In MPLS (Multi-Protocol Label Switching) over optical networks, both the optical level and the MPLS level fault recovery can be considered. Generally, a more flexible path arrangement can be realized by the MPLS level...
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In MPLS (Multi-Protocol Label Switching) over optical networks, both the optical level and the MPLS level fault recovery can be considered. Generally, a more flexible path arrangement can be realized by the MPLS level recovery, while fast recovery can be achieved by the optical level recovery. When the optical level recovery is adopted, only normal traffic is carried through the working lightpaths and only recovered traffic is carried through the backup lightpaths. In contrast, the working LSPs (Label-Switched Paths) and the backup LSPs corresponding to other working LSPs can be accommodated into an identical lightpath when the MPLS level recovery is adopted. By such sophisticated accommodation of LSPs into the lightpaths, lightpath bandwidth can be utilized efficiently under the condition that the bandwidth utilization is restricted to attain the given objective of transfer quality for the MPLS packets in the normal state and unrestricted in a short time a failure occurs somewhere in the network. This paper proposes a simple mathematical programming model to obtain the optimum arrangement of the working and backup LSPs assuming the MPLS level recovery and a practical LSPs provisioning mode. By comparing the minimized network cost obtained from the optimum arrangement of the working and backup LSPs with the network cost resulting from the optical level recovery, this paper quantitatively evaluates the effectiveness of such bandwidth utilization improvement obtained from the MPLS level recovery and reveals that the MPLS level recovery can actually reduce the network cost due to its flexible arrangement of LSPs on the lightpaths.
The demands for fresh process waters and heating/cooling utilities arise intermittently in batch plants. Due to equipment constraints, the quality and flow-rate of each resulting wastewater stream are required to be c...
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The demands for fresh process waters and heating/cooling utilities arise intermittently in batch plants. Due to equipment constraints, the quality and flow-rate of each resulting wastewater stream are required to be controlled within specified limits before treatment/regeneration. In this paper, a general mathematical programming model is developed to design the optimal buffer system for equalizing the flow-rates and contaminant concentrations of its outputs. Three examples are provided to illustrate the effectiveness of proposed approach. (c) 2005 Elsevier Ltd. All rights reserved.
In this letter, we propose a global model to solve the expansion problem of universal mobile telecommunications system (UMTS) networks. Since the network expansion problem is a generalization of the network design pro...
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In this letter, we propose a global model to solve the expansion problem of universal mobile telecommunications system (UMTS) networks. Since the network expansion problem is a generalization of the network design problem, the proposed model can be used for the design of UMTS networks. The proposed model deals simultaneously with the cell, the access network and the core network planning subproblems. This global approach has the advantage of providing better results since, in general, optimal solutions to all subproblems do not provide an optimal solution to the global problem. Moreover, this model fits real life situations in which mobile users have the choice to subscribe or to leave a service providers. Numerical results are presented and analyzed.
The optical network represents a promising approach to achieve a scalable backbone network. In backbone networks, survivability is important because high volumes of traffic are prone to be damaged by faulty equipment....
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The optical network represents a promising approach to achieve a scalable backbone network. In backbone networks, survivability is important because high volumes of traffic are prone to be damaged by faulty equipment. Various design methods for survivable optical networks have been proposed, although none considering the simultaneous maintenance of multiple transmission lines has been proposed to our knowledge. This paper proposes a design method for survivable optical networks where multiple transmission lines sharing common transmission equipment may suffer simultaneous damage, due to failure in the transmission equipment. Moreover, two transmission lines can be maintained simultaneously. A mathematical programming model to obtain the optimum light-path arrangement is presented assuming three kinds of lightpath recovery schemes. The relation between the required transmission line capacity and the combination pattern of two transmission lines that undergo maintenance is clarified using the proposed design method.
作者：
Li, DFDalian Naval Acad
Dept 2 Dalian 116018 Liaoning Peoples R China Univ Manchester
Inst Sci & Technol Manchester Sch Management Manchester M60 1QD Lancs England
It seems that there is little investigation on fuzzy multiattribute decision making (FMADM) problems under uncertainty, which are of important to scientific researches and real life applications. FMADM problems under ...
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It seems that there is little investigation on fuzzy multiattribute decision making (FMADM) problems under uncertainty, which are of important to scientific researches and real life applications. FMADM problems under uncertainty are investigated in this paper. Novel mathematical programming models are constructed for FMADM problems under uncertainty, and corresponding solving methods are proposed. The approach proposed in this paper may reflect both subjective judgment and objective information. Moreover, pairwise chain comparison methods for determination of relative membership degrees and weights are also proposed. Feasibility and effectiveness of the models and approach proposed in this paper are illustrated with a numerical example. (C) 2004 Elsevier Inc. All rights reserved.
In recent years, to construct the recycle-based society that aimed at utilizing effectively waste as resources among different industries has become an urgent need in order to reduce the quantity of whole solid waste....
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ISBN:
(纸本)1880653648
In recent years, to construct the recycle-based society that aimed at utilizing effectively waste as resources among different industries has become an urgent need in order to reduce the quantity of whole solid waste. For the realization of the recycle-based society, it is indispensable to build a new physical distribution system. In this paper, a concept of physical distribution system that makes use of advantages of ship transportation so as to support the recycle-based society is proposed. And as a practical example of applying the proposal concept, the industrial waste transportation by shipping is evaluated through the calculation of CO(2) emissions by conducting mathematical programming model.
This paper presents a more general mathematical programming model to solve a lot streaming problem in multistage batch production systems in which transportation activities are involved. The purpose of the proposed ma...
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This paper presents a more general mathematical programming model to solve a lot streaming problem in multistage batch production systems in which transportation activities are involved. The purpose of the proposed mathematical programming model is to find the optimal start time, the optimal number of transfer batches, and the optimal allocation of variable transfer batches that minimize the total cost, including the makespan cost and the transportation cost. Two efficient heuristic procedures are developed due to the large amount of computational time required to solve the proposed mathematical programming model. A practical application of the two proposed heuristic methods is demonstrated to show their real-world usefulness. We also recommend the best appropriate heuristic method that can be chosen by a production manager under a certain premise. An experiment consisting of two phases was conducted to further verify the excellent performance of the two proposed heuristic methods. (C) 2003 Elsevier Ltd. All rights reserved.
The collaborative integration with global third party logistics (3PL) to execute physical distribution dictates the success of any global supply chain (GSC) application. In an overall effort to minimize the system-wid...
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The collaborative integration with global third party logistics (3PL) to execute physical distribution dictates the success of any global supply chain (GSC) application. In an overall effort to minimize the system-wide cost, global 3PL can apply various consolidation policies to maximize the utilization of expensive transportation such as aircraft. Freight consolidation has received considerable attention in recent years, but the application of consolidation policies by integrated global 3PL under an e-business model is rarely discussed. The emergence of mass customization has challenged integrated logistics providers to adjust their consolidation policies in order to simultaneously minimize the cost and fulfill the service commitments. This paper examines a special class of freight consolidation at an integrated global logistics company in GSC. A mathematical programming model has been developed to assist the evaluation of consolidation policies. The computational results reveal a substantial cost saving and a service level improvement of about 20% as a consequence of implementing a collaborative consolidation policy. (C) 2002 Published by Elsevier Science Ltd.
A quadratic programmingmodel is established to choose the blocks to be blasted in a given period. The length of this period depends on the production planning requirements. During the given period, the blocks' pa...
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A quadratic programmingmodel is established to choose the blocks to be blasted in a given period. The length of this period depends on the production planning requirements. During the given period, the blocks' parameters are available from the geological database of the mine. The objective is to minimize the deviation of the average ore grade of blasted blocks from the standard ore grade required by the mill. Transportation ability constraint. production quantity demand constraint. minimum safety bench constraint. block size constraint and block, bench precedence constraints are considered in forming the programmingmodel. This model has more practical objective function and reasonable constraints compared with the existing model for this kind of problems.
The paper presents a modeling framework to analyze some important issues associated with operation planning of a power system. Major activities involved in operations planning of large integrated power systems are con...
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