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81.
This paper investigates how individuals evaluate delayed outcomes with risky realization times. Under the discounted expected utility (DEU) model, such evaluations depend only on intertemporal preferences. We obtain several testable hypotheses using the DEU model as a benchmark and test these hypotheses in three experiments. In general, our results show that the DEU model is a poor predictor of intertemporal choice behavior under timing risk. We found that individuals are averse to timing risk and that they evaluate timing lotteries in a rank-dependent fashion. The main driver of timing risk aversion is nothing but probabilistic risk aversion that stems from the nonlinear treatment of probabilities.  相似文献   
82.
Supporting processes of belonging in supervision and coachingThe contemporary employee has to cope with frequent changes. Not only does he lose his familiar environment, he also has to find ways to familiarize himself with new places and to develop a fresh sense of belonging. This process can be understood and facilitated by interpreting the German concept of “Heimat“ as something we have to create ourselves. First experiences demonstrate the usefulness of this approach in coaching processes.  相似文献   
83.
In this paper, the task of determining expected values of sample moments, where the sample members have been selected based on noisy information, is considered. This task is a recurring problem in the theory of evolution strategies. Exact expressions for expected values of sums of products of concomitants of selected order statistics are derived. Then, using Edgeworth and Cornish-Fisher approximations, explicit results that depend on coefficients that can be determined numerically are obtained. While the results are exact only for normal populations, it is shown experimentally that including skewness and kurtosis in the calculations can yield greatly improved results for other distributions.  相似文献   
84.
继文献〔1〕的研究,针对激光于界面反射法定义及测定玻璃一个特性点时,双片玻璃试样熔接过程中的流变特性进行了理论分析,用简化的模型,探讨了上述方法的测定机制。  相似文献   
85.
以耕地“非粮化”面积达90%以上的Z市J区Y镇为案例,研究了政策碎片化对耕地“非粮化”的影响及其治理对策。研究发现,“单兵突进”的征地拆迁政策、“效力渐弱”的种粮补贴政策和“前后矛盾”的地方产业政策都是影响耕地“非粮化”的重要因素。建议从整体性视域出发,采取构建整体性政府行政机制以恢复农田系统、补贴政策由“种粮”向“收粮”转变、强化系统治理以统筹产业发展与耕地保护等治理对策,以有效解决耕地“非粮化”问题。  相似文献   
86.
以卫星光通信系统为例,对空间光通信系统中光学平台的抖动进行了分析。研究了一种自调节前馈补偿技术,通过自适应信号处理或对前馈控制器进行直接优化,可对光学平台的抖动进行有效抑制。  相似文献   
87.
对自由空间激光通信光束自动捕获、跟踪、瞄准(ATP)系统的结构与系统主要技术指标进行了分析和讨论。通过对其中典型系统的介绍,进一步描述了ATP技术的最新进展,论证了空间激光通信的可行性。  相似文献   
88.
结合重庆大学采矿工程学科研究生教育和培养的理论与实践,重点阐述对研究生培养及改革教学方式的有益探索,其成果为我国工科研究生培养提供了可借鉴的成功经验。  相似文献   
89.
Author of the highly acclaimed Borrowed Time: An AIDS Memoir (1988) and winner of the 1992 National Book Award for his autobiography Becoming a Man: Half a Life Story, Paul Monette died of complications from AIDS in Los Angeles on February 12, 1995. His most recent work, Last Watch of the Night: Essays Too Personal and Otherwise (1994), is his third volume in a trilogy of autobiographical writing on growing up gay, coming-out, and living with AIDS. A graduate of Phillips Academy and Yale University, Monette received a number of awards for his writing and his work as an outspoken voice in the battle against AIDS, including the National Book Award, three Lambda Literary awards, the PEN Center West Freedom to Write Award, and three honorary doctorate degrees, from Wesleyan University, the City University of New York, and the State University of New York at Oswego. A memorial service was held for Monette on Sunday, February 19, 1995, at the Directors Guild of America on Sunset Boulevard in Los Angeles. Paul Monette was 49.  相似文献   
90.
In the binary single constraint Knapsack Problem, denoted KP, we are given a knapsack of fixed capacity c and a set of n items. Each item j, j = 1,...,n, has an associated size or weight wj and a profit pj. The goal is to determine whether or not item j, j = 1,...,n, should be included in the knapsack. The objective is to maximize the total profit without exceeding the capacity c of the knapsack. In this paper, we study the sensitivity of the optimum of the KP to perturbations of either the profit or the weight of an item. We give approximate and exact interval limits for both cases (profit and weight) and propose several polynomial time algorithms able to reach these interval limits. The performance of the proposed algorithms are evaluated on a large number of problem instances.  相似文献   
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