The objective of the study (Zhejiang province as our test region) was to investigate how to utilize synthetically a wide variety of geographical information,included topographic map,vegetation map,land cover/use map and other ancillary information,for estimating rice planting area of hilly region in southern China by remote sensing technique with NOAA/AVHRR data.The research contents mostly concerned both the contrast tests on practical approaches and the relative stability test on training sample.Both DEM and digital slope imagery derived from the digital relief map were used for the purpose of improving the classification accuracies of AVHRR data in large hilly region.The results indicated that the accuracies of maximum-likehood classification could satisfy the professional requirement of estimating rice planting area and fuzzy supervised classification based on unmixing AVHRR imagery has better classification and stability than MLK.In addition,the results through using DEM and slope imagery as categorization data suggests slope imagery may improve the results of extracting paddy field signatures from AVHRR,particularly may improve the spatial precisions,while DEM contribute nothing to improve the accuracies mentioned above.The results also indicated that the precisions of estimating rice planting area with relative stable training sample exceeded 92%,up to 98%.
In this paper, the design of Snow Monitoring and Application System (SMAS),through the integration of existing relevant commercial software with object-oriented programming technology,including the system conceptual structure,logical structure and realization methodology were described.Also,the applied models and parts of their results were presented.Brief evaluation of this system was given at last.
In the present article the feasibility of estimating the gas transfer velocity across airsea interface in terms of microwave backscatter is explored by combining two computation methods proposed or adapted previously by the authors〔1〕. The predictions of gas transfer velocity in terms of microwave backscattering was compared with the simultaneous measurement data of gas transfer velocity and microwave backscatter obtained by Wanninkhof and Bliven〔2〕in Delft big wave tank. Satisfactory comparison results were obtained. Usage of the present computation methods in making prediction has advantage of greater flexibility over empirical correlation like those in〔2〕, as the proposed approach is less dependent on the working frequency of the microwave instrument and various data sources of gas transfer and microwave backscatter measurements can be utilized to improve the prediction.
It is undoubted there are some interdependent relationships between rock and soil,on either their compositions or spectrum.The paper analysis lab.reflectance spectrum(0.4～2.5μm) of soils and their parent rocks from the Western Qinling area.In the respects of spectral evolution of parent rocks and soils,during different weathering period and between different soil layers,also the effect of organic and ferric oxide matter to spectrum are discussed.It is important for remote sensing to identify the underlying rock and alteration,through spectrum of their soils.
The received channel about spaceborne microwave imaging instrument,a microwave radiometer,is the kernel section of space-borne microwave imaging instrument.The key and foundation of simulative study is the method of signal processing.The mathematical model of every section is given.The mathematical means of discrete Fast Fourier Transform is used in signal processing.The contradiction of frequency resolving power and the number samples by discrete Fourier Transform is analyzed and relieved.To take the totalpower microwave radiometer for example the simulative study has been done and the result is given.These lay a foundation for the advancement of realizing system and environment debugging.Also these give a reference to the simulative study of other type of microwave radiometers.
This paper describes a project that the earth can be observed in the staring mode with the high-resolution solid-state imaging device in the geostationary orbit,analyzes the geometric relations when the sensor operates in the staring mode,and according to the current solid-state imaging devices,gives two kind of sensor designs employing 5 000-by-5 000 elements CCD and 1 000-by-1 000 elements infrared FPA,similar to VHRR and GOES-9 in performance.The analysis results indicate that it is a very attractive project in the meteorological and ocean remote sensing to observe the earth in the staring mode in the geostationary orbit.
The image of forest fire monitoring from polar orbiting meteorlogical satellite receiving and processing system is a kind of pseudo color image synthesized by multi-channel data.It reformed by picture encoding and data compression,then was converted into common picture format that can be recognized and displayed on PC.Depending on the computer network,the system enable remote users to attain the picture files,process and show them on terminal.This paper involved some contents such as picture encoding,picture conversion and display etc.
This paper discussed a speckle suppressed and reduction technology for SAR images and analysis characteristic of many speckle reduction algorithms.Comparing advantages and defect of different algorithms and proposed a speckle reduction in multiscale and multi-orientation by using nonlinear wavelet analysis is one of very significant directions.
By fusing ADEOS AVNIR panchromatic channel(PAN) with 8m resolution into its multispectral channel(XS) with 16m resolution,it is possible to produce a high resolution image suitable for photo integration.The principal component analysis(PCA) method has been tested in order to produce color composite image with a high spatial resolution using ADEOS AVNIR' s multispectral mode(16m,four channels) in combination with its 8m panchromatic mode.The fusion process involves two steps:1)Geometric calibration of the AVNIR XS data and PAN data.the geometric error is less than one pixel size(<8m);2) Conducting principal component analysis and reverse principal component analysis to merge the XS and PAN data.Both visual interpretation and statistical index(i.e.Minmax,mean,median,standard deviation and information quantity) are applied to analyze the fusion effect.The results show that the rich multispectral content are maintained after fusion while the spatial resolution increased.
We call Remote Sensing Process software,Geographical Information System software and Relational Database software which capture,store,analysis and process geographical information as Geographical Information Engineering software.This article analyzes the characters of those three kinds software,compares their commercial models which were often used,and put forward an Client/Server based Geographical Information Engineering software architecture to integrate those software together.We suggest two methods of integration model——metadata based and API(Application Programming Interface)based.Metadata based integration model can reach file level integration,it is suitable for current systems based on commercial Geographical Information Engineering software integration.API based integration model can reach object level integration and stands for the future of Geographical Information Engineering software integration.
This paper presented application of geographical information system(GIS)on marine environmental impact assessment.In Dalian bay,GIS technique was used to solve the problem of marine resource utilization and environment protection by developing and utilizing marine resource information.It is in detail introduced that model is linked with spatial data by programming script of macro language of Arcview.
The paper divides the period of monitoring natural disasters and assessing their damage using remote sensing between 1970 and today in China into four stages.The first one is the 1970s,called the starting stage;the second is the 1980s,called the developed stage;the third is from 1991 to 1995,called the further developed stage;and the last is between 1996 and today,called the operation stage.The characters of each stage are described and the work that The Chineses Academy of Sciences has done is introduced,and also the problems that should be solved in the near future are presented in the paper.
