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91.
关于(S)_+型映射的一个区域不变定理及其应用   总被引:1,自引:0,他引:1  
本文运用拓扑度方法,获得一个关于(S)_+型映射的区域不变定理。作为它的应用,本文得到了扩张映射的满值性,从而部分地回答了著名数学家L.Nirenberg提出的一个关于扩张映射满值性的公开问题。  相似文献   
92.
Hungary, a former communist state, adapted a Western-style defense planning system during the 1990s and 2000s. Although on the surface the elements of this planning system were similar to the planning programming budgeting system (PPBS) developed by the US Department of Defense, strategic guidance for defense planning has not been properly developed until recently. Thus, albeit PPBS-based defense plans were developed in the Hungarian Ministry of Defense (Hungarian MoD) regularly, they lacked both an expression of clear priorities and strategic focus. This article delineates the evolution of strategic guidance in the Hungarian MoD concentrating on current developments, and introduces the newly elaborated analytical concepts and tools, which helped to create needed strategic guidance in Hungary.  相似文献   
93.
‘Mowing the Grass’, Israel’s strategy in the twenty-first century against hostile non-state groups, reflects the assumption that Israel finds itself in a protracted intractable conflict. The use of force in such a conflict is not intended to attain impossible political goals, but a strategy of attrition designed primarily to debilitate the enemy capabilities. Only after showing much restraint in its military responses does Israel act forcefully to destroy the capabilities of its foes, hoping that occasional large-scale operations also have a temporary deterrent effect in order to create periods of quiet along its borders. The Israeli approach is substantively different from the current Western strategic thinking on dealing with non-state military challenges.  相似文献   
94.
The U.S. Congress, charged with overseeing U.S. nuclear weapons policy and programs, usually addresses such policies and programs through the annual authorization and appropriations process, focusing mostly on questions of how many and what types of weapons the United States should deploy, with little attention paid to questions about nuclear weapons strategy, doctrine, and policy. The oversight process has brought about some significant changes in the plans for U.S. nuclear weapons, including the elimination of funding for the Robust Nuclear Earth Penetrator study and the shift of that funding into a study of the Reliable Replacement Warhead. But with the focus on authorizations and appropriations, along with the divided jurisdiction over nuclear weapons policy and programs in congressional committees, Congress has not, either recently or during the Cold War and post–Cold War eras, conducted a more comprehensive review of U.S. nuclear weapons strategy, policy, or force structure. Changes in committee jurisdictions could affect the oversight process, but as long as nuclear weapons policy and programs remain a relatively low priority for most members of Congress, and the country at large, it is unlikely that Congress will pursue such a comprehensive debate.  相似文献   
95.
U.S. nuclear export policy has undergone major transformations since 1945, and the most recent change, as expressed in the July 18, 2005, India-U.S. Joint Statement, represents an especially significant shift in policy. The document reverses more than a quarter century of U.S. declaratory policy, suggesting that the current U.S. administration regards nuclear proliferation to be both inevitable and not necessarily a bad thing. This article investigates this policy shift, looking at the history of U.S. nuclear export policy and the potential ramifications of the new policy on the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). The author also touches on the potential effects of the Joint Statement on Indian-Pakistani relations. Finally, it is suggested that it is not too late for India and the United States to change the new policy with more consideration for the NPT and the Nuclear Suppliers Group Initiative.  相似文献   
96.
One of the most important questions affecting U.S. national security is the future size of the U.S. nuclear stockpile. While there is clear consensus within the U.S. government on the need to reduce the size of the arsenal, there is none on the best path to achieve these cuts; on the type of deterrent necessary to deal with future threats; or on the size of the production complex needed to support that arsenal. Creating a strategic commission to review these questions, as contemplated in the Fiscal 2008 House Defense Authorization bill, is a necessary first step to establish a sensible nuclear policy. The Reliable Replacement Warhead, which has the potential to transform the complex while preserving the current moratorium on nuclear testing, is a program worth exploring further if it stays within congressionally mandated bounds. As Congress considers both programmatic and policy matters related to U.S. nuclear weapons, it is vital that we also renew and strengthen U.S. leadership on nuclear nonproliferation.  相似文献   
97.
郭俊 《国防科技》2013,(6):73-75,88
2013年5月29日,美军参联会发布新版《太空作战》联合条令。文章对新版条令的主要内容进行了概括,对新、旧版本条令的差异进行了分析研究。  相似文献   
98.
This paper models the space race between the US and the Soviet Union during the Cold War using time series econometric modelling. The analysis shows that, post the Vietnam‐war era, military considerations play a key role in explaining the behaviour of US space expenditure. In particular, the US Department of Defense (DoD) Strategic Defense Initiative (SDI) of the early 1980s is shown to result in a changing structure of the space race. This is expected to continue in the future with the current anti‐ballistic missile (ABM) programme and the withdrawal of the US from the ABM treaty of on space militarization.  相似文献   
99.
This paper develops and implements a methodology for quantifying defense conversion in Russian manufacturing in the early 1990s. A two‐sector, three‐good model is employed to analyze the flows of resources from military to non‐military uses and applied to firm‐level survey data under alternative definitions of military production and the MIC. An aggregation framework is constructed to estimate the total quantity and change in Russian military production, the latter decomposed into intrafirm and intersectoral resource reallocation and overall industrial decline. Although there is evidence of substantial decline in military production, the data show little reallocation to productive civilian uses, neither within the MIC nor to other manufacturing sectors.  相似文献   
100.
A recent paper in Defence Economics suggests that “a single variable, the public opinion balance, ... when accompanied by a control variable measuring the proportion of responses in the ‘residuum’ (no opinion or keep the status quo), permits an accurate prediction of subsequent changes in the rate of change of U.S. defense outlays from the mid‐1960s through the 1980s” (Higgs and Kilduff, 1993, p. 227). In contrast, this comment provides evidence that since 1986 the Higgs‐Kilduff model frequently mispredicts the direction of U.S. defense spending. In addition, the average prediction error, and its variance, since 1986 consistently exceeds the average prediction error, and its variance, for the years prior to 1986.  相似文献   
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