检索结果-南通市图书馆

基于Lorenz模型的集合预报与单一预报的比较研究

在线全文

学校读者我要写书评

暂无评论

物理学报 2018年第7期67卷 60-68页

作者：梁丁顾斌丁瑞强李建平钟权加南京信息工程大学空间天气研究所南京210044 中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室北京100029 南京信息工程大学物理与光电工程学院南京210044 北京师范大学全球变化与地球系统科学研究院北京100875

根据非线性局部Lyapunov向量方法和增长模繁殖方法,选取Lorenz63模型和Lorenz96模型的不同状态为例,对集合预报与单一预报的预报技巧开展了对比研究.结果表明:与单一预报比较,集合预报的均方根误差和型异常相关有明显改善,随预报时间推... 详细信息

根据非线性局部Lyapunov向量方法和增长模繁殖方法,选取Lorenz63模型和Lorenz96模型的不同状态为例,对集合预报与单一预报的预报技巧开展了对比研究.结果表明:与单一预报比较,集合预报的均方根误差和型异常相关有明显改善,随预报时间推移,改善效果越显著,且集合平均优于单一预报的实验个例数逐渐增多.就概率分布(f)而言,单一预报状态的f与真实状态基本一致,不随时间变化;而集合平均预报状态的f则随时间呈现出值域变窄、峰值变大的特点.表明随预报时间的延长,单一预报状态为混沌吸引子上的随机状态,而集合平均预报状态为吸引子子集上的随机状态,这可能是集合平均误差小于单一预报的原因.

关键词：非线性局部Lyapunov向量集合预报单一预报 Lorenz模型

Synthesis,Crystal Structures and Luminescent Properties of Pb(Ⅱ),Sr(Ⅱ) Coordination Polymers Constructed by 5-methyl-1H-pyrazole-3-carboxylic acid

在线全文

学校读者我要写书评

暂无评论

Synthesis,Crystal Structures and Luminescent Properties of P...

基于空间分析的机井管理系统总体设计及其关键技术探讨

中国化学会第六届全国结构化学学术会议

作者： Wei Han,Xiaoyan Jia,Linti Chen,Jingtin Bao,Mei-Ling Cheng,Qi Liu~* School of Petrochemical Engineering and Jiangsu Province key laboratory of Fine Petro-chemical Technology,Changzhou University,Changzhou 213164,Jiangsu

At present,much attention has been focused on the metal-organic heterocyclic carboxylic acid coordination polymers,due to their potential applications such as gas adsorption,separation,optics, catalysis and informatio...

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

水文地质工程地质 2004年第1期31卷 101-104页

作者：赵祥张晔刘素红北京师范大学资源环境系遥感与GIS研究中心北京100875 天津市龙脉水资源咨询中心天津300060

在GIS空间分析技术支持下 ,对机井管理系统从总体设计、系统功能结构、数据库建库方法、系统实现等多方面进行了阐述 ,并探讨了系统开发的关键技术和主要的程序编码 ,在机井管理信息化方面进行了有益的尝试 ,为建立类似系统提供了一个... 详细信息

在GIS空间分析技术支持下 ,对机井管理系统从总体设计、系统功能结构、数据库建库方法、系统实现等多方面进行了阐述 ,并探讨了系统开发的关键技术和主要的程序编码 ,在机井管理信息化方面进行了有益的尝试 ,为建立类似系统提供了一个应用范例。

关键词：空间分析机井管理系统设计数据库总体设计管理信息化地下水资源管理

在线全文

学校读者我要写书评

暂无评论

西北省区旅游资源开发刍议

首都师范大学学报（自然科学版） 2001年第4期22卷 88-95页

作者：张锋北京市环境保护局

提出旅游资源开发的理论依据、原则 ,并用于分析西北省区部分旅游景区 ,发现存在的问题。

关键词：西北省区旅游资源旅游开发旅游景区开发原则历史遗迹

An Approach for Face Recognition Based on Fusion of DTCWT and Manifold Regularized Orthogonal Discriminant Analysis

在线全文

学校读者我要写书评

暂无评论

An Approach for Face Recognition Based on Fusion of DTCWT an...

The Optimization of GIS Shortest Path Inquires Based on Dijkstra

2009中国控制与决策会议

作者： Qiang Zhang~1,Yunze Cai~1,Xiaoming Xu~(1,2,3) 1.School of Electric and information Engineering,Shanghai Jiaotong University,Shanghai 200240 2.University of Shanghai for science and technology,Shanghai 200093 3.Shanghai Academy of Systems Science,Shanghai 200093

＜正＞In this paper,a novel subspace learning method called Manifold Regularized Orthogonal Discriminant Analysis（MRODA） is first *** on within-class local geometry preservation and Least Square regression framework for LDA,MRODA can encode both the local geometry and discriminant structures of face data manifolds, and can address the small sample size problem through pseudo-inverse *** transform vectors are orthogonalized to improve their discriminatory *** on the selected Dual-Tree Complex Wavelet Transform features,an approach for face recognition based on the fusion of spatial and frequency features is developed. Experimental results on ORL,Yale and AR face databases show the effectiveness of the proposed approach.

关键词： Face Recognition Manifold Regularized Orthogonal Discriminant Analysis Dual-Tree Complex Wavelet Feature Selection information Fusion

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

The Optimization of GIS Shortest Path Inquires Based on Dijk...

security Framew ork of Mobile Internet

2011 International Conference on Management Science and Intelligent Control(ICMSIC 2011)

作者： Cai Yi South china University of Technology SCUT Guangzhou china Zhu Juan South china University of Technology SCUT Guangzhou china

path-finding is one of the key application problems in Geographical information *** problem can be attributed to essentially the shortest path algorithm of network *** paper proposes an improved model based on Dijkstra *** method covers the shortage of extremely low efficiency of Dijkstra algorithm when processing mass data of the nodes and ***,according to the characteristics of geographical information system on the search optimization,this algorithm model greatly improves the searching success rate and *** testing in a real city road network example,it proved that by given origin and destination,the method in this paper can rapidly,effectively,accurately find the route,highlighted render it and display.

关键词： component Geographical information systems Dijkstra algorithm The shortest path Layered acceleration

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

ZTE Communications 2009年第4期7卷 31-34页

作者： Wei Liang (china Academy of Telecommunication Research of MIIT, beij.ng 100045 , P . R . china )

The article describes the layered model of physical network and information security, and the establishment of the mobile Internet’s security framework based on its network architecture. The mobile Internet has three parts, i.e. terminal, network and service system, each of which can be studied in four layers of the network and information security, namely, the equipment/environment security layer, the service and application security layer, the information security layer and the information content security layer.

关键词： security Framew ork of Mobile Internet work mode

关于“建设内蒙古北方生态安全屏障,保障国家生态安全”的调研报告

在线全文

学校读者我要写书评

暂无评论

中国发展 2024年第1期24卷 65-70页

作者：致公党中央环境与可持续发展委员会高吉喜冯朝阳中国致公党中央委员会北京100120 不详

习近平总书记指出,筑牢我国北方重要生态安全屏障,是内蒙古必须牢记的“国之大者”。近年来,内蒙古自治区坚决扛起政治责任,持续增强筑牢我国北方重要生态安全屏障的思想自觉和行动自觉,不断创新思路举措,坚持从严从快,全面抓好各类生... 详细信息

习近平总书记指出,筑牢我国北方重要生态安全屏障,是内蒙古必须牢记的“国之大者”。近年来,内蒙古自治区坚决扛起政治责任,持续增强筑牢我国北方重要生态安全屏障的思想自觉和行动自觉,不断创新思路举措,坚持从严从快,全面抓好各类生态环境问题整改,我国北方重要生态安全屏障建设取得阶段性成效。但也存在着重点区域生态建设尚需强化、生态环境整治难度较大、水资源供需矛盾突出、绿色低碳转型面临较大挑战、造林成本增加后续管护资金不足等问题。为此,建议:充分认识内蒙古北方生态屏障建设对保障国家生态安全的重要作用和意义;以“三屏三源三廊一弯”为重点打造内蒙古生态屏障建设总格局;科学确定内蒙古北方生态屏障建设的主要任务;落实习近平总书记有关指示批示,全方位筑牢北方生态安全屏障。

关键词：内蒙古北方生态安全屏障国家生态安全

Performance and Inheritance of Rice Starch RVA Profile Characteristics

在线全文

学校读者我要写书评

暂无评论

Rice science 2005年第1期12卷 39-47页

作者： YANChang-jie LIXin ZHAngRong SUIJiong-ming LIAngGuo-hua SHENXin-ping GuShi-liang GuMing-hong ThekeylaboratoryofEducationMinistryforPlantFunctionalGenomics YangzhouUniversityYangzhou225009China

The classification and inheritance of rice starch RVA profiles were studied by testing RVA profiles of F2 clonally propagated population and some varieties, including japonica, indica, and glutinous types. All the RVA profiles of accessions could be divided into six kinds based on the cluster analysis, that is A, B, C, D, E and F. Feature profile of sticky variety was type A. The profiles of indica varieties could be presented as B, C, D, E and F types and that of japonica varieties fell into D, E and F *** profiles of the rice were mainly affected by apparent amylose content (AAC), but the difference of RVA profiles could also be detected in the varieties with similar AAC. The close relationship between RVA profile indices and sensory of low or middle AAC varieties suggested that the RVA profiles can be used as indirect index to evaluate eating and cooking quality. In four hybrid combinations, the component indices of RVA profiles of F1 were between those of its parents except peak viscosity and pasting temperature. Also, in F2 clonally propagated population, all the components of the RVA profiles showed continuous segregation,suggesting that all of them were controlled by a series of minor genes, although Wx gene may play an important role in determining the RVA profiles. These results may provide some new information useful for rice quality breeding program.

关键词： rice RVA profiles apparent amylose content eating quality F2 clonally propagated population