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A Model To Predict The Reflectance From A Concrete Surface As A Function Of The Sun-Object-Image Angular Relationship, George C. Grogan
A Model To Predict The Reflectance From A Concrete Surface As A Function Of The Sun-Object-Image Angular Relationship, George C. Grogan
Theses
A study was made of the variation in the reflectance of a concrete sample as the sun-object-image angular relationship was varied. The research work was performed in the controlled conditions of a laboratory so that atmospheric effects could be neglected. Reflectance measurements were taken from a. concrete sample whose surface roughness had been measured. Both specular and diffuse illumination in the red (630 - 680nm) wavelength region of the visible spectrum were measured. A model which can be used to predict the reflectance value for a given sun-object-image angular relationship was developed. Actual reflectance measurements taken outdoors agreed to within …
Optical Spectrometry Via Photoelectron Spectroscopy, Marshall Clemens
Optical Spectrometry Via Photoelectron Spectroscopy, Marshall Clemens
Theses
The photoelectric effect has long been a phenomenon of great scientific and practical interest. Its application to photomultiplier and image pickup tubes has yielded a wealth of instruments. Most recently the field of photoelectron spectroscopy has developed as a tool for chemical analysis.
The Effect Of Microscope Scale Reticle Design On Variance Of Measurement, David D. Rockafellow
The Effect Of Microscope Scale Reticle Design On Variance Of Measurement, David D. Rockafellow
Theses
Little work has been documented regarding the design of optical instrument scale reticles. Reticle is the word used to describe both scales and crosshairs used in the eyepiece of an optical instrument. An ergonomic (the relation of man to his working environment) experiment was performed in which thirteen different scale reticles were designed, manufactured and tested. The design parameters tested were scale spacing, line height, and line thickness. The testing consisted of thirty observers measuring a circular test object through a microscope with each scale reticles. The results, taking into consideration both variance in measurement and observer comments, showed the …
A Study Of Comparable Identifiably Predictions Of Some Resolving Power Targets By Fourier Spectra Considerations, James Greene
A Study Of Comparable Identifiably Predictions Of Some Resolving Power Targets By Fourier Spectra Considerations, James Greene
Theses
This report documents a study conducted to examine the correlation between identification thresholds and difference spectra of some resolving power target characters. The experiment included the USAF Tri-bar target, the RIT Alpha-numeric Resolving Power Target, and a set of targets called the Granger Modified Tri-bar targets. Assuming that target identification is a filtering process and primarily a function of its frequency spectrum, this study began with a prediction of targets that would have equal identification thresholds from difference spectra considerations. Target images were viewed at various sizes to confirm/refute the original hypothesis. The USAF targets demonstrated adequate control of experimental …