1996 Vol. 21, No. 1
On the basis of the pseudo-solution theory on overdetermined boundary value problem,the pseudo-solution to satellite gradionietry boundary value problem is derived in the paper. And its solution is reduced to solve a group of linear-banded equations.Moreover,the even degree and odd degree potential coefficients are separated and computed conveniently.
Several aspects of the application of satellite altimetry in physical geodesy are summarized. The mathematical models and principles for approximation of the earth gravity field, the determination of the sea surface topography, the improvement of satellite orbit parameters and the evaluation of gravity anomalies are described.
In this paper,a new method is presented for reducing the equations of motion of a slightly elliptical symmetrical elastic Earth model to spherical domain. The equations obtained are just that of a spherically symmetrical elastic Earth model plus elliptical correction terms.
Mathematic models of instantaneous sea level for single,double,three and more tide stations are discussed respectively in this paper. Based on the various hypotheses about tidal propagating characteristics, the linear interpolating method,harmonic constant method and least square fitting method are studied in detail,which are verified with real observation data.
This paper studies the determination of datum station with GPS and the computation problems of the sound pulse signal received by the datum station of echo pulse receiver under water. It is proved that the model and the methodology advanced by this paper can not only compute the observation of mulitiple system with gross error, but also have better quality in tracking and computing the moving target red than the old ways.
By analyizing the limits of GM(1,1)forecasting model,this paper gives a new method,which integrates dynamic forecasting method with recent information and recursive compensations by grey numbers of identical dimensions. This method has been applied to the Lianzi Cliff deformation dy monitoring and prediction with proved efficiency. The analysis showed that the Lianzi Cliff is currently in the stable developing mode.
This paper presents two types of function models of successive adjustment with restrictive conditions keeping in mind the large geodetic network.The adjustment formulae about the two types of function models have been inferred by applying the theory of successive adjustment and the principle of correlative least square.
This paper discusses applications of mathematical morphology in GIS spatial analysis. The new method based on morphological transformations is presented, which includes overlay, buffering, proximity, measurement as well as optimum route of network and visibility analysis.
Recognition of point-shaped map symbols with use a new neural network model is expounded in this paper. The structural characteristics of the network,the learning algorithm and the process of studying and training are discussed as the principal research contents. Experiments have proved the efficiency of this network in recognizing point-shaped map symbols.
in this paper,we first discuss some image mosaic methods and analyse their shortcomings,and then present a new image mosaic method based on whole adjustment according to the principle of photogrammetry.Experiment shows that this method has unique advantages:a high degree of automation,direct use of interesting points on the image,a high accuracy and free size of maps.
Based on the setting up of the function relation between the radiant brightness of ice-surface and the elevation control point in Antarctica, the experiments for the extraction of elevation information by using Landsat TM band 6 thermal infrared image, and the ice-surface topographical mapping in Antarctica have been performed.
Based on the fractal theory,a new method of automatic generalization of map polygons is proposed in this paper,which can automatically generalize the map polygons according to the distribution characters and shape features themself.
Information variation of map elements can be measured with information method. Based on this principle a mathematical model used in determining varied information content of map is established. Through an experiment, the result obtained by using this model is proved to be well consistent with the actual variationon the map.
Based on the theory of cartographic algebra, the settlement compilation technique was designed and practised. The conclusion is that the cartographic algebra system is superior in technology,efficiency and quality,compared with the conventional copspilation technique.
This paper presents the method for describing CRT (Cathode-Ray-Tube) monitor input/output color property by means of the monitor characteristic function and characteristic matrix, develops the mathematic models relating CRT monitor digital drive values with display color tristimulus values.
The Moire effects of CCD-image sensors are studied,and the equation for optical transmission characteristics of Moire fringes is presented in this paper.The measurement of Moire fringes can be obtained when some conditions are satisfied.The experiment results show that the new method is simple and practical,and it is then easy to realize automated processing.
Fuzzy querg usually includes fuzzy words and three kinds of modifiers:linguistic, fuzzy as well as deterministic modifier.All these can be described with fuzzy set theory.To this end,this paper presents an approach for representing fuzzy query via Extended SQL(ESQL),which is then implemented by being transferred into standard SQL.
We successfully connected three programmable logic controllers with a microcomputer by using serial communication technique,setting up a distributed control system.This paper introduces the hardware structure and software designing ideas of the system.