宽带卫星通信和星际链路间激光通信的应用前景

提出了由于信息化社会、Ｉｎｔｅｒｎｅｔ、Ｉｎｔｒａｎｅｔ和多媒体技术的出现,从而要求卫星通信向多体制、多功能发展。文中着重分析了具有独特优点的激光通信在宽带卫星通信和星际链路中的现实商用前景。     

半导体激光器的光学准直

对半导体激光器进行光学准直是空间光通信系统必须进行的重要工作。文中简述了准直通常使用的方法,测试了使用单透镜对一种３５ｍＷ半导体激光器的准直结果,准直效率约为６０％,准直后的发射角为０４～０７５ｍｒａｄ。     

中国西部开发与美国西部开发的对比研究

通过对美国西部开发和中国西部开发的对比及借鉴美国西部的经济开发策略,对中国西部的经济发展提出了采取“梯度转移”与有条件的“增长极核发展”相结合的经济发展战略模式的建议。     

Optimization Model and Algorithm for Crew Management During Airline Irregular Operations

Airline irregular operations have long been a realm where human experience and judgement are the most important tools to utilize. Crew management during irregular operations is usually the bottleneck of the whole system-recovering process due to complicated crew schedules and restrictive crew legalities as well as the size and scope of the hub-and-spoke networks adopted by major carriers. A system-wide multi-commodity integer network flow model and a heuristic search algorithm for the above purpose are presented and discussed in this paper. The computational experiences show that the algorithm is efficient enough to solve problems of realistic size and also has the flexibility to accommodate practical business requirements.     

Compliance Versus Risk in Assessing Occupational Exposures

Assessments of occupational exposures to chemicals are generally based upon the practice of compliance testing in which the probability of compliance is related to the exceedance [γ, the likelihood that any measurement would exceed an occupational exposure limit (OEL)] and the number of measurements obtained. On the other hand, workers’ chronic health risks generally depend upon cumulative lifetime exposures which are not directly related to the probability of compliance. In this paper we define the probability of “overexposure” (θ) as the likelihood that individual risk (a function of cumulative exposure) exceeds the risk inherent in the OEL (a function of the OEL and duration of exposure). We regard θ as a relevant measure of individual risk for chemicals, such as carcinogens, which produce chronic effects after long-term exposures but not necessarily for acutely-toxic substances which can produce effects relatively quickly. We apply a random-effects model to data from 179 groups of workers, exposed to a variety of chemical agents, and obtain parameter estimates for the group mean exposure and the within- and between-worker components of variance. These estimates are then combined with OELs to generate estimates of γ and θ. We show that compliance testing can significantly underestimate the health risk when sample sizes are small. That is, there can be large probabilities of compliance with typical sample sizes, despite the fact that large proportions of the working population have individual risks greater than the risk inherent in the OEL. We demonstrate further that, because the relationship between θ and γ depends upon the within- and between-worker components of variance, it cannot be assumed a priori that exceedance is a conservative surrogate for overexposure. Thus, we conclude that assessment practices which focus upon either compliance or exceedance are problematic and recommend that employers evaluate exposures relative to the probabilities of overexposure.     

澳门社区治理模式的特征及启示

本文从治理主体和治理路径入手分析澳门治理模式的突出特征,研究发现澳门政府、社区组织和居民组成的治理主体权责分明、各尽其事,运用社会工作、公民教育和咨询协商等治理路径为澳门社区居民构建美好家园、和谐社区,这些突出特征为反思中国大陆社区治理主体多元化和治理路径有效性提供重要参考.     

三社联动:城市社区治理中的策略变革 ——来自昆明市L社区的治理经验

在全面深化改革与国家治理现代化的大背景下,发挥多方力量参与城市社区建设和自我管理,开展居民互助服务,在建设和谐城市社区中具有重要作用.个案甄选与梳理昆明市L社区治理,能够准确瞄准当下社区治理的突破口和把握城市社区多元力量参与社区发展的契合规律.同时,多角度、全方位分析城市社区建设推进中遇到的现实隔阻,能够明确城市社区治理中多元力量利用不尽充分.基于此,从社区主导、实践推动、嵌入发展、机制构建等四个方面深入论证其治理成效,以揭示如何实现城市社区治理中的策略变革.     

为了真实和正义的历史重述——论何顿的《黄埔四期》

《黄埔四期》重述了自北伐至“文革”后这半个多世纪以来的中国历史,力图以文学的方式祛除政治对历史的遮蔽,挖掘那些被隐没的史实;用传奇的笔法展示那些被历史埋没的英雄,再现中华民族伟大的抗战史, 还民族英雄以应有的尊重。     

习近平建设海洋强国重要论述研究

习近平建设海洋强国重要论述经历了率先发出“向海进军”号召、明确提出海洋经济强省建设、庄严宣告海洋强国建设三个阶段。习近平建设海洋强国重要论述主要包括发展海洋经济、保护海洋环境、创新海洋科技、维护海洋权益等。习近平建设海洋强国重要论述具有三个鲜明的特点：在海洋强国建设“目的性”上做到了为国富强与为民谋利的统筹;在海洋强国建设“方法论”上做到了矛盾论和系统论等方法的统筹运用;在海洋强国建设“治理观”上实现了国际治理与国家治理的统筹。习近平建设海洋强国重要论述具有重要的区域意义——指导有关沿海省份创建海洋强省示范区、国家意义——强力推进海洋强国建设并取得了重大突破、世界意义——为全球海洋治理提供“中国方案”和“中国经验”。