This paper presents an mixedinteger nonlinear programming formulation for the lane reservation problem with time-dependent travel times. It aims to design time-guaranteed paths for some transportation tasks via lane ...
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This paper presents an mixedinteger nonlinear programming formulation for the lane reservation problem with time-dependent travel times. It aims to design time-guaranteed paths for some transportation tasks via lane reservation strategy, which is to optimally select and reserve some lanes for the use of the tasks with the objective of minimizing the total traffic impact caused by the reserved lanes. The considered problem is NP-hard. The original nonlinear model is transformed into an mixedinteger linear program and a cut-and-solve based algorithm is proposed to obtain optimal solutions. Experimental tests on randomly generated instances show that the overall performance of the proposed algorithm outperforms a direct use of an optimization solver of CPLEX.
This paper studies the single machine family scheduling problem in which the goal is to minimize total tardiness. We analyze two alternative mixed-integerprogramming (MIP) formulations with respect to the time requir...
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This paper studies the single machine family scheduling problem in which the goal is to minimize total tardiness. We analyze two alternative mixed-integerprogramming (MIP) formulations with respect to the time required to solve the problem using a state-of-the-art commercial MIP solver. The two formulations differ in the number of binary variables: the first formulation has O ( n 2) binary variables whereas the second formulation has O ( n 3) binary variables, where n denotes the number of jobs to be scheduled. Our findings indicate that despite the significant higher number of binary variables, the second formulation leads to significantly shorter solution times for problem instances of moderate size.
Startup procedures of processing systems are determined by the interaction of both discrete and continuous inputs with the continuous process dynamics. This contribution introduces a modelling approach which represent...
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Startup procedures of processing systems are determined by the interaction of both discrete and continuous inputs with the continuous process dynamics. This contribution introduces a modelling approach which represents the startup dynamics as a hybrid automaton first. The task of computing optimal start up trajectories for the automaton is rewritten into a mixed integer programming problem that can be solved efficiently by branch-and-bound techniques. Furthermore, the paper describes a moving horizon approach to overcome the problem of the exponentially increasing computational effort for an increasing optimization horizon.
We consider the stochastic economic lot sizing problem with remanufacturing under customer service level constraints. The problem is a stochastic extension of the classical lot sizing problem where demand can be met v...
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We consider the stochastic economic lot sizing problem with remanufacturing under customer service level constraints. The problem is a stochastic extension of the classical lot sizing problem where demand can be met via two alternative sources: manufacturing new products and remanufacturing returned products. It is known that even the deterministic version of this problem is NP-hard. We propose a mixed integer programming based heuristic for the problem building on a static-dynamic uncertainty strategy.
In operational control of hybrid systems, control objectives often change with current operating conditions and switching among a number of control strategies is then inevitable. The proposed softly switched hybrid pr...
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In operational control of hybrid systems, control objectives often change with current operating conditions and switching among a number of control strategies is then inevitable. The proposed softly switched hybrid predictive control utilizes mixed integer programming techniques and achieves better switching transient performance both in system output/state and control input than the traditional hard switching method. Stability of the designed soft switching process is analysed and sufficient stabilization conditions are derived. Numerical examples with simulation results show that the proposed approach can be useful in practical applications.
The paper concerns a class of supply chain management problems called Joint Transportation-and-Inventory Problems (JTIPs). These problems are characterized by the presence of both transportation and inventory consider...
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The paper concerns a class of supply chain management problems called Joint Transportation-and-Inventory Problems (JTIPs). These problems are characterized by the presence of both transportation and inventory considerations, either as policy-variables or constraints. The research presented in this paper aims at determining an optimal joint inventory/transportation policy. Mathematical modeling is applied to find the optimal solution to JTIPs thus defined. The set partitioning formulation for solving the vehicle routing problem is incorporated into a discrete time, finite-horizon inventory planning problem. Two models will be discussed: time-discretized integerprogramming and the new approach with predefined quantities of delivery. As is shown in this paper, the approach allows us to use a column generation technique.
Abstract A networked control system (NCS) is a control system in which plants, sensors, controllers, and actuators are connected through communication networks. In this paper, as one of the design problems for NCSs, w...
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Abstract A networked control system (NCS) is a control system in which plants, sensors, controllers, and actuators are connected through communication networks. In this paper, as one of the design problems for NCSs, we consider optimal sampled-data control of linear systems with uncertain input delay and uncertain sampling period. First, an input delay system is transformed into a discrete-time system with parameter uncertainty. Furthermore, the obtained system is expressed as a mixed logical dynamical model by using our previously proposed modeling method. Next, a given continuous-time cost function is transformed into a discrete-time cost function with parameter uncertainty, and the optimal control problem is approximately expressed as a mixed integer programming problem.
One of the most important goals of disaster management teams is to protect the assets and infrastructures of the community in the event of accidents such as wildfires and floods. This issue requires appropriate operat...
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One of the most important goals of disaster management teams is to protect the assets and infrastructures of the community in the event of accidents such as wildfires and floods. This issue requires appropriate operations of all disaster management teams and analysis of available information for suitable decision making and consequently timely response. A mixedinteger mathematical model is presented and solved for allocating resources to different districts to protect more assets in an available time. The proposed model tries to protect more valuable assets in pre-determined districts with optimized team allocation strategy. Finally, for validating the model, a numerical example is solved with an exact method and the results of various sensitivity analyses have been reported. The computational results indicate the efficiency and applicability of the proposed model in real conditions comparing to existing classic models.
In modern giant buildings,in order to improve energy utilization efficiency, cooling systems have developed from conventional chillers alone to smart energy net which includes chillers,ice storage,ground-source heat p...
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In modern giant buildings,in order to improve energy utilization efficiency, cooling systems have developed from conventional chillers alone to smart energy net which includes chillers,ice storage,ground-source heat pump,combined cooling heating and power( CCHP) and so on. The reasonable distribution of load is the key to guarantee such system in economical *** on typical multi-type cooling system,economic models of different devices are presented and real-time intelligent economic scheduling with the approach of mixed integer programming is carried out. This algorithm has been applied in a certain building of Shanghai and results of simulation show that it is able to provide guidance on intelligent economic scheduling for multi-type cooling system.
As environmental problems such as global warming has become increasingly prevalent, and with the rise in foreign dependence on fossil fuels, energy efficiency and energy saving programs and research have risen. This g...
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As environmental problems such as global warming has become increasingly prevalent, and with the rise in foreign dependence on fossil fuels, energy efficiency and energy saving programs and research have risen. This global focus on energy efficiency has accelerated studies on this subject in order to decrease foreign dependency on fossil fuels, to protect the environment, to minimize the effect of energy costs to national economies, and to assure the energy supply. With increasing population and fast economic development, energy consumption in Turkey has increased significantly. Therefore, current policies need to be updated and additional measures need to be implemented. The Energy Efficiency Strategy document states that Turkey aims to decrease its energy intensity by 20% by 2023, and accordingly new policies and strategies are being carried out in every sector to achieve this result. The uninterrupted, cost-effective, and globally sustainable energy supply is at the heart of national energy policies globally. The Energy Efficiency Obligation Scheme (EEOS) is among the fundamental tools created to increase energy efficiency in the European Union (EU). Many EU countries have successfully implemented EEOS, and further white certificate markets as a central tool for increasing energy efficiency. For example, Italy has seen particularly positive achievements with a white certificate market by avoiding consumption of 6.7 million tons of oil equivalent (TOE). The implementation of National Energy Efficiency Action Plan (NEEAP) in terms of energy saving was a great step in Turkey. In this document, EEOS has been analyzed in detail. All of these studies are expected to shed light on the energy efficiency liability system to be implemented in Turkey in the future. For this purpose, it is thought that the inclusion of energy service companies into these models will have a positive effect on the success of the system. Within the scope of this study, it has been concluded tha
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