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A chaos genetic algorithm for optimizing an artificial neural network of predicting silicon content in hot metal

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Journal of university of science and Technology beijing 2003年第2期10卷 68-71页

作者： Deling Zheng, Ruixin Liang, ying Zhou, and ying WangInformation engineering {3., university of science and Technology beijing, beijing 100083. china Information engineering school University of Science and Technology Beijing Beijing 100083 China

A genetic algorithm based on the nested intervals chaos search (NICGA) hasbeen given. Because the nested intervals chaos search is introduced into the NICGA to initialize thepopulation and to lead the evolution of the population, the NICGA has the advantages of decreasingthe population size, enhancing the local search ability, and improving the computational efficiencyand optimization precision. In a multi4ayer feed forward neural network model for predicting thesilicon content in hot metal, the NICGA was used to optimize the connection weights and thresholdvalues of the neural network to improve the prediction precision. The application results show thatthe precision of predicting the silicon content has been increased.

关键词： blast furnace optimization chaos genetic algorithm neural network silicon content prediction

Relationship between Low Temperature Toughness and Microstructure in Low Activation Fe-Cr-Mn(W,V)Steel for Fusion Reactors

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International Journal of Minerals,Metallurgy and Materials 1999年第2期13卷 111-115页

作者： Benfu Hu Chengchang jia(Material science and engineering school, {3. of science and Technology beijing, beijing 100083. china) Material science and engineering school University of Science and Technology Beijing Beijing 100083 China

Fe-Cr-Mn (W, V) austenite steel was researched in order to supply a theory base for the first wall materials of fusion *** included vacuum melting, forging, annealing, solution treatment, Charpy impact tests and microstructure observation. Theresults show that the imped value decreases with the test temperature decreasing. In this system, there is ductile/brittle transition. Themechanism of this decrease of the impact value is considered to be due to γ - ε transformation in sub-stable austenite steel and stoppingoverlapping sacking fault by grain boundaries in stable austenite steel.

关键词： fusion reactor first wall materials low temperature toughness Fe-Cr-Mn system

Thermodynamic properties and mixing thermodynamic parameters of binary homogeneous metallic melts

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Rare Metals 2003年第1期22卷 25-32页

作者： ZHANG ManMetallurgical engineering school, university of {3. and Technology beijing, beijing 100083. china Metallurgical engineering school University of Science and Technology Beijing 北京 100083

After the investigation on the thermodynamic properties and mixingthermodynamic parameters of binary homogeneous metallic melts involving compound, peritectic as wellas solid solution, it was found that the equations of mixing free energy DELTA G^m and excess freeenergy DELTA G^(XS) of them can he expressed by the following equations: DELTA G^m = SIGMA x [SIGMAN_i DELTA G_I^(THETA) + RT(SIGMA N_j ln N_j + SIGMA N_i ln N_i )] and DELTA G^(XS) = DELTA G^m -RT(a ln a + b ln b), respectively.

关键词： metallic melt mixing thermodynamic parameter coexistence theory activity mass action concentration

Phenomenological Modeling of Warm Compaction and Experimental Verification

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International Journal of Minerals,Metallurgy and Materials 2000年第4期14卷 292-295页

作者： Shiju Guo, Tao Lin (Material science and engineering school, {3. of science and Technology beijing, beijing 100083. china) Material science and engineering school University of Science and Technology Beijing Beijing 100083 China

A phenomenological modeling approach to establishing the warm compaction equation and curves by modifying the regression equation of the room-temperature compaction curve is presented. An enhanced factor of compacting pressure is introduced into the equation in order to reveal the effects of powder/die temperature and filling height of powders on green density. Compaction curves yielded from this equation are consistent with the experimental data of ATOMET grade iron powders. The curves show that the powder/ die temperature should reduce as the filling heights of powders increase and that in some cases warm compaction can not give rise to a higher green density.

关键词： powder metallurgy warm compaction compaction equation Materials

Dislocation Densites of Deformed Steel Sheets Based on Positron Annihilation

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International Journal of Minerals,Metallurgy and Materials 1998年第1期12卷 47-50页

作者： Yonglin Kang Xianjin Wang (Materials science and engineering school, {3. of science and Technology beijing, beijing 100083. china) Materials science and engineering school University of Science and Technology Beijing Beijing 100083 China

The variation regularity of dislocation densites of some deformed steel sheets under three kinds of strainpaths as uniaxial tension, plane strain and equal biaxial stretching was investigated by means of positron lifetimespectrum and Doppler-broadening techniques. The results show that the increasing rate of dislocation densites isrelated to the plastic strain path. A relationship between the increasing rate of micro-defects, macro-instability andforming limits during the process of steel sheet forming was got based on analyzing the mechanism of dislocationdensity increasing under different stress-strain condihons.

关键词： positron annihilation dislocation steel sheet strain path

Annealing Texture Evolution of Ti-IF Steel during Batch Annealing

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International Journal of Minerals,Metallurgy and Materials 1998年第3期12卷 175-179页

作者： Jing Shi Xianjin Wang(Material science and engineering school, {3. of science and Technology beijing, beijing 100083. china) Material science and engineering school University of Science and Technology Beijing Beijing 100083 China

Texture development and recrystallization behavior of Ti-IF steel during Batch Annealing (BA) were investigared with X-ray diffraction and EBSP in lab, and the results were compared with research work on continu ous annealing (CA) with rapid heating rate. The basic tendencies are similar that eary nucleation takes place in ND fibers, RD fibers are consumed at the end of recrystallization, and ND texture dominates over annealing texture. However, the detailed texture transformation during batch annealing is different and somewhat more compicated than tha in rapid-heating process. Moreover, misorientation plays an important role in texture transformation of BA In addition, the results of EBSP are consistent with that of ODF well.

关键词： Ti-IF steel texture batch annealing X-ray diffraction EBSP

Sol-gel Preparation and Infrared Radiation Property of Boron-substituted Cordierite Glass-ceramics

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Journal of Materials science & Technology 2010年第5期26卷 445-448页

作者： Shuming Wang and Fenghua Kuang school of Materials science and engineering,{3. of science & Technology beijing,beijing 100083.china [a] school of Materials science and engineering university of science & Technology beijing beijing 100083 china

Boron for aluminum substitution in the cordierite structure has been examined by sol-gel preparation of different samples along the compositional junction Mg2Al4-xBxSi5O18 with x=0,0.5,1,*** increasing the x value from 0 to 1.5 the crystallization behavior changed *** amount B2O3.doping can promote the sintering of amorphous cordierite gel,effectively restrain the precipitation of μ-cordierite and enhance the crystallization of α-*** substitution of B3. for Al3. in cordierite crystal structure can effectively improve the near-infrared spectral emissivity of this cordierite based glass-ceramics.

关键词： Sol-gel Glass-ceramics Infrared radiation B3. substitution Solid solution

Prediction of Rock Burst with Deep Mining Excavation in Linglong Gold Mine

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Journal of university of science and Technology beijing 2001年第4期8卷 241-243页

作者： Meifeng Cai, Jinan Wang, Shuanghong Wang Civil and Environmental engineering school, university of {3. and Technology beijing, beijing 100083. china Univ Sci & Technol beijing Sch Civil & Environm Engn Beijing 100083 Peoples R China

To predict rock burst in deep mining excavation in Linglong gold mine, systematical laboratory tests of mechanical properties of rock, in situ stress measurement and 3.D FEM analysis on energy distribution in rock mass surrounding deep mining rooms were carried out. According to various prediction criteria of rock burst, it is concluded that rock burst is liable to occur during deep mining excavation in the mine.

关键词： rock burst prediction deep mining excavation Linglong gold mine

A WT-STFT combining Algorithm

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International Journal of Minerals,Metallurgy and Materials 2000年第4期14卷 315-317页

作者： Xisheng Li, Shaochun Wang (Information engineering school, university of {3. and Technology beijing, beijing 100083. china) Information engineering school University of Science and Technology Beijing Beijing 100083 China

A fast wavelet packet (WP) algorithm is presented, in which the wavelet transform (WT) and the short-time Fourier transform (STFT) are combined. As WT produces multiresolution of frequency and time, and STFT has a fas... 详细信息

关键词： signal processing, wavelet transform short-time Fourier transform Informatid