수치모형을 이용한 사방댐 설치위치에 따른 토석류 저감량 분석

Won Jun Tak,Kye W on Jun,Byung Sik Kim,Yong Ho Yoon 위기관리 이론과 실천 2017 Crisisonomy Vol.13 No.4

최근 국내에서는 이상기온으로 인한 국지성 폭우와 여름철 태풍 및 집중호우로 인한 다양한 재해가 발생되고 있으며 재해유형중에서도 산지재해에 속하는 토석류가 급증하고 있다. 토석류는 산지에서 일어나는 것으로 한정하기 쉬우나, 도심과 인접한 산지지역에서 토석류가 발생하여 도심지 및 고속 도로, 교량 등에 큰 피해를 불러오기도 한다. 이처럼 토석류는 산지와 도심지 모두 발생 위험성이 높고 피해범위 또한 예측이 쉽지 않아 토석류에 대해 여러분야로 연구가 이루어지고 있다. 이 중에 서도 토석류를 제어하는 가장 효과적인 구조물로 토석류 유출방지시설에 대한 연구가 많이 이루어 지고 있지만 토석류가 발생하거나 또는 토석류 위험지역의 유역특성이나 현장여건을 적용한 토석류 유출저감시설의 위치에 대한 연구는 미비한 상태이다. 따라서, 본 연구에서는 토석류 수치모형을 이용하여 토석류 발생시 이동 메커니즘과 토석류 유출방지시설의 위치별 저감효과를 분석하였다. Recently, South Korea has been facing a range of disasters caused by localized heavy rainfalls, tropical typhoon, and torrential downpours. In particular, debris flows disasters usually occurring in the mountains have rapidly increased during the past few years. However, debris flows are also observed in mountainous areas near cities, bringing significant damages to city centers, highways, bridges, etc. Thereby, debris flows can lead to high risk in both mountainous areas and city centers. In addition, difficulties in debris-flow forecasting increase the need for numerical studies on debris flows. Although various researches have widely been conducted on run-off control facilities for debris flows, it is necessary to focus more on research that would identify an ideal location for debris flow runoff reduction facilities based on basin characteristics or site conditions for the debris flow areas. In this regard, this research used a debris flow numerical model to identify the transfer mechanism of debris flows and analyzed the debris flow reduction effect of runoff control facilities by the installation location.

지역사회복지협의체 종사자의 특성이 통합서비스에 미치는 영향에 관한 연구: 민간인과 공무원 비교를 중심으로

최종복 ( Choi Jong-bog ),김석준 ( Kim Seok-jun ),이경온 ( Lee Kyeong-on ) 한국보건사회연구원 2012 保健社會硏究 Vol.32 No.2

본 연구는 지역사회복지협의체의 발전적인 성과를 강화하기 위한 방법으로 그간 연구되지 않은 지역사회복지협의체 종사자(간사)의 특성이 통합서비스에 어떠한 영향을 미치는지 민간인 종사자와 담당 공무원을 비교하여 분석하였다. 지역사회복지협의체의 궁극적인 목적은 통합서비스의 제공에 있다고 할 수 있는데, 이를 효과적으로 분석하기 위해 다섯 가지 하위요인(자원개발, 자원관리, 네트워크, 민 ? 관 협력, 서비스 조정)으로 세분화하였고 종사자의 특성은 개인적 특성(성별, 연령, 학력, 혼인여부)과 환경적 특성 (근무경력, 근무형태, 자격, 업무기간, 협의체 전담여부, 타 업무 병행 시간, 주당 근무 시간, 교육 횟수, 협의체 회의개최 횟수, 실무분과 회의개최 횟수, 자체예산 사업 수, 외부지원 사업 수, 자원개발 및 연계 경험 등)으로 나누어 살펴보았다. 연구결과, 지역사회복지협의체 종사자의 근무형태, 업무담당기간, 자체예산 사업수, 교육 횟수와 근무경력, 실무분과 회의개최 횟수, 협의체 회의개최 횟수, 외부지원 사업 수 등이 통합서비스 에 유의한 영향을 미치고 있음을 알 수 있었다. 이러한 결과를 토대로 할 때 지방자치 단체에서는 자체예산 사업수를 늘리는 등 행 ? 재정적인 지원을 강화하여야 할 것이다. 또한 종사자의 상황에 따라서는 민간인 종사자의 경우 안정적인 근무환경 지원체계를 마련하고, 공무원 종사자의 경우에는 업무적 이해를 높이기 위한 직무교육과 민간 실무 분과와의 유기적인 연계활동 등이 적극 장려되어야 한다. This study is essentially a method proposed to enhance the developmental performance of the community social welfare consultative groups, analysing the influence of various traits of social welfare consultative group workers, a topic that has not yet been a subject of study, which have not been a topic for studies in the past, on integrated services, the purpose of consultative groups, through a comparison between civilian workers and government officials. In order to conduct the analysis effectively and efficiently, five sub-factors have been identified, while the traits of group workers have been classified into personal characteristics and environmental characteristics As a result, it was observed that job types, work periods, number of internally-financed projects, frequency of training sessions and work experience, frequency of working-level branch meetings, frequency of consultative group meetings, number of externally-financed projects have significant influence on the integrated service. Based on this result, local governments should reinforce their administrative and financial support; as for the situation of workers, stable working environment supporting system should be prepared for civilian workers and for government officials, there should be job training programs to increase vocational understanding and networking to encourage organic activities with working-level branch.

Development of FEP & Scenario Integrated Information Processing Platform for Long-Term Evolution of Spent Fuel Disposal System

Sang hun Jeon,Sunggyun Jang,Jeong Hyun Lee,Jun Ki An,Jin Ryu,Si On Kim,Won-Seok Kim 한국방사성폐기물학회 2022 한국방사성폐기물학회 학술논문요약집 Vol.20 No.2

CYPRUS is a web-based waste disposal research comprehensive information management program developed by the Korea Atomic Energy Research Institute over three years from 2004. This program is stored as existing quality assurance documents and data, and the research results can be viewed at any time. In addition, it helps to perform all series of tasks related to the safety evaluation study of the repository in accordance with the quality assurance system. In the future, it is necessary to improve the user convenience by clarifying the relationship between FEP and scenarios and upgrading output functions such as visualization and automatic report generation. This purpose of this study is to research and develop the advanced program of CYPRUS. This study is based on building FEP, DIM and scenario databases. It is necessary to develop an algorithm to analyze and visualize the FEP, DIM and scenario relationship. This project is an integrated information processing platform for DB management and visualization considering user convenience. The first development goal is to build long-term evolutionary FEP, DIM, and scenarios as a database. The linkage by FEP item was designed in consideration of convenience by using a mixed delimiter of letters and numbers. This design provides information on detailed interactions and impacts between FEP items. Scenario data lists a series of events and characteristic change information for performance evaluation in chronological order. In addition, it includes information on FEP occurrence and mutual nutrition by period, and information on whether or not the repository performance is satisfied by item. The second development goal is to realize the relationship analysis and visualization function of FEP and scenario based on network analysis technique. Based on DIM, this function analyzes and visualizes interactions between FEPs in the same way as PID, RES, etc. In addition, this function analyzes FEP and DIM using network analysis technique and visualizes it as a diagram. The developed platform will be used to construct and visualize the FEP DB covering research results in various disposal research fields, to analyze and visualize the relationship between core FEP and scenarios, and finally to construct scenarios and calculation cases that are the evaluation target of the comprehensive performance evaluation model. In addition, it is expected to support the knowledge exchange of experts based on the FEP and scenario integrated information processing platform, and to utilize the platform itself as a part of the knowledge transfer system for knowledge preservation.

Dynamic characteristics of composite tilting pad journal bearing for turbine/generator applications

On, Seung Yoon,Kim, Yun Seong,You, Jun Il,Lim, Jun Woo,Kim, Seong Su Elsevier 2018 Composite structures Vol.201 No.-

<P><B>Abstract</B></P> <P>Tilting pad journal bearings have been employed for turbine, compressor, pump, and generator applications owing to their high loading capacity, excellent stability, and service durability at high operation speed compared to conventional journal bearings. For high-speed and high-performance applications, tilting pad journal bearings should reduce the rotor vibration. Therefore, the bearings are designed to have excellent damping characteristics. In this study, composite tilting pad journal bearings consisting of carbon fiber/epoxy composites and a backup metal are fabricated to increase the dynamic performance and durability. A modal analysis is performed to investigate dynamic stability of the composite tilting pad. Moreover, the damping coefficient of fluid film, oil film pressure, and orbit of rotor are calculated with respect to the liner materials under a hydrodynamic lubrication state. To verify the analysis results, hydrodynamic lubrication tests of composite and white metal tilting pad journal bearings are conducted using an industrial test bench. As a result, the composite tilting pad journal bearing has effectively reduced the rotor vibration and increased the stability and durability of the bearing system compared to the white metal tilting pad journal bearing.</P>

Origin of Electrical Instabilities in Self-Aligned Amorphous In–Ga–Zn–O Thin-Film Transistors

On, Nuri,Kang, Youngho,Song, Aeran,Ahn, Byung Du,Kim, Hye Dong,Lim, Jun Hyung,Chung, Kwun-Bum,Han, Seungwu,Jeong, Jae Kyeong Institute of Electrical and Electronics Engineers 2017 IEEE transactions on electron devices Vol.64 No.12

<P>This paper examined the performance and bias stability of amorphous In–Ga–Zn–O ( <TEX>${a}$</TEX>-IGZO) thin-film transistors (TFTs) with a self-aligned coplanar structure. The activation energy barrier responsible for the positive bias thermal stress (PBTS)-induced instability of the <TEX>${a}$</TEX>-IGZO TFTs with low oxygen loadings can be attributed to the migration of cation interstitial defects. However, the IGZO TFTs with high oxygen loadings could not be explained by the existing defect model. The first-principle calculation indicates that the cation vacancy, such as <TEX>${V}_{\textsf {In}}$</TEX>, with the hydrogen incorporation plays an important role in determining the PBTS-dependent degradation of the threshold voltage.</P>

Exploring Implementation of Multicultural Mathematics Education in Northern Thai Classrooms

Jun-on, Nipa,Kim, Rae Young(김래영) 학습자중심교과교육학회 2019 학습자중심교과교육연구 Vol.19 No.21

본 연구는 태국의 특수한 문화적, 사회적 맥락 속에서 이루어지고 있는 다문화 교육과정과 수학 교육 실행을 하나의 사례로서 분석하여 다문화 수학교육 정책과 수행에 대한 의미 있는 시사점을 제공하고자 한다. 이를 위해 태국 북부의 “고산족 (Hilltribes)”이 살고 있는 3개 주의 9명의 수학 교사들의 수업을 관찰하고 교사와의 인터뷰, 수업지도안,학생들의 산출물 등을 수집하여 선행연구 고찰로부터 구성한 분석틀로 범주별 의미 중심의 분석적 코딩을 통해 질적 분석을 실시하였다. 연구 결과, 연구에 참여한 수학교사들은 다문화 교실임에도 불구하고 학생들의 인종적, 문화적 다양성을 인식하지 못하고 제 대로 된 다문화 수학 교육을 시행하지 않고 있었다. 이에 대한 세 가지 이유로 먼저, 교사들은 소수 민족 학생들에게 낮은 기대를 갖고 있었다. 또한 언어적 문제로 인해 교사들은 소수 민족학생들의 학습 과정과 결과를 제대로 해석하지 못하고 있었다. 마지막으로 교사들은 학생들의 다양성을 강조하지 않는 국가 정책과 표준에만 의존한 나머지 모든 수업을 국가 교육과정에 맞게 “Thai-ness”를 강조한 수업을 수행하고 있었다. 본 연구의 결과를 통해 다문화 수학 교육에 대한 인식의 출발점을 위한 제안을 제시하고자 한다. In Northern Thailand, the settlement of ethnic minority groups, called by the nation as “Hilltribes”, has led to the diverse classrooms. Apart from examination of multicultural education that failed to reflect classrooms with students from ethnic minority groups, this study aims to examine multicultural mathematics education in Northern Thai mathematics classrooms using a developed research analytic framework. Qualitative data regarding the implementation of multicultural mathematics education were collected from nine mathematics teachers in three provinces of northern Thailand through the interview, artifacts, and observation, and analyzed by analytic coding method under the categories of the research analytic framework. The main result of this case study indicated that the participated teachers do not manifest multicultural mathematics education in their classrooms. This study found that it resulted from the teachers’ unawareness of its necessity due to three reasons. Firstly, the teachers gave their low expectations for students from ethnic minority groups. Moreover, the teachers misinterpreted students’ performance because of the language obstacle. Finally, the teachers simplified their teaching by relying only on national plans and standards that do not emphasize students’ ethnic diversity. The suggestions to initiate the awareness of multicultural mathematics education are also provided in this study.

감마線分光分析 및 熱螢光檢出法에 의한 自然放射線의 線量測定硏究

田載植,吳熙弼,崔哲圭,吳憲鎭,河正雨 충남대학교 기초과학연구소 1986 연구논문집 Vol.6 No.-

감마선분광분석 및 열형광선량측정법에 의한 자연환경방사선의 선량해석에 관한 연구를 1984년 10월부터 약 1년간에 걸쳐 충남대학교 대덕캠퍼스내의 1만㎡ 규모의 평면개활지에서 수행하였다. 이 연구에서 사용한 검출기는 3″ø×3″NaI(TI) 閃光計數器와 plastic에 밀봉하여 금속판에 압착 처리한 chip과 Teflon-disk 로된 2종의 LiF TLD였다. 실측실험으로는 3회에 걸친 24시간 cycle의 in-situ spectrometry와 2회의 3개월 cycle과 1회의 1개월 cycle에 걸친 TLD field dosimetry를 수행하였다. 측정한 모든 spectrum은 G(E)연산자법에 의하여 照射線量率로 환산하였고 그 결과로부터 환경방사선의 地殼成分을 산출하였다. 結果에 의하면 spectrometry로 구한 조사선량율이 평균(10.54±2.96)μR/hr, TLD chip으로 측정해석한 값은 (12.0±3.4)μR/hr, disk에서 얻은 값이 (11.0±3.6)μR/hr로 오차범위 안에서 매우 좋은 일치를 보이고 있다. 그러나 감마선분광분석에 의한 자연방사선의 日變化에는 가끔 심한동요가 관측되었다. 정확한 환경방사선량해석을 위하여 감마선분광분석과 TLD의 적절한 동시 배합사용이 바람직 하며, 보다 고감도의 TLD에 관한 연구와 국제비교등을 통한 선량평가의 精度向上을 위한 보다 깊이있는 연구가 필요하다는 結論에 도달하였다. A study for the assessment of natural environmental radiation exposure at a flat and open field of about 10,000㎡ in area in CNU Daeduk campus has been carried out by means of gamma-ray scintillation spectrometry and thermoluminescence dosimetry for one year period of time from October 1984. The detectors used were 3″ø×3″NaI(TI) and two different types of LiF TLD, namely, chip sealed in plastic sheet which tightly pressed on two open holes of a metal plate and Teflon disk. Three 24-hour cycles of in-situ spectrometry, and two 3-month and one 1-month cycles of field TL dosimetry were performed. All the spectra measured were converted into exposure rate by means of G(E) opertaion, and therefrom exposure rate due to terrestrial component of environmental radiation was figured out. Exposure rate determined by the spectrometry was, on average, (10.54±2.96)μR/hr, and the rates of (12.0±3.4)μR/hr and (11.0±3.6)μR/hr were obtained from chip and disk TLD, respectively. Fluctuations in diurnal variation of the exposure rate measured by the spectrometry were noticeable sometime even in a single cycle of 24 hours. It is concluded that appropriately combined use of TLD with iu-sitn gamma-ray spectrometry system can give more accurate and precise measure of environmental radiation exposure, and further study for more adequate and sensitive TLD for environmental dosimetry, including improvement and elevation of accuracy in data assessment through inter-laboratory or international intercomparison is necessary.

A NOTE ON DISCRETE SPACES

Seung On Lee, Young Jin Pi, Sung Jun Yoem 충북대학교 금융수학연구소 2013 금융수학연구소학술지 Vol.8 No.-

In this note, we deal with discrete spaces and uniform convergence on metric spaces. At rst we dene some metrics which induce discrete topology on a nonempty set X, then study the completeness of discrete spaces and investigate the uniform continuity between discrete spaces.

ISO/TC108/SC1

전오성(On Sung Jun),최상규(Sang-Kyu Choi),김민호(Min Ho Kim) 한국소음진동공학회 1998 한국소음진동공학회 학술대회논문집 Vol.1998 No.6

Impacts of spectral nudging on the simulated surface air temperature in summer compared with the selection of shortwave radiation and land surface model physics parameterization in a high-resolution regional atmospheric model

Park, Jun,Hwang, Seung-On Pergamon 2017 Journal of Atmospheric and Solar-Terrestrial Physi Vol.164 No.-

<P><B>Abstract</B></P> <P>The impact of a spectral nudging technique for the dynamical downscaling of the summer surface air temperature in a high-resolution regional atmospheric model is assessed. The performance of this technique is measured by comparing 16 analysis-driven simulation sets of physical parameterization combinations of two shortwave radiation and four land surface model schemes of the model, which are known to be crucial for the simulation of the surface air temperature. It is found that the application of spectral nudging to the outermost domain has a greater impact on the regional climate than any combination of shortwave radiation and land surface model physics schemes. The optimal choice of two model physics parameterizations is helpful for obtaining more realistic spatiotemporal distributions of land surface variables such as the surface air temperature, precipitation, and surface fluxes. However, employing spectral nudging adds more value to the results; the improvement is greater than using sophisticated shortwave radiation and land surface model physical parameterizations. This result indicates that spectral nudging applied to the outermost domain provides a more accurate lateral boundary condition to the innermost domain when forced by analysis data by securing the consistency with large-scale forcing over a regional domain. This consequently indirectly helps two physical parameterizations to produce small-scale features closer to the observed values, leading to a better representation of the surface air temperature in a high-resolution downscaled climate.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The impact of spectral nudging is assessed with a regional numerical model. </LI> <LI> The simulated summer surface air temperature is quite reasonable. </LI> <LI> Spectral nudging improves the analysis-driven simulation results significantly. </LI> <LI> The impact of physic parameterizations is not as influential as spectral nudging. </LI> <LI> Large-scale forcing is still crucial for dynamical downscaling. </LI> </UL> </P>