Issue 10 Volume 41 May 16, 2003

of the classifiers using the mixed spectral and dynamic features was excellent but ‘blind’ testing of the classifiers that were
developed (testing against vehicle runs that were not used during classifier development) showed disappointing results.
DTIC
20030034608 ASRC Aerospace Corp., Greenbelt, MD, USA
On the Scaling Laws for Jet Noise in Subsonic and Supersonic Flow
Vu, Bruce; Kandula, Max; [2003]; 18 pp.; In English; 9th AIAA/CEAS Aeroacoustics Conference and Exhibit, 12-14 May
2003, Hilton Head, SC, USA; Original contains black and white illustrations
Contract(s)/Grant(s): NAS10-03006
Report No.(s): KSC-2003-040; Copyright; Avail: CASI; A03, Hardcopy
The scaling laws for the simulation of noise from subsonic and ideally expanded supersonic jets are examined with regard
to their applicability to deduce full scale conditions from small-scale model testing. Important parameters of scale model
testing for the simulation of jet noise are identified, and the methods of estimating full-scale noise levels from simulated scale
model data are addressed. The limitations of cold-jet data in estimating high-temperature supersonic jet noise levels are
discussed. It is shown that the jet Mach number (jet exit velocity/sound speed at jet exit) is a more general and convenient
parameter for noise scaling purposes than the ratio of jet exit velocity to ambient speed of sound. A similarity spectrum is also
proposed, which accounts for jet Mach number, angle to the jet axis, and jet density ratio. The proposed spectrum reduces
nearly to the well-known similarity spectra proposed by Tam for the large-scale and the fine-scale turbulence noise in the
appropriate limit.
Author
Scaling Laws; Jet Aircraft Noise; Computerized Simulation; Supersonic Jet Flow; Subsonic Flow; Scale Models; Data
Processing; Acoustic Velocity; Parameter Identification
20030034660 Bogazici Univ., Istanbul, Turkey
A Wavelet-Based Instrument for Detection of Crackles in Pulmonary Sounds
Kahya, Yasemin P.; Yerer, Serkan; Cerid, Omer; October 25, 2001; 5 pp.; In English
Report No.(s): AD-A410473; No Copyright; Avail: CASI; A01, Hardcopy
Crackles are discontinuous adventitious respiratory sounds, which are considered as signs of various pulmonary,
disorders, therefore their detection is important in the analysis of lung sounds. In this work, an instrument for separating
crackles from stationary, lung sounds and quantifying their characteristics is realized with DSP. The detection algorithm is
based on increasing transient to background ratio by adaptive filtering and implementing nonlinear operators to wavelet based
decomposed lung sounds.
DTIC
Lungs; Detection; Algorithms
20030034690 Naval Undersea Warfare Center, Newport, RI
Sonar Tracking Array
Griffin, Maurice J., Inventor; Aug 2002; 14 pp.; In English
Patent Info.: Filed: 6 Aug. 2002; US-Patent-Appl-SN-10214485
Report No.(s): AD-D020052; No Copyright; Avail: Issuing Activity (Defense Technical Information Center (DTIC))
A sonar array comprising a support structure, an acoustic 7 projector attached to the support structure, and a plurality of
8 directional hydrophones attached to the support structure and 9 arranged so as to surround the acoustic projector. The 10
directional hydrophones are spaced about the acoustic projector. In one embodiment, the array includes means attached to the
12 support structure that allows the support structure to be 13 connected to a device that effects coarse steering of the sonar
14 array.
DTIC
Sonar; Sound Generators; Hydrophones; Directional Antennas
20030034828 Naval Undersea Warfare Center, Newport, RI
Speech to Touch Translator Assembly and Method
Dec 2002; 17 pp.; In English; US-Patent-Appl-SN-10/224230
Report No.(s): AD-D020049; No Copyright; Avail: Issuing Activity (Defense Technical Information Center (DTIC))
A speech to touch translator assembly and method for converting spoken words directed to an operator into tactile
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