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61.
Subspace dynamic‐simplex linear interpolation search for mixed‐integer black‐box optimization problems
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Honggang Wang 《海军后勤学研究》2017,64(4):305-322
Design and management of complex systems with both integer and continuous decision variables can be guided using mixed‐integer optimization models and analysis. We propose a new mixed‐integer black‐box optimization (MIBO) method, subspace dynamic‐simplex linear interpolation search (SD‐SLIS), for decision making problems in which system performance can only be evaluated with a computer black‐box model. Through a sequence of gradient‐type local searches in subspaces of solution space, SD‐SLIS is particularly efficient for such MIBO problems with scaling issues. We discuss the convergence conditions and properties of SD‐SLIS algorithms for a class of MIBO problems. Under mild conditions, SD‐SLIS is proved to converge to a stationary solution asymptotically. We apply SD‐SLIS to six example problems including two MIBO problems associated with petroleum field development projects. The algorithm performance of SD‐SLIS is compared with that of a state‐of‐the‐art direct‐search method, NOMAD, and that of a full space simplex interpolation search, Full‐SLIS. The numerical results suggest that SD‐SLIS solves the example problems efficiently and outperforms the compared methods for most of the example cases. © 2017 Wiley Periodicals, Inc. Naval Research Logistics 64: 305–322, 2017 相似文献
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为了揭示关键几何参数对超声速膨胀器流动特性影响的规律,对3种隔板安装角和5种出进口面积比超声速膨胀器设计工况下的流场进行了数值研究。结果表明:随隔板安装角增加,斜激波向出口迁移,斜激波强度略有降低,超声速膨胀器膨胀比减小,效率提高;随出进口面积比增加,流道内高速区显著扩大并逐渐靠近压力面,斜激波增强,出口流动损失增加,超声速膨胀器膨胀比增大,效率降低。为获得综合性能较优超声速膨胀器结构,需在较小出进口面积比和较大隔板安装角之间做折衷选择。 相似文献
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Jason Ridler 《Defense & Security Analysis》2017,33(1):15-29
Insurgencies thrive in regions where government legitimacy is absent. In the post-war Philippines, Captain Charles T. R. Bohannan of the Army’s Counter Intelligence Corps became actively aware of this dynamic. Bohannan is best known for his later work with Edward Lansdale and Ramon Magsaysay in defeating the Huk Rebellion (1950–1954). Here the author examines Bohannan’s early investigative work against Japanese war criminals, wartime Filipino collaborators, and the rising threat of communist subversion most associated with the Huk. All of these experiences fed into what would be the successful campaign against the Huk, chronicled in his seminal work, Counter Guerrilla Operations: The Philippines Experience, and offers lessons on the investigative (as opposed to tactical or psychological) nature of effective counter-insurgency work, as it relates to both legitimacy in governance and the rise of insurgencies. 相似文献