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581.
A general model for the failure of fibrous composite materials is described. It is shown to contain some of the well-known models in the literature. The composite material is viewed as a coherent system of independent identically distributed component strengths. Under the assumption that the applied load is redistributed “homotonically” to the unfailed components upon the failure of a component (an individual fiber segment) and that the distributions of component strengths are IFRA, it is shown that the system (composite) strength distribution is also IFRA. Examples are given using carbon reinforced composite data to illustrate the IFRA property.  相似文献   
582.
This article further considers the two‐person continuous ambush game introduced by Ruckle. This article extends the work of Ruckle, Baston and Bostock, and Lee by considering the game for a general number of barriers. By supplanting optimal strategies from a discretized version of the game, we show that there always exists a value for the game, which, furthermore, can be found using linear programming techniques. Further to this, we show that the discrete ambush game considered by Garnaev has the same value as a continuous game, allowing many new results to be obtained in both games. © 2003 Wiley Periodicals, Inc. Naval Research Logistics 50: 515–529, 2003  相似文献   
583.
We investigate a single‐machine scheduling problem for which both the job processing times and due windows are decision variables to be determined by the decision maker. The job processing times are controllable as a linear or convex function of the amount of a common continuously divisible resource allocated to the jobs, where the resource allocated to the jobs can be used in discrete or continuous quantities. We use the common flow allowances due window assignment method to assign due windows to the jobs. We consider two performance criteria: (i) the total weighted number of early and tardy jobs plus the weighted due window assignment cost, and (ii) the resource consumption cost. For each resource consumption function, the objective is to minimize the first criterion, while keeping the value of the second criterion no greater than a given limit. We analyze the computational complexity, devise pseudo‐polynomial dynamic programming solution algorithms, and provide fully polynomial‐time approximation schemes and an enhanced volume algorithm to find high‐quality solutions quickly for the considered problems. We conduct extensive numerical studies to assess the performance of the algorithms. The computational results show that the proposed algorithms are very efficient in finding optimal or near‐optimal solutions. © 2017 Wiley Periodicals, Inc. Naval Research Logistics, 64: 41–63, 2017  相似文献   
584.
585.
An increasing number of countries recognize the special risks of nuclear terrorism associated with the civilian use and storage of and commerce in highly enriched uranium (HEU). They are especially concerned that non-state actors might gain access to HEU and use it to build and detonate improvised nuclear devices. The risk is aggravated by the very large global stocks of HEU, some of which are inadequately protected. Although HEU has few commercial uses, and most experts believe it is technically feasible to substitute low-enriched uranium for HEU in nearly all civilian applications, efforts to reduce HEU stocks have been impeded by a variety of economic, political, and strategic considerations. This article analyzes the nature of these impediments and discusses what is required to overcome them.  相似文献   
586.
For a three‐sector Feder‐Ram framework, we present time‐series, cross‐sectional estimates for two cohorts, consisting of Asian and Latin American countries. The estimates indicate that private investment, and defense and non‐defense public spending are growth promoting for alternative error components representations. For the best error components representation, greater growth enhancement is associated with the two forms of public spending in Asia than in Latin America, while the opposite comparison characterizes private investment. Although defense is growth promoting, an opportunity cost exists insofar as non‐defense spending, financed by defense spending, appears to give a small net boost to growth in Latin America.  相似文献   
587.
After a brief survey of the Indian economy, we survey the supply and demand of military expenditures in India over the last four decades. The causes of military expenditures appear to include regional rivalries and protracted conflicts, but it has proven difficult to delineate these with empirical models. The effects of military spending in India on economic growth appear to be benign, despite much speculation to the contrary. However, the opportunity costs of defence spending are shown to be considerable. We conclude with speculation about the role of debt and debt servicing in retarding future economic growth in India. We also speculate about the potential for the creation of a war economy in India.  相似文献   
588.
It came as a surprise to many international observers when, on 31 March 2005, the United Nations Security Council passed resolution 1593, which referred the situation in Darfur to the jurisdiction of the International Criminal Court. Some celebrated this event as initiating a new era in which international criminal justice would prevail, but they might have done well to consider the objections immediately raised by the representatives of the Sudanese government, which was not a party to the ICC, a point that created a series of impediments to the implementation of the resolution. For all that the ICC has been charged with investigating crimes against humanity in Darfur, its investigators are being prevented from seeking the evidence on the ground essential to any successful prosecution. The Sudanese government has so far maintained its obstructive position, arguing that it is capable of handling such cases within its own sovereign jurisdiction. The imperative of excluding the ICC from Darfur has contributed to Khartoum's objections to the deployment of a UN force to replace the African Union mission there. In sum: the challenges faced by the ICC in Darfur demonstrate that international criminal justice does not operate in a political vacuum.  相似文献   
589.
This article assesses South Africa's 20 years of democracy, which has frequently been bedevilled by local protests. This article is particularly interested in those unrest incidents that have been distinct for one reason or another. In South Africa, the surge in local unrest incidents is often linked to police behaviour, which has become increasingly militant and brutal when quelling protests. While the right to protest is constitutional, the damage caused during protest action can be immense owing to acts of violence. Protestors' resorting to violent protest action is often linked to increased frustrations as a result of the government's inability to live up to the expectations of marginalised and poor communities. While this article draws primarily on existing scholarly debates focusing on social protests, the primary objective is to examine the impact of unrest incidents on local protests in post-apartheid South Africa. The article further argues that ‘spaces’ for participation in local governance should be created so that citizens can become architects of development and their own future.  相似文献   
590.
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