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371.
针对BTT导弹在飞行过程中模型存在较大不确定性,并且控制舵的摆角受到物理装置约束的情况,研究了在约束条件下导弹姿态跟踪保性能控制的设计问题。首先在弹道的特征点处将导弹的非线性运动瞬时线性化,将导弹看作是一个不确定线性系统,提出应用基于线性矩阵不等式的跟踪保性能控制设计姿态控制器,然后推导得到满足控制约束的充分条件,以定理的形式给出了约束条件下跟踪保性能控制存在的充分条件。最后以某型导弹的姿态控制为例,设计了其姿态的跟踪保性能控制器。六自由度仿真结果表明了所得方法的有效性和可行性。 相似文献
372.
针对隧道出入口段照明能耗大、行车舒适性差的缺点,依据隧道外亮度传感器采集的数据,通过单片机分组控制出入口段照明灯具,满足车辆出入隧道时驾驶员的明适应和暗适应需要。该法不但提高了驾驶舒适性,而且减少了能耗,降低了运营费用。 相似文献
373.
《防务技术》2022,18(11):1935-1944
This paper studies electromagnetoelastic static investigation of a sandwich doubly curved microshell subjected to multi-field loading based on a new thickness stretching included refined higher order shear/normal deformable model. Modified-couple-stress-theory (MCST) is used for accounting small-scale-dependency. The numerical results are derived using an analytical method. The effect of small scale parameter in micro scale, initial electric and magnetic potentials and foundation parameters is studied on the electromagnetoelastic bending results. It is confirmed an enhancing in stiffness of small scale shell with an increase in micro length scale parameter. 相似文献
374.
坦克铅酸蓄电池快速充电模糊控制研究 总被引:2,自引:0,他引:2
对于坦克用铅酸蓄电池快速充电问题,初步研究了采用模糊控制器控制充电过程,分析了其模糊控制器的组成,并讨论了模糊控制在铅酸蓄电池快速充电中存在的问题。 相似文献
375.
介绍了一种采用PLC控制器对等离子喷涂工艺流程进行监控的应用实例.在分析等离子喷涂工艺要求的基础上,设计出喷涂的PLC控制时序,并以此为依据完成PLC电路及软件设计.采用PLC控制,简化了喷涂工艺操作,提高了喷涂效率和涂层质量. 相似文献
376.
When facing high levels of overstock inventories, firms often push their salesforce to work harder than usual to attract more demand, and one way to achieve that is to offer attractive incentives. However, most research on the optimal design of salesforce incentives ignores this dependency and assumes that operational decisions of production/inventory management are separable from design of salesforce incentives. We investigate this dependency in the problem of joint salesforce incentive design and inventory/production control. We develop a dynamic Principal‐Agent model with both Moral Hazard and Adverse Selection in which the principal is strategic and risk‐neutral but the agent is myopic and risk‐averse. We find the optimal joint incentive design and inventory control strategy, and demonstrate the impact of operational decisions on the design of a compensation package. The optimal strategy is characterized by a menu of inventory‐dependent salesforce compensation contracts. We show that the optimal compensation package depends highly on the operational decisions; when inventory levels are high, (a) the firm offers a more attractive contract and (b) the contract is effective in inducing the salesforce to work harder than usual. In contrast, when inventory levels are low, the firm can offer a less attractive compensation package, but still expect the salesforce to work hard enough. In addition, we show that although the inventory/production management and the design of salesforce compensation package are highly correlated, information acquisition through contract design allows the firm to implement traditional inventory control policies: a market‐based state‐dependent policy (with a constant base‐stock level when the inventory is low) that makes use of the extracted market condition from the agent is optimal. This work appears to be the first article on operations that addresses the important interplay between inventory/production control and salesforce compensation decisions in a dynamic setting. Our findings shed light on the effective integration of these two significant aspects for the successful operation of a firm. © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 320–340, 2014 相似文献
377.
378.
李陆冀 《海军工程大学学报》1994,(1)
本文建立了基线修正误差分析的数学模型,并对舰炮火控系统中应用的传统的近似基线修正方法进行了深入的分析。通过分析,作者指出:在现代中、小口径舰炮火控系统中,不能再沿用传统的近似基线修正方法,必须进行精确的基线修正。 相似文献
379.
Notwithstanding the embrace of modern institutions of social control, traditional social control mechanisms still enjoy patronage in Nigeria. This paper examines the traditional structures of social control in Iraye-Oke, Lagos. In-depth interviews, key informant interviews and case studies were used to obtain data from participants. Findings established the functionality of traditional structures in checking crime and its preference over the use of modern social control structures. Traditional structures used include: traditional spiritualists who provide measures to reduce victimisation; the family courts where adjudication takes place involving elders and family chiefs; and the apex traditional court, presided over by the king, where cases like murder, land disputes, adultery and fornication are decided. Traditional extrajudicial measures involve the invocation of ancestral spirits at shrines. 相似文献
380.
The efforts of President Barack Obama and his administration to restore the United States as a driving force of multilateral arms control and nonproliferation negotiations are commendable, yet the lack of progress on such issues over the last eight years has ensured that U.S. policy has not kept pace with changes in the geostrategic environment and the evolving security agenda. Meanwhile, an alternative agenda has been articulated by non-Western countries. This article focuses on the arms control perspectives of Non-Aligned Movement states and others that have begun to embrace the idea of “disarmament as humanitarian action.” It explores this idea in the context of recent initiatives and argues that if the Obama administration wants to make progress on its arms control and nonproliferation priorities, it should consider a multifaceted approach that incorporates this emerging alternative agenda. 相似文献