A TENSOR ANALYSIS METHOD FOR ESTIMATING 3-D MOTION PARAMETERS

By using the center projection image sequence to estimate 3-D motion parameters,one needs to know the corresponding relationship between the feature of motion object in spaceand the projection coordinate on image plane.In order to avoid using the relationship of featurecorrespondence,the tensor analysis method in the affine transformation system is presented,andthe simulation data of experimental results are given.

3-D fracture network dynamic simulation based on error analysis in rock mass of dam foundation

Accurate 3-D fracture network model for rock mass in dam foundation is of vital importance for stability,grouting and seepage analysis of dam foundation.With the aim of reducing deviation between fracture network model and measured data,a 3-D fracture network dynamic modeling method based on error analysis was proposed.Firstly,errors of four fracture volume density estimation methods(proposed by ODA,KULATILAKE,MAULDON,and SONG)and that of four fracture size estimation methods(proposed by EINSTEIN,SONG and TONON)were respectively compared,and the optimal methods were determined.Additionally,error index representing the deviation between fracture network model and measured data was established with integrated use of fractal dimension and relative absolute error(RAE).On this basis,the downhill simplex method was used to build the dynamic modeling method,which takes the minimum of error index as objective function and dynamically adjusts the fracture density and size parameters to correct the error index.Finally,the 3-D fracture network model could be obtained which meets the requirements.The proposed method was applied for 3-D fractures simulation in Miao Wei hydropower project in China for feasibility verification and the error index reduced from 2.618 to 0.337.

THE GENERALIZED VECTOR METHOD OF QUANTITATIVE TEXTURE ANALYSIS

The vector method (VM) of quantitative texture analysis has been entirely reconstructedin the Euler space using Roe’s notation. The reconstructed VM, called the generalized vectormethod (GVM), has got rid of the limitations arising from the original form of orientationrepresentation of the VM, such as the inconvenience in searching the relation between tex-tures and physical properties of materials, and conserves all the advantages of VM. The investigation on a cubic crystal system indicates that the texture vector of a samplemay be quantitatively determined with the GVM, using a complete or even an incompletepole figure. Also, the series expansion coefficients of the crystallite orientation distributionfunction (ODF) needed in calculating macroscopic anisotropies of the sample can be easilyevaluated.

Thermal Simulation of AC Electromagnetic Contactor

Transient magnetic circuit method is adopted to calculate the power loss in winding and shading coil. Based on the analysis of heat transfer process in AC contactor, a thermal model is proposed and the temperature field distribution is simulated with 3-D FEM of ANSYS. Comparison of simulation results with measurements shows that the proposed method is effective.

TRAJECTORY ANALYSES OF THE DUSTSTORMS OVER EAST ASIA

The transports of dust are calculated using 3-dimensional(3-D)trajectory method for three cases of duststorms in the terrain-following coordinate system,and the synoptic processes are also discussed for each case.The case of 17—20 April 1980,a severe duststorm was associated with the rapid development of a cyclone over the Mongolia Plateau.The dust moved from west to east across several deserts,formed a typical dust path in spring.The other two were weaker and the dust was triggered by the strong wind behind the cold front from northwest or north.Because the vertical velocity is considered in 3-D trajectory analysis,trajectories calculated should better reveal the transport rule of the dust particles and the results seem to be more consistent with the synoptic processes.The trajectory analysis on the 2-D isobaric sur- faces is simpler but can be used only in the conditions with weak vertical wind shear and weak vertical velocity.The dif- ference of trajectories at lower levels between two methods may be caused by the different treatment of orography.