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  • Collaborative planning? Not yet seen in Poland. Identifying procedural gaps in the planning system 2003–2023
    • Izabela Mironowicz
    • Michał Marek Ciesielski
    2024 Pełny tekst Bulletin of Geography. Socio-economic Series

    Collaborative planning aims to increase the legitimacy of decision-making in spatial development. In this approach, planning involves debate and engagement in discourse, and participation and interaction between actors are thus at the heart of the planning process. This article examines whether the planning system in Poland as defined for the period 2003–2025 provides a level of participation and deliberation and other qualities that together allow it to be classified as a collaborative model. The legal procedures in the most commonly used planning instruments are therefore analysed in detail to determine whether they provide honest, open, equal and transparent access to the decision-making process to all stakeholders. The analysis reveals numerous deficiencies in the planning procedures that undermine the collaborative nature of spatial planning in Poland. The study summarises the experience of twenty years of spatial planning practice in Poland and provides a useful starting point for assessing the new planning system that has gradually been being implemented since 2023.

  • Colossus from Algebron – Gamification as a Tool to Engage Students in Learning Mathematics
    • Barbara Wikieł
    • Joanna Mytnik
    2024 Scientific Journal of Gdynia Maritime University

    Gamification is a tool that allows for high engagement in performing tasks that have been previously considered difficult or uninteresting. It works exceptionally well in education as it supports students in developing habits of learning and provides them with a visual representation of their progress in acquiring knowledge and skills. Skillful design of gamified academic courses enables the achievement of educational goals set by both the students and the academic teachers. Gamification is helpful for subjects that seem challenging, require a significant amount of effort, or are simply perceived by students as uninteresting or useless. The purpose of the paper is to discuss various aspects of engaging students in the process of learning mathematics by gamification of linear algebra.

  • Combined effect of nitrogen-doped carbon and NiCo2O4 for electrochemical water splitting
    • Laura Kubińska
    • Mariusz Szkoda
    • Malgorzata Skorupska
    • Patrycja Grabowska
    • Marta Gajewska
    • Jerzy P. Lukaszewicz
    • Anna Ilnicka
    2024 Scientific Reports

    Electrocatalytic water splitting for green hydrogen production necessitates effective electrocatalysts. Currently, commercial catalysts are primarily platinum-based. Therefore, finding catalysts with comparable catalytic activity but lower cost is essential. This paper describes spinel-structured catalysts containing nickel cobaltite NiCo2O4, graphene, and additionally doped with heteroatoms. The structure and elemental composition of the obtained materials were analyzed by research methods such as TEM, SEM-EDX, XRD, XPS, and Raman spectroscopy. The electrochemical measurements showed that hybrid materials containing nickel cobaltite NiCo2O4 doped with graphene are highly active catalysts in the hydrogen evolution reaction (Tafel slopes = 91 mV dec−1, overpotential = 468 mV and onset potential = -339 mV), while in the oxygen evolution reaction (Tafel slopes = 51 mV dec−1, overpotential = 1752 mV and onset potential = 370 mV), bare NiCo2O4 without the addition of carbon has a worse activity (for HER: Tafel slopes = 120 mV dec−1, overpotential - does not achieve and onset potential = -404 mV, for OER: Tafel slopes = 54 mV dec−1, overpotential = 1796 mV and onset potential = 410 mV). In terms of stability, comparable results were obtained for each synthesized compound for both the HER and OER reactions.

  • Comment on permeability conditions in finite element simulation of bone fracture healing
    • Agnieszka Sabik
    2024 Pełny tekst COMPUTER METHODS IN BIOMECHANICS AND BIOMEDICAL ENGINEERING

    The most popular model of the bone healing considers the fracture callus as poroelastic medium. As such it requires an assumption of the callus’ external permeability. In this work a systematic study of the influence of the permeability of the callus boundary on the simulated bone healing progress is performed. The results show, that these conditions starts to play significant role with the decrease of the callus size. Typically enforced impermeability inhibits the progress of healing during simulation. A remedy for this effect is imposing drainage conditions at the callus’ boundary.

  • Compact Substrate-Integrated Hexagonal Cavity-Backed Self-Hexaplexing Antenna for Sub-6 GHz Applications
    • Vijay Jayaprakash
    • Chandu Ds
    • Rusan Kumar Barik
    • Sławomir Kozieł
    2024 Pełny tekst IEEE Access

    A self-multiplexing SIW antenna based on hexagonal SIW cavity is proposed. The self-hexaplexing antenna consists of different sizes of resonating elements, which provide the hexaband operations. The antenna resonates at 5 GHz, 5.17 GHz, 5.32 GHz, 5.53 GHz, 5.62 GHz, and 5.72 GHz by employing different slot lengths between the resonating elements. The proposed antenna provides the individual tunable characteristics of the operating frequencies without changing the other resonant frequencies. The self-hexaplexing antenna exhibits a port isolation of > 29 dB between the resonating elements with a low frequency ratio of 1.14. The simulated gains of the antenna are 5.32 dBi, 5.68 dBi, 5.41 dBi, 5.91 dBi, 5.43 dBi and 5.14 dBi at the corresponding operating frequencies. The proposed self-hexaplexer operates in the NR band (n46) that can be suitable for communication system applications.

  • Comparative Analysis of Laboratory-Made and Industrial-Made Sewage Sludge Ash: Implications for Effective Management Strategy Development
    • Bartłomiej Cieślik
    • Oskar Ronda
    • Grządka Elżbieta
    • Jolanta Orzeł
    • Justyna Płotka-Wasylka
    2024 Pełny tekst Toxics

    first_pageDownload PDFsettingsOrder Article Reprints Open AccessArticle Comparative Analysis of Laboratory-Made and Industrial-Made Sewage Sludge Ash: Implications for Effective Management Strategy Development by Bartłomiej Michał Cieślik 1,*ORCID,Oskar Ronda 1ORCID,Elżbieta Grządka 2ORCID,Jolanta Orzeł 2 andJustyna Płotka-Wasylka 1 1 Department of Analytical Chemistry, Faculty of Chemistry, Gdańsk University of Technology, Gabriela Narutowicza 11/12 Str., 80-233 Gdańsk, Poland 2 Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Sklodowska University, M. Curie-Skłodow-9 ska Sq 3, 20-031 Lublin, Poland * Author to whom correspondence should be addressed. Toxics 2024, 12(5), 344; https://doi.org/10.3390/toxics12050344 (registering DOI) Submission received: 13 March 2024 / Revised: 30 April 2024 / Accepted: 7 May 2024 / Published: 8 May 2024 (This article belongs to the Section Metals and Radioactive Substances) Downloadkeyboard_arrow_down Browse Figures Versions Notes Abstract In the pursuit of environmentally and economically sustainable sewage sludge ash (SSA) management methods, researchers often employ laboratory-made SSA (L-SSA) as a substitute for industrial-made SSA (I-SSA) produced in fluidized bed furnaces. To check whether L-SSA is a material that imitates I-SSA well, the fractionation of metals whose presence is a significant problem during SSA management was performed. In addition, the grain distribution, specific surface area, and textural properties of the tested materials were examined. Differences in total Pb and Hg content and mobility of Cu, Ni, Mn, and Zn were observed between I-SSA and L-SSA. Larger particle sizes of L-SSA compared to I-SSA were confirmed, while comparable textural properties and specific surface area of both types of materials were maintained. Based on the results, it was concluded that L-SSA is chemically different compared to I-SSA, and that L-SSA should not be used as a reference in research focused on the design of SSA management methods. Moreover, fractionation of metals was performed in disposed fluidized beds (FBs), which are diverted to non-hazardous waste landfills without prior analysis. It has been proven that studied metals are present in FBs as abundantly as in SSA, while Cu, Mn, and Ni may show higher mobility than in I-SSA.

  • Comparative analysis of mechanical conditions in bone union following first metatarsophalangeal joint arthrodesis with varied locking plate positions: A finite element analysis
    • Agnieszka Sabik
    • Karol Daszkiewicz
    • Wojciech Witkowski
    • Piotr Łuczkiewicz
    2024 Pełny tekst PLOS ONE

    First metatarsophalangeal joint arthrodesis is a typical medical treatment performed in cases of arthritis or joint deformity. The gold standard for this procedure is arthrodesis stabilisation with the dorsally positioned plate. However, according to the authors’ previous studies, medially positioned plate provides greater bending stiffness. It is worth to compare the mechanical conditions for bone formation in the fracture callus for both placements of the locking plate. Two finite element models of the first metatarsophalangeal joint with the dorsally and medially positioned plate were defined in the Abaqus software to simulate differentiation of the fracture callus. A simplified load application, i.e. one single step per each day and the diffusion of the mesenchymal stem cells into the fracture region were assumed in an iterative hardening process. The changes of the mesenchymal stem cells into different phenotypes during the callus stiffening were governed by the octahedral shear strain and interstitial fluid velocity according to Prendergast mechanoregulation theory. Basing on the obtained results the progress of the cartilage and bone tissues formation and their distribution within the callus were compared between two models. The obtained results suggest that after 6 weeks of simulation the healing progress is in general comparable for both plates. However, earlier closing of external callus was observed for the medially positioned plate which had greater vertical bending stiffness. This process enables faster internal callus hardening and promotes symmetrical bridging.

  • Comparative Analysis of Phytochemical Profiles and Selected Biological Activities of Various Morphological Parts of Ligustrum vulgare
    • Szymon Litewski
    • Izabela Koss-Mikołajczyk
    • Barbara Kusznierewicz
    2024 Pełny tekst MOLECULES

    Ligustrum vulgare (LV), widely cultivated in Europe and often used in hedges, has been histori-cally recognized in folk medicine for its potential health benefits. This study focused on exploring the untargeted identification of secondary metabolites in ethanol extracts (70% v/v) from differ-ent morphological parts (young shoots, leaves, flowers and fruits) of LV at various stages of plant development, using ultra-high-performance liquid chromatography with high-resolution mass spectrometry (UHPLC-HRMS). Additionally, the selected biological activities (antioxidant ac-tivity, cyclooxygenase-2 inhibition (COX-2), α-amylase inhibition and cytotoxicity) of the tested extracts were determined. Untargeted metabolomics showed that LV extracts were a rich source of phenylethanoid compounds, flavonoids, iridoids and their derivatives. The flowers of LV had the highest content of oleuropein (33.43 ± 2.48 mg/g d.w.). The lowest antioxidant activity was obtained for ripe and post-seasonal fruits, while in the case of other samples, the activity was at a similar level. All tested extracts showed α-amylase and COX-2 inhibitory activity. In addition, LV extracts showed strong antiproliferative properties in colorectal (HT29) and liver (HepG2) cancer cell lines. The obtained results show the difference in the content of bioactive compounds in various morphological parts of Ligustrum vulgare. These differences may influence the multifac-eted medicinal potential of this plant.

  • Comparative analysis of seismic response reduction in multi-storey buildings equipped with base isolation and passive/active friction-tuned mass dampers
    • Morteza Akbari
    • Mohammad Seifi
    • Tomasz Falborski
    • Robert Jankowski
    2024 ADVANCES IN ENGINEERING SOFTWARE

    This study presents an innovative approach to mitigating seismic responses in multi-storey buildings equipped with a base-isolation (BI) system and passive friction-tuned mass dampers (PFTMDs). The key innovation lies in the combined use of a BI system and a PFTMD system, as well as the activation of this mechanical system by controllers. Additionally, the research design optimizes the parameters of these devices specifically for each earthquake scenario and compares the results to the average of the optimal parameters, which has not been investigated in previous studies. In this study, a 10-storey structure is modeled, featuring a BI system beneath the first floor and a PFTMD system on the roof. The parameters for the BI, PFTMD, BI-PFTMD, and BI-active FTMD (BI-AFTMD) systems are independently optimized using a multi-objective particle swarm optimization (MOPSO) algorithm. To enhance the passive BI-PFTMD system, a proportional-integral-derivative (PID) controller is incorporated into the friction-tuned mass damper system, resulting in the BI-AFTMD hybrid control system that adjusts the final control force transmitted to the structure. The seismic performance of these systems is assessed for the 10-storey building under both far-field and near-field earthquakes. The findings reveal that these control systems significantly decrease average peak displacement, acceleration, and inter-storey drift as compared to an uncontrolled structure, especially when system parameters are optimized for the same earthquake scenario. Using average optimal parameters, the BI-AFTMD system achieves the most substantial reduction in average peak displacement, while the BI system offers the greatest reduction in average peak acceleration and inter-storey drift.

  • Comparative analysis of three‐phase dual active bridge converter with different transformer topology and modern universal control for DC microgrids
    • Serafin Bachman
    • Marek Turzyński
    • Marek Jasiński
    2024 Pełny tekst IET Power Electronics

    The presented work discusses issues related to the use of modern multiphase topologies of Dual Active Bridge (DAB)-type converters. Converters of this type are widely used in most DC microgrid applications. The introduction emphasizes a comparative analysis between single-phase and multi-phase DAB topologies within high-power DC microgrids, delving into their respective advantages, drawbacks, design procedures, and considerations based on the latest knowledge. The publication explores the comparison and selection of viable topologies for deployment in high-power and high-efficiency DC microgrids. The unified method of controlling 1-phase and multi-phase DAB converters was proposed in this design, simplifying the issues of DC microgrid control. All topologies were tested on the same controller concept. The study performs laboratory investigation of DAB 1-phase and 3-phase: Star–Star, and Star–Delta topologies. Attention was paid to maintaining uniform operating conditions of the system, contrary to studies known from the literature, all tests were carried out on the same laboratory stand and the same magnetic components in different configurations. Analytical and laboratory analyses of the Zero Voltage Switching (ZVS) region were performed, accounting for non-linear phenomena. Based on these findings, an assessment of the system’s performance in soft switching was carried out. The pre- sented results were implemented in a simulation model and subsequently validated through tests on a constructed laboratory setup to ensure the proper operation of the system. This work meticulously presents and discusses variations in efficiency, dynamic response, phase current harmonic distribution, phase shift distribution, ZVS switching region, and more among the examined topologies. To ensure a fair comparison, the converter configuration for both simulation and laboratory models utilized identical components across all configurations.

  • Comparative study of bisphenols in e-cigarette liquids: evaluating fabric phase sorptive extraction, ultrasound-assisted membrane extraction, and solid phase extraction techniques
    • Paweł Kubica
    • Dominika Osiecka
    • Abuzar Kabir
    • Natasa Kalogiouri
    • Victoria F. Samanidou
    2024 TALANTA.The International Journal of Pure and Applied Analytical Chemistry

    To address the under-researched risk of bisphenols (BPs) in e-cigarette liquids, comprehensive studies have been conducted to propose optimum sample preparation and analysis methods. To determine twelve BPs in refill liquids for e-cigarettes, three sample preparation methods based on distinct operational and working principles were employed. These included fabric phase sorptive extraction (FPSE), ultrasound-assisted solvent extraction of porous membrane-packed samples (UASE-PMS) and solid phase extraction (SPE) utilizing molecularly imprinted polymers (MIPs) technology. Each extraction method was combined with ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLS-MS/MS). Key parameters of FPSE and UASE-PMS procedures were optimized. This optimization included selection of the FPSE membrane types, durations of extraction and the choice solvents. Comprehensive validation was conducted, demonstrating linearity across a range from 2 to 60 ng/mL for all BPs (BPS, BPA, BPF, BPE, BPB, BPC, BPZ, BPFL, BPBP, BPP, BPG and BPM). Determination coefficients were above 0.9913, signifying linear relationship. The limits of detection (LODs) were established below 0.90 ng/mL, while the limits of quantification (LOQs) were lower than 2.5 ng/mL. Notably, the method based on UASE-PMS was successfully applied to the analysis of refill liquids for e-cigarettes samples. A comparative analysis of the methods highlighted variances in precision, accuracy, and applicable aspects, such as adjustment of parameters, sample preparation time, cost, handling, availability and possible limitations. Three methods have been identified as suitable for analysing BPs in e-cigarette refill liquids, highlighting the necessity to examine their presence in these products.

  • Comparative study of numerical modelling and experimental investigation for vessel-docking operations
    • Xueliang Wen
    • Jianan Zhang
    • Muk Chen Ong
    • Aleksander Kniat
    2024 Pełny tekst MARINE STRUCTURES

    A comparative study between numerical modelling and experimental investigation is performed to validate the developed numerical method for simulating floating dock operations with a vessel on board. Both model-scale and full-scale experimental tests are performed on floating docks with a vessel on board, and the draughts using draught meters, floating positions and bending of the floating dock are measured. The present numerical method is proposed based on a quasi-static assumption during vessel-docking operations. A static analysis model is built to determine the static response of a floating dock under a specific ballast water distribution based on a hydrostatic force model and a Newton-Raphson method. A bending model is proposed to calculate the deflection of the floating dock along the longitudinal direction. Results of the mode-scale tests show that the draught measurements and the floating positions of the dock and vessel predicted using the present numerical method agree well with the corresponding experimental results. It proves the accuracy of the present numerical method for simulating vessel-docking operations. Moreover, a well-designed ballast plan enables successful de-ballasting operations on the model-scale dock, even in the event of one to three pump failures. The comparison of the deflection changes of the floating dock in the field test measurements further proves the accuracy of the present bending model. Therefore, the validated numerical model tested on both model-scale and full-scale docks provides a reliable foundation for creating digital twin of floating docks in shipyards.

  • Comparative study on fracture evolution in steel fibre and bar reinforced concrete beams using acoustic emission and digital image correlation techniques
    • Shahzad Ashraf
    • Magdalena Rucka
    2024 Pełny tekst Case Studies in Construction Materials

    In recent decades, the demand for sustainable construction practices has increased, but raw materials such as reinforcing steel remain scarce. Therefore, steel fibres have emerged as a popular and sustainable choice in the construction industry, offering a cost-effective alternative to traditional steel bar reinforcement for both flatwork and elevated structures. The purpose of this study is therefore to compare the performance of fracture behaviour between steel fibre-reinforced concrete (SFRC) and steel bar-reinforced concrete (SBRC) beams subjected to three-point bending. The fracture process was monitored by using two non-invasive techniques: acoustic emission (AE) and digital image correlation (DIC). The damage level was identified by characterizing the parameter-based AE data such as hit rate, energy release, count, rise time, amplitude, and signal strength. DIC images were employed to visualise the crack propagation in parallel with the AE data. To further understand the fracture characteristics, the integration of 2D source localization of AE events (based on local AE fracture energies) with DIC results was investigated. The parameter-based AE results showed that SBRC beam experienced a high density of AE hits with large peak amplitude events that were accelerated during the pre-peak loading phase. The Ib-value analysis revealed that SBRC beam exhibited a higher degree of fracture magnitude during the primary crack development process than SFRC beam. Following the main cracking stage, SFRC beam demonstrated an improved post-cracking softening behavior and superior ability to arrest crack propagation compared to SBRC beam. The integration of local AE fracture energy and DIC results provided a novel approach for a better understanding of the fracture behaviour in both SFRC and SBRC beams. This study’s findings contribute to more precise monitoring of fracture evolution in SFRC and SBRC beams, ultimately improving the selection process for primary reinforcement in flatwork and elevated structures.

  • Comparison of 2D and 3D culture models in the studies of the biological response induced by unsymmetrical bisacridines in cancer cells
    • Jolanta Kulesza
    2024 Pełny tekst

    Multicellular tumor spheroids are a good tool for testing new anticancer drugs, including those that may target cancer stem cells (CSCs), responsible for cancer progression, metastasis, and recurrence. Therefore, following the initial evaluation of the impact of antitumor unsymmetrical bisacridines (UAs) on lung and colon cancer cells using traditional monolayer cultures, I extended my investigations and applied the spherical model. This approach aimed to uncover the cellular response induced by UAs in these cancer cells, with an additional focus on the CSC-like population. In my research, I showed that UAs affected the viability of the studied cells, as well as their spherogenic potential in 2D and 3D. Furthermore, I proved that the most promising UAs (C-2045 and C-2053) induced apoptosis in HCT116 colon and A549 lung cancer spheroids, to a similar, or even higher extent than in monolayer. Finally, I identified the population of CSC-like cells in 2D and 3D cultures of the studied cell lines by determining the levels of CD166, CD133, CD44, and EpCAM markers and I showed that selected UAs affected the CSC-like population in both cell lines, in A549 more profoundly in 3D than 2D. Thus, I have proven that UAs exhibit high antitumor properties in both 2D and 3D conditions and affect the CSC-like population, which makes them promising candidates for future therapeutic applications.

  • Comparison of 3D Point Cloud Completion Networks for High Altitude Lidar Scans of Buildings
    • Marek Kulawiak
    2024 PHOTOGRAMMETRIC ENGINEERING AND REMOTE SENSING

    High altitude lidar scans allow for rapid acquisition of big spatial data representing entire city blocks. Unfortunately, the raw point clouds acquired by this method are largely incomplete due to object occlusions and restrictions in scanning angles and sensor resolution, which can negatively affect the obtained results. In recent years, many new solutions for 3D point cloud completion have been created and tested on various objects; however, the application of these methods to high-altitude lidar point clouds of buildings has not been properly investigated yet. In the above context, this paper presents the results of applying several state-of-the-art point cloud completion networks to various building exteriors acquired by simulated airborne laser scanning. Moreover, the output point clouds generated from partial data are compared with complete ground-truth point clouds. The performed tests show that the SeedFormer network trained on the ShapeNet-55 data set provides promising shape completion results.

  • Comparison of Deep Neural Network Learning Algorithms for Mars Terrain Image Segmentation
    • Wojciech Wicki
    • Wiktor Burblis
    • Miłosz Tkaczeń
    • Jerzy Demkowicz
    2024 Pełny tekst

    This paper is dedicated to the topic of terrain recognition on Mars using advanced techniques based on the convolutional neural networks (CNN). The work on the project was conducted based on the set of 18K images collected by the Curiosity, Opportunity and Spirit rovers. The data were later processed by the model operating in a Python environment, utilizing Keras and Tensorflow repositories. The model benefits from the pretrained backbones trained for analysis of the RGB images. The project achieves an accuracy of 83.5% when extending the scope of classification to unknown objects and 94.2% when omitting unknown results. The results were compared with related projects of Zooniverse and NASA's Jet Propulsion Laboratory scientific group. From amongst the evaluated configurations, the best results and resource utilization were achieved by applying the UNet architecture with resnext_50 backbone and Adam optimizer.

  • Comparison of Doppler Effect Estimation Methods for MFSK Transmission in Multipath Hydroacoustic Channel
    • Agnieszka Czapiewska
    • Andrzej Łuksza
    • Ryszard Studański
    • Łukasz Wojewódka
    • Andrzej Żak
    2024 Pełny tekst IEEE Access

    Underwater wireless communication remains a challenging topic, particularly for applications such as wreck penetration where multipath and Doppler effects are very intense. These effects are becoming even more difficult to mitigate for fast data transmission systems that utilize wideband signals. Due to the low propagation speed of acoustic wave in the water, there is a significant difference between the Doppler shift for lower and upper frequencies of the utilized spectrum. To address these challenges, this paper describes various methods for determining the Doppler frequency shift for MFSK signals, including cross-correlation, double FFT, pilots, and additional Up-Down chirp signals. The reception quality of the transmitted data in a real environment was used as an evaluation criterion for each method. The tests were carried out in motion within the towing tank for different movement speeds of the transmitter relative to the receiver. The tank’s limited dimensions created conditions for multipath signal propagation. Under very difficult multipath signal propagation conditions, the pilots method was found to be the most effective. It gave over two times lower BER than the well-known Up-Down chirp method.

  • Comparison of experimental results with simulation studies of "digital" hydrostatic transmission
    • Zubair Ahmed Jan
    • Krzysztof Kędzia
    • Paweł Śliwiński
    2024

    The publication presents the results of experimental research on a "digital" hydrostatic transmission conducted at INOE 2000 IHP within the framework of the grant "Method of effective use of the digital hydraulics concept in multi-source hydrostatic drive systems". The primary goal of the research is to compare the effectiveness (efficiency) of using different methods of controlling the pump capacity and the hydraulic motor capacity in multi-source, hydrostatic drive systems and to compare the experimental results with simulation studies obtained in the MATLAB Simulink program.

  • Comparison of heat transfer from single- and double-sided heated horizontal plate under free convection in air with constant heat flux condition
    • Michał Ryms
    • Krzysztof Tesch
    • Witold Lewandowski
    2024 Pełny tekst INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER

    This paper presents the results of an experimental and numerical study of convective heat transfer from a newly designed double-sided heated horizontal plate in air. To ensure equal heat transfer from both surfaces, the plate was equipped with two independently supplied electric heaters and resistance thermometers on each side. Minimizing the plate's thickness reduced lateral heat loss and improved measurement accuracy. The study used the balance method for convective heat transfer analysis, and results were validated through standard numerical calculations for q = const. Additionally, results were compared with experimental literature for intermediate cases, such as a cuboid, where convection occurs from both horizontal and vertical sides. Experimental results for the plate showed a 15.5–18.0% difference from numerical ones and a 24.7–29.3% difference from average extreme cases. These findings, presented as the Nusselt-Rayleigh relationship, were positively verified by numerical calculations, confirming their reliability. This advancement enables separate studies of free convection from the upper and lower parts of horizontal plates.

  • Comparison of methods for diagnosing marine IC engines based on working medium parameters including exhaust gas specific enthalpy
    • Patrycja Puzdrowska
    2024 Pełny tekst Combustion Engines

    Article points out methods currently used to diagnose marine engines in operation. The development of tools and programs for implementing these methods was pointed out. The problem of unsatisfactory measurement susceptibility of marine engines was highlighted. Three methods of parametric diagnosis are presented: measurement of in-cylinder parameters and in exhaust gas duct, numerical simulation due to computer software and calculations based on Wibe function. Unfitness states that were analyzed during tests are presented: reduced injection pressure, obstructed intake air duct and reduced compression ratio. The specific enthalpy of the exhaust gas within one engine cycle was determined as a new diagnostic parameter. As a supplement, thermograms of the engine in various states of inoperability were presented. The obtained results were compared and a series of conclusions derived from them were presented. It was evaluated that numerical simulation is an excellent tool for planning experimental studies. Tests on the engine in operation were found to be the most diagnostically reliable.

  • Comparison of Tire Rolling Resistance Measuring Methods for Different Surfaces
    • Jerzy Ejsmont
    • Grzegorz Ronowski
    • Lisa Ydrefors
    • Wojciech Owczarzak
    • Sławomir Sommer
    • Beata Świeczko-Żurek
    2024 Pełny tekst INTERNATIONAL JOURNAL OF AUTOMOTIVE TECHNOLOGY

    The rolling resistance of car tires is one of the most important parameters characterizing tires today. This resistance has a very significant contribution to the energy consumption of wheeled vehicles. The climate crisis has forced tire and car manufacturers to place great emphasis on the environmental impact of their products. Paradoxically, the development of electric vehicles has led to an even greater importance of rolling resistance, because in electric vehicles, a large part of the influence of grade resistance and inertial resistance has been eliminated due to re-generative braking, which resulted in rolling resistance and air resistance remain as the most important factors. What is more, electric and hybrid vehicles are usually heavier, so the rolling resistance is increased accordingly. To optimize tires for rolling resistance, representative test methods must exist. Unfortunately, the current standards for measuring rolling resistance assume that tests are carried out in conditions that are far from real road conditions. This article compares the results of rolling resistance tests conducted in road conditions with the results of laboratory tests conducted on roadwheel facilities. The overview of results shows that the results of tests conducted in accordance with ISO and SAE standards on steel drums are very poorly correlated with more objective results of road tests. Significant differences occur both in the Coefficients of Rolling Resistance (CRR) and in the tire ranking. Only covering the drums with replicas of road surfaces leads to a significant improvement in the results obtained. For investigations of rolling resistance in non-steady-state conditions, the flat track testing machine (TTF), equipped with asphalt cassettes, is shown to provide measurement data in agreement with the road test data.

  • Completely entangled subspaces of entanglement depth k
    • Maciej Demianowicz
    • Kajetan Vogtt
    • Remigiusz Augusiak
    2024 Pełny tekst PHYSICAL REVIEW A

    We introduce a class of entangled subspaces: completely entangled subspaces of entanglement depth k (k-CESs). These are subspaces of multipartite Hilbert spaces containing only pure states with an entanglement depth of at least k. We present an efficient construction of k-CESs of any achievable dimensionality in any multipartite scenario. Further, we discuss the relation between these subspaces and unextendible product bases (UPBs). In particular, we establish that there is a nontrivial bound on the cardinality of a UPB whose orthocomplement is a k-CES. Further, we discuss the existence of such UPBs for qubit systems.

  • Composite 2D Material-Based Pervaporation Membranes for Liquid Separation: A Review
    • Roberto Castro Munoz
    2024 Pełny tekst MOLECULES

    Today, chemistry and nanotechnology cover molecular separations in liquid and gas states by aiding in the design of new nano-sized materials. In this regard, the synthesis and application of two-dimensional (2D) nanomaterials are current fields of research in which structurally defined 2D materials are being used in membrane separation either in self-standing membranes or composites with polymer phases. For instance, pervaporation (PV), as a highly selective technology for liquid separation, benefits from using 2D materials to selectively transport water or other solvent molecules. Therefore, this review paper offers an interesting update in revising the ongoing progress of PV membranes using 2D materials in several applications, including solvent purification (the removal of water from organic systems), organics removal (the removal of organic molecules diluted in water systems), and desalination (selective water transport from seawater). In general, recent reports from the past 3 years have been discussed and analyzed. Attention has been devoted to the proposed strategies and fabrication of membranes for the inclusion of 2D materials into polymer phases. Finally, the future trends and current research gaps are declared for the scientists in the field.

  • Comprehensive Analysis and Environmental Risk Assessment of Benzotriazoles in Airport Stormwater: A HS-SPME-GC × GC-TOF-MS-Based Procedure as a Tool for Sustainable Airport Runoff Water Management
    • Anna Maria Sulej-Suchomska
    • Kozioł Krystyna
    • Żaneta Polkowska
    2024 Sustainability

    Despite the numerous benefits of intensive air transport development, many activities associated with the operation of airports contribute to environmental pollution. The purpose of this research was the development, optimization, and validation of a headspace–solid-phase microextraction–comprehensive two-dimensional gas chromatography–time of flight–mass spectrometry (HS-SPME-GC × GC-TOF-MS)-based procedure for determining anti-corrosive compounds in airport stormwater. Optimized HS-SPME conditions include: 45 min extraction time, 100 ◦C temperature, 1.0 g salt addition, and 10 min desorption time at 270 ◦C. The developed procedure is sensitive, selective, accurate (recoveries ≥ 80.0%), and precise (the coefficient of variation (CV) ≤ 14.9%), making it a highly suitable tool for extensive airport stormwater quality monitoring. The validated analytical protocol was successfully used to detect pollutants, including 1H-BT, 4-MeBT, 5-MeBT, and 5,6-diMe-1H-BT, in stormwater from various European airports with different flight capacities. Throughout the sampling period at the investigated airports, 1H-benzotriazole was found in the highest concentrations, ranging from below the MQL to 467 mg/L. An ecotoxicological risk assessment revealed that 69% of the sites exhibited high risk levels (Risk Quotient ≥ 1). The developed procedure and carried out environmental risk assessments of benzotriazoles in airport stormwater enable an evidence-based approach to sustainable airport stormwater management.

  • Comprehensive evaluation of physical properties and carbon dioxide capacities of new 2-(butylamino)ethanol-based deep eutectic solvents
    • Bartosz Nowosielski
    • Marzena Jamrógiewicz
    • Iwona Cichowska-Kopczyńska
    • Dorota Warmińska
    2024 PURE AND APPLIED CHEMISTRY

    The aim of this research was to assess the impact of the components of alkanolamine deep eutectic solvents (DESs) on the physical properties of those DESs and their carbon dioxide capacity. To achieve this goal, novel deep eutectic solvents were synthesized by using 2-(butylamino)ethanol (BAE) as the hydrogen bond donor (HBD), along with tetrabutylammonium bromide TBAB), tetrabutylammonium chloride (TBAC), or tetraethy- lammonium chloride (TEAC) as the hydrogen bond acceptors (HBA) at various molar ratios (1:6, 1:8, and 1:10). To confirm the presence of hydrogen bond interactions between the components Fourier Transform Infrared Spectroscopy measurements were conducted. Furthermore, thermal properties, including melting points and thermal stability, of these deep eutectic solvents as well as key physical properties, such as density, viscosity, refractive index, and sound velocity, within the temperature range of 293.15–333.15 K and at a pressure of 0.1 MPa were examined. The effect of the molar ratio of HBA to HBD, the type of anion, and the length of the alkyl chain were studied and analysed in regard to physicochemical properties. In this work, the solubility of carbon dioxide in DESs derived from 2-(butylamino)ethanol, 3-aminopropan-1-ol (AP), and 2-(methylamino)ethanol (MAE) was measured. The highest CO 2 capacity was found for TEAC:MAE 1:10 DES characterized by the shortest alkyl chain length in both HBA and HBD molecules, the highest amine content, and the lowest viscosity. Additionally, the effect of water addition on carbon dioxide solubility was explored. The results showed that the influence of water on CO 2 solubility varies with the type of DES. In general, this work highlighted that DESs can serve as effective media for carbon dioxide capture, and their performance can be tailored by changing the type of hydrogen bond acceptor or donor, their molar ratio and by the addition of water.

  • Comprehensive exploration of technological tensioning effects in welded thin plate girders: an in-depth investigation
    • Hassanein I. Khalaf
    • D. Chodorowska
    • Raheem Al-Sabur
    • Andrzej Kubit
    • Wojciech Macek
    2024 Journal of the Brazilian Society of Mechanical Sciences and Engineering

    Thin-walled plate girders are widely used in structures and construction due to their effectiveness in transferring loads. The permanent deformations of the girder lead to a lack of stability, which necessarily leads to its replacement. Replacing permanently deformed thin-walled load-bearing structures requires large financial outlays. Technological prestressing is one of the most effective methods for studying and treating permanent deflections in girder elements. This study looks at the defection of welded thin-plate S235JR steel girders, examining how technological tensioning effects interact with different loading conditions. Four girders, A2 (welded in bottom caps), A3 (welded in two side caps), and A4 (welded in two side caps and bottom caps), as well as the prestressed B2 girder, which has two welded side caps, were subjected to a bend test. The girders were subjected to a load P (20, 40, 60, 80 and 95) kN. All points were examined during the 95 min of cooling time. For technological compression, the results showed that there is a convergence between the analytical solution and the experimental results, as the most significant deviation achieved in the analysis was 5.21 mm compared to 6 mm experimentally. When the girder is loaded with the force P = 50 N, the maximum deflection achieved at girder A4 is 4 mm, compared with 1mm at girder A2. In prestressed girder B, the deflections that were reached were 2.50 mm, 3.50 mm, and 3.52 mm in the analytical, experimental, and FE numerical models, respectively. The tensions that were reached were 36.96 MPa, 44.28 MPa, and 27.93 MPa.

  • COMPREHENSIVE MONITORING OF CHANGES IN THE GEOMETRIC STRUCTURE OF A HISTORIC BUILDING THE "SALA BHP" IN GDAŃSK
    • Jacek Sztubecki
    • Maciej Niedostatkiewicz
    • Maria Mrówczyńska
    • Tomasz Majewski
    2024 Pełny tekst Civil and Environmental Engineering Reports

    The article presents selected results of the analysis of the comprehensive monitoring of the historical building of the “Sala BHP” in Gdansk. The necessity of monitoring was caused by scratches on its structural and finishing elements that occurred in the previous period. A preliminarily assumed factor that could cause the expansion of existing damages and the possible formation of new ones was the planned implementation of an investment consisting of the erection of multi-storey buildings on adjacent plots. As part of the preventive work, a comprehensive monitoring of the facility was proposed, consisting of geodetic determination of vertical and horizontal displacements of measurement points, measurement of changes in the width of existing cracks, and control of the height of the water table in piezometers located in the area adjacent to the „Sala BHP” building. As part of the technical condition inspection, the collected data was analyzed, and the measurement data was compared. In the course of the studies, no strong correlations between displacements and individual factors were observed, and thus the preliminary thesis on the direct impact of the investment carried out on the neighboring „Sala BHP” building on the formation of scratches was not confirmed. To confirm the conclusion that the current technical condition of the structure is a consequence of the typical operation of a building with a flexible structure, and most importantly, the occurring defects and damages do not threaten the safety of its structure and use, an additional analysis of the uniformity of the obtained displacements occurrence was carried out, using the transformation method for the purpose. The method shows the non-uniformity of the occurrence of the displacements of the control point network. The results of the analysis confirmed the previously formulated conclusions.

  • Computational analysis of power-law fluids for convective heat transfer in permeable enclosures using Darcy effects
    • Maryam Rehman
    • Muhammad Bilal Hafeez
    • Marek Krawczuk
    2024 Pełny tekst JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY

    Natural convection is a complex environmental phenomenon that typically occurs in engineering settings in porous structures. Shear thinning or shear thickening fuids are characteristics of power-law fuids, which are non-Newtonian in nature and fnd wide-ranging uses in various industrial processes. Non-Newtonian fuid fow in porous media is a difcult problem with important consequences for energy systems and heat transfer. In this paper, convective heat transmission in permeable enclosures will be thoroughly examined. The main goal is to comprehend the intricate interaction between the buoyancyinduced convection intensity, the porosity of the casing, and the fuid’s power-law rheology as indicated by the Rayleigh number. The objective is to comprehend the underlying mechanisms and identify the ideal conditions for improving heat transfer processes.The problem’s governing equations for a scientifc investigation are predicated on the concepts of heat transport and fuid dynamics. The fuid fow and thermal behavior are represented using the energy equation, the Boussinesq approximation, and the Navier–Stokes equations. The continuity equation in a porous media represents the conservation of mass. Finite Element Analysis is the numerical method that is suggested for this challenging topic since it enables a comprehensive examination of the situation. The results of the investigation support several important conclusions. The power-law index directly impacts heat transmission patterns. A higher Rayleigh number indicates increased buoyancyinduced convection, which increases the heat transfer rates inside the shell. The porosity of the medium signifcantly afects temperature gradients and fow distribution, and it is most noticeable when permeability is present. The fndings show how, in the context of porous media, these parameters have complicated relationships with one another

  • Computational analysis of substituent effects on proton affinity and gas-phase basicity of TEMPO derivatives and their hydrogen bonding interactions with water molecules
    • Abolfazl Shiroudi
    • Maciej Śmiechowski
    • Jacek Czub
    • Mohamed A. Abdel-Rahman
    2024 Pełny tekst Scientific Reports

    The study investigates the molecular structure of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) and its derivatives in the gas phase using B3LYP and M06-2X functional methods. Intermolecular interactions are analyzed using natural bond orbital (NBO) and atoms in molecules (AIM) techniques. NO2-substituted TEMPO displays high reactivity, less stability, and softer properties. The study reveals that the stability of TEMPO derivatives is mainly influenced by LP(e) → σ∗ electronic delocalization effects, with the highest stabilization observed on the oxygen atom of the nitroxide moiety. This work also considers electron density, atomic charges, and energetic and thermodynamic properties of the studied NO radicals, and their relative stability. The proton affinity and gas-phase basicity of the studied compounds were computed at T = 298 K for O-protonation and N-protonation, respectively. The studied DFT method calculations show that O-protonation is more stable than N-protonation, with an energy difference of 16.64–20.77 kcal/mol (22.80–25.68 kcal/mol) at the B3LYP (M06-2X) method. The AIM analysis reveals that the N–O…H interaction in H2O complexes has the most favorable hydrogen bond energy computed at bond critical points (3, − 1), and the planar configurations of TEMPO derivatives exhibit the highest EHB values. This indicates stronger hydrogen bonding interactions between the N–O group and water molecules.

  • Computational Approach towards Repetitive Design Tasks: The Case Study of Parking Lot Automated Design
    • Jan Cudzik
    • Michał Nessel
    2024 Pełny tekst Sustainability

    The study aims to develop and assess an algorithm for efficiently generating parking spot layouts within predefined area outlines. The algorithm is an attempt to streamline the decisionmaking process by producing different design variants and optimizing the utilization of available space. The algorithm’s primary objective is to streamline decision-making by generating diverse design variants while optimizing the use of available space, with a distinct focus on mitigating environmental impact and fostering ecological well-being. Researchers conduct thorough tests on the algorithm across various outlines, resulting in multiple layout options for each scenario. They analyzed five representative parking locations and compare the algorithm’s results with the existing parking spot layouts. Throughout the evaluation process, they consider quantitative and qualitative data, considering the complexities of communication solutions within each context. The study findings indicate that the algorithm demonstrates comparable or superior performance to existing solutions. Overall, the study highlights the promising potential of algorithmic design approaches in the context of parking lot automated design. Achieving a balance between innovative designs and user-friendly layouts is crucial, and this is achievable by conducting comprehensive analyses that consider various factors. The consistent findings underscore the algorithm’s potential to significantly contribute to sustainable design practices in parking lot layouts, highlighting decreased environmental strain, efficient land use, and creating urban spaces that prioritize ecological benefits. Furthermore, seamlessly integrating algorithmic solutions with existing communication systems is paramount to ensure practical applicability in real-world scenarios. This integration will enable more effective and practical implementation of the algorithm’s outputs in actual parking lot design projects.

  • Computational Bar Size Optimization of Single Layer Dome Structures Considering Axial Stress and Shape Disturbance
    • Ahmed Manguri
    • Najmadeen Saeed
    • Farzin Kazemi
    • Neda Asgarkhani
    • Marcin Szczepański
    • Robert Jankowski
    2024

    A computational method is proposed in this paper to minimize the material usage in the construction of modern spatial frame structures by prestressing a minimal number of members. The computational optimization is conducted in two steps. Firstly, a numerical model of a single-layer dome structure is used to minimize the cross-sectional area through several iterations. Different assumed ratios (r) ranging from 0.95 to 0.75 are multiplied by the designed cross-sectional area, and the optimal actual ratio (R) is determined through multiple steps using MATLAB. The selection of the optimum ratio is based on ensuring structural stability and considering various constraints. Secondly, a computational optimization is performed using the fmincon function in MATLAB, which employs an interior-point optimization algorithm to search for the minimum summation of the function. The algorithm is designed to exclude actuators with negligible actuation, thereby minimizing the number of actuators. Constraints are set on the stress of all members and the nodal displacements to maintain the desirable shape of the optimized structure. The obtained results demonstrate that the cross-sectional area of the numerical dome structure can be reduced by up to 18% by prestressing only nine members. The validity of the results is confirmed by comparing them with those obtained from MATLAB and SAP2000 software.

  • Computational modelling of historic masonry railroad arch bridges
    • Bartosz Sobczyk
    • Łukasz Pyrzowski
    • Mikołaj Miśkiewicz
    2024 COMPUTERS & STRUCTURES

    The problems encountered during the analyzes of structural response of historic masonry railroad arch bridges are described in this paper. The attention is mainly focused on the stiffness of the masonry arches, their strengths and appropriate estimation of railroad load intensity. Issues related to computational modelling of two, existing, almost 130 years old masonry arch railroad bridges are presented in this context. The main properties and results of detailed inspection of the structures are shown. Computational models that were created in the finite element method environment in order to efficiently describe the responses of the bridges under typical loading conditions and estimate their load carrying abilities are presented. The outcomes of several nonlinear static analyses that were conducted for this purpose are discussed. What is more the results of finite element analyses are reviewed against the inspected bridge condition and final conclusions are formulated on that basis. All the analyses allowed to find the possible causes of the deterioration of the bridges condition.

  • Computational Study of Molecular Interactions in ZnCl2(urea)2 Crystals as Precursors for Deep Eutectic Solvents
    • Adrian Malinowski
    • Maciej Śmiechowski
    2024 Crystals

    Deep eutectic solvents (DESs) are now enjoying an increased scientific interest due to their interesting properties and growing range of possible applications. Computational methods are at the forefront of deciphering their structure and dynamics. Type IV DESs, composed of metal chloride and a hydrogen bond donor, are among the less studied systems when it comes to their understanding at a molecular level. An important example of such systems is the zinc chloride–urea DES, already used in chemical synthesis, among others. In this paper, the ZnCl2(urea)2 crystal is studied from the point of view of its structure, infrared spectrum, and intermolecular interactions using periodic density functional theory and non-covalent interactions analysis. The two main structural motifs found in the crystal are a strongly hydrogen-bonded urea dimer assisted by chloride anions and a tetrahedral Zn(II) coordination complex. The crystal is composed of two interlocking parallel planes connected via the zinc cations. The infrared spectrum and bond lengths suggest a partially covalent character of the Zn–Cl bonds. The present analysis has far-reaching implications for the liquid ZnCl2–urea DES, explaining its fluidity, expected microstructure, and low conductivity, among others.

  • Concept of Multifactor Method and Non-Functional Requirements Solution to Increase Resilience through Functional Safety with Cybersecurity Analysis
    • Emilian Piesik
    • Marcin Śliwiński
    • Narayanan Subramanian
    • Janusz Zalewski
    2024 Pełny tekst Eksploatacja i Niezawodność - Maintenance and Reliability

    In the process of designing safety systems, an integrated approach in safety and cybersecurity analysis is necessary. The paper describes a new technique of increasing resilience through integrated analysis of functional safety and cybersecurity. It is a modeling methodology based on the combination of the multifactor method utilizing modified risk graphs, used previously for Safety Integrity Level (SIL) assessment, and the Non-Functional Requirements (NFR) approach. The NFR approach, based on the analysis of graphical representation of conceptual and physical components of the system, contributes a technique to include cybersecurity through the Softgoal Interdependency Graph. The assessment methodology is outlined in detail and applied to a case study involving an industrial control system. The analysis turns out to be effective in both aspects: confirming the findings of the multifactor approach based on modified risk graphs and complementing the traditional analysis to increase resilience in discovering and mitigating security vulnerabilities for SIL assessment by the use of NFR

  • Concept of Wireless Low-Voltage DC Socket for the Residential House Application
    • Viktor Shevchenko
    • Oleksandr Husev
    • Bohdan Pakhaliuk
    • Dmitri Vinnikov
    • Ryszard Strzelecki
    2024 Pełny tekst IEEE Access

    The proposed research is devoted to the comprehensive theoretical and experimental study of the concept of the wireless low power dc socket for residential applications. The main goal of this work is to provide safe dc source for residential customers at power level which is enough in order to supply all typical appliances without power factor correctors. Such types of devices can be already connected to the dc grid and decoupled from ac grid. This paper considers several typical solutions that can be used for realization. The comparative analysis of an LLC converter with a series-parallel compensation circuit is one of the outputs of this paper. Eventually, simulation and experimental verification is given. The main advantages and constraints are discussed in the conclusions.

  • Conceptual design of shore station for an innovative waste collecting vessel
    • Karol Niklas
    • Hanna Pruszko
    • Maciej Reichel
    • J. Jaworska
    • Ewa Marcinkiewicz
    2024 Pełny tekst

    Marine environment protection legislation in the EU requires ships to return waste they generate on voyages to waste-reception facilities in ports. In many harbors there is a need to expand the port infrastructure to enable the operation of Waste Collecting Vessels (WCVs). In addition, these vessels can perform new functions of cleaning port basins and adjacent waterways. A novelty in the presented research on the conceptual design of the shore station is the inclusion of new requirements for an autonomy and modularization of the vessel. The shore station was designed in the form of a floating pontoon, taking into account the various functional requirements addressed in the ship's conceptual design stage. The pontoon consists of modules corresponding to the ship segments moored in them. The conceptual design was intentionally defined in a generalized form to allow for further development and adaptation to local requirements at individual ports.

  • Consideration of Pseudo Strain Energy in Determination of Fatigue Life and Microdamage Healing of Asphalt Mastics
    • Dawid Ryś
    • Cezary Szydłowski
    2024 INTERNATIONAL JOURNAL OF FATIGUE

    Rest periods between cyclic loads can lead to recovery of damage and extension of fatigue life. This phenomenon is referred to as healing. Healing is clearly observed in bituminous materials, such as asphalt mastics, which belong to the components of asphalt mixtures. Due to the nature of road pavement traffic loading, which is characterized by series of intermittent pulses with rest periods, consideration of healing is necessary for accurate fatigue life estimation. Nevertheless, the vast majority of existing methods relies on relationships established using continuous load conditions. The paper presents a new approach to fatigue life determination, based on pseudo strain energy density. Two components of energy released in fatigue test are considered: the energy responsible for damage growth and the energy consumed to counteract the healing effect. Theoretical derivations were verified in experimental tests, which were performed on asphalt mastics using the Dynamic Shear Rheometer (DSR). It was shown that fatigue life increases with the duration of rest periods on a linear-log scale. Moreover, fatigue life and healing abilities of the analysed asphalt mastics were affected by the type of bitumen and filler, as well as the ageing process.

  • Contemporary and Conventional Passive Methods of Intensifying Convective Heat Transfer—A Review
    • Ewa Kozłowska
    • Marek Szkodo
    2024 ENERGIES

    The ever-increasing demand for effective heat dissipation and temperature control in industrial and everyday applications highlights a critical research problem. The need for development is not only in terms of providing thermal comfort to humans but also forms the basis for the efficient operation of machines and equipment. Cooling of industrial machinery and household electronic equipment is a crucial element in any manufacturing process, and the planning and design of appropriate cooling systems continues to be an integral part of the machine design and construction process. Manufacturers aim to maximize performance while minimizing size and weight. This article reviews widely used passive methods to enhance heat transfer, focusing on their effectiveness in improving convective heat transfer. The techniques examined include surface modifications and advanced materials like foamed metals and nanostructured coatings, which influence turbulence and heat transfer coefficients. The key findings demonstrate that surface roughness, perforated fins, and twisted tapes enhance fluid mixing but may increase flow resistance. The review underscores the significance of these passive methods in optimizing cooling system efficiency across various applications. Despite the variety of techniques available, many areas, especially those involving laser beam modifications, remain underexplored, indicating a need for further research in this field.

  • Continuous Biomedical Monitoring in VR Scenarios of Socially Smart and Safe Autonomous Vehicle Interaction
    • Tomasz Kocejko
    • Abdeljalil Abbas-turki
    • Alexandre Brunoud
    2024

    Pedestrians, as vulnerable road users, pose safety challenges for autonomous vehicles (AVs). Their behavior, often unpredictable and subject to change, complicates AV-pedestrian interactions. To address this uncertainty, AV s can enhance safety by communicating their planned trajectories to pedestrians. In this research, we explore the interaction between pedestrians and autonomous vehicles within an industrial environment, focusing on how communicative behavior from the vehicles influences pedestrians' physiology. We investigate the possibility of mea-suring biosignals while participants wear a VR headset and experiment a pedestrian crossing. Our preliminary study reveals subtle variations in delta rhythms when users immersed in VR simulations interact with AV s that either provide or withhold additional information.

  • Continuum contact model for friction between graphene sheets that accounts for surface anisotropy and curvature
    • Aningi Mokhalingam
    • Shakti Gupta
    • Roger Sauer
    2024 PHYSICAL REVIEW B

    Understanding the interaction mechanics between graphene layers and co-axial carbon nanotubes (CNTs) is essential for modeling graphene and CNT-based nanoelectromechanical systems. This work proposes a new continuum contact model to study interlayer interactions between curved graphene sheets. The continuum model is calibrated and validated using molecular dynamics (MD) simulations. These are carried out employing the reactive empirical bond order (REBO)+Lennard-Jones (LJ) potential to model the interactions within a sheet, while the LJ, Kolmogorov-Crespi (KC), and Lebedeva potentials are used to model the interactions between sheets. The continuum contact model is formulated for separation distances greater than 0.29 nm, when sliding contact becomes non-dissipative and can be described by a potential. In this regime, sheet deformations are sufficiently small and do not affect the sheet interactions substantially. This allows to treat the master contact surface as rigid, thus simplifying the contact formulation greatly. The model calibration is conducted systematically for a sequence of different stackings using existing and newly proposed ansatz functions. The calibrated continuum model is then implemented in a curvilinear finite element (FE) shell formulation to investigate the pull-out and twisting interactions between co-axial CNTs. The resisting pull-out forces and torques depend strongly on the chirality of the considered CNTs. The absolute differences between FE and MD results are very small, and can be attributed to model assumptions and loading conditions.

  • Controlling nodal displacement of pantographic structures using matrix condensation and interior-point optimization: A numerical and experimental study
    • Ahmed Manguri
    • Najmadeen Saeed
    • Robert Jankowski
    2024 ENGINEERING STRUCTURES

    This study presents an innovative approach for the precise control of nodal displacements in pantographic structures. The method is founded on the Matrix Condensation of Force Method, seamlessly integrated with an Interior Point Optimization algorithm. This combination offers a unique advantage by allowing users to manipulate displaced nodes within a defined coordination domain. Furthermore, this approach introduces the Interior Point Optimization algorithm as an indispensable tool to eliminate inactive turnbuckles and minimize overall actuation requirements. Traditional control methods typically demand a substantial number of turnbuckles and extensive actuation efforts to attain the desired nodal coordinates. The interconnected nature of node movements, wherein changes in one node affect others, adds complexity to determining the impact of bar length alterations on each node. To address this challenge, precisely control power of the Interior Point Optimization algorithm systematically explores numerous scenarios to identify solutions that minimize both actuation and turnbuckle usage. The current technique's effectiveness is validated through rigorous comparisons with established methods, experimental modeling, and rigorous testing using SAP 2000 software. Notably, the current approach yields remarkable results, requiring a staggering 60% less actuation and reducing the reliance on turnbuckles by up to 40% compared to previous methods. This innovation promises to significantly enhance the efficiency and cost-effectiveness of controlling pantographic structures, marking a substantial advancement in this field.

  • Controlling the europium oxidation state in diopside through flux concentration
    • N. Górecka
    • Tadeusz Lesniewski
    • Sebastian Mahlik
    • Marcin Łapiński
    • Y.-T. Tsai
    • Aleksandra Bielicka-giełdoń
    • Karol Szczodrowski
    2024 DALTON TRANSACTIONS

    This paper explores the connection between the H3BO3 flux concentration and the co-existence of Eu2+ and Eu3+ dopants within CaMgSi2O6 crystals (diopside). The samples were synthesised using a solid-state synthesis method under varying atmospheric conditions, including oxidative (air), neutral (N2), and reductive (H2/N2 mixture) environments. Additionally, some materials underwent chemical modification by partially substituting Si4+ with Al3+ ions acting as charge compensation defects stabilizing Eu3+ luminescence. Depending on the specific synthesis conditions, the materials predominantly displayed either the orange-red luminescence of Eu3+ (under oxidising conditions) or the blue luminescence of Eu2+; however, the comprehensive results confirmed the co-existence of Eu3+/Eu2+ luminescence in both cases. This work shows that varying flux concentrations added during synthesis significantly affect the relative strength of Eu2+ and Eu3+ emissions in a manner dependent on the synthesis atmosphere. The emission of Eu2+ increases with a higher flux concentration in materials synthesised under oxidative and neutral atmospheres independent of the chemical modification. In contrast, for materials obtained under a reductive atmosphere, the changes in the Eu3+ emission intensity depended on the presence or absence of Al3+ ions namely the increase of flux increased the Eu3+ intensity in the case of unmodified materials and decreased in the Al-modified ones. All observed effects were qualitatively explained considering the double role of the flux in the studied system, which besides facilitating the diffusion of chemical species during synthesis acts as a charge compensating agent by creating B′Si centres stabilizing Eu3+ emission.

  • Convenient and efficient N-methylation of secondary amines under solvent-free ball milling conditions
    • Mikołaj Walter
    • Olga Ciupak
    • Karol Biernacki
    • Janusz Rachoń
    • Dariusz Witt
    • Sebastian Demkowicz
    2024 Pełny tekst Scientific Reports

    In the present work, we report the development of a rapid, efcient, and solvent-free procedure for the N-methylation of secondary amines under mechanochemical conditions. After optimization of the milling parameters, a vibrational ball mill was used to synthesize 26 tertiary N-methylated amine derivatives in a short time of 20 min (30 Hz frequency) and high yields ranging from 78 to 95%. An exception was compounds having a hydroxyl group in their structure, for which a decrease in reaction efciency was observed. During our research, we investigated alternate reaction selectivity occurring in compounds able to form ring closure products that are 3,4-dihydro-2H-1,3-benzoxazine derivatives instead of N-methylated products. The liquid-assisted grinding technique has been applied using formalin as a methylating agent and sodium triacetoxyborohydride as a reducing agent in a reductive amination reaction.

  • Corncob-supported calcium oxide nanoparticles from hen eggshells for cadmium (Cd-II) removal from aqueous solutions; Synthesis and characterization
    • Werkne Sorsa Muleta
    • Sultan Mulisa Denboba
    • Abreham Bayu
    2024 Pełny tekst Heliyon

    This study investigated the efficient removal of cadmium ions from aqueous solutions using calcium oxide nanoparticles (CaO NPs) synthesized from waste hen eggshells using a Sol-gel method and supported on corncob bio-adsorbent. The synthesized CaO NPs were characterized using FT-IR, XRD, specific surface area, and TGA. Batch adsorption experiments were conducted to examine the influence of process parameters such as adsorbent dosages, initial Cd (II) concentrations, pH values, and contact times. XRD analysis revealed that the synthesized CaO nanoparticles had a size of 24.34 nm and a specific surface area of 77.4 m2 g. The optimal conditions for achieving the highest percent removal of cadmium (99.108%) were found to be an initial concentration of 55 ppm, pH 7, adsorbent dose of 0.75 g, and contact time of 50 min. The experimental removal efficiency closely matched the predicted value (99.0%), indicating the suitability of the method used in optimizing the removal of Cd (II) ions from aqueous solutions. These findings, corroborated by predicted values, underscore the efficacy of our method in optimizing cadmium removal. Based on these findings, it can be concluded that corncob-supported CaO NPs are optimized for their highest efficiency and hold great promise as a cost-effective and environmentally friendly solution for wastewater treatment with a focus on cadmium removal.

  • Corporate social responsibility and forward default risk under firm and industry heterogeneity
    • Muhammad Mushafiq
    • Błażej Prusak
    • Magdalena Markiewicz
    2024 Pełny tekst Entrepreneurial Business and Economics Review

    Objective: This study aims to evaluate the impact of corporate social responsibility on forward default risk (FDR) under the setting of firm and industry heterogeneity. Research Design & Methods: This study evaluated the impact of corporate social responsibility (CSR) on FDR using the data of 497 companies from 2007-2021 in the S&P 500 index, taking into account firm and industry heterogeneity aspects. This study utilized instrumental variable regression using the generalized method of moments (IV-GMM) estimation technique which is robust for controlling the pertinent issue of endogeneity. Findings: This study found a negative relationship between CSR and FDR in the full sample. From the firm size aspect, this study found that CSR is more effective in mitigating FDR in large-cap firms than in mid-cap firms. Firm age heterogeneity exhibited a distinct behaviour, as young and middle-aged firms had a stronger impact on FDR management in comparison to old firms. Industry heterogeneity showed that industries with higher customer interaction have a higher impact on corporate social responsibility to control FDR. Industries with lower customer interaction have a lower impact on corporate social responsibility and FDR. Implications & Recommendations: We proposed some policy recommendations based on the findings in the context of firm and industry heterogeneity. Especially the management of mid-cap and young corporations should improve the CSR policy to enhance CSR performance which would lead to stabilized protection against FDR. Similarly, consumer-intensive industries should also focus on enhancing CSR initiatives to decrease FDR. Non-consumer-intensive industries should focus on enhancing CSR policy and at the same time pay particular attention to communicating CSR results to end consumers to reduce FDR. Contribution & Value Added: This study is the first to explore CSR’s impact on financial parameters under heterogeneity.

  • Correlations of structural, thermal and electrical properties of sodium doped complex borophosphosilicate glass
    • Zuzanna Milewczyk
    • Sharafat Ali
    • Piotr Okoczuk
    • Jacek Ryl
    • Ryszard Barczyński
    • Natalia Wójcik
    2024 Pełny tekst CERAMICS INTERNATIONAL

    Borophosphosilicate glasses with varying sodium ion concentrations were investigated for their, structural, thermal, and electrical properties. All the obtained glasses were transparent except the glass with the highest sodium content, which exhibited translucency due to inhomogeneities. Increasing sodium content led to reduced boron and silicon content while maintaining a constant B/Si ratio, indicating progressive depolymerization of the glass network. Confocal microscopy, scanning electron microscopy, and atomic force microscopy showed homogeneous and granular structure for samples with lower sodium content, but higher sodium content resulted in visible agglomeration/nanocrystallization. X-ray diffractograms showed amorphous nature for most samples, with samples doped with the highest concentrations of Na2O showing several broad reflections suggesting nanoscale crystallinity. Fourier-transform infrared spectroscopy revealed shifts in dominant bands with increasing sodium content, indicating depolymerization of the borate network. An observed decrease in glass transition temperature and thermal stability with increasing sodium content was attributed to depolymerization and formation of non-bridging oxygens. Impedance spectroscopy revealed two relaxation processes associated with the transport of Na+ ions through two different regions. DC conductivity and activation energy predominantly increased with the sodium ion content at high temperatures.

  • Corrigendum to “An investigation on residual stress and fatigue life assessment of T-shape welded joints” [Eng. Fail. Anal. 141 (2022) 106685]
    • Jeetendra Mourya
    • Greg Wheatley
    • Mohammed Nizam Khan
    • Reza Masoudi Nejad
    • Ricardo Branco
    • Wojciech Macek
    2024 ENGINEERING FAILURE ANALYSIS

    This paper aims to quantitatively evaluate the residual stress and fatigue life of T-type welded joints with a multi-pass weld in different direction. The main research objectives of the experimental test were to test the residual stress by changing direction along with multiple wielding passes and determine the fatigue life of the welded joints. The result shows that compressive residual stress increases in the sample gradually from single-pass weld to double and triple-pass weld. Moreover, the fatigue life of the specimen also gradually improves with an increasing number of welding passes. Performing multi-pass welding in different directions affects the material’s residual stress and fatigue life, which is an essential factor to consider for assuring the strength of the welded joint.

  • Corrigendum to “Experimental analysis on the risk of vortex ventilation and the free surface ventilation of marine propellers”
    • Anna Kozłowska
    2024 APPLIED OCEAN RESEARCH

    The paper presents a discussion of the ventilation inception and air drawing prediction of ships propellers, aiming to predict under what conditions ventilation will happen, and the actual physical mechanism of the ventilation.

  • Corrigendum to “Fatigue life improvement using low transformation temperature weld material with measurement of residual stress” [Int. J. Fatigue 164 (2022) 107137]
    • Jordan Franks
    • Greg Wheatley
    • Pedram Zamani
    • Reza Masoudi Nejad
    • Wojciech Macek
    • Ricardo Branco
    2024 INTERNATIONAL JOURNAL OF FATIGUE

    Welding processes often produce high levels of tensile residual stress. Low transformation temperature (LTT) welding wires utilise phase transformation strains to overcome the thermal contraction of a cooling weld. In this paper, the residual stress within each weld was quantified using the milling/strain gauge method, being the strain change measured as the weldment was milled away. The fatigue tests were conducted under uniaxial loading considering two types of LTT materials. The results show that the crack propagation of all samples was similar in cycles although both LTT materials extended the crack initiation, and, therefore, the overall life of the part. It was found that both LTT materials reduced the residual tensile stresses, increased the residual compressive stresses, leading to increase in fatigue life about 30%.

  • Corrigendum to “The influence of α,ω-diols and SiO2 particles on CO2 absorption and NH3 escaping during carbon dioxide capture in ammonia solutions” [J. CO2 Util. 80 (2024) 102698]
    • Temesgen Amibo
    • Donata Konopacka-Łyskawa
    2024 Pełny tekst Journal of CO2 Utilization

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