Filters
total: 1835
-
Catalog
- Publications 1443 available results
- Journals 19 available results
- Publishing Houses 1 available results
- People 15 available results
- Inventions 2 available results
- Projects 3 available results
- Laboratories 1 available results
- Research Equipment 1 available results
- e-Learning Courses 5 available results
- Events 2 available results
- Open Research Data 343 available results
displaying 1000 best results Help
Search results for: IMPULSE NOISE
-
Acoustic lifecycle study of the double-layer porous asphalt on E4 in Huskvarna, Sweden
PublicationIn 2010 a double-layer porous asphalt concrete (DPAC) pavement was constructed on the E4 motorway through the Swedish city Huskvarna. Earlier experience in Sweden indicated that it was feasible to obtain a high initial noise reduction but due to the widespread use of studded tires in winter, clogging and ravelling created losses of around 2 dB per year, with an expected acoustical lifetime of only 3 years. However, the improved...
-
On noncausal identification of nonstationary stochastic systems
PublicationIn this paper we consider the problem of noncausal identification of nonstationary,linear stochastic systems, i.e., identification based on prerecorded input/output data. We show how several competing weighted least squares parameter smoothers, differing in memory settings, can be combined together to yield a better and more reliable smoothing algorithm. The resulting parallel estimation scheme automatically adjusts its smoothing...
-
Poroelastic Material for Urban Roads Wearing Courses
PublicationConventional road materials used for producing wearing courses of roads are based on mineral aggregate and bituminous or Portland cement binders. The road materials must be optimized for different properties, including skid resistance, durability, rolling resistance and tire/road noise. Unfortunately, it seems that within classic technologies it is very difficult to achieve further reduction of tire/road noise. Innovative porous...
-
Poroelastic Material for Urban Roads Wearing Courses
PublicationConventional road materials used for producing wearing courses of roads are based on mineral aggregate and bituminous or Portland cement binders. The road materials must be optimized for different properties, including skid resistance, durability, rolling resistance and tire/road noise. Unfortunately, it seems that within classic technologies it is very difficult to achieve further reduction of tire/road noise. Innovative porous...
-
Acoustics - new services for urban planning, research and education
PublicationThe main purpose of the presented design is twofold, namely: providing detailed information about the noise threats that occur every day in city areas and preventing the noise induced hearing loss especially among young people. An experimental system designed for the continuous monitoring of the acoustic climate of urban areas was developed and implemented within the PLGrid Plus project. The assessment of environmental threats...
-
APPLICATION OF STATISTICAL FEATURES AND MULTILAYER NEURAL NETWORK TO AUTOMATIC DIAGNOSIS OF ARRHYTHMIA BY ECG SIGNALS
PublicationAbnormal electrical activity of heart can produce a cardiac arrhythmia. The electrocardiogram (ECG) is a non-invasive technique which is used as a diagnostic tool for cardiac diseases. Non-stationarity and irregu- larity of heartbeat signal imposes many difficulties to clinicians (e.g., in the case of myocardial infarction arrhythmia). Fortunately, signal processing algorithms can expose hidden information within ECG signal contaminated...
-
MICROSEISMIC EVENT DETECTION USING DIFFERENT ALGORITHMS ON REAL DATA FROM PATCH ARRAY GEOPHONE GRID FROM EASTERN POMERANIA FRACTURING JOB
PublicationThe microseismic monitoring is a method of monitoring of fracture propagation during hydraulic fracturing process. Hydraulic fracturing is a method of reservoir stimulation used especially for unconventional gas recovery. A matrix of several thousand geophones is placed on the surface of earth to record every little tremor of ground induced by fracturing process. Afterwards, the signal is analysed and the place of tremor occurrence...
-
Electron mobility variance in semiconductors: the variance approach
PublicationPraca przedstawia nowe podejście da analizy zjawisk losowych w półprzewodnikach. Uwzględnia kilka mechanizmów zjawisk fluktuacji ruchliwości w półprzewodnikach, prowadzących do powstawamai składowej szumów typu 1/f, dominujących w zakresie małych czetotliwości. Przedstawia analizę sposobu wyznaczenia stałej Hooge'a określającej intensywność szumów typu 1/f.The statistical non-triviality of current carrier mobility fluctuations...
-
Metody usuwania zakłóceń podczas pomiarów polowych widm Ramana
PublicationW pracy zostały scharakteryzowane źródła zakłóceń występujące podczas pomiarów widm Ramana w warunkach polowych oraz sposoby redukcji ich wpływu na jakość rejestrowanych widm. Zaprezentowano wpływ czasu integracji na jakość rejestrowanych widm w przypadkach, gdy szumy własne spektrometru mają składową typu 1/f, dominującą w zakresie małych częstotliwości. Przedstawiono także wyniki uzyskane podczas pomiarów z detekcją synchroniczną,...
-
Optimum Choice of Randomly Oriented Carbon Nanotube Networks for UV-Assisted Gas Sensing Applications
PublicationWe investigated the noise and photoresponse characteristics of various optical transparencies of nanotube networks to identify an optimal randomly oriented network of carbon nanotube (CNT)-based devices for UV-assisted gas sensing applications. Our investigation reveals that all of the studied devices demonstrate negative photoconductivity upon exposure to UV light. Our studies confirm the effect of UV irradiation on the electrical...
-
Low frequency noise measurements in advanced silocon devices.**2003, 136 s.116 rys. bibliogr. 29 poz. maszyn. Pomiary małoczęstotliwościowych szumów zaawansowanych elementów krzemowych. Rozprawa doktorska /15.04.2003./ Inst. Natl. P. Grenoble Promotorzy: prof. dr hab. inż. L. Spiralski, dr CNRS G. Ghibaudo.
PublicationW pracy przedstawiono automatyczny system do pomiarów małoczęstotliwoscio-wych szumów struktur elementów półprzewodnikowych. System umożliwia automa-tyczne wyznaczanie charakterystyk stałoprądowych badanego elementu, pomiarszumów i wyznaczanie gęstości widmowej mocy w zadanym zakresie polaryzacji.Przytoczono wyniki przeprowadzonych testów systemu. Ważną składową pracy wy-niki pomiarów szumów tranzystorów MOS i bipolarnych...
-
Applications of Raman spectroscopy for detection of selected substances in tissues
PublicationThis dissertation explores the applications of Raman spectroscopy for biological tissue analysis. Basics of Raman and surface-enhanced Raman spectroscopy (SERS) are described, along with an analysis of the literature on biodetection and non-invasive blood analysis with emphasis on glucose detection. Instrumentation for Raman measurements is described. The sources of noise and interferences occurring in biological tissue measurements...
-
User Orientation Detection in Relation to Antenna Geometry in Ultra-Wideband Wireless Body Area Networks Using Deep Learning
PublicationIn this paper, the issue of detecting a user’s position in relation to the antenna geometry in ultra-wideband (UWB) off-body wireless body area network (WBAN) communication using deep learning methods is presented. To measure the impulse response of the channel, a measurement stand consisting of EVB1000 devices and DW1000 radio modules was developed and indoor static measurement scenarios were performed. It was proven that for...
-
Analytical fluctuation enhanced sensing by resistive gas sensors
PublicationResistance fluctuations across polarised resistive gas sensors were studied in detail to evaluate sensor working conditions for detecting methane and ammonia at various concentrations. The 1/f noise component typically dominates other noise sources up to a few kHz and can be utilised to improve gas selectivity when compared with measurements of the sensor DC resistance. The Arrhenius plot was created and the activation energy for...
-
The vortex flow caused by sound in a bubbly liquid
PublicationGeneration of vorticity in the field of intense sound in a bubbly liquid in the free half-space is considered. The reasons for generation of vorticity are nonlinearity, diffraction, and dispersion. Acoustic streaming differs from that in a Newtonian fluid. Under some conditions, the vortex flow changes its direction. Conclusions concern streaming induced by a harmonic or an impulse Gaussian beam.
-
A BRIEF REVIEW AND COMPARISON OF SELECTED EXPERIMENTAL METHODS FOR MEASURING NATURAL FREQUENCIES OF CIRCULAR SAW BLADES
PublicationDifferent methods for the empirical determination of the natural frequencies of circular saw blades are presented. Stationary methods, such as the harmonic and impulse tests, are discussed and the results of related comparison are given. The comparison of the methods revealed their degree of practical usefulness and their accuracy in determining natural frequencies. A combination of specific methods is proposed, which should allow...
-
Advanced operating methods
PublicationSelected operating methods of resistive gas sensors were presented. The methods utilize flicker noise (1/f noise), which gives additional information about ambient gas when compared with the recorded changes of DC resistance only. Methods of flicker noise measurements were outlined. Recently developed prototype gas sensors comprising golden nanoparticle functionalized with organic ligands can generate intense flicker noise induced...
-
Simulation of the weight averaging of pulse frequency modulated sensor output signal
Open Research DataThe aim of the research is investigation of the efficiency of weight averaging of pulse frequency modulated signal. It was shown that from the point of view of the reduction of the sampling error the best are polynomial weighing functions, for which the maximum of this component error decreases proportionally to the appropriate power of the number of...
-
Analog fault signature based on sigma-delta modulation and oscillation-test methodology.
PublicationW artykule dokonano przeglądu prac z zakresu testowania układów elektronicznych metodą oscylacyjną. Wskazując na niedostatki aktualnie stosowanej techniki testowania oscylacyjnego zaproponowano nową sygnaturę uszkodzeń dla układów analogowych. Proponowany parametr diagnostyczny jest wydobywany z odpowiedzi czasowej oscylatora testującego, w układzie złożonym z detektora szczytowego, modulatora sigma-delta oraz licznika rewersyjnego....
-
Efficiency of gas detection algorithms using fluctuation enhanced sensing
PublicationEfficiency of various gas detection algorithms by applying fluctuation enhanced sensing method was discussed. We have analyzed resistance noise observed in resistive WO3- nanowires gas sensing layers. Power spectral densities of the recorded noise were used as the input data vectors for two algorithms: the principal component analysis (PCA) and the support vector machine (SVM). The data were used to determine gas concentration...
-
Selected problems of high-power sonar sources
PublicationSpecyfika pracy współczesnych sonarów aktywnych wymaga cyklicznego wypełnienia energią szerokiego sektora sondowania. W przypadku użycia płaskich anten nadawczych oznacza to zwykle konieczność skupienia energii akustycznego impulsu nadawczego na stosunkowo małej powierzchni czynnej przetwornika elektroakustycznego (kluczowe znaczenie odgrywa tu częstotliwość pracy systemu). Zjawiska towarzyszące dużym poziomom źródła mogą powodować...
-
Lech Bałachowski prof. dr hab. inż.
People -
Application of PL-Grid Platform for Modeling of the Selected Acoustic Phenomena
PublicationDomain grids are specific computational environments, developed within the PLGrid Plus project. For the Acoustic domain grid two supercomputer grid based services were prepared. Dedicated software consists of the outdoor sound propagation module and psychoacoustical noise dosimeter. The results are presented in a form of maps of sound level and Temporary Threshold Shift (TTS) values, therefore the services may play an informative...
-
Identification of hydroacoustic wave sources of ship in motion
PublicationThis paper deals with results of identification tests of acoustic field spectrum of underwater noise generated by ship in motion. The field is connected with acoustic activity of ship mechanisms and devices in operation. Vibration energy generated by the mechanisms and devices is transferred through ship structural elements to surrounding water where it propagates in the form of acoustic waves of a broad band of frequencies. In...
-
Nonadditivity of quantum and classical capacities for entanglement breaking multiple-access channels and the butterfly network
PublicationWe analyze quantum network primitives which are entanglement breaking. We show superadditivity of quantum and classical capacity regions for quantum multiple-access channels and the quantum butterfly network. Since the effects are especially visible at high noise they suggest that quantum information effects may be particularly helpful in the case of the networks with occasional high noise rates. The present effects provide a qualitative...
-
Self-adjusting sub-sample delay estimator based on fractional delaying Hilbert transform filter
PublicationZaprezentowano nowe rozwiązanie samo-nastrajalnego estymatora opóźnienia sygnału sinusoidalnego, działającego w czasie dyskretnym. Zastosowano filtr Hilberta o skończonej odpowiedzi ipulsowej (FIR od ang. finite impulse response) zagregowany z filtrem ułamkowo-opóźniającym. Zilustrowano performancję estymatora, również w obecności szumu. Przeanalizowano jego złożoność numeryczną.
-
Pressure Pulsations in Turbine Blade Seal
PublicationThe paper presents the results of experimental investigations into pressure forces generated in a turbine labyrinth seal. The experiments were performed on a single-stage air model turbine of the impulse type. The performed experimental research proved that in a shroud clearance the pressure pulsates and the effects of the nozzle trailing edge thickness as well as the influence of the rotor blades are observed. The exemplary results...
-
Dynamical description of quantum computing: generic nonlocality of quantumnoise
PublicationWe develop a dynamical non-Markovian description of quantum computing in the weak-coupling limit, in the lowest-order approximation. We show that the long-range memory of the quantum reservoir (such as the 1/t4 one exhibited by electromagnetic vacuum) produces a strong interrelation between the structure of noise and the quantum algorithm, implying nonlocal attacks of noise. This shows that the implicit assumption of quantum error...
-
Container Cargo Safety. New solutions and future trends
PublicationThe smoothness and flexibility of distribution of goods by containers are teh most important impulses for the development in these means of transport. But the second main reason for the growing containerization of freifht is cargo safety.
-
Formation of acoustic field in rooms
PublicationPaper describes known form literature method of sound diffusity index assesment, which utilizes impulse response of the room. Process of froming diffused sound field using this method was investigated.Increase of sound diffusity index in time was noted in rooms differing in shape,volume and reverberation time. Exponential growth of sound diffusion index was noted which correlates with other acoustical rooms measures.
-
A New Method of Noncausal Identification of Time-varying Systems
PublicationThe paper shows that the problem of noncausal identification of a time-varying FIR (finite impulse response) sys- tem can be reformulated, and solved, as a problem of smoothing of the preestimated parameter trajectories. Characteristics of the smoothing filter should be chosen so as to provide the best trade- off between the bias and variance of the resulting estimates. It is shown that optimization of the smoothing operation can...
-
Piotr Chrzan prof. dr hab. inż.
PeopleUrodził się w 1954 r. w Sopocie. Jest absolwentem Wydziału Elektroniki Politechniki Gdańskiej (1978). W 1980 r. podjął pracę na Wydziale Elektrycznym w zespole prof. Jerzego Jaczewskiego. W 1988 r. uzyskał stopień naukowy doktora nauk technicznych, habilitację w 1999 r., w zakresie elektrotechniki: energoelektroniki i automatyki napędu, a tytuł profesora w 2017 r. Był promotorem 6 obronionych prac doktorskich (w tym 3 z wyróżnieniem)....
-
Impedance spectra of RC model as a result of testing pulse excitation measurement method
Open Research DataThe impedance spectrum of RC model object obtained using pulse excitation EIS impedance spectrosocpy measurement method. The 1V voltage pulse excitation duration was set to 0.1s and the total acqusition time was set to 1000s. The object under test was built using RC components connected as Baunier model of anticorrosion coating with the following components...
-
PULSE and ECG measurement from the hand with elbows in the air - Woman 27 age
Open Research DataThe data set presents the measurements of the pulse and the ECG signal from the hand made with the use of a proprietary measuring system based on the AD8232 chip, a set of green diode and a phototransistor made on the STM32 microcontroller. Thanks to such a constructed device, it is possible to measure the ECG signal in a non-standard way - from the...
-
PULSE and ECG measurement from the hand with elbows in the air - Man 29 age
Open Research DataThe data set presents the measurements of the pulse and the ECG signal from the hand made with the use of a proprietary measuring system based on the AD8232 chip, a set of green diode and a phototransistor made on the STM32 microcontroller. Thanks to such a constructed device, it is possible to measure the ECG signal in a non-standard way - from the...
-
PULSE and ECG measurement from the hand with elbows to the body - Woman 27 age
Open Research DataThe data set presents the measurements of the pulse and the ECG signal from the hand made with the use of a proprietary measuring system based on the AD8232 chip, a set of green diode and a phototransistor made on the STM32 microcontroller. Thanks to such a constructed device, it is possible to measure the ECG signal in a non-standard way - from the...
-
PULSE and ECG measurement from the hand with elbows to the body - Man 29 age
Open Research DataThe data set presents the measurements of the pulse and the ECG signal from the hand made with the use of a proprietary measuring system based on the AD8232 chip, a set of green diode and a phototransistor made on the STM32 microcontroller. Thanks to such a constructed device, it is possible to measure the ECG signal in a non-standard way - from the...
-
PULSE and ECG measurement from the hand with elbows to the body - Woman 28 age
Open Research DataThe data set presents the measurements of the pulse and the ECG signal from the hand made with the use of a proprietary measuring system based on the AD8232 chip, a set of green diode and a phototransistor made on the STM32 microcontroller. Thanks to such a constructed device, it is possible to measure the ECG signal in a non-standard way - from the...
-
PULSE and ECG measurement from the hand with elbows in the air - Woman 28 age
Open Research DataThe data set presents the measurements of the pulse and the ECG signal from the hand made with the use of a proprietary measuring system based on the AD8232 chip, a set of green diode and a phototransistor made on the STM32 microcontroller. Thanks to such a constructed device, it is possible to measure the ECG signal in a non-standard way - from the...
-
PULSE and ECG measurement from the hand with elbows to the body - Woman 24 age
Open Research DataThe data set presents the measurements of the pulse and the ECG signal from the hand made with the use of a proprietary measuring system based on the AD8232 chip, a set of green diode and a phototransistor made on the STM32 microcontroller. Thanks to such a constructed device, it is possible to measure the ECG signal in a non-standard way - from the...
-
PULSE and ECG measurement from the hand with elbows in the air - Man 53 age
Open Research DataThe data set presents the measurements of the pulse and the ECG signal from the hand made with the use of a proprietary measuring system based on the AD8232 chip, a set of green diode and a phototransistor made on the STM32 microcontroller. Thanks to such a constructed device, it is possible to measure the ECG signal in a non-standard way - from the...
-
PULSE and ECG measurement from the hand with elbows to the body - Woman 30 age
Open Research DataThe data set presents the measurements of the pulse and the ECG signal from the hand made with the use of a proprietary measuring system based on the AD8232 chip, a set of green diode and a phototransistor made on the STM32 microcontroller. Thanks to such a constructed device, it is possible to measure the ECG signal in a non-standard way - from the...
-
PULSE and ECG measurement from the hand with elbows to the body - Man 30 age
Open Research DataThe data set presents the measurements of the pulse and the ECG signal from the hand made with the use of a proprietary measuring system based on the AD8232 chip, a set of green diode and a phototransistor made on the STM32 microcontroller. Thanks to such a constructed device, it is possible to measure the ECG signal in a non-standard way - from the...
-
PULSE and ECG measurement from the hand with elbows to the body - Man 53 age
Open Research DataThe data set presents the measurements of the pulse and the ECG signal from the hand made with the use of a proprietary measuring system based on the AD8232 chip, a set of green diode and a phototransistor made on the STM32 microcontroller. Thanks to such a constructed device, it is possible to measure the ECG signal in a non-standard way - from the...
-
PULSE and ECG measurement from the hand with elbows in the air - Man 30 age
Open Research DataThe data set presents the measurements of the pulse and the ECG signal from the hand made with the use of a proprietary measuring system based on the AD8232 chip, a set of green diode and a phototransistor made on the STM32 microcontroller. Thanks to such a constructed device, it is possible to measure the ECG signal in a non-standard way - from the...
-
PULSE and ECG measurement from the hand with elbows in the air - Woman 24 age
Open Research DataThe data set presents the measurements of the pulse and the ECG signal from the hand made with the use of a proprietary measuring system based on the AD8232 chip, a set of green diode and a phototransistor made on the STM32 microcontroller. Thanks to such a constructed device, it is possible to measure the ECG signal in a non-standard way - from the...
-
PULSE and ECG measurement from the hand with elbows in the air - Woman 30 age
Open Research DataThe data set presents the measurements of the pulse and the ECG signal from the hand made with the use of a proprietary measuring system based on the AD8232 chip, a set of green diode and a phototransistor made on the STM32 microcontroller. Thanks to such a constructed device, it is possible to measure the ECG signal in a non-standard way - from the...
-
Experimental investigation of the weight averaging of pulse frequency modulated sensor output signal
Open Research DataThe research aims to practically verify the results of theoretical analysis and simulations of the efficiency of weight averaging of pulse frequency modulated signal. For this purpose, a suitable test stand was built, and the control software in the LabVIEW environment was prepared. Then, a series of experiments were carried out to process and analyze...
-
Robustness in Compressed Neural Networks for Object Detection
PublicationModel compression techniques allow to significantly reduce the computational cost associated with data processing by deep neural networks with only a minor decrease in average accuracy. Simultaneously, reducing the model size may have a large effect on noisy cases or objects belonging to less frequent classes. It is a crucial problem from the perspective of the models' safety, especially for object detection in the autonomous driving...
-
Suppression of distortions in signals received from Doppler sensor for vehicle speed measurement
PublicationDoppler 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...