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Wyniki wyszukiwania dla: direction of arrival estimation
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efficient fractional delay hilbert transform filter in the farrow structure
PublikacjaIn this paper the design and application of a Fractional Delay Hilbert Transform Filter (FDHTF) into an adaptive sub-sample delay estimation between two separated sinusoidal signals is considered. The FDHTF incorporates the functions of Hilbertian and variable fractional delay filtering of the incoming signal simultaneously, in one stage. In traditional approach each of these operations was performed separately. Obtained value...
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Automatic evaluation of information credibility in Semantic Web and Knowledge Grid
PublikacjaThis article presents a novel algorithm for automatic estimation of information credibility. It concerns information collected in Knowledge Grid and Semantic Web. Possibilities to evaluate the credibility of information in such structures are much greater than those available for WWW sites which use natural language. The rating system presented in this paper estimates credibility automatically on the basis of the following metrics:...
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New Approach to Noncasual Identification of Nonstationary Stochastic FIR Systems Subject to Both Smooth and Abrupt Parameter Changes
PublikacjaIn this technical note, we consider the problem of finite-interval parameter smoothing for a class of nonstationary linear stochastic systems subject to both smooth and abrupt parameter changes. The proposed parallel estimation scheme combines the estimates yielded by several exponentially weighted basis function algorithms. The resulting smoother automatically adjusts its smoothing bandwidth to the type and rate of nonstationarity...
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A novel concept for tissue-metal detection and differentiation using an inductive proximity sensor
PublikacjaIn this paper a novel application of inductive proximity sensors for detection of living tissue by means of measurements of the coil impedance changes at different frequencies is described. The mathematical analyses utilizing Bessel function estimation include detected object size and its distance from a sensor. The main aim of this study is to prove the possibility of distinguishing between metal objects and living tissues. The...
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Problems of Determination of Welding Angular Distortions of T-fillet Joints in Ship Hull Structures
PublikacjaShip hull structure elements are in majority joined by welding. Welding distortions can cause a lot of problems during the manufacturing process. In the literature it is proposed wide spectrum of suggestions for a correct estimation of welding deformation in particular angular deformation in the fillet welded T joint. In the work verification of selected methods is proposed basing upon of the results of the laboratory measurements....
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State Observer for Doubly-fed Induction Generator
PublikacjaIn the paper a new state observer for doubly-fed generator has been proposed. In the new approach an extended mathematical model of the doubly fed generator is used to form equations of the introduced z type observer. Stability of the observer has been verified through poles placement analyses. The active and reactive powers of the generator are controlled by a nonlinear multiscalar control method. Simulation and experimental results...
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Mechanical properties of Precontraint 1202 S2 based on uniaxial tensile and creep tests
PublikacjaThe purpose of the paper is the estimation of the polyvinyl chloride – polyester-coated fabric (Precontraint 1202 S2) mechanical properties under uniaxial tensile tests as well as short- and long-time creep tests. The uniaxial tests are the basis of non-linear elastic description while the creep tests are used for the evaluation of the stiffness parameters in time and for the identification of the standard viscoelastic model. The...
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SIMULATION MODEL OF ASON/GMPLS ARCHITECTURE
PublikacjaGrowing demands of information society concerned with sophisticated applications could be satisfied by ASON/GMPLS architecture comprehended as Automatically Switched Optical Network (ASON) with Generalized Multi-Protocol Label Switching (GMPLS). The ASON/GMPLS proposition represents the future direction of Next Generation Network (NGN) architecture. Therefore considerable work has to be done to examine this solution. In this aspect...
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Low-energy positron scattering from gas-phase tetrahydrofuran: A quantum treatment of the dynamics and a comparison with experiments
PublikacjaIn this paper we report new quantum calculations of the dynamics for low-energy positrons interacting with gaseous molecules of tetrahydrofuran. The new quantum scattering cross sections are differential and integral cross sections at collision energies between 1.0 and 25.0 eV and include a careful treatment of the additional effects on the scattering process brought about by the permanent dipole moment of the target molecule....
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The modelling method of discrete-continuous systems
PublikacjaThe paper introduces a method of discrete-continuous systems modelling. In the proposed method a three-dimensional system is divided into finite elements in only two directions, with the third direction remaining continuous. The thus obtained discrete-continuous model is described by a set of partial differential equations. General difference equations of discrete system are obtained using the rigid finite element method. The limit...
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INVESTIGATION OF JOURNAL SLIDE BEARINGS UNDER THE ANGLE OF THEIR FUNCTIONING
PublikacjaPaper presents the structure and principle of operation of a stand for measurements of influence of the lubrication method and process on functioning of journal slide bearings in their various technical states. Measurements performed on the stand make it possible to take advantage of the new method of evaluating the influence of physical and chemical properties of lubricating oil on the coefficient of friction in the mixed friction...
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Connectivity Improvement in Wireless Sensor Networks Using ESPAR Antennas with Dielectric Overlays
PublikacjaThis article presents an electrically steerable parasitic array radiator (ESPAR) switched beam antenna with a dielectric overlay to miniaturize the antenna and modify the radiation pattern in the vertical plane. The antenna is intended for a gateway in a wireless sensor network (WSN) and is located on the ceiling of a room. Because the ESPAR antenna consists of an array of vertical monopoles, there is a deep minimum in the radiation...
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Opracowanie procedury i badania wytrzymałościowe połączeń spawanych pomiędzy rurą kwadratowa a elementami giętymi na zimno ze stali S355 oraz testowanie połączeń o grubości 4, 6, 8mm typu S355
PublikacjaCelem pracy było: - opracowanie procedury badania wytrzymałości połączeń spawanych rozciąganych w kierunku prostopadłym i w kierunku równoległym (ścinanych) do osi spoiny. Spoiny te łączyły elementy rur kwadratowych o różnej grubości z elementami w kształcie ceownika giętymi na zimno. - wykonanie próbek do badań wytrzymałościowych wyciętych z elementów spawanych dostarczonych przez Zakład Produkcyjny firmy Borga obciążonych prostopadle...
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Application of Msplit method for filtering airborne laser scanning data sets to estimate digital terrain models
PublikacjaALS point cloud filtering involves the separation of observations representing the physical terrain surface from those representing terrain details. A digital terrain model (DTM) is created from a subset of points representing the ground surface. The accuracy of the generated DTM is influenced by several factors, including the survey method used, the accuracy of the source data, the applied DTM generation algorithm, and the survey...
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Application of the Msplitmethod for filtering airborne laser scanning data-sets to estimate digital terrain models
PublikacjaALS point cloud filtering involves the separation of observations representing the physical terrain surface from those representing terrain details. A digital terrain model (DTM) is created from a subset of points representing the ground surface. The accuracy of the generated DTM is influenced by several factors, including the survey method used, the accuracy of the source data, the applied DTM generation algorithm, and the survey...
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Efektywność przewodowego transportu paliw gazowych. Część 1
PublikacjaW pracy przeprowadzono badanie możliwości podwyższenia efektywności transportu rurociągowego gazu ziemnego. Przeanalizowano różnorodne aspekty z zakresu procedur projektowania. Zaproponowano modele określania kosztów kapitałowych (inwestycyjnych) i kosztów zmiennych. Określono równania jednostkowych kosztów całkowitych (rocznych), które poddano „quasi-optymalizacji”, w celu wyznaczenia średnic racjonalnych dla gazociągów.
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Efektywność przewodowego transportu paliw gazowych. Część 2
PublikacjaW pracy przeprowadzono badanie możliwości podwyższenia efektywności transportu rurociągowego gazu ziemnego. Przeanalizowano różnorodne aspekty z zakresu procedur projektowania. Zaproponowano modele określania kosztów kapitałowych (inwestycyjnych) i kosztów zmiennych. Określono równania jednostkowych kosztów całkowitych (rocznych), które poddano „quasi-optymalizacji”, w celu wyznaczenia średnic racjonalnych dla gazociągów.
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Au nanoparticles identifiction with the use of AFM Volta potential mapping
Dane BadawczeThe specific physical, chemical and electrochemical electrical properties of gold nanoparticles have led to their extensive use as high-performance chemical and biochemical sensors. The described properties relate to surface plasmon resonance, fluorescence quenching or enhancement, high electrical conductivity and light scattering. The described nanoparticles...
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Laser-textured cross-hatched surface topography analysis with evaluation of high-frequency measurement noise
PublikacjaThe precision of surface roughness determination using ISO 25178 parameters relies on various factors that directly impact the measurement process. In industry applications, the contactless roughness measurement reduces data collection time. However, it introduces several potential errors, including those stemming from the environment. One of the main types of errors encountered during topography analysis is measurement noise,...
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Investigation on stability of mountainous EUPOS sites’ coordinates
PublikacjaThe paper concerns analysis of solutions obtained during common processing of data from GNSS permanent stations situated on mountainous terrain: the Western Carpathians, the Sudetes Mountains and adjacent areas. As the outcome daily and weekly solutions (ellipsoidal coordinates) of forty Polish, Czech, Slovak, Ukrainian and German sites were obtained. Weekly solutions were used to determine velocity field and vertical movements,...
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Permeability of sandy soils estimated from particle size distribution and field measurements
PublikacjaAccurate estimation of soil permeability is crucial in many geotechnical applications. Empirical and theoretical equations based on soil particle size distribution (PSD) offer a fast and cheap way for preliminary estimation of permeability in granular soils, however the results obtained from various formulas available in the literature often show significant discrepancies. While several comparative studies on this topic have been...
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Selected Aspects of 3D Printing for Emergency Replacement of Structural Elements
PublikacjaThe paper presents a synthetic characterization of modern methods of manufacturing or regenerating machine elements. Considered methods are machining and additive methods, in particular 3D printing in the FDM/FFF technique. For the study, the authors made samples of the holder bracket using selected methods. Samples made by machining operations, 3D printing with various filling were tested. The paper contains a technical and economic...
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Compensation of Dead Time Effects for Shunt Active Power Filters
PublikacjaThe paper presents a comprehensive approach to the compensation of the grid current distortion for shunt active power filter systems. Four different sources of current distortion are addressed: imperfect grid synchronization caused by the distortion in the grid voltages, time delays in the estimation of compensating currents and grid voltages, fluctuations of the dc bus voltage, and the distortion of inverter output voltages due...
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Uncertainty analysis of measuring system for instantaneous power research
PublikacjaThe paper presents a metrological analysis of the measurement system used for diagnosis of induction motor bearings, based on the analysis of the instantaneous power. This system was implemented as a set of devices with dedicated software installed on a PC. A number of measurements for uncertainty estimation was carried out. The results of the measurements are presented in the paper. The results of the aforementioned analysis helped...
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Degradation of polyurethanes in Compost Under Natural Conditions
PublikacjaThe estimation of degradibility of different polyurethanes under natural weather depending conditions in compost pile was the subject of the studies. The incubation of polymer samples took place for a period up to 24 months. The characteristic parameters of the compost: temperature, pH, moisture content, and activity of dehydrogenasis were monitored and their influence on degradation of polyuiretahnes was discussed. The compostability...
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Properties and interpretation of Instantaneous Complex Frequency
PublikacjaThe concept of Instantaneous Complex Frequency (ICF) was first defined by Lindon and developed mainly in works of two authors S. Hahn and M. Rojewski. Although it is not widely used in signal analysis, ICF was already used as a complex signal representation in the verification of handwritten signatures, pitch estimation, symbol timing recovery in PSK receiver and in detection of anomalies in data transmission. It should be noted,...
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On bidirectional preestimates and their application to identification of fast time-varying systems
PublikacjaWhen applied to the identification of time-varying systems, such as rapidly fading telecommunication channels, adaptive estimation algorithms built on the local basis function (LBF) principle yield excellent tracking performance but are computationally demanding. The subsequently proposed fast LBF (fLBF) algorithms, based on the preestimation principle, allow a substantial reduction in complexity without significant performance...
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TDOA Navigation Using CDMA2000 Signals – Experimental Results
PublikacjaThis paper presents results of an experiments on the possibility to estimate position of a CDMA2000 receiver on the basis of TDOA measurements. The hardware and software structure of a navigation receiver used during investigation is briefly described with focus on drawbacks and limitations. The main part of this paper contains basic information about CDMA2000 network in northern Poland, which signals were recorded during tests...
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Profesor Stanisław Trzetrzewiński – polski prekursor niepewności pomiaru
PublikacjaArtykuł ma na celu przybliżenie sylwetki Profesora Stanisława Trzetrzewińskiego, jako pierwszego kierownika Katedry Miernictwa Elektrycznego na Wydziale Elektrycznym Politechniki Gdańskiej, odpowiedzialnego za organizację Katedry po wojnie, dydaktyka, ale przede wszystkim wybitnego metrologa. Profesora Stanisława Trzetrzewińskiego można nazwać polskim prekursorem teorii niepewności pomiaru, co potwierdza wygłoszony w 1952 roku...
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Structure of the interlayer between Au thin film and Si-substrate: Molecular Dynamics simulations
PublikacjaInteraction between 2, 3, 5 and 7 atomic layers of gold and a (111) silicon surface was investigated with the molecular dynamics simulation method. The simulation of the diffusion interaction between gold and silicon in the temperature range 425-925 K has been carried out. The peculiarities of the concentration changes of the interacting components and the atomic density at the boundary...
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Objectivization of audio-video correlation assessment experiments
PublikacjaThe purpose of this paper is to present a new method of conducting an audio-visual correlation analysis employing a head-motion-free gaze tracking system. First, a review of related works in the domain of sound and vision correlation is presented. Then assumptions concerning audio-visual scene creation are shortly described. The objectivization process of carrying out correlation tests employing gaze-tracking system is outlined....
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An Objective Focussing Measure for Acoustically Obtained Image
PublikacjaIn scientific literature many parameters of an image sharpness can be defined, that can be used for the evaluation of display energy concentration (EC). This paper proposes a new, simple approach to EC quantitative evaluation in spectrograms, which are used for the analysis and visualization of sonar signals. The presented approach of the global-image EC measure was developed to the evaluation of EC in arbitrary direction (or at...
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Integration of the Eurasian Economic Union in Comparison to European Union Integration
PublikacjaThe aim of the article is to show the specificity of the integration of the Eurasian Economic Union (EEU) on the example of the integration of the European Union (EU). The EEU is a relatively young grouping that was established in 2015 by Republic of Armenia, the Republic of Belarus, the Republic of Kazakhstan, the Kyrgyz Republic and the Russian Federation. Its creators try to give the Eurasian integration process a different...
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Augmented Reality for Privacy-Sensitive Visual Monitoring
PublikacjaThe paper presents a method for video anonymization and replacing real human silhouettes with virtual 3D figures rendered on the screen. Video stream is processed to detect and to track objects, whereas anonymization stage employs fast blurring method. Substitute 3D figures are animated accordingly to behavior of detected persons. Their location, movement speed, direction, and person height are taken into account during the animation...
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Water related esthetics - the phenomenon of new structure in the post industrial shipyard areas
PublikacjaDirection of the main movements that are made in the European cities determines not only structural but also an esthetic changes. Paper follows the topic of visual diversity of post industrial waterfront cities and it’s relation to the local identity and cultural changes that are provided. Reshaping of the cities continuously proceed. Are those changes related with industrial shipyard districts only economical and spatial or also...
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Badanie i analiza efektywności alokacji strumieni danych w heterogenicznej sieci WBAN
PublikacjaW niniejszej dysertacji doktorskiej poddano dyskusji efektywność alokacji strumieni danych w heterogenicznej radiowej sieci WBAN (Wireless Body Area Networks). Biorąc pod uwagę dynamiczny rozwój nowoczesnych sieci radiokomunikacyjnych piątej generacji (5G), którego część stanowią radiowe sieci działające w obrębie ciała człowieka, bardzo ważnym aspektem są metody maksymalizujące wykorzystanie dostępnych zasobów czasowo –częstotliwościowych...
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Path Loss Modelling for Location Service Applications
PublikacjaThe aim of this paper is the path loss modeling for the radiolocation services in radiocommunication networks, particularly in cellular networks. The main results of the measurements obtained in the physical layer of the UMTS are introduced. A new method for the utilization of the multipath propagation phenomenon to improve the estimation of the distance between the mobile station (MS) and the base station (BS) is outlined. This...
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THE INFLUENCE OF MANUFACTURING OVERSIZING ON POSTWELDING DISTORTIONS OF THE FILLET WELDED JOINT
PublikacjaWelding proces is basic joining technique in shipbuilding. Such method generated welding distortions which cause a lot of problems during the manufacturing process. In the literature it is proposed wide spectrum of suggestions for a correct estimation of welding deformation in particular angular deformation in the fillet welded T joint. In the work influence of oversizing of weld on angular distortions of joint is presented basing...
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Discrete random variables in reliability calculations of a reticulated shell
PublikacjaImplementation of the Point Estimation Method (PEM) in the reliability analysis of a three-dimensional truss structure is presented in the paper. The influence of geometric and material random parameters on the truss load-carrying capacity was investigated. The analysis was performed for different combinations of basic variables. Symmetric and asymmetric cases of snow load were taken to assess the structural reliability. Sensitivity...
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Evaluation of expanded uncertainty of instantaneous power measurement in a bearing diagnostic system.
PublikacjaThe paper presents the issues concerning the estimation of the expanded uncertainty in the system for the diagnosis of rolling bearings, consisting of transducers: voltage and current voltage, which is used for diagnostic bearing motors method based on the measurement and analysis of the instantaneous power signal consumed by the induction motor. It presents the methodology for assessing the measurement uncertainty and presents...
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Parallel frequency tracking with built-in performance evaluation
PublikacjaThe problem of estimation of instantaneous frequency of a nonstationary complex sinusoid (cisoid) buried in wideband noise is considered. The proposed approach employs a bank of adaptive notch filters, extended with a nontrivial performance assessment mechanism which automatically chooses the best performing filter in the bank. Additionally, a computationally attractive method of implementing the bank is proposed. The new structure...
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Influence of Flat Lapping Kinematics on Machinability of Ceramics
PublikacjaNew tools for flat grinding of ceramics are presented in the paper. Electroplated CBN tools (B64 and B107) were used in a modified single-disc lapping machine configuration. The results from experiments, such as the material removal rate and surface roughness parameters are presented and analyzed. Numerical simulations, based on the model for the shape error and tool wear estimation in machining with flat lapping kinematics, are...
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Generalized Savitzky–Golay filters for identification of nonstationary systems
PublikacjaThe problem of identification of nonstationary systems using noncausal estimation schemes is consid-ered and a new class of identification algorithms, combining the basis functions approach with localestimationtechnique,isdescribed.Unliketheclassicalbasisfunctionestimationschemes,theproposedlocal basis function estimators are not used to obtain interval approximations of the parametertrajectory, but provide a sequence of point...
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BIG DATA SIGNIFICANCE IN REMOTE MEDICAL DIAGNOSTICS BASED ON DEEP LEARNING TECHNIQUES
PublikacjaIn this paper we discuss the evaluation of neural networks in accordance with medical image classification and analysis. We also summarize the existing databases with images which could be used for training deep models that can be later utilized in remote home-based health care systems. In particular, we propose methods for remote video-based estimation of patient vital signs and other health-related parameters. Additionally, potential...
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The Concept of Geodetic Analyses of the Measurement Results Obtained by Hydrostatic Leveling
PublikacjaThe article discusses the issue of hydrostatic leveling. Its application is presented in structural health monitoring systems in order to determine vertical displacements of controlled points. Moreover, the article includes a complete computation scheme that utilizes the estimation from observation differences, allowing the elimination of the influence of individual sensors’ systematic errors. The authors suggest two concepts of...
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Path Loss Modelling in the Untypical Outdoor Propagation Environments
PublikacjaIn the paper three ways of path loss modelling in the untypical outdoor environments are presented. The exemplary untypical outdoor environment is analyzed. The investigated environment is characterized, and the measurement campaign are shortly described. The following models have been analyzed: the COST231 Walfisch-Ikegami model, the modified COST231Walfisch-Ikegami model tuned on the basis of empirical data, and the empirical...
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LINEAR CHARACTERISTICS OF THE SLOSHING PHENOMENON FOR THE PURPOSE OF ON-BOARD SHIP'S STABILITY ASSESSMENT
PublikacjaThe paper presents results of experimental research and numerical simulations of the sloshing phenomenon. The research was focused on computation of the heeling moment affecting stability of a vessel. The proposed linearisation enables application of the results to the assessment of the ship's stability. The dependence of the heeling moment upon localisation of a tank in the ship's hull is analysed. The heeling moment obtained...
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Analysis of the parameters of respiration patterns extracted from thermal image sequences
PublikacjaRemote estimation of vital signs is an important and active area of research. The goal of this work was to analyze the feasibility of estimating respiration parameters from video sequences of faces recorded using a mobile thermal camera. Different estimators were analyzed and experimentally verified. It was demonstrated that the respiration rate, periodicity of respiration, and presence and length of apnea periods could be reliably...
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Reliability of Pulse Measurements in Videoplethysmography
PublikacjaReliable, remote pulse rate measurement is potentially very important for medical diagnostics and screening. In this paper the Videoplethysmography was analyzed especially to verify the possible use of signals obtained for the YUV color model in order to estimate the pulse rate, to examine what is the best pulse estimation method for short video sequences and finally, to analyze how potential PPG-signals can be distinguished from...
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Experimental study on plate modal parameters
PublikacjaTest doświadczalny jest częścią systemu diagnostycznego. Autorzy badają wpływ dodatkowej masy na parametry modalne wolno popartej stalowej płytyi. Artykół przedstawia technikę wyznaczania parametrów modalnych dla systemów monitorowania konstrukcji.The experimental test introduced in the paper is the part of the diagnostic system. The authors investigate the influence of the additional mass on modal parameters of simply supported...