检索结果-内蒙古大学图书馆

Analytical solution of average path length for Apollonian networks

Physical Review E 2008年第1期77卷 017102-017102页

作者： Zhongzhi Zhang Lichao Chen Shuigeng Zhou Lujun Fang Jihong Guan Tao Zou Department of Computer Science and Engineering Fudan University Shanghai 200433 China Shanghai Key Laboratory of Intelligent Information Processing Fudan University Shanghai 200433 China Department of Computer Science and Technology Tongji University 4800 Cao’an Road Shanghai 201804 China

With the help of recursion relations derived from the self-similar structure, we obtain the solution of average path length, d¯t, for Apollonian networks. In contrast to the well-known numerical result d¯t∝(ln Nt)3/4 [J. S. Andrade, Jr. et al., Phys. Rev. Lett. 94, 018702 (2005)], our rigorous solution shows that the average path length grows logarithmically as d¯t∝ln Nt in the infinite limit of network size Nt. The extensive numerical calculations completely agree with our closed-form solution.

关键词： SCALE-FREE NETS SMALL-WORLD COMPLEX NETWORKS DYNAMICS GRAPHS

来源：评论

学校读者我要写书评

暂无评论

Multi-Agent Classifiers Fusion Strategy for Biomedical Named Entity Recognition

Multi-Agent Classifiers Fusion Strategy for Biomedical Named...

引用

International Conference on BioMedical Engineering and Informatics (BMEI)

作者： Haochang Wang Tiejun Zhao Jianmiao Liu Daqing Petroleum Institute College of Computer and Information Technology Daqing China Speech in Harbin Institute of Technology MOE-MS Key Laboratory of Natural Language Processing Harbin China

Recognizing the biomedical named entity has become one of the most fundamental tasks in the biomedical knowledge discovery. The multi-agent classifiers fusion approach proposed here was found to efficiently recognize biomedical named entity. We employ conditional random fields as our underlying classifier model and incorporate diverse set of features into system, the relativity between classifiers is utilized by using co-decision matrix to exchange decision information among classifiers. The experiments are carried on GENIA corpus with the best result of 77.88% F-sore. The multi-agent classifier fusion strategy proposed here is obviously superior to the individual classifier based method and more effective than the classifiers fusion approach of boosting and bagging.

关键词： Hidden Markov models Speech recognition Machine learning algorithms Machine learning Biomedical engineering Biomedical informatics Educational institutions Biomedical computing information technology Petroleum

来源：评论

学校读者我要写书评

暂无评论

Multiword Expression Recognition Using Multiple Sequence Alignment

Multiword Expression Recognition Using Multiple Sequence Ali...

引用

International Conference on Advanced Language processing and Web information technology (ALPIT)

作者： Ru Li Lijun Zhong Jianyong Duan School of Computer and Information Technology Shanxi University Taiyuan Shanxi China Chinese Information Processing of Ministry of Education Key Laboratory of Computational Intelligence Taiyuan Shanxi China Computer Science and Engineering North-China University of Technology Beijing China

For the Multiword Expression (MWE) recognition, the Multiple Sequence Alignment (MSA) is proposed on the motivation of gene recognition. Because textual sequence is similar to gene sequence in pattern analysis. This MSA technique is combined with error-driven rules, with the improved efficiency beyond the traditional *** provides a guarantee for the MWE recall. It uses the dynamic programming method to prevent candidates from combinational explosion, and provides a global solution for pattern extraction instead of sub-pattern redundancy. Consequently, it has accurate measures for flexible patterns. In experiment, some advanced statistical measures are performed for ranking candidates. In the comparison experiment, the MSA approach achieved better results.

关键词： Feature extraction Data mining Dynamic programming Noise information filters information filtering Statistical analysis

来源：评论

学校读者我要写书评

暂无评论

An Improved Markov Chain Monte Carlo Scheme for Parameter Estimation Analysis

An Improved Markov Chain Monte Carlo Scheme for Parameter Es...

引用

International Symposium on Intelligent information technology Application, IITA

作者： Fang Liu Hao Pan Desheng Jiang Jianzhong Zhou School of Computer Science and Technology Wuhan University of Technology China Key Laboratory of Fiber Optic Sensing Technology and Information Processing of Ministry of Education Wuhan University of Technology China School of Hydropower and Information Engineering Huazhong University of Science and Technology China

Aiming at resolving the issue of designing appropriate proposal distribution in Markov Chain Monte Carlo (MCMC) algorithm, an improved MCMC scheme is developed in this paper. The presented scheme employs normal density distribution as proposal distribution to sample in objective function, and together with the historical sampling information, the proposal distribution runs to proper distribution by adaptive self-regulation. The improved scheme is applied to parameter estimation of Pearson-III distribution to figure out the problems of runoff frequency forecast. In the case study of annual runoff frequency calculation of Fengtan reservoir, satisfying results are obtained, and compared with the genetic algorithm and the traditional weight function method, the new scheme can not only provide the proper posterior distribution, but also the related statistical information of parameters, which are useful for parameter estimation of complex modeling and uncertainty analysis.

关键词： Monte Carlo methods Parameter estimation Proposals Algorithm design and analysis Frequency estimation Sampling methods Reservoirs Genetic algorithms Uncertainty information analysis

来源：评论

学校读者我要写书评

暂无评论

Cryptanalysis of the Chaotic-based key Agreement Protocols

Cryptanalysis of the Chaotic-based Key Agreement Protocols

引用

2008 International Symposium on Biometrics and Security Technologies (ISBAST'08)

作者： Xianfeng Guo Jiashu Zhang College of Computer Science and Technology Southwest University of Nationalities of China Chengdu China Sichuan Key Laboratory of Signal and Information Processing Southwest Jiaotong University Chengdu China

Recently, Han-Chang showed that Xiao-Liao-Deng's key agreement protocol based on chaotic maps is vulnerable to man-in-the-middle attack and proposed two improved schemes. One works in clock synchronization, and the other can work without synchronization. They claimed that their schemes are secure against replaying attacks and can establish a shared session key. However, we point out that all the aforementioned schemes are Non-contributory, i.e. the malicious party can predetermine the shared session key by the vice of several Chebyshev polynomials passing through the same point. In particular, we demonstrate that the asynchronous key agreement protocol can't resist replaying attack. Therefore, the use of these schemes for secure applications may be discouraged.

关键词： Chaos key agreement Chebyshev Semi-group Property Contributory nature

来源：评论

学校读者我要写书评

暂无评论

Three-dimensional ISAR imaging based on antenna array

Three-dimensional ISAR imaging based on antenna array

引用

作者： Ma, Changzheng Yeo, Tat Soon Zhang, Qun Tan, Hwee Siang Wang, Jun IEEE School of Electric and Information Engineering Zhongyuan University of Technology Zhengzhou 450007 China Department of Electrical and Computer Engineering National University of Singapore Singapore 117576 Singapore Institute of Telecommunication Engineering Air Force Engineering University Xi'an 710071 China National Key Laboratory of Radar Signal Processing Xidian University Shaanxi 710071 China

In this paper, a 3-D inverse synthetic aperture radar (ISAR) imaging method based on an antenna array configuration is proposed. The performance of conventional interferometric ISAR imaging system using three antennas is poor, as the positions of scatterers, which have the same range-Doppler value and projected onto the ISAR plane as a synthesis scatterer, cannot be correctly estimated. However, by using two antenna arrays perpendicular to each other, the system's ability to separate these scatterers can be improved. The criterion for the selection of a range unit that contains an isolated scatterer in the 2-D array domain for doing motion compensation is discussed. If there is no range unit which contains only an isolated scatterer, then radial and cross-range motion compensation has to be carried out by motion parameter estimation. Two cross-range motion parameters measurement algorithms, one based on array processing of the range profile and another based on correlation of ISAR images of different antennas, are proposed. The coordinates registration problem for the scatterers of a synthesis scatterer is also discussed. Simulation results have shown the effectiveness of the proposed methods. © 2008 IEEE.

关键词： Synthetic aperture radar

来源：评论

学校读者我要写书评

暂无评论

Improved ant colony algorithm for the VRPSPD with maximum distance constraint

引用

Xitong Gongcheng Lilun yu Shijian/System Engineering Theory and Practice 2008年第1期28卷 132-140+169页

作者： Zhang, Tao Tian, Wen-Xin Zhang, Yue-Jie Liu, Shi-Xin School of Information Management and Engineering Shanghai University of Finance and Economics Shanghai 200433 China Informatization Office in Center of Modern Education Technology Shanghai Finance University Shanghai 201209 China Shanghai Key Laboratory of Intelligent Information Processing Department of Computer Science and Engineering Fudan University Shanghai 200433 China Key Laboratory of Integrated Automation of Process Industry School of Information Science and Engineering Northeastern University Shenyang 110004 China

This paper studies the reverse logistics vehicle routing problem of simultaneous distribution of commodities and collection of reusable ones the same size as the initial state with a single depot and a homogeneous fleet of vehicles with limited capacities and maximum distance, and constructs a mixed integer programming model. To solve this problem, an Ant Colony System (ACS) approach combining with the pheromone updating strategy of ASRank (Rank-based Version of Ant System) and MMAS (MAX-MIN Ant System) is proposed. A new heuristic factor is designed to improve the vehicle loading ability as well as the vehicle distance, and the initial vehicle load is designed to be a random value correlated to the delivery and pick-up demand of the rest customers on the path. The experimental study indicates that the approach could improve the vehicle load rate and get rid of the additional total distance caused by the fluctuating vehicle load and the limited capacity. It could obtain the satisfied solution with high convergence speed in the acceptable time.

关键词： Systems engineering

来源：评论

学校读者我要写书评

暂无评论

Node-failure tolerance of topology in wireless sensor networks

引用

International Journal of Network Security 2008年第2期7卷 261-264页

作者： Wang, Liang-Min Ma, Jian-Feng Guo, Yuan-Bo The Computer School Jiangsu University Zhenjiang 212013 China Key Laboratory of Computer Network and Information Security of Education Ministry Xidian University Xi'an Shaanxi 710071 China School of Electronic Technology Engineering University of PLA Zhengzhou 450004 China

Three basic questions are presented and answered in researching on nodefailure topology in wireless sensor network. First, what is the definition of nodefailure tolerance? Second, how to evaluate this tolerance abilit... 详细信息

关键词： Sensor nodes

来源：评论

学校读者我要写书评

暂无评论

Image segmentation using dynamic mechanism based PCNN model

Image segmentation using dynamic mechanism based PCNN model

引用

International Joint Conference on Neural Networks (IJCNN)

作者： Yuanhua Qiao Jun Miao Lijuan Duan Yunfeng Lu College of Applied Science Beijing University of Technology Beijing China Institute of Computing Technology and the Key Laboratory of Intelligent Information Processing Chinese Academy and Sciences Beijing China College of Computer Science and Technology Beijing University of Technology Beijing China

Pulse-coupled neuron networks (PCNN) can be efficiently applied to image segmentation. However, the performance of segmentation depends on the suitable PCNN parameters, which are obtained by manual experiment, and the effect of the segmentation needs to be improved for images with noise. In this paper, dynamic mechanism based PCNN(DMPCNN) is brought forward to simulate the integrate-and-fire mechanism, and it is applied to segment images with noise effectively. Parameter selection is based on dynamic mechanism. Experimental results for image segmentation show its validity and robustness.

关键词： Neurons Image segmentation Couplings Mathematical model Equations Fires Artificial neural networks

来源：评论

学校读者我要写书评

暂无评论

Mahalanobis distance based Polynomial Segment Model for Chinese Sign Language Recogniton

Mahalanobis distance based Polynomial Segment Model for Chin...

引用

IEEE International Conference on Multimedia and Expo (ICME)

作者： Yu Zhou Xilin Chen Debin Zhao Hongxun Yao Wen Gao School of Computer Science and Technology Harbin Institute of Technology Harbin China Key Laboratory of Intelligent Information Processing Institute of Computing Technology Chinese Academy and Sciences Beijing China Institute of Digital Media Peking University Beijing China

Sign Language Recognition (SLR) systems are mostly based on Hidden Markov Model (HMM) and have achieved excellent results. However, the assumption of frame independence in HMM makes it inconsistent with the characteristic of strong temporal correlation in sign language signals. Polynomial Segment Model (PSM) explicitly represents the temporal evolution of sign language features as a Gaussian process with time-varying parameters. In this paper PSM is first introduced to SLR framework to solve the temporal correlation problem. Considering the correlation among the coefficients of polynomial trajectorypsilas different orders, Mahalanobis distance is used as the classification criterion to evaluate the likelihood of test data. Experimental results show that our method outperform the conventional HMM methods by 6.81% in recognition accuracy.

关键词： Hidden Markov models Handicapped aids Distance measurement Trajectory Vocabulary Euclidean distance Polynomials

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：