A Nonparametric Procedure for Comparing Methods to Estimate Particle Size Distribution

• Activity Number: 416
• Type: Contributed
• Date/Time: Tuesday, August 5, 2014 : 2:00 PM to 3:50 PM
• Sponsor: Section on Physical and Engineering Sciences
• Author(s): Scott Richter*+ and Melinda McCann
• Companies: University of North Carolina at Greensboro and Oklahoma State University
• Keywords: nonparametric ; permutation test ; particle size distribution

Abstract

In industrial applications, measuring particle size distributions is critical for predicting the performance of cement-based materials. There are many methods available for these situations. Two of these methods include acoustic attenuation spectroscopy (acoustic) and automated scanning electron microscopy (ASEM). For each method a sample of the material whose particle size distribution we wish to estimate is measured with an appropriate instrument and an estimated distribution is obtained. The acoustic method measures the attenuation and sound speed caused due to change in intensity and phase of the sound wave at variable gaps and frequencies. Consequently the same experimental material is utilized for several different measurements which are combined to obtain an estimated distribution. Note that these measurements are not independent. Also, different samples of the experimental material result in different (albeit sometimes only slightly) estimated distributions. Alternatively ASEM utilizes a scanning electron microscope to find, measure, and count the number of particles when the sample of experimental material is dispersed onto carbon tape. These measurements also res