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Method to avoid the structural interference of the thrust system of a shield tunneling machine

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Science China(Technological Sciences) 2017年第5期60卷 701-712页

作者： WANG LinTao SUN Wei GONG GuoFang YANG huayong School of Mechanical Engineering Dalian University of Technology State Key Laboratory of Fluid Power Transmission and Control Zhejiang University

Several malfunctions of the shield tunneling machine （STM） caused by structural interference have been encountered in actual tunnel excavation. This paper is focusing on providing an effective method to avoid the structural interference based on making the reachable and the required workspaces of the thrust system match each other. The main structure of the thrust mechanism is analyzed, and coordinate systems are built up to describe the pose and workspace of the thrust mechanism. Constraint conditions are derived and the formulation of each constraint condition is carried out to facilitate the analysis of the reachable workspace of the thrust mechanism. Meanwhile, a reachable workspace determination algorithm is introduced based on interval analysis method. The mathematical model for determining the required workspace of the thrust mechanism is presented based on the analysis of the process when the STM excavates along a specific tunnel axis. Two applications are included to show how to avoid these problems by choosing reasonable parameters of the designed tunnel axis and the key structural parameters of the thrust mechanism based on workspace matching.

关键词： shield tunneling machine thrust system specific tunnel axis reachable workspace

Water-Assisted Injection Molding System Based on Water Hydraulic Proportional Control Technique

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Chinese Journal of Mechanical Engineering 2010年第4期23卷 418-427页

作者： ZHOU Hua ZHANG Zengmeng GAO Yuan＇an YANG huayong The State Key Lab of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China Jiujiang Branch of 707 Research Institute China Shipbuilding Industry Corporation Jiujiang 332007 China

Water-assisted injection molding（WAIM）, an innovative process to mold plastic parts with hollow sections, is characterized with intermittent, periodic process and large pressure and flow rate variation. Energy savings and injection pressure control can not be .attained based on conventional valve control system. Moreover, the injection water can not be supplied directly by water hydraulic proportional control system. Poor efficiency and control performance are presented by current trial systems, which pressurize injection water by compressed air. In this paper, a novel water hydraulic system is developed applying an accumulator for energy saving. And a new differential pressure control method is proposed by using pressure cylinder and water hydraulic proportional pressure relief valve for back pressure control. Aiming at design of linear controller for injection water pressure regulation, a linear load model is approximately built through computational fluid dynamics（CFD） simulation on two-phase flow cavity filling process with variable temperature and viscosity, and a linear model of pressure control system is built with the load model and linearization of water hydraulic components. According to the simulation, model based feedback is brought forward to compensate the pressure decrease during accumulator discharge and eliminate the derivative element of the system. Meanwhile, the steady-state error can be reduced and the capacity of resisting disturbance can be enhanced, by closed-loop control of load pressure with integral compensation. Through the developed experimental system in the State Key Lab of Fluid Power Transmission and Control, Zhejiang University, China, the static characteristic of the water hydraulic proportional relief valve was tested and output pressure control of the system in Acrylonitrile Butadiene Styrene（ABS） parts molding experiments was also studied. The experiment results show that the dead band and hysteresis of the water hydraulic propo

关键词： water-assisted injection molding water hydraulics proportional pressure control linear control load characteristic

A Nekhoroshev Type Theorem for the Nonlinear Wave Equation in Gevrey Space

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Chinese Annals of Mathematics,Series B 2019年第3期40卷 389-410页

作者： Chunyong LIU huayong LIU Rong ZHAO School of Mathematical Sciences Dalian University of Technology Shangdong Chemical Engineering & Vocational College Dalian Airforce Communication Non-Commissioned Officer Academy

In this paper, the authors prove a Nekhoroshev type theorem for the nonlinear wave equation u_(tt)=u_(xx)-mu-f(u),x∈[0, π] in Gevrey space.

关键词： Gevrey space Nonlinear wave equation Normal form Stability

铁轴草化学成分及其对HT-22细胞铁死亡抑制活性研究

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中草药 2024年第1期55卷 30-37页

作者：王欢刘翰飞舒晓蝶李金玉娄华勇潘卫东贵州医科大学省部共建药用植物功效与利用国家重点实验室贵州贵阳550014 贵州省天然产物研究中心贵州贵阳550014 贵州医科大学药学院贵州贵阳550025

目的研究铁轴草Teucrium quadrifarium化学成分及其生物活性。方法采用硅胶柱色谱、Sephadex LH-20柱色谱、半制备高效液相色谱以及重结晶等方法对铁轴草乙醇提取物的石油醚部位进行了系统分离纯化,并利用现代波谱技术对分离得到的单体... 详细信息

目的研究铁轴草Teucrium quadrifarium化学成分及其生物活性。方法采用硅胶柱色谱、Sephadex LH-20柱色谱、半制备高效液相色谱以及重结晶等方法对铁轴草乙醇提取物的石油醚部位进行了系统分离纯化,并利用现代波谱技术对分离得到的单体化合物进行结构鉴定;采用MTT法评估单体化合物对RSL3诱导的HT-22细胞铁死亡抑制活性。结果从铁轴草石油醚部位共分离得到16个化合物,分别鉴定为(4R,5S,7R)-木萝烷-1(6),10(14)-二烯-4,5-二醇(1)、对甲磺酰甲基苯酚(2)、合欢金素(3)、6,4′-二甲氧基-野黄芩苷(4)、香叶木素(5)、去甲氧基矢车菊黄酮素(6)、5-羟基-3,3′,4′,5′,7-五甲氧基黄酮(7)、蓟黄素(8)、吲哚-3-甲酸乙酯(9)、13-酮-9,11-十八碳二烯酸(10)、9-酮-10,12-十八碳二烯酸(11)、α-托可醌(12)、N-苯甲酰-L-苯丙氨酰-N-苯甲酰-L-苯丙氨酸酯(13)、金色酰胺醇酯(14)、2″,3″-乙酰马蒂罗苷(15)、香草醛(16)。活性筛选结果显示化合物7、9可以抑制铁死亡诱导剂RSL3诱导的HT-22细胞铁死亡,半数效应浓度(median effect concentration,EC50)分别为(1.46±0.49)μmol/L和(3.31±1.66)μmol/L。结论化合物1是新的倍半萜类化合物,命名为铁轴草素A;化合物2、4、6、7、9~16为首次从该属植物中分离得到。该研究结果为深入开发利用该植物提供一定的科学依据。

关键词：铁轴草香科科属铁死亡抑制活性铁轴草素A 5-羟基-3 3′ 4′ 5′ 7-5甲氧基黄酮吲哚-3-甲酸乙酯

Advances in Isotope Geochronology and Isotope Geochemistry:A Preface

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Journal of Earth Science 2022年第1期33卷 1-4页

作者： Xiangkun Zhu Zaicong Wang huayong Chen MLR Key Laboratory of Isotope Geology Institute of Geology Chinese Academy of Geological Sciences State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences China University of Geosciences Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of Geochemistry Chinese Academy of Sciences

Isotope geochronology and isotope geochemistry are important branches of geochemistry. They are based on variations in radiogenic or stable isotope ratios of elements and provide key chemical fingerprints to understand dynamic evolution of the Earth and other planetary bodies from the past to the present, and from their interior to exterior systems.

关键词： isotope geochemistry planetary

ROBUST CONTROL OF AN ELECTROHYDRAULIC PROPORTIONAL SPEED CONTROL SYSTEM WITH A SINGLEROD HYDRAULIC ACTUATOR

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Chinese Journal of Mechanical Engineering 2005年第4期18卷 597-602页

作者： Yang Jian Xu Bing Yang huayong College of Urban Railway Transportation Shanghai University of Engineering Science Shanghai 201600 China State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

A robust control algorithm is proposed to focus on the non-linearity and parameters＇ uncertainties of an electro-hydraulic proportional speed control system （EHPSCS） with a single-rod hydraulic actuator. The robust controller proposed does not need to design stable compensator in advance, is simple in design and has large scope of uncertainty applications. The feedback gains of the robust controller proposed are small, so it is easily implemented in engineering applications. Experimental research on the speed control under the different conditions is carried out for an EHPSCS. Experimental results show that the robust controller proposed has better robustness subject to parametric uncertainties, and adaptability of parameters＇ variation of control system itself and plant parameter variation.

关键词： Electro-hydraulic proportional speed control system (EHPSCS) Robust control Robustness

Investigation on structural optimization of anti-overturning slipper of axial piston pump

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Science China(Technological Sciences) 2012年第11期55卷 3010-3018页

作者： XU Bing ZHANG JunHui YANG huayong State Key Laboratory of Fluid Power Transmission and Control Zhejiang UniversityHangzhou 310027China

Improving the carrying ability of oil film between slipper and swash plate and reducing the partial abrasion of slipper are important to improve the service life and reliability of axial piston *** this paper,a numerical simulation model was developed for slipper/swash-plate friction pair based on the elastohydrodynamic *** dynamic micro-motion and pressure distribution of slipper were analyzed and it was pointed out that the tilt of slipper was the main reason for its partial *** simulations about the slippers with different slopes on the outer edge of the sealing belt showed that the partial abrasion could reduce the carrying ability and increase the leakage of the slipper/swash-plate *** proper slope on the inner edge helped to improve the carrying ability and reduce the leakage of *** experimental tests were in accord with the simulation results to a great extent,showing that the simulation model had a high accuracy and could be applied to the design and optimization of slipper,and that the slipper with optimal inner slope provided an encouraging method to improve the efficiency and reliability of axial piston pump.

关键词： axial piston pump slipper anti-overturning partial abrasion

Investigation on the Radial Micro-motion about Piston of Axial Piston Pump

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Chinese Journal of Mechanical Engineering 2013年第2期26卷 325-333页

作者： XU Bing ZHANG Junhui YANG huayong ZHANG Bin State Key Laboratory of Fluid Power Transmission and Control Zhejiang University

The limit working parameters and service life of axial piston pump are determined by the carrying ability and lubrication characteristic of its key friction pairs. Therefore, the design and optimization of the key friction pairs are always a key and difficult problem in the research on axial piston pump. In the traditional research on piston/cylinder pair, the assembly relationship of piston and cylinder bore is simplified into ideal cylindrical pair, which can not be used to analyze the influences of radial micro-motion of piston on the distribution characteristics of oil-film thickness and pressure in details. In this paper, based on the lubrication theory of the oil film, a numerical simulation model is built, taking the influences of roughness, elastic deformation of piston and pressure-viscosity effect into consideration. With the simulation model, the dynamic characteristics of the radial micro-motion and pressure distribution are analyzed, and the relationships between radial micro-motion and carrying ability, lubrication condition, and abrasion are discussed. Furthermore, a model pump for pressure distribution measurement of oil film between piston and cylinder bore is designed. The comparison of simulation and experimental results of pressure distribution shows that the simulation model has high accuracy. The experiment and simulation results demonstrate that the pressure distribution has peak values that are much higher than the boundary pressure in the piston chamber due to the radial micro-motion, and the abrasion of piston takes place mainly on the hand close to piston ball. In addition, improvement of manufacturing roundness and straightness of piston and cylinder bore is helpful to improve the carrying ability of piston/cylinder pair. The proposed research provides references for designing piston/cylinder pair, and helps to prolong the service life of axial piston pump.

关键词： axial piston pump piston/cylinder pair micro motion carrying ability

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遵义方言语气词“吔”的提醒及反预期功能

语言研究集刊

语言研究集刊 2024年第1期33卷 205-223,M0009,M0010页

作者：罗虞欢林华勇中山大学中文系广州510275

遵义方言的语气词“吔[ie]”可在陈述句的句中做主位标记,在陈述句的句末标记反预期及提醒相关事实,疑问句句末提醒疑问点,祈使句句末提请考虑请求,核心功能可概括为“提醒”。“吔”有[31]、[33]、[55]三个调,在同一句类的句末都存在... 详细信息

遵义方言的语气词“吔[ie]”可在陈述句的句中做主位标记,在陈述句的句末标记反预期及提醒相关事实,疑问句句末提醒疑问点,祈使句句末提请考虑请求,核心功能可概括为“提醒”。“吔”有[31]、[33]、[55]三个调,在同一句类的句末都存在两个调,调越高,越容易引起对方的注意,这一点具有普遍性。“吔”与普通话的“呢”在陈述句句中和疑问句句末的表现基本一致,在陈述句句末,只有语境为反预期时才能对译。在自然口语语料的基础上进行测试式描写,能够更全面细致地展现语气词的句法语义特点。

关键词：西南官话语气词反预期提醒