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Abstract - In this paper we suggest an evolutionary computational approach by applying a combination of a genetic algorithm and a tabu search to obtain a good solution for relatively large unidirectional automated guided vehicle flowpath... more
Abstract - In this paper we suggest an evolutionary computational approach by applying a combination of a genetic algorithm and a tabu search to obtain a good solution for relatively large unidirectional automated guided vehicle flowpath design problems. Unidirectional flowpaths are used to ...
Research Interests: Computer Science, Genetic Algorithms, Linear Programming, Tabu Search, Industrial Engineering, and 10 moreTraffic control, Genetic Algorithm, Path planning, System Design, Computation, Evolutionary Computing, Mathematical Optimization, Mathematical Model, Path Planning, and Automated Guided Vehicle (AGV)
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A process planning system using case-based reasoning (CBR) is developed for block assembly in shipbuilding. A block assembly planning problem is modeled as a constraint satisfaction problem where the precedence relations between... more
A process planning system using case-based reasoning (CBR) is developed for block assembly in shipbuilding. A block assembly planning problem is modeled as a constraint satisfaction problem where the precedence relations between operations are considered constraints. In order ...
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The armed forces of major nations have utilized modeling and simulation technologies to develop weapon systems corresponding to changing modern battlefields and reducing the development cycle. However, model design is complex owing to the... more
The armed forces of major nations have utilized modeling and simulation technologies to develop weapon systems corresponding to changing modern battlefields and reducing the development cycle. However, model design is complex owing to the characteristics of current weapons, which require multiple functions. Therefore, this study proposes a method to support the automated design of weapon system models for simulation. We apply module-based modeling and an intelligent modeling process to our devised method. The former formalizes constituents and constraints regarding an element combination to design the required model, while the latter applies case-based reasoning (CBR) to intelligentize the modeling process based on the results of the former. Using a case study, our proposed method demonstrates that models that respond to operational circumstances can be designed based on simulation results. Consequently, when weapon systems can be represented in formalized structures and constituent...
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Ship block assembly planning is very complex due to the various activities and characteristics of ship production. Therefore, competitiveness in the shipbuilding industry depends on how well a company operates its ship block assembly... more
Ship block assembly planning is very complex due to the various activities and characteristics of ship production. Therefore, competitiveness in the shipbuilding industry depends on how well a company operates its ship block assembly plan. Many shipbuilders are implementing various studies to improve their competitiveness in ship block assembly planning, specifically regarding technology usage, such as modeling and simulation (M&S) and Cyber-Physical Systems (CPS). Although these technologies are successfully applied in some production planning systems, it is difficult to tailor ship production planning systems with flexibility due to unexpected situations. Providing a flexible plan for these production planning systems requires a way to describe and review the organic relationships of ship production processes. In this research, a process-based modeling (PBM) method proposes a novel approach to describing the production process of ship block assembly planning by redefining producti...
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... Yoonho Seo*, Tae-Hoon Choi*, Suk-Hwan Suh ... public void MachineControlVrml(String AxisX, String AxisY, String AxisZ){ try{ AxisNodeX = browser.getNode(AxisX); AxisInX = (EventInSFVec3f ) AxisNodeX.getEventIn(... more
... Yoonho Seo*, Tae-Hoon Choi*, Suk-Hwan Suh ... public void MachineControlVrml(String AxisX, String AxisY, String AxisZ){ try{ AxisNodeX = browser.getNode(AxisX); AxisInX = (EventInSFVec3f ) AxisNodeX.getEventIn( "set-translation"); AxisOuiY = (EventOutSFVec3f) AxisNodeX ...
Research Interests: Computer Science, Computer Aided Manufacturing, Industrial Engineering, Directed graphs, Machine Intelligence, and 12 morecomputer Integrated manufacturing, Machine Tools, Vrml, Virtual Machine, World Wide Web, Numerical Control, Science Technology, Modeling Techniques, Internet, Www, Solid Modeling, and Machine Tool
3 Recently, air attacks with increasing kill rates and improving accuracy have become very threatening in wars. When national facilities are attacked by enemy aircraft, ground forces constitute the air defense system, which consists of an... more
3 Recently, air attacks with increasing kill rates and improving accuracy have become very threatening in wars. When national facilities are attacked by enemy aircraft, ground forces constitute the air defense system, which consists of an air-defense radar and a Surface-to-Air Missile (SAM) battery. The development of an air-defense radar and a SAM battery entails time and cost, besides considerations of the scope of the test. To overcome those limitations, Modeling and Simulation (M&S) techniques have been applied for tests of state-of-the-art weapon systems. The object of this paper is to propose and develop a simulator for the "interceptive performance" of a SAM system from a practical standpoint. We analyze different results of the simulator and find the best condition with regard to intercepting aircraft through simulation experiments. The operation of the developed simulator consists of three phases. The air-defense radar detects the aircraft and then assigns a guida...
Modeling and simulation techniques construct experimental environment considering battlefields and are able to analyze performance of components of weapon system that closely resemble reality. However, developed model has low scalability... more
Modeling and simulation techniques construct experimental environment considering battlefields and are able to analyze performance of components of weapon system that closely resemble reality. However, developed model has low scalability and not cared reusability because it has been used only in a limited range of domain. In this paper, we develop a verification tool to verify reusability of developed component for dynamic reconfiguration and to judge scalability of it and a management tool to control data of it effectively. In addition, dynamic reconfiguration architecture of guided weapon systems designed in the previous study has been applied to SAM(Surface to Air Missile) System Simulator, and we study effectiveness of the developed component. Thus the user can configure various guided weapon systems through simulation application of dynamic reconfiguration architecture of component.
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1. Introduction To design manufacturing systems is a very complic and a generic process of a human being. Analyzing and formalizing the design procedure of a manufacturing system could achieve the design automation. Manufacturing systems... more
1. Introduction To design manufacturing systems is a very complic and a generic process of a human being. Analyzing and formalizing the design procedure of a manufacturing system could achieve the design automation. Manufacturing systems are designed and developed for ...
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Abstract - In this paper, we focus on a new facility location problem, in which a facility in each period can be reconfigured, and opened or closed according to changing customer demand. To solve this problem, a mixed-integer programming... more
Abstract - In this paper, we focus on a new facility location problem, in which a facility in each period can be reconfigured, and opened or closed according to changing customer demand. To solve this problem, a mixed-integer programming model is developed and ...
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Abstract In this paper, we consider an integrated Resource Selection and Operation Sequences (iRS/OS) problem in Intelligent Manufacturing System (IMS). Several kinds of objectives are taken into account, in which the makespan for orders... more
Abstract In this paper, we consider an integrated Resource Selection and Operation Sequences (iRS/OS) problem in Intelligent Manufacturing System (IMS). Several kinds of objectives are taken into account, in which the makespan for orders should be minimized; workloads among ...
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ABSTRACT Machines and automated guided vehicles (AGVs) scheduling problems are two essential issues that need to be addressed for the efficiency of the overall production system. The purpose of this paper is to study the simultaneous... more
ABSTRACT Machines and automated guided vehicles (AGVs) scheduling problems are two essential issues that need to be addressed for the efficiency of the overall production system. The purpose of this paper is to study the simultaneous scheduling problem of machines and AGVs in a flexible manufacturing system (FMS) since the global optimum cannot be reached by considering each of them individually. In this paper, a mixed integer linear programming (MILP) model is developed with the objective of makespan minimisation. The MILP model consists of the following two constraint sets: machines and AGVs scheduling sub-problems. As both sub-problems are known to be NP-hard, a heuristic algorithm based on tabu search (TS) is proposed to get optimal or near to optimal solution for large-size problems within reasonable computation time. The proposed algorithm includes a novel two-dimensional solution representation and the generation of two neighbour solutions, which are alternately and iteratively applied to improve solutions. Moreover, an improved lower bound calculation method is introduced for the large-size problems. Computational results show the superior performance of the TS algorithm for the simultaneous scheduling problem.
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ABSTRACT The facility layout problem (FLP) is to arrange facilities within a given area so as to minimise the total material-handling cost. An efficient arrangement of facilities plays an important part in the achievement of high... more
ABSTRACT The facility layout problem (FLP) is to arrange facilities within a given area so as to minimise the total material-handling cost. An efficient arrangement of facilities plays an important part in the achievement of high productivity in a manufacturing system. This paper focuses on the layout design of unequal-sized facilities with fixed shapes and input/output (I/O) points. A mixed-integer programming (MIP) model is developed to obtain optimal solutions. Since the MIP model is not applicable to large-sized problems, a two-step heuristic algorithm is developed to solve the FLPs. In the first step, a layout solution with moderate quality is generated by using an interconnected zone algorithm and a simulated annealing (SA) algorithm. The zone algorithm is a newly developed layout construction technique which places facilities successively within designated zones according to a placing sequence. The zone concept is introduced to reduce the solution space such that the computational effort is decreased, while SA is used to search for the placing sequences. The second step improves that solution further using the reduced MIP by employing the relative position information obtained from the first step. Computational experiments indicate that the algorithm in the first step can yield on average a 1.048% improvement on the best solutions obtained by the existing algorithms. The second step can further improve the solutions obtained in the first step by 0.484% on average. Compared to the commercial software VIP-PLANOPT 2006 (Engineering Optimization Software 2005), the proposed two-step algorithm improves the solutions by 9.113% on average.
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This paper deals with the advanced planning problem for minimizing makespan with workload balancing considering capacity constraints, precedence relations, and alternative resources with different operation times in a multi-plant chain.... more
This paper deals with the advanced planning problem for minimizing makespan with workload balancing considering capacity constraints, precedence relations, and alternative resources with different operation times in a multi-plant chain. The problem is formulated as a multi-...
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Most shops currently maintain a single process plan for each part type manufactured by the shop even when multiple process plans are feasible to produce the part. The use of a static process plan for a part regardless of the product mix... more
Most shops currently maintain a single process plan for each part type manufactured by the shop even when multiple process plans are feasible to produce the part. The use of a static process plan for a part regardless of the product mix and volume robs the shop of production flexibility and efficiency. In this paper, given that multiple process plans
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... Page 6. 1140 Y. Seo and P. J. Egbelu Unidirectional AGVguidepath layout Figure 3. Flexible AGV guidepath design. 3.1. ... In the case that no candidate paths are available for a flow link Lki at level K + I, a dummy path Rkio is... more
... Page 6. 1140 Y. Seo and P. J. Egbelu Unidirectional AGVguidepath layout Figure 3. Flexible AGV guidepath design. 3.1. ... In the case that no candidate paths are available for a flow link Lki at level K + I, a dummy path Rkio is selected: ie, ad1=aK+Rkio, and a,,+l=a"-Lki. ...
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Int. J. Manufacturing Technology and Management, Vol. 5, Nos. 1/2, 2003 ... Machine selection considering workload balance at the parts fabrication stage of ship hull construction ... School of Industrial Engineering, University of Ulsan,... more
Int. J. Manufacturing Technology and Management, Vol. 5, Nos. 1/2, 2003 ... Machine selection considering workload balance at the parts fabrication stage of ship hull construction ... School of Industrial Engineering, University of Ulsan, Namku, Ulsan, Korea (680-749) E-mail: ...
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ABSTRACT In this paper, an improved particle swarm optimization (PSO) algorithm is proposed for the resource-constrained project scheduling problem (RCPSP) which is widely applied in advanced manufacturing, production planning, and... more
ABSTRACT In this paper, an improved particle swarm optimization (PSO) algorithm is proposed for the resource-constrained project scheduling problem (RCPSP) which is widely applied in advanced manufacturing, production planning, and project management. The algorithm treats the solutions of RCPSP as particle swarms and employs a double justification skill and a move operator for the particles, in association with rank-priority-based representation, greedy random search, and serial scheduling scheme, to execute the intelligent updating process of the swarms to search for better solutions. The integration combines and overhauls the characteristics of both PSO and RCPSP, resulting in enhanced performance. The computational experiments are subsequently conducted to set the adequate parameters and compare the proposed algorithm with other approaches. The results suggest that the proposed PSO algorithm augments the performance by 9.26, 16.17, and 10.45 % for the J30, J60, and J120 instances against the best lower bound-based PSO currently available, respectively. Moreover, the proposed algorithms demonstrate obvious advantage over other proposals in exploring solutions for large-scale RCPSP problems such as the J60 and J120 instances.