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Repozytorium publikacji
Politechniki Gdańskiej

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  • Natural/bio-based sorbents as greener extractive materials for endocrine disrupting compounds in samples of different matrix composition
    • Justyna Płotka-Wasylka
    • Aneta Chabowska
    • Suwijak Pantanit
    • Opas Bunkoed
    • Michel Y. Fares
    • Muhammad Sajid
    • Dimitra Lambropoulou
    • Aleksandra Kurowska-Susdorf
    • Natalia Jatkowska
    2024 Pełny tekst TRAC-TRENDS IN ANALYTICAL CHEMISTRY

    Endocrine-disrupting compounds (EDCs) are a group of chemicals that interfere with the endocrine system, leading to adverse effects on human health and the environment. Increasing concerns over the EDCs presence in various environmental compartments has driven the search for greener extraction materials. Recently, the use of polymers of natural origin (biopolymers) has been demonstrated to be an effective and promising research direction due to their undeniable advantages over synthetic polymers. In this review, strategies for cellulose, chitin, and chitosan functionalization and their applicability for numerous microextraction techniques have been widely discussed. Following the trend related to the reuse of waste, various agricultural wastes that were employed for the isolation and enrichment of EDCs are described. The benefits and limitations of using natural sorbents have been highlighted.

  • Nauka w świecie cyfrowym okiem młodego inżyniera - mobilne aplikacje cross-platformowe
    • Roman Dykyj
    • Julian German
    • Przemysław Falkowski-Gilski
    2024 Pismo PG

    Istotnym punktem w analizie technologii mobilnych jest poznanie opinii osób z nimi zaznajomionych. W niniejszym artykule przedstawione zostaną wyniki badań dotyczących porównania technologii cross-platformowych (uniwersalnych) i natywnych (dedykowanych), w których uwzględniono opinie i doświadczenia deweloperów pracujących w obszarze technologii mobilnych. Badanie miało na celu zrozumienie preferencji, wyzwań i korzyści związanych z wyborem odpowiedniej technologii w kontekście tworzenia aplikacji mobilnych.

  • Nauka w świecie cyfrowym okiem młodego inżyniera - nawigacja mobilna w miastach
    • Joanna Piotrowska
    • Łukasz Potrykus
    • Jakub Olszewski
    • Daria Cygańska
    • Przemysław Falkowski-Gilski
    2024 Pismo PG

    Dynamiczny rozwój technologii ICT i miniaturyzacja komponentów elektronicznych doprowadziły do sytuacji, w której znaczna część światowego społeczeństwa korzysta z urządzeń mobilnych. Dzięki powszechnemu dostępowi do smartfonów każdy użytkownik może w prosty sposób sprawdzić swoje położenie, niezależnie od tego, gdzie w danej chwili się znajduje. Ponadto sami operatorzy sieci komórkowych oraz dostawcy szeregu serwisów korzystają z informacji opartych na systemach satelitarnych GNSS (Global Navigation Satellite Systems), aby monitorować i doskonalić jakość oferowanych usług.

  • Navigating the complexities of altruistic helping in Nonprofit Organizations: An analysis of Benefits, Burdens and managerial challenges
    • Joanna Szulc
    • Fabian Homberg
    2024 Public Management Review

    We investigate how individuals cope with side effects of altruistic behaviour at work, i.e. genuine helping behaviour which is not part of any job description, and what role the organizational context plays in these dynamics. Employing simultaneous dyadic interviews, we show how employees of non-profit organizations cope with undesired effects of altruistic help. Our data provides evidence of unintended outcomes for the individual which manifest in increased perceptions of emotional tension, problems with own work, and exploitation. We shed light on the involved mechanisms by analysing the psycho-emotional coping processes associated with helping behaviour. Implications for non-profit managers are discussed.

  • Navigating the Complexity: Understanding Social Integration in Smart Communities versus Smart Cities
    • Magdalena Ciesielska
    • Gabriela Viale-Pereira
    • Thomas J. Lampoltshammer
    2024

    This study delves into the differentiation between smart community and smart city concepts, employing a comprehensive review of conceptual literature. The aim of this study is to identify and deliberate on the nuanced disparities between these two paradigms. By establishing pivotal distinctions, we aim to scrutinize the integration of social aspects in the development and implementation of smart communities. Our findings will offer insights into the essential factors influencing individual and social behavioral changes, thereby facilitating the development of a conceptual model to guide future empirical investigations.

  • N-doped graphene quantum dot-decorated MOF-derived yolk-shell ZnO/NiO hybrids to boost lithium and sodium ion battery performance
    • Beata Bajorowicz
    • Monika Wilamowska-Zawłocka
    • Wojciech Lisowski
    • Andrzej Żak
    • Tomasz Klimczuk
    2024 APPLIED SURFACE SCIENCE

    Surface engineering at the nanoscale to obtain robust interface between metal oxides and quantum dots is essential for improving the performance and stability of battery materials. Herein, we designed and prepared novel N-doped graphene quantum dot-modified ZnO/NiO anode materials with a well-defined yolk-shell structure for lithium and sodium-ion batteries. NG QDs were assembled on the ZnO/NiO microspheres using three different coupling strategies: solvothermal, direct adsorption and annealing under N2 atmosphere. The presence of NG QDs deposited on the ZnO/NiO hybrids promoted enhanced electrical conductivity, lower chargetransfer resistance and provides more active sites. As a result, NG-ZnO/NiO_s anode obtained by solvothermal route exhibited high reversible delithiation capacity of 912 mAh/g at 18.6 mA g 1 and excellent cycling performance with the average delithiation capacity of 525 mAh/g at 372 mA g 1 over 400 cycles. Moreover, application of the NG-ZnO/NiO_s elecrode in Na-ion batteries revealed decent electrochemical behavior with capacity values reaching 235 mAh/g at 18.6 mA g 1. Importantly, surface properties, morphology and electrochemical behavior of obtained NG-ZnO/NiO hybrids were dependent on the combination route of NG QDs with ZnO/NiO microspheres indicating that quality of heterojunction between composite components has significant impact on the electrode performance.

  • Negative CO2 Emission Gas Power Plant As Technology for Utilization of Sewage Sludge, Production of Electrical Energy, and CO2 Capture - Case of Chamber Under Transpiration Cooling
    • Paweł Ziółkowski
    • Kamil Stasiak
    • Mario Ditaranto
    • Samuel Wiseman
    • Maja Kaszuba
    • Dariusz Mikielewicz
    2024

    This work focuses on the concept developed in the nCO2PP project, which aims to demonstrate a technology that allows to achieve negative CO2 emissions through Carbon Capture and Storage (CCS) applied to sewage sludge. A feedstock is first gasified, then the resulting syngas is burned in a semi-closed oxy-fuel gas turbine with pure oxygen and water, using the advantages of oxy-combustion, to ease the capture of CO2 in the resulting exhaust gases. High-temperature combustion later takes place in a dedicated wet combustion chamber before expansion in a turbine which produces electricity. Given that in Polish law sewage sludge is treated as biomass, a negative CO2 emission factor is achieved. Works in the project are performed both in experimental and design terms. The concept of transpiration cooling will be considered in terms of different methods. Additionally, previously unpublished computational flow dynamics (CFD) simulations related to transpiration cooling were compared with measurement and design analyses. Experimental efforts include a demonstration of water transpiration through a porous structure.

  • Network-assisted processing of advanced IoT applications: challenges and proof-of-concept application
    • Higinio Mora
    • Francisco A. Pujol
    • Tamai Ramírez
    • Antonio Jimeno-Morenilla
    • Julian Szymański
    2024 Pełny tekst Cluster Computing-The Journal of Networks Software Tools and Applications

    Recent advances in the area of the Internet of Things shows that devices are usually resource-constrained. To enable advanced applications on these devices, it is necessary to enhance their performance by leveraging external computing resources available in the network. This work presents a study of computational platforms to increase the performance of these devices based on the Mobile Cloud Computing (MCC) paradigm. The main contribution of this paper is to research the advantages and possibilities of architectures with multiple offloading options. To this end, a review of architectures that use a combination of the computing layers in the available infrastructure to perform this paradigm and outsource processing load is presented. In addition, a proof-of-concept application is introduced to demonstrate its realization along all the network layers. The results of the simulations confirm the high flexibility to offload numerous tasks using different layers and the ability to overcome unfavorable scenarios.

  • Neural network agents trained by declarative programming tutors
    • Jan Dobrosolski
    • Julian Szymański
    • Higinio Mora
    • Karol Draszawka
    2024

    This paper presents an experimental study on the development of a neural network-based agent, trained using data generated using declarative programming. The focus of the study is the application of various agents to solve the classic logic task – The Wumpus World. The paper evaluates the effectiveness of neural-based agents across different map configurations, offering a comparative analysis to underline the strengths and limitations of these approaches. We discuss the quantitative and qualitative aspects of these agents in scenarios that require generalization. For a concise comparison, we present the performance and resource utilization of different agents as follows: The Prolog- based agent showed a base task win rate of 61%, which dropped to 5% in a modified task setting, requiring 13KB of memory. The Q-Learning agent achieved a 2% win rate in the base task, with the modified task performance not applicable, and a memory requirement of 67KB. An agent based on a Convolutional Neural Network (CNN) recorded a 44% win rate on the base task and 32% on the modified task, consuming 134KB of memory. The Deep Q-Network (DQN) agent displayed a 56% win rate in the base task and 46% in the modified task, necessitating a substantial amount of memory, 284MB.

  • New concept of drilling auger for displacement pile installation
    • Adam Krasiński
    2024 Pełny tekst

    In 2020, a new version of the screw displacement auger for pile installation in soil was developed and patented in Poland. It was named DPDT (Displacement Pile Drilling Tool). The general aim of its development was to reduce the soil resistances to the auger during screwing into the ground while maintaning a good load-bearing capacity for the screw displacement piles. The “DPDT-Auger” prototype was tested as a scaled-down model in the laboratory as well as in full-scale in the field. Its efficiency was compared with an ordinary SDP auger in two ways: by assessing soil resistances during screwing into the ground and by assessing the bearing capacity of completed piles. This paper presents the field tests and their results. Over 80 piles were tested in six test sites. Among them, 24 piles were instrumented and subjected to static load tests. The test results were generally positive and showed that the DPDT auger generates less torque than the SDP auger but requires more rotations and a slightly longer pile installation time. When it comes to the bearing capacity of the compression load, both DPDT and SDP piles showed similar characteristics.

  • New heterometallic Co/Zn, Ag/Co, and Ag/Zn imidazolates: structural characterization and catalytic activity in the oxidation of organic compounds
    • Mattia Lopresti
    • Łukasz Kurowski
    • Luca Palin
    • Marco Milanesio
    • Magdalena Siedzielnik
    • Karolina Gutmańska
    • Adrianna Dobrenko
    • Tomasz Klimczuk
    • Ewelina Pawelczyk
    • Anna Dołęga
    2024 DALTON TRANSACTIONS

    Nanocrystalline powders of monometallic and bimetallic imidazolates of Co, Zn, and Ag were produced by a reaction carried out in water. The powders were characterized by powder X-ray diffraction and the crystal structures of new compounds Ag2ZnIm4 and Ag2CoIm4 (Im = imidazolate) were solved. Heterometallic Co/Zn imidazolates showed the standard ZIF-8 crystal structure while Ag/Zn and Ag/Co systems were isostructural with the copper analogs. The powders were further characterized by EDX, UV-Vis and FTIR ATR spectroscopy in solid state. The catalytic experiments indicated that out of the studied heterometallic compounds only Ag2Co(Im)4, exhibits some catalytic activity in the reaction of oxidation of 1-phenylethanol by tert-butylhydroperoxide at elevated temperature.

  • New skills for architects: 3D scanning for an immersive experience in architectural education
    • Szymon Kowalski
    • Jacek Lebiedź
    • Sandro Parinello
    • Francesca Picchio
    2024 Pełny tekst Global Journal of Engineering Education

    The authors of this article explore the integration of remote sensing techniques, specifically laser scanning and photogrammetry, as well as immersive visualisation via different methods applied to architectural design processes, and its potential impact on the professional development of future architects. The study demonstrates the value of extending the architectural design process into the interdisciplinary field of geomatics and computer science through mixed research methods, including interviews, hands-on activities, market observations and knowledge of technological advances. The study results suggest a growing demand for certain interdisciplinary skills among students, necessitating an expanded approach to architectural design education to take full advantage of technological advances. The observed new possibility of the emergence of new professional specialisations in architecture, such as digital inventory managers, highlights the need to adapt some educational pathways to meet the demands of the industry, especially in the context of architectural heritage. The implication of this approach is to recommend the integration of remote sensing techniques into architectural curricula to better prepare future architects for today’s ever-evolving practice.

  • New technologies for green hydrogen activation, storage, and transportation
    • Bráulio Barros
    • Natalia Łukasik
    • Joanna Kulesza
    • Jose Daniel da Silva Fonseca
    2024

    Developing new green hydrogen activation, storage, and transportation technologies is a highly complex and multidisciplinary endeavor. This challenge arises from integrating various scientific, engineering, and environmental considerations. Effective evaluation of green hydrogen technologies involves a holistic approach that considers not only the technical aspects but also economic, environmental, and social factors. These criteria help ensure that green hydrogen solutions contribute positively to sustainability and energy transition goals. This chapter aims to present the most recent and innovative approaches with respect to green hydrogen activation, storage, and transportation.

  • New trifunctional acrylic water-based paint with self-cleaning, biocidal and magnetic properties
    • Izabela Malinowska
    • Oliwia Paszkiewicz
    • Agata Markowska-Szczupak
    • Anna Zielińska-Jurek
    2024 Pełny tekst CERAMICS INTERNATIONAL

    In the present study, we report the synthesis and application of ZnFe2O4/SiO2-TiO2 nanocomposites with nonstoichiometric content of Fe to Zn used for the first time for the preparation of new generation trifunctional paints with self-cleaning, biocidal and magnetic properties. Currently, there are no compositions on the market for obtaining protective coatings in the form of paint, which simultaneously exhibit biocidal, magnetic and selfcleaning - photocatalytic properties. The effect of Zn:Fe content on the antimicrobial, magnetic and self-cleaning properties of obtained modified paints was investigated. Furthermore, the non-stoichiometric zinc ferrite in combination with TiO2 allowed to create of a surface that inhibits microorganisms’ growth. Self-cleaning properties were studied in the reaction of dye - neutral red degradation. The commercial white paint was not photocatalytic active. Paint modification with nanocomposites based on ZnO/ZnFe2O4 and TiO2 resulted in the effective degradation of natural red dye. The highest dye removal efficiency was observed for the sample containing ZnFe2O4/SiO2-TiO2 particles with a non-stoichiometric 1:2 (Fe: Zn) molar ratio. Trifunctional paints with photocatalytic, magnetic and biocidal properties are a novelty in building products. The composition can be applied to protective and decorative layers, giving magnetic, biocidal and self-cleaning properties.

  • News that Moves the Market: DSEX-News Dataset for Forecasting DSE Using BERT
    • Md. Nabil Rahman Khan
    • Md Rafiqul Islam
    • Cesar Sanin
    • Edward Szczerbicki
    2024

    Stock market is a complex and dynamic industry that has always presented challenges for stakeholders and investors due to its unpredictable nature. This unpredictability motivates the need for more accurate prediction models. Traditional prediction models have limitations in handling the dynamic nature of the stock market. Additionally, previous methods have used less relevant data, leading to suboptimal performance. This study proposes the use of Bidirectional Encoder Representations from Transformers (BERT), a pre-trained Large Language Model (LLM), to predict Dhaka Stock Exchange (DSE) market movements. We also introduce a new dataset designed specifically for this problem, capturing important characteristics and patterns that were missing in other datasets. We test our new dataset of headlines and stock market indexes on various machine learning techniques, including Decision Tree (DT), Logistic Regression (LR), K-Nearest Neighbors (KNN), Random Forest (RF), Linear Support Vector Machine (LSVM), Long Short-Term Memory (LSTM), Gated Recurrent Units (GRUs), Bidirectional Long Short-Term Memory (Bi-LSTM), BERT, Financial Bidirectional Encoder Representations from Transformers (FinBERT), and RoBERTa, which are compared to assess their predictive capabilities. Our proposed model achieves 99.83% accuracy on the training set and 99.78% accuracy on the test set, outperforming previous methods.

  • Nitrogen oxides removal from hydrogen flue gas using corona discharge in marine boilers: Application perspective
    • Dominik Kreft
    • Konrad Marszałkowski
    • Karol Szczodrowski
    2024 Pełny tekst INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

    This paper focuses on the combustion of hydrogen in boilers, as it appears to be a more effective method than using fuel cells for heating purposes due to higher boiler efficiency. One of the main disadvantages of hydrogen combustion in air is NOx formation. Therefore, the authors decided to introduce corona discharge as an inno- vative technique to clean hydrogen flue gas by effectively reducing NOx levels. The method involves generating positive plasma at atmospheric pressure by applying up to a 23 kV voltage difference between rod and ring- shaped electrodes. Experimental studies have shown that corona discharge can significantly lower the concen- trations of NO and NOx in exhaust gases. The maximum DeNOx level was found to be 32.3%, while the plasma generator uses 17.5% of the power contained in burned hydrogen. The findings suggest that this technology holds potential for application in industrial hydrogen combustion systems, offering an environmentally friendly alternative to conventional NOx reduction methods.

  • Nitrogen-incorporated boron-doped diamond films for enhanced electrochemical supercapacitor performance
    • Shradha Suman
    • Mateusz Ficek
    • Kamatchi J Sankaran
    • Jacek Ryl
    • Benadict Rakesh
    • Mukul Gupta
    • Ramasamy Sakthivel
    • Robert Bogdanowicz
    2024 ENERGY

    The electrochemical (EC) supercapacitor, known for its rapid charging, reliability, and versatile applications, demands optimized electrode characteristics and an understanding of their electrochemical behaviour. Although boron-doped diamond (BDD) holds promise as a supercapacitor electrode, a crucial gap exists in comprehending its material behaviour under specific growth conditions. Here, nitrogen-incorporated BDD (N-BDD) films with different microstructures are investigated. The morphology of N-BDD films is varied by tuning the substrate temperature (Ts) from 400 °C to 850 °C during the growth process. The diamond films grown at lower Ts = 400 °C consist of faceted grains, and the grain sizes shrink as Ts is increased (550 °C and 700 °C). Interestingly, the films grown at 850 °C (N-BDD850°C) show nanowire-like morphology with enhanced electrical conductivity. The spectroscopy and microscopy results reveal the concurrence of sp3-diamond and sp2-graphitic phases in the nanowire morphology. The EC supercapacitor studies disclose that formation of nanowire-like morphology for N-BDD850°C increases the active surface area and electron transport properties; hence, higher current response and enhanced specific capacitance (0.09 F cm−2 at a current density of 1.53 mA cm−2) are observed. Lifecycle stability of 82% is observed after 5000 cycles indicating the efficient performance of N-BDD850°C films.

  • Non-Adaptive Speed and Position Estimation of Doubly-Fed Induction Generator in Grid-Connected Operations
    • Marcin Morawiec
    • Krzysztof Blecharz
    2024 Pełny tekst IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS

    The nonadaptive speed and position estimation scheme for a doubly-fed induction generator (DFIG) is presented in this article. The observer structure is based on the extension of the mathematical model of DFIG to the introduced H vector. Based on the defined H vector, the nonadaptive position and speed estimation is proposed. The Lyapunov method is extended to the practical stability theorem to stabilize the structure. The classic stator field-oriented control to active and reactive power control is used in the sensorless control system. The performance of the proposed algorithm of the speed and position observer is validated by simulation and experimental results using the 2 kW generator. The comparison tests to the classical model reference adaptive system based observer are provided. Finally, the article contains a summary in which the non-adaptive speed estimation is discussed in context to the adaptive reconstruction of the rotor speed and position.

  • Noncentrosymmetric Triangular Magnet CaMnTeO6: Strong Quantum Fluctuations and Role of s0 versus s2 Electronic States in Competing Exchange Interactions
    • Xudong Huai
    • Emmanuel Acheampong
    • Erich Delles
    • Michał Winiarski
    • Maurice Sorolla II
    • Lila Nassar
    • Mingli Liang
    • Caleb Ramette
    • Huiwen Ji
    • Allen Scheie
    • Stuart Calder
    • Martin Mourigal
    • Thao Tran
    2024 Pełny tekst ADVANCED MATERIALS

    Noncentrosymmetric triangular magnets offer a unique platform for realizing strong quantum fluctuations. However, designing these quantum materials remains an open challenge attributable to a knowledge gap in the tunability of competing exchange interactions at the atomic level. Here, a new noncentrosymmetric triangular S = 3/2 magnet CaMnTeO6 is created based on careful chemical and physical considerations. The model material displays competing magnetic interactions and features nonlinear optical responses with the capability of generating coherent photons. The incommensurate magnetic ground state of CaMnTeO6 with an unusually large spin rotation angle of 127°(1) indicates that the anisotropic interlayer exchange is strong and competing with the isotropic interlayer Heisenberg interaction. The moment of 1.39(1) µB, extracted from low-temperature heat capacity and neutron diffraction measurements, is only 46% of the expected value of the static moment 3 µB. This reduction indicates the presence of strong quantum fluctuations in the half-integer spin S = 3/2 CaMnTeO6 magnet, which is rare. By comparing the spin-polarized band structure, chemical bonding, and physical properties of AMnTeO6 (A = Ca, Sr, Pb), how quantum-chemical interpretation can illuminate insights into the fundamentals of magnetic exchange interactions, providing a powerful tool for modulating spin dynamics with atomically precise control is demonstrated.

  • Nondestructive corrosion degradation assessment based on asymmetry of guided wave propagation field
    • Beata Zima
    • Emil Roch
    • Jochen Moll
    2024 ULTRASONICS

    The article presents the results of numerical and experimental investigation of guided wave propagation in steel plates subjected to corrosion degradation. The development of novel procedures allowing for the assessment of the corrosion degradation level is crucial in the effective diagnostics of offshore and ship structures that are especially subjected to aggressive environments. The study’s main aim is to investigate the influence of surface irregularities on wave propagation characteristics. The paper investigates wavefront asymmetry caused by the non-uniform thickness of damaged specimens. In the first step, the influence of thickness variability on the symmetry of the wave field has been investigated numerically. The corroded plates with variable degrees of degradation have been modeled using the random fields approach. The degree of degradation (DoD) varied from 0% to 40%. In the next step, the developed method was examined during experimental tests performed on specimens subjected to accelerated corrosion degradation. The experimental tests were conducted for intact and for corroded plates characterized by a DoD of 10%. It is demonstrated that the new approach based on wave field analysis can be used in structural state assessment.

  • Nondestructive global corrosion measurement using guided wavefield data
    • Beata Zima
    • Emil Roch
    2024 Pełny tekst MEASUREMENT

    Metallic structures often face degradation, and corrosion ranks among the most prevalent forms of deterioration. Accurate quantification of corrosion is crucial, especially for structures exposed to harsh environmental conditions, such as marine vessels and offshore installations. Because the traditional measurement methods based on scanning by ultrasonic gauge are time-consuming and provide only rough information on the thickness variability, there is a need to develop new robust and accurate diagnostics methods. This paper aims to investigate the corrosion monitoring of metal plates using guided wave propagation. Guided waves propagate within the entire volume of the specimen. If it is undamaged and isotropic, the velocity in all directions is the same, and the spreading wavefront takes a circular shape. The primary assumption presented in this paper is that the potential damage caused by corrosion leads to disturbance of this symmetry. The study shows Bilateral and Rotational Corrosion Symmetry Degree (BCSD and RCSD) functions, demonstrating a consistent decrease in symmetry values with increasing degree of degradation (DoD) caused by the corrosion process. The main aim of the study was to test the possibility of corrosion monitoring by using variable number of sensors comprising the transducer network. Also, the influence of the distance between the sensors affecting the size of the monitored area on the corrosion monitoring procedure was investigated. The paper contains the results of numerical and experimental campaigns conducted for corroded plates characterized by variable DoD and monitored using nine different transducers configurations. It is the first step in developing a novel measurement procedure specially designed for the ship and offshore industry. Therefore, because of the initial stage of the study, the last part of the paper discusses the limitations and drawbacks of the presented wave symmetry-based approach.

  • Non-invasive investigation of a submerged medieval harbour, a case study from Puck Lagoon
    • Łukasz Janowski
    • Andrzej Pydyn
    • Mateusz Popek
    • Paweł Tysiąc
    2024 Journal of Archaeological Science-Reports

    This study presents an innovative approach to underwater archaeological prospection using non-invasive methods of seabed exploration. The research focuses on the Puck medieval harbour, a cultural heritage site, and utilises acoustic and optical underwater remote-sensing technology. The primary objectives include optimising the use of Airborne Laser Bathymetry in underwater archaeology, enhancing the filtration process for mapping underwater sites, and utilising data from both multibeam echosounder and bathymetric LiDAR for detailed archaeological research. A systematic approach to data processing is advocated to maximise the value of collected data and inform subsequent investigations. The study demonstrates the high accuracy of bathymetric datasets from optical and acoustic sources, with an R-squared correlation coefficient of 0.9853. The application of these techniques is demonstrated, underscoring the compatibility and effective combination of these methods in underwater archaeological exploration. This research provides valuable insights and directions for future archaeological prospections based on active remote-sensing measurements.

  • NONSTRUCTURAL STIFFNESS ASSESSMENT IN INSTRUMENTED STEEL BUILDINGS
    • Tomasz Falborski
    • Amit Kanvinde
    2024

    Lateral stiffness of nonstructural components may significantly influence the initial stiffness of the entire structure and consequently alter its dynamic characteristics. While methods for simulating structural members are well-established, approaches for modeling nonstructural components that also participate in seismic response are notably less developed. In this paper a simplified, physically-intuitive approach for estimating the stiffness of nonstructural members based on vibration recordings of buildings is presented. The method comprises two components: (1) identifying the instants during the time history wherein components of interstory velocity are negligible, such that damping forces are zero, and (2) at these instants, using static analysis to estimate forces in the structural members by applying the recorded displacements to the entire structure, and the accelerations to all masses above the story of interest. The method derives from first-principles of dynamics and structural analysis, and is assessed against experimental data including shake table results on steel frames with nonstructural walls as well as quasi-static tests on the similar walls. The results are critically discussed in the context of their prospective applications in practical settings.

  • Normal stress distribution in built‑up cold‑formed column in relation to interconnecting bolt spacing
    • Patryk Deniziak
    • Elżbieta Urbańska-Galewska
    • Małgorzata Gordziej-Zagórowska
    2024 Pełny tekst Scientific Reports

    In order to increase a stiffness of cold-formed steel (CFS) elements it is practised to built-up the cross-section. In the analysed case, a main element is strengthened by adding extra chord in contact partially along the column. This additional chord acts as a longitudinal stiffener connected with the main section by series of bolts. Authors check whether rules applied over the years, for hot-rolled elements, can be indiscriminately used in the analysed CFS element. The aim of this study is to experimentally and computationally recognize the normal stress distribution in axially compressed CFS built-up column chords and to evaluate the element load-bearing capacity.

  • Novel Complementary Multiple Concentric Split Ring Resonator for Reliable Characterization of Dielectric Substrates with High Sensitivity
    • Tanveer Haq Ul
    • Sławomir Kozieł
    2024 IEEE SENSORS JOURNAL

    Accurate characterization of dielectric substrates with high sensitivity remains an important challenge in a variety of industrial applications. This paper proposes an innovative strategy to address this challenge by developing and optimizing a unique Complementary Multiple Concentric Split Ring Resonator (CMC-SRR). The major goal is to propose a sensor design with increased sensitivity and reliability for dielectric characterization. The CMC-SRR sensor uses simple complementary SRR structures and a 50 Ω microstrip transmission line to resonate at 17 GHz. To obtain optimal performance, a sensitivity analysis is performed, taking into account the structure's shape, size, thickness, and permittivity (MUT). Fabrication specifics include the use of an LPKF ProtoLaser on a 0.51-mm-thick Rogers 5880 substrate, which allows for more efficient and cost-effective manufacturing. An inverse regression model is created to forecast the permittivity of unknown materials using measured resonance frequencies and sample thickness. Our research yielded significant results, including a relative sensitivity greater than eight percent and a maximum permittivity prediction error of less than seven percent. These findings outperform current state-of-the-art complementary resonator-based sensors described in the literature.

  • Novel Complementary Resonator for Dielectric Characterization of Substrates Based on Permittivity and Thickness
    • Tanveer Haq Ul
    • Sławomir Kozieł
    2024 IEEE SENSORS JOURNAL

    This paper presents a novel complementary resonator featuring high sensitivity, low fabrication cost, and improved performance. The proposed structure consists of a complementary concentric square and circular ring resonator (CCSCRR) with multiple splits to enhance the inductance of the resonator. The proposed CCSCRR is coupled to a microstrip transmission line with an impedance of fifty ohms to create a high-sensitivity sensor. The lumped element equivalent circuit is employed to explain the sensor's operating principle. The geometric parameters of the CCSCRR are optimized to resonate at 15 GHz and the optimized sensor is fabricated on 0.762 mm thick dielectric substrate AD250 (εr = 2.5 ± 0.04). Dielectric materials with relative permittivity ranging from 2.5 to 10.2 and thickness from 0.508 mm to 1.905 mm are employed to investigate the properties of the proposed sensor and to carry out its calibration. Based on the measured resonant frequencies of the CCSCRR sensor when loaded with different materials under test (MUTs), an inverse regression model is constructed to predict the permittivity of the MUT. Comparisons with state-of-the-art microwave devices show that the proposed design is superior in terms of sensitivity, dielectric characterization reliability, and the applicability scope in terms of the MUT’s thickness and permittivity.

  • Novel fused pyran derivatives induce apoptosis and target cell cycle progression in anticancer efficacy against multiple cell lines.
    • K. Fabitha
    • Anoop Kallingal
    • Natalia Maciejewska
    • C. G. Arya
    • Munugala Chandrakanth
    • Neethu Mariam Thomas
    • Yupeng Li
    • Ramesh Gondru
    • Manne Munikumar
    • Janardhan Banothu
    2024 Pełny tekst NEW JOURNAL OF CHEMISTRY

    Nitrogen-based heterocycles such as pyrazole, imidazole, 1,2,4-triazole, benzimidazole, and benzotriazole substituted fused pyran derivatives (6a–e, 8a–e, 10a–e, 12a–e,&14a–e) have been synthesized and tested for their in vitro anticancer efficacies against MCF7, A549, and HCT116 cancer cell lines. Among the compounds, 6e, 14b, and 8c were identified as the most potent against MCF7, A549, and HCT116, with IC50 values of 12.46 2.72 mM, 0.23 0.12 mM, and 7.58 1.01 mM, respectively. Further studies demonstrated that these compounds can change cellular and nuclear morphology and inhibit colony formation in the tested cancer cells. They also remarkably block/inhibit the cell cycle progression of cancer cells at various phases. DNA damage analysis and apoptosis studies revealed that these compounds have the potential to induce DNA double-strand breaks and apoptosis. In silico absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties of the potent compounds were assessed, revealing that all the compounds exhibited favorable pharmacokinetic and toxicological properties. The potent compounds identified from this study can be considered as a lead for further drug design and development.

  • Novel materials and approaches for solid-phase (micro) extraction in LC-MS-based metabolomics
    • Michał Młynarczyk
    • Mariusz Belka
    • Weronika Hewelt-Belka
    2024 TRAC-TRENDS IN ANALYTICAL CHEMISTRY

    Metabolomics offers a unique approach to study biological systems. Liquid chromatography coupled to mass spectrometry serves as a powerful analytical tool to analyze complex mixtures of metabolites. However, successful metabolomic analysis relies on sample preparation. While untargeted analysis traditionally favors nonselective procedures like liquid-liquid extraction (LLE), these methods can compromise analytical performance due to limited analyte enrichment and potential matrix interferences. Solid-phase extraction (SPE) has emerged as a well-established and versatile technique for this purpose, offering advantages over other traditional methods like LLE. This review explores the applications of SPE and solid-phase microextraction (SPME) in LC-MS-based metabolomics. We discuss various modes of SPE, ranging from conventional flow-through cartridges and plates to approaches involving the dispersion of sorbent in a sample, as well as sorbents, their properties, and the diverse geometries of support materials employed in SPME. This review underscores the potential of emerging extraction protocols to further accelerate metabolomics research.

  • Novel monovalent and multivalent recombinant proteins of Borrelia burgdorferi sensu lato with potential diagnostic value – construction and biotechnological production
    • Weronika Grąźlewska
    2024 Pełny tekst

    The diverse antigenic structure of Borrelia burgdorferi sensu lato (s.l.) and the low degree of protein sequence conservation between genospecies causes many limitations in serodiagnosis of Lyme disease (LD). Using expression systems based on Escherichia coli, five monovalent B. burgdorferi s.l. recombinant proteins were produced. i.e., BB0108, BB0126, BB0298, BB0323, BB0689 (each in three variants derived from Borrelia afzelii, Borrelia burgdorferi sensu stricto, Borrelia garinii) and four multivalent chimeric proteins containing fragments of BmpA, BBK32 and BBA64 antigens. Data obtained from bioinformatic analysis of the amino acid sequence and linear epitope mapping with polypeptide array were used to design chimeric proteins. Subsequently, Western blot (WB) and ELISA determined the reactivity of the obtained antigens with specific anti-B. burgdorferi s.l. antibodies contained in human sera. The results indicate that BB0108 and BB0323 show moderate reactivity with specific IgG and IgM in WB and ELISA, regardless of the antigen variant used. At the same time, the obtained chimeric proteins showed high reactivity with IgG in WB. In addition, it has been shown that epitope mapping can be useful in the design of chimeric proteins that exhibit reactivity with a specific antibody isotype to increase the effectiveness of Lyme disease serodiagnosis.

  • Novel sorptive extraction techniques in bioanalysis evaluated by Blue Applicability Grade Index: The paradigm of fabric phase sorptive extraction and capsule phase microextraction
    • Natalia Manousi
    • Justyna Płotka-Wasylka
    • Victoria F. Samanidou
    2024 TRAC-TRENDS IN ANALYTICAL CHEMISTRY

    Fabric phase sorptive extraction (FPSE) and capsule phase microextraction (CPME) are two sol-gel derived microextraction techniques that emerged in the last decade towards the minimization of the environmental impact of conventional sample preparation approaches. Complementary to the well-established green metric tools, Blue Applicability Grade Index (BAGI) was recently proposed for the evaluation of method’s practicability. In this frame, BAGI evaluates the main characteristics of the sample preparation and analytical method (i.e., type of analysis, number of analytes, sample preparation, sample volume, sample throughput and simultaneous sample preparation, reagents and materials, instrumentation and automation degree, the fitness for purpose, and the automation degree) which revolve around the practical aspects of White Analytical Chemistry. The new index could easily identify the weak and strong points of each protocol for the successful evaluation of their practicality. In this article, BAGI was applied for the evaluation of different FPSE and CPME methods used in bioanalysis, proving their applicability.

  • Nowe zasady projektowania infrastruktury tramwajowej
    • Jacek Szmagliński
    2024 Pełny tekst Inżynier Budownictwa

    Wprowadzone we wrześniu 2022 roku zmiany w zasadach projektowania dróg, zwieńczone nowym Rozporządzeniem Ministra Infrastruktury w sprawie przepisów techniczno-budowlanych dotyczących dróg publicznych spowodowały pojawienie się daleko idących konsekwencji w przypadku projektowania tras tramwajowych.

  • Numerical Analysis of Mice Carotid Arteries’ Response Emphasizing the Importance of Material Law Constants’ Validation
    • Bartosz Sobczyk
    • Jacek Chróścielewski
    • Krzysztof Wilde
    2024 Pełny tekst Applied Sciences-Basel

    In this paper, a detailed validation of the passive material properties of mice carotid arteries and constants of the Fung and Holzapfel hyperelastic material laws is conducted by means of static nonlinear FEM analyses. The response of the carotid arteries in an inflation test is studied here for the following mouse models: wild-type, mdx, sgcd−/−, Eln+/+, Eln+/−, Fbln5+/+, and Fbln5−/−. All FEM computations are conducted on models that have been preliminarily checked for their reliability. The results of the calculations, namely, the relation between the internal pressure and the artery outer diameter, are verified against experimental responses and the applicability of the laws is assessed. New sets of Holzapfel constitutive relation constants are proposed for Eln+/+ and Fbln5−/− mice. Finally, the problem of carotid artery buckling is also discussed. The buckling pressures of the arteries are predicted using FEM models and nonlinear static analyses. These values are compared with the reference experimental results, which allow for further validation of the constitutive relations. The research emphasizes that computations and numerical methods enable an accurate description of bioengineering processes and behaviors but only if the models used are appropriately validated.

  • Numerical Determination of the Load-Bearing Capacity of a Perforated Thin-Walled Beam in a Structural System with a Steel Grating
    • Arkadiusz Denisiewicz
    • Tomasz Socha
    • Krzysztof Kula
    • Wojciech Macek
    • Wojciech Błażejewski
    • Grzegorz Lesiuk
    2024 Pełny tekst Applied Sciences-Basel

    This article presents the results of numerical simulations of a structural system consisting of steel perforated thin-walled beams and a steel grating. The simulations were conducted using the finite element method. The analysis took into account physical and geometric nonlinearity as well as the contact between the steel grating and the beams. The main goal of the research was to develop load-bearing curves for the main beam in the span range of 3–6 m and to identify destruction patterns depending on the span of the structural system. For the purpose of validating the developed numerical model, laboratory tests were conducted on two structural systems with spans of 3 m and 6 m, as well as tests on the strength parameters of the material taken from the tested beams. The laboratory tests confirmed the correctness of the proposed numerical model, which allowed for the simulation of the behavior of the structural system in the full range of spans.

  • Numerical Modeling and Simulation of Vehicular Crashes into Three-Bar Metal Bridge Rail
    • Howie Fang
    • Christopher Jaus
    • Qian Wang
    • Emre Palta
    • Łukasz Pachocki
    • Dawid Bruski
    2024 Computation

    Advanced finite element (FE) modeling and simulations were performed on vehicular crashes into a three-bar metal bridge rail (TMBR). The FE models of a sedan, a pickup truck, and a TMBR section were adopted in the crash simulations subject to Manual for Assessing Safety Hardware (MASH) Test Level 2 (TL-2) and Test Level 3 (TL-3) requirements. The test vehicle models were first validated using full-scale physical crash tests conducted on a two-bar metal bridge using a sedan and a pickup truck with similar overall physical properties and sizes to their respective vehicles used in the simulations. The validated vehicular models were then used to evaluate the crash performance of the TMBR using MASH evaluation criteria for structural adequacy, occupant risk, and post-impact trajectory. The TMBR met all MASH TL-2 requirements but failed to meet the MASH TL-3 Criteria H and N requirements when impacted by the sedan. The TMBR was also evaluated under in-service conditions (behind a 1.52 m wide sidewalk) and impacted by the sedan under MASH TL-3 conditions. The simulation results showed that the TMBR behind a sidewalk met all safety requirements except for the occupant impact velocity in the longitudinal direction, which exceeded the MASH limit by 3.93%.

  • Numerical modeling of PFAS movement through the vadose zone: Influence of plant water uptake and soil organic carbon distribution
    • Barbara Biesek
    • Adam Szymkiewicz
    • Jirka Simunek
    • Anna Gumuła-Kawęcka
    • Beata Jaworska-Szulc
    2024 Pełny tekst SCIENCE OF THE TOTAL ENVIRONMENT

    In this study, we investigated the effects of soil organic carbon (SOC) distribution and water uptake by plant roots on PFAS movement in the vadose zone with a deep groundwater table under temperate, humid climate conditions. Two series of numerical simulations were performed with the HYDRUS computer code, representing the leaching of historical PFOS contamination and the infiltration of water contaminated with PFOA, respectively. We considered soil profiles with three distributions of SOC (no SOC, realistic SOC distribution decreasing with depth, and uniform SOC equal to the content measured in topsoil), three root distributions (bare soil, grassland, and forest), and three soil textures (sand, sandy loam, and loam). The SOC distribution had a profound impact on the velocity of PFOS movement. The apparent retardation factor for realistic SOC distribution was twice as large as for the scenario with no SOC and more than three times smaller than for the scenario with uniformly high SOC content. We also showed that the root distribution in soil profoundly impacts the simulations of PFAS migration through soil. Including the root zone significantly slows down the movement of PFAS, primarily due to increased evapotranspiration and reduced downward water flux. Another effect of water uptake by plant roots is an increase of PFAS concentrations in soil water (evapo-concentration). The evapo-concentration and the slowdown of PFAS movement due to root water uptake are more significant in fine-textured soils than in sand.

  • Numerical modelling of different airbag folding patterns and their influence on occupant responses in frontal vehicle impact
    • Łukasz Pachocki
    • Howie Fang
    2024 INTERNATIONAL JOURNAL OF CRASHWORTHINESS

    This paper presented a procedure for airbag folding for the application in occupant safety studies and analysed the influence of different airbag folding patterns on the occupant severity in frontal impact. Airbags were folded in two patterns: zig-zag and top-roll, using two folding techniques: Initial Metric Method and Explicit Folding. The explicit folding was found to be more expensive in terms of preparation time. However, this approach provided more control over the whole folding process. The Initial Metric Method was more robust, however, it’s hard to apply for complex folding patterns. Deployments of airbags were validated against experimental data of pendulum tests. Those airbag models were applied to 2006 Ford F250 pickup truck. This vehicle was used for simulations of frontal vehicle impact where the 50th male Hybrid III crash test dummy was an occupant. Results of this simulation were compared with an actual test with a similar vehicle, under the same impact conditions. Results showed the head and chest accelerations were lower for top-roll folded airbag cases, however neck normal forces were higher compared to zig-zag folded airbag. The internal pressure in the early stage of deployment was 33% higher for the top-roll folded airbags.

  • Numerical Test for Stability Evaluation of Analog Circuits
    • Tomasz Stefański
    • Piotr Kowalczyk
    • Jacek Gulgowski
    2024 Pełny tekst

    In this contribution, a new numerical test for the stability evaluation of analog circuits is presented. Usually, if an analog circuit is unstable then the roots of its characteristic equation are localized on the right half-plane of the Laplace s- plane. Because this region is unbounded, we employ the bilinear transformation to map it into the unit disc on the complex plane. Hence, the existence of any root inside the unit disc implies circuit instability. In our test, we employ the global roots and poles finding algorithm based on phase analysis to detect the roots of the characteristic equation inside the unit disc. Unlike other stability tests, our approach allows one to evaluate the stability of analog circuits and systems whose characteristic equations are not polynomials. In order to demonstrate its efficiency, generality and applicability, we analyze a memristor-based chaotic circuit whose stability depends on the value of the fractional-order parameter. The proposed test correctly detects the parameter ranges of either stability or instability for the considered analog circuit.

  • Observing its long-term effects on a short-term, multi-day evaluation of the effectiveness of hearing aid use
    • Piotr Szymański
    • Bożena Kostek
    2024

    The main objective of the research study was to develop a method for evaluating the effectiveness of hearing protection with hearing aids tailored to the needs and prevailing conditions in the acoustic environments where the elderly most often reside. The method was also intended to estimate the benefits of hearing aids and allow prediction of such an effect based on a short-term trial. It is noteworthy that a short-term evaluation of effectiveness is usually made 30-45 days after the first fitting of hearing aids. The present study evaluated data obtained only after seven days of hearing aid use. Also, modifying the proposed method included the possibility of including a set of sounds, allowing auditory familiarization with environmental situations.

  • Occurrence of specific pollutants in a mixture of sewage and rainwater from an urbanized area
    • Magdalena Gajewska
    • Karolina Fitobór
    • Wojciech Artichowicz
    • Rafał Ulańczyk
    • Małgorzata Kida
    • Katarzyna Kołecka
    2024 Scientific Reports

    Urban runoff appears to be a pathway for transferring new emerging pollutants from land-based sources to the aquatic environment. This paper aimed to identify and describe the groups of pollutants present in rainwater surface runoff as well as their mixture with wastewater in the combined sewer system from urbanized catchments and to determine the correlations between these pollutants. Four leading groups of new emerging pollutants have been identified that may be present in rainwater and municipal wastewater mixtures. The samples were tested for microplastics, phthalic acid esters, pesticides, and polycyclic aromatic hydrocarbons as well as basic parameters. The pilot site was Słupsk (northwestern Poland). We conducted nine sampling campaigns at three points. The results of the present study revealed that (i) polycyclic aromatic hydrocarbons were not present in the tested samples; (ii) the selected organochlorine pesticides were detected during one campaign in the dry season and therefore were not of critical importance; (iii) out of the 11 analyzed phthalic acid esters, five selected substances released from commonly used plastic products were present; and (iv) the number of microplastics contained in the tested samples ranged from 1,400 to 14,036 pcs/L and evenoccurred during pure rainfall.

  • OCENA FUNKCJONOWANIA PASÓW RUCHU DLA ROWERÓW – PRZYPADEK TRÓJMIASTA
    • Katarzyna Cholc
    • Joanna Wachnicka
    2024 Pełny tekst Transport Miejski i Regionalny

    Artykuł dotyczy analizy nagrań trzech wybranych odcinków skrzyżowań w Gdańsku, na których znajdują się pasy dla rowerów wyznaczone w ramach jezdni. Na podstawie ww. materiału filmowego została wykonana ocena organizacji i natężenia ruchu, zachowania rowerzystów i kierowców oraz analiza sytuacji konfliktowych. Na każdym z trzech poligonów badawczych zostały przeanalizowane zachowania rowerzystów w ich obrębie. Przedstawiono liczbę rowerzystów na skrzyżowaniach w przedziale godzinowym (od godz. 6.00 do godz. 20.00) w zależności od wybranej przez nich trasy, procentowy udział rowerzystów na wybranych trasach na skrzyżowaniu oraz procentowy udział rowerzystów na pasach rowerowych i poza jezdnią na skrzyżowaniu. Z przedstawionych wyników wywnioskowano, iż niewielu cyklistów skorzystało z dostępnych pasów rowerowych na analizowanych skrzyżowaniach. Znacząca ich liczba wybrała trasy biegnące po chodnikach znajdujących się w obrębie skrzyżowania. Następnie skupiono się na obserwacji interakcji pomiędzy rowerzystami a kierowcami na jezdni. Zostały opisane i zliczone sytuacje niebezpieczne, które powtarzały się najczęściej. Na wszystkich trzech skrzyżowaniach najczęsciej obserwowano najeżdżanie przez pojazdy na pasy rowerowe. Przestrzeń przeznaczona dla rowerzystów była naruszana, co mogłoby się skończyć kolizją. Obserwacje te doprowadziły do postawienia pytania: czy zastosowanie pasów rowerowych w takich miejscach ma sens i czy jest to rozwiązanie bezpieczne dla rowerzystów. Efektem ww. analizy jest stwierdzenie, że stosowanie pasów rowerowych na skrzyżowaniach z dużą liczbą pasów ruchu oraz trudną geometrią skrzyżowania nie jest odpowiednim rozwiązaniem.

  • Ocena stanu chemicznego i zagrożeń wód podziemnych oraz powierzchniowych w rejonie Zalewu Wślanego
    • Małgorzata Pruszkowska-Caceres
    • Patrick Barwinski
    • Jakub Bożejewicz
    • Szymon Grabowski
    • Jakub Kopanicki
    • Kacper Aleksandrowicz
    2024 Przegląd Geologiczny

    The purpose of the research was to examine how factors such as land use and land management affect the quality of groundwater and surface water. These studies were possible thanks to funding from the IDUB Technetium Talent Management Grants project titled “Assessment of Anthropogenic Threat to Groundwater and Surface Water in the Region of the Vistula Lagoon”. The research area included a section of the Vistula Spit, ¯u³awy Wielkie and the coastal waters of the Vistula Lagoon. Field studies were conducted during three field trips; 15 groundwater points and 35 surface water points were examined. During these studies parameters such as temperature, pH, electrical conductivity, and the content of nitrogen, nitrates, phosphates, and sulfates were measured. In the Żuławy area it was found that surface water and groundwater are under the direct influence of the Vistula Lagoon, causing their salinity increase. Locally, man-induced chemical changes are also visible. The inflow of nutrients from fertilization of agricultural fields and uncontrolled discharge of wastes into drainage canals have been observed. The local anthropogenic impact on the water environment was also found in the Vistula Spit area. It was caused by pollutions from tourist facilities.

  • On Accelerated Metaheuristic-Based Electromagnetic-Driven Design Optimization of Antenna Structures Using Response Features
    • Sławomir Kozieł
    • Anna Pietrenko-Dąbrowska
    • Bogdan Pankiewicz
    2024 Pełny tekst Electronics

    Development of present-day antenna systems is an intricate and multi-step process requiring, among others, meticulous tuning of designable (mainly geometry) parameters. Concerning the latter, the most reliable approach is rigorous numerical optimization, which tends to be re-source-intensive in terms of computing due to involving full-wave electromagnetic (EM) simu-lations. The cost-related issues are particularly pronounced whenever global optimization is necessary, typically carried out using nature-inspired algorithms. Although capable of escaping from local optima, population-based algorithms exhibit poor computational efficiency, to the extent of being hardly feasible when directly handling EM simulation models. A popular miti-gation approach provides the involvement of surrogate modeling techniques, facilitating the search process by replacing costly EM analyses with a fast metamodel. Yet, surrogate-assisted procedures feature complex implementations, and their range of applicability is limited in terms of design space dimensionality that can be efficiently handled. Rendering reliable surrogates is additionally encumbered by highly nonlinear antenna characteristics. This paper investigates potential benefits of employing problem-relevant knowledge in the form of response features into nature-inspired antenna optimization. As demonstrated in the recent literature, re-formulating the design task with the use of appropriately selected characteristics locations of the antenna responses permits flattening the functional landscape of the objective function lead-ing to faster convergence of optimization procedures. Here, we apply this concept to na-ture-inspired global optimization of multi-band antenna structures, and demonstrate its rele-vance, both in terms of accelerating the search process but also improving its reliability. The advantages of feature-based nature-inspired optimization are corroborated through comprehen-sive (based on three antenna structures) comparisons with population-based search involving conventional (e.g., minimax) design problem formulation.

  • On effective surface elastic moduli for microstructured strongly anisotropic coatings
    • Victor Eremeev
    • Giuseppe Rosi
    • Salah Naili
    2024 Pełny tekst INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE

    The determination of surface elastic moduli is discussed in the context of a recently proposed strongly anisotropic surface elasticity model. The aim of the model was to describe deformations of solids with thin elastic coatings associated with so-called hyperbolic metasurfaces. These metasurfaces can exhibit a quite unusual behaviour and concurrently a very promising wave propagation behaviour. In the model of strongly anisotropic surface elasticity, strain energy as a function of the first and second deformation gradients has been introduced in addition to the constitutive relations in the bulk. In order to obtain values of surface elastic moduli, we compare dispersion relations for anti-plane surface waves obtained using the two-dimensional (2D) model and three-dimensional (3D) straightforward calculations for microstructured coatings of finite thickness. We show that with derived effective surface moduli, the 2D model can correctly describe the wave propagation.

  • On mechanics of piezocomposite shell structures
    • Mohammad Malikan
    2024 Pełny tekst INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE

    This study presents an original and novel investigation into the mechanics of piezo-flexo-magneto-elastic nanocomposite doubly-curved shells (PFMDCSs) and the ability to detect the lower and higher levels of electro-magnetic fields. In this context, by utilizing the first-order shear deformation shell model, stresses and strains are acquired. By imposing Hamilton's principle and the von Kármán approach, the governing equations have been obtained. The intelligent shell model consists of size-dependent influences, viz., strain gradients. This will take place via Mindlin's strain gradient elasticity theory and the subsequent re-establishing of the mathematical framework by incorporating this concept. The strain gradient results in a flexoelectric/flexomagnetic effect. The converse effect of the magnetic field on the basis of a close circuit has been assumed. The developed bending equations have been transferred into the algebraic ones by substituting an analytical technique based on homogeneous immovable simple support for the four edges. The problem has been solved according to the Newton-Raphson iteration scheme, and transverse deflections have been computed. For researching the rightness and precision of the shell models together with the solution process, a comparison is prepared by the finite element method (FEM) results for simplified shells, and a good correlation has been observed. At last, by examining several factors governing the problem, the conditions under which the magnetic effects can be noticeable and dominant in doubly-curved shells have been sought. This study could serve as a benchmark reference for piezoceramic-DCSs, as the presented governing equations are original. The most interesting outcome of this research is that the electro-magnetic response of intelligent structures can be entirely geometry-dependent.

  • On Memory-Based Precise Calibration of Cost-Efficient NO2 Sensor Using Artificial Intelligence and Global Response Correction
    • Sławomir Kozieł
    • Anna Pietrenko-Dąbrowska
    • Marek Wójcikowski
    • Bogdan Pankiewicz
    2024 KNOWLEDGE-BASED SYSTEMS

    Nitrogen dioxide (NO2) is a prevalent air pollutant, particularly abundant in densely populated urban regions. Given its harmful impact on health and the environment, precise real-time monitoring of NO2 concentration is crucial, particularly for devising and executing risk mitigation strategies. However, achieving precise measurements of NO2 is challenging due to the need for expensive and cumbersome equipment. This has spurred the development of more affordable alternatives, although their reliability is often uncertain. The aim of this study is to present a new method for accurately calibrating low-cost NO2 sensors. Our approach utilizes artificial intelligence techniques, particularly neural networks (NNs) acting as surrogates, trained to forecast sensor correction coefficients. These predictions rely on environmental variables (temperature, humidity, etc.), data from additional nitrogen dioxide sensors, and a short series of previous NO2 readings from the main sensor, all serving as inputs for the NN metamodel. As shown, integrating short-time-scale previous measurements significantly improves the quality of the calibration process, further bolstered by global response correction. Similar enhancements are achieved by considering environmental parameter differentials. Our calibration approach has been validated using a custom-built, cost-efficient monitoring platform and reference data collected over five months from high-performance public stations in Gdansk, Poland. The results demonstrate outstanding correction quality, with a correlation coefficient close to 0.93 compared to the reference data and an RMSE below 2.8 µg/m3. This establishes the calibrated sensor as a practical and cost-effective alternative to expensive traditional NO2 monitoring stations.

  • On optimal tracking of rapidly varying telecommunication channels
    • Maciej Niedźwiecki
    • Artur Gańcza
    2024 IEEE TRANSACTIONS ON SIGNAL PROCESSING

    When parameters of mobile telecommunication channels change rapidly, classical adaptive filters, such as exponentially weighted least squares algorithms or gradient algorithms, fail to estimate them with sufficient accuracy. In cases like this, one can use identification methods based on explicit models of parameter changes such as the method of basis functions (BF). When prior knowledge about parameter changes is available the BF approach can be optimized. The paper presents and compares three locally optimized BF algorithms differing in computational requirements. It also demonstrates how the performance of the proposed algorithms can be enhanced in cases where prior knowledge depends on unknown and/or time-varying environmental factors.

  • On rotary inertia of microstuctured beams and variations thereof
    • Victor Eremeev
    • Isaac Elishakoff
    2024 Pełny tekst MECHANICS RESEARCH COMMUNICATIONS

    We discuss the classic rotary inertia notion and extend it for microstructured beams introducing new microinertia parameters as an additional dynamic response to microstructure changes. Slender structures made of beam- or platelet-lattice metamaterials may exhibit not only large translations and rotations but also general deformations of inner structure. Here we considered a few examples of beam-like structures and derive their inertia properties which include effective mass density, rotary inertia and microinertia. Extended dynamic characteristics related to enhanced kinematics may be crucial for description of origami-like structures or other beam-lattice metamaterials.

  • On the Business Analyst's Responsibilities in an Agile Software Project - A Multi-Method Study
    • Mateusz Kwiatkowski
    • Aleksander Jarzębowicz
    2024

    [Context] Agile methods are now used in the majority of software projects, but the definitions of such methods rarely include the role of a business analyst (BA). [Objective] This paper investigates the responsibilities assigned to BAs participating in agile software projects. [Method] We identified potential responsibilities through a systematic literature review (3 databases) and interviews with 6 practitioners. The most commonly mentioned responsibilities were further evaluated in a questionnaire survey study with 72 respondents. [Results] The combined findings from the SLR and interviews resulted in 89 unique responsibilities grouped into 7 areas. 49 of these were ranked according to the frequency with which they were assigned in the survey respondents' organizations. [Conclusions] Our findings show that BAs typically support Product Owners (rather than taking on that role) and focus on requirements engineering, business needs, and working closely with development teams.

  • On the Fenchel–Moreau conjugate of G-function and the second derivative of the modular in anisotropic Orlicz spaces
    • Jakub Maksymiuk
    2024 CALCULUS OF VARIATIONS AND PARTIAL DIFFERENTIAL EQUATIONS

    In this paper, we investigate the properties of the Fenchel–Moreau conjugate of G-function with respect to the coupling function c(x, A) = |A[x]2 |. We provide conditions that guarantee that the conjugate is also a G-function. We also show that if a G-function G is twice differentiable and its second derivative belongs to the Orlicz space generated by the Fenchel–Moreau conjugate of G then the modular generated by G is twice differentiable on the Orlicz space generated by G. We also investigate second-order differentiability of action functionals on anisotropic Orlicz–Sobolev spaces.

  • On the Possibility of Improving the Oxidation Resistance of High-Chromium Ferritic Stainless Steel Using Reactive Element Oxide Nanoparticles
    • Łukasz Mazur
    • Aleksander Gil
    • Bartosz Kamecki
    • Kamil Domaradzki
    • Maciej Bik
    • Patryk Zając
    • Dariusz Zientara
    • Sebastian Molin
    • Tomasz Brylewski
    2024 Pełny tekst METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE

    High-chromium ferritic steels are current the only viable candidates for cheap interconnect materials for application in high-temperature solid oxide fuel and electrolyzer cells (HT-SOFCs/SOECs). The durability and operating characteristics of interconnects manufactured using these materials may be improved significantly by applying a protective-conducting MoCo2O4 coating and depositing an intermediate layer consisting of nanoparticles of Gd2O3—a reactive element oxide—on the surface of the steel substrate. The study demonstrated that the conditions of the thermal treatment of this layered system determine the efficacy of the applied modification with the reactive element. The persistence of this effect was tested over 7000 hours of quasi-isothermal oxidation in air at 800 C.