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Robust Remaining Useful Life Estimation Based on an Improved Unscented Kalman Filtering Method

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Computer Modeling in Engineering & Sciences 2020年第6期123卷 1151-1173页

作者： Shenkun Zhao Chao Jiang Zhe Zhang xiangyun long State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha410082China

In the Prognostics and Health Management(PHM),remaining useful life(RUL)is very important and utilized to ensure the reliability and safety of the operation of complex mechanical ***,unscented Kalman filtering(UKF)has been applied widely in the RUL *** a degradation system,the relationship between its monitored measurements and its degradation states is assumed to be nonlinear in the conventional ***,in some special degradation systems,their monitored measurements have a linear relation with their degradation *** these special problems,it may bring estimation errors to use the UKF method ***,many uncertain factors can result in the fluctuations of the estimated results,which may have a bad influence on the RUL estimation *** a result,a robust RUL estimation approach is proposed in this paper to reduce the errors and randomness of estimation results for this kind of degradation ***,an improved unscented Kalman filtering is established utilizing the Kalman filtering(KF)method and a linear adaptive *** linear adaptive strategy is used to adjust its noise term ***,the robust RUL estimation is realized by the improved *** last,three problems are investigated to demonstrate the effectiveness of the proposed method.

关键词： Remaining useful life unscented Kalman filtering state space model

Response-surface-based structural reliability analysis with random and interval mixed uncertainties

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Science China(Technological Sciences) 2014年第7期57卷 1322-1334页

作者： HAN Xu JIANG Chao LIU LiXin LIU Jie long xiangyun State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan University

Traditional reliability analysis requires probability distributions of all the uncertain ***,in many practical applications,the variation bounds can be only determined for the parameters with limited information.A complex hybrid reliability problem then will be caused when the random and interval variables coexist in a same *** this paper,by introducing the response surface technique,we develop a new hybrid reliability method to efficiently compute the interval of the failure probability of the structure due to the probability-interval hybrid *** present method consists of a sequence of *** each step,a response surface model is constructed for the limit-state function by using a quadratic polynomial and a modified axial experimental design *** approximate hybrid reliability problem is created based on the response surface model,which is subsequently solved by an efficient decoupling *** updating strategy is suggested to improve the quality of the response surface and whereby ensure the reliability analysis precision.A computational procedure is then summarized for the whole *** numerical examples and also a practical application are provided to demonstrate the effectiveness of the present method.

关键词： structural reliability response surface mixed uncertainty model probability interval uncertain structure

Diffusion and Adsorption of Tetralin Hydrocracking Reaction on Different Zeolites by Molecular Simulation

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China Petroleum Processing & Petrochemical Technology 2021年第1期23卷 1-9页

作者： Sun Lijie Fan Yaming Dong Songtao Xian Ce long xiangyun Li Dadong SINOPEC Research Institute of Petroleum Processing Beijing 100083

Three different zeolite catalysts with different pore sizes(MFI-type,BEA-type,and FAU-type zeolites)have been *** influence of different zeolite catalysts on reactivity and product shape selectivity of tetralin is *** differences are observed in the reactivity of tetralin and distribution of products achieved by different *** diffusion and adsorption behavior of the reactant tetralin and its intermediates,n-butylbenzene and 1-methylindane under the reaction conditions are simulated using molecular simulation *** combining simulation results and experimental observations,it is shown that the difference in diffusion coefficient and competitive adsorption capacity can explain the reactivity of tetralin and the selectivity of *** steric hindrance of the MFI-type zeolite mainly limits the key step of ring opening of tetralin,leading to lower selectivity of ring-opening products.n-Butylbenzene molecules can diffuse sufficiently fast in the large pores of FAU-type zeolite and the weak adsorption capacity of n-butylbenzene leads to its insufficient *** addition,it also explains the reason that the BEA-type zeolite has the best BTX selectivity,because it can satisfy both good ring-opening activity and sufficient butylbenzene cracking depth.

关键词： hydrocracking tetralin molecular simulation diffusion competitive adsorption.

A Study on the Coking Sites ofγ-Alumina Surface Using 1-Methylnaphthalene as the Model Reactant

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China Petroleum Processing & Petrochemical Technology 2018年第4期20卷 37-43页

作者： Hu Anpeng Han Wei Zhang Le long xiangyun Li Mingfeng Nie Hong SINOPEC Research Institute of Petroleum Processing Beijing 100083

The support γ-Al_2O_3 was treated with 1-methylnaphthalene as the model reactant by respectively using the chemical static adsorption method and the accelerated coking method to study the coking sites of γ-Al_2O_3 surface. The carbon species formed on γ-Al_2O_3 surface were analyzed by CAT-CS, TG-MS, IR-OH, and Py-IR techniques. The results of characterization by CAT-CS and TG-MS techniques indicated that the carbon species formed during the chemical static adsorption process is mainly composed of the reversibly adsorbed coke precursors with a lowly-condensed state, while that formed after the accelerated coking process is probably related with the irreversibly adsorbed coke deposits with a highlycondensed state. The results of characterization by IR-OH and Py-IR techniques further implied that the formation of the two kinds of carbon species, i.e., coke precursors and coke deposits, are closely related with the basic hydroxyl groups and the strong Lewis acid sites on γ-Al_2O_3 surface. The results lead to a deep insight into the coking mechanism on the alumina surface.

关键词： 1-methylnaphthalene γ-Al2O3 coking sites chemical static adsorption accelerated coking

Electronic struture of titanium silicides

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中国有色金属学会会刊：英文版 1994年第3期4卷 25-29,35页

作者： long, xiangyun(Department of Chemistry,Central South University of Technology,Changsha 410083)Chong , Zheng(Department of Chemistry,Northern Illinois University,Dekalb 60115,U.S.A.)

ＥＬＥＣＴＲＯＮＩＣＳＴＲＵＣＴＵＲＥＯＦＴＩＴＡＮＩＵＭＳＩＬＩＣＩＤＥＳＬｏｎｇ，Ｘｉａｎｇｙｕｎ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｓｔｒｙ，ＣｅｎｔｒａｌＳｏｕｔｈＵｎｉｖｅｒｓｉｔｙｏｆＴｅｃｈｎｏｌｏｇｙ... 详细信息

ＥＬＥＣＴＲＯＮＩＣＳＴＲＵＣＴＵＲＥＯＦＴＩＴＡＮＩＵＭＳＩＬＩＣＩＤＥＳＬｏｎｇ，Ｘｉａｎｇｙｕｎ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｓｔｒｙ，ＣｅｎｔｒａｌＳｏｕｔｈＵｎｉｖｅｒｓｉｔｙｏｆＴｅｃｈｎｏｌｏｇｙ，Ｃｈａｎｇｓｈａ４１００８３）Ｃ...

关键词： titanium silicides electronic structure density of state

基于两阶段主动学习Kriging模型的广义概率区间混合可靠性分析

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机械工程学报 2022年第6期58卷 274-288页

作者：余萌晨龙湘云湖南大学汽车车身先进设计制造国家重点实验室长沙410082

提出一种基于双阶段主动学习Kriging模型的广义概率区间混合可靠性分析方法(TALK-HRA)。该TALK-HRA方法可有效处理包含概率与区间模型、区间概率模型及其组合在内的多种混合模型。首先,建立第一阶段主动学习Kriging模型以选择有可能跨... 详细信息

提出一种基于双阶段主动学习Kriging模型的广义概率区间混合可靠性分析方法(TALK-HRA)。该TALK-HRA方法可有效处理包含概率与区间模型、区间概率模型及其组合在内的多种混合模型。首先,建立第一阶段主动学习Kriging模型以选择有可能跨越极限状态面的高风险点,从而准确预测功能函数符号,并为给定区间参数下的失效概率计算奠定基础。其次,构造第二阶段的Kriging模型以学习最大或最小失效概率附近的区域,从而寻找失效概率的边界。再次,提出的TALK-HRA方法被应用到随机-模糊混合可靠性分析中。最后,通过五个算例验证该方法的有效性。结果表明,该方法不仅可以准确高效地计算多种概率区间混合模型下的可靠度,而且能应用于具有高非线性和多峰极限状态面的“黑箱”问题的可靠性分析。

关键词：主动学习Kriging模型概率和区间不确定性混合可靠性分析模糊随机可靠性

Monolayer Oxide Modification on HZSM-5 and Its Role in Selective Methylation of Toluene

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石油学报（石油加工） 1997年第S1期13卷 68-75页

作者： long xiangyun, Zhao BiyingTo whom all correspondence should be addressed., Huang Huizhong, Xie Youchang (Institute of Physical Chemistry, Peking University, Beijing 100871)

ＭｏｎｏｌａｙｅｒＯｘｉｄｅＭｏｄｉｆｉｃａｔｉｏｎｏｎＨＺＳＭ５ａｎｄＩｔｓＲｏｌｅｉｎＳｅｌｅｃｔｉｖｅＭｅｔｈｙｌａｔｉｏｎｏｆＴｏｌｕｅｎｅ①ＬｏｎｇＸｉａｎｇｙｕｎ，ＺｈａｏＢｉｙｉｎｇ②，ＨｕａｎｇＨｕ... 详细信息

ＭｏｎｏｌａｙｅｒＯｘｉｄｅＭｏｄｉｆｉｃａｔｉｏｎｏｎＨＺＳＭ５ａｎｄＩｔｓＲｏｌｅｉｎＳｅｌｅｃｔｉｖｅＭｅｔｈｙｌａｔｉｏｎｏｆＴｏｌｕｅｎｅ①ＬｏｎｇＸｉａｎｇｙｕｎ，ＺｈａｏＢｉｙｉｎｇ②，ＨｕａｎｇＨｕｉｚｈｏｎｇ，ＸｉｅＹｏｕｃｈａｎ...

关键词： toluene methylation monolayer dispersion surface acidity threshold effect para selectivity

H_2S对NiW/Al_2O_3和CoMo/Al_2O_3上二苯并噻吩和4,6-二甲基二苯并噻吩加氢脱硫反应的影响

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催化学报 2005年第5期26卷 399-402页

作者：王倩聂红龙湘云中国石油化工股份有限公司石油化工科学研究院北京100083

考察了H2 S对NiW /Al2 O3 和CoMo/Al2 O3 上二苯并噻吩(DBT)和4 ,6 二甲基二苯并噻吩(DMDBT)加氢脱硫反应的影响.结果表明,H2 S同时抑制DBT和DMDBT两种硫化物的加氢脱硫反应,并且对DBT的抑制作用更为明显.对于NiW /Al2 O3 和CoMo/Al2 ... 详细信息

考察了H2 S对NiW /Al2 O3 和CoMo/Al2 O3 上二苯并噻吩(DBT)和4 ,6 二甲基二苯并噻吩(DMDBT)加氢脱硫反应的影响.结果表明,H2 S同时抑制DBT和DMDBT两种硫化物的加氢脱硫反应,并且对DBT的抑制作用更为明显.对于NiW /Al2 O3 和CoMo/Al2 O3 两种催化剂,H2 S抑制了DBT和DMDBT的直接脱硫路径活性;对于CoMo/Al2 O3 催化剂上DBT转化中的加氢反应也有抑制作用,但促进了DMDBT转化中加氢反应的进行.NiW/Al2 O3 催化剂更易受H2

关键词：硫化氢镍钨钴钼氧化铝负载型催化剂二苯并噻吩二甲基二苯并噻吩加氢脱硫

A Catalog of ^(13)CO Clumps from the MWISP in l=10°–20°

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Research in Astronomy and Astrophysics 2024年第5期24卷 218-234页

作者： Xiaoyu Luo Sheng Zheng Zhibo Jiang Zhiwei Chen Yao Huang Shuguang Zeng xiangyun Zeng Rui Zhang Chen long Guangrong Zhou Jinbo Hu Center for Astronomy and Space Sciences China Three Gorges UniversityYichang 443000China College of Electrical Engineering and New Energy China Three Gorges UniversityYichang 443000China College of Science China Three Gorges UniversityYichang 443000China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China

In this study, we present a catalog of molecular clumps extracted from ^(13)CO(J=1-0) emission data of the Milky Way Imaging Scroll Painting(MWISP) project. The data covers the inner Milky Way within the longitude range10°≤l≤20° and the latitude strip of |b|≤ 5°. 25. The workflow for the extraction of clumps, namely Facet-SS-3DClump, consists of two parts: the identification of clump candidates and their verification. First, Facet-SS-3DClump employs FacetClumps to identify clump candidates. Subsequently, high-confidence clumps are obtained by cross-matching with the clumps detected by other algorithms, such as dendrogram. Second, these high-confidence clumps are used as prior knowledge to train a semi-supervised deep clustering approach, SS-3D-Clump, which is applied to verify clump candidates detected by FacetClumps, providing confidence levels for the molecular clumps. Finally, the catalog comprising 18,757 molecular clumps was obtained using Facet-SS-3D-Clump, and the catalog is 90% complete above 37 K km s^(-1). We observe a significant deviation of the mean Galactic latitude for clumps within |b|≤ 2° from the midplane, with b=-0°.110. We found that 82.3% of the dust clumps correspond to ^(13)CO clumps by matching with Herschel infrared dust clumps. In the future, Facet-SS-3D-Clump will be applied to detect ^(13)CO clumps in the entire MWISP data.

关键词： ISM molecules methods data analysis-stars formation