短语词组短語kernel preemption 內核搶佔non preemption 不可搶佔symbol preemption 符號搶佔capacity preemption 資源剝奪Preemption Rights 優先購買權法Preemption Po 搶佔點Preemption Mechanism 搶佔機制preemption penalty 中斷損失 返回 preemption