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931.
《European Journal of Operational Research》2005,163(3):688-705
The role of remanufacturing as a competitive tool for firms has been reflected in a number of studies to show that remanufacturing can reduce the unit cost of production by reusing components. However, the fact that remanufacturing can be used as a strategic tool for serving secondary markets as well has not been acknowledged in the literature. In this paper, we study the use of remanufacturing as a tool to serve secondary markets. Specifically, we model the case of a reseller who procures used products based on an older generation of technology from an advanced market and then uses one of two options: (a) she can either resell a small fraction of these used products in a developing market where the technology is acceptable, or (b) she can invest in the remanufacturing of these products and then sell them in the developing market at a higher price. The main result of the paper is that using remanufacturing to serve secondary markets reduces the number of units procured from the advanced market for the reseller. In addition, we show based on certain cost structures that the reseller is always better off if she uses remanufacturing to a certain extent. 相似文献
932.
关于MQ算法的松驰因子 总被引:1,自引:0,他引:1
In this paper, a new method, so called A-method, is given for the convergence analysis of the MQ-algorithm. And the finer relaxation parameter θA is obtained. The numerical results show that our new method has the outstanding effect of accelerating convergence. Moreover, the relaxation parameter θA is the optimum in a point of view. 相似文献
933.
934.
§1IntroductionThe generalized Ball curves possess many properties similar to the properties of Béziercurve and an advantage that there are more efficient elevation and recursive algorithms forevaluating the points on curve[1-3].The dual functionals are an important tool forconversing various bases and studying the properties of curve and surface.Lai gave thedual functionals of polynomials in B-form or in Bézier form over a simplex[4].In theunivariate setting the dual functionals of variou… 相似文献
935.
在以往的(t,n)秘密共享模式中,为了使接收者能够重构消息,n个验证者之间需要广播消息密文影子(shadow).本文提出了一种新的(t,n)秘密共享模式,在该模式中,验证者之间无需广播秘密影子,从而大大地减少了网络的通信量,提高了安全性.此外,该模式具有密钥和消息认证功能,不仅能够有效地抵抗假冒攻击,还能够识别验证者的欺骗行为. 相似文献
936.
《European Journal of Operational Research》2006,174(2):1076-1086
In this paper we extend the work of [Färe and Zelenyuk , 2003. On aggregate farrell efficiency scores. European Journal of Operational Research 146(3) 615–620] to find a theoretically justified method of aggregating Malmquist Productivity Indexes over individual decision making units (firms, countries, etc.) into a group Malmquist Productivity Index. We also consider the aggregation of decomposed parts of the Malmquist Productivity Index to obtain a decomposition of the Malmquist Productivity Index for a particular group. 相似文献
937.
938.
Consider a dominant manufacturer wholesaling a product to a retailer, who in turn retails it to the consumers at $p/unit. The retail-market demand volume varies with p according to a given demand curve. This basic system is commonly modeled as a manufacturer-Stackelberg ([mS]) game under a “deterministic and symmetric-information” (“det-sym-i”) framework. We first explain the logical flaws of this framework, which are (i) the dominant manufacturer-leader will have a lower profit than the retailer under an iso-elastic demand curve; (ii) in some situations the system’s “correct solution” can be hyper-sensitive to minute changes in the demand curve; (iii) applying volume discounting while keeping the original [mS] profit-maximizing objective leads to an implausible degenerate solution in which the manufacturer has dictatorial power over the channel. We then present an extension of the “stochastic and asymmetric-information” (“sto-asy-i”) framework proposed in Lau and Lau [Lau, A., Lau, H.-S., 2005. Some two-echelon supply-chain games: Improving from deterministic–symmetric-information to stochastic-asymmetric-information models. European Journal of Operational Research 161 (1), 203–223], coupled with the notion that a profit-maximizing dominant manufacturer may implement not only [mS] but also “[pm]”—i.e., using a manufacturer-imposed maximum retail price. We show that this new framework resolves all the logical flaws stated above. Along the way, we also present a procedure for the dominant manufacturer to design a profit-maximizing volume-discount scheme using stochastic and asymmetric demand information. 相似文献
939.
The confined space produced during the polymerization has access for all small organic molecules or oligomers with small size to enter this confined space; however, it can prevent the macromolecules with big size from entering. Therefore, the reaction between two branched macromolecules is excluded in A2+B3 polymerization system, resulting uncrosslinked branched polymers, and there was no gel point observed throughout the polymerization. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1730–1737, 2008 相似文献
940.
Yunsheng Ding Renyan Xiong Sengshan Wang Xiaomin Zhang 《Journal of Polymer Science.Polymer Physics》2007,45(11):1252-1259
A series of organomontmorillonites were synthesized from pristine sodium montmorillonite via ion exchange in toluene with 1‐octadecyl‐3‐methylimidazolium chloride, a kind of ionic liquid with high thermal stability, as a modifier. The amount and aggregative state of the 1‐octadecyl‐3‐methylimidazolium cation ([C18mim]+) adsorbed in the interlayer of organomontmorillonite (MMT) were investigated with thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy, X‐ray diffraction (XRD), and differential scanning calorimetry. XRD patterns showed that [C18mim]+ was successfully intercalated into the interlayer of MMT, and the interlayer distances of the clays increased dramatically. On the basis of the TGA results, three types of arrangement models of [C18mim]+ could be seen, and they were related to the loading level of [C18mim]+ in the gallery of MMT. The effects of the aggregative structure of [C18mim]+ in the interlayer of MMT on polypropylene melt intercalation was also examined. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1252–1259, 2007 相似文献