期刊文献+
共找到5篇文章
< 1 >
每页显示 20 50 100
On Accurate Detection of Oceanic Features from Satellite IR Data Using ICSED Method
1
作者 李俊 周风仙 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1992年第3期373-382,共10页
ICSED (Improved Cluster Shade Edge Detection) algorithm and other various methods to accurately and efficiently detect edges on satellite data are presented. Error rate criterion is used to statistically evaluate the ... ICSED (Improved Cluster Shade Edge Detection) algorithm and other various methods to accurately and efficiently detect edges on satellite data are presented. Error rate criterion is used to statistically evaluate the performances of these methods in detecting oceanic features for both noise free and noise contaminated AVHRR (Advanced Very High Resolution Radiometer) IR image with Kuroshio. Also, practical experiments in detecting the eddy of Kuroshio with these methods are carried out for comparison. Results show that the ICSED algorithm has more advantages than other methods in detecting mesoscale features of ocean. Finally, the effectiveness of window size of ICSED method to oceanic features detection is quantitatively discussed. 展开更多
关键词 On Accurate Detection of Oceanic features from Satellite IR data Using ICSED Method IR
下载PDF
A Comparative Study on Two Techniques of Reducing the Dimension of Text Feature Space
2
作者 Yin Zhonghang, Wang Yongcheng, Cai Wei & Diao Qian School of Electronic & Information Technology, Shanghai Jiaotong University, Shanghai 200030, P.R.China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2002年第1期87-92,共6页
With the development of large scale text processing, the dimension of text feature space has become larger and larger, which has added a lot of difficulties to natural language processing. How to reduce the dimension... With the development of large scale text processing, the dimension of text feature space has become larger and larger, which has added a lot of difficulties to natural language processing. How to reduce the dimension has become a practical problem in the field. Here we present two clustering methods, i.e. concept association and concept abstract, to achieve the goal. The first refers to the keyword clustering based on the co occurrence of 展开更多
关键词 in the same text and the second refers to that in the same category. Then we compare the difference between them. Our experiment results show that they are efficient to reduce the dimension of text feature space. Keywords: Text data mining
下载PDF
Feature Extraction of Time Series Data Based on CNN-CBAM
3
作者 Jiaji Qin Dapeng Lang Chao Gao 《国际计算机前沿大会会议论文集》 EI 2023年第1期233-245,共13页
Methods for extracting features from time series data using deep learning have been widely studied,but they still suffer from problems of severe loss of feature information across different network layers and paramete... Methods for extracting features from time series data using deep learning have been widely studied,but they still suffer from problems of severe loss of feature information across different network layers and parameter redun-dancy.Therefore,a new time-series data feature extraction model(CNN-CBAM)that integrates convolutional neural networks(CNN)and convolutional attention mechanisms(CBAM)is proposed.First,the parameters of the CNN and BiGRU prediction models are optimized through uniform design methods.Next,the CNN is used to extract features from the time series data,outputting multiple feature maps.These feature maps are then subjected to feature re-extraction by the CBAM attention mechanism at both the spatial and channel levels.Finally,the feature maps are input into the BiGRU model for prediction.Experimental results show that after CNN-CBAM processing,the stability and accuracy of the BiGRU pre-diction model improved by 77.6%and 76.3%,respectively,outperforming other feature extraction methods.Meanwhile,the training time of the model has only increased by 7.1%,demonstrating excellent time efficiency. 展开更多
关键词 Uniform Design CNN CBAM Time-series data feature Extraction
原文传递
Analyzing Electricity Consumption via Data Mining 被引量:1
4
作者 LIU Jinshuo LAN Huiying +2 位作者 FU Yizhen WU Hui LI Peng 《Wuhan University Journal of Natural Sciences》 CAS 2012年第2期121-125,共5页
This paper proposes a model to analyze the massive data of electricity.Feature subset is determined by the correla-tion-based feature selection and the data-driven methods.The attribute season can be classified succes... This paper proposes a model to analyze the massive data of electricity.Feature subset is determined by the correla-tion-based feature selection and the data-driven methods.The attribute season can be classified successfully through five classi-fiers using the selected feature subset,and the best model can be determined further.The effects on analyzing electricity consump-tion of the other three attributes,including months,businesses,and meters,can be estimated using the chosen model.The data used for the project is provided by Beijing Power Supply Bureau.We use WEKA as the machine learning tool.The models we built are promising for electricity scheduling and power theft detection. 展开更多
关键词 feature selection multi-classification prediction model data analysis
原文传递
Similarity Search Algorithm over Data Supply Chain Based on Key Points 被引量:1
5
作者 Peng Li Hong Luo Yan Sun 《Tsinghua Science and Technology》 SCIE EI CAS CSCD 2017年第2期174-184,共11页
In this paper, we target a similarity search among data supply chains, which plays an essential role in optimizing the supply chain and extending its value. This problem is very challenging for application-oriented da... In this paper, we target a similarity search among data supply chains, which plays an essential role in optimizing the supply chain and extending its value. This problem is very challenging for application-oriented data supply chains because the high complexity of the data supply chain makes the computation of similarity extremely complex and inefficient. In this paper, we propose a feature space representation model based on key points,which can extract the key features from the subsequences of the original data supply chain and simplify it into a feature vector form. Then, we formulate the similarity computation of the subsequences based on the multiscale features. Further, we propose an improved hierarchical clustering algorithm for a similarity search over the data supply chains. The main idea is to separate the subsequences into disjoint groups such that each group meets one specific clustering criteria; thus, the cluster containing the query object is the similarity search result. The experimental results show that the proposed approach is both effective and efficient for data supply chain retrieval. 展开更多
关键词 data supply chain similarity search feature space hierarchical clustering
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部