Civil tiltrotor missions and applications. Phase 2: The commercial passenger market

The commercial passenger market for the civil tiltrotor was examined in phase 2. A market responsive commercial tiltrotor was found to be technically feasible, and a significant worldwide market potential was found to exist for such an aircraft, especially for relieving congestion in urban area-to-urban area service and for providing cost effective hub airport feeder service. Potential technical obstacles of community noise, vertiport area navigation, surveillance, and control, and the pilot/aircraft interface were determined to be surmountable. Nontechnical obstacles relating to national commitment and leadership and development of ground and air infrastructure were determined to be more difficult to resolve; an innovative public/private partnership is suggested to allow coordinated development of an initial commercial tiltrotor network to relieve congestion in the crowded US Northeast corridor by the year 2000

A coded aperture imaging system optimized for hard X-ray and gamma ray astronomy

A coded aperture imaging system was designed for the Gamma-Ray imaging spectrometer (GRIS). The system is optimized for imaging 511 keV positron-annihilation photons. For a galactic center 511-keV source strength of 0.001 sq/s, the source location accuracy is expected to be + or - 0.2 deg

Auswirkung der wiederholten antenatalen Kortikosteroidbehandlung auf das intrauterine Wachstum und auf die Grössenentwicklung imKleinkindesalter

Objective:The evaluation of the effects of repeated antenatal corticosteriod (CS) medication on birth size and size at the age of 4 years. Methods: 82 children exposed to CS initially between 26 and 28 weeks of gestation were matched with 82 controls of the same gestational age and sex. Results: No differences were observed between the CS and control groups with regard to weight, head circumference, and length at birth and at the age of 4 years. Conclusions: Our study failed to demonstrate that repetitive antenatal medication with CS in order to induce lung maturation has a negative im pact on intrauterine growth and growth in early childhood. Copyright (C) 2001 S. Karger AG, Basel

A new 147-56 hPa water vapor product from the UARS Microwave Limb Sounder

Measurements of H2O in the tropopause region have been obtained by production of a new data set from the Microwave Limb Sounder (MLS) on the Upper Atmosphere Research Satellite (UARS). A modified version of the retrieval scheme used to produce upper tropospheric humidity (UTH) from the MLS 203 GHz radiometer was applied to the MLS 183 GHz radiometer measurements to produce useful H2O data at 147, 121, 100, 83, 68, and 56 hPa. These new data, for the first 18 months of the UARS mission when the MLS 183 GHz radiometer was operational, fill an important “gap” around 100 hPa where previous MLS H2O data were generally not useful. Characteristics of the new data set are discussed and compared with National Oceanic and Atmospheric Administration (NOAA), Climate Monitoring and Diagnostics Laboratory (CMDL) frost-point hygrometer, and UARS Halogen Occultation Experiment (HALOE) measurements