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121.
Book review     
Steven L. Burg and Paul S. Shoup, The War in Bosnia‐Herzegovina: Ethnic Conflict and International Intervention.New York: M.E. Sharpe, 1999. Pp.xviii + 499, maps, tables, notes, biobliog., index. NP. ISBN 1–56324–308–3.  相似文献   
122.
In Chechnya a protracted conflict only seemingly quieted down, but it still smolders and as the conflict is suppressed by coercion, it is inevitable that it will flare up at some time in the near future. The root causes of the conflict can be understood by use of globalization theory, which dialectically brings together the clashing forces from above and below. Civil society in Chechnya deteriorated, is politically curtailed, and has no resilience left. It thus results in a frozen conflict and an excluded and victimized society. Russian-style reconstruction does alleviate living conditions, but does not remediate the frozen conflict character of the present situation. The dynamics of the globalizing forces from below and above, summarized in the glocalization concept, not only explains the resistance by the Chechen people, for whom revolt, rebellion, and terrorism remain attractive options, but also serves as a model for other insurgencies. Reflecting on the two recent Chechen–Russian wars results in a paradigmatic case study.  相似文献   
123.
Based on the experience of the Cold War, some scholars hoped that the introduction of nuclear weapons into South Asia would promote peace between India and Pakistan. Instead, nuclear weapons made Pakistan less fearful of India's conventional military forces, and therefore help explain recent conflicts between them. Moreover, US expressions of concern about the possibility of inadvertent nuclear war in South Asia may have provided an incentive to both sides to be intransigent in order to elicit US intervention.  相似文献   
124.
125.
This article explores a perennial theme in the literature of strategic studies: the relationship between military theory and the military profession. It begins with a conceptual analysis of this relationship. It then investigates what military theorists themselves have had to say about the utility of their craft. It concludes by assessing the actual influence of military theory on selected individuals and institutions. The individuals are George S. Patton, Jr., and Ulysses S. Grant. The institutions are the United States Army and the United States Air Force in the late twentieth century. The fundamental finding is suggested in the title: military theory can indeed be quite useful in the maturation of military commanders and in the development of martial institutions, but it is not always necessary and by no means perfect. It should thus be studied assiduously but used with caution.  相似文献   
126.
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   
127.
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   
128.
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   
129.
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   
130.
The problem of searching for randomly moving targets such as children and submarines is known to be fundamentally difficult, but finding efficient methods for generating optimal or near optimal solutions is nonetheless an important practical problem. This paper investigates the efficiency of Branch and Bound methods, with emphasis on the tradeoff between the accuracy of the bound employed and the time required to compute it. A variety of bounds are investigated, some of which are new. In most cases the best bounds turn out to be imprecise, but very easy to compute. © 1998 John Wiley & Sons, Inc. Naval Research Logistics 45: 243–257, 1998  相似文献   
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