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Model of noise sources in supercapacitors
PublikacjaThe paper presents detailed model of noise sources in supercapacitors. Noise phenomena observed in supercapacitors may be used as a diagnostic tool for assessment of supercapacitor quality or degradation mechanisms (e.g. corrosion of the electrodes or cloggin g up the pores) during ageing. Therefore, it is important to consider where noise is generated. The equivalent circuit of noise sources existing...
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ANALYSIS OF THE PUNCHING FAILURE MECHANISM IN WORKING PLATFORMS
PublikacjaPaper presents an analysis of the shear failure mechanism which occurs from the punching of a working platform layer in relation to its thickness, grain size arrangement and mechanical properties, taking into consideration the interaction with soft subgrade. The study is based on the observations of performance of natural scale structures (Streefkerk) and the results of model investigations numerically represented with the use...
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Improvement of Imperfect String Matching Based on Asymetric n-Grams
PublikacjaTypical approaches to string comparing treats them as either different or identical without taking into account the possibility of misspelling of the word. In this article we present an approach we used for improvement of imperfect string matching that allows one to reconstruct potential string distortions. The proposed method increases the quality of imperfect string matching, allowing the lookup of misspelled words without significant...
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LABORATORY STAND FOR INVESTIGATIONS OF THE QUICK - CHANGING TEMPERATURE OF GAS FLOWING IN THE PISTON COMPRESSOR OUTLET CHANNEL
PublikacjaThis paper presents a laboratory stand, created as a part of work on the doctor dissertation, intended for investigation of heat and flow processes taking place in the Espholin H3S piston compressor outlet channel. The test stand elements and their configuration within the stand are described. Discussed are also problems connected with the quick-changing measurement technique, solutions which have been proposed so far in that technology...
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Dilemmas associated with the implementation of quality management systems in Polish smaller health care units
PublikacjaThe article presents the considerations and recommendations for the implementation of the process-oriented quality management systems (QMS) in small health care units. As an example, the unit providing services for children with disabilities (therapy and rehabilitation) localized in northern part of Poland have been selected. The essential elements of the implementation of the quality system, taking into account the objectives...
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Chronographic Imprint of Age-Induced Alterations in Heart Rate Dynamical Organization
PublikacjaBeat-to-beat changes in the heart period are transformed into a network of increments between subsequent RR-intervals, which enables graphical descriptions of short-term heart period variability. Three types of such descriptions are considered: (1) network graphs arising from a set of vertices and directed edges, (2) contour plots of adjacency matrices A, representing the networks and transition matrices T, resulting from A, and (3)...
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Effectiveness of a dual surface modification of metallic interconnects for application in energy conversion devices
PublikacjaA dual surface modification of an SOFC metallic interconnect with a Gd2O3 layer and an MnCo2O4 coating was evaluated. The tested samples were oxidized for 7000 h in air at 1073 K. Oxidation products were characterized using XRD, SEM-EDS, and confocal Raman imaging, and ASR was measured. The effect of gadolinium segregation at grain boundaries in Cr2O3 was evaluated using S/TEM-EDS. Area specific-resistance was measured and fuel...
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Wytrzymałość pętli wplatanych na linach podwójnie plecionych
PublikacjaCechą wyróżniającą statki żaglowe z grona innych obiektów pływających są żagle. To cecha widoczna, za którą kryją się mniej romantyczne elementy, takie jak maszty, liny i osprzęt. Rozpostarcie białych płócien na maszcie i następnie żeglowanie wymaga sprawnego operowania nimi, co wiąże się z doborem odpowiedniego ich zestawu, ułożenia i napięcia. To maszty są kręgosłupem takielunku, a liny jego mięśniami i ścięgnami. Do poprawnego...
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Technical and Economic Analysis of the Implementation of Selected Variants of Road Investment
PublikacjaThe aim of the article is to analyze three variants of modernization and reconstruction of a road intersection, which in practice is the cause of numerous collisions and accidents. Detailed design solutions are presented for them. The aim of the analyses is to indicate an effective solution that, taking into account technical modifications of the road system elements, will ensure the functionality of the road system to the highest...
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Influence of dissolved organic nitrogen on surface waters
PublikacjaThe aim of this study was to determine the susceptibility of dissolved organic nitrogen (DON) contained in biologically treated wastewater disposed from municipal wastewater treatment plants (WWTPs) to biodegradability and bioavailability in a water environment. Additionally an evaluation was performed of the participation of this organic nitrogen fraction, including bioavailable DON (bDON), in the nitrogen balance for the Baltic...
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Investigation of the Efficiency of a Dual-Fuel Gas Turbine Combustion Chamber with a Plasma‒Chemical Element
PublikacjaThe study is devoted to the possibility of increasing the efficiency of the working process in dual-fuel combustion chambers of gas turbine engines for FPSO vessels. For the first time, it is proposed to use the advantages of plasma‒chemical intensification of the combustion of hydrocarbon fuels in the dual-fuel combustion chambers, which can simultaneously operate on gaseous and liquid fuels. A design scheme of a combustion chamber...
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Nitrogen transformation during fermentation in agricultural biogas plants
PublikacjaThe aim of the present study was to determine changes in the organic nitrogen fraction in the liquid fraction of the digestate during laboratory tests of mono- and co-digestion. Three agricultural wastes were tested: distillery residue, cattle slurry and corn silage. In the mono-fermentation tests, the initial total nitrogen concentration depended on the feedstock used. As a result of the hydrolysis and ammonification of the organic...
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Robust asymptotic super twisting sliding mode observer for non-linear uncertain biochemical systems
PublikacjaThe problem of state estimation (reconstruction of the state vector) for a given class of biochemical systems under uncertain system dynamics has been addressed in this paper. In detail, the bioreactor at a water resource recovery facility represents the considered biochemical systems. The biochemical processes taking place in the bioreactor have been modelled using an activated sludge model. Based on this model, an appropriate...
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Preliminary study of linear viscoelasticity limits of cold recycled mixtures determined in Simple Performance Tester (SPT)
PublikacjaThe publication presents methodology developed for determination of linear viscoelasticity limits for cold recycled mixtures with cement and bituminous emulsion using Simple Performance Tester (SPT). Methodology was verified on reference materials (PCV and steel dummy specimens, cement concrete and asphalt concrete) to comply with elasticity and viscoelasticity theory. The developed methodology enabled determination of linear viscoelasticity...
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Comparison of single microjet cooling with water, ethanol and HFE7100 as test fluids
PublikacjaThe paper presents the investigation of a single microjet cooling forming an thin liquid film on the impingement surface of specially designed rig. The basis of microjet technology is to produce laminar jets, which when impinging the surface have a very high kinetic energy at the stagnation point. Applied technology of jet production can result with the size of jets ranging from 20 to 500μm in breadth and 20 to 100μm in width....
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Filtering EBG Structures Implemented in Coplanar Waveguide Feedline of Planar Slot Antenna
PublikacjaA novel compact dual-band slot antenna fed by a coplanar waveguide (CPW) incorporating electromagnetic band gap (EBG) structures has been proposed. At first, a classic wideband slot antenna fed by a CPW, dedicated to work in 2 ÷ 18 GHz band, has been designed. Subsequently, by adding simple EBG filtering structures into a CPW feedline, a dual-band performance ranging from 2.5 to 5.3 GHz and from 13.5 to 16.3 GHz, with the voltage...
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Cylindrical orifice testing in laminar flow with the orifice diameter ratio β = 0.5
PublikacjaThe paper presents the results of an experimental study of a cylindrical orifice with the orifice diameter ratio β = 0.5 and the flow opening length‑to‑diameter ratio L/d = 1, with hydraulic oil flowing in the DN50 measuring channel. The measurements of the values characterising the oil flow were made in the laminar flow regime, for the Reynolds numbers ranging between Re = 100 to 950. Based on the experimental tests, standard...
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Experimental study of flow boiling pressure drop and heat transfer of R1233zd(E) at moderate and high saturation temperatures
PublikacjaThe paper presents the results of experimental study of flow boiling of R1233zd(E) in minichannel at moderate and high saturation temperatures. The heat transfer coefficient and pressure drop were measured for flow boiling in a stainless steel tube with 2 mm inside diameter and a length of 300 mm. Experiment has been conducted for saturation temperatures ranging from 83 to 145 °C which corresponds to values of reduced pressures...
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The spatial planning of industrial areas in an urbanized area for cargo, in the development of inland waterway transport
PublikacjaSpatial planning, taking into account the configuration of the surface, i.e. its shape (relief) and the presence and mutual location of objects and points of characteristic water ports, is a derivative of several natural, economic, market, technical, social and political factors. It depends on the destination port, the planned structure of trade in cargo, the forecasted traffic of ships, passageways, the technology of reloading...
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Bistability in a One-Dimensional Model of a Two-Predators-One-Prey Population Dynamics System
PublikacjaIn this paper, we study a classical two-predators-one-prey model. The classical model described by a system of three ordinary differential equations can be reduced to a one-dimensional bimodalmap. We prove that this map has at most two stable periodic orbits. Besides, we describe the bifurcation structure of the map. Finally, we describe a mechanism that leads to bistable regimes. Taking this mechanism into account, one can easily...
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Evolutionary Ship Track Planning within Traffic Separation Schemes – Evaluation of Individuals
PublikacjaThe paper presents an extended version of the author’s Evolutionary Sets of Safe Ship Trajectories method. The method plans safe tracks of all ships involved in an encounter including speed reduction manoeuvres, if necessary, and taking into account Rule 10 of COLREGS, which specifies ships’ behaviour within Traffic Separation Schemes governed by IMO. The paper focuses on the evaluation phase of the evolutionary process and shows...
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Approach to evaluation of time to the critical degradation of ship pipelines
PublikacjaIn the article an approach to the problem of estimating time to the critical degradation of ship pipelines is considered. Such an assessment would consist of six stages. The fundamental idea is to include to the estimation of time to failure of pipelines such elements like: materials that the pipelines are made, destructive physical phenomena taking place in them and applied means of protection. The result of that evaluation should...
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Nonlinear FEM 2D failure onset prediction of composite shells based on 6-parameter shell theory
PublikacjaWithin the framework of the nonlinear 6-parameter shell theory with the drilling rotation and asymmetric stress measures, the modifications of Tsai-Wu and Hashin laminate failure initiation criteria are proposed. These improvements enable to perform first ply failure estimations taking into account the non-symmetric stress measures. In order to check the validity of the proposed criteria, finite element analyses are performed with...
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Modelling of in-plane wave propagation in a plate using spectral element method and Kane-Mindlin theory with application to damage detection
PublikacjaThis paper presents results of experimental and numerical analyses of in-plane waves propagatingin a 5 mm-thick steel plate in the frequency range of 120-300 kHz. For such a thickness/frequency ratio,extensional waves reveal dispersive character. To model in-plane wave propagation taking into account thethickness-stretch effect, a novel 2D spectral element, based on the Kane-Mindlin theory, was formulated. Anapplication of in-plane...
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Analysis of possible application of high-temperature nuclear reactors to contemporary large-output steam power plants on ships
PublikacjaThis paper is aimed at analysis of possible application of helium to cooling high-temperature nuclear reactor to be used for generating steam in contemporary ship steam-turbine power plants of a large output with taking into account in particular variable operational parameters. In the first part of the paper types of contemporary ship power plants are presented. Features of today applied PWR reactors and proposed HTR reactors...
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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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Investigation of the aerodynamics of an innovative verticalaxis wind turbine
PublikacjaThis paper presents a preliminary three dimensional analysis of the transient aerodynamic phenomena occurring in the innovative modification of classic Savonius wind turbine. An attempt to explain the increased efficiency of the innovative design in comparison with the traditional solution is undertaken. Several vorticity measures such as enstrophy, absolute helicity and the integral of the velocity gradient tensor second invariant...
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Flexoelectricity and apparent piezoelectricity of a pantographic micro-bar
PublikacjaWe discuss a homogenized model of a pantographic bar considering flexoelectricity. A pantographic bar consists of relatively stiff small bars connected by small soft flexoelectric pivots. As a result, an elongation of the bar relates almost to the torsion of pivots. Taking into account their flexoelectric properties we find the corresponding electric polarization. As a results, the homogenized pantographic bar demonstrates piezoelectric...
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Metal-Organic Frameworks in Green Analytical Chemistry
PublikacjaTaking into consideration the rapid expansion of MOFs applications in the analytical chemistry area, it is important to evaluate the existing and future analytical MOF-based methods according to GAC principles. From this point of view, eco-friendly MOFs-based methods should include features such as: green design and synthesis of MOF, evaluation of toxicity issues of MOFs, and incorporation of MOFs in GAC methods. This Chapter will...
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Evaluation of thermal cracking probability for asphalt concretes with high percentage of RAP
PublikacjaThe paper presents determination of the probability of thermal cracking of asphalt mixtures with different reclaimed asphalt pavement (RAP) content on the basis of laboratory tests and analytical evaluation using thermal stress development method. Probability was evaluated taking into consideration: the type and gradation of the mixture and the quality and content of RAP. Thermal stresses were determined using two models: elastic and...
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Development of the Polish energy sector through transformation and harmonization with the European energy and climate policy
PublikacjaThe paper presents the dilemmas of energy sector development vs European energy policy due to the way of energy transition. The identification of barriers and opportunities for the development of the power industry is presented. The possibilities of using modern energy technologies for the processes of energy transformation are described. The path useful to achieving climate and energy goals is determined. The new method of electricity...
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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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Morphology of bio-based polyurethane composites filled by mer-cerized or silanized natural fibres
PublikacjaBio-composites are materials which possess unique properties and undergo biodegra-dation under specific conditions. Bio-composites belong to the group of materials produced with the use of renewable raw materials. They contain reinforcement, mainly in the form of natural fiber, which has high stiffness and resistance; filler powders are less frequently used. Significant features of natural fibers are elongation, density, thermal...
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Analysis and Detection of Faults at Insulated Conductors of Overhead Medium Voltage Lines
PublikacjaThe paper dealt with the issue of breakdowns detection of isolated hanging wires on the medium-voltage transmission. The main aim of article is to describe the function of created breakdowns detector and evaluation its. The breakdowns detector is created based in indicators of faults such as touch between tree limbs and insulated wire, touch tree limbs with several phases or fall insulated wire on the ground. Breakdowns detector...
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Fluorescence of p-hydroxyazobenzocrowns – Tautomeric equilibrium effect
PublikacjaThe spectroscopic properties of a series of para-hydroxyazobenzocrowns, including three novel compounds, were investigated using UV–Vis absorption and emission spectroscopy. This study presents, for the first time, determined quantum yield (QY) values for macrocycles of this category, ranging between 0.122 and 0.195. The highest values were obtained for crowns bearing two phenyl substituents in benzene rings. The impact of aromatic...
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Hopf bifurcation in time‐delayed gene expression model with dimers
PublikacjaWe study a mathematical model of gene transcription and protein synthesis with negative feedback. We consider a system of equations taking into account the formation of dimers (i.e., complex formed by two protein monomers), the way in which dimers bind to DNA and time delay in translation process. For the model consisting of three ordinary differential equations with time delay, we derive conditions for stability of the positive...
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Accurate electrothermal modelling of high frequency DC-DC converters with discrete IGBTs in PLECS software
PublikacjaIn the paper, a novel, improved method of the IGBT junction temperature computations in the PLECS simulation software is presented. The developed method aims at accuracy of the junction temperature computations in PLECS by utilising a more sophisticated model of transistor losses, and by taking into account variability of transistor thermal resistance as a function of its temperature. A detailed description of the proposed method,...
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MARKAL LONG-TERM POWER GENERATION SCENARIOS FOR POLAND: INCREASING THE SHARE OF RENEWABLE ENERGY SOURCES BY 2040
PublikacjaIn this paper, renewable energy sources (RES) support mechanisms in Poland was presented with perspectives of proposed support system modifications, discussed in the project of Renewable Energy Act. In addition, MARKAL model of RES support mechanism was presented, taking into account technology-specific multiplication factors. Two model runs with emission trading system in place and two additional runs without emission trade were...
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The Implementation of the Taxonomic Spatial Measure of Development in the Analysis of Convergence in the Standard of Living
PublikacjaThe main goal of this paper is to analyse the existence of the social convergence in the European Union between 19952012. The social convergence refers to a reduction in the dispersion of the standard of living across countries. A taxonomic spatial measure of development was used as the standard of living approximation. The use of the new approach proposed by E. Antczak allowed for an explanation of the disparities in the analysed...
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Występowanie bakterii siarkowych a jakość wód podziemnych ujęcia Osowa
PublikacjaAbstrakt. Microorganisms that live in groundwater should be considered not only from the sanitary-hygienic point of view but also in terms of adverse changes in groundwater chemistry in the aquifer layer and its negative influence on the installed devices. For these reasons, it is important to correct approach to the problem of bacterial contamination of groundwater. The paper presents selected results of physicochemical and bacteriological...
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Important Facts and Observations about Pairwise Comparisons (the special issue edition)
PublikacjaThis study has been inspired by numerous requests for clarification from researchers who often confuse Saaty’s Analytic Hierarchy Process (AHP) with the pairwise comparisons (PC) method, taking AHP as the only representation of PC. This study should be regarded as an interpretation and clarification of past investigations of PC. In addition, this article is a reflection on general PC research at a higher level of abstraction: the...
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Toward Intelligent Recommendations Using the Neural Knowledge DNA
PublikacjaIn this paper we propose a novel recommendation approach using past news click data and the Neural Knowledge DNA (NK-DNA). The Neural Knowledge DNA is a novel knowledge representation method designed to support discovering, storing, reusing, improving, and sharing knowledge among machines and computing systems. We examine our approach for news recommendation tasks on the MIND benchmark dataset. By taking advantages of NK-DNA, deep...
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Experimental study of boiling heat transfer in the stagnation point of water microjet
PublikacjaIn the paper presented is a comparison of computational model with experimental data. Numerical model of liquid film with phase change in the stagnation zone due to impingement of the microjet is more widely presented in authors previous work. The radius on which theevaporation process is taking place can be determined from the energy balance on the element of the plate. That radius has also been confirmed experimentally in the...
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The impact of technological and structural changes in the national economy on the labour-capital relations
PublikacjaThe aim of the research presented in this paper is to present the relations between labour and capital in the national economy, resulting from technological and structural changes taking place in the years 1991 to 2008. The structure of the paper is as follows. It first presents the functional determinants for the Polish economy in 1991-2008 affecting the phenomenon subject to study. Then it presents the preliminary analysis of...
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Common methods for the chiral determination of amphetamine and related compounds I. Gas, liquid and thin-layer chromatography
PublikacjaThis article reviews the most common, useful methods for the chiral determination of amphetamine (AM) and AM-deriveddesigner drugs in different of matrix, including blood, hair, urine, medicaments or standard solutions, taking into considerationarticles published in the past 15 years. We consider chromatographic methods (e.g., gas, liquid, high-performance liquid, and thinlayer). We describe several types of chiral derivatization...
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Beam on elastic foundation with anticlastic curvature: Application to analysis of mode I fracture tests
PublikacjaA first order correction is proposed taking into account both interface elasticity and transverse anticlastic curvature of flexible substrate(s) in the DCB (and related tests). Adherends are represented by Kirchhoff-Love plates, and the interface by Winkler-type elastic foundation. Two functions are introduced, representing evolution of beam deflection along the sample midline and anticlastic curvature along the plate. A method...
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Shaping of the turnout diverging track with variable curvature sections
PublikacjaThe paper presents an analytical method of shaping the turnout diverging railroad track with variable curvature segments on its length, which in an evident way distinguished it from a typical solution, made up of a single circular arc with no transition curves. Two separate causes including a linear and a nonlinear curvature one in the form of a polynomial have been examined. The obtained solutions of the problem have a universal...
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The entrepreneurship of host cities of the Olympic Games – Between success and social destruction
PublikacjaMany publications focus on the deficit nature of the Olympic Games organisation, when considered from the point of view of host cities – organisers of such events. However, does such an event actually affect the region and the host country in a positive way? The presented article aims at the assessment of the organisation of mass sports events, such as the Olympic Games, taking into consideration entrepreneurial activities which...
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FEM Calculations in Analysis of Steel Subsea Water Injection Flowlines Designing Process
PublikacjaPaper describes the result of theoretical research aimed at assessing the loads and operating conditions of a Coiled Tubing pipeline injecting water, suspended to the mining platform of Lotos Petrobaltic. For this purpose, appropriate calculation models have been developed using the Finite Element Method (FEM), taking into account the nature of the analyzed object and its loads. The analyzes were carried out for two pipes (previously...
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Innovative design of hybrid powered inland vessel
PublikacjaOne of the most demanding task for European countries is rational transportation system taking into account fuel efficient and ecological propulsion. The paper presents innovative design of hybrid powered inland vessel. The most important aspects regarding new design and technical solutions are being presented, including numerical and experimental research on hull form. Combined diesel-electric propulsion supported by solar panel...