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The purpose of this report is to evaluate and make recommendations concerning technologies that promise to improve the efilciency of compressed natural gas (CNG) light-duty vehicles. Technical targets for CNG automotive technology given in the March 1998 OffIce of Advanced Automotive Technologies research and development plan were used as guidance for this effort. The technical target that necessitates this current study is to validate technologies that enable CNG light vehicles to have at least 10% greater - fuel economy (on a miles per gallon equivalent basis) than equivalent gasoline vehicles by 2006. Other tar- gets important to natural gas (NG) automotive technology and this study are to: (1) increase CNG vehicle range to 380 miles, (2) reduce the incremental vehicle cost (CNG vs gasoline) to $1500, and (3) meet the California ultra low-emission vehicle (ULEV) and Federal Tier 2 emission standards expected to be in effect in 2004.

This report highlights important events and studies concerning surplus weapons-usable plutonium disposition in the United States. Included are major events that led to the creation of the U.S. Department of Energy (DOE) Office of Fissile Materials Disposition in 1994 and to that DOE office issuing the January 1997 Record of Decision for the Storage and Disposition of Weapons-Useable Fissile Materials Final Programmatic Environmental Impact Statement. Emphasis has been given to reactor-based plutonium disposition alternatives.

A 100 ns 8K /spl times/ 8 CMOS EPROM has been developed. Internal clock signals generated by address transition detection are used to reduce power consumption. As a result, power dissipation is less than 5 mW/MHz in the active mode, and less than 1 /spl mu/W in both the standby mode and the active quiescent mode (chip enabled, but no address transitions sensed). Three special test features incorporated in the design can be used to reduce the time required for final test and reliability screening.

A new yield function for compressible P M materials has been derived based upon a yield criterion postulated by the authors. This function was experimentally verified for the uniaxial state of compressive stress using the P M aluminum alloy X7091 as a model material, and excellent agreement was found between theoretical and experimental results for the density dependence of the yield and geometrical hardening. Yield surfaces for various density levels have been generated in a three-dimensional principal-stress space using computer graphics.