In the processing of conventional marine seismic data,seawater is often assumed to have a constant velocity model.However,due to static pressure,temperature difference and other factors,random disturbances may often f...In the processing of conventional marine seismic data,seawater is often assumed to have a constant velocity model.However,due to static pressure,temperature difference and other factors,random disturbances may often frequently in seawater bodies.The impact of such disturbances on data processing results is a topic of theoretical research.Since seawater sound velocity is a difficult physical quantity to measure,there is a need for a method that can generate models conforming to seawater characteristics.This article will combine the Munk model and Perlin noise to propose a two-dimensional dynamic seawater sound velocity model generation method,a method that can generate a dynamic,continuous,random seawater sound velocity model with some regularity at large scales.Moreover,the paper discusses the influence of the inhomogeneity characteristics of seawater on wave field propagation and imaging.The results show that the seawater sound velocity model with random disturbance will have a significant influence on the wave field simulation and imaging results.展开更多
花卉植物具有复杂的形态结构和生理特性,传统的欧式几何难以表现其几何造型.为满足花卉建模的高效性和真实感,提出一种基于Perlin噪声的花卉仿真方法.通过Catmull-Rom样条曲线绘制叶片和花瓣的草图轮廓,利用二维Perlin噪声生成草图的深...花卉植物具有复杂的形态结构和生理特性,传统的欧式几何难以表现其几何造型.为满足花卉建模的高效性和真实感,提出一种基于Perlin噪声的花卉仿真方法.通过Catmull-Rom样条曲线绘制叶片和花瓣的草图轮廓,利用二维Perlin噪声生成草图的深度值,用噪声x轴和y轴缩放参数控制叶片和花瓣的卷曲程度,实现了通用、高效的片状器官三维重建.同时,采用Vogel模型构建花卉的形态结构,引入基于双向反射分布函数(bidirectional reflectance distribution function,BRDF)的物理光照渲染真实感.与分形几何、Bézier曲面的对比分析结果表明,该方法在绘制草图时使用控制点少、建模效率高,且花卉模型仿真度高,渲染光照真实感强.展开更多
基金The General Program of National Natural Science Foundation of China under contract No.42074150。
文摘In the processing of conventional marine seismic data,seawater is often assumed to have a constant velocity model.However,due to static pressure,temperature difference and other factors,random disturbances may often frequently in seawater bodies.The impact of such disturbances on data processing results is a topic of theoretical research.Since seawater sound velocity is a difficult physical quantity to measure,there is a need for a method that can generate models conforming to seawater characteristics.This article will combine the Munk model and Perlin noise to propose a two-dimensional dynamic seawater sound velocity model generation method,a method that can generate a dynamic,continuous,random seawater sound velocity model with some regularity at large scales.Moreover,the paper discusses the influence of the inhomogeneity characteristics of seawater on wave field propagation and imaging.The results show that the seawater sound velocity model with random disturbance will have a significant influence on the wave field simulation and imaging results.
文摘花卉植物具有复杂的形态结构和生理特性,传统的欧式几何难以表现其几何造型.为满足花卉建模的高效性和真实感,提出一种基于Perlin噪声的花卉仿真方法.通过Catmull-Rom样条曲线绘制叶片和花瓣的草图轮廓,利用二维Perlin噪声生成草图的深度值,用噪声x轴和y轴缩放参数控制叶片和花瓣的卷曲程度,实现了通用、高效的片状器官三维重建.同时,采用Vogel模型构建花卉的形态结构,引入基于双向反射分布函数(bidirectional reflectance distribution function,BRDF)的物理光照渲染真实感.与分形几何、Bézier曲面的对比分析结果表明,该方法在绘制草图时使用控制点少、建模效率高,且花卉模型仿真度高,渲染光照真实感强.
