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Global analysis theory of climate system and its applications

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Chinese Science Bulletin 2003年第10期48卷 1034-1039页

作者： LI Jianping1,2.& CHOU Jifan2.3.1. LASG, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 10002., China 2. Department of Atmospheric Sciences, Lanzhou university, Lanzhou 73.000, China 3. Training center for China Meteorological Administration, Beijing 100081, China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Department of Atmospheric Sciences Lanzhou University Lanzhou 730000 China Training center for China Meteorological Administration Beijing 100081 China

The idea and main theoretical results of the global analysis theory of climate system are briefly summarized in this paper. A theorem on the global behavior of climate system is given, i.e. there exists a global attractor in the dynamical equations of climate, any state of climate system will be evolved into the global attractor as time increases, indicating the nonlinear adjustment process of climate system to external forcing. The different effects of external forcing, dissipation and nonlinearity on the long-term behavior of solutions are pointed out, and some main applications of the global analysis theory are also introduced. Especially, three applications, the adjustment and evolution processes of climate, the principle of numerical model design and the optimally numerical integration, are discussed.

关键词：整体分析理论气侯体系应用不定性计算法则气侯科学数字模型

Statistical theory for hydrogen bonding fluid system of A_aD_d type (I): The geometrical phase transition

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Science China Chemistry 2006年第6期49卷 499-506页

作者： WANG Haijun1,2. HONG Xiaozhong3. GU Fang1 & BA Xinwu1 1. College of Chemistry and Environment Science, Hebei university, Baoding 071002. China 2. International center for Materials Physics, Chinese Academy of Sciences, Shenyang 110016, China 3. College of Physics Science and Technology, Hebei university, Baoding 071002. China College of Chemistry and Environment Science Hebei University Baoding China International center for Materials Physics Chinese Academy of Sciences Shenyang China College of Physics Science and Technology Hebei University Baoding China

The influence of hydrogen bonds on the physical and chemical properties of hydrogen bonding fluid system of AaDd type is investigated from two viewpoints by the principle of statistical mechanics. In detail, we proposed two new ways that can be used to obtain the equilibrium size distribution of the hydrogen bonding clusters, and derived the analytical expression of a relationship between the hydrogen bonding free energy and hydrogen bonding degree. For the nonlinear hydrogen bonding systems, it is shown that the sol-gel phase transition can take place under proper conditions, which is further proven to be a kind of geometrical phase transition rather than a thermodynamic one. Moreover, several problems associated with the geometrical phase transition and liquid-solid phase transition in nonlinear hydrogen bonding systems are discussed.

关键词： hydrogen bonding fluid, equilibrium free energy, geometrical phase transition.

Flatness and Profile Integration Control Model for Tandem Cold Mills

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Journal of Iron and Steel Research International 2012年第3期19卷 31-37页

作者： SHAN Xiu-ying1,2.3. LIU Hong-min1,2. JIA Chun-yu1,2. SUN Jian-liang1,2.(1. Engineering Research center of Rolling Equipment and Complete Technology of Ministry of Education, Yanshan university, Qinhuangdao 066004, Hebei, China 2. State Key Laboratory of Metastable Materials Science and Technology, Yanshan university, Qinhuangdao 066004, Hebei, China 3. Hot Tandem Rolling Factory, Jinan Iron and Steel Co Ltd, Jinan 2.0101, Shandong, China) Engineering Research center of Rolling Equipment and Complete Technology of Ministry of Education Yanshan University Qinhuangdao Hebei China State Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao Hebei China Hot Tandem Rolling Factory Jinan Iron and Steel Co Ltd Jinan Shandong China

Using the effective matrix methods of flatness and profile control synthetically, the flatness and profile in- tegration control scheme for tandem cold mills is built in order to increase flatness and profile control precision of tan- dem cold mills. Corresponding control strategies are adopted for various control objectives of different stands and the coordination control strategies of various stands are given, which makes the on-line flatness control cooperate with on-line profile control and implements the parallel control of different stands. According to the measured flatness and profile data of some 1550 mm tandem cold mills, the control scheme is verified and the result indicates that the scheme has high flatness and profile control precision with steady and reliable control process. A new way and method is supplied for researching shade control of tandem cold mills.

关键词： flatness profile shape effective matrix tandem cold mill

Controlled Size and Density Distribution of Nanoparticles by Thermal Ammonia Etching Method

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Journal of Wuhan university of Technology(Materials Science) 2010年第1期25卷 108-111页

作者：李刚 Key Laboratory of Ministry of Education for Conveyance and Equipment East China Jiaotong University center for Photon Fabrication Science and Technology Jiangsu University

Nickel nanometer catalyst thin films were prepared on SiO2.Si substrates using sputtering coater. The effects of ammonia pretreatment on the catalyst films from continuous film to the nanoparticles were investigated. The nanostructures of the Ni thin films as a function of the catalyst film original thickness, the pretreatment time and temperature were discussed. The optimum parameters of etching process were obtained, and the functional mechanism of ammonia was primarily analyzed. Scanning electron microscopy （SEM） and atomic force microscopy （AFM） were used to evaluate the obtained nanoparticles. It is demonstrated that the controlled size and density distribution of the nanoparticles can be achieved by employing ammonia etching method.

关键词： ammonia etching nanoparticle density control thermal expansion

熊果酸的Raman光谱和红外光谱结构特征比较

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光谱学与光谱分析 2002年第6期22卷 970-972页

作者：顾柏平朱亮柯惟忠陈建伟南京中医药大学基础医学院江苏南京210029 南京中医药大学药学院江苏南京210029 南京师范大学分析测试中心江苏南京210024

本文采用HRD2.双光栅单色仪测定了熊果酸的Raman光谱 ,得到熊果酸的特征Raman光谱结构 ,采用Philips 10 0型双光栅单色仪测定了熊果酸的IR光谱 ,得到熊果酸的特征IR光谱结构 ;解析了熊果酸的Raman光谱和IR光谱与其结构特征的关系 ,确... 详细信息

本文采用HRD2.双光栅单色仪测定了熊果酸的Raman光谱 ,得到熊果酸的特征Raman光谱结构 ,采用Philips 10 0型双光栅单色仪测定了熊果酸的IR光谱 ,得到熊果酸的特征IR光谱结构 ;解析了熊果酸的Raman光谱和IR光谱与其结构特征的关系 ,确定了熊果酸的Raman光谱和IR光谱的结构特征和官能团的归属 ,给出了熊果酸的两个基本骨架特征区域 (A区 :13.6 ,13.0 ,13. 3.m- 1 ,B区 :13. 4 ,12.6 9,12.3.cm- 1 ) ;对熊果酸的Raman光谱和IR光谱作了比较研究 ,指出Raman光谱具有比IR光谱更为丰富的结构信息的特征 ,并且 ,IR光谱的主要特征峰在Raman光谱中均有对应的谱峰 ;Raman光谱的谱峰形态清晰可变 ,使熊果酸的主要结构和官能团得到准确的分析和指认 ,与IR光谱一样 ,Raman光谱是天然药物解析的有效手段之一。

关键词：熊果酸激光Raman光谱红外光谱结构解析天然药物

A method of constructing a database-free optimal dynamical system and a global optimal dynamical system

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Science China(Physics,Mechanics & Astronomy) 2008年第7期51卷 905-915页

作者： WU ChuiJie1? & WANG Liang2.1 State Key Laboratory of Structural analysis for Industrial Equipment, Dalian university of Technology, Dalian 11602., China 2.Research {2. for Fluid Dynamics, School of Science, PLA university of Science and Technology, nanjing 2.1101, China State Key Laboratory of Structural analysis for Industrial Equipment Dalian University of Technology Dalian China Research center for Fluid Dynamics School of Science PLA University of Science and Technology Nanjing China

In this paper, to overcome the drawbacks of POT which minimize the reminder, not only the optimal functional with minimal residual is put forward, but also the method of global optimization is used. Under the condition of large reminder, the optimal bases can also be obtained through the method of POTres without the approaching of initial conditions. In addition, compared with local optimization, the advantage of global optimization is remarkable. On the one hand, we can expect that the dynamical system based on the global optimal bases will include more information than the ones based on the local optimal bases, since the global optimal bases are much more precise than the local optimal bases. On the other hand, from the point of view of error, the global optimal bases are independent of the choice of the object functional and the initial bases.

关键词： dynamical system residual global optimization

Seabed Classification Using BP Neural Network Based on GA

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Acta Oceanologica Sinica 2003年第4期22卷 523-531页

作者： Yang Fanlin1, Liu Jingnan2.1. GPS Engineering Research center, Wuhan university, Wuhan 43.079, China. 2. Presidential Secretariat, Wuhan university, Wuhan 43.079, China GPS Engineering Research center Wuhan University Wuhan 430079 China Presidential Secretariat Wuhan University Wuhan 430079 China

Side scan sonar imaging is one of the advanced methods for seabed study. In order to be utilized in other projects, such as ocean engineering, the image needs to be classified according to the distributions of different classes of seabed materials. In this paper, seabed image is classified according to BP neural network, and. Genetic Algorithm is adopted in train network in this paper. The feature vectors are average intensity, six statistics of texture and two dimensions of fractal. It considers not only the spatial correlation between different pixels, but also the terrain coarseness. The texture is denoted by the statistics of the co-occurrence matrix. Double Blanket algorithm is used to calculate dimension. Because a uniform fractal may not be sufficient to describe a seafloor, two dimensions are calculated respectively by the upper blanket and the lower blanket. However, in sonar image, fractal has directivity, i. e. there are different dimensions in different direction. Dimensions are different in acrosstrack and alongtrack, so the average of four directions is used to solve this problem. Finally, the real data verify the algorithm. In this paper, one hidden layer including six nodes is adopted. The BP network is rapidly and accurately convergent through GA. Correct classification rate is 92.5 % in the result.

关键词： BP network co-occurrence matrix fractal classification genetic algorithin

Local and non-local sources of airborne particulate pollution at Beijing——The ratio of Mg/Al as an element tracer for estimating the contributions of mineral aerosols from outside Beijing

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Science China Chemistry 2005年第3期48卷 253-264页

作者： HAN Lihui1, ZHUANG Guoshun1,2.3. SUN Yele1 & WANG Zifa3.1. The center for Atmospheric Environmental Study, Department of Chemistry, Beijing Normal university, Beijing 100875, China 2. center for Atmospheric Chemistry Study, Department of Environmental Science & Engineering, Fudan university, Shanghai 2.043., China 3. LAPC/NZC, Institute of Atmospheric Physics, CAS, Beijing 10002., China The center for Atmospheric Environmental Study Department of Chemistry Beijing Normal University Beijing China center for Atmospheric Chemistry Study Department of Environmental Science & Engineering Fudan University Shanghai China Institute of Atmospheric Physics CAS LAPC/NZC Beijing China

A new element tracer technique has firstly been established to estimate the contri-butions of mineral aerosols from both inside and outside Beijing. The ratio of Mg/Al in aerosol is a feasible element tracer to distinguish between the sources of inside and outside Beijing. Mineral aerosol, inorganic pollution aerosol mainly as sulfate and nitrate, and organic aerosol are the major components of airborne particulates in Beijing, of which mineral aerosol accounted for 3.0}―67% of total suspended particles （TSP）, 10%―70% of fine particles （PM2.5）, and as high as 74% and 90% of TSP and PM2.5, respectively, in dust storm. The sources from outside Beijing contributed 62. （3.%―86%） of the total mineral aerosols in TSP, 69% （52.―90%） in PM10, and 76% （59%―93.） in PM2.5 in spring, and 69% （52.―83.）, 79% （52.―93.）, and 45% （7%―79%） in TSP, PM10, and PM2.5, respectively, in winter, while only2.% in summer and autumn. The sources from outside Beijing contributed as high as 97% during dust storm and were the dominant source of airborne particulates in Beijing. The contributions from outside Bei-jing in spring and winter are higher than those in summer, indicating clearly that it was related to the various meteorological factors.

关键词： mineral aerosol local sources non-local sources dust storm re-suspended dust element tracer technique.

Detection of subcritical crack propagation for concrete dams

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Science China(Technological Sciences) 2009年第12期52卷 3654-3660页

作者： BAO TengFei1 ,2.YU Hong 1,2.1College of Water Conservancy&Hydropower Engineering,Hohai university,{3. 2.0098,China 2.ational Engineering Research {2. of Water Resources Efficient Utilization and Engineering Safety,{3. 2.0098,China College of Water Conservancy & Hydropower Engineering Hohai University Nanjing China National Engineering Research center of Water Resources Efficient Utilization and Engineering Safety Nanjing China

Subcritical propagation of cracks is a warning sign of *** such propagation is detected at an early stage,timely maintenance measures can be taken to prevent the failure of *** detect the subcritical propagation of a crack,the crack needs to be monitored continuously in a long term, which is not realistic under certain ***,cracks in concrete dams can be monitored continuously by dam monitoring to offer possible detection for subcritical *** this paper, with measured crack openings from dam monitoring,a state equation for characterizing crack development is established based on the grey system *** relation between the stability of the equation and the subcritical crack propagation is investigated,then a criterion is proposed for detecting subcritical *** example demonstrates the validity of the criterion and its potential for practical application.

关键词： crack subcritical propagation criterion concrete