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Spatial-temporal differentiation and influencing factors of rural settlements in mountainous areas: an example of Liangshan Yi Autonomous Prefecture, Southwestern China

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Journal of Mountain Science 2024年第1期21卷 218-235页

作者： WANG Yumeng DENG qingchun YANG Haiqing LIU Hui YANG feng ZHAO Yakai School of Geographical Sciences China West Normal UniversityNanchong 637009China Sichuan Provincial Engineering Laboratory of Monitoring and Control for Soil Erosion in Dry Valleys China West Normal UniversityNanchong 637009China Liangshan Soil Erosion and Ecological Restoration in Dry Valleys Observation and Research Station Xide 616753China

Rural settlement is the basic spatial unit for compact communities in rural area. Scientific exploration of spatial-temporal differentiation and its influencing factors is the premise of spatial layout rationalization. Based on land use data of Liangshan Yi Autonomous Prefecture(hereinafter referred to as Liangshan Prefecture) in Sichuan Province, China from 1980 to 2020, compactness index, fractal dimension, imbalance index, location entropy and the optimal parameters-based geographical detector(OPGD) model are used to analyze the spatial-temporal evolution of the morphological characteristics of rural settlements, and to explore the influence of natural geographical factors, socioeconomic factors, and policy factors on the spatial differentiation of rural settlements. The results show that:(1) From 1980 to 2020, the rural settlements area in Liangshan Prefecture increased by 15.96 km^(2). In space, the rural settlements are generally distributed in a local aggregation, dense in the middle and sparse around the periphery. In 2015, the spatial density and expansion index of rural settlements reached the peak.(2) From 1980 to 2020, the compactness index decreased from 0.7636 to 0.7496, the fractal dimension increased from 1.0283 to 1.0314, and the fragmentation index decreased from 0.1183 to 0.1047. The spatial morphological structure of rural settlements tended to be loose, the shape contour tended to be complex, the degree of fragmentation decreased, and the spatial distribution was significantly imbalanced.(3) The results of OPGD detection in 2015 show that the influence of each factor is slope(0.2371) > traffic accessibility(0.2098) > population(0.1403) > regional GDP(0.1325) > elevation(0.0987) > poverty alleviation(0). The results of OPGD detection in 2020 show that the influence of each factor is slope(0.2339) > traffic accessibility(0.2198) > population(0.1432) > regional GDP(0.1219) > poverty alleviation(0.0992) > elevation(0.093). Natural geographical facto

关键词： Rural settlements Location entropy Geographical detector Spatiotemporal differentiation Influencing factors

Design of structured-light vision system for tomato harvesting robot

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International Journal of Agricultural and Biological Engineering 2014年第2期7卷 19-26页

作者： feng qingchun Cheng Wei Zhou Jianjun Wang Xiu Beijing Research Center of Intelligent Equipment for Agriculture Beijing 100097China Zhejiang University of Technology Hangzhou 100085China

In order to improve the operating precision of the harvesting robot,a vision system for intelligently identifying and locating the mature tomato was *** active detection method based on structured-light stereo vision was expected to deal with the problem of variable illumination and target occlusion in the *** maximum between-cluster variances of hue(H)and saturation(S)value were adopted as the threshold for color segmentation,which weakened the impact on the image caused by the light intensity *** the limit on the pixel size and circularity of the candidate areas,the vision system recognized the fruit area and removed the noise *** fruit’s 3D position was computed on the basis of spatial relationship between the laser plane and the camera,when the linear laser was projected on the centre area of the mature *** blue view-scanning laser stripe pixels on the mature fruit were extracted according to its Cb color *** the field test results show,the measurement error on the fruit radius is less than 5 mm,the centre distance error between the fruit and camera is less than 7 mm,and the single axis coordinate error is less than 5.6 *** structured-light vision system could effectively identify and locate mature fruit.

关键词： harvesting robot tomato linear structure-light 3D measurement feature extraction

Design and test of tray-seedling sorting transplanter

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International Journal of Agricultural and Biological Engineering 2015年第2期8卷 14-20页

作者： feng qingchun Zhao Chunjiang Jiang Kai Fan Pengfei Wang Xiu Beijing Research Center of Intelligent Equipment for Agriculture Beijing 100097China

In order to improve the automatic sorting and transplanting of tray-seedling and reduce labors strength,a new sorting transplanter was *** to the feature of normal seedling tray and manual grading method,the mechanical sorting procedure was *** key parts of sorting transplanter are as follows:an efficient transfer mechanism with aerodynamic buffer,a seedling identifying and measuring unit based on linear-structured vision,the extendible multi-grasper with wireless technology and the system *** experiments were conducted and showed that the transplanting success rate was 90.0% on the tray of 6×12 holes under the speed of 700 cycles per *** vision unit’s failed identifying rate for the superior pepper seedlings on five different trays was less than 10%,and the measurement error of seedling height was about 5 mm.

关键词： transplanter tray seedling sorting grasper machine vision wireless technology

Design and test of robotic harvesting system for cherry tomato

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International Journal of Agricultural and Biological Engineering 2018年第1期11卷 96-100页

作者： qingchun feng Wei Zou Pengfei Fan Chunfeng Zhang Xiu Wang Beijing Research Center of Intelligent Equipment for Agriculture Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China National Research Center of Intelligent Equipment for Agriculture Beijing 100097China Beijing Key Laboratory of Intelligent Equipment Technology for Agriculture Beijing 100097China

Harvesting of fresh-eating cherry tomato was highly costly on labor and *** order to achieve mechanical harvesting for the fresh-eating tomato,a new harvesting robot was designed,which consisted of a stereo visual unit,an end-effector,manipulator,a fruit collector,and a railed *** robot configuration and workflow design focused on the special cultivating *** key parts were introduced in detail:a railroad vehicle capably moving on both ground and rail was adopted as the robot’s carrier,a visual servo unit was used to identify and locate the mature fruits bunch,and the end-effector to hold and separate the fruit bunch was designed based on the stalk’s mechanical *** field test of the new developed robot was conducted and the results were *** successful harvest rate of the robot was 83%,however,each successful harvest averagely needed 1.4 times attempt,and a single successful harvesting cycle cost 8 s excluding the time cost on moving.

关键词： cherry tomato harvesting robot visual servo configuration design field test

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石油产品中硫含量测定方法适用性研究

齐鲁石油化工 2023年第1期51卷 78-83页

作者：冯庆春中国石化齐鲁分公司检验计量中心山东淄博255436

本文通过分析我国石油产品标准中规定的硫含量分析方法,明确各种方法的适用性,并对常用的能量色散X射线荧光光谱法、电量法、单波长色散X射线荧光光谱法和紫外荧光法四种测定方法的重复性进行试验,提出石油产品中硫含量检测的选择方法,... 详细信息

本文通过分析我国石油产品标准中规定的硫含量分析方法,明确各种方法的适用性,并对常用的能量色散X射线荧光光谱法、电量法、单波长色散X射线荧光光谱法和紫外荧光法四种测定方法的重复性进行试验,提出石油产品中硫含量检测的选择方法,为不同石油产品的硫含量测定方法的选择提供参考依据,在实际工作中提高分析的准确度。

关键词：石油产品硫含量测定适用性

基于Mask R-CNN的番茄植株整枝操作点定位方法

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农业工程学报 2022年第3期38卷 128-135页

作者：冯青春成伟李亚军王博文陈立平北京市农林科学院智能装备技术研究中心北京100097 国家农业智能装备工程技术研究中心北京100097 农业智能装备技术北京市重点实验室北京100097

针对工厂化番茄智能化整枝打叶作业需要,研究了基于MaskR-CNN模型的整枝操作点识别定位方法,以期为整枝机器人的精准操作提供依据。鉴于丛生植株中主茎和侧枝茎秆目标随机生长、形态各异,结合植株在不同生长阶段、远近视场尺度和观测视... 详细信息

针对工厂化番茄智能化整枝打叶作业需要,研究了基于MaskR-CNN模型的整枝操作点识别定位方法,以期为整枝机器人的精准操作提供依据。鉴于丛生植株中主茎和侧枝茎秆目标随机生长、形态各异,结合植株在不同生长阶段、远近视场尺度和观测视角等条件下的成像特征,构建了温室番茄植株图像样本数据集。采用学习率微调训练方法,对Mask R-CNN预训练模型进行迁移训练,建立了主茎和侧枝像素区域的识别分割模型。在对视场内同株相邻主茎和侧枝目标进行判别基础上,提出基于图像矩特征的茎秆中心线拟合方法。以中心线交点为参考,沿侧枝进行定向偏移,实现对整枝操作点图像坐标的定位。最后,通过测试试验评估该方法对目标识别和定位的效果。试验结果表明,模型对番茄主茎和侧枝目标识别的错误率、精确率和召回率分别为0.12、0.93和0.94,对整枝操作点平均定位偏差与对应主茎像素宽度的比值为0.34,模型对于近景仰视图像中目标的识别和定位效果优于其他视场的图像。该研究可为整枝机器人视觉系统的研发提供技术依据。

关键词：农业机器人番茄整枝植株茎秆 Mask R-CNN

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农业机器人技术进展、挑战与趋势

智慧农业（中英文） 2023年第4期5卷 1-15页

作者：赵春江范贝贝李瑾冯青春北京市农林科学院信息技术研究中心北京100097 北京市农林科学院智能装备技术研究中心北京100097

[目的/意义]农业机器人是全球农业装备的战略制高点和竞争焦点,也是加快推动中国农业强国建设的重点方向之一。世界农业强国与中国均围绕本国农业发展特点,正在加强农业机器人政策与规划布局,带动农业机器人产业进入稳定增长期。[进展]... 详细信息

[目的/意义]农业机器人是全球农业装备的战略制高点和竞争焦点,也是加快推动中国农业强国建设的重点方向之一。世界农业强国与中国均围绕本国农业发展特点,正在加强农业机器人政策与规划布局,带动农业机器人产业进入稳定增长期。[进展]本文阐述了农业机器人概念及特征,全球农业机器人发展政策与战略规划布局,以及产业发展状况。针对农田作业机器人、果园采摘机器人和设施蔬菜生产机器人等3类典型农业机器人的产业背景、前沿进展、发展面临的挑战和关键技术卡点开展了深入分析。[结论/展望]展望了在全球农业劳动力的日益短缺的大背景下,农业机器人产业快速发展面临的机遇,提出了未来农业机器人技术在自主导航、自主学习、实时监控、作业管控等方面的发展趋势。

关键词：农业机器人智能农机精准作业无人农场自主导航

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面向番茄自动整枝的茎秆夹持力学特性测量与分析

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农机化研究 2023年第12期45卷 157-163页

作者：王博文张万豪冯青春新疆农业大学机电工程学院乌鲁木齐830052 北京市农林科学院智能装备技术研究中心北京100097 国家农业智能装备工程技术研究中心北京100097 农业智能装备技术北京市重点实验室北京100097

获取番茄植株的茎秆外观形态和组织力学特性是设计自动化整枝执行机构的重要依据。为此,以“佳丽14”番茄品种作为研究对象,通过实地测量获取番茄植株茎秆自然形态参数,基于MTS E43型电子万能试验机对茎秆力学特性进行测量,获得番茄茎... 详细信息

获取番茄植株的茎秆外观形态和组织力学特性是设计自动化整枝执行机构的重要依据。为此,以“佳丽14”番茄品种作为研究对象,通过实地测量获取番茄植株茎秆自然形态参数,基于MTS E43型电子万能试验机对茎秆力学特性进行测量,获得番茄茎秆挤压、剪切及离层断裂等力学特性参数。根据对茎秆施加不同正压力时产生的最大静摩擦力,采用最小二乘法分别估算了其与不锈钢、PVC、硬质橡胶及硅胶等4种典型工程材料的最大静摩擦因数;同时,为了实现对番茄植株侧枝安全夹持与可靠分离,结合对茎秆离层断裂与夹持压溃时临界力约束,确定了番茄植株侧枝夹持柔性材料的硬度与弹性模量。研究结果可以为设施农业番茄自动化整枝及整枝机器人关键执行部件的设计提供理论依据。

关键词：番茄茎秆蔬菜整枝柔性夹持力学特性末端执行器

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老年重症心脏瓣膜疾病患者术后发生低心排血量综合征危险因素分析

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心血管病学进展 2022年第11期43卷 1043-1049页

作者：柴晓利张臣丰庆春湖南省脑科医院心血管内科湖南长沙410015

目的探讨老年重症心脏瓣膜疾病患者术后发生低心排血量综合征(LCOS)的相关危险因素。方法选取2015年7月—2022年1月于湖南省脑科医院行心脏瓣膜手术的重症心脏瓣膜疾病患者251例作为研究对象,采用计算机产生随机数法以2:1的比例分为训练... 详细信息

目的探讨老年重症心脏瓣膜疾病患者术后发生低心排血量综合征(LCOS)的相关危险因素。方法选取2015年7月—2022年1月于湖南省脑科医院行心脏瓣膜手术的重症心脏瓣膜疾病患者251例作为研究对象,采用计算机产生随机数法以2:1的比例分为训练集(167例)和测试集(84例),对患者进行心脏瓣膜置换术,依据训练集患者术后是否发生LCOS将其分为LCOS组(n=45)和非LCOS组(n=122)。采用单因素分析和多因素逻辑回归分析对两组患者的临床资料进行统计分析。根据多因素分析结果利用R 3.6.0软件建立模型,并采用受试者操作特征(ROC)曲线、一致性指数(CI)以及卷积神经网络(CNN)对预测模型进行验证。结果术后45例患者发生LCOS,单因素和多因素逻辑回归分析表明:患者年龄、术前纽约心功能分级Ⅳ级、体外循环时间和失血比是术后发生LCOS的独立危险因素。根据多因素分析结果构建列线图预测模型并对模型进行验证,训练集列线图模型的ROC曲线下面积(AUC)为0.743(95%CI 0.692~0.817),测试集的AUC为0.712(95%CI 0.684~0.823),模型的区分度良好;训练集的CI为0.736(95%CI 0.683~0.865),测试集CI为0.745(95%CI 0.640~0.812),CNN显示在300个周期后错误率逐渐稳定,模型准确性良好,预测能力较强。结论老年重症患者的脏器功能处于代偿边缘,属高危人群,为降低老年重症患者心脏瓣膜手术后出现LCOS的概率,术前准备充分,尽量缩短体外循环时间和主动脉阻断时间,减少术中出血量,加强心肌保护等措施十分必要。

关键词：老年重症心脏瓣膜疾病低心排血量综合征危险因素

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