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61.
入侵检测系统分类法技术研究   总被引:2,自引:0,他引:2  
首先阐述了IDS的发展历史,接着从IDS分类法的发展对现有的IDS分类法进行了介绍,回顾常见的IDS分类,并对IBM提出的IDS分类法进行了介绍和简要分析。最后通过分析现状对IDS的发展趋势进行了探讨。  相似文献   
62.
基于GSM GPS短消息的车载移动终端的设计与实现   总被引:3,自引:0,他引:3  
为了解决对城市车辆进行实时监督和统一管理的问题,基于GPS全球定位系统和GSM数字蜂窝网,以性价比较高的AVR微控制器开发设计了GPS车载移动终端设备.终端通过GPS获取当前位置和时间信息,并以短消息的形式通过GSM网络发往监控中心,在中心的电子地图上实时地显示出来.同时监控中心的控制指令,如跟踪监听,遥控设置等,通过GSM网络发往车辆上的终端设备,从而实现了系统的交互运作.终端功耗低,体积小,操作简单,便于在系统升级和维护.  相似文献   
63.
A manufactured home is a factory-built house constructed in a controlled factory environment according to federal standards known as the Department of Housing and Urban Development (HUD) code. The manufactured home shares approximately 20% of the total housing units in the United States and plays an important role in providing affordable housing. However, in terms of material engineering, advanced techniques are scarcely used in the manufactured housing (MH) industry. The current material flow and control systems are characterized as independent demand systems that are based on the personal experience of the material managers. Although independent inventory control systems are widely used in many manufacturing industries, these systems lead to a large amount of inventory and have many drawbacks for the MH industry. On the other hand, dependent inventory systems can reduce unfavorable inventory levels using new techniques and present substantial benefits for the MH industry. This paper applies lean inventory control systems and supply chain management techniques to the current systems of the MH industry and proposes a new framework of material control systems as one of the system management tools.  相似文献   
64.
Flexible manufacturing systems (FMS) are very complex systems with large part, tool, and information flows. The aim of this work is to develop a knowledge-based decision support system (KBDSS) for short-term scheduling in FMS strongly influenced by the tool management concept to provide a significant operational control tool for a wide range of machining cells, where a high level of flexibility is demanded, with benefits of more efficient cell utilization, greater tool flow control, and a dependable way of rapidly adjusting short-term production requirements. Development of a knowledge-based system to support the decision making process is justified by the inability of decision makers to diagnose efficiently many of the malfunctions that arise at machine, cell, and entire system levels during manufacturing. In this context, this paper proposes three knowledge-based models to ease the decision making process: an expert production scheduling system, a knowledge-based tool management decision support systems, and a tool management fault diagnosis system. The entire system has been created in a hierarchical manner and comprises more than 400 rules. The expert system (ES) was implemented in a commercial expert system shell, Knowledge Engineering System (KES) Production System (PS).  相似文献   
65.
以国家档案局科技攻关项目为背景,讨论了系统工程理论与方法在系统分析阶段的应用,从技术分析角度对集成化网络环境下电子归档的需求和流程进行分析和探讨,并对模块化的开发方法进行了一些研究讨论。  相似文献   
66.
Summary. We set out a modal logic for reasoning about multilevel security of probabilistic systems. This logic contains expressions for time, probability, and knowledge. Making use of the Halpern-Tuttle framework for reasoning about knowledge and probability, we give a semantics for our logic and prove it is sound. We give two syntactic definitions of perfect multilevel security and show that their semantic interpretations are equivalent to earlier, independently motivated characterizations. We also discuss the relation between these characterizations of security and between their usefulness in security analysis.  相似文献   
67.
基于框架与规则相结合的棉纺工艺专家系统知识库的设计   总被引:3,自引:0,他引:3  
本文讨论了棉纺工艺专家系统及其知识表示方法。在介绍棉纺工艺专家系统体系结构的基础之上,重点探讨了利用框架表示棉纺工艺的领域知识的具体方法、框架结构以及用框架一规则形式来表示推理规则及原理。并简要介绍了本系统基于事例的推理过程。  相似文献   
68.
It is argued that classical measures of computer system performance, for example mean response time, are inadequate in the context of fault-tolerant system design. Alternative, perception-based measures are proposed and theorems established describing their properties. Focus is directed upon the homogeneous M/M/m system in which total processor power is constrained by budget and processors are subject to failure and repair. A numerical technique for extracting both classical and perception-based measures from the associated two-dimensional Markov process is offered, along with bounds on time and space required for its execution. It is seen that the perception-based approach to system design can call for twice as many processors as the classical approach.  相似文献   
69.
The purpose of this paper is to show that a first-order adaptive regulator globally stabilizes a class of infinite-dimensional systems having no right half plane zeros. Knowledge of the spectrum of the model's high-frequency gain is not required.  相似文献   
70.
Decision support systems depend on a variety of knowledge management techniques. These range from data base management, programming, and spreadsheet analysis to rule set management and automated inference. One valuable knowledge management technique that has yet to find its way into the repertoire of decision support system developers is general-purpose demon management. This article identifies and explores the major issues pertaining to the integration of demon representation and processing into a knowledge management environment. These serve as a basis for design and implementation of more flexible and powerful environments for decision support.  相似文献   
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