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Adaptation of the arbitrary Lagrange–Euler approach to fluid–solid interaction on an example of high velocity flow over thin platelet
PublikacjaThe aim of this study is to analyse the behaviour of a thin plate with air flow velocities of 0.3–0.9 Ma. Data from the experiment and numerical tools were used for the analysis. For fluid–solid interaction calculations, the arbitrary Lagrange–Euler approach was used. The results of the measurements are twofold. The first one is the measurement of the flow before and after vibrating plate, i.e. pure flow plate, and the second consists...
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Experimental dynamic study on a timber-frame house using shaking table
PublikacjaThe aim of this paper is to show the results of the shaking table experimental study concerning the behaviour of the model of the timber-frame house under earthquake excitation and impact loading. In order to determine the basic dynamic properties of the undamaged structure, the free vibration and the sweep-sine tests were first conducted. Then, the model was excited using the time history record of the El Centro earthquake of...
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Numerical analysis of a temporary steel grandstand
PublikacjaThe purpose of this paper is to present the results of the numerical analysis focused on the response of the temporary steel scaffolding grandstand subjected to human-induced vibrations due to jumping. Shell as well as beam elements have been used in the numerical model. Its first stage has involved conducting modal analysis in order to determine the modes of free vibrations and the corresponding natural frequencies for the empty...
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Preliminary results from HEDGEHOG REXUS project – A sounding rocket experiment on accelerations, vibrations and heat flow
PublikacjaDuring flight, a sounding rocket is subject to a unique environment - severe vibrations and substantial heat flux. In order to design payloads, precise measurement of these conditions is required. This paper presents preliminary results from HEDGEHOG REXUS Project, whose scientific goal was to characterise the thermal and dynamic environment of REXUS sounding rockets. For this purpose, two new sensors have been designed - mechanical...
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Monitorowanie i mapowanie zanieczyszczenia powietrza atmosferycznego przez związki z grupy BTEX (benzen, toluen, etylobenzen, ksylen) z wykorzystaniem techniki dozymetrii pasywnej do pobierania próbek analitów = Monitoring and mapping of atmospheric pollutans with the use of passive technique of sampling of BTEX (benzene, ethylbenzene, toluene, xylenes) analytes
PublikacjaWskutek działalności człowieka do atmosfery dostaje się coraz większa liczba substancji szkodliwych, uznanych za potencjalnie niebezpieczne dla organizmów żywych, głównie z uwagi na ich toksyczność. Do takich substancji zalicza się między innymi związki z grupy BTEX. Chcąc ocenić stopień narażenia populacji na obecność w powietrzu atmosferycznym analitów z grupy BTEX, niezbędne jest monitorowanie poziomu stężeń tych zanieczyszczeń...
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Dynamika bezzałogowego aparatu latającego w układzie czterowirnikowego pionowzlotu
PublikacjaDziałanie maszyn, w tym również pojazdów latających, jest nieodłącznie związane z przekazywaniem oddziaływań siłowych: statycznych i dynamicznych. Dynamika jest działem mechaniki zajmującym się makroskopowym ruchem ciał przy uwzględnieniu przyczyn wywołujących ten ruch. Pierwszym etapem analizy dynamiki konstrukcji są zwykle obliczenia wartości i postaci drgań własnych modelu konstrukcji. Drgania własne zwykle ulegają szybkiemu...
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Total electrical conductivity 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 dataset includes electrical conductivity measurements results measured by van der pauw technique up to 900oC.
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Application of different building representation techniques in HEC-RAS 2-D for urban flood modeling using the Toce River experimental case
PublikacjaThis paper presents the impact of the choice of building representation techniques and hydrodynamic models on urban flood simulations using HEC-RAS 2-D for the Toce River physical model. To this end, eight numerical models based on previous laboratory experiments were prepared to simulate unsteady urban flooding on each side of building units. Two simplified building layouts (aligned and staggered) were examined, where models were...
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Topographic AFM imaging of the leaf surface with magnification of details of its morphological structure
Dane BadawczeTopographic imaging of the leaf surface with magnification of details of its morphological structure. Measurements in semi-contact mode. NTEGRA Prima (NT-MDT) device. NSG 01 probe.
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Mode shapes of a beam and plate with defects, obtained by experimental modal analysis
Dane BadawczeThe DataSet contains the experimental results of the first mode shape for a beam and a plate.
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Experimental and numerical study on damage detection in an L-joint using guided wave propagation
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Stability of Discrete Fractional Order State-space Systems
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Experimental and numerical study on damage detection in an L-joint using guided wave propagation
PublikacjaW pracy zaprezentowano metodę wykrywania i lokalizacji uszkodzeń w konstrukcji ramowej za pomocą podłużnych i poprzecznych fal sprężystych. Przeprowadzono badania numerczyne i eksperymentalne na modelu bez uszkodzenia oraz na modelu z wsprowadzonym nacięciem. Do modelowania zastosowano metodę elementów spektralnych. W pracy przedstawiono sformułowanie nowego element spektralnego dla ram płaskich bazującego na teorii pręta Mindlina...
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Assessment of rod behavior theories used in spectral finite element modeling
PublikacjaW pracy przedstawiono teorie prętów i przedstawiono ich przydatnośc w analizie propagacji fal sprężystych z wykorzystaniem metody spektralnych elementów skończonych.
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The dynamic analysis of a cracked Timoshenko beam by the spectral element method
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Longitudinal wave propagation. Part I—Comparison of rod theories
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Wave propagation in a sensor/actuator diffusion bond model
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Longitudinal wave propagation. Part II—Analysis of crack influence
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Wave propagation modelling in 1D structures using spectral finite elements
PublikacjaW artykule omówiono modele propagacji fal wzdłużnych i poprzecznych w prętach oparte na dwóch sformułowaniach (w dziedzinie częstości i w dziedzinie czasu) metody elemntów spektralnych. Porównano otrzymane wyniki z wynikami eksperymentu.
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Modelling of wave propagation in composite plates using the time domain spectral element method
PublikacjaW pracy przedstawiono wyniki obliczeń propagacji fali sprężystej w płycie kompozytowej modelowanej z wykorzystaniem czasowego sformułowania metody elementów spektralnych
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Performance Characteristics of a Micro-Turbine
PublikacjaIn the paper a design of a multi-stage micro-turbine with partial admission of all the stages is described in detail and the results of particular experimental investigations and numerical calculations are shown, followed by conclusions. The co-generative micro-power plant with the HFE7100 as a working medium was designed and built for experimental investigations. The values of the main cycle parameters were as follows:heat output:...
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Partial Admission Stages of High Efficiency for a Microturbine
PublikacjaThe paper presents the results of a design analysis of a microturbine for a cogeneration micro-power plant working in accordance with organic Rankine cycle. The heat power of the plant is assumed equal to 20kW and the corresponding available electric output is estimated to be about 3 kW. After the design analysis, the axial turbine with partial admission in all stages was built and tested experimentally. Special attentionwas paid...
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Explanation of Reduction of Pressure Forces in Turbine Chamber Seals
PublikacjaThe paper describes a chamber seal reducing the aerodynamic forces created in shroud seals. Asymmetrical pressure distribution (due to rotor-stator eccentricity) in the blade tip clearance leads to the creation of pressure forces acting on the blade shroud. By increasing the volume above the shroud, the pressure distribution becomes more uniform on the whole shroud circumference and the effect of rotor eccentricity is reduced....
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The dynamic analysisi of cracked Thimoshenko beam by the spectral element method.
PublikacjaW pracy przedstawiono model belli Timoshenko z pęknięciem poprzecznym oparty o metodę elementów spektralnych. Przedstawiono wyniki propagacji fali sprężystej i jej interakcję z pęknięciem.
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Longitudinal wave propagation. Part II, Analysis of crack influence
PublikacjaW pracy analizowano wpływ pęknięć zmęczeniowych na propagacje fali wzdłużnej w prętach. Opracowano nowe typy element ów spektralnych oparte na teorii elementarnej, Love'a, Mindlina i trójpostaciowej.
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Longitudinal wave propagation. Part I - Comparison of rod theories
PublikacjaW pracy przedstawiono modele spektralnych elementów skończonych do analizy propagacji fali wzdłuznej w pretach. Opracowano modele wykorzystujace teorię elementarną, teorie Love'a, teorie Mindlina oraz teorię trójpostaciową.
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The Method of Reduction of Aerodynamic Forces Generated in Turbine Blade Seals
PublikacjaOpisano metodę zmniejszania sił wymuszających drgania aerodynamiczne poprzez zastosowanie nowego uszczelnienia nadbandażowego typu komorowego. Efektywność stosowania uszczelnienia komorowego potwierdzono obliczeniami numerycznymi i badaniami eksperymentalnymi.
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Assessment of flexural beam behaviour theories used for dynamics and wave propagation problems
PublikacjaW pracy przedstawiono i porównano teorie belek zginanych począwszych od teorii elementarnych, aż do teorii wyższych rzędów. Przedstawiono krzywe dyspersi dla poszczególnych teorii i na ich podstawione oszacowano zakres stosowalności danej teorii.
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Fast bubble dynamics and sizing
PublikacjaSingle bubble sizing is usually performed by measuring the resonant bubble response using the Dual Frequency Ultrasound Method. However, in practice, the use of millisecond-duration chirp-like waves yields nonlinear distortions of the bubble oscillations. In comparison with the resonant curve obtained under harmonic excitation, it was observed that the bubble dynamic response shifted by up to 20 percent of the resonant frequency...
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Pressure Pulsations in Turbine Blade Seal
PublikacjaThe paper presents the results of experimental investigations into pressure forces generated in a turbine labyrinth seal. The experiments were performed on a single-stage air model turbine of the impulse type. The performed experimental research proved that in a shroud clearance the pressure pulsates and the effects of the nozzle trailing edge thickness as well as the influence of the rotor blades are observed. The exemplary results...
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Considerations about the applicability of the Reynolds equation for analyzing high-speed near field levitation phenomena
Publikacjaequation for analyzing near field levitation (NFL) phenomena. Two separate approaches were developed, experimentally verified, and applied to meet the research objective. One was based on the Reynolds equation and the other was based on general conservation equations for fluid flow solved using computational fluid dynamic (CFD). Comparing the calculation results revealed that, for certain operating conditions, differences in the...
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Beata Krawczyk dr hab.
Osobydr hab. Beata Krawczyk, prof. uczelni Stopnie naukowe, wykształcenie, kwalifikacje Beata Krawczyk uzyskała tytuł magistra biologii na Wydziale Biologii (wówczas: Wydział Biologii i Nauk o Ziemi), Uniwersytetu Gdańskiego w 1986 roku, a doktorat z biologii molekularnej na Wydziale Biologii (wówczas: Wydział Biologii, Geografii i Oceanologii) Uniwersytetu Gdańskiego w 1996 roku. Stopień doktora habilitowanego w zakresie nauk biologicznych...
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Minimization of vibrations during milling of flexible structures using mechatronic design techniques
PublikacjaThe paper presents an innovative effective method of minimizing vibrations during milling of flexible structures, using a new vibration suppression method based on a workpiece holder with adjustable support stiffness. The proposed method is rooted in mechatronic design techniques, which can become a standard procedure for optimizing the milling process.
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Novel digitally controlled drive for the vibratory conveyors
PublikacjaThe presented vibratory conveyors is used in the industry for continuous transportation of loose substances over short distances (2-10 m). The conveyor is applied for transportation in aseptic conditions. To obtain high efficiency for granulatedmass with different size of grain and different physical properties it is necessary to set the appropriate vibration amplitudeindependently of vibration frequency. This is not possible with...
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Modal analysis of railway current collectors using Autodesk Inventor
PublikacjaThe paper presents the results of modal analysis of railway current collector type 160EC. In the first place, the analysis was carried out analytically for a simplified two lumped mass pantograph model. Then numerical analysis was conducted in the Autodesk Inventor (AI) on the prepared multibody model using the AI modal analysis algorithm, which is based on the finite element method (FEM). Model elements which are most relevant...
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Point cloud based surface analysis of prestressed concrete element in exceeded state of serviceability
PublikacjaBy definition, serviceability state is characterized by the fact that despite meeting the requirements associated with carrying capacity, the object is not suitable for use. Serviceability limit state refers to factors, such as durability, overall stability, fire resistance, cracking, excessive vibration. Perfect examples of exceeded serviceability state are the improper vibration of a skyscraper, which inhabitants may suffer from...
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Potential energy curves of LiCs dimer
Dane BadawczeThis data presents potential energy curves of LiCs dimer in Hund's case (a). Calculated using Born-Oppenheimer approximation with scalar relativistic effects are included via large effective core potentials. Custom basis sets, core polarization potentials and MRCI method are used to accurately describe electron correlation. Dataset consists of 22 potential...
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Potential energy curves of NaRb dimer
Dane BadawczeThis data presents potential energy curves of NaRb dimer in Hund's case (a). Calculated using Born-Oppenheimer approximation with scalar relativistic effects are included via large effective core potentials. Core polarization potentials and MRCI method is used to describe electron correlation. Dataset consists of 18 potential energy curves of ground...
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XRD data of (Cr,Fe,Mn,Co,Ni)3O4 High-entropy spinel oxide thin films deposited on amorphous SiO2 substrate by spray pyrolysis techniqe, annealed in a range from 400 to 900oC
Dane BadawczeDataset include collected XRD data of (Cr,Fe,Mn,Co,Ni)3O4 high-entropy spinel oxide thin films deposited by spray pyrolysis technique on amorphous SiO2 substrates and annealed from 400 to 900oC. Samples were prepared in the form of a ~ 500 nm thin film utilising a facile spray pyrolysis technique. The structural and electrical properties of the layers...
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A Meta-Analysis of Pulse Arrival Time Based Blood Pressure Estimation
PublikacjaThe paper presents a preliminary meta-analysis of the sample correlation between pulse arrival time (PAT) and blood pressure (BP). The aim of the study was to verify sample correlation coefficient between PAT and BP using an affine model BP = a · P AT + b for systolic and diastolic blood pressure. The databases included in the search were the IEEE Xplore Digital Library, Springer Link and Google Scholar. Only papers from 2005 to...
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Carbon Dioxide and Water Vapour Fluxes of a Alkaline Fen and Their Dependence on Reflectance
PublikacjaThis study shows results of parallel measurements of greenhouse gases fluxes (carbon dioxide and water vapour) and canopy reflectance of alkaline fen. Fluxes were measured using eddy-covariance technique on micrometeorological station located in the Upper Biebrza Basin (NE Poland) in Rogożynek Village. Study site is located in the Biebrza National Park which was established to protect one of the biggest coherent lowland wetland...
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Aggregation of imidazoacridinones - spectroscopic and microcalorimetric approach
PublikacjaImidazoacridinones (IA) belong to a group of polycyclic heteroaromatic antitumor compounds. IA create the aggregated form in water solution. Self-association of substances is a very important phenomenon in many fields of applied chemistry. It is also fundamental model reaction of many kinds of molecular interactions such as the micelle formation of amphiphilic substances and the binding of small organic molecules to macromolecules....
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Experimental determination of basic mechanical properties of elastomeric polymer
PublikacjaThere are a lot of different methods of repairing and reinforcing damaged structures, but when it comes to historical buildings and other cultural heritage objects, it is as much about mechanical safety as the aesthetical aspects. Recently, a new and innovative method of repairing damaged structures by filling the cracks with a specially prepared polymer mass has been proposed. This new and innovative technique, known as the Flexible...
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VSC converters control for offshore wind farms HVDC grid connection
PublikacjaThe paper proposes a voltage sourced converter (VSC) new control method. A well-known in the electric power systems correlation between voltage angle and active power and correlation between voltage and reactive power is used instead of feedforward control. This allows for a fast and almost independent control of active and reactive power flow.
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A Fortran-95 algorithm to solve the three-dimensional Higgs boson equation in the de Sitter space-time
Dane BadawczeA numerically efficient finite-difference technique for the solution of a fractional extension of the Higgs boson equation in the de Sitter space-time is designed. The model under investigation is a multidimensional equation with Riesz fractional derivatives of orders in (0,1)U(1,2], which considers a generalized potential and a time-dependent diffusion...
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The morphology of vanadate glass-ceramics containing BaTiO3 measured with the use of AFM
Dane BadawczeThe structure of vanadate glass-ceramics doped with BaTiO3 was measured by AFM technique. Samples of the composition of x[BaO,TiO2]–(80 − x)V2O5–20Bi2O3 where x = 5, 10 and 15 in mol% were prepared by a conventional melt quenching technique. The melting was performed in alumina crucibles at the temperature of 1273 K–1373 K. The melts were poured on...
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The ab initio and experimental study of the spectroscopic and magnetic properties of Ho(III)-EDTA
Dane BadawczeIn this dataset, the ab initio calculations of the electronic structure and the magnetic properties are discussed in the context of the experimental data for the Ho–EDTA complex. In the calculations different models of the cluster have been applied to examine the influence of various parts of the environment of the Ho(III)-EDTA complex on its properties....
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Full CI ground state potential energy curves and one-electron relativistic corrections for hydrogen molecule in various basis sets
Dane BadawczeThis dataset consists of Full CI ground state Born-Oppenheimer potential energy curves and one-electron relativistic corrections for hydrogen dimer. Nonrelativistic energies, as well as one electron relativistic corrections (treated perturbatively with help of the Cowan-Griffin Hamiltonian) are presented for internuclear distances between 0.8 and 10...
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Antiviral activity of bee bread derived from polish apiaries.
Dane BadawczeBee bread is a product of fermentation of bee-collected pollen and revealed a high nutritional value. Other bee products, such as honey and propolis, are known for their antiviral activity, but bee bread is still under investigation, thus its antiviral potential is still unspecified. For investigation antiviral activity of bee bread samples, cytotoxicity...
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Ljung-Box test values of selected companies of the Warsaw Stock Exchange
Dane BadawczeThe following dataset includes the Warsaw Stock Exchange market analysis using the Ljung-Box test. Partial autocorrelations up to the 5th order were analyzed, because it will allow to observe the relationship within one week of stock exchange quotations. In the case of the WIG index, the 1st and 2nd order correlation turned out to be statistically significant....