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Atlas Based Kinematic Optimum Design of the Stewart Parallel Manipulator

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Chinese Journal of Mechanical Engineering 2015年第1期28卷 20-28页

作者： shao Zhufeng TANG Xiaoqiang WANG Liping SUN Dengfeng State Key Laboratory of Tribology Department of Mechanical EngineeringTsinghua University Beijing Key Lab of Precision/Ultra-precision Manufacturing Equipments and Control Tsinghua University School of Aeronautics and Astronautics Engineering Purdue University

Optimum design is a key approach to make full use of potential advantages of a parallel manipulator. The optimum design of multi-parameter parallel manipulators（more than three design parameters）, such as Stewart manipulator, relies on analysis based and algorithm based optimum design methods, which fall to be accurate or intuitive. To solve this problem and achieve both accurate and intuition, atlas based optimum design of a general Stewart parallel manipulator is established, with rational selection of design parameters. Based on the defined spherical usable workspace（SUW）, primary kinematic performance indices of the Stewart manipulator involving workspace and condition number are introduced and analyzed. Then, corresponding performance atlases are drawn with the established non-dimensional design space, and impact of joint distribution angles on the manipulator performance is analyzed and illustrated. At last, an example on atlas based optimum design of the Stewart manipulator is accomplished to illustrate the optimum design process, considering the end-effector posture. Deduced atlases can be flexibly applied to both quantitative and qualitative analysis to get the desired optimal design for the Stewart manipulator with respect to related performance requirements. Besides, the established optimum design method can be further applied to other multi-parameter parallel manipulators.

关键词： optimum design performance atlas parallel mechanism Stewart

Magnesium isotopes of chlorite-rich hydrothermal sediments in the Okinawa Trough and indications for Mg cycle

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Science China Earth Sciences 2023年第3期66卷 648-662页

作者： Hebin shao Shouye YANG Aiguo DONG Zhongya HU Key Laboratory for Polar Science of the State Oceanic Administration Polar Research Institute of ChinaShanghai 200136China State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China Institute of Earth Sciences China University of Geosciences(Beijing)Beijing 100083China

Seafloor hydrothermal systems play a significant role in the oceanic Mg cycle due to ubiquitous deposits of secondary Mg-rich clays during the strong fluid-rock ***,the magnitude of net Mg enrichment and Mg isotopic fractionation,particularly within the medium-high temperature hydrothermal systems in felsic-hosted settings,are not well studied *** we report elemental and isotopic compositions of Mg in hydrothermal chlorite-rich sediments,volcanic materials,and terrigenous sediments collected during the IODP Expedition 331 drilled to the thick sediment-covered and felsic-hosted middle Okinawa Trough(Iheya North Knoll) in the West *** investigate the sources of Mg in chlorite and Mg isotopic behavior at medium-high temperature hydrothermal *** 1 mol/L HCl leaching,Mg isotopic compositions of chlorite-rich sediments present overall similar values in the residual fractions and bulk samples albeit with slightly higher values in the *** differentiation primarily determines the Mg isotopic compositions,showing that siliciclastic residues have slightly higher δ^(26) Mg values than the leachates dominated by carbonates and oxides/*** Mg isotopic fractionation happened in the medium-high temperature(~150°C to 260°C) felsic-hosted hydrothermal system,with Δ^(26)MgChl-SW ranging from 0.15‰ to 0.71‰ and yielding a negative correlation with *** observation suggests the preferential incorporation of heavy Mg isotopes by the secondary chlorite *** infer that the medium-high temperature hydrothermal systems can take up about 8–14% of riverine input of Mg in the arc and back-arc *** removal of aqueous Mg in porewater and vent fluids by the medium-high temperature hydrothermal alterations in the arc and back-arc basins provides constraints on the Mg budget and isotopic composition of seawater.

关键词： Hydrothermal alteration Chlorite Okinawa Trough Magnesium(Mg)isotopes Integrated Ocean Drilling Program

卷取工艺对22MnB5钢氧化铁皮组织演变及酸洗的影响

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塑性工程学报 2024年第5期31卷 79-86页

作者：田飞张淇吴彦欣朱蓉李雷李晓少江海涛湖南华菱涟源钢铁有限公司研究院湖南娄底417009 北京科技大学高效轧制与智能制造国家工程研究中心北京100083

以22MnB5热成形钢在不同热履历下的氧化行为作为研究对象,使用EBSD等技术对氧化铁皮物相进行了表征,运用热轧热履历模拟、酸洗电化学实验等研究手段对热轧卷取工艺对22MnB5氧化铁皮组织演变及酸洗的影响进行了研究。结果表明,卷取温度影... 详细信息

以22MnB5热成形钢在不同热履历下的氧化行为作为研究对象,使用EBSD等技术对氧化铁皮物相进行了表征,运用热轧热履历模拟、酸洗电化学实验等研究手段对热轧卷取工艺对22MnB5氧化铁皮组织演变及酸洗的影响进行了研究。结果表明,卷取温度影响22MnB5的氧化铁皮结构和内氧化的产生倾向,进而对其酸洗性能造成影响。卷取温度越高,氧化铁皮越难以酸洗,内氧化倾向增加,酸洗时间增加,表面粗糙度增大。卷取温度低于600℃有利于提高22MnB5热轧板的酸洗效率和酸洗后的表面质量。

关键词： 22MnB5 卷取工艺氧化铁皮酸洗

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体外不同温度下人类精子活力随时间的变化

中国男科学杂志 2024年第3期38卷 43-47页

作者：罗怡云刘章顺史晓红王明燚谢晓东邵红芳上海交通大学医学院附属第六人民医院生殖医学中心上海200233

目的了解人类精子在体外不同温度条件下其活力随时间的变化趋势,为优化精子的体外保存条件提供理论依据。方法正常男性精液39份均分为两份,分别放置于26℃的室温和37℃的水浴箱中,在0 h、2 h、4 h、24 h分别测定精子活力、前向运动、非... 详细信息

目的了解人类精子在体外不同温度条件下其活力随时间的变化趋势,为优化精子的体外保存条件提供理论依据。方法正常男性精液39份均分为两份,分别放置于26℃的室温和37℃的水浴箱中,在0 h、2 h、4 h、24 h分别测定精子活力、前向运动、非前向运动和不动精子的比例;将0 h和24 h的精液分别送细菌培养。结果在0 h 39份精液中精子活动力55.68%(IQR,46.06%~64.93%),在26℃和37℃放置2 h精子活动力分别降为37.04%(IQR,30.35%~48.40%)和44.69%(IQR,33.10%~55.42%)(P<0.05);26℃24 h精子活动力为10.39%(IQR,4.39%~17.62%),而在37℃24 h所有精子活动力为0%(P<0.0001)。放置37℃和26℃2 h前向运动精子比例为33.26%(IQR,23.92%~44.58%)和28.67%(IQR,19.41%~35.07%)(P<0.05),24 h后在37℃条件下前向运动精子和非前向运动精子比例均为0%,而在26℃条件下前向运动和非前向运动精子比例分别为3.57%(IQR,1.65%~8.06%)和5.88%(IQR,2.19%~10.07%)(P<0.0001)。2 h后37℃不动精子比例[55.31%(IQR,44.42%~66.56%)]低于26℃条件下的[61.99%(50.80%~69.24%)](P<0.05);24 h后37℃不动精子的比例达到了100%,而26℃不动精子比例为89.51%(IQR,81.78%~95.44%)(P<0.0001)。0 h精液培养无细菌生长,24 h精液培养示蜡样芽胞杆菌生长。结论在体外,人类精子活力随时间延长而下降,短时间(4 h)内精子活力在37℃下降较慢,时间延长后在37℃下降更快。精子活力下降可能与精液内细菌生长繁殖有关。

关键词：精子能动性体外温度

A new building block with intramolecular D-A character for conjugated polymers: ladder structure based on B←N unit

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Science China Chemistry 2019年第10期62卷 1387-1392页

作者： Xingxin shao Chuandong Dou Jun Liu Lixiang Wang State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Science and Technology of China School of Applied Chemistry and EngineeringHefei 230026China

The general strategy to construct D-A type conjugated polymers is alternating copolymerization of electron-donating(D)monomer and electron-accepting(A)*** this article,we report a new strategy to develop D-A type conjugated polymers,*** fuse the D and A units into a polycyclic structure to produce a building block and then polymerize the building block with another *** develop a new building block with ladder structure based on B←N unit,B←N bridged dipyridylbenzene(BNDPB).In the skeleton of BNDPB,one diamine-substituted phenylene ring(D unit)and two B←N-linked pyridyl rings(A unit)are fused together to produce the polycyclic *** to the presence of intramolecular D-A character,the building block itself exhibits narrow bandgap of 1.74 *** conjugated polymers based on BNDPB show unique electronic structures,*** HOMOs and delocalized LUMOs,which are rarely observed for conventional D-A conjugated *** polymers exhibit smaller bandgap than that of the building block BNDPB and display near-infrared(NIR)light absorption(λabs=ca.700 nm).This study thus provides not only a new strategy to design D-A conjugated polymers but also a new kind of building block with narrow bandgap.

关键词： D-A character conjugated polymers building block ladder structure B-N unit

东秦岭卢氏盆地中始新世沉积-充填过程及其驱动机制

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第四纪研究 2024年第2期44卷 265-281页

作者：吕帆鹿化煜张瀚之赖文邵可涵梁承弘高鑫南京大学地理与海洋科学学院江苏南京210023

秦岭山间盆地发育的厚层新生代沉积,对于认识秦岭新生代地貌演化及东亚环境变化具有重要意义。但是,对东秦岭地区众多中-新生代山间断陷盆地的沉积-充填过程及其记录的构造、气候信息研究不够。本研究对东秦岭卢氏盆地中始新世河湖相沉... 详细信息

秦岭山间盆地发育的厚层新生代沉积,对于认识秦岭新生代地貌演化及东亚环境变化具有重要意义。但是,对东秦岭地区众多中-新生代山间断陷盆地的沉积-充填过程及其记录的构造、气候信息研究不够。本研究对东秦岭卢氏盆地中始新世河湖相沉积展开沉积学与物源分析,测试了27个层位的碎屑锆石U-Pb年龄。盆地中始新世地层自下而上可划分为张家村组、卢氏组和大峪组。张家村组为冲积扇-河流相沉积,卢氏组为浅湖-半深湖相沉积,大峪组为河流-冲积扇相沉积。张家村组和卢氏组锆石U-Pb年龄均以200~250 Ma(T-J)和400~500Ma(D-S-O-■)为主要特征峰,700~1000 Ma(Pt_(3))为次要峰,部分样品具有1800 Ma(Pt_(1))、 2500 Ma(Ar3)的年龄峰值,通过与周边地区地质资料比对,认为张家村组、卢氏组沉积物主要来自于相对远源的北秦岭造山带和南秦岭造山带。大峪组下部锆石U-Pb年龄以1000~1100 Ma(Pt_(2))、 1800 Ma(Pt_(1))和2300 Ma(Pt_(1))为特征峰值,物源转变成以近源的北秦岭造山带和华北克拉通南缘两个构造单元为主。近源的物质贡献先升高后降低,可能与河流溯源侵蚀作用有关。大峪组上部地层沉积环境转变为冲积扇,130 Ma(K)的锆石占比加大,可能与东南方栾川地区晚中生代花岗岩的抬升-剥露有关。卢氏盆地中始新世河湖相沉积序列揭示了卢氏古湖从形成到消亡的过程和山-盆地貌侵蚀、搬运和堆积的历史,并记录了秦岭山脉两期区域隆升事件。

关键词：卢氏盆地中始新世锆石U-Pb年龄盆地充填东秦岭

What is the mass of loess in the Loess Plateau of China?

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Science Bulletin 2019年第8期64卷 534-539页

作者： Yuanjun Zhu Xiaoxu Jia Jiangbo Qiao Ming'an shao State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F University Institute of Soil and Water Conservation Chinese Academy of Sciences & Ministry of Water Resources College of Resources and Environment University of Chinese Academy of Sciences Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences

The Loess Plateau of China(LP) has the largest and thickest loess deposits in the world. Quantifying the amount of loess in the LP is crucial for investigating the accumulation and erosion of loess, and determining the regional soil and water resource capacity. We used loess thickness data, a pedotransfer function for bulk density(BD), and the clay content data observed in 242 sites across the LP to derive the BD of loess and then estimate the loess mass and its distribution across the LP. The results indicated that the average BD of loess between the surface and bedrock is 1.58 g cm^(-3), varying from 1.18 to 1.87 g cm^(-3).The total loess mass is approximately 5.45 ? 10^(13) t, and the average loess mass over an area of 1 m^2 is 169 t, ranging from 1.36 to 585 t. The greatest mass of loess is in the south-central of the LP while the lowest mass of loess is in the northwest and river valley areas. Our estimate of loess mass provides key data for calculating water, carbon, and nutrient storages in the LP, which improves our understanding of soil-water processes and ecohydrological systems in this landscape.

关键词： The Loess Plateau Loess mass Pedotransfer function Soil erosion Bulk density

ZrO_2/SiO_2多层膜中膜厚组合周期数及基底材料对残余应力的影响

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物理学报 2005年第7期54卷 3312-3316页

作者：邵淑英范正修邵建达中科院上海光学精密机械研究所光学薄膜技术研究与发展中心中国科学院研究生院北京100864

ZrO2/SiO2多层膜由相同沉积条件下的电子束蒸发方法制备而成,通过改变多层膜中高(ZrO2)、低(SiO2)折射率材料膜厚组合周期数的方法,研究了沉积在熔石英和BK7玻璃基底上多层膜中残余应力的变化.用ZYGO光学干涉仪测量了基底镀膜前后曲率... 详细信息

ZrO2/SiO2多层膜由相同沉积条件下的电子束蒸发方法制备而成,通过改变多层膜中高(ZrO2)、低(SiO2)折射率材料膜厚组合周期数的方法,研究了沉积在熔石英和BK7玻璃基底上多层膜中残余应力的变化.用ZYGO光学干涉仪测量了基底镀膜前后曲率半径的变化,并确定了薄膜中的残余应力.结果发现,该多层膜中的残余应力为压应力,随着薄膜中膜厚组合周期数的增加,压应力值逐渐减小.而且在相同条件下,石英基底上所沉积多层膜中的压应力值要小于BK7玻璃基底上所沉积多层膜中的压应力值.用x射线衍射技术测量分析了膜厚组合周期数不同的ZrO2/SiO2多层膜微结构,发现随着周期数增加,多层膜的结晶程度增强.同时多层膜的微结构应变表现出了与所测应力不一致的变化趋势,这主要是由多层膜中,膜层界面之间复杂的相互作用引起的.

关键词：残余应力 SiO2 ZrO2 多层膜周期数组合膜厚基底材料 X射线衍射技术玻璃基底电子束蒸发光学干涉仪应力值沉积条件曲率半径测量分析石英基底变化趋势结构应变结晶程度相互作用折射率熔石英压应力微结构

和谐医患关系视角下抑郁症患者“知信行”管理模式的构建与实施

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中国公共卫生管理 2024年第2期40卷 293-296页

作者：黄炊琴邵亦娟邵璟雷丹唐燕萍浙江省建德市第四人民医院浙江建德311612

目的构建抑郁症患者“知信行”管理模式,并分析其实施效果。方法采用简单随机抽样的方法选取2021年6月—2023年6月浙江省建德市第四人民医院收治的120例抑郁症患者作为研究对象。采用随机数字表法将其分为观察组、对照组,每组各60例。... 详细信息

目的构建抑郁症患者“知信行”管理模式,并分析其实施效果。方法采用简单随机抽样的方法选取2021年6月—2023年6月浙江省建德市第四人民医院收治的120例抑郁症患者作为研究对象。采用随机数字表法将其分为观察组、对照组,每组各60例。对照组实施常规管理模式,观察组实施“知信行”管理模式。结果干预后,观察组患者抑郁症病耻感量表总分为(38.87±5.05)分,低于对照组的(43.00±5.51)分(t=-4.282,P<0.001);服药必要性评分为(4.23±0.53)分,高于对照组的(3.82±0.39)分(t=4.906,P<0.001);服药顾虑评分为(1.57±0.53)分,低于对照组的(2.41±0.53)分(t=-8.692,P<0.001)。干预后,观察组患者服药依从性和满意度优于对照组(均P<0.05)。结论抑郁症患者“知信行”管理模式的实施有利于改善抑郁症患者病耻感,提升其服药依从性和满意度,有利于促进医患关系和谐发展。

关键词：医患关系抑郁症知信行管理模式