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An agent-based incentive mechanism for P2P systems

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The Journal of China Universities of Posts and Telecommunications 2006年第4期13卷 81-85页

作者： ZHANG jian-feng WANG Ru-chuan College of Computer Nanjing University of Posts and Telecommunications Nanjing 210003 China State Key Laboratory for Novel Software Technology Nanjing Universtiy Nanjing 210093 China

With the increasing systems, the problems of fair uses of peer-to-peer （P2P） information and resources sharing become serious. P2P systems are self-organizing, distributed systems with no centralized authority, such as Free-riding and Tragedy of Commons. Because of the voluntary participation and lack of motivation, the information and resources available in P2P networks are extremely variable and unpredictable. This article studied the problems existing in P2P networks and propose a different method to stimulate the peers in P2P networks to share information and resources, using agents so as to improve the performance of P2P networks And through simulation experiments and analyzing the results, it can be concluded that this mechanism can effectively solve the problems of fair sharing in P2P systems.

关键词： P2E fair sharing motivate agent

Theoretical Study on GSH Activation Mechanism of a New Type of Glutathione Transferase Gtt2

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Chemical Research in Chinese Universities 2012年第3期28卷 500-502页

作者： LI Xue WU Yun-jian LI Zhuo CHU Wen-ting ZHANG Hong-xing zheng Qing-chuan State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical ChemistryJilin UniversityChangehun 130021P.R.China

Glutathione transferases（GSTs） play an important role in the detoxification of xenobiotic/endobiotic toxic compounds. The α-, π-, and/l-classes of cytosolic GSTs have been studied extensively, while Gtt2 from Saccharo- myces cerevisiae, a novel atypical GST, is still poorly understood. In the present study, we investigated the gluta- thione（GSH） activation mechanism of Gtt2 using the density functional theory（DFT） with the hybrid functional B3LYP. The computational results show that a water molecule could assist a proton transfer between the GSH thiol and the N atom of His133. The energy barrier of proton transfer is 46.0 kJ/mol. The GSH activation mechanism and the characteristics of active site are different from those of classic cytosolic GSTs.

关键词： Quantum chemistry Enzyme catalysis Reaction mechanism Glutathione transferase Glutathione(GSH)activation

Wave mode computing method using the step-split Padé parabolic equation

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Chinese Physics B 2022年第9期31卷 354-361页

作者： chuan-Xiu Xu Guang-Ying zheng Hangzhou Applied Acoustics Research Institute Hangzhou 310023China Science and Technology on Sonar Laboratory Hangzhou 310023China

Models based on a parabolic equation(PE)can accurately predict sound propagation problems in range-dependent ocean ***,this method has developed rapidly in recent *** with normal mode theory,PE focuses on numerical calculation,which is difficult to use in the mode domain analysis of sound propagation,such as the calculation of mode phase velocity and group *** broaden the capability of PE models in analyzing the underwater sound field,a wave mode calculation method based on PE is proposed in this ***-split Pade PE recursive matrix equations are combined to obtain a propagation ***,the eigenvalue decomposition technique is applied to the matrix to extract sound mode eigenvalues and *** experiments on some typical waveguides are performed to test the accuracy and flexibility of the new *** on different orders of Padéapproximant demonstrate angle limitations in PE and the missing root problem is also discussed to prove the advantage of the new *** PE mode method can be expanded in the future to solve smooth wave modes in ocean waveguides,including fluctuating boundaries and sound speed profiles.

关键词： parabolic equation propagation matrix eigenvalue decomposition

An analytical solution to estimate the settlement of tailings or backfill slurry by considering the sedimentation and consolidation

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International Journal of Mining Science and Technology 2021年第3期31卷 463-471页

作者： Jiahao Qin jian zheng Li Li Research Institute of Mining and Environment(RIME UQAT-Polytechnique) Department of CivilGeological and Mining EngineeringMontréalQuébec H3C 3A7Canada

A common and important task in mining industry is to estimate the settlement or final volume of the tailings or backfill associated with sedimentation and self-weight consolidation. Up to now however, most existing analytical solutions were developed by only considering the settlement induced by consolidation. In this paper, the process of shrinkage tests has been compared with those of sedimentation and consolidation. It was shown that the pore water and particles movement in the sedimentation are very similar to that in the normal shrinkage. The void ratio at the end of sedimentation is thus for the first time considered to be equal to the void ratio at desaturation onset of shrinkage tests. An analytical solution was then proposed to estimate the settlement of tailings or backfill by considering the sedimentation and consolidation. To validate the proposed analytical solution, tailing deposition tests were conducted in two molds to simulate the tailings impoundment and underground mine stope. The required parameters were obtained through shrinkage and consolidation tests. Good agreements were obtained between the measured settlements and those calculated by the proposed solution. The proposed solution can thus be considered as validated and used to evaluate the settlement of tailings or backfill slurry.

关键词： Shrinkage Sedimentation Consolidation Settlement Tailings Backfill

A Bifurcated Vascular Channel Construction Method based on Diploic Vein Characteristics

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Journal of Bionic Engineering 2019年第5期16卷 814-827页

作者： jian Qi Jia Li Shuxian zheng Tianjin Key Laboratory of Equipment Design and Manufacturing Technology School of Mechanical EngineeringTianjin UniversityTianjin 300354China School ofMechanical Engineering Tianjin University of Technology and EducationTianjin 300222China

In skull bone tissue engineering,cells do not easily survive and proliferate in the scaffold because of the lack of nutrient transport *** address these problems,a vascular design and fabrication method based on human skull diploic vein characteristics was *** skull sample was scanned by micro-CT,and the 3D model was constructed by *** analyzing the characteristics of the diploic vein,the vascular centerline model,path model,taper model and bifurcation model were *** vascular network examples were constructed by iteration of the bifurcation *** mold method of constructing vascular scaffolds embedded within the bionic channels was *** scaffold material is PDMS,and the surface was coated with *** Human Umbilical Vein Endothelial Cells(HUVECs)were planted into the lumen of the channels for 7 days in vitro and found to be able to *** cells cultured for three days were fluorescently stained,and it was found that the cells were well attached to the surfaces of the *** vascular design and fabrication process can lay a foundation for vascularization in bone tissue engineering.

关键词： diploic vein vascular channels bifurcation model vascular mold vascular scaffold fabrication bionic

Wind induced deformation and vibration of a Platanus acerifolia leaf

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Acta Mechanica Sinica 2012年第3期28卷 583-594页

作者： chuan-Ping Shao Ye-Jun Chen jian-Zhong Lin China Jiliang University 310018 HangzhouChina

Deformation and vibration of twig-connected sin- gle leaf in wind is investigated experimentally. Results show that the Reynolds number based on wind speed and length of leaf blade is a key parameter to the aerodynamic prob- lem. In case the front surface facing the wind and with an in- crease of Reynolds number, the leaf experiences static defor- mation, large amplitude and low frequency sway, reconfigu- ration to delta wing shape, flapping of tips, high frequency vibration of whole leaf blade, recovery of delta wing shape, and twig-leaf coupling vibration. Abrupt changes from one state to another occur at critical Reynolds numbers. In case the back surface facing the wind, the large amplitude and low frequency sway does not occur, the recovered delta wing shape is replaced by a conic shape, and the critical Reynolds numbers of vibrations are higher than the ones correspond- ing to the case with the front surface facing the wind. A pair of ram-horn vortex is observed behind the delta wing shaped leaf. A single vortex is found downstream of the conic shaped leaf. A lift is induced by the vortex, and this lift helps leaf to adjust position and posture, stabilize blade distortion and reduce drag and vibration.

关键词： Tree leaf. Wind. Deformation Vibration

Reply to Comment by Steinberger on 'Will Earth's next supercontinent assemble through the closure of the Pacific Ocean?'

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National Science Review 2022年第12期9卷 71-72页

作者： chuan Huang zheng-Xiang Li Nan Zhang Earth Dynamics Research Group The Institute for Geoscience Research (TIGeR) School of Earth and Planetary Sciences Curtin University Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking University

Geo dynamic modeling of the super continent cycle crosses the fields of geology,geophysics and computational *** thus welcome the comment by *** from the numerical geodynamics point of view,which gives us the opportunity to clarify some of the concepts,explain further our model approach and necessary simplifications,and point out major ambiguities that require further work.

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Magnetization Reversal of Single-Molecular Magnets by a Spin-Polarized Current

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Chinese Physics Letters 2020年第8期37卷 108-113页

作者： Chao Yang zheng-chuan Wang Gang Su School of Physical Sciences University of Chinese Academy of SciencesBeijng 100049China Kavli Institute for Theoretical Physics CAS Center for Excellence in Topological Quantum ComputationUniversity of Chinese Academy of SciencesBeijing 100190China

We study the magnetization reversal of single-molecular magnets by a spin-polarized current in the framework of the spinor Boltzmann *** of the spin–orbit coupling,the spin-polarized current will impose a non-zero spin transfer torque on the single-molecular magnets,which will induce the magnetization switching of the *** the s–d exchange interaction between the conducting electrons and single-molecular magnets,we can investigate the magnetization dynamics of single-molecular *** demonstrate the dynamics of the magnetization based on the spin diffusion equation and the Heisenberg-like *** results show that when the current is large enough,the magnetization of the single-molecular magnets can be *** also calculate the critical current density required for the magnetization reversal under different anisotropy and external magnetic fields,which is helpful for the corresponding experimental design.

关键词： magnetization magnets reversed

Underlying mechanism of ASIC1a involved in acidosis-induced cytotoxicity in rat C6 glioma cells

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Acta Pharmacologica Sinica 2007年第11期28卷 1731-1736页

作者： Xie-chuan WENG,jian-quan zheng~2,Jin LI,Wen-bin XIAOBeijing Institute of Pharmacology and Toxicology,Beijing 100850,China Beijing Institute of Pharmacology and Toxicology Beijing China

Aim:To investigate the underlying mechanism of acid-sensing ion channel (ASIC)la involved in the acidosis-induced cytotoxicity of rat C6 glioma ***:The stable ASIC 1 a-silenced C6 cells built with the RNA interference technologywere confirmed by RT-PCR and Western blot *** calcium([Ca2+]i) in both the wild-type rat C6 glioma cells and the ASIC 1a-silenced C6 cellswere analyzed before and after acid application/exposure with the calcium ***:The rapid extracellular pH drop induced the increase of[Ca2+]iin the wild-type C6 cells,but not in the ASIC1a-silenced C6 *** prolonged acid exposure,[Ca2+]iwas lower in the ASIC 1 a-silenced C6 cellsthan that in the control ***:The resultant toxicity of [Ca2+]imightcontribute to the acidosis-induced cytotoxicity.

关键词： acid-sensing ion channel calcium calcium imaging Fluo-3