• ETRI Journal
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• 제33권1호
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• pp.78-88
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• 2011

In this paper, we present the Touch Text exTractor (Touch TT), an interactive text segmentation tool for the extraction of scene text from camera-based images. Touch TT provides a natural interface for a user to simply indicate the location of text regions with a simple touchline. Touch TT then automatically estimates the text color and roughly locates the text regions. By inferring text characteristics from the estimated text color and text region, Touch TT can extract text components. Touch TT can also handle partially drawn lines which cover only a small section of text area. The proposed system achieves reasonable accuracy for text extraction from moderately difficult examples from the ICDAR 2003 database and our own database.

• 정보처리학회논문지C
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• 제17C권1호
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• pp.27-36
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• 2010

웹 서비스 신청 단계에서 신청자가 실제 인간 사용자임을 확인하기 위해 사용되는 텍스트 기반 캡차(text-based CAPTCHA)의 변형된 문자를 광학문자인식 기술로 파악하는 것이 가능하기에 캡차의 신뢰성이 떨어지는 문제가 발생하고 있다. 이 문제를 해결하기 위해 제안되었던 기존의 이미지 기반 캡차(image-based CAPTCHA)에서도 여러 문제점이 존재한다. 인공지능 프로그램을 사용하여 시스템이 보유하고 있는 제한된 수의 이미지 내용을 파악함으로써 신뢰도가 떨어지는 문제가 발생할 수 있으며, 제공된 이미지에 대해 사용자가 다른 유사한 단어를 입력하는 경우에는 오답으로 판정되어 반복적으로 캡차를 시도해야 하는 불편함이 발생 할 수 있으며 또한, 사용자에게 캡차 문제를 제공하기 위해 여러 이미지 파일을 전송해야 하기에 전송 비용의 비효율성 문제가 존재한다. 이러한 기존 이미지 기반 캡차의 문제점들을 해결하기 위해 본 논문에서는 이미지와 관련 키워드 일부를 융합하여 제공하는 이미지-텍스트 융합 캡차를 제안하였다. 본 논문에서 제안한 이미지-텍스트 융합 캡차에서는 이미지와 관련된 단어의 일부분을 힌트로 활용하여 쉽게 정답을 입력할 수 있도록 사용자 편리성을 제공하며 이미지와 텍스트를 한 이미지 파일 내에 융합시켰기 때문에 전송 비용을 절약하여 효율성을 증진할 수 있다. 또한, 캡차 시스템의 신뢰성 증진을 위해 인터넷 검색으로 캡차용 이미지를 대량으로 수집하도록 하였으며 수집되는 캡차 이미지의 정확성을 유지하기 위해 필터링 과정을 거치도록 하였다. 또한, 본 논문에서는 실제 실험을 통해 제안된 이미지-텍스트 융합 캡차가 기존 이미지 기반 캡차보다 사용자에게 편리하고 신뢰성이 증진될 수 있음을 입증하였다.

• Journal of Information Processing Systems
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• 제14권2호
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• pp.418-434
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• 2018

With the increasing use of the Internet and electronic documents, automatic text categorization becomes imperative. Several machine learning algorithms have been proposed for text categorization. The k-nearest neighbor algorithm (kNN) is known to be one of the best state of the art classifiers when used for text categorization. However, kNN suffers from limitations such as high computation when classifying new instances. Instance selection techniques have emerged as highly competitive methods to improve kNN through data reduction. However previous works have evaluated those approaches only on structured datasets. In addition, their performance has not been examined over the text categorization domain where the dimensionality and size of the dataset is very high. Motivated by these observations, this paper investigates and analyzes the impact of instance selection on kNN-based text categorization in terms of various aspects such as classification accuracy, classification efficiency, and data reduction.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제8권6호
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• pp.2186-2196
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• 2014

Spam mail is one of the most general mail dysfunctions, which may cause psychological damage to internet users. As internet usage increases, the amount of spam mail has also gradually increased. Indiscriminate sending, in particular, occurs when spam mail is sent using smart phones or tablets connected to wireless networks. Spam mail consists of approximately 68% of mail traffic; however, it is believed that the true percentage of spam mail is at a much more severe level. In order to analyze and detect spam mail, we introduce a technique based on spam mail characteristics and text mining; in particular, spam mail is detected by extracting the linguistic analysis and language processing. Existing spam mail is analyzed, and hidden spam signatures are extracted using text clustering. Our proposed method utilizes a text mining system to improve the detection and error detection rates for existing spam mail and to respond to new spam mail types.

• 스마트미디어저널
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• 제2권1호
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• pp.31-36
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• 2013

A robust and efficient text extraction is very important for an accuracy of Optical Character Recognition (OCR) systems. Natural scene images with degradations such as uneven illumination, perspective distortion, complex background and multi color text give many challenges to computer vision task, especially in text extraction. In this paper, we propose a method for extraction of the text in signboard images based on a combination of mean shift algorithm and weighting scheme of hue and saturation in HSI color space for clustering algorithm. The number of clusters is determined automatically by mean shift-based density estimation, in which local clusters are estimated by repeatedly searching for higher density points in feature vector space. Weighting scheme of hue and saturation is used for formulation a new distance measure in cylindrical coordinate for text extraction. The obtained experimental results through various natural scene images are presented to demonstrate the effectiveness of our approach.

• 한국정보처리학회논문지
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• 제6권6호
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• pp.1481-1492
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• 1999

1990년대 웹 개념의 등장으로 인터넷을 개방형 네트？, 사용자 친근성 및 편의성이라는 특성을 바탕으로 급속히 일반화되면서 각종 정보를 제공하는 정보 시스템에서도 커다란 변화를 가져왔다. 웹은 텍스트 정보뿐만 아니라 이미지, 오디오, 비디오 등 멀티미디어 정보를 쉽게 제공함으로써 기존 정보 시스템의 웹 기반으로의 전환을 가속화시키게 되었다. 물론 정보 내용도 텍스트 위주의 단순 초록 정보에서 전문(Full-Text) 정보로 급속히 이전되기 시작하였으며, 전문 정보를 처리하는 다양한 문서 포맷들로 등장하기 시작하였다. 하지만, 전문 정보는 본질적으로 대용량의 시스템 메모리, 막대한 처리시간, 보다 많은 전송용량 등을 요구하게 되므로 웹 기반 전문 시스템의 구축시 이러한 요인들을 세밀하게 비교 평가하여야 한다. 따라서 본 연구는 웹 기반 정보 시스템에서 어떻게 전문을 처리할 것인가에 초점을 맞추어 문서의 통합 정보 기능을 제공하는 정보시스템을 설계 구현한다. 먼저 인터넷상에서 표준 문서형식으로 사용중이거나 개발중인 문서 포맷들의 특징을 검토하고, 정보 시스템의 관점에서 전문정보를 어떤 문서 포맷으로 처리하는 것이 적합한가를 실험하고 평가한다. 그리고 이를 기반으로 본 연구의 목적인 전문 정보를 PDF 문서로 제공하는 웹 기반 정보 시스템을 설계 구현한다.

• Educational Technology International
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• 제14권1호
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• pp.1-26
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• 2013

This study is to identify whether three types of online instruction (text-based, video-based, and video-based instruction without text) and age category have a different influence on students' comprehension and motivation. Online students were randomly assigned to one of six groups, and they attended two-week online lectures via Course Management System. The comprehension test and the short form of IMMS were implemented when 114 participants accomplished two-week online lectures. The results revealed that using instructional video in online instruction is more effective instructional medium than text only in order to promote learner's motivation. Besides, older adults aged 41-60 are significantly different from younger adults (21-40 years old) in terms of students' comprehension. Furthermore, three types of online instructions are likely to be influenced by age category.

• Communications for Statistical Applications and Methods
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• 제11권2호
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• pp.329-343
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• 2004

With advancement of computer and network, world wide web(WWW) as a medium of information communication is generalized in many fields. In educational aspect, applications of WWW as alternative media for class teachings or printed matters are increasing. In this article, we demonstrate a web-based electronic text on the 'probability and statistics' which is one of six fields of mathematics in the 7th curriculum. This text places importance on comprehension of concepts of probability and statistics as an applied science.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(4)
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• pp.359-362
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• 2002

In this paper, we propose a new feature-based text watermarking for the binary text image. The structure of specific characters from preprocessed text image are modified to embed watermark. Watermark message are embedded and detected by the following method; Hole line disconnect using the connectivity of the character containing a hole, Center line shift using the hole area and Differential encoding using difference of flippable score points. Experimental results show that the proposed method is robust to rotation and scaling distortion.

• International Journal of Contents
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• 제13권4호
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• pp.70-79
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• 2017

Images are an important element in patents and many experts use images to analyze a patent or to check differences between patents. However, there is little research on image analysis for patents partly because image processing is an advanced technology and typically patent images consist of visual parts as well as of text and numbers. This study suggests two methods for using image processing; the Scale Invariant Feature Transform(SIFT) algorithm and Optical Character Recognition(OCR). The first method which works with SIFT uses image feature points. Through feature matching, it can be applied to calculate the similarity between documents containing these images. And in the second method, OCR is used to extract text from the images. By using numbers which are extracted from an image, it is possible to extract the corresponding related text within the text passages. Subsequently, document similarity can be calculated based on the extracted text. Through comparing the suggested methods and an existing method based only on text for calculating the similarity, the feasibility is achieved. Additionally, the correlation between both the similarity measures is low which shows that they capture different aspects of the patent content.