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81.
This work uses the molecular dynamics approach to study the effects of functionalization of carbon nanotubes (CNTs) on the mechanical properties of Cu64Zr36 metallic glass (MG). Three types of functional groups, carboxylic, vinyl and ester were used. The effect of CNT volume fraction (Vf) and the number of functional groups attached to CNT, on the mechanical properties and thermal conductivity of CNT-MG composites was analysed using Biovia Materials Studio. At lower values of Vf (from 0 to 5%), the per-centage increase in Young's modulus was approximately 66%. As the value of Vf was increased further (from 5 to 12%), the rate of increase in Young's modulus was reduced to 16%. The thermal conductivity was found to increase from 1.52 W/mK at Vf=0%to 5.88 W/mK at Vf=12%, thus giving an increase of approximately 286%. Functionalization of SWCNT reduced the thermal conductivity of the SWCNT-MG composites. 相似文献
82.
本文介绍了一种用于测量材料在高应变率下单轴应力─应变性能的实验测量系统:落重与高速摄影实验系统。该系统在现有的落重装置的基础上,增加了高速摄影和应力过程的同时测量,使得在一次实验中可同时取到应力应变数据。从而避免了这类实验中常用的变形过程中体积不变的假设。通过高速实验提供的实验照片,我们还可以观察到聚合物在高应变率下从变形到断裂的发展过程。 相似文献
83.
This article presents a branch and bound method for solving the problem of minimizing a separable concave function over a convex polyhedral set where the variables are restricted to be integer valued. Computational results are reported. 相似文献
84.
Many optimization problems occur in both theory and practice when one has to optimize an objective function while an infinite number of constraints must be satisfied. The aim of this paper in to describe methods of handling such problems numerically in an effective manner. We also indicate a number of applications. 相似文献
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87.
Andrew J. Dowdle 《Small Wars & Insurgencies》2013,24(2):161-174
Previous research on African military spending suggests the existence of civil strife as the best predictor of high levels of military spending. However, little is known about why some African nations maintain strong ‘auxiliary’ or paramilitary organizations while others do not. This study finds that the presence of civil or interstate war does not strengthen reserve or irregular forces. Civilian governments promote strong paramilitary organizations to counter any threat the regular military might pose to regime survivability as a form of clientelist politics. 相似文献
88.
Ronald J Kurth Former President of the U.S. Naval War College 《战略研究杂志》2013,36(2):261-280
This article is a portrait of Admiral Sergei Gorshkov, commander of the Soviet Navy for almost three decades, from 1956–85. The author, a retired US Navy admiral with a Harvard PhD in Russian studies who served as both defense and naval attaché in Moscow, draws on numerous face-to-face interactions with Gorshkov. He also explores Gorshkov's memoirs that were published recently in Russia but have not appeared in an English translation. The paper is not only a first-hand account of an important historical figure, but also a window into the world of military-to-military diplomacy and intelligence during the Cold War. 相似文献
89.
A. S. Goldman 《海军后勤学研究》1969,16(1):111-120
Although industry is expected to design hardware to fit into a general support system and to be capable of arguing life-cycle system costs, adequate information has not been available on the support system in terms of policies and operating decision rules. Policies and operating decisions by users dominate engineering design decisions in determining life-cycle support costs. The relative effect of each of these decision areas on support costs has yet to be resolved empirically. Without an understanding of the sensitivity of support costs to alternative designs, capability is limited in design improvement and support of end items. Life-cycle costing of analysis under cost-effectiveness and the maintainability of integrated logistics support is open to question. 相似文献
90.
Jonathan Krause Thomas S. Wilkins Christopher Baxter P.M.H. Bell Vincent Boutet-Lehouillier Malcolm Hugh Patterson 《战略研究杂志》2013,36(1):145-158
Iain McCallum, Blood Brothers Hiram and Hudson Maxim: Pioneers of Modern Warfare. London: Chatham, 1999. Pp. 224, 33 illus., 2 maps, biblio., index. £20. ISBN 1–86176–096–5. Eric Ash, Sir Frederick Sykes and the Air Revolution, 1912–1918. London and Portland, OR: Frank Cass, 1999. Pp.xviii + 268, 20 illus., 3 maps, biblio., index. £42.50/$59.50 (cloth), £18.50/$27.50 (paper). ISBN 0–7146–4828–0 and ‐4382–3. Azar Gat, Fascist and Liberal Visions of War: Fuller, Liddell Hart, Douhet, and other Modernists. Oxford: Clarendon Press, 1998. Ppviii + 334, biblio., index. £45. ISBN 0–19–820715–8. David B. Woolner (ed.), The Second Quebec Conference Revisited: Waging War, Formulating Peace: Canada, Great Britain, and the United States in 1944–1945. Basingstoke; London: Macmillan Press, 1998. Pp.xiii + 210, index. £32.50. ISBN 0–333–75970–2. Jeffrey Grey. Up Top: The Royal Australian Navy and Southeast Asian Conflicts 1955–1972. St Leonards NSW: Allen &; Unwin in association with the Australian War Memorial, 1998. Pp.xx + 380, 110 illus., 12 tables, 23 maps &; diagrams, appendices, notes, biblio., index. NP. ISBN 1–86448–290–7. Susan L Carruthers, The Media at War. Basingstoke: Macmillan, 2000. Pp.321, biblio., index. £14.99 (paper). ISBN 0–333–69143–1, also available in hardback. Edward J. Marolda and Robert J. Schneller Jr, Shield and Sword: The United States Navy and the Persian Gulf War. Washington DC: Naval Historical Center, 1998. Pp.xxi + 517, 120 illus., 14 maps, biblio., index. NP. ISBN 0–1604–9476–1. Marvin Pokrant, Desert Shield at Sea: What the Navy Really Did and Desert Storm at Sea: What the Navy Really Did. Both Westport, CT: Greenwood Press, 1999. Pp.xxiii + 265,9 illus., biblio., index. £44.95. ISBN 0–313–31023–8. Pp.xxiv + 329,12 illus., biblio., index. NP. ISBN 0–313–31024–6. David Kaularich and Ronald C. Kramer, Crimes of the American Nuclear State: At Home and Abroad. Boston: Northeastern University Press, 1999. Pp.xviii + 195, biblio., index. £42.75. ISBN 1–55553–371‐X. Stanley Hoffmann, World Disorders: Troubled Peace in the Post‐Cold War Era. Lanham, MD: Rowman &; Littlefield, 1998. Pp.viii+279, notes, index. $29.95. ISBN 0–8476–8574–8. Lawrence Freedman (ed.), Strategic Coercion: Concepts and Cases. Oxford: Oxford‐University Press, 1998. Pp.400, index. £48. ISBN 0–19–829–349–6. Stephen J. Cimbala, Coercive Military Strategy. College Station, TX: Texas A&;M University Press, 1998. Pp.229, biblio, index; $39.95. ISBN 0–89096–836–5 相似文献