黄土丘陵区纸坊沟流域近70年农业生态安全评价

在国内外已有研究的基础上,结合黄土丘陵区纸坊沟流域近70a来农业生态经济系统演变过程,参考PSR模型,从生态环境、社会经济和综合功能3方面构建黄土丘陵区流域农业生态安全评价指标体系,基于层次分析法赋权的综合指数评价方法,对纸坊沟流域1938～2005年农业生态安全状况进行评价。结果表明:该流域农业生态安全状况发生了先降后升的变化,1938年处于较安全状况,1958年为极不安全状况,1975年和1985年都处于较不安全状况,1995年处于临界安全状况,2005年属于较安全状况。评价结果表明纸坊沟流域还需要进一步优化农业系统结构,实现农业生态安全。

黄海海域前新生代残留盆地综合地质地球物理研究

China’s annual oil import volume has been increasing in recent years, but the oil price in the international market fluctuates and poses a severe threat to China’s economic development and national security. Therefore, it is of great importance to study the gas and oil exploration of Pre-Cenozoic Residual Basins in Yellow Sea. Yellow Sea has widespread and thick Mesozoic and Paleozoic strata that contain multilayer source rock. Hence, Yellow Sea Mesozoic and Paleozoic strata have good conditions of forming Pre-Cenozoic hydrocarbon reservoirs. Pre-Cenozoic Residual Basins are usually buried deep and then transformed many times in its long evolutional history. These characteristics make it difficult to apply a single method in exploring Pre-Cenozoic Residual Basins. On the other hand, it is highly effective to solve key problems of gas and oil exploration of Pre-Cenozoic Residual Basins in Yellow Sea by using integrated geological and geophysical methods which make full use of the advantages of various exploring techniques. Based on the principle of “the region controls the local; the deep restricts the shallow,” this study focuses on Pre-Cenozoic Residual Basins in Yellow Sea to describe the structure frame of its distribution, with gravity, magnetic, seismic, drill-hole and geological data and previous research findings. In addition, the distribution characteristics of Pre-Cenozoic Residual Basins in Yellow Sea are also analyzed. This paper explores the characteristics of error between gravity forward with constant density and gravity forward with variable density through the study on 2-D and 3-D gravity forward in frequency domain. The result shows that there is a linear relationship between error and depth of 2-D geological model but there is a nonlinear relationship between error and depth of 3-D geological model. The error can be removed according to its linear characteristics or statistical nature of nonlinear characteristics. There is also error between gravity inversion with constant density and gravity inversion with variable density due to variable density and edge-effect. Since there are not noticeable rules between the error and the two causes as variable density and edge-effect, this study adopts gravity inversion with variable density and methods to eliminate the edge-effect in basement inversion to improve inversion accuracy. Based on the study on the rock physical properties and strata distribution of Yellow Sea and adjacent regions, this study finds that there is a big density contrast between Cretaceous-Jurassic strata and their substratum. The magnetic basement of south Yellow Sea is regarded as top of Archeozoic-Proterozoic early strata, and there are double magnetic basements in north Yellow Sea. Gravity and magnetic data are used to inverse the gravity basement and magnetic basement of Yellow Sea, with seismic and drill-hole data as constrains. According to data of gravity and magnetic basement distribution, the depth of Cenozoic strata and previous research findings, this paper calculates the thickness of the Mesozoic and Pre-Mesozoic Residual Basins, draws the distribution outline of Pre-Cenozoic Residual Basins in Yellow Sea, and analyzes its macro-distribution characteristics. Gravity inversion is applied on a typical geological profile in Yellow Sea to analyze the characteristics of its fractures and magnetic basements. The characteristics of Pre-Cenozoic Residual Basins distribution outline in Yellow Sea and the fractures and magnetic basements of its typical profile shown by profile inversion provides new geophysical evidence for these structure views such as “the South Yellow Sea and the North Yellow Sea belong to different structural units” and “Sino-Korea and Yangtze blocks combine along Yellow Sea East Fractured Zone in Yellow Sea”.

The Scientist Who Came in from the Cold: Heinz Barwich's Flight from the GDR

Maddrell, John, 'The Scientist Who Came in from the Cold: Heinz Barwich's Flight from the GDR', Intelligence and National Security (2005) 20(4) pp.608-630 RAE2008

The Study of Intelligence in Theory and Practice

Scott, Len, and Peter Jackson, 'The Study of Intelligence in Theory and Practice', Intelligence and National Security, (2004) 19(2) pp.139-169 RAE2008

Secret Intelligence, Covert Action and Clandestine Diplomacy

Scott, L. (2004). Secret Intelligence, Covert Action and Clandestine Diplomacy. Intelligence and National Security. 19(2), pp.322-341 RAE2008

Small Depth Quantum Circuits

Small depth quantum circuits have proved to be unexpectedly powerful in comparison to their classical counterparts. We survey some of the recent work on this and present some open problems.

A new world a new American foreign policy: the Carter administration, Nicaragua, and the legacy of the Vietnam War, 1977-1981

The impact of the Vietnam War conditioned the Carter administration’s response to the Nicaraguan revolution in ways that reduced US engagement with both sides of the conflict. It made the countries of Latin America counter the US approach and find their own solution to the crisis, and allowed Cuba to play a greater role in guiding the overthrow of Nicaraguan dictator Anastasio Somoza Debayle. This thesis re-evaluates Carter’s policy through the legacy of the Vietnam War, because US executive anxieties about military intervention, Congress’s increasing influence, and US public concerns about the nation’s global responsibilities, shaped the Carter approach to Nicaragua. Following a background chapter, the Carter administration’s policy towards Nicaragua is evaluated, before and after the fall of Somoza in July 1979. The extent of the Vietnam influence on US-Nicaraguan relations is developed by researching government documents on the formation of US policy, including material from the Jimmy Carter Library, the Library of Congress, the National Security Archive, the National Archives and Records Administration, and other government and media sources from the United Nations Archives, New York University, the New York Public Library, the Hoover Institution Archives, Tulane University and the Organization of American States. The thesis establishes that the Vietnam legacy played a key role in the Carter administration’s approach to Nicaragua. Before the overthrow of Somoza, the Carter administration limited their influence in Nicaragua because they felt there was no immediate threat from communism. The US feared that an active role in Nicaragua, without an established threat from Cuba or the Soviet Union, could jeopardise congressional support for other foreign policy goals deemed more important. The Carter administration, as a result, pursued a policy of non-intervention towards the Central American country. After the fall of Somoza, and the establishment of a new government with a left wing element represented by the Sandinistas, the Carter administration emphasised non-intervention in a military sense, but actively engaged with the new Nicaraguan leadership to contain the potential communist influence that could spread across Central America in the wake of the Nicaraguan revolution.

Justifying jihad: US politics, propaganda and the Afghan mujahedeen

Hard-line anti-communists in the United States recognised the potential for the Soviet invasion of Afghanistan in 1979 to embroil their super-power rival in a ‘Vietnam-like quagmire.’ Their covert operation to arm the mujahedeen is well documented. This dissertation argues that propaganda and public diplomacy were powerful and essential instruments of this campaign. It examines the protagonists of this strategy, their policies, initiatives and programmes offering a comprehensive analysis heretofore absent. It stretches from the dying days of the Carter administration when Zbigniew Brzezinski saw the ‘opportunity’ presented by the invasion to the Soviet’s withdrawal in 1989. The aim of these information strategies was to damage Soviet credibility and enhance that of the US, considered under threat from growing ‘moral equivalence’ amongst international publics. The conflict could help the US regain strategic advantage in South Asia undermined by the ‘loss’ of Iran. The Reagan administration used it to justify the projection of US military might that it believed was eviscerated under Carter and emasculated by the lingering legacy of Vietnam. The research engages with source material from the Reagan Presidential Library, the United States Information Agency archives and the Library of Congress as well as a number of online archives. The material is multi-archival and multi-media including documentaries, booklets, press conferences, summit programmes and news-clips as well as national security policy documents and contemporaneous media commentary. It concludes that propaganda and public diplomacy were integral to the Reagan administration and other mujahedeen supporters’ determination to challenge the USSR. It finds that the conflict was used to justify military rearmament, further strategic aims and reassert US power. These Cold War machinations had a considerable impact on the course of the conflict and undermined efforts at resolution and reconciliation with profound implications for the future stability of Afghanistan and the world.

Design and Emergence in the Making of American Grand Strategy

The main research question of this thesis is how do grand strategies form. Grand strategy is defined as a state's coherent and consistent pattern of behavior over a long period of time in search of an overarching goal. The political science literature usually explains the formation of grand strategies by using a planning (or design) model. In this dissertation, I use primary sources, interviews with former government officials, and historical scholarship to show that the formation of grand strategy is better understood using a model of emergent learning imported from the business world. My two case studies examine the formation of American grand strategy during the Cold War and the post-Cold War eras. The dissertation concludes that in both these strategic eras the dominating grand strategies were formed primarily by emergent learning rather than flowing from advanced designs.

China's Sovereign Wealth Funds: Problem or Panacea?

China’s impressive economic growth has led to the accumulation of massive financial assets. The emergence of sovereign wealth funds (SWFs), as a governmental investment device for its excessive foreign reserves, symbolizes a major rebalancing of economic power. With its investment portfolios drastically diversified for well-established financial institutions as well as some strategic sectors, a seminal debate seems centered on whether China’s SWFs are in furtherance of purely commercial or geopolitically strategic purposes. Under the sophisticated hard laws associated with international initiatives, it is unlikely that the SWFs-related investment would distort the global financial system, and genuinely threaten national security, which assumption may only exist at a hypothetical level. The potential protectionism would inevitably retard the world economy’s recovery, were it not to be proportionately addressed. A most significant necessity appears to be to strike a proportionate balance between sustaining the credibility of open investment environment and efficiently minimizing implications of SWFs political arenas.

Overcoming the Scalability Challenges of Epidemic Simulations on Blue Waters

Modeling dynamical systems represents an important application class covering a wide range of disciplines including but not limited to biology, chemistry, finance, national security, and health care. Such applications typically involve large-scale, irregular graph processing, which makes them difficult to scale due to the evolutionary nature of their workload, irregular communication and load imbalance. EpiSimdemics is such an application simulating epidemic diffusion in extremely large and realistic social contact networks. It implements a graph-based system that captures dynamics among co-evolving entities. This paper presents an implementation of EpiSimdemics in Charm++ that enables future research by social, biological and computational scientists at unprecedented data and system scales. We present new methods for application-specific processing of graph data and demonstrate the effectiveness of these methods on a Cray XE6, specifically NCSA's Blue Waters system.

Distribution of Uranium and Thorium in Dolomitic Gravel Fill and Shale Saprolite

The objectives of this study were to examine (1) the distribution of U and Th in dolomitic gravel fill and shale saprolite, and (2) the removal of uranium from acidic groundwater by dolomitic gravel through precipitation with amorphous basaluminite at the U.S. DOE Oak Ridge Integrated Field Research Challenge (ORIFRC) field site west of the Oak Ridge Y-12 National Security Complex in East Tennessee. Media reactivity and sustainability are a technical concern with the deployment of any subsurface reactive media. Because the gravel was placed in the subsurface and exposed to contaminated groundwater for over 20 years, it provided a unique opportunity to study the solid and water phase geochemical conditions within the media after this length of exposure. This study illustrates that dolomite gravel can remove U from acidic contaminated groundwater with high levels of Al3+, Ca2+, NO3−, and SO42− over the long term. As the groundwater flows through high pH carbonate gravel, U containing amorphous basaluminite precipitates as the pH increases. This is due to an increase in groundwater pH from 3.2 to ∼6.5 as it comes in contact with the gravel. Therefore, carbonate gravel could be considered as a possible treatment medium for removal and sequestration of U and other pH sensitive metals from acidic contaminated groundwater. Thorium concentrations are also high in the carbonate gravel. Thorium generally shows an inverse relationship with U from the surface down into the deeper saprolite. Barite precipitated in the shallow saprolite directly below the dolomitic gravel from barium present in the acidic contaminated groundwater.

The Climate of War: Violence, Warfare and Climatic Reductionism

National security agencies and other interested parties now often regard conflict as the inevitable consequence of climate change. This inclination to reduce war to the vicissitudes of climate is not new however. Here I examine some of the earlier ways in which violence was attributed to climatic conditions, particularly in the United States, and trace links between these older advocates of climatic determinism and the recent writings of those insisting that climate change will usher in a grim world of chronic warfare. It ends by drawing attention to the writings of some critics who are troubled by the ease with which climatic reductionism is capturing the public imagination.