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  • 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 brace to chord rotational connection stiffness on stability of the truss
    • Marcin Krajewski
    2024 Bulletin of the Polish Academy of Sciences-Technical Sciences

    The paper is devoted to the numerical analysis of the roof truss subjected to upward wind loading and braced at the tensioned top chord. The linear buckling analysis were performed for the beam and shell model of the structure. As the result the influence of rotational connection stiffness between the brace and the top chord on the truss stability was appointed. The biaxial strength testing machine was used to conduct the experimental tests of the rotational connection stiffness between selected steel profiles. The results in the form of measured structural displacements and rotations were presented. The static nonlinear analysis results performed for the shell model of the structural connection were compared to the results obtained on the experimental set-up.

  • 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 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 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

    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 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 (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.