ISSN:0143-1161    

DOI:10.1080/01431168508948326

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

ISSN:0143-1161    

DOI:10.1080/01431168508948327

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

This paper presents a forest inventory study of the Mao-shan area, a region which is partly representative of the forest types of southern China. In the study, the effectiveness of various feature extraction techniques was investigated, new classification algorithms were developed and supervised classification schemes were implemented and assessed. A scheme involving two-dimensional spectrum decomposition classification, manual editing and Bayes classification is proposed. Its application gives results which show promising potential for forest inventory in southern China using computer processing of LANDSAT imagery.

ISSN:0143-1161    

DOI:10.1080/01431168508948328

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

This study evaluated the potential of an autumn LANDSAT MSS diazo-enhanced composite which consisted of one yellow copy of band4, three magenta copies of band 5 and one cyan copy of band 7, to map an area of small scattered forestlands. The standard colour composite of the same scene was also used for comparative purposes. The best diazo composite was made by high-contrast films. The diazo technique used is discussed briefly. Interpretation errors were characterized as commission errors and omission errors which were further classified by size and into errors of boundary placement and errors of identification. Furthermore, they were classified according to land-cover/use and stocking-level stand-size classification systems. The three types of accuracy calculated (classification, interpretation and mapping) indicated, first, the potential of mapping forestlands on a LANDSAT image and, second, that the diazo composite improved the interpretation performance over the standard composite. On both images most of the interpretation errors were classified as boundary errors. The most frequently misclassified areas were agriculture, treed bog and brushland and also lowland hardwoods, mixed hardwoods and oak-hickory stands. The stocking level of the stands affected the interpretation more than the stand size, Over 50 per cent of the interpretation errors on both images were less than 2-0 ha in size. However, the distribution of errors skewed more towards smaller size classes in the case of the diazo composite.

ISSN:0143-1161    

DOI:10.1080/01431168508948329

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

Canopy spectral reflectances were measured over six cultivars of spring wheat (Trticum aestivumL.) grown at Phoenix, Arizona. Data were collected at 30-45 min intervals on 9 March 1983 using two ground-based radiometers with bandpass characteristics similar to those of the Muttispectral Scanner and Thematic Mapper on LANDSAT-4 and -5. Major differences in reflectance were observed among cultivars at every time period despite their apparent similarities in green leaf area and green biomass. Single-leaf spectra measured in the laboratory with a spectrophotometer revealed no cultivar-related differences and supported the contention that the reflectances were strongly influenced by canopy architectural features. The diurnal patterns of reflectance reinforced this conclusion with planophile canopies exhibiting the least amount of variability due to changes in Sun angle and erectophile canopies showing the most. These data underscore the complexities of interpreting remotely sensed multispectral data and suggest that multiple Sun-angle data acquisitions may be required to extract desired information.

ISSN:0143-1161    

DOI:10.1080/01431168508948330

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

Comparisons of the spectral response for incomplete (well-defined row structure) and complete (overlapping row structure) canopies indicated that there was a greater dependence on Sun and view geometry for the incomplete canopies. This effect was more pronounced for the highly absorptive red (0.6-0.7 μm) wavelength band than for the near-infrared (IR) (0.8-1.1 μm) based on relative reflectance factor changes.

ISSN:0143-1161    

DOI:10.1080/01431168508948331

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

ISSN:0143-1161    

DOI:10.1080/01431168508948333

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

ISSN:0143-1161    

DOI:10.1080/01431168508948334

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

Optical flow methods are a recent technological merger of numerical modelling and remote sensing/image processing techniques, used to derive an estimate of an Eulerian flow field for some hydrodynamic surface. Flow determinations are based on spatial and temporal tracer gradients, derived from time sequential remotely sensed data. A well-posed mathematical model has been formulated, and it is shown that an alternative numerical solution method to conventional finite difference schemes must be utilized (e.g. method of characteristics) to generate meaningful solutions. State-of-the-art (but not necessarily operational) remote sensing/image processing technology is capable of supplying tracer information suitable for reasonably accurate optical flow estimates for cloud-free time sequences.

ISSN:0143-1161    

DOI:10.1080/01431168508948336

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor