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Sensitivity analysis of free torsional vibration frequencies of thin-walled laminated beams under axial load
PublikacjaThe paper addresses sensitivity analysis of free torsional vibration frequencies of thin-walled beams of bisymmetric open cross-section made of unidirectional fibre-reinforced laminate. The warping effect and the axial end load are taken into account. The consideration is based upon the classical theory of thin-walled beams of non-deformable cross-section. The first-order sensitivity variation of the frequencies is derived with...
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On the current state of dovetail wall-corner joints in wooden Greek Catholic churches in Polish Subcarpathia with structural and sensitivity analyses
PublikacjaThis paper describes the current condition of some dovetail joints which form the wall corners of two Greek Catholic churches of wooden construction in Polish Subcarpathia. It also gives the historical background of the sacral architecture of that region. The two structures, which represent the same type of log corner joints are situated in Chotylub and Cewków. The buildings were examined e.g. for damage, wood moisture content,...
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Design Evolution of the Ultrasonic Piezoelectric Motor Using Three Rotating Mode Actuators
PublikacjaThe development process and experimental investigation of the multicell piezoelectric motor is presented in this paper. The proposed design consists of three individual cells integrated into the stator, double rotor, and a preload system. Those elements are combined into a symmetrical structure of the motor. The two new prototypes have been designed, simulated and tested. Finite element numerical analysis is carried out to obtain...
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Portico Farmhouses of the Vistula Delta: Architecture, Current State and Finite Element Modelling of Timber Roof Truss under Material and Cross-section Uncertainty
PublikacjaThe article focuses on the oldest surviving I-type portico houses located in the Vistula Delta, which were built in the 17th and 18th centuries. The study describes the houses’ origins, structure, details of roof structures and technical condition, and it also includes numerical modelling of a roof truss and its mechanical analysis. Numerical models of the roof trusses are defined and analysed by means of the finite element method....
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Preparation and characterisation of iron substituted Mn1.7Cu1.3-xFexO4 spinel oxides (x = 0, 0.1, 0.3, 0.5)
PublikacjaSpinel oxides with the general formula Mn1.7Cu1.3-xFexO4 (x= 0, 0.1, 0.3, 0.5) were prepared and evaluated in this work for their properties at high temperatures. The effect of partially substituting Cu by Fe has not been studied so far for this group of materials and is thus evaluated in this work. Mn1.7Cu1.3-xFexO4 powders were synthesised by a soft chemistry process and studied in terms of crystallographic phase analysis, electrical...
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Fermentative Conversion of Two-Step Pre-Treated Lignocellulosic Biomass to Hydrogen
PublikacjaFermentative hydrogen production via dark fermentation with the application of lignocellulosic biomass requires a multistep pre-treatment procedure, due to the complexed structure of the raw material. Hence, the comparison of the hydrogen productivity potential of different lignocellulosic materials (LCMs) in relation to the lignocellulosic biomass composition is often considered as an interesting field of research. In this study,...
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Variable-fidelity response feature surrogates for accelerated statistical analysis and yield estimation of compact microwave components
PublikacjaAccounting for manufacturing tolerances is an essential part of a reliable microwave design process. Yet, quantification of geometry and/or material parameter uncertainties is challenging at the level of full-wave electromagnetic (EM) simulation models. This is due to inherently high cost of EM analysis and massive simulations necessary to conduct the statistical analysis. Here, a low-cost and accurate yield estimation procedure...
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Geometrically Nonlinear Analysis of Functionally Graded Shells Based on 2-D Cosserat Constitutive Model
PublikacjaIn this paper geometrically nonlinear analysis of functionally graded shells in 6-parameter shell theory is presented. It is assumed that the shell consists of two constituents: ceramic and metal. The mechanical properties are graded through the thickness and are described by power law distribution. Formulation based on 2-D Cosserat constitutive model is used to derive constitutive relation for functionally graded shells. Numerical...
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Disturbances of magnetic field in surrounding of mobile, metalic plate
PublikacjaThe uniform magnetic field of the Earth in the surrounding of a mobile, metalic object undergoes deformation by eddy currents. The influence of the moving conducting object on total magnetic field of the Earth depends on the object's shape, position and speed of the changes relative to the magnetic field's vector of the Earth as well as the electric conductivity and the relative magnetic permeability of the material. The disturbances...
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The project of pull system for storehouse and production line in a company provides electronics
PublikacjaThe chapter below presents how to reduced delivery of the material to production by using a "Kanban schedule board" and related tools from 48 hours and 59 minutes to 41 minutes in a company provides electronics. The solution was found through analysis of the current way of supplying stands and using Just In Time idea, the reduction of ''muda''. To solve the problem was used Kanban card", which has the shape of two triangles joined...
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Wireless Charging Station Design for Electric Scooters: Case Study Analysis
PublikacjaThis study proposes an example of a wireless charging station design for a small-scale vehicle available on the market. The article analyzes basic transmitter inverter topologies and their compensation methods in terms of flexibility of control, tolerance to uncertainty in positioning, and the possibility of decreasing the integration price. Our comprehensive analysis focuses on the battery voltage range, energy capacity, cost,...
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Tunable Dielectric Switching of (Quinuclidinium)[MnCl4] Hybrid Compounds
PublikacjaInorganic−organic hybrid QMnCl (Q = quinuclidinium) crystals were synthesized and characterized. The X-ray and variable-temperature IR/Raman analysis demonstrate that the crystals undergo a reversible structural phase transition, which originates from an order−disorder process and is related to the dynamics of the organic Q cation. Dielectric function measurements disclose a switchability between low (“OFF”) and high (“ON”) dielectric...
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Fault Diagnostics in PEMFC Stacks by Evaluation of Local Performance and Cell Impedance Analysis
PublikacjaStarvation, flooding, and dry‐out phenomena occur in polymer electrolyte membrane fuel cells (PEMFCs), due to heterogeneous local conditions, material inhomogeneity, and uneven flow distribution across the single cell active area and in between the individual cells. The impact of the load level and air feed conditions on the performance was identified for individual single cells within a 10‐cell stack. Analysis of the current density...
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Revitalization of Residential Buildings Dating Back to the Late19th and Early 20th Century on the Example of “Willa Halina” in Sopot (Poland)
PublikacjaResidential buildings dating back to the late 19th and early 20th century constitute an important element of the urban composition of many European cities, often determining their overall spatial expression. These buildings often require revitalization and sometimes also reconstruction or extension. Such activities make it possible to restore historical buildings to their former glory, but also to create new architecture, inscribed...
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Laser Beam as a Precision Tool to Increase Fatigue Resistance in an Eyelet of Undercarriage Drag Strut
PublikacjaThe article contains the results of tests on a laser-processed eyelet of undercarriage drag strut to increase its fatigue strength. Laser processing concentrated on both sides around the hole of eye for connecting the undercarriage drag strut caused that the material in this area withstood more than twice the number of load cycles established for this material. In order to determine the reasons for the increase in fatigue strength,...
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Effective Permeability of Multi Air Gap Ferrite Core 3-Phase Medium Frequency Transformer in Isolated DC-DC Converters
PublikacjaThe magnetizing inductance of the medium frequency transformer (MFT) impacts the performance of the isolated dc-dc power converters. The ferrite material is considered for high power transformers but it requires an assembly of type “I” cores resulting in a multi air gap structure of the magnetic core. The authors claim that the multiple air gaps are randomly distributed and that the average air gap length is unpredictable at the...
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Validated HPTLC method for determination of ledol and alloaromadendrene in the essential oil fractions of Rhododendron tomentosum plants and in vitro cultures and bioautography for their activity screening
PublikacjaRhododendron tomentosum (Ledum palustre) is a bog shrub used in traditional medicine for treatment of respiratory and rheumatic diseases. Due to the large variability of the chemical composition of its essential oil, depending on the habitat, the in vitro cultures were established as the alternative source of the volatile fraction. There is a need to monitor a quality of the field grown as well as in vitro plant material, especially...
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Historical carpentry corner log joints—Numerical analysis within stochastic framework
PublikacjaThe paper presents the results of numerical analysis performed on historical, traditional carpentry corner logjoints of two basic topologies: the short-corner dovetail connection and the saddle notch connection. These types of carpentry joints are commonly used in currently preserved objects of wooden architecture. All connections have been modelled in pinewood, which has been defined in the Finite Element software MSC.Marc/Mentat...
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Leakage Current Measurements of Surge Arresters
PublikacjaThe paper presents the methods of assessing the technical condition of varistor surge arresters used in laboratory tests and in operation—performed without disconnecting the arresters from the network. The analysis of the diagnostic methods was supplemented with the results of the measurements of the leakage current of arresters coming directly from their production and used in the power industry. Among the available methods of...
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Potentiometric sensor containing set of ion selective electrodes with lipid modified membranes for quality assessment of tested non-alcoholic beverages
PublikacjaPotentiometric sensors may be a good tool for fast quality control of commercial drinks. In this work, such a sensor, containing a set of ion-selective electrodes with lipid-modified membranes (benzylhexadecyldimethylammonium chloride monohydrate, hexadecylamine, 1-dodecanol, elaidic acid, cholesterol) was used for discrimination and quality control of non-alcoholic beverages, mainly composed of sugar and citric acid. It was found...
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Time-Gating method with automatic calibration for accurate measurements of electrically small antenna radiation patterns in Non-Anechoic environments
PublikacjaNon-anechoic sites represent a cheap alternative to measurements of antennas in dedicated facilities. However, due to a high noise—from the external EM signal sources and multipath interferences—the quality of radiation patterns obtained in non-anechoic conditions is poor. The characteristics can be corrected using a time-gating method (TGM), which involves filtering of the noise based on temporal analysis of the measured signals....
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Comparing traffic intensity estimates employing passive acoustic radar and microwave Doppler radar sensor
PublikacjaThe purpose of our applied research project is to develop an autonomous road sign with built-in radar devices of our design. In this paper, we show that it is possible to calibrate the acoustic vector sensor so that it can be used to measure traffic volume and count the vehicles involved in the traffic through the analysis of the noise emitted by them. Signals obtained from a Doppler radar are used as a reference source. Although...
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Personal Brand Value and Social Media, the Top Football Players’ Case
PublikacjaPersonal branding valuation and social media usage are new and empirically unexplored areas of research. The aim of the presented study is to determine how social media performance and sentiment are related to the value of a personal brand. Based on an example of 100 most valuable football players, in reference to transfermarkt.com and the sentione.com (sentiment analysis), the author points out the strongest...
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Improving the quality of speech in the conditions of noise and interference
PublikacjaThe aim of the work is to present a method of intelligent modification of the speech signal with speech features expressed in noise, based on the Lombard effect. The recordings utilized sets of words and sentences as well as disturbing signals, i.e., pink noise and the so-called babble speech. Noise signal, calibrated to various levels at the speaker's ears, was played over two loudspeakers located 2 m away from the speaker. In...
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Moisture content during and after high- and normal-temperature drying processes of wood
PublikacjaThe aim of the article is to present the results of moisture content of wood during and after the high-temperature steam and air–steam mixture drying processes and after an open air-drying process. The knowledge of moisture content changes of wood in the process of its drying is one of the important parameters to economy drying process and to keep the quality of dried wood. Wood samples, namely, spruce (Picea abies K.) and beech...
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Design-Oriented Two-Stage Surrogate Modeling of Miniaturized Microstrip Circuits with Dimensionality Reduction
PublikacjaContemporary microwave design heavily relies on full-wave electromagnetic (EM) simulation tools. This is especially the case for miniaturized devices where EM cross-coupling effects cannot be adequately accounted for using equivalent network models. Unfortunately, EM analysis incurs considerable computational expenses, which becomes a bottleneck whenever multiple evaluations are required. Common simulation-based design tasks include...
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Numeryczna analiza możliwości zwiększenia efektywności grzewczej pompy ciepła, poprzez modyfikację skraplacza
PublikacjaW niniejszej pracy określono charakterystykę prostego modelu wymiennika ciepła bazującego na skraplaczu powietrznej pompy ciepła. Jest to helikoidalny rekuperator typu rura w rurze. Zaproponowano i poddano analizie numerycznej dwie metody intensyfikacji wymiany ciepła i zestawiono wyniki z modelem porównawczym. Zastosowane rozwiązania zwiększające strumień wymienianego ciepła spowodowały wzrost odbieranego przez wodę strumienia...
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Numerical analysis of pile installation effects in cohesive soils
PublikacjaIn this thesis the empirical equation for radial effective stress calculation after displacement pile installation and following consolidation phase has been proposed. The equation is based on the numerical studies performed with Updated Lagrangian, Arbitrary Lagrangian-Eulerian and Coupled Eulerian-Lagrangian formulations as well as the calibration procedure with database containing world-wide 30 pile static loading tests in cohesive...
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Mechanical, thermo-mechanical properties of epoxy/glass composites with submicron particles
PublikacjaIn this research the influence of submicron zinc oxide and silicon dioxide particles on mechanical, thermo-mechanical properties of epoxy matrix composites reinforced with glass fibres was investigated. Composites were fabricated using hand lay-up method. Materials contained 39-41 wt.% of glass fibres. The bending tests, dynamic mechanical analysis and tribological tests were performed on each group of composites and also for...
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Laser reflectance interferometry system with a 405 nm laser diode for in-situ measurement of CVD diamond thickness
PublikacjaIn situ monitoring of the thickness of thin diamond films during technological processes is important because it allows better control of deposition time and deeper understanding of deposition kinetics. One of the widely used techniques is laser reflectance interferometry (LRI) which enables non-contact measurement during CVD deposition. The authors have built a novel LRI system with a 405 nm laser diode which achieves better...
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The Application of Fluidic Sealing in Shrouded Gas Turbine Blades
PublikacjaThis paper presents a study conducted on a new gas turbine designed to limit leakage in the labyrinth seal. The slots in the fin are used to generate a bypass flow, which obstructs the flow in the gap above the fin. The method was tested numerically and experimentally beforehand using a simplified model without rotation or blade passages. In this paper, the validation of the method using a model of a turbine stage is shown. Reynolds-averaged...
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Computer Supported Analysis of the Human Body Surface Area
PublikacjaRecent scientific studies show the growing importance of the coefficients: BSA and TBSA, as an alternative to the widely used BMI. The relevant indicators are widely used in medicine, including such areas as: the treatment of burns, chemotherapy, dermatology and toxicology; as benchmarks when calculating doses of drugs and fluids. The particular problems concerning this subject are: the change of the reference parameter value which...
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Monitoring the BTEX Volatiles during 3D Printing with Acrylonitrile Butadiene Styrene (ABS) Using Electronic Nose and Proton Transfer Reaction Mass Spectrometry
PublikacjaWe describe a concept study in which the changes of concentration of benzene, toluene, ethylbenzene, and xylene (BTEX) compounds and styrene within a 3D printer enclosure during printing with different acrylonitrile butadiene styrene (ABS) filaments were monitored in real-time using a proton transfer reaction mass spectrometer and an electronic nose. The quantitative data on the concentration of the BTEX compounds, in particular...
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Evaluation of the prediction ability of air pollutants based on the electronic nose responses
PublikacjaElectronic noses are able to perform on-line measurements of the toxic volatile compounds in air. Due to their low cost and compact size they can be placed in the areas exposed to pollution, outside the laboratory. Those advantages, on the other side, force the need for development of the reliable sensors data analysis procedures. One of the most important issues connected with electronic noses is the lack of stability of the gas...
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Analysis of the state of preservation the historic arcaded houses in Vistula Delta listed in the National Inventory of Historical Monuments
PublikacjaHistoric arcaded houses are part of the material heritage of the Vistula Delta. Unfortunately, their number is decreasing year by year. The article is the result of a query of available sources and field research carried out by the author in 2015-2020. The paper presents the current state of preservation the historic arcaded houses in Vistula Delta listed in the National Inventory of Historical Monuments. Criteria for the selection...
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Uncertainty assessment of ultimate strength of corroded stiffened plates subjected to different maintenance actions
PublikacjaThe study deals with the uncertainty assessment of different governing factors related to the ultimate strength of the corroded stiffened plates. The load-carrying capacity is predicted with the use of the nonlinear Finite Element Method. The most influencing governing factors in the non-linear FE analysis, such as material properties and initial imperfections are modeled and analysed as stochastic variables. The ultimate strength...
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The study on possibilities of recovery non-magnetic fraction by utilisation the magnetic separation technology in conditions of KGHM Polska Miedz S.A. division of concentrators = Próby odzysku frakcji niemagnetycznej metodą separacji magnetycznej w warunkach KGHM Polska Miedź S.A. Oddział Zakłady Wzbogacania Rud
PublikacjaW referacie przybliżono wyniki badań prowadzonych w kierunku określenia możliwości odzysku frakcji niemagnetycznej i słabomagnetycznej ze strumieni materiałowych O/ZWR, poprzez wykorzystanie metody separacji magnetycznej. Przeprowadzony cykl badawczy obejmował analizę występowania frakcji magnetycznej i związanej z nią frakcji niemagnetycznej w obiegach technologicznych w Rejonie ZWR Lubin, oraz możliwości ich odzysku. Uzyskane...
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Comparative Analysis of Laboratory-Made and Industrial-Made Sewage Sludge Ash: Implications for Effective Management Strategy Development
Publikacjafirst_pageDownload PDFsettingsOrder Article Reprints Open AccessArticle Comparative Analysis of Laboratory-Made and Industrial-Made Sewage Sludge Ash: Implications for Effective Management Strategy Development by Bartłomiej Michał Cieślik 1,*ORCID,Oskar Ronda 1ORCID,Elżbieta Grządka 2ORCID,Jolanta Orzeł 2 andJustyna Płotka-Wasylka 1 1 Department of Analytical Chemistry, Faculty of Chemistry, Gdańsk University of Technology, Gabriela...
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A new method of presosns identification based on comparative analysis of 3D face models
PublikacjaThe article presents the use of modern close range photogrammetry for possessing highly accurate 3D models of the human face (including the ears). Modern methods used to obtain precise data describing the construction of a human face, and even the whole human body, should allow to get finished measurement material in a very short time. Those features belong to the optical scanning technology. Comparative analysis of models of the...
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Analysis of the Environmental Impact of the Hull Construction of a Small Vessel Based on LCA
PublikacjaIn recent years, issues related to the impact of human activity on the natural environment have become pressing, and the challenge of global warming necessitates immediate action. To support environmental protection efforts, it has become imperative to adopt a broader perspective when evaluating various products and systems. A valuable tool for such assessments is a life cycle assessment (LCA), which enables a comprehensive analysis...
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A selectively reduced degree basis for efficient mixed nonlinear isogeometric beam formulations with extensible directors
PublikacjaThe effect of higher order continuity in the solution field by using NURBS basis function in isogeometric analysis (IGA) is investigated for an efficient mixed finite element formulation for elastostatic beams. It is based on the Hu–Washizu variational principle considering geometrical and material nonlinearities. Here we present a reduced degree of basis functions for the additional fields of the stress resultants and strains...
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Wpływ struktur wsparcia na efektywność nauczania języka pisanego w środowisku e-learningowym
PublikacjaThe process of knowledge and language skills development during an online course can be very effective if student engagement in learning is achieved. This can be attained by introducing general and specific support mechanisms prior to the commencement of the course and during it. The former relates to the technological aspect, that is to familiarizing students with the functionalities of the virtual learning environment they will...
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Olfactory receptor-based biosensors as potential future tools in medical diagnosis
PublikacjaThe detection of biomarkers is the future of non-invasive medical diagnosis and screening. Discovery and identification of reliable disease specific volatile organic compounds is dependent on repeatable, accurate analysis of trace level gaseous analytes mainly in breath samples. Natural variety of the olfactory systems and the compounds capable of gas molecules binding creates wide possibilities of acquisition and implementation...
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Pharmaceuticals and another groups of emerging contaminants: Occurrence and sources in Admiralty Bay (King George Island, Maritime Antarctica)
PublikacjaEveryday live activities may introduce a wide range of chemicals into wastewater systems. In this study presence of selected types of pharmaceuticals from cardiovascular system group, nervous and muscolo-skeleton system group, antimicrobial agents, genitourinary and sex hormones were tested in the wastewater from H. Arctowski Antarctic station. Moreover, the receiver of discharged wastewater (Admiralty Bay) were also studied. Considering...
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Innowacyjny moduł ultradźwiękowy systemu monitoringu technicznego mostu podwieszonego w Rzeszowie
PublikacjaW artykule przedstawiono system monitoringu technicznego konstrukcji mostu podwieszonego nad rzeką Wisłok. System będzie wyposażony w dodatkowy moduł ultradźwiękowy umożliwiający śledzenie degradacji mechanicznej betonu w pylonie mostu. Wczesne wykrywanie stref mikropęknięć, przed pojawieniem się widocznych rys, umożliwia monitorowanie amplitud propagującej fali ultradźwiękowej oraz analizę sygnałów w dziedzinie częstotliwości.
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Konkurencyjność w handlu usługami wybranych krajów Europy Środkowo-Wschodniej
PublikacjaCelem artykułu jest ocena pozycji konkurencyjnej w handlu usługami wybranych krajów Europy Środkowo-Wschodniej – Czech, Estonii, Litwy, Łotwy, Polski, Słowacji oraz Węgier na tle gospodarki światowej. Dane wykorzystane do analizy pochodzą z bazy danych WIOD i obejmują lata 1995 – 2011. Podstawą oceny pozycji konkurencyjnej jest wskaźnik RCA obliczony na podstawie krajowej wartości dodanej oraz na podstawie eksportu brutto. Źródłem...
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Influence of hydrochloric acid concentration and type of nitrogen source on the electrochemical performance of TiO2/N-MoS2 for energy storage applications
PublikacjaIn this work, nitrogen-doped molybdenum sulfide was directly deposited on titanium dioxide nanotubes substrate (TiO2/N-MoS2) during hydrothermal synthesis. The study focuses on the influence of hydrochloric acid concentration used for the synthesis, with the results indicating its essential role in thioacetamide hydrolysis and thus in the effectiveness of the N-MoS2 deposition. The electrode material itself is characterized by...
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Investigation on stability of mountainous EUPOS sites’ coordinates
PublikacjaThe paper concerns analysis of solutions obtained during common processing of data from GNSS permanent stations situated on mountainous terrain: the Western Carpathians, the Sudetes Mountains and adjacent areas. As the outcome daily and weekly solutions (ellipsoidal coordinates) of forty Polish, Czech, Slovak, Ukrainian and German sites were obtained. Weekly solutions were used to determine velocity field and vertical movements,...
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The Economic Legacy of Mega Sporting Events. The Impact of Hosting European Olympic Games on GDP Growth Through Infrastructure Development
PublikacjaIntroduction. The positive legacy of the Olympics is often cited by the International Olympic Committee and national or-ganizers. Some scholars, however, question an uncritical approach to an exclusively positive economic legacy. The aim of this study is to evaluate the impact of hosting the Olympics on infrastructure development, with a potential impact on economic growth in the form of Gross Domestic Product (GDP) in three phases...
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M-integral for finite anti-plane shear of a nonlinear elastic matrix with rigid inclusions
PublikacjaThe path-independent M-integral plays an important role in analysis of solids with inhomogeneities. However, the available applications are almost limited to linear-elastic or physically non-linear power law type materials under the assumption of infinitesimal strains. In this paper we formulate the M-integral for a class of hyperelastic solids undergoing finite anti-plane shear deformation. As an application we consider the problem...