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Remote learning among students with and without reading difficulties during the initial stages of the COVID-19 pandemic
PublicationThis article presents the results of a survey on yet under-researched aspects of remote learning and learning difficulties in higher education during the initial stage (March – June 2020) of the COVID-19 pandemic. A total of 2182 students from University of Warsaw in Poland completed a two-part questionnaire regarding academic achievements in the academic year 2019/2020, living conditions and stress related to learning and pandemic,...
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A strategy of minimal torque modifications in a question of actuation strategy for an over-actuated system of a planar walking robot
PublicationPraca opisuje zagadnienia modelowania i napędzania robotów kroczących. Na pewnych etapach ruchu, konstrukcje takie są układami napędzanymi nadmiarowo (liczba napędów/silników jest większa niż liczba stopni swobody układu). Dzieje się tak z uwagi na więzy jednostronne występujące w układzie. Dla układów płaskich, po pojawieniu się kontaktu koła i odnóża, układ o sześciu stopniach swobody przechodzi w układ o trzech stopniach swobody....
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Evaluation of Surface Topography after Face Turning of CoCr Alloys Fabricated by Casting and Selective Laser Melting
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DSC Melting Profile of Cold-Pressed Hemp Seed Oil as an Authenticity Fingerprint Influenced by Scanning Rate
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Four-state measurement method for direct-reading noise figure measurement of low-gain two-ports.
PublicationOmówiono problemy techniczne pomiaru współczynnika szumu dwuwrotników o małym wzmocnieniu mocy dysponowanej realizowanych przy stosowaniu znanych metod pomiaru współczynnika szumu. Przedstawiono nową czterostanową metodę pomiaru umożliwiającą uniezależnienie wskazań automatycznego miernika współczynnika szumu zarówno od wartośći wzmocnienia dwuwrotnika badanego jak i współczynnika szumu odbiornika pomiarowego. Wyprowadzone zależności...
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Process [Intellectual Output 2] Guidelines for a design process leading to a high-quality Baukultur in the digital age
PublicationThe main aim of the intellectual output “Process” is to identify, explore and evaluate new design processes for shaping the built environment, which are informed, collaborative, and adaptable, allow customization and are generally enabled by the application of digital tools. Further, it aims at creating methodological guidelines for future-oriented design processes leading to a high-quality Baukultur in the digital age. The guidelines...
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Winding function approach based design of novel five-phase brushless doubly fed induction generator
PublicationThe paper presents the concept of the new design of the five-phase brushless doubly fed induction generator. The generator is dedicated to the modern wind turbine. The innovative design approach uses a five-phase power supply from the stator control winding side of the generator with a stator three-phase classic power winding. The research results presented indicate that the electromagnetic coupling between the control and power...
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Bending and buckling formulation of graphene sheets based on nonlocal simple first-order shear deformation theory
PublicationThis paper presents a formulation based on simple first-order shear deformation theory (S-FSDT) for large deflection and buckling of orthotropic single-layered graphene sheets (SLGSs). The S-FSDT has many advantages compared to the classical plate theory (CPT) and conventional FSDT such as needless of shear correction factor, containing less number of unknowns than the existing FSDT and strong similarities with the CPT. Governing...
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Textile reinforced concrete members subjected to tension, bending, and in-plane loads: Experimental study and numerical analyses
PublicationTextile reinforced concrete has raised increasing research interest during the last years, mainly due to its potential to be used for freeform shell structures involving complex load situations. Yet, most experimental work has focused on test setups with primarily uniaxial loading. In the current work, such setups are complemented with a novel test setup of deep beams, including in-plane bending and shear. Further, nonlinear finite...
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Gene and Protein Accumulation Changes Evoked in Porcine Aorta in Response to Feeding with Two Various Fructan Sources
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Determinants of the surface quality, density and dimensional correctness in selective laser melting of the Ti-13Zr-13Nb alloy
PublicationSelective laser melting is widely used for custom-designed elements. Successful manufacturing depends on laser treatment parameters and material features. This research aimed to determine the effects of laser power, scan time and hatch distance on surface quality, relative density and dimensional precision for cuboids made of the Ti-13Zr-13Nb alloy. The influence of energy density, energy flux and pre-heating was seen to be decisive...
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Study of prototype multi-pole non-salient field winding for high speed brushless synchronous generator
PublicationIn this paper a non-salient field winding for a brushless synchronous generator working with high speed in an autonomous energy generation system (e.g. airplane power grid) has been presented. A conception of a six-pole cylindrical-rotor with distributed field winding has been proposed. Comparison study of salient and prototype non-salient field winding has been carried out. Chosen simulation and measurement results of the generator...
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Evolution of magnetic and transport properties in (Cr1−xMnx)2AlC MAX-phase synthesized by arc melting technique
PublicationHerein we initiate a comeback to the arc melting technique to produce MAX-phase solid solutions. Bulk samples of (Cr1−xMnx)2AlC MAX-phase with X = 0, 0.025, 0.05 and 0.1 were synthesized and studied by means of X-ray diffractometry, scanning electron microscopy in combination with energy-dispersive X-ray spectroscopy. Samples were established to be homogeneous with an incorporation of Cr7C3, AlCr2 and Al2O3 secondary phases which...
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NON-LOCAL VOLUMETRIC APPROACH TO ANALYSIS DEFECT'S SHAPE INFLUENCE ON SPECIMENS DURABILITY SUBJECTED TO BENDING AND TORSION
PublicationThe influence of defect features on fatigue behaviour is a complex trivial issue. Although the important advances over the last decades, the dialectical relationship between the defect orientation and durability is not clearly understood. The paper aims at studying the influence of the orientation of elliptical defects on the durability of samples made of C45 steel. Three types of samples with elliptical defects were subjected...
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Correlation between Fractal Dimension and Areal Surface Parameters for Fracture Analysis after Bending-Torsion Fatigue
PublicationThis paper investigates the fracture surface topography of two steel and aluminum alloys subject to bending-torsion fatigue loadings, as well as their susceptibility to fatigue performance and failure mechanisms. Using fracture surface topography data analysis, elements with different geometries were elaborated. A correlation between the fractal dimension, other selected parameters of surface topography such as areal Sx, and...
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Rotational molding of polylactide (PLA) composites filled with copper slag as a waste filler from metallurgical industry
PublicationThe research work carried out so far indicates the ever wider possibilities and demand for shaping composite products in the rotational molding technology. This trend was the main reason to use waste-based filler from the metallurgical process as a filler for manufacturing polylactide (PLA)-based remolded composites. Copper slag (CS) was introduced in the single-step processing method to PLA matrix at 5, 10, 20, and 35 wt%. The...
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The impact of surface slope and calculation resolution on the fractal dimension for fractures of steels after bending-torsion fatigue
PublicationThe article presents the results of the fractal dimension measurements on the fatigue fracture surfaces of 10HNAP and S355J2 steels specimens after combined bending-torsion fatigue. For smooth and ring-notched specimens, three loading conditions were analyzed: (1) bending; (2) bending-torsion; and (3) torsion fatigue. Post-failure surface topography measurements were carried out on the entire fracture surfaces using an optical...
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A new anisotropic bending model for nonlinear shells: Comparison with existing models and isogeometric finite element implementation
PublicationA new nonlinear hyperelastic bending model for shells formulated directly in surface form is presented, and compared to four existing prominent bending models. Through an essential set of elementary nonlinear bending test cases, the membrane and bending stresses of each model are examined analytically. Only the proposed bending model passes all the test cases, while the other bending models either fail or only pass the test cases for...
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Synthesis, structural characterization, and thermal properties of Ca‐ and La‐doped soda‐lime glasses by laser melting
PublicationLaser melting techniques have been used in the preparation of unconventional glass compositions with high melting temperatures. Thus, we wanted to test the feasibility of using a CO2 laser in the preparation of nitrogen-rich oxynitride glasses and nitride silicate glasses. Melting from oxides and metallic raw materials, we wanted to study first glass formation and possible evaporation losses of the glass components. Two glass series...
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Post-comatose patients with minimal consciousness tend to preserve reading comprehension skills but neglect syntax and spelling
PublicationModern eye tracking technology provides a means for communication with patients suffering from disorders of consciousness (DoC) or remaining in locked-in-state. However, being able to use an eye tracker for controlling text-based contents by such patients requires preserved reading ability in the first place. To our knowledge, this aspect, although of great social importance, so far has seemed to be neglected. In the paper, we...
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Calculations of fracture process zones on meso-scale in notched concrete beams subjected to three-point bending.
PublicationW artykule przedstawiono wyniki numeryczne MES modelowanie belek betonowych z nacięciem na poziomie skali mezo. Beton został opisany na poziomie skali mezo jako stochastyczny materiał 3-składnikowy złożony z kruszywa, zaczynu cementowego oraz stref kontaktu. Obliczenia wykonano przy wykorzystaniu modelu degradacji sztywności z nielokalnym osłabieniem. Zbadano wpływ stochastycznego rozkładu kruszywa, średnicy, kształtu oraz zagęszczenia...
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Finite element analysis on failure of reinforced concrete corner in sewage tank under opening bending moment
PublicationW artykule omówiono mechanizm uszkodzenia żelbetowego zbiornika ściekowego w narożniku ściany, który uległ uszkodzeniu podczas próby wypełnienia na skutek nadmiernych przemieszczeń poziomych ścian pod wpływem otwierającego momentu zginającego. Aby wyjaśnić przyczyny awarii, przeprowadzono kompleksowe obliczenia metodą elementów skończonych (MES) żelbetowego zbiornika w warunkach odkształcenia płaskiego. Beton zamodelowano za pomocą...
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Investigations on fracture in reinforced concrete beams in 3-point bending using continuous micro-CT scanning
PublicationThis study explores a fracture process in rectangular reinforced concrete (RC) beams subjected to quasi-static three-point bending. RC beams were short and long with included longitudinal reinforcement in the form of a steel or basalt bar. The ratio of the shear span to the effective depth was 1.5 and 0.75. The focus was on the load–deflection diagram and crack formation. Three-dimensional (3D) analyses of the size and distribution...
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Parametric FE studies on a coupled energetic-statistical size effect in plain concrete beams under bending
PublicationW artykule omówiono wyniki połączonego deterministyczno-statystycznego efektu skali w betonowych belkach podczas zginania. Obliczenia wykonano stosując MES w zakresie sprężysto-plastyczności z nielokalnym osłabieniem. Obliczenia wykonano dla różnych długości korelacji i współczynnika zmienności.
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Zgrzewanie tarciowe z mieszaniem wewnętrznym zgrzeiny stopów aluminium AW7075-T651 i AW6082-T6 = Friction stir welding of aluminium alloys AW-7075-t651 and AW-6082-t6
PublicationW pracy przedstawione są wyniki badań nad złączami doczołowymi zgrzewanymi przy użyciu technologii Friction Stir Welding (FSW), wykonanymi z wysokowytrzymałego stopu Al-Zn (AW-7075-T651) oraz stopu Al-Mg2Si (AW-6082-T6) o wysokiej odporności na korozję. Stop AW-7075-T651 okazał się bardziej podatny na obniżenie własności mechanicznych w odniesieniu do materiału rodzimego. Złącza ze stopu AW-6082-T6 wykazały się lepszą plastycznością....
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Journal of Literacy Research (Formerly: Journal of Reading Behaviour)
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Nonlocal nonlinear bending of rectangular nanoscale plate including central hole via complex differential quadrature method
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Gender and Body-Fat Status as Predictors of Parental Feeding Styles and Children’s Nutritional Knowledge, Eating Habits and Behaviours
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The Effect of Freezing Sheep’s Milk on the Meltability, Texture, Melting and Fat Crystallization Profiles of Fresh Pasta Filata Cheese
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Impact of orthostatic hypotension and antihypertensive drug treatment on total and cardiovascular mortality in a very elderly community-dwelling population
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Effects of Three-Month Feeding High Fat Diets with Different Fatty Acid Composition on Myocardial Proteome in Mice
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Feeding milk replacer instead of whole milk affects blood plasma proteome and lipid profile in preruminant calves
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Inhomogeneity of low-noise wearing courses evaluated by tire/road noise measurements using the close-proximity method
PublicationPerforming numerous analyses of tire/road noise measurements on low-noise pavements during the last several years, the authors observed significant inhomogeneity of the wearing course in numerous cases, while similar problems were almost non-existent when dense pavements were measured. Three main causes of low-noise pavement inhomogeneity can be defined. The first one is imperfections in the technology used for asphalt mix production...
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Striving for spatial energy efficiency in dwelling complexes. Kształtowanie przestrzennej efektywności energetycznej w zespołach zabudowy mieszkaniowej.
PublicationThe main aim of this article was to discover the key characteristics in shaping most rewarded eco- district complexes built respectively in temperate climate zone in respect to spatial energy efficiency and resilience principles. It was done through careful case studies, comparative analysis and juxtaposition of critical parameters related to spatial energy efficiency and resilience in chosen representative dwelling complexes....
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Laboratory research on the influence of swelling clay on the quality of borehole cementing and evaluation of clay-cutting wellbore tool prototype
PublicationSwelling clay phenomenon is frequently observed during oil and gas drilling operations and has a significant impact on the quality of cementing procedure. Certain types of clayey minerals increase their volume in contact with water-based drilling fluids. After drilling is completed, borehole remains unsupported and filled with waterbased drilling fluids for several hours, before a casing string is inserted and secured with cement....
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Influence of Wood Moisture on Strength and Elastic Modulus for Pine and Fir Wood Subjected to 4-point Bending Tests
PublicationThe main purpose of this research paper was to determine the influence of the wood moisture on the strength and elastic modulus of pine and fir wood specimens subjected to the 4-point bending tests. Six bending tests for each wood species and for two different moisture level have been performed. Then, the advanced statistical analysis of the results has been carried out. On the basis of the obtained results, it has been noted that...
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ATTEMPT AT EVALUATING THE INFLUENCE OF BENDING STRESS ON SHAFT WEAR PROCESSES IN WATER LUBRICATED SLIDING BEARING WITH A RUBBER BUSHING
PublicationWater lubricated bearings find increasingly wide application in shipbuilding or hydro–power industry, the popularity stemming from their numerous advantages. Unfortunately, as it turns out, water lubricated bearings do not always meet expectations, as on occasion they become subject to intense, premature wear which requires costly repair. One of the still unexplained phenomena is the process of excessive bearing wear, in particular...
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Fracture Surface Behavior of 34CrNiMo6 High-Strength Steel Bars with Blind Holes under Bending-Torsion Fatigue
PublicationThe present study evaluates the fracture surface response of fatigued 34CrNiMo6 steel bars with transverse blind holes subjected to bending with torsion loading. The analysis of the geometric product specification was performed by means of height parameters Sx, functional volume parameters Vx, and fractal dimension Df. Surface topography measurements were carried out using an optical profilometer with focus variation technology....
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Quantitative assessment of the influence of tensile softening of concrete in beams under bending by numerical simulations with XFEM and cohesive cracks
PublicationResults of the numerical simulations of the size effect phenomenon for concrete in comparison with experimental data are presented. In-plane geometrically similar notched and unnotched beams under three-point bending are analyzed. EXtended Finite Element Method (XFEM) with a cohesive softening law is used. Comprehensive parametric study with the respect to the tensile strength and the initial fracture energy is performed. Sensitivity...
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Changes on the Surface of the SiO2/C Composite, Leading to the Formation of Conductive Carbon Structures with Complex Nature of DC Conductivity
PublicationSol–gel layers have been the subject of many studies in recent decades. However, very little information exists about layers in which carbon structures are developed in situ. Using the spin-coating method, we obtained thin iron-doped SiO2/C composite films. The results of Raman spectroscopy showed that our samples consisted of graphitic forms and polymers. The latter’s contribution decreases with rising temperature. FTIR and EDS...
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Fractographic-fractal dimension correlation with crack initiation and fatigue life for notched aluminium alloys under bending load
PublicationIn this study, fatigue fracture surfaces of aluminium alloy 2017-T4 notched specimens were investigated under cyclic bending to find an alternative failure loading index.. The surface topographies were measured on the entire fracture area with an optical profilometer for different loading conditions. Fatigue crack initiation life Ni and total fatigue life Nf were examined using standard surface topography parameters (such as, root...
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Concrete beams under bending - calculations of size effects within stochastic elasto-plasticity with non-local softening
PublicationW artykule przedstawiono wyniki numerycznej analizy efektów skali (efektu deterministycznego i stochastycznego) w belkach betonowych nacięciem poddanych zginaniu z uwzględnieniem lokalizacji odkształceń. Obliczenia wykonano przy zastosowaniu metody elementów skończonych i sprężysto-plastycznego modelu z nielokalnym osłabieniem. Pokazano wpływ wielkości belek betonowych na nośność.
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Technical Mechanics 2 (PG_00049753), I stop, En, [W,C], zima 22/23
e-Learning CoursesLectures and tutorials devoted to basic issues of Strength of Materials (stress and strain states, the Hook's law, geometrical properties of an area, bending, shearing, torsion, deflection lines of beams, buckling and yielding criteria).
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Multibeam Sonar Data Processing for Seafloor Classification
PublicationDespite many years of the development of methodology for sensing the seafloor by means of underwater acoustics, the currently used techniques are still not mature enough and not ready to be utilised in numerous different (i.e. with respect to a water region character, used equipment type etc.) tasks. Therefore the hydroacoustic methods, both utilising vertical observations (e.g. by singlebeam echosounders), as well as those relying...
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Monitoring of Caged Bluefin Tuna Reactions to Ship and Offshore Wind Farm Operational Noises
PublicationUnderwater noise has been identified as a relevant pollution affecting marine ecosystems in different ways. Despite the numerous studies performed over the last few decades regarding the adverse effect of underwater noise on marine life, a lack of knowledge and methodological procedures still exists, and results are often tentative or qualitative. A monitoring methodology for the behavioral response of bluefin tuna (Thunnus thynnus)...
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PCR Melting Profile method for genotyping analysis of vancomycin-resistant Enterococcus faecium isolates from Hematological Unit patients
PublicationW ostatnich latach znacząco wzrasta liczba szczepów Enterococcus opornych na wankomycynę. Stwarzają one problemy medyczne u pacjentów skolonizowanych czy zainfekowanych tymi drobnoustrojami. W przedstawionych badaniach, określiliśmy genetyczne podobieństwo pomiędzy izolatami E. faecium VRE, pozyskiwanymi w okresie od kwietnia 2003 do kwietnia 2005 od pojedynczych pacjentów oddziału Hematologicznego Specjalistycznego Publicznego...
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DNA methylation analysis with methylation‐sensitive high‐resolution melting (MS‐HRM) reveals gene panel for glioma characteristics
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Effect of multiaxial bending-torsion loading on fracture surface parameters in high-strength steels processed by conventional and additive manufacturing
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Effect of non-zero mean stress bending-torsion fatigue on fracture surface parameters of 34CrNiMo6 steel notched bars
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A fractographic study exploring the fracture surface topography of S355J2 steel after pseudo-random bending-torsion fatigue tests
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