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On Transshipment Games with Identical Newsvendors  [PDF]
Behzad Hezarkhani,Wieslaw Kubiak,Bruce Hartman
Mathematics , 2013,
Abstract: In a transshipment game, supply chain agents cooperate to transship surplus products. This note studies the effect of size of transshipment coalitions on the optimal production/order quantities. It characterizes these quantities for transshipment games with identical newsvendors and normally distributed market demands. It also gives a closed form formula for equal allocation in their cores.
A biologically inspired model for transshipment problem  [PDF]
Cai Gao,Chao Yan,Daijun Wei,Yong Hu,Sankaran Mahadevan,Yong Deng
Mathematics , 2014,
Abstract: Transshipment problem is one of the basic operational research problems. In this paper, our first work is to develop a biologically inspired mathematical model for a dynamical system, which is first used to solve minimum cost flow problem. It has lower computational complexity than Physarum Solver. Second, we apply the proposed model to solve the traditional transshipment problem. Compared with the conditional methods, experiment results show the provided model is simple, effective as well as handling problem in a continuous manner.
Evolutionary multiobjective optimization of the multi-location transshipment problem  [PDF]
Nabil Belgasmi,Lamjed Ben Said,Khaled Ghédira
Mathematics , 2011, DOI: 10.1007/s12351-008-0015-5
Abstract: We consider a multi-location inventory system where inventory choices at each location are centrally coordinated. Lateral transshipments are allowed as recourse actions within the same echelon in the inventory system to reduce costs and improve service level. However, this transshipment process usually causes undesirable lead times. In this paper, we propose a multiobjective model of the multi-location transshipment problem which addresses optimizing three conflicting objectives: (1) minimizing the aggregate expected cost, (2) maximizing the expected fill rate, and (3) minimizing the expected transshipment lead times. We apply an evolutionary multiobjective optimization approach using the strength Pareto evolutionary algorithm (SPEA2), to approximate the optimal Pareto front. Simulation with a wide choice of model parameters shows the different trades-off between the conflicting objectives.
Efficient Heuristic Based Methods for Two-Stage Transshipment Problem  [PDF]
Priyank Sinha, Renduchintala Raghavendra Kumar Sharma
American Journal of Operations Research (AJOR) , 2018, DOI: 10.4236/ajor.2018.84016
Abstract: In this article, we propose efficient methods for solving two stage transshipment problems. Transshipment problem is the special case of Minimum cost flow problem in which arc capacities are infinite. We start by proposing a novel problem formulation for a two stage transshipment problem. Later, special structure of our problem formulation is utilized to devise two dual based heuristics solutions with computational complexity of O (n2), and O (n3) respectively. These methods are motivated by the methods developed by Sharma and Saxena [1], Sinha and Sharma [2]. Our methods differ in the initialization and the subsequent variation of the dual variables associated with the transshipment nodes along the shortest path. Lastly, a method is proposed to extract a very good primal solution from the given dual solutions with a computational complexity of O (n2). Efficacy of these methods is demonstrated by our numerical analysis on 200 random problems.
Optimal Layout of Transshipment Facilities on An Infinite Homogeneous Plane  [PDF]
Weijun Xie,Yanfeng Ouyang
Mathematics , 2014,
Abstract: This paper studies optimal spatial layout of transshipment facilities and the corresponding service regions on an infinite homogeneous plane $\mathbb{R}^2$ that minimize the total cost for facility set-up, outbound delivery and inbound replenishment transportation. The problem has strong implications in the context of freight logistics and transit system design. This paper first focuses on a Euclidean plane and presents a new proof for the known Gersho's conjecture, which states that the optimal shape of each service region should be a regular hexagon if the inbound transportation cost is ignored. When inbound transportation cost becomes non-negligible, however, we show that a tight upper bound can be achieved by a type of elongated cyclic hexagons, while a cost lower bound based on relaxation and idealization is also obtained. The gap between the analytical upper and lower bounds is within 0.3%. This paper then shows that a similar elongated non-cyclic hexagon shape is actually optimal for service regions on a rectilinear metric plane. Numerical experiments and sensitivity analyses are conducted to verify the analytical findings and to draw managerial insights.
Influence of Lateral Transshipment Policy on Supply Chain Performance: A Stochastic Demand Case  [PDF]
Jingxian Chen, Jianxin Lu
iBusiness (IB) , 2010, DOI: 10.4236/ib.2010.21009
Abstract: Considering the supply chain consists of one supplier and two retailers, we construct the system’s dynamic models which face stochastic demand in the case of non-lateral transshipment (NLT), unidirectional lateral transshipment (ULT) and bidirectional lateral transshipment (BLT). Numerical example simulation experiments of these models were run on Venple. We adopt customer demand satisfaction rate and total inventory as performance indicators of supply chain. Through the comparative of the simulation results with the NLT policy, we analyze the influence of ULT policy and BLT policy on system performance. It shows that, if retailers face the same random distribution demand, lateral transshipment policy can effectively improve the performance of supply chain system; if the retailers face different random distribution demand, lateral transshipment policy cannot effectively improve the performance of supply chain systems, even reduce system’s customer demand satisfaction rate, and increase system inventory variation.
The effective potential and transshipment in thermodynamic formalism at temperature zero  [PDF]
Artur O. Lopes,Eduardo Garibaldi
Mathematics , 2010,
Abstract: Denote the points in {1,2,..,r}^{Z}= {1,2,..,r}^{N} x {1,2,..,r}^{N} by ({y}^*, {x}). Given a Lipschitz continuous observable A: {1,2,..,r}^{Z} \to {R} , we define the map {G}^+: {H}\to {H} by {G}^+(\phi)({y}^*) = \sup_{\mu \in {M}_\sigma} [\int_{\{1,2,..,r\}^{N}} ( A({y}^*, {x}) + \phi({x})) d\mu({x}) + h_\mu(\sigma) ], where: \sigma is the left shift map acting on {1,2,..,r}^{N}; {M}_\sigma denotes the set of \sigma-invariant Borel probabilities; h_\mu(\sigma) indicates the Kolmogorov-Sinai entropy; {H } is the Banach space of Lipschitz real-valued functions on {1,2,..,r}^{N}. We show there exist a unique \phi^+ \in {H } and a unique \lambda^+\in {R} such that {G}^+ (\phi^+) = \phi^+ + \lambda^+. We say that \phi^+ is the effective potential associated to A. This also defines a family of $\sigma$-invariant Borel probabilities \mu_{{y}^*} on {1,2,..,r}^{N}, indexed by the points {y}^* \in {1,2,..,r}^{N}. Finally, for A fixed and for variable positive real values \beta, we consider the same problem for the Lipschitz observable \beta A. We investigate then the asymptotic limit when \beta\to \infty of the effective potential (which depends now on \beta) as well as the above family of probabilities. We relate the limit objects with an ergodic version of Kantorovich transshipment problem. In statistical mechanics \beta \propto 1/T, where T is the absolute temperature. In this way, we are also analyzing the problem related to the effective potential at temperature zero.
联合国WFP援华项目管理模式与启示  [PDF]
帅传敏,孔祥智,廖其胜
科技进步与对策 , 2006,
Abstract: 通过对全国18个省市自治区31个WFP粮援项目的实地调查,阐述了联合国世界粮食计划署(WFP)援华项目的主要特点,并从组织管理、计划管理、工程管理、援粮管理、科学决策以及评价与控制6个方面系统分析了WFP援华项目独特的项目管理模式。最后,指出了WFP粮援项目管理模式对于我国新一轮扶贫开发和我国农业项目管理的重要启示和借鉴意义。联合国WFP以工代赈项目管理模式启示与借鉴
Total factor productivity effects of interregional knowledge spillovers
Thomas Scherngell,Manfred M. Fischer,Martin Reismann
Romanian Journal of Regional Science , 2007,
Abstract: The objective of this study is to identify knowledge spillovers that spread acrossregions in Europe and vary in magnitude for different industries. The study uses a panel of203 NUTS-2 regions covering the 15 pre-2004 EU-member-states to estimate the impactover the period 1998-2003, and distinguish between five major industries. The studyimplements a fixed effects panel data regression model with spatial autocorrelation toestimate effects using patent applications as a measure of R&D output to capture thecontribution of R&D (direct and spilled-over) to regional productivity at the industry level.The results suggest that interregional knowledge spillovers and their productivity effects areto a substantial degree geographically localised and this finding is consistent with thelocalisation hypothesis of knowledge spillovers. There is a substantial amount ofheterogeneity across industries with evidence that two industries (electronics, and chemicalindustries) produce interregional knowledge spillovers that have positive and highlysignificant productivity effects. The study, moreover, confirms the importance of spatialautoregressive disturbance in the fixed effects model for measuring the TFP impact ofinterregional knowledge spillovers at the industry level.
Some Aspects of Ukraine Competitiveness Improvement in the Black Sea Region Transshipment Market  [PDF]
L. Tertychnaya,M. Voloschuk
Economics of Development , 2011,
Abstract: It has been researched that Ukraine as a maritime state cannot stay aside the processes that take place in the overseas transport market, especially containerization and the growth of transshipment share in this market. The Ukrainian legislation improvement was required by the competitiveness intensification in the Black Sea Region market. As a result the Law " About Changes of Some Legislative Acts of Ukraine concerning the Transit Freights Customs Official Registration Simplification" was adopted on 1st June, 2010. These changes in current legislation allow to shorten the term and to reduce the cost of Customs Official Registration. However, there are still serious obstacles for the Ukrainian ports competitiveness in the transshipment market.Conditions, leading to the transshipment extension in the ports have been defined. These are the existence of necessary capacity market near the prospective hub; the hub geographical proximity to the ports that will be served by the feeders; the capacity and call cost.It has been emphasized that Rumanian Konstanza is still leading and is a monopolist in the region at the moment. However, the positive dynamics of container terminals production facilities development in such ports as Illichevsk, Odessa and Yuzhnyi and more advantageous geographical location allow to predict the forthcoming changes in the transshipment market for benefit of Ukraine. Today only uncompetitive service prices of Ukrainian ports and their fixing out-of-date mechanism are the obstacles for transit containers flows in Ukrainian staging posts. Thereby, the competitive advantages in this perspective for Ukraine sphere should be gained further.
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