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1.
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   

2.
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   

3.
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   

4.
Book reviews     
Export or Die: Britain's Defence Trade with Iran and Iraq. by Davina Miller, London: Cassell, 1996, ISBN 0-304-33852-4 (hbk), £40.00, 04-33853-2 (pbk), £11.99.

The Storm Passed By: Ireland and the Battle of the Atlantic, 1940-1941. by Trevor Allen, Dublin: Irish Academic Press, 1996, ISBN 0-7165-2616-6, (hbk) £17.50.

Arms Control Toward the 21st Century. by Jeffrey A. Larsen and Greqory J. Rattray (eds). Boulder: Lynne Rienner, 1996.

Asia-Pacific Security, Less Uncertainty, New Opportunities. Edited by Gary Klintworth. Melbourne: Addison Wesley Longman, 1996, ISBN 0-582-80321-7, £24.99.

Masters of War, Military Dissent and Politics in the Vietnam Era. by Robert Buzzanco, Cambridge: Cambridge University Press, 1996, ISBN 0-521-48046-9 (hbk), £29.95

Controlling the Arms Trade: the West Versus the Rest. By Paul Cornish, London: Bowerdean Publishing Co., 1996, ISBN 0-906097-44-4 (pbk), £9.99.

Secret Agencies: US Intelligence in a Hostile World. by Loch K. Johnson, London: Yale University Press, 1997, ISBN 0-300-06611-2 (hbk), £22.50.  相似文献   

5.
本文分析了冲压式翼伞开伞的特点,提出了一个展弦向二维开伞模型,建立了伞衣的径向运动方程。在推导系统运动方程和分离体运动方程的基础上,建立翼伞开伞仿真状态方程,用龙格-库塔法求解,给出开伞充满时间、开伞动载、翼伞速度和位置坐标等参数的变化值。本文提供的开伞仿真计算软件包,可用于各类冲压式翼伞的开伞仿真计算。  相似文献   

6.
动物机器人由于具有出色的隐蔽性和环境适应性,可能在未来战争或局部冲突中会扮演重要角色,成为决定战场胜负的杀手锏。针对动物机器人及其潜在的军事应用价值,本文介绍了动物机器人的原理,根据动物生存环境的差异综述了陆地动物机器人、飞行动物机器人和水下动物机器人等三种类型机器人的研究现状;在此基础上,分析了动物机器人在抵近侦察、目标引导、对象识别和直接打击等方面的潜在军事应用价值,并讨论了动物机器人走向实用过程中存在的刺激靶点、刺激方式、生物相容性、操控器件、无线通讯以及能源供给等方面存在的工程问题以及未来研究方向。动物机器人优势十分明显,但对技术的要求也非常高,目前仅仅处于起步阶段,未来的路还任重道远。  相似文献   

7.
Book reviews     
Encyclopaedia of Modern Air Force Squadrons. By Chris Ashworth. Patrick Stephens, London (1989), ISBN 1-8526-013-6, £19.95

The Future of Sea Power. By Eric Grove. Routledge, London (1990), ISBN 0-415-00482-9, £35.00

Soviet Strategic Interests in the North. By Kirsten Amundsen. Pinter, London (1990), ISBN 0-86187-018-2, £30.00

Soviet Seapower in Northern Waters. Edited by John Skogan and Arne Brundtland. Pinter, London (1990), ISBN 0-86187-038-7, £35.00

Glasnost, Perestroika, and U.S. Defense Spending. By William W. Kaufmann, Brookings Institution, Washington, DC (1990), ISBN 0-8157-4881-7, $8.95

The Educating of Armies. Edited by Michael D. Stephens. Macmillan, London (1989), ISBN 0-333-43447-1, £35.00  相似文献   

8.
Electromagnetic railgun attracts more and more attention due to its advantage in speed,cost,and obscurity.It is found that the rail should withstand huge mechanical and thermal shocks during the launching operation.The forms of rail failure are accompanied by gouge,grooving,transition,and arc ablation,etc.The service life of the rail has become a bottleneck restricting the development of elec-tromagnetic railgun technology.A series of researches are carried out to solve rail failure,including analysing the failure mechanism and using various advanced rail materials.This paper provides a comprehensive review of rail materials,including material composition,preparation,microstructure,and properties.We begin from a short background of the requirement of the rail material.Then a detailed investigation of rail materials is described,and the performances of those materials are introduced.Finally,further development prospect of rail material is discussed.  相似文献   

9.
装备竞争性采购是统筹经济发展和国防建设的重要抓手,加强风险管理是提升装备竞争性采购总体效益的重要保障。从当前纪检态势看,装备竞争性采购是廉政风险集中的重点领域。本文系统梳理了思想道德、制度机制、岗位职责及社会环境等装备竞争性采购过程中可能遇到的廉政风险类型,阐述了竞争性采购项目提出环节、竞争性采购信息发布环节、候选装备承制单位确定环节、竞争性采购实施环节以及合同订立履行阶段等的风险点及其产生原因,针对性地提出了严格计划编报环节管理、扩大采购信息发布范围、规范竞争性采购过程管理以及健全完善评估监督机制等风险防范措施。最后,展望了综合集成专家经验、案例数据和模型算法的定性定量结合分析方法在装备竞争性采购风险分析研究中的应用前景。  相似文献   

10.
空间绳网系统展开动力学特性分析   总被引:1,自引:0,他引:1       下载免费PDF全文
空间绳网系统是一种新型轻质空间柔性结构,具有很大的应用价值。针对地面环境和太空环境下的不同受力特性,推导空间绳网动力学模型;通过地面试验验证仿真模型的可信度;基于展开面积、飞行距离等性能参数,仿真分析空间绳网展开过程中的绳网位形、应力分布以及能量变化等动力学特性,分析轨道高度、捕获方向和发射参数对展开效果的影响。  相似文献   

11.
战略决策模拟中,态势表现是实现模拟可视化的关键,具有举足轻重的作用,其研究与实现是一项具有相当难度的课题.首先分析战略态势表现所要解决的两个基本问题,即态势数据和可视化表现;其次着眼于两者的分离,按照面向对象的设计思想,提出了一种面向对象的战略态势表现实现思路;最后,给出了开发战略态势表现系统的基本工作思路.在决胜系列战略决策模拟系统的开发中,按照该思路实现了态势表现子系统,较好的满足了模拟需求.  相似文献   

12.
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   

13.
采用盆栽试验法,研究了黑麦草、苏丹草、油菜对土壤中菲、芘的去除效果,及植物和微生物去除土壤中菲、芘的交互效应。结果显示:菲、芘质量比约为80 mg.kg-1时,土壤-植物系统对菲、芘的去除效果明显。种植黑麦草、苏丹草、油菜60 d后,土壤菲、芘降解率分别为62.70%,76.25%,26.48%和47.80%,65.26%,23.56%,分别比无植物对照高39.69%,53.24%,3.47%和30.06%,47.48%,5.78%。本实验说明,植物可以促进微生物对土壤中菲、芘的降解,其中根系发达的苏丹草对微生物降解的促进作用最为显著。  相似文献   

14.
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   

15.
BTT导弹制导律研究综述   总被引:1,自引:1,他引:0       下载免费PDF全文
与STT导弹相比,BTT导弹在气动效率、机动能力、控制性能等方面具有明显优势,但其运动耦合特性也给传统研究框架下的制导律设计带来了挑战。本文针对BTT导弹制导律设计问题展开研究,首先描述了BTT导弹制导基本问题,分析了BTT导弹制导律设计的技术难点,需要综合考虑运动耦合、多约束、目标机动、弹体动态效应等因素,然后综述了国内外现代制导律设计的基本方法,将其分为双通道解耦法、球坐标法、现代几何法等,最后指出了BTT导弹制导律的进一步研究方向。  相似文献   

16.
Book reviews     
Norman Cigar, Genocide in Bosnia: The Policy of “Ethnic Cleansing”. College Station, Texas: Texas A&M University Press, 1995. Pp.xiv + 247; app., map, notes, cartoon.

Maria Jose Moyano, Argentina's Lost Patrol: Armed Struggle, 1969–1979. New Haven: Connecticut Yale University Press, 1995. Pp.xiii + 226, biblio., abbreviations, 10 figures, 1 map, tables, index; $25/£16.95. ISBN 0–300–01622–6.

Donald E. Schulz and Deborah Sundloff Schulz, The United States, Honduras, and the Crisis in Central America, Westview Thematic Studies in Latin America, Boulder, Co: Westview, 1994. Pp.368, map, figure, select biblio., abbreviations, index. $52.50/£37.50; (cloth) $17.95/£11.95 (paper). ISBN 0–8133–1324–4 and 1323–6.

Joseph H. Alexander and Merrill L. Bartlett, Sea Soldiers in the Cold War: Amphibious Warfare 1945–1991. Annapolis, Maryland: Naval Institute Press, 1995. Pp.iii + 178, 1 map, 29 illus, biblio, index. $32.95. ISBN

Gary P. Cox, The Halt in the Mud: French Strategic Planning from Waterloo to Sedan. Westview Press, 1994. Pp.258, maps, notes, biblio, index. £33.50. ISBN 0–133–1536–0.  相似文献   

17.
Hub terminals are important entities in modern distribution networks and exist for any transportation device, that is, cross docks and parcel distribution centers for trucks, container ports for ships, railway yards for trains, and hub airports for aircraft. In any of these hubs, the mid‐term planning task of synchronizing the transshipment of goods and passengers when servicing the transportation devices has to be solved, for which many different solution approaches specifically tailored to the respective application exist. We, however, take a unified view on synchronization in hubs and aim at a general building block. As a point of origin, a basic vertex ordering problem, the circular arrangement problem (CAP), is identified. We explain the relation between the CAP and hub processes, develop suited algorithms for solving the CAP, and extend the basic CAP by multiple additions, for example, arrival times, limited storage space, and multiple service points, make the problem adaptable to a wide range of hub terminals. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 454–469, 2015  相似文献   

18.
影响武器装备维修质量的基本要素分析   总被引:4,自引:0,他引:4  
制约、影响维修质量的因素是多方面的.从武器装备系统的全寿命过程出发,将影响维修质量的基本要素概括为7个方面即维修人员素质、维修设备与设施的状况、装配工艺、维修生产环境、原材料、备品备件的质量、维修管理制度等.通过具体研究、分析影响维修质量的这些因素及其特征量,指明这是实现维修质量管理和评定目标的必经之路,只有影响因素明确了,才能有的放矢地对维修质量进行管理、控制与评定.  相似文献   

19.
管道热边界层方程的迎风有限元分析   总被引:2,自引:2,他引:0  
对于管道热边界层方程,除了采用动量积分方法求得理论解析解外,也可以用数值方法求解,如有限差分、有限体积、有限元等方法.理论解析解是采用一定的简化并忽略若干项之后得到的,因此,也只是一种近似解,数值解可以考虑完整的方程和各种边界条件,因而其解较为全面.采用伽辽金有限元方法求解,管道热边界层方程为标准的对流扩散方程,当对流项较强时,需要采用迎风方法,因而也给出了迎风有限元方法的模型.  相似文献   

20.
舰艇保障是一种主要依赖后勤技术装备的专业化后勤,也是涉及并行、冲突,并受资源、装配时间等限制的复杂离散事件过程。借助定时Petri网强大的描述能力标记过程中的各种动态行为,在此基础上对包括后勤装备在内的后勤实体、保障任务、保障活动等进行建模,采用编码、转换等手段实现舰艇保障过程仿真,并使用仿真结果对后勤保障能力进行"定量计算"为主的分析评估。  相似文献   

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