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Repozytorium publikacji
Politechniki Gdańskiej

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Publikacje z roku 2012

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  • The use of bioassays in the analysis of environmental samples
    • Karolina Kuklińska
    2012

    Toxicological tests are increasingly used as effective tool to complement the information obtained during the environmental monitoring. Moreover bioassays provide basic knowledge about the health effects of exposure to harmful factors associated with the environment. Toxicity tests might be a source of information about the content of pollutants in the sample, and the possibility of their interactions. They can be considered as the analytical procedure, which involves observation of changes in the indicator organism due to the presence of contamination in the environment. With the bioassays the overall toxicity of the test system is assessed without indicating which compound is toxic. Only summary effect is important. Toxicity tests should be carried out simultaneously with several indicator organisms that have different sensitivity and represent different trophic levels to obtain reliable results. Bacteria, plants and animal organisms are often used as indicator organism. This paper will describe the most popular bioassays.

  • The Use of Mobile Devices in the Care and Home Monitoring of the Elderly and the Sick
    • Mariusz Kaczmarek
    • Jędrzej Nowak
    • Jacek Rumiński
    • Jerzy Wtorek
    • Tomasz Kocejko
    2012 LECTURE NOTES IN COMPUTER SCIENCE

    ...

  • The use of weight in motion data to heavy vehicles - pavement interaction analysis
    • Dawid Ryś
    2012

    Weight in motion (WIM) is the element of modern intelligent transport systems created to control commercial vehicles and to detect overloaded items. Because all of the vehicles crossing the WIM station are weighed and recognized, given data can be used to vehicle-pavement interaction analysis. The paper presents the results of analysis based on data from seven WIM stations localized in Motorway and National Roads in Poland. The effects of different vehicles types, axles configuration and loads distribution are described in the article. Overload vehicles impact is presented too. Other factors like dynamic reraction, road construction, tire pressure etc. are included in the analysis, but not described in detail in the article due to limited space. Traffic assessment is a very important part of pavement design so practical conclusions are given.

  • Theme Park or a Living Space - Contemporary Conditions and Directions in Reurbanization of Historic Districts = Park rozrywki czy przestrzeń życiowa - współczesne warunki i kierunki reurbanizacji dzielnic historycznych
    • Łukasz Pancewicz
    2012

    Artykuł zawiera analizę obecnych trendów rozwoju historycznych śródmieść miast, wskazując zwłaszcza na uwarunkowania społeczno-gospodarcze. Dotyczy to zwłaszcza procesów związanych z ''estetyzacją'' śrómieść czy gentryfikacją. Artykuł wskazuje na procesy reurbanizacji jako inny proces wspierający możliwą oddolną rewitalziację. Artykuł wskazuje na konieczną rolę publicznej interwnecji (np. polityki wynajmu lokali publicznych, realizacji nowych inwestycji i polityki społecznej).

  • Theoretical Design of the Molecular Structure of Bent-Core Mesogens with Large Second-Order Nonlinear Optical Properties
    • Julien Guthmuller
    • BENOîT Champagne
    • Frédéric Perreault
    • Armand Soldera
    2012 Journal of Physical Chemistry C

    ABSTRACT: The first hyperpolarizability of two series of moleculeswith bent-shaped structures has been calculated at the ab initio level.The two series consist of carboxyl derivatives for which somemolecules are known to exhibit banana phases and of their sulfinatehomologues that have not been synthesized yet. The final purpose isto reveal the relevance or not in synthesizing these latter molecules.The strategy is based on reporting the effect of the positions of donorand acceptor groups on the central benzene ring on the structuralparameters and on the first hyperpolarizabilities. It is shown that inthe sulfinate series the larger first hyperpolarizabilities areincompatible with efficient geometrical character while for the carboxyl series, the opening angle between the molecular armsis typical of banana-shaped molecules but the first hyperpolarizability is only slightly enhanced. Calculations thus reveal that thesulfinate series does not need to be synthesized, whereas they show that our approach can be naturally applied to thedevelopment of new bent-shaped molecules for nonlinear optical applications.

  • Theoretical studies of nonlinear generation efficiency in a bubble layer
    • Anna Baranowska
    2012 Pełny tekst Archives of Acoustics

    Celem pracy jest teoretyczna analiza propagacji fal o dużym natężeniu w warstwie z pęcherzykami. Przedstawiono model matematyczny zjawiska w tym omówiono problem wyznaczania prędkości fazowej, współczynnika tłumienia i częstotliwości rezonansowej pęcherzyków. Badano zmiany amplitud pierwszej i drugiej harmonicznej ciśnienia fali odbitej i bieżącej w funkcji grubości warstwy oraz względnej koncentracji pęcherzyków. Rozważano pęcherzyki o różnych promieniach oraz sygnały o różnych parametrach.

  • Therapeutic intervention by the simultaneous inhibition of DNA repair and type I or type II DNA topoisomerases: one strategy, many outcomes
    • Józefa Węsierska-Gądek
    • Andrzej Składanowski
    2012 Future Medicinal Chemistry

    Many anticancer drugs reduce the integrity of DNA, forming strand breaks. This can cause mutations and cancer or cell death if the lesions are not repaired. Interestingly, DNA repair-deficient cancer cells (e.g., those with BRCA1/2 mutations) have been shown to exhibit increased sensitivity to chemotherapy. Based on this observation, a new therapeutic approach termed 'synthetic lethality' has been developed, in which radiation therapy or cytotoxic anticancer agents are employed in conjunction with selective inhibitors of poly(ADP-ribose)polymerase-1 (PARP-1). Such combinations can cause severe genomic instability in transformed cells resulting in cell death. The synergistic effects of combining PARP-1 inhibition with anticancer drugs have been demonstrated. However, the outcome of this therapeutic strategy varies significantly between cancer types, suggesting that synthetic lethality may be influenced by additional cellular factors. This review focuses on the outcomes of the combined action of PARP-1 inhibitors and agents that affect the activity of DNA topoisomerases.

  • Thermal-hydraulic issues of flow boiling and condensation in organic Rankine cycle heat exchangers
    • Jarosław Mikielewicz
    • Dariusz Mikielewicz
    2012 Pełny tekst Archives of Thermodynamics

    W pracy przedstawiono szereg zagadnień cieplno-przepływowych podczas wrzenia i kondensacji w przepływie w wymiennikach ciepła obiegu ORC. Uwzględniono przemiany fazowe. Analizowano zagadnienia stabilności pracy wymienników oraz ich dynamikę

  • Thermodynamic Cycles of Air Microturbine Power Plants Working on Biomass Fuels
    • Krzysztof Kosowski
    • Marian Piwowarski
    • Robert Stępień
    • Wojciech Włodarski
    2012

    The gas turbine engine is modified to work as an air turbine set which consists, in the simplest arrangement, of a compressor, a heat exchanger and a turbine. Air is a working medium for both: the compressor and the turbine. This kind of air turbine set can be applied in power plants working on biomass fuels. In this solution we can burn fuels of varying parameters in the external combustion chamber without any harmful effects on the operation of the air turbine set. The analysis was carried out for different thermodynamic cycles of power plants with air turbines. The variants with regenerators and different cogeneration systems were considered.

  • Thermoplastic polyurethane/(organically modified montmorillonite) nanocomposites produced by in situ polymerization
    • Michał Strankowski
    • Justyna Strankowska
    • Maria Gazda
    • Łukasz Piszczyk
    • Grzegorz Nowaczyk
    • Stefan Jurga
    2012 Pełny tekst Express Polymer Letters

    A series of polyurethane nanocomposites were synthesized from thermoplastic polyurethanes (with different hard segment ratios) and two types of organically modified montmorillonites (OMMT) - Cloisite® 10A and Cloisite® 20A. The thermal behavior was examined by non-isothermal thermogravimetry (TG, DTG), Differential Scanning Calorimetry (DSC) and Dynamic-Mechanical Thermal Analysis (DMTA). The results of X-ray analyses showed that the OMMT produced the intercalated polyurethane nanocomposites. It has been proven that the thermal stability and tensile properties of these new systems were higher when the organoclay was present within the polymer matrix. Moreover, these properties depend on both the OMMT loading and the type of gallery cations of the organically modified montmorillonites

  • Thin Layer Deposition Methods in Solid Oxide Fuel Cell Technology
    • Paweł Gdaniec
    2012

  • Thin-walled frames and grids - statics and dynamics
    • Tomasz Mikulski
    • Marcin Kujawa
    • Czesław Szymczak
    2012

    Frames and grids assembled with thin-walled beams of open cross-section are widely applied in various civil engineering and vehicle or machine structures. Static and dynamic analysis of theses structures may be carried out by means of different models, startingfrom the classical models made of beam elements undergoing the Kirchhoff assumptions to the FE discretization of whole frame into plane elements. The former model is very simple but the warping effect, very important for thin-walled members, is not accounted for but the latter onerequires considerable increase in analysis effort. It should be observed that in vicinity of the nodes the stresses and deformations are not in accord with the classical beam theory. To takeinto account theses inconsistency the superelement concept is adopted here and necessary stiffness and mass matrices of the node are derived using the unit-enforced displacement method.It is worthy of noticing that these matrices and in results the warping distribution in the node depends considerably on the structure node construction. The same matrices for the beam membersare obtain on the basis of the classical thin-walled beam theory. The same model can be used in the sensitivity analysis of these structures.

  • Three-wheeled mobile platform powered by LabVIEW at energy performance index
    • Krzysztof Jan Kaliński
    • Cezary Buchholz
    2012 Pełny tekst Pomiary Automatyka Robotyka

    W pracy opisano trójkołową platformę mobilną własnej konstrukcji, zbudowaną i kontrolowaną z wykorzystaniem środowiska LabVIEW. W celu realizacji ruchu platformy oraz zapewnienia jego nadzorowania w czasie rzeczywistym, zastosowano sterownik NI cRIO. Zastosowane równolegle techniki projektowania mechatronicznego, tj. wirtualne prototypowanie, symulacje w trybie HILS oraz szybkie prototypowanie na obiekcie docelowym, umożliwiły uzyskanie optymalnego systemu nadzorowania ruchu platformy mobilnej.

  • Time-domain description of point-source acoustic wavefields as a useful approach in ultrasonic techniques
    • Henryk Lasota
    2012

    In traditional acoustics, field problems are usually treated in the frequency domain, broadband fields being reduced to superposition of harmonic spectrum components. However, this approach is inherently acausal and it is known that in case of arbitrary signals, the distribution-based, time-domain description can be more effective. The present paper is an attempt to expand the time-domain linear systems formalism onto space problems of physical acoustics. Ultrasonic waves in liquids are mostly seen as scalar waves of acoustic pressure accompanied by fluid particle velocity. No waves are considered in which velocity is accompanied by pressure. The paper proves the existence and fundamental role of both waves, presenting two distinct spherical wavefields induced by two kinds of point mechanical disturbances. A detailed phenomenological synthesis of linear acoustic field equations followed by an analysis of their solutions performed directly in the time domain, gives two classes of results, showing that the fields of scalar and vector sources, although formally twin, are much different, especially in the immediate vicinity of sources. This difference should not be neglected in precise ultrasonics.

  • Tinnitus Therapy Based on High-Frequency Linearization Principles - Preliminary Results
    • Tomasz Poremski
    • Bożena Kostek
    2012 Pełny tekst Archives of Acoustics

    The aim of this work is to present problems related to tinnitus symptoms, its pathogenesis, hypotheses on tinnitus causes, and therapy treatment to reduce or mask the phantom noise. In addition, the hypothesis on the existence of parasitic quantization that accompanies hearing loss has been recalled. Moreover, the paper describes a study carried out by the Authors with the application of high-frequency dither having specially formed spectral characteristics. Discussion on preliminary results obtained and conclusions are also con pracy przedstawiono problemy szumów usznych, ich patogenezę, hipotezy dotyczące przyczyny występowania szumów usznych oraz stosowane metody terapii. Dodatkowo przywołano jedną z teorii powstawania szumów usznych opartej na mechanizmie działania układów kwantyzacji. W dalszej kolejności zawarto opis przeprowadzonych badań wykorzystujących mechanizm linearyzacji ultradźwiękowej, przedstawiono dyskusję uzyskanych wyników oraz wnioski.

  • Tmscl as a rate accelerating additive in acylations of amines with 5-(α-amino- α'-hydroxy)methylene meldrum's acids
    • Sławomir Makowiec
    • Karolina Janikowska
    2012 Pełny tekst SYNTHETIC COMMUNICATIONS

    Aspects are presented of the acylation of amines, alcohols and thiols with 5-(α-amino- α'-hydroxy)methylene Meldrum's acids. We placed special emphasis on the acylation reaction of secondary amines with 5-(α-amino- α'-hydroxy)methylene Meldrum's acids, which, due to their basicity, caused problems concerning salt formation with a Meldrum acid derivative. We found that secondary amines, which react at the slowest rate and with a low yield with 5-(α-amino- α'-hydroxy)methylene Meldrum's acid, react quickly and with high yields with the same reagent in the presence 1 to 3 equivalents of TMSCl. Acylation with this derivative of Meldrum acid were optimized for such factors as: reaction temperature, solvent polarity and acidity of the environment. We have prepared a wide range of non-symmetrical malononic acid diamids, esters and thioesters of malonamic acid

  • Toolgraph Design of Optimal and Feasible Control Strategies for Time-Varying Dynamical Systems
    • Zdzisław Kowalczuk
    • Krzysztof Oliński
    2012 Pełny tekst MATHEMATICAL PROBLEMS IN ENGINEERING

    Artykuł prezentuje nową metodę projektowania optymalnych i realizowanych strategii sterowania dla wariantnych procesów dynamicznych. Centralnym ośrodkiem i narzędziem tej metody jest struktura grafu przepływowego reprezentująca istotne właściwości autonomicznej dynamiki danego procesu w przestrzeni czasowo-stanowej, składającej się z elementarnych segmentów. Strukturę tę nazywamy grafem narzędziowym przestrzeni czasowo-stanowej. W zastosowanej procedurze każdemu segmentowi temporalnej przestrzeni stanów przypisany jest węzeł owego skierowanego grafu narzędziowego. Wartości przepływu (wagi krawędzi) są proporcjonalne do kosztu przesunięcia punktu pracy rozważanego dynamicznego procesu pomiędzy centrami przylegających segmentów. Dowolny algorytm optymalizacji dyskretnej może być wykorzystany do wyszukaniu najtańszej ścieżki w tak zdefiniowanym grafie, pomiędzy wierzchołkiem reprezentującym segment, w którym znajduje się punkt początkowy a wierzchołkiem reprezentującym segment, do którego należy punkt końcowy szukanej trajektorii. W takim systemie łatwo można uwzględniać dodatkowe założenia lub dowolne ograniczenia wyrażane za pomocą stref zabronionych dla punktu pracy. Węzły odpowiadające tym strefom są przed optymalizacją usuwane ze struktury grafu narzędziowego.

  • Topological Behaviour of Solutions of Vibro-Impact Systems in the Neighborhood of Grazing
    • Sergey Kryzhevich
    • Marian Wiercigroch
    2012 Pełny tekst PHYSICA D-NONLINEAR PHENOMENA

    The grazing bifurcation is considered for the Newtonian model of vibro-impact systems. A brief review on the conditions, sufficient for the existence of a grazing family of periodic solutions, is given. The properties of these periodic solutions are discussed. A plenty of results on the topological structure of attractors of vibro-impact systems is known. However, since the considered system is strongly nonlinear, these attractors must be very sensitive to changes of parameters of the system. On the other hand, they are observed in experiments and numerical simulations. We offer (Theorem 2) an approach which allows to explain this contradiction and give a new robust mathematical model of the non-hyperbolic dynamics in a neighborhood of grazing.

  • Torsion of restrained thin-walled bars of open constant bisymmetric cross-section
    • Marcin Kujawa
    2012 Pełny tekst TASK Quarterly

    Elastic and geometric stiffness matrices were derived using Castigliano's first theorem, for the case of torsion of restrained thin-walled bars of open constant bisymmetric cross-section. Functions which describe the angles of torsion were adopted from the solutions of thedifferential equation for restrained torsion. The exact solutions were simplified by expanding them in a power series. Numerical examples were taken from Kujawa M 2009 Static and Sensitivity Analysis of Grids. . . 97, GUT Publishing House, and Szymczak C 1978 Engineering Transaction 26 323. Convergence of the solutions was analyzed using the matrices derived for torsion angles, warping, bimoments and critical forces.

  • Toward Mechanosynthesis of Diamondoid Structures: IX Commercial Capped CNT Scanning Probe Microscopy Tip as Nowadays Available Tool for Silylene Molecule and Silicon Atom Transfer
    • Aleksander Herman
    2012 Journal of Computational and Theoretical Nanoscience

    According to K. E. Drexler, advanced mechanosynthesis will employ advanced nanomachines, but advanced nanomachines will themselves be product of advanced mechanosynthesis. This circular relationship must be broken in SPM technology development. In the article, the possibility of use easy available commercial CNT tips to assembly silicon-based intermediate generations of nano-devices is considered. Mechanosynthesis of a target class of silicon-based nano-devices will require molecular tools capable of transferring SiH2 molecules and Si atoms to reaction centers that have binding energy in range of -2.9 ± 0.2 eV and -6.8 ± 0.3 eV respectively. Desirable properties for tools include near exoergic transfer of moieties to these structures; good geometrical exposure of moieties; and structural, electronic, and positional stability. The results of this paper suggest that today available on the marked CNT tips have available properties as tools for silylene molecule and silicon atom transfer into reaction center during positional mechanosynthesis. The surpassing features of the commercial single/double wall caped CNT tips like small tip radii, extreme aspect ratio, excellent wear-out behavior and average binding energy of SiH2 ~ -3.2 eV and Si ~ -6.0 eV make them the ideal tools for building bridge between today SPM technology and future implementation of intermediate silicon-based nanotechnology.