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Search results for: DIRECT SHELL FORMULATION
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Planning optimised multi-tasking operations under the capability for parallel machining
PublicationThe advent of advanced multi-tasking machines (MTMs) in the metalworking industry has provided the opportunity for more efficient parallel machining as compared to traditional sequential processing. It entailed the need for developing appropriate reasoning schemes for efficient process planning to take advantage of machining capabilities inherent in these machines. This paper addresses an adequate methodical approach for a non-linear...
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On topology optimization of large deformation contact-aided shape morphing compliant mechanisms
PublicationA topology optimization approach for designing large deformation contact-aided shape morphing compliant mechanisms is presented. Such mechanisms can be used in varying operating conditions. Design domains are described by regular hexagonal elements. Negative circular masks are employed to perform dual task, i.e., to decide material states of each element and also, to generate rigid contact surfaces. Each mask is characterized by...
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Non-standard contact conditions in generalized continua: microblock contact model for a Cosserat body
PublicationGeneralized continuum theories involve non-standard boundary conditions that are associated with the additional kinematic variables introduced in those theories, e.g., higher gradients of the displacement field or additional kinematic degrees of freedom. Accordingly, formulation of a contact problem for such a continuum necessarily requires that adequate contact conditions are formulated for the additional kinematic variables and/or...
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The impact of interactions between polyphenolic antioxidants on the redox-related chemical and biological properties of their mixtures – the extension of food synergy concept.
PublicationThe results of studies indicate that chemopreventive efficiency of isolated phytochemicals is lower than that of polyphenol-rich foods. This discrepancy has been ascribed to the food synergy concept that assumes additive or even synergistic influence of different food ingredients on human health. The results presented in the dissertation made it possible to propose an alternative and innovative explanation of these observations. The...
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Data and knowledge supporting decision-making for the urban Food-Water-Energy nexus
PublicationCities are hubs of innovation and wealth creation, and magnets for an increasing urban population. Cities also face unprecedented challenges in terms of food, water and energy scarcity, and governance and management. Urban environmental issues are no longer problems for experts to address but have become issues of public debate, in which knowledge from multiple sectors is needed to support inclusive governance approaches. Consequently,...
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Numerical analyses of novel prefabricated structural wall panels in residential buildings based on laboratory tests in scale 1:1
PublicationThe paper presents experimental and numerical investigations on novel prefabricated composite building wall panels for residential building constructions. The wall panels were composed of reinforced concrete ribbed elements with the core from the EPS foam as the thermal insulation. The wall panels in the full-scale 1:1 were subjected to vertical loads. In the first step, the experiments were analysed with simple usual static methods....
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Nature-Inspired Driven Deep-AI Algorithms for Wind Speed Prediction
PublicationPredicting wind energy production accurately is crucial for enhancing grid management and dispatching capacity. However, the inherent unpredictability of wind speed poses significant challenges to achieving high prediction accuracy. To address this challenge, this study introduces a novel pre-processing framework that leverages thirteen nature-inspired optimization algorithms to extract and combine Intrinsic Mode Functions (IMFs)...
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Antenna Optimization Using Machine Learning with Reduced-Dimensionality Surrogates
PublicationIn modern times, antenna design has become more demanding than ever. The escalating requirements for performance and functionality drive the development of intricately structured antennas, where parameters must be meticulously adjusted to achieve peak performance. Often, global adjustments to geometry are necessary for optimal results. However, direct manipulation of antenna responses evaluated with full-wave electromagnetic (EM)...
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Net-zero carbon condition in wastewater treatment plants: A systematic review of mitigation strategies and challenges
PublicationThe wastewater sector accounts for up to 7 and 10% of anthropogenic CH4 and N2O emissions, respectively. Nowadays wastewater treatment plants are going through a paradigm shift to approach a net-zero carbon condition. Numerous ongoing measures have taken place to identify the sources of greenhouse gases and minimize the carbon footprint. This paper systematically reviews all known practices leading towards net-zero carbon wastewater...
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System monitoringu odbieraków prądu pojazdów kolejowych w aspekcie bezpieczeństwa i ciągłości ruchu.
PublicationOmówiono metodę monitorowania stanu technicznego odbieraków prądu w oparciu o pomiar uniesienia przewodów jezdnych sieci trakcyjnej w czasie przejazdu pociągu. Opisano konstrukcję i zasadę działania wdrożonego na linii kolejowej pilotażowego stanowiska monitoringu. Przedstawiono metodę analizy i sposób wizualizacji wyników pomiarów. Zastosowany algorytm szacowania siły statycznej odbieraka uwzględnia prędkości pociągu i działanie...
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Odnowa modelu biznesu
PublicationW artykule przedstawiono wyniki badań teoretycznych nad istotą odnowy strategicznej biznesu. Odnowę tę oparto na restauracji ciągu zarządzania strategicznego.
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Immunoanalityka – użyteczne podejście analityczne w badaniach środowiska
PublicationWażnym krokiem w rozwoju bezpośrednich metodyk analitycznych było opracowanie technik immunoanalitycznych. Początkowo znalazły one zastosowanie praktyczne w analityce medycznej a później także w analityce środowiskowej. Dzięki temu możliwe jest ilościowe oznaczenie stosunkowo szerokiego spektrum ksenobiotyków w próbkach charakteryzujących się złożonym składem matrycy bez praco- i czasochłonnego etapu przygotowania tych próbek do...
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The importance of the shape of the protein-water interface of a kinesin motor domain for dynamics of the surface atoms of the protein
PublicationSingle kinesin motor domain immersed in water has been investigated using molecular dynamics. It has been found that local properties of water in solvation shell change along with the nature of neighboring protein surface. However, a detailed analysis leads to the conclusion that the geometrical features of hydrogen bonds and overall structure of kinesin hydration water is not very different from bulk water. The local values of...
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The importance of the shape of the protein–water interface of a kinesin motor domain for dynamics of the surface atoms of the protein
PublicationA single kinesin motor domain immersed in water has been investigated using molecular dynamics. It has been found that local properties of water in the solvation shell change along with the nature of the neighboring protein surface. However, a detailed analysis leads to the conclusion that the geometrical features of hydrogen bonds and overall structure of kinesin hydration water are not very different from bulk water. The local...
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COMPOSITE FOOTBRIDGE - SYNERGY EFFECT IN COOPERATION BETWEEN UNIVERSITIES AND INDUSTRY
PublicationPaper presents conditions of science and industry cooperation in Poland (restrictions, barriers, good practice). A key role in initiation of collaboration between units has financial support. What is also important, it is much easier to create innovative solutions on the base of combining the potential of individuals. That is why many countries all over the world look for innovative solutions using budget funds to support grants...
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The buckling analysis of a cold-formed steel C-sectional column resting on an elastic foundation
PublicationThe paper is focused on stability analysis of different models of steel cold-formed C-section column. The analysed element may be applied as a primary load-bearing member in steel trusses or silo columns. The column can be used as a support for a wall of roof plates made of corrugated sheets. The wall sheeting that restrains the column against buckling may be considered as an elastic foundation. Due to the design solutions the...
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STABILITY AND LOAD BEARING CAPACITY OF A BARS WITH BUILT UP CROSS SECTION AND ELASTIC SUPPORTS
PublicationThe present paper is devoted to the numerical analysis and experimental tests of compressed bars with built–up cross section which are commonly used as a top chord of the roof trusses. The significant impact on carrying capacity for that kind of elements in case of out-of-plane buckling is appropriate choice of battens which are used to provide interaction between separate members. Linear buckling analysis results and nonlinear static...
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Vegetable derived-oil facilitating carbon black migration from waste tire rubbers and its reinforcement effect
PublicationThree dimensional chemically cross-linked polymer networks present a great challenge for recycling and reutilization of waste tire rubber. In this work, the covalently cross-linked networks of ground tire rubber (GTR) were degraded heterogeneously under 150 °C due to the synergistic effects of the soybean oil and controlled oxidation. The degradation mechanism was discussed using Horikx theory and Fourier transformation infrared...
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Two- and three-dimensional elastic networks with rigid junctions: modeling within the theory of micropolar shells and solids
PublicationFor two- and three-dimensional elastic structures made of families of flexible elastic fibers undergoing finite deformations, we propose homogenized models within the micropolar elasticity. Here we restrict ourselves to networks with rigid connections between fibers. In other words, we assume that the fibers keep their orthogonality during deformation. Starting from a fiber as the basic structured element modeled by the Cosserat...
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Modelling of Abdominal Wall Under Uncertainty of Material Properties
PublicationThe paper concerns abdominal wall modelling. The accurate prediction and simulation of abdominal wall mechanics are important in the context of optimization of ventral hernia repair. The shell Finite Element model is considered, as the one which can be used in patient-specific approach due to relatively easy geometry generation. However, there are uncertainties in this issue, e.g. related to mechanical properties since the properties...
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Axial capacity of steel built-up battened columns
PublicationThis paper deals with the numerical investigation aimed to study the axial capacity of pin-ended steel built-up columns. Three methods of calculating forces in chords and batten, taking into account the material and geometric imperfections specified in the Eurocode 3 are considered. The aim of this study was to compare different methods allowing the calculation of the column load capacity and determine a simpler and faster method...
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Truss imperfections in the design of bar and diaphragm bracing systems
PublicationIn the article three variants of roof bracing were considered: bar bracing, diaphragm bracing and the combination of bar and diaphragm bracing. Different analytical and numerical ways of taking into account the imperfections of the truss girder were compared. The entire 3D model of the roof (shell and beam elements with the eccentricities taken into account) was analysed numerically. Selected stressed-skin aspects were considered....
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Dynamic variables limitation for backstepping control of induction machine and voltage source converter
PublicationDynamic variables limitation for backstepping control of induction machine and voltage source converter The paper presents the method of control of an induction squirrel-cage machine supplied by a voltage source converter. The presented idea is based on an innovative method of the voltage source converter control, consisting in direct joining of the motor control system with the voltage source rectifier control system. The combined...
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Lithuania inland waterways links to Western Europe inland waterways network
PublicationLithuania Inland waterways now mainly are used for transportation and tourism within Lithuania tertitory. In the same time difficulties crossing Kaliningrad region and direct Lithuania inland Waterways Buks with Western Europe inland waterway system nowadays are impossible, depending on Russia inland Waterways regulation. New ideas and possibilities of linking Lithuania inland Waterways witki Western Europe inland waterways system...
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Kwadraturowy DDS z ułamkowo-opóźniającym filtrem o strukturze flash-Farrow.
PublicationW pracy omawiamy nieliniowy algorytm cyfrowego generatora z syntezą bezpośrednią, zwanego krótko DDS od ang. Direct Digital Synthesizer. Proponujemy nowy algorytm kwadraturowego DDS. Pozwala on osiągnąć zarówno wysoki stopień czystości generowanej sinusoidy kwadraturowej, jak i bardzo małe błędy modulacji częstotliwości (FM) przy małej pojemności pamięci ROM, od której zależy pobór mocy zasilania. Ponadto proponujemy nowe podejście...
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Measurement and visualization of sound intensity vector distribution in proximity of acoustic diffusers
PublicationIn this work, we would like to present analyses and visualizations of sound intensity distribution measured in proximity of an acoustic diffuser. Such distribution may be used for estimation of basic acoustic parameters of a diffuser. Measurement is performed with the use of a logarithmic sine sweep which allows for the analysis of waves scattered by the diffuser and rejecting the direct sound signal component. Pressure and sound...
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Fast multi-criterial statistical analysis and design optimization of compact microwave couplers
Publication—A rapid statistical analysis and yield estimation of compact microwave couplers involving multiple performance parameters has been presented. The analysis is realized using a fast surrogate model representing appropriate characteristic points of the coupler response. Because of less nonlinear dependence of the characteristic points on the structure geometry (compared to the original response, i.e., S-parameters vs. frequency),...
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Optymalizacja topologiczna części lotniczych
PublicationOstatnie 40 lat to ciągły rozwój przemysłu lotniczego, dzięki któremu możliwe jest wykonywanie bezpiecznych, szybkich oraz ekonomicznych lotów. Projektowanie i budowa nowoczesnych samolotów wymaga jednak wykorzystywania wysoko rozwiniętych metod oraz technologii, dzięki którym możliwe jest sprostanie stawianym przed nimi wymaganiom. EADS Innovation Works, jako organizacja badawczo-technologiczna, jest zaangażowana w rozwój oraz...
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Logistics aspects in the group of health care accreditation standards associated with patient nutrition
PublicationMedical services are currently one of the more popular branches of the service sector, both in Poland and worldwide. Along with direct impact on human health and life, they have influence on the necessity of constant search for forms of their improvement. Actions taken for improvement of health services quality are implemented with diversity, both as an obligatory action imposed in all medical services units, as well as, actions...
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Reliable underwater communication system for shallow coastal waters
PublicationThis paper presents a reliable and robust low data rate spread spectrum approach which is implemented in the acoustic underwater communication system for shallow coastal waters. It shows operation assumptions of spread spectrum techniques based on the wellknown Shannon equation. It describes two methods of spread spectrum: frequency hopping spread spectrum and direct sequence spread spectrum; their block diagram and their characteristics...
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Spectral Methods for Modelling of Wave Propagation in Structures in Terms of Damage Detection—A Review
PublicationModern methods of detection and identification of structural damage direct the activities of scientific groups towards the improvement of diagnostic methods using for example the phenomenon of mechanical wave propagation. Damage detection methods that use mechanical wave propagation in structural components are extremely effective. Many different numerical approaches are used to model this phenomenon, but, due to their universal...
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Trawl-Door Shape Optimization with 3D CFD Models and Local Surrogates
PublicationDesign and optimization of trawl-doors are key factors in minimizing the fuel consumption of fishing vessels. This paper discusses optimization of the trawl-door shapes using high-fidelity 3D computational fluid dynamic (CFD) models. The accurate 3D CFD models are computationally expensive and, therefore, the direct use of traditional optimization algorithms, which often require a large number of evaluations, may be prohibitive....
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Determination of p-y curves for offshore piles based on in-situ soil investigations
PublicationOffshore piles are subjected to complex loads with considerable lateral component. The pile-soil response to lateral loads can be described with the p-y method. For a given depth the load–deflection relationship is built to simulate the surrounding soil stiffness. This state-of-art paper presents a brief discussion of determination methods for the p-y curves using a standard approach based on the soil parameters derived from laboratory...
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2022-2023 - Strenght of materials towards applications, PG_00053661
e-Learning CoursesThe course is mainly dedicated to the DAPE Students. From the theoretical point of view the course consists of the following problems to be discussed during the lectures and exercises: -fundamentals of strength of materials -basic structures and environment -loads on structures -strength of materials: tension, stress, analysis of stress and strain, bending moments and shearing forces, longitudinal and shearing stress in beams,...
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Strenght of materials towards applications , PG_00053661
e-Learning CoursesThe course is dedicated to the DAPE WIMiO Students. From the theoretical point of view the course consists of the following problems to be discussed during the lectures: -fundamentals of strength of materials -basic structures and environment -loads on structures -strength of materials: tension, stress, analysis of stress and strain, bending moments and shearing forces, longitudinal and shearing stress in beams, bending stress...
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Wear in siding friction tests. Ring-on-ring contact. Sintered alumina ceramics (98%). Paraffin oil lubrication. Specim. sets #20-#21, #22-#23, #24-#25, #26-#27, #28-#29,#30 - #31. Run time: 4-8h.
Open Research DataWear in sliding friction tests in ring-on-ring contact. Sintered alumina ceramics (98%) in self-mated contact. Lubrication: paraffin oil. Sliding velocity: 0.2 m/s. Mean contact stress: 10 MPa. Test rig: PT-3 Tribometer.Running time: 4-8h.Specimen sets:Specim. sets (# [upper, rotating] - #[lower, non-rotating]):#20-#21, #22-#23, #24-#25, #26-#27,...
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Specimen running-in. Prep. to sliding friction tests. Ring-on-ring contact. Sintered alumina ceramics (98%). Paraffin oil lubrication. Specimen set #24 - #25.
Open Research DataSpecimen running-in procedure. Preparation to sliding friction tests in ring-on-ring contact. Sintered alumina ceramics (98%) in self-mated contact. Lubrication: paraffin oil. Sliding velocity: 0.2 m/s. Mean contact stress: 10 MPa. Test rig: PT-3 Tribometer. Specimen set #24 (upper, rotating), #25 (lower, non-rotating)CZ_PRZYS.MAT - accelerometerMOM_TAR.MAT...
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Specimen running-in. Prep. to sliding friction tests. Ring-on-ring contact. Sintered alumina ceramics (98%). Paraffin oil lubrication. Specimen set #28 - #29.
Open Research DataSpecimen running-in procedure. Preparation to sliding friction tests in ring-on-ring contact. Sintered alumina ceramics (98%) in self-mated contact. Lubrication: paraffin oil. Sliding velocity: 0.2 m/s. Mean contact stress: 10 MPa. Test rig: PT-3 Tribometer. Specimen set #28 (upper, rotating), #29 (lower, non-rotating)CZ_PRZYS.MAT - accelerometerMOM_TAR.MAT...
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Wear in siding friction tests. Ring-on-ring contact. Sintered alumina ceramics (98%). Paraffin oil lubrication. Specim. sets #20-#21, #22-#23, #24-#25, #26-#27, #28-#29,#30 - #31. Run time: 0-4h.
Open Research DataWear in sliding friction tests in ring-on-ring contact. Sintered alumina ceramics (98%) in self-mated contact. Lubrication: paraffin oil. Sliding velocity: 0.2 m/s. Mean contact stress: 10 MPa. Test rig: PT-3 Tribometer.Running time: 0 - 4h.Specimen sets:Specim. sets (# [upper, rotating] - #[lower, non-rotating]):#20-#21, #22-#23, #24-#25, #26-#27,...
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Specimen running-in. Prep. to sliding friction tests. Ring-on-ring contact. Sintered alumina ceramics (98%). Paraffin oil lubrication. Specimen set #30 - #31.
Open Research DataSpecimen running-in procedure. Preparation to sliding friction tests in ring-on-ring contact. Sintered alumina ceramics (98%) in self-mated contact. Lubrication: paraffin oil. Sliding velocity: 0.2 m/s. Mean contact stress: 10 MPa. Test rig: PT-3 Tribometer. Specimen set #30 (upper, rotating), #31 (lower, non-rotating)CZ_PRZYS.MAT - accelerometerMOM_TAR.MAT...
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Specimen running-in. Prep. to sliding friction tests. Ring-on-ring contact. Sintered alumina ceramics (98%). Paraffin oil lubrication. Specimen set #20 - #21.
Open Research DataSpecimen running-in procedure. Preparation to sliding friction tests in ring-on-ring contact. Sintered alumina ceramics (98%) in self-mated contact. Lubrication: paraffin oil. Sliding velocity: 0.2 m/s. Mean contact stress: 10 MPa. Test rig: PT-3 Tribometer. Specimen set #20 (upper, rotating), #21 (lower, non-rotating)CZ_PRZYS.MAT - accelerometerMOM_TAR.MAT...
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Specimen running-in. Prep. to sliding friction tests. Ring-on-ring contact. Sintered alumina ceramics (98%). Paraffin oil lubrication. Specimen set #22 - #23.
Open Research DataSpecimen running-in procedure. Preparation to sliding friction tests in ring-on-ring contact. Sintered alumina ceramics (98%) in self-mated contact. Lubrication: paraffin oil. Sliding velocity: 0.2 m/s. Mean contact stress: 10 MPa. Test rig: PT-3 Tribometer. Specimen set #22 (upper, rotating), #23 (lower, non-rotating)CZ_PRZYS.MAT - accelerometerMOM_TAR.MAT...
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Specimen running-in. Prep. to sliding friction tests. Ring-on-ring contact. Sintered alumina ceramics (98%). Paraffin oil lubrication. Specimen set #28 - #29.
Open Research DataSpecimen running-in procedure. Preparation to sliding friction tests in ring-on-ring contact. Sintered alumina ceramics (98%) in self-mated contact. Lubrication: paraffin oil. Sliding velocity: 0.2 m/s. Mean contact stress: 10 MPa. Test rig: PT-3 Tribometer. Specimen set #28 (upper, rotating), #29 (lower, non-rotating)CZ_PRZYS.MAT - accelerometerMOM_TAR.MAT...
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Specimen running-in. Prep. to sliding friction tests. Ring-on-ring contact. Sintered alumina ceramics (98%). Paraffin oil lubrication. Specimen set #26 - #27.
Open Research DataSpecimen running-in procedure. Preparation to sliding friction tests in ring-on-ring contact. Sintered alumina ceramics (98%) in self-mated contact. Lubrication: paraffin oil. Sliding velocity: 0.2 m/s. Mean contact stress: 10 MPa. Test rig: PT-3 Tribometer. Specimen set #26 (upper, rotating), #27 (lower, non-rotating)CZ_PRZYS.MAT - accelerometerMOM_TAR.MAT...
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Switched-capacitor DC-DC converters in arbitrary switching mode - topologically derived resistive models based on incremental graph approach.
PublicationIn the preceding paper we reviewed some of modeling approaches aimed at systematic formulation and solution of switched capacitor DC-DC converters. In our review, special attention was paid to computationally efficient and mathematically elegant methods. In so doing we had tried to demonstrate the virtues of unified Incremental Graph (IG) approach. Incremental Graph is, in concept, a tool originally created for analysis and synthesis...
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A new approach to determination of the two-mass model parameters of railway current collector
PublicationThe paper presents two mathematical models of railway current collectors both with two degrees of freedom. The first one, hereinafter Pantograph Articulated Model (PAM), has one degree of freedom in rotational motion and the second degree of freedom in translational motion. The second model, called henceforth as Pantograph Reference Model (PRM), has both degrees of freedom in translational motion. Differential equations of the...
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A new approach to determination of the two-mass model parameters of railway current collector
PublicationThe paper presents two mathematical models of railway current collectors both with two degrees of freedom. The first one, hereinafter Pantograph Articulated Model (PAM), has one degree of freedom in rotational motion and the second degree of freedom in translational motion. The second model, called henceforth as Pantograph Reference Model (PRM), has both degrees of freedom in translational motion. Differential equations of the...
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Modelling tunnelling-induced deformation in stiff soils with a hyperelastic–plastic anisotropic model
PublicationIn this paper, the tunnelling-induced deformation in anisotropic stiff soils is analysed using FE modelling. The influence of material description is investigated rather than an advanced simulation of the tunnelling method. A new hyperelastic– plastic model is proposed to describe the anisotropic mechanical behaviour of stiff highly overconsolidated soil. This model can reproduce the superposition of variable stress-induced anisotropy...
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Hidden Tensor Structures
PublicationAny single system whose space of states is given by a separable Hilbert space is automatically equipped with infinitely many hidden tensor-like structures. This includes all quantum mechanical systems as well as classical field theories and classical signal analysis. Accordingly, systems as simple as a single one-dimensional harmonic oscillator, an infinite potential well, or a classical finite-amplitude signal of finite duration...
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Design and Microwave-Assisted Synthesis of TiO2-Lanthanides Systems and Evaluation of Photocatalytic Activity under UV-LED Light Irradiation
PublicationThe TiO2-Eu and TiO2-La systems were successfully synthesized using the microwave method. Based on the results of X-ray diffraction analysis, it was found that regardless of the analyzed systems, two crystal structures were noted for the obtained samples: anatase and rutile. The analysis, such as XPS and EDS, proved that the doped lanthanum and europium nano-particles are present only on the TiO2 surface without disturbing the...