• Proceedings of the Korean Information Science Society Conference
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• 2001.10a
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• pp.262-264
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• 2001

테이블의 모든 레코드들을 삭제하는 연산과 그 연산을 취소하는 작업은 그 수행에 드는 비용이 매우 크다. 상용 데이타베이스 관리 시스템들은 테이블의 모든 레코드들을 삭제하는 연산을 신속하게 수행하기 위하여 TRUNCATE TABLE문을 제공한다. 그 문을 수행하면 레코드들을 개별적으로 삭제하지 않고 그 화일에 할당된 디스크 공간을 반환하며 그 삭제 연산을 독립된 트랜잭션으로 처리하여 즉시 완료시킨다. 따라서, 그 연산은 일단 실행되고 나면 복귀가 불가능하다. 본 논문은 DELETE문을 WHERE절 없이 사용하는 경우에 대하여 모든 레코드들을 삭제하고자 하는 화일과 동일한 구조를 가지는 하나의 빈(empty)화일을 생성하고 기존 화일과 새로이 생성한 화일 간에 화일 설명자의 내용과 디스크 공간을 교체만 후, 새로이 생성한 화일 자체를 삭제함으로써 로깅 부담을 줄이면서 신속히 모든 레코드들을 삭제하고 그 연산을 복귀할 수 있도록 하는 기법을 제시한다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2022.06a
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• pp.574-576
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• 2022

메타버스는 다수 사용자의 협업이 가능한 3 차원 가상현실 환경을 제공한다. 메타버스 공간에서의 현실과 연결된 혹은 현실이 모사된 실시간/비실시간 시뮬레이션은 비용-효율적인 이점을 가진다. 연동-시뮬레이션은 서브시스템들의 통합 시뮬레이션으로, 메타버스 공간에서의 연동-시뮬레이션을 위해 데이터-레벨, 시스템-레벨, 서비스레벨에서 기술 성능 검증 및 메타버스 윤리 검증이 필요하다. 개별 서브시스템이 윤리적으로 동작하는지 뿐만 아니라 연동된 시스템의 활용도 윤리적인가를 살펴보아야 한다. 알고리즘 및 시스템 정책이 반영되어 검증된 모델은 메타버스의 더 적은 위험성을 가지고 자동화된 디지털 사회 체계나 현실세계의 시스템에 적용되어 활용될 수 있다.

• Journal of Gifted/Talented Education
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• v.21 no.4
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• pp.861-884
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• 2011

In this study, we developed and applied 15 evaluation questions about light to 30 middle school students in K University Science Education Institute for the Gifted. Then we used the theory of knowledge space and analyzed the middle school Science Gifted Students' knowledge state about light. By schematizing the hierarchy from it, we intended to not only measure students' knowledge state about light, but use it as the basic materials to improve teaching methods. To achieve the purpose of this study, we analyzed the evaluation results and individual knowledge state and hierarchy of questions. As a result, there were different knowledge structures in the individual, and we found that we should diagnose them differently. In addition, we have had implications that it has the connection with each questions and the individual knowledge state.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.3
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• pp.423-431
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• 2016

The purpose of this study was to analyze and compare the characteristics of floor plan of Underwood hall, Appenzeller hall, and Stimson hall in Yonsei University. These buildings in Yonsei University are the representative higher educational institution buildings that were constructed by Western missionaries during the Japanese colonial period. These buildings were designed by the master plan that had been made before the construction. Therefore, these buildings have many similarities but each building has individual characteristics. This study focused on two parts. One is the characteristics of the shared space, such as like corridor, hall, and stairs. These characteristics show the differences between each building because they used different methods and locations of shared space and rooms for the floor plan to include the different functions. The second is the relationships with the floor plan and other plans like the master plan, elevation plan, and structural plan. These relationships show that each building has unique characteristics that are related to the floor plan.

• Tunnel and Underground Space
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• v.16 no.6 s.65
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• pp.451-466
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• 2006

Analysis of slope behavior concerning the structural characteristics of field rock mass can be processed by virtue of borehole information of joint orientation and position acquired from DOM drilled core. Anticipated sliding potential of pre-failed rock slope is analyzed and the regional slope instability is investigated by inspecting the hazardous joints and blocks the traces of which is projected on the cut-face. Cross section has been set at the center of rock slope and the traces of both joints and tetrahedral blocks, which potentially can induce the slope failure, are drawn to investigate the failure modes and the triggering mechanism. Automated monitoring system has been established to measure the slope movement and especially, inclinometer has been installed inside DOM borehole to analyze the slope movement by considering the internal rock structure. Algorithms for predicting the slope failure time have been reviewed and the significance of heavy rainfall on the slope behavior has been investigated.

• Journal of KIISE:Databases
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• v.28 no.1
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• pp.15-30
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• 2001

서브시퀀스 매칭은 질의 시퀀스와 유사한 서브시퀀스를 가지는 데이터 시퀀스와 해당 서브시퀀스의 위치를 찾는 문제이다. 본 논문에서는 윈도우를 구성하는 방법의 이원성을 이용한 새로운 서부시퀀스 매칭 방법인 Dual-Match는 윈도우를 구성하는 방법에 있어서 Faloutsos 등이 사용한 방법(간단히 FRM 이라한다)의 이원적 접근법이다. 즉, FRM에서는 데이터 시퀀스를 슬라이딩 윈도우로 나누고 질의 시퀀스를 디스조인트 윈도우로 나누는 방법을 사용한 반면, Dual-Match에서는 데이터 시퀀스를 디스조이트 윈도우로 나누고 질의 시퀀스를 슬라이딩 윈도우로 나누는 방법을 사용한다. FRM은 색인에 필요한 저장공간을 줄이기 위하여 개별 점 대신 최소 포함 사각형만을 저장함으로 인하여 많은 착오해답(유사하지 않은 후보 서브시퀀스)을 발생시켰다. Dual-Match는 FRM과 비슷한 크기의 저장공간에 개별 점을 직접 저장함으로써 이 문제를 해결한다. 실험결과, Dual-Match는 많은 경우에 있어서 FRM에 비하여 후보 개수를 크게 줄이고 성능을 향상시켰다. 특히, 선택률이 낮은 경우($10^{-4}$이하)에는 후보 개수를 최대 8800배 까지 줄이고, 페이지 액세스 횟수를 최대 26.9배까지 줄였으며, 성능을 최대 430배까지 향상시켰다. 또한, 동일한 크기의 색인을 생성하는데 있어서 Dual-Match는 FRM보다 4.10~25.6배 빠르게 색인을 구성하였다. 이는 색인 구성시에 CPU 오버헤드의 많은 부분을 차지하는 저차원 변환의 횟수를 FRM에 비해 크게 줄이기 때문이다. 이 같은 결과로 볼 때, Dual-Match는 대용량 데이터베이스에 대한 서부시퀀스 매칭의 성능을 크게 향상시킬 수 있는 획기적인 연구 결과라 믿는다.

• Journal of Korean Society for Geospatial Information Science
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• v.17 no.3
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• pp.89-95
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• 2009

One of the criteria provided by the law to designate the Impact Fee Zone requires that the increase rate of the development permit should exceed that of the entire locality by more than twenty percent. Since the permits are issued to scattered parcels on the individual basis, however, it renders significant difficulties in accurately figuring out the finite local areas that exceed such legal criteria. This study, in this context, tries to join the development permit time-series data with the Korea Land Information System (KLIS) so that, with the aid of the landform layer and existing infrastructure layer, it could pinpoint the local area where the development activities are concentrating. Taking a sector in Yangpyong County as the case, the study practically demonstrates as to how the designation process is geospatially processed.

• Journal of the Korean Association of Geographic Information Studies
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• v.7 no.4
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• pp.133-142
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• 2004

As the city grows in population and size, land-use plan increasingly becomes a crucial element in developing a city-wide plan. In the process of developing the land use plan, identifying the present conditions and predicting the future conditions are the most important steps. That is, to understand the phenomena of land-use activities as well as to manage uses of the land efficiently require the comprehensive land use information system. This study intends to construct the land use database utilizing the Cadastral Map and Registered Building Data and to examine and suggest the application areas of the database. The database was constructed with those of Busan Metropolitan City. Using the established data, it shows how to use the database to identify the present conditions in Busan.

• Korea Real Estate Review
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• v.24 no.1
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• pp.7-14
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• 2014

This study, as the temporal and spatial data for the real price apartment in Seoul from January 2006 to June 2013, empirically compared and analyzed the estimation result of apartment price using OLS by hedonic price model for the problem of space-time correlation, temporal autoregressive model (TAR) considering temporal effect, spatial autoregressive model (SAR) spatial effect and spatiotemporal autoregressive model (STAR) spatiotemporal effect. As a result, the adjusted R-square of STAR model was increased by 10% compared that of OLS model while the root mean squares error (RMSE) was decreased by 18%. Considering temporal and spatial effect, it is observed that the estimation of apartment price is more correct than the existing model. As the result of analyzing STAR model, the apartment price is affected as follows; area for apartment(-), years of apartment(-), dummy of low-rise(-), individual heating (-), city gas(-), dummy of reconstruction(+), stairs(+), size of complex(+). The results of other analysis method were the same. When estimating the price of real estate using STAR model, the government officials can improve policy efficiency and make reasonable investment based on the objective information by grasping trend of real estate market accurately.

• The Journal of Korean Academy of Prosthodontics
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• v.59 no.1
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• pp.134-145
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• 2021

In the case of excessively worn dentition, there is often insufficient space for the prosthesis, and if physiologically acceptable, the prosthesis can be fabricated by increasing the vertical dimension of occlusion. Various methods have been introduced to determine the vertical dimension of occlusion. Clinicians have to choose a method that can comfort the patient among several methods. A removable appliance can be used as a reversible method to ensure that the determined vertical dimension of occlusion does not cause physiological problems. When making impressions of many teeth, it is often difficult to make accurate impressions at once. In this case, after making an accurate impression of the individual teeth, a transfer coping was made and a pickup impression was taken in the oral cavity to create a master cast. In this case, a fixed partial denture was fabricated and full mouth rehabilitation was performed by increasing the vertical dimension of occlusion in a patient with excessively worn dentition and lack of space for restoration. As a result of follow-up of the patient for 7 years, satisfactory results were obtained both esthetically and functionally.