高效、高质量的纸质工程图和资料存档方案

一、传统保存方案的缺陷 传统的工程图样和资料的保存归档形式是通过纸质或胶片的形式进行的,很多企业都用专门的仓库保管这些珍贵的技术资料.这些资料的内容相当广泛,包括机械设计、建筑设计、工程设计、测绘及地图等各行业的信息.资料的介质也有不同的分类,包括硫酸纸、纸质蓝图、白图及胶片等.     

一种基于XML的个性化的资源需求描述机制

在基于因特网的教育资源网格体系结构和服务理论研究中,提出了教育资源网格中一种基于XML的个性化文件资源需求描述机制.需求者不仅可以更加准确地表达自己对各类文件资源的需求,还可以指明自己所期望的资源的区域和学校的来源.并且对备选的信息进行优先级的排序,在搜索的过程中按照优先级的顺序对搜索的结果进行优化.解决了资源需求描述机制中对教育资源网格的文件资源需求描述支持较少的问题.     

"超越"的价值--记ANSYS CHINA 2003年巡展活动

美国ANSYS公司是一家颇富传奇色彩的公司.1970年,当时还是匹兹堡大学力学教授的史沃森博士凭借一腔热忱和1282美元的资金,带领几个员工白手起家,创立了ANSYS公司.经过30多年的风雨和数代人的努力,ANSYS从一家名不见经传的私人小公司迅猛发展成为今天CAE领域的龙头企业,其依靠的就是对技术的无限追求和对市场的敏锐感觉.     

基于Visual Basic的自动化测试系统的研究与设计

讨论了一种新的测试思想,不需要使用专用的脚本语言,自己定义简单的测试脚本格式,用VB来解释自己定义的脚本.研究了这种思想的实现方法和与硬件电路相关的基于VB的串口、并口的通信.开发出了实际使用的自动测试软件,大大加快了测试速度,提高了测试的自动化程度.     

基于XML的开放式WebGIS的系统设计

基于XML的开放式WebGIS的系统设计是解决传统WebGIS数据共享、服务互操作问题的好方法.本文分析了基于XML的开放式WebGIS系统的设计目标,提出了一个基于XML技术的WebGIS系统设计方案.     

计算机网络信息安全面临的问题和对策

计算机的广泛应用把人类带入了一个全新的时代,特别是计算机网络的社会化,已经成为了信息时代的主要推动力.目前,全世界的军事、经济、社会、文化各个方面都越来越依赖于计算机网络,人类社会对计算机的依赖程度达到了空前的纪录.由于计算机网络的脆弱性,这种高度的依赖性使国家的经济和国防安全变得十分脆弱,一旦计算机网络受到攻击而不能正常工作,甚至瘫痪,整个社会就会陷入危机.     

基于服务组合的柔性流程建模

在分析现有柔性流程建模方法的基础上,总结柔性流程建模的实现途径.在面向角色的柔性流程建模方法中采用角色类的划分和角色的动态选取和配置,简化流程的构造.同时提出将Agent技术和Services相结合,设计一种面向角色服务的、封装的、分层的和去耦合的建模系统,并讨论了基于服务组合的柔性流程建模的实现方案.     

一个基于智能的MAS模型及其方法论

为了得到好的体系结构模式来将模式驱动的方法用于多智能体系统(MAS)的设计,必须有形式上抽象但是技术上细化的方法论.基于智能思想的提出,使得以智能作桥梁将AO,PO和OO的优点融合,并以此提出一种覆盖了从事务分析到Agent组织系统实现全过程而又比较技术化的方法论IB.同时提出一个基于智能的智能系统模型(MIBIS),通过模型的构造过程来叙述方法论.因为模型以及构造过程的形式化和整个过程的技术化,所以使得该模型和方法论能够被用于体系结构模式的归纳,也能用于工程的实用.而且该模型所表达的结构有良好动态组织性、实用性、实时性、扩展性和重用性.     

家庭精灵华硕精致迷你PC独领群雄

以计算机担当信号源和控制所实现的家庭影院方式,因其灵活、方便而受到了越来越多家庭用户的青睐。也正因如此,作为主打客厅数字高清娱乐平台的HTPC,以其强大的处理能力、灵活的配置和优质的画面输出等诸多优势而成为家庭用户在选购电脑时的首选。随着1080P显示设备的大量普及,以往动辄数万的家庭影院设备对于普通家庭亦变得触手可及,HTPC亦在此间作为新兴的客厅文化而广受追求生活品质的时尚达人们的热捧。     

Ajax技术及其应用研究

Web应用所提供的体验和用户从桌面应用程序所得到的体验在响应速度、易用性等方面存在着巨大的差距,为了改善Web应用程序给用户带来的体验,IT界引出了Ajax这个新名词.文章简要介绍了Web 2.0的Ajax技术的基础理论,就其关键技术中的XMLHttpRequest对象作了重点分析,并对Ajax技术的优缺点及其应用作了探讨,展示了Ajax所以能给用户带来更为强大的Web体验的实质.     

Meme Media for Clipping and Combining Web Resources

The publication and reuse of intellectual resources using the Web technologies provide no support for us to clip out any portion of Web pages, to combine them together for their local reuse, nor to publish the newly composed object as a new Web page for its reuse by other people. This paper shows how the meme-media architecture is applied to the Web to provide such support for us. This makes the Web work as a shared repository not only for publishing intellectual resources, but also for their collaborative reediting. We will propose a general framework for clipping arbitrary Web contents as live objects, for defining IO ports on such a clip, and for the recombination and linkage of such clips based on both the original and some user-defined relationships among them. In our previous works, we proposed two separate frameworks for these three purposes; one works for the first two, and the other for the last. Here we will propose a unified framework for these three purposes, as well as its detailed internal mechanisms. Then we show how it can be easily applied to various legacy Web applications to develop innovative services.     

Estimating the Attraction Domain for the Boost Inverter

This work presents an approach for estimating the domain of attraction for polynomial systems with state and control‐signal constraints, including saturation. In many problems, it is possible to derive global stability properties for such systems, neglecting constraints. Consideration of the constraints usually makes the problem much more complicated. In this paper, the stability analysis performed for the unconstrained case is used for the problem as a whole. For application of the method, there are powerful computational tools that can be employed in cases of polynomial systems. The technique is not only valid for the analysis of equilibrium points, but also for other attractors, such as limit cycles. As examples, the domain of attraction for given control laws is estimated for both a nonlinear DC‐DC boost converter and for a boost inverter.     

A Probabilistic Analysis of Multiple-drug Testing Procedures in Sports Doping Control

Athletes engaged in competition, particularly those involved in international competitions such as the Olympics, are increasingly being tested for a greater variety of banned substances; it is not unusual for tests to be conducted for 100 drugs and another 400 as metabolites. Previous studies related to the accuracy of drug testing processes have failed to properly consider the effects of testing for more than one drug. In order to identify appropriate indicators for the multiple-drug case, probability theory and accuracy concepts applicable to testing for multiple drugs are developed and applied to illustrative data. The probability that a drug-free individual will test positive for drug use is shown to be much higher than indicated by previous studies, and it is shown that an increase in the number of drugs tested for yields an approximately proportionate increase in the probability that a positive test result is erroneous. Therefore, while testing for one drug may result in a comfortably low rate of false accusations of drug use, testing for multiple drugs may well result in an unacceptably high rate. Finally, a set of empirical measures is suggested for use in cases of tests for multiple drugs; the measures will provide for comparability among laboratory proficiency studies.     

基于约束的XML文档规范化算法

XML模式设计是XML数据库设计的关键．基于XML文档的基本概念给出了XML部分函数依赖、传递函数依赖、XML范式、XML第1到第3范式以及DTD无损联接分解的相关定义,提出XML模式规范化转换规则,给出无损联接分解的两种规范化算法,对算法的正确性、可终止性和时间复杂性进行了证明分析,并实验证明了规范化后的文档查询和存储效率有明显的提高．这将对未来的XML函数依赖保持、XML多值依赖以及XML模式设计的进一步规范化研究奠定理论基础．     

Rapid Communication. Exposure assessment of biomechanical stress in repetitive manual work using frequency-weighted filters

A quantitative exposure assessment strategy for physical stress associated with repetitive manual tasks is proposed using continuous biomechanical data measured directly from electrogoniometers or force sensors. This paper describes an efficient method for reducing large quantities of biomechanical data into a quantifiable metric that accounts for recognized musculoskeletal exposure factors, including repetitiveness, postural or forceful exertion stress, and duration. A frequency domain approach is used for averaging elemental data recorded for repetitive cycles. Parameters for frequency-weighted filters are developed using psychophysical data for equivalent discomfort levels resulting from repetitive movements of different amplitudes and frequencies. These filters enable continuous biomechanical data to be filtered and integrated, resulting in a single quantity corresponding to psychophysical response characteristics for repetitive motion stress. It is anticipated that a similar approach may be used for epidemiological response characteristics. Applications of this theory may make it possible for assessing exposure to physical stress in a manner analogous to the way in which sound level meters are used for measuring exposure to acoustic noise. Repetitive wrist flexion and localized discomfort was used for demonstrating the feasibility of this approach. Suitable data reduction techniques are necessary for evaluating work methods, job designs, and for conducting large scale detailed epidemiological investigations of cumulative trauma disorder risk factors. Frequency-weighted filters based on human response to physical stress at different frequencies can greatly simplify exposure analysis and ultimately may make it possible for quantitative exposure limits to be established.     

Characterization of reconfigurable Stewart platform for contour generation

The limited treatment available for Stewart platform characteristics leads to the lack of an efficient methodology for determining the optimum geometry for different tasks. In this paper, an effort is made to characterize the parameters for developing a reconfigurable Stewart platform for the contour generation application. A solution is provided through the formulation of dimensionless parameters in combination with a study on the generic parameters like configuration. The variable geometry approach for the reconfiguration of Stewart platform has been adopted for four different platforms, and a generic approach is formulated after studying different parameters. A stiffness model developed for contour generation application is used in tandem with this generic approach to identify the trajectory with maximum stiffness for complex contours. The proposed methodology provides a holistic approach to develop a complete set of design tool to choose the optimum geometry for any new reconfigurable Stewart platform to be developed.     

A stress-strength interference model for predicting CTD probabilities

A model for predicting the incidence rate of carpal tunnel syndrome (CTS) for a given job, was developed using known biomechanical data, mechanical properties of human tendons and reliability engineering techniques to simplify the problem. In addition, time-dependent stress-strength interference theory was used to quantify the stress on the tendons during a job cycle, based on wrist position and grip strength and to estimate the tendon failure rate (or CTS incidence) for a given job. Higher failure probabilities were predicted for greater wrist deviations, for higher grasp forces, for females as compared to males, for wrist extension as compared to wrist flexion, and for two-fingered pinches as compared to four-fingered grasps. The predictions closely matched previously reported CTS incidence rates for a poultry thigh boning task.     

The most economic setting for a uniformly shifting process

A method for finding the optimal setting for a uniformly-shifting process mean is developed and an algorithm for solution (suitable for microcomputer implementation) is presented. A determination of the number of parts to be made before resetting, and the level to which the process is to be reset is made given costs for improperly sized parts and for process resetting.     

Creating names for retrieval by self and others

Two experiments aimed to explore the general usability of filenames that were either chosen for personal use or designed for another user, within a document-filing scenario. Both experiments revealed a strong benefit for using self-chosen names over using names that were chosen by another for their personal use. However, both experiments also showed that participants could to some extent adapt their chosen names for use by a wider population. In experiment one, users could recall these ‘designed’ names more accurately than names that had been chosen for personal use by another (although this difference was not evident in a recognition test). Experiment two supported this effect; names designed for general use were more accurately recalled by another than the names designed for self-use after two sessions of use. Names designed for general use employed higher frequency words than did the self-chosen names, which supports the view that the benefit for self-chosen names partly lies in their exploitation of idiosyncratic associations.     

A dynamic workflow framework for mass customization using web service and autonomous agent techniques

Custom software development and maintenance is one of the key expenses associated with developing automated systems for mass customization. This paper presents a method for reducing the risk associated with this expense by developing a flexible environment for determining and executing dynamic workflow paths. Strategies for developing an autonomous agent-based framework and for identifying and creating web services for specific process tasks are presented. The proposed methods are outlined in two different case studies to illustrate the approach for both a generic process with complex workflow paths and a more specific sequential engineering process.