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Displaying 55601 - 55625 of 74203

Test Optics Error Removal

March 1, 1996
Author(s)
Christopher J. Evans, R Kestner
Wave-front or surface errors may be divided into rotationally symmetric and nonrotationally symmetric terms. It is shown that if either the test part or the reference surface in an interferometric test is rotated to N equally spaced positions about the

Using Logic to Specify Shapes and Spatial Relations in Design Grammars

March 1, 1996
Author(s)
Scott Chase
Shape algebraic representations provide several advantages over more traditional geometric representations. The use of predicate logic formulations of shape and spatial relations provides a natural, intuitive way to extend shape representations of the

Commercial helium permeation leak standards: Their properties and reliability

February 12, 1996
Author(s)
Patrick J. Abbott, S A. Tison
Standard leaks or leak artifacts are used extensively in industrial and research environments, typically for the calibration of helium leak detectors. The most commonly used leak is the helium permeation type, which uses a glass, quartz, or polymer barrier
Displaying 55601 - 55625 of 74203
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