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951.
Neuralizing target superresolution algorithms 总被引:1,自引:0,他引:1
Tatem et al. (2001) have designed a Hopfield network-based algorithm for superresolving discrete targets that are larger than the sample spacing of an image. The algorithm iteratively minimizes a criterion function that contains a sigmoidal activation term. We have altered their algorithm to bring it in line with Hopfield's original network by reducing the pseudotemperature of the sigmoid. We found that smaller values of the pseudotemperature lead to faster convergence to a solution and resulting solutions that are more accurate. 相似文献
952.
953.
The most important advantage of the low resolution National Oceanic and Atmospheric Administration’s Advanced Very High Resolution
Radiometer (NOAA AVHRR) data is its high temporal frequency and high radiometric sensitivity which helps in vegetation detection
in the visible and near-infrared spectral regions. In areas where most of the crop cultivation is in large contiguous areas,
and if the AVHRR data are selected for time period such that the crop of interest is well discriminated from other crops,
these data can be used for monitoring vegetative growth and condition very effectively. The present study deals with the application
of AVHRR data for the monitoring of the wheat crop in its seventeen main growing districts of the Rajasthan state. The fourteen
date AVHRR data covering the entire growth period have been used to generate the normalized difference vegetation index (NDV1)
growth profile for the crop by masking the non-crop pixels following the two-date NDVI change method. The growth profile parameters
and other derived parameters, such as post-anthesis senescence rate and areas under the entire growth profile or under selected
growth periods have been related to the district average wheat yield through statistical regression models. Various methods
adopted for wheat pixels masking have been critically evaluated. It is found that the wheat yield can be predicted well by
the area under the profile in different growth periods. 相似文献
954.
Indrani?ChoudhuryEmail author M.?Chakraborty 《Journal of the Indian Society of Remote Sensing》2004,32(4):373-385
This study investigates the potential of multi-temporal signature analysis of satellite imagery to map rice area in South
24 Paraganas district of West Bengal. Two optical data (IRS ID LISS III) and three RADARSAT SAR data of different dates were
acquired during 2001. Multi-temporal SAR backscatter signatures of different landcovers were incorporated into knowledge based
decision rules and kharif landcover map was generated. Based on the spectral variation in signature, the optical data acquired
during rabi (January) and summer (March) season were classified using supervised maximum likelihood classifier. A co-incidence
matrix was generated using logical approach for a combined “rabi-summer” and “kharif-rabi-summer” landcover mapping. The major
landcovers obtained in South 24 Paraganas using remote sensing data are rice, water, aquaculture ponds, homestead, mangrove,
and urban area. The classification accuracy of rice area was 98.2% using SAR data. However, while generating combined “kharif-rabi-summer”
landcovers, the classification accuracy of rice area was improved from 81.6% (optical data) to 96.6% (combined SAR-Optical).
The primary aim of the study is to achieve better accuracy in classifying rice area using the synergy between the two kinds
of remotely sensed data. 相似文献
955.
R. Ramakrishnan S. Manthira Moorthi N. Padmanabhan P. Gupta 《Journal of the Indian Society of Remote Sensing》2004,32(1):103-111
Panchromatic data of pixel resolution 5.8 m obtained from IRS-1C and IRS-1D satellites proved to be very useful for mapping
purposes. One of the popular data product is the 70 km swath mosaic which is covered by a combination of 3 CCD line sensors,
each with 4096 pixels. Each CCD-line sensor with different imaging times causes geometric problems of mosaicing three strips
data together. In this paper, we propose the details of the design elements of system that caters to the need for accurate
and automatic multi strip image registration without any second resampling of the data. The systematic geometric correction
grid mapping is improved to facilitate accurate mosaicing by automatic image registration task that makes use of the overlap
data within image strips and image registration is achieved up to sub-pixel level. 相似文献
956.
957.
T.W. Foresman T. Cary T. Shupin R. Eastman J.E. Estes N. Faust J.R. Jensen K.K. Kemp 《ISPRS Journal of Photogrammetry and Remote Sensing》1997,52(6):294-300
The Remote Sensing Core Curriculum (RSCC) was initiated in 1993 to meet the demands for a college-level set of resources to enhance the quality of education across national and international campuses. The American Society of Photogrammetry and Remote Sensing adopted the RSCC in 1996 to sustain support of this educational initiative for its membership and collegiate community. A series of volumes, containing lectures, exercises, and data, is being created by expert contributors to address the different technical fields of remote sensing. The RSCC program is designed to operate on the Internet taking full advantage of the World Wide Web (WWW) technology for distance learning. The issues of curriculum development related to the educational setting, with demands on faculty, students, and facilities, is considered to understand the new paradigms for WW-influenced computer-aided learning. The WWW is shown to be especially appropriate for facilitating remote sensing education with requirements for addressing image data sets and multimedia learning tools. The RSCC is located at http://www.umbc.edu/rscc 相似文献
958.
Remote sensing of horticultural plantations in Kumarsain tehsil in Shimla district, Himachal Pradesh
M M Kimothi M H Kalubarme Sujay Dutta Rajendra Thapa R K Sood 《Journal of the Indian Society of Remote Sensing》1997,25(1):19-26
The favourable agroclimatic conditions for orchards especially apples have increased the acreages in Himachal Pradesh (HP) which has significantly contributed in the growth of state economy. Realizing the importance of horticulture in HP and its changing scenario of the land use/land cover, a study was conducted to identify and map apple and almond plantations in the Kumarsain tehsil of Shimla district using Remote Sensing (RS) techniques. IRS-IB LISS-II False Colour Composite (FCC) diapositives of October 27, March 30 and April 20, 1992 were visually analysed for mapping apple and almond plantations. The results indicate that IRS LISS-II data of April 20 on 1∶50,000 scale was found very useful for identification and mapping of apple and almond plantations in this region. Accuracy of interpretation was also tested on sample basis assuming a binomial distribution for the probability of success/failure of sample points. The overall interpretation accuracy assessed based on 40 sample points was found to be 87 per cent at 90 per cent confidence limits. 相似文献
959.
M M Jana 《Journal of the Indian Society of Remote Sensing》1997,25(2):105-111
River basin management and development are most important for utilising and conserving the water resources in any region where the average annual rainfall is highly fluctuating, the North Bengal is one of such region. Though there are a large number of rivers having a large catchment area in the hills and carry a huge amount of water during rainy season but they are completely dry in winter and summer. The upper part of majority of river basins arc highly sensitive to water erosion and land slides due to deforestation, intensive cultivation, increased settlements in sloping and erosion prone areas. So, floods in the rainy season and droughts in summer months are frequent features in North Bengal. In view of this proper management and effective conservation of land and water resources is necessary to develop the region. An integrated river basin management consisting soil conservation, afforestation, flood control, and adoption of suitable cropping pattern is essential for economic development of North Bengal. 相似文献
960.
M. Premalatha P. P. Nageswara Rao 《Journal of the Indian Society of Remote Sensing》1994,22(3):139-147
Synthetic Aperture Radar (SAR) data from the European Remote Sensing Satellite (ERS-1) acquired in July, October and November, 1992 covering the kharif season of the region were used separately and in combination to identify the major crops and for estimation of their acreage before harvest Separability indices were calculated for major cover types and it was found that single-date SAR data cannot be used for accurate identification of various crops. Multi-temporal colour composite facilitated better identification of crop types. Comparison of area estimates made with ERS-1 SAR and IRS-1B LISS II data showed that the commonly used digital data analysis techniques (per pixel classifiers) are not adequate for accurate estimation of crop acreage using SAR data. 相似文献