农业机械自主导航技术一直是现代农业发展的关键技术,而已有的机器视觉导航中普遍存在鲁棒性不强、适应性弱等缺点.针对上述问题,提出基于卷积神经网络的田间路径导航算法.根据主流语义分割模型FCNVGG16得到改进分割网络FCNVGG14,用于田间作物行分割任务的预处理,再通过非监督点聚类法进行特征点分类,最后采用改进后的Hough变换(PKPHT)拟合出导航直线.分析结果表明:与U-Net等主流算法相比,基于FCNVGG14网络模型的图像分割算法,IOU(交并比)指标在多通道输入时提升2％,在单通道输入时IOU指标提升4％,取得良好的分割效果.对分割网络FCNVGG14改进相对于传统的图像阈值分割算法,克服作物缺失、田间杂草过多、光照不均等自身缺陷导致的直线拟合时不可避免出现误检测、偏差大等问题.经田间路径导航试验证明,在田间照度符合人眼的情况下,基于FCNVGG16的改进模型路径识别算法检测准确率不低于92％,单帧检测时间在100 ms以内,在作业平台的速度不大于0.5 m/s条件下,最大横向偏差为9.84 cm、平均偏差不超过6.68 cm,说明用于机器视觉导航可行,这为低算力田间视觉导航提供新的方法和思路.

2020年中国脱贫攻坚任务如期全面完成,如何巩固拓展脱贫攻坚成果成为后扶贫时代理论与实践关注的重要话题.各地在实践过程中探索出一系列巩固拓展脱贫攻坚成果与高质量脱贫的创新做法与高效举措.基于全国32省117个扶贫案例,采用文本挖掘法提炼出能够表征各地实践行为要素的案例关键词,并通过分析关键词外部特征反映出各地政府在脱贫攻坚进程中的共性关切与政策聚焦.在此基础上利用扎根理论的方法对各行为要素进行进一步的归纳提升,构建出以落实防贫保障为基础、夯实发展基础为前提、构建长效机制为关键、强化志智双扶为根本、推进产业升级为重心、衔接乡村振兴为目标的"六位一体"的巩固拓展扶贫成果路径.

实现巩固拓展脱贫攻坚成果同乡村振兴有效衔接,不仅是社会主义现代化国家建设进程中的必然选择,也是解决当前中国社会主要矛盾的现实需要.在政策衔接过程中,由于脱贫攻坚与乡村振兴发展目标与定位的不同,二者的衔接呈现出多重差异,既有制度衔接本身的差异,亦有因为定位不同而造成的差异;同时当前衔接过程缺乏对"有效性"的指标量化,致使难以准确度量和表达有效衔接的程度.为此,本文通过凝练抽象出"住差"与"效度"概念以应用性解构"有效衔接","位差"即发展进程的时间位差、区域发展的空间位差、发展力量的角色位差;"效度"指时间维度上政策衔接及时不脱节,经济维度上资源配置科学不浪费,需求维度上举措公平不遗漏,即实现效率角度的及时性、效益角度的节约性、效果角度的公平性.在此基础上,通过弥合位差、提升效度构建出包括宏观制定包容性公共政策、中观提升产业与劳动力市场益贫性和微观建设主体的能力的三维框架,着力细化面向社会大众普惠性的基本公共服务政策、优化面向脆弱群体特惠性的兜底性保护政策、深化以效率为导向兼顾公平的社会市场政策,以期为实现巩固拓展脱贫攻坚成果同乡村振兴有效衔接提供优化路径与有益镜鉴.

当前脱贫攻坚战的目标是到2020年实现中国现行标准下农村贫困人口全部脱贫,这一标准属于与基本需求相联系的绝对贫困标准.2020年后的中国贫困总体上表现为相对贫困,即收入显著低于社会平均收入与中位数收入的低收入贫困,但也有其他表现形式的贫困:如以"困"为显著特征的特殊群体贫困、刚性支出或不合理支出过量的支出性贫困、城乡二元结构影响下的城乡流动性贫困、受风险冲击产生的暂时性贫困,以及区域不平衡的发展型贫困等.作为一个发展中的大国,中国贫困的产生既有发展不充分的原因,亦有发展不平衡的症结,甚至兼而有之.基于此,反贫困的公共政策应遵循加强能力建设、发展社会市场经济、完善公共服务、加强社会保护等路径,从而为贫困人口提供更多的基础福利覆盖、发展条件和环境、就业机会、风险防范和兜底保障等.

脱贫攻坚期间,中国政府及时提出坚持开发式扶贫与保障性扶贫相统筹的要求,社会保障减贫政策的成功实践不仅为消除绝对贫困奠定兜底性保障,也为未来社会保障减贫的制度化发展提出新命题.在回溯社会保障理论发展沿革的基础上,系统梳理以美国、欧盟和韩国为代表的发达国家(地区)与以印度、巴西为代表的发展中国家(地区)社会保障减贫政策,通过政策比较分析归纳出社会救助、社会保险、就业政策和基础社会福利在消除相对贫困中的重要作用.基于此,提出社会保险遏制贫困增量、社会救助减少贫困存量、积极劳动市场项目控制贫困变量的反贫困政策框架,中国未来的贫困治理应以农民工等群体为中心、人力资本建设为重心,坚持开发式扶贫和保障性扶贫相统筹.

This paper focuses on the fuzzy obstacle avoidance algorithm, which is based on the information in dynamic environment with high real-time performance and adaptability. The algorithm can convert the information acquired in three directions through the ultrasonic sensors into fuzzy variables and input into the fuzzy controller, and realize the robot obstacle avoidance according to the inference rules. In order to solve the calculation problem of fuzzy inference rules, a fuzzy inference algorithm based on the addressing is presented to save computing time.

The electrical automation equipments has been developed for decades.The speed of development in China has been also accelerated continuously.The application of microcontrollers in the automation equipments is very broad,but the price of microcontrollers is high,which gives a great limitation for the development of microcontrollers in Chinese market.The microcontroller design in equipment automation usually goes through the process of scheme design to achieve the purpose of saving the material and reducing its cost.The equipment automation renovation is to analyze and research such problems.

With the rapid development of economy and the increase of scientific and technological level,intelligence data collection system is widely used in the industrial production and scientific studies.In the information age,data and information had become the important resource and data collection system further promotes the man-machine interaction and automatic detection control of the device,providing convenience for the modern industrial production.This article examines necessity of the research on intelligence data collection system based on SCM,and expounds the key points of design and the methods,to contribute to the reform and innovation of intelligent data collection system based on SCM.

本文采用了PXI以及LabVIEW可视化编程软件设计了一套具有模块化、通用化、系列化的电机转子实验系统,具有数据采集、数据测量、数据存储、数据共享和数据分析处理功能够快速有效地反映出被测系统的各种参数信息,便于对被测对象进行状态监测与故障诊断。

The nose bridge between the inlet valve and exhaust valve is the most fragile part on the cylinder head. Fatigue crack is the major failure mode. It is necessary to analyze the structure strength and reliability (SSR) of this zone. In this paper, a three-dimensional (3D) model for a engine cylinder head is built up using Pro/Engineer wildfire 2.0, and the 3D FEM analysis of the SSR is carried out. The temperature field and stress field of the nose bridge are also calculated based on the model. Several improvement designs are given and compared as the result of the above analysis, which lays the foundation for the cylinder head production.

We design a test system based on virtual instrument to acquire input signal from agricultural machine sensors. The software of the test system is based on LabWindows/CVI, which is a software platform on test and control. This test system can also test static and dynamic characteristics of force sensors. The test results are satisfying. Compared with traditional test system, the system has friendly software interface and is convenient to use.

This paper designed a virtual test system on vehicle handling and stability,established the dynamic model for handling and stability.The virtual proving ground was made of hierarchical components and constructed by a serious of special classes.Light,fog and voice was set to the proving ground also.The virtual test process is the vehicle model driven in the virtual proving ground by the vehicle parameters and states obtained from the dynamics simulation,and is realized by the World Tool Kit(WTK) software.Stereovision images are reached by splitting the display window.The actual test shows that when the vehicle model runs in the virtual ground,driver can obtain the partly reality felling,and the virtual test is closed to the real test.This study delivered a new approach of quick investigation,evaluation for innovative concepts in automotive development which can drastically reduce the time and cost.

分析了镍氢电池充电管理系统的设计需求,提出了一种采用电压、温度和时间进行综合控制的充电管理方案.设计了基于ATmega8的新型柔性充电系统,同时给出了该系统的软硬件设计方法.

There are many kinds of motors used in electronic vehicle(EV), such as the DC motor, the induction motor, the permanent magnet motor and switched reluctance motor, and here the four motor control systems will be compared. The paper briefly introduces the vector control theory of permanent magnet synchronous motors (PMSM) and presents a new method of PMSM control system based on MCU (Micro Control Unit) Infineon 16 bit XC164CM, which is the latest product of Infineon Technology for vehicle electronic area, especially for motor control. The SVPWM (Space Vector Pulse-Width Modulation) technology is discussed used in PMSM control system, and the advantages of PMSM control system are being taken more and more attention. Here the hardware design and software programming are introduced. The control system based on Infineon XC164CM brings a new digitized realization of Vector Control Project for PMSM. This chip has powerful PWM generator, separate timer, dead timer generator and block control model, so the control system can realize frequency control easily. The control system based on Infineon XC164CM for PMSM has high efficiency, high power factor and wide timing scope and it will be widely used.

嵌入式产品开发中的主回路一般使用+5V电源,但数据采集系统的运放一般要求±12V电源,而嵌入式系统常用的STN屏则要求提供随温度变化的其他不规则电源(如Optrex公司的液晶屏大部分需要-17V～-27V的显示驱动电压;Sharp公司的液晶屏大部分需要+17V～+27V的显示驱动电压).虽然这种电路对电流的需求不大,但电压种类多,是嵌入式系统电源设计的难点.利用本文介绍的MC34063芯片可以很容易的满足以上电源设计需求,从而实现升压、降压、反压和变压器初级线圈驱动等多种功能.

该文详细介绍了虚拟仪器的原理及编程体系,设计了用于车辆平顺性试验的数据采集系统、试验数据回放系统.首先,定义图形用户交互界面,设定试验中各种操作的控制按钮及图形数据显示窗口,生成* .uir文件.其次,使用LabWindows/CVI的程序编辑窗口,产生数据显示、数据加载、模拟仿真等执行程序文件.最后,将试验所获得的数据(以文本件形式保存)通过加载程序调用,实现了试验数据的再现,使试验数据的测试分析、结果显示由基于计算机的软件系统来完成.

介绍了振动管式液体密度计的工作原理,以及自行研制的悬臂梁式U型石英玻璃管式液体密度计的结构,采用集中参数法对其振动方程进行了推导,设计了信号采集与处理系统,并对整个测量系统进行了试验分析.结果表明,所设计的振动管式液体密度计工作稳定、测量精度高.通过误差分析发现,温度是造成测量误差的主要原因,文中推导了温度修正系数.

<span id="ChDivSummary" name="ChDivSummary" class="abstract-text">采用模糊控制理论和方法，研究驾驶员－汽车－环境闭环系统的操纵稳定性。建立了驾驶员智能模型，研制出整个闭环系统的仿真软件。对几种典型工况的汽车运行进行了模拟。试验结果证明闭环系统模型合理，仿真结果正确。</span>