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781.
对几种超高层建筑内部的分区供水方式原理及其优缺点进行了分析,以某超高层建筑为例,分析了消防给水系统的供水方式,以及此供水方式下系统的压力流量和组件的设置,并与《高层民用建筑设计防火规范》中的相关要求进行比较,分析在超高层建筑特有的供水方式下固定灭火设施的各项参数是否符合规范要求,为超高层建筑的消防给水设计提供了一定的借鉴和参考.  相似文献   
782.
描述了在VC++环境中开发的基于VISA接口标准的射频半实物仿真系统校准自动测试程序.利用VISA函数与接口无关、与操作系统无关、与编程环境无关的特点,通过GPIB总线和SCPI标准命令对矢量网络分析仪进行程序控制,达到空间辐射信号精确测量的目的,实现了目标阵列的宽带特性校准.  相似文献   
783.
Australia is a geographically large country, with the world's longest national coastline to defend, but a relatively small economy of some 17.5 million people. Since World War II, Australia has faced the dilemma of how to structure defence policy in the absence of an identifiable threat. Its policy of self‐reliance aims to permit Australia to conduct defensive operations in the event of low/medium level threats without depending immediately on its allies. This is to be achieved through the technological sophistication of defence equipment, a highly professional but small defence force and local industry support.

The burden of defence, measured as the share of defence outlay in GDP declined from about 3% in 1971–72 to about 2.3% in 1993–94. It has been the Government's policy to encourage the development of local defence‐related industry, in particular in areas such as: electronics/optics; communications and information technology; aerospace; shipbuilding and repair, munitions; and land vehicles. However, defence procurement has a small impact on the Australian economy as a whole.  相似文献   
784.
Developments within the UK in the Ministry of Defence’s policy on defence equipment acquisition demand changes in the scale and allocation of the Ministry’s budget for defence research. To facilitate the national debate on those changes, this paper reviews the key questions about UK defence research which the Ministry must resolve in order to implement its new Defence Technology Strategy.  相似文献   
785.
The 17th Conference of the Parties (COP17) had been anticipated as the ‘African COP’, not only due to the African venue but also due to the opportunity it would afford African countries – with South Africa at the helm – to steer the debate on a global climate change regime. With the conference now over, lobby groups, international organisations, negotiators, observers and commentators alike have been taking stock of its outcome. Despite the litany of developmental and security implications of climate change, COP17 got underway with little hope that much might actually be achieved. In light of the discouraging condition of the global economy, with leading developed economies suffering financially, states were hardly in a mood to be making concessions that would impact their fiscal health. Nonetheless, an agreement was reached. Questions remain, however, about the significance of the outcome of the African COP for the world at large, but ultimately also for Africa.  相似文献   
786.
In 2003, the Albanian government declared that in late 2002 it had discovered a heretofore unknown cache of 16 tons of chemical weapons. Tirana requested and received assistance from the West in securing and destroying the materials, a task completed in 2007. Albania has been lauded for its responsible handling of the discovery and for being the first nation to complete the destruction of its chemical weapons under the terms of the Chemical Weapons Convention (CWC). This article argues that the Albanian government has always knowingly possessed the weapons, keeping them a secret until a post-September 11, 2001 international focus on weapons of mass destruction made it politically worthwhile for Tirana to declare and destroy them. The likelihood that the governments of the West turned a willful blind eye to this chain of events is troubling for the credibility of the CWC and confidence in nonproliferation measures in general. Finally, the author recommends measures to avoid and address similar situations in the future.  相似文献   
787.
采用胞外聚合物作为生物絮凝剂,开展胞外聚合物复合絮凝剂强化混凝处理微污染原水的研究.研究结果表明,蛋白质是胞外聚合物最主要的成分,多糖次之,腐殖酸和脱氧核糖核酸的含量最低;胞外聚合物含有大量带负电荷的官能团,单独投加胞外聚合物不能有效絮凝和吸附去除原水中的污染物.聚合氯化铝混凝处理微污染水的效果优于氯化铝和聚合硫酸铁,药品较优投加质量浓度为70~80 mg/L.胞外聚合物和聚合氯化铝复合使用能提高对细小颗粒物的去除效果,增强去除有机污染物和氯化消毒副产物前驱体的能力,降低聚合氯化铝的质量浓度.胞外聚合物复合絮凝剂的较优配方:胞外聚合物质量浓度为5 mg/L,聚合氯化铝质量浓度为60 mg/L.  相似文献   
788.
Unpredictable disruptive events significantly increase the difficulty of the management of automobile supply chains. In this paper, we propose an automobile production planning problem with component chips substitution in a finite planning horizon. The shortage of one chip can be compensated by another chip of the same type with a higher-end feature at an additional cost. Therefore, the automobile manufacturer can divert the on-hand inventory of chips to product lines that are more profitable in the event of shortages caused by supply chain disruptions. To cope with this, we propose a max-min robust optimization model that captures the uncertain supplies of chips. We show that the robust model has a mixed-integer programming equivalence that can be solved by a commercial IP solver directly. We compare the max-min robust model with the corresponding deterministic and two-stage stochastic models for the same problem through extensive numerical experiments. The computational results show that the max-min robust model outperforms the other two models in terms of the average and worst-case profits.  相似文献   
789.
针对团装备保障层次设置模式优选时缺乏定量分析的问题,运用信息熵理论,建立了相应拓扑结构的时效和质量结构熵模型,尝试对团装备保障层次设置的组织结构有序度进行客观评价,为团装备保障层次设置模式的选择提供科学依据。  相似文献   
790.
论述了保障效能及其评估的内涵,按照能力-性能-特性的思路,建立了科学合理的装备保障效能评估指标体系,给出了定量定性指标构建效用函数的方法,建立出装备保障效能评估的数学模型,并应用具体实例进行了验证。  相似文献   
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