Table 4.
Results of TF-IDF analysis

Problem		Site		Solution
Word	TF-IDF	Word	TF-IDF	Word	TF-IDF
Particular matter	24.72	City	34.93	Analysis	20.39
Concentration	21.31	Park	28.33	Plan	18.52
Environment	18.94	Area	25.06	Evaluation	12.64
Carbon	14.48	Green area	19.09	Development	11.72
Atmosphere	14.17	Space	13.77	Management	11.33
Emission	13.05	Area	7.25	Impact	10.67
Climate	9.39	Forest	6.76	Utilization	10.39
Measurement	9.27	Planting	5.94	Facility	9.77
Pollution	9.15	Green	5.49	Ecology	9.60
Dust	9.02	Road	5.47	Policy	9.53
Occurrence	7.17	Nation	5.43	Green infrastructure	9.06
Substance	6.54	Recycle	5.32	Reduction	8.97
Fine particular matter	6.20	Nature	5.04	Technology	7.61
Energy	6.19	Street tree	4.50	Resilience	7.30
Land	6.19	Ventilation Corridors	4.50	Element	7.24
Disaster	4.712	Network	4.44	Landscape	6.97
Wind speed	4.63	Garden	4.23	Function	6.77
High concentration	4.51	Roof	3.95	Sustainable	6.03
Greenhouse gases	4.33	Building	3.81	System	5.41
Pollution Source	3.26	Buffer	3.62	Connection	5.27

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