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Search results for: ab initio calculations
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New Tetragonal ReGa5(M) (M = Sn, Pb, Bi) Single Crystals Grown from Delicate Electrons Changing
PublicationSingle crystals of the new Ga-rich phases ReGa~5(Sn), ReGa~5(Pb) and ReGa~5(Bi) were successfully obtained from the flux method. The new tetragonal phases crystallize in the space group P4/mnc (No. 128) with vertex-sharing capped Re2@Ga14 oblong chains. Vacancies were discovered on the Ga4 and Ga5 sites, which can be understood as the direct inclusion of elemental Sn, Pb and Bi into the structure. Heat capacity measurements were...
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Reactivity of bulky aminophosphanes towards small molecules: Activation of dihydrogen and carbon dioxide by aminophosphane/borane frustrated Lewis pairs
PublicationA series of mono- and bisaminophosphanes with formulas R2NPR’R’’ and (R2N)2PR’ (R = iPr, Cy; R’ = Ph, Cy; R’’ = iPr) were characterized by X-ray analysis, NMR spectroscopy and computational methods. The common structural futures of these species are short and polarized PAN bonds, a pyramidal geometry at the P atom and an almost planar geometry at the N atoms. According to DFT calculations, these...
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Influence of Gaps’ Geometry Change on Leakage Flow in Axial Piston Pumps
PublicationAxial piston pumps are the core elements of most medium and high-pressure hydraulic systems. High volumetric efficiency and high working pressures are the main advantages of this type of pumps. Therefore it is necessary to accurately calculate the leakage flow through the gaps to design efficient high-pressure pump. The main difficulty of such calculations is the fact, that the gaps change their geometry during pumping process....
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Carboxylation Enhances Fragmentation of Furan upon Resonant Electron Attachment
PublicationWe report a dissociative electron attachment study to 2-furoic acid (C5H4O3) isolated in a gas phase, which is a model molecule consisting of a carboxylic group and a furan ring. Dissociation of furan by low energy electrons is accessible only via electronic excited Feshbach resonances at energies of incident electrons above 5 eV. On the other hand, carboxylic acids are well- known to dissociate via attachment of electrons at subexcitation energies....
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Determination of the theoretical and actual working volume of a hydraulic motor
PublicationA new methodology of determination of the theoretical and actual working volume of a hydraulic motor based on the characteristics of the delivered flow rate into hydraulic motor vs. the rotational speed at a constant pressure drop in the working chambers is described in this paper. A new method of describing the delivered flow rate into a motor per one shaft revolution as a nonlinear function of the pressure drop in the motor working...
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Visualization of a lifeboat motion during lowering along ship’s side
PublicationThis paper presents description of a computer program for motion visualization of a lifeboat lowered along ship’s side. The program is a post-processor which reads results of numerical calculations of simulated objects’ motions. The data is used to create scene composed of 3D surfaces to visualize mutual spatial positions of a lifeboat, ship’s side and water waving surface. Since the numerical data contain description of a simulation...
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A spatio-temporal approach to intersectoral labour and wage mobility
PublicationThe article presents the spatio-temporal approach for intersectoral labor and wage mobility. Analyses of interindustry mobility were performed with the use of general entropy mobility indices (GEMM). Spatio- temporal approach was obtained thanks to the separate measurement of spatial autocorrelation and regression for each set of sectoral wage and employment structure and was conducted in each year of the research period separately....
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A Spatio-temporal Approach to Intersectoral Labour and Wage Mobility
PublicationThe article presents the spatio-temporal approach for intersectoral labor and wage mobility. Analyses of interindustry mobility were performed with the use of general entropy mobility indices (GEMM). Spatio-temporal approach was obtained thanks to the separate measurement of spatial autocorrelation and regression for each set of sectoral wage and employment structure and was conducted in each year of the research period separately....
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Modelling of Longitudinal Elastic Wave Propagation in a Steel Rod Using the Discrete Element Method
PublicationThe paper deals with the issue of modelling elastic wave propagation using the discrete element method (DEM). The case of a longitudinal wave in a rod with a circular cross-section was considered. A novel, complex algorithm consisting of the preparation of models and simulation of elastic waves was developed. A series of DEM models were prepared for simulations, differing in discretisation and material parameters. Additional calculations...
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The Impact of Sloshing Liquids on Ship Stability for Various Dimensions of Partly Filled Tanks
PublicationLiquid sloshing phenomenon taking place in partly filled ships' tanks directly affects the stability of a vessel. However, only static calculations are carried out onboard ships nowadays and static transfer of liquid weight is taken into account in the course of routine stability calculation. The paper is focused on a dynamic heeling moment due to liquid sloshing in tanks onboard ships. A number of numerical simulations of liquid...
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A Method of Assessment of the Liquid Sloshing Impact on Ship Transverse Stability
PublicationLiquid sloshing phenomenon taking place in partly filled ships? tanks directly affects the stability of a vessel. However, only static calculations are carried out onboard ships nowadays and static transfer of liquid weight is taken into account in the course of routine stability calculation. The paper is focused on a dynamic heeling moment due to liquid sloshing in tanks onboard ships. The set of numerical simulations of liquid...
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HEAVE MOTION OF A VERTICAL CYLINDER WITH HEAVE PLATES
PublicationThe shape of a vertical cylinder resembles the classic form of a spar platform. Spar platforms are floating platforms that are successfully used in waters of great depths and have several advantages that mean they are readily used in the oil industry. Many of these advantages are also relevant to their application for offshore wind turbines, which is currently being considered. In the hydrodynamic analysis of spar platforms, the...
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Spontaneous electron emission vs dissociation in internally hot silver dimer anions
PublicationReferring to a recent experiment, we theoretically study the process of a two-channel decay of the diatomic silver anion (Ag2-), namely the spontaneous electron ejection giving Ag2 + e- and the dissociation leading to Ag- + Ag. The ground state potential energy curves of the silver molecules of diatomic neutral and negative ion were calculated using proper pseudo-potentials and atomic basis sets. We also estimated the non-adiabatic...
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The assessment of metrological properties of segmental orifice based on simulations and experiments
PublicationSegmental orifices are often used to measure flows of heterogeneous mixtures, especially in flow meters in the power industry, for example. The orifice (with module m= 0.25) was installed in a stainless-steel pipe with internal diameter of 50 mm, placed in a hydraulic water system. The research was performed for Reynolds numbers ranging from 9,000 to 17,000. The flow characteristics of this orifice obtained based on simulation...
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Strong-coupling superconductivity of SrIr2 and SrRh2 : Phonon engineering of metallic Ir and Rh
PublicationExperimental and theoretical studies on superconductivity in SrIr2 and SrRh2 Laves phases are presented. The measured resistivity, heat capacity, and magnetic susceptibility confirm the superconductivity of these compounds with Tc = 6.07 and 5.41 K, respectively. Electronic structure calculations show that the Fermi surface is mostly contributed by 5d (4d) electrons of Ir (Rh), with Sr atoms playing the role of electron donors....
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Design Evolution of the Ultrasonic Piezoelectric Motor Using Three Rotating Mode Actuators
PublicationThe development process and experimental investigation of the multicell piezoelectric motor is presented in this paper. The proposed design consists of three individual cells integrated into the stator, double rotor, and a preload system. Those elements are combined into a symmetrical structure of the motor. The two new prototypes have been designed, simulated and tested. Finite element numerical analysis is carried out to obtain...
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A Direct Modulation for Matrix Converters based on the Onecycle Atomic operation developed in Verilog HDL.
PublicationThis paper presents a fast direct Pulse Width Modulation (PWM) algorithm for the Conventional Matrix Converters (CMC) developed in Verilog Hardware Description language (HDL). All PWM duty cycle calculations are performed in one cycle by an atomic operation designed as a digital module using FPGA basic blocks. The algorithm can be extended to any number of output phase. The improved version of the discontinuous Direct Analytic...
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Detection of debonding in adhesive joints using Lamb wave propagation
PublicationAdhesively bonded joints are widely used in many branches of industry. Mechanical degradation of this type of connections does not have significant symptoms that can be noticed during visual assessment, so non-destructive testing becomes a very important issue. The paper deals with experimental investigations of adhesively bonded steel plates with different defects. Five samples (an intact one and four with damages in the form...
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Large deformation modelling of CPT probing in soft soil—pore water pressure analysis
PublicationThis paper presents the results of finite element modelling with Updated Lagrangian formulation of the Cone Penetration Test in soft soil deposit located in Jazowa, Poland. The numerical calculations are carried out for homogenous, normally consolidated, organic soil layer. The Modified Cam Clay constitutive model for soft soil and Coulomb model for interface are used. The study compares the registered pore water pressure distributions...
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Design and Experiments of a Piezoelectric Motor Using Three Rotating Mode Actuators
PublicationThis paper represents a numerical and experimental investigation of the multicell piezoelectric motor. The proposed design consists of three individual cells that are integrated into the stator, double rotor, and a preload system combined into a symmetrical structure of the motor. Each of the cells is characterized by a traveling wave and rotating mode motor. A finite element numerical analysis is carried out to obtain optimal...
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A study on microcrack monitoring in concrete: discrete element method simulations of acoustic emission for non-destructive diagnostics
PublicationThe research is focused on the monitoring of fracture evolution in concrete beams under three-point bending using the acoustic emission technique and the discrete element method. The main objective of the study was to numerically and experimentally investigate the mechanism behind the generation of elastic waves during acoustic emission events and their interaction with micro- and macro-cracking in concrete beams under monotonic...
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Modyfikacja połączenia dźwigara ze słupem w konstrukcji stalowej Terminalu T2 Portu Lotniczego w Gdańsku
PublicationW2015 r. ukończono rozbudowę Terminalu T2 Portu Lotniczego im. Lecha Wałęsy wGdańsku. Politechnika Gdańska pełniła nadzór naukowy nad rozbudową obiektu. Wykonano wiele analiz, których celem była weryfikacja pracy konstrukcji w fazach montażu oraz w stanie docelowym. Wnioski z przeprowadzonych badań doprowadziły do modyfikacji oparcia dźwigarów dachowych na stalowych słupach nośnych, z uwagi na stwierdzone lokalne przekroczenia...
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Skutki zwarć łukowych w średnionapięciowych rozdzielnicach okrętowych z izolacją powietrzną
PublicationW artykule scharakteryzowano moc i napięcie łuku, jak również przedstawiono model termodynamiczny służący do obliczania ciśnienia i temperatury gazów w otoczeniu łuku zwarciowego. Przedstawiono przykładowy układ elektrowni okrętowej i zasilania najważniejszych odbiorników na statku do przewozu kontenerów, w tym 600 kontenerów chłodzonych. Na podstawie parametrów prądnic i silników, odbiorników zasilanych z rozdzielnicy głównej...
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Wydłużanie krzywej przejściowej w analitycznej metodzie projektowania
PublicationW pracy przedstawiono problematykę wydłużania krzywych przejściowych, wykorzystując do tego celu analityczną metodę projektowania. Podstawę analizy stanowiły obliczenia numeryczne przeprowadzone dla szerokiego zestawu parametrów charakteryzujących standardowy układu geometryczny. Po sformułowaniu odpowiednich zależności teoretycznych rozpatrzono kwestie znaczenia wielkości promienia łuku kołowego i kąta zwrotu trasy na uzyskane...
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Modelowanie losowych imperfekcji geometrycznych przestrzennych konstrukcji metalowych
PublicationImperfekcje geometryczne zbiorników, silosów i powłok siatkowych mogą znaczą-co wpłynąć na ich nośność, a więc powinny być one uwzględniane w obliczeniach komputerowych i w procesie projektowania. Wykazano, że przy podstawowych obcią-żeniach, działających na tego typu konstrukcje, tj. podciśnieniu oraz naporu wiatru i śniegu (w przypadku powłok siatkowych), wykazują wyraźne różnice w porównaniu z analogicznymi wynikami dla tych...
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Numeryczna analiza dynamiczna wieszaków w łukowym wiadukcie kolejowym. Analiza przypadku
PublicationW artykule przedstawiono analizę dynamiczną wiaduktu kolejowego w ciągu Centralnej Magistrali Kolejowej zlokalizowanego koło Huty Zawadzkiej. W analizie zwrócono szczególną uwagę na lokalną odpowiedź wieszaków na obciążenie przejeżdżającym pociągiem oraz wiatrem. Obliczenia przeprowadzono na podstawie wykonanego modelu MES. Zweryfikowano poprawność modelu poprzez porównanie uzyskanych wyników z wartościami pomierzonymi. Przeprowadzono...
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Measurements of the fundamental harmonic frequency of voltages on main bars in a ship power station
Open Research DataThe presented dataset is part of research focusing on the assessment of metrological properties of the instrument, Estimator/Analyzer (E/A v.2), developed and made at the Faculty of Electrical Engineering, Department of Marine Electrical Power Engineering of Gdynia Maritime University. The attached dataset contains processed data, expressing the fundamental...
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Measurements of the rms voltages on main bars in a ship power station with two generators operating in parallel
Open Research DataThe presented dataset is part of research focusing on the assessment of metrological properties of the instrument, Estimator/Analyzer (E/A v.2), developed and made at the Faculty of Electrical Engineering, Department of Marine Electrical Power Engineering of Gdynia Maritime University. The attached dataset contains processed data, expressing the rms...
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Polyacrylamide substrate viscosity impact on temozolomide activity in glioblastoma cells by flow cytometry and rheological measurements
Open Research DataDataset includes raw data on cell lines LN-229 and LN-18 treated with temozolomide measured by flow cytometry, rheometry and cell projections. It also includes calculations necessary for creation of figures and conclusions based on those figures in the publication titiled: "Substrate viscosity impairs temozolomide-mediated inhibition of glioblastoma...
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Electronic transition dipole moment functions of the first singlet Delta gerade and first triplet Delta ungerade states of the Lithium dimer
Open Research DataElectronic transition dipole moment functions (ETDMF) of the first singlet Delta gerade (1sDg) and first triplet Delta ungerade (1tDu) states have been calculated for the Lithium dimer. ETDMFs are needed in understanding processes like photodissociation, photoassociation, cooling, and trapping of molecules. The results of the four ETDMFs have been obtained...
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Measurements of the rms currents in two phases in a ship power station with two generators operating in parallel
Open Research DataThe presented dataset is part of research focusing on the assessment of metrological properties of the instrument, Estimator/Analyzer (E/A v.2), developed and made at the Faculty of Electrical Engineering, Department of Marine Electrical Power Engineering of Gdynia Maritime University. The attached dataset contains processed data, expressing the rms...
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Electronic transition dipole moment functions of the second triplet Sigma ungerade plus state of the Lithium dimer
Open Research DataElectronic transition dipole moment functions (ETDMF) of the second triplet Sigma ungerade plus (2tSu+) state have been calculated for the Lithium dimer. ETDMFs are needed in understanding processes like photodissociation, photoassociation, cooling, and trapping of molecules. The results of the five ETDMFs have been obtained by the nonrelativistic multireference...
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Electronic transition dipole moment functions of the second singlet Sigma ungerade plus and second triplet Sigma gerade plus states of the Lithium dimer
Open Research DataElectronic transition dipole moment functions (ETDMF) of the second singlet Sigma ungerade plus (2sSu+) and second triplet Sigma gerade plus (2tSg+) states have been calculated for the Lithium dimer. ETDMFs are needed in understanding processes like photodissociation, photoassociation, cooling, and trapping of molecules. The results of the four ETDMFs...
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Electronic transition dipole moment functions of the third singlet Sigma gerade plus state of the Lithium dimer
Open Research DataElectronic transition dipole moment functions (ETDMF) of the third singlet Sigma gerade plus (3sSg+) state have been calculated for the Lithium dimer. ETDMFs are needed in understanding processes like photodissociation, photoassociation, cooling, and trapping of molecules. The results of the five ETDMFs have been obtained by the nonrelativistic multireference...
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Electronic transition dipole moment functions of the first singlet Sigma ungerade plus and first triplet Sigma gerade plus states of the Lithium dimer
Open Research DataElectronic transition dipole moment functions (ETDMF) of the first singlet Sigma ungerade plus (1sSu+) and first triplet Sigma gerade plus (1tSg+) states have been calculated for the Lithium dimer. ETDMFs are needed in understanding processes like photodissociation, photoassociation, cooling, and trapping of molecules. The results of the four ETDMFs...
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Electronic transition dipole moment functions of the third triplet Sigma ungerade plus state of the Lithium dimer
Open Research DataElectronic transition dipole moment functions (ETDMF) of the third triplet Sigma ungerade plus (3tSu+) state have been calculated for the Lithium dimer. ETDMFs are needed in understanding processes like photodissociation, photoassociation, cooling, and trapping of molecules. The results of the five ETDMFs have been obtained by the nonrelativistic multireference...
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Electronic transition dipole moment functions of the fourth triplet Sigma ungerade plus state of the Lithium dimer
Open Research DataElectronic transition dipole moment functions (ETDMF) of the fourth triplet Sigma ungerade plus (4tSu+) state have been calculated for the Lithium dimer. ETDMFs are needed in understanding processes like photodissociation, photoassociation, cooling, and trapping of molecules. The results of the five ETDMFs have been obtained by the nonrelativistic multireference...
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Electronic transition dipole moment functions of the fourth singlet Sigma gerade plus state of the Lithium dimer
Open Research DataElectronic transition dipole moment functions (ETDMF) of the fourth singlet Sigma gerade plus (4sSg+) state have been calculated for the Lithium dimer. ETDMFs are needed in understanding processes like photodissociation, photoassociation, cooling, and trapping of molecules. The results of the five ETDMFs have been obtained by the nonrelativistic multireference...
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Electronic transition dipole moment functions of the first singlet Pi gerade and first triplet Pi gerade states of the Lithium dimer
Open Research DataElectronic transition dipole moment functions (ETDMF) of the first singlet Pi gerade (1sPg) and first triplet Pi gerade (1tPg) states have been calculated for the Lithium dimer. ETDMFs are needed in understanding processes like photodissociation, photoassociation, cooling, and trapping of molecules. The results of the four ETDMFs have been obtained...
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Electronic transition dipole moment functions of the second singlet Sigma gerade plus state of the Lithium dimer
Open Research DataElectronic transition dipole moment functions (ETDMF) of the second singlet Sigma gerade plus (2sSg+) state have been calculated for the Lithium dimer. ETDMFs are needed in understanding processes like photodissociation, photoassociation, cooling, and trapping of molecules. The results of the five ETDMFs have been obtained by the nonrelativistic multireference...
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Electronic transition dipole moment functions of the fifth singlet Sigma gerade plus state of the Lithium dimer
Open Research DataElectronic transition dipole moment functions (ETDMF) of the fifth singlet Sigma gerade plus (5sSg+) state have been calculated for the Lithium dimer. ETDMFs are needed in understanding processes like photodissociation, photoassociation, cooling, and trapping of molecules. The results of the five ETDMFs have been obtained by the nonrelativistic multireference...
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Electronic transition dipole moment functions of the third singlet Sigma ungerade plus and third triplet Sigma gerade plus states of the Lithium dimer
Open Research DataElectronic transition dipole moment functions (ETDMF) of the third singlet Sigma ungerade plus (3sSu+) and third triplet Sigma gerade plus (3tSg+) states have been calculated for the Lithium dimer. ETDMFs are needed in understanding processes like photodissociation, photoassociation, cooling, and trapping of molecules. The results of the four ETDMFs...
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Electronic transition dipole moment functions of the second singlet Pi gerade and second triplet Pi gerade states of the Lithium dimer
Open Research DataElectronic transition dipole moment functions (ETDMF) of the second singlet Pi gerade (2sPg) and second triplet Pi gerade (2tPg) states have been calculated for the Lithium dimer. ETDMFs are needed in understanding processes like photodissociation, photoassociation, cooling, and trapping of molecules. The results of the four ETDMFs have been obtained...
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Electronic transition dipole moment functions of the fifth triplet Sigma ungerade plus state of the Lithium dimer
Open Research DataElectronic transition dipole moment functions (ETDMF) of the fifth triplet Sigma ungerade plus (5tSu+) state have been calculated for the Lithium dimer. ETDMFs are needed in understanding processes like photodissociation, photoassociation, cooling, and trapping of molecules. The results of the five ETDMFs have been obtained by the nonrelativistic multireference...
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Electronic transition dipole moment functions of the first singlet Sigma gerade plus state of the Lithium dimer
Open Research DataElectronic transition dipole moment functions (ETDMF) of the first singlet Sigma gerade plus (1sSg+) state have been calculated for the Lithium dimer. ETDMFs are needed in understanding processes like photodissociation, photoassociation, cooling, and trapping of molecules. The results of the five ETDMFs have been obtained by the nonrelativistic multireference...
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Electronic transition dipole moment functions of the first triplet Sigma ungerade plus state of the Lithium dimer
Open Research DataElectronic transition dipole moment functions (ETDMF) of the first triplet Sigma ungerade plus (1tSu+) state have been calculated for the Lithium dimer. ETDMFs are needed in understanding processes like photodissociation, photoassociation, cooling, and trapping of molecules. The results of the five ETDMFs have been obtained by the nonrelativistic multireference...
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Determination of the ratio resistors in the input circuits of the NTC10k thermistor calibration system
Open Research DataThe presented data set is part of the research aimed at determining the actual characteristics of each thermistor in a package of twenty NTC10k type sensors.
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Wielokryterialna analiza porównawcza lokalizacji źródeł wytwórczych energii elektrycznej
PublicationArtykuł przedstawia ranking lokalizacji czterech źródeł wytwórczych energii elektrycznej: biogazowni rolniczej, biogazowni utylizacyjnej oraz dwóch elektrowni fotowoltaicznych, wykonany przy użyciu połączonych metod Analitycznego Procesu Hierarchicznego (AHP) oraz taksonomii numerycznej. Omówiono zalety połączenia metod, przedstawiono przykład zastosowania oraz wskazano kryteria o największym i najmniejszym wpływie na realizację...
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Detection of Closing Crack in Beam Based on Responses Induced by Harmonic Excitation
PublicationThe non-linear contact model was chosen to simulate the closed crack in the cantilever beam. The study examines the shape and characteristics of the phase diagram of a cantilever beam with closed cracks. It investigates how various crack properties influence the geometry of the phase diagram and proposes a method for identifying cracks based on their features. The area of each closed curve in the phase diagram is determined using...
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Fluid–Structure Interaction methods for the progressive anatomical and artificial aortic valve stenosis
PublicationCardiovascular system diseases, as aortic valve stenosis, are the main cause of mortality and morbidity among patients. There is still a room for enhancement of the diagnostic and therapeutic procedures, which will lead to improvement of the treatment. One of the remedies are the computer tools to support the medical diagnoses and prostheses design. The development of a procedure for modeling the aortic valves: anatomical tricuspid...