Rozprawy doktorskie (dostęp otwarty)

Permanent URI for this collectionhttps://repo.agh.edu.pl/handle/AGH/43120

Zbiór rozpraw doktorskich bronionych w Akademii i gromadzonych w Bibliotece Głównej AGH jest wyjątkową kolekcją z dziedziny nauk inżynieryjno-technicznych, nierozerwalnie związaną z procesem naukowym i badawczym Uczelni i historią edukacji technicznej w Polsce. Kolekcji rozpraw liczącej obecnie ponad 6000 tytułów, dała początek praca inżyniera górnictwa, późniejszego profesora i Rektora Akademii Górniczo-Hutniczej Witolda Budryka pt. „Ruch podsadzki płynnej w rurociągach zamulaniowych”. W dniu 10 września 1928 r. Senat Uczelni nadał Witoldowi Budrykowi, jako pierwszemu w Polsce, tytuł doktora nauk technicznych z zakresu górnictwa. W kolekcji znajdują się między innymi prace profesorów: Andrzeja Bolewskiego, Henryka Góreckiego, Jerzego Grzymka, Franciszka Nadachowskiego. Wśród nich są rozprawy dostępne online w Repozytorium AGH oraz w sposób otwarty jedynie na terminalach komputerowych w Czytelni Oddziału Zbiorów Specjalnych BG AGH.

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Access status: Open Access ,
Poziomy teras fluwialnych jako zapis ewolucji dolin Kamienicy i Ochotnicy w Gorcach
(Data obrony: 2006) Olszak, Janusz
Wydział Geologii, Geofizyki i Ochrony Środowiska
Seven levels of fluvial terraces, of Pleistocene and Holocene age, are present in the Kamienica and Ochotnica valleys. The oldest terraces date from the Sanian 1 cold stage and they lie at the heights of up to 74 m above the present river channel. The fluvial terraces in the Kamienica and Ochotnica valleys record both, tectonic uplift and Pleistocene climatic oscillations. The presence of strath terraces, some of them of Holocene age, indicates permanent uplift of the area throughout the Quaternary. The valleys were deepening mainly during transitional glacial-interglacial periods, and less intensely during the interglacial-glacial transitions and interglacial periods. Aggradation took place in glacial and partly in interglacial periods. The valleys widened, with formation of the strath terraces, mainly during the interglacial periods. A general tendency to narrowing of the valley bottoms has prevailed since Mezopleistocene time, but not every phase in the evolution of the valleys resulted in narrower valleys bottoms. The average rate of incising for both valleys since middle Pleistocene was calculated at ca. 0.2 mm/year. The rate of incision was greatest at the transitional stages and in Eemian and Holocene. The valleys differed in the amount of incision at individual stages of their evolution and the most distinct difference is marked since the Eemian until now. In this time the lowest part Ochotnica Valley deepened more than twice the value for corresponding part of the Kamienica valley. This seems to be a result of different rates of neotectonic uplift.
Access status: Open Access ,
Własności magnetyczne układów niejednorodnych w modelu Isinga
(Data obrony: 2006) Kawecka-Magiera, Barbara
Wydział Fizyki i Informatyki Stosowanej
W pracy na temat "Własności magnetyczne układów niejednorodnych w modelu Isinga" prezentowane są obliczenia numeryczne niektórych parametrów magnetycznych, takich jak namagnesowanie, podatność i korelacje spinowospinowe, dla układów niejednorodnych opisanych za pomocą modelu Isinga. Przedmiotem pracy było opracowanie narzędzi programistycznych, przeznaczonych do badania charakterystyk w niejednorodnych układach magnetycznych, w oparciu o algorytm symulacji Monte Carlo, przetestowane programów z pomocą dostępnych danych eksperymentalnych i analitycznych i zastosowanie do badania magnetycznych własności układów o różnym stopniu i charakterze niejednorodności. Główne zagadnienia rozważane w pracy można przedstawić następująco: Wyznaczanie przebiegów korelacji spinowo-spinowych w funkcji temperatury dla dwuwymiarowego modelu Isinga i dla szkła spinowego. Wyliczanie zasięgu korelacji spinowo-spinowych w zależności od temperatury w cienkich warstwach magnetycznych. Badanie anizotropii funkcji korelacji w szkłach spinowych i w cienkich warstwach magnetycznych. Analiza wpływu warunków brzegowych na powierzchni cienkiej warstwy na kształt profilu namagnesowania wewnątrz próbki. Obliczenia podatności magnetycznej i magnetyzacji w szkłach spinowych z nieporządkiem węzłów. Badanie wpływu stopnia porządkowania atomowego i rozmiaru ziaren krystalicznych w układach nanokrystalicznych na podatność magnetyczną. Wykazanie możliwości powstania anizotropii jednozwrotowej w stopie podstawieniowym, wygrzewanym w polu magnetycznym.
Access status: Open Access ,
Określanie warunków elektrochemicznego otrzymywania $ZnSe$ z roztworów wodnych
(Data obrony: 2006) Kowalik, Remigiusz
Wydział Metali Nieżelaznych
The II-VI wide band-gap semiconductors are very interesting materials because of their potential application in electronic devices like electroluminescence diodes, lasers or light detectors. They can be used in producing data storage devices, display devices or multijunction solar cells. There are many methods for the preparation of these materials. Electrodeposition has been found to be a very good method to fabricate thin films of compound semiconductors. It is low-cost and simple method with many advantages as: possibility of a deposition on large surface areas (even irregular), and assures precise control of this process by adjusting several parameters. The main goal of this work is to analyze the mechanism and kinetics of the electrosynthesis of zinc selenide by electrochemical process from aqueous solution. The voltammetric, hydrodynamic and electrogravimetric measurements were carried out under following condition: concentration of $ZnSO_{4} \; \; 0,1-0,8 \; mol/dm^{3}, \; H_{2}SeO_{3} \; 0,001-0,008 \; mol/dm^{3}, \; pH=2$, temperature 25-75°C. Subsequently process of deposition was carry out under potentiostatic conditions. The influence of deposition potential, the composition and temperaturę of the electrolyte on the stoichiometry composition and morphology of the obtained deposits were examined.
Access status: Open Access ,
Techniki symulacji agentowej w zastosowaniu do badania procesów cieplnych
(Data obrony: 2006-09-26) Bieniasz, Sławomir
Wydział Elektrotechniki, Automatyki, Informatyki i Elektroniki
The subject of this research is the problems of dynamic, complex systems modeling, in which several processes proceeds at the same time and in the common environment. The essence of the proposed modeling method lies in mapping elementary processes and their interactions, leading to achieving summary effects, that result from concurrent realization of these processes. The suggested idea is based on using the agent approach, where individual agents conduct elementary component actions, giving a result in complex processes occurring in virtual world, represented by this model. The purpose of this work is proving that such approach enables approximate but adequate mapping of the real phenomena, and in consequence predicting their course and introduction of correcting actions (control). The domain of the phenomena being analyzed is thermal processes with a special consideration of the phenomena which appear during cooling and solidification of metal castings. However, the given method is recommendation of modeling and studying a wider class of complex dynamic systems.
Access status: Open Access ,
Mikrostruktura i właściwości biomateriałów tytanowych po obróbce powierzchniowej
(Data obrony: 2006-12-05) Biel, Magdalena
Wydział Inżynierii Metali i Informatyki Przemysłowej
The aim of the study was to determine the influence of surface treatment methods on mechanical and tribological properties of metallic materials applied in medicine. The investigation was performed on titanium and Ti6A17Nb alloy after nitridation under glow discharge and after duplex surface treatment. The last method combines nickel electroless chemical deposition with a glow discharge assisted plasma treatment. Complex, quantitative and qualitative analysis of nano/microstructure of formed layers and bulk materials was carried out. Advanced methods of analytical transmission electron microscopy and atomic force microscopy were applied. Influence of surface treatments on layers topography, microhardness, Young modulus and wear friction resistance was determined. Adhesion of formed layers to bulk materials was estimated as well. The results obtained showed that hard multilayers formed during nitridation under glow discharge and duplex surface treatment significantly improve microhardness and wear resistance of the investigated materials.
Access status: Open Access ,
Uogólniona metoda charakterystyk i własności funkcjonalno-analityczne typu Hopfa-Laxa rozwiązań pewnych nieliniowych równań różniczkowych cząstkowych
(Data obrony: 2007) Prikarpats'ka, Natalâ K.
Wydział Matematyki Stosowanej
W rozdziale 2 zostały przeanalizowane pewne ważne aspekty istnienia powierzchni charakterystycznych związanych z równaniami różniczkowymi cząstkowymi rzędu pierwszego i wyższych. Odpowiednia struktura geometryczna tychże powierzchni charakterystycznych została opisana poprzez pewne specjalne pola wektorowe, skonstruowane zgodnie z zadanymi cząstkowymi równaniami różniczkowymi rzędu pierwszego. Wyniki zostały uogólnione na przypadek równań różniczkowych wyższych rzędów. Geometryczna metoda G.Monge'a, rozwijana w rozdziale 3 pracy, zawiera w sobie możliwości dokładnego badania szerokiej klasy nieliniowych równań różniczkowych cząstkowych. Odpowiednia struktura geometryczna charakterystycznych powierzchni, związanych z cząstkowymi równaniami różniczkowymi rzędu pierwszego i wyższych rzędów może być badana efektywnie w przypadku wykorzystania techniki pól wektorowych na hiper-powierzchniach. Zostały wyprowadzone funkcjonalno-analityczne rozwiązania typu Hopfa-Laxa zagadnień brzegowych oraz początkowych dla szerokiej klasy nieliniowych równań różniczkowych cząstkowych rzędu pierwszego, oraz wyższych rzędów i układów. Jako przykład skonstruowano funkcjonalno-analityczne rozwiązania problemu Cauchy'ego dla nieliniowego równania Burgersa za pomocą dokładnych rozwiązań klasycznego równania liniowego typu Airy'ego. W rozdziale 4 rozprawy został wyprowadzony klasyczny wzór Hopfa-Laxa dla problemu Cauchy'ego i jego uzasadnienie dla klasy funkcji wypukłych i półciągłych z dołu. Rozdział piąty jest poświęcony zagadnieniu znalezienia rozwiązań nieliniowych równań różniczkowych cząstkowych przedstawianych przez postać funkcjonalno-analityczną typu Hopfa-Laxa dla pewnej klasy wielowymiarowych równań Hamiltona-Jacobiego. Szczegółowo zostały opisane podstawowe własności rozwiązań zagadnienia Cauchy'ego na zbiorze funkcji wypukłych i półciągłych z dołu, a także dokonano uogólnienia na szerszą klasę funkcji. Zbadano również kanoniczne równanie Hamiltona-Jacobiego zawężone do sfery, znaleziono jego dokładne funkcjonalno-analityczne rozwiązanie typu Hopfa-Laxa.
Access status: Open Access ,
Badania przesunięcia elektrycznego w wybranych modelach płynów złożowych i skał
(Data obrony: 2007) Krochmal, Janusz Kazimierz
Wydział Wiertnictwa, Nafty i Gazu
An attempt was made at using spectrometer measurements of phase angle ranging between 50Hz and 5MHz. The results were obtained at a research stand with a Japanese measuring equipment HIOKI type 3532 for measuring impedance and its components. Its characteristic feature is the binary shaping of sinusoid voltage. The polarization parameter was proposed to be measured in a strongly polarized environment, value of phase angle $\varphi$ observed between impedance Z and resistance R, defined as phase displacement, i.e. time displacement of electrical signal – electric displacement – related with the inertia of electric charge rotation for a given frequency of electric field. This is a polarization angle. Oil from the refinery Trzebinia, diesel oil, unleaded oil and water distilled 4 times at different $NaCl$ concentration is the basic part of the work about fluids. The issue of uncertainty was worked experimentally. The loose rocks: quartz sand, drilling sand, river sand and clayey rocks, e.g. Bulgarian bentonite, Bentopol and drilling clay were used for modeling. A number of conclusions on the applicability could be drawn, creating bases for patent applications.
Access status: Open Access ,
Methods of contour compression in time and spectral domains
(Data obrony: 2007) Ukasha, Ali Abdrhman M.
Wydział Elektrotechniki, Automatyki, Informatyki i Elektroniki
Detailed analysis of the methods for contour data extraction has been given including the comparison between them using the number of operations versus the number of edges of the contour. The results approve that the fastest algorithm is the one which has the smallest size of windows. Six algorithms for contour data approximation in the time domain were proposed (centroid and segment distances ratio algorithms and triangle family which contains four algorithms), and compared with well known Ramer algorithm using mean square error, signal-to-noise ratio, compression ratio and the number of operations. Ali algorithms give CR more than 95% (the triangle family gives more than 97%). Except the first algorithm, their computational time of the approximating procedure is very short (i.e. many times faster than that of Ramer). Three algorithms for contour extraction (using high-pass filter) and image compression (using low-pass filter) using PHL transform were developed and compared with Sobel and Canny detectors. Two algorithms were presented for image reconstruction by contours extraction. The first algorithm using HPF and double transforms (two 1-dimensional and 2-dimensional PHL transform) while the second using two 1-dimensional PHL transform and only the most significant bit of the image.
Access status: Open Access ,
Analiza porównawcza modeli powstawania stożków wodnych w złożach gazowych
(Data obrony: 2007) Smulski, Rafał
Wydział Wiertnictwa, Nafty i Gazu
Exploitation of natural gas fields with edge or underlying water is usually defined per analogy to the oil fields. The existing models do not correspond to reality as they do not describe relevant processes related with a turbulent gas flow near the well. The natural gas exploitation with productivity greater than critical may be advantageous in view of summaric depletion and rate of depletion. The author of the PHD dissertation formulated a thesis stating that natural gas exploitation should be carried out rationally, at a rate higher than critical; it defined as maximum rate which does not cause a dislocation of the gas-water contour in the vicinity of the well. The thesis has been proved through; the analysis of the existing critical rates models, determining the influence of specific parameters on the critical rates values, introducing new modified formula for critical rates, and comparative calculations for various configurations with the numerical models. The thesis is closed with conclusions from the investigations.
Access status: Open Access ,
Wykorzystanie specjalizowanych architektur sprzętowych do realizacji krytycznych czasowo zadań sterowania
(Data obrony: 2007) Piątek, Paweł
Wydział Elektrotechniki, Automatyki, Informatyki i Elektroniki
A control of dynamic systems with controllers developed using special hardware architectures based on FPGA circuits was described in this PhD thesis. Two main hypothetical proposition were formulated:Application of controllers developed using special hardware architectures can substantially improve control quality of dynamic systems. There is possible to realize a number of classical and advanced control algorithms with usage of specialized programmable circuits. Concept of "relatively fast plant" was introduced in the thesis. It means that the relative speed of the plant dynamics was defined with reference to reaction time of control system. A computational systems that can provide control for fast plants was described. The PhD thesis contains description of selected digitization methods and selected methods providing realization of linear SISO controllers. Discussion was illustrated by example of PID controllers. The magnetic levitation system was chosen as example of a relatively fast plant. A number of experiments were performed with this plant and its mathematical model. Experiments were provided with usage of three type control systems: PC computer, microcontroller based and the last one based on FPGA circuit. The obtained results of experiments has justified the theses
Access status: Open Access ,
Analiza akustycznych obrazów falowych w aspekcie zwiększania informacji o parametrach sprężystych i zbiornikowych skał
(Data obrony: 2007) Wawrzyniak, Kamila
Wydział Geologii, Geofizyki i Ochrony Środowiska
PhD thesis presents application of time-frequency methods to acoustic full waveforms (AFW) processing. The goals of the research are: precise determination of acoustic waves from AFW, wave field decomposition into separate waves and pointing out zones of different elastic parameters. First part of the thesis includes: theoretical background of time-frequency methods, information on full waveform acoustic logs and brief description of the data. Second part is devoted to detailed description of time-frequency analyses of acoustic full waveforms. Discrete and continuous wavelet transform and matching pursuit algorithm are applied to AFW. Simulations, methodology and results of each method are discussed in detail. From proposed methods matching pursuit reveals the best resolution and makes wave extraction possible. Results are used for transit interval time calculation, which are compared with the counterpart parameters obtained from the original waveforms (i.e. not decomposed with matching pursuit). Additionally, decompositions are used for determination of frequency content of each wave packet. Time-frequency representations of AWF are also used to improving qualitative interpretation. On the basis of continuous wavelet transform time-depth-frequency plots for a given frequency are constructed. What is more, continuous wavelet transform and matching pursuit decomposition are used to calculating instantaneous attributes that indicate local changes of geological formation. Presented research is a kind of methodological work. Developed procedures are innovative and universal.
Access status: Open Access ,
Ocena wpływu pozatorakalnych dróg oddechowych na oddechową impedancję wejścia
(Data obrony: 2007) Latawiec, Wojciech
Wydział Elektrotechniki, Automatyki, Informatyki i Elektroniki
During the assessment of resistive properties of the respiratory system it is adviced that the patent supports his/her cheeks with palms,. This is made to minimize the influence of extrathoracic airways on the measurements of input respiratory impedance (Zin). Upper airway impedance (Zuaw) can seriously influence the measurements of input impedance (and respiratory system impedance), and supporting the cheeks increases Zuaw, thus minimizing its influence on Zin measurements. Knowing Zuaw -makes possible the correction of Zin. To prove that thesis following actions were undertaken: Measurements of input impedance in different setting were made. A special mask has been designed to allow measurements with the helmet and cheeks supported, which allowed the calculation of Zuaw and its comparison to the impedance obtained during Valsalva maneuver with cheeks supported. Mean values of impedances Zuaw, ZuawSTP, Zval, ZvaISTP were used to ąuantify the influence of Zuaw on Zin. Models of Zuaw have been proposed, which yielded to assessment of extrathoracic airways properties and evaluation of the influence of supporting the cheeks on Zuaw models' parameters. A correction of Zin with the calculated values of Zuaw has been performed.
Access status: Open Access ,
Sieciowy system agentowy w geoinformatyce obrazowej
(Data obrony: 2007) Twardowski, Mariusz
Wydział Geodezji Górniczej i Inżynierii Środowiska
Thesis constitutes an attempt to develop method of using mobile agent system for searching and acqire imagery data, from sparse database over Internet, for the purpose of photogrammetry. It includes description of current network protocols and methods of sharing geodata used so far. Furthermore aplied mobile agent system and set of complementary written programs were presented, as well as photogrammetry basics for algorighms of those programs. Last part of thesis was dedicated to critilcal evaluation of correctness, efficiency and uniqueness of designed method. All stages of project were made with open source software. Research has proved that agent system in connection with other network transmission methods can be sucessfully used as means to obtain imagery data. Sparse database may contain aerial photos, but due to modular architecture of system its easy to expand it to support other kind of images. It's been estabilished, that thanks to designed method, time of aquiring data has reduced and realibility of data access has improved, when compared to traditional methods.
Access status: Open Access ,
Estymacja częstotliwościowych parametrów systemu elektroenergetycznego z zastosowaniem koherentnego repróbkowania
(Data obrony: 2007) Borkowski, Dariusz
Wydział Elektrotechniki, Automatyki, Informatyki i Elektroniki
The coherent resampling method of power system signals is presented in the dissertation. The method allows to decrease DFT leakage as well as to decrease errors of power system frequency parameters estimation. The operation of the method insists on continuous approximation of samples of the signal and then calculation of the approximating function at selected resampling time moments. Approximation and resampling are realized by means of digital filtering. Resampling moments are determined using estimated fundamental freąuency of the power system. Fundamental frequency is traced by extended Kalman filter. The dissertation consists of following parts: introduction and motivation of research filed choice selected matters of power system modeling and diagnostics as well as description of selected measurement techniques theory concerning approximation, resampling and frequency estimation problems detailed description of the proposed method real-time implementation of coherent resampling algorithm on Digital Signal Processor simulation and experimental experiments results, which confirm effectiveness of the method summary, original parts of the dissertation, further research directions.
Access status: Open Access ,
Opracowanie algorytmów komputerowej analizy obrazu do identyfikacji klas nieciągłości obserwowanych na mikroskopowych obrazach struktur skalnych
(Data obrony: 2007) Obara, Bogusław
Wydział Elektrotechniki, Automatyki, Informatyki i Elektroniki
The methods currently applied for the analysis and processing of digital images do not satisfy the specific requirements connected with the task of identification of selected discontinuity classes occurring in microscopic rock images, whereas this very type of analysis is particularly important in the context of applications of the computer analysis of images for the purpose of assessing the geomechanical properties of these rocks. The present paper contains research into new IT tools that enrich the assortment of available computer image analysis techniques. It sets forward new algorithms for the computer analysis of images, which lead to the fully automatic identification of selected discontinuity classes occurring in microscopic images of rock structures. The study, concerned with new techniques for assessing the properties of rocks using computer image analysis and processing, contains inter alia: the elaboration of a methodology for identifying selected discontinuity classes, a selection of criteria for the optimal selection of the colour model for the identification of selected discontinuity classes, the elaboration of algorithms for the automatic identification of selected discontinuity classes (taking into consideration non-coloured microscopic images and images obtained using colouring substances), the execution of the process of verification and analysis of the proposed algorithms. Basing on the results obtained, it was determined that it is possible to effectively use the image analysis method for the completely automatic identification of selected discontinuity classes in selected rock structures observed using a polarising optical microscope, both with and without the application of colouring substances. The scientific result obtained may have considerable practical significance, for it enables the automation and objectivisation of microscopic analyses of formulations frequently prepared in connection with research into the properties of rocks.
Access status: Open Access ,
Organizacja struktury bazy danych topograficznych do automatycznej generalizacji kartograficznej
(Data obrony: 2007) Szostak, Marta
Wydział Geodezji Górniczej i Inżynierii Środowiska
This Doctoral Thesis addresses primarily concerning modification of the Topographic Database structure in order to ensure automatic execution of selected cartographic generalization processes enabling visualization of topographic maps content in any scale. In relation with the abovementioned aspect, a proposal for triple layered architecture of Topographic Database management system has been put forward. The system relies upon the Topographic Database modified into a MRBD type source database of a proper structure that enables application of algorithms from the application server (second layer of the system). The server features algorithms for performance of a variety of generalization procedures in accordance with objective and user-independent principles. These algorithms include mainly the following: classification, elimination, simplification and object aggregation; conflict elimination and determination of the method for visualization of objects on the map. In order to determine the structure of the Topographic Database, a variety of concepts for its creation as MRDB type database have been evaluated. Detailed conditions enabling application of specified generalization operators have been also applied in the structure. In order to verify that Topographic Database management system functions correctly, generalization procedures have been carried out for selected super-classes of objects of the database in question. In this way, correctness of modification of the Topographic Database structure and proper interaction between the user interface (third layer of the system) with the application server have been verified.
Access status: Open Access ,
Badania wpływu sprzęgła hydrodynamicznego o stałym napełnieniu na pracę napędu koła czerpakowego na przykładzie koparki SchRs 800
(Data obrony: 2007) Szepietowski, Michał
Wydział Inżynierii Mechanicznej i Robotyki
Digging force of the bucket wheel has stochastic character. The biggest its value, being able to lead to the serious breakdown, appears in the moment of coming across the undiggable boulders. Therefore different kind of overload safety devices are applied in the drive of the bucket wheel. The fluid coupling is one of them, used very often recently. The problem solved by this dissertation is determining the income of the fluid coupling to the quality of the bucket wheel drive functioning. It was made on the example of the modernized bucket while drive of the SchRs 800 excavator, by comparing behavior of the drive with the fluid coupling installed and without it in all sorts states of work. Computer simulation is the only way to make such comparison. There is mathematical model of bucket while drive and its sub-assembles presented. Values of parameters basing on a specification sheet of the drive are given. Models of digging force of the bucket wheel in different states of work are elaborated. Tuning of the unknown values of model parameters is made basing on time characteristics measured on the SchRs 800 excavator in exploitation conditions. The dissertation contains the results of these simulation research and following them conclusions. The most important conclusion is, that fluid coupling reduces dynamic overload of the drive sub-assembles during the stress stop of the while.
Access status: Open Access ,
Modelowanie ulotu elektrycznego dla analizy warunków eksploatacyjnych wysokonapięciowych układów elektroenergetycznych
(Data obrony: 2007) Tarko, Rafał
Wydział Elektrotechniki, Automatyki, Informatyki i Elektroniki
The Ph.D. thesis refers to the coordination insulation in high and extra high voltage power systems. One of the main components of coordination insulation is estimation of the surge hazards expected to appear during the exploitation. The analysis focused on the estimation of the overvoltages caused by lightning strokes, because their crest values significantly exceeds the highest voltage for equipment. The mechanism of lightning surges results from complex nonlinear and wave effects occurring in the power system. One of these phenomena is corona, which decreases crest value and front steepness of the overvoltage waves propagating in the transmission lines. The Ph.D. thesis presents issues connected with computer modelling of the high and extra high voltage power systems for the lightning surges. It also contains a description of power systems mathematical models, elaborated for the simulation of overvoltage waves propagation, taking into account corona from conductors of an overhead line. The Electromagnetic Transients Program in an Alternative Transients Program version was used for the software-based execution of models. The computer simulation results of surge hazards effected by direct lightning stroke to transmission lines are presented in the Ph.D. thesis. The obtained results may be used for the verification and specification of high and extra high voltage power systems designing and exploitation.
Access status: Open Access ,
Ocena przydatności wybranych modeli gaussowskich w obliczeniach stanu zanieczyszczenia powietrza
(Data obrony: 2007) Szczygłowski, Przemysław
Wydział Geodezji Górniczej i Inżynierii Środowiska
The explanation of the thesis, that the appropriate air pollution dispersion models' parameters facilitate the optimization of calculation of the immission, was the main purpose of this paper. The studies was based on the Gaussian puff model (CALMET/CALPUFF) analysis. Theoretical part consists of model parameters and their influence on air pollution dispersion. Methodology applied in statistical assessment of the studies outcomes was described in second section of the theoretical part of paper. Research part's aim was an extension and verification of data appearing in specialist literature, in these aspects of air pollution dispersion calculation that have significant influence on the calculation results. With respect of research findings' analysis and specialist literature data, there was an author's expert system developed (application "optymalizacja"). The application supports the choice of appropriate options of CALMET/CALPUFF model dependently on the input parameters and user's expectations.
Access status: Open Access ,
Wpływ technologicznych parametrów napawania brązu na podłoże stalowe na wybrane właściwości użytkowe napoin
(Data obrony: 2007) Góral, Tomasz
Wydział Inżynierii Mechanicznej i Robotyki
The influence of the selected parameters pad welding by the MIG method of the tin bronze CuSn6 pad welding on the difficult - to - weld steel (steel type 45) on the chosen properties of welds was discussed. The investigations ware made to determine the ranges of the technological parameters of the padding which guaranteed an adequate quality of the welds. Using mathematical planning of experiment showed the influence of the technological parameters of the padding on the geometry of the bronze layer. The influence of the selected parameters of the tin bronze pad welding on steel on the chosen properties of welds also was discussed. The technological parameters were held constant during the padding which guaranteed an adequate quality of the welds and a small base material fraction for investigations usable properties. The influence of the pitch of runs was definited during investigations on the geometry of the bronze layer. Hardness was assigned for padding welds, the base material and the zone between padding weld and base material. Detection of possible internal defects of padding welds was the aim of metallographic and X-ray radiography investigations of welds. The bend test was used to assess the level of the weld adhesion to the base material. The hardness investigations showed the influence of the number of bronze layers on their hardness. The essential influence of the surfacing process on the hardness of the base material was not found. The normal bend test showed the good adhesion of the surfacing layer and steel. The presence of the smali defects did not have the essential influence on the usable properties padding welds. The results of tribological tests of single and two layer CuSn6 bronze welds of padded on the steel base were compared with these for the cast bronze of the same chemical composition. Friction coefficients and linear wear of pairs under sliding were measured for the lubricating environment of mineral and synthetic oils. The investigation revealed the dependence of friction coefficient on the number of layers in the weld pad and on the lubricating environment. Differences were not observed for the linear wear of layered and comparative samples working in the environment of synthetic and mineral oil.