温室环境视觉导航路径的识别

为实现视觉导航的精确性和鲁棒性,研究了温室复杂环境机器人视觉导航路径的识别方法。以温室内西红柿苗垄为研究对象,在地膜、光线和阴影等复杂环境对植物识别的影响下,用Lab色彩空间将绿色植物从背景中分离出来;用基于权重因子的阈值分割算法代替常用的阈值分割算法;用改进的Hough变换的导航线提取方法处理有杂草干扰的作物垄。试验证明,该方法对复杂温室环境下作物垄导航线的提取有较好的适应性,而且算法简单,能够满足实时性的要求。     

温室环境下黄瓜采摘机器人信息获取

研究基于近红外图像的黄瓜果实与茎叶的信息表达方法,有效实现了近色系生物信息的图像识别。分析了黄瓜采摘深度图像信息的特点,通过建立基于灰度相关与极线几何相结合的匹配策略实现了双目视觉下的黄瓜抓取点的立体匹配和三维重建。研究温室环境下不同时间光照强度变化特点,建立了光照分析模型,提高了不同光照条件下的导航线提取的适应性。试验表明机器人视觉系统能有效识别、定位果实的空间位置,定位误差控制在±     

温室环境下黄瓜采摘机器人信息获取

研究基于近红外图像的黄瓜果实与茎叶的信息表达方法,有效实现了近色系生物信息的图像识别。分析了黄瓜采摘深度图像信息的特点,通过建立基于灰度相关与极线几何相结合的匹配策略实现了双目视觉下的黄瓜抓取点的立体匹配和三维重建。研究温室环境下不同时间光照强度变化特点,建立了光照分析模型,提高了不同光照条件下的导航线提取的适应性。试验表明机器人视觉系统能有效识别、定位果实的空间位置,定位误差控制在±5mm以内。     

自然光照下基于粒子群算法的农业机械导航路径识别

针对农业机械视觉导航线提取易受光照变化影响及常规导航线识别算法实时性低、抗干扰能力差等问题,对自然光照条件下基于机器视觉的农业机械导航路径识别技术进行了研究。首先,在YCr Cb颜色模型的基础上构建与光照无关的Cg分量,选择2Cg-Cr-Cb特征因子对图像进行灰度化处理,以降低光照变化对图像分割的影响;然后,采用改进K-means聚类方法进行图像分割,将绿色作物信息从土壤背景中分离出来,并通过形态学滤波方法滤除二值图像中存在的杂草干扰信息;最后,根据图像中作物行的特点建立作物行直线方程约束模型,利用粒子群算法对作物行直线进行寻优求解,进而得到导航线。实验结果表明,不同光照条件下对2Cg-Cr-Cb灰度图像进行图像分割,可以清晰完整地将作物从土壤背景中分离出来,分割图像受光照变化影响较小并且不会引入背景噪声;基于粒子群算法的导航线检测方法可以快速准确地提取出导航路径,对于不同农田作物和作物不同生长阶段具有较高的适应性,相比于常规导航线识别算法具有实时性高、鲁棒性好等优点。     

农业车辆视觉实际导航环境识别与分

分析了对路径识别影响较大的变光照环境、杂草环境和阴影环境对农业车辆导航路径的影响,提出一种实际环境中的农业车辆视觉导航研究方法,即先采用神经网络算法对农田环境进行自动分类,然后再相应的选择不同的路径识别方法进行处理.环境识别与分类试验结果证明,该方法能够提高农业车辆视觉导航系统的实用性和可靠性,导航环境的分类准确率为95%,单幅图像平均耗时23 ms.     

基于动态图像阈值的智能车辆路径导航

使用机器视觉技术进行智能车辆车道路径识别时,其识别效果易受光照等外界因素的影响.考虑到条带状的导航路径在获取的路径图像中的宽度应该在一个固定范围内,可以根据使用某一图像阈值识别路径后该路径的横向宽度判定先前使用的阈值是否适合,并进行相应调整,从而获取到适合各种环境的动态阈值.在给出动态图像阈值的获取流程及实现方法的基础上,对智能车辆车道路径识别和跟踪系统进行了软硬件设计,并进行实车道路试验.试验结果表明,与一般最优阈值算法相比,提出的动态阈值方法能够在各种光照条件下,尤其是强光照下准确地识别导航路径,且路径跟踪具有较好的精确性和鲁棒性.     

温室农用机器人的路径检测

为实现温室中基于单目视觉的机器人自适应导航,运用Susan算子点检测的方法,融合Hough变换,提出了温室环境中的路径导航线的生成算法,并将标准Susan算子改造成适应与Hough变换的二值化形式.通过对温室中113幅图像进行实验检测可知,采用此方法可有效地检测机器人导航路径,且路径检测的识别率为94%,平均导航角为0.192 2°.     

基于最小二乘法的温室番茄垄间视觉导航路径检测

针对温室非结构作业环境和复杂背景下作业机器人路径识别检测问题开展研究。在HSI颜色空间分析番茄垄间道路图像在各分量的分布特性,提出了基于机器视觉的垄间加热管敏感区域提取方法,依据I分量直方图采用最大类间方差法进行图像自适应阈值分割,对分割后二值图像利用目标区域的边缘提取算法获得导航离散点簇。根据最小二乘法原理对导航离散点簇拟合得到2条加热管边缘线,在此基础上给出中心导航基准线检测算法,并针对光照不均和作物遮挡对导航路径检测进行了实验。实验表明,与Hough变换算法相比,该算法简单快速,对光照不均具有良好的鲁棒性,能够准确提取目标敏感区域的边缘信息,对不同遮盖率番茄垄间导航路径提取正确率达91.67%。     

复杂背景下果园视觉导航路径提取算法

为解决果园视觉导航机器人行间自主行进和调头问题,提出了基于Mask R-CNN的导航线提取方法和基于随机采样一致性(Random sample consensus, RANSAC)算法的树行线提取方法。首先,基于Mask R-CNN模型对道路与树干进行识别,提取道路分割掩码和树干边界框坐标;其次,在生成行间导航线的基础上,采用改进RANSAC算法提取前排树行线;然后,计算树干边界框坐标点到前排行线的距离,筛选后排树干坐标点,采用最小二乘法拟合生成后排树行线;最后,通过分析前后排树行信息判断调头方向,结合本文提出的行末端距离计算与调头路径规划方法,规划车辆的调头路线。实验结果表明：在不同光照、杂草、天气环境下的6种果园场景中,模型的平均分割精度和边界框检测精度都为97.0%,导航目标点提取的平均偏差不超过5.3%,树行线检测准确率不低于87%,调头后车辆距道路中心的平均偏差为7.8 cm,可为果园环境下的视觉自主导航提供有效参考。     

基于U-Net网络的果园视觉导航路径识别方法

针对视觉导航系统在果园环境中面临的图像背景复杂、干扰因素多等问题,提出了一种基于U-Net网络的果园视觉导航路径识别方法。使用Labelme对采集图像中的道路信息进行标注,制作果园数据集;基于U-Net语义分割算法在数据增强的基础上对全卷积神经网络进行训练,得到道路分割模型;根据生成的道路分割掩码进行导航信息提取,生成路径拟合中点;基于样条曲线拟合原理对拟合中点进行多段三次B样条曲线拟合,完成导航路径的识别;最后进行了实验验证。结果表明,临界阈值为0.4时,语义分割模型在弱光、普通光以及强光照条件下的分割交并比分别为89.52%、86.45%、86.16%,能够平稳实现果园道路像素级分割;边缘信息提取与路径识别方法可适应不同视角下的道路掩码形状,得到较为平顺的导航路径;在不同光照和视角条件下,平均像素误差为9.5像素,平均距离误差为0.044 m,已知所在果园道路宽度约为3.1 m,平均距离误差占比为1.4%;果园履带底盘正常行驶速度一般在0～1.4 m/s之间,单幅图像平均处理时间为0.154 s。在当前果园环境和硬件配置下,本研究可为视觉导航任务提供有效参考。     

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。