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1.
Energy continues to serve as the bedrock of modern economies and the main driver of modern society. For Africa, the production and supply of energy resources such as crude oil, natural gas, uranium, coal, biomass, biofuels and other renewables are an important source of employment, rents, taxes, royalties and profits. This sector brings in several tens of billions of dollars of revenue annually. The production and delivery of such resources, however, depend on critical infrastructures such as pipelines, refineries, processing plants, terminals, rigs, electrical energy pylons, substations, pump stations, vessels, and tankers. These infrastructures have been attacked by terrorists, insurgents, vandals and saboteurs, all of whom see them as targets against which to register their grievances and extract concessions from the state. This paper is a chronological account of some of the documented incidents of terrorism, insurgency, kidnapping, destruction, sabotage, and human casualties suffered in the oil and gas sectors in Africa between 1999 and 2012. It is based on data extracted from the databases of the RAND Database of World Terrorism Incidents and the University of Maryland's Global Terrorism Database (GTD).  相似文献   

2.
This article demonstrates the inconsistent and wavering Soviet attitude towards national liberation movements in general and the Palestinian organizations in particular. Until the late 1960s, the Soviets viewed these organizations with suspicion, hesitating to engage in political dialogue with them. However, in the 1970s, political and military events in the region, as well as modifications in the Kremlin's Cold War strategies, led to a general shift towards the Middle East in Soviet foreign policy. Soviet leaders showed increased willingness to provide certain Palestinian organizations with arms with which to conduct terrorist activities against Israeli, pro-Israeli, Jewish and Western targets. The article explores the complex relations between Palestinian organizations and the USSR in the field of international terror. The study also exposes and analyzes the nature and content of Soviet–Palestinian arms dialogues and transactions. It provides clear evidence that Soviet policymakers and other luminaries were fully informed of, and sometimes directly involved in, these transactions and dialogues at the highest levels.  相似文献   

3.
India and China both have powerful spy networks; completely different in their approaches to espionage; both effective against their perceived enemies. China focuses first on internal threats, on Taiwan and Hong Kong, and then the US and Japan. India’s defense policy focuses on Pakistan and internal terrorist threats, and then on China. In reality, however, when it comes to spying on each other, both China and India suffer from incompetence and apathy – which endangers both their own security and regional stability. This article looks at how they spy on each other, and asks why and how they need to improve. The narrative also touches upon some of the individuals who are waging the spy war, from India’s wily spymaster Ajit Doval down to junior Chinese agents such as Wang Qing and Pema Tsering. The two countries are not friends. They have the largest territorial dispute in the world on their hands, covering an area the size of North Korea, and they have large armies facing each other along 4000 kilometers of frontier. But they also lay claim to the world’s two oldest and richest civilizations, with a rich history of exchange, and now with a combined population of 2.6 billion people and more than a quarter of the world’s economic output. If they cooperated, they could solve many of the world’s problems; but if they lurch into conflict, the potential consequences are terrifying to contemplate. Unfortunately, despite their geographical closeness, they do not know much about each other. They have few cultural interchanges, little diplomacy, few trade missions. They do not watch each other’s films, read each other’s books or listen to each other’s music. Chinese tourists would rather fly to New Zealand for their holidays than cross the border to India, and Indian students would rather study in Europe than China. China and India are neighbors that barely talk to each other. Most significantly, they do not spy on each competently. For countries that do not interact socially, defensive understanding is important for security – but China prefers the glamor of facing up to its Pacific and other maritime rivals such as the US and Japan. India, for its part, does talk a great deal about the China threat, but its resources and expertise are wrapped up in controlling its security threat from Pakistan and the Islamic world. When China and India do try to spy on each other, it is often without the benefit of a long-term focus or understanding. India has some very skilled operatives within the Research and Analysis Wing, but few that specialize in China. China has an enormous pool of resources spread across several government departments, including the Ministry of Public Security, and also has extensive facilities and manpower in the Joint Staff Department of the Central Military Commission (the JSD) and the new Strategic Support Force (the SSF). However, China’s intelligence services generally behave as if India is not worth spying on. Given that the two countries do not have the cultural or political machinery in place to understand each other, espionage and intelligence gathering is vital to ensure that miscalculations do not take place. This has been apparent over the last few years in stand-offs in the Himalaya, as well as top-level suspicions on each side about a variety of subjects including terrorism, covert operations in Sri Lanka and Burma, and the two countries’ nuclear weapons programs. Both countries do occasionally make efforts in espionage against each other, especially during sensitive periods such as the mountain stand-offs of 2014 and 2013 and during policy developments in nuclear warfare. In this article the author looks at actual spying incidents between the two countries, their methodologies, their staff, their technical capabilities, and how the act of spying, which is usually viewed as intrinsically adversarial, can be a force for good. The article relies on interviews with actual participants in intelligence from both countries as well as extensive use of contemporary online sources, and secondary analysis by both military and academic experts from China, India and NATO countries.  相似文献   

4.

The Soviet Union was able to develop a large military-industrial complex and become the world's second superpower despite deficiencies in its centrally planned economy because defence was given high priority status and special planning, rationing and administrative mechanisms were used to attain national security objectives. However, in the period 1976-85 the effectiveness of priority protection diminished and defence institutions experienced more of the problems typical of the shortage economic system. The heavy defence burden also created growing difficulties for the civilian economy. The attempts by the Gorbachev government to reform the defence sector and improve defence-economic relationships during perestroika (1985-91) uniformly failed. For most of the transition period, the Russian military-industrial complex has been adversely affected by its low priority status, cuts in defence spending, instability of the hybrid politico-economic system, and negative growth of the economy. The armed forces and defence industry have been reduced in size and their outputs of military services and equipment have fallen to low levels. Nevertheless, the Russian armed forces still have over one million troops, significant stocks of sophisticated conventional weapons, and a large nuclear arsenal. The government of President Putin has raised the priority of the defence sector, increased real defence spending, and adopted ambitious plans to revive Russian military power. It is likely, though, that tight resource constraints will hamper efforts to reform the armed forces and to upgrade weapons. By 2010 Russia will be an important, but not dominant, military power in Eurasia.  相似文献   

5.
新疆伊斯兰教建筑装饰艺术的特征是以一种特殊的造型、形式、色彩、材质,多种多样的装饰技巧以及独有的审美特征体现出来的。是新疆伊斯兰教建筑文化体系中取得最高成就的一部分,是集实用功能、审美功能、认识教育功能于一体的艺术形式,蕴涵着地域环境、民情风俗、审美价值等丰富的内容,呈现出浓郁的风格特点。这些装饰艺术的特征,影响着人们的情绪,净化着穆斯林们的心灵,给观赏者以建筑装饰艺术的造型、色彩、纹饰的美感,获得审美的愉悦。  相似文献   

6.
NATO burden sharing has become an especially timely issue in the past several years as a result of a number of factors, including Russian annexation of Crimea and destabilization of eastern Ukraine in 2014. This article argues that alliance unity among the great democracies of Europe and North America is indispensable to peace and stability on the Eurasian continent. A fractured NATO, and especially, a large divide in purposes or commitments as between the United States and its European security partners, invites aggression and the possibility of inadvertent escalation. Past successes and failures in US-involved multinational peace and stability operations, within and outside of Europe, show that mission accomplishment requires give and take, including the occasional acceptance of unequal costs and benefits among the members, in order to achieve peace and security objectives.  相似文献   

7.
The lessons from the two French counterinsurgencies, Indochina and Algeria, give rise to a new understanding of the projection of airpower in remote and hostile environments and the purpose, design, and use of aircraft in counterinsurgency. In both Indochina and Algeria, the campaigns were ones of poverty, and it is their imaginative management under severe resource constraints that provides thoughtful and applicable lessons for today. In both cases, airpower held the promise of delivering victory and solving the resource issue. In Indochina, acquisition of the needed aircraft, operating knowledge, and experience came too slowly to realize this promise. In Algeria, the French embraced the lessons from Indochina and were quite successful and innovative in the use of airpower. The lessons can be reduced to four requirements: (1) a network of airfields for liaison, ground-support, and intra-theater airlift to enable effective air support of ground forces; (2) a solid, reliable, and simple ground-support aircraft capable of operating from forward airfields within range of ground engagements; (3) a capable intra-theater heavy-lift transport to supply the extended ground forces; and (4) helicopter capability to enhance tactical troop mobility and support.  相似文献   

8.
To alleviate flooding, caused by hurricanes, governments build structural barriers called levees. In addition, relief providers such as the nongovernmental organizations and charities raise funds, and procure and deliver supplies (food, water, and medicines) for humanitarian relief. The strategy for managing disasters must, therefore, weigh the costs and benefits of building levees as well as procuring and delivering supplies. We use a three‐stage decision making framework to study how the investment in levee capacity can be integrated with supply procurements, fundraising, and rapid response. One of our major findings is that a large fundraising cost discourages postdisaster funding, implying relatively large investments in levee and prepositioned supplies. That notwithstanding, a large social value (of saving life) can tilt the balance in favor of postdisaster funding. If the levee capacity increases, funding for predisaster procurement is reduced without affecting postdisaster funding. For a sufficiently large increase in capacity, however, postdisaster response becomes superfluous. We also find that hurricane uncertainty motivates levees with large capacity. In contrast, levee‐failures motivate levees with small capacity.  相似文献   

9.
《防务技术》2020,16(3):503-513
The paper describes field test results of 7.62 × 51 mm M61 AP (armour piercing) ammunition fired into mild steel targets at an outdoor range. The targets varied from 10 mm to 32 mm in thickness. The tests recorded penetration depth, probability of perforation (i.e., complete penetration), muzzle and impact velocities, bullet mass, and plate yield strength and hardness. The measured penetration depth exhibited a variability of approximately ±12%. The paper then compared ballistic test results with predictive models of steel penetration depth and thickness to prevent perforation. Statistical parameters were derived for muzzle and impact velocity, bullet mass, plate thickness, plate hardness, and model error. A Monte-Carlo probabilistic analysis was then developed to estimate the probability of plate perforation of 7.62 mm M61 AP ammunition for a range of impact velocities, and for mild steels, and High Hardness Armour (HHA) plates. This perforation fragility analysis considered the random variability of impact velocity, bullet mass, plate thickness, plate hardness, and model error. Such a probabilistic analysis allows for reliability-based design, where, for example, the plate thickness with 95% reliability (i.e. only 1 in 20 shots will penetrate the wall) can be estimated knowing the probabilistic distribution of perforation. Hence, it was found that the plate thickness to ensure a low 5% probability of perforation needs to be 11–15% thicker than required to have a 50/50 chance of perforation for mild steel plates. Plates would need to be 20–30% thicker if probability of perforation is reduced to zero.  相似文献   

10.
The conflict between the rebel group, the Polisario Front, and the Kingdom of Morocco is nearing its 43rd year. Though under-reported, the conflict itself garners attention for the resilience – some would say tenacity – of the ethnically Sahrawi Polisario Front. Despite shifting regional and international politics and the nearly 150,000 Sahrawi refugees waiting in nearby Algerian camps, the rebel group has survived. What explains its resilience? This article uses Bourdieu’s ‘forms of capital’ to understand the Polisario Front’s persistence. Based on field research in Algeria, Western Sahara, and the United States, it finds that social, cultural, symbolic, and economic capital may provide an explanation.  相似文献   

11.
低慢小无人机具有小型化、红外与雷达暴露征候小、飞行高度低、飞行轨迹不定以及购买使用几乎无门槛等特征,给当前全球军事区域和军事行动安全带来了新的挑战。本文首先分析了世界主要国家对低慢小无人机的界定、国内外管控情况和相关威胁事件;然后,从低慢小无人机的侦察袭击能力、军事区域现有安防措施和低慢小无人机对军事区域进行侦察的相关案例入手,讨论了低慢小无人机对军事区域的侦察袭击的威胁;最后从政策制度、营区部署与隐蔽伪装以及反制措施配置三方面对军事区域防低慢小无人机侦察袭击的手段与措施进行了分析和研究,重点就机动性、经济性、技术难度、可操作性、反应速度、打击效果、能否对抗集群目标以及适用场合等方面对当前各种反无人机的干扰、驱离、毁坏措施进行了对比。  相似文献   

12.
根据无人车用智能导航技术相关的研究与综述论文、专利发表情况,对该专业技术领域进行总体分析。选取1990—2020年的数据,针对论文发表情况,主要对其发展趋势、国家/地区分布、机构分布、出版物分布、高被引论文、被引频次和研究主题进行深入分析;针对专利申请现状,主要对专利申请时间、国家/地区分布、专利权人、专利研发技术热点等进行深入分析。研究结果表明,在无人车用智能导航技术研究领域,美国和中国无论在论文还是专利的数量和质量方面,均处于世界前列。该技术领域的研究热点主要集中在导航系统、导航卫星、惯性技术、地球物理数据、自主车辆导航、自主车辆定位、激光雷达、位置数据、神经网络、目标跟踪算法、传感器、卷积神经网络、自动驾驶等方面。  相似文献   

13.
《防务技术》2020,16(3):668-677
The formation and separation behaviors of tandem EFPs are studied by the combination of experiments and simulations. The results show that different formation and separation processes can be obtained by adjusting the double-layer liners, and simulations agree with experiments well. Then, the interaction process between the two liners is discussed in details, and the formation and separation mechanism are revealed. It can be found that there are four phases in the formation and separation processes, including impact phase, propulsion phase, slide phase and free flight phase. During the impact phase, the velocities of two liners rise in turns with kinetic energy exchange. In the propulsion phase, the axial impact becomes insignificant, but the radial interaction between two liners influences the appearance of tandem EFPs. Meanwhile, it should be mentioned that the inner surface of foregoing EFP remains to be in contact with the outer surface of following EFP in the propulsion phase, and the following one would continue to push the foregoing one for about 10μ to 20 μs, causing the velocities of following and foregoing EFPs gradually decreasing and increasing respectively. In the slide phase, an obvious relative movement occurs between the two EFPs, and there would be barely kinetic energy exchange. Then, the two EFPs separate gradually and get into the phase of free flight. Generally, if the outer and inner liners have the same thickness, the outer copper-inner copper liners form two long EFPs, the outer copper-inner steel liners become a foregoing short steel EFP and a following long copper EFP, and the outer steel-inner copper liners produce a foregoing long copper EFP and a following conical steel EFP. In addition, thickness match also has an important impact on formation appearance and separation process for both outer copper-inner copper liners and outer steel-inner copper liners. With the thickness ratio of outer liner to inner liner decreasing, the length and length-diameter ratio of both foregoing and following EFPs increase gradually.  相似文献   

14.
Machine learning algorithms that incorporate misclassification costs have recently received considerable attention. In this paper, we use the principles of evolution to develop and test an evolutionary/genetic algorithm (GA)‐based neural approach that incorporates asymmetric Type I and Type II error costs. Using simulated, real‐world medical and financial data sets, we compare the results of the proposed approach with other statistical, mathematical, and machine learning approaches, which include statistical linear discriminant analysis, back‐propagation artificial neural network, integrated cost preference‐based linear mathematical programming‐based minimize squared deviations, linear integrated cost preference‐based GA, decision trees (C 5.0, and CART), and inexpensive classification with expensive tests algorithm. Our results indicate that the proposed approach incorporating asymmetric error costs results in equal or lower holdout sample misclassification cost when compared with the other statistical, mathematical, and machine learning misclassification cost‐minimizing approaches. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006.  相似文献   

15.
随着管道机器人应用领域与任务需求的不断增大,机器人设计中存在的问题日益突出,如输出功能相互耦合、定位精度不高以及复杂环境下可靠性低。针对石油水平井对于管道机器人的特殊应用需求,将公理化设计理论应用到机器人系统设计中,创新设计一种基于挠性支撑结构的全液压驱动管道机器人。概述公理化基本原理与设计过程,对全液压驱动管道机器人进行概念设计,完成设计耦合性分析。确定机器人机械系统与液压系统具体结构组成,并分析其工作机理。应用AMESim软件,对机器人运动原理方案进行仿真分析,结果表明:全液压驱动管道机器人可以实现自动往复运动,牵引力可以达到30 kN,运动速度可以达到0.12 m/s;机器人牵引能力与运动速度可以完成单独调节,从而实现解耦设计。  相似文献   

16.
毛国辉 《国防科技》2014,35(6):54-58
制约太空军备竞赛、防止太空武器化已成为维护太空安全、维持全球战略稳定的一个重要方面。构建与完善包括空间物体登记制度、透明与信任建设机制及核查制度在内的太空安全监管制度,对于消除、缓解国家间误解与紧张关系,促进世界主要国家的信任与合作,维护各国太空活动安全,具有积极作用,不失为一条务实、有效的共同抵制太空武器化的重要路径。  相似文献   

17.
张伟年  蔡辉  范冰冰 《国防科技》2021,42(3):127-134
为了推进维和军事训练的创新发展,军队必须大力进行维和训练理念、模式、方法和手段的改革,有效提升维和官兵的实战能力。本文依据多模态理论、自主学习理论和建构主义学习理论的研究成果,根据网络环境实际提出构建以培训学习者岗位任职综合技能为目的、以强军网络学习环境为依托的基于浏览器/服务器(B/S)架构模式的军事维和多模态网络自主学习平台。该平台能够让学生自主选择学习内容、查看学习进度和效果反馈、访问优质数字资源、利用虚拟社区与教师和同学共同讨论学习内容、学习心得,并且通过智能化的推荐来合理制定适合自身认知结构的学习计划和方式。平台的建立为构建以学习能力、实践能力、创新能力培养为导向,与新型军事人才培养相适应的教学体系和教学模式提供了有益的探索。  相似文献   

18.
作家董立勃把炽热的笔触深深地扎在西部边地“下野地”,以其特有的视角叙述了上海姑娘宋兰从遭受强奸、被逼下嫁到最终成为支边典型和江南少女米香从执着追求真爱、迷失自我、放纵报复到最终不知去向的不同的生命故事。董立勃用诗化的语言与激情畅快淋漓地向人们展示了生活在“下野地”的年轻女性善良纯情、大胆真诚、敢爱敢恨的生命韧度,从她们对爱与恨、善良与罪恶、希望与反抗、真诚与背叛的苦难抉择中彰显了作家对生命、对人生、对时代的理性思考。从女性复仇的意义上来说,《米香》是恨的悲歌,也是爱的哀曲。  相似文献   

19.
在构建首都大周边维稳预警机制中,情报工作具有监测、预测和辅助决策功能。社情监测离不开情报的收集,维稳社情预测依赖于情报的分析、研判、传递与通报,危害社会安全稳定案件预控离不开情报支撑。做好首都周边地区维稳预警工作,需要健全和完善情报收集制度、情报分析和研判制度、情报送报制度、相关情报工作制度以及社会舆情信息汇集与分析制度。  相似文献   

20.
Despite both regional and international efforts to establish a weapons of mass destruction–free zone (WMDFZ) in the Middle East, regional support beyond mere rhetoric seems unattainable. The lack of commitment to WMD disarmament results from the complexity of regional security dynamics, which are characterized by a high level of weaponization and crosscutting conflicts. This article examines a strategy for WMD disarmament in the Middle East. First, such a strategy must reflect the motives underlying a state's WMD aspirations. Security and prestige may be identified as two motives that affect the acquisition, and thus also the abandonment, of WMD. Second, Egypt, Iran, Israel, and Syria are important actors because their reasons for desiring WMD cannot be considered apart from each other, and progress will consequently depend on the inclusion of all these actors. In this regard, we recommend the establishment of a parallel process between efforts to establish a WMDFZ and peaceful relations in the Middle East. Solving central problems, like the lack of political determination and security cooperation, is vital to create consensus on the final framework of a zone. This study suggests a way forward by analyzing the central causes of conflict in the region and recommending ways to resolve them in order to establish a WMDFZ.  相似文献   

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