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Gdańsk University of Technology

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Publications from the year 2023

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  • Optymalizacja doboru prawa konstytutywnego membrany o strukturze plecionej
    • Daniil Reznikov
    2023 Full text

    Celem niniejszej dysertacji jest opracowanie zagadnienia optymalizacyjnego pozwalającego dobrać model konstytutywny opisujący mechaniczne zachowanie membrany technicznej. Do analizy wybrano membrany plecione, stosowane w medycynie, tzw. siatki chirurgiczne. W celu wykonania identyfikacji praw konstytutywnych, wykonano dwuosiowe rozciąganie próbek materiałów, otrzymując wskazanie na nieliniowe anizotropowe zachowanie materiałów. W wyniku tego, do opisania zależności pomiędzy naprężeniem, a odkształceniem przyjęto teorię hipersprężystości. Przeprowadzone z różnymi sterowaniami testy mechaniczne próbek doprowadziły do uzyskania różnych kompletów parametrów rozważanych praw konstytutywnych. W celu identyfikacji prawa opisującego pracę materiałów w warunkach naturalnych przeprowadzono analizę optymalizacyjną w której funkcja celu odnosi się do pozycji maksymalnej reakcji podporowej wyznaczonej w modelu numerycznym implantu oraz do pozycji maksymalnej reakcji wyznaczonej eksperymentalnie. Przeprowadzona analiza wskazuje, że model konstytutywny membrany plecionej silnie zależy od rodzaju wykonanego testu mechanicznego materiału, a wybór prawa opisującego rzeczywistą pracę danego materiału może być zrobiony w odniesieniu do eksperymentu z symetrycznym obciążeniem danego materiału.

  • Optymalizacja zasobów chmury obliczeniowej z wykorzystaniem inteligentnych agentów w zdalnym nauczaniu
    • Piotr Dryja
    2023 Full text

    Rozprawa dotyczy optymalizacji zasobów chmury obliczeniowej, w której zastosowano inteligentne agenty w zdalnym nauczaniu. Zagadnienie jest istotne w edukacji, gdzie wykorzystuje się nowoczesne technologie, takie jak Internet Rzeczy, rozszerzoną i wirtualną rzeczywistość oraz deep learning w środowisku chmury obliczeniowej. Zagadnienie jest istotne również w sytuacji, gdy pandemia wymusza stosowanie zdalnego nauczania na dużą skalę lub rosnące koszty efekty ograniczają naukę stacjonarną. W dysertacji opracowano model alokacji inteligentnych agentów pedagogicznych, modułów systemu zdalnego nauczania oraz solwerów do serwerów w chmurze. Sformułowano zagadnienie wyznaczania reprezentacji rozwiązań Pareto-optymalnych. Opracowano wielokryterialny algorytm ewolucji różnicowej, za pomocą którego minimalizuje się cztery kryteria takie, jak: obciążenie CPU newralgicznego hosta, obciążenie komunikacyjne krytycznego węzła, koszt serwerów oraz łączny pobór mocy elektrycznej. W celu eksperymentalnej weryfikacji poprawności modelu zaprojektowano demonstrator chmury edukacyjnej w oparciu o wybrane zasoby Politechniki Gdańskiej oraz Politechniki Warszawskiej. Przeprowadzono wielowariantowe symulacje migracji inteligentnych agentów w środowisku Moodle na platformie OpenStack. Eksperymenty numeryczne potwierdziły, że wykorzystanie wielokryterialnej metaheurystyki opartej na ewolucji różnicowej umożliwia wyznaczenie wyższej jakości rozwiązań niezdominowanych niż rozwiązania uzyskane za pomocą innych metaheurystyk, takich jak: algorytm ewolucyjny, programowanie genetyczne, algorytm wyszukiwania harmonii oraz algorytm roju cząstek.

  • Organic Supercritical Thermodynamic Cycles with Isothermal Turbine
    • Marian Piwowarski
    • Krzysztof Kosowski
    • Marcin Richert
    2023 Full text ENERGIES

    Organic Rankine cycles (ORC) are quite popular, but the overall efficiencies of these plants are rather very low. Numerous studies have been conducted in many scientific centers and research centers to improve the efficiency of such cycles. The research concerns both the modification of the cycle and the increase in the parameters of the medium at the inlet to the turbine. However, the efficiency of even these modified cycles rarely exceeds 20%. The plant modifications and the optimization of the working medium parameters, as a rule, lead to cycles with the high pressure and high temperature of live vapor and with a regenerator (heat exchanger) for the heating, vaporization and superheating of the medium. A new modified cycle with supercritical parameters of the working medium and with a new type of turbine has been described and calculated in the paper. For the first time, the isothermal turbine is proposed for supercritical organic cycles, though this solution is known as the Ericsson cycle for gas turbines. The innovative cycle and the usual ORC plants are characterized by almost identical block diagrams, while in the proposed cycle, the work of the turbine is obtained as a result of isothermal expansion and not in an adiabatic process. The analysis has been performed for 11 different working media and two cycles. The calculations have shown that power plants with isothermal expansion achieve better efficiency than cycles with adiabatic turbines. For example, the rise in efficiency changes from 8 percentage points for R245fa up to 10 percentage points for acetone. The calculations have proved that it is possible to obtain efficiency exceeding 50% for organic power plants. This is an outstanding result compared with modern steam and gas turbine units.

  • Orientation-aware ship detection via a rotation feature decoupling supported deep learning approach
    • Xinqiang Chen
    • Hao Wu
    • Bing Han
    • Wei Liu
    • Jakub Montewka
    • Ryan Wen Liu
    2023 ENGINEERING APPLICATIONS OF ARTIFICIAL INTELLIGENCE

    Ship imaging position plays an important role in visual navigation, and thus significant focuses have been paid to accurately extract ship imaging positions in maritime videos. Previous studies are mainly conducted in the horizontal ship detection manner from maritime image sequences. This can lead to unsatisfied ship detection performance due to that some background pixels maybe wrongly identified as ship contours. To address the issue, we propose a novel rotational you only look once (YOLO) based model (RYM) to accurately yet fast detect ships from maritime images by considering ship rotation angle. The proposed RYM model are designed to detect tilted ships from images with the help of a rotation decoupled (RD) head, attentional mechanism and bidirectional feature network (BiFPN). The experimental results suggested that RYM can obtain satisfied ship detection performance considering that average accuracy reaches 96.7%. The precision and recall indicators are 93.2% and 94.7%, respectively. The proposed framework can be applied into real-time ship detection task due to that the processing speed is 45.6 frames per second (FPS).

  • Orunia # PRZYSTANEK W PODRÓŻY wystawa projektowych prac studenckich
    • Agnieszka Kurkowska
    • Alicja Karaś
    2023

    Podróżujemy. Lokalnie i pokonując granice. Przenosimy się z potrzeby i konieczności. Przenosimy się w czasie I w wyobraźni. Przywołujemy wspomnienia, marzymy. Podróż wymaga przystanków: czasu wypoczynku i czasu refleksji. Podróż przez życie wymaga od nas stworzenia zrównoważonego schronienia dla naszej fizycznej egzystencji. Nikt z nas nie istnieje w odosobnieniu. Otacza nas przyroda, dotyczy dziedzictwo, które współtworzymy, dotykają codzienne problemy. łączy troska o planetę. Wspólny system wartości i dążenia kierunkują naszą podróż. Spotykamy w niej innych ludzi i przyglądamy się samym sobie. Studenci przygotowali propozycje obiektów architektonicznych ulokowanych na terenie Oruni, które są „PRZYSTANKAMI W PODRÓŻY”.

  • Osteoblast and bacterial cell response on RGD peptide‐functionalized chitosan coatings electrophoretically deposited from different suspensions on Ti13Nb13Zr alloy
    • Łukasz Pawłowski
    • Szymon Mania
    • Adrianna Banach-Kopeć
    • Michał Bartmański
    • Anna Ronowska
    • Kacper Jurak
    • Aleksandra Mielewczyk-Gryń
    • Natalia Karska
    • Sylwia Rodziewicz-Motowidło
    • Andrzej Zieliński
    2023 Full text JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART B-APPLIED BIOMATERIALS

    Metallic materials for long-term load-bearing implants still do not provide high antimicrobial activity while maintaining strong compatibility with bone cells. This study aimed to modify the surface of Ti13Nb13Zr alloy by electrophoretic deposition of a chitosan coating with a covalently attached Arg-Gly-Asp (RGD) peptide. The suspensions for coating deposition were prepared in two different ways either using hydroxyacetic acid or a carbon dioxide saturation process. The coatings were deposited using a voltage of 10 V for 1 min. The prepared coatings were examined using SEM, EDS, FTIR, and XPS techniques. In addition, the wettability of these surfaces, corrosion resistance, adhesion of the coatings to the metallic substrate, and their antimicrobial activity (E. coli, S. aureus) and cytocompatibility properties using the MTT and LDH assays were studied. The coatings produced tightly covered the metallic substrate. Spectroscopic studies confirmed that the peptide did not detach from the chitosan chain during electrophoretic deposition. All tested samples showed high corrosion resistance (corrosion current density measured in nA/cm2). The deposited coatings contributed to a significant increase in the antimicrobial activity of the samples against Gram-positive and Gram-negative bacteria (reduction in bacterial counts from 99% to, for CS-RGD-Acid and the S. aureus strain, total killing capacity). MTT and LDH results showed high compatibility with bone cells of the modified surfaces compared to the bare substrate (survival rates above 75% under indirect contact conditions and above 100% under direct contact conditions). However, the adhesion of the coatings was considered weak.

  • Overcoming Challenges of Virtual Scrum Teams: Lessons Learned Through an Action Research Study
    • Jędrzej Babło
    • Bartosz Marcinkowski
    • Adam Przybyłek
    2023

    After the COVID-19 breakout, agile teams found themselves in situations that “pure agilists” and textbooks on agile methods had preferred to ignore. Whereas agile mindsets helped them to quickly shift to remote work, mere virtualization of agile practices often proved insufficient, and several challenges emerged. This paper reports on an Action Research project carried out in Lufthansa Systems Poland with the aim of (1) revisiting their ad-hoc actions to adapt to remote work; and (2) elaborating systematic solutions to maintain efficiency in such a setting. With our assistance, the participating teams found measures to mitigate issues posed by the new work environment. They devised an inter-team communication model to improve the effectiveness of information exchange that had declined in the absence of spontaneous, face-to-face communication. Moreover, they employed several other mitigation strategies, including working at least one day per week in the office, keeping webcams on during online meetings, and recapping meetings at the end of a session. Our study largely supports previous findings indicating that Scrum can be effectively applied beyond its comfort zone but also suggests that for adaptations to be successful and comprehensive, they should be developed in a structured manner.

  • Overview of new product development strategies and models
    • Alina Guzik
    2023 Full text Catallaxy

    Motivation: The motivation for the overview presented in this article is to provide a starting point for considering whether existing new product development methodology and its level of detail allows product teams to develop high-quality and business-effective product concepts. Aim: The aim of this article is recognise the current state of research into new product development methodology and to present the strategies and models for New Product Development (NPD). Materials and methods: The systematic review of the literature was applied in the article. Results: The first section outlines the main strategies for new product development and how they are divided by methodological stance, degree of planning, search pattern, focus and response. The second part discusses the known models of new product development including: the craft model and the 5 generations based on the innovation models described by Rothwell and the stages of the manufacturing process defined in the literature. Part four looks at new trends in new product development, including: Open Innovation, Rapid Product Development (RPD), Agile New Product Development (ANPD), Sustainable New Product development (SNPD), the Design Thinking method and the new technologies of Industry 4.0.

  • Overview of the Synthesis and Catalytic Reactivity of Transition Metal Complexes Based on C═P Bond Systems
    • Aleksandra Ziółkowska
    • Doroszuk Justyna
    • Łukasz Ponikiewski
    2023 Full text ORGANOMETALLICS

    This report provides an overview of the use of phosphaalkenes (C=P) in syntheses of various complexes. Going through successive complexes containing the d-block metals, we sought how this area of chemistry was formed over the years. Additionally, this work contains information on the possible coordination types and means of constructing the complexes. In addition, this review reveals the reactivities of phosphaalkene complexes with a strong emphasis on catalytic properties.

  • Oxide nanoparticle exsolution in Lu-doped (Ba,La)CoO3
    • Daria Balcerzak
    • Iga Szpunar
    • Ragnar Strandbakke
    • Sarmad W. Saeed
    • Calliope Bazioti
    • Aleksandra Mielewczyk-Gryń
    • Piotr Winiarz
    • Alfonso Carrillo
    • Maria Balaguer
    • José M Serra
    • Maria Gazda
    • Sebastian Wachowski
    2023 CRYSTENGCOMM

    This study investigated Lu doping of Ba0.5La0.5CoO3 and its influence on the exsolution of oxide nanoparticles (NPs). As a result of Lu doping, we observed the phase segregation into the main Ba0.4La0.6Co0.85Lu0.15O3 (BLCO–Lu) phase and the secondary Ba0.85La0.15Co0.75Lu0.25O3 (BCO–Lu) phase. We noticed the exsolution of BCO–Lu nanoparticles on the main BLCO–Lu phase. Moreover, the BLCO–Lu phase exsolved in the form of nanoparticles on the adjacent BCO–Lu grains. That shows that the phases are covered with mutually exsolved oxide NPs. In addition, trace amounts of the BaLuCo4O7 phase are detected. We noticed that the exsolved oxides even in the as-prepared sample were fine (average size of 18 nm), and well distributed with a dense population of NPs above 280 per 1 μm2. Furthermore, we showed that the size and shape of the exsolved oxide NPs can be controlled by varying the annealing temperature. For example, at 800 °C the exsolved oxides segregate and form two different shapes; spherical and cuboidal, with an average size of 31 nm and NP population of about 23 NPs per μm2. Meanwhile, with lowering the temperature to 400 °C the oxides form only spherical and quite evenly distributed NPs with the occurrence of 137 NPs per 1 μm2. The obtained results open the possibility of tailoring a novel, more catalytically active material for future applications in electrochemical devices.

  • Oxygen vacancy-enriched V2O5·nH2O nanofibers ink for universal substrates-tolerant and multi means-integratable NH3 sensing
    • Xiaxia Xing
    • Xinhua Zhao
    • Zhenxu Li
    • Lingling Du
    • Chen Wang
    • Dongliang Feng
    • Dongsheng Geng
    • Robert Bogdanowicz
    • Dachi Yang
    2023 CHEMICAL ENGINEERING JOURNAL

    Universal substrates-tolerant and multi means-integratable ammonia (NH3) sensing is highly desired in future Internet of Things in environmental monitoring, food security and early diagnosis of human diseases, however, is still less than satisfactory. Here, an oxygen vacancy-governed NH3 sensing has been developed with V2O5·nH2O nanofibers (NFs) ink, via combined thermal decomposition of ammonium metavanadate and dilution. As-obtained NH3 sensing ink takes on red colloids, in which the V2O5·nH2O NFs around 14 nm in diameter are interconnected. Beneficially, the fabric fiber decorated with V2O5·nH2O NFs ink displays excellent selectivity and ppb-concentration detection limit. Remarkably, V2O5·nH2O NFs ink is integrated over “hard” and “flexible” substrates such as glass, wood, paper, leaf and fabric with excellent tolerance by multi-integratable means such as writing, dipping and sewing. Theoretically, such NH3 sensing is interpreted that the bonding between V2O5 NFs and H2O modulates oxygen vacancy and thus adsorption sites, and the incorporation between crystal water and free one contributes to stable ink. Practically, A sensing device built with V2O5·3.1H2O NFs ink has been simulated to communicate with a smartphone with reliable NH3 sensing.

  • Oznaczanie zanieczyszczeń pierwiastkowych w wyrobach ceramicznych wytwarzanych z dodatkiem różnych odpadów poprodukcyjnych
    • Aleksandra Liczbińska
    • Bartłomiej Cieślik
    2023 Full text Analityka: Nauka i Praktyka

    Niektóre odpady zawierające związki toksyczne mogą zostać immobilizowane w nierozpuszczalnej matrycy materiału poprzez zmieszanie odpadów z materiałami stanowiącymi podstawowe surowce w producji

  • P92 steel and inconel 617 alloy welds joint produced using ERNiCr-3 filler with GTAW process: Solidification mechanism, microstructure, mechanical properties and residual stresses
    • Amit Kumar
    • Shailesh M. Pandey
    • Sachin Sirohi
    • Dariusz Fydrych
    • Chandan Pandey
    2023 Heliyon

    The objective of the current study was to analyse the microstructure, mechanical characteristics, and residual stresses of a dissimilar welded joint (DWJ) made of P92 steel and the Inconel alloy 617 (IN617) using the gas tungsten arc welding (GTAW) method. The ERNiCr-3 filler was selected to produce the conventional V groove (VG) and narrow V groove (NVG) butt joint. The filler deficient zones in the weldments, such as the filler deficient beach, i.e. unmixed zone (UZ), peninsula, and island, as well as the distinct heat-affected zone (HAZ), were visible near the interface of ERNiCr-3 filler weld and P92 steel due to the distinct differences in the chemical composition, microstructure, and mechanical properties between the filler and P92 base metal (BM). A very narrow partial melted zone (PMZ) and almost negligible UZ and HAZ were noticed at the interface of IN617 and ERNiCr-3 weld metal and it occurred mainly due to the similarity in microstructure and melting point. The austenitic microstructure of ERNiCr-3 filler weld was accompanied by precipitates enriched with Ti and Nb along with the inter-dendritic space. At room temperature, the mechanical properties of both the groove joints were evaluated, and the test results indicated that the welded joint satisfied the standard requirements for AUSC power plants' boiler applications. The tensile test results showed the failure from ERNiCr-3 filler weld with a tensile strength of 627 ± 2 MPa and 636 ± 3 MPa for VG and NVG welded joints, respectively. A poor weld metal impact toughness in comparison to the BMs was attributed to the presence of the brittle Ti(C, N) and Nb(C) particles in the interdendritic space. The impact toughness for the NVG weld joint was measured higher than for the VG weld joint. A significant hardness deviation was measured along the weldments that might be due to heterogeneous microstructure, i.e. UZ, HAZ, delta ferrite, and weld metal. To impart the ductility and temper the martensite in P92 HAZ, post-weld heat treatment (PWHT) was also performed, and a studied their effect on microstructure evolution across the weldments and mechanical properties. Groove design also showed a significant effect on residual stress variation. In comparison to conventional VG joints, the NVG joints exhibited superior mechanical properties and lower residual stress values.

  • Paintings
    • Krzysztof Wróblewski
    2023

    The painting as a curtain (...) A contradiction is therefore what constitutes a painting, and ambiguity is its right. As a young artist, I intuitively defined the work of art as a boundary. Over the years that intuition changed into a conviction that the particular form of art which is painting at the same time reveals and hides; it exists at this intersection of functions as a see-through curtain. We don’t know why there are some paintings which we constantly want to have before our eyes and others which we quickly forget. We will never have a complete answer to the question ‘what is a painting?’, because it resists being put into words – it is a part of a cloud, an element of a fog, from which multiplied imagery emerges. We give in to the charm of the curtain, but fictions are nothing bad. Thanks to the ability to create fictions and to believe in them we conquered the world. The reality, however we choose to define it, is woven with pictures. Krzysztof Wróblewski

  • Palmiarnia / Gdańsk
    • Joanna Kabrońska
    2023 Full text Architektura-Murator

    Palmiarnia w Parku Oliwskim zyskała nową formę w wyniku rozpoczętego w 2016 roku procesu rewitalizacji, podjętego w celu ochrony zabytkowych budynków, dostosowania ich do obecnych wymagań, a przede wszystkim podkreślenia kulturowych wartości dawnego ogrodu opackiego. Efektem prac rewitalizacyjnych jest dynamiczna, przejrzysta forma, zbudowana z zastosowaniem nowych technologii. Rotunda wraz z odrestaurowaną zabytkową oranżerią wpisuje się w poszukiwania przyszłej - odpowiadającej pojawiającym się wyzwaniom - roli Parku Oliwskiego, dając początek nowej interpretacji tego wyjątkowego miejsca.

  • Panopticum 1.0 Curator's choice
    • Jan Buczkowski
    2023

    Wystawa zbiorowa 7 artystów współpracujących z galerią jest kuratorskim wyborem prac w których dominującymi kolorami są czerń i biel. Kuratorem wystawy jest Natalia Bimer

  • Paradoxes in the engineering change management process
    • Jakub Tryczak
    • Anna Lis
    • Paweł Ziemiański
    2023 Full text Zeszyty Naukowe. Organizacja i Zarządzanie / Politechnika Śląska

    Purpose: The main purpose of this paper is to conceptualize and operationalize paradoxes that are significant in the engineering change management (ECM) process. The following research question was stated: What are the paradoxes that influence the ECM process, and how can they be measured? Design/methodology/approach: The study is divided into two parts: conceptualization and operationalization. Conceptualization involved a literature review, which allowed for identifying initial categories of paradoxes that were later verified during in-depth personal interviews with the study participants. The subsequent operationalization involved developing a measurement tool which is a semantic differential scale that allows for assessing the perceived current and desired approach to solving paradoxes affecting ECM. The tool was revised based on in-depth personal interviews with participants of the ECM process. For the study, a manufacturing company which implemented a change management process was selected. Findings: Four general groups of paradoxes previously identified in the paradox theory literature (i.e. learning, belonging, performing, and organizing) were used to develop a list of paradoxes specific to the ECM process. In-depth interviews allowed to obtain data from experienced participants of the process, which was used to verify the preliminary list. The result of this verification was the list of 12 paradoxes that was included in the final measurement tool. Research limitations: Even though the study involved well-informed participants who are experienced in the ECM process, they represented a single company. Additionally, the proposed research tool may require further verification in subsequent studies. Practical implications: The knowledge regarding paradoxes specific to the ECM process and the created tool can be helpful for change administrators, project managers, and other stakeholders. They allow to define the areas of most significant tensions in the ECM process that require attention and effort. Originality/value: This paper's main value pertains to two different domains- cognitive and methodic. The undertaken attempt to include paradoxes and their significance in the analysis of the ECM process broadens the current understanding of process determinants. The proposed research tool, which is based on a well-grounded theoretical approach to paradoxes and adapted to fit the ECM process, can be used in further research.

  • Parallel implementation of a Sailing Assistance Application in a Cloud Environment
    • Marcin Życzkowski
    • Rafał Szłapczyński
    • Piotr Orzechowski
    • Henryk Krawczyk
    2023 Full text IEEE Access

    Sailboat weather routing is a highly complex problem in terms of both the computational time and memory. The reason for this is a large search resulting in a multitude of possible routes and a variety of user preferences. Analysing all possible routes is only feasible for small sailing regions, low-resolution maps, or sailboat movements on a grid. Therefore, various heuristic approaches are often applied, which can find solutions within an acceptable time, sacrificing their optimality and accuracy. In this study, we propose a different approach based on the parallel implementation of an exact algorithm. Specifically, we present a Sailing Assistance Application (SAA) utilizing a deterministic approach and show how it can be parallelized in a cloud environment to reduce its execution time. The potential of the proposed parallelization method goes beyond the particular presented solution; it can be used to improve the performance of other weather routing tools such as collision avoidance and related applications.

  • Peculiarities of measurement uncertainty evaluation at calibrating a ring gauge
    • Igor Zakharov
    • Olesia Botsiura
    • Dimitar Diakov
    • Dariusz Świsulski
    2023

    Example S13 from EA-4/02 M:2013 “Calibration of a ring gauge with a nominal diameter of 90 mm” is analyzed. The report uses the kurtosis method and the law of propagation of expanded uncertainty developed by the authors to the expanded uncertainty evaluation. It is shown that the introduction of a coaxiality correction for the ring gauge and the measuring axis of the comparator leads to the need to estimate its standard measurement uncertainty using the second-order terms of the Taylor series and taking into account the kurtosis of input quantities using the method of partial increments. A good agreement between the results obtained by applying the described procedure and the results obtained by the Monte Carlo method is shown.

  • Peer assessment as a method for measuring harmful internet use
    • Waldemar W. Koczkodaj
    • Alicja Kowalczyk
    • Mirosław Mazurek
    • Witold Pedrycz
    • Grzegorz Redlarski
    • Elżbieta Rogalska
    • Dominik Strzałka
    • Agnieszka Szymańska
    • Antoni Wilinski
    • Songwen Xue
    2023 Full text MethodsX

    Harmful Internet use (HIU) describes unintended use of the Internet. It could be both self-harm and harming others. Our research goal is to develop a more accurate method for measuring HIU by this novel peer assessment. As such, it may become, with our call for more research, a paradigm shift supplementing every rating scale or other type of Internet use assessment. In addition to classic statistical analysis, structural equations have been employed. Results indicate that the true positive rate (TPR) is substantially higher than assessed in other studies.