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The Journal of china Universities of posts and telecommunications 2004年第4期11卷 48-53页

作者： MU Honga~1 WANG Ru-chuan~(1,2) WANG Hai-yan~11.Department of Computer Science and technology,Nanjing university of posts and telecommunications,Nanjing 210003,P.R.china 2.state key laboratory of Information Security(Graduate School of Chinese Aeademy of Sciences),beijing 100039,P.R.china Department of Computer Science and technology Nanjing University of Posts and Telecommunications Nanjing 210003

Security is an important issue for the widespread deployment of applications based on software agent *** is generally agreed that without the proper countermeasures in place,use of agent-based applications will be *** many projects have focused on the security issues of mobile agent and many mechanisms have been proposed tosolve the security *** paper discusses the security issues and the *** it points out some direc-tions for the research of the mobile agent security.

关键词： mobile agent mobile code security cryptography

A bio-inspired approach for cognitive radio networks

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Science Bulletin 2012年第Z2期 3723-3730页

作者： HE ZhiQiang *,NIU Kai,QIU Tao,SONG Tao,XU WenJun,GUO Li & LIN JiaRu key laboratory of Universal Wireless communications,Ministry of Education,beijing university of posts and telecommunications,beijing 100876,china

The recent increasing interest in cognitive radio networks has motivated the study and development of new approaches capable of coping with the intrinsic challenges of this kind of network,such as dynamic spectrum availability,distributed and heterogeneous network architectures,and soaring *** bio-inspired approaches,with appealing characteristics such as autonomy,adaptation and collective intelligence of collaborative individuals,have been extensively *** paper presents a comprehensive survey of bio-inspired approaches for cognitive radio networks,emphasizing their domains of ***,ant colony optimization and particle warm optimization are further investigated with examples and numerical simulation.

关键词： cognitive radio networks bio-inspired networking ant colony optimization particle swarm optimization

Mobile Ubiquitous Service Environment (4)

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ZTE communications 2007年第4期5卷 55-59页

作者： Zhang Ping,Ji Yang,Feng Zhiyong(Wireless technology Innovation institute,beijing university of posts and telecommunications,beijing 100876,china)

The Mobile Ubiquitous Service Environment(MUSE),established through the coordination and integration of mobile telecommunications and ubiquitous network,in the pursuit of Always Best Experience(ABE),represents the major development trend for the next generation mobile wireless *** on MUSE will involve the integration of the computing model system,service platform system,operating system and terminal structure system;and each involves exploration and innovation of a new networking structure,its control and management as well as its *** change in network resources triggers the change in network computing *** let readers have a basic understanding of MUSE,this lecture introduces MUSE in four *** section focuses on the MUSE network architecture and its key technologies.

关键词： Mobile Ubiquitous Service Environment ABE

Experimental Performance Evaluation of Mobile Sensor and Communication System Based on Ultraviolet

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Experimental Performance Evaluation of Mobile Sensor and Com...

Six-bit all-optical quantization using photonic crystal fiber with soliton self-frequency shift and pre-chirp spectral compression techniques

第24届中国控制与决策会议

作者： LI Cheng, ZHANG Min, CHEN Xue, LI Qing, LUO Pengfei, LIU Yile state key laboratory of Information Photonics and Optical communications, beijing university of posts and telecommunications, beijing, 100876

Presented in this paper is an experimental research on the mobile sensor and communication system based on transmitting with ultraviolet in either line-of-sight or non-line-of-sight conditions. The performance of this type of communication system is shown on the experimental platform which is set up. It proves the feasibility of ultraviolet communication system.

关键词： sensor and communication ultraviolet

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Chinese Physics B 2013年第11期22卷 345-349页

作者：康哲苑金辉李莎解松霖颜玢玢桑新柱余重秀 state key laboratory of Information Photonics and Optical communications Beijing University of Posts and Telecommunications

In this paper, we propose an optical quantization scheme for all-optical analog-to-digital conversion that facilitates photonics integration. A segment of 10-m photonic crystal fiber with a high nonlinear coefficient of 62.8 W-1/kin is utilized to realize large scale soliton self-frequency shift relevant to the power of the sampled optical signal. Furthermore, a 100-m dispersion-increasing fiber is used as the spectral compression module for further resolution enhancement. Simulation results show that 317-nm maximum wavelength shift is realized with 1550-nm initial wavelength and 6-bit quantization resolution is obtained with a subsequent spectral compression process.

关键词： all-optical analog-to-digital conversion photonic crystal fiber soliton self-frequency shift spectralcompression

Design and analysis of Optical-Communication-Band Sub-wavelength Grating Polarizer

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Design and analysis of Optical-Communication-Band Sub-wavele...

中国遗传学会“第十一届全国激光生物学学术会议”暨《激光生物学报》创刊廿周年庆祝会、第十届粤港生物物理研讨会暨2012年广东生物物理学术年会

作者： Erfei Cai,Yongqing Huang~*,Xiaofeng Duan,Tingting Wang,Xiaomin Ren (state key laboratory of Information Photonics and Optical communications,beijing university of posts and telecommunications,beijing 100876)

The sub-wavelength grating has special characteristics compared to traditional *** to the requirement of the optical communication devices,sub-wavelength grating polarizer was designed based on rigorous coupled-wave theory(RCWA).The paper analyzes the grating parameters such as the period,depth,fill grove that influence the diffraction efficiency of the grating. Calculation results indicate that the diffraction efficiency of sub-wavelength grating changes with the period,the depth of the grove,fill factor,and shape of the grating. The TM mode diffraction efficiency is more than 95%,and the TE mode diffraction efficiency is less than 5%,the pyramidal sub-wavelength polarizer grating has good performance than others shapes in the optical communication band of *** this paper,we designed this kind of sub-wavelength grating polarizer has great potential applying in optical switching,optical memory,optical detectors and other photo-electronic devices.

关键词： Design and analysis of Optical-Communication-Band Sub-wavelength Grating Polarizer

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组件模型(CCM)的多视点分析

计算机工程与应用 2003年第36期39卷 9-14,54页

作者：龙湘明杨放春苏森北京邮电大学交换技术与通信网国家重点实验室北京100876

中间件与组件相结合正成为分布式系统开发的一个主要方向。CORBA是一个主流的中间件,最新的CORBA3.0规范增加CORBA组件模型(CCM),完成了CORBA向“组件化”转化的目标。文章分析了CCM产生的原因和背景,并运用IEEEStd1471多视点的分析方法... 详细信息

中间件与组件相结合正成为分布式系统开发的一个主要方向。CORBA是一个主流的中间件,最新的CORBA3.0规范增加CORBA组件模型(CCM),完成了CORBA向“组件化”转化的目标。文章分析了CCM产生的原因和背景,并运用IEEEStd1471多视点的分析方法,较全面的从各个视点剖析了CORBA组件模型,并给出了CCM的一个完整的多视点视图和基于CORBA组件的软件开发过程。最后指出了CCM需要进一步研究和完善的地方。

关键词：组件模型 CORBA 面向对象软件组织软件复用软件系统软件开发

Highly sensitive digital optical sensor with large measurement range based on the dual-microring resonator with waveguide-coupled feedback

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Chinese Physics B 2014年第3期23卷 284-288页

作者：向星烨王葵如苑金辉晋博源桑新柱余重秀 state key laboratory of Information Photonics and Optical communications Beijing University of Posts and Telecommunications

We propose a novel high-performance digital optical sensor based on the Mach-Zehnder interferential effect and the dual-microring resonators with the waveguide-coupled feedback. The simulation results show that the sensitivity of the sensor can be orders of magnitude higher than that of aconventional sensor, and high quality factor is not critical in it. Moreover, by optimizing the length of the feedback waveguide to be equal to the perimeter of the ring, the measurement range of the proposed sensor is twice as much as that of the conventional sensor in the weak coupling case.

关键词： optical sensor microring resonator high sensitivity large measurement range

Ranking Potential Reply-Providers in Community Question Answering System

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china communications 2013年第10期10卷 125-136页

作者：韩闻文阙喜戎宋思奇田野王文东 state key laboratory of networking and switching technology Beijing University of Posts and Telecommunications

Community Question Answering （CQA） websites have greatly facilitated users＇ lives, with an increasing number of people seeking help and exchanging ideas on the Internet. This newlymerged community features two characteristics： social relations and an ask-reply mechanism. As users＇ behaviours and social statuses play a more important role in CQA services than traditional answer retrieving websites, researchers＇ concerns have shifted from the need to passively find existing answers to actively seeking potential reply providers that may give answers in the near future. We analyse datasets derived from an online CQA system named ＂Quora＂, and observed that compared with traditional question answering services, users tend to contribute replies rather than questions for help in the CQA system. Inspired by the findings, we seek ways to evaluate the users＇ ability to offer prompt and reliable help, taking into account activity, authority and social reputation char- acteristics. We propose a hybrid method that is based on a Question-User network and social network using optimised PageRank algorithm. Experimental results show the efficiency of the proposed method for ranking potential answer-providers.

关键词： CQA user behaviour analysis question-user network social network PageRank activity estimation authority estimation