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  • Explainable machine learning for diffraction patterns
    • Shahid Nawaz
    • Vahid Rahmani
    • David Pennicard
    • Shabarish Pala Ramakantha Setty
    • Barbara Klaudel
    • Heinz Graafsma
    2023 Pełny tekst Journal of Applied Crystallography

    Serial crystallography experiments at X-ray free-electron laser facilities produce massive amounts of data but only a fraction of these data are useful for downstream analysis. Thus, it is essential to differentiate between acceptable and unacceptable data, generally known as ‘hit’ and ‘miss’, respectively. Image classification methods from artificial intelligence, or more specifically convolutional neural networks (CNNs), classify the data into hit and miss categories in order to achieve data reduction. The quantitative performance established in previous work indicates that CNNs successfully classify serial crystallography data into desired categories [Ke, Brewster, Yu, Ushizima, Yang & Sauter (2018). J. Synchrotron Rad. 25, 655–670], but no qualitative evidence on the internal workings of these networks has been provided. For example, there are no visualization methods that highlight the features contributing to a specific prediction while classifying data in serial crystallography experiments. Therefore, existing deep learning methods, including CNNs classifying serial crystallography data, are like a ‘black box’. To this end, presented here is a qualitative study to unpack the internal workings of CNNs with the aim of visualizing information in the fundamental blocks of a standard network with serial crystallography data. The region(s) or part(s) of an image that mostly contribute to a hit or miss prediction are visualized.

  • Exploring Stock Traders’ Cognitive Biases: Research Design and Simulator Framework
    • Maciej Tkacz
    • Józef Żurada
    • Paweł Weichbroth
    2023

    Cognitive bias is a phenomenon that has been extensively studied in stock trading and many other fields. This paper presents a framework for a Mobile Stock Trading Simulator (MSTS) that facilitates automatic investment in stocks with minimal human influence, by investigating the behavioral patterns and cognitive errors of stock market investors. The paper aims to determine whether investors’ investment strategies can be improved by detecting investment threats and reducing investment errors based on investors’ transaction histories. To accomplish this, we built a stock exchange simulator and implemented a decision tree to classify cognitive biases into one of six categories. By incorporating the behavioral patterns and cognitive biases of stock market investors into the MSTS's architecture, and by implementing a decision tree and stock exchange simulator, we can minimize the impact of human influence on automatic investments.

  • Exploring synergistic effects in physical-chemical activation of Acorus calamus for water treatment solutions
    • Beata Barczak
    • Justyna Łuczak
    • Paweł Kazimierski
    • Ewa Klugmann-Radziemska
    • Gartzen Lopez
    • Katarzyna Januszewicz
    2023 JOURNAL OF ENVIRONMENTAL MANAGEMENT

    The research proposed a novel method of obtaining sorption material from readily available Acorus calamus bio- mass through a combination of physical and chemical activation processes. The material with the highest specific surface area (1652 m2 g−1) was obtained by physical activation with CO2, followed by chemical activation with KOH. Reversing the order of activation methods resulted in a lower specific surface area (1014 m2 g−1) of the car- bon sample. Chemical activation produced activated carbon with a surface area of 1066 m2 g−1-, while physical activation produced 390 m2 g−1. This confirms the synergistic effect of combining the two activation methods for biocarbon. It was observed that physical activation with CO2 generates a diverse range of pores, including meso- and macropores, while chemical activation induces the formation of micropores. In contrast, reversing the order of these processes leads to the degradation of the porous structure. The application of physical-chemical activa- tion with synergistic effects represents a significant advancement in producing high-quality activated biocarbon for various applications, such as wastewater treatment and energy storage. The combination of the two activa- tion methods resulted in a synergistic effect, leading to the production of carbon material of higher quality. Addi- tionally, the diversified pore sizes will enable the sorption of various pollutants in the aquatic environment and air pollutants, where gas particles are much smaller.

  • Exploring the influence of personal factors on physiological responses to mental imagery in sport
    • Dagmara Budnik-Przybylska
    • Paweł Syty
    • Maria Kaźmierczak
    • Marta Łabuda
    • Łukasz Doliński
    • Adrian Kastrau
    • Patryk Jasik
    • Jacek Przybylski
    • Selenia di Fronso
    • Maurizio Bertollo
    2023 Pełny tekst Scientific Reports

    Imagery is a well-known technique in mental training which improves performance efficiency and influences physiological arousal. One of the biomarkers indicating the amount of physiological arousal is skin conductance level (SCL). The aim of our study is to understand how individual differences in personality (e.g. neuroticism), general imagery and situational sport anxiety are linked to arousal measuring with SCL in situational imagery. Thirty participants aged between 14 and 42 years (M = 22.93; SD = 5.24), with sport experience ranging between 2 and 20 years (M = 10.15; SD = 4.75), took part in our study. Participants listened to each previously recorded script and then were asked to imagine the scene for a minute. During the task SCL was monitored using the Biofeedback Expert 2000. Machine learning predictive models based on artificial neural networks have been trained for prediction of physiological response, as a function of selected psychological tests. We found an association among neuroticism, prestart anxiety, and general tendency to use imagery with SCL. From a practical point of view our results may help athletes, coaches, and psychologists to be more aware of the role of individual differences in sport.

  • Exploring the interfacial effects at the ETL/perovskite boundary in the semitransparent perovskite solar cells
    • Jędrzej Szmytkowski
    • Yulia Galagan
    • Damian Głowienka
    2023 Pełny tekst SOLAR ENERGY

    The recent focus has been made on the perovskite solar cells (PSCs) with an inverted configuration, where substantial improvements have been already achieved. However, the p–i–n structure needs a buffer layer for most of the configurations to modify the work-function of a deposited electrode. Additionally and very importantly, such a layer can also serve as a protective film that improves a stability of solar cells. Here, we study the semitransparent inverted PSCs, which have been prepared with the SnO2 buffer layer deposited by a spin-coating method. The main goal was to understand the dominant loss mechanisms in the operation of PSCs. Four photovoltaic parameters (an open-circuit voltage, a short-circuit current, a fill factor and a power conversion efficiency) were measured for a wide range of the light intensity. Their analysis allowed us to identify the transportation and recombination effects using an electrical modeling based on the drift–diffusion model. In addition, it has been concluded that the solution processed PCBM layer might not fully cover the perovskite film. As a consequence, the band-bending effect can occur at the PCBM/perovskite interface, where PCBM plays a role of the Electron Transport Layer (ETL). Therefore, we theoretically investigated the influence of this interface phenomenon on four photovoltaic parameters and the ideality factor simulated as a function of the ETL interface defect density. The increasing of the ideality factor to a high value (above 4) observed for the band-bending level around 300 eV indicates inhomogeneity of the interface. The results of this study should help to better understand the dominant electrical losses in the semitransparent inverted PSCs with a buffer layer which should further help to improve the performance of such devices.

  • Exploring the landscape of automatic cerebral microbleed detection: A comprehensive review of algorithms, current trends, and future challenges
    • Maria Ferlin
    • Zuzanna Klawikowska
    • Michał Grochowski
    • Małgorzata Grzywińska
    • Edyta Szurowska
    2023 Pełny tekst EXPERT SYSTEMS WITH APPLICATIONS

    This paper provides the first review to date which gathers, describes, and assesses, to the best of our knowledge, all available publications on automating cerebral microbleed (CMB) detection. It provides insights into the current state of the art and highlights the challenges and opportunities in this topic. By incorporating the best practices identified in this review, we established guidelines for the development of CMB detection systems. We are confident that these guidelines can serve as a foundation for further research. CMB detection is a crucial but challenging task that can be laborious for radiologists. With the increasing popularity of magnetic resonance imaging (MRI), the ability to detect CMBs has improved, but there is still a need to automate this process to enhance its efficiency and accuracy. A high prevalence of CMBs is closely associated with cognitive dysfunction, diabetes, hypertension, an increased risk of stroke, and intracerebral hemorrhage. It is alarming to note that strokes, Alzheimer’s disease, and Diabetes mellitus have secured their position as the second, seventh, and ninth most common causes of death worldwide, respectively. Moreover, CMBs are sometimes found in association with other pathologies and indicate a range of pathological processes in the cerebral vessels. Thus, it is essential to enhance the quality of diagnostics to facilitate prompt identification and treatment of these potentially life-threatening conditions. In this paper, we aimed to systematize the existing knowledge and best practices in automatic CMB detection, from fundamental information about CMBs and MRI image data, through employed datasets and CMB detection and verification algorithms, to methods of result evaluation. This can serve as a starting point for future research and the development of a CMB detection system that is practically applicable in medicine, leading to enhanced patient treatment outcomes.

  • Exploring the Prevalence of Anti-patterns in the Application of Scrum in Software Development Organizations
    • Michał Wróbel
    • Dorota Przała
    • Paweł Weichbroth
    2023 Pełny tekst

    The paper presents a survey-based study that aimed to determine the prevalence of anti-patterns in the Scrum software development methodology. A total of 35 anti-patterns were selected from the literature review, and 42 respondents indicated whether they had encountered each anti-pattern in their organizations. The study found that``Unfinished Tasks'' was the most prevalent anti-pattern, highlighting the importance of proper planning and task management within sprints. Additionally, several other common anti-patterns were identified, including daily scrums being extended beyond the recommended time, user stories not being fully refined, and the sprint goal not being defined at the sprint planning meeting. The findings of this study provide valuable insights into the current state of Scrum methodology in software development organizations and highlight areas where there is room for improvement.

  • Exploring the relationship between investment choices, cognitive abilities risk attitudes and financial literacy
    • Muhammad Mushafiq
    2023 Journal of Economic and Administrative Sciences

    Purpose The main purpose of this study is to investigate the investment choices' relationship with cognitive abilities, risk aversion, risky investment intentions, subjective financial literacy and objective financial literacy. Design/methodology/approach To examine the relationship, two investment choices were given to 256 subjects from Pakistan. Questionnaire had total 20 questions for measuring five variables. To review this nexus, discriminant analysis was used as to explore the depth of the nexus that is the ability of the variables to predict the investment choices. Findings This study establishes the findings that Investment choices are guided by risk aversion, risky investment intentions, financial literacy (subjective and objective) and cognitive abilities. The risk aversion has negative relation to investment choices and other variables depict positive relationship to with investment choices. Practical implications This study provides a new and useful understanding into the existing literature on investment choices. The results are significant as the cognitive abilities show a positive contribution to the investment choices. This is point of significance as the portfolio managers and advisors would get help in regards of advising investments as they are aware what factors impact the investment choices. Originality/value This study is novel in its nature to evaluate investment choices using the cognitive ability alongside risk attitudes and financial literacy.

  • Exploring the Usability and User Experience of Social Media Apps through a Text Mining Approach
    • Anna Baj-Rogowska
    • Marcin Sikorski
    2023 Pełny tekst Engineering Management in Production and Services

    This study aims to evaluate the applicability of a text mining approach for extracting UUX-related issues from a dataset of user comments and not to evaluate the Instagram (IG) app. This study analyses textual data mined from reviews in English written by IG mobile application users. The article’s authors used text mining (based on the LDA algorithm) to identify the main UUX-related topics. Next, they mapped the identified topics with known theoretical constructs to place them in their nomological network relevant to the usability (the 5Es framework by Quesenbery) and UX (the Honeycomb model by Morville). Finally, to expand the study with an emotional diagnosis, sentiment analysis was performed on two levels: (i) for each recognised topic, and (ii) for the full dataset to uncover general insights into users’ emotions within all reviews. The case study of the IG app confirms the usefulness of user feedback data for software development and points out that the review data have the potential for the early detection of frustration and negative feelings introduced during the use of the application. Conducting conventional UUX evaluations with users is problematic since they are remotely located, and the user-generated content of a social app undergoes continuous and frequent changes. Thus, the consecutive stages of the proposed methodology, based on text mining algorithms, constitute a proposed framework for examining the user-perceived quality projection of applications from user feedback, and they are the main contribution of this article. The used approach can be valuable for helping developers, designers and researchers to reveal user problems and fulfil user satisfaction regarding UUX aspects for specific software features.

  • Export diversification and dependence on natural resources
    • Zuzanna Helena Zarach
    • Aleksandra Parteka
    2023 ECONOMIC MODELLING

    Low export diversification is a risk-augmenting factor for many countries dependent on natural resources. The literature tends to focus on the growth effects of resource dependence (‘resource curse’ debate) while not much is known on how it affects the variety of non-resource exports. To quantify this effect we decompose the relative Theil index using product-level export data from 160 countries over the time period 1996–2018. We reveal that most (above 70%) of low export diversification level is driven by the limited variety of products other than natural resources. At the same time, natural resource dependence (in particular on fossil fuels) correlates negatively with the diversification of the non-resource portion of the export basket, in particular of technologically advanced products. Econometric estimates with interaction terms and case studies of countries that managed to escape the resource trap show that institutional quality determines the ability of resource exporters to diversify.

  • Exposure scenario and risk assessment of infants and newborns to bisphenols and their derivatives from diapers
    • Aneta Chabowska
    • Natalia Jatkowska
    • Paweł Kubica
    • Justyna Płotka-Wasylka
    2023 Pełny tekst ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY

    Newborns and infants are more sensitive to harmful compounds such as bisphenols and their derivatives because of their not fully developed detoxification mechanism. Exposure to these substances can lead to developmental problems and health consequences in adulthood. Since disposable baby diapers are used from the first days of life and remain in contact with the baby skin, it seems important to monitor the levels of endocrine disrupting chemicals (EDCs) in such products. Ultrasound assisted solvent microextraction of porous membrane-packed solid sample (UASE-PMSS) was used in sample preparation. Liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) was used at determination step. Bisphenol A was quantified with the highest frequency at 81 % of samples tested, ranging from 5.0 to 520 ng/g. BADGE⋅2HCl was also quantified in high concentrations (from 6.8 to 530 ng/g), but was found in only 15 % of the tested samples. The daily exposure dose (DED) of bisphenols was calculated. In addition health risk assessment was conducted using previous (4 μg/kg BW) and actual (0.2 ng/kg BW) values of tolerable daily intake (TDI) of bisphenol A recommended by European Food Safety Authority (EFSA).

  • Extraction and Analysis of Bisphenols and Their Derivatives in Infant and Toddler Ready-to-feed Meals by Ultrasound-assisted Membrane Extraction Followed by LC MS/MS
    • Natalia Jatkowska
    • Paweł Kubica
    2023 Pełny tekst JOURNAL OF FOOD COMPOSITION AND ANALYSIS

    This research developed an ultrasound-assisted membrane extraction coupled with liquid chromatography-tandem mass spectrometry method for the determination of nineteen bisphenols and their derivatives in infant and toddler ready-to-feed meals. The calibration curves for all analytes were linear in the tested range, and the limit of detection and limit of quantitation were in the range 0.27 to 0.79 ng/g and 0.80 to 2.4 ng/g, respectively. The recovery values were in the range of 76 to 138%. This method was successfully applied to determine the content of bisphenols in 56 real samples of ready-to-eat meals for infants and toddlers. All of the analytes were quantified in at least one sample in the range of 1.0-371.9 ng/g. Mean exposures to bisphenols were estimated to be 9.01-769.49 ng/kg bw/day for both female and male babies. The health risk assessment revealed hazard quotient < 1, indicating that consumption of ready-to-eat meals is unlikely to pose any health risks to babies, even at the highest concentrations found in this study.

  • Extractive detoxification of hydrolysates with simultaneous formation of deep eutectic solvents
    • Patrycja Makoś-Chełstowska
    • Edyta Słupek
    • Karolina Kucharska
    • Jacek Gębicki
    2023 Pełny tekst Chemical and Process Engineering : New Frontiers

    The hydrolysis of lignocellulosic biomass results in the production of so-called fermentation inhibitors, which reduce the efficiency of biohydrogen production. To increase the efficiency of hydrogen production, inhibitors should be removed from aqueous hydrolysate solutions before the fermentation process. This paper presents a new approach to the detoxification of hydrolysates with the simultaneous formation of in-situ deep eutectic solvents (DES). In the first stage of the study, inhibitors were identified in the real hydrolysate samples using high-performance liquid chromatography (HPLC). Four monoterpenes were tested for their potential to extract furfural (FF) with simultaneous DES formation. An optimization process of the most important parameters affecting the extraction process and DES formation (Thymol:FF) was conducted using the Central Composite Design (CCD) model. A temperature of 40 ◦C, pH of 7, mHBD : mHYD ratio of 2:1, and time of 50 min were selected as the optimal conditions. These results indicate the high efficiency of FF removal from hydrolysates (92.1–94.6%) in a one-step process. Meanwhile, the structural properties of the formed DES measured by Fourier-transform infrared spectroscopy (FT-IR) and Nuclear magnetic resonance spectroscopy (NMR) differed only slightly from those of the DES composed of pure substances (Furfural and Thymol).

  • Fabrication and Characterization of Green Polyurethane Foams with Enhanced Vibration Damping Capability
    • Paulina Parcheta-Szwindowska
    • Karina Kopczyńska
    • Martyna Kordyzon
    • Janusz Datta
    2023 Pełny tekst ACS Sustainable Chemistry & Engineering

    Over the past decades, there has been an intensive development of the technologies and innovations aimed at increasing the quality of life. This development largely concerns the comfort of use of everyday products that, among others, are products of the automotive, construction, or furniture industries. Considering the increase in the comfort of using products such as cars, houses, and flats, one of the comfort features of their use is the ability to dampen the sounds coming from the outside. Currently, in addition to wood based boards, mineral wool, or glass wool fillings, polyurethane foams are more often used as oundproofing materials. This article describes the method of obtaining selected mechanical and thermal properties in flexible polyurethane foams with the ability to dampen vibrations, which were obtained with the use of raw materials of natural origin. The results of the tests of thermal stability and the vibration damping coefficient confirmed the possibility of using flexible polyurethane foams of natural origin as an alternative to the previously used vibration damping materials in the construction or the automotive industry.

  • Fabrication of wormhole-like YSZ and Ni-YSZ by the novel soft-hard template CTAB/NaCl-assisted route. Suppressing Ni coalescence in SOFC
    • Patryk Błaszczak
    • Agata Ducka
    • Barbara Wolanin
    • Krzysztof Matlak
    • Grzegorz Machowski
    • Marta Prześniak-Welenc
    • Sea-Fue Wang
    • Beata Bochentyn
    • Piotr Jasiński
    2023 JOURNAL OF THE EUROPEAN CERAMIC SOCIETY

    A novel one-pot synthesis route leading to the formation of a wormhole-like structure was developed for the successful fabrication of porous YSZ and Ni-YSZ systems. This method involved co-precipitation in the presence of the micelle-forming agents CTAB/Pluronic P123 and crystallising NaCl. The obtained skeletons were mechanically stable and presented almost 50% uniform, open porosity without using any additional pore-formers. The fabricated 0.3 M CTAB/NaCl Ni-YSZ showed better long-term electrical stability in hydrogen than a traditional Ni-YSZ cermet. It resulted from the suppression of Ni structural changes throughout the anode scaffold. Moreover, higher electrochemical activity of this novel anode is expected due to the smaller particle sizes of Ni/YSZ, high homogeneity, highly developed TPB, and better interfacial interaction between the Ni and YSZ. Therefore, the novel soft-hard templating method is recognised as a promising route for the fabrication of the YSZ or Ni-YSZ with a highly developed microstructure and improved stability.

  • Facilitating free travel in the Schengen area—A position paper by the European Association for Biometrics
    • Christoph Busch
    • Farzin Deravi
    • Dinusha Frings
    • Els Kindt
    • Ralph Lessmann
    • Alexander Nouak
    • Jean Salomon
    • Mateus Achcar
    • Fernando Alonso-Fernandez
    • Daniel Bachenheimer
    • David Bethell
    • Josef Bigun
    • Matthew Brawley
    • Guido Brockmann
    • Enrique Cabello
    • Patrizio Campisi
    • Aleksandro Cepilovs
    • Miles Clee
    • Mickey Cohen
    • Christian Croll
    • Andrzej Czyżewski
    • Bernadette Dorizzi
    • Martin Drahansky
    • Paweł Drozdowski
    • Fankhauser Catherine
    • Julian Fierrez
    • Marta Gomez-Barrero
    • Georg Hasse
    • Richard Guest
    • Ekaterina Komleva
    • Sebastien Marcel
    • Gianluca Marcialis
    • Laurent Mercier
    • Emilio Mordini
    • Stefance Mouille
    • Pavlina Navratilova
    • Javier Ortega-Garcia
    • Dijana Petrovska
    • Norman Poh
    • Istvan Racz
    • Raghavendra Ramachandra
    • Christian Rathgeb
    • Christophe Remillet
    • Uwe Seidel
    • Luuk Spreeuwers
    • Brage Strand
    • Sirra Toivonen
    • Andreas Uhl
    2023 Pełny tekst IET Biometrics

    Due to migration, terror-threats and the viral pandemic, various EU member states have re-established internal border control or even closed their borders. European Association for Biometrics (EAB), a non-profit organisation, solicited the views of its members on ways which biometric technologies and services may be used to help with re-establishing open borders within the Schengen area while at the same time mitigating any adverse effects. From the responses received, this position paper was composed to identify ideas to re-establish free travel between the member states in the Schengen area. The paper covers the contending needs for security, open borders and fundamental rights as well as legal constraints that any technological solution must consider. A range of specific technologies for direct biometric recognition alongside complementary measures are outlined. The interrelated issues of ethical and societal considerations are also highlighted. Provided a holistic approach is adopted, it may be possible to reach a more optimal trade-off with regards to open borders while maintaining a high-level of security and protection of fundamental rights. European Association for Biometrics and its members can play an important role in fostering a shared understanding of security and mobility challenges and their solutions.

  • Factors affecting low-temperature cracking of asphalt pavements: analysis of field observations using the ordered logistic model
    • Dawid Ryś
    • Mariusz Jaczewski
    • Marek Pszczoła
    • Agnieszka Kamedulska
    • Bartosz Kamedulski
    2023 Pełny tekst International Journal of Pavement Engineering

    Accurate identification of factors that primarily affect the number of low-temperature cracks is crucial for selection of road materials and planning of pavement maintenance. Field investigations of lowtemperature cracks were performed in the years 2014 and 2020 on the same 68 road sections being in service in typical traffic conditions. The collected data were statistically analysed using the ordered logistic regression model. Comparison of the odds ratios which were calculated on the basis of the model enabled ordering of the selected factors from those having the greatest effect on lowtemperature cracking of pavements to those with the least influence: (1) pavement age, (2) type of asphalt concrete, (3) modification of bitumen, (4) climatic zone (on the basis of low performance grade temperature). The odds of a section belonging to the group of cracked sections decreased by half when a polymer-modified bitumen was used in its binder course and asphalt base. Regardless of the considered factors, the odds of a pavement section being classified into the group of heavily cracked sections are comparable. It means that some external factors, including quality of paving works and bitumen chemistry, may prove the most crucial.

  • Factors affecting the conclusion of an arrangement in restructuring proceedings: evidence from Poland
    • Błażej Prusak
    • Ulyana Zaremba
    • Paweł Galiński
    2023 Pełny tekst Ruch Prawniczy, Ekonomiczny i Socjologiczny

    The EU Restructuring Directive (2019/1023) requires Member States to provide a preventive restructuring framework for financially distressed entities that remain viable or are likely to readily restore economic viability. The first step to a successful restructuring is the approval of an arrangement between the debtor and creditors. The main research objective of the article is to identify factors affecting the conclusion of an arrangement in restructuring proceedings. In the process of filtering companies initiating a restructuring procedure, these factors are seen as increasing the probability of concluding an arrangement between debtor and creditors. Moreover, an additional research objective is to construct a turnaround prediction model aimed at assessing the probability of a conclusion of an arrangement in restructuring proceedings. The study covered the companies in Poland for which restructuring proceedings opened between 2016 and 2021 end-ed with the approval of an arrangement, and a similar number of companies that failed to restruc-ture successfully. Binary logistic regression was applied to achieve the aims of this study. The results show that two financial variables affected companies in terms of their chances to conclude the arrangement: the current ratio and return on assets were among the statistically significant indicators and they are characterized by higher values for debtors reaching the arrangement with their creditors. A direct positive relationship was also identified between the company’s lifespan and the outcome of the proceedings. The probability of the conclusion of the arrangement was also affected by the type of industry. Models assessing the probability of completing restructuring proceedings with an arrangement can be useful for insolvency practitioners and financial analysts during viability assessments.

  • FACTORS AFFECTING THE CONCLUSION OF AN ARRANGEMENT IN RESTRUCTURING PROCEEDINGS: EVIDENCE FROM POLAND
    • Błażej Prusak
    • Paweł Galiński
    2023 Pełny tekst

    The EU Restructuring Directive (2019/1023) requires Member States to provide a preventive restructuring framework for financially distressed entities that remain viable or are likely to readily restore economic viability. The first step to a successful restructuring is the approval of an arrangement between the debtor and creditors. The main research objective of the article is to identify factors affecting the conclusion of an arrangement in restructuring proceedings. In the process of filtering companies initiating a restructuring procedure, these factors are seen as increasing the probability of concluding an arrangement between debtor and creditors. Moreover, an additional research objective is to construct a turnaround prediction model aimed at assessing the probability of a conclusion of an arrangement in restructuring proceedings. The study covered the companies in Poland for which restructuring proceedings opened between 2016 and 2021 ended with the approval of an arrangement, and a similar number of companies that failed to restructure successfully. Binary logistic regression was applied to achieve the aims of this study. The results show that two financial variables affected companies in terms of their chances to conclude the arrangement: the current ratio and return on assets were among the statistically significant indicators and they are characterized by higher values for debtors reaching the arrangement with their creditors. A direct positive relationship was also identified between the company's lifespan and the outcome of the proceedings. The probability of the conclusion of the arrangement was also affected by the type of industry. Models assessing the probability of completing restructuring proceedings with an arrangement can be useful for insolvency practitioners and financial analysts during viability assessments.

  • Factors Affecting the Rheological Properties of Foods
    • Robert Tylingo
    2023

    In this chapter, engineering aspects concerning real body mechanics and the impact of respective food ingredients on said properties are presented together. Food is a complex matrix and each of macro and micro ingredients plays its role in the formation of rheologic properties, and minor changes in the basic ingredient structure may affect the change of these properties significantly. Basic analytic techniques are presented for the assessment of rheologic parameters. Furthermore, this chapter includes the evaluation of the impact of selected food ingredients, such as: proteins, saccharides, lipids on the creation of measurable, rheologic parameters of food products and their modification possibilities.

  • Failure characterisation of sandwich beams using integrated acoustic emission and digital image correlation techniques
    • Łukasz Pyrzowski
    • Magdalena Knak
    • Magdalena Rucka
    2023 Pełny tekst COMPOSITE STRUCTURES

    The paper presents the experimental study of the failure behaviour of sandwich beams subjected to bending. The samples examined are sandwich beams made of polyethylene terephthalate foam core and glass fibre-reinforced polymer laminate face sheets. In a series of experiments, it has been proposed to integrate diagnostic techniques with acoustic emission and digital image correlation to accurately track the cracking process on the surface as well as in the entire volume of the beam. The research programme carried out allowed observing various modes of failure in composite specimens. The results obtained showed that the integration of acoustic and optical diagnostic techniques provided complementary results and can be used successfully for failure monitoring in sandwich beams.

  • Fashion and Tourism: Parallel Stories of Two "Dream Marvels".
    • Maria Gravari-Barbas
    • Nadzeya Sabatini
    2023

    Fashion and tourism are two social, cultural, and economic phenomena that have both numerous connections and surprising similarities. These are not new: they have been built and developed since the beginnings of tourism as a modern social phenomenon, emerged in Europe in the context of the industrial revolution. They consolidated in the first decades of the 21st century, in a context where both phenomena have completed their “mass” cycle and are currently seeking alternative ways of expression and development. The chapter analyzes first the common characteristics of these two phenomena, fashion and tourism, as well as the challenges they are facing in the beginning of the 21st century. What can one learn from these proximities? What does the evolution of the practices, policies, and space planning of one phenomenon say about the other?

  • Fashion Games, Fashion in Games and Gamification in Fashion. A First Map
    • Alice Noris
    • Nadzeya Sabatini
    • Lorenzo Cantoni
    2023

    Fashion companies have been using different forms of entertainment such as film and television, sport, music, museums, and photography as inspiration sources and as communication and marketing channels for decades. However, in recent years, they have also started to consider the gaming world. While gaming offers a potential revenue stream from sales of physical and digital clothing, change in it is also the gateway to access new opportunities of the so-called metaverse. Moreover, the development of mixed realities might, in a sense, “democratize” the industry by offering at a lower price the digital version of products that attract customers. Through an analysis of secondary data and the study of three cases, this research aims to understand how fashion companies adopt and adapt digital games to develop their communication and marketing strategies, and how gaming companies exploit fashion to develop their products. The main goal is to analyze from an academic perspective how the gaming industry represents a communication and marketing channel in which creative companies can produce immersive experiences different from those available through other means. Finally, this article provides a map of the relationships between fashion and gaming by proposing three categories: gamification in fashion, fashion games and fashion in games.

  • Fast Algorithms for Identification of Time-Varying Systems with Both Smooth and Discontinuous Parameter Changes
    • Maciej Niedźwiecki
    • Artur Gańcza
    2023 Pełny tekst

    The problem of noncausal identification of a time-varying linear system subject to both smooth and occasional jump-type changes is considered and solved using the preestimation technique combined with the basis function approach to modeling the variability of system parameters. The proposed estimation algorithms yield very good parameter tracking results and are computationally attractive.

  • Fast Calibration-Free Single-Anchor Indoor Localization Based on Limited Number of ESPAR Antenna Radiation Patterns
    • Mateusz Groth
    • Krzysztof Nyka
    • Łukasz Kulas
    2023

    — In this article, we investigate how the calibrationfree single-anchor indoor localization algorithm developed for base stations equipped with electronically steerable parasitic array radiator (ESPAR) antennas can further be improved. By reducing the total number of ESPAR antenna radiation patterns used in localization process, one can significantly reduce the time needed for an object localization. Performed localization measurements involved different placement and number of reference nodes (RNs) used by the calibration-free singleanchor indoor localization algorithm, as well as different possible radiation patterns sets involving 6, 4 or 3 radiation patterns. Test results show that without significant deterioration of the overall accuracy one can easily speed up the algorithm execution time.

  • Fatigue life prediction of notched components under size effect using strain energy reformulated critical distance theory
    • Zhouyang Shuai
    • Shun-Peng Zhu
    • Jin-Chao He
    • Ding Liao
    • José A.F.O. Correia
    • Wojciech Macek
    • Ricardo Branco
    • Qingyuan Wang
    2023 INTERNATIONAL JOURNAL OF FATIGUE

    Notch and size effects show significant impact on the fatigue performance of engineering components, which deserves special attention. In this work, a strain energy reformulated critical distance theory was developed for fatigue life prediction of notched components under size effect. Experimental data of different notched specimens manufactured from GH4169, TC4, TC11 alloys and low carbon steel En3B were used for model validation and comparison. Results indicate the proposed model works better than the Yang’s and the Shen’s models.

  • Fatty acids as molecular carriers in cleavable antifungal conjugates
    • Michał Nowak
    • Andrzej Skwarecki
    • Joanna Pilch
    • Justyna Górska
    • Piotr Szweda
    • Maria Milewska
    • Sławomir Milewski
    2023 Pełny tekst EUROPEAN JOURNAL OF MEDICINAL CHEMISTRY

    Conjugates composed of C2-18 fatty acid (FA) residues as a molecular carrier and 5-fluorocytosine (5-FC) as an active agent, released upon the action of intracellular esterases on the ester bond between FA and “trimethyl lock” intramolecular linker, demonstrate good in vitro activity against human pathogenic yeasts of Candida spp. The minimal inhibitory concentrations (MIC) values for the most active conjugates containing caprylic (C8), capric (C10), lauric (C12), or myristic (C14) acid residues were in the 2–64 μg mL.

  • Fault detection and diagnostics of complex dynamic systems using Gaussian Process Models - nuclear power plant case study
    • Bartosz Puchalski
    2023

    The article examines the use of Gaussian Process Models to simulate the dynamic processes of a Pressurized Water nuclear Reactor for fault detection and diagnostics. The paper illustrates the potential of Gaussian Process Models as a tool for monitoring and predicting various fault conditions in Pressurized Water nuclear Reactor power plants, including reactor coolant flow and temperature variations, deviations from nominal working point or faulty power measurements. The article discusses the characteristics and benefits of Gaussian Process Models and how they can be utilized to improve: the reliability and accuracy of nuclear power plant anomaly detection, fault diagnosis and decision making process in states of emergency. Overall, this paper highlights the capabilities of Gaussian Process Models to enhance the safety, reliability and efficiency of nuclear power plants. The results of this study are expected to provide valuable insights for engineers and researchers in the fields of control engineering and nuclear power.

  • FDTD Method for Electromagnetic Simulations in Media Described by Time-Fractional Constitutive Relations
    • Piotr Pietruszka
    • Tomasz Stefański
    • Jacek Gulgowski
    2023 Pełny tekst Applied Sciences-Basel

    In this paper, the finite-difference time-domain (FDTD) method is derived for electromagnetic simulations in media described by the time-fractional (TF) constitutive relations. TF Maxwell’s equations are derived based on these constitutive relations and the Grünwald–Letnikov definition of a fractional derivative. Then the FDTD algorithm, which includes memory effects and energy dissipation of the considered media, is introduced. Finally, one-dimensional signal propagation in such electromagnetic media is considered. The proposed FDTD method is derived based on a discrete approximation of the Grünwald–Letnikov definition of the fractional derivative and evaluated in a code. The stability condition is derived for the proposed FDTD method based on a numerical dispersion relation. The obtained numerical results are compared with the outcomes of reference frequency-domain simulations, proving the accuracy of the proposed approach. However, high spatial resolution is required in order to obtain accurate results. The developed FDTD method is, unfortunately, computation and memory demanding when compared to the ordinary FDTD algorithm.

  • Feasibility Study of Biohydrogen Production from Acid Cheese Whey via Lactate-Driven Dark Fermentation
    • Brenda Aranda-Jaramillo
    • Elizabeth León-Becerril
    • Oscar Aguilar-Juárez
    • Roberto Castro Munoz
    • Octavio García-Depraect
    2023 Pełny tekst Fermentation

    The high loading of lactic acid bacteria (LAB) present in cheese whey still limits its use as hydrogen feedstock. This study aims to investigate the feasibility of producing hydrogen from acid cheese whey via lactate-driven dark fermentation (LD-DF). Mesophilic batch fermentations were performed with delipidated acid cheese whey at a fixed pH of 5.8 and driven by an acidogenic bacterial culture containing LAB and lactate-oxidizing hydrogen producers (LO-HPB). The results obtained indicated that it is technically feasible to produce hydrogen from undiluted cheese whey through lactate oxidation-mediated fermentation. It was elucidated that the acidogenic fermentation of cheese whey followed a two-step lactate-type fermentation, in which fermentable carbohydrates were first converted into lactate, and then lactate was metabolized into hydrogen with the co-production of butyrate. The hydrogen yield and the maximum volumetric hydrogen production rate achieved were 44.5 ± 2.9 NmL/g-CODfed and 1.9 NL/L-d, respectively. Further microbial community analysis revealed that Lactobacillus, Clostridium, and Klebsiella were the dominant bacterial genera when the hydrogen production rate peaked. It was therefore suggested that the metabolic potential behind the association between LAB and LO-HPB was important in driving the two-step lactate-type fermentation. Overall, the LD-DF can be a strategic hydrogen-producing pathway to be implemented with cheese whey.

  • Federated Learning in Healthcare Industry: Mammography Case Study
    • Krystian Zieliński
    • Natalia Kowalczyk
    • Tomasz Kocejko
    • Magdalena Mazur-Milecka
    • Tomasz Neumann
    • Jacek Rumiński
    2023

    The paper focuses on the role of federated learning in a healthcare environment. The experimental setup involved different healthcare providers, each with their datasets. A comparison was made between training a deep learning model using traditional methods, where all the data is stored in one place, and using federated learning, where the data is distributed among the workers. The experiment aimed to identify possible challenges that could arise when training a model in a federated learning scenario, including the impact of federated learning on the obtained measures for breast density classification and examining the impact of data preprocessing and domain adaptation. The results indicate that using federated learning deep-learning models can be effectively trained on distributed healthcare data, performing similarly to the traditional approach while providing additional benefits such as improved data privacy and security. However, domain adaptation and data heterogeneity must be carefully addressed to achieve optimal performance in federated learning.

  • FEM modelling of screw displacement pile interaction with subsoil
    • Paweł Więcławski
    • Adam Krasiński
    2023 Pełny tekst Archives of Civil Engineering

    Predicting the-settlement characteristics of piles is an important element in the designing of pile foundations. The most reliable method in evaluating pile-soil interaction is the static load test, preferably performed with instrumentation for measuring shaft and pile base resistances. This, however, is a mostly post-implementation test. In the design phase, prediction methods are needed, in which numerical simulations play an increasingly popular role. This article proposes a procedure for numerically modeling the interaction of screw displacement piles with soil using the ZSoil 2D FEM program. The procedure takes into account technological characteristics of this type of pile, such as the process of soil expansion during the screwing-in of the auger and the pressure of concrete mix after pile concreting. They significantly affect the soil stress state, which is a key parameter for the pile load capacity. Geotechnical parameters of the subsoil were adopted from CPTU probing and laboratory tests. Due to the physical complexity, a constitutive soil model "Hardening Soil" (HS) was used in the analyses. The modeling procedure was calibrated on the basis of the static load test results of several instrumented piles, which were carried out as part of the "DPDT-Auger" research project. As a result of these calibrations, generalized recommendations were derived for an entire single pile modeling process with the axisymmetric system of ZSoil program. These can be useful in the reliable FEM prediction of the-characteristics for screw displacement piles for practical engineering purposes.

  • Fe-modified Mn2CuO4 spinel oxides: coatings based on abundant elements for solid oxide cell interconnects
    • Justyna Ignaczak
    • Lunjie Zeng
    • Dario Ferreira Sanchez
    • Małgorzata Makowska
    • Karolina Górnicka
    • Krystian Lankauf
    • Jakub Karczewski
    • Piotr Jasiński
    • Sebastian Molin
    2023 INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

    The current state of the art steel interconnect coating materials are based on critical raw material - Co-oxide spinels. Replacing Co-oxide spinels with alternative, abundant materials can reduce the dependence on the critical raw materials. Cobalt-free coatings with the general formula Mn2-xCuFexO4, where x = 0, 0.1, 0.3, were electrophoretically deposited on a ferritic stainless-steel support and evaluated. Prior to deposition, the powders were prepared by a soft chemistry process and studied in terms of crystallographic phase analysis, electrical conductivity, thermal expansion, and sinterability behaviour. Coated steel samples were oxidised in an air atmosphere at 750 °C for 3000 h. In parallel, a state-of-the-art MnCo2O4 spinel oxide was tested as a reference. The coatings and oxide scale microstructures of the surfaces and cross-sections were examined by XRD, and SEM-EDX. TEM-EDX, XRF, and micro-XRD were also performed on the cross-section lamellae. The electrical properties of the steel-coating system were evaluated by Area Specific Resistance measurement. The results confirm that Mn–Cu–Fe oxides exhibit higher conductivity and lower TEC than Mn–Co oxide. Based on the obtained results, it might be concluded that the proposed coatings are a promising alternative to coatings that contain cobalt.

  • Fibrillar aggregates in powdered milk
    • Jarosław Wawer
    • Martyna Andrukajtis
    • Jakub Karczewski
    • Anna Zielińska-Jurek
    • Rafał Piątek
    2023 JOURNAL OF DAIRY RESEARCH

    This research paper addresses the hypothesis that powdered milk may contain amyloid fibrils. Amyloids are fibrillar aggregates of proteins. Up to this time, research on the presence of amyloids in food products are scarce. To check the hypothesis we performed thioflavin T fluorescence assay, X-ray powder diffraction, atomic force microscopy and fluorescence microscopy imaging. Our preliminary results show that commercially available milks contain fibrils that have features characteristic to amyloids. The obtained results can be interpreted in two opposite ways. The presence of amyloids could be considered as a hazard due to the fact that food products may induce amyloid related diseases. On the other hand, the presence of amyloids in traditionally consumed foodstuffs could serve as proof that fibrils of food proteins do not pose a threat for consumers.

  • Filter-Hilbert Method for Automatic Correction of Non-Anechoic Antenna Measurements with Embedded Self-Calibration Mechanism
    • Adrian Bekasiewicz
    • Vorya Waladi
    2023 MEASUREMENT

    One of the most important steps in the process of antenna development involves measurements of its prototype. Far-field performance of radiators is normally characterized in strictly controlled environments such as anechoic chambers which can ensure certification-grade accuracy. Unfortunately, they are also characterized by high construction costs which might not be justified for low-budget research and/or teaching-related activities. Alternatively, the radiation characteristics can be obtained in non-anechoic test sites which neglect the expensive components such as shielding and/or absorbing materials. Although the noise from external radiation sources and multi-path interferences renders direct measurements in such conditions useless for drawing conclusions on antenna performance, the quality of responses can be substantially increased using appropriate post-processing. Unfortunately, the existing techniques are difficult to set-up and prone to failure which makes them of limited use for day-to-day measurements. In this work, a correction framework for non-anechoic measurements based on a set of Hilbert filters automatically adapted to propagation conditions within the test-site has been proposed. The presented method has been validated based on three example antennas and a total of 25 experiments covering 15 unique frequencies of interest. A benchmark of the method against the state-of-the-art correction techniques has also been performed.

  • Financial aspects of supporting Ukrainian refugees
    • Krystyna Gomółka
    • Piotr Kasprzak
    2023

    Warfare in Ukraine meant that in 2022 many countries, including Poland and other European, focused mainly on helping refugees from Ukraine and humanitarian transports. The assistance took on various forms - from basic humanitarian support, through in-kind help, financial and military assistance. Poland launched its humanitarian aid in the first days of the conflict. The aid provided by each country varies. It should be noted, however, that in each case it is possible to quantify it economically, i.e. to determine its scope, role and importance, and above all, its economic (financial) dimension. The aim of this article is to present various forms of assistance from European countries, with particular emphasis on Poland. As part of the research, the latest available literature on the subject, industry reports and sometimes press articles were used.

  • Financial Consequences of the Introduction of the Fit For 55 on the Example of Poland
    • Justyna Kujawska
    • Piotr Kasprzak
    2023

    In Europe and in Poland, there is a growing conviction that climate action is a necessity. When creating long-term strategies or making current decisions, companies are increasingly taking into account issues related to sustainable development and reducing CO2 emissions. Following the signing of the Paris Agreement in 2015, countries around the world pledged to reduce greenhouse gas emissions by 2050 so that the average temperature increase does not exceed 2°C, with the ambition to reach 1.5°C. EU countries have agreed to tighten climate regulations by adopting and implementing the Fit For 55 package. The aim of this study is to present the financial consequences of the introduction of the Fit For 55 package of regulations. The Fit for 55 package is related to Europe's energy transition and is at the initial stage of implementation, hence the lack of broader studies on the subject. The research method includes an analysis of available reports estimating the economic impact of the Fit for 55 package and statistical information. The research shows that the costs of Polish's energy transformation will be very high (over € 500 billion), which is only an estimate, taking into account the current level of prices and knowledge, because many technologies to be used are only at the research stage. For most EU countries, this will entail the introduction of new taxes, fees, as well as legal and administrative restrictions, which will undoubtedly result in higher prices of individual goods and services. In addition, the introduced regulations will lead to the cessation of the use of certain technologies, e.g. combustion cars, coal-fired power plants, or a reduction in the turnover of, for example, real estate that does not meet certain energy efficiency requirements.

  • Finite element modeling of plastic hinges based on ductility demand-capacity method using nonlinear material for dynamic analysis
    • Karol Grębowski
    • Krzysztof Wilde
    • Mikołaj Miśkiewicz
    2023 Pełny tekst INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING

    The article discusses modeling plastic hinges in reinforced concrete interme-diate supports using finite elements methods. The ductility demand-capacitymethod was used to determine the geometrical parameters of cross-section plas-ticization zones, their ability to move and rotate, as well as their ductility. Dueto the varied geometry and stiffness of the supports and their nonlinear behav-ior under dynamic load, this method was concluded to be imperfect. Therefore,an improved algorithm was proposed by determining the main parameters ofplastic hinges depending on the degree of concrete degradation according toLubliner’s assumptions. The new algorithm has been implemented in the formof mathematical equations. It was subsequently used, at the structure designstage, to perform numerical calculations based on the finite element method.

  • Fire-induced spalling of ultra-high performance concrete: A systematic critical review
    • Mugahed Amran
    • Gunasekaran Murali
    • Marzena Kurpińska
    • Moncef L. Nehdi
    2023 CONSTRUCTION AND BUILDING MATERIALS

    Ultra-high performance concrete (UHPC) is a novel concrete class characterized by a compressive strength of more than 150 MPa. One of the most significant drawbacks of employing UHPC is that is very low permeability owing to its great compactness of dense structure increases the risk of fire-induced spalling. It is challenging for fire safety and structural engineers to predict and analyze this issue due to the lack of widely accepted and reliable models for concrete spalling. Therefore, understanding the fire-spalling characteristics of UHPC exposed to high temperature or fire is vital for ensuring the safety of a UHPC-based structural fire design. To date, the fireinduced spalling behaviour of UHPC has not been thoroughly investigated. To address this informational gap, this article aims to assess various aspects of UHPC by focusing on fire-induced spalling and its influencing factors, spalling mechanism, microstructure characterization, prevention measures, and mitigation strategies. Moreover, this critical review summarizes and evaluates the results of thermal spalling tests and fire-induced spalling modeling undertaken on UHPC in developing a manual regulation protocol. This paper aims to provide insights into improving the existing design guidelines for the fire-spalling-resistant design of UHPC members, this facilitating wide-scale adoption of robust and sustainable UHPC. Given the merits of the study topic, the review strategies and initiatives can then be leveraged to give insight into areas that will be highly beneficial for future experiments and research of UHPC applications by research centers and construction industries globally.

  • Flexible syngas-biogas-hydrogen fueling spark-ignition engine behaviors with optimized fuel compositions and control parameters
    • Van Ga Bui
    • Thi Minh Tu Bui
    • Van Nam Tran
    • Zuohua Huang
    • Anh Tuan Hoang
    • Wiesław Tarełko
    • Van Hung Bui
    • Xuan Mai Pham
    • Phuoc Quy Phong Nguyen
    2023 INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

    This paper presents the results research on the optimal fuel compositions and the control parameters of the spark ignition engine fueled with syngas-biogas-hydrogen for the purpose of setting up a flexible electronic control unit for the engine working in a solar-biomass hybrid renewable energy system. In syngas-biogas-hydrogen mixture, the optimal content of hydrogen and biogas is 20% and 30%, respectively. Exceeding these thresholds, the improvement of engine performance is moderate, but the pollution emission increases strongly. The optimal advanced ignition angle is 38°CA, 24°CA, and 18°CA for syngas, biogas, and hydrogen, respectively. With the same content of hydrogen or biogas in the mixture with syngas, the advanced ignition angle of the hydrogen-syngas blend is less than that of the syngas-biogas blend by about 4°CA at the engine speed of 3000 rpm. The derating power of the engine is 30% and 23% as switching from the hydrogen and biogas fueling mode to the syngas fueling mode, respectively. However, NOx emission of the engine increase from 200 ppm (for syngas) to 2800 ppm (for biogas) and to over 6000 ppm (for hydrogen). The optimal advanced ignition angle, the optimal equivalence ratio of the syngas-biogas-hydrogen fuel mixture vary within the limits of the respective values for syngas and hydrogen. To improve the engine efficiency and reduce pollutant emissions, the loading control system of the engine should prioritize the adjustment of the fuel flow and then the adjustment of the air-fuel mixture flow.

  • Flood Modelling and Risk Analysis of Cinan Feizuo Flood Protection Area, Huaihe River Basin
    • Umar Farooq
    • Abubakr Taha Bakheit Taha
    • Fuchang Tian
    • Ximin Yuan
    • Muhammad Ajmal
    • Irfan Ullah
    • Mahmood Ahmad
    2023 Pełny tekst Atmosphere

    This study evaluated multiple aspects of flood risks and effects on the Cinan Feizuo flood protection area in the Huaihe River basin. Flooding remains a leading problem for infrastructure, especially in urban, residential areas of the region. Effective flood modeling for urbanized floodplains is challenging, but MIKE (ID-2D) is paramount for analyzing and quantifying the risk in the vulnerable region. The Saint-Venant equation and a one-dimensional (1D) MIKE 11 model were used to understand the flood dynamics in the Huaihe River, and a two-dimensional (2D) MIKE 21 model was applied to assess the risk in the Cinan Feizuo flood protection area. The finite volume method (FVM) was used for discrete grid problems, and the models were coupled through the weir equation to find the flow volume from the 1D domain to the 2D domain to investigate water level changes. Flood inundation maps were generated for the flood protection area. The maximum discharge, velocity, and submerged depth for 50- and 100-year flood events were assessed with flood risk. Chenbei indicated a high flood risk level in 50 to 100 years in which the water level exceeds a high level and inundates the maximum area with minimum time. Conversely, the 100-year flood inundation in the flood protection area was comparatively higher than the 50-year flood, with a lower time step. The risk analysis identified significant damage caused by the flood over the target regions. The findings of this study provide technical support for flood risk analysis and loss assessment within the flood protection area and have important reference values for regional flood control, disaster reduction decision making, and constructive planning.

  • Flow boiling of R1233zd(E) in a 3 mm vertical tube at moderate and high reduced pressures
    • Michał Pysz
    • Dariusz Mikielewicz
    2023 Pełny tekst EXPERIMENTAL THERMAL AND FLUID SCIENCE

    The results of flow boiling of R1233zd(E) in a 3 mm vertical stainless steel tube are presented at moderate and high saturation temperatures. Integral flow characteristics in the form of pressure drop and heat transfer coefficient are discussed for saturation temperatures ranging from 115 to 145 °C (corresponding reduced pressures from 0.2 to 0.7), mass velocity of 800 kg/m2s and heat flux of 20 kW/m2. All of the obtained heat transfer trends initially decrease with vapor quality and then do not change or increase with vapor quality. The decrease is connected to the dominance of the nucleate boiling phenomenon. The subsequent increase in heat transfer indicates the increased effect of convective boiling. The rate of the increase depends on the value of reduced pressure (the smaller the reduced pressure the higher the rate). The obtained data have been compared with the predictions of the in-house model and some well-known two-phase flow correlations. The in-house model predictions presented the highest accuracy, with MAPE equal to 23.17 % for R1233zd(E) and 19.23 % for R245fa (data from literature).

  • Flow Maps and Flow Patterns of R1233zd(E) in a Circular Minichannel at Low, Medium and High Values of Saturation Pressure
    • Stanisław Głuch
    • Michał Pysz
    • Dariusz Mikielewicz
    2023 Pełny tekst

    There is a gap in knowledge regarding the flow pattern of low-boiling working fluids in the range of high saturation temperatures (above 120°C) and medium and high reduced pressures (0.5-0.9). Data are present in the literature for similar values of reduced pressures, but for lower values of saturation temperature. This is due to the existing refrigeration applications of these working fluids. At high values of reduced pressure, the density of the gas phase is relatively high, and the density of the liquid phase is low. There is a low specific volume difference between the liquid and gas phases. The liquid phase has a low surface tension value. The gas phase has a relatively high viscosity, and the liquid phase has a reduced value of viscosity. These changes in the parameters of refrigerants cause significant differences in flow structures. At a low value of reduced pressure, 0.2, the occurrence of annular flow was observed already at a quality of 0.07 for a mass velocity of G=355 [kg/(m^2·s)], while for a reduced pressure of 0.8, annular flow occurs much later, at a quality of 0.47 for the same mass velocity. Mass velocity flow maps in a function of quality for constant values of reduced pressure and flow maps for reduced pressure as a function of quality at constant mass velocity are presented. Flow maps are compared with correlations for transition lines between intermittent and annular flow structures from literature. Authors new correlation for transition line for researched conditions is presented. New prediction method is the only one which managed to predict transition to annular flow at high values of reduced pressure for collected experimental data.

  • Fluid–solid interaction on a thin platelet with high-velocity flow: vibration modelling and experiment
    • Piotr Ziolkowski
    • Tomasz Ochrymiuk
    • Victor Eremeev
    2023 Pełny tekst CONTINUUM MECHANICS AND THERMODYNAMICS

    The paper concerns the nonlinear behaviour of a thin platelet that is streamlined in an aerodynamic tunnel. The air velocity in the aerodynamic tunnel was at 858.9 km/h or 0.7 Ma (Ma—Mach number is a dimensionless quantity in fluid dynamics representing the ratio of flow velocity past a boundary to the local speed of sound). This experiment was numerically simulated using FSI (fluid–solid interaction) tools, namely the coupling between the strength and flow code. The strength code uses the finite element method, while the flow code is based on the finite volume method. The coupling between the codes was made by means of an interface that transmitted the relevant data and results between the two codes. The paper discusses the methodology of this coupling. The study also highlights the phenomena occurring during the interaction of flow with the plate with emphasis on their nonlinear character.

  • FORECASTING BIOGAS FORMATION IN LANDFILLS
    • Zbigniew Kneba
    • Jacek Kropiwnicki
    • Jakub Hadrzyński
    • Maciej Ziółkowski
    2023 Pełny tekst Acta Mechanica et Automatica

    : The aim of the present research was to develop a mathematical model for estimating the amount of viscous gas generated as a function of weather conditions. Due to the lack of models for predicting gas formation caused by sudden changes in weather conditions in the literature, such a model was developed in this study using the parameters of landfills recorded for over a year. The effect of temperature on landfill gas production has proved to be of particular interest. We constructed an algorithm for calculating the amount of the produced gas. The model developed in this study could improve the power control of the landfill power plant.

  • Four Degree-of-Freedom Hydrodynamic Maneuvering Model of a Small Azipod-Actuated Ship With Application to Onboard Decision Support Systems
    • Mathias Marley
    • Roger Skjetne
    • Mateusz Gil
    • Przemysław Krata
    2023 Pełny tekst IEEE Access

    The main contribution of this paper is a numerical ship motion model of NTNU’s research vessel Gunnerus, capturing the surge, sway, roll, and yaw dynamics when sailing in uniform and steady currents. The model utilizes a crossflow drag formulation for the transverse viscous loads, and it includes a nonlinear formulation for the propulsion and steering loads provided by two azipod thrusters. A wide range of experimental data obtained from sea trials are used for model calibration and validation. The model is intended for development of Decision Support Systems (DSS) that provide the helmsman with recommendations for safe maneuvers. As a demonstration, the model is used to generate input to a previously proposed DSS solution, which uses offline simulations to create a database of the critical navigation area for different encounter scenarios. Additionally, we propose a DSS solution that uses online simulations to predict the future ship trajectory under guidance of a virtual autopilot. The virtual autopilot is designed using a novel hybrid control barrier function formulation to predict the need of evasive maneuvers for collision avoidance.

  • Fractographical quantitative analysis of EN-AW 2024 aluminum alloy after creep pre-strain and LCF loading
    • Wojciech Macek
    • Adam Tomczyk
    • Ricardo Branco
    • Michał Dobrzyński
    • Andrzej Seweryn
    2023 ENGINEERING FRACTURE MECHANICS

    This paper explores the applicability of a new damage parameter combining both fracture surface topography and loading features to estimate the fatigue lifetime under creep pre-strain and low-cycle fatigue loading. Fractures of EN-AW 2024 aluminum alloy caused by mixed creep and low-cycle fatigue loading are experimentally characterized and quantified via surface topography analysis. The specimens were preliminary damaged in a creep process at elevated temperature (100 °C, 200 °C, or 300 °C) considering two strain levels for each temperature. The specimens with preliminary damage were then subjected to fatigue tests at room temperature. The post-failure fracture surfaces were examined with an optical profilometer, and the focus was placed on the relationship between the creep-fatigue damage and the associated fracture surface topography parameters. In addition, an original fatigue life prediction model based on both the surface topography values and the applied strains was proposed and verified. The proposed model can be helpful for post-mortem analysis of engineering components subjected to fatigue loading accounting for creep pre-strain.

  • Fractographic-fractal dimension correlation with crack initiation and fatigue life for notched aluminium alloys under bending load
    • Wojciech Macek
    • Dariusz Rozumek
    • Sebastian Faszynka
    • Ricardo Branco
    • Shun-Peng Zhu
    • Reza Masoudi Nejad
    2023 Pełny tekst ENGINEERING FAILURE ANALYSIS

    In this study, fatigue fracture surfaces of aluminium alloy 2017-T4 notched specimens were investigated under cyclic bending to find an alternative failure loading index.. The surface topographies were measured on the entire fracture area with an optical profilometer for different loading conditions. Fatigue crack initiation life Ni and total fatigue life Nf were examined using standard surface topography parameters (such as, root mean square height Sq, arithmetical mean height Sa, maximum height Sz) and non-standard surface topography parameters (such as, fractal dimension Df). Fatigue life assessment was successfully performed by combining both fracture surface topography and stress state features. The results show that the fracture plane geometry, expressed by the fractographic-fractal dimension, can facilitate the estimation of post-failure loading history.

  • Fracture Surface Topography Parameters for S235JR Steel Adhesive Joints After Fatigue Shear Testing
    • Andrzej Kubit
    • Wojciech Macek
    • Władysław Zielecki
    • Paulina Szawara
    • Mariusz Kłonica
    2023 Pełny tekst Advances in Science and Technology Research Journal

    This paper presents the experimental results of a study investigating the effect of holes and notches made on the overlap ends on the strength of adhesive joints. Single-lap joints made of S235JR steel sheets bonded with Araldite 2024-2 epoxy adhesive were tested. For comparative reasons, static shear strength tests and high-cycle fatigue strength tests were performed. Adhesive-filled joints having three holes, each with a diameter of 3 mm, and notches, each 3 mm wide and 4 mm long, were tested and compared with reference joints, i.e. without modification. The assumption was to determine whether the structural modifications would reduce the peak peel and shear stresses that are typical of this type of joints. Results of the static strength tests showed no significant effect of the applied modifications on the strength of the joints. However, in terms of fatigue strength, the results demonstrated a significant improvement in fatigue life, the value of which increased in the low-cycle fatigue region by 328.6% for the joint with notches and by 640.8% for the joint with holes. A smaller yet still positive effect of the applied modifications was shown for high-cycle fatigue. For a variable load with the maximum value of 9 MPa, the fatigue life increased by 215.9% for the variant with notches and by 183.3% for the variant with holes. Surface topography of fatigue fractures was examined by determining roughness parameters on the overlap ends in the samples. Significant differences were shown, with the selected roughness parameters being significantly lower for the reference variant than for the variants with notches and holes. It was shown that the applied structural modifications led to increasing the fatigue strength to 8.5 MPa for the limit number of cycles equal to 2×106, when compared to the reference variant for which the fatigue strength was 8 MPa.

  • Free trade with the former COMECON Countries as Unequal Exchange
    • Marta Kuc-Czarnecka
    • Magdalena Olczyk
    • Andrea Saltelli,
    • Erik, S. Reinert
    2023 Pełny tekst

    Two authors of this chapter were born to the East of what was once The Iron Curtain and two to the West. From both angles, the two systems – capitalism and communism – seemed to be as contrary to each other as possible. Few people are aware that in terms of industrial and trade policy, both classical capitalism and communism had a common root in the theories of German economist Friedrich List (1789-1846) (List, 1841). In fact, for the 200th anniversary of his birth in 1989, both East Germany (DDR) and West Germany (Deutsche Bundespost) celebrated Friedrich List's anniversary with postage-stamps. The two enemies who had split Germany between them even chose the same portrait of their common hero! However, after the collapse of the Berlin Wall, the policy that was forced upon the former COMECON countries was not the old capitalism honoured by West Germany in 1989. Capitalist theory (but not practice) had given way to neoliberalism, a system that does not see any difference between economic activities. The theory that came out as a winner at the end of the Cold War was essentially David Ricardo's (1817) theory of international trade, restated by US economist Paul Samuelson (1948). Samuelson 'proved' that free trade, regardless of what was traded, would create a movement towards factor-price equalization (that the price of the factors of production, capital and labour) would tend to equalize across the globe. This neoliberal theory was immediately forced upon the former communist countries, leading to different degrees of deindustrialization.