Using lexical chains for keyword extraction

Keywords can be considered as condensed versions of documents and short forms of their summaries. In this paper, the problem of automatic extraction of keywords from documents is treated as a supervised learning task. A lexical chain holds a set of semantically related words of a text and it can be said that a lexical chain represents the semantic content of a portion of the text. Although lexical chains have been extensively used in text summarization, their usage for keyword extraction problem has not been fully investigated. In this paper, a keyword extraction technique that uses lexical chains is described, and encouraging results are obtained.     

天平灵敏度的影响因素分析与检修

对天平灵敏度的影响因素进行了全面分析，并找出相应的解决办法。     

Digital Signal Processing Based Real Time Vehicular Detection System

Traffic monitoring is of major importance for enforcing traffic management policies. To accomplish this task, the detection of vehicle can be achieved by exploiting image analysis techniques. In this paper, a solution is presented to obtain various traffic parameters through vehicular video detection system( VVDS). VVDS exploits the algorithm based on virtual loops to detect moving vehicle in real time. This algorithm uses the background differencing method, and vehicles can be detected through luminance difference of pixels between background image and current image. Furthermore a novel technology named as spatio-temporal image sequences analysis is applied to background differencing to improve detection accuracy. Then a hardware implementation of a digital signal processing (DSP) based board is described in detail and the board can simultaneously process fourchannel video from different cameras. The benefit of usage of DSP is that images of a roadway can be processed at frame rate due to DSP‘s high performance. In the end, VVDS is tested on realworld scenes and experiment results show that the system is both fast and robust to the surveillance of transportation.     

离心泵特性曲线测定中的Excel 2000的应用

简述了“离心泵特性曲线测定”中实验原理、实验装置和实验方法;重点探讨了 Excel 2000在化学工艺学实验数据处理中的应用。     

铁炭微电解法在单晶硅生产废水处理中的应用

介绍了某单晶硅生产改扩建各工序产生废水的水量、水质，并对原废水处理站存在的问题进行分析。在原废水处理站的基础上，采用生铁屑和焦炭组成微电解氧化还原塔作为单晶硅生产废水处理的预处理，取得较好的效果．     

李商隐诗歌中的“蝉”意象

李商隐笔下的"蝉"与以往诗人所吟咏的"蝉"有很明显的区别,他没有着意抒写"蝉"的清高不食,而是重在阐发"蝉"所蕴含的幽怨惆怅的涵义。李商隐诗歌中的"蝉"之所以会有这样的内涵,主要源于他幽愁敏感的悲剧性格和晚唐颓丧的时代风气。     

The developing mental lexicon: evidence from morphological priming of irregular Hebrew forms

This study investigated the development of automatic word recognition processes, in particular the development of the morphological level of processing. We examined masked priming of Hebrew irregular forms at two levels of reading experience. Both third- and seventh-grade children showed morphological priming for defective roots when primes and targets conformed to the canonical morphological structure, containing all three letters of the roots, and also when the surface form of the primes and targets contained only two of the root letters. However, priming was not observed when primes and targets did not overlap in the surface form of the roots, i.e. the full three-letter root as prime and only two root letters in the target. These results suggest that both tri- and bi-consonantal representations of defective roots exist in the mental lexicon of young readers. The formation of interconnections between these allomorphic representations, however, requires more extensive reading experience.     

广东加工贸易转型升级对策研究

加工贸易一直是广东省对外贸易的重要组成部分和利用外资的重要方式,已经成为广东对外经济贸易持续快速发展的主要推动力。在经济转型的新的发展阶段,研究促进广东加工贸易的转型升级对策,对促使广东省加工贸易向更高技术含量、更大增值环节发展,实现加工贸易持续健康发展均有着深远意义。     

掠夺性科技期刊与科技期刊中掠夺性现象的特征研究

近年来,由于开放存取(OA)出版模式的兴起,掠夺性科技期刊的出现也引起国内外学者的关注。国内科技期刊中也存在着类似的管理和学术信誉差、商业利益至上的现象,并对正常的科研成果和出版资源形成了干扰和掠夺。本文将这些存在于国内外科技期刊中的掠夺现象一并回顾和总结,认为一方面国内科技期刊从业者,应重视和适应新兴OA期刊的发展趋势,另一方面相关科研管理部门也应逐步建立措施,完善掠夺性期刊预警制度。     

中文自动问答中旬子相似度计算研究

句子相似度计算是自动问答系统的重要理论基础和关键实现技术.目前,用于中文自动问答系统的句子相似度计算方法很多,由于缺乏系统的分析,给研究人员带来了较大的不便.依据所利用的特征信息,可以将这些方法分为四类,即基于关键词信息、基于语义信息、基于句法结构信息以及基于多重信息.通过对各类方法实验结果的比较,指出各自的优势和不足.同时指出,基于多重信息的方法是当前的主流方法,实现不同特征信息的最佳权重分配是该类方法今后的研究重点.另外,还提出一个有关相似度概念认识上的看法,即对于中文自动问答系统,实质上依据的是句子的相关度,而不是句子的相似度.通过本文的研究,旨在为中文自动问答领域的句子相似度计算研究提供一定的参考.