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固汞与液汞对荧光灯企业汞作业工人健康影响的比较 被引量:7
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作者 吴京颖 许旭艳 江碧云 《海峡预防医学杂志》 CAS 2008年第4期91-92,共2页
[目的]比较固汞与液汞对荧光灯企业汞作业工人健康的影响。[方法]按《职业健康检查项目及周期》规定对汞作业工人进行职业健康检查。尿汞用原子荧光光谱法测定,生产环境监测按GBZ159-2004和GBZ/T160.14-2004规定进行。[结果]固汞作业场... [目的]比较固汞与液汞对荧光灯企业汞作业工人健康的影响。[方法]按《职业健康检查项目及周期》规定对汞作业工人进行职业健康检查。尿汞用原子荧光光谱法测定,生产环境监测按GBZ159-2004和GBZ/T160.14-2004规定进行。[结果]固汞作业场所汞浓度为0.0082±0.005mg/m3;液汞作业场所汞浓度为0.0260±0.008mg/m3,液汞高于固汞;类神经征检出率液汞组(32.9%)高于固汞组(12.3%),P<0.01;尿汞定量固汞组为0.0035±0.003mg/L,液汞组为0.0112±0.007mg/L,液汞组高于固汞组。[结论]固汞对荧光灯企业作业场所的污染及对作业工人健康的危害比液汞小,在目前荧光灯企业汞尚无替代品情况下,推广固汞的使用具有十分重要的现实意义。 展开更多
关键词 职业卫生 荧光灯企业 尿汞 类神经征
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EFFECTIVE FEATURE ANALYSIS FOR COLOR IMAGE SEGMENTATION 被引量:2
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作者 黎宁 毛四新 李有福 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2001年第2期206-212,共7页
An approach for color image segmentation is proposed based on the contributions of color features to segmentation rather than the choice of a particular color space. The determination of effective color features depen... An approach for color image segmentation is proposed based on the contributions of color features to segmentation rather than the choice of a particular color space. The determination of effective color features depends on the analysis of various color features from each tested color image via the designed feature encoding. It is different from the pervious methods where self organized feature map (SOFM) is used for constructing the feature encoding so that the feature encoding can self organize the effective features for different color images. Fuzzy clustering is applied for the final segmentation when the well suited color features and the initial parameter are available. The proposed method has been applied in segmenting different types of color images and the experimental results show that it outperforms the classical clustering method. The study shows that the feature encoding approach offers great promise in automating and optimizing the segmentation of color images. 展开更多
关键词 image segmentation color image neural networks fuzzy clustering feature encoding
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An Automated Approach to Passive Sonar Classification Using Binary Image Features
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作者 Vahid Vahidpour Amlr Rastegarnia Azam Khalili 《Journal of Marine Science and Application》 CSCD 2015年第3期327-333,共7页
This paper proposes a new method for ship recognition and classification using sound produced and radiated underwater. To do so, a three-step procedure is proposed. First, the preprocessing operations are utilized to ... This paper proposes a new method for ship recognition and classification using sound produced and radiated underwater. To do so, a three-step procedure is proposed. First, the preprocessing operations are utilized to reduce noise effects and provide signal for feature extraction. Second, a binary image, made from frequency spectrum of signal segmentation, is formed to extract effective features. Third, a neural classifier is designed to classify the signals. Two approaches, the proposed method and the fractal-based method are compared and tested on real data. The comparative results indicated better recognition ability and more robust performance of the proposed method than the fractal-based method. Therefore, the proposed method could improve the recognition accuracy of underwater acoustic targets. 展开更多
关键词 binary image passive sonar neural classifier ship recognition short-time Fourier transform fractal-based method
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低血铅暴露与神经系统症状的关系 被引量:6
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作者 窦倩如 王艳 +2 位作者 蔡畅 李继猛 谭红专 《中华流行病学杂志》 CAS CSCD 北大核心 2015年第5期515-518,共4页
目的探讨油漆工人的低血铅暴露与神经系统症状之间的关系。方法采用整群抽样的方法,抽取2个油漆相关企业的所有接触油漆的工人为样本,对其进行问卷调查、生化检测及体格检查。采用单因素)c2检验和多因素非条件logistic回归分析的方... 目的探讨油漆工人的低血铅暴露与神经系统症状之间的关系。方法采用整群抽样的方法,抽取2个油漆相关企业的所有接触油漆的工人为样本,对其进行问卷调查、生化检测及体格检查。采用单因素)c2检验和多因素非条件logistic回归分析的方法探讨低血铅和其他因素暴露对神经系统症状的影响。结果收集到完整资料的有525例,其中血铅阳性者55例(10.5%);血铅阳性者的血铅均值为(0.0884±O.0539)mg/L;278例(52.95%)出现类神经征;69例(13.14%)出现周围神经病症状。多因素非条件logistic回归分析显示:工龄(OR=1.827)、饮酒(OR=1.607)、健康状况(OR=3.862)、血铅(OR=1.983)与类神经征有关。工龄(OR=2.282)、饮酒(OR=2.704)与周围神经病有关。结论低浓度血铅暴露可能与类神经征的发生相关。 展开更多
关键词 血铅 类神经征 周围神经
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Two-level hierarchical feature learning for image classification 被引量:3
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作者 Guang-hui SONG Xiao-gang JIN +1 位作者 Gen-lang CHEN Yan NIE 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2016年第9期897-906,共10页
In some image classification tasks, similarities among different categories are different and the samples are usually misclassified as highly similar categories. To distinguish highly similar categories, more specific... In some image classification tasks, similarities among different categories are different and the samples are usually misclassified as highly similar categories. To distinguish highly similar categories, more specific features are required so that the classifier can improve the classification performance. In this paper, we propose a novel two-level hierarchical feature learning framework based on the deep convolutional neural network(CNN), which is simple and effective. First, the deep feature extractors of different levels are trained using the transfer learning method that fine-tunes the pre-trained deep CNN model toward the new target dataset. Second, the general feature extracted from all the categories and the specific feature extracted from highly similar categories are fused into a feature vector. Then the final feature representation is fed into a linear classifier. Finally, experiments using the Caltech-256, Oxford Flower-102, and Tasmania Coral Point Count(CPC) datasets demonstrate that the expression ability of the deep features resulting from two-level hierarchical feature learning is powerful. Our proposed method effectively increases the classification accuracy in comparison with flat multiple classification methods. 展开更多
关键词 Transfer learning Feature learning Deep convolutional neural network Hierarchical classification Spectral clustering
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