1. INTRODUCTION  
2. SAMPLE SELECTION  
2.2. Potential for High-mass Star Formation  
3. OBSERVATIONS AND DATA REDUCTION  
4. RESULTS  
4.1. Dust Continuum Emission  
4.2. Core Identification  
4.3. Core Physical Parameters  
4.4. Identification of Hub-filament System  
5. DISCUSSION  
5.1. Core Mass  
5.2. Most Massive Cores  
5.3. Early Phase of High-mass Star Formation  
6. CONCLUSION