Repozytorium publikacji - Politechnika Gdańska

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Repozytorium publikacji
Politechniki Gdańskiej

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  • Joint foreign ownership and global value chains effects on productivity: a comparison of firms from Poland and Germany
    • Sabina Szymczak
    • Aleksandra Parteka
    • Joanna Wolszczak-Derlacz
    2023 Pełny tekst International Journal of Emerging Markets

    Purpose The study aims to examine the joint effects of foreign ownership (FO) and involvement in global value chains (GVCs) on the productivity performance of firms from a catching-up country (Poland) and a leader economy (Germany). Design/methodology/approach The authors use micro-level data on firms combined with several sector-level GVC participation measures. The authors investigate whether the link between productivity and the overall sectoral degree of involvement in global production structures depends on a firm's ownership. The authors verify the robustness of the obtained results by using an instrumental variables approach and weighted regression. Findings The results show that domestically owned firms are less productive than foreign ones, which is particularly true at low GVC participation levels. However, as GVC involvement increases, the FO productivity premium decreases, leading to productivity catching up between foreign and domestically owned firms. This mechanism is similar in Poland and Germany. However, in the leader country (Germany), the productivity performance of domestically owned firms is more stable along the distribution of GVC involvement. Originality/value This study contributes to the foreign direct investment (FDI)–productivity literature by comparing the catching-up and developed countries' perspectives and incorporating the productivity–GVC relationship into the FDI analysis. The authors show that the FO premium is not confined to the developing context but is also present in a leader country. Moreover, the link between productivity and the overall sectoral degree of involvement in global production structures depends on a firm's ownership.

  • Kagome Lattice Promotes Chiral Spin Fluctuations
    • Kamil Kolincio
    • Max Hirschberger
    • Jan Masell
    • Taka-hisa Arima
    • Naoto Nagaosa
    • Yoshinori Tokura
    2023 Pełny tekst PHYSICAL REVIEW LETTERS

    Dynamical spin fluctuations in magnets can be endowed with a slight bent toward left- or right-handed chirality by Dzyaloshinskii-Moriya interactions. However, little is known about the crucial role of lattice geometry on these chiral spin fluctuations and on fluctuation-related transport anomalies driven by the quantum-mechanical (Berry) phase of conduction electrons. Via thermoelectric Nernst effect and electric Hall effect experiments, we detect chiral spin fluctuations in the paramagnetic regime of a kagome lattice magnet; these signals are largely absent in a comparable triangular lattice magnet. Supported by Monte Carlo calculations, we identify lattices with at least two dissimilar plaquettes as most promising for Berry phase phenomena driven by thermal fluctuations in paramagnets.

  • Kapitał marki miasta Gdańska - ujęcie marketingowe
    • Anna Dziadkiewicz
    • Ewelina Sokołowska
    • Piotr Juchniewicz
    2023

    Kapitał marki miasta obejmuje zestaw jego unikalnych cech, które umożliwiają rywalizowanie o potencjalnych klientów: mieszkańców, turystów, studentów czy też inwestorów. Niniejszy rozdział dotyczy problematyki czynników kształtujących markę miasta Gdańsk określonych na podstawie wyników badania jakościowego. Zostało ono przeprowadzone w formie wywiadu z ekspertami zajmującymi się zawodowo kreowaniem marki miast. Wyboru respondentów dokonano zgodnie z założeniami teorii ugruntowanej, która opiera się na przesłance, że rzeczywistość społeczną najlepiej rozumieją podmioty w nią zaangażowane. Uzyskane odpowiedzi umożliwiły stworzenie mapy prezentującej zależności dotyczące kapitału marki miasta Gdańsk. Rezultaty badania mogą być wykorzystane przez organy zajmujące się budowaniem wizerunku miasta, wpływając na ulepszanie jego oferty, doskonalenie komunikacji z interesariuszami a także na ocenę działań marketingowych mających na celu rozwój marki miasta Gdańsk.

  • Karhunen-Loeve-based approach to tracking of rapidly fading wireless communication channels
    • Maciej Niedźwiecki
    • Artur Gańcza
    2023 SIGNAL PROCESSING

    When parameters of wireless communication channels vary at a fast rate, simple estimation algorithms, such as weighted least squares (WLS) or least mean squares (LMS) algorithms, cannot estimate them with the accuracy needed to secure the reliable operation of the underlying communication systems. In cases like this, the local basis function (LBF) estimation technique can be used instead, significantly increasing the achievable tracking accuracy. We show that when some prior knowledge of statistical properties of parameter changes is available, such as the bandwidth of their variation, both the type and the number of basis functions, used in the LBF approach to approximate time-varying channel parameters, can be optimized using the Karhunen-Loève (KL) decomposition based technique.

  • KASZUBSKIE KWIATY. ogrody i tradycja: żywe dziedzictwo. warsztaty w ramach Bałtyckiego Festiwalu Nauki
    • Agnieszka Kurkowska
    2023

    Warsztaty dla dzieci dotyczyły tradycyjnych ogrodów i przedogrodków kaszubskich - ważnego elementu kultury regionalnej i dziedzictwa. Kwiaty odgrywają w nich rolę kluczową, bo poza właściwościami użytkowymi rośliny stanowią inspirację wzorniczą. Dzieci posadziły nasiona malwy - kwiatu o wyjątkowym pięknie i szerokim zastosowaniu w kuchni i medycynie naturalnej. Wypartej przez powszechnie dostępne, popularne gatunki roślin ogrodniczych Celem było zrozumienie i podtrzymanie tradycji lokalnej.

  • Keratin-Butyrate Scaffolds Promote Skin Wound Healing in Diabetic Rats Through Down-Regulation of IL-1β and Up-Regulation of Keratins 16 and 17
    • Marek Konop
    • Mateusz Rybka
    • Mateusz Szudzik
    • Łukasz Mazurek
    • Anna Laskowska
    • Dorota Sulejczyk
    • Zbigniew Ruszczak
    • Rafał Mazgaj
    • Bartłomiej Cieślik
    • Robert Schwartz
    • Emilia Samborowska
    • Jakub Frankowski
    • Adam Waszkowski
    • Piotr Konopelski
    • Joanna Czuwara
    2023 Pełny tekst Journal of Natural Fibers

    Impaired wound healing particularly in diabetics creates a significant healthcare burden. The study aimed to evaluate the effect of keratin-butyrate fibers (FKDP +0.1%NaBu) in a full-thickness skin wound model in 30 diabetic rats. Physicochemical examination showed that the obtained dressing possesses a heterogeneous structure and butyrate was slowly released into the wound. Moreover, the obtained dressing is nontoxic and supports cell growth. In vivo results showed that keratin-butyrate dressing accelerated wound healing on days 4 and 7 post-injury (p < .05). Histopathological and immunofluorescence examination revealed that applied dressing stimulated macrophage infiltration, which favors tissue remodeling and regeneration. The dressing was naturally incorporated into regenerating tissue. The highest mRNA expression level of interleukin 1β (IL-1β) was observed during the first 2 weeks in the control wounds compared to FKDP +0.1%NaBu treated wounds, in which IL-1β was significantly decreased. In FKDP +0.1%NaBu dressed wounds, mRNA expression of IL-10 and VEGF increased significantly (p < .05) from day 14. Keratin-butyrate treated wounds enhanced mRNA expression of keratin 16 and 17 and zonula occludens protein-1 and junctional adhesion molecules (p < .05) on days 14, 21, and 28 post-injuries. Our study showed that keratin butyrate dressing is safe and can efficiently accelerate skin wound healing in diabetic rats.

  • Key activities to improve energy management in DC microgrids connected by urban traction
    • Kawsar Nassereddine
    • Marek Turzyński
    • Mykola Lukianov
    • Natalia Strzelecka
    2023 Pełny tekst Przegląd Elektrotechniczny

    DC MicroGrids must have Energy Management Systems to guarantee efficient, dependable, and environmentally friendly electricity. The application of Model Predictive Control, proved to be helpful due to its adaptability and capacity to use non-linear models. This paper, based on an extensive literature review, identifies and discusses the three key activities to improve the characteristics of DC MicroGrids, i.e.: the use of Energy Storage Systems), the implementation of Demand Side Management, and the use of Model Predictive Control.

  • Kinetics of Intermetallic Phase Precipitation in Manual Metal Arc Welded Duplex Stainless Steels
    • Monika Orłowska
    • Krzysztof Pańcikiewicz
    • Aleksandra Świerczyńska
    • Michał Landowski
    2023 Pełny tekst Materials

    The article presents the influence of heat treatment on the kinetics of transformations in lean duplex LDX2101 steel and a weld made of standard duplex 2209 material, which was welded by manual metal arc welding. Changes in the microstructure, hardness, and magnetic phase content were analyzed after heat treatment was conducted at a temperature of 800 °C for a period ranging from 15 to 1440 min. Light and scanning microscopy, Vickers hardness measurements, and magnetic phase content measurements using a ferritoscope were used for the research. In the LDX2101 steel, the presence of δ-ferrite and γ austenite was identified and additional Cr2N nitrides were observed in the heat-affected zone. After heat treatment, the decomposition of δ ferrite into γ2 austenite and Cr2N nitrides was observed in both areas. In the case of weld made by the coated electrode in 2209 grade, a ferritic–austenitic microstructure with allotriomorphic austenite (γA), Widmanstätten austenite (γW), and idiomorphic austenite (γI) and δ-ferrite area with “bee swarms” of fine precipitations of chromium nitrides Cr2N and non-metallic inclusions (NMIs) of slag, formed during the welding process, are observed in the as-welded state. After heat treatment, the presence of the χ phase (after 15 min of annealing) and the σ phase (after 120 min of annealing) was additionally identified. The kinetics of intermetallic phase evolution in welds made from 2209 material were presented. The obtained results of hardness measurements and metallographic tests were correlated, which allowed for a quick check of the precipitation processes on the used element.

  • Klasyczne wzorce urbanistyczne w „miastach tymczasowych” na przykładzie skautowych zlotów Jamboree
    • Oskar Amiri
    2023 Pełny tekst

    Przedmiotem dysertacji są klasyczne wzorce urbanistyczne w „miastach tymczasowych”, analizowane na przykładzie skautowych zlotów Jamboree, czyli międzynarodowych wydarzeń edukacyjnych dla skautów i skautek, gromadzących kilkanaście lub kilkadziesiąt tysięcy ludzi przez okres około dwóch tygodni. W rozprawie przyjęto perspektywę miasta „tymczasowego”, a zatem formy miejskiej funkcjonującej w pewnych ramach czasowych. Założono, że skautowe zloty Jamboree wpisują się w definicję „miasta tymczasowego” zarówno w zakresie funkcji czasu, jak i celu. W rozprawie przedstawiono rozumienie pojęcia klasycznych wzorców urbanistycznych, wyróżniając trzy kategorie: formy przestrzenne, przestrzenie funkcjonalne i ład przestrzenny. Podstawą analizy ich obecności były materiały kartograficzne projektów zagospodarowania terenu skautowych zlotów Jamboree oraz wnioski z badań społecznych. Pomimo różnic dotyczących rozpoznania poszczególnych klasycznych wzorców urbanistycznych, w każdym z analizowanych przykładów były one identyfikowane i na ogół oceniane pozytywnie. Z analiz i badań wynika, że wzorce urbanistyczne, takie jak np. rynek, ulica, porządek geometryczny, stanowią istotne elementy nie tylko krajobrazu przestrzenno-kulturowego, lecz dotyczą także mniej lub bardziej trwałych warunków życia w tymczasowych strukturach miejskich. Obecność klasycznych wzorców urbanistycznych w „miastach tymczasowych” oraz w świadomości ich użytkowników dowodzi pewnej uniwersalności tych cech oraz potrzeby ładu i harmonii w organizacji przestrzeni miejskiej.

  • KM Challenges in Small KIBS Companies: Multi-case Analysis in Two Countries
    • Ettore Bolisani
    • Tomas Cherkos Kassaneh
    • Anna Lis
    • Enrico Scarso
    • Ewa Stolarek-Muszyńska
    • Małgorzata Zięba
    2023 Pełny tekst

    Knowledge Intensive Business Services (KIBS) – i.e. companies like e.g. computer services, consulting, engineering, business communication, and R&D support - are key players in the modern economies. They stimulate the innovativeness of businesses and societies. Their competitiveness is based on knowledge, which is their key production factor and also the kind of “goods” they sell. The large majority of KIBS companies have a small or medium size, which leads to major challenges because they manage their cognitive assets in a substantially informal and undeliberate way. They face several obstacles to managing knowledge, partly due to their limited resources, but also to the knowledge-intensive and intangible nature of their business processes and outputs. Such challenges, when not successfully identified and faced, may negatively impact competitiveness. The paper illustrates the findings of a qualitative investigation aimed at exploring the main KM challenges that KIBS SMEs face. These challenges were analysed with specific reference to the key KM processes, i.e.: knowledge acquisition, knowledge documentation and storage, knowledge sharing, knowledge application, and knowledge protection. The research is a multiple-case study based on interviews to key informants of 23 Italian and Polish KIBS SMEs of different sectors. The analysis made it possible to find recurring issues and highlight differences. The study provides food for thought for researchers and practitioners willing to clarify what KM processes need proper solutions for the effective management of knowledge in small KIBS.

  • Knowledge management implementation in small and micro KIBS : A categorization
    • Ettore Bolisani
    • Enrico Scarso
    • Riccardo Ceccato
    • Małgorzata Zięba
    2023 Pełny tekst Knowledge and Process Management

    he main goal of the paper is to provide a statistical categorization of small and micro knowledge-intensive business service (KIBS) companies, based on their knowledge management (KM) attitude. Since knowledge is the main production factor and output of these companies, it is essential to achieve a better understanding of how they manage this resource. A questionnaire-based survey was conducted on a sample of Polish small and micro KIBS operating in various service sectors. A cluster analysis of the data was performed, to categorize the sample according to the KM attitude of the companies. Three main groups of companies were identified, varying in terms of their levels of “knowledge needs”, “intensity of use” of KM practices and “perceived barriers to KM implementation”. This classification is shown to characterize attitudes towards KM to a higher level of statistical significance than do structural characteristics. The survey was based on a single country sample. On the one hand, this provides consistency to the analysis. On the other hand, further insights can be obtained by a multi-national study. In addition, cluster analysis is exploratory in nature. The results provide useful insights for policy makers (to formulate policies for facilitating KM implementation in small KIBS) and managers (to reflect on the KM attitudes of their company). The statistical categorization of small and micro KIBS in terms of their KM attitude has been very rarely undertaken. Even the most recent investigations of KM issues used samples from large companies.

  • Knowledge Risks Arising from Digitalization
    • Małgorzata Zięba
    • Susanne Durst
    • Martyna Gonsiorowska
    2023 Pełny tekst

    Purpose - This conceptual paper aims to identify and analyse knowledge risks resulting from digitalization. Additionally, the paper tries to present factors influencing knowledge risks arising from digitalization and ways of handling them. Design/methodology/approach – The study is a continuation of the research by Durst and Zieba (2019) related to knowledge risks and their potential outcomes. This present study makes an update on the literature on knowledge risks arising from digitalization. Originality/value – The paper offers new insights for researchers dealing with the topic of knowledge risks in the context of digitalization and ways of handling them. Practical implications – The study provides insight for each of us, as the issue addressed concerns us all. By becoming aware of the potential consequences of such knowledge risks, people may meet and cope with digitalization in a better, more enlightened way. Limitations – The presented paper is based on prior literature and the authors’ reflections, experience, and analysis. Thus, to check for the suitability of the risks proposed, there is a need for empirical studies. Such studies are planned by the authors in the near future.

  • Knowledge-Based Expedited Parameter Tuning of Microwave Passives by Means of Design Requirement Management and Variable-Resolution EM Simulations
    • Sławomir Kozieł
    • Anna Pietrenko-Dąbrowska
    • Ali Raef
    2023 Pełny tekst Scientific Reports

    The importance of numerical optimization techniques has been continually growing in the design of microwave components over the recent years. Although reasonable initial designs can be obtained using circuit theory tools, precise parameter tuning is still necessary to account for effects such as electromagnetic (EM) cross coupling or radiation losses. EM-driven design closure is most often realized using gradient-based procedures, which are generally reliable as long as the initial design is sufficiently close to the optimum one. Otherwise, the search process may end up in a local optimum that is of insufficient quality. Furthermore, simulation-based optimization incurs considerable computational expenses, which are often impractically high. This paper proposes a novel parameter tuning procedure, combining a recently reported design specification management scheme, and variable-resolution EM models. The former allows for iteration-based automated modification of the design goals to make them accessible in every step of the search process, thereby improving its immunity to poor starting points. The knowledge-based procedure for the adjustment of the simulation model fidelity is based on the convergence status of the algorithm and discrepancy between the current and the original performance specifications. Due to using lower-resolution EM simulations in early phase of the optimization run, considerable CPU savings can be achieved, which are up to 60 percent over the gradient-based search employing design specifications management and numerical derivatives. Meanwhile, as demonstrated using three microstrip circuits, the computational speedup is obtained without design quality degradation.

  • Kod fontannowy z przyrastającą liczbą symboli źródłowych
    • Kamila Haustein
    • Marek Blok
    2023 Pełny tekst Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

    Kody fontannowe zabezpieczające transmisję przed wymazaniami wyróżnia brak określonej z góry długości i losowy sposób generacji kolejnych pakietów kodowych. W pracy pokazano jak właściwości tych kodów zależą od rozkładu macierzy generującej dla dwóch wariantów dostarczania pakietów do kodera. Szczególnie interesujący jest przypadek, gdy pakiety źródłowe trafiają do kodera stopniowo podczas transmisji. Uzyskane wyniki wskazują na możliwość realizacji transmisji strumieniowej o ograniczonej złożoności i wymaganiach pamięciowych dekodera.

  • Kolorowe Podcieniowe. Autorskie warsztaty architektoniczne. Projekt Narodowego Programu Rozwoju Czytelnictwa: Kierunek Kulturalne Żuławy
    • Marta Koperska-Kośmicka
    2023

    Warsztaty dla dzieci pt. „Kolorowe podcieniowe” mają na celu przybliżyć najmłodszym tradycyjne budownictwo okolic Gdańska – Żuław Wiślanych. W projekcie uczestniczyli uczniowie klas IV Szkoły Podstawowej w Wiślinie. Na warsztatach dzieci dowiedziały się co to jest krajobraz, jak wyglądały kiedyś domy na wsi, z czego je budowano i kto w nich mieszkał. Podczas spotkania zbudowały z dostarczonych materiałów (sklejka wycięta cyfrowo) model domu podcieniowego. Treść zajęć oparta zostanie na informacjach zawartych w książce dla dzieci, stworzonej przez autorkę projektu, pt. „Raptularz Żuławski czyli sekretny dziennik poszukiwacza skarbów” (2019).

  • Kolorowe Wiatrakowe. Autorskie warsztaty architektoniczne
    • Marta Koperska-Kośmicka
    2023

    Warsztaty dla dzieci pt. „Kolorowe wiatrakowe” mają na celu przybliżyć najmłodszym tradycyjne budownictwo okolic Gdańska – Żuław Wiślanych. Są drugą częścią cyklu opartego na autorskiej publikacji dla dzieci: Raptularz Żuławski czyli sekretny dziennik poszukiwacza skarbów (2019). Zostały zorganizowane we współpracy z Izbą Architektów RP o. Gdańsk. W trakcie warsztatów omówione zostały elementy krajobrazu kulturowego Żuław Wiślanych i najważniejsze zabytki drewnianej architektury delty Wisły. Główną częścią warsztatów jest wykonanie modelu wiatraka koźlaka. Warsztaty miały miejsce 18 listopada 2023, liczba uczestników 80 osób (40 dzieci wraz z rodzicami).

  • Kompetencje przyszłości – metody i wyzwania analizy
    • Łukasz Sienkiewicz
    2023

    Analiza przyszłych potrzeb kompetencyjnych – na poziomie gospodarek (gospodarki globalnej oraz krajowych), sektorów i zawodów oraz poszczególnych przedsiębiorstw – jest warunkiem prawidłowego funkcjonowania rynków pracy obecnie i w przyszłości. Wpływa także na funkcjonowanie samych podmiotów rynkowych (przedsiębiorstw, instytucji edukacyjnych i innych organizacji rynku pracy). Znajomość oczekiwań kompetencyjnych jest bowiem determinantą właściwego dopasowania na poziomie poszczególnych firm i stanowisk pracy (dopasowanie człowiek–-praca oraz człowiek–-organizacja). Jest także niezbędnym warunkiem skutecznej koordynacji rynku pracy oraz systemu edukacji. Samoistne dopasowanie kompetencji na rynku pracy występuje rzadko, gdyż jest bowiem ograniczane przez wieleszereg barier, a szczególnie barierę informacyjną (wynikającą z asymetrii informacyjnej pomiędzy uczestnikami rynku pracy). Dopasowanie nie ma charakteru statycznego – jest dynamiczne i zmienne w czasie – ponieważ zmieniają się oczekiwania względem kompetencji obecnych i przyszłych pracowników. Wpływają na to mają zmiany technologiczne, społeczne, ekonomiczne oraz ekologiczne, kształtujące popyt na pracę (oraz wymagane do jej wykonywania kompetencje), zmieniające modele biznesowe przedsiębiorstw, czy sposób dostarczania usług przez podmioty publiczne (digitalizacja). Nie wystarczy więc najdoskonalsze nawet badanie o charakterze statycznym – obrazujące stan potrzeb kompetencyjnych w danym momencie. Konieczne jest również badanie kompetencji w ujęciu przyszłościowym. Zdolność do identyfikacji przyszłych oczekiwań kompetencyjnych podmiotów na rynku pracy, staje się więc kluczowym czynnikiem pozwalającym na uniknięcie istotnych zagrożeń związanych z niedopasowaniem umiejętności do potrzeb (np. bezrobocia technologicznego), ale także jest też warunkiem przyszłego rozwoju. Celem rozdziału jest przegląd badań dotyczących kompetencji przyszłości oraz analiza istniejących metod ich badania, z uwzględnieniem wyzwań związanych z ich zastosowaniem.

  • Komputerowo wspomagana analiza elastycznych siłowników elektrostatycznych dla potrzeb implementacji w systemach mechatroniki
    • Jacek Szkopek
    2023 Pełny tekst

    Przeprowadzone badania naukowe rozpoczęto od szczegółowej analizy układu mechatronicznego dłoni robotycznych, powstałych na przestrzeni ostatnich 40 lat, w celu dokładnego rozpoznania ich głównych wymogów konstrukcyjnych i ograniczeń systemowych. Z uwagi na brak dostępnych narzędzi do symulacji omawianych siłowników, w rozprawie opracowano uniwersalne narzędzie – program do analizy numerycznej. U jego podstawy założono wykorzystanie programu Abaqus, funkcjonującego na bazie metody elementów skończonych MES, który następnie rozbudowano o własne skrypty implementujące siły elektrostatyczne na powierzchni rozpatrywanego modelu mięśnia. Tak przygotowany program umożliwił przeprowadzenie badań licznych modeli o różnych konfiguracjach geometrycznych. Uzyskane wyniki rozszerzają literaturę przedmiotu o zbiór charakterystyk napięciowo-mechanicznych i analizę rozkładu sił na elektrodach sztucznego mięśnia. Szczególną uwagę poświęcono zjawisku gwałtownego podciągnięcia siłownika po przekroczeniu pewnego napięcia/odkształcenia granicznego, charakterystycznego dla technologii mechanizmów elektrostatycznych. Wyniki obliczeń stanowią pierwszą znaną, a zarazem kompleksową i wyczerpującą analizę zagadnienia. Kolejnym podjętym w rozprawie wyzwaniem była budowa autorskich prototypów siłowników elektrostatycznych, która dzięki obszernym badaniom własnym metod łączenia polimerów i technologii elektrod, została zwieńczona sukcesem. Na podstawie przeprowadzonych testów zdecydowano wykorzystać selektywne napylanie próżniowe w celu nanoszenia przewodzących prąd powłok na powierzchnię izolatora. Łączenie poszczególnych warstw realizowano z użyciem zgrzewania laserowego, którego technologia została dokładnie przebadana i zaadaptowana do celów rozprawy. Tak powstałe jednostki napędowe poddane zostały obszernym testom mechanicznym, uwzględniającym ich charakterystyki mechaniczne i żywotność, jak również niezbędnym testom elektrycznym. W tym ostatnim przypadku, poza pomiarem rzeczywistych wartości rezystancji i pojemności elektrycznej wyznaczono charakterystyki napięciowe dla różnych geometrii sztucznych mięśni, sprawdzono zjawisko histerezy poszczególnych modeli oraz zweryfikowano odpowiedź siłowników na sygnały sterujące o różnych amplitudach i kształtach. Zebrane wyniki porównano do rezultatów otrzymanych z symulacji numerycznych oraz zestawiono z siłownikami innych zespołów badawczych, a także odniesiono je do zakresu funkcjonalności ludzkiej dłoni.

  • Konkurencyjność międzynarodowa kraju w świetle analizy krytycznej metodologii pomiaru Global Competitiveness Index
    • Hanna Adamkiewicz
    2023 Pełny tekst Przestrzeń Ekonomia Społeczeństwo

    W artykule zostały przedstawione wnioski z analizy krytycznej metodologii pomiaru Global Competitiveness Index, którą stosował do 2019 roku World Economic Forum (WEF). Przeprowadzone ba-dania autorskie umożliwiły również falsyfikację przyjmowanej przez WEF hipotezy, że konkurencyjność międzynarodowa determinuje poziom produktywności gospodarki. Wieloletnie badania dały asumpt do opracowania autorskiej propozycji podejścia do pomiaru poziomu konkurencyjności międzynarodowej kraju. Podstawowym celem niniejszego artykułu jest analiza porównawcza metodologii pomiaru poziomu konkurencyjności międzynarodowej, stosowanej przez WEF z proponowanym podejściem przez autorkę.

  • Kontrola procesowa za pomocą technik czujnikowych nowych metod selektywnego oczyszczania biogazu ze związków uciążliwych zapachowo
    • Edyta Słupek
    2023 Pełny tekst

    W obecnym czasie dużą uwagę zwraca się na opracowanie efektywnej technologii oczyszczania biogazu do gazu wysokometanowego. Głównym celem rozprawy doktorskiej było opracowanie ekonomicznie opłacalnych absorbentów do efektywnego oczyszczania strumieni biogazu z substancji uciążliwych zapachowo. Procesy absorpcji fizycznej prowadzono z wykorzystaniem zaprojektowanych i otrzymanych dotąd jeszcze nie publikowanych sorbentów na bazie cieczy głęboko eutektycznych (ang. Deep Eutectic Solvents, DES). Przeprowadzone badania wykazały konkurencyjność DES do obecnie stosowanych konwencjonalnych sorbentów. W przeprowadzonych badaniach wykazano także przydatność matryc czujnikowych do monitorowania procesów absorpcyjnego uzdatniania biogazu. Uzyskane wyniki stanowią kompleksową charakterystykę uzdatniania biogazu z lotnych związków odorotwórczych. Przedstawione cele cząstkowe zrealizowano i przedstawiono w ośmiu publikacjach naukowych, które stanowią podstawę niniejszej rozprawy doktorskiej.

  • Kościół franciszkanów Świętego Andrzeja Apostoła w Barczewie: badania i prace konserwatorskie w latach 2018-2023
    • Piotr Samól
    • Przemysław Gorek
    • Arkadiusz Koperkiewicz
    2023 Pełny tekst Warmińsko-Mazurski Biuletyn Konserwatorski

    Artykuł stanowi sprawozdanie z prac konserwatorskich prowadzonych w kościele franciszkańskim w Barczewie przez firmę Gorek Restauro wraz z odniesieniem do wynikow badań terenowych: architektonicznych, archeologicznych i konserwatorskich

  • Kościół św. Andrzeja w Barczewie. Historia przekształceń zespołu franciszkańskiego
    • Piotr Samól
    2023

    Kościół św. Andrzeja w Barczewie jest jedyną zachowaną świątynią klasztorną na Warmii, której początki sięgają średniowiecza. Porzucone przez franciszkanów w połowie XVI w. założenie klasztorne zostało odbudowane staraniem kardynała Andrzeja Batorego – bratanka króla Stefana i przekazane bernardynom. Batory zaczął wznosić także unikalną centralną kaplicę grobową, w której umieścił podwójny cenotaf dłuta Willema van den Blocke. Kolejne przebudowy kościoła i klasztoru zatarły jednak architekturę ówczesnego założenia. W książce autor śledzi losy założenia franciszkańskiego i chronologię jego przekształceń, poczynając od problematyki fundacji klasztorów na Warmii, a kończąc na omówieniu kompleksowych prac konserwatorskich prowadzonych w latach 2018-2022, w których brał udział. Ponieważ podstawowym źródłem do poznania dziejów zabytku jest jego autentyczna substancja, autor łączy warsztaty architekta i historyka – korzystając z wyników prowadzonych przez siebie badań terenowych i kwerend archiwalnych. Pracę uzupełnia próba analizy zmieniającej się w czasie architektury kościoła św. Andrzeja w ujęciu porównawczym. W efekcie książka znacząco poszerza wiedzę na temat budownictwa zakonnego w Prusach Królewskich oraz wskazuje, jak istotne są badania podstawowe (architektoniczne, archeologiczne, konserwatorskie, historyczne) zarówno dla poznawania dziejów poszczególnych obiektów, jak i prób syntezowania wiedzy o całych zjawiskach artystycznych.

  • Labour share and income inequalities in the European Union, taking into account the level of development of economies
    • Erik Soltis
    • Małgorzata Gawrycka
    • Szymczak Anna
    • Marta Kuc-Czarnecka
    2023 Pełny tekst EQUILIBRIUM Quarterly Journal of Economics and Economic Policy

    esearch background: The relationship between labour share and income inequality is a complex and multifaceted problem. Despite ongoing discussions among economists, there is still no consensus on the direction of the relationship between labour share and income ine-quality. Purpose of the article: The article aims to assess the impact of labour share on income inequal-ity, which is measured in three ways: the Gini index of gross income, the Gini index of market incomes, and the Gini index of household disposable income. Methods: Dynamic panel data models were applied to estimate the relationship between Gini coefficients and socio-economic indicators. The study investigated 25 European Union coun-tries over the 2011–2021 period. Findings & value added: Despite the long convergence process of the EU economies, there is still great diversity in the labour share, social inequalities, and the interplay between these factors. The added value of this research is the indication of labour share impact on three Gini measures covering a diverse income spectrum (from labour and capital). Based on the re-search findings, hypothesis 1, claiming that the more developed the national economy, the lower the share of employment income, favouring capital gains, is confirmed. Hypothesis 2 (as the share of income from work increases, the Gini coefficient of gross incomes decreases) must be rejected. There is no significant relationship between labour share and the studied Gini measures in 'old' EU countries. In 'new' EU members, there is a reverse relationship than assumed in hypothesis 2. The growth of the Gini coefficient was influenced by the rise in labour share, which can be attributed to the diversity in economic structures.

  • L’America di Mattei. Il Mattei degli americani
    • Luciano Segreto
    • Francesco Maccelli
    2023

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  • Lanthanide ions (Eu3+, Er3+, Pr3+) as luminescence and charge carrier centers in Sr2TiO4
    • Karol Szczodrowski
    • Mirosław Behrendt
    • J. Barzowska
    • N. Górecka
    • Natalia Majewska
    • Tadeusz Lesniewski
    • Marcin Łapiński
    • Sebastian Mahlik
    2023 DALTON TRANSACTIONS

    A series of strontium orthotitanate (Sr2TiO4) samples doped with 2% of a mole of europium, praseodymium, and erbium were obtained using the solid-state synthesis method. The X-ray diffraction (XRD) technique confirms the phase purity of all samples and the lack of the influence of dopants at a given concentration on the structure of materials. The optical properties indicate, in the case of Sr2TiO4:Eu3+, two independent emission (PL) and excitation (PLE) spectra attributed to the Eu3+ ions at sites with different symmetries: low – excited at 360 nm and high – excited at 325 nm, while, for Sr2TiO4:Er3+ and Sr2TiO4:Pr3+, the emission spectra do not depend on the excitation wavelength. The measurements of X-ray photoemission spectroscopy (XPS) indicate the presence of only one type of charge compensation mechanism, which is based on the creation of strontium vacancies Image ID:d2dt04177d-t1.gif in all cases. This suggests that the different charge compensation mechanisms cannot easily explain the presence of Eu3+ at two non-equivalent crystal sites. The photocurrent excitation (PCE) spectroscopy investigations, that have not been reported in the literature so far, show that among all the studied dopants, only Pr3+ can promote the electrons to the conduction band and give rise to electron conductivity. The results collected from the PLE and PCE spectra allowed us to find the location of the ground states of lanthanides(II)/(III) in the studied matrix.

  • Laser-Induced Graphitization of Polydopamine on Titania Nanotubes
    • Adrian Olejnik
    • Krzysztof Polaczek
    • Marek Szkodo
    • Alicja Stanisławska
    • Jacek Ryl
    • Katarzyna Siuzdak
    2023 Pełny tekst ACS Applied Materials & Interfaces

    Since the discovery of laser-induced graphite/graphene, there has been a notable surge of scientific interest in advancing diverse methodologies for their synthesis and applications. This study focuses on the utilization of a pulsed Nd:YAG laser to achieve graphitization of polydopamine (PDA) deposited on the surface of titania nanotubes. The partial graphitization is corroborated through Raman and XPS spectroscopies and supported by water contact angle, nanomechanical, and electrochemical measurements. Reactive molecular dynamics simulations confirm the possibility of graphitization in the nanosecond time scale with the evolution of NH3, H2O, and CO2 gases. A thorough exploration of the lasing parameter space (wavelength, pulse energy, and number of pulses) was conducted with the aim of improving either electrochemical activity or photocurrent generation. Whereas the 532 nm laser pulses interacted mostly with the PDA coating, the 365 nm pulses were absorbed by both PDA and the substrate nanotubes, leading to a higher graphitization degree. The majority of the photocurrent and quantum efficiency enhancement is observed in the visible light between 400 and 550 nm. The proposed composite is applied as a photoelectrochemical (PEC) sensor of serotonin in nanomolar concentrations. Because of the suppressed recombination and facilitated charge transfer caused by the laser graphitization, the proposed composite exhibits significantly enhanced PEC performance. In the sensing application, it showed superior sensitivity and a limit of detection competitive with nonprecious metal materials

  • Latent fingerprint imaging by spectroscopic optical coherence tomography
    • Marcin Strąkowski
    • Paulina Strąkowska
    • Jerzy Pluciński
    2023 OPTICS AND LASERS IN ENGINEERING

    Optical coherence tomography (OCT) is a non-contact and non-invasive optical method for evaluating semitransparent and scattering objects. Its unique features, such as non-destructive 3D measurements of tested objects with a fast scanning rate, make this technique interesting for latent fingerprint reading, which is the subject of this paper. So far, OCT has not found widespread use for reading fingerprints directly from surfaces due to its insufficient axial resolution. This problem has been overcome by applying spectroscopic analysis to the OCT measurements, which is based on retrieving the spatially resolved spectral characteristics of the recorded backscattered light directly from the OCT measurement data. The spectroscopic analysis is very sensitive to thin film thickness variations, improving the readability of the latent fingerprints by OCT, which is reported here as well. This study includes a description of spectroscopic analysis in combination with OCT and indicates the benefits for thin film evaluation, in particular, latent fingerprints. The example of latent fingerprint OCT measurements enhanced by spectroscopic analysis has been shown, as well as a brief discussion of the method’s applicability. Finally, improving fingerprint OCT imaging contrast and readability by applying spectroscopic analysis have been confirmed.

  • Leaf wettability and plant surface water storage for common wetland species of the Biebrza peatlands (northeast Poland)
    • Ewa Papierowska
    • Daria Sikorska
    • Sylwia Szporak-Wasilewska
    • Małgorzata Kleniewska
    • Tomasz Berezowski
    • Jarosław Chormański
    • Jan Szatyłowicz
    • Guillaume Debaene
    2023 Pełny tekst Journal of Hydrology and Hydromechanics

    Wetlands play a crucial role in buffering the effects of climate change. At the same time, they are one of the most endangered ecosystems on the globe. The knowledge of the water cycle and energy exchange is crucial for the practical preservation and exploiting their capabilities. Leaf wettability is an important parameter characterising the plant's ability to retain water on its surface, and is linked to the ecosystems' hydrological and ecological functioning. This research investigates the relationship between leaves' wettability based on contact angle measurements and water storage capacity (interception) for wetland vegetation. We performed the study for ten common plant species collected from Biebrza peatlands (Poland). We used CAM100 goniometer for the wetting contact angle measurements on the leaves' surface, and the weighing method for the plant surface water storage determination. The wetland plants' initial contact angle values ranged from 64.7° to 139.5° and 62.4° to 134.0° for the leaves' adaxial and abaxial parts, respectively. The average plant surface water storage was equal to 0.31 g·g–1, and values ranged from 0.09 to 0.76 g·g–1. The leaf hydrophobicity contributes to the amount of retained water. With increasing average contact angle, the amount of water retained on the plant decreased.

  • Leakage Current Measurements of Surge Arresters
    • Marek Olesz
    • Leszek Litzbarski
    • Grzegorz Redlarski
    2023 Pełny tekst ENERGIES

    The paper presents the methods of assessing the technical condition of varistor surge arresters used in laboratory tests and in operation—performed without disconnecting the arresters from the network. The analysis of the diagnostic methods was supplemented with the results of the measurements of the leakage current of arresters coming directly from their production and used in the power industry. Among the available methods of evaluating the technical condition of arresters, mainly indicator solutions (temperature and operation counter) and the measurement of the selected parameters of the leakage current are used. In the latter, the method of determining the resistive component of the leakage current, determined on the basis of the analysis of the voltage and current waveforms, or only the arrester current, has become widespread. In this type of measurement, current clamps are used in the operation, and additionally, in voltage measurements, voltage transformers are used, where you have to take into account the fundamental, additional sources of errors discussed in the article. These errors and the dispersion resulting from the production technology may fundamentally hinder the proper assessment of the technical condition; hence, it is so important to properly recognize the listed basic sources of measurement uncertainty. In addition, the analysis should take into account three factors related to external conditions: temperature, the voltage applied to the arrester, and the content of higher harmonics in the supply voltage, for which appropriate methods have been provided to determine the active component of the leakage current for reference conditions. This article presents the results of the measurements of the leakage currents of surge arresters measured with various methods.

  • LEVEL OF DETAIL CATEGORIZATION FOR THE APPLICATION IN URBAN DESIGN
    • Jan Cudzik
    • Barkin Güler,
    • Muhammed Aydoğan
    2023 Pełny tekst Przestrzeń i Forma

    Urban planning and urban design involve complex processes that require detailed information about the visual information of a place at various scales. Different graphic tools, such as game engines, are evolving to use urban representation fields. The concept of "level of detail" (LOD) has been used to categorize the level of detail in AEC applications such as BIM and GML for urban representation models. However, there is a need to distinguish between different LOD concepts commonly used in various fields, as these terms have different interpretations and implications. This article presents a novel approach to re-categorizing the level of detail concept in AEC applications, led by the traditional use of LOD and in parallel with urban planning scales. From an urbanist perspective, a four-stage LOD classification framework has been studied: LOD 1000 for urban and neighbourhood scales, LOD 2000 for the plaza and square scales, LOD 3000 for architectural and street scales, and LOD 4000 for protected and private areas.

  • Levels of creativity in architectural education
    • Karolina Życzkowska
    • Beata Krawczyk-Bryłka
    2023 Pełny tekst Global Journal of Engineering Education

    Architectural design combines engineering science and art, thus stimulating creativity is a challenge in the didactic process. There are various levels of creativity that can be attained through architectural education. From idea to architecture (FITA) is a teaching method based on metaphorical and analogical reasoning that was developed, implemented and tested during architectural design classes in the Faculty of Architecture at Gdańsk University of Technology. Gdańsk, Poland. Four components of the FITA method: predesign, design, research and communication, were examined. To evaluate the suitability of the method a p-survey and an e-survey were used. The p-survey was intended to investigate teachers’ and students’ preferences within architectural design studios and to indicate a penchant for designing based on the initial idea among both groups. The next survey was focused on the FITA assessment among students and their preferences for starting points of design, considering the students’ creativity level checked through the test for creative thinking - drawing production (TCT-DP). Findings indicate that the FITA method positively influences students’ creativity at many levels and allows them to see compositional analogies. The TCT-DP results show that this method is mostly beneficial for students with an average level of creativity.

  • Liczby Ramseya on-line dla różnych klas grafów
    • Renata Zakrzewska
    2023 Pełny tekst

    Rozpatrujemy grę rozgrywaną na nieskończonej liczbie wierzchołków, w której każda runda polega na wskazaniu krawędzi przez jednego gracza - Budowniczego oraz pokolorowaniu jej przez drugiego gracza - Malarkę na jeden z dwóch kolorów, czerwony lub niebieski. Celem Budowniczego jest zmuszenie Malarki do stworzenia monochromatycznej kopii wcześniej ustalonego grafu H w jak najmniejszej możliwej liczbie ruchów. Zakładamy, że gracze grają optymalnie czyli najlepiej jak można w danym momencie i nie popełniają błędów. Malarka będzie próbowała przeszkodzić Budowniczemu jak długo się tylko da. Taką grę będziemy nazywać ̃(H)-grą. W wersji asymetrycznej tej gry, Malarka unika czerwonej kopii grafu G oraz niebieskiej kopii grafu H. Taką grę będziemy nazywać ̃ (G, H)-grą. Wartością liczby Ramseya on-line ̃(H) - wersja symetryczna lub ̃(G, H) - wersja asymetryczna, jest to minimalna liczba tur, w której gra się zakończy. W rozprawie rozważamy liczby Ramseya on-line dla różnych klas grafów. Wyznaczamy wartości liczb Ramseya on-line ̃(P4, P10), ̃(P4, P11) oraz górne oszacowanie ̃(P4, Pn) dla 12 ≤ n ≤ 22. Ponadto przedstawiamy górne oszacowanie ̃(S3, Pl) dla l ≥ 3 oraz dokładną wartość ෩(S3, P5). Pokazujemy nowe oszacowania z dołu i góry dla liczb ̃(C3, Pk) oraz ̃(C4, Pk) dla odpowiednich k oraz wyznaczamy dokładną wartość ̃(C4, P9).

  • Light pollution from illuminated bridges as a potential barrier for migrating fish–Linking measurements with a proposal for a conceptual model
    • Catherine Perez Vega
    • Jechow Andreas
    • James A. Campbell
    • Karolina Zielińska-Dąbkowska
    • Franz Hölker
    2023 Pełny tekst BASIC AND APPLIED ECOLOGY

    Illuminated bridges have become important assets to navigable aquatic systems. However, if artificial light at night (ALAN) from illuminated bridges reaches aquatic habitats, such as rivers, it can threaten the river's natural heterogeneity and alter the behavioural responses of migratory fish. Here, via a pilot study, we quantified levels of ALAN at illuminated bridges that cross a river and, propose a conceptual model to estimate its potential implications on two migrating fish species with contrasting life histories. Night-time light measurements on the river Spree in Berlin were performed continuously along a transect and in detail at seven illuminated bridges. Photometric data of the pilot study showed rapidly increased and decreased light levels at several illuminated bridges from which we derived several model illumination scenarios. These illumination scenarios and their potential effect on migrating Atlantic salmon smolts (Salmo salar) and European silver eel (Anguilla anguilla) are presented as a conceptual model, considering illuminated bridges as behavioural barriers to fish migration. ALAN's adverse effects on freshwater habitats must be better researched, understood, managed, and properly communicated to develop future sustainable lighting practices and policies that preserve riverscapes and their biodiversity.

  • Linear viscoelastic transversely isotropic model based on the spectral decomposition of elasticity tensors
    • Maciej Lewandowski-Szewczyk
    • B. Grzeszykowski
    • M.d. Gajewski
    2023 INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES

    The linear viscoelasticity is still a useful model in the engineering for studying the behavior of materials loaded with different loading rates (frequencies). Certain types of materials reveal also an anisotropic behavior: fiber reinforced composites, asphalt concrete mixtures, or wood, to name a few. In general, researchers try to identify experimentally the dependence of engineering constants like: directional Young’s moduli and Poisson’s ratios on loading velocity by means of creep or harmonic oscillatory tests. This approach is appealing from the experimental point of view. However, from the modeling perspective, this is not the case. The engineering constants emerge in nonlinear manner in the relationship between the strain and stress via fourth order stiffness tensor components. This is especially true in higher order anisotropies, yet even in isotropy Poisson’s ratio appears nonlinearly in the stiffness tensor. Several models for the linear viscoelasticity of anisotropic materials already exist in the literature that try to tackle this issue. In this paper, we propose a linear viscoelasticity model for anisotropic materials based on the spectral decomposition of the stiffness tensor. The proposed model offers several advantages: the natural choice of the stiffness tensor eigenvalues as time-dependent variables, state variables with clear interpretation as creep strains, and reduced burden of storage utilizing the orthogonality of the eigenspaces. We implemented the model in the finite-element method system AceGen/AceFEM, and calibrated parameters of the model with the experimental data available in the literature, thus proving the adequacy of the proposed model to describe anisotropic viscoelastic materials.

  • Linking Fashion and Tourism: From Body to Clothing and Lifestyle
    • Nadzeya Sabatini
    • Lorenzo Cantoni
    2023

    There are many profound links between fashion and tourism. This chapter provides a critical reflection, mainly from a philosophical, historical, and linguistic perspective, on the dynamic relationship and parallel evolution between these two sectors. It explains how their intercon nectedness form and mirror contemporary society. This chapter classifies the connections between the two, starting with the person, her body, and the relationship the latter has with fashion and tourism, and with the contemporary society at large. Four layers of such connections are exemplified. It also discusses a selfie, as a symbolic (digital) communication object and a complex phenomenon facilitated by changing technological affordances and societal functions as an excellent case of the complex relationships between fashion and tourism.

  • Lipids and Food Quality
    • Izabela Sinkiewicz
    2023

    This chapter deals with lipids present in food as well as their chemical, biological, and functional properties. The chapter begins with a presentation of the main groups of lipids including their chemical structure and physical properties. The physical properties of lipids affecting food processing are covered. Then, the role of lipids in human nutrition is presented. This is followed by a description of the undesirable changes in food lipids during storage and processing. The next part provides a broad outline of the effect of fats on food quality. The role of lipids in the formation of rheological properties of food and their contribution to food discoloration are described and also presented as precursors of aroma compounds. The chapter further describes the chemical and biochemical reactions of lipids including hydrolysis, esterification, hydrogenation, and oxidation. Frying fats including frying media, deep frying, and nutritional and health aspects are also discussed. The chapter concludes by presenting the formation and stability of lipid emulsions. The chapter provides useful knowledge about fats and lipids for food technologists and consumers.

  • Lipopolysaccharides: regulated biosynthesis and structural diversity
    • Satish Raina
    2023 Pełny tekst INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES

    The cell envelope of Gram-negative bacteria contains two distinct membranes, an inner (IM) and an outer (OM) membrane, separated by the periplasm, a hydrophilic compartment that includes a thin layer of peptidoglycan. The most distinguishing feature of such bacteria is the presence of an asymmetric OM with phospholipids located in the inner leaflet and lipopolysaccharides (LPSs) facing the outer leaflet. The maintenance of this OM asymmetry is essential to impart a permeability barrier, which prevents the entry of bulky toxic molecules, such as antibiotics and bile salts, into the cells [1]. LPS is a complex glycolipid that, with few exceptions, is essential for bacterial viability and is one of the major virulence factors in pathogenic Gram-negative bacteria. Model bacteria, such as Escherichia coli, contain approximately 2–3 × 106 molecules of LPS that cover more than 75% of the OM [2]. The composition of LPS is highly heterogenous; however, they often share a common architecture, and for convenience can be divided into three parts. The first, a conserved glycophospholipid moiety called lipid A, which anchors LPS in the OM, constitutes the endotoxin principal since it is recognized by the innate immune cell receptor TLR4/MD2-CD14 complex. A proximal core oligosaccharide is attached to lipid A via 3-deoxy-α-D-manno-oct-2-ulsonic acid (Kdo), and in smooth bacteria a distal O-polysaccharide called an O-antigen is attached [3]. It should be noted that some bacteria display LPSs without the O-chain, which are thus named lipooligosaccharides (LOSs). The biosynthesis of LPS begins with the formation of the essential key precursor molecule Kdo2-lipid A, which requires the sequential action of seven essential enzymes on the cytoplasmic side of the IM. This Kdo2-lipid A serves as a substrate for an extension by the incorporation of various sugars by specific glycosyltransferases before the lipid A-core molecules are flipped by MsbA to the periplasmic side of the IM.

  • Load introduction to composite columns revisited—Significance of force allocation and shear connection stiffness
    • B. Grzeszykowski
    • Maciej Lewandowski-Szewczyk
    • M. Niedośpiał
    2023 Pełny tekst ENGINEERING STRUCTURES

    The AISC 360-16 Specification recommends that the design shear force between parts of a composite column in the load introduction area shall be calculated based on the force allocation at ultimate limit state. Applicability of this straightforward method to the load levels that usually arise in slender composite columns is questionable, as this capacity-based force allocation is only true when the axial force is equal to the plastic resistance of the composite cross-section. Next, the number of required shear connectors is calculated as a quotient of the design shear force and the strength of a single shear connector. We demonstrate that: first, for the lower load levels, the stiffness-based force allocation gives a more accurate estimate of the shear force; second, the number of shear connectors satisfying the strength requirement can lead to insufficient force transfer between parts of the composite cross-section. To investigate the shear transfer mechanism in composite columns, we derive an analytical model with linear elastic constitutive relations both for steel and concrete and three types of shear force slip laws: elastic, elastic plastic, and rigid plastic. The case studies carried out for different shear transfer scenarios demonstrate the importance of the shear connection stiffness on the effectiveness of the load introduction. The remaining portion of the shear force is transferred outside the load introduction area, which hampers the column's ability to withstand shearing from varying bending moments or incipient buckling. To control the shear force transfer efficiency by enhancing the shear connection stiffness, we propose an original Stiffness Method and provide design charts as an aid in the design process.

  • Longitudinal drug synergy assessment using convolutional neural network image-decoding of glioblastoma single-spheroid cultures
    • Anna Giczewska
    • Krzysztof Pastuszak
    • Megan Houweling
    • U Kulsoom Abdul
    • Noa Faaij
    • Laurine Wedekind
    • David Noske
    • Thomas Würdinger
    • Anna Supernat
    • Bart Westerman
    2023 Pełny tekst Neuro-Oncology Advances

    Abstract Background In recent years, drug combinations have become increasingly popular to improve therapeutic outcomes in various diseases, including difficult to cure cancers such as the brain cancer glioblastoma. Assessing the interaction between drugs over time is critical for predicting drug combination effectiveness and minimizing the risk of therapy resistance. However, as viability readouts of drug combination experiments are commonly performed as an endpoint where cells are lysed, longitudinal drug-interaction monitoring is currently only possible through combined endpoint assays. Methods We provide a method for massive parallel monitoring of drug interactions for 16 drug combinations in three glioblastoma models over a time frame of 18 days. In our assay, viabilities of single neurospheres are to be estimated based on image information taken at different time points. Neurosphere images taken at the final day (day 18) were matched to the respective viability measured by CellTiter-Glo 3D at the same day. This allowed to use machine learning to decode image information to viability values at day 18 as well as for the earlier time points (at day 8, 11, 15). Results Our study shows that neurosphere images allow to predict cell viability from extrapolated viabilities. This enables to assess the drug interactions in a time-window of 18 days. Our results show a clear and persistent synergistic interaction for several drug combinations over time. Conclusions Our method facilitates longitudinal drug-interaction assessment, providing new insights into the temporal-dynamic effects of drug combinations in 3D neurospheres which can help to identify more effective therapies against glioblastoma.

  • Long-term mortality after transcatheter aortic valve implantation for aortic stenosis in immunosuppression-treated patients: a propensity-matched multicentre retrospective registry-based analysis
    • Michał Walczewski
    • Aleksandra Gąsecka
    • Adam Witkowski
    • Maciej Dabrowski
    • Zenon Huczek
    • Radosław Wilimski
    • Andrzej Ochała
    • Radosław Parma
    • Bartosz Rymuza
    • Marek Grygier
    • Marek Jemielity
    • Anna Olasińska-Wiśniewska
    • Dariusz Jagielak
    • Radosław Targoński
    • Krzysztof Pastuszak
    • Peter Gresner
    • Marcin Grabowski
    • Janusz Kochman
    2023 Pełny tekst Postępy w Kardiologii Interwencyjnej

    Introduction Data regarding patients with a previous medical record of immunosuppression treatment who have undergone transcatheter aortic valve implantation (TAVI) are limited and extremely inconclusive. Available studies are mostly short term observations; thus there is a lack of evidence on efficacy and safety of TAVI in this specific group of patients. Aim To compare the in-hospital and long-term outcomes between patients with or without a medical history of immunosuppressive treatment undergoing TAVI for aortic valve stenosis (AS). Material and methods We conducted a retrospective registry-based analysis including patients undergoing TAVI for AS at 5 centres between January 2009 and August 2017. The primary endpoint was long-term all-cause mortality. Secondary endpoints comprised major vascular complications, life-threatening or disabling bleeding, stroke and new pacemaker implantation. Results Of 1451 consecutive patients who underwent TAVI, two propensity-matched groups including 25 patients with a history of immunosuppression and 75 patients without it were analysed. No differences between groups in all-cause mortality were found in a median follow-up time of 2.7 years following TAVI (p = 0.465; HR = 0.73; 95% CI: 0.30–1.77). The rate of major vascular complications (4.0% vs. 5.3%) was similar in the two groups (p = 1.000). There were no statistically significant differences in the composite endpoint combining life-threatening or disabling bleeding, major vascular complications, stroke and new pacemaker implantation (40.0% vs. 20.0%, p = 0.218). Conclusions Patients who had undergone TAVI for AS had similar long-term mortality regardless of whether they had a previous medical record of immunosuppression. Procedural complication rates were comparable between the groups.

  • Long‐time scale simulations of virus‐like particles from three human‐norovirus strains
    • Agnieszka Lipska
    • Adam Sieradzan
    • Cezary Czaplewski
    • Andrea D. Lipińska
    • Krzysztof Ocetkiewicz
    • Jerzy Proficz
    • Paweł Czarnul
    • Henryk Krawczyk
    • Józef Liwo
    2023 Pełny tekst JOURNAL OF COMPUTATIONAL CHEMISTRY

    The dynamics of the virus like particles (VLPs) corresponding to the GII.4 Houston, GII.2 SMV, and GI.1 Norwalk strains of human noroviruses (HuNoV) that cause gastroenteritis was investigated by means of long-time (about 30 μs in the laboratory timescale) molecular dynamics simulations with the coarse-grained UNRES force field. The main motion of VLP units turned out to be the bending at the junction between the P1 subdomain (that sits in the VLP shell) and the P2 subdomain (that protrudes outside) of the major VP1 protein, this resulting in a correlated wagging motion of the P2 subdomains with respect to the VLP surface. The fluctuations of the P2 subdomain were found to be more pronounced and the P2 domain made a greater angle with the normal to the VLP surface for the GII.2 strain, which could explain the inability of this strain to bind the histo-blood group antigens (HBGAs).

  • LOS and NLOS identification in real indoor environment using deep learning approach
    • Alicja Olejniczak
    • Olga Błaszkiewicz
    • Krzysztof Cwalina
    • Piotr Rajchowski
    • Jarosław Sadowski
    2023 Pełny tekst Digital Communications and Networks

    Visibility conditions between antennas, i.e. Line-of-Sight (LOS) and Non-Line-of-Sight (NLOS) can be crucial in the context of indoor localization, for which detecting the NLOS condition and further correcting constant position estimation errors or allocating resources can reduce the negative influence of multipath propagation on wireless communication and positioning. In this paper a deep learning (DL) model to classify LOS/NLOS condition while analyzing two Channel Impulse Response (CIR) parameters: Total Power (TP) [dBm] and First Path Power (FP) [dBm] is proposed. The experiments were conducted using DWM1000 DecaWave radio module based on measurements collected in a real indoor environment and the proposed architecture provides LOS/NLOS identification with an accuracy of more than 100% and 95% in static and dynamic senarios, respectively. The proposed model improves the classification rate by 2-5% compared to other machine learning (ML) methods proposed in the literature.

  • (Lost) Pride and Prejudice. Journalistic Identity Negotiation Versus the Automation of Content
    • Jan Kreft
    • Monika Boguszewicz-Kreft
    • Mariana Fydrych
    2023 Journalism Practice

    The objective of our research was to broaden the knowledge regarding the relationship between the work of journalists and their professional identity, and, in particular, to identify the attitudes of this professional group towards algorithmic content creation under conditions of liminality. Previously, the implementation of the technology of algorithmic content creation by media organisations was associated primarily with financial factors (production savings). The pandemic situation, for security reasons forcing the use of new technologies to perform remote work, became an additional factor enhancing the sense of liminality. A qualitative study was conducted in the form of 25 in-depth interviews in leading Polish media at the initial stage of the pandemic. The results showed that the most important aspect concerning liminality was the loss of pride in performing a prestigious profession. Following waves of financial savings in editorial offices, and after the pandemic, journalists viewed the algorithmic creation of content as the next potential “plague” affecting their perceived degradation of the profession. The anticipated change in working conditions, already interpreted as a threat to journalists, signified a liminal experience dictated by a new factor and prompted them to choose defence strategies.

  • Low-cost 3D Printed Circularly Polarized Lens Antenna for 5.9 GHz V2X Applications
    • Weronika Kalista
    • Luiza Leszkowska
    • Mateusz Rzymowski
    • Krzysztof Nyka
    • Łukasz Kulas
    2023

    This paper presents design and realization of a circularly polarized antenna consisting of a linearly polarized patch antenna and a 3D printed lens, at the same time performing the functions of wave collimator and a polarizer. The antenna is dedicated for 802.11p systems, as a part of road infrastructure, with operation bandwidth 5.85 - 5.925 GHz. Its realised gain and axial ratio at center frequency 5.9 GHz are 14.3 dBi and 2.17 dB respectively. The lens provides approximately 6% bandwidth with axial ratio below 3 dB. The proposed antenna is easy to design and fabricate and can be realized with the use of low-cost materials.

  • Low-Cost and Highly-Accurate Behavioral Modeling of Antenna Structures by Means of Knowledge-Based Domain-Constrained Deep Learning Surrogates
    • Sławomir Kozieł
    • Nurullah Calik
    • Peyman Mahouti
    • Mehmet Belen
    2023 IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION

    The awareness and practical benefits of behavioral modeling methods have been steadily growing in the antenna engineering community over the last decade or so. Undoubtedly, the most important advantage thereof is a possibility of a dramatic reduction of computational expenses associated with computer-aided design procedures, especially those relying on full-wave electromagnetic (EM) simulations. In particular, the employment of fast replacement models (surrogates) allows for repetitive evaluations of the antenna structure at negligible cost, thereby accelerating processes such as parametric optimization, multi-criterial design, or uncertainty quantification. Notwithstanding, a construction of reliable data-driven surrogates is seriously hindered by the curse of dimensionality and the need for covering broad ranges of geometry/material parameters, which is imperative from the perspective of design utility. A recently proposed constrained modeling approach with knowledge-based stochastic determination of the model domain addresses this issue to a large extent and has been demonstrated to enable quasi-global modeling capability while maintaining a low setup cost. This work introduces a novel technique that capitalizes on the domain confinement paradigm and incorporates deep-learning-based regression modeling to facilitate handling of highly-nonlinear antenna characteristics. The presented framework is demonstrated using three microstrip antennas and favorably compared to several state-of-the-art techniques. The predictive power of our models reaches remarkable two percent of a relative RMS error (averaged over the considered antenna structures), which is a significant improvement over all benchmark methods.

  • Low-Cost Behavioral Modeling of Antennas by Dimensionality Reduction and Domain Confinement
    • Sławomir Kozieł
    • Anna Pietrenko-Dąbrowska
    • Leifur Leifsson
    2023

    Behavioral modeling has been rising in importance in modern antenna design. It is primarily employed to diminish the computational cost of procedures involving massive full-wave electromagnetic (EM) simulations. Cheaper alternative offer surrogate models, yet, setting up data-driven surrogates is impeded by, among others, the curse of dimensionality. This article introduces a novel approach to reduced-cost surrogate modeling of antenna structures, which focuses the modeling process on design space regions containing high-quality designs, identified by randomized pre-screening. A supplementary dimensionality reduction is applied via the spectral analysis of the random observable set. The reduction process identifies the most important directions from the standpoint of geometry parameter correlations, and spans the domain along a small subset thereof. As demonstrated, domain confinement as outlined above permits a dramatic improvement of surrogate accuracy in comparison to the state-of-the-art modeling approaches.

  • Low-Cost Open-Hardware System for Measurements of Antenna Far-Field Characteristics in Non-Anechoic Environments
    • Jan Olencki
    • Vorya Waladi
    • Adrian Bekasiewicz
    2023 Pełny tekst

    Experimental validation belongs to the most important steps in the development of antenna structures. Measurements are normally performed in expensive, dedicated facilities such as anechoic chambers, or open-test sites. A high cost of their construction might not be justified when the main goal of antenna verification boils down to demonstration of the measurement procedure, or rough validation of the simulation models used for the development of the structure. Although solutions for far-field measurement of antennas in non-anechoic environments have been demonstrated in the literature, they utilize expensive equipment. In this work, a low-cost (around 3300 USD), system for experimental validation of antenna prototypes in non-anechoic conditions has been discussed. Its main components include the in-house developed heads and an open-hardware-based vector network analyzer. Performance of the system has been demonstrated using two antenna structures for which radiation patterns have been obtained. Comparisons against measurements performed in the anechoic chamber and using other expensive equipment have also been provided.

  • Low-frequency noise in Au-decorated graphene–Si Schottky barrier diode at selected ambient gases
    • Janusz Smulko
    • Katarzyna Drozdowska
    • Adil Rehman
    • Tesfalem Welearegay
    • Lars Österlund
    • Sergey Rumyantsev
    • Grzegorz Cywiński
    • Bartłomiej Stonio
    • Aleksandra Krajewska
    • Maciej Filipiak
    • Pavlo Sai
    2023 Pełny tekst APPLIED PHYSICS LETTERS

    We report results of the current–voltage characteristics and low-frequency noise in Au nanoparticle (AuNP)-decorated graphene–Si Schottky barrier diodes. Measurements were conducted in ambient air with addition of either of two organic vapors, tetrahydrofuran [(CH2)4O; THF] and chloroform (CHCl3), as also during yellow light illumination (592nm), close to the measured particle plasmon polariton frequency of the Au nanoparticle layer. We observed a shift of the DC characteristics at forward voltages (forward resistance region) when tetrahydrofuran vapor was admitted (in a Au-decorated graphene–Si Schottky diode), and a tiny shift under yellow irradiation when chloroform was added (in not decorated graphene–Si Schottky diode). Significantly larger difference in the low-frequency noise was observed for the two gases during yellow light irradiation, compared with no illumination. The noise intensity was suppressed by AuNPs when compared with noise in graphene–Si Schottky diode without an AuNP layer. We conclude that flicker noise generated in the investigated Audecorated Schottky diodes can be utilized for gas detection.

  • Low-frequency noise in ZrS3 van der Waals semiconductor nanoribbons
    • Adil Rehman
    • Grzegorz Cywiński
    • W. Knap
    • Janusz Smulko
    • Alexander Balandin
    • Sergey Rumyantsev
    2023 Pełny tekst APPLIED PHYSICS LETTERS

    We report the results of the investigation of low-frequency electronic noise in ZrS3 van der Waals semiconductor nanoribbons. The test structures were of the back-gated field-effect-transistor type with a normally off n-channel and an on-to-off ratio of up to four orders of magnitude. The current–voltage transfer characteristics revealed significant hysteresis owing to the presence of deep levels. The noise in ZrS3 nanoribbons had spectral density SI ~ 1/f^c (f is the frequency) with c ~ 1.3–1.4 within the whole range of the drain and gate bias voltages. We used light illumination to establish that the noise is due to generation–recombination, owing to the presence of deep levels, and determined the energies of the defects that act as the carrier trapping centers in ZrS3 nanoribbons.

  • Low-Voltage LDO Regulator Based on Native MOS Transistor with Improved PSR and Fast Response
    • Grzegorz Blakiewicz
    2023 Pełny tekst ENERGIES

    In this paper, a low-voltage low-dropout analog regulator (ALDO) based on a native n-channel MOS transistor is proposed. Application of the native transistor with the threshold voltage close to zero allows elimination of the charge pump in low-voltage regulators using the pass element in a common drain configuration. Such a native pass transistor configuration allows simplification of regulator design and improved performance, with supply voltages below 1 V, compared to commonly used regulators with p-channel MOS transistors. In the presented design of ALDO regulator in 180 nm CMOS X-FAB technology, an output voltage of 0.7 V was achieved with an output current of 10 mA and a supply voltage of 0.8 V. Simulation results show that despite the low supply voltage, output voltage spikes do not exceed 70 mV at the worst technology corner when output current transients from 100 uA to 10 mA. Under such conditions, stable operation and power supply rejection PSR = 35 dB were achieved with an output capacitance of 0–500 pF. The proposed regulator allows to push the limit of ALDO regulator applications to voltages below 1 V with only slight degradation of its performance.