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Search results for: NONSTATIONARY MULTIVARIATE SIGNALS
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MODALITY corpus - SPEAKER 27 - SEQUENCE S2
Open Research DataThe MODALITY corpus is one of the multimodal database of word recordings in English. It consists of over 30 hours of multimodal recordings. The database contains high-resolution, high-framerate stereoscopic video streams and audio signals obtained from a microphone array and a laptop microphone. The corpus can be employed to develop an AVSR system,...
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Measurements of ultrasonic bulk and guided wave propagation in additively manufactured cubes and plates obtained by ultrasonic pulse velocity analyzer and scanning laser vibrometry
Open Research DataThe DataSet contains the results of measurements of ultrasonic wave propagation in additively manufactured samples made of polylactic acid (PLA). Three types of raster angles in two consecutive layers were assumed: 0°/90° (#1), 45°/-45° (#2) and 90°/90° (#3) with respect to the x-axis. For each printing variants a cubic sample (#C1-3) with dimensions...
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Design considerations for compact microstrip resonant cells dedicated to efficient branch-line miniaturization
PublicationA conventional compact microstrip resonant cell (CMRC)has been thoroughly investigated to enhance its slow-wave properties and subsequently ensure an efficient miniaturization of a microstrip circuit. The geometry of a classic CMRC has been improved in terms of slowwave effect in two progressive steps: (i) a single-element topology has been replaced with a double-element one and (ii) a high-impedance section has been refined by...
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A low complexity double-talk detector based on the signal envelope
PublicationA new algorithm for double-talk detection, intended for use in the acoustic echo canceller for voice communication applications, is proposed. The communication system developed by the authors required the use of a double-talk detection algorithm with low complexity and good accuracy. The authors propose an approach to doubletalk detection based on the signal envelopes. For each of three signals: the far-end speech, the microphone...
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An new method of audio-visual correlation analysis
PublicationThis paper presents a new methodology of conducting the audio-visual correlation analysis employing the gaze tracking system. Interaction between two perceptual modalities, seeing and hearing, their interaction and mutual reinforcement in a complex relationship was a subject of many research studies. Earlier stage of the carried out experiments at the Multimedia Systems Department (MSD) showed that there exists a relationship between...
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Indirect adaptive controller based on a self-structuring fuzzy system for nonlinear modeling and control
PublicationIn this paper, a unified nonlinear modeling and control scheme is presented. A self-structuring Takagi-Sugeno (T-S) fuzzymodel is used to approximate the unknown nonlinear plant based on I/O data collected on-line. Both the structure and theparameters of the T-S fuzzy model are updated by an on-line clustering method and a recursive least squares estimation(RLSE) algorithm. The rules of the fuzzy model can be added, replaced or...
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Sea bottom structure investigation by means of acoustic methods
PublicationThe main aim of the paper is the result of experimental investigations of the seabed in the Gulf of Gdańsk arried out using parametric echosounder as a main measuring tool. Examination of the surface's upper layer of the seabed, especially is acoustic properties, reflecting most often transsmision and reflection properties of the incident elastic wave, could be a valuable material for determination of the stratification, and the...
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Application of passive acoustic radar to automatic localization, tracking and classification of sound sources
PublicationA concept, practical realization and applications of the passive acoustic radar to automatic localization, tracking and classification of sound sources were presented in the paper. The device consists of a new kind of multichannel miniature sound intensity sensors and a group of digital signal processing algorithms. Contrary to active radars, it does not emit the scanning beam but after receiving surrounding sounds it provides...
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Study on the applicability of the measurements of magnetoelastic properties for a nondestructive evaluation of thermally inducted microstructure changes in the P91 grade steel
PublicationThe paper presents the resuIts of the investigation of the influence of duration and temperature oftempering process on the magnetoacoustic properties of P91 tempered martensite ferritic steeI. Duringtempering of martensitic steels the dislocation density. which initially is very high. systematicallydecreases what is confirmed both by analysis of the width of X-ray diffraction peaks and hardnessmeasurements. Magnetic hysteresis...
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Local Conformation and Cocrystallization Phenomena in Renewable Diaminoisoidide-Based Polyamides Studied by FT-IR, Solid State NMR, and WAXD
PublicationBiobased polyamides synthesized from diaminoisoidide (DAII), 1,4-diaminobutane, and sebacic acid are investigated by FT-IR, 13C{1H} magic-angle spinning/cross-polarization (CP/MAS) NMR spectroscopy, and WAXD. Their molecular conformation and mobility undergo distinct changes as a function of temperature and diaminoisoidide content in the compositions. The presence of randomly distributed diaminoisoidide (DAII) in the polyamides...
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Damage detection in a bolted lap joint using guided waves
PublicationThe paper presents the experimental investigation of guided waves application to the condition assessment of prestressed bolted connections and a concept of new quantitative indicator. The main goal of the research was the analysis of the influence of the contact conditions changes to the characteristics of a propagating disturbance. The experimental tests were carried out for a single bolted lap joint. The excitation and acquisition...
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Subjective and Objective Quality Evaluation Study of BPL -PLC Wired Medium
PublicationThis paper presents results of research on the effectiveness of bi-directional voice transmission in a 6 kV mine cable network using BPL-PLC (Broadband over Power Line - Power Line Communication) technology. It concerns both emergency cable state (supply outage with cable shorted at both ends) and loaded with distorted current waveforms. The narrowband (0.5 MHz–15 MHz) and broadband (two different modes, frequency range of 3 MHz–7.5...
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The development of an underwater telephone for digital communication purposes
PublicationThe underwater telephone HTL-10 has been designed to provide voice and data communication between helicopter and submarines using acoustic waves. It works in a half-duplex mode and uses analogue power-efficient modulation in the form of a single side-band, suppressed carrier, in a wide range of frequencies. It generates the transmitted signal, and processes the received signals. It is implemented with the use of digital signal...
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A VISION-BASED UNMANNED AERIAL VEHICLE NAVIGATION METHOD
PublicationThe satellite navigation systems are the main position sources for unmanned aerial vehicles (UAVs). This fact limits the area of UAVs operation to the places where radio signals is visible for a satellite navigation system receiver, mounted on the vehicle-outdoor navigation. Closed spaced are unavailable for vehicles which navigation is based on global satellite navigation systems (GNSS). Miniature UAV (MiniUAV) is able to operate...
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An IoT-Based Computational Framework for Healthcare Monitoring in Mobile Environments
PublicationThe new Internet of Things paradigm allows for small devices with sensing, processing and communication capabilities to be designed, which enable the development of sensors, embedded devices and other ‘things’ ready to understand the environment. In this paper, a distributed framework based on the internet of things paradigm is proposed for monitoring human biomedical signals in activities involving physical exertion. The main...
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Underwater Acoustic Imaging of the Sea
PublicationAcoustic waves are a carrier of information mainly in environments where the use of other types of waves, for example electromagnetic waves, is limited. The term acoustical imaging is widely used in the ultrasonic engineering to imaging areas in which the acoustic waves propagate. In particular, ultrasound is widely used in the visualization of human organs - ultrasonography (Nowicki, 2010). Expanding the concept, acoustical imaging...
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A Simplistic Downlink Channel Estimation Method for NB-IoT
PublicationThis paper presents a downlink channel estimation method intended for a Narrowband Internet of Things (NB-IoT) access link. Due to its low computational complexity, this method is well suited for energy-efficient IoT devices, still providing acceptable reception quality in terms of signal-to-noise (SNR) performance. This paper describes the physical layer of NB-IoT within the scope of channel estimation, and also reviews existing...
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Multimodal analysis of traction forces and the temperature dynamics of living cells with a diamond-embedded substrate
PublicationCells and tissues are constantly exposed to chemical and physical signals that regulate physiological and pathological processes. This study explores the integration of two biophysical methods: traction force microscopy (TFM) and optically detected magnetic resonance (ODMR) to concurrently assess cellular traction forces and the local relative temperature. We present a novel elastic substrate with embedded nitrogen-vacancy microdiamonds...
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EMPIRICAL ASSESMENT OF THE MAIN DRIVING SYSTEM OF THE CIRCULAR SAWING MACHINE
PublicationThe producers of panel saws tend to improve sawing accuracy and minimise a level of vibrations, to increase their competitiveness at the market. Mechanical vibrations in the main saw driving system, which level depend on a plethora independent factors, may really affect sawing accuracy and general machine tool vibrations. The objective of the research was to explore vibrations signals of the main spindle system, and to extract...
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Non-Contact Monitoring of ECG in the Home Environment—Selecting Optimal Electrode Configuration
PublicationCapacitive electrocardiography (cECG) is most often used in wearable or embedded measurement systems. The latter is considered in the paper. An optimal electrocardiographic lead, as an individual feature, was determined based on model studies. It was defined as the possibly highest value of the R-wave amplitude measured on the back of the examined person. The lead configuration was also analyzed in terms of minimizing its susceptibility...
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Study on Speech Transmission under Varying QoS Parameters in a OFDM Communication System
PublicationAlthough there has been an outbreak of multiple multimedia platforms worldwide, speech communication is still the most essential and important type of service. With the spoken word we can exchange ideas, provide descriptive information, as well as aid to another person. As the amount of available bandwidth continues to shrink, researchers focus on novel types of transmission, based most often on multi-valued modulations, multiple...
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Unsupervised machine-learning classification of electrophysiologically active electrodes during human cognitive task performance
PublicationIdentification of active electrodes that record task-relevant neurophysiological activity is needed for clinical and industrial applications as well as for investigating brain functions. We developed an unsupervised, fully automated approach to classify active electrodes showing event-related intracranial EEG (iEEG) responses from 115 patients performing a free recall verbal memory task. Our approach employed new interpretable...
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Improved RSS-Based DoA Estimation Accuracy in Low-Profile ESPAR Antenna Using SVM Approach
PublicationIn this paper, we have shown how the overall performance of direction-of-arrival (DoA) estimation using lowprofile electronically steerable parasitic array radiator (ESPAR) antenna, which has been proposed for Internet of Things (IoT) applications, can significantly be improved when support vector machine (SVM) approach is applied. Because the SVM-based DoA estimation method used herein relies solely on received signal strength...
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Detection of Water on Road Surface with Acoustic Vector Sensor
PublicationThis paper presents a new approach to detecting the presence of water on a road surface, employing an acoustic vector sensor. The proposed method is based on sound intensity analysis in the frequency domain. Acoustic events, representing road vehicles, are detected in the sound intensity signals. The direction of the incoming sound is calculated for the individual spectral components of the intensity signal, and the components...
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Application of 3D- printed hydrogels in wound healing and regenerative medicine
PublicationHydrogels are three-dimensional polymer networks with hydrophilic properties. The modifiable properties of hydrogels and the structure resembling living tissue allow their versatile application. Therefore, increasing attention is focused on the use of hydrogels as bioinks for three-dimensional (3D) printing in tissue engineering. Bioprinting involves the fabrication of complex structures from several types of materials, cells,...
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Shallow-Water Acoustic Communications in Strong Multipath Propagation Conditions
PublicationA phenomenon that has a strong impact on signal transmission conditions in Underwater Acoustic Communication (UAC) systems is multipath propagation. As a result of multipath propagation, the transmitted signal undergoes time dispersion which results in inter-symbol interference observed on the receiving side. Time dispersion is large, especially in horizontal channels in shallow waters which significantly limits the transmission...
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The values of Permutation Entropy for individuals with Normal Sinus Rhythm
Open Research DataThe dataset consists of calculated values of entropy of 75 000 intervals between consecutive heartbeats (RR intervals) for 54 patients with normal sinus rhythm (NSR). The original data were taken from PhysioNet Normal Sinus Rhythm RR Interval Database (cf. Goldberger A., Amaral L., Glass L., Hausdorff J., Ivanov P.C., Mark R., Mietus J.E., Moody G.B.,...
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The values of Permutation Entropy for patients with Congestive Heart Failure
Open Research DataThe dataset consists of calculated values of entropy of 75 000 intervals between consecutive heartbeats (RR intervals) for 29 patients with congestive heart failure (CHF). The original data were taken from PhysioNet Congestive Heart Failure RR Interval Database (cf. Goldberger A., Amaral L., Glass L., Hausdorff J., Ivanov P.C., Mark R., Mietus J.E.,...
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Investigation of the thermal conductivity of λ gypsum using the hot wire method
Open Research DataAn experimental study was conducted to determine the thermal conductivity coefficient λ using the ‘hot wire’ method for a building material. Gypsum specimens measuring 400 x 60 x 50 mm were made for the experiment. Along the long axis of the model, an insulated resistance wire with a diameter of 0.2 mm was poured into the gypsum slurry in the centre...
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Stable indirect adaptive control based on discrete-time T-S fuzzy model
PublicationThis paper presents an indirect adaptive fuzzy control scheme for uncertain nonlinear asymptotically stable plants.A discrete-time T-S fuzzy input-output model is employed to approximate the unknown plant dynamics. The T-S fuzzy model is fed with its own states, which are indeed its past outputs, rather than the measurements from the plants. Entirely based on this model, a feedback linearization control law is designed by using...
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Stable indirect adaptive control based on discrete-time T-S fuzzy model
PublicationThis paper presents an indirect adaptive fuzzy control scheme for uncertain nonlinear asymptotically stable plants.A discrete-time T-S fuzzy input-output model is employed to approximate the unknown plant dynamics. The T-S fuzzy model is fed with its own states, which are indeed its past outputs, rather than the measurements from the plants. Entirely based on this model, a feedback linearization control law is designed by using...
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Time-Domain Description of Point-Source Acoustic Wavefields as a Useful Approach in Ultrasonic Techniques
PublicationIn traditional acoustics, field problems are usually treated in the frequency domain, broadband fields being reduced to superposition of harmonic spectrum components. However, this approach is inherently acausal and it is known that in case of arbitrary signals, the distribution-based, time-domain description can be more effective. The present paper is an attempt to expand the time-domain linear systems formalism onto space problems...
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Will NILM Technology Replace Multi-Meter Telemetry Systems for Monitoring Electricity Consumption?
PublicationThe estimation of electric power utilization, its baseload, and its heating, light, ventilation, and air-conditioning (HVAC) power component, which represents a very large portion of electricity usage in commercial facilities, are important for energy consumption controls and planning. Non-intrusive load monitoring (NILM) is the analytical method used to monitor the energy and disaggregate total electrical usage into appliance-related...
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Analysis of Impulse Responses Measured in Motion in a Towing Tank
PublicationThe growing interest in developing autonomous underwater vehicles (AUVs) and creating underwater sensor networks (USNs) has led to a need for communication tools in underwater environments. For obvious reasons, wireless means of communication are the most desirable. However, conducting research in real conditions is troublesome and costly. Moreover, as hydroacoustic propagation conditions change very significantly, even during...
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High frequency dynamics of an isotropic Timoshenko periodic beam by the use of the Time-domain Spectral Finite Element Method
PublicationIn this work results of numerical simulations and experimental measurements related to the high frequency dynamics of an aluminium Timoshenko periodic beam are presented. It was assumed by the authors that the source of beam structural periodicity comes from periodical alterations to its geometry due to the presence of appropriately arranged drill-holes. As a consequence of these alterations dynamic characteristics of the beam...
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Visualization of short-term heart period variability with network tools as a method for quantifying autonomic drive
PublicationWe argue that network methods are successful in detecting nonlinear properties in the dynamics of autonomic nocturnal regulation in short-term variability. Two modes of visualization of networks constructed from RR-increments are proposed. The first is based on the handling of a state space. The state space of RR-increments can be modified by a bin size used to code a signal and by the role of a given vertex as the representation...
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Low-Power Receivers for Wireless Capacitive Coupling Transmission in 3-D-Integrated Massively Parallel CMOS Imager
PublicationThe paper presents pixel receivers for massively parallel transmission of video signal between capacitive coupled integrated circuits (ICs). The receivers meet the key requirements for massively parallel transmission, namely low-power consumption below a single μW, small area of less than 205 μm2, high sensitivity better than 160 mV, and good immunity to crosstalk. The receivers were implemented and measured in a 3-D IC (two face-to-face...
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On the Consumption of Multimedia Content Using Mobile Devices: a Year to Year User Case Study
PublicationIn the early days, consumption of multimedia content related with audio signals was only possible in a stationary manner. The music player was located at home, with a necessary physical drive. An alternative way for an individual was to attend a live performance at a concert hall or host a private concert at home. To sum up, audio-visual effects were only reserved for a narrow group of recipients. Today, thanks to portable players,...
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Detection and Imaging of Debonding in Adhesive Joints of Concrete Beams Strengthened with Steel Plates Using Guided Waves and Weighted Root Mean Square
PublicationStrengthening of engineering structures is an important issue, especially for elements subjected to variable loads. In the case of concrete beams or slabs, one of the most popular approaches assumes mounting an external reinforcement in the form of steel or composite elements by structural adhesives. A significant disadvantage of adhesive joints is the lack of access to the adhesive film for visual condition assessment, thus, there...
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Time-domain description of point-source acoustic wavefields as a useful approach in ultrasonic techniques
PublicationIn traditional acoustics, field problems are usually treated in the frequency domain, broadband fields being reduced to superposition of harmonic spectrum components. However, this approach is inherently acausal and it is known that in case of arbitrary signals, the distribution-based, time-domain description can be more effective. The present paper is an attempt to expand the time-domain linear systems formalism onto space problems...
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Bioelectronic nose: Current status and perspectives
PublicationA characteristic feature of human and animal organs of smell is the ability to identify hundreds of thousands of odours. It is accompanied by particular smell sensations, which are a basic source of information about odour mixture. The main structural elements of biological smell systems are the olfactory receptors. Small differences in a structure of odorous molecules (odorants) can lead to significant change of odour, which is...
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Non-destructive inspection of ground anchors using guided wave propagation
PublicationThis paper deals with numerical and experimental investigations of specific problems of guided wave propagation in ground anchors. The research focuses on recognizing the phenomenon of the energy transfer between anchor components. Particular attention is paid to characteristic features of guided waves propagating in free and embedded parts of the tendon, at the interface between the tendon and the surrounding anchor body as well...
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Guided wave propagation in debonding detection in CFRP-reinforced steel plate-like structures
PublicationThe present study investigates the guided wave propagation in multilayered steel specimens reinforced with carbon fiber reinforced polymer (CFRP) through theoretical, numerical, and experimental means. The effectiveness of externally bonded reinforcement (EBR) relies heavily on the bonding quality between the CFRP and the substrate. Premature debonding, a prevalent and hazardous defect, can arise from suboptimal manufacturing processes,...
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Comparison of tuning procedures based on evolutionary algorithm for multi-region fuzzy-logic PID controller for non-linear plant
PublicationThe paper presents a comparison of tuning procedures for a multi-region fuzzy-logic controller used for nonlinear process control. This controller is composed of local PID controllers and fuzzy-logic mechanism that aggregates local control signals. Three off-line tuning procedures are presented. The first one focuses on separate tuning of local PID controllers gains in the case when the parameters of membership functions of fuzzy-logic...
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A simple modification of PCR thermal profile applied to evade persisting contamination
PublicationThe polymerase chain reaction (PCR), one of the most commonly applied methods of diagnostics and molecular biology has a frustrating downside known as the false positive signal or contamination. Several solutions to avoid and to eliminate PCR contaminations have been worked out to date but the implementation of these solutions to laboratory practice may be laborious and time consuming. A simple approach to circumvent the problem...
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Separability Assessment of Selected Types of Vehicle-Associated Noise
PublicationMusic Information Retrieval (MIR) area as well as development of speech and environmental information recognition techniques brought various tools in-tended for recognizing low-level features of acoustic signals based on a set of calculated parameters. In this study, the MIRtoolbox MATLAB tool, designed for music parameter extraction, is used to obtain a vector of parameters to check whether they are suitable for separation of...
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A concept of Signal Equalization Method Based on Music Genre and the Listener's Room Characteristics
PublicationA research study that investigates the influence of the room acoustics environment on the frequency characteristic of the audio signal playback is presented. First, a novel spectral equalization method of the room acoustic conditions is introduced. On the basis of the frequency response of the room, a system for room acoustics compensation based on eight-band equalizer is proposed. The system settings depend on music genre. In...
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Analysis of Impulse Responses Measured in Motion in a Towing Tank
PublicationThe growing interest in developing autonomous underwater vehicles (AUVs) and creating underwater sensor networks (USNs) has led to a need for communication tools in underwater environments. For obvious reasons, wireless means of communication are the most desirable. However, conducting research in real conditions is troublesome and costly. Moreover, as hydroacoustic propagation conditions change very significantly, even during...
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Broadening the scope of measurement and analysis of vibrations of an organ pipe employing intensity probe, simulations, and highspeed camera
PublicationThis paper shows an integrated approach to measure, analyze, and model phenomena occurring in an organ pipe driven by pressurized air. The aim of this paper is two-fold, i.e., to measure the pressure signal and the intensity field around the mouth by means of an intensity probe and to visualize and observe the motion of the air jet, which represents the excitation mechanism of the system. This is realized through two techniques,...
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Automatic Emotion Recognition in Children with Autism: A Systematic Literature Review
PublicationThe automatic emotion recognition domain brings new methods and technologies that might be used to enhance therapy of children with autism. The paper aims at the exploration of methods and tools used to recognize emotions in children. It presents a literature review study that was performed using a systematic approach and PRISMA methodology for reporting quantitative and qualitative results. Diverse observation channels and modalities...