• Journal of Computing Science and Engineering
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• 제6권3호
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• pp.193-206
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• 2012

Keys play a fundamental role in all data models. They allow database systems to uniquely identify data items, and therefore, promote efficient data processing in many applications. Due to this, support is required to discover keys. These include keys that are semantically meaningful for the application domain, or are satisfied by a given database. We study the discovery of keys from SQL tables. We investigate the structural and computational properties of Armstrong tables for sets of SQL keys. Inspections of Armstrong tables enable data engineers to consolidate their understanding of semantically meaningful keys, and to communicate this understanding to other stake-holders. The stake-holders may want to make changes to the tables or provide entirely different tables to communicate their views to the data engineers. For such a purpose, we propose data mining algorithms that discover keys from a given SQL table. We combine the key mining algorithms with Armstrong table computations to generate informative Armstrong tables, that is, key-preserving semantic samples of existing SQL tables. Finally, we define formal measures to assess the distance between sets of SQL keys. The measures can be applied to validate the usefulness of Armstrong tables, and to automate the marking and feedback of non-multiple choice questions in database courses.

• 정보관리학회지
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• 제24권4호
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• pp.223-238
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• 2007

본 연구에서는 다양한 메타데이터간의 의미적 호환성을 유지하거나 개선하기 위한 기존의 방법론을 분석하고 크로스워크를 이용한 메타데이터간의 의미 호환 가능성과 한계에 대해서 검토한 후 메타데이터간의 의미 호환을 극대화하기 위한 의미적 메타데이터 매핑 프로세스를 제시하였다. 이 프로세스는 대상 메타데이터 스킴확인, 공통 데이터요소개념(DEC) 발견, 데이터요소개념에 따른 속성 그룹화, 매핑 테이블 작성 등의 네 단계로 구성된다. 국내에서 개발된 단체표준 수준의 두 인력정보 메타데이터를 대상으로 본 연구에서 제안된 프로세스를 적용하여 매핑 테이블 작성 과정을 보였다.

• 한국주거학회논문집
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• 제14권1호
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• pp.87-94
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• 2003

As important elements consisting of city streetscape, facade design on building is generally very significant. But without active acceptance and understanding of the concept that the building has a private objective as personal property, it is not easy to take an involvement into design as well as to establish reasonable and scientific standards of harmony. Therefore, for desirable streetscape planning, it is indispensable to know how to closely examine the visual harmony of already established buildings in each street and how to get the solutions for its realization. In this respect, this study is to try to examine and verify the feasibility of our present streetscape situation by experimental application of acceptable Y. Elesheshtawy's model(1997), an interpretation of quantitative index of street buildings by Gestalt theory, for the preparation of the foundation of institute and standards of building design which has social value in contributing to visual and spacious harmony in our street space without giving any damage to private property. From the result, I can assure the validity that the physical complexity, whose schema is socially and culturally different from our reality, is applicable to our actual streetscape in some extent.

• 한국실내디자인학회논문집
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• 제22권5호
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• pp.207-215
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• 2013

Due to an increase in the number of large-scale and high rise buildings, the importance of indoor location information has been highlighted. As a result, seamless three-dimensional space information, linked to various indoor and outdoor services is required. The purpose of this study is to develop a system which can edit and operate indoor space information using the IndoorGML(Geography Markup Language). It provides functions such as converting and editing authoring indoor space using the IndoorGML. Based on defined schema which is the IndoorGML international standardization work, we develop the "Editor" and "Viewer" for the IndoorGML. When indoor space is modeled in an authoring tool, a variety of topologies can be created automatically. These are available to be edited and modified. Moreover, the file of model can be saved as IndoorGML, SBM and KML file. These files are viewed by the "Viewer". Indoor LBS(Location Based Service)is served with these principles.

• 정보처리학회논문지:컴퓨터 및 통신 시스템
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• 제2권1호
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• pp.51-58
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• 2013

본 논문에서는 업무시스템 간 민감한 개인정보 전달을 위해 PKI기반 EAI 시스템을 설계, 구현하고 이에 대하여 기술한다. 이를 위해 업무시스템이 EAI 서버를 통해 안전하게 데이터를 연계하기 위해 EAI 특성에 맞는 키 교환 프로토콜을 제안한다. 키 교환을 위해서 전방향 안정성에 널리 사용되는 Diffie-Hellman기법을 적용하였으며, 키 교환 주체에 대한 인증 및 자료의 무결성을 위해 전자서명방식을 혼용한다. 또한 전체 EAI 시스템의 성능에 대한 영향을 최소화하기 위해 인증, 키 교환 및 암/복호화를 업무시스템에서만 이루어지도록 구성하고, EAI 서버는 단순히 연계통로로만 사용하도록 구성한다. 그리고 인증 및 암/복호 알고리즘은 국내표준을 준용할 수 있도록 EAI 시스템을 설계, 구현한다.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2011년도 한국컴퓨터종합학술대회논문집 Vol.38 No.1(C)
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• pp.115-118
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• 2011

코호트 연구를 위한 식사조사 프로그램에 대한 수요는 나날이 증가하고 있는 반면 프로그램의 공급은 원활하지 않은 실정이다. 이 때문에 식사조사 프로그램을 SaaS 플랫폼을 기반으로 하는 연구가 활발해 지고 있다. 대부분의 SaaS 플랫폼 기반 소프트웨어는 멀티테넌시 기술을 지원한다. 하지만 멀티테넌시 기술을 지원하기 위해서는 데이터베이스에서 여러 테넌트를 지원해야 하기 때문에 구조의 변화가 불가피 하다. 멀티테넌시를 구현하기 위해서는 논리적인 스키마로부터 물리적인 스키마로의 매핑기술이 필요하다. 데이터베이스 스키마 매핑 기술에는 Pivot table, Chunk table 등이 있는데 이 기술을 이용하여 기존의 DB구조를 변경하여 여러 테넌트가 DB를 공유할 수 있고 결합될 수 있어야 한다. 이에 본 논문에서는 SaaS 기반 식사조사를 위한 pivot table과 chunk table을 보이고 실험을 통하여 chunk table구조가 좀 더 효율적이라는 사실을 보인다.

• 한국농공학회지
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• 제40권3호
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• pp.103-112
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• 1998

In this study, database schema which is capable of maintaining various design-knowledge and applicable to the structural designs has been presented. Futhermore, by utilizing the database system, RECODSS (REinforced COncrete Design Support System) was developed as well. Knowledge-base that were formulated from the document is constructed by applying the concrete standard specifications of Korea from 1989. The basic drawing was prepared by $AutoCAD^TM$. As an inference in the preliminary design, the certainty function and the interpolation function were presented. The certainty function is made by assuming linear relations between each data while referencing $MYCIN^TM$ (expert systems). Nevertheless, the interpolation function was made by utilizing the linear Lagrange interpolation. For the search of the design-knowledge, fast search algorithm and full-text search algorithm were used, however, the design engine was programmed with C language. RECODSS was applied for designing a slab and a beam member. And the results were compared with the existing results. In conclusion, RECODSS was able to efficiently manage various design knowledge and to introduce stable design results.

• 한국CDE학회논문집
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• 제12권5호
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• pp.382-394
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• 2007

Nowadays, manufacturing industries undergo constantly growing pressures for global competitions, and they must shorten time and cost in product development and production to response varied customers' requirements. Digital virtual manufacturing is a technology that can facilitate effective product development and agile production by using digital models representing the physical and logical schema and the behavior of real manufacturing systems including products, processes, manufacturing resources and plants. For successful applications of this technology, a digital virtual factory as a well-designed and integrated environment is essential. In this paper, we developed a new classification and coding system for effective managements of digital virtual factory objects, and implement a supporting application to verify and apply it. Furthermore, a digital virtual factory layout management system based on the classification and coding system has developed using XML, Visual Basic.NET and FactoryCAD. By some case studies for automotive general assembly shops of a Korean automotive company, efficient management of factory objects and reduction of time and cost in digital virtual factory constructions are possible.

• 한국정보시스템학회지:정보시스템연구
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• 제8권1호
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• pp.27-44
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• 1999

Case-Based Reasoning(CBR) offers a new approach for developing knowledge based systems. CBR has several research issues which can be divided into two categories : (1) static issues and (2) dynamic issues. The static issues are related to case representation scheme and case data model, that is, focus on casebase which is a repository of cases. The dynamic issues, on the other hand, are related to case retrieval procedure and problem solving process, i.e. case adaptation phase. This research is forcused on retrieval procedure Traditional query processing accepts precisely specified queries and only provides exact answers, thus requiring users to fully understand the problem domain and the casebase schema, but returning limited or even null information if the exact answer is not available. To remedy such a restriction, extending the classical notion of query answering to approximate query answering(AQA) has been explored. AQA can be achieved by neighborhood query answering or associative query answering. In this paper, neighborhood query answering technique is used for AQA. To reinforce the CBR process, a new retrieval procedure(cooperative CBR) using neighborhood query answering is proposed. An neighborhood query answering relaxes a query scope to enlarge the search range, or relaxes an answer scope to include additional information. Computer Aided Process Planning(CAPP) is selected as cooperative CBR application domain for test. CAPP is an essential key for achieving CIM. It is the bridge between CAD and CAM and translates the design information into manufacturing instructions. As a result of the test, it is approved that the problem solving ability of cooperative CBR is improved by relaxation technique.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.340-342
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• 2003

Location based services based on positions of moving objects are expanding the business area gradually. The location is included all estimate position of the future as well as the position of the present and the past. Location based routing service is active business application in which the position information of moving objects is applied efficiently. This service includes the trajectory of past positions, the real-time tracing of present position of special moving objects, and the shortest and optimized paths combined with map information. In this paper, we describes the location based routing services is extend in distributed web GIS environment. Web GIS service systems provide the various GIS services of analyzing and displaying the spatial data with friendly user - interface. That is, we propose the efficient architecture and technologies for servicing the location based routing services in distributed web GIS environment. The position of moving objects is acquired by GPS (Global Positioning System) and converted the coordinate of real world by map matching with geometric information. We suppose the swapping method between main memory and storages to access the quite a number of moving objects. And, the result of location based routing services is wrapped the web-styled data format. We design the schema based on the GML. We design these services as components were developed in object-oriented computing environment, and provide the interoperability, language-independent, easy developing environment as well as re - usability.