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Application of Statistical Tools for Data Analysis and Interpretation in Rice Plant Pathology 被引量:2
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作者 Parsuram NAYAK Arup Kumar MUKHERJEE +1 位作者 Elssa PANDIT Sharat Kumar PRADHAN 《Rice science》 SCIE CSCD 2018年第1期1-18,共18页
There has been a significant advancement in the application of statistical tools in plant pathology during the past four decades. These tools include multivariate analysis of disease dynamics involving principal compo... There has been a significant advancement in the application of statistical tools in plant pathology during the past four decades. These tools include multivariate analysis of disease dynamics involving principal component analysis, cluster analysis, factor analysis, pattern analysis, discriminant analysis, multivariate analysis of variance, correspondence analysis, canonical correlation analysis, redundancy analysis, genetic diversity analysis, and stability analysis, which involve in joint regression, additive main effects and multiplicative interactions, and genotype-by-environment interaction biplot analysis. The advanced statistical tools, such as non-parametric analysis of disease association, meta-analysis, Bayesian analysis, and decision theory, take an important place in analysis of disease dynamics. Disease forecasting methods by simulation models for plant diseases have a great potentiality in practical disease control strategies. Common mathematical tools such as monomolecular, exponential, logistic, Gompertz and linked differential equations take an important place in growth curve analysis of disease epidemics. The highly informative means of displaying a range of numerical data through construction of box and whisker plots has been suggested. The probable applications of recent advanced tools of linear and non-linear mixed models like the linear mixed model, generalized linear model, and generalized linear mixed models have been presented. The most recent technologies such as micro-array analysis, though cost effective, provide estimates of gene expressions for thousands of genes simultaneously and need attention by the molecular biologists. Some of these advanced tools can be well applied in different branches of rice research, including crop improvement, crop production, crop protection, social sciences as well as agricultural engineering. The rice research scientists should take advantage of these new opportunities adequately in adoption of the new highly potential advanced technologies while planning experimental designs, data collection, analysis and interpretation of their research data sets. 展开更多
关键词 statistical tool PLANT PATHOLOGY data ANALYSIS multivariate ANALYSIS NON-PARAMETRIC ANALYSIS MICRO-ARRAY ANALYSIS decision theory PLANT disease EPIDEMICS rice
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Developing a Data Modelling Tool to Visualize the Transformation of an ER Diagram into a Relational Schema
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作者 Elitsa Silyanova Arsova Silyan Sibinov Arsov 《Computer Technology and Application》 2012年第3期201-205,共5页
In this paper, the authors present the development of a data modelling tool that visualizes the transformation process of an "Entity-Relationship" Diagram (ERD) into a relational database schema. The authors' foc... In this paper, the authors present the development of a data modelling tool that visualizes the transformation process of an "Entity-Relationship" Diagram (ERD) into a relational database schema. The authors' focus is the design of a tool for educational purposes and its implementation on e-learning database course. The tool presents two stages of database design. The first stage is to draw ERD graphically and validate it. The drawing is done by a learner. Then at second stage, the system enables automatically transformation of ERD to relational database schema by using common rules. Thus, the learner could understand more easily how to apply the theoretical material. A detailed description of system functionalities and algorithm for the conversion are proposed. Finally, a user interface and usage aspects are exposed. 展开更多
关键词 E-learning course data modelling tool entity-relationship model relational model.
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6 Top Tools for Taming Big Data
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作者 JakoB BJ orklund 《机械设计与制造工程》 2012年第4X期54-56,共3页
The industry now has a buzzword, 'big data,' for how we’re going to do something with the huge amount of information piling up. 'Big data' is replacing
关键词 HADOOP Top tools for Taming Big data Hive STUDIO data
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The Application of the GM(1,1) Metabolism Model to Error Data Processing of NC Machine Tools 被引量:1
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作者 LIAODe-gang XIONGXiao-hong 《International Journal of Plant Engineering and Management》 2003年第2期103-107,共5页
This paper applied the gray system theory to error data processing of NCmachine tools according to the characteristic. It presented the gray metabolism model of error dataprocessing. The test method for the model need... This paper applied the gray system theory to error data processing of NCmachine tools according to the characteristic. It presented the gray metabolism model of error dataprocessing. The test method for the model needs less capacity. Practice proved that the method issimple, calculation is easy, and results are exact. 展开更多
关键词 NC machine tools gray system ERROR data processing
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Exploration of University English Teachers’Acceptance and Willingness to Use Learning Management System Data Analysis Tools
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作者 Xiaochao Yao 《Journal of Contemporary Educational Research》 2024年第9期120-128,共9页
This study investigates university English teachers’acceptance and willingness to use learning management system(LMS)data analysis tools in their teaching practices.The research employs a mixed-method approach,combin... This study investigates university English teachers’acceptance and willingness to use learning management system(LMS)data analysis tools in their teaching practices.The research employs a mixed-method approach,combining quantitative surveys and qualitative interviews to understand teachers’perceptions and attitudes,and the factors influencing their adoption of LMS data analysis tools.The findings reveal that perceived usefulness,perceived ease of use,technical literacy,organizational support,and data privacy concerns significantly impact teachers’willingness to use these tools.Based on these insights,the study offers practical recommendations for educational institutions to enhance the effective adoption of LMS data analysis tools in English language teaching. 展开更多
关键词 Learning management system data analysis tools Technology acceptance University English teachers Educational technology data privacy concerns
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A Functional Data Modeling Tool for Engineering Applications
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作者 来可伟 《High Technology Letters》 EI CAS 1999年第1期42-48,共7页
The fact that most engineering applications are developed by engineers themselves rather than computer professionals calls for the data modeling methods to be powerful enough to represent complex engineering phenomena... The fact that most engineering applications are developed by engineers themselves rather than computer professionals calls for the data modeling methods to be powerful enough to represent complex engineering phenomena, but simple enough to use. A data modeling method which can help engineers to write C++ code with high quality is introduced. 展开更多
关键词 data MODELING System analysis and design SOFTWARE ENGINEERING tool
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Design and Implementation of GUSNI 1.1: VI Tool for WSN Data Monitoring Applications
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作者 Roop Pahuja Harish Kumar Verma Moin Uddin 《通讯和计算机(中英文版)》 2011年第7期550-559,共10页
关键词 应用工具 审美设计 WSN 数据监控 VI 网络数据包 状态监测 ZIGBEE
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刀具柱面Data Matrix码几何畸变的仿真分析 被引量:4
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作者 李夏霜 何卫平 +2 位作者 雷蕾 王伟 林清松 《上海交通大学学报》 EI CAS CSCD 北大核心 2012年第9期1349-1354,共6页
分析了刀具柱面Data Matrix(DM)码几何畸变的原理与过程,利用透视投影的方法建立了柱面DM码的几何畸变模型并对其进行仿真.结果表明,该模型较好地模拟了DM码在刀具柱面的几何畸变状况.通过仿真分析,获得了在一定曲率柱面上标刻DM码的合... 分析了刀具柱面Data Matrix(DM)码几何畸变的原理与过程,利用透视投影的方法建立了柱面DM码的几何畸变模型并对其进行仿真.结果表明,该模型较好地模拟了DM码在刀具柱面的几何畸变状况.通过仿真分析,获得了在一定曲率柱面上标刻DM码的合适尺寸以及采集过程中相机的合适几何参数. 展开更多
关键词 刀具柱面 data Matrix码 透视投影 几何畸变 仿真
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基于旋转采集Data Matrix码序列图像拼接方法 被引量:1
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作者 林清松 何卫平 +2 位作者 雷蕾 王伟 李夏霜 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2013年第5期631-638,645,共9页
针对刀具柱面Data Matrix码图像拼接的特殊需求,已有算法拼接结果识读率低、实时性差的缺陷,提出了一种基于Data Matrix码图像特征的拼接方法.该方法基于缝隙内旋转采集的刀具柱面Data Matrix码序列图像,通过条码纵向位移校正与模块划分... 针对刀具柱面Data Matrix码图像拼接的特殊需求,已有算法拼接结果识读率低、实时性差的缺陷,提出了一种基于Data Matrix码图像特征的拼接方法.该方法基于缝隙内旋转采集的刀具柱面Data Matrix码序列图像,通过条码纵向位移校正与模块划分,完成基于模块信息的最小欧氏距离图像粗配准和归一化互相关图像精配准;为了保证条码结构正确,消除无重合区域对图像拼接的影响,根据匹配度先将序列图像融合成3部分并校正畸变;最后将这3部分按条码模块关系融合成一幅尺寸正确的图像,实现了条码定位、模块划分,以方便后续进行解码.实验结果表明,文中方法能够满足刀具柱面Data Matrix码序列图像的拼接需求,拼接结果解码正确率达到96%,拼接时间小于250ms,并且大大提高了解码速度. 展开更多
关键词 刀具柱面 data Matrix码 图像拼接 图像配准 图像融合
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基于Geodatabase数据模型和Case工具设计实现配电GIS数据库 被引量:7
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作者 冯晓良 徐学军 +1 位作者 胡森 韩云 《继电器》 CSCD 北大核心 2007年第10期59-63,共5页
传统的地理信息系统数据模型难以表达非结构化数据和GIS中具有复杂结构的数据,也不能表达继承、聚合等在GIS中广泛使用的关系。文章概述了Geodatabase模型的结构和特点,并针对配电网数据结构的特点,在Geodatabase模型的基础上,利用UML... 传统的地理信息系统数据模型难以表达非结构化数据和GIS中具有复杂结构的数据,也不能表达继承、聚合等在GIS中广泛使用的关系。文章概述了Geodatabase模型的结构和特点,并针对配电网数据结构的特点,在Geodatabase模型的基础上,利用UML建模语言和ArcGIS提供的Case工具,设计并实现了配电GIS数据库。这种数据模型和设计方法比传统方法直观、简单且易于修改,对配电网的描述更贴切,利于数据库设计的优化,是设计空间数据库的一种较好的方法。 展开更多
关键词 Geodatabase数据模型 UML CASE工具 配电网数据库
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基于HBase和GeoTools的矢量空间数据存储模型研究 被引量:15
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作者 郑坤 付艳丽 《计算机应用与软件》 CSCD 2015年第3期23-26,共4页
针对非结构化数据库HBase存储技术的研究,提出一种矢量空间数据存储模型,对现有的矢量空间数据格式进行转换存储,以解决云存储技术缺乏空间数据拓扑关系描述及不能直接存储矢量空间数据的问题。该模型利用了列模式和key/value映射的稀... 针对非结构化数据库HBase存储技术的研究,提出一种矢量空间数据存储模型,对现有的矢量空间数据格式进行转换存储,以解决云存储技术缺乏空间数据拓扑关系描述及不能直接存储矢量空间数据的问题。该模型利用了列模式和key/value映射的稀疏存储机制,并采用基于GeoTools中间件的思想对矢量空间数据展示其空间拓扑关系。在HBase集群上的实验表明,该模型克服了HBase存储技术在矢量空间数据存储方面的瓶颈,在其体现空间拓扑关系的前提下,对矢量空间数据可以直接存取和展示,提高了空间数据存储效率。 展开更多
关键词 矢量数据存储模型 HBASE Geotools
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五维分析模型下中国数据要素交易政策的演进研究
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作者 杜宝贵 丰佰恒 《东北大学学报(社会科学版)》 北大核心 2026年第1期76-86,140,共12页
为建设统一、专业、有序的数据要素交易市场,从发展的视角结合“类型、主体、再生、工具、主题”等维度,对国务院及各部委所颁发的148项数据要素交易政策进行了计量分析,总结了数据要素交易政策演进逻辑,分析了数据要素交易市场建设面... 为建设统一、专业、有序的数据要素交易市场,从发展的视角结合“类型、主体、再生、工具、主题”等维度,对国务院及各部委所颁发的148项数据要素交易政策进行了计量分析,总结了数据要素交易政策演进逻辑,分析了数据要素交易市场建设面临的现实困境,提出数据要素交易政策的优化路径。研究表明,中国数据要素交易政策存在法律设计滞后、责任主体偏位、复制性再生凸显、工具选择失衡、主题关注宏观划一等问题,并提出了以下政策优化建议:以强化交易法律为抓手,为数据要素交易提供纲领性遵循;以多元政策主体为引擎,为协同发展供应全态性动力;以细化政策再生为突破,为数据要素交易指明战略性方向;以均衡政策工具为保障,为数据要素交易作出基础性引领;以多样政策主题为基石,为数据要素交易提供制度性依据。 展开更多
关键词 数据要素 数据要素交易政策 政策再生 政策主题 政策工具
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面向刀具异常检测的多模态时序融合网络
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作者 盖田田 黄民 孙巍伟 《组合机床与自动化加工技术》 北大核心 2026年第1期32-40,46,共10页
随着精密加工技术的发展,数控刀具的健康状态对生产质量与效率具有重要影响。针对多模态时间序列数据的融合与多层次时间序列建模挑战,提出了多模态交叉注意力时序融合网络(MCTF-Net)。模型首先通过TCN模块分别捕获每个模态信号的局部... 随着精密加工技术的发展,数控刀具的健康状态对生产质量与效率具有重要影响。针对多模态时间序列数据的融合与多层次时间序列建模挑战,提出了多模态交叉注意力时序融合网络(MCTF-Net)。模型首先通过TCN模块分别捕获每个模态信号的局部时间特征,并通过Transformer的编码器获取全局特征,随后在中期融合层引入跨模态交叉注意力机制,以振动信号为查询融合声发射和电流特征得到统一表示,接着采用TCN-Transformer双路架构同时捕捉局部磨损瞬态模式和建模负载波动的长程依赖,提升异常检测的准确性与鲁棒性。基于PHM2010刀具数据集和自采数据的实验表明,该模型在准确率、F1分数及ROC分数等指标上均优于主流方法。消融实验进一步验证了TCN与Transformer模块的协同作用,为复杂制造环境下的刀具异常检测提供了一种高效、精准的解决方案。 展开更多
关键词 刀具异常检测 多模态数据 时间卷积网络 TRANSFORMER 精密加工
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刀路轨迹中微线段区域分段光顺算法研究
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作者 黄文桂 唐清春 +2 位作者 黄玉坤 刘新宇 杨鸿昆 《煤矿机械》 2026年第1期54-58,共5页
为了解决线性刀具运动轨迹导致的机床加工速度波动和加工质量差等问题,提出了一种新的区域分段光顺算法。首先,根据反曲点、曲率极值点和弓高特征点对离散数据点进行预处理;其次,对预处理的数据进行区域分段光顺算法的判断,选择合适的... 为了解决线性刀具运动轨迹导致的机床加工速度波动和加工质量差等问题,提出了一种新的区域分段光顺算法。首先,根据反曲点、曲率极值点和弓高特征点对离散数据点进行预处理;其次,对预处理的数据进行区域分段光顺算法的判断,选择合适的光顺算法;最后,以蝴蝶形试件为例,对该算法与传统单一光顺算法进行MATLAB仿真分析和实际加工验证。仿真结果表明,该算法通过对数据点的预处理减少96.30%的微小线段,通过选择合适的光顺算法减少了43.27%的控制点个数和48.71%的迭代次数。实际加工验证了该算法的正确性和可行性。 展开更多
关键词 离散数据点 数据预处理 蝴蝶形试件 刀路轨迹
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基于双位置闭环反馈的数控机床进给系统反向间隙测量方法的研究
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作者 都学飞 戴玉红 +5 位作者 徐彪 许强 关方亮 边亚超 康子琳 陈欣 《制造技术与机床》 北大核心 2026年第1期208-214,共7页
针对双位置闭环反馈的数控机床进给系统,其传动精度中的反向间隙直接影响工件的加工精度、质量等,利用机床自身配置的闭环光栅尺系统,开发了一种高效、高精度和可在线实施的进给系统反向间隙检测方法。实验结果表明,该方法的反向间隙检... 针对双位置闭环反馈的数控机床进给系统,其传动精度中的反向间隙直接影响工件的加工精度、质量等,利用机床自身配置的闭环光栅尺系统,开发了一种高效、高精度和可在线实施的进给系统反向间隙检测方法。实验结果表明,该方法的反向间隙检测结果与激光测试数据的最大偏差在0.2μm以内,并且通过运行短时测试程序就可以实现,同时该研究为数控机床动态精度补偿、丝杠健康状态评估提供了理论依据与技术支撑。 展开更多
关键词 反向间隙 光栅尺 闭环控制 数据采集 数控机床 丝杠
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Teradata数据仓库的ETL在电信行业中的设计与实施 被引量:2
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作者 张琴和 李民 《机械设计与制造工程》 2012年第A07期10-13,17,共5页
介绍了Teradata数据仓库和ETL的相关概念,结合电信行业中对数据仓库的ETL流程的要求和特点,对Teradata数据仓库的ETL工具进行模型设计与研究,设计了一套普遍适合电信行业数据仓库的ETL框架模型,并对该模型进行实施,实施结果证明该模型... 介绍了Teradata数据仓库和ETL的相关概念,结合电信行业中对数据仓库的ETL流程的要求和特点,对Teradata数据仓库的ETL工具进行模型设计与研究,设计了一套普遍适合电信行业数据仓库的ETL框架模型,并对该模型进行实施,实施结果证明该模型可行。 展开更多
关键词 数据仓库 TERAdata ETL ETL工具
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Digital Forensics and Cyber Crime Datamining 被引量:2
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作者 K. K. Sindhu B. B. Meshram 《Journal of Information Security》 2012年第3期196-201,共6页
Digital forensics is the science of identifying, extracting, analyzing and presenting the digital evidence that has been stored in the digital devices. Various digital tools and techniques are being used to achieve th... Digital forensics is the science of identifying, extracting, analyzing and presenting the digital evidence that has been stored in the digital devices. Various digital tools and techniques are being used to achieve this. Our paper explains forensic analysis steps in the storage media, hidden data analysis in the file system, network forensic methods and cyber crime data mining. This paper proposes a new tool which is the combination of digital forensic investigation and crime data mining. The proposed system is designed for finding motive, pattern of cyber attacks and counts of attacks types happened during a period. Hence the proposed tool enables the system administrators to minimize the system vulnerability. 展开更多
关键词 CYBER Forensic DIGITAL Forensic tool Network Forensic tool CRIME data MINING
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刀具标识中Data Matrix的编码和解码技术研究 被引量:4
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作者 席卫东 何卫平 +1 位作者 雷蕾 张维 《计算机工程与设计》 CSCD 北大核心 2008年第15期4013-4016,共4页
为了提高数控车间刀具库存管理和生产过程追踪中信息采集的准确性和实时性,提出了一种刀具信息自动采集方案并加以实现。基于Data Matrix编码原理将刀具信息转换成机读二维码,使用激光标刻技术在刀具表面实现该二维码的直接标刻,然后对... 为了提高数控车间刀具库存管理和生产过程追踪中信息采集的准确性和实时性,提出了一种刀具信息自动采集方案并加以实现。基于Data Matrix编码原理将刀具信息转换成机读二维码,使用激光标刻技术在刀具表面实现该二维码的直接标刻,然后对其进行扫描并对图像进行倾斜校正,最后通过Reed-Solomon算法对识读结果进行纠错,实现了刀具信息自动采集的准确性和实时性。 展开更多
关键词 数据矩阵码 激光标刻 里德-索罗门码 刀具信息采集 刀具追踪
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A Middleware for Polyglot Persistence and Data Portability of Big Data PaaS Cloud Applications
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作者 Kiranbir Kaur Sandeep Sharma Karanjeet Singh Kahlon 《Computers, Materials & Continua》 SCIE EI 2020年第11期1625-1647,共23页
Vendor lock-in can occur at any layer of the cloud stack-Infrastructure,Platform,and Software-as-a-service.This paper covers the vendor lock-in issue at Platform as a Service(PaaS)level where applications can be creat... Vendor lock-in can occur at any layer of the cloud stack-Infrastructure,Platform,and Software-as-a-service.This paper covers the vendor lock-in issue at Platform as a Service(PaaS)level where applications can be created,deployed,and managed without worrying about the underlying infrastructure.These applications and their persisted data on one PaaS provider are not easy to port to another provider.To overcome this issue,we propose a middleware to abstract and make the database services as cloud-agnostic.The middleware supports several SQL and NoSQL data stores that can be hosted and ported among disparate PaaS providers.It facilitates the developers with data portability and data migration among relational and NoSQL-based cloud databases.NoSQL databases are fundamental to endure Big Data applications as they support the handling of an enormous volume of highly variable data while assuring fault tolerance,availability,and scalability.The implementation of the middleware depicts that using it alleviates the efforts of rewriting the application code while changing the backend database system.A working protocol of a migration tool has been developed using this middleware to facilitate the migration of the database(move existing data from a database on one cloud to a new database even on a different cloud).Although the middleware adds some overhead compared to the native code for the cloud services being used,the experimental evaluation on Twitter(a Big Data application)data set,proves this overhead is negligible. 展开更多
关键词 Cloud computing platform as a service MIDDLEWARE polyglot persistence SQL NOSQL data migration tool Twitter data set
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Automatic Data Extraction from Websites for Generating Aquatic Product Market Information
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作者 袁红春 陈莹 孙越夫 《Journal of Donghua University(English Edition)》 EI CAS 2006年第6期15-19,共5页
The massive web-based information resources have led to an increasing demand for effective automatic retrieval of target information for web applications. This paper introduces a web-based data extraction tool that de... The massive web-based information resources have led to an increasing demand for effective automatic retrieval of target information for web applications. This paper introduces a web-based data extraction tool that deploys various algorithms to locate, extract and filter tabular data from HTML pages and to transform them into new web-based representations. The tool has been applied in an aquaculture web application platform for extracting and generating aquatic product market information. Results prove that this tool is very effective in extracting the required data from web pages. 展开更多
关键词 web data table localization algorithm distance algorithm data filtering algorithm data extraction tool.
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