提高铁路货物及时送达可靠性的途径

对货物及时送达可靠性的内涵进行界定,认为及时运输是货物运输的共同要求.从更新硬件设施、实行差别化策略、推进运输代理制度、健全运输法规、建立考核制度、推进信息化建设和整合货运系统等方面提出提高货物及时送达可靠性的途径.     

降价浪潮下的购车新视角 关注汽车保值率

“房价上涨，汽车降价”是近两年来最热门的话题．不少人刚买了主就开始过上了提心吊胆的日子，生怕一觉醒来自己的资产又“蒸发”了几万，在这种状况下．买辆保值车就显得尤为有意义。在国内汽车保值率仍是一个比较新鲜的概念．但在汽车消费十分成熟的国家，车型保值率早已被视为选购汽车的指标之一，消费者在购买时往往更愿意考虑保值率高的车型。     

高速柴油机正时传动部分的优化研究

本文通过对某柴油机失效分析，设计了正时传动部分的优化方案，提高柴油机的可靠性，并通过了试验验证。     

I—5—4产品工艺设计中可靠性分析的运用

在I—5—4产品的原材料到镦饼工序，采用FMEA进行过程的可靠性分析，改进工艺设计，降低裂纹的发生频度，从而降低裂纹的产生风险，达到提高过程可靠性的目的。因此进行过程FMEA分析可以提高工艺设计水平，提高产品质量。     

DESIGN OF A DIGITAL SIGNATURE SCHEME BASED ON FACTORING AND DISCRETE LOGARITHMS

Objective Focusing on the security problem of authentication and confidentiality in the context of computer networks, a digital signature scheme was proposed based on the public key cryptosystem. Methods Firstly,the course of digital signature based on the public key cryptosystem was given. Then, RSA and ELGamal schemes were described respectively. They were the basis of the proposed scheme. Generalized ELGamal type signature schemes were listed. After comparing with each other, one scheme, whose Signature equation was (m r)x=j s modФ(p) , was adopted in the designing. Results Based on two well-known cryptographic assumptions, the factorization and the discrete logarithms, a digital signature scheme was presented. It must be required that s“ was not equal to p‘q“ in the signing procedure, because attackers could forge the signatures with high probabilities if the discrete logarithms modulo a large prime were solvable. The variable public key “e“ is used instead of the invariable parameter “3“ in Ham‘s signature scheme to enhance the security. One generalized ELGamal type scheme made the proposed scheme escape one multiplicative inverse operation in the signing procedure and one modular exponentiation in the verification procedure.Conclusion The presented scheme obtains the security that Harn‘s scheme was originally claimed. It is secure if the factorization and the discrete logarithms are simultaneously unsolvable.     

车流疏理中关于各项指标计算方法的设计与实现

为满足重新制定全路车流径路的需求,需要疏理现有全路重车车流.它为制定新的车流径路提供调整的数据基础,并为编组计划开行直达列车提供车流数据.车流疏理就是抽取全路实际重车流数据,疏理重车车流表.在车流疏理中,各项指标的变化是车流疏理人员重点关注的部分.设计了能够快速、正确的完成车流疏理时各项指标的运算方法.     

铁路电力配电所跨所供电设计面面观

对铁路电力配电所跨所供电条件进行设计探讨。通过对有关铁路设计规范与铁路运行规程的比较,指出存在的问题。从设计与运行的角度,对配电所跨所供电进行技术、经济、可靠性、节能方面的分析,客观指出配电所跨所供电的利弊,以及设计中应该注意的事项,并对配电所跨所供电提出建议。