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NEURO-FUZZY NETWORKS IN CAPP

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Chinese Journal of Mechanical Engineering 2000年第1期13卷 30-34页

作者： Bernard S Maiyo wang xiankui Lin Chengying (Department of Precision Instruments and Mechanology, Qinghua University) 清华大学北京

The neuro-fuzzy network (NFN) is used to model the rules and experience of the process planner. NFN is to select the manufacturing operations sequences for the part features. A detailed description of the NFN system development is given. The rule structure utilizes sigmoid functions to fuzzify the inputs, multiplication to combine the if Part of the rules and summation to integrate the fired rules. Expert knowledge from previous process Plans is used in determinning the initial network structure and parameters of the membership functions. A back-propagation (BP) training algorithm was developed to fine tune the knowledge to company standards using the input-output data from executions of previous plans. The method is illustrated by an industrial example.

关键词： Neuro-fuzzy networks Training Semi-generative systems CAPP

RESEARCH ON THE ON-LINE MEASURING SYSTEM FOR THE MIDDLE-CONVEX AND VARYING ELLIPSE PISTON SKIRT

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Chinese Journal of Mechanical Engineering 2001年第4期14卷 305-309页

作者： wang xiankui,Jiang Simin,Qian Lei,Shi Zhongdong,Wu Dan (Department of the Precision Instrument and Mechanics,Qinghua University) 清华大学北京

The middle convex and varying ellipse piston is th e key component of an internal combustion engine In general,the piston is mac hined by non circular section CNC lathe,but the measuring of piston profile is manipulated by off line Because the off line measuring reference is differen t from the machining reference,the measurement result is diverse from the act ual dimension A new method to measure the middle convex and varying ellipse p iston profile, which is known as on line measuring, is presented By using thi s kind of method,the high measurement accuracy can be gained,as well as meeting the production requirement.

关键词： Middle-convex and varying ellipse piston On -line measure Non circular section

Degree of shade tolerance shapes seasonality of chlorophyll, nitrogen and phosphorus levels of trees and herbs in a temperate deciduous forest

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Journal of Forestry Research 2024年第4期35卷 60-72页

作者： Jiajia Zeng Fan Liu Yuan Zhu Jiayi Li Ying Ruan xiankui Quan Chuankuan wang Xingchang wang Aulin College Northeast Forestry UniversityHarbin 150040People’s Republic of China Center for Ecological Research Northeast Forestry UniversityHarbin 150040People’s Republic of China Key Laboratory of Agricultural Water Resources Center for Agricultural Resources ResearchInstitute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021People’s Republic of China Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016People’s Republic of China Key Laboratory of Sustainable Forest Ecosystem Management Ministry of EducationNortheast Forestry UniversityHarbin 150040People’s Republic of China

Forest productivity is closely linked to seasonal variations and vertical differentiation in leaf ***,leaf structural and chemical traits variation among co-existing species,and plant functional types within the canopy are poorly *** this study,the seasonality of leaf chlorophyll,nitrogen(N),and phosphorus(P)were quantified vertically along the canopy of four major tree species and two types of herbs in a temperate deciduous *** role of shade tolerance in shaping the seasonal variation and vertical differentiation was *** the entire season,chlorophyll content showed a distinct asymmetric unimodal pattern for all species,with greater chlorophyll levels in autumn than in spring,and the timing of peak chlorophyll per leaf area gradually decreased as shade tolerance *** a:b ratios gradually decreased with increasing shade *** N and P contents sharply declined during leaf expansion,remained steady in the mature stage and decreased again during leaf *** the seasons,the lower canopy layer had significantly higher chlorophyll per leaf mass but not chlorophyll per leaf area than the upper canopy layer regardless of degree of shade ***,N and P per leaf area of intermediate shade-tolerant and fully shade-tolerant tree species were significantly higher in the upper canopy than in the *** variations in N:P ratios suggest changes in N or P *** findings indicate that shade tolerance is a key feature shaping inter-specific differences in leaf chlorophyll,N,and P contents as well as their seasonality in temperate deciduous forests,which have significant implications for modeling leaf photosynthesis and ecosystem production.

关键词： Leaf traits Leaf nutrients Seasonal variations Chlorophyll Nitrogen Phosphorus Shade tolerance Canopy layers

Protein post-translational modifications in auxin signaling

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Journal of Genetics and Genomics 2024年第3期51卷 279-291页

作者： xiankui Cui Junxia wang Ke Li Bingsheng Lv Bingkai Hou Zhaojun Ding The Key Laboratory of Plant Development and Environmental Adaptation Biology Ministry of EducationSchool of Life SciencesShandong UniversityQingdaoShandong 266237China Shandong Academy of Grape JinanShandong 250100China College of Horticulture Qingdao Agricultural UniversityQingdaoShandong 266109China

Protein post-translational modifications(PTMs),such as ubiquitination,phosphorylation,and small ubiquitin-like modifier(SUMO)ylation,are crucial for regulating protein stability,activity,subcellular localization,and binding with *** modifications remarkably increase the variety and complexity of proteomes,which are essential for regulating numerous cellular and physiological *** regulation of auxin signaling is finely tuned in time and space to guide various plant growth and *** evidence indicates that PTMs play critical roles in auxin signaling ***,a thorough and systematic review of the functions of PTMs in auxin signal transduction will improve our profound comprehension of the regulation mechanism of auxin signaling and auxin-mediated various *** review discusses the progress of protein ubiquitination,phosphorylation,histone acetylation and methylation,SUMOylation,and S-nitrosylation in the regulation of auxin signaling.

关键词： Arabidopsis thaliana Auxin Auxin signaling Post-translational modifications Protein regulation

基于扰动观测的非圆零件CNC加工的迭代学习复合PID控制

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机械工程学报 2014年第17期50卷 179-185页

作者：江思敏王先逵娃哈哈集团研究院机电研究所杭州310018 清华大学精密仪器系北京100084

在加工高精度非圆零件时,通常先产生非圆零件的轮廓生成直线伺服器的运动轨迹,然后高响应直线伺服器按照生成的运动轨迹进行往复运动,并和驱动非圆零件的主轴同步控制。非圆零件加工轨迹的控制精度是影响零件数控加工的重要因素。提出... 详细信息

在加工高精度非圆零件时,通常先产生非圆零件的轮廓生成直线伺服器的运动轨迹,然后高响应直线伺服器按照生成的运动轨迹进行往复运动,并和驱动非圆零件的主轴同步控制。非圆零件加工轨迹的控制精度是影响零件数控加工的重要因素。提出一种基于扰动观测的数字PID和迭代学习复合控制算法,根据非圆轮廓轨迹表现的周期性特征,使用数字PID和迭代学习控制的方法,可以有效达到非圆零件加工的控制精度,加工过程中的扰动同样影响零件的加工精度,通过扰动观测器来实现对扰动的有效反馈补偿控制,提高系统的控制精度,从而使非圆截面的切削控制精度得到提高,非圆零件的加工精度也可以得到显著提高。

关键词：迭代学习数字PID控制扰动观测器非圆切削高速响应直线伺服器

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面向刀具优选的权重决策

清华大学学报（自然科学版） 1998年第2期38卷 69-71页

作者：吴丹王先逵清华大学精密仪器与机械学系

在计算机辅助工艺过程设计（ＣＡＰＰ）中，刀具选择是一个复杂的优化过程，它受到多种因素的影响。文中采用多因素评价的方法，建立了刀具优选模型，并用权重值表示各因素的相对重要性。运用层次分析法确定各因素的权重，用“专家”知... 详细信息

在计算机辅助工艺过程设计（ＣＡＰＰ）中，刀具选择是一个复杂的优化过程，它受到多种因素的影响。文中采用多因素评价的方法，建立了刀具优选模型，并用权重值表示各因素的相对重要性。运用层次分析法确定各因素的权重，用“专家”知识对其进行校验，并采用最小二乘学习算法调整权重。该权重决策方法用于智能化ＣＡＰＰ系统的选刀模块中，可以对影响刀具选择的各因素进行合理的权重分配，为几个典型非回转体零件选择合理的刀具。

关键词：刀具优选 CAPP 权重

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精密复合加工技术

现代制造工程 2012年第2期 1-6页

作者：王先逵清华大学精密仪器与机械学系制造工程研究所北京100081

首先阐述了复合加工技术的含义,提出广义复合加工技术的观点,特别是精密复合加工技术的概念。然后论述了精密复合加工技术在制造技术发展中的作用和创新意义,认为它是解决制造技术中工艺难题的重要手段,是在制造技术创新中求发展的新兴... 详细信息

首先阐述了复合加工技术的含义,提出广义复合加工技术的观点,特别是精密复合加工技术的概念。然后论述了精密复合加工技术在制造技术发展中的作用和创新意义,认为它是解决制造技术中工艺难题的重要手段,是在制造技术创新中求发展的新兴视野,是提升制造技术核心竞争力的有效途径。继而阐述了复合加工的类型,介绍了四种精密复合加工技术,即复合结合剂金刚石微粉砂轮超精密磨削技术、精密砂带振动磨削和研抛技术、精密车铣加工技术和化学机械抛光技术等,最后阐述了复合加工的应用和发展,以及当前应重视的问题。

关键词：精密复合加工作用叠加功能集合多件并行

基于最少拍无波纹的零相位误差跟踪控制在精密直线位移装置中的应用

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机械工程学报 2007年第5期43卷 111-115页

作者：颜菡王先逵段广洪清华大学精密仪器与机械学系北京100084

为使精密直线位移装置控制系统的输出响应能够准确而且快速地跟踪输入指令,同时消除由直接驱动带来的负载扰动、切削力波动等因素对系统性能造成的不利影响,针对用于非圆截面零件数控车削的精密直线位移系统,提出一种基于最少拍无波纹... 详细信息

为使精密直线位移装置控制系统的输出响应能够准确而且快速地跟踪输入指令,同时消除由直接驱动带来的负载扰动、切削力波动等因素对系统性能造成的不利影响,针对用于非圆截面零件数控车削的精密直线位移系统,提出一种基于最少拍无波纹控制的零相位误差跟踪控制(Zero phase error tracking control,ZPETC)方案。该方案既能消除不稳定零点导致的系统相位误差,又能提高系统的响应速度。仿真结果表明,基于最少拍无波纹控制的ZPETC方法,有效地改善系统的跟踪性能。系统对于正弦信号的稳态跟踪误差可以达到±0.5μm,其阶跃响应准确且速度快。与一般精密直线位移装置的控制方法相比,此方法能提高系统的跟踪精度,同时具有良好的抗干扰能力,具有广泛的应用前景。

关键词：精密直线位移装置最少拍无波纹控制零相位误差跟踪控制前馈控制

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快速刀具伺服机构研究进展

中国机械工程 2008年第11期19卷 1379-1385页

作者：吴丹谢晓丹王先逵清华大学北京100084

快速刀具伺服机构(FTS)是非圆数控车削和非轴对称车削的一项共同的关键性技术。论述了FTS的发展历程、结构特点及性能指标。详细介绍了压电陶瓷FTS、磁致伸缩FTS、洛仑兹力FTS、麦克斯韦力FTS的国内外研究情况,阐述了它们的原理、结构... 详细信息

快速刀具伺服机构(FTS)是非圆数控车削和非轴对称车削的一项共同的关键性技术。论述了FTS的发展历程、结构特点及性能指标。详细介绍了压电陶瓷FTS、磁致伸缩FTS、洛仑兹力FTS、麦克斯韦力FTS的国内外研究情况,阐述了它们的原理、结构、性能优缺点及应用情况,并给出了FTS用于非轴对称光学元件车削的实例。指出超高频响(大于1000Hz)短行程(小于100μm)的FTS是当今研究热点,压电陶瓷FTS和麦克斯韦力FTS都可以实现较高频响,其中麦克斯韦力型FTS是可实现超高频响的一种全新类型的FTS。

关键词：快速刀具伺服机构响应频率非圆车削非轴对称车削