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[ReSource: The University of North Texas Research Magazine]

Description: A magazine titled ReSource, The University of North Texas Research Magazine. One of the articles covers the Discipline-Based Art Education style employed by the North Texas Institute for Educators on the Visual Arts and other consortia established and partially funded by the Getty Center for Education in the Arts. There are several other articles in the magazine as well.
Date: 199u
Creator: Guest, Charlotte Menger; Read, Hill Patterson, III; Redding, Rogers W.; Shelton, Susan; Barnes, Carolyn N.; Witt, Peter A. et al.
Partner: UNT Libraries Special Collections

Prototyping Regional Discrimination Tools with Matseis

Description: To facilitate the development testing and comparison of regional seismic discriminants, we have implemented some of the most promising techniques in Matseis, a-Matlab-based seismic processing toolkit. The existing Matseis package provides graphical tools for analyzing seismic data from a network of stations. It can access data via a CSS 3.0 database, or from static files in a format defined by the user. Waveforms are displayed in a record-section format, with overlays for IASPE191 travel-time curves. The user can pick arrivals and locate events, then show the results on a map. Tools are available for spectral and polarization measurements, as well as beam forming and f-k analysis with array data. Additionally, one has full access to the Matlab environment and any functions available there, as well as to portions of the U.S. Department of Energy Knowledge Base. Recently, we have added some new tools to Matseis for calculating regional discrimination measurements. The first of these performs Lg coda analysis as developed by Mayeda and coworkers at Lawrence Livermore National Laboratory (LLNL). Lg coda magnitudes are calculated from the amplitudes of the coda envelopes in narrow frequency bands. Ratios of these amplitudes between high- and low-frequency bands provide a spectral-ratio discriminant for regional events. The second tool we have implemented measures P/Lg phase ratios, using the MDAC technique of Taylor (Los Alamos National Laboratory) and Walter (LLNL). P and Lg amplitudes are obtained at select frequencies, then corrected for source magnitude and propagation path. Finally, we added a tool for analyzing long-period Rayleigh and Love arrivals, useful for moment:magnitude and LQ:LR discrimination. Because all these tools have been written as Matlab functions, they can be easily modified to experiment with different processing details. The performance of the discriminants can be evaluated using any event available in the database.
Date: August 3, 1999
Creator: Chael, Eric; Harris, Mark; Young, Chris; Mayeda, Kevin; Walter, William; Taylor, Steve et al.
Partner: UNT Libraries Government Documents Department

Data Authentication Demonstration for Radionuclide Stations

Description: Data authentication is required for certification of sensor stations in the International Monitoring System (IMS). Authentication capability has been previously demonstrated for continuous waveform stations (seismic and infrasound). This paper addresses data surety for the radionuclide stations in the IMS, in particular the Radionuclide Aerosol Sampler/Analyzer (RASA) system developed by Pacific Northwest National Laboratory (PNNL). Radionuclide stations communicate data by electronic mail using formats defined in IMS 1.0, Formats and Protocols for Messages. An open message authentication standard exists, called S/MIME (Secure/Multipurpose Internet Mail Extensions), which has been proposed for use with all IMS radionuclide station message communications. This standard specifies adding a digital signature and public key certificate as a MIME attachment to the e-mail message. It is advantageous because it allows authentication to be added to all IMS 1.0 messages in a standard format and is commercially supported in e-mail software. For command and control, the RASA system uses a networked Graphical User Interface (GUI) based upon Common Object Request Broker Architecture (CORBA) communications, which requires special authentication procedures. The authors have modified the RASA system to meet CTBTO authentication guidelines, using a FORTEZZA card for authentication functions. They demonstrated signing radionuclide data messages at the RASA, then sending, receiving, and verifying the messages at a data center. They demonstrated authenticating command messages and responses from the data center GUI to the RASA. Also, the particular authentication system command to change the private/public key pair and retrieve the new public key was demonstrated. This work shows that data surety meeting IMS guidelines may be immediately applied to IMS radionuclide systems.
Date: August 3, 1999
Creator: Harris, Mark; Herrington, Pres; Miley, Harry; Ellis, J. Edward; McKinnon, David & St. Pierre, Devon
Partner: UNT Libraries Government Documents Department