The Size And Shape Property Study Of Aggregate Particles Based On The Second Moment Method

The determination and measurement of the particles size is carried out in many fields of study.There are certain relationship between the shape and size.In the fields of geology,metallurgy,agriculture,medicine and aggregates engineering,the range of size particles is infinitely large,therefore,the size determination is more complex.In this paper,the particle size measurement method is used to obtain the aggregate grain bounding box with rotational invariance,which is compared with the particle size obtained by the caliper measurement method.The geometrical irregularity of aggregates is very complex.At the same time,characterizing the shape parameters of aggregate particles method is given.In order to characterize the relationship between the geometrical irregularities of aggregate particles and finding out the most effective characteristic parameters of the estimated shape,a set of indexes for quantifying aggregate shape,aspect ratio,angularity and surface texture are proposed.The relationship between the particle shape parameters and the particle size was analyzed by SPSS data mining software,including the analysis of a large number of aggregated data,the simple clustering of the extracted data features,the relative error of the particle size,the relationship between particle size and shape is established.The correlation coefficient between particle size and shape is analyzed,and the correlation coefficient between variables is obtained.The shape parameter factors affecting the relative error of particle size are analyzed.In this paper,the NI VisionAssistant with LabVIEW software prepares the aggregate particle image collected by the camera.The particle analysis function in the software gives the area and perimeter of the particles,the area of ? ? the convex hull and the circumference of the convex hull characteristic parameters.The direction of the particle bounding box means that the least-second moment algorithm is realized by Matlab software programming.After reading the image,we run this program to show the direction of the particle label image,enclosing the rectangular box and obtain the characteristic parameter data table to show the particle center of abscissa,ordinate,the long axis of the particle,short axis(pixel value),and direction(the angle of degrees between the long axis of the rectangular frame and the horizontal axis in the clockwise direction).In this paper,the geometrical irregularities parameters of aggregate particles are determined,which is aspect ratio,angularity and roughness.By the way,the quantitative shape parameters are determined.The correlation between the particle size and the three shape parameters is analyzed,the Pearsoncorrelation coefficient and the partial correlation coefficient are obtained.The shape parameters affect the particle sizes.For the aggregate error of the larger particle size,including the angular error and the aspect ratio of the shape parameter,which in the second moment method of the particle size measurement,the aspect ratio of the parameter is calculated,at the same time,the error is accuracy and feasibility.