The SAAM architecture : enabling integrated services

Computer networks of today are based predominantly on the TCP/IP protocol suite that provides best effort service. The current IP protocol excels in its simplicity and network fault tolerance. The way it implements this simplicity and fault tolerance, however, limits the protocol's ability to provide a guaranteed Quality of Service (QoS). A first Step in providing this QoS is to incorporate the concept of flow based routing. This thesis describes an implementation of the Server and Agent based Active network Management (SAAM) system architecture that incorporates flow based routing. The architecture contains servers that maintain a database that is used for assigning each flow to a path that will provide the needed QoS.http://archive.org/details/thesaamrchitectu1094539420U.S. Marine Corps (U.S.M.C.) authorsApproved for public release; distribution is unlimited

Investigating Hydrogen-Bonded Phosphonic Acids with Proton Ultrafast MAS NMR and DFT Calculations

Hydrogen-bonding plays a key role in the structure and dynamics of a wide range of materials from small molecules to complex biomolecules. ¹H NMR has emerged as a powerful tool for studying hydrogen-bonding because the proton isotropic chemical shift exhibits a dependence on the interatomic distances associated with the hydrogen bond. In the present work, we illustrate the use of ultrafast magic angle spinning at high magnetic field (800 MHz) for resolving multiple hydrogen-bonding sites in a set of crystalline phosphonic acids that contain various functional groups (−COOH, −PO₃H₂, and −NH₃⁺). Trends are observed between the proton chemical shift of the hydrogen-bonded proton and the associated hydrogen-bonding distances (O–H···X) from X-ray crystallography. Density functional theory calculations conducted on the phosphonic acid structures illustrate that the experimental proton chemical shift dependence on hydrogen-bond distance agrees with the expected theoretical trends. Further, it is shown that the chemical shift trend varies considerably depending on the functional group participating in the hydrogen bonding, albeit a −COOH, −PO₃H₂, or −NH₃⁺ moiety. An improved understanding of these trends for various functional groups should be useful for determining accurate hydrogen-bond strengths from the proton chemical shift in an array of systems

The First Data Release of the Sloan Digital Sky Survey

The Sloan Digital Sky Survey (SDSS) has validated and made publicly available its First Data Release. This consists of 2099 deg2 of five-band (u, g, r, i, z) imaging data, 186,240 spectra of galaxies, quasars, stars and calibrating blank sky patches selected over 1360 deg2 of this area, and tables of measured parameters from these data. The imaging data go to a depth of r ≈ 22.6 and are photometrically and astrometrically calibrated to 2% rms and 100 mas rms per coordinate, respectively. The spectra cover the range 3800–9200 Å, with a resolution of 1800–2100. This paper describes the characteristics of the data with emphasis on improvements since the release of commissioning data (the SDSS Early Data Release) and serves as a pointer to extensive published and on-line documentation of the survey.Astronom

SEGUE : a spectroscopic survey of 240,000 stars with g=14-20

The Sloan Extension for Galactic Understanding and Exploration (SEGUE) Survey obtained approximate to 240,000 moderate-resolution (R similar to 1800) spectra from 3900 angstrom to 9000 angstrom of fainter Milky Way stars (14.0 10 per resolution element, stellar atmospheric parameters are estimated, including metallicity, surface gravity, and effective temperature. SEGUE obtained 3500 deg(2) of additional ugriz imaging (primarily at low Galactic latitudes) providing precise multicolor photometry (sigma(g, r, i) similar to 2%), (sigma(u, z) similar to 3%) and astrometry (approximate to 0 ''.1) for spectroscopic target selection. The stellar spectra, imaging data, and derived parameter catalogs for this survey are publicly available as part of Sloan Digital Sky Survey Data Release 7