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排序方式: 共有1228条查询结果,搜索用时 15 毫秒
191.
玉米小斑病病害程度图像检测 总被引:8,自引:1,他引:7
为了实时获取作物病害程度信息,研究了一种基于RGB彩色模型的玉米小斑病图像的分割方法,并利用分割结果求得的玉米冠层危害程度来计算整株玉米的发病程度.由于图像中背景复杂,将叶片与病斑同时分离出来的可能性小,故该方法分为两步:首先从获取的RGB图像中提取R、G、B分量,利用2G-R-B图像采用迭代法自动选取阈值将玉米叶片从背景中分割出来;然后根据R-G图像将病斑从叶片上分离出来.30幅图像中玉米叶片、病斑基本上能提取出来,但没有黄化的少量侵染点无法有效分割. 相似文献
192.
Measurement and fissuring of rice kernels during quasi-moisture sorption by image analysis 总被引:1,自引:0,他引:1
Fissuring associated with kernel elongation was evident in a moisture-adsorbing environment at 15 °C of relative humidity 88.72±0.28% with moisture content from 6% (d.b.) to 16.3% (d.b.). The average length and width of 800 kernels was measured during the sorption test using a Cervitec Grain Inspector equipped with two digital cameras. Samples were exposed to both a moisture-adsorbing and desorbing environments at 15 °C with relative humidities of 23.4±0.53%, 55.9±0.27%, 70.98±0.28% and 88.72±0.28%. On image analysis, the kernels changed in size from 5.13 to 4.84 mm in length and 2.9 to 2.73 mm in width. Both length and width changed as expected during moisture-adsorbing and moisture-desorbing tests. Fissured kernel percent was related to changes in the average length of the kernels during the moisture-adsorbing tests. The average length and fissured kernel percent of rice kernels measured by image analysis may be considered as a reliable indicator of changes in their dimensions during quasi-static moisture sorption processes. 相似文献
193.
Baked product texture: Correlations between instrumental and sensory characterization using Flash Profile 总被引:1,自引:0,他引:1
Fifteen wheat doughs with various compositions have been selected and baked in order to obtain products with densities in the range of commercial bread values (0.25–0.35 g/cm3). A quick sensory profiling technique (Flash Profile), based on the combination of free choice profiling and a comparative evaluation of the whole product set was used. The sensory jury had to focus on the sensory perception of crumb texture (tactile and visual). The treatment of collected data by Generalized Procustes Analysis shows that products were perceived differently by the panel. The main differences concern the uniformity and the size of gas cells but also mechanical properties of corresponding crumb for which attributes like hardness, springiness and crumbliness were used. Instrumental characterization was performed using uniaxial compression (Young's modulus) and image analysis based on texture granulometry (fineness and homogeneity of cell distribution). A Multiple Factor Analysis allowed assessing the correlations between the sensory attributes and the instrumental measurements. Density and Young's modulus are positively correlated with the sensory elasticity. The instrumental and sensory measurements of the size and of the homogeneity of the cells distribution are correlated. 相似文献
194.
Guadalupe Méndez-Montealvo Francisco J. García-Suárez Octavio Paredes-López Luis A. Bello-Pérez 《Journal of Cereal Science》2008
Nixtamalization of maize grain is an ancient process that until now is used for tortilla production. This thermal-alkaline process produces important changes in morphology and rheological characteristics of starch that is the major component of maize. The aim of this study was to evaluate changes in the morphological and rheological properties of starch brought by nixtamalization of maize using image analysis and dynamic rheometry, respectively. Nixtamalized maize starch (NS) presented granule sizes higher than starch isolated from raw maize (S) due to the partial swelling produced in the nixtamalization process. In dynamic tests during the retrogradation kinetics, an inverse effect of the temperature was observed in the re-arrangement of starch components. NS was affected due to the thermal-alkaline process presenting an annealing that provoked a reduction in its ability to develop gels. This information is important during the processing of nixtamalized maize to masa and tortilla production. 相似文献
195.
196.
基于COMGIS的古树名木管理信息系统设计 总被引:3,自引:0,他引:3
阐述了如何利用组件式GIS开发平台SuperMap Objects 5.0,VB.NET编程语言,SQL Server开发古树名木管理系统的方法;探讨了系统的总体结构设计,包括技术路线、系统功能设计及数据库设计;重点分析了系统实现过程中采用的若干关键技术. 相似文献
197.
一种新的层次信息可视化模型 总被引:1,自引:0,他引:1
随着信息的日益丰富和互联网技术的发展,如何在海量数据中获取有效信息这一问题促使信息可视化领域成为当前的研究热点之一。层次信息的可视化结构最直观的方式就是树型结构。但是传统的树型结构有一个很大的缺点:当结构的层次增多或者节点增多时,该结构需要占据大量的可视化空间。针对这个问题,在分析研究层次信息可视化技术的基础上,提出了一种新的层次信息可视化模型,即层次信息自由呈递模型。通过对多种关键特征的参数化,实现层次信息在任意方向上的自由呈递,以及Focus+context视图效果。 相似文献
198.
储层表征的过程可以看成是尽可能地整合多种数据源形成储层地质知识库的过程。在储层表征过程中应用数据挖掘方法应按照原始数据及研究成果收集、数据预处理、储层知识获取、储层知识质量评估和储层知识入库等5个步骤进行。按照这5个步骤,在吐哈油田温西一区块的研究过程中应用空间叠加分析和统计学方法研究了其沉积微相与生产动态的对应关系,采用地质统计学方法定量地获取了三间房组第二砂层组的沉积微相分布知识,应用可视化方法检查了该储层模型的准确性。实践表明,应用数据挖掘方法不仅可以提高储层表征工作效率,而且可以交互验证各个阶段的储层知识,保证储层知识的完整性和正确性。 相似文献
199.
200.
林业经营管理迫切需要引入能够对林业信息进行准确、可靠、生动地描述、表现和分析的技术 .该文仅就在自主开发的FLVS系统中应用的一些方法加以介绍 .这些技术可以被用来交互式地建立森林资源可视化管理工具平台 .其中 ,商品化软件 (PHOTOSHOP和MAPINFO)中相关技术的结合可以显著提高对森林资源可视化的调控 .应用实践证明该平台可以辅助林业分析和决策 ,对林业科学管理具有重要价值 相似文献