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Smith, J. H.

Publications and source records attributed to Smith, J. H..

30 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS1982

Cloud cover estimation: Use of GOES imagery in development of cloud cover data base for insolation assessment

The potential of using digital satellite data to establish a cloud cover data base for the United States, one that would provide detailed information on the temporal and spatial variability of cloud development are studied. Key elements include: (1) interfacing GOES data from the University of Wisconsin Meteorological Data Facility with the Jet Propulsion Laboratory's VICAR image processing system and IBIS geographic information system; (2) creation of a registered multitemporal GOES data base; (3) development of a simple normalization model to compensate for sun angle; (4) creation of a variable size georeference grid that provides detailed cloud information in selected areas and summarized information in other areas; and (5) development of a cloud/shadow model which details the percentage of each grid cell that is cloud and shadow covered, and the percentage of cloud or shadow opacity. In addition, comparison of model calculations of insolation with measured values at selected test sites was accomplished, as well as development of preliminary requirements for a large scale data base of cloud cover statistics.

Huning, J. R.↗
NASA NTRS1982

Update on a system for large area crop inventory from remotely sensed data

In connection with the conduction of the Large Area Crop Inventory Experiment (LACIE), a state-of-the-art technology for the inventory of crops using satellite data was developed and tested over a period of three years (1975-77). A method was obtained for determining the total wheat production in a given region by looking at only a subset of its area. The present investigation is concerned with the current state of the art as obtained in the aggregation technology of the Agriculture and Resources Inventory Surveys Through Aerospace Remote Sensing (AgRISTARS) program. Attention is given to details of AgRISTARS baseline aggregation technology, and to recent improvements and future research directions.

Baker, T. C.↗
NASA NTRS1982

Acquisition history simulation for evaluation of Landsat-based crop inventory systems

This paper describes the development and evaluation of a simulation procedure which produces patterns of Landsat data loss attributable to cloud patterns that are characteristic of a crop region. This simulation procedure is part of a simulation system under development which evaluates the performance of crop inventory system components over a number of years and under a variety of conditions.

Smith, J. H.↗
NASA NTRS1981

Fiscal year 1981 US corn and soybeans pilot preliminary experiment plan, phase 1

A draft of the preliminary experiment plan for the foreign commodity production forecasting project fiscal year 1981 is presented. This draft plan includes: definition of the phase 1 and 2 U.S. pilot objectives; the proposed experiment design to evaluate crop calendar, area estimation, and area aggregation components for corn and soybean technologies using 1978/1979 crop-year data; a description of individual sensitivity evaluations of the baseline corn and soybean segment classification procedure; and technology and data assessment in support of the corn and soybean estimation technology for use in the U.S. central corn belt.

Livingston, G. P.↗
NASA NTRS1981

Urban air pollution and solar energy

The design and performance of solar energy systems for many potential applications (industrial/residential heat, electricity generation by solar concentration and photovoltaics) will be critically affected by local insolation conditions. The effects of urban air pollution are considered and reviewed. A study of insolation data for Alhambra, California (9 km south of Pasadena) shows that, during a recent second-stage photochemical smog alert (greater than or equal to 0.35 ppm ozone), the direct-beam insolation at solar noon was reduced by 40%, and the total global by 15%, from clean air values. Similar effects have been observed in Pasadena, and are attributable primarily to air pollution. Effects due to advecting smog have been detected 200 km away, in the Mojave Desert. Preliminary performance and economic simulations of solar thermal and photovoltaic power systems indicate increasing nonlinear sensitivity of life cycle plant cost to reductions in insolation levels due to pollution.

Gammon, R. B.↗
NASA NTRS1981

Predesign study for a modern 4-bladed rotor for the NASA rotor systems research aircraft

Trade-off study results and the rationale for the final selection of an existing modern four-bladed rotor system that can be adapted for installation on the Rotor Systems Research Aircraft (RSRA) are reported. The results of the detailed integration studies, parameter change studies, and instrumentation studies and the recommended plan for development and qualification of the rotor system is also given. Its parameter variants, integration on the RSRA, and support of ground and flight test programs are also discussed.

Bishop, H. E.↗
NASA NTRS1980

Solar insolation model

Computer program SOLINS helps engineers with relatively complex task of choosing best orientation of fixed flat-plate solar collectors for local conditions. Program models average hourly solar insolation on fixed but arbitrarily-oriented surface. Consideration is given to problems of array spacing, shadowing, and use of augmentation reflectors to increase insolation at collector surface.

Smith, J. H.↗
NASA NTRS1973

Prediction of explosive yield and other characteristics of liquid rocket propellant explosions

Work which has been done at the University of Florida in arriving at credible explosive yield values for liquid rocket propellants is presented. The results are based upon logical methods which have been well worked out theoretically and verified through experimental procedures. Three independent methods to predict explosive yield values for liquid rocket propellants are described. All three give the same end result even though they utilize different parameters and procedures. They are: (1) mathematical model; (2) seven chart approach; and (3) critical mass method. A brief description of the methods, how they were derived, how they were applied, and the results which they produced are given. The experimental work used to support and verify the above methods both in the laboratory and in the field with actually explosive mixtures are presented. The methods developed are used and their value demonstrated in analyzing real problems, among them the destruct system of the Saturn 5, and the early configurations of the space shuttle.

Farber, E. A.↗