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A distributed computational cognitive model for object recognition

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Science China(Information Sciences) 2013年第12期56卷 5-17页

作者： liu yongjin FU QiuFang liu Ye FU XiaoLan Tsinghua National Laboratory for Information Science and Technology Department of Computer Science and Technology Tsinghua University State Key Lab of Brain and Cognitive Science Institute of Psychology Chinese Academy of Sciences

Based on cognitive functionalities in human vision processing, we propose a computational cognitive model for object recognition with detailed algorithmic descriptions. The contribution of this paper is of two folds. Firstly, we present a systematic review on psychological and neurophysiological studies, which provide collective evidence for a distributed representation of 3D objects in the human brain. Secondly, we present a computational model which simulates the distributed mechanism of object vision pathway. Experimental results show that the presented computational cognitive model outperforms five representative 3D object recognition algorithms in computer science research.

关键词： distributed cognition computational model object recognition human vision system

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Cognitive mechanism related to line drawings and its applications in intelligent process of visual media： a survey

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Frontiers of Computer Science 2016年第2期10卷 216-232页

作者： yongjin liu Minjing YU Qiufang FU Wenfeng CHEN Ye liu Lexing XIE Tsinghua National Laboratory for Information Science and Technology Department of Computer Science and Technology Tsinghua University Beijing 100084 China State Key Laboratory of Brain and Cognitive Science Institute of Psychology Chinese Academy of Sciences Beijing 100101 China Research School of Computer Science The Australian National University Canberra 0200 Australia

Line drawings, as a concise form, can be recognized by infants and even chimpanzees. Recently, how the visual system processes line-drawings attracts more and more attention from psychology, cognitive science and computer science. The neuroscientific studies revealed that line drawings generate similar neural actions as color photographs, which give insights on how to efficiently process big media data. In this paper, we present a comprehensive survey on line drawing studies, including cognitive mechanism of visual perception, computational models in computer vision and intelligent process in diverse media applications. Major debates, challenges and solutions that have been addressed over the years are discussed. Finally some of the ensuing challenges in line drawing studies are outlined.

关键词： line drawings cognitive computation visual media intelligent process

EXTENSION OF SMOOTHING FUNCTIONS TO SYMMETRIC CONE COMPLEMENTARITY PROBLEMS

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Applied Mathematics(A Journal of Chinese Universities) 2007年第2期22卷 245-252页

作者： liu yongjin Zhang Liwei liu Meijiao Department of Mathematics Shantou University Shantou 515063 China Department of Applied Mathematics Dalian University of Technology Dalian 116023 China Department of Mathematics and Physics Dalian Jiaotong University Dalian 116028 China

The paper uses Euclidean Jordan algebras as a basic tool to extend smoothing functions, which include the Chen-Mangasarian class and the Fischer-Burmeister smoothing functions, to symmetric cone complementarity problems. Computable formulas for these functions and their Jacobians are derived. In addition, it is shown that these functions are Lipschitz continuous with respect to parameter # and continuously differentiable on J × J for any μ 〉 0.

关键词： symmetric cone complementarity problem smoothing function Euclidean Jordan algebra non-interior continuation method

A computational cognition model of perception,memory,and judgment

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Science China(Information Sciences) 2014年第3期57卷 154-168页

作者： FU XiaoLan CAI LianHong liu Ye JIA Jia CHEN WenFeng YI Zhang ZHAO GuoZhen liu yongjin WU ChangXu State Key Laboratory of Brain and Cognitive Science Institute of PsychologyChinese Academy of Sciences TNLIST Department of Computer Science and TechnologyTsinghua University College of Computer Science Sichuan University Key Laboratory of Behavioral Science Institute of PsychologyChinese Academy of Sciences

The mechanism of human cognition and its computability provide an important theoretical foundation to intelligent computation of visual *** paper focuses on the intelligent processing of massive data of visual media and its corresponding processes of perception,memory,and judgment in *** particular,both the human cognitive mechanism and cognitive computability of visual media are investigated in this paper at the following three levels:neurophysiology,cognitive psychology,and computational modeling.A computational cognition model of Perception,Memory,and Judgment(PMJ model for short)is proposed,which consists of three stages and three pathways by integrating the cognitive mechanism and computability aspects in a unified ***,this paper illustrates the applications of the proposed PMJ model in five visual media research *** demonstrated by these applications,the PMJ model sheds some light on the intelligent processing of visual media,and it would be innovative for researchers to apply human cognitive mechanism to computer science.

关键词： perception memory judgment computational cognition model

Allogeneic compact bone-derived mesenchymal stem cell transplantation increases survival of mice exposed to lethal total body irradiation： a potential immunological mechanism

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Chinese Medical Journal 2014年第3期127卷 475-482页

作者： Qiao Shukai Ren Hanyun Shi yongjin liu Wei Department of Hematology Peking University First Hospital Beijing 100034 China

Background Radiation-induced injury after accidental or therapeutic total body exposure to ionizing radiation has serious pathophysiological consequences,and currently no effective therapy *** study was designed to investigate whether transplantation of allogeneic murine compact bone derived-mesenchymal stem cells （CB-MSCs） could improve the survival of mice exposed to lethal dosage total body irradiation （TBI）,and to explore the potential immunoprotective role of *** BALB/c mice were treated with 8 Gy TBI,and then some were administered CB-MSCs isolated from C57BL/6 *** rates and body weight were analyzed for 14 days *** three days post-irradiation,we evaluated IFN-Y and IL-4 concentrations; CD4＋CD25＋Foxp3＋ regulatory T cell （Treg） percentage; CXCR3,CCR5,and CCR7 expressions on CD3＋T cells; and splenocyte T-bet and GATA-3 mRNA ***-MSC effects on bone marrow hemopoiesis were assessed via colony-forming unit granulocyte/macrophage （CFU-GM） *** After lethal TBI,compared to non-transplanted mice,CB-MSC-transplanted mice exhibited significantly increased survival,body weight,and CFU-GM counts of bone marrow cells （P＜0.05）,as well as higher Treg percentages,reduced IFN-Y,CXCR3 and CCR5 down-regulation,and CCR7 ***-MSC transplantation suppressed Th1 *** splenocytes directly suppressed CFU-GM formation from bone marrow cells,and CB-MSC co-culture reversed this *** Allogeneic CB-MSC transplantation attenuated radiation-induced hematopoietic toxicity,and provided immunoprotection by alleviating lymphocyte-mediated CFU-GM inhibition,expanding Tregs,regulating T cell chemokine receptor expressions,and skewing the Th1/Th2 balance toward anti-inflammatory Th2 polarization.

关键词： mesenchymal stem cells transplantation total body irradiation colony-forming unit granulocyte/macrophage immunological mechanism

Exact-geodesic Voronoi Diagrams on Triangulated 2-Manifold and Topology-oriented Construction Algorithms

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Exact-geodesic Voronoi Diagrams on Triangulated 2-Manifold a...

基于功率矩和邻域搜索的有源配电网两层重构算法

第五届全国几何设计与计算学术会议

作者： yongjin liu Department of Computer Science and Technology Tsinghua University

Voronoi diagram is an elegant spatial structure which has found diverse applications in a variety of disciplines in natural *** this talk,we present study on a class of Voronoi diagrams on a triangulated 2-manifold setting *** analytic structures of iso-contours, bisectors,and Voronoi diagrams on M,based on exact geodesic metric,are studied in *** particular,compared to euclidean metric spaces,the Voronoi diagrams on M exhibit many special properties that fail all of the existing euclidean Voronoi *** provide practical algorithms for constructing geodesic metric based Voronoi diagrams on M,topology-oriented algorithms are constructed and implemented,which belong to the class of numerically robust geometric *** complexity of the construction algorithms is also ***, three interesting applications—surface sampling and reconstruction,3D skeleton extraction, and point pattern analysis—are presented that show the potential power of the proposed algorithms in pattern analysis.

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电力自动化设备 2017年第1期37卷 28-34页

作者：吉兴全刘琪于永进山东科技大学电气与自动化工程学院山东青岛266590

针对传统的含有分布式电源的配电网重构算法所存在的寻优速度和最终解的质量难以兼顾的问题,提出一种基于功率矩和邻域搜索的配电网两层重构算法。利用功率矩算法对各环路进行第一层重构优化,确定开断支路集,在此基础上采用具有方向的... 详细信息

针对传统的含有分布式电源的配电网重构算法所存在的寻优速度和最终解的质量难以兼顾的问题,提出一种基于功率矩和邻域搜索的配电网两层重构算法。利用功率矩算法对各环路进行第一层重构优化,确定开断支路集,在此基础上采用具有方向的邻域搜索算法进行第二层重构。通过对当前解点的邻域搜索获取更优的解点位置,直至目标函数值不再下降,从而得到最终的重构方案。含有分布式电源的IEEE 33和IEEE 69节点典型测试系统的仿真结果验证了所提算法的有效性。

关键词：配电网分布式电源重构功率矩邻域搜索

数字几何处理中Laplace-Beltrami算子的离散化理论与应用研究综述

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计算机辅助设计与图形学学报 2015年第4期27卷 559-569页

作者：范典刘永进贺英清华大学计算机系北京100084 清华信息科学与技术国家实验室(筹) 北京100084 南洋理工大学计算机学院

数字几何处理的主要研究对象是三维空间中的二维曲面,Laplace-Beltrami算子是定义在黎曼流形上的微分算子,其在网格曲面上的离散形式在三维模型分析等应用中具有重要作用,是一类基本的几何工具.不同的离散方法具有不同的数学性质,所适... 详细信息

数字几何处理的主要研究对象是三维空间中的二维曲面,Laplace-Beltrami算子是定义在黎曼流形上的微分算子,其在网格曲面上的离散形式在三维模型分析等应用中具有重要作用,是一类基本的几何工具.不同的离散方法具有不同的数学性质,所适用的应用场景也不相同.文中对Laplace-Beltrami算子的离散化理论与应用进行综述,希望能够使读者对该算子的功能有基本了解,对数字几何处理的最新研究进展有进一步的认识,并对未来的研究方向及应用前景有所启发.

关键词：计算机图形学数字几何 Laplace-Beltrami算子离散化

OQAM/OFDM系统中基于信道估计的原型滤波器设计

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系统工程与电子技术 2020年第1期42卷 191-197页

作者：刘永进陈西宏空军工程大学防空反导学院

针对正交频分复用/交错正交幅度调制系统频率选择性信道,提出了基于信道估计的原型滤波器设计方案。就其导频频谱效率低的问题,提出了能够提高频谱效率的导频结构,并进行了信道估计。用信号与干扰加噪声比的倒数衡量原型滤波器对信道估... 详细信息

针对正交频分复用/交错正交幅度调制系统频率选择性信道,提出了基于信道估计的原型滤波器设计方案。就其导频频谱效率低的问题,提出了能够提高频谱效率的导频结构,并进行了信道估计。用信号与干扰加噪声比的倒数衡量原型滤波器对信道估计的影响并将其作为优化问题的约束条件之一,将最小化阻带能量作为目标函数,对原型滤波器的设计问题进行建模。为了加快收敛速度,保证获得全局最优解,利用基于块的分支定界法对原型滤波器的优化问题进行求解。仿真结果证明了所提方法的有效性。

关键词：正交频分复用/交错正交幅度调制信道估计原型滤波器设计信号与干扰加噪声比的倒数