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High-performance transaction system applications typically insert rows in a History table to provide an activity trace; at the same time the transaction system generates log records for purposes of system recovery. Both types of generated information can benefit from efficient indexing. An example in a well-known setting is the TPC-A benchmark application,(More)
(NASA/GSFC) is responsible for the design, development, and operation of the Cosmic Background Explorer (COBE). Scientific guidance is provided by the COBE Science Working Group. GSFC is also responsible for the development of the analysis software and for the production of the mission data sets. ABSTRACT We have refined the analysis of the data from the(More)
We report on the characteristics and design details of the Medium Scale Anisotropy Measurement (MSAM), a millimeter-wave, balloon-borne telescope that has been used to observe anisotropy in the Cosmic Microwave Background Radiation (CMBR) on 0. • 5 angular scales. The gondola is capable of determining and maintaining absolute orientation to a few arcminutes(More)
The Advanced Camera for the Hubble Space Telescope has three cameras. The first, the Wide Field Camera, will be a high-throughput (44% at 600 nm, including the HST OTA), wide field (200"×204"), 4096 × 4096 pixel CCD optical and I-band camera that is half-critically sampled at 500 nm. The second, the High Resolution Camera (HRC), is a 1024 × 1024 pixel CCD(More)
The Microwave Anisotropy Probe and Planck missions will provide low noise maps of the temperature of the cosmic microwave background (CMB). These maps will allow measurement of the power spectrum of the CMB with measurement noise below cosmic variance for ℓ < 1500. It is anticipated that no further all sky CMB temperature observations will be needed after(More)
The second flight of the Medium Scale Anisotropy Measurement (MSAM1-94) observed the same field as the first flight (MSAM1-92) to confirm our earlier measurement of cosmic microwave background radiation (CMBR) anisotropy. This instrument chops a 30 ′ beam in a 3 position pattern with a throw of ±40 ′ , and simultaneously measures single and double(More)
The Spectral Energy Distribution (SPEED) Camera is being developed to study the spectral energy distributions of high redshift galaxies. Its initial use will be on the Heinrich Hertz Telescope and eventually on the Large Millimeter Telescope. SPEED requires a small cryogenic detector array of 2 Â 2 pixels with each pixel having four frequency bands in the(More)
This paper presents a description of the Hubble Space Telescope (HST) Near Infrared Camera and Multi Object Spectrometer (NICMOS) Cooling System (NCS), the evolution of the cutting edge technology involved, a comparison of predicted versus on-orbit thermal performance, as well as possible future space applications. The NCS hardware consists of the NICMOS(More)
We present new cosmic microwave background (CMB) anisotropy results from the combined analysis of the three flights of the first Medium Scale Anisotropy Measurement (MSAM1). This balloon-borne bolo-metric instrument measured about 10 square degrees of sky at half-degree resolution in 4 frequency bands from 5.2 cm −1 to 20 cm −1 with a high signal-to-noise(More)
In many cosmological models, the large angular scale anisotropy in the cosmic microwave background is parameterized by a spectral index, n, and a quadrupolar amplitude, Q. For a Peebles-Harrison-Zel'dovich spectrum, n = 1. Using data from the Far Infra-Red Survey (FIRS) and a new statistical measure, a contour plot of the likelihood for cosmological models(More)