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Alexander, R. H.

Publications and source records attributed to Alexander, R. H..

27 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS1973

ERTS regional scale overview linking land use and environmental processes in CARETS

A mosaic of ERTS images of the CARETS region has been used to partition the region into zones on the basis of similarity of tones and textures visible at a regional-scale overview. The resulting patterns were compared with existing small scale maps of the region representing relief, land surface forms, geology, soils, vegetation, forest types, and land use. The ERTS-derived zones most closely resemble the patterns on the small scale land use map, suggesting that, at least in a highly developed region such as CARETS, land use is an indicator or resultant surface expression of several interacting environmental processes. These results lend support to the CARETS model of interdisciplinary regional analysis, whereby remote sensor-derived data sets on land use and land use change become the basic data entry into a regional information system to serve regional planners and land managers.

Alexander, R. H.↗
NASA NTRS1972

Central Atlantic regional ecological test site: A prototype regional environmental information system

The author has identified the following significant results. Preliminary analysis of the capabilities of ERTS-1 data in land use mapping and change detection has revealed that Level 1 land use mapping can be performed and that in some cases land use changes can be identified. Land use interpretation was accomplished with the aid of a film projection viewer and the I2S additive color viewer. By varying the filters and illumination of each spectral band it was possible to better distinguish urban areas and transportation routes. Also it enabled the toning down of signatures such as cropland and forests which on many color infrared composite photographs were washed out with strong red tints. It appears that ERTS-1 imagery is useful not only for Level 1 mapping at scales of 1:250,000 or smaller, but also for monitoring agricultural changes and locating areas of construction, when such land uses approach an area of approximately two hectares.

Alexander, R. H.↗
NASA NTRS1972

Central Atlantic regional ecological test site: A prototype regional environment information system

The author has identified the following significant results. Prior to the actual testing of data from ERTS-1, the principal scientific results to date are the establishment of a model or design for a regional land use information system based on remote sensor data and a firm establishment of the RB-57 type high altitude aircraft data base as an important tool in land use mapping. Preliminary user evaluations of the resulting land use data have been favorable, and one of the states, Maryland, has adopted the USGS-GAP land use system as a first step towards mapping their entire state. The State is funding an extension (to the west) of the part of Maryland not covered by CARETS (Central Atlantic Regional Ecological Test Site), using the GAP land use classification and mapping procedures.

Alexander, R. H.↗
NASA NTRS1972

Central Atlantic regional ecological test site

The work of the Central Atlantic Regional Ecological Test Site (CARETS) project is discussed. The primary aim of CARETS is to test the hypothesis that data from ERTS-A can be made an integral part of a regional land resources information system, encompassing both inventory of the resource base and monitoring of changes, along with their effects on the quality of the environment. Another objective of the project is to determine scaling factors for developing land use information and regional analysis for regions of any given size.

Alexander, R. H.↗
NASA NTRS1970

Geography program, design, structure and operational strategy

The geography program is designed to move systematically toward a capability to increase remote sensing data into operational systems for monitoring land use and related environmental change. The problems of environmental imbalance arising from rapid urbanization and other dramatic changes in land use are considered. These overall problems translate into working level problems of establishing the validity of various sensor-data combinations that will best obtain the regional land use and environmental information. The goal, to better understand, predict, and assist policy makers to regulate urban and regional land use changes resulting from population growth and technological advancement, is put forth.

Alexander, R. H.↗
NASA NTRS1969

Geographic applications program: Reports completed and in preparation

The purpose of the present compilation is to bring together for ready reference a list of all reports, both completed and in preparation, resulting from NASA sponsorship of the geography program. Wherever possible, complete bibliographic citations are given. Since some of the 141 reports listed are not yet completed, citations can not all be in complete form. The reason for including incomplete citations is the sponsor's need for rather rapid feed-back of information so that it can have a bearing on on-going program planning. This should, therefore, be considered a working bibliography.

Alexander, R. H.↗
NASA NTRS1968

Remote sensing of urban environments.

Remote sensing of urban environments for metropolitan information systems noting photographic, thermal IR, radar and microwave applications

Alexander, R. H.↗