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151.
Gerhard Kümmel 《战略研究杂志》2013,36(2):7-28
The debate on the civil–military gap and especially the TISS findings are viewed with a focus on Germany. After outlining the historical development of civil–military relations, the question of a civil–military gap is explored with data from 2001. The study finds similarities and differences in the attitudes of the civilian and the military population on several issues. Overall, there is a broad overlap of attitudes, yet differences do exist, especially on issues of foreign policy and things military. It is argued that at the beginning of the twenty-first century, civil–military relations in Germany are largely uncontested, but will become more strained. 相似文献
152.
Daniel R. Green 《Small Wars & Insurgencies》2013,24(4):591-609
The successful pacification of Fallujah in 2007 during the Anbar Awakening movement was due to the coordinated efforts of US and Iraqi forces to physically and psychologically separate the people from the insurgency. Efforts along security, political, and development lines along with a robust tribal effort eliminated the armed insurgency and set the basis for victory in the area. But a synchronized delivery of these resources was insufficient to defeat the insurgency by itself absent the population's decision to turn against the insurgents. This process began to occur in 2006 and was successfully capitalized upon by Coalition Forces in Fallujah in 2007. 相似文献
153.
Kavita Ghosh L.V. Gaikwad R.K. Kalal P.A. Kulkarni Arvind Kumar Shaibal Banerjee Manoj Gupta 《防务技术》2021,17(2):559-570
In the present study,organically modified Montmorillonite clay with polar moiety,the Cloisite 30B,is used for preparation of Hydroxyl terminated polybutadiene(HTPB)-clay nanocomposites(HCN)by dispersion of nanoclay in polymer matrix under high shear mixing.The nanocomposites thus prepared are evaluated in composite propellants as inhibitor material for their functional utility.Several inhibition formulations containing 5 wt%-15 wt%of nanoclay,with or without the conventional filler Sb2O3,were prepared.All these formulations were evaluated for their physical,mechanical,thermal,and ablative properties.Ablation rate and density of the compositions containing Cloisite 30B is around 23%and 5%lower respectively in comparison of the base composition.Strain capability of these compositions is twofold higher than that of base composition.These compositions have also been evaluated for their smoke generation tendency by measuring infra red(IR)attenuation in the wavelength range 1.3 μm-5.6 μm and 8 μm-13 μm and thereby compared with the base composition.The corresponding results confirmed that the compositions containing Cloisite 30B as filler have much lower IR attenuation than compositions with conventional filler,Sb2O3.Replacement of 5%Sb2O3 by nanoclay showed 8%reduction in IR attenuation rate which further reduced to 16%on replacement of 15%of Sb2O3.Interfacial bonding of HCN based inhibitors is also comparable or even better than conventional inhibitors.Precisely,the nanoclay composites with Cloisite 30B as filler exhibit all desirable properties of an inhibitor. 相似文献
154.
Tungsten inert gas (TIG) welding is the most commonly used joining process for aluminum alloy for AA6061 and AA7075 which are highly demanded in the aerospace engineering and the automobile sector, but there are some defects occur during TIG welding like micro-crack, coarse grain structure, and porosity. To improve these defects, the TIG welded joint is processed using friction stir processing (FSP). This paper presents the effect of friction stir processing on TIG welding with filler ER4043 and ER 5356 for dissimilar aluminum alloy AA6061 and AA7075. The mechanical characterization, finite element formulation and mathematical equations of heat transfer of TIG + FSP welded joints are investigated using ANSYS Fluent software by adjusting process parameters of FSP. The results show that the maximum compressive residual stress 73 MPa was obtained at the fusion zone (FZ) of the TIG weldment with filler ER4043, whereas minimum compressive residual stress 37 MPa was obtained at stir zone (SZ) of the TIG+FSP with filler 5356. The maximum heat flux 5.33 × 106 W/m2 and temperature 515 ℃ have observed at tool rotation 1600 rpm with a feed rate of 63 mm/min. These results give a satisfactory measure of confidence in the fidelity of the simulation 相似文献
155.
Bayes假设检验及样本数量问题研究 总被引:1,自引:0,他引:1
针对Bayes方法在工程实践中未能得到广泛应用的实际情况分析了Bayes方法存在的问题,以正态总体期望为背景研究并改进了Bayes方法,进一步推导了Bayes假设检验样本数量确定方法。 相似文献
156.
In the last decade, there has been much progress in understanding scheduling problems in which selfish jobs aim to minimize their individual completion time. Most of this work has focused on makespan minimization as social objective. In contrast, we consider as social cost the total weighted completion time, that is, the sum of the agent costs, a standard definition of welfare in economics. In our setting, jobs are processed on restricted uniform parallel machines, where each machine has a speed and is only capable of processing a subset of jobs; a job's cost is its weighted completion time; and each machine sequences its jobs in weighted shortest processing time (WSPT) order. Whereas for the makespan social cost the price of anarchy is not bounded by a constant in most environments, we show that for our minsum social objective the price of anarchy is bounded above by a small constant, independent of the instance. Specifically, we show that the price of anarchy is exactly 2 for the class of unit jobs, unit speed instances where the finite processing time values define the edge set of a forest with the machines as nodes. For the general case of mixed job strategies and restricted uniform machines, we prove that the price of anarchy equals 4. From a classical machine scheduling perspective, our results establish the same constant performance guarantees for WSPT list scheduling. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012 相似文献
157.
采用MMW-1万能摩擦磨损试验机,考察了磨合预处理工况(时间、载荷)对两种有机钼添加剂在CF-4 15W-40柴油机油中抗磨减摩性能的影响。采用扫描电子显微镜和能谱仪分析了磨斑表面形貌和表面元素组成。结果表明,适当的磨合预处理可有效增强有机钼添加剂在柴油机油中的抗磨减摩性能,且经过磨合预处理的磨斑表面形貌较没有处理时平整,添加剂主要功能元素在摩擦表面的质量分数增加。 相似文献
158.
Without restricting the class of permissible schedules, we derive optimal schedules for economic lot scheduling problems that are fully loaded, have external setups, and have only two products. The fully loaded condition accurately represents certain types of bottlenecks. We show that the optimal schedule must have the Wagner-Whitin property. We also develop a measure of aggregate inventory, derive an optimal steady-state aggregate inventory policy, and provide conditions under which the aggregate inventory level of an optimal schedule must approach a steady state. By restricting the class of permissible schedules to rotation cycle schedules, we extend these results to more than two products. 相似文献
159.
A procedure for obtaining a facilities scatter diagram within a rectangular boundary is developed using a multifacility location model. This method gives favorable computational results and has the advantage over other scatter diagram methods of being able to accommodate fixed facility locations. Examples illustrate how this method can be used by a designer/analyst either as a one-step algorithm or iteratively to build a layout. 相似文献
160.
Let X be a positive random variable. The distribution F of X is said to be “new better than used in expectation,” or “NBUE,” if E(X) ⩾ E(X – t|X > t) for all t ⩾ 0. Suppose X1, …, Xn, is a random sample from an NBUE distribution F. The problem of estimating F by a distribution which is itself NBUE is considered. The estimator Gn, defined as the NBUE distribution supported on the sample which minimizes the (sup norm) distance between the NBUE class and the empirical distribution function, is studied. The strong uniform consistency of Gn, is proven, and a numerical algorithm for obtaining Gn, is given. Our approach is applied to provide an estimate of the distribution of lifetime following the diagnosis of chronic granulocytic leukemia based on data from a National Cancer Institute study. 相似文献