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Displaying 51851 - 51875 of 74189

Role-Based Access Control Features in Commercial Database Management Systems

October 9, 1998
Author(s)
Ramaswamy Chandramouli, R. Sandhu
This paper analyzes and compares role-based access control (RBAC) features supported in the most recent versions of three popular commercial database management systems: Informix Online Dynamic Server Version 7.2, Oracle Enterprise Server Version 8.0 and

Characterization of High-OD Ultrathin Infrared Neutral Density Filters

October 8, 1998
Author(s)
Simon G. Kaplan, Leonard M. Hanssen, Alan L. Migdall, G Lefever-Button
We have performed transmittance measurements of metal-film neutral density filters on ultrathin polymer substrates using both Fourier-transform infrared spectrometer and laser-based (3.39 mm and 10.6 mm) systems. The use of ultrathin substrates, free of

Characterization of Narrow-Band Infrared Interference Filters

October 8, 1998
Author(s)
Simon G. Kaplan, Leonard M. Hanssen
A Fourier-transform infrared (FT-IR) spectrophotometer system is used to measure the transmittance of infrared band-pass filters as a function of wavelength, temperature, and beam geometry. Measurements are performed using an f/4 beam geometry at normal

FT-IR Based Polarimeter with High-Quality Brewster-Angle Polarizers

October 8, 1998
Author(s)
Simon G. Kaplan, Leonard M. Hanssen
A Fourier transform infrared (FT-IR) spectrometer based broadband infrared polarimeter has been developed around a pair of high-quality Brewster angle polarizers. These polarizers consist of four Ge plates in a chevron geometry and have been measured to

Normal Infrared Spectral Emittance of Al 2 O 3

October 8, 1998
Author(s)
Simon G. Kaplan, Leonard M. Hanssen
We have measured the near-normal ordinary ray transmittance and reflectance of crystalline Al 2O 3 from 1.6 m to 11 m and temperatures from 296 K to 582 K. The absorptance, or emittance, is derived from 1-(T+R), where T and R are the measured transmittance

WebMetrics: A Methodology for Producing Usable Web Sites

October 6, 1998
Author(s)
Jean C. Scholtz
This work describes a methodology for designing and evaluating web sites and web applications. Our methodology is based on the premise that tools and techniques for design and evaluation must be rapid, remote, and automated in order to be useful for web

Data Representation and Handling for Large Image Browsing

October 5, 1998
Author(s)
O E. Kia, A A. Schaff, J J. Sauvola
In this paper we present results of work done on large image browsing. Advances in compression and transmission have allowed efficient usage of storage and transmission resources; however, much work needs to be done in order to integrate such concepts in

Electrical Detection of Defects in SIMOX Buried Oxides: Pipes and Precipitates

October 5, 1998
Author(s)
Peter Roitman, Monica D. Edelstein, S. J. Krause
Two defect types have been identified in the buried oxide of low dose SIMOX: conductive silicon paths through the buried oxide (pipes) and silicon precipitates in the buried oxide. Both types are caused by the same general mechanism; the tendency of the Si

A 400 nm to 2500 nm Absolute Spectral Radiance Comparison Using Filter Radiometers

October 1, 1998
Author(s)
Howard W. Yoon, Bettye C. Johnson, D Kelch, S F. Biggar, P R. Spyak
An integrating sphere source developed by MTL Systems, Inc. was calibrated for them by a commercial standards laboratory traceable to the National Institute of Standards and Technology (NIST), resulting in values of spectral radiance in the 400 nm to 2500

A Fast Pulse Oscilloscope Calibration System

October 1, 1998
Author(s)
J. P. Deyst, Nicholas Paulter, T. Daboczi, Gerard N. Stenbakken, T. M. Souders
A system is described for calibrating high-bandwidth oscilloscopes using pulse signals. The fast pulse oscilloscope calibration system (FPOCS) is to be used to determine the step response parameters for digitizing oscilloscopes having bandwidths of 20 GHz

A Pulse Measurement Intercomparison

October 1, 1998
Author(s)
T. M. Souders, J R. Andrews, A. Caravone, J. P. Deyst, C. Duff, S. Naboicheck
A pulse measurement intercomparison, organized by (NIST) and conducted by the authors in their respective labs, is described. The purpose was to assess the state of the art for time-domain pulse-waveform measurements in the nanosecond regime, and to find

Analytical Study of Residential Buildings With Reflective Roofs

October 1, 1998
Author(s)
Robert R. Zarr
Annual heating (cooling) loads, peak heating (cooling) loads, and exterior roof temperatures for a small compact ranch house are computed using the Thermal Analysis Research Program (TARP) developed at the National Institute of Standards and Technology

Application of Laser Feedback Metrology to a Hexapod Test Strut

October 1, 1998
Author(s)
M Schmidt-Lange, E Amatucci, Albert J. Wavering
A laser position feedback system has been designed to improve the accuracy of strut positioning for the prototype Ingersoll2 Octahedral Hexapod machine installed at National Institute of Standards and Technology (NIST) (Figure 1). Strut laser feedback

Authentication Proxy for the VistA Hospital Information System

October 1, 1998
Author(s)
William J. Majurski
This paper describes the concept and design of an Authentication Proxy, a network service that bridges the security environments (specifically authentication) of an underlying network environment (Windows NT) and the VistA hospital information system. The

Building for Environmental and Economic Sustainability (BEES)

October 1, 1998
Author(s)
Barbara C. Lippiatt
Buildings significantly alter the environment. According to Worldwatch Institute (1), building construction consumes 40 percent of the raw stone, gravel, and sand used globally, and sand used globally each year, and 25 percent of the virgin wood. Buildings
Displaying 51851 - 51875 of 74189
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