带交易费的市场模型和未定权益套期保值

给出了有交易费的且多种股票参与交易的市场模型,并且讨论在此市场模型下的未定权益套期保值问题,在这一模型中,假定仅债券与股票之间有交易,而不同股票之间不直接进行交易以及交易费率是常数。     

液氧/煤油推进剂液体火箭发动机循环动力平衡分析

本文对以液氧/煤油为推进剂的发生器循环和分级燃烧循环方案进行了分析,求出了各种循环方案的最大室压,给出了室压、推力、燃烧室混合比和喷管出口直径对发动机比冲和系统平衡参数的影响,并探讨了平衡参数对效率、涡轮压比和发生器(或预燃室)混合比等设许参数变化的敏感性     

弹药可靠贮存寿命预计方法

本文针对现阶段弹药贮存可靠性数据不充分和研制阶段贮存可靠性评定比较困难的现状,提出了弹药可靠贮存寿命的4种预计方法,对每种方法的适用场合、实施步骤,特别是对相似产品法在弹药可靠贮存寿命中的应用做了较为详细的介绍。     

蠕变力学的今昔与展望

蠕变力学是一门悠久而又年轻的固体力学分支。为各种在高温、高压和其它严酷环境下工作的部件,如压力容器、管道、涡轮叶片等进行设计选定尺寸或估计有效服役寿命时,蠕变力学有重要的理论与实践意义,其任务是处理一些困难而严酷的工程问题。本文综述蠕变力学的主要进展,包括四个部分:1、蠕变研究的历史活动;2、蠕变研究的最新进展;3、常用的应力分析计算方法;4、蠕变破断与失稳。希望本文对于青年学者和工程师们有一定参考作用。     

由新比旧好元件组成的指数寿命系统的特性研究

文中研究了由独立的新比旧好元件组成的指数寿命系统,证明了:(i)对单调系统,它本质上是由指数寿命的元件串联而成;(ii)对系统的寿命是元件寿命的情形,除了一个元件是指数的外,其余元件的寿命分布均在零处退化。     

线膛火炮身管剩余寿命的神经网络模型研究

利用前馈式人工神经网络方法,根据试验数据,建立了某火炮身管剩余寿命(RL)模型;并用该模型研究了各特征截面内径改变量对弹丸初速改变量的影响,以及弹丸初速改变量与总内径改变量间的关系。     

不可逆闭式燃气轮机循环的最佳功率效率特性

本文研究恒温热源条件下不可逆闭式燃气轮机循环的有限时间热力学性能,导出其最佳功率输出与效率间的关系,它包含内可逆和理想换热条件下的最佳特性关系。     

三维半线性波动方程初值问题解的破裂

研究了半线性波动方程初值问题在三维空间中解的生命跨度的上界估计,关于此初值问题的爆破解将被建立。无论多么小的初值,该问题都没有整体解,在前人研究的基础上给出该初值问题解的生命跨度的上界估计。     

The US NATO and military burden sharing: post-Cold War accomplishments and future prospects

NATO burden sharing has become an especially timely issue in the past several years as a result of a number of factors, including Russian annexation of Crimea and destabilization of eastern Ukraine in 2014. This article argues that alliance unity among the great democracies of Europe and North America is indispensable to peace and stability on the Eurasian continent. A fractured NATO, and especially, a large divide in purposes or commitments as between the United States and its European security partners, invites aggression and the possibility of inadvertent escalation. Past successes and failures in US-involved multinational peace and stability operations, within and outside of Europe, show that mission accomplishment requires give and take, including the occasional acceptance of unequal costs and benefits among the members, in order to achieve peace and security objectives.     

Teaching Professional Ethos

This article investigates the communication of professional ethos, the ethical standards of a profession in training, from passing on ideas of patients’ welfare in medical schools to communicating values in military academies. The article examines this through a consideration of the consequences of Wittgenstein’s discussions on the nature of language: how words and sentences acquire meaning. Wittgenstein’s rule-following paradox, the paradox that any act can be brought into correspondence with a rule and thereby that any “meaning” might be applicable to what is being taught, must make us re-evaluate assumptions about a professional ethos as a guide for professionals in their future practice. If, as Wittgenstein asserts, the meaning of a word is its use, we must abandon ideas of an essence of professional ethos encapsulated in words. Ethical standards of the professions are not reducible to a set of rules. Instead teachers must seek to expand the learner’s repertoire of responses and invite different answers rather than a pre-established correct answer.