The possibility of mathematically describing the body surface represents a useful tool for several medical sectors, such as prosthetics or plastic surgery, and could improve diagnosis and objective evaluation of defor...
详细信息
The possibility of mathematically describing the body surface represents a useful tool for several medical sectors, such as prosthetics or plastic surgery, and could improve diagnosis and objective evaluation of deformities and the follow-up of progressive diseases. The approach presented is based on the acquisition of a surface scanned by a laser beam. The 3-D coordinates of the spot generated on the surface by the laser beam are computed by an automatic image analyzer (ELITE system). Using at least two different views of the subject, the 3-D coordinates are obtained by stereophotogrammetry. A software package for graphic representation and extraction of linear superficial and volumetric features from the acquired surface has been developed and some preliminary results with mammary reconstruction are presented. A good mammary reconstruction after mastectomy must achieve two results. First, the reconstruction should follow the patients' wishes and second, the reconstructed breast should be as similar as possible to the contralateral one (symmetry is the most important aesthetic parameter to be considered). To achieve these goals, a knowledge of breast volume, area, and shape features are essential for the surgeon. In such a context, this system could be a valuable tool in improving breast reconstructive surgery. (C) 1998 Society of Photo-Optical Instrumentation Engineers.
An easy conceivable but very powerful method for the visualization of three-dimensional scalar fields is described. The way this method works is illustrated by some examples and the computed pictures are compared with...
详细信息
An easy conceivable but very powerful method for the visualization of three-dimensional scalar fields is described. The way this method works is illustrated by some examples and the computed pictures are compared with the results of other methods of representation.
Modern high-throughput biological research produces enormous amount of data that must be processed by computers, but many biologists dealing with these data are not professional programmers. Despite increased awarenes...
详细信息
Modern high-throughput biological research produces enormous amount of data that must be processed by computers, but many biologists dealing with these data are not professional programmers. Despite increased awareness of interdisciplinary training in bioinformatics, many biologists still find it difficult to create their own computational solutions. VECT, the Visual Extraction and Conversion Tool, has been developed to assist nonprogrammers to create simple bioinformatics. without having to master a programming language. VECT provides a unified graphical user interface for,data extraction, data conversion, output composition, and Perl code generation. Programming using VECT is achieved by visually performing the desired data extraction, conversion, and output composition tasks using some sample user data. These tasks are then compiled by VECT into an executable Perl program, which, can be saved for later use and can carry out the same computation independently of VECT. VECT is released under the GNU General Public License and isfreely availablefor all major computing platforms including Macintosh (R) OSX, Linux, and Microsoft (R) Windows (R) at www. complex. iastate. edu.
Most current methods for character skinning can be categorized into 1) geometric techniques, which are fast and easy to use but often lack physical realism, 2) data-driven approaches, which require a large set of exam...
详细信息
Most current methods for character skinning can be categorized into 1) geometric techniques, which are fast and easy to use but often lack physical realism, 2) data-driven approaches, which require a large set of examples that are tedious to edit, and 3) physics-based methods, which are highly realistic but slow and difficult to use. Recently introduced geometric Implicit Skinning methods can solve contact interactions and skin elasticity with results comparable to physics-based simulation in real-time. In this paper we introduce an animation method that adds anatomical plausibility while benefiting from the advantages of Implicit Skinning. We propose an efficient way to model muscle primitives with implicit surfaces. Volumetric extrusions of individual muscles are attached to muscle center lines simulated with a fast, low-dimensional physics-based approach (Position Based Dynamics of one-dimensional line segments). This combination of physics-based simulation with implicit modeling allows us to elegantly resolve muscle-muscle and muscle-bone collisions and add dynamic effects such as flesh jiggling while guaranteeing volume preservation (which is a property of real biological muscles) and producing visually plausible skin-skin contact behavior. Our method runs at interactive frame-rates and features intuitive modeling parameters which allow animators to quickly explore a variety of designs and physics-based effects. (C) 2018 Elsevier Ltd. All rights reserved.
Information visualization has been defined as the use of computer-supported, interactive, visual representations of abstract data to amplify cognition. Many intriguing visualizations help deal with the data overload p...
详细信息
Information visualization has been defined as the use of computer-supported, interactive, visual representations of abstract data to amplify cognition. Many intriguing visualizations help deal with the data overload problem. Examples include visual tools based on similarity, relevance, explicit entity relationships, patterns in citations, and patterns in metadata. The literature describing creative visual approaches and prototype implementations is large and growing. However, little has been published on usage experiences with such tools. The In-Spire visualization tool based on the previous Spire system uses statistical word patterns to characterize documents based on their text content. Among its tools are two visualizations that show document themes, similarities, and differences: document-centric Galaxy uses a dot plot metaphor, and collection-centric ThemeView uses a landscape metaphor. People targeted several additional In-Spire analytic features explicitly at the user community. Their goal in developing In-Spire was to provide a data visualization tool that let users deal with many documents, reducing the amount of time spent crafting queries and the chance of eliminating useful material before the user can see it. It also needed capabilities that let users understand a collection of material at an overview level first, instead of launching immediately into reading individual documents. The tool needed to support analytic demands for both convergent focusing on a particular set of information, relationships, or thesis in depth and divergent seeking alternative explanations and remaining open to other potentially interesting information or relationships understanding methods.
The design of a graphical-display system with advanced facilities for assisting the user and minimising computational equirements is described. Pictures of good quality are produced. They require a minimum of store ac...
详细信息
The design of a graphical-display system with advanced facilities for assisting the user and minimising computational equirements is described. Pictures of good quality are produced. They require a minimum of store accesses to draw, and can be constructed and modified easily. Facilities include the association of light-pen ‘hits’ with display-file and data-base information, the ability to nest subpictures to any level, a special symbol generator, and the ability to modify certain picture parameters. The hardware is modular in construction and makes use of a novel type of ‘ring’ highway. It is shown that this is particularly suitable in the graphical-display environment.
The experimental tutorial software described in this paper is designed specifically for engineering education at the university level, and it is significantly different in purpose and structure from other educational ...
详细信息
The experimental tutorial software described in this paper is designed specifically for engineering education at the university level, and it is significantly different in purpose and structure from other educational software, Its goal is to help students understand, visualize, and connect basic concepts, It is not a design tool or a wealth of hyperlinked text or an infinite source of drill problems, It is intended to be a dynamic and flexible resource for instructors as well as students and to be used by groups as well as individuals. It takes advantage of currently available high-resolution graphics capability to go beyond what can reasonably be expected of textbooks or computer systems with small low-resolution displays. Since the software is written as an X Windows Motif application, it achieves a wide degree of platform independence for workstations and PC's, In addition, the tutorial set can be distributed without license fees or additional software acquisition costs for the user.
Structural biology needs sensitive tools to detect homology between proteins of low sequence identity, but with closely related 3-D structures. Using a conventional dotplot method, we therefore introduced 2 concepts t...
详细信息
Structural biology needs sensitive tools to detect homology between proteins of low sequence identity, but with closely related 3-D structures. Using a conventional dotplot method, we therefore introduced 2 concepts to improve the search for similarities between secondary structures of analyzed proteins: 'hydrophobic neighboring homology' (HNH) and 'amino acid degeneracy classes'. The amino acids are grouped into 3 subsets: hydrophobic, hydrophilic and mimetic, A 'Neighboring Similarity Index' (NSI) is calculated for every residue pair and quantifies its neighbor homology. By thresholding the homology matrix and filtering the dotplot, the homologous patterns are extracted. We have evaluated the efficiency and limits of the method using 21 protein pairs extracted from the Protein Data Bank (PDB), or selected from the recent literature. Globally, we again find the homologous structures (alpha-helices and beta-strands) of these pair proteins, The introduction of neighbor residue hydrophobicity in the conventional dotplot improves the alignment of proteins with low sequence identity (< 25%). HNH, written in standard ANSI C with the graphic library X11, under UNIX, is available on request.
A ''package''-module of commented source code-for the computer program Mathematica has been designed to reconstruct surfaces from curves, collected in parallel serial sections through these surfaces. T...
详细信息
A ''package''-module of commented source code-for the computer program Mathematica has been designed to reconstruct surfaces from curves, collected in parallel serial sections through these surfaces. The package contains routines to interpolate digitized curves using continuous functions, to interpolate transversally between the resulting continuous curves, and to render the results of this later operation as a parametrized surface in three dimensions. This paper provides a listing of the package and an example of surface reconstruction using curves which were collected from serial thin sections through a garnet porphyroblast with spiral-shaped inclusion trails.
A description is given of MML, a special-purpose programming language developed for procedural models. The language is used to specify both the generation of the model and the motion of the objects in the model. A mot...
详细信息
A description is given of MML, a special-purpose programming language developed for procedural models. The language is used to specify both the generation of the model and the motion of the objects in the model. A motion specification technique that works well with natural phenomena is presented. It has the advantages of being independent of the detailed structure of the object and lending itself to the construction of good user interfaces for animation systems. The MML language can be used to produce both interactive and batch animation programs. The user interface for the interactive animation programs is automatically constructed by the MML system. Several examples of the use of MML are given.
暂无评论