2018 - Publications Repository - Gdańsk University of Technology

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Publications from the year 2018

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ENERGY ANALYSIS OF PROPULSION SHAFT FATIGUE PROCESS IN ROTATING MECHANICAL SYSTEM PART I TESTING SIGNIFICANCE OF INFLUENCE OF SHAFT MATERIAL FATIGUE EXCITATION PARAMETERS
- Zbigniew Korczewski
- Konrad Marszałkowski
2018 Full text Polish Maritime Research
The article discusses the problem of mathematical modelling of energy conversion processes in a rotating mechanical system for the purpose of identifying fatigue states of propulsion shafts in this system. A simplified physical model of the analysed system, constructed in an appropriate scale, has made the basis for the experimental research. The research programme took into consideration mechanical fatigue excitation of the model propulsion shaft to find the correlation between the dynamic system load generated by a bending moment and the energy state of a specified shaft segment. A physical model of the analysed process was proposed, for which the plan of static randomised block experiment was worked out. The recorded experimental results were used for statistical analysis of the significance of influence of the quantities exciting the propeller shaft fatigue process and the adequacy of the developed mathematical model describing shaft’s durability. The analysis made use of the F-Snedecor test. The article describes the general concept of the research, the constructed laboratory test rig, and the methodology of statistical inference concerning the significance of influence of input (exciting) parameters of the physical model on the recorded output parameters. The results of the performed statistical tests confirm the absence of the significance of influence of the rotational speed of the propulsion shaft on the selected types of rotating operation of the mechanical system. As a consequence, only one exciting parameter, which is the loading mass, is going to be taken into account in the functional description of fatigue life of the propulsion shaft.
Energy Efficiency Analysis of Railway Turnout Heating With a Simplified Snow Model Using Classical and Contactless Heating Method
- Mateusz Flis
- Mirosław Wołoszyn
2018
Electrical heating of railway turnouts is a considerable technical and economic challenge, hence the need to conduct research for optimisation of a railway turnouts heating system. This paper presents results of a numerical analysis and experimental research on heating systems mounted on rail turnouts in line with the classical method and including a heater thermally insulated from the base of a rail. The numerical calculations of the heating processes were carried out in ANSYS software.
Energy Modeling of Single-Family Houses in the Conceptual Phase
- Maria Helenowska-Peschke
2018
The aim of the article is to identify the potential impact of the latest commercial digital tools for building energy analysis on the everyday architectural practice in Poland in the context of typology and energy optimization of single –family houses. The reason for this survey is that “architect friendly” interfaces simulation results’ visualization and energy analysis tools are not given deserved attention in the architectural education in Poland thus some of the design opportunities for sustainability solutions are lost. The possibilities and limitations of Insight 360 integrated with BIM technology and tailored to needs of architects are discussed based a conceptual house model of curvilinear geometry. Insight 360 enables architects to examine implications of early design decisions on the building energy usage and to identify areas for possible improvements. In the later stages of house design energy simulations serve to demonstrate design compliance with local building codes and ordinances, voluntary green building programs and/or customer requirements.
Engineering Analysis with ANSYS Software Second Edition
- Tadeusz Stolarski
- Nakasone Yuji
- Shigeka Yoshimoto
2018
The best way to learn complex systems is by means of hands-on experience. With an innovative and clear tutorial based approach, this powerful book provides a comprehensive introduction to the fundamental areas of engineering analysis needed on research or commercial engineering projects. With its detailed step-by-step explanations and sample problems, this book will develop the reader's understanding of FEA and their ability to use ANSYS software tools to solve a range of analysis problems.
Enhanced energy conversion as a result of fluid-solid interaction in micro- and nanoscale
- Janusz Badur
- Paweł Ziółkowski
- Sebastian Kornet
- Tomasz Kowalczyk
- Kamil Banaś
- Mateusz Bryk
- Piotr Ziółkowski
- Michał Stajnke
2018 Full text Journal of Theoretical and Applied Mechanics
It is known that nano- and micromechanics require new approaches to right describing of surface-like phenomena which lead to an enhanced energy conversion. In this work, a general form of surface forces that consist of a contribution from both the friction and mobility components has been extended to collect the effects of bulk and surface motion of a fluid. Quite similar impact can be observed for a solid-fluid mixture, where the principle of effective stress for this new type of approach should be considered from the very beginning. The second motivation of our work is to present the multiscale domain of fluid-solid interaction which describes some “emergence effects” for materials with especially high volumetric surface densities.
Enhancement of fiber-optic low-coherence Fabry-Pérot interferometer with ZnO ALD films
- Marzena Hirsch
- Paulina Listewnik
- Małgorzata Szczerska
2018
In this paper investigation of the enhanced fiber-optic low coherence Fabry-Pérot interferometer with zinc oxide (ZnO) film deposited by atomic layer deposition (ALD) was presented. Model of the interferometer, which was constructed of single-mode optical fiber with applied ZnO ALD films, was built. The interferometer was also examined by means of experiment. Measurements were performed for both reflective and transmission modes, using wavelengths of 1300 nm and 1500 nm. The measurements with the air cavity showed the best performance in terms of a visibility of the interference signal can be achieved for small cavity lengths (~ 50μm) in both configurations. Combined with the enhancement of reflectance of the interferometer mirrors due to the ALD film, proposed construction could be successfully applied in refractive index (RI) sensor that can operate with improved visibility of the signal even in 1.3-1.5 RI range as well as with small volume samples, as shown by the modeling
Entangled Histories vs. the Two-State-Vector Formalism - Towards a Better Understanding of Quantum Temporal Correlations
- Marcin Nowakowski
- Eliahu Cohen
- Paweł Horodecki
2018 Full text PHYSICAL REVIEW A
The Two-State-Vector formalism and the Entangled Histories formalism are attempts to betterunderstand quantum correlations in time. Both formalisms share some similarities, but they are notidentical, having subtle differences in their interpretation and manipulation of quantum temporalstructures. However, the main objective of this paper is to prove that, with appropriately definedscalar products, both formalisms can be made isomorphic. We show, for instance, that theytreat operators and states on equal footing leading to the same statistics for all measurements. Inparticular, we discuss the topic of quantum correlations in time and show how they can be generatedand analyzed in a consistent way using these formalisms. Furthermore, we elaborate on a novelbehavior of quantum histories of evolving multipartite systems which do not exhibit global non-local correlations in time but nevertheless can lead to entangled reduced histories characterizingevolution of an arbitrarily chosen sub-system
Entropy Production Associated with Aggregation into Granules in a Subdiffusive Environment
- Piotr Weber
- Piotr Bełdowski
- Martin Bier
- Adam Gadomski
2018 Full text ENTROPY
We study the entropy production that is associated with the growing or shrinking of a small granule in, for instance, a colloidal suspension or in an aggregating polymer chain. A granule will ﬂuctuate in size when the energy of binding is comparable to k_{B}T, which is the “quantum” of Brownian energy. Especially for polymers, the conformational energy landscape is often rough and has been commonly modeled as being self-similar in its structure. The subdiffusion that emerges in such a high-dimensional, fractal environment leads to a Fokker–Planck Equation with a fractional time derivative. We set up such aso-called fractional Fokker–Planck Equation for the aggregation into granules. From that Fokker–Planck Equation, we derive an expression for the entropy production of a growing granule.
Environmental Taxes and Their Role in the Economics of Sustainable Development
- Paulina Dębniak
2018 Full text Problemy Zarządzania
The purpose of this article is to answer the question of the role of environmental taxes in the economics of sustainable development. The first part of the article discusses the idea of sustainable economic development and the economics of sustainable development. Then, environmental taxes are defined, their essence explained and their role in the economics of sustainable development discussed in theoretical terms, which finally allows for showing the role of these taxes in practice. The fourth part of this article discusses the environmental tax reform. A theoretical and empirical analysis carried out in the article allows us to state that the tax system should play a fundamental role in shaping sustainable economic development, but in practice it is still difficult to carry out the appropriate environmental tax reform.
ENVIRONMENTALLY FRIENDLY MATERIALS IN ARCHITECTURE � MODERN TRENDS AND DEVELOPMENT DIRECTIONS
- Bogusława Konarzewska
- Marek Sztafrowski
2018
For a long time the interest in environmentally friendly materials in architecture is no longer limited to the use of renewable and natural substances such as wood, stone, straw, or reusable materials, such as metals or glass. Today the so-called naturals and the materials compatible with the idea of sustainability constantly appear on the market in new forms. Increasing awareness of the necessity to limit the building sector’s negative impact on the environment at all possible levels changed the way designers, architects and building engineers perceive the materials. Not only do they determine the characteristics of their products, but also try to define the way building materials should be obtained, produced, and delivered to the construction site, as well as utilized or recycled, and having the least negative impact on the environment [1]. The value of materials that can be reused or recycled is rapidly increasing at the same time, due to numerous EU directives on ecological product design principles and international building certification systems such as LEED, BREAM, and others. The dynamic development of materials engineering offers new, ultra-light, durable, great insulating or energy-generating products, aiming at the development of innovative material solutions that could meet the growing demands of investors. Additionally, the materials are environmentally friendly due to their durability and reduced raw material consumption. At the same time many of these materials solutions are inspired by organic patterns found in nature, though not necessarily made from naturals. The latest advances in environmental and human-friendly materials, potentially useful in architecture, construction and design are becoming increasingly easy to access. Due to interdisciplinary technology transfer and numerous material platforms, being kind of global networks in this area, their consulting centers or exhibitions dedicated to new trends in material design, such as "Noble Naturals" in Shanghai in 2017
Enzymy o aktywności aminotransferazy kwasu L-α-aminoadypinowego z Candida albicans - właściwości i rola w metabolizmie komórki grzybowej
- Kamila Rząd
2018 Full text
Candida albicans jest elementem naturalnej flory drobnoustrojowej człowieka. Podobieństwo komórek grzybowych i ssaczych, wzrost częstości występowania infekcji grzybiczych wraz ze stopniowym wzrostem pojawiania się oporności patogenów stwarza potrzebę poszukiwania nowych związków przeciwgrzybowych. Jedną z dróg obraną przez naukowców jest analiza szlaków biosyntezy aminokwasów egzogennych dla człowieka. Przedmiotem badań w ramach rozprawy doktorskiej były enzymy o aktywności α-aminotransferazy L-α-aminoadypinowej (AmAA) ze szlaku biosyntezy L-Lys z C.albicans. Wykazano, że w przypadku C. albicans aktywność AmAA wykazują białka CaAro8p oraz CaAro9p. Białko CaAro8p jest najbardziej wszechstronną aminotransferazą spośród przebadanych. Jest zaangażowane w katabolizm His, Lys, aromatycznych aminokwasów jak również biosyntezę Lys, Phe i Tyr. CaAro9p jest mniej ważnym enzymem uczestniczącym w katabolizmie aromatycznych aminokwasów i Lys, pełni rolę wspomagającą w sytuacji nadmiernej ilości wspomnianych amino kwasów w komórce. Badane aminotransferazy: CaAro8p, CaAro9p, CaYer152Cp, CaBna3p nie pełnią pojedynczo kluczowej roli w żadnym szlaku biosyntezy aminokwasów białkowych w komórce. Usunięcie genów kodujących poszczególne enzymy nie wpłynęło na przeżywalność szczepu, ani na jego procesy biochemiczne czy zjadliwość. Wyklucza to tym samym badane białka, jako istotne cele molekularne w terapii przeciwgrzybowej. Wyniki przedstawionych badań potwierdzają jednak wszechstronność aminotransferaz, stanowiącą podstawę dla żywieniowej elastyczności C. albicans.
E-projektowanie Interdyscyplinarne na przykładzie Inżynierii Medycznej
- Ewa Kozłowska
2018 Full text
W obliczu rozwijającej się technologii w wielu dziedzinach życia coraz częściej spotykamy się z pojęciem współpraca interdyscyplinarna. Podjęcie współpracy jest niezwykle ważnym czynnikiem w projektowaniu nowych rozwiązań technicznych. Szczególnie istotne jest to w przypadku inżynierii medycznej, gdzie kolaboracja inżynierów i lekarzy znacząco wpływa na jakość diagnostyki, rehabilitacji i poprawy jakości życia wielu chorych. Z drugiej strony, stanowi ona niemałe wyzwanie dla przedstawicieli obu profesji. Próby nawiązania współpracy między środowiskiem inżynieryjnym a medycznym niejednokrotnie wiążą się z wieloma nieporozumieniami, problemami i niedogodnościami wynikającymi z rozbieżności tychże środowisk. Tworzenie projektów interdyscyplinarnych z zakresu inżynierii medycznej wymaga licznych konsultacji na każdym etapie projektowania, co często wiąże się z długim wyczekiwaniem na szpitalnych korytarzach. Badania dowodzą, że sama możliwość prowadzenia konsultacji zwiększa poczucie bezpieczeństwa, pobudza kreatywność i redukuje stres, co pozytywnie wpływa na proces projektowania, a dobra komunikacja w środowisku szpitalnym związana z projektowaniem urządzeń medycznych, wprowadzaniem nowych rozwiązań technologicznych oraz szkoleniem personelu przyczynia się do zwiększenia bezpieczeństwa pacjentów, jak również efektywności leczenia. Pojawienie się na rynku licznych narzędzi współpracy online umożliwia przeniesienie konsultacji do chmury i tym samym zredukowanie komplikacji wynikających z konieczności planowania spotkań. E-projektowanie interdyscyplinarne znajduje zastosowanie także w dziedzinach techniczno-medycznych, a przeprowadzone badania dowiodły, że odpowiednio dobrane narzędzia współpracy usprawniają i przyspieszają proces realizacji interdyscyplinarnych projektów z zakresu inżynierii medycznej.
Essential oils as potential anti-staphylococcal agents
- Piotr Szweda
- Magdalena Zalewska
- Joanna Pilch
- Barbara Kot
- Sławomir Milewski
2018 Full text ACTA VETERINARIA-BEOGRAD
Antibiotic therapy of staphylococcal mastitis is characterized by significantly lower cure rates compared to infections caused by other microorganisms. Thus, it is necessary to search for new, alternative, non-antibiotic agents that are effective in the eradication of these bacteria. The aim of our research was to investigate the antimicrobial, especially anti-staphylococcal potential of a large collection (n=36) of essential oils (EOs). Investigation of the antimicrobial activity of tested oils was determined by using a serial, twofold dilution method in 96-wells microtiter plates under conditions recommended by the Clinical and Laboratory Standards Institute (CLSI). The preliminary analysis revealed that six oils, namely: Manuka, Thyme, Geranium, Cedar, Cinnamon (from bark) and Patchouli exhibited the highest activity against reference strains of bacteria. Significant anti-staphylococcal potential of these oils has been also confirmed for a group of 18 Staphylococcus aureus, 8 Staphylococcus epidermidis and 5 Staphylococcus xylosus strains isolated from cases of bovine mastitis. Especially high activity was observed for Cedar, Patchouli, Thyme and Manuka oils. The MIC (Minimal Inhibitory Concentration) values for Patchouli oil were in the concentrations range of 0.01 to 0.313% (v/v). The three other oils inhibited the growth of staphylococci isolated from mastitis in the concentrations range of 0.01 to 0.625% (v/v). Oils isolated from Cinnamomum cassia and Pelargonium graveolens revealed a bit lower, but still satisfactory activity (MIC values in the concentrations range of 0.02 to 1.25% (v/v) and from 0.078 to 1.25% (v/v), respectively). In many cases a slightly higher concentration of oils was required to obtain the bactericidal effect in comparison to growth inhibition. The time – kill kinetic assay revealed that the bactericidal effect was achieved after two hours incubation of the reference strain S. aureus PCM 2051 cells with Thyme oil at concentration equal to 2xMIC (1.25% (v/v)) or MIC (0.625% (v/v)). A slightly lower activity was observed in the case of Cinnamon oil, the bactericidal effect was achieved after 8 hours of incubation. The results of our research clearly indicate that some essential oils exhibit a promising antimicrobial activity and can be considered as alternative antistaphylococcal agents.
Estakada E1 w ciągu obwodnicy Wałcza. Konsekwencje przyjętej technologii sprężenia
- Krzysztof Żółtowski
- Mikołaj Binczyk
- Przemysław Kalitowski
2018
W referacie opisano przypadek liniowej i nieliniowej analizy sprężonego dźwigara mostowego. W czasie budowy zauważono zarysowania na spodniej stronie dźwigara. Były to miejscowe zjawiska zlokalizowane w okolicy połączeń technologicznych. Analiza liniowa modelu belkowego nie dostarczyła informacji o ryzyku zarysowania. Liniowa analiza modelu powłokowego ujawniła naprężenia większe niż wytrzymałość betonu przy rozciąganiu. Nieliniowa materiałowo analiza modelu powłokowego dostarczyła informacji o kształcie i zakresie rys. Studium przypadku pokazało że obliczenia prowadzone na modelu belkowym z dopuszczeniem naprężeń rozciągających powinny być zawsze prowadzone świadomie.
Estakada E2 - kluczowy obiekt Obwodnicy Wałcza
- Krzysztof Żółtowski
- Przemysław Kalitowski
- Piotr Żółtowski
2018 Full text Materiały Budowlane
W artykule przedstawiono uwarunkowania i przebieg projektowania estakady E2 z betonu sprężonego w ciągu Obwodnicy Wałcza. Pokazano efekt procesu optymalizacji projektu pierwotnego. Opisano przeprowadzone analizy wynikające z przyjętej technologii nasuwania podłużnego oraz istotne aspekty, które należy poruszyć przy wyborze tej technologii. Zaprezentowano modele numeryczne konstrukcji przęseł i metodę analizy z uwzględnieniem pracy konstrukcji w fazach budowy. Podkreślono ważną rolę, jaką odegrało zaprojektowanie dziobów montażowych (awanbeków) oraz podano zasady stosowane przy doborze konstrukcji awanbeków i pokazano istotne rezultaty przeprowadzonych analiz.
Estimation of a Stochastic Burgers' Equation Using an Ensemble Kalman Filter
- Mariusz Domżalski
- Zdzisław Kowalczuk
2018
In this work, we consider a difficult problem of state estimation of nonlinear stochastic partial differential equations (SPDE) based on uncertain measurements. The presented solution uses the method of lines (MoL), which allows us to discretize a stochastic partial differential equation in a spatial dimension and represent it as a system of coupled continuous-time ordinary stochastic differential equations (SDE). For such a system it is possible to use the standard estimation methods based on Kalman filtration. In this paper we propose using an ensemble Kalman filter (EnKF), which due to its characteristics can be successfully applied to problems with hundreds of state variables. Finally, we present the simulation results, which confirm the effectiveness of the presented approach.
Estimation of Coherence Bandwidth for Underwater Acoustic Communication Channel
- Iwona Kochańska
- Jan Schmidt
2018
A shallow underwater acoustic communication channel is characterized by strong multipath propagation. The signal reaching the receiver consists of a direct waveform and a number of its delayed and suppressed replica. A significant time dispersion of the transmitted signal and selective fading of its spectrum are observed. Coherence bandwidth defines maximal bandwidth, wherein the channel amplitude characteristic remains constant and its phase characteristic is linear. It is one of the channel transmission parameters that determine the physical layer of data transmission. Coherence bandwidth can be calculated on the basis of the channel impulse response, measured by the correlation method with the use of wideband frequency modulated signals or pseudo-random binary sequences. Both types of probe signals have an impulse-like autocorrelation function whose influence on the impulse response estimate is often considered as negligible. However, probe signals practically used in measuring systems have a limited bandwidth, which causes their correlation properties to be different than in the truly wideband case. This has a direct impact on impulse response and transmission parameters estimates. In particular, the coherence bandwidth can differ significantly depending on the probe signal used. The paper proposes a method of correction of the probe signal influence on the estimate of channel coherence bandwidth.
Estimation of Conservative Contaminant Travel Time through Vadose Zone Based on Transient and Steady Flow Approaches
- Adam Szymkiewicz
- Anna Gumuła-Kawęcka
- Dawid Potrykus
- Beata Jaworska-Szulc
- Małgorzata Pruszkowska-Caceres
- Wioletta Gorczewska-Langner
2018 Full text Water
Estimation of contaminant travel time through the vadose zone is needed for assessing groundwater vulnerability to pollution, planning monitoring and remediation activities or predicting the effect of land use change or climate change on groundwater quality. The travel time can be obtained from numerical simulations of transient flow and transport in the unsaturated soil profile, which typically require a large amount of data and considerable computational effort. Alternatively, one can use simpler analytical methods based on the assumptions of steady water flow and purely advective transport. In this study, we compared travel times obtained with transient and steady-state approaches for several scenarios. Transient simulations were carried out using the HYDRUS-1D computer program for two types of homogeneous soil profiles (sand and clay loam), two types of land cover (bare soil and grass) and two values of dispersion constant. It was shown that the presence of root zone and the dispersion constant significantly affect the results. We also computed the travel times using six simplified methods proposed in the literature. None of these methods was in good agreement with transient simulations for all scenarios and the discrepancies were particularly large for the case of clay loam with grass cover.
Estimation of Failure Initiation in Laminated Composites by means of Nonlinear Six-Field Shell Theory and FEM
- Bartosz Sobczyk
2018
The monography deals with the problem of failure initiation in thin laminated composites. Known techniques of laminate structures modelling are briefly characterised. Eventually, shell based approach is chosen for the purpose of the description of the composite structures behaviour, as it predicts their deformation and states of stress effectively in a global sense. The nonlinear six parameter shell theory (6p theory) with asymmetric strain and stress measures is mainly used within the work and thus its main properties are described. Selected and commonly known methods of the damage onset description for laminated shells, based on the assumption of stress tensor symmetry, named as standard criteria, are studied and analyzed. These are: Tsai-Hill, Tsai-Wu, Hashin and Puck. Modifications of the aforementioned criteria meeting the requirements of the 6p theory are discussed and proposed, since no precise descriptions of the damage initiation in laminates are found in the literature when asymmetric strain and stress components are utilised. The modified criteria, allowing first ply failure (FPF) analysis of laminates, are implemented into non-commercial finite element method (FEM) code CAM. Finally, six numerical examples are solved using FEM to check if the FPF estimations resulting from the application of the standard and the modified criteria differ.
Estimation of Housing Demand with Adaptive Neuro-Fuzzy Inference Systems (ANFIS)
- Olgun Aydin
- Elvan Aktürk Hayat
2018
It has always been important to anticipate the demand for a product. To determine the demand for any product, the parameters such as the economic situation and the demands of the rival products are used generally. Especially in the housing sector, which is the locomotive sector for emerging countries, it is critical to anticipate housing demand and its relationship with economic variables. Because of that, economists, real estate developers, banks, development and economy ministers, and land registry cadastral directorates of the countries have focused on explaining housing demand with economic variables. Therefore, the existence of effective model for prediction is very crucial for policy makers in the sector. For these reasons, the aim of this study is estimating housing demand based on relationship between housing sales transactions and important financial indicators using adaptive neuro-fuzzy inference system (ANFIS).