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Neuromorphic Continuous-Time State Space Pole Placement Adaptive Control

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Journal of Systems Engineering and Electronics 2003年第1期14卷 58-62页

作者： Lu Zhao & Sun MingweiDepartment of Electrical and Computer Engineering university of Houston, Houston, U.S. A The Third academy, china Aerospace Science and Industry Corporation, beijing 100074, P. R. china Department of Electrical and Computer Engineering university of Houston U. S. A The Third academy China Aerospace Science and Industry Corporation Beijing 100074 P. R. China

A neuromorphic continuous-time state space pole assignment adaptive controller is proposed, which is particularlyappropriate for controlling a large-scale time-variant state-space model due to the parallely distributed nature ofneurocomputing. In our approach, Hopfield neural network is exploited to identify the parameters of a continuous-timestate-space model, and a dedicated recurrent neural network is designed to compute pole placement feedback control law inreal time. Thus the identification and the control computation are incorporated in the closed-loop, adaptive, real-timecontrol system. The merit of this approach is that the neural networks converge to their solutions very quickly andsimultaneously.

关键词： Pole assignment Parameter identification Hopfield neural network Sylvester's equation Recurrent neural network.

Influence of “Holiday Tourism Circle of beijing” on Chengde Tourism Spatial Alteration and Reconstruction

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chinese Journal of Population,Resources and Environment 2006年第4期4卷 38-42页

作者： Li Chen1,2,Cheng Shengkui2,Chen Yuansheng2,Zhang Yingqiu1 1.College of Arts&Science,beijing Union university,beijing 100083,china 2.Institute of Geographical Science and Natural Resources Research,CAS,beijing 100101,china College of Arts & Science Beijing Union University Beijing 100083 China Institute of Geographical Science and Natural Resources Research CAS Beijing 100101 China Institute of Geographical Science and Natural Resources Research CAS Beijing 100101 China Institute of Geographical Science and Natural Resources Research CAS Beijing 100101 China College of Arts & Science Beijing Union University Beijing 100083 China

Chengde City,famous for its cultural sightseeing tourism industry,and is located in china's"Capital Holiday Tourism Circle".This location is advantageous,because of the recent boom in china's national tourism *** industry has gone through several structural and development changes with in the past several years.A result of these restructuring patterns is the great changes concerning competitive and cooperative relations among tourism destinations,which have precipitated the decline of the traditional sightseeing pattern. Northern china's"Capital Holiday Tourism Circle"is one of nine key areas within the chinese tourism industry under development during the Eleventh Five-Year *** the present article the method of"Distance Decline of The Tourist Flow"was used to define the flow of tourists in the Capital Holiday Tourism Circle and its influence upon Chengde's tourism spatial distribution.3 aspects will be discussed:(1)The transformation from sightseeing to leisure markets makes the change possible in Chengde's tourism spatial pattern.(2)The location advantage(adjacent to beijing and Tianjin) also leads to the change in Chengde tourism spatial pattern.(3)The establishment of freeways also contributes to a great degrees of change. The rapid development of leisure tourism might lead to the change from nucleus model to a diversified one within Chengde's ***,Chengde is developing the tourism industry with the central heritage area as the nucleus and the northern forest, pasture,southern mountain,and rivers as its periphery.

关键词： china Capital Holiday Tourism Circle Chengde city tourism space

Zircon SHRIMP U-Pb Dating and Neoproterozoic Metamorphism of Kangding and Yuanmou Intrusive Complexes,Sichuan and Yunnan

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Journal of Earth Science 2009年第6期20卷 897-908页

作者：李大鹏陈岳龙罗照华赵俊香 School of the Earth sciences and Resources China University of Geosciences Institute of Crustal Dynamics China Earthquake Administration

To clarify the relationship of the metamorphic intrusions along the west margin of the Yangtze craton and their metamorphic history after crystallization, the petrochemical and trace element geochemical characters, zircon SHRIMP U-Pb dating, and the chemical compositions of coexisting hornblendes and plagioclases from Neoproterozoic metamorphic intrusions in Kangding （康定）, Sichuan （四川） Province, and Yuanmou （元谋）, Yunnan （云南） Province, were studied. Combined with the former published data, it is indicated that the Kangding granitic plutons and Yuanmou complex in the west margin of the Yangtze craton generally formed at the same period. Metamorphic event at ~700 Ma existed extensively, at least covering from Kangding area in Sichuan to the Eshan （峨山） area in Central Yunnan. Moreover, amphibolite facies may represent the peak regional metamorphic condition.

关键词： Yangtze craton Kangding-Yuanmou complex SHRIMP metamorphic history.

Kinetics of Nitrogen Removal from Molten Steel under Vacuum and Gas-Blowing Conditions

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International Journal of Minerals,Metallurgy and Materials 1998年第1期12卷 5-8页

作者： Jie Fu Heming Chang Shixiang Zhou Boping Chen (Metallurgy Engineering School, university of Science and Technology beijing, beijing 100083, china) Metallurgy Engineering School University of Science and Technology Beijing Beijing 100083 China

The kinetics of nitrogen removal from molten steel under vacuum and gas-blowing conditions has beenstudied during the VIM process. The experimental results indicated that vacuum affected the kinetics of nitrogenremoval in the range of 67-5 360 Pa. At 67 Pa, the rate of nitrogen removal is controlled by the liquid phase masstransfer of nitrogen in molten steel. At 2 680Pa, the limited step for nitrogen removal from molten steel is the chemical reaction at the metal/gas interface. Under the present experimental conditions, the type (Ar, CO, CO2) and quantity of gas flowed have no evident influences on the rate of nitrogen removal. The ratio of nitrogen removal of gasbubbles is less than 3 %. Based on the experimental results, the mechanism of nitrogen removal during the VDprocess with argon blowing and the other melting or secondary refining processes with carbon-oxygen reaction havebeen discussed. Some new viewpoints are proposed.

关键词： kinetics nitrogen removal vacuum gas-blowing

Detection of CD2 expression in chicken hematogenic embryo yolk sac lymphoid cells prior to thymus genesis

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Progress in Natural Science:Materials International 2008年第12期18卷 1589-1594页

作者： Dongyu Zhou~a Jigui Wang~b Weiquan Liu~b Rongxiu Liu~c Yuehu Pei~a a College of Traditional chinese Materia Medica,Shenyang Pharmaceutical university,Shenyang 110016,china b College of Biological sciences,china Agricultural university,beijing 100094,china c Liaoning Tianhe Biotechnology Co.Ltd,Room 1203,100-1 Dongbinhe Road,Shenyang District,Shenyang 110016,china [a]College of Traditional chinese Materia Medica Shenyang Pharmaceutical University Shenyang 110016 China [b]College of Biological sciences China Agricultural University Beijing 100094 China [c]Liaoning Tianhe Biotechnology Co. Ltd Room 1203 100-1 Dongbinhe Road Shenyang District Shenyang 110016 China

Lymphoid mononuclear cells from chick embryos at stage 16 were collected prior to fetal liver and thymus genesis to study the dif- ferentiation and function of the hematogenic yolk sac and to detect whether CD2 occurs on the surface of lymphoid mononuclear cells. The phenotype and functional activity of the cell surface protein E receptor and the ultrastructure of embryonic E~+ cells were compared with those of mature T *** results indicate 99.36% homology between the E receptors of embryonic lymphocytes and mature T *** similarities,including molecular distribution,motivation,the ability to form an erythrocyte rosette,the structure of the receptor-ligand complex,and the conformation of the signal channel,were detected between embryonic lymphocytes and mature CD2-expressing T *** results indicate that CD2 is already expressed prior to fetal liver and thymus genesis and that its expression is not dependent on the thymic microenvironment.

关键词： CD2 Chicken embryo Hematogenic yolk sac

A STUDY ON THE FLOW BEHAVIOR OF AN AXISYMMETRIC LAMINAR JET

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Journal of Hydrodynamics 1993年第3期5卷 112-115页

作者： Chen Yuan Supervisor Prof.Lin Tong-ji,E Xue-quan Institute of Mechanics,chinese academy of sciences,beijing 100080,P.R.china

It is of great practical and theoretical importance to study the properties and flow behavior of laminar jet,because it tightly links the physical phenomena of nonlinerity such as flow stability and transition and so ***,many problems and differences exist in ba- sic concepts and in understanding of stable and transitional properties and flow patterns of ax- isymmetric laminar ***,a further study on this subject is needed to evaluate the exist- ing understandings and to find out the mechanism governing the behavior of actual axisymmetric laminar jet flow. In this thesis,the flow behavior of axisymmetric laminar jet issuing from nozzles of several diameters in the direction of gravity was studied experimentally using flow visualization tech- nique in the range of Reynolds number from tens to *** unstable and transitional processes in the laminar jet were *** influence on the jet flow of different geometry contours of jet chamber boundary was *** new flow phenomena were discovered which gave deeper understanding of flow patterns and their dependent factors in low Reynolds number axisymmetric laminar jet.A theoretical model to describe the variation of the axisym- metric laminar jet length influenced by the weak density difference is proposed based on the ex- perimental observation,which will be helpful in recognizing the flow behavior of axisymmetric laminar jet of low Reynolds numbers.

关键词： axisymmetric laminar jet jet stability flow visualization

An improved reduced-rank STAP interference suppression method in design of GNSS receivers

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Science china(Information sciences) 2012年第10期55卷 2329-2342页

作者： GONG WenFei & SUN Xin School of Electronics and Information Engineering,beijing Jiaotong university,beijing 100044,china 1. School of Electronics and Information Engineering Beijing Jiaotong University Beijing 100044 China

In this paper,we address the problem of interference cancellation in global positioning system(GPS) receiver using an adaptive reduced-rank space-time adaptive processing(STAP) interference suppression method based on multistage nested Wiener filter(MSNWF).This improved adaptive reduced-rank method is based on the improved Gerschgorin radii ***,the cross-correlations between the desired signals of the adjacent stages of MSNWF are directly used to calculate the Gerschgorin radii instead of employing the eigenvalue decomposition of the covariance ***,a heuristic decision rule based on Gerschgorin disk estimator(GDE) is employed to estimate the rank of interference *** optimal rank can be adaptively selected without increasing the *** and results of the experiment show that the proposed method further reduces the computation of STAP and enhances its real-time property with the interference suppression performance unaffected.

关键词： global positioning system reduced-rank space-time adaptive processing multistage nested Wiener filter Gerschgorin disk estimator

Perception of prosodic structure of chinese sentence

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chinese Journal of Acoustics 1997年第3期16卷 236-249页

作者： YANG Yufang (Institute of Psychology, chinese academy of sciences beijing 100012)

The perceptual representation of the prosodic structure of chinese sentences was constructed statistically by using the method of multidimensional scaling analysis on the basis of the result of a discrimination experiment, in which listeners were asked to compare perceptual distances between two adjacent syllables in each of six sentences. Listeners' ability to resolve levels of prosodic hierarchy and the relationship between the prosodic and syntactic structures were discussed in relation to perceptual representations.

关键词： Perception of prosodic structure of chinese sentence MDS

An eSnake model for medical image segmentation

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Progress in Natural Science:Materials International 2005年第5期15卷 424-429页

作者： Lv Hongyu1, YUAN Kehong2, BAO Shanglian1, ZU Donglin1 and DUAN Chaijie1*(1. The Research Center for Tumor Diagnosis and Therapeutical Physics & beijing Key Laboratory of Medical Physics and Engineering, beijing 100871, china 2. Key Laboratory of Pure and Applied Mathematics, School of Mathematical sciences, Peking university, beijing 100871, china) The Research Center for Tumor Diagnosis and Therapeutical Physics & beijing Key Laboratory of Medical Physics and Engineering Beijing 100871 China Key Laboratory of Pure and Applied Mathematics School of Mathematical Sciences Peking University Beijing 100871 China

A novel scheme of external force for detecting the object boundary of medical image based on Snakes (active contours) is introduced in the paper. In our new method, an electrostatic field on a template plane above the original image plane is designed to form the map of the external force. Compared with the method of Gradient Vector Flow (GVF), our approach has clear physical meanings. It has stronger ability to conform to boundary concavities, is simple to implement, and reliable for shape segmenting. Additionally, our method has larger capture range for the external force and is useful for medical image preprocessing in various applications. Finally, by adding the balloon force to the electrostatic field model, our Snake is able to represent long tube-like shapes or shapes with significant protrusions or bifurcations, and it has the specialty to prevent Snake leaking from large gaps on image edge by using a two-stage segmentation technique introduced in this paper. The test of our models proves that our methods are robust, precise in medical image segmentation.

关键词： image segmentation eSnake external force electrostatic field balloon force.