安全联盟与经济合作研究——基于四种联盟类型的分析

联盟建立的初衷是为了满足国家在安全上的需要。但在无政府状态的国际社会中,经济交往产生的安全外部性促进了结盟国家间贸易往来的增加,确保了联盟国家间经济交往的发展;在联盟建立和发展过程中,联盟框架内存在的议题联系机制为联盟国家之间进行安全合作的同时实现经济合作提供了相应的交往渠道和方式。同时,一国通过经济上的补偿性支付的方式向其盟国提供经济补偿,使其从经济上获益,从而确保了安全联盟的稳定。根据联盟成员间的相互依存度和利益相容性程度,联盟会表现为实力增强型联盟、协调型联盟、霸权型联盟和飘忽不定型联盟等四种类型,联盟经济在各种类型的联盟中都会发挥作用;但在不同类型的联盟中,由于上述两个变量的不同,经济合作与安全利益的关联程度会有不同的表现,补偿性支付也会发挥不同的作用。     

逆合成孔径雷达图象的旁瓣清除技术

<正> 随着改革开放的扩大和深入,我国以吸收利用外资为重点的三资企业发展迅速。到1992年一季度,共批准外商投资企业32000多家,吸收外资230亿美元,年递增率达30％以上。1992年,全国合资企业出口创汇可望达到100亿美元。三资企业不仅发展速度比较快,而且走势也在发生新的变化。总结分析外商投资走势,引导三资企业向高新层次递进,对于加大我国开放力度,促进外向型经济的良性发展,是十分必要的。     

美国是东亚区域合作的推动者还是阻碍者?

冷战结束至今,东亚区域合作得到了很大发展。地区多边组织、论坛、会议、自由贸易区等区域合作形式在本地区的政治、安全和经济等诸多领域中扮演着日益重要的角色,包括中国在内的东亚国家都已经在不同程度上介入区域多边合作进程之中。东亚区域合作的进程可能对未来美国与东亚的关系产生意义深远的影响。美国主要根据其自身利益的判断来应对东亚区域合作,对于把美国排除在外的区域合作形式可能采取不欢迎的态度,对于把美国包括在内的区域合作形式则可能采取积极推动的立场。     

以非线性理论阐述反馈振荡器的频率与幅度的稳定性

本文首先对线性的频率稳定理论用于近似正弦反馈振荡器的线性频率稳定理论,进行了评论性的回顾。在这方面,解释所谓的线性振荡器是清楚的。其后,是应用描述函数法和判决方程法所得到新的表达式,去阐述反馈振荡器考虑成一个非线性网络时的振荡频率和振荡幅度的稳定性。     

Real Exchange Rate Dynamics in the Asian Economies: Can Regime Shifts Explain Purchasing Power Parity Puzzles?

Abstract

We show that the strong version of the purchasing power parity (PPP) hypothesis holds in most of the US dollar real exchange rates using cointegration method that accounts for breaks in the models. The break dates in seven of the Asian currencies coincide with the two rounds of currency depreciation recorded during the 1997–1998 financial crises. We obtain a mean half-life estimate of about 10 months for PPP to converge to its long-run equilibrium level. Our confidence intervals based on persistence profile approach for the half-lives is much narrower than previous evidence might indicate. Taken together, these results show that mean reversion is stronger than commonly thought.     

Program Evaluation and Review Technique (PERT) in Construction Schedule Risk Assessment

Construction project scheduling is one of the most critical factors for project success measurement.Not only for the project planning but for construction process management,the scheduling is the basic tool for communication between the owner and the project manager.By developing the schedule before the project starts,the owner knows in advance that the expected timeline of the project.By preparing construction process scheduling,the owner and general contractor can better manage the subcontractors,sub-trades progress,materials storage and deliveries,labors schedule and equipment set up which will eventually save time,money and hassle.Basically,Critical Path Method(CPM) is commonly used in the construction industry.CPM is a deterministic method that assumes that through the network,there is at least one path that determines the project duration and that the path is the critical path.CPM does not consider the uncertainty in the activities;rather it assumes that each activity can be finished in the given situation.Program Evaluation and Review Technique(PERT) is a stochastic technique which is based on the assumption that the duration of a single activity can be described by a probability density function.PERT takes into account the uncertainty during the construction process and has been created out of the need to plan,schedule and control complex projects with many uncertainties.The PERT approach is stated in some books and papers,but there is no deep investigation on the application in the schedule risk assessment.This paper investigates the PERT work process and takes a valuable try on the construction schedule risk assessment by using case studies.The utilization in the estimate the construction liquidated damage with the uncertainties is performed,which also can be used in the insurance company to calculate the insurance premium.     

微波反馈放大器匹配及增益带宽的研究

本文介绍的是小信号微波反馈放大器的分析与综合。放大器是采用通常的增益级的框图,并取并联反馈。文中提供全部网络元件值的估算和预测闭环宽频带增益、带宽和双端口的匹配值。简述匹配值与增益用图解法的权衡。最后描述了综合方法并举例说明设计实例。