Browsing by Subject "multi-agent systems"

Now showing 1 - 12 of 12

Access status: Open Access ,
Agent-based data integration framework
(Wydawnictwa AGH, 2014) Faber, Łukasz
Combining data from diverse, heterogeneous sources while facilitating a unified access to it is an important (albeit difficult) task. There are various possibilities of performing it. In this publication, we propose and describe an agent-based framework dedicated to acquiring and processing distributed, heterogeneous data collected from diverse sources (e.g., the Internet, external software, relational, and document databases). Using this multi-agent-based approach in the aspects of the general architecture (the organization and management of the framework), we create a proof-of-concept implementation. The approach is presented using a sample scenario in which the system is used to search for personal and professional profiles of scientists.
Access status: Open Access ,
Agentowo-ewolucyjna platforma obliczeń optymalizacyjnych
(Wydawnictwa AGH, 2009) Nawarecki, Edward; Siwik, Leszek
Against the general idea of realization of virtual agent systems, condensed description of intelligent computational platform dedicated for solving complex multiobjective optimization problems is presented. As an illustration a selected results of experiments are also presented.
Access status: Open Access ,
Agentowy model systemu logistycznego
(Wydawnictwa AGH, 2009) Nawarecki, Edward; Koźlak, Jarosław
In the paper a concept of methodology fot development of Multi-agent systems for modelling and optimising supply chains is presented. The example of a pilot realisation of the system and examples of experimental results are shown.
Access status: Open Access ,
Evolutionary multi-agent computing in inverse problem
(Wydawnictwa AGH, 2013) Wróbel, Krzysztof; Torba, Paweł; Paszyński, Maciej; Byrski, Aleksander
This paper tackles the application of evolutionary multi-agent computing to solve inverse problems. High costs of fitness function call become a major difficulty when approaching these problems with population-based heuristics. However, evolutionary agent-based systems (EMAS) turn out to reduce the fitness function calls, which makes them a possible weapon of choice against them. This paper recalls the basics of EMAS and describes the considered problem (Step and Flash Imprint Lithography), and later, shows convincing results that EMAS is more effective than a classical evolutionary algorithm.
Access status: Open Access ,
Evolutionary multi-agent systems in non-stationary environments
(Wydawnictwa AGH, 2013) Kisiel-Dorohinicki, Marek
In this article, the performance of an evolutionary multi-agent system in dynamic optimization is evaluated in comparison to classical evolutionary algorithms. The starting point is a general introduction describing the background, structure and behavior of EMAS against classical evolutionary techniques. Then, the properties of energy-based selection are investigated to show how they may influence the diversity of the population in EMAS. The considerations are illustrated by experimental results based on the dynamic version of the well-known, high-dimensional Rastrigin function benchmark.
Access status: Open Access ,
Koncepcja holonicznego systemu do zarządzania łańcuchami dostaw
(Wydawnictwa AGH, 2011) Koźlak, Jarosław; Żabińska-Rakoczy, Małgorzata
In the paper, the concept of a holonic multi-agent system for modelling and optimising market strategies for a company and management of supply chains is presented. The measures which describe the situation of the company in the market, used for the choice of activity strategies, and especially decisions of assigning long-term contracts and holon formation consisting of cooperated companies are discussed.
Access status: Open Access ,
Koncepcja zastosowania podejścia agentowego w systemach SOA
(Wydawnictwa AGH, 2009) Cetnarowicz, Krzysztof; Dyduch, Tadeusz; Koźlak, Jarosław; Żabińska-Rakoczy, Małgorzata
In the paper, an overview of the research domain as well as tools related to development of SOA systems based on automatic composition of Web Services is presented. The concept of applying multi-agent approach in such systems and a project of its architecture are given. The domains of implemented pilot realisations are shown.
Access status: Open Access ,
Modelowanie anomalii i kryzysów w systemach zdecentralizowanych
(Wydawnictwa AGH, 2007) Dobrowolski, Grzegorz; Koźlak, Jarosław; Nawarecki, Edward
In this paper examples of the application of a multi-agent approach are given for modelling and the optimising of handling anomalies and crisis situations within the scope of supply chains and city traffic. The system for modelling supply chains takes into consideration auctions led among contractors and prestige parameter which describes the relationships among the pairs of companies. The system for modelling city traffic is based on the concept of cellular automaton and an algorithm of rotating discs responsible for the traffic lights configuration.
Access status: Open Access ,
Niching in evolutionary multi-agent systems
(Wydawnictwa AGH, 2013) Krzywicki, Daniel
Niching is a group of techniques used in evolutionary algorithms, useful in several types of problems, including multimodal or nonstationary optimization. This paper investigates the applicability of these methods to evolutionary multi-agent systems (EMAS), a hybrid model combining the advantages of evolutionary algorithms and multi-agent systems. This could increase the efficiency of this type of algorithms and allow to apply them to a wider class of problems. As a starting point, a simple but flexible EMAS framework is proposed. Then, it is shown how to extend this framework in order to introduce niching, by adapting two classical niching methods. Finally, preliminary experimental results show the efficiency and the simultaneous discovery of multiple optima by this modified EMAS.
Access status: Open Access ,
Problem integralności funkcjonalnej pewnej klasy systemów wieloagentowych
(Wydawnictwa AGH, 1999) Cetnarowicz, Krzysztof
Multi-agent systems have many advantages and give numerous new possibilities in creation of information systems. However many problems related to functioning of the systems are still unsolved. Functional integrity of multi-agent systems belongs to such problems. Functional integrity of multi-agent systems may be defined in general as preservation of basic functions of the system during its functioning. Functional integrity may be analyzed from the point of view of different functions of the system (the functions that should be preserved) and also from the point of view of various factors that may influence the loss or preservation of functional integrity of the system. The paper deals with examination of functional integrity of multi-agent system depending upon number of agents (global and of particular types). During system work, agents generate agents of the same or different type that depend on their possibilities and system needs. The process performed without use of appropriate control mechanisms may lead to excessive (blocking of the system) or too little number of agents and even lack of agents (disappearance of the functions of a system that are performed by a gents of a certain type). A proposal of functional integrity phenomenon analysis of multi-agent systems that is related to the number of agents in their population and a proposal of mechanisms that enable maintenance of functional integrity, in particular a concept of the so-call ed »free agents« have been presented in the paper. Consideration has been carried out on the basis of simulation examination of some elass of multi-agent systems. Results of simulation of proposed Solutions have been included in the work.
Access status: Open Access ,
Rozwiązywanie problemów transportowych wykorzystujące metody identyfikacji wzorców sytuacyjnych
(Wydawnictwa AGH, 2011) Koźlak, Jarosław; Pisarski, Sebastian; Żabińska-Rakoczy, Małgorzata
The goal of the work is to design algorithms to solve transportation problem - pickup and delivery problem with time windows. The import element of the solution is to calculate measures which describe the current situation from the point of view of vehicle position as well as the spatial and temporal locations of transportation requests and the choice of the suitable version and configuration of the optimisation algorithm taking into consideration values of these measures. It makes it possible to use the algorithm which offers the best solution for the given kind of the data and to limit the computation time.
Access status: Open Access ,
Rozwiązywanie problemów transportowych za pomocą agentów
(Wydawnictwa AGH, 2009) Koźlak, Jarosław; Żabińska-Rakoczy, Małgorzata
In the paper, the system based on the concept of holons, which solves transportation problems has been presented. The proposed system has enabled to compare the quality of solutions offered by classic algorithms for widely known and applied test problems. These problems have been modified to take into consideration potential crisis situations as well as possibilities given by the use of holonic approach.