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Strong earthquake activity all over the world and strong-moderate earthquake activity within and near China (December, 2000 ~ January, 2001)

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Acta Seismologica Sinica(English Edition) 2001年第2期14卷 356-357页

作者： CHEN pei-shan 1. Institute of Geophysics China Seismological Bureau 100081 Beijing China

IllustrationAll the data in this catalog are chosen from the 2Preliminary Seismological Report of Chine-se Seismic Stations2 (Its abbreviation is 2Monthly Report2). The catalog includes the events of M34.7 in and near China and M36 all over the world. The 2Monthly Report2 is monthly compiled by the Ninth Section of Institute of Geophysics, CSB.The origin times of earthquakes in the catalog adopt coordinated universal time (UTC) in accordance with international convention. The location of every epicenter is expressed by its latitude and longitude, at the same time by the corresponding geographical region proposed by Flinn and Engdahl. The regional names are only for references and do not imply any political significance. The number of stations used and standard deviation are also given in order to illus-trate the precision of location.The surface wave magnitude MS is measured from the records of intermediate period broad band SK seismographs and adopting the surface wave magnitude formula of Beijing Station of 1965: MS= lg(AH/T)+1.66lgD +3.5 (1°pei in 1967. MS7=lg(AV/T)+1.66lgD +3.3 (20°

关键词： CLC number P315.5

Two 3-D multi-cascade co-design inverse methods based on streamline curvature approach and Clebsch formulation for single-stage centrifugal compressors

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航空动力学报 2013年第7期28卷 1526-1538页

作者： TIAN Xiao-pei shan Peng School of Energy and Power Engineering Beijing University of Aeronautics and Astronautics

Two strategies extended the single-cascade methods from a compressible three-dimensional inverse method for radial and mixed flow turbomachines to two three-dimensional multi-cascade co-design methods for single-stage centrifugal *** two three-dimensional methods and a typical quasi-threedimensional streamline curvature through-flow inverse method were employed to design the same subsonic high-speed single-stage centrifugal *** compressor performances were simulated by a commercial Reynolds averaged Navier-Stokes(RANS) equations *** studies show that two three-dimensional codesign methods are reasonable and *** was found that : firstly the blade camber angle designed by the three-dimensional methods was larger than that designed by the quasi-three-dimensional method;and secondly with regard to two three-dimensional methods with different boundary conditions,the co-design result differences between the diffusers were small,but those between the deswirlers were relatively large.

关键词： centrifugal compressor through-flow inverse method three-dimensional inverse problem streamline curvature approach Clebsch formulation multi-cascade co-design

Numerical Simulation of Microstructure Evolution for SA508-3 Steel during Inhomogeneous Hot Deformation Process

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Journal of Iron and Steel Research International 2014年第11期21卷 1022-1029页

作者： Da-shan SUI Fei CHEN pei-pei ZHANG Zhen-shan CUI National Die & Mold CAD Engineering Research Center Shanghai Jiao Tong University

Based on hot compression tests by a Gleeble-1500D thermo-mechanical simulator, the flow stress model and microstructure evolution model for SA508-3 steel were established through the classical theories on work hardening and softening. The developed models were integrated into 3D thermal-mechanical coupled rigid plastic finite element software DEFORM3D. The inhomogeneous hot deformation （IHD） experiments of SA508 3 steel were designed and carried out. Meanwhile, numerical simulation was implemented to investigate the effect of temperature, strain and strain rate on microstructure during IHD process through measuring grain sizes at given positions. The simulated grain sizes were basically in agreement with the experimental ones. The results of experiment and simulation demonstrated that temperature is the main factor for the initiation of dynamic recrystallization （DRX）, and higher temperature means lower critical strain so that DRX can be facilitated to obtain uniform fine microstructure.

关键词： SA508-3 steel inhomogeneous hot deformation microstructure evolution grain size numerical simulation

Game Theory and the Evolution of Cooperation

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Journal of the Operations Research Society of China 2022年第2期10卷 379-399页

作者： Bo-Yu Zhang shan pei Laboratory of Mathematics and Complex Systems Ministry of EducationSchool of Mathematical SciencesBeijing Normal UniversityBeijing 100875China

Evolution is based on the competition between individuals and therefore rewards only selfish *** cooperation or altruism behavior could prevail in social dilemma then becomes a problematic *** theory offers a powerful mathematical approach for studying social *** has been widely used to explain the evolution of *** this paper,we first introduce related static and dynamic game *** we review two types of mechanisms that can promote cooperation in groups of genetically unrelated individuals,(i)direct reciprocity in repeated games,and(ii)incentive mechanisms such as reward and punishment.

关键词： Cooperation Game theory Direct reciprocity Reward Punishment

Strong　earthquake　activity　all　over　the　world　and　strong-moderate　earthquake　activity　within　and　nea

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Acta Seismologica Sinica(English Edition) 1998年第4期11卷 515-516页

作者： pei-shan Chen Institute of Geophysics China Seismological Bureau Beijing China

Ｓｔｒｏｎｇｅａｒｔｈｑｕａｋｅａｃｔｉｖｉｔｙａｌｌｏｖｅｒｔｈｅｗｏｒｌｄａｎｄｓｔｒｏｎｇ－ｍｏｄｅｒａｔｅｅａｒｔｈｑｕａｋｅａｃｔｉｖｉｔｙｗｉｔｈｉｎａｎｄｎｅａｒＣｈｉｎａ（Ｆｅｂｒｕａｒｙ，１９９８－... 详细信息

Ｓｔｒｏｎｇｅａｒｔｈｑｕａｋｅａｃｔｉｖｉｔｙａｌｌｏｖｅｒｔｈｅｗｏｒｌｄａｎｄｓｔｒｏｎｇ－ｍｏｄｅｒａｔｅｅａｒｔｈｑｕａｋｅａｃｔｉｖｉｔｙｗｉｔｈｉｎａｎｄｎｅａｒＣｈｉｎａ（Ｆｅｂｒｕａｒｙ，１９９８－Ｍａｒｃｈ，１９９８）ＰＥＩ－ＳＨ...

关键词： over all the world activity Strong

Machining Error Control by Integrating Multivariate Statistical Process Control and Stream of Variations Methodology

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Chinese Journal of Aeronautics 2012年第6期25卷 937-947页

作者： WANG pei ZHANG Dinghua LI shan CHEN Bing Key Laboratory of Contemporary Design and Integrated Manufacturing Technology Ministry of Education Northwestern Polyteehnical University Xi'an 710072 China

For aircraft manufacturing industries, the analyses and prediction of part machining error during machining process are very important to control and improve part machining quality. In order to effectively control machining error, the method of integrating multivariate statistical process control （MSPC） and stream of variations （SoV） is proposed. Firstly, machining error is modeled by multi-operation approaches for part machining process. SoV is adopted to establish the mathematic model of the relationship between the error of upstream operations and the error of downstream operations. Here error sources not only include the influence of upstream operations but also include many of other error sources. The standard model and the predicted model about SoV are built respectively by whether the operation is done or not to satisfy different requests during part machining process. Secondly, the method of one-step ahead forecast error （OSFE） is used to eliminate autocorrelativity of the sample data from the SoV model, and the T2 control chart in MSPC is built to realize machining error detection according to the data characteristics of the above error model, which can judge whether the operation is out of control or not. If it is, then feedback is sent to the operations. The error model is modified by adjusting the operation out of control, and continually it is used to monitor operations. Finally, a machining instance containing two operations demonstrates the effectiveness of the machining error control method presented in this paper.

关键词： machining error multivariate statistical process control stream of variations error modeling one-step ahead forecast error error detection

Deciphering the leakage conduction mechanism of BiFeO_(3)–BaTiO_(3)lead-free piezoelectric ceramics

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Journal of Advanced Ceramics 2023年第10期12卷 1844-1856页

作者： Mengping Xue Yucheng Tang Zhihang shan Yijin Hao Xiaoxiao zhou Xiaoqi Gao Hezhang Li Jun pei Boping Zhang The Beijing Municipal Key Laboratory of New Energy Materials and Technologies School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China Department of Precision Instrument Tsinghua UniversityBeijing 100084China

BiFeO_(3)–BaTiO_(3)(BF–BT)based piezoelectric ceramics are a kind of high-temperature lead-free piezoelectric ceramics with great development prospects due to their high Curie temperature(TC)and excellent electrical ***,large leakage current limits their performance improvement and practical *** this work,direct current(DC)test,alternating current(AC)impedance,and Hall tests were used to investigate conduction mechanisms of 0.75BiFeO_(3)–0.25BaTiO_(3)ceramics over a wide temperature *** the range of room temperature(RT)−150℃,ohmic conduction plays a predominant effect,and the main carriers are p-type holes with the activation energy(Ea)of 0.51 *** T>200℃,the Ea value calculated from the AC impedance and Hall data is 1.03 eV with oxygen vacancies as a cause of high *** diffusion behavior of thermally activated oxygen vacancies is affected by crystal symmetry,oxygen vacancy concentration,and distribution,dominating internal conduction *** the conduction mechanisms over the three temperature ranges would pave the way for further improving the insulation and electrical properties of BiFeO_(3)–BaTiO_(3)ceramics.

关键词： BiFeO_(3)-BaTiO_(3)(BF-BT) leakage behavior conduction mechanism oxygen vacancies Hall test

A sensitive detection of high Rydberg atom with large dipole moment

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Chinese Physics B 2018年第7期27卷 345-350页

作者： shan-shan Zhang Hong Cheng pei-pei Xin Han-Mu Wang Zi-shan Xu Hong-Ping Liu State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 China University of Chinese Academy of Sciences Beijing 100049 China

We report a sensitive detection of high Rydberg atom with large dipole moment utilizing its deflection near a pair of parallel cylindrical copper rods which are oppositely charged. When the low-field seeking state Rydberg atoms fly across the gradient electric field formed by the pair of rods, they will be pushed away from the rods while the high-field seeking state ones will be attracted towards the rods. These atoms will form different patterns on an ion imaging system placed downwards at the end of the rods. The spatial distribution of the deflected atoms on the imaging system is also simulated, in good agreement with the experimental results, from which we can deduce the quantum state information of the excited atoms. This state resolvable Rydberg atom detection can be used for the dynamics research of the dipole-dipole interaction between atoms with large dipole moments.

关键词： Rydberg Stark state sodium atom deflection dipole moment

SYNTHESIS OF A POTENTIAL ANTIFEEDANT SESOUITERPENE INTERMEDIATE FROM A NEW TERPENOID A, B-RING SYNTHON BY TANDEM NICHAEL REACTION

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Chinese Chemical Letters 1992年第10期3卷 767-770页

作者： pei Qiang HUANG Wei shan zhou shanghai Institute of Organic Chemistry Academia Sinica345 Lingling LuShanghai 200032 Department of Chemistry Xiamen UniversityXiamen 361005

An efficient synthesis of functionalized 6-decalone 16, starting from a dienolate anion 3a via a tandem Michael reaction, is described. 16 could be used as a potential intermediate for synthesis of drimane related ses... 详细信息

关键词： Vita SYNTHESIS OF A POTENTIAL ANTIFEEDANT SESOUITERPENE INTERMEDIATE FROM A NEW TERPENOID A B-RING SYNTHON BY TANDEM NICHAEL REACTION