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A Cobit primer

Campbell, Philip L.

COBIT is a set of documents that provides guidance for computer security. This report introduces COBIT by answering the following questions, after first defining acronyms and presenting definitions: 1. Why is COBIT valuable? 2. What is COBIT?, and 3. What documents are related to COBIT? (The answer to the last question constitutes the bulk of this report.) This report also provides more detailed review of three documents. The first two documents--COBIT Security Baseline{trademark} and COBIT Quickstart{trademark}--are initial documents, designed to get people started. The third document-Control Practices-is a ''final'' document, so to speak, designed to take people all the way down into the details. Control Practices is the detail.

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TYPE SAND Report YEAR 2005
DOIOSTI

Status of the Z Refurbishment project (ZR) at Sandia National Laboratories

Bloomquist, Douglas D.; McDaniel, Dillon H.; Weed, John W.; Faturos, Thomas V.; Mckee, G.R.; Tabor, Debra; Warner, Peggy J.

Sandia National Laboratories Z Refurbishment (ZR) Project formally began in August 2002 to increase the Z Accelerator's utilization by providing the capability to perform more shots, improve precision and pulse shape variability, increase delivered current, and accomplish the improvements with minimal disruption to Z's ongoing programs. A project overview was provided at the 14th International Pulsed Power Conference in 2003. This paper provides an update of the project including architectural changes over the past two years, timeframe for completion, and overall design and fabrication status.

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TYPE Conference YEAR 2005
OSTI

Thermodynamic and structural characterization of Mg-Li-N-H storage system

Proposed for publication in the Journal of Alloys and Compounds.

Sickafoose, Shane

The Mg-Li-N-H system is a very promising hydrogen storage material due to its high capacity, reversibility and moderate operating conditions. Some of thermodynamic and structural properties for this system are characterized here. Pressure-composition isotherms are measured and presented in this paper for absorption-desorption at 220, 200 and 180 C. Powder X-ray diffraction (XRD) and Fourier Transform Infrared (FTIR) analysis were carried out for samples at various degrees of hydrogenation. These results provide information about the structural changes during absorption/desorption. The mixture of (2LiNH{sub 2} + MgH{sub 2}) partially converts to (Mg(NH{sub 2}){sub 2} + 2LiH) when heated at 220 C and 100 bar of hydrogen without undergoing desorption. Based on two distinct parts which appear in all of the pressure-composition isotherms (180-220 C), two reactions taking place isothermally in hydrogen absorption/desorption are proposed for the material starting with (2LiNH{sub 2} + MgH{sub 2}) or (Mg(NH{sub 2}){sub 2} + 2LiH). These reactions include a single solid-phase reaction, corresponding to the sloping region for hydrogen weight percent (Hwt%) smaller than 1.5%, and a multiple-phase reaction, corresponding to a plateau region for Hwt.% > 1.5 in the isotherms. During hydrogen absorption/desorption, the single-solid-phase reaction corresponds to the forming/consuming of NH{sub 2} which is bonded to Li and the multiple-solid-phase reaction corresponds to forming/consuming Mg(NH{sub 2}){sub 2} and LiH. A mechanism for the sorption reactions has been proposed.

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TYPE Journal Article YEAR 2005
OSTI
Results 86151–86175 of 99,299
Results 86151–86175 of 99,299