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Found 6273 publications

Investigation of the spatial distribution algorithm of the traffic flow analysis and of the entity flow-phase analysis

László Muka Gábor Lencse

Publication Name: Esm 2007 2007 European Simulation and Modelling Conference Modelling and Simulation 2007

Publication Date: 2007-01-01

Volume: Unknown

Issue: Unknown

Page Range: 291-295

Description:

This paper investigates an important algorithm that is used in both the Traffic-Flow Analysis and the Entity Flow-phase Analysis. These methods are similar to each other and can be used for the fast and approximate (performance) analysis of Information and Communication Technology (ICT) systems and Business Process (BP) systems. Both methods contain an algorithm for the spatial distribution of the traffic (or entities) in the system. It is shown how the error of the spatial distribution can be measured, and the effect of the so called size of routing unit parameter of two algorithms is investigated.

Open Access: Yes

DOI: DOI not available

Combination and interworking of four modelling methods for infocommunications and business process systems

László Muka Gábor Lencse

Publication Name: 5th International Industrial Simulation Conference 2007 Isc 2007

Publication Date: 2007-01-01

Volume: Unknown

Issue: Unknown

Page Range: 350-354

Description:

This paper describes how we can use four modelling methods together. We model Information and Communication Technology (ICT) systems and Business Process (BP) systems. The aim of the modelling is to experiment with the models, that is, simulation. Two of the methods are the detailed modelling of the ICT and of the BP systems, as we usually do that for discrete event simulation. The other two methods are those that enable us to make rapid performance analysis of these systems, namely Traffic-Flow Analysis (TEA) for ICT systems and Entity Flow-phase Analysis (EFA) for BP systems. The solutions for the combination and interworking of these methods are described.

Open Access: Yes

DOI: DOI not available

Resource allocation and its distributed implementation

Szabolcs Póta Zs T. Kosztyán Bencsik Andrea

Publication Name: Innovations and Advanced Techniques in Computer and Information Sciences and Engineering

Publication Date: 2007-01-01

Volume: Unknown

Issue: Unknown

Page Range: 511-518

Description:

During the execution of a project (investment, innovation etc.), three important parameters must be kept in mind: we have to execute the project as soon as possible, with minimal total cost and not to exceed resource (manpower, materials, engines etc.) availabilities. Why does it important to execute the project as soon as possible with minimal total cost? If more than one company compete for the execution of an investment project, usually the chance of winning the tender will be higher if a company can execute the project with minimal total project time (TPT) and minimal total project cost. This problem could already be handled in the 60s and 70s with network planning (CPM, MPM, PERT etc.), scheduling (Gantt Diagrams, LOB etc.) and other related cost-minimizing (CPM/COST, MPM/COST etc.) techniques. The most difficult problem was to handle the resources. During the execution of a project we must keep in view the resources, because these resources are usually straitened. There are well-defined number of labours, engines and so on. If we would like to execute the project with minimal TPT and minimal total project cost and optimal use of the resources (manpower, materials, engines etc.) the problem becomes easily so hard to solve (already at 5000-10000 activities) that computers available today cannot find the solution within a reasonable time. The real problem is more complicated, because before the execution of the project we can only estimate the duration time, (variable) cost and resource need of activities. In real life it is common that the duration time of project activities cannot be estimated correctly. In this paper a novel algorithm is introduced by which an optimal resource allocation with minimal total cost for any arbitrary project could be determined. Moreover, this algorithm also handles the competences of the human resources. A distributed problem solving environment is also introduced that implements the above mentioned optimal resource allocation algorithm with a parallel branch and bound method. The system is built on the Jini technology [44]. It is a dynamic, service-oriented infrastructure that utilizes spare cycles of networked workstations in an efficient way and solves computation intensive problems more easily due to the parallelization. © 2007 Springer.

Open Access: Yes

DOI: 10.1007/978-1-4020-6268-1_90

Takagi-sugeno fuzzy control models for large scale logistics systems

Gabriella Orbán István Harmati Peter Varlaki

Publication Name: Isciii 07 3rd International Symposium on Computational Intelligence and Intelligent Informatics Proceedings

Publication Date: 2007-01-01

Volume: Unknown

Issue: Unknown

Page Range: 199-203

Description:

Requirements, such as adaptive behavior, learning ability and self regulative features, that have to be met by modern logistic systems, need the construction of such control systems that are able to control the basic processes and also to develop and improve the material and information system by automating the control processes. For controlling the logistical systems the papers propose the application of LPV structure by which non-linear systems can be controlled on the basis of linear control theories. The proposal points out that the priorities of different states are of great importance when generating the logical rules of operation. For resolving the difficulties of constructing mathematical algorithms fuzzy sets are suggested, so in the control model a Takagi-Sugeno solution is proposed, that can describe multi-input multi-output, non-linear, dynamic systems like logistical systems. © 2007 IEEE.

Open Access: Yes

DOI: 10.1109/ISCIII.2007.367389

Effects of information technology investments on the efficiency of logistic processes

Gabriella Orbán

Publication Name: 14th World Congress on Intelligent Transport Systems ITS 2007

Publication Date: 2007-01-01

Volume: 7

Issue: Unknown

Page Range: 5238-5248

Description:

The output of logistics is performed by the appropriate and proportional use of material and information flows. Important issue is to determine the proper equilibrium between the resources devoted to the two main system elements. The necessity of continuous improvement of informatics and logistic flows is not questionable since the efficiency of logistics control systems can be increased by reducing the time gap between the time of gaining the data and use of information for planning purpose. In different logistics subsystems the role and importance of time gaps differ. Having generally overviewed the subsystems the papers introduce the efficiency of informatics based on Cobb-Douglas production function in order to spot the elements of logistics where the reduction of time gap is of economic interest, that is under what conditions can the IT developments and investment be efficient. Finally a draft framework is described as a general solution that can use informatic means in order to increase road transport system capacity usage.

Open Access: Yes

DOI: DOI not available

Estimation of energy distribution for car-body deformation

István Harmati Peter Varlaki

Publication Name: Isciii 07 3rd International Symposium on Computational Intelligence and Intelligent Informatics Proceedings

Publication Date: 2007-01-01

Volume: Unknown

Issue: Unknown

Page Range: 229-232

Description:

Identification of distribution of deformational energy for vehicle body deformational processes is a very important and difficult task in accident analysis and in safety car-body design. Exact estimation or measuring of the absorbed energy by the deformation is almost impossible, so we apply an estimation for this. The classical tool for this task is usually a differental equation based finite element method, which requires exact knowledge about the parameters. In the following we introduce a simple numerical model describing the changing of the energy distribution during the whole deformational process. The main idea is similar to a finite element method: let have a 3D rectangular grid on the car-body, according to the energy absorbing properties of the vehicle, so each cell is approximately homogenous. For For each cell a monotonous decreasing function is assigned, which describes approximately the rate of the absorbed and the input energy. For different possible directions of the impact we define different absorbing functions, and instead of the original input, we deal with its orthogonal components, so the final result then will be the sum of the particular result. © 2007 IEEE.

Open Access: Yes

DOI: 10.1109/ISCIII.2007.367394

Evaluation of steel hardenability by JM®-test

D. Iljkic N. Tomasic G. E. Totten B. Smoljan Imre Felde Tamás Réti

Publication Name: Materials Science Forum

Publication Date: 2007-01-01

Volume: 537-538

Issue: Unknown

Page Range: 607-614

Description:

The modified Jominy-test was designed for prediction of hardenability of high-hardenability tool steels and possibility of application of modified Jominy-test in computer simulation of quenching of high-hardenability tool steels has been investigated. Because of high hardenability there are limits in application of original Jominy-specimen in simulation of quenching of steels. The performance of investigated modified Jominy-test in simulation of quenching of high-hardenability tool steels was estimated by comparison of cooling curves of modified Jominy-specimen (JM®-specimen) and cylindrical specimen. The influence of dimension of JM®-specimen on cooling curves has been investigated. The time of cooling, t8/5 relevant for results of quenching was predicted. Modified Jominy-test can be applied in simulation of quenching of steel with higher hardenability rather than original Jominy-test.

Open Access: Yes

DOI: 10.4028/0-87849-426-x.607

Practice-related problems and solutions on the field of improving worker satisfaction

Bencsik Andrea Zsuzsanna Nagy

Publication Name: Problems and Perspectives in Management

Publication Date: 2007-01-01

Volume: 5

Issue: 3

Page Range: 58-68

Description:

The economic life has been investigating for decades the question of by what kind of activity, by the control of which factors can an enterprise be successful. As a consequence of the economic development and the informational boom, the hard factors, the purchasable and money-dependent systems and resources are accessible for everyone, therefore they have ceased to compose competitive advantages i.e. discriminative success factors. Consequently, the attention have turned towards the soft, human factors. Now we know that for the success the harmonious co-operation of both sides is needed. It was exactly for the practical adaptation of this approach why the European Foundation for Quality Management called the EFQM self-assessment model into being as the basis of quality awards. It unites in one model the factors of the successful business operation and helps the organizational self-improvement by its self-assessment method. The operation of the method, however, is frequently impeded by problems which are caused by exactly the difficult handling of the previously mentioned soft factors in practice. For the sake of successful operation, a solution for these problems must be found. During our research we conducted a primary investigation, having regard to the Hungarian peculiarities, among those Hungarian-owned companies which competed for the National Quality Award. In the course of the investigation we examined their organizational processes according to the factors of the EFQM, although mainly concentrating on the working methods and mechanisms, not on results. Comparing the individual case studies we have obtained the conclusion that, among the soft factors, job satisfaction at the Hungarian-owned companies does not follow the EFQM's viewpoint on self-improvement. Therefore, after a brief theoretical review of the EFQM model and one of its elements, job satisfaction, and through an example which is relevant from the view of the handling of satisfaction, we present the satisfaction-improvement method which we developed by observing the results of the primary investigation. © Andrea Bencsik, Zsuzsanna Nagy, 2007.

Open Access: Yes

DOI: DOI not available

Component based hardware-software system for fuzzy controlling of automated vehicles

A. Geresdi L. Siroki T. Pápai László T. Kóczy

Publication Name: Proceedings of Sefi and Igip Joint Annual Conference 2007 Joining Forces in Engineering Educations Towards Excellence

Publication Date: 2007-01-01

Volume: Unknown

Issue: Unknown

Page Range: 397-398

Description:

No description provided

Open Access: Yes

DOI: DOI not available