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Efficient DPCA SAR imaging with fast iterative spectrum reconstruction method

Science china(Information Sciences) 2012年第8期55卷 1838-1851页

作者： FANG Jian1,ZENG JinShan1,XU ZongBen1&ZHAO Yao2.1M inistry of Education Key Lab for Intelligent networks and network Security Xi'an Jiaotong {2.,Xi'an 710049,china 2. ational Key Laboratory of Science and technology on Microwave Imaging&institute of Electronics,Chinese Academy of Sciences,Beijing 100049,china 1. Ministry of Education Key Lab for Intelligent networks and network Security Xi’an Jiaotong {2. Xi’an 710049 China2. National Key Laboratory of Science and Technology on Microwave Imaging & Institute of Electronics Chinese Academy of Sciences Beijing 100049 China

The displaced phase center antenna(DPCA)technique is an effective strategy to achieve wide-swath synthetic aperture radar(SAR)imaging with high azimuth ***,traditionally,it requires strict limitation of the pulse repetition frequency(PRF)to avoid non-uniform ***,any deviation could bring serious ambiguity if the data are directly processed using a matched *** break this limitation,a recently proposed spectrum reconstruction method is capable of recovering the true spectrum from the nonuniform ***,the performance is sensitive to the selection of the *** regularization based imaging may provide a way to overcome this *** existing time-domain method,however,requires a large-scale observation matrix to be built,which brings a high computational *** this paper,we propose a frequency domain method,called the iterative spectrum reconstruction method,through integration of the sparse regularization technique with spectrum analysis of the DPCA *** approximately expressing the observation in the frequency domain,which is realized via a series of decoupled linear operations,the method performs SAR imaging which is then not directly based on the observation matrix,which reduces the computational cost from O(N2.to O(N log N)(where N is the number of range cells),and is therefore more efficient than the time domain *** sparse regularization scheme,realized via a fast thresholding iteration,has been adopted in this method,which brings the robustness of the imaging process to the PRF *** provide a series of simulations and ground based experiments to demonstrate the high efficiency and robustness of the *** simulations show that the new method is almost as fast as the traditional mono-channel algorithm,and works well almost independently of the PRF ***,the suggested method can be accepted as a practical and efficient wide-swath SAR imaging technique.

关键词： displaced phase center antenna sparse regularization iterative thresholding spectrum reconstruction

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金属锰氮化的动力学研究

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铁合金 2004年第3期35卷 9-12页

作者：张金柱徐楚韶赵跃萍重庆大学材料科学与工程学院重庆中国400044 贵州工业大学材料与冶金工程学院贵阳中国550003

应用真空电阻炉高温渗氮、X射线衍射、惰气熔融法氧氮分析等实验测试方法,研究了金属锰在1143K含氮气氛中氮化的动力学规律。氮化试样的相组成一般为Mn4N和α-Mn,随渗氮时间的延长,金属锰可全部氮化为Mn4N和ζ-(Mn2.)。氮原子通过氮化... 详细信息

应用真空电阻炉高温渗氮、X射线衍射、惰气熔融法氧氮分析等实验测试方法,研究了金属锰在1143K含氮气氛中氮化的动力学规律。氮化试样的相组成一般为Mn4N和α-Mn,随渗氮时间的延长,金属锰可全部氮化为Mn4N和ζ-(Mn2.)。氮原子通过氮化产物层ζ相的扩散过程是金属锰氮化的主要控制环节。金属锰的转化率和反应时间的关系可表示为:1-3(1-X)2.3+2.1-X)=Kt。

关键词：金属锰渗氮动力学氮化锰真空电阻炉 X射线衍射

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An ant colony algorithm for solving Max-cut problem

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Progress in Natural Science:Materials International 2008年第9期18卷 1173-1178页

作者： Lin Gaoa,, Yan Zeng b, Anguo Dong a,c a School of Computer Science and technology, Xidian university, Xi’an 710071,{2. b Computer Science Department, Xi’an institute of Post & Telecommunications, Xi’an 710061,{2. c School of Science, Chang’an university, Xi’an 710064,{2. School of Computer Science and technology Xidian University Xi’an 710071 China Computer Science Department Xi’an Institute of Post & Telecommunications Xi’an 710061 China School of Science Chang’an University Xi’an 710064 China

Max-cut problem is an NP-complete and classical combinatorial optimization problem that has a wide range of applications in dif-ferent domains, such as bioinformatics, network optimization, statistical physics, and very large scale integration *** this paper we investigate the capabilities of the ant colony optimization (ACO) heuristic for solving the Max-cut problem and present an AntCut algo-rithm.A large number of simulation experiments show that the algorithm can solve the Max-cut problem more eficiently and efiectively.

关键词： Ant colony optimization Max-cut problem Algorithm

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Estimation of convergence rate for multi-regression learning algorithm

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Science china(Information Sciences) 2012年第3期55卷 701-713页

作者： XU ZongBen1,2. ZHANG YongQuan3,1,2.& CAO FeiLong3 1institute for Information and System Sciences, Xi’an Jiaotong university, Xi’an 710049,{2. 2.OE Key Labratory for Intelligent networks and network Security, Xi’an Jiaotong university, Xi’an 710049,{2. 3Department of Information and Mathematics Sciences,{2. Jiliang university, Hangzhou 310018,{2. 1. institute for Information and System Sciences Xi’an Jiaotong University Xi’an 710049 China2. MOE Key Labratory for Intelligent Networks and Network Security Xi’an Jiaotong University Xi’an 710049 China3. Department of Information and Mathematics Sciences China Jiliang University Hangzhou 310018 China

In many applications, the pre-information on regression function is always unknown. Therefore, it is necessary to learn regression function by means of some valid tools. In this paper we investigate the regression problem in learning theory, i.e., convergence rate of regression learning algorithm with least square schemes in multi-dimensional polynomial space. Our main aim is to analyze the generalization error for multi-regression problems in learning theory. By using the famous Jackson operators in approximation theory, covering number, entropy number and relative probability inequalities, we obtain the estimates of upper and lower bounds for the convergence rate of learning algorithm. In particular, it is shown that for multi-variable smooth regression functions, the estimates are able to achieve almost optimal rate of convergence except for a logarithmic factor. Our results are significant for the research of convergence, stability and complexity of regression learning algorithm.

关键词： learning theory covering number rate of convergence entropy number

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Differentiation transforming system

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Progress in Natural Science:Materials International 2009年第3期19卷 397-406页

作者： Qiang Chenga,b,c,*, Haibin Zhang d, Bin Wanga, Yonghua Zhao c a LASG, institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 10002., PR china b LSEC, institute of Computing Mathematics, Chinese Academy of Sciences, Beijing 100080, PR china c SC, institute of Computer network Information Center, Chinese Academy of Sciences, Beijing 100190, PR china d College of Applied Sciences, Beijing university of technology, Beijing 10012., PR china [a]LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 PR China [b]LSEC Institute of Computing Mathematics Chinese Academy of Sciences Beijing 100080 PR China [c]SC Institute of Computer Network Information Center Chinese Academy of Sciences Beijing 100190 PR China [d]College of Applied Sciences Beijing University of Technology Beijing 100124 PR China

The differentiation transforming (DFT) system is developed to produce the tangent linear codes, which is used to calculate the Jaco- bian- and the Hessian-vector products with no truncation errors. This paper first gives the introduction of the functionality and features of the DFT system, and then discusses several techniques for the implementation of automatic differentiation tools, including data depen- dence analysis, singular differentiation and code optimization. Finally, the codes generated with DFT used in several applications have been demonstrated.

关键词： Jacobian Hessian Tangent linear model Automatic differentiation

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黔东早-中寒武世凯里组疑源类组合及其界线意义

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微体古生物学报 2001年第1期18卷 55-69页

作者：杨瑞东尹磊明贵州工业大学资源与环境学院贵阳550003 中国科学院南京地质古生物研究所南京210008

通过对台江八郎和丹寨平寨两条剖面凯里组中疑源类化石的分析、研究 ,台江剖面产疑源类化石有 17属 35种 (12.定种 ) ,其中以 L eiosphaeridia,Synsphaeridium,Cymatiosphaera,Pterospermella最为丰富 ;可划分为 3个组合 ,即 Cymatiosp... 详细信息

通过对台江八郎和丹寨平寨两条剖面凯里组中疑源类化石的分析、研究 ,台江剖面产疑源类化石有 17属 35种 (12.定种 ) ,其中以 L eiosphaeridia,Synsphaeridium,Cymatiosphaera,Pterospermella最为丰富 ;可划分为 3个组合 ,即 Cymatiosphaera ***- Fimbriaglomerella membrancea组合 ,Cristallinium- Micrhystridium - Pterosper-mella组合和 Dictyotidium- Granomarginata组合。丹寨平寨剖面凯里组所产疑源类化石有 :13属 2.1种 (5未定种 ) ,同样划分为 3个组合 ,即 L eiosphaeridia- Tasmanites组合 ,Retisphaeridium- Micrhystridium tentatium组合和Baltisphaeridium - Bubomorpha hunjiangensis组合。本文对两条剖面中的疑源类化石的组成、相对含量做了详细的统计 ,发现在八郎剖面 9- 2.和平寨剖面 3层疑源类的丰度、分异度开始发生明显的变化 ,表现由早寒武世向中寒武世疑源类组合面貌的转变 ,这一疑源类转变层位正好是与三叶虫划分的中、下寒武统界线的层位位置相一致。这充分表明疑源类化石可作为划分中。

关键词：疑源类组合凯里组贵州早-中寒武世

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Research advances in the Mesozoic tectonic regimes during the formation of Jiaodong ore cluster area

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Progress in Natural Science:Materials International 2006年第8期16卷 777-784页

作者： DENG Jun, YANG Liqiang, GE Liangsheng, WANG Qingfei, ZHANG Jing, GAO Bangfei, ZHOU Yinghua and JIANG Shaoqing (State Key Laboratory of Geological Processes and Mineral Resources, china university of Geosciences, Beijing 100083, china Key Laboratory of Lithosphere Tectonics and Lithoprobing technology of Ministry of Education, china university of Geosciences, Beijing 100083, china) [a]State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing China [b]Key Laboratory of Lithosphere Tectonics and Lithoprobing technology of Ministry of Education China University of Geosciences Beijing China

Based on research advances of the tectonic regime in Jiaodong ore cluster area and the related tectonic regime transformation in Mesozoic era in the eastern region of North china, in this paper, we first summarize some key problems required to be studied further on. Then we suggest an approach to dealing with these problems. It is known that the gold deposits in Jiaodong ore cluster area, which are of different mineralization styles, spatial distributions and geological settings, might be as a result from one or more geologic events in Mesozoic. Till now, this kind of research on the temporal evolution and spatial migration sequence, especially on the geodynamic mechanism of the above events, is far from sufficient. Moreover, quantitatively describing the action mode and the temporal-spatial framework of tectonic dynamic regimes and formulating the relative contribution of every tectonic dynamic regime for the metallogensis are still challenges to the geologists studying on the formation of Jiaodong ore cluster area. According to the interpretation of the regional tectonic analysis, the structural dynamics, the observation and the exploration of the mineralization network, we propose a geological-physical-chemical model with some constraints originated from the comprehensive analysis. We then use this model to simulate the coupled processes of the structural deformation, thermal transport, fluid flow and the chemical reaction. The obtained results indicate that the model is efficient in further analyzing the temporal-spatial evolutional trail of the tectonic regime in Jiaodong ore cluster area and in further understanding the nature of the mass metallogensis.

关键词： tectonic regime Mesozoic era Jiaodong ore cluster area genesis metallogenic system.

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贵州凯里生物群中软舌螺的初步研究

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微体古生物学报 2003年第3期20卷 296-302页

作者：陈笑媛赵元龙王萍丽贵州工业大学资源与环境学院贵阳550003

本文描述了采自贵州台江县革东镇八郎中寒武世凯里生物群中的软舌螺化石 ,计有 1种 ,3相似种和 1个未定种。即 :Ambrolinevitus ***,Glossolites?sp.,H aplophrentis?***,L inevitus opimus,Hy-olithes?***。凯里生物群中软舌螺特点是 ... 详细信息

本文描述了采自贵州台江县革东镇八郎中寒武世凯里生物群中的软舌螺化石 ,计有 1种 ,3相似种和 1个未定种。即 :Ambrolinevitus ***,Glossolites?sp.,H aplophrentis?***,L inevitus opimus,Hy-olithes?***。凯里生物群中软舌螺特点是 :1)壳体通常较大 ,呈宽锥形 ;2.)背、腹壳区分明显 ,常具中槽或中脊 ;3)特别是以软舌螺目中的软舌螺科和线带螺科的软舌螺保存数量最多。完全与欧洲、北美相当层位中出现的软舌螺组合面貌相似 ;并与澄江动物群中的软舌螺在演化特征上是可衔接的。凯里生物群中的软舌螺除具有世界性属种外 ,还具地区特有的属种。这对研究软舌螺的地理分布、演化进程以及与凯里生物群组合关系有重要意义。

关键词：软舌螺凯里生物群中寒武世贵州地理分布化石

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A Dynamic Clustering Routing Algorithm Based on Support Degree for Wireless Sensor networks

A Dynamic Clustering Routing Algorithm Based on Support Degr...

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2.09 IEEE International Conference on Intelligent Computing and Intelligent Systems(ICIS2.09)

作者： Jing Yang 1 2.Baoguo Xu 1 Lu Hong 3 Zhuqing Jiao 1 1 Schoolof Communication and Control Engineering Jiangnan university Wuxi china 2.Electrical Engineering College {2. university guiyang china 3 Department of Electronic Engineering Huaihai institute of technology Lianyungang china

For monitoring burst events in a kind of reactive wireless sensor networks （WSNs）,a novel scheme of dynamic clustering routing algorithm （DCRA） based on support degree is *** new approach lets sensors decide whether become a clusterhead （CH） according to the support degree coming from *** traditional distributed clustering algorithms,DCRA combines energy,load balancing and topology information together by defining an objective function based on support ***,the clusterhead aggregates data and transmits the result to base station （sink node） along multiple *** new algorithm is completely distributed and *** results show that DCRA has great potential in efficiently distributing energy consumption and extending the network lifetime.

关键词： wireless sensor networks (WSNs) clustering support degree routing network lifetime

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Effective solutions to a global 3D visual system in networking environments

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Science china Earth Sciences 2005年第11期48卷 2032-2039页

作者： ZHANG Liqiang1,2. ZHANG Yan3, YANG Chongjun2. LIU Suhong1, REN Yingchao2. RUI Xiaoping2.& LIU Donglin2.1. State Key Laboratory of Remote Sensing Sciences, School of Geography and Remote Sensing, Beijing Normal university, Beijing 100875, china 2. State Key Laboratory of Remote Sensing Sciences, {2. of Remote Sensing Applications, Chinese Academy of Sciences, Beijing 101001, china 3. {2. of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 101001, china 1. State Key Laboratory of Remote Sensing Sciences School of Geography and Remote Sensing Beijing Normal University 100875 Beijing China 2. Chinese Academy of Sciences State Key Laboratory of Remote Sensing SciencesInstitute of Remote Sensing Applications 101001 Beijing China 3. institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences 101001 Beijing China

The development of Web-based global 3D visual system has made progresses. However, there exist few mature and effective ways for managing, transmitting and visualizing massive spatial data. Based on the related work, the paper illustrates the ellipsoidal quadtree technique for rapid access multi-scale and multiple level geographical data, integrates the streaming with level-of-detail rendering method for transmitting the data on the network, and im-plements large-scale terrain surface simplification using M-band wavelet transforms and mul-tiresolution triangulations. We fulfil a web-based global terrain visual system using COM com-ponents on the basis of the above techniques. The system has a good prospect in the military simulation and city plans.

关键词： massive spatial data, streaming transmission, system architecture, M-band wavelet

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