自适应步长的海洋流线构造算法  

Adaptive-Step Based Marine Fluid Flow Streamline Constructing Algorithm

作　　者：季民[1] 陈丽[1] 靳奉祥[1,2] 李婷[1] 王春晓[1,3] 孙勇[1] 

机构地区：[1]山东科技大学测绘科学与工程学院,山东青岛266590 [2]山东建筑大学,山东济南250101 [3]海南省测绘地理信息局,海南海口570203

出　　处：《武汉大学学报（信息科学版）》2014年第9期1052-1056,共5页Geomatics and Information Science of Wuhan University

基　　金：高等学校博士学科点专项科研基金资助项目(20113718110001);国家科技支撑计划资助项目(2012BAH27B04;2011BAC03B03);海洋公益性行业科研专项资助项目(2011418017);山东科技大学科研创新团队支持计划资助项目(2011KYTD103);海岛(礁)测绘技术国家测绘地理信息局重点实验室开放研究基金资助项目(2011A04)~~

摘　　要：为深入研究海洋流场的结构特征,在临界点理论的支持下,根据不同的临界点类型提出了充分考虑流场结构特征的初始质点源布置策略,并根据原始网格矩阵中局部网格的流速和流向,提出了一种具有更宽泛步长调整适用度的自适应步长计算模型。该模型可根据具体流场特征实现步长增长倍数和全局步长增长控制的双自由度调整,同时可满足同向加速和逆向减速的步长控制。为实现流线在全局流场中的合理化布置,提出了基于平滑窗口的流线密度调整策略。对全球海洋流场进行可视化实验,结果表明,本文算法在海洋流场结构特征的表达中应用效果较好。The visualization of vector fields has become an important means for the expression of flows in many different disciplines. In order to express a marine fluid flow＇s structure more clearly, based on critical point theory, we present a new seeding point placement strategy and a new adaptive-step com- putation model. Considering a local cell＇s velocity and flow direction jointly with two degrees of free- dom, it adjusts the steps by using two parameters and realizes the step acceleration and deceleration according to the flow direction. For the placement of the global flow field streamlines, we also give a new streamline density adiustment strategy based on a smoothing window. Experimental analysis of a global ocean flow visualization shows that this algorithm better expresses the marine fluid flow struc- ture and suggests a reasonable placement of streamlines.

关 键 词：流场可视化 流线追踪 临界点理论 海洋流场 自适应步长算法 

分 类 号：P229.2[天文地球—大地测量学与测量工程] P208[天文地球—测绘科学与技术]