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活动构造定量研究与应用 被引量:112
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作者 邓起东 陈立春 冉勇康 《地学前缘》 EI CAS CSCD 2004年第4期383-392,共10页
自上世纪 70年代末以来 ,活动构造研究已从描述性和定性研究阶段进展到定量研究阶段 ,并主要围绕 3个方面展开工作 :(1)如何刻画活动构造的活动特征 ,即需要得到哪些活动特征定量参数 ;(2 )如何得到这些定量参数 ;(3)如何应用这些参数... 自上世纪 70年代末以来 ,活动构造研究已从描述性和定性研究阶段进展到定量研究阶段 ,并主要围绕 3个方面展开工作 :(1)如何刻画活动构造的活动特征 ,即需要得到哪些活动特征定量参数 ;(2 )如何得到这些定量参数 ;(3)如何应用这些参数进行地震危险性评价和工程安全性评价。文中就有关活动构造定量研究的这几个方面进行初步总结和分析 ,并指出在今后一段时间内 ,提高测年精度、减少研究过程各个环节的误差和不确定性 ,将是活动构造定量研究的主要发展方向。 展开更多
关键词 活动构造 定量参数 地震危险性 未来错动量
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基于潜在植被的中国陆地生态系统对气候变化的脆弱性定量评价 被引量:48
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作者 於琍 曹明奎 +4 位作者 陶波 李克让 董文杰 刘洪滨 刘长友 《植物生态学报》 CAS CSCD 北大核心 2008年第3期521-530,共10页
陆地生态系统对气候变化的响应及其脆弱性评价研究是当前全球变化领域的重要内容之一。该研究在生态系统过程模型的基础上,耦合了潜在植被对气候变化的动态响应,模拟气候变化对潜在植被分布格局和生态系统主要功能的影响,以潜在植被的... 陆地生态系统对气候变化的响应及其脆弱性评价研究是当前全球变化领域的重要内容之一。该研究在生态系统过程模型的基础上,耦合了潜在植被对气候变化的动态响应,模拟气候变化对潜在植被分布格局和生态系统主要功能的影响,以潜在植被的变化次数和变化方向定义植被分布对气候变化的敏感性和适应性,以生态系统功能特征量的年际变率及其变化趋势定义生态系统功能对气候变化的敏感性和适应性,进而对生态系统的脆弱性进行定量评价,分析不同气候条件下我国陆地生态系统的脆弱性分布格局及其区域特点。结果表明,我国自然生态系统气候脆弱性的总体特点为南低北高、东低西高,气候变化将会增加系统的脆弱性。采用政府间气候变化委员会排放情景特别报告国内和区域资源情景,即IPCC-SRES-A2气候情景进行的预测模拟表明,到21世纪末我国不脆弱的生态系统比例将减少22%左右,高度脆弱和极度脆弱的生态系统所占的比例较当前气候条件下分别减少1.3%和0.4%。气候变化对我国陆地生态系统的脆弱性分布格局影响不大。不同气候条件下,高度脆弱和极度脆弱的自然生态系统主要分布在我国内蒙古、东北和西北等地区的生态过渡带上及荒漠-草地生态系统中。总体而言,华南及西南大部分地区的生态系统脆弱性将随气候变化而有所增加,而华北及东北地区则有所减小。 展开更多
关键词 气候变化 自然生态系统 脆弱性 定量评价 CEVSA模型
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中国铜矿现状及潜力分析 被引量:35
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作者 陈建平 张莹 +5 位作者 王江霞 肖克炎 娄德波 丁建华 阴江宁 向杰 《地质学刊》 CAS 2013年第3期358-365,共8页
按照矿床模型综合地质信息矿产预测方法,在中大比例尺勘探数据的基础上,全国分省分预测工作区,对不同铜矿预测类型分别按预测深度、预测可靠程度、可利用性,圈定全国铜矿成矿远景区,并使用地质参数体积法估算全国铜矿潜在资源量。通过... 按照矿床模型综合地质信息矿产预测方法,在中大比例尺勘探数据的基础上,全国分省分预测工作区,对不同铜矿预测类型分别按预测深度、预测可靠程度、可利用性,圈定全国铜矿成矿远景区,并使用地质参数体积法估算全国铜矿潜在资源量。通过对比铜矿查明资源量等值线图与预测资源量等值线图,按照单位面积查明资源量与预测资源量来定量统计分析全国重要的铜矿资源潜力区,为铜矿的找矿勘查部署提出参考意见。 展开更多
关键词 铜矿 预测资源量 地质参数体积法 定量分析 潜力区
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安徽省宣城市特色烟种植潜力定量评价 被引量:20
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作者 季学军 王大州 +5 位作者 沈思灯 席晋峰 李德成 李贤胜 杨平 周立祥 《土壤》 CAS CSCD 北大核心 2010年第4期648-651,共4页
通过对宣城地区的自然条件、土壤条件和社会经济条件调查,利用3S技术和定量方法综合评价了安徽省宣城市种植"焦甜香"型特色烟叶的潜力。结果表明:宣城市总体上适宜种植特色烟且潜力较大,适宜面积3.84万hm2,占土地面积的3.11%... 通过对宣城地区的自然条件、土壤条件和社会经济条件调查,利用3S技术和定量方法综合评价了安徽省宣城市种植"焦甜香"型特色烟叶的潜力。结果表明:宣城市总体上适宜种植特色烟且潜力较大,适宜面积3.84万hm2,占土地面积的3.11%,其中,一等、二等、三等适宜面积分别为0.74、1.27和1.83万hm2,但各地区应采取不同的发展战略。 展开更多
关键词 定量评价 焦甜香 特色烟 适宜潜力 宜城
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Quantitative Assessment of Hydrocarbon Expulsion of Petroleum Systems in the Niuzhuang Sag, Bohai Bay Basin, East China 被引量:14
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作者 PANGXiongqi LISumei +1 位作者 JINZhijunt BAIGuoping 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第3期615-625,共11页
Based on a detailed survey of the distribution and organic geochemical characteristics of potential source rocks in the South Slope of the Niuzhuang Sag, Bohai Bay Basin, eastern China, a new approach to assess the am... Based on a detailed survey of the distribution and organic geochemical characteristics of potential source rocks in the South Slope of the Niuzhuang Sag, Bohai Bay Basin, eastern China, a new approach to assess the amount of hydrocarbons generated and expelled has been developed. The approach is applicable to evaluate hydrocarbons with different genetic mechanisms. The results show that the models for hydrocarbon generation and expulsion vary with potential source rocks, depending on thermal maturity, types of organic matter and paleoenvironment. Hydrocarbons are mostly generated and expelled from source rocks within the normal oil window. It was calculated that the special interval (algal-rich shales of the ES4 member formed in brackish environments) in the South Slope of the Niuzhuang Sag has a much higher potential of immature oil generation than the other intervals in the area. This suggests that hydrocarbons can definitely be generated in early diagenesis, especially under certain special geological settings. The proportion of hydrocarbons generated and expelled from the ES4 shales in the early diagenetic stage is up to 26.75% and 17.36%, respectively. It was also observed that laminated shales have a much higher expulsion efficiency than massive mudstones. In contrast, the special interval of the ES4 shales proposed from previous studies is probably not the whole rock for oil in the South Slope of the Niuzhuang Sag because of the small proportion of the gross volume and corresponding low percentage of hydrocarbons generated and expelled. A much lower expulsion efficiency of the source rock during the early stage relative to that within the normal oil window has been calculated. Our results indicate that the ES4 mudstones rather than the shales deposited in the Niuzhuang and Guangli Sag are the main source rocks for the oil discovered. 展开更多
关键词 Immature oil expulsion efficiency petroleum potential quantitative analysis source rock
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涠西南凹陷涠洲组构造圈闭有效性定量评价技术及应用 被引量:13
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作者 陈奎 李茂 +3 位作者 邹明生 孙晓晖 高凌 朱绍鹏 《石油学报》 EI CAS CSCD 北大核心 2018年第12期1370-1378,共9页
北部湾盆地涠西南凹陷是南海西部海域最重要的原油产区,主力含油层系涠洲组断裂发育,主要为构造圈闭。涠洲组勘探开发一体化目标的成藏关键因素为构造圈闭有效性研究,主要存在哪种圈闭形态更有利于成藏,有利圈闭潜在资源量规模两方面的... 北部湾盆地涠西南凹陷是南海西部海域最重要的原油产区,主力含油层系涠洲组断裂发育,主要为构造圈闭。涠洲组勘探开发一体化目标的成藏关键因素为构造圈闭有效性研究,主要存在哪种圈闭形态更有利于成藏,有利圈闭潜在资源量规模两方面的问题。针对这些问题,在潜力目标评价实践过程中,利用统计学方法对圈闭构造特征进行类比分析,解决哪种圈闭形态更有利于成藏的问题;提出了断层侧向封堵性与含油气性分析技术、断层垂向封堵性分析技术及油柱高度定量预测技术,提高了断层封堵性及潜在资源量的预测精度。将圈闭有效性评价技术应用于涠西南凹陷勘探开发一体化潜力目标评价实践中的效果显示,该技术提升了实际评价精度和效率,为凹陷增储上产做出了重要贡献。 展开更多
关键词 构造圈闭 圈闭有效性 定量评价 潜在资源量 涠西南凹陷
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油田储量动用状况定量描述方法 被引量:10
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作者 宋永 程保庆 杜庆龙 《大庆石油地质与开发》 CAS CSCD 北大核心 1998年第6期19-21,共3页
本文介绍了大庆多层砂岩油田、多套层系开发条件下,油田高含水后期(含水大于80%)确定储量动用状况的一种新的剩余油描述方法。应用该方法描述的剩余油潜力为油田选择性加密布井调整提供了依据。
关键词 剩余储量 储量动用 定量描述 大庆油田 油田
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提高羟基亚乙基二膦酸直接镀铜结合强度的研究 被引量:7
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作者 冯丽婷 刘清 +2 位作者 冯绍彬 胡芳红 蒋鸳鸯 《材料保护》 CAS CSCD 北大核心 2007年第9期1-3,共3页
为了提高钢铁基体上羟基亚乙基二膦酸(HEDP)镀铜层的结合强度,采用电化学工作站进行阴极极化曲线和恒电流电位-时间曲线的测定,应用弯曲折断法进行临界起始电流密度(即保证镀层结合强度的最小初始电流)的测定和镀层结合强度的定量测定,... 为了提高钢铁基体上羟基亚乙基二膦酸(HEDP)镀铜层的结合强度,采用电化学工作站进行阴极极化曲线和恒电流电位-时间曲线的测定,应用弯曲折断法进行临界起始电流密度(即保证镀层结合强度的最小初始电流)的测定和镀层结合强度的定量测定,探讨了辅助配位剂及相关工艺参数对镀层结合强度的影响。结果表明:辅助配位剂的加入提高了铜析出时的阴极极化,降低了临界起始电流密度,当用1A/dm2的电流密度进行起始电镀时,可使铁的表面在铜沉积前得到更充分的活化,使铜镀层与铁基体的结合强度提高到6416.38N/cm2,已接近铜上电镀铜的水平。介绍了电镀层结合强度的定量测定方法,探讨了提高镀层结合强度的电位活化机理。 展开更多
关键词 羟基亚乙基二膦酸 镀铜 结合强度 定量测定 电位活化
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面金属量法在香格里拉地区铜多金属矿资源潜力定量评价应用 被引量:6
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作者 卢映祥 薛顺荣 +4 位作者 肖克炎 丁建华 蒋成兴 许东 余海军 《地质与勘探》 CAS CSCD 北大核心 2010年第2期238-243,共6页
基于成矿地质背景分析和典型矿床研究,以斑岩型铜多金属矿优势矿产为目标,以出露和根据重磁、地球化学、遥感资料推测的中酸性隐伏岩体为基础,结合断裂构造,重力、航磁和遥感线性解译构造,水系沉积物测量成矿元素异常、铜矿物重砂异常... 基于成矿地质背景分析和典型矿床研究,以斑岩型铜多金属矿优势矿产为目标,以出露和根据重磁、地球化学、遥感资料推测的中酸性隐伏岩体为基础,结合断裂构造,重力、航磁和遥感线性解译构造,水系沉积物测量成矿元素异常、铜矿物重砂异常汇水盆地,定性圈定了评价矿种的45个找矿有利地段,运用面金属量法对各找矿有利地段评价矿种潜在资源量进行估算,并与该区综合成矿信息找矿预测证据权重模型圈定预测远景区对比,从量的角度提出该区铜多金属矿找矿潜力和具有大型规模远景的找矿有利地段,为生产一线矿产勘查工作部署提供定量找矿潜力科学依据。 展开更多
关键词 定量评价 资源潜力 铜多金属矿 面金属量法 香格里拉
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复杂断块油砂体剩余油分布半定量评价技术 被引量:5
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作者 郑爱玲 王新海 《石油天然气学报》 CAS CSCD 北大核心 2010年第6期127-130,共4页
复杂断块油藏由于断层的切割作用,断块小,形态各异,油水关系复杂。经过长期注水开发后,进入中高-高含水开发阶段,剩余油在空间上分布十分复杂,挖潜难度越来越大。断块油藏的复杂性,给储层建模带来很大的困难,数值模拟工作难度大,精确度... 复杂断块油藏由于断层的切割作用,断块小,形态各异,油水关系复杂。经过长期注水开发后,进入中高-高含水开发阶段,剩余油在空间上分布十分复杂,挖潜难度越来越大。断块油藏的复杂性,给储层建模带来很大的困难,数值模拟工作难度大,精确度低,难以准确描述剩余油分布。提出了基于油砂体的剩余油定性到半定量评价技术,为复杂断块油砂体剩余油预测提供了新的技术手段。该方法是在小层油砂体图编制和油砂体储量评价基础上,对油井采出量和水井注入量进行劈分,将采出量和注入量落实到油砂体,以此为基础对油砂体的注采状况进行分析,明确油砂体的采出程度、总体水淹程度,确定油砂体内部水淹差异状况,编制油砂体水淹图,半定量表征水淹特征,定性-半定量指出油砂体内剩余潜力的纵向和平面分布,为油田进行下步综合治理提供依据。 展开更多
关键词 复杂断块 油砂体 剩余油 水淹图 半定量 开发潜力
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Introgression of Two Drought QTLs into FUNAABOR-2 Early Generation Backcross Progenies Under Drought Stress at Reproductive Stage 被引量:3
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作者 Christian Okechukwu ANYAOHA Mamadou FOFANA +2 位作者 Vernon GRACEN Pangirayi TONGOONA Semon MANDE 《Rice science》 SCIE CSCD 2019年第1期32-41,共10页
FUNAABOR-2 is a popular Ofada rice variety grown in a large area under rainfed upland condition across western states of Nigeria. We used the combination of phenotypic and marker-assisted selection(MAS) to improve gra... FUNAABOR-2 is a popular Ofada rice variety grown in a large area under rainfed upland condition across western states of Nigeria. We used the combination of phenotypic and marker-assisted selection(MAS) to improve grain yield of FUNAABOR-2 under drought stress(DS) at the reproductive stage via introgression of two drought quantitative trait loci(QTLs), qDTY12.1 and qDTY2.3. Foreground selection was carried out using peak markers RM511 and RM250, associated with qDTY12.1 and qDTY2.3, respectively, followed by recombinant selection with RM28099 and RM1261 distally flanking qDTY12.1. Furthermore, BC1 F2-derived introgressed lines and their parents were evaluated under DS and non-stress(NS) conditions during the 2015–2016 dry season. Overall reduction of grain yield under DS compared to NS was recorded. Introgressed lines with qDTY12.1 and qDTY2.3 combinations showed higher yield potential compared to lines with single or no QTL under DS, indicating significant positive interactions between the two QTLs under the FUNAABOR-2 genetic background. Pyramiding of qDTY12.1 and qDTY2.3 in the FUNAABOR-2 genetic background led to higher grain yield production under DS and NS. 展开更多
关键词 DROUGHT foreground selection introgressed line peak marker yield potential rice quantitative TRAIT locus
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济南市济阳区农用地整理潜力分析 被引量:2
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作者 范恺悦 《山东国土资源》 2020年第12期70-74,共5页
农用地整理潜力作为农用地整理项目选取和项目时序安排的基础,在新形势下的国土空间综合整治规划中有重要的现实意义。本文以济南市济阳区为研究对象,在济阳区耕地质量更新评价成果和2017年济阳区土地利用现状成果基础上,运用arcgis,sps... 农用地整理潜力作为农用地整理项目选取和项目时序安排的基础,在新形势下的国土空间综合整治规划中有重要的现实意义。本文以济南市济阳区为研究对象,在济阳区耕地质量更新评价成果和2017年济阳区土地利用现状成果基础上,运用arcgis,spss等分析软件,运用统计分析方法分析济阳区数量潜力,运用产能核算方法分析其质量潜力,通过几何平均法对济阳区各乡镇(街道)潜力评价结果进行了分级。结果表明:济阳区平均新增耕地系数为0.28%,共划分为5个潜力区,以二级、三级为主。 展开更多
关键词 农用地整理 数量潜力 质量潜力 综合潜力 济南市济阳区
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Comparison of potentials between genotype-based selection and genotypic value-based selection of quantitative traits 被引量:1
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作者 Weiren Wu Yuanchang Zhou Weiming Li 《Chinese Science Bulletin》 SCIE EI CAS 2002年第24期2080-2083,共4页
According to the difference of selection criteria, methods of marker-assisted selection (MAS) of quantitative traits can be divided into genotype-based selection (GS) and genotypic value-based selection (GVS). By mean... According to the difference of selection criteria, methods of marker-assisted selection (MAS) of quantitative traits can be divided into genotype-based selection (GS) and genotypic value-based selection (GVS). By means of computer simulation, potentials of the two methods were compared. Results showed that the two methods had similar basic laws and their efficiencies were not significantly different except that GS behaved better in the case where the number of QTLs was large and QTL effects were equal. From the application point of view, combination of GS and GVS should be the development direction of MAS research in the future. 展开更多
关键词 quantitative TRAIT marker-assisted SELECTION genotypebased SELECTION GENOTYPIC value-based SELECTION potential.
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Simulation of Potential Production and Optimum Population Quantitative Indices for the Second Hybrid Rice 被引量:1
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作者 YAN Li-Jiao YAO Zhong ZHENG Zhi-ming LI Hua-bin 《Agricultural Sciences in China》 CAS CSCD 2006年第7期498-505,共8页
The article established the HDRICE model by modifying the structure of the ORYZA1 model and revising its parameters by field experiments. The HDRICE model consists of the modules of morphological development of rice, ... The article established the HDRICE model by modifying the structure of the ORYZA1 model and revising its parameters by field experiments. The HDRICE model consists of the modules of morphological development of rice, daily dry matter accumulation and partitioning, daily CO2 assimilation of the canopy, leaf area, and tiller development. The model preferably simulated the dynamic rice development because of the thorough integration of the effects of temperature and light on the rates of rice development, photosynthesis, respiration, and. other ecophysiological processes. In addition, this model has attainable grain yield in the test experiment that showed the potential yield of cultivar Xieyou 46 ranged from 11 to 13 tons ha-~. Besides, the model was used to optimize the combinations of the transplanting date, seedling age and density for cultivar Xieyou 46 at Jinhua area, and the population quantitative indices to attain the potential yield such as maximum stems, effective panicles, filled grain number/leaf area, and so on. The result showed that the combination of transplanting date on July 25, seedling age of 35 days and base seedling density of 1.33 x 106ha-1 is the optimum combination for the second hybrid rice production in Jinhua County, China. And the maximum stems, the effective panicles, the filled grain per panicle, the peak of optimum LAI, LAI in later filling stage, and the filled grain number/leaf were 6.03×10^6ha, 3.99×10^6ha, 119.2, 8.59, 5-6, and 0.64, respectively. 展开更多
关键词 SIMULATION MODEL potential production optimum population quantitative indices second hybrid rice
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气象科学历史特质解析及学科意义 被引量:1
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作者 陈正洪 《咸阳师范学院学报》 2019年第6期76-81,共6页
气象科技史与其他自然科学史相比,有其独特之处。国际气象科技史经历了从思辨到定量分析的发展过程,中国气象科技史有本土文化和地域特色。厘清中外气象科技史的差异,是气象科技史发展需要解决的基本问题,在科学技术史学科体系内也具有... 气象科技史与其他自然科学史相比,有其独特之处。国际气象科技史经历了从思辨到定量分析的发展过程,中国气象科技史有本土文化和地域特色。厘清中外气象科技史的差异,是气象科技史发展需要解决的基本问题,在科学技术史学科体系内也具有特殊的价值和发展意义。 展开更多
关键词 气象科技史 中外差异 定量分析 本土性 潜在价值
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Effect of Wei’s triple nine needling therapy on flash visual evoked potentials in rats with traumatic optic neuropathy
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作者 Shi-Meng Li Jian Zhou +5 位作者 Qi-Ping Wei Jun Wang Wu Sun Yan Wang Jie Wang Yan-Ting Xia 《Journal of Hainan Medical University》 2022年第12期7-12,共6页
Objective:To investigate the effect of Wei’s triple nine needling therapy on the N2-P2 wave of the flash visual evoked potential(FVEP)in rats of the of the transverse directional pulling model.Methods:Thirty-six Wist... Objective:To investigate the effect of Wei’s triple nine needling therapy on the N2-P2 wave of the flash visual evoked potential(FVEP)in rats of the of the transverse directional pulling model.Methods:Thirty-six Wistar rats were randomly grouped,nine were in normal control group without any treatment,and the remaining 27 were surgically modelled in the right eyes.Eighteen of these rats were randomly divided into a Wei’s triple nine needling therapy group and a model group of nine rats each after the TON model was made using the transverse quantitative retraction method.The other 9 rats were sham-operated,and only the optic nerve was exposed without retraction.On the next day of modelling,the Wei’s triple nine needling therapy group was treated with Wei’s triple nine needling therapy for 20 minutes/1 time/1 day for 14 days.The model group,sham-operated group and normal control group were not intervened.Wei's triple nine acupoints were represented as follows:1st link:"Jingming"(BL1)and"Chengqi"(ST1);2nd link:"Sizhukong"(SJ23)penetrating"Taiyang"(EX-HN5);and the third:"Fengchi"(GB 20)and"Taichong"(LV3).The FVEP of each group was observed on 1d,7d and 14d.The FVEP of each group was observed on 1d,7d and 14d.Results:Compared with the model group,the N2 wave latency and P2 wave latency were shortened in the Wei’s triple nine needling therapy on 1d(P<0.05,P<0.01);on 7d,their N2 wave latency was shortened(P<0.01)and the N2-P2 wave amplitude was increased compared with the model group(P<0.05);on 14d,their P2 wave latency was shortened(P<0.05)and the N2-P2 wave amplitude was increased.There was no statistical difference in N2 wave latency,P2 wave latency and N2-P2 wave amplitude in the sham-operated group on 1d,7d and 14d(P>0.05).The delayed N2 and P2 wave latencies in the model group did not improve from 1d to 14d(P>0.05)and the amplitude decreased throughout,showing a significant difference on 14d compared to 1d(P<0.05).In contrast,the N2 wave latency in Wei’s triple nine needling therapy group was not signif 展开更多
关键词 Wei’s triple nine needling therapy Traumatic optic neuropathy Transverse quantitative traction method Flash visual evoked potential Rat
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农用地整理潜力测算与分级研究——以延边朝鲜族自治州为例
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作者 姬冬梅 李淑杰 《东北师大学报(自然科学版)》 北大核心 2021年第3期107-114,共8页
以延边朝鲜族自治州(简称延边州)各乡镇为评价单元,运用多因素综合评价法、层次分析法(AHP)、系统聚类等方法建立综合评价模型.以ArcGIS10.2,SPSS19.0为平台,确定延边州各乡镇农用地整理潜力的大小及空间分布情况,分析了农用地整理潜力... 以延边朝鲜族自治州(简称延边州)各乡镇为评价单元,运用多因素综合评价法、层次分析法(AHP)、系统聚类等方法建立综合评价模型.以ArcGIS10.2,SPSS19.0为平台,确定延边州各乡镇农用地整理潜力的大小及空间分布情况,分析了农用地整理潜力的影响因素.结果表明:延边州农用地整理潜力很大,可新增耕地面积117.77 km^(2),产能提高潜力达4.75×10^(8)kg.全州共分为4个潜力区域,其中,龙井市老头沟镇属于Ⅰ级潜力区,农用地整理数量潜力和质量潜力均为全州最大.延边州应根据测算结果有重点、分区域地提升耕地质量等级、优化耕地布局. 展开更多
关键词 农用地整理 数量潜力 质量潜力 潜力分区 延边州
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Artificial Neural Network Method Based on Expert Knowledge and Its Application to Quantitative Identification of Potential Seismic Sources
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作者 Hu Yinlei and Zhang YumingInstitute of Geology,SSB,Beijing 100029,China 《Earthquake Research in China》 1997年第2期64-72,共9页
In this paper,an approach is developed to optimize the quality of the training samples in the conventional Artificial Neural Network(ANN)by incorporating expert knowledge in the means of constructing expert-rule sampl... In this paper,an approach is developed to optimize the quality of the training samples in the conventional Artificial Neural Network(ANN)by incorporating expert knowledge in the means of constructing expert-rule samples from rules in an expert system,and through training by using these samples,an ANN based on expert-knowledge is further developed.The method is introduced into the field of quantitative identification of potential seismic sources on the basis of the rules in an expert system.Then it is applied to the quantitative identification of the potential seismic sources in Beijing and its adjacent area.The result indicates that the expert rule based on ANN method can well incorporate and represent the expert knowledge in the rules in an expert system,and the quality of the samples and the efficiency of training and the accuracy of the result are optimized. 展开更多
关键词 Artificial Neural Network Method Based on Expert Knowledge and Its Application to quantitative Identification of potential Seismic Sources LENGTH
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Evidence of potential change in nonsequential double ionization
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作者 Changchun Jia Pu Zhang +1 位作者 Hua Wen Zhangjin Chen 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第2期262-267,共6页
Recently,the quantitative rescattering model(QRS)for nonsequential double ionization(NSDI)is modified by taking into account the potential change(PC)due to the presence of electric field at the time of recollision.Usi... Recently,the quantitative rescattering model(QRS)for nonsequential double ionization(NSDI)is modified by taking into account the potential change(PC)due to the presence of electric field at the time of recollision.Using the improved QRS model,we simulate the longitudinal momentum distributions of doubly charged ions He2+by projecting the correlated two-electron momentum distributions for NSDI of He onto the main diagonal.The obtained results are compared directly with the experimental data at different intensities.It is found that when the PC is considered,the width of momentum distributions reduces and the agreement between theory and experiment is improved. 展开更多
关键词 nonsequential double ionization quantitative rescattering model potential change momentum distribution of doubly charged ion
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干酪根类型及生烃潜力确定新方法 被引量:29
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作者 熊德明 马万云 +2 位作者 张明峰 吴陈君 妥进才 《天然气地球科学》 EI CAS CSCD 北大核心 2014年第6期898-905,共8页
干酪根是由千差万别的原始有机物质经过生化作用和物化作用改造而成,它们彼此之间的化学组成、内部结构、形状及大小各不相同。对于干酪根类型的划分,目前存在很多方法,如三分法、四分法、五分法和"X"图解等,最常用的是Tisso... 干酪根是由千差万别的原始有机物质经过生化作用和物化作用改造而成,它们彼此之间的化学组成、内部结构、形状及大小各不相同。对于干酪根类型的划分,目前存在很多方法,如三分法、四分法、五分法和"X"图解等,最常用的是Tissot的三分法。虽然有这么多的分类方法,但是无法对干酪根类型进行准确定量分析。因此,在四型分类法的基础上提出了新的定量分析方法。拟合"Van Kerevenlen"图版上4种类型曲线方程,然后计算目标点到4种类型曲线的距离,从而确定干酪根类型(到哪条曲线的距离值最小,目标点就属于该型的干酪根)。采用新建立的干酪根生烃潜力指数确定干酪根的生烃潜力。通过对比分析干酪根类型和生烃潜力的计算结果,研究发现,新建立数值化方法的结果和生烃潜力计算结果基本吻合,说明新的数值化类型确定方法是正确的、可靠的。并且具有计算速度快、精度高、计算范围大、计算机操作方便等多方面的特点。 展开更多
关键词 干酪根类型 定量分析 最小二乘法 “Van Kerevenlen”图版 干酪根四分法 生烃潜力
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