I'm officially in what organizers are calling the closed loop.

我已经正式进入了奥组委所说的闭环系统了。

It feels like testing Ava through conversation is kind of a closed loop.

感觉通过对话来测试艾娃是一种闭环。

Since the circulatory system is a closed loop, cardiac output and venous return are equal.

由于循环系统是闭环，心输出量和静脉回流血量是相等的。

To improve its tracking of purchases, Facebook is moving to create a closed loop of its own.

Facebook正着手建立自己的闭环以改善对用户购买行为的跟踪。

These strings may have ends (the so-called open strings) or they may be joined up with themselves in closed loops (closed strings) (Fig.

这些弦可能有末端（所谓的开弦），或者它们可能以闭环（闭弦）的形式与自身相连（图 1）。