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Comparison of oral-health-related quality of life in patients in the short- and long-term period following lower-facial injury and fractures – preliminary report
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On finite element modelling of architectural fabrics for hanging roofs
PublikacjaArtykuł dotyczy modelowania konstytutywnego i identyfikacji parametrów materiałowych dla tkanin technicznych powszechnie stosowanych w konstrukcjach membranowo-cięgnowych. Autorzy przedstawiają krótką charakterystyke modeli stosowanych w opisie zachowania sie tkanin technicznych. Opisano metodę do idetyfikacji nieliniowo-sprężystych właściwości tkanin technicznych. Dodatkowo dokonao porówania wyników z prób jednoosiowego rozciągania...
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Second-order differential equations with deviating arguments
PublikacjaPodane zostały warunki dostateczne na istnienie kwazi-rozwiązań oraz na istnienie jedynego rozwiązania dla równań różniczkowych rzędu drugiego z warunkami brzegowymi i odchylonymi argumentami. Otrzymane wyniki zilustrowano przykładami i wykresami.
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Eveningness and its possibility of predicting burnout symptoms among physicians and nurses – preliminary results
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Constructional properties of polycarbonate plates for EURO 2012 Gdansk stadium
PublikacjaPrzedstawiono wyniki badań doświadczalnych dla płyt z poliwęglanu litego, które miały zostać wykorzystane jako materiał konstrukcyjno-osłonowy stadionu piłkarskiego na mistrzostwa Euro 2012 w Gdańsku. Zidentyfikowano moduł Younga oraz Poissona, wykonano próby cykliczne oraz pełzania. Właściwości mechaniczne poliwęglanu litego oceniono jako dobre, choć obawy budzą mikrorysy pojawiające się podczas badań w strukturze materiału.
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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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Toolgraph Design of Optimal and Feasible Control Strategies for Time-Varying Dynamical Systems
PublikacjaArtykuł prezentuje nową metodę projektowania optymalnych i realizowanych strategii sterowania dla wariantnych procesów dynamicznych. Centralnym ośrodkiem i narzędziem tej metody jest struktura grafu przepływowego reprezentująca istotne właściwości autonomicznej dynamiki danego procesu w przestrzeni czasowo-stanowej, składającej się z elementarnych segmentów. Strukturę tę nazywamy grafem narzędziowym przestrzeni czasowo-stanowej....
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Periodic Properties of 1D FE Discrete Models in High Frequency Dynamics
PublikacjaFinite element discrete models of various engineering 1D structures may be considered as structures of certain periodic characteristics. The source of this periodicity comes from the discontinuity of stress/strain field between the elements. This behaviour remains unnoticeable, when low frequency dynamics of these structures is investigated. At high frequency regimes, however, its influence may be strong enough to dominate calculated...
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Hearing and stomatognathic system: Searching for a link
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Identification of inertia, damping and stiffness parameters for low pressure steam turbine framework.
PublikacjaW pracy przedstawiono metodę identyfikacji masy tłumienia i sztywności kadłuba części niskoprężnej turbiny parowej 200MW.
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Youth attitude to entrepreneurship in Eastern and Central European countries: Gender aspect
PublikacjaCurrent business conditions pose new challenges to youth entrepreneurship, which is a significant component of countries’ economic growth. In addition, Generation Z differs from previous generations and requires new approaches. In this context, a comprehensive study of the peculiarities and various aspects of youth entrepreneurship development is highly-demanded and relevant. Furthermore, the lower representation of women among...
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The effectiveness of financial and economic regulation of land relations in the context of stimulating entrepreneurial activity in the regions of Ukraine
PublikacjaSolving the problem of enhancing the efficiency of the financial and economic regulation of land relations contributes to the development of entrepreneurship in Ukraine. The purpose of the paper is to determine new incentives for encouraging entrepreneurial activity by increasing the efficiency of the financial and economic regulation of land relations by local governments. The study is based on applying the method for predicting...
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Entrepreneurial competencies and intentions among students of technical universities
PublikacjaThe study investigates the entrepreneurial competencies and intentions of students. Their formation is a requirement of modern times. The question arises whether students of modern technical universities get entrepreneurial competencies and whether they transform these competencies into their entrepreneurial intentions. More than 3.6 thousand students from six technical universities from Poland, Ukraine, Latvia, Bulgaria, and Lithuania...
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Using similar classification tasks in feature extractor learning
PublikacjaThe article presents and experimentally verify the idea of automatic construction of feature extractors in classification problems. The extractors are created by genetic programming techniques using classification examples taken from other problems then the problem under consideration.
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Method of lines for nonlinear first order partial functional differential equations.
PublikacjaClassical solutions of initial problems for nonlinear functional differential equations of Hamilton--Jacobi type are approximated by solutions of associated differential difference systems. A method of quasilinearization is adopted. Sufficient conditions for the convergence of the method of lines and error estimates for approximate solutions are given. Nonlinear estimates of the Perron type with respect to functional variables...
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Method of lines for Hamilton-Jacobi functional differential equations.
PublikacjaInitial boundary value problems for nonlinear first order partial functional differential equations are transformed by discretization in space variables into systems of ordinary functional differential equations. A method of quasi linearization is adopted. Suffcient conditions for the convergence of the method of lines and error estimates for approximate solutions are presented. The proof of the stability of the diffrential difference...
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Scattering and Propagation Analysis for the Multilayered Structures Based on Field Matching Technique
PublikacjaA semi-analytical method is employed to the analysis of scattering and guiding problems in multilayer dielectric structures. The approach allows to investigate objects with arbitrary convex cross section and is based on the direct field matching technique involving the usage of the field projection at the boundary on a fixed set of orthogonal basis functions. For the scattering problems the scattered field in the far zone is calculated...
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On the problem of optimised allocation of water quality sensors and actuators in DWDS
PublikacjaThe problems of water quality sensors and actuators placement in drinking water distribution systems (DWDSs) are addressed as separate, primarily. However, against the background of control systems theory, the nature of DWDSs dynamics indicates that these both problems are interdependent and impact the design of related water quality monitoring and control structures and algorithms. The research work presented in this paper is...
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Active Kriging-based conjugate first-order reliability method for highly efficient structural reliability analysis using resample strategy
PublikacjaEfficient structural reliability analysis method is crucial to solving reliability analysis of complex structural problems. High-computational cost and low-failure probability problems greatly limit the efficiency in structural reliability analysis problems, causing the safety and reliability of the structure to be questioned. In this work, a highly efficient structural reliability analysis method coupling active Kriging algorithm...
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Modernity and postmodernity in architectural education
PublikacjaThe purpose of this article is to present a philosophical education strategy for architecture and interior architecture faculties. The approach is the result of trial and error in lectures and debates with students of philosophical courses in these fields. The presented article is not a result of empirical research, but rather a report on the problems encountered and proposals for their solution. The experience gained from conducting...
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Sacral sound-engineering
PublikacjaOrganologic and campanologic acoustical problems due to applications to sacral objects are characterized on ground of numerous reviewed publications and engineering reports. Participations of several involved research centres, mostly Polish, at solving these problems are evaluated. Some desirable future developments are indicated. Appendices bring examples of documentation on selected investigated objects.
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Barriers of Cross-cultural Interactions According to the Research Findings
PublikacjaThe aim of this article is to label major cultural barriers and to present results of empiricalfindings referring to barriers to intercultural interactions in foreign subsidiaries oftransnational corporations (TNCs). The qualitative research was conducted in TNCs'foreign subsidiaries operating in Poland in the winter of 2009/2010. The articledescribes how the respondents perceived the problems in cooperation with foreigners,defines...
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Practical aspects of design and operation of amphibious craft for rescue purposes
PublikacjaThe paper presents the selected problems of design and operation of amphibious craft for rescue purposes. The result of research on the amphibious rescue units allowed formulating the general conclusions with respect to the proper selection of the main design parameters, program of model tests and full scale trials for the amphibious craft. The most important design problems related to the water characteristics are presents and...
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Usefulness of the voltamperometric method for assessment of the purity of soil
PublikacjaThis paper presents a voltammetric analysis of soil. It shows that the voltammetry is a useful method for the assessment of soil contaminated with heavy metal ions. There are two major problems with voltammetry analysis: the diffusion coefficient and the measurement system. The paper contains a short literature study of mathematical equations and a study of differences between soil and water measurements. Suggestions of the solution...
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Portable raman spectrometer with two excitation wavelengths
PublikacjaSelected problems of development of a portable Raman spectrometer having small size, reduced power consumption and robust construction are shown. The device dedicated for semiskilled personnel uses two lasers: 785nm and 355nm. Results of preliminary tests are presented. Also data processing procedures as well as problems referred to Raman signals acquisition through packages and influence of interfering signals are discussed.
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Monotone iterative method to second order differential equations with deviating arguments involving Stieltjes integral boundary conditions
PublikacjaWe use a monotone iterative method for second order differential equations with deviating arguments and boundary conditions involving Stieltjes integrals. We establish sufficient conditions which guarantee that such problems have extremal solutions in the corresponding region bounded by lower and upper solutions. We also discuss the situation when problems have coupled quasi-solutions. We illustrate our results by three examples.
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Engineering Analysis with ANSYS Software Second Edition
PublikacjaThe best way to learn complex systems is by means of hands-on experience. With an innovative and clear tutorial based approach, this powerful book provides a comprehensive introduction to the fundamental areas of engineering analysis needed on research or commercial engineering projects. With its detailed step-by-step explanations and sample problems, this book will develop the reader's understanding of FEA and their ability to...
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Positive solutions for second order impulsive differential equations involving Stieltjes integral conditions
PublikacjaIn this paper we investigate integral boundary value problems for fourth order differentialequations with deviating arguments.Wediscuss our problem both for advanced or delayedarguments. We establish sufficient conditions under which such problems have positivesolutions. To obtain the existence of multiple (at least three) positive solutions, we use afixed point theorem due to Avery and Peterson. An example is also included to...
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The Dynamical Projectors Method Hydro and Electrodynamics
PublikacjaThe dynamical projectors method proves to reduce a multicomponent problem to the simplest one-component problem with its solution determined by specific initial or boundary conditions. Its universality and application in many different physical problems make it particularly useful in hydrodynamics, electrodynamics, plasma physics, and boundary layer problems. A great variety of underlying mechanisms are included making this book...
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Stereoscopy in Graphics APIs for CAVE Applications
PublikacjaThe paper compares the advantages and disadvantages of a variety of Graphics Application Programming Interfaces (APIs) from the perspective of obtaining stereoscopy in applications written for a CAVE virtual reality environment. A number of problems have been diagnosed and an attempt has been made to solve them using OpenGL, DirectX 11 and 12, Vulkan, as well as the Unity Engine which can internally use DirectX, OpenGL and Vulkan,...
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The use of innovative application in creating new marketing space for cultural and entertainment events in the local market
PublikacjaThe following article describes the problems concerning marketing of mass events in the local market and potential solutions. In the first part the barriers that occur in communication between the organizers and the articipants are defined. In the process of identifying problems the results of research conducted for the needs article were used. In following sections the solution with use of Smartphone app is shown. The features that...
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THE IPV4 TO IPV6 MIGRATION OF APPLICATIONS AND SERVICE
PublikacjaThis article presents the problems related to IPv4 to IPv6 migration of applications supporting network services. It summarizes the needs of executing such migration. It shows the basic problems of automating the migration process, having defined the basic terms, i.e.: a network service, a network application. It shows a sample implementation of the automation of the migration process between IP technologies for selected network...
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Offshoring and outsourcing in Visegrad countries, Advantages and disadvantages.
PublikacjaOutsourcing and offshoring are getting more and more popular in the “new EU” coun-tries. They constitute very attractive venues for more developed EU countries to outsource or offshore their business activities. Authors of the article have investigated the advantages and disadvantages of locating outsourcing activities in each of the Visegrad (V4) countries. The authors have studied macroeconomic factors based on the reports of...
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Analysis of Failures of High Speed Shaft Bearing System in a Wind Turbine
PublikacjaDuring the operation of wind turbines with gearbox of traditional configuration, consisting of one planetary stage and two helical stages high failure rate of high speed shaft bearings is observed. Such a high failures frequency is not reflected in the results of standard calculations of bearing durability. Most probably it can be attributed to atypical failure mechanism. The authors studied problems in 1.5 MW wind turbines of...
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A higher order shell element for wave propagation in isotropic shell structures
PublikacjaThe presents the new multi mode higher order shell element for wave propagation problems in shell structures.
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Electromagnetic Simulations with 3D FEM and Intel Optane Persistent Memory
PublikacjaAbstract—Intel Optane persistent memory has the potential to induce a change in how high-performance calculations requiring a large system memory capacity are conducted. This article presents what this change may look like in the case of factorization of large sparse matrices describing electromagnetic problems arising in the 3D FEM analysis of passive highfrequency components. In numerical tests, the Intel oneAPI MKL PARDISO was...
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Control strategies and comparison of the Dynamic Voltage Restorer
PublikacjaThis paper focuses on a selection problems of mitigation of the voltage disturbance by of the Dynamic Voltage Restorers (DVR’s). In short form presented and discussed are the basis of different control strategies of the DVR. The main emphasis is placed on application of modern power electronic devices. Authors of this paper in particular occupy oneself with analysis of the power rating of the typically DVR topologies. These problems...
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Photoelectrochemical characterization of nitrogen-modified TiO2
PublikacjaTrzy próbki tlenku tytanu(IV) o różnej zawartości azotu i różnych właściwościach fotokatalitycznych zostały wybrane do charakterystyki fotoelektrochemicznej. Efektem finalnym jest określenie położenia pasma wzbronionego i pasma przewodzenia w otrzymanych półprzewodnikach.
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Selective transport of Pb(II) across polymer inclusion membrane using imidazole azocrown ethers as carriers.
PublikacjaZbadano selektywność transportu jonów ołowiu(II) z równomolowych roztworów jonów Zn(II), Cd(II) i Pb(II) przez polimerowe membrany inkluzyjne (PIM) zawierające imidazolowe etery azokoronowe.Wykazano, że polimerowe membrany inkluzyjne z imidazolowymi azokoronami wykazują dużą stabilność, zależną w dużym stopniu od rodzaju jonoforu.
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Imidazolium ionic liquids in mineral processing
PublikacjaImidazoliowe ciecze jonowe (ILs) stanowią nową klasę związków o szerokich możliwościach przemysłowego zastosowania. Z przeglądu dostępnej literatury wynika, że ILs mogłyby zostać wykorzystane do odzysku i oczyszczania metali ze środowiska wodnego oraz rud w procesach ługowania, ekstarkcji rozpuszczalnikowej oraz w procesach elektrochemicznych. Pochodne imidazoliowe mogą być wykorzystywane zarówno jako rozpuszczalniki jak i aktywne...
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An investigation on wetting of porous materials
PublikacjaPośrednie metody oceny zdolności zwilŜania drobnych cząstek lub materiałów porowatych wymagają wyboru cieczy odniesienia, dla której kąt zwilŜania jest równy zeru. W badaniach własnych zastosowanometodę wzniesienia kapilarnego oraz metodę flotacji filmowej dla układów mikrokulki szklane-woda i mikrokulki szklane-dekan. Uzyskane dane dla cieczy odniesienia i dla cieczy badanej wprowadzano dozmodyfikowanego równania Washburn'a i...
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Transport of lead across polymer inclusion membrane with p-tert-butylkalix[4]arene derivative
PublikacjaOpisane zostały ułatwienia w transporcie jonów ołowiu (II) przez polimerową membranę inkluzyjną (PIMs),która składała się z trój octanu celulozy jako polimerowego suportu, eteru o-nitrofenylooktylu jako plastyfikatora i 25,26,27,28, tetra-(N-hydroksy-N-metylokarbonylo metoksy)-p-tert-butylokaliks[4]arenu jako nośnika jonów. Polimerowa membrana inkluzyjna została scharakteryzowana przy pomocy mikroskopu sił atomowych (AFM). Otrzymane...
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Potential application of ionic liquids in aluminium production - economical and ecological assessment
PublikacjaTechnologia wytwarzania aluminium stosowana na skale przemysłową oparta jest na elektrodepozycji w ciekłym kriolicie i nosi nazwę procesu Hall-Heroult'a. Technologia ta wymaga wysokich nakładów energii elektrycznej, charakteryzuje się ponadto, szeroko udokumentowanym, negatywnym wpływem na środowisko naturalne. Produkcja aluminium możliwa jest również metodą alternatywną poprzez elektrodepozycję a mieszaniny cieczy jonowych w temperaturze...
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Changes in rheological properties during anaerobic digestion of activated sludge
PublikacjaWykonane pomiary właściwości reologicznych osadwo nadmiernych poddawanych procesowi dezintegracji mechanicznej wskazują na znaczny spadek lepkości sięgający 60%. Wraz ze stopniem dezintegracji rosły również właściwości pseudoplastyczne oraz malała granica płynięcia. Podobnie istotne zmiany właściwosci reologicznych nastepowały w osadach poddawanych fermentacji metanowej.
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Efficiency of deep bed filtration in treatment of swimming pool water
PublikacjaPrzebadano efektywność filtracji wody w filtrach ze złożem żwirowo-piaskowym w instalacji basenu rehabilitacyjnego. Obok analizy instrumentalnej wody, w badaniach uwzględniono rozkład wielkości cząstek i analizę termiczną osadu zgromadzonego w złożu piaskowym filtrów wgłębnych i usuwanego podczas płukania.
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Photocatalytic activity and surface properties of carbon-doped titanium dioxide
PublikacjaTiO2 domieszkowany węglem otrzymano poprzez hydrolizę izopropanolanu tytanu(IV) i kalcynację w 350ºC w atmosferze powietrza przez 2h. Przeprowadzone badania wykazały, że fenol (0.21 mM) jest efektywnie degradowany w fazie wodnej, w obecności otrzymanego fotokatalizatora oraz światła z zakresu widzialnego (λ>400 nm). Pole powierzchni właściwej otrzymanego C-TiO2 wynosiło około 127 m2/g, fotokatalizator absorbuje światło z zakresu...
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Au-RE-TiO2 nanocomposites: Surface characteristics and photoactivity
PublikacjaThe photocatalysts based on TiO2 co-doped with rare earth metal (RE) and gold nanoparticles have been prepared using a sol-gel method and followed by gold reduction. Specific surface areas of the modified photocatalysts were calculated by the Brunauer-Emmett-Teller method (BET). Diffuse reflectance spectra of the obtained photocatalysts were recorded in a UV-Vis spectrophotometer (DRS UV-Vis). The influence of the type of rare...
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NOBLE METAL MODIFIED TiO2 FOR PHOTOCATALYTIC AIR PURIFICATION
PublikacjaTiO2 was surface modified with silver, gold, palladium and platinum ion clusters to improve its photocatalytic activity. The effect of metal content, the kind of dopant used during preparation procedure on the photoactivity were investigated. in toluene removal which was used as a model volatile organic compound. Toluene, at the concentration of about 100 ppm, was irradiated over noble metal modified TiO2 using light-emitting diodes...
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Radioactivity of drilling cuttings from shale resources of the Lower Paleozoic Baltic Basin, Poland
PublikacjaFractionated drilling wastes originating from shale gas exploration in the Baltic Basin in Pomerania were subjected to the measurements of mean activity concentrations of naturally occurring radioactive materials (NORMs).To better understand rock structure and texture, the X-ray diffraction analysis (XRD) and scanning electron microscopy(SEM) observation were used. To compare activity concentration of radionuclides in bulk wastes...
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Wettability of shale rock as an indicator of fracturing fluid composition
PublikacjaShales have become one of the main unconventional gas resources in the world. However, physicochemical properties of rocks are still at the center of research. There have been conducted major researches in wettability of shales by fluids and advances in understanding and control of shale rock wettability. Also influence of interfacial phenomena on a production capacity of reservoirs have been made. The aim of this study is to find...