To make progress in understanding knot theory, we will need to interact with the projected representations of mathematical knots which are of course continuous in 3d but significantly interrupted in the projective ima...
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ISBN:
(纸本)9780819484055
To make progress in understanding knot theory, we will need to interact with the projected representations of mathematical knots which are of course continuous in 3d but significantly interrupted in the projective images. One way to achieve such a goal would be to design an interactive system that allows us to sketch 2d knot diagrams by taking advantage of a collision-sensing controller and explore their underlying smooth structures through a continuous motion. Recent advances of interaction techniques have been made that allow progress to be made in this direction. Pseudo-haptics that simulates haptic effects using pure visual feedback can be used to develop such an interactive system. This paper outlines one such pseudo-haptic knot diagram interface. Our interface derives from the familiar pencil-and-paper process of drawing 2d knot diagrams and provides haptic-like sensations to facilitate the creation and exploration of knot diagrams. A centerpiece of the interaction model simulates a "physically" reactive mouse cursor, which is exploited to resolve the apparent conflict between the continuous structure of the actual smooth knot and the visual discontinuities in the knot diagram representation. Another value in exploiting pseudo-haptics is that an acceleration (or deceleration) of the mouse cursor (or surface locator) can be used to indicate the slope of the curve (or surface) of whom the projective image is being explored. By exploiting these additional visual cues, we proceed to a full-featured extension to a pseudo-haptic 4d visualization system that simulates the continuous navigation on 4d objects and allows us to sense the bumps and holes in the fourth dimension. Preliminary tests of the software show that main features of the interface overcome some expected perceptual limitations in our interaction with 2d knot diagrams of 3d knots and 3d projective images of 4d mathematical objects.
We present an initial attempt for the development of a distributed and scalable GIS-like tool for the storage, selection andvisualization of 4d marine datasets. The aim of this tool is to standardize the variety of d...
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We present an initial attempt for the development of a distributed and scalable GIS-like tool for the storage, selection andvisualization of 4d marine datasets. The aim of this tool is to standardize the variety of data available for the water column and support non-technical marine biologists in manipulating 4d marine datasets. The tool is developed towards answering specific environmental and biological questions regarding ocean processes and essential fish habitat mapping in three dimensions.
It is becoming increasingly common to image time-resolved flow patterns through the vascular system in all three spatial dimensions using non-invasive methods. The capability to generate four-dimensional (4d) (x, y, z...
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ISBN:
(纸本)0819452807
It is becoming increasingly common to image time-resolved flow patterns through the vascular system in all three spatial dimensions using non-invasive methods. The capability to generate four-dimensional (4d) (x, y, z and time) vascular flow data is growing in several modalities. Vastly undersampled Isotropic PRojection (VIPR) is one such method using high-resolution, fast Magnetic Resonance Imaging (MRI) of the vasculature system during intravenous contrast injection. VIPR currently produces 4ddata sets of twenty to forty frames of 256(3) voxels each, and stronger magnets will allow higher resolution time series that generate gigabytes of data. Real-time visualization and analysis of 4ddata can quickly overwhelm the memory and processing capabilities of desktop workstations. 4d Cluster visualization (4dCV) offers a straightforward, scalable approach to interactively display and manipulate 4d, reconstructed, VIPR data sets. 4dCV exploits the inherently parallel nature of 4d frame data to interactively manipulate and render individual 3ddata frames simultaneously across all nodes of a visualization cluster. An interactive animation is produced in real-time by reading back the 2d rendered results, to a central animation console where the image sequence is assembled into a continuous stream for display. Basic 4dCV can be extended to allow rendering of multiple frames on one node, compression of image streams for serving remote clinical workstations, and local archival storage of 3ddata frames at the cluster nodes for quick retrieval of medical exams. 4d Cluster visualization concepts can also be extended to distributed and Grid implementations.
A person with an asymmetric morphology of maxillofacial skeleton reportedly possesses an asymmetric jaw function and the risk to express temporomandibular disorder is high. A comprehensive analysis from the point of v...
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ISBN:
(纸本)0819455563
A person with an asymmetric morphology of maxillofacial skeleton reportedly possesses an asymmetric jaw function and the risk to express temporomandibular disorder is high. A comprehensive analysis from the point of view of both the morphology and the function such as maxillofacial or temporomandibular joint morphology, dental occlusion, and features of mandibular movement pathways is essential. In this study, the 4d jaw movement visualization system was developed to visually understand the characteristic jaw movement, 3d maxillofacial skeleton structure, and the alignment of the upper and lower teeth of a patient. For this purpose, the 3d reconstructed images of the cranial and mandibular bones, obtained by computed tomography, were measured using a non-contact 3d measuring device. and the obtained morphological images of teeth model were integrated and activated on the 6 dOF jaw movement data. This system was experimentally applied and visualized in a jaw deformity patient and its usability as a clinical diagnostic support system was verified.
during the last decade, extensive research efforts have been made on the development of four-dimensional (4d) models (space + time) which integrate computer graphics of three-dimensional geometrical models to scheduli...
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during the last decade, extensive research efforts have been made on the development of four-dimensional (4d) models (space + time) which integrate computer graphics of three-dimensional geometrical models to scheduling data with a view to generating graphic visualization of construction processes for planning anddecision making purposes. Nevertheless, these 4d applications to construction planning are often limited to the component level of a building. Their major drawback is the lack of pragmatic site management features, such as analysis of resource requirements for individual construction activity, generation of site facility layouts, quantification of construction materials and cost evaluation over a specified time period. The objective of this study on 4d graphics for construction planning and site utilization (acronym 4d-GCPSU) is mainly to furnish a solution to the aforementioned problem. In this paper, our works on 4d model in a broader site management context aiming to assist planners to deal with day to day activities are delineated. The prospective requirements for 4d application to support practical use on site management are also highlighted. (C) 2003 Elsevier Science Ltd. All rights reserved.
Conventional methods to diagnose and follow treatment of Multiple Sclerosis require radiologists and technicians to compare current images with older images of a particular patient, on a slice-by-slice basis. Although...
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ISBN:
(纸本)0819440051
Conventional methods to diagnose and follow treatment of Multiple Sclerosis require radiologists and technicians to compare current images with older images of a particular patient, on a slice-by-slice basis. Although there has been progress in creating 3ddisplays of medical images, little attempt has been made to design visual tools that emphasize change over time. We implemented several ideas that attempt to address this deficiency. In one approach, isosurfaces of segmented lesions at each time step were displayed either on the same image (each time step in a different color), or consecutively in an animation. In a second approach, voxel-wise differences between time steps were calculated anddisplayed statically using ray casting. Animation was used to show cumulative changes over time. Finally, in a method borrowed from computational fluiddynamics (CFd), glyphs (small arrow-like objects) were rendered with a surface model of the lesions to indicate changes at localized points.
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