scholarly journals Non-Contact Respiration Monitoring and Body Movements Detection for Sleep Using Thermal Imaging

Sensors ◽  
2020 ◽  
Vol 20 (21) ◽  
pp. 6307
Author(s):  
Prasara Jakkaew ◽  
Takao Onoye
Keyword(s):  
Region Of Interest ◽  
Processing Technique ◽  
The Body ◽  
Body Movements ◽  
Signal Processing Technique ◽  
Respiration Monitoring ◽  
Breathing Motion ◽  
Video Recordings ◽  
Temperature Detection ◽  
Roi Extraction

Monitoring of respiration and body movements during sleep is a part of screening sleep disorders related to health status. Nowadays, thermal-based methods are presented to monitor the sleeping person without any sensors attached to the body to protect privacy. A non-contact respiration monitoring based on thermal videos requires visible facial landmarks like nostril and mouth. The limitation of these techniques is the failure of face detection while sleeping with a fixed camera position. This study presents the non-contact respiration monitoring approach that does not require facial landmark visibility under the natural sleep environment, which implies an uncontrolled sleep posture, darkness, and subjects covered with a blanket. The automatic region of interest (ROI) extraction by temperature detection and breathing motion detection is based on image processing integrated to obtain the respiration signals. A signal processing technique was used to estimate respiration and body movements information from a sequence of thermal video. The proposed approach has been tested on 16 volunteers, for which video recordings were carried out by themselves. The participants were also asked to wear the Go Direct respiratory belt for capturing reference data. The result revealed that our proposed measuring respiratory rate obtains root mean square error (RMSE) of 1.82±0.75 bpm. The advantage of this approach lies in its simplicity and accessibility to serve users who require monitoring the respiration during sleep without direct contact by themselves.

Water skating in the larvae of dixella aestivalis (Diptera) and hydrobius fuscipes (Coleoptera)

1999 ◽  
Vol 202 (7) ◽  
pp. 845-853
Author(s):  
J. Brackenbury
Keyword(s):  
High Speed ◽  
The Body ◽  
Water Interface ◽  
Body Movements ◽  
Chironomid Larvae ◽  
High Speed Video ◽  
Adhesive Organ ◽  
Video Recordings ◽  
Air Water Interface

The kinematics of locomotion was investigated in the aquatic larvae of Dixella aestivalis and Hydrobius fuscipes with the aid of high-speed video recordings. Both insects are able to skate on the surface of the water using the dorso-apical tracheal gill as an adhesive organ or ‘foot’. Progress relies on the variable adhesion of the foot between ‘slide’ and ‘hold’ periods of the locomotory cycle. The flexural body movements underlying skating in D. aestivalis can be derived directly from the figure-of-eight swimming mechanism used in underwater swimming. The latter is shown to be similar to figure-of-eight swimming in chironomid larvae. This study shows how the deployment of a ‘foot’ enables simple side-to-side flexural movements of the body to be converted into effective locomotion at the air-water interface.

Demonstrations in Sports Training: Communicating a Technique through Parsing and the Return-Practice in the Budo Class

2018 ◽  
Vol 7 (2) ◽  
Author(s):  
Joonas Råman ◽  
Pentti Haddington
Keyword(s):  
The Body ◽  
Temporal Relation ◽  
Sports Training ◽  
Body Movements ◽  
Additional Information ◽  
Video Recordings ◽  
Practical Challenge ◽  
The Individual

Abstract Demonstrating a sports technique to students presents coaches and teachers a practical challenge: How to communicate a multi-phased and fleeting movement of the body effectively and in a manner which also makes clear the temporal relation of the individual phases of the movement? By using video-based methods and video recordings collected in budo sports training, this paper illustrates how teachers parse a complicated and fast-paced technique into individual steps by resorting to talk and embodied means. Furthermore, we examine how the teachers can move back and forth between these steps with an interactional practice we call ‘return-practice’. By employing this practice, the teachers provide additional information regarding particular steps, highlight the simultaneous nature of particular body movements, demonstrate alternative ways of performing the technique, and illustrate the consequences of the incorrect performance of these steps. The linguistic design of the ‘return-practice’ is shown to differ in the above four functions.

scholarly journals A Remote Sensor System Based on TDLAS Technique for Ammonia Leakage Monitoring

Sensors ◽  
2021 ◽  
Vol 21 (7) ◽  
pp. 2448
Author(s):  
Hongbin Lu ◽  
Chuantao Zheng ◽  
Lei Zhang ◽  
Zhiwei Liu ◽  
Fang Song ◽  
...  
Keyword(s):  
Signal Processing ◽  
Limit Of Detection ◽  
Processing Technique ◽  
Tunable Diode Laser ◽  
Sensor System ◽  
Signal Processing Technique ◽  
Suppression Effect ◽  
Output Wavelength ◽  
Deviation Analysis ◽  
Remote Sensor

The development of an efficient, portable, real-time, and high-precision ammonia (NH3) remote sensor system is of great significance for environmental protection and citizens’ health. We developed a NH3 remote sensor system based on tunable diode laser absorption spectroscopy (TDLAS) technique to measure the NH3 leakage. In order to eliminate the interference of water vapor on NH3 detection, the wavelength-locked wavelength modulation spectroscopy technique was adopted to stabilize the output wavelength of the laser at 6612.7 cm−1, which significantly increased the sampling frequency of the sensor system. To solve the problem in that the light intensity received by the detector keeps changing, the 2f/1f signal processing technique was adopted. The practical application results proved that the 2f/1f signal processing technique had a satisfactory suppression effect on the signal fluctuation caused by distance changing. Using Allan deviation analysis, we determined the stability and limit of detection (LoD). The system could reach a LoD of 16.6 ppm·m at an average time of 2.8 s, and a LoD of 0.5 ppm·m at an optimum averaging time of 778.4 s. Finally, the measurement result of simulated ammonia leakage verified that the ammonia remote sensor system could meet the need for ammonia leakage detection in the industrial production process.

scholarly journals Application of UAV in Search and Rescue Actions in Underground Mine—A Specific Sound Detection in Noisy Acoustic Signal

Energies ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3725
Author(s):  
Paweł Zimroz ◽  
Paweł Trybała ◽  
Adam Wróblewski ◽  
Mateusz Góralczyk ◽  
Jarosław Szrek ◽  
...  
Keyword(s):  
Signal Processing ◽  
Acoustic Signal ◽  
Processing Technique ◽  
Underground Mine ◽  
Search And Rescue ◽  
Reference Spectrum ◽  
Signal Processing Technique ◽  
Time Frequency ◽  
Communication Device ◽  
Frequency Representation

The possibility of the application of an unmanned aerial vehicle (UAV) in search and rescue activities in a deep underground mine has been investigated. In the presented case study, a UAV is searching for a lost or injured human who is able to call for help but is not able to move or use any communication device. A UAV capturing acoustic data while flying through underground corridors is used. The acoustic signal is very noisy since during the flight the UAV contributes high-energetic emission. The main goal of the paper is to present an automatic signal processing procedure for detection of a specific sound (supposed to contain voice activity) in presence of heavy, time-varying noise from UAV. The proposed acoustic signal processing technique is based on time-frequency representation and Euclidean distance measurement between reference spectrum (UAV noise only) and captured data. As both the UAV and “injured” person were equipped with synchronized microphones during the experiment, validation has been performed. Two experiments carried out in lab conditions, as well as one in an underground mine, provided very satisfactory results.

Developmental stages in the Digenea

Parasitology ◽  
1964 ◽  
Vol 54 (2) ◽  
pp. 295-312 ◽  
Author(s):  
Elon E. Byrd ◽  
William P. Maples
Keyword(s):  
Body Wall ◽  
Developmental Stages ◽  
Snail Host ◽  
The Body ◽  
Body Movements ◽  
Hatching Enzyme ◽  
Apical Papilla ◽  
Short Time ◽  
Membranous Body ◽  
Egg Capsule

The naturally oviposited egg of Dasymetra conferta is fully embryonated and it hatches only after it is ingested by the snail host, Physa spp.Hatching appears to be in response to some stimulus supplied by the living snail. The stimulus causes the larva to exercise a characteristic series of body movements and to liberate a granular sustance (hatching enzyme) from the larger pair of its cephalic glands. This enzyme reacts with the vitelline fluid to create pressure within the egg capsule, and with the cementum of the operculum, so that it may be lifted away. The larva's escape from the shell, therefore, is due to a combination of pressure and body movements.The hatched larva has a membranous body wall, supporting six epidermal plates, an apical papilla, two penetration glands and a central matrix (the presumptive brood mass).It lives for about an hour within the snail and during this time there is a reorganization of the central matrix which terminates in the formation of an 8-nucleated syncytial brood mass.The miracidial ‘case’, consisting of the body wall and the epidermal plates, ultimately ruptures to liberate the brood mass. Once the brood mass is free it penetrates through the gut wall in an incredibly short time.

A Palmprint Recognition Approach Based on Image Segmentation of Region of Interest

2016 ◽  
Vol 30 (02) ◽  
pp. 1656002 ◽  
Author(s):  
Qing E Wu ◽  
Zhiwu Chen ◽  
Ruijie Han ◽  
Cunxiang Yang ◽  
Yuhao Du ◽  
...  
Keyword(s):  
Image Segmentation ◽  
Wavelet Transform ◽  
Recognition Rate ◽  
Region Of Interest ◽  
Palmprint Recognition ◽  
Characteristic Points ◽  
Positioning Method ◽  
Roi Extraction ◽  
Energy Feature

To carry out an effective recognition for palmprint, this paper presents an algorithm of image segmentation of region of interest (ROI), extracts the ROI of a palmprint image and studies the composing features of palmprint. This paper constructs a coordinate by making use of characteristic points in the palm geometric contour, improves the algorithm of ROI extraction and provides a positioning method of ROI. Moreover, this paper uses the wavelet transform to divide up ROI, extracts the energy feature of wavelet, gives an approach of matching and recognition to improve the correctness and efficiency of existing main recognition approaches, and compares it with existing main approaches of palmprint recognition by experiments. The experiment results show that the approach in this paper has the better recognition effect, the faster matching speed, and the higher recognition rate which is improved averagely by 2.69% than those of the main recognition approaches.

Hydrodynamics and behaviour of Simuliidae larvae (Diptera)

1986 ◽  
Vol 64 (6) ◽  
pp. 1295-1309 ◽  
Author(s):  
M. M. Chance ◽  
D. A. Craig
Keyword(s):  
Boundary Layer ◽  
Lower Boundary ◽  
The Body ◽  
The Other ◽  
Avoidance Reaction ◽  
Larval Body ◽  
Video Recordings ◽  
Von Karman ◽  
Von Kármán ◽  
Lower Boundary Layer

Detailed water flow around larvae of Simulium vittatum Zett. (sibling IS-7) was investigated using flow tanks, aluminium flakes, pigment, still photography, cinematography, and video recordings. Angle of deflection of a larva from the vertical has a hyperbolic relationship to water velocity. Velocity profiles around larvae show that the body is in the boundary layer. Frontal area of the body decreases as velocity increases. Disturbed larvae exhibit "avoidance reaction" and pull the body into the lower boundary layer. Longitudinal twisting and yawing of the larval body places one labral fan closer to the substrate, the other near the top of the boundary layer. Models and live larvae were used to demonstrate the basic hydrodynamic phenomenon of downstream paired vortices. Body shape and feeding stance result in one of the vortices remaining in the lower boundary layer. The other rises up the downstream side of the body, passes through the lower fan, then forms a von Karman trail of detaching vortices. This vortex entrains particulate matter from the substrate, which larvae then filter. Discharge of water into this upper vortex remains constant at various velocities and only water between the substrate and top of the posterior abdomen is incorporated into it. The upper fan filters water only from the top of the boundary layer. Formation of vortices probably influences larval microdistribution and filter feeding. Larvae positioned side by side across the flow mutually influence flow between them, thus enhancing feeding. Larvae downstream of one another may use information from the von Karman trail of vortices to position themselves advantageously.

EXPRESS: The effect of low frequency equalisation on preference and sensorimotor synchronisation in music

2021 ◽  
pp. 174702182110371
Author(s):  
Scott Beveridge ◽  
Estefanía Cano ◽  
Steffen A. Herff
Keyword(s):  
Body Movement ◽  
Low Frequency ◽  
Empirical Support ◽  
Processing Technique ◽  
Original Version ◽  
Upper Body ◽  
Signal Processing Technique ◽  
Band Energy ◽  
Sensorimotor Synchronisation ◽  
Specific Frequency

Equalisation, a signal processing technique commonly used to shape the sound of music, is defined as the adjustment of the energy in specific frequency components of a signal. In this work we investigate the effects of equalisation on preference and sensorimotor synchronisation in music. Twenty-one participants engaged in a goal-directed upper body movement in synchrony with stimuli equalised in three low-frequency sub-bands (0 - 50 Hz, 50 - 100 Hz, 100 - 200 Hz). To quantify the effect of equalisation, music features including spectral flux, pulse clarity, and beat confidence were extracted from seven differently equalised versions of music tracks - one original and six manipulated versions for each music track. These music tracks were then used in a movement synchronisation task. Bayesian mixed effects models revealed different synchronisation behaviours in response to the three sub-bands considered. Boosting energy in the 100 - 200 Hz sub-band reduced synchronisation performance irrespective of the sub-band energy of the original version. An energy boost in the 0 - 50 Hz band resulted in increased synchronisation performance only when the sub-band energy of the original version was high. An energy boost in the 50 - 100 Hz band increased synchronisation performance only when the sub-band energy of the original version was low. Boosting the energy in any of the three subbands increased preference regardless of the energy of the original version. Our results provide empirical support for the importance of low-frequency information for sensorimotor synchronisation and suggest that the effect of equalisation on preference and synchronisation are largely independent of one another.

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