无线局域网802.11i安全加密技术探索

由于传输媒体的开放性,利用无线局域网进行通信要求其具有更高更完善的保密性能。通过分析无线局域网在网络安全方面的特性,提出无线局域网的安全框架和层次化的网络安全技术。并对IEEE802.11i协议的体系结构,数据加密技术IEEE802.11i进行剖析,探讨CCMP协议的工作安全性能。     

基于串空间理论的Kerberos协议安全性分析

在对串空间理论和Kerberos协议进行深入研究的基础上,采用串空间理论模型对Kerberos协议进行了安全性分析.分析的过程和结果证明,Kerberos协议满足串空间理论的认证性和服务器串随机数的秘密性,但不能保证发起者串随机数的秘密性,因此Kerberos协议能实现安全认证功能,但存在口令猜测攻击.针对此问题,对Kerberos协议进行改进,改进后的协议满足发起者串随机数秘密性,增强了抗口令猜测攻击的能力.     

WEP协议的安全性及在局域网中的应用

基于无线局域网IEEE820.11,对WEP协议的安全性机制进行分析,对其协议的解密、加密以及身份验证进行描述。在这一描述的基础上,又从IV的重复使用、IP重定向攻击等方面对WEP协议的漏洞进行分析,从而针对WPE协议的安全性,进行安全机制及局域网应用的分析。     

常用动态路由协议安全性分析及应用

随着动态路由协议的广泛应用,路由协议的安全性也越来越得到重视。然而,在路由协议的实际应用中,时常会发生路由协议的攻击事件。本文通过对3种较为常用的动态路由协议的应用研究,分析了RIPV2协议、OSPF协议、BGP协议这3种动态路由协议的安全性能,并进行总结。     

军队计算机网络的安全性分析

计算机网络在军队的安全建设中起着越来越重要的作用,营造一个健康安全的网络环境成为保障国防和军队安全建设的必要条件。本文分析了目前我国军队计算机网络所存在的安全隐患并提出了解决对策。     

分析建筑电气设计中的安全性和节能性

在经济迅速发展以及大众生活收入和水平不断提升的背景下,随着智能化以及自动化的深入,在建筑方面的电量消耗呈现出逐步增长的趋势,而且由于政府实施的城镇一体化计划,使我国的建筑用地面积也呈现出较高的年均增长率,与此同时,在能耗的方面,据相关部门调查统计得出,建筑能耗占据了国内全部方面总能耗的将近30%。综合以上各种因素,国家实施建筑方面的节能措施必须摆在显眼的位置。但是实施建筑节能,不仅要把实现节能作为主要的目标,还要考虑到人们的生活方面的一系列要求,即还要符合建筑功能的标准,给人们提供出一个安逸、便捷的生活区域,满足人们的愈来愈高的生活指标。围绕着存在于建筑电气设计中的节能和安全2个方面展开详细具体地阐述。     

纳米颗粒安全性分析及其研究现状

论述了纳米颗粒的特殊性质，通过信息传递模型分析了纳米颗粒作用于人体的过程，最后结合国内外纳米颗粒安全性研究现状给出了一些建议。     

飞机越界阻滞过程中乘客安全性分析

飞机越界工程材料阻滞系统是用来防止飞机冲出跑道的专用设备,该系统必须保证乘客在阻滞过程中的安全性。该文通过合理的简化建立了阻滞过程中乘客安全性分析的动力学模型,将问题归结为一组非线性动力学方程。然后,通过相空间变换将问题转化为一阶非线性微分方程组,采用Runge-Kutta方法对方程组进行数值求解,且开发了相应的仿真程序。仿真算例表明：该文建立的动力学模型和计算结果是合理可信的,利用该文方法可以进行阻滞过程中乘客安全性的评价。     

可拓学与创新方法国际研讨会征文启事

人类社会是在解决各种各样的矛盾问题和不断开拓创新中前进的。利用计算机和网络帮助人们处理矛盾问题和进行创新活动是人类的理想。可拓学作为研究实现这一理想的基本理论、方法和工具,用形式化模型探讨事物拓展与变换的可能性以及开拓创新的规律与方法,并用于解决矛盾问题的新学科。可拓学创立于1983年。近30年来,可拓学研究者们建立了较完善的理论体系———可拓论,研究了应用于各领域的可拓创新方法,开展了在信息、设计、自动化和管理等领域的应用———可拓工程。可拓论、可拓创新方法和可拓工程构成了新学科可拓     

一种具有用户匿名性和前向安全性的WTLS握手协议的安全性分析及其改进

对为实现用户匿名性和前向安全性的安全目标而提出的两种改进的WTLS握手协议——基于EC_DH密钥交换的握手协议和基于RSA密钥交换的握手协议进行了分析和研究,研究结果表明,基于RSA密钥交换的WTLS握手协议不能提供所预期的前向安全性。本文对该协议进行了改进,改进后的握手协议可以提供前向安全性。最后,对改进后的握手协议进行了简要的安全性与性能分析。     

A formal approach to the integrated analysis of security and QoS

Concurrent and distributed systems are subject to several requirements of different nature. Among them security and quality of service (QoS) are two fundamental aspects, which can have a profound impact on the system performability. Unfortunately, the study of the tradeoff between security guarantees and performance needs is hard to accomplish, because the related analysis activities are usually carried out separately. In this paper, we present an integrated and tool-supported methodology encompassing both activities, which can provide insights about how to trade the QoS delivered by a system with its security guarantees. The methodology is illustrated by assessing the effectiveness and the efficiency of the securing strategy implemented in the NRL Pump, a trusted device proposed to secure the replication of information from a low-security level enclave to a high-security level enclave.     

论信息防伪在卷烟防伪中的“立体化”应用

目的：——对于烟草行业，防伪的意义不仅在于减少公司经济利益的损失，还在于烟草品牌的保护。方法——利用高科技的信息防伪技术，打击质量或包装十分低劣的假冒卷烟的销售，会使消费者远离这些品牌。在全球范围内，打击假冒和走私卷烟是世界烟草行业共同面临的一个十分重大的问题。对于假冒和走私卷烟的数量，谁也无法给出一个确切的统计数字。据有关专家介绍，早在2000年，仅在中国境内就有1000亿支以上的假冒走私卷烟流入市场，这个数字相当于西班牙等中等产烟国一年合法的卷烟生产量。当年我国共收缴假冒卷烟57万件（合285亿支）。结果--假冒走私卷烟的质量和其假冒的品牌卷烟的包装的质量是无法相比的，但是，随着经济的繁荣，市场的诱惑，假冒走私卷烟也在花价钱追踪正宗厂家包装防伪技术。结论--毫不夸张地说，烟草的品牌保护是烟草公司的生命线。     

分布式任务关键系统生存性自动分析与验证

提出了一种应用概率模型检测技术进行分布式任务关键系统生存性的量化分析研究方法.该方法对攻击者和系统的交互行为进行精简抽象,在此基础上使用PRISM高级语言构造连续时间马尔可夫链系统概率模型.针对不同程度的攻击故障及系统服务水平,以连续随机逻辑建立系统生存性的形式化规约.借助概率模型检测工具PRISM对模型进行统计和验证,并图形化地表示出系统生存性的自动分析结果.理论分析和实验结果验证了上述方法的合理性和有效性,这些结果可在理论上指导可生存系统的设计和实现.     

Digitalization for supply chain resilience and robustness: The roles of collaboration and formal contracts

Black swan events such as the coronavirus (COVID-19) outbreak cause substantial supply chain disruption risks to modern companies. In today’s turbulent and complex business environment, supply chain resilience and robustness as two critical capabilities for firms to cope with disruptions have won substantial attention from both the academia and industry. Accordingly, this study intends to explore how digitalization helps build supply chain resilience and robustness. Adopting organizational information processing theory, it proposes the mediating effect of supply chain collaboration and the moderating effect of formal contracts. Using survey data of Chinese manufacturing firms, the study applied structural equation modelling to test the research model. Results show that digitalization has a direct effect on supply chain resilience, and supply chain collaboration can directly facilitate both resilience and robustness. Our study also indicates a complementary mediating effect of supply chain collaboration on the relationship between digitalization and supply chain resilience and an indirect-only mediation effect on the relationship between digitalization and supply chain robustness. Findings reveal the differential roles of digitalization as a technical factor and supply chain collaboration as an organizational factor in managing supply chain disruptions. Paradoxically, formal contracts enhance the relationship between digitalization and supply chain resilience but weaken the relationship between supply chain collaboration and supply chain resilience. The validation of moderating effects determines the boundary conditions of digitalization and supply chain collaboration and provides insights into governing supply chain partners’ behavior. Overall, this study enhances the understanding on how to build a resilient and robust supply chain.     

The application of the Six Sigma concept to port security process quality control

Greater heed has been paid to the matter of maritime security since the tragedy in the U.S.A. on 11 September 2001. A number of measures have been put into practice by ports to enhance security. More regulations and measures sometimes imply an increased probability of influencing port operations. Thus, the quality of the port security process regulated by measures is becoming essential. In this paper, the quality control in the port security process is demonstrated using the Six Sigma concept. It is concluded that it is crucial to distinguish each step of a security process clearly from the outset, furthermore, gathering quantitative data at each stage is the first priority. Copyright © 2007 John Wiley & Sons, Ltd.     

The impacts of biofuels on food security and supply in China

Biofuels are the current promising alternative to fossil fuels. However, the fluctuating food prices caused by oil price led to critics to biofuels. The paper surveyed biofuels production and grain production and consumption demand, and come to the concolusion that there was a little impact of corn ethanol on international food price, and there was no impact on China’s food prices. China has launched non-food biofuels development strategy to use marginal lands for growing hard crops, such as sweet sorghum, tuber crops, and switchgrass etc to produce biofuels without any impact on food security in the future.     

The impact of aviation checkpoint queues on optimizing security screening effectiveness

Passenger screening at aviation security checkpoints is a critical component in protecting airports and aircraft from terrorist threats. Recent developments in screening device technology have increased the ability to detect these threats; however, the average amount of time it takes to screen a passenger still remains a concern. This paper models the queueing process for a multi-level airport checkpoint security system, where multiple security classes are formed through subsets of specialized screening devices. An optimal static assignment policy is obtained which minimizes the steady-state expected amount of time a passenger spends in the security system. Then, an optimal dynamic assignment policy is obtained through a transient analysis that balances the expected number of true alarms with the expected amount of time a passenger spends in the security system. Performance of a two-class system is compared to that of a selective security system containing primary and secondary levels of screening. The key contribution is that the resulting optimal assignment policies increase security and passenger throughput by efficiently and effectively utilizing available screening resources.     

Design and analysis of DNA strand displacement devices using probabilistic model checking

Designing correct, robust DNA devices is difficult because of the many possibilities for unwanted interference between molecules in the system. DNA strand displacement has been proposed as a design paradigm for DNA devices, and the DNA strand displacement (DSD) programming language has been developed as a means of formally programming and analysing these devices to check for unwanted interference. We demonstrate, for the first time, the use of probabilistic verification techniques to analyse the correctness, reliability and performance of DNA devices during the design phase. We use the probabilistic model checker prism, in combination with the DSD language, to design and debug DNA strand displacement components and to investigate their kinetics. We show how our techniques can be used to identify design flaws and to evaluate the merits of contrasting design decisions, even on devices comprising relatively few inputs. We then demonstrate the use of these components to construct a DNA strand displacement device for approximate majority voting. Finally, we discuss some of the challenges and possible directions for applying these methods to more complex designs.     

Internet use and farm households food and nutrition security nexus: The case of rural Ghana

The impact of internet use on food and nutrition security of rural households in Ghana is investigated in this study. To offset the potential challenge of selection bias, an endogenous treatment regression (ETR) technique is utilized for the analysis.. The results reveal that Internet use can improve smallholder farmers’ food and nutrition security. Internet usage has a profound positive effect on the food security of households with off-farm work and larger size of landholding. Our results suggest the intensification of efforts to enhance Internet connectivity across the nation by the government and policymakers is essential since it can go a long way to affect household welfare. The findings also highlight the importance of information and communication technologies (ICTs), the Internet, patronization to improve rural household welfare.