the enterprises apply changes in accounting estimation to earnings management,accounting report fraudulence,and even profit manipulation,which will cause serious economic consequences and damage relevant person s interest.

This?paper tests market efficiency through examining its capability to identify the essence of change in accounting estimate.

The concepts of accounting policy change, accounting estimate change and accounting error correction are often encountered in accounting practices.

To solve the problem of design change of auto panel dies,the integrated information in different developing stages of auto panel dies is firstly analyzed.

Their are effective measures of costs control for mountainous expressway construction,such as aborative design,enhancement of follow-up service of design,strengthening of management for design change,positive cooperation among all the participants of the construction,strictly controlling of design change.

Due to the start of construction in a hurry,some design changes and optimization have been made after the start of project construction,such as increasing the rated head of unit,adoption of gravity dam connecting with two banks,using GIS for switchyard equipment,river closure ahead o.