Download or read book Satellite Density Measurements with the Rotatable Calibration Accelerometer ROCA written by Frank A. Marcos and published by . This book was released on 1979 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Satellite accelerometer measurements of atmospheric density have provided significant improvement in our understanding of the structure and dynamics of the lower thermosphere. Derivation of accurate data with this technique requires removal of instrument bias from the total sensor output. The ROCA (Rotatable Calibration Accelerometer) experiment was flown to provide and orbital calibration capability on the three-axis stabilized S3-4 satellite. The ROCA sensitive axis could be operated in either of two orientations selectable by ground command. For density measurement (normal operating mode) the sensitive axis was aligned with the satellite velocity vector. For direct measurement of bias, the sensitive axis was aligned perpendicular to the velocity vector. Utilization of the inflight calibration technique showed a dependence of the bias upon the instrument operating temperature. Removal of the bias-temperature component from the total acceleration signal obtained in the normal operating mode permits derivation of accurate density data. Measurements of atmospheric density were obtained during approximately 600 orbits over a five month period. The resulting ROCA data will be utilized for improved satellite ephemeris computations and for detailed studies of the lower thermosphere, particularly those related to energy inputs at high latitudes. (Author).
Download or read book Satellite Density Measurements with the Rotatable Calibration Accelerometer ROCA written by Frank A. Marcos and published by . This book was released on 1979 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Satellite accelerometer measurements of atmospheric density have provided significant improvement in our understanding of the structure and dynamics of the lower thermosphere. Derivation of accurate data with this technique requires removal of instrument bias from the total sensor output. The ROCA (Rotatable Calibration Accelerometer) experiment was flown to provide and orbital calibration capability on the three-axis stabilized S3-4 satellite. The ROCA sensitive axis could be operated in either of two orientations selectable by ground command. For density measurement (normal operating mode) the sensitive axis was aligned with the satellite velocity vector. For direct measurement of bias, the sensitive axis was aligned perpendicular to the velocity vector. Utilization of the inflight calibration technique showed a dependence of the bias upon the instrument operating temperature. Removal of the bias-temperature component from the total acceleration signal obtained in the normal operating mode permits derivation of accurate density data. Measurements of atmospheric density were obtained during approximately 600 orbits over a five month period. The resulting ROCA data will be utilized for improved satellite ephemeris computations and for detailed studies of the lower thermosphere, particularly those related to energy inputs at high latitudes. (Author)
Download or read book A Global Thermospheric Density Model Based on Satellite Accelerometer Data written by Frank A. Marcos and published by . This book was released on 1982 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Application of the Satellite Triaxial Accelerometer Experiment to Atmospheric Density and Wind Studies written by Frank A. Marcos and published by . This book was released on 1982 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: A new satellite triaxial accelerometer system has been developed. This instrument has been flight-tested on three-axis stabilized satellites and has demonstrated the capability to accurately measure accelerations in the satellite's in-track, cross-track, and radial directions. The in-track data provide direct determination of atmospheric density. These data, obtained during a period of high solar flux, supplement the extensive set of measurements obtained by other accelerometer experiments during low solar flux conditions. The cross-track and radial results permit, for the first time, large-scale measurements of the zonal and, possibly, radial components of neutral atmospheric winds. These simultaneous wind and density data provide an extremely valuable input for the understanding of dynamic processes in the atmosphere and for the improvement of atmospheric models.
Download or read book Satellite Atmospheric Radiance Measurements in the Vacuum Ultraviolet written by Robert E. Huffman and published by . This book was released on 1979 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: A satellite experiment has obtained nadir-viewing atmospheric radiance measurements in the 1100 to 2900 angstrom wavelength region from the polar orbiting satellite S3-4. This report describes the instrumentation, measurement techniques, and initial results. The observed emission is from airglow, solar scatter, and auroral regions. Spectral and spatial measurements previously unavailable have been made for the nitrogen Lyman-Birge-Hopfield emission, vacuum ultraviolet aurora, hydrogen geocorona, tropical ultraviolet airglow, twilight fluorescence nitric oxide spectrum, and night oxygen Herzberg band emission. Low values of the day and night background radiance values have been found; these values can be applied to improved missile detection techniques. Spatial resolution down to about one kilometer will enable possible variability to be sought. Observations were made in the period March to September 1978. Correlations with other geophysical factors such as solar flux, magnetic index, and seasonal variations will be made after the data base from the experiment is completed.
Download or read book Instrumentation Papers written by and published by . This book was released on 1978 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1980 with total page 760 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book Application of Satellite Accelerometer Data to Improve Density Models written by Frank A. Marcos and published by . This book was released on 1984 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: Atmospheric density measurements obtained by the satellite accelerometer experiment provide data over a wide range of solar and geophysical conditions. These results are used in a preliminary evaluation of several atmospheric models. The model accuracies are compared by their mean values and standard deviations relative to the accelerometer data. Sources of model uncertainties and problems in reducing them are described. Long-term programs involving coordinated measurements, analyses of available data and theoretical studies are required along with development of more accurate indicators of solar and geomagnetic activity before models can show significant improvement. Keywords include: Satellite, Accelerometers, Atmospheric density measurements, Thermospheric model evaluations, Thermospheric density variability.
Download or read book Government Reports Announcements Index written by and published by . This book was released on 1979 with total page 1182 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book R D Abstracts written by Technology Reports Centre (Great Britain) and published by . This book was released on 1980 with total page 554 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Technical Abstract Bulletin written by and published by . This book was released on 1979 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Meteorological and Geoastrophysical Abstracts written by and published by . This book was released on 1979 with total page 1382 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Annual Index written by and published by . This book was released on 1979 with total page 1032 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sections 1-2. Keyword Index.--Section 3. Personal author index.--Section 4. Corporate author index.-- Section 5. Contract/grant number index, NTIS order/report number index 1-E.--Section 6. NTIS order/report number index F-Z.
Download or read book Government Reports Annual Index Keyword A L written by and published by . This book was released on 1979 with total page 840 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Peacebuilding Tool for a Conflict Sensitive Approach to Development written by Asian Development Bank and published by Asian Development Bank. This book was released on 2012-03-01 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Asian Development Bank (ADB) works with a number of developing member countries facing fragile and conflict-affected situations---circumstances that complicate economic development, and might include domestic or international conflict, ethnic tensions, vulnerability to natural disasters, or a confluence of these factors. ADB piloted the peacebuilding tool in Nepal as a conflict-sensitive approach, a key to effective and safe implementation of projects in the country's post-conflict context. The peacebuilding tool is an analytical tool for assisting project team leaders and social experts in understanding the local context, and in identifying potential risks to implementation of development projects that are linked to social conflicts, as well as in formulating mitigation measures for addressing these risks.
Download or read book Precise Geodetic Infrastructure written by National Research Council and published by National Academies Press. This book was released on 2010-10-25 with total page 157 pages. Available in PDF, EPUB and Kindle. Book excerpt: Geodesy is the science of accurately measuring and understanding three fundamental properties of Earth: its geometric shape, its orientation in space, and its gravity field, as well as the changes of these properties with time. Over the past half century, the United States, in cooperation with international partners, has led the development of geodetic techniques and instrumentation. Geodetic observing systems provide a significant benefit to society in a wide array of military, research, civil, and commercial areas, including sea level change monitoring, autonomous navigation, tighter low flying routes for strategic aircraft, precision agriculture, civil surveying, earthquake monitoring, forest structural mapping and biomass estimation, and improved floodplain mapping. Recognizing the growing reliance of a wide range of scientific and societal endeavors on infrastructure for precise geodesy, and recognizing geodetic infrastructure as a shared national resource, this book provides an independent assessment of the benefits provided by geodetic observations and networks, as well as a plan for the future development and support of the infrastructure needed to meet the demand for increasingly greater precision. Precise Geodetic Infrastructure makes a series of focused recommendations for upgrading and improving specific elements of the infrastructure, for enhancing the role of the United States in international geodetic services, for evaluating the requirements for a geodetic workforce for the coming decades, and for providing national coordination and advocacy for the various agencies and organizations that contribute to the geodetic infrastructure.
Download or read book Solar Cells and Modules written by Arvind Shah and published by Springer Nature. This book was released on 2020-07-16 with total page 357 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book gives a comprehensive introduction to the field of photovoltaic (PV) solar cells and modules. In thirteen chapters, it addresses a wide range of topics including the spectrum of light received by PV devices, the basic functioning of a solar cell, and the physical factors limiting the efficiency of solar cells. It places particular emphasis on crystalline silicon solar cells and modules, which constitute today more than 90 % of all modules sold worldwide. Describing in great detail both the manufacturing process and resulting module performance, the book also touches on the newest developments in this sector, such as Tunnel Oxide Passivated Contact (TOPCON) and heterojunction modules, while dedicating a major chapter to general questions of module design and fabrication. Overall, it presents the essential theoretical and practical concepts of PV solar cells and modules in an easy-to-understand manner and discusses current challenges facing the global research and development community.
