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Qiang Meng - One of the best experts on this subject based on the ideXlab platform.

  • regional multimodal logistics network design considering Demand uncertainty and co2 emission reduction target a system optimization approach
    Journal of Cleaner Production, 2020
    Co-Authors: Qiang Meng, Jiehui Jiang, Dezhi Zhang, Yajie Liu
    Abstract:

    Abstract This paper investigates an interesting regional multimodal logistics network design problem with CO2 emission reduction target and uncertain Demands in the context of urban cluster development. From the perspective of system optimization, a regional logistics network involves a centralized logistics authority and a centralized carrier, where the logistics authority concerns the regional logistics network configuration in terms of the number, location and scale of logistics parks and the subsidies of rail transportation links, and the carrier’s decisions include the choice of transportation route for each logistics Demand. Given a determined logistics Demand Pattern, this multi-stakeholder decision making problem is first formulated as a bi-level programming model followed by its equivalent mathematical programming with equilibrium constraints (MPEC) to depict the leader-follower behaviors. To capture the risk aversion level of the logistics authority in uncertain Demand environment, an improved adjustable robust optimization method is proposed, including an individual control parameter and providing an exact expression of the maximum satisfaction probability. Computational results and related impact analysis demonstrate that the proposed models and solution methods are effective, which can provide the beneficial theory basis and practice guide for the green and sustainable development of regional logistics.

  • liner container seasonal shipping revenue management
    Transportation Research Part B-methodological, 2015
    Co-Authors: Yadong Wang, Qiang Meng
    Abstract:

    This paper proposes a liner container seasonal shipping revenue management problem for a container shipping company. For a given weekly multi-type shipment Demand Pattern in a particular season, the proposed problem aims to maximize the total seasonal shipping profit by determining the number of multi-type containers to be transported and assigned on each container route, the number of containerships deployed on each ship route, and the sailing speed of containerships on each shipping leg subject to both the volume and capacity constraints of each containership. By adopting the realistic bunker consumption rate of a containership as a function of its sailing speed and payload (displacement), we develop a mixed-integer nonlinear programing with a nonconvex objective function for the proposed liner container seasonal shipping revenue management problem. A tailored branch and bound (B&B) method is designed to obtain the global e-optimal solution of the model. Numerical experiments are finally conducted to assess the efficiency of the solution algorithm and to show the applicability of the developed model.

  • liner ship route capacity utilization estimation with a bounded polyhedral container shipment Demand Pattern
    Transportation Research Part B-methodological, 2013
    Co-Authors: Shuaian Wang, Qiang Meng, Michael G H Bell
    Abstract:

    This paper aims to estimate capacity utilization of a liner ship route with a bounded polyhedral container shipment Demand Pattern, arising in the liner container shipping industry. The proposed maximum and minimum liner ship route capacity utilization problems are formulated as a linear programming model and a min–max model, respectively. We examine two fundamental properties of the min–max model. These two nice properties enable us to develop two e-optimal global optimization algorithms for solving the min–max model, which find a globally e-optimal solution by iteratively cutting off the bounded polyhedral container shipment Demand set with a cut. The latter algorithm overcomes non-convexity of the remaining feasible Demand set generated by the former algorithm via a novel hyperplane cut. Each hyperplane cut can assure that the current vertex of the polyhedral Demand set is cut off, whereas solutions that may improve the current one by more than a factor of e are retained. Extensive numerical experiments for problems larger than those encountered in real applications demonstrate the computational efficacy of the latter algorithm.

  • modeling the capacity and level of service of urban transportation networks
    Transportation Research Part B-methodological, 2000
    Co-Authors: Hai Yang, Michael G H Bell, Qiang Meng
    Abstract:

    Abstract Consider an urban transportation network. For a given current origin–destination (O–D) Demand Pattern, we can have a corresponding link flow Pattern on the network through an appropriate equilibrium traffic assignment model. Supposing that flow on each link associated with the current O–D Demand is below a given upper bound such as link capacity or any other prescribed threshold, we would ask how much additional Demand from each trip origin can be accommodated by the network so that flow on each link is still within the given bound when the additional and existing Demand is together assigned to the network. This problem can be referred to as the network capacity and level of service problem and is fully investigated in this paper. New formulations are presented and compared with existing techniques in terms of the assumption of O–D Demand Pattern and travelers' route and location choice behavior for the capacity and level of service modeling. Numerical examples are provided and potential applications of the models are mentioned.

S Masud M Rana - One of the best experts on this subject based on the ideXlab platform.

K S Chaudhuri - One of the best experts on this subject based on the ideXlab platform.

  • an imperfect production process for time varying Demand with inflation and time value of money an emq model
    Expert Systems With Applications, 2011
    Co-Authors: Biswajit Sarkar, Shib Sankar Sana, K S Chaudhuri
    Abstract:

    Abstract The paper deals with an economic manufacturing quantity (EMQ) model for time-dependent (quadratic) Demand Pattern. Every manufacturing sector wants to produce perfect quality items. But in long run process, there may arise different types of difficulties like labor problem, machinery capabilities problems, etc., due to that the machinery systems shift from in-control state to out-of-control state as a result the manufacturing systems produce imperfect quality items. The imperfect items are reworked at a cost to become the perfect one. The rework cost may be reduced by improvements in product reliability i.e., the production process depend on time and also the reliability parameter. We want to determine the optimal product reliability and production rate that achieves the biggest total integrated profit for an imperfect manufacturing process using Euler–Lagrange theory to build up the necessary and sufficient conditions for optimality of the dynamic variables. Finally, a numerical example is discussed to test the model which is illustrated graphically also.

  • an eoq model for deteriorating items with shortages and a linear trend in Demand
    Journal of the Operational Research Society, 1991
    Co-Authors: Adrijit Goswami, K S Chaudhuri
    Abstract:

    We consider here the inventory replenishment policy over a fixed planning period for a deteriorating item having a deterministic Demand Pattern with a linear trend and shortages. The number of reorders, the interval between two successive reorders and the shortage intervals over a finite time-horizon are all determined in an optimal manner so as to keep the average system cost to a minimum. One numerical example illustrates how the procedure works. The counterpart of this example in the no-shortage case is also given. The effects of variation in the deterioration rate on the optimal policy are also indicated with numerical examples.

  • eoq model for an inventory with a linear trend in Demand and finite rate of replenishment considering shortages
    International Journal of Systems Science, 1991
    Co-Authors: Adrijit Goswami, K S Chaudhuri
    Abstract:

    An economic order quantity (EOQ) model is developed for an item with a deterministic time-dependent Demand Pattern with a linear (positive) trend. It is assumed that the inventory is replenished at a uniform rate. The model is solved allowing either no shortage or a shortage in the inventory. The procedures of applying the results in practical cases are illustrated with the help of numerical examples.

Seongjoon Byeon - One of the best experts on this subject based on the ideXlab platform.

  • energy cost optimization for water distribution networks using Demand Pattern and storage facilities
    Sustainability, 2018
    Co-Authors: Yungyu Chang, Gyewoon Choi, Juhwan Kim, Seongjoon Byeon
    Abstract:

    Energy consumption in water supply systems is closely connected with the Demand for water, since energy is mostly consumed in the process of water transport and distribution, in addition to the energy that might be needed to pump the water from its sources. Existing studies have been carried out on optimizing the pump operations to attain appropriate pressure and on controlling the water level of storage facilities to transfer the required Demand and to reduce the energy cost. The idea is to reduce the amount of the water being supplied when the unit price of energy is high and to increase the supply when the unit price is low. To realize this scheme, the energy consumption of water supply systems, the amount of water transfer, the organization of energy cost structure, the utilization of water tanks, and so forth are investigated and analyzed to establish a model of optimized water Demand management based on the application of water tanks in supplied areas. In this study, with the assumption that energy cost can be reduced by the redistribution of a Demand Pattern, a numerical analysis is conducted on transferring water Demand at storage facilities from the peak energy cost hours to the lower energy cost hours. This study was applied at the Bupyeong 2 reservoir catchment, Incheon, Korea.

Atsuo Murata - One of the best experts on this subject based on the ideXlab platform.

  • an inventory model for deteriorating items with varying Demand Pattern and unknown time horizon
    International Journal of Industrial Engineering Computations, 2011
    Co-Authors: Ibraheem Abdul, Atsuo Murata
    Abstract:

    The primary assumptions with many multi-period inventory lot-sizing models are fixed time horizon and uniform Demand variation within each period. In some real inventory situations, however, the time horizon may be unknown, uncertain or imprecise in nature and the Demand Pattern may vary within a given replenishment period. This paper presents an economic order quantity model for deteriorating items where Demand has different Pattern with unknown time horizon. The model generates optimal replenishment schedules, order quantity and costs using a general ramp-type Demand Pattern that allows three-phase variation in Demand. Shortages are allowed with full backlogging of Demand and all possible replenishment scenarios that can be encountered when shortages and Demand Pattern variation occur in multi-period inventory modeling are also considered. With the aid of numerical illustrations, the advantages of allowing for variation in Demand Pattern within replenishment periods, whenever they occur, are explored. The numerical examples show that the length of the replenishment period generated by the model varies with the changes in Demand Patterns.