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排序方式: 共有192条查询结果,搜索用时 15 毫秒
41.
After the end of data taking in 2007,the experiments H1 and ZEUS have entered into an intense phase of data analysis.Recent results of this effort on neutral (NC) and charged current (CC) cross sections at high Q 2,the longitudinal structure function F L,inclusive diffraction,heavy flavour production and on searches for glueballs are presented.Also shown are results of a combined analysis on inclusive NC and CC cross sections performed by H1 and ZEUS using HERA-I data. 相似文献
42.
该文融合遍历论、粗粒化方法和信息论的观点研究数据流的非平稳性度量问题. 引入了数据流的非平稳性度量的概念, 给出了数据流非平稳性度量的有效的近似算法. 数据流的非平稳性度量为该文融合遍历论、粗粒化方法和信息论的观点研究数据流的非平稳性度量问题. 引入了数据流的非平稳性度量的概念, 给出了数据流非平稳性度量的有效的近似算法. 数据流的非平稳性度量为该文融合遍历论、粗粒化方法和信息论的观点研究数据流的非平稳性度量问题. 引入了数据流的非平稳性度量的概念, 给出了数据流非平稳性度量的有效的近似算法. 数据流的非平稳性度量为$0$和$1$之间的实数,平稳性较好的数据流的非平稳性度量较小. 作者将数据流的非平稳性度量应用到模型选择问题中,提出残差序列非平稳性度量最小化的模型选择标准. 作者用数值试验检验了该文提出的数据流非平稳性度量的近似算法, 并检验了其作为模型选择标准的能力.数值试验的结果表明, 非平稳性度量是衡量数据流非平稳程度的一个合理指标, 可以很好地区分趋势平稳数据和差分平稳数据, 区分独立同分布序列、白噪声序列和鞅差序列. 相似文献
43.
44.
We discuss the analysis of data from πN elastic scattering and single pion photo- and electroproduction. The main focus is a study of low-lying non-strange baryon resonances. Here we concentrate on some difficulties associated with resonance identification, in particular the Roper and higher P11 states. 相似文献
45.
We assess the color appearance of the samples with different inks on glossy substrates, five kinds of paper with different gloss levels. The color samples are measured using spectrophotometers under different illuminating/viewing geometries and visually estimated using the psychophysical method of magnitude estimation. The results of the two approaches are compared through the color appearance model of CIECAM02. The experimental data analysis indicates that the 0/45 and 15/0 geometries can be used to describe the two major aspects of gloss effect, the enlargement of color gamut, and the reduction of lightness. The agreement for hue attribute between instrumental measurement and visual assessment is better than those for colorfulness and lightness. 相似文献
46.
There are highly intensive and stable line-spectrums in the radiated noise of passive target,and different targets have line-spectrums with different frequencies.This paper puts forward Conventional BeamForming(CBF) variance-of-frequency detector,which weights bearing spectrum using the variance of frequency of line spectrum with maximum amplitude in each azimuth. It is able to suppress multi-target interferences effectively,and detect faint signal in the background of strong interferences.What’s more,CBF variance-of-frequency detector needs only three-dimension display,while other line-spectrum detectors require for four-dimension display.The simulation and trial data analysis show that the CBF variance-of-frequency detector is able to detect faint line-spectrum target in the background of the continuous spectrum strong interferences. 相似文献
47.
In the LHC experiment, the neutral pions produced during jet fragmentation are the background sources for all physics channels with high-energy photons in their final state. In this paper, the application of the three-dimensional parametric formula for electromagnetic (EM) showers, which we developed in the Alpha Magnetic Spectrometer II experiment, is presented to distinguish the unconverted photons from the neutral pions. With the constructed electromagnetic calorimeter (ECAL) in a GEANT4 simulation, the parametric formulae were validated and the unconverted γπ0 discrimination was performed with the Toolkit for Multivariate Data Analysis (TMVA) package in ROOT for different transverse energies ranging from 15 GeV to 75 GeV, which is the most sensitive region for light Higgs (with mass ~120 GeV) searches with the channel H→γγ. With this discrimination method and the selected transverse energy region, we can reject π0 with the efficiency from ~40% (65--75 GeV) to ~90% (15--25 GeV) when keeping 90% γ efficiency. 相似文献
48.
The fast turnover of software technologies,in particular in the domain of in teractivity(covering user interface and visualisation)makes it difficult for a small group of people to produce complete and polished software-tools before the underlying technologies make them obsolete.At the HepVis ‘99 workshop,a working group has been formed to improve the rpoduction of software tools for data analysis in HENP.Beside promoting a distributed development organisation,one goal of the group is to systematically design a set of abstract interfaces based on using modern OO analysis and OO design techniques.An initial domain analysis has come up with several categories(componets)found in typical data analysis tools:historams,Ntuples,Functions,Vectors,Fitter,Plotter,Analyzer and Controller,Special Emphasis was put on reducing the couplings between the categories to a minimum,thus optimising re-use and maintainability of any component individually.The interfaces have been defined in Java and C and implementations exist in the form of libraries and tools using C (Anaphe/Lizard,Openscientist)and Java(Java Analysis Studio),A special implementation aims at accessing the Java Liraries(through their Abstract Interfaces)from C .This paper giver an overview of the architecture and design of the various components for data analysis as discussed in AIDA. 相似文献
49.
博客(Blog)网站作为近年来新型的网络媒体得到越来越多的个人和企业的关注,因此针对Blog数据设计了相应的数据分析系统.并介绍了Blog数据分析与传统Web挖掘的区别和联系,阐明研究了Blog数据的必要性,其次详细分析了本系统的主要功能模块及其实现方法,最后采集中国博客网的数据对本系统进行验证,实验结果显示本系统是可行且有效的. 相似文献
50.