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1

Method of agents’ state estimation in multiresolution multiagent simulation

Pierzchała D., Czuba P.

Computer Science and Mathematical Modelling

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2018

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No. 8

29--39

EN

The paper proposes the multiagent techniques for approximation of agent’s state in the multiresolution multiagent simulation. The key methods we have used for state aggregation and disaggregation are: consensus algorithm and formation control. The idea of the coordination of multiple agents has emerged from both observation and simulation of a collective behavior of biological entities. The consensus algorithms are commonly used for the cooperative control problems in the multiagent systems, whilst the formation control is the most popular and fundamental motion coordination problem in the multiagent systems, where agents converge to predefined geometric shapes. The presented approach shows that multiagent methods seem to be very promising in multiresolution simulation. Consensus and formation control algorithms remove necessity to specify the much more complex algorithms for the aggregation and disaggregation needs.

PL

W artykule zaproponowano wieloagentowe podejście do wyznaczania stanu agenta w symulacji wielorozdzielczej (o zmiennej rozdzielczości) i wieloagentowej. Dwie kluczowe metody zastosowane do realizacji procesu agregacji i deagregacji stanów to: algorytm konsensusu i kontroli formacji. Idea koordynacji działań wielu agentów wyłoniła się z obserwacji oraz symulacji zbiorowych zachowań żywych istot. Algorytmy konsensusu są powszechnie stosowane w przypadku problemów sterowania kooperacyjnego w systemach wieloagentowych (konsensus oznacza osiągnięcie zgody na temat szczególnej wartości, która jest zależna od stanu wszystkich agentów w sieci). Natomiast kontrola formacji jest najpopularniejszym algorytmem w problemie koordynacji ruchu w systemach wielorobotowych, gdzie musi być spełniony warunek utrzymania predefiniowanego kształtu geometryczne formacji. Przedstawione w artykule podejście pokazuje, że metody wielodyscyplinarne wydają się bardzo obiecujące w symulacji wielorozdzielczej. Algorytmy konsensu i kontroli formacji eliminują konieczność definiowania znacznie bardziej złożonych algorytmów na potrzeby agregacji i deagregacji.

2

Analiza środków ochrony środowiska w inwestycjach drogowych na obszarach Natura 2000 w Polsce

Kozieł M., Bednarczyk P., Czuba P., Gawrysiak L.

Drogownictwo

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2015

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nr 12

406--414

PL

Polska jest obecnie największym placem budowy nowoczesnej infrastruktury drogowej w Europie. Skala realizowanych i planowanych w Polsce inwestycji drogowych sprawia, że uniknięcie kolizji z obszarami Natura 2000 lub innymi obiektami przyrodniczo cennymi (w tym korytarzami migracyjnymi) nie zawsze jest możliwe. Wytypowanie „problemowych” obszarów pozwala zaoszczędzić czas i koszty związane z procesem inwestycyjnym oraz ułatwia podjęcie właściwej decyzji co do przebiegu najlepszego wariantu drogi, jak również uniknięcie błędów popełnianych na etapie projektowania drogi i infrastruktury towarzyszącej łagodzącej niekorzystny wpływ inwestycji. Autorzy publikacji, korzystając z narzędzi GIS oraz z danych z monitoringu zwierząt wykonali analizy środków i kosztów związanych z ochroną środowiska inwestycji drogowej na obszarze Natura 2000 w Polsce.

EN

Poland is currently the biggest construction site of modern road infrastructure in Europe. The scale of ongoing and planned road projects in Poland makes avoiding collisions with the Nature 2000 areas or other valuable natural objects (including migration corridors) is not always possible. Predicting “problematic” areas can save time and costs associated with the investment process and makes it easier to make the right decision about the best course of option routes, as well as to avoid the mistakes made in the design of the road and associated infrastructure mitigating the adverse impact of the investment. The authors, using GIS tools and data from monitoring the animals, made the analyzes of the environmental costs of investment in the area of Nature 2000 in Poland.

3

Pierwsza generacja swiatłowodowego systemu dystrybucji sygnału odniesienia dla akceleratora TESLA

Czuba P., Dobrowolski J., Eints F., Felber M.

Elektronika : konstrukcje, technologie, zastosowania

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2005

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Vol. 46, nr 7

69-70

PL

Przedstawiono projekt oraz wyniki pomiarów parametrów prototypu systemu optycznego przygotowanego do precyzyjnej synchronizacji urządzeń akceleratora TESLA. Dla systemu dystrybucji sygnału o długości 20 km i sygnatu o częstotliwości 1,3 GHz uzyskano długoterminową (12 h) stałość fazy około 3° (6 ps) oraz stałość krótkoterminową (1 min) rzędu 0,35° (0,7 ps).

EN

This paper describes design and performance measurements of the prototype of the optical system that will be used for precise synchronization of the TESLA accelerator subsystems. During system tests, while distributing 1.3 GHz signal over 20 km distance, long term signal phase stability (12 h measurement duration) of 3° (6 ps) and short term signal phase stability of 0.35° (0.7 ps) have been achieved.

4

Erythrocyte surface modification due to the pharmacological treatment studied with atomic force microscopy

Targosz M., Czuba P., Szymoński M.

Optica Applicata

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2002

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Vol. 32, nr 3

275-281

EN

The influence of some selected pharmacological compounds on the surface structure of human erythrocytes (red blood cells, RBCs) has been studied by means of atomic force microscopy (AFM). The imaging has been done both in the air environment on the fixed cells, and in a liquid (physiological conditions). RBCs are very sensitive to the osmotic changes in the solution, e.g., increasing NaCl concentration in the solution to a value higher than 0.9% leads to the characteristic changes of the erythrocyte from a discoid-like shape to a very irregular one, the so-called “echinocyte”, with a lot of ledges. Both contact and non-contact AFMs have been used to monitor the consecutive stages of RBC surface modification. Imaging the echinocytes immersed in isotonic solution has shown that the changes in RBC cells are fully reversible in the whole range of concentrations used in this investigation. Furthermore, the modification of the erythrocyte surface morphology induced by nifedipine, a drug used in the pharmacological treatment of hypertension, has been studied in this work.

5

Modyfikacja powierzchni w procesie elektronowo symulowanej desorpcji

Such B., Kołodziej J., Krok F., Meisel K., Czuba P., Piątkowski P., Struski P., Szymoński M.

Elektronika : konstrukcje, technologie, zastosowania

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2001

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Vol. 42, nr 8-9

48-50

EN

Alkali halide surface modification due to electron irradiation was investigated with the use of dynamic force microscopy (DFM) and quadrupole mass spectroscopy (QMS). As a result of desorption of atoms from the surface, rectangular pits are created in the topmost layer of the crystal. During irradiation the pits are growing and linking with others what leads to layer-by-layer desorption. Desorption yields of both components exhibit oscillatory dependence on the dose of impinging electrons. Moreover, a correlation has been found between the number of low-coordinated sites on the surface and desorption efficiency. The model is proposed, in which the phenomenon is explained by creation of dynamic equilibrium between competitive processes: (i) desorption and recombination of pairs of defects and (ii) accumulation of F centres in proximity of the surface, which is directed by the topography of the surface.

6

Nanoscale studies of electron-stimulated desorption of alkali halides

Szymoński M., Kołodziej J., Struski P., Such B., Czuba P., Piątkowski P.

Electron Technology

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2000

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Vol. 33, No. 3

369-374

EN

Electron-stimulated desorption processes of alkali halides have been studied with nanoscale resolution techniques allowing for microscopic understanding of ejection and surface modification mechanisms in those materials. Over the two recenty years, new experimental data were obtained for NaCl, KCl, and KBr nanometer thin films epitaxially grown on GaAs (001) and InSb (001) substrates. Well characterized surfaces were desorbed with 1 keV electrons of various dose and current density. The ejected species were analysed with a mass selected time-of flight spectrometer. We have measured the absolute yields for both alkali and halogen atom components of desorption as well as their translational velocity distributions as a function of the film thickness in the range from 1 to 100 nm. It was found that both the fast and the slow (thermal) components of desorption were strongly thickness dependent due to diffusion mechanisms involved in the transport of the primary excitation products from the bulk to the surface. Topographic features of the modified bulk single crystals of KCl (001) and KBr (001) were observed with an UHV non-contact atomic force microscope (NC-AMF). Rectangular holes of monolayer depth with edges oriented along the main crystallographic directions of the (001) plain were visible on the irradiated surfaces. We found that ESD of alkali halides studied in this work essentially occurred in layer-by-layer mode, except for the fact that the erosion of the consecutive layer started before the erosion of the previous one was completed. The average desortion rates were determined quantitatively from our microscopic data and they were compared with the ones obtained from thin film experiments.

7

Atomic force microscopy imaging of the paper surface subjected to process of artificial ageing

Krok F., Piątkowski P., Czuba P., Konieczna A., Barański A., Szymoński M.

Electron Technology

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2000

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Vol. 33, No. 3

361-365

EN

The influence if the ageing process on the paper surface topography has been examined by means of the Atomic Force Microscopy (AFM). The AFM images of thr native and artificially aged paper exhabit different surface strucure and various abilities to bond water. The surface of native paper consist of the cellulose macrofibres with a spine-like structure, and the elementary fibres of about 10 ÷ 20 nm in diameter. It was found that the ageing process did not change the spine-like structure of the cellulose macrofibres, although it induced the swelling of the elementary fibres. In addition, the images of the aged paper showed that multilayers of water were formed on its surface whereas for non-aged samples such effect was not observed. This behaviour was confirmed by using a technique of "phase-imaging". We argue that swelling of the cellulose fibres and formation of water multilayers is caused by water molecules which are permanently bound to the cellulose chains of the aged paper.