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  • The effect of preliminary creep-strain on material behavior under LCF tension/compression and pure torsion regimes
    • Adam Tomczyk
    • Wojciech Grodzki
    • Andrzej Seweryn
    2024 INTERNATIONAL JOURNAL OF FATIGUE

    This paper presents the results of experimental tests of monotonic tension and torsion, creep-rupture and preliminary creep at 200C and 300C, as well as low-cycle fatigue of 2024 T3511 aluminum alloy. The fatigue process was conducted at room temperature for uniaxial tension/compression and torsion. The as-received material and pre-deformed material were also investigated during creep at elevated temperature. Basic monotonic, creep and fatigue characteristics of the material were determined. Detailed micro- and macroscopic analyses of fracture surfaces (scanning electron microscopy, SEM) were carried out. The influence of different creep pre-deformation histories at elevated temperature on the behavior of the studied alloy were characterized with respect to monotonic and cyclic loads at room temperature.

  • The Effect of Steaming Beech, Birch and Maple Woods on Qualitative Indicators of the Surface
    • Michal Dudiak
    • Richard Kminiak
    • Adrian Banski,
    • Daniel Chuchała
    2024 Pełny tekst Coatings

    This work presents the effect of steaming beech, birch and maple woods on the resulting quality of the milled wood surface. The steaming process of the studied woods results in a targeted change in the color of the wood, which changes from the original light white-gray color to fine reddishbrown to dark brown color shades that are more or less saturated depending on the temperature of the saturated water steam. The color changes achieved during the modification process were identified using coordinates in the CIE L*a*b* color space. The achieved color changes were described through the total color difference of ΔE* and defined through classification grades using a color scale. The technological process of wood steaming with saturated water steam for the purpose of a targeted change in the color of the wood and experimental measurements of the roughness of the milled wood surface proved that the wood steaming process has a positive effect on the roughness of the wood surface of the investigated trees, depending on the steaming temperature. The reduction of roughness in the process of the modification of beech wood compared with native wood was at the temperature of the saturated water steam as follows: tI = 105 ± 2.5 ◦C by Ra = 12.3%, at tII = 125 ± 2.5 ◦C by Ra = 15.4%, at tIII = 135 ± 2.5 ◦C by Ra = 16.9%. By modifying birch wood at tIII = 135 ± 2.5 ◦C, the roughness decreased by Ra = 13.4%; the surface roughness decreased by Ra = 15.8% compared with native wood by modifying maple wood. The roughness of the milled surface of modified wood in individual treatment modes decreased compared with native wood, which means that the milled surface of modified wood is of a better quality, which is positive for its practical use.

  • The effect of using jug-type water filters on selected metals concentration in tap water – a case study
    • Hubert Kwiatkowski
    • Ksawery Kreft
    • Oskar Ronda
    • Bartłomiej Cieślik
    2024 JOURNAL OF WATER AND HEALTH

    In this study, the effect of the filtration process on Na, K, Mg, Ca, Fe and Zn concentration in water, using filters from one of the leading European manufacturers, was investigated. The increase in Na (up to 300%) and K concentration (up to 320%) at the beginning of jug filter usage was reported. A decrease in Ca, Fe and Zn concentration was observed. Standard filters remove 80–90% of Mg from tap water at the beginning of the usage, while magnesium-enriching ones slightly increase its concentration – from around 8 to 12–25 mg/L. Significant changes in the filter’s operating characteristics were also observed for other studied elements as they wore out. Using Mg-enriching filters can increase magnesium intake from 4–5 to 6–15% of the recommended daily dose from water consumption. The results were also discussed regarding the amounts of macroelements found in commercially available bottled water. The magnesium concentration in tap water after filtration through magnesium-enriching filters was lower compared to bottled mineral waters. The authors note a scope for the development of water filter production technology, in particular, the need to develop filters that more efficiently enrich water with magnesium and do not increase sodium concentration

  • The Effect of Varying the Light Spectrum of a Scene on the Localisation of Photogrammetric Features
    • Paweł Burdziakowski
    2024 Pełny tekst Remote Sensing

    In modern digital photogrammetry, an image is usually registered via a digital matrix with an array of colour filters. From the registration of the image until feature points are detected on the image, the image is subjected to a series of calculations, i.e., demosaicing and conversion to greyscale, among others. These algorithms respond differently to the varying light spectrum of the scene, which consequently results in the feature location changing. In this study, the effect of scene illumination on the localisation of a feature in an image is presented. The demosaicing and greyscale conversion algorithms that produce the largest and smallest deviation of the feature from the reference point were assessed. Twelve different illumination settings from polychromatic light to monochromatic light were developed and performed, and five different demosaicing algorithms and five different methods of converting a colour image to greyscale were analysed. A total of 300 different cases were examined. As the study shows, the lowest deviation in the polychromatic light domain was achieved for light with a colour temperature of 5600 K and 5000 K, while in the monochromatic light domain, it was achieved for light with a green colour. Demosaicing methods have a significant effect on the localisation of a feature, and so the smallest feature deviation was achieved for smooth hue-type demosaicing, while for greyscale conversion, it was achieved for the mean type. Demosaicing and greyscale conversion methods for monochrome light had no effect. The article discusses the problem and concludes with recommendations and suggestions in the area of illuminating the scene with artificial light and the application of the algorithms, in order to achieve the highest accuracy using photogrammetric methods.

  • The efficiency of bankruptcy proceedings and the severity of insolvency regulations in view of the implementation of the New Opportunity Policy
    • Przemysław Banasik
    • Sylwia Morawska
    • Błażej Prusak
    • Michał Łukowski
    • Katarzyna Pustułka
    2024 International Journal of Management and Economics

    The article investigates the relationship between the efficiency of insolvency proceedings, as measured by their duration, and measures the severity of bankruptcy law toward debtors in 27 countries, of which 23 are EU. This objective was achieved using quantitative methods – Pearson’s correlation, pooled panel regression and Granger causality. Research shows no direct correlation between the two variables mentioned above. The increase in sanctions in bankruptcy law contributed to a decrease in the efficiency of insolvency proceedings. In addition, less stringent conditions concerning the time taken to file a bankruptcy petition translated into a shorter duration of insolvency proceedings. Therefore, supporting the New Opportunity Policy, we recommend that regulators focus on softening the legal requirements for filing a bankruptcy petition, for setting a time limit for filing and on reducing the sanctions for honest debtors, including those imposed for failure to file for bankruptcy within the period prescribed by law.

  • The experimental and numerical investigation of fracture behaviour in PMMA notched specimens under biaxial loading conditions – Tension with torsion
    • Elżbieta Bura
    • Wojciech Grodzki
    • Andrzej Seweryn
    2024 Pełny tekst ENGINEERING FRACTURE MECHANICS

    This paper presents the results of experimental fracture test of flat PMMA specimens under biaxial loading condition tension with torsion (proportional). The specimens were made in two thicknesses: 5 and 15 mm and were weakened with V-type edge notches with different root radii: 0.5; 2 and 10 mm. Thanks to the ARAMIS 3D 4 M non-contact vision system, measurement of the elongation and twist angle were recorded. During experimental part all of the deformation processes were observed using PHANTOM cameras. Obtained records made it possible to precisely indicate the moment of crack initiation (tensile force and torsional moment values). Using the microscopic observations the location of crack initiations were determined. Results obtained for biaxial loading were compared with those obtained for uniaxial tension and torsion. Based on experimental data the numerical calculation with FEM were carried out. The principal stress and plastic strain distribution under critical load, were obtained. The points of occurrence of stress maxima and plastic strain were indicated, which were taken as potential crack initiation sites. On the basis of the stress and plastic strain values measured at the critical points, a stress–strain fracture criterion was formulated, which was then positively verified. Additionally, new form of stress–strain fracture criterion was proposed. The bilinear form of the fracture criterion can be successfully used to predict fracture in PMMA flat specimens, regardless of the notch root radius, type of load or element thickness.

  • The exposure to UV filters: Prevalence, effects, possible molecular mechanisms of action and interactions within mixtures
    • Alexandra Rafeletou
    • Jenni Viivi Linnea Niemi
    • Francisco Alejandro Lagunas-Rangel
    • Wen Liu
    • Błażej Kudłak
    • Helgi B. Schiöth
    2024 SCIENCE OF THE TOTAL ENVIRONMENT

    Substances that can absorb sunlight and harmful UV radiation such as organic UV filters are widely used in cosmetics and other personal care products. Since humans use a wide variety of chemicals for multiple purposes it is common for UV filters to co-occur with other substances either in human originating specimens or in the environment. There is increasing interest in understanding such co-occurrence in form of potential synergy, antagonist, or additive effects of biological systems. This review focuses on the collection of data about the simultaneous occurrence of UV filters oxybenzone (OXYB), ethylexyl-methoxycinnamate (EMC) and 4-methylbenzylidene camphor (4-MBC) as well as other classes of chemicals (such as pesticides, bisphenols, and parabens) to understand better any such interactions considering synergy, additive effect and antagonism. Our analysis identified >20 different confirmed synergies in 11 papers involving 16 compounds.

  • The Fuzzy Analysis of Western Windfarm Transportation Safety
    • Marek Moszyński
    • Jhu Hong-Yi
    • Sheng-Long Kao
    • Sin-Der Lee
    • Lo Tzu-Chieh
    2024 Pełny tekst

    The previously completed route planning research of Navigational Transportation Safety in the Taiwan Western wind farm analyzed delves into the expansion of sustainable wind energy and navigation safety together along the Taiwan Western for confronting the challenge of balancing resource coexistence and displacement. Previous studies primarily focused on route planning and vessel traffic density which developed the necessary comprehensive analysis. Therefore, this study examines the area of Taiwan’s western Offshore Wind Farm (OWF) environmental issues to develop a Precautionary Area (PA) and RADAR handoff site location analysis. This model analysis introduces a new PA concept that considers navigational and ecological safety, and also wind and hydrological resources, and offshore RADAR handoff mechanisms. Automatic Identification System (AIS) and wind farm RADAR surveillance data are used for converting and analyzing information through the Marine Geographic Information System (MGIS) and Fuzzy Method (FM)that proposed an alternative PA and RADAR site location selection that could facilitate Taiwan’s Green Energy and Navigational Safety

  • The GovTech Challenge – GovTech and Public Value Creation
    • Nitesh Bharosa
    • Tomasz Janowski
    2024 Pełny tekst

    Governments struggle to harness emerging technologies to improve public services, address social needs, and produce public value. In response, we see a rise in GovTech startups and other non-government actors trying to bring innovative solutions to governments. While some public agencies welcome such help, many are reluctant to rely on external organizations to provide digital identities, data wallets and AI-based services to citizens, businesses, and the government itself. Many also fear engaging a dynamic ecosystem of small non-government actors working together and gaining more experience in the process. Consequently, the GovTech supply and demand are misaligned with each other and the public value imperative. Public tendering may help but does not protect against vendor lock-in and innovation-blocking. Co-creation of public and private solutions may be technically possible but may face institutional void, calling for trust frameworks, steward-ownership, ecosystem building or other alternative instruments. This paper presents a research challenge to examine GovTech evidence, learn about applicable theories, methods and knowledge gaps, and formulate theoretically and empirically well-grounded recommendations on GovTech and public value creation. It also outlines the response to the challenge: organizing a dg.o 2024 workshop and developing a special issue of Government Information Quarterly (GIQ).

  • “The Guardians of the Truth”: Journalists’ Resistance to the Algorithmization of Journalism
    • Jan Kreft
    • Monika Boguszewicz-kreft
    • Mariana Fydrych
    2024 Pełny tekst ETHOS. KWARTALNIK INSTYTUTU JANA PAWŁA II KUL

    Regardless of the term used, be it “robot journalism,” “automated journalism,” “algorithmic journalism” or “machine-written journalism,” the process of automatic content creation and distribution is progressing in the newsrooms. Meanwhile, exercising control over the creation and distribution of news is considered a fundamental element of journalists’ professional identity. The article presents the results of research on the perception of algorithmic content creation conducted among journalists in the context of their professional values and identity. The research was conducted with a qualitative method using a semi-structured interview technique with 18 journalists employed in leading Polish media. According to the study, algorithmic journalism is perceived by journalists primarily in the context of posing a threat to the fundamental journalistic principle of providing true information: what they bring to the fore is the potential for creating and spreading fake news. The respondents, who defended their journalistic professional identity, compared the disadvantages of algorithmic journalism with the unique competences of “human” journalists, perceiving the latter as advocates of concern for the quality standards of social discourse and as “guardians of the truth”.

  • The Impact of Different Drying Methods on the Metabolomic and Lipidomic Profiles of Arthrospira platensis
    • Marika Mróz
    • Karol Parchem
    • Joanna Jóźwik
    • M. Rosário Domingues
    • Barbara Kusznierewicz
    2024 Pełny tekst MOLECULES

    Drying is an inseparable part of industrial microalgae production. In this work, the impacts of eight different drying methods on the metabolome and lipidome of Arthrospira platensis were investigated. The studied drying methods were freeze drying (FD), sun drying (SD), air drying at 40 and 75 °C (AD′ and AD″), infrared drying at 40 and 75 °C (IRD′ and IRD″), and vacuum drying at 40 and 75 °C (VD′ and VD″). Results gathered by reversed-phase liquid chromatography separation coupled with high-resolution tandem mass spectrometry with electrospray ionization (RP-LC-ESI-Orbitrap HRMS/MS) analysis allowed researchers to identify a total of 316 metabolites (including lipids) in aqueous and ethanolic extracts. The compounds identified in ethanolic extracts were mainly lipids, such as neutral and polar lipids, chlorophylls and carotenoids, while the compounds identified in the aqueous extracts were mainly amino acids and dipeptides. Among the identified compounds, products of enzymatic and chemical degradation, such as pyropheophytins, monoacylglycerols and lysophosphatidylcholines were also identified and their amounts depended on the drying method. The results showed that except for FD method, recognized as a control, the most protective method was AD′. Contrary to this, VD′ and VD″, under the conditions used, promoted the most intense degradation of valuable metabolites.

  • The Impact of Drying Conditions on the Surface Color Changes of Pine Wood
    • Aleksandra Suchta
    • Jacek Barański
    • Tatiana Vilkovská
    • Ivan Klement
    • Peter Vilkovský
    2024 Pełny tekst BIORESOURCES

    The article presents the impact of drying process and selected parameters on the color changes on the surface of pine wood (Pinus sylvestris L.). Three predetermined process conditions (modes), mild, normal, and intensive, were investigated. The experiments were conducted using a semi-industrial scale dryer designed at the Gdańsk University of Technology with a loading capacity of 0.55 m3. The drying process was applied to pine wood grown in the northern part of Pomeranian region in Poland. The specimens were selected taking into consideration the radial angle of the growth rings. During each drying mode, 25 pieces of wood with dimensions (thickness, width, length) of 0.03 m, 0.2 m, and 1.5 m, respectively, were dried. The total color change (ΔE) after drying process and color saturation (h*) before and after drying processes of the wood surface was determined using the normalized CIELAB methods. The obtained results indicated that the color change of the pine wood surface increased simultaneously with the intensification of the drying process. However, the normalized wood quality after drying under intensive drying process conditions remained within the standard limits. The application of intensive drying process conditions remarkably changes the surface color of the obtained material, while remarkably reducing the drying process duration.

  • The Impact of Foreign Accents on the Performance of Whisper Family Models Using Medical Speech in Polish
    • Szymon Zaporowski
    2024 Pełny tekst

    The article presents preliminary experiments investigating the impact of accent on the performance of the Whisper automatic speech recognition (ASR) system, specifically for the Polish language and medical data. The literature review revealed a scarcity of studies on the influence of accents on speech recognition systems in Polish, especially concerning medical terminology. The experiments involved voice cloning of selected individuals and adding prosodic contours with Russian and German accents, followed by transcription of these samples using all available models from the Whisper family and comparison with the original transcription. The results of these initial experiments suggest that the Whisper model struggles with foreign accents in the context of Polish language and medical terminology. This highlights the need for further research aimed at improving ASR systems for foreign accents and medical terminology.

  • The impact of global value chains on wages, employment, and productivity: a survey of theoretical approaches
    • Sabina Szymczak
    2024 Pełny tekst Journal for Labour Market Research

    This study presents a systematic literature review to provide a collection of theories explaining the impact of global value chains (GVCs) on labour market outcomes. Due to the complex nature of GVCs and the interconnectedness of wages, employment, and productivity, many direct and indirect effects are at play. To ensure a transparent and systematic flow of the review process, I follow the PRISMA guide. Eventually, 36 records out of 1221 results from Scopus database were selected. This review may be useful for theorists, empirical economists, and policy makers as an overview of theoretical developments and convenient map of potential outcomes expected from involvement in GVCs. It identifies and systematizes a number of effects existing in the literature under various names. The results show that the predictions from the theory are ambiguous. The positive effects which may emerge regardless the characteristics of the GVC are the productivity-enhancing effect and the cross-effect, especially important considering growing servicification of manufacturing. Here lies the critical role of the state and policies to assure that the losses will not exceed the gains in the aggregate terms. One of the main factors shaping the outcome is the power distribution among the GVC’s firms. Additionally, this paper shows the shortcomings of the existing theories. Less aggregated levels of analysis could be a great input to the discussion, as well as addressing different GVCs’ dimensions and types of organisation. The understanding of relation between GVC position and labour market is especially worth exploration as the existing evidence adopt different and even contradicting perspectives on the definition of upgrading the GVC position.

  • The impact of graphene on the electrochemical performance of BiMeVOx catalysts in water splitting
    • Patrycja Grabowska
    • Mariusz Szkoda
    • Malgorzata Skorupska
    • Marta Gajewska
    • Anna Ilnicka
    2024 INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

    The development of efficient catalysts for electrochemical water splitting has become a significant contemporary challenge. Transition metal oxides, due to their unique electrochemical properties, have emerged as promising candidates. Among these, a group of BiMeVOx-based compounds shows particular potential for practical applications in hydrogen and oxygen evolution reactions. However, improvement is still necessary to achieve stable operation of these catalysts in green hydrogen generation. With this is mind, in this study we synthesize BiMeVOx materials with graphene addition using a simple annealing in a tube furnace and investigate their electrochemical properties in HER and OER. After incorporating different metals into the BiMeVOx structure, we observed variations in electrochemical properties; materials with the addition of molybdenum and cobalt (BiMoVOx and BiCoVOx) outperformed materials containing zirconium and cerium (BiZrVOx and BiCeVOx). The BiMoVOx/C catalyst showed excellent HER performance with an overpotential of 432 mV at 10 mA/cm2 and a Tafel slope of 76 mV dec⁻1, while BiCoVOx/C exhibited superior OER activity with a Tafel slope of 100 mV dec⁻1, lower than that of commercial IrO₂. The addition of graphene improved the conductivity and overall activity of the catalysts. These findings indicate that metal doping and graphene incorporation are effective strategies for enhancing the performance of BiMeVOx-based materials in water splitting applications.

  • The Impact of LY487379 or CDPPB on eNOS Expression in the Mouse Brain and the Effect of Joint Administration of Compounds with NO• Releasers on MK-801- or Scopolamine-Driven Cognitive Dysfunction in Mice
    • Agata Płoska
    • Anna Siekierzycka
    • Paulina Cieślik
    • Lawrence W. Dobrucki
    • Leszek Kalinowski
    • Joanna M. Wierońska
    2024 Pełny tekst MOLECULES

    The role of endothelial nitric oxide synthase (eNOS) in the regulation of a variety of biological processes is well established, and its dysfunction contributes to brain pathologies, including schizophrenia or Alzheimer’s disease (AD). Positive allosteric modulators (PAMs) of metabotropic glutamate (mGlu) receptors were shown to be effective procognitive compounds, but little is known about their impact on eNOS expression and stability. Here, we investigated the influence of the acute and chronic administration of LY487379 or CDPPB (mGlu2 and mGlu5 PAMs), on eNOS expression in the mouse brain and the effect of the joint administration of the ligands with nitric oxide (NO) releasers, spermineNONOate or DETANONOate, in different combinations of doses, on MK-801- or scopolamine-induced amnesia in the novel object recognition (NOR) test. Our results indicate that both compounds provoked eNOS monomer formation, and CDPPB at a dose of 5 mg/kg exaggerated the effect of MK-801 or scopolamine. The coadministration of spermineNONOate or DETANONOate enhanced the antiamnesic effect of CDPPB or LY487379. The best activity was observed for ineffective or moderate dose combinations. The results indicate that treatment with mGluR2 and mGluR5 PAMs may be burdened with the risk of promoting eNOS uncoupling through the induction of dimer dissociation. Administration of the lowest possible doses of the compounds with NO• donors, which themselves have procognitive efficacy, may be proposed for the treatment of schizophrenia or AD.

  • The influence of azide and imidazole on the properties of Mn- and Cd-based networks: conductivity and nonlinear phenomena
    • Monika Trzebiatowska
    • Dorota A. Kowalska
    • Agnieszka Ciżman
    • Natalia Wójcik
    • Ryszard Barczyński
    • Adam Pikul
    • Jan K. Zaręba
    • Marcin Palewicz
    • Tomasz Piasecki
    • Krystian Roleder
    • Marek Gusowski
    • Mirosław Mączka
    2024 Journal of Materials Chemistry C

    We report a study on a family of four new Mn- and Cd-azide-imidazolate-based compounds with various crystal architectures. Notably, three of these compounds display noncentrosymmetric crystal arrangements at room temperature, a rare phenomenon in hybrid organic–inorganic materials. Both nonlinear optical (NLO) and electrical phenomena in these compounds are observed. The NLO processes include second and third harmonic generation, while the electrical nonlinear phenomena include the presence of polarization and a coercive field in the capacitance measurements (1–2 μC cm−2), and a piezoelectricity with ca. d33 = 0.2 × 10−12 m V−1 coefficient. Additionally, the presence of the second and third harmonics is detected in DC conductivity measurements. The phase transition (PT) present in Mn-based compounds at ca. 370 K is confirmed by DSC, X-ray diffraction, Raman spectroscopy, dielectric, DC conductivity and capacitance measurements. The PT is triggered by the motions of imidazole molecules around a nitrogen-metal bond with minor adjustment of azide bridges in response to this motion as derived from the X-ray diffraction and spectroscopic data. Mn-analogues also feature antiferromagnetic order. Both Cd- and Mn-imidazolate-azides exhibit a conductivity, with a mixed electron/proton hopping transport mechanism, in the case of Cd- similar to those of classic semiconductors.

  • The influence of bio-based monomers on the structure and thermal properties of polyurethanes
    • Janusz Datta
    • Joanna Brzoska
    • Hynek Benes
    • Václav Pokorný
    • Rafał Konefał
    2024 Scientific Reports

    Most polyurethanes (PU) are currently produced through the polyaddition reaction of polyisocyanates with polyols and chain extenders, using components of petrochemical origin. From an environmental and geopolitical point of view, and with regard to the problems of oil supply and processing, the replacement of petrochemical PU raw materials with renewable resources is highly desirable. It is also one of the principles of sustainable development and an important challenge for chemical companies and market competitiveness. Current research studies focus mainly on the use of bio-based polyols for PUs, while other PU components, in particular polyisocyanates, remain of petrochemical origin. In this work, a series of PUs have been synthesized by polyaddition reactions of different types of renewable polyols and bio-based polyisocyanates. The effects of the bio-derived components on the structure, thermal stability and phase transformations of the PU were studied using FTIR and NMR spectroscopy, SWAXS, TGA, DSC, DMTA and TGA-FTIR. A full conversion of the bio-based monomers was achieved in all cases, indicating good compatibility and reactivity of all bio-based components. It was observed that bio-based PU exhibited a lower degree of phase separation and slightly lower thermal stability compared to PUs from petrochemical monomers.

  • The Influence of Different Hydrothermal Processes Used in the Preparation of Brussels Sprouts on the Availability of Glucosinolates to Humans
    • Anna Sadowska-Rociek
    • Joanna Doniec
    • Barbara Kusznierewicz
    • Tomasz Dera
    • Agnieszka Filipiak-Florkiewicz
    • Adam Florkiewicz
    2024 Foods

    Cruciferous vegetables represent a valuable source of bioactive compounds. However, there is currently a deficiency of information regarding the extent to which these compounds remain bioaccessible to the body following thermal treatment and digestion processes within the digestive tract. Accordingly, the aim of this study was to evaluate the impact of heat treatment and in vitro digestion on the level of selected bioactive compounds in Brussels sprouts. The Brussels sprouts samples were subjected to a range of thermal processing techniques, which were then followed by a simulated in vitro digestion. The investigated compounds were analyzed using UV-Vis spectrometry and liquid chromatography coupled with mass spectrometry (LC-MS). The findings revealed that the sous-vide method of cooking Brussels sprouts resulted in significantly higher losses of glucosinolates (GLS) in comparison to conventional cooking methods. No significant differences were observed with regard to isothiocyanates and indoles. The analysis of GLS following digestion revealed that the process was more effective after sous vide and traditional cooking, and slightly less effective after steam cooking. With regard to individual compounds, glucoraphanin (GRA), glucoraphenin (GIV), and gluconasturtiin (GNS) were found to be completely degraded, whereas methoxyglucobrassicin (metGBS) was the most resistant to digestion in both the sous vide and steamed Brussels sprouts. The results indicated that the process of simulating digestion had no significant impact on isothiocyanates and indoles. This suggests that, if present in the heat-treated samples, these compounds remained stable during the in vitro digestion procedure.

  • The Influence of Global Corrosion Degradation on Localized Damage Detection Using Guided Waves
    • Beata Zima
    • Emil Roch
    • Jochen Moll
    2024

    This paper presents the results of a numerical analysis of the influence of corrosion degradation of metal plates on the wave propagation phenomenon. There are several different corrosion types, but general and pitting corrosion are the most common. General corrosion is more or less uniformly distributed over the entire exposed surface of the metal while pitting corrosion takes the form of localized cracks. Because the general corrosion is related to thickness reduction and in consequence, wave propagation velocity, this study is focused on the influence of the variable thickness of corroded plate described by the statistical descriptors (average thickness, standard deviation and coefficient of variation) on the uncertainty of localized damage detection based on the algorithms incorporating velocity of the guided wave. Numerical simulations were conducted for corroded plates with localized cut-through damage. The irregular surface of the plates was modeled using random fields. In this study, the plates varying in degree of degradation (DoD) as well as in geometry of the surface have been analyzed. Such an approach allowed for observing the effects of both thickness reduction and the exact geometry of corroded plates on damage detection and localization. The common approach based on delay and sum algorithm to detect and localize damage has been applied here.

  • The Influence of Impact Velocity on Stresses and Failure of S355j2 Steel Under Slurry Erosion Conditions
    • Dominika Zakrzewska
    • Marta H. Buszko
    2024 Pełny tekst Advances in Science and Technology Research Journal

    The purpose of this work was to determine the essence of the influence of the impact velocity (5, 7, and 9 m/s) on Hertzian stresses and the erosion mechanism of ferritic-pearlitic S355J2 steel. The investigations were carried out using a slurry pot tester. S355J2 steel showed a strong sensitivity to changes in impact velocity. A significant increase in erosion rate was observed at a velocity of 9 m/s. This increase was 5-fold and over 15-fold compared to velocities of 7 m/s and 5 m/s, respectively. The study of Hertzian stress is crucial in erosion research because it helps understand how impact energy is absorbed by the eroded material and the mechanisms that cause surfacewear. A linear increase in mean contact pressure and maximum shear stress was observed with increasing impactvelocity. The mean contact pressure increased from 4.3 GPa to 5.5 GPa and the maximum shear stress increasedfrom 2.0 GPa to 2.5 GPa. The kinetic energy of the solid particles that hits the eroded steel is distributed in the con-tact area, which leads to various deformations and wear mechanisms. The primary type of deformation was fatiguedegradation of the surface layers of the eroded steel. The high kinetic energy of solid particles contributed to theformation of plastic deformations and strongly deformed steel flakes. Higher impact velocities generally result ingreater forces and contact stresses on the material surface. This led to the intensification of plastic deformation inthe contact areas and increased the Hertzian stresses.

  • The influence of the geographic positioning system error on the quality of ship magnetic signature reproduction based on measurements in sea conditions
    • Jarosław Tarnawski
    • Krystian Buszman
    • Mirosław Wołoszyn
    • Bartosz Puchalski
    2024 Pełny tekst MEASUREMENT

    In previous studies, the authors performed the magnetic signature reconstruction of the marine ship Zodiak as part of the measurement campaign focused on recording magnetic data and the relative position of a ship during its passage over a magnetometer immersed on the testing ground. A high degree of representation of the magnetic signature was obtained. However, the recorded measurement data revealed new patterns of the multidipole model behavior that were not observed in the synthetic data based analyzes. It was assumed that the main factor influencing the abovementioned behavior of the model is the error in determining the geographical position of the ship in relation to the magnetometer. Therefore, another research was carried out to determine the relative position of the ship and the measurement device in sea conditions, in the area of the test site used in the previous study. For this purpose, two different classes of GPS receivers were used. The first receiver was the same as that used to determine the position of Zodiak in the previous measurement campaign, while the second receiver, treated as a reference, was a top-class geodetic receiver. The difference in indications between these two receivers gave a picture of the scale of errors in the data recorded during the previous measurement campaign. These errors are used in the article to analyze the effect of inaccuracies in determining the ship position on the quality of magnetic signature reproduction. Two types of signature reproduction error were introduced – the error based only on the data collected from the ship’s paths, and the error in the entire area of magnetic anomaly. The model of Zodiak was used to determine the value of the magnetic flux outside the paths. Profiles of differences in indications of GPS receivers at sea which were obtained from actual measurements were used to analyze the errors in determining the ship position. A measurable result of the work reported in the article is the map of the loss of quality of magnetic signature reproduction as a function of the ship position determination error, which can indicate the range of applicability of the model and the described method.

  • The influence of α,ω-diols and SiO2 particles on CO2 absorption and NH3 escaping during carbon dioxide capture in ammonia solutions
    • Temesgen Amibo
    • Donata Konopacka-Łyskawa
    2024 Pełny tekst Journal of CO2 Utilization

    Ammonia solutions are widely used solvents for CO2 capture. However, a significant disadvantage of these solvents is secondary pollution of the purified gas stream by desorbed ammonia. In this work, α,ω-diols, and colloidal silica have been proposed to reduce this undesired effect. Ammonia solutions with the addition of ethylene glycol (EG), 1,3-propanediol (PRD), 1,4-butanediol (BUD), 1,5-pentanediol (PED), or 1,6-hexanediol (HED) and ammonia solution with the addition of diol and colloidal SiO2 were tested. The concentration of CO2 and NH3 in the exhaust gas was continuously measured during the experiments. Based on the recorded measurements, the number of moles of CO2 absorbed and the number of moles of NH3 lost were calculated. Mass transfer coefficients for CO2 absorption and NH3 desorption were also determined. The studies showed that CO2 absorption occurred faster in ammonia solutions with EG, PRD, BUD, and HED, and the CO2 loading was higher than in pure NH3 solution. The most effective additive improving CO2 absorption was BUD, followed by HED. SiO2 particles improved slightly the absorption efficiency in most of the tested diol solutions. All diols used inhibited the escape of ammonia, with PED having the most effective effect. However, adding silica particles effectively inhibited ammonia escape in all tested systems.

  • The Input of Nanoclays to the Synergistic Flammability Reduction in Flexible Foamed Polyurethane/Ground Tire Rubber Composites
    • Aleksander Hejna
    • Paulina Kosmela
    • Adam Olszewski
    • Wiktoria Żukowska
    2024 Materials

    Currently, postulated trends and law regulations tend to direct polymer technology toward sustainability and environmentally friendly solutions. These approaches are expressed by keeping materials in a loop aimed at the circular economy and by reducing the environmental burdens related to the production and use of polymers and polymer-based materials. The application of recycled or waste-based materials often deals efficiently with the first issue but at the expense of the final products’ performance, which requires various additives, often synthetic and petroleum-based, with limited sustainability. Therefore, a significant portion of research is often required to address the drawbacks induced by the application of secondary raw materials. Herein, the presented study aimed to investigate the fire performance of polymer composites containing highly flammable matrix polyurethane (PU) foam and filler ground tire rubber (GTR) originating from car tire recycling. Due to the nature of both phases and potential applications in the construction and building or automotive sectors, the flammability of these composites should be reduced. Nevertheless, this issue has hardly been analyzed in literature and dominantly in our previous works. Herein, the presented work provided the next step and investigated the input of nanoclays to the synergistic flammability reduction in flexible, foamed PU/GTR composites. Hybrid compositions of organophosphorus FRs with expandable graphite (EG) in varying proportions and with the addition of surface-modified nanoclays were examined. Changes in the parameters obtained during cone calorimeter tests were determined, discussed, and evaluated with the fire performance index and flame retardancy index, two parameters whose goal is to quantify the overall fire performance of polymer-based materials.

  • The Interplay between Endogenous and Foodborne Pro-Oxidants and Antioxidants in Shaping Redox Homeostasis
    • Patrycja Jakubek
    • Karol Parchem
    • Mariusz R. Wieckowski
    • Agnieszka Bartoszek-Pączkowska
    2024 INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES

    Oxidative stress has been known about in biological sciences for several decades; however, the understanding of this concept has evolved greatly since its foundation. Over the past years, reactive oxygen species, once viewed as solely deleterious, have become recognized as intrinsic components of life. In contrast, antioxidants, initially believed to be cure-all remedies, have failed to prove their efficacy in clinical trials. Fortunately, research on the health-promoting properties of antioxidants has been ongoing. Subsequent years showed that the former assumption that all antioxidants acted similarly was greatly oversimplified. Redox-active compounds differ in their chemical structures, electrochemical properties, mechanisms of action, and bioavailability; therefore, their efficacy in protecting against oxidative stress also varies. In this review, we discuss the changing perception of oxidative stress and its sources, emphasizing everyday-life exposures, particularly those of dietary origin. Finally, we posit that a better understanding of the physicochemical properties and biological outcomes of antioxidants is crucial to fully utilize their beneficial impact on health.

  • The KLC Cultures Synergy for Organizational Agility. Trust, Risk-Taking Attitude, and Critical Thinking as Moderators
    • Wioleta Kucharska
    • Maciej Kucharski
    • Tomasz Balcerowski
    2024 Pełny tekst

    Organizational agility is visible in organizational change adaptability, and it is based on the development of dynamic capabilities, strategic sensitivity of leaders, accuracy and timing of decision-making, learning aptitude, flexibility in thinking and acting, and smooth resource flow across organizations, including the knowledge resource. In such a context, this study aimed to expose how the knowledge, learning, and collaboration cultures approach (KLC) supports organizational agility when this relation is moderated by mutual trust among employees, risk-taking attitude, and critical thinking abilities. Based on the sample composed of 640 Polish knowledge workers and data analyzed with the structural equation modeling method (SEM), this study's results proved that the KLC culture synergy supports organizational agility building and that the mistakes acceptance component of learning culture is critical. Moreover, trust among workmates, risk-taking readiness, and critical thinking skills are significant mediators. The key novelty was exposed through the negative influence of a risk-taking attitude (uncertainty acceptance) on agility. Precisely, the lack of risk acceptance or, reversely, the risk-avoidance attitude supports agility. This is because agility, understood as smooth adaptability, is the effect of efficient risk management. Thanks to risk management and critical thinking, the negative impact of inaction risks can often be seen as higher than the risks of very innovative actions. The KLC approach, critical thinking, and trust among workmates support the smooth selection of risks that must be taken in today's dynamic business. Risk is inevitable. So, from this point, the essence of agility is the ability to smoothly and wisely select among risks that should be taken or avoided. In summary, agility can be considered to be the smooth selection of acceptable risks

  • The KLC Cultures' Synergy Power, Trust, and Tacit Knowledge for Organizational Intelligence
    • Wioleta Kucharska
    • Denise A. D. Bedford
    2024 Pełny tekst Electronic Journal of Knowledge Management

    This paper examines the impact of knowledge, learning, and collaboration culturessynergy (the KLC approach) on organizational adaptability. The SEM analysis method was applied to verify the critical assumption of this paper: that the KLC approach and trust support knowledge-sharing processes (tacit and explicit) and are critical for organizational intelligence activation.Specifically, the empirical evidence, based on a 640-case sample composed of Polish knowledge workers, revealedthat knowledge sharing, organizational intelligence, and innovativeness are vital benefits of the KLC cultures’synergy. It also highlighted that trust among workmates is critical to sustaining tacit knowledge sharing in an organization. Tacit knowledge, which is knowledge that is difficult to transfer to another person by means of writing it down or verbalizing it, is clearly identified as a key component of change adaptability, which is viewed as a measure oforganizational intelligence. Moreover, the acceptance of mistakesas a learning source -a learning culturecomponentthat supports trial-error learning,was found to betremendous for knowledge-sharing processes, organizational intelligence (change adaptability),and innovativeness. Thisstudyproved that knowledge sharing, organizational intelligence, and innovativeness are vitalbenefits of the synergy that offers the KLC cultures. Trust strengthens this effect. So, to gain these benefits, knowledge-driven organizations should employ trusted managers who trust others and, in addition to their professional credentials, exhibit strong habits of respecting knowledge, learning, and collaboration.

  • The landscape in the informal education of the youngest
    • Marta Koperska-Kośmicka
    2024 Pełny tekst Journal of Geography, Politics and Society

    The European Landscape Convention, adopted in 2000, aims to promote the protection, management and planning of landscapes and to organise cooperation on landscape-related issues. Countries that ratified the Convention undertook to introduce activities that would promote public education on the subject. In Poland, the Ministry of Education has identified schools as the place to implement these priorities. In the core curriculum of general education for primary schools, «creating opportunities to learn about the components of the landscape» was prescribed as the primary objective of the subject of nature. Although the school should play a leading role in the implementation of these tasks, even in its most elaborate form it is unable to meet all the needs. It should be complemented by non-formal education, which goes beyond the school curriculum and is a kind of its extension. This article is an attempt to present and evaluate the author’s educational project dealing with the topic of cultural landscape at the regional level.

  • THE METHODS OF TEACHING / LEARNING STRUCTURAL MECHANICS
    • Marek Skowronek
    2024 Pełny tekst

    Structural mechanics is a key issue to study for engineers. A high rank and high social responsibility profession requires both a high graded and intuitive approach. The evolution of learning / teaching methodology follows the novel technical achievements of every decade. The aim remains the same: to produce a professional to perform advanced relevant analysis and safe, optimal structural design

  • The pulse width modulation strategy for a five-phase three-level NPC voltage source inverter with DC-link voltage balancing ability
    • Dmytro Kondratenko
    2024 Pełny tekst

    The doctoral dissertation is all about the development of the space vector modulation algorithm for controlling the generation of output voltage vectors in a three-level, five-phase NPC inverter. The developed algorithm can be used to control five-phase motors, where it will be possible to increase the motor torque by 15%; by appropriate injection of 3rd harmonic current. The proposed control approach also opens up the possibility of independent control of two electric motors, supplied from a single inverter. The critical issues that need to be solved when creating pulse-width modulation algorithms for multiphase, three-level inverters are the need to simultaneously balance the input splitting DC-link capacitor voltages and ensure correct generation of many independent voltage vectors. This scenario is also applicable to the case when the DC-link voltages are of different values. The proposed solution paves way for independent syntheses of output voltages with minimum number of active switches’ transitions; while allowing for appropriate voltage distribution on the DC-link capacitors.

  • The relative cup-length in local Morse cohomology
    • Thomas O. Rot
    • Maciej Starostka
    • Nils Waterstraat
    2024 Topological Methods in Nonlinear Analysis

    Local Morse cohomology associates cohomology groups to isolating neighborhoods of gradient flows of Morse functions on (generally non-compact) Riemannian manifolds M. We show that local Morse cohomology is a module over the cohomology of the isolating neighborhood, which allows us to define a cup-length relative to the cohomology of the isolating neighborhood that gives a lower bound on the number of critical points of functions on M that are not necessarily Morse. Finally, we illustrate by an example that this lower bound can indeed be stronger than the lower bound given by the absolute cup-length.

  • THE REPRESENTATION PROBLEM FOR A DIFFUSION EQUATION AND FRACTAL R-L LADDER NETWORKS
    • Jacky Cresson
    • Anna Szafrańska
    2024 Proceedings of the Institute of Mathematics and Mechanics

    The representation problem is to prove that a discretization in space of the Fourier transform of a diffusion equation with a constant diffusion coefficient can be realized explicitly by an infinite fractal R-L ladder networks. We prove a rigidity theorem: a solution to the representation problem exists if and only if the space discretization is a geometric space scale and the fractal ladder networks is a Oustaloup one. In this case, the resistance and inertance of the ladder are explicitly determined up to a constant.

  • The role of governance to support smart community development: a systematic literature review
    • Magdalena Ciesielska
    • Gabriela Viale Pereira
    2024 Pełny tekst

    This paper studies the interaction between the smart community and smart governance concepts to elaborate on the role of governance to support local governments in developing smart communities’ strategies and solutions. We perform a systematic literature review to analyse how the concept of smart community has advanced in terms of its definitions, context, benefits, challenges, and enablers and propose a unified term with a focus on the governance aspects. The review highlights that some conceptualizations of smart communities have a more technical perspective that evolved towards a socio-technical concept, being information and communication technologies a mediator to behaviour change and a tool to improve decision-making and citizen-centricity, as well as promoting social governance.

  • The role of microbial coagulants on the physicochemical, proteolysis, microstructure and sensory properties of low-fat Edam cheese manufactured from ultrafiltered buffalo milk
    • Safaa A.M. El-Aidie
    • Roberto Castro Munoz
    • Basim Abu-Jdayil
    • Samia M. El-Dieb
    2024 Pełny tekst INTERNATIONAL DAIRY JOURNAL

    This work investigates the influence of using microbial coagulants, including Rhizomucor miehei (MCR) protease and Cryphonectria parasitica (MCC) protease, on the quality characteristics of low-fat Edam cheese made from ultrafiltered buffalo milk (LFUE). Concurrently, a benchmark with calf rennet (CR) has been also performed. Throughout a 90-day ripening period, the cheeses were assessed for their physicochemical features, proteolysis, texture, free amino acid and free fatty acid content, microstructure, and sensory attributes. The study revealed that both microbial coagulants had no significant impact on the physicochemical composition and firmness of the cheeses while slightly affected the free fatty acids. Cheeses made with microbial coagulants displayed higher proteolysis, with MCR and MCC cheeses exhibiting greater levels of water-soluble nitrogen and 12% trichloroacetic acid-soluble nitrogen than CR cheese. MCR and MCC cheeses exhibited more extensive breakdown of αs- and β-caseins, as indicated by the SDS-PAGE electrophoretogram, compared to CR cheese during ripening. As for the proteolytic activity, the microbial coagulant contributed to shaping the free amino acid content, microstructure, and sensory qualities of the cheeses. Notably, MCC cheese outperformed MCR or CR cheeses in terms of free amino acid levels. MCR and MCC cheeses resulted in smooth microstructures with uniform protein networks as observed by microscopy, while CR cheese displayed rough, granular surfaces. With the highest scores for appearance, body, texture, and flavor, MCC cheese demonstrated superior sensory properties compared with MCR and CR cheeses.

  • The role of resilience in explaining hotel growth: A fuzzy-set QCA approach
    • Diana Dryglas
    • Anna Lis
    • Marcin Suder
    2024 Pełny tekst Journal of Entrepreneurship, Management and Innovation

    Purpose: Due to the detrimental effects of the recent pandemic on the hotel sector, hotel resilience research and its impact on hotel recovery have received lots of academic attention. However, a sustainable perspective on hotel resilience, as an approach for investigating its impact on long-term hotel growth, has been largely overlooked in the hospitality resilience literature. Therefore, this paper aims to address the research gap by identifying the configuration of factors that constitute sustainable hotel resilience leading to the growth of selected hotels operating in Poland. Methodology: Data for analysis were obtained from surveys conducted with the participation of 120 managers of one- and two-star hotels. To achieve the goal, a fuzzy-set qualitative comparative analysis (fsQCA) was chosen, which belongs to the group of configurational analysis methods. Findings: Due to the asymmetric nature of the method, the analysis reveals configurations both of factors leading to high hotel growth and those leading to low growth. In both cases, two such factor configurations were obtained. For high levels of hotel growth, it was found that maintaining a high level of three factors simultaneously, namely employee resilience, CSR activities and leadership resilience or CSR activities, team resilience and leadership resilience, provided sufficient conditions. On the other hand, for low levels of growth, fsQCA indicated sufficient conditions in the form of a low level of CSR activities and leadership resilience or a low level of employee resilience and team resilience. These findings emphasise the role of combining different factors to improve hotel growth. Implications for theory and practice: The research contributes to the literature on resilience in the hospitality industry by developing a new theoretical perspective on the complex nature of combinations of factors that contribute to sustainable hotel resilience leading to both high and low growth. The research results also provide significant implications for entrepreneurs and managers, indicating the role of different combinations of factors in determining hotel growth. Originality and value: The knowledge regarding sustainable hotel resilience is still insufficient. The study identified the best combinations of factors (both internal and external) that constitute sustainable hotel resilience, which may be vital for hotel growth.

  • The role of the combined nitrogen-sulfur-carbon cycles for efficient performance of anammox-based systems
    • Dominika Derwis
    • Hussein Al-Hazmi
    • Joanna Majtacz
    • Przemysław Kowal
    • Slawomir Ciesielski
    • Jacek Mąkinia
    2024 SCIENCE OF THE TOTAL ENVIRONMENT

    The combined anammox/mixotrophic denitrification process was conducted in two granular sequencing batch reactors (SBRs) during a 200-day operation. Both reactors were fed with synthetic medium, but SBR2 was enriched with additional sulfate (SO4 2 ) which influenced sulfate reduction ammonium oxidation (SRAO) and heterotrophic reduction of SO4 2 by sulfate reducing bacteria. It was hypothesized that the addition of SO4 2 could positively impact the removal rates of N-S-C compounds. A low C/N ratio (0.4–1.6) was maintained to prevent inhibition of anaerobic ammonium oxidizing bacteria (AnAOB), and alternating chemical oxygen demand (COD) on/off conditions were used to regenerate AnAOB during COD-off phases and heterotrophic denitrifiers during COD-on phases. Stoichiometric analysis showed that introducing SO4 2 in SBR2 enhanced the ammonium utili zation rate, which was approximately 10 % higher compared to SBR1 in the final stage of the experiment (25.8 vs. 22.8 mg N/(g VSS⋅h)). The total nitrogen removal efficiencies ranged from 62 % to 99 % in both reactors, with SBR2 consistently exhibiting approximately 4 % higher efficiency than SBR1. In SBR2, the maximum overall SO4 2 utilization efficiency reached 27 % under COD-off conditions, while overall COD utilization was almost complete under COD-on conditions. A strong correlation (R2 =0.98) was observed between SO4 2 production and COD utilization. The key players responsible for N and S transformations in response to SO4 2 addition were Candidatus Brocadia and Chloroflexi - Anaerolineae. This study highlights the potential to enhance the overall efficiency of N-S-C removal by implementing an integrated anammox/mixotrophic denitrification process. The combination of cycles emerges as a sustainable approach for treating wastewater rich in N-S-C compounds.

  • The scope of fiscal decentralisation in EU countries: a comparative analysis
    • Alicja Sekuła
    • Karol Flisikowski
    2024 Pełny tekst EKONOMIA I PRAWO

    Motivation: Decentralization is one of the main challenges in public sector reform. In democratic countries the level of decentralisation in individual countries is not identical. The varying scope of decentralization affects the quality, quick and efficient decision-making by public leaders. Aim: Comparison of the extent of fiscal decentralisation in EU Member States; creation of groups of states with similar levels of decentralisation; identification of characteristics of countries where the average level of decentralisation is similar. Results: As a result of the study 4 clusters were created. The first includes centralized countries (small area, small population, e.g. Malta, Cyprus). The level of decentralization is a little bit higher in federal states and most of the countries that joined the EU in 2004 or later (cluster 2, the most numerous). Larger and more numerous countries are characterized by a higher level of decentralization (cluster 3, e.g. Italy, Poland, France). Clusters 4th is composed of the Nordic countries, i.e. in countries where a welfare state model with an extensive public sector has been implemented. As a result, it was found that the level of decentralization is related to the size of the country, population and political system.

  • The shape of an ROC curve in the evaluation of credit scoring models
    • Błażej Kochański
    2024 Pełny tekst STATISTICS IN TRANSITION

    The AUC, i.e. the area under the receiver operating characteristic (ROC) curve, or its scaled version, the Gini coefficient, are the standard measures of the discriminatory power of credit scoring. Using binormal ROC curve models, we show how the shape of the curves affects the economic benefits of using scoring models with the same AUC. Based on the results, we propose that the shape parameter of the fitted ROC curve is reported alongside its AUC/Gini whenever the quality of a scorecard is discussed.

  • The Smith-Watson-Topper parameter and fracture surface topography relationship for additively manufactured 18Ni300 steel subjected to uniaxial variable-amplitude loading
    • Wojciech Macek
    • Zbigniew Marciniak
    • Grzegorz Lesiuk
    • Przemysław Podulka
    • Cho-pei Jiang
    2024 Pełny tekst THEORETICAL AND APPLIED FRACTURE MECHANICS

    In this paper, the association between Smith-Watson-Topper (SWT) parameter and fracture surface topography is studied in additively manufactured maraging steel exposed to variable-amplitude fatigue loading. The post-failure fracture surfaces were examined using a non-contact 3D surface topography measuring system and the entire fracture surface method. The focal point is on the correspondence between fatigue characteristics, articulate by the SWT parameter, and the fracture surface topography features, represented by areal, volume, and fractal dimension parameters. A fatigue life prediction model based on SWT and fracture surface topography factors is proposed. The presented model expresses good compliance with fatigue test results. This model can be useful for post-mortem analysis of engineering elements under variable-amplitude loading fatigue, especially for materials produced by additive manufacturing (AM).

  • The study on the appearance of deformation defects in the yacht lamination process using an AI algorithm and expert knowledge
    • Paweł Szalewski
    • Tacjana Niksa-Rynkiewicz
    • Mariusz Deja
    2024 Pełny tekst Scientific Reports

    This article describes the application of the A-priori algorithm for defining the rule-based relationships between individual defects caused during the lamination process, affecting the deformation defect of the yacht shell. The data from 542 yachts were collected and evaluated. For the proper development of the algorithm, a technological process of the yacht lamination supported by expert decisions was described. The laminating technology is a complex process of a sequential application of individual laminates according to a special strategy. The A-priori algorithm allowed for obtaining the set of association rules defining the relationships between the defects resulting from the lamination process and influencing the deformation defect of the yacht shell, which is one of the most common errors in yacht production. The obtained aggregated rules were compared with the expert knowledge of the employees of the production, quality control, mould regeneration, and technology departments of the yacht yard. The use of the proposed A-priori algorithm allowed for the generation of relationship rules consistent with the general opinion of experts. Associative rules additionally took into account detailed causes of a specific error, which were not always noticed by employees of specific departments. The assessment of the lamination process using an artificial intelligence algorithm turned out to be more objective, which made it possible to gradually reduce the total number of errors occurring in the yacht shell lamination process, and thus shorten the time needed to repair errors and the total time of producing the yacht.

  • The Timber economy in the Baltic Sea, 1600-1939
    • Luciano Segreto
    2024

    The work analyses the evolution of the timber economy in the Baltic Sea from the 17th century until WW2

  • The (Un)Real City by Magdalena Abakanowicz: Guidelines for Cities in Times of Planetary Crisis
    • Izabela Mironowicz
    2024 Pełny tekst TEKA KOMISJI URBANISTYKI I ARCHITEKTURY Oddział PAN w Krakowie

    Three decades have passed since Magdalena Abakanowicz presented her concept of Bois de Nanterre — Arboreal Architecture, in response to a call for a broader reflection on approaches to urban landscaping and a reinterpretation of the meaning and evolution of the Grand Axis in Paris. This paper analyses the work presented by the artist from an urban planning perspective. It shows how the rich and multi-layered metaphor for the 21st-century city, embodied in the concept of the Bois de Nanterre, offers a pioneering and radical lesson for addressing contemporary urban problems.

  • The use of a 4 PB strain sweep fatigue test to evaluate characteristics of carbon grid reinforced asphalt beams
    • Marcin Stienss
    • Piotr Jaskuła
    • Cezary Szydłowski
    2024

    The article presents research results concerning pre-bituminized carbon grids for asphalt pavement reinforcement, which are used to prevent cracking and crack reflection thus increasing bearing capacity and durability of pavement. Research program involved testing of large sized double-layer samples, both reinforced and unreinforced. The advantage of using a carbon grid was especially visible after crack initiation. The energy during crack propagation phase was about three times higher in comparison with unreinforced samples. The maximum dissipated energy was significantly higher in the fatigue test for a reinforced samples, with also higher level of tensile strain.

  • The use of a genetic algorithm in the process of optimizing the shape of a three-dimensional periodic beam
    • Łukasz Doliński
    • Arkadiusz Żak
    • Wiktor Waszkowiak
    • Paweł Kowalski
    • Jacek Szkopek
    2024 Journal of Theoretical and Applied Mechanics

    Mechanical periodic structures exhibit unusual dynamic behavior thanks to the periodicity of their structures, which can be attributed to their cellular arrangement. The source of this periodicity may result from periodic variations of material properties within their cells and/or variations in the cell geometry. The authors present the results of their studies on the optimization of physical parameters of a three-dimensional axisymetrical periodic beam in order to obtain the desired vibroacoustic properties. The aim of the optimization process of the unit cell shape was to obtain band gaps of a given width and position in the frequency spectrum.

  • The use of accumulation elements with lumped parameters to model the operation of heat exchange installations under randomly changing temperatures
    • Jacek Kropiwnicki
    • Bartosz Dawidowicz
    • Przemysław Wojewódka
    • Andrzej Rogala
    2024 Chemical and Process Engineering : New Frontiers

    At the design stage of heat exchange installation used for gas conversion it is required to test the stability of the installation operation for the expected variable heat loads. For this purpose, a numerical model of the installation can be used. The paper presents an original concept of modelling the operation of heat exchange installations for randomly changing temperatures. Accumulation elements with lumped parameters were used in the model, which significantly facilitates the definition of model parameters and the calculation itself at the design stage. Due to the randomly changing temperatures supplying the accumulation element by the heating medium and the non-linear nature of the functions used in the calculation model, the iterative procedure was used for calculations. The process of validation of the proposed computational model of the accumulation element with lumped parameters was carried out for a water installation powered by a natural gas-fired boiler. The obtained results showed very good accuracy of the applied approach, the root mean square error for tested data has reached 1 ◦C to 3 ◦C, depending on the analysed case.

  • The use of chain extenders as processing aids in the valorization of single-use polylactide (PLA) products by rotomolding
    • Mateusz Barczewski
    • Joanna Aniśko
    • Aleksander Hejna
    • Mariusz Marć
    • Marta Safandowska
    • Krzysztof Lewandowski
    • Zaida Ortega
    • Patryk Mietliński
    • Jacek Andrzejewski
    2024 JOURNAL OF CLEANER PRODUCTION

    Biodegradable plastics in single-use products have increased in popularity as a way to reduce the negative environmental impact of conventional plastics and meet the tightening law regulations. However, their recyclability needs to be assessed, as the environmental behavior of single-use plastics, even if compostable, is not negligible. Polylactide (PLA) is susceptible to thermal, oxidative, hydrolytic, and mechanical degradation during reprocessing, so the conditions of such cycles must be accurately controlled. The necessity of using additives to reduce such degradations during rotational molding, a process with long cycle times and oxidizing atmosphere, has been demonstrated. Chain extenders based on a carbodiimide (Bioadimide® 100 - KI), a methylene diphenyl diisocyanate (MDI), and a polystyrene-acrylic copolymer (Joncryl® ADR-4368c - J) have been added to postconsumer PLA wastes. It has been demonstrated that these three chain extenders enabled obtaining a higher molecular weight of the reprocessed polymer, compared to the ~50% reduction for the neat PLA. The use of carbodiimide yielded the most similar performance to that of unprocessed raw material. All samples provided adequate thermal stability and processing parameters for the rotational molding. Carbodiimide is considered the most efficient additive, as it increases the molecular mass of the polymer as it remains unchanged after processing. Similarly, KI-modified PLA rheological behavior remains unchanged after processing, which means this compound can reduce thermooxidative and hydrolytic degradation reactions. Thus contributing to the achievement of improved processability and better performance; in particular, impact strength increased from 1.06 ± 0.56 for PLA to 8.12 ± 2.28 kJ/m2 for KI-modified PLA, and toughness of 5.36 ± 1.61 to 61.49 ± 8.01 J/ mm3, respectively, leading to rotomolded items without structural defects. On the opposite, the use of Joncryl® and MDI led to structural defects in the rotomolded parts despite a higher molecular weight of the polymer, which resulted in poor mechanical properties, although better than PLA without any additive. All three chain extenders resulted in an amorphous PLA structure with increased glass transition temperature and improved thermal stability, which correlated with the reduced emissions of volatile compounds compared to neat recycled PLA.

  • The Use of Cluster Analysis to Assess the Wear Resistance of Cermet Coatings Sprayed by High Velocity Oxy-Fuel on Magnesium Alloy Substrate
    • Ewa Stanisława Jonda
    • Dariusz Fydrych
    • Leszek Łatka
    • Hanna Myalska-Głowacka
    2024 Advances in Science and Technology Research Journal

    Cermet coatings are one of the best surface protection of machine elements against wear. On the other hand, the most universal and economically justified method of applying such coatings is high velocity oxy-fuel (HVOF) spraying. This method makes it possible to produce coatings characterized by compact structure, low porosity and very good adhesion to the substrate. All these fundamental properties contribute to the high wear resistance of these coatings. However, carrying out full wear tests (e.g. ball-on-disc) is time-consuming, especially when it is necessary to select the proper feedstock material and carefully selected process parameters. The aim of the following researches was to statistically investigate the possibility of replacing long-term wear resistance tests with estimation of this performance on the basis of determining the fundamental mechanical properties of the coatings. Three types of coating materials were selected: WC-12Co, WC-10Co-4Cr and WC-20Cr3 C2 -7Ni, which were deposited on AZ31 magnesium alloy substrates from three different spray distances: 320, 360 and 400 mm. On the basis of the tests carried out and using cluster analysis techniques (the Ward and k-means methods), the relative similarity between the obtained coatings was determined. The applied methodology allowed to select from the analyzed cermet coatings such samples that were characterized by improved resistance to abrasive wear. The obtained results of the analyzes were also referred to the results of tests of resistance to abrasive wear

  • The Use of Ultra-Fast Gas Chromatography for Fingerprinting-Based Classification of Zweigelt and Rondo Wines with Regard to Grape Variety and Type of Malolactic Fermentation Combined with Greenness and Practicality Assessment
    • Anna Stój
    • Wojciech Wojnowski
    • Justyna Płotka-Wasylka
    • Tomasz Czernecki
    • Ireneusz Kapusta
    2024 MOLECULES

    In food authentication, it is important to compare different analytical procedures and select the best method. The aim of this study was to determine the fingerprints of Zweigelt and Rondo wines through headspace analysis using ultra-fast gas chromatography (ultra-fast GC) and to compare the effectiveness of this approach at classifying wines based on grape variety and type of malolactic fermentation (MLF) as well as its greenness and practicality with three other chromatographic methods such as headspace solid-phase microextraction/gas chromatography-mass spectrometry with carboxen-polydimethylosiloxane fiber (SPME/GC-MS with CAR/PDMS fiber), headspace solid-phase microextraction/gas chromatography-mass spectrometry with polyacrylate fiber (SPME/GC-MS with PA fiber), and ultra performance liquid chromatography–photodiode array detector-tandem mass spectrometry (UPLC-PDA-MS/MS). Principal Component Analysis (PCA) revealed that fingerprints obtained using all four chromatographic methods were suitable for classification using machine learning (ML). Random Forest (RF) and Support Vector Machines (SVM) yielded accuracies of at least 99% in the varietal classification of Zweigelt and Rondo wines and therefore proved suitable for robust fingerprinting-based Quality Assurance/Quality Control (QA/QC) procedures. In the case of wine classification by the type of MLF, the classifiers performed slightly worse, with the poorest accuracy of 91% for SVM and SPME/GC-MS with CAR/PDMS fiber, and no less than 93% for the other methods. Ultra-fast GC is the greenest and UPLC-PDA-MS/MS is the most practical of the four chromatographic methods.

  • The Yin and Yang of hsa-miR-1244 expression levels during activation of the UPR control cell fate
    • Paulina Czechowicz
    • Magdalena Gebert
    • Sylwia Bartoszewska
    • Leszek Kalinowski
    • James F. Collawn
    • Rafał Bartoszewski
    2024 Pełny tekst Cell Communication and Signaling

    Regulation of endoplasmic reticulum (ER) homeostasis plays a critical role in maintaining cell survival. When ER stress occurs, a network of three pathways called the unfolded protein response (UPR) is activated to reestablish homeostasis. While it is known that there is cross-talk between these pathways, how this complex network is regulated is not entirely clear. Using human cancer and non-cancer cell lines, two different genome-wide approaches, and two different ER stress models, we searched for miRNAs that were decreased during the UPR and surprisingly found only one, miR-1244, that was found under all these conditions. We also verified that ER-stress related downregulation of miR-1244 expression occurred with 5 different ER stressors and was confirmed in another human cell line (HeLa S3). These analyses demonstrated that the outcome of this reduction during ER stress supported both IRE1 signaling and elevated BIP expression. Further analysis using inhibitors specific for IRE1, ATF6, and PERK also revealed that this miRNA is impacted by all three pathways of the UPR. This is the first example of a complex mechanism by which this miRNA serves as a regulatory check point for all 3 pathways that is switched off during UPR activation. In summary, the results indicate that ER stress reduction of miR-1244 expression contributes to the pro-survival arm of UPR.

  • Theoretical modelling of efficient fire safety water networks by certified domination
    • Joanna Raczek
    • Mateusz Miotk
    2024 Pełny tekst Scientific Reports

    This paper explores a new way of designing water supply networks for fire safety using ideas from graph theory, focusing on a method called certified domination. Ensuring a good water supply is crucial for fire safety in communities, this study looks at the rules and problems in Poland for how much water is needed to fight fires in different areas and how this can be achieved at a lowest possible cost. We present a way to plan water supply networks for fire protection as a graph, where each point(node) is a place that needs water, and the lines (links) show where water can go between these points.The main idea is to find the best places to put pumping stations and wells in the network to save money and still meet all the fire safety requirements. Our approach assumes that it costs more to build a pumping station than a well. We use some examples to show how this method can find cost-effectivesolutions for water supply networks, while ensuring that they meet fire safety requirements and are not too expensive to build. This approach is a new and efficient way to improve the design of water supply networks for fire safety. Key challenges that are solved in this paper are a linear time algorithm finding an optimal solution for networks without cycles and a BLP (Binary Linear Programming)algorithm solving the problem in arbitrary networks.