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Displaying 51901 - 51925 of 74256

Managing Role/Permission Relationships Using Object Access Types

October 23, 1998
Author(s)
John Barkley, Anthony V. Cincotta
The role metaphor in Role Based Access Control (RBAC) is particularly powerful in its ability to express access policy in terms of the way in which administrators view organizations. Much of the effort in providing administrative tools for RBAC has been

Role Based Access Control on MLS Systems Without Kernel Changes

October 23, 1998
Author(s)
David R. Kuhn
Role based access control (RBAC) is attracting increasing attention as a security mechanism for both commercial and many military systems. This paper shows how RBAC can be implemented using the mechanisms available on traditional multi-level security

Software Standards

October 22, 1998
Author(s)
D. Richard Kuhn, Thomas R. Rhodes, Christopher E. Dabrowski
This article describes software standards and their characteristics. Development considerations for programmers using standards are explained as well.

Vibrationally-Resolved Sum-Frequency Generation With Broad Bandwidth Infrared Pulses

October 15, 1998
Author(s)
Lee J. Richter, T Petralli-Mallow, John C. Stephenson
We present a novel procedure for vibrationally-resolved sum-frequency generation (SFG) in which a broad-bandwidth IR pulse is mixed with a narrow-bandwidth visible pulse. The resultant SFG spectrum is dispersed with a spectrograph and detected in parallel

A Wavelength Availability Restriction Protocol for Improved WDM Network Access

October 13, 1998
Author(s)
M R. Frey, T D. Ndousse, David H. Su
Future broadband communication networks are intended to accommodate dissimilar traffic classes with different negotiated qualities of service. A family of network access protocols is introduced whose members artificially restrict the number of calls from

Microwave Power Handling in Engineered Yba 2 Cu 3 O^d6-d Grain Boundaries

October 12, 1998
Author(s)
Y. M. Habib, D. E. Oates, G. Dresselhaus, M. Dresselhaus, Leila R. Vale, Ronald H. Ono
Microwave-frequency (rf) power-dependence measurements performed on thin-film Yba 2Cu 3O^d7-δ grain boundaries engineered on sapphire bicrystal substrates with misorientation angles of θ=20, 50, 100, and 240 are presented. The data are compared to

Inheritance Properties of Role Hierarchies

October 9, 1998
Author(s)
Wayne Jansen
Role Based Access Control (RBAC) refers to a class of security mechanisms that mediate access to resources through organizational identities called roles. A number of models have been published that formally describe the basic properties of RBAC. One

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
Displaying 51901 - 51925 of 74256
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