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Search results for: DYNAMIC NOISE MAP
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PREDICTION OF SHIP MOTIONS IN IRREGULAR WAVES BASED ON RESPONSE AMPLITUDE OPERATORS EVALUATED EXPERIMENTALLY IN NOISE WAVES
PublicationThe most common methods for predicting ship roll motions in a specified sea state are direct measurements of motions in a representative irregular wave realisation (time domain) or calculations of motions from response amplitude operators (RAOs) in the frequency domain. The result of the first method is valid only for the tested sea state, whilst the second method is more flexible but less accurate. RAO-based predictions are calculated...
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Performance evaluation of unified memory and dynamic parallelism for selected parallel CUDA applications
PublicationThe aim of this paper is to evaluate performance of new CUDA mechanisms—unified memory and dynamic parallelism for real parallel applications compared to standard CUDA API versions. In order to gain insight into performance of these mechanisms, we decided to implement three applications with control and data flow typical of SPMD, geometric SPMD and divide-and-conquer schemes, which were then used for tests and experiments. Specifically,...
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On time-dependent nonlinear dynamic response of micro-elastic solids
PublicationA new approach to the mechanical response of micro-mechanic problems is presented using the modified couple stress theory. This model captured micro-turns due to micro-particles' rotations which could be essential for microstructural materials and/or at small scales. In a micro media based on the small rotations, sub-particles can also turn except the whole domain rotation. However, this framework is competent for a static medium....
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History-based dynamic weight voting for multi-agent systems
PublicationTaking decision in multi-agent systems may involve voting. Two basic voting protocols are surveyed in the paper. Then, a new history-based dynamic weight voting is proposed. This voting protocol allows for identification of the agents which contribute to the correct system decision. The proposed solution is contrasted with majority voting and with weighted average voting, to show its advantages
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A new approach to active noise and vibration control - [Part I: the known frequency case]
PublicationThis paper presents a new approach to rejection of complex-valued sinusoidal disturbances acting at the output of a discrete-time stable linear plant with unknown dynamics. It is assumed that the frequency of the sinusoidal disturbance is known, and that the output signal is contaminated with wideband measurement noise. The disturbance rejection control rule is first derived and analyzed for a nominal plant model, different from...
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Comparison of noise reduction methods in radiometric correlation measurements of two-phase liquid-gas flows
PublicationTwo-phase liquid-gas flows occur frequently in the mining, energy, chemical, and petrochemical industries. One of non-contact methods used to analyse these flows is the gamma ray absorption method. However, the signals received from radiation detectors contain a significant stochastic noise, which makes them difficult to analyse. The article describes four methods of noise reduction in cross-correlation measurements of water-air...
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Identification of diagnostic parameter sensitivity during dynamic processes of a marine engine
PublicationChanging some parameters of the engine structure alters the emission of harmful components in the exhaust gas. This applies in particular to the damage of charge exchange system as well as fuel system and engine supercharger. These changes are much greater during the dynamic states and their accompanying transitional processes. The different sensitivity of diagnostic parameters to the same force, coming from the engine structure, but...
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Fading Modelling in Dynamic Off-Body Channels
PublicationThis paper presents an off-body fading channel model for Body Area Networks (BANs) in indoor environments. The proposed model, which is based on both simulations and measurements in a realistic environment, consists of three components: mean path loss, body shadowing, and multipath fading. Seven scenarios in an indoor environment (a medium-size room with furniture, mostly consisting of wooden tables and chairs) have been measured:...
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Simulation model for evaluation of QOS dynamic routing
PublicationCurrent informational networks use a large variety of technologies to support data exchange. Most of them are focused on IP protocol and include mechanisms which by definition should supply demanded QoS. One of those mechanisms is efficient path calculation - routing. Traffic offered to the network can change very rapidly in short term. Routing should support such traffic changes and all the time calculate valid paths in terms...
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Control System Design for Dynamic Positioning using Vectorial Backstepping
PublicationThe problem of synthesis a dynamic positioning system for low frequency model of surface vessel was considered in this paper. The recursive vectorial backstepping control design was used to keep a fixed position and heading in presence of wave disturbances. The passive observer was introduced to smooth the measurements and to estimate the velocities needed for the control algorithm. The computer simulation results were given to...
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The consequences of dynamic BPM
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universal system for diagnosing environmental noise.
PublicationW publikacji przedstawiono projekt multimedialnego systemu komputerowego do monitoringu hałasu środowiskowego. Opracowywany system jest powiązany z aktualnie realizowanym w Katedrze Inżynierii Dźwięku i Obrazu Politechniki Gdańskiej projektem, którego celem jest redukcja częstości występowania niedosłuchu. Niedosłuch często jest wywołany przez nadmierny hałas przemysłowy, komunikacyjny lub innego rodzaju niepożądane dźwięki, towarzyszące...
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RTS Noise in Optoelectronic Coupled Devices
PublicationPrzedstawiono wyniki pomiarów szumów z zakresu małuch częstotliwości transoptorów typu CNY17. Pomiary wykonano w systemie zaprojektowanym i skonstruowanym przez Autorów. Stwierdzono występowanie szumów RTS w kilku egzemplarzach badanej próby transoptorów. Przeprowadzono analizę szumów RTS, zarówno w dziedzinie czasu, jak i w dziedzinie częstotliwości. Oszacowano wartość częstotliwości, przy której występują szumy wybuchowe, na...
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The stationarity characteristics of electrochemical current noise
PublicationPrzedstawiono rezultaty analizy szumu elektrochemicznego generowanego podczas korozji stali 0H18N9 w roztworze 0.1 M H2SO4+0,006 M Cl-. Rejestry uzyskano w warunkach potencjostatycznych. W szumie zaobserwowano trendy i sygnały przejściowe, charakterystyczne dla korozji wżerowej. Trend został usunięty za pomocą aproksymacji wielomianem trzeciego stopnia. Analiza statystyczna wykazała niestacjonarny bądź słabo stacjonarny charakter...
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Tyre/road noise. Reference book.
PublicationKsiążka przedstawia zagadnienia związane z hałasem opon samochodowych poruszających się po nawierzchniach drogowych. Zawiera rozdziały poświęcone budowie opon, budowie nawierzchni drogowych, akustyce, mechanizmom generowania hałasu, wpływie czynników eksploatacyjnych i konstrukcyjnych na hałas opon, metodom pomiarowym, modelowaniu, metodom ograniczania hałasu opon, zagadnieniom prawnym i normalizacyjnym. Jest kompletnym przewodnikiem...
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Novel applications of noise in sensing and communications
PublicationPrzedstawiono zaproponowane w ostatnich latach sposoby wykorzystania szumów do wykrywania gazów, jako źródła informacji o atmosferze otaczającej czujnik. Ponadto, przedstawiono możliwości wykorzystania zjawisk losowych do bezpiecznej komunikacji.
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The Low-frequency Noise of SiC MESFETs
PublicationPrzedstawiono system do pomiaru szumów małoczestotliwościowych tranzystorów SiC MESFET oraz przykładowe wyniki pomiarów.
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Numerical and experimental propeller noise investigations
PublicationThe standard propeller has been investigated in model scale, using medium size cavitation tunnel. The hydroacoustic characteristics of propellers under different loading conditions have been investigated. Additionally the presented experimental results have been used for the verification of applied numerical approach. During both numerical and experimental analyses non-uniform inflow propeller’s conditions have been adapted. Good...
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Dynamic Analysis of the Turnout Diverging Track for HSR with Variable Curvature Sections
PublicationThe paper presents an analytical method of identifying the curvature of the turnout diverging track consisting of sections of varying curvature. Both linear and nonlinear (polynomial) curvatures of the turnout diverging track are identified and evaluated in the paper. The presented method is a universal one, it enables to assume curvature values at the beginning and end point of the geometrical layout of the turnout. The results...
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Development of dynamic method for evaluation of inhibition efficiency on the example of 8-hydroxyquinolin
PublicationSelection of a proper inhibitor should be based on the evaluation of its mechanism and effective concentrations. Mechanism of inhibition usually has dynamic character due to changing physicochemical conditions of the environment and corroding metal surface. Most of actually used methods are stationary or contain assumptions which highly influences obtained values. Development of new dynamic method, based on modified EIS, allows...
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Composite sandwich footbridge - measured dynamic response vs. FEA
PublicationThe paper describes a process of in situ dynamic tests of a composite sandwich footbridge before its accepta-tion for exploitation in real traffic conditions. It is only a part of a big research task that includes design, manufacture and introduce practical application of the bridge. The in situ measured natural modes and fre-quencies are compared with numerically determined ones. Finite element analysis is established to estimate...
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Fixed Pattern Noise Reduction and Linearity Improvement in Time-Mode CMOS Image Sensors
PublicationIn the paper, a digital clock stopping technique for gain and offset correction in time-mode analog-to-digital converters (ADCs) has been proposed. The technique is dedicated to imagers with massively parallel image acquisition working in the time mode where compensation of dark signal non-uniformity (DSNU) as well as photo-response non-uniformity (PRNU) is critical. Fixed pattern noise (FPN) reduction has been experimentally validated...
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SPECTRAL DYNAMIC ANALYSIS OF A STATIONARY JACK-UP PLATFORM
PublicationThe paper refers to the dynamic short-term response analysis of the Baltic steel drilling platform (see Fig.2) in a random sea-state represented by one-dimensional wave spectrum proposed by Striekalov and Massel and it is recommended for the Baltic Sea area. The Baltic drilling platform is a jack-up type platform for the exploration and exploitation of oil under the Baltic Sea. The analysis presented deals with the stationary...
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Quantitative Active Dynamic Thermal IR-Imaging and Thermal Tomography in Medical Diagnostic
PublicationPrinciples of Active dynamic thermal (ADT) IR-imaging and Thermal Tomography are described in details. Basic medical applications of this new modality are also discussed.
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Ultra-Wideband Vivaldi Antenna with an Integrated Noise-Rejecting Parasitic Notch Filter for Online Partial Discharge Detection
PublicationPower transformers and gas-insulated switchgear (GIS) play crucial roles in electrical power grids. However, they may suffer from degradation of insulation material due to wear and tear, leading to their imminent failure. Partial discharges (PDs) are an initial sign of insulation materials degradation which emit signals spanning various physical domains, including electromagnetic. PDs are temporally narrow, high-frequency, stochastic...
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Comparison of pavement noise properties on selected road sections using different CPX measuring systems: self-powered vehicle and special test trailer
PublicationThe recently published ISO standard intended to measure the noise properties of road surfaces in a standardized method (ISO 11819-2:2017) precisely defines measurement procedure of the influence of road surface on traffic noise. According to it, two types of test vehicles may be utilized: a self-powered vehicle fitted with one or more test tyres and a trailer towed by a separate vehicle with one or more test tyres mounted on the...
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Validation of dynamic electrochemical impedance spectrograms using autocorrelation function
PublicationValidation of impedance data is essential for checking the reliability of experimental data. Kramers – Kronig transformation is used to verify data obtained from classical Electrochemical Impedance Spectroscopy (EIS) measurements. Data obtained from Dynamic Electrochemical Impedance Spectroscopy (DEIS) could be validated in the same way, but in this case, there is no information about internal consistency between every single spectrum...
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Electrochemical Evaluation of Sustainable Corrosion Inhibitors via Dynamic Electrochemical Impedance Spectroscopy
PublicationFinding suitable measurement methods for the effective management of electrochemical problems is of paramount importance, particularly for improving efficiency in corrosion protection. The need for accurate measurement techniques specific to nonstationary conditions has long been recognized, and promising approaches have emerged. This chapter introduces dynamic electrochemical impedance spectroscopy as a novel advancement in electrochemistry...
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Experimental determination of dynamic properties of cylindrical steel tank model filled with liquid
PublicationIn technical branches, such as chemical or petroleum industries, cylindrical steel tanks are essential structures used for storage of liquid products. Any failure might have disastrous consequences, therefore their safety and reliability is essential. The aim of the present paper is to show the results of the experimental study which has been conducted on a scaled model of a real tank used in Poland. The investigation was carried...
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High-Precision FIR-Model-Based Dynamic Weighing System
PublicationConveyor belt-type checkweighers are increasingly popular components of modern production lines. They are used to assess the weight of the produced items in motion, i.e., without stopping them on the weighing platform. The main challenge one faces when designing a dynamic weighing system is providing high measurement accuracy, especially at high conveyor belt speeds. The approach proposed in this paper can be characterized as a...
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Self-Organising map neural network in the analysis of electromyography data of muscles acting at temporomandibular joint.
PublicationThe temporomandibular joint (TMJ) is the joint that via muscle action and jaw motion allows for necessary physiological performances such as mastication. Whereas mandible translates and rotates [1]. Estimation of activity of muscles acting at the TMJ provides a knowledge of activation pattern solely of a specific patient that an electromyography (EMG) examination was carried out [2]. In this work, a Self-Organising Maps (SOMs)...
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Creation of a map of optimal spindle speeds for a purpose of surveillance of high speed milling of flexible details
PublicationDrgania samowzbudne typu chatter często towarzyszą procesom frezowania szybkościowego. Ich skutkiem są nieodwracalne uszkodzenia powierzchni obrabianej. Mogą one również doprowadzić do intensywnego zużycia narzędzi skrawających, a nawet samej obrabiarki. W pracy przedstawiono metodę umożliwiającą tworzenie mapy optymalnych prędkości obrotowych wrzeciona. Stosowanie podczas procesu frezowania optymalnej prędkości obrotowej wrzeciona...
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General form of fixed point indices of an iterated C^1 map andinfiniteness of minimal periods
PublicationDla zwartego podzbioru punktów periodycznych gładkiego odwzorowania podana zostaje formuła na indeksy iteracji. Wynik stanowi uogólnienie rezultatu Chowa, Malleta-Pareta i Yorke'a.
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The Optimal Spindle Speed Map for Reduction of Chatter Vibration During Milling of Bow Thruster Blade
PublicationW artykule przedstwiono przykład wykorzystania procedury tworzenia mapy optymalnych prędkosci obrotowych w celu ograniczenia drgań samowzbudnych podczas frezowania płata śruby okrętowego steru strumieniowego.
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Effect of starch fillers on the dynamic mechanical properties of rubber biocomposite materials
PublicationIn the paper the results of dynamic mechanical study of the biocomposites containing one of two types of (potato or corn) strach used as fillers in different amount were discussed. The composites were obtained from rubbery mixture containing natural rubber (NR) as a main component. Thermomechanical analyses (by DMA) showed that the used quantity of strach fillers only slightly influence on the glass transition temperature of vulcanizates.
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Simulation Results of Dynamic Capacity Reallocation in Hierarchical Cell Structure of UMTS Network
PublicationIn the paper simulation results of dynamic capacity reallocation between different layers of hierarchical cell structure of UMTS network has been described. This approach for load management seems to be useful for improving the resource utilization perfmorance.
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Modified dynamic time warping method applied to handwritten signature authenticity verification
PublicationA signature verification system based on static features and time-domain functions of signals obtained using a tablet has been presented in the paper. The signature verification method, based mainly on dynamic time warping coupled with some signature image features, has been described. The FRR measures reflecting the method’s efficiency have been evaluated for verification attempts performed directly after obtaining model signatures...
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DYNAMIC POSITIONING CAPABILITY ASSESSMENT BASED ON OPTIMAL THRUST ALLOCATION
PublicationThe article presents an efficient method of optimal thrust allocation over the actuators in a dynamically positioned ship, according to the DNV-ST-0111 standard, Level 1. The optimisation task is approximated to a convex problem with linear constraints and mathematically formulated as quadratic programming. The case study is being used to illustrate the use of the proposed approach in assessing the DP capability of a rescue ship....
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Generating optimal paths in dynamic environments using RiverFormation Dynamics algorithm
PublicationThe paper presents a comparison of four optimisation algorithms implemented for the purpose of finding the shortest path in static and dynamic environments with obstacles. Two classical graph algorithms –the Dijkstra complete algorithm and A* heuristic algorithm – were compared with metaheuristic River Formation Dynamics swarm algorithm and its newly introduced modified version. Moreover, another swarm algorithm has been compared...
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Static and dynamic modelling blow- out type trauma of orbital wall
PublicationAuthors of the paper present initial results of finite element analysis of a blow-out type trauma of orbital wall. The research is liked with laboratory tests for the Young’s modulus of bones evaluation. In the finite element analysis the neighbourhood of orbital wall is modelled by triangle thin shell finite elements. In the paper results of nonlinear static and transient dynamic analysis (including damping) are compared. The...
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Determination of magnetisation conditions in a Double-Core Barkhausen Noise measurement set-up
PublicationThe magnetic Barkhausen effect is useful forassessing 1D and 2D stress states of ferromagnetic steelobjects. However, its extension to technically importantmaterials, such as duplex anisotropic steels, remains challenging. The determination of magnetisation inside the studied object and the electromagnet for various geometries, materials and magnetisation angles is a key issue.Three-dimensional, dynamic finite element analysis...
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Analysis of data fusion algorithms for the vessel with the dynamic positioning system
PublicationThe dynamic positioning (DP) system on the vessel is operated to control the position and heading of the vessel with the use of propellers and thrusters installed on the board. On DP vessels redundant measurement systems of position, heading and the magnitude and direction of environmental forces are required for safety at sea. In this case, a fusion of data is needed from individual measurement devices. The article proposes a...
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Export diversification and economic development: a dynamic spatial data analysis
PublicationThis paper contributes to the empirical literature on the relationship between ‘export variety’ (export diversification) and economic development by relaxing the assumption of cross-country independence and allowing for spatial diffusion of shocks in observed and unobserved factors. Export variety is measured for a balanced panel of 114 countries (1992-2012) using very detailed information on their exports (HS 6-digit product...
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Dynamic characteristics of the proton exchange membrane fuel cell module
PublicationThe paper describes a fuel cell based system and its performance. The system is based on two fuel cell units, DC/DC converter, DC/AC inverter, microprocessor control unit, load unit, bottled hydrogen supply system and a set of measurement instruments. In the study presented in the paper a dynamic response of the proton exchange membrane (PEM) fuel cell system to unit step change load as well as to periodical load changing cycles...
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Elimination of impulsive disturbances from archive audio files – comparison of three noise pulse detection schemes
PublicationThe problem of elimination of impulsive disturbances (such as clicks, pops, ticks, crackles, and record scratches) from archive audio recordings is considered and solved using autoregressive modeling. Three classical noise pulse detection schemes are examined and compared: the approach based on open-loop multi-step-ahead signal prediction, the approach based on decision-feedback signal prediction, and the double threshold approach,...
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The current amplifier in low frequency noise measurements; Absolute calibration and rigorous 1/f noise extraction for MOSFET´s
PublicationPrzedstawiono budowę wzmacniacza prądowego i sposób obliczania szumów wyjściowych przy dołączonym do wejścia rezystorze wzorcowym. Przedstawiono wyniki eksperymentów potwierdzających prawidłowość przyjętego sposobu postępowania. Zaproponowano metodę wyznaczania składowej 1/f szumów drenu tranzystora MOSFET.
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Polynomial description of dynamic impedance spectrogram—introduction to a new impedance analysis method
PublicationThis paper presents a polynomial description of spectrograms obtained using Dynamic Electrochemical Impedance Spectroscopy. A method to fit the polynomial degree correctly is discussed. A simple electrical system of a diode connected in parallel with a capacitor was used for testing. Dynamic impedance measurements during potentiodynamic polarization were conducted. This paper presents an alternative analysis method that allows...
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Neural modelling of dynamic systems with time delays based on an adjusted NEAT algorithm
PublicationA problem related to the development of an algorithm designed to find an architecture of artificial neural network used for black-box modelling of dynamic systems with time delays has been addressed in this paper. The proposed algorithm is based on a well-known NeuroEvolution of Augmenting Topologies (NEAT) algorithm. The NEAT algorithm has been adjusted by allowing additional connections within an artificial neural network and...
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Dynamic Nanoimpedance Characterization of the Atomic Force Microscope Tip-Surface Contact
PublicationNanoimpedance measurements, using the dynamic impedance spectroscopy technique, were carried out during loading and unloading force of a probe on three kinds of materials of different resistivity. These materials were: gold, boron-doped diamond, and AISI 304 stainless steel. Changes of impedance spectra versus applied force were registered and differences in the tip-to-sample contact character on each material were revealed. To...
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Analysis of electrochemical noise by means of bispectral technique
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