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铸造系统热应力有限元法适应性分析

天津理工学院学报 1999年第3期15卷 75-79页

作者：张瑞红张敬宇刘兴业天津理工学院机械系天津300191 天津大学天津30072

本文以块平衡恢复方法对铸造系统凝固过程中的热应力进行误差估计，并适应性化分网格．方法简单，收敛性较好，

关键词：误差估计铸造系统适应性分析热应力有限元

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对气测录井烃组分三角形图解法的研究

天津理工学院学报 2004年第2期20卷 30-33页

作者：何宏童锡骏安源天津理工学院光电信息与电子工程系天津行政学院计算机系天津300380

气测录井是通过分析钻井液中石油和天然气中的烃类气体、氢气、二氧化碳气体来发现和评价油气层的技术.三角形图解法是评价油气层的方法之一,本文用数学分析的方法得出了与三角形图解法相关的关系式,将繁琐、不精确的做图法换成简单的运... 详细信息

气测录井是通过分析钻井液中石油和天然气中的烃类气体、氢气、二氧化碳气体来发现和评价油气层的技术.三角形图解法是评价油气层的方法之一,本文用数学分析的方法得出了与三角形图解法相关的关系式,将繁琐、不精确的做图法换成简单的运算,不仅改进了工作方法,而且极大地提高了精度.

关键词：气测录井三角形图解法烃组分数学分析

On the composition operators on the Bloch space of several complex variables

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Science china Mathematics 2005年第Z1期48卷 392-399页

作者： ZHOU Zehua & CHE Renyu Department of Mathematics, tianjin University, tianjin 300072, china LiuHui Center for Applied Mathematics, Nankai University & tianjin University,tianjin 300072, china Department of Mathematics Tianjin University Tianjin China LiuHui Center for Applied Mathematics Nankai University & Tianjin University Tianjin China

In this paper we first look upon some known results on the composition operator as bounded or compact on the Bloch-type space in polydisk and ball, and then give a sufficient and necessary condition for the compositio... 详细信息

关键词： Bloch space, bounded symmetric domains, composition operator, bergman metric.

Corrosion science general-purpose data model and interface (Ⅱ): OOD design and corrosion data markup language (CDML)

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Science china(Technological Sciences) 2008年第11期51卷 1850-1857页

作者： TANG ZiLong School of Materials Science and Engineering, tianjin University, tianjin 300072, china School of Materials Science and Engineering Tianjin University Tianjin China

With object oriented design/analysis, a general purpose corrosion data model (GPCDM) and a corrosion data markup language (CDML) are created to meet the increasing demand of multi-source corrosion data integration and sharing. "Cor- rosion data island" is proposed to model the corrosion data of comprehensiveness and self-contained. The island of tree-liked structure contains six first-level child nodes to characterize every important aspect of the corrosion data. Each first-level node holds more child nodes recursively as data containers. The design of data structure inside the island is intended to decrease the learning curve and break the acceptance barrier of GPCDM and CDML. A detailed explanation about the role and meaning of the first-level nodes are presented with examples chosen carefully in order to review the design goals and requirements proposed in the previous paper. Then, CDML tag structure and CDML application programming interface (API) are introduced in logic order. At the end, the roles of GPCDM, CDML and its API in the multi-source corrosion data integration and information sharing are highlighted and projected.

关键词： corrosion data model corrosion data markup language (CDML) application programming interface (API) information sharing

Corrosion science general-purpose data model and interface (Ⅲ):Data integration and management environment

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Science china(Technological Sciences) 2008年第12期51卷 2089-2094页

作者： TANG ZiLong School of Materials Science and Engineering,tianjin University,tianjin 300072,china School of Materials Science and Engineering Tianjin University Tianjin China

A brand new Corrosion Data Integration and Management Environment(CDIME) is developed in Java programming language based on general-purpose corrosion data model(GPCDM) and corrosion data markup language(CDML) proposed in the previous *** general,the functionalities and features of CDIME meet most of design requirements including composition,inheritance,self-contained,relatively independence and so *** insight tutorial is introduced on the life circle of corrosion data islands from its creation,maintenance,and application like *** template feature makes the building of comprehensive data island as simple as a few mouse ***-only publishing of data as e-Book and PDF hold their own *** document can be imported and exported freely on any running *** achieving feature is addressed in detail because it is critical to data sharing and integration in *** the end,a real example is presented to help the understanding of data islands assembling and the advanced features offered by CDIME.

关键词： corrosion software data model information integration

Wave-packet method for instability of three-dimensionalboundary layer of swept wing

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Chinese Science Bulletin 1998年第6期43卷 461-464页

作者： ZHAO Gengfu Department of Physics, tianjin University, tianjin 300072, china Department of Physics Tianjin University Tianjin China

A wave-packet method is proposed to study evolution the behavior of disturbances in 3-D boundary layer on a swept plate. It is proved that the constant-phase lines are equivalent to the streaks observed in flow-visual... 详细信息

关键词： swept plate wave packet structure of streaks.

Second mode unstable disturbance measurement of hypersonic boundary layer on cone by wavelet transform

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Acta Mechanica Sinica 2011年第4期27卷 488-493页

作者： Jian Han.Nan Jiang.Yan Tian Department of Mathematics,tianjin University,300072 tianjin,china Department of Mechanics,tianjin University,300072 tianjin,china tianjin Key Laboratory of Modern Engineering Mechanics,300072 tianjin,china State Key Laboratory of Nonlinear Mechanics,Institute of Mechanics,Chinese Academy of Sciences,100190 Beijing,china Department of Mathematics Tianjin University Tianjin China Department of Mechanics Tianjin University Tianjin China tianjin Key Laboratory of Modern Engineering Mechanics Tianjin China State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing China

Experimental investigation of hypersonic boundary layer instability on a cone is performed at Mach number 6 in a hypersonic wind tunnel. Time series signals of instantaneous fluctuating surface-thermal-flux are measured by Pt-thin-film thermocouple temperature sensors mounted at 28 stations on the cone surface in the streamwise direction to investigate the development of the unstable disturbance. Wavelet transform is employed as a mathematical tool to obtain the multi-scale characteristics of fluctuating surfacethermal-flux both in the temporal and spectrum space. The conditional sampling algorithm using wavelet coefficient as an index is put forward to extract the unstable disturbance waveform from the fluctuating surface-thermal-flux *** generic waveform for the second mode unstable disturbance is obtained by a phase-averaging technique. The development of the unstable disturbance in the streamwise direction is assessed both in the temporal and spectrum space. Our study shows that the local unstable disturbance detection method based on wavelet transformation offers an alternative powerful tool in studying the hypersonic unstable mode of laminar-turbulent transition. It is demonstrated that, at hypersonic speeds, the dominant flow instability is the second mode, which governs the course of laminar-turbulent transition of sharp cone boundary layer.

关键词： Hypersonic boundary layer. Sharp cone Insta-bility Wavelet transform

Corrosion science general-purpose data model and interface (I): Meanings and issues of design and implementation

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Science china(Technological Sciences) 2008年第9期51卷 1394-1401页

作者： TANG ZiLong School of Materials Science and Engineering, tianjin University, tianjin 300072, china School of Materials Science and Engineering Tianjin University

A brand new design of integrated corrosion information system is introduced to meet the constantly increasing demands of material corrosion information. Two concepts, "general-purpose corrosion data model" and "public corrosion data ex-changing interface", are suggested to integrate a wide variety of corrosion data sources based on detailed analysis on characteristics of each source in order to promote the information sharing and data mining. The architecture of integrated corrosion information environment is blueprinted. The insight analysis is focused on 1) architecture of the system; 2) data flow and information sharing; 3) roles of system players and their interactions; 4) approaches to data integration. Several key issues are addressed in detail including coverage of data model, data source integration and mitigation, and data granularity from system performance and model acceptance points of view. At the end, the design and implementation ap-proach of general corrosion data model is presented based on cutting edge IT techniques.

关键词： corrosion multi-source data modeling integrated information system

Inflow conditions for spatial direct numerical simulation of turbulent boundary layers

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Science china(Physics,Mechanics & Astronomy) 2008年第8期51卷 1106-1115页

作者： HUANG ZhangFeng & ZHOU Heng Department of Mechanics,tianjin University,tianjin 300072,china Liu-Hui Center of Applied Mathematics,Nankai University and tianjin University,tianjin 300072,china Department of Mechanics Tianjin University Tianjin China Liu-Hui Center of Applied Mathematics Nankai University and Tianjin University Tianjin China

The inflow conditions for spatial direct numerical simulation(SDNS) of turbulent boundary layers should reflect the characteristics of upstream turbulence,which is a puzzle. In this paper a new method is suggested,in which the flow field obtained by using temporal direct numerical simulation(TDNS) for fully developed turbulent flow(only flow field for a single moment is sufficient) can be used as the inflow of SDNS with a proper transformation. The calculation results confirm that this method is feasible and effective. It is also found that,under a proper time-space transformation,all statistics of the fully developed turbulence obtained by both temporal mode and spatial mode DNS are in excellent agreement with each other,not only qualitatively,but also quantitatively. The normal-wise distributions of mean flow profile,turbulent Mach number and the root mean square(RMS) of the fluctuations of various variables,as well as the Reynolds stresses of the fully developed turbulence obtained by using SDNS,bear similarity in nature.

关键词： inflow conditions spatial direct numerical simulation turbulent boundary layer similarity