Search results for "Spectrogram"
showing 10 items of 34 documents
A Trajectory-Driven 3D Non-Stationary mm-Wave MIMO Channel Model for a Single Moving Point Scatterer
2021
This paper proposes a new non-stationary three-dimensional (3D) channel model for a physical millimeter wave (mm-Wave) multiple-input multiple-output (MIMO) channel. This MIMO channel model is driven by the trajectory of a moving point scatterer, which allows us to investigate the impact of a single moving point scatterer on the propagation characteristics in an indoor environment. Starting from the time-variant (TV) channel transfer function, the temporal behavior of the proposed non-stationary channel model has been analyzed by studying the TV micro-Doppler characteristics and the TV mean Doppler shift. The proposed channel model has been validated by measurements performed in an indoor e…
Acoustics of snoring and automatic snore sound detection in children
2017
Objective Acoustic analyses of snoring sounds have been used to objectively assess snoring and applied in various clinical problems for adult patients. Such studies require highly automatized tools to analyze the sound recordings of the whole night's sleep, in order to extract clinically relevant snore- related statistics. The existing techniques and software used for adults are not efficiently applicable to snoring sounds in children, basically because of different acoustic signal properties. In this paper, we present a broad range of acoustic characteristics of snoring sounds in children (N = 38) in comparison to adult (N = 30) patients. Approach Acoustic characteristics of the signals we…
Estimation of the Velocity of Multiple Moving Persons in Non-Stationary Indoor Environments from Received RF Signals
2019
This paper presents a new accurate iterative procedure to estimate the time-variant (TV) velocity, i.e., TV speed, TV vertical angle-of- motion (VAOM), and TV horizontal angle-of-motion (HAOM), of multiple moving objects/persons in three-dimensional (3D) non-stationary indoor propagation environments. The indoor space is assumed to be equipped with a distributed 3x3 multiple-input multiple-output (MIMO) system. The proposed procedure focuses on estimating the TV speed, TV VAOM, and TV HAOM by matching the spectrogram of the complex channel gain of a non- stationary indoor channel model to the spectrogram obtained from received radio frequency (RF) signals. Together with the velocity …
Exploring gravitational-wave detection and parameter inference using deep learning methods
2020
The data that support the findings of this study are openly available at the following URL/DOI: https://arxiv.org/abs/2011.10425.
Extremely low frequency band station for natural electromagnetic noise measurement
2015
A new permanent ELF measurement station has been deployed in Sierra Nevada, Spain. It is composed of two magnetometers, oriented NS and EW, respectively. At 10 Hz, their sensitivity is 19 μV/pT and the signal-to-noise ratio (SNR) is 28 dB for a time-varying signal of 1 pT, the expected field amplitude in Sierra Nevada. The station operates for frequencies below 24 Hz. The magnetometers, together with their corresponding electronics, have been specifically designed to achieve such an SNR for small signals. They are based on high-resolution search coils with ferromagnetic core and 106 turns, operating in limited geometry configuration. Different system noise sources are considered, and a stud…
Spectrogram Analysis of Non-Stationary RSE-to-Car Channels Behaviour for Braking Situations
2017
Master's thesis Information- and communication technology IKT590 - University of Agder 2017 Car-to-car (C2C) and car-to-infrastructure (C2I) communications promise revolutionary improvements in transportation due to its possibilities to improve the road safety and tra c management. C2C is a system designed to exchange information between vehicles, and C2I is a communication model that allows vehicles to share information with the infrastructure such as roadside equipment (RSE). These communications are considered as essential elements of the intelligent transport system (ITS). In this regard, reliability of the communication is vital to provide warning of an impending accident. Thus, the an…
Gravitational-wave parameter inference using Deep Learning
2021
We explore machine learning methods to detect gravitational waves (GW) from binary black hole (BBH) mergers using deep learning (DL) algorithms. The DL networks are trained with gravitational waveforms obtained from BBH mergers with component masses randomly sampled in the range from 5 to 100 solar masses and luminosity distances from 100 Mpc to, at least, 2000 Mpc. The GW signal waveforms are injected in public data from the O2 run of the Advanced LIGO and Advanced Virgo detectors, in time windows that do not coincide with those of known detected signals, and the data from each detector in the Advanced LIGO and Advanced Virgo network is combined into a unique RGB image. We show that a clas…
Collective Reasoning over Shared Concepts for the Linguistic Atlas of Sicily
2013
In this chapter, collective intelligence principles are applied in the context of the Linguistic Atlas of Sicily (ALS - Atlante Linguistico Siciliano), an interdisciplinary research focusing on the study of the Italian language as it is spoken in Sicily, and its correlation with the Sicilian dialect and other regional varieties spoken in Sicily. The project has been developed over the past two decades and includes a complex information system supporting linguistic research; recently it has grown to allow research scientists to cooperate in an integrated environment to produce significant scientific advances in the field of ethnologic and sociolinguistic research. An interoperable infrastruc…
Patskaņu izrunas īpatnības skotu angļu valodā (korpusā SCOTS)
2018
Skotijas vēsture un pašreizējie apstākļi ir multilingvāli un tur lietotā angļu valoda atšķiras no citur lietotajām angļu valodas paveidiem ar tās izrunas modeli. Šī darba mērķis ir patskaņu izpēte skotu standarta angļu valodā, lai raksturotu tās patskaņu sistēmu salīdzinājumā ar standarta britu angļu valodu un novērotu kādas iespējamās līdzības. Šī mērķa sasniegšanai izmantotā metode ir patskaņu formantu akustiskā kvantitatīvā analīze, kurai paraugi ņemti no Skotu Tekstu un Runas Korpusa (Scottish Corpus of Texts&Speech). Pētījuma rezultāti atklāj, ka skotu angļu valodas lietotājiem ir atšķirīgi patskaņu inventāri un patskaņu artikulācijas veids var atšķirties starp dažādām lietotāju grupām…
Motorcyclists Safety System to avoid Rear End Collisions based on Acoustic Signatures
2017
International audience; In many Asian countries, motorcyclists have a higher fatality rate as compared to other vehicles. Among many other factors, rear end collisions are also contributing for these fatalities. Collision detection systems can be useful to minimize these accidents. However, the designing of efficient and cost effective collision detection system for motorcyclist is still a major challenge. In this paper, an acoustic information based, cost effective and efficient collision detection system is proposed for motorcycle applications. The proposed technique uses the Short time Fourier Transform (STFT) to extract the features from the audio signal and Principal component analysis…