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Gdańsk University of Technology

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Publications from the year 2018

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  • Utlenianie anodowe biostopu Ti6Al4V w aspekcie jego zastosowań w implantacji
    • Magda Chorzelska
    • Magdalena Jażdżewska
    2018 INŻYNIER I FIZYK MEDYCZNY

    Stop tytanu z aluminium i wanadem jest jednym z najczęściej używanych stopów tytanu w implantologii. Ti6Al4V charakteryzuje się dobrymi właściwościami i jest względnie tani. Na stopie wytworzono warstwy metodą anodowania, przy zastosowaniu trzech różnych elektrolitów i różnych parametrów procesu. Na wszystkich próbkach otrzymano nanorurki.

  • UV-Vis-Induced Degradation of Phenol over Magnetic Photocatalysts Modified with Pt, Pd, Cu and Au Nanoparticles
    • Izabela Wysocka
    • E. Kowalska
    • Konrad Trzciński
    • Marcin Stanisław Łapiński
    • Grzegorz Nowaczyk
    • Anna Zielińska-Jurek
    2018 Full text Nanomaterials

    The combination of TiO2 photocatalyst and magnetic oxide nanoparticles enhances the separation and recoverable properties of nanosized TiO2 photocatalyst. Metal-modified (Me = Pd, Au, Pt, Cu) TiO2/SiO2@Fe3O4 nanocomposites were prepared by an ultrasonic-assisted sol-gel method. All prepared samples were characterized by X-ray powder diffraction (XRD) analysis, Brunauer-Emmett-Teller (BET) method, X-ray photoelectron spectroscopy (XPS), scanning transmission electron microscopy (STEM), Mott-Schottky analysis and photoluminescence spectroscopy (PL). Phenol oxidation pathways of magnetic photocatalysts modified with Pt, Pd, Cu and Au nanoparticles proceeded by generation of reactive oxygen species, which oxidized phenol to benzoquinone, hydroquinone and catechol. Benzoquinone and maleic acid were products, which were determined in the hydroquinone oxidation pathway. The highest mineralization rate was observed for Pd-TiO2/SiO2@Fe3O4 and Cu-TiO2/SiO2@Fe3O4 photocatalysts, which produced the highest concentration of catechol during photocatalytic reaction. For Pt-TiO2/SiO2@Fe3O4 nanocomposite, a lack of catechol after 60 min of irradiation resulted in low mineralization rate (CO2 formation). It is proposed that the enhanced photocatalytic activity of palladium and copper-modified photocatalysts is related to an increase in the amount of adsorption sites and efficient charge carrier separation, whereas the keto-enol tautomeric equilibrium retards the rate of phenol photomineralization on Au-TiO2/SiO2@Fe3O4. The magnetization hysteresis loop indicated that the obtained hybrid photocatalyst showed magnetic properties and therefore could be easily separated after treatment process

  • Uwarunkowania diagnostyczne sterowania procesem eksploatacji okrętowych silników głównych
    • Jacek Rudnicki
    2018 Full text Journal of Polish CIMEEAC

    Ze względu na losowość czynników wymuszających podczas użytkowania urządzeń okrętowych w praktyce eksploatacyjnej okrętowych układów energetycznych wdrażanych jest coraz więcej elementów strategii eksploatacji wg stanu technicznego (ang. Condition Based Maintenance). W referacie przedstawiono wybrane problemy dotyczące diagnostyki jako niezbędnego ogniwa w ciągu czynności związanych z podejmowaniem racjonalnych, podyktowanych aktualnym stanem technicznym, decyzji eksploatacyjnych. W tym aspekcie zwrócono uwagę na konieczność odpowiedniego zorganizowania badań diagnostycznych oraz sposobu gromadzenia ich wyników pod kątem zastosowania w przyjętym modelu decyzyjnym. Ilustracją przedstawionych rozważań jest zaproponowany model procesów: zmian stanu technicznego i eksploatacyjnego silnika okrętowego opracowany z wykorzystaniem teorii procesów semimarkowskich. Uzyskane na podstawie tych modeli wartości odpowiednich wskaźników mogą zostać użyte w procesie decyzyjnym np. podczas wzmiankowanym w referacie opracowaniu drzewa decyzyjnego.

  • UWARUNKOWANIA DOTYCZĄCE WDRAŻANIA ZAKŁADOWEJ KONTROLI PRODUKCJI W SEKTORZE MŚP
    • Piotr Grudowski
    • Magdalena Kałużna
    2018

    Zakładowa Kontrola Produkcji (ZKP) to branżowy system jakości, dedykowany producentom wyrobów budowlanych. System ten został ustanowiony 29 lat temu w Unii Europejskiej. W polskim systemie prawnym jest obecny od 2004 roku, przy czym w zgodzie z przepisami UE podlega zmianom i jest nowelizowany w ramach ustawy. Celem autorów przyjętym w niniejszym opracowaniu jest identyfikacja uwarunkowań wdrażania ZKP oraz newralgicznych obszarów ZKP w sektorze MŚP. Praktyczne rozwiązania dotyczące zastosowania wymagań ZKP wymagają w tej grupie przedsiębiorstw dedykowanego podejścia a niezgodności z tym związane mogą spowodować szczególnie dotkliwe konsekwencje dla mniejszych producentów.

  • UWARUNKOWANIA I SKUTKI ŻYWIOŁOWEJ SUBURBANIZACJI W POLSCE. CZY OPANOWANIE JEJ JEST MOŻLIWE?
    • Jacek Sołtys
    2018 Full text Studia Komitetu Przestrzennego Zagospodarowania Kraju PAN

    Artykuł dotyczy procesu żywiołowej suburbanizcji (urban sprawl) w Polsce. Jego celami są: (1) analiza powiązań między negatywnymi skutkami tego procesu, (2) prezentacja negatywnych skutków dla transportu i zużycia energii oraz ładu przestrzennego, (3) analiza sposobów przeciwdziałania negatywnym procesom, w tym uwarunkowań (w szczególności ograniczeń) stosowania tych sposobów i ich skuteczności. Jako metody zastosowano: obserwację, analizę literatury i analizę logiczną. Siły napędowe zmierzają w kierunku dalszej suburbanizacji, której zatrzymanie uznano za niemożliwe. Ukierunkowanie procesów w kierunku uwzględniania w większym stopniu ładu przestrzennego jest bardzo trudne. Istnieją do tego odpowiednie rozwiązania, w tym prawne, ale istnieją też bariery w ich stosowaniu, takie jak: brak świadomości i motywacji władz lokalnych oraz warunki polityczne, które zniechęcają do bardziej restrykcyjnych regulacji.

  • Uwarunkowania propagacyjne w ultraszerokopasmowej komunikacji typu off-body w środowisku trudnym
    • Krzysztof Cwalina
    • Sławomir Ambroziak
    • Piotr Rajchowski
    • Luis M. Correia
    2018 Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

    W niniejszym referacie przedstawiono analizę uwarunkowań propagacyjnych w ultraszerokopasmowej komunikacji typu off-body w środowisku trudnym pod względem propagacji fal radiowych. Badania przeprowadzono z użyciem mobilnego stanowiska pomiarowego zawierającego węzły sieci WBAN wyposażone w ultraszerokopasmowe moduły radiowe DWM1000 firmy DecaWave. Uzyskane wartości tłumienia systemowego przeanalizowano dla dwóch dynamicznych scenariuszy pomiarowych oraz trzech miejsc montażu anten na ciele człowieka zgodnie z występującymi warunkami LOS oraz NLOS.

  • Uwarunkowania rozwoju e-administracji w Polsce
    • Katarzyna Kubiszewska
    • Aleksandra Makowska
    • Jędrzej Wieczorkowski
    2018

    Celem opracowania są w szczególności: - Ocena poziomu rozwoju e-administracji w Polsce oraz innych, w szczególności europejskich, krajach w okresie transformacji. - Identyfikacja i ocena wpływu czynników determinujących poziom rozwoju e-administracji. - Wskazanie korzyści wynikających ze stosowania rozwiązań e-administracji oraz barier w ich wdrażaniu. - Identyfikacja problemów i niespójności w planowaniu i realizacji e-usług publicznych. - Określenie metod wykorzystania narzędzi marketingowych najbardziej efektywnych w procesie budowania e-administracji. - Ocena przygotowania służb IT w urzędach do prowadzenia usług on-line.

  • Validated HPTLC method for determination of ledol and alloaromadendrene in the essential oil fractions of Rhododendron tomentosum plants and in vitro cultures and bioautography for their activity screening
    • Anna Jesionek
    • Loretta Poblocka-Olech
    • Bożena Zabiegała
    • Adam Bucinski
    • Miroslawa Krauze-Baranowska
    • Maria Luczkiewicz
    2018 JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES

    Rhododendron tomentosum (Ledum palustre) is a bog shrub used in traditional medicine for treatment of respiratory and rheumatic diseases. Due to the large variability of the chemical composition of its essential oil, depending on the habitat, the in vitro cultures were established as the alternative source of the volatile fraction. There is a need to monitor a quality of the field grown as well as in vitro plant material, especially if potentially toxic aromadendrane derivatives are concerned. In this study the HPTLC method was developed and validated for quantification of ledol and alloaromadendrene in R. tomentosum essential oils obtained from the plants collected in various locations as well as in vitro cultures. For qualitative analysis, chromatograms were developed on HPTLC Si 60 plates at distance of 50 mm without preconditioning using hexane: ethyl acetate (9:1) and visualized with p-anisaldehyde reagent. For quantitative analysis, chromatograms were developed on HPTLC Si 60 plates at distance of 40 mm with 20 min preconditioning using hexane: ethyl acetate (9:1), visualized with vanillin/phosphoric acid reagent and subjected to densitometric detection (560 nm). The content of ledol and alloaromadendrene in different samples was determined using the validated HPTLC method (12–280 mg and 2–60 mg 100 g−1 dried plant material, respectively) and was compared with GC/MS results. The bioautographic antioxidant HPTLC assays in DPPH and in riboflavin-light-NBT systems as well as the test for xanthine oxidase inhibition were employed for screening of the biological activity of the R. tomentosum essential oils.

  • Variability of relationship between cities and nature in landscape architecture= Zmienność relacji miedzy miastem a naturą na przykładzie architektury krajobrazu miast
    • Maura Zaworska
    2018

    Interpreting and creating the relations between nature and city are the process of learning which is a subject of permanent conceptualization. It is characterized by the culutrality due to human nature and own ability to perceive oneself in the context of the relationship between own environmental and cultural nature. The way of interpreting the nature and providing it with different features affected significantly the development of the image of the cities. Over the centuries, human treated own natural part of the human being as something external, something that needs to be managed and disciplined. The change of mind and perceiving one’s own as a being that is a part of nature and which nature/core is to create the culture, recently led to the reconceptualiation of the relationship between nature and city.

  • VARIABLE KINEMATICS OF HONING PROCESS – INFLUENCE ON MACHINED WORKPIECE
    • Piotr Sender
    2018

    Surface quality of holes plays an important role in machine manufacturing industry especially in the production of car engines and hydraulic cylinders. Investigations of honing process were carried out by 6 years on horizontal CNC Sunnen’s honing machine HTH 4000S, on vertical conventional honing machine WMW’s SZS 200 and on CNC milling machine of Haas VF 3SS with equipment of Honingtec for honing. Measurements of cylindricity of holes was done on CNC coordinate measuring machine Zeiss Accura, measuring of roughness was done using surface roughness measurement instrument of Mitutoyo SJ-210. The influence of variable kinematics of honing process has a positive impact for many aspects of performing of efficient and accurate honing process.

  • Variable-fidelity shape optimization of dual-rotor wind turbines
    • Thelen Andrew
    • Leifsson Leifur
    • Sharma Anupam
    • Sławomir Kozieł
    2018 ENGINEERING COMPUTATIONS

    Purpose Dual-rotor wind turbines (DRWTs) are a novel type of wind turbines that can capture more power than their single-rotor counterparts. Because their surrounding flow fields are complex, evaluating a DRWT design requires accurate predictive simulations, which incur high computational costs. Currently, there does not exist a design optimization framework for DRWTs. Since the design optimization of DRWTs requires numerous model evaluations, the purpose of this paper is to identify computationally efficient design approaches. Design/methodology/approach Several algorithms are compared for the design optimization of DRWTs. The algorithms vary widely in approaches and include a direct derivative-free method, as well as three surrogate-based optimization methods, two approximation-based approaches and one variable-fidelity approach with coarse discretization low-fidelity models. Findings The proposed variable-fidelity method required significantly lower computational cost than the derivative-free and approximation-based methods. Large computational savings come from using the time-consuming high-fidelity simulations sparingly and performing the majority of the design space search using the fast variable-fidelity models. Originality/value Due the complex simulations and the large number of designable parameters, the design of DRWTs require the use of numerical optimization algorithms. This work presents a novel and efficient design optimization framework for DRWTs using computationally intensive simulations and variable-fidelity optimization techniques.

  • Vegetable derived-oil facilitating carbon black migration from waste tire rubbers and its reinforcement effect
    • Pan Song
    • Chaoying Wan
    • Yanling Xie
    • Krzysztof Formela
    • Shifeng Wang
    2018 WASTE MANAGEMENT

    Three dimensional chemically cross-linked polymer networks present a great challenge for recycling and reutilization of waste tire rubber. In this work, the covalently cross-linked networks of ground tire rubber (GTR) were degraded heterogeneously under 150 °C due to the synergistic effects of the soybean oil and controlled oxidation. The degradation mechanism was discussed using Horikx theory and Fourier transformation infrared spectroscopy (FTIR). The results showed that the structural evolution of sol and gel parts, which indicated that the sols consisted of degraded GTR chains with low molecular weight, while the gels were mainly composed of bound rubber coated carbon black, which are separated from the cross-linked network of GTR in a high degradation degree. The degraded GTR compound demonstrated an excellent reinforcing effect on solution styrene-butadiene rubber (SSBR), due to the presence of core-shell structured carbon black. This work provide an efficient and economic approach to degrade GTR and transform it into useful products.

  • Vehicle detector training with labels derived from background subtraction algorithms in video surveillance
    • Sebastian Cygert
    • Andrzej Czyżewski
    2018

    Vehicle detection in video from a miniature station- ary closed-circuit television (CCTV) camera is discussed in the paper. The camera provides one of components of the intelligent road sign developed in the project concerning the traffic control with the use of autonomous devices being developed. Modern Convolutional Neural Network (CNN) based detectors need big data input, usually demanding their manual labeling. In the presented research approach the weakly-supervised learning paradigm is used for the training of a CNN based detector em- ploying labels obtained automatically through an application of video background subtraction algorithm. The proposed method is evaluated on GRAM-RTM dataset and a CNN fine-tuned with labels from the background subtraction algorithm. Even though obtained representation in the form of labels may include many false positives and negatives, a reliable vehicle detector was trained employing them. The results are presented showing that such a method can be applied to traffic surveillance systems.

  • Verification of baffle factor for straight pipe flow
    • Wojciech Artichowicz
    • Aneta Łuczkiewicz
    • Jerzy Sawicki
    2018 Full text Archives of Hydro-Engineering and Environmental Mechanics

    During the water disinfection devices designing, it is often assumed that the baffle factor for a straight pipe reactors is equal to one. It would be possible only for the plug flow, which is a simplified model of the flow and does not appear in real situations. The paper contains an equation which enables calculation of the real value of the baffle factor for the pipe flow.

  • Verification of selected calculation methods regarding shear strength in beams without web reinforcement
    • Marta Hirsz
    • Krystyna Nagrodzka-Godycka
    2018 Full text MATEC Web of Conferences

    The purpose of the article was to compare selected calculation methods regarding shear strength in reinforced concrete beams without web reinforcement. Several calculation methods were tested. This included codes: PN-EN 1992-1-1:2008, ACI 318-14 and fib Model Code for Concrete Structures 2010. The analysis also consists of authorial methods published in technical literature. Calculations of shear strengths were made based on experimental works found in literature. The shear strength ratios Vtest/Vcalc were chosen to be the yardstick of comparison, where Vtest is the experimental shear strength and Vcalc is the calculated shear strength.. A wide range of variables including shear span/depth ratio, compressive strength of concrete, longitudinal steel percentage helped to verify the applicability of calculation methods. Although most of authorial techniques proved to be unstable, they succeeded to show that codes' formulas for shear strength may still be improved. The presented article is a part of Authors' long term research in the matter and a new chapter of their study now concerning beams without web reinforcement.

  • Verification of the new viscoelastic method of thermal stress calculation in asphalt layers of pavements
    • Józef Judycki
    2018 International Journal of Pavement Engineering

    The new viscoelastic method of thermal stress calculations in asphalt layers has been developed and published recently by the author. This paper presents verification of this method. The verification is based on the comparison of the results of calculations with results of testing of thermal stresses in Thermal Stress Restrained Specimen Test. The calculations of thermal stresses according to the new method were based on rheological parameters of the Burgers model. The parameters were measured in laboratory at different low temperatures, at long time creep under constant loading. Five asphalt mixes were tested. Three of them were high modulus asphalt concretes and two conventional asphalt concretes. Specimens were prepared in exactly the same way both for rheological creep tests and for the Thermal Stress Restrained Specimen Test. The results of measured thermal stresses were compared with thermal stresses calculated from the new viscoelastic method developed by the author and in most cases a good agreement was found. For comparison, the measured stresses were compared with results of calculations according to the existing methods. The viscoelastic Monismith method failed in prediction of thermal stresses. The prediction from the quasi-elastic Hills and Brien method was underestimated, but better than from the Monismith method and worse than from the new viscoelastic method. The reasons of discrepancies were discussed.

  • Vernacular and neovernacular architecture without a user. Wooden catholic churches in the vicinity of brody in Ukraine.
    • Jakub Szczepański
    • Agnieszka Szuta
    2018

    One of the basic theoretical postulates for the protection of monuments is to preserve them in the place of their creation. However, such action is not always possible to implement. The great historical processes of the 20th century led to significant national, political, religious and cultural changes in the border areas between Poland and Ukraine. As a result of those changes, a large number of wooden churches have lost their users. These buildings indicate the development of the skills of using wood as the basic building material through many centuries in the region of today’s borderland of Poland and Ukraine. These above-mentioned churches were built from the Middle Ages up to the 20th century. They were constructed by both rural carpenters and high-class architects. This is a great example of the cultural diversity of the regional heritage. Nevertheless, existence of many of these objects are at risk now. The problem concerns especially the Greek Catholic churches and Orthodox churches in south-eastern Poland. In this region, up to the 1940s Greek Catholics and followers of the Orthodox Church constituted a significant group of citizens but nowadays, they are only a small minority. The situation is similar in western Ukraine, where are only a few Roman Catholic. The article presents three churches which have been deprived of their primary users. They have been located in western Ukraine, near the city of Brody in the villages of: Jazłowczyk, Stanisławczyk and Ruda Brodzka. One of these churches has been saved, as a result of the transfer of the original church to the open-air museum. Unfortunately, it is not possible to preserve the other two buildings.

  • Versatility of putative aromatic aminotransferases from Candida albicans.
    • Kamila Rząd
    • Sławomir Milewski
    • Iwona Gabriel
    2018 Full text FUNGAL GENETICS AND BIOLOGY

    Amino acids constitute the key sources of nitrogen for growth of Candida albicans. In order to survive inside the host in different and rapidly changing environments, this fungus must be able to adapt via its expression of genes for amino acid metabolism. We analysed the ARO8, ARO9, YER152C, and BNA3 genes with regards to their role in the nutritional flexibility of C. albicans. CaAro8p is undoubtedly the most versatile enzyme among the aminotransferases investigated. It is involved in the catabolism of histidine, lysine, and aromatic amino acids as well as in L-Lys, Phe and Tyr biosynthesis. CaAro9p participates in the catabolism of aromatic amino acids and lysine at high concentrations of these compounds, with no biosynthetic role. Conversely, the CaYer152Cp catalytic potential for aromatic amino acid catabolism observed in vitro appears to be of little importance in vivo. Neither biosynthetic nor catabolic roles of CaBan3p were observed for any proteinogenic amino acid. Finally, none of the analysed aminotransferases was solely responsible for the catabolism of a single particular amino acid or its biosynthesis.

  • Vertical motions damping model test of a lifeboat lowered onto a flat sea surface
    • Aleksander Kniat
    • Paweł Dymarski
    2018 Full text Polish Maritime Research

    The article presents the experiment’s results of the lifeboat model lowered with an initial speed and then released to fall onto a flat water surface. The purpose of the research is to determine the trajectory of the vertical boat motion and describe it with a mathematical model. This is closely related to determining the damping factor since the vertical motion is damped and the lifeboat gets balanced and stops moving after some time. The procedure of selecting parameters in the mathematical model to adjust to the results of the experiment was described in details. The summary describes the imperfections of the presented damping model and their probable causes.

  • Vertical Temperature Stratification of the Gulf of Gdansk Water
    • Grażyna Grelowska
    • Eugeniusz Kozaczka
    • Dominika Witos-Okrasińska
    2018

    The Baltic Sea is characterized by variable hydroacoustic conditions, which depend on hydrological conditions throughout the year. The temperature of the water is the factor that has the greatest impact on the changes in the speed of the sound in this basin. Even at a small depth, we can observe a large temperature gradient affecting the accuracy of the conducted research using hydroacoustic devices. A characteristic feature of the Baltic waters is their layering. In the Baltic Sea, we distinguish three main layers of water: surface, whose temperature is closely related to air temperature and varies within 1-22 degrees during the year, an intermediate characterized by the occurrence of a seasonal thermocline and deep sea temperature, which fluctuates within small limits from 4-6 degrees. There are many factors influencing water temperature changes, among others: heat exchange between water and atmosphere, floods of water with higher salinity from the North Sea, strong winds occurring in the autumn-winter period, an upwelling phenomenon, inflow of fresh waters from rivers. The paper presents the results of research carried out in the Gulf of Gdansk and their impact on the acoustic conditions of the Baltic waters.