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High Frequency Conducted Emission in AC Motor Drives Fed By Frequency Converters: Sources and Propagation Paths
PublikacjaProvides a concise and thorough reference for designing electrical and electronic systems that employ adjustable speed drives Electrical and electronic systems that employ adjustable speed drives are being increasingly used in present-day automation applications. They are considered by many application engineers as one of the most interfering components, especially in a contemporarily faced industrial environment. This book fills...
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Global EM-Driven Optimization of Multi-Band Antennas Using Knowledge-Based Inverse Response-Feature Surrogates
PublikacjaElectromagnetic simulation tools have been playing an increasing role in the design of contemporary antenna structures. The employment of electromagnetic analysis ensures reliability of evaluating antenna characteristics but also incurs considerable computational expenses whenever massive simulations are involved (e.g., parametric optimization, uncertainty quantification). This high cost is the most serious bottleneck of simulation-driven...
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Janusz Nieznański prof. dr hab. inż.
OsobyUrodził się w 1957 r. w Gdańsku. Jest absolwentem Wydziału Elektrycznego Politechniki Gdańskiej (1981). W 1990 r. uzyskał stopień doktora, w 1999 r. stopień doktora habilitowanego, a w 2015 r. tytuł profesora. Jest pracownikiem naukowo-dydaktycznym Politechniki Gdańskiej nieprzerwanie od ukończenia studiów. Jego zainteresowania naukowe obejmują sterowanie, diagnostykę, modelowanie i symulację układów energoelektronicznych i napędowych,...
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Computer Controlled Systems Lab - 2023/2024
Kursy OnlineComputer Controlled Systems Lab The course includes 5 individual projects and their laboratory implementation. The topics:- Job analysis and tuning digital servo- Usage of a PC computer and MatLab package for controlling the dynamic object as a model of the tethered helicopter- Use of C language and the PC to control the plant in real time- Use of assembly language, and a microcontroller to control the plant in real time- Use...
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Computer Controlled Systems Lab - Nowy - Nowy
Kursy OnlineComputer Controlled Systems Lab The course includes 5 individual projects and their laboratory implementation. The topics:- Job analysis and tuning digital servo- Usage of a PC computer and MatLab package for controlling the dynamic object as a model of the tethered helicopter- Use of C language and the PC to control the plant in real time- Use of assembly language, and a microcontroller to control the plant in real time- Use...
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Effects of social media communication on brand equity and brand purchase intention
PublikacjaThe author studied the effect of two different social media communication on brand equity and brand purchase intention. A total of 504 data sets were generated through a standardized online-survey and analysed with structural equation modeling. The results of the empirical study showed that both firm-created and user-generated social media communication influenced brand equity, consequently impacting brand purchase intention. This...
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Creating Acoustic Maps Employing Supercomputing Cluster
PublikacjaThe implemented online urban noise pollution monitoring system is presented with regard to its conceptual assumptions and technical realization. A concept of the noise source parameters dynamic assessment is introduced. The idea of noise modeling, based on noise emission characteristics and emission simulations, was developer and practically utilized in the system. Furthermore, the working system architecture and the data acquisition...
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On the acoustic backscattering by Baltic herring and sprat
PublikacjaAccurate abundance estimate of Baltic clupeids, herring and sprat, is required for theirsustainable exploitation. The understanding the sound backscattering of individual fish isimportant for employing the acoustical techniques, which are widely used in the estimation.The previous studies demonstrated that the improvement of the understanding is critical forthe Baltic herring and sprat. It was the main...
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Rapid Yield Estimation and Optimization of Microwave Structures Exploiting Feature-Based Statistical Analysis
PublikacjaIn this paper, we propose a simple, yet reliable methodology to expediteyield estimation and optimization of microwave structures. In our approach,the analysis of the entire response of the structure at hand (e.g., $S$-parameters asa function of frequency) is replaced by response surface modeling of suitablyselected feature points. On the one hand, this is sufficient to determinewhether a design satisfies given performance specifications....
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The algorithm of building the hierarchical contextual framework of textual corpora
PublikacjaThis paper presents an approach for Modeling the Latent Semantic Relations. The approach is based on advantages of two computational approaches: Latent Semantic Analysis and Latent Dirichlet Allocation. The scientific question about the possibility of reducing the influence of these Methods limitation on the Quality of the Latent Semantic Relations Analysis Results is raised. The case study for building the Two-level Hierarchical Contextual...
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Influence of pulse waves on the transmission of near-infrared radiation in outer-head tissue layers.
PublikacjaIn this study, we investigate the effect of pulse waves on the transmission of near-infrared radiation in the outer tissue layers of the human head. This effect is important in using optical radiation to monitor brain conditions based on measuring the transmission changes in the near-infrared radiation between the source and the detector, placed on the surface of the scalp. This is because the signal related to the changes in the...
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Comparison of elastic and viscoelastic analysis of asphalt pavement at high temperature
PublikacjaThere are many various rheological models which are used for modeling of asphalt layers in flexible pavement structures. It can be expected that the use of various models may affect different results of mechanical pavement calculations and analysis. The paper presents comparison of the use of Burgers’ and Huet-Sayegh’s viscoelastic models and Hooke’s elastic model to calculate pavement deflections and strains at the bottom of asphalt...
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Particle Shape Effect on Macroscopic Behaviour of Underground Structures: Numerical and Experimental Study
PublikacjaThe mechanical performance of underground flexible structures such as buried pipes or culverts made of plastics depend not only on the properties of the structure, but also the material surrounding it. Flexible drains can deflect by 30% with the joints staying tight, or even invert. Large deformations of the structure are difficult to model in the framework of Finite Element Method, but straightforward in Discrete Element Methods....
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Determination of the minimal critical rotational speeds of the circular saw blades with the quasi-twin resonant frequencies
PublikacjaTo determine the minimal critical rotational speeds of the circular saw blades is the fundamental aspect of obtaining the range of the rotational operating speeds, by which the circular saw blade can work with required stability. While for the circular saw blades with full-homogeneous bodies the determination of such rotational speeds is the relatively low level of difficulty function, whereas for circular saw blades with more...
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Structural factors affecting affinity of cytotoxic oxathiole-fused chalcones toward tubulin
PublikacjaSynthesis, in vitro cytotoxic activity, and interaction with tubulin of (E)-1-(6-alkoxybenzo[d][1,3]oxathiol- 5-yl)-3-phenylprop-2-en-1-one derivatives (2) are described. Some of the compounds demonstrated cytotoxic activity at submicromolar concentrations, and the activity could be related to interaction with tubulin at the colchicine binding site. Interaction of selected derivatives with tubulinwas evaluated using molecular modeling,...
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Particle Shape Effect on Macroscopic Behaviour of Underground Structures: Numerical and Experimental Study
PublikacjaAbstract: The mechanical performance of underground flexible structures such as buried pipes or culverts made of plastics depend not only on the properties of the structure, but also on the material surrounding it. Flexible drains can deflect by 30% with the joints staying tight, or even invert. Large deformations of the structure are difficult to model in the framework of Finite Element Method, but straightforward in Discrete...
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Application of vibrational spectroscopy, thermal analyses and X-Ray diffraction in the rapid evaluation of the stability in solid-state of ranitidine, famotidine and cimetidine
PublikacjaThis paper reports the study on applicability of Fourier transform infrared (FTIR), near-infrared (NIR) and Raman spectroscopy, differential scanning calorimetry (DSC) and X-ray diffraction (XRD) for the estimation of the chemical stability and photostability of histamine H2-receptor antagonist substances. Ranitidine hydrochloride (RAN), famotidine (FAM) and cimetidine (CIM) were tested and differences in sensitivity were measured...
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Effect of Porosity on the Thermo-Mechanical Behavior of Friction-Stir-Welded Spark-Plasma-Sintered Aluminum Matrix Composites with Bimodal Micro- and Nano-Sized Reinforcing Al2O3 Particles
PublikacjaThe thermo-mechanical behavior of nanosized Al2O3 particles reinforcing aluminum was analyzed in the present paper. The material was prepared by spark plasma sintering and friction stir welding. The thermal stresses affecting the composite behavior during welding were modeled through COMSOL MultiPhysics, and the results were validated by the analyses of the composites’ mechanical properties. The spark-plasma-sintered materials...
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Neural networks and deep learning
PublikacjaIn this chapter we will provide the general and fundamental background related to Neural Networks and Deep Learning techniques. Specifically, we divide the fundamentals of deep learning in three parts, the first one introduces Deep Feed Forward Networks and the main training algorithms in the context of optimization. The second part covers Convolutional Neural Networks (CNN) and discusses their main advantages and shortcomings...
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Numerical Model of the Aortic Valve Implanted Within Real Human Aorta
PublikacjaCardiovascular system diseases are the main cause of deaths in developed and developing countries. The main reasons are myocardial infarction, heart failure, stroke and valvular diseases. These are caused mainly by arteriosclerosis. The valvular diseases involve a significant burden for the health care system and their frequency is rising with the patient age. This work describes the tools and numerical models appropriate for modeling...
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CeIr3: superconductivity in a phase based on tetragonally close packed clusters
PublikacjaWe present the crystallographic analysis, superconducting and spectroscopic characterization, and theoretical modeling of CeIr3. Lattice parameters a = 5.2945(1) Å and c = 26.219(1) Å are found for the R-3m symmetry crystal structure, which are close to the literature values. CeIr3 is a moderate type-II superconductor (κ GL = 17, λ e–p = 0.65) below 2.5 K. Ce ions exhibit a strongly intermediate valence character as evidenced by...
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Feasibility Study GaN Transistors Application in the Novel Split-Coils Inductive Power Transfer System with T-Type Inverter
PublikacjaA promising solution for inductive power transfer and wireless charging is presented on the basis of a single-phase three-level T-type Neutral Point Clamped GaN-based inverter with two coupled transmitting coils. The article focuses on the feasibility study of GaN transistor application in the wireless power transfer system based on the T-type inverter on the primary side. An analysis of power losses in the main components of the...
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Detection of petroleum products using optical coherence tomography
PublikacjaIn this work, we present a novel method developed for the analysis of the properties of thin layers for detecting petroleum products on a water surface using a commercially available optical coherence tomography (OCT) system. The spectral density analysis of the signal from a spectroscopic OCT (S-OCT) enables us to perform the precision calculation of the thin layer thickness and other properties like homogeneity, and dispersion,...
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СИЛОВОЙ ПРЕОБРАЗОВАТЕЛЬ С АКТИВНЫМ ПОДАВЛЕНИЕМ ВЫСШИХ ГАРМОНИК ДЛЯ СИСТЕМ ЭЛЕКТРОСНАБЖЕНИЯ ЛЕТАТЕЛЬНЫХ АППАРАТОВ (Power converter with active suppression of higher harmonics for aircraft power supply systems)
PublikacjaПредставлены два алгоритма активной фильтрации для силового преобразователя с активным подавлением высших гармоник. Первый алгоритм основан на дискретном преобразовании Фурье: посредством синтезированной системы управления инвертированные измеренные высшие гармоники напряжения поступают на вход инвертора. Второй метод управления основан на алгоритме с использованием принципов самообучения, что значительно снижает потребность в...
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Michał Bernard Pietrzak dr hab.
OsobyMichał Bernard Pietrzak jest kierownikiem Katedry Statystyki i Ekonometrii na Wydziale Ekonomii i Zarządzania Politechniki Gdańskiej oraz zastępcą redaktora naczelnego ds. oceny pod względem poprawności statystycznej czasopism: Oeconomia Copernicana i Equilibrium. Quarterly Journal of Economics and Economic Policy. Do października 2021 pracował na stanowisku profesora nadzwyczajnego na Wydziale Nauk Ekonomicznych i Zarządzania,...
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Muhammad Jamshed Abbass Phd in Electrical Engineering
OsobyMuhammad Jamshed Abbass received the M.S. degree in electrical engineering from Riphah International University, Islamabad. He is currently pursuing the Ph.D. degree with the Wrocław University of Science and Technology, Wroclaw, Poland. His research interests include machine learning, voltage stability within power systems, control design, analysis, the modeling of electrical power systems, the integration of numerous decentralized...
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Abdalraheem Ijjeh Ph.D. Eng.
OsobyThe primary research areas of interest are artificial intelligence (AI), machine learning, deep learning, and computer vision, as well as modeling physical phenomena (i.e., guided waves in composite laminates). The research interests described above are utilized for SHM and NDE applications, namely damage detection and localization in composite materials.
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On deterministic procedures for low-cost multi-objective design optimization of miniaturized impedance matching transformers
PublikacjaPurpose This paper aims to investigate deterministic strategies for low-cost multi-objective design optimization of compact microwave structures, specifically, impedance matching transformers. The considered methods involve surrogate modeling techniques and variable-fidelity electromagnetic (EM) simulations. In contrary to majority of conventional approaches, they do not rely on population-based metaheuristics, which permit lowering...
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A Perspective on Fast-SPICE Simulation Technology
PublikacjaThis chapter presents an introduction to the area of accelerated transistor-level (‘fast-SPICE’) simulation for automated verification and characterization of integrated circuits (ICs) from technologist’s perspective. It starts with outlining goals, expectations and typical usage models for fast-SPICE simulators, stressing how they differ from regular SPICE tools. It continues with presenting and classifying core technologies typically...
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Improvement of Task Management with Process Models in Small and Medium Software Companies
PublikacjaSmall and medium software companies exhibit many special features that give reason for a dedicated approach to process improvement. They often cannot afford implementing maturity models or quality standards both in terms of time and money. Instead, they expect simpler solutions that can allow to run projects in more systematic and repeatable way, increase quality and knowledge management. In this paper, we present a method focused...
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A New Fuzzy Sliding Mode Controller with PID Sliding Surface for Underwater Manipulators
PublikacjaDesign of an accurate and robust controller is challenging topic in underwater manipulator control. This is due to hydrodynamic disturbances in underwater environment. In this paper a sliding mode control (SMC) included a PID sliding surface and fuzzy tunable gain is designed. In this proposed controller robustness property of SMC and fast response of PID are incorporated with fuzzy rules to reduce error tracking. In the control...
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Efficient Multi-Objective Simulation-Driven Antenna Design Using Co-Kriging
PublikacjaA methodology for fast multi-objective antenna optimization is presented. Our approach is based on response surface approximation (RSA) modeling and variable-fidelity electromagnetic (EM) simulations. In the design process, a computationally cheap RSA surrogate model constructed from sampled coarse-discretization EM antenna simulations is optimized using a multi-objective evolutionary algorithm. The initially determined Pareto...
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Model of a Maturity Capsule in Managing IT Projects
PublikacjaThe main purpose of this article is to present a report on the development of a model of information technology management (MITM). This model is an answer to the need to support decision making in the selection of methods and information technologies. This article presents a multisequential model (MSM) of technology selection and a model for initial processing procedures (IPP) necessary for the MITM model. The presentation of the...
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Sounding of Layered Marine Bottom - Model Investigations
PublikacjaThe necessary actions connected with interpretations of examining of physical properties of sea bottom structure is developing of proper procedure of modeling of the layered structure. The implementation of the acoustic waves for the determination of seabed stratification requires a precise diagnosis of the topic from both the theoretical and practical side. Little differences between the parameters of sediments, as well as irregular...
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Distributed protection against non-cooperative node behavior in multi-hop wireless networks
PublikacjaAn important security problem in today's distributed data networks is the prevention of non-cooperative behavior i.e., attacks consisting in the modification of standard node operation to gain unfair advantage over other system nodes. Such a behavior is currently feasible in many types of computer networks whose communication protocols are designed to maximize the network performance assuming full node cooperation. Moreover, it...
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The Indication Methods and Techniques of Urban Light Pollution
PublikacjaThe goal of this study is to review and categorize approaches and methods of facing urban light pollution. Probing various references and documents, the current practice focus on extracting and reviewing different types of urban light pollution detection, survey, and measurement to define a taxonomy of methods by instant comparison. The means of measurement and detecting this pollution include 14 most cited techniques that have...
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CFD-based evaluation of current-carrying capacity of power cables installed in free air
PublikacjaEvaluation of current-carrying capacity of power cables and selection of cross-sectional area of their conductors are mainly performed in accordance with requirements of EN, IEC or IEEE standards. However, these standards do not provide all methods of cables installation and location which occur in practice. Thus, in some cases, performance of advanced modeling of various thermal phenomena, affecting power cables current-carrying...
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On-line Search in Two-Dimensional Environment
PublikacjaWe consider the following on-line pursuit-evasion problem. A team of mobile agents called searchers starts at an arbitrary node of an unknown network. Their goal is to execute a search strategy that guarantees capturing a fast and invisible intruder regardless of its movements using as few searchers as possible. As a way of modeling two-dimensional shapes, we restrict our attention to networks that are embedded into partial grids:...
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Enhancement of fiber-optic low-coherence Fabry-Pérot interferometer with ZnO ALD films
PublikacjaIn this paper investigation of the enhanced fiber-optic low coherence Fabry-Pérot interferometer with zinc oxide (ZnO) film deposited by atomic layer deposition (ALD) was presented. Model of the interferometer, which was constructed of single-mode optical fiber with applied ZnO ALD films, was built. The interferometer was also examined by means of experiment. Measurements were performed for both reflective and transmission modes,...
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Performance of Noise Map Service Working in Cloud Computing Environment
PublikacjaIn the paper a noise map service designated for the user interested in environmental noise subject is presented. It is based on cloud computing. Noise prediction algorithm and source model, developed for creating acoustic maps, are working in cloud computing environment. In the study issues related to noise modeling of sound propagation in urban spaces are discussed with a special focus on road noise. Examples of results obtained...
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Proceedings of the 9th International Conference on Structural Dynamics, EURODYN 2014
PublikacjaSince offshore wind turbine supporting structures are subjected to dynamic environments with time-varying loading conditions, it is important to model their dynamic behavior and validate these models by means of vibrational experiments. In this paper assessment of dynamical state of the structure is investigated by means of both: numerical modeling, and experimental modal analysis. In experimental modal analysis, capturing the...
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Inverse surrogate models for fast geometry scaling of miniaturized dual-band couplers
PublikacjaRe-design of microwave structures for various sets of performance specifications is a challenging task, particularly for compact components where considerable electromagnetic (EM) cross-couplings make the relationships between geometry parameters and the structure responses complex. Here, we address geometry scaling of miniaturized dual-band couplers by means of inverse surrogate modeling. Our approach allows for fast estimation...
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High Efficiency Dual-Active-Bridge Converter with Triple-Phase-Shift Control for Battery Charger of Electric Vehicles
PublikacjaAn optimal modulation scheme with triple-phase-shift (TPS) control could increase the efficiency in the entire load range for a dual-active-bridge (DAB) converter under wide output voltage range conditions. Therefore, this study proposes a convergent approach to TPS mode selection, coupled with an optimal modulation scheme, ensuring the circuit’s efficiency over the entire range in the realm of a high-power and high-efficiency...
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Qualia: About Personal Emotions Representing Temporal Form of Impressions - Implementation Hypothesis and Application Example
PublikacjaThe aim of this article is to present the new extension of the xEmotion system as a computerized emotional system, part of an Intelligent System of Decision making (ISD) that combines the theories of affective psychology and philosophy of mind. At the same time, the authors try to find a practical impulse or evidence for a general reflection on the treatment of emotions as transitional states, which at some point may lead to the...
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Toward Human Chromosome Knowledge Engine
PublikacjaHuman chromosomes carry genetic information about our life. Chromosome classification is crucial for karyotype analysis. Existing chromosome classification methods do not take into account reasoning, such as: analyzing the relationship between variables, modeling uncertainty, and performing causal reasoning. In this paper, we introduce a knowledge engine for reasoning-based human chromosome classification that stores knowledge...
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Optimization of Bread Production Using Neuro-Fuzzy Modelling
PublikacjaAutomation of food production is an actively researched domain. One of the areas, where automation is still not progressing significantly is bread making. The process still relies on expert knowledge regarding how to react to procedure changes depending on environmental conditions, quality of the ingredients, etc. In this paper, we propose an ANFIS-based model for changing the mixer speed during the kneading process. Although the...
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Market orientation and hotel performance: The mediating effect of creative marketing programs
PublikacjaThis work investigates the indirect effects between market orientation and hotel performance through creative marketing programs. The focus is on exploring the indirect effects between 1) customer orientation, competitor orientation, and cross-functional integration; and 2) hotel financial performance through two aspects of creative marketing programs, namely, novelty and meaningfulness. Through an empirical analysis using structural equation...
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Searching for Solvents with an Increased Carbon Dioxide Solubility Using Multivariate Statistics
PublikacjaIonic liquids (ILs) are used in various fields of chemistry. One of them is CO2 capture, a process that is quite well described. The solubility of CO2 in ILs can be used as a model to investigate gas absorption processes. The aim is to find the relationships between the solubility of CO2 and other variables—physicochemical properties and parameters related to greenness. In this study, 12 variables are used to describe a dataset...
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Corporate social responsibility practices incomes and outcomes: Stakeholders' pressure, culture, employee commitment, corporate reputation, and brand performance. A Polish–German cross‐country study
PublikacjaThis study aims to compare employee perception of corporate social responsibility (CSR) practice incomes and outcomes in the construction industry in Poland and Germany. It proposes a model that examines the influence of stakeholder pressure, culture, and CSR practices on company brand performance, reputation, and employee identification. The findings suggest that the structure of relationships varies for project‐managed construction...
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Computationally Effcient Solution of a 2D Diffusive Wave Equation Used for Flood Inundation Problems
PublikacjaThis paper presents a study dealing with increasing the computational efficiency in modeling floodplain inundation using a two-dimensional diffusive wave equation. To this end, the domain decomposition technique was used. The resulting one-dimensional diffusion equations were approximated in space with the modified finite element scheme, whereas time integration was carried out using the implicit two-level scheme. The proposed...