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Publications from the year 2012
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Connecting orbits for a periodically forced singular planar Newtonian system
- Marek Izydorek
- Joanna Janczewska
W niniejszym artykule badamy problem istnienia i krotności rozwiązań homoklinicznych i heteroklinicznych dla nieautonomicznych układów Newtonowskich na płaszczyźnie z potencjałem okresowym ze względu na zmienną czasową, mającym maksimum globalne właściwe przyjmowane w dwóch punktach płaszczyzny i punkt osobliwy (studnię nieskończonej głębokości), w otoczeniu którego potencjał spełnia warunek Gordona (gradient potencjału ze względu na zmienną przestrzenną jest silną i okresową siłą, ang. a periodic strong force). Stosujemy metody wariacyjne i argumenty geometryczne związane z pojęciem i własnościami rotacji.
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Contaminants in airport runoff water
- Anna Sulej-Suchomska
Despite the many positives ensuing from the rapid expansion of the air transport sector, airport operations as a whole are a substantial source of environmental pollution.Increases in aviation developments have serious consequences on the surrounding air, soil and water bodies like lakes, rivers and ground water. The present work deals with the determination of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) found inairport runoff waters from the Lech Walesa Airport in Gdansk. The results of the analyses of runoff water samples from these locations are an excellent qualitative and quantitative index ofcontaminants produced as a result of all kinds of activities at both airports. Analysis of the contaminants present in samples of airport runoff waters provides a clearer picture and understanding of the xenobiotic cycle in the environment. It is therefore crucial that samples of runoff waters from airports should be monitored and analysed for the largest possible number of contaminants.
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Contaminants in airport runoff water in the Vicinities of Two International Airports in Poland
- Anna Sulej-Suchomska
- Żaneta Polkowska
- Jacek Namieśnik
The general aim of the study was to evaluate environmental quality associated with the operations (combustion of fuels, cleaning of aircraft and airport aprons, aircraft, ground vehicle maintenance and repairs, fuelling operations, de/anti-icing operations) of international airports located in central and northern of Poland. These two monitoring areas were set up to monitor PAHs, PCBs, formaldehydes, phenols, detergents (cationic, anionic, non-ionic), metals and other compounds, cations (Ca2+, Mg2+, K+, Na+, NH4+, Li+) and anions (F-, Cl- Br-, NO2-, NO3, PO43-, SO42-, CN-), as well as pH, conductivity and total organic carbon (TOC). The paper presents the results obtained during three years (2008-2011) in storm water events in winter. The results of these studies of runoff water samples can be treated as a basis for evaluating the influence of airports on the environment.
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Context Search Algorithm for Lexical Knowledge Acquisition
- Julian Szymański
- Włodzisław Duch
A Context Search algorithm used for lexical knowledge acquisition is presented. Knowledge representation based on psycholinguistic theories of cognitive processes allows for implementation of a computational model of semantic memory in the form of semantic network. A knowledge acquisition using supervised dialog templates have been performed in a word game designed to guess the concept a human user is thinking about. The game, that has been implemented on a web server, demonstrates elementary linguistic competencies based on lexical knowledge stored in semantic memory, enabling at the same time acquisition and validation of knowledge. Possible applications of the algorithm in domains of medical diagnosis and information retrieval are sketched.
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Contour Analysis of Bleeding Regions in Endoscopic Images
- Adam Blokus
- Adam Brzeski
- Jan Cychnerski
This paper investigates the problem of detecting bleeding regions in images acquired from endoscopic examinations of gastrointestinal tract. The purpose is to identify the characteristic features of bleeding areas' contours in order to develop an accurate method for discriminating between true bleeding regions and missed detections, which could lead to a significant reduction of the false alarm rate of existing blood-detection algorithms. The research was carried out on a set of 40 unique images representing clear, bleeding regions, supplemented with precise markup of bleeding areas drawn by a physician. Another 40 images without blood presence were used, from which non-bleeding regions were acquired by gathering incorrect detections of an exemplary blood- detection algorithm. The contours of both types of regions were analysed by extracting the image area within a given distance from the region border. For describing the nature of the contours, Canny edge detector was used along with several statistical measures. The most descriptive feature enabling discrimination between true and false bleeding areas was identified. Finally, the possibility of utilization of the discovered relations for improving existing blood- detection algorithms is investigated and a method of their application is presented.
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Convenient synthesis of 3-phosphono-β-lactams through the cyclization ofN-alkenyl-phosphonoacetamides
- Paweł Punda
Oxidative cyclization through the treatment by the transition metals is convenientsynthetic tool with a great number of applications. In the most cases the result is the formationof C-C bond between generated radical and unsaturated part of the same or another molecule.As it was presented by Trogolo it is also suitable way to obtain 4-membered heterocyclicβ-lactamic ring[1]. In this communicate we want to present new application of mentionedabove method. It is possible to obtain undescribed so far 3-phosphono-β-lactams through theradical cyclization. N-alkenyl-phosphonoacetamides in presence of manganese(III) acetategives β-lactam ring substituted with phosphono group in the third position. In the preliminarystudies we obtained desired products. However, this method requires further work, from theone side to increase yields and from the other side to check substrate spectrum that reacts inthe same manner.The prepared compounds could have interesting activities in order to structure similarity withβ-lactam antibiotics.
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Conventional and advanced bending strength analysis of common and castellated, homogeneous and hybrid I-beams
- Jacek Chróścielewski
- Zbigniew Cywiński
- Arkadiusz Sitarski
Analiza wytrzymałości na zginanie belek dwuteowych
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Convergence of expansions in Schrödinger and Dirac eigenfunctions, with an application to the R-matrix theory
- Julia Stasińska
W pracy zbadano właściwości rozwinięć w szeregi funkcji własnych dla zagadnień Schrödingera i Diraca. Potwierdzono obserwacje poczynione wcześniej przez Rosenthala oraz przez Szmytkowskiego i Hinze, że szereg funkcyjny występujący w teorii R-macierzy dla cząstek Diraca w ogólności nie zbiega do funkcji ciągłej.
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Convergence of rational multistep methods of of Adams-Padé type
- Magdalena Maria Łapińska
- Winfried Auzinger
Rational generalizations of multistep schemes, where the linear stiff part of a given problem is treated by an A-stable rational approximation, have been proposed by several authors, but a reasonable convergence analysis for stiff problems has not been provided so far. In this paper we directly relate this approach to exponential multistep methods, a subclass of the increasingly popular class of exponential integrators. This natural, but new interpretation of rational multistep methods enables us to prove a convergence result of the same quality as for the exponential version. In particular, we consider schemes of rational Adams type based on A-acceptable Padé approximations to the matrix exponential. A numerical example is also provided.
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Convergence to equilibrium under a random Hamiltonian
- Fernando G.s.l. Brandao
- Piotr Ćwikliński
- Michał Horodecki
- Paweł Horodecki
- J.k. Korbicz
- Marek Mozrzymas
We analyze equilibration times of subsystems of a larger system under a random total Hamiltonian, in which the basis of the Hamiltonian is drawn from the Haar measure. We obtain that the time of equilibration is of the order of the inverse of the arithmetic average of the Bohr frequencies. To compute the average over a random basis, we compute the inverse of a matrix of overlaps of operators which permute four systems. We first obtain results on such a matrix for a representation of an arbitrary finite group and then apply it to the particular representation of the permutation group under consideration.
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Conversion of a diesel engine bus into a trolleybus
- Mikołaj Bartłomiejczyk
- Jarosław Dombrowski
- Marcin Połom
- Olgierd Wyszomirski
Przedsiębiorstwo Komunikacji Trolejbusowej w Gdyni od 2004 roku we własnym zakresie buduje trolejbusy w oparciu o nadwozia używanych autobusów. W monografii przedstawiono przyczyny rozpoczęcia tego przedsięwzięcie, jego przebieg oraz techniczny budowy trolejbusu w oparciu o nadwozie autobusowe.
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Coordination of generator transformer controller and multi-parameter generator controller regulation algotrithms
- Artur Zbroński
- Robert Małkowski
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Correlation between shape errors in flat grinding
- Mariusz Deja
W pracy przedstawiono wyniki badań eksperymentalnych i symulacyjnych związanych z wpływem błędów kształtu narzędzia na błędy ksztaltu przedmiotu szlifowanego w układzie docierarki jednotarczowej. Szlifowanie realizowane było z wykorzystaniem specjalnych narzędzi z możliwością regulacji przekroju promieniowego.
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Corrosion-inhibiting effect of Mimosa extract on brass-MM55 corrosion in 0.5 M H2SO4 acidic media
- Husnu Gerengi
- Katarzyna Schaefer
- Ibrahim Sahin
Ekstrakt z mimosy był badany jako inhibitor korozji mosiądzu MM55 przy użyciu Elektrochemicznej Spektroskopii Impedancyjnej oraz techniki polaryzacyjnej. Badania te wykazały, że ekstrakt z mimosy wykazuje właściwości inhibitora anodowego. Własności inhibicyjne badanego ekstraktu rosły wraz ze wzrostem stężenia inhibitora w kwasie, związano to ze wzrostem adsorpcji cząsteczek inhibitora na powierzchni metalu.
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Cost Effective Corrosion and Fatigue Monitoring for Marine Transport Products
- Henryk Bugłacki
- Peter Tscheliesing
- Andreas Jagenbrein
- Ireneusz Baran
W artykule omówiono genezę i główne założenia projektu badawczego "Cost Effective Corrosion and Fatigue Monitoring for Transport Products'' o kryptonimie CORFAT, realizowanego w ramach VII Programu Ramowego Unii Europejskiej. Przedstawiono cele i metodykę badań, zalety nowej nowej metodyki monitorowania statków, zadania projektu, zalety i ograniczenia metody Emisji Akustycznej (EA), opis innych metod badań nieniszczących (NNDT). Zaprezentowano aparaturę wytworzoną w projekcie oraz przedstawiono wybrane wyniki badań uzyskane podczas prób na statkach.
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Coupled-resonator filters with frequency-dependent couplings: coupling matrix synthesis
- Łukasz Szydłowski
- Adam Lamęcki
- Michał Mrozowski
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Coupled-Resonator Waveguide Filter in Quadruplet Topology With Frequency-Dependent Coupling - A Design Based on Coupling Matrix
- Łukasz Szydłowski
- Adam Lamęcki
- Michał Mrozowski
This letter presents an application of a recently developed coupling matrix synthesis technique to design of coupled-resonator filters with dispersive inter-resonator couplings. This technique is used to design a novel coupled-cavity bandpass filter. Measurements validate the design and confirm effectiveness of the synthesis method. The filter is a four-pole generalized Chebyshev filter with three transmission zeros. Resonators are arranged in a quadruplet configuration and employ a single dispersive cross coupling to produce an extra zero in comparison to classical approaches. Frequency-dependent coupling was realized via a rectangular waveguide iris with an incomplete height conducting post.
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Covalent DNA modification by products of myrosinase catalysed glucosinolate degradation in cell-free system
- Dominik Kołodziejski
- Monika Główczyńska
- Walter Meinl
- Bernhard Monien
- Hansruedi Glatt
- Anna Brillowska-Dąbrowska
- Agnieszka Bartoszek-Pączkowska
The bioactive phytochemicals found in Brassica vegetables belonging to glucosinolates (GLS) and especially the products of their degradation isothiocyanates (ITC) and indoles are regarded as the most promising cancer chemopreventive compounds. These secondary metabolites constitute defence system repelling or preventing the development of agrophages attacking brassica plants. The antibiological properties of these compounds suggest that they may also pose risk for humans when ingested in higher amounts in a form of e.g. dietary supplements. These presumptions have been confirmed by showing mutagenic activity and DNA adduct formation in vitro and in vivo for indoles found in brassica vegetables. Our research concentrated on the ability of degradation products of major aliphatic and indole GLS (AITC, PEITC, sulforaphane, indole-3-carbinol (I3C), indole-3-acetic acid (IAA), indole-3-acetonitril (IAN) and 3,3'-diindolomethan (DIM) a product of I3C dimerization) to induce covalent DNA modification. These mechanistic studies involved both metabolic and kinetic aspects. For this purpose, the restriction analysis method developed by our group was used. This method employs a 695 bp long DNA amplicon that contains two restriction sites: one consisting of only GC base pairs recognized by restriction endonuclease MspI or HpaII and the other consisting of only AT base pairs recognized by the enzyme Tru1I. The modification of the restriction sites abolishes their recognition and thus cleavage by the restriction enzymes. By incubating the DNA amplicon with increasing concentrations of the studied compound(s) in the appropriate activating system (for example sulfotransferases (SULTs) which activate benzylic alcohols), the formation of DNA adducts may be detected and its kinetics monitored. The modified amplicon is submitted to digestion by the mentioned endonucleases and DNA fragments are separated by polyacrylamide gel electrophoresis. The inhibition of cleavage indicates the occurrence of covalent modification of the restriction site(s) simultaneously pointing at the kind of base pairs involved in DNA adduct formation. The restriction analysis demonstrated that some ITC as well as some indole derivatives exhibit the capability of covalent DNA modification.
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Crack propoagation in MgO-PSZ ceramic materials
- Waldemar Karaszewski
The properties of ceramic materials such as elevated hardness, high temperature capability, low coefficient of thermal expansion are of interest for rolling element materials. Widely used ceramic materials in engineering applications are silicon nitride, zirconia and alumina. The paper presents an experimental study of the fatigue life of MgO-PSZ ceramic material in lubricated contact with defined types of cracks. A ceramic angular contact bearing operation was simulated using a four-ball machine. Zirconia balls were artificially damaged with pre-cracks. Ringformed pre-cracks were propagated on the ball surface by a blunt impact load using a tungsten carbide ball under five various impacts. Research of the presented paper shows that fatigue failure under rolling contact loading is markedly sensitive on ringformed pre-cracks made by a different impact energy (drop height). Propagation of surface pre-cracks takes place under a fatigue load. Primary and secondary surface crack propagations are described.
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Creating IT competence centers
- Paweł Madej
This article indicates the need for supporting University Competence Centers. They are specialized centers, which aim to support teaching and development of newest software technologies, educating students, PhD Students and scientific workers also raising competetitiveness of the university at higher education market.