最新刊期
卷 ， 期 4 ， 2004
- 摘要：The confidence band model of uncertainty propagation on vector buffer in GIS is proposed in this paper. The buffer confidence band of point feature and liner feature is discussed respectively. A new coefficient, K , similar to relative accuracy is suggested to estimate confidence band quantitatively. The formula to compute the coefficient is introduced. The test section mainly discusses the effect of the factors, finally this paper concludes that the error of line vertex and confidence level is the key factor to the uncertainty propagation during the buffer operation.关键词：GIS;vector buffer;uncertainty propagation;confidence band
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发布时间：2021-06-10 - 摘要：Now the remote sensing of LST is an important task of us. Components temperature retrieval is the main object of LST retrieval. If the emissitivity or temperature of components is obviously different, the information of components’ temperature can be extracted from the multi angle radiance data. In this paper, we construct the matrix model of infrared radiance, analyze the correlation of W K×J , choose the optimal viewing angles and select the parameters that can be retrieved. Then based on data of the airborne sensor AMTIS developed in China, through geometrical and atmospherical correction, the plant and soil temperature in mixed pixels are separated using matrix retrieval method. The results and the error analysis show that the accuracy of retrieved soil temperature is good, but the result of retrieved plant temperature is not good enough.关键词：AMTIS;Thermal infrared remote sensing;multi angle;retrieval of component temperature
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发布时间：2021-06-10 - 摘要：The knowledge of foliar biochemical concentration provides us a deep understanding of many esosystem functions, such as photosynthesis, nutrient cycling, and so on. Generally speaking, two ways of biochemical concentration estimation by remote sensing, namely statistical regression and physical model inversion, have been studied in parallel. There are many limitations in statistical regression method. So, direct inversion of physical model is desired. From the view of inverting physical models to retrieve biochemical concentration, inversion methods were analyzed at leaf and canopy level respectively. At leaf level, using laboratory measured spectra and PROSPECT model, water and chlorophyll concentration were inverted quite accurately. Through comparing true spectra with reconstructed spectra using true inputs, results were got as that accurate inversion of some parametes are based on the model which should describe the effect of this parameter accurately. At simulated canopy level, preliminary inversion of biochemical content directly from canopy spectra showed poor accuracy especially for chlorophyll. Based on the idea of multi stage inversion, following inversion was decomposed into 2 parts: first from canopy spectra to leaf spectra, then from leaf spectra to biochemical content. By this step by step inversion strategy, biochemical concentration was inverted accurately ultimately.It should be noted that in this paper the canopy spectra was simulated by model, further testifying with real spectra is needed which we will take into consideation in near future. Also other inversion algorithms than iterative optimization will be tested.关键词：biochemical;inversion
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发布时间：2021-06-10 - 摘要：The precision of quantificational remote sensing can be enhanced by tapping the potential of sensor,transfer model and exact describing of the object. We think exactly of describing the object is the base of enhancing inversion precision of remote sensing. For this purpose,the vertical distribution of canopy nitrogen and Chl （a+b） status in winter wheat were studied. The spectral response of nitrogen and Chl（a+b） at different layer in canopy also had been analyzed. There appeared an apparent descending trend of nitrogen content from the upper layer to the lower layer. The nitrogen content of upper layer was higher than that of the middle layer with 13 3% and 29 5% between the middle layer and the lower layer in the growth duration. At early stage,the nitrogen content gradually increased with the increasing of the nitrogen application. But there were stable nitrogen gradient between different layers. There appeared greater nitrogen content gradient at middle and latter growth stage and the gradient sharpening with the nitrogen application amount. The vertical distribution property of Chl（a+b） concentration was similar to that of the nitrogen. But there were greater gradient of Chl（a+b） concentration than that of nitrogen content between upper and middle layer and less between middle and lower layer. The amount of nitrogen application decreased the Chl（a+b） gradient between middle and lower layer,which differ from that of nitrogen. Under the lower nitrogen condition,there existed significant reflectance difference among different layer at the red wavebands,the wavebands from 1400nm to 1800nm and from 1950nm to 2300nm.The reflectance of lower layer was significantly higher than that of upper and middle layer. But there was almost no difference among different layer with affluent nitrogen application. There was apparent gradient distribution in different layer and appeared gradually decreased from upper to lower layer at near infrared platform. But the amount of nitrogen application didn’t affect the gradient distribution characteristics of spectral reflectance. Besides,the correlative coefficients between canopy spectra and foliar biochemical contents of different layers were analyzed. The canopy spectral reflectance in different bands for remote sensing of foliar biochemical contents in different layers were found,and the spectral reflectance is significant correlative with foliar Chl（a+b） content of middle and lower layers. Future work should involve giving more attention on the method for multi angle analyzing and establishing inversion model.关键词：winter wheat;nitrogen content;vertical distribution;spectrum
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发布时间：2021-06-10 - 摘要：The purpose of this paper was mainly to interpret the pixel missing patch of image by using the kriging interpolation technology of spatial statistics. The TM image （a resolution of 30m×30m） of the Jingouling Forest Farm of the Wangqing Forestry Bureau of Northeast China on 1 July, 1997 was selected as data resource, and some patches with cloud and cloud shade from the TM image were adopted as experimental data in this paper. Based on the classification for the TM remote sensing image, the pixel information of real pixel missing patches of image （the real pixel missing patch is the patch with the unknown real information of partial regions on the image, which is caused by the shelters of cloud, cloud shade, soot and others） was restored by the kriging interpolation technology of spatial statistics theory under the image processing software—ERDAS, the geographic information system software—ArcInfo and the spatial statistics analysis software—ILWIS. The restored pixel information was reclassified, and then compared with the results of forest resource survey, thus the results （i.e. the classified precision of the restored information of each patch was more than 75%）, was obtained. Moreover, the kriging interpolation technology used in this paper grasped the fact that the objects on the global surface possessed continuity and self correlation, and therefore it had better estimation effects. Additionally, the applicable scopes and the applicable conditions of the kriging interpolation were discussed in detail from different aspects. In summary, this paper would provide a method and means for interpreting the pixel missing patch of image.关键词：spatial statistics;remote sensing;GIS;pixel missing patch;Kriging interpolation
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发布时间：2021-06-10 - 摘要：It is well known that natural language usually can provide much more precise and convenient spatial information in the context of social geographical information service. This paper researches the method of the GIS path reconstruction based on natural language （Chinese） containing geo spatial information, which is called as natural language representation of path （NLRP）. Through analyzing Chinese sentences that contain path representation, a syntax model of NLRP for Chinese is built, which mainly contains a set of actions with spatial constraint and action objects. As a rule, the action objects usually are geospatial features. Considering the contribution to the forming of a concrete path, the actions in NLRP can be classified into three types: durative actions, transitional actions and parallel actions. Durative actions can last for a period of time, and each of them forms one segment of the whole path; transitional actions change the state of the activities, such as “turn left”, and usually they start flags or end flags of a durative action; when a parallel action happens, the state doesn’t change, and it occurs inside another durative action both spatially and temporally, such as “pass by”. Generally speaking, durative actions are corresponding to linear features and time segments, while a non durative action, can be mapped to a specific event point in spatial and temporal space. In the model, the actions with spatial semantics can be defined precisely using 9 I matrix.According to the model above, the NLRP syntax for constrained Chinese language is defined using BNF. Then the path reconstruction algorithm （PRA） and two interrelated issues, i.e. dictionary design and software architecture design, are discussed. In PRA, using intermediate result of the syntax processing, which is a sequence of actions, the action series are analyzed and the spatial relationships between objective path and related features are examined based on the geographical reference map. At last, the concrete path can be figured out.Furthermore, a NLRP expression contains some uncertainties inevitably, which may come from the spatial cognition process and imprecise expression. The uncertainties of NLRP bring ambiguities to PRA, and increase the algorithm complexity. They include uncertainties of direction, uncertainties of distance and uncertainties of topologic relationship. Meanwhile, solution to them is also discussed, the essential of which is to distinguish major flag and minor flag of a durative action, and the former determines the shape of path, while the latter may be used to check errors of an NLRP description.Finally, a case study of PRA is described to validate it.关键词：NLRP;restricted Chinese language;path reconstruction;geospatial uncertainties
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发布时间：2021-06-10 - 摘要：There is a gap between traditional neural network’s information process ability and amount information of remote sensing image recognition. Focusing on this problem, this paper proposes a method to combine rough set theory with neural network theory and uses it in remote sensing image recognition. First, this paper analyzes the feasibility and advantages of combination of neural network with rough set theory. Based on this analysis, a rough set theory based remote sensing image recognition model is presented. Furthermore, analysis on rough set module and remote sensing image recognition module are given in details. Finally, contrastive experiment data are given to prove that combining rough set theory with neural network theory for remote sensing image recognition has a high converging rate, shorter training time and more accuracy.The potential of this method,is also shown.关键词：rough set theory;neural network;remote sensing image;image recognition
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发布时间：2021-06-10 - 摘要：To date, Remote Sensing technologies have been applied to environmental management, monitoring and control. Remote Sensing technologies are also being applied to monitor land desertification, land use cover, environment pollution, etc. Due to limitations in instrument and processing technology in RS, system errors and measurement errors may corrupt the data. Errors may be associated with both attribute value and its location. After collecting spatiald ata, we then need to process, analyze and convert the data in order to make RS information understandable to users. When we produce the final RS products, new errors can be created as a result of spatial operations on maps or images that contain errors （spatial error propagation）. If we ignore these errors in the RS products, it can result in economic loss. Though, the uncertainty of remote sensing information has been a hotspot in the spatial information process and many research have provided us lots of valuable results, however very few of them is on the mechanism based. The existing methods applied to the uncertainty analysis of RS will lead to the blind spot where uncertainty could not be analyzed,and uncertainty in subsequent image product will be propagated, tracked and quantified inconveniently. In this paper, we propose a framework to deal with these problems.关键词：remote sensing;uncertainty analysis;data analysis method;mechanism based method analysis
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发布时间：2021-06-10 - 摘要：The pathfinder AVHRR NDVI data are widely used for analyzing the response of vegetation condition to climate change. However, the Pathfinder NDVI data sets contain a lot of random errors due to various factors such as cloud, aerosols, instrumental interruption and changes and so on. To what extent these errors can influence the results of NDVI/climate connections? In the present work,the authors analyzed the impacts of NDVI errors on NDVI/temperature coupling in spring, by using singular value composition analysis technique. Four kinds of errors are tested, including the continuous, discontinuous and volcanic errors, and the error trends as well. Results show that when the errors are less than half the original NDVI standard deviation the SVD spatial modes and temporal changes are stable and independent of the error. However, if the error gets larger, the results would be distorted apparently. Comparison experiments conducted in the present study suggest that the upper limit of potential errors for reasonable results is about 0 5 standard deviations of the original NDVI series. Actual errors are likely to be within this limit, thus the results from the original data are acceptable. In addition, the methods applied in the study can be applied to the similar research to test the significance and robustness of the results in case of unknowing how large the error is.关键词：NDVI;Error;temperature
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发布时间：2021-06-10 - 摘要：The fusion methods such as HIS transform, Brovey transform and principal components transform could merge two optical image data of different resolutions——a high spatial reso lution panchromatic image and a low spatial resolution but multi spectral image. But these fusion methods requie the spectral response range of the high spatial resolution panchromatic image are equal or approximate to that of the multi spectral image. This paper brought forward a new kind of fusion method called Edge Enhancement Intensity Modulation（EEIM） that could merge two optical image data of different spectral characteristics based on solar radiation and land surface reflection model. By using a ratio between a high resolution image and its LOG filtered image, spatial details can be modulated to a co registered lower resolution multi spectral image without altering its spectral properties.This paper put also forward `Difference Matrix Frobenius Norm’ （DMFN） to evaluate difference of color between the EEIM image and multi spectral spectral image, The result of ‘ DMFN ’ showed that value of ` DMFN ’of the EEIM highei than method is less than the Brovey method,and the value of entropy of the EEIM image is higher than the Brovey image. The fused production of EEIM is more excellent at information amount and spectrum preserving.关键词：spectral preservation;EEIM fusion method;remote sensing image fusion
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发布时间：2021-06-10 - 摘要：Through the airborne experiment, a research on the W band Millimeter Wave Radiometer（RADW92） is introduced in this article. Microwave remote sensing images of parts of the Yellow River and the Weihe River were acquired, which were the first batch images produced from scanning W band Millimeter Wave Radiometer in China. The experiment shows that RADW92 is adequate for space use. The analysis of some factors influencing the image quality as well as the solutions to them are included in this article. The RADW92 works with operating frequency at 92GHz,the bandwidth 2GHz,the integration time 60ms, the system sensitivity 0.6K and the linearity better than 0.999. Cassegrain Antenna was designed for conical scanning and imaging. The two images presented in the paper are both original results without any correction. Compared to the reference map,both rivers on the images have the identical trends with the reference maps. The geometrical form of both rivers has distortion to some extent. Many reasons can result in the distortion including scanning track approximation,longitude and latitude approximation, altitude error, velocity and attitude approximation,etc. Moreover, the algorithm of software is also an important factor that affects image qualities. According to that,the observed data for spaceborne imaging should be matched with the parameters of the imaging platform for the geometrical correction.
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发布时间：2021-06-10 - 摘要：Currently the function of operational locust monitoring system mainly focus on after hazards monitoring and assessment, and to find the way effectively to perform early warning and prediction has more practical meaning. Based on two years of 2001 and 2002 continuous field sampling and statistics for 7 phases observation of locusts eggs hatching, nymph growth, adults sample statistics and calculation, spectral measurements as well as synchronously remote sensing data processing,we raise the view point of three stage monitor the locust hazards with Remote Sensing. They are:（1） during the egg hitching phase remote sensing can retrieve parameters of land surface temperature （ LST ） and soil moisture;（2） during nymph growth phase locust increases appetite greatly and remote sensing can calculate vegetation index, leaf area index, vegetation cover and analysis changes; （3） during adult phase the locust move and assembly towards ponds and water ditches as well as less than 75% vegetation cover areas and remote sensing combination with field data can monitor and predict potential areas for adult locusts to assembly. In this way the priority of remote sensing technology is elaborated effectively and to provide technique support for the locust monitor system. The idea and techniques employed in the study can also be used as a reference for other plant diseases and insect pests.关键词：east Asian migratory locust;breading circle;remote sensing 3 stage monitor model
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发布时间：2021-06-10 - 摘要：Over the past 30 years, considerable parts of coastal tideland have been enclosed and reclaimed for agricultural land uses in Zhejing province. The purpose of this work was to evaluate whether the laboratory spectral data could be used to estimate the reclamation levels of saline soils. The northern region of Shangyu City in Zhejiang Province as a study area was divided into four sub zones with different historical years of reclamation. Soil samples were collected from field at approximate 1 kilometer intervals using GPS. Soil physic chemical properties analyzed in laboratory showed that saline soils had low organic matter, high electrical conductivity and sand content, and some soil properties changed with reclamation years. These changing trends of soil chemical and physical properties can be indicated by laboratory reflectance spectra of soil samples. The Person correlation analysis showed that there existed good relationships between nine absorption bands and selected soil properties. Stepwise Discrimination Analysis （SDA） was applied to estimate the reclamation levels of saline soil. The results showed that saline soil with different reclamation years could be classified with an overall accuracy of 86 8% for 68 original grouped cases and 89 3% for 28 cases not involved in SDA according to the Fisher’s discriminant functions. The study suggests that remote sensing should be potentially useful and effective tool to estimate saline soil reclamation, by comparison to the time consumed conventional field investigation.关键词：saline soil;spectral;development;estimation;stepwise discriminant analysis
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发布时间：2021-06-10
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