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971.
Classical geopolitics,realism and the balance of power theory   总被引:1,自引:0,他引:1  
Since the end of World War II, classical geopolitics as a particular form of realism has been disengaged from the development of mainstream realist theories. This disengagement has not only concealed the value of classical geopolitics as a framework of analysis for policy and strategy, but also created an increasing rift between theory and policy in contemporary realist theories. This paper seeks to reengage classical geopolitics with mainstream realist theories by clarifying its realist traits and analytical characteristics, (re)stating its core propositions and probing into its potential contribution to the development of mainstream realist theories. This paper contends that classical geopolitics, while having a distinctive pedigree, can arguably be considered an integral part of the family of realist theories in view of its basic theoretical assumptions concerning international anarchy, the unit of analysis and power politics. As a framework of analysis, classical geopolitics incorporates three interrelated strategic propositions. Those three propositions not only constitute the theoretical core of classical geopolitics, but also manifest a peculiar balance-of-power conception that is essentially distinct from those proposed by mainstream realist theories. This paper argues that those three propositions combined promise to fill in prominent lacuna in the balance-of-power research programme, and also have significant implications for contemporary world politics.  相似文献   
972.
This article argues that the nuclear nonproliferation norm (NNPN) is a social fact with a relatively independent life of its own and that it has a powerful impact on the behavior of both nuclear-weapon states (NWS) and non-nuclear-weapon states (NNWS). It challenges the application of critical constructivist research on norms to the NNPN and the idea that its legitimacy and structural power depend on contestation “all the way down.” State and non-state actors play an important role in explaining the dynamics of the NNPN, but agential constructivism runs the danger of “throwing the baby out with the bath water,” neglecting the structural impact of the NNPN on state behavior. The article examines the limitations of norm-contestation theory, arguing that some norms are more resistant to contestation than others. The NNPN is more difficult to contest than new norms (such as the Responsibility to Protect) because it is rooted in fifty years of nonproliferation nuclear diplomacy. The US-India nuclear deal is not a case of “norm change” but a violation of the NNPN. The “core” of the NNPN has not changed since the US-India nuclear deal. The conflict confronting NWS and NNWS is about the implementation of “type 2” norms (organizing principles) and “type 3” norms (standardized procedures), and not about the “hard core” of the NNPN.  相似文献   
973.
This article explores why the offensive predominates military tactical thinking. With survey results showing an offensive bias among 60 per cent of senior Swedish officers and as many as 80 per cent in the case of the army, it is clear that this is not just a problem of the past but is equally relevant today. The article asks why there is a tendency to perceive and understand offensive tactics as the preferred choice and the way to conduct battle that should be encouraged and preferred. Drawing on existing research and the findings of a pilot study, ten propositions for why the offensive bias exists are tested using a mixed-method approach. Based on the findings, the article develops a model to understand why the offensive dominates military tactical thinking. It is found that the two key constitutive factors behind the offensive bias are military culture and education. These factors most directly and profoundly influence an officer’s identity, perceptions, and thinking. Military culture and education, in turn, work as a prism for four other factors: military history, the theory and principles of war, doctrine and TTPs, and psychological factors.  相似文献   
974.
针对电磁发射弹丸飞行弹道进行仿真研究,在建立刚体六自由度飞行弹道模型的基础上,采用时频分析和涡流分析方法,建立电磁-动力学耦合模型分析弹丸出膛时由于膛内振动带来的炮口扰动,采用动网格技术建立电磁-气动耦合模型分析弹托分离产生的气动扰动,从而得到了电磁发射弹丸的飞行弹道模型。以得克萨斯大学先进技术研究所设计的IAT-HVP为例,仿真分析了弹丸以1117 m/s初速、0°射角出膛时弹丸出口扰动对弹体速度和气动特性的影响,并得到其飞行200 m的弹道曲线。仿真结果表明,受电磁发射一体化弹丸出口扰动的影响,弹体落点相比理想弹道产生了24%的偏差,其中炮口扰动引起的偏差最大,其次是弹托分离。  相似文献   
975.
发展显微成像方法获得空间分辨率为1.57 μm/pixel的近场射流瞬态图像,分析超声速气流中液体横向射流表面波演化规律。采用流体体积法获得射流的三维形态及近场流场特征,研究近场流场结构及气液作用。射流的一次破碎过程主要有表面破碎和液柱破碎。其中表面破碎由气液剪切引起的K-H不稳定主导,液柱破碎由气液加速引起的R-T不稳定主导;射流柱表面局部压力的脉动是诱导产生射流迎风面表面波并促使其沿射流方向发展的主要原因;射流柱与超声速气流作用形成背风面回流,近壁面液雾主要由表面破碎及背风面回流输运的液滴组成。  相似文献   
976.
无扰载荷航天器中非接触式作动器反电动势会引起有效载荷模块与支持模块之间的耦合,影响有效载荷模块的精确定向性能。通过建立无扰载荷航天器的耦合动力学模型,分析非接触式作动器反电动势对有效载荷模块精确定向性能的影响。考虑六支杆立方构型无扰载荷接口,结合拉格朗日方程和牛顿欧拉方法建立有效载荷模块平台动力学模型。推导非接触式作动器的输出力模型,并引入有效载荷模块平台动力学模型,给出考虑非接触式作动器反电动势的耦合动力学模型。将支持模块上飞轮动静不平衡引起的谐振作为干扰力矩,建立了无扰载荷航天器在轨定向状态的Simulink仿真模型。仿真结果表明,反电动势系数越大,干扰力矩对有效载荷模块的影响越大,有效载荷模块精确定向精度越低。  相似文献   
977.
提出了非致命防暴动能弹作战效能的评估法,分析了非致命防暴动能弹的技术性能,建立了以非致命性为核心指标的防暴动能弹效能指标体系。采用定性分析与定量分析相结合,将集对分析法应用到了非致命防暴动能弹的效能评估中,对3种防暴动能弹进行了效能评估。为非致命防暴动能弹的研发生产提供了重要的理论支撑。  相似文献   
978.
本文证明了二部图存在(g,f)匹配和f 因子的充要条件以及有关的几个结果,并且给出了求二部图的最大(g,f)匹配、最小(g,f)匹配和最小权最大f 匹配、最小权(g,f)匹配、最大权(g,f)匹配的算法。  相似文献   
979.
在行星轮系机构综合中,研究行星轮数目与极限传动比的关系有着极其重要的意义。本文根据2K─H行星轮系机构的同心条件、安装条件和邻接条件,采用统一的符号,对满足上述条件的所有(六种)2K─H行星轮系机构,导出了行星轮个数与极限传动比的统一关系式,得到了所有2K─H行星轮系机构的极限传动比计算公式,为2K─H行星轮系机构的综合提供了理论根据。  相似文献   
980.
经典的侦察与监测(S&R)系统效能分析方法存在模型难以建立、结果不准确等问题。考虑到S&R系统的目的是提供情报支持,提出一种基于信息需求的S&R系统情报支持效能分析方法。该方法以用户的信息需求为度量基准量,比较S&R系统性能对信息需求的满足度,并以此满足度作为S&R系统效能度量的指标。仿真实例表明了新方法的有用性。  相似文献   
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