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The calculating model of Structural Analysis for Jack-Up Rig Legs

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China Ocean Engineering 1993年第4期8卷 409-416页

作者： Gu Guowei and Huang Youqing Senier Engineer, China Ofishore Oil Development & Engineering Corporation, (CNOOC), Zhanajiang 524057 China Offshore Oil Development & Engineering Corporation, (CNOOC), Zhanajiang 524057

The selection or establishment of structural calculating model is a matter of primary importance in structural analysis. By analysing the irrationality of the calculating models used by some research organizations at home and abroad in structural analyses for truss jack-up rig legs, this paper introduces a new calculation model which is more reasonable. This model can simulate better the load situation of a rig reflecting more precisely the effects of the leg loads caused by the spring support of gearboxes of the jacking system and the secondary bending moment raised by hull displacement under extreme conditions. The rig conversion was completed in 1989. In July 1991 the rig safely stood the frontal hitting of Typhoon with the wind speed of 52 m / s, which shows that the checking on the structure is correct.

关键词： jack-up leg conversion calculating model platform

calculating models on surface tension of RE_2O_3-Mg O-SiO_2(RE=La, Nd, Sm, Gd and Y) melts

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Transactions of Nonferrous Metals Society of China 2014年第11期24卷 3696-3701页

作者：吴铖川成国光北京科技大学钢铁冶金新技术国家重点实验室北京100083

A thermodynamic model was developed for determining the surface tension of RE2O3-MgO-SiO2(RE=La, Nd, Sm, Gd and Y) melts considering the ionic radii of the components and Butler's equation. The temperature and composition dependence of the surface tensions in molten RE2O3-MgO-SiO2 slag systems was reproduced by the present model using surface tensions and molar volumes of pure oxides, as well as the anionic and cationic radii of the melt components. The iso-surface tension lines of La2O3-MgO-SiO2 slag melt at 1873 K were calculated and the effects of slag composition on the surface tension were also investigated. The surface tensions of La2O3, Gd2O3, Nd2O3 and Y2O3 at 1873 K were evaluated as 686, 677, 664 and 541 m N/m, respectively. The surface tension of pure rare earth oxide melts linearly decreases with increasing cationic field strength, except for Y2O3 oxide, while Y2O3 has a much weaker surface tension. The evaluated results of the surface tension show good agreements with literature data, and the mean deviation of the present model is found to be 1.05% at 1873 K.

关键词： rare-earth oxide surface tension ionic radius Butler's equation calculating model

Structure and property of metal melt Ⅳ——Evolution of titanium melt residual bond structure and its effect on dynamic viscosity

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Science China(Physics,Mechanics & Astronomy) 2012年第8期55卷 1371-1375页

作者： MI GuangBao CAO JingXia HUANG Xu CAO ChunXiao LIPeiJie HE LiangJu Aviation Key Laboratory of Science and Technology on Advanced Titanium Alloys Beijing Institute of Aeronautical Materials Beijing 100095 China National Center afNovel Materials for International Research Tsinghua University Beijing 100084 China

Based on the concept of melt residual bonds, a calculating model quantitatively describing the evolution of the residual bond structure of titanium melt at the melting point or in a certain range above the melting point was established; i.e., both the size ds and the bond number n of the residual bond structure decrease monotonously with the increase of temperature. By mathe- matical deduction, a linear relationship between the residual bond structure size ds and the dynamic viscosity 17 of Titanium melt was revealed, i.e., η= 0.876 ＋ 0.471·ds, which is of great significance to the investigation of the relationship between the melt microstructure and the macroscopic properties of metals with high melting temperature.

关键词： titanium melt residual bond structure dynamic viscosity calculating model

The Calculation model for Operation Cost of Coal Resources Development Based on ANN

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Journal of China University of Mining and Technology 2004年第1期14卷 98-103页

作者：刘海滨 School of Management CUMT Beijing 100083 China

On the basis of analysis and selection of factors influencing operation cost of coal resources development, fuzzy set method and artificial neural network (ANN) were adopted to set up the classification analysis model of coal resources. The collected samples were classified by using this model. Meanwhile, the pattern recognition model for classifying of the coal resources was built according to the factors influencing operation cost. Based on the results achieved above, in the light of the theory of information diffusion, the calculation model for operation cost of coal resources development has been presented and applied in practice, showing that these models are reasonable.

关键词： operating cost artificial neural network (ANN) calculating model

Evolution of Titanium Melt Residual-Bond Structure and Its Effect on Dynamic Viscosity

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Evolution of Titanium Melt Residual-Bond Structure and Its E...