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  • Financial Consequences of the Introduction of the Fit For 55 on the Example of Poland
    • Justyna Kujawska
    • Piotr Kasprzak
    2023

    In Europe and in Poland, there is a growing conviction that climate action is a necessity. When creating long-term strategies or making current decisions, companies are increasingly taking into account issues related to sustainable development and reducing CO2 emissions. Following the signing of the Paris Agreement in 2015, countries around the world pledged to reduce greenhouse gas emissions by 2050 so that the average temperature increase does not exceed 2°C, with the ambition to reach 1.5°C. EU countries have agreed to tighten climate regulations by adopting and implementing the Fit For 55 package. The aim of this study is to present the financial consequences of the introduction of the Fit For 55 package of regulations. The Fit for 55 package is related to Europe's energy transition and is at the initial stage of implementation, hence the lack of broader studies on the subject. The research method includes an analysis of available reports estimating the economic impact of the Fit for 55 package and statistical information. The research shows that the costs of Polish's energy transformation will be very high (over € 500 billion), which is only an estimate, taking into account the current level of prices and knowledge, because many technologies to be used are only at the research stage. For most EU countries, this will entail the introduction of new taxes, fees, as well as legal and administrative restrictions, which will undoubtedly result in higher prices of individual goods and services. In addition, the introduced regulations will lead to the cessation of the use of certain technologies, e.g. combustion cars, coal-fired power plants, or a reduction in the turnover of, for example, real estate that does not meet certain energy efficiency requirements.

  • Finite element modeling of plastic hinges based on ductility demand-capacity method using nonlinear material for dynamic analysis
    • Karol Grębowski
    • Krzysztof Wilde
    • Mikołaj Miśkiewicz
    2023 Pełny tekst INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING

    The article discusses modeling plastic hinges in reinforced concrete interme-diate supports using finite elements methods. The ductility demand-capacitymethod was used to determine the geometrical parameters of cross-section plas-ticization zones, their ability to move and rotate, as well as their ductility. Dueto the varied geometry and stiffness of the supports and their nonlinear behav-ior under dynamic load, this method was concluded to be imperfect. Therefore,an improved algorithm was proposed by determining the main parameters ofplastic hinges depending on the degree of concrete degradation according toLubliner’s assumptions. The new algorithm has been implemented in the formof mathematical equations. It was subsequently used, at the structure designstage, to perform numerical calculations based on the finite element method.

  • Fire-induced spalling of ultra-high performance concrete: A systematic critical review
    • Mugahed Amran
    • Gunasekaran Murali
    • Marzena Kurpińska
    • Moncef L. Nehdi
    2023 CONSTRUCTION AND BUILDING MATERIALS

    Ultra-high performance concrete (UHPC) is a novel concrete class characterized by a compressive strength of more than 150 MPa. One of the most significant drawbacks of employing UHPC is that is very low permeability owing to its great compactness of dense structure increases the risk of fire-induced spalling. It is challenging for fire safety and structural engineers to predict and analyze this issue due to the lack of widely accepted and reliable models for concrete spalling. Therefore, understanding the fire-spalling characteristics of UHPC exposed to high temperature or fire is vital for ensuring the safety of a UHPC-based structural fire design. To date, the fireinduced spalling behaviour of UHPC has not been thoroughly investigated. To address this informational gap, this article aims to assess various aspects of UHPC by focusing on fire-induced spalling and its influencing factors, spalling mechanism, microstructure characterization, prevention measures, and mitigation strategies. Moreover, this critical review summarizes and evaluates the results of thermal spalling tests and fire-induced spalling modeling undertaken on UHPC in developing a manual regulation protocol. This paper aims to provide insights into improving the existing design guidelines for the fire-spalling-resistant design of UHPC members, this facilitating wide-scale adoption of robust and sustainable UHPC. Given the merits of the study topic, the review strategies and initiatives can then be leveraged to give insight into areas that will be highly beneficial for future experiments and research of UHPC applications by research centers and construction industries globally.

  • Flexible syngas-biogas-hydrogen fueling spark-ignition engine behaviors with optimized fuel compositions and control parameters
    • Van Ga Bui
    • Thi Minh Tu Bui
    • Van Nam Tran
    • Zuohua Huang
    • Anh Tuan Hoang
    • Wiesław Tarełko
    • Van Hung Bui
    • Xuan Mai Pham
    • Phuoc Quy Phong Nguyen
    2023 Pełny tekst INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

    This paper presents the results research on the optimal fuel compositions and the control parameters of the spark ignition engine fueled with syngas-biogas-hydrogen for the purpose of setting up a flexible electronic control unit for the engine working in a solar-biomass hybrid renewable energy system. In syngas-biogas-hydrogen mixture, the optimal content of hydrogen and biogas is 20% and 30%, respectively. Exceeding these thresholds, the improvement of engine performance is moderate, but the pollution emission increases strongly. The optimal advanced ignition angle is 38°CA, 24°CA, and 18°CA for syngas, biogas, and hydrogen, respectively. With the same content of hydrogen or biogas in the mixture with syngas, the advanced ignition angle of the hydrogen-syngas blend is less than that of the syngas-biogas blend by about 4°CA at the engine speed of 3000 rpm. The derating power of the engine is 30% and 23% as switching from the hydrogen and biogas fueling mode to the syngas fueling mode, respectively. However, NOx emission of the engine increase from 200 ppm (for syngas) to 2800 ppm (for biogas) and to over 6000 ppm (for hydrogen). The optimal advanced ignition angle, the optimal equivalence ratio of the syngas-biogas-hydrogen fuel mixture vary within the limits of the respective values for syngas and hydrogen. To improve the engine efficiency and reduce pollutant emissions, the loading control system of the engine should prioritize the adjustment of the fuel flow and then the adjustment of the air-fuel mixture flow.

  • Flood Modelling and Risk Analysis of Cinan Feizuo Flood Protection Area, Huaihe River Basin
    • Umar Farooq
    • Abubakr Taha Bakheit Taha
    • Fuchang Tian
    • Ximin Yuan
    • Muhammad Ajmal
    • Irfan Ullah
    • Mahmood Ahmad
    2023 Pełny tekst Atmosphere

    This study evaluated multiple aspects of flood risks and effects on the Cinan Feizuo flood protection area in the Huaihe River basin. Flooding remains a leading problem for infrastructure, especially in urban, residential areas of the region. Effective flood modeling for urbanized floodplains is challenging, but MIKE (ID-2D) is paramount for analyzing and quantifying the risk in the vulnerable region. The Saint-Venant equation and a one-dimensional (1D) MIKE 11 model were used to understand the flood dynamics in the Huaihe River, and a two-dimensional (2D) MIKE 21 model was applied to assess the risk in the Cinan Feizuo flood protection area. The finite volume method (FVM) was used for discrete grid problems, and the models were coupled through the weir equation to find the flow volume from the 1D domain to the 2D domain to investigate water level changes. Flood inundation maps were generated for the flood protection area. The maximum discharge, velocity, and submerged depth for 50- and 100-year flood events were assessed with flood risk. Chenbei indicated a high flood risk level in 50 to 100 years in which the water level exceeds a high level and inundates the maximum area with minimum time. Conversely, the 100-year flood inundation in the flood protection area was comparatively higher than the 50-year flood, with a lower time step. The risk analysis identified significant damage caused by the flood over the target regions. The findings of this study provide technical support for flood risk analysis and loss assessment within the flood protection area and have important reference values for regional flood control, disaster reduction decision making, and constructive planning.

  • Flow boiling of R1233zd(E) in a 3 mm vertical tube at moderate and high reduced pressures
    • Michał Pysz
    • Dariusz Mikielewicz
    2023 Pełny tekst EXPERIMENTAL THERMAL AND FLUID SCIENCE

    The results of flow boiling of R1233zd(E) in a 3 mm vertical stainless steel tube are presented at moderate and high saturation temperatures. Integral flow characteristics in the form of pressure drop and heat transfer coefficient are discussed for saturation temperatures ranging from 115 to 145 °C (corresponding reduced pressures from 0.2 to 0.7), mass velocity of 800 kg/m2s and heat flux of 20 kW/m2. All of the obtained heat transfer trends initially decrease with vapor quality and then do not change or increase with vapor quality. The decrease is connected to the dominance of the nucleate boiling phenomenon. The subsequent increase in heat transfer indicates the increased effect of convective boiling. The rate of the increase depends on the value of reduced pressure (the smaller the reduced pressure the higher the rate). The obtained data have been compared with the predictions of the in-house model and some well-known two-phase flow correlations. The in-house model predictions presented the highest accuracy, with MAPE equal to 23.17 % for R1233zd(E) and 19.23 % for R245fa (data from literature).

  • Flow Maps and Flow Patterns of R1233zd(E) in a Circular Minichannel at Low, Medium and High Values of Saturation Pressure
    • Stanisław Głuch
    • Michał Pysz
    • Dariusz Mikielewicz
    2023 Pełny tekst

    There is a gap in knowledge regarding the flow pattern of low-boiling working fluids in the range of high saturation temperatures (above 120°C) and medium and high reduced pressures (0.5-0.9). Data are present in the literature for similar values of reduced pressures, but for lower values of saturation temperature. This is due to the existing refrigeration applications of these working fluids. At high values of reduced pressure, the density of the gas phase is relatively high, and the density of the liquid phase is low. There is a low specific volume difference between the liquid and gas phases. The liquid phase has a low surface tension value. The gas phase has a relatively high viscosity, and the liquid phase has a reduced value of viscosity. These changes in the parameters of refrigerants cause significant differences in flow structures. At a low value of reduced pressure, 0.2, the occurrence of annular flow was observed already at a quality of 0.07 for a mass velocity of G=355 [kg/(m^2·s)], while for a reduced pressure of 0.8, annular flow occurs much later, at a quality of 0.47 for the same mass velocity. Mass velocity flow maps in a function of quality for constant values of reduced pressure and flow maps for reduced pressure as a function of quality at constant mass velocity are presented. Flow maps are compared with correlations for transition lines between intermittent and annular flow structures from literature. Authors new correlation for transition line for researched conditions is presented. New prediction method is the only one which managed to predict transition to annular flow at high values of reduced pressure for collected experimental data.

  • Fluid–solid interaction on a thin platelet with high-velocity flow: vibration modelling and experiment
    • Piotr Ziolkowski
    • Tomasz Ochrymiuk
    • Victor Eremeev
    2023 Pełny tekst CONTINUUM MECHANICS AND THERMODYNAMICS

    The paper concerns the nonlinear behaviour of a thin platelet that is streamlined in an aerodynamic tunnel. The air velocity in the aerodynamic tunnel was at 858.9 km/h or 0.7 Ma (Ma—Mach number is a dimensionless quantity in fluid dynamics representing the ratio of flow velocity past a boundary to the local speed of sound). This experiment was numerically simulated using FSI (fluid–solid interaction) tools, namely the coupling between the strength and flow code. The strength code uses the finite element method, while the flow code is based on the finite volume method. The coupling between the codes was made by means of an interface that transmitted the relevant data and results between the two codes. The paper discusses the methodology of this coupling. The study also highlights the phenomena occurring during the interaction of flow with the plate with emphasis on their nonlinear character.

  • FORECASTING BIOGAS FORMATION IN LANDFILLS
    • Zbigniew Kneba
    • Jacek Kropiwnicki
    • Jakub Hadrzyński
    • Maciej Ziółkowski
    2023 Pełny tekst Acta Mechanica et Automatica

    : The aim of the present research was to develop a mathematical model for estimating the amount of viscous gas generated as a function of weather conditions. Due to the lack of models for predicting gas formation caused by sudden changes in weather conditions in the literature, such a model was developed in this study using the parameters of landfills recorded for over a year. The effect of temperature on landfill gas production has proved to be of particular interest. We constructed an algorithm for calculating the amount of the produced gas. The model developed in this study could improve the power control of the landfill power plant.

  • Four Degree-of-Freedom Hydrodynamic Maneuvering Model of a Small Azipod-Actuated Ship With Application to Onboard Decision Support Systems
    • Mathias Marley
    • Roger Skjetne
    • Mateusz Gil
    • Przemysław Krata
    2023 Pełny tekst IEEE Access

    The main contribution of this paper is a numerical ship motion model of NTNU’s research vessel Gunnerus, capturing the surge, sway, roll, and yaw dynamics when sailing in uniform and steady currents. The model utilizes a crossflow drag formulation for the transverse viscous loads, and it includes a nonlinear formulation for the propulsion and steering loads provided by two azipod thrusters. A wide range of experimental data obtained from sea trials are used for model calibration and validation. The model is intended for development of Decision Support Systems (DSS) that provide the helmsman with recommendations for safe maneuvers. As a demonstration, the model is used to generate input to a previously proposed DSS solution, which uses offline simulations to create a database of the critical navigation area for different encounter scenarios. Additionally, we propose a DSS solution that uses online simulations to predict the future ship trajectory under guidance of a virtual autopilot. The virtual autopilot is designed using a novel hybrid control barrier function formulation to predict the need of evasive maneuvers for collision avoidance.

  • Fractographical quantitative analysis of EN-AW 2024 aluminum alloy after creep pre-strain and LCF loading
    • Wojciech Macek
    • Adam Tomczyk
    • Ricardo Branco
    • Michał Dobrzyński
    • Andrzej Seweryn
    2023 ENGINEERING FRACTURE MECHANICS

    This paper explores the applicability of a new damage parameter combining both fracture surface topography and loading features to estimate the fatigue lifetime under creep pre-strain and low-cycle fatigue loading. Fractures of EN-AW 2024 aluminum alloy caused by mixed creep and low-cycle fatigue loading are experimentally characterized and quantified via surface topography analysis. The specimens were preliminary damaged in a creep process at elevated temperature (100 °C, 200 °C, or 300 °C) considering two strain levels for each temperature. The specimens with preliminary damage were then subjected to fatigue tests at room temperature. The post-failure fracture surfaces were examined with an optical profilometer, and the focus was placed on the relationship between the creep-fatigue damage and the associated fracture surface topography parameters. In addition, an original fatigue life prediction model based on both the surface topography values and the applied strains was proposed and verified. The proposed model can be helpful for post-mortem analysis of engineering components subjected to fatigue loading accounting for creep pre-strain.

  • Fractographic-fractal dimension correlation with crack initiation and fatigue life for notched aluminium alloys under bending load
    • Wojciech Macek
    • Dariusz Rozumek
    • Sebastian Faszynka
    • Ricardo Branco
    • Shun-Peng Zhu
    • Reza Masoudi Nejad
    2023 Pełny tekst ENGINEERING FAILURE ANALYSIS

    In this study, fatigue fracture surfaces of aluminium alloy 2017-T4 notched specimens were investigated under cyclic bending to find an alternative failure loading index.. The surface topographies were measured on the entire fracture area with an optical profilometer for different loading conditions. Fatigue crack initiation life Ni and total fatigue life Nf were examined using standard surface topography parameters (such as, root mean square height Sq, arithmetical mean height Sa, maximum height Sz) and non-standard surface topography parameters (such as, fractal dimension Df). Fatigue life assessment was successfully performed by combining both fracture surface topography and stress state features. The results show that the fracture plane geometry, expressed by the fractographic-fractal dimension, can facilitate the estimation of post-failure loading history.

  • Fracture Surface Topography Parameters for S235JR Steel Adhesive Joints After Fatigue Shear Testing
    • Andrzej Kubit
    • Wojciech Macek
    • Władysław Zielecki
    • Paulina Szawara
    • Mariusz Kłonica
    2023 Pełny tekst Advances in Science and Technology Research Journal

    This paper presents the experimental results of a study investigating the effect of holes and notches made on the overlap ends on the strength of adhesive joints. Single-lap joints made of S235JR steel sheets bonded with Araldite 2024-2 epoxy adhesive were tested. For comparative reasons, static shear strength tests and high-cycle fatigue strength tests were performed. Adhesive-filled joints having three holes, each with a diameter of 3 mm, and notches, each 3 mm wide and 4 mm long, were tested and compared with reference joints, i.e. without modification. The assumption was to determine whether the structural modifications would reduce the peak peel and shear stresses that are typical of this type of joints. Results of the static strength tests showed no significant effect of the applied modifications on the strength of the joints. However, in terms of fatigue strength, the results demonstrated a significant improvement in fatigue life, the value of which increased in the low-cycle fatigue region by 328.6% for the joint with notches and by 640.8% for the joint with holes. A smaller yet still positive effect of the applied modifications was shown for high-cycle fatigue. For a variable load with the maximum value of 9 MPa, the fatigue life increased by 215.9% for the variant with notches and by 183.3% for the variant with holes. Surface topography of fatigue fractures was examined by determining roughness parameters on the overlap ends in the samples. Significant differences were shown, with the selected roughness parameters being significantly lower for the reference variant than for the variants with notches and holes. It was shown that the applied structural modifications led to increasing the fatigue strength to 8.5 MPa for the limit number of cycles equal to 2×106, when compared to the reference variant for which the fatigue strength was 8 MPa.

  • Free trade with the former COMECON Countries as Unequal Exchange
    • Marta Kuc-Czarnecka
    • Magdalena Olczyk
    • Andrea Saltelli,
    • Erik, S. Reinert
    2023 Pełny tekst

    Two authors of this chapter were born to the East of what was once The Iron Curtain and two to the West. From both angles, the two systems – capitalism and communism – seemed to be as contrary to each other as possible. Few people are aware that in terms of industrial and trade policy, both classical capitalism and communism had a common root in the theories of German economist Friedrich List (1789-1846) (List, 1841). In fact, for the 200th anniversary of his birth in 1989, both East Germany (DDR) and West Germany (Deutsche Bundespost) celebrated Friedrich List's anniversary with postage-stamps. The two enemies who had split Germany between them even chose the same portrait of their common hero! However, after the collapse of the Berlin Wall, the policy that was forced upon the former COMECON countries was not the old capitalism honoured by West Germany in 1989. Capitalist theory (but not practice) had given way to neoliberalism, a system that does not see any difference between economic activities. The theory that came out as a winner at the end of the Cold War was essentially David Ricardo's (1817) theory of international trade, restated by US economist Paul Samuelson (1948). Samuelson 'proved' that free trade, regardless of what was traded, would create a movement towards factor-price equalization (that the price of the factors of production, capital and labour) would tend to equalize across the globe. This neoliberal theory was immediately forced upon the former communist countries, leading to different degrees of deindustrialization.

  • Free volume in physical absorption of carbon dioxide in ionic liquids: Molecular dynamics supported modeling
    • Joachim Eichenlaub
    • Karol Baran
    • Maciej Śmiechowski
    • Adam Kloskowski
    2023 SEPARATION AND PURIFICATION TECHNOLOGY

    Understanding the mechanisms underlying the carbon dioxide (CO2) absorption in ionic liquids (ILs) is the key to their efficient utilization in industrial flue gas treatment. One of the parameters considered substantially important in the process is the Free Volume. In this study, the Fractional Free Volume (FFV) of 73 ILs was calculated using Molecular Dynamics (MD). A quantitative Structure-Property Relationship (QSPR) study was then employed to predict the FFV, but the validation parameters were unsatisfactory. In the second part, the importance of Free Volume in the absorption of CO2 in ILs was assessed by creating two models to predict Henry’s Law Constant of CO2 in ILs. It was found that the addition of the FFV parameter considerably improved the statistical parameters and predictability of the QSPR model. Furthermore, FFV was found to be heavily dependent on the cation type and its inclusion allowed for the determination of more subtle molecular interactions.

  • Frequency measurement research with weight averaging of pulse output signal of voltage-to-frequency converter
    • Mykhaylo Dorozhovets
    • Eligiusz Pawłowski
    • Dariusz Świsulski
    2023 MEASUREMENT

    The paper presents the essence and investigation of the efficiency of weight averaging of a pulse output signal of voltage-to-frequency converter. The effect of counting and the influence of interference on the result of weight averaging of frequency modulated pulses are analyzed. It is shown that from the point of view of counting error reduction, the best are polynomial weight functions. In the case of high interferences whose frequencies are unstable or may change over a wide range, the specified level of their suppression, together with the reduction of the counting effect, can be achieved using weight functions, such as trigonometric. The interference suppression both in the narrow and wide frequency ranges, as well as the counting error when using selected weight functions, have been tested by both simulation and experimentally. The obtained results show very good convergence with the values calculated from theoretical formulas.

  • Frequency Selective Surface Based MIMO Antenna Array for 5G Millimeter-Wave Applications
    • Iftikhar Din
    • Mohammad Alibakhshikenari
    • Bal S. Virdee
    • Renu Karthick Rajaguru Jayanthi
    • Sadiq Ullah
    • Chan Hwang See
    • Salahuddin Khan
    • Sławomir Kozieł
    • Sławomir Kozieł
    2023 Pełny tekst SENSORS

    Abstract: In this paper a radiating element consisting of a modified circular patch is proposed for MIMO arrays for 5G millimeter-wave applications. The radiating elements in the proposed 2×2 MIMO antenna array are orthogonally configured relative to each other to mitigate mutual coupling that would otherwise degrade the performance of the MIMO system. The MIMO array was fabri-cated on Rogers RT/Duroid high frequency substrate with dielectric constant of 2.2, thickness of 0.8 mm and loss tangent of 0.0009. The individual antenna in the array has a measured impedance bandwidth of 1.6 GHz from 27.25 to 28.85 GHz for S11 ≤ −10 dB, and the MIMO array has a gain of 7.2 dBi at 28 GHz with inter radiator isolation of greater than 26 dB. The gain of the MIMO array was increased by introducing frequency selective surface (FSS) consisting of 7×7 array of unit cells comprising rectangular C-shaped resonators one embedded inside the other with a central criss-cross slotted patch. With the FSS the gain of the MIMO array increased to 7.6 dBi at 28 GHz. The radiation from the array is directional and perpendicular to the plain of the MIMO array. Owing to the low coupling between the radiating elements in the MIMO array its Envelope Correlation Coefficient (ECC) is less than 0.002 and Diversity Gain (DG) is better than 9.99 dB in the 5G oper-ating band centered at 28 GHz between 26.5 GHz and 29.5 GHz.

  • Friction Stir Welding of Aluminum in the Aerospace Industry: The Current Progress and State-of-the-Art Review
    • Mohamed M. Z. Ahmed
    • Mohamed M. El-Sayed Seleman
    • Dariusz Fydrych
    • Gürel Çam
    2023 Pełny tekst Materials

    The use of the friction stir welding (FSW) process as a relatively new solid-state welding technology in the aerospace industry has pushed forward several developments in different related aspects of this strategic industry. In terms of the FSW process itself, due to the geometric limitations involved in the conventional FSW process, many variants have been required over time to suit the different types of geometries and structures, which has resulted in the development of numerous variants such as refill friction stir spot welding (RFSSW), stationary shoulder friction stir welding (SSFSW), and bobbin tool friction stir welding (BTFSW). In terms of FSW machines, significant development has occurred in the new design and adaptation of the existing machining equipment through the use of their structures or the new and specially designed FSW heads. In terms of the most used materials in the aerospace industry, there has been development of new high strength-to-weight ratios such as the 3rd generation aluminum–lithium alloys that have become successfully weldable by FSW with fewer welding defects and a significant improvement in the weld quality and geometric accuracy. The purpose of this article is to summarize the state of knowledge regarding the application of the FSW process to join materials used in the aerospace industry and to identify gaps in the state of the art. This work describes the fundamental techniques and tools necessary to make soundly welded joints. Typical applications of FSW processes are surveyed, including friction stir spot welding, RFSSW, SSFSW, BTFSW, and underwater FSW. Conclusions and suggestions for future development are proposed

  • From Scores to Predictions in Multi-Label Classification: Neural Thresholding Strategies
    • Karol Draszawka
    • Julian Szymański
    2023 Pełny tekst Applied Sciences-Basel

    In this paper, we propose a novel approach for obtaining predictions from per-class scores to improve the accuracy of multi-label classification systems. In a multi-label classification task, the expected output is a set of predicted labels per each testing sample. Typically, these predictions are calculated by implicit or explicit thresholding of per-class real-valued scores: classes with scores exceeding a given threshold value are added to a prediction set. In our work, we propose a neural network-based thresholding phase for multi-label classification systems and examine its influence on the overall classification performance measured by micro- and macro-averaged F1 scores on synthetic and real datasets. In contrast to classic thresholding methods, our approach has the unique property of being able to recover from scoring errors, because each decision about a given label prediction depends on the corresponding class score, as well as on all the other class scores for a given sample at once. The method can be used in combination with any classification system that outputs real-valued class scores. The proposed thresholding methods are trained offline, after the completion of the scoring phase. As such, it can be considered a universal fine-tuning step that can be employed in any multi-label classification system that seeks to find the best multi-label predictions based on class scores. In our experiments on real datasets, the input class scores were obtained from two third-party baseline classification systems. We show that our approach outperforms the traditional thresholding methods, which results in the improved performance of all tested multi-label classification tasks. In terms of relative improvement, on real datasets, the micro-F1 score is higher by up to 40.6%, the macro-F1 score is higher by up to 3.6%, and the averaged micro–macro-F1 score is higher by up to 30.1%, considering single models only. We show that ensembles and hybrid models give even better results. We show examples of successful extreme recoveries, where the system, equipped with our method, was able to correctly predict labels, which were highly underscored after the scoring phase.

  • Frontem do morza. Plan, budowa i architektura portu w Gdyni
    • Anna Orchowska
    2023

    Gdynia to port, a port to Gdynia. Tak na początku istnienia II Rzeczpospolitej ukształtowała się jej morska stolica. Monografia Anny Orchowskiej to pierwsza publikacja poświęcona całokształtowi jednej z największych realizacji międzywojnia. Realizacji, która nie tylko pełniła istotne funkcje gospodarcze, ale też szybko stała się wizytówką kraju. Zwrócone niejako frontem do morza budynki były awangardowe i śmiałe w formie. Budowane w duchu modernizmu, doskonale wpisywały się w światowe trendy lat dwudziestych i trzydziestych XX wieku. Autorka – jako architekt i historyk architektury – analizuje jakość zastosowanych w porcie rozwiązań zarówno estetycznych, jak i technicznych i technologicznych. Nie pomija także czynnika ludzkiego. Port nie powstałby przecież bez inicjatorów i organizatorów morskich przedsięwzięć, projektantów, inżynierów, budowniczych, a wreszcie – bez zwykłych pracowników. Czy udało im się stworzyć dzieło ponadczasowe?

  • Frontier education for a sustainable future - speculative design in architecture as a transdisciplinary experiment
    • Lucyna Nyka
    • Elżbieta Marczak
    2023 Pełny tekst Global Journal of Engineering Education

    In this article, the authors propose the term frontier education referring to the well-established notion of frontier research - one, that through opening unexpected transdisciplinary perspectives, may offer new insights and create a fertile ground for new discoveries and ground-breaking concepts. In answer to the question of how to get rid of normative thinking and extend architectural experimentations, a speculative design architectural studio was proposed to students of Gdańsk University of Technology (Gdańsk Tech), Gdańsk, Poland, in collaboration with a non-academic foresight institution. In this article, the authors discuss the effects of introducing the speculative design methodology as a transdisciplinary and frontier education experiment. They reflect on how this kind of experimentation contributed to enriching the student’s understanding of the constant process of adaptation of architecture to environmental challenges, social trends and technological innovations.

  • FTIR, Raman spectroscopy and HT-XRD in compatibility study between naproxen and excipients
    • Barbara Rojek
    • Maria Gazda
    • Anna Plenis
    2023 SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY

    Detection of incompatibility between an active pharmaceutical ingredient (API) and excipients, including the selection of the most biopharmaceutical advantageous excipients is extremely important in the pre-formulation process of developing a solid dosage form technology. Therefore, having fast and reliable methods for identifying incompatibility is fundamental in pharmaceutical technology. For this purpose, combined Fourier transform infrared (FTIR) and Raman spectroscopy as well as high-temperature X-ray diffraction (HT-XRD) were used as a new approach for incompatibility detection, whereas differential scanning calorimetry (DSC) was applied as a reference method. In addition, to facilitate the interpretation of FTIR and Raman data, a multivariate analysis was used – hierarchical cluster analysis (HCA). The tests were carried out in mixtures of naproxen (NPX) with eight selected polymer excipients, mixed at a 1:1 ratio. The results of spectroscopic analyses have shown the physical incompatibility of NPX with methylcellulose (MC), hydroxypropylmethylcellulose (HPMC), hydroxyethylcellulose (HEC), sodium starch glycolate (SSG) and sodium carboxymethylcellulose (CMC). HT-XRD studies performed when these mixtures were heated to 156 °C and then cooled to 25 °C showed a decrease in naproxen crystallinity in these mixtures. Furthermore, the results obtained with spectroscopic methods were confirmed by DSC tests and an intrinsic dissolution rate study.

  • Fuel systems of high power stationary engine
    • Zbigniew Kneba
    2023 Pełny tekst Combustion Engines

    The use of alternative fuels and, in the future, synthetic fuels has forced changes in the design of fuel supply systems in internal combustion engines. When operating a stationary engine at constant load, the possibility of using lean fuel mixtures appears. The selection of a precise operating mixture ignition system requires changes in traditional fuel systems. The article presents the current designs of fuel supply systems and their properties. Attention was paid to operating parameters resulting in acceptable emissions of toxic exhaust gas components

  • Full-field in vivo experimental study of the strains of a breathing human abdominal wall with intra-abdominal pressure variation
    • Katarzyna Szepietowska
    • Mateusz Troka
    • Monika Lichodziejewska-Niemierko
    • Michał Chmielewski
    • Izabela Lubowiecka
    2023 Journal of the Mechanical Behavior of Biomedical Materials

    The presented study aims to assess the mechanical behaviour of the anterior abdominal wall based on an in vivo experiment on humans. Full-field measurement of abdominal wall displacement during changes of intra-abdominal pressure is performed using a digital image correlation (DIC) system. Continuous measurement in time enables the observation of changes in the strain field during breathing. The understanding of the mechanical behaviour of a living human abdominal wall is important for the proper design of surgical meshes used for ventral hernia repair, which was also a motivation for the research presented below. The research refers to the strain field of a loaded abdominal wall and presents the evolution of principal strains and their directions in the case of 12 subjects, 8 male and 4 female. Peritoneal dialysis procedure allows for the measurement of intra-abdominal pressure after fluid introduction. High variability among patients is observed, also in terms of principal strain direction. Subjects exhibit intra-abdominal pressure of values from 11 to 21 cmH2O. However, the strain values are not strongly correlated with the pressure value, indicated variability of material properties.

  • Fungal co-culture improves the biodegradation of hydrophobic VOCs gas mixtures in conventional biofilters and biotrickling filters
    • Milena Marycz
    • Anna Brillowska-Dąbrowska
    • Sara Cantera
    • Jacek Gębicki
    • Raúl Muñoz
    2023 CHEMOSPHERE

    The present study systematically evaluated the potential of Candida subhashii, Fusarium solani and their consortium for the abatement of n-hexane, trichloroethylene (TCE), toluene and α-pinene in biofilters (BFs) and biotrickling filters (BTFs). Three 3.2 L BFs packed with polyurethane foam and operated at a gas residence time of 77 s with an air mixture of hydrophobic volatile organic compounds (VOCs) were inoculated with C. subhashii, F. solani and a combination of thereof. The systems were also operated under a BTF configuration with a liquid recirculating rate of 2.5 L h-1. Steady state elimination capacities (ECs) of total VOCs of 17.4 ± 0.7 g m−3 h−1 for C. subhashii, 21.2 ± 0.8 g m−3 h−1 for F. solani and 24.4 ± 1.4 g m−3 h−1 for their consortium were recorded in BFs, which increased up to 27.2 ± 1.6 g m−3 h−1, 29.2 ± 1.9 g m−3 h−1, 37.7 ± 3.3 g m−3 h−1 in BTFs. BTFs supported a superior biodegradation performance compared to BF, regardless of the VOCs. Moreover, a more effective VOC biodegradation was observed when C. subhashii and F. solani were grown as a consortium. The microbial analysis conducted revealed that the fungi initially introduced in each BF represented the dominant species by the end of the experiment, with C. subhashii gradually overcoming F. solani in the system inoculated with the fungal consortium.

  • Fusion-based Representation Learning Model for Multimode User-generated Social Network Content
    • Arsalan Muhammad Soomar
    2023 ACM Journal of Data and Information Quality

    As mobile networks and APPs are developed, user-generated content (UGC), which includes multi-source heterogeneous data like user reviews, tags, scores, images, and videos, has become an essential basis for improving the quality of personalized services. Due to the multi-source heterogeneous nature of the data, big data fusion offers both promise and drawbacks. With the rise of mobile networks and applications, UGC, which includes multi-source heterogeneous data including ratings, marks, scores, images, and videos, has gained importance. This information is very important for improving the calibre of customized services. The key to the application's success is representational learning of fusing and vectorization on the multi-source heterogeneous UGC. Multi-source text fusion and representation learning have become the key to its application. In this regard, a fusion representation learning for multi-source text and image is proposed. The convolutional fusion technique, in contrast to splicing and fusion, may take into consideration the varied data characteristics in each size. This research proposes a new data feature fusion strategy based on the convolution operation, which was inspired by the convolutional neural network. Using Doc2vec and LDA model, the vectorized representation of multi-source text is given, and the deep convolutional network is used to obtain it. Finally, the proposed algorithm is applied to Amazon's commodity dataset containing UGC content based on the classification accuracy of UGC vectorized representation items and shows the feasibility and impact of the proposed algorithm

  • g-C3N4 for Photocatalytic Degradation of Parabens: Precursors Influence, the Radiation Source and Simultaneous Ozonation Evaluation
    • Eryk Fernandes
    • Paweł Mazierski
    • Tomasz Klimczuk
    • Adriana Zaleska-Medynska
    • Rui F. Martins
    • João Gomes
    2023 Pełny tekst Catalysts

    Graphitic carbon nitride (g-C3N4) is a promising catalyst for contaminants of emerging concern removal applications, especially as a visible-light-driven material. In this study, g-C3N4 catalysts were effectively synthesized through a simple thermal polymerization method, using melamine, urea, and thiourea as precursors to elucidate the influence of these compounds on the final product’s photocatalytic performance. The degradation of a mixture of three parabens was investigated under different types of radiation: two artificial, ultraviolet-A (UVA) and visible LED, and natural sunlight. The urea-based catalyst (UCN) presented better results under all radiation sources, followed by thiourea, and finally, melamine. Among the artificial light sources, the degradation of parabens under UVA was considerably higher than visible—up to 51% and 21%, respectively—using UCN; however, the broader spectrum of natural sunlight was able to achieve the highest removals, up to 92%, using UCN. Comparing artificial radiation sources, UVA lamps presented 45% lower energy consumption and associated costs. Photocatalytic ozonation was tested using UCN and MCN, with UCN once more possessing superior performance and a synergetic effect between photocatalysis and ozonation, with complete removal under 12 min. The use of g-C3N4 was then successfully tested in initial screening and found to be an efficient alternative in more low-cost and feasible solar photocatalysis water treatment.

  • Gdynia, wczesnomodernistyczne centrum miasta
    • Maria Sołtysik
    • Robert Hirsch
    • Marek Stępa
    2023

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  • Gelatin and gelatin/starch-based films modified with sorbitol for wound healing
    • Justyna Kozłowska
    • Joanna Skopińska-Wiśniewska
    • Beata Kaczmarek-Szczepańska
    • Sylwia Grabska-Zielińska
    • Balbina Makurat-Kasprolewicz
    • Anna Michno
    • Anna Ronowska
    • Marcin Wekwejt
    2023 Journal of the Mechanical Behavior of Biomedical Materials

    Gelatin-based films modified with sorbitol were produced from gelatin solution or gelatin/starch blends using a simple and low-cost solvent casting method, and subsequently, their physicochemical, mechanical, and biocompatibility properties were characterized. This work focused on developing and optimizing a biopolymeric blend to improve the pure biopolymers’ properties for potential biomedical applications such as wound dressing. The films were characterized in terms of morphology and transparency, mechanical, moisture and swelling properties, thermal stability, and degradation potential. Moreover, hemocompatibility, as well as cytocompatibility of prepared films, were examined. The addition of sorbitol contributed to improving mechanical properties, swelling reduction, and increasing biostability over time. The cytocompatibility of obtained films was confirmed in vitro with two different human cell lines, fibroblastic and osteoblastic, and a more favorable cellular response was received for fibroblasts. Further, in hemocompatibility studies, it was found that all films may be classified as non-hemolytic as they did not have a negative effect on the human erythrocytes. The obtained results indicate the great potential of the gelatin/starch blends modified with sorbitol as regenerative biomaterials intended for wound healing applications.

  • Gender Disparity in the FinTech Sector: Systematic Literature Review
    • Błażej Prusak
    • Łukasz Wacławek
    2023

    The main objective of this chapter is to identify research areas of FinTech activity in which gender disparity has been observed. In addition, we shall identify how the development of FinTech reduces the gender gap. A systematic literature review using the PRISMA concept is the preferred research method. Publications were searched in the following databases: Web of Science, Scopus and Google Scholar using the formula “FinTech AND gender”. After removing less significant records from the Google Scholar database and performing a screening, a detailed literature analysis was carried out on the basis of 22 publications. The research shows that the topic of gender disparity in FinTech is relatively little recognised as: the oldest publications date back to 2018, there are few publications in the major databases, and the topic is often covered as a side issue. Five areas were identified in the research on gender disparity in FinTech: (1) FinTech and entrepreneurship; (2) FinTech and wages/earnings; (3) FinTech and CEOs/managers; (4) FinTech and the role of women in society; and (5) FinTech and users. The main findings of the research are: gender discrimination can be observed: among FinTech managers and users of certain services; in the intention of people of both genders to use certain services; and in the software used by FinTech institutions. In turn, the positive impact of the development of the FinTech sector relates to reducing the gender wage gap, increasing the level of entrepreneurship and the social status of women.

  • General Provisioning Strategy for Local Specialized Cloud Computing Environments
    • Piotr Orzechowski
    • Henryk Krawczyk
    2023 Pełny tekst

    The well-known management strategies in cloud computing based on SLA requirements are considered. A deterministic parallel provisioning algorithm has been prepared and used to show its behavior for three different requirements: load balancing, consolidation, and fault tolerance. The impact of these strategies on the total execution time of different sets of services is analyzed for randomly chosen sets of data. This makes it possible to improve the project and to implement the proper strategies for the local TASKcloud environment used in our institution.

  • Generalization of Phylogenetic Matching Metrics with Experimental Tests of Practical Advantages
    • Damian Bogdanowicz
    • Krzysztof Giaro
    2023 Pełny tekst JOURNAL OF COMPUTATIONAL BIOLOGY

    The ability to quantify a dissimilarity of different phylogenetic trees is required in various types of phylogenetic studies, for example, such metrics are used to assess the quality of phylogeny construction methods and to define optimization criteria in supertree building algorithms. In this article, starting from the already described concept of matching metrics, we define three new metrics for rooted phylogenetic trees. One of them, Matching Pair Jaccard (MPJ) distance, is still purely topological, but we now utilize the Jaccard index set dissimilarity measure in its construction. This modification substantially changes the structural features of the metric space. In particular, we investigate the properties of the previously known Matching Cluster Jaccard (MCJ) and the new MPJ metrics, such as the asymptotic behavior of their expected distance between two random trees, the space diameter, and the change of a distance after a single leaf relocation. The other two metrics, Matching Cluster Weight-aware (MCW) and Matching Cluster Jaccard Weight-aware (MCJW) distances, are the first propositions of generalization of matching metrics designed for rooted phylogenies with branch lengths. The experimental tests of the practical utility of the phylogenetic metrics show the superiority of MCJ, MPJ over the previous best tree comparison method. To define the MCW and MCJW metrics, we introduce a general method for constructing matching metrics for weighted rooted phylogenetic trees.

  • Generalized Einstein relation in disordered organic semiconductors: Influence of the acoustic phonons–charge carriers scattering
    • Jędrzej Szmytkowski
    2023 COMPUTATIONAL MATERIALS SCIENCE

    In this work, we analyze the generalized Einstein relation for disordered organic semiconductors with a non-equilibrium Druyvesteyn-type distribution function. The Druyvesteyn behavior of hot electrons in a solid state is associated with the acoustic phonons–charge carriers scattering. Such a case has been experimentally demonstrated in electroluminescent inorganic rare–earth–doped zinc chalcogenides. Therefore, we can assume that, in a part of organic materials used in organic light-emitting diodes (OLEDs), we can also find the Druyvesteyn-type distribution of charge carriers under external electric fields. It looks that the electric-field-dependent diffusion coefficient, which is observed in the phonon-induced hopping electron transport, plays a key role here. The theoretical analysis of the Einstein relation shows that for lower concentrations of charge carriers, the diffusivity–mobility ratio (D/\mu) reaches a value lower than 1 (in kT/q units). The temperature dependencies of D/\mu are similar to the tendencies reported for the equilibrium conditions. The obtained satisfactory agreement between experimental results and calculations based on the Druyvesteyn-type distribution function confirms the usefulness of the presented model.

  • Generating actionable evidence from free-text feedback to improve maternity and acute hospital experiences: A computational text analytics & predictive modelling approach
    • Adegboyega Ojo
    • Nina Rizun
    • Mona Isazad Mashinchi
    • Grace Walsh
    • Jon Gruda
    • Manohar Narayana Narayana
    • Maria Venosa
    • Conor Foley
    • Daniela Rohde
    • Rachel Flynn
    2023 EUROPEAN JOURNAL OF PUBLIC HEALTH

    Background Patient experience surveys are a key source of evidence for supporting decision-making and quality improvement in healthcare services. These surveys contain two main types of questions: closed and open-ended, asking about patients’ care experiences. Apart from the knowledge obtained from analysing closed-ended questions, invaluable insights can be gleaned from free-text data. Advanced analytics techniques are increasingly used to harness free-text data, yet existing approaches do not offer the rigour required to support formal decision-making through free-text. Methods This study addresses the challenge of effectively and rigorously analysing patients’ free-text feedback to improve maternity and acute hospital services in Ireland. Aspects of healthcare services (i.e. themes) that could be improved were determined using computational text analytics and predictive modelling. Themes extracted from comments were prioritised based on volume, the intensity of negative affect expressed in the texts, and the estimated influence of the themes on overall patient satisfaction. Results Results demonstrate the viability of producing rigorous evidence for prioritising interventions to improve healthcare services based on free-text feedback. Specifically, consistency in advice and support in breastfeeding were among the most important issues for maternity services. For acute hospital services, meals quality and access, A&E waiting time, ward hygiene and communication at discharge were among the most important issues. Women also wanted more emphasis on prior birth experience and complications in future maternity care surveys. Conclusions Advances in computational text modelling enable the extraction of concrete and actionable insights from the analysis of free-text data. This approach also allows decision-makers to prioritise emergent themes and inform actions that will positively impact overall patient satisfaction

  • Genome-Wide DNA Methylation and Gene Expression in Patients with Indolent Systemic Mastocytosis
    • Aleksandra Górska
    • Maria Urbanowicz
    • Łukasz Grochowalski
    • Michał Seweryn
    • Marta Sobalska-Kwapis
    • Tomasz K. Wojdacz
    • Magdalena Lange
    • Marta Gruchała-Niedoszytko
    • Justyna Jarczak
    • Dominik Strapagiel
    • Magdalena Górska-Ponikowska
    • Iwona Pelikant-Malecka
    • Leszek Kalinowski
    • Bogusław Nedoszytko
    • Danuta Gutowska-Owsiak
    • Marek Niedoszytko
    2023 Pełny tekst INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES

    Mastocytosis is a clinically heterogenous, usually acquired disease of the mast cells with a survival time that depends on the time of onset. It ranges from skin-limited to systemic disease, including indolent and more aggressive variants. The presence of the oncogenic KIT p. D816V gene somatic mutation is a crucial element in the pathogenesis. However, further epigenetic regulation may also affect the expression of genes that are relevant to the pathology. Epigenetic alterations are re-sponsible for regulating the expression of genes that do not modify the DNA sequence. In general, it is accepted that DNA methylation inhibits the binding of transcription factors, thereby down-regulating gene expression. However, so far, little is known about the epigenetic factors leading to the clinical onset of mastocytosis. Therefore, it is essential to identify possible epigenetic predictors, indicators of disease progression, and their link to the clinical picture to establish appropriate management and a therapeutic strategy. The aim of this study was to analyze genome-wide methylation profiles to identify differentially methylated regions (DMRs) in patients with mastocytosis compared to healthy individuals, as well as the genes located in those regulatory regions. Genome-wide DNA methylation profiling was performed in peripheral blood collected from 80 adult patients with indolent systemic mastocytosis (ISM), the most prevalent subvariant of mastocytosis, and 40 healthy adult volunteers. A total of 117 DNA samples met the criteria for the bisulfide conversion step and microarray analysis. Genome-wide DNA methylation analysis was performed using a MethylationEPIC BeadChip kit. Further analysis was focused on the genomic regions rather than individual CpG sites. Co-methylated regions (CMRs) were assigned via the CoMeBack method. To identify DMRs between the groups, a linear regression model with age as the covariate on CMRs was performed using Limma. Using the available data for cases only, an association analysis was performed between methylation status and tryptase levels, as well as the context of allergy, and anaphylaxis. KEGG pathway mapping was used to identify genes differentially expressed in anaphylaxis. Based on the DNA methylation results, the expression of 18 genes was then analyzed via real-time PCR in 20 patients with mastocytosis and 20 healthy adults. A comparison of the genome-wide DNA methylation profile between the mastocytosis patients and ...

  • Geosyntetyki w konstrukcji drogi kolejowej - modelowanie
    • Eligiusz Mieloszyk
    • Anita Milewska
    • Sławomir Grulkowski
    2023

    Geosyntetyki, tzn. geowłókniny, geotkaniny, geosiatki, geomembrany, geowykładziny itp. są powszechnie stosowane w budownictwie, w tym przy budowie, modernizacji i remontach linii transportowych: przesyłowych (rurociągi), komunikacyjnych (drogi kolejowe, drogi kołowe itp.). Liniowe budowle transportowe mają charakter wielowarstwowy, przez co każda kolejna warstwa posiada inne warunki obciążenia. W wyniku działających na drogę kolejową obciążeń w trakcie bieżącej eksploatacji następuje jej osiadanie, często nierównomierne. Z tego wynika, że zmieniają swoje położenie w czasie punkty leżące na geosyntetyku. W każdym przypadku w analizie ich zachowań możemy je traktować jako membrany sprężyste lub powłoki posadowione na różnych rodzajach podłoża. np. typu Winklera, Eulera, Pasternaka, Kerra, bowiem modelowanie układu rzeczywistego oznacza jego idealizację pod kątem uwzględnienia tych cech ośrodka, które wydają się najistotniejsze z punktu widzenia analizowanego problemu. Przedstawione rozważania uprawniają do wykorzystania utworzonych opisów matematycznych do modelowania zmian w czasie położenia punktów analizowanego obszaru Ω, a w szczególności interesujących nas punktów (x,y,g(x,y)) geosyntetyków, gdzie z=g(x,y) jest równaniem powierzchni geosyntetyku, natomiast (x,y) należą do zbioru D⊂R^2, który jest rzutem Ω na płaszczyznę XOY układu współrzędnych i punktów leżących w warstwach położonych dostatecznie blisko powierzchni geosyntetyku. Wielkości u(x,y,z,t) można wyznaczać numerycznie, a także z wykorzystaniem metod mieszanych na bazie przedstawionych wzorów lub stosować modele powłokowe MES. Można je wykorzystywać do badań symulacyjnych i eksperymentalnych. W celu przeprowadzenia identyfikacji modelu trzeba przeprowadzić badania eksperymentalne wykorzystując eksperyment czynny, bierny lub mieszany i przeprowadzić walidację modelu. Wykorzystując otrzymane wzory można prowadzić analizę ilościową i jakościową problemu, po przeprowadzeniu identyfikacji, kalibracji i walidacji modelu, najlepiej z wykorzystaniem badań in situ w celu określenia parametrów układu zastępczego. Analizę problemu dodatkowo komplikuje wzajemne oddziaływanie poszczególnych elementów konstrukcji drogi kolejowej. Np. nawierzchni kolejowej, podtorza z geosyntetykami i podłoża gruntowego. Jednak wyjściem z tej sytuacji może być wykorzystanie układów analogowych i zastępczych.

  • Giant Reed (Arundo donax L.) Fiber Extraction and Characterization for Its Use in Polymer Composites
    • Luis Suárez
    • Mateusz Barczewski
    • Paulina Kosmela
    • María D. Marrero
    2023 Pełny tekst Journal of Natural Fibers

    This work describes an extraction method for giant reed fibers from stems and leaves based on chemical soaking and crushing through a rolling mill. Obtained fibers, together with the shredded plant (stems + leaves), are characterized in terms of chemical composition, thermal stability, morphology, and crystallinity. Mechanical properties of fibers have also been assessed (single fiber tensile tests). The results show that the proposed method allows obtaining fibers with higher cellulose content (near 70%), good thermal stability (10% weight loss over 270°C), higher density, and better mechanical properties than other Arundo fibers previously reported in the literature. Fibers from leaves are thinner and show higher crystallinity than those from stems (72 μm vs. 157 μm, 73% vs. 67% crystallinity, respectively), although mechanical properties are similar for both (around 900 MPa for tensile strength and over 45 GPa for elastic modulus). Analysis of the microstructure shows that fibers consist of microfiber bundles, and the removal of a thin layer of non-cellulosic nature is clear; fibers provide a rougher, cleaner surface than shredded raw material.

  • GIS-based hydrodynamic modeling for urban flood mitigation in fast-growing regions: a case study of Erbil, Kurdistan Region of Iraq
    • Andam Mustafa
    • Michał Szydłowski
    • Mozafar Veysipanah
    • Hasan Mohammed Hameed
    2023 Pełny tekst Scientific Reports

    Floods threaten urban infrastructure, especially in residential neighborhoods and fast-growing regions. Flood hydrodynamic modeling helps identify flood-prone locations and improve mitigation plans' resilience. Urban floods pose special issues due to changing land cover and a lack of raw data. Using a GIS-based modeling interface, input files for the hydrodynamic model were developed. The physical basin's properties were identified using soil map data, Land Use Land Cover (LULC) maps, and a Digital Elevation Model (DEM). So, the HEC-RAS 2-D hydrodynamic model was developed to estimate flood susceptibility and vulnerability in Erbil, Iraq. The case study examines the quality of flood modeling results using different DEM precisions. Faced with the difficulty, this study examines two building representation techniques: Building Block (BB) and Building Resistance (BR). The work presented here reveals that it is possible to apply the BR technique within the HEC-RAS 2-D to create urban flood models for regions that have a lack of data or poor data quality. Indeed, the findings confirmed that the inundated areas or areas where water accumulated in past rainfall events in Erbil are the same as those identified in the numerical simulations. The study's results indicate that the Erbil city is susceptible to flood hazards, especially in areas with low-lying topography and substantial precipitation. The study's conclusions can be utilized to plan and develop flood control structures, since it identified flood-prone areas of the city.

  • Global Complex Roots and Poles Finding Algorithm in C × R Domain
    • Sebastian Dziedziewicz
    • Małgorzata Warecka
    • Rafał Lech
    • Piotr Kowalczyk
    2023 Pełny tekst IEEE Access

    An algorithm to find the roots and poles of a complex function depending on two arguments (one complex and one real) is proposed. Such problems are common in many fields of science for instance in electromagnetism, acoustics, stability analyses, spectroscopy, optics, and elementary particle physics. The proposed technique belongs to the class of global algorithms, gives a full picture of solutions in a fixed region  ⊂ C × R and can be very useful for preliminary analysis of the problem. The roots and poles are represented as curves in this domain. It is an efficient alternative not only to the complex plane zero search algorithms (which require multiple calls for different values of an additional real parameter) but also to tracking algorithms. The developed technique is based on the generalized Cauchy Argument Principle and Delaunay triangulation in three-dimensional space. The usefulness and effectiveness of the method are demonstrated on several examples concerning the analysis of guides (Anti-Resonant Reflecting Acoustic Waveguide, coaxially loaded cylindrical waveguide, graphene transmission line) and a resonant structure (Fabry-Pérot open resonator).

  • Global energy transition: From the main determinants to economic challenges regions
    • Adam P. Balcerzak
    • Gazi Salah Uddin
    • Bartosz Igliński
    • Michał Pietrzak
    2023 Pełny tekst EQUILIBRIUM Quarterly Journal of Economics and Economic Policy

    Dynamic global energy transition has been accelerating for the last decade. Interestingly, the energy transition is multidimensional and concerns both the dimensions of technique/ technology and the economic, social, institu-tional, and legal spheres (Shuguang et al., 2022; Tzeremes et al., 2022; Ram-zan et al., 2022; Tzeremes et al., 2022). The literature also points to the signif-icant impact of the digitization of the global economy on accelerating ener-gy transition processes (Shahbaz et al., 2022; Yi et al., 2022). It can be expected that due to the currently observed "Artificial Intelligence Revolu-tion," this factor may gain even higher importance. From the normative perspective, it is commonly assumed that the ener-gy transition should proceed according to the idea of the energy trilemma, which emphasizes three key aspects: ensuring energy security, fair access to energy, and environmental sustainability (Liu et al., 2022). However, reaching this objective is one of the biggest challenges for highly developed societies; specifically, supporting this process is the greatest challenge for current science.

  • Global value chains and wages under different wage setting mechanisms
    • Joanna Wolszczak-Derlacz
    • Dagmara Nikulin
    • Sabina Szymczak
    2023 Pełny tekst Competition & Change. The Journal of Global Business and Political Economy

    This study examines whether, and how, differences in wage bargaining schemes shape the relationship between global value chains (GVCs) and the wages of workers while considering both GVC participation and position in GVC. Our dataset is derived from the European Structure of Earnings Survey (SES), containing employee–employer data from 18 European countries, merged with sectoral data from the World Input-Output Database (WIOD). The results of an augmented Mincer-type regression show that under national and industry wage bargaining schemes, greater participation in GVCs is associated with lower wages, whereas no adverse impact from GVCs is observed for workers under enterprise bargaining schemes. Finally, numerous extensions and instrumental variable estimations confirm that the type of collective pay agreement may alter the response of wages to both GVC participation and position.

  • Globalized Knowledge-Based Simulation-Driven Antenna Miniaturization Using Domain-Confined Surrogates and Dimensionality Reduction
    • Sławomir Kozieł
    • Anna Pietrenko-Dąbrowska
    • Łukasz Gołuński
    2023 Pełny tekst Applied Sciences-Basel

    Design of contemporary antenna systems encounters multifold challenges, one of which is a limited size. Compact antennas are indispensable for the new fields of application such as inter-net of things or 5G/6G mobile communication. Still, miniaturization generally undermines elec-trical and field performance. When attempted through numerical optimization, it turns into a constrained problem with costly constraints requiring electromagnetic (EM) simulations. At the same time, due to parameter redundancy of compact antennas, size reduction poses a multimod-al task. In particular, the achievable miniaturization rate heavily depends on the starting point, while identifying a suitable starting point is a challenge on its own. These issues indicate that miniaturization should be addressed through global optimization methods. Unfortunately, the most popular nature-inspired algorithms cannot be applied for solving size reduction tasks be-cause of their inferior computational efficacy and difficulties in handling constraints. This work proposes a novel methodology for globalized size reduction of antenna structures. Our method-ology is a multi-stage knowledge-based procedure, initialized by detection of the approximate location of the feasible region boundary, followed by a construction of a dimensionali-ty-reduced metamodel, and global optimization thereof; the last stage is miniaturiza-tion-oriented local refinement of geometry parameters. For cost reduction, the first stages of the procedure are realized with the use of low-fidelity EM antenna model. Our approach is verified using four broadband microstrip antennas, and benchmarked against multi-start local search, as well as nature-inspired methods. Superior size reduction rates are demonstrated for all consid-ered cases, while maintaining reasonably low computational costs.

  • Gospodarka w dobie pandemii Covid-19. Wybrane zagadnienia
    • Elżbieta Kacperska
    • Krystyna Gomółka
    • Piotr Kasprzak
    • Łukasiewicz Katarzyna
    • Jarosław Wróblewski
    2023

    Monografia ukazuje problemy gospodarek Polski , Kazachstanu i Ukrainy w okresie pandemii Covid-19 oraz programy naprawcze które podjęły rządy tych państw by zmniejszyć skutki wywołane lockdownem i spowolnieniem gospodarczym.

  • Grafo-mania, czyli rzecz o grafach i algorytmach. Gry chromatyczne na grafach.
    • Marek Kubale
    2023 Pismo PG

    W minieseju analizujemy grę 2-osobową, polegającą na tym, że Alicja i Bogdan współdziałają by pomalować mapę narysowaną na płaszczyźnie.

  • Graph Neural Networks and Structural Information on Ionic Liquids: A Cheminformatics Study on Molecular Physicochemical Property Prediction
    • Karol Baran
    • Adam Kloskowski
    2023 Pełny tekst JOURNAL OF PHYSICAL CHEMISTRY B

    Ionic liquids (ILs) provide a promising solution in many industrial applications, such as solvents, absorbents, electrolytes, catalysts, lubricants, and many others. However, due to the enormous variety of their structures, uncovering or designing those with optimal attributes requires expensive and exhaustive simulations and experiments. For these reasons, searching for an efficient theoretical tool for finding the relationship between the IL structure and properties has been the subject of many research studies. Recently, special attention has been paid to machine learning tools, especially multilayer perceptron and convolutional neural networks, among many other algorithms in the field of artificial neural networks. For the latter, graph neural networks (GNNs) seem to be a powerful cheminformatic tool yet not well enough studied for dual molecular systems such as ILs. In this work, the usage of GNNs in structure–property studies is critically evaluated for predicting the density, viscosity, and surface tension of ILs. The problem of data availability and integrity is discussed to show how well GNNs deal with mislabeled chemical data. Providing more training data is proven to be more important than ensuring that they are immaculate. Great attention is paid to how GNNs process different ions to give graph transformations and electrostatic information. Clues on how GNNs should be applied to predict the properties of ILs are provided. Differences, especially regarding handling mislabeled data, favoring the use of GNNs over classical quantitative structure–property models are discussed.

  • Graphene Production and Biomedical Applications: A Review
    • Klaudia Malisz
    • Beata Świeczko-Żurek
    2023 Pełny tekst Crystals

    Graphene is a two-dimensional nanomaterial composed of carbon atoms with sp2 hybrid orbitals. Both graphene and graphene-based composite have gained broad interest among researchers because of their outstanding physiochemical, mechanical, and biological properties. Graphene production techniques are divided into top-down and bottom-up synthesis methods, of which chemical vapor deposition (CVD) is the most popular. The biomedical applications of graphene and its composite include its use in sensors, implantology, and gene and drug delivery. They can be used for tissue engineering, anticancer therapies, and as antimicrobial agents in implant application. The biocompatibility of graphene-based nanomaterials enables their use in the field of biomedicine. This article reviews the properties of graphene, the methods used to produce it, the challenges associated with its use, and the potential applications of this material in biomedicine, regenerative medicine, and drug delivery systems.

  • Great Resignation and Quiet Quitting as Post-pandemic Dangers to Knowledge Management
    • Krzysztof Zięba
    2023 Pełny tekst

    Purpose: COVID-19 pandemic aftermaths include the emergence of new tendencies, such as the Quiet Quitting, and continuation of trends such as the Great Resignation, both of which have multiple knowledge-related impacts on individual, organizational and even national level. The aim of this paper is to show the mechanisms behind the Quiet Quitting and the Great Resignation from individual and organizational perspectives. Understanding them is the first step to developing remedies and building business resilience. Methodology: The paper uses systems thinking approach to analyse the phenomena of the Quiet Quitting. Causal loop diagrams are used to show the mechanisms behind those tendencies, their antecedents and the impact they have on several aspects of business operation and management. Findings: The Quiet Quitting and the Great Resignation are multifaceted phenomena and pose several knowledge-related dangers to organizations, including disturbed knowledge flows, knowledge loss, diminished efficiency, lost informal friendship networks, and knowledge leakage to competition. Causal loop diagram indicates that complicated relations between various elements may produce surprising and unexpected outcomes. It presents also opportunities to use leverage points in order to substantially reduce negative outcomes. Research limitations: The paper is of a conceptual nature. In order to transform causal loop diagrams into full systems thinking models extensive data is required. Hence this paper is intended as a basis for further research. Practical implications: The understanding of mechanisms behind the Great Resignation and the Quiet Quitting is crucial for managers trying to develop strategies that would tackle those problems. The papers shows what leverage points can be used to mitigate risks of their adverse impact on business organizations. Originality/value: The Great Resignation and the Quiet Quitting are often perceived as results of the COVID-19 pandemic, yet data suggest they remain strong also in the post-pandemic business reality. The paper offers a holistic approach to those phenomena using individual and organisational perspectives. It provides important insights into their nature, which can be useful to numerous stakeholders, including knowledge workers, managers and business owners.

  • Green and Sustainable Membranes: A review
    • Navid Rabiee
    • Rajni Sharma
    • Sahar Foorginezhad
    • Maryam Jouyandeh
    • Mohsen Asadnia
    • Mohammad Rabiee
    • Omid Akhavan
    • Eder C. Lima
    • Krzysztof Formela
    • Milad Ashrafizadeh
    • Zari Fallah
    • Mahnaz Hassanpour
    • Abbas Mohammadi
    • Mohammad Saeb
    2023 Pełny tekst ENVIRONMENTAL RESEARCH

    Membranes are ubiquitous tools for modern water treatment technology that critically eliminate hazardous materials such as organic, inorganic, heavy metals, and biomedical pollutants. Nowadays, nano-membranes are of particular interest for myriad applications such as water treatment, desalination, ion exchange, ion concentration control, and several kinds of biomedical applications. However, this state-of-the-art technology suffers from some drawbacks, e.g., toxicity and fouling of contaminants, which makes the synthesis of green and sustainable membranes indeed safety-threatening. Typically, sustainability, non-toxicity, performance optimization, and commercialization are concerns centered on manufacturing green synthesized membranes. Thus, critical issues related to toxicity, biosafety, and mechanistic aspects of green-synthesized nano-membranes have to be systematically and comprehensively reviewed and discussed. Herein we evaluate various aspects of green nano-membranes in terms of their synthesis, characterization, recycling, and commercialization aspects. Nanomaterials intended for nano-membrane development are classified in view of their chemistry/synthesis, advantages, and limitations. Indeed, attaining prominent adsorption capacity and selectivity in green-synthesized nano-membranes requires multi-objective optimization of a number of materials and manufacturing parameters. In addition, the efficacy and removal performance of green nano-membranes are analyzed theoretically and experimentally to provide researchers and manufacturers with a comprehensive image of green nano-membrane efficiency under real environmental conditions.

  • Green Approaches in Rubber Recycling Technologies: Present Status and Future Perspective
    • Paulina Wiśniewska
    • Józef Haponiuk
    • Xavier Colom
    • Mohammad Saeb
    2023 Pełny tekst ACS Sustainable Chemistry & Engineering

    As a consequence of massive production and consumption of rubbers, rubber blends, and rubber composites for myriad applications, elastomeric products have enormously accumulated and become an environmental threat. The disposal and burning of rubber wastes have been banned because of environmental and economic reasons. By contrast, a great deal of attention has been directed toward strategies enabling recycling and reuse of rubbers. Basically, conventional recycling methods suffer from several drawbacks such as the formation of dust, fumes, and toxic gases in the air, as well as contamination of underground water resources. Thus, green and sustainable formulations and processing methods nowadays are of priority and importance. Taking advantage of sustainable development horizons, scientific and technological aspects of waste rubber management such as processing techniques, properties of the resulting products, industrial applications, and compatibilization with other materials such as thermoplastics, thermosets, and rubbers are herein reviewed and discussed. A particular emphasis is placed on reactive extrusion as a highly flexible in situ compounding method enabling innovations and taking care of sustainability concerns. Finally, the current status of green rubber recycling and future opening doors ahead of this technology are highlighted.

  • Green sample preparation 2023
    • Francisco Pena-Pereira
    • Verónica Pino
    • Marek Tobiszewski
    • Lorena Vidal
    2023 Pełny tekst Advances in Sample Preparation

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