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991.
We consider a noncooperative differential game where a retailer sells her own private label in addition to the manufacturer’s brand. We assume that each brand’s goodwill evolves according to a modified Nerlove-Arrow dynamics, in such a way that the advertising effort of one brand hurts the competitor’s goodwill stock. We characterize Feedback-Stackelberg pricing and advertising strategies and employ simulations to analyze their sensitivity to the main model parameters. We thank an anonymous Reviewer for very helpful comments. Research supported by NSERC, Canada, and FQRSC, Quebec. Research completed when the second author was a visiting professor at GERAD, HEC Montréal. The second author’s research was partially supported by MEC and JCYL under projects SEJ2005-03858/ECON and VA045A06, co-financed by FEDER funds.  相似文献   
992.
993.
Errata-corrige     
Rendiconti del Circolo Matematico di Palermo Series 1 -  相似文献   
994.
    
This short paper addresses both researchers in multiobjective optimization as well as industrial practitioners and decision makers in need of solving optimization and decision problems with multiple criteria. To enhance the solution and decision process, a multiobjective decomposition-coordination framework is presented that initially decomposes the original problem into a collection of smaller-sized subproblems that can be solved for their individual solution sets. A common solution for all decomposed and, thus, the original problem is then achieved through a subsequent coordination mechanism that uses the concept of epsilon-efficiency to integrate decisions on the desired tradeoffs between these individual solutions. An application to a problem from vehicle configuration design is selected for further illustration of the results in this paper and suggests that the proposed method is an effective and promising new solution technique for multicriteria decision making and optimization. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
995.
    
We consider in this work general curved rods with a circular cross‐section of radius δ. Our aim is to study the asymptotic behaviour of such rods as δ→0, in the framework of the linear elasticity according to the unfolding method. It consists in giving some decompositions of the displacements of such rods, and then in passing to the limit in a fixed domain. A first decomposition concerns the elementary displacements of a curved rod which characterize its translations and rotations, and the residual displacements related to the deformation of the cross‐section. The second decomposition concerns the displacements of the middle‐line of the rod. We prove that such a displacement can be written as the sum of an inextensional displacement and of an extensional one. An extensional displacement will modify the length of the middle‐line, while an inextensional displacement will not change this length in a first approximation. We show that the H1‐norm of an inextensional displacement is of order 1, while that of an extensional displacement is in general, of order δ. A priori estimates are established and convergence results as δ→0, are given for the displacements. We give their unfolded limits, as well as the unfolded limits of the strain and stress tensors. To prove the convergence of the strain tensor, the introduction of elementary and residual displacements appears as essential. By passing to the limit as δ→0 in the linearized system of the elasticity, we obtain on the one hand, a variational problem that is satisfied by the limit extensional displacement, and on the other hand, a variational problem coupling the limit of inextensional displacements and the limit of the angle of torsion. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
996.
    
Computational Management Science -  相似文献   
997.
This paper is devoted to describing the asymptotic behavior of a structure made by a thin plate and a thin perpendicular rod in the framework of nonlinear elasticity. The authors scale the applied forces in such a way that the level of the total elastic energy leads to the Von-K′arm′an’s equations (or the linear model for smaller forces) in the plate and to a one-dimensional rod-model at the limit. The junction conditions include in particular the continuity of the bending in the plate and the stretching in the rod at the junction.  相似文献   
998.
999.
A study of the effect of excluded volume on the mean-square optical anisotropy 〈γ2〉 and the mean-square end-to-end distance 〈R2〉 has been carried out for polymer chains of up to 2000 bonds. The calculations have been made for models assuming (a) equiprobability of internal rotations and (b) interdependence of short-range intramolecular interactions. All the results indicate that 〈γ2〉 is practically insensitive to the excluded-volume effect. Concomitantly the behavior of 〈R2〉 has been analyzed.  相似文献   
1000.
N-isopropylacrylamide (NIPA) homopolymers having carboxylic acid-end groups were synthesized by using mercaptoacetic acid (MAA) as the chain transfer agent. Polymerization was achieved in ethanol using azobisisobutyronitrile (AIBN) as the initiator. Average molecular weight of the homopolymer estimated by titration was 1958. This carboxylic acid-ended poly(NIPA) was then copolymerized with polyethylenimine (PEI, M(W)-2000) using a water soluble carbodiimide (EDAC). With respect to carboxyl-ended poly(NIPA), the block copolymers exhibited a pH dependent-temperature sensitivity and higher LCST values in acidic pH. Scanning tunneling microscopy (STM) images of both the homopolymer and the copolymer were obtained at 25 and 45 degrees C with tip-sample bias voltages of up to 800 mV and tunneling currents approximately 1 nA. These images showed that STM can be used to visualize both the formation of copolymer chains and their structure, and also their stimuli-responsive behavior.  相似文献   
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