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81.
邱向群 《计算机应用与软件》1994,11(3):61-64,F003
本文介绍了六种子目录加密法,这些方法在作者的工作中经过检验证明是行之有效和简单易行的。文中对这些加密法进行了比较并给出了一些实施细节。 相似文献
82.
83.
Chih-Hung Wang Author Vitae Chih-Heng Yin Author Vitae Author Vitae 《Computers & Electrical Engineering》2006,32(5):364-375
The most efficient approach to a fair exchange is to use an off-line trusted third party (TTP for short) who gets involved only when a dispute between two parties occurs. However, exchanged secrets that are not protected properly may be exposed to the TTP when one of these two parties asks the TTP to mediate the dispute. The first work to protect exchanged secrets from TTP’s misuse was proposed by Franklin and Reiter in 1997. They provided an on-line semi-trusted third party instead of an off-line third party for a fair exchange. Their schemes forced the TTP to take part in the protocol for all the cases, and thus, deemed to be impractical.The present paper, introduces several models, including single and multiple TTPs, to focus the attention not only on security properties, but also on reliability functions. In the single TTP mode, our new scheme can protect the exchanged data through an efficient exchange protocol, whereas in the multiple TTP mode, we proposed an approach to balance the security level with the reliability of the system. 相似文献
84.
《Information Systems Management》2007,24(4):305-310
Most organizations have measures to protect their network infrastructure from intruders. With the growth AND AVAILABILITY of wireless, some intruders now are aiming their attacks there. The potential for damage from these types of attacks is significant due to their nature. However, there is another type of wireless attack on organizational resources that also poses a significant vulnerability. That is electromagnetic radiation, also called radio frequency emissions (RFE), from unprotected systems and networks. 相似文献
85.
《Information Systems Management》2007,24(4):281-287
This study presents results of a survey of self-proclaimed computer hackers about their perceptions in regards to illegal hacking. Results show that hackers continue to engage in illegal hacking activities despite the perception of severe judicial punishment. A closer look shows that hackers perceive a high utility value from hacking, little informal sanctions, and a low likelihood of punishment. These perceptions coupled with a high level of moral disengagement partially explain the hacker's illegal behavior. 相似文献
86.
Christoph Minnameier 《Information Processing Letters》2007,103(3):105-111
Interaction systems are a formal model for component-based systems. Combining components via connectors to form more complex systems may give rise to deadlock situations. We present here a polynomial time reduction from 3-SAT to the question whether an interaction system contains deadlocks. 相似文献
87.
88.
Early warning systems (EWS) tend to focus on the identification of slow onset disasters such famine and epidemic disease. Since hazardous environmental conditions often precede disastrous outcomes by many months, effective monitoring via satellite and in situ observations can successfully guide mitigation activities. Accurate short term forecasts of NDVI could increase lead times, making early warning earlier. This paper presents a simple empirical model for making 1 to 4 month NDVI projections. These statistical projections are based on parameterized satellite rainfall estimates (RFE) and relative humidity demand (RHD). A quasi-global, 1 month ahead, 1° study demonstrates reasonable accuracies in many semi-arid regions. In Africa, a 0.1° cross-validated skill assessment quantifies the technique's applicability at 1 to 4 month forecast intervals. These results suggest that useful projections can be made over many semi-arid, food insecure regions of Africa, with plausible extensions to drought prone areas of Asia, Australia and South America. 相似文献
89.
XSLT is a very popular and flexible language for transforming XML documents which provides a powerful implementation of a tree‐oriented transformation language for transmuting instances of XML using a single vocabulary into a desired output. In this paper, we propose a processing model that enables the XSLT processor to encrypt and decrypt XML documents. The details of the implementation are presented. Our model supports a more general encryption scope than previous models. The implementation and experimental results demonstrate the practicality of the proposed model. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
90.
结合燕化公司网络病毒防治系统的实施,介绍了公司网络病毒防治系统的体系结构,并对公司网络病毒防治系统的运行管理提出了看法。 相似文献