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This article advances the existing literature on British imperial aeronautics by explaining how Lord John Montagu’s extensive collaboration with military and government officials during the first decades of powered flight expanded the global distribution of the air forces and anticipated their important later role in facilitating international communication and security. In reconsidering problems of conquest and governance through an aeronautical perspective, Montagu strengthened critical junctures between British civil and military affairs, while his innovative employment of the new technology also complicated divisions between the metropolis and periphery in ways that would intensify the destructiveness of modern warfare across the planet.  相似文献   
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From 1955 to 1988, the Royal Australian Air Force (RAAF) maintained a large airbase in Northern Malaysia. For the first 15 years of its existence, RAAF Butterworth had a modest and incomplete perimeter fence. With the end of British military colonialism in Malaysia and Singapore following the implementation of the ‘East of Suez’ policy, the Australians became preoccupied with their physical security and the role of the perimeter fence. By exploring the adoption of practices of exclusion via physical barriers in the wake of British withdrawal, this paper argues that the changing psychological outlook of Australian military officials reflected broader Australian anxieties about their own sense of ‘Britishness’ and the nation’s place in a decolonising Asia. As the Australians lost their British ‘blanket’ they built a fence.  相似文献   
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This paper provides an analysis of images associated with the British Royal Air Force's recent ‘Be Part of the Story’ war comic-styled military recruiting campaign. Set around literatures in popular geopolitics, the paper builds on the concept of comic book visualities to suggest that the ‘Be Part of the Story’ images reproduce longstanding war comics conventions, and coherently represent the complex, relational and spatially disparate battlespaces of the present. The paper, firstly, provides a detailed history of war comics as they have mediated war to publics, and argues that war comics should figure more strongly in future studies of popular geopolitics. Secondly, it argues that more than simply part of a pervasive ‘cultural condition’ of militarization, military recruitment is a vital medium through which states and militaries view, and choose to represent their role in the world. Lastly, it demonstrates that ‘Be Part of the Story’ reproduces the violent visions, metaphors and cultural designations integral to state-centric narratives of global politics, and specifically, spatial principles inherent to network-centric warfare.  相似文献   
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考察古代人的结构力学认识,是对古建筑结构的分析及解释必不可少的研究之一。因为与现代建筑结构不同,古代建筑结构主要取决于当时工匠们的经验与直观判断。古代人对结构力学的认识概念,我们从中国古文献中可以看到。通过本研究发现,古代人已经有对力与荷重的力学认识以及古建筑的对称结构就是从古代力学的平衡概念出发而发展的。  相似文献   
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In Turkey, with the occurrence of almost every strong and even moderate earthquake, damage to masonry minarets is observed. In the present work, efficiency of vertical post-tensioning application to reinforce masonry minarets against earthquakes has been investigated. Considering a representative minaret and its post-tensioned counterpart, and performing spectral and time-history analyses, the effects of post-tensioning on the axial stresses, top lateral displacements and overturning safety have been determined. Obtained results have shown that vertical post-tensioning application is a very efficient method to reduce axial tensile stresses and lateral displacements, and to assure the overturning safety of masonry minarets against earthquakes.  相似文献   
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A displacement-based design (DBD) procedure for buildings equipped with different seismic isolation systems is proposed. It has been derived from the Direct Dispaced-Based Design (DDBD) method recently developed by Priestley et al. [2007] Priestley, M. J. N., Calvi, G. M. and Kowalsky, M. J. 2007. Displacement-Based Seismic Design of Structures, Pavia, , Italy: IUSS Press.  [Google Scholar]. The key aspect of the proposed procedure is the definition of a target displacement profile for the structure. It is assigned by the designer to achieve given performance levels, expressed in terms of maximum displacement of the isolation system and maximum interstory drift. The proposed design procedure has been developed for four different idealized force-displacement relationships, which can describe the cyclic response of a wide variety of isolation systems, including: (i) Lead-Rubber Bearings (LRB); (ii) High-Damping Rubber Bearings (HDRB); (iii) Friction Pendulum Systems (FPS); and (iv) Combinations of lubricated Flat Sliding Bearings (FSB) with different re-centering and/or energy dissipating auxiliary devices. In this article, the background and implementation of the design procedure is presented first. It is followed by the results of validation studies based on nonlinear time-history analyses on different design configurations of base isolated buildings.  相似文献   
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The first step in a hysteretic energy-based design approach of performance-based design is the estimation of hysteretic energy demand in the structure. A nonlinear response-history analysis of the multi-degree of freedom model gives an accurate estimation, but it is not suitable for adopting in design. Two alternative methods, based on the concepts of modal pushover analysis (MPA) and 2D-MPA, are proposed in this article for uniaxial plan-asymmetric structures. Application studies show that both methods are efficient. While the 2D-MPA-based method is more accurate, the MPA-based method is more suitable for design adoption. Significant conclusions are given for prospective application of these methods.  相似文献   
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This study is aimed at investigating the demand on shear panel dampers (SPDs) installed in steel structures under strong earthquake motions to serve as guidance for the recommended capacity of SPDs in seismic design. For this purpose, an extensive dynamic analysis is carried out on steel bridge pier structures with SPD devices. To describe the restoring force characteristics of SPDs, the analysis uses a newly developed combined hardening model based on experimental data. The seismic demands made on SPD devices are examined and then summarized to give recommended values for determining the necessary deformation capacity of SPDs.  相似文献   
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