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391.
This study investigates the ricochet behaviour of three different small-arms projectile types using a novel ricochet measuring device.The results can be used to estimate the danger potential of ricochets on shooting ranges.A ricochet is the change of direction and velocity of a projectile after impacting an oblique surface.This impact produces strong vibrations on a rigid plate.During this impact,flexural waves travel radially outwards from the point of impact.These waves are used to determine the properties of the impactor with accelerometers situated on the target surface.With the use of two measurement plates,one can produce a ricochet and detect the velocity at the same time.Accelerometers are suitable for accurate momentum measurements of single impacts.However,depending upon strike velocity and the impact angle,a ricochet can separate in multiple fragments after being deflected.From the operational safety perspective,these fragments need to be detected,as well.The approach of a coupled sensor concept was chosen to solve this problem.Thermographic sensors were additionally used to visualise the heat which is produced after pene-trating a rubber layer pasted in front of the steel target plate.With this approach one was able to detect the position of impact.The investigations showed that the measurement system performance is better with a multiple sensor design,which includes accelerometers for the velocity,impact strength and partly the position measurement,while the thermographic sensor was used for the position measurement and partly the momentum measurement.The investigated ammunition showed plausible fragmentation behaviour,and the results can already be used to estimate the danger potential of different ammunition types.Frangible projectiles fragment to small particles already after being deflected under a small angle.However,Full Metal Jacket projectiles with or without a steel core do not fragment under angles which are less than 5°.The objective of the paper is to demonstrate the possibility of measuring the complex ricochet me-chanics of small projectiles using standard accelerometers with the adequate signal processing approach.This measuring system is supported by an off the shelf thermographic camera. 相似文献
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Phillips P. O'Brien 《战略研究杂志》2013,36(2):89-113
One of the most commonly expressed opinions about victory in the Second World War is that the Soviet Union was mostly responsible for beating Nazi Germany. Supposedly the great land war fought between these two powers in the East was the decisive front in Europe. The West's contribution to German defeat, on the other hand, is often seen as somewhat marginal. The Anglo‐American strategic bombing campaign in 1943 paid few dividends and it was not until after the Normandy landings in June 1944 that the West really began to divert a large amount of German resources. The purpose of this article is to challenge some of these basic notions. Through analysing what Germany produced, where it was sent and how it was destroyed, the West's contribution to defeating Germany moves from an ancillary position to a dominant one. Taking German war production as a whole, from 1943 onwards the West was responsible for tying down and destroying a significantly larger share than the Soviet Union. 相似文献
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Michael Cohen 《战略研究杂志》2013,36(2):152-183
This article contributes yet another perspective to the Suez War – the strategic and military planning carried out since the end of the Second World War by the Western Allies for the contingency of a new world conflict against the Soviet bloc. The Middle East was of vital strategic significance. Colonel Nasser's announcement of the Czech arms deal in September 1955 triggered the countdown to a new war in the region. London and Washington urgently drew up contingency plans for intervention, both with economic sanctions and armed force. Joint staff talks were held in Washington from March to August 1956. They were halted just two months before the United Kingdom decided to collude with France and Israel to attack Egypt. 相似文献
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Future conflict between armed forces will occur both in the physical domain as well as the information domain. The linkage of these domains is not yet fully understood. We study the dynamics of a force subject to kinetic effects as well as a specific network effect–spreading malware. In the course of our study, we unify two well‐studied models: the Lanchester model of armed conflict and deterministic models of epidemiology. We develop basic results, including a rule for determining when explicit modeling of network propagation is required. We then generalize the model to a force subdivided by both physical and network topology, and demonstrate the specific case where the force is divided between front‐ and rear‐echelons. © 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013 相似文献
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John P. Sullivan 《Small Wars & Insurgencies》2013,24(1):82-96
The nature of conflict and crime is changing. Technology allows groups to spread their influence without regard to geographic limitations. A shift from hierarchies to network organizational forms is also occurring. As a consequence non‐state actors can extend their influence to gain social, political or economic power and challenge state institutions. This article examines the potential for gangs, transnational criminals and terrorists to embrace network forms and utilize technology to wage netwar. Factors which influence ‘third generation’ gang organization (politicization, internationalization and sophistication) are described to illustrate how a net‐based threat can mature. A move toward network organization within transnational criminal organizations and terrorist groups demonstrating the potential for these classic criminal entities to emerge as netwar actors is also reviewed. Finally, the need for state institutions such as the police and military to develop networked responses to combat networked threats is stated. 相似文献