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Hay, C. M.

Publications and source records attributed to Hay, C. M..

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1983

Application of a U.S.-based analysis approach to Argentina crop identification

A generic, U.S.-based analysis approach was evaluated with respect to corn and soybean identification in Argentina. Using crop separability expectations derived from the analysis of Argentina ancillary data and U.S. spectral data, the approach was applied to Argentina spectral data by an expert analyst. Eight classes were detected and labeled independent of ground data. A high correspondence between the labels and limited ground data was achieved. It was concluded that an approach of this type could be applied to Argentina without major difficulty.

Odenweller, J. B.↗
NASA NTRS1982

Labeling research in support of through-the-season area estimation

The development of LANDSAT-based through-the-season labeling procedures for corn and soybeans is discussed. A model for predicting labeling accuracy within key time periods throughout the growing season is outlined. Two methods for establishing the starting point of one key time period, viz., early season, are described. In addition, spectral-temporal characteristics for separating crops in the early season time period are discussed.

Colwell, R. N.↗
NASA NTRS1979

Manual interpretation of LANDSAT data

The task of the analyst throughout LACIE phases 1 and 2 consisted of outlining representative areas (fields) for all spectral classes within a segment on the basis of their appearance on the LANDSAT image products, and then labeling the crop type (wheat/nonwheat) within the selected training areas. For LACIE phase 3, a procedure was developed and implemented which incorporated clustering for spectral class definition and training statistics generation. The only analyst's task was crop type identification. The logical processes involved in interpretation are described, rather than a step-by-step description of analyst procedures.

Hay, C. M.↗
NASA NTRS1979

Development of partitioning as an aid to spectral signature extension

Lists of spectrally similar LACIE sample segments may be constructed with the use of three basic information types: static, seasonal, and pass-specific variables. All are related directly or indirectly to spectral signature behavior and can be used to define spatial domains over which crop-specific signatures should be extendable. Topics covered include: (1) static spectral stratification; (2) evaluation of static partitions relative to variance control objectives; (3) evaluation of the relative importance of static versus seasonal and pass-specific partitioning variables in spectral variability; and (4) a current perspective on partitioning.

Thomas, R. W.↗
NASA NTRS1979

Manual LANDSAT data analysis for crop type identification

The process of manual identification of crop type by human analysts and problems associated in LACIE that were associated with manual crop identification measurement procedures are described. Research undertaken in cooperation with LACIE operations by the supporting research community to effect solutions to, or obtain greater understanding of the problems is discussed.

Hay, C. M.↗
NASA NTRS1977

Development of techniques for producing static strata maps and development of photointerpretive methods based on multitemporal LANDSAT data

Progress in the evaluation of the static stratification procedure and the development of alternative photointerpretive techniques to the present LACIE procedure for the identification of training fields is reported. Statistically significant signature controlling variables were defined for use in refining the stratification procedure. A subset of the 1973-74 Kansas LACIE segments for wheat was analyzed.

Colwell, R. N.↗
NASA NTRS1977

Two phase sampling for wheat acreage estimation

A two phase LANDSAT-based sample allocation and wheat proportion estimation method was developed. This technique employs manual, LANDSAT full frame-based wheat or cultivated land proportion estimates from a large number of segments comprising a first sample phase to optimally allocate a smaller phase two sample of computer or manually processed segments. Application to the Kansas Southwest CRD for 1974 produced a wheat acreage estimate for that CRD within 2.42 percent of the USDA SRS-based estimate using a lower CRD inventory budget than for a simulated reference LACIE system. Factor of 2 or greater cost or precision improvements relative to the reference system were obtained.

Thomas, R. W.↗
NASA NTRS1977

Two phase sampling for wheat acreage estimation

A two-phase Landsat-based sample allocation and wheat proportion estimation method was developed. The technique employs manual, Landsat full frame-based wheat or cultivated land proportion estimates from a large number of segments comprising a first sample phase to optimally allocate a small phase-two sample of computer or manually processed segments. Proportion estimates from each phase are then linked by regression or probability proportional to estimated size estimators to provide wheat proportion estimates and standard errors by reporting unit. Application to the Kansas Southwest CRD (Crop Reporting District) for 1974 produced a wheat acreage estimate for that CRD within 2.42% of the USDA SRS-based estimate using a lower CRD inventory budget than for a simulated reference LACIE (Large Area Crop Inventory Experiment) system.

Thomas, R. W.↗
NASA NTRS1977

Two phase sampling for wheat acreage estimation

A two phase Landsat-based sample allocation and wheat proportion estimation method was developed. This technique employs manual, Landsat full frame-based wheat or cultivated land proportion estimates from a large number of segments comprising a first sample phase to optimally allocate a smaller phase two sample of computer or manually processed segments. Application to the Kansas Southwest CRD for 1974 produced a wheat acreage estimate for that CRD within 2.42 percent of the USDA SRS-based estimate using a lower CRD inventory budget than for a simulated reference LACIE system. Factor of 2 or greater cost or precision improvements relative to the reference system were obtained

Thomas, R. W.↗
NASA NTRS1976

Development of techniques for producing static strata maps and development of photointerpretation methods based on multitemporal LANDSAT data

The progress of research conducted in support of the Large Area Crop Inventory Experiment (LACIE) is documented. Specific tasks include (1) evaluation of the static stratification procedure and modification of that procedure if warranted, and (2) the development of alternative photointerpretative techniques to the present LACIE procedures for the identification and selection of training fields (areas).

Colwell, R. N.↗
NASA NTRS1976

A remote sensing-aided small grains inventory using sequential Landsat imagery

A procedure for manual acreage estimation from Landsat imagery is proposed which involves a stepwise sequence of area stratification, simple size estimation, acreage estimation, and acreage precision calculation. The sample design consists of a systematic point sample of the Landsat imagery for crop type presence calibrated by a double sample of several image points having crop season-coincident ground data. The sample point layout chosen for cost-efficiency in manual sampling is a doubly aligned point matrix. The significant advantage of this sampling approach is that crop information is available from throughout the agricultural reporting unit. For technique demonstration purposes three strata were selected for sampling. The proposed technique can complement more sophisticated computer-based acreage estimation methodologies, and refinements in the sampling techniques promise significant improvements for operational utility.

Thomas, R. W.↗
NASA NTRS1974

Agricultural inventory techniques with orbital and high-altitude imagery

An investigation was conducted regarding the feasibility of an employment of satellite imagery for land-use stratifications, taking into account present operational systems. It was found that satellite imagery of the quality of ERTS-1 can offer a feasible solution to the problem of out-of-date stratification. Other studies reported are concerned with the level of accuracy obtainable in a crop inventory for a specific crop using high-altitude aircraft photographs.

Hay, C. M.↗
NASA NTRS1974

Regional agriculture surveys using ERTS-1 data

The Center for Remote Sensing Research has conducted studies designed to evaluate the potential application of ERTS data in performing agricultural inventories, and to develop efficient methods of data handling and analysis useful in the operational context for performing large area surveys. This work has resulted in the development of an integrated system utilizing both human and computer analysis of ground, aerial, and space imagery, which has been shown to be very efficient for regional crop acreage inventories. The technique involves: (1) the delineation of ERTS images into relatively homogeneous strata by human interpreters, (2) the point-by-point classification of the area within each strata on the basis of crop type using a human/machine interactive digital image processing system; and (3) a multistage sampling procedure for the collection of supporting aerial and ground data used in the adjustment and verification of the classification results.

Draeger, W. C.↗
NASA NTRS1973

Applications of remote sensing to agriculture

Remote sensing applications to agriculture in the areas of: (1) general land use mapping and stratification, (2) identification, and inventory of distinct crops, and (3) detection of stress conditions and other factors affecting crop yields are discussed.

Hay, C. M.↗
NASA NTRS1971

Multiband photography - Forestry and agricultural applications.

The usefulness of multiband photography in forestry and agricultural applications was evaluated by a large group of skilled photo interpreters within four California test sites. Environmental parameters selected included crop types, forest vegetation types, and tree species composition. Quantitative analyses were made of the interpretability of (1) multiband black and white photos viewed separately, (2) multiband black and white photos combined into true and false color composites, and (3) color and color infrared photos obtained simultaneously with the multiband black and white photography. Tests indicated that multiband photography consistently yielded higher interpretation accuracies than any types of single-band photography. Black and white multiband photos which were properly procured and displayed as false-color composite imagery in all cases rendered as much (or as little) information as conventional tri-emulsion color or infrared color film.

Lauer, D. T.↗