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101.
NASA Langley Research Center (LaRC) began using the World Wide Web (WWW) in the summer of 1993, becoming the first NASA installation to provide a center-wide home page. This coincided with a reorganization of LaRC to provide a more concentrated focus on technology transfer to both aerospace and non-aerospace industry. Use of WWW and NCSA Mosaic not only provides automated information dissemination, but also allows for the implementation, evolution and integration of many technology transfer and technology awareness applications. This paper describes several of these innovative applications, including the on-line presentation of the entire Technology Opportunities Showcase (TOPS), an industrial partnering showcase that exists on the Web long after the actual 3-day event ended. The NASA Technical Report Server (NTRS) provides uniform access to many logically similar, yet physically distributed NASA report servers. WWW is also the foundation of the Langley Software Server (LSS), an experimental software distribution system which will distribute LaRC-developed software. In addition to the more formal technology distribution projects, WWW has been successful in connecting people with technologies and people with other people  相似文献   
102.
103.
The development of the new CIRA will require the combination of winds from many sources, e.g. rockets (ROCOB) up to ~60 km, and radar winds ~60–110 km. Difficulties are that such rocket data have larger errors at 60–65 km, and tidal effects may become significant. Radar data for 60–80 km may also have tidal contamination, due to ? 16h of data per day: from 80–110 km tidal corrections are usually reliable.Comparisons are made between the unique Saskatoon MF radar set, which is continuous from mid 1978–1983, and the ROCOB data from Primrose Lake, which is only 340 km northwest. While the agreement is satisfactory, special care is required when matching the two regions: particular problems are the low rocket sampling rate, and the unexpectedly large amplitude of the diurnal tide. Important differences from the zonal winds of CIRA-72 emerge, especially in winter months. Meridional cross-sections differ from previous data models in the extent of the summer equatorward flow.  相似文献   
104.
This work is devoted to the derivation of the optical properties of the Venus atmosphere from “Venera-10” optical measurements. Within the framework of a two-layer model of Venus atmosphere it is found that in the spectral interval 0.52 – 0.85 μm the optical thickness of the upper cloud layer is ≈ 50 and the optical parameters of the lower layer are similar to the Rayleigh ones. Comparison is made between the measurements of radiation field within the atmosphere and the results of strict calculations. A preliminary conclusion is suggested that there are considerable numbers of aerosol particles with a radius ? 0.03 μm in the lower layer. The results of the upper boundary of the cloud layer is estimated to be ≈ 70 km.  相似文献   
105.
The LIMS experiment was launched on the Nimbus 7 satellite for the purpose of sounding the vertical structure of temperature and key upper atmosphere trace gases on a global scale. The technique of thermal infrared limb sounding was used to obtain measurements of O3, H2O, NO2, and HNO3. LIMS collected data almost continuously from late October to late May over the latitude range from 64°S to 84°N. Two of the gases, NO2 and HNO3, are important elements in the NOx chain of chemical reactions leading to ozone destruction. We will describe results for these gases in terms of zonal mean profiles and latitudinal distributions. The period selected for study is January–May 1979, when a major stratospheric warming occurred.  相似文献   
106.
107.
The presence of compact X-ray sources in globular clusters allows diagnostic studies of both the X-ray sources themselves and the globular clusters to be carried out. A review of much of this work, primarily based on Einstein X-ray observations and supporting studies of globular clusters at radio through UV wavelengths, is presented. The compact X-ray sources in globular clusters are found to be compact binaries containing neutron stars and - in a separate lower luminosity component of an apparently bimodal luminosity function - possibly white dwarfs. Implications for the formation and evolution of compact binary X-ray sources in globular clusters and in the galactic bulge are discussed. In particular, new evidence is presented that the galactic bulge sources may be compact binaries in the remnants of disrupted globular clusters.  相似文献   
108.
Rockwool, as an inert medium covered or bagged with polyethylene film, can be effectively used for plant culture in space station. The most important machine is the pump adjusting the dripping rate in the feeding system. Hydro-aeroponics may be adaptable to a space laboratory. The shortening of the light-dark cycles inhibits plant growth and induces an abnormal morphogenesis. A photoperiod of 12-hr-dark may be needed for plant growth.  相似文献   
109.
Hydrogenated amorphous Si (a-Si:H) devices first made a significant impact in photovoltaic application, 70% of the photovoltaic solar cells produced in Japan in 1984 were a-Si:H. More recently, thin film transistor (TFT) and sensor devices have been developed for consumer and business products. The ability to produce large area uniform films of a-Si:H makes the application of TFTs and sensors well suited for input and output imaging devices such as image scanners, display and printers. This paper reviews the operation, material issues and physics of a-Si:H TFTs and sensors. The circuit and technology issues in large area systems incorporating these devices are described.  相似文献   
110.
EXOSAT observations of the dwarf nova VW Hydri reveal a strong soft X-ray flux during optical superoutburst. The onset of the X-ray outburst was delayed by 2.5 days compared to the optical outburst. A modulation of the extreme soft X-ray flux was detected, consistent with a coherent (0 >x 107) pulsation with a period of 14.07 seconds, probably reflecting the rotation period of the white dwarf.IIf this is indeed the case, VW Hydri is the fastest rotating white dwarf detected so far.  相似文献   
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