| Visual Scene Effects on the Somatogravic Illusion |
DEC 97 |
27 pages |
| Authors:
Charles S. Lessard; Fred H. Previc; Brian Self; Jeremy Beer; KRUG LIFE SCIENCES HOUSTON TX
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 | The somatogravic illusion is a dangerous illusion that is believed to have caused a large number of mishaps in civilian and military aviation over the years. This illusion is usually experienced during forward acceleration, which creates a backward inertial force that combines with gravity to produce a resultant gravito inertial vector rotated backward from the pilot; hence, the pilot perceives a pitching up of the aircraft. The false climb illusion ... |
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| Electrophysiological Correlates of +Gz Tolerance Comparison Study |
JUL 96 |
30 pages |
| Authors:
Charles S. Lessard; Jonathan French; Paul Werchan; ARMSTRONG LAB WRIGHT-PATTERSON AFB OH CREW SYSTEMS DIRECTORATE
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| This report describes an evaluation of a helmet mounted system; presently, under development for determination of +Gz induced loss of consciousness (G-LOC). The G-LOC detection system, self-contained and built into a standard flight helmet, consists of a set of dry electrodes, preamplifiers, signal conditioning circuits, and analog-to-digital converter for acquisition of the electroencephalogram (EEG) and electro-oculogram (EOG) signals. The study compares the the EEG activity acquired with the dry electrode ... |
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| Temperature Measurement and Monitoring Devices |
AUG 1988 |
24 pages |
| Authors:
Charles S. Lessard; Wing C. Wong; Glenn F. Schmidt; TEXAS A AND M UNIV COLLEGE STATION BIOENGINEERING PROGRAM
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| The principal aim of this study was to evaluate current literature on noninvasive methods and instruments on core temperature (body's temperature in deep tissue, i.e., heart). A specific goal is a conceptual design for a device to measure core temperature through chemical defense clothing. This report reviews temperature sensing devices, infrared |
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| Vital Signs Rate Meter |
SEP 87 |
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| Authors:
Charles S. Lessard; Wing C. Wong; Eric T. Schorsch; Jae-Joong Im; Steve Mesibov; TEXAS A AND M UNIV COLLEGE STATION BIOENGINEERING PROGRAM
|
 | The design of the vital signs rate meter described in this report is an outgrowth from previous studies on noninvasive measurement methods and systems for vital signs detection. The purpose of the vital signs rate meter is to assist medical technicians in performance of triage within a toxic environment. Two of the primary physiological measures obtained during an emergency assessment are respiration rate and heart rate. The vital signs rate ... |
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| Discriminant Analysis of Respiratory Sounds of Pulmonary Insufficient Patients and Normal Subjects |
APR 87 |
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| Authors:
Charles S. Lessard; Wing C. Wong; TEXAS A AND M UNIV COLLEGE STATION BIOENGINEERING PROGRAM
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| Respiration is one of the physiological functions of concern when a patient is under examination or treatment. A clinical relationship between respiratory sounds and gross respiratory pathology was established in the nineteenth century. Previous research indicates that respiratory sounds measured at the trachea undergo very little filtering. Charbonneau stated that the sound level is higher at the trachea than at any other point of the chest or back and the ... |
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| Cluster Analysis of Respiratory Sounds of Pulmonary Insufficient Patients and Normal Subjects |
OCT 86 |
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| Authors:
Charles S. Lessard; Brenda A. Wolf; Wing C. Wong; TEXAS A AND M UNIV COLLEGE STATION DEPT OF INDUSTRIAL ENGINEERING
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| Respiration is one of the physiological functions of concern when a patient is under examination or treatment. A clinical relationship between respiratory sounds and gross respiratory pathology was established in the nineteenth century. Auscultation of respiratory sounds, however, is very subjective. Due to the subjectiveness, there are varying degrees of acceptance of respiratory sounds as a clinical sign. to alleviate the problem, various researchers have studied respiratory sounds to explore ... |
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| Evaluation of Noninvasive Measurement Methods and Systems for Application in Vital Signs Detection. Part 1. Literature Review |
MAR 86 |
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| Authors:
Charles S. Lessard; Wing C. Wong; TEXAS A AND M UNIV COLLEGE STATION BIOENGINEERING PROGRAM
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| The principal aim of this study was to evaluate current literature on noninvasive methods and instruments to provide recommendations on direction of technical development which could lead to a system or device for measuring vital signs of incapacitated military personnel in a toxic field environment. The specific aims of this study were: 1) to determine the set of physiological parameters most likely to give the condition of an individual; 2) ... |
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| Evaluation of Noninvasive Measurement Methods and Systems for Application in Vital Signs Detection. Part 2. Breadboard Design of a Vital Sign Detector |
MAR 86 |
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| Authors:
Charles S. Lessard; Wing C. Wong; Andrew Yee; TEXAS A AND M UNIV COLLEGE STATION BIOENGINEERING PROGRAM
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| In the event of chemical warfare, military medical technicians must be able to identify and treat victims exposed to harmful chemical agents. To determine which victims are in need of immediate treatment, a diagnostic tool is needed to help medical technicians in the performance of triage. An evaluation of current literature on noninvasive techniques and systems for physiological measurements indicates that the most promising methods/systems are: 1) an electromechanical device ... |
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| Development of a Period Analysis Computer Program. |
OCT 1973 |
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| Authors:
Charles S. Lessard; Robert A. Balusek; Harry M. Hughes; SCHOOL OF AEROSPACE MEDICINE BROOKS AFB TEX
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| The development of a computer program for decomposition and compression of the electroencephalographic (EEG) signal by means of period analysis is described. The program digitizes four channels of analog EEG signals simultaneously, and determines the time between zero crossings by counting the number of samples in the fundamental EEG signal and its derivative. Measurement vectors, formed from the interval of time between zero crossings, are tallied in histogram frequency bands ... |
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| PERFORMANCE DECREMENT AS A FUNCTION OF SEVEN DAYS OF BEDREST. |
SEP 1970 |
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| Authors:
Ralph W. Trimble; Charles S. Lessard; SCHOOL OF AEROSPACE MEDICINE BROOKS AFB TEX
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| The hypothesis that performance decrements will occur as a function of 7 days of complete bedrest was tested in a study in which healthy, normal, young adult males served as subjects. Results indicate that longer periods of bedrest may be needed before any decrements become observable in this type of study. (Author) |
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| DIGITAL SIMULATION AID IN DESIGNING AN AUTOMATIC EEG ANALYZER. |
JUN 1970 |
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| Authors:
Charles S. Lessard; Harry M. Hughes; SCHOOL OF AEROSPACE MEDICINE BROOKS AFB TEX
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| Through period analysis, analog sleep EEG information was compressed into a series of numbers representing the incidence of intervals generated by zero-crossing of the EEG and its first derivative (digital differential) for 11-min. epochs. The resulting measurement vectors served not only for preliminary assessment of the descriptors as stage discriminators, but also for subjective comparison of EEG signals between leads for the same stages of sleep. In efforts to generate ... |
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| A STUDY OF THE PRIMATE VESTIBULAR SYSTEM. |
JUN 1967 |
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| Authors:
Charles S. Lessard; James R. Gnuse; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OHIO SCHOOL OF ENGINEERING
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| A constant-speed, feedback-controlled apparatus suitable for flight in zero-g aircraft, was designed, modeled, tested and constructed for direct, continuous measurement and readout of eyeball counterroll. The results, using Rhesus monkeys as subjects, were compared with human measurements obtained through an indirect system and were found to be qualitatively similar. Transient responses to a step angular velocity were observed to diminish. Amplitude shifts, bias drifts, and variations in the magnitude of ... |
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