视频对象分割及跟踪方法研究

讨论和分析了视频对象全自动提取及后续帧中的跟踪过程及采用的方法 ,对其算法、分割性能和结果进行了比较和评述。并结合Hausdorff和Snake跟踪器 ,对初始对象轮廓进行跟踪。结果证明 ,这种跟踪方法能有效地解决对象被遮挡和形变以及背景移动的问题     

运用GVF Snake算法提取水域的不规则边界

GVF Snake是一种改进型主动轮廓提取算法。本文在详细介绍GVF Snake原理的基础上,重点对GVF Snake的内、外部约束力在边界提取中的作用以及初始边界对提取结果的影响进行了实验研究,提出了初始边界和内部约束力权值的合理设置方法,设计并实现了交互式GVF Snake算法,并用于提取遥感影像上水域的不规则边界。该算法采用种子点区域生长法自动给出水域的初始边界,采用人机交互法设置内部约束力权值,然后运用GVF Snake算法搜索水域的实际边界。实验表明：对于形状极不规则的水域,交互式GVF Snake算法也能方便、快速、准确地获取其边界。     

膨胀系数可调的Balloon Snake方法在道路轮廓提取中的应用

以条带检测的结果初始化道路轮廓,利用balloon snake方法提取道路轮廓.在初始道路轮廓存在缺失的情况下,balloon snake的膨胀作用可以找回丢失的道路片段,提高道路提取的完整性.基于图像梯度和轮廓曲率调节膨胀系数,降低道路提取效果对膨胀系数的敏感,并加快道路轮廓的扩张,减少迭代次数.通过多幅道路图像的试...     

蛇类人工养殖与气象条件关系的初步研究

根据蛇场养殖经验和实验 ,得到人工养蛇的不同生育阶段的温、湿度指标 ,为进一步提高养蛇的经济效益 ,提供一些技术参数     

Application of Active Contour Model in Tracking Sequential Nearshore Waves

In the present study,a generalized active contour model of gradient vector flow is combined with the video techniques of Argus system to delineate and track sequential nearshore wave crest profdes in the shoaling process,up to their breaking on the shorehne.Previous applications of active contour models to water wave problems are limited to controllable wave tank experiments.By contrast,our application in this study is in a nearshore field environment where oblique images obtained under natural and varying condition of ambient light are employed.Existing Argus techniques produce plane image data or time series data from a selected small subset of discrete pixels.By contrast,the active contour model produces line image data along continuous visible curves such as wave crest profdes.The combination of these two existing techniques,the active contour model and Argus methodologies,facilitates the estimates of the direction wave field and phase speeds within the whole area covered by camera.These estimates are useful for the purpose of inverse calculation of the water depth.Applications of the present techniques to Hsi-tzu bay where a beach restoration program is currently undertaken are illustrated.This extension of Argus video techniques provides new application of optical remote sensing to study the hydrodynamics and morphology of a nearshore environment.     

An automated image-based technique for tracking sequential surface wave profiles

Fast-deforming steep surface wave profiles are of particular interests to the design of marine structures and validation of numerical models. In this paper, an improved active contour model, gradient vector flow (GVF) snake, is adapted to automatically track sequential wave profiles taken by a non-intrusive high-speed imager. The robustness and efficiency of the adapted GVF snake is demonstrated through accurately delineating temporal and spatial wave profiles of three examples, including a spiller, a plunger, and a plunging breaker striking a vertical cylinder. Detailed characterizations to these breaking surface wave profiles are given. Overall, the automated adapted GVF snake imaged-based technique is shown to be a power tool for measuring surface wave motions and interfacial flows.     

正射影像镶嵌线自动搜索的视差图算法

提出了一种基于正射影像视差图的区域级镶嵌线搜索算法。首先利用半全局约束立体匹配算法(semi-global matching,SGM)分别计算立体像对的左右视差图,并通过自适应阈值化去除细小的噪声区域,再经数学形态学方法进一步削弱噪声影响和填补小的漏洞区域,得到了较为精细的房屋等非地面区域的分割结果,从而分离出地面与非地面区域;然后采用改进的贪婪蛇搜索算法进行镶嵌线搜索,以提高算法的稳健性。试验表明,本文算法能很好地避开房屋等明显突出地表的实体,得到不穿越非地面区域的最优路径。     

海蛇乙醇浸出物对小鼠学习记忆的影响

本研究采用学习记忆行为训练和生化测定的方法,观察了我国４种常见海蛇的乙醇浸出物（ＡｌｃｏｈｏｌｉｃＥｘｔｒａｃｔｓｏｆＢｏｄｉｅｓｏｆＳｅａ　Ｓｎａｋｅ．ＡＥＢＳＳ）对小鼠的正常学习记忆、东莨菪碱（Ｓｃｏｐｏｌａｍｉｎｅ,Ｓｃｏｐ）所致记忆障碍、脑不同部位蛋白质含量的影响。结果表明,ＡＥＢＳＳ（剂量５００ｍｇ浸出蛋白／ｋｇ体重以上）对正常小鼠的学习记忆能力及脑内蛋白质合成有明显的促进作用;ＡＥＢＳＳ还能极显著地改善Ｓｃｏｐ所致的学习记忆障碍,使Ｓｃｏｐ组大脑皮层和小脑的蛋白质含量显著增加,海马脑区的蛋白质含量增加极显著。结果提示,ＡＥＢＳＳ对小鼠学习记忆的作用机制可能与中枢胆碱能递质系统的蛋白质合成有关。     

First record of sea snake (Hydrophis elegans, Hydrophiinae) entrapped in marine debris

Entanglement in derelict fishing gear and other marine debris is a major threat to the survival of large marine wildlife like cetaceans, seabirds and sea turtles. However, no previous reports of entanglement or entrapment have been recorded in sea snakes (Hydrophiinae). We report here on a sea snake (Hydrophis elegans) found with a ceramic washer encircling its body captured from the north-east coast of Queensland, Australia. The ring had constricted the body and over time caused extensive damage to the underlying tissues. A post-mortem examination showed the snake was severely emaciated as the ring restricted the passage of food to the stomach and intestine. This is the first record of mortality due to marine debris entrapment in sea snakes.     

DSM辅助下城区大比例尺正射影像镶嵌线智能检测

传统算法以重叠区域色彩(或灰度)差值图像为正射影像镶嵌线检测基础,可以很好地避开色差区域,但对建筑物高密集的城区效果不明显。本文以高精度数字表面模型为检测基础,通过智能识别处理手段对地面区域与非地面区域进行良好区分。传统镶嵌线检测算法都是以迭代运算为基础的智能算法,算法复杂度高。本文发展出一种贪婪蛇型算法,该算法仅与搜索步距、方向旋转间隔、以及重叠区域宽度等三个因素相关,具有速度快,效率高等优点。针对典型的城市区域进行镶嵌线检测实验,结果表明DSM辅助下的城区正射影像镶嵌线能很好地避开房屋等明显地表实体,并且贪婪蛇型算法能有效地进行最优路径检测。