Uniformity index n represents the range of fragment size distribution and it is applied to evaluate fragment size by Rosin and Rammler cumulative distribution function for a muck pile. The uniformity index n of fragment size distribution has been assessed by digital image analysis technique using Split-Desktop for several blasthole parameters and different zones of in-situ rock mass conditions in five mines having a wide range of blastabilty index (BI). Rosin and Rammler equation has been determined by a new procedure using a software entitled Pixler to delineate images the same as manual method for achieving a proper fragment size distribution by Split-Desktop. The obtained values of n had significant differences with estimated n by the former equations. Relations between n and several blasthole parameters, BI and mean fragment size X 50 of the results and their various combinations have been analyzed. Finally, a new empirical model having a good correlation has been developed to predict n value for using 25 ms electric delay detonators.

中文翻译：

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基于爆破孔参数和可爆性指数预测碎片粒度分布均匀性指数的新模型的开发

均匀性指数n代表碎屑大小分布的范围，用于通过Rosin和Rammler累积分布函数评价碎屑堆的碎屑大小。碎片尺寸分布的均匀性指数 n 已通过数字图像分析技术使用 Split-Desktop 对具有广泛爆炸性指数 (BI) 的五个矿山中的几个爆破孔参数和不同区域的原位岩体条件进行评估。松香和拉姆勒方程已通过新程序确定，使用名为 Pixler 的软件描绘图像，与通过 Split-Desktop 实现适当片段大小分布的手动方法相同。得到的 n 值与由前一个方程估计的 n 值有显着差异。n与几个炮眼参数的关系，已经分析了结果的 BI 和平均片段大小 X 50 及其各种组合。最后，开发了一个具有良好相关性的新经验模型来预测使用 25 ms 电延迟雷管的 n 值。