SIRTF science operations system

The Space Infrared Telescope Facility (SIRTF) will be launched in early 2003, and will perform an extended series of science observations at wavelengths ranging from 3.6 to 160 microns for five years or more. The California Institute of Technology has been selected as the home for the SIRTF Science Center (SSC). The SSC is completing the final stages of prelaunch development and testing of the Science Operations System (SOS), which will support science operations of the Observatory. The SOS supports a variety of functions including observing proposal submission by the scientific community, long range planning and short term scheduling of the Observatory, instrument performance monitoring during nominal operations, and production of a variety of scientific archival products. This paper describes the role and function of the SSC, the architecture of the SOS, and discusses the major SOS subsystems. Examples of products generated by the SOS are included

Breaking the cycle? The effect of education on welfare receipt among children of welfare recipients

We examine the impact of high school graduation on the probability individuals from welfare backgrounds use welfare themselves. Our data consists of administrative educational records for grade 12 students in a Canadian province linked with their own and their parents' welfare records. We address potential endogeneity problems by: 1) controlling for ability using past test scores; 2) using an instrument for graduation based on school principal fixed effects; and 3) using a Heckman- Singer type unobserved heterogeneity estimator. Graduation would reduce welfare receipt of dropoutsby Ý to 3/4. Effects are larger for individuals from troubled family backgrounds and low income neighbourhoods.

Multimission image processing and science data visualization

The Operational Science Analysis (OSA) Functional area supports science instrument data display, analysis, visualization and photo processing in support of flight operations of planetary spacecraft managed by the Jet Propulsion Laboratory (JPL). This paper describes the data products generated by the OSA functional area, and the current computer system used to generate these data products. The objectives on a system upgrade now in process are described. The design approach to development of the new system are reviewed, including use of the Unix operating system and X-Window display standards to provide platform independence, portability, and modularity within the new system, is reviewed. The new system should provide a modular and scaleable capability supporting a variety of future missions at JPL

Use of a multimission system for cost effective support of planetary science data processing

JPL's Multimission Operations Systems Office (MOSO) provides a multimission facility at JPL for processing science instrument data from NASA's planetary missions. This facility, the Multimission Image Processing System (MIPS), is developed and maintained by MOSO to meet requirements that span the NASA family of planetary missions. Although the word 'image' appears in the title, MIPS is used to process instrument data from a variety of science instruments. This paper describes the design of a new system architecture now being implemented within the MIPS to support future planetary mission activities at significantly reduced operations and maintenance cost

Constitutional Law

Covers cases on dams and waterpower—eminent domain—interstate commerce—municipal corporations—res judicata—state officers—the Cowlitz Dam Case (Stoebuck) and on treaties with Indians—fishing rights (Green)

Digital Processing of Remotely Sensed Imagery

Digital images can be acquired from various devices. Image scanners on personal computers can generate digital images of hard copy material. New digital cameras operate without film, recording a digital image of the scene in local solid state memory. Remote sensing instruments routinely return digital imagery to receiving stations for processing and display. Digital processing of remotely sensed imagery is a technology that is now over thirty years old. Earth orbitting and deep space exploration spacecraft have been returning digital imagery for many years. Earth-based systems, including biomedical imaging devices and other commercially available types of equipment, have also been producing digital imagery for many years. Each of these devices produce a digital version of an image as a two dimensional array of numbers. The values in the matrix represent the brightness of the scene at each individual sampled position in the image

SIRTF science operations system

The Space Infrared Telescope Facility (SIRTF) will be launched in early 2003, and will perform an extended series of science observations at wavelengths ranging from 3.6 to 160 microns for five years or more. The California Institute of Technology has been selected as the home for the SIRTF Science Center (SSC). The SSC is completing the final stages of prelaunch development and testing of the Science Operations System (SOS), which will support science operations of the Observatory. The SOS supports a variety of functions including observing proposal submission by the scientific community, long range planning and short term scheduling of the Observatory, instrument performance monitoring during nominal operations, and production of a variety of scientific archival products. This paper describes the role and function of the SSC, the architecture of the SOS, and discusses the major SOS subsystems. Examples of products generated by the SOS are included

Contributors to the May Issue/Notes

Notes by William B. Lawless, Timothy M. Green, Thomas J. Mitchell, John D. Ryan, Charles Boynton, John R. Baty, and Theodore P. Frericks

Određivanje dužine korijenskog kanala: procjena CDR® intraoralnog radiografskog sustava in vivo

The Computed Dental Radiolography System® (CDR: Schick Technologies, Long Island City, NY) is a CCD-based digital intraoral radiographic device which possesses a measurement software algorithm that can be adjusted with respect to an object of known dimension. This “calibration ” algorithm was compared to the CDR® preset mode and analog film using 30 root canals in vivo. The three measurement methods differed significantly from each other for 40% o f the canals sampled. Two o f the three differed significantly for 50% o f canals. No difference existed between the methods for 10% o f the canals. Estimates of tooth length using the calibrated mode differed from those obtained using a conventional radiographic technique by an average o f 1.2 mm, while those using the calibrated mode differed by 1.9 mm. The 1.2 mm average for the calibrated CDR® was judged to be an acceptable degree o f clinical error for most root canal procedures and indicates that the calibration function of the CDR® system should be used when measuring endodontic working lengths. The results demonstrated that calibration to a 15 mm probe when using the Schick CDR® system is more consistent with a comparable measurement, if film is used as the “gold standard”, than are measurements of the tooth length using the CDR® without calibration.Sustav "Kompjuterizirane dentalne radiografije" (CDR: Schick Technologies. Long Island City. NY) je na CDD-u zasnovan uređaj za digitalnu intraoralnu radio grafiju koji posjeduje "Software-ski algoritam" za mjerenja koji se može prilagoditi prema objektu poznate veličine. Ovaj "kalibracijski" algoritam uspoređen je sa sustavom CDR (kompjutorizirane dentalne radiografije) bez mjernog algoritma i analognim filmom rabeći 30 korijenskih kanala in vivo. Tri postupka mjerenja značajno su se razlikovali u 40% mjerenih korijenskih kanala. Dva od tri postupka razlikovala su se u 50% mjerenih kanala. Nikakve razlike između postupaka nije bilo u 10% mjerenih korijenskih kanala. Procjena duljine zuba korištenjem kalibriranog načina razlikovala se od procjene dobivene konvencionalnom (analognom) radio grafskom tehnikom za otprilike 1,2 mm, dok se od digitalnog sustava bez mjernog algoritma razlikovala za prosječno 1,9 mm. Razlika od 1,2 mm za "kalibrirani CDR" se procjenjuje kao prihvatljiva klinička greška za većinu endodontskih postupaka i ukazuje da bi se "kalibracijski sustav CDRa" trebao rabiti pri mjerenju radne duljine korijenskog kanala. Rezultati ukazuju da je kalibracija sonde do 15 mm kad se rabi Schch-ov CDR sustav postojanija s usporednim mjerenjem ako se film koji se mjeri uzme kao "zlatni standard", nego je mjerenje duljine CDR sustavom bez kalibracije