Cost Index System Building And Application Research Of Overhead Line Engineering Based On Big Data

The production, sharing and application of data is a big problem to be solved in the "big data" era. Construction process is relatively complex because of its broadly dispersed construction spot, and complex cost indexes. Large quantities of overhead line project cost indexes are lost because valuable data couldn’t be well classified and induced, which prevents the accumulation of basic data and greatly reduced the accessibility of data. It becomes a vital topic for the construction cost specialty to classify and integrate the existed data for the formation of project cost information platform where varies construction roles can query and use "big data"This paper studies the transmission line index system and its application in cost estimation stage based on the perspective of owners and "big data" theory, combined with total cost management concept and work breakdown structure, for the sake of accumulation of transmission line data. This paper systemizes the transmission line management which provide the guidance to design optimization, budget preparation, project bidding, contract settlement. What’s more, it promotes cost information management of overhead line project to the direction of "big data" and "cloud computing".Prediction is core issue of "big data", that is, the possibility of change and development of events is measured by massive data based on the mathematical algorithm. The foundation of cost index system is the process that varies indexes in need are collected in different cost estimate stages, the completed engineering database is not only a "big data set", but is also the "cloud computing" foundation of transmission line indexes case-based reasoning system.This paper establishes the case-based reasoning system and designs the prediction model of transmission line indexes of transmission line projects. The case-based reasoning system consists of four parts. The first is the representation and organization of cases, which demonstrates the characteristics of transmission line in the form of "groove".The second sub system is the calculation of the weights. This part introduces "box plot" in SPSS software to denoise and calculates the weight vector using the correlation coefficient matrix. The third part is the sub system of cases retrieved:for the primary retrieved, retrieved rules based on knowledge guided strategy should be set by using C++.net language; for the senior retrieved, the similar degrees metric between target cases and case library should be measured by using Weighted Euclidean distance, then retrieved rules based on recently adjacent strategy should be set by using C++.net language. The fourth sub system is the management of cases, case library should be updated and maintained to make research results more timelier. Storage, statistics, analysis and dynamic query of completed project cost information by computer technology, can realize the whole process, all-round, and full team cost control of overhead line construction projects.