一般阶段任务系统的任务可靠性分析

研究一般PMS的任务可靠性分析.首先给出一个五元组分析模型,该模型能够有效描述阶段持续时间是随机分布的、阶段内行为特性符合马尔可夫再生过程的一般PMS;为了降低计算复杂度,分析模型的求解过程由两个步骤组成,首先利用马尔可夫再生过程理论,给出一般PMS的阶段内随机过程分析公式和简化计算方法;然后给出一般PMS任务可靠性分析公式和简化计算方法.应用该分析模型和求解方法,可以有效地对一般PMS进行可靠性分析.     

使命必达：从新人到“达人”

金庸在《鸳鸯刀》中写道，称霸江湖的秘诀原来只是“仁者无敌”四个字。那么，顺风顺水行走职场“江湖”的秘诀又是什么呢？     

使命必达：从新人到“达人”

金庸在《鸳鸯刀》中写道,称霸江湖的秘诀原来只是"仁者无敌"四个字。那么,顺风顺水行走职场"江湖"的秘诀又是什么呢?     

使命必达:从新人到"达人"

"天下风云出我辈,一入江湖岁月催.皇图霸业谈笑中,不胜人生一场醉.提剑跨骑挥鬼雨,白骨如山鸟惊飞.尘事如湖人如水,只笑江湖几人回."这首诗,似曾相识吧?森森然的杀气,跃然纸上;凛凛然的豪气,破墙而出.在《东方不败》的电影版故事里,岳灵姗在掩埋完被分尸的骏马后吟颂出这首浸满江湖风雨的诗句.……     

Mission Security

James Bit — der Name ist Programm. Im Auftrag von T-Systems sorgt der virtuelle Mitarbeiter für Informationssicherheit.     

Revising Our Mission

This issue's column presents highlights from our 2006 editorial board meeting to help you better understand where we see the magazine going.     

信息安全与网络安全关系辨析

随着科学技术和网络信息技术的飞速发展,越来越多的网络信息安全问题逐渐出现.本文主要研究了网络信息安全和网络安全之间的关系,并且对如何创造安全的网络环境提出了几点建议.     

Managing network security: Time-based security

Over the last few years, computing has changed to an almost purely networked environment, but the technical aspects of information protection have not kept up. As a result, the success of information security programmes has increasingly become a function of our ability to make prudent management decisions about organizational activities. This series of articles takes a management view of protection and seeks to reconcile the need for security with the limitations of technology.     

Managing network security: Simulating network security

Computing operates in an almost universally networked environment, but the technical aspects of information protection have not kept up. As a result, the success of information security programmes has increasingly become a function of our ability to make prudent management decisions about organizational activities. Managing Network Security takes a management view of protection and seeks to reconcile the need for security with the limitations of technology.     

The Entrapment/Escorting Mission

The problem of escorting a moving target with a team of mobile robots was solved in this article by resorting to a formation control algorithm that can be cast in the framework of the NSB control approach. The overall mission, therefore, is decomposed into properly defined elementary tasks that are hierarchically arranged, so that the higher-priority tasks are not influenced by the lower-priority ones. The validity of the proposed approach has been proved by both simulation case studies and experimental results with a team of six Khepera II mobile robots. Stability analysis concerning effective conditions needed to verify that the behaviors of specific missions are properly defined and merged is under investigation. Future improvements might regard decentralization of the algorithm, consideration of the vehicles' nonholonomicity in the definition of the task functions, and the introduction of a piecewise-constant constraint for the linear velocity to allow application of the method to teams of cruise vehicles (e.g., a fleet of vessels or a flight of planes).     

机动防空任务聚合级装备作战单元维修性仿真

装备作战单元在执行任务过程中常处于聚合状态,影响其作战效能的重要因素之一就是任务维修性。任务维修性的度量参数有多种,文中采用恢复功能的任务时间（MTTRF）,在分析聚合级装备作战单元层次和特性的基础上,剖析了聚合级装备作战单元MTTRF的具体含义;给出了在机动防空任务下聚合级装备作战单元MTTRF的仿真方法和流程,应用Petri网技术在ExSpect仿真环境下建立了聚合级装备作战单元机动防空任务下维修性的仿真模型,实现了对聚合级装备作战单元各层MTTRF的仿真。最后,通过一个实例对模型进行验证。     

主流操作系统安全性分析及安全策略

随着全球信息化时代的来临,使用互联网办公和娱乐的人越来越多,但人们对网络操作系统的安全意识却相对薄弱。操作系统是计算机系统运行的基础,也是构筑网络信息系统的基础。该文对主流操作系统进行了对比分析,并提供了几种操作系统安全策略。     

A security evaluation framework for cloud security auditing

Cloud computing is clearly one of today’s most enticing technologies due to its scalable, flexible, and cost-efficient access to infrastructure and application services. Despite these benefits, cloud service users (CSUs) have serious concerns about the data security and privacy. Currently, there are several cloud service providers (CSPs) offering a wide range of services to their customers with varying levels of security strengths. Due to the vast diversity in the available cloud services, from the customer’s perspective, it has become difficult to decide which CSP they should use and what should be the selection criteria. Presently, there is no framework that can allow CSUs to evaluate CSPs based on their ability to meet the customer’s security requirements. We propose a framework and a mechanism that evaluate the security strength of CSPs based on the customer’s security preferences. We have shown the applicability of our security evaluation framework using a case study.     

Personal security

I am sitting on a plane, listening to two executives outline their strategy for a major buyout of a bridge/router vendor. Since I am a geek and understand what they are talking about, it's an interesting set of tactics that they are considering to get the price of the company down to something they want. What's even more interesting is how open they are with what they are talking about and, even more, I know the president of the company which they are planning to acquire. It would be very easy for me to make a phone call when we land and completely trash all their plans.     

RFID security

Radio Frequency Identification (RFID) systems have become popular for automated identification and supply chain applications. This article describes the technical fundamentals of RFID systems and the associated standards. Specifically, we address the security and privacy aspects of this relatively new and heterogeneous radio technology. We discuss the related security requirements, the threats and the implemented mechanisms. Then the current security and privacy proposals and their enhancements are presented. Finally we discuss the role of this technology in Ubiquitous Computing.     

Computer security

Computer security has hit the mainstream. This paper is a high-level treatment of computer security, its concepts and terminology, and some pointers about where to go for more information.