The leading factors of soil ecosystem in arid area are discussed based an the application of the principle and method of grey relational gradation, the important part of grey system theory.

Application of grey relation analysis to reservoir evaluation-taking Bei 2 area, Saertu oilfield, Daqing as an ex- ample;

Fuzzy synthetic evaluation and grey relation analysis of economic strength of main city in China;

Grey Relation Analysis of the Relationship between Agricultural Production Structure and Farmers Income in Anhui Province;

Performance evaluation of complicated product based on grey relational analysis;

Optimization and selection of air-conditioning heat andcold sources based on grey relational analysis;

Application of grey relational analysis to judging the type of fault-phase in transmission line;

Gas logging interpretation method of oil-gas potential reservoirs based on grey correlation analysis;

The grey predicting and grey correlation analysis of city road traffic noise pollution;

Design scheme evaluation of an attacking system based on grey correlation analysis;

Assessment of urban ecological security based on entropy-weighted gray correlation analysis;

Application of gray correlation analysis on regional agriculture leadingindustry adjustment strategy of Guyuan county in Bashang Plateau;

Several Decision-making Methods Based on Gray Correlation Analysis and Their Applications;