birr

1. In order to overcome slow convergence rate of the standard BP algorithm, this paper presents an adaptive backpropagation algorithm which can update learning rate and birr factor automatically based on dynamical training error rate of change.
   本文针对BP算法存在收敛速度慢的缺点，提出一种基于网络动态训练误差变化率自动校正学习步长和冲量因子的自适应反向传播算法。
2. BIRR Model and the Use of a Macroeconomic Factor Model in China's Stock Market Macroscopic Observation
   宏观因子套利定价模型的因子筛选及在中国股票市场的应用

noun

1. sound of something in rapid motion
   1. whir of a bird's wings
   2. the whir of the propellers

   Synonym:    whirwhirrwhirring

2. the basic unit of money in Ethiopia

verb

1. make a soft swishing sound
   1. the motor whirred
   2. the car engine purred

   Synonym:    whizzwhizwhirrwhirpurr