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21.
The route planning of time-sensitive air-cargo is becoming more important with the growing air-network congestion and delays. We consider a freight forwarder’s routing of a time-sensitive air-cargo in the presence of real-time and historical information regarding flight availability, departure delays and travel times. A departure delay estimation model is developed to account for real-time information inaccuracy. A novel Markov decision model is formulated and solved with online backward induction. Through synthetic experiments and case studies, we demonstrate that dynamic routing with real-time information can improve delivery reliability and reduce expected cost.  相似文献   
22.
本文建立了一类具有无界时滞微分不等式,将有界时滞微分不等式推广到无界时滞微分不等式,并得到其解的指数估计和渐近估计.  相似文献   
23.
孟杰  刘艳 《价值工程》2012,31(7):31
为解决工厂长明灯现象,设计了一种声光双控节能电路供楼道照明灯用,其功能:夜间有人上下楼时,照明灯自动点亮,灯亮后延时2~3分钟,会自动熄灭;白天照明灯受人走动的控制,灯不会点亮。整个电路由电源电路,放大电路,处理电路(声控电路、光控电路)及延时电路等部分组成。  相似文献   
24.
In order to predict airline responses to Traffic Management Initiatives (TMIs), and reveal the underlying preference structures that shape these responses, we study US domestic airlines’ cancellation decisions in response to the Federal Aviation Administration (FAA)’s TMIs, in particular, to Ground Delay Programs (GDPs). By observing the actual flight-cancellation choices made by airline dispatchers, the airlines’ cancellation utility functions can be inferred through the use of binary choice models. The model captures how delays to a given flight and potential delay savings to other flights affect flight cancellation decisions. We also find larger, fuller, less frequent, shorter-distance, and spoke-bound flights are less likely to be cancelled, and that there is inter-airline variation in flight cancellation behaviour.  相似文献   
25.
Controlled laboratory conditions using monetary incentives have been utilized in previous studies that examine individual discount rates, and researchers have found several apparently robust anomalies. We conjecture that subject behavior in these experiments may be affected by (uncontrolled) factors other than discount rates. We address some experimental design issues and report a new series of experiments designed to elicit individual discount rates. Our primary treatments include: (i) informing subjects of the annual and effective interest rates associated with alternative payment streams, and (ii) informing subjects of current market interest rates. We also test for the effect of real (vs. hypothetical) payments and for the effect of delaying both payment options (vs. offering an immediate payment option). The statistical analysis uses censored data techniques to account for the interactions between field and lab incentives. Each of the information treatments appears to reduce revealed discount rates. When both types of information are provided, annual rates in the interval of 15%–17.5% are revealed, whereas rates of 20%–25% are revealed in the control session. Each of the treatments also lowers the residual variance of subject responses.  相似文献   
26.
张瑞 《价值工程》2011,30(28):133-134
研究了区间时变时滞线性系统的稳定性问题,基于Lyapunov泛函方法,使用新的处理技术估计Lyapunov泛函导数的上界,以线性矩阵不等式形式给出了系统稳定性准则的改进结果。所给稳定性准则比已有结果具有更低的保守性,数值实例表明了结果的有效性。  相似文献   
27.
王盛明  卢秉亮 《价值工程》2011,30(10):152-153
基于LDD的预取策略如DDP考虑了数据距离,但是没有考虑数据的访问概率和更新频率和数据大小,针对以上问题提出基于价值的数据预取(CDP)策略,一些重要的数据预取因素如访问概率、更新频率、数据项大小、数据距离和有效范围等都包含在价值函数里,根据价值函数值的大小来选择被预取的数据。通过实验对比,CDP比DDP策略更有效的提高缓存的命中率。  相似文献   
28.
We use a framed field experiment considering hypothetical stocking rate decisions made by grazing enterprise managers and estimate non‐linear multinomial logit models for a range of nested non‐expected utility and expected utility models. The risk and decision‐bias parameters for five models estimated for individual responses are shown to be significantly related to land condition but in ways which suggest behavioural aspects of decision making are critical in understanding land management and stocking rate decisions. Our results show that individual heterogeneity in decision making amongst farming groups is likely to be a significant source of variation in farming intensity and technology adoption decisions. This heterogeneity does not appear to be a reflection of socio‐demographic characteristics. Furthermore, decision functions appear to be biased toward selection of simpler representative functions (e.g. Expected Utility) for sample averages. This suggests that experimental findings that Expected Utility is representative for actual decisions may be due to sample averaging rather than reflect actual behaviour.  相似文献   
29.
In a discounted one-sector convex model of optimal economic growth where utility may depend on both consumption and capital stock, I derive necessary and sufficient conditions for sustained growth (unbounded expansion of capital and consumption). Conditions for bounded growth and extinction are also outlined. Optimal paths may be non-monotone. Sustained growth may occur even though the asymptotic marginal productivity is less than the discount rate and may require the initial capital stock to be above a critical level. The behavior of the marginal rate of substitution between consumption and capital plays a crucial role in the conditions.  相似文献   
30.
A renewal equation approach is proposed to derive the multiple special-cause cost model for a system with two dependent subprocesses. The economic individual X control chart and simple cause-selecting control chart are thus constructed to monitor the two subprocesses. They may be used to maintain the whole process with minimum cost and effectively distinguish which component of the subprocesses is out of control. The economic design parameters of these two control charts can be determined by minimizing the cost model using a simple grid search method. An example of its application on controlling service quality in the bank industry is given to illustrate the design procedure and its application. It shows that these control charts may be used to control not only manufacturing dependent subprocesses but also service organisations with dependent subprocesses.  相似文献   
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