Application Of Ladar In The Analysis Of Aggregate Characteristics

Application of LADAR in the Analysis of Aggregate Characteristics

"NCHRP Project 4-34, 'Application of LADAR in the Analysis of Aggregate Characteristics,' was conducted by Virginia Polytechnic Institute and State University, Blacksburg, Virginia, with participation by the University of Illinois at Urbana-Champaign. The objective of the project was to develop and evaluate a laser detection and ranging (LADAR) system capable of precise and accurate measurement of the aggregate characteristics of shape, volume, angularity, surface texture, specific surface area, and volumetric gradation. Ideally, the final system would be applicable to aggregate in three size categories--coarse (2 in. to #4), fine (#4 to #200), and microfine (P200)--and suitable for routine use in research, central, and field laboratories for Portland cement concrete and asphalt concrete mixture design and quality assurance. The project, which developed new equipment and computer algorithms, proved technically challenging. The project team developed a prototype Fourier transform interferometry (FTI) system with fully functional hardware and software. The system can characterize aggregate shape, angularity, texture, surface area, and volume of a wide range of aggregate sizes with high accuracy. Assembly and operation of the FTI system consisting of a chargecoupled device (CD) camera, a fringe source, a sample platform, and a software package are fully documented in the report. The accuracy and precision of the prototype FTI system are comparable to or better than those of other systems now available to automatically measure aggregate characteristics, but its current range of aggregate size--3/4 in. to #50--is narrower than desired. Extending this size range is possible in the future by using a CCD camera with a larger field of view and increasing the system resolution through appropriate selection of the equipment components."

Summary of Progress - National Cooperative Highway Research Program

Modeling, Analysis, and Visualization of Anisotropy

This book focuses on the modeling, processing and visualization of anisotropy, irrespective of the context in which it emerges, using state-of-the-art mathematical tools. As such, it differs substantially from conventional reference works, which are centered on a particular application. It covers the following topics: (i) the geometric structure of tensors, (ii) statistical methods for tensor field processing, (iii) challenges in mapping neural connectivity and structural mechanics, (iv) processing of uncertainty, and (v) visualizing higher-order representations. In addition to original research contributions, it provides insightful reviews. This multidisciplinary book is the sixth in a series that aims to foster scientific exchange between communities employing tensors and other higher-order representations of directionally dependent data. A significant number of the chapters were co-authored by the participants of the workshop titled Multidisciplinary Approaches to Multivalued Data: Modeling, Visualization, Analysis, which was held in Dagstuhl, Germany in April 2016. It offers a valuable resource for those working in the field of multi-directional data, vital inspirations for the development of new models, and essential analysis and visualization techniques, thus furthering the state-of-the-art in studies involving anisotropy.