• Title/Summary/Keyword: Rule-based approach

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A Template-based Interactive University Timetabling Support System (템플릿 기반의 상호대화형 전공강의시간표 작성지원시스템)

  • Chang, Yong-Sik;Jeong, Ye-Won
    • Journal of Intelligence and Information Systems
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    • v.16 no.3
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    • pp.121-145
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    • 2010
  • University timetabling depending on the educational environments of universities is an NP-hard problem that the amount of computation required to find solutions increases exponentially with the problem size. For many years, there have been lots of studies on university timetabling from the necessity of automatic timetable generation for students' convenience and effective lesson, and for the effective allocation of subjects, lecturers, and classrooms. Timetables are classified into a course timetable and an examination timetable. This study focuses on the former. In general, a course timetable for liberal arts is scheduled by the office of academic affairs and a course timetable for major subjects is scheduled by each department of a university. We found several problems from the analysis of current course timetabling in departments. First, it is time-consuming and inefficient for each department to do the routine and repetitive timetabling work manually. Second, many classes are concentrated into several time slots in a timetable. This tendency decreases the effectiveness of students' classes. Third, several major subjects might overlap some required subjects in liberal arts at the same time slots in the timetable. In this case, it is required that students should choose only one from the overlapped subjects. Fourth, many subjects are lectured by same lecturers every year and most of lecturers prefer the same time slots for the subjects compared with last year. This means that it will be helpful if departments reuse the previous timetables. To solve such problems and support the effective course timetabling in each department, this study proposes a university timetabling support system based on two phases. In the first phase, each department generates a timetable template from the most similar timetable case, which is based on case-based reasoning. In the second phase, the department schedules a timetable with the help of interactive user interface under the timetabling criteria, which is based on rule-based approach. This study provides the illustrations of Hanshin University. We classified timetabling criteria into intrinsic and extrinsic criteria. In intrinsic criteria, there are three criteria related to lecturer, class, and classroom which are all hard constraints. In extrinsic criteria, there are four criteria related to 'the numbers of lesson hours' by the lecturer, 'prohibition of lecture allocation to specific day-hours' for committee members, 'the number of subjects in the same day-hour,' and 'the use of common classrooms.' In 'the numbers of lesson hours' by the lecturer, there are three kinds of criteria : 'minimum number of lesson hours per week,' 'maximum number of lesson hours per week,' 'maximum number of lesson hours per day.' Extrinsic criteria are also all hard constraints except for 'minimum number of lesson hours per week' considered as a soft constraint. In addition, we proposed two indices for measuring similarities between subjects of current semester and subjects of the previous timetables, and for evaluating distribution degrees of a scheduled timetable. Similarity is measured by comparison of two attributes-subject name and its lecturer-between current semester and a previous semester. The index of distribution degree, based on information entropy, indicates a distribution of subjects in the timetable. To show this study's viability, we implemented a prototype system and performed experiments with the real data of Hanshin University. Average similarity from the most similar cases of all departments was estimated as 41.72%. It means that a timetable template generated from the most similar case will be helpful. Through sensitivity analysis, the result shows that distribution degree will increase if we set 'the number of subjects in the same day-hour' to more than 90%.

Development and Evaluation of a Document Summarization System using Features and a Text Component Identification Method (텍스트 구성요소 판별 기법과 자질을 이용한 문서 요약 시스템의 개발 및 평가)

  • Jang, Dong-Hyun;Myaeng, Sung-Hyon
    • Journal of KIISE:Software and Applications
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    • v.27 no.6
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    • pp.678-689
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    • 2000
  • This paper describes an automatic summarization approach that constructs a summary by extracting sentences that are likely to represent the main theme of a document. As a way of selecting summary sentences, the system uses a model that takes into account lexical and statistical information obtained from a document corpus. As such, the system consists of two parts: the training part and the summarization part. The former processes sentences that have been manually tagged for summary sentences and extracts necessary statistical information of various kinds, and the latter uses the information to calculate the likelihood that a given sentence is to be included in the summary. There are at least three unique aspects of this research. First of all, the system uses a text component identification model to categorize sentences into one of the text components. This allows us to eliminate parts of text that are not likely to contain summary sentences. Second, although our statistically-based model stems from an existing one developed for English texts, it applies the framework to individual features separately and computes the final score for each sentence by combining the pieces of evidence using the Dempster-Shafer combination rule. Third, not only were new features introduced but also all the features were tested for their effectiveness in the summarization framework.

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Automatic Construction of Korean Two-level Lexicon using Lexical and Morphological Information (어휘 및 형태 정보를 이용한 한국어 Two-level 어휘사전 자동 구축)

  • Kim, Bogyum;Lee, Jae Sung
    • KIPS Transactions on Software and Data Engineering
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    • v.2 no.12
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    • pp.865-872
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    • 2013
  • Two-level morphology analysis method is one of rule-based morphological analysis method. This approach handles morphological transformation using rules and analyzes words with morpheme connection information in a lexicon. It is independent of language and Korean Two-level system was also developed. But, it was limited in practical use, because of using very small set of lexicon built manually. And it has also a over-generation problem. In this paper, we propose an automatic construction method of Korean Two-level lexicon for PC-KIMMO from morpheme tagged corpus. We also propose a method to solve over-generation problem using lexical information and sub-tags. The experiment showed that the proposed method reduced over-generation by 68% compared with the previous method, and the performance increased from 39% to 65% in f-measure.

Fault Tolerant System based on Recovery Agents (회복 에이전트 기반 결함 포용 시스템)

  • Lee, Hwa-Min;Jung, Soon-Young;Yu, Heon-Chang
    • The Journal of Korean Association of Computer Education
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    • v.5 no.2
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    • pp.21-28
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    • 2002
  • This paper proposes a new approach to rollback-recovery using multi-agent in distributed computing system. Previous rollback-recovery protocols are dependent on inherent communication and operating system, which causes a decline of computing performance in distributed computing system. By using multi-agent, we propose rollback-recovery protocol that is independent on operating system. We define three kinds of agent. One is a recovery agent that performs rollback-recovery protocol after a failure. Other is an information agent that constructs domain knowledge as a rule of fault tolerance and information during failure-free operation. The other is facilitator agent that controls the efficient communication between agents. Also we propose rollback-recovery protocol using multi-agent and simulated the proposed rollback-recovery protocol using JAVA and agent communication language in CORBA environment.

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Efficient Description Method for Hanok Components Reflecting Coupling Scheme of Wooden Structure (목조건축의 결구방식을 고려한 효과적인 한옥부재 표현 기법)

  • Ahn, Eun-Young;Kim, Jae-Won
    • Journal of Korea Multimedia Society
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    • v.14 no.2
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    • pp.318-328
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    • 2011
  • This paper suggests a comprehensive method to describe architectural components for supporting Korean Traditional Building design with only small components set in CAD system. Korean traditional buildings can be classified variously based on the their size, usage and structure type(whether ornament part, namely Gongpo, is in there or not). Moreover components can be varied according to the combining rule between them. If all of these components are presented, these tremendous components rather prevent the efficient design of traditional buildings. In order to solve this problem we present object-oriented approach to describe versatile components as one template if they are same in functional aspects. From the template, many similar instances can be derived according to the attribute value. The templates are designed in order to reflect the coupling scheme between components in the relative parameters of the templates. It leads effects of minimizing error which can be occurred frequently in the process of traditional building design.

Analysis of River Flow Change Based on Some Scenarios of Global Warming (기후변화 시나리오에 의한 하천 유황의 해석)

  • Sin, Sa-Cheol
    • Journal of Korea Water Resources Association
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    • v.33 no.5
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    • pp.623-634
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    • 2000
  • This study describes results of numerical simulations on river flow response due to global warming. Forecasts of changes in climatic conditions are required to estimate the hydrologic effects of increasing trace gas concentrations in the atmosphere. However, reliable forecasts of regional climate change are unavailable. In there absence, various approaches to the development of scenarios of future climatic conditions are used. The approach in this study is to prescribe climatic changes for a river basin in a simplified manner. As a rule, such scenarios specify air temperature increases from $0^{\circ}C\;to\;4.0^{\circ}C$ and precipitation change (increase or decrease) in the range of 0% to 15%. On the basis of acceptable supposition of warming scenarios. future daily streamflow is simulated using rainfall-runoff model in the Andong Dam basin. The numerical experiments have quantitatively revealed the change of discharge at 2010, 2020, 2030 and 2050 for each warming scenarios and compared it with the results for a non-warmmg scenano.cenano.

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Analysis on the Principles for Teaching Algebra Revealed in Clairaut's (Clairaut의 <대수학 원론>에 나타난 대수 지도 원리에 대한 분석)

  • Chang, Hye-Won
    • Journal of Educational Research in Mathematics
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    • v.17 no.3
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    • pp.253-270
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    • 2007
  • by A.C. Clairaut was written based on the historico-genetic principle such as his . In this paper, by analyzing his we can induce six principles that Clairaut adopted to teach algebra: necessity and curiosity as a motive of studying algebra, harmony of discovery and proof, complementarity of generalization and specialization, connection of knowledge to be learned with already known facts, semantic approaches to procedural knowledge of mathematics, reversible approach. These can be considered as strategies for teaching algebra accorded with beginner's mind. Some of them correspond with characteristics of , but the others are unique in the domain of algebra. And by comparing Clairaut's approaches with school algebra, we discuss about some mathematical subjects: setting equations in relation to problem situations, operations and signs of letters, rule of signs in multiplication, solving quadratic equations, and general relationship between roots and coefficients of equations.

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Robust Part-of-Speech Tagger using Statistical and Rule-based Approach (통계와 규칙을 이용한 강인한 품사 태거)

  • Shim, Jun-Hyuk;Kim, Jun-Seok;Cha, Jong-Won;Lee, Geun-Bae
    • Annual Conference on Human and Language Technology
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    • 1999.10d
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    • pp.60-75
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    • 1999
  • 품사 태깅은 자연 언어 처리의 가장 기본이 되는 부분으로 상위 자연 언어 처리 부분인 구문 분석, 의미 분석의 전처리로 사용되고, 독립된 응용으로 언어의 정보를 추출하거나 정보 검색 등의 응용에 사용되어 진다. 품사 태깅은 크게 통계에 기반한 방법, 규칙에 기반한 방법, 이 둘을 모두 이용하는 혼합형 방법 등으로 나누어 연구되고 있다. 포항공대 자연언어처리 연구실의 자연 언어 처리 엔진(SKOPE)의 품사 태깅 시스템 POSTAG는 미등록어 추정이 강화된 혼합형 품사 태깅 시스템이다 본 시스템은 형태소 분석기, 통계적 품사 태거, 에러 수정 규칙 후처리기로 구성되어 있다. 이들은 각각 단순히 직렬 연결되어 있는 것이 아니라 형태소 접속 테이블을 기준으로 분석 과정에서 형태소 접속 그래프를 생성하고 처리하면서 상호 밀접한 연관을 가진다. 그리고, 미등록어용 패턴사전에 의해 등록어와 동일한 방법으로 미등록어를 처리함으로써 효율적이고 강건한 품사 태깅을 한다. 한편, POSTAG에서 사용되는 태그세트와 한국전자통신연구원(ETRI)의 표준 태그세트 간에 양방향으로 태그세트 매핑을 함으로써, 표준 태그세트로 태깅된 코퍼스로부터 POSTAC를 위한 대용량 학습자료를 얻고 POSTAG에서 두 가지 태그세트로 품사 태깅 결과 출력이 가능하다. 본 시스템은 MATEC '99'에서 제공된 30000어절에 대하여 표준 태그세트로 출력한 결과 95%의 형태소단위 정확률을 보였으며, 태그세트 매핑을 제외한 POSTAG의 품사 태깅 결과 97%의 정확률을 보였다.

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A Study of the Effect of Computer's Visual Data about Understanding Concept of Sequence with High School Student (컴퓨터 시각화 자료가 고등학생들의 수열 개념 이해에 미치는 영향)

  • Jung, In-Chul;Hwang, Woon-Gu;Kim, Taeg-Su
    • Journal of the Korean School Mathematics Society
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    • v.10 no.1
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    • pp.91-111
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    • 2007
  • This study investigated how high school students predict the rule, the sum of sequence for the concept of sequence, for the given patterns based on inductive approach using computers that provide dynamic functions and materials that are visual. Students for themselves were able to induce the formula without using the given formula in the textbook. Furthermore, this study examined how these technology and materials affect students' understanding of the concept of actual infinity for those who have the concept of the potential infinity which is the misconception of infinity in a infinity series. This study shows that students made a progress from the concept of potential infinity to that of actual infinity with technology and materials used I this study. Students also became interested in the use of computer and the visualized materials, further there was a change in their attitude toward mathematics.

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Real-Time Seam Tracking System Using a Visual Device with Vertical Projection of Laser Beam (레이저빔 수직투사 구조의 시각장치를 이용한 실시간 용접선추적 시스템)

  • Kim, Jin-Dae;Lee, Jeh-Won;Shin, Chan-Bai
    • Journal of the Korean Society for Precision Engineering
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    • v.24 no.10
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    • pp.64-74
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    • 2007
  • Because of the size and environment in the shipbuilding process, the portable type robot is required for the automatic seam tracking. For this reason, the structure of laser sensor should be considered in the initial design step and the coordinate transformation between welding robot and laser sensor, which is joint finder, must be identified exactly and the real time tracking algorithm based on these consideration could be developed. In this research, laser displacement sensor in which its structure is laser beam's vertical projection, is developed to recognize the location of weld joint. In practical applications, however, images of weld joints are often degraded because of the surface specularity or spatter. To overcome the problem, the constrained joint finding algorithm is proposed. In the approach of coordinate conversion rule for the visual feedback control among welding torch, robot body and laser sensor is applied by the same reference point method. In the real time seam tracking algorithms we propose constrained sampling method which uses look ahead distance. The RLS(Recursive Least Square) filter is applied to obtain the smooth tracking path from the sensitive edge data. From the experimental results, we could see the possibility that the developed laser sensor with proposed processing algorithm and real time seam tracking method can be used as a welding under the shipbuilding condition.