• 제목/요약/키워드: retrieval practice

검색결과 79건 처리시간 0.02초

A Study on Improving the Effectiveness of Information Retrieval Through P-norm, RF, LCAF

  • Kim, Young-cheon;Lee, Sung-joo
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제2권1호
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    • pp.9-14
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    • 2002
  • Boolean retrieval is simple and elegant. However, since there is no provision for term weighting, no ranking of the answer set is generated. As a result, the size of the output might be too large or too small. Relevance feedback is the most popular query reformulation strategy. in a relevance feedback cycle, the user is presented with a list of the retrieved documents and, after examining them, marks those which are relevant. In practice, only the top 10(or 20) ranked documents need to be examined. The main idea consists of selecting important terms, or expressions, attached to the documents that have been identified as relevant by the user, and of enhancing the importance of these terms in a new query formulation. The expected effect is that the new query will be moved towards the relevant documents and away from the non-relevant ones. Local analysis techniques are interesting because they take advantage of the local context provided with the query. In this regard, they seem more appropriate than global analysis techniques. In a local strategy, the documents retrieved for a given query q are examined at query time to determine terms for query expansion. This is similar to a relevance feedback cycle but might be done without assistance from the user.

연관색인법(聯關索引法)의 이론(理論)과 실제(實際) (Relational indexing: theory and practice)

  • 김태수
    • 정보관리학회지
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    • 제1권1호
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    • pp.25-42
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    • 1984
  • 정보(情報)의 축적(蓄積)과 검색(檢索)을 위한 개념(槪念) 조직과정(組織過程)에서는 개념(槪念) 뿐만 아니라 이들 개념간(槪念間)의 상관관계(相關關係)가 명확히 표현되어야 하며 이를 위해서는 인간(人間)의 사고과정(思考科程)에 기초해야 한다. 연관색인법(聯關索引法)에서는 9개의 연관기호(聯關記號)를 통하여 문신 중에서 각 개념간의 관계표현이 가능하며 이들 개념을 순열(順列)시키므로써 주제색인(主題索引)으로서의 기능을 수행할 수 있으며 기존의 색인(索引)시스템에 비해 검색효율의 개선(改善)을 초래할 수 있을 것이다.

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TAKES: Two-step Approach for Knowledge Extraction in Biomedical Digital Libraries

  • Song, Min
    • Journal of Information Science Theory and Practice
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    • 제2권1호
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    • pp.6-21
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    • 2014
  • This paper proposes a novel knowledge extraction system, TAKES (Two-step Approach for Knowledge Extraction System), which integrates advanced techniques from Information Retrieval (IR), Information Extraction (IE), and Natural Language Processing (NLP). In particular, TAKES adopts a novel keyphrase extraction-based query expansion technique to collect promising documents. It also uses a Conditional Random Field-based machine learning technique to extract important biological entities and relations. TAKES is applied to biological knowledge extraction, particularly retrieving promising documents that contain Protein-Protein Interaction (PPI) and extracting PPI pairs. TAKES consists of two major components: DocSpotter, which is used to query and retrieve promising documents for extraction, and a Conditional Random Field (CRF)-based entity extraction component known as FCRF. The present paper investigated research problems addressing the issues with a knowledge extraction system and conducted a series of experiments to test our hypotheses. The findings from the experiments are as follows: First, the author verified, using three different test collections to measure the performance of our query expansion technique, that DocSpotter is robust and highly accurate when compared to Okapi BM25 and SLIPPER. Second, the author verified that our relation extraction algorithm, FCRF, is highly accurate in terms of F-Measure compared to four other competitive extraction algorithms: Support Vector Machine, Maximum Entropy, Single POS HMM, and Rapier.

중국의 혁명역사기록물의 목록기술과 검색분류(2) (Bibliographical Description and Classification Indexing For Revolutionary Historical Archives in China(2))

  • 이승휘
    • 기록학연구
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    • 제5호
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    • pp.209-242
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    • 2002
  • Bibliographical Description for Revolutionary Historical Archives is created to describe records at the item level. It defines descriptive elements, punctuations, formats and methods. Descriptive elements are composed of 20 elements, each of which is either mandatory or optional. Mandatory elements are: repositories codes, documents codes, dates, creators, title, classification codes, and subject vocabularies. Abstracts were previously included in card cataloging and are removed in the computerized system. New elements, such as "uncontrolled vocabularies," "name of places," "personal names," "organizational structures" and "meetings," are added to allow keyword search. Considering that subject vocabulary searches are the most important in computerized systems, however, Guidelines for the Subject Indexing for Revolutionary Historical Archives as well as Subject Headings, as a result from the Guidelines, are created. The most extraordinary features in Chinese archival description are said to be the Guidelines for the Classification Indexing for Revolutionary Historical Archives and Materials as well as the Classification Scheme, both of which are created to allow subject search of records content. It is because Chinese practice of records management distinguishes the classification for arrangement from that for retrieval. Chinese archival description is, therefore, composed of bibliographic description rules, subject headings, and the classification scheme for retrieval.

Discovery Layer in Library Retrieval: VuFind as an Open Source Service for Academic Libraries in Developing Countries

  • Roy, Bijan Kumar;Mukhopadhyay, Parthasarathi;Biswas, Anirban
    • Journal of Information Science Theory and Practice
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    • 제10권4호
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    • pp.3-22
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    • 2022
  • This paper provides an overview of the emergence of resource discovery systems and services, along with their advantages, best practices, and current landscapes. It outlines some of the key services and functionalities of a comprehensive discovery model suitable for academic libraries in developing countries. The proposed model (VuFind as a discovery tool) performs like other existing web-scale resource discovery systems, both commercial and open-source, and is capable of providing information resources from different sources in a single-window search interface. The objective of the paper is to provide seamless access to globally distributed subscribed as well as open access resources through its discovery interface, based on a unified index. This model uses Koha, DSpace, and Greenstone as back-ends and VuFind as a discovery layer in the front-end and has also integrated many enhanced search features like Bento-box search, Geodetic search, and full-text search (using Apache Tika). The goal of this paper is to provide the academic community with a one-stop shop for better utilising and integrating heterogeneous bibliographic data sources with VuFind (https://vufind.org/vufind).

A Conceptual Framework for an Information Behavior Model Based on the Collaboration Perspective between User and System for Information Retrieval

  • Yangyuen, Wachira;Phetkaew, Thimaporn;Nuntapichai, Siwanath
    • Journal of Information Science Theory and Practice
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    • 제8권3호
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    • pp.30-46
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    • 2020
  • This research aimed (1) to study and analyze the ability of current information retrieval (IR) systems based on views of information behavior (IB), and (2) to propose a conceptual framework for an IB model based on the collaboration between the system and user, with the intent of developing an IR system that can apply intelligent techniques to enhance system efficiency. The methods in this study consisted of (1) document analysis which included studying the characteristics and efficiencies of the current IR systems and studying the IB models in the digital environment, and (2) implementation of the Delphi technique through an indepth interview method with experts. The research results were presented in three main parts. First, the IB model was categorized into eight stages, different from traditional IB, in the digital environment, which can correspond to all behaviors and be applied to with an IR system. Second, insufficient functions and log file storage hinder the system from effectively understanding and accommodating user behavior in the digital environment. Last, the proposed conceptual framework illustrated that there are stages that can add intelligent techniques to the IR system based on the collaboration perspective between the user and system to boost the users' cognitive ability and make the IR system more user-friendly. Importantly, the conceptual framework for the IB model based on the collaboration perspective between the user and system for IR assisted the ability of information systems to learn, recognize, and comprehend human IB according to individual characteristics, leading to enhancement of interaction between the system and users.

유사도 알고리즘을 활용한 시맨틱 프로세스 검색방안 (Semantic Process Retrieval with Similarity Algorithms)

  • 이홍주
    • Asia pacific journal of information systems
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    • 제18권1호
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    • pp.79-96
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    • 2008
  • One of the roles of the Semantic Web services is to execute dynamic intra-organizational services including the integration and interoperation of business processes. Since different organizations design their processes differently, the retrieval of similar semantic business processes is necessary in order to support inter-organizational collaborations. Most approaches for finding services that have certain features and support certain business processes have relied on some type of logical reasoning and exact matching. This paper presents our approach of using imprecise matching for expanding results from an exact matching engine to query the OWL(Web Ontology Language) MIT Process Handbook. MIT Process Handbook is an electronic repository of best-practice business processes. The Handbook is intended to help people: (1) redesigning organizational processes, (2) inventing new processes, and (3) sharing ideas about organizational practices. In order to use the MIT Process Handbook for process retrieval experiments, we had to export it into an OWL-based format. We model the Process Handbook meta-model in OWL and export the processes in the Handbook as instances of the meta-model. Next, we need to find a sizable number of queries and their corresponding correct answers in the Process Handbook. Many previous studies devised artificial dataset composed of randomly generated numbers without real meaning and used subjective ratings for correct answers and similarity values between processes. To generate a semantic-preserving test data set, we create 20 variants for each target process that are syntactically different but semantically equivalent using mutation operators. These variants represent the correct answers of the target process. We devise diverse similarity algorithms based on values of process attributes and structures of business processes. We use simple similarity algorithms for text retrieval such as TF-IDF and Levenshtein edit distance to devise our approaches, and utilize tree edit distance measure because semantic processes are appeared to have a graph structure. Also, we design similarity algorithms considering similarity of process structure such as part process, goal, and exception. Since we can identify relationships between semantic process and its subcomponents, this information can be utilized for calculating similarities between processes. Dice's coefficient and Jaccard similarity measures are utilized to calculate portion of overlaps between processes in diverse ways. We perform retrieval experiments to compare the performance of the devised similarity algorithms. We measure the retrieval performance in terms of precision, recall and F measure? the harmonic mean of precision and recall. The tree edit distance shows the poorest performance in terms of all measures. TF-IDF and the method incorporating TF-IDF measure and Levenshtein edit distance show better performances than other devised methods. These two measures are focused on similarity between name and descriptions of process. In addition, we calculate rank correlation coefficient, Kendall's tau b, between the number of process mutations and ranking of similarity values among the mutation sets. In this experiment, similarity measures based on process structure, such as Dice's, Jaccard, and derivatives of these measures, show greater coefficient than measures based on values of process attributes. However, the Lev-TFIDF-JaccardAll measure considering process structure and attributes' values together shows reasonably better performances in these two experiments. For retrieving semantic process, we can think that it's better to consider diverse aspects of process similarity such as process structure and values of process attributes. We generate semantic process data and its dataset for retrieval experiment from MIT Process Handbook repository. We suggest imprecise query algorithms that expand retrieval results from exact matching engine such as SPARQL, and compare the retrieval performances of the similarity algorithms. For the limitations and future work, we need to perform experiments with other dataset from other domain. And, since there are many similarity values from diverse measures, we may find better ways to identify relevant processes by applying these values simultaneously.

건설클레임 사례분석을 통한 입찰 및 계약제도 개선에 대한 연구 (A Study on the Suggestion of Construction Contract Practice in the Public Project through the analysis of Construction Claims)

  • 조영준;현창택
    • 한국건설관리학회논문집
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    • 제2권1호
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    • pp.78-87
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    • 2001
  • 최근 들어 설계서의 누락, 오류 및 불분명과 관련된 클레임이 급증하고 있으며, 다양한 건설분쟁해결방법이 모색되고 있다. 그러나 대부분의 시공자들은 발주자가 제시하는 클레임조정결과의 내용이 건설현장을 적절히 반영하지 못하였음을 이유로 이를 받아들이지 아니하고 있는 실정이다. 본 연구의 목적은 계약당사자의 책임 및 건설 클레임을 분석한 후 공공공사의 입찰 및 계약제도의 개선방안을 제시하는데 있다. 본 연구 결과 클레임을 최소화하기 위한 방안을 요약하면 다음과 같다. (1) 반복공사에서는 표준도 축적 및 재활용되어야 하고 발주자별로 특화된 시방서가 활용되어야 한다. (2) 설계자의 한계를 초과하는 부분에 대해서는 전문가책임보험제도가 도입되어야 한다. (3) 도면에 대한 개념이 구체화되어야 한다. (4) 설계업무대가기준이 정립되어야 한다. (5) 다양한 계약체계가 확립되어야 한다.

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Novel nomogram-based integrated gonadotropin therapy individualization in in vitro fertilization/intracytoplasmic sperm injection: A modeling approach

  • Ebid, Abdel Hameed IM;Motaleb, Sara M Abdel;Mostafa, Mahmoud I;Soliman, Mahmoud MA
    • Clinical and Experimental Reproductive Medicine
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    • 제48권2호
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    • pp.163-173
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    • 2021
  • Objective: This study aimed to characterize a validated model for predicting oocyte retrieval in controlled ovarian stimulation (COS) and to construct model-based nomograms for assistance in clinical decision-making regarding the gonadotropin protocol and dose. Methods: This observational, retrospective, cohort study included 636 women with primary unexplained infertility and a normal menstrual cycle who were attempting assisted reproductive therapy for the first time. The enrolled women were split into an index group (n=497) for model building and a validation group (n=139). The primary outcome was absolute oocyte count. The dose-response relationship was tested using modified Poisson, negative binomial, hybrid Poisson-Emax, and linear models. The validation group was similarly analyzed, and its results were compared to that of the index group. Results: The Poisson model with the log-link function demonstrated superior predictive performance and precision (Akaike information criterion, 2,704; λ=8.27; relative standard error (λ)=2.02%). The covariate analysis included women's age (p<0.001), antral follicle count (p<0.001), basal follicle-stimulating hormone level (p<0.001), gonadotropin dose (p=0.042), and protocol type (p=0.002 and p<0.001 for short and antagonist protocols, respectively). The estimates from 500 bootstrap samples were close to those of the original model. The validation group showed model assessment metrics comparable to the index model. Based on the fitted model, a static nomogram was built to improve visualization. In addition, a dynamic electronic tool was created for convenience of use. Conclusion: Based on our validated model, nomograms were constructed to help clinicians individualize the stimulation protocol and gonadotropin doses in COS cycles.

Spider Net 방식 Network RTK-GPS측량의 반복재현성에 대한 실험연구 (A Experimental Study on the Repeatability of Network RTK-GPS with Spider Net Type)

  • 김선철;강상구;이진덕
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2007년도 춘계학술발표회 논문집
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    • pp.37-42
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    • 2007
  • A network of MAC type was constructed in the Gyeonggi-do area to analyze the usefulness and validity of the Network RTK-GPS. Six sites were selected to conduct GPS observation for 24 hours, and by determining the ITRF of each site, coordinates were determined in connection with IGS network. Then check points which were established in Gimpo area were observed at least 7 times by Network RTK at 20 secs of retrieval intervals. The result showed high accuracy in the difference between the coordinates determined immediately by the in-field network survey and the current performance was 1-2cm. Its biggest benefit is the expanded range of survey and efficiency of practice. In summary, it is proved that a network survey has the accuracy, scalability and efficiency and it is expected that the network survey will contribute to the cadastral survey.

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