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Rok 2025
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3D DEM modelling of acoustic emission in concrete: Insights into elastic waves initiated by microcracks
PublikacjaIn this paper, 3-point bending concrete beams were investigated through a combination of experimental and numerical analyses. Initially, laboratory tests were conducted to observe the formation and propagation of cracks using acoustic emission (AE) and digital image correlation (DIC) techniques. The experimental results obtained were then compared with a numerical study. The widely used discrete element method (DEM), implemented...
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A Compact Tri-Band Omnidirectional Antenna Design for CubeSat Applications
PublikacjaThis paper presents a compact tri-band omnidirectional antenna designed for CubeSat applications, operating at UHF (0.755 GHz), L-band (1.25 GHz), and S-band (2.28–3.74 GHz). The antenna features a defected ground structure (DGS) and metallic vias, which enhance impedance matching and enable stable multi-band resonance while maintaining a small footprint of 0.26λ × 0.26λ × 0.013λ within a 1U CubeSat. Unlike conventional CubeSat...
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A Miniaturized and High Optically Transparent Frequency Selective Surface for RF Shielding using Double-Glazed Glass Windows for Green Building Applications
PublikacjaThis research presents a miniaturized and high optically transparent (OT) frequency selective surface (FSS) for achieving RF shielding through glass window panels. The proposed FSS consists of a single-layered copper pattern sandwiched between two ordinary glass substrates to suppress the dual bands of sub-6 fifth generation (5G). In particular, the design effectively shields n65-downlink (2.1 GHz) and a portion of n78-band (3.5...
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A Non-PCM-Based 2 × 2 MIMO Antenna Array With Low Radar Cross-Section Using Characteristic Mode Analysis
PublikacjaIn this paper, we introduced a 2×2 multiple-input-multiple-output (MIMO) antenna array using a non-polarization conversion metasurface (NPCM) with reduced radar cross section (RCS). To achieve a low RCS, a chess-board configuration is typically adopted. However, in conventional NPCM designs, subarrays with 180◦ phase shifts apart exhibit radiating modes at different resonance frequencies due to varied unit cell sizes and spacing....
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A procedure for simulation-assisted identification of ultrasonic wave attenuation in heterogeneous materials and its application to the detection of fracture in concrete beams
PublikacjaIn this study, a novel procedure for identification of ultrasonic wave attenuation in heterogeneous materials based on signal energy was presented. The main objective was to develop a method for simple and robust determination of wave characteristics for further use in numerical modelling of ultrasonic wave propagation including attenuation of signals. Experimental investigations supported by numerical simulations were proposed...
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A Review: Structural Shape and Stress Control Techniques and their Applications
PublikacjaThis review article presents prior studies on controlling shape and stress in flexible structures. The study offers a comprehensive survey of literature concerning the adjustment and regulation of shape, stress, or both in structures and emphasizes such control’s importance. The control of systems is classified into three primary classes: nodal movement control, axial force control, and controlling the two classes concurrently....
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Activation of small molecules by ambiphilic NHC-stabilized phosphinoborenium cation: formation of boreniums with B–O–C, B–O–B, and B–O–P structural motifs
PublikacjaThe reactivity of the phosphinoborenium cation supported by a 1,3,4,5-tetramethylimidazolin-2-ylidene ligand toward small molecules was explored. The phosphinoborenium cation exhibited dual Lewis acid–base properties due to the presence of the Lewis acidic boron center and the Lewis basic phosphido ligand connected by a covalent bond. The reaction of the title cation with CO2 led to the insertion of a CO2 molecule into the P–B...
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Active learning on stacked machine learning techniques for predicting compressive strength of alkali-activated ultra-high-performance concrete
PublikacjaConventional ultra-high performance concrete (UHPC) has excellent development potential. However, a significant quantity of CO2 is produced throughout the cement-making process, which is in contrary to the current worldwide trend of lowering emissions and conserving energy, thus restricting the further advancement of UHPC. Considering climate change and sustainability concerns, cementless, eco-friendly, alkali-activated UHPC (AA-UHPC)...
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Agile Mindset, Technological vs. Non-technological Mindset, and Gender. Are They Related?
PublikacjaThis study examined the impact of gender on the relationship between employees' agile and non-agile mindsets and organisational agility. It also considers the tech and non-tech focus as a potential moderator. The initial sample of 209 knowledge workers andthe replication sampleof 401 knowledge workers were applied to analyse the above relations using OLS regression by SPSS PROCES. The results showed that the most critical factor...
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An analogue of the Pöschl–Teller anharmonic oscillator on an N-dimensional sphere
PublikacjaA Schr{\"o}dinger particle on an $N$-dimensional ($N\geqslant2$) hypersphere of radius $R$ is considered. The particle is subjected to the action of a force characterized by the potential $V(\theta)=2m\omega_{1}^{2}R^{2}\tan^{2}(\theta/2) +2m\omega_{2}^{2}R^{2}\cot^{2}(\theta/2)$, where $0\leqslant\theta\leqslant\pi$ is the hyperlatitude angular coordinate. In the general case when $\omega_{1}\neq\omega_{2}$, this is a model of...
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Anterior prefrontal EEG theta activities indicate memory and executive functions in epilepsy patients
PublikacjaObjective: Cognitive deficits are one of the most debilitating comorbidities in epilepsy and other neurodegenerative, neuropsychiatric, and neurodevelopmental brain disorders. Current diagnostic and therapeutic options are limited and lack objective measures of the underlying neural activities. In this study, electrophysiological biomarkers that reflect cognitive functions in clinically validated batteries were determined to aid...
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Anticancer drugs targeting topoisomerase II for antifungal treatment
PublikacjaFungal topoisomerase II (TopoII) has been identified as essential for viability. Thus, our research aimed to investigate the potential of fungal TopoII as a novel target for antifungal chemotherapy. We conducted studies on eleventh antitumor compounds targeting human topoisomerase II, either approved by the U.S. Food and Drug Administration (FDA) or currently under clinical trials to evaluate their potential for use in other therapeutic...
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Application of 3D scanning and computer simulation techniques to assess the shape accuracy of welded components
PublikacjaWhile traditional measurement methods prove to be insufficient when facing more complex shapes and intricate challenges, increasingly efficient solutions are emerging in their place. 3D scanners in particular exhibit versatility. They clearly represent a useful tool in many fields with diverse requirements; thus, it is advisable to explore further areas of their potential applications, e.g., in quality control or reverse engineering....
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Application of UV-VIS Spectroscopy and Machine Learning Methods in Glucosuria Diagnostics: A Phantom Study
PublikacjaIn this study, UV-VIS spectroscopy was used as a tool for detecting low glucose concentrations in urine. Measurements were performed on artificial urine samples and solutions with 0.1% and 0.2% glucose, covering both normal and pathological thresholds. Among the evaluated models, Random Forest reached 0.887for the 0.1% glucose sample, while Logistic Regression achieved 0.7796 for the 0.2% glucose sample,...
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Artificial Intelligence for Wireless Communications: the InSecTT perspective
PublikacjaThis paper presents an overview of how Artificial Intelligence (AI) and edge technology have been used to improve wireless connectivity in multiple industrial Use Cases (UCs) of the EU project “Intelligent Secure Trustable Things” (InSecTT). We present a brief introduction of the InSecTT framework for crossdomain architecture design, which targets UCs assisted by reusable and/or interoperable technical Building Blocks (BBs). These...
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ASSESSMENT OF THE GREENNESS OF MOLECULARLY IMPRINTED POLYMERS USED IN SAMPLE PREPARATION
PublikacjaIt is now widely accepted that the incorporation of molecularly imprinted polymers (MIPs) into sample preparation techniques has enabled unprecedented selectivity performance of analytical methods for the determination of a wide range of analytes in biological, food and environmental samples. However, according to the Principles of Green Chemistry and the subsequent Principles of Green Sample Preparation, it is clear that MIPs...
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Automatic Cleaning of Time Series Data in Rural Internet of Things Ecosystems That Use Nomadic Gateways
PublikacjaA serious limitation to the deployment of IoT solutions in rural areas may be the lack of available telecommunications infrastructure enabling the continuous collection of measurement data. A nomadic computing system, using a UAV carrying an on-board gateway, can handle this; it leads, however, to a number of technical challenges. One is the intermittent collection of data from ground sensors governed by weather conditions for...
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BEZPIECZEŃSTWO DZIECI W CYBERPRZESTRZENI KLUCZOWE ZAGADNIENIA I PRZEPISY PRAWNE
PublikacjaBezpieczeństwo dzieci w cyberprzestrzeni kluczowe zagadnienia i przepisy prawneOpracowanie eksperckie Marcin Niedopytalski W dobie powszechnej cyfryzacji, kiedy dostęp do internetu stał się nieodłącznym elementem życia codziennego, kwestia bezpieczeństwa dzieci w sieci nabiera szczególnego znaczenia. Z jednej strony obserwujemy korzyści płynące z edukacji online, swobodnego dostępu do informacji...
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Bistability and chaos in the discrete two-gene Andrecut-Kauffman model
PublikacjaWe conduct numerical analysis of the 2-dimensional discrete-time gene expression model originally introduced by Andrecut and Kauffman (Phys. Lett. A 367: 281–287, 2007). In contrast to the previous studies, we analyze the dynamics with different reaction rates α1 and α2 for each of the two genes under consideration. We explore bifurcation diagrams for the model with α1 varying in a wide range and α2 fixed. We detect chaotic dynamics...
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Born Twice: The Role of Social Media in Identity Redefinition after Sudden Disability
PublikacjaFrom being attacked by a shark to being stricken by illness, people who acquire disabilities later in life have unique lived experiences. There is, however, a commonality that binds them: the loss of a former identity and a rebirth into another life. They may also struggle with self-acceptance as they shun societal stigmas and perceived deviance from cultural norms. Through a netnographic study, we examine how identities are redefined...
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Calculations of Cross-Sections for Positron Scattering on Benzene
PublikacjaIn this work, we present a theoretical study on positron scattering by benzene molecules over a broad energy range (1–1000 eV). The aim of this work is to provide missing data from partial cross-sections for specific processes. In particular, calculations of cross-sections for direct ionization and electronic excitation were carried out for benzene molecules in the gas phase. An estimate for the cross-section for positronium formation...
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Characteristics Mode Analysis and Excitation of Orthogonal Modes on a Single Substrate for Wideband IoT Applications in the Millimeter Wave Band
PublikacjaThis paper presents the design of a circularly polarized millimeter-wave (mm-wave) metasurface (MTS) antenna. The Characteristics Modes Analysis (CMA) is employed to examine various modes within the unit-cell design of the proposed metasurface. Based on a thorough analysis, two orthogonal TM modes with a broadside radiation pattern were identified. These modes were then simultaneously excited on a single substrate using simple...
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Chemical composition and techno-functional properties of high-purity water-soluble keratein and its enzymatic hydrolysates
PublikacjaThis study compared the effectiveness of urea-containing and urea-free L-cysteine solutions in extracting high-quality feather keratin and evaluated commercial proteases for producing keratin-derived bioactive peptides. The urea-assisted extraction was crucial for achieving high structural integrity and yield of soluble keratin. The keratin isolate exhibited oil-holding capacity of 9.37 g/g, foaming capacity of up to 127 %, and...
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Chemical insight into pros and cons of coffees from different regions
PublikacjaThe main aim of this work was to study the chemical composition of eighteen ground coffees from different countries and continents with regard to the content of hazardous substances as radioactive elements (40K, 226Ra, 228Ra, 234U, 238U and 137Cs), metals, including heavy metals, aluminum and some microelements (V, Cr, Mn, Fe, Co, Ni, Cu, Zn) as well as substances that have a positive effect on human health and well-being (polyphenols,...
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CO2 capture through Direct-Contact Condensation in a spray ejector condenser aided by a cyclone or T-junction separators
PublikacjaThis dissertation explores the vital task of separating and purifying CO2 in post-combustion sections of gas power plants. It focuses on integrating spray or steam ejector condenser with cyclone or T-junction separators to enhance CO2 capture through direct-contact condensation (DCC). The study employs experimental, analytical, and numerical techniques to understand DCC mechanisms within SEC and optimize separator performance....
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Company culture matters! Knowledge-driven companies' way to innovations and sustainability
PublikacjaCompanies today aim to adapt to rapidly changing business environments by acquiring knowledge, developing dynamic capabilities, fostering market innovations, and ensuring sustainability. Achieving these goals requires a supportive company culture aligned with its structure and strategy. This study proves the critical role of company culture in sustainability based on a sample of 496 Polish knowledge workers, using structural equation...
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Control structures of Doubly-Fed Induction Generator connected to Current Source Converter
PublikacjaThe control of Doubly-Fed Induction Generator can be achieved through various techniques. At present, many works published in the literature show the application of Voltage Source Converter in conjunction with Doubly-Fed Induction Generator. Recently published articles rarely involve the operational characteristics and technical aspects of the Doubly-Fed Induction Generator - Current Source Converter systems. The dissertation presents...
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Cost-Efficient Behavioral Modeling of Antennas by Means of Global Sensitivity Analysis and Dimensionality Reduction
PublikacjaComputational tools, particularly electromagnetic (EM) solvers, are now commonplace in antenna design. While ensuring reliability, EM simulations are time-consuming, leading to high costs associated with EM-driven procedures like parametric optimization or statistical design. Various techniques have been developed to address this issue, with surrogate modeling methods garnering particular attention due to their potential advantages....
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Crisis Management in the Hospitality Industry Analyzed Through a Social Sustainability Focus on Male and Female Leadership Styles
PublikacjaHuman capital management's managerial practices during a crisis ensure the achievement of main strategic objectives and result in long-term values, such as organizational learning, resilience, innovation, and business flexibility. Therefore, this study considers the social sustainability perspective in the hospitality industry as a critical aspect of crisis management. It specifically...
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Declarative ship arenas under favourable conditions
PublikacjaAccording to maritime regulations, a collision-avoidance action shall be taken at an “ample time” while strict interpretation of this term is ambiguous. Evasive manoeuvres, executed by marine navigators on a daily basis, are usually carried out well in advance, while the distance at which they decide to perform such a manoeuvre is mostly subjective and results, e.g., from the navigator's seagoing experience. A proper understanding...
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Decoding Customer Experience: A Comparative Analysis of Electric and Internal Combustion Vehicles in the U.S. Market Through Structured Topic Modeling
PublikacjaAmid global environmental challenges, the transition from internal combustion vehicles (ICVs) to electric vehicles (EVs) is a priority for governments and automobile manufacturers. This shift requires a deep understanding of consumer preferences and evolving adoption trends. Existing research highlights critical gaps, such as the lack of comparative studies analyzing EVs and ICVs’ consumer-perceived value and their evolution over...
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Deep eutectic solvent enhances antibacterial activity of a modular lytic enzyme against Acinetobacter baumannii
PublikacjaIn this study, we evaluated the combined effect between MLE-15, a modular lytic enzyme composed of four building blocks, and reline, a natural deep eutectic solvent. The bioinformatic analysis allowed us to determine the spatial architecture of MLE-15, whose components were bactericidal peptide cecropin A connected via a flexible linker to the cell wall binding domain (CBD) of mesophilic 201ϕ2 − 1 endolysin and catalytic domain...
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Deep eutectic solvent-induced coacervation in micellar solution of alkyl polyglucoside surfactant: Supramolecular solvent formation and application in food analysis
PublikacjaThe number of deep eutectic solvents were investigated to induce coacervation and cause phase separation in the micellar solution of the alkyl polyglucoside C8–C10. Three fatty acids were selected as hydrogen bond donors namely hexanoic acid, heptanoic acid, and octanoic acid, while quaternary ammonium salts and a monoterpenoid thymol were used as hydrogen bond acceptors to obtain deep eutectic solvents. The precursors of the deep...
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Degradation of dicamba – a persistent herbicide - by combined application of formic acid and UV as an advanced reduction process
PublikacjaThe degradation of dicamba as a persistent herbicide was studied with the combined application of UV and formic acid (FA) as a novel advanced reduction process (ARP). The effects of key parameters of FA concentration, dissolved organic matter, and inorganic anions were studied. A 97 % degradation and 94 % dechlorination of dicamba were obtained through the combination of UV and FA (UV-FA) at a dicamba concentration of 0.023 mM...
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Design and Validation of A 30 GHz 8×8 Slot Antenna Array with Ridge Waveguide Pins/Holes Layers
PublikacjaThis paper presents an 8×8-element slot antenna array optimized for 30 GHz band applications, achieving high gain, wide impedance bandwidth, and high efficiency. The array employs a pin/hole-based design, which enables a compact structure and reduces fabrication complexity and cost, as it eliminates the need for electrical contact between its three primary layers: the metal radiating slot plate, a sub-array cavity layer, and a...
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Development of a High-Sensitivity Triple-Band Nano-Biosensor Utilizing Petahertz Metamaterials for Optimal Absorption in Early-Stage Leukemia Detection
PublikacjaThis research focuses on designing a novel miniaturized biosensor for early-stage detection of leukemia. The proposed sensor operates in the low Petahertz (PHz) range. The primary prerequisites for the development process include multi-band operation, compact physical size, near-perfect absorption at resonant frequencies, and insensitivity to the angle of incidence. These features are crucial for ensuring high-performance operation...
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Development of dual nozzle slurry extrusion 3D printer by integrating material extrusion and photopolymerization for the fabrication of engineered ceramics
PublikacjaThis research focuses on developing a dual-nozzle slurry-based extrusion 3D printer capable of fabricating intricate zirconia structures. The designed 3D printer combines material extrusion and photopolymerization technologies to improve material diversity, precision, and cost-effectiveness. The 3D printer design incorporates ultraviolet curing to instantly cure extruded zirconia slurry thereby, eliminating the need for a step-wise...
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Diagnosis of marine internal combustion engines by means of rapidly variable temperature and composition of exhaust gas as an alternative or support for currently used diagnostic methods
PublikacjaThe article points out relevance of parametric diagnostics of ship engines and analyzes the state of research in this field. A method is proposed for diagnosing engine systems on the basis of rapidly variable exhaust temperature while measuring its composition. A method for determining diagnoser tools from the signal within one engine cycle and mathematical and statistical treatment of test results is presented. The products of...
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Differential evolution-optimized gold nanorods for enhanced photothermal conversion
PublikacjaNoble metallic nanoparticles (NPs) have shown great potential in the field of sustainable energy. Gold nanorods (AuNRs), known for their size-dependent optical and electrical characteristics, are strong candidates for various applications, particularly in solar energy conversion. Additionally, AuNRs are well-established nanomaterials in precision medicine. In this paper, we optimize the shape and size of AuNRs to maximize light-to-heat...
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Dynamic anaerobic digestion-based biorefineries for on-demand renewable energy and bioproducts in a circular bioeconomy
PublikacjaAnaerobic digestion (AD) is an important biotechnology for treating biodegrad- able residues and producing bioenergy, yet its full potential remains untapped. We investigate a two-phase AD system for biorefinery applications, producing valuable bioproducts, such as volatile fatty acids (VFAs) and biogas, from grass feedstock. We introduce a demand-driven operational approach to match mar- ket conditions, while minimising water...
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Effect of process parameters on properties of Mn1.5CuFe0.5O4 spinel oxide coatings deposited by spray pyrolysis method
PublikacjaOne of the critical issues in the lifetime of metallic interconnects is related to their high oxidation rate and Cr diffusion, which negatively affect their performance. In the present study, a novel Fe modified Mn–Cu spinel oxide with the chemical composition of Mn1.5CuFe0.5O4 as protective coating was deposited on the surface of Crofer 22 APU and alumina by the spray pyrolysis method. The effects of different deposition conditions...
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Effects of aggregate crushing and strain rate on fracture in compressive concrete with a DEM-based breakage model
PublikacjaW tym artykule zbadano, w jaki sposób kruche kruszywa wpływają na mezoskopowe zachowanie dynamiczne betonu w warunkach jednoosiowego ściskania. Przeprowadzono obszerne dynamiczne obliczenia dwuwymiarowe (2D), aby zbadać wpływ kruszenia kruszywa i szybkości odkształcania na dynamiczną wytrzymałość betonu i wzory pęknięć. Wykorzystując model pękania oparty na DEM, beton symulowano jako materiał czterofazowy składający się z kruszywa,...
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Efficacy of modal curvature damage detection in various pre-damage data assumptions and modal identification techniques
PublikacjaThe efficacy of modal curvature approach for damage localization is discussed in the paper in the context of input data. Three modal identification methods, i.e., Eigensystem Realization Algorithm (ERA), Natural Excitation Technique with ERA (NExT-ERA) and Covariance Driven Stochastic Subspace Identification (SSI-Cov), and four methods of determining baseline data, i.e., real measurement of the undamaged state, analytical function,...
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Electrospun Fibers from Biobased and Recycled Materials for Indoor Air Quality Enhancement
PublikacjaAir filters are crucial components of building ventilation systems. Compared to conventional air filter media like glass fibers and melt-blown fibers, electrospinning membranes are more efficient for capturing various pollutants due to the smaller pores present on the structure. In this paper, activated carbon filters were prepared with eco-friendly polylactic acid (PLA) and microcrystalline cellulose (MCC) using electrospinning...
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EMF Signature Analysis in a Marine-Type Brushless Synchronous Generator for Online Fault Detection
PublikacjaThe objective of the paper is to investigate the application of the current signature analysis type approach for the online diagnosis of a marine-type Brushless Synchronous Generator (BSG). The system’s diagnostic would be done using an automated test procedure when the generator comes online or offline. The analysis of the measured electromotive force waveform (EMF) is used for fault detection. The paper’s main contribution...
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Energy potential and economic viability of small-scale wind turbines
PublikacjaSmall-scale wind turbines (SWTs) have the potential to complement residential PV systems, but their feasibility is highly dependent on local wind conditions, particularly at low elevations where wind resources exhibit high spatial and temporal variability. This study evaluates SWT potential in Poland (Central Europe) using hourly wind speed measurements over six years from 269 gauging stations. A generic power curve is applied...
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Enhanced Gain and Isolation Dual-Band Dual-Port MIMO Antenna with Integrated Lens for Millimeter-wave 5G Internet-of-Things Applications
PublikacjaThis paper proposes a dual-band dual-port Multiple Input Multiple Output (MIMO) antenna with enhanced gain and port isolation for 5G millimeter-wave (mm-wave) Internet of Things (IoT) applications. The gain enhancement is achieved using a 3D-printed dielectric lens integrated with the antenna, whereas port isolation is improved using a novel 2D compact metamaterial incorporated between the MIMO elements. The proposed integrated...
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Enhanced sorption of inhibitory compounds from fermentation broth using a MOF@pseudo-DES composite
PublikacjaThe increase in biorefinery processes underscores the need for effective biofuel generation; nevertheless, inhibitors such as hydroquinone (HQ), 5-hydroxymethylfurfural (HMF), furfural (FF), and vanillin (VAN) resulting from biomass degradation impede microbial growth and process efficiency. Herein, a deep eutectic solvent (DES)-like substance was in-situ generated on the surface of NH2-UiO-66 via a post-synthetic coating process...
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Enhancing the bioconversion rate and end products of black soldier fly (BSF) treatment – A comprehensive review
PublikacjaFood security remains a pressing concern in the face of an increasing world population and environmental challenges. As climate change, biodiversity loss, and water scarcity continue to impact agricultural productivity, traditional livestock farming faces limitations in meeting the growing global demand for meat and dairy products. In this context, black soldier fly larvae (BSFL) have emerged as a promising alternative for sustainable...
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Enhancing the fracture performance of cementitious composites through synergistic integration of graphene with polyolefin and polyvinyl alcohol fibres
PublikacjaPolyvinyl alcohol fibre (PVA) and polyolefin fibre (PO) are utilised in engineering cementitious composites (ECCs) due to their excellent crack-bridging capabilities, durability, ductility and energy absorption capacity. However, their combined effects on crack propagation mechanism, especially when combined with nano-reinforcement, remain underexplored. Recently, graphene nanoplatelets (GNPs) have emerged as promising nano-reinforcement...