• Title/Summary/Keyword: retrieval effectiveness

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Automated Essay Grading: An Application For Historical Malay Text

  • Syed Mustapha, S.M.F.D;Idris, N.
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • 2001.01a
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    • pp.237-245
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    • 2001
  • Automated essay grading has been proposed for over thirty years. Only recently have practical implementations been constructed and tested. This paper investigated the role of the nearest-neighbour algorithm within the information retrieval as a way of grading the essay automatically called Automated Essay Grading System. It intended to offer teachers an individualized assistance in grading the student\`s essay. The system involved several processes, which are the indexing, the structuring of the model answer and the grade processing. The indexing process comprised the document indexing and query processing which are mainly used for representing the documents and the query. Structuring the model answer is actually preparing the marking scheme and the grade processing is the process of assessing the essay. To test the effectiveness of the developed algorithms, the algorithms are tested against the History text in Malay. The result showed that th information retrieval and the nearest-neighbour algorithm are practical combination that offer acceptable performance for grading the essay.

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Document Retrieval using Concept Network (개념 네트워크를 이용한 정보 검색 방법)

  • Hur, Won-Chang;Lee, Sang-Jin
    • Asia pacific journal of information systems
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    • v.16 no.4
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    • pp.203-215
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    • 2006
  • The advent of KM(knowledge management) concept have led many organizations to seek an effective way to make use of their knowledge. But the absence of right tools for systematic handling of unstructured information makes it difficult to automatically retrieve and share relevant information that exactly meet user's needs. we propose a systematic method to enable content-based information retrieval from corpus of unstructured documents. In our method, a document is represented by using several key terms which are automatically selected based on their quantitative relevancy to the document. Basically, the relevancy is calculated by using a traditional TFIDF measure that are widely accepted in the related research, but to improve effectiveness of the measure, we exploited 'concept network' that represents term-term relationships. In particular, in constructing the concept network, we have also considered relative position of terms occurring in a document. A prototype system for experiment has been implemented. The experiment result shows that our approach can have higher performance over the conventional TFIDF method.

Query Optimization for retrieval of reusable components using Simulated Annealing (시뮬레이티드 어닐링을 이용한 재사용 부품 추출의 질의 최적화)

  • 이은주;이병정;이숙희;우치수
    • Proceedings of the Korean Information Science Society Conference
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    • 1998.10b
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    • pp.523-525
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    • 1998
  • 소프트웨어 개발의 생산성과 신뢰성을 향상시키기 위해 소프트웨어 재사용이 필요하며, 소프트웨어 재사용에서는 원하는 부품을 정확하고 신속하게 검색하는 것이 매우 중요하다. 본 논문에서는 재사용 라이브러리에서 재사용 부품 추출을 위하여 정보추출 기법의 질의어 최적화 과정에 시뮬레이티드 어닐링을 적용하였다. 최적화 과정은 적합성 피이드백(relevance feedback)과 벡터 공간 모델을 적용하여 선형추출(linear retrieval)을 할 때 질의어 용어 가중치를 최적화 하는 것으로써, 실험을 통하여 최적화한 질의어의 추출효과도(retrieval effectiveness)척도가 최적화 하지 않은 경우의 척도보다 결과가 매우 좋다는 것을 보인다. 그리고 언덕 오르기(Hill-climbing)알고리즘을 사용한 방법과 비교, 분석한다.

Content-Based Image Retrieval Based on Relevance Feedback and Reinforcement Learning for Medical Images

  • Lakdashti, Abolfazl;Ajorloo, Hossein
    • ETRI Journal
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    • v.33 no.2
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    • pp.240-250
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    • 2011
  • To enable a relevance feedback paradigm to evolve itself by users' feedback, a reinforcement learning method is proposed. The feature space of the medical images is partitioned into positive and negative hypercubes by the system. Each hypercube constitutes an individual in a genetic algorithm infrastructure. The rules take recombination and mutation operators to make new rules for better exploring the feature space. The effectiveness of the rules is checked by a scoring method by which the ineffective rules will be omitted gradually and the effective ones survive. Our experiments on a set of 10,004 images from the IRMA database show that the proposed approach can better describe the semantic content of images for image retrieval with respect to other existing approaches in the literature.

A Fuzzy Retrieval System to Facilitate Associated Learning in Problem Banks (문제 은행에서 연상학습을 지원하는 퍼지 검색 시스템)

  • Choi, Jae-hun;Kim, ji-Suk;Cho, Gi-Hwan
    • Journal of KIISE:Software and Applications
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    • v.29 no.4
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    • pp.278-288
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    • 2002
  • This paper presents a design and implementation of fuzzy retrieval system that could support an associated learning in problem banks. It tries to retrieve some of the problems conceptually related to specific semantics described by user's queries. In particular, the problem retrieval system employs a fuzzy thesaurus which represents relationships between domain dependent vocabularies as fuzzy degrees. It would keep track of characteristics of the associated learning, which should guarantee high recall and acceptable precision for retrieval effectiveness. That is, since the thesaurus could make a vocabulary mismatch problem resolved among query terms and document index terms, this retrieval system could take a chance to effectively support user's associated teaming. Finally, we have evaluated whether the fuzzy retrieval system is appropriate for the associated teaming or not, by means of its precision and recall rate point of view.

An Extended Faceted Classification Scheme and Hybrid Retrieval Model to Support Software Reuse (소프트웨어 재사용을 지원하는 확장된 패싯 분류 방식과 혼합형 검색 모델)

  • Gang, Mun-Seol;Kim, Byeong-Gi
    • The Transactions of the Korea Information Processing Society
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    • v.1 no.1
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    • pp.23-37
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    • 1994
  • In this paper, we design and implement the prototype system, and propose the Extended Faceted Classification. Scheme and the Hybrid Retrieval Method that support classifying the software components, storing in library, and efficient retrieval according to user's request. In order to designs the classification scheme, we identify several necessary items by analyzing basic classes of software components that are to be classified. Then, we classify the items by their characteristics, decide the facets, and compose the component descriptors. According to their basic characteristics, we store software components in the library by clustering their application domains and are assign weights to the facets and its items to describe the component characteristics. In order to retrieve the software components, we use the retrieval-by-query model, and the weights and similarity for easy retrieval of similar software components. As the result of applying proposed classification scheme and retrieval model, we can easily identify similar components and the process of classification become simple. Also, the construction of queries becomes simple, the control of the size and order of the components to be retrieved possible, and the retrieval effectiveness is improved.

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The Analysis of Visual Descriptors for Content-based Video Retrieval (내용기반 비디오 검색을 위한 MPEG-7 비주얼 디스크립터 분석)

  • Kim, Seong-Hee
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.16 no.2
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    • pp.157-175
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    • 2005
  • The main purpose of this paper is to explain and analyze visual descriptors of MPEG-7 for representing multimedia content. This study describes MPEG-7 visual descriptors that are made of color, shape, texture, and motion using some examples and application areas in detail. As a result, those visual descriptors can represent the rich and deep features in multimedia contents domain. Also, the use of those descriptors will increase the retrieval effectiveness as well as the interoperability among systems through the consistency of the content representation.

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Efficient Image Search using Advanced SURF and DCD on Mobile Platform (모바일 플랫폼에서 개선된 SURF와 DCD를 이용한 효율적인 영상 검색)

  • Lee, Yong-Hwan
    • Journal of the Semiconductor & Display Technology
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    • v.14 no.2
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    • pp.53-59
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    • 2015
  • Since the amount of digital image continues to grow in usage, users feel increased difficulty in finding specific images from the image collection. This paper proposes a novel image searching scheme that extracts the image feature using combination of Advanced SURF (Speed-Up Robust Feature) and DCD (Dominant Color Descriptor). The key point of this research is to provide a new feature extraction algorithm to improve the existing SURF method with removal of unnecessary feature in image retrieval, which can be adaptable to mobile system and efficiently run on the mobile environments. To evaluate the proposed scheme, we assessed the performance of simulation in term of average precision and F-score on two databases, commonly used in the field of image retrieval. The experimental results revealed that the proposed algorithm exhibited a significant improvement of over 14.4% in retrieval effectiveness, compared to OpenSURF. The main contribution of this paper is that the proposed approach achieves high accuracy and stability by using ASURF and DCD in searching for natural image on mobile platform.

Topic Level Disambiguation for Weak Queries

  • Zhang, Hui;Yang, Kiduk;Jacob, Elin
    • Journal of Information Science Theory and Practice
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    • v.1 no.3
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    • pp.33-46
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    • 2013
  • Despite limited success, today's information retrieval (IR) systems are not intelligent or reliable. IR systems return poor search results when users formulate their information needs into incomplete or ambiguous queries (i.e., weak queries). Therefore, one of the main challenges in modern IR research is to provide consistent results across all queries by improving the performance on weak queries. However, existing IR approaches such as query expansion are not overly effective because they make little effort to analyze and exploit the meanings of the queries. Furthermore, word sense disambiguation approaches, which rely on textual context, are ineffective against weak queries that are typically short. Motivated by the demand for a robust IR system that can consistently provide highly accurate results, the proposed study implemented a novel topic detection that leveraged both the language model and structural knowledge of Wikipedia and systematically evaluated the effect of query disambiguation and topic-based retrieval approaches on TREC collections. The results not only confirm the effectiveness of the proposed topic detection and topic-based retrieval approaches but also demonstrate that query disambiguation does not improve IR as expected.

Photo Retrieval System using Combination of Smart Sensor and Visual Descriptor (스마트 센서와 시각적 기술자를 결합한 사진 검색 시스템)

  • Lee, Yong-Hwan;Kim, Heung-Jun
    • Journal of the Semiconductor & Display Technology
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    • v.13 no.2
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    • pp.45-52
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    • 2014
  • This paper proposes an efficient photo retrieval system that automatically indexes for searching of relevant images, using a combination of geo-coded information, direction/location of image capture device and content-based visual features. A photo image is labeled with its GPS (Global Positioning System) coordinates and direction of the camera view at the moment of capture, and the label leads to generate a geo-spatial index with three core elements of latitude, longitude and viewing direction. Then, content-based visual features are extracted and combined with the geo-spatial information, for indexing and retrieving the photo images. For user's querying process, the proposed method adopts two steps as a progressive approach, filtering the relevant subset prior to use a content-based ranking function. To evaluate the performance of the proposed scheme, we assess the simulation performance in terms of average precision and F-score, using a natural photo collection. Comparing the proposed approach to retrieve using only visual features, an improvement of 20.8% was observed. The experimental results show that the proposed method exhibited a significant enhancement of around 7.2% in retrieval effectiveness, compared to previous work. These results reveal that a combination of context and content analysis is markedly more efficient and meaningful that using only visual feature for image search.