Then an optimization model of a single goal is set up, with the application of the gray method of prediction to predict the sales volume of the unit book number.
第二步建立一个单目标的优化模型，运用灰色预测的方法预测出单位书号的销售量。
2
The first stage, performed by the extraction unit (110), employs an analysis of gray values of the image data in order to extract the candidate region.
由提取单元（110）执行的第一阶段使用对图像 数据灰度值的分析以便提取候选区域。
3
He said many Chinese buyers still prefer to buy an HTC handset on the gray market, which may be at least 500 yuan cheaper per unit.