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Measurement of Double Differential Cross Section for ^(93)Nb(n,xp) Reaction at E_n=14.6 MeV

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chinese journal of nuclear physics 1994年第2期16卷 120-126页

作者： Ye Bangjiao Fan Yangmei Wang Zhongmin Han Rongdian(Department of Modern Physics,University of science and Technology of china,Hefei 230026)Xiao Zhenxi(Institute of Management,University of science and Technology of china,beijing 100080) 中国科学技术大学近代物理系安徽合肥 230026 中国科学技术大学近代物理系安徽合肥中国科学技术大学管理学院北京 100080

-The energy spectrum and angular distributions of protons from 93Nb（n,xp）reactions are measured by means of the USTC（University of science and Technologyof china）multitelescope *** total proton production cross sections are in fairagreement with the results of other *** energy spectrum is well explained by thesum of the spectra calculated on the basis of the preequilibrium and the H-F *** from the previous measurement at the high energy end of the angle-inte-grated proton spectrum are *** angular distributions which show a stronglyenergy-dependent forward-backward asymmetry are in fair agreement with thephenomenological model of Kalbach-Mann.

关键词： Double differential cross section Neutron induced reaction Preequilibrium

Detecting Lags in Nonlinear Models Using General Mutual Information

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Journal of Mathematical Research and Exposition 2010年第1期30卷 87-98页

作者： Wei GAO1,2, Zheng TIAN1,3 1. Department of Applied Mathematics, Northwest Polytechnical University, Shaanxi 710072, P. R. china 2. school of Statistics, Xi’an University of Finance & Economics, Shaanxi 710061, P. R. china 3. National Key Laboratory of Pattern Recognition, Institute of Automation, chinese academy of sciences, beijing 100080, P. R. china Department of Applied Mathematics Northwest Polytechnical University Shaanxi P.R.China 710072

The general mutual information （GMI） and general conditional mutual information （GCMI） are considered to measure lag dependences in nonlinear time series. Both of the measures have the property of invariance with transform. The statistics based on GMI and GCMI are estimated using the correlation integral. Under the hypothesis of independent series, the estimators have Gaussian asymptotic distributions. Simulations applied to generated nonlinear series demonstrate that the methods appear to find frequently the correct lags.

关键词： general mutual information general conditional mutual information nonlinear time series lag dependence.

COMPUTER SIMULATION OF EFFECT OF ORIENTATION DIFFERENCE ON MECHANICAL PROPERTIES OF BICRYSTALLINE SPECIMENS

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Acta Metallurgica Sinica(English Letters) 1991年第1期4卷 13-16页

作者： WEI Chao QIAN Rengen LIN Shi XIAO Jimei University of science and Technology beijing,beijing,china Dept.of Mathematics and Mechanics,University of science and Technology beijing,Bijing 100083,china

Based on the experimental results of the work-hardening processes of single crystals,the ac- commodation processes of polycrvstal deformation and the assumption of idealized polycrystal,the stress-strain relation of elasto-plastic deformation crystal was *** effect of orientation difference on the mechanical properties of the bicrvstalline specimens of aluminum was simulated by means of the finite element method(FEM)of elasto-plastic *** results are in good agreement with the experimental results made by Clark and Chalmers in 1954.

关键词： bicrystal orientation difference grain boundary computer simulation finite element method

PREDICTION AND CONTROL OF BOTH WRINKLE AND FRACTURE LIMITS ON CYLINDRICAL CUP MULTI DEEP DRAWING

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chinese Journal of Mechanical Engineering 1999年第4期12卷 288-296页

作者： Lei Junxiang Yantai UniversityKang Yonglin University of science and Technology beijing 烟台大学机械工程系山东烟台 264005 北京科技大学压力加工系北京

Based on the superfluous triangle material wrinkle model,the no wrinkle limit criterion of cylindrical cup multi deep drawing is calculated as the prediction and control of the wrinkle *** to fracture model,the no fracture limit criterion of cylindrical cup multi deep drawing is calculated as the prediction and control of the fracture *** the no wrinkle limit criterion with the no fracture limit criterion,the no wrinkle and no fracture limit criterion and diagram on cylindrecal cup multi deep drawing are given as the prediction and control of both wrinkle and fracture *** accordance with this can determine the limit deep drawing coefficient and minimum deep drawing coefficient,and can choose the deep drawing coefficient of multi deep drawing,blank holder force and deformation force by optimization choice *** calculation and test data are highly consistent,and suitable for no flange multi deep drawing,flange multi deep drawing and rigid punch expanding

关键词： Cylindrical cup Multi deep drawing Wrinkle limit Fracture limit control Optimization choice method

Learning interactions among multi-channel sequences with dynamical influence models

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science china(Information sciences) 2010年第7期53卷 1336-1344页

作者： ZHANG WeiDong, CHEN Feng & XU WenLi Department of Automation, National Laboratory for Information science and Technology, Tsinghua University, beijing 100084, china 1. Department of Automation National Laboratory for Information Science and Technology Tsinghua University Beijing 100084 China

Many real applications involve simultaneous recording and analysis of multi-channel information sources. Learning and modeling the interactions among channels is the kernel step to analyze and recognize system characteristics. This paper presents a model that learns the dynamical influence among multi-channel sequences. The model, dynamical influence model, permits functional roles of individual channels to change and models the changing influence strength between channels. By querying the values of influence factors, we can recognize the functional role of each channel qualitatively and learn about to what extent the chains influence each other quantitatively at any time. The experimental results on synthetic data and application of multi-person interaction recognition show that our model is reliable and effective.

关键词： multi-channel processing dynamical interaction influence model activity recognition

A　Diference　Scheme　with　Anti－difusion　Terms　to　Improve　the　Computation　of　Contact　Discontinuities　and　the　Study　of　Weak　Discontinuities　in　Compresible　Flow

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Communications in Nonlinear science and Numerical Simulation 1996年第4期1卷 42-51页

作者： Chunguang XU (College of Mathematical science ,Peking University, beijing 100871) College of Mathematical science Peking University beijing 100871 USA

Ａｂｓｔｒａｃｔ：ＴｈｅｉｎｖｅｓｔｉｇａｔｉｏｎｏｆＭａｃｈｒｅｆｌｅｃｔｉｏｎｆｏｒｍｅｄａｆｔｅｒｔｈｅｉｍｐｉｎｇｅｍｅｎｔｏｆａｗｅａｋｐｌａｎｅｓｈｏｃｋｗａｖｅｏｎａｗｅｄｇｅ，ｗｉｔｈｓｈｏｃｋＭａｃ... 详细信息

Ａｂｓｔｒａｃｔ：ＴｈｅｉｎｖｅｓｔｉｇａｔｉｏｎｏｆＭａｃｈｒｅｆｌｅｃｔｉｏｎｆｏｒｍｅｄａｆｔｅｒｔｈｅｉｍｐｉｎｇｅｍｅｎｔｏｆａｗｅａｋｐｌａｎｅｓｈｏｃｋｗａｖｅｏｎａｗｅｄｇｅ，ｗｉｔｈｓｈｏｃｋＭａｃｈｎｕｍｂｅｒＭｓｎｅａｒ１，ｉｓｓｔｉｌａｎｏｐｅｎｐｒｏｂｌｅｍ［１２］．Ｉｔ＇ｓｄｉｆｉｃｕｌｔｆｏｒｓｈｏｃｋｔｕｂｅｅｘｐｅｒｉｍｅｎｔｓｗｉｔｈｉｎｔｅｒｆｅｒｏｍｅｔｅｒｔｏｄｅｔｅｃｔｃｏｎｔａｃｔｄｉｓｃｏｎ－ｔｉｎｕｉｔｉｅｓ，ｉｆｉｔｉｓｔｏｏｗｅａｋ；ａｌｓｏｄｉｆｉｃｕｌｔｔｏｃａｔｃｈｗｉｔｈｄｕｅａｃｃｕｒａｃｙｔｈｅｔｒａｎｓｉｔｉｏｎｃｏｎｄｉｔｉｏｎｂｅｔｗｅｅｎＭａｃｈｒｅｆｌｅｃｔｉｏｎａｎｄｒｅｇｕｌａｒｒｅｆｌｅｃｔｉｏｎ．Ｔｈｅｉｎｔｅｒｅｓｔｔｏｔｈｉｓｐｈｅｎｏｍｅｎｏｎｉｓｃｏｎｔｉｎ－ｕｉｎｇ，ｅｓｐｅｃｉａｌｙｆｏｒｗｅａｋｓｈｏｃｋｓ，ｂｅｃａｕｓｅｔｈｅｒｅｗａｓｓｙｓｔｅｍａｔｉｃｄｉｓｃｒｅｐａｎｃｙｂｅｔｗｅｅｎｓｉｍ－ｐｌｉｆｉｅｄｔｈｒｅｅｓｈｏｃｋｔｈｅｏｒｙｏｆｖｏｎＮｅｕｍａｎｎ［８］ａｎｄｓｈｏｃｋｔｕｂｅｒｅｓｕｌｔ

关键词： weak reflection Mach reflection anti-diffusion

Epigenetic reprogramming in mammalian nuclear transfer

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chinese science Bulletin 2004年第8期49卷 766-771页

作者： LI Shijie1,2, DU Weihua1 & LI Ning1 1. State Key Laboratory for Agrobiotechnology, china Agricultural University, beijing 100094, china 2. Department of Biochemistry and Molecular Biology, College of Life science, Hebei Agriculture University, Baoding 071001, china Correspondence should be addressed to Li Ning (e-mail: ninglbau@ ***) State Key Laboratory for Agrobiotechnology China Agricultural University Beijing 100094 China Department of Biochemistry and Molecular Biology College of Life Science Hebei Agriculture University Baoding 071001 China

Somatic cloning has been succeeded in some species, but the cloning efficiency is very low, which limits the application of the technique in many areas of research and biotechnology. The cloning of mammals by somatic cell nuclear transfer (NT) requires epigenetic reprogramming of the differentiated state of donor cell to a totipotent, embry-onic ground state. Accumulating evidence indicates that in-complete or inappropriate epigenetic reprogramming of do-nor nuclei is likely to be the primary cause of failures in nu-clear transfer. This review summarizes the roles of various epigenetic mechanisms, including DNA methylation, histone acetylation, imprinting, X-chromosome inactivation, te-lomere maintenance and expressions of development-related genes on somatic nuclear transfer.

关键词：哺乳动物细胞核液迁移后成程序改编 DNA甲基化作用组蛋白乙酰化作用 X-染色体活化端粒印痕基因表达克隆

Mapping the MLT tides from meteor radar observations of a meridional chain

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Mapping the MLT tides from meteor radar observations of a me...

A new Planetary Boundary Layer model and its application to heavy rain modeling

中国地球物理学会第二十七届年会

作者： You Yu~(1,2) Weixing Wan~(1*) Baiqi Ning~1 Libo Liu~1 Zhengui Wang~(1,2) 1.beijing National Observatory of Space Environment,Institute of Geology and Geophysics, chinese academy of sciences,beijing,10029 2.Graduate University of chinese academy of sciences,beijing 100049, china

＜正＞Mesosphere and low thermosphere（MLT）,as an important coupling region in upper atmosphere,plays important roles in the dynamical processes as well as the transportation of energy and *** decades, to understand this complicated dynamical region,extensive wind observations have been conducted from the ground-based and space-based *** of observations have revealed a wealth of information on atmospheric tides,but they suffer from lack of global structure and local time coverage *** article proposes a technique to map the tidal winds in mesosphere and lower thermosphere（MLT） region from the observation of the meteor radar chain located along the 120°E meridional circle in china[*** et al,2004]. The observed zonal and meridional winds were first decomposed into mean,diurnal,semidiurnal and terdiurnal tidal components in the altitude range 82～94 km for stations at different latitudes（from 18.3°N to 40.3°N） in the

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science Bulletin 2005年第16期 86-96页

作者： SUN Jian, ZHOU Xiuji & ZHAO Ping chinese academy of Meteorological sciences, beijing 100081, china

A new Planetary Boundary Layer (PBL) model (namely MY-4 in this paper) was developed with reference to Mellor-Yamada’s Level 4 turbulent closure concept. Having been coupled with a meso-scale model MM5, MY-4 was util-ized to simulate a heavy-rain process, which took place over South china during June 8-9, 1998. Its model outputs indi-cated that the rainfall process was well captured in terms of its intensity and geographical distribution. More importantly, in comparison with MM5’s original boundary layer models, MY-4 made the following improvements: (1) MY-4 not only simulated the major weather systems like low vortexes and low-level jets more accurately, thus improving the general weather pattern of the rainfall process, but it was also capa-ble of restraining the occurrence of false rainfall centers with maximum precipitation amounts exceeding 160 mm. (2) Having been compared with the wind profile observed at Hong Kong, it revealed that MY-4 could reproduce the wind speed fluctuations in a short time scale reasonably well, which was not yet achieved in the original PBL models in MM5. Furthermore, a more detailed comparative study was made on the results simulated by MY-4 and a PBL model (which is based on Mellor-Yamada’s Level 2.5 concept) re-spectively. It showed that the contributions of turbulences generated by the two categories of PBL models to the wind fields at a lower atmosphere were increasingly different even in the first 1-2 hours of integrations. As the analysis dem-onstrated, under the nonlinear interactions within the meso-scale MM5 model, it was the turbulences in the boundary layer that had the most important impacts on the final model outputs and MY-4 seemed to better reflect this turbulent process, hence leading to the aforementioned im-provements.

关键词： MY-4 PBL model comparative study heavy rain tur-bulent closure.