現在科技不斷的朝多核心方向發展，從早期在個人PC上發展多核心到智慧型手機也開始裝載多核心，反映出多核心系統越來越貼近生活，尤其多核心系統較單核心系統有較優的運算能力，能提供越來越大量資訊運算的需求。
當多核心系統運用越加廣泛，勢必面臨電源功耗提高及耗電快的事實，特別是智慧型手機，擁有越多功能、支援多媒體、影音…等，耗電的問題就愈發嚴重，故能源問題已是現在科技發展必須面對的十分重要的課題。
本論文提出一個方法能達到降低電源功耗的目的，同時在降低耗能的過程中更能兼具可靠度，本論文利用離散頻率的特性，將工作分成兩種頻率執行，並保證能在期限內完成的前提下降低其執行速度以達到降低電源功耗的目的。實驗結果顯示本論文所提出的方法能有效降低電源功耗又能兼具系統的可靠性。

Technology is continuously developing towards the direction of multi-core systems. Power consumption is an important issue of embedded multi-core applications when green computing is considered. In this thesis, we introduce an energy-efficient algorithm for scheduling periodic real-time tasks in multi-core systems, which can reduce the power consumption and maintain the reliability of systems. Simulation results show that our algorithm can reduce power consumption ranged from 6% to 10% and 20% to 27% in periodic real-time systems, compared to RA-DPM and Greedy, respectively.

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