• Journal of Korea Water Resources Association
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• v.44 no.9
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• pp.753-763
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• 2011

Allocated water storage of dam at the planning and design stage does not seem to be maintained well at the operation stage because of unexpected critical reasons. A dam is likely to be subject to negative effects caused by changes of dam operation conditions and it is hardly avoidable. Therefore, it must be timely improved to recover its original functions and looked for better alternatives to keep its original roles. Specifically the improper management of river condition degrades flood control capability in a dam and river eco-system. The dam downstream river improvement work is needed for normalizing dam functions and its valuations. This study focuses on estimating water use benefits from recovering its own effective storage buffer restricted for flood control. As the results, the water supply and the hydropower benefits in Imha, Daechung and Youngdam Dam are recovered totally by 19.9 million $m^3$/year and 20.8 GWh/year respectively. Also those results are used for the basic information of the economic analysis in the dam downstream river improvement work.

• Journal of Korean Tunnelling and Underground Space Association
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• v.24 no.6
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• pp.637-658
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• 2022

TBM tunnel is simple with the iterative process of excavating the ground, building a segment ring-build, and backfilling. Drill & Blast, a conventional tunnel construction method, is more complicated than the TBM tunnel and has some restrictions because it repeats the inspection, drilling, charging, blasting, ventilation, muck treatment, and installation of support materials. However, the preparation work for excavation requires time and cost based on a very detailed plan compared to Drill & Blasting, which reinforces the ground and forms a tunnel after the formation of tunnel portal. This is because the TBM equipment for excavating the target ground determines the success or failure of the construction. If the TBM, an expensive order-made equipment, is incorrectly configured at the assembly stage, it becomes difficult to excavate from the initial stage as well as the main excavation stage. When the assembled shield TBM equipment is dismantled again, and a situation of re-assembly occurs, it is difficult throughout the construction period due to economic loss as well as time. Therefore, in this study, the layout and plan of the site and the assembly process for each major part of the TBM equipment were reviewed for the assembly of slurry shield TBM to construct the largest diameter road tunnel in domestic passing through the Han River and minimized interference with other processes and the efficiency of cutter head assembly and transport were analyzed and improved to suit the site conditions.

• Journal of Digital Convergence
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• v.18 no.6
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• pp.187-196
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• 2020

We tried to do research on main views(risk and knowledge-based) and propose user knowledge as a factor to be managed in order to strengthen the performance. This study empirically analyzed the user-related and project management risk that affect the IT project performance, and verified user knowledge as a moderating variable. The survey was conducted for respondents who have experience on IT Project of public sector and data were analyzed by Smart PLS 3.0. The results show that low user-related and project management risks have a positive effect on performance. In addition, user knowledge has been shown to enhance the impact of two risks on performance. These findings are meaningful in that they emphasize the importance of user knowledge in public-sector IT projects, as well as the repeated verification of integrated research results.

• Korean Journal of Childcare and Education
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• v.9 no.6
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• pp.129-150
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• 2013

The issue of child care in family policy is one of the most important agendas. It is the primary task for a welfare state to form such conditions as socializing it to ensure labor rights and parental rights. The aim of this study is to review any controversies in the agenda of free choice in child care. But real 'free choice' comes true when all community members as individuals are able to enjoy their rights as both workers and parents without any restriction and sexual discrimination in the labor market. But in reality 'free choice' has not been realized in our society. This study is based on the analysis of these issues in free choice - the concepts of liberty, equity and equality, the role of the state, financial efficiency and the status of women in the labor market. Based on the analysis of the issues in accordance with the criteria, I suggest some policy recommendations: adequate and sufficient child care services, the introduction of univer sal child benefits and the expansion of public child care facilities.

• Journal of the Korean Society of Hazard Mitigation
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• v.4 no.2 s.13
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• pp.47-52
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• 2004

Whereas The masonry buildings are safe under gravity loads, most of the masonry buildings in Korea have many structural defects under a lateral load due to an earthquake acceleration. But there is no earthquake resistant design code for the Masonry in Korea. Therefore it may be necessary to be set up an seismic code and be suggested for reinforcing methods for existing masonry buildings. The purpose of this paper is to investigate seismic capacity of reinforced masonry buildings subjected to earthquake load. The typical two models of the masonry building in Korea are selected through a site investigation. On the basis of test results, the fiber reinforcing effect of the two models was considerable. The maximum base shear force and deformation capacity for RM were remarkably increased. It was found that the pier rocking failure was a dominant mode for the RM buildings during a seismic excitation.

• Journal of Korean Medical classics
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• v.19 no.3
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• pp.65-99
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• 2006

송대통치자희환의약병중견의학적발전. 축소궁정의료궤구(縮小宮廷醫療机構), 각확대평민의료여의약유관적자선궤구이개선백성의료조건적정책방향흔진보적. 장의적엄범지수집, 교정(校訂), 편찬(編纂), 반포이수존의학문헌(頒布以收存醫學文獻), 병차위의학적전파화보급작출봉헌. ${\ulcorner}$내경(內經)${\lrcorner}$, ${\ulcorner}$상한(傷寒)${\lrcorner}$ 등기초이론적연구방면상야운용(等基礎理論的硏究方面上也運用), 금원시기성위료학술쟁론적기출, 저시송대의정상최성공적정책(這是宋代醫政上最成功的政策). 유정부엄구약물, 수정본초병건립제약공창화약점(修訂本草幷建立製藥工廠和約店), 전매약물(專賣藥物), 개혁제형, 이발전'성약'(以發展'成葯'), 통일용약적규범등(統一用藥的范等), 저양적조시향약물적발전화의약적민중화흔대적영향. 의약교육방면상(醫藥敎育方面上), 재태의국화국자감리건립적'의학'교육제도유흔다건공, 궤구적예속, 전과(專科) 적분과(的分科), 고시제도(考試制度), 학교관리등도적료신경험(學校管理等都積了新驗), 의학상이'삼사법'(醫學上以'三舍法') '공액'위려의학교육적조시('貢額'爲勵醫學敎育的措施), 저치득긍정적(這値得肯定的). 송대의학교육상야유과착(宋代醫學敎育上也有過錯). 비여(譬如), 인제도적존폐이유실교육적연속성(因制度的存廢而有失敎育的連續性), 이방애의약교육경금적척축화계승(以妨碍醫藥敎育經驗的積蓄和繼承), 불단결핍잠력, 상실동력이차몰건립전문약학교육(喪失動力而且沒建立專門藥學敎育). 대부분수요의정궤구적건립(大部分需要醫政机構的建立). 단시유례속관사흔옹제적문제, 인위피상부소속궤관소견체소이불구통일적지도화협조, 최고의정궤구'한임의관원'야몰유통제의약궤구적권한(最高醫政机構'翰林醫官院'也沒有統制醫藥机構的權限), 직책중복(職責重複), 인원과잉(人員過剩), 의관원본신이야유흔다과잉리인원, 부구엄격적관리제도. 인비송대의관관리방면상강락료총효율(因比宋代醫官管理方面上降落了總效率).

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.142-144
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• 2008

한국전력공사(이하 한전)에서는 배전계통의 최적운영을 위하여 계통운영에 필요한 기술을 발굴하여 축적하는데 많은 노력을 기울여 왔으며, 계통운영의 핵심 툴인 배전자동화 시스템을 통하여 관련기술을 축적해오고 있다. 우리나라처럼 배전자동화 시스템을 전력회사에서 자체적으로 개발하여 활용하는 사례는 전 세계적으로 유일하며, 이를 기반으로 해외 전력시장에 배전자동화 시스템을 수출하기 위하여 활발한 활동을 지속적으로 추진되고 있다. 배전자동화 시스템을 이용하면 원격으로 현장에 있는 배전자동화기기를 감시, 제어, 조작, 정정이 가능한 기본기능이 구현가능하고, 각종 계통운영에 필요한 기술계산, 즉 전압강하계산, 보호협조검토, 표준조작지시서(SOP)의 생성, 상시개방점 위치조정으로 손실최소화, 분산전원 연계계통 기술검토의 자동처리가 가능해진다. 기술계산프로그램은 최초 개발 당시인 2002년에는 배전자동화시스템 주장치가 설치된 장소인 온라인 상태에서만 사용이 가능하여 사용상 제약을 가지고 있었으나, 이를 개선하고자 2006년 10월 배전자동화기반 오프라인형 기술계산프로그램을 개발하였고 이를 지속적으로 업그레이드를 추진하여 활용해오고 있다. 배전자동화기반 오프라인형 기술계산프로그램은 배전자동화주장치에서 데이터를 추출하여 배전자동화주장치가 아닌 일반PC나 노트북에서도 배전자동화시스템에 내장된 배전계통 정보 즉, 선로길이 및 전력선 제원 등을 직접 이용하므로 각종 기술계산을 신속하고 정확하게 수행하는 것이 가능하게 되었다. 따라서 이를 지속적으로 활용하고 성능개선을 추진하여 배전계통 운영시 신뢰도 제고에 크게 기여할 것으로 기대되고 있다.

• Journal of Korean Society of Transportation
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• v.27 no.4
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• pp.127-135
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• 2009

Most traffic information that drivers receive while driving are stored in their short-term memory and disappear within a few seconds. Contemporary modeling approaches using a dummy variable can't fully explain this phenomenon. As such, this study proposes to use utility functions of real-time in-vehicle traffic safety information (IVTSI), analyzing its safety impacts based on empirical data from an on-site driving experiment at signalized intersection approach with a limited visibility. For this, a driving stability evaluation model is developed based on driver's driving speed choice, applying an ordered probit model. To estimate the specified utility functions, the model simultaneously accounts for various factors, such as traffic operation, geometry, road environment, and driver's characteristics. The results show three significant facts. First, a normal density function (exponential function) is appropriate to explain the utility of IVTSI proposed under study over time. Second, the IVTSI remains in driver's short-term memory for up to nearly 22 second after provision, decreasing over time. Three, IVTSI provision appears more important than the geometry factor but less than the traffic operation factor.

• Journal of Korea Water Resources Association
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• v.31 no.1
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• pp.105-113
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• 1998

Reservoir operation during flood period can be divided into two parts: One is for an operating policy during flood period to consider water conservation and flood control, and the other is for flood time on a random water level at flood forecasting, This study is concerned with reservoir operation and discusses general reservoir operation at flood time. Flood control has problems such as the uncertainty of hydrologic models. technical limitations and some constraints. Therefore, we may prepare the quantitative flood control methods based on the assured flood control storage for reservoir operation. Transformed Reservoir Flood(TRF) Reservoir Operation Method(ROM) is a procedure which determines the adequate releases with considering dam safety for flood inflows over non-damaging discharge. Based on the TRF ROM which was explained in our published paper. the study discusses the TRF ROM with additional investigations and the general reservoir operation rules at flood time.

• Fire Science and Engineering
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• v.30 no.5
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• pp.54-59
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• 2016

Steel is a structural material that is inherently noncombustible. On the other hand, it has high thermal conductivity and the strength and stiffness of the material are reduced significantly when exposed to fire or high temperatures. Because the yield strength and modulus of elasticity of steel are reduced by 70% at $350^{\circ}C$ and less than 50% at $600^{\circ}C$, the load-carrying capacity of steel structure at high temperature rapidly lose. To be accepted as a fire-resisting construction, the fire test should be performed at the certificate authority. On the other hand, the fire test on a full-scale structure is limited by time, space, and high-cost. The analytical method was verified by a comparison with the fire test of H-section columns under compression and thermal analysis based on a finite element method using the ABAQUS program, and the numerical analysis method reported in this study was suggested as a complement of an actual fire test.