ISSN:0143-1161    

DOI:10.1080/01431169308904294

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Abstract. A technique for integrating spatial data of dissimilar type, scale, resolution and information content was developed. The technique, statistical overlay, calibrates statistics from one lower resolution data source against those from another sampled higher resolution source, A multi-variate inequality constrained least squares approach is used. The method was tested for use in estimation of deforestation in the tropics. Interpretation maps of Landsat Thematic Mapper imagery from the Instituto Brasileiro do Meio Ambiente e dos Rccursos Naturais Renovaveis (IBAMA) as well as an Advanced Very High Resolution Radiometer (AVHRR) mosaic of the Amazon prepared by the U.N. Global Resource Information Database (UNEP/GRID) Geneva, were used for data sources.

ISSN:0143-1161    

DOI:10.1080/01431169308904295

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

A new classification technique was proposed from the viewpoint of memory saving, as well as intensive processing time reduction, to meet the strong requirement for easier operation on a personal computer. To carry out this process efficiently, some neighbouring pixels were lumped into a cell. This idea is based on the fact that changes of the CCT counts in the sea area are monotone, that is histograms are symmetrical, and that cell by cell classification is, therefore, sufficient.

ISSN:0143-1161    

DOI:10.1080/01431169308904296

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Abstract. A new methodology for the linear feature enhancing of an image by filtering in Fourier space is presented. As a first step, the Fourier spectrum of the image is used to construct its rose diagram. A new filter is then applied in enhancement directions which are chosen directly from the rose diagram. In Fourier space, the proposed filter's transfer function is a surface whose section perpendicular to the enhanced direction is a Gaussian curve. The construction of this surface is made in such a way that filtering inanydirection is allowed. A sequence of analysis for the construction of an enhanced image using this filter is proposed. As an optional step, after constructing the enhanced image a binariza-tion can be made to facilitate the linear feature map extraction. The proposed binarization corresponds to the application of a local threshold technique. A pseudocode summary of each of the steps is included. A comparison with a simple directional filter is made.

ISSN:0143-1161    

DOI:10.1080/01431169308904297

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Abstract. By combining the brightness temperatures by NOAA-9/AVHRR and the sea surface temperature by Mutsu Bay automatic marine monitoring buoy system, the total number of 390 match-ups was set up. The temporal and spatial coincidence in each match-up is within 30 minutes and one pixel resolution. Following to the split-window method, a regression function for the sea surface temperature estimation was calculated and its standard deviation of estimation errors was 0-59°C. The residues were carefully examined with respect to the sensor calibration data and the meteorological data at match-up collections. Then it was found that large errors appeared when differences between the air temperature and the buoy temperature were large. Those were estimated to be caused by the air-sea interacting effects. By removing the match-ups with larger errors, a selected data set with 334 match-ups was prepared and the SST estimation function was recalculated. The standard deviation of errors reduced to 0-34 °C.

ISSN:0143-1161    

DOI:10.1080/01431169308904298

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Remotely-sensed data are presented from a sequence of overflights of the marine effluent discharge zone of a coastal power station complex. Emphasis is placed on studying the buoyancy-driven spreading of the thermally-enriched cooling water discharge from the power station outfall, under slack tide conditions. The results of the study show that the effects of local topography upon the spreading mode can be dominant under these conditions, and that the presence of solid barriers to the spreading flow can lead to complex deformations of the temperature field. It is demonstrated that simple reflection of the buoyancy-driven surface flow by islands results in the generation of localised regions possessing both high velocity shear and convergence. Surface foam lines are then formed within these regions. Data are presented to show the coincidence of the foam line positions with the edges of the surface plume, and this coincidence is discussed in the context of the flow patterns inferred from the thermographic data.

ISSN:0143-1161    

DOI:10.1080/01431169308904299

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

A remote sensing technique has been developed for quickly detecting suspended sediment concentration and monitoring the transport and deposition of suspended sediment in a large estuary area4. There is an agreement that the best wave band to analyse suspended sediment concentration is 0-6-0-8μm (MSS 5 and TM 3 for Landsat), but it is suggested that there is a divergence between which model is used to study the suspended sediment best. This paper presents a unified model for a quantitative approach to suspended sediment concentration using remote sensing. The comparison between various models with field investigation data and published data has shown that the unified model has a higher correlation and precision than most popular models used currently. The author illustrates that the logarithm model is flawed when suspended sediment concentration is high. The unified model has been applied to the quantitative remote sensing of suspended sediment in Lingdingyang, the Pearl River estuary (the biggest river in South China). Further improvement to the unified model with TM3/TM5 ratio technique has also been proposed to minimize the background influences (atmospheric and solar effects). Results show that the improved unified model has more advantages than other models which usually need a large number of field data each time they are used. The improved united model can be applied to a global scale after its parameters are classified according to different regions.

ISSN:0143-1161    

DOI:10.1080/01431169308904300

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Three different incidence angle data sets, obtained by the Shuttle Imaging Radar-B in October 1984 over a forested area in northern Florida, were combined with Landsat-5 Thematic Mapper data, to create a digitally registered 10 channel optical/microwave data set. The work discussed in this paper involved the analysis of the data obtained by the two sensors separately and in combination, to determine if there are synergistic effects obtained through the simultaneous use of data obtained from both the optical and microwave portion of the spectrum. The radar data were filtered with a low-pass filter to eliminate the speckle noise. Classifications of the TM, SIR-B and combined TM +SIR-B data sets were performed with both per-point and contextual classifiers. The results showed that filtered radar data can be used to classify accurately major cover types (i.e., pine forest, swamplands and radar smooth targets) and that the contextual classifier provided better classification performance. The combined TM and SIR-B data provided statistically improved classification performances compared to classifications from the three incidence angle SIR-B data, or the TM data alone. A four band subset (TM-2, TM-4, TM-5, and SIR-B 28°) of the 10 channels of the combined TM and SIR-B data set provided higher classification performances (91 per cent overall performance) than the 10 channel data set (86 per cent overall performance).

ISSN:0143-1161    

DOI:10.1080/01431169308904301

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Abstract. Satellite data are routinely used to monitor the growing season over the Sahelian zone of Africa. This study seeks to relate the vegetation indices and the rainfall estimates, both derived from meteorological satellites, to help monitor and predict the production of rangelands and marginal agricultural areas. Plant water use was calculated from a simple model which lakes into account the timing and distribution of rainfall: over a three-year period, the response of the Normalised Difference Vegetation Index (NDVI) to this quantity was consistent and was spatially quantified for two calibration years. A predictive model for end-of-season accumulated NDVI was developed and validated for a test year.

ISSN:0143-1161    

DOI:10.1080/01431169308904302

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Abstract. The anthesis-to-maturity period is a deciding phase in end wheat-yield because it corresponds to formation and filling of the grains. An experimental approach showed that it was possible to estimate an agronomical variable (EWC=ear water concentration( related to phenological development from multidate radiometric data in the SPOT bands.

ISSN:0143-1161    

DOI:10.1080/01431169308904303

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor