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1.
针对数据量较小时,克里金插值精度低的问题,将克里金插值模型与半监督学习理论相结合,利用未标记样本参与训练改进模型性能,提出基于半监督学习的克里金插值模型,即自训练克里金插值模型(STK)和协同训练克里金插值模型(CTK)。以北京地区2017年4月和5月的PM2.5浓度数据作为实验数据,采用克里金插值模型、STK和CTK进行对比实验。实验结果表明,这两个模型既具有半监督学习的优点,适用于只有少量标记样本的情况,又可以分析空间现象的分布模式。其中CTK采用两个模型协同训练,有效削弱了早期误差对后期训练的影响,利用未标记样本提升了模型的性能。  相似文献   

2.
在室内位置指纹定位技术中,采用克里金插值算法可有效降低指纹数据库构建的工作量, 但是,现有算法通常只考虑了信号在一维方向上的变异性,没有考虑室内环境中信号在多个方向存在的变异性。为此,本文提出了一种融合了多个方向信号变异性的改进克里金插值算法,充分考虑了二维室内环境中信号在不同方向的变异性对插值精度的影响。实验结果表明,与克里金插值算法、距离反比加权插值算法等算法相比,本文算法对指纹数据的插值精度更高。  相似文献   

3.
加权最小二乘法改进遗传克里金插值方法研究   总被引:3,自引:0,他引:3  
数据内插被广泛应用于地统计分析领域,克里金插值作为其中最为有效的方法之一,其原理是通过建立变异函数理论模型,得到可靠的权重值和拉格朗日系数,构成求解待测点的线性组合。为了有效地提高插值精度,文中利用加权最小二乘法优化遗传算法中的适应度函数,进而改进普通基于遗传算法优化的克里金插值方法。并且在MATLAB中利用外部工具箱确定模型参数,最后通过实例验证,将该方法与普通克里金插值以及遗传克里金插值结果进行对比,发现采用该方法,插值效果较好且误差也较小,证明了通过加权最小二乘法可以有效改进普通遗传克里金插值方法。  相似文献   

4.
针对积雪观测站点稀少的问题,提出一种考虑海拔影响,能够融合MODIS积雪面积产品和站点观测的雪深空间插值方法,该方法利用去云后MODIS积雪面积产品构建的无积雪“虚拟站点”弥补站点分布不均匀和稀少的不足,利用泛协克里金插值方法考虑海拔对雪深的影响。利用北疆地区50个气象站点的逐日雪深观测资料、逐日MODIS积雪面积产品和AMSR-E被动微波雪水当量和雪深产品,对普通克里金、泛克里金、普通协克里金和泛协克里金插值结果进行了比较研究。研究结果表明:积雪覆盖范围较大时,站点雪深与海拔之间相关系数较大,利用泛协克里金插值结果精度高且稳定;否则利用普通克里金插值精度较高且稳定。通过增加“虚拟站点”,能够提高雪深插值精度,并在一定程度上修正了克里金插值中存在的平滑效应。
  相似文献   

5.
空间插值分析算法综述   总被引:3,自引:0,他引:3  
空间插值分析算法是一种应用于将离散点的测量数据转换为连续数据表面的算法,能够将连续数据曲面与其他空间现象的分布情况进行比较,它在空间信息方面具有广泛的应用场景,尤其是地理信息方面.对泰森多边形法、反距离权重插值法、样条函数插值法、克里金插值法等空间插值算法的插值原理和应用场景进行综述,对空间插值分析算法的进展和未来研究方向进行了探讨.  相似文献   

6.
本文根据"北海区环境预报信息集成系统"对于ArcGis Engine中常用空间插值算法进行研究,主要研究了反距离加权插值算法、克里金插值算法、样条函数插值算法,并对反距离加权插值算法进行了改进,在本系统中利用该算法进行插值计算。研究各个算法的实现原理及各个算法的有缺点。经研究发现:应用Kriging插值算法的插值效果较好,IDW插值算法简单、易于实现,Spline算法计算量小,可以产生平滑的曲线。  相似文献   

7.
人工神经网络在降水量空间插值中的应用研究   总被引:1,自引:0,他引:1  
降水的空间分布信息在水资源管理与分析中越来越重要,而降水插值是获取降水量信息的重要途径.对云南省内117个站点进行月平均、年平均的空间降水插值试验,采用融合地理信息的BP网络模型和径向基函数网络模型,并选取反距离加权法和克里金方法,对各种方法的插值结果进行对比分析,计算结果表明,人工神经网络方法可调参数较少,操作简单,插值效果较好.  相似文献   

8.
三维地震属性数据巨大,在实际应用中一般采用局域克里金插值算法进行插值。目前常用的指定距离半径、指定点数、kd-tree等搜索算法均涉及距离计算、遍历已知点,相对较为费时。对此,提出一种无须距离计算、无须遍历已知点而直接利用待插值点位置的增减实现邻域点的选取方法(VAOS),以高效实现克里金插值。经过实验验证,在同精度下,该算法比距离半径搜索法快数十倍。  相似文献   

9.
空间克里金插值的时空扩展与实现   总被引:4,自引:0,他引:4  
徐爱萍  胡力  舒红 《计算机应用》2011,31(1):273-276
空间克里金插值常用来补充采样点不足的问题,当数据分布与时间和空间都有关系时,面向空间的方法直接应用到时空过程可能导致有价值信息在时间维的丢失,由此导致了时空克里金插值的研究。研究的目标是将空间插值模型扩展到时空领域并实现时空变异函数、时空插值和时空交叉验证。其方法是首先获得最佳变异函数模型和时空下的有效基台值、块金值与变程,然后实现时空克里金插值的扩展,最后通过时空交叉验证去验证扩展的时空克里金插值方法的有效性。验证结果表明,扩展的时空方法能为随机领域以一定的精度提供较多的信息,为不同时空环境下的预测或插值提供了一个有效的途径。  相似文献   

10.
当采样点数据量较大时, 可以采用Delaunay三角剖分建立三角网来使用局部邻域采样点进行克里金插值. 但是该算法需要对每个插值点拟合半变异函数, 插值点规模大时造成巨大开销. 为此, 本文提出了一种以三角形为单位拟合半变异函数的克里金插值方法, 采用CPU-GPU负载均衡将部分计算优化, 充分考虑不均匀样本对克里金插值效果的影响. 结果表明, 本文算法能够保证不均匀样本集的插值效果, 提升了计算性能且能够保证较高的精度.  相似文献   

11.
Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.  相似文献   

12.
European Community policy and the market   总被引:1,自引:0,他引:1  
Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.  相似文献   

13.
融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。  相似文献   

14.
Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.  相似文献   

15.
This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.  相似文献   

16.
Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   

17.
为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.  相似文献   

18.
Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.  相似文献   

19.
This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)SM and Team Software Process (TSP){SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.  相似文献   

20.
基于复小波噪声方差显著修正的SAR图像去噪   总被引:4,自引:1,他引:3  
提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。  相似文献   

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