地表秸秆覆盖度图像识别技术的研究

农田地表秸秆覆盖是防止水土流失的一项主要措施,研究秸秆覆盖度与土壤风蚀、水蚀的定量关系对农田采取合理的覆盖形式有重要的指导意义。针对当前主要靠手工测试秸秆覆盖度存在效率低的问题,研究了如何应用MATLAB语言强大的图像处理功能来识别、分析秸秆图像。通过对样本图像类型的转换、灰度的均衡化和中值滤波等一系列的处理,得出较准确的秸秆覆盖面积和秸秆覆盖百分比,为准确快速测量秸秆覆盖度提供了测试手段。     

基于遗传算法的遥感数字图像镶嵌研究

遥感数字图像的镶嵌处理是遥感图像处理的基本工作之一，为此介绍了一种基于遗传算法确定图像重叠区和调整图像色度，以辅助完成遥感图像的镶嵌工作的新方法。     

基于K均值聚类的厚壁组织区域自动提取

桉树是我国南方的速生丰产林,区域提取是定量分析各种组织抑制桉树茎生根原因的重要前提。为此,介绍了基于K均值聚类的在桉树茎切片图像中自适应提取厚壁组织区域的图像处理技术。将桉树茎切片彩色图像转换为CIEL*a*b*彩色空间,用K均值聚类分析算法对描述颜色的a*和b*通道进行聚类分析,提取细胞厚壁,然后填充其中白色的细胞腔,构成完整的厚壁组织区域。实验结果表明,在CIEL*a*b*空间使用该算法可以获得较准确的实验结果。     

The effect of soil texture and organic amendment on the hydrological behaviour of coarse-textured soils

To gain more insight into the hydrological behaviour of coarse-textured soils, the physical properties of artificially created soil mixtures with different texture were determined. The mixtures were prepared according to the specifications of the United States Golf Association (USGA) for constructing putting greens. In addition, the effect of 10 vol.% organic matter addition was studied. The soil moisture retention and hydraulic conductivity relationships of the different mixtures were determined and their hydrological behaviour was studied using the numerical model SoWaM. Both texture and organic matter addition substantially affected the hydraulic properties. Hydraulic conductivity significantly increased with increasing coarseness while moisture retention decreased. On the other hand, organic matter addition reduced saturated hydraulic conductivity by a factor of 10 to 100 and distinctly increased moisture retention capacity. The amounts of total available water were increased by the addition of organic matter between 144% (slightly coarse texture) and 434% (very coarse texture). Results indicate that the mixtures can contain only 2–16% plant available water and therefore need frequent irrigation to maintain plant growth. Addition of organic matter seems a good solution to reduce the irrigation water requirements but it increases the risk of ponding or runoff because of large reductions in the saturated hydraulic conductivity sometimes to below the rate of 3.6 m/day recommended by the USGA.     

有机与无机肥料对山地梨枣品质的影响

设置不同无机肥料(氮肥、磷肥、钾肥和氮磷钾混合肥施用)、不同有机肥(沼肥和腐熟油渣肥)和不施肥(对照),研究不同施肥方法对梨枣的水分含量,总糖、可溶性固形物、还原型抗坏血酸和总抗坏血酸、质构特性以及有机酸的影响。结果表明:肥料对梨枣的水分含量没有显著性影响,显著降低了梨枣的苹果酸,柠檬酸和有机酸总含量。有机肥沼肥和腐熟油渣肥可显著提高梨枣的果皮果肉硬度和咀嚼性以及可溶性固形物、总糖含量、抗坏血酸含量,酒石酸含量却显著降低。无机肥料氮肥、磷肥、钾肥中,钾肥有利于梨枣的可溶性固形物、总糖、抗坏血酸,苹果酸和柠檬酸的含量积累,而酒石酸含量却减少。表明增施有机肥和钾肥有利于山地梨枣品质的提高。     

分形参数理论在动物CT影像处理中的研究

将分形参数理论和现代图像处理技术结合起来,对动物CT影像进行分析和处理,根据在动物骨骼的成像交界处,分形的规律性将会被破坏的基本特征,获取边界处的分形参数值H,从而判断出该处为CT图像的边界。从实验结果看,结合分形理论的分形参数算法对CT图像的处理效果优异,对家庭宠物犬和其它动物疾病的正确诊断和有效治疗提供必要的技术支撑。     

浅析几部国产电影中女性角色

2000年后,中国的电影市场逐渐繁荣。在众多的中国电影中,女性角色呈现出两种截然不同的样式：一种是呈现女性的优秀品质,另一种则是女性主义一直所反对的,将女性塑造成社会畸变的产物以吸引男性的眼光。本文通过对《非诚勿扰》、《女人不坏》、《白银帝国》、《十分完美》、《花木兰》等五部电影里的女性角色进行分析,从女性主义电影的角度将中国电影对女性角色的两极分化呈现做一个说明。     

C and N dynamics of a range of biogas slurries as a function of application rate and soil texture: a laboratory experiment

Digestates vary in composition and studies regarding their impact on C and N dynamics in soils are scarce. The objective was to analyse the C and N dynamics of digestates originating from various substrates applied to a sandy Cambisol and a silty Anthrosol. In three laboratory experiments (4–6 weeks), the effects of digestate properties, N rate and water content were tested. Averaged over both soils, 21% of the C supplied was emitted as CO₂. Potential NH₃ emissions during the first week ranged between 6% and 12% of NH₄⁺ present in the digestates. The emission factors in the sandy Cambisol were on average 1.2 and 2 times higher for CO₂ and potential NH₃, respectively, compared to the silty Anthrosol. Similarly, net nitrogen mineralization in the sandy Cambisol was approximately twice the N mineralized in the silty Anthrosol. Net nitrification was not influenced by soil texture or different digestates, but increased with increasing application rates and had highest values at 75% of water holding capacity. Our results indicate that the type of substrate input for anaerobic digestion influences the properties of the digestate and therefore the dynamics of C and N. However, soil texture can affect these dynamics markedly.     

GVF Snake模型在木材表面缺陷分割的应用研究

针对木材表面存在纹理、凹凸结构、边缘颗粒和弱边缘等特点,对其直接运用Snake模型进行分割难以得到有效边缘提取,因此提出运用改进的GVF Snake模型和维纳滤波相结合对其进行分割。首先对木材图像进行维纳滤波使得纹理变得平缓,同时可以使得缺陷边缘得到有效保留,再对其进行GVF Snake模型分割。该算法对初始轮廓的选择敏感度降低,拓展性增强,可以使得轮廓曲线更加快速地收敛到缺陷边缘,避免陷入局部最优现象,提高对弱边缘和凹凸图像分割效果,分割结果更加清晰、连贯,具有良好的实时性。为木材表面缺陷的分割提供一种更为有效的方法,拓宽了snake模型的应用范围。     

数字图像处理技术在木材微观结构研究中的应用概况

对木材微观结构的研究始终是木质材料学发展的难点，数字图像处理技术的引入不仅带来了对此问题的高效解决方案，更展示出了广阔的研究前景，分析并总结了国内外该项技术在木材微观结构研究中的进展和应用。