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Metody analizy energochłonności w przemyśle
PublikacjaBadania przeprowadzone w rozprawie doktorskiej pokazują nową ideę analitycznych metod analizy energochłonności w zastosowaniu do dużych odbiorców przemysłowych. Jej skuteczności dowodzono na przykładzie wybranego obiektu przemysłu spożywczego. Metoda ta jest rozwinięciem dotychczasowych metod wskaźnikowych. Autorską nowością jest wykorzystanie charakterystyk energetycznych procesów technologicznych do wyznaczania referencyjnych...
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Modeling of Performance, Reliability and Energy Efficiency in Large-Scale Computational Environment
PublikacjaLarge scale of complexity of distributed computational systems imposes special challanges for prediction of quality in such systems.Existing quality models for lower-scale systems include functionality,performance,reliability,flexibility and usability.Among these attributes,performance and reliability have a particular significance to the large-scale systems computing quality modeling due to their strong dependence on the system...
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Optimization of Nuclear Power Share in the Structure of Electricity Production in Poland in Time Perspective by 2060
PublikacjaThe author of this paper presented the results of a system analysis using MARKAL model, aiming at the optimization of nuclear power share in power generation structure in Poland in time perspective by 2060. Optimization criterion is the minimization of the objective function, i.e. the total cost of energy system, taking into account constraints related to CO2, SOx and NOx emissions and obligatory shares of electricity from renewable...
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Przydział narzędzi obróbkowych a efektywność szeregowania zadań produkcyjnych
PublikacjaThe paper addresses issues concerning the analysis of tool flow within a multi-machine machining cell, designated to small batch manufacturing a definite spectrum of prismatic parts. The approach utilises a method for job and tool allocation to work centres with limited number of machines and capacity of tool resources, based on the analysis of formalised relations: job - tool sets required. Selected allocation strategies are considered...
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Hybrid energy storage forelectric multiple units to operate at the partially electrified line Gdynia -Hel
PublikacjaThe article presents calculations enabling the selection of an on-board energy storage device to replace diesel-powered trains with modern storage multiple units on the example railway line Gdynia Główna -Hel. The pioneering and currently used storage electric multiple units, mainly in Europe, were presented. The condensed results of the inventory of the line in question, including the technical condition...
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The instantaneous frequency rate spectogram
PublikacjaAn accelerogram of the instantaneous phase of signal components referred to as an instantaneous frequency rate spectrogram (IFRS) is presented as a joint time-frequency distribution. The distribution is directly obtained by processing the short-time Fourier transform (STFT) locally. A novel approach to amplitude demodulation based upon the reassignment method is introduced as a useful by-product. Additionally, an estimator of energy...
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Modular Approach for Modelling Warming Up Process in Water Installations with Flow-Regulating Elements
PublikacjaThe paper presents a new method for modelling the warming up process of a water system with elements regulating the flow in a stochastic manner. The paper presents the basic equations describing the work of typical elements which the water installation is composed of. In the proposed method, a new computational algorithm was used in the form of an iterative procedure enabling the use of boundary conditions that can be stochastically...
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Technologie prośrodowiskowe dla budynków miejskich
PublikacjaWspółczesne duże miasta na całym świecie charakteryzują się dużą i wciąż rosnącą intensywnością zabudowy. Jest to tendencja utrwalona, którą pogłębia idea „miasta zwartego” jako rozwiązania dla problemu nadmiernego rozrastania terytorialnego i rozpraszania się struktury terenów miejskich. Jednocześnie realną potrzebą współczesnych miast jest poprawa jakości ich środowiska (eliminacja zanieczyszczeń, minimalizacja zjawiska miejskiej...
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Sampling Strategies: Statistics of Sampling
PublikacjaEach step of the analytical procedure has a significant influence on the final result of the analysis. In the majority of cases the analytical procedure encompasses sampling because the analysis of the entire object (material) is usually not possible. Thus it is necessary to include the uncertainty related to sampling procedure in the uncertainty budget calculations. In the paper: the most important properties of the analysed...
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Multidisciplinary approach to the assessment of historic structures based on the case of a masonry bridge in Galicia (Spain)
PublikacjaThe paper presents a general method to evaluate a masonry structure with a complex geometry and unknown material properties. This multidisciplinary approach integrates close range digital photogrammetry,ground probing radar (GPR) and finite elements analysis (FEM) to analyse a masonry bridge. The resulting information from photogrammetry and radar is applied to define a 3D model, which is then used to simulate the behaviour of...
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Experimental investigations on heat transfer enhancement in shell coil heat exchanger with VARIABLE Baffles GEOMETRY
PublikacjaThe paper presents the possibility of using passive intensification of heat transfer in the form of baffles to increase the energy efficiency of the shell and coil heat exchanger. The experiment was carried out by using a modular coil heat exchanger in the form of an electric heater. Water was used as a working fluid with constant thermal-flow parameters at the inlet of the module. It should be noted that experiments were made...
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Heat transfer intensification by enlarged surface roughness in the plate heat exchanger
PublikacjaIn the paper an experimental analysis of passive heat transfer intensification technique employed in the case of the plate heat exchanger is presented. The passive intensification was obtained by a modification of the heat transfer surface. The roughness of surface was increased by a use of glass micro-beads. Single-phase convective heat transfer in the water-water system was studied. The experiment was accomplished in two stages....
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New hybrid quadrature schemes for weakly singular kernels applied to isogeometric boundary elements for 3D Stokes flow
PublikacjaThis work proposes four novel hybrid quadrature schemes for the efficient and accurate evaluation of weakly singular boundary integrals (1/r kernel) on arbitrary smooth surfaces. Such integrals appear in boundary element analysis for several partial differential equations including the Stokes equation for viscous flow and the Helmholtz equation for acoustics. The proposed quadrature schemes apply a Duffy transform-based quadrature...
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Digestate Quality Originating from Kitchen Waste
PublikacjaThis paper examines the influence of biomass directed to anaerobic digestion on the quality of digestate, specifically focusing on the presence of undesirable substances, such as plastics, including biodegradable ones. It analyses the susceptibility of selected bioplastics to degradation and addresses the problem of reliable identification of microplastics in both feedstock—directed to anaerobic digestion—and produced digestate....
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Mohammad Hossein Ghaemi dr inż.
OsobyMohammad Hossein Ghaemi (ur. 1967), adiunkt Wydziału Oceanotechniki i Okrętownictwa (WOiO) PG w Katedrze Automatyki i Energetyki. Jest absolwentem Uniwersytetu Teherańskiego z zakresu mechaniki ciała stałego, a także PG na kierunku Oceanotechnika. Uzyskał stopień doktora nauk technicznych na PG w 2004 roku. Od 1995 roku pracuje na WIMiO PG (do 2020 r. WOiO PG) i prowadzi zajęcia dydaktyczne i badania naukowe w zakresie automatyki...
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Quality Evaluation of Agricultural Distillates Using an Electronic Nose
PublikacjaThe paper presents the application of an electronic nose instrument to fast evaluation of agricultural distillates differing in quality. The investigations were carried out using a prototype of electronic nose equipped with a set of six semiconductor sensors by FIGARO Co., an electronic circuit converting signal into digital form and a set of thermostats able to provide gradient temperature characteristics to a gas mixture. A volatile fraction...
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ANALIZA NUMERYCZNA WPŁYWU POZIOMU MORZA NA PRZEBIEG WEZBRAŃ W NADMORSKICH CIEKACH POWIERZCHNIOWYCH NA PRZYKŁADZIE POTOKU STRZYŻA W GDAŃSKU
PublikacjaW dzisiejszych czasach coraz większym problemem stają się podtopienia na terenach zurbanizowanych. Biorąc to pod uwagę, należy większą wagę przyłożyć do prawidłowego obliczania przepustowości koryta. Jednym z czynników wpływających na nie są warunki na odpływie. W przypadku potoków nadmorskich zależą one ściśle od poziomu morza. W pracy podjęto próbę wyznaczenia wpływu poziomu morza na przebieg wezbrań w nadmorskich ciekach powierzchniowych....
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AN OVERVIEW OF HEAT TRANSFER ENHANCEMENT BASED UPON NANOPARTICLES INFLUENCED BY INDUCED MAGNETIC FIELD WITH SLIP CONDITION VIA FINITE ELEMENT STRATEGY
PublikacjaThe mathematical model of heat generation and dissipation during thermal energy transmission employing nanoparticles in a Newtonian medium is investigated. Dimensionless boundary layer equations with correlations for titanium dioxide, copper oxide, and aluminium oxide are solved by the finite element method. Parameters are varied to analyze their impact on the flow fields. Various numerical experiments are performed consecutively...
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An Easy and Ecological Method of Obtaining Hydrated and Non-Crystalline WO3−x for Application in Supercapacitors
PublikacjaIn this work, we report the synthesis of hydrated and non-crystalline WO3 flakes (WO3−x) via an environmentally friendly and facile water-based strategy. This method is described, in the literature, as exfoliation, however, based on the results obtained, we cannot say unequivocally that we have obtained an exfoliated material. Nevertheless, the proposed modification procedure clearly affects the morphology of WO3 and leads to loss...
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Metoda diagnostyki cieplno-przepływowej turbin parowych wykorzystująca elementy algorytmów genetycznych
PublikacjaRozprawa doktorska poświęcona jest opisowi budowania metody diagnostyki cieplno-przepływowej z wykorzystaniem elementów algorytmów genetycznych. Do tworzenia założeń i algorytmów metody posłużono się przykładem funkcjonowania bloku elektrowni kondensacyjnej ze szczególnym uwzględnieniem układu łopatkowego turbiny parowej. Celem pracy jest zbudowanie metody diagnostyki cieplno-przepływowej. Zadaniem metody jest przeprowadzenie procesu...
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Review on robust laser light interaction with titania – Patterning, crystallisation and ablation processes
PublikacjaTitanium dioxide is regarded as a very promising semiconducting material that is widely applied in many everyday-use products, devices, and processes. In general, those applications can be divided into energy or environmental categories, where a high conversion rate, and energy and power density are of particular interest. Therefore, many efforts are being put towards the elaboration of novel production routes, and improving the...
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Probabilistic estimation of diverse soil condition impact on vertical axis tank deformation
PublikacjaThe calculations of fuel tanks should take into account the geometric imperfections of the structure as well as the variability of the material parameters of the foundation. The deformation of the tank shell can have a significant impact on the limit state of the structure and its operating conditions. The paper presents a probabilistic analysis of a vertical-axis, floating-roof cylindrical shell of a tank with a capacity of 50000...
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Annealing Rate as a Crucial Parameter Controlling the Photoelectrochemical Properties of AuCu Mosaic Core–Shell Nanoparticles
PublikacjaThermal processing is an essential step during the synthesis of various metal nanostructures and for tailoring their morphology, optical, and electrochemical properties. Herein, a profound impact of the annealing rate and time on photoactivity of gold–copper nanostructures by changes in the position and alignment of energy levels and surface states is reported. AuCu nanoparticles (NPs) are fabricated by sputtering of thin metal...
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Provenance studies on Late Neolithic amber ornaments from North-East Poland
PublikacjaThe area of North-East Poland was in prehistory, and still is today, an area with easy access to amber as a raw material, as is evidenced in part by numerous Late Neolithic (3rd millennium) amber workshops located in the Gulf of Gdańsk and Żuławy Wiślane (Vistula Fens). Given this fact, it is surprising that only a few finished amber products have been recovered from this area. Among them are unique ornaments from the Late Neolithic...
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Joint experimental and theoretical study on low-energy elastic electron scattering by gaseous alkynes: Differential cross sections, shape resonances, and methylation effects
PublikacjaA detailed comparison of experimental and theoretical elastic cross sections for low-energy electron scattering by ethyne, taken earlier in our group by Gauf et al. [Phys. Rev. A 87, 012710 (2013)], and some of its methylated derivatives, propyne, and the isomers 1-butyne and 2-butyne, taken here, are presented. The present differential cross sections were measured at incident electron energies ranging from 1 eV to 30 eV and...
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Numerical Modelling of Connections Between Stones in Foundations of Historical Buildings
PublikacjaThe aim of this paper is to analyse the behaviour of old building foundations composed of stones (the main load-bearing elements) and mortar, based on numerical analysis. Some basic aspects of historical foundations are briefly discussed, with an emphasis on their development, techniques, and material. The behaviour of a foundation subjected to the loads transmitted from the upper parts of the structure is described...
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Dissociative ionization dynamics of dielectric gas C3F7CN
PublikacjaFluoronitrile C3F7CN is a promising candidate for the replacement of SF6 dielectric gas in high-voltage insulation. We present a combined experimental and theoretical study on its ionization dynamics probed in the 0-100 eV energy range. We exploited the total ion collection technique to determine the absolute ionization cross section, mass spectrometry to determine the fragment branching ratios and ab initio nonadiabatic molecular...
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On the non-linear dynamics of torus-shaped and cylindrical shell structures
PublikacjaIn this study, the non-linear dynamic analysis of torus-shaped and cylindrical shell-like structures has been studied. The applied material is assumed as the functionally graded material (FGM). The structures are considered to be used for important machines such as wind turbines. The effects of some environmental factors on the analysis like temperature and humidity have been considered. The strain field has been calculated in...
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Strong ellipticity conditions and infinitesimal stability within nonlinear strain gradient elasticity
PublikacjaWe discuss connections between the strong ellipticity condition and the infinitesimal instability within the nonlinear strain gradient elasticity. The strong ellipticity (SE) condition describes the property of equations of statics whereas the infinitesimal stability is introduced as the positive definiteness of the second variation of an energy functional. Here we establish few implications which simplify the further analysis...
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Time-frequency analysis of acoustic signals using concentrated spectrogram
PublikacjaThe paper presents improved method of time-frequency (TF) analysis of discrete-time signals. The method involves signal's local group delay (LGD) and channelized instantaneous frequency (CIF) to purposely redistribute all Short-time Fourier transform (STFT) lines. Additionally, the energy concentration index (ECI) and some histogram-like statistics are used to evaluate readability of estimated TF distributions of the energy. Recorded...
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Modeling of Performance, Reliability and Energy Efficiency in Large-Scale Computational Environments
PublikacjaLarge scale of complexity of distributed computational systems imposes special challenges for prediction of quality in such systems. Existing quality models for lower-scale systems include functionality, performance, reliability, flexibility and usability. Among these attributes, performance and reliability have a particular significance to the large-scale systems computing quality modeling due to their strong dependence on the...
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Experimental and numerical study of thermal and electrical potential of BIPV/T collector in the form of air-cooled photovoltaic roof tile
PublikacjaAmong renewable energy sources, Building-Integrated Photovoltaic/Thermal (BIPV/T) systems are gaining increasing interest. To improve their economic competitiveness, technologies that increase their efficiency are searched for. The paper is devoted to evaluating the impact of various air-cooling configurations on the thermal and electrical performance of a photovoltaic roof tile. A numerical model of the own experimental system...
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Weak localization competes with the quantum oscillations in a natural electronic superlattice: The case of Na1.5(PO2)4(WO3)20
PublikacjaWe report an investigation of the combined structural and electronic properties of the bronze Na1.5(PO2)4(WO3)20. Its low-dimensional structure and possible large reconstruction of the Fermi surface due to charge density wave instability make this bulk material a natural superlattice with a reduced number of carriers and Fermi energy. Signatures of multilayered two-dimensional (2D) electron weak localization are consequently reported,...
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Assessment, optimisation and working fluid comparison of organic rankine cycle combined with negative CO2 gas power plant system
PublikacjaThis study aims to investigate the application of the Organic Rankine Cycle (ORC) as an alternative to low-pressure expansion in the negative CO2 power plant (nCO2PP). The reason for this study is that a detailed analysis of nCO2PP indicates a certain amount of waste heat present in the exhaust gas from the high-to-intermediate pressure gas turbine. Some of this energy can be used by the application of the expansion in a low-pressure...
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Curved Surface Minijet Impingement Phenomena Analysed with ζ-f Turbulence Model
PublikacjaThe jet impingement phenomenon plays an important role among the heat transfer intensification methods. Very often its application and analyses refer to simple flat surfaces, while there is a lack of information in the literature for cases addressing curved surfaces. In the present work, the single jet impingement on the non-flat (concave and convex) surface is studied for a wide range of geometries, which originate from the mini-jet...
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Emissions and toxic units of solvent, monomer and additive residues released to gaseous phase from latex balloons
PublikacjaThis study describes the VOCs emissions from commercially available latex balloons. Nine compounds are determined to be emitted from 13 types of balloons of different colors and imprints in 30 and 60°C. The average values of total volatile organic compounds (TVOCs) emitted from studied samples ranged from 0.054 up to 7.18 μg∙g-1 and from 0.27 up to 36.13 μg∙g-1 for 30oC and 60oC, respectively. The dataset is treated with principal...
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Routing decisions independent of queuing delays in broadband leo networks
PublikacjaThis paper presents an analysis of queuing and propagation delays of Inter-Satellite Links (ISLs) in broadband Low-Earth Orbit (LEO) satellite networks. It is shown that queuing delays are negligible in all reasonable working conditions of the broadband ISL network. This fact makes it possible to simplify the routing protocols in such networks and permits using already known multi-commodity flow solutions for routing. The performance...
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Reduction of Computational Complexity in Simulations of the Flow Process in Transmission Pipelines
PublikacjaThe paper addresses the problem of computational efficiency of the pipe-flow model used in leak detection and identification systems. Analysis of the model brings attention to its specific structure, where all matrices are sparse. With certain rearrangements, the model can be reduced to a set of equations with tridiagonal matrices. Such equations can be solved using the Thomas algorithm. This method provides almost the same values...
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THERMODYNAMIC ANALYSIS OF A GENERATION IV SCWR NUCLEAR POWER PLANT CYCLE
PublikacjaThis article presents a flow and thermodynamic analysis of a Generation IV nuclear cycle. An SCWR (Supercritical water reactor) is a high temperature and high pressure reactor that uses water at a temperature above its thermodynamic critical point as the working fluid. The cycle used for the calculations consists of one interstage superheater and 7 regenerative heat exchangers. Division pressure was optimized in view of the cycle efficiency,...
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Comparison of buckling resistance of columns modelled by beam and shell elements using non-linear analysis
PublikacjaThe aim of the paper is to investigate the stability process in the axially compressed columns modelled by beam and shell elements using static and dynamic finite element analysis by taking both the geometric and material non-linearity into account. The perfect columns and columns with geometric imperfections were analysed. The differences between the results of static and dynamic analyses in shell and beam models were discussed.
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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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Random field modelling of mechanical behaviour of corroded thin steel plate specimens
PublikacjaThe objective of this work is to explore the possibility of corrosion degradation modelling of thin steel plate specimens with the use of random field approach. The mechanical properties are obtained via the nonlinear Finite Element Analysis with the use of an explicit dynamic solver. The fully nonlinear material model is adopted to obtain the proper stress-strain response. Sensitivity analysis considering the main statistical...
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Thermodynamic analysis of the double Brayton cycle with the use of oxy combustion and capture of CO2
PublikacjaIn this paper, thermodynamic analysis of a proposed innovative double Brayton cycle with the use of oxy combustion and capture of CO2, is presented. For that purpose, the computation flow mechanics (CFM) approach has been developed. The double Brayton cycle (DBC) consists of primary Brayton and secondary inverse Brayton cycle. Inversion means that the role of the compressor and the gas turbine is changed and firstly we have expansion...
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Compressible gas density measurement by means of Fourier analysis of interferograms
PublikacjaThis paper describes a method for nonintrusive compressible gas density measurement by means of automated analysis of interferograms using FFT (Fast Fourier Transform), and its implementation using DFT (Discrete Fourier Transform), that does make this measurement technique a fairly valuable and accessible experimental method. The presented approach makes it possible to use the finite fringe setting of the interferometer, thus reducing...
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Mathematical and numerical modelling,W,IDE-EMSS,IIst,sem.01,lato,2023/24 (PG_00057379)
Kursy OnlineModelling of controlled mechanical systems by the mixed method of rigid and flexible finite elements: The finite element volume problems. Dynamics of multibody systems. Modelling of stationary closed loop systems. Modelling of systems whose configuration changes with time. Modelling of nonlinear controlled systems. Optimal control at energy performance index: Control of continuous nonstationary systems in domain of generalised...
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Mathematical and Numerical Modelling, L, IDE IInd, sem.01, summer, 2022/23(00057379)
Kursy OnlineModelling of controlled mechanical systems by the mixed method of rigid and flexible finite elements: The finite element volume problems. Dynamics of multibody systems. Modelling of stationary closed loop systems. Modelling of systems whose configuration changes with time. Modelling of nonlinear controlled systems. Optimal control at energy performance index: Control of continuous nonstationary systems in domain of generalised...
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Study on deformed steel columns subjected to impact load due to soft-storey failure in buildings during earthquakes
PublikacjaThe so called soft-storey failure is one of the most typical types of damage induced in buildings as the result of earthquake excitation. It has been observed during ground motions that the failure of an upper soft storey of a structure results in large vertical impact load acting on the lower floors. If the resistance of the structural members of the lower storeys is not sufficient it may further lead to progressive collapse of...
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Exploring synergistic effects in physical-chemical activation of Acorus calamus for water treatment solutions
PublikacjaThe research proposed a novel method of obtaining sorption material from readily available Acorus calamus bio- mass through a combination of physical and chemical activation processes. The material with the highest specific surface area (1652 m2 g−1) was obtained by physical activation with CO2, followed by chemical activation with KOH. Reversing the order of activation methods resulted in a lower specific surface area (1014 m2...
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Comparison of AHP and Numerical Taxonomy Methods Based on Biogas Plant Location Analysis
PublikacjaThe paper presents a comparison of the multi-criteria Analytic Hierarchy Process (AHP) method and numerical taxonomy in biogas plant location selection. Biogas plants are sources that will significantly contribute to the implementation of the provisions of the energy and climate package for Poland by 2030. Increasing the share of energy produced from renewable sources, e.g. biogas plants, will increase the country’s energy security....
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Excess molar volume and viscosity deviation for binary mixtures of gamma-butyrolactone with dimethyl sulfoxide
PublikacjaThe densities of binary liquid mixtures of dimethyl sulfoxide and gamma-butyrolactone at (293.15, 298.15, 303.15 and 313.15) K and viscosity at T=298.15 K have been measured at atmospheric pressure over theentire range of concentration. From these data the excess molar volumes VE at (293.15, 298.15, 303.15 and 313.15) K and the viscosity deviation, the excess entropy, and the excess Gibbs energy of activation for viscous flow at...