童亭矿锚杆支护安全可靠性控制

简要介绍了煤巷锚杆支护技术在童亭煤矿的应用推广情况 ,重点介绍了童亭煤矿在安全可靠性控制方面强化管理、优化设计、提高工艺水平和质量保证体系建设的一些经验和做法 ,并对今后发展煤巷锚杆支护技术提出了看法。     

新形势下的研究生思想政治工作探索

在新的历史时期 ,研究生思想状况受市场经济的影响呈现出业务学习积极、开放竞争意识强化 ,价值取向多元化、道德观念复杂化 ,集体主义淡化、个人意识加强等多样化特征 ,使研究生思想政治工作更为复杂、更为艰巨。针对这种形势 ,本文提出研究生思想政治工作必须立足于研究生思想状况多样化的现实 ,采取多种措施才能做好研究生思想政治工作 ,并进一步提出了新的历史时期开创研究生思想政治工作新局面应采取的对策措施     

六种子目录加密法

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。     

网络安全技术研究

网络安全问题已经成为网络发展中急需解决的问题。已经引起人们的重视。给出了网络安全的概念，网络所面临的威胁，提出了解决网络安全的相关技术。     

How to protect exchanged secrets in the fair exchange protocol with off-line TTP

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.     

Electronic Emissions Security: Danger in the Air

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.     

Hacking into the Minds of Hackers

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.     

Local and global deadlock-detection in component-based systems are NP-hard

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.     

Intra-seasonal NDVI change projections in semi-arid Africa

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.