检索结果-内蒙古大学图书馆

3D Ear Shape Matching Using Joint -Entropy

Journal of Computer Science & Technology 2015年第3期30卷 565-577页

作者：孙晓鹏李思慧韩枫魏小鹏 Institute of Computer Systems School of Computer and Information Technology Liaoning Normal University Dalian 116029 China Beijing Key Laboratory of Intelligent Telecommunications Software and Multimedia Beijing University of Posts and Telecommunications Beijing 100876 China School of Mechanical and Engineering Dalian University of Technology Dalian 116024 China Key Laboratory of Advanced Design and Intelligent Computing Dalian University Dalian 116622 China

In this article, we investigate the use of joint a-entropy for 3D ear matching by incorporating the local shape feature of 3D ears into the joint a-entropy. First, we extract a sut^cient number of key points from the 3D ear point cloud, and fit the neighborhood of each key point to a single-value quadric surface on product parameter regions. Second, we define the local shape feature vector of each key point as the sampling depth set on the parametric node of the quadric surface. Third, for every pair of gallery ear and probe ear, we construct the minimum spanning tree （MST） on their matched key points. Finally, we minimize the total edge weight of MST to estimate its joint a-entropy the smaller the entropy is, the more similar the ear pair is. We present several examples to demonstrate the advantages of our algorithm, including low time complexity, high recognition rate, and high robustness. To the best of our knowledge, it is the first time that, in computer graphics, the classical information theory of joint a-entropy is used to deal with 3D ear shape recognition.

关键词： joint a-entropy minimum spanning tree local shape feature ear matching ear recognition

来源：评论

学校读者我要写书评

暂无评论

An Improved Virtual Spherical Lights Approach for Glossy Illumination

引用

Computer Aided Drafting,design and Manufacturing 2015年第1期25卷 74-80页

作者： DONG Jing WANG Lan BAI Shuang-xue Key Laboratory of Advanced Design and Intelligent Computing (Dalian University) Ministry of Education

Based on a virtual spherical light source method, this paper presents an improved virtual spherical lights approach for glossy illumination by modifying a reflection render equation. First, in order to keep primitive spherical lights, it uses non-zero solid angle integration instead of a geometric item of traditional Instant Radiosity arithmetic. Second, the formula mode for the light energy allocation of VSLs is improved by the energy distribution, in which the radius of sphere is replaced by the radius of inscribed circle generated by the tangent to the non-zero solid angle of cone. Third, the similar function of judging two point visibility takes place of a cosine term in the approximate equations of the VSLs. Experiments show that blurring or disappearing phenomenon that appear in part of right-angle surface scene is avoided.

关键词： virtual spherical lights glossy rendering global illumination rendering

来源：评论

学校读者我要写书评

暂无评论

Trajectory Planning of 7-DOF Space Manipulator for Minimizing Base Disturbance

引用

International Journal of advanced Robotic Systems 2016年第2期13卷 44-44页

作者： Qiang Zhang Lan Wang Dongsheng Zhou Key Laboratory of Advanced Design and Intelligent Computing Ministry of Education Dalian University Dalian China

In the free-floating mode, there is intense dynamic coupling existing between the space manipulator and the base, and the base attitude may change while performing a motion with its manipulator. Therefore, it is necessary to reduce the interference that resulted from the manipulator movement. For planning trajectories of the space manipulator with 7 degrees of freedom (7-DOF), simulated annealing particle swarm optimization (SAPSO) algorithm is presented in the paper. Firstly, kinematics equations are setup. Secondly, the joint functions are parameterized by sinusoidal functions, and the objective function is defined according to the motion constraints of manipulator and accuracy requirements of the base attitude. Finally, SAPSO algorithm is used to search the optimal trajectory. The simulation results verify the proposed method.

关键词： Space Manipulator 7-DOF Base Attitude SAPSO Algorithm

来源：评论

学校读者我要写书评

暂无评论

An Image Encryption Scheme Based on DNA computing and Cellular Automata

引用

Discrete Dynamics in Nature and Society 2016年第1期2016卷

作者： Shihua Zhou Bin Wang Xuedong Zheng Changjun Zhou Key Laboratory of Advanced Design and Intelligent Computing Dalian University Ministry of Education Dalian 116622 ***

Networks have developed very quickly, allowing the speedy transfer of image information through Internet. However, the openness of these networks poses a serious threat to the security of image information. The field of image encryption has drawn attention for this reason. In this paper, the concepts of 1-dimensional DNA cellular automata and T-DNA cellular automata are defined, and the concept of reversible T-DNA cellular automata is introduced. An efficient approach to encryption involving reversible T-DNA cellular automata as an encryption tool and natural DNA sequences as the main keys is here proposed. The results of a simulation experiment, performance analysis, and comparison to other encryption algorithms showed this algorithm to be capable of resisting brute force attacks, statistical attacks, and differential attacks. It also enlarged the key space enormously. It meets the criteria for one-time pad and resolves the problem that one-time pad is difficult to save.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Optimal Path Planning for Minimizing Base Disturbance of Space Robot

引用

International Journal of advanced Robotic Systems 2016年第2期13卷 41-41页

作者： Xiao-Peng Wei Jian-Xia Zhang Dong-Sheng Zhou Qiang Zhang School of Mechanical Engineering Dalian University of Technology Dalian China Key Laboratory of Advanced Design and Intelligent Computing Ministry of Education Dalian University Dalian China

The path planning of free-floating space robot in space on-orbit service has been paid more and more attention. The problem is more complicated because of the interaction between the space robot and base. Therefore, it is necessary to minimize the base position and attitude disturbance to improve the path planning of free-floating space robot, reducing the fuel consumption for the position and attitude maintenance. In this paper, a reasonable path planning method to solve the problem is presented, which is feasible and relatively simple. First, the kinematic model of 6 degrees of freedom free-floating space robot is established. And then the joint angles are parameterized using the 7th order polynomial sine functions. The fitness function is defined according to the position and attitude of minimizing base disturbance and constraints of space robot. Furthermore, an improved chaotic particle swarm optimization (ICPSO) is presented. The proposed algorithm is compared with the standard PSO and CPSO algorithm in the literature by the experimental simulation. The simulation results demonstrate that the proposed algorithm is more effective than the two other approaches, such as easy to find the optimal solution, and this method could provide a satisfactory path for the free-floating space robot.

关键词： ICPSO Path Planning Base Disturbance Space Robot On-orbit Service

来源：评论

学校读者我要写书评

暂无评论

Optimization design of Close-top Mill Housing Based on Agent Model and NSGA-Ⅱ Algorithm

Optimization design of Close-top Mill Housing Based on Agent...

引用

2015 5th International Conference on Information Engineering for Mechanics and Materials(ICIMM 2015)

作者： Yanjun Shi Xianchao Wang Xiaojun Zheng School of Mechanical Engineering Dalian University of Technology Key Laboratory of Advanced Design and Intelligent Computing Ministry of Education of Dalian University

Conventional engineering optimization design technology is often computational expense and highly time cost, thus we need to take approximation technique to speed up the design process and reduce design cost. We herein would introduce the close-top mill housing optimization model, take Optimal Latin Hypercube Sampling（OLHS） experimental design strategies to determine the sample, analyse the difference among EBF, RBF, Kriging surrogate model, introduce NSGA-II algorithm briefly and study the performance of method based on surrogate model and optimization algorithm.

关键词： EBF-NN RBF-NN Kriging NSGA-II Mill housing Surrogate models

来源：评论

学校读者我要写书评

暂无评论

Analyzing the loading capacity of autofrettage thick cylinder with a response surface surrogate model

Analyzing the loading capacity of autofrettage thick cylinde...

引用

2015 5th International Conference on Information Engineering for Mechanics and Materials(ICIMM 2015)

作者： YanJun Shi Chenglong Liu XiaoJun Zheng School of Mechanical Engineering Dalian University of Technology Key Laboratory of Advanced Design and Intelligent Computing Ministry of Education of Dalian University

The paper analyzed a steel thick cylinder, established a bilinear kinematic hardening model based on the von Mises yield criterion. We also considered the parameters of the material yield limit, the autofrettage pressure, working pressure and cylinder diameters, studied of a response surface model to predict design parameters. We firstly used the optimal Latin Hypercube method to acquire the sample points. Then, we established a response surface model with these points. We also employed cross-validation error analysis for error analysis. The results tested the feasibility of this method in solving such problems.

关键词： von Mises autofrettage pressure response surface model optimal latin hypercube

来源：评论

学校读者我要写书评

暂无评论

Comparison study of Gauss, MQ and TPS for interpolation application

引用

International Journal of Industrial and Systems Engineering 2014年第2期18卷 185-198页

作者： Zhang, Qiang Zheng, Guangguo Zhou, Dongsheng Key Laboratory of Advanced Design and Intelligent Computing Ministry of Education Dalian University Dalian 116622 China

There are mainly two parts in this paper. In the first part, we briefly introduce the basic theory of the radial basis function (RBF) and its application in scattered data interpolation, and investigate the difference among three kernel functions: multi-quadric, Gauss and thin plate spline, in detail. According to the multiple examples, we make a lot of experiments, and develop a system in the C++ programme language and the OpenGL open graphics library to make simulation experiments. Finally, we analyse and summarise the different characteristics of the each kernel function in the process of interpolation. In addition, on the basis of the well-known interpolation theory and the analysis of the experimental data, we list several examples for interpolation comparisons. In the second part, the distance of the current marked points down to its most neighbouring marked points is used as shape parameter. Combining with other shape parameter for analysis and comparisons, the results represent the different influences of RBF shape parameter on the curve and surface construction. Our experiment results obtained in this article have theoretical guide values in graphic interpolation modelling. Copyright © 2014 Inderscience Enterprises Ltd.

关键词： Interpolation

来源：评论

学校读者我要写书评

暂无评论

Time-varying stiffness analysis on rotating shaft with elliptical-front crack

引用

International Journal of Industrial and Systems Engineering 2014年第3期17卷 302-314页

作者： Wei, Xiaopeng Liu, Dajun Zhao, Lasheng Zhang, Qiang Key Laboratory of Advanced Design and Intelligent Computing Dalian University Ministry of Education Dalian 116622 China

The aim of this paper is to investigate the difference of time-varying stiffness characteristics between a semi-elliptical front crack and a straight front crack of shaft-element in order to obtain a more accurate and realistic cracked-rotor model for rotating machinery system. By calculating the correct time-varying area moments of inertia for the cross-section of cracked element and taking account the neutral axis position changes, the switching function is obtained, meanwhile the stiffness of shaft in a steady rotating cycle is determined. The result shows that a significant difference of stiffness appears as crack depth deepens. Especially, the difference between elliptical-front (EF) and straight-front (SF) cracked element is more obvious in the early crack propagation. © 2014 Inderscience Enterprises Ltd.

关键词： Cracks

来源：评论

学校读者我要写书评

暂无评论

Contact-based motion graph and its application in locomotion synthesis for virtual actors

引用

International Journal of Industrial and Systems Engineering 2015年第1期20卷 58-68页

作者： Wei, Xiaopeng Yi, Pengfei Zhang, Qiang School of Mechanical and Engineering Dalian University of Technology Dalian116024 China Key Laboratory of Advanced Design and Intelligent Computing Ministry of Education Dalian University Dalian116622 China

To generate foot-skate free locomotion along user defined path for virtual actors, a novel data structure of contact-based motion graph is proposed. At first, sample motions are divided to contact clips according to the number of feet in contact with the ground. Then a directed graph can be built by producing nodes and basic edges based on these clips. After generating edges between nodes from different samples by linear interpolation, the contact-based motion graph can be defined as a strongly connected component of this graph. Applying synthesis strategy designed for nodes and edges, a path on contact-based motion graph can be converted to a smooth foot-skate free motion moving along the given path. The following experiments show the effectiveness of this method. Copyright © 2015 Inderscience Enterprises Ltd.

关键词： Directed graphs

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：