A five dimensional (5D) geospatial dataset consists of several multivariable 4D datasets, which are sequences of time-varying volumetric 3D geographical datasets. These datasets are typically very large in size and de...
详细信息
A five dimensional (5D) geospatial dataset consists of several multivariable 4D datasets, which are sequences of time-varying volumetric 3D geographical datasets. These datasets are typically very large in size and demand a great amount of resources for storage and transmission. In this paper, we present a lossy compression technique for 5D geospatial data as a whole, instead of applying 3D compression method on each 3D slice of the 5D dataset. Our lossy compression technique efficiently exploits spatial and temporal similarities between 2D data slices and 3D volumes in 4D oceanographic datasets. 5D-ODETLAP, which is an extension of, but essentially different from, the Laplacian partial differential equation, solves a sparse overdetermined system of equations to compute data at each point in (x,y,z,t,v) space from the data given at a representative set of points. 5D-ODETLAP is not restricted to certain types of datasets. For different datasets, it has the flexibility to approximate each one according to their respective data distributions by using suitable parameters. The final approximation is further compressed using Run Length Encoding. We use different datasets and metrics to test 5D-ODETLAP, and performance evaluations have shown that the proposed compression technique outperforms current 3D-SPIHT method on our selected datasets, from the World Ocean Atlas 2005. Having about the same mean percentage error, 5D-ODETLAP's compression result produces much smaller maximum error than 3D-SPIHT. A user-defined mean or maximum error can be set to obtain desired compression in the proposed method, while not in 3D-SPIHT.
The objective of this paper is to explain the machinery of the Chaos Game used in the context of various types of iterated function system specifications. Although the discussion is kept in the framework of a mathemat...
详细信息
In this paper we present a distributed scene graph architecture for use in the blue-c, a novel collaborative immersive virtual environment. We extend the widely used OpenGL Performer toolkit to provide a distributed s...
详细信息
The analysis and treatment of cerebral aneurysms are important in neuroradiology. To support physicians in these tasks a desktop application for the visual analysis of aneurysm data called Aneulysis was developed. Bec...
详细信息
We present an approach for computing camera animations composed of optimal views to support the visual exploration of blood flow data using cerebral aneurysms as major example. Medical researchers are interested in he...
详细信息
Several experiments have provided evidence that ego-centric distances are perceived as compressed in immersive virtual environments relative to the real world. The principal factors responsible for this phenomenon hav...
详细信息
Research and development activities are facing a continuing globalization. Networks are getting more important than companies or institutes. Main reasons for this trend are: (Faster) access to new knowledge and techno...
详细信息
In the ATC domain, simulated training is an effective approach to cultivate controllers, and ATC simulators providing vivid simulated environment for the trainees are the key devices with high complexity. In this pape...
详细信息
In augmented reality, it is often necessary to draw the user's attention to particular objects in the real world without distracting her from her task. We explore the effectiveness of directing a user's attent...
详细信息
ISBN:
(纸本)9781450302289
In augmented reality, it is often necessary to draw the user's attention to particular objects in the real world without distracting her from her task. We explore the effectiveness of directing a user's attention by imperceptibly modifying existing features of a video. We present three user studies of the effects of applying a saliency modulation technique to video;evaluating modulation awareness, attention, and memory. Our results validate the saliency modulation technique as an alternative means to convey information to the user, suggesting attention shifts and influencing recall of selected regions without perceptible changes to visual input. Copyright 2011 ACM.
Quick extraction of the extremum eigenpairs of a real symmetric matrix is very important in engineering. Using neural networks to complete this operation is in a parallel manner and can achieve high performance. So, t...
详细信息
暂无评论