2,166 research outputs found
Cardiovascular instrumentation for spaceflight
The observation mechanisms dealing with pressure, flow, morphology, temperature, etc. are discussed. The approach taken in the performance of this study was to (1) review ground and space-flight data on cardiovascular function, including earlier related ground-based and space-flight animal studies, Mercury, Gemini, Apollo, Skylab, and recent bed-rest studies, (2) review cardiovascular measurement parameters required to assess individual performance and physiological alternations during space flight, (3) perform an instrumentation survey including a literature search as well as personal contact with the applicable investigators, (4) assess instrumentation applicability with respect to the established criteria, and (5) recommend future research and development activity. It is concluded that, for the most part, the required instrumentation technology is available but that mission-peculiar criteria will require modifications to adapt the applicable instrumentation to a space-flight configuration
In-Suit Doppler Technology Assessment
The objective of this program was to perform a technology assessment survey of non-invasive air embolism detection utilizing Doppler ultrasound methodologies. The primary application of this technology will be a continuous monitor for astronauts while performing extravehicular activities (EVA's). The technology assessment was to include: (1) development of a full understanding of all relevant background research; and (2) a survey of the medical ultrasound marketplace for expertise, information, and technical capability relevant to this development. Upon completion of the assessment, LSR was to provide an overview of technological approaches and R&D/manufacturing organizations
NASA Tech Briefs Index, 1977, volume 2, numbers 1-4
Announcements of new technology derived from the research and development activities of NASA are presented. Abstracts, and indexes for subject, personal author, originating center, and Tech Brief number are presented for 1977
Can ultrasonic doppler help detecting nasality for silent speech interfaces?: An exploratory analysis based on alignement of the doppler signal with velum aperture information from real-time MRI
This paper describes an exploratory analysis on the usefulness of the information made available from
Ultrasonic Doppler signal data collected from a single speaker, to detect velum movement associated to
European Portuguese nasal vowels. This is directly related to the unsolved problem of detecting nasality in
silent speech interfaces. The applied procedure uses Real-Time Magnetic Resonance Imaging (RT-MRI),
collected from the same speaker providing a method to interpret the reflected ultrasonic data. By ensuring
compatible scenario conditions and proper time alignment between the Ultrasonic Doppler signal data and
the RT-MRI data, we are able to accurately estimate the time when the velum moves and the type of
movement under a nasal vowel occurrence. The combination of these two sources revealed a moderate
relation between the average energy of frequency bands around the carrier, indicating a probable presence
of velum information in the Ultrasonic Doppler signalinfo:eu-repo/semantics/acceptedVersio
Aerospace Medicine and Biology: A continuing bibliography with indexes, supplement 182, July 1978
This bibliography lists 165 reports, articles, and other documents introduced into the NASA scientific and technical information system in June 1978
Multimodal corpora for silent speech interaction
A Silent Speech Interface (SSI) allows for speech communication to take place in the absence of an acoustic signal. This type of
interface is an alternative to conventional Automatic Speech Recognition which is not adequate for users with some speech
impairments or in the presence of environmental noise. The work presented here produces the conditions to explore and analyze
complex combinations of input modalities applicable in SSI research. By exploring non-invasive and promising modalities, we have
selected the following sensing technologies used in human-computer interaction: Video and Depth input, Ultrasonic Doppler sensing
and Surface Electromyography. This paper describes a novel data collection methodology where these independent streams of
information are synchronously acquired with the aim of supporting research and development of a multimodal SSI. The reported
recordings were divided into two rounds: a first one where the acquired data was silently uttered and a second round where speakers
pronounced the scripted prompts in an audible and normal tone. In the first round of recordings, a total of 53.94 minutes were captured
where 30.25% was estimated to be silent speech. In the second round of recordings, a total of 30.45 minutes were obtained and 30.05%
of the recordings were audible speech.info:eu-repo/semantics/publishedVersio
Aerospace Medicine and Biology: A continuing bibliography, supplement 191
A bibliographical list of 182 reports, articles, and other documents introduced into the NASA scientific and technical information system in February 1979 is presented
- …