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1.
本文利用NSA理论和方法研究系统X(t)=f(t) integral from n=o to t g(t,s,x(s))ds(1)和x(t)=f(t) integral from n=∞to t g(t,s,x(s)ds(2)解的有关问题.得到有关VOltterra积分方程的基本结果类似于常微分方程中的相应结果,在解决问题的技巧上是独特的.特别是用NSA方法对(2)式的处理比经典理论大为直观和简洁.  相似文献   

2.
设X为实一致光滑Banach空间 ,A :X→X为Lipschitz强增生算子 ,设L≥ 1和k∈( 0 ,1)分别为A的Lipschitz常数与强增生常数。设 {tn}n≥ 0 为 ( 0 ,1]中的实数列满足条件 :(i)tn→ 0 (n→∞ ) ;(ii)∑∞n =0 tn=∞ , f∈X , x0 ∈X ,迭代地定义序列 {xn}n≥ 0如下 :( )  xn 1 =xn-tn(Axn- f) ,n≥ 0 .则 {xn}n≥ 0 强收敛于方程Ax =f的唯一解 ,而且对充分大的n≥n0 ,‖Axn- f‖ ≤ exp{-k∑n- 1j=n0tj}‖Axn0 - f‖  一个相关的结果研究含强伪压缩映象的方程Tx =x的构造可解性。  相似文献   

3.
假定(X1,Y1),(X2,Y2),…,(Xn,Yn)是取自二维随机向量(X,Y)的独立同分布样本.记X(1)≤X(2)≤…≤X(n)是X1,X2,…,Xn产生的次序统计量,Y[1],Y[2],…,Y[n]是诱导的次序统计量.讨论广义L-统计量Tn=n-1 n∑i=1 J(i/n+1)Y[i]的极限分布,式中J(x)是由实际问题的需要而选取的权函数.在较弱的条件下,证明了Tn的渐近正态性,同时给出了Tn的期望和方差的渐近公式.  相似文献   

4.
研究了形如X'(t)∈-Ax(t)+F(t,x(t)),0≤t≤T,X(0)=x0的微分包含解的存在的局部性和整体性的结果,并在某种条件下研究了解的稳定性。  相似文献   

5.
设X为一致凸的Banach空间,T:X(?)D(T)→X为m—增生的且强增生的算子,T_0:X→X为线性紧算子。C:X→X为全连续算子,应用Leray-Schauder度理论,研究了算子方程Tx-T_0x Cx=f,f∈X的可解性。  相似文献   

6.
基于X射线脉冲星的Halo轨道卫星自主导航和控轨   总被引:1,自引:0,他引:1  
讨论x射线脉冲星自主导航(X—raypulsar-basedautonomousnavigation,XNAV)技术应用于halo轨道卫星的可行性。给出halo轨道卫星的6维状态方程和基于x射线脉冲星导航的6维观测方程,对用x射线脉冲星导航和小推力方法控轨后的日地系第一平动点halo轨道卫星进行了数值模拟。结果表明:在现有的测量精度下,可以将卫星保持在标准轨道附近。最后对实验参数数值的选择给出了相应的分析讨论。  相似文献   

7.
数形结合就是把抽象的数学语言与直观的陪衬图形有机地结合起来进行思考,促使抽象思维与形象思维和谐渗透,通过对规范图形或示意图的观察分析,化抽象为直观,化直观为精确,从而使问题得到简捷地解决。函数图像法是用图像来表示两个变量的函数关系,其优点是形象直观。函数的图像是学好函数知识直观形象的工具,通过观察函数图像的变化趋势,可以总结出函数的性质。另外函数图像是数形结合的有效载体,它以形为主,辅之以数,用于一类恒成立不等式的求解上,可谓另辟蹊径,别开生面,而使问题的解决别具一格。例1:设关于x的不等式(x-1)2相似文献   

8.
预备知识定义设函数g(x)任C“,张算子29:C-一C‘,定义为 Z。(‘’‘·,一(毙)‘这样,““,(·,一(病(毙{,其余类推。关于张算子有如下三个结论:命题一若f(x)任C一,且f(x)=ah(x)(a为常数),则有Z盆(f)(x)=aZ菩(h)(x)(Vn任N)。命题2设f(x)、g(x)任C一,且f(o)=g(0)~o,f‘(0)=g‘(0)一1,那么,(1)Z‘(f)(o)=一Zf(g)(0);(2)若Z尝(f)(o)~o,1簇k成n一z,则Z盆(f)(o)-一ZP(g)(o)。命题3 Li色nard型方程!爷一y一万(于’几y-一g叹Xj其中;(二)一芡f(?)d?,f(。)一。,g(X)一 h一t,并设v3,vs,一vZn·;表示各阶焦J点量。,;么,(1)v3一z:(,)(。)一}澳{…  相似文献   

9.
波动方程(见参考文献4)求一个给定源的亘和百的关系,出发点是麦克斯韦方程。麦氏方程是(BI)甲X亘(f,t)=一口百(f,t) 口t(BZ)甲x百(f,t)=拼,J(f,t) 拼,£,d豆(f,t) 口t(B3)二.亘(f,。)=事。。(f,t), 肠v(B4)甲·豆(f,t)=0-式中变量是第111章中标出的。从现在起,要假定电流源周围媒介导电率是零。(B4)总是真的,因此可以说(BS)百=甲xA,式中A现在还是一个任意向量。将(BS)代入(Bl),并假定A具有旋度算子与时间导数算子可以交换的性质,就得出 0︶ 一一、.、‘J(B6)二X{:‘,,t, 口A(f,t) Jt对任何数量V,甲x甲V=0总是真的,因而不失去一般…  相似文献   

10.
讨论下列中立型含逐段常滞量微分方程的伪概周期解d2dt2(x(t)+p(t)x(t-1))=qx(2[t+12])+g(t,x(t),x[t])采用不动点定理和构造伪概周期序列的方法,得到了此方程的伪概周期解的存在性,并推广了文献[5~8]中的有关结果。  相似文献   

11.
Recent events demonstrate the complex and adaptive approach employed by Russia to reassert influence in Europe. The changing face of Russia’s strategy commenced in 2007 when it launched a crippling cyber-attack against Estonia. This was followed by a large Russian conventional attack against Georgia in 2008, occupying two large areas of the nation. 2014 witnessed the Russian annexation of Crimea where in just a week, Russia seized control of Crimea “without firing a shot.” The annexation of Crimea was rapidly followed by a Russian inspired and led subversive war in eastern Ukraine. The common thread among these diverse Russian operations is its use of ambiguity to confound and confuse decision makers in the West.  相似文献   

12.
The Indian Army, a force trained primarily for conventional warfare, has been engaged in internal counter-insurgency operations since the 1950s. Despite such a long innings on a counter-insurgency mode, little attention has been accorded within military circles to doctrinal innovation for waging sub-conventional warfare in India's democratic political context. At best, the Army continues to view counter-insurgency duty as secondary to its primary duty of defending India from external conventional threats. By conceptualizing a counter-insurgency strategy of ‘trust and nurture’, this article aims to fill this critical doctrinal gap in India's military policy. The author argues that a counter-insurgency strategy of ‘trust and nurture’ based on democratic political culture, measured military methods, special counter-insurgency forces, local social and cultural awareness and an integrative nation-building approach will result in positive handling of India's internal security problems. The author utilizes India's counter-insurgency experiences in Assam, Mizoram, Nagaland, Punjab, and Operation ‘Sadhbhavana’ in Jammu and Kashmir as illustrative empirical indicants in order to validate the ‘trust and nurture’ strategy.  相似文献   

13.
In the Post-Bipolar Era the growing complexity of the military operations requires a new approach for the resolution of international crises. Since the end of the Cold War, peace support operations (PSO) have become the mainstay and principal occupation of most Western armies. At the same time, Italy has been one of the most important actors in such an area. The article focuses on the cooperation between military and civil components (a process called CIMIC) as a key variable in the Italian PSOs. We will analyse in detail the main lessons learned from past military interventions as well as the general context in which new tendencies are taking place. The maintaining of a minimum security frame becomes essential to fulfil activities ‘collateral’ to the mission: reconstructing services and infrastructure, food distribution, water and medication, law and order, de-mining, training of local forces, and supporting local institutions. These are the main tasks to obtain thrust and support from the population.  相似文献   

14.
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   

15.
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   

16.
The September 11 global crisis prompted by the attacks on the World Trade Center and the Pentagon raises major questions concerning the nature and trajectory of terrorism in the post-Cold War global order. Hitherto, terrorism has been largely debated by analysts at the level of nation states. Terrorist and insurgent movements have also been largely anchored in nationalist and ethnic power bases even when they have sought to mobilise a transnational ideological appeal on religious or class grounds. There have been a few exceptions to this pattern such as the alliance between the German Baader-Meinhof group and the Japanese Red Army Faction, but even such international alliances as this did not, until at least the 1980s, presage anything like a global terrorist network necessitating a global strategic response. This study examines terrorism and global strategic responses.  相似文献   

17.
This article analyses to what extent the Burmese KNU insurgency made use of external support from states, refugees, and diasporas. Based on extensive fieldwork it is concluded that support from neighbouring states and refugees has for years kept the Karen rebellion alive. Western countries perceived forms of resistance to the illegitimate Burmese regime as just and have therefore played a crucial role in the continuation of conflict in Karen State. It is important that policymakers and donors as well as executing organizations continue to reflect critically on the way they exercise their work.  相似文献   

18.
19.
Reviews     
Douglas S. Derrer, We Are All the Target: A Handbook of Terrorism Avoidance and Hostage Survival. Annapolis, MD: US Naval Institute Press, 1992. Pp. x+135, notes, index. $14.95. ISBN 01–55750–150–5

Ian Knight, Zulu: Isandlwana and Rorke's Drift, 22–23 January 1879. London: Windrow & Greene, 1992. Pp.136, 150 illus., incl 8 colour plates, maps, biblio. £35. ISBN 1–872004–23–7

Ian Knight, By the Orders of the Great White Queen: Campaigning in Zululand through the Eyes of the British Soldiers, 1879. London: Greenhill Books and Novato: Presidio Press, 1992. Pp. 272, 17 illus., 1 map. £18.95. ISBN 1–85367–122–3

Manfried Rauchensteiner and Erwin A. Schmidl (eds.), Formen des Krieges: vom Mittelalter zum ‘Low‐intensity’ Conflict’. Graz : Verlag Styria, 1991. Pp.208. DM35. ISBN 3–22–12139–7

Harold J. Kearsley, Maritime Power and the Twenty‐First Century. Dartmouth: Dartmouth Publishing Company, Limited, 1992. Pp.xv + 203, 13 diagrams, index. £32.50. ISBN 1–85521–288–9  相似文献   

20.
装备的RMS是装备的重要设计参数,是影响战备完好和保障能力的关键因素.引入GTST-DMLD作为主要建模工具,建立起装备系统的RMS描述模型,以ESD为补充和扩展,对维修过程进行建模.并以GTST-DMLD-ESD模型作为装备RMS仿真的核心,对装备RMS仿真模型的总体框架进行了研究,并对各模块进行了较为详细的探讨.  相似文献   

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