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Search results for: single-sided lapping
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Bounds on the Cover Time of Parallel Rotor Walks
PublicationThe rotor-router mechanism was introduced as a deterministic alternative to the random walk in undirected graphs. In this model, a set of k identical walkers is deployed in parallel, starting from a chosen subset of nodes, and moving around the graph in synchronous steps. During the process, each node maintains a cyclic ordering of its outgoing arcs, and successively propagates walkers which visit it along its outgoing arcs in...
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Linear game non-contextuality and Bell inequalities—a graph-theoretic approach
PublicationWe study the classical and quantum values of a class of one-and two-party unique games, that generalizes the well-known XOR games to the case of non-binary outcomes. In the bipartite case the generalized XOR(XOR-d) games we study are a subclass of the well-known linear games. We introduce a 'constraint graph' associated to such a game, with the constraints defining the game represented by an edge-coloring of the graph. We use the...
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Exploring the Beam Squint Effects on Reflectarray Perfromance: A Comprehensive Analysis of the Specular and Scattered Reflection of the Unit Cell
PublicationIn this article, the phenomena of beam deviation in reflectarray is discussed. The radiation pattern of the unit cell, which plays a vital role in shaping the beam of the reflectarray, is analyzed by considering undesired specular and scattered reflections. These unwanted reflections adversely affect the pattern of the single unit cell, thereby reducing the overall performance of the reflectarray. To conduct our investigations,...
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Conditions for increasing the recognition of degradation in thermal-flow diagnostics, taking into account environmental legal aspects
PublicationThe ever-increasing demand for electricity and the need for conventional sources to cooperate with renewable ones generates the need to increase the efficiency and safety of the generation sources. Therefore, it is necessary to find a way to operate existing facilities more efficiently with full detection of emerging faults. These are the requirements of Polish, European and International law, which demands that energy facilities...
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Zastosowanie metod eksploracji danych do analizy odpowiedzi czujników gazu
PublicationZagadnienia poruszane w niniejszej rozprawie dotyczą zastosowania metod eksploracji danych do analizy odpowiedzi czujników gazu, umożliwiających poprawną identyfikację składu mieszaniny gazowej w elektronicznych systemach rozpoznawania gazu. Elektroniczne systemy rozpoznawania gazu to urządzenia wykorzystujące czujniki gazu oraz odpowiednio dobrane metody analizy danych pomiarowych, zdolne do określenia składu mierzonej mieszaniny...
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Using multibeam echoes in seafloor characterisation and classification
PublicationThe method of seabed identification and classification from multibeam sonar echoes is presented. The proposed approach is based on calculation of a set of parameters of an echo envelope, similarly as in seafloor classification using single beam echosounder. These parameters are extracted for each consecutive beam allowing the estimation of their dependence on the seafloor incident angle. The relation between seabed type and calculated...
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Comparison of sound of organ pipes in contemporary and historical instruments
PublicationThe aim of this research is to examine the differences in the timbre of organ pipes’ sound between a historical and a contemporary organ instrument. The historical instrument is the Oliwa organ from Gdansk, Poland, and the contemporary one is from Kartuzy, Poland. Recordings are made of single notes played by an open labial pipe that belongs to the Principal rank. The analyses and comparison of several sound features compatible...
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3D POINT-CLOUD SPATIAL EXPANSION BY TOTAL LEAST-SQUARES LINE FITTING
PublicationPoint-cloud spatial expansion (PCSE) allows the creation of a new pointcloud form that presents an alternative geometry of an entire object in a single spatial view. Spatial expansion facilitates the analysis process and introduces an additional spatial parameter describing the point cloud. An important element of the PCSE method is determining the position of the axis of symmetry of a symmetrical object: the procedure for determining...
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Mathematical Approach to Assess a Human Gait
PublicationA purpose of the paper was to create a mathematical approach to assess a human gait. The scope of the study was to model a normal gait in the sagittal plane and frontal plane of the body. Applying the Newton-Euler formulation, three multibody biomechanical models were derived to describe single support phase and double support phase of the gait. To model a gait in the sagittal plane the open-close sagittal 6DOF model and the open-close...
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Crystal growth and properties of a binary intermetallic ZrBi2 compound
PublicationSingle crystals of ZrBi2 were grown by a self-flux method. The material adopts TiAs2 structure type with lattice parameters: a = 10.233(4) Å, b = 15.581(2) Å, c = 3.994(5) Å. Crystals of ZrBi2 were studied by means of magnetic susceptiblity, specific heat and resistivity measurements. The compound reveals a metallic-like behavior (RRR = 30). The Sommerfeld coefficient equals γ = 1.59(16) mJ mol-1 K-2 and Debye temperature ΘD =...
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Dual-wavelength laser polarimeter and its performance capabilities
PublicationA dual-wavelength optical polarimetric approach has been proposed as a means of elimination of the systematic errors and estimation of the optical anisotropy parameters for a single DKDP crystal. Our HAUP-related polarimeter uses two semiconductor lasers with the neighbouring wavelengths of 635 nm and 650 nm. Based on the temperature dependence analysis of small characteristic azimuths of light polarization with respect to the...
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A Compact and Lightweight Microwave Tilt Sensor Based on an SRR-Loaded Microstrip Line
PublicationIn this paper, the symmetry property of split ring resonators (SRRs) is exploited to develop a tilt sensor. The sensor is composed of an SRR-loaded microstrip line operating at microwave frequencies. It is shown that the depth of notch in the reflection characteristic of the microstrip is a function of the tilt angle of the SRR. Thus, it can be used for sensing inclination. The sensor benefits from very compact size and light weight....
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KTaO3-based nanocomposites for air treatment
PublicationA series of single semiconductors and their nanocomposites combination (such as KTaO3 + CdSe + SrTiO3; KTaO3 + CdS +WO3; KTaO3 + CdS + MoS2) were prepared using hydrothermal route. Photocatalytic activity of as-prepared nanocomposites was estimated by photocatalytic degradation of toluene in the gas phase using light-emitting diodes (LEDs, 375 nm) in four subsequent cycles. The nanocomposites were characterized by scanning electron...
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General route for the synthesis of terminal phosphanylphosphido complexes of Zr(IV) and Hf(IV): Structural investigations of the first zirconium complex with a phosphanylphosphido ligand
PublicationReactions of R2P-P(SiMe3)Li with [Cp2MCl2] (M = Zr, Hf) in hydrocarbons yield the related terminal phosphanylphosphidocomplexes [Cp2M(Cl){(Me3Si)P-PR2-jP1}] (R = iPr and tBu). The solid state structures of [Cp2M(Cl){P(SiMe3)-PiPr2-jP1}] (M = Zr, Hf) were established by single crystal X-ray diffraction studies. The phosphido-P atoms adopt almost planar geometries and the phosphanyl P atoms adopt pyramidal geometries. The reaction...
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Experimentation, material modelling and simulation of bonded joints with a flexible adhesive
PublicationThe paper deals with material parameters identification of a flexible adhesive and the numerical simulation of its behaviour in a single lap bonded joint. The material modelling was based on the simple shear and tensile-shear laboratory tests of the bonded joints made of thin aluminium and polyurethane plates with the flexible adhesive Terostat MS 9360 manufactured by Henkel AG & Co. The adhesive was considered as a hyperelastic...
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Modeling and Simulation for Exploring Power/Time Trade-off of Parallel Deep Neural Network Training
PublicationIn the paper we tackle bi-objective execution time and power consumption optimization problem concerning execution of parallel applications. We propose using a discrete-event simulation environment for exploring this power/time trade-off in the form of a Pareto front. The solution is verified by a case study based on a real deep neural network training application for automatic speech recognition. A simulation lasting over 2 hours...
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Dissociative electron attachment and anion-induced dimerization in pyruvic acid
PublicationWe report partial cross sections for the dissociative electron attachment to pyruvic acid. A rich fragmentation dynamics is observed. Electronic structure calculations facilitate the identification of complex rearrangement reactions that occur during the dissociation. Furthermore, a number of fragment anions produced at electron energies close to 0 eV are observed, that cannot originate from single electron-molecule collisions....
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Thermo-elastic non-linear analysis of multilayered plates and shells
PublicationGeometrically nonlinear FEM analysis of multilayered composite plates and shells is performed in order to resolve the stability problem of the structures being under the influence of temperature field. The Riks-Wempner-Ramm algorithm with a specially modified multi-choice unloading condition has been implemented in authors’ numerical code. As the representation of multilayered medium the Equivalent Single Layer approach with the...
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Discussion of “Development of an Accurate Time integration Technique for the Assessment of Q-Based versus h-Based Formulations of the Diffusion Wave Equation for Flow Routing” by K. Hasanvand, M.R. Hashemi and M.J. Abedini
PublicationThe discusser read the original with great interest. It seems, however, that some aspects of the original paper need additional comments. The authors of the original paper discuss the accuracy of a numerical solution of the diffusion wave equation formulated with respect to different state variables. The analysis focuses on nonlinear equations in the form of a single transport equation with the discharge Q (volumetric flow rate)...
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Dipole-driven dynamics for near-threshold electron/positron interactions with pyrimidinic DNA bases: a path to compound formations
PublicationCalculations are reported for electron and positron scattering from isolated cytosine and thymine, where the two pyrimidinic single-ring DNA bases, in the gas-phase at energies near the elastic threshold, they reveal the special features of the dipole-driven scattering states. All molecules examined exhibit, in fact, supercritical (>1.67 D) permanent dipoles which can therefore also support, below threshold, excited bound compound...
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Modelling of Objects Behaviour for Their Re-identification in Multi-camera Surveillance System Employing Particle Filters and Flow Graphs
PublicationAn extension of the re-identification method of modeling objects behavior in muti-camera surveillance systems, related to adding a particle filter to the decision-making algorithm is covered by the paper. A variety of tracking methods related to a single FOV (Field of Vision) are known, proven to be quite different for inter-camera tracking, especially in case of non-overlapping FOVs. The re-identification methods refer to the...
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Smart heating system for home extending utilization of renewable energy sources
PublicationIn the paper a modern approach to smart home heating is presented. Proposed solution utilizes at least two low-polluting energy source technologies. The main idea is to connect well known ecological energy sources in a way that they can support each other and minimize risks of failure when using single system or even both of them but managed in separate way. Considered energy technologies, used separatelly, have disadvan-tages,...
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Fluctuation enhanced gas sensing with WO3-based nanoparticle gas sensors modulated by UV light at selected wavelengths
PublicationThe sensitivity and selectivity of WO3-based gas sensors can be enhanced by UV-irradiation-induced modulation, especially if different wavelengths are employed. We used fluctuation-enhanced gas sensing, based on measurements of resistance fluctuations in the gas sensor, to study the effects of such modulation on the noise intensity for ambient atmospheres of synthetic air without and with additions of small amounts of ethanol,...
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Sensitivity analysis of a composite footbridge
PublicationThis work include an example of sensitivity analysis for the design of a composite footbridge. A sandwich structure is used, consisting two high-strength skins separated by a core material. The analysis was conducted for two numerical models. The first one is a simple, single-span beam of a composite cross-section (laminate and foam), with different Young’s modulus for each material. Calculations were made by means of a MATLAB-based...
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Design of microstrip antenna subarrays: a simulation-driven surrogate-based approach
PublicationA methodology for computationally efficient simulation-driven design of microstrip antenna subarrays is presented. Our approach takes into account the effect of the feed (here, a corporate network) on the subarray side-lobe level and allows adjustment of both radiation and reflection responses of the structure under design within a single automated process. This process is realized as surrogate-based optimization that produces...
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Simulation-Driven Design of Microstrip Antenna Subarrays
PublicationA methodology for computationally efficient simulation-driven design of microstrip antenna subarrays is presented. Our approach takes into account the effect of the feed (e.g., a corporate network) on the subarray side lobe level and allows adjusting both radiation and reflection responses of the structure under design within a single automated process. This process is realized as surrogate-based optimization that produces designs...
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ECG-based prediction of ventricular fibrillation by means of the PCA
PublicationA Sudden Cardiac Death (SCD) is a death resulting from cardiac failure with no significant symptoms earlier than one hour before occurrence. It is the cause of for approximately 400000 deaths per year in United States and millions of deaths worldwide. The proposed system, including two-stage algorithm and wearable diagnostic device allows for SCD risk estimation and continuous monitoring of high risk patients. A single channel...
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Automated detection of sleep apnea and hypopnea events based on robust airflow envelope tracking
PublicationThe paper presents a new approach to detection of apnea/hypopnea events, in the presence of artifacts and breathing irregularities, from a single-channel airflow record. The proposed algorithm identifies segments of signal affected by a high amplitude modulation corresponding to apnea/hypopnea events. It is shown that a robust airflow envelope—free of breathing artifacts—improves effectiveness of the diagnostic process and allows...
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APIS – Agent Platform for Integration of Services
PublicationThe paper presents an approach to creating the platform for development and evaluation of complex tasks execution algorithms. Proposed solution is based on an agent paradigm where independent peers can cooperate and negotiate in order to execute specified tasks which are defined only by the final output description. Tasks are realized by the means of services exposed by different peers. In case when there is no single service fulfilling...
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On root finding algorithms for complex functions with branch cuts
PublicationA simple and versatile method is presented, which enhances the complex root finding process by eliminating branch cuts and branch points in the analyzed domain. For any complex function defined by a finite number of Riemann sheets, a pointwise product of all the surfaces can be obtained. Such single-valued function is free of discontinuity caused by branch cuts and branch points. The roots of the new function are the same as the...
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METHOD OF TRAINING THE ENDOSCOPIC VIDEO ANALYSIS ALGORITHMS TO MAXIMIZE BOTH ACCURACY AND STABILITY
PublicationIn the article a new training and testing method of endoscopic video analysis algorithms is presented. Classical methods take into account only eciency of recognizing objects on single video frames. Proposed method additionally considers stability of classiers output for real video input. The method is simple and can be trained on data sets created for other solutions. Therefore, it is easily applicable to existing endoscopic video...
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Magnetic properties of ferromagnetic Pu2Pt3Si5
PublicationThe structural, magnetic, and thermodynamic properties of a new plutonium based compound, Pu2Pt3Si5, are reported. Single crystals produced by a Sn-flux technique have been analyzed showing a ferromagnetic behavior at 58 K. Pu2Pt3Si5 crystallizes in the U2Co3Si5-type orthorhombic Iabm structure (s.g. 72) with atomic parameters a = 9.9226(2) Å, b = 11.4436(2) Å and c = 6.0148(1) Å. The effective (leff 0.74 lB/Pu) and saturated (rsat...
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Design and experimental verification of multi-layer waveguide using pin/hole structure
PublicationThis study presents a novel technique for minimizing RF leakage in metallic hollow waveguides fabricated using the multilayer split-block method. By integrating a pin/hole wall into the split-block multilayers, a substantial reduction of RF leakage can be achieved while reducing the circuit size and mitigating the performance variations. To validate the proposed approach, a slot antenna fed by single ridge waveguide has been prototyped...
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Probability distribution of flicker noise in AuNPdecorated graphene–Si Schottky barrier diode
PublicationWe present results of the probability distribution analysis of flicker noise generated in Au nanoparticle (AuNP) decorated graphene–Si Schottky barrier diodes with and without yellow light illumination (592 nm), close to the localized surface plasmon resonance in the AuNPs (586 nm). The AuNPs occupy imperfections in the single-layer graphene and reduce the flicker noise intensity generated in the graphene layer. The estimated probability...
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Exchange-Traded Funds in Europe
PublicationExchange-Traded Funds in Europe provides a single point of reference on a diverse set of regional ETF markets, illuminating the roles ETFs can play in risk mitigation and speculation. Combining empirical data with models and case studies, the authors use diffusion models and panel/country-specific regressions—as well as graphical and descriptive analyses— to show how ETFs are more than conventional, passive investments. With new...
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Heat transfer and pressure drop characteristics of the silicone-based plate heat exchanger
PublicationThe paper presents an experimental investigation of a silicone based heat exchanger, with passive heat transfer intensification by means of surface enhancement. The main objective of this paper was to experimentally investigate the performance of a heat exchanger module with the enhanced surface. Heat transfer in the test section has been examined and described with precise measurements of thermal and flow conditions. Reported...
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Bi-based halide perovskites: Stability and opportunities in the photocatalytic approach for hydrogen evolution
PublicationIn this study, we successfully prepared Bi-based single perovskites of the A3Bi2I9 type (A = Cs, Rb, MA, FA), and, for the first time, attempted to experimentally obtain double perovskites Cs2B’BiI6 type (B′ = Ag, Au, In, Cu). Despite the premises available in theoretical studies, our research has proven the impossibility of the existence of double perovskites of this type. Nevertheless, both types of obtained materials were subjected...
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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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Probe signal processing for channel estimation in underwater acoustic communication system
PublicationUnderwater acoustic communication channels are characterized by a large variety of propagation conditions. Designing a reliable communication system requires knowledge of the transmission parameters of the channel, namely multipath delay spread, Doppler spread, coherence time, and coherence bandwidth. However, the possibilities of its estimation in a realtime underwater communication system are limited, mainly due to the computational...
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Selected studies of flow maldistribution in a minichannel plate heat exchanger
PublicationAnalysis of the state of-the-art in research of minichannel heat exchangers, especially on the topic of flow maldistribution in multiple channels, has been accomplished. Studies on minichannel plate heat exchanger with 51 parallel minichannels with four hydraulic diameters, i.e., 461 μm, 574 μm, 667 μm, and 750 μm have been presented. Flow at the instance of filling the microchannel with water at low flow rates has been visualized. The...
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Miniaturized dual‐band branch‐line coupler with enhanced bandwidth
PublicationIn this letter, a miniaturized hybrid dual-band branch-line coupler (BLC) with enhanced fractional bandwidths is proposed. Compact size and bandwidth enhancement are obtained using meandered transmission line sections with broken symmetry between cross-coupling branches. The circuit is designed at a low numerical cost using surrogate-assisted techniques. The optimized design features small size of only 0.25λg×0.19λg(28% miniaturization...
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Modeling of multi-cavity Fabry-Perot optical fiber sensors
PublicationReflectance characteristics of a two-cavity extrinsic Fabry-Perot optical fiber sensor were investigated using computer modeling. Calculations were performed using a plane wave-based approach, selected for clarity of results. Based on the modeling results, it can be concluded that the two-cavity Fabry-Perot interferometer can be used to measure two different quantities, such as refractive index and temperature, independently. It...
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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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The Effect of Water and Frost on Fatigue Life of Asphalt Concrete
PublicationThis paper presents testing of fatigue life of asphalt concrete that has been subjected to action of water and frost. Simulation of water and frost action was based on the original AASHTO T283 method and its modification. The original method was modified in such a way that instead of a single freeze-thaw cycle, 50 and 150 cycles were applied. Fatigue life was measured in the indirect tensile fatigue test in the Nottingham asphalt...
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Estimation of time-frequency complex phase-based speech attributes using narrow band filter banks
PublicationIn this paper, we present nonlinear estimators of nonstationary and multicomponent signal attributes (parameters, properties) which are instantaneous frequency, spectral (or group) delay, and chirp-rate (also known as instantaneous frequency slope). We estimate all of these distributions in the time-frequency domain using both finite and infinite impulse response (FIR and IIR) narrow band filers for speech analysis. Then, we present...
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ANN for human pose estimation in low resolution depth images
PublicationThe paper presents an approach to localize human body joints in 3D coordinates based on a single low resolution depth image. First a framework to generate a database of 80k realistic depth images from a 3D body model is described. Then data preprocessing and normalization procedure, and DNN and MLP artificial neural networks architectures and training are presented. The robustness against camera distance and image noise is analysed....
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Low Power Baseband Processor for M2M Reconfigurable Radio Test Platform
PublicationSoftware Defined Radio (SDR) is becoming more andmore frequently used technique for wireless communication. Itfacilitates as fast prototyping and is a versatile method fordeveloping new communication systems. SDR can be realizedbased on high computational capacity platform, where powerconsumption is no a primary concern like i.e. DVB or BTStransmitters. Another trend are low power systems, whereavailable power in reduced and more...
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Low temperature deposition of dense MnCo 2 O 4 protective coatings for steel interconnects of solid oxide cells
PublicationIn this work manganese cobalt spinel (MnCo2O4) coatings were deposited on steel substrates by spray pyrolysis at 390 °C. This is at much lower temperatures than previously reported (typically in excess of 900 °C). It was possible to produce coatings with well controlled thickness (2-5-10 μm). The as-deposited coatings were evaluated for their microstructural changes and electrical conductivity up to 800 °C. Results confirm the...
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A spice equivalent circuit for modeling the performance of dual frequency echo-sounder
PublicationThe paper presents novel network equivalent circuit of piezoceramic circular disc transducers that takes into account thickness and radial mode of vibrations. The starting point of the analysis is 4-port description of circular disc element representing the solution of wave equation set in radial and thickness directions. The approximate solution for harmonic case is represented in the form of 4x4 matrix, which is synthesised and...
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Determination Of Gas Mixture Components Using Fluctuation Enhanced Sensing And The LS-SVM Regression Algorithm
PublicationThis paper analyses the effectiveness of determining gas concentrations by using a prototype WO3 resistive gas sensor together with fluctuation enhanced sensing. We have earlier demonstrated that this method can determine the composition of a gas mixture by using only a single sensor. In the present study, we apply Least-Squares Support-Vector-Machine-based (LS-SVM-based) nonlinear regression to determine the gas concentration...