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AN IMAGE RETRIEVAL METHOD BASED ON SPATIAL DISTRIBUTION OF COLOR

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Journal of electro.ics(China) 2006年第2期23卷 220-224页

作者： Niu Lei Ni Lin Miao Yuan dept of electro.ic eng. and lnfo. Science University of Sci. and Tech. of China Hefei 230026 China School of Computer Science and Mathematics Victoria University Australia

Color histogram is now widely used in image retrieval. Color histogram-based image retrieval methods are simple and efficient but without considering the spatial distribution information of the color. To overcome the shortcoming of conventional color histogram-based image retrieval methods, an image retrieval method based on Radon Transform (RT) is proposed. In order to reduce the computational complexity, wavelet decomposition is used to compress image data. Firstly, images are decomposed by Mallat algorithm. The low-frequency components are then projected by RT to generate the spatial color feature. Finally the moment feature matrices which are saved along with original images are obtained. Experimental results show that the RT based retrieval is more accurate and efficient than traditional color histogram-based method in case that there are obvious objects in images. Further more, RT based retrieval runs significantly faster than the traditional color histogram methods.

关键词： Content-Based Image Retrieval (CBIR) Radon transform Wavelet transform

REDUCING THE PEAK-TO-AVERAGE POWER RATIO OF OFDM SYSTEM WITH LOW COMPLEXITY

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Journal of electro.ics(China) 2006年第1期23卷 26-28页

作者： Luo Renze Jing Longjiang Luo Lang Li Jie Zhu Weile dept of electro. eng. Univ. of Electronic Science and Technology of China Chengdu 610054 China Zhongshan Institute Univ. of Electronic Science and Technology of China Zhongshan 528402 China

This paper proposes a companding scheme, where small signals are enlarged and large signals are reduced, to reduce the Peak-to-Average Power Ratio(PAPR). Computer simulation results show that the proposed technique has two advantages at least when compared with the conventional methods such as partial transmit sequence, selective mapping and the previous companding. First, it gets better PAPR performances with a lower complexity. Second, the scheme achieves greater performances gain with hardly any damnification of OFDM signals in some degree.

关键词： Orthogonal Frequency Division Multiplexing(OFDM) Peak-to-Average Power Ratio(PAPR) Compandor

A FAST SEAMLESS HANDOVER SCHEME AND ITS CDT OPTIMIZATION FOR PING-PONG TYPE OF MOVEMENT

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Journal of electro.ics(China) 2006年第2期23卷 298-303页

作者： Wang Yumlng Yang Zongkai Zhao Dasheng.He Jianhua Fu Xiaoming dept of electro. ＆ Info. eng. Huazhong Univ. of Sci. and Tech. Wuhan 430074 China Department of Electrical ＆ electro.ic eng.neering University of Bristol United Kingdom Institute for Informatics University of Goettingen 37083 Goettingen Germany

In mobile IPv6 networks, the ping-pong type of movement brings about frequent handovers and thus increases signaling burden. This letter proposes a fast seamless handover scheme where the access router keeps the mobile node's old reservation till the offline Count Down Timer (CDT) expires in order to reduce handover signaling and delay while the mobile node returns in a very short period of time. Based upon a pois son mobility model, an simple expression for CDT optimization is given out for the scheme to achieve the best cost performance of resource reservation.

关键词： Mobile IPv6 Ping-pong type of movement QoS signaling Handover delay Cost performance.

Application of Optical Coatings in Automotive Industry

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Semiconductor Photonics and Technology 2005年第3期11卷 196-202页

作者： DU Yuan-dong ZHONG Di-sheng dept. of Phys. Sci. ＆ electro.eng. Technol. Zhoukou Normal College Zhoukou 466000 CHN dept. of Phys. Liaoning University Shenyang 110036 CHN

From a production viewpoint , the optical thin films used to transparent substrates such as window glass for automobiles and the coating treatment process are reviewed. The state of the ar t of the technologies, and t... 详细信息

关键词： Optical coatings Water repellency Ultraviolet absorption Mechanical durability Deposition process

A SPEAKER ADAPTABLE VERY LOW BIT RATE SPEECH CODER BASED ON HMM

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Journal of Shanghai Jiaotong university(Science) 2000年第2期5卷 1-5页

作者：彭煳朱杰 dept.of electro.ic eng. Uuniv.of Electro-CommunicationsTokyo 182-8585Japan Shanghai Jiaotong Univ.and Bell Labs Joint Lab Shanghai 200030China

This paper presented a speaker adaptable very low bit rate speech coder based on HMM (Hidden Markov Model) which includes the dynamic features, i.e., delta and delta delta parameters of speech. The performance of this speech coder has been improved by using the dynamic features generated by an algorithm for speech parameter generation from HMM because the generated speech parameter vectors reflect not only the means of static and dynamic feature vectors but also the covariance of those. The encoder part is equivalent to an HMM based phoneme recognizer and transmits phoneme indexes, state durations, pitch information and speaker characteristics adaptation vectors to the decoder. The decoder receives those messages and concatenates phoneme HMM sequence according to the phoneme indexes. Then the decoder generates a sequence of mel cepstral coefficient vectors using HMM based speech parameter generation technique. Finally the decoder synthesizes speech by directly exciting the MLSA(Mel Log Spectrum Approximation) filter with the generated mel cepstral coefficient vectors, according to the pitch information.

关键词： mel cepstral coefficients hidden Markov model MLSA filter speaker adaptation Document code:A

Mechanism of Building-Up Deposited Layer during electro.Spark Deposition

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Journal of Surface eng.neered Materials and Advanced Technology 2012年第4期2卷 258-263页

作者： Amin D. Thamer Mohammed H. Hafiz Baha S. Mahdi Dean of Material eng.neering dept. Baghdad Iraq Lacturer in Production & Metallurgical eng. dept. Baghdad Iraq Prisedent of University of Tehchnology Baghdad Iraq

This paper studies the mechanism of formation of the deposit layer by (ESD) electro.spark deposition process. Inconel 738 substrates are coated with a deposited layer of NI6625 (Inconel 625). Selections of these two alloys have been done because they had wide applications and importance in the industry especially in gas turban blades in inland stations and in aircraft eng.nes. ESD is suggested because it has a low input heat process which eliminates the effect of HAZ in these Ni-superfluous due to their sustainability to micro-cracks. The coating contains many deposited sub-layers coming from evaporated and melted micro-regions as a result of locally high heat generated by discharging a series of capacitors charged and discharged in a controlled manner between electro.e and substrate material. The maximum deposition rates at the beginning of the process and decreases until been in a steady state condition due to the nature of the resultant morphology of the created surface.

关键词： ESD ESA electro.Spark Deposition IN738L Repairing NI6625 Surface Repairing of Gas Turbine Blades

Grid Connection of Doubly-Fed Induction Generators in Wind Energy Conversion System

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Grid Connection of Doubly-Fed Induction Generators in Wind E...

Robotic Unicycle Intelligent Robust Control Pt I: Soft Computational Intelligence Toolkit

CES/IEEE 5th International Power electro.ics and Motion Control Conference

作者： Ahmed G.Abo-Khalil Dong-Choon Lee Se-Hyun Lee dept.of Electrical.eng.Yeungnam Univ. 214-1DaedongGyeongsanGyeongbukKorea dept.of Electrical.eng.Yeungnam Univ. 214-1DaedongGyeongsanGyeongbukKorea electro.Mechanical Research Institute Hyundai Heavy Industry Co.LtdGyeongkiKorea

＜正＞This paper presents a new synchronization algorithm for grid connection of a doubly fed induction generator （DFIG） in wind generation system. A stator flux-oriented vector control is used for the variable speed DFIG operation. By controlling the generator excitation current the amplitude of the stator EMF is adjusted equal to the amplitude of the grid voltage. To set the generator frequency equal to the grid one, the turbine pitch angle controller accelerates the turbine/generator until it reaches the synchronous speed. A slight difference of stator and grid frequencies may cause the large phase difference between the two voltages. To compensate for this phase difference, a PLL algorithm is used. After the synchronization is achieved, the generator is connected to the grid and is controlled to extract the maximum power. The effectiveness of the proposed synchronization algorithm is verified by simulation results using PSCAD.

关键词： Wind energy synchronization DFIG PSCAD.

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Artificial Intelligence Advances 2020年第1期2卷 71-92页

作者： Ulyanov Sergey Ulyanov Viktor Yamafuji Kazuo Dubna State University Institute of system analysis and managementDubnaMoscow141980Russia INESYS LLC(EFKO GROUP) Ovchinnikovskaya naberezhnaya 20Bld 1Business Centre“Central City Tower”Moscow115035Russia NUST MISIS IYS Lab Leninskiy prospekt 4Moscow119049Russia dept.of Mechanical and Intelligent Control eng. University of Electro-Communications1-5-1 ChofuChofugaoka182 TokyoJapan

The concept of an intelligent control system for a complex nonlinear biomechanical system of an extension cableless robotic unicycle discussed.A thermodynamic approach to study optimal control processes in complex nonlinear dynamic systems *** results of stochastic simulation of a fuzzy intelligent control system for various types of external/internal excitations for a dynamic,globally unstable control object-extension cableless robotic unicycle based on Soft Computing(Computational Intelligence Toolkit-SCOptKBTM)technology presented.A new approach to design an intelligent control system based on the principle of the minimum entropy production(minimum of useful resource losses)determination in the movement of the control object and the control system is *** determination as a fitness function in the genetic algorithm is used to achieve robust control of a robotic *** algorithm for entropy production computing and representation of their relationship with the Lyapunov function(a measure of stochastic robust stability)described.

关键词： Robotics unicycle Intelligent control systems Essentially nonlinear model Globally unstable model Stochastic simulation Soft computing

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压电反平面裂纹问题中的电场梯度效应

华中科技大学学报（城市科学版） 2005年第B05期22卷 31-35页

作者：曾云胡元太 YANG Jiashi 华中科技大学土木工程与力学学院湖北武汉430074 dept. of eng. Mechanics Univ. of Nebraska

用含有电场梯度效应的电弹性体理论分析了压电体中的反平面裂纹问题.利用Fourier积分变换方法,将相应的复合边值问题转化为对偶积分方程组.求解这些方程组,获得了裂纹尖端的强度因子和能量释放率.通过与没有考虑电场梯度效应的经典理论... 详细信息

用含有电场梯度效应的电弹性体理论分析了压电体中的反平面裂纹问题.利用Fourier积分变换方法,将相应的复合边值问题转化为对偶积分方程组.求解这些方程组,获得了裂纹尖端的强度因子和能量释放率.通过与没有考虑电场梯度效应的经典理论中的结果相比较,发现电场梯度效应对裂纹尖端的强度因子和能量释放率有非常重要的影响.

关键词：压电反平面裂纹电场梯度强度因子能量释放率