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| 跟踪与数据系统 | |||
| 跟踪和数据系统 | |||
| tracking and data system: 20 phrases in 8 subjects |
| Air defense | 3 |
| Aviation | 2 |
| Earth sciences | 3 |
| Electronics | 4 |
| Information technology | 1 |
| Space | 5 |
| Technology | 1 |
| United States | 1 |
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