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Search results for: geodesic measurements
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Wpływ procedury termostatowania oraz sposobu przeprowadzenia pomiaru na wyniki oceny zawartość fazy stałej w wybranych tłuszczach.Influence of procedure of termostating and methods of measurements on solid fat content in selected fats.
PublicationW pracy przedstawiono sposoby przygotowania próbek tłuszczów przed oznaczeniem zawartości fazy stałej opracowane przez organizacje międzynarodowe oraz instytucje specjalizujące się w chemii i analizie tłuszczów. Porównano stosowane procedury termostatowania i metody pomiaru, oraz zbadano ich wpływ na zawartość fazy stałej w wybranych tłuszczach.
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Poziomy stężeń lotnych związków chlorowcoorganicznych w wodach opadowych na terenie dużej aglomeracji miejskiej = Measurement of volatile chloroorganic compounds in urban rainwater (Gdańsk, Sopot, Gdynia)
PublicationW 105 próbkach opadów atmosferycznych (deszcz, deszcz ze śniegiem) zebranych z terenu Trójmiasta w okresie od listopada 2000 r. do maja 2001 r. oznaczano chloro - i bromopochodne metanu, etanu i etenu (7 różnych związków). Najczęściej wykrywanymi i oznaczanymi były: chloroform i czterochlorek węgla, (bardzo popularne rozpuszczalniki stosowane jako środki chłodzące i czyszczące). Najwyższe stężenia obserwowano w przypadku chloroformu,...
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Measurement of activity coefficients at infinite dilution of organic solutes in the ionic liquid 1-hexyl-1,4-diaza[2.2.2]bicyclooctanium bis(trifluoromethylsulfonyl)imide using gas–liquid chromatography
PublicationBased on gas–liquid chromatography (GLC) retention data, activity coefficients at infinite dilution of 39 different solutes in the ionic liquid 1-hexyl-1,4-diaza[2.2.2]bicyclooctanium bis(trifluoromethylsulfonyl)imide ([HDABCO][NTf2]) have been determined. Measurements covered a broad range of types of organic solutes including alkanes, alcohols, ketones, benzene derivatives and McReynold’s compounds. Activity coefficients were...
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Estimation of transmission quality in cellular systems based on indicators measured by the radio module
PublicationThe article presents a measurement stand for testing transmission quality in cellular systems such as LTE, NB-IoT, UMTS and GSM. The results of BLER and throughput measurements for various propagation conditions as well as results of quality indicators appropriate for mentioned technologies measured by commercial radio module are presented. Those measurements were utilized to analyze the possibility of estimating the transmission...
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Pomiary naprężeń w warstwie wierzchniej stali duplex metodą dyfrakcji promieniowania rentgenowskiego g-sin2Ψ = Residual stress measurements in duplex steel surface layers by g-sin2Ψ x-ray diffraction method
PublicationPrzedstawiono wyniki pomiarów naprężeń w warstwie wierzchniej z wykorzystaniem metody dyfrakcji promieniowania rentgenowskiego g-sin2. Wyjaśniono zasady przeprowadzania pomiarów naprężeń na próbkach walcowych o małej średnicy. Badania prowadzono na próbkach okrągłych ze stali duplex, poddanych procesom nagniatania. Stwierdzono występowanie naprężeń ściskających w warstwach powierzchniowych wszystkich badanych próbek oraz istotne...
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Photogrammetry image-based approach for imperfect structure modelling and FE analysis
PublicationThis study aims to model and analyse imperfect tructures using real measurements, employing photogrammetry technique commonly used in the geodesy. The study highlights the capability of the photogrammetry in aiding the structural analysis of imperfect engineering objects. Firstly, the photogrammetry measurements of a stiffened plate are carried out using a specially designed for the purpose experimental stand. Then, the plate surface...
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Research project BRIK: development of an innovative method for determining the precise trajectory of a railway vehicle
PublicationIn the paper the essential assumptions regarding a research project implemented by a consortium of Gdansk University of Technology and Gdynia Maritime University are presented. The project has been commissioned by National Center of Research and Development with cooperation with Polish Railways (PKP Polskie Linie Kolejowe S.A.). The project is focused in implementation of modern measurement techniques using Global Navigation Positioning...
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Fiber-optic sensors based on microspheres with nanocoatings (Zastosowanie mikrosfer optycznych z cienkowarstwowymi pokryciami w czujnikach światłowodowych)
PublicationTemperature is one of the most important physical quantities. Temperature measurements are used in every field of life, especially electronics, electrical engineering, energy-related fields, including energy source and storage devices. The goal of this dissertation is to design and optimize the microsphere-based fiber-optic sensors construction for measurement of the sensor surrounding medium temperature, including selection of...
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Electrochemical capacitor temperature fluctuations during charging/discharging processes
PublicationThepaperpresentsaproposalofusingadditionalstatisticalparameterssuchas:standarddeviation,variance, maximum and minimum increases of the observed value that were determined during measurements of temperature fields created on the surface of the tested electrochemical capacitor. The measurements were carriedoutusingthermographicmethodsinordertosupportassessmentoftheconditionofelectrochemical capacitorunderclassicdurabilitytestsbasedonmethodsofdeterminationofcapacityandequivalentseries...
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Assessment of the Accuracy of a Virtual Multi-Channel Temperature Measuring Instrument
PublicationThe multi-channel temperature measurement system developed works with NTC thermistors. The article presents the results of theoretical and empirical evaluation of accuracy obtained in measurement channels. The basis for the theoretical assessment is the mathematical model for each of the measurement channels and the characteristics of the system elements included in the circuits of the measurement channel. Two different methods were...
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Adaptive acoustic crosstalk cancellation in mobile computer device
PublicationThe cancellation of acoustic crosstalk is employed to enhance the stereo image in mobile listening conditions. A practical setup employing a mobile computer is employed. The adaptation of the crosstalk cancellation filter to the position of the listener's head is featured. The measurement evaluating the possibility of practical application of the method are described. The head and torso simulator was used for measurements. The...
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O zastosowaniu metody prądów wirowych do technicznego pomiaru własności elektrycznych i magnetycznych metali = About application of eddy current method for technical measurement of electric and magnetic properties of metals
PublicationOpisano wyniki badań nad wykorzystaniem efektu prądów wirowych do badania własności elektrycznych i magnetycznych metali. Badania wykonano za pomocą sondy różnicowej. Wyniki pomiarów zależności częstotliwościowej wykonane dla modelowych materiałów porównano z wynikami modelowania metodą elementów skończonych.
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Analysis of the Accuracy of Pulse Estimation Using Smart Watches
PublicationThe purpose of this paper is to perform an analysis of the accuracy of the pulse estimation by comparing readings from a smartwatch with readings from medical devices. The study required writing applications that allow continuous pulse measurement. As a result, two applications were created for the smartwatch. The first one is dedicated to Android Wear devices, while the other one is compatible with Tizen watches. The next step...
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Satellite Laser Ranging technique as a tool for the determination of the Schwarzschild, de Sitter and Lense-Thirring effects
PublicationSatellite Laser Ranging (SLR) is a modern technique used in various research areas and applications related to geodesy and geodynamics. It is commonly used for tasks such as establishing the International Terrestrial Reference Frame (ITRF), monitoring Earth Orientation Parameters (EOP), determining the geocenter, measuring fundamental physical constants, calibrating microwave tracking techniques, conducting time transfer experiments,...
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Determining the leakage current resistive component by the orthogonal vector method
PublicationThe measurement of the metal – oxide surge arresters (MOSA) leakage current and the analysis of its components is a key diagnostic criterion according to technical standards. During on site MOSA condition assessment, the easy way is based on the measurement only leakage current, without the inconvenient live working measurements of supply voltage. Orthogonal vectors method of determination the resistive leakage current is presented....
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Szacowanie niepewności pomiarowej układu do diagnostyki łożysk opartej na analizie mocy chwilowej.
PublicationW artykule przedstawiono metodologię szacowania niepewności pomiarowej wykorzystanego do badań diagnostycznych łożysk silników indukcyjnych układu pomiarowego, składającego się z dzielnika napięcia oraz bocznika. Wyniki tych analiz pozwalają spre-cyzować, jakiej niepewności pomiarowej można się spodziewać, dokonując badań diagnostycznych łożysk silników indukcyjnych w określonych warunkach, na stanowisku badawczym metodą pomiaru...
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Szacowanie niepewności pomiarowej układu do diagnostyki łożysk opartej na analizie mocy chwilowej
PublicationW artykule przedstawiono sposób szacowania niepewności układu pomiarowego, składającego się z dzielnika napięcia oraz bocznika, który wykorzystano do badań diagnostycznych łożysk silników indukcyjnych. Wyniki analizy metrologicznej pozwalają sprecyzować, jakiej niepewności pomiarowej można się spodziewać, dokonując badań diagnostycznych łożysk silników indukcyjnych w określonych warunkach, na stanowisku badawczym metodą...
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Methodology for the Correction of the Spatial Orientation Angles of the Unmanned Aerial Vehicle Using Real Time GNSS, a Shoreline Image and an Electronic Navigational Chart
PublicationUndoubtedly, Low-Altitude Unmanned Aerial Vehicles (UAVs) are becoming more common in marine applications. Equipped with a Global Navigation Satellite System (GNSS) Real-Time Kinematic (RTK) receiver for highly accurate positioning, they perform camera and Light Detection and Ranging (LiDAR) measurements. Unfortunately, these measurements may still be subject to large errors-mainly due to the inaccuracy of measurement of the optical...
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Evaluation of the prediction ability of air pollutants based on the electronic nose responses
PublicationElectronic noses are able to perform on-line measurements of the toxic volatile compounds in air. Due to their low cost and compact size they can be placed in the areas exposed to pollution, outside the laboratory. Those advantages, on the other side, force the need for development of the reliable sensors data analysis procedures. One of the most important issues connected with electronic noses is the lack of stability of the gas...
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Angle Tracking Observer for Filtering Rotor Position Estimates in Sensorless Electric Drives
PublicationSensorless electric drives use measurements of electrical quantities to estimate rotor position and speed. Measurement errors deteriorate the estimation accuracy, thus additional means are necessary to remove high-frequency components from estimated signals. This paper proposes to use an Angle Tracking Observer (ATO) for reducing noise in rotor position estimates, which is related to random errors in the measurements. A simplified,...
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Profesor Stanisław Trzetrzewiński – polski prekursor niepewności pomiaru
PublicationArtykuł 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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Mesoscopic impedance analysis of solid materials surface
PublicationSeveral techniques have been developed in order to characterize electrical properties of surfaces in micrometer/nanometer scale. Obtaining of the spatial distribution of sample resistance, capacitance or potential requires separate measurements performed in different scanning modes. On the other hand, analysis of the frequency response of investigated system enables determination of several physical quantities in single measurement...
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Corrosion monitoring by harmonic analysis in aqueous environments
PublicationThis paper presents tests concerning the rate of corrosion in non-alloy steel (type S235JR) in an aqueous environment, with an additive of sodium chloride by means of polarization resistance measurements and harmonic analysis. The tests have been carried out for steel samples exposed to the testing environment for six weeks, in order to obtain a constant rate of corrosion in the function of time. The measurements have aimed at...
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Badania i analizy kolejowych konstrukcji odciążających typu mostowego
PublicationW pracy przedstawiono i omówiono wybrane modele obliczeniowe, wyniki analiz teoretycznych oraz badań trzech typów kolejowych konstrukcji odciążających typu mostowego. Zaprezentowano modele obliczeniowe oraz metodykę badań in situ tego typu konbstrukcji. Przedstawiono wnioski dotyczące zaawansowanych metod obliczeniowych rozszerzonych badań in situ w celu diagnozowania rzeczywistej pracy obiektów mostowych.
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Multi-Channel Virtual Instrument for Measuring Temperature—A Case Study
PublicationThe article presents the hardware and software configuration of the developed multi-channel temperature measurement system as well as calibration procedures and measurement results verifying the properties of measurement channels. The system has been developed and dedicated primarily for measuring the temperature distribution in a laboratory model simulating underground power lines. With the adopted configuration of the analog...
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A Comparison of STI Measured by Direct and Indirect Methods for Interiors Coupled with Sound Reinforcement Systems
PublicationThis paper presents a comparison of STI (Speech Transmission Index) coefficient measurement results carried out by direct and indirect methods. First, acoustic parameters important in the context of public address and sound reinforcement systems are recalled. A measurement methodology is presented that employs various test signals to determine impulse responses. The process of evaluating sound system performance, signals enabling...
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Multimedia System for Environmental Noise Monitoring. [Multimedialny System Monitorowania Hałasu Środowiskowego]
PublicationIntroductionNumerous reports relating to noise threats in Poland indicate that they occur commonly. The noise has an enormous impact on the health and life quality of the human beings. Noise pollution in Poland is greater than in others UE countries, moreover it has been increased recently. Taking into account 2002/49/WE directive related to the control and assessment of environmental noise a necessity of monitoring these threats...
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Estimating the uncertainty of the liquid mass flow using the orifice plate
PublicationThe article presents estimation of measurement uncertainty of a liquid mass flow using the orifice plate. This subject is essential because of the widespread use of this type of flow meters, which renders not only the quantitative estimation but also qualitative results of this type so those measurements are important. To achieve this goal, the authors of the paper propose to use the theory of uncertainty. The article shows the...
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Detection of person presence and its activity in the bathtub
PublicationA practical application of a bioimpedance technique for a detection of a bathing person is presented in the paper. It addresses the possibility of supervising people in the bathtub without voiding of their intimacy. The measurement system installed in a fiber-glass or a plastic bathtub is able to detect a presence of the bathing person, to estimate its activity and thus to detect potentially dangerous events. In the paper a principle...
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Analysis of Position Calculating Methods in Indoor Environment
PublicationIn the paper a modified gradient method has been proposed for position calculation on basis of distance measurement in indoor environment. It is shown that the well-known Chan method of position calculation is inefficient in indoor circumstances. Author presents Chan and modified gradient methods and achieved results for each one for real measurements.
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Lokalizacja osób w środowisku promu pasażerskiego z wykorzystaniem ultra szerokopasmowego interfejsu radiowego
PublicationW niniejszym artykule przedstawiono badania efektywności lokalizowania poruszających się osób w środowisku promu pasażerskiego stosując pomiar czasu propagacji ultraszerokopasmowego sygnału radiowego UWB (Ultra-Wide Band) pomiędzy węzłami odniesienia i terminalem ruchomym. Opisano zbudowane stanowisko badawcze oraz uzyskane wyniki pomiarów przeprowadzonych w warunkach rzeczywistych.
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Fast Fading Influence on the Deep Learning-Based LOS and NLOS Identificationin Wireless Body Area Networks
PublicationIn the article, the fast fading influence on the proposed DL (Deep Learning) approach for LOS (Line-of-Sight) and NLOS (Non-Line-of-Sight) conditions identification in Wireless Body Area Networks is investigated. The research was conducted on the basis of the off-body communication measurements using the developed mobile measurement stand, in an indoor environment for both static and dynamic scenarios. The measurements involved...
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Application of Least Squares with Conditional Equations Method for Railway Track Inventory Using GNSS Observations
PublicationSatellite geodetic networks are commonly used in surveying tasks, but they can also be used in mobile surveys. Mobile satellite surveys can be used for trackage inventory, diagnostics and design. The combination of modern technological solutions with the adaptation of research methods known in other fields of science offers an opportunity to acquire highly accurate solutions for railway track inventory. This article presents the...
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THE APPLICATION OF KALMAN FILTERING TO PREDICT VERTICAL RAIL AXIS DISPLACEMENTS OF THE OVERHEAD CRANE BEING A COMPONENT OF SEAPORT TRANSPORT STRUCTURE
PublicationAs the devices designed to transport materials, the overhead cranes should meet certain geometric requirements for their operation to be safe. The presently available geodetic equipment, in particular total stations, provides opportunities for precise 3D measurements of coordinates of the controlled points. These coordinates make a basis for correcting the height of crane runway axes. The paper presents a method to calculate position...
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Teledetekcyjne badanie konstrukcyjnych elementów żelbetowych z użyciem naziemnego skaningu laserowego
PublicationWspółczesna technologia naziemnego skaningu laserowego (TLS) z użyciem skanerów geodezyjnych o zasięgu większym niż 50 metrów pozwala na pomiar geometrii elementów konstrukcyjnych z dokładnością bliską 1 mm. Autorzy, w oparciu o badania laboratoryjne i doświadczenia własne, prezentują rozwiązanie pozwalające na wstępną ocenę belek żelbetowych jako podstawowych elementów konstrukcyjnych budowli typu mosty, wiadukty, budynki wielkopowierzchniowe. Przedmiotem...
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Propagation Path Loss Modeling in Container Terminal Environment
PublicationThis paper describes novel method of path loss modeling for radio communication channels in container port area. Multi-variate empirical model is presented, based on multidimensional regression analysis of real path loss measurements from container terminal environment. The measurement instruments used in propagation studies in port area are also described.
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Porous Phantoms Mimicking Tissues – Investigation of Optical Parameter Stability Over Time
PublicationIn terms of optical parameters, optical phantoms can now replace live tissues and be used to validate optical measurement methods. Therefore, whether these parameters would be maintained after storage for 6 months was examined. The absorption and scattering coefficients were obtained from the measured transmittance and reflectance measurements taken 6 months apart and then compared. All of the measurements were conducted using...
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The shallow sea experiment with usage of linear hydrophone array
PublicationPurpose of this article is to present designed and made linear hydrophone array and the results obtained during in situ trails on Gulf of Gdańsk. The measuring system allowed to localize hydrophones in the selected points and perform measurements in both the horizontal antenna positioning and vertical. Made in this way recordings allow creating accurate 3D imaging of sound intensity/propagation. During research three floating objects...
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Identification of Unstable Reference Points and Estimation of Displacements Using Squared Msplit Estimation
PublicationThe article presents a new version of the method for estimating parameters in a split functional model, which enables the determination of displacements of geodetic network points with constrained datum. The main aim of the study is to present theoretical foundations of Msplit CD estimation and its basic properties and possible applications. Particular attention was paid to the efficacy of the method in the context of geodetic...
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MEMS Gyro in the Context of Inertial Positionning
PublicationThe article undertake some vital aspect in geodesy, namely an inertial positioning problem using MEMS. Although MEMS inertial sensors offer affordable, appropriately scaled units, and though their inherent measurement noise can be relatively easily mitigated, there are still parameters due to they are not currently capable of meeting all requirements for the accurate and precise inertial positioning. The article presents crucial...
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Application of the Fractional Fourier Transform for dispersion compensation in signals from a fiber-based Fabry-Perot interferometer
PublicationOptical methods of measurement do not require contact of a probe and the object under study, and thus have found use in a broad range of applications such as nondestructive testing (NDT), where noninvasive measurement is crucial. Measuring the refractive index of a material can give a valuable insight into its composition. Low‑coherence radiation sources enable measurement of the sample’s properties across a wide spectrum, while...
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Third harmonic index as a diagnostic tool of high-voltage varistors
PublicationThe recommended methods for standard testing of high-voltage varistors demand application of high voltages and intensive currents that is inconvenient and needs extensive power consumption. These methods require metallization of the prepared ZnO structures that increases costs of testing. Another method of varistor quality and endurance evaluation by the third harmonic index measurement at relatively low voltage range has been...
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The decay of quantum correlations between quantum dot spin qubits and the characteristics of its magnetic-field dependence
PublicationWe address the question of the role of quantum correlations beyond entanglement in the context of quantum magnetometry. We study the evolution of the rescaled variant of the geometric quantum discord of two electron-spin qubits interacting with an environment of nuclear spins via the hyperfine interaction. We have found that quantum correlations display a strong magnetic-field sensitivity which can be utilized for decoherence-driven...
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In-situ optical diagnostics of boron-doped diamond films growth
PublicationInterferometry is a desirable method for in-situ measurement of thin, dielectric film growth, as it don't modify conditions of film deposition. Here we present interferometrical measurements of thickness of doped diamond films during Chemical Vapor Deposition (CVD) process. For this purpose we used a semiconductor laser with a 405nm wavelength. Additional ex-situ measurement using spectral interferometry and ellipsometry...
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Tuning of the finesse coefficient of optoelectronic devices
PublicationOptoelectronic devices attracted considerable attention in many branches of science and technology, which can be attributed to their unique properties. Many of them use optical cavities which parameters can be adopted to specific requirements. This thesis investigates the introduction of diamond structures (nitrogen-doped diamond film, boron-doped diamond film, undoped diamond sheet) to optical cavities to tune their finesse coefficient....
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Hydrodron — New Step for Professional Hydrography for Restricted Waters
PublicationHydrographic surveys in restricted areas are becoming increasingly important, but often impossible to carry out with conventional hydrographic vessels. Presumably in this case an employment of unmanned vehicles is the only reasonable solution. As restricted water areas include, among others: harbours, roadsteads, rivers or lakes. The HydroDron platform, due to its mobility, can operate in the above-mentioned areas. It is adapted...
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A probabilistic-driven framework for enhanced corrosion estimation of ship structural components
PublicationThe work proposes a probabilistic-driven framework for enhanced corrosion estimation of ship structural components using Bayesian inference and limited measurement data. The new approach for modelling measurement uncertainty is proposed based on the results of previous corrosion tests that incorporate the non-uniform character of the corroded surface of structural components. The proposed framework's basic features are outlined,...
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The Influence of LED Lighting Sources on the Nature of Power Factor
PublicationThis article presents measurements of electric power absorbed by a newly built facility for office and scientific research activities. These measurements highlighted the need for compensation of capacitive reactive power—not predicted by the designer—due to the vast use of LED lighting in the facility. The article also describes a reactive power compensation system, designed on the basis of the above-mentioned measurements, and...
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Photogrammetric and computerized report on site model in feasibility study of navigability channel on vistula spit
PublicationIn the report the authors present a course of geodesic and geo-computerized works upon realization of feasibility study of navigability channel on Vistula Spit. A procedure of acquiring verification and modeling of data for requirements of a numeric model of a bottom and site has been presented with construction of original software for 3D visualization of the Vistula Spit area. The activities described in the report can be...
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Projekt badawczy BRIK: Opracowanie innowacyjnej metody wyznaczania precyzyjnej trajektorii pojazdu szynowego
PublicationW artykule przedstawiono podstawowe informacje dotyczące projektu badawczego realizowanego na zlecenie Narodowego Centrum Badań i Rozwoju oraz Spółki PKP Polskie Linie Kolejowe S. A. przez Konsorcjum Politechniki Gdańskiej i Uniwersytetu Morskiego w Gdyni. Projekt obejmuje wykorzystanie nowoczesnych metod pomiarowych, takich jak techniki pozycjonowania satelitarnego GNSS, pomiary inercyjne INS oraz skaning laserowy LS, w procesie...