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Wyniki wyszukiwania dla: SFEM
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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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Calculation of Resonance in Planar and Cylindrical Microstrip Structures Using a Hybrid Technique
PublikacjaA hybrid technique was employed for the analysis of the resonance frequency of thin planar and cylindrical microstrip structures with the patches of arbitrary geometry. The proposed technique utilizes a combination of Galerkin’s moment method and a finite-element method (FEM). In this approach, an FEM is adopted to calculate the patch surface current densities, and a method of moments is utilized to calculate the resonance frequencies...
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Dewetting of silver films detected by XPS method
Dane BadawczeDewetting of silver thin films was detected by XPS method. Thin metallic films were deposited by magnetron sputtering method. Formation of nanostructures , as a result of thermal annealing, was confirmed by SEM microscope. For comparision three samples were measured. Bulg gold, as-deposited silver film with thickness of 3 nm and nanostructures.
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Theoretical analysis of the cable-stayed bridge over brda river in Bydgoszcz
PublikacjaThe topic of this article is the numerical analysis carried out for the cable-stayed tram (road) bridge over Brda river in Bydgoszcz. The goal of numerical studies was the verification of project assumptions and construction solutions elaborated by the autonomous team. The bridge calculations were conducted on three independent FEM models The internal forces and the elements effort under different loading schemes were examined....
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Numerical Modelling of Structures with Uncertainties
PublikacjaThe nature of environmental interactions, as well as large dimensions and complex structure of marine offshore objects, make designing, building and operation of these objects a great challenge. This is the reason why a vast majority of investment cases of this type include structural analysis, performed using scaled laboratory models and complemented by extended computer simulations. The present paper focuses on FEM modelling...
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Wyjaśnienie przyczyn korozji rur kotła, wytwornicy pary technologicznej instalacji Olefiny
PublikacjaWykonano badania przyczyn korozji rurek wytwornicy pary instalacji Olefiny. Przeprowadzono badania metalograficzne oraz SEM i EDX produktów korozji
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SEM/EDX data of (Cr,Fe,Mn,Co,Ni)3O4 High-entropy spinel oxide thin films deposited on amorphous SiO2 substrate by spray pyrolysis techniqe
Dane BadawczeThis Data set include SEM and EDX results of (Mn,Co,Fe,Ni,Cr)3O4 high-entropy spinel oxide prepared in the form of a ~ 500 nm thin film utilising a facile spray pyrolysis technique. The structural and electrical properties of the layers were characterised after exposure to temperatures in the range of 400–900 ◦C. The as-deposited layers were amorphous,...
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Miasto nocą: zaburzenia snu a praca zmianowa i stres zawodowy wśród policjantów
PublikacjaStreszczenie. Jedną z miar subiektywnej jakości życia jest dobry sen. Cebulowa teoria szczęścia postuluje zależność pomiędzy dobrostanami cząstkowymi. Celem studium była ocena zaburzeń snu wśród policjantów z miejskich komisariatów Policji w zależności od cech pracy (stres zawodowy) i jej organizacji (zmianowość). Rezultaty pokazały, że większe problemy ze snem mieli policjanci pracujący wyłącznie na zmianach dziennych niż pracujący...
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The influence of stainless steels microstructure evolution on the mechanical properties of pressure installation elements
PublikacjaIn this paper results of FEM analysis performed for pipe and 90o elbow, made of super duplex stainless steel, after precipitation of sigma phase (s), were presented. Heat treatment conditions simulate accidental overheating that can occur in nuclear installations after cooling circulation fails. For initial and modified microstructure tensile test was performed and numerical description of work hardening curves was done. Verification...
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Determination of Failure Causes of a Steam Turbine Casing
PublikacjaThe paper presents results of research and failure analysis undertaken to determine failure causes of a steam turbine casing. After 130,000 hours of service the crack in a outer shell of the turbine casing was found. The inner shell of the casing was made of cast steel grade G21CrMoV5-7, and the outer shell of grade G20CrMo4-5. Following research were performed in order to determine causes of the casing failure: chemical analysis;...
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The influence of stainless steels microstructure evolution on the mechanical properties of pressure installation elements
PublikacjaIn this paper results of FEM analysis performed for pipe and 90o elbow, made of super duplex stainless steel, after precipitation of sigma phase (),were presented. Heat treatment conditions simulate accidental overheating that can occur in nuclear installations after cooling circulation fails. For initial and modified microstructure tensile test was performed and numerical description of work hardening curves was done. Verification...
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Integration and Dependency in Software Lifecycle Based on Jazz Platform
PublikacjaSoftware delivery organizations are being asked to meet goals that seem mutually exclusive. Teams are asked to increase product quality, accelerate time to market, and meet increasing mandates from regulatory bodies. As software solutions and software development environments become rapidly more complex. Many business drivers compound these challlenges.
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Numerical Analysis of Mice Carotid Arteries’ Response Emphasizing the Importance of Material Law Constants’ Validation
PublikacjaIn this paper, a detailed validation of the passive material properties of mice carotid arteries and constants of the Fung and Holzapfel hyperelastic material laws is conducted by means of static nonlinear FEM analyses. The response of the carotid arteries in an inflation test is studied here for the following mouse models: wild-type, mdx, sgcd−/−, Eln+/+, Eln+/−, Fbln5+/+, and Fbln5−/−. All FEM computations are conducted on models...
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Search engine marketing jako istotne narzędzie komunikacji marketingowej
PublikacjaKomunikacja marketingowa firmy w Internecie musi uwzględniać tzw. marketing w wyszukiwarkach internetowych (SEM). O efektywnej obecności przedsiębiorstwa w Sieci można mówić, gdy łatwo znaleźć serwis internetowy uwzględniając organiczne wyniki wyszukiwania wyszukiwarek, reklamy typu pay-per-click, optymalizację kluczowych fraz, istotność linków przychodzących (zewnętrznych) oraz wartość zamieszczonych treści. Każdy element projektu...
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Analizy wpływu współpracy blach poszycia z konstrukcją nośną na wartości sił wewnętrznych i przemieszczeń hali stalowej.
PublikacjaW niniejszej pracy, wykorzystując możliwości programu Dlubal RFEM 5.04, przedstawiono efekty uwzględniania współpracy konstrukcji nośnej hali z poszyciem wykonanym z blach trapezowych. Przeprowadzono analizy obliczeniowe kilku wariantów modelu 3D przykładowej hali stalowej. Wyniki obliczeń oraz wnioski zestawiono w tablicach.
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Influence of bio-polyols with different molecular weight on properites of PUR-PIR foams
Dane BadawczeThis work attempts to validate the possibility of replacing petrochemical polyols with previously synthesized bio-polyols and their impact on the structure and properties of rigid polyurethane-polyisocyanurate (PUR-PIR). The influence of bio-polyols addition on foam properties was investigated by mechanical testing, Fourier transform infrared spectroscopy...
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Smooth Particle Hydrodynamics (SPH) approach in simulating large penetration into soil
PublikacjaA study of Smooth Particle Hydrodynamics (SPH) approach for predicting large soil deformation is presented. Theoretical basics of SPH method, including the equations governing, discussion of the importance of smoothing function length, contact formulation, boundary treatment and finally utilization in hydrocodes simulations are presented. An application of SPH to a real case of large penetrations (crater creating) into soil caused...
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Equivalent 4-node enhanced assumed strain and hybrid stress shell elements in 6-parameter theory
PublikacjaWe discuss the equivalence of semi-enhanced assumed strain (EAS) and semi-hybrid stress (SEM) shell finite elements. We use the general nonlinear 6-field shell theory with kinematics composed of generalized displacements composed of the translation field and the rotation field. Due to the presence of rotation tensor the elements have naturally six nodal engineering degrees of freedom. We propose interpolation for a strain field...
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A constitutive law for concrete with smooth transition from continuous into discontinuous cracks’ description
PublikacjaPaper presents a constitutive model for concrete that combines a continuous and discontinuous crack’s description to simulate the concrete under tensile dominated loads. In a continuum regime, two different constitutive laws were used. First, a plasticity model with the Rankine failure criterion and an associated flow rule was used. Second, a constitutive law based on isotropic damage mechanics was formulated. Both model alternatives...
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Influence of the femoral offset on the muscles passive resistance in total hip arthroplasty
PublikacjaBackground Soft tissue tension is treated as a crucial factor influencing the post-THA dislocation. The femoral offset is regarded as one of the major parameters responsible for the stabilization of the prosthesis. It is unclear which soft tissue is mostly affected by the offset changes. Methods A finite element model of the hip was created. The model comprised muscles, bones, a stem, the acetabular component and a liner. The muscles...
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Runner bean (Phaseolus coccineus) histological cross section observations of stems, leaves, and roots using light microscope
Dane BadawczeThis data set contains images of root crown, root, stem, and leaf cross-sections of runner bean (Phaseolus coccineus). Runner bean seedlings (3-5 cm) were planted on soil amended with poultry (chicken) manure biochars pyrolized at various temperatures (400, 500, and 600 C degrees). Three different poultry manure biochar materials (450, 500, and 600°C)...
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Use of structural equation modeling in quantitative research in the field of management and economics: A bibliometric analysis in the systematic literature review
PublikacjaPURPOSE: This paper aims to provide a comprehensive review of scholarly research focusing on using quantitative methods and particularly structural equation modeling (SEM) in management and economics studies, as well as provide a bibliometric agenda including the time horizon of individual publications, the highest citation rate, geographic and industry areas, methodological context, and keywords. METHODOLOGY: A systematic literature...
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On the influence of shell element properties on the response of car model in crash test
PublikacjaIt goes without saying that numerical simulations play important role in the modern engineering practice. Contemporary CAD environments combined with FEM solvers, along with computer power of modern processors, give the engineer fast and efficient tool. Ultimately, however it is the user alone who is responsible for the correctness of the results. As long as the FEM calculations remain in the sphere of academic exercise, the inevitable...
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Retained features of embryonic metabolism in the adult MRL mouse
PublikacjaThe MRL mouse is an inbred laboratory strain that was derived by selective breeding in 1960 from the rapidly growing LG/J (Large) strain. MRL mice grow to nearly twice the size of other commonly used mouse strains, display uncommonly robust healing and regeneration properties, and express later onset autoimmune traits similar to Systemic Lupus Erythematosis. The regeneration trait (heal) in the MRL mouse maps to 14-20 quantitative...
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A new finite element with variable Young's modulus
PublikacjaThe Finite Element Method (FEM) is a numerical technique that is well-established in the field of engineering. However, in biological sciences, it is justtaking its first steps. Bone tissue is an example of biological material which isexposed to high loads in its natural environment. Practically every movementof the body results in changing stress levels in the bone. Nature copes with thisvery well but when human intervention is...
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A comparative performance assessment of a hydrodynamic journal bearing lubricated with oil and magnetorheological fluid
PublikacjaThis work presents the investigation results of a journal bearing lubricated with magnetorheological fluid that is activated by a local constant magnetic field to vary both the local flow resistance and pressure. The bearing performance is assessed via Finite Element Modelling (FEM) and results are corroborated by experiments. The FEM model uses the Bingham model to describe the fluid film. A dedicated test rig is used to assess...
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GPU-Accelerated 3D Mesh Deformation for Optimization Based on the Finite Element Method
PublikacjaThis paper discusses a strategy for speeding up the mesh deformation process in the design-byoptimization of high-frequency components involving electromagnetic field simulations using the 3D finite element method (FEM). The mesh deformation is assumed to be described by a linear elasticity model of a rigid body; therefore, each time the shape of the device is changed, an auxiliary elasticity finite-element problem must be solved....
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Porous structure of natural and modified clinoptilolites
PublikacjaOpisano wyniki badań struktury porowatej naturalnych zeolitów. W badaniach wykorzystano technikę SEM oraz wyznaczono izotermy procesu adsorpcji-desorpcji azotu w temperaturze 77 st. K.
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Virulence gene profiles in Staphylococcus aureus isolated from cows with subclinical mastitis in eastern Poland
PublikacjaStaphylococcus aureus is arguably the most important pathogen involved in bovine mastitis. The aim of this study was to determine the virulence gene profiles of 124 Staph. aureus isolates from subclinical mastitis in cows in eastern Poland. The presence of 30 virulence genes encoding adhesins, proteases and superantigenic toxins was investigated by PCR. The 17 different combinations of adhesin genes were identified. Occurrence...
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OPRACOWANIE TECHNOLOGII OTRZYMYWANIA MEMBRAN CHITOZANOWYCH DO ZABIEGU STEROWANEJ REGENERACJI KOŚCI
PublikacjaPoniżej przedstawione badanie miało na celu wytworzenie asymetrycznych membran chitozanowych do zabiegu sterowanej regeneracji kości w stomatologii. W celu zbadania uzyskanej struktury wykonano mikrofotografie SEM.
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Numerical analysis and in situ tests of the Grot Rowecki Bridge in Warsaw
PublikacjaThe paper presents the FEM analysis of the reconstructed the Grot-Rowecki Bridge over Vistula river in Warsaw. The bridge has seven spans and consists of two independent structures with the longest spans of 120 m. After reconstruction the bridge is over 10 m wider. The numerical, nonlinear analysis has been con-ducted on a global and local FEM models. These models are defined so as they strictly comply with global structural bridge...
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Validation of polyurethane-wood composites properties
Dane BadawczeThis study focuses on the development of the PU-WC manufacturing method, the determination of properties of this type of composite, and the indication of its potential application. The mechanical properties of PU-WC were characterized by flexural tests. To determine the thermal properties, dynamic mechanical analysis (DMA) and thermogravimetric analysis...
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Rozumienie cechą inteligentnego przedsiębiotstwa
PublikacjaW artykule podniesiono istotę pojęcia ‘rozumienie’ w aspekcie inteligentnego przedsiębiorstwa. Przeprowadzone badania teoretyczne i empiryczne pozwoliły na wyłonienie rozumienia wewnętrznego i zewnętrznego. Rozumienie wewnętrzne w inteligentnym przedsiębiorstwie dotyczy sfer: pracowników oraz całego przedsię-biorstwa. Natomiast rozumienie zewnętrzne skierowane jest na otoczenie i potrze-bę dostosowania przedsiębiorstwa.
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Thermal decomposition of [Cd{SSi(OBut)3}(S2CNC4H8)]2 to CdS “micro-noodles”
PublikacjaThis work presents studies on thermal degradation of novel heteroleptic complex possessing mixed S-donor ligands, [Cd{SSi(OBut)3}(S2CNC4H8)]2 using TGA, DSC, TGA-IR, SEM and XRD methods.
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A higher order transversely deformable shell-type spectral finite element for dynamic analysis of isotropic structures
PublikacjaThis paper deals with certain aspects related to the dynamic behaviour of isotropic shell-like structures analysed by the use of a higher order transversely deformable shell-type spectral finite element newly formulated and the approach known as the Time-domain Spectral Finite Element Method (TD-SFEM). Although recently this spectral approach is reported in the literature as a very powerful numerical tool used to solve various...
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TB11 test for short w-beam road barrier
PublikacjaFEM (Finite Element Method) is well-suited and widely used tool for simulating a range of phenomena: from these with simple and static behaviour, up to those complicated, highly nonlinear and involving many contacts. In present paper we use one of the advantages of FEM: parametric study could be easily performed and is more economical than series of in-situ tests. If recommended practices is carefully followed, results obtained...
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Wybrane elementy nieliniowej dynamiki struktur kratowych
PublikacjaW pracy jest dyskutowany problem nieliniowej dynamiki struktur kratowych. Zastosowano stacjonarny opis Lagrange'a (ang. Total Lagrange), pokazano silne i słabe sformułowanie dla pręta kratowego, jego aplikację do MES. W zakresie całkowania równań ruchu przedstawiono metodę Newmarka i metodę-a dla problemów liniowych i nieliniowych. Załączony przykład numeryczny ilustruje cechy przedstawionych metod.
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Experimental and numerical evaluation of mechanical behaviour of composite structural insulated panels
PublikacjaComposite structural insulated panels (CSIPs) are novel prefabricated elements for structural applications. Panels under consideration are made from glass-fibre reinforced magnesia cement boards as facesheets and expanded polystyrene foam (EPS) as a core. Quasi-static full-scale and model bending tests under monotonic loading were performed to recognize mechanical properties of CSIPs in flexure. In addition, tensile, compressive,...
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Właściwości mechaniczne i morfologia kompozytów biopoliuretanowych wzmocnionych modyfikowanymi włóknami sizalowymi
PublikacjaOmówiono wyniki badań właściwości mechanicznych i morfologii kompozytów biopoliuretanowych (bio-PUR) zawierających 5-15% mas. krótkich włókien sizalu. Materiały te wytworzono z systemu poliuretanowego, w którym zdyspergowano włókno poddane wcześniej merceryzacji lub silanizacji. Charakterystykę wytrzymałościową w warunkach statycznych uzyskano z krzywych naprężenie-odkształcenie, a morfologię kompozytów oceniono na podstawie zdjęć...
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The study of structure and surface morphology of lithium titanate sol-gel derived thin films
PublikacjaIn this paper the structure and the surface morphology of lithium titanate (LTO) thin films are presented. Nanocrystalline thin films were prepared by sol–gel method. To examine the influence of the annealing time on as-prepared films crystallization, the coatings were heated at different temperatures in the range of 500 °C–600 °C for 10, 20, 40 and 80 h. The structure of the obtained material was investigated using the X-ray diffraction...
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Local and global response of sandwich beams made of GFRP facings and PET foam core in three point bending test
PublikacjaIn the paper behaviour of laminated sandwich beams (FRP face sheet – PET foam core – FRP face sheet) subjected to three point bending is studied. The paper aim is to find practical descriptions enabling effective and accurate estimation of the elastic response, damage and failure of the beams, basing on experiments and static calculations. Therefore a number of tests are described, that were done on laminated coupons and foam specimens...
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Antibacterial Activity and Cytocompatibility of Bone Cement Enriched with Antibiotic, Nanosilver, and Nanocopper for Bone Regeneration
PublikacjaBacterial infections due to bone replacement surgeries require modifications of bone cement with antibacterial components. This study aimed to investigate whether the incorporation of gentamicin or nanometals into bone cement may reduce and to what extent bacterial growth without the loss of overall cytocompatibility and adverse effects in vitro. The bone cement Cemex was used as the base material, modified either with gentamicin...
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A coupled constitutive model for fracture in plain concrete based on continuum theory with non-local softening and eXtended Finite Element Method
PublikacjaThe paper presents a constitutive model for concrete which combines a continuous and discontinuous fracture description. In a continuum regime, two different constitutive laws were used. First, a plasticity model with a Rankine failure criterion and an associated fl ow rule was used. Second, a constitutive law based on isotropic damage mechanics was formulated. In order to capture the width of a localized zone and to obtain mesh-independent...
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Elżbieta Marczak dr inż. arch.
OsobyElżbieta Marczak (dr inż. arch.) - adiunkt na Wydziale Architektury Politechniki Gdańskiej, zatrudniona Katedrze Architektury Miejskiej i Przestrzeni Nadwodnych (dawniej Katedra Architektury Morskiej i Przemysłowej, od roku 1997). Studia na Wydziale Architektury PG ukończyła w roku 1995. Stopień naukowy doktora uzyskała w 2006 r. przedstawiając pracę p.t. Architektura statków na tle rozwoju transportu morskiego. Jej badania naukowe...
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Affective reactions to playing digital games
PublikacjaThe paper presents a study of emotional states during a gameplay. An experiment of two-player Tetris game is reported, followed by the analysis of the results - self-reported emotional states as well as physiological signals measurements interpretation. The study reveals the diversity of emotional reactions and concludes, that a representative player's emotional model is hard to define. Instead, an adaptive approach to emotion...
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XPS investigations of tge tin/tin oxides - CNT composites
Dane BadawczeThe composite of tin/tin oxide nanoparticles with graphene oxide and CMC based on laser ablation technique as an electrode material for energy storage devices were manufactured. The material exhibited a three-dimensional conducting graphene oxide network decorated with tin or tin oxide nanoparticles. The presence of tin/tin oxide in composites was...
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Chemical composition of V2O5 nanorods
Dane BadawczeThe DataSet contains the chemical compositions of the V2O5 nanorods on a silicon substrate. The thin films were obtained by the sol-gel method. The information about sol synthesis is described in the Journal of Nanomaterials. The As-prepared thin films were annealed at 600C under a synthetic air atmosphere.
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Model of emotions for game players
PublikacjaAffect-aware video games can respond to a game player's emotions. Such games seem to be more attractive for users. Therefore for that kind of games it is necessary to create a model of the player's emotions to know to which emotions the application should react. The paper describes different models of emotions. The questionnaire and experiment for video game players is presented. Some results of the tests are shown. Then the model...
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A Note on Knowledge Management Education: Towards Implementing Active Learning Methods
PublikacjaKnowledge Management as an area of education is still a big challenge for teachers and practitioners. Nevertheless, there are several useful teaching methods in active education, especially oriented towards courses where innovation and delivering dynamic knowledge are critical. The goal of the paper is to present and discuss criteria relevant in the selection of active educational methods supporting knowledge management courses....
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Transcriptional profile of in vitro expanded human epidermal progenitor cells for the treatment of non-healing wounds
PublikacjaBackground Epidermal progenitor cells (EPCs) have been under extensive investigation due to their increasing potential of application in medicine and biotechnology. Cultured human EPCs are used in the treatment of chronic wounds and have recently became a target for gene therapy and toxicological studies. One of the challenges in EPCs culture is to provide a high number of undifferentiated, progenitor cells displaying high viability...