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Integrating Audio-Visual Features and Text Information for Story Segmentation of News Video

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wuhan university Journal of Natural Sciences 2003年第4A期8卷 1070-1074页

作者： Liu Hua-yong, Zhou Dong-ru  school of computer,wuhan university,wuhan 430072, hubei, China school of computer Wuhan University Wuhan Hubei China

Video data are composed of multimodal information streams including visual, auditory and textual streams, so an approach of story segmentation for news video using multimodal analysis is described in this paper. The proposed approach detects the topic-caption frames, and integrates them with silence clips detection results, as well as shot segmentation results to locate the news story boundaries. The integration of audio-visual features and text information overcomes the weakness of the approach using only image analysis techniques. On test data with 135 400 frames, when the boundaries between news stories are detected, the accuracy rate 85.8% and the recall rate 97.5% are obtained. The experimental results show the approach is valid and robust.

关键词： news video story segmentation audio-visual features analysis text detection

A Distributed Routing and Wavelength Assignment Algorithm for Online Multicast in All-Optical WDM Networks

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wuhan university Journal of Natural Sciences 2002年第1期7卷 27-36页

作者： Huang Chuan-he, Chen Xin-meng, Jia Xiao-hua school of computer, wuhan university, wuhan 430072, hubei, China school of computer Wuhan University Wuhan Hubei China

Routing and wavelength assignment for online real-time multicast connection setup is a difficult task due to the dynamic change of availabilities of wavelengths on links and the consideration of wavelength conversion delay in WDM networks. This paper presents a distributed routing and wavelength assignment scheme for the setup of real-time multicast connections. It integrates routing and wavelength assignment as a single process, which greatly reduces the connection setup time. The proposed routing method is based on the Prim’s MST (Minimum Spanning Tree) algorithm and the K-restricted breadth-first search method, which can produce a sub-minimal cost tree under a given delay bound. The wave-length assignment uses the least-conversion and load balancing strategies. Simulation results show that the proposed algorithm is suitable for online multicast connection establishment in WDM networks.

关键词： Key words WDM networks routing and wavelength assignment multicast routing delay bounded routing

Drift Analysis in Studying the Convergence and Hitting Times of Evolutionary Algorithms: An Overview

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wuhan university Journal of Natural Sciences 2003年第S1期8卷 143-154页

作者： He Jun, Yao Xin1.State Laboratory of Software Engineering, wuhan university, wuhan 430072, hubei,China 2.school of computer Science, university of Birmingham, Birmingham B15 2TT, England State Laboratory of Software Engineering Wuhan University Wuhan Hubei China school of computer Science University of Birmingham Birmingham England

This paper introduces drift analysis approach in studying the convergence and hitting times of evolutionary algorithms. First the methodology of drift analysis is introduced, which links evolutionary algorithms with Markov chains or supermartingales. Then the drift conditions which guarantee the convergence of evolutionary algorithms are described. And next the drift conditions which are used to estimate the hitting times of evolutionary algorithms are presented. Finally an example is given to show how to analyse hitting times of EAs by drift analysis approach.

关键词： evolutionary algorithms convergence hitting time drift analysis

A PRICE-SETTING NEWSVENDOR MODEL UNDER CVAR DECISION CRITERION WITH EMERGENCY PROCUREMENT

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Journal of Systems Science and Systems Engineering 2010年第1期19卷 85-104页

作者： Minghui XU school of Economics and Management,wuhan university,wuhan 430072,China school of Economics and Management Wuhan University Wuhan China

In this paper, we consider a newsvendor model in which a risk-averse manager faces a stochastic price-dependent demand in either an additive or a multiplicative form. An emergency purchase option is allowed after the realization of demand to satisfy the units that are short. By adopting Conditional value-at-risk （CVaR） as the decision criterion, we aim to investigate the optimal pricing and ordering decisions, and the effects of parameter changes in such a setting. We provide sufficient conditions for the uniqueness of the optimal policy for both demand models. We perforl~, comparative statics analysis to show how the optimal pricing and ordering decision behaves when changing parameters. We also compare our results with those of the newsvendor with a general utility function and with CVaR criterion under lost sales assumption. Our key results include：（i） For both demand models, the optimal selling price is decreasing in risk aversion. Hence, the optimal price of a risk-averse newsvendor is not greater than the optimal price of a risk-neutral newsvendor. （it） In contrary to the lost sales case, for the multiplicative demand model, the optimal order quantity may not be monotonic in risk aversion. Consequently, the optimal risk-averse order quantity may be lower or higher than the optimal risk- neutral counterpart. （iii） For the additive model, the optimal order quantity is strictly increasing in the emergency purchase price, while for the multiplicative model the optimal order quantity has no such a monotonic property. Some numerical examples are conducted to verify our claims and gain more insights about the risk-averse decision-making behaviors.

关键词： Newsvendor model inventory pricing risk aversion conditional value-at-risk

Electronic Structure of Doped Trans-Polyacetylene

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wuhan university Journal of Natural Sciences 2002年第1期7卷 51-53页

作者： Ren Da-zhi 1,2, Zhuang Wei 2, Wang Jun 2 1. wuhan university Journals Press,wuhan 430072,hubei,China 2. school of Physics and Technology, wuhan university, wuhan 430072,hubei,China wuhan university Journals Press Wuhan Hubei China school of Physics and Technology Wuhan University Wuhan Hubei China

The behavior of electronic structures of doped trans-polyacetylene is revealed by a simple method. (C24H26)+n is used to simulate p-type doped trans-polyacetylene at various doping concentrations. The electronic structure is calculated, by CNDO/2 method. These calculations show that at low doping level, the decrease of electronic energy compensates the increase of elastic energy, thus the bond alternation exists, and the charge carriers are solitons. When doping level is high, the increase of elastic energy is larger than the decrease, of electronic energy, the bond alternation disappears, solitons no longer exist, and polyacetylene is in a metalic state.

关键词： trans polyacetylene CNDO/2 electronic structure doped

A Hybrid Genetic Algorithm for Reduct of Attributes in Decision System Based on Rough Set Theory

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wuhan university Journal of Natural Sciences 2002年第3期7卷 285-289页

作者： Dai Jian\|hua 1,2 , Li Yuan\|xiang 1,2 ,Liu Qun 3 1. State Key Laboratory of Software Engineering, wuhan university, wuhan 430072, hubei,China 2. school of computer, wuhan university, wuhan 430072, hubei, China 3. school of computer Science, Lab. of Software Eng. Wuhan Univ. Wuhan 430072 China Sch. of Comp. Wuhan Univ. Wuhan 430072 China Sch. of Comp. Sci. Chongqing Univ. of Post and Telecom. Chongqing 400065 China

Knowledge reduction is an important issue when dealing with huge amounts of data. And it has been proved that computing the minimal reduct of decision system is NP-complete. By introducing heuristic information into genetic algorithm, we proposed a heuristic genetic algorithm. In the genetic algorithm, we constructed a new operator to maintaining the classification ability. The experiment shows that our algorithm is efficient and effective for minimal reduct, even for the special example that the simple heuristic algorithm can’t get the right result.

关键词： rough set reduction genetic algorithm heuristic algorithm

Research and Implementation of Unsupervised Clustering-Based Intrusion Detection

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wuhan university Journal of Natural Sciences 2003年第3A期8卷 803-807页

作者： Luo Min, Zhang Huan\|guo, Wang Li\|na school of computer, wuhan university, wuhan 430072, hubei, China school of computer Wuhan University Wuhan Hubei China

An unsupervised clustering\|based intrusion detection algorithm is discussed in this paper. The basic idea of the algorithm is to produce the cluster by comparing the distances of unlabeled training data sets. With the classified data instances, anomaly data clusters can be easily identified by normal cluster ratio and the identified cluster can be used in real data detection. The benefit of the algorithm is that it doesn't need labeled training data sets. The experiment concludes that this approach can detect unknown intrusions efficiently in the real network connections via using the data sets of KDD99.

关键词： intrusion detection data mining unsupervised clustering unlabeled data

Mathematical Model of the Identical Slope Surface

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wuhan university Journal of Natural Sciences 2002年第1期7卷 54-58页

作者： Hu Jian-guo 1, Chen yue-ping 2 1. school of Urban Studies,wuhan university,wuhan 430072, hubei, China 2.College of Politics and Administration,wuhan university, wuhan 430072,hubei, China school of Urban Studies Wuhan University Wuhan Hubei China College of Politics and Administration Wuhan University Wuhan Hubei China

The formation of the identical slope surface and the method of construction are discussed. On the basement of building the parameter equation of variable-radius circle family envelope, the frequently used parameter equation of the identical slope surface of the top of taper moving along column helix, horizental arc and line is built. The equation can be used to construct the identical slope surface’s contours, gradient lines and three dimensional figures correctly.

关键词： Key words identical slope surface family of circles mathematical model envelope elevation projection contours

Non-Homogeneous Riemann Boundary Value Problem with Radicals

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wuhan university Journal of Natural Sciences 2002年第4期7卷 379-382页

作者： Lu Jian-ke school of Mathematics and Statistics,wuhan university,wuhan 430072, hubei,China school of Mathematics and Statistics Wuhan University Wuhan Hubei China

The solution of the non-homogeneous Riemann boundary value problem with radicals (1. 2) together with its condition of solvability is obtained for arbitrary positive integersp andq, which generalizes the results for t... 详细信息

关键词： Riemann boundary value problem branch points of radicals index order at infinity sectionally holomorphic functions