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Calculating Model of Mass Action Concentrations for Mn-C Melts and Optimization of Thermodynamic Parameters

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International Journal of Minerals,Metallurgy and Materials 1998年第4期12卷 208-211页

作者： Jian Zhang(Metallurgy School, university of science and technology Beijing, Beijing 100083, China) Metallurgy School University of Science and Technology Beijing Beijing 100083 China

Based on the phase diagram, the coexistence theory of the metallic melt structure involving compoundformation and the regularity of melts containing saturated phase, a calculating model of mass action concentrationsfor Mn-C melts was formulated. According to the activities (or activity coefficients AM. and γc.), obtained by theUnified Interaction Parameter Model (UIPM), the thermodynamic parameters G and G at higher temperatures (1628～1873 K) were optimized by the repeated try and error method. It is testified that G G(873～1273 K) and G (298～1623 K), obtained at lower temperatures, can also be used at the above-mentionedhigher temperatures. The calculated N. and N agree well with ac. and ac obtained by UIPM. This result showsthat the deduced model can reflect the structural reality of Mn-C melts.

关键词： Mn-C melts activity coexistence theory mass action concentration

Calculating Models of Mass Action Concentrations for Ni-Mn and Co-Mn Melts and Optimization of Their Thermodynamic Parameters

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International Journal of Minerals,Metallurgy and Materials 2000年第4期14卷 246-250页

作者： Jian Zhang (Metallurgy School, university of science and technology Beijing, Beijing 100083, China) Metallurgy School University of Science and Technology Beijing Beijing 100083 China

According to phase diagrams, measured activities as well as the coexistence theory of motallic melts structure involving compound formation, the calculating models of mass action concentrations for Ni-Mn and Co-Mn melts are formulated and their thermodynamic parameters are optimized. As a result, the calculated mass action concentrations agree well with the corresponding measured activities, showing that these models can reflect the structural characteristics of both Ni-Mn and Co-Mn melts.

关键词： activity metallic melts coexistence theory mass action concentration

Quasi-physical global optimization method for solving the equal circle packing problem

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science China(Information sciences) 2011年第7期54卷 1333-1339页

作者： HUANG WenQi & YE Tao School of Computer science and technology,Huazhong university of science and technology,Wuhan 430074,China School of Computer science and technology Huazhong University of Science and Technology Wuhan China

The equal circle packing problem is a well-known challenge in *** is also a natural,clear and fair test system for global *** paper presents a quasi-physical global optimization algorithm for solving the equal circle packing *** algorithm simulates two kinds of movements of N elastic disks: smooth movement driven by elastic pressures and violent movement driven by strong repulsive forces and attractive *** smooth movement makes the disks reach a locally optimal configuration,while the violent movement makes them jump out of the local optimum trap and reach a more promising *** algorithm is tested on the widely studied instances of N = 1,2,...,*** find better packings than the reported best-known ones on 37 instances and reproduce the best-known results on the remaining 113 instances.

关键词： equal circle packing global optimization quasi-physical method heuristic

THE GROWTH THEOREM FOR STARLIKE MAPPINGS ON BOUNDED STARLIKE CIRCULAR DOMAINS

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Chinese Annals of Mathematics,Series B 1998年第4期19卷 401-408页

作者： LIU TAISHUN (Department of Mathematics, university of science and technology of China, Hefei 230026, China)REN GUANGBIN (Department of Mathematics, university of science and technology of China, Hefei 230026, China) Department of Mathematics University of Science and Technology of China Hefei 230026 China

The authors obtain the growth and covering theorem for the class of normalized biholomorphic starlike mappings on bounded starlike circular *** type of domain discussed is rather general, since the domain must be starlike if there exists a normalized biholomorphic starlike mapping on it. In the unit disc, it is just the famous growth and covering theorem for univalent *** theorem successfully realizes the initial idea of H. Cartan about how to extend geometric function theory from one variable to several complex variables.

关键词： Starlike mappings Growth theorem Starlike circular domains

FORMING PRINCIPLE OF TWO SIDE-DIRECTION BURR AND IT'S PREDICTION IN METAL CUTTING

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Chinese Journal of Mechanical Engineering 2001年第4期14卷 300-304页

作者： Wang Guicheng (School of Machinery Engineering,Jiangsu university of science and technology) 江苏理工大学江苏

The burr is one of the common phenomena occurring i n metal cutting operations The mathematical mechanical model of two side dir ection burr formation and transformation is established with plane stress strain theory,based on the orthogonal cutting The main laws of formation and change of the burr are revealed,and it is confirmed by experiment result,which first realizes prediction of the forming and changing of the two side direction burr in metal cutting operation.

关键词： Metal cutting Two side direction burr Mathe matical mechanical model Prediction Precision and ultraprecision machining

Calculating Models of Mass Action Concentrations for Fe-P and Cr-P Melts and Optimization of Their Thermodynamic Parameters

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International Journal of Minerals,Metallurgy and Materials 1999年第3期13卷 174-177页

作者： Jian Zhang(Metallurgy School, university of science and technology Beijing, Beijing 100083, China) Metallurgy School University of Science and Technology Beijing Beijing 100083 China

Based on the phase diagrams, reliable reference experimental data and the coexistence theory of metallic melts structure involving compound formation, calculating models of mass action concentrations for Fe-P and Cr-P melts have been formulated. At the same time, some of their thermodynamic parameters have been optimized. The calculated results not only agree well with the measuredvalues, but also obey the mass action law rigorously, this in turn shows that these models can reflect the structural characteristics of corresponding melts.

关键词： activity phase diagram coexistence theory mass action concentration

Mine laneway 3D reconstruction based on photogrammetry

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中国有色金属学会会刊：英文版 2011年第S3期21卷 686-691页

作者： ZHANG Chun-sen College of Geomatics, Xi’an university of science and technology, Xi’an 710054, China College of Geomatics Xi'an University of Science and Technology Xi'an 710054 China

Aiming at the problem of 3D reconstruction for mine laneway, the technique route and step were given based on digital close range photogrammetry and traverse surveying. 3D coordinates of laneway traverse point, photogrammetric station, control strip points were obtained by electronic total station based on mine coordinate system. The feature points were extracted from the scene images. The camera was calibrated by direct linear transformation (DLT). 3D relative coordinates of the arbitrary feature points in mine laneway were calculated after feature points being matched, in which the origin of coordinate system is photogrammetric station. The 3D absolute coordinates of the feature points in mine laneway can be obtained by the combined adjustment of photogrammetry and non-photogrammetric observations and coordinate conversion. The measurable 3D model of the underground laneway terrain surface was constructed with the 3D coordinates of feature points on the image pairs obtained. The measurable 3D model of a corridor was reconstructed by the mentioned method and the experiment precision with an average standard deviation of 0.013 6 m between the 3D model and practical measure was obtained by electronic total station. The experimental resulted show the validity of the proposed approach.

关键词： digital mine mine laneway photogrammetry 3D reconstruction direct linear transformation (DLT)

MECHANISM FOR DIFFUSION OF BORON IN γ-Fe

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Acta Metallurgica Sinica(English Letters) 1992年第5期5卷 318-323页

作者： YU Zongsen CHEN Ning university of science and technology Beijing,Beijing,China Beijing Univ of science and Technology Beijing China

Mechanism for diffusion of B in γ-Fe is believed to be mainly by means of boron-vacancy complexes other than as interstitial atoms *** was made of calculation on the ba- sis of theoretical model proposed by the *** calculated diffusion coefficient of B in γ-Fe after this mechanism is consistent with the experimental *** addition,this is also supported by the non-equilibrium segregation phenomenon of B at grain boundaries of γ-Fe and the lattice constant measurement of Fe-B alloy.

关键词： boron vacancy diffusion non-equilibrium segregation γ-Fe

Calculating Model of Mass Action Concentrations for Fe-Cr-P Melts and Optimization of Thermodynamic Parameters

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 11-14页

作者： Jian Zhang (Metallurgy School, university of science and technology Beliing, Beijing 100083, China) Metallurgy School University of Science and Technology Beijing Beijing 100083 China

According to the results of research on the thermodynamic propelles of Fe-Cr, Fe-P and Cr-P melts, the measured achvihes of Fe-Cr-P melts from reference sources as well as the coexistence theory of metallic melts structure involving compound formation, a calculating model of the mass action concentrations for Fe-Cr-P melts has been formulated and some of its thermodynamic parameters have been optimized. The calculated mass action concentrations agree with the measured achvities, which shows that this model can reflect the structural reality of Fe-Cr-P melts.

关键词： activity dephosphorization of stainless steel, coexistence theory mass action concentration