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Publikacje z roku 2013

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  • Kształtowanie charakterystyk sieci radiokomunikacyjnych w technologii radia kognitywnego
    • Małgorzata Gajewska
    2013

    W artykule przedstawiono koncepcję radia kognitywnego, jako technologii przyszłości komunikacji radiowej. Następnie omówiono cykl kognitywny. Ponadto zaproponowano zastosowanie algorytmu sztucznej inteligencji, znanego pod nazwą „algorytm symulowane wyżarzanie”, do zastosowania w radiu kognitywnym, w celu zwiększenia efektywności jego działania przez odpowiednie kształtowanie charakterystyk sieci radiokomunikacyjnych.

  • Kształtowanie poziomu płynności w bankach komercyjnych w Polsce w warunkach kryzysu
    • Anna Rzeczycka
    • Gabriela Golawska-Witkowska
    2013 Prace Naukowe Wyższej Szkoły Bankowej w Gdańsku

    W publikacji przeprowadzono analizę kształtowania się poziomu ryzyka płynności w bankach komercyjnych w kontekście obowiązujących regulacji prawnych.Określono miejsce płynności w celach działalności banków. Dokonano przeglądu regulacji ostroźnościowych, dotyczących płynności oraz określono sytuację płynnościową banków w Polsce.

  • Kunst am Bau Orońsko 2013
    • Dąbrówka Tyślewicz
    2013

  • Laboratory assessment of permeability of sand and biopolymer mixtures
    • Mateusz Wiszniewski
    • Skutnik Zdzislaw
    • Ali Firat Cabalar
    2013 Annals of Warsaw University of Life Sciences-SGGW Land Reclamation

    Laboratory assessment of permeability of sand and biopolymer mixtures. This research presents a method of creating seepage barriers in a sandy soil using biopolymer additives (biosubstance), which consist of polysaccharides and water. Polysaccharides strongly interact with water to produce a viscous suspension. The paper aims to investigate the infl uence of a biosubstance employed in a highly permeable sandy soil. Amount of the biopolymer used in a sample were 0.5, 1.0 and 1.5%, by dry weight. The test results indicate that the hydraulic conductivity signifi cantly decrease with the amount of biosubstance added but only slightly increase when curing time gets longer. It is thought that such application, which is a relatively new soil improvement technique, could be used as a seepage barrier installation required to protect some geotechnical works including foundation, underground structures and waste disposals.

  • Laboratory investigation with subbottom parametric echosounder SES-2000 standard with an emphasis on reflected pure signals analysis
    • Grażyna Grelowska
    • Eugeniusz Kozaczka
    • Sławomir Kozaczka
    2013

    The main goal of the paper is to describe correlations between measurements results of trials taken on Gulf of Gdańsk bottom sounded with parametric echosounder SES-2000 Standard and laboratory research where collected during survey sediments were measured. Stationary tests took place at Gdansk University of Technology where 30 meters long 1.8 meter deep and 3 meters wide water tank is located. Main lobe of antenna was directed parallel to the longest dimension. Hydrophones used during experiment were fixed to the 3D positioning system - ISEL which gave the opportunity to place sensor with high precision in the middle of main lobe or other specified places. Using prepared to this experiment frames different sea bottom layers configurations corresponding to the natural structure were sounded. Data obtained during laboratory measurements and trials in situ were combined to draw conclusions about proper interpretation of echograms and begin the process of sediments classification. Analyzes were done with Matlab programming software were data were imported and used to the simulations and comparisons.

  • LABOUR SHARE IN THE DOMESTIC INCOME COMPARED TO DIFFERENT LABOUR MARKETS
    • Małgorzata Gawrycka
    • Anna Szymczak
    2013 Pełny tekst Przedsiębiorstwo we współczesnej gospodarce - teoria i praktyka

    The purpose of this paper is to examine the changes in the share of labour in the domestic income in the years 1995-2010 in the Visegrád Group states, taking into account the level of development of the domestic labour markets. The study involves a review of the literature relating to the labour market issues, collecting sources and their use in the empirical part. The study used the induction method, the elements of descriptive statistics and taxonomy.

  • Language material for English audiovisual speech recognition system developmen . Materiał językowy do wykorzystania w systemie audiowizualnego rozpoznawania mowy angielskiej
    • Andrzej Czyżewski
    • Bożena Kostek
    • Tomasz Ciszewski
    • Dorota Majewicz
    2013

    The bi-modal speech recognition system requires a 2-sample language input for training and for testing algorithms which precisely depicts natural English speech. For the purposes of the audio-visual recordings, a training data base of 264 sentences (1730 words without repetitions; 5685 sounds) has been created. The language sample reflects vowel and consonant frequencies in natural speech. The recording material reflects both the lexical word frequencies and casual speech sound frequencies in the BNC corpus of approx. 100m words. The semantically and syntactically congruent sentences mirror the 100m-word corpus frequencies. The absolute deviation from source sound frequencies is .09% and individual vowel deviation is reduced to a level between .0006% (min.) and .009% (max.). The absolute consonant deviation is .006% and oscillates between .00002% (min.) and .012% (max.). Similar convergence is achieved in the language sample for testing algorithms (29 sentences; 599 sounds). The post-recording analysis involves the examination of particular articulatory settings which aid visual recognition as well as co-articulatory processes which may affect the acoustic characteristics of individual sounds. Results of bi-modal speech elements recognition employing the language material are included in the paper.

  • Large Hydrodynamic Thrust Bearings and Their Application in Hydrogenerators
    • Michał Wasilczuk
    • Michał Wodtke
    • Leszek Dąbrowski
    2013

    Large hydrodynamic thrust bearings are the bearings which, due to hydrodynamic lubrication, allow large axial load to be transferred from a moving part (shaft) to the stationary part via a thin layer of the lubricant (usually oil), thus providing extremely low friction and practically no wear. Hydrogenerators with vertical shafts are the most important application of large thrust bearings. Main design and scientific problems of large tilting pad bearings, example applications as well as the results of research are described in this encyclopedia entry.

  • Large thermo-elastic displacement and stability FEM analysis of multilayered plates and shells
    • Agnieszka Sabik
    • Ireneusz Kreja
    2013 Pełny tekst THIN-WALLED STRUCTURES

    The paper concerns the load capacity analysis of thermally loaded multilayered plates and shells. The multilayered body is treated as an equivalent single layer whose kinematics is consistent with first order shear deformation theory. The authors focus on the thermo-elastic stability problem of the thin-walled structures. The equilibrium paths are traced with the use of Riks-Wempner-Ramm algorithm. By making use of the Tsai-Wu hypothesis the material's strength examination is included in the study. The considered problems are resolved with the authors' program. The presented results confirm that the proposed model can be very effective in the stability analysis of multilayered panels.

  • Large-scale DFT calculations in implicit solvent-A case study on the T4 lysozyme L99A/M102Q protein
    • Jacek Dziedzic
    • Stephen Fox
    • Thomas Fox
    • Christofer Tautermann
    • Chris-Kriton Skylaris
    2013 INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY

    W ostatnich latach zaproponowano szereg modeli typu implicit solvent, ktore bazują na bezpośrednim rozwiązaniu niejednorodnego równania Poissona w przestrzeni rzeczywistej. Modele te charakteryzują się elegancją, ponieważ wnęka, w której umieszczona jest molekuła substancji rozpuszczanej zdefiniowana jest bezpośrednio w funkcji gęstości elektronowej, a rozkład ładunku jest w sposób samouzgodniony polaryzowany dzięki reakcji dielektryka, który ją otacza.Mimo to, implementacja tego rodzaju modeli jest skomplikowana technicznie i wymaga ostrożności. Również użytkownicy modeli muszą wykazać ostrożność, a to z uwagi na szereg parametrów numerycznych, które muszą zostać odpowiednio dobrane, aby osiągnąć dokładne i fizycznie sensowne wyniki.W niniejszej pracy opisano w których częściach modelu biorą udział odpowiednie parametry oraz w szczegółach zbadano ich wpływ na przebieg obliczeń. Wykorzystano model zaimplementowany w programie ONETEP, realizującym liniowo-skalujące się obliczenia metodą funkcjonału gęstości (DFT). Dzięki temu, że program ONETEP umożliwia prowadzenie obliczeń dla tysięcy atomów, za badany układ przyjęto kompleks 2602-atomowego lizozymu T4 L99/M1012Q. Zbadano wpływ parametrów na energie solwatacji i wiązania, które są istotnymi wielkościami w obliczeniowej optymalizacji potencjalnych leków. Zaproponowano optymalne wartości wspomnianych parametrów, których należałoby użyć w rutynowych obliczeniach.

  • Laser reflectance interferometry system with a 405 nm laser diode for in-situ measurement of CVD diamond thickness
    • Maciej Kraszewski
    • Robert Bogdanowicz
    2013 Pełny tekst Metrology and Measurement Systems

    In situ monitoring of the thickness of thin diamond films during technological processes is important because it allows better control of deposition time and deeper understanding of deposition kinetics. One of the widely used techniques is laser reflectance interferometry (LRI) which enables non-contact measurement during CVD deposition. The authors have built a novel LRI system with a 405 nm laser diode which achieves better resolution compared to the systems based on He-Ne lasers, as reported so far. The system was used for in situ monitoring of thin, microcrystalline diamond films deposited on silicon substrate in PA-CVD processes. The thickness of each film was measured by stylus profilometry and spectral reflectance analysis as a reference. The system setup and interferometric signal processing are also presented for evaluating the system parameters, i.e. measurement uncertainty, resolution and the range of measurable film thickness.

  • Lax-Wendroff and McCormack Schemes for Numerical Simulation of Unsteady Gradually and Rapidly Varied Open Channel Flow
    • Justyna Machalińska-Murawska
    • Michał Szydłowski
    2013 Pełny tekst Archives of Hydro-Engineering and Environmental Mechanics

    Two explicit schemes of the finite difference method are presented and analyzed in the paper. The applicability of the Lax-Wendroff and McCormack schemes for modeling unsteady rapidly and gradually varied open channel flow is investigated. For simulation of the transcritical flow the original and improved McCormack scheme is used. The schemes are used for numerical solution of one dimensional Saint-Venant equations describing free surface water flow. Two numerical simulations of flow with different hydraulic characteristics were performed – the first one for the extreme flow of the dam-break type and the second one for the simplified flood wave propagation problem. The computational results are compared to each other and to arbitrary solutions.

  • LC-MS and LC-NMR as Complementary Techniques for the Determination of Pharmaceuticals in Dosage Formulations
    • Kamila Wilczewska
    • Agata Kot-Wasik
    • Jacek Namieśnik
    2013 CRITICAL REVIEWS IN ANALYTICAL CHEMISTRY

    Pharmaceuticals contain not only pharmacologically active compounds but also a range of excipients. The danger exists that impurities may also be present in such drugs, which may adversely affect their efficacy and even endanger patient health and life. Monitoring the composition of pharmaceutical products is therefore essential. The trace amounts of such impurities in pharmaceuticals are often identified and determined with liquid chromatography coupled with mass spectrometry (LC-MS) or with nuclear magnetic resonance spectroscopy (LC-NMR). With the LC-MS technique, compounds known or suspected to be present in the sample can be identified, but this technique is unsuitable for identifying unknown compounds. In the latter case NMR spectra usually provide reliable structural information; in combination with LC, a mixture of impurities can be identified. The simultaneous use of LC-MS and LC-NMR may supply valuable information on the molecular weight and chemical structure of a compound. This article discusses the merits and shortcomings of both methodologies for determining the structures of unknown compounds. The two approaches should be treated as complementary.

  • LC-MS/MS dtermination of isoprostanes in plasma samples collected from mice exposed to doxorubicin or tert-butyl hydroperoxide
    • Monika Janicka
    • Agata Kot-Wasik
    • Agnieszka Bartoszek-Pączkowska
    • Jacek Namieśnik
    2013 Pełny tekst INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES

    Isoprostanes are stable products of arachidonic acid peroxidation and are regarded as the most reliable markers of oxidative stress in vivo. Here we describe the LC-MS/MS procedure enabling simultaneous determination of four regioisomers (8-iso prostaglandin F2α, 8-iso-15(R)-prostaglandin F2α, 11β-prostaglandin F2α, 15(R)-prostaglandin F2α) in plasma samples collected from mice. The four plasma isoprostanes are determined by LC–ESI-MS/MS with deuterated 8-iso-PGF2α-d4 as an internal standard (I.S.). For plasma samples spiked with the isoprostanes at a level of 200 pg/mL each, the method imprecision has been below 7.1% and mean inaccuracy equaled 8.7%. The applicability of the proposed approach has been verified by the assessment of changes in isoprostane levels in plasma samples derived from mice exposed to tert-butyl hydroperoxide (TBHP), a model inducer of oxidative stress, or to antitumor drug doxorubicin (DOX) known for potent stimulation of redox cycling. Compared to the control group of mice, both oxidative stress inducers tested increased the levels of three out of four isoprostanes in exposed animals; 11β-prostaglandin F2α being the exception. The greatest rise was observed in the case of 15(R)-prostaglandin F2α, by about 50% and 70% in plasma samples derived from mice exposed to DOX and TBHP, respectively.

  • Lead(II)-selective ionophores for ion-selective electrodes: A review
    • Marcin Guziński
    • Grzegorz Lisak
    • Justyna Kupis
    • Artur Jasiński
    • Maria Bocheńska
    2013 ANALYTICA CHIMICA ACTA

    In potentiometry, high selectivity of the ion-selective membranes must be assured in order to reliably measure various analytes in clinical, industrial and environmental samples. Due to the toxic nature of lead(II) it is important to monitor Pb2+ distribution in natural waters. This may be achieved by implementation of ion-selective electrodes (ISEs) with high selectivity towards lead(II) and low detection limit. A great number of Pb2+-ionophores were synthesized and studied. In this work lead(II)-selective ionophores, starting from late 90s, are gathered and discussed. This work gives a comprehensive description and discussion on the novel and available lead(II)-selective ionophores for ISEs.

  • Learning design of a blended course in technical writing
    • Iwona Mokwa-Tarnowska
    2013 Pełny tekst Beyond Philology: An International Journal of Linguistics, Literary Studies and English Language Teaching

    Blending face-to-face classes with e-learning components can lead to a very successful outcome if the blend of approaches, methods, content, space, time, media and activities is carefully structured and approached from both the student’s and the tutor’s perspective. In order to blend synchronous and asynchronous e-learning activities with traditional ones, educators should make them inter-dependent and develop them according to instructional design. The writing component of a language course must aim at linguistic accuracy as well as simulated and authentic communication. All linguistic, communicative, general educational aims and single, measurable objectives should be clearly and precisely stated. The content of a course in Technical Writing should depend on students’ needs and must be related to their study fields. If the learning environment is well organised, supportive and responsive, it provides good conditions and plenty of opportunities for personal growth and development of language skills.

  • Lekka szczelna studzienka z tworzyw, lub wręcz plastikowa – stereotypy w projektowaniu kanalizacji
    • Ziemowit Suligowski
    2013 Pełny tekst Inżynieria Morska i Geotechnika

    Kanalizacyjna studzienka rewizyjna. Stereotypy w projektowaniu i realizacji. Zróżnicowane wymagania w odniesieniu do poszczególnych odmian konstrukcji. Minimalna informacja projektowa. Zabezpieczenie dla inwestora - zapisy w SIWZ. Minimalna informacja handlowa, klasyfikacje normowe

  • Leukemia and risk of recurrent Escherichia coli bacteremia: genotyping implicates E. coli translocation from the colon to the bloodstream.
    • Alfred Samet
    • A. Śledzińska
    • Beata Krawczyk
    • A. Hellmann
    • Stella Nowicki
    • Józef Kur
    • Bogdan Nowicki
    2013 Pełny tekst EUROPEAN JOURNAL OF CLINICAL MICROBIOLOGY & INFECTIOUS DISEASES

    In patients with leukemia, the portal(s) and reasons for the persistence of an Escherichia coli recurrent bacteremia remain unclear. Adult Hematology Clinic (AHC) databases at the State Clinical Hospital in Gdańsk were reviewed to evaluate the frequency of E. coli bacteremia between 2002 and 2005. Blood and bowel E. coli strains were obtained and the genetic relatedness of the strains was analyzed. The rate of E. coli bacteremia per 1,000 admissions at the AHC was higher (85.0) than in the other clinics of the hospital (2.9), p < 0.001. A higher mortality was observed in patients with a history of E. coli versus non-E. coli bacteremia [30/95 (31 %) vs. 53/430 (12 %), p < 0.001]; 72.8 % of patients with leukemia had an unknown source of bacteremia. In 2005, 6 out of 25 (24 %) patients with leukemia had ≥2 episodes of E. coli-positive blood cultures. These gastrointestinal E. coli isolates were replaced within 3–8 weeks with a new E. coli H genotype. A recurrent episode of bacteremia was usually caused by an infection with a transient E. coli H genotype identical to that found in the subject’s bowel. Consistent with the definition of bowel/blood translocation, the bowel appeared to be a portal for E. coli in these subjects and, hence, a clear source for their recurring bacteremia.

  • Ligation Mediated PCR methods, their possibilities and limitations
    • Beata Krawczyk
    • Józef Kur
    2013

    The application of molecular diagnostics for bacterial strain typing or identifying bacteria at the strain level is of particular importance at present. However, among the many genotyping methods that are currently available, no single one is universally ideal. In this article, we thus review the Ligation Mediated PCR group methods as prospects from which to choose. We discuss different strategies for selecting the amplified PCR fragments from the whole-genome by using simple molecular biology tools. Our aim is to present the possibilities and limitations of these methods

  • Linear and branched polyester resins based on dimethyl-2,5-furandicarboxylate for coating applications
    • Erik Gubbels
    • Lidia Jasińska-Walc
    • Bart A. J. Noordover
    • Cor E. Koning
    2013 EUROPEAN POLYMER JOURNAL

    In this study, novel bio-based hydroxyl-functional (co)polyesters from dimethyl-2, 5-furandicarboxylate (DMF), 2,3-butanediol, and a variety of comonomers viz. glycerol, pentaerythritol or trimethylolpropane are prepared using a solvent-free, bulk polycondensation technique. Extensive molecular and thermal characterization was performed to elucidate the properties of these materials. The materials showed suitable properties for solvent-borne coating applications in terms of their molecular weight, functionality and thermal characteristics, and coatings were prepared using the trimer of hexamethylene diisocyanate as a cross-linker. The resulting coatings, having thicknesses between 30 and 55 lm, were hard but rather brittle. All the coatings have good solvent resistance, pointing to sufficient network formation. It is clear that the presented DMF-based polyesters show promise as bio-based coating resins.