Research On The Necessary Accuracy Of Real Estate Measurement And The Solution Methods Of Coordinate Transformation Parameters

With the implementation of the unified real estate registration system in our country, the key technology and standards of the real estate surveying and mapping will be more perfect. Real estate surveying and mapping is the principal means of access to data information, having the force of law, which is the foundation source of national construction and the government decision-making. The job to Study on the required accuracy of estate measuring and the Solution of coordinate transformation parameters is an important basis for the real estate mapping and can provide basic guarantee and support for real estate unified registration. At the same time this study can promote the rapid development of real estate unified registration, effectively restrain and standardize the real estate industry competition, safeguard the interests of the people, fully embody the value of real estate itself and provide reliable basis data for the country.This paper studies the common several kinds of real estate, including the real estate surveying and mapping, cadastral surveying and mapping, underground space, the right to the contracted management of land measurement, the sea, grassland and forestry measurement, they have different measuring content, measuring coordinate and accuracy requirements. Generally shows the measuring accuracy of land and housing in the national standard regulations detailed compared with other categories of real estate and each property measurement coordinate in the form of diversification.This article focuses on the necessary precision of real estate survey and the solutions of coordinate transformation parameters. First of all, it puts forward the concept of necessary accuracy based on the demand for property management and real estate value demand. And to build a model, which can provide real estate choice of precision in the measurement method, by using the analytic hierarchy. Secondly, in order to achieve the goal of real estate data sharing and real estate a diagram, the precision of the coordinate transformation is to meet the requirements of the necessary precision. In this paper, coordinate transformation parameters solving method are studied, and a new method, combined with the drop weight and total least squares method which can improve the solution precision, is put forward to solve the parameters of the coordinate transformation.The keys of the transformation of different coordinate data are to choose appropriate settlement transformation model and solving the model parameters. Plane coordinate transformation system, which can realize the data transformation of different coordinate, was designed and developed. Finally, the drop weight total least squares method applied to calculating parameters can achieve higher precision through two examples.