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《吉林大学学报(地球科学版)》2015,(Z1)
<正>数学建模是运用数学的语言和方法,通过抽象、简化建立能近似刻画并解决实际问题的一种强有力的数学手段。地学领域的大量问题也可以通过数学建模的方法来解决。例如在成矿预测时,可以对已知的地质信息进行综合分析,通过数学建模方法来推测未知的信息,从而在勘探时更有针对性,提高采矿效率。本文将以四川盆地地下深层卤水某储卤构造为例,在已知矿井中常见阴阳离子含量的情况下,通过多元线性回归模型来推测各井中的钾离子含量,在此基础上利用克里格插值法预测该储卤构造的钾元素空间分 相似文献
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结构方程模型是一种建立、估计和检验因果关系的方法。它可以替代多重回归、路径分析、因子分析、协方差分析等方法,清晰分析单项指标对总体的作用和单项指标间的相互关系,是一种主要应用于验证性模型分析的多元统计建模技术。由于能够通过可观测变量来度量潜变量得分以及分析不同子模型下潜变量之间的协同效应等优点,结构方程模型被广泛应用在心理学、行为学、市场学等领域的数据建模分析研究中,提供了从提出概念—设计模型—获取数据—验证模型的成熟应用路径。地学数据的建模技术一直是地学研究的热点之一,其目的是在海量、多元、高维、多时态的地学数据中,提取出有价值的模型结构以及潜变量,研究不同地学变量以及潜变量之间的交互关系,从而支撑环境治理、灾害防治、资源勘察、生态评价等相关应用和研究。随着地学数据规模变化和建模工具的不断发展,地学数据建模的样本逐渐从抽样建模变为全样本建模,建模方式从有地学模型指导下的建模变为无约束/弱约束建模,建模依据从基于变量因果关系建模变为基于变量相关性的建模,模型复杂度从单模型/单过程建模变为多模型/多过程的综合建模。结构方程模型作为一种综合的建模方法,其可以同时包含因子分析、潜变量估计、路径分析等多种多元分析技术,这种多层次、多分支的建模方法融合了知识驱动建模和数据驱动建模的特点。结构方程模型在地学数据建模中主要面临以下三个方面的挑战,一是从主要面向验证性建模分析的方式向探索性建模分析的方式转变;二是从有完整地学模型约束的建模型方式向弱模型/无模型约束的地学数据建模方式转变;三是从无空间属性的统计变量建模向空间统计变量建模的转变。这对模型本身和数据建模的方法都提出了新的要求。针对以上三个问题,文章在回顾结构方程模型的概念和发展历程的基础上,介绍了三个结构方程模型在地学数据建模中的应用案例,一是利用湖泊沉积物地球化学数据在弱约束条件下提取地球化学金矿内生控矿因子的建模案例;二是利用结构方程模型的综合参数优化方法,通过计算后验概率与观察后验概率的匹配约束来弱化、校正证据权模型中证据独立性问题在计算金矿找矿后验概率中的影响;三是利用结构方程模型来研究墨西哥马格达莱纳流域森林保护策略,通过对不同区域的森林区块进行编号,将空间分布数据转变为传统的无空间属性的统计变量,并分析了不同环境策略对森林保护的影响。 相似文献
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基于CAS理论的系统仿真是近年来国内外研究的热点领域之一,在计算机上建立模型进行仿真模拟是研究复杂系统的一个基本方法。Repast仿真平台是目前比较流行的一种建模平台,通过介绍Repast建模的背景,分析该平台的框架结构、特点及运行机制等内容,该平台移植性和可扩展性强,方便应用基于Agent建模仿真方法对复杂适应系统及复杂性的研究及探索,同时也为复杂适应系统的研究提供新的思路。通过介绍国内地理学者对Repast仿真平台的应用,对Repast仿真平台在地理学中的应用前景进行讨论。 相似文献
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三维地质建模是地质数据可视化和空间分析的关键技术之一。针对传统建模方法建模速度慢、建模效率和精度较低的问题,提出了一种直接基于钻孔的点→线→面→体快速递进三维地质建模方法。该方法先对钻孔地层信息进行人机交互对比构成地质剖面,再按钻孔实际坐标在三维空间中还原地质剖面的实际位置,接着通过对剖面间的地层连线进行Kriging插值,形成一系列地层面模型,然后以此为基础构建三维地质框架模型,最后利用BSP矢量剪切技术来裁剪模型边界,形成研究区三维地质模型。该方法在福州市上街镇三维城市地质模型构建的实际应用中得到了验证。实践结果表明,该方法不仅可以实现三维地质模型的快速构建,还可以显著提高三维地质模型的精度。 相似文献
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主要通过对骆驼墩遗址地层样品的粒度和重砂矿物的鉴定、样品中锆石形态的对比研究,铷锶值的测定与分析,了解该区域全新世以来的沉积环境及其气候变化,探索气候变化与人类文明和文化发展的关系。对骆驼墩遗址文化层下的自然淤积层的粒度分析和锆石形态研究发现该区域在人类出现之前可能经历过浅水泻湖环境; 结合重矿物及铷锶研究发现,该区域在全新世早期降水量较大,气候较为湿热,之后气候逐渐变得温暖湿润,为人类文明的出现和文化的发展提供了一个优越的气候条件; 通过对地层中文化层样品的重矿物鉴定及百分含量分析、ZTR稳定系数及Rb/Sr分析发现,全新世的气候是不断变化的。尤其在马家浜文化时期、良渚文化时期和广富林文化时期气候经历过温湿与干凉的交替变化过程。同时良渚文化时期的中晚期稳定系数出现了该地层的最高值,说明当时气候较为湿热,降水量偏多,这与良渚文化的消失与洪水有关的结论相一致。 相似文献
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支持多源异构数据的三维地质建模方法一直是三维地质建模研究的重点和难点之一。本文以北京市通州城市副中心工程地质勘察为例,设计了一种多源数据三维地质模型自动建模方法。该方法首先在数据预处理阶段,利用剖面、地震剖面解译及等值面(线)等数据生成虚拟钻孔,从而将异构的多源数据统一转换成同构的虚拟钻孔数据,然后利用钻孔和虚拟钻孔实现三维地质结构的自动化建模;根据已构建的三维地质结构创建属性模型结构约束,采用六面体网格或四面体的单元结构构建属性模型网格;属性模型网格中的每个属性块通过三维空间插值方法进行属性赋值,然后将属性变化映射为颜色变化,建立了相应的三维地质属性模型,实现了多源数据三维地质结构模型约束的属性建模。该方法已经应用在工程地质勘察和城市地下空间开发等领域,通过使用多源异构的建模数据,使构建的三维地质模型更加完善,有助于三维地质模型的推广和应用。 相似文献
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杨赤中推估法是一种对空间域复合变量通过连续的几何滤波过程来建立核函数的最小二乘推估法,建模过程简便且能基于少量已知数据点取得好的建模效果。针对地质勘查中离散、稀疏而不规则分布的地质特征点数据难以构建地质体三维模型的难点问题,提出了一种基于杨赤中推估法的三维地质空间插值与模型建立的自动化方法。该方法首先以地质特征点数据库为基础,选用负幂指数函数模型建立适合三维地质空间插值的杨赤中推估法估值数学模型;在此基础上,构建一套基于杨赤中推估法的三维地质空间插值计算和地质体隐式建模的自动化实现流程与程序;最后以实例矿化插值数据为基础,采用基于移动立方体算法的三维隐式建模方法,快速构建实例矿体三维模型。与人工交互圈定地质体边界和进行矿体推断的三维地质显式建模相比,这种方法能快速直观地分析地质特征并处理样品分析数据,方法可行且高效。 相似文献
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三维矿床地质模型的不确定性对矿山生产决策有着重要影响,正确地对矿床地质模型进行不确定性分析可以对其本身和在其基础上所做的决策作出科学评价。矿床地质模型的不确定性主要来自于建模数据和插值方法的不确定性。通过对建模数据的产生、处理过程的分析,利用处理不确定性问题的理论和方法建立建模数据的不确定性模型。通过对建模方法产生的理论误差和实测误差进行量化,实现对建模方法不确定性的定量描述。将建模数据的不确定性和建模方法的不确定性进行叠置分析,建立矿床模型的不确定性模型。以内蒙古自治区某煤矿的地质资料为例,通过不确定性分析,建立了该矿的不确定性三维矿床地质模型。 相似文献
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随着煤层气勘探的不断深入,对煤层含气量预测精度提出了更高的要求。基于煤层含气量测井响应特征,分析测井参数与含气量的相关性,提出MIV（Mean Impact Value）技术与LSSVM（Least Squares Support Vector Machine）结合的测井参数优选策略,优选最优测井参数作为网络建模的输入自变量组合,通过粒子群算法优化LSSVM网络核心参数,最后构建一套适用于煤层含气量预测的MIV-PSO-LSSVM模型。在此基础上,分别对比分析LSSVM、PSO-LSSVM、MIV-LSSVM和MIV-PSO-LSSVM模型对煤层含气量的预测性能,并与传统多元回归方法进行了对比,利用拟合优度和均方根误差对此5类模型进行评价。结果表明:PSO优化下的LSSVM模型预测精度得到有效提升,结合MIV方法优选测井参数可大幅度改善神经网络建模性能,MIV-PSO-LSSVM模型可实现煤层含气量高精度预测,为煤层气勘探及其储层评价提供新的技术支撑,且本研究的建模策略及思想可广泛应用于其他机器学习建模研究领域。 相似文献
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An overview of climate change vulnerability: a bibliometric analysis based on Web of Science database 总被引：4，自引：1，他引：3
Based on worldwide scholars’ 3,004 papers published in 658 academic journals in the Web of Science database on the topic of climate change vulnerability from 1991 to 2012, this paper quantitatively analyzes the global scientific performance and hot research areas in this field by adopting bibliometric method. The results show that (1) the vulnerability researches on climate change have experienced a rapid growth since 2006, and the publications are widely distributed in a large number of source journals, while the top two productive institutions are the University of East Anglia and Potsdam Institute for Climate Impact Research; (2) the cooperation at author level is on the rise, and there are closer relationships in institutional and national levels; (3) the most widely focused research topics in this field include health issues in the socioeconomic system, food security in the field of agricultural system and the issue of water resource management, etc.; (4) according to the papers from the top journals, we find that the research areas for climate change vulnerability in those publications are located in the ecological diversity, ecosystem service, water resource management and electric power supply, etc. 相似文献
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Social Ecological System (SES) is the core and highlight of the global change research and sustainability science. Based on Science Citation Index Expanded Database and China National Knowledge Infrastructure, the situation of social ecological system research was analyzed via bibliometrics from 1980 to 2017. The results indicated that: ①The scientific outcomes of social ecological system research are increasing gradually. The developed countries have greatly contributed to it, such as, Sweden and the USA, the leading countries in this field, and Stockholm University is the dominant institution on publication of SES. Cooperation between countries (regions) and institutions is strengthening gradually. ② China is one of the frontier countries in the social ecological system research with a lower increasing speed, its international cooperation and the citation frequency of publications are relatively low, and its international influence should be strengthened in the future. ③ The research highlights are listed as follows: The synergy between social ecological system integrity and social development needs, the complexity and uncertainty of SES, the mechanism between social system and its environmental factors, etc. In addition, under the stress of human activity and global climate change, the research of response and feedback mechanism of SES and policy decision-making are one of the important topics of SES. 相似文献
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月球是人类开展深空探测的首选目标,月球探测是世界各国科技竞争的制高点。开展月球科学前沿研判,对我国实施深空探测战略、规划行星科学研究路径,进而赢得未来竞争优势至关重要。基于Web of Science数据库,本文利用文献计量学方法,对月球科学领域论文产出数量、学科和期刊分布、主要国家和领先机构的竞争力、国际合作等进行了深度分析,并通过聚类分析获得当前研究热点,梳理出五大研究领域和七大前沿问题。过去20年,我国在月球科学研究取得了长足进步,但仍然存在优秀论文少、顶尖学者少、学术期刊少的问题。未来月球科学可能在三个方向上实现突破:月球的水仍将是国际月球探测和研究的重点;月球内部结构探测或是我国弯道超车的机遇;新的月球样品将进一步揭示月球形成和演化的奥秘。本研究结果可以为我国未来月球探测和研究的规划与组织提供参考。 相似文献
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Climate change is one of the most active research fields currently, which has attracted extensive attention from the international community. In order to better understand the development situation and research status of international climate change science, in this paper we took the SSCI and SCI databases as data sources, collected the relevant literatures since 1900 based on the key words related to climate change, and made some statistics and analysis of the literatures of the past one hundred years to reveal the development process of climate change research as well as the development and evolution of its research topics and hot spots. The results showed that the climate change research began in the late 18 th century and early 19 th century, and the academic debate about global warming and global cooling started in the early 1970s. The international programs and projects led by a range of international organizations and intergovernmental bodies have contributed significantly to the rapid development of climate change research. The United States and the United Kingdom have long been the core countries of climate change research. The proportion of Chinese papers has risen rapidly in the last decade. The intensity and scope of scientific research cooperation are constantly expanding. Current research focuses on climate model/modeling, climate simulation, climate policy, climate sensitivity, climate change impacts, climate change adaptation, climate change mitigation, and rate of climate change. 相似文献
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Delimitation of the continental shelf is an emerging interdisciplinary discipline in the field of international marine science and technology. It uses the scientific and technological means to expand the jurisdiction of coastal states based on the international rules of the 《United Nations Convention on the Law of the Sea》. Therefore, it is related to the marine sovereignty rights and interests of a country and also a hot topic of science and technology that all countries have competed to develop. China has launched the research in this field simultaneously with the world's maritime powers, and formed its innovative advantages in such aspects as geological models, detection techniques and delimitation systems in the delimitation of continental shelf, which have become the brand new ties for China's cooperation with foreign countries in marine science and technology, and also the important field in the maritime silk road cooperation in the 21st century. This paper introduced the basic principles and methods in the delimitation of continental shelf beyond 200 nautical miles (370 km), progress in the delimitation of the global continental shelf, and China's innovative science and technology as well as its application in maritime Silk Road cooperation, and provided the prospect of the future scientific and technological cooperation with foreign countries and development in this filed. And it was suggested China should develop the scientific and technological cooperation on the delimitation of the continental shelf along the Silk Road, promote the scientific and technological development of the delimitation of the continental shelf in China, and enhance China's influence and voice in international ocean affairs. 相似文献
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全球变化及其相关科学概念的发展与比较 总被引：3，自引：2，他引：1
在回顾全球变化科学产生和发展历史的基础上,针对当前全球变化、全球气候变化、全球环境变化、地球系统科学在概念和内涵上存在混淆的情况,就全球变化等概念的内涵、产生的过程及其联系进行了综述、分析和比较。提出全球变化是指对人类现在和未来生存与发展有重要的直接或潜在影响、由自然因素或人类因素驱动在全球范围内所发生的地球环境的变化,或与全球环境有重要关联的区域环境的变化。气候变化和全球环境变化的研究范畴包含在全球变化之中,但又各有其关注领域和交叉部分;而地球系统科学是解决全球变化问题的科学理念、思维方式和解决方案。] 相似文献
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基于文献计量的生态化学计量学文献分析 总被引：1，自引：0，他引：1
生态化学计量学已经成为国内外生态学研究的热点问题。作为一门新兴学科,科技文献能够反映科学研究的发展动态和热点变化。以Web of Science 数据库为数据源,利用专业数据分析工具TDA（Thomson Data Analyzer）和Ucinet0工具,对所有年份生态化学计量学研究相关的论文进行计量挖掘分析。结果表明：2000年以来发文量呈现直线上升趋势,且发文量较多的期刊多集中在一区、二区期刊;研究涉及多个学科领域,主要集中在环境科学与生态学、海洋与淡水生物两个学科方向。美国、德国、中国、加拿大等国家在生态化学计量学开展的研究最多,美国的亚利桑那州立大学、中国的中科院是开展研究最多的机构。国际该领域的研究热点集中在不同营养级、植物不同部位（如叶片）之间的碳、氮、磷的计量关系以及植物个体生长发育、种群增长、群落生态和生态过程的联系,尤其是对森林、草地和湿地生态系统的植物、土壤的元素计量特征。 相似文献
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Water resource is the focus and hinge between ecological environment and socio-economic development. Watershed is the basic unit of hydrology and water resource studies. It is the current hotspot in water science research to carry out the integrated research of the hydrology and water resource at the watershed scale. The Heihe River Basin is the second largest inland river basin in northwestern China, which becomes one of the hot watersheds for its unique hydrological and geographical characteristics. Based on the Web of Science Core Collection, the scientific advances achieved in the Heihe River Basin were estimated from the new sight by combining disciplinary development and problem focus, time evolution and spatial variations. The results indicated that the Heihe River Basin has made positive contribution to the world science in remote sensing, evapotranspiration, water cycle, water resources management and utilization, and climate change research in arid areas. The great achievements has promoted the Heihe River Basin up to the same levels as the international typical basins in the past 30 years, especially after the performances of the major research program entitled “Integrated Study of Eco-hydrological Processes in the Heihe River Basin” (referred to as “Heihe River Program”) supported by a grant from the National Natural Science Foundation of China and large field observation experiments. The number of published articles has ranked the top 20 in the global watershed science research. Some important scientific achievements have been obtained at the mechanisms of eco-hydrological processes in inland river basins, which can actively serve the decision making of the water resource management and sustainable development in the Heihe River Basin. The data mining and contrastive study based on bibliometrics can afford scientific reference for the watershed science research. 相似文献
19.
大气科学优先资助领域的计量学初步分析 总被引：2，自引：0，他引：2
依据对国内大气科学相关机构进行广泛调研获取的数据，以及近期国内、国际有关大气科学期刊论文数据，通过计量学方法，按照国内基础、国内热点、国际热点和国内需求四个方面从不同角度对大气科学优先资助领域进行了分析，并根据不同政策偏好设置权重对大气科学各领域进行了排序。分析表明，不论是偏重于基础研究还是偏重于应用研究，优先资助人工影响天气和大气物理领域可能会获得更大的回报；若重视科学热点、科技前沿，优先资助气候系统与全球变化和天气动力学理论与天气预报领域可能会取得更多的研究成果；若重视发展需求与科技前沿相结合，优先资助大气化学和综合探测系统领域投入资金可能会发挥更大的效益。研究结果可以为更好地了解我国大气科学发展现状，制定大气科学中长期发展战略，制定大气科学“十一五”优先资助领域战略提供一定的参考依据。 相似文献
20.
Zeng Jingjing Qu Jiansheng Pei Huijuan Dong Liping Liao Qin Liu Yanfei Zhang Zhiqiang 《地球科学进展》2015,30(11):1210-1217
The international climate change negotiation has been carried out over 20 years. The issue of climate change has shifted from a scientific question into a complex political matter which is related to the sustainable development of mankind. Based on the overview of major processes and stages of international climate conferences, this paper analyzed the key measures that major countries have taken to address climate change, as well as the primary tasks of Paris climate conference and recent international actions. The recent international climate policy issues were also analyzed in order to provide suggestions for China’s activel participation in the development of a new round of international climate change system. 相似文献