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Torque capacity of multidisc wet clutch with reference to friction occurrence on its spline connections
PublicationIn this article developed mathematical model that includes friction occurrence on spline connections is presented. The work also contains results of experimental research on torque capacity of multidisc wet clutch. These results are expressed as a function of contact pressure for different number of friction surfaces. Due to increased interest in research concerning multidisc wet clutches it is essential to determine impact of...
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Influence of addition of carbon nanotubes on rheological properties of selected liquid lubricants - a computer simulation study
PublicationThis work is motivated by the improvement of anti-friction properties of lubricants by addition of CNTs proved experimentally in literature. In particular, a methodology is developed to compute the shear viscosity of liquid lubricants (Propylene Glycol) based on Molecular Dynamics simulation. Non-Equilibrium molecular dynamics (NEMD) approach is used with a reactive force field ReaxFF implemented in LAMMPS. The simulations are...
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Design of a Patch Power Divider with Simple Structure and Ultra-Broadband Harmonics Suppression
PublicationThis paper introduces a simple H-shaped patch Wilkinson power divider (WPD), which provides ultra wide harmonics suppression band. The presented WPD designed at 1.8 GHz, and exhibits good performance at the operating bandwidth. In the proposed divider structure, two simple patch low-pass filters (LPFs) are employed at each branch, and three open ended stubs are added at each port. The proposed divider, implemented using the aforementioned...
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Heat exchange enhancement of jet impingement cooling with the novel humped-cone heat sink
PublicationJet impingement cooling technology is applicable to control temperature of devices, where very high heat flux is generated within a small area. This paper is about the improvement of the jet impingement cooling efficiency by the heat sink geometry modification. Two reference cases were sourced from the literature – flat heat sink and modified one with cone in the jet stagnation region. Such a change improves cooling capability...
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Family Tree for Aqueous Organic Redox Couples for Redox Flow Battery Electrolytes: A Conceptual Review
PublicationRedox flow batteries (RFBs) are an increasingly attractive option for renewable energy storage, thus providing flexibility for the supply of electrical energy. In recent years, research in this type of battery storage has been shifted from metal-ion based electrolytes to soluble organic redox-active compounds. Aqueous-based organic electrolytes are considered as more promising electrolytes to achieve “green”, safe, and low-cost...
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Arithmetic Loophole in Bell's Theorem: Overlooked Threat to Entangled-State Quantum Cryptography
PublicationBell’s theorem is supposed to exclude all local hidden-variable models of quantum correlations. However,an explicit counterexample shows that a new class of local realistic models, based on generalized arith-metic and calculus, can exactly reconstruct rotationally symmetric quantum probabilities typical oftwo-electron singlet states. Observable probabilities are consistent with the usual arithmetic employedby macroscopic observers...
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University Students’ Research on Artificial Intelligence and Knowledge Management. A Review and Report of Multi-case Studies
PublicationLeading technologies are very attractive for students preparing their theses as the completion of their studies. Such an orientation of students connected with professional experiences seems to be a crucial motivator in the research in the management and business areas where these technologies condition the development of professional activities. The goal of the paper is the analysis of students’ thesis topics defended in the last...
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Clays as Inhibitors of Polyurethane Foams’ Flammability
PublicationPolyurethanes are a very important group of polymers with an extensive range of applications in different branches of industry. In the form of foams, they are mainly used in bedding, furniture, building, construction, and automotive sectors. Due to human safety reasons, these applications require an appropriate level of flame retardance, often required by various law regulations. Nevertheless, without the proper modifications,...
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On coertia and inertia in aspects of Natanson’s nonlinear extended thermodynamics
PublicationIn this article, the previously underrepresented contributions of Natanson to the field of thermodynamics have been presented. In order to identify a source of irreversibility at Nature, Natanson introduced the concept of Coertia, which is similar to inertia. Natanson’s Coertia is a fundamental property of space that is responsible for every irreversible phenomena in matter, as well as in the electromagnetic and gravitational fields....
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Numerically Efficient Miniaturization-Oriented Optimization of an Ultra-Wideband Spline-Parameterized Antenna
PublicationDesign of ultra-wideband radiators for modern handheld applications is a challenging task that involves not only selection of an appropriate topology, but also its tuning oriented towards balancing the electrical performance and size. In this work, a low-cost design of a compact, broadband, spline-parameterized monopole antenna has been considered. The framework used for the structure design implements trust-region-based methods,...
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Digital transformation and economic growth - DESI improvement and implementation
PublicationThe paper aims to improve the methodology of the Digital Economic and Society Index (DESI), the European Commission’s newest index to assess the development of the digital economy. In particular, we investigate whether methodological changes to the structure of DESI improve its ability to capture the digital transformation of EU economies. Using the sensitivity- based analysis, we check whether the selection of weights of individual...
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Current Trends in Wick Structure Construction in Loop Heat Pipes Applications: A Review
PublicationThermal control systems have been introduced as an important part of electronic devices, enabling thermal management of their electronic components. Loop heat pipe (LHP) is a passive two-phase heat transfer device with significant potential for numerous applications, such as aerospace applications, high-power LEDs, and solar central receivers. Its advantages are high heat transfer capability, low thermal resistance, long-distance...
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A Tutorial on AGREEprep an Analytical Greenness Metric for Sample Preparation
PublicationSample preparation is a key step in the analytical procedure and a critical component for achieving analytical greenness. AGREEprep is the first metric intended for evaluating the environmental impact of sample preparation methods. The approach consists of ten steps of assessment that correspond to the ten principles of green sample preparation and uses a user-friendly open-source software to calculate and visualize the results....
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A Surrogate-Assisted Measurement Correction Method for Accurate and Low-Cost Monitoring of Particulate Matter Pollutants
PublicationAir pollution involves multiple health and economic challenges. Its accurate and low-cost monitoring is important for developing services dedicated to reduce the exposure of living beings to the pollution. Particulate matter (PM) measurement sensors belong to the key components that support operation of these systems. In this work, a modular, mobile Internet of Things sensor for PM measurements has been proposed. Due to a limited...
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Cycling as a Sustainable Transport Alternative in Polish Cittaslow Towns
PublicationIt is well known that growing motor traffic in urban areas causes air pollution and noise which affects the environment and public health. It is hardly surprising then that cycling should be used as an alternative mode of transport, not just in major cities but also in smaller ones including those that are members of the Cittaslow network. Their approach is based on sustainable development, care for the environment and transport...
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Nonlinear dynamic analysis of the pure “buckling” mechanism during blow-out trauma of the human orbit
PublicationConsidering the interplay between orbital bones and intraorbital soft tissues, commonly accepted patterns of the blow-out type of trauma within the human orbit require more thorough investigation to assess the minimal health-threatening impact value. Two different three-dimensional finite element method (FEM) models of the human orbital region were developed to simulate the pure “buckling” mechanism of orbital wall fracture in...
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Open Data Capability Architecture - An Interpretive Structural Modeling Approach
PublicationDespite of increasing availability of open data as a vital organizational resource, large numbers of startups and organizations fail when it comes to utilizing open data effectively. This shortcoming is attributable to the poor understanding of what types of capabilities are required to successfully conduct data related activities. At the same time, research on open data capabilities and how they relate to one another remains sparse....
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Revisiting the estimation of cutting power with different energetic methods while sawing soft and hard woods on the circular sawing machine: a Central European case
PublicationIn the classical approaches, used in Central Europe in practice, cutting forces and cutting power in sawing processes of timber are commonly computed by means of the specific cutting resistance kc. It needs to be highlighted that accessible sources in handbooks and the scientific literature do not provide any data about wood provenance, nor about cutting conditions, in which cutting resistance has been empirically determined. In...
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Thermohydraulic maldistribution reduction in mini heat exchangers
PublicationA detailed numerical investigation has been carried out to analyze the flow maldistribution in 50 parallel 1 mm × 1 mm rectangular minichannels and 1 mm depth minigap section with rectangular, trapezoidal, triangular or concave manifolds in Z-type flow configuration. The working medium was ethanol and the mass flow rate was 5 × 10−4 kg/s. Both sections were heated from the bottom side. Heat flux of 10 000 W/m2 and 5000 W/m2 was...
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Design-oriented computationally-efficient feature-based surrogate modelling of multi-band antennas with nested kriging
PublicationDesign of modern antenna structures heavily depends on electromagnetic (EM) simulation tools. EM analysis provides reliable evaluation of increasingly complex designs but tends to be CPU intensive. When multiple simulations are needed (e.g., for parameters tuning), the aggregated simulation cost may become a serious bottleneck. As one possible way of mitigating the issue, the recent literature fosters utilization of faster representations,...
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Absolute Photoabsorption Cross-Sections of Methanol for Terrestrial and Astrophysical Relevance
PublicationWe investigate the methanol absorption spectrum in the range 5.5–10.8 eV to provide accurate and absolute cross-sections values. The main goal of this study is to provide a comprehensive analysis of methanol electronic-state spectroscopy by employing high-resolution vacuum ultraviolet (VUV) photoabsorption measurements together with state-of-the-art quantum chemical calculation methods. The VUV spectrum reveals several new features...
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Potential applications of by-products from the coffee industry in polymer technology – Current state and perspectives
PublicationCoffee is one of the most popular beverages in the world, and its popularity is continuously growing, which can be expressed by almost doubling production over the last three decades. Cultivation, processing, roasting, and brewing coffee are known for many years. These processes generate significant amounts of by-products since coffee bean stands for around 50% of the coffee cherry. Therefore, considering the current pro-ecological...
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Chemical, Physical, and Mechanical Properties of 95-Year-Old Concrete Built-In Arch Bridge
PublicationThis research aimed to determine the durability and strength of an old concrete built-in arch bridge based on selected mechanical, physical, and chemical properties of the concrete. The bridge was erected in 1925 and is located in Jagodnik (northern Poland). Cylindrical specimens were taken from the side ribs connected to the top plate using a concrete core borehole diamond drill machine. The properties of the old concrete were...
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Dynamic modeling of non-cylindrical curved viscoelastic single-walled carbon nanotubes based on the second gradient theory
PublicationThis paper is devoted to the theoretical study of the dynamic response of non-cylindrical curved viscoelastic single-walled carbon nanotubes (SWCNTs). The curved nanotubes are largely used in many engineering applications, but it is challenging in understanding mechanically the dynamic response of these curved SWCNTs when considering the influences of the material viscosity. The viscoelastic damping effect on the dynamic response...
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Zróżnicowanie zadłużenia w zależności od wielkości przedsiębiorstwa
PublicationW artykule przedstawiono różnice w sposobie kształtowania wartości wskaźników z obszaru zadłużenia pomiędzy małymi, średnimi i dużymi przedsiębiorstwami. W trakcie przeprowadzonych badań uwzględniono 97 471 sprawozdań finansowych przedsiębiorstw, prowadzących działalność gospodarczą w 12 różnych działach polskiej gospodarki narodowej. Do potwierdzenia zróżnicowania zadłużenia w zależności od wielkości przedsiębiorstwa wykorzystano...
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Wino – uzupełnienie czy dominujący składnik portfela inwestycyjnego o minimalnym ryzyku
PublicationCel – Określenie struktury portfela inwestycyjnego o minimalnym ryzyku, składającego się z inwestycji na rynku win oraz z inwestycji w akcje spółek notowanych na wybranych giełdach Europy Środkowo-Wschodniej. Metodologia badania – Konstrukcja portfeli inwestycyjnych zgodnie z teorią zaproponowaną przez H.M. Markowitza, poparta badaniami literaturowymi odnoszącymi się do zagadnienia ekonomii wi-na. Wynik – Inwestycja w wino może...
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ZMIANY STRUKTURY DEMOGRAFICZNEJ LUDNOŚCI – WYZWANIA DLA RYNKU PRACY
PublicationPolska, podobnie jak i inne kraje europejskie doświadcza w przyspieszonym tempie zmian demograficznych, które w krajach o rozwiniętych gospodarkach rynkowych rozpoczęły się w latach 60. XX wieku. Procesy nieodwracalne, związane ze starzeniem się społeczeństwa na początku zaobserwowano w Skandynawii, następnie proces ten objął kraje Europy Zachodniej, Europy Południowej, w latach 90. XX wieku – również Europę Środkową i Wschodnią....
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Udział pracy w dochodzie narodowym w Polsce z uwzględnieniem województw
PublicationW literaturze przedmiotu wskazuje się na liczne przyczyny występowania zmian udziału pracy w dochodzie narodowym. Zróżnicowanie udziału pracy w dochodzie narodowym można badać nie tylko w skali światowej, ale również odnosząc się do poszczególnych gospodarek i regionów. Celem niniejszego artykułu jest zbadanie zróżnicowania udziału czynnika pracy w dochodzie narodowym w poszczególnych województwach w Polsce. Zakres opracowania...
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ZARZĄDZANIE ZESPOŁEM WIRTUALNYM JAKO WYZWANIE DLA LIDERA ZESPOŁU
PublicationRozdział dotyczy zarządzania zespołem wirtualnym, który charakteryzuje się rozproszeniem członków zespołu oraz współpracą za pośrednictwem technologii informacyjnej. Tak funkcjonujące zespoły nakładają na lidera dodatkowe wyzwania związane z koniecznością kompensowania braku bezpośredniego kontaktu oraz samodzielnością poszczególnych osób w zespole. Przedstawiono najważniejsze zadania, które podnoszą efektywność zarządzania zespołem...
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ZRÓŻNICOWANIE PŁYNNOŚCI FINANSOWEJ W ZALEŻNOŚCI OD WIELKOŚCI PRZEDSIĘBIORSTWA
PublicationW artykule przedstawiono różnice w sposobie kształtowania wartości wskaźników z obszaru płynności finansowej pomiędzy małymi, średnimi i dużymi przedsiębiorstwami. W trakcie przeprowadzonych badań uwzględniono 97 471 sprawozdań finansowych przedsiębiorstw, prowadzących działalność gospodarczą w 12 różnych działach polskiej gospodarki narodowej. Do potwierdzenia zróżnicowania płynności finansowej w zależności od wielkości przedsiębiorstwa...
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Blogi jako platforma komunikowania na przykładzie blogów uczelnianych
PublicationW artykule stawiam tezę o istotnej roli blogów jako niezwykle skutecznej platformie komunikacyjnej w dobie konwergencji mediów. Szczególnie ważną rolę to specyficzne narzędzie komunikacyjne może odegrać w działaniach public relations uczelni: jako narzędzie za pomocą którego można najpełniej realizować funkcje uczelni i te, które realizuje najwyższy poziom rozwoju PR - w komunikacji dwukierunkowej symetrycznej zgodnie z modelem...
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UWARUNKOWANIA I SKUTKI ŻYWIOŁOWEJ SUBURBANIZACJI W POLSCE. CZY OPANOWANIE JEJ JEST MOŻLIWE?
PublicationArtykuł dotyczy procesu żywiołowej suburbanizcji (urban sprawl) w Polsce. Jego celami są: (1) analiza powiązań między negatywnymi skutkami tego procesu, (2) prezentacja negatywnych skutków dla transportu i zużycia energii oraz ładu przestrzennego, (3) analiza sposobów przeciwdziałania negatywnym procesom, w tym uwarunkowań (w szczególności ograniczeń) stosowania tych sposobów i ich skuteczności. Jako metody zastosowano: obserwację,...
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Sektorowe zróżnicowanie płynności finansowej przed-siębiorstw
PublicationPłynność finansowa warunkuje prawidłowość funkcjonowania całej firmy. Uzależniona jest od niej możliwość przetrwania przedsiębiorstwa na rynku oraz perspektywa jego rozwoju. Artykuł podejmuje tematykę zróżnicowania płynności finansowej przedsiębiorstw w zależności od ich przynależności sek-torowej. Z przeprowadzonych badań wynika, że wartość wskaźników z obsza-ru płynności finansowej jest silnie zróżnicowana w przekroju sektorowym....
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Moda jako wartość konsumencka - eksplikacja zagadnienia
PublicationCel: Celem artykułu jest przedstawienie problematyki mody jako propozycji wartości dla klienta. Realizacja niniejszego celu wymagała uszczegółowionej eksplikacji zjawiska mody. W publikacji zdefiniowaniu poddano mechanizm działania mody, istotę trendu mody, jak również omówiono główne perspektywy analizy mody oraz aktualne nurty badań nad modą. Projekt badania/metodyka badawcza/koncepcja: W pracy wykorzystano metodę krytycznej...
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Inflation Forecast or Forecast(s) Targeting?
PublicationThe paper refers to L.E.O. Svensson’s concept of inflation forecast targeting (IFT) and its implementation by central banks of Sweden, Norway and the Czech Republic. The study focuses on (1) inflation forecasts published by selected central banks, i.e.headline inflation and core or monetary policy-relevant (MPR) inflation, which are made on the assumption of endogenous instrument rate, (2) one-year consumer...
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Machine Learning Techniques in Concrete Mix Design
PublicationConcrete mix design is a complex and multistage process in which we try to find the best composition of ingredients to create good performing concrete. In contemporary literature, as well as in state-of-the-art corporate practice, there are some methods of concrete mix design, from which the most popular are methods derived from The Three Equation Method. One of the most important features of concrete is compressive strength, which...
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Online Interactivity – Shift Towards E-textbook-based Medical Education
PublicationTextbooks have played the leading role in academic education for centuries and their form has evolved, adapting to the needs of students, teachers and technological possibilities. Advances in technology have caused educators to look for new sources of knowledge development, which students could use inside and outside the classroom. Today’s sophisticated learning tools range from virtual environments to interactive multimedia resources,...
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Modelling the time-dependent behaviour of soft soils
PublicationTime-dependence of soft soils has already been thoroughly investigated. The knowledge on creep and relaxation phenomena is generally available in the literature. However, it is still rarely applied in practice. Regarding the organic soils, geotechnical engineers mostly base their calculations on the simple assumptions. Yet, as presented within this paper, the rate-dependent behaviour of soft soils is a very special and important...
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Adaptabilność obiektów architektonicznych we współczesnym projektowaniu / The adaptability of architectural objects in contemporary design
PublicationThe article discusses the issue of adaptability - the ability to modify modern architectural objects to a changing context - as an important element of contemporary design. Adaptability can take on different forms. It is most commonly understood as a change in the architectural form in reaction to various stimuli from the environment through transformative structures, or as an object's ability to adapt to climatic conditions, providing...
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Raman investigation of the patina layers on Hungarian copper ingots from a fifteenth century shipwreck
PublicationWe report results of the patina study of underwater archeological finding ofmedieval copper objects performed by means of the Raman and complementary spectroscopic techniques. The objects were found submerged in the sea as cargo part of the ship which sunk in the Gulf of Gdańsk in 1408. The excavated collection consists of 230 oval ingots of the size and mass up to about 60 cm and 18 kg (total of 2 tons), respectively. In the Raman...
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Solubility Characteristics of Acetaminophen and Phenacetin in Binary Mixtures of Aqueous Organic Solvents: Experimental and Deep Machine Learning Screening of Green Dissolution Media
PublicationThe solubility of active pharmaceutical ingredients is a mandatory physicochemical characteristic in pharmaceutical practice. However, the number of potential solvents and their mixtures prevents direct measurements of all possible combinations for finding environmentally friendly, operational and cost-effective solubilizers. That is why support from theoretical screening seems to be valuable. Here, a collection of acetaminophen...
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ASSESSMENT OF TOXIC EFFECT AND ENDOCRINE POTENTIAL OF FOOD PACKAGES EXTRACTS
PublicationIn the scientific literature related to the widely understood issue of packaging materials designed to have contact with food there is much information on raw materials used for their production, their physiochemical properties, types and parameters. There is also a great number of publications on the management and disposal of used packaging. Unfortunately, not much attention is given to the matters concerning migration of toxic...
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Ongoing progress on novel nanocomposite membranes for the separation of heavy metals from contaminated water
PublicationMembranes, as the primary separation element of membrane-based processes, have greatly attracted the attention of researchers in several water treatment applications, including wastewater treatment, water purification, water disinfection, toxic and non-toxic chemical molecules, heavy metals, among others. Today, the removal of heavy metals from water has become challenging, in which chemical engineers are approaching new materials...
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An Overview of Sport and the Future Smart Cities
PublicationOne of the main challenges for future cities is to strengthen the role of people and their activities. Therefore, sport provides an opportunity to engage in physical activity, connecting citizens to the city. The question of how sport influences the development of cities and the concept of future smart cities arises. The aim of this study is to examine the relationship between sport and the concept of smart cities by identifying...
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Exploring avian exposure to parent polycyclic aromatic hydrocarbons (PAHs): Using the common eider Somateria mollissima in a global context
PublicationCompared to other organic contaminants, birds are rarely studied for their exposure to polycyclic aromatic hydrocarbons (PAHs), mainly due to their effective metabolization of parent PAHs. However, as some studies suggest, exposure to PAHs may result in adverse health effects including decreased survival, especially following oil spills. In the present study, we analyzed samples from a sea duck, the common eider Somateria mollissima...
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Toward an understanding of occupational burnout among employees with autism – the Job Demands‑Resources theory perspective
PublicationThis article aims to gain insight into the phenomenon of occupational burnout among employees with autism based on the theoretical framework of the Job Demands-Resources theory and the literature on employees with autism in the workplace. Firstly, we argue that although the resources and demands of the neurotypical and neurodivergent employees might be different, the theoretical mechanism of occupational burnout formation remains...
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Exergetic Analysis of the nCO2PP Cycle with Particular Reference to the Exergy Destruction of Sewage Sludge Due to Gasification
PublicationAn exergy analysis is carried out on the negative CO2 emission gas power plant (nCO2PP), which integrates the process sections of fuel preparation, power generation and carbon capture. Processes of exergy destruction are studied with particular focus on the process in the gasification unit of the fuel preparation section, where a large amount of exergy is destroyed in various chemical reactions from sewage sludge to producer gas...
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Planning Around Polarisation: Components of Finding Common Ground Based on Regeneration Projects in London and Gdańsk
PublicationVarious forms of public participation in urban design and planning—as presented and discussed in literature—have recently been challenged by the needs and expectations of different stakeholders, including those coming from the private sector. This comes with a redefinition of the public good and the roles and responsibilities of municipal authorities in post‐liberal times. As a result, contemporary participatory processes need...
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Trends in Locally Balanced Energy Systems without the Use of Fossil Fuels: A Review
PublicationIn recent years, the idea of the operation of energy systems (power systems, heating systems) has changed significantly. This paper is an overview of locally balanced energy systems without the use of fossil fuels. The paper justifies the concept of local energy balancing in a new energy system that does not use fossil fuels (coal, natural gas, and crude oil), based on European Union guidelines and formal documents as well as the...
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Antecedents and outcomes of social media fatigue
PublicationPurpose – This study aims to explore which of four chosen factors (i.e. privacy concerns, FoMO, self-disclosure and time cost) induce a feeling of strain among Facebook users in terms of social media fatigue (SMF), and if this occurs, whether it further influences such outcomes as discontinuance of usage (DoU) and interaction engagement decrement (IED). Design/methodology/approach – Through an online structured questionnaire, empirical...