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Wyniki wyszukiwania dla: MATERIAL AND ENERGY FLOW ANALYSIS
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Stability and limit load analysis of a cold-formed channel section column
PublikacjaThe paper presents stability and limit load analysis of a steel column 1440 mm high of a cold-formed channel section, subjected to a combination of compression and bending. Experimental results were compared to the resistance of a code procedure and to the outcome of numerical non-linear analysis. Comparison was made of numerical solutions by means of static (Riks) and dynamic (Explicit and Implicit) methods. Perfectly elastic...
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Quantitative assessment of the influence of tensile softening of concrete in beams under bending by numerical simulations with XFEM and cohesive cracks
PublikacjaResults of the numerical simulations of the size effect phenomenon for concrete in comparison with experimental data are presented. In-plane geometrically similar notched and unnotched beams under three-point bending are analyzed. EXtended Finite Element Method (XFEM) with a cohesive softening law is used. Comprehensive parametric study with the respect to the tensile strength and the initial fracture energy is performed. Sensitivity...
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Experimental study on polymer mass used to repair damaged structures
PublikacjaA new method of repairing damaged structures by injecting the cracks with specially designed polymer mass (flexible two-component grout based on polyurethane resin) has been recently proposed. The technique is mainly dedicated to damaged masonries, especially historical structures where minimum intervention is permitted. The cracks are filled with the special injection, forming the flexible joints bonding the disrupted structural...
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Ongoing Progress on Pervaporation Membranes for Ethanol Separation
PublikacjaEthanol, a versatile chemical extensively employed in several fields, including fuel production, food and beverage, pharmaceutical and healthcare industries, and chemical manufacturing, continues to witness expanding applications. Consequently, there is an ongoing need for cost-effective and environmentally friendly purification technologies for this organic compound in both diluted (ethanol-water–) and concentrated solutions (water-ethanol–)....
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Dynamic state assessment of the water turbine with the power of 600 kW
PublikacjaThe article discusses the results of experimental studies to assess the dynamic state of the turbine set with the Kaplan turbine. The dynamic assessment was made on the basis of appropriate standards, based on the measurement results of selected parameters of vibration, which have been measured for several states of the machine load. In addition, we attempted to identify the causes of the increased vibration levels based on the...
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PROCESSING, MECHANICAL AND THERMAL PROPERTIES OF RECYCLED LOW-DENSITY POLYETHYLENE STREAMS
PublikacjaThe recycling of plastics is currently one of the most significant industrial challenges. Due to the enormous amounts of plastic wastes generated by various industry branches, it is essential to look for the potential methods of their utilization. Nevertheless, for the efficient application of recycled materials it is crucial to analyze their performance. Therefore, in presented paper we investigated the processing (melt flow index),...
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Dynamic effect of the vehicle passing under lightweight footbridge.
PublikacjaThe paper describes a numerical study of dynamic response of cable-stayed steel footbridge for a big lorry passing underneath. The footbridge is an existing object crossing Wolska street in Warsaw. The structural model of footbridge was verified by dynamic test loading. A numerical study of a vehicle passing under footbridge is presented. 2D and 3D incompressible flow fields are modeled using sliding mesh in transient CFD computation....
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System for tracking multiple trains on a test railway track
PublikacjaSeveral problems may arise when multiple trains are to be tracked using two IP camera streams. In this work, real-life conditions are simulated using a railway track model based on the Pomeranian Metropolitan Railway (PKM). Application of automatic clustering of optical flow is investigated. A complete tracking solution is developed using background subtraction, blob analysis, Kalman filtering, and a Hungarian algorithm. In total,...
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System for tracking multiple trains on a test railway track
PublikacjaSeveral problems may arise when multiple trains are to be tracked using two IP camera streams. In this work, real-life conditions are simulated using a railway track model based on the Pomeranian Metropolitan Railway (PKM). Application of automatic clustering of optical flow is investigated. A complete tracking solution is developed using background subtraction, blob analysis, Kalman filtering, and a Hungarian algorithm. In total,...
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The smartest location for an eco-district– investigation of urban spatial energy efficiency
Publikacjancreasing awareness concerning environmental aspects of spatial and architectural planning led to more deliberated projects of eco-districts. Located all over the world and constantly being improved, apart from excellent energetical parameters, most of them have one specific characteristic in common, which is location in the outskirts. The aim of this article was to understand the importance of ecological district location depending...
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Influence of service ageing on polyester-reinforced polyvinyl chloride-coated fabrics reported through mathematical material models
PublikacjaIn this paper the coupled service (constructional tension) and environmental (sunlight, rainfalls, temperature variations) ageing influence on the polyester-reinforced polyvinyl chloride (PVC)-coated fabric VALMEX is studied. Two cases of the same fabric have been analyzed: one USED for 20 years on the real construction of the Forest Opera in Sopot (Poland), and one kept as a spare material (NOT USED). The following tests have...
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New Polymeric Materials for Solid Phase Extraction
PublikacjaSolid phase extraction (SPE) is a popular sample preparation technique, which can be applied directly in gas–solid phase and liquid–solid phase, or indirectly to solid samples by using, e.g., thermodesorption with subsequent chromatographic analysis. Although SPE can be described as a physical extraction process involving a liquid phase and a solid phase, the increased use of packed sorbent formats seems to have led to a bias toward...
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Synthesis and characterization of novel renewable polyesters based on 2,5-furandicarboxylic acid and 2,3-butanediol
PublikacjaNovel polyesters from 2,5-furandicarboxylic acid or 2,5-dimethyl-furandicarboxylate and 2,3-butanediol have been synthesized via bulk polycondensation catalyzed by titanium (IV) n-butoxide, tin (IV) ethylhexanoate, or zirconium (IV) butoxide. The polymers were analyzed by size exclusion chromatography, nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy (FTIR), matrix-assisted laser ionization-desorption...
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Assessment of the usefulness of bacterial cellulose produced by Gluconacetobacter xylinus E25 as a new biological implant
PublikacjaBionanocellulose (BNC) is a clear polymer produced by the bacterium Gluconacetobacter xylinus. In our current study, “Research on the use of bacterial nanocellulose (BNC) in regenerative medicine as a function of the biological implants in cardiac and vascular surgery”, we carried out material analysis, biochemical analysis, in vitro tests and in vivo animal model testing. In stage 1 of the project, we carried out physical and...
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Comparative study of operation of condensing and traditional boilers equipped with the ORC module for electricity generation
PublikacjaCondensing technology applied to boilers is to make full use of thermal energy contained in the fuel. That means that additionaly the heat from condensation of exhaust gases can be used for the purposes of heating the domestic hot water and to cover the demand for central heating. The study analyzed the operation of the "traditional" boiler equipped with the ORC module as the similar arrangement but with the condensing boiler....
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Wykorzystanie tomografii komputerowej przy analizie jakości zacementowania - migracja gazu
PublikacjaArtykuł przedstawia opis zjawiska znanego w wiertnictwie otworowym jako migracja gazu. Opisano główne przyczyny powstawania tego negatywnego zjawiska polegającego na przepływie gazów a także płynów w zaczynie cementacyjnym lub kamieniu cementowym. Przygotowano próbki imitujące zacementowany odcinek rur okładzinowych. Skupiono się na wykorzystaniu tomografii komputerowej, oraz analizie zrekonstruowanego trójwymiarowego obrazu, w...
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Hydropower potential of the lower Vistula
PublikacjaThis paper presents an estimate analysis of the hydropower potential of the lower Vistula River from Warsaw to Gdańsk Bay. The calculations were made for a hydraulic model of the lower Vistula which takes into account potential development of barrages in a cascade system. Results obtained from the model simulations and from hydrological calculations were used to estimate the power of hydropower plants and the average annual energy...
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Rapid development of the photoresponse and oxygen evolution of TiO2 nanotubes sputtered with Cr thin films realized via laser annealing
PublikacjaRecently, earth abundant transition metal oxides have gained particular attention as potential catalyst candidates due to their availability and low-cost comparing to substrates containing precious Pt or Au species. Herein, we present characterization of morphology, structure and electrochemical properties of pulsed 532 nm laser treated TiO2 nanotubes (NT) sputtered by the thin film of chromium. Scanning electron microscopy enables...
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Post-Pyrolytic Carbon as a Phase Change Materials (PCMs) Carrier for Application in Building Materials
PublikacjaThis article covers new application for char as a carrier of phase-change materials (PCM) that could be used as an additive to building materials. Being composed of bio-char and PCM, the granulate successfully competes with more expensive commercial materials of this type, such as Micronal® PCM. As a PCM carrier, char that was obtained from the pyrolysis of chestnut fruit (Aesculus hippocastanum) with different absorbances of the...
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The adiabatic potentials of low-lying electronic states of the NaRb molecule
PublikacjaAdiabatic potential energy curves and spectroscopic constants have been calculated for the NaRb molecule. The results of ten states of the symmetry Σ+, six states of the symmetry Π, and two states of the symmetry Δ are obtained by the nonrelativistic quantum chemical method used with pseudopotentials describing the interaction of valence electrons with atomic cores. Analysis is based on a comparison with the results of other theoretical...
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Selected aspects of the surface quality of the wooden elements after planing
PublikacjaThe quality of the surface of wooden elements, that have been planed, has got a crucial meaning in the whole production process flow, since the obtained effects affect the quality of wooden surface after painting. The emergence of defects in most cases causes need to qualify workpiece as a scrap part or additional work activity must be done. In the paper selected results of the investigation of the effect of the cutting tool wear...
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Treatment of landfill leachate in a constructed free water surface wetland system over a decade – Identification of disturbance in process behaviour and removal of eutrophying substances and organic material
PublikacjaAn 8 ha free water surface wetland system in Örebro, Sweden, which has sediment traps followed by 10 ponds for treatment of landfill leachate in the methanogenic stage, was studied from 2003 to 2012. The wetland was irregularly loaded and the leachate characteristics showed high temporal and spatial variability, so Multivariate Statistical Process Control was chosen as the diagnostic tool for detecting anomalies prior to assessing...
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The Influence of the Co-Dopant Dexamethasone Phosphate on the Electrodeposition Process and Drug-Release Properties of Polypyrrole-Salicylate on Iron
PublikacjaIn this work, the influence of incorporation of two anti-inflammatory drugs dexamethasone phosphate and sodium salicylate on the electrodeposition process of polypyrrole (PPy) film on iron has been studied. The incorporation of the agents into PPy has been carried out in a one-step electropolymerization process on oxidizable iron. The role of each drug agent during the deposition process has been discussed. The morphological and...
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Effect of Semiconductor Element Substitution on the Electric Properties of Barium Titanate Ceramics
PublikacjaThe investigated ceramics were prepared by a solid-state reaction from simple oxides and carbonates with the use of a mixed oxide method (MOM). The morphology of BaTi0.96Si0.04O3 (BTSi04) ceramics was characterised by means of a scanning electron microscopy (SEM). It was found that Si+4 ion substitution supported the grain growth process in BT-based ceramics. The EDS results confirmed the high purity and expected quantitative composition...
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Multi-objective optimization of water quality, pumps operation, and storage sizing of water distribution systems
PublikacjaA multi-objective methodology utilizing the Strength Pareto Evolutionary Algorithm (SPEA2) linked to EPANET for trading-off pumping costs, water quality, and tanks sizing of water distribution systems is developed and demonstrated. The model integrates variable speed pumps for modeling the pumps operation, two water quality objectives (one based on chlorine disinfectant concentrations and one on water age), and tanks sizing cost...
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Exergy analysis of the Szewalski cycle with a waste heat recovery system
PublikacjaThe conversion of a waste heat energy to electricity is now becoming one of the key points to improve the energy efficiency in a process engineering. However, large losses of a low-temperature thermal energy are also present in power engineering. One of such sources of waste heat in power plants are exhaust gases at the outlet of boilers. Through usage of a waste heat regeneration system it is possible to attain a heat rate of approximately...
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Chemometrics for Selection, Prediction, and Classification of Sustainable Solutions for Green Chemistry—A Review
PublikacjaIn this review, we present the applications of chemometric techniques for green and sustainable chemistry. The techniques, such as cluster analysis, principal component analysis, artificial neural networks, and multivariate ranking techniques, are applied for dealing with missing data, grouping or classification purposes, selection of green material, or processes. The areas of application are mainly finding sustainable solutions...
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Chemometrics approaches to green analytical chemistry procedure development
PublikacjaChemometric tools are widely used in analytical chemistry for the reduction of data dimensionality, grouping of variables and processing of analytical signals. They have also the potential to be applied in analytical procedure development with the aim of minimizing the procedure’s environmental impact. The design of experiment gives the possibility to obtain much better information on the system response than in case of “changing...
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The impact of internal and international migration on regional convergence in Poland
PublikacjaAccording to neoclassical theory, migration is expected to speed up the convergence process between countries (Barro, Sala-i-Martin 2004). The flow of labour from low-wage regions to high-wage regions should equalise payrolls. However, the impact of migration on convergence rates is unclear when the labour flow is heterogeneous. Moreover, the movement of labour towards wealthier areas depresses the demand for goods, services and...
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Pressure-induced flow processing behind the superior mechanical properties and heat-resistance performance of poly(butylene succinate)
PublikacjaWe propose a pressure-induced flow (PIF) processing method for the simultaneous enhancement of strength, toughness, and heat resistance of biodegradable poly(butylene succinate) (PBS). The pressure and temperature were systematically adjusted to optimize the tensile strength of PBS. Under the optimized processing conditions, the structured PBS was characterized by relatively high strength of 89.5 MPa, toughness of 21.4 kJ·m−2 ,...
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Time Delay Estimation in Two-Phase Flow Investigation Using the γ-Ray Attenuation Technique.
PublikacjaTime delay estimation is an important research question having many applications in a range of technologies. Measurement of a two-phase flow in a pipeline or an open channel using radioisotopes is an example of such application. For instance, the determination of velocity of dispersed phase in that case is based on estimation of the time delay between two stochastic signals provided by scintillation probes. The proper analysis...
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Numerical analysis of the ostiomeatal complex aeration using the CFD method
PublikacjaWe aimed to analyse ostiomeatal complex (OMC) aeration using the computational fluid dynamics (CFD) method of simulation based on human craniofacial computed tomography (CT) scans. The analysis was based on CT images of 2 patients: one with normal nose anatomy and one with nasal septal deviation (NSD). The Reynolds-Average Simulation approach and turbulence model based on linear eddy viscosity supplemented with the two-equation...
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Ultrastructural analysis of the submandibular sialoliths: Raman spectroscopy and electron back-scatter studies
PublikacjaThe aim of work was the epidemiological analysis of the occurrence of sialolithiasis of the submandibular gland in adults and the evaluation of the ultrastructure of salivary stones. The study sample consisted of 44 sialoliths. Analysis of the structure and chemical composition of sialoliths was performed using a Scanning Electron Microscope and Raman Spectroscopy. Comparing our results with the literature we can say that the epidemiology...
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Characterization of magnesium doped lanthanum orthoniobate synthesized by molten salt route
PublikacjaMolten salt synthesis method has been used to prepare the single phase magnesium doped lanthanum orthoniobate. The phase composition has been checked by X-ray diffraction method and the microstructure studies have been performed by scanning electron microscopy. The high temperature properties of the material have been investigated by thermogravimetry and electrochemical impedance spectroscopy. A dependence between sample total...
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Examining Statistical Methods in Forecasting Financial Energy of Households in Poland and Taiwan
PublikacjaThis paper examines the usefulness of statistical methods in forecasting the financial energy of households. The study’s objective is to create the innovative ratios that combine both financial and demographic information of households and implement them in the forecasting models. To conduct this objective, six forecasting models are developed using three different methods—discriminant analysis, logit analysis, and decision trees...
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Tunable emission and energy transfer of B2O3–Bi2O3–AlF3 glass system doped with Eu3+/Dy3+
PublikacjaThe structure and luminescent properties of the B2O3–Bi2O–AlF3 glass system doped with Eu3+/Dy3+ ions in different molar ratios were studied. A series of glasses were synthesized by the conventional melt quenching technique. Glass transition and crystallization temperatures were examined by Differential Thermal Analysis (DTA) measurements. The amorphous character of the prepared samples was confirmed by the X-ray diffraction (XRD)...
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Improving automatic surveillance by sound analysis
PublikacjaAn automatic surveillance system, based on event detection in the video image can be improved by implementing algorithms for audio analysis. Dangerous or illegal actions are often connected with distinctive sound events like screams or sudden bursts of energy. A method for detection and classification of alarming sound events is presented. Detection is based on the observation of sudden changes in sound level in distinctive sub-bands...
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EE-ISAC—Practical Cybersecurity Solution for the Energy Sector
PublikacjaA recent survey of cybersecurity assessment methods proposed by the scientific community revealed that their practical adoption constitutes a great challenge. Further research that aimed at identifying the reasons for that situation demonstrated that several factors influence the applicability, including the documentation level of detail, the availability of supporting tools, and the continuity of support. This paper presents the...
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CAUSALITY IN MODELS OF THERMAL PROCESSES IN SHIP ENGINE ROOMS WITH THE USE OF BOND GRAPH (BG) METHOD
PublikacjaWith a single approach to modeling elements of different physical nature, the method of Bond Graph (BG) is particularly well suited for modeling energy systems consisting of mechanical, thermal, electrical and hydraulic elements that operate in the power system engine room. The paper refers to the earlier presented new concept of thermal process modeling using the BG method. The authors own suggestions for determining causality...
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The Application of a Multi-Criteria Decision-Making for Indication of Directions of the Development of Renewable Energy Sources in the Context of Energy Policy
PublikacjaThis paper presents the application of multi-criteria decision-making (MCDM) for evaluating what technologies using renewable energy sources (RES) for electricity production have the chance to develop in Poland under the current socio-economic conditions. First, the Analytical Hierarchy Process (AHP) method was used to determine the weights of the optimization criteria. Five main criteria and 30 sub-criteria were identified. Next,...
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Potential energy curves, transition and permanent dipole moments of KRb
PublikacjaWe present extensive calculations of 48 adiabatic potential energy curves of the KRb molecule. Efforts have been focused on preparing the appropriate basis sets. Compared to previous approaches, the set of new potential energy curves is extended to higher excitations, including the single-excited K(4s2S)+Rb(5d2D) and double-excited K(4p2P)+Rb(5p2P) atomic limits. Larger distances between nuclei are also taken into account. New...
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Nanostructure of the laser-modified transition metal nanocomposites for water splitting
PublikacjaAlthough hydrogen is considered by many to be the green fuel of the future, nowadays it is primarily produced through steam reforming, which is a process far from ecological. Therefore, emphasis is being put on the development of electrodes capable of the efficient production of hydrogen and oxygen from water. To make the green alternative possible, the solution should be cost-efficient and well processable, generating less waste...
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Nonlinear FEM analysis of irregular shells composed of fiber metal laminates
PublikacjaThe paper deals with the analysis of failure initiation in shells made of Fiber Metal Laminates (FML). The elas-tic material law for orthotropic lamina is stated accounting for asymmetric in-plane stress and strain measures. The asymmetry results from the employed general nonlinear 6-field shell theory where the generalized dis-placements involve the translation and the proper rotation field. The novelty of the presented results...
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Comparative Analysis of Reactive Power Compensation Devices in a Real Electric Substation
PublikacjaA constant worldwide growing load stress over a power system compelled the practice of a reactive power injection to ensure an efficient power network. For this purpose, multiple technologies exist in the knowledge market out of which this paper emphasizes the usage of the flexible alternating current transmission system (FACTS) and presents a comparative study of the static var compensator (SVC) with the static synchronous compensator...
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Stormwater and snowmelt runoff storage control and flash flood hazard forecasting in the urbanized coastal basin.
PublikacjaCity of Gdańsk is located in a coastal region where changing climatic conditions increase the frequency of extreme weather events. Developing urbanization affects the hydrology of natural basins by simplification of the drainage system and reduction of infiltration and base flow. Consequently greater runoff rates flow into storm water collection systems, reservoirs and surrounding water bodies. Not only infrastructures of urban...
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Assessment of the ice jam potential on regulated rivers and reservoirs with the use of numerical model results
PublikacjaThis study presents an attempt at estimating the jam potential on rivers with significant anthropogenic intervention in the course or flow characteristics of the river. The DynaRiCE model was used for forecasting both the place and time of an ice jam occurrence. In this modified method, two ice parameters are subjected to analysis, namely the relative ice-to-water velocity (vi/vw),and the ice thickness to single floe thickness...
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Modeling and simulation of blood flow under the influence of radioactive materials having slip with MHD and nonlinear mixed convection
PublikacjaRadioactive materials are widely in industry, nuclear plants and medical treatments. Scientists and workers in these fields are mostly exposed to such materials, and adverse effects on blood and temperature profiles are observed. In this regard, objective of the current study is to model and simulate blood based nanofluid with three very important radioactive materials, named as Uranium dioxide (UO2), Thorium dioxide (ThO2) and...
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Formulation of Time-Fractional Electrodynamics Based on Riemann-Silberstein Vector
PublikacjaIn this paper, the formulation of time-fractional (TF) electrodynamics is derived based on the Riemann-Silberstein (RS) vector. With the use of this vector and fractional-order derivatives, one can write TF Maxwell’s equations in a compact form, which allows for modelling of energy dissipation and dynamics of electromagnetic systems with memory. Therefore, we formulate TF Maxwell’s equations using the RS vector and analyse their...
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Experimental study of the use of electric car powered with stationary solar and electrochemical batteries in Northern Poland
PublikacjaThe subject of this paper is an experimental analysis of a Nissan LEAF electric car equipped with 24 kWh battery, powered from the standalone photo-voltaic (PV) charging station in Gdańsk, Poland. The calculations of charging process efficiency and range of test drives were conducted in two extreme situations (winter and summer) of sunlight and road conditions. Experiments were performed in the Laboratory of Innovative Power Technologies...
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Fundamentals of classical and analytical mechanics
PublikacjaThe book is a monographic description of the present attempt to Newtonian and Lagrangian mechanics. But also, it could be found as a supplementary educational material useful for the graduate courses in mechanics taken by students majoring in mechanical engineering, physics or physical science. In the book you can find a brief introduction to concepts and principles of algebra of vectors; Kinematics of particles, mainly focused...