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Unique Signal mathematical analysis task group FY03 status report.

Description: The Unique Signal is a key constituent of Enhanced Nuclear Detonation Safety (ENDS). Although the Unique Signal approach is well prescribed and mathematically assured, there are numerous unsolved mathematical problems that could help assess the risk of deviations from the ideal approach. Some of the mathematics-based results shown in this report are: 1. The risk that two patterns with poor characteristics (easily generated by inadvertent processes) could be combined through exclusive-or mixing to generate an actual Unique Signal pattern has been investigated and found to be minimal (not significant when compared to the incompatibility metric of actual Unique Signal patterns used in nuclear weapons). 2. The risk of generating actual Unique Signal patterns with linear feedback shift registers is minimal, but the patterns in use are not as invulnerable to inadvertent generation by dependent processes as previously thought. 3. New methods of testing pair-wise incompatibility threats have resulted in no significant problems found for the set of Unique Signal patterns currently used. Any new patterns introduced would have to be carefully assessed for compatibility with existing patterns, since some new patterns under consideration were found to be deficient when associated with other patterns in use. 4. Markov models were shown to correspond to some of the engineered properties of Unique Signal sequences. This gives new support for the original design objectives. 5. Potential dependence among events (caused by a variety of communication protocols) has been studied. New evidence has been derived of the risk associated with combined communication of multiple events, and of the improvement in abnormal-environment safety that can be achieved through separate-event communication.
Date: December 1, 2003
Creator: Baty, Roy Stuart (Los Alamos National Laboratory, Los Alamos, NM); Johnston, Anna Marie; Hart, Elizabeth (Utah State University, Logan, UT); White, Allan (NASA, Langley Research Center, Hampton, VA) & Cooper, James Arlin
Partner: UNT Libraries Government Documents Department

China's Foreign Conventional Arms Acquisitions: Background and Analysis

Description: This report examines the major, foreign conventional weapon systems that China has acquired or has committed to acquire since 1990, with particular attention to implications for U.S. security concerns. It is not the assumption of this report that China’s military, the People’s Liberation Army (PLA), will engage in conflict with other forces in Asia. Nonetheless, since the mid-1990s, there has been increasing concern about China’s assertiveness in Asia and greater threats against Taiwan.
Date: November 6, 2001
Creator: Kan, Shirley A.; Bolkcom, Christopher & O'Rourke, Ronald
Partner: UNT Libraries Government Documents Department

China's Foreign Conventional Arms Acquisitions: Background and Analysis

Description: This report examines the major, foreign conventional weapon systems that China has acquired or has committed to acquire since 1990, with particular attention to implications for U.S. security concerns. It is not the assumption of this report that China’s military, the People’s Liberation Army (PLA), will engage in conflict with other forces in Asia. Nonetheless, since the mid-1990s, there has been increasing concern about China’s assertiveness in Asia and greater threats against Taiwan.
Date: October 10, 2000
Creator: Kan, Shirley A.; Bolkcom, Christopher & O'Rourke, Ronald
Partner: UNT Libraries Government Documents Department

Brazilian Trade Policy and the United States

Description: As the largest and one of the most influential countries in Latin America, Brazil has emerged as a leading voice for developing countries in setting regional and multilateral trade agendas. Brazil is critical of U.S. trade policies such as the Byrd Amendment (repealed, but program in effect until October 1, 2007), which directs duties from trade remedy cases to affected industries, the administration of trade remedy rules, and what it considers to be discriminatory treatment in the U.S. expansion of free trade agreements in Latin America. Despite the differences, both countries recognize the potential for important gains to be had from mutually acceptable trade liberalization at all levels.
Date: February 3, 2006
Creator: Hornbeck, J. F.
Partner: UNT Libraries Government Documents Department