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  • A review on hydrophobic electrospun nanofibers-based materials and membranes for water treatment: Challenges, outlook, and stability
    • Farooque Janjhi
    • Imamdin Chandio
    • Dahar Janwery
    • Vahid Vatanpour
    • Roberto Castro Munoz
    2025 SEPARATION AND PURIFICATION TECHNOLOGY

    Membrane technology is well recognized as a dependable means of supplementing the availability of potable water through processes such as water purification and desalination. Electrospun nanofiber membranes have garnered significant attention because of their advantageous features, including a greater specific surface area, increased porosity, reduced thickness, and popularity. Consequently, ENMs have emerged as an up-and-coming contender in several applications. The various methods employed for fabrication involve inorganic deposition, polymer coating, and interfacial polymerization. Electrospun nanofiber membranes’ efficacy in removing diverse water pollutants, including heavy metals, dyes, and antibiotics, has been exceptional. The enhancement of polymer membrane performance can be achieved through the precise adjustment of polymer structure, manipulation of surface properties, and reinforcement of total membrane porosity. The study investigates the fundamentals of electrospun nanofibers and their utilization in electrospun nanofibrous membranes and composites for environmental remediation applications. The final section discusses the opportunities and significant challenges concerning the application of engineered nanomaterials in the water treatment sector. The advancement of engineered nanomaterials is anticipated to facilitate the growth and application of multiple industries, including water treatment and sustainability.

  • AI-Driven Sustainability in Agriculture and Farming
    • Julian Szymański
    • Karolina Nurzyńska
    • Paweł Weichbroth
    2025

    In this chapter, we discuss the role of artificial intelligence (AI) in promoting sustainable agriculture and farming. Three main themes run through the chapter. First, we review the state of the art of smart farming and explore the transformative impact of AI on modern agricultural practices, focusing on its contribution to sustainability. With this in mind, our analysis focuses on topics such as data collection and storage, AI algorithms in agriculture, and optimization areas. We also present recent advances in agricultural technology and equipment used to develop a wide range of production methods used by modern farmers. We discuss agri-environmental monitoring, which refers to the real-time or periodic monitoring and assessment of environmental components in agricultural production. Specifically, five types of environmental monitoring are presented, viz: air quality monitoring, water sampling and analysis, noise level testing, soil quality testing, and microbial monitoring. We also discuss weather forecasting, one of the most challenging scientific endeavors. The chapter concludes with applications for monitoring and managing environmental impacts and explores future trends and innovations based on cutting-edge research and emerging technologies.

  • Development of an asymmetric cellulose acetate-ionic liquid P6,6,6,14[PHOS] gel membrane for the perstraction of succinic acid from a model fermentation solution of yarrovia lipolytica
    • Elsie Zurob
    • Esteban Quijada-Maldonado
    • Roberto Castro Munoz
    • Julio Romero
    • Andrea Plaza
    • René Cabezas
    2025 SEPARATION AND PURIFICATION TECHNOLOGY

    This study introduces a novel approach to separate succinic acid (SA) from fermentation mixtures using an asymmetric membrane based on the gelation of the ionic liquid [P6,6,6,14][PHOS] coated with two layers of cellulose acetate. The membrane was designed to explore the synergistic effect of polymer-ionic liquid interfaces according to the solution-diffusion theory. The gelation of the ionic liquid was achieved using 12-hydroxystearic acid at a concentration of 1.5%, allowing the use of ionic liquid gels as new materials for the generation of membranes. The perstraction performance of the membrane was evaluated over 5 h at two different temperatures (25°C and 37°C), with an initial feed solution concentration of 50 kg m−3 for SA and glycerol and pure water as a receiving phase., Several flow rates and phase-volume ratios were studied anda mass transfer model based on the resistance-in-series theory was assessed to understand the behavior of each mass transfer stage considering the distribution in each interphase. Interestingly, optimal perstraction results were obtained at 37°C, with an average transmembrane flux of 0.22 kg m-2h−1 for SA, an extraction percentage of 43.1% for SA and 0.7% for glycerol, and a SA/glycerol selectivity of 54.98. Besides presenting a novel composite membrane, this study reports pioneering perstraction outcomes, highlighting its potential as an innovative SA separation strategy and structured new materials for selective extractions.

  • Gold(III) complexes with chloride and cyanopyridines: Facilitated hydrolysis of nitrile ligand to amide and antibacterial activity
    • Maciej Ejnik
    • Piotr Bruździak
    • Karolina Gutmańska
    • Anna Ciborska
    • Magdalena Malik
    • Dietrich Gudat
    • Anna Brillowska-Dąbrowska
    • Anna Dołęga
    2025 SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY

    A range of novel simple gold(III) compounds has been synthesized in their monocrystalline form, including two previously unknown chloro-complexes of Au3+ with 2-cyanopyridine or 3-cyanopyridine, respectively. Our investigations have revealed the intricate nature of the reaction between 2-cyanopyridine and tetrachloroauric acid, yielding at least three distinct products. The main product, obtained in high yield, is a salt featuring a tetrachloroauric anion and a pyridinium cation stabilized by a hydrogen bond to a further 2-cyanopyridine molecule. Moreover, we observed the in-situ formation of a 2-cyanopyridine-AuCl3 complex, which undergoes hydrolysis of the nitrile bond to yield a picolinamide-Au(III) complex. The complexes were characterized by IR and Raman spectroscopies, NMR spectroscopy, and single-crystal XRD studies. Additional computational studies were conducted to explain unusual spectral features, the observed disparities in the complexation reactions of the three isomeric cyanopyridine ligands and the distinct reactivity of the complex with 2-cyanopyridine. Based on these studies, we propose a mechanism for the catalyzed hydrolysis of the nitrile bond within the Au(III) complex. Finally, we assessed the antimicrobial efficacy of the synthesized gold(III) complexes against a spectrum of bacteria and fungi.

  • Monitoring of absorptive model biogas purification process using sensor matrices and gas chromatography
    • Edyta Słupek
    • Dominik Dobrzyniewski
    • Patrycja Makoś-Chełstowska
    • Bartosz Szulczyński
    • Jacek Gębicki
    2025 MEASUREMENT

    This study examined the process of purifying model biogas using a new type of absorbent based on a Deep Eutectic Solvent (DES) and a commercially available absorbent (Genosorb) to remove acetone, toluene, and cyclohexane. The main aim of the research was to control the purification efficiency using gas chromatography (GC) and an alternative method based on sensor matrices (SM). As a result of comparing the multidimensional SM signals with the GC result, the lowest difference between SM and GC (3.69%) was achieved with the DES. When using Genosorb, the differences between the methods were slightly more pronounced, reaching 10.26%. The studies also confirmed that SM results showed significant agreement, accuracy, precision, and equivalence compared to GC results. Nowadays, the literature has not reported this issue. The presented research fills the current gap in the literature and contributes to the development of knowledge in the practical application of SM.

  • 3D-Breast System for Determining the Volume of Tissue Needed for Breast Reconstruction
    • Gabriela Małyszko
    • Julia Czałpińska
    • Andżelika Janicka
    • Katarzyna Ostrowska
    • Mariusz Kaczmarek
    2024

    3D imaging systems can be used to effectively determine breast volumes for surgical applications. This article presents methods for surface reconstruction and volume determination based on the point cloud created by 3D imaging. Such a system would be used to accurately estimate breast volume in patients classified for breast reconstruction surgery at plastic surgery centers. To develop such a system, various methods of determining volume, based on images from the Intel D435i camera, were tested. In addition, an application and a measuring station tailored to clinical needs were developed

  • 9,10-Dioxoanthracenyldithiocarbamates effectively inhibit the proliferation of non-small cell lung cancer by targeting multiple protein tyrosine kinases
    • Mateusz Olszewski
    • Maryna Stasevych
    • Viktor Zvarych
    • Natalia Maciejewska
    2024 Pełny tekst JOURNAL OF ENZYME INHIBITION AND MEDICINAL CHEMISTRY

    Anthraquinones have attracted considerable interest in the realm of cancer treatment owing to their potent anticancer properties. This study evaluates the potential of a series of new anthraquinone derivatives as anticancer agents for non-small-cell lung cancer (NSCLC). The compounds were subjected to a range of tests to assess their cytotoxic and apoptotic properties, ability to inhibit colony formation, pro-DNA damage functions, and capacity to inhibit the activity of tyrosine kinase proteins (PTKs). Based on the research findings, it has been discovered that most active derivatives (i84, i87, and i90) possess a substantial capability to impede the viability of NSCLC while having mostly a negligible effect on the human kidney cell line. Moreover, the anthraquinones displayed pro-apoptotic and genotoxic attributes while blocking the phosphorylation of multiple PTKs. Collectively, our findings indicate that these derivatives may demonstrate promising potential as effective anticancer agents for lung cancer treatment.

  • A 0.5 V Nanowatt Biquadratic Low-Pass Filter with Tunable Quality Factor for Electronic Cochlea Applications
    • Jacek Jakusz
    • Waldemar Jendernalik
    2024 Pełny tekst Electronics

    A novel implementation of an analogue low-power, second-order, low-pass filter with tunable quality factor (Q) is presented and discussed. The filter feature is a relatively simple, buffer-based, circuit network consisting of eleven transistors operating in a subthreshold region. Q tuning is accomplished by injecting direct current into a network node, which changes the output resistance of the transistors and, as a result, modifies the filter network’s loss, and thus its Q. Q tuning is independent of a filter cut-off frequency (ω0). The filter, with a nominal ω0 of 1 kHz, was fabricated using a 0.18 μm CMOS technology, and features a Q range of 2–11, power consumption of up to 52 nW, and a 59 dB dynamic range when using a 0.5 V supply. The ω0 can be tuned from 0.5 to 2.5 kHz using a traditional method by changing the transistor transconductances, but this process partially affects the quality factor.

  • A Closed Bipolar Electrochemical Cell for the Interrogation of BDD Single Particles: Electrochemical Advanced Oxidation
    • Anna Dettlaff
    • Joshua Tully
    • Georgia Wood
    • Deep Chauhan
    • Ben Breeze
    • Lijiang Song
    • Julie V. Macpherson
    2024 Pełny tekst ELECTROCHIMICA ACTA

    A closed bipolar electrochemical cell containing two conductive boron-doped diamond (BDD) particles of size  250 – 350 m, produced by high-pressure high-temperature (HPHT) synthesis, has been used to demonstrate the applicability of single BDD particles for electrochemical oxidative degradation of the dye, methylene blue (MB). The cell is fabricated using stereolithography 3D printing and the BDD particles are located at either end of a solution excluded central channel. Platinum wire electrodes placed in each of the two outer solution compartments are used to drive electrochemical reactions at the two BDD particles, which, under bipolar conditions do not require direct electrical connection to a potential source. Experiments using ultra high-performance liquid chromatography coupled with mass spectrometry (UHPLC-MS) show that the anodic pole BDD particle is able to electrochemically remove > 99% of the dye (originally present at 1  10-4 M) to undetectable UHPLC-MS products in 600 s. Monitoring of the time dependant change in MB peak area, from the UHPLC chromatograms, enables a pseudo first order rate constant of 0.54 min-1 to be determined for MB removal. Given the large scale at which such particles can be produced (tonnes), such data bodes well for scale up opportunities using HPHT-grown BDD particles, where the particles can be assembled into high surface area electrode formats.

  • A closer look at how the dispersive liquid–liquid microextraction method works. Investigation of the effect of solvent mixture composition on the quality and stability of the cloudy state
    • Serhii Zaruba
    • Michaela Ovšonková
    • Patrycja Makoś-Chełstowska
    • Vasil Andruch
    2024 Pełny tekst Frontiers in Chemistry

    The dispersive liquid–liquid microextraction (DLLME) is one of the most popular miniaturized extraction procedures. In this paper, the degree of dispersion and dispersion stability were studied with the aim to assess the correlations of these parameters with efficiency for the selected analytical application. The dependence between the degree of dispersion (cloudy state quality) and its stability obtained by various emulsification procedures, such as solvent-assisted emulsification (using various dispersive solvents) and mechanical emulsification (using auxiliary energies), is investigated and discussed. It was found out that the degree of dispersion depends on the type of emulsification procedure and decreases in the series: solvent-assisted (SA-) = ultrasound-assisted (UA-) > air-assisted (AA-) > vortex-assisted (VA-) emulsification. The emulsion stability depends on the degree of dispersion and there were 1810 and 2070 s for the most effective emulsification procedures, such us solvent-assisted and ultrasound-assisted emulsification, respectively. A comparison between the sensitivity of the analytical methods (using spectrophotometric determination of the anionic surfactants) and the degree of dispersion have been made. The sensitivity of the methods was ranked as follows: DLLME > UA-LLME > VA-LLME > AA-LLME.

  • A comparative analysis of methods and tools for low impact development (LID) site selection
    • Khansa Gulshad
    • Michał Szydłowski
    • Andaleeb Yaseen
    • Rana Waqar Aslam
    2024 Pełny tekst JOURNAL OF ENVIRONMENTAL MANAGEMENT

    The site selection for Low Impact Development (LID) practices is a significant process. It affects the effectiveness of LID in controlling stormwater surface runoff, volume, flow rate, and infiltration. This research paper presents a comprehensive review of various methods used for LID site selection. It starts by introducing different methods and tools. Three main methods: index-based methods, GIS-based multi-criteria decision analysis (MCDA), and multi-criteria models and tools, are discussed in detail. A comparative analysis of these methods is then conducted based on ten different criteria. These criteria include the number of variables, data properties, the scale of analysis, benefits maximization approach, multi-attribute decision analysis, user-friendliness, community and stakeholder participation, and the validation methods. This comparison reveals limitations in each method. These include inadequate data availability and quality, lack of evaluation methods, comprehensive assessment criteria and spatial explicitness. These challenges underscore the need for future research to prioritize spatial clarity, broaden criteria, improve data quality through standardization, incorporate field visits and remote sensing for robust results, integrate big data, and develop web-based, open-source tools for enhanced accessibility. These key strategies provide valuable insights for advancing LID site selection methods.

  • A comparative analysis of numerically simulated and experimentally measured static responses of a floating dock
    • Jianan Zhang
    • Xueliang Wen
    • Aleksander Kniat
    • Muk Chen Ong
    2024 Ships and Offshore Structures

    Two numerical methods, dynamic and static analyses, are proposed to calculate the static responses of a floating dock under different ballast water distributions. Model-scale experimental tests were conducted to compare with these numerical methods. The dynamic analysis includes a 6-degree-of-freedom (6-DOF) model, a hydrostatic force model and a hydrodynamic force model to simulate the dock's freely floating processes. The dock's equilibrium position is identified when the difference in the dock’s motions between two successive time steps is below a specified tolerance value. In the static analysis, the static equilibrium equations in draught, heel, and trim are solved using the Newton-Raphson method. Both dynamic and static results of the draughts at the four corners, heel, and trim are in good agreement with the corresponding experimental results, which shows the reliability of the proposed numerical methods. Moreover, the static analysis exhibits quicker convergence, requiring fewer iteration steps than the dynamic analysis.

  • A Comprehensive Approach to Azo Dichlorotriazine Dye Treatment: Assessing the Impact of Physical, Chemical, and Biological Treatment Methods through Statistical Analysis of Experimental Data
    • Gamal K. Hassan
    • Montaser Y. Ghaly
    • Ghada E. Ahmed
    • Rehab M. Mohamed
    • Heba A. El-Gawad
    • Przemysław Kowal
    • Hussein Al-Hazmi
    • Ahmed A. Afify
    2024 Water

    This exploration investigates integrated treatment systems combining advanced oxidation processes (Fenton and photo-Fenton) with biological methods for the effective elimination of stubborn organic compounds in simulated textile wastewater composed of azo Dichlorotriazine dye. A comprehensive optimization of key process factors including catalyst dosage, hydrogen peroxide quantity, irradiation duration, etc. was systematically conducted for both Fenton and photo-Fenton processes to realize maximum COD and color removal. Under ideal conditions (0.4 g/L photocatalyst, 1 mL/L H2O2, and 75-Watt UV intensity for 60 min), the photo-Fenton process realized 80% COD elimination and complete decolorization, meeting industrial discharge limits without needing extra biological treatment. Statistical models correlating process parameters to treatment efficiency were developed, giving important design insights. For Fenton, effluent COD exceeded discharge thresholds, so a post-biological treatment using activated sludge was essential to comply with regulations. This integrated Fenton–biological scheme utilizes synergism between chemical and biological processes for enhanced overall treatment. Notable economic benefits were achieved by photo-Fenton over conventional UV-only and UV/H2O2 methods regarding energy consumption and operating costs. Overall, this pioneering work successfully proves integrated advanced oxidation–biological systems as a superior, sustainable alternative to traditional techniques for economically removing obstinate pollutants, such as azo Dichlorotriazine dye, as it is a simulated textile wastewater treatment used to satisfy environmental standards.

  • A Comprehensive Review: Applications of the Kozeny–Carman Model in Engineering with Permeability Dynamics
    • Maryam Rehman
    • Muhammad Bilal Hafeez
    • Marek Krawczuk
    2024 ARCHIVES OF COMPUTATIONAL METHODS IN ENGINEERING

    In this review article, we investigate the dynamic nature of the Kozeny–Carman Model concerning permeability and its application in engineering contexts. Providing insights into the changing dynamics of permeability within mining, petroleum, and geotechnical engineering, among other engineering applications. While some are complex and require additional modifcations to be applicable, others are simple and still function in specifc situations. Therefore, having a thorough understanding of the most recent permeability evolution model would help engineers and researchers in fnding the right solution for engineering issues for prospects. The permeability evolution model Kozeny–Carman (KC) put forth by previous and current researchers is compiled in this paper, with a focus on its features and drawbacks

  • A COMPREHENSIVE REVIEW OF LIFE CYCLE ASSESSMENT AND ENERGY EFFICIENCY IN 3D PRINTING FOR CONSTRUCTION: CURRENT STATE, BENEFITS, LIMITATIONS, AND FUTURE OUTLOOK
    • Semahat Merve Top
    • Jan Cudzik
    2024 Pełny tekst Journal of Green Building

    The agenda of Industry 4.0 strongly affects design and construction at all its phases, and three-Dimensional Printing (3DP) is an essential part of it. The emerging technology has the potential to become a more valid and accepted form of construction. This research is based on a literature review regarding the relationships between the concepts of Life Cycle Assessment (LCA) and energy efficiency for 3DP in construction research to understand the developments. Systematic bibliometric and scientometric analyses are used as data analysis techniques to make a detailed comparison. The comparison allowed for assessing and determining the current state, benefits, limitations, and future outlook. Current research is based on insights examining materials first (80%), followed by walls (15%), buildings (11%), and 3DP technology (6%). The findings highlight that 3DP technology offers significant advantages in terms of time efficiency, reliability, ecological impact, and sustainability within the construction industry. However, several challenges, such as the complexity of material mixture content design, the lack of standardized 3DP materials and codes, and the limited availability of experts in the field, prevent its widespread adoption. Further advancement of 3DP requires the development of standards, policies, training and materials for its full implementation in the construction industry.

  • A comprehensive review on economic, environmental impacts and future challenges for photovoltaic-based electric vehicle charging infrastructures
    • Haseeb Rashid
    • Liu Ming Hua
    • Lyu Guanghua
    • Rija Hasan
    • Abdulrahman AlKaseem
    • Aqsa Ali
    • Syed Hadi Hussain Shah
    • Shoaib Shaikh
    • Arsalan Muhammad Soomar
    • Piotr Musznicki
    2024 Frontiers in Energy Research

    In this paper, a comprehensive review of the impacts and imminent design challenges concerning such EV charging stations that are based on solar photovoltaic infrastructures is presented, which is based on state-of-the-art frameworks for PV-powered charging stations and the latest case studies. The main factors that are targeted in this review are the management of an EV charging system that is a composite of PV and public grid, as well as a charging system business model that can affect consumer behavior by charging at different rates and the best design infrastructure for a PV electric vehicle charging services. The economic, environmental, and social impacts caused by the installation of PVdriven charging infrastructures are also compared. Moreover, the framework for recently emerging vehicle-to-grid and vehicle-to-home services, as well as the integration of these frameworks, is discussed. Finally, survey results for future EV demand and its public acceptance are presented. Appertaining to these issues, the case studies highlight that EV transportation between parking lots and charging stations is necessary to make the best use of the available charging stations. Statistically, in this study, it was inferred that there are no limitations on the amount of EV battery capacity that can be stored, and users of EVs can charge in both slow and fast modes. Furthermore, V2G systems are not suitable for widespread industrial use. Moreover, finding solutions and overcoming numerous obstacles remain unaddressed issues, and the size of the EV industry must reach a certain level to make profitable sales of V2B, V2H, V2G, and other V2X systems. The collected statistics indicate that although respondents generally have a favorable opinion of the mobility applications powered by photovoltaic cells, it seems unlikely that they will use them anytime soon.

  • A dissimilar welded joint of grade 92 steel and AISI 304L steel obtained using IN82 buttering and IN617 fller: relationship of microstructure and mechanical properties
    • Hardik Sanjay Surkar
    • Amit Kumar
    • Sachin Sirohi
    • Shailesh M. Pandey
    • Aleksandra Świerczyńska
    • Dariusz Fydrych
    • Chandan Pandey
    2024 Archives of Civil and Mechanical Engineering

    Unfavourable operating conditions of equipment in the energy industry resulting from high-temperature loads determine the need to use special materials and technological solutions, including welding procedures. In this article, buttering using IN82 (ERNiCr-3) consumables was proposed as a method to improve the weldability of grade 92 steel joined by the gas tungsten arc welding (GTAW) process with AISI 304L (IN617 fller). The microstructural characterization of samples was carried out using an optical microscope, scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy. The welded joint was further characterized by hardness, tensile (room temperature and at 620 °C temperature) and impact tests. Additionally, the fracture surfaces of tensile and impact tests were studied by SEM. Despite the confrmation of the difusion of alloying elements and signifcant changes in their concentration, which indicates the formation of Ti and Nb-rich phases, no welding imperfections were detected and favourable joint structures and acceptable properties were obtained. In particular, this concerns the limitation of the formation of brittle structures and the elimination of the untempered martensitic layer. At the same time, there was a signifcant decrease in the maximum hardness of heat-afected zone (HAZ) on the grade 92 steel side to a relatively low value of 310 HV, and a minimum tensile strength criterion of 600 MPa was achieved with a simultaneous increase in ductility (35% elongation) of the joint. Comparatively, when compared to a non-buttered welded joint, the joint produced with a buttering layer exhibited an increase in the elongation and impact toughness of the welded joint without any compromise in ultimate tensile strength (Sut). The fracture surface of tensile and impact-tested specimens was also characterized using SEM/EDS. Summarizing all the results, it can be concluded that the proposed GTAW procedure of grade 92 and 304L steels can be used in extreme working conditions, in ultra-supercritical power units or the petrochemical and chemical industries.

  • A Finite Element Approach for Wave Propagation in Elastic Solids
    • Arkadiusz Żak
    2024

    This book focuses on wave propagation phenomena in elastic solids modelled by the use of the finite element method. Although the latter is a well-established and popular numerical tool used by engineers and researchers all around the word the process of modelling of wave propagation can still be a challenge. The book introduces a reader to the problem by presenting a historical background and offering a broad perspective on the development of modern science and numerical methods. The principles of wave phenomena are clearly presented to the reader as well as the necessary background for understanding the finite element method, which is the following chapter of the book is viewed from the modeller point-of-view. Apart from the principles the book also addresses more advanced topics and problems including the use of the spectral-finite element method, the spline-based finite element method as well as the problems of undesired and hidden properties of discrete numerical models.

  • A framework for risk matrix design: A case of MASS navigation risk
    • Cunlong Fan
    • Jakub Montewka
    • Di Zhang
    • Zhepeng Han
    2024 ACCIDENT ANALYSIS AND PREVENTION

    Risk matrix, a tool for visualizing risk assessment results, is essential to facilitate the risk communication and risk management in risk-based decision-making processes related to new and unexplored socio-technical systems. The use of an appropriate risk matrix is discussed in the literature, but it is overlooked for emerging technologies such as Maritime Autonomous Surface Ships (MASS). In this study, a comprehensive framework for developing a risk matrix based on fuzzy Analytic Hierarchy Process (AHP) is proposed. In this framework, a linear function is defined where the risk index is treated as a response variable, while the probability and consequence indices are explanatory variables, with weights of these two indices representing their importance on given risk level. This significance is assessed by experts and quantified using AHP in interval type 2 fuzzy environment. A continuous risk diagram is then created and converted into a risk matrix that can be improved. To verify the feasibility of the proposed framework, a risk matrix is designed in the context of MASS grounding. The results show that the proposed approach is feasible. Our discussion results can provide new insights for the design of risk matrices and promote the management of MASS navigational risks.

  • A framework to analyse the probability of accidental hull girder failure considering advanced corrosion degradation for risk-based ship design
    • Krzysztof Wołoszyk
    • Floris Goerlandt
    • Jakub Montewka
    2024 RELIABILITY ENGINEERING & SYSTEM SAFETY

    Ship’s hull girder failure could result from maritime accident that can cause human life loss, environmental disaster, and major economic impacts. In risk-based ship design paradigm, accounting for rare phenomena (e.g. ship-ship collision or grounding) is important to provide safe and durable structure. In-service corrosion-induced hull degradation should be considered at the design stage, as it can significantly affect structural strength. The current study presents a novel framework to estimate the probability of ship hull girder failure, accounting for novel corrosion modelling techniques and accidental damage. The associated uncertainties are considered using statistical sampling from evidence-based distributions. A state-of-the-art deterministic model for ultimate strength calculation is applied using Monte Carlo simulation approach, resulting in the probability of hull failure through a reliability assessment. Wave and still-water bending moments are considered random variables. Two case studies of tanker ships with varying sizes are executed to show the applicability of the proposed framework. The results indicate that proper consideration of corrosion is of high importance, as ageing can significantly increase the probability of failure if accidental damage happens. Therefore, whereas future research and model refinement are discussed, the presented framework can serve for risk-based ship design tool and assess existing structures’ safety.

  • A gap waveguide-based mechanically reconfigurable phase shifter for high-power Ku-band applications
    • Ali Farahbakhsh
    • Davood Zarifi
    • Michał Mrozowski
    2024 Scientific Reports

    This paper presents a novel design of a low-loss, reconfgurable broadband phase shifter based on groove gap waveguide (GGW) technology. The proposed phase shifter consists of a folded GGW and three bends with a few pins forming the GGW and one bend attached to a movable plate. This movable plate allows for adjustments to the folded waveguide length, consequently altering the phase of electromagnetic waves. The advantage of GGW technology is that it does not require electrical contact between diferent parts of a structure. Therefore, it enables the moving parts to slide freely without electromagnetic energy leakage, resulting in improved insertion loss in high-power applications. In addition, in the proposed design, the position of the input and output waveguide ports of the phase shifter remains fxed, which is advantageous from a practical point of view. As shown by measurement and simulation results, there is nearly 37% impedance bandwidth with the highest insertion loss of 0.6 dB, and the developed device has a maximum phase shift of 770° at the center frequency of 13GHz. The phase shifter can be used for various radar and satellite applications that require phase control, such as beamforming networks and phased array antennas.

  • A hierarchical observer for a non-linear uncertain CSTR model of biochemical processes
    • Mateusz Czyżniewski
    • Rafał Łangowski
    2024 Pełny tekst International Journal of Applied Mathematics and Computer Science

    The problem of estimation of unmeasured state variables and unknown reaction kinetic functions for selected biochemical processes modelled as a continuous stirred tank reactor is addressed in this paper. In particular, a new hierarchical (sequential) state observer is derived to generate stable and robust estimates of the state variables and kinetic functions. The developed hierarchical observer uses an adjusted asymptotic observer and an adopted super-twisting sliding mode observer. The stability of the proposed hierarchical observer is investigated under uncertainty in the system dynamics. The stability analysis of the estimation error dynamics is carried out based on the methodology associated with linear parameter-varying systems and sliding mode regimes. The developed hierarchical observer is implemented in the Matlab/Simulink environment and its performance is validated via simulation. The obtained satisfactory estimation results demonstrate high effectiveness of the devised hierarchical observer.

  • A Low-Profile 3-D Printable Metastructure for Performance Improvement of Aperture Antennas
    • Md Yeakub Ali
    • Ali Lalbakhsh
    • Sławomir Kozieł
    • Łukasz Gołuński
    • Foez Ahmed
    • Mohsen Asadnia
    2024 Pełny tekst Scientific Reports

    In order to increase the radiation performance of aperture-type antennas, this paper demonstrates a low-profile, planar, single-layer, three-dimensional (3-D) printable metastructure. The proposed hybridized metastructure is highly transparent as it is made out of novel hybrid meta-atoms having transmission coefficient magnitudes greater than -0.72 dB and fully complies with the near-field phase transformation principle. The hybridized design approach makes the metastructure planar, low-profile, light in weight, and compatible with additive printing technology. For the proof-of-concept, such metastructure is developed and numerically verified to enhance the radiation performance of a resonant cavity antenna (RCA). With the proposed metastructure, the peak directivity of the RCA is improved by 8.6 dBi (from 11.4 dBi to 20 dBi) at the operating frequency of 12.4 GHz. The aperture efficiency and 3-dB directivity bandwidth of the RCA with the metastructure are 41.46% and 16.5%, respectively. Using readily accessible thermoplastics or polymers and copper with cost-effective fused deposition modeling (FDM) 3-D printing technology, the proposed planar hybridized metastructure can be prototyped commercially.

  • A Low-Profile Metal-backed Dipole Loaded with Closely Coupled Arc-shaped Open Stubs for On-metal Tag Design with Wide Frequency Tuning Capability
    • Fuad Erman
    • Sławomir Kozieł
    • Eng-Hock Lim
    • Leifur Leifsson
    • Effariza Hanafi
    • Muthukannan Murugesh
    2024 IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION

    This research has presented a single-layer metal-backed dipole antenna, which consists of a feedline loaded with two pairs of closely-coupled arc-shaped open stubs, for designing a metal-mountable tag that features tuning capability over a wide range of frequency. Here, the stubs can generate sufficient inductive reactance for bringing down the tag resonant frequency tunable in both the regulated UHF RFID passbands (North American (NA) and Lower European (LEu) standards). Adjusting the stubs’ length can be utilized as a simple and effective tuning mechanism, enabling broadband frequency adjustment in between the two major spectra in a straightforward manner, while maintaining a maximum power transmission coefficient (τ=1). In addition, the proposed antenna structure is easy to construct. The tuning mechanism has enabled the antenna to match well with any commercial RFID chips, and it does not require the use of any external lumped components or shorting elements (vias or stubs). The proposed tag can be easily fabricated using an inexpensive flexible polytetrafluoroethylene (PTFE) substrate, which is broadly adopted by the RFID industry. Stable read performance is achievable, providing freedom of frequency tuning without the need to modify the radiator structure. The volume of the tag is reasonably small:   (28)2  1.5 mm3. It has a measured detection distance is 9.75 m (4 W EIRP) on metal surface in the NA RFID passband while 8.41 m (3.24 W EIRP) in the LEu passband.

  • A Machine Learning Approach for Estimating Overtime Allocation in Software Development Projects
    • Hammed Mojeed
    • Rafał Szłapczyński
    2024 Pełny tekst

    Overtime planning in software projects has traditionally been approached with search-based multi-objective optimization algorithms. However, the explicit solutions produced by these algorithms often lack applicability and acceptance in the software industry due to their disregard for project managers' intuitive knowledge. This study presents a machine learning model that learns the preferred overtime allocation patterns from solutions annotated by project managers and applied to four publicly available software development projects. The model was trained using 1092 instances of annotated solutions gathered from software houses, and the Random Forest Regression (RFR) algorithm was used to estimate the PMs' preference. The evaluation results using MAE, RMSE, and R2 revealed that RFR exhibits excellent predictive power in this domain with minimal error. RFR also outperformed the baseline regression models in all the performance measures. The proposed machine learning approach provides a reliable and effective tool for estimating project managers' preferences for overtime plans.

  • A machine learning approach to classifying New York Heart Association (NYHA) heart failure
    • Krystian Jandy
    • Paweł Weichbroth
    2024 Pełny tekst Scientific Reports

    According to the European Society of Cardiology, globally the number of patients with heart failure nearly doubled from 33.5 million in 1990 to 64.3 million in 2017, and is further projected to increase dramatically in this decade, still remaining a leading cause of morbidity and mortality. One of the most frequently applied heart failure classification systems that physicians use is the New York Heart Association (NYHA) Functional Classification. Each NYHA class describes a patient’s symptoms while performing physical activities, delivering a strong indicator of the heart performance. In each case, a NYHA class is individually determined routinely based on the subjective assessment of the treating physician. However, such diagnosis can suffer from bias, eventually affecting a valid assessment. To tackle this issue, we take advantage of the machine learning approach to develop a decision-tree, along with a set of decision rules, which can serve as additional blinded investigator tool to make unbiased assessment. On a dataset containing 434 observations, the supervised learning approach was initially employed to train a Decision Tree model. In the subsequent phase, ensemble learning techniques were utilized to develop both the Voting Classifier and the Random Forest model. The performance of all models was assessed using 10-fold cross-validation with stratification.The Decision Tree, Random Forest, and Voting Classifier models reported accuracies of 76.28%, 96.77%, and 99.54% respectively. The Voting Classifier led in classifying NYHA I and III with 98.7% and 100% accuracy. Both Random Forest and Voting Classifier flawlessly classified NYHA II at 100%. However, for NYHA IV, Random Forest achieved a perfect score, while the Voting Classifier reported 90%. The Decision Tree showed the least effectiveness among all the models tested. In our opinion, the results seem satisfactory in terms of their supporting role in clinical practice. In particular, the use of a machine learning tool could reduce or even eliminate the bias in the physician’s assessment. In addition, future research should consider testing other variables in different datasets to gain a better understanding of the significant factors affecting heart failure.

  • A magnetic imprinted polymer nano-adsorbent with embedded quantum dots and mesoporous carbon for the microextraction of triazine herbicides
    • Nurhasima Phirisi
    • Justyna Płotka-Wasylka
    • Opas Bunkoed
    2024 JOURNAL OF CHROMATOGRAPHY A

    A magnetic molecularly imprinted polymer (MMIP) adsorbent incorporating amino-functionalized magnetite nanoparticles, nitrogen-doped graphene quantum dots and mesoporous carbon (MIP@MPC@NGQDs@ Fe3O4–NH2) was fabricated to extract triazine herbicides from fruit juice. The embedded magnetite nanoparticles simplified the isolation of the adsorbent from the sample solution. The N-GQDs and MPC enhanced adsorption by affinity binding with triazines. The MIP layer provided highly specific recognition sites for the selective adsorption of three target triazines. The extracted triazines were determined by high-performance liquid chromatography (HPLC) coupled with diode-array detection (DAD). The developed method exhibited linearity from 1.5 to 100.0 μg L 1 with a detection limit of 0.5 μg L 1. Recoveries from spiked fruit juice samples were in the range of 80.1– 108.4 %, with a relative standard deviation of less than 6.0 %. The developed MMIP adsorbent demonstrated good selectivity, high extraction efficiency, ease of fabrication and use, and good stability.

  • A magnetic stir bar sorbent of metal organic frameworks, carbon foam decorated zinc oxide and cryogel to enrich and extract parabens and bisphenols from food samples
    • Sirintorn Jullakan
    • Natnaree Rattanakunsong
    • Justyna Płotka-Wasylka
    • Opas Bunkoed
    2024 JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES

    A porous composite magnetic stir bar adsorbent was fabricated for the extraction and enrichment of parabens and bisphenols from selected beverage samples. The adsorbent comprised a metal organic framework, carbon foam decorated zinc oxide and magnetic nanoparticles embedded in polyvinyl alcohol cryogel. The porous composite stir bar adsorbent could adsorb parabens and bisphenols via hydrogen bonding, π-π and hydrophobic interactions. In the best conditions, linearity was good from 5.0 to 200.0 µg/L for methyl paraben, ethyl paraben and bisphenol A and from 10.0 to 200.0 µg/L for bisphenol B and butyl paraben. Limits of detection ranged from 1.5 to 3.0 µg/L. The developed composite stir bar was successfully applied to extract and determine parabens and bisphenols in fruit juice, beer and milk. Recoveries ranged from 89.5 to 99.5 % with RSDs lower than 6 %. The developed sorbent and new methodology were evaluated in terms of its green character with satisfactory results.

  • A method to synthesise groove cam Geneva mechanisms with increased dwell period
    • Viacheslav Pasika
    • Pavlo Nosko
    • Oleksii Nosko
    • Oleksandr Bashta
    • Volodymyr Heletiy
    • Volodymyr Melnyk
    2024 Pełny tekst PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART C-JOURNAL OF MECHANICAL ENGINEERING SCIENCE

    The present study develops a method to synthesise the groove cam Geneva mechanism with increased dwell period. The main condition of the synthesis is to provide the desired law of motion of the wheel. Additional synthesis conditions are the limitation of the maximum pressure angle and the limitation of the minimum curvature radius of the cam profile. Unlike the conventional Geneva mechanisms, the synthesised groove cam Geneva mechanisms enable motion of the wheel due to an arbitrarily specified law, double locking of the wheel at its dwell-to-motion and motion-to-dwell transitions, absence of soft impacts in the extreme positions. The analysis shows that for the cycloidal law of motion, number of slots in range 3 to 15 and additional dwell coefficient in range 0 to 0.7, the operating time coefficient can be provided in wide range from 0.053 to 0.765. The effectiveness of the method is illustrated by numerical examples.

  • A methodology for ultimate strength assessment of ship hull girder accounting for enhanced corrosion degradation modelling
    • Krzysztof Wołoszyk
    • Floris Goerlandt
    • Jakub Montewka
    2024 MARINE STRUCTURES

    The presented work shows a methodology for the ultimate strength assessment of a ship hull, considering enhanced corrosion modelling. The approach is based on the classical Smith method. However, the recent findings regarding the impact of corrosion degradation on ultimate strength are incorporated. To this end, the stress–strain relationships for particular elements composing ship hull cross-section are modified using a specially developed correction factor. The proposed approach is validated with experimental results of the corroded box girders available in the literature, showing very good agreement. Further, a case study of a VLCC tanker ship is presented, and a comparison between contemporary and enhanced corrosion degradation modelling in terms of resulting ultimate strength is presented. The results indicate that the currently used method may significantly overestimate the hull’s structure capacity, especially considering the long exploitation period. Thus, current approaches lead to a non-conservative assessment of the ship hull girder’s ultimate strength, potentially increasing the risk of failure. It is therefore recommended to further investigate the proposed method, especially in the context of risk-based ship design approaches and holistic maritime transportation risk management.

  • A model for agribusiness supply chain risk management using fuzzy logic. Case study: Grain route from Ukraine to Poland
    • Ievgen Medvediev
    • Dmitriy Muzylyov
    • Jakub Montewka
    2024 Pełny tekst TRANSPORTATION RESEARCH PART E-LOGISTICS AND TRANSPORTATION REVIEW

    In order to establish new logistics routes, it is necessary to address several technical and organizational issues, among others. One of the most important criteria for evaluating the performance of a supply chain is the delivery time, proactive consideration of potential hazards and associated uncertainties that may occur along the route. However, the existing solutions are often passive and reactive, based on statistics, thus not leaving much room for proactive risk mitigation measures. Therefore, there is a need for a foreseeing modern approach to account for the impact of anticipated hazards on delivery time. The aim of this study is to develop a model for determining delivery time considering expected risk factors (RF), based on mathematical tools of fuzzy logic and actual background knowledge elicited from the literature and experts. The paper identifies primary technical and operational hazards that occur during loading and transport and converts them into risk factors. The risk factors are then quantified and fed into a fuzzy model developed with the Matlab Fuzzy Logic Toolbox and assembled in the Simulink environment. The application of the model is demonstrated in three case studies reflecting three potential grain supply chains (SC) from Ukraine to Poland: classical transport by rail grain hoppers (SC1); transport by containers on railway platforms (SC2); transport by bulk grain trucks (SC3). The resulting travel time for the analysed SCs is between 49 and 71 hours for SC1, between 45 and 62 hours for SC2 and between 42 and 62 hours for SC3. In addition, the outliers of the travel time values beyond the 1.5 quantiles were defined according to the uncertainty band. The results of the fuzzy model were compared with the results of the deterministic approach in the concurrent validation and a good agreement was found. This proves the appropriateness of the fuzzy model calculations and the possibility of using alternative SCs in grain delivery. The main benefit of the proposed model is a new universal tool based on a holistic and active approach to risk assessment using fuzzy logic.

  • A multiparameter simulation-driven analysis of ship response when turning concerning a required number of irregular wave realizations
    • Przemysław Krata
    • Mateusz Gil
    • Tomasz Hinz
    • Paweł Kozioł
    2024 OCEAN ENGINEERING

    The growing implementation of Decision Support Systems on modern ships, digital-twin technology, and the introduction of autonomous vessels cause the marine industry to seek accurate modeling of vessel response. Despite the contemporary 6DOF models can be used to predict ship motions in irregular waves, the impact of their stochastic realization is usually neglected and remains under-investigated. Especially in the case of turning, differences arising from the stochastic representation of the waves may result in excessive ship motions or even stability failure during maneuver execution. Therefore, in this study, statistical distributions of maximum amplitudes of roll, pitch, and lateral acceleration calculated in two representative locations on board a passenger vessel were analyzed concerning stochastic wave realization and existing extremes. The research utilized 6DOF simulation data and numerous realizations of the irregular wave with random phases of its components. Furthermore, the required number of wave realizations allowing for capturing the actual ranges of ship response at an assumed confidence level has been determined and analyzed. Ultimately, the results were compared in the safety-critical cases concerning various wave and operational conditions. The outcome of this study may be found useful by all parties involved in developing maritime autonomous systems and modeling ship motions.

  • A multiparameter simulation-driven analysis of ship turning trajectory concerning a required number of irregular wave realizations
    • Mateusz Gil
    • Przemysław Krata
    • Paweł Kozioł
    • Tomasz Hinz
    2024 OCEAN ENGINEERING

    In times of progressive automation of the marine industry, accurate modeling of ship maneuvers is of utmost importance to all parties involved in maritime transportation. Despite the existence of modern collisionavoidance algorithms using 6DOF motion models to predict ship trajectories in waves, the impact of stochastic realization of irregular waves is usually neglected and remains under-investigated. Therefore, herein, this phenomenon and its impact were investigated in the case study of the passenger ship’s turning. To this end, statistical and spatiotemporal distributions of ship positions and corresponding trajectory parameters were analyzed. This was made using massive 6DOF simulation data with particular attention to the observed extremes. Additionally, the minimum number of wave realizations has been determined using different methods in various simulation scenarios and afterward compared concerning parameters’ impact and existing dependencies. The results indicate that for simulated scenarios, the required number of wave realizations should be at least 20, but in rough seas should be greater than 30. These values satisfy an acceptable and operationally reasonable error limit reaching 15% of the ship’s length overall. The obtained results may be of interest to autonomous ship developers, scholars, and marine industry representatives working on intelligent collision-avoidance solutions and ship maneuvering models.

  • A New Approach of Solidification Analysis in Modular Latent Thermal Energy Storage Unit Based on Image Processing
    • Rafał Andrzejczyk
    • Muhammad Saqib
    • Michał Rogowski
    2024 Pełny tekst APPLIED THERMAL ENGINEERING

    The solidification process of RT18HC in a cylindrical shell and tube storage unit has been studied using a new methodology based on image processing. The main idea of the algorithm is to label the region of solidification and use statistical functions to calculate the dimensions of the solidification front over time. Said analysis includes two methods. The first method is to measure the solid fraction changes during solidification. The novelty of this method, as compared to other literature findings, is that pre-processing and calculation process occurs automatically via a calculation algorithm. This method is used to calculate the solid fraction of RT18HC which is reported to be a bit fast at the beginning that 40 % of its volume solidified in 1000 s while the rest of the process is completed in almost 6500 s. The second method is used to measure and calculate the thickness of the solid front by using image processing. This method’s error is calculated to be less than 7% throughout the entire process. The second method also acts as an experimental database of front thickness to use in a novel, simplified, semi-theoretical model proposed to calculate the solid front thickness as a function of time in this paper. It is also worth presenting solution extended by a general definition of thermal resistance for a cylindrical partition. The above study will enable the development of an enhanced and optimized model for complex geometries based on image processing techniques in the future. It will also allow the investigation of both processes i.e. solidification and melting alongside other influencing parameters such as the geometry of the storage unit in future.

  • A new strategy for PET depolymerization: Application of bimetallic MOF-74 as a selective catalyst
    • Mateusz Baluk
    • Patrycja Jutrzenka Trzebiatowska
    • Aleksandra Pieczyńska
    • Damian Makowski
    • Malwina Kroczewska
    • Justyna Łuczak
    • Adriana Zaleska-Medynska
    2024 JOURNAL OF ENVIRONMENTAL MANAGEMENT

    Large-volume production of poly(ethylene terephthalate) (PET), especially in the form of bottles and food packaging containers, causes problems with polymer waste management. Waste PET could be recycled thermally, mechanically or chemically and the last method allows to obtain individual monomers, but most often it is carried out in the presence of homogeneous catalysts, that are difficult to separate and reuse. In view of this, this work reports for the first time, application of bimetallic MOF-74 – as heterogeneous catalyst - for depolymerization of PET with high monomer bishydroxyethyl terephthalate, BHET) recovery. The effect of type and amount of second metal in the MOF-74 (Mg/M) was systematically investigated. The results showed increased activity of MOF-74 (Mg/M) containing Co2+, Zn2+ and Mn2+ as a second metal, while the opposite correlation was observed for Cu2+ and Ni2+. It was found that the highest catalytic activity was demonstrated by the introduction of Mg–Mn into MOF-74 with ratio molar 1:1, which resulted in complete depolymerization of PET and 91.8% BHET yield within 4 h. Furthermore, the obtained catalyst showed good stability in 5 reaction cycles and allowed to achieve high-purity BHET, which was confirmed by HPLC analysis. The as-prepared MOF-74 (Mg/Mn) was easy to separate from the post-reaction mixture, clean and reuse in the next depolymerization reaction.

  • A note on the Morse homology for a class of functionals in Banach spaces involving the 2p-area functional
    • Luca Asselle
    • Maciej Starostka
    2024 NODEA-NONLINEAR DIFFERENTIAL EQUATIONS AND APPLICATIONS

    In this paper we show how to construct Morse homology for an explicit class of functionals involving the 2p-area functional. The natural domain of definition of such functionals is the Banach space W_0^{1,2p}(\Omega), where p > n/2 and \Omega \subet R^n is a bounded domain with sufficiently smooth boundary. As W_0^{1,2p}(\Omega) is not isomorphic to its dual space,critical points of such functionals cannot be non-degenerate in the usual sense, and hence in the construction of Morse homology we only require that the second differential at each critical point be injective. Our result upgrades, in the case p > n/2 , the results in Cingolani and Vannella (Ann Inst H Poincaré Anal Non Linéaire 2:271–292, 2003; Ann Mat Pura Appl 186:155–183, 2007), where critical groups for an analogous class of functionals are computed, and provides in this special case a positive answer to Smale’s suggestion that injectivity of the second differential should be enough for Morse theory

  • A Novel Iterative Decoding for Iterated Codes Using Classical and Convolutional Neural Networks
    • Marek Blok
    • Bartosz Czaplewski
    2024

    Forward error correction is crucial for communication, enabling error rate or required SNR reduction. Longer codes improve correction ratio. Iterated codes offer a solution for constructing long codeswith a simple coder and decoder. However, a basic iterative code decoder cannot fully exploit the code’s potential, as some error patterns within its correction capacity remain uncorrected.We propose two neural network-assisted decoders: one based on a classical neural network, and the second employing a convolutional neural network. Based on conducted research, we proposed an iterative neural network-based decoder. The resulting decoder demonstrated significantly improved overall performance, exceeding that of the classical decoder, proving the efficient application of neural networks in iterative code decoding.

  • A Numerical Model Study on Grasse River Ice Control Structures
    • Tomasz Kolerski
    • Hung Tao Shen
    2024 Pełny tekst CANADIAN JOURNAL OF CIVIL ENGINEERING

    Ice jams in the Grasse River have caused the erosion of capping material designed to prevent the resurfacing of the bed sediment in the PCB-contaminated area. Two in-stream ice-control structures are proposed to avoid the jam-induced erosion of the capping material. These two ice-control options are a pier-type ice-control structure and a reconstruction of a small hydropower dam upstream of the capping site. A numerical model study using the DynaRICE model is conducted to evaluate the effectiveness of the proposed design. Flow and ice conditions corresponding to the 100-year return period of ice jam events obtained from analyzing historical breakup ice jam data are used in the evaluation. The results showed that these ice-control structures could reduce the ice discharge downstream and the size of the ice jam at the capping site to prevent the erosion and scour of the PCB-contaminated bed.

  • A palatal prosthesis from archaeological research in the St Francis of Assisi church in Cracow (Poland)
    • Anna E. Spinek
    • Marta Kurek
    • Krzysztof Demidziuk
    • Marcin Nowak
    • Magdalena Śliwka-Kaszyńska
    • Anna Drążkowska
    2024 Journal of Archaeological Science-Reports

    The hard palate is a septum that not only prevents food from entering between the oral and nasal cavity, but also plays an important role during breathing or speech. The presence of cavities within it negatively affects the comfort of life of people with this type of impairment. Hence, in the literature one can find examples of the use of hard palate prostheses to restore the separation between the nasal and oral cavity. During archaeological research conducted in 2017–18 in the church of St Francis of Assisi in Cracow, the remains of a man with a cleft palate, who died at the age of about 50, were found. His burial is dated to the eighteenth century. Within his mouth, the presence of a palatal prosthesis was noted. This is the first case in Poland of finding an individual with an obturator tailored to its needs. The aim of the work is to present the structure and elemental composition of the found prosthesis and comparisons to the other obturators known from written sources. Macroscopic analysis showed the presence of an elliptical-shaped metal diaphragm and a textile “tampon” entering nasal cavity. The metal part of the prosthesis was made of copper alloy, covered with a layer of silver and gold. The comparison of the analysed obturator with examples from the literature indicates its great similarity to those used in the sixteenth and eighteenth centuries.

  • A Planar-Structured Circularly Polarized Single-Layer MIMO Antenna for Wideband Millimetre-Wave Applications
    • Ubaid Ullah
    • Sławomir Kozieł
    • Anna Pietrenko-Dąbrowska
    • Shahanawaz Kamal
    2024 Pełny tekst Engineering Science and Technology-An International Journal-JESTECH

    In this paper, a simple geometry, planar-structured printed multiple-input-multiple-output (MIMO) antenna utilizing dual circular polarization (CP) is presented. The proposed numerically and experimentally validated design features a fully grounded coplanar waveguide (CPW) and a systematically perturbed feedline radiator. The fringing electric (E) field along the feedline is altered by extruding periodic stubs on each side of the microstrip line extended from a grounded CPW. The different physical size of the stubs on each side, plus a slight offset introduced between the stubs breaks the symmetry of the vector E-fields on both side of the edges. The asymmetric E-field weakens the intensity of the respective magnetic current on the opposite side for a wider spectrum, resulting in a wideband operation. The asymmetric vertical magnetic current along the length of the stubs and the combined current on the horizontal edges yield 90-degree out-of-phase orthogonal field components, radiating circularly polarized waves. The proposed design has the advantage of topological simplicity and ease of polarization sense alteration. Owing to this, the design is implemented in MIMO configuration with each port radiating a different sense of CP. The antenna's simulated and measured -10 dB impedance bandwidth is more than 26.5% ranging from 24.6 GHz to 32.1 GHz frequency. Additionally, the antenna retains an axial ratio (AR) of 3 dB or less from 26 GHz to 31.8 GHz. The peak realized gain (RG) of the antenna is 10.3 dBic with an average value of ~ 9.5 dBic across the bandwidth confirming stable radiation in the broadside direction. At the same time, the envelop correlation coefficient and the diversity gain are about 0.01 and 10 dB, respectively over the operating band.

  • A probabilistic-driven framework for enhanced corrosion estimation of ship structural components
    • Krzysztof Wołoszyk
    • Yordan Garbatov
    2024 Pełny tekst RELIABILITY ENGINEERING & SYSTEM SAFETY

    The work proposes a probabilistic-driven framework for enhanced corrosion estimation of ship structural components using Bayesian inference and limited measurement data. The new approach for modelling measurement uncertainty is proposed based on the results of previous corrosion tests that incorporate the non-uniform character of the corroded surface of structural components. The proposed framework's basic features are outlined, and the detailed algorithm is presented. Further, the proposed framework is validated by comparison with the classical statistical approach and mass measurements, considering previous experimental work results. Notably, the impact of the number of measuring points is investigated, and the accuracy index is proposed to identify the optimum number of measurements. The developed framework has a significant advantage over the classical approach since measuring uncertainty is incorporated. Additionally, the confidence intervals of both mean value corrosion depth and standard deviation could be gathered due to the probabilistic character of the framework. Thus, the presented approach can potentially be used in the structural health monitoring of ship structural components and reliability analysis.

  • A procedure for the identification of effective mechanical parameters of additively manufactured elements using integrated ultrasonic bulk and guided waves
    • Erwin Wojtczak
    • Magdalena Rucka
    • Angela Andrzejewska
    2024 MEASUREMENT

    The subject of the current work was a simple but robust novel two-stage procedure for the non-destructive determination of effective elastic constants using ultrasonic wave propagation. First, ultrasonic bulk wave velocities measured on cubic samples were used to calculate most of the elements of the stiffness matrix. Secondly, the remaining elements were determined using the dispersion curves of elastic guided waves measured on plate samples. Based on the complete stiffness matrix it was possible to calculate the complete set of effective elastic constants. The algorithm was verified for AM elements produced from PLA filament satisfying the conditions of transversely isotropic and orthotropic material models. For the transversely isotropic samples, Young’s moduli (E) varied from 2.6 to 2.9 GPa, shear moduli (G) equalled between 0.9 and 1.2 GPa, whereas Poisson’s ratios (ν) ranged between 0.20 and 0.32. In orthotropic sample the corresponding values were: E = 1.3–2.8 GPa, G = 0.6–1.2 GPa, and ν = 0.07–0.59. The results of the current study have been compared with references from the literature, giving satisfactory agreement.

  • A prototype information system for managing and pricing e-waste
    • Krystian Jandy
    • Paweł Weichbroth
    2024 Pełny tekst

    There is no doubt that innovation drives development in all areas of human activity, including electrical and electronic equipment. However, the production of new equipment has a significant impact on the natural environment and a relatively high consumption of natural resources. To address these issues, the circular economy has been implemented in recent years by promoting and introducing numerous measures to facilitate the recycling of used goods. However, it has been found that there are many obstacles and difficulties currently faced by decision and policy makers. In this paper, we try to fill the research gap by presenting the prototype of an information system (IS) that could help not only these stakeholders, but also other interested parties, to move towards a circular economy through the efficient management of used electrical and electronic equipment (e-waste). In this context, we present the prototype of the system and elaborate on its two main components, namely functionality and user interface. Furthermore, we discuss the future research directions regarding the development of existing and new system features, followed by a comprehensive usability testing.

  • A review of explainable fashion compatibility modeling methods
    • Karolina Selwon
    • Julian Szymański
    2024 ACM COMPUTING SURVEYS

    The paper reviews methods used in the fashion compatibility recommendation domain. We select methods based on reproducibility, explainability, and novelty aspects and then organize them chronologically and thematically. We presented general characteristics of publicly available datasets that are related to the fashion compatibility recommendation task. Finally, we analyzed the representation bias of datasets, fashion-based algorithms’ sustainability, and explainable model assessment. The paper describes practical problem explanations, methodologies, and published datasets that may serve as an inspiration for further research. The proposed structure of the survey organizes knowledge in the fashion recommendation domain and will be beneficial for those who want to learn the topic from scratch, expand their knowledge, or find a new field for research. Furthermore, the information included in this paper could contribute to developing an effective and ethical fashion-based recommendation system.

  • A Review of Recent Advances in Human-Motion Energy Harvesting Nanogenerators, Self-Powering Smart Sensors and Self-Charging Electronics
    • Justyna Gołąbek
    • Michał Strankowski
    2024 Pełny tekst SENSORS

    In recent years, portable and wearable personal electronic devices have rapidly developed with increasing mass production and rising energy consumption, creating an energy crisis. Using batteries and supercapacitors with limited lifespans and environmental hazards drives the need to find new, environmentally friendly, and renewable sources. One idea is to harness the energy of human motion and convert it into electrical energy using energy harvesting devices—piezoelectric nanogenerators (PENGs), triboelectric nanogenerators (TENGs) and hybrids. They are characterized by a wide variety of features, such as lightness, flexibility, low cost, richness of materials, and many more. These devices offer the opportunity to use new technologies such as IoT, AI or HMI and create smart self-powered sensors, actuators, and self-powered implantable/wearable devices. This review focuses on recent examples of PENGs, TENGs and hybrid devices for wearable and implantable self-powered systems. The basic mechanisms of operation, micro/nano-scale material selection and manufacturing processes of selected examples are discussed. Current challenges and the outlook for the future of the nanogenerators are also discussed.

  • A review on analytical models of brushless permanent magnet machines
    • Ahmed Abbas
    • Atif Iqbal
    • Arkadiusz Lewicki
    • Reddy B. Prathap
    • M Mnzool
    2024 Pełny tekst INTERNATIONAL JOURNAL OF NUMERICAL MODELLING-ELECTRONIC NETWORKS DEVICES AND FIELDS

    This study provides an in-depth investigation of the use of analytical and numerical methods in analyzing electrical machines. Although numerical models such as the finite-element method (FEM) can handle complex geometries and saturation effects, they have significant computational burdens, are time-consuming, and are inflexible when it comes to changing machine geometries or input values. Analytical models based on magnetic equivalent circuits (MEC) or solving Maxwell's equations can be faster and more flexible, but less accurate for complex machine structures. The paper focuses on the recent development of analytical models for brushless permanent-magnet (PM) machines that have become increasingly popular in low and medium- power applications. The literature review covers the recent developments in analytical models for PM machines with respect to various machine quantities such as magnetic flux density components, induced voltage, inductances, electromagnetic force/torque, efficiency, or unbalanced magnetic force (UMF). It outlines the advantages and disadvantages of different analytical models such as the zero-dimensional (0-D), one-dimensional (1-D), two-dimensional (2-D), and three-dimensional (3-D) analytical methods, as well as the Maxwell and basic mathematical analysis. Although the MEC models are faster than the numerical model, they are not as accurate for various structures of electrical machines including a great magnetic air gap. They also note that the analytical models based on the Maxwell equations are faster than the numerical ones and have the potential to obtain acceptable accuracy similar to the numerical models in electrical machines. Overall, this literature review provides valuable insights for researchers and engineers in selecting appropriate analytical models for PM machines. It highlights the trade-offs between accuracy and computational efficiency when choosing between numerical and analytical models, and the flexibility of analytical models to address changes in machine geometries or input values. Additionally, this helps researchers save time in determining appropriate references regarding the analytical models of brushless PM machines.

  • A review on carbon storage via mineral carbonation: Bibliometric analysis, research advances, challenge, and perspectives
    • Xiaodan Lin
    • Xingyang Li
    • Hongwen Liu
    • Grzegorz Boczkaj
    • Yijun Cao
    • Chongqing Wang
    2024 SEPARATION AND PURIFICATION TECHNOLOGY

    Mineral carbonation as a way of carbon storage has received a particular attention in the reduction of carbon dioxide (CO2) emission . This work gives a comprehensive description of the research trends and hotspots in the field of mineral carbonation for carbon storage based on bibliometric analysis. A total of 1507 articles were collected from the Web of Science database from 2010 to 2022 and analyzed in details, using a Citepace and VOSviewer software. Keyword cluster analysis indicates that research on mineral carbonation mainly involves natural minerals, industrial wastes, and cement-based materials. Research advances on carbon storage via mineral carbonation are summarized from the aspects of magnesium-based feedstocks and calcium-based feedstocks. Direct aqueous carbonation and indirect carbonation are the most promising methods. Mining tailings and industrial wastes are promising feedstocks for mineral carbonation. The slow kinetics and low carbonation capacity of feedstocks are the main obstacles for industrial application. Finally, challenges and prospects in mineral carbonation are put forward, which is conducive to its rapid and balanced development. This work provides the basis for the future development of cheap, efficient, and green large-scale mineral carbonation processes for carbon storage.

  • A review on fungal-based biopesticides and biofertilizers production
    • Dante Ferreyra-Suarez
    • Octavio García-Depraect
    • Roberto Castro Munoz
    2024 ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY

    The escalating use of inorganic fertilizers and pesticides to boost crop production has led to the depletion of natural resources, contamination of water sources, and environmental crises. In response, the scientific community is exploring eco-friendly alternatives, such as fungal-based biofertilizers and biopesticides, which have proven effectiveness in enhancing plant health and growth while sustainably managing plant diseases and pests. This review article examines the production methodologies of these bioproducts, highlighting their role in sustainable agriculture and advancing our understanding of soil microorganisms. Despite their increasing demand, their global market presence remains limited compared to traditional chemical counterparts. The article addresses: 1) the production of biofertilizers and biopesticides, 2) their contribution to crop productivity, 3) their environmental impact and regulations, and 4) current production technologies. This comprehensive approach aims to promote the transition towards more sustainable agricultural practices.

  • A review on homogeneous and heterogeneous catalytic microalgal lipid extraction and transesterification for biofuel production
    • Vinoth Kumar Ponnumsamy
    • Hussein Al-Hazmi
    • Sutha Shobana
    • Jeyaprakash Dharmaraja
    • Dipak Ashok Jadhav
    • Rajesh Banu J
    • Grzegorz Piechota
    • Bartłomiej Igliński
    • Vinod Kumar
    • Amit Bhatnagar
    • Kyu-Jung Chae
    • Gopalakrishnan Kumar
    2024 Pełny tekst CHINESE JOURNAL OF CATALYSIS

    Extracting lipids from microalgal biomass presents significant potential as a cost-effective approach for clean energy generation. This can be achieved through the chemical conversion of lipids to produce fatty acid methyl esters via transesterification. The extraction mainly involves free fatty acids, phospholipids, and triglycerides, and requires less energy, making it an attractive option for satisfying the growing demand for fossil-derived energies. Several approaches have been explored for sustainable bioenergy production from microalgal species via catalytic, non-catalytic, and enzymatic transesterification. This review discusses recent insights into microalgal lipid extraction via solvent, Soxhlet, Bligh and Dyer’s, supercritical CO2, and ionic liquids solvent methods and lipid conversion by transesterification and homo/heterogeneous acid/base catalyzed, enzymatic, non-catalytic, and mechanically/chemically catalyzed in-situ techniques towards algal bioenergy production. Technical advances in both extraction and conversion are necessary for the commercialization of renewable energy sources.

  • A Review on Metal–Organic Framework as a Promising Catalyst for Biodiesel Production ENERGY & FUELS
    • Giao Van Nguyen
    • Prabhakar Sharma
    • Marek Dzida
    • Van Hung Bui
    • Huu Son Le
    • Ahmed Shabana El-Shafay
    • Huu Cuong Le
    • Duc Trong Nguyen Le
    • Viet Dung Tran
    2024 ENERGY & FUELS

    The rapid depletion of fossil-derived fuels along with rising environmental pollution have motivated academics and manufacturers to pursue more environmentally friendly and sustainable energy options in today’s globe. Biodiesel has developed as an ecologically favorable alternative. However, the mass manufacturing of biodiesel on an industrial scale confronts substantial cost and pricing challenges. To address this issue, high-efficiency catalysts with a large number of active sites are needed, resulting in increased biodiesel output and quality. Metal–organic frameworks (MOFs) have received a lot of interest as a catalyst for converting oils/fats or fatty acids into biodiesel. MOFs are polyporous materials that can alter pore size as well as topological structure. They serve as a versatile foundation for designing active sites to satisfy the unique needs of catalytic reactions and conversion pathways. The purpose of this current work is to shed light on the underlying mechanisms and essential properties of MOF-based catalysts used in biodiesel synthesis. In addition, several methods for connecting active sites inside MOFs are scrutinized, while the properties and usability of MOF-based catalysts for the biodiesel production process are completely compared to other catalysts. More importantly, limits and future research directions about the utilization of MOFs in the biodiesel synthesis route are also critically presented. In general, this review contributes to improved awareness about the potential of MOFs in the biodiesel production sector by investigating the primary mechanism and characteristics of MOF-based catalysts.