• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2007년도 공동학술대회 논문집
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• pp.241-244
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• 2007

Cement-grouts are injected into limestone cavities beneath the road in the project area, in order to improve strength and reduce permeability; the extent to which grout has penetrated in cavities need to be monitored in order to determined effectiveness of cement-grout. Geophysical approaches, offer great potential for monitoring the grout injection process in a fast and cost-effective way as well as showing whether the grout has successfully achieved the target. This paper presents the ability of surface electrical resistivity to investigate the verification of the grout placement. In order to image the cement-grout, time-lapse surface electrical resistivity surveys were conducted to compare electrical resistivity images before and after injection. Cement-grout was imaged as anomalies exhibiting low resistivity than the surrounding rocks. In accordance with field monitoring, laboratory study was also designed to monitor the resistivity changes of cement-grout specimens with time-lapse. Time-lapse laboratory measurements indicated that electrical methods are good tool to identify the grouted zone. Pre-and post grouting electrical images showed significant changes in subsurface resistivity at grouted zone. The study showed that electrical resistivity imaging technology can be a useful tool for detecting and evaluating changes in subsurface resistivity due to the injection of the grout.

• 한국환경교육학회지:환경교육
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• 제24권1호
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• pp.102-113
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• 2011

The role of teachers has been explicitly emphasized to implement the vision of sustainable development(SD). Also, it is very important to understand the way student teachers understand SD and how they interpret their own professional task in terms of SD, usually referred to as education for sustainable development(ESD). This study investigated student teachers' perceptions of SD and ESD using group interview. Key findings include, first, that they think SD as development which does not exceed the limits of natural environment, and as wise management of resources/protection of environment for future generations. They also think SD as good thing though they don't understand the contested nature of SD. Second they think ESD as education about SD, but some student teachers say they can't explain ESD. Many student teachers prefer field trip to local examples for both elementary school students and themselves. Also they will teach only what the textbook says about SD and ESD during their school placement and as teachers. So it will be the beginning of ESD in school to include SD in the curriculum for students and student teachers. It is suggested to study student teachers' perception of SD focussing on how they think the relationship between protection of environment and economic growth.

• 한국건축시공학회지
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• 제13권4호
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• pp.400-406
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• 2013

In high-rise buildings, high-strength concrete is widely used to reduce the section of structure members under axial load. Also, the price increase of materials is very important item in the high-rise buildings. Especially, concrete used high-pressure pump due to consecutive structural assembly. Unlike slump type of ordinary concrete, high strength concrete has different properties of concrete pumping due to viscosity. However, there have been no Korean studies on the pumping properties of high strength concrete. Therefore, this paper measures the friction factor of high strength concrete with changes in the pressure of concrete pumping. We analyzed the trends of the friction factor based on changes in the pressure of concrete pumping, and then calculated the quantity of concrete deposited for each specified concrete strength and location of placement. After comparing these results with the quantity of concrete deposited measured in field, we evaluated the pumping properties of high strength concrete. Through the tests and the review, we attempt to suggest some basic information for the In-Situ application of high strength concrete.

• 정보관리학회지
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• 제9권1호
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• pp.55-82
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• 1992

정보검색분야의 연구는 정보를 소장, 처리하는 방법 및 기술의 영향을 받아 변화할 수 있다는 가설아래 그 기술적 환경의 변화가 뚜렷하게 나타난 1980년대의 정보검색분야의 지적 구조 및 지적 변화를 저자동시인용기법을 이용하여 고찰하였다. 영어문화권의 정보학자 22명으로 정보검색분야의 영역을 나타내었고, 다차원 축적기법과 군집분석을 통하여 이차원 공간상에 하위주제간의 관계를 표시하였다. 이차원 지도상에 나타난 저자의 군집과 저자들의 위치는 저자 저작물의 전반적인 성격과 상응하여 잘 나타났으며, 시간의 경과에 따라 뚜렷한 지적 재구성을 보여주었다.

• 디지털융복합연구
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• 제17권9호
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• pp.383-389
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• 2019

본 연구는 대학홍보 및 정보안내를 위해 용인대학교 교내에 설치된 디지털 인포메이션 디스플레이의 이용행태 분석을 통해 문제점을 파악하고 보다 효율적인 정보제공의 역할을 할 수 있는 이용자중심의 콘텐츠 개선방안을 제시하고자 하였다. 현장관찰과 설문조사를 통한 연구결과, 이용자 중심의 주요 콘텐츠를 추출하여 정보의 중요도 및 시간대에 맞는 맞춤 콘텐츠를 차등노출하고 체류시간이 많은 공간에 디스플레이를 재배치함으로써 정보전달을 극대화하는 방안을 제시하였다. 이를 통해 대학교 내 뿐만 아니라 다양한 공공공간에 설치되는 인포메이션 디스플레이의 효과적인 정보전달을 위한 콘텐츠 구성방안의 가이드라인을 제시하고자 하였다.

• 한국의류학회지
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• 제44권5호
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• pp.950-968
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• 2020

This study derives the modern characteristics of the paisley ornament through an analysis of the paisley ornament shown in fashion since the 2010s based on a theoretical review of the paisley ornament used in Kashmir India shawls for artistic inspiration in the fashion-textile field. It classified the paisley ornament in fashion since the 2010s into types of 'basic structure of body and coif', 'abnormal paisley ornament shapes', 'complex structure of paisley ornament', 'complex structure with other motif', 'a pair of symmetrical reflection motif', 'regular of repetitive arrangement', 'complex arrangement of irregularity and regularity' and 'free arrangement of irregularity'. A comparative analysis with the historical paisley ornament shows that paisley ornaments have contemporary characteristics like 'Bisector structure of centerline in criterion of the body', 'Composite structure of extended 1-repeat', and 'Free structure of engineered placement'. A modern design was inspired by the historical art forms; however, it was used in free utilization of motifs and patterns in terms of size, direction, proportion and space. These were the expression of a design identity that originated from the aesthetic ability and career of a designer as well as the technology of computer programs for the improvements in time and cost efficiency.

• Advances in concrete construction
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• 제11권5호
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• pp.397-407
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• 2021

This paper investigates the optimal sensor placements and capabilities of this procedure for dynamic characteristics identification of arch dams. For this purpose, a prototype arch dam is constructed in laboratory conditions. Berke arch dam located on the Ceyhan River in city of Osmaniye is one of the highest arch dam constructed in Turkey is selected for field verification. The ambient vibration tests are conducted using initial candidate sensor locations at the beginning of the study. Enhanced Frequency Domain Decomposition and Stochastic Subspace Identification methods are used to extract experimental dynamic characteristics. Then, measurements are repeated according to optimal sensor locations of the dams. These locations are specified using the Effective Independence Method. To determine the optimal sensor locations, the target mode shape matrices which are obtained from ambient vibration tests of the selected dam with a large number of accelerometers are used. The dynamic characteristics obtained from each ambient vibrations tests are compared with each other. It is concluded that the dynamic characteristics obtained from initial measurements and those obtained from a limited number of sensors are compatible with each other. This situation indicates that optimal sensor placements determined by the Effective Independence Method are useful for dynamic characteristics identification of arch dams.

• 시스템엔지니어링학술지
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• 제17권2호
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• pp.49-60
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• 2021

The Core Protection Calculator System (CPCS) is vital for plant safety as it ensures the required Specified Acceptance Fuel Design Limit (SAFDL) are not exceeded. The CPCS generates trip signals when Departure from Nucleate Boiling Ratio (DNBR) and Local Power Density (LPD) exceeds their predetermined setpoints. These setpoints are established based on the operating margin from the analysis that produces the SAFDL values. The goal of this research is to create a simplified CPCS that optimizes operating margin for I-SMRs. Because the I-SMR is compact in design, instrumentation placement is a challenge, as it is with Ex-core detectors and RCP instrumentation. The proposed CPCS addresses the issue of power flux measurement with In-Core Instrumentation (ICI), while flow measurement is handled with differential pressure transmitters between Steam Generators (SG). Simplification of CPCS is based on a Look-Up-Table (LUT) for determining the CEA groups' position. However, simplification brings approximations that result in a loss of operational margin, which necessitates compensation. Appropriate compensation is performed based on the result of analysis. FPGAs (Field Programmable Gate Arrays) are presented as a way to compensate for the inadequacies of current systems by providing faster execution speeds and a lower Common Cause Failure rate (CCF).

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제49권3호
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• pp.114-124
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• 2023

Dental implants have been utilized for many years to treat individuals with missing teeth. To optimize the long-term success rate of such implants, new designs, surfaces, and materials have been analyzed. It is important for the clinician to have a background in the field of implant surface design, to be familiar with the strengths and limitations of the available options, and to be aware of the alterations in surface structure that may occur following installation. This article provides a detailed review of the structure and the surface characteristics of dental implants, the modifications of implant surface, as well as the methods of evaluating implant surface structure. Moreover, it provides information concerning the structural changes that may take place at the time of dental implant placement. It is important for clinicians to be aware of such changes to plan and execute implant procedures with the highest possible success and implant survival rates.

• 한국의학물리학회지:의학물리
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• 제12권2호
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• pp.177-184
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• 2001

방사선 치료목표는 정해진 방사선량을 병변부위에 정확하게 조사시키고 주위 정상조직에는 방사선이 조사되지 알도록 하는 것이다. 이때에 조사야 배치, 차폐체 배치의 부정확성, 환자의 움직임 등으로 병변부위와 치료부위 사이에서 변위오차가 발생할 수 있다. 본 연구에서는 방사선 치료 위치의 확인을 위한 방법으로서 랜드마크를 이용하여 포탈영상과 x선 시뮬레이터 영상을 비교하는 알고리즘을 개발하여 방사선 치료 시 발생하는 부정확도를 이동, 스케일, 회전 정도로 나타내어 정량적으로 확인하였다. 등록 알고리즘은 랜드마크 정합 후 필드 경계 정합에 의해 두 영상의 변위오차를 분석하는 순서로 구현된다. 우선 각 영상의 두개의 랜드마크를 이은 대응선분들을 이용하여 변환변수 (이동, 스케일, 회전)를 구하여 랜드마크를 정합하였다. 다음으로 포탈영상의 필드경계를 추출한 후 $\rho$-$\theta$ technique을 적용하여 두 필드의 변위오차를 계산하였다. 팬톰 포탈영상에 적용하여 이동에서 2mm 이내, 회전에서 1$^{\circ}$ 이내, 스케일에서 1% 이내의 오차를 보였다. 본 연구의 결과를 통하여 방사선 치료 시 시뮬레이터 영상과 포탈영상을 정량적으로 분석함으로서, 환자 치료의 정확도 확인 연구에 기여할 수 있을 것으로 사료된다.