A New Calculation Method of Environmental Similarity

The environmental similarity in this study is the special part of ships' ballast water risk assessment of environmental similarity in ships' ballast water risk assessment. The environmental similarity refers to the degree of similarity between two or more ports. For the study of ships' ballast water, the main consideration is the degree of similarity between the port seawater, in the process of the degree of similarity to the seawater, choosing temperature, salinity, pH, DO, DIN, DIP to calculate the environmental similarity. Firstly, the two calculating environments similarity methods (angle cosine method and based on the concept of ORDR (overlap ratio of data ranges) environmental similarity calculation method) are described and discussed. And analyze their problems. Then, propose a new method for calculating the environmental similarity.