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Wyniki wyszukiwania dla: measurement methods
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The measurement and calculation of gas temperature inside a switchgear during fault arc period.
PublikacjaW artykule przedstawiono metodę obliczania temperatury gazu wewnątrz rozdzielnicy szczelnej z izolacją powietrzną podczas zwarć łukowych w oparciu o równanie przewodnictwa cieplnego. Przedstawiono wyniki badań eksperymentalnych temperatury gazów podczas zwarć z łukiem wędrującym. Opisano model do badań, układ probierczy i warunki badań. Wyniki obliczeń porównano z wynikami badań eksperymentalnych.
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Time domain diagnosis of anticorrosion coatings via shape designed measurement signals.
PublikacjaW pracy przedstawiono operującą w dziedzinie czasu metodę diagnostyki pokryć przeciwkorozyjnych, na poziomie identyfikacji parametrów obwodu zastępczego. Metoda jest oparta na pobudzeniu obiektu sygnałem niekonwencjonalnym o projektowanym kształcie i pomiarze odpowiedzi obiektu (tzw. obserwabla) po upływie zadanego czasu T. Parametry obwodu zastępczego są obliczane bezpośrednio z obserwabli na podstawie równań wynikających z topologii...
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Accelerated impedance spectrum measurement via multisine perturbationand digital filter banks
PublikacjaPrzedstawiono przyspieszoną metodę pomiaru widma impedancyjnego, zorientowaną na pomiary jakości powłok przeciwkorozyjnych, modelowanych liniowymi obwodami zastępczymi. Metoda polega na pobudzeniu układu wielosinusoidalnym sygnałem popudzającym oraz analizie pobudzenia i odpowiedzi obiektu przez bank filtrów cyfrowych. Przedstawiono podstawy teoretyczne metody oraz propozycję metodologii pomiaru. Przeanalizowano wyniki symulacji...
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Example of practical use of vibration measurement results - study of settlement of the Wisłoujście Tower
PublikacjaW pracy przedstawiono wyniki identyfikacji parametrów posadowienia wieży Twierdzy Wisłoujście. Badanie oparto na zidentyfikowanych w pomiarach częstotliwościach drgań swobodnych wieży. Przyjęto prosty model dynamiczny obiektu, dobrze opisujący jego zachowanie.
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Influence of the analyzing window on electrode impedance measurement by thecontinuous freqency scanning method
PublikacjaPrzeprowadzono pomiary impedancyjne modelowego układu elektrycznego RC techniką ciągłego skanowania częstotliwościowego. Wyznaczono impedancję modelowego układu dla różnych okien analizujących oraz ich różnych wielkości. Wyznaczone dla różnych okien analizujących wartości R i C porównywano z wartościami rzeczywistymi. Stwierdzono wpływ rodzaju okna analizującego oraz jego długość na dokładność otrzymywanych wyników.
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Induction Motor Multiscalar Model Based Sensorless Control Using Power Measurement
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Influence of the analyzing window on electrode impedance measurement by the continuous frequency scanning method
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Measurement invariance of the Belief in a Zero‐Sum Game scale across 36 countries
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<title>Modeling of noncontact temperature measurement system using multiwavelength pyrometry</title>
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Measurement of sub-nanometer molecular layers with ISFET without a reference electrode dependency
PublikacjaA new method of detection and measurement with sub-nanometer resolution of layers adsorbed or bonded to the ISFET's gate dielectric was presented. The sensitivity of this method is high enough to detect even partial mono-layer covering. The transconductance measurement of the ISFET provides independence of the output signal from pH changes and the driving electrode electrochemical potential instabilities. The stable reference electrode...
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Sweet Cherry Skin Colour Measurement as an Non-Destructive Indicator of Fruit Maturity
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Energy Recovery Analysis in A-Type Pressure Regulation and Measurement Stations in Istanbul, Esenyurt
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Application of Maximum-Length Sequences to impulse response measurement of hydroacoustic communications systems
PublikacjaThere is a growing interest in digital transmission of telemetry data on ultrasonic waves. The dependence of signal attenuation on squared frequency, specific to the hy-droacoustic systems, induces problems that do not exist in monochromatic, narrowband radio communications systems. For adapting the transmission parameters to current propagation conditions, a precise knowledge of instantaneous changes of channel performances is...
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Evaluation of a 10 nm Particle Number Portable Emissions Measurement System (PEMS)
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Measurement of ethylene production as a method for determining the optimum harvest date of ‘Jonagored’ apples
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Measurement and Analysis of the Radio Wave Polarisation in Off-Body Communications in Indoor Environment
PublikacjaThe paper describes an analysis of the radio wave polarisation in off-body communications in indoor environment. The measurement stand for polarisation measurements has been shortly described. Five investigated scenarios with different body postures and different antenna placements have been characterize. The vertical and horizontal components of received radio signal have been analysed. The measure used in analysis is a ratio...
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Velocity measurement using the fdoa method in ground-based radio navigation system
PublikacjaVelocity is one of the main navigation parameters of the moving objects. However some systems of position estimation using radio wave measurements cannot provide velocity data due to limitation of their performance. In this paper a velocity measurement method for DS-CDMA radio navigation system is proposed, which doesn’t require full synchronization of reference stations carrier frequencies. The article presents basics of FDOA...
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Miniaturized passive emission test chamber for in-situ measurement of emissions of organic compounds
PublikacjaThe results of many different studies have demonstrated unequivocally that the quality of indoor air is often much worse than that of atmospheric air (outdoor). One of the main groups of chemical compounds present in indoor air, with proven harmfulness to health,are volatile organic compounds (VOCs). VOCs present indoor comprise a wide variety of hydrocarbons and hydrocarbons derivatives including aliphatic, aromatics, alkylbenzens,...
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Fault loop impedance measurement in low voltage network with residual current devices
PublikacjaW sieciach i instalacjach niskiego napięcia z wyłącznikami różnicowoprądowymi pomiar impedancji pętli zwarciowej jest kłopotliwy. Prąd pomiarowy powoduje ich zbędne zadziałanie, co uniemożliwia prawidłowe wykonanie pomiaru. W artykule omówiono przyczyny zbędnego zadziałania wyłączników różnicowoprądowych podczas pomiaru impedancji pętli zwarciowej oraz warunki, w jakich ten pomiar można wykonać poprawnie.
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Investigation of Weigh-in-Motion Measurement Accuracy on the Basis of Steering Axle Load Spectra
PublikacjaWeigh-in-motion systems are installed in pavements or on bridges to identify and reduce the number of overloaded vehicles and minimise their adverse eect on road infrastructure. Moreover, the collected trac data are used to obtain axle load characteristics, which are very useful in road infrastructure design. Practical application of data from weigh-in-motion has become more common recently, which calls for adequate attention to...
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Comparison of Different Measurement Techniques as Methodology for Surveying and Monitoring Stainless Steel Chimneys
PublikacjaThe measurement of a chimney axis is an engineering geodesy task. These measurements allow to assess the technical condition of chimneys and are usually carried out for reinforced concrete chimneys. When measuring high chimneys, the main problem may be the need to go a long distance to take a measurement. The surface of the chimney can also be problematic because it can absorb so much light from the range finder that total station...
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FIBRE-OPTIC SENSOR FOR SIMULTANEOUS MEASUREMENT OF THICKNESSAND REFRACTIVE INDEX OF LIQUID LAYERS
PublikacjaIn this paper, we present a fibre-optic sensor for simultaneous measurement of refractive index and thickness of liquid layers. We designed an experimental low-coherence setup with two broadband light sources and an extrinsic fibre-optic Fabry–Pérot interferometer acting as the sensing head. We examined how the refractive index of a liquid film and its thickness affect spectrum at the output of a fibre-optic interferometer. We...
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Fault Loop Impedance Measurement in Circuits Fed by UPS and Principle of Safety Protection
PublikacjaThis paper indicates a significant problem of uncertainty of fault loop impedance (FLI) measurement in circuits powered from uninterruptible power supply (UPS) (double-conversion AC-DC-AC). The correctly determined value of this impedance, related to the short-circuit current disconnection time and to the reference value, is one of the most important elements that determines the approval of an electrical installation and its receivers...
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Determination of the tram track axis using a multi receiver GNSS measurement system
PublikacjaThis article refers to research, that has been conducted by an interdisciplinary research team from the Gdańsk University of Technology and the Maritime University in Gdynia since 2009. These investigation concerns the determination of a railway track axis using the mobile satellite measurement technique. Following the dynamic development of GNSS techniques, that could be seen in the last decade, the team carried out further experiments...
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Measurement of expenditure efficiency of Polish cities with county rights in the context of quality of life
PublikacjaThe article is devoted to the measurement of efficiency of overall expenditures. The purpose of the study is to evaluate the efficiency of use of budget resources by local government units in the context of fostering quality of life. The subject of the study is 65 Polish cities with county rights (county status). Calculations were carried out using Data Envelopment Analysis (DEA). The results of analysis confirm the two research...
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Research on flue gas flow measurement and modelling in the moving grate biomass boiler
PublikacjaThe aim of this research was to determine the nature of gas flow in a grate boiler model by the method of Particle Image Velocimetry (PIV) and CFD. The paper presents the comparison of the PIV results with numerical simulations made in the environment of ANSYS Fluent. The main goal of the experiment was to describe the phenomena occurring on the grate. Methodology of modelling solid fuel combustion on the moving grate was proposed...
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Modelling and Measurement of Folk Guitar: Truss Rod and Strings in Numerical Analysis of Tone
PublikacjaThe study makes an attempt to model a complete vibrating guitar including its non-linear features, specifically the tension-compression of truss rod and tension of strings. The purpose of such a model is to examine the influence of design parameters on tone. Most experimental studies are flawed by uncertainties introduced by materials and assembly of an instrument. Since numerical modelling of instruments allows for deterministic...
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INFLUENCE OF WRONGLY ASSUMED PROBABILITY DISTRIBUTION ON THE UNCERTAINTY OF RESISTANCE MEASUREMENT BY TECHNICAL METHOD
PublikacjaThe paper presents studies on the influence of probability distributions on the expanded uncertainty of the resistance measurement. Choosing the correct probability distribution is very important to estimate of measurement uncertainty. The most commonly used distribution is the rectangular distribution. The paper presents the results of analysis of the resistance measurement uncertainty using the technical method of two resistances:...
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Challenges in oscillometric blood pressure measurement in atrial fibrillation: looking for practical solutions
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Low Frequency Noise Measurement of Reverse Polarized Silicon Carbide Schottky Diodes
PublikacjaW artykule przedstawiono wyniki pomiaró szumów cz. wstecznie spolaryzowanych diod Schottky'ego.
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Measurement of the earth fault loop impedance in a low voltage network with operating loads
PublikacjaW artykule przedstawiono problematykę dokładności pomiaru impedancji pętli zwarciowej w sieciach z obciążeniami roboczymi. Klasyczne metody pomiarowe i mierniki mogą powodować błędy pomiaru przekraczające dopuszczalną wartość. Z tego powodu może wystąpić ryzyko porażenia prądem elektrycznym, ponieważ przy doziemieniu nie będzie spełniony warunek samoczynnego wyłączenia zasilania. Błędy pomiaru w sieci z obciążeniami roboczymi można...
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In-service measurement of the small wind turbine test stand for structural health monitoring
PublikacjaThis paper presents the research activity performed on a Small Wind Turbine (SWT) test stand. Commercially available turbine was modified towards incorporation of the sensors system for condition monitoring. Installed sensors measure angular shaft position, torque applied from the wind loads, vibration accelerations and last but not least rotational speed. All gathered data are then transferred and processed in Test.Lab by means...
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Determination of magnetisation conditions in a Double-Core Barkhausen Noise measurement set-up
PublikacjaThe 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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Measurement of distance, velocity and angle of arrival using FMCW-CW combined waveform
PublikacjaA procedure of tacking small flying object based on a general principle of FMCW and Doppler radar is presented. In order to increase measurement range, this technique uses active signal source on the moving object. For simultaneous measurements of distance, radial velocity and direction (AoA) as well as simplified synchronization a combined FMCW-CW waveform is proposed. The presented measurement system was realized and verified...
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The measurement of input power of power supply in network disturbed by low frequency distortions
PublikacjaIn the paper authors present results of observation of input power changes versus harmonics amplitude in supply voltage of low-power power supply device. In the study, the electrical measurements supported with thermal imaging were used. The input circuit elements of studied device responsible for input power increase are pointed
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MEASUREMENT AND ANALYSIS OF A FLOOD WAVE PROPAGATION ON THE KACZA RIVER IN GDYNIA IN NORTHERN POLAND
PublikacjaKacza river is located in northern Poland in the neighborhood of the Gulf of Gdansk and the Baltic Sea. A Kacza having length of 15 km and catchment area of 53 km2 collects the water into the Gulf mostly from inhabited and forested areas within the administrative boundaries of the city of Gdynia. On the 14th and 15th of July 2016 in northern Poland on the large area of Tri-City agglomeration (Gdynia, Gdansk and Sopot) total daily...
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Analysis of distance measurement errors in CW FM sonar with MLS code modulation
PublikacjaAlthough used in the classic silent sonar, the CW FM sounding signal has a major flaw which is its inaccuracy in determining the distance to a target. The authors of the article have developed a concept of silent sonar using frequency modulation signals switched by pseudorandom codes, already discussed in their previous work. This article presents a detailed analysis of errors in CW FM sonar with pseudo-random sequence code modulation...
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Suppression of distortions in signals received from Doppler sensor for vehicle speed measurement
PublikacjaDoppler sensors are commonly used for movement detection and speed measurement. However, electromagnetic interference and imperfections in sensor construction result in degradation of the signal to noise ratio. As a result, detection of signals reflected from moving objects becomes problematic. The paper proposes an algorithm for reduction of distortions and noise in the signal received from a simple, dual-channel type of a Doppler...
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A method of earth fault loop impedance measurement without unwanted tripping of RCDs
PublikacjaIn low-voltage networks, earth fault loop impedance (EFLI) measurement is the basis for assessing the effectiveness of automatic disconnection of supply. Such a measurement is performed during initial and periodical verification, especially in a TN low-voltage network. Nowadays, due to widespread application of residual current devices (RCDs), such test is difficult in many circuits because RCDs operate during the test. In this...
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A High-Efficient Measurement System With Optimization Feature for Prototype CMOS Image Sensors
PublikacjaIn this paper, a gray-scale CMOS image sensor (CIS) characterization system with an optimization feature has been proposed. By using a very fast and precise control of light intensity, based on the pulsewidth-modulation method, it is avoided to measure the illuminance every time. These features accelerate the multicriteria CIS optimization requiring many thousands of measurements. The system throughput is 2.5 Gb/s, which allows...
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Miniaturized Passive Emission Chambers for In Situ Measurement of Emissions of Volatile Organic Compounds
PublikacjaThe results of many different studies have demonstrated unequivocally that the quality of indoor air is often much worse than that of atmospheric air. The presence of dangerous chemical compounds in indoor air can have an adverse impact on human health and cause numerous diseases of the respiratory and circulatory systems. Such harmful chemicals get into indoor air as a result of their emission from building and indoor materials....
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Measurement of magnetic signals of vehicles with denoising by matched filtering with FPGA FFT processor
PublikacjaW artykule przedstawiono realizację systemu do analizy i identyfikacji pojazdów oparty na pomiarze indukcji magnetycznej. Proponowany system może być zastosowany do wykrywania i identyfikacji pojadów zawierających elementy ferromagnetyczne, które zaburzają pole magnetyczne ziemi. Zaburzenie to można zmierzyć przy zastosowaniu trójosiowych magnetometrów transduktorowych, pracującyh w układzie różnicowycm. Zastosowano w systemie...
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Electrochemical Evaluation of Sustainable Corrosion Inhibitors via Dynamic Electrochemical Impedance Spectroscopy
PublikacjaFinding 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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System setup and software for cyclic, staircase and square wave voltammetry measurements
PublikacjaHardware dedicated for electrochemical measurement sometimes does not allow performing certain voltammetry experiments. Staircase and square wave voltammetry, techniques which have many advantages comparing with standard voltammetric techniques, are rarely implemented in software controlling electrochemical measuring equipment. These methods, however, can be relatively easy realized with some addition...
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An Instantaneous Engine Speed Estimation Method Using Multiple Matching Synchrosqueezing Transform
PublikacjaInstantaneous rotational speed measurement of the engine is crucial in routine inspection and maintenance of an automobile engine. Since the contact measurement of rotational speed is not always available, the vibration measurement has been used for noncontact rotational speed estimation methods. Unfortunately, the accuracy of the noncontact estimation methods by analyzing engine vibration frequency is not satisfactory due to the...
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Selected aspects of two-phase flow studies using different visualization techniques in minichannels
PublikacjaThe subject of the study is to present the possibility of the use of visualization techniques in the researches on two-phase flows, carried out by the authors for many years. These works included as follows: heat transfer during the flow boiling, boiling crises and condensation in flow. The issue of the heat transfer intensification during the flow boiling through the channels of small diameters was analyzed. All this work focused...
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Noninvasive method for rotor fault diagnosis in inverter fed induction motor drive
PublikacjaThis article presents a proposal, simulation and experimental results of a noninvasive rotor fault diagnosis method for the inverter fed induction motor drive. Comparing to reported methods the proposed one does not require any load, rotor brake, slip, mechanical or electrical system physical modification e.g. machine disassembly and can be applied regardless the rotor speed measurement or estimation method.
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Thermal, electrical, and magnetic properties of Fe2O3–PbO–SiO2 glass prepared by traditional melt-quenching and twin roller fast-cooling methods
PublikacjaIn this study, Fe–Pb–Si oxide glasses containing between 12.5 and 17.5 mol% Fe2O3 were prepared using two different methods comprising traditional melt-quenching and twin roller fast-cooling techniques. The topography and structure of the materials obtained were characterized by X-ray powder diffraction and scanning electron microscopy. All of the materials were found to be amorphous. The topography of most of the glasses comprised...
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MCSA with Normalized Triple Covariance as a bearings diagnostic indicator in an induction motor
PublikacjaStatistics of bearing failures in induction motors indicate, that they constitute more than 40% of IM damage, therefore bearing diagnosis is very important. Vibration methods for bearing diagnostics have one major disadvantage - they require the availability of the machine for sensors installation. This is the reason for seeking new methods based on motor supply current analysis. Diagnosis of induction motors, conducted remotely...
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Pomiar sił w wantach mostu podwieszonego
PublikacjaW artykule przedstawiono metodę oraz wyniki badań sił w wantach Mostu III Tysiąclecia im. Jana Pawła II w Gdańsku. Do identyfikacji sił wykorzystano trzy metody: wibracyjną; z wykorzystaniem siłownika jednosplotowego (lift-off) oraz pomiaru strzałki ugięcia. Przedstawione wyniki badań dowodzą, że wszystkie metody mogą być z powodzeniem wykorzystywane do identyfikacji rzeczywistej siły w wancie. Każda z metod ma jednak ograniczenia...