In this paper we present a case study which involves the design of a supply chain network for industrial waste collection. The problem is to transport metal waste from 17 factories to containers and from containers to a disposal center (DC) at an
organized region of automobile parts suppliers. We applied the classic mixedinteger programming (MIP) model for the two-stage supply chain to the solution of this problem. The visualization of the optimal solution provided us with several
interesting insights that would not be easily discovered otherwise.
http://research.sabanciuniv.edu.
Optimizing Waste Collection In An Organized Industrial Region: A Case Studyertekg
Download Link > https://ertekprojects.com/gurdal-ertek-publications/blog/optimizing-waste-collection-in-an-organized-industrial-region-a-case-study/
In this paper we present a case study which involves the design of a supply chain network for industrial waste collection. The problem is to transport metal waste from 17 factories to containers and from containers to a disposal center (DC) at an organized region of automobile parts suppliers. We applied the classic mixed-integer programming (MIP) model for the two-stage supply chain to the solution of this problem. The visualization of the optimal solution provided us with several interesting insights that would not be easily discovered otherwise.
HOPX Crossover Operator for the Fixed Charge Logistic Model with Priority Bas...IJECEIAES
In this paper, we are interested to an important Logistic problem modelised us optimization problem. It is the fixed charge transportation problem (FCTP) where the aim is to find the optimal solution which minimizes the objective function containig two costs, variable costs proportional to the amount shipped and fixed cost regardless of the quantity transported. To solve this kind of problem, metaheuristics and evolutionary methods should be applied. Genetic algorithms (GAs) seem to be one of such hopeful approaches which is based both on probability operators (Crossover and mutation) responsible for widen the solution space. The different characteristics of those operators influence on the performance and the quality of the genetic algorithm. In order to improve the performance of the GA to solve the FCTP, we propose a new adapted crossover operator called HOPX with the priority-based encoding by hybridizing the characteristics of the two most performent operators, the Order Crossover (OX) and Positionbased crossover (PX). Numerical results are presented and discussed for several instances showing the performance of the developed approach to obtain optimal solution in reduced time in comparison to GAs with other crossover operators.
The selection of third party logistics (TPL) providers is an important issue for enterprises to
outsource their logistics business. In this paper we propose a comprehensive evaluation model for TPL
suppliers based on AHP method. Furthermore, we Base on the evaluation index system including logistics cost,
the logistics operation efficiency and the basic qualities of service. The efficiency and application of the
proposed approach has been illustrated with a case study in Emergency Department of Sfax hospital
On The Use of Transportation Techniques to Determine the Cost of Transporting...IOSR Journals
This paper aims at identifying an effective and appropriate method of calculating the cost of transporting goods from several supply centers to several demand centers out of many available methods. Transportation algorithms of North-West corner method (NWCM), Least Cost Method (LCM), Vogel’s Approximation Method (VAM) and Optimality Test were carried out to estimate the cost of transporting produced newspaper from production center to ware-houses using Statistical software called TORA. The results revealed that: NWCM = 36,689,050.00, LCM = 55,250,034.00, VAM = 29,097,700.00 and Optimal solution = 19,566,332.00. It was discovered that Vogel’s Approximation method gives the transportation cost that closer to optimal solution. Also, the study revealed that a production center should be created at northern part of Nigeria to replace the dummy supply center used in the analysis, so as to make production capacity equal to requirement.
Optimal Allocation Policy for Fleet ManagementYogeshIJTSRD
The transportation problem is one of the biggest problem that face the fleet management, whereas the main objectives for the fleet management is reducing the operations cost besides improving the fleet efficiency. Therefore, this paper presents an application for a transportation technique on a company to distribute its products over a wide country by using its fleet. All the necessary data are collected from the company, analyzed and reformulated to become a suitable form to apply a transportation model to solve it. The results show that using this technique can be considered as powerful tool to improve the operation management for any fleet. Mohamed Khalil | Ibrahim Ahmed | Khaled Abdelwahed | Rania Ahmed | Elsayed Ellaimony "Optimal Allocation Policy for Fleet Management" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-3 , April 2021, URL: https://www.ijtsrd.com/papers/ijtsrd38673.pdf Paper URL: https://www.ijtsrd.com/management/operations-management/38673/optimal-allocation-policy-for-fleet-management/mohamed-khalil
MODIFIED VOGEL APPROXIMATION METHOD FOR BALANCED TRANSPORTATION MODELS TOWARD...IAEME Publication
This paper is built on a study in relation to transportation problem as it affects most organisational decision in a decomposed setting. The case study used in this work is Dangote cement factory (in Ibese, Nigeria) with three sources and four destinationscentres. The factory is supported by increasing number of cement delivery trucks. Some models for solving balanced transportation problems (TPs) are considered in order to determine the optimal and initial basic feasible solutions (IBFS). From the analysis, it is observed that Modified Vogel Approximation Method (MVAM) is a better method. This is partly because MVAM considers each unit cost in its solution algorithm and minimises total cost comparatively with Vogel Approximation Method (VAM). The results arefurther justified and validated using windows version 2.00 Tora package.
Optimizing Waste Collection In An Organized Industrial Region: A Case Studyertekg
Download Link > https://ertekprojects.com/gurdal-ertek-publications/blog/optimizing-waste-collection-in-an-organized-industrial-region-a-case-study/
In this paper we present a case study which involves the design of a supply chain network for industrial waste collection. The problem is to transport metal waste from 17 factories to containers and from containers to a disposal center (DC) at an organized region of automobile parts suppliers. We applied the classic mixed-integer programming (MIP) model for the two-stage supply chain to the solution of this problem. The visualization of the optimal solution provided us with several interesting insights that would not be easily discovered otherwise.
HOPX Crossover Operator for the Fixed Charge Logistic Model with Priority Bas...IJECEIAES
In this paper, we are interested to an important Logistic problem modelised us optimization problem. It is the fixed charge transportation problem (FCTP) where the aim is to find the optimal solution which minimizes the objective function containig two costs, variable costs proportional to the amount shipped and fixed cost regardless of the quantity transported. To solve this kind of problem, metaheuristics and evolutionary methods should be applied. Genetic algorithms (GAs) seem to be one of such hopeful approaches which is based both on probability operators (Crossover and mutation) responsible for widen the solution space. The different characteristics of those operators influence on the performance and the quality of the genetic algorithm. In order to improve the performance of the GA to solve the FCTP, we propose a new adapted crossover operator called HOPX with the priority-based encoding by hybridizing the characteristics of the two most performent operators, the Order Crossover (OX) and Positionbased crossover (PX). Numerical results are presented and discussed for several instances showing the performance of the developed approach to obtain optimal solution in reduced time in comparison to GAs with other crossover operators.
The selection of third party logistics (TPL) providers is an important issue for enterprises to
outsource their logistics business. In this paper we propose a comprehensive evaluation model for TPL
suppliers based on AHP method. Furthermore, we Base on the evaluation index system including logistics cost,
the logistics operation efficiency and the basic qualities of service. The efficiency and application of the
proposed approach has been illustrated with a case study in Emergency Department of Sfax hospital
On The Use of Transportation Techniques to Determine the Cost of Transporting...IOSR Journals
This paper aims at identifying an effective and appropriate method of calculating the cost of transporting goods from several supply centers to several demand centers out of many available methods. Transportation algorithms of North-West corner method (NWCM), Least Cost Method (LCM), Vogel’s Approximation Method (VAM) and Optimality Test were carried out to estimate the cost of transporting produced newspaper from production center to ware-houses using Statistical software called TORA. The results revealed that: NWCM = 36,689,050.00, LCM = 55,250,034.00, VAM = 29,097,700.00 and Optimal solution = 19,566,332.00. It was discovered that Vogel’s Approximation method gives the transportation cost that closer to optimal solution. Also, the study revealed that a production center should be created at northern part of Nigeria to replace the dummy supply center used in the analysis, so as to make production capacity equal to requirement.
Optimal Allocation Policy for Fleet ManagementYogeshIJTSRD
The transportation problem is one of the biggest problem that face the fleet management, whereas the main objectives for the fleet management is reducing the operations cost besides improving the fleet efficiency. Therefore, this paper presents an application for a transportation technique on a company to distribute its products over a wide country by using its fleet. All the necessary data are collected from the company, analyzed and reformulated to become a suitable form to apply a transportation model to solve it. The results show that using this technique can be considered as powerful tool to improve the operation management for any fleet. Mohamed Khalil | Ibrahim Ahmed | Khaled Abdelwahed | Rania Ahmed | Elsayed Ellaimony "Optimal Allocation Policy for Fleet Management" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-3 , April 2021, URL: https://www.ijtsrd.com/papers/ijtsrd38673.pdf Paper URL: https://www.ijtsrd.com/management/operations-management/38673/optimal-allocation-policy-for-fleet-management/mohamed-khalil
MODIFIED VOGEL APPROXIMATION METHOD FOR BALANCED TRANSPORTATION MODELS TOWARD...IAEME Publication
This paper is built on a study in relation to transportation problem as it affects most organisational decision in a decomposed setting. The case study used in this work is Dangote cement factory (in Ibese, Nigeria) with three sources and four destinationscentres. The factory is supported by increasing number of cement delivery trucks. Some models for solving balanced transportation problems (TPs) are considered in order to determine the optimal and initial basic feasible solutions (IBFS). From the analysis, it is observed that Modified Vogel Approximation Method (MVAM) is a better method. This is partly because MVAM considers each unit cost in its solution algorithm and minimises total cost comparatively with Vogel Approximation Method (VAM). The results arefurther justified and validated using windows version 2.00 Tora package.
Logistics and Supply Chain: An integrated production, inventory, warehouse lo...FGV Brazil
An integrated production, inventory, warehouse location and distribution model
Author: Lokendra Kumar Devangan
Journal of Operations and Supply Chain Management
Vol 9, No 2 (2016)
FGV's Brazilian School of Public and Business Administration (EBAPE)
Abstract:
This paper proposes an integrated production and distribution planning optimization model for multiple manufacturing locations, producing multiple products with deterministic demand at multiple locations. There are multiple modes of transport from plants to demand locations and warehouses. This study presents a model which allows decision makers to optimize plant production, transport and warehouse location simultaneously to fulfill the demands at customer locations within a multi-plant, multi-product, and multi-route supply chain system when the locations of the plants are already fixed. The proposed model is solved for sample problems and tested using real data from a cement manufacturing company in India. An analysis of the results suggests that this model can be used for various strategic and tactical production and planning decisions.
Plant location selection by using MCDM methodsIJERA Editor
Plant location selection has a critical impact on the performance of manufacturing companies. The cost associated with acquiring the land and facility construction makes the location selection a long-term investment decision. The preeminent location is that which results in higher economic benefits through increased productivity and good distribution network. Both potential qualitative and quantitative criteria’s are to be considered for selecting the proper plant location from a given set of alternatives. Consequently, from the literature survey, it is found that the Multi criteria decision-making (MCDM) is found to be an effective approach to solve the location selection problems. In the present research, an integrated decision-making methodology is designed which employs the two well-known decision making techniques, namely Analytical hierarchy process (AHP), and Preference ranking organization method for enrichment evaluations (PROMETHEE-II) in order to make the best use of information available, either implicitly or explicitly. It is analyze the structure for the solution of plant location problems and to obtain weights of the selected criteria’s. PROMETHEE-II is employed to solve decision-making problems with multiple conflicting criteria and alternatives.
Formulation of a Combined Transportation and Inventory Optimization Model wit...IJERA Editor
Most distribution network design models existing in the literature have focused on minimizing the costs of
inventory and transportation. During the analysis of supply chain of currency management problem it is
observed that the transportation of currency from various sources to various destinations and the required
inventory to be maintained to meet the emerging demands requires formulation of a combined problem. This
framework aims to support the coordination of inventory and transportation activities to properly manage the
inventory profiles and currency flows between source locations and distribution centers. This paper considers a
multi-period inventory and transportation model for a single commodity. The key contribution of this paper is, a
mathematical programming formulation of transportation cum inventory problem is proposed and an algorithm
for this new formulation as a multi period decision process is intended. A numerical example of currency
transportation cum inventory is presented to illustrate the proposed algorithm.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Robust Counterpart Open Capacitated Vehicle Routing (RC-OCVRP) Model in Opti...IJECEIAES
In this paper, the Robust Counterpart Open Capacitation Vehicle Rounting Problem (RC-OCVRP) Model has been established to optimize waste transport in districts Sako and districts Sukarami, Palembang City. This model is completed with the aid of LINGO 13.0 by using Branch and Bound solver to get the optimum route. For Sako districs, the routes are as follows: working area 1 is TPS 1-TPS 2-TPS 3-TPA with distance 53.39 km, working area 2 is TPS 1-TPS 2-TPS 3-TPA with distance 48.14 km, working area 3 is TPS 1-TPA with a distance of 22.98 km, and working area 4 is TPS 1-TPS 2TPS 3-TPS 4-TPA with 45.45 km distance, and obtained the optimum route in Sukarami districts is as follows: working area 1 is TPS 1-TPS 2-TPA 44.39 km, working area 2 is TPS 1-TPS 2-TPS 3-TPA with distance 49.32 km, working area 3 is TPS 1-TPS 3-TPA-TPS 2-TPA with distance 58.57 km, and working area 4 is TPS 1-TPA with a distance of 24.07 km, working area 5 is TPS 1-TPS 3-TPA-TPS 2-TPS 4-TPA with a distance of 77.66 km, and working area 6 is a TPS 1-TPS 2-TPS 3-TPA with a distante 44.94 km.
The Effects of Crossdock Shapes on Material Handling Costsijceronline
Layout design for the cross-docking centers is one of the strategic decision level and critical issue because of its directly effects on material flow efficiency in these areas. At this stage, the size and shapes of the cross-docking center have to be determined by taking into account material handling operations. In this study, the effects of the crossdock shapes on material handling cost from inbound doors to outbound doors are analyzed for different type of cross-docking center layouts. In this content, the shapes of I, L, T, and U for cross-docking centers are considered. In order to identify the best shape of the cross-docking centers, a mathematical model is formulated based on the truck-door assignment problem in cross-docking centers. In computational studies, the proposed mathematical model is performed for different sized problems considering the four building shapes and the best building shape is identified by comparing the total material handling costs.
International Journal of Computational Engineering Research(IJCER)ijceronline
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
International Journal of Research in Engineering and Science is an open access peer-reviewed international forum for scientists involved in research to publish quality and refereed papers. Papers reporting original research or experimentally proved review work are welcome. Papers for publication are selected through peer review to ensure originality, relevance, and readability.
Spreadsheet Optimization of Flow for WIP Goods at a Yarn and Tire Cord Manufa...Gurdal Ertek
We developed a spreadsheet optimization model to find the optimal material handling policy at a leading yarn and tire cord manufacturer’s facility. The focus of the study is to optimize the movement of looms of yarn and tire cord between two major manufacturing steps. The considered flow network within the
manufacturing facility is a miniature two-stage supply chain, including the middle layer of depots. Movement of material takes place through forklift trucks and cranes, which impose electricity, labor, maintenance, and depreciation costs. After
introducing the company, the facility, and the project goals, we present the underlying linear programming (LP) model and our spreadsheet implementation. The results of our model suggest an annual saving of approximately $22,000 for the facility.
http://research.sabanciuniv.edu.
A New Network Flow Model for Determining the Assortment of Roll Types in Pack...Gurdal Ertek
This paper reports work motivated by a real world assortment problem in packaging industry. A novel network flow model has been developed to solve the problem of selecting the optimal set of roll types for use in production. The model can incorporate fixed costs that depend on the number of elements in the assortment as well as the selected roll types. While the trade-off between inventory cost and cost of waste is resolved optimally through the model, graphical understanding of the trade-off can bring insights into the decision making process.
This graphical analysis has been demonstrated on a computational example.
http://research.sabanciuniv.edu.
Model for Evaluating CO2 Emissions and the Projection of the Transport Sector IJECEIAES
This article presents a system dynamics model to analyze the growth of cars and the effect of different policies on carbon emissions from the transport sector. The simulation model used in this work was built using the methodology of systems dynamics (SD) developed by Jay W. Forrester at the Massachusetts Institute of Technology (MIT). The model was applied to the transport sector of the city of Bogota, Colombia for a period of time between 2005 and 2050. The information used to feed the model comes from reliable sources such as DANE (National Administrative Department of Statistics) and EIA (U.S Energy Information Administration). Four scenarios were proposed that relate urban development policy and environmental policy. The main results indicate that the number of cars in Bogota can reach up to 13 million vehicles in 2050 and the projection of CO2 emissions would reach 34 million TonCO2 in the absence of an appropriate environmental policy.
Logistics and Supply Chain: An integrated production, inventory, warehouse lo...FGV Brazil
An integrated production, inventory, warehouse location and distribution model
Author: Lokendra Kumar Devangan
Journal of Operations and Supply Chain Management
Vol 9, No 2 (2016)
FGV's Brazilian School of Public and Business Administration (EBAPE)
Abstract:
This paper proposes an integrated production and distribution planning optimization model for multiple manufacturing locations, producing multiple products with deterministic demand at multiple locations. There are multiple modes of transport from plants to demand locations and warehouses. This study presents a model which allows decision makers to optimize plant production, transport and warehouse location simultaneously to fulfill the demands at customer locations within a multi-plant, multi-product, and multi-route supply chain system when the locations of the plants are already fixed. The proposed model is solved for sample problems and tested using real data from a cement manufacturing company in India. An analysis of the results suggests that this model can be used for various strategic and tactical production and planning decisions.
Plant location selection by using MCDM methodsIJERA Editor
Plant location selection has a critical impact on the performance of manufacturing companies. The cost associated with acquiring the land and facility construction makes the location selection a long-term investment decision. The preeminent location is that which results in higher economic benefits through increased productivity and good distribution network. Both potential qualitative and quantitative criteria’s are to be considered for selecting the proper plant location from a given set of alternatives. Consequently, from the literature survey, it is found that the Multi criteria decision-making (MCDM) is found to be an effective approach to solve the location selection problems. In the present research, an integrated decision-making methodology is designed which employs the two well-known decision making techniques, namely Analytical hierarchy process (AHP), and Preference ranking organization method for enrichment evaluations (PROMETHEE-II) in order to make the best use of information available, either implicitly or explicitly. It is analyze the structure for the solution of plant location problems and to obtain weights of the selected criteria’s. PROMETHEE-II is employed to solve decision-making problems with multiple conflicting criteria and alternatives.
Formulation of a Combined Transportation and Inventory Optimization Model wit...IJERA Editor
Most distribution network design models existing in the literature have focused on minimizing the costs of
inventory and transportation. During the analysis of supply chain of currency management problem it is
observed that the transportation of currency from various sources to various destinations and the required
inventory to be maintained to meet the emerging demands requires formulation of a combined problem. This
framework aims to support the coordination of inventory and transportation activities to properly manage the
inventory profiles and currency flows between source locations and distribution centers. This paper considers a
multi-period inventory and transportation model for a single commodity. The key contribution of this paper is, a
mathematical programming formulation of transportation cum inventory problem is proposed and an algorithm
for this new formulation as a multi period decision process is intended. A numerical example of currency
transportation cum inventory is presented to illustrate the proposed algorithm.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Robust Counterpart Open Capacitated Vehicle Routing (RC-OCVRP) Model in Opti...IJECEIAES
In this paper, the Robust Counterpart Open Capacitation Vehicle Rounting Problem (RC-OCVRP) Model has been established to optimize waste transport in districts Sako and districts Sukarami, Palembang City. This model is completed with the aid of LINGO 13.0 by using Branch and Bound solver to get the optimum route. For Sako districs, the routes are as follows: working area 1 is TPS 1-TPS 2-TPS 3-TPA with distance 53.39 km, working area 2 is TPS 1-TPS 2-TPS 3-TPA with distance 48.14 km, working area 3 is TPS 1-TPA with a distance of 22.98 km, and working area 4 is TPS 1-TPS 2TPS 3-TPS 4-TPA with 45.45 km distance, and obtained the optimum route in Sukarami districts is as follows: working area 1 is TPS 1-TPS 2-TPA 44.39 km, working area 2 is TPS 1-TPS 2-TPS 3-TPA with distance 49.32 km, working area 3 is TPS 1-TPS 3-TPA-TPS 2-TPA with distance 58.57 km, and working area 4 is TPS 1-TPA with a distance of 24.07 km, working area 5 is TPS 1-TPS 3-TPA-TPS 2-TPS 4-TPA with a distance of 77.66 km, and working area 6 is a TPS 1-TPS 2-TPS 3-TPA with a distante 44.94 km.
The Effects of Crossdock Shapes on Material Handling Costsijceronline
Layout design for the cross-docking centers is one of the strategic decision level and critical issue because of its directly effects on material flow efficiency in these areas. At this stage, the size and shapes of the cross-docking center have to be determined by taking into account material handling operations. In this study, the effects of the crossdock shapes on material handling cost from inbound doors to outbound doors are analyzed for different type of cross-docking center layouts. In this content, the shapes of I, L, T, and U for cross-docking centers are considered. In order to identify the best shape of the cross-docking centers, a mathematical model is formulated based on the truck-door assignment problem in cross-docking centers. In computational studies, the proposed mathematical model is performed for different sized problems considering the four building shapes and the best building shape is identified by comparing the total material handling costs.
International Journal of Computational Engineering Research(IJCER)ijceronline
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
International Journal of Research in Engineering and Science is an open access peer-reviewed international forum for scientists involved in research to publish quality and refereed papers. Papers reporting original research or experimentally proved review work are welcome. Papers for publication are selected through peer review to ensure originality, relevance, and readability.
Spreadsheet Optimization of Flow for WIP Goods at a Yarn and Tire Cord Manufa...Gurdal Ertek
We developed a spreadsheet optimization model to find the optimal material handling policy at a leading yarn and tire cord manufacturer’s facility. The focus of the study is to optimize the movement of looms of yarn and tire cord between two major manufacturing steps. The considered flow network within the
manufacturing facility is a miniature two-stage supply chain, including the middle layer of depots. Movement of material takes place through forklift trucks and cranes, which impose electricity, labor, maintenance, and depreciation costs. After
introducing the company, the facility, and the project goals, we present the underlying linear programming (LP) model and our spreadsheet implementation. The results of our model suggest an annual saving of approximately $22,000 for the facility.
http://research.sabanciuniv.edu.
A New Network Flow Model for Determining the Assortment of Roll Types in Pack...Gurdal Ertek
This paper reports work motivated by a real world assortment problem in packaging industry. A novel network flow model has been developed to solve the problem of selecting the optimal set of roll types for use in production. The model can incorporate fixed costs that depend on the number of elements in the assortment as well as the selected roll types. While the trade-off between inventory cost and cost of waste is resolved optimally through the model, graphical understanding of the trade-off can bring insights into the decision making process.
This graphical analysis has been demonstrated on a computational example.
http://research.sabanciuniv.edu.
Model for Evaluating CO2 Emissions and the Projection of the Transport Sector IJECEIAES
This article presents a system dynamics model to analyze the growth of cars and the effect of different policies on carbon emissions from the transport sector. The simulation model used in this work was built using the methodology of systems dynamics (SD) developed by Jay W. Forrester at the Massachusetts Institute of Technology (MIT). The model was applied to the transport sector of the city of Bogota, Colombia for a period of time between 2005 and 2050. The information used to feed the model comes from reliable sources such as DANE (National Administrative Department of Statistics) and EIA (U.S Energy Information Administration). Four scenarios were proposed that relate urban development policy and environmental policy. The main results indicate that the number of cars in Bogota can reach up to 13 million vehicles in 2050 and the projection of CO2 emissions would reach 34 million TonCO2 in the absence of an appropriate environmental policy.
Application of local search methods for solving a quadratic assignment proble...Gurdal Ertek
This paper discusses the design and application of local search methods to a real-life application at a steel cord manufacturing plant. The case study involves a layout problem that can be represented as a Quadratic Assignment Problem (QAP). Due to the nature of the manufacturing process, certain machinery need to be allocated in close proximity to each other. This issue is incorporated into the objective function through assigning high penalty costs to the unfavorable allocations. QAP belongs to one of the most difficult class of combinatorial optimization problems, and is not solvable to optimality as the number of facilities increases. We implement the well-known local
search methods, 2-opt, 3-opt and tabu search. We compare the solution performances of the methods to the results obtained from the NEOS server, which provides free access to many optimization solvers on the internet.
http://research.sabanciuniv.edu.
A Minimum Spanning Tree Approach of Solving a Transportation Probleminventionjournals
: This work centered on the transportation problem in the shipment of cable troughs for an underground cable installation from three supply ends to four locations at a construction site where they are needed; in which case, we sought to minimize the cost of shipment. The problem was modeled into a bipartite network representation and solved using the Kruskal method of minimum spanning tree; after which the solution was confirmed with TORA Optimization software version 2.00. The result showed that the cost obtained in shipping the cable troughs under the application of the method, which was AED 2,022,000 (in the United Arab Emirate Dollar), was more effective than that obtained from mere heuristics when compared
The purpose of this paper is to perform a structural optimization of a flat thermoplastic plate (tile). This task is developed computationally through the interface between an optimization algorithm and the finite element method with the goal of minimizing the equivalent stress with specified target stress of 2 MPa when applied with a load intensity of 1000N. A 300 x 300 x 20 mm thermoplastic plate was selected for the optimization, which was performed with a tool in MATLAB R2012b known as genetic algorithm accompanied with static analysis in ANSYS 15. The results produced the optimum equivalent stress (δopt) of 2.136 MPa with the optimum dimensions of 305 x 302 x 20 mm. Also, the dimensions of the plate with the optimum value of the equivalent stress were discovered to be within the lower and upper bound dimensions of the plate. The thermoplastic plate object of the optimization was a square plate of 300 x 300mm, and 20 mm thick with isotropic properties and a particular load and boundary conditions were applied on the entire plate.
A Minimum Spanning Tree Approach of Solving a Transportation Probleminventionjournals
: This work centered on the transportation problem in the shipment of cable troughs for an underground cable installation from three supply ends to four locations at a construction site where they are needed; in which case, we sought to minimize the cost of shipment. The problem was modeled into a bipartite network representation and solved using the Kruskal method of minimum spanning tree; after which the solution was confirmed with TORA Optimization software version 2.00. The result showed that the cost obtained in shipping the cable troughs under the application of the method, which was AED 2,022,000 (in the United Arab Emirate Dollar), was more effective than that obtained from mere heuristics when compared.
Multi-Objective Forest Vehicle Routing Using Savings-Insertion and Reactive T...IJERA Editor
This paper focuses on how the competitiveness of forestry companies in Canada is impacted by forest products distribution and transportation costs, especially in the context of exports. We propose a new two steps approach, consisting in building a good initial solution and then improving it to solve multi-objective forest vehicle routing problem. The main objective of this paper is to solve a multi-objective forest vehicle routing problem using the Savings-insertion, followed by the Reactive tabu, with a variable threshold. To that end, first, a mathematical model is established; secondly, our new Savings-insertion builds a good initial solution, and thirdly, our new Reactive tabu with a variable threshold improves the initial solution. The three main objectives are the minimization of number of routes, the minimization of total distance and the minimization of total time by respecting the specified time window and the demand of all customers, which are sometimes important in this field. Finally, the experimental results obtained with our methodology for the named vehicle routing problem are provided and discussed
Super SBM and GM 1,1 Model Approaches for Global Automobileijtsrd
In the success of many enterprises, the development orientation in the future is an important role. The study measures the performance and ranks the automotive companies around the world by the integration of GM 1,1 model in grey theory and Super SBM model in data development analysis DEA . GM 1,1 model is used for predicting the input variables and output variables in the future time. And then, the super SBM model was used for calculating the efficiency score of each automotive company in every term. Estimated values are standard when their average MAPEs are under 38.332 . The empirical results indicate that four good automotive companies attained efficiency in the previous time seven good automotive companies are expected to reach the performance in the future time. The research presents an overview observation of the automotive industry around the world. Thi-Nguyen Nguyen | The-Vinh Do | Quoc-Chien Luu "Super-SBM and GM (1,1) Model Approaches for Global Automobile" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-6 | Issue-1 , December 2021, URL: https://www.ijtsrd.com/papers/ijtsrd47880.pdf Paper URL: https://www.ijtsrd.com/management/strategic-management/47880/supersbm-and-gm-11-model-approaches-for-global-automobile/thinguyen-nguyen
A New Mathematical Model for Minimization of Exceptional Load in Cellular Man...IJRES Journal
This study is devoted to the cell formation problems in cellular manufacturing systems. Starting point of this study is a paper of Mahdavi et.al. which considers only a few factors of production system. In this research, processing times and the frequencies of the parts are also considered. It is assumed that the load of each machine is known and is the multiplication of the processing times and frequencies. In this case cells are formed to achieve the higher loads inside cells. Also, the proposed model is about the case when alternative technologies are available and the objective is to maximize the loads inside cells. Besides the new model, other main contribution of this study is the computational analysis. The results show that the new model is providing acceptable solution within the logical runtimes.
Aerodynamic Drag Reduction for A Generic Sport Utility Vehicle Using Rear Suc...IJERA Editor
The high demand for new and improved aerodynamic drag reduction devices has led to the invention of flow control mechanisms and continuous suction is a promising strategy that does not have major impact on vehicle geometry. The implementation of this technique on sport utility vehicles (SUV) requires adequate choice of the size and location of the opening as well as the magnitude of the boundary suction velocity. In this paper we introduce a new methodology to identifying these parameters for maximum reduction in aerodynamic drag. The technique combines automatic modeling of the suction slit, computational fluid dynamics (CFD) and a global search method using orthogonal arrays. It is shown that a properly designed suction mechanism can reduce drag by up to 9%.
In green logistics, environmentally-friendly vehicles are strongly recommended as a transportation option. One of the green logistics vehicles is the electric vehicle which is a good selection to reduce greenhouse gas emissions. The present paper focused on the location-routing problem in electric vehicles by considering multi-depots and hard and soft time windows in uncertain conditions. We proposed a fuzzy bi-objective mathematical model for electric vehicles with a limitation in charge stations, the dependence of energy consumption to vehicle load, and a simultaneous delivery and pick-up. We used the multi-objectives particle swarm meta-heuristic algorithms based on the Pareto archive and the NSGA-II algorithm to solve this model. To evaluate the validity of the proposed model and algorithms, sample problems of EVRPTW were selected and solved using Gomez software and proposed meta-heuristic algorithms. The validation results for the model and algorithm confirmed that the model is valid, and the salving algorithms can solve the model efficiently and converge to an optimal answer. The comparing results of solving algorithms performance showed that, compared to the NSGA-II algorithm, the MOPSO algorithm has a higher ability in all states to generate higher quality responses and more diversity.
Bi-objective Optimization Apply to Environment a land Economic Dispatch Probl...ijceronline
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
Financial Benchmarking Of Transportation Companies In The New York Stock Exc...ertekg
Download Link > https://ertekprojects.com/gurdal-ertek-publications/blog/financial-benchmarking-of-transportation-companies-in-the-new-york-stock-exchange-nyse-through-data-envelopment-analysis-dea-and-visualization/
In this paper, we present a benchmarking study of industrial transportation companies traded in the New York Stock Exchange (NYSE). There are two distinguishing aspects of our study: First, instead of using operational data for the input and the output items of the developed Data Envelopment Analysis (DEA) model, we use financial data of the companies that are readily available on the Internet. Secondly, we visualize the efficiency scores of the companies in relation to the subsectors and the number of employees. These visualizations enable us to discover interesting insights about the companies within each subsector, and about subsectors in comparison to each other. The visualization approach that we employ can be used in any DEA study that contains subgroups within a group. Thus, our paper also contains a methodological contribution.
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Data Lineage Tracking: Track the flow of data throughout the ecosystem, ensuring transparency and facilitating root cause analysis for errors.
5. Cultivate a Data-Driven Mindset:
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Optimizing waste collection in an organized industrial region: A case study
1. 4th
International Logistics and Supply Chain Management Congress
Martagan, T. G., Ertek, G., Birbil, S. I., Yasar, M., Cakır, A., Okur, N., Gullu, G., Hacıoglu, A. and
Sevim, O. (2006). "Optimizing waste collection in an organized industrial region: A case study.”
4th International Logistics and Supply Chain Congress, İzmir, Turkey.
Note: This is the final draft version of this paper. Please cite this paper (or this final draft) as
above. You can download this final draft from http://research.sabanciuniv.edu.
OPTIMIZING WASTE COLLECTION
IN AN ORGANIZED INDUSTRIAL REGION: A CASE STUDY
Tuğçe Gizem Martağan1, Gürdal Ertek2, Ş. İlker Birbil3, Murat Yaşar,
Ahmet Çakır, Nazım Okur, Gürdal Güllü, Ahmet Hacıoğlu, and Özgür Sevim
Abstract
In this paper we present a case study which involves the design of a supply chain
network for industrial waste collection. The problem is to transport metal waste
from 17 factories to containers and from containers to a disposal center (DC) at an
organized region of automobile parts suppliers. We applied the classic mixed-
integer programming (MIP) model for the two-stage supply chain to the solution
1
Sabancı University, Turkey,
2
Sabancı University, Turkey,
3
Sabancı University, Turkey,
2. 4th
International Logistics and Supply Chain Management Congress
of this problem. The visualization of the optimal solution provided us with several
interesting insights that would not be easily discovered otherwise.
Keywords: Logistics of industrial waste, Supply chain network design, Waste
collection, Waste management, Facility location, Organized industrial regions.
1. Introduction
The problem presented in this paper consists of planning the logistics of industrial waste
collection from factories located in an organized industrial region, to suitable intermediate points
which are possible container locations, and finally to disposal centers. The main process leading
to solution of this waste collection problem is designing a network model according to the cost
analysis, and determining waste container locations based on their capacities and locations. The
problem can be treated as a transhipment problem aiming to select the best intermediate points
for waste transfer while minimizing transportation costs in the waste collection network (Section
2). After building the model and reaching the optimal solution minimizing the total cost, a Java
program that can read input files was coded in order to visualize the solution (Section 3). At the
visualization stage, the values of the parameters and variables were mapped to the sizes of the
nodes and thickness of the arcs.
Figure 1. The candidate container locations displayed on a map of TOSB.
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International Logistics and Supply Chain Management Congress
The industrial waste collection problem discussed in this paper was done as a graduation project
at Sabancı University in 2005-2006 academic year. Distinguishing aspects of this study are that
the problem is an example of environmental operations research is based on an estimate of real
world data and that visualization is carried out. The used method and obtained solution have
practical aspects which make them be easily adoptable to the one of the problems of organized
industrial regions. This has also environmental contributions because of the fact that collected
industrial waste such as metals are recycled. Furthermore, network visualization obtained by Java
in the final phase leads to a better understanding of the solution and assessment of the designed
supply chain network.
In the model, data from TOSB (TAYSAD Organize Sanayi Bölgesi - TAYSAD Organized Industrial
Region) was used. The reasons for selecting to develop a model with TOSB (TOSB) data were as
follows:
TAYSAD (Taşıt Araçları Yan Sanayicileri Derneği, Association of Automotive Parts &
Components Manufacturers), founded in 1978, is the most powerful association in the
automobile parts supplier industry with %65 market share in Turkey. TAYSAD companies
operate especially in Istanbul, Kocaeli and Bursa. TAYSAD is also a member of CLEPA,
European Association of Automotive Suppliers.
TOSB consists of 59 of 170 members of TAYSAD. Founded on a 625 acre (2.53 km2) of
land, TOSB is one of the most important industrial regions chosen by Turkish and as well
as foreign automotive parts manufacturers. Additionally, Turkish automotive parts
supplier industry has approximately 700 firms operating with latest technology and makes
%70 of its exports to European Union countries. This industry has a considerable
contribution to the Turkish economy: In 2003, $2.4 billion of exports were achieved by
Turkish automotive parts suppliers.
The fact that TOSB is located in Gebze, within close proximity of Sabancı University has
highly motivated us as the project team, since we would have a chance to suggest a solution
to a practical real-world problem in our neighbourhood. Meanwhile, Sabancı University
has close ties with TAYSAD thanks to common projects between The Competitiveness
Forum (Competitiveness Forum) of Sabancı University and TAYSAD.
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International Logistics and Supply Chain Management Congress
2. The Model
In TOSB, 17 factories, 5 candidate container locations and one disposal center (DC) where total
waste will be sent are available (Figure 1). Different amounts of waste from each factory are sent
to suitable container locations from where they will be than transferred to the DC. The objective is
to minimize total transportation cost under capacity constraints for the containers. This supply
chain network design problem contains three sets of nodes (factories, containers and DC) and two
sets of arcs (from factories to containers and from containers to the DC), hence the name two-
stage supply chain. The set I represents factories which are the source nodes producing wi tons of
waste monthly. Intermediate nodes representing candidate container locations constitute the set
J. In these sites indexed by j, container location decisions are reflected by binary variables zj.
There are three sets of decision variables: zj, xij, yj representing location and flow decisions. Since
binary variables are present in the model together with continuous variables, the problem can be
classified as a mixed integer programming (MIP) problem. The model is given bellow:
SETS
I : set of factories, ni ,,1
J : set of candidate container locations, mj ,,1
PARAMETERS
ija : cost of sending one ton of waste from factory i to container location j
jb : cost of sending one ton of waste from container location j to DC
iw : monthly waste amount of factory i
C : maximum monthly capacity of each container
jf : monthly fixed cost of operating a container at container location j
VARIABLES
jz : 1, if a container is located at container location j ; 0 otherwise
ijx : amount of monthly flow of waste from factory i to container location j
jy : amount of monthly flow of waste from container location j to disposal center (DC)
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International Logistics and Supply Chain Management Congress
Min
Jj
jj
Jj
jj
Ii Jj
ijij ybzfxa
s.t.
jj Czy Jj (1) Capacity and Linking constraints
j
Ii
ij yx
Jj (2) Flow balance constraints: Containers
i
Jj
ij wx
Ii (3) Flow balance constraints: Factories
jz binary; 0, jij yx (4) Binary jz and Nonnegativity
In the objective function, the total cost in the supply chain is to be minimized: The first
summation represents the total cost of transferring waste from factories to container locations;
the second summation represents the total fixed cost of opened containers (assuming that each
container has a lifetime of one year); and the last summation represents the total cost of
transferring waste from containers to the DC.
The constraints are as follows:
1. The first constraint set representing capacity constraints assures that monthly flow of
waste from container location j does not exceed the maximum monthly capacity. As can be
observed, the capacity of every container is assumed to be identical, namely C. This
constraint set also links the selection of container location j to the monthly waste flow from
that container to DC. There can be a monthly flow from container location j to DC only if a
container is located at a container location j.
2. The second constraint set assures that the total amount of waste coming from different
factories to a container j is the same as the total amount of waste transferred from that
container j to the DC.
3. The third constraint set ensures that outgoing waste from a factory i is equal to its
monthly amount of waste.
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International Logistics and Supply Chain Management Congress
4. The fourth constraint set specifies that the zj are binary and that the other variables are
nonnegative
In order to solve the model presented above, we have decided to use GAMS (General Algebraic
Modelling Systems), a high-level modeling system for mathematical programming and
optimization (GAMS). We have decided to use CPLEX (ILOG) as the MIP solver. The model is
built based on the TOSB data, which contains 17 factories, 5 candidate container locations and
one DC. The complete GAMS model is given in Appendix A. We would like to remark that the real
world values are distorted and thus hidden in the given GAMS model due to confidentiality
issues. However the magnitude of costs are of the same scale. Construction of the model required
the declaration of sets I and J and their elements as I = {f1, f2, f3,…., f16, f17} and J = {c1,c2, c3,
c4, c5}, respectively. The maximum monthly capacity C of each container is taken as 600 tons.
Distances are calculated based on the actual road structure of TOSB for each arc and then the
costs on the arcs are determined by taking fuel costs and staff expenses into account. All of the
costs are monthly and in terms of YTL (new Turkish lira).
In the optimal solution, minimum monthly cost of the waste transfer from factories to container
locations and then to the DC is 70,338 YTL (approximately $48,000). Three container locations
(c1, c3, c4) out of the five candidates were selected to be opened by the solver.
3. Network Visualization
Following the development of the mathematical model and the GAMS model, we have carried
out a visualization of the solution that was found by CPLEX. Visualization can dramatically
enhance one’s understanding of the optimization results and enable perception of useful and
interesting insights. Some supply chain design/optimization software (CIMPEL, HKUST,
Llamasoft, LogisticTools, Logistics Simulation, The Logistics Institute) are known to visually
represent supply chain networks. Meanwhile, the paper by Camm et al. (1997) is a supply chain
classic from the operations research / industrial engineering literature. In their paper, the
authors describe an optimization based information system that is supported by GIS
(Geographical Information System) visualization. The system they describe is reported to save
more than $200 million for the consumer products giant Procter & Gamble.
The visualization in our study (Figure 2) was carried out through a simple Java program that
reads two input files, namely problem.txt and solution.txt (given in Appendix B with distorted
parameter values, ex: factory coordinates and flows). In this visualization only the containers that
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International Logistics and Supply Chain Management Congress
appear in the optimal solution are displayed. Each factory is represented by a circle filled with
blue. The magnitudes of the flows between nodes are reflected in the thickness of the arcs. Flows
in the first stage (factories and containers) of the supply chain are represented by red arcs and
flows in the second stage (containers and DC) are represented by black arcs. The arc labels denote
the amount of flows on the arcs in tons.
Figure 2. The Java visualization of the optimal supply chain network.
From Figure 2 one can observe that there exists a significant amount of flow from factories 8
and 16 (f8, f16) to container 4 (c4). Meanwhile there exist relatively significant amounts of flow
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International Logistics and Supply Chain Management Congress
from factories 4, 9, 12 (f4, f9, f12) to container 1 (c1). By observing the thickness of the black arcs
from containers 1 and 4 to the DC, one can conclude that these two containers are utilized to full
capacity. On the other hand, container 3 is not utilized to full capacity, since the arc from that
container to the DC is approximately half as thick as the other black arcs. All the factories send
their waste to a single container (single-sink), except factories 4 and 15 (f4, f15).
The visualization of the network allowed us to make the above observations, which would be
very hard to make by looking at the text output of the GAMS solution. Thus we believe that the
extra effort spent for the visualization is highly justified.
4. Related Literature
Amponsah and Salhi (2004) argue that waste collection problem is one of the most crucial
problems for large cities and local authorities. Waste collection and solid waste management pose
importance since some wastes contain toxic and hazardous ingredients, where some others are
recycled. Literature contains studies focusing on efficient waste collection, supply chain network
designs leading to operational cost savings. There are many related problems, including Vehicle
Routing Problem (VRP), where the main aim is to incur the minimum total cost while routing
multiple numbers of vehicles, going out from a depot, visiting intermediate nodes and returning
back to the depot. (Tung, D. V., Pinnoi, A., 1999). Minimizing number of vehicles can be another
objective in VRP. Vehicle Scheduling and Routing Problem (VSRP) can be considered as an
extension of VRP with time periods and place requirements constraints (Johansson, O. M.,
2005). Additionally, Vehicle Routing Problem with Time Windows (VRPTW) includes time
windows between which the nodes have to be visited (Kim, B. I. et al., 2005). Other problem
variants include Periodic Vehicle Routing Problem (PVRP) (Teixeira et al., 2004) and Capacitated
Arc Routing Problem (CARP) (Chu, et al., 2004).
The model which is most related to the network design problem in this paper is presented by
Rahman et al. (1995). The authors refer to the problem as the Solid Waste Transfer Stations
(SWTS) location problem and solve it for the City of Phoenix, Arizona. Their model aims to select
the most suitable intermediate nodes to transfer materials with the objective of minimizing
transportation costs. In their paper, they also develop an additional approach to SWTS by
minimizing public opposition.
It is also possible to find out several works about waste management in Turkey. For example,
Koçer et al. (2003) investigated waste collection, waste transfer costs and waste disposal areas in
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International Logistics and Supply Chain Management Congress
Elazığ, Turkey. In their research, they considered criteria such as location of the waste area,
population, daily amount of waste, container capacities, weight of waste, costs, time, and
productivity in waste management. They conclude that first of all, records for waste quantities
and costs should be kept and secondly the number of workers, distances of transportation,
capacities of the containers and their technical capabilities affect productivity. Another research
is done by Karagüzel and Mutlutürk (2005), who considered geological, hydro geological,
topographical criteria and observed environmental protection areas, land sliding and flooding in
order to select the most suitable waste area in Isparta, Turkey. Demir et al. (2001) studied the
design of waste transportation and waste collection in Yenimahalle, Ankara, Turkey. They have
developed a long-term and short-term plan for waste collection and logistics and selected the
transfer stations. They have developed a mathematical model similar to the one presented in our
paper but additionally, they also considered allocation of trucks to collection areas, frequency of
the collections and definition of the optimal roads. Their study also includes financial analysis.
5. Conclusions
We have presented the application of optimization to a real-world industrial waste collection
problem. Two distinguishing aspects of our study are the following:
1. The model was built using real-world data provided by the management of the
industrial region and estimated values which we believe are close enough to the real values
(however, the values given in the paper for the model and its solution are distorted due to
confidentiality agreements).
2. The optimal solution was visualized, enabling the observation of several interesting
issues.
Mathematical programming, specifically mixed integer programming (MIP) is an essential tool to
model and solve strategic and tactical managerial problems of industrial regions. Industrial
regions in developing countries such as Turkey can highly benefit from this approach, as
illustrated in our study. Meanwhile, visualization can contribute greatly to the usability and thus
acceptance of optimization models in industry.
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6. References
Amponsah, S. K., Salhi, S. 2004. The investigation of a class of capacitated arc routing problems:
the collection of garbage in developing countries. Waste Management, 24: 711–721.
CIMPEL. http://www2.isye.gatech.edu/~mgoetsch/research.html#Cimpel
Camm, J. D., Chorman, T. E., Dill, F. A., Evans, J. R., Sweeney, D. J., Wegryn, G. W. 1997.
Blending OR/MS, judgment, and GIS: Restructuring P&G’s supply chain. Interfaces, 27: 128-
142.
Chu, F., Labadi, N., Prins, C. 2004. Heuristics for the periodic capacitated arc routing problem.
Journal of Intelligent Manufacturing, 16: 243-251.
Competitiveness Forum. http://www.ref.sabanciuniv.edu
Demir, E., Gültekin, D., Sandıkçıoğlu, S., Şayhan, A., Yeşildağ, M., Kırca, Ö., Süral, H.,
Yenimahalle Belediyesi Katı Atık Toplama ve Taşıma Sistemleri tasarımı. Endüstri
Mühendisliği Dergisi, 12(3-4): 52-64.
GAMS. http://www.gams.com
HKUST. http://www1.ieem.ust.hk/research/project_img/web9_l.jpg
ILOG. http://www.ilog.com
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Johansson, O. M., 2006. The effect of dynamic scheduling and routing in a solid waste
management system. Waste Management, 26: 875-885.
Karagüzel, R., Mutlutürk, M., 2005. Katı atık depolamada yer seçimi: Isparta örneği.
Mühendislik Jeolojisi Bülteni, 21: 19-33.
Kim, B. I., Kim, S., Sahoo, S. 2006. Waste collection vehicle routing problem with time windows.
Computers & Operations Research, 33: 3627-3642.
Koçer, N., Öbek, E., Uslu, G. 2003. Elazığ kentinde atıkların toplama ve taşıma maliyeti ile çöp
sahasının durumu. Fırat Üniversitesi Fen ve Mühendislik Dergisi, 15(2): 173-182.
Llamasoft. http://www.llamasoft.com/network.html
LogicTools. http://logic-tools.com
Logistics Simulation. http://www.logsim.co.uk/index.htm
Rahman, M., Kuby, M. 1995. A multiobjective model for locating solid waste transfer facilities
using an empirical opposition function. INFOR, Ottowa, 33: 34-49
TAYSAD. http://www.taysad.org.tr
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Teixeira, J., Antunes, A. P., de Sousa, J. P. 2004. Recyclable waste collection planning - a case
study. European Journal of Operational Research, 543-554.
The Logistics Institute. http://www.tli.gatech.edu/research/projects/detail.php?id=22
TOSB. http://www.tosb.com.tr
Tung, D. V., Pinnoi, A. 1999. Vehicle routing-scheduling for waste collection in Hanoi.
European Journal of Operational Research, 125: 449-468.
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Appendix A. The GAMS Model
SETS
I Factories / f1*f17 /
J Container Locations / c1*c5 /
DC Disposal Center /d1/ ;
PARAMETERS
F(J) fixed monthly cost
/ c1 626
c2 626
c3 1252
c4 750
c5 750
/
W(I) average monthly waste amount of factory i
/
f1 25
f2 75
f3 15
f4 120
f5 45
f6 30
f7 20
f8 270
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f9 140
f10 35
f11 80
f12 170
f13 55
f14 70
f15 90
f16 240
f17 25
/
B(J) unit cost per ton from location j to dc
/ c1 36
c2 40
c3 36
c4 32
c5 44
/ ;
TABLE A(I,J) unit cost per ton from factory i to location j
c1 c2 c3 c4 c5
f1 26 16 6 32 24
f2 32 16 10 20 34
f3 30 32 22 46 6
f4 18 14 28 4 46