移动Agent系统安全技术研究

移动Agent作为新一代网络分布处理技术，能在网路上任意移动，自动执行使用者所设计和赋予的工作任务。移动Agent的安全问题是该项技术能否成功应用的关键。对移动Agent可能存在的安全问题以及遭受的攻击类型作了较详细的论述。从检测和保护两方面来阐述目前解决移动Agent安全问题的方法以及存在的问题。最后，引入具有监控和授权功能的安全管理器，提出了一种新的移动Agent系统安全模型，并分析了该模型的整个工作流程。     

可信移动Agent的研究及在分布式网络管理中的应用

为解决分布式网络管理的安全问题,利用移动Agent框架作为底层平台,应用VMC概念将移动Agent和SNMPAgent相融合,构建一种基于可信移动Agent的安全体系结构。实验结果表明,采用此体系结构的网络管理系统能够确保移动Agent的可信性。因此,该体系结构在受到Agent到Agent平台或Agent到Agent攻击情况下的安全性得到评估,证明在网络管理任务中其性能是可信的。     

移动Agent安全性分析

在简要介绍移动Agent技术和它可能面临的各种安全问题之后,提出了目前相应的安全措施,并介绍了国内外几种典型的移动Agent系统的安全解决方案,提出了一项自主开发的基于Java和CORBA的移动Agent平台（Roamer）系统的安全设计方案。     

关于改善移动Agent系统安全性的探讨

移动Agent系统面临的首要问题是安全性,它需要一个涉及多种策略和机制的安全框架来保护Agent平台及移动Agent本身免受恶意的攻击。当前大部分研究都是围绕典型的安全威胁而提出的特殊的安全技术。本文探讨一种将安全性与Agent平台融为一体的框架,这个框架可根据实际移动Agent应用系统的需要,灵活动态地提供不同质量的安全服务。     

关于改善移动Agent系统安全性的探讨

移动Agent系统面临的首要问题是安全的，它需要一个涉及多种策略和机制的安全框架来保护Agent平台及移动Agent本身免受恶意的攻击，当前大部分研究都是围绕典型的安全威胁而提出的特殊的安全技术。本探讨一种将安全性与Agent平台融为一体的框架，这个框架可根据实际移动Agent应用系统的需要，灵活动态地提供不同质量的安全服务。     

改进的基于层次化身份加密的移动Agent安全方案

移动Agent的安全性是限制其广泛应用的一个重要因素。论文提出了一种改进的基于层次化身份加密的移动Agent安全方案,更简单、高效地实现了分布式环境下移动Agent与主机的相互认证,同时实现了对移动Agent的路径追踪,为移动Agent系统提供了可靠的安全性和稳健性保证,具有较高的实用价值。     

Agent平台信任机制研究

随着网络和计算机技术的迅猛发展,信任管理技术已经成为支撑基于Internet的电子商务、分布式应用、系统安全的关键性技术之一,尤其是在移动Agent的平台保护中的应用.文中将对Agent实体的信任机制从定义、关系、性质等方面进行研究,提出了保护Agent实体的两个模型,即:Agent平台与Agent之间的和Agent平台保护模型和Agent平台之间的Agent平台保护模型.     

基于移动Agent的网格资源监控模型

给出了资源描述定义,并构建了一种基于移动Agent的网格资源监控模型MAGM,模型中的三类移动Agent可以完成对网格资源信息的收集、注册和管理;同时给出了一种各类Agent负载均衡协作算法.在实验室环境中构建了基干Globus和IBM的Aglet的网格实验平台,并进行了仿真实验.     

利用移动Agent实现对远程数据库的访问

介绍了移动Agent的概念和特点，并在一个移动Agent平台Aglet之上进行二次开发，利用移动Agent访问远程数据库。给出了移动Agent访问远程数据库的模型，并进行了具体实现。     

一种新型的网格资源监控模型的研究与设计

为了实时准确监控网格中的资源情况,本文研究并引入移动Agent技术,建立了基于移动Agent技术的网格资源监控模型MAGM(Mobile Agent Grid Monitor),提出了解决LBA组件内各类Agent负载均衡协作问题的算法.在基于Globus和IBM的Aglet的网格实验平台上进行的仿真实验,结果表明MAGM模型的有效性.     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers

A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.     

A rigorous proof of MIMO channel capacity’s increase with antenna number

It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output（MIMO） communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.     

Call for Papers

正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks