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  • DESIGN AND EXECUTION ERRORS AS A CAUSE OF DAMAGE TO ANTI- ELECTROSTATIC FLOORING
    • Sylwia Świątek-Żołyńska
    • Maciej Niedostatkiewicz
    • Władysław Ryżyński
    2024

    Apart from technological lines, industrial floors are a key element in the scope of maintaining the continuity of work of both production plants and logistics centers. The constantly developing industry of industrial flooring includes both classic design and technological flooring solutions, as well as specialist solutions used in facilities where technological processes or storage require system protection against static electricity. The basic design and implementation activity, apart from the use of earthing systems for the elements of the supporting structure of the facility, is the execution of anti-electrostatic floors with parameters and functional features adapted to the function of the facility.

  • Design and Experimental Validation of a Metamaterial-Based Sensor for Microwave Imaging in Breast, Lung, and Brain Cancer Detection
    • Musa Hamza
    • Sławomir Kozieł
    • Anna Pietrenko-Dąbrowska
    2024 Pełny tekst Scientific Reports

    This study proposes an innovative geometry of a microstrip sensor for high-resolution microwave imaging (MWI). The main intended application of the sensor is early detection of breast, lung, and brain cancer. The proposed design consists of a microstrip patch antenna fed by a coplanar waveguide with a metamaterial layer-based lens implemented on the back side, and an artificial magnetic conductor (AMC) realized on as a separate layer. The analysis of the AMC’s permeability and permittivity demonstrate that the structure exhibits negative epsilon (ENG) qualities near the antenna resonance point. In addition, reflectivity, transmittance, and absorption are also studied. The sensor prototype has been manufactures using the FR4 laminate. Excellent electrical and field characteristics of the structure are confirmed through experimental validation. At the resonance frequency of 4.56 GHz, the realized gain reaches 8.5 dBi, with 3.8 dBi gain enhancement contributed by the AMC. The suitability of the presented sensor for detecting brain tumors, lung cancer, and breast cancer has been corroborated through extensive simulation-based experiments performed using the MWI system model, which employs four copies of the proposed sensor, as well as the breast, lung, and brain phantoms. As demonstrated, the directional radiation pattern and enhanced gain of the sensor enable precise tumor size discrimination. The proposed sensor offers competitive performance in comparison the state-of-the-art sensors described in the recent literature, especially with respect to as gain, pattern directivity, and impedance matching, all being critical for MWI.

  • Design and experimental verification of multi-layer waveguide using pin/hole structure
    • Hasan Raza
    • Sławomir Kozieł
    • Leifur Leifsson
    2024 IEEE Antennas and Wireless Propagation Letters

    This study presents a novel technique for minimizing RF leakage in metallic hollow waveguides fabricated using the multilayer split-block method. By integrating a pin/hole wall into the split-block multilayers, a substantial reduction of RF leakage can be achieved while reducing the circuit size and mitigating the performance variations. To validate the proposed approach, a slot antenna fed by single ridge waveguide has been prototyped and experimentally validated. The simulated and measured results demonstrate that the slot antenna is well matched (|S11|  –10 dB) within the frequency range 29 GHz to 34 GHz, whereas its gain is about 8 dBi.

  • Design and Implementation of Multi-Band Reflectarray Metasurface for 5G Millimeter Wave Coverage Enhancement
    • Bilal Malik
    • Shahid Khan
    • Sławomir Kozieł
    2024 Pełny tekst Scientific Reports

    A compact low-profile multi-band millimeter-wave (mm-wave) reflectarray metasurface design is presented for coverage enhancement in 5G and beyond cellular communication. The proposed single-layer metasurface exhibits a stable reflection response under oblique incidence angles of up to 60o at 24 and 38 GHz, and transmission response at 30 GHz, effectively covering the desired 5G mm-wave frequency bands. The proposed reflectarray metasurface is polarization insensitive and performs equally well under TE and TM polarized incident waves due to the symmetric pattern. In addition, the low profile of the proposed metasurface makes it appropriate for conformal applications. In comparison to the state-of-the-art, the proposed reflectarray metasurface unit cell design is not only compact (3.3 × 3.3 mm2) but also offers two reflections and one transmission band based on a single-layer structure. It is easy to reconfigure the proposed metasurface unit cell for any other frequency band by adjusting a few design parameters. To validate the concept of coverage enhancement, a 32 × x32 unit-cell prototype of the proposed reflectarray metasurface is fabricated and measured under different scenarios. The experimental results demonstrate that a promising signal enhancement of 20-25 dB is obtained over the entire 5G mm-wave n258, n259, and n260 frequency bands. The proposed reflectarray metasurface has a high potential for application in mm-wave 5G networks to improve coverage in dead zones or to overcome obstacles that prevent direct communication linkages.

  • Design and Optimization of Metamaterial-based Highly-isolated MIMO Antenna with High Gain and Beam Tilting Ability for 5G Millimeter Wave Applications
    • Bashar Esmail
    • Sławomir Kozieł
    2024 Pełny tekst Scientific Reports

    This paper presents a wideband multiple-input multiple-output (MIMO) antenna with high gain and isolation, as well as beam tilting capability, for 5G millimeter wave (MMW) applications. A single bow-tie antenna fed by a substrate-integrated waveguide (SIW) is proposed to cover the 28 GHz band (26.5–29.5 GHz) with a maximum gain of 6.35 dB. To enhance the gain, H-shaped metamaterial (MM)-based components are incorporated into the antenna substrate. The trust-region (TR) gradient-based search algorithm is employed to optimize the H-shape dimensions and to achieve a maximum gain of 11.2 dB at 29.2 GHz. The MM structure offers zero index refraction at the desired range. Subsequently, the MIMO system is constructed with two vertically arranged radiators. Another MM, a modified square resonator (MSR), is embedded between the two radiators to reduce the mutual coupling and to tilt the antenna main beam. Herein, the TR algorithm is again used to optimize the MSR dimensions, and to enhance the isolation to a maximum of 75 dB at 28.6 GHz. Further, the MSR can tilt the E-plane radiation by ±20˚ with respect to the end-fire direction when alternating between the two ports' excitation. The developed system is validated experimentally with a good matching between the simulated and measured data.

  • Design and Performance Evaluation of the Energy Subsystem of a Hybrid Light andWave Energy Harvester
    • Marcin Drzewiecki
    • Piotr Kołodziejek
    • Jarosław Guziński
    2024 Pełny tekst ENERGIES

    The paper presents the design and performance of an energy subsystem (ES) dedicated to hybrid energy harvesters (HEHs): wave energy converters (WECs) combined with photovoltaic panels (PVPs). The considered ES is intended for compact HEHs powering autonomous end-node devices in distributed IoT networks. The designed ES was tested experimentally and evaluated in relation to the mobile and wireless distributed communication use case. The numerical evaluation was based on the balance of the harvested energy versus the energy consumed in the considered use case. The evaluation results proved that the ES ensured energy surplus over the considered IoT node consumption. It confirmed the proposed solution as convenient to the compact HEHs applied for sustainable IoT devices to power them with renewable energy harvested from light and sea waves. It was found that the proposed ES can provide the energy autonomy of the IoT end node and increase its reliability through a hybrid energy-harvesting approach.

  • DESIGN ERRORS CAUSE AN EMERGENCY OF THE REINFORCED CONCRETE TANK FOR COKE
    • Tomasz Majewski
    • Maciej Niedostatkiewicz
    2024

    The quality of the developed design documentation and the maintenance of the technological regime during construction works have a decisive impact on the subsequent safety of the structure, as well as the safety of use of the building. The paper describes the defects and damages of an open, rectangular reinforced concrete tank for hot process water, which failed during a short period of operation. The article also presents the proposed solution to remove the existing damage to the tank structure.

  • Design of a Cellular Dual-Band Sticker Antenna for Thickness-Independent 3D-Printed Substrates
    • Adrian Bekasiewicz
    • Khadijeh Askaripour
    • Marek Wójcikowski
    • Tuan-Vu Cao
    2024 Pełny tekst

    Additive manufacturing technology provides high flexibility in designing custom enclosures for prototype devices such as nodes of distributed sensor networks. Although integration of components is desired from the perspective of sensor mobility, it might negatively affect the performance of radio-connectivity due to couplings between the antenna and system peripherals, as well as other unaccounted effects of the 3D printed enclosure. In this work, a design of a dual-band cellular antenna is considered. The structure is optimized to work on plastic substrates characterized by thicknesses ranging from 1 mm to 5 mm, respectively. The antenna features a –10 dB bandwidth within frequencies from 0.74 GHz to 1.05 GHz and 1.49 GHz to 1.92 GHz. Owing to a simple topology the structure can be implemented in the form of a copper-based sticker and attached on a 3D printed material (e.g., the enclosure of the device). The radiator has been compared against the state-of-the-art antennas in terms of bandwidth and gain.

  • Design of a Shape-Memory-Alloy-Based Carangiform Robotic Fishtail with Improved Forward Thrust
    • Mithilesh Kumar Koiri
    • Dubey Vineet
    • Kumar Anuj Sharma
    • Daniel Chuchała
    2024 Pełny tekst SENSORS

    Shape memory alloys (SMAs) have become the most common choice for the development of mini- and micro-type soft bio-inspired robots due to their high power-to-weight ratio, ability to be installed and operated in limited space, silent and vibration-free operation, biocompatibility, and corrosion resistance properties. Moreover, SMA spring-type actuators are used for developing different continuum robots, exhibiting high degrees of freedom and flexibility. Spring- or any elasticmaterial- based antagonistic or biasing force is mostly preferred among all other biasing techniques to generate periodic oscillation of SMA actuator-based robotic body parts. In this model-based study, SMA-based spring-type actuators were used to develop a carangiform-type robotic fishtail. Fin size optimization for the maximization of forward thrust was performed for the developed system by varying different parameters, such as caudal fin size, current through actuators, pulse-width modulation signal (PWM), and operating depth. A caudal fin with a mixed fin pattern between the Lunate and Fork “Lunafork” and a fin area of approximately 5000 mm2 was found to be the most effective for the developed system. The maximum forward thrust developed by this fin was recorded as 40 gmf at an operation depth of 12.5 cm in a body of still water.

  • Design of Compact and Wideband Groove Gap Waveguide-Based Directional Couplers
    • Mahdieh Rabbanifard
    • Davood Zarifi
    • Ali Farahbakhsh
    • Michał Mrozowski
    2024 IEEE Access

    This paper proposes a compact cross-shaped groove gap waveguide structure for creating wideband and compact directional couplers with different coupling levels. Groove gap waveguide technology is applied to overcome fabrication challenges of printed and hollow waveguide structures in high frequency bands. The validity of the novel concept is demonstrated through the design and evaluation of several compact broadband directional couplers, featuring 3-, 4.5-, 6-, and 10- dB coupling levels, alongside the fabrication and testing of a compact, wideband 3-dB directional coupler prototype. In addition, an equivalent circuit is proposed to present the behavior of the 3-dB coupler. The comparison of simulation and experimental results for the prototype shows good agreement. The measured transmission coefficients in the output ports are −3±0.5 dB with a phase imbalance of ±2.5∘ over 17.9-24 GHz frequency band. The findings confirm the suitability of the proposed directional coupler structure as a compact and self-packaged solution for high-frequency applications.

  • Designing a high-sensitivity dual-band nano-biosensor based on petahertz MTMs to provide a perfect absorber for early-stage non-melanoma skin cancer diagnostic
    • Musa Hamza
    • Mohammad Islam
    • Sunil Lavadiya
    • Sławomir Kozieł
    • Iftikhar Din Ud
    • Bruno Sanches
    2024 Pełny tekst IEEE SENSORS JOURNAL

    The purpose of this study is development of a novel high-performance low-Petahertz (PHz) biosensor for non-melanoma skin cancer (NMSC) diagnosis. The presented device is designed to work within a microwave imaging regime, which is a promising alternative to conventional diagnostic methods such as visual examination, dermoscopy, and biopsy. The suggested biosensor incorporates a dual-band perfect absorber (operating bands at 0.909 PHz and 1.215 PHz) constructed using aluminum layers separated by a dielectric material. Numerical studies confirm its suitability for NMSC diagnosis, enabling discrimination between healthy and cancerous skin tissues and precise visualization of affected areas. Compared to existing THz devices, the proposed biosensor offers improved sensitivity, a smaller size, and enhanced resolution, attributed partially to the transition to the petahertz band. Moreover, our research highlights the potential of PHz spectroscopy for biomarker detection, advancing non-invasive microwave imaging techniques for NMSC and other skin cancers. The proposed biosensor boasts higher sensitivity, figure of merit (FOM), and quality factor (Q-factor), while its insensitivity to polarization angle ensures superior signal-to-noise ratio and high-resolution imaging, instilling confidence in specialists.

  • Designing a High-sensitivity Microscale Triple-band Biosensor based on Terahertz MTMs to provide a perfect absorber for Non-Melanoma Skin Cancer diagnostic
    • Musa Hamza
    • Mohammad Islam
    • Sławomir Kozieł
    • Muhammad Hamad
    • Iftikhar Din Un
    • Ali Farmani
    • Sunil Lavadiya
    • Mohammad Alibakhshikenari
    2024 Pełny tekst IEEE Photonics Journal

    Non-melanoma skin cancer (NMSC) is among the most prevalent forms of cancer originating in the top layer of the skin, with basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) being its primary categories. While both types are highly treatable, the success of treatment hinges on early diagnosis. Early-stage NMSC detection can be achieved through clinical examination, typically involving visual inspection. An alternative, albeit invasive, method is a skin biopsy. Microwave imaging has gained prominence for non-invasive early detection of various cancers, leveraging distinct dielectric properties of healthy and malignant tissues to discriminate tumors and categorize them as benign or malignant. Recent studies demonstrate the potential of terahertz (THz) spectroscopy for detecting biomarkers by aligning electromagnetic wave frequencies in the low THz range (0.1 to 10 THz) with resonant frequencies of biomolecules, such as proteins. This study proposes an innovative microscale biosensor designed to operate in the THz range for the high-sensitivity and efficient diagnosis of non-melanoma skin cancer. By incorporating meticulously designed metamaterial layers, the sensor's absorption properties can be controlled, a critical aspect for discriminating between normal and NMSC-affected skin. In particular, the interaction between skin and THz waves, influenced by dielectric properties and unique vibrational resonances of molecules within tissue, is crucial for wave propagation and scattering. Extensive numerical studies showcased the suitability of the proposed biosensor for NMSC diagnosis, illustrated through specific case studies. These findings hold the potential to pave the way for further development of non-invasive microwave-imaging-based techniques for detecting NMSC and other types of skin cancer.

  • Designing learning spaces through international and interdisciplinary collaborative design studio: The case of engineer architects and pedagogic students
    • Dorota Wojtowicz-Jankowska
    • Einat Gil
    • Ziemowit Belter
    2024 World Transactions on Engineering and Technology Education

    The study explores the dynamics and outcomes of an international interdisciplinary design studio focusing on innovative learning spaces. Conducted over two years between students of Faculty of Architecture at Gdansk Tech and pedagogic students from Kibbutzim College in Tel Aviv, this design-based study examines the contributions of unique educational program to student learning, the evolution of the design process, collaboration, and the challenges and opportunities that arose from the complex context. Students tackled real-world design challenges and employed digital collaboration tools. The analysis utilized two structured questionnaires to evaluate design process key aspects, with a significant self-reported value of acquired knowledge and skills for both courses and increase in maximum satisfaction ratings in the second year, suggesting a more engaging and rewarding experience for dedicated students.

  • Desirability-based optimization of dual-fuel diesel engine using acetylene as an alternative fuel
    • Van Giao Nguyen
    • Dager Brijesh
    • Ajay Chhillar
    • Sharma Prabhakar
    • M. Sameh Osman
    • Duc. T. Nguyen
    • Jerzy Kowalski
    • Hai Thanh Truong
    • Prem Shanker Yadav
    • Dao Nam Cao
    • Viet Dung Tran
    2024 Pełny tekst Case Studies in Thermal Engineering

    he study examined the dual-fuel engine performance employing acetylene gas as primary fuel and diesel as pilot fuel. The engine's operational parameters were adjusted using the Box-Behnken design, and the results were recorded. The best operating settings were yielded as 81.25 % engine load, 4.48 lpm acetylene gas flow rate and the compression ratio were 18. At this optimized setting the BTE was 27.1 % and the engine emitted 360 ppm of NOx, 56.2 ppm of HC, 104 ppm of CO. The experimental data at optimized setting was compared to the optimized results, and the percentage of errors was within 7 %. Two advanced machine learning methods, LightGBM and Tweedie, were used to predict engine efficiency and emissions. Tweedie-based models had an R2 value of 0.89–1, while LightGBM-based models had an R2 value of 0.38–1. The mean squared error was 0.24–45.04 for Tweedie-based models and 8.5 to 153.89 for LightGBM-based models. On the basis of R2 and MSE, it was observed that Tweedie was superior at making predictions than LightGBM. The study demonstrated the efficient functioning of a dual-fuel engine using acetylene as an alternative fuel for increased performance and lower emissions.

  • Detailed studies of superconducting properties of Y2Pd1.25Ge2.75
    • Hanna Świątek
    • Szymon Królak
    • Leszek Litzbarski
    • Ihor Oshchapovskyy
    • Michał Winiarski
    • Tomasz Klimczuk
    2024 Pełny tekst JOURNAL OF ALLOYS AND COMPOUNDS

    We report a successful synthesis of a high-purity intermetallic germanide Y2Pd1.25Ge2.75, crystallizing in the disordered variant of the AlB2-type structure. A single-phase sample was obtained via arc-melting by deliberately tuning the composition out of the ideal 2:1:3 ratio. Specific heat, electrical resistivity and magnetization measurements show that the compound is a weakly-coupled (λ e-p = 0.58) type-II superconductor with a superconducting transition at Tc = 2.72 K. Additional magnetization measurements conducted under pressure up to 0.55 GPa show suppression of Tc, at a rate of − 0.17 K/GPa. Electronic structure calculations reveal the deep similarity between Y2Pd1.25Ge2.75 and other AlB2-type germanide superconductors, especially the ordered YGa2 phase.

  • Detecting Objects of Various Categories in Optical Remote Sensing Imagery Using Neural Networks
    • Aleksander Madajczak
    • Marcin Ciecholewski
    2024

    The effective detection of objects in remote sensing images is of great research importance, so recent years have seen a significant progress in deep learning techniques in this field. However, despite much valuable research being conducted, many challenges still remain. A lot of research projects focus on detecting objects of a single category (class), while correctly detecting objects of different categories is much harder. The recognition of small and overlapping objects is often very problematic. The highest valued classifiers are universal ones that help accurately detect objects of various categories. This research project compared the efficiency of detecting objects of various categories, such as airports, helicopters, planes, fuel tanks and warships, using various modern neural network architectures in the public remote-sensing dataset for geospatial object detection (RSD-GOD). The results presented in this paper are better than the results of detecting objects of the same categories in the RSD-GOD dataset produced by previous studies.

  • Detection of Alzheimer's disease using Otsu thresholding with tunicate swarm algorithm and deep belief network
    • Praveena Ganesan
    • G. P. Ramesh
    • Przemysław Falkowski-Gilski
    • Bożena Falkowska-Gilska
    2024 Pełny tekst Frontiers in Physiology

    Introduction: Alzheimer’s Disease (AD) is a degenerative brain disorder characterized by cognitive and memory dysfunctions. The early detection of AD is necessary to reduce the mortality rate through slowing down its progression. The prevention and detection of AD is the emerging research topic for many researchers. The structural Magnetic Resonance Imaging (sMRI) is an extensively used imaging technique in detection of AD, because it efficiently reflects the brain variations. Methods: Machine learning and deep learning models are widely applied on sMRI images for AD detection to accelerate the diagnosis process and to assist clinicians for timely treatment. In this article, an effective automated framework is implemented for early detection of AD. At first, the Region of Interest (RoI) is segmented from the acquired sMRI images by employing Otsu thresholding method with Tunicate Swarm Algorithm (TSA). The TSA finds the optimal segmentation threshold value for Otsu thresholding method. Then, the vectors are extracted from the RoI by applying Local Binary Pattern (LBP) and Local Directional Pattern variance (LDPv) descriptors. At last, the extracted vectors are passed to Deep Belief Networks (DBN) for image classification. Results and Discussion: The proposed framework achieves supreme classification accuracy of 99.80% and 99.92% on the Alzheimer’s Disease Neuroimaging Initiative (ADNI) and Australian Imaging, Biomarker and Lifestyle flagship work of ageing (AIBL) datasets, which is higher than the conventional detection models.

  • Detection of circulating tumor cells by means of machine learning using Smart-Seq2 sequencing
    • Krzysztof Pastuszak
    • Michał Sieczczyński
    • Marta Dzięgielewska
    • Rafał Wolniak
    • Agata Drewnowska
    • Marcel Korpal
    • Laura Zembrzuska
    • Anna Supernat
    • Anna J. Żaczek
    2024 Pełny tekst Scientific Reports

    Circulating tumor cells (CTCs) are tumor cells that separate from the solid tumor and enter the bloodstream, which can cause metastasis. Detection and enumeration of CTCs show promising potential as a predictor for prognosis in cancer patients. Furthermore, single-cells sequencing is a technique that provides genetic information from individual cells and allows to classify them precisely and reliably. Sequencing data typically comprises thousands of gene expression reads per cell, which artificial intelligence algorithms can accurately analyze. This work presents machine-learning-based classifiers that differentiate CTCs from peripheral blood mononuclear cells (PBMCs) based on single cell RNA sequencing data. We developed four tree-based models and we trained and tested them on a dataset consisting of Smart-Seq2 sequenced data from primary tumor sections of breast cancer patients and PBMCs and on a public dataset with manually annotated CTC expression profiles from 34 metastatic breast patients, including triple-negative breast cancer. Our best models achieved about 95% balanced accuracy on the CTC test set on per cell basis, correctly detecting 133 out of 138 CTCs and CTC-PBMC clusters. Considering the non-invasive character of the liquid biopsy examination and our accurate results, we can conclude that our work has potential application value.

  • Detection of Closing Crack in Beam Based on Responses Induced by Harmonic Excitation
    • Samrawit Alemayehu Tewelde
    • Marek Krawczuk
    2024 Pełny tekst SENSORS

    The non-linear contact model was chosen to simulate the closed crack in the cantilever beam. The study examines the shape and characteristics of the phase diagram of a cantilever beam with closed cracks. It investigates how various crack properties influence the geometry of the phase diagram and proposes a method for identifying cracks based on their features. The area of each closed curve in the phase diagram is determined using the pixel method. Based on the results, the contact model proves effective in simulating closed cracks and is sensitive to nonlinear closing cracks. The vibration responses of beams with different damage severity and positions exhibit distinct geometric features. The crack parameter is identified by locating the intersection of contour lines on the maps. According to numerical calculations, the phase diagrams for superharmonic resonance seem to be more susceptible to changes in closed cracks with varied damage locations and severity. The wavelet transform is also employed to identify closed cracks using RMS signals, and the results are compared with those obtained from the phase diagram.

  • Detection of People Swimming in Water Reservoirs with the Use of Multimodal Imaging and Machine Learning
    • Jakub Konert
    • Adam Dradrach
    • Jacek Rumiński
    2024

    Every year in many countries, there are fatal unintentional drownings in different water reservoirs like swimming pools, lakes, seas, or oceans. The existing threats of this type require creating a method that could automatically supervise such places to increase the safety of bathers. This work aimed to create methods and prototype solutions for detecting people bathing in water reservoirs using a multimodal imaging system and machine learning. Two types of cameras, RGB and thermal, were integrated and calibrated to form a multimodal imaging system. The system was designed and implemented to acquire real-world data for bathing people in swimming pools. The EfficientDet models were adapted and trained on collected data reaching at least 94% detection accuracy, with the highest result equal to 97.47%. The best accuracy obtained for the thermal data was lower and equal to 94.85%. However, thermal imaging allows observing scenes in low-light conditions or darkness. This could potentially highly improve the effectiveness of rescue missions, decreasing the death rates or improving the health of early rescued people. Thermal imaging could also be more acceptable regarding privacy, as high-frequency biometric features are not as easy to extract from thermal images as from high-resolution RGB images.

  • Determination of safety indicators of the freight wagons by mobile systems
    • Oleksij Fomin
    • P. Prokopenko
    • Ievgen Medvediev
    • L. Degtyareva
    2024 Procedia Structural Integrity

    The organization of the movement of freight trains in Ukraine is an important factor in integrating the country’s railway transport into the European system. A situation that requires a significant renewal of the freight wagon park with modern wagons to meet the freight transportation requirements has arisen. Also, a significant drawback of railway transport in Ukraine is the limitation of the speed of trains, which include freight wagons with a reduced container in an empty state, therefore, at the moment, the issue of improving the methodological and software and instrumental testing tools for evaluating the quality and safety indicators of the movement of such wagons is relevant at the moment. At present, laboratory wagons are used during field tests related to the evaluation of traffic quality indicators, acceptance and admission to operation of railway rolling stock, but the modern state of development of measuring equipment allows in most cases to abandon the use of such wagons during running tests of units rolling stock in favor of mobile hardware and software complexes.

  • Determination of Sodium Ion Diffusion Coefficient in Tin Sulfide@Carbon Anode Material Using GITT and EIS Techniques
    • Andrzej Nowak
    • Paweł Rutecki
    • Mariusz Szkoda
    • Konrad Trzciński
    2024 ENERGIES

    The electroanalytical behavior of SnSx (x = 1, 2) encapsulated into a carbon phase was studied using the galvanostatic intermittent titration technique (GITT) and electrochemical impedance spectroscopy (EIS). These techniques are widely utilized in battery systems to investigate the diffusion of alkali metal cations in anode and cathode materials depending on the concentration of ions in the host material. Here, we report different calculation methods showing how the applied model affects the derived diffusion coefficient. The calculated value of the apparent chemical diffusion coefficient of sodium ions ((Formula presented.)) is in the range of 1 × 10−10 to 1 × 10−15 cm2/s depending on the technique, mathematical protocol, geometry of the electrode material, and applied potential.

  • Determination of the shape of the CFGFT cylindrical column based on laboratory tests
    • Eligiusz Mieloszyk
    • Marcin Abramski
    • Anita Milewska
    2024 Pełny tekst MEASUREMENT

    Analyses were carried out on glass-fibre-reinforced polymer tube columns with reference to laboratory tests. The angles of the glass fibre beams were 20◦, 55◦ and 85◦. The study employed non-classical operational calculus. Various modulated harmonic signal shapes were considered for columns and tubes at buckling. The buckling loads were assessed and compared for different models.

  • Determining an Architectural Character for Durban Residential Streetscapes
    • Louis du Plessis
    2024 Pełny tekst

    In the current global context and in consideration of the Sustainable Development Goals, there is a strong need for urban densification. However, this development is also driven by processes linked to the idea of capitalism and 'economic growth'. Such development often leads to the loss of the 'genius loci' of a place and sometimes even overlooks the fact that the quality of the built environment greatly influences the health and well-being of city dwellers. An important element of the quality of an urban structure is its urban landscape - referred to in this thesis as 'streetscape character'. At present, decision-makers involved in urban development unfortunately perceive little value in the quality aspects of this element and are poorly equipped to maintain or improve the existing streetscape character. The thesis research, using the example of an inner city neighbourhood in Durban, showed that a gap in current research and practical approaches is the recognition of the importance of the architectural details of buildings that define the appearance of the street. The paper shows how key these elements are to the construction of the streetscape and how they allow the context of a place to be described. The work concludes by demonstrating how these elements can support the process of maintaining a distinctive townscape. These findings can be translated into practical aspects and can be used in urban development management decisions to maintain or improve the character of the streetscape, which will ultimately contribute to the creation of a unique 'genius loci'.

  • Development and experimental validation of a novel double-stage yield steel slit damper-buckling restrained brace
    • Farzin Kazemi
    • Neda Asgarkhani
    • Natalia Lasowicz
    • Robert Jankowski
    2024 ENGINEERING STRUCTURES

    This research is focused on the development and experimental validation of a novel double-stage yield steel slit damper-buckling restrained brace (SSD-DYB) system designed for seismic resistance of steel structures. The SSD-DYB integrates the energy dissipation capability of a steel slit damper (SSD) in its initial segment, enhancing performance in the case of lower seismic intensities levels while employing a larger segment for higher load resistance to maintain structural stability. The results of the study show that the proposed SSD-DYB is capable to reduce the weight of similar all-steel buckling restrained braces (BRBs) successfully addressing critical points through stiffeners and top and bottom plates. Additionally, the U-shaped element exhibits resilience during seismic loads, indicating its potential for replacing cores without failure which would be beneficial for seismic retrofitting of buildings. Experimental tests show that varying the number and shape of SSD strips significantly impacts the hysteresis curve's maximum load and dissipated energy (i.e., adding strips increased energy dissipation by 33.48 % for SSD-DYB-1), which can be used to control the proposed device for a specific performance target. Stopper mechanisms within the SSD-DYB regulate load distribution between segments and can be used to control the device and its transmitting capacities. Finally, an optimized SSD-DYB has been proposed with promising performance to be used by researchers for designing new structures or retrofit old ones.

  • Development of a simple biogas analyzer module (BAM) for real-time biogas production monitoring
    • Luciano de Melo
    • Ianny Andrade Cruz
    • Lucas Tadeu Fuess
    • Carlos Eduardo Maynard Santana
    • Ram Naresh Bharagava
    • Sikandar I. Mulla
    • Muhammad Bilal
    • Ganesh Dattatraya Saratale
    • Renan Tavares Figueiredo
    • Luiz Fernando Romanholo Ferreira
    2024 ENVIRONMENTAL TECHNOLOGY

    Anaerobic digestion (AD) relies on the cooperation of specific microbial communities, making it susceptible to process disruptions that could impact biogas production. In this regard, this study presents a technological solution based on the Arduino platform, in the form of a simple online monitoring system that can track the produced biogas profile, named as biogas analyzer module (BAM). The applicability of the BAM focused on monitoring the biogas produced from sugarcane vinasse inoculated with sewage sludge biodigestion processed in mesophilic conditions (38 oC), in a pH range of 6.5–7.5, and following a three-stage operational model: (i) an adaptation (168 h), (ii) complete mixing (168 h), and (iii) bio-stimulation with glycerol (192 h). Then, the lab-made BAM was used to trace the produced biogas profile, which registered a total biogas volume of 8,719.86 cm3 and biomethane concentration of 95.79% (vol.), removing 90.8% (vol) of carbon dioxide (CO2) and 65.2% (vol) of hydrogen sulfide (H2S). In conclusion, the results ensured good accuracy and efficiency to the device created by comparisons with established standards (chromatographic and colorimetric methods), as well as the cost reduction. The developed device would likely be six times cheaper than what is available in the market.

  • Development of a vortex-assisted switchable-hydrophilicity solvent-based liquid phase microextraction for fast and reliable extraction of Zn (II), Fe (II), Pb (II), and Cd (II) from various baby food products
    • Hameed Ul Haq
    • Adil Elik
    • Gursel Isci
    • Merve Ekici
    • Nevcihan Gürsoy
    • Grzegorz Boczkaj
    • Nail Altunay
    2024 FOOD CHEMISTRY

    This manuscript describes the development of a novel liquid phase microextraction (LPME) method for the extraction and determination of Zn (II), Fe (II), Pb (II), and Cd (II) in various infant/baby food and supplements products. The method is based on vortex-assisted extraction combined with a switchable-hydrophilicity solvent (SHS) sample preparation. The SHS, which undergoes reversible phase changes triggered by pH change, enables selective extraction and easy phase separation. A flame atomic absorption spectroscopy was used in the final determination step. Optimization studies revealed, that the optimal pH of the sample solution (after digestion) during analytes extraction is 5.5. A l-proline is added to the sample (375 mM) to ensure the complexation of the target metal cations. After the complexation step, 750 µL of SHS - a N, N-Dimethylcyclohexylamine along with 0.9 mL of 2 M of acetic acid solution is added (hydrophilicity switch-on stage) and mixed manually to obtain a homogeneous solution. In the last stage, 0.45 mL of 10 M NaOH solution (hydrophilicity switch-off stage) is added to the sample solution and a vortex for 100 s is applied to ensure the effective extraction and separation of the complex containing the analytes. At this stage, a cloudy solution is immediately obtained. Finally, the effective phase separation is obtained at the centrifugation step (4000 rpm for 2 mins). The method limit of detection was as 0.03, 0.009, 0.6, and 0.2 ng/L for Zn (II), Fe (II), Cd (II), and Pb (II) respectively with RSD% below 2.0 %. The analysis of certified reference materials and real samples proved the full applicability of the method for routine analysis, contributing to the field of heavy metal analysis and ensuring the safety of baby products. According to the AGREE methodology, this method can be named as green analytical chemistry method with a score of 0.77.

  • Development of advanced machine learning for prognostic analysis of drying parameters for banana slices using indirect solar dryer
    • Nguen Van
    • Prabhu Paramasivam
    • Marek Dzida
    • Sameh M. Osman
    • Duc Trong Nguyen Le
    • Dao Nam Cao
    • Thanh Hai Truong
    • Viet Dung Tran
    2024 Pełny tekst Case Studies in Thermal Engineering

    In this study, eXtreme Gradient Boosting (XGBoost) and Light Gradient Boosting (LightGBM) algorithms were used to model-predict the drying characteristics of banana slices with an indirect solar drier. The relationships between independent variables (temperature, moisture, product type, water flow rate, and mass of product) and dependent variables (energy consumption and size reduction) were established. For energy consumption, XGBoost demonstrates superior performance with an R2 of 0.9957 during training and 0.9971 during testing, alongside minimal MSE of 0.0034 during training and 0.0008 during the testing phase indicating high predictive accuracy and low error rates. Conversely, LGBM shows lower R2 values (0.9061 training, 0.8809 testing) and higher MSE of 0.0747 during training and 0.0337 during testing, reflecting poorer performance. Similarly, for shrinkage prediction, XGBoost outperforms LGBM, evidenced by higher R2 (0.9887 training, 0.9975 testing) and lower MSE (0.2527 training, 0.4878 testing). The comparative statistics showed that XGBoost regularly outperformed LightGBM. The game theory-based Shapley functions revealed that temperature and product types were the most influential features of the energy consumption model. These findings illustrate the practical applicability of the XGBoost and LightGBM models in food drying operations towards optimizing drying conditions, improving product quality, and reducing energy consumption.

  • Development of an emulation platform for synchronous machine power generation system using a nonlinear functional level model
    • Filip Kutt
    • Łukasz Sienkiewicz
    • Szymon Racewicz
    • Michał Michna
    • Roland Ryndzionek
    2024 Pełny tekst Archives of Electrical Engineering

    The article presents the Power Hardware in the Loop (PHIL) approach for an autonomous power system analysis based on the synchronous generator model incorporating magnetic saturation effects. The model was prepared in the MATLAB/Simulink environment and then compiled into the C language for the PHIL platform implementation. The 150 kVA bidirectional DC/AC commercial-grade converter was used to emulate the synchronous generator. It was controlled by the real-time simulation control unit with the prepared synchronous generator model incorporating magnetic saturation effects. The proposed approach was validated on the 125 kVA synchronous generator connected to the active and reactive loads of different values for the steady-state and the transient-state performance studies.

  • Development of an orbital shaker-assisted fatty acid-based switchable solvent microextraction procedure for rapid and green extraction of amoxicillin from complex matrices: Central composite design
    • Adil Elik
    • Yağmur Demirkol
    • Hameed Ul Haq
    • Grzegorz Boczkaj
    • Khan Sanaullah
    • Nail Altunay
    2024 FOOD CHEMISTRY

    In this study, a cheap, fast and simple orbital shaker-assisted fatty acid-based switchable solvent microextraction (OS-FASS-ME) procedure was developed for the extraction of amoxicillin (AMOX) in dairy products, pharmaceutical samples and wastewater prior to its spectrophotometric analysis. Fatty acid-based switchable solvents were investigated for extracting AMOX. The key factors of the OS-FASS-ME procedure were optimized using a central composite design. The linearity of OS-FASS-ME procedure was in the range 5–600 ng mL−1 with a correlation coefficient of 0.991. In five replicate experiments for 20 ng mL−1 of AMOX solution, the recovery and relative standard deviation were 95.8% and 2.2%, respectively. Limits of detection and quantification were found 1.5 ng mL−1 and 5 ng mL−1, respectively. The accuracy, precision, robustness and selectivity of the OS-FASS-ME procedure were investigated in detail under optimum conditions. The OS-FASS-ME procedure was applied to milk, cheese, wastewater, syrups and tablets. A comparison of the results obtained from the reference method and the OS-FASS-ME method showed that the OS-FASS-ME procedure can be successfully applied to complex matrices.

  • Development of novel smartphone-based methods of wine quality assessment
    • Kaja Kalinowska
    2024 Pełny tekst

    The doctoral dissertation concerns the development of novel smartphone-based analytical methods of wine quality evaluation, which would be in line with the stipulations of green and equitable analytical chemistry. This solution is based on the analysis of biogenic amines and selected bioactive compounds. The dissertation is based on four articles containing the results of research which led to the development of smartphone-based approach. It was shown that the comprehensive analytical solution comprised of the experimental setup for smartphone-based analysis and a set of methods for the determination of multiple bioactive compounds can be used for wine quality assessment. The use of experimental setup for smartphone-based analysis facilitates modification and adaptation to particular applications. Furthermore, the portability of the setup and simplification of sample preparation procedures enable not only in-field use but also application in each stage of the manufacturing and distribution process.

  • Development of potent and effective SARS-CoV-2 main protease inhibitors based on maleimide analogs for the potential treatment of COVID-19
    • Karol Biernacki
    • Olga Ciupak
    • Mateusz Daśko
    • Janusz Rachoń
    • Damian Flis
    • Justyna Budka
    • Iwona Inkielewicz-Stępniak
    • Anna Czaja
    • Janusz Rak
    • Sebastian Demkowicz
    2024 Pełny tekst JOURNAL OF ENZYME INHIBITION AND MEDICINAL CHEMISTRY

    In the present work, we report a new series of potent SARS-CoV-2 Main Protease (Mpro) inhibitors based on maleimide derivatives. The inhibitory activities were tested in an enzymatic assay using recombinant Mpro (3CL Protease from coronavirus SARS-CoV-2). Within the set of new Mpro inhibitors, 6e demonstrated the highest activity in the enzymatic assay with an IC50 value of 8.52 ± 0.44 mM. The IC50 value for Nirmatrelvir (PF-07321332, used as a reference) was 0.84 ± 0.37 mM. The cytotoxic properties were determined in the MTT assay using MRC-5 and HEK-293 cell lines. In the course of the investigation, we found that the newly obtained maleimide derivatives are not substantially cytotoxic (IC50 values for most compounds were above 200 mM).

  • Development of thin film SPME sorbents based on deep eutectic solvents and their application for isolation and preconcentration of endocrine-disrupting compounds leaching from diapers to urine
    • Aneta Chabowska
    • Justyna Werner
    • Agnieszka Zgoła-Grześkowiak
    • Julia Płatkiewicz
    • Robert Frankowski
    • Justyna Płotka-Wasylka
    2024 MICROCHEMICAL JOURNAL

    In this study, the thin film solid phase microextraction (TF-SPME) based on a novel sorbent composed of deep eutectic solvent (DES) is proposed. Among several synthesized sorbents the most efficient was DES containing trihexyl(tetradecyl)phosphonium chloride and docosanol mixed with polydimethylsiloxane (PDMS) in a molar ratio 1:3:0.25 to achieve a more stable structure. The proposed sorbent was applied on a fiberglass mesh and used as a TF-SPME sorbent for the determination of fifteen endocrine-disrupting compounds (EDCs): methylparaben (MeP), ethylparaben (EtP), propylparaben (PrP), butylparaben (BuP), benzylparaben (BzP), bisphenol A (BPA), bisphenol S (BPS), bisphenol F (BPF), bisphenol AF (BPAF), bisphenol E (BPE), bisphenol B (BPB), triclosan (TCS), triclocarban (TCC), butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) leaching from diapers to synthetic urine. A central composite design methodology was used to optimize extraction from urine and four factors were tested, such as mass of DES/PDMS, extraction time, desorption time, and volume of triethylamine (additive to the desorbing solvent). The developed methodology was characterized by good metrological parameters (limit of detection (LOD): 0.01–1.15 ng mL 1, precision: 2.5–10.3 %). The method was linear in the range of 0.1 ng mL 1 to 100 ng mL 1 with a satisfactory coefficient of determination. After preconcentration by TF-SPME, EDCs were determined by LC-MS/MS. The main EDCs found in diapers were BPA, BPS, MeP, EtP, and PrP.

  • Diagnostics of the Peripheral Artery Disease with use of Glucose Sensor - A Proof of Concept
    • Ignacy Rogoń
    • Jakub Brzeziński
    • Adam Bujnowski
    • Mariusz Kaczmarek
    • Jerzy Wtorek
    2024

    It is estimated that 13% of population over 50 years old suffer from symptomatic or asymptomatic peripheral artery disease (PAD). Ankle-brachial index (ABI) is viewed as a useful parameter in diagnostics of peripheral arterial disease, however screening tests with usage of this method are not advised. Hypoxia causes increase in lactate values and decrease in blood glucose. We hypothesize that the deficit in blood supply to the muscles of the lower limbs will manifest itself in a lower blood glucose concentration, e.g. in the toe measurement compared to the reference measurement taken in the part of the body where the blood supply is normal or slightly worse. We proposed simple method for determining the foot-toe glucose index (FTGI) based on automatic measurement of glucose concentration in a blood sample. Obtained results suggest that proposed method is more sensitive than cuff/ultrasound doppler method.

  • Diagnostyka off-line stanu izolacji uzwojeń silników 6 kV z wykorzystaniem obrazowania akustycznego wyładowań niezupełnych
    • Marek Adamowicz
    • Marcin Gulczyński
    • Marek Olesz
    2024 Pełny tekst Przegląd Elektrotechniczny

    W zakładach przemysłowych, w których kluczowe procesy produkcyjne są realizowane z wykorzystaniem silników średniego napięcia, dla których diagnostyka izolacji uzwojeń ma istotne znaczenie. W tym celu wykonuje się ocenę porównawczą wyników pomiarów wyładowań niezupełnych (WNZ) wykonywanych dla jednostek tego samego typu, a jej skuteczność w znacznej mierze wynika z wieloletniego doświadczenia diagnosty. Dla opracowania wyników WNZ stosuje się metodę fazowo-rozdzielczą PRPD, która wyznacza określone parametry WNZ w funkcji fazy napięcia przemiennego. Dysponując określonymi wzorcami WNZ można określić rodzaj wady izolacji silnika, bez możliwości lokalizacji jej występowania. W referacie omówiono nowe możliwości wspomagania diagnostyki off-line z wykorzystaniem kamery akustycznej, która analizuje widmo akustyczne WNZ i lokalizuje miejsce ich występowania na optycznym obrazie badanego obiektu. Kamera akustyczna wykorzystuje szeroką gamę mikrofonów szerokopasmowych i wizualizuje sygnał akustyczny w wybranych zakresach częstotliwości.

  • Diamond-Based Supercapacitors with Ultrahigh Cyclic Stability Through Dual-Phase MnO2-Graphitic Transformation Induced by High-Dose Mn-Ion Implantation
    • Sujit Deshmukh
    • Srinivasu Kunuku
    • Paweł Jakóbczyk
    • Adrian Olejnik
    • Chien-Hsu Chen
    • Huan Niu
    • Bing Yang
    • Nianjun Yang
    • Robert Bogdanowicz
    2024 Pełny tekst ADVANCED FUNCTIONAL MATERIALS

    While occasionally being able to charge and dischargemore quickly than batteries, carbon-based electrochemical supercapacitors(SCs) are nevertheless limited by their simplicity of processing, adjustableporosity, and lack of electrocatalytic active sites for a range of redox reactions.Even SCs based on the most stable form of carbon (sp3carbon/diamond)have a poor energy density and inadequate capacitance retention during longcharge/discharge cycles, limiting their practical applications. To constructa SC with improved cycling stability/energy density Mn-ion implanted(high-dose; 1015–1017ions cm−2) boron doped diamond (Mn-BDD) films havebeen prepared. Mn ion implantation and post-annealing process results in anin situ graphitization (sp2phase) and growth of MnO2phase with roundishgranular grains on the BDD film, which is favorable for ion transport. The dualadvantage of bothsp2(graphitic phase) andsp3(diamond phase) carbonswith an additional pseudocapacitor (MnO2) component provides a unique andcritical function in achieving high-energy SC performance. The capacitance ofMn-BDD electrode in a redox active aqueous electrolyte (0.05 M Fe(CN)63-/4−+1MNa2SO4)isashighas51mFcm−2at 10 mV s−1with exceptionalcyclic stability (≈100% capacitance even after 10 000 charge/dischargecycles) placing it among the best-performing SCs. Furthermore, the ultrahighcapacitance retention (≈80% retention after 88 000 charge/discharge cycles)in a gel electrolyte containing a two-electrode configuration shows a promisingprospect for high-rate electrochemical capacitive energy storage applications.

  • Diffusion equations with spatially dependent coefficients and fractal Cauer-type networks
    • Jacky Cresson
    • Anna Szafrańska
    2024 Fractional Calculus and Applied Analysis

    In this article, we formulate and solve the representation problem for diffusion equations: giving a discretization of the Laplace transform of a diffusion equation under a space discretization over a space scale determined by an increment h > 0, can we construct a continuous in h family of Cauer ladder networks whose constitutive equations match for all h > 0 the discretization. It is proved that for a finite differences discretization over a uniform geometric space scale, the representation problem over fractal Cauer networks is possible if and only if the coefficients of the diffusion are exponential functions in the space variable. Such diffusion equations admit a (Laplace) transfer function with a fractional behavior whose exponent is explicit. This allows us to justify previous works made by Sabatier and co-workers in [15,16] and Oustaloup and co-workers [14].

  • Direct reduction of pellets through hydrogen: Experimental and model behaviour
    • Pasquale Cavaliere
    • Angelo Perrone
    • Leandro Dijon
    • Aleksandra Laska
    • Damian Koszelow
    2024 Pełny tekst INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

    This paper presents the hydrogen reduction behaviour of industrial pellets designed for the efficient hydrogen based direct reduction. The pellets were provided with very low non ferrous oxides percentage (0.52 of basicity index) and with the absence on TiO2 oxides. The pellets measured diameters in the range 1.14–1.72 cm and were characterized in terms of porosity, pores size, tortuosity and compression strength. The pellets were reduced in hydrogen atmosphere in a laboratory shaft furnace in the temperature ranges of 600–1200 ◦C at the pressures of 1 and 5 bar. The pellets’ reduction behaviour was analysed in terms of time to reduction, rate of reduction and kinetics constant. All the obtained results were analysed through the employment of a commercial multiobjective optimization tool (modeFrontier) in order to precisely define the effect of each single parameter on the pellets’ reduction. It was also defined the effect of the ongoing reduction rate of the final metallization of the starting iron oxides.

  • Discrete element method modelling of elastic wave propagation in a meso-scale model of concrete
    • Magdalena Knak
    • Michał Nitka
    • Magdalena Rucka
    2024 Pełny tekst ULTRASONICS

    This paper deals with the accurate modelling of ultrasonic wave propagation in concrete at the mesoscopic level. This was achieved through the development of a discrete element method (DEM) model capable of simulating elastic wave signals comparable to those measured experimentally. The main objective of the work was to propose a novel methodology for constructing a meso-scale model of concrete dedicated to the analysis of elastic wave propagation. All the material parameters necessary to prepare a numerical DEM model of concrete at the mesoscopic level were explored and explained. Calibration of the mechanical parameters of the DEM model to match the experimental values involved linking the local, micro-parameters between particles with the global response of the whole sample. The developed numerical model was further used to simulate the propagation of elastic waves in a cubic concrete sample, in the frequency range of 100–500 kHz. The results of the DEM calculations showed good agreement with the experimental ultrasonic signals.

  • Dispersive Micro‐Solid Phase Extraction of Selected Metals in Water and Food Samples Followed by ICP‐OES Analysis: Method Development, Analysis of Real Samples and Greenness Evaluation
    • Muhammad Sajid
    • Muhamed Kabeer
    • Mazen Khaled Nazal
    • Muhammad Younas
    • Justyna Płotka-Wasylka
    2024 ChemistrySelect

    Multiwalled carbon nanotubes (MWCNTs) are well-known adsorbents because of their high surface area, layered and hollow architecture, hydrophobicity, and multiple and easily accessible adsorption sites. In this study, MWCNTs were used for dispersive micro-solid-phase extraction of various metal chelates in environmental and food samples. Different parameters such as concentration of the chelating reagent, the sorbent dosage, the extraction time, the desorption time, and the strength of the eluent were suitably optimized. Under the optimum extraction conditions, the proposed method demonstrated a good linear working range for all the analytes, with correlation coefficients above 0.9915. The limit of detection ranged from 0.02 to 0.21 μg/L. The inter-day and intra-day relative standard deviations were less than 2.5%. The proposed method was used for the determination of selected metals in tap water, drinking water, cucumber, and tomato samples. In the end, GAPI tool was used to evaluate the greenness of the method.

  • Diurnal variability of atmospheric water vapour, precipitation and cloud top temperature across the global tropics derived from satellite observations and GNSS technique
    • Zofia Baldysz
    • Grzegorz Nykiel
    • Dariusz Baranowski
    • Beata Latos
    • Mariusz Figurski
    2024 Pełny tekst CLIMATE DYNAMICS

    The diurnal cycle of convection plays an important role in clouds and water vapour distribution across the global tropics. In this study, we utilize integrated moisture derived from the global navigation satellite system (GNSS), satellite precipitation estimates from TRMM and merged infrared dataset to investigate links between variability in tropospheric moisture, clouds development and precipitation at a diurnal time scale. Over 16 years of observations were analysed to estimate the diurnal cycles for 42 sites that span across the global tropics and assess the GNSS precipitable water vapour suitability in tropical moisture variability studies. Results show that the GNSS technique can be successfully used for studies related to the high-resolution temporal variability of integrated atmospheric moisture and, thus, in the analysis of multi-scale interactions and clouds development. For most of the analysed cases, GNSS integrated humidity shows one daily maximum (regardless of the season), which is related to the afternoon precipitation and cloud top temperature daily minimum. Although diurnal integrated moisture variations typically do not exceed 2 mm (usually below 5% of the daily mean value), in favourable large-scale conditions such relatively small changes can lead to the development of convective clouds and can affect precipitation distribution. Thus, GNSS technology allows reliable monitoring of tropospheric moisture variability at a diurnal time scale, which can be leveraged for improved monitoring and prediction of high-impact weather.

  • Divide and not forget: Ensemble of selectively trained experts in Continual Learning
    • Grzegorz Rypeść
    • Sebastian Cygert
    • Valeriya Khan
    • Tomasz Trzciński
    • Bartosz Zieliński
    • Bartłomiej Twardowski
    2024 Pełny tekst

    Class-incremental learning is becoming more popular as it helps models widen their applicability while not forgetting what they already know. A trend in this area is to use a mixture-of-expert technique, where different models work together to solve the task. However, the experts are usually trained all at once using whole task data, which makes them all prone to forgetting and increasing computational burden. To address this limitation, we introduce a novel approach named SEED. SEED selects only one, the most optimal expert for a considered task, and uses data from this task to fine-tune only this expert. For this purpose, each expert represents each class with a Gaussian distribution, and the optimal expert is selected based on the similarity of those distributions. Consequently, SEED increases diversity and heterogeneity within the experts while maintaining the high stability of this ensemble method. The extensive experiments demonstrate that SEED achieves state-of-the-art performance in exemplar-free settings across various scenarios, showing the potential of expert diversification through data in continual learning.

  • Do clusters help companies to "go green"? Experience of Polish National Key Clusters
    • Anna Lis
    • Marta Mackiewicz
    • Anna Wendt
    2024

    This study aims to explore cluster activity in the field of green transformation, taking into account the green, low-carbon and circular economy. Our intention was to identify the main green practices used by cluster organizations, which we showed through the lens of the attributes of both the cluster and the cluster organization. Through our study, we sought to answer the question: what is the role of cluster organizations in supporting green transformation from the perspective of both cluster coordinators and members? The study was conducted in the period 2021-2023 mainly in Polish National Key Clusters. The selection of clusters was based, on the one hand, on the similarity resulting from their maturity (which was determined, among others, by the age and the scope of activities), on the other hand, on the differences resulting from industry affiliation and location (surveyed clusters represent different industries and are located in different parts of Poland). We conducted a two-stage quantitative survey in which we assessed cluster green transformation activity from the perspective of cluster managers (first stage) and from the perspective of cluster enterprise representatives (second stage), using the same survey questionnaire. Our study showed that for the development of cluster cooperation within green transformation, the role of geographical proximity is crucial. It was with this cluster attribute that the most popular green practices identified in the study were linked. They are associated with relationship building, learning and knowledge sharing processes, and growth of innovation potential.

  • Do personality traits influence the user’s behavioral intention to adopt and use Open Government Data (OGD)? An empirical investigation
    • Nina Rizun
    • Charalampos Harris Alexopoulos
    • Stuti Saxena
    • Fernando Kleiman
    • Ricardo Matheus
    2024 TELEMATICS AND INFORMATICS

    The academic interest in the Open Government Data (OGD) domain has been burgeoning over the years. Conceding that the prime focus of an OGD initiative is its further re-use for value creation and innovation by stakeholders, the present study seeks to underscore the role of HEXACO personality traits on behavioral intention (BI) to adopt and use OGD in developing countries' context. We investigate the direct, indirect, and moderating effects of HEXACO personality traits provide a better understanding of how and to what extent personality traits influence future behavioral intention to use OGD. The results demonstrate that Trust and Performance Expectancy are positive predictors of BI to adopt and use OGD. Users with higher Openness to Experience tend to have higher Effort and Performance Expectancy; are characterized by exposure to Social Influence; have higher level of Trust and positive experience of Facilitating Conditions and Information Quality. Agreeable people are more likely to Voluntarily Use OGD. Conscientiousness enhances the individual's perception of OGD quality-related factors. Excessive Emotionality affects negative perception to System and Information Quality issues. Honesty–Humility and Extraversion are able to maintain the effect of OGD Information Quality and Trust on users' BI. Our findings could be useful for practitioners to level the divergence between actual and potential use of OGD by considering the user's personality traits

  • Do You Know What You Drink? Comparative Research on the Contents of Radioisotopes and Heavy Metals in Different Types of Tea from Various Parts of the World
    • Grządka Elżbieta
    • Anna Bastrzyk
    • Jolanta Orzeł
    • Agata Oszczak-Nowińska,
    • Bartłomiej Fliszkiewicz
    • Mateusz Siemieniuk
    • Krzysztof Sobczyński
    • Olgierd Spławski
    • Katarzyna Gołębiewska
    • Oskar Ronda
    • Bartłomiej Cieślik
    2024 Pełny tekst Foods

    The aim of this study was to assess the potential health risks of radioactive elements and heavy metals ingested through the consumption of various types of tea imported to the Polish market (black, green, red, oolong and white). The concentrations [Bq/kg] of radionuclides (40K, 137Cs, 226Ra, 210Pb and 228Th) in tea leaves before and after brewing were measured using γ-ray spectrometry with high-purity germanium (HPGe). The concentrations [mg/kg] of the studied elements (Fe, Cr, Cu, Mo, Al, Mn, Ni, P, V, Cd and Pb) were determined using a microwave-induced plasma optical emission spectrometer (MIP-OES). The results presented here will help to expand the database of heavy metals and radioactivity in teas. With regard to the potential health risk, the percentage of leaching of individual elements in different types of tea infusions was determined, and the assessment of the consumption risk was estimated. Since the calculated exposure factors, namely the HQ (Hazard Quotient) and THQ (Target Hazard Quotient), do not exceed critical levels, teas can still be considered health-beneficial products (most of the radionuclides as well as elements remain in the leaves (65–80%) after brewing).

  • Docieranie i szlifowanie powierzchni płasko-równoległych na docierarkach tarczowych
    • Adam Barylski
    2024 Kwartalnik Naukowo-Techniczny "Obróbka Metalu"

    W artykule przedstawiono aktualny stan techniki i technologii docierania powierzchni płasko-równoległych na docierarkach dwutarczowych oraz sposób obróbki przez szlifowanie na tych obrabiarkach. Omówiono warunki kinematyczne docierania obiegowego, sposób chłodzenia tarcz docierających oraz możliwe ich zużycie profilowe. Podano przykłady obróbki cześci maszynowych. Charakteryzowano wydajność docierania i szlifowania, uzyskiwane parametry chropowatości powierzchni, sposób wyrównywania tarcza docierających i ściernic oraz budowę narzędzi segmentowych i nasypem diamentowym. Podano zalety szlifowania z kinematyką docierania obiegowego.

  • Double Bias of Mistakes: Essence, Consequences, and Measurement Method
    • Wioleta Kucharska
    • Aleksandra Kopytko
    2024 Pełny tekst Electronic Journal on Business Research Methods

    There is no learning without mistakes. However, there is a clash between‘positive attitudes and beliefs’regarding learning processes and the ‘negative attitudes and beliefs’towardthese being accompanied bymistakes. Thisclash exposesa cognitive bias towardmistakesthat might block personal and organizational learning. This study presents an advanced measurement method to assess thebias of mistakes. The essence of it is the detection of the existing contradictionsbetween attitude and behavior towardmistakes at the personal and organizational levels,as well as combined.This study is based on empirical evidence from a sample of 768 knowledge workers, divided into biased and non-biased subsamples following the procedure proposed in this paper. Those subsamples were next applied to the structural model, examining knowledge,learning, and collaboration cultures (the KLC approach) 's influence on organizational intelligence to validate the proposed method. Results showed that the applied method efficiently detects the DBM and exposes that in doubly mistakes-biased knowledge-driven organizations, the influence of knowledge culture on the mistakes acceptance component of learning culture is negative. So, organizations with a dominated double bias of mistakes do not accept the affirmation of learning from mistakes.Summing up, this study constitutes the Double Bias of Mistakes Theory, which states that the clash between positive attitudes and beliefs regarding learning processes and negative attitudes and beliefs toward mistakes exposed by focusing on control managers (bosses) might block organizational learning from mistakes and, as a consequence, negatively affect organizational intelligence. Without the empirical support for this theory, there was a risk that the idea of accepting mistakes as a potential source of learning would be simplified by biased minds to mistakes tolerance and rejected as ridiculous. Accepting that mistakes can be a source of precious learning does not equal mistake tolerance. On the contrary, it is the first step to managing mistakes and creating efficient error avoidance systems thanks to lessons learned from failures. This study introduces the method of measurement and detection of theDouble Bias of Mistakes phenomenon, contributing to the science of organizational learning and collective intelligence-building.

  • Drinking water safety evaluation in the selected sub-Saharan African countries: A case study of Madagascar, Uganda and Rwanda
    • Małgorzata Szopińska
    • Wojciech Artichowicz
    • Danuta Szumińska
    • Daniel Kasprowicz
    • Żaneta Polkowska
    • Sylwia Fudala-Książek
    • Aneta Łuczkiewicz
    2024 SCIENCE OF THE TOTAL ENVIRONMENT

    In the sub-Saharan region of Africa, access to safe drinking water remains limited in many countries. This study provides an overview of the quality of surface water and groundwater in rural and peri-urban areas of Madagascar, Uganda, and Rwanda. Selected physico-chemical parameters, inorganic species (including inorganic ions), and organic pollution indicators, such as total organic carbon, non-ionic surfactants, cationic surfactants, anionic surfactants, sum of phenolic compounds and formaldehyde, were analysed. Principal component analysis was applied to assess the variability of the water quality and identify regional dependencies. The inorganic ion composition in the majority of the studied samples meets WHO and EU requirements for drinking water intended for human consumption and poses no human health risk. However, an individual non-cancer-causing health index for nitrates and the values of Water Quality Index show a possible threat of ingesting the studied drinking water. The presence of surfactants (0.1–0.65 mgL-1), phenolic compounds (0.025–1.76 mgL-1) and formaldehyde (0.04–0.32 mgL-1) may also pose a risk to human, animal, and aquatic life. Additionally, in-situ measurements for E. coli and Total Coliforms conducted during the last field campaign in Madagascar (2022) revealed that all studied drinking water sources ranged from intermediate risk to unsafe. This result calls for the urgent need to enhance WASH (water, sanitation, and hygiene) services in the studied areas. The presence of both chemical and microbiological pollutants shows the need for the local authorities to develop and implement a catchment management plan to ensure the protection of water resources from potential pollution, and raise community awareness about the impact of human activity on water resources.

  • Dual-Activity Fluoroquinolone-Transportan 10 Conjugates offer alternative Leukemia therapy during Hematopoietic Cell Transplantation
    • Jan Lica
    • Mateusz Heldt
    • Miłosz Wieczór
    • Paweł Chodnicki
    • Natalia Ptaszyńska
    • Anna Łęgowska
    • Wioletta Brankiewicz
    • Katarzyna Gucwa
    • Anna Stupak
    • Natalia Maciejewska
    • Bhaskar Pradhan
    • Agata Gitlin-Domagalska
    • Dawid Dębowski
    • Sławomir Milewski
    • Maria Bieniaszewska
    • Grzegorz Jan Grabe
    • Andrzej Hellmann
    • Rolka Krzysztof
    2024 MOLECULAR PHARMACOLOGY

    Hematopoietic cell transplantation (HCT) is often considered a last resort leukemia treatment, fraught with limited success due to microbial infections, a leading cause of mortality in leukemia patients. To address this critical issue, we explored a novel approach by synthesizing antileukemic agents containing antibacterial substances. This innovative strategy involves conjugating fluoroquinolone antibiotics, such as ciprofloxacin (CIP) or levofloxacin (LVX), with the cell-penetrating peptide (CPP) transportan 10 (TP10). Here, we demonstrate that the resultant compounds display promising biological activities in preclinical studies. These novel conjugates not only exhibit potent antimicrobial effects but are also selective against leukemia cells. The cytotoxic mechanism involves rapid disruption of cell membrane asymmetry leading to membrane damage. Importantly, these conjugates penetrated mammalian cells, accumulating within the nuclear membrane without significant effect on cellular architecture or mitochondrial function. Molecular simulations elucidated the aggregation tendencies of TP10 conjugates within lipid bilayers, resulting in membrane disruption and permeabilization. Moreover, mass spectrometry analysis confirmed efficient reduction of disulfide bonds within TP10 conjugates, facilitating release and activation of the fluoroquinolone derivatives. Intriguingly, these compounds inhibited human topoisomerases, setting them apart from traditional fluoroquinolones. Remarkably, TP10 conjugates generated lower intracellular levels of reactive oxygen species (ROS) compared to CIP and LVX. The combination of antibacterial and antileukemic properties, coupled with selective cytostatic effects and minimal toxicity towards healthy cells, positions TP10 derivatives as promising candidates for innovative therapeutic approaches in the context of antileukemic HCT. This study highlights their potential in search of more effective leukemia treatments.

  • Dual-band Millimetre Wave MIMO Antenna with Reduced Mutual Coupling Based on Optimized Parasitic Structure and Ground Modification
    • Bashar Esmail
    • Dustin Isleifson
    • Sławomir Kozieł
    2024 Pełny tekst Scientific Reports

    In this study, a high-isolation dual-band (28/38 GHz) multiple-input–multiple-output (MIMO) antenna for 5G millimeter-wave applications is presented. The antenna consists of two interconnected patches. The primary patch is connected to the inset feed, while the secondary patch is arc-shaped and positioned over the main patch, opposite to the feed. Both patches function in the lower 28 GHz band, while the primary patch is accountable for inducing the upper 38 GHz band. An expedited trust-region (TR) algorithm is employed to optimize the dimensions of the antenna components, ensuring the antenna operates efficiently with high reflection at both bands. The antenna demonstrates a gain exceeding 7 dBi at both frequencies. An array of four antennas is configured orthogonally to create a MIMO system with isolation surpassing 19 dB. The isolation is further enhanced through the addition of a circular parasitic patch at the front and modifications made to the ground. The TR method is employed again to optimize their parameters and achieve the desired isolation, exceeding 32 dB at both bands. The MIMO system demonstrates outstanding diversity performance at both frequencies, characterized by low values of the envelope correlation coefficient (ECC) (<10−4), channel capacity loss (CCL) (<0.03 bit/s/Hz), and total active reflection coefficient (TARC) (<−10 dB). Additionally, it secures a diversity gain (DG) exceeding 9.99 dB. The MIMO system is manufactured and tested, showing good alignment between simulation and measurement data for all performance metrics.