1 Subjects: “...outdoor air quality factors...”

2 Subjects: “...non-negative matrix factorization...”

3 Subjects: “...matrix factorization...”

4 Subjects: “...shape factor...”

5 Subjects: “...influencing factors...”

6 Subjects: “...factor analysis...”

7 Subjects: “...influencing factors...”

8 Subjects: “...multivariate factors...”

9 Subjects: “...profitability-influencing risk factors...”

10 Subjects: “...risk factors...”

11 Subjects: “...critical success factors...”