Active duration的用法和樣例：
例句
- To maximize concurrency in a program, we must minimize the frequency and duration of lock acquisition.
為了使程序中的併發效用最大化，必須最小化鎖定獲取的頻率和時長。 - On one hand, your creativity may be challenged by the lack of autofocus, the limited shot duration and the enormous file size.
一方面，你的創造力可能會因自動對焦的缺陣，會因有限的拍攝時長和龐大的文件體積而受到挑戰。
