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1

Optimization Method Based on Minimization M-Order Central Moments Used In Surveying Engineering Problems

Cellmer Sławomir, Bobojć Andrzej

Technical Sciences / University of Warmia and Mazury in Olsztyn

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2021

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nr 24(1)

39--49

EN

A new optimization method presented in this work – the Least m-Order Central Moments method, is a generalization of the Least Squares method. It allows fitting a geometric object into a set of points in such a way that the maximum shift between the object and the points after fitting is smaller than in the Least Squares method. This property can be very useful in some engineering tasks, e.g. in the realignment of a railway track or gantry rails. The theoretical properties of the proposed optimization method are analyzed. The computational problems are discussed. The appropriate computational techniques are proposed to overcome these problems. The detailed computational algorithm and formulas of iterative processes have been derived. The numerical tests are presented, in order to illustrate the operation of proposed techniques. The results have been analyzed, and the conclusions were then formulated.

2

Distance between two Keplerian orbits

Mohamed Ayman Homda, Dwidar Hany Ramdan, Adham Inal, Bakry Abd-Elazaz, El-Raffie Ahmed

Artificial Satellites : Journal of Planetary Geodesy

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2021

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Vol. 56, No. 3

57--77

EN

In this paper, constrained minimization for the point of closest approach of two conic sections is developed. For this development, we considered the nine cases of possible conics, namely, (elliptic-elliptic), (elliptic-parabolic), (elliptic–hyperbolic), (paraboli-elliptic), (paraboli-parabolic), (parabolic–hyperbolic), (hyperbolic-elliptic), (hyperbolic-parabolic), and (hyperbolic–hyperbolic). The developments are considered from two points of view, namely, analytical and computational. For the analytical developments, the literal expression of the minimum distance equation (S) and the constraint equation (G), including the first and second derivatives for each case, are established. For the computational developments, we construct an efficient algorithm for calculating the minimum distance by using the Lagrange multiplier method under the constraint on time. Finally, we compute the closest distance S between two conics for some orbits. The accuracy of the solutions was checked under the conditions that L|solution ≤ε1G||solution ≤ε2, where ε1,2 < 10 -10. For the cases of (paraboli-parabolic), (paraboli-hyperbolic), and (hyperbolic-hyperbolic), we studied thousands of comets, but the condition of the closest approach was not met.

3

An inverse procedure for characterization of material parameters of passive skeletal muscle using FEM and experimental data

Liu Shuailong, Sang Jianbing, Zhang Yi, Zhao Luming, Liu Guirong

Journal of Theoretical and Applied Mechanics

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2020

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Vol. 58 nr 1

247--259

EN

This work develops an inverse procedure which combines an improved niche genetic algorithm, finite element models and experimental data to identify material parameters of biological tissues behaving like hyperelastic materials. A novel objective function is proposed with two coefficients, which controls the contributions in a well-balanced fashion, respectively, for the small deformation stage and the large deformation stage. This allows us to obtain a global minimizer (of material constants) for the error between FEM solutions and experimental data. Moreover, simple uniaxial compression tests at two different angles (0◦ and 90◦) with respect to the muscle fiber orientation are performed on fresh muscle tissues. This enables us to obtain anisotropic properties of the muscle tissue from the present inverse procedure. The result shows that the proposed inverse procedure is stable and reliable to determine material constants in hyperelastic models for soft biological tissues like skeletal muscles considering anisotropy.

4

Towards a distributed solution to multi-robot task allocation problem with energetic and spatiotemporal constraints

Zitouni Farouq, Harous Saad, Maamri Ramdane

Computer Science

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2020

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T. 21 (1)

3--24

EN

This paper tackles the Multi-Robot Task Allocation problem. It consists of two distinct sets: a set of tasks (requiring resources), and a set of robots (offering resources). Then, the tasks are allocated to robots while optimizing a certain objective function subject to some constraints; e.g., allocating the maximum number of tasks, minimizing the distances traveled by the robots, etc. Previous works mainly optimized the temporal and spatial constraints, but no work focused on energetic constraints. Our main contribution is the introduction of energetic constraints on multi-robot task allocation problems. In addition, we propose an allocation method based on parallel distributed guided genetic algorithms and compare it to two state-of-the-art algorithms. The performed simulations and obtained results show the effectiveness and scalability of our solution, even in the case of a large number of robots and tasks. We believe that our contribution is applicable in many contemporary areas of research such as smart cities and related topics.

5

Zastosowanie symulacji komputerowych w badaniach algorytmów rekonstrukcji rezystancji siatek rezystorów

Zegarmistrz Piotr, Malcharek Anna

Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej

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2019

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Nr 68

73--76

PL

Przedmiotem niniejszej pracy jest analiza możliwości zastosowania logiki rozmytej i systemów ekspertowych w procesie doboru najlepszej metody rozwiązania problemu rekonstrukcji rezystancji kwadratowych siatek rezystorów. Bazując na badaniach skuteczności algorytmów rekonstrukcji oraz oprogramowaniu Fuzzy Logic Toolbox opracowano system pozwalający na wskazanie najlepszej metody odtwarzania parametrów siatki w zależności od ustalonych kryteriów, takich jak np. najkrótszy czas obliczeń czy najwyższa dokładność.

EN

This paper describes simulation tests of the effectiveness of numerical algorithms for reconstruction of resistances in square resistive grids. Both metaheuristic and optimization algorithms based on defined objective function, as well as analytical algorithm is analyzed. Authors propose an application allowing to choose a best method for a given conditions, based on fuzzy logic and expert systems.

6

Optimal configuration of standalone wind-solar-storage complementary generation system based on the GA-PSO algorithm

Sun Qian, Ma Jianwei, She Yanjie, Zhang Jingchao, Gu Bo, Zhang Zichao

Journal of Power Technologies

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2019

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Vol. 99, nr 4

231--236

EN

The capacity configuration of the standalone wind–solar–storage complementary power generation system (SWS system) is affected by environmental, climate condition, load and other stochastic factors. This makes the capacity configuration of the SWS system problematic when the capacity configuration method of traditional power generation is used. An optimal configuration method of the SWS system based on the hybrid genetic algorithm and particle swarm optimization (GA-PSO) algorithm is proposed in this study to improve the stability and economy of the SWS system. The constituent elements of investment, maintenance cost and various reliability constraints of the SWS system were also discussed. The optimal configuration of the SWS system based on GA-PSO was explored to achieve the optimization objective, which was to minimize investment and maintenance costs of the SWS system while maintaining power supply reliability. The investment and maintenance costs of the SWS system under different configuration methods were calculated and analyzed on the bases of the monthly mean wind speed, solar radiation and load data of Xiaoertai Village in Zhangbei County of Hebei Province in the last 10 years. Results show that the optimal configuration method based on the GA-PSO algorithm could effectively improve the economy of the system and meet the requirements of system stability. The proposed method shows great potential for guiding the optimal configuration of the SWS system in remote areas.

7

Determination of Approaches for Project Costs Minimization with Use of Dual Problems

Chernov S., Titov S., Chernova L., Kunanets N., Chernova L.

ECONTECHMOD : An International Quarterly Journal on Economics of Technology and Modelling Processes

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2019

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Vol. 8, No 2

61--68

EN

For determining ways of company development, ensuring the growth of profit in manufacture and sales of certain products, it has been proposed to use an algorithm of constructing a problem being inverse to primal-dual one, for minimization of the project costs. The primal and the inverse problems contribute to improving the efficiency of calculation when determining approaches for minimization of costs. This pair of problems is mutually conjugate. The proposed rigorous approach to obtaining the algorithm of constructing a dual problem is based on the following statement: a problem being inverse to a dual one is a primal (original) problem. The authors have proposed and rigorously proven the algorithm of a general approach to the construction of conjugate problem pairs. Formalization of the algorithm developed allows obtaining easily correct pairs of known dual problems. This permitted proposing and proving the truth of the algorithm of constructing a dual problem for the arbitrary form of a primal problem representation.

8

Optymalizacja transportu publicznego

Dębowska-Mróz Marzenna, Rogowski Andrzej

Autobusy : technika, eksploatacja, systemy transportowe

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2019

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R. 20, nr 12

37--41

PL

W artykule omówiony został problem optymalizacji transportu publicznego. Zdefiniowano typowe zagadnienia związane z optymalizacją transportu publicznego, w szczególności: etapy planowania sieci transportu publicznego, sposób opisu sieci transportowej, konstruowanie funkcji celu, synchronizacji rozkładów jazdy, klasyfikacji węzłów sieci, metody rozwiązania zadania.

EN

The article discusses the problem of optimization of public transport. Defined typical issues related to the optimization of public transport, in particular: stages of public transport network planning, way of description of transport network, construction of the objective function, synchronization of timetables, classification of network nodes, methods of solving the task.

9

Quality Management in the Process of Selection of Material for Dump Truck Elements

Ulewicz R., Nový F.

Multidisciplinary Aspects of Production Engineering

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2018

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Vol. 1, Iss. 1

665--671

EN

The article presents the problem of quality management in the process of material selection for structural elements of a car dump truck. The study took into account the classical management pyramid and there was used the optimization method (generalized objective function). The center that manages the process of production / assembly of the dump truck should be the level of organization that has the highest degree of processing of required information and making strategic decisions in this respect. The design process of structural elements is carried out primarily in terms of the ability to provide adequate physical and mechanical properties in the process. There is a very strong tendency to reduce the own weight of the semi-trailers by increasing the weight of the load. This is an important criterion from the point of view of the economics of operation of technical facilities of this type. The article presents the results of the application of a generalized objective function in the field of material selection for construction elements of a dump truck. The analysis includes structural elements made of S355 steel and Hardox 400 and 450 fine-grain steel.

10

The importance of calibration parameters on the accuracy of the floods description in the Snyder’s model

Wałęga A.

Journal of Water and Land Development

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2016

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no. 28

19--25

EN

Comparison of quality of Snyder’s model for determination flood waves was examination in this work. Model parameters were calibrated based on objective functions: percentage error in peak flow (PEPF), percentage error in volume (PEV), peak-weighted root mean square error (PWRMSE), sum of absolute residuals (SAR) and sum of squared residuals (SSR). Quality of model was calculating by Nash-Sutcliffe efficiency coefficient E. Additionally sensitivity of a model was characterized by its flexibility. The analyses were performed in the watershed of Grabinka. It has been found that the use PWRMSE as the objective function allows to obtain the best quality results of simulation. Furthermore, Snyder’s model is flexible to the change of Cp coefficient.

PL

W pracy porównano efektywność modelu Snydera w opisie wezbrań opadowych, którego parametry szacowano za pomocą różnych funkcji celu: procentowego błędu przepływu w kulminacji – PEPF, procentowego błędu objętości fali – PEV, ważonych średnich kwadratów błędu – PWRMSE, absolutnych sum reszt – SER i sum kwadratów reszt – SSR. Jakość modelu oceniono za pomocą współczynnika efektywności Nash– Sutcliffe’a. Dodatkowo zbadano wpływ zmiany wartości parametrów na wielkości przepływu uzyskane z modelu za pomocą współczynnika elastyczności. Analizy prowadzono w zlewni rzeki Grabinki. Stwierdzono, że zastosowanie PWRMSE jako funkcji celu umożliwia na uzyskanie najlepszej zgodności wyników z modelu z przepływami obserwowanymi. Ponadto model Snydera jest wrażliwy na zmiany parametru Cp, który może być utożsamiany z retencyjnością zlewni.

11

Evaluation of biogas production and usage potential

Kalinichenko A., Havrysh V., Perebyynis V.

Ecological Chemistry and Engineering. S

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2016

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Vol. 23, nr 3

387--400

EN

The aim of the research is the development of theoretical and methodical bases for determining the feasibility of plant raw materials growing for its further bioconversion into energy resources and technological materials to maximize profit from business activities. Monograph, statistics, modelling and abstract logical methods have been used during the research. Directions of biogas usage have been examined. Biogas yields from different crops have been analyzed. It has been determined that high methane yields can be provided from root crops, grain crops, and several green forage plants. So, forage beet and maize can provide more than 5,500 m3 of biogas per hectare. Attention is paid to the use of by-products of biogas plants, especially carbon dioxide. Carbon dioxide is an important commodity and can increase profitability of biogas plant operating. It can be used for different purposes (food industry, chemical industry, medicine, fumigation, etc). The most important parameters of the biogas upgrading technologies have been analyzed. If output of an upgrade module is more than 500 nm3/h, investment costs of different available technologies are almost equal. According to experts, it is economically feasible to use anaerobic digestion biogas systems to upgrade biomethane provided their performance is equivalent to 3,000 litres of diesel fuel per day. The economic and mathematical models have been suggested to determine the feasibility of growing plant materials to maximize the gross profit. The target function is the maximum gross income from biogas utilization. It has the following limitations: annual production of biogas, consumption of electricity, heat and motor fuels. The mathematical model takes into account both meeting own requirement and selling surplus energy resources and co-products including carbon dioxide. In case of diesel fuel substitution, an ignition dose of diesel fuels has been considered. The algorithm for making a decision on construction of a biogas plant has been offered.

12

Influence of piston compressor inner failure on mechanical system objective function

Urbanský M., Homišin J., Kaśśay P., Moravič M.

Diagnostyka

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2016

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Vol. 17, No. 3

47--52

EN

At our department we deal with continuous tuning of torsional oscillating mechanical systems during their operation using pneumatic tuners, mainly in terms of torsional vibrations magnitude, whereby we use the methods and means of technical diagnostics. One of the manners of continuous tuning realization is the application of extremal control – experimental optimization, which main advantage is that we don’t need to know the mathematical model of mechanical system. We must know only that the objective function of mechanical system has an extreme. For that reason, it is very important to know this form of objective function not only at failure-free operation but at failure occurrence as well. The objective of this paper is therefore the investigation of the influence of piston compressor inner failure, namely cylinder(s) fall-out on mechanical system objective function form.

13

Wybrane problemy optymalizacyjne strategicznego planowania w komunikacji miejskiej

Kisielewski P.

Logistyka

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2014

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nr 6

14337--14346, CD 6

PL

W pracy omówiono proces planowania strategicznego w komunikacji miejskiej. Przedstawiono w kolejności i pokrótce scharakteryzowano poszczególne etapy procesu tj. projektowanie globalnej sieci, planowanie linii komunikacyjnych i rozkładów jazdy. Przytoczono zasadnicze pozycje światowej literatury odnoszące się do procesu. Niezbędne dane do procesu planowania stanowią wyniki pomiarów potoków pasażerskich i ankietyzacji, przedstawiane w postaci więźby ruchu i macierzy migracji. W skrócie przedstawiono również modelowanie miejskiej sieci komunikacyjnej z wykorzystaniem teorii grafów. W pracy zaprezentowano modele matematyczne optymalizacji, funkcje celu, zmienne decyzyjne i ograniczenia, zastosowane w algorytmach komputerowego wspomagania procesu planowania. Funkcja celu na każdym etapie uwzględnia kompromis pomiędzy komfortem pasażerów i kosztem organizacji transportu. Przedstawiono przykłady i wnioski pod kątem wykorzystania w praktycznych implementacjach.

EN

In the paper the process of strategic planning in city transit has been described. Specific stages of the process, that is global network design, line planning and timetabling have been presented in turn and characterized. The worldwide basic references concerning the process have been denoted. Necessary data to planning process are taken from passenger flow measurements and questionnaires, presented in a form of passenger journey chart and migration matrix. Modeling of city transit network with the use of graph theory has been also briefly presented. Mathematical models of optimization, objective functions, decision variables and constrains applied in the algorithms of computer aided planning process have been described in the paper. The objective function at each stage of the process takes into account the compromise between the passenger comfort and the operational cost of transport. The examples and conclusions regarding practical implementations have been presented.

14

A comparison of objective functions of optimization-based smoothing algorithm for tetrahedral mesh improvement

Dai C., Liu H.-L., Dong L.

Journal of Theoretical and Applied Mechanics

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2014

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Vol. 52 nr 1

151--163

EN

The objective function based on mesh quality metric has a major impact on smoothing unstructured tetrahedral meshes. The ability of seven mesh quality metrics to distinguish four kinds of poor-quality elements and their effects on the change of element shape are analyzed in detail. Then, four better mesh quality metrics are chosen to construct objective functions. In addition, the rational determination of searching direction and the optimal step size in the optimization algorithm of solving the objective function are proposed. Finally, comparisons with the other three objective functions are made according to different number of elements, iteration limit, and the desired accuracy in the improved mesh. It is found that with the increase of the number of elements, the time consumed during optimization increases, but the changes of the worst quality element are different. The number of iterations has little effect on the mesh quality and the time cost. The increasing of the desired degree of accuracy will improve the mesh quality and cost more time. Furthermore, the approach using objective function is compared with Freitag’s common approach. It is clearly shown that it performs better than the existing approach.

15

Determination of the main characteristics of the small waterplane area twin hull ships at the initial stage of design

Bondarenko O. V., Boiko A. P., Seropyan I. R.

Polish Maritime Research

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2013

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nr 1

11--22

EN

The basic selecting peculiarities of the optimal project characteristics of the small waterplane area twin hull ships compared to conventional ships are considered. The description of the mathematical model and the ship operating model is given. The choice of the optimization method is justified.

16

Optimization criteria in end-of-life products reverse logistics network organization

Merkisz-Guranowska A., Maciejewski M.

Logistics and Transport

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2013

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Vol. 17, No. 1

25--32

EN

The paper discusses the problem of selection of objective function in modeling of the reverse logistics network entity location. A growing ecological awareness of societies as well as implementing concepts of manufacturer responsibility for their products result in a creation of systems of collecting and treatment of end-of-life products. Rather than being a random process a reverse logistics network should be designed as an effect of informed decisions taking into account all aspects and points of view of the stakeholders. A key issue in network design related to the use of decision support tools based on mathematical optimization is the appropriate selection of the objective function for evaluation of the potential solutions.

17

Optimization of linear parametric circuits in the frequency domain

Shapovalov Yu., Mandziy B., Bachyk D.

ECONTECHMOD : An International Quarterly Journal on Economics of Technology and Modelling Processes

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2013

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Vol. 2, No 4

73-77

EN

The possibility of application of the frequency symbolic method of analysis of linear parametric circuits to the decision of optimization tasks is considered. There are examples of optimization of single- and doublecircuit parametric amplifier using the objective function based on the calculation of parametric transfer function of a circuit with a symbolic representation of the parameters of the parametric capacity. By the frequency symbolic method the parametric transfer functions are approximated by trigonometric polynomials of Fourier.

18

On the choice of calibration periods and objective functions: a practical guide to model parameter identification

Romanowicz R., Osuch M., Grabowiecka M.

Acta Geophysica

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2013

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Vol. 61, no. 6

1477--1503

EN

Despite the development of new measuring techniques, monitoring systems and advances in computer technology, rainfall-flow modelling is still a challenge. The reasons are multiple and fairly well known. They include the distributed, heterogeneous nature of the environmental variables affecting flow from the catchment. These are precipitation, evapotranspiration and in some seasons and catchments in Poland, snow melt also. This paper presents a review of work done on the calibration and validation of rainfall-runoff modelling, with a focus on the conceptual HBV model. We give a synthesis of the problems and propose a practical guide to the calibration and validation of rainfall-runoff models.

19

Kryteria optymalizacji w lokalizacji podmiotów sieci recyklingu pojazdów

Merkisz-Guranowska A.

Logistyka

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2012

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nr 4

PL

W artykule poruszono zagadnienia wyboru funkcji kryterium w modelowaniu lokalizacji przedsiębiorstw sieci recyklingu. Współcześnie coraz częściej wykorzystuje się do projektowania sieci recyklingu jedno i wielokryterialne metody wspomagania decyzji. Jednokryterialne zadania optymalizacyjne najczęściej wykorzystują funkcję minimalizacji kosztów funkcjonowania sieci. W pewnych przypadkach trudno jest posługiwać się jedną funkcją celu z uwagi na wiele zaangażowanych podmiotów, co przekłada się na różne punkty widzenia poszczególnych uczestników procesu recyklingu, z których każdy stara się ekstremalizować swoją indywidualną korzyść. W takich przypadkach niezbędnym staje się stosowanie wielokryterialnego podejścia do wspomagania decyzji, które zakłada minimalizację/maksymalizację funkcji celu złożonej z wielu kryteriów cząstkowych.

EN

The paper discusses the issue of choosing the criteria function in modeling of the vehicle recycling network entities location. Today, mono and multi criteria decision support methods are used in recycling network design. Mono criteria optimization tasks usually use the objective function that minimizes the cost of network operation. Sometimes, it is difficult to use a single objective function because of the many stakeholders involved that have different points of views and expectations towards the recycling network and each of them tries to extremize their individual benefits. In such cases, it is necessary to use multi criteria approach to decision making process which involves minimizing/maximizing the objective function composed of several partial criteria.

20

Identyfikacja obiektów dyskretnych w kontekście propagacji zaburzeń

Szymańda J.

Logistyka

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2012

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nr 3

PL

W referacie przedstawiono propozycję identyfikacji obiektów dyskretnych wykorzystującej koncepcje filtrów estymacyjnych. Podstawę proponowanej metody identyfikacji stanowią zmodyfikowane algorytmy estymacji. Postuluje się dołączenie filtrów estymacyjnych do kategorii pojęć związanych z filtrami adaptacyjnymi, sieciami neuronowymi i algorytmami genetycznymi. Kontekstem aplikacyjnym artykułu są zagadnienia logistyki wybranych elementów wytwarzania i dystrybucji energii elektrycznej, w szczególności kontroli jakości energii dostarczanej do odbiorców końcowych. Prezentowane wyniki obejmują wybrane elementy projektu w ramach prac podstawowych w zakresie archiwizacji i szybkiej identyfikacji sygnałów elektrycznych. Modelowanie systemu propagacji zaburzeń zrealizowano przy wykorzystaniu pakietu PSCAD X4.

EN

In this paper the proposal of the identification of discrete objects using concepts of estimation filters is presented. Estimation methods and mathematical programming have been the subject of the first stage of the research project:“Novel signal processing methods and global power quality indices for assessment of power systems with distributed generation”. The results are presented in the context of archiving and quick identification of electrical signals. Modeling system of propagation disturbance using PSCAD X4 package was carried out.