检索结果-南通市图书馆

TWO-AGENT PARETO OPTIMAL COOPERATIVE INVESTMENT IN INCOMPLETE MARKET:AN EQUIVALENT CHARACTERIZATION

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2011年第4期24卷 701-710页

作者： Qing ZHOU School of Science Beijing University of Posts and Telecommunications Beijing 100876 China.

This paper studies the following cooperative investment game with two agents. At the start of the game, both the agents＇ capital are collected. The total capital are then invested according to a certain trading strategy. At a certain time To one agent quits the cooperation and they divide the wealth among themselves. During the remaining period [To, T], the other agent invests his/her capital following a possibly different trading strategy. By stochastic optimization method combined with the theory of Backward Stochastic Differential Equations （BSDEs, for short）, we give an equivalent characterization of the Pareto optimal cooperative strategies.

关键词： Backward stochastic differential equation cooperative investment incomplete market,Pareto optimum stochastic utility.

Search recommendation model based on user search behavior and gradual forgetting collaborative filtering strategy

在线全文

学校读者我要写书评

暂无评论

The Journal of china Universities of posts and telecommunications 2010年第3期17卷 110-117页

作者： LIU Chuan-chang State Key Laboratory of Networking and Switching Technology, beijing university of posts and telecommunications, beijing 100876, china State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China

The existing search engines are lack of the consideration of personalization and display the same search results for different users despite their differences in interesting and purpose. By analyzing user＇s dynamic search behavior, the paper introduces a new method of using a keyword query graph to express user＇s dynamic search behavior, and uses Bayesian network to construct the prior probability of keyword selection and the migration probability between keywords for each user. To reflect the dynamic changes of the user＇s preference, the paper introduces non-lineal gradual forgetting collaborative filtering strategy into the personalized search recommendation model. By calculating the similarity between each two users, the model can do the recommendation based on neighbors and be used to construct the personalized search engine.

关键词： search recommendation model search behavior expression keyword query graph gradual forgetting collaborative filtering

Analysis on Implementation of Asymmetric Regulation in china telecommunications Sector

在线全文

学校读者我要写书评

暂无评论

china Communications 2008年第3期5卷 104-107页

作者： Luo Mingwei beijing university of posts and telecommunications beijing Univ posts & Telecommun Beijing Peoples R China

Reference to the international cases and experiences of asymmetric regulation in telecommunications industry,based on china's legal environment and telecommunications competition in the market,give analysis to the role of asymmetric regulation for the development of china telecommunications market,put forward feasible measures to asymmetric regulation in china.

关键词： telecom asymmetric regulation china

Novel limited feedback scheme under the MIMO broadcast system

在线全文

学校读者我要写书评

暂无评论

The Journal of china Universities of posts and telecommunications 2009年第6期16卷 11-16页

作者： CHENG Tie-zheng,YUAN Chao-wei School of Information and Communication Engineering,beijing university of posts and telecommunications,beijing 100876,china School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

By deducing the distribution of the normalized channel covariance matrix,a novel limited feedback scheme is proposed under multiple users（MU） multiple-input multiple-output（MIMO） broadcast channel（BC） *** proposed scheme has advantages in three ***,it has no constraints on the number of users or ***,each user＇s feedback bits are independent of the number of receiving ***,the proposed scheme avoids the storage of large-size codebook on the *** results show that the performance of the proposed scheme is close to the perfect channel state information（CSI） case and it just needs a small number of feedback bits.

关键词： MIMO broadcast channel limited feedback normalized channel covariance

On the construction of multi-output Boolean functions with optimal algebraic immunity

在线全文

学校读者我要写书评

暂无评论

Science china(Information Sciences) 2012年第7期55卷 1617-1623页

作者： ZHANG Jie 1,2 ,SONG ShouChao 1 ,DU Jiao 2,3 & WEN QiaoYan 2 1 School of Science,beijing university of posts and telecommunications,beijing 100876,china 2 State Key Laboratory of Networking and Switching Technology,beijing university of posts and telecommunications,beijing 100876,china 3 Department of Mathematics,Xinxiang university,Xinxiang 453003,china School of Science Beijing University of Posts and Telecommunications Beijing China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing China Department of Mathematics Xinxiang University Xinxiang China

In this paper,we show a construction of multi-output Boolean functions with optimal algebraic ***,the relationship between the algebraic immunity of a multi-output Boolean function and those of its component functions is *** show that all the component functions,together with their nonzero linear combination,of the multi-output Boolean functions achieved by this construction have optimal algebraic immunity simultaneously.

关键词： algebraic immunity Boolean functions algebraic attacks annihilators

Soliton Propagation in Optical Fibers with Random Polarization Dispersion

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Lasers 1994年第1期B3卷 49-55页

作者： TANG Xiongyan YE Peida(Department of Radio Engineering,beijing university,of posts and telecommunications,beijing 100088, china) beijing Univ of posts and Telecommunications Beijing China

ＳｏｌｉｔｏｎＰｒｏｐａｇａｔｉｏｎｉｎＯｐｔｉｃａｌＦｉｂｅｒｓｗｉｔｈＲａｎｄｏｍＰｏｌａｒｉｚａｔｉｏｎＤｉｓｐｅｒｓｉｏｎ￥ＴＡＮＧＸｉｏｎｇｙａｎ；ＹＥＰｅｉｄａ（ＤｅｐａｒｔｍｅｎｔｏｆＲａｄｉｏＥｎｇｉ... 详细信息

ＳｏｌｉｔｏｎＰｒｏｐａｇａｔｉｏｎｉｎＯｐｔｉｃａｌＦｉｂｅｒｓｗｉｔｈＲａｎｄｏｍＰｏｌａｒｉｚａｔｉｏｎＤｉｓｐｅｒｓｉｏｎ￥ＴＡＮＧＸｉｏｎｇｙａｎ；ＹＥＰｅｉｄａ（ＤｅｐａｒｔｍｅｎｔｏｆＲａｄｉｏＥｎｇｉｎｅｅｒｉｎｇ，ＢｅｉｊｉｎｇＵｎ...

关键词： optical communication soliton transmission birefringent fiber polarization dispersion

Synchronization of MIMO OFDM systems by perfect complete generalized complementary orthogonal loosely synchronous code groups

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

The Journal of china Universities of posts and telecommunications 2009年第2期16卷 1-7页

作者： WANG Jian YANG Xun LI Dao-ben School of Information Engineering,beijing university of posts and telecommunications,beijing 100876,china School of Information Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

This article proposes a time/frequency synchronization algorithm in the multiple input multiple output （MIMO） systems, in which the perfect complete generalized complementary orthogonal loosely synchronous code groups are used as the synchronization sequence. The synchronization algorithm is divided into four stages： 1） synchronization in time domain by signal autocorrelation; 2） synchronization in frequency domain by fast Fourier transform （FFT）; 3） multipath dissociation using coherent detection and fine time synchronization; 4） fine frequency offset estimation by phase rotation. As per the perfect complete generalized complementary orthogonal loosely synchronous code groups, the cross-correlation and out-of-phase auto-correlation for any relative shift between any two codes is always zero. This ideal property makes the time/frequency synchronization algorithm simple and efficient. The simulation results show that even in the multipath fast fading channel with low signal noise ratio （SNR）, the MIMO system can get synchronized both in the time domain and frequency domain with high stability and reliability.

关键词： MIMO OFDM synchronization complementary orthogonal code loosely synchronous (LS) code

Secure network coding in the presence of eavesdroppers

在线全文

学校读者我要写书评

暂无评论

Science china(Information Sciences) 2010年第3期53卷 648-658页

作者： LUO MingXing1,2,3, YANG YiXian1,2,3, WANG LiCheng1,2,3 & NIU XinXin1,2,3 1Information Security Center, State Key Laboratory of Networking and Switching Technology, beijing university of posts and telecommunications, beijing 100876, china 2Key Laboratory of Network and Information Attack and Defence Technology of MOE, beijing university of posts and telecommunications, beijing 100876, china 3National Engineering Laboratory for Disaster Backup and Recovery, beijing university of posts and telecommunications, beijing 100876, china Information Security Center State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing China Key Laboratory of Network and Information Attack and Defence Technology of MOE Beijing University of Posts and Telecommunications Beijing China National Engineering Laboratory for Disaster Backup and Recovery Beijing University of Posts and Telecommunications Beijing China

Our concern, in the paper, is to construct information-theoretic secure network coding in the presence of eavesdroppers. Based on the generalized attack model and all-or-nothing transformation, the security of network coding in the generalized combination network can be characterized by the network capacity and the min-cut bound of wiretapping set from the source. Furthermore, it can be extended to any directed acyclic networks with single source. Compared with the traditional results, we construct information-theoretic secure network coding without additional encryptions and giving up any capacity.

关键词： all-or-nothing transformation secure network coding eavesdropping

Multi-function Device Based on Two Terahertz Optical Asymmetric Demutiplexers

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Lasers 1999年第5期8卷 3-5页

作者： HONG Xiaobin LIN Jintong(Optical Communication R & D Center, beijing university of posts and telecommunications, beijing 100876, china) 北京邮电大学光通信R&D中心北京 100876 北京邮电大学光通信R&D中心北京

A multi-function device based on two terahertz optical asymmeric demultiplexers (TOAD) is proposed, which can be used simultancously as demultiplexing, data regeneration,clock recovery and wavelength conversion unit. The device can work at an ultra-high speed optical time-division multiplexing (OTDM) system with relativey low speed components.

关键词： OTDM clock recovery phase-lock loop (PLL) terahertz optical asymmetric demultiplexer (TOAD) data regeneration wavelength conversion