Oromotor Kinematics of Speech In Children and the Effect of an External Rhythmic Auditory Stimulus

The purpose of this study was to determine the effect of an external auditory rhythmic stimulus on the kinematics of the oromotor musculature during speech production in children and adults. To this effect, the research questions were: 1) Do children entrain labiomandibular movements to an external auditory stimulus? 2) Does the ability to entrain labiomandibular movements to an external auditory stimulus change with age? 3) Does an external auditory stimulus change the coordination and stability of the upper lip, lower lip, and jaw when producing speech sounds? The oromotor kinematics of two groups of children, age eight to ten (n = 6) and eleven to fourteen (n = 6), were compared to the oromotor kinematics of adults (n = 12) while producing bilabial syllables with and without an external auditory stimulus. The kinematic correlates of speech production were recorded using video-based 4-dimensional motion capture technology and included measures of upper lip, lower lip and jaw displacement and their respective derivatives. The Spatiotemporal Index (a single number indication of motor stability and pattern formation) and Synchronization Error (a numerical indication of phase deviations) were calculated for each participant within each condition. There were no statistically significant differences between age groups for the Spatiotemporal Index or for Synchronization Error. Results indicated that there were statistically significant differences in the Spatiotemporal Index for condition; with Post-hoc tests indicating that the difference was between the first condition (no rhythm) and the second condition (self-paced rhythm). Results indicated that both child groups were able to synchronize to an external auditory stimulus. Furthermore, the older child group was able to establish oromotor synchrony with near-adult abilities

2008 Annual Research Symposium Abstract Book

2008 annual volume of abstracts for science research projects conducted by students at Trinity College

Vehicle detection and tracking using wireless sensors and video cameras

This thesis presents the development of a surveillance testbed using wireless sensors and video cameras for vehicle detection and tracking. The experimental study includes testbed design and discusses some of the implementation issues in using wireless sensors and video cameras for a practical application. A group of sensor devices equipped with light sensors are used to detect and localize the position of moving vehicle. Background subtraction method is used to detect the moving vehicle from the video sequences. Vehicle centroid is calculated in each frame. A non-linear minimization method is used to estimate the perspective transformation which project 3D points to 2D image points. Vehicle location estimates from three cameras are fused to form a single trajectory representing the vehicle motion. Experimental results using both sensors and cameras are presented. Average error between vehicle location estimates from the cameras and the wireless sensors is around 0.5ft

Wind tunnel pressure study and Euler code validation of a missile configuration with 77 deg swept delta wings at supersonic speeds

A wind-tunnel pressure study was conducted on an axisymmetric missile configuration in the Unitary Plan Wind Tunnel at NASA Langley Research Center. The Mach numbers ranged from 1.70 to 2.86 and the angles of attack ranged from minus 4 degrees to plus 24 degrees. The computational accuracy for limited conditions of a space-marching Euler code was assessed

Biplanar Fluoroscopic Analysis of in vivo Hindfoot Kinematics During Ambulation

The overall goal of this project was to develop and validate a biplanar fluoroscopic system and integrated software to assess hindfoot kinematics. Understanding the motion of the foot and ankle joints may lead to improved treatment methods in persons with foot and ankle pathologies. During gait analysis, skin markers are placed on the lower extremities, which are defined as four rigid-body segments with three joints representing the hip, knee and ankle. This method introduces gross assumptions on the foot and severely limits the analysis of in depth foot mechanics. Multi-segmental models have been developed, but are susceptible to skin motion artifact error. Intra-cortical bone pins studies provide higher accuracy, but are invasive. This dissertation developed and validated a noninvasive biplane fluoroscopy system to overcome the skin motion artifacts and rigid-body assumptions of conventional foot motion analysis. The custom-built biplane fluoroscopy system was constructed from two fluoroscopes separated by 60°, attached to a custom walkway with an embedded force plate. Open source software was incorporated to correct the image distortion and calibrate the capture volume. This study was the first that quantified the cross-scatter contamination in a biplane fluoroscopic system and its effects on the accuracy of marker-based tracking. A cadaver foot study determined the static and dynamic error of the biplane fluoroscopic system using both marker-based and model-based tracking algorithms. The study also developed in vivo 3D kinematic models of the talocrural and subtalar joints during the stance phase of gait. Cross-scatter degradation showed negligible effects in the smallest phantom, suggesting negligible motion tracking error due to cross scatter for distal extremities. Marker-based tracking error had a maximum absolute mean error of 0.21 (± 0.15) in dynamic trials. Model-based tracking results compared to marker-based had an overall dynamic RMS average error of 0.59 mm. Models were developed using custom algorithms to determine talocrural and subtalar joint 3D kinematics. The models offer a viable, noninvasive method suitable for quantifying hindfoot kinematics. Patients with a variety of adult and pediatric conditions which affect foot and ankle dynamics during walking may benefit from this work

Aeronautical engineering, a continuing bibliography with indexes

This bibliography lists 419 reports, articles and other documents introduced into the NASA scientific and technical information system in March 1985

Effective Step to Real-time Implementation of Accident Detection System Using Image Processing

Studies in the past have shown that number of traffic related fatalities is highly dependent on the emergency response time after the occurrence of an accident. Also traffic intersections were found to be one of the most vulnerable places for occurrence of an accident. Therefore there is a need to reduce the emergency response time by alerting the emergency response team by an automated accident detection system at traffic intersections, once an accident is detected. The goal of this project is develop an accident detection system at traffic intersections that is capable of operating in real-time with good performance rate. Therefore an accident detection system was developed which uses the vehicle parameters such as the speed and trajectory and other features such as area, orientation and position of the vehicle. Since one of the key elements in accident detection step is accurate tracking of moving vehicles, more focus was given to vehicle detection and tracking step. In this work, a tracking algorithm that uses a weighted combination of low-level features extracted from moving vehicles and low-level vision analysis on vehicle regions extracted from different frames is implemented. The speed of the tracked vehicles are calculated and along with the features extracted from the tracked vehicle, an accident detection system is designed which validates the factors cueing the occurrence of an accident. Once an accident is detected, the user is signaled about the occurrence of an accident. The detection and tracking performance of the algorithm was around 90% for two test videos used and collision detection system produced a correct detection rate of 87.5% for the test crashes simulated in the test bed setup in the laboratory. Overall the algorithm shows promise since it has a processing rate of 5frames/sec with good collision detection performance. With more test crashes and real-crashes data training, the performance of the algorithm is expected to improve.School of Electrical & Computer Engineerin

Sviluppo di un tool con Smart Analyzer per l'applicazione della calibrazione multipla alla stima della cinematica dell'arto superiore

Questo lavoro consiste nello sviluppo di un protocollo per l’analisi cinematica dell’arto superiore. Sono stati valutati diversi gesti motori per i quali si è utilizzato inizialmente l’approccio CAST nella valutazione dei punti di repere maggiormente affetti da artefatti ATM . In secondo luogo la calibrazione è stata migliorata utilizzando il metodo della calibrazione multipla. I risultati ottenuti dalle diverse calibrazioni sono stati poi messi a confront