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Scattering of a partially coherent plane-wave pulse

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Scattering of a partially coherent plane-wave pulse

中国光学学会2011年学术大会

作者： Chaoliang Ding 1,Yangjian Cai 2,Yongtao Zhang 1,and Liuzhan Pan 1 1.Department of Physics,Luoyang Normal College,Luoyang 471022,china 2.school of Physical science and technology,Soochow university,Suzhou 215006,china

＜正＞In recent years the s tatistical properties of the light generated by scattering have b een studied extensively due to their considerable interest in medical diagnostics and imaging,remote sensing of the atmosph...

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Effect of RE-B-Al on Composition of Permeation Layer

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Journal of Rare Earths 2000年第1期18卷 45-45页

作者： JI Ze-sheng(school of Materials science and Engineering, Harbin university of science and technology, Harbin 150080, china)

It is indicated that the initial layer of RE-B-Al permeation is mainly composed of Fe2B by means of TEM and EDAX, and (RE0.65 Feo0.35) 23B6 is found after RE permeation for 4 h. (Fe0.8, RE0.2)6B is found in the layer of RE-B-Al permeation and the distance of crystal face of α-Fe is enlarged. The mechanism of formation of boride was analyzed. Prevention of compounds, such as Al, C etc., on dislocation movement, strengthening of grain boundary, dislocation and solution are responsible for the properties in the permeation layer.

关键词： rare earths B-Al permeation phase composition strengthening

Calculation and Test on the Actuator of a Micro-thermoacoustic Stifling Cooler

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Calculation and Test on the Actuator of a Micro-thermoacoust...

2008国际低温与制冷大会

作者： E Q~* Wu F~* Li D Y~* Guo F Z~(**) * school of science Wuhan Institute of technology Wuhan 430074 P.R.china ** Cryogenic Laboratory Huazhong university of science & technology Wuhan 430074 P.R. china

＜正＞A MEMS based cooler would allow integration of a cooling system directly into an electronic *** an electromagnetic micro-actuator used,a micro thermo-acoustic cooler can be *** diaphragms were proposed as the means to sweep the working gas in the Stirling cooler,replacing the pistons and displacers found in macro scale free-piston machines;and planar coils were used to drive the permalloy magnet diaphragm,thus sound power was provided. Micro-electromagnetic force between the planar coil and the permalloy magnet film was studied. Experiments on measuring the electromagnetic force constant of the planar coil-permalloy film have been performed.

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Multi-Path Acquiring Methods Based on Multi-Population Parallel Genetic Algorithm

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Multi-Path Acquiring Methods Based on Multi-Population Paral...

第二十七届中国控制会议

作者： Wang Zhengwu,Li Chunyuan school of Traffic & transportation Engineering,Changsha university of science & technology,Changsha,Hunan 410076,P.R.china

To avoid the negative effect of guidance and to decrease congestion shifting caused because the drivers choose the optimum path simultaneously,more reasonable paths should be recommended,but there is no quick and effective algorithm to seek the k-shortest *** algorithm,characterized by overall optimization and potential parallel,is suitable for k-shortest path *** the ordered nodes are applied,premature convergence and low searching efficiency at later stage of evolutionary often appear because a large number of invalid paths are produced during the genetic operation,and the path is more blindly *** paper will improve the algorithm in two ways:firstly,convergence speed is improved by the introduction of multi-population parallel algorithm which can maintain the population diversities,prevent premature con-vergence and improve later searching efficiency;secondly,a new code method is used to reduce algorithm *** code method based on the turn actions is adopted to decrease the invalid path number during the genetic operation while the loop punishment factor is introduced in the fitness calculation to avoid the operations of eliminating *** research shows that the improved algorithm has the advantages on fast convergence and high searching efficiency.

关键词： Multi-population parallel genetic algorithm K-shortest path algorithm Multi-route guidance Migration

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一种基于空间优化的彩色图像鲁棒水印算法

武汉理工大学学报 2010年第11期32卷 105-107页

作者：谭秀湖解梅黄友澎电子科技大学电子工程学院成都610054 武汉数字工程研究所武汉430074

针对彩色数字图像的版权保护问题,提出了一种基于空间优化的鲁棒性水印算法。算法将彩色图像由RGB转换到HIS(H为色度、I为亮度、S为饱和度)空间,选择饱和度S作为嵌入域并进行空间优化,将水印嵌入到最少受图像改变影响的子空间。通过对... 详细信息

针对彩色数字图像的版权保护问题,提出了一种基于空间优化的鲁棒性水印算法。算法将彩色图像由RGB转换到HIS(H为色度、I为亮度、S为饱和度)空间,选择饱和度S作为嵌入域并进行空间优化,将水印嵌入到最少受图像改变影响的子空间。通过对特征子空间选取限制,算法具有高的检测概率和安全性,低的虚警概率。仿真得到的结果,表明了算法具有好的鲁棒性。

关键词：彩色数字图像数字水印空间优化鲁棒性

钇基重稀土合金变质团球γ+(Fe,Mn)_3C共晶体增强奥氏体钢基自生复合材料

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中国稀土学报 2002年第Z2期20卷 145-147页

作者：梁高飞许振明姜启川李建国上海交通大学材料科学与工程学院上海200030 吉林大学材料学院吉林长春130025

采用Y基重稀土合金变质处理钢液,通过影响钢液中C,Mn等合金元素的偏析和相的生成,从而控制钢液凝固组织,在铸态下获得团球γ+(Fe,Mn)3C共晶体增强奥氏体钢基自生复合材料(AMGE)。Y基重稀土合金增大C,Mn元素的偏析,使凝固后期初生奥氏体... 详细信息

采用Y基重稀土合金变质处理钢液,通过影响钢液中C,Mn等合金元素的偏析和相的生成,从而控制钢液凝固组织,在铸态下获得团球γ+(Fe,Mn)3C共晶体增强奥氏体钢基自生复合材料(AMGE)。Y基重稀土合金增大C,Mn元素的偏析,使凝固后期初生奥氏体枝晶间小熔池中的成分达到共晶反应区,在非平衡凝固条件下生成γ+(Fe,Mn)3C共晶体。干摩擦磨损试验表明,在中、低载工况下AMGE的磨损量比基体合金奥氏体中锰钢低1～3倍,并且AMGE发生严重磨损时的载荷高于基体合金。

关键词：稀土团球共晶体自生复合材料 Y基重稀土耐磨性

Delay-dependent Exponential Stabilization of Nonlinear Delay Systems Subject to Impulsive Disturbance of Input

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Delay-dependent Exponential Stabilization of Nonlinear Delay...

第二十七届中国控制会议

作者： Jiang Haibo1,Zhou Caigen2,Yu Jianjiang2,Xu Chunming1 1.school of Mathematical sciences,Yancheng Teachers university,Yancheng 224051,P.R.china 2.school of Information science and technology,Yancheng Teachers university,Yancheng 224002,P.R.china

The problem of delay-dependent exponential stabilization of nonlinear delay systems subject to impulsive disturbance of input is investigated by employing Lyapunov *** nonlinear delay system is represented by the well-known T-S fuzzy *** so-called parallel distributed compensation（PDC） idea is employed to design the state feedback controller. Sufficient conditions,which are dependent of time delays,for global exponential stability of the closed-loop system are derived in terms of linear matrix inequalities（LMIs）,which can be easily solved by LMI *** results show the effectiveness of the proposed controller design methodology.

关键词： Nonlinear systems T-S fuzzy model Fuzzy control Linear matrix inequality (LMI) Global exponential stability

The studying of combined power-load forecasting by error evaluation standard based on RBF network and SVM method

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The studying of combined power-load forecasting by error eva...

2009中国控制与决策会议

作者： Zhiping Fan~(1,2),Zhong Qin~3,Tiansheng Hong~2,Yufei zhuang~1 1.College of Computer science & Educational Software,Guangzhou university,Guangzhou,Guangdong,510006,china 2.school of Engineering,South china Agricultural university,Guangzhou,Guangdong,510642,china 3.school of Civil Engineering,Guangzhou university,Guangzhou,Guangzhou,china,510006

＜正＞The load forecasting method usually starts from a single method,we usually improved prediction methods to get the better forecasting accuracy,but this often confined to the application of the method,combination forecasting method can achieve superiority of various methods,the forecast accuracy is higher than single forecasting *** this paper,we used RBF neural network prediction method and support vector machine forecasting *** neural network prediction method is the more popular method in recent years,it has the better generalization ability to the traditional neural network prediction method,It can effectively avoid local minima value and has a very good learning ability;S VM prediction method is transformed into one-dimensional nonlinear prediction of linear space,it has very precise calculation process and can meet the high forecast *** on the combination of the two methods,not only from the Angle of artificial memory model prediction,and using the tight nonlinear model,ultimately meet the purpose of combined *** main innovation in this paper is that assess the result of every kind of prediction method by making the standards of error qualified,using the error rate to determine the weight of combination,finally,we can get the satisfactory results through an empirical analysis.

关键词： Combined weight RBF network SVM method Power load

ADAPTIVE COPY AND DATA DISSEMINATION IN VEHICULAR AD-HOC NETWORKS

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ADAPTIVE COPY AND DATA DISSEMINATION IN VEHICULAR AD-HOC NET...

2009 IEEE International Conference on Communication technology and Applications（ICCTA2009）

作者： Jianwei Niu~1 Chang Liu~1 Canfeng Chen~2 Jian Ma~2 1school of Computer science and Engineering Beihang university Beijing 100191 china 2 Nokia Research Center Beijing 100176 china

＜正＞Vehicular ad-hoc networks（VANETs） are promising for more and more intelligent transportation applications,where information is disseminated over a group of *** are characterized for its unstable framework,in which the isolated vehicles communicate with others only when the unexpected meetings occur. As a result,some available data dissemination schemes do not work well in VANETs. In this paper,we propose an opportunistic auto-adaptive dissemination scheme-Adaptive Copy and Spread（ACS） Algorithm - for VANETs,which makes use of the moving patterns of vehicles like direction and velocity,and dynamically adjusts the dissemination *** scheme dynamically increases or decreases the number of message copies inside the broadcast area,and vehicles can intelligently decide when to start or stop broadcast a *** is designed to keep the message at the effective area’s boundary to inform the entering vehicles as soon as *** simulation results show that ACS enhance the data dissemination performance significantly with a smaller network load compared with random choice algorithm and Epidemic dissemination algorithm over a series of scenarios.

关键词： Adaptive Copy and Spread Vehicular Ad hoc Networks Opportunistic Networks Data Dissemination