Download or read book Speech Intelligibility with Helicopter Noise Tests of Three Helmet Mounted Communication Systems written by and published by . This book was released on 2004 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Military aviator helmet communications systems are designed to enhance speech intelligibility (SI) in background noise and reduce exposure to harmful levels of noise. Some aviators, over the course of their aviation career, develop noise-induced hearing loss that may affect their ability to perform required tasks. New technology can improve SI in noise for aviators with normal hearing as well as those with hearing loss. SI in noise scores were obtained from 40 rotary-wing aviators (20 with normal hearing and 20 with hearing-loss waivers). There were three communications systems evaluated: a standard SPH-4B, an SPH-4B aviator helmet modified with communications earplug (CEP), and an SPH-4B modified with active noise reduction (ANR). Subjects' SI was better in noise with newer technologies than with the standard issue aviator helmet. A significant number of aviators on waivers for hearing loss performed within the range of their normal hearing counterparts when wearing the newer technology. The rank order of perceived speech clarity was 1) CEP, 2) ANR, and 3) unmodified SPH-4B. To insure optimum SI in noise for rotary-wing aviators, consideration should be given to retrofitting existing aviator helmets with new technology, and incorporating such advances in communication systems of the future. Review of standards for determining fitness to fly is needed.
Download or read book Index Medicus written by and published by . This book was released on 2004 with total page 2432 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vols. for 1963- include as pt. 2 of the Jan. issue: Medical subject headings.
Download or read book Comparison of Speech Intelligibility in Cockpit Noise Using Sph 4 Flight Helmet with and Without Active Noise Reduction written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-11 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: Active Noise Reduction (ANR) is a new technology which can reduce the level of aircraft cockpit noise that reaches the pilot's ear while simultaneously improving the signal to noise ratio for voice communications and other information bearing sound signals in the cockpit. A miniature, ear-cup mounted ANR system was tested to determine whether speech intelligibility is better for helicopter pilots using ANR compared to a control condition of ANR turned off. Two signal to noise ratios (S/N), representative of actual cockpit conditions, were used for the ratio of the speech to cockpit noise sound pressure levels. Speech intelligibility was significantly better with ANR compared to no ANR for both S/N conditions. Variability of speech intelligibility among pilots was also significantly less with ANR. When the stock helmet was used with ANR turned off, the average PB Word speech intelligibility score was below the Normally Acceptable level. In comparison, it was above that level with ANR on in both S/N levels. Chan, Jeffrey W. and Simpson, Carol A. Unspecified Center NAS2-12425; NAS2-13188; RTOP 505-61-51...
Download or read book American National Standard written by Accredited Standards Committee S3, Bioacoustics and published by . This book was released on 1990 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook of Warnings written by Michael S. Wogalter and published by CRC Press. This book was released on 2006-01-20 with total page 872 pages. Available in PDF, EPUB and Kindle. Book excerpt: A technical discussion that includes theory, research, and application, this book describes warning design standards and guidelines; aspects of law relevant to warnings such as government regulations, case/trial litigation, and the role of expert testimony in these cases; and international, health/medical, and marketing issues. Broken into thirteen
Download or read book Comparison of Speech Intelligibility in Cockpit Noise Using SPH 4 Flight Helmet with and Without Active Noise Reduction written by and published by . This book was released on 1990 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: Active Noise Reduction (ANR) is a new technology which can reduce the level of aircraft cockpit noise that reaches the pilot's ear while simultaneously improving the signal-to-noise ratio for voice communications and other information-bearing sound signals in the cockpit. A miniature, ear-cup mounted ANR system, developed by Royal Aerospace Establishment, Farnborough, United Kingdom, was tested by U.S. Army Aeroflightdynamics Directorate, Simulation and Aircraft Systems Division, Crew Station Research and Development Branch to determine whether speech intelligibility is better for helicopter pilots using ANR compared to a control condition of ANR turned off. The ANR system was installed in a stock Army SPH-4 flight helmet, and tested in a background of recorded AH-1S (Cobra) cockpit noise, using phonetically balanced word lists, per MIL-STD-1472C. Two signal-to-noise ratios (S/N), representative of actual cockpit conditions, were used: 0 dB and +10 dB for the ratio of the speech to cockpit noise sound pressure levels. Speech intelligibility was significantly better with ANR compared to no ANR for both S/N conditions. Variability of speech intelligibility among pilots was also significantly less with ANR. When the stock helmet was used with ANR turned off, the average PB word speech intelligibility score was below the Normally Acceptable level, per MIl-STD-1472C in the 0 dB S/N levels and exceeded the Exceptionally High Intelligibility level with S/N +10 dB. Keywords: Cockpit communications, Active noise reduction.
Download or read book Helmet Mounted Displays written by Clarence E. Rash and published by SPIE Press. This book was released on 2000 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: The incorporation of technology into aviation has been exponential. Advancements in microelectronics, stealth technology, engine design, and electronic sensors and displays have converted simple aircraft into formidable flying machines. In this book, recognised experts in aviation helmet-mounted displays (HMDs) summarise 25 years of knowledge and experience in the area of HMD visual, acoustic, and biodynamic performance, and user interface issues such as sizing, fitting, and emergency egress.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1990 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effect of Helicopter Noise on Communication and Hearing written by Thomas A. Giordano and published by . This book was released on 1973 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt: STEM INTELLIGIBILITY ARE SERIOUS ONES. The effort described by this report is aimed at reducing the sound pressure levels at the aviator's ears while maintaining high intelligibility and quality in the communication system. The overall problem is first defined. The noise levels inside all areas of the CH-47 were found to exceed the hearing damage risk criteria set forth by the Surgeon General. Even with hearing protectors, the aviator is limited to the time he may fly without undue risk to his hearing. The electrical characteristics of the communication system were determined. Non-linear frequency responses of the microphone and earcup were detected. These resonances cause emphasis of those frequencies in which the ear is most sensitive. The poor noise cancelling ability of the M-87 microphone at high frequencies cause low signal to noise ratios in the communication system. An intelligibility vs. in-ear dBA level study was run to evaluate the potential success of an 'ideal' perfect noise cancelling microphone and other microphone modifications.
Download or read book Audio Effectiveness in Aviation written by North Atlantic Treaty Organization. Advisory Group for Aerospace Research and Development. Aerospace Medical Panel. Symposium and published by . This book was released on 1997 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA SP written by and published by . This book was released on 1990 with total page 536 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Emergency Medical Services 2 Volumes written by Jane H. Brice and published by John Wiley & Sons. This book was released on 2021-11-08 with total page 1187 pages. Available in PDF, EPUB and Kindle. Book excerpt: The two-volume Emergency Medical Services: Clinical Practice and Systems Oversight delivers a thorough foundation upon which to succeed as an EMS medical director and prepare for the NAEMSP National EMS Medical Directors Course and Practicum. Focusing on EMS in the 'real world', the book offers specific management tools that will be useful in the reader's own local EMS system and provides contextual understanding of how EMS functions within the broader emergency care system at a state, local, and national level. The two volumes offer the core knowledge trainees will need to successfully complete their training and begin their career as EMS physicians, regardless of the EMS systems in use in their areas. A companion website rounds out the book's offerings with audio and video clips of EMS best practice in action. Readers will also benefit from the inclusion of: A thorough introduction to the history of EMS An exploration of EMS airway management, including procedures and challenges, as well as how to manage ventilation, oxygenation, and breathing in patients, including cases of respiratory distress Practical discussions of medical problems, including the challenges posed by the undifferentiated patient, altered mental status, cardiac arrest and dysrhythmias, seizures, stroke, and allergic reactions An examination of EMS systems, structure, and leadership
Download or read book AGARD Index of Publications written by North Atlantic Treaty Organization. Advisory Group for Aerospace Research and Development and published by . This book was released on 1995 with total page 614 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aeronautical Engineering written by and published by . This book was released on 1991 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: A selection of annotated references to unclassified reports and journal articles that were introduced into the NASA scientific and technical information system and announced in Scientific and technical aerospace reports (STAR) and International aerospace abstracts (IAA).
Download or read book Proceedings of the Annual Symposium SAFE Association written by SAFE Association (U.S.). Symposium and published by . This book was released on 1991 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Emergency Medical Services written by Jane H. Brice and published by John Wiley & Sons. This book was released on 2021-08-12 with total page 1184 pages. Available in PDF, EPUB and Kindle. Book excerpt: The two-volume Emergency Medical Services: Clinical Practice and Systems Oversight delivers a thorough foundation upon which to succeed as an EMS medical director and prepare for the NAEMSP National EMS Medical Directors Course and Practicum. Focusing on EMS in the 'real world', the book offers specific management tools that will be useful in the reader's own local EMS system and provides contextual understanding of how EMS functions within the broader emergency care system at a state, local, and national level. The two volumes offer the core knowledge trainees will need to successfully complete their training and begin their career as EMS physicians, regardless of the EMS systems in use in their areas. A companion website rounds out the book's offerings with audio and video clips of EMS best practice in action. Readers will also benefit from the inclusion of: A thorough introduction to the history of EMS An exploration of EMS airway management, including procedures and challenges, as well as how to manage ventilation, oxygenation, and breathing in patients, including cases of respiratory distress Practical discussions of medical problems, including the challenges posed by the undifferentiated patient, altered mental status, cardiac arrest and dysrhythmias, seizures, stroke, and allergic reactions An examination of EMS systems, structure, and leadership
Download or read book Noise and Military Service written by Institute of Medicine and published by National Academies Press. This book was released on 2006-01-20 with total page 339 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Institute of Medicine carried out a study mandated by Congress and sponsored by the Department of Veterans Affairs to provide an assessment of several issues related to noise-induced hearing loss and tinnitus associated with service in the Armed Forces since World War II. The resulting book, Noise and Military Service: Implications for Hearing Loss and Tinnitus, presents findings on the presence of hazardous noise in military settings, levels of noise exposure necessary to cause hearing loss or tinnitus, risk factors for noise-induced hearing loss and tinnitus, the timing of the effects of noise exposure on hearing, and the adequacy of military hearing conservation programs and audiometric testing. The book stresses the importance of conducting hearing tests (audiograms) at the beginning and end of military service for all military personnel and recommends several steps aimed at improving the military services' prevention of and surveillance for hearing loss and tinnitus. The book also identifies research needs, emphasizing topics specifically related to military service.
