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1

Research on vibration-based early diagnostic system for excavator motor bearing using 1-D CNN

Yandagsuren Dorjsuren, Kurauchi Tatsuki, Toriya Hisatoshi, Ikeda Hajime, Adachi Tsuyoshi, Kawamura Youhei

Journal of Sustainable Mining

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2023

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Vol. 22, iss. 1

65--80

EN

In mining, super-large machines such as rope excavators are used to perform the main mining operations. A rope excavator is equipped with motors that drive mechanisms. Motors are easily damaged as a result of harsh mining conditions. Bearings are important parts in a motor; bearing failure accounts for approximately half of all motor failures. Failure reduces work efficiency and increases maintenance costs. In practice, reactive, preventive, and predictive maintenance are used to minimize failures. Predictive maintenance can prevent failures and is more effective than other maintenance. For effective predictive maintenance, a good diagnosis is required to accurately determine motor-bearing health. In this study, vibration-based diagnosis and a one-dimensional convolutional neural network (1-D CNN) were used to evaluate bearing deterioration levels. The system allows for early diagnosis of bearing failures. Normal and failure-bearing vibrations were measured. Spectral and wavelet analyses were performed to determine the normal and failure vibration features. The measured signals were used to generate new data to represent bearing deterioration in increments of 10%. A reliable diagnosis system was proposed. The proposed system could determine bearing health deterioration at eleven levels with considerable accuracy. Moreover, a new data mixing method was applied.

2

Challenges in assessing the vibrations influence on people in buildings using non-contact measurements

Bróż Natalia, Nazarko Piotr

Czasopismo Inżynierii Lądowej, Środowiska i Architektury / Journal of Civil Engineering, Environment and Architecture

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2023

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Vol. 70

51--64

EN

This research article presents a comparative analysis of vibration assessments in lecture halls to investigate their influence on people using contact (accelerometers) and non-contact (laser vibrometers) measurement techniques. The study aims to verify the accuracy and reliability of vibration analysis in relation to two approaches and determined physical parameters, i.e. acceleration amplitudes and vibration velocities. The intriguing fact was that none of the building users reported any perceived discomfort from vibrations, despite the determined parameters of the signal measured using a laser vibrometer indicating exceedance of permissible vibration amplitudes in several frequency bands. The conducted comparative analysis leads to the conclusion that the location of the laser head tripod on the vibrating floor introduces significant vibration amplification, which in turn may lead to an incorrect assessment of the impact of vibrations on people in buildings. The studies described in the article were carried out in accordance with the procedure contained in the Polish national standard PN-B-02171. The obtained results and the resulting conclusions are an important contribution to a better understanding of the advantages and limitations resulting from the use of non-contact measurements.

3

The concept of disrupting anti-radiation missiles in a radar decoy

Ślesicka Anna, Ślesicki Błażej

Aviation and Security Issues

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2023

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No. 1

167--181

EN

The ongoing armed conflicts in the world today demonstrate the huge role of electronic reconnaissance, which is becoming one of the primary sources of data on the enemy and the area of operations. One of the tools of radioelectronic warfare, which includes electronic reconnaissance, are radiolocation stations, which play a key role in detecting, tracking and identifying enemy aircraft and in directing armaments to combat these threats. The enemy’s own radiolocation stations are also targeted. The missiles used to do this are called anti-radar missiles (ARM). One way to defend against them is to modify the electromagnetic field around the protected radar. The purpose of this article was to present a model of coherent interference of an anti-radiation missile in a radar trap system The authors applied an analysis of the available literature and carried out computer simulations in the MATLAB environment. In conclusion, the important role played by radar decoys on today’s battlefield was pointed out.

PL

Toczące się obecnie na świecie konflikty zbrojne dowodzą ogromnej roli rozpoznania elektronicznego, które staje się jednym z podstawowych źródeł danych na temat przeciwnika i obszaru działań. Jednym z narzędzi walki radioelektronicznej, w której skład wchodzi rozpoznanie elektroniczne, są stacje radiolokacyjne, pełniące kluczową rolę w wykrywaniu, śledzeniu i identyfikacji przeciwników latających oraz w kierowaniu uzbrojeniem w celu zwalczania tych zagrożeń. Własne stacje radiolokacyjne są również celem przeciwnika. Pociski, które do tego służą, nazywa się pociskami przeciwradiolokacyjnymi. Jednym ze sposobów obrony jest modyfikacja pola elektromagnetycznego w otoczeniu chronionego radaru. Celem artykułu było przedstawienie modelu koherentnego zakłócenia pocisku przeciwradiolokacyjnego w systemie pułapek radiolokacyjnych radaru. Autorzy zastosowali analizę dostępnej literatury oraz przeprowadzili symulacje komputerowe w środowisku Matlab. Podsumowując, wskazano na istotną rolę, jaką pełnią na dzisiejszym polu walki pułapki radiolokacyjne.

4

Detection and diagnosis of bearing defects using vibration signal processing

Bouaouiche Karim, Menasria Yamina, Khalfa Dalila

Archive of Mechanical Engineering

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2023

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LXX, nr 3

433--452

EN

This work presents an analysis of vibration signals for bearing defects using a proposed approach that includes several methods of signal processing. The goal of the approach is to efficiently divide the signal into two distinct components: a meticulously organized segment that contains relatively straightforward information, and an inherently disorganized segment that contains a wealth of intricately complex data. The separation of the two component is achieved by utilizing the weighted entropy index (WEI) and the SVMD algorithm. Information about the defects was extracted from the envelope spectrum of the ordered and disordered parts of the vibration signal. Upon applying the proposed approach to the bearing fault signals available in the Paderborn university database, a high amplitude peak can be observed in the outer ring fault frequency (45.9 Hz). Likewise, for the signals available in XJTU-SY, a peak is observed at the fault frequency (108.6 Hz).

5

Budowa liczników energii elektrycznej prądu przemiennego

Makles Piotr

Wiadomości Elektrotechniczne

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2022

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R. 90, nr 4

21--28

PL

W artykule przedstawiono rozwiązania konstrukcyjne stosowane w nowoczesnych, elektronicznych licznikach energii elektrycznej. Opisana została budowa podstawowych układów elektronicznych, ze szczególnym uwzględnieniem obwodów pomiarowych wpływających na dokładność oraz możliwości pomiarowe liczników. Zaprezentowane zostały również najważniejsze wymagania norm dotyczące niezawodności oraz bezpieczeństwa urządzeń.

EN

This article presents information about electricity meters construction. Measurement circuits of meters and informations about different circuits solutions accuracy has been presented. The most important requirements of standards regarding the safety and accuracy of electricity meters were also described.

6

Leaky partial updates to control a real device casing

Bismor Dariusz

Vibrations in Physical Systems

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2022

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Vol. 33, nr 3

art. no. 2022304

EN

Structural active noise control (ANC) is one of few solutions applicable when global noise reduction is required: control of a whole device casing allows to lower the acoustic energy emitted by this device. Unfortunately, structural ANC usually requires a large number of sensors and actuators, making the control system multichannel with large dimensionality. This in turn presents a huge computational power demands. There are several ways to lower this demand, the partial updates being one of them. The goal of this paper is to show applicability of the leaky partial update LMS algorithms in structural ANC of a washing machine casing. The transfer functions of the numerous device paths were identified using a real washing machine in the ANC laboratory. The identified transfer functions allowed to create a simulation system, where different algorithms could be easily tested. The results of the simulations confirm effectiveness of the proposed solution.

7

Enhancing speech signals based on an mems microphone array and temporal differences in the incoming signal

Felcyn Jan, Raszewski Michał

Vibrations in Physical Systems

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2022

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Vol. 33, nr 2

art. no. 2022202

EN

The development of the Internet of things and automatisation in everyday life also influences our houses. There are more and more devices on the market which can be controlled remotely. One kind of such control involves the use of voice signals. This method tends to use microphone arrays and dedicated algorithms to enhance the speech signal and recognize the words in it. In this project, a small 5-microphone array was developed. To enhance the quality of the signal, dedicated software was written. It consists of several modules, including the direction of arrival estimation, denoising, and differentiation between adults and children. The results showed that the custom algorithm can increase the signal to noise ratio by up to 6 dB.

8

Effect of changing body position on selected voice parameters

Węglarz Karolina, Wszołek Wiesław, Hemmerling Daria

Vibrations in Physical Systems

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2022

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Vol. 33, nr 3

art. no. 2022320

EN

Correct posture is a key element in the proper functioning of the entire body. Both defects and postural disorders lead to overload syndromes and degenerative changes in the musculoskeletal system. Different body positions correlate with respiratory parameters, which form the basis in modifying loudness and accentuation when speaking or singing Body posture can affect the quality of the voice signal and its fatigue. As movement and duration intensify, vocal effort increases. What is still open, however, is the problem of speech signal evaluation, especially in order to obtain assessments useful in the context of supporting medical diagnosis, optimizing therapy and monitoring rehabilitation. Meanwhile, such evaluations are what we need in medicine, rehabilitation and sports. This paper presents excerpts from a study of the effects of changes in posture and fatigue in healthy subjects, and those with phonation disorders, on changes in the acoustic parameters of the speech signal.

9

Application of the discrete linear chirp transform (DLCT) to estimate the parameters of multicomponent LFM signals

Fiołka Jerzy

Przegląd Elektrotechniczny

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2022

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R. 98, nr 6

45--49

EN

This paper is focused on method to estimate the parameters of multicomponent linear frequency modulation (LFM) signals. These nonstationary signals, which are often referred to as ”chirp”, are encountered in many fields such as communication, vibration analysis, radar systems. The presented method, which is based on the discrete linear chirp transform (DLCT), permits the chirp parameters to be precisely estimated. Its high performance, which was proven by the simulation results, coupled with its simplicity, makes this method useful for many applications.

PL

W artykule przedstawiono metodę estymacji parametrów wieloskładnikowych sygnałów z liniową modulacją częstotliwości. Z tego typu sygnałami mamy do czynienia w takich dziedzinach jak telekomunikacja, analiza drgań, systemy radarowe. Przedstawiona metoda, bazująca na DLCT (ang. Discrete linear chirp transform), pozwala na oszacowanie parametrów wspomnianych sygnałów. Jej wysoka skuteczność, potwierdzona wynikami symulacji, w połączeniu z prostotą, czyni metodę użyteczną w wielu zastosowaniach.

10

Przetwarzanie sygnałów : nasz wkład w cyfrowy świat

Kulpa Krzysztof, Świercz Mirosław, Dąbrowski Adam, Samczyński Piotr, Augustyniak Piotr

Elektronika : konstrukcje, technologie, zastosowania

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2022

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Vol. 63, Nr 11

35--38

PL

Artykuł prezentuje historię i najważniejsze dokonania Oddziału Signal Processing Society Polskiej Sekcji IEEE oczami jego założyciela i kolejnych przewodniczących. Uwagę zwraca zarówno wszechstronność zastosowań przetwarzania sygnałów we współczesnej technice, członkostwo w Oddziale przedstawicieli najważniejszych ośrodków w Polsce oraz mnogość inicjatyw podejmowanych wspólnie w ramach Oddziału i adaptacja ich form do potrzeb środowiska branżowego.

EN

The article presents the history and the most important achievements of the Signal Processing Society Chapter of the IEEE Polish Section through the eyes of its founder and subsequent chairmen. Attention is drawn to the versatility of signal processing applications in modern technology, the membership of the representatives of the most important centers in Poland in the Chapter, and the multitude of initiatives undertaken jointly within the Chapter and the adaptation of their forms to the needs of the society of professionals.

11

Fault diagnosis of induction motors rotor using current signature with different signal processing techniques

Guezam Abdelhak, Bessedik Sid Ahmed, Djekidel Rabah

Diagnostyka

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2022

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Vol. 23, No. 2

art. no. 2022201

EN

The popularity of asynchronous machines, particularly squirrel cage machines, stems from their inexpensive production costs, resilience, and low maintenance requirements. Unfortunately, potential flaws in these devices might have a negative impact on the facility's profitability and service quality. As a result, diagnostic tools for detecting flaws in these types of devices must be developed. Asynchronous machine problems can be diagnosed using a variety of methods. Signal processing techniques based on extracting information from characteristic quantities of electrical machine operation can provide highly useful information about flaws. The purpose of this research is to develop efficient algorithms based on numerous signal processing approaches for correctly detecting asynchronous cage machine rotor defects (rotor bar ruptures).

12

Zastosowanie wielosensorowego systemu pomiarowego do monitorowania procesu skrawania – przypadek sekwencyjnych procesów toczenia i nagniatania

Bartoszuk Marian, Grzesik Wit, Chudy Roman

Mechanik

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2021

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R. 94, nr 1

6--12

EN

In this paper, the structure and operational functions of a measurement system, which was installed on a 3-axis CNC lathe for monitoring and optimization of the cutting process are presented. In general, the system records signals of the components of the resultant cutting force, acceleration signals (cutting vibrations) and EFM force signals generated for various machining conditions employed. As a result, the total power consumed was determined. The generated data were archived in the expert system which supports the optimization of the cutting process in terms of various optimization criteria including power/energy consumption.

PL

W artykule przedstawiono budowę i funkcje eksploatacyjne układu pomiarowego, który został zainstalowany na 3-osiowej tokarce CNC w celu monitorowania i optymalizacji procesu skrawania. System rejestruje sygnały składowych wypadkowej siły skrawania, sygnały przyspieszenia (drgania skrawania) oraz sygnały siły EFM generowane dla różnych zastosowanych warunków obróbki. W rezultacie określono całkowitą pobieraną moc. Wygenerowane dane zostały zarchiwizowane w systemie ekspertowym, który wspiera optymalizację procesu cięcia pod kątem różnych kryteriów optymalizacji, w tym poboru mocy / energii.

13

Diagnosis of air compressor condition using minimum redunduncy maximum relevance (MRMR) algorithim and distance metric based classification

Al-Bugharbee Hussein, Samaka Hatem, Zubaidi Salah L.

Diagnostyka

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2021

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Vol. 22, No. 4

25--32

EN

Finding a reliable machines condition monitoring technique has been attracted many researchers to avoid the sudden failure in machines and the unexpected consequences. This work proposes a fault diagnosis of air compressors using frequency-based features and distance metric-based classification. The analyzed experimental datasets contain one healthy condition and seven different fault conditions. Features are extracted from the frequency spectrum, then the best feature sets are selected using MRMR algorithm and eventually the classification is conducted using a distance metric classifier. The results demonstrated the automatic classification with more than 97% correct classification rate. The effect of selected feature set size, training sample size on the classification accuracy is also investigated. From the results, this method of analysis can be used for early detection of faults with very great accuracy.

14

Using BCI and EEG to process and analyze driver’s brain activity signals during VR simulation

Nader Mirosław, Jacyna-Gołda Ilona, Nader Stanisław, Nehring Karol

Archives of Transport

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2021

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Vol. 60, iss. 4

137--153

EN

The use of popular brain–computer interfaces (BCI) to analyze signals and the behavior of brain activity is a very current problem that is often undertaken in various aspects by many researchers. This comparison turns out to be particularly useful when studying the flows of information and signals in the human-machine-environment system, especially in the field of transportation sciences. This article presents the results of a pilot study of driver behavior with the use of a pro-prietary simulator based on Virtual Reality technology. The study uses the technology of studying signals emitted by the human mind and its specific zones in response to given environmental factors. A solution based on virtual reality with the limitation of external stimuli emitted by the real world was proposed, and computational analysis of the obtained data was performed. The research focused on traffic situations and how they affect the subject. The test was attended by representatives of various age groups, both with and without a driving license. This study presents an original functional model of a research stand in VR technology that we designed and built. Testing in VR conditions allows to limit the influence of undesirable external stimuli that may distort the results of readings. At the same time, it increases the range of road events that can be simulated without generating any risk for the participant. In the presented studies, the BCI was used to assess the driver's behavior, which allows for the activity of selected brain waves of the examined person to be registered. Electro-encephalogram (EEG) was used to study the activity of brain and its response to stimuli coming from the Virtual Reality created environment. Electrical activity detection is possible thanks to the use of electrodes placed on the skin in selected areas of the skull. The structure of the proprietary test-stand for signal and information flow simulation tests, which allows for the selection of measured signals and the method of parameter recording, is presented. An important part of this study is the presentation of the results of pilot studies obtained in the course of real research on the behavior of a car driver.

15

Vibroacoustic condition monitoring of the complex rotation system based on multilevel signal processing

Pazdrii Olha, Bouraou Nadiia

Vibrations in Physical Systems

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2020

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Vol. 31, nr 2

art. no. 2020224

EN

This work is devoted to further research and improvement of the vibroacoustic condition monitoring of complex rotation system during operation. The low-frequency vibration and acoustic noise in the range 0-10 kHz is used as diagnostic information. We propose to use Bispectrum (BS) Analysis at the first level of signal processing, and Fractal Analysis of BS contour images at the second level of signal processing for the diagnosis of small imbalance of rotation system. The experimental studies of forced vibrations of the physical model (PM) of the rotation system are carried out under steady-state and non-steady-state rotation excitations. The results of the BS Analysis of vibroacoustical signals, which are emitted by a rotating PM during different excitation modes, are processed in order to determine fractal box-counting dimension (Minkowski dimension). The research shows that a small imbalance can be efficiently detected by the proposed multilevel signal processing in all modes of PM operation.

16

Identification of plastic deformations in carbon steel elements using the filtered Barkhausen Noise signal

Dybała Jacek, Nadulicz Krzysztof

Vibrations in Physical Systems

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2020

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Vol. 31, nr 1

art. no. 2020106

EN

The paper presents new approach to processing the Barkhausen Noise signal in order to detect and identify plastic deformations in carbon steel. A new automatic method of Barkhausen effect signal filtration was investigated. Apart from a classical measurement of Barkhausen effect signal, for which the RMS value is assumed, the signal waveform factor was also used in analyzes. The developed approach to processing the Barkhausen Noise signal has made it possible to obtain more useful diagnostic data than those obtained from the raw signal.

17

Secured wired BPL voice transmission system

Debita Grzegorz, Falkowski-Gilski Przemysław, Habrych Marcin, Miedziński Bogdan, Wandzio Jan, Jedlikowski Przemysław

Scientific Journal of the Military University of Land Forces

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2020

|

Vol. 52, No. 4(198)

947--955

EN

Designing a secured voice transmission system is not a trivial task. Wired media, thanks to their reliability and resistance to mechanical damage, seem an ideal solution. The BPL (Broadband over Power Line) cable is resistant to electricity stoppage and partial damage of phase conductors, ensuring continuity of transmission in case of an emergency. It seems an appropriate tool for delivering critical data, mostly clear and understandable voice messages. This paper describes such a system that was designed and evaluated in real-time operating conditions. It involved a two-way transmission of speech samples in American English and Polish. The efficiency of the designed solution was evaluated in the subjective study on a group of 15 people.

PL

Opracowanie bezpiecznego systemu transmisji mowy nie jest trywialnym zadaniem. Media przewodowe, z uwagi na niezawodność i odporność na uszkodzenia mechaniczne, zdają się być idealnym rozwiązaniem. Kabel BPL (Broadband over Power Line) jest odporny na przerwy w dostawie prądu i częściowe uszkodzenie przewodników fazowych, zapewniając ciągłość transmisji w przypadku awarii. Wydaje się odpowiednim narzędziem do dostarczania istotnych danych, w szczególności wyraźnych i zrozumiałych komunikatów głosowych. Artykuł ten opisuje taki system, który został opracowany oraz zbadany w rzeczywistych warunkach pracy. Obejmował on dwukierunkową transmisję próbek mowy w języku angielskim (amerykańskim) oraz polskim. Skuteczność zaprojektowanego rozwiązania została oceniona w badaniu subiektywnym na grupie 15 osób.

18

Metoda korekcji sygnału muzycznego w zmiennych warunkach akustycznych

Hoffmann Piotr

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2020

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nr 7-8

378--381, CD

PL

W referacie przedstawiono koncepcję automatycznego systemu korekcji sygnału muzycznego, uwzględniającego akustykę pomieszczenia oraz odtwarzany gatunek muzyczny. Zaproponowany algorytm jest oparty na odpowiedzi częstotliwościowej pomieszczenia i na jej podstawie kompensuje warunki akustyczne otaczające źródło dźwięku. W referacie przedstawiono wyniki testów subiektywnych oceniających skuteczność proponowanego algorytmu w zależności od gatunku muzycznego oraz warunków akustycznych. Przeprowadzone testy subiektywne wykonano zgodnie z metodologią MUSHRA i AB. Łącznie w obu testach wzięło udział ponad 90 osób, a uzyskane w nich wyniki zostały poddane analizie istotności statystycznej za pomocą testu ANOVA.

EN

In the paper, a new method of automatic music signal correction, taking into account room acoustics and the music genre being played, is proposed. The proposed algorithm takes into account the room frequency response and, on its basis, compensates the acoustic conditions surrounding the listener. The paper presents the results of subjective tests evaluating the effectiveness of the proposed algorithm depending on the music genre and acoustic conditions. The subjective tests were performed according to MUSHRA and AB methodology. In total, more than 90 people took part in both tests, and the results were analyzed for statistical significance with the ANOVA test.

19

Dobór parametrów filtracji w cepstrum dla potrzeb poprawy jakości odbieranego sygnału

Czapiewska Agnieszka, Łuksza Andrzej, Studański Ryszard, Żak Andrzej

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

|

2020

|

nr 7-8

374--377, CD

PL

W referacie zaproponowano metodę eliminacji wpływu efektu wielodrogowości poprzez analizę i filtrację odbieranego sygnału w cepstrum. Analiza taka, pozwala na wykrycie istnienia repliki (echa) sygnału nadawanego oraz odfiltrowanie tej repliki, co poprawia jakość realizowanej transmisji sygnału. W referacie zaprezentowano wyniki badan symulacyjnych.

EN

In paper a method of multipath propagation effect reduction based on analysis in cepstrum is presented. In this method signal in cepstrum is analysed, the signal replicas (echo) are detected and filtered, what leads to transmission quality improvement. In paper simulation results are presented.

20

Frequency response of Norris gap derivatives and its prosperities for gas spectra analysis

Cięszczyk Sławomir

Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska

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2020

|

T. 10, nr 4

25--28

EN

The article deals with an analysis of the properties of Norris gap derivatives. It discusses issues related to determining information from optical spectra measured with spectrometers. Impulse responses of differentiating filters were introduced using both Norris and Savitzky-Golay methods.The amplitude-frequency responses of the first and second order Norris differentiating filters were compared. The length impact of both segment and gaps on the frequency characteristics of filters was compared.The processing of exemplary gas spectra using the discussed technique was subsequently presented. The effect of first and second order derivatives on the spectra of carbon monoxide rotational lines for low resolution measurementsis investigated. The Norris method of derivatives arevery simple to implement and the calculation of theirparameters does not require the use of advanced numerical methods.

PL

Artykuł przedstawia analizę właściwości pochodnych według metody Norrisa. Omówiono w nim zagadnienia związane z wyznaczaniem informacji z widm optycznych mierzonychspektrometrami. Przedstawiono odpowiedzi impulsowe filtrów różniczkujących zarówno metodą Norrisa jak też Savitzky-Golay. Porównano odpowiedzi amplitudowo-częstotliwościowefiltrów różniczkujących Norrisa pierwszego i drugiego rzędu. Porównano wpływ zarówno długości segmentów jak i rozstępu (luk) na charakterystyki częstotliwościowe filtrów. Kolejno zaprezentowano przetwarzanieprzykładowych widm gazu z wykorzystaniem omawianej techniki. Przedstawiono także wpływ pochodnych pierwszego i drugiego rzędu na widma linii rotacyjnych tlenku węgla dla pomiarów o małej rozdzielczości. Metoda pochodnych według Norrisa jest bardzo prosta w implementacji a obliczanie jej parametrów nie wymaga stosowania zaawanasowanych metod numerycznych.