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441.
This article generalizes the dynamic and stochastic knapsack problem by allowing the decision‐maker to postpone the accept/reject decision for an item and maintain a queue of waiting items to be considered later. Postponed decisions are penalized with delay costs, while idle capacity incurs a holding cost. This generalization addresses applications where requests of scarce resources can be delayed, for example, dispatching in logistics and allocation of funding to investments. We model the problem as a Markov decision process and analyze it through dynamic programming. We show that the optimal policy with homogeneous‐sized items possesses a bithreshold structure, despite the high dimensionality of the decision space. Finally, the value (or price) of postponement is illustrated through numerical examples. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 267–292, 2015  相似文献   
442.
Isabelle Côté 《Civil Wars》2015,17(3):357-378
Why are large population movements conflict-prone in some regions while they remain peacefully integrated elsewhere? I argue that clashes between ethnically distinct indigenous populations and migrants – i.e. ‘Sons of the Soil (SoS) conflict’ – erupt when there are large socio-economic and political horizontal inequalities between ‘dominant migrants’ and locals. A comparative case study of two Chinese minority regions based on ethnographic fieldwork and population data provides a vivid illustration of the mechanisms linking migration to SoS conflict. With fewer HIs between migrants and locals, Inner Mongolia avoided many of the violent clashes that were commonplace in Qinghai, a province fraught with disparities.  相似文献   
443.
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   
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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   
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SHADOW WARS     
The Secret War with Iran: The 30-Year Clandestine Struggle Against the World's Most Dangerous Terrorist Power, by Ronen Bergman. Free Press, 2008. 432 pages, $28

Fallout: The True Story of the CIA's Secret War on Nuclear Trafficking, by Catherine Collins and Douglas Frantz. Free Press, 2011. 304 pages, $26.

The Twilight War: The Secret History of America's Thirty-Year War with Iran, by David Crist. Penguin Press, 2012. 638 pages, $36.

Israel vs. Iran: The Shadow War, by Yaakov Katz and Yoaz Hendel. Potomac Books Inc., 2012. 254 pages, $30.

Spies Against Armageddon: Inside Israel's Secret Wars, by Dan Raviv. Levant, 2012. 356 pages, $17.

Confront and Conceal: Obama's Secret Wars and Surprising Use of American Power, by David E. Sanger. Crown Publishers, 2012. 476 pages, $28.  相似文献   
450.
BUSTING OUT     
This report explores Iranian popular opinion on the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) and the determinants of Iranian attitudes. Using data from a 2008 survey of 710 Iranians administered by the University of Maryland's Program on International Policy Attitudes, we find that that a significant minority of Iranians (10 percent in 2006 and 14 percent in 2008) would prefer that Iran withdraw from the NPT. Our statistical analysis shows that Iranians who fear a US attack on Iranian nuclear facilities and distrust the International Atomic Energy Agency are more likely to want to quit the NPT. We therefore argue that those who do not trust other nations are most likely to oppose the NPT.  相似文献   
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