2005 Vol. 30, No. 1
Traditional point photogrammetry, line photogrammetry developed in the present and the infinite point theory are synthetized and sublined to the generalized point photogrammetry. After the theory of the generalized point photogrammetry is introduced, its applications are presented, including computer of image parameter from vanishing point and modelling by single image, determination of image parameters by matching between vector and image, inspection of sheet\|metal part and determination of plane pose by contour line matching.
Beginning with the analysis of the behavior of natural ants, this paper illuminatest the principle and method that, by adopting image texture energy as pheromone, artificial ants can have the ability to identify and remember something through the similar measurement of pheromone. Then this paper makes a study of the factors which influence the ability of artifical ants and draws some conclusions about the law of artifical ants' perception. These conclusions will be useful for applying ant simulation to image interpretation.
On the basis of the analysis of the methods for single band image texture, this paper presents the concept of multispectral texture applying the relativity analysis of local area and the variant characteristics of multi\|dimensional coding to represent the texture characteristics of the different objects. The experiment result has proved that this method is useful for the extraction of the spatial texture with spectral characteristics.
This paper introduces a linear spectral random mixture analysis model based on ICA. It assumes that the spectral signature of an image pixel is linearly mixed by the spectral signature of independent materials. Experimental results with real imagery data show that the method is effective in multi\|spectral remote sensing image classification.
This paper presents a self\|adaptive algorithm based on prediction, introduces the theory of the algorithm and gives many examples and comparisons. The algorithm computes the mean and std. diff. of current and previous pixels' density to estimate the next point's density range: if the next point's density falls in the range, it is not a boundary point; otherwise, it may be a boundary point. The results show that the algorithm of image boundary detection is more effective than the others.
This paper analyzes three methods for extraction using remote sensing:experience model method,vegetation index method and mixxed\|image analysis method, and advances the model based on vegetation fraction extraction using middle differentiate frank sat image combining high differentiate frank sat image. It is proved that this model is simple and practical.
This paper proposes an optimal mathematical model to represent the surface of hand wrist. First, three\|dimensional photogrammetry is used to take photos of the touched surface of a hand wrist. Then, a system of digital photogrammetry is taken to capture the data from the photos. Finally, the optimal mathematical model is presented to represent the touched surface of the hand wrist. The result may not only show the optimal coincidence between two wrist surfaces to the surgical of hand surgery, but also benefit the make of artificial joint.
Based on the bi\|cubic Bessel spline function method, this paper inverts the present\|day crustal horizontal velocity field and deformation field in China continent by combining GPS velocities obtained by high\|precision GPS network adjustment, seismic moment tensor data and fault slip rates. By this velocity and deformation field model, this paper analyzes the necessity of crustal deformation correction for the geodetic network observations in the joint adjustment of geodetic network and GPS2000 network.
The technique of evaluating CHAMP satellite orbit with SLR Measurements is presented. As an independent evaluation of the orbit solution, SLR data observed from January 1 to 16, 2002 are processed to compute the residuals after fixing the GFZ’s post science orbits solutions. The SLR residuals are computed as the differences between the SLR measurements minus the corresponding distances between the SLR station and the GPS\|derived orbit positions. Based on the SLR residual analysis, it is found that the accuracy of GFZ’s post science orbits is better than 10 cm and that there is no systematic error in GFZ’s post science orbits
This paper states the methods for establishing a 1'×1' digital model of the vertical deflection and presents the data . The results of precision estimation in both the prime vertical component and the meridian component for this model achieved through adapting the 1 489 high\|accuracy astro\|geodetic points as check points are: ±0.94″ and ±0.99″ for the eastern region, respectively, ±1.71″ and ±1.28″ for the northwest region, respectively, ±1.95″ and ±2.00″ for the southwest region and the general precision for the whole country is better than ±1.5″. Generally, the determination of the vertical deflection on any point using the model and its corresponding software can be realized within 2 seconds.
According to the topography\|isostatic theory, an isostatic\|geoid can be calculated; at the same time, the model\|geoid can be derived directly from earth's gravity field model. In this paper, the "remove\|restore" technique and multi\|quadratic function are used to interpolate the known GPS/leveling data. The experimental results show that the accuracy of simulated geoid by practical geophysical data is better than other geoids.
This paper puts forward three CA models: expansion\|based state CA model, axis\|based traffic CA model and advantage\|based environment CA model, designs six conversion rules:surround filling,expansion growth,transportation extension,transportation conection,transportation atraction and advantage growth. The simulating results shows that the urban spatial growth is presenting the tendency of growing into an organic whole from urban to subur
In data grid, how to access data is the key problem of application metadata management and replica metadata management. To resolve the problem, this paper proposes a metadata classified management mechanism(MCMM for short) based on data grid that defines a data model and an application metadata schema and applies different storage methods to different metadata, and MCMM designs a guide\|based query intelligence entity.
A criterion of shape similarity between line segments is presented, which meets rotating invariance and translation invariance. The method is ease in calculation and fit for clustering analysis of geographical area entities. An algorithm of calculating shape similarity between line segments is put forward. The influence of different parameters on criterion results is analyzed.
The mathematic theories for uncertainty model of line segment are summed up to achieve a general conception, and the line error band model ε σ is a basic uncertainty model that can depict the line accuracy and quality efficiently while the model of ε m and error entropy can be regarded as the supplement of it. The statistical characteristic of the line error is developed deeply by analyzing the probability that the line error falls inside a certain range. Moreover, the theory accordance is achieved in selecting the error buffer for line feature and the error indicator. The relationship between the accuracy of area for a polygon and the error loop for a polygon boundary is deduced and computed.
This paper presents a model for designing both the two\|dimensional movements of objects in a map and the variation of map window. By using this model, most proposals can not only be drawn on a map, but be made into demos. Some key technologies and an instance for improving the speed of such a system are given
Software reuse and functional component assembling are two main goals of GIS software development. Some design patterns which have been applied to the functional component compartmentalizing, components organizing, component assembling are described in detail. A practical running system which has been implemented is also given to demonstrate the efficiency of the research.
This paper discusses the conceptual clustering and technology of attribute\|oriented induction through analyzing the present situation of the regional division studies and combines them in regionally dividing the agricultural products of a certain place.
This paper investigates the geometric 3DCM,sunlight models,and is concentrated on three key problems displaying shadows of building,calculating sunlight hours,calculating sunlight interval distance.This paper also implements the arithmetic function of sunlight analysis,and gives out some simulation and experimentation results.