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Local segment-shared protection based on source egress gateway selection for multi-domain optical mesh networks

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science China(Information sciences) 2011年第2期54卷 227-235页

作者： ZHANG ShengFeng1,3, PENG YunFeng1,2. DU Shu1, YANG XiaoLong1,2.& LONG KePing1,2.1Research Center for Optical Internet and Mobile Information networks, university of Electronic{2. and technology of China, Chengdu 611731, China 2.nstitute of advanced network technology and new serives (ANTS), university of science and technology beijing, beijing 100083, China 3Research Center for Optical Internet networks, Chongqing university of Posts and Telecommunications, Chongqing 400065, China 1. Research Center for Optical Internet and Mobile Information networks University of Electronic Science and Technology of China Chengdu 611731 China3. Research Center for Optical Internet Networks Chongqing University of Posts and Telecommunications Chongqing 400065 China2. Institute of Advanced Network Technology and New Serives (ANTS) University of Science and Technology Beijing Beijing 100083 China

Survivability for multi-domain optical networks is becoming a key parameter due to expanding network. In order to provide the shared-path-protected lightpath in multi-domain optical mesh networks, we propose a protection solution, called GSLSSP. A new source egress gateway selecting mechanism is adopted in this solution. For each connection request, this mechanism can enable the source node to select a better egress gateway node to the destination domain and compute one inter-domain working path near the optimal path with the cooperating of this gateway node, under scalability and domain privacy constraint of multi-domain networks. And then one intra-domain link-disjoint local segment-backup path for each working-segment path is computed out in each single-domain passed by the working path. Simulation evaluation shows that the proposed scheme can provide 100% protection ability for multiple failures. Besides, it is effective in multi-domain path protection with more efficient resource utilization, lower blocking probabilities and less inter-domain cost than other schemes.

关键词： survivability optical mesh networks multi-domains multiple failures segment-shared protection

MEAM Potential with Angular Dependence for TiAl

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Rare Metals 2001年第1期20卷 13-17页

作者： Xiaodong Ni, Xitao Wang, Guoliang Chen (Physics Department, university of science and technology beijing, beijing 100083, China State Key Laboratory for{2. Metals and Materials, university of science and technology beijing, beijing 100083, China) Univ Sci & Technol beijing Dept Phys Beijing 100083 Peoples R China Univ Sci & Technol beijing State Key Lab Adv Met & Mat Beijing 100083 Peoples R China

The modified embedded atom method (MEAM) is an empirical extension of the embedded atom method (EAM) that includes angular forces. By fitted to the lattice constants, the cohesive energy, the APE (anti-phase boundary) energy, and the vacancy formation energy of TiAl, an accurate MEAM potential is obtained for the TiAl system with L10 structure. The calculation results of the properties of TiAl are in good agreement with experiments and the results of first principle (F.P.) calculations.

关键词： embedded atom method TiAl alloy angular dependence potential intermetallics

Theorems for Testing Local Activity of CNN and Application to Cardiac Purkinje Equations

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International Journal of Minerals,Metallurgy and Materials 2000年第2期14卷 139-146页

作者： Lequan Min(Applied science School, university of science and technology beijing,{2., China) Applied science School University of Science and Technology Beijing Beijing 100083 China

The theorems for testing the local in one-port cellular neural/inear network (CNN) cells with four local state variables are presented. Using the theorems computes the bifurcation diagrams of the cardiac Purkinje fiber (CPE) equations Which describethe long-lasting action and pace-maker potentials of the Purkinje fiber of the heart. The computer simulation shows that periodic trajectories or convergent trajectories of the CPF Equations can be foun if the cormsponing cell Parameters are located in a positive domainbut nearby edge of chaos. In particular a heart with approximate normal frequency of heartbeat but non-normal electrocardiogram maysuddenly stop by slightly perturbing the parameters of the corresponding CPF Equations when the Paramders are located nearby the edge of chaos in the bifurcation diagrams. This research seems to interpret reasonbly the phenomena that patients with cardiac diseases might suddenly die without warning.

关键词： cellular neural network local activity cardiac Purkinje fiber heartbeat

Distribution of Nb atom in the TiAl+Nb system

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Rare Metals 2001年第1期20卷 5-12页

作者： Xiaodong Ni, Xidong Hui, Guoliang Chen (Applied science School, university of science and technology beijing,{2., China State Key Laboratory for advanced Metals and Materials, university of science and technology beijing, China) Appl. Sci. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

Based on MEAM (the modified embedded atom method) potential and an average atom model similar to B-W (Bragg-Williams) method, the distribution of Nb atoms in TiAl+Nb compounds with various composition was calculated. The calculation results showed that Nb atoms prefer to occupy the Ti sublattice of L10 structure for all compounds in question. With increasing atomic fraction of Nb and Al, Nb atoms exhibited a trend of ordered distribution on the Ti sublattice and result in a new L10 derivative superlattice structure.

关键词： Computer simulation Intermetallics Superlattices Ternary systems

Carbon Solubility and Mass Action Concentrations of Fe-Cr-C Melts

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International Journal of Minerals,Metallurgy and Materials 2000年第2期14卷 86-91页

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

An empirical equation of carbon solubility in Fe-Cr-C melts is regressed based on the experimental data from references. Acalculating model of mass action concentrations for these melts is formulated on the basis of the coexistence theory of metaIlic melts in-volving compound formation, the phase diagram of Cr-C system as well as thermodynamic data of Fe-Cr-C melts. According to the mod-el, the standard Gibbs free energies of formation of CrC and Cr3C2.are obtained. Satisfactory agreement between the calculated and me-asured values shows that the model can reflect the structural characteristics of Fe-Cr-C melts.

关键词： activity, coexistence theory mass action concentration saturated state

Applicability of mass action law to sulphur distribution between slag melts and liquid iron

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Journal of university of science and technology beijing 2002年第2期9卷 90-98页

作者： Jian Zhang Metallurgy School, university of science and technology beijing, beijing 100083, China Metall. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

According to the mass action law and the coexistence theory of slagstructure, the calculating models of mass action concentration for CaO-MgO-FeO-Fe_2._3-SiO_2.CaO-MgO-MnO-FeO-Fe_2._3-P_2._5-SiO_2.and CaO-MgO-MnO-FeO-Fe_2._3-Al_2._3-P_2._5-SiO_2.slag melts areformulated and sulphur distribution between the slag melts and liquid iron is treated. It is foundthat CaO, MnO and FeO promote desulphurization, while MgO is detrimental to desulphurization. Inaddition, the sulphur distribution coefficients between the slag melts and liquid iron andpresented.

关键词： mass action law coexistence theory of slag structure activity massaction concentration

Application of annexation principle to the study of thermodynamic properties of Ag-Bi-In metallic melts

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Journal of university of science and technology beijing 2003年第1期10卷 18-20页

作者： Jian ZhangMetallurgy school, university of science and technology beijing, beijing 100083, China Metallurgy school University of Science and Technology Beijing Beijing 100083 China

Based on the measured activities, the phase diagrams and the annexation principle, the calculating models of mass action concentrations for Ag-Bi and Ag-Bi-In melts have been formulated. The calculated results agree with practice and obey the mass action law, showing that the models formulated can reflect the structural characteristics of both melts. Meanwhile, it confirms that annexation principle is applicable to the Ag-Bi-In metallic melts. The melts involving eulectic which give rise to phase separation, and in which activities exhibit positive deviation from Raoult's law is the basic cause of melts transforming from homogeneous to heterogeneous ones.

关键词： the mass action law annexation principle two phase melts activity, mass action concentration

Application of the annexation principle to the study of thermodynamic properties of ternary metallic melts In-Pb-Ag and In-Bi-Sb

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Rare Metals 2002年第2期21卷 142-151页

作者： ZHANG JianMetallurgical Engineering school.university of science and{2. beijing, beijing 100083, China Metallurgical Engineering School University of Science and Technology Beijing 北京 100083

Based on the phase diagrams, measured activities an the annexationprinciple, the calculating models of mass action concentrations forin-Pb-Ag and In-Bi-Sb ternary metallic melts have been *** results of calculation both agree with practice, and obey the lawof mass action, showing that the models formulated can reflect thestructural reality of the corresponding melts and the annexationprinciple is applicable to the them.

关键词： activity mass action concnetration th annexation principle In-PB-Ag

Laser-field-induced magnon amplification in a magnetic semiconductor quantum well under an external magnetic field

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Journal of university of science and technology beijing 2003年第5期10卷 69-72页

作者： Peng FengPhysics Department, university of science and technology beijing, beijing 100083, China Phys. Dept. Univ. of Sci. and Technol. Beijing Beijing 100083 China

The laser-field induced magnon amplification in a magnetic semiconductorquantum well under an external magnetic field was discussed, it is shown that when the laserfrequency is near to the electron cyclotron frequency, no matter how weaker the laser field is, themagnon amplification always occurs. In case of fixed laser frequency, the optical absorption ofmagnons obeys the definite selection rule to the laser field strength. The rate of change of magnonoccupation is calculated, and the amplification condition is given.

关键词： magnon amplification magnetic semiconductor quantum well laser field