Gnomon 分布式密码计算环境设计与实现

随着网络技术和信息技术的飞速发展，互联网环境下的安全问题越来越受到 政府、军事和商业部门的重视。密码技术是信息安全的核心技术，密码算法的设 计和实现一直是信息安全学界的重要研究内容。近年来，随着计算技术和网络的 飞速发展，计算工具和模式发生了变化，出现了分布式计算、网格计算和云计算 等新技术。在国内外已经分别采取过大型机、并行计算和分布式计算等方式来提 高密码计算的速度。采用新技术来设计和实现新的密码计算平台，对密码算法的 设计、分析以及应用有重要意义。分布式计算和网格计算在信息安全领域中的应 用是本文的主要研究内容。 首先，通过分析密码计算和网格计算的特点，确定了本文的研究目标，即构 建一个通用的、高效的、可扩展的、可移植的分布式计算环境。其次，分析研究 目标的特点以及遇到的问题，详细讨论系统所采用解决方案的特点及优势。在系 统分析设计的基础上，基于Globus Toolkit 和SWT/JFace 工具包，对Gnomon 分 布式密码计算环境进行了实现，并详细介绍了各个模块的功能。最后，设计和实 现了两个问题实例：大整数因子分解和Rainbow 攻击。针对问题实例，进行了多 组实验，并给出了相应的实验结果和分析。 Gnomon 分布式计算环境为密码的分布式计算提供支持，其易用性和可扩展 性为密码分析和设计人员带来了方便。本文研究成果推动了分布式密码计算的研 究与发展。

Gnomon分布式密码计算环境设计与实现

随着网络技术和信息技术的飞速发展，互联网环境下的安全问题越来越受到政府、军事和商业部门的重视。密码技术是信息安全的核心技术，密码算法的设计和实现一直是信息安全学界的重要研究内容。近年来，随着计算技术和网络的飞速发展，计算工具和模式发生了变化，出现了分布式计算、网格计算和云计算等新技术。在国内外已经分别采取过大型机、并行计算和分布式计算等方式来提高密码计算的速度。采用新技术来设计和实现新的密码计算平台，对密码算法的设计、分析以及应用有重要意义。分布式计算和网格计算在信息安全领域中的应用是本文的主要研究内容。 首先，通过分析密码计算和网格计算的特点，确定了本文的研究目标，即构建一个通用的、高效的、可扩展的、可移植的分布式计算环境。其次，分析研究目标的特点以及遇到的问题，详细讨论系统所采用解决方案的特点及优势。在系统分析设计的基础上，基于Globus Toolkit和SWT/JFace工具包，对Gnomon分布式密码计算环境进行了实现，并详细介绍了各个模块的功能。最后，设计和实现了两个问题实例：大整数因子分解和Rainbow攻击。针对问题实例，进行了多组实验，并给出了相应的实验结果和分析。 Gnomon分布式计算环境为密码的分布式计算提供支持，其易用性和可扩展性为密码分析和设计人员带来了方便。本文研究成果推动了分布式密码计算的研究与发展。

Magnetic field design for floating zone crystal growth

The magnetic fields produced by electrical coils are designed for P-doped Si crystal growth in a floating full zone in microgravity environment. The fields are designed specially to reduce the how near the free surface and then in the melt zone by adjusting the coil positions near the melt zone. The effects of the designed magnetic fields on reducing the Row velocity and the non-uniformity of the concentration distribution in the melt zone are better than those of the case of a uniform longitudinal magnetic field, obtained by numerical simulation. It is expected to improve the radial macro-segregation and reduce the convection in the crystal growth at the same time by using the designed magnetic field.

Materials selection in mechanical design for microsensors and microactuators

Microsensors and microactuators are vital organs of microelectromechanical systems (MEMS), forming the interfaces between controller and environment. They are usually used for devices ranging in size at sub-millimeter or micrometer level, transforming energy between two or more domains. Presently, most of the materials used in MEMS devices belong to the silicon material system, which is the basis of the integrated circuit industry. However, new techniques are being explored and developed, and the opportunities for MEMS materials selection are getting broader. The present paper tries to apply 'performance index' to select the material best suited to a given application, in the early stage of MEMS design. The selection is based on matching performance characteristics to the requirements. A series of performance indices are given to allow a wide range comparison of materials for several typical sensing and actuating structures, and a rapid identification of candidates for a given task. (C) 2002 Elsevier Science Ltd. All rights reserved.

Experimental Research On Fatigue Property Of Steel Rubber Vibration Isolator For Offshore Jacket Platform In Cold Environment

Jacket platform is the most widely used offshore platform. Steel rubber vibration isolator and damping isolation system are often used to reduce or isolate the ice-induced and seismic-induced vibrations. The previous experimental and theoretical studies concern mostly with dynamic properties, vibration isolation schemes and vibration-reduction effectiveness analysis. In this paper, the experiments on steel rubber vibration isolator were carried out to investigate the compressive properties and fatigue properties in different low temperature conditions. The results may provide some guidelines for design of steel rubber vibration isolator for offshore platform in a cold environment, and for maintenance and replacement of steel rubber vibration isolator, and also for fatigue life assessment of the steel rubber vibration isolator. (C) 2009 Elsevier Ltd. All rights reserved.

Intense upconversion luminescence and effect of local environment for Tm3+/Yb3+ co-doped novel TeO2-BiCl3 glass system

We present the results of a study that uses theoretical and experimental methods to investigate the characteristics of the upconversion luminescence of Tm3+/Yb3+ codoped TeO2-BiCl3 glass system as a function of the BiCl3 fraction. These glasses are potentially important in the design of upconversion fiber lasers. Effect of local environment around Tm3+ on upconversion fluorescence intensity was analyzed by theoretical calculations. The structure and spectroscopic properties were investigated in the experiments by measuring the Raman spectra, IR transmission spectra, and absorption and fluorescence intensities at room temperature. The results indicate that blue luminescence quantum efficiency increases with increasing BiCl3 content from 10 to 60 mol%, which were interpreted by the increase of asymmetry of glass structure, decrease of phonon energy and removing of OH- groups. (c) 2005 Elsevier B.V. All rights reserved.

Design and path planning for a remote-brained service robot

This paper presents a novel robot named "TUT03-A" with expert systems, speech interaction, vision systems etc. based on remote-brained approach. The robot is designed to have the brain and body separated. There is a cerebellum in the body. The brain with the expert systems is in charge of decision and the cerebellum control motion of the body. The brain-body. interface has many kinds of structure. It enables a brain to control one or more cerebellums. The brain controls all modules in the system and coordinates their work. The framework of the robot allows us to carry out different kinds of robotics research in an environment that can be shared and inherited over generations. Then we discuss the path planning method for the robot based on ant colony algorithm. The mathematical model is established and the algorithm is achieved with the Starlogo simulating environment. The simulation result shows that it has strong robustness and eligible pathfinding efficiency.

Design and path planning for a remote-brained service robot

This article introduced an effective design method of robot called remote-brain, which is made the brain and body separated. It leaves the brain in the mother environment, by which we mean the environment in which the brain's software is developed, and talks with its body by wireless links. It also presents a real robot TUT06-B based on this method which has human-machine interaction, vision systems, manipulator etc. Then it discussed the path planning method for the robot based on ant colony algorithm in details, especially the Ant-cycle model. And it also analyzed the parameter of the algorithm which can affect the convergence. Finally, it gives the program flow chat of this algorithm.