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Pomiędzy kontrolą i zaufaniem – jakich liderów potrzebują wirtualne zespoły projektowe
PublikacjaArtykuł dotyczy zarządzania zespołem wirtualnym, które jest szczególnym wyzwaniem ze względu na rozproszenie geograficzne członków zespołu oraz porozumiewanie się za pośrednictwem technologii informacyjnej. Skoncentrowano się na utrzymywaniu odpowiedniej proporcji pomiędzy zaufaniem i kontrolą zespołu i opracowano listę rekomendacji dla liderów zespołów wirtualnych, dotyczących budowania zaufania i koordynacji pracy. Do realizacji...
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Intelligent Knowledge-Base Model for IT Support Organization Evolution
PublikacjaThe goal of the paper is building the knowledge-based model for predicting the state of the IT support organization. These organizations, critical for development of various business sectors, are facing the problem of their transformation. It is the result of the fundamental change in the role of the IT organizations in the current economy. The complexity of the processes, the difficulty adjusting the operations and limited ability...
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Nested Kriging with Variable Domain Thickness for Rapid Surrogate Modeling and Design Optimization of Antennas
PublikacjaDesign of modern antennas faces numerous difficulties, partially rooted in stringent specifications imposed on both electrical and field characteristics, demands concerning various functionalities (circular polarization, pattern diversity, band-notch operation), but also constraints imposed upon the physical size of the radiators. Conducting the design process at the level of full-wave electromagnetic (EM) simulations, otherwise...
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GIS-based hydrodynamic modeling for urban flood mitigation in fast-growing regions: a case study of Erbil, Kurdistan Region of Iraq
PublikacjaFloods 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...
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The congruence of mental models in entrepreneurial teams – implications for performance and satisfaction in teams operating in an emerging economy
PublikacjaPurpose – The paper aims to explore the relationship between the congruence of mental models held by the members of entrepreneurial teams operating in an emerging economy (Poland) and entrepreneurial outcomes (performance and satisfaction). Design/methodology/approach – The data obtained from 18 nascent and 20 established entrepreneurial teams was analysed to answer hypotheses. The research was quantitative and was conducted using...
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Enhancing Resilience of FSO Networks to Adverse Weather Conditions
PublikacjaOptical wireless networks realized by means of gigabit optical wireless communication (OWC) systems are becoming, in a variety of applications, an important alternative, or a complementary solution, to their fiber-based counterparts. However, performance of the OWC systems can be considerably degraded in periods of unfavorable weather conditions, such as heavy fog, which temporarily reduce the effective capacity of the network....
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Mathematical Modeling of Ice Dynamics as a Decision Support Tool in River Engineering
PublikacjaThe prediction of winter flooding is a complicated task since it is affected by many meteorological and hydraulic factors. Typically, information on river ice conditions is based on historical observations, which are usually incomplete. Recently, data have been supplemented by information extracted from satellite images. All the above mentioned factors provide a good background of the characteristics of ice processes, but are not...
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Optimizing CO2 Purification in a Negative CO2 Emission Power Plant
PublikacjaIn the pursuit of mitigating CO2 emissions, this study investigates the optimisation of CO2 purification within a Negative CO2 Emission Power Plant using a spray ejector condenser (SEC) coupled with a separator. The approach involves direct-contact condensation of vapour, primarily composed of an inert gas (CO2), facilitated by a subcooled liquid spray. A comprehensive analysis is presented, employing a numerical model to simulate...
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Analiza drgań przewodu jezdnego sieci trakcyjnej w aspekcie oceny jej stanu technicznego.
PublikacjaGórna sieć trakcyjna jest nadal najefektywniejszym sposobem zasilania kolejowych pojazdów elektrycznych. Sieć jezdna nie ma możliwości technicznych redundancji, co wymaga okresowej oceny stanu technicznego w celu zapewnienia prawidłowej współpracy z odbierakami prądu pojazdów. W artykule przedstawiono aspekty oceny stanu technicznego górnej sieci trakcyjnej na podstawie modelowania matematycznego i wybranych badań laboratoryjnych....
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Zespół wypalenia zawodowego i zmęczenie w kontekście pracy zmianowej i stresu zawodowego wśród pielęgniarek chirurgicznych
PublikacjaTwo aspects of work-related consequences among surgery nurses are discussed: burnout syndrome and fatigue, having an impact on the quality of medical care and safety of patients. Siegrist's effort-reward imbalance model has been adopted as a concept of occupational stress. The organization of working time, i.e. the length of shifts and their rotation, was considered. Nurses on twelve-hour shifts worked much harder, were more tired...
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Dwukierunkowy przekształtnik 4L-DC z aktywną regulacją napięć w obwodzie pośredniczącym
PublikacjaW artykule opisano model laboratoryjny i wyniki badań dwukierunkowego symetrycznego (ang. Back-to-Back) przekształtnika 4L-DC (ang. Four Level Diode Clamped) z dwukierunkowym dwustopniowym przetwarzaniem energii (połączenie typu ang. Back-To-Back). W celu równoważenia i regulacji napięć kondensatorów w obwodzie pośredniczącym układu zastosowano dwa trójpoziomowe przerywacze DC-DC sterowane synchronicznie metodą modulacji PO-PWM...
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Energy recovery effectiveness in trolleybus transport
PublikacjaNowadays the issue of electric energy saving in public transport is becoming a key area of interest whichis connected both with a growth in environmental awareness of the society and an increase in the pricesof fuel and electricity. One of the possibilities to reduce energy consumption in urban public transport isto increase the extent of regenerative braking energy utilization. This can be achieved by its accumulationin the supercapacitors...
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SONIC - Self-optimizing narrowband interference canceler: comparison of two frequency tracking strategies
PublikacjaThis paper presents a new approach to rejection of complex-valued sinusoidal disturbances acting at the output of a discrete-time linear stable plant with unknown and possibly time-varying dynamics. It is assumed that both the instantaneous frequency of the sinusoidal disturbance and its amplitude may be slowly varying with time and that the output signal is contaminated with wideband measurement noise. The proposed disturbance...
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Investigation of the road noise source employing an automatic noise monitoring station
PublikacjaThe paper presents a pilot investigation of noise source models in two selected localizations in the context of future dynamic noise map creation. The experiments were carried out using the automatic noise monitoring station engineered at the Multimedia Systems Departmentof the Gda´nsk University of Technology. The results of the noise measurements employing monitoring stations and its comparison to the reference values are depicted....
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Simulation Model for Application of the SDN Concept in IMS/NGN Network Transport Stratum
PublikacjaThe paper presents a simulation model allowing examination of cooperation between two currently used telecommunication networks concepts: IP Multimedia Subsystem/Next Generation Network (IMS/NGN) and Software-Defined Networking (SDN). Application of the SDN architecture elements in IMS/NGN networks will enable unified control and management of transport resources for various transport technologies and equipment manufacturers. However,...
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Free volume in physical absorption of carbon dioxide in ionic liquids: Molecular dynamics supported modeling
PublikacjaUnderstanding 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...
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The dynamics of the total output of the fishery sector: The case of Indonesia
PublikacjaThe purpose of this study is to analyze the dynamics of the total output of the Indonesian fishery industry when the changes of the final demand occur. This study employs a demand-pull Input-Output (IO) quantity model, one of the calculation tools in the IO analysis, as an analysis instrument. Two conditions are noticed in calculation and analysis parts, namely (1) “whole sector change”, and (2) “pure change”. An initial period...
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The dynamics of the total output of the Japanese fisheries sector: An analysis using input-output approach
PublikacjaThe purpose of this study is to investigate the dynamics of the total output of the fisheries industry when the changes of the final demand occur. This study focuses on the case of Japan. This study employs a demand-pull Input-Output (IO) quantity model, one of the calculation instruments in the IO analysis, as an analysis tool. Two conditions are included in calculation and analysis parts, namely (1) “whole sector change”, and...
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Cost-efficient simulation-driven design of compact impedance matching transformers
PublikacjaIn this paper, an algorithmic framework for cost-efficient design optimization of miniaturized impedance matching transformers has been presented. Our approach exploits a bottom-up design that involves translating the overall design specifications for the circuit at hand to its elementary building blocks (here, compact microstrip resonant cells, CMRCs), as well as fast surrogate-assisted optimization of the cells followed by simulation-based...
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Fast simulation-driven design optimization of UWB band-notch antennas
PublikacjaIn this letter, a simple yet reliable and automated methodology for rapid design optimization of ultra-wideband (UWB) band-notch antennas is presented. Our approach is a two-stage procedure with the first stage focused on the design of the antenna itself, and the secondstage aiming at identification of the appropriate dimensions of the resonator with the purpose of allocating the band-notch in the desired frequency range. For the...
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Multi-objective antenna design by means of sequential domain patching
PublikacjaA simple yet robust methodology for rapid multiobjective design optimization of antenna structures has been presented. The key component of our approach is sequential domain patching of the design space which is a stencil-based search that aims at creating a path that connects the extreme Pareto-optimal designs, obtained by means of single-objective optimization runs. The patching process yields the initial approximation of the...
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The impacts of final demands changes on the total outputs of Japanese industrial sectors: A further study
PublikacjaThe purpose of the current study is to expand the previous studies which analyze the impacts of final demands changes on the total outputs of industrial sectors of a specific country. More specifically, the study conducts the analysis regarding the impacts on the total outputs of Japanese industries. The study employs a demand-pull Input-Output (IO) quantity model, one of the calculation tools in the IO analysis. The study focuses...
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Reactions of lithiated diphosphanes R2P-P(SiMe3)LiTHF (R = tBu, iPr) with [(PNP)TiCl2]. Two different coordination types of phosphanylphosphido ligand to the metal center.
Publikacja[(PNP)TiCl2] (PNP = N[2-PiPr2-4-methylphenyl]2) reacts with one equivalent of lithium derivative of diphosphane R2P-P(SiMe3)LinTHF (R = tBu, iPr) in toluene and forms the first complex with g1-coordination [(PNP)Ti(Cl){g1-P(SiMe3)-PtBu2}] (1) and complex with g2-coordination [(PNP)Ti(Cl){g2-P(SiMe3)-PiPr2}] (2) of phosphanylphosphido ligands to the titanium center. The similar reaction with two equivalents of tBu2P-P(SiMe3)LinTHF...
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The impacts of final demands changes on the total outputs of Japanese industrial sectors: A further study
PublikacjaThe purpose of the current study is to expand the previous studies which analyze the impacts of final demands changes on the total outputs of industrial sectors of a specific country. More specifically, the study conducts the analysis regarding the impacts on the total outputs of Japanese industries. The study employs a demand-pull Input-Output (IO) quantity model, one of the calculation tools in the IO analysis. The study focuses...
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Global sensitivity analysis of membrane model of abdominal wall with surgical mesh
PublikacjaThe paper addresses the issue of ventral hernia repair. Finite Element simulations can be helpful in the optimization of hernia parameters. A membrane abdominal wall model is proposed in two variants: a healthy one and including hernia defect repaired by implant. The models include many uncertainties, e.g. due to variability of abdominal wall, intraabdominal pressure value etc. Measuring mechanical properties with high accuracy...
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A DISCRETE-CONTINUOUS METHOD OF MECHANICAL SYSTEM MODELLING
PublikacjaThe paper describes a discrete-continuous method of dynamic system modelling. The presented approach is hybrid in its nature, as it combines the advantages of spatial discretization methods with those of continuous system modelling methods. In the proposed method, a three-dimensional system is discretised in two directions only, with the third direction remaining continuous. The thus obtained discrete-continuous model is described...
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ARRAY OF MINIJETS – THERMAL AND HYDRAULIC PHENOMENA IN BOUNDARY LAYER
PublikacjaPresented work considers flow and thermal phenomena occurring in the system consisting of minijets array and heated with constant heat flux surface. Numerical analyses, based on the mass, momentum and energy conservation laws, were conducted. Focus was placed on the proper model construction, in which turbulence and boundary layer modelling was crucial. Calculations were done for various mass flow rates. The main calculations were...
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Znaczenie płci w procesie zakupu marek własnych sieci handlowych – analiza wielogrupowa
PublikacjaThe purpose of the article is to analyze the differences in the behavior of men and women in the process of purchasing store brands (SBs). Using an established conceptual model, we intended to identify differences, depending on gender of buyers, in the size of the effects of store image and brand price-image on perceived risk and subsequently on store brand purchase intention. A total of 652 respondents participated in the study....
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Modular power converter topologies for energy storage and electric power distribution systems
PublikacjaThis paper describes selected issues concerning realization of energy storage system (ESS) designed to operate in power distribution system. In order to achieve scalability of the system a modular approach is proposed. In addition to this different configuration of the system are analyzed, where depending on requirements and application a scalability in power, in energy capacity of energy storage resource and both in power and...
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Comparison of the exponential thermal transient parameterization methods with the SMTP method in the unipedicled DIEP flap computer modelling and simulation
PublikacjaThe aim of this paper is to compare the spatial contrast of the image descriptors obtained via three different thermal transient parameterization methods in Active Dynamic Thermography. The thermal constants and amplitude values of the one- and two- exponential parametrization are compared to the Simplified Magnitude-Temporal Parametrization method (SMTP). The comparison is performed using the data obtained by simulating the cold...
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Reduced-cost constrained miniaturization of wideband antennas using improved trust-region gradient search with repair step
PublikacjaIn the letter, an improved algorithm for electromagnetic (EM)-driven size reduction of wideband antennas is proposed. Our methodology utilizes variable-fidelity EM simulation models, auxiliary polynomial regression surrogates, as well as multi-point response correction. The constraint handling is implicit, using penalty functions. The core optimization algorithm is a trust-region gradient search with a repair step added in order...
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Development of tools for road infrastructure safety management for the provinces (voivodeships) in Poland
PublikacjaThe development of modern tools for road infrastructure safety management will help to reduce the number of fatalities and serious injuries as one of the main objectives adopted in 2013 in the National Road Safety Programme 2014-2020 and the new Road Safety Programme 2011-2020 in the EU. Risk Management in Highway Engineering can be applied in developing tools essential in the process of safety management. Risk Management in Highway...
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Numerical modeling of exciton impact in two crystalographic phases of the organo-lead halide perovskite (CH3NH3PbI3) solar cell
PublikacjaTo improve the power conversion efficiency of solar cells based on organo–lead halide perovskites, a detailed understanding of the device physics is fundamental. Here, a computational analysis of excitons impact is reported for these types of photocell. Numerical calculations based on the model, which take into account electronic charge carriers (electrons and holes), excitons and ions, have been carried out. The role of excitons...
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Structure and computationally-efficient simulation-driven design of compact UWB monopole antenna
PublikacjaIn this letter, a structure of a small ultra-wideband (UWB) monopole antenna, its design optimization procedure as well as experimental validation are presented. According to our approach, antenna compactness is achieved by means of a meander line for current path enlargement as well as the two parameterized slits providing additional degrees of freedom that help to ensure good impedance matching. For the sake of reliability, the...
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Usability of Mobile Applications: A Consolidated Model
PublikacjaMobile devices have become an integral part of the digital ecosystem, connecting people, businesses, and information around the world in ways never before possible. In particular, smartphones, tablets and other handheld devices equipped with mobile applications have changed every aspect of our lives. Today, a user can choose from nearly five million applications available for both Android and iOS operating systems. However, only...
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Cost-Efficient Multi-Objective Design of Miniaturized Microwave Circuits Using Machine Learning and Artificial Neural Network
PublikacjaDesigning microwave components involves managing multiple objectives such as center frequencies, impedance matching, and size reduction for miniaturized structures. Traditional multi-objective optimization (MO) approaches heavily rely on computationally expensive population-based methods, especially when exe-cuted with full-wave electromagnetic (EM) analysis to guarantee reliability. This paper introduces a novel and cost-effective...
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Privacy-Preserving, Scalable Blockchain-Based Solution for Monitoring Industrial Infrastructure in the Near Real-Time
PublikacjaThis paper proposes an improved monitoring and measuring system dedicated to industrial infrastructure. Our model achieves security of data by incorporating cryptographical methods and near real-time access by the use of virtual tree structure over records. The currently available blockchain networks are not very well adapted to tasks related to the continuous monitoring of the parameters of industrial installations. In the database...
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Fracture Energy of Bonded Joints with 2D Elastic Adhesive Layer
PublikacjaWhen bonded joint is subjected to mode I fracture loading, the adhesive joints analytical solutions treats the adhesive layer, usually, as not existing or 1D Hooke elastic layer. In the case of 1D elastic layer, represented as Hookes spring element, is acting, only, in direction contrary to the applied load. Basing on the information yielded from sensitive laser profilometry technique, where deflections of bonded part of the joint...
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Problems of modelling toxic compounds emitted by a marine internal combustion engine for the evaluation of its structure parameters
PublikacjaThe paper presents the possibility of using an analytical study of the engine exhaust ignition to evaluate the technical condition of the selected components. Software tools available for the analysis of experimental data commonly use multiple regression model that allows the study of the effects and iterations between model input quantities and one output variable. The use of multi-equation models gives a lot of freedom in the...
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Evaluation of the factors influencing business bankruptcy risk in Poland
PublikacjaThis article is devoted to the issue of assessing the causes of business failure. The presented studies answer two research questions – what are the causes of corporate bankruptcies in Poland and how to more efectively predict the scale of bankruptcies in the country. The author has conducted a study to analyze the specic endogenous and exogenous causes of company bankruptcy depending on the type of the bankruptcy with consideration...
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An energetic analysis of a gas turbine with regenerative heating using turbine extraction at intermediate pressure - Brayton cycle advanced according to Szewalski's idea
PublikacjaIn this paper, a modification of a simple gas turbine into the Brayton cycle with regenerative heating, using turbine extraction at intermediate pressure, is presented. The main concept of the retrofitting is based on the transfer of heat from the turbine exhaust gases to the air entering the combustion chamber. The extracted gas transfers heat to air via the divided regenerative heat exchanger and after that is compressed and...
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Development of Gas Sensor Array for Methane Reforming Process Monitoring
PublikacjaThe article presents a new method of monitoring and assessing the course of the dry methane reforming process with the use of a gas sensor array. Nine commercially available TGS chemical gas sensors were used to construct the array (seven metal oxide sensors and two electrochemical ones). Principal Component Regression (PCR) was used as a calibration method. The developed PCR models were used to determine the quantitative parameters...
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Liniowe i nieliniowe modele wielowymiarowej kalibracji do predykcji stężenia substancji z pomiarów woltamperometrycznych
PublikacjaPomiary woltamperometryczne znajdują zastosowanie w wielu dziedzinach nauki i techniki, np. w przemyśle farmaceutycznym. Dane uzyskane w wyniku takich pomiarów zawierają informację odnośnie rodzaju i stężenia badanej substancji, jednakże są one często kłopotliwe w bezpośredniej interpretacji. Z tego powodu, istnieje konieczność wykorzystania odpowiednich metod matematycznych, które umożliwiają uzyskanie bezpośredniej i precyzyjnej...
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Using water sources extent during inundation as a reliable predictor for vegetation zonation in a natural wetland floodplain
PublikacjaDistinctive zones of inundation water during floods were shown to originate from different sources in some major floodplains around the world. Recent research showed that the zonation of water in rivers and floodplains is related to vegetation patterns. In spite of this, water source zones were not used for vegetation modeling due to difficulties in their delineation. In this study, we used simulation results of a fully-coupled...
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Fast Design Closure of Compact Microwave Components by Means of Feature-Based Metamodels
PublikacjaPrecise tuning of geometry parameters is an important consideration in the design of modern microwave passive components. It is mandatory due to limitations of theoretical design methods unable to quantify certain phenomena that are important for the operation and performance of the devices (e.g., strong cross-coupling effects in miniaturized layouts). Consequently, the initial designs obtained using analytical or equivalent network...
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Zero-range potentials for Dirac particles: Bound-state problems
PublikacjaA model in which a massive Dirac particle in $\mathbb{R}^{3}$ is bound by $N\geqslant1$ spatially distributed zero-range potentials is presented. Interactions between the particle and the potentials are modeled by subjecting a particle's bispinor wave function to certain limiting conditions at the potential centers. Each of these conditions is parametrized by a $2\times2$ Hermitian matrix (or, equivalently, a real scalar and a...
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Diaryl Sulfide Derivatives as Potential Iron Corrosion Inhibitors: A Computational Study
PublikacjaThe present work aimed to assess six diaryl sulfide derivatives as potential corrosion inhibitors. These derivatives were compared with dapsone (4,4′-diaminodiphenyl sulfone), a common leprosy antibiotic that has been shown to resist the corrosion of mild steel in acidic media with a corrosion efficiency exceeding 90%. Since all the studied compounds possess a common molecular backbone (diphenyl sulfide), dapsone was taken as the...
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Effect of free water on the quasi‑static compression behavior of partially‑saturated concrete with a fully coupled DEM/CFD approach.
PublikacjaThe work aims to numerically investigate the quasi-static response of partially fluid-saturated concrete under two-dimensional uniaxial compression at the mesoscale. We investigated how the impact of free pore fluid content (water and gas) affected the quasi-static strength of concrete. The totally and partially fluid-saturated concrete behavior was simulated using an improved pore-scale hydro-mechanical model based on DEM/CFD....
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ANALYSIS OF THE IMPACT OF THE PLANNED SEWAGE DISCHARGE FROM THE ‘NORTH’ POWER PLANT ON THE VISTULA WATER QUALITY
PublikacjaThe paper presents results of analysis of the industrial sewage discharge impact from the ‘North’ Power Plant on the Vistula water quality around 45+330 of the river kilometer. For the analysis, the two-dimensional models of flow, impurities and temperature transport were used. Hydrological conditions of the analyzed section of the river, characteristic flows and bathymetry of the riverbed in the first instance were defined....
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Mechanics of mesh implanted into abdominal wall under repetitive load. Experimental and numerical study
PublikacjaThere are a number of papers discussing medical and mechanical aspects of ventral hernia management. Despite intensive work on the problem understanding, recurrences of the sickness still happen too often. For that reason new aspects of the problem must be considered. In this paper, a change in the abdominal implant’s stiffness is discussed, which is caused by cyclic loading. Such loading influence abdominal implant e.g. while...