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41.
Joseph O. Chapa 《Journal of Military Ethics》2017,16(3-4):256-271
In this paper I argue that a remotely piloted aircraft (RPA) pilot’s act of killing remotely, when it is done in the defense of another person, can be viewed as an act of sacrifice. This argument concludes from two premises. First, the RPA pilot faces psychological risk to self by carrying out such an action; second, the RPA pilot is motivated to some significant degree by something other than self-interest. Moreover, I challenge both the view that RPA represent merely an incremental development in technology yielding an incremental expansion of the distance between the war-fighter and the target and the view that RPA is revolutionary in some fundamental sense. I instead argue that, based upon the natural geometric boundary imposed by the earth’s shape, RPA have maximized the physical distance between the war-fighter and the target and, over time, this fact will change, not only the psychological effects on the RPA pilot, but also the way we view killing and distance in general. When taken together, these two broad claims, that other-defense can justify killing in war and that there is a psychological cost paid by remote killers, yield a conception of remote killing as an act of sacrifice that will inform the broader conversation about ethics, risk, killing, and RPA. 相似文献
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We consider the problem of scheduling a set of n jobs on a single batch machine, where several jobs can be processed simultaneously. Each job j has a processing time pj and a size sj. All jobs are available for processing at time 0. The batch machine has a capacity D. Several jobs can be batched together and processed simultaneously, provided that the total size of the jobs in the batch does not exceed D. The processing time of a batch is the largest processing time among all jobs in the batch. There is a single vehicle available for delivery of the finished products to the customer, and the vehicle has capacity K. We assume that K = rD, where and r is an integer. The travel time of the vehicle is T; that is, T is the time from the manufacturer to the customer. Our goal is to find a schedule of the jobs and a delivery plan so that the service span is minimized, where the service span is the time that the last job is delivered to the customer. We show that if the jobs have identical sizes, then we can find a schedule and delivery plan in time such that the service span is minimum. If the jobs have identical processing times, then we can find a schedule and delivery plan in time such that the service span is asymptotically at most 11/9 times the optimal service span. When the jobs have arbitrary processing times and arbitrary sizes, then we can find a schedule and delivery plan in time such that the service span is asymptotically at most twice the optimal service span. We also derive upper bounds of the absolute worst‐case ratios in both cases. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 470–482, 2015 相似文献
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Sheldon M. Ross 《海军后勤学研究》2015,62(8):659-663
There are n customers that need to be served. Customer i will only wait in queue for an exponentially distributed time with rate λi before departing the system. The service time of customer i has distribution Fi, and on completion of service of customer i a positive reward ri is earned. There is a single server and the problem is to choose, after each service completion, which currently in queue customer to serve next so as to maximize the expected total return. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 659–663, 2015 相似文献
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对某小型电动无人机(以下简称SEPUAV)在其左翼破损40%面积矩下的操稳特性进行详细分析。首先在此损伤下典型大侧滑角定常工作点附近进行特殊的小扰动线性化,然后进行特征根和飞行运动模态的分析;其次对此特殊构型SEPUAV进行操稳特性、时频响应特性进行分析。分析结果表明:左翼破损40%面积矩SEPUAV出现特有运动模态并影响全部纵侧向运动状态的响应;部分传递函数出现较多非最小相位零点从而导致初始响应发生反向;部分通道的Bode图中出现多个波峰波谷并有相角提前等现象。分析结果对后续容损飞行控制器的设计起到铺垫的作用。 相似文献
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采用伪谱法进行飞行器轨迹优化设计是近年来的热点研究方向,然而较全面地对各种方法进行综合分析的文献却很少。在对国内外相关文献进行系统研究的基础上,阐述了航空航天领域应用较为广泛的几种伪谱法的基本原理;归纳了伪谱法将连续最优控制问题转化为非线性规划问题的思路和具体步骤;总结了伪谱法在飞行器轨迹优化设计领域的应用情况;对伪谱法及其在飞行器轨迹优化设计领域应用的未来研究方向进行了分析。 相似文献
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