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APPROACH TO FAULT ON-LINE DETECTION AND DIAGNOSIS BASED ON NEURAL NETWORKS FOR ROBOT IN FMS

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Chinese Journal of Mechanical Engineering 1998年第2期11卷 36-42页

作者： Shi, Tianyun zhang, zhijing Wang, Xinyi Zhu, Xiaoyan Beijing Inst of Technology China

Based on radial basis function (RBF) neural networks, the healthy working model of each sub system of robot in FMS is established. A new approach to fault on line detection and diagnosis according to neural networks model is presented. Fault double detection based on neural network model and threshold judgement and quick fault identification based on multi layer feedforward neural networks are applied, which can meet quickness and reliability of fault detection and diagnosis for robot in FMS.

关键词： Neural networks Robot in FMS Fault detection Fault diagnosis

A Chemo-enzymatic Route for the Preparation of Chiral （S）-3-Hydroxy-3-phenylpropanoic Acid

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Chemical Research in Chinese Universities 2014年第6期30卷 915-918页

作者： ZHAO Ying MA Haiping FU zhijing zhang Guoyan College of Chemistry Jilin University Changchun 130012 P. R. China

（S）-3-Hydroxy-3-phenylpropanoic acid is a potential progenitor of optically pure tomoxetine hydrochlo- ride and fluoxetine hydrochloride which are currently available antidepressant drugs. We report here the chemical synthesis of racemic substrate （R,S）-ethyl 3-hydroxy-3-phenylpropanoate and enzymatic preparation of S-isomer of the substrate by employing Porcine pancreas lipase（PPL） as a biocatalyst. Optimum enzyme-catalyzed reaction con- ditions, such as the effects of the temperature, pH and solvents on conversion degree and enantiomeric excess, were studied. An optimal temperature of 35 ℃ and pH=7.5 are the best for the resolution of （R,S）-ethyl 3-hydroxy-3- pheylpropanoate by PPL when 0.1 mol/L phosphate buffer solution acts as a medium. This work provides a practi- cally chemo-enzvmatic oreoaration of chiral β-hvdroxv acid by PPL.

关键词： Optically active β-hydroxy acid Porcine pancreas lipase(PPL) Chemo-enzymatic process

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油气储层勘探建模技术新进展及未来展望

油气地质与采收率 2024年第4期31卷 135-153页

作者：罗红梅王长江张志敬房亮管晓燕郑文召中国石化胜利油田分公司勘探开发研究院山东东营257015

油气储层建模利用地质统计学等方法,综合测井、地质、地震等多学科信息,是油气田开发研究的利器,油藏地质模型可以将油藏各种地质特征在三维空间的变化及分布定量表征出来,是油气藏的类型、几何形态、规模、油藏内部结构、储层参数及流... 详细信息

油气储层建模利用地质统计学等方法,综合测井、地质、地震等多学科信息,是油气田开发研究的利器,油藏地质模型可以将油藏各种地质特征在三维空间的变化及分布定量表征出来,是油气藏的类型、几何形态、规模、油藏内部结构、储层参数及流体分布的高度概括,储层地质模型是油藏地质模型的核心,可以对储层的沉积特征、非均质性、物性及流体等特征进行综合表征。但在勘探阶段,面对大尺度沉积体系和稀疏井网条件下的储层展布规律表征的建模难点为:①地质知识的量化表达问题,包括地质专家的经验认识如何数字化表征。②稀疏井网条件下无法直接用钻井资料对地质体的发育规模、展布方向和结构特征准确定量描述及构建地质模式,大尺度空间中复杂沉积体系无法用简单数学函数表征。③传统地质统计学等方法在勘探模型构建中如何实现地震、测井、地质、油藏等多维度数据的融合问题。因此,基于确定性建模和传统地质统计学等随机建模的储层建模理论和技术遇到极大挑战。笔者在系统剖析传统储层建模技术流程和方法的基础上,通过构建涵盖地质、测井、地震、分析化验等信息的多学科地学大数据知识库,开展多维数据凝聚层次聚类的沉积相模式库表征和基于生成式网络的智能建模,提出了多学科协同的油气储层勘探建模技术对策及技术体系,实现了构造、沉积及储层之间匹配关系的定量表征。该技术体系在东营凹陷北部陡坡带、洼陷带勘探部署中开展系统应用,构建融合古地貌、古物源、搬运通道、测井及地震属性等多信息的岩相、物性及油气运聚的地质模型,基于模型新范式指导部署井位,支撑了陆相断陷盆地复杂砂砾岩体、页岩油等勘探实践。笔者通过深度剖析东营凹陷北部陡坡带勘探建模实践难点及精度问题,进一步探讨了未来油气储层勘探建模技术发展趋势和应用前景。

关键词：储层勘探建模地学大数据知识库相模式库生成对抗网络智能建模

AUTOREGRESSIVE MODEL AND POWER SPECTRUM CHARATERISTICS OF CURRENT SIGNAL IN HIGH FREQUENCY GROUP PULSE MICRO-ELECTROCHEMICAL MACHINING

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Chinese Journal of Mechanical Engineering 2006年第2期19卷 260-264页

作者： TANG Xinglun zhang zhijing ZHOU Zhaoying YANG Xiaodong Department of Precision Instrument ＆ Mechanics Tsinghua UniversityBeijing 100084 China School of Mechanical ＆ Vehicle Engineering Beijing Institute of TechnologyBeijing 100084 China Equipment ＆ Energy Department Guizhou Branch of Aluminum Co. Ltd.Guiyang 550014 China

The identification of the inter-electrode gap size in the high frequency group pulse micro-electrochemical machining （HGPECM） is mainly discussed. The auto-regressive（AR） model of group pulse current flowing across the cathode and the anode are created under different situations with different processing parameters and inter-electrode gap size. The AR model based on the current signals indicates that the order of the AR model is obviously different relating to the different processing conditions and the inter-electrode gap size; Moreover, it is different about the stability of the dynamic system, i.e. the white noise response of the Green＇s function of the dynamic system is diverse. In addition, power spectrum method is used in the analysis of the dynamic time series about the current signals with different inter-electrode gap size, the results show that there exists a strongest power spectrum peak, characteristic power spectrum（CPS）, to the current signals related to the different inter-electrode gap size in the range of 0～5 kHz. Therefore, the CPS of current signals can implement the identification of the inter-electrode gap.

关键词： Electrochemical machining Inter-electrode gap Autoregressive(AR) model Power spectrum

Lattice Boltzmann simulation study of anode degradation in solid oxide fuel cells during the initial aging process

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 405-411页

作者： Shixue Liu zhijing Liu Shuxing zhang Hao Wu Hydrogen Energy Industrial Technology Innovation Center China Nuclear Power Technology Research InstituteShenzhen 518031China Shenzhen Engineering Research Center for Hydrogen Safety Shenzhen 518031China

For present solid oxide fuel cells(SOFCs),rapid performance degradation is observed in the initial aging process,and the dis-cussion of the degradation mechanism necessitates quantitative ***,focused ion beam-scanning electron microscopy was em-ployed to characterize and reconstruct the ceramic microstructures of SOFC *** lattice Boltzmann method(LBM)simulation of multiphysical and electrochemical processes in the reconstructed models was *** samples collected from industrial-size cells were characterized,including a reduced reference cell and a cell with an initial aging *** parameters of the reconstructed microstructures revealed a significant decrease in the active triple-phase boundary and Ni connectivity in the aged cell compared with the reference *** LBM simulation revealed that activity degradation is dominant compared with microstructural degradation during the initial aging process,and the electrochemical reactions spread to the support layer in the aged *** microstructural and activity de-gradations are attributed to Ni migration and coarsening.

关键词： solid oxide fuel cell anode degradation focused ion beam-scanning electron microscopy lattice Boltzmann method

Self-luminescence and color-tunable emission in KYb_3F_(10) matrix under different excited sources

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Journal of Rare Earths 2020年第7期38卷 689-696,I0001页

作者： Lili Han zhijing zhang Jiang Chen Yirun Zhu Dongcheng Zhu Juan Zhao Wei Shen Zhipeng Ci Key Laboratory of Atomic and Molecular Physics&Functional Materials of Gansu Province College of Physics and Electronic EngineeringNorthwest Normal UniversityLanzhou 730070China Key Laboratory of Special Function Materials and Structure Design Ministry of EducationLanzhou UniversityLanzhou 730000China National&Local Joint Engineering Laboratory for Optical Conversion Materials and Technology Lanzhou UniversityLanzhou 730000China

A self-luminescence KYb3 F10 material was obtained via a mild hydrothermal *** structure,morphology and the corresponding luminescence properties were *** is a self-luminesce nce based on the effective recombination of electron and hole on surface defects or electronic centers in KYb3 *** pH values have significant impact on crystallinity and self-luminescent intensity of target *** the introduction of Tb3+and Eu3+into KYb3 F10 matrix,a series of color-tunable emission can be ***,Tb3+and Eu3+can also affect the self-luminescent intensity of host *** there is no obvious energy transfer between host and activators,Tb3+has a distinct sensitive effect on Eu3+ascribed to the energy transfer between Tb3+and Eu3+.In addition,the thermal stability was carefully investigated,which demonstrate the materials can be as a candidate in fluorescent lamps and displays.

关键词： KYb3F10 Self-luminescence Color-tunable emission Rare earths

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数字电子技术课程思政达成度分析

实验室科学 2024年第5期27卷 212-217页

作者：陈俊鑫王鸿博张芷境蒋芳芳大连理工大学软件学院辽宁大连116024 伦敦帝国理工学院生物工程学院伦敦SW72AZ 东北大学医学与生物信息工程学院辽宁沈阳110169

课程思政是构建全员、全程、全课程育人体系的重要环节,可与思想政治理论课同向同行,提升全方位育人效果。为了分析“数字电子技术”课程的课程思政达成度,通过调查问卷获得数据并使用SPSS对收集的数据进行信度分析、效度分析以及主成... 详细信息

课程思政是构建全员、全程、全课程育人体系的重要环节,可与思想政治理论课同向同行,提升全方位育人效果。为了分析“数字电子技术”课程的课程思政达成度,通过调查问卷获得数据并使用SPSS对收集的数据进行信度分析、效度分析以及主成分分析,进而对数据进行降为并分析各个主成分所对应的实际意义,最终获得学生对不同思政点的了解程度,分析明确了该课程思政的重点内容和落实举措与重要意义。

关键词：课程思政数字电路主成分分析教学育人

Chiral rhodium(Ⅱ)-catalyzed asymmetric aldol-type interception of an oxonium ylide to assemble chiral 2,3-dihydropyrans

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Science China Chemistry 2022年第8期65卷 1607-1614页

作者： Aimin Xu Xiaoyu Zhou Rimei Zheng zhijing zhang Xinru Yin Kemiao Hong Zhuofeng Ke Yu Qian Wenhao Hu Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery School of Pharmaceutical SciencesSun Yat-sen UniversityGuangzhou 510006China School of Materials Science&Engineering Sun Yat-sen UniversityGuangzhou 510006China

A chiral dirhodium complex is an effective and robust catalyst for asymmetric carbene ***,dirhodiumcatalyzed asymmetric ylide interception processes are rare,mainly because of the dissociation of the metal catalyst before the stereo-determining ***,we report a chiral dirhodium(Ⅱ)-catalyzed asymmetric annulation of vinyl diazoesters withα-hydroxyl ketones,which provides an efficient way to form chiral 2,3-dihydropyrans in good yields with excellent diastereoselectivities and *** article is the first example of the chiral dirhodium complex–controlled asymmetric aldol-type interception of an in situ–formed oxonium *** origin of the high stereoselectivity is well expounded via experimental and computational *** generated chiral products exhibit potent antiproliferation activity in three tested cancer cell lines,namely HCT116(colon cancer),A549(lung adenocarcinoma),and SJSA-1(osteosarcoma cancer).

关键词： asymmetric aldol-type interception oxonium ylide 2 3-dihydropyrans antiproliferation activity

DIP支付模式下公立医院运营管理优化路径研究

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现代医院 2024年第2期24卷 165-167,171页

作者：何慧莹张萍汤广龄张芷菁费凡钟敏华中山大学附属第一医院广东广州510080

随着公立医院综合改革进入深水区,粗放的运营管理已不符合高质量发展的需要。文章探讨了DIP支付模式下医院运营管理的现状问题,探索提出了优化路径及落地实践的要点,即以病种组合及分值为基础,实施预算绩效一体化闭环的资源配置策略、... 详细信息

随着公立医院综合改革进入深水区,粗放的运营管理已不符合高质量发展的需要。文章探讨了DIP支付模式下医院运营管理的现状问题,探索提出了优化路径及落地实践的要点,即以病种组合及分值为基础,实施预算绩效一体化闭环的资源配置策略、提升资源效能的成本管理机制、激发人员自生管理动力的绩效分配制度,并提出了建设管理信息系统的建议,进而为DIP支付模式下公立医院提升运营管理能力提供实践参考。

关键词：运营管理 DIP支付预算管理成本管理绩效管理