33127711
Real-Time Visualization of Tire Tracks in Dynamic Terrain with LOD
In off-road simulation, the terrain is being modified as a result of its interaction with the vehicles. Previous methods dealing with tire tracks are to animate tire tracks and have no interactivity. In this paper, we describe a method to render tire tracks in dynamic terrain. In the base of hierarchical structure for terrain LOD, hierarchical structure starts at a resolution sufficient to represent the initial terrain, and then increases the resolution wherever necessary at the modified terrain regions. To avoid the cracks at the boundary between terrain cells, which are modified and increased the resolution, an algorithm based on window-scanning avoids cracks between neighboring cells in the 2×2 window is given. This algorithm avoids the transfer of cracks effectively through guaranteeing the results after window scanning will not impact the edges processed previously. The results of experiments show that not only this algorithm avoids crack effectively, but also the cost of computing is very low.
34224506
Exploiting Frame-to-Frame Coherence for Rendering Terrain Using Continuous LOD
It is the key issue of the terrain real-time rendering to reduce the time-spending for the level-of-detail. The concept of triangle live frame is introduced in this paper. Using this live frame, the algorithm reuses per-vertex visibility computation from previously displayed frames efficiently during continuous view-dependent level-of-detail visualizations. This algorithm decreases to a certain extent computing the distance from the viewpoint to vertex at each frame. Experimental results show that the algorithm reduces the time effectively to produce the LOD terrain.
17024668
Design and analysis of bi-directional pumping silicon Raman laser
In this paper, a novel design of bi-directional pumping scheme is proposed and analyzed for the first time in an attempt to verify its validity as a mean for loss reduction and gain enhancement in Raman silicon laser. FCA loss is identified as the key loss contributor in silicon Raman process which is highly dependent on peak input pump power level, from the simulation results to account for various loss mechanisms in on-off gain simulation. To solve the problem of high threshold and low gain obtained in Raman silicon laser, bi-directional pumping scheme is proposed to have the effects of loss reduction by peak power limitation and Raman gain enhancement through average power increment. This is also substantiated by simulation of average and instantaneous pump power level along the silicon waveguide length. With bi-directional pumping, Raman silicon laser could improve in its threshold power and gain/slope efficiency to enable it better application credibility.
17362173
A New Heuristic Reduct Algorithm Base on Rough Sets Theory
Real world data sets usually have many features, which increases the complexity of data mining task. Feature selection, as a preprocessing step to the data mining, has been shown very effective in reducing dimensionality, removing irrelevant data, increasing learning accuracy, and improving comprehensibility. To find the optimal feature subsets is the aim of feature selection. Rough sets theory provides a mathematical approach to find optimal feature subset, but this approach is time consuming. In this paper, we propose a novel heuristic algorithm based on rough sets theory to find out the feature subset. This algorithm employs appearing frequency of attribute as heuristic information. Experiment results show in most times our algorithm can find out optimal feature subset quickly and efficiently.
14759570
Simplifying the Reconstruction of 3D Models using Parameter Elimination
Reconstructing large models from images is a significant challenge for computer vision, computer graphics, and related fields. In this paper, we present an approach for simplifying the reconstruction process by mathematically eliminating external camera parameters. This results in less parameters to estimate and in an overall significantly more robust and accurate reconstruction. We reformulate the problem in such a manner as to be able to identify invariants, eliminate superfluous parameters, and measure the performance of our formulation under various conditions. We compare a two-step camera orientation-free method, where the majority of the points are reconstructed using a linear equation set, and a camera position-and- orientation free method, using a degree-two equation set. Both approaches use a full perspective camera and are applied to synthetic and real-world datasets.
7669221
Function Finding and Constants Creation Method in Evolutionary Algorithm Based on Overlapped Gene Expression
Evolutionary algorithm based on overlapped gene expression (EAOGE) is a new technology of evolutionary algorithm which is inspired by the overlap gene expression in biological research. Different from existing works, EAOGE suggests a new expression structure of genes, and these genes have a probability to overlapped express in some segments. It uses chromosomes of fixed length to represent expression trees of different shapes and sizes. It does unconstrained search in the genome space and still ensures validity of the expression. This paper implements EAOGE algorithm and proposes a new constants creation method. Extensive experiments show that the method significantly improves the precision in the problems of function finding, and the precision of the new method is about 12.8 times to traditional algorithm at least.
3794965
A unified framework for name disambiguation
Name ambiguity problem has been a challenging issue for a long history. In this paper, we intend to make a thorough investigation of the whole problem. Specifically, we formalize the name disambiguation problem in a unified framework. The framework can incorporate both attribute and relationship into a probabilistic model. We explore a dynamic approach for automatically estimating the person number K and employ an adaptive distance measure to estimate the distance between objects. Experimental results show that our proposed framework can significantly outperform the baseline method.