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1

Modelling of expansion changes of Vilnius city area and impacts on landscape patterns using an artificial neural network

Mirsanjari Mir Mehrdad, Suziedelyte-Visockiene Jurate, Mohammadyari Fatemeh, Zarandian Ardavan

Ecological Chemistry and Engineering. S

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2021

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Vol. 28, nr 3

429--447

EN

The present study aimed to analyse changes in the land cover of Vilnius city and its surrounding areas and propose a scenario for their future changes using an Artificial Neural Network. The land cover dynamics modelling was based on a multilayer perceptron neural network. Landscape metrics at a class and landscape level were evaluated to determine the amount of changes in the land uses. As the results showed, the Built-up area class increased, while the forest (Semi forest and Dense forest) classes decreased during the period from 1999 to 2019. The predicted scenario showed a considerable increase of about 60 % in the Built-up area until 2039. The vegetation plant areas consist about 47 % of all the area in 2019, but it will be 36 % in 2039, if this trend (urban expansion) continues in the further. The findings further indicated the major urban expansion in the vegetation areas. However, Built-up area would expand over Semi forest land and Dense forest land, with a large part of them changed into built- up areas.

2

Facies anatomy of a progradational submarine channelized lobe complex: semi-quantitative analysis of the Ropianka Formation (Campanian-Paleocene) in Hucisko Jawornickie section, Skole Nappe, Polish Carpathians

Łapcik Piotr

Acta Geologica Polonica

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2019

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Vol. 69, no. 1

111--141

EN

This study is a detailed lithofacies analysis of the Wiar and Leszczyny members of the deep-marine Ropianka Formation (Campanian–Paleocene) exposed in the Hucisko Jawornickie section of the Skole Nappe, Polish Carpathian Flysch. The sedimentary succession (>400 m thick) represents a channelized lobe complex that prograded at the base of submarine slope. Seven sedimentary facies are recognized as a record of the principal modes of sediment deposition. Based on their stratigraphic grouping and grain-size trends, six facies associations are distinguished as representing specific sub-environments of the depositional system: distributary channels, channel-mouth lobes, channel levees, crevasses and interlobe basin plain with crevasse splays. The individual facies associations are characterized statistically and their internal facies organization is analysed by the method of embedded Markov chains to reveal the time pattern of depositional processes. The environmental changes indicated by the vertical succession of facies associations are attributed to the autogenic processes of the distributary channel shifting within an aggrading lobe area and the lateral switching of depositional lobes. Eustatic influences are likely, but difficult to ascertain with poor biostratigraphic data. The bulk basinward advance of the base-of-slope system was probably due to a pulse of the tectonic narrowing of the synclinal Skole Basin.

3

Comparison of Reliability in Modular Multilevel Inverters

Rashidi-Rad N. N., Rahmati A., Abrishamifar A.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 1b

268-272

EN

This paper studies the reliability of modular inverters with Half-Bridge and Full-Bridge cells. To calculate their reliability Markov Chain which models a sequence of random variables has been used. Therefore two main methods of reliability enhancement will be compared. Selecting one of these methods to have a fault tolerant system is based on the number of phase voltage levels. Finally, it can be concluded that, modular inverters with HB cells will have a better reliability compared to the inverters with FB cells.

PL

W pracy analizowana jest niezawodność modularnego przekształtnika z celkami typu półmostek i cały mostek. Do analizy użyto łańcucha Markova. Porównano też dwie metody poprawy niezawodności - jako kryterium przyjmując tolerancję błędu. Stwierdzono przewagę układów wykorzystujących półmostek.

4

The island model as a Markov dynamic system

Schaefer R., Byrski A., Smołka M.

International Journal of Applied Mathematics and Computer Science

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2012

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Vol. 22, no. 4

971-984

EN

Parallel multi-deme genetic algorithms are especially advantageous because they allow reducing the time of computations and can perform a much broader search than single-population ones. However, their formal analysis does not seem to have been studied exhaustively enough. In this paper we propose a mathematical framework describing a wide class of island-like strategies as a stationary Markov chain. Our approach uses extensively the modeling principles introduced by Vose, Rudolph and their collaborators. An original and crucial feature of the framework we propose is the mechanism of inter-deme agent operation synchronization. It is important from both a practical and a theoretical point of view. We show that under a mild assumption the resulting Markov chain is ergodic and the sequence of the related sampling measures converges to some invariant measure. The asymptotic guarantee of success is also obtained as a simple issue of ergodicity. Moreover, if the cardinality of each island population grows to infinity, then the sequence of the limit invariant measures contains a weakly convergent subsequence. The formal description of the island model obtained for the case of solving a single-objective problem can also be extended to the multi-objective case.

5

Multiple hypotheses optimal testing for Markov chains and identification subject to the reliability criterion

Navaei L.

Journal of Mathematics and Applications

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2010

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Vol. 33

79-90

EN

The problem of many (L > 2)hypotheses testing on distributions of a finite state Markov chain is studied. We apply large deviation techniques (LDT). It is demonstrated that this method of investigation in solving the problem of logarithmically asymptotically optimal (LAO) hypotheses testing is easier, compared with the procedure introduced by Haroutunian. The matrix of exponents [formula/wzór], of error probabilities of the LAO test [formula/wzór] is the probability to accept the hypothesis l, when the hypothesis m is true, is determined. Moreover, the identification of distributions for one object and two independent objects via simple homogeneous stationary Markov chains with finite number of states is discussed in the present paper.

6

Equations for the Response Probability Density of Dynamic Systems under Multi-Component Non-Poisson Impulse Process Excitations

Iwankiewicz R.

Machine Dynamics Problems

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2008

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Vol. 32, No. 4

24-36

EN

The excitation considered in the present paper consists of n statistically independent random trains of impulses, each of whom is driven by a non-Poisson, renewal process with inter-arrival times being the sum of two independent negative-exponential distributed random variables with parameters vv, Vs, µs (S = 1, 2, ..., n). Each of the original impulse processes is recast into a Poisson driven impulse process with the aid of an auxiliary, purely jump stochastic variable. Each auxiliary variable is governed by the stochastic differential equation driven by two independent Poisson processes, with parameters Vs, µs, thus it is tantamount to two Markov states. The Markov chain for the whole problem is constructed by considering the coincidences of the states of the individual jump processes. The necessary so-called jump probability intensity functions are determined for all state variables and all possible jumps. The equations governing the joint probability density-distribution function of the response and of the Markov states of the auxiliary variables are derived from the general integro-differential forward Chapman-Kolmogorov equation. The resulting equations form a set of integro-partial differential equations.

7

Wielowymiarowe modele sterowania zapasami i ich zastosowanie

Wojna A., Kłodzińska A.

Badania Operacyjne i Decyzje

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2005

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nr 2

83-90

PL

W artykule przeprowadzono matematyczną formalizację wielowymiarowych modeli sterowania zapasami z wykorzystaniem procesów sum zmiennych losowych określonych na łańcuchu Markowa. Na podstawie tej formalizacji określono funkcję ryzyka funkcjonowania wielowymiarowych modeli sterowania zapasami. Rozpatrzono również zagadnienie analizy niezawodności funkcjonowania oraz ustalenia optymalnej struktury specjalnego systemu obsługi Markowa za pomocą określenia jego funkcji ryzyka.

EN

The multidimensional stock control that functions in a random Markov environment is considered. The mathematical formalization of this model was considered with the use of sums of the random variables de-fmed on the Markov chains. The authors introduce a definition of risk function of the type of downside risk measures and find the explicit formulas for its determinations. The example of the application of these formulas is provided: the tasks of the reliability and optimal configuration for the queueing problem are regarded. The formulas defining the function by the system parameters were obtained

8

Problemy obliczeniowe zdyskontowanych stacjonarnych łańcuchów Markowa z zastosowaniem arkusza kalkulacyjnego MS Excel

Zdonek I.

Zeszyty Naukowe. Organizacja i Zarządzanie / Politechnika Śląska

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2002

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z. 9

257-265

PL

W pracy w oparciu o analityczną metodę wyznaczania macierzy ergodycznej i różnicowych przedstawiono obliczeniowe problemy, których rozwiązanie jest konieczne dla potrzeb utworzenia programu w arkuszu kalkulacyjnym, pozwalającego na numeryczne obliczanie elementów tych macierzy na podstawie danej stochastycznej macierzy P.

EN

In the work we present the calculated problems of determination the ergodic and difference matrices, which solutions are required to create a program permitting calculate numerically these elements on the grounf of stochastic matrix P.

9

Przebieg uszkodzeń obiektu technicznego ulegającego procesom starzeniowym.

Boda A.

Zagadnienia Eksploatacji Maszyn

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1999

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Vol. 34, nr 2

235-247

PL

Starzenie fizyczne maszyn zachodzi najczęściej w wyniku występujących procesów destrukcyjnych związanych z tarciem. Prowadzi to w nich - w miarę upływu czasu ich eksploatacji - do coraz częstszego pojawiania się uszkodzeń i obniżenia niezawodności. W pracy przedstawiono modele opisujące proces uszkodzeń wybranych obiektów technicznych, należące do modeli sekwencyjno-prognostycznych o charakterze adaptacyjnym. Rozważa się obiekt naprawialny o dużej trwałości, posiadający pewną klasę elementów wymiennych, które stanowią jeden względnie grupę technicznie jednorodnych elementów o stosunkowo małej trwałości, spełniające w obiekcie istotną funkcję. Przebieg uszkodzeń tych elementów w czasie opisuje się przy pomocy jednorodnych łańcuchów Markova, w których elementy macierzy prawdopodobieństw przejść wyznacza się z danych stale aktualizowanego rozkładu empirycznego trwałości elementu rozważanej klasy lub też korzysta się ze wzoru Bayesa. Przedstawionym innym podejściem jest wyznaczenie funkcji ubywania w czasie niezawodności obiektu w oparciu o dane uzyskane z badań kontrolnych prowadzonych po upływie każdego ustalonego okresu pracy obiektu.

EN

The physical ageing of machines is the process resulting of destruction processes connected with friction. This leads to more and more frequent failures and lowering of their reliability with time of their operational service. In this work are presented models describing the process of defects of some technological objects which belong to sequence-prognostic models of adaptative features.