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Kinematics and Path Following Control of an Articulated Drum Roller

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Chinese Journal of Mechanical Engineering 2017年第4期30卷 888-899页

作者： Yongming BIAN Meng YANG Xiaojun FANG xiahui wang School of Mechanical Engineering Tongji UniversityShanghai 201804China

Automatic navigation of an articulated drum roller, which is an articulated steering type vehicle widely used in the construction industry, is highly expected for operation cost reduction and improvement of work effi- ciency. In order to achieve the path following control, considering that its steering system is articulated steering and two frames are articulated by an active revolute joint, a kinematic model and an error dynamic state-space equation of an articulated drum roller are proposed. Besides, a state- feedback control law based on Lyapunov stability theory is also designed, which can be proved to achieve the purpose of control by the analysis of stability. What＇s more, to evaluate the performance of the proposed method, simu- lation under the MATLAB/Simulink and experiments using positioning algorithm and errors correction at the uneven construction site are performed, with initial dis- placement error （-1.5 m）, heading error （-0.11 tad） and steering angle （-0.19 rad）. Finally, simulation and exper- imental results show that the errors and steering angle can decrease gradually, and converge to zero with time. Meanwhile, the control input is not saturated. An articu- lated drum roller can lock into a desired path with the proposed method in uneven fields.

关键词： Kinematics Path following controlArticulated drum roller Positioning algorithmPositioning errors correction

The Nature-Based Ecological Engineering Paradigm: Symbiosis, Coupling, and Coordination

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Engineering 2022年第12期19卷 14-21页

作者： xiahui wang Jinnan wang Bo wang Benjamin Burkhard Lulu Che Chao Dai Lijie Zheng Institute of Ecological Conservation and Restoration Chinese Academy of Environmental PlanningBeijing 100012China Joint Laboratory of Ecological Products and Natural Capital Beijing 100012China Center of Biodiversity and Nature Reserves Chinese Academy of Environmental PlanningBeijing 100012China Institute of Physical Geography and Landscape Ecology Leibniz University HannoverHannover LS 30167Germany

*** We are currently facing three major ecological threats on a global scale:biodiversity loss,climate change,and environmental pollution *** degradation of terrestrial and marine ecosystems poses a major risk to human survival and development,brings serious impacts to the wellbeing of 3.2 billion people,and causes the loss of about 10%of the annual global gross domestic product(GDP)[1,2].Meanwhile,the coronavirus disease 2019(COVID-19)epidemic is still spreading rapidly throughout the world,showing that the present relationship between humans and nature is *** is necessary to protect nature so as to maintain the self-resilience of ecosystems.

关键词： Ecological ecosystems maintain

Thoughts and Practice of Ecological Protection and Restoration of Mountains, Rivers, Forests, Farmlands, Lakes and Grasslands

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Journal of Landscape Research 2020年第3期12卷 5-8页

作者： wang xiahui HE Jun wang Bo ZHANG Xiao Chinese Academy of Environmental Planning Beijing 100012China

The report of the 19th National Congress of the Communist Party of China stated that it was necessary to establish and practice the concept that lucid waters and lush mountains are invaluable assets,treat the ecological environment as life,and coordinate the management of mountains,rivers,forests,farmlands,lakes and *** recent years,China has organized a series of pilot projects for the ecological protection and restoration of mountains,rivers,forests,farmlands,lakes and grasslands,breaking the boundary between administrative divisions,departmental management and ecological elements,and implementing conservation and restoration oriented towards the improvement of ecosystem services,so as to solve the problem of the lack of overall planning for ecological protection and restoration projects and the separated management of ecological *** study systematically elaborated the theoretical basis and connotation characteristics of ecological protection and restoration of mountains,rivers,forests,farmlands,lakes and *** proposed the implementation path of ecological protection and restoration project of mountains,rivers,forests,farmlands,lakes and grasslands by taking the water source conservation area of Beijing-Tianjin-Hebei as a case,so as to provide reference for the implementation and decision-making management of ecological protection and restoration projects in various regions.

关键词： Mountains rivers forests farmlands lakes and grasslands Ecological protection and restoration Ecological service functions Ecological elements

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论职业资格考试对高职教育的反拨作用

教育与职业 2010年第23期 19-20页

作者：王霞晖江苏食品职业技术学院外语系

文章根据测试学中的＂反拨作用＂原理,分析职业资格考试对高职教育的教学目标、课程设置、教学模式和学生的学习动机、学习态度、学习能力的正面和负面作用。文章指出要理性地对待职业资格考试,建立立体多元化评价体系,以工学结合设置课... 详细信息

文章根据测试学中的＂反拨作用＂原理,分析职业资格考试对高职教育的教学目标、课程设置、教学模式和学生的学习动机、学习态度、学习能力的正面和负面作用。文章指出要理性地对待职业资格考试,建立立体多元化评价体系,以工学结合设置课程,使学业考试与职业资格考试对等,学生在掌握岗位技能的同时也要具备必需的职业素质。

关键词：职业资格考试反拨作用高职教育职业岗位群

基于SPOC平台的现代学徒制“订制”课程建设

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职业技术教育 2018年第23期39卷 23-26页

作者：王霞晖江苏食品药品职业技术学院教务处

课程建设是人才培养的主要要素之一,课程建设是推动现代学徒制实施的重要内容和关键。在"互联网+"的大背景下,按照"理实逆向"原则,重构适合职业能力培养的课程体系;根据学徒制"订制"课程特征,编制课程建设标准并形成建设指标体系;利用... 详细信息

课程建设是人才培养的主要要素之一,课程建设是推动现代学徒制实施的重要内容和关键。在"互联网+"的大背景下,按照"理实逆向"原则,重构适合职业能力培养的课程体系;根据学徒制"订制"课程特征,编制课程建设标准并形成建设指标体系;利用互联网平台,实施教学运行和质量监控,满足了现代学徒制育人模式的需求。

关键词：现代学徒制课程建设 SPOC平台订制

环境DNA在监测表层沉积物中的运用及其与环境变量的关系

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环境工程学报 2020年第8期14卷 2262-2269页

作者：魏楠王夏晖张春鹏生态环境部环境规划院北京100012 东京大学都市工学系日本东京113-8656 吉林大学地下水资源与环境教育部重点实验室长春130021

环境DNA技术是近几年出现的新兴环境生态监测技术,为研究环境变量对表层沉积物中环境DNA变化的影响,通过小试实验模拟海水环境并以日本大螯蜚作为目标生物,引入4组不同的生物丰度,运用环境DNA技术研究了表层沉积物中环境DNA含量变化与... 详细信息

环境DNA技术是近几年出现的新兴环境生态监测技术,为研究环境变量对表层沉积物中环境DNA变化的影响,通过小试实验模拟海水环境并以日本大螯蜚作为目标生物,引入4组不同的生物丰度,运用环境DNA技术研究了表层沉积物中环境DNA含量变化与周边环境变量的关系。在小试装置中养殖日本大螯蜚4 d后全部取出,之后启动实验。在实验启动后的第0、6、12、18、24、72、144、264、384小时进行取样,提取出的环境DNA片段含量通过实时荧光进行定量PCR检测。结果表明,表层沉积物中的环境DNA在源生物移除后72 h内降低至较低含量水平,与水体中的环境DNA有较为相似的变化特征。通过广义线性回归分析,发现环境DNA降解速率与水质盐度呈显著负相关(P=0.0005),与pH呈显著正相关(P=0.04),说明表层沉积物中的环境DNA对于周边环境变化具有一定指示意义。上述结果为进一步推动环境DNA技术的应用及其对环境变量影响作用的深入研究提供参考。

关键词：环境生物监测环境DNA 表层沉积物环境变量底栖生物

农业流域“汇”型景观结构对径流调控及磷污染物截留作用的研究

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环境科学学报 2005年第3期25卷 293-299页

作者：王夏晖尹澄清单保庆中国科学院生态环境研究中心环境水质学国家重点实验室

选取天津于桥水库北岸桃花寺流域作为实验流域 ,进行了流域景观格局对生态水文及磷污染物迁移转化过程影响的野外实验研究 .研究结果表明 ,流域中广泛分布于季节性河流附近的汇型景观结构 (石坝、植草水道、植被过滤带、干塘、缓冲区等 ... 详细信息

选取天津于桥水库北岸桃花寺流域作为实验流域 ,进行了流域景观格局对生态水文及磷污染物迁移转化过程影响的野外实验研究 .研究结果表明 ,流域中广泛分布于季节性河流附近的汇型景观结构 (石坝、植草水道、植被过滤带、干塘、缓冲区等 ) ,通过滞留 /缓冲功能 ,对地表径流的流速及流量具有双重调控作用 ,延长了养分物质在流域内部的滞留时间 ,对产生于不同源区的面源污染径流具有截留、吸纳、贮存作用 ,使径流中泥沙和磷素浓度逐渐得到降低 ,减少了养分对下游水体的负荷输出 .多次降雨径流的监测结果表明 ,无论在大暴雨下的连续流事件还是在小雨下的间断流事件中 ,汇型景观结构均能表现出良好的养分持留功能 .在 2 0 0 3年 6月 2 2日连续径流事件中 ,地表径流的流速可由系统入口处的 3 7 2cm·s- 1 降至系统出口处的 11 1cm·s- 1 ,污染径流体积可削减 5 0 2 % ,TSS、TP、TDP、DRP的持留率分别可达 72 7% ,69 3 % ,5 9 8%和 5 7 9% .在间断径流事件中 ,污染径流全部为汇型景观结构所截留 ,泥沙和磷素的持留率更高 .对 2 1场降雨径流事件的统计分析结果表明。

关键词：径流调控磷污染物截留作用面源污染水质景观结构污染物农业