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Dynamic modeling and beating phenomenon analysis of space robots with continuum manipulators

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Chinese Journal of Aeronautics 2022年第9期35卷 226-241页

作者： jinzhao yang Haijun PENG Jie ZHANG Zhigang WU School of Aeronautics and Astronautics Dalian University of TechnologyDalian 116024China Department of Engineering Mechanics Dalian University of TechnologyDalian 116024China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian I16024China

Space robotics has been used extensively in complex space missions. Rigid-manipulator space robots may suffer from rigid-body collisions with targets. This collision is likely to cause damage to the space robot and the target. To overcome such a problem, a novel ContinuumManipulator Space Robot(CMSR) for performing on-orbit servicing missions is proposed in this paper. Compared with rigid-manipulator space robots, CMSRs are able to perform compliant operations and avoid rigid-body collisions with a target. The CMSR consists of two kinds of flexible components, including solar arrays and continuum manipulators. The elastic vibrations of these flexible components disturb the position and attitude of CMSRs. The beating phenomenon introduced by the energy transfer among these flexible components can cause damage to solar *** complicated dynamic coupling poses enormous challenges in dynamic modeling and vibration analysis. The dynamic model for CMSRs is derived and the mechanism of the beating phenomenon is analyzed in this paper. Simulation results show that an obvious beating phenomenon occurs and the amplitude of the solar arrays increases significantly when the natural frequencies of two kinds of flexible components are close. A method is provided to avoid the beating phenomenon.

关键词： Continuum manipulators Dynamic model Solar arrays Space robots Vibration analysis

Mechanistic Analysis and Bio-inspired Applications for a Bidirectional Stiffness of a Water Snail Operculum

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Journal of Bionic Engineering 2023年第5期20卷 1930-1941页

作者： Ke Xu Xiaoming Xu Qi yang Jianing Wu Zhigang Wu jinzhao yang School of Aeronautics and Astronautics Sun Yat-Sen UniversityShenzhen518107China Shenzhen Key Laboratory of Intelligent Microsatellite Constellation Shenzhen Campus of Sun Yat-Sen UniversityShenzhen518107China School of Engineering and Technology China University of Geosciences(Beijing)Beijing100083China School of Advanced Manufacturing Sun Yat-Sen UniversityShenzhen518107China

The water snail Pomacea canaliculata retracts the discoidal and multi-layered operculum to protect the soft body from being attacked by predators,and releases it when threats ***,the duration of the operculum retraction is usually less than that of the operculum *** this paper,we elucidate the biological compliant mechanism of the *** using confocal laser scanning microscopy,we find that the operculum has compliant sandwiched layers between hard *** layered structure results in a compliant mechanism with a bidirectional stiffness for the locking and unlocking processes of the operculum.A mathematical model is derived to rationalize the bidirectional stiffness mechanism of the *** addition,we carry out the experiments on the locking and unlocking *** experimental results show that the locking tension is about two-fifths of the unlocking tension of the ***,based on the mechanical properties of the operculum with the layered structure,we designed an operculum-inspired structure,which may have a variety of potential applications in combined driving patterns.

关键词： Water snail Operculum Multi-layered structure Bidirectional stiffness Compliant mechanism

医用臭氧自体血回输在肝癌患者介入治疗中的应用效果

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中外医药研究 2024年第10期3卷 24-26页

作者：杨明惠伍秀娟刘瑶杨锦钊梁格江门市中心医院广东江门529000

目的:探讨医用臭氧自体血回输在肝癌患者介入治疗中的应用效果.方法:选取2022年4月—2023年11月于江门市中心医院行介入治疗的肝癌患者120例作为观察对象,以随机数字表法分为对照组(接受常规护理)和观察组(在对照组基础上给予医用臭氧... 详细信息

目的:探讨医用臭氧自体血回输在肝癌患者介入治疗中的应用效果.方法:选取2022年4月—2023年11月于江门市中心医院行介入治疗的肝癌患者120例作为观察对象,以随机数字表法分为对照组(接受常规护理)和观察组(在对照组基础上给予医用臭氧自体血回输干预),各60例.比较两组疼痛评分与疼痛控制情况、术后恢复指标、自我护理能力.结果:干预后,两组Prince-Henry评分均下降,观察组低于对照组,差异有统计学意义(P<0.05);观察组疼痛控制率高于对照组,差异有统计学意义(P=0.0281).观察组首次下床活动时间、首次排气时间、首次排便时间、首次进食时间早于对照组,总住院时间短于对照组,差异有统计学意义(P<0.0001).干预后,两组自我护理能力测定量表评分均升高,观察组高于对照组,差异有统计学意义(P<0.05).结论:针对肝癌介入治疗患者,联合医用臭氧自体血回输干预,能够有效减轻术后疼痛程度,提高疼痛控制效果,促进患者术后康复,提高自我护理能力.

关键词：医用臭氧自体血回输肝癌介入治疗

BSIN: A Behavior Schema of Information Networks Based on Approximate Bisimulation

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Tsinghua Science and Technology 2024年第4期29卷 1092-1104页

作者： Wujie Hu jinzhao Wu School of Electrical Engineering Guangxi UniversityNanning 530004China

Information networks are becoming increasingly important in practice. However, their escalating complexity is gradually impeding the efficiency of data mining. A novel network schema called the Behavior Schema of Information Networks (BSIN) is proposed to address this issue. This work defines the behavior of nodes as connected paths in BSIN, proposes a novel function distinguish behavior differences, and introduces approximate bisimulation into the acquisition of quotient sets for node types. The major highlight of BSIN is its ability to directly obtain a high-efficiency network on the basis of approximate bisimulation, rather than reducing the existing information network. It provides an effective representation of information networks, and the resulting novel network has a simple structure that more efficiently expresses semantic information than current network representations. The theoretical analysis of the connected paths between the original and the obtained networks demonstrates that errors are controllable;and semantic information is approximately retained. Case studies show that BSIN yields a simple network and is highly cost-effective.

关键词： data mining information network approximate bisimulation controllable error

Insights into the provenance implication of leaf wax n-alkanes along the lower Yellow River

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Science China Earth Sciences 2024年第6期67卷 2001-2018页

作者： Liang ZHANG jinzhao LIU Chong JIANG Fei ZHANG Zhisheng AN School of Human Settlements and Civil Engineering Xi’an Jiaotong UniversityXi’an 710054China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China National Observation and Research Station of Earth Critical Zone on the Loess Plateau of Shaanxi Xi’an 710061China

Serving as one of the largest rivers in terms of both sediment and organic carbon transport fluxes in the world,the Yellow River plays a crucial role in regional biogeochemical process as well as in the global carbon ***,although a large number of studies have been carried out on the flux,composition,source and seasonal variation of total particulate organic carbon in the Yellow River so far,studies on molecular biomarkers at different spatial and temporal scales are still *** this study,we focus on the molecular and hydrogen isotopic properties of leaf wax n-alkanes among different types of samples which obtained from different seasons(flood ***-flood)along the lower Yellow *** molecular distribution of n-alkanes show that the riparian topsoils are subject to inputs from the overlying vegetation,while the suspended sediments from the flood season are characterized by the mixing of soil materials which originate from various stratigraphy with different ages on the Chinese Loess *** to the contrasting hydrodynamic conditions,the n-alkanes in suspended sediments also show distinct molecular composition between flood and non-flood ***,considering the effect of climatic factors,the proportion of monocots in flood-season suspended sediments is calculated from a semi-quantitative perspective using δ^(2)H_(wax).Our findings may bring to light new considerations for the interpretation of leaf wax proxies in studies of organic matter sources of Yellow River.

关键词： Molecular distribution Hydrogen isotopic composition Leaf wax n-alkanes Suspended sediments Lower Yellow River

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初盛唐丝路碑志文的文学成就

西安交通大学学报（社会科学版） 2017年第1期37卷 107-113页

作者：李慧杨金钊西安交通大学人文社会科学学院陕西西安710049

初盛唐是古文转捩的关键时期,这一时期的丝路碑志文对古文的求变求新有着一定的助推作用;初盛唐文人以积极进取的时代精神及重气轻身的家国情怀,在丝路碑志文中为后人纪录了有唐一代的隆治气象,并塑造了一批壮志许国的盛世英雄群像;碑... 详细信息

初盛唐是古文转捩的关键时期,这一时期的丝路碑志文对古文的求变求新有着一定的助推作用;初盛唐文人以积极进取的时代精神及重气轻身的家国情怀,在丝路碑志文中为后人纪录了有唐一代的隆治气象,并塑造了一批壮志许国的盛世英雄群像;碑志文与此时的"边塞诗"相辉映,共同成就了初盛唐的文学大观。

关键词：初盛唐丝路碑志文边塞诗家国情怀

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计算机辅助工程技术在塑料注射成型中的应用

合成树脂及塑料 2016年第4期33卷 64-66页

作者：杨进钊吴涛唐山工业职业技术学院河北省唐山市063020 华北理工大学河北省唐山市063009

利用计算机辅助工程技术对塑料注射成型工艺及其模具结构设计进行了探讨。计算机辅助工程技术能够在模具设计阶段开展模拟工作,一旦发现问题,则会及时解决,同时也能运用计算机模拟并确定注射成型所需的工艺参数。通过选择塑料注射成型... 详细信息

利用计算机辅助工程技术对塑料注射成型工艺及其模具结构设计进行了探讨。计算机辅助工程技术能够在模具设计阶段开展模拟工作,一旦发现问题,则会及时解决,同时也能运用计算机模拟并确定注射成型所需的工艺参数。通过选择塑料注射成型工艺参数,力图将工艺参数与模具结构紧密融合。最后,用实例验证了运用计算机辅助工程技术模拟注射成型工艺及模具结构设计的过程,达到了提高注射成型制品质量的目的。

关键词：塑料注射成型计算机辅助工程技术模具工艺参数

Plant type effect overweighs seasonal variation in n-alkanoic acid biomarker on regional Loess Plateau of China

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Science China Earth Sciences 2024年第8期67卷 2547-2562页

作者： jinzhao LIU S.Nemiah LADD Jiaju ZHAO Dongna YAN Ding HE Yunning CAO Zhisheng AN State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China CAS Center for Excellence in Quaternary Science and Global Change Xi’an 710061China Department of Environmental Sciences University of BaselBasel 4056Switzerland Department of Ocean Science and Center for Ocean Research in Hong Kong and Macao The Hong Kong University of Science and TechnologyHong Kong 999077China

The effect of plant type on n-alkane biomarker has been widely studied,but the influence of plant type on n-alkanoic acids(n-FAs)has received less *** the effect of the distribution of n-FAs and their hydrogen isotope composition(δ^(2)H_(FA))is critical for interpreting sedimentaryδ^(2)H_(FA)values as proxies of hydroclimate and/or vegetation *** this study,we systematically investigated the distribution ofn-FAs andδ^(2)H_(FA)values across seasons on the Chinese Loess Plateau(CLP).Our results showed that there were no significant seasonal differences in n-FAs distribution andδ^(2)H_(FA)values,but there were significant differences inδ^(2)H_(FA)values across plant ***δ^(2)H_(FA)values ranged from-185‰to-125‰in dicots(-161‰±28‰),and from-215‰to-170‰in monocots(-196‰±22‰)on the *** fractionation betweenδ^(2)H_(FA)values and precipitationδ^(2)H(ε_(FA-P))was also^(2)H-enriched in dicots relative to *** the regional scale of the CLP,δ^(2)H_(FA)values were not correlated withδ^(2)H values of ***,δ^(2)H_(FA)values from the CLP were similar to expectations from a global comparison,both in terms of their mean values and high variability among plants growing in sites with similarδ^(2)H values of *** some of this variability inεFA-Pis due to the effect of plant type,a careful assessment of the likely sources of waxes in terrestrial sediments is critical when usingδ^(2)H_(FA)values for paleohydroclimate reconstruction.

关键词： n-Alkanoic acid Hydrogen isotope Plant type Paleohydroclimate Chinese Loess Plateau

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粉末燃料冲压发动机内镁粉尘云层流燃烧模型

国防科技大学学报 2013年第5期35卷 13-19页

作者：杨晋朝夏智勋胡建新国防科技大学高超声速冲压发动机技术重点实验室湖南长沙410073

对粉末燃料冲压发动机预燃室内镁粉尘云燃烧过程进行了研究,建立了镁粉尘云的一维层流预混燃烧模型.研究表明,镁粉尘云层流火焰传播很稳定,燃烧过程中火焰结构基本不变,燃烧区很薄,而预热区厚度约是燃烧区的2～3倍.粉尘云中镁颗粒的蒸... 详细信息

对粉末燃料冲压发动机预燃室内镁粉尘云燃烧过程进行了研究,建立了镁粉尘云的一维层流预混燃烧模型.研究表明,镁粉尘云层流火焰传播很稳定,燃烧过程中火焰结构基本不变,燃烧区很薄,而预热区厚度约是燃烧区的2～3倍.粉尘云中镁颗粒的蒸发和气相镁与氧气的均相反应是产生火焰的直接原因,也是火焰得以传播的关键.预热区气相温度升高主要靠燃烧区气体的导热和扩散过来的气相镁与氧气反应释放热量,而预热区颗粒相温度升高主要靠气相对其对流传热.分析了各参数对粉尘云燃烧的影响,颗粒相对浓度对粉尘云燃烧的影响比较复杂,在浓度较低的情况下,增大颗粒相对浓度有利于粉尘云快速燃烧;而在浓度较高的情况下,增大颗粒相对浓度则不利于粉尘云快速燃烧.随颗粒粒径的增加,火焰传播速度减小,火焰温度升高,预热区厚度增大.火焰传播速度和火焰温度随粉尘云初温增加线性增长,预热区厚度随粉尘云初温增加抛物线增长.数值模拟与文献中试验结果的变化趋势相一致.

关键词：粉末燃料冲压发动机粉尘云层流火焰镁燃烧