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徐涤 《计算机光盘软件与应用》2012,(3):41-42
随着电子政务的发展,计算机信息系统的安全问题日益突出。如何构建一个安全、高效的涉密计算机信息系统应用环境,已经成为当前政府信息化中的关键问题。本文从一般信息系统发生安全事件对信息系统造成的后果出发,探究其发生原因,分析地方政府涉密信息系统可能面临的安全威胁,进而提出相应的保护防范对策建议。 相似文献
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The paper suggests a new methodology for secure cyber–physical systems design. The proposed methodology consists of two main cycles. The main goal of the first cycle is in design of the system model, while the second one is about development of the system prototype. The key idea of the methodology is in providing of the most rational solutions that are improving the security of cyber–physical systems. Such solutions are called alternatives and built according to functional requirements and non-functional limitations to the system. Each cycle of the methodology consists of the verification process and seven stages that are associated with the used cyber–physical system model. The objective of the verification process is in checking of constructed models and prototypes in terms of their correctness and compatibility. The model represents cyber–physical systems as sets of building blocks with network between them, takes elements internal structure into account and allows direct and reverse transformations. The novelty of the suggested methodology is in the combination of design, development and verification techniques within a single approach. To provide an example of the design methodology application, in this paper it is used to improve the semi-natural model of the railway infrastructure. 相似文献
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In this paper, we present a detailed and systematic overview of communication security aspects of Multi-Processor Systems-on-Chip (MPSoC) and the emerging potential threats on the novel Cloud-of-Chips (CoC) paradigm. The CoC concept refers to highly scalable and composable systems, assembled not only at system design-time using RTL, like traditional SoC, but also at integrated circuit (IC) packaging time thanks to 3D-IC integration technology. Practical implementation of CoC systems needs to solve the problem of scalable, configurable and secure communication not only between different functional blocks in a single ICs, but also between different ICs in a single package, and between different packages on the same or different PCBs and even between different systems. To boost such extremely flexible communication infrastructure CoC system relies on Software-Defined Network-on-Chip (SDNoC) paradigm that combines design-time configurability of on-chip systems (NoC) and highly configurable communication of macroscopic systems (SDN). This study first explores security threats and existing solutions for traditional MPSoC platforms. Afterwards, we propose SDNoC as an alternative to MPSoC communication security, and we further extend our discussion to CoC systems to identify additional security concerns. Moreover, we present a comparison of SDNoC based approach over existing approaches and discuss its potential advantages. 相似文献
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BackgroundFire protective ensembles (FPEs) are essential to safely perform firefighting job tasks; however, they are often burdensome to the workers. The aim of this study was to compare three internationally certified fire protective ensembles from the European Union (EU), South Korea (SK), and United States (US) on physiological responses, mobility, and comfort.MethodsTen male professional firefighters performed a battery of exercises in the laboratory following the ASTM F3031-17 standard to evaluate mobility, occupation-specific performance, and physiological responses (body weight, heart rate (HR), core temperature (Tc), breathing rate (BR), and rating of perceived exertion (RPE)) to 20 min of treadmill walking (3.2 mph, 5% incline). All participants carried out the evaluation wearing each FPE in a random order. Mixed effects models examined time (pre-vs. post-) by ensemble (EU, SK, US) interactions for all physiological variables and compared comfort, performance, and subjective variables across ensembles.ResultsNo interaction effects were observed for body weight, HR, Tc, BR, or RPE (p = 0.890, p = 0.994, p = 0.897, p = 0.435, and p = 0.221; respectively). SK had greater trunk flexion than EU (78.4° vs. 74.6°, p = 0.026) and US had lower standing reach than EU (105.5 cm vs. 115.4 cm, p = 0.004). Agility circuit time was lower in US (9.3 s) compared to EU (9.8 s) or SK (9.9 s) (p = 0.051 and p = 0.019, respectively).ConclusionsThe findings suggest that physiological burden remained largely unchanged across the international FPEs. However, mobility, performance, and comfort may be significantly influenced across types. International stakeholders and end users should consider design implications when choosing fire protective ensembles. 相似文献
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针对目前虚拟服务器的安全问题进行研究。设计了一种新的Web虚拟服务器应用安全的解决方案,在代码一级对其攻击进行检测和防护。即一方面,确定代码位置,利用特定的API调用在其前后对用户输入相关的参数进行判断是否含有可能的攻击存在并进行相应的处理;另一方面在应用源代码或中间代码文件中插入本方案的检测代码,以实现防护的功能。 相似文献
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作为新型的劫持系统内核技术,Windows Bootkit具有较强的隐蔽性和免杀能力,引发了严峻的计算机安全问题。通过分析研究Windows Bootkit的实现方式,并结合可信计算检测原理,设计了一种基于可信计算技术的Windows Bootkit检测系统,应用结果表明,该系统能检测出各种形式的Windows Bootkit,可有效增强Windows操作系统下计算机的安全性。 相似文献
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