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Mid-Holocene climate change in North china, and the effect on cultural development

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Chinese Science Bulletin 2002年第5期47卷 408-413页

作者： JIN Guiyun & LIU Dongsheng (LIU Tungsheng)institute of Cultural Relics and Archaeology of shandong Province, jinan 250012, china institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, china institute of Cultural Relics and Archaeology of shandong Province Jinan China institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

In this study, to reconstruct the paleoclimatic history, pollen and oxygen isotope were analyzed on the 160 samples of a 2.7 m peat core from Taishizhuang, Huailai County, Hebei Province. Combining our data with other information of climate history and archaeology from this area, we found that there is a close linkage between cultural development and the mid-Holocene (6000-3000 cal. aBP) environment changes. The main results and conclusions are presented as the following: The climate during 5678-5400 cal. aBP was unstable and in general colder and drier than today. From 5400 to 4800 cal. aBP the climate was much warmer and wetter than before. The climate during 4800-4300 cal. aBP was persistently cold, with an exceptional cold event occurring at 4600-4300 cal. aBP. This cold event was recorded at several other localities in Northern china even the Northern Hemisphere and played an important role in the cultural development. After the cold event, there was a return to warmer conditions between 4200 and

关键词： North china peat mid-Holocene cold event cultural development.

Biogas charging and dissipating process and its accumulation in the Sebei gasfield,Qaidam Basin,china

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Science china Earth Sciences 2008年第S1期51卷 36-44页

作者： JIN Qiang 1,CHENG FuQi 1,2 ,SU AiGuo 3 ,ZHU GuangYou 3 ,WANG Li 1 &CAO Qian 1 1 china University of Petroleum,Dongying,shandong 257061,china 2 Geological institute of Shengli Oilfield,SINOPEC,Dongying,shandong 257015,china 3 Petroleum Exploration and Development institute,Petrochina,Beijing 100083,china china University of Petroleum Dongying China Geological institute of Shengli Oilfield SINOPEC Dongying China Petroleum Exploration and Development institute PetroChina Beijing China

The Sebei gasfield is the largest biogas accumulation found in china and many reservoirs and seal rocks superposed on a syndepositional anticline in *** biogas charging and dissipating process and its distribution have been a research focus for many *** authors suggest a diffusing and accumulating model for the biogas,as they find that the shallower the gas producer,the more methane in the biogas,and the lighter stable carbon isotope composition of *** on the diffusing model,diffused biogas is quantitatively estimated for each potential sandy reservoir in the gasfield,and the gas charging quantity for the sandy reservoir is also calculated by the diffused gas quantity plus gas reserve in-place.A ratio of diffusing quantity to charging quantity is postulated to describe biogas accumulating state in a sandy reservoir,if the ratio is less than 0.6,the reservoir forms a good gas-pool and high-production layer in the gasfield,which often occurs in the reservoirs deeper than 900 m;if the ratio is greater than 0.6,a few gas accumulated in the reservoir,which frequently exists in the reservoirs shallower than 900 ***,a biogas accumulation model is built up as lateral direct charging from gas source for the sands deeper than 900 m and indirect charging from lower gas-bearing sands by diffusion at depth shallower than 900 *** this charging and diffusion quantitative model,the authors conducted re-evaluation on each wildcat in the central area of the Qaidam Basin,and found many commercial biogas layers.

关键词： biogas charging and diffusing model relative dissipated quantity Qaidam Basin

ESTIMATION OF LOCAL HYSTERETIC PROPERTIES FOR SHAPE MEMORY ALLOYS

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Chinese Journal of Mechanical Engineering 2002年第1期15卷 27-30页

作者： Dong Yuping institute of Mechanical Engineering，shandong University，jinan 250061，china Wang Zhonghua Southeast University Song Chengli Cardiff School of Engineering institute of Mechanical Engineering Shandong University Jianan 250061 Southeast University Cardiff School of Engineering

The applicability of shape memory alloys (SMAs) in structural dynamics,particularly as hysteretic damping elements, is limited by the difficulties in modelling theirdeformation characteristics. At typical engineering design levels of loading SMAs exhibitpseudo-elastic properties. A combined experimental and simulation approach suitable for thecharacterisation of novel smart devices based on the pseudo-elastic effect is described.

关键词： Shape memory alloys Hysteretic properties Pseudo-elastic properties

Intermediate processes and critical phenomena: Theory, method and progress of fractional operators and their applications to modern mechanics

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Science china(Physics,Mechanics & Astronomy) 2006年第3期49卷 257-272页

作者： XU Mingyu1 & TAN Wenchang2 1. institute of Applied Mathematics, School of Math & System Science, shandong University, jinan 250100, china 2. State Key Laboratory of Turbulence and Complex Systems & Department of Mechanics and Engineering Science, Peking University, Beijing 100871, china institute of Applied Mathematics School of Math & System Science Shandong University Jinan China State Key Laboratory of Turbulence and Complex Systems & Department of Mechanics and Engineering Science Peking University Beijing China

From point of view of physics, especially of mechanics, we briefly introduce fractional operators (with emphasis on fractional calculus and fractional differential equa- tions) used for describing intermediate processes and critical phenomena in physics and mechanics, their progress in theory and methods and their applications to modern me- chanics. Some authors’ researches in this area in recent years are included. Finally, prospects and evaluation for this subject are made.

关键词： fractional operators,intermediate processes,critical phenomena,modern mechanics

A VARIATION OF GOLDFARB'S METHOD FOR LINEARLY CONSTRAINED OPTIMIZATIONPROBLEMS AND ITS SUPERLINEAR CONVERGENCE RATE

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Systems Science and Mathematical Sciences 1998年第4期11卷 351-358页

作者： SHI Zhenjun ZHANG Yuzhong(institute Of Operations research, Qufu Normal University, Qse 273165, china)LI Qun(shandong Financial College, jinan 25000, china)

This paper presents a variant algorithm of Goldfarb’s method for linearlyconstrained optimization problems. In the variant algorithm, we introduce a concept calledconjugate projection, which differs from orthogonal p... 详细信息

关键词： Conjugate projection superlinear convergence rate global convergence

THE ROTATION NUMBER AND DIRECTION OF A CONTINUOUS FLOW ON THE TORUS

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Chinese Annals of Mathematics,Series B 1988年第2期9卷 207-215页

作者：韩茂安 shandong Mining institute Taian shandong china.

In this paper the rotation direction r_f and rotation number p_f for any continuous flowon the torus are defined by applying Weil's theorem proved by *** followingresults are obtained:（i）r_f=0 iff all orbits of f are proper and each limit set of f is homotopic to zeo onT2;（ii）if r_f≠0,then p_f is irrational iff f has at least one non-trivial P stable orbit,p_f isrational iff f has at least one non-zero-homotopic closed or singular closed *** a method of computing the rotation number of certain flows is given.

关键词： Th THE ROTATION NUMBER AND DIRECTION OF A CONTINUOUS FLOW ON THE TORUS

Zonal propagation of kinetic energy and convection in the South china Sea and Indian monsoon regions in boreal summer

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Science china Earth Sciences 2004年第12期47卷 1076-1084页

作者： CHEN Longxun 1 ,GAO Hui 2 ,HE Jinhai 2 ,TAO Shiyan 3 & JIN Zuhui 3 1.Chinese Academy of Meteorological Sciences,Beijing 100081,china 2.Nanjing institute of meteorology,Nanjing 210044,china 3.institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,china Chinese Academy of Meteorological Sciences Beijing China Nanjing institute of meteorology Nanjing China Chinese Academy of Sciences Institute of Atmospheric Physics Beijing China

Zonal propagation of kinetic energy (KE) and convection in the South china Sea (SCS) and Indian summer monsoon areas are examined in present study. Results suggest that the SCS and Indian summer monsoon prevailed regions (5 —15°N) are dominated by the southwesterly wind, however, the disturbances of KE at 850 hPa and convection are observed mainly coming from the western Pacific Ocean (140—150°E), after passing through the SCS, and westward propagated into the Bay of Bengal (90—100°E). In the Indian summer monsoon domain, where the disturbances of KE are found mainly coming from the Arabian Sea (AS) and eastward propagated into the Bay of Bengal. Therefore, the SCS and the Indian summer mon- soon are quite different in zonal propagation of KE and convection. The SCS summer monsoon is mainly affected by the KE and convection coming from the tropical western Pacific. The Indian summer monsoon, however, can be partly influenced by the AS and the SCS summer monsoon. The analysis also suggests that the interaction region between the SCS and the Indian summer monsoon is around 90—95°E, rather than 105°E as proposed by earlier studies.

关键词： zonal propagation of KE and convection, East Asian monsoon, Indian monsoon.

Micromechanical analysis of interaction energy for SMA reinforced composite

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Science china(Technological Sciences) 2009年第3期52卷 610-616页

作者： ZHU YuPing1,2, DUI GuanSuo1 & DUO Liu3 1 institute of Mechanics, Beijing Jiaotong University, Beijing 100044, china 2 Department of Engineering Mechanics, Jiangsu University, Zhenjiang 212013, china 3 State Key Lab of Crystal Materials, shandong University, jinan 250100, china institute of Mechanics Beijing Jiaotong University Beijing China Department of Engineering Mechanics Jiangsu University Jiangsu China State Key Lab of Crystal Materials Shandong University Jinan China

The energy of the interaction between the matrix and the inclusions in shape memory alloy (SMA) re- inforced composite is one of the most important and complicated parts in thermodynamic constitutive theory. In this paper, the interaction energy is derived based on the classical theory of micromechanics and the thermodynamic theory. The SMA composite is treated as three phases, namely the austenitic phase, the martensite phase and the matrix phase. The interaction among the three phases is analyzed in a way close to the fact. The present expression is used to calculate the interaction energy of a typical SMA composite with attentions paid to understand of the effects of the matrix material, the fiber ge- ometry, and the fiber/matrix volume ratio. It is shown that the method developed in this paper is credible compared with the references. Some useful conclusions are obtained.

关键词： shape memory alloy interaction energy SMA composite micromechanics thermodynamics

Numerical simulation of topography effects on the “00.7” severe rainfall in Beijing

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Progress in Natural Science:Materials International 2005年第9期15卷 818-826页

作者： ZHANG Chaolin1**, JI Chongping1, KUO Yinghwa2, FAN Shuiyong1, XUAN Chunyi3 and CHEN Min1(1. institute of Urban meteorology, china Meteorological Administration, Beijing 100089, china 2. Mesoscale and Microscale meteorology Division, National Center for Atmospheric research, Boulder, CO 80307-3000, USA 3. Beijing Meteorological Bureau, Beijing 100089, china) institute of Urban meteorology China Meteorological Administration Beijing 100089 China Mesoscale and Microscale meteorology Division National Center for Atmospheric Research Boulder CO 80307-3000 United States Beijing Meteorological Bureau Beijing 100089 China

In an effort to study the severe rainfall event of 4—5th July 2000 in Beijing (with 24h accumulated precipitation of 240 mm), we perform numerical simulations to investigate this event using the MM5v3.6 model. The model is initialized with the MM5/WRF 3DVAR analysis, which incorporates the ground-based GPS precipitable water vapor, automatic and conventional meteorological observations in its assimilation step. For 24 h accumulated precipitation forecast, the threat scores are 0.72, 0.76, 0.67 and 0.63, for thresholds of 1, 5, 10, and 20 mm, respectively. Holding other factors unchanged, sensitivity experiments were conducted with different topographic resolutions of 110, 50 and 3.7 km to investigate the topographic effects on precipitation over the Beijing area. In these sensitivity experiments, we attempt to preserve the realistic orographic distribution in the model topography under the condition of keeping the dynamic-thermodynamic consistency of the initial model atmosphere to the extent possible. Results indicate that the unique topographic distribution and variations in the Beijing area play an important role in determining the location, distribution and intensity of heavy precipitation.

关键词： topography heavy rainfall 3DVAR ground-based GPS numerical simulation.