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基于交叉梯度交替结构约束的二维地震走时与全通道直流电阻率联合反演

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地球物理学报 2016年第11期59卷 4310-4322页

作者：高级张海江中国科学技术大学地球和空间科学学院地震与地球内部物理实验室合肥230026 安徽万泰地球物理技术有限公司合肥230026

在利用不同的地球物理勘探方法对地下复杂介质成像时,因观测系统的非完备性及数据本身对某些岩石物性的不敏感性,单独成像的结果存在较大的不确定性和不一致性.对于地震体波走时成像与直流电阻率成像,均面临着成像阴影区问题.对于地震... 详细信息

在利用不同的地球物理勘探方法对地下复杂介质成像时,因观测系统的非完备性及数据本身对某些岩石物性的不敏感性,单独成像的结果存在较大的不确定性和不一致性.对于地震体波走时成像与直流电阻率成像,均面临着成像阴影区问题.对于地震走时成像,地震射线对低速区域覆盖较差形成阴影区,造成低速区域分辨率降低.对于电阻率成像,电场线在高阻区域分布较少,造成高阻区域分辨率较低.为了提高地下介质成像的精度,Gallado和Meju(2003)提出了基于交叉梯度结构约束的联合地球物理成像方法.在要求不同的物性模型拟合各自对应的数据同时,模型之间的结构要求一致,即交叉梯度趋于零.为了更有效地实现基于交叉梯度的结构约束,我们提出了一种新的交替结构约束的联合反演流程,即交替反演不同的数据而且在反演一种数据时要求对应的模型与另一个模型结构一致.新的算法能够更容易地把单独的反演系统耦合在一起,而且也更容易建立结构约束和数据拟合之间的平衡.基于新的联合反演流程,我们测试了基于交叉梯度结构约束的二维跨孔地震走时和直流电阻率联合成像.合成数据测试表明,我们提出的交替结构约束流程能够很好地实现基于交叉梯度结构约束的联合成像.与单独成像结果相比,地震走时和全通道电阻率联合成像更可靠地确定了速度和电阻率异常.

关键词：体波走时成像电阻率成像结构相似性交叉梯度联合反演

Synthesis and Lubrication of Phosphorylcholine Derivative

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Journal of Bionic Engineering 2010年第3期7卷 254-258页

作者： Zhenliang Qiao~1. Dangsheng Xiong~1. Lude Lu~2, Pengju jiang~2 1. Department of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 21.094, P.R. China 2. School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 21.094, P. R. China [a] Department of Materials Science Engineering Nanjing University of Science Technology Nanjing 210094 P.R. China [b] School of Chemical Engineering Nanjing University of Science Technology Nanjing 210094 P. R. China

The monomer of phosphorylcholine derivative, O-(5-（2-methacryloxy）-3, 3-dimethyl-3-azapentyl)-O’-（ω-hydroxy-octyl）-phosphatequaternary ammonium salt, was designed and synthesized successfully. It was characterized by the spectra ofHNMR and Mass spectra （ESI+）, and every signal was assigned. Then the lubricating characteristics of the phosphorylcholinederivative were investigated on the tribological setup of ball-oh-flat. The Ultra-High Molecular Weight Polyethylene（UHMWPE） flat was rotated against a stainless steel ball with 6 mm diameter. The load was 2.3 N, which corresponded to amaximal Hertz contact pressure of 29 MPa. Water, phosphorylcholine derivative, and Acrylic Acid （AA） solution were used aslubricants, respectively. Compared with AA, the phosphorylcholine derivative shows significant lubrication. It can be stronglyhydrated under water due to the charged segment in chemical structure. The thick water layers within the chains serves asboundary lubricants, and this is thought to be the molecular origins of lubricating behavior.

关键词： artificial joint articular cartilage molecular lubrication mechanism phosphorylcholine synthesis UHMWPE

Adjoint method for the optimum planning of industrial pollutant sources

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Science China Earth Sciences 2005年第8期48卷 1270-1279页

作者： LIU Feng1.2, HU Fei2 & ZHU jiang2 1. College of Environmental Sciences, Peking University, Beijing 1.0871. China 2. LAPC, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 1.0029, China 1. College of Environmental Sciences Peking University 100871 Beijing China 2. LAPC Institute of Atmospheric Physics Chinese Academy of Sciences 100029 Beijing China

The optimum planning of industrial pollutant sources, which optimizes the economic object without violating environmental constraints, is an important and hard task to be conquered. In this paper, an adjoint method is developed to solve the problem. The penalty function is in-troduced to deal with the environmental inequality constraints, and Lagrange function is con-structed to derive the adjoint equation and the gradient of the object function. In this means, the gradient of the object function can be calculated by solving the adjoint equation, and the infor-mation from the gradient is used to make the object function descend and approach to an optimal solution after some iterations. A two-dimensional, simplified model is used for numerical experi-ments. The theoretical derivations are verified by the results of the experiments. Furthermore, the adjoint method is shown to be of excellent convergence and efficiency, which is adaptive to the fast development of air quality numerical models and super computers.

关键词： optimum planning, industrial pollutant sources, adjoint equation, penalty function, gradient.

Dynamic change of net primary productivity and fractional vegetation cover in the Yellow River Basin using multi-temporal AVHRR NDVI Data

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Journal of Geographical Sciences 2002年第1期12卷 29-34页

作者： SUN Rui1. LIU Chang-ming2, ZHU Qi-jiang1.(1. Department of Geography, Beijing Normal University, Beijing 1.0875, China 2. Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 1.01.1. China) Department of Geography Beijing Normal University 北京 100875 Institute of Geographic Sciences and Natural Resources Research CAS 北京 100101

An exponential relationship between net primary productivity (NPP) and integrated NDVI has been found in this paper. Based on the relationship and using multi-temporal 8 km resolution NOAA AVHRR-NDVI data, the spatial distribution and dynamic change of NPP and fractional vegetation cover in the Yellow River Basin from 1.82 to 1.99 are analyzed. Finally, the effect of rainfall on NDVI is examined. Results show that mean NPP and fractional vegetation cover have an inclining trend for the whole basin, and rainfall in flood season influences vegetation cover most.

关键词： net primary productivity fractional vegetation cover rainfall remote sensing

Analysis and Modeling on the Spatial Structure of Urban Land Use: A Case of Jinan, China

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Chinese Journal of Population,Resources and Environment 2007年第2期5卷 34-40页

作者： Zhao Huixia1. 3, Zhang Zulu2, jiang Luguang 1.1. Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 1.01.1. China 2. College of Population, Resources and Environment, Shandong Normal University, Jinan Shandong 25001., China 3. Graduate School of the Chinese Academy of Sciences, Beijing 1.0039, China Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China College of Population Resources and Environment Shandong Normal University Jinan Shandong 250014 China

Based on the data of urban land use obtained by remote sensing interpretation from aero images in 1.86 and 2004, the spatial structure of Jinan is studied in this paper with the method of Geographic Information System (GIS). According to the proportion of land for residence, industry and commerce, the urban district can be distinguished into three rings. Compared with the traditional theory of the ring structure in Western coun- tries, they have many distinctive characteristics. The main func- tions of the inner ring include residence, business and banking, but the proportion of residential land (more than 50%) is considerably higher than that of the cities in Western countries. The land proportion for residence and industry in the intermediate ring is equal on the whole. The main land of the outside ring is for industrial use. From 1.86 to 2004, great changes have taken place on the land proportion of different types of use. In the inner ring, the land for residential and industrial use has shrunk much while the land for commercial use has increased. In the intermediate ring, the changes of the three types of land use were not very much and the temporal variation was relatively stable. On the contrary, the structure in the outside ring varies acutely. Though most of it is also for industrial use, the proportion of residential land has in- creased much. The three rings can also be divided into several sectors respectively, according to the function of land use clusters. New trends and mechanisms of the changes of land use impacting the urban structure were proposed in the end of the paper.

关键词： urban land use ring structure sector structure Jinan

DSC Analysis of LT-3 Aluminum Alloy Vacuum Brazing

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Journal of Shanghai Jiaotong university(Science) 2005年第2期10卷 182-185,189页

作者：冯涛吴鲁海楼松年李亚江 School of Materials Science and Eng. Shanghai Jiaotong Univ. Shanghai 200030 China School of Materials Science and Eng. Shandong Univ. Ji'nan 250061

LT-3 aluminum alloy is a kind of two-side cladding aluminum special used in vacuum brazing. Differential Scanning Calorimeter （DSC） was used to measure the exothermic and endothermic reaction during the brazing process that the cortex metal and the base metal are melted and re-crystal. The analysis results inidicate that eutectic reaction is the main reaction in the melted cortex metal crystallization process. But the main reaction in the melted base metal crystallization process is the reaction that α-A1.segregated out. According to the experimental details, the critical work of nucleation is 3.82×1.-1.J, the critical radius of nucleation is 8.69×1.-1. m, the volume of critical crystal nucleus is 2.75×1.-27 m3 and the per unit cell in critical crystal nucleus is 43.

关键词： aluminum alloy differential scanning calorimeter(DSC) analysis critical nucleation

Tension and Thickness Control Strategy Analysis of Two Stands Reversible Cold Rolling Mill

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Journal of Iron and Steel Research International 2012年第10期19卷 20-25页

作者： LIU Guang-ming1. DI Hong-shuang2, ZHOU Cun-long1. LI Hong-cui3, LIU jiang3 (1. College of Materials Science and Engineering, Taiyuan University of Science and Technology, Taiyuan 030024, Shanxi, China 2. State Key Laboratory of Rolling and Automation, Northeastern University, Shenyang 1.081., Liaoning, China 3. Cold Rolling Plant, Jinan Iron and Steel Group Co Ltd, Jinan 2501.1. Shandong, China) [a] College of Materials Science and Engineering Taiyuan University of Science and Technology Taiyuan 030024 Shanxi China [b] State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110819 Liaoning China [c] Cold Rolling Plant Jinan Iron and Steel Group Co Ltd Jinan 250101 Shandong China

In order to lucubrate the rolling characteristic of the two stands reversible cold rolling mill and establish the tension and thickness control strategy, the steady-state characteristic simulating program was established using the steady-state continuous rolling theory. The influences of each factor on exit thickness under different tension control methods were analyzed. The results show that, the influence of the entry stand gap on exit thickness is significant and it changes little with different tension control methods. As a result, the entry stand gap can be used as the main control method of exit thickness, whereas rolling speed of any stand and roll gap of the exit stand can be used to adjust the inter-stand tension. The results are beneficial for thickness and tension control of the two stands reversible cold rolling mill.

关键词： two stand reversible cold rolling thickness tension control strategy

Feature extraction and classification of hyperspectral remote sensing image oriented to easy mixed-classified objects

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中国有色金属学会会刊：英文版 2005年第S1期15卷 168-171页

作者： ZHANG Lian-peng~1. LIU Guo-lin~2, jiang Tao~2 (1. Department of Territory Information and Surveying Engineering, Xuzhou Normal University, Xuzhou 221.09, China 2. Shandong University of Science and Technology, Tai’an 271.1.,China) Xuzhou Normal Univ Dept Terr Information & Surveying Engn Xuzhou 221009 Peoples R China Shandong Univ Sci & Technol Tai An 271019 Peoples R China

The classification of hyperspectral remote sensing data is an important problem theoretically and practically. With the increase of spectral bands, the separability of objects on remote sensing image should be improved. But the effects of traditional algorithm on feature extraction such as principal component analysis(PCA) is not so good for hyperspectral image. The key problem is that PCA can only represent the linear structure of data set; while the data clouds of different objects on hyperspectral image usually distribute on a nonlinear manifold. This paper established an algorithm of nonlinear feature extraction named as nonlinear principal poly lines, based on the algorithm, a classifier is constructed and the classification accuracy of hyperspectral image can be improved.

关键词： hyperspectral remote sensing feature extraction classification

五里峡水库初级生产力对水气界面二氧化碳和甲烷排放速率时空变化的影响

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环境科学 2018年第6期39卷 2673-2679页

作者：彭文杰李强宋昂靳振江桂林理工大学环境科学与工程学院桂林541004 中国地质科学院岩溶地质研究所国土资源部/广西岩溶动力学重点实验室桂林541004 联合国教科文组织国际岩溶研究中心桂林541004

近年来水库温室气体备受关注,为揭示水库水气界面CO_2和CH_4在时间和空间上的变化特征,于201.年7~1.月采用静态箱法在五里峡水库对其CO_2和CH_4排放速率进行4次监测,并测试微型光合生物初级生产力等.结果表明,五里峡水库夏季为大气CO_2... 详细信息

近年来水库温室气体备受关注,为揭示水库水气界面CO_2和CH_4在时间和空间上的变化特征,于201.年7~1.月采用静态箱法在五里峡水库对其CO_2和CH_4排放速率进行4次监测,并测试微型光合生物初级生产力等.结果表明,五里峡水库夏季为大气CO_2的汇,变化范围在-30.1.^-3.47 mg·(m^2·h)^(-1.,秋、冬季均为大气CO_2的源,变化范围在1..57~1.5.06 mg·(m^2·h)^(-1..甲烷排放速率在夏季变化幅度明显,变化范围在0.08~1.03 mg·(m^2·h)^(-1.,而在秋、冬季变化稳定,变化范围在-0.07~0.43 mg·(m^2·h)^(-1..受水库周期性蓄水和排水影响,CO_2和CH_4排放速率在空间上表现为水库消落带和坝尾较低而库区较高的分布格局.此外,CO_2和CH_4排放速率时空变化与微型光合生物初级生产力分别呈显著负相关和正相关(r为-0.477和0.771..这是因为产甲烷菌能够将夏季微型光合生物固定的有机碳转化成CH_4释放到大气中,从而使微型光合生物对水圈CO_2和CH_4循环产生负反馈效应和正反馈效应.因此,本研究结果为进一步评估微型生物对岩溶水体碳循环的贡献提供了理论依据.

关键词：五里峡水库温室气体排放速率时空变化初级生产力