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Search results for: nauczanie metrologii
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Measurement microsystem for high impedance spectroscopy of anticorrosion coatings
PublicationW artykule przedstawiono mikrosystem do pomiarów bardzo dużych impedancji ukierunkowany na identyfikację parametrów powłok antykorozyjnych metodą spektroskopii impedancyjnej. Do wyznaczania składowych ortogonalnych sygnałów pomiarowych zastosowano w nim technikę cyfrowego przetwarzania sygnałów. Pozwoliła ona na uzyskanie szerokiego zakresu częstotliwości pomiarowych, zwłaszcza bardzo niskich, od ćHz, przy zachowaniu prostej konstrukcji...
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Conditions for measurement, analog-to-digital conversion and frequency analysis of irregularities of profile surface
PublicationPrzedstawiono uwarunkowania pomiaru, przetwarzania analogowo-cyfrowego i analizy częstotliwościowej nierówności powierzchni toczonych dla celów rozpoznawania ich głównych składowych. Przedstawiono ograniczenia w pomiarze igłą, która odwzorowuje nierówności poprzeczne. Podano zależności parametrów pomiaru cyfrowego nierówności warunkujące zakresy ich rozpatrywania. Dla wartości przedziału próbkowania, dla którego nie jest spełnione...
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Stereometry of turned surfaces in a frequency-domain formulation of profile irregularities
PublicationPrzedstawiono częstotliwościowe składowe nierówności powierzchni toczonych. Ponieważ nierówności mają charakter szerokopasmowy, trudny do wartościowania parametrami normatywnymi, zastosowano ich analizę amplitudowo-częstotliwościową, opartą na szybkiej transformacie Fouriera. Przedstawiono kształtowanie nierówności wzdłużnych dla toczenia. Zaproponowano oryginalny układ pomiaru sygnału przemieszczeń narzędzia względem przedmiotu...
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A method of identification of RTS components in noise signals
PublicationW artykule przedstawiono oryginalną metodę wydzielania szumu RTS (Random Telegraph Signal) - dwupoziomowego lub wielopoziomowego - z sygnału szumowego. Podstawą oceny jakości metody jest założenie, że wartości chwilowe szumu RTS mają rozkład niegaussowski natomiast pozostała część sygnału ma rozkład gaussowski.Algorytm identyfikacji wielopoziomowych szumów RTS w sygnałach szumowych małej częstotliwości oparty został na aproksymacji...
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An automatic system for identification of random telegraph signal (RTS) noise in noise signals
PublicationIn the paper the automatic and universal system for identification of Random Telegraph Signal (RTS) noise as a non-Gaussian component of the inherent noise signal of semiconductor devices is presented. The system for data acquisition and processing is described. Histograms of the instantaneous values of the noise signals are calculated as the basis for analysis of the noise signal to determine the number of local maxima of histograms...
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New concept of a measurement probe for high impedance spectrocopy
PublicationArtykuł przedstawia nową koncepcję sondy pomiarowej służącej jako obwód wejściowy analizatora do spektroskopii wysokoimpedancyjnej. Dzięki wykorzystaniu przetwornika prąd na napięcie uzyskano najmniejszy możliwy wpływ pojemności kabli dołączających mierzony obiekt na wynik pomiaru. Przeprowadzono analizę sondy biorąc pod uwagę najważniejsze parametry wpływające na dokładność pomiaru: pojemności pasożytnicze oraz rzeczywiste parametry...
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Stability of an optical displacement sensor using a two-beam polarization interferometer
PublicationW artykule przedstawiono wyniki pomiarów stabilności wybranej konfiguracji dwuwiązkowego interferometru polaryzacyjnego. Przedyskutowano źródła występującej niestabilności.
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Methods of quality characterization of foil-based capacitors
PublicationJakość kondensatorów wykonanych z folii aluminiowej jest zależna od wielu parametrów podczas ich produkcji. Istniejące metody oceny ich jakości nie są doskonałe. Stąd istnieje potrzeba propozycji nowych metod. W pracy przedstawiono wyniki badań zawartości trzeciej harmonicznej oraz emisji akustycznej występującej pod wpływem naprężenia mechanicznego zwijek foliowych z jakością wytworzenia tych zwijek.
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Quality assessment of high voltage varistors by third harmonic index
PublicationHigh voltage varistors that consist of grained ZnO have to be tested before assembling into a surge arrester. The existing methods demand a usage of high voltages and intensive currents that is inconvenient, destructive and needs extensive power consumption. Additionally, these methods require metallization of the prepared varistor structures that increases costs. We propose another method of varistors quality assessments by a...
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Nano-porous alumina humidity sensors
PublicationW pracy przedstawiono wyniki badań czujników wilgotności przygotowanych na bazie porowatej aluminy.
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Improvement of glass break acoustic signal detection via application of wavelet packet decomposition
PublicationThe main subject of the authors' research are non-contact methods of glass break detection based on analysis of the acoustic signal generated during the event. This problem has essential meaning for modern cost- effective alarm systems, particularly those installed into big buildings. The main difficulties of the matter are: transient character of the signal, great number of similar sounds (false signals, mainly accidental glass...
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Profile irregularities of turned surfaces as a result of machine tool interactions
PublicationThe paper describes the influence of the machining operation on a surface, which disturbs the projection of the tool profile in the form of its relative movements with respect to the object. The elements of the machine tool undergo constant wear during the machining process, it is therefore important to recognize the effects of their influence on the surface's irregularities. Amplitude-frequency analysis of lateral profiles has...
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Comparison of Tracking Methods in Respect of Automation of Animal Behavioral Test
PublicationAutomation in experiments carried out on animals is getting more and more important in research. Computers take over laborious and time-consuming activities like recording and analysing images of experiment scene. The first step in an image analysis is finding and distinguishing between the observed animals, and then tracking all objects during the experiment. In this paper four tracking methods are presented. Quantitative and...
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Mobile navigation system for visually impaired users in the urban environment
PublicationThis paper describes the prototype version of a mobile application supporting independent movement of theblind. Its objective is to improve the quality of life of visually impaired people, providing them with navigationalassistance in urban areas. The authors present the most important modules of the application. The module forprecise positioning using DGPS data from the ASG-EUPOS network as well as enhancements of positioning...
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Radio Link Measurement Methodology for Location Service Applications
PublicationThe aim of this paper is the methodology of measurements executed in a radio link for the realization of radiolocation services in radiocommunication networks, particularly in cellular networks. The main results of the measurements obtained in the physical layer of the universal mobile telecommunications system (UMTS) are introduced. A new method for the utilization of the multipath propagation phenomenon to improve the estimation...
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Ultrasonic spectroscopy of silicon single crystal
PublicationSpecimens of Si single crystals with different crystal orientation [100] and [110] were studied by the electro-ultrasonic spectroscopy (EUS) and Resonant Ultrasonic Spectroscopy (RUS). A silicon single crystal is an anisotropic crystal, so its properties are different in different directions in the material relative to the crystal orientation. EUS is based on interaction of two signals: electric AC signal and ultrasonic signal,...
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Liveness measurements using optical flow for biometric person authentication
PublicationAutomatyczne rozpoznawanie twarzy jest jedną z najpopularniejszych technik biometrycznych, jednak nawet najdokładniejsze algorytmy identyfikacji okażą się bezużyteczne, jeśli będzie można je oszukać, np. używając zdjęcia zamiast rzeczywistej osoby. Dlatego też odpowiedni pomiar żywotności jest niezwykle istotny. W pracy zaprezentowano metodę, która jest w stanie rozróżnić pomiędzy sekwencjami wideo pokazującymi żywe osoby oraz...
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Distance measurement errors in silent FM-CW sonar with matched filtering
PublicationThe secretiveness of sonar operation can be achieved by using continuous frequency-modulated sounding signalswith reduced power and significantly prolonged repeat time. The application of matched filtration in the sonarreceiver provides optimal conditions for detection against the background of white noise and reverberation, and avery good resolution of distance measurements of motionless targets. The article shows that target...
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Problems of varistor quality assessment during exploitation
PublicationVaristors are commonly used elements which protect power supply networks against high-voltage surges or lightning. Therefore, quality and endurance of these elements is important to avoid losses when an expensive laboratory equipment would not be protected from random overvoltages. Additionally, excessive leakage currents generate serious costs due to high energy consumption. The paper presents shortly properties of varistors that...
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Networked Object Monitor - A distributed system for monitoring, diagnostics and control of complex industrial facilities
PublicationRozwój mobilności i technologii internetowych, a także globalizacji gospodarki światowej, uwzględniający kluczowe aspekty zarządzania przepływem informacji, otworzył zupełnie nowe możliwości opracowywania i konstruowania innowacyjnych rozwiązań technicznych. Z taką myślą powstał prototyp Sieciowego Monitora Obiektu, aplikacji umożliwiającej nie tylko ciągłą kontrolę parametrów obiektów przemysłowych i biznesowych, ale również zarządzanie...
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Measurements of ASON/GMPLS connection control layer performance according to the ETSI methodology
PublicationMeasurements of performance have always been crucial for evaluation of telecommunication systems, especially for implementation of network control elements responsible for connection handling which regards to bandwidth reservation, modification and release. That problem also arises in Automatically Switched Optical Network/Generalized Multiprotocol Label Switching (ASON/GMLPS) architecture, which is considered as one of the components...
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The Effect Of Reference Plane On Values Of Areal Surface Topography Parameters From Cylindrical Elements
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Comparisons of envelope morphological filtering methods and various regular algorithms for surface texture analysis
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Potentiometric Oxygen Sensor with Solid State Reference Electrode
PublicationThe concentration or the partial pressure of oxygen in an environment can be determined using different measuring principles. For high temperature measurements of oxygen, ceramic-based sensors are the most practical. They are simple in construction, exploration and maintenance. A typical oxygen potentiometric sensor consists of an oxygen ion conducting solid electrolyte and two electrodes deposited...
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Velocity measurement using the fdoa method in ground-based radio navigation system
PublicationVelocity 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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Using A Particular Sampling Method for Impedance Measurement
PublicationThe paper presents an impedance measurement method using a particular sampling method which is an alternative to DFT calculation. The method uses a sine excitation signal and sampling response signals proportional to current flowing through and voltage across the measured impedance. The object impedance is calculated without using Fourier transform. The method was first evaluated in MATLAB by means of simulation. The method was...
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Emotion Monitoring – Verification of Physiological Characteristics Measurement Procedures
PublicationThis paper concerns measurement procedures on an emotion monitoring stand designed for tracking human emotions in the Human-Computer Interaction with physiological characteristics. The paper addresses the key problem of physiological measurements being disturbed by a motion typical for human-computer interaction such as keyboard typing or mouse movements. An original experiment...
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A method of RTS noise identification in noise signals of semiconductor devices in the time domain
PublicationIn the paper a new method of Random Telegraph Signal (RTS) noise identification is presented. The method is based on a standardized histogram of instantaneous noise values and processing by Gram-Charlier series. To find a device generating RTS noise by the presented method one should count the number of significant coefficients of the Gram-Charlier series. This would allow to recognize the type of noise. There is always one (first)...
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Current measurement and analysis for induction motor diagnostics
PublicationPrzedstawiono sposób diagnozowania łożysk tocznych w silnikach indukcyjnych z wykorzystaniem pomiarów i analizy prądu zasilającego silnik. Zaprezentowano metodę pomiarową i opracowania danych diagnostycznych. Uzyskano zgodność częstotliwości składowych widma prądu otrzymanych z badań teoretycznych i eksperymentalnych.Podano wyniki badań łożysk o róznych uszkodzeniach i prawdopodobieństwa poprawnych diagnoz.
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Distribution of roughness and waviness components of turned surface profiles
PublicationThe paper presents a spectral formulation of surface profile irregularity in a wideband frequency range for roughness, waviness and shape components along the measured length. A unique distribution of roughness and waviness components is proposed, according to the nature of their origination in the course of machining with tools of defined cutting edge, as distinct from standard filtration in measurements of surface irregularities....
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Electrochemical sensor for measurement of volatile organic compounds employing square wave perturbation voltage
PublicationThe paper presents the results of investigation on a prototype sensor for measurement of benzaldehyde in air. Sensitivity and limit of quantification of the sensor were determined for different internal electrolyte using the square wave voltammetry (SWV) as a detection technique. The working and counter electrodes were made of platinum. Ionic liquids 1-hexyl, 3-methylimidazolium chloride,1-hexyl, 3-methylimidazolium bis (trifluoromethanesulfonyl)...
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Algorithms of chemicals detection using raman spectra
PublicationRaman spectrometers are devices which enable fast and non-contact identification of examined chemicals. These devices utilize the Raman phenomenon to identify unknown and often illicit chemicals (e.g. drugs, explosives)without the necessity of their preparation. Now, Raman devices can be portable and therefore can be more widely used to improve security at public places. Unfortunately, Raman spectra measurements is a challenge...
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Efficiency of linear and non-linear classifiers for gas identification from electrocatalytic gas sensor
PublicationElectrocatalytic gas sensors belong to the family of electrochemical solid state sensors. Their responses are acquired in the form of I-V plots as a result of application of cyclic voltammetry technique. In order to obtain information about the type of measured gas the multivariate data analysis and pattern classification techniques can be employed. However, there is a lack of information in literature about application of such...
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Measurements of Spectral Spatial Distribution of Scattering Materials for Rear Projection Screens used in Virtual Reality Systems
PublicationRapid development of computing and visualisation systems has resulted in an unprecedented capability to display, in real time, realistic computer-generated worlds. Advanced techniques, including three-dimensional (3D) projection, supplemented by multi-channel surround sound, create immersive environments whose applications range from entertainment to military to scientific. One of the most advanced virtual reality systems are CAVE-type...
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Analogue CMOS ASICs in Image Processing Systems
PublicationIn this paper a survey of analog application specific integrated circuits (ASICs) for low-level image processing, called vision chips, is presented. Due to the specific requirements, the vision chips are designed using different architectures best suited to their functions. The main types of the vision chip architectures and their properties are presented and characterized on selected examples of prototype integrated circuits (ICs)...
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A family of new generation miniaturized impedance analyzers for technical object diagnostics
PublicationThe paper presents the family of three analyzers allowing to measure impedance in range of 10 ohm<|Zx|<10 Gohm in a wide frequency range from 10 mHz up to 100 kHz. The most important features of the analyzers family are: miniaturization, low power consumption, low production cost, telemetric controlling and the use of impedance measurement method based on digital signal processing DSP. The miniaturization and other above mentioned...
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A High-Efficient Low-Voltage Rectifier for CMOS Technology
PublicationA new configuration of rectifier suiting CMOS technology is presented. The rectifier consists of only two nchannel MOS transistors, two capacitors and two resistors; for this reason it is very favourable in manufacturing in CMOS technology. With these features the rectifier is easy to design and cheap in production. Despite its simplicity, the rectifier has relatively good characteristics, the voltage and power efficiency, and...
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Metrological analysis of precision of the system of delivering a water capsule for explosive production of water aerosol
PublicationIn this paper an analysis of precision of the system controlling delivery by a helicopter of water-capsule designed for extinguishing large scale fires is presented. The analysis was performed using the numerical method of distribution propagation (Monte Carlo method) supplemented with results of application of the uncertainty propagation method. In addition the optimum conditions for the airdrop are determined to ensure achievement...
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Detection of gaseous compounds with different techniques
PublicationSensing technology has been developed for detection of gases in some environmental, industrial, medical, and scientific applications. The main tasks of these works is to enhance performance of gas sensors taking into account their different applicability and scenarios of operation. This paper presents the descriptions, comparison and recent progress in some existing gas sensing technologies. Detailed introduction to optical sensing...
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Histogram of Oriented Gradients with Cell Average Brightness for Human Detection
PublicationA modification of the descriptor in a human detector using Histogram of Oriented Gradients (HOG) and Support Vector Machine (SVM) is presented. The proposed modification requires inserting the values of average cell brightness resulting in the increase of the descriptor length from 3780 to 3908 values, but it is easy to compute and instantly gives ≈ 25% improvement of the miss rate at 10‒4 False Positives Per Window (FPPW). The...
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A system for acoustic field measurement employing cartesian robot
PublicationA system setup for measurements of acoustic field, together with the results of 3D visualisations of acoustic energy flow are presented in the paper. Spatial sampling of the field is performed by a Cartesian robot. Automatization of the measurement process is achieved with the use of a specialized control system. The method is based on measuring the sound pressure (scalar) and particle velocity (vector) quantities. The aim of the...
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An Implementation of a Compact Smart Resistive Sensor Based on a Microcontroller with an Internal ADC
PublicationIn the paper a new implementation of a compact smart resistive sensor based on a microcontroller with internal ADCs is proposed and analysed. The solution is based only on a (already existing in the system) microcontroller and a simple sensor interface circuit working as a voltage divider consisting of a reference resistor and the resistive sensor connected in parallel with an interference suppression capacitor. The measurement...
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Programmable Input Mode Instrumentation Amplifier Using Multiple Output Current Conveyors
PublicationIn this paper a programmable input mode instrumentation amplifier (IA) utilising second generation, multiple output current conveyors and transmission gates is presented. Its main advantage is the ability to choose a voltage or current mode of inputs by setting the voltage of two configuration nodes. The presented IA is prepared as an integrated circuit block to be used alone or as a sub-block in a microcontroller or in a field...
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QUASI-DISTRIBUTED NETWORK OF LOW-COHERENCE FIBER-OPTIC FABRY-PÉROT SENSORS WITH CAVITY LENGTH-BASED ADDRESSING
PublicationDistributed measurement often relies on sensor networks. In this paper, we present the construction of low coherent fiber-optic Fabry-Pérot sensors connected into a quasi-distributed network. We discuss the mechanism of spectrum modulation in this type of sensor and the constraints of assembly of such sensors in the network. Particular attention was paid to separate the signals from individual sensors, which can be achieved by...
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Investigation of optical properties of Infitec and Active Stereo stereoscopic techniques for CAVE-type virtual reality systems
PublicationIn recent years, many scientific and industrial centres in the world developed virtual reality systems or laboratories. At present, among the most advanced virtual reality systems are CAVE-type (Cave Automatic Virtual Environment) installations. Such systems usually consist of four, five, or six projection screens arranged in the form of a closed or hemi-closed space. The basic task of such systems is to ensure the effect of user...
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Reduced-cost design closure of antennas by means of gradient search with restricted sensitivity update
PublicationDesign closure, i.e., adjustment of geometry parameters to boost the performance, is a challenging stage of antenna design process. Given complexity of contemporary structures, reliable parameter tuning requires numerical optimization and can be executed using local algorithms. Yet, EM-driven optimization is a computationally expensive endeavour and reducing its cost is highly desirable. In this paper, a modification of the trust-region...
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A design framework for rigorous constrained EM-driven optimization of miniaturized antennas with circular polarization
PublicationCompact radiators with circular polarization are important components of modern mobile communication systems. Their design is a challenging process which requires maintaining simultaneous control over several performance figures but also the structure size. In this work, a novel design framework for multi-stage constrained miniaturization of antennas with circular polarization is presented. The method involves sequential optimization...
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EVALUATION OF THE NO2CONCENTRATION PREDICTION POSSIBILITYBASED ON STATIC AND DYNAMIC RESPONSES OF TGS SENSORSAT CHANGING HUMIDITY LEVELS
PublicationThe commercially available metal-oxide TGS sensors are widely used in many applications due to thefact that they are inexpensive and considered to be reliable. However, they are partially selective and theirresponses are influenced by various factors,e.g. temperature or humidity level. Therefore, it is importanttodesign a proper analysis system of the sensor responses. In this paper, the results of examinations of eightcommercial...
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Exhaled breath analysis by resistive gas sensors
PublicationBreath analysis has attracted human beings for centuries. It was one of the simplest methods to detect various diseases by using human smell sense only. Advances in technology enable to use more reliable and standardized methods, based on different gas sensing systems. Breath analysis requires the detection of volatile organic compounds (VOCs) of the concentrations below individual ppm (parts per million). Therefore, advanced detection...
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EVALUATION OF LIQUID-GAS FLOW IN PIPELINE USING GAMMA-RAY ABSORPTION TECHNIQUE AND ADVANCED SIGNAL PROCESSING
PublicationLiquid-gas flows in pipelines appear in many industrial processes, e.g. in the nuclear, mining, and oil industry. The gamma-absorption technique is one of the methods that can be successfully applied to study such flows. This paper presents the use of thegamma-absorption method to determine the water-air flow parameters in a horizontal pipeline. Three flow types were studied in this work: plug, transitional plug-bubble,...