Robert Marschallinger

A voxel visualization and analysis system based on AutoCAD

Abstract A collection of AutoLISP programs is presented which enable the visualization and analysis of voxel models by AutoCAD rel. 12/rel. 13. The programs serve as an interactive, graphical front end for manipulating the results of three-dimensional modeling software producing block estimation data. ASCII data files describing geometry and attributes per estimation block are imported and stored as a voxel array. Each voxel may contain multiple attributes, therefore different parameters may be incorporated in one voxel array. Voxel classification is implemented on a layer basis providing flexible treatment of voxel classes such as recoloring, peeling, or volumetry. A versatile clipping tool enables slicing voxel arrays according to combinations of three perpendicular clipping planes. The programs feature an up-to-date, graphical user interface for user-friendly operation by non AutoCAD specialists.

Solid modeling of fossil small mammal teeth

This paper presents an approach to create solid models of fossil small mammal teeth using a combination of microcomputed tomography, object based image analysis and voxel modeling. Small mammal teeth, because of their durability, are widely found in Cenozioc sediments the world over and play a key role in stratigraphy as well as in researching the rapid evolution and the paleogeographic spreading of small mammals. Recent advances in microcomputed tomography make this non-destructive analysis method an ideal data source for high-resolution 3D models of fossil small animal teeth. To derive internally consistent solid models of such fossils from micro-CT imagery, we propose a combination of 3D object based image analysis and solid modeling. Incorporating paleontological expert knowledge in the image processing cycle, object based image analysis yields topologically consistent image stacks classified by the main tooth components—enamel, dentine and pulp. Forwarding these data to a voxel modeling system, they can be quantitatively analyzed in an unprecedented manner: going beyond the possibilities of the state-of-art surface models, solid models are capable of unambiguously portraying the entire object volume—teeth can be peeled by material properties, subvolumes can be extracted and automatically analyzed by Boolean operations. The proposed method, which can be flexibly extended to handle a range of paleontological and geological micro-objects, is demonstrated with two typical fossil small mammal teeth.

A visual LISP program for voxelizing AutoCAD solid models

AutoCAD solid models are increasingly recognized in geological and geotechnical 3D modeling. In order to bridge the currently existing gap between AutoCAD solid models and the grid modeling realm, a Visual LISP program is presented that converts AutoCAD solid models into voxel arrays. Acad2Vox voxelizer works on a 3d-model that is made up of arbitrary non-overlapping 3D-solids. After definition of the target voxel array geometry, 3D-solids are scanned at grid positions and properties are streamed to an ASCII output file. Acad2Vox has a novel voxelization strategy that combines a hierarchical reduction of sampling dimensionality with an innovative use of AutoCAD-specific methods for a fast and memory-saving operation. Acad2Vox provides georeferenced, voxelized analogs of 3D design data that can act as regions-of-interest in later geostatistical modeling and simulation. The Supplement includes sample geological solid models with instructions for practical work with Acad2Vox. Display Omitted Acad2Vox converts arbitrary AutoCAD 3D-solids to 3D grid data.It follows a novel, CAD-oriented and efficient voxelization strategy.Multiple AutoCAD versions are supported.

Geographic Information Science as a common cause for interdisciplinary research

Geographic Information Science (GIScience) seeks to understand the nature of geographic phenomena and geo-spatial information. It provides theoretical foundations for Geographic Information Systems (GIS) and the rationale for research and development in GIS and their applications. In this article, we analyse the role of GIScience as a common denominator among and between various disciplines, acting as a facilitator for interdisciplinary research. Starting from the development of a coordinated and structured doctoral programme,ten senior university faculty members from different disciplines examine the commonalities of spatial (Because of limited space we focus in this paper on the spatial domain and will only briefly reflect the spatio-temporal complexity) concepts in their respective fields in three interdisciplinary research clusters. Since the educational rationale was published recently, we focus on the role of GIScience in building an interdisciplinary and inter-departmental research alliance and conclude that the university-wide visibility has increased and opens new changes for another ‘spatial turn’.

Usability and Potential of Geostatistics for Spatial Discrimination of Multiple Sclerosis Lesion Patterns

In multiple sclerosis (MS) the individual disease courses are very heterogeneous among patients and biomarkers for setting the diagnosis and the estimation of the prognosis for individual patients would be very helpful. For this purpose, we are developing a multidisciplinary method and workflow for the quantitative, spatial, and spatiotemporal analysis and characterization of MS lesion patterns from MRI with geostatistics.

A MS‐lesion pattern discrimination plot based on geostatistics

A geostatistical approach to characterize MS‐lesion patterns based on their geometrical properties is presented.