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中国科学院地质与地球物理研究所2014年度（第14届）学术年会

作者： ting ma Zhongjie Zhang State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences University of Chinese Academy of Sciences

Irregular surfaces cause a number of problems for seismic processing and interpretation. The problems lie in the proper treatment of topography in the first-arrival travel-time calculation and ray-path tracing, both of which are subject to preconditions in ray-based seismogram synthesis, seismic tomography, and seismic migration calculations. Two treatment schemes for irregular surfaces have been used previously:(1) model expansion with the irregular surface treated as an inner discontinuity, and(2) flattening of the irregular surface using a transformation between curvilinear and Cartesian coordinates, while maintaining it as a free surface. In the first approach,first-arrival travel times can be calculated using an eikonal equation solver, and rays are traced backward from the receiver to the source along the direction of the gradient of the travel-time field. In the second scheme, a topography-dependent eikonal equation is used to calculate irregular-surface first-arrival travel times. We present a ray-path tracing scheme for irregular surfaces, which applies a travel-time field calculated using a topography-dependent eikonal equation. The scheme is realized using travel-time gradients in curvilinear coordinates. The validity of the scheme for tracing ray paths in the presence of irregular topography is illustrated by five models containing differing degrees of topographical complexity. Comparison of ray paths and first-arrival travel times between the two irregular-surface treatment schemes suggests the topography-flattened scheme avoids the difficulties of both discretizing the irregular surface and the velocity selection of the infill medium in the model expansion scheme. For the treatment of the inner discontinuity by model expansion, there is a possibility that ray paths will be traced outside the real physical model. Using the topography-dependent eikonal equation solver with our ray-path tracing scheme should provide an efficient means of dealing with irre

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A model expansion criterion for treating surface topography in ray path calculations using the eikonal equation

A model expansion criterion for treating surface topography ...

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中国科学院地质与地球物理研究所2014年度（第14届）学术年会

作者： ting ma Zhongjie Zhang State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences University of Chinese Academy of Sciences

Irregular surface topography has revolutionized how seismic traveltime is calculated and the data are processed. There are two main schemes for dealing with an irregular surface in the seismic first-arrival traveltime calculation:(1) expanding the model and(2) flattening the surface irregularities. In the first scheme, a notional infill medium is added above the surface to expand the physical space into a regular space, as required by the eikonal equation ***, we evaluate the chosen propagation velocity in the infill medium through ray path tracking with the eikonal equation-solved traveltime field, and observe that the ray paths will be physically unrealistic for some values of this propagation velocity. The choice of a suitable propagation velocity in the infill medium is crucial for seismic processing of irregular topography. Our model expansion criterion for dealing with surface topography in the calculation of traveltime and ray paths using the eikonal equation highlights the importance of both the propagation velocity of the infill physical medium and the topography gradient.

关键词： model fill scheme irregular surface eikonal equation solver ray path

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纳米纤维素:多层次跨尺度无机功能体系的构筑平台

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高分子学报 2020年第8期51卷 833-863页

作者：马小婷徐雁吉林大学无机合成与制备化学国家重点实验室长春130012

现代工业的迅猛发展在为生活带来诸多便利的同时也危及人类赖以生存的生态环境.利用可再生资源,效仿生物材料的构筑特征及构效关系,建立可持续构筑途径,实现功能定向构筑已成为材料研究的重要推手及重大挑战.纳米纤维素来源于自然存储... 详细信息

现代工业的迅猛发展在为生活带来诸多便利的同时也危及人类赖以生存的生态环境.利用可再生资源,效仿生物材料的构筑特征及构效关系,建立可持续构筑途径,实现功能定向构筑已成为材料研究的重要推手及重大挑战.纳米纤维素来源于自然存储量最丰富的纤维素,是纤维素分子的自组装体,以手性、化学可修饰性、机械增强以及自组装等特性引起科学界的极大关注.结合纳米纤维素的本征矿化能力、基于化学组装与化学合成协同作用的辅助矿化以及基于生物合成协同矿化等途径,建立跨尺度多级结构的构建方法,开发高效纳米纤维素基无机功能材料研究具有重要的科学和社会意义.本综述针对纳米纤维素的矿化能力,围绕矿化驱动力、矿化选择性、异质矿化、跨尺度结构化、功能集成、功能定向构筑等重要科学问题,选择代表性纤维素基无机材料进行分析归纳,为推进多层次跨尺度纳米纤维素基无机功能体系的精准构筑提供科学依据.

关键词：纳米纤维素组装合成多层次跨尺度定向构筑

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Changes in the Geographical Distributions of Global Human Settlements

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Journal of Resources and Ecology 2021年第6期12卷 829-839页

作者： YE Hongtao ma ting State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

In recent decades,the continuous growth in the population has significantly changed the area of human settlements across the *** change of human settlements has brought great challenges to human development,environmental change,resource allocation,and disaster prediction and *** the current paper,we integrate data products provided by the European Commission,Joint Research Centre with multi-source remote sensing data to analyze the changing trends of global human settlements under varying geographical distributions from 1990 to *** results demonstrate that on the global scale,human settlements are generally distributed in Europe,East Asia,Southeast Asia,South Asia,the eastern United States,the Gulf Coast and the coast of Oceania,with most of them distributed in urban agglomerations and coastal *** human settlements have continued to grow over the past 25 years,mainly in East Asia,Western Europe and the United *** area of human settlements in eastern Europe has been slightly *** distribution of human settlements is affected by climate,water and terrain *** were more likely to have settled in temperate regions with wetter climates,and most of the human settlements are located within 500 km of the coastline and 30 km of land-based water *** results can provide insights into further investigations of the spatio-temporal dynamics of human settlements and its connections to ecological and environmental issues in a changing world.

关键词： human settlements protected area temporal and spatial variation GHSL

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Big geodata mining:Objective,connotations and research issues

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Journal of Geographical Sciences 2020年第2期30卷 251-266页

作者： PEI Tao SONG Ci GUO Sihui SHU Hua LIU Yaxi DU Yunyan ma ting ZHOU Chenghu State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

The objective,connotations and research issues of big geodata mining were discussed to address its significance to geographical research in this *** geodata may be categorized into two domains:big earth observation data and big human behavior data.A description of big geodata includes,in addition to the“5Vs”(volume,velocity,value,variety and veracity),a further five features,that is,granularity,scope,density,skewness and *** on this approach,the essence of mining big geodata includes four ***,flow space,where flow replaces points in traditional space,will become the new presentation form for big human behavior ***,the objectives for mining big geodata are the spatial patterns and the spatial ***,the spatiotemporal distributions of big geodata can be viewed as overlays of multiple geographic patterns and the characteristics of the data,namely heterogeneity and homogeneity,may change with ***,data mining can be seen as a tool for discovery of geographic patterns and the patterns revealed may be attributed to human-land *** big geodata mining methods may be categorized into two types in view of the mining objective,i.e.,classification mining and relationship *** research will be faced by a number of issues,including the aggregation and connection of big geodata,the effective evaluation of the mining results and the challenge for mining to reveal“non-trivial”knowledge.

关键词： big earth observation data big human behavior data geographical spatiotemporal pattern spatiotemporal heterogeneity knowledge discovery

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Acute Miliary Tuberculosis and Pelvic Tuberculosis after In vitro Fertilization

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Reproductive and Developmental Medicine 2020年第2期4卷 123-127页

作者： Li-Juan Fan ting-ting ma ShanLiu Yun Qi Assisted Reproduction Center of Northwest Women’s and Children’s Hospital Xi’an 710000China Department of Gynecology and Pediatric Tuberculosis Xi’an Chest HospitalXi’an 710100China

Nearly one-fourth of the world’s population is infected with Mycobacterium tuberculosis(MTB).Female genital tuberculosis(TB)is a common cause of infertility in both developing and undeveloped ***,assisted reproduction treatments and pregnancy potentially increase the risk of TB infection and *** this study,we present the case of a 28-year-old infertile female without a history of TB who developed an acute miliary TB and pelvic TB after in vitro fertilization-embryo transfer(IVF-ET).Elevated serum estrogen levels during controlled ovarian hyperstimulation and T-lymphocyte function inhibition during pregnancy are the risk factors for MTB infection and *** her 7 th week of gestation,the patient developed fever and spontaneously *** chest computed tomography images revealed classical miliary *** curettage tissue and vaginal secretion samples as well as Gene X-pert MTB/rifampicin(RIF)and TB-RNA test results were positive for *** examination of the uterine curettage tissue confirmed the diagnosis of endometrial *** with isoniazid,RIF,pyrazinamide,amikacin,and levofloxacin was selected based on the patient’s diagnosis,complications,and test ***,the patient is undergoing anti-TB treatment,and her condition is *** is important to rule out the presence of TB in infertile patients before performing IVF-ET to avoid TB dissemination during pregnancy.

关键词： Acute Miliary Tuberculosis In vitro Fertilization Pelvic Tuberculosis Pregnancy

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浅谈计算机网络安全

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人民长江 2000年第1期31卷 55-56页

作者：马婷婷长江水利委员会保密办湖北武汉430010

利用广泛开放的网络环境进行全球通信已成为时代发展的趋势,但围绕计算机的窃密与反窃密、破坏与反破坏的斗争日益激烈。对于计算机的内部网,影响计算机网络安全的主要因素有网络系统自身的漏洞,计算机病毒感染与黑客攻击以及网络安全... 详细信息

利用广泛开放的网络环境进行全球通信已成为时代发展的趋势,但围绕计算机的窃密与反窃密、破坏与反破坏的斗争日益激烈。对于计算机的内部网,影响计算机网络安全的主要因素有网络系统自身的漏洞,计算机病毒感染与黑客攻击以及网络安全管理等。针对这些问题。

关键词：计算机网络网络安全网络管理

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Research progress on fluorescence analysis of antitumor Chinese medicine components

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Tumor Microenvironment Research 2020年第1期2卷 23-28页

作者： Xiao-ting ma Jing-Na Zhou Hebei University Baoding 071000China

This paper classifies the anti-tumor traditional Chinese medicine's fluorescence analysis and finds that its research content mainly includes two aspects:the application of fluorescence analysis in the determination of the effective component content of anti-tumor traditional Chinese medicine;the study of the combined use of fluorescence imaging technology and the *** to literature analysis,it is found that although the research on the fluorescence analysis of anti-tumor Chinese medicine components is in a good state of development,it still needs to explore further in the identification of unknown components and deeper research on known ***,it can provide a certain basis for clinical guidance of tumor patients.

关键词： Anti-tumor Chinese medicine composition Fluorescence analysis method Content determination Fluorescence imaging

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Cellular and Molecular Basis of Leptin Resistance in Obese Patients

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Food Therapy and Health Care 2020年第3期2卷 122-128页

作者： Xiao-ting ma Shao-qin Ge Hebei University Baoding 071002China

Obesity is a major risk factor for diabetes,cardiovascular disease,and certain *** arises from a chronic positive energy *** is usually due to unrestricted access to food in the context of genetic and epigenetic *** an increasingly sedentary *** the past few decades,our understanding of the fluid and nervous systems that mediate energy balance control has greatly ***,our ability to formulate effective strategies to slow the current obesity epidemic has been hampered,mainly because we have limited knowledge of the resistance mechanisms of metabolic hormones such as *** to leptin is a sign of obesity,leptin is a key hormone for neuroendocrine control of energy *** the past few years,we have made tremendous progress in our in-depth research on the cellular pathways that disrupt the action of *** this review,we discuss the molecular mechanisms of leptin resistance and how to use them as targets for obesity drug therapy.

关键词： Obesity Leptin Leptin resistance Cellular basis Molecular basis

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Leptin and maintaining Weight Gain

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Food Therapy and Health Care 2020年第3期2卷 99-108页

作者： Xiao-ting ma Shao-qin Ge Hebei University Baoding 071002China

In today's society,obesity is the single most important risk factor for early disability and death,and the incidence of obesity is still at an alarming *** central nervous system regulates energy intake and consumption in response to changes in the body's energy storage,thereby maintaining the body's continued obesity;fat cell-derived hormone leptin and its receptor(LEPR)are the key regulators of these *** in the case of insulin resistance,various mechanisms have been proposed(including feedback inhibition,inflammation,glial hyperplasia,and endoplasmic reticulum stress)to interfere with the action of leptin,hindering the system that controls the body's energy balance to promote or maintain obesity,although these are not ***,in ordinary obese patients,the LEPR signal may be increased(rather than impaired),indicating that any obesity-related defects in leptin action must be caused by lesions other than the original LEPR signal.

关键词： Obesity Leptin maintaining body weight Energy balance

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