To solve the problem of a supplier＇s failure to deliver thus impacting supply chain system performance in the supply chain operating process, a model of supplier selection and order splitting in the context of a mult...To solve the problem of a supplier＇s failure to deliver thus impacting supply chain system performance in the supply chain operating process, a model of supplier selection and order splitting in the context of a multiple sourcing setting is proposed. First, by the analysis of the elements of expected total costs of the buyer firm, namely, expected loss costs, resilience effort costs, supplier maintenance costs, and cycle purchase costs, the expected total costs function is obtained. And then, the effects of supplier characters on the supplier selection and order splitting decisionmaking are investigated by numerical examples. The results show that the maximum delivery capacity, the probability of failure to deliver and the resilience parameters are crucial elements in determining which suppliers should be selected and how to do order splitting between suppliers. Finally, current analyses focus only on the expected total costs of the buyer firm but ignore the suppliers＇ costs： thus, it is more interesting to examine the supplier decisions from both parties＇ points of view.展开更多
The high order compact d if ference method is developed for solving the perturbation equations based on Navi er Stokes equations, and is used in studying complex evolution processes from w all negative pulse to the ...The high order compact d if ference method is developed for solving the perturbation equations based on Navi er Stokes equations, and is used in studying complex evolution processes from w all negative pulse to the turbulent coherent structure in the channel flow. Th is method contains three dimensional coupling difference scheme with high accur acy and high resolution, and the high order time splitting methods. Compared with the general spectral method, the method can be used to research turbule nt coherent structure under more general boundary conditions and in flow domains . In this paper, the generation and evolution of the turbulent coherent structur es ind uced by wall pulse in the channel flow are simulated, and the basic characterist ics and rules of the turbulent coherent structure are shown. Computational r esults indicate that a wall negative pulse is more convenient than the resonant three wave model.展开更多
The k-th(k=3,4,5)order backward differential formula(BDFk)is applied to de-velop the high order energy stable schemes for the molecular beam epitaxial model with slope selection.The numerical schemes are established b...The k-th(k=3,4,5)order backward differential formula(BDFk)is applied to de-velop the high order energy stable schemes for the molecular beam epitaxial model with slope selection.The numerical schemes are established by combining the convex splitting technique with the k-th order accurate Douglas-Dupont stabilization term in the form of Sτ^(k−1)Δ_(h)(Ф^(n)−Ф^(n−1)).With the help of the new constructed discrete gradient structure of the k-th order explicit extrapolation formula,the stabilized BDFk scheme is proved to pre-serve energy dissipation law at the discrete levels and unconditionally stable in the energy norm.By using the discrete orthogonal convolution kernels and the associated convolution embedding inequalities,the L^(2) norm error estimate is established under a weak constraint of time-step size.Numerical simulations are presented to demonstrate the accuracy and efficiency of the proposed numerical schemes.展开更多
基金The National Key Technology R& D Program of Chinaduring the 11th Five-Year Plan Period (No.2006BAH02A06)the NationalNatural Science Foundation of China(No.70671021).
文摘To solve the problem of a supplier＇s failure to deliver thus impacting supply chain system performance in the supply chain operating process, a model of supplier selection and order splitting in the context of a multiple sourcing setting is proposed. First, by the analysis of the elements of expected total costs of the buyer firm, namely, expected loss costs, resilience effort costs, supplier maintenance costs, and cycle purchase costs, the expected total costs function is obtained. And then, the effects of supplier characters on the supplier selection and order splitting decisionmaking are investigated by numerical examples. The results show that the maximum delivery capacity, the probability of failure to deliver and the resilience parameters are crucial elements in determining which suppliers should be selected and how to do order splitting between suppliers. Finally, current analyses focus only on the expected total costs of the buyer firm but ignore the suppliers＇ costs： thus, it is more interesting to examine the supplier decisions from both parties＇ points of view.
文摘The high order compact d if ference method is developed for solving the perturbation equations based on Navi er Stokes equations, and is used in studying complex evolution processes from w all negative pulse to the turbulent coherent structure in the channel flow. Th is method contains three dimensional coupling difference scheme with high accur acy and high resolution, and the high order time splitting methods. Compared with the general spectral method, the method can be used to research turbule nt coherent structure under more general boundary conditions and in flow domains . In this paper, the generation and evolution of the turbulent coherent structur es ind uced by wall pulse in the channel flow are simulated, and the basic characterist ics and rules of the turbulent coherent structure are shown. Computational r esults indicate that a wall negative pulse is more convenient than the resonant three wave model.
文摘The k-th(k=3,4,5)order backward differential formula(BDFk)is applied to de-velop the high order energy stable schemes for the molecular beam epitaxial model with slope selection.The numerical schemes are established by combining the convex splitting technique with the k-th order accurate Douglas-Dupont stabilization term in the form of Sτ^(k−1)Δ_(h)(Ф^(n)−Ф^(n−1)).With the help of the new constructed discrete gradient structure of the k-th order explicit extrapolation formula,the stabilized BDFk scheme is proved to pre-serve energy dissipation law at the discrete levels and unconditionally stable in the energy norm.By using the discrete orthogonal convolution kernels and the associated convolution embedding inequalities,the L^(2) norm error estimate is established under a weak constraint of time-step size.Numerical simulations are presented to demonstrate the accuracy and efficiency of the proposed numerical schemes.
