pi

英 [paɪ]

美 [paɪ]

n.  圆周率; 希腊字母表的第16个字母

复数：pis　

计算机

BNC.8364 / COCA.18727

牛津词典

noun

• 圆周率
  the symbol π used to show the ratio of the circumference of (= distance around) a circle to its diameter (= distance across), that is about 3.14159
• 希腊字母表的第16个字母
  the 16th letter of the Greek alphabet (Π, π)

柯林斯词典

• 圆周率（通常用希腊字母�表示，近似值为3.142）
  Piis a number, approximately 3.142, which is equal to the distance round a circle divided by its width. It is usually represented by the Greek letter �.

英英释义

noun

• the 16th letter of the Greek alphabet
• the ratio of the circumference to the diameter of a circle

双语例句

• Net Search Extender supports comment nodes ( example 3 in Listing 30) and processing-instruction ( PI) modes.
  NetSearchExtender支持评论节点（清单30中的示例3）和处理指令（PI）节点。
• The test results show that it has better performance both in dynamic and steady state than traditional PI control.
  此方法计算量小，实验证明获得了较传统PI控制更好的动静态性能。
• We want to discuss sigma bonds and pi bonds.
  我们要讨论sigma键和π键。
• The controller consisted of a PI feedback controller and a self-adaptive DRNN feed-forward controller.
  反馈控制器以目标转速与实际转速的误差为输入量，采用PI控制来提高控制系统的稳定性。
• Research of Hybrid Excitation Claw Alternator Control System Based on Fuzzy Self-adaptive PI
  基于模糊自适应PI的混合励磁爪极发电机控制系统研究
• The model of speed loop control system as well as the integral separating PI controlled algorithm was analyzed in detail.
  对控制系统建模和积分分离PI算法进行了详细的分析。
• PI/ HO33342 double staining could distinguish apoptotic cells as well as normal cells;
  PI/HO33342双染可区别凋亡、坏死和正常细胞，且可以见到染色质碎裂；
• The inner loop adopts PI algorithm and the outer loop adopts a time optimal self-tuning PID algorithm.
  伺服控制器分别采用有源PI校正和时间最小参数自调整PID控制算法。
• However, PI and square root are a bit more common.
  然而，PI和平方根比较常见。
• PI controller is widely used in wind turbine control system and its parameters need to be identified.
  风电机组控制系统中PI控制器较多，需要辨识各PI控制器的参数。