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361.
碳化硼表面金属化初步研究   总被引:2,自引:0,他引:2  
为了降低碳化硼(B,C)与金属钎焊连接的温度,采用真空熔结Al基钎料的方法,在1000℃时对其进行了表面金属化处理,SEM和EDAX观察分析B4C与钎料结合断面的形貌和元素面分布,发现B4C与钎料界面发生了互扩散,界面结合致密,形成冶金结合.  相似文献   
362.
作为一体化联合作战体系中重要的陆基栅格节点,坦克分队的快速机动能力对于顺利完成机动突击任务具有重要影响,而坦克分队的机动协同控制则是实现分队快速机动的关键。首先提出一种坦克分队协同控制系统架构,然后对该架构的组成及关键技术进行了探讨和分析,期望有助于提升新型坦克分队的快速机动能力。  相似文献   
363.
汇编语言具有非结构化、非标准化、硬件相关性高、灵活性极大等特性,单元测试难度较大.针对汇编语言的特点,论述了汇编语言单元测试过程中功能测试、结构覆盖率测试和性能测试的方法和步骤.  相似文献   
364.
In a typical assemble‐to‐order system, a customer order may request multiple items, and the order may not be filled if any of the requested items are out of stock. A key customer service measure when unfilled orders are backordered is the order‐based backorder level. To evaluate this crucial performance measure, a fundamental question is whether the stationary joint inventory positions follow an independent and uniform distribution. In this context, this is equivalent to the irreducibility of the Markov chain formed by the joint inventory positions. This article presents a necessary and sufficient condition for the irreducibility of such a Markov chain through a set of simultaneous Diophantine equations. This result also leads to sufficient conditions that are more general than those in the published reports. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011  相似文献   
365.
建立了地空导弹武器系统效能综合评价的指标体系,利用模糊数学方法,确立了该系统的综合评价模型,从而为地空导弹武器系统效能的综合评价提供了一种方法,具有一定的参考价值。  相似文献   
366.
有限水深Kelvin源格林函数及其导数的快速计算   总被引:1,自引:0,他引:1  
应用线性船舶水动力学理论,将有限水深Kelvin移动兴波源格林函数分解成3部分:简单Rankine源集合、局部扰动项和波函数项。对各部分在亚临界和超临界航速时的快速计算分别作了讨论,其中对计算费时的局部扰动项采用了复数中的最陡下降积分法,加快了计算速度,进而引出各部分偏导数的计算。最后,比较了格林函数的差分值与偏导数值,计算了薄船兴波阻力与表面兴波,讨论了不同面元网格划分的收敛性,证实了亚临界、超临界航速兴波分别以横波、散波为主。  相似文献   
367.
模块化油料装备具有运用方式灵活、功能模块扩展能力强的优点,既能使油料装备的保障能力显著增强,又方便设计、制造、使用和维修,但各模块单元之间不易实现干式快速连接与分离。为实现油料装备模块单元快速连接、拆卸且无油料漏出,创新设计一种干式快速自封连接接头。该接头用于油料装备模块单元连接时,管路系统能自动接通;各模块单元分离时,管路系统能自动封闭,使各模块单元或组合体形成一个密封体,始终无漏油现象。该干式快速自封连接接头用于模块单元连接或分离,具有简便、快捷且无油料渗出等特点。  相似文献   
368.
建筑表皮可以传承文化,反映特定时期的气候特征、地域文化、生活方式、美学及科学技术等,而建筑表皮设计则直接表达建筑师的设计意图,建筑表皮造型设计创意对建筑设计至关重要。从建筑表皮的形态构成、视觉效果和创意表达等3个方面阐述现代建筑表皮,提示建筑师灵活运用点、线、面、体、材质与色彩这些基本造型元素能设计不同的建筑表皮造型,表达不同的艺术思想,取得不同的视觉效果。  相似文献   
369.
The purpose of this paper is to investigate the problem of constructing an appointment template for scheduling patients at a specific type of multidisciplinary outpatient clinic called an integrated practice unit (IPU). The focus is on developing and solving a stochastic optimization model for a back pain IPU in the face of random arrivals, an uncertain patient mix, and variable service times. The deterministic version of the problem is modeled as a mixed integer program with the objective of minimizing a weighted combination of clinic closing time (duration) and total patient waiting time (length of stay). A two‐stage stochastic program is then derived to account for the randomness and the sequential nature of the decisions. Although it was not possible to solve the two‐stage problem for even a limited number of scenarios, the wait‐and‐see (WS) problem was sufficiently tractable to provide a lower bound on the stochastic solution. The introduction of valid inequalities, limiting indices, and the use of special ordered sets helped to speed up the computations. A greedy heuristic was also developed to obtain solutions much more quickly. Out of practical considerations, it was necessary to develop appointment templates with time slots at fixed intervals, which are not available from the WS solution. The first to be derived was the expected value (EV) template that is used to find the expected value of the EV solution (EEV). This solution provides an upper bound on the objective function value of the two‐stage stochastic program. The average gap between the EEV and WS solutions was 18%. Results from extensive computational testing are presented for the EV template and for our adaptation of three other templates found in the literature. Depending on the relative importance of the two objective function metrics, the results demonstrate the trade‐off that exists between them. For the templates investigated, the “closing time” ranged from an average of 235 to 275 minutes for a 300‐minute session, while the corresponding “total patient time in clinic” ranged from 80 to 71 minutes.  相似文献   
370.
The current combat motivation model based on primary group thesis assumes that the main force behind motivation is peer-bonding or otherwise known as unit cohesion. Cohesion is perceived as an all-encompassing factor that leads to satisfactory (or unsatisfactory in lack thereof) military effectiveness and performance in conflict environments. However, the article identifies three main problems with this perspective: 1. mono-dimensional view of motivation; 2. motivation based on heteronomy, and 3. self-reporting bias. The current model does not consider motivation as a separate entity from cohesion; it does not place motivation as fundamental human value; lastly, it takes motivation as granted by-product of socialization. The article proposes a new combat motivation model based on The Self-Determination Theory. The theory maintains that human motivation requires satisfaction of three psychological needs of competence, relatedness, and autonomy. The degree of satisfaction of those three needs leads to different types of regulated motivations – a continuum from intrinsic to extrinsic – each of which has specifiable consequences for learning, performance, and well-being of an individual.  相似文献   
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