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Gdańsk University of Technology

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Publications from the year 2009

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  • A double-talk detector using audio watermarking
    • Grzegorz Szwoch
    • Andrzej Czyżewski
    • Andrzej Ciarkowski
    2009 JOURNAL OF THE AUDIO ENGINEERING SOCIETY

    a novel approach to double-talk detection in the acoustic echo canceler is proposed. a hidden signature is embedded into the arriving signal, using the echo-hiding method. next detection of the presence of this signature in the microphone signal is performed. the results of the signature detection may be used by the acoustic echo canceler to stop or restart the adaptation process.

  • A fast technique for diplexer design
    • Łukasz Balewski
    • Adam Lamęcki
    • Michał Mrozowski
    2009

    w artykule zaprezentowano nową metodę projektowanie mikrofalowych diplekserów. metoda bazuje na dokładnej syntezie filtrów kanałowych wykorzystującej modele zastępcze współczynników sprzężeń w celu uzyskania wstępnych wartości wymiarów układu. następnie dokonywana jest pełnofalowa optymalizacja filtrów kanałowych. ostateczne strojenie numeryczne jest ograniczone do tylko jednego elementu.

  • A FPTAS for minimizing total completion time in a single machine time-dependent scheduling problem
    • Krzysztof Ocetkiewicz
    2009 EUROPEAN JOURNAL OF OPERATIONAL RESEARCH

    In this paper a single machine time-dependent scheduling problem with total completion time criterion is considered. There are given n jobs J1,…,Jn and the processing time pi of the ith job is given by pi=a+bisi, where si is the starting time of the ith job (i=1,…,n),bi is its deterioration rate and a is the common base processing time. If all jobs have deterioration rates different and not smaller than a certain constant u>0, then for each >0 a solution with the value of the goal function that is at most 1+ times greater than the optimal one can be found. Consequently, the problem cannot be NP-hard in the strong sense.

  • A framework for detection of selfishness in multihop mobile ad hoc networks
    • Jerzy Konorski
    • Rafał Orlikowski
    2009 Full text Journal of Telecommunications and Information Technology

    The paper discusses the need for a fully-distributed selfishness detection mechanism dedicated for multihop wireless ad hoc networks which nodes may exhibit selfish forwarding behaviour. The main contribution of this paper is an introduction to a novel approach for detecting and coping with the selfish nodes. Paper describes a new framework based on Dempster-Shafer Theory called Dempster-Shafer Theory-based Selfishness Detection Framework (DST-SDF) with some mathematical back-ground and simulation analysis.

  • A graph coloring approach to scheduling of multiprocessor tasks on dedicated machines with availability constraints
    • Krzysztof Giaro
    • Marek Kubale
    • Paweł Obszarski
    2009 Full text DISCRETE APPLIED MATHEMATICS

    We address a generalization of the classical 1- and 2-processor unit execution time scheduling problem on dedicated machines. In our chromatic model of scheduling machines have non-simultaneous availability times and tasks have arbitrary release times and due dates. Also, the versatility of our approach makes it possible to generalize all known classical criteria of optimality. Under these stipulations we show that the problem of optimal scheduling of sparse tree-like instances can be solved in polynomial time. However, if we admit dense instances then the problem becomes NP-hard, even if there are only two machines.

  • A JEE-based modelling and execution environment for workflow applications with just-in-time service selection
    • Paweł Czarnul
    2009

    Artykuł prezentuje model scenariusza z dynamicznym wyborem usług do wykonania zadań scenariusza. Adekwatność rozwiązania została zaprezentowana dla zastosowań naukowych i biznesowych w warunkach kiedy dostępność usług się zmienia i usługi powinny być wybierane w trakcie działania scenariusza a nie przed jego rozpoczęciem. Pokazano, że dla scenariusza naukowego z powtarzalnymi symulacjami, algorytm dobiera usługi, aby zminimalizować czas wykonania. Dla scenariusza biznesowego z integracją i dystrybucją towarów, algorytm dobiera usługi minimalizując iloczyn czasu wykonania i sumarycznego kosztu usług. Symulacje przeprowadzono w rzeczywistym środowisku zaimplementowanym przez autora i wdrożonym w systemie BeesyCluster. Zaprezentowano szczegóły implementacyjne oraz narzut rozwiązania.

  • A method of fault diagnosis of analog parts of electronic embedded systems with tolerances
    • Zbigniew Czaja
    2009 Full text MEASUREMENT

    Przedstawiono nową metodę detekcji i lokalizacji uszkodzeń w częściach analogowych z tolerancjami elementów nieuszkodzonych mieszanych sygnałowo elektronicznych systemów wbudowanych sterowanych mikrokontrolerami. Metoda składa się z trzech etapów. W pierwszym etapie tworzony jest słownik uszkodzeń przez aproksymację rodziny pasów lokalizacyjnych. W etapie pomiarowym wewnętrzny licznik mikrokontrolera mierzy czasy trwania impulsów na wyjściach analogowych komparatorów, z których każdy ma inne napięcie progowe. Wejścia tych komparatorów są podłączone do wyjścia badanego układu analogowego pobudzanego impulsem prostokątnym. W ostatnim etapie mikrokontroler dokonuje detekcji i lokalizacji pojedynczych uszkodzeń parametrycznych.

  • A method of the UMTS-FDD network design based on universal load characteristics
    • Sławomir Gajewski
    2009

    In the paper an original method of the UMTS radio network design was presented. The method is based on simple way of capacity-coverage trade-off estimation for WCDMA/FDD radio interface. This trade-off is estimated by using universal load characteristics and normalized coverage characteristics. The characteristics are useful for any propagation environment as well as for any service performance requirements. The practical applications of these characteristics on radio network planning and maintenance were described.

  • A multistage turbine for a micro power plant
    • Krzysztof Kosowski
    • Marian Piwowarski
    • Wojciech Włodarski
    • Robert Stępień
    2009

    This paper presents results of a design analysis of a multi-stage turbine for the cogeneration micro-power plant working in accordance with Organic Rankine Cycle (ORC). The heat power of the plant is assumed equal to 20 kW and the corresponding available electric output is estimated to be of about 3 kW. Different variants of the radial and axial-flow turbines have been considered, while the detailed results of the calculations of the flow part of 5-stage turbine with partial admission are shown in the paper. The proposed solution has a relatively high efficiency and a rotor speed of about 8000 rpm which is a low value compared with other considered variants.

  • A New Approach For High Speed Data Transmission Monitoring
    • Marek Zmuda
    • Stanisław Szczepański
    2009

    W artykule przedstawiono nowatorski sposób monitorowania szybkiej transmisji danych. Technika została zaprezentowana dla przypadku transmisji różnicowej na płycie drukowanej. Cechą szczególną rozwiązania jest możliwość pomiaru jakości transmisji w linii bez konieczności montowania dedykowanych złącz pomiarowych, które mogłyby degradować transmisję.

  • A new approach to active noise and vibration control - [Part I: the known frequency case]
    • Maciej Niedźwiecki
    • Michał Meller
    2009 Full text

    This paper presents a new approach to rejection of complex-valued sinusoidal disturbances acting at the output of a discrete-time stable linear plant with unknown dynamics. It is assumed that the frequency of the sinusoidal disturbance is known, and that the output signal is contaminated with wideband measurement noise. The disturbance rejection control rule is first derived and analyzed for a nominal plant model, different from the true model. Then a special adaptation mechanism is added, which is capable of compensating modeling biases (errors in both magnitude and phase) so that, under Gaussian assumptions, the closed-loop system can converge in mean to the optimal solution.

  • A new approach to active noise and vibration control - [Part II: unknown frequency case]
    • Maciej Niedźwiecki
    • Michał Meller
    2009 Full text

    This paper presents a new approach to rejection of complex-valued sinusoidal disturbances acting at the output of a discrete-time stable linear plant with unknown and possibly timevarying dynamics. It is assumed that both the instantaneous frequency of the sinusoidal disturbance and its amplitude may be slowly varying with time and that the output signal is contaminated with wideband measurement noise. It is not assumed that a reference signal, correlated with the disturbance, is available. The proposed disturbance rejection algorithm is an extension of the algorithm derived for the constant-known-frequency case, described in Part I of this paper.

  • A new approach to provide the differentiated levels of network survivability under a double node failure
    • Jacek Rak
    • Wojciech Molisz
    2009

    W artykule zaproponowano klasową metodę ochrony strumieni ruchu w sieciach WDM zapewniającą szybkie odtwarzanie połączeń w sytuacji jednoczesnej awarii jej dwóch elementów. Szczególny nacisk położono na zagadnienie zapewnienia zróżnicowanych poziomów przeżywalności w celu ich lepszego dopasowania do zróżnicowanych wymagań użytkowników. Pokazano, że w celu zapenienia ochrony przed awarią dwóch elementów, wymagania dotyczące przepustowości łączy są do 40% większe w porównaniu z przypadkiem ochrony przed awaria jednego elementu sieci. Czas odtwarzania uszkodzonych połączeń również ulega zwiększeniu. Jednakże możliwe jest ograniczenie czasu odtwarzania połączeń poprzez redukcję wielkości obszarów ochrony.

  • A new B-D-galactosidase with a low temperature optimum isolated from the Antarctic Arthrobacter sp. 20B: gene cloning, purification and characterization.
    • Aneta Białkowska
    • Hubert Cieśliński
    • Karolina Nowakowska
    • Józef Kur
    • Marianna Turkiewicz
    2009 ARCHIVES OF MICROBIOLOGY

    A psychrotrophic bacterium producing a coldadaptedB-galactosidase upon growth at low temperatureswas classiWed as Arthrobacter sp. 20B. A genomic DNAlibrary of strain 20B introduced into Escherichia coliTOP10F' and screening on X-Gal (5-bromo-4-chloro-3-indolyl-B-D-galactopyranoside)-containing agar plates ledto the isolation of B-galactosidase gene. The B-galactosidasegene (bgaS) encoding a protein of 1,053 amino acids,with a calculated molecular mass of 113,695 kDa. Analysisof the amino acid sequence of BgaS protein, deduced fromthe bgaS ORF, suggested that it is a member of the glycosylhydrolase family 2. A native cold-adapted B-galactosidasewas puriWed to homogeneity and characterized. It is ahomotetrameric enzyme, each subunit being approximately116 kDa polypeptide as deduced from native and SDS-PAGE, respectively. The B-galactosidase was optimallyactive at pH 6.0-8.0 and 25°C. P-nitrophenyl-B-D-galactopyranoside(PNPG) is its preferred substrate (three timeshigher activity than for ONPG-o-nitrophenyl-B-D-galactopyranoside).The Arthrobacter sp. 20B Beta-galactosidase isactivated by thiol compounds (53% rise in activity in thepresence of 10 mM 2-mercaptoethanol), some metal ions(activity increased by 50% for Na+, K+ and by 11% forMn2+) and inactivated by pCMB (4-chloro-mercuribenzoicacid) and heavy metal ions (Pb2+, Zn2+, Cu2+).

  • A new cold-adapted beta-D-galactosidase from the Antarctic Arthrobacter sp. 32c - gene cloning, overexpression, purification and properties
    • Piotr Hildebrandt
    • Marta Wanarska
    • Józef Kur
    2009 Full text BMC MICROBIOLOGY

    The development of a new cold-active β-D-galactosidases and microorganisms that efficiently ferment lactose is of high biotechnological interest, particularly for lactose removal in milk and dairy products at low temperatures and for cheese whey bioremediation processes with simultaneous bio-ethanol production. In this article, we present a new β-D-galactosidase as a candidate to be applied in the above mentioned biotechnological processes. The gene encoding this β-D-galactosidase has been isolated from the genomic DNA library of Antarctic bacterium Arthrobacter sp. 32c, sequenced, cloned, expressed in Escherichia coli and Pichia pastoris, purified and characterized. 27 mg of β-Dgalactosidase was purified from 1 L of culture with the use of an intracellular E. coli expression system. The protein was also produced extracellularly by P. pastoris in high amounts giving approximately 137 mg and 97 mg of purified enzyme from 1 L of P. pastoris culture for the AOX1 and a constitutive system, respectively. The enzyme was purified to electrophoretic homogeneity by using either one step- or a fast two step- procedure including protein precipitation and affinity chromatography. The enzyme was found to be active as a homotrimeric protein consisting of 695 amino acid residues in each monomer. Although, the maximum activity of the enzyme was determined at pH 6.5 and 50°C, 60% of the maximum activity of the enzyme was determined at 25°C and 15% of the maximum activity was detected at 0°C. The properties of Arthrobacter sp. 32c β-D-galactosidase suggest that this enzyme could be useful for low-cost, industrial conversion of lactose into galactose and glucose in milk products and could be an interesting alternative for the production of ethanol from lactose-based feedstock.

  • A new locality of Omphalina umbellifera (L.: Fr.) Quel. in Gdańsk Pomerania = Porost pępówka pofałdowana Omphalina umbellifera (L.: Fr.) Quel. - nowe stanowiska na Pomorzu Gdańskim
    • Marcin Wilga
    2009 CHROŃMY PRZYRODĘ OJCZYSTĄ

    W pracy przedstawiono nowe stanowiska porostu pępówki pofałdowanej (Omphalina umbellifera) znajdujące się na obszarze torfowiska Księże Błoto w pobliżu osiedla Nowy Świat na Pomorzu Gdańskim

  • A new method for determination of flow boiling heat transfer coefficient in conventional diameter channels and minichannels
    • Dariusz Mikielewicz
    2009 HEAT TRANSFER ENGINEERING

    W pracy przedstawiono rozważania związane z modelowaniem wrzenia w przepływie w kanałach o średnicach konwencjonalnych, małych i minikanałach. Przedstawiono przegląd podejść do modelowania wymiany ciepła i w tym świetle przedstawiono oryginalne podejście autora. W przeciwieństwie do innych podejść metoda autora ma zastosowanie zarówno do kanałów o średnicach konwencjonalnych i minikanałach. Przedstawiono zadowalające porównania z danymi eksperymentalnymi.

  • A new methodological approach to the noise threat evaluation based on the selected physiological properties of the human hearing system
    • Andrzej Czyżewski
    • Bożena Kostek
    • Józef Kotus
    2009

    A new way of assessment of noise-induced harmful effects on human hearing system is presented in the paper. The method takes into consideration properties of the selected physiological human hearing system. On the basis of the hearing examinations and noise measurements results and psychoacoustical noise dosimeter performance the new indicators of the noise harmfulness were proposed. The evaluation of the proposed indicators were conducted on the basis of hearing examination in the real noise exposure situations and also on the basis of the simulation results using standard test signals (such as: white, pink and brown noise). The performed analysis and obtained results confirmed the practical usefulness and correctness of the proposed indicators.

  • A new optimal algorithm for a time-dependent scheduling problem
    • Marek Kubale
    • Krzysztof Ocetkiewicz
    2009 CONTROL AND CYBERNETICS

    In this article a single machine time-dependent scheduling problem with total completion time criterion is considered. There are n given jobs j_1, ..., j_n and the processing time pi of the i-th job is given by p_i = 1 + b_is_i, where si is the starting time of the i-th job, i = 1, ..., n. If all jobs have different and non-zero deterioration rates and bi > bj => bi >= (b_min+1)/(b_min) b_j + 1/b_min, where b_min = min{b_i}, then an optimal schedule can be found in O(n log n) time. Moreover, the conducted computational experiments show that the presented algorithm performs very well even on data not meeting the given constraints.

  • A note on the strength and minimum color sum of bipartite graphs
    • Adrian Kosowski
    2009 Full text DISCRETE APPLIED MATHEMATICS

    Siłą grafu G nazywamy najmniejszą liczbę całkowitą s, taką że istniej pokolorowanie grafu G, o minimalnej sumie przy użyciu kolorów {1,...,s}. W pracy pokazano, że w grafach dwudzielnych stopnia D zachodzi oszacowanie s <= ceil(D/2) + 1. Z obserwacji tej wynika algorytm wielomianowy do obliczania siły i sumy chromatycznej w grafach dwudzielnych stopnia co najwyżej 4.