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21.
Shib Sankar Sana 《Applied mathematics and computation》2011,218(7):3277-3288
The paper deals with an inventory model to determine the retailer’s optimal order quantity for similar products. It is assumed that the amount of display space is limited and the demand of the products depends on the display stock level where more stock of one product makes a negative impression of the another product. Besides it, the demand rate is also dependent on selling price and salesmen’s initiatives. Also, the replenishment rate depends on the level of stock of the items. The objective of the model is to maximize the profit function, including the effect of inflation and time value of money by Pontryagin’s Maximal Principles. The stability analysis of the concerned dynamical system has been done analytically. 相似文献
22.
针对初始排污权总量分配的实际问题,基于统一价格拍卖的思想提出了一种具有激励性的可变总量的分配方法,分别给出了排污企业对称和排污企业非对称两种情形下的线性均衡报价策略,并证明了该方法的可行性和有效性,从而为建设排污权分配和交易制度提供了理论依据和方法参考. 相似文献
23.
仿真实验分析是研究交易系统规律的一种重要手段,带约束的零智能系统(ZI-C)是业界研究双向交易系统的重要基准.本文针对ZI-C的典型仿真实验进行分析,揭示其中系统内价格出清过程和实验设置的关系,并量化了各交易者在市场匹配中的难易程度.在分析中,首次提出了一种概率仿真模型,使用了迭代计算来估计每一时刻系统中各种价格产生的... 相似文献
24.
Young′s moduli of various epoxy coated polyethylene terephthalate (PET) micro-cantilevers were determined from the deflection results obtained using the phase-shift shadow moiré (PSSM) method. The filler materials for epoxy coatings were aluminum and graphite powders that were mixed with epoxy at various percentages. Young′s moduli were calculated from theory based on the deflection results. The PET micro-cantilever coated with aluminum-epoxy coating showed increasing value of Young′s modulus when the ratios of the aluminum-epoxy were increased. The graphite-epoxy coating on the PET micro-cantilever also showed the same trend. The experimental results also show that Young′s modulus of the graphite-epoxy coating is higher than aluminum-epoxy coating in comparison at the same mixing ratio. 相似文献
25.
通过实验研究了在气流冲击下水面的凹陷情况,并通过理论计算予以解释.结果表明凹陷的体积和深度主要与气流速度、玻璃管内径和玻璃管底部到水面上的距离有关的结论. 相似文献
26.
We calculate photon sphere \begin{document}$r_{ph}$\end{document} ![]()
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and critical curve \begin{document}$b_c$\end{document} ![]()
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for a quantum corrected Schwarzschild black hole, finding that they violate universal inequalities proved for asymptotically flat black holes that satisfy the null energy condition in the framework of Einstein gravity. This violation seems to be a common phenomenon when considering quantum modification of Einstein gravity. Furthermore, we study the shadows, lensing rings, and photon rings in the quantum corrected Schwarzschild black hole. The violation leads to a larger bright lensing ring in the observational appearance of the thin disk emission near the black hole compared with the classical Schwarzschild black hole. Our analysis may provide observational evidence for the quantum effect of general relativity. 相似文献
27.
The paper formulates an extension of the traveling purchaser problem where multiple types of commodities are sold at spatially distributed locations with stochastic prices (each following a known probability distribution). A purchaser’s goal is to find the optimal routing and purchasing strategies that minimize the expected total travel and purchasing costs needed to purchase one unit of each commodity. The purchaser reveals the actual commodity price at a seller upon arrival, and then either purchases the commodity at the offered price, or rejects the price and visits a next seller. In this paper, we propose an exact solution algorithm based on dynamic programming, an iterative approximate algorithm that yields bounds for the minimum total expected cost, and a greedy heuristic for fast solutions to large-scale applications. We analyze the characteristics of the problem and test the computational performance of the proposed algorithms. The numerical results show that the approximate and heuristic algorithms yield near-optimum strategies and very good estimates of the minimum total cost. 相似文献
28.
物价、利率与收入对居民消费需求影响研究——基于时变参数状态空间模型 总被引:1,自引:0,他引:1
运用时变参数状态空间模型对我国改革开放三十年来物价、利率与收入对农村和城镇居民消费需求影响的动态特征进行了研究。发现物价、收入对农村和城镇居民的消费需求弹性不同,农村消费需求受收入影响较大,而城市居民消费需求受物价影响较大;利率对农村和城镇居民消费需求影响不显著,利率机制目前还不是调解中国消费需求的理想工具。在此基础上给出了相应的政策建议。 相似文献
29.
In this paper, we introduce a valuation model of callable warrants under a setting of the optimal stopping problem between the holder (investor) and the issuer (firm). A warrant is the right to purchase new shares at a predetermined price. When the new stocks are issued, the value of the stock is diluted. We consider the model taking the dilution into account. After identifying optimal policies for the issuer and the investor, we explore the analytical properties of the optimal exercise and call boundaries for the holder and the issuer, respectively. Furthermore, the value of such a callable warrant and the optimal critical prices are examined numerically using the binomial method. 相似文献
30.
介绍了福建省目前的分时电价政策.基于冷库实例,模拟计算了制冷装置增加夜间运行时间,采用不同蓄冷运行方案的运行费用.结果显示,理想条件下冷库的运行电费可节省47.3%以上,现场调研的某冷库运行电费可减少约31%.根据气象台的逐时气象数据统计,厦门市夜间湿球温度下降1.2~1.8℃.计算表明,制冷装置夜间运行的COP因此比... 相似文献