Table 5.
Variables’ range and levels.
| Variable | Symbol | Unit | Range and Levels | ||
|---|---|---|---|---|---|
| Low (−1) | Middle (0) | High (+1) | |||
| DPF | D | % | 1 | 2 | 3 |
| Silica fume | F | % | 5 | 10 | 15 |
| Temperature | T | °C | 200 | 400 | 600 |
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.