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91.
This paper investigates the impact of a secondary market, where retailers can buy and sell excessinventories, on the supply chain. We develop a two-period model with a single manufacturer and tworetailers. At the beginning of the first period the retailers order and receive products from themanufacturer, but at the beginning of the second period, they can trade surplus products betweenthemselves in the secondary market. We investigate the impact of the correlated dependence ofretailers' demand on both the quantity effect and the allocation effect under the secondary market.Lastly,we study potential strategies for the manufacturer to increase sales with the existence of thesecondary market.  相似文献   
92.
LOGISTICS SCHEDULING: ANALYSIS OFTWO-STAGE PROBLEMS   总被引:4,自引:0,他引:4  
This paper studies the coordination effects between stages for scheduling problems where decision-making is a two-stage process. Two stages are considered as one system. The system can be a supply chain that links two stages, one stage representing a manufacturer; and the other, a distributor It also can represent a single manufacturer, while each stage represents a different department responsible for a part of operations. A problem that jointly considers both stages in order to achieve ideal overall system performance is defined as a system problem. In practice, at times, it might not be feasible for the two stages to make coordinated decisions due to (i) the lack of channels that allow decision makers at the two stages to cooperate, and/or (ii) the optimal solution to the system problem is too difficult (or costly) to achieve.Two practical approaches are applied to solve a variant of two-stage logistic scheduling problems. The Forward Approach is defined as a solution procedure by which the first sta  相似文献   
93.
Aiming at technical difficulties in feature extraction for the inverse synthetic aperture radar (ISAR) target recognition, this paper imports the concept of visual perception and presents a novel method, which is based on the combination of non-negative sparse coding (NNSC) and linear discrimination optimization, to recognize targets in ISAR images. This method implements NNSC on the matrix constituted by the intensities of pixels in ISAR images for training, to obtain non-negative sparse bases which characterize sparse distribution of strong scattering centers. Then this paper chooses sparse bases via optimization criteria and calculates the corresponding non-negative sparse codes of both training and test images as the feature vectors, which are input into k neighbors classifier to realize recognition finally. The feasibility and robustness of the proposed method are proved by comparing with the template matching, principle component analysis (PCA) and non-negative matrix factorization (NMF) via simulations.  相似文献   
94.
An algorithm is given for computing in a very efficient way the topology of two real algebraic plane curves defined implicitly.The authors preform a symbolic pre-processing that allows us later to execute all numerical computations in an accurate way.  相似文献   
95.
This paper develops the large sample properties of the solutions of the general estimating equations which are unbiased or asymptotically unbiased or with nuisance parameters for correlated data.The authors do not make the assumption that the estimating equations come from some objective function when we establish the large sample properties of the solutions.So these results extend the work of Newey and McFadden(1994) and are more widely applicable.Furthermore,we provide some examples to justify the importance of our work.  相似文献   
96.
This paper gives a theoretical analysis for the algorithms to compute functional decomposition for multivariate polynomials based on differentiation and homogenization which were proposed by Ye,Dai,and Lam(1999) and were developed by Faugere,Perret(2006,2008,2009).The authors show that a degree proper functional decomposition for a set of randomly decomposable quartic homogenous polynomials can be computed using the algorithm with high probability.This solves a conjecture proposed by Ye,Dai,and Lam(1999).The authors also propose a conjecture which asserts that the decomposition for a set of polynomials can be computed from that of its homogenization and show that the conjecture is valid with high probability for quartic polynomials.Finally,the authors prove that the right decomposition factors for a set of polynomials can be computed from its right decomposition factor space.  相似文献   
97.
This paper considers the mixed covolume method for the second-order elliptic equations over quadrilaterals.Superconvergence results are established in this paper on quadrilateral grids satisfying the h~2-parallelogram condition when the lowest-order Raviart-Thomas space is employed in the mixed covolume method.The authors prove O(h~2) accuracy between the approximate velocity or pressure and a suitable projection of the real velocity or pressure in the L~2 norm.Numerical experiments illustrating the theoretical results are provided.  相似文献   
98.
This paper considers the nonstandard renewal risk model in which a part of surplus is invested into a Black-Scholes market whose price process is modelled by a geometric Brownian motion, claim sizes form a sequence of not necessarily identically distributed and pairwise quasi-asymptotically independent random variables with dominatedly-varying tails.The authors obtain a weakly asymptotic formula for the finite-time and infinite-time ruin probabilities.In particular,if the claims are identically distributed and consistently-varying tailed,then an asymptotic formula is presented.  相似文献   
99.
This paper studies variational discretization for the optimal control problem governed by parabolic equations with control constraints.First of all,the authors derive a priori error estimates where |||u-U(h|||L∞(J;L2(Ω))=O(h2+k).It is much better than a priori error estimates of standard finite element and backward Euler method where |||μ-Uh|||(L∞(J;L2(Ω))=O(h+ k).Secondly,the authors obtain a posteriori error estimates of residual type.Finally,the authors present some numerical algorithms for the optimal control problem and do some numerical experiments to illustrate their theoretical results.  相似文献   
100.
本文以导弹侵彻子母弹抛撒为背景,提出了一种适合于有限子弹抛撒的均匀性指标,并且运用现代统计方法——BayesBootstrap法模拟了均匀性指标统计量的分布;另外,从火力运用的观点出发,根据子母弹抛撒的均匀性指标的大小对战斗部毁伤效率的影响,确定了均匀性指标的容许下限;应用统计检验方法给出了子母弹抛撒的均匀性的评定方法,为导弹侵彻子母弹抛撒的鉴定及同类武器该项目的鉴定提供可信且便于操作的方法。  相似文献   
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