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For the typical color detects of polysilicon wafers, i.e., edge discoloration, color inaccuracy and color non-uniformity, a new integrated machine vision detection method is proposed based on an HSV color model. By transforming RGB image into three-channel HSV images, the HSV model can efficiently reduce the disturbances of complex wafer textures. A fuzzy color clustering method is used to detect edge discoloration by defining membership function for each channel image. The mean-value classi- fying method and region growing method are used to identify the other two defects, respectively. A vision detection system is developed and applied in the produc- tion of polysilicon wafers. 相似文献
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我国的图书馆事业在“文化大革命”中遭受了空前的浩劫和摧残。以1971年为界,可将文革中的图书馆事业划分为两个时期。文革前期图书馆事业遭到严重破坏,文革后期图书馆事业艰难恢复。文革中编制了《中国图书馆图书分类法》,启动了《汉语主题词表》编制工作,引入了机读目录。 相似文献
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Review helpfulness is attracting increasing attention of practitioners and academics. It helps in reducing risks and uncertainty faced by users in online shopping. This study examines uninvestigated variables by looking at not only the review characteristics but also important indicators of reviewers. Several significant review content and two reviewer variables are proposed and an effective review helpfulness prediction model is built using stochastic gradient boosting learning method. This study derived a mechanism to extract novel review content variables from review text. Six popular machine learning models and three real-life Amazon review data sets are used for analysis. Our results are robust to several product categories and along three Amazon review data sets. The results show that review content variables deliver the best performance as compared to the reviewer and state-of-the-art baseline as a standalone model. This study finds that reviewer helpfulness per day and syllables in review text strongly relates to review helpfulness. Moreover, the number of space, aux verb, drives words in review text and productivity score of a reviewer are also effective predictors of review helpfulness. The findings will help customers to write better reviews, help retailers to manage their websites intelligently and aid customers in their product purchasing decisions. 相似文献
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Most work in the design of learning technology uses click-streams as their primary data source for modelling & predicting learning behaviour. In this paper we set out to quantify what, if any, advantages do physiological sensing techniques provide for the design of learning technologies. We conducted a lab study with 251 game sessions and 17 users focusing on skill development (i.e., user's ability to master complex tasks). We collected click-stream data, as well as eye-tracking, electroencephalography (EEG), video, and wristband data during the experiment. Our analysis shows that traditional click-stream models achieve 39% error rate in predicting learning performance (and 18% when we perform feature selection), while for fused multimodal the error drops up to 6%. Our work highlights the limitations of standalone click-stream models, and quantifies the expected benefits of using a variety of multimodal data coming from physiological sensing. Our findings help shape the future of learning technology research by pointing out the substantial benefits of physiological sensing. 相似文献
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张宏伟 《铜仁职业技术学院学报》2006,(2)
本文从电源、接地、机房三个方面,阐述了我区基层医院在安装X线机时存在的问题,以引起有关部门领导的重视,并提出了解决这些问题的建议。 相似文献
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刘玉敏 《现代图书情报技术》2003,(Z1)
文章结合互联网的特点 ,从几个方面较详细地介绍了专业信息的网上检索方法 ,并就检索过程中可能会遇到的难点提供了一些具体的技术解决措施。然后 ,针对目前互联网信息检索的实际使用状况 ,作者指出了几个有待改进的不足之处 ,并提出了一些具体的解决办法 相似文献
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闫佳 《孝感职业技术学院学报》2008,11(2):93-96
文章以某粮食港口为例,根据该项目的实际情况,介绍了该粮食港口的工艺流程并应用组态软件RSViewSE对该港口粮流系统操作员站进行了设计。人机界面简洁友好,操作使用方便,体现了RSView SE在实际应用中的灵活性以及卓越特性。 相似文献
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INTRODUCTION Fuel cells have attracted more attention in the last few years due to scarcity of the world energy source. The Proton Exchange Membrane Fuel Cell (PEMFC) is the focus of current development efforts because it is capable of higher power density and faster start-up than other fuel cells (Zhang et al., 2004). Research emphasis is on high power density with adequate energy conversion efficiency. PEMFC performance is related to many factors, among which electrolyte membrane … 相似文献