The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform
Rafael Pastor - One of the best experts on this subject based on the ideXlab platform.
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LB-ALBP: the lexicographic bottleneck Assembly Line Balancing problem
International Journal of Production Research, 2010Co-Authors: Rafael PastorAbstract:The classic Assembly Line Balancing problem (ALBP) basically consists of assigning a set of tasks to a group of workstations while maintaining the tasks’ precedence relations. When the objective is to minimise the number of workstations m for a given cycle time CT, the problem is referred to as ALBP-1; if the objective is to minimise CT given m, then the problem is called ALBP-2. The only objective in ALBP-2 is to minimise CT, i.e., the workload of the most heavily loaded workstation (the bottleneck). However, considering the second-biggest, third-biggest, etc. workloads, can be important. Distributing a workload among six workstations as 10, 10, 10, 4, 3, 3, is not the same as distributing it as 10, 6, 6, 6, 6, 6. The CT value is the same, but the second distribution is beyond question more reliable and balanced. In this paper, we present and formalise a new Assembly Line Balancing problem: the lexicographic bottleneck Assembly Line Balancing problem (LB-ALBP). The LB-ALBP hierarchically minimises the wo...
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LB-ALBP: The Lexicographic Bottleneck Assembly Line Balancing Problem
International Journal of Production Research, 2010Co-Authors: Rafael PastorAbstract:The classic Assembly Line Balancing problem (ALBP) basically consists of assigning a set of tasks to a group of workstations while maintaining the tasks' precedence relations. When the objective is to minimize the number of workstations m for a given cycle time CT, the problem is referred to as ALBP-1; if the objective is to minimize CT given m, then the problem is called ALBP-2. The only objective in ALBP-2 is to minimize CT, i.e., the workload of the most heavily loaded workstation (the bottleneck). However, considering the second-biggest and third-biggest etc. workloads, can be important. Distributing a workload among six workstations as 10, 10, 10, 4, 3, 3, is not the same as distributing it as 10, 6, 6, 6, 6, 6. The CT value is the same, but the second distribution is beyond question more reliable and balanced. In this paper, we present and formalize a new Assembly Line Balancing problem: the Lexicographic Bottleneck Assembly Line Balancing Problem (LB-ALBP). The LB-ALBP hierarchically minimizes the workload of the most heavily loaded workstation (CT), followed by the workload of the second most heavily loaded workstation, followed by the workload of the third most heavily loaded workstation, and so on. We present two mixed-integer Linear programming (MILP) models designed to solve the LB-ALBP optimally, together with three heuristic procedures based on these MILPs.
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ASALBP: The Alternative Subgraphs Assembly Line Balancing Problem
International Journal of Production Research, 2008Co-Authors: Liliana Capacho, Rafael PastorAbstract:Assembly Line Balancing problems basically consist in assigning a set of tasks to a group of workstations while maintaining the tasks' precedence relations, which are represented by a predetermined precedence graph. However, one or more parts of a product's Assembly process may admit alternative precedence subgraphs, which represent possible Assembly variants. In general, because of the great difficulty of the problem and the impossibility of representing alternative subgraphs in a precedence graph, the system designer will decide to select, a priori, one of such alternative subgraphs. This paper presents, characterizes and formulates a new general Assembly Line Balancing problem with practical relevance: the Alternative Subgraphs Assembly Line Balancing Problem (ASALBP). Its novel characteristic is that it considers the possibility of having alternative Assembly subgraphs, with the processing times and/or the precedence relations of certain tasks dependent on the Assembly subgraph selected. Therefore, solving this problem implies simultaneously selecting an Assembly subgraph for each part of the Assembly that allows alternatives and Balancing the Line. The potentially positive effects of this on the solution of the problem are shown in a numerical example. Finally, a simple mathematical programming model is described and the results of a brief computational experiment are presented.
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ASALBP: the alternative subgraphs Assembly Line Balancing problem
International Journal of Production Research, 2008Co-Authors: Liliana Capacho, Rafael PastorAbstract:Assembly Line Balancing problems basically consist of assigning a set of tasks to a group of workstations while maintaining the tasks’ precedence relations, which are represented by a predetermined precedence graph. However, one or more parts of a product's Assembly process may admit alternative precedence subgraphs, which represent possible Assembly variants. In general, because of the great difficulty of the problem and the impossibility of representing alternative subgraphs in a precedence graph, the system designer will decide to select, a priori, one of such alternative subgraphs. This paper presents, characterizes and formulates a new general Assembly Line Balancing problem with practical relevance: the alternative subgraphs Assembly Line Balancing problem (ASALBP). Its novel characteristic is that it considers the possibility of having alternative Assembly subgraphs, with the processing times and/or the precedence relations of certain tasks dependent on the Assembly subgraph selected. Therefore, so...
Armin Scholl - One of the best experts on this subject based on the ideXlab platform.
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A classification of Assembly Line Balancing problems
European Journal of Operational Research, 2007Co-Authors: Nils Boysen, Malte Fliedner, Armin SchollAbstract:Assembly Lines are special flow-Line production systems which are of great importance in the industrial production of high quantity standardized commodities. Recently, Assembly Lines even gained importance in low volume production of customized products (mass-customization). Due to high capital requirements when installing or redesigning a Line, its configuration planning is of great relevance for practitioners. Accordingly, this attracted attention of many researchers, who tried to support real-world configuration planning by suited optimization models (Assembly Line Balancing problems). In spite of the enormous academic effort in Assembly Line Balancing, there remains a considerable gap between requirements of real configuration problems and the status of research. To ease communication between researchers and practitioners, we provide a classification scheme of Assembly Line Balancing. This is a valuable step in identifying remaining research challenges which might contribute to closing the gap.
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The sequence-dependent Assembly Line Balancing problem
OR Spectrum, 2006Co-Authors: Armin Scholl, Nils Boysen, Malte FliednerAbstract:Assembly Line Balancing problems (ALBP) arise whenever an Assembly Line is configured, redesigned or adjusted. An ALBP consists of distributing the total workload for manufacturing any unit of the products to be assembled among the work stations along the Line. The sequence-dependent Assembly Line Balancing problem (SDALBP) is an extension of the standard simple Assembly Line Balancing problem (SALBP) which has significant relevance in real-world Assembly Line settings. SDALBP extends the basic problem by considering sequence-dependent task times. In this paper, we define this new problem, formulate several versions of a mixed-integer program, adapt solution approaches for SALBP to SDALBP, generate test data and perform some preliminary computational experiments. As a main result, we find that applying SALBP-based search procedures is very effective, whereas modelling and solving the problem with MIP standard software is not recommendable.
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a survey on problems and methods in generalized Assembly Line Balancing
European Journal of Operational Research, 2006Co-Authors: Christian Becker, Armin SchollAbstract:Abstract Assembly Lines are traditional and still attractive means of mass and large-scale series production. Since the early times of Henry Ford several developments took place which changed Assembly Lines from strictly paced and straight single-model Lines to more flexible systems including, among others, Lines with parallel work stations or tasks, customer-oriented mixed-model and multi-model Lines, U-shaped Lines as well as unpaced Lines with intermediate buffers. In any case, an important decision problem, called Assembly Line Balancing problem, arises and has to be solved when (re-) configuring an Assembly Line. It consists of distributing the total workload for manufacturing any unit of the product to be assembled among the work stations along the Line. Assembly Line Balancing research has traditionally focused on the simple Assembly Line Balancing problem (SALBP) which has some restricting assumptions. Recently, a lot of research work has been done in order to describe and solve more realistic generalized problems (GALBP). In this paper, we survey the developments in GALBP research.
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the sequence dependent Assembly Line Balancing problem
Jenaer Schriften zur Wirtschaftswissenschaft (Expired!), 2006Co-Authors: Armin Scholl, Nils Boysen, Malte FliednerAbstract:The sequence-dependent Assembly Line Balancing problem Abstract Assembly Line Balancing problems (ALBP) arise whenever an Assembly Line is configured, redesigned or adjusted. An ALBP consists of distributing the total workload for manufacturing any unit of the products to be assembled among the work stations along the Line. The sequence-dependent Assembly Line Balancing problem (SDALBP) is an extension of the standard simple Assembly Line Balancing problem (SALBP) which has significant relevance in realworld Assembly Line settings. SDALBP extends the basic problem by considering sequencedependent task times. In this paper, we define this new problem, formulate several versions of a mixed-integer program, adapt solution approaches for SALBP to SDALBP, generate test data and perform some preliminary computational experiments. As a main result, we find that applying SALBP-based search procedures is very effective, whereas modeling and solving the problem with MIP standard software is not recommendable.
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a classification of Assembly Line Balancing problems
Jenaer Schriften zur Wirtschaftswissenschaft (Expired!), 2006Co-Authors: Nils Boysen, Malte Fliedner, Armin SchollAbstract:Assembly Lines are special flow-Line production systems which are of great importance in the indus-trial production of high quantity standardized commodities. Recently, Assembly Lines even gained importance in low volume production of customized products (mass-customization). Due to high capital requirements when installing or redesigning a Line, its configuration planning is of great rele-vance for practitioners. Accordingly, this attracted attention of plenty researchers, who tried to sup-port real-world configuration planning by suited optimization models (Assembly Line Balancing prob-lems). In spite of the enormous academic effort in Assembly Line Balancing, there remains a consider-able gap between requirements of real configuration problems and the status of research. To ease communication between researchers and practitioners, we provide a classification scheme of assem-bly Line Balancing. This is a valuable step in identifying remaining research challenges which might contribute to closing the gap.
Malte Fliedner - One of the best experts on this subject based on the ideXlab platform.
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A classification of Assembly Line Balancing problems
European Journal of Operational Research, 2007Co-Authors: Nils Boysen, Malte Fliedner, Armin SchollAbstract:Assembly Lines are special flow-Line production systems which are of great importance in the industrial production of high quantity standardized commodities. Recently, Assembly Lines even gained importance in low volume production of customized products (mass-customization). Due to high capital requirements when installing or redesigning a Line, its configuration planning is of great relevance for practitioners. Accordingly, this attracted attention of many researchers, who tried to support real-world configuration planning by suited optimization models (Assembly Line Balancing problems). In spite of the enormous academic effort in Assembly Line Balancing, there remains a considerable gap between requirements of real configuration problems and the status of research. To ease communication between researchers and practitioners, we provide a classification scheme of Assembly Line Balancing. This is a valuable step in identifying remaining research challenges which might contribute to closing the gap.
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The sequence-dependent Assembly Line Balancing problem
OR Spectrum, 2006Co-Authors: Armin Scholl, Nils Boysen, Malte FliednerAbstract:Assembly Line Balancing problems (ALBP) arise whenever an Assembly Line is configured, redesigned or adjusted. An ALBP consists of distributing the total workload for manufacturing any unit of the products to be assembled among the work stations along the Line. The sequence-dependent Assembly Line Balancing problem (SDALBP) is an extension of the standard simple Assembly Line Balancing problem (SALBP) which has significant relevance in real-world Assembly Line settings. SDALBP extends the basic problem by considering sequence-dependent task times. In this paper, we define this new problem, formulate several versions of a mixed-integer program, adapt solution approaches for SALBP to SDALBP, generate test data and perform some preliminary computational experiments. As a main result, we find that applying SALBP-based search procedures is very effective, whereas modelling and solving the problem with MIP standard software is not recommendable.
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the sequence dependent Assembly Line Balancing problem
Jenaer Schriften zur Wirtschaftswissenschaft (Expired!), 2006Co-Authors: Armin Scholl, Nils Boysen, Malte FliednerAbstract:The sequence-dependent Assembly Line Balancing problem Abstract Assembly Line Balancing problems (ALBP) arise whenever an Assembly Line is configured, redesigned or adjusted. An ALBP consists of distributing the total workload for manufacturing any unit of the products to be assembled among the work stations along the Line. The sequence-dependent Assembly Line Balancing problem (SDALBP) is an extension of the standard simple Assembly Line Balancing problem (SALBP) which has significant relevance in realworld Assembly Line settings. SDALBP extends the basic problem by considering sequencedependent task times. In this paper, we define this new problem, formulate several versions of a mixed-integer program, adapt solution approaches for SALBP to SDALBP, generate test data and perform some preliminary computational experiments. As a main result, we find that applying SALBP-based search procedures is very effective, whereas modeling and solving the problem with MIP standard software is not recommendable.
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a classification of Assembly Line Balancing problems
Jenaer Schriften zur Wirtschaftswissenschaft (Expired!), 2006Co-Authors: Nils Boysen, Malte Fliedner, Armin SchollAbstract:Assembly Lines are special flow-Line production systems which are of great importance in the indus-trial production of high quantity standardized commodities. Recently, Assembly Lines even gained importance in low volume production of customized products (mass-customization). Due to high capital requirements when installing or redesigning a Line, its configuration planning is of great rele-vance for practitioners. Accordingly, this attracted attention of plenty researchers, who tried to sup-port real-world configuration planning by suited optimization models (Assembly Line Balancing prob-lems). In spite of the enormous academic effort in Assembly Line Balancing, there remains a consider-able gap between requirements of real configuration problems and the status of research. To ease communication between researchers and practitioners, we provide a classification scheme of assem-bly Line Balancing. This is a valuable step in identifying remaining research challenges which might contribute to closing the gap.
Alberto Portioli-staudacher - One of the best experts on this subject based on the ideXlab platform.
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Integrating inspection-policy design in Assembly-Line Balancing
International Journal of Production Research, 2006Co-Authors: Omar Egidio Carcano, Alberto Portioli-staudacherAbstract:This paper addresses the problem of Assembly-Line Balancing and selection of the best inspection policy. Different inspection policies yield different manufacturing, reworking, inspection, and external failure costs. While, in the literature, Assembly-Line Balancing and inspection-policy design have usually been addressed as different problems, they are strongly interrelated. Inspection tests require time to be carried out, and thus their assignation directly influences the results of the Assembly-Line Balancing procedure, that is the number of stations that are necessary and hence the Line installation cost. Thus, the advantages of integrating inspection policy design in Assembly-Line Balancing are clear, but to our knowledge no such model is available yet. In this paper, a new model that simultaneously defines inspection policy and Assembly-Line Balancing is presented.
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(18th ICPR) INTEGRATING INSPECTION POLICY DESIGN IN Assembly Line Balancing
International Journal of Production Research, 2006Co-Authors: Omar Egidio Carcano, Alberto Portioli-staudacherAbstract:This paper addresses the problem of Assembly Line Balancing and selection of the best inspection policy. Different inspection policies yield different manufacturing, reworking, inspection and external failure costs. While in literature Assembly Line Balancing and inspection policy design have usually been addressed as different problems, they are strongly interrelated. Inspection tests requires time to be performed and thus their assignation directly influences the results of the Assembly Line Balancing procedure, that is the number of stations that are necessary and hence the Line installation cost. Provided what said above, the advantage of integrating inspection policy design in Assembly Line Balancing appears clear, but to our knowledge there is not such a model yet. In this paper a new model that defines simultaneously inspection policy and Assembly Line Balancing is presented.
Liliana Capacho - One of the best experts on this subject based on the ideXlab platform.
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ASALBP: The Alternative Subgraphs Assembly Line Balancing Problem
International Journal of Production Research, 2008Co-Authors: Liliana Capacho, Rafael PastorAbstract:Assembly Line Balancing problems basically consist in assigning a set of tasks to a group of workstations while maintaining the tasks' precedence relations, which are represented by a predetermined precedence graph. However, one or more parts of a product's Assembly process may admit alternative precedence subgraphs, which represent possible Assembly variants. In general, because of the great difficulty of the problem and the impossibility of representing alternative subgraphs in a precedence graph, the system designer will decide to select, a priori, one of such alternative subgraphs. This paper presents, characterizes and formulates a new general Assembly Line Balancing problem with practical relevance: the Alternative Subgraphs Assembly Line Balancing Problem (ASALBP). Its novel characteristic is that it considers the possibility of having alternative Assembly subgraphs, with the processing times and/or the precedence relations of certain tasks dependent on the Assembly subgraph selected. Therefore, solving this problem implies simultaneously selecting an Assembly subgraph for each part of the Assembly that allows alternatives and Balancing the Line. The potentially positive effects of this on the solution of the problem are shown in a numerical example. Finally, a simple mathematical programming model is described and the results of a brief computational experiment are presented.
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ASALBP: the alternative subgraphs Assembly Line Balancing problem
International Journal of Production Research, 2008Co-Authors: Liliana Capacho, Rafael PastorAbstract:Assembly Line Balancing problems basically consist of assigning a set of tasks to a group of workstations while maintaining the tasks’ precedence relations, which are represented by a predetermined precedence graph. However, one or more parts of a product's Assembly process may admit alternative precedence subgraphs, which represent possible Assembly variants. In general, because of the great difficulty of the problem and the impossibility of representing alternative subgraphs in a precedence graph, the system designer will decide to select, a priori, one of such alternative subgraphs. This paper presents, characterizes and formulates a new general Assembly Line Balancing problem with practical relevance: the alternative subgraphs Assembly Line Balancing problem (ASALBP). Its novel characteristic is that it considers the possibility of having alternative Assembly subgraphs, with the processing times and/or the precedence relations of certain tasks dependent on the Assembly subgraph selected. Therefore, so...
