Performance aspects of a Lagrangian relaxation based heuristic for solving large 0-1 integer linear programs are discussed. In particular, we look at its application to airline and railway crew scheduling problems. We...
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ISBN:
(纸本)3540658211
Performance aspects of a Lagrangian relaxation based heuristic for solving large 0-1 integer linear programs are discussed. In particular, we look at its application to airline and railway crew scheduling problems. We present a scalable parallelization of the original algorithm used in production at Carmen Systems AB, Goteborg, Sweden, based on distributing the variables and a new sequential active set strategy which requires less work and is better adapted to the memory hierachy properties of modern RISC processors. the active set strategy can even be parallelized on networks of workstations.
System modeling is high relevant in the automation and simulation processes. Until now, there have been two main ways to face the problem. the first is to collect the equations, normally differential, which direct the...
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System modeling is high relevant in the automation and simulation processes. Until now, there have been two main ways to face the problem. the first is to collect the equations, normally differential, which direct the dynamics of the system and to solve them using, most of the time, the S transform. the other way is to collect enough data from the process, and, based on a predefined structure of the model, use a method for the parameter adjustment such as least mean square technique. In this paper an alternative method is presented. Based on a recent technique like Genetic programming, a particular application of Genetic Algorithms where the structures under adaptation are `computer programs', a tray for the induction of models in the block diagram representation using simple discretized systems is made. the genetic program needs a way of performing parameter adjustment. For this purpose, a Genetic Algorithm has been applied with highly convincing results.
the purpose of the paper is to propose a simple experimental method to evaluate the execution time in programmable controllers. First, features of the cyclic scan are examined experimentally by fundamental programs fo...
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the purpose of the paper is to propose a simple experimental method to evaluate the execution time in programmable controllers. First, features of the cyclic scan are examined experimentally by fundamental programs for evaluation. Second, the experimental evaluation method of the execution time of LDs and SFCs using stochastic tests is established. Furthermore, discussions on the evaluation method of other functions, the design for programming, and application to the real systems are also given.
the PLC programming is designed for a medium user of this equipment. Hence, object-oriented qualities can not be created in the same way established for higher languages like the C++, Java, Eiffel. However, they shoul...
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the PLC programming is designed for a medium user of this equipment. Hence, object-oriented qualities can not be created in the same way established for higher languages like the C++, Java, Eiffel. However, they should fulfil the theoretical principles that govern them. In ALS 4.0 programming language a hierarchy of classes is set in three big trees which include the areas of application of this equipment. Its data and functions are encapsulated withthree degrees of visibility (private, protected and public). the dynamic pass of types in execution time is allowed. Persistence is guaranteed outside the creation place and separated from ancestors using the macronets library. However, the whole normalized syntax of the structured languages of the IEC 61131-3 is almost kept. Only the use of object-oriented advantages adapted to the simple level of the standard PLC programming languages will permit the wide diffusion of their features among the PLC users. ALS 4.0 achieves this combination.
We study the facial structure of a polyhedron associated withthe single node relaxation of network flow problems with additive variable upper bounds. this type of structure arises, for example, in network design/expa...
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作者：
Sebo, ACNRS
Lab Leibniz IMAG Grenoble France Kyoto Univ
Math Sci Res Inst Kyoto 60601 Japan
We study simplices whose vertices lie on a lattice and have no other lattice points. Such 'empty lattice simplices' come up in the theory of integer programming, and in some combinatorial problems. they have b...
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ISBN:
(纸本)3540660194
We study simplices whose vertices lie on a lattice and have no other lattice points. Such 'empty lattice simplices' come up in the theory of integer programming, and in some combinatorial problems. they have been investigated in various contexts and under varying terminology by Reeve, White, Scarf, Kannan and Lovasz, Reznick, Kantor, Naase and Ziegler, etc. Can the 'emptiness' of lattice simplices be 'well-characterized' ? Is their 'lattice-width' small ? Do the integer points of the parallelepiped they generate have a particular structure ? the 'good characterization' of empty lattice simplices occurs to be open in general ! We provide a polynomial algorithm for deciding when a given integer 'knapsack' or 'partition' lattice simplex is empty. More generally, we ask for a characterization of linear inequalities satisfied by the lattice points of a lattice parallelepiped. We state a conjecture about such inequalities, prove it for n less than or equal to 4, and deduce several variants of classical results of Reeve, White and Scarf characterizing the emptiness of small dimensional lattice simplices. For instance, a three dimensional integer simplex is empty if and only if all its faces have width 1. Seemingly different characterizations can be easily proved from one another using the Hermite normal form. In fixed dimension the width of polytopes can be computed in polynomial time (see the simple integer programming formulation of Naase and Ziegler). We prove that it is already NP-complete to decide whether the width of a very special class of integer simplices is 1, and we also provide for every n greater than or equal to 3 a simple example of n-dimensional empty integer simplices of width n - 2, improving on earlier bounds.
Production plants have been complicated by the diversification of products. In order to control complicated production plants, the distributed process control is one of powerful approach. In the development of a distr...
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Production plants have been complicated by the diversification of products. In order to control complicated production plants, the distributed process control is one of powerful approach. In the development of a distributed process control system, it is difficult to develop its software because distributed controllers complicatedly interact with each other. For that reason, the function block model, that is the specification language for distributed process control logic, is being standardized in IEC61499-1. In this paper, a distributed process control programming tool for function block description is proposed. It is possible to describe control programs hierarchically by using function blocks. the GUI of this tool supplies multi-windows which can simultaneously display function blocks on different hierarchical levels. In this tool, inputted programs can also be verified by a simulation. this tool is applied to the control program description of an automatic carrier system. It has been confirmed that the control program is completely described and simulated by using this tool.
When decoding a threshold phenomenon is often observed: decoding deteriorates very suddenly around some critical value of the channel parameter. threshold behaviour has been studied in many situations outside coding t...
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the proceedings contain 53 papers. the special focus in this conference is on Adaptation of System Actions, Constructing User Models Explicitly, Building User Models Unobtrusively and Managing User Models. the topics ...
ISBN:
(纸本)9783211831519
the proceedings contain 53 papers. the special focus in this conference is on Adaptation of System Actions, Constructing User Models Explicitly, Building User Models Unobtrusively and Managing User Models. the topics include: the application of user modeling techniques to reason about the human contribution to major accidents;using plan recognition in human-computer collaboration;tailoring the interaction with users in electronic shops;empirically evaluating an adaptable spoken dialogue system;user modeling in the design of interactive interface agents;modeling the social practices of users in internet communities;the development of behavior-based user models for a computer system;analyzing and modeling web query refinement;building user and expert models by long-term observation of application usage;strategy support of algebraic expression writing;exploiting learning techniques for the acquisition of user stereotypes and communities;machine learning and knowledge representation in the labour approach to user modeling;a computational architecture for conversation;learning models of other agents u sing influence diagrams;interpreting symptoms of cognitive load in speech input;an application-lndependent intelligent user support system exploiting action-sequence based user modelling;the emergence of student models from an analysis of ethical decision making in a scenario-based learning environment;a collaborative approach to user modeling within a multi-functional architecture;a student model to assess self-explanation while learning from examples and modeling cognition-emotion of users for improved interaction with software systems.
Production plants have been complicated by the diversification of products. In order to control complicated production plants, distributed process control is a powerful approach. In the development of a distributed pr...
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Production plants have been complicated by the diversification of products. In order to control complicated production plants, distributed process control is a powerful approach. In the development of a distributed process control system, it is difficult to develop its software because distributed controllers complicatedly interact with each other. For that reason, the function block model, which is the specification language for distributed process control logic, is being standardized in IEC61499-1. A distributed process control programming tool for function block description is proposed. It is possible to describe control programs hierarchically by using function blocks. the GUI of this tool supplies multi-windows which can simultaneously display function blocks on different hierarchical levels. In this tool, inputted programs can also be verified by a simulation. this tool is applied to the control program description of an automatic carrier system. It has been confirmed that the control program is completely described and simulated by using this tool.
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