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Search results for: NONLINEAR CONTACT FORCE
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TiN coating in ring-on-ring sliding with distlled water lubrication 5MPa, 0.1m/s specimn. #A45/#A47
Open Research DataWear tests in sliding friction of TiN coating on 1.4021 (EN 10088-1) heat treated stainless steel. Ring - on - ring contact in unidirectional sliding, TiN over TiN. Mean contact stress: 5MPa. Sliding velocity: 0,1 m/s. Mean friction radius: 9.5mm. Lubricant: DISTILLED WATER. Tribometer: PT-3. Overall test time till coating penetration 20 min. The test...
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TiN coating in ring-on-ring sliding with distlled water lubrication 5MPa, 0.1m/s specimn. #A45/#B45
Open Research DataWear tests in sliding friction of TiN coating on 1.4021 (EN 10088-1) heat treated stainless steel. Ring - on - ring contact in unidirectional sliding, TiN over TiN. Mean contact stress: 5MPa. Sliding velocity: 0,1 m/s. Mean friction radius: 9.5mm. Lubricant: DISTILLED WATER. Tribometer: PT-3. Overall test time till coating penetration 90 min. The test...
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Efficiency of acoustic heating produced in the thermoviscous flow of a fluid with relaxation
PublicationInstantaneous acoustic heating of a fluid with thermodynamic relaxation is the subject of investigation. Among others, viscoelastic biological media described by the Maxwell model of the viscous stress tensor, belong to this type of fluid. The governing equation of acoustic heating is derived by means of the special linear combination of conservation equations in differential form, allowing the reduction of all acoustic terms in...
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Impacts in case of triple unilaterally constrained system
PublicationThe this paper focus on the behaviour of a “rigid” body biting into another “rigid” body, with some nonzero relative velocity. In the presently considered case, the introduced collision appears between a selected element of a multibody structure and its reference body being interpreted as the motionless ground. Instead of the classic case, described in a number of dissertations, where a single impacting contact is considered, three...
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Mixed 4-node shell element with assumed strain and stress in 6-parameter theory
PublicationWe propose a mixed hybrid 4-node shell elements based on Hu-Washizu principle. Apart from displacements both strains and stress fields are treated as independent fields. The element is derived in the framework of a general nonlinear 6-field shell theory with drilling rotation which is dedicated to the analysis of multifold irregular shells with intersections. The novelty of the presented results stems from the fact that the measures...
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Asynchronous time difference of arrival (ATDOA) method
PublicationA new method for a location service in the asynchronous wireless sensor networks is outlined. This method, which is called asynchronous time difference of arrival (ATDOA), enables calculation of the position of a mobile node without knowledge of relative time differences (RTDs) between measuring sensors. The ATDOA method is based on the measurement of time difference of arrival between the node and the same sensor at the discrete...
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Method of lines for Hamilton-Jacobi functional differential equations.
PublicationInitial boundary value problems for nonlinear first order partial functional differential equations are transformed by discretization in space variables into systems of ordinary functional differential equations. A method of quasi linearization is adopted. Suffcient conditions for the convergence of the method of lines and error estimates for approximate solutions are presented. The proof of the stability of the diffrential difference...
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Mixed 4-node shell element with assumed strain and stress in 6-parameter theory
PublicationWe propose a mixed hybrid 4-node shell elements based on Hu-Washizu principle. Apart from displacements both strains and stress fields are treated as independent fields. The element is derived in the framework of a general nonlinear 6-field shell theory with drilling rotation which is dedicated to the analysis of multifold irregular shells with intersections. The novelty of the presented results stems from the fact that the measures...
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Mitigation effect of face shield to reduce SARS-CoV-2 airborne transmission risk: Preliminary simulations based on computed tomography
PublicationWe aimed to develop a model to quantitatively assess the potential effectiveness of face shield (visor) in reducing airborne transmission risk of the novel coronavirus SARS-CoV-2 during the current COVID-19 pandemic using the computational fluid dynamics (CFD) method. The studies with and without face shield in both an infected and healthy person have been considered in indoor environment simulation. In addition to the influence...
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Potentiometric sensor with lipid-polymer membranes for quality assessment of French red wines
PublicationThe quality of wines resulting from vineyard management is important for consumers due to the taste and price of wines. In this work, the quality of red wines of three vintages has been investigated by potentiometric sensors with six all-solid-state electrodes. Two series of experiments were carried out. The first involved a qualitative analysis of wine of different vintages from freshly opened bottles. The second consisted of...
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Mitigation effect of face shield to reduce SARS-CoV-2 airborne transmission risk: Preliminary simulations based on computed tomography
PublicationWe aimed to develop a model to quantitatively assess the potential effectiveness of face shield (visor) in reducing airborne transmission risk of the novel coronavirus SARS-CoV-2 during the current COVID-19 pandemic using the computational fluid dynamics (CFD) method. The studies with and without face shield in both an infected and healthy person have been considered in indoor environment simulation. In addition to the influence...
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Dimensioning of vortex storm overflows
PublicationVortex flow control can be made as a rotational chamber, where the centrifugal force is a supporting factor. The paper presents a simplified, but experimentally verified, method of such device designing.
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Role of the Solvation Water in Remote Interactions of Hyperactive Antifreeze Proteins with the Surface of Ice
PublicationMost protein molecules do not adsorb onto ice, one of the exceptions being so-called antifreeze proteins. In this paper, we describe that there is a force pushing an antifreeze protein molecule away from the ice surface when it is not oriented with its ice-binding plane toward the ice and that this pushing force may be also present even when the protein is oriented with its ice-binding plane toward the ice. This force is absent...
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Probabilistic seismic assessment of RC box-girder highway bridges with unequal-height piers subjected to earthquake-induced pounding
PublicationThis paper uses the probabilistic seismic assessment to study the effects of pounding and irregularity on the seismic behavior of typical concrete box-girder bridges with four levels of altitudinal irregularity. To extend the results for all bridges in the same class, uncertainty related to the earthquake, structural geometries, and materials are considered. Pounding is likely to take place in two cases: the first one concerns...
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The E-Cohomological Conley Index, Cup-Lengths and the Arnold Conjecture on T 2n
PublicationWe show that the E-cohomological Conley index, that was introduced by the first author recently, has a natural module structure. This yields a new cup-length and a lower bound for the number of critical points of functionals on Hilbert spaces. When applied to the setting of the Arnold conjecture, this paves the way to a short proof on tori, where it was first shown by C. Conley and E. Zehnder in 1983.
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Crack Mouth Opening Displacement for EH36 Shipbuilding Steel Measurements
PublicationThe dataset titled EH36 steel for shipbuilding (plate thicnkness 50mm) - CMOD - force record, a0/W = 0.6 contains CMOD (Crack Mouth Opening Displacement) - Force record which is the base for evaluation of fracture toughness of structural steel. Bend specimens witch Bx2B section (B= 50mm), and relative initial crack length a0 / W = 0.60 were used. The test was carried out at ambient temperature in accordance to ISO 12135 standard....
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Designing a ship course controller by applying the adaptivebackstepping method
PublicationThe article discusses the problem of designing a proper and efficient adaptive course-keeping control system for a seagoingship based on the adaptive backstepping method. The proposed controller in the design stage takes into account thedynamic properties of the steering gear and the full nonlinear static maneuvering characteristic. The adjustable parametersof the achieved nonlinear control structure were tuned up by using the...
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On the Nonlinea Distortions of Sound and its Coupling with Other Modes in a Gasesous Plasma with Finite Electric Conductivity in a Magnetic Field
PublicationNonlinear phenomena of the planar and quasi-planar magnetoacoustic waves are considered. We focus on deriving of equations which govern nonlinear excitation of the non-wave motions by the intense sound in initially static gaseous plasma. The plasma is treated as an ideal gas with finite electrical conductivity permeated by a magnetic field orthogonal to the trajectories of gas particles. This introduces dispersion of a flow. Magnetoacoustic...
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Robust Model Predictive Control for Autonomous Underwater Vehicle–Manipulator System with Fuzzy Compensator
PublicationThis paper proposes an improved Model Predictive Control (MPC) approach including a fuzzy compensator in order totrack desired trajectories of autonomous Underwater Vehicle Manipulator Systems (UVMS). The tracking performancecan be affected by robot dynamical model uncertainties and applied external disturbances. Nevertheless, the MPCas a known proficient nonlinear control approach should be improved by the...
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Evaluation of pounding effects between reinforced concrete frames subjected to far-field earthquakes in terms of damage index
PublicationIn this paper, three different damage indexes were used to detect nonlinear damages in two adjacent Reinforced Concrete (RC) structures considering pounding effects. 2-, 4- and 8-story benchmark RC Moment Resisting Frames (MRFs) were selected for this purpose with 60%, 75%, and 100% of minimum separation distance and also without any in-between separation gap. These structures were analyzed using the incremental dynamic analysis...
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Simplified, multiregional fuzzy model of a nuclear power plant steam turbine
PublicationPower systems, including steam turbines and synchronous generators, are complex nonlinear systems with parameters varying over time. The paper presents the developed simplified, multiregional fuzzy model of the steam turbine of a nuclear power plant turbine generator set and compares the results with a full nonlinear model and commonly used linear input-output model of a steam turbine. The proposed model consist of series of linear...
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Hysteresis curves for some periodic and aperiodic perturbations in magnetosonic flow
PublicationA thermodynamic relation between perturbations of pressure and mass density in the magnetohydrodynamic flow is theoretically studied. Planar magnetohydrodynamic perturbations with the wave vector, which forms a constant angle with the equilibrium magnetic field, are under study. The theory considers thermal conduction of a plasma and the deviation from adiabaticity of a flow due to some kind of heating–cooling function. It also...
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Microstructure of cross-sections of samples after laser treatment for the article entitled "Mechanical and corrosive properties of Ti13Nb13Zr alloy subjected to laser treatment with MWCNTs coatings"
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Mechanical properties of single V2O5 nanocrystal - nanoindentation measurement in control of the max-depth
Open Research DataThe DataSet contains the nanoindentation curves (indentation force Fn vs penetrationPd) for a single V2O5 nanocrystal supported on a substrate. The measurements were performed in control of the maximum depth of Berkovich indenter penetration: 60, 70, and 100 nm.
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Investigation of the 0.4C-35Cr-45Ni-Nb Alloy after Service in High-Temperature Steam and Hydrocarbons Environment
PublicationThe paper presents the results of investigation of the 0.4C-35Cr-45Ni-Nb alloy, which operated in the cracked hydrocarbon feeds and dilution steam at 1125 C. The material originated from the pyrolytic furnace coil tubes, of which internal walls were in contact with the aforementioned medium, whereas the external walls were in contact with the flue gases. The examination included metallographic and mechanical tests on the material...
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Postquarter-Point Case of Ship’s Side-Berthing and Its Influence on Marine Fender Pitch
PublicationThis paper presents a critical analysis of some selected codes and practical recommendations used as basic rules in the design procedures of modern marine fender systems. The first part of the discussion pertains to the existing equations used in calculating the eccentricity coefficient in the ship’s kinetic energy equation and the maximum allowable fender pitch (spacing) in a set of fenders installed along a quay wall. A new approach...
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Impedance evaluation of coatings from biobased material
PublicationThe authors propose a modification of sodium caseinate edible coating for foodstuff protection. The aim was to improve the film’s barrier properties. It was achieved by the addition of propolis, which is a natural, environmentally friendly product known from its intrinsic sealing action. In the next step, propolis-admixed sodium caseinate films were exposed to elevated temperature for 10 min. This approach was meant to improve...
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Allergic Reactions as a Defense of the Organism to the Influence of Implants Components Made of Stainless Steel
PublicationDue to the increasing number of cases of hypersensitivity caused by direct contact with metals, as well as the increasing demand for implants in humans all ages numerous studies on the effects of the impact of implant components are being carried out. The paper presents the phenomenon of etiology of allergy in general terms and in relation to the biomaterials used in medicine. There have been characterized in terms of impact on...
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Allergic reactions as a defense of the organism to the influence of implants components made of stainless steel
PublicationDue to the increasing number of cases of hypersensitivity caused by direct contact with metals, as well as the increasing demand for implants in humans all ages numerous studies on the effects of the impact of implant components are being carried out. The paper presents the phenomenon of etiology of allergy in general terms and in relation to the biomaterials used in medicine. There have been characterized in terms of impact on...
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The Impact Of The Selected Parameters Of Fdm Manufacturing Technology On Tribological Performance Of Abs–Steel Pair Under Dry Friction
PublicationThe paper presents the result of tribological test of ABS and steel samples sliding under dry friction. Polymeric samples were manufactured of ABS material using FDM technology. Testing was carried out in unidirectional sliding in a ring-on-flat contact in a PT-3 tribometer. The scope of tested parameters included volumetric and mass wear, the friction coefficient, and polymeric specimen temperature. Polymeric specimens used in...
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Assessing Acute Toxicity and Endocrine Disruption Potential of Selected Packages Internal Layers Extracts
PublicationThe focus of the present study is migration of toxic substances from food contact materials and its actual influence on the health of the final consumer. Two food packagings (metal cans, TetraPack®) and five simulants medias (water, ethanol, acetic acid, DMSO, artificial saliva) were selected for simulation studies. For assessment of acute toxicity and endocrine disruption potential of extract samples, two biotests (Microtox® and...
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Computational Fluid Dynamic study on the wind characteristics of a multifunctional building system model in developed coastal cities
PublicationThis paper presents an approach for providing innovative technology by applying fluid mechanics to the field of architectural design. The aim is to make a building’s shape profitable and strengthen environmental protection by using the wind force to create an integrated wind absorption definition for a multifunctional building system model. Furthermore, taking control of the wind flow over an object can have an impact on not only...
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Crack Mouth Opening Displacement for EH36 Shipbuilding Steel Measurements Dataset
PublicationThe dataset titled EH36 steel for shipbuilding (plate thickness 50 mm) – CMOD – force record, a0/W=0.6 contains a CMOD (Crack Mouth Opening Displacement) – Force record which is the base for evaluation of the fracture toughness of structural steel. Bend specimens with a Bx2B section (B = 50 mm), and relative initial crack length a0/W=0.60 were used. The test was carried out at ambient temperature in accordance with the ISO 12135...
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Mechanical durability and electroanalytical performance of 3D-printed multi-material sensors
Open Research DataThe data set consists tensile strength, electric resistance, electrochemical characteristics and physicochemical studies of multi-material 3D printed systems, including their sensing performance during detection of antibiotics in an industrial sewage. Additionally, contact angle measurements and SEM micrographs of the electrode surfaces were included.
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Parabolic Equations with Functional Dependence
PublicationWe consider the Cauchy problem for nonlinear parabolic equations with functional dependence and prove theorems on the existence of solutions to parabolic differential-functional equations.
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Magnetosonic Excitation of the Entropy Perturbations in a Plasma with Thermal Conduction Depending on Temperature
PublicationNonlinear excitation of the entropy perturbations by magnetosonic waves in a uniform and infinite plasma model is considered. The wave vector of slow or fast mode forms an arbitrary angle (0 B B ) with the equilibrium straight magnetic field, and all perturbations are functions of the time and longitudinal coordinate. Thermal conduction is the only factor which destroys isentropicity of wave perturbations and causes the nonlinear...
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Determination of time delay between ventricles contraction using impedance measurements
PublicationThe paper presents a novel approach to assessment of ventricular dyssynchrony basing on multichannel electrical impedance measurements. Using a proper placement of electrodes, the sensitivity approach allows estimating time difference between chambers contraction from over determined nonlinear system of equations. The theoretical considerations which include Finite Element Method simulations were verified using measurements on...
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Parametric analysis of Istanbul's Ring Road viaduct for three levels of seismic load
PublicationThe paper presents a numerical analysis of the Istanbul's ring road viaduct that is currently under construction within the Northern Marmara Highway project. The structure, due to its location on seismic prone areas is exposed to seismic loads of different magnitude and different return periods. The study is fo-cused on concrete bridge supports that are design to work in nonlinear range. The study, conducted in SOFISTIK environment,...
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Contr-rotating eccentric-mass rotors used as exciters of sinusoidal forces applied to elastically supported bodies
PublicationThe work focuses on aspects of multibody dynamics. Investigated object is a mass driven by rotations of an inertial shaker. Resulting vibrational set consists of two counter-rotating identically-unbalanced rotors. Since the mass centres of the rotors do not coincide with the axes of their rotations, significant centrifugal forces arise during rotations. As both rotors are identically unbalanced, the inter-axial force components...
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Pile Model Tests Using Strain Gauge Technology
PublicationOrdinary pile bearing capacity tests are usually carried out to determine the relationship between load and displacement of pile head. The measurement system required in such tests consists of force transducer and three or four displacement gauges. The whole system is installed at the pile head above the ground level. This approach, however, does not give us complete information about the pile-soil interaction. We can only determine...
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Results of wettability evaluation of acrylic bone cements incorporating various components
Open Research DataThe database contains the images of the contact angle measurements of modified bone cements using the optical tensiometer. The following modifications were evaluated: the addition of biodegradable components (including chitosan, cellulose, tricalcium phosphate, polydioxanone or magnesium), the addition of bioactive components (bioglasses) or the addition...
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Acoustic heating produced in resonators filled by a newtonian fluid
PublicationAcoustic heating in resonators is studied. The governing equation of acoustic heating is derived by means of the special linear combination of conservation equations in differential form, allowing the reduction of all acoustic terms in the linear part of the final equation, but preserving terms belonging to the thermal mode responsible for heating. This equation is instantaneous and includes nonlinear acoustic terms that form a...
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TOXICOLOGICAL ASSESSMENT OF FOOD PACKAGES EXTRACTS
PublicationIn the scientific literature related to the widely understood issue of packaging materials designed to have contact with food (Food Contact Materials – FCM) there is much information on raw materials used for their production, their physiochemical properties, types and parameters. There is also a great number of publications on the management and disposal of used packaging. Unfortunately, not much attention is given to the matters...
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Surface and Corrosion Properties of AA6063-T5 Aluminium Alloy in Molybdate-containing Sodium Chloride Solutions
PublicationCorrosion properties of aluminium alloy AA6063-T5 were investigated in molybdate-containing NaCl solutions. Electrochemical, microscopic, and spectroscopic experiments were utilized to examine the mechanism of corrosion inhibition by molybdates. SEM-EDX, magnetic force, and intermodulation electrostatic force microscopy data suggested that the inhibition initiation preferentially occurred over Fe-rich cathodic IMPs. Spectroscopic...
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Noise and Electro-Ultrasonic Spectroscopy of Conducting PolymerThick Films
PublicationThick conducting films based on conducting polymer are characterized by DC conductivity and noise in temperature range 10 to 300 K. Conducting polymers could be used e.g. for the top electrode (cathode) in the solid tantalum or niobium capacitors. On the conducting polymer layer the top layer of carbon/graphite and/or silver polymer based pastes is applied in the capacitor technology. Our samples structure consists of conducting...
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Modelling of joining route segments of differential curvature
PublicationThe paper presents a new general method of modelling route segments curvature using differential equations. The method enables joining of route segments of different curvature. Transitional curves of linear and nonlinear curvatures have been identified in the case of joining two circular arcs by S-shaped and C-oval transitions. The obtained S-shaped curves have been compared to the cubic C-Bezier curves and to the Pythagorean hodograph...
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Analysis of Measurement Errors in Rail Vehicles’ Pantograph Inspection System
PublicationThe paper presents an approach to evaluation of height measurement errors in laser scanning inspection system. The system, consisting of a laser line generator and a specialized camera, is dedicated to diagnosing carbon contact strips of railway vehicles’ pantographs. While height measurement resolution is easily computable based on system parameters, determining the measurement error is troublesome due to numerous impacts. As...
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The morphology of as-quenched and heat treated 58(2Bi2O3-V2O5)-42SrB4O7 glasses measured with AFM
Open Research DataThe morphology of as-quenched and heat treated 58(2Bi2O3-V2O5)-42SrB4O7 glasses was measured with the use of atomic force microscope.
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Analiza drgań przewodów jezdnych sieci trakcyjnej w aspekcie oceny jej stanu technicznego
PublicationW pracy przedstawiono możliwości wykorzystania analizy drgań przewodów jezdnych sieci trakcyjnej do oceny jej stanu technicznego. Zaprezentowano wyniki badań laboratoryjnych, w których rejestrowano drgania odcinka przewodu jezdnego o zróżnicowanym stopniu zużycia i przy różnych warunkach jego zawieszenia. Na bazie przeprowadzonych analiz w dziedzinie czasu i częstotliwości, wskazano zależności między stanem sieci a wybranymi parametrami...
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Performance of organic coatings upon cyclic mechanical load
PublicationA number of engineering structures fail due to the fatigue damage resulting from cyclic mechanical stress. However, as far as organic coatings are concerned this degradation factor remains underestimated. In the paper the authors propose a methodology combining global electrochemical impedance spectroscopy and local atomic force microscopy measurements for evaluation of coating resistance to an impact of repetitive mechanical stress. Typical...