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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 181 records · Page 10

Multiple-mask chemical etching

Multiple masking techniques use lateral etching to reduce the total area of the high etch-rate oxide exposed to the chemical etchant. One method uses a short-term etch to remove the top layer from the silicon oxide surface, another acts before the top layer is grown.

Cannon, D. L.↗

Masking of aluminum surface against anodizing

Masking material and a thickening agent preserve limited unanodized areas when aluminum surfaces are anodized with chromic acid. For protection of large areas it combines well with a certain self-adhesive plastic tape.

Crawford, G. B.↗

Errors in Hadamard spectroscopy or imaging caused by imperfect masks

An analysis is given of the errors in Hadamard spectroscopy that are caused by transparent slits in the mask being systematically wider or else narrower than they should be. It is shown that if the input spectrum consists of a single line, the distorted spectrum that is actually calculated consists of this line, plus four small blips. When the transparent slits are too wide, these blips are of equal height and the same sign, one pair surrounding the line, and another pair displaced a certain distance from it. When the slits are too narrow, the displaced blips have the same amplitude but are negative.

Tai, M. H.↗

Mask analysis program

Program uses minimal core and time resources and performs following analysis functions: artwork verification, device identification, nodal analysis, capacitance calculation, and logic equation generation. For data base simplicity, program processing operates on mask data which has been coverted from its original form to orthogonal rectangles.

Martin, M.↗

Selective attention and the auditory vertex potential. 2: Effects of signal intensity and masking noise

A randomized sequence of tone bursts was delivered to subjects at short inter-stimulus intervals with the tones originating from one of three spatially and frequency specific channels. The subject's task was to count the tones in one of the three channels at a time, ignoring the other two, and press a button after each tenth tone. In different conditions, tones were given at high and low intensities and with or without a background white noise to mask the tones. The N sub 1 component of the auditory vertex potential was found to be larger in response to attended channel tones in relation to unattended tones. This selective enhancement of N sub 1 was minimal for loud tones presented without noise and increased markedly for the lower tone intensity and in noise added conditions.

Schwent, V. L.↗

Mask Analysis Program (MAP) reference manual

A document intended to serve as a User's Manual and a Programmer's Manual for the Mask Analysis Program is presented. The first portion of the document is devoted to the user. It contains all of the information required to execute MAP. The remainder of the document describes the details of MAP software logic. Although the information in this portion is not required to run the program, it is recommended that every user review it to gain an appreciation for the program functions.

Mitchell, C. L.↗

Errors in Hadamard spectroscopy or imaging caused by imperfect masks

An analysis is given of the errors in Hadamard spectroscopy that are caused by transparent slits in the mask being systematically wider or narrower than they should be. It is shown that if the input spectrum consists of a single line, the distorted spectrum that is actually calculated consists of this line plus four small blips. When the transparent slits are too wide, these blips are of equal height and the same sign with one pair surrounding the line and another pair 5isplaced a certain distance from it. When the slits are too narrow, the displaced blips have the same amplitude, but are negative. The response to an arbitrary input spectrum is then determined from this. The same method of analysis may also be used to handle other types of errors.

Tai, M. H.↗