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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
YU Cheng-Jian 《数字社区&智能家居》2008,(12)
在Web页面常用到表格这种元素。本文提出一种根据表格语义来进行信息抽取方法。首先提出了一种短语语义相似度的度量方法,然后利用短语语义的相似度确定表格标题行(列),并对表格行(列)与抽取字段的对应关系进行计算,最后计算表格的整体语义,度量该表格与所要抽取的内容有多大相关度。 相似文献
992.
In the blind source extraction problem, the concept of generalized autocorrelations has been successfully used when the desired
signal has special temporal structures. However, their applications are only limited to noise-free mixtures, which is not
realistic. Therefore, this paper addresses the extraction of the noisy model based on these temporal characteristics of sources.
An objective function, which combines Gaussian moments and generalized autocorrelations, is proposed. Maximizing this objective
function, we present a blind source extraction algorithm for noisy mixtures. Simulations on synthesized signals, images, artificial
electrocardiogram (ECG) data and the real-world ECG data show the better performance of the proposed algorithm. Moreover,
comparisons with the existing algorithms further indicate its validity and also show its robustness to the estimated error
of time delay. 相似文献
993.
Xiaodong Gu 《Neural Processing Letters》2008,27(1):25-41
In this paper, we use Unit-linking PCNN (Pulse Coupled Neural Network), the simplified model of PCNN consisting of spiking
neurons, to code a 2-dimensional image into a 1-dimensional time sequence called global Unit-linking PCNN image icon or time
signature, including features of the original image and having the translation, rotation, and scale invariance. Dividing an
image into multiple parts can obtain local Unit-linking PCNN image icons corresponding to the image’s local regions, which
can reflect the local changes of the image. In the meantime, the global and the local Unit-linking PCNN image icons are used
in navigation, object detection, and image authentication. In navigation, global Unit-linking PCNN image icon shows qualified
performance especially in non-stationary-video navigation. Object detection using global Unit-linking PCNN image icon, is
independent of variances of translation, rotation, and scale, and object segmentation is avoided. In image authentication,
using local Unit-linking PCNN image icon can authenticate correctly some juggled images failed to authenticate by using local
histogram or local mean intensity, and can locate the juggled positions in the juggled images with some accuracy. 相似文献
994.
Sherif Abdleazeem Ezzat El-Sherif 《International Journal on Document Analysis and Recognition》2008,11(3):127-141
In this paper, we fill a gap in the literature by studying the problem of Arabic handwritten digit recognition. The performances
of different classification and feature extraction techniques on recognizing Arabic digits are going to be reported to serve
as a benchmark for future work on the problem. The performance of well known classifiers and feature extraction techniques
will be reported in addition to a novel feature extraction technique we present in this paper that gives a high accuracy and
competes with the state-of-the-art techniques. A total of 54 different classifier/features combinations will be evaluated
on Arabic digits in terms of accuracy and classification time. The results are analyzed and the problem of the digit ‘0’ is
identified with a proposed method to solve it. Moreover, we propose a strategy to select and design an optimal two-stage system
out of our study and, hence, we suggest a fast two-stage classification system for Arabic digits which achieves as high accuracy
as the highest classifier/features combination but with much less recognition time. 相似文献
995.
本文提出了一个完整的人脸检测与识别系统。首先利用“参考白”技术进行了光线补偿,然後利用肤色及人脸结构特徵实现了人脸检测,并考虑了类似肤色的影响,最後根据人脸图像的灰度特性和几何特性,采用投影法和人脸五官的比例关系进行定位和提取,并在多媒体数据库中实现了人脸照片的直接查询。 相似文献
996.
This paper describes a new approach of heterogeneous data source fusion. Data sources are either static or active: static data sources can be structured or semi-structured, whereas active sources are services. In order to develop data sources fusion systems in dynamic contexts, we need to study all issues raised by the matching paradigms. This challenging problem becomes crucial with the dominating role of the internet. Classical approaches of data integration, based on schemas mediation, are not suitable to the World Wide Web (WWW) environment where data is frequently modified or deleted. Therefore, we develop a loosely integrated approach that takes into consideration both conflict management and semantic rules which must be enriched in order to integrate new data sources. Moreover, we introduce an XML-based Multi-data source Fusion Language (MFL) that aims to define and retrieve conflicting data from multiple data sources. The system, which is developed according to this approach, is called MDSManager (Multi-Data Source Manager). The benefit of the proposed framework is shown through a real world application based on web data sources fusion which is dedicated to online markets indices tracking. Finally, we give an evaluation of our MFL language. The results show that our language improves significantly the XQuery language especially considering its expressiveness power and its performances. 相似文献
997.
张绍兵 《计算机测量与控制》2008,16(12):1994-1995,2002
针对无指针式仪表表盘的数字识别问题,提出一种基于特征提取和粗糙集特征约简的神经网络数字识别方法;该方法首先利用数字图像预处理技术处理图像并利用特征提取方法提取数字图像特征,然后利用粗糙集理论进行特征约简,最后将约简后的信息输入到训练好的神经网络进行识别;实验表明,相对于传统方法,该方法具有识别率高、速度快的特点,具有较高的实用价值;并且该方法在保留神经网络高鲁棒性的同时,为快速准确地进行数字识别开辟了新的途径。 相似文献
998.
Since the various people involved in the design process for a building project tend to hold conflicting views, this inevitably
leads to a range of disparate models for planning and calculation purposes. In order to interpret the relevant geometrical,
topological and semantical data for any given building model, we identify a structural component graph, a graph of room faces,
a room graph and a relational object graph as aids and explain algorithms to derive these relations. We start with a building
model by transferring its geometrical, topological and semantical data into a volume model, decomposing the latter into a
so-called connection model and then extracting all air volume bodies and hulls of the model by means of further decomposition
into elementary cyclic connection components. The technique is demonstrated within the scope of building energy simulation
by deriving both a dimensionally reduced object model required for setting up a thermal multizone model and a geometrical
model for defining single or multiple computational fluid dynamic domains in a building together with incidence matrices correlating
these models. The algorithm is basically applicable to any building energy simulation tool.
相似文献
Ernst RankEmail: |
999.
Saliency, Scale and Image Description 总被引:6,自引:0,他引:6
1000.
Roman Rosipal Mark Girolami Leonard J. Trejo Andrzej Cichocki 《Neural computing & applications》2001,10(3):231-243
In this paper, we propose the application of the Kernel Principal Component Analysis (PCA) technique for feature selection
in a high-dimensional feature space, where input variables are mapped by a Gaussian kernel. The extracted features are employed
in the regression problems of chaotic Mackey–Glass time-series prediction in a noisy environment and estimating human signal
detection performance from brain event-related potentials elicited by task relevant signals. We compared results obtained
using either Kernel PCA or linear PCA as data preprocessing steps. On the human signal detection task, we report the superiority
of Kernel PCA feature extraction over linear PCA. Similar to linear PCA, we demonstrate de-noising of the original data by
the appropriate selection of various nonlinear principal components. The theoretical relation and experimental comparison
of Kernel Principal Components Regression, Kernel Ridge Regression and ε-insensitive Support Vector Regression is also provided. 相似文献