergence of the tracking error are established through analysis of both partially and fully saturated learning algorithms, respectively. The repetitive learning control method is theoretically shown to be effective in dealing with time-varying parametric uncertainties.

关键词： Initial condition problem convergence iterative learning control repetitive control repetitive learning control nonlinear systems

A SECURE PROXY SIGNATURE SCHEME BASED ON ELLIPTIC CURVE CRYPTOSYSTEM

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Journal of electronics(china) 2006年第1期23卷 54-57页

作者： Hu Bin Jin Chenhui electronic technology institute Information Engineering University Zhengzhou 450004 China

Proxy signature is a special digital signature which enables a proxy signer to sign messages on behalf of the original signer. This paper proposes a strongly secure proxy signature scheme and a secure multi-proxy signature scheme based on elliptic curve cryptosystem. Contrast with universal proxy signature schemes, they are secure against key substitute attack even if there is not a certificate authority in the system, and also secure against the original signer＇s forgery attack. Furtherlnore, based on the elliptic curve cryptosystem, they are more efficient and have smaller key size than other system. They can be used in electronics transaction and mobile agent environment.

关键词： Digital signature Proxy signature Multi-proxy signature Elliptic curve cryptosystem