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Estes, J. E.

Publications and source records attributed to Estes, J. E..

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1993

Spatial structure, sampling design and scale in remotely-sensed imagery of a California savanna woodland

This article describes research related to sampling techniques for establishing linear relations between land surface parameters and remotely-sensed data. Predictive relations are estimated between percentage tree cover in a savanna environment and a normalized difference vegetation index (NDVI) derived from the Thematic Mapper sensor. Spatial autocorrelation in original measurements and regression residuals is examined using semi-variogram analysis at several spatial resolutions. Sampling schemes are then tested to examine the effects of autocorrelation on predictive linear models in cases of small sample sizes. Regression models between image and ground data are affected by the spatial resolution of analysis. Reducing the influence of spatial autocorrelation by enforcing minimum distances between samples may also improve empirical models which relate ground parameters to satellite data.

Mcgwire, K.↗
NASA NTRS1993

A remote sensing research agenda for mapping and monitoring biodiversity

A remote sensing research agenda designed to expand the knowledge of the spatial distribution of species richness and its ecological determinants and to predict its response to global change is proposed. Emphasis is placed on current methods of mapping species richness of both plants and animals, hypotheses concerning the biophysical factors believed to determine patterns of species richness, and anthropogenic processes causing the accelerating rate of extinctions. It is concluded that biodiversity should be incorporated more prominently into the global change and earth system science paradigms.

Stoms, D. M.↗
NASA NTRS1986

Performance analysis of image processing algorithms for classification of natural vegetation in the mountains of southern California

The earth's forests fix carbon from the atmosphere during photosynthesis. Scientists are concerned that massive forest removals may promote an increase in atmospheric carbon dioxide, with possible global warming and related environmental effects. Space-based remote sensing may enable the production of accurate world forest maps needed to examine this concern objectively. To test the limits of remote sensing for large-area forest mapping, we use Landsat data acquired over a site in the forested mountains of southern California to examine the relative capacities of a variety of popular image processing algorithms to discriminate different forest types. Results indicate that certain algorithms are best suited to forest classification. Differences in performance between the algorithms tested appear related to variations in their sensitivities to spectral variations caused by background reflectance, differential illumination, and spatial pattern by species. Results emphasize the complexity between the land-cover regime, remotely sensed data and the algorithms used to process these data.

Yool, S. R.↗
NASA NTRS1986

Remote Sensing Information Sciences Research Group, Santa Barbara Information Sciences Research Group, year 3

Research continues to focus on improving the type, quantity, and quality of information which can be derived from remotely sensed data. The focus is on remote sensing and application for the Earth Observing System (Eos) and Space Station, including associated polar and co-orbiting platforms. The remote sensing research activities are being expanded, integrated, and extended into the areas of global science, georeferenced information systems, machine assissted information extraction from image data, and artificial intelligence. The accomplishments in these areas are examined.

Estes, J. E.↗
NASA NTRS1986

Support for global science: Remote sensing's challenge

Remote sensing uses a wide variety of techniques and methods. Resulting data are analyzed by man and machine, using both analog and digital technology. The newest and most important initiatives in the U. S. civilian space program currently revolve around the space station complex, which includes the core station as well as co-orbiting and polar satellite platforms. This proposed suite of platforms and support systems offers a unique potential for facilitating long term, multidisciplinary scientific investigations on a truly global scale. Unlike previous generations of satellites, designed for relatively limited constituencies, the space station offers the potential to provide an integrated source of information which recognizes the scientific interest in investigating the dynamic coupling between the oceans, land surface, and atmosphere. Earth scientist already face problems that are truly global in extent. Problems such as the global carbon balance, regional deforestation, and desertification require new approaches, which combine multidisciplinary, multinational research teams, employing advanced technologies to produce a type, quantity, and quality of data not previously available. The challenge before the international scientific community is to continue to develop both the infrastructure and expertise to, on the one hand, develop the science and technology of remote sensing, while on the other hand, develop an integrated understanding of global life support systems, and work toward a quantiative science of the biosphere.

Estes, J. E.↗
NASA NTRS1986

Pilot land data system

The Pilot Land Data System (PLDS) is a multi-institutional effort directed towards solving the data access and management needs of scientists studying the land surface. Some of the hardware and software, which are now available, are reviewed.

Star, J. L.↗
NASA NTRS1986

Neotectonics of the San Andreas fault system: Basin and range province juncture

Several new details regarding the surficial patterns of neotectonic activity of the Eastern Transverse Ranges and vicinity were discovered. Additionally a number of data display and analysis techniques were developed. These findings will be useful both in the continued development of neotectonic models for southern California and for the future application of remote sensing methodologies elsewhere.

Estes, J. E.↗
NASA NTRS1986

COVER Project and Earth resources research transition

Results of research in the remote sensing of natural boreal forest vegetation (the COVER project) are summarized. The study objectives were to establish a baseline forest test site; develop transforms of LANDSAT MSS and TM data for forest composition, biomass, leaf area index, and net primary productivity; and perform tasks required for testing hypotheses regarding observed spectral responses to changes in leaf area index in aspen. In addition, the transfer and documentation of data collected in the COVER project (removed from the Johnson Space Center following the discontinuation of Earth resources research at that facility) is described.

Botkin, D. B.↗
NASA NTRS1986

Support for global science - Remote sensing's challenge

Advances in remote sensing techniques are discussed. The benefits possible to remote sensing with the new Earth Observing System, which is composed of the Space Station and coorbiting and polar satellite platforms, are examined. Current changes in the remote sensing field, which involve a change from an industrial society to an informational society, force technology to high technology with high touch, short term to long term, centralized to decentralized, hierarchies to networks, and either/or to multiple option systems are studied. The explanatory and objective types of analyses for investigating biophysical, geochemical, and socioeconomic processes are described; the procedures include: morphometric, cause and effect, temporal and functional and ecological system analyses, inventory, mapping, monitoring, and modeling.

Estes, J. E.↗
NASA NTRS1985

Pilot land data system

The full realization of the potential of satellite remote sensing would require the utilization of information systems which are currently not available. However, technological advances make it now possible to design a data system for meeting the land scientists' most critical information needs. A working group has been assembled to examine the need for a Pilot Data System (PLDS). The pilot program is to establish a limited-scale, distributed information system to explore approaches to satisfy the needs of the land science research community. Aspects and objectives considered by the working group are discussed, taking into account science scenarios, required functions, the characteristics of a land data system, and questions of pilot land data system development.

Estes, J. E.↗
NASA NTRS1984

NASA Pilot Land Data System

Project development and planning for a Pilot Land Data System (PLDS) are discussed. The PLDS supplies basic information, data management, and data processing capabilities to the land research community. Topics on design and implementation, user requirements, and project management are examined. The scenarios developed thusfar are also included.

Estes, J. E.↗
NASA NTRS1984

Knowledge-based Expert Systems for Crop Identification

The development of an improved understanding of the interactive man machine environment is investigated. In such an environment, as many feature inputs as practical would be automatically derived from a data base and input into an expert system decision making procedure. This procedure could then provide expert assistance to a trained image analyst to upgrade and improve the quantity and accuracy of the information extracted from the input data. A comparison of the similarities and differences between manual and automated image interpretation techniques is also examined.

Smith, T. R.↗
NASA NTRS1984

Annotated Bibliography of Global Resources Information Systems Related Publications

An annotated bibliography of work concerning geophysical data management systems is presented. Major topics under investigation include data acquisition, data storage, long term data preservation, architecture, preprocessing, hydrology, land resources, geology, meteorology, and applications of remote sensing techniques.

Estes, J. E.↗
NASA NTRS1984

Global Resources Information System

The basic design criteria and operating characteristics of a Global Resources Information System GRIS are defined. Researchers are compiling background material and aiding JPL personnel in this project definition phase of GRIS. A bibliography of past studies and current work on large scale information systems is compiled. The material in this bibliography will be continuously updated throughout the lifetime of this grant. Project management, systems architecture, and user applications are also discussed.

Estes, J. E.↗
NASA NTRS1984

Pilot land data system

During the fall of 1983, the Information Systems Office of NASA's Office of Space Science and Applications assembled a Working Group to develop initial plans for a Pilot Land Data System (PLDS). Workshops coordinated planning and concept development activities between land-related and computer science disciplines, and examined land research requirements, information science technology requirements, PLDS architecture, and methodologies for system evaluation. The PLDS will be a limited-scale distributed information system to explore scientific, technical and management approaches to satisfy land science research needs. PLDS will pave the way for a Land Data System to improve data access, processing, transfer and analysis, fostering an environment in which land science information synthesis can occur on a scale not previously possible owing to limits to data assembly and access and efficiency of processing.

Cressy, P. J.↗
NASA NTRS1982

Multispectral determination of soil moisture-2

Soil moisture data obtained using scatterometers, modular multispectral scanners and passive microwave radiometers were revised and grouped into four field cover types for statistical anaysis. Guymon data are grouped as alfalfa, bare, milo with rows perpendicular to the field view, and milo viewed parallel to the field of view. Dalhart data are grouped as bare combo, stubble, disked stubble, and corn field. Summary graphs combine selected analyses to compare the effects of field cover. The analysis for each of the cover types is presented in tables and graphs. Other tables show elementary statistics, correlation matrices, and single variable regressions. Selected eigenvectors and factor analyses are included and the highest correlating sensor typs for each location are summarized.

Estes, J. E.↗
NASA NTRS1982

Neotectonics of the San Andreas Fault system, basin and range province juncture

The development, active processes, and tectonic interplay of the southern San Andreas fault system and the basin and range province were studied. The study consist of data acquisition and evaluation, technique development, and image interpretation and mapping. Potentially significant geologic findings are discussed.

Estes, J. E.↗