A formal description of open distributed processing (ODP) trading based on guidelines for the definition of managed objects (GDMO)

New requirements of growing computer networks and information systems have an influence on extended client/server models with increased functionality. This forms the basis for service management in distributed systems which is realized by a service trading concept. This paper studies the requirements derived from the Open Distributed Processing (ODP) Reference Model in order to consider an open service market. Furthermore, it examines management possibilities for describing the service trading scenario. Because of similar architectures and properties ODP services, service offers, types, exporters and traders are mapped onto management components and modeled as managed objects. Therefore, the Guidelines for the Definition of Managed Objects (GDMO) are used. The final concept allows a precise and unambiguous study of the service trading scenario and provides means for exporting and importing of service offers in a distributed environment.     

PowerPoint2000动画设计应用

PowerPoint2000是Microsoft公司办公自动化软件Office2000的重要构件之一。其自身具有强大的处理功能，尤其是PowerPoint2000所提供的基本动画效果，更是给演示文稿增添了很多色彩。如果能将这些基本动画效果巧妙地组合在一起，就会创作出更富感染力的作品。就创作中的技巧并结合应用举例分析如下。相信人们可以利用这些设计思想，创作出更加精彩的作品。     

Environment as a first class abstraction in multiagent systems

The current practice in multiagent systems typically associates the environment with resources that are external to agents and their communication infrastructure. Advanced uses of the environment include infrastructures for indirect coordination, such as digital pheromones, or support for governed interaction in electronic institutions. Yet, in general, the notion of environment is not well defined. Functionalities of the environment are often dealt with implicitly or in an ad hoc manner. This is not only poor engineering practice, it also hinders engineers to exploit the full potential of the environment in multiagent systems. In this paper, we put forward the environment as an explicit part of multiagent systems.We give a definition stating that the environment in a multiagent system is a first-class abstraction with dual roles: (1) the environment provides the surrounding conditions for agents to exist, which implies that the environment is an essential part of every multiagent system, and (2) the environment provides an exploitable design abstraction for building multiagent system applications. We discuss the responsibilities of such an environment in multiagent systems and we present a reference model for the environment that can serve as a basis for environment engineering. To illustrate the power of the environment as a design abstraction, we show how the environment is successfully exploited in a real world application. Considering the environment as a first-class abstraction in multiagent systems opens up new horizons for research and development in multiagent systems.     

基于IPV6的源地址验证整体架构的物联网分布式源地址验证

IPv6作为下一代物联网IP层技术,进一步扩大了地址空间,并在国家政策的号召以及国家电网公司的积极响应下在电力、石油等方面获得了广泛的应用,为智能电网与下一代互联网的深度融合探索道路、提供经验。但是其应用中仍然存在较多重大的问题,其中最为突出的就是其安全性和真实性。当前的网络体系结构,大多数情况下并不检查源地址,这就导致源地址伪造事件很容易发生。本文主要分析了物联网对IPv6的需求,总结了多种IPv6源地址验证方案,并重点对SAVS框架下的IPv6源地址验证方案进行分析和探讨。     

为官不为:界定、根源及治理

"为官不为"可以分为能力缺失型、享乐散漫型、环绕推挡型、名利偏好型、被动应激型和闻风观望型. 管理体制、行政机制、传统文化等方面存在的某些不良因子促成了为官不为现象."为官不为"的实质是公务员的主体性缺位. 治理"为官不为"现象必须强化公务员的个体素质,优化行政机制,正确理解传统文化,实现综合治理.     

Use and non‐use of VDTs—organization of terminal work: Research findings from Swedish cross‐site studies in the field of office automation

A group of users in Copenhagen were asked to evaluate how important a number of user interface characteristics were for them. The results show high importance of efficient daily use and of possibilities for exploratory learning while tutorial materials were of less importance. Users also were asked to evaluate four usability aspects of a number of popular programs. Results show that the quality pleasant to work with has the largest impact on evaluations of overall user‐friendliness while users seem able to view usability independently from the number of features in an application.     

基于NETCONF的SNMP MIB数据转换

针对SNMP网络管理技术难以满足网络配置管理需求的现状,利用XML在网络管理中的应用优势,提出一种SNMP管理信息库(MIB)到XML格式的数据转换模式。该模式对SNMP MIB数据进行合理的压缩和分类,分析MIB描述规范SMI和XML的语法特征并进行相应转换。该数据转换模式解决了NETCONF目前在数据建模方面的不足,使该协议实现具有更好的通用性和可扩展性。     

基于三层网络架构及DOM的XML系统模型

本文阐述如何在三层网络架构上运用XML以构造XML文档支持系统,提出了基于三层网络架构及DOM的XML系统的模型,该系统与传统的客户／服务器应用或是应用一般的数据传输方式如HTML等系统相比具有减少了网络流量、更有利于检索、可从多种不同的数据源集成数据、开放性、可扩充性、可重用性等一系列特点。     

Re-engineering the Engineering Change Management process for a drawing-less environment

Currently, 3D models and 2D drawings are the main basic elements that together form and carry the product definition throughout the product lifecycle. With the advent of the Digital Product Definition trend, industries have been interested in adopting a Model-based Definition (MBD) approach that enables the integration of drawing annotations directly onto a 3D model, thereby minimizing the need to generate engineering drawings. This drawing-less environment requires a way to adequately carry the product definition throughout a product's lifecycle while supporting all of the downstream users’ specific needs. The objective of this article is to present a solution to carry the Engineering Change Management (ECM) process in a drawing-less environment. Therefore, based on ECM process requirements from two Canadian aerospace companies, we propose an MBD dataset which consists of an MBD model and a distribution file. The proposed MBD dataset is evaluated and the MBD-driven ECM process is outlined.     

磁通压缩发电机的基本问题(I)

讨论了磁通压缩发电机(MFCG)的定义、工作原理、特征及其系统分类。虽然发电本身是通过外力做功获得电磁能的过程,但具体地,从空间电磁场角度,MFCG是通过压缩磁场所占空间以增大磁场密度的过程;按照电路模型,MFCG是通过减少电感以增大电流的过程。针对理想螺线管两种典型的工作模式,讨论了磁通守恒原理并论述了两种定义的一致性。总结了MFCG区别于普通发电机的根本特征,鉴于MFCG种类繁多,依据绕组结构和形状、电枢运动方式、适用的物理原理、应用领域等特性对19类MFCG进行了系统分类,并分别讨论了各类别的技术特征。这些基础性工作对MFCG概念研究和技术革新有重要参考意义。