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1

Application of information technologies in optimization of the machine state evaluation process

Wilczarska J.

Journal of Polish CIMAC

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2014

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Vol. 9, no 3

111--120

EN

The use of information technologies in machine diagnostics allows to optimize the process of the machine state evaluation. Information technologies are tools used to support the machine technical state. There is a need to do more research into these technologies and continue to develop them as they provide methods for the process optimization. Multiple criteria optimization methods often find application in selection of a set of diagnostic parameters to be further used for assessment of a machine state. This study deals with the properties and possibilities of OPTIMUS software used for the optimization process.

2

Reference distribution based decision support platform

Breja K., Ogryczak W.

Journal of Telecommunications and Information Technology

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2008

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nr 3

5-14

EN

There many decision problems where numerous partial achievement functions are considered impartially which makes the distribution of achievements more important than the assignment of several achievements to the specific criteria. Such models are generally related to the evaluation and optimization of various systems which serve many users where quality of service for every individual user defines the criteria. This applies to various technical systems, like to telecommunication ones among others, as well as to social systems. An example arises in location theory, where the clients of a system are entitled to equal treatment according to some community regulations. This paper presents an implementation of decision support framework for such problems. This platform is designed for multiple criteria problems analyzed with the reference distribution approach. Reference distribution approach is an extension of the reference point method.

3

Multicriteria models for fair resource allocation

Ogryczak W.

Control and Cybernetics

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2007

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Vol. 36, no 2

303-332

EN

Resource allocation problems are concerned with the allocation of limited resources among competing activities so as to achieve the best performances. However, in systems which serve many users there is a need to respect some fairness rules while looking for the overall efficiency. The so-called Max-Min Fairness is widely used to meet these goals. However, allocating the resource to optimize the worst performance may cause dramatic worsening of the overall system efficiency. Therefore, several other fair allocation schemes are being considered and analyzed. In this paper we show how the concepts of multiple criteria equitable optimization can effectively be used to generate various fair and efficient allocation schemes. First, we demonstrate how the scalar inequality measures can be consistently used in bicriteria models to search for fair and efficient allocations. Further, two alternative multiple criteria models equivalent to equitable optimization are introduced, thus allowing to generate a larger variety of fair and efficient resource allocation schemes.

4

Fair and efficient network dimensioning with the reference point methodology

Goryczak W., Wierzbicki A., Milewski M.

Journal of Telecommunications and Information Technology

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2006

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nr 4

21-30

EN

The dimensioning of telecommunication networks that carry elastic traffic requires the fulfillment of two conflicting goals: maximizing the total network throughput and providing fairness to all flows. Fairness in telecommunication network design is usually provided using the so-called max-min fairness (MMF) approach. However, this approach maximizes the performance of the worst (most expensive) flows which may cause a large worsening of the overall throughput of the network. In this paper we show how the concepts of multiple criteria equitable optimization can be effectively used to generate various fair and efficient allocation schemes. We introduce a multiple criteria model equivalent to equitable optimization and we develop a corresponding reference point procedure for fair and efficient network dimensioning for elastic flows. The procedure is tested on a sample network dimensioning problem for elastic traffic and its abilities to model various preferences are demonstrated.

5

On multi-criteria approaches to bandwidth allocation

Ogryczak W., Wierzbicki A.

Control and Cybernetics

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2004

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Vol. 33, no 3

427-448

EN

Modern telecommunication networks face an increasing demand for services. Among these, an increasing number are services that can adapt to available bandwidth, and are therefore referred to as elastic traffic. Nominal network design for elastic traffic becomes increasingly significant. Typical resource allocation methods are concerned with the allocation of limited resources among competing activities so as to achieve the best overall performance of the system. In the network dimensioning problem for elastic traffic, one needs to allocate bandwidth to maximize service flows and simultaneously to reach a fair treatment of all the elastic services. Thus, both the overall efficiency (throughput) and the fairness (equity) among various services are important. In such applications, the so-called Max-Min Fairness (MMF) solution concept is widely used to formulate the resource allocation scheme. This approach guarantees fairness but may lead to significant losses in the overall throughput of the network. In this paper we show how the concepts of multiple criteria equitable optimization can be effectively used to generate various fair resource allocation schemes. We introduce a multiple criteria model ecluivalent to equitable optimization and we develop a corresponding reference point procedure to generate fair efficient bandwidth allocations. The procedure is tested on a sample network dimensioning problem and its abilities to model various preferences are demonstrated.

6

Multiple criteria optimization and decisions under risk

Ogryczak W.

Control and Cybernetics

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2002

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Vol. 31, no 4

975-1003

EN

The mathematical background of multiple criteria optimization (MCO) is closely related to the theory of decisions under uncertainty. Most of the classical solution concepts commonly used in the MCO methodology have their origins in some approaches to handling uncertainty in decision analysis. Nevertheless, the MCO as a separate discipline has developed several advanced tools of interactive analysis leading to effective decision support techniques with successful applications. Progress made in the MCO tools raises a question of possible feedback to the decision making under risk. The paper shows how decisions under risk, and specifically the risk aversion preferences, can be modeled within the MCO methodology. This provides a methodological basis allowing for taking advantage of the interactive multiple criteria techniques for decision support under risk.

PL

Podstawy matematyczne optymalizacji wielokryterialnej są blisko związane z teorią podejmowania decyzji w warunkach ryzyka. Większość klasycznych koncepcji rozwiązań zazwyczaj wykorzystywanych w metodach optymalizacji wielokryterialnej pochodzi z pewnych podejść uwzględniania niepewności w analizie decyzji. Jednakże, należy podkreślić, że optymalizacja wielokryterialna, jako niezależna dyscyplina, rozwinęła szereg zaawansowanych narzędzi analizy interaktywnej, prowadzących do efektywnych technik wspomagania decyzji, znajdujących rzeczywiste zastosowania. Postęp, jaki się dokonał w zakresie narzędzi wielokryterialnego podejmowania decyzji, stawia pytanie o ewentualne sprzężenie zwrotne w kierunku podejmowania decyzji w warunkach ryzyka. W artykule pokazano, jak decyzje z ryzykiem, a szczególnie preferencje co do unikania ryzyka, mogą być modelowane przy użyciu metodyki optymalizacji wielokryterialnej. W ten sposób stworzono podstawę metodyczną pozwalającą korzystać z interaktywnych technik wielokryterialnych we wspomaganiu decyzji z ryzykiem.