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Iterative identification of discrete-time output-error model with time delay

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Journal of Central South University 2017年第3期24卷 647-654页

作者： CHEN feng-wei LIU Tao School of Cortrol Science and Engineering Dalian University of Technology Dalian 116024 China

The problem of discrete-time model identification of industrial processes with time delay was *** iterative and separable method is proposed to solve this problem,that is,the rational transfer function model parameters and time delay are alternately fixed to estimate each *** instrumental variable technique is applied to guarantee consistent estimation against measurement noise.A noteworthy merit of the proposed method is that it can handle fractional time delay estimation,compared to existing methods commonly assuming that the time delay is an integer multiple of the sampling *** identifiability analysis for time delay is addressed and correspondingly,some guidelines are provided for practical implementation of the proposed *** and experimental examples are presented to illustrate the effectiveness of the proposed method.

关键词： system identification output-error model instrumental variable method time delay

CMP体系下基于历史文脉传承的淮安城市遗产价值评估

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华中建筑 2025年第1期43卷 12-17页

作者：单超杨芮冯靖茹苏州大学建筑学院历史建筑保护工程所苏州大学建筑学院东南大学建筑学院

淮安,中国大运河线上最重要的水利枢纽城市之一。自元明清三朝定都北京,大运河重新疏浚、改线、贯通后,北方巨量的物资需求促使漕运兴盛,时值淮安城扼漕运、盐运、河工、榷关、邮驿之机杼,风光一时无两。现下,运河城市遗产的保护传承利... 详细信息

淮安,中国大运河线上最重要的水利枢纽城市之一。自元明清三朝定都北京,大运河重新疏浚、改线、贯通后,北方巨量的物资需求促使漕运兴盛,时值淮安城扼漕运、盐运、河工、榷关、邮驿之机杼,风光一时无两。现下,运河城市遗产的保护传承利用逐渐成为城市发展中的重要部分,淮安城市遗产反映着其城市文化特征,也是城市职能的直接体现。该文利用CMP(保护规划管理)从场所意义出发,对淮安城市遗产进行价值评估,并试图以此构建基于历史文脉保护利用传承导则,助推大运河文化带建设。

关键词：历史文脉淮安 CMP 城市遗产价值评估

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X射线测量高速钢上不同厚度氮化钛涂层残余应力

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材料科学与工艺 2010年第3期18卷 415-419,424页

作者：弓满锋乔生儒卢国锋姬浩西北工业大学超高温结构复合材料国家重点实验室陕西西安710072 湛江师范学院机电工程系广东湛江524048

采用多弧离子镀在AISIM2高速钢(HSS)上沉积了TiN硬涂层,试样中基体厚度为1mm,涂层厚度分别为3.0、5.0、7.0、9.0和11.0μm.应用X射线衍射(XRD)分析了TiN涂层中残余应力,测量了TiN(220)衍射晶面在五种不同倾斜角(Ψ=0°,20.7°,30°,37.... 详细信息

采用多弧离子镀在AISIM2高速钢(HSS)上沉积了TiN硬涂层,试样中基体厚度为1mm,涂层厚度分别为3.0、5.0、7.0、9.0和11.0μm.应用X射线衍射(XRD)分析了TiN涂层中残余应力,测量了TiN(220)衍射晶面在五种不同倾斜角(Ψ=0°,20.7°,30°,37.8°和45°)下的X射线衍射峰.结果表明:在3～11μm涂层厚度范围内,TiN涂层中均表现出残余压应力且残余压应力值较大.TiN涂层中残余应力大致分布在-3.22～-2.04GPa之间,本征应力分布在-1.32～-0.14GPa,热应力约为-1.86～-***涂层中残余应力值随涂层厚度变化是非线性增加的,随厚度增加表现出先增大后减小的变化趋势,多项式拟合后发现约在8.5μm厚时残余应力达到最大值.

关键词： TiN涂层多弧离子镀残余应力 XRD 涂层厚度

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紧邻既有结构的深基坑受力变形特性分析

上海交通大学学报 2016年第10期50卷 1658-1664页

作者：陈树林张峰代楠山东省建筑科学研究院济南250031 泰安市工程质量检测中心泰安271000

基于考虑土体排水条件的摩尔库伦本构模型,采用有限差分软件FLAC3D建立准三维数值模型,模拟了有无邻近地下结构的基坑开挖过程并进行对比分析,得到了邻近地下结构深基坑的围护结构的受力变形特性.进一步研究了基坑围护结构土压力分布和... 详细信息

基于考虑土体排水条件的摩尔库伦本构模型,采用有限差分软件FLAC3D建立准三维数值模型,模拟了有无邻近地下结构的基坑开挖过程并进行对比分析,得到了邻近地下结构深基坑的围护结构的受力变形特性.进一步研究了基坑围护结构土压力分布和水平位移与基坑和地下结构间距的关系,揭示了地下结构对邻近基坑围护结构受力变形影响的机理.结果表明,地下结构使坑间土体产生土拱效应而减小邻近基坑围护结构的变形;围护结构最大水平位移随着坑间距减小呈非线性减小;间距的变化会影响坑内外土体的变形受力;既有地下结构与邻近基坑的临界间距为1.5倍开挖深度.

关键词：基坑开挖地下结构围护结构临界间距主动土压力

Investigation of Aconitine-type Alkaloids from Processed Tuber of Aconitum carmiechaeli by HPLC-ESI-MS/MS^n

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Chemical Research in Chinese Universities 2007年第5期23卷 625-627页

作者： YUE Hao PI Zi-feng ZHAO Yu-feng SONG feng-rui LIU Zhi-qiang LIU Shu-ying Changchun Center of Mass Spectrometry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China Graduate School of the Chinese Academy of Sciences Beijing 100039 P. R. China

Introduction Aconitine-type alkaloids isolated from the roots of Aconitum carmiechaeli show a potential toxicity and a broad spectrum of bioactivity[1-4].On the basis of the C8-substituent of C19-diterpenoid skeleton,aconitine-type alkaloids can be divided into diester-diterpenoid alkaloids（DDAs）,monoester-diterpenoid alkaloids（MDAs）,and lipo-alkaloids（Fig.1）.

关键词： Aconitine-type alkaloids HPLC-ESI-MS/MS^n Aconitum carmiechaeli

Yb^(3+),Tb^(3+)共掺杂Sr_2B_2O_5荧光粉的制备及其下转换发光性能的研究

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无机材料学报 2016年第10期31卷 1081-1086页

作者：戴智刚李友芬李刚杨儒北京化工大学材料电化学过程与技术北京市重点实验室北京100029 北京化工大学碳纤维及功能高分子教育部重点实验室北京100029

采用高温固相法合成了Tb^(3+),Yb^(3+)共掺杂的Sr_2B_2O_5荧光粉。通过X射线衍射(XRD)和荧光光谱(PL)对样品的物相结构和发光性质进行了表征。XRD结果表明,合成样品为单斜结构的Sr_2B_2O_5相。分别使用543 nm和980 nm的监测波长,得到的... 详细信息

采用高温固相法合成了Tb^(3+),Yb^(3+)共掺杂的Sr_2B_2O_5荧光粉。通过X射线衍射(XRD)和荧光光谱(PL)对样品的物相结构和发光性质进行了表征。XRD结果表明,合成样品为单斜结构的Sr_2B_2O_5相。分别使用543 nm和980 nm的监测波长,得到的激发光谱均在354 nm、374 nm处有较强的激发峰,其中374 nm处最强,说明Sr_2B_2O_5荧光材料在近紫外光区对太阳光有很强的吸收;在374 nm(Tb^(3+):~7F_6→~5D_3)紫外光激发下,观察到Tb^(3+):~5D_4→~7F_J(J=6,5,4,3)可见光区发射光,并检测到Yb^(3+):~2F_(5/2)→~2F_(7/2)的近红外发射光。通过研究激发光谱和发射光谱与Yb^(3+)掺杂浓度的关系,发现在单斜晶体Sr_2B_2O_5中,Yb^(3+)具有很高的猝灭浓度。

关键词： Sr2B2O5 Tb^3+ Yb^3+ 下转换发光材料

A REVOLUTIONARY PATH IN TREATMENT OF OTOSCLEROSIS AND ITS RELEVANCE IN CHINA

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Journal of Otology 2012年第2期7卷 75-77页

作者： dai Pu SONG Yueshuai Department of Otolaryngology Head and Neck Surgery Chinese PLA General Hospital Department of Otolaryngology Head and Neck Surgery Chinese PLA General Hospital (Hainan)

Otosclerosis was first discovered by Valsalva in 1704[1], and the term was first used by Anton von Troltsch in 1872 to differentiate from tympanosclerosis[2].Normallythe otic cyst in human remains stationary after ful... 详细信息

关键词： A REVOLUTIONARY PATH IN TREATMENT OF OTOSCLEROSIS AND ITS RELEVANCE IN CHINA

Influence of service temperature on tribological characteristics of self-lubricant coatings： A review

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Frontiers of Materials Science 2013年第1期7卷 28-39页

作者： Jun-feng YANG Yan JIANG Jens HARDELL Braham PRAKASH Qian-feng FANG Key Laboratory of Materials Physics Institute of Solid State Physics Chinese Academy of Sciences Hefei 230031 China Department of Applied Physics and Mechanical Engineering Lulea University of Technology SE-971 87 Lulea Sweden

Self-lubricating coatings have been widely used to reduce friction in moving machine assemblies. However, the tribological performance of these coatings is strongly dependent on the service temperature. In this paper, an extensive review pertaining to the influence of operating service temperature on tribological performance of self-lubricating coatings has been carried out. Based on the effective lubricating temperature range, the self-lubricating coatings developed in the past have been divided into three groups: low temperature lubricant coating (from ?200°C to room temperature), moderate temperature lubricant coating (from room temperature to 500°C) and high temperature lubricant coating (> 500°C). Ideas concerning possible ways to extend the operating temperature range of self-lubricating coatings have been presented as follows: hybridized tribological coating, adaptive tribological coatings, and diffusion rate limited solid lubricant coating. In addition, a new self-lubricating coating formulation for potential application at a wide operating temperature range has been proposed.

关键词： temperature solid lubricant self-lubricating coating tribological property

Change in Sediment Provenance Near the Current Estuary of Yellow River Since the Holocene Transgression

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Journal of Ocean University of China 2018年第3期17卷 535-544页

作者： SONG Sheng feng Xiuli LI Guogang LIU Xiao XIAO Xiao feng Li Key Laboratory of Submarine Geosciences and Prospecting College of Marine Geosciences Ocean University of China Marine Engineering and Prospecting Institute of North China Sea North China Sea Branch of the State Oceanic Administration

Sedimentary sequence and sediment provenance are important factors when it comes to the studies on marine sedimentation. This paper studies grain size distribution, lithological characteristics, major and rare earth elemental compositions, micropaleontological features and ^(14)C ages in order to examine sedimentary sequence and sediment provenance of the core BH6 drilled at the mouth of the Yellow River in Bohai Sea. According to the grain size and the micropaleontological compositions, 4 sedimentary units have been identified. Unit 1(0–8.08 mbsf) is of the delta sedimentary facies, Unit 2(8.08–12.08 mbsf) is of the neritic shelf facies, Unit 3(12.08–23.85 mbsf) is of near-estuary beach-tidal facies, and Unit 4(23.85 mbsf–) is of the continental lake facies. The deposits from Unit 1 to Unit 3 have been found to be marine strata formed after the Holocene transgression at about 10 ka BP, while Unit 4 is continental lacustrine deposit formed before 10 ka BP. The provenances of core BH6 sediments show properties of the continental crust and vary in different sedimentary periods. For Unit 4 sediments, the source regions are dispersed while the main provenance is not clear, although the parent rock characteristics of a few samples are similar to the Luanhe River sediments. For Unit 3, sediments at 21.1–23.85 mbsf have been mainly transported from the Liaohe River, while sediments above 21.1 mbsf are mainly from the Yellow River and partially from the Liaohe River. For Unit 2, the sediments have been mainly transported from the Yellow River, with a small amount from other rivers. For Unit 1, the provenance is mainly the Yellow River catchment. These results help in better understanding the evolution of the Yellow River Delta.

关键词： Yellow River Estuary Holocene transgression rare earth element provenance