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This paper re-examines the long-run causal relationship between military expenditure and economic growth in China over the period 1952–2010. An empirical econometric analysis based on a Barro-style growth model is conducted. By employing the Bartlett corrected trace test, which provides better approximations of the finite sample distribution to determine the rank of cointegration, the results support the existence of a single long-run equilibrium relationship between the variables. Furthermore, it is confirmed that the cumulated shocks of military expenditure primarily originate from different components of shocks that relate to economic development rather than the other way round.  相似文献   
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This paper addresses the routing problem with reliability requirements in packet-switched communication networks. In this problem, two classes of communicating node pairs are considered: less critical and highly critical node pairs. We develop a model which identifies a primary route for each less critical node pair and both a primary and a secondary (back up) route for each highly critical node pair. The objective is to minimize the average delay encountered by messages. A solution procedure based on a relaxation of the problem is presented. Computational results over a wide range of problem structures show that the procedure is very effective. © 1997 John Wiley & Sons, Inc. Naval Research Logistics 44 : 485–505, 1997  相似文献   
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In this article, we define a scheduling/packing problem called the Job Splitting Problem, motivated by the practices in the printing industry. There are n types of items to be produced on an m‐slot machine. A particular assignment of the types to the slots is called a “run” configuration and requires a setup cost. Once a run begins, the production continues according to that configuration and the “length” of the run represents the quantity produced in each slot during that run. For each unit of production in excess of demand, there is a waste cost. Our goal is to construct a production plan, i.e., a set of runs, such that the total setup and waste cost is minimized. We show that the problem is strongly NP‐hard and propose two integer programming formulations, several preprocessing steps, and two heuristics. We also provide a worst‐case bound for one of the heuristics. Extensive tests on real‐world and randomly generated instances show that the heuristics are both fast and effective, finding near‐optimal solutions. © 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010  相似文献   
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Policy makers and scholars have drawn improper lessons from the Ukrainian case of disarmament. Employing a content analysis of Ukrainian and Russian news sources, as well as a series of interviews with Ukrainian officials conducted by the author, this paper argues that Ukraine did not surrender its nuclear arsenal because it received compensation or faced financial and technical hurdles in securing effective command and control over the weapons. Instead, Ukraine surrendered its nuclear weapons due to a lack of demand for them. The historical interactions between Ukrainians and Russians led the majority of Ukrainian leaders to reject a conception of the Ukrainian national identity that cognitively perceived Russia as a security threat. Only with a proper understanding of this case study can the international community understand how the nonproliferation norm succeeded.  相似文献   
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The bending and stress analysis of a functionally graded polymer composite plate reinforced with gra-phene platelets are studied in this paper. The governing equations are derived by using principle of virtual work for a plate which is rested on Pasternak's foundation. Sinusoidal shear deformation theory is used to describe displacementfield. Four different distribution patterns are employed in our analysis. The analytical solution is presented for a functionally graded plate to investigate the influence of important parameters. The numerical results are presented to show the deflection and stress results of the problem for four employed patterns in terms of geometric parameters such as number of layers, weight fraction and two parameters of Pasternak's foundation.  相似文献   
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Ceramic reinforced metal matrix nanocomposites are widely used in aerospace and auto industries due to their enhanced mechanical and physical properties. In this research, we investigate the mechanical properties of aluminum/Nano-silica composites through experiments and simulations. Aluminum/Nano-silica composite samples with different weight percentages of silica nanoparticles are prepared via powder metallurgy. In this method, Nano-silica and aluminum powders are mixed and compressed in a mold, followed by sintering at high temperatures. Uniaxial tensile testing of the nanocomposite samples shows that adding one percent of Nano-silica causes a considerable increase in mechanical properties of nanocomposite compared to pure aluminum. A computational micromechanical model, based on a representative volume element of aluminum/silica nanocomposite, is developed in a commercial finite element software. The model employs an elastoplastic material model along with a ductile damage model for aluminum matrix and linear elastic model for nano-silica particles. Via careful determination of model parameters from the experimental results of pure aluminum samples prepared by powder metallurgy, the proposed computational model has shown satisfactory agreement with experiments. The validated computational model can be used to perform a parametric study to optimize the micro-structure of nanocomposite for enhanced mechanical properties.  相似文献   
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The United States has conducted armed drone strikes in Pakistan since 2004. While there has been some recent work on Pakistani public opinion about drones, there is very little research on how Pakistan’s media characterize the US drone program. This is an important gap in understanding the determinants of Pakistani popular perceptions of this program. Decades of research has shown that “news framing”, a process by which certain aspects of a complex concept are emphasized in political communications with others played down, influences individual cognition while forming political opinions. In this essay, we address this lacuna by assembling an unprecedented sample of editorials about the drone program from three English newspapers and one Urdu newspaper and analyzing the news frames within them. We next compare the trends in these news frames to public opinion data collected by Pew between the spring of 2009 and 2014. Initially, most Pakistanis were unaware of the drone program, media coverage of the program expanded as drone strikes increased in frequency. While Pakistanis became more cognizant of the US drone strikes, even by 2014 large minorities remained unaware. Pakistani public opinion strongly reflected the top media frames, particularly those that are negative. This is an important finding suggesting that newspaper editorials are a good barometer of Pakistani opinions despite the fact that only information elites rely upon newspapers for political information.  相似文献   
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