基于RealSense深度相机的多特征树干快速识别方法

针对农业机器人在果园定位和导航中,环境背景复杂、光照强度变化大等问题,本文提出了一种基于RGB-D相机并利用颜色、深度、宽度和平行边特征的树干快速识别方法。首先,使用RealSense深度相机获取果园的彩色图像和深度数据;然后,将彩色图像转换为HSV颜色空间,再对HSV颜色空间中的S分量进行超像素分割,并将颜色特征和深度特征相近的相邻超像素块进行合并;随后,对深度图像进行树干宽度特征检测,对宽度置信率大于阈值的物体看作是待处理物体;最后,对待处理的物体进行平行边特征检测,在待处理物体边缘区域选择感兴趣区域窗口（ROI）进行边缘检测,搜索可能的树干边缘直边,当物体边缘的置信率R_B大于设定的阈值T_LB时,则识别为树干。通过对树干的多特征提取,有效提高了在不同环境下树干识别准确率。利用移动机器人平台在果园环境进行试验测试,以检验在强光照、正常光照和弱光照条件下树干识别算法的性能。试验结果表明,本文的树干识别算法在强光照、正常光照和弱光照条件下,树干识别的准确率分别为92.38%、91.35%和89.86%,每帧图像平均耗时分别为0.54、0.66、...     

基于双目相机与改进YOLOv3算法的果园行人检测与定位

针对复杂果园环境中行人难以精确检测并定位的问题,提出了一种双目相机结合改进YOLOv3目标检测算法的行人障碍物检测和定位方法。该方法采用ZED双目相机采集左右视图,通过视差原理获取图像像素点的距离信息;将双目相机一侧的RGB图像作为用树形特征融合模块改进的YOLOv3算法的输入,得到行人障碍物在图像中的位置信息,结合双目相机获得的像素位置信息计算出相对于相机的三维坐标。用卡耐基梅隆大学国家机器人工程中心开放的果园行人检测数据集测试改进的YOLOv3算法,结果表明,准确率和召回率分别达到95.34%和91.52%,高于原模型的94.86%和90.19%,检测速度达到30.26 f/ms。行人检测与定位试验表明,行人障碍物的定位在深度距离方向平均相对误差为1.65%,最大相对误差为3.80%。该方法具有快速性和准确性,可以较好地实现果园环境中的行人检测与定位,为无人驾驶农机的避障决策提供依据。     

基于图像处理的果树滴水线导航路径检测方法研究

针对果园开沟施肥,提出一种基于图像处理的果树滴水线导航路径检测方法。该方法采用垂直地面向上布置的CCD相机采集果树冠层投影图像,并实现果树冠层沿地面垂直投影轮廓的识别与滴水线平滑处理,进而对无人施肥装备沿果树环状行走路径进行确定。通过相机标定获取相机内部参数和畸变参数,对原始图像进行畸变矫正;通过对图像在RGB颜色空间的分布特征进行定量分析,使用平均值法对图像灰度处理,使用定阈值法进行二值分割;二值图像中由于存在大量的空间间隙,使用形态学膨胀操作,填充间隙,以凸显树冠投影边缘轮廓;使用边界跟踪算法,提取树冠轮廓边缘;引入Beseel曲线拟合方法,对轮廓边缘进行平滑处理,通过对比二阶、三阶、四阶、五阶拟合结果,得出使用三阶和四阶Beseel拟合结果较为符合导航路径要求。将相机固定在一个位置,分别在晴天和阴天拍摄条件下采集图像,进行滴水线导航路径提取,分别使用三阶和四阶Beseel曲线拟合晴天和阴天的图像边缘轮廓,使用四阶拟合结果较为符合实际要求,平均像素误差为19.5像素,平均像素相对误差为2.6%,平均每帧图像处理速度为27 ms,能较好地满足导航精度和实时性的要求,为施肥作业平台沿滴水线自动导航提供参考。     

基于Mask R-CNN的猪只爬跨行为识别

针对目前猪只爬跨行为自动化检测程度较低的问题,提出了一种基于Mask R-CNN的猪只爬跨行为识别算法。首先获取猪只俯视图像,利用Labelme制作数据集标签,引入迁移学习方法训练Res Net-FPN网络,获取猪只分割结果,并提取每个样本中的mask像素面积。提取每个样本中的最小mask像素面积作为爬跨行为识别的经验样本集,确定爬跨行为界定阈值。利用测试集分别测试猪只分割网络模型及爬跨行为识别算法,结果表明,猪只分割网络模型的分割准确率为94%,爬跨行为识别算法准确率为94. 5%。本算法能够自动有效地检测猪只爬跨行为,可为牲畜养殖自动化提供支持。     

基于多光谱图像的库尔勒香梨表面缺陷检测

表面缺陷会导致水果腐烂,降低商业经济价值,引发食品质量和安全问题。为此,利用机器视觉技术检测果皮表面缺陷是水果采后加工的主要任务之一。然而,由于香梨果皮颜色及缺陷多样性,用图像处理方法检测库尔勒香梨表面缺陷较为困难。为实现快而准确的香梨缺陷检测,提出一种基于多光谱图像的库尔勒香梨表面缺陷检测方法,并研究了疤痕、病害、虫咬、碰压伤、机械损伤及果锈6种表面缺陷情况。同时,设计了一种基于多光谱图像的库尔勒香梨表面缺陷面积计算方法,通过统计缺陷区域像素个数来代替缺陷面积。按照国标GB/T19859-2005规定:选定缺陷面积大于0.8cm~2作为缺陷果的判别依据进行试验,结果表明:带有疤痕、病斑和腐烂缺陷的缺陷识别准确率可达到92%以上,处理单张图像平均耗时2.4s,具有较高准确性,可用于库尔勒香梨的实时检测。     

基于线阵扫描图像的玉米果穗性状检测技术

为实现玉米果穗性状自动检测,以线阵扫描方式获取玉米果穗表面圆周图像信息,利用图像处理技术从中提取相关性状参数。从扫描图像自身提取检测模板,应用归一化互相关算法完成玉米果穗单周图像的精确切割;以Otsu法完成籽粒分割后,利用边界非完整籽粒的连接性,完成边界分割籽粒的合并,提高籽粒计数准确度;采用图像投影曲线平滑后求极值的方法获取穗行数。与人工检测实验结果对比,穗粒数和穗行数的计数准确率分别为94.6%和99.1%。     

球形水果表面斑块成像失真度控制与实验

针对机器视觉在线分选时球形水果表面缺陷斑块在图像中形状、尺寸失真的问题,依据射影几何原理和通用成像配置,建立了斑块的成像普遍方程及斑块成像面积的通用算法,分析了斑块图像的面积失真规律;利用Matlab建立了满足特定分选准确度要求下有效采像区域与成像系统参数的配置关系,提出了一种有效采像区域的简化划定方法;分别以半球块和埃及甜橙为实验对象,利用NI Vision Assistant对工业相机采集到的、位于划定区域内的缺陷斑块进行了面积失真度校验。实验结果表明,特定采像条件下,当失真度阈值A为20%时,求得最小球心角λ_(0 min)为79. 32°来划定有效采像区域,采集到的5个半球块位于不同采像工位及其对应的采像姿态下的图像,有效采像区域内各缺陷斑块面积失真度均小于20%,满足失真度控制要求;同样地,5个埃及甜橙样本中,满足失真度要求的缺陷斑块比例分别达:97. 38%、97. 33%、94. 22%、96. 44%、97. 78%。可见,利用球形水果表面缺陷斑块成像普遍方程预测结果进行图像的有效采像区域分割,即可实现对分选准确率的有效控制;通过测定有效采像区域中缺陷斑块面积进行分选阈值判断,有利于简化图像处理计算,为球形水果成像系统成像参数配置提供理论指导。     

基于计算机视觉的鸡蛋裂纹检测方法研究

为了提高鸡蛋壳裂纹检测的准确性和效率,综合应用了计算机视觉技术,实现对鸡蛋表面裂纹的检测。在利用计算机视觉系统获取鸡蛋表面图像后,采用同态滤波、BET算法、fisher等改进型图像处理技术,提取裂纹特征并判决。试验结果表明,模型对裂纹鸡蛋的识别准确率达到了98%。     

基于Mask-RCNN的自然场景下油茶果目标识别与检测

针对我国油茶果采摘过程中存在的自动化水平落后、采摘效率低、适采周期短的现状,应用于机器人收获技术的机器视觉技术受限于真实场景中复杂背景干扰从而导致识别精度较低的问题。以自然场景下的油茶果为研究对象,提出一种基于Mask-RCNN的自然场景下油茶果目标识别与检测算法,首先获取油茶果图像并建立数据集,利用ResNet卷积神经网络提取油茶果果实图片的特征,获得果实目标分割结果,再采用RPN对所得到的特征图进行操作,并增加全连接层,提取每个样本mask像素面积,并对目标类别进行预测。利用测试集分别测试油茶果的分割网络模型及目标识别算法,结果表明,网络模型的分割准确率为89.85%,油茶果目标识别的平均检测精度为89.42%,召回率为92.86%。本算法能够自动检测油茶果目标,并有效降低不同光照情况下叶片与花苞遮挡、果实重叠、果实色泽等因素干扰,为自然场景中果实自动化采摘提供可靠的视觉支持。     

油茶果的模糊聚类色选算法

通过研究油茶果籽和皮的颜色特性,将线阵工业相机采集的油茶果籽和皮图像分割成若干正方形像素块,基于模糊聚类原理,根据特征降维、一致性度量和模式识别的相关理论,研究油茶果的颜色识别分类方法,实现一种基于彩色线阵相机的动态模糊聚类色选算法,并将算法应用于通道式单面色选机的预选和实时分选程序中。应用表明,算法对新鲜的油茶果籽分选选净率达到98%。     

Overland water and salt flows in a set of rice paddies

Cultivation of paddy rice in semiarid areas of the world faces problems related to water scarcity. This paper aims at characterizing water use in a set of paddies located in the central Ebro basin of Spain using experimentation and computer simulation. A commercial field with six interconnected paddies, with a total area of 5.31 ha, was instrumented to measure discharge and water quality at the inflow and at the runoff outlet. The soil was classified as a Typic Calcixerept, and was characterized by a mild salinity (2.5 dS m⁻¹) and an infiltration rate of 5.8 mm day⁻¹. The evolution of flow depth at all paddies was recorded. Data from the 2002 rice-growing season was elaborated using a mass balance approach to estimate the infiltration rate and the evolution of discharge between paddies. Seasonal crop evapotranspiration, estimated with the surface renewal method, was 731 mm (5.1 mm day⁻¹), very similar to that of other summer cereals grown in the area, like corn. The irrigation input was 1874 mm, deep percolation was 830 mm and surface runoff was 372 mm. Irrigation efficiency was estimated as 41%. The quality of surface runoff water was slightly degraded due to evapoconcentration and to the contact with the soil. During the period 2001–2003, the electrical conductivity of surface runoff water was 54% higher than that of irrigation water. However, the runoff water was suitable for irrigation. A mechanistic mass balance model of inter-paddy water flow permitted to conclude that improvements in irrigation efficiency cannot be easily obtained in the experimental conditions. Since deep percolation losses more than double surface runoff losses, a reduction in irrigation discharge would not have much room for efficiency improvement. Simulations also showed that rice irrigation performance was not negatively affected by the fluctuating inflow hydrograph. These hydrographs are typical of turnouts located at the tail end of tertiary irrigation ditches. In fact, these are the sites where rice has been historically cultivated in the study area, since local soils are often saline-sodic and can only grow paddy rice taking advantage of the low salinity of the irrigation water. The low infiltration rate characteristic of these saline-sodic soils (an experimental value of 3.2 mm day⁻¹ was obtained) combined with a reduced irrigation discharge resulted in a simulated irrigation efficiency of 60%. Paddy rice irrigation efficiency can attain reasonable values in the local saline-sodic soils, where the infiltration rate is clearly smaller than the average daily rice evapotranspiration.     

瓦房店市水果生产标准化发展研究

瓦房店市是我国重要的水果生产基地,在国内水果生产领域占有重要地位。随着水果市场化的不断深入,如何满足和适应国内外市场需求成为瓦房店市水果生产的关键问题。从瓦房店市水果生产实际出发,阐述了实施水果生产标准化的必要性,提出了发展水果生产标准化的具体措施。     

金谷子耐旱TG118引种试种及推广应用

对引进的谷子新品种金谷子耐旱TG118进行品种比较试验和多点试种。结果表明：该品种抗旱、耐瘠、适应性强,稳产、高产、抗病抗风抗倒伏强,品质优良,粮草兼用,种植简单,省工易管;一般产量在6000kg/hm2以上,比当地主栽品种增产20%以上。最高产量达9450kg/hm2,适于在辽西北地区推广应用。     

对《种子法》存在问题的探讨

《种子法》是我国种植业第一部法律。自实施以来,为依法加强种子管理提供了有力的法律支撑,促进我国种子产业发生翻天覆地的变化。但随着依法管理工作的深入和种子产业的快速发展,《种子法》及配套规章的一些问题逐步显现出来。对《种子法》及配套规章存在的问题进行深入分析,对需要进一步补充的章节以及需要调整的内容进行深入探讨,以求更加完善和明确。     

Review of the Egyptian experience in implementing land drainage projects

About 30 years have passed since the Government of Egypt embarked on implementing a series of large scale drainage projects. At present, about 3.8 million acres have been provided with drainage systems on the basis of systematic pre-drainage investigations and designs. The target is to provide drains in approximately 6.4 million acres in the Nile Valley and Delta.The implementation of the subsurface drainage system is carried out by the public sector and private contractors under direct supervision of governmental regional departments. The implementation process depends on many factors related to the drainage material, machinery, manpower, site requirements, farmers and organizations involved. Problems and constraints are sometimes challenging, however, the annual rate of implementation has gradually increased to 170,000 acre/year.This paper discusses the different aspects involved in the implementation process of drainage systems. The development in materials, machinery and construction technologies will be reviewed. Institutional and management factors are going to be also considered.     

和谐社会理论建设的几点哲学思考

在新世纪,面对机遇和挑战,党的十六大把“社会更加和谐”作为全面建设更高水平的小康社会的一个重要目标。中国人素有社会和谐的理想;西方人自古也向往社会和谐;借鉴东西方两种和谐社会思想的经验、教训,构建社会主义和谐社会理论。     

A European irrigation map for spatially distributed agricultural modelling

We present a pan-European irrigation map based on regional European statistics, a European land use map and a global irrigation map. The map provides spatial information on the distribution of irrigated areas per crop type which allows determining irrigated areas at the level of spatial modelling units. The map is a requirement for a European scale assessment of the impacts of irrigated agriculture on water resources based on spatially distributed modelling of crop growth and water balance. The irrigation map was compiled in a two step procedure. First, irrigated areas were distributed to potentially irrigated crops at a regional level (European statistical regions NUTS3), combining Farm Structure Survey (FSS) data on irrigated area, crop-specific irrigated area for crops whenever available, and total crop area. Second, crop-specific irrigated area was distributed within each statistical region based on the crop distribution given in our land use map. A global map of irrigated areas with a 5′ resolution was used to further constrain the distribution within each NUTS3 based on the density of irrigated areas. The constrained distribution of irrigated areas as taken from statistics to a high resolution dataset enables us to estimate irrigated areas for various spatial entities, including administrative, natural and artificial units, providing a reasonable input scenario for large-scale distributed modelling applications. The dataset bridges a gap between global datasets and detailed regional data on the distribution of irrigated areas and provides information for various assessments and modelling applications.     

粉质仪和拉伸仪在面粉生产中的应用

在介绍粉质仪和拉伸仪结构和原理的基础上,探讨了粉质曲线中吸水率、形成时间、稳定时间、弱化度和评价值等指标与面粉品质的关系,以及如何根据拉伸曲线中面团最大拉伸阻力、延伸度和拉伸曲线面积等指标来评价面团品质,并结合生产实际,概述了粉质仪和拉伸仪在面粉生产中的作用。     

农村信息化服务的现状及建设措施

分析当前我国农村信息化服务的现状,提出加强农村信息化服务的新举措。     

车辆ABS控制算法的研究及探讨

对现代汽车的ABS控制算法作了一些简单的介绍,同时指出了它们的一些缺陷,相应地提出了几种对ABS的其它控制方法并加以探讨,其中着重论述了ABS门限值控制算法中参考车速的确定方法和基于附着系数的控制算法。