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Search results for: geometria zawieszenia
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Experiments on Preserving Pieces of Information in a Given Order in Holographic Reduced Representations and the Continuous Geometric Algebra Model
PublicationGeometric Analogues of Holographic Reduced Representations (GAc, which is the continuous version of the previously developed discrete GA model) employ role-filler binding based on geometric products.Atomic objects are real-valued vectors in n-dimensional Euclidean space and complex statements belong to a hierarchy of multivectors. The property of GAc and HRR studied here is the ability to store pieces of information in a given...
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A comparison of geometric analogues of holographic reduced representations, original holographic reduced representations and binary spatter codes
PublicationGeometric Analogues of Holographic Reduced Representations (GA HRR) employ role-filler binding based on geometric products. Atomic objects are real-valued vectors in n-dimensional Euclidean space and complex statements belong to a hierarchy of multivectors. The paper reports a battery of tests aimed at comparison of GA HRR with Holographic Reduced Representation (HRR) and Binary Spatter Codes (BSC). Firstly, we perform a test of...
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Divination from chips: monitoring of the sawing process with chip geometry analyzes
PublicationWióry (trociny) są niechcianym produktem towarzyszącym procesowi przecinania. Jednakże, niosą one w sobie wiele informacji świadczących o przebiegu procesu obróbki. Metoda oceny składu procentowego wiórów - ich frakcji - jest prosta lecz ma szereg ważnych ograniczeń. W pracy zaprezentowano nowy alternatywny sposób pomiaru geometrii wiórów. Przedstawiono wyniki dla skrawania drewna mrożonego i nie mrożonego. Wyniki uzyskane ta metodą...
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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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High accuracy multisensor hydroacoustic system for models of trawl geometry measurements
PublicationW pracy przedstawiono wieloelementowy hydroakustyczny system do pomiaru modeli włoków. System został zaprojektowany dla Akademii Rolniczej w Szczecinie i umożliwia precyzyjny pomiar geometrii projektowanych tam narzędzi połowowych w tym selektywnych worków dorszowych. Zastosowanie małych hydrofonów o wysokiej częstotliwości pracy oraz cyfrowego przetwarzania sygnałów z analizą korelacyjną umożliwiło uzyskanie bardzo dużej dokładności...
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Experimental and numerical study on stability loss of innovative geometry steel girder
PublicationThis paper presents the experimental and numerical analysis of an innovative plate girder geometry with variable web thicknesses. An idea proposed in this research is to increase the stability of the girder web by increasing its thickness in the compressed zone. This solution can replace commonly used longitudinal stiffeners which are designed to prevent web local loss of stability. Moreover, such an innovative approach requires...
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Neural Network Application for Recognition of Geometry Degradation of Power Cycle Components
PublicationPrzedyskutowano problem rozpoznawania degradacji geometrycznej. Skuteczne zastosowanie wybranego typu sieci neuronowej (SSN) jest prezentowane w referacie. SSN wykrywająca typy degradacji geometrycznej wykazała wysoką jakość. Pokazano pewną możliwość ekstrapolacji takich SSN. Pokazano możliwość wykrywania typów degradacji geometrycznej nawet w przypadku pozyskiwania niepełnych danych pomiarowych.
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Geometry Parametric Model Order Reduction with Randomly Generated Projection Bases
PublicationIn this work, a reduced-order model for geometry parameters and fast frequency sweep is proposed. The Finite Element Method is used to solve time-harmonic Maxwell’s equations. Taking into account the electromagnetic field does not arbitrarily vary as a function of frequency and geometry parameters, a low dimension system manifold is identified. Thus, the original Finite Element problem can be approximated by a model of reduced...
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Influence of ducting geometry on working parameters of pipe type hydraulic turbines
PublicationMała energetyka wodna. Omówiono własności użytkowe - głównie, sprawność i adaptacyjność - uzyskiwane poprzez rozwiązania układów turbinowych stosowanych w obszarze zagospodarowywania piętrzeń niskospadowych. Wskazano przyczyny od których te własności zależą. Pokazano też przykład rozwiązania o pożądanych własnościach dla zagospodarowywania obiektów w mało atrakcyjnym ekonomicznie obszarze piętrzeń najniższych.
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Impact of rotor geometry optimization on the off-design ORC turbine performance
PublicationThe paper describes the method of CFD based Nelder-Mead optimization of a 10 kW single-stage axial turbine operating in an ORC system working on R7100. The total-to-static isentropic efficiency is defined as an objective function. Multi-point linear regression is carried out to determine the significance of the objective function arguments and to pick up the set of particular variables and characteristic quantities (e.g. flow angles)...
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Preparatory Railway Track Geometry Estimation Based on GNSS and IMU Systems
PublicationThe article discusses an important issue of railway line construction and maintenance, which fundamentally is the verification of geometric parameters of the railway track. For this purpose, mobile measurements have been performed using a measuring platform with two properly arranged GNSS receivers, which made it possible to determine the base vector of the platform. The measuring functionality of the system was extended by IMU....
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Optimized Stress and Geometry Control of Spherical structures under Lateral Loadings
PublicationIn this paper, a numerical model of a double-layer spherical structure has been examined under lateral loadings. When the structure has been distorted due to loadings, the dislocated joints have been moved to their original positions utilizing the adjustment techniques based on the force method. Meanwhile, the members’ internal forces were kept in the desired domain. Optimization techniques were also implemented in order to minimalize...
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Fast geometry scaling of miniaturized microwave couplers with power split correction
PublicationRedesigning a microwave circuit for various operating conditions is a practically important yet challenging problem. The purpose of this article is development and presentation of a technique for fast geometry scaling of miniaturized microwave couplers with respect to operating frequency. Our approach exploits an inverse surrogate model constructed using several reference designs that are optimized for a set of operating frequencies...
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Electrostatic Zipping Actuators—Analysis of the Pull-In Effect Depending on the Geometry Parameters
PublicationContinuous work on a new generation of actuators, referred to as artificial muscles, resulted in the initiation of work on electrostatic zipping actuators, the concept of which is derived from micro electro-mechanical devices. Despite partial knowledge of their basic operating parameters, a question remains whether electrostatic zipping actuators are able to meet the expectations in the context of generated forces and control possibilities....
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Computer-aided evaluation of the railway track geometry on the basis of satellite measurements
PublicationIn recent years, all over the world there has been a period of intensive development of GNSS (Global Navigation Satellite Systems) measurement techniques and their extension for the purpose of their applications in the field of surveying and navigation. Moreover, in many countries a rising trend in the development of rail transportation systems has been noticed. In this paper, a method of railway track geometry assessment based...
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Application of 3D printing metal powder technology in the manufacture of components with complex geometries
PublicationThe possibilities of using 3D printing powder technologies for making objects with complex geometries were presented. For this purpose, selected examples of elements with different geometries were used, which were built using metal powder methods – DMLS (direct metal laser sintering) / SLM (selective laser melting). Simultaneously, the indicated elements concern those areas of industry where 3D printing technology has been widely...
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Mapping Mechanostable Pulling Geometries of a Therapeutic Anticalin/CTLA-4 Protein Complex
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Effect of the Geometrical Shape of a Partition on the Natural Convection of Two Fluids in a Separated Cavity
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Influence of geometrical and operational parameters on tooth wear in the working mechanism of a satellite motor
PublicationThis article describes the phenomena affecting the wear of the rotor of the working mechanism in a hydraulic satellite motor. The basic geometrical relationships that allow the calculation of the coordinates of the points of contact between the satellite and the rotor and the curvature are presented. A method for calculating the number of contacts of the satellite teeth with the rotor teeth and of the satellite teeth with the curvature...
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Modelling of Curvature of the Railway Track Geometrical Layout Using Particle Swarm Optimization
PublicationA method of railway track geometrical layout design, based on application of cubic C-Bezier curves for describing the layout curvature is presented in the article. The control points of a cubic C-Bezier curve are obtained in an optimization process carried out using Particle Swarm Optimization algorithm. The optimization criteria are based on the evaluation of the dynamic interactions and satisfaction of geometrical design requirements.
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The process of identification of the track's geometrical layout and the alignment project based on the of satellite measurements
PublicationIn the paper a methodology of restoring of railway track’s geometrical shape in a horizontal plane on the base of conducted mobile satellite surveying was presented. The authors proposed a calculating algorithm for designing the track sections placed in horizontal arcs. In the algorithm an analytical methodology with mathematical formulas is applied. The procedure has an universal character, i.e. provides the possibility of varying...
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3D modelling of liquid fuels base infrastructure for the purpose of visualization and geometrical analysis
PublicationThe paper presents the methodology for obtaining a 3D model of the tank for liquid fuels on the basis of the terrestrial laser scanning and its processing for the analysis of tanks geometry. The development process indicates the possibility to obtain the reliable results useful for the evaluation of the tank side surfaces geometry (shells). The result of the development is a 3D model of the tank, taking into account the individual...
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Optimizing the process of railway geometrical layout designing with multi-criteria assessment method
PublicationThe paper presents the main assumptions of the Multi-criteria assessment method used in process of upgrading the railway geometrical layout. The advantages of metaheuristic search were described. The criteria influencing the investment were defined. The fitness function used in the analysis was described. The example of using the optimization algorithm with the help of self developed computer software was described.
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Accuracy assessment of mobile satellite measurements in relation to the geometrical layout of rail tracks
PublicationThe paper presents the campaigns of mobile satellite measurements, carried out in 2009–2015 on the railway and tram lines. The accuracy of the measurement method has been analysed on the basis of the results obtained in both horizontal and vertical planes. The track axis deviation from the defined geometric shape has been analysed in the areas clearly defined in terms of geometry, i.e. on the straight sections and sections with...
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DIFFERENTIAL GEOMETRY AND ITS APPLICATIONS
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International Electronic Journal of Geometry
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Journal of Geometry and Symmetry in Physics
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Analysis and Geometry in Metric Spaces
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Eurographics Symposium on Geometry Processing
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Proceedings of the International Geometry Center
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ANNALS OF GLOBAL ANALYSIS AND GEOMETRY
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ANALIZA KONSTRUKCJI I GEOMETRII ŁOŻYSK WZDŁUŻNO-POPRZECZNYCH TURBOSPRĘŻARKI A1.3001 typ 3M65 KONCEPCJA ZMODERNIZOWANEGO ŁOŻYSKA.
PublicationW wyniku rozpoznania problemu niezadowalającej trwałości łożysk wałka I i II stopnia turbosprężarki oraz wykonaniu analizy obliczeniowej wielu wariantów łożysk promieniowych i osiowych zaproponowano nowe koncepcje łożysk, które odpowiednio zaprojektowane i wykonane powinny zapewnić długotrwałą pracę.
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Wykorzystanie sieci nieuronowych do przyspieszenia przepływowych obliczeń numerycznych - wybór geometrii wieńca kierowniczego turbiny parowej
PublicationReferat stanowi wprowadzenie do dalszych prac nad rozprawą doktorską. W referacie przedstawiono problem wyboru geometrii wieńca kierowniczego turbiny parowej do dalszych obliczeń. Pokazano kryteria według których dokonywano wyboru spośród różnych typów geometrii.Krótko scharakteryzowano poszczególne typy wieńców turbinowych: wieńce z łopatkami typu PLK,wieńce z łopatkami typu PKH, stopnie reakcyjne oraz ostatnie stopnie części...
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Wyznaczenie obciążeń wiatrem dla budynku wysokiego o złożonej geometrii z wykorzystaniem analizy przepływu CFD
PublicationW pracy poruszono tematykę wykorzystania analizy przepływu CFD do wyznaczenia obciążeń wiatrem dla budynku wysokiego o złożonej geometrii przestrzennej. Przedstawione wyniki obliczeń analitycznych dla budynku wysokiego porównano z wynikami obliczeń numerycznych wykonanych w programie R-Wind Simulation. Dokonano analizy optymalizacji geometrycznej kształtu budynku w zakresie wpływu kąta skrętu (modyfikacja typu makro) i zaokrąglenia/fazowania...
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Wpływ geometrii, właściwości magnetycznych oraz sposobu magnesowania próbki na rozkład przestrzenny magnetycznego pola rozproszonego
PublicationPraca dotyczy problematyki wpływu wybranych czynników na rozkład przestrzenny magnetycznego pola rozproszonego (MPR). Na podstawie wyników badań uzyskanych dla próbek charakteryzujących się przewężeniem i lokalnym spadkiem przenikalności magnetycznej (spowodowanym deformacją plastyczną) stwierdzono, iż oba czynniki wywierają podobny wpływ na rozkład przestrzenny MPR. Na bazie analizy wyników pomiarów MPR oraz symulacji wykonanych...
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Określenie parametrów modelowania geometrii krzyżownic rozjazdów zwyczajnych dla potrzeb budowy i utrzymania linii kolejowych
PublicationZdecydowana większość rozjazdów występująca na liniach kolejowych w Polsce to rozjazdy zwyczajne o typowym zestawie parametrów. Z tego powodu analiza przypadków nietypowych (takich jak rozjazdy o zmiennej krzywiźnie toru zwrotnego) może być utrudniona. Wirtualny model geometryczno-konstrukcyjny rozjazdu, generowany w oparciu o metody analityczne, stanowić może narzędzie użyteczne w sferze projektowania, konstrukcji oraz diagnostyki...
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INTERNATIONAL JOURNAL OF GEOMETRIC METHODS IN MODERN PHYSICS
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Relationship between electronic structure and geometry of silanethiols and their derivatives. Elucidation of copper group silanethiolates
PublicationWyznaczono strukturę elektronową wybranych silanotioli X3SiSH (dla X=H, C2H5, OCH3, F, Cl i Br) oraz powstalych z nich anionów. Geometrię i funkcje falowe wyznaczono przy użyciu teorii funcjonałów gęstości elektronowej DFT. Przeanalizowano wpływ efektów anomerycznych oraz wielkości calki nakładania sigma(Si-S) na obserwowane skrócenie wiązania Si-S przy deprotonowaniu silanotioli. Podano nowe wyjaśnienie wyjątkowo niskiej kwasowości...
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A SEARCH OF AN INDUCER GEOMETRY THAT IS BENEFICIAL FOR LIFTING PARAMETERS OF A LIFTED OBJECT OF A SELECTED SHAPE
PublicationThe literature describes acoustic levitation phenomena with the utilization of air squeeze film between the vibrating inducer and the lifted object. The objective of the study is to determine the shape of the inducer with vibration characteristics that would allow the levitation of an object of the assumed geometry. In this paper, the influence of the dimension ratio of the inducer on the frequency of the first mode of vibration...
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Influence of geometry and annealing temperature in argon atmosphere of TiO2 nanotubes on their electrochemical properties
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Inverse surrogate models for fast geometry scaling of miniaturized dual-band couplers
PublicationRe-design of microwave structures for various sets of performance specifications is a challenging task, particularly for compact components where considerable electromagnetic (EM) cross-couplings make the relationships between geometry parameters and the structure responses complex. Here, we address geometry scaling of miniaturized dual-band couplers by means of inverse surrogate modeling. Our approach allows for fast estimation...
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Expedited Geometry Scaling of Compact Microwave Passives by Means of Inverse Surrogate Modeling
PublicationIn this paper, the problem of geometry scaling of compact microwave structures is investigated. As opposed to conventional structures (i.e., constructed using uniform transmission lines), re-design of miniaturized circuits (e.g., implemented with artificial transmission lines, ATSs) for different operating frequencies is far from being straightforward due to considerable cross-couplings between the circuit components. Here, we...
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THE METHOD OF MEASURING THE MEMBRANE COVER GEOMETRY USING LASER SCANNING AND SYNCHRONOUS PHOTOGRAMMETRY
PublicationThe authors present the experience and results of field studies carried out at the technical acceptance of Forest Opera (name in Polish: Opera Leśna) in Sopot (Poland). An unusual design of covering made in the form of “Sheerfill I” technical fabric membrane required spanned in the form of sails, required the use of terrestrial laser scanning. Such approach allowed for the fast and accurate record of the surface of individual panels...
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Inverse surrogate modeling for low-cost geometry scaling of microwave and antenna structures
PublicationPurpose–The purpose of this paper is to investigate strategies for expedited dimension scaling ofelectromagnetic (EM)-simulated microwave and antenna structures, exploiting the concept of variable-fidelity inverse surrogate modeling.Design/methodology/approach–A fast inverse surrogate modeling technique is described fordimension scaling of microwave and antenna structures. The model is established using referencedesigns obtained...
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Geometry optimization of steroid sulfatase inhibitors - the influence on the free binding energy with STS
PublicationIn the paper we review the application of two techniques (molecular mechanics and quantum mechanics) to study the influence of geometry optimization of the steroid sulfatase inhibitors on the values of descriptors coded their chemical structure and their free binding energy with the STS protein. We selected 22 STS-inhibitors and compared their structures optimized with MM+, PM7 and DFT B3LYP/6–31++G* approaches considering separately...
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Extended duration running and impulse loading characteristics of an acoustic bearing with enhanced geometry
PublicationThis paper presents performance during prolonged running of the acoustic bearing when PZTs are switched off and when they are switched on. The effect of active PZT on shaft’s displacements in X and Y directions is clearly demonstrated. Performance of the acoustic bearing was also assessed when an impulse force was applied to the running shaft at speed. Once again the benefits of having PZTs active are beyond doubt. The instability...
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Bożena Kotarska-Lewandowska dr inż.
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How much a geometrical model of a honeycomb seal can be simpli ed in the CFD calculation
PublicationThis paper presents the inuence of geometry simplication on the results obtained in the computational fluid dynamics simulation. The subject of simulation was part of the honeycomb seal located at the inlet to high pressure part of a steam turbine. There were three different geometrical models assumed in the calculations. First one was two-dimensional case and two others were three dimensional, one with the radius of curvature...
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Techniki zwiększania efektywności metody elementów skończonych poprzez redukcję dziedziny obliczeniowej z wykorzystaniem własności geometrii struktur
PublicationWspółczesna elektronika ze względu na swój szybki rozwój wymaga od nas efektywnego modelowania zjawisk polowych. Celem rozprawy jest zwiększanie efektywności metody elementów skończonych poprzez redukcję dziedziny obliczeniowej z wykorzystaniem własności geometrii struktur oraz jej hybrydyzację z użyciem technik analitycznych. Rozprawa zawiera przegląd stanu wiedzy na temat dostępnych obecnie technik modelowania jak również opis...
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The geometry of free-standing titania nanotubes as a critical factor controlling their optical and photoelectrochemical performance
PublicationTitanium dioxide nanotubes are regarded as one of the most important functional materials and due to their unique electronic properties, chemical stability and photocorrosion resistance, they find applications in, for example, highly efficient photocatalysis or perovskite solar cells. Nevertheless, modification of TiO2 nanotubes is required to overcome their main drawback, i.e. large energy bandgap (>3.2 eV) limiting their ability...