Applied Mechanics and Materials Vols. 353-356

Abstract: In the CFD(computational fluid dynamics) study of hydrocyclones, the grid is a important factor to predicting the flow field. An attempt has been made in this study, in the same turbulence model and boundary conditions, three different structures of grid, the structured grid, the unstructured grid and the hybrid grid, are compared for the predictions of the axial, radial and tangential velocities. It has been observed that the memory space structured grid is large, and there are much number grid of the unstructured grid. The structured grid led to an improved turbulence field prediction and thereby to predict the velocity fields of single phase flow field more accurately. The unstructured grids is used to simulate the process of oil-water separation.

Abstract: As a burgeoning survey approach, 3D laser scanning is currently more and more applied in traditional architecture survey. In the surveying practice for Tianwang Hall of Hangzhou Haichao Temple, by skillfully setting the targets, we efficiently and accurately collected relevant surveying data with 3D laser scanner. On this basis, utilizing jointed point clouds on inner and outer surface, we successfully obtained wall thickness, roof depth, and other data that could not be precisely captured through traditional surveying measures. Moreover, the width, height and size of main beams were also easily and accurately acquired. So far, 3D laser scanning has become a very effective measure in traditional architecture surveying.

Abstract: Using Chebyshev polynomial to fit precise ephemeris of GPS, the nodes selection has a certain influence on the precision. In this paper we use 3 kinds of precise ephemeris ( IGF, IGR, IGU ) to analyze the difference precision of randomly selected interpolation node and Chebyshev points fitting orbit and compare the difference and precision of fitting orbit by 3 kinds of ephemeris and orbit provided by IGS. The result shows that using Chebyshev points to fit precise ephemeris, the precision of IGF and IGR can achieve mm levels, the precision of IGU can achieve cm levels.

Abstract: In a complicated leveling-network, it was often simple to write manually the equations to express all the condition that must be met for a conditional adjustment. Therefore conditional adjustment which was straightforward and regularity in its development and solution.was early becoming very popular . But with the advent of the computer technology, it was gradually reducing its effects which was not well suited to computers for its equations not unique and shapes diversity. Based on this, an available leveling-network conditional adjustment program was developed to solve the problem of conditional diversity. By aid of transferring matrix, the program design scheme of the conditional adjustment was proposed by means of visual basic language platform. The coefficient matrix of the conditional equations was written out based on transferring vectors and arithmetic rules. The normal equations were solved by method from Guassian main column eliminated. The Residuals and the measuring precision was achieved by the results from the normal equation back substituted to conditional equation. The application shows that conditional adjustment by transmitting matrix can simplify procedure of writing the conditional equations, and easily program for conditional adjustment.

Abstract: In order to separate effectively small deformation from GPS signal containing the error, Based on multiwavelet theory, the paper makes DGHM for GPS deformation monitoring signal processing, because the DGHM biorthogonal wavelet is with short support, orthogonality, symmetry ( antisymmetry ) and two approximation and other characteristics, in the same length of filtering, multi-wavelet method is more superior than traditional wavelet method, improves the signal to noise ratio, obtains higher accuracy, confirms correct and practical in the actual problem, the algorithm has opened a new way for deformation monitoring signal processing

Abstract: This article introduces the application of measuring robot in the open mine slope monitoring, and it proves its feasibility via analyzing the monitoring data and measuring accuracy. It indicates that TM30 measuring robot is able to finish the measuring task with high accuracy by the practical application. Therefore it concludes the measuring of operating items.

Abstract: The research of variance-covariance propagation of nonlinear least squares adjusted parameters must keep pace with the development of nonlinear least squares adjustment. In this area, the existing result is inclined to the variance-covariance propagation of observation value, and the nonlinear least squares adjusted parameters precision is seldom concerned. This paper gives a variance-covariance propagation of nonlinear least squares adjusted parameters for different types of data and its calculating formula. The results of example prove that the method is effective and reliable.

Abstract: In this paper a hybrid genetic algorithm which consists of the simplex method and the genetic algorithm is proposed for the defect of poor local search ability of genetic algorithm. The hybrid genetic algorithm has the advantages of good global convergence of the genetic algorithm and excellent local search ablility of the simplex method and can improve search speed and calculation accuracy.The hybrid algorithm is applied to the control network adjustment and experimental results demonstrates the effectiveness and superiority of the algorithm.

Abstract: In this paper, the relationship between zenith tropospheric delays and the altitude of stations is analyzed using the EGNOS tropospheric correction model. The new model (EHT model) is proposed for estimating zenith tropospheric delays from regional CORS data without meteorological data. The proposed model is compared with the direct interpolation method and the remove-restore method using data from Guangxi CORS. The results show that the new models significantly improve the calculated precision.

Abstract: The paper points out that the figure symbol “ ” should be named as “double zero”, not infinity. “ ” has the similar meaning as “0”. They all express no numerical value. In this paper, the application based on the definition above in probability theory is discussed.