基于模型驱动的安全访问控制的研究

随着计算机应用到各个领域的广度、深度不断扩大,软件的安全需求变得越来越复杂.然而开发人员对系统进行建模时一般不考虑安全需求,系统安全策略和安全机制往往是开发人员在系统开发后期对系统的补充和措施的完善.由此提出将访问控制需求集成到软件开发过程的分析阶段,将访问控制策略建模与功能需求建模集成.通过模型驱动方法为功能需求模型相关的安全方面提供模型,研究从功能模型产生安全模型,最终形成安全访问控制策略.     

Lotus Domino／Notes的访问控制

信息系统的访问控制关系到整个系统的信息安全。Lotus Domino/Notes群件系统提供先进可靠的安全机制,特别在访问控制方面,与传统的基于关系型数据库的系统相比具有许多独特的控制方法。简单描述了Lotus Domino/Notes的访问控制抽象模型以及影响访问控制的策略因素,再从较高到较低的级别,逐步地分析了从应用系统级、数据库级、大纲级、文档级、域级等不同层次的访问控制方式。Lotus Domino/Notes提供的这些对信息资源的访问控制方法,能够为企业的信息系统提供比较全面而安全的访问控制解决访问。     

统一应用安全平台的设计及应用

提出了基于PKI／PMI的统一应用安全平台的设计思想，由访问控制、数据验证、安全审计等安全服务组件构成，实现了应用系统的强身份认证、访问控制、数据验证、安全审计等安全服务机制。最后描述了统一应用安全平台在B／S和C／S模式应用系统中的应用。     

整合分级的角色访问控制系统的研究与设计

基于角色的访问控制是当前先进的安全管理方法,考虑到该方法在描述资源访问属性时的不足,本文提出了把分级思想整合到基于角色的访问控制当中,使用分级服务来描述所保护资源的权限属性,并探讨了整个系统的方案设计,以及该设计方案的特点。     

一种基于属性证书和角色的访问控制模型

基于角色的访问控制是安全系统中保护资源的有效手段之一.基于对面向对象RBAC模型的分析,引入PMI属性证书,提出一种面向对象的访问控制模型AC-ORBAC,给出形式化描述,该模型通过属性证书实现角色授权访问控制,使访问控制的管理更为灵活,对职责分离进行了讨论.同时结合PKI实现了一种面向对象的基于角色和属性证书的访问控制方法.     

面向多级安全的结构化文档描述模型

面向多要素访问控制和多级安全需求,为了解决网络环境的开放性、多样化所带来的安全问题,基于现有的结构化文档描述模型及访问控制模型,提出了一种面向多级安全的结构化文档描述模型和描述方法,并给出安全属性的描述结构及其对应的可扩展标识语言（XML）实例,最后对提出的模型进行了安全性分析。     

基于中间件技术的分布式应用系统中访问控制的研究

在分布式应用系统中,利用中间件技术的访问控制,目的是限制计算机系统的合法用户所能进行的操作.文章首先对现有的.NET安全、Java安全平台、CORBA安全服务等中间件技术的访问控制现状进行描述和比较,随后介绍了三个重要的研究方向,讨论它们的应用前景,并分析研究热点和发展趋势.     

基于角色访问控制的移动代理安全系统的UML建模

鉴于移动代理的安全机制，文中用统一建模语言(UML)描述了基于角色的访问控制安全模式基于角色的访问控制(RBAC)和移动代理系统的系统结构，利用RBAC控制代理对代理平台资源的访问，得出了若干结论。     

基于移动Agent的Web服务安全访问机制研究

针对web服务安全问题中的访问控制,提出将移动Agent引入web服务的安全访问控制模型,通过SRP协议对web服务附加了一个独立的访问控制代理层,具有良好的通用性.实现了基于移动Agent的web服务访问控制模型,并对控制流程进行了描述.     

基于移动Agent的Webj服务安全访问机制研究

针对Web服务安全问题中的访问控制，提出将移动Agent引入Web服务的安全访问控制模型，通过SRP协议对Web服务附加了一个独立的访问控制代理层，具有良好的通用性。实现了基于移动Agent的Web服务访问控制模型．并对控制流程进行了描述。     

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.     

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.     

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.     

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.     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal （200） （2d = 0.4027 nm） is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line（w）, the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line（x）, the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines（y）, the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line（z） in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line（q） in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution（λ/△ 2） is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.     

Electronic Structure of Semiconductor Nanocrystals

This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.     

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.     

Critical Stage Rule-Based Real Time Dispatch（RTD）System in Highly-Mixed-Products （HMP） FAB

An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.     

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.