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The Impact of Mergers on the Experiences of Students (대학 통폐합에 대한 학생들의 적응과정 연구)

  • Chae, Jae-Eun
    • Korean Journal of Comparative Education
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    • v.23 no.5
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    • pp.53-75
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    • 2013
  • This article explores the impact of mergers on the experiences of students. A case design is used to gain an in-depth understanding of the students in a Korean university that was combined with a two-year college in 2007. Semi-structured interviews of 11 direct entrants, 5 transfer students, and 7 professors were conducted in 2010 for the data collection. The results suggest that mergers do not necessarily ensure the integration of the students involved. Since mergers pose enormous challenges to both transfer students and direct entrants, university leaders need to give careful attention to students' persistence and integration as the campus changes. The results also reveal that students' experience of mergers may be affected by cultural backgrounds as well as the hierarchical structure of higher education. In Korean society, where credentialism prevails, mergers can have different impacts on students who come from initial institutions of differing perceived quality, and thus mergers may incite tension among the students. In light of these concerns, this study's findings highlight the importance of student integration as a key element in mergers.

A study on alluvial deposits of tributaries of Yungsan river, near Damyang. (담양지역 영산강 지류 하천 퇴적층의 특성에 대한 연구)

  • Kim, Jong Yeon;Hong, Se Sun
    • Journal of The Geomorphological Association of Korea
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    • v.20 no.4
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    • pp.51-70
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    • 2013
  • The characteristics of deposits formed by the Daejon-cheon and Soobuk-cheon, dissecting the mountains such as Byungpung Mt. and Samin Mt. in western part of Damyang county, Jeonmam province. Results from field survey and bore hole logging by KIGAM are used in interpreting depositional environment, in this study. By the result of deposits near of the channels Daejon-cheon and Soobuk-cheon, and main channel of Youngsan River, the depth of sediment layers in this area is 4~7m, far thinner than formerly estimated. Weathered material of local rocks forms the base of the sedimentary layers. It can be assumed that the location channel of the Youngsan river has been stable ever since the start of the sedimentary events. Sediment particles of tributaries are angular than those of Youngsan River. Particles are larger and sorting is poor. It is interpreted as mount flash flood deposits. Main sources of sediments at the valley bottom or deposition dominated area are the terrace deposits or slope deposits over the gentle foot-slope or front of surrounding mountains. Some particles show polygonal cracking on the surface originated from the strong chemical weathering, while most of these has high angularity. It means various geomorphic processes operate to produce and transport the particles in this area.Isolated hills within the sedimentary plains are made with weathered materials of local bedrock. In the case of foot-slope of the hills, thin sedimentary layers are found. So it can be concluded that surface features of deposition zone of the Daejon-cheon and Soobuk-cheon is formed by the filling of lower part of the valley and its feature partly controlled by the relief of the weathering front.

A Study on Drop Shaft Bottom of Maximum Pressure of the Deep Tunnel by Stilling Basin of Depth (대심도 터널의 수직 유입구 감세지 깊이에 따른 바닥면 최대압력 비교 연구)

  • OH, Jun Oh;Park, Jae Hyeon;Park, Chang Keun
    • Proceedings of the Korea Water Resources Association Conference
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    • 2015.05a
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    • pp.74-74
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    • 2015
  • 최근 홍수의 특성과 피해 양상은 과거와는 다르게 변화하고 있으며, 급격한 도시화로 인하여 기존 하천유역의 저류 능력이 감소하였으며 이러한 한계를 극복하기 위하여 이미 외국에서는 대심도 터널을 활용한 홍수재해 관리방안이 오래전부터 활용되어 왔다. 본 연구에서는 대심도 터널의 유입구, 수직갱, 감세지, 배수터널과 같은 시설물 중 대심도 터널 설계 시 수직 유입구를 통해 유입되는 유량의 에너지를 완화하고 효과적으로 배수 할 수 있도록 중요한 역할을 하는 감세지의 효율적인 깊이 산정을 위하여 수리모형실험을 실시하였으며, 모형은 Froude 상사법칙을 사용하여 원형의 1/18크기로 제작하였다. 본 연구에서 실시한 감세지 모형의 깊이는 0.278 m(원형 5.0 m), 0.417 m(원형 7.5 m)이며, 각 감세지 깊이별 수직 유입구 3개소(저지수직구1, 저지수직구2, 고지수직구) 및 5가지의 유량 CASE에 대하여 감세지 바닥면 압력을 비교?분석 하였다. 수직 유입구 3개소의 설계조건에 따른 감세지 깊이별 바닥면 압력 분포 평가를 실시한 결과 저지수직구1의 감세지 깊이 0.278 m(원형 5.0m)에서는 최대 압력이 4번 지점에서 $0.075kg/cm^2$(원형 1.30 MPa)이 측정 되었으며, 0.417 m(원형 7.5m)에서는 최대 압력이 1번지점에서 $0.089kg/cm^2$(원형 1.54MPa)이 측정되었다. 또한 저지수직구2의 감세지 깊이 0.278 m(원형 5.0 m)에서는 최대 압력이 1번 지점에서 $0.074kg/cm^2$(원형 1.28 MPa)이 측정 되었으며, 0.417 m(원형 7.5 m)에서는 최대 압력이 2번지점에서 $0.088kg/cm^2$(원형 1.52 MPa)이 측정되었다. 고지수직구의 감세지 깊이 0.278 m(원형 5.0 m)에서는 최대 압력이 3번 지점에서 $0.082kg/cm^2$(원형 1.42 MPa)이 측정 되었으며, 0.417 m(원형 7.5 m)에서는 최대 압력이 1번지점에서 $0.092kg/cm^2$(원형 1.59 MPa)이 측정되었다. 본 연구에서 실시한 수리모형실험의 결과 저유량에서 고유량으로 갈수록 최대압력지점은 반시계방향으로 움직이는 것을 알 수 있으며, 이는 수직 유입구의 설계조건에 따른 수직갱에서의 회전수차에 의하여 발생하는 것으로 분석하였다. 따라서 적절한 감세지 깊이 산정을 위해서 대심도터널의 수직 유입구(유입구형태, 수직갱)의 평가가 함께 유기적으로 이루어져야 할 것으로 판단된다.

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Study of seismic performance of super long-span partially earth-anchored cable-stayed bridges

  • Zhang, Xin-Jun;Yu, Cong;Zhao, Jun-Jie
    • Structural Engineering and Mechanics
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    • v.72 no.1
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    • pp.99-111
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    • 2019
  • To investigate the seismic performance of long-span partially earth-anchored cable-stayed bridge, a super long-span partially earth-anchored cable-stayed bridge scheme with main span of 1400m is taken as example, structural response of the bridge under E1 seismic action is investigated numerically by the multimode seismic response spectrum and time-history analysis, seismic behavior and also the effect of structural geometric nonlinearity on the seismic responses of super long-span partially earth-anchored cable-stayed bridges are revealed. The seismic responses are also compared to those of a fully self-anchored cable-stayed bridge with the same main span. The effects of structural parameters including the earth-anchored girder length, the girder width, the girder depth, the tower height to span ratio, the inclination of earth-anchored cables, the installation of auxiliary piers in the side spans and the connection between tower and girder on the seismic responses of partially ground-anchored cable-stayed bridges are investigated, and their reasonable values are also discussed in combination with static performance and structural stability. The results show that the horizontal seismic excitation produces significant seismic responses of the girder and tower, the seismic responses of the towers are greater than those of the girder, and thus the tower becomes the key structural member of seismic design, and more attentions should be paid to seismic design of these sections including the tower bottom, the tower and girder at the junction of tower and girder, the girder at the auxiliary piers in side spans; structural geometric nonlinearity has significant influence on the seismic responses of the bridge, and thus the nonlinear time history analysis is proposed to predict the seismic responses of super long-span partially earth-anchored cable-stayed bridges; as compared to the fully self-anchored cable-stayed bridge with the same main span, several stay cables in the side spans are changed to be earth-anchored, structural stiffness and natural frequency are both increased, the seismic responses of the towers and the longitudinal displacement of the girder are significantly reduced, structural seismic performance is improved, and therefore the partially earth-anchored cable-stayed bridge provides an ideal structural solution for super long-span cable-stayed bridges with kilometer-scale main span; under the case that the ratio of earth-anchored girder length to span is about 0.3, the wider and higher girder is employed, the tower height-to-span ratio is about 0.2, the larger inclination is set for the earth-anchored cables, 1 to 2 auxiliary piers are installed in each of the side spans and the fully floating system is employed, better overall structural performance is achieved for long-span partially earth-anchored cable-stayed bridges.

A Study on the Evaluation Index of Crown Height given Marine Environmental Factors and Ship Characteristics (해상 환경 및 선박 특성을 반영한 마루높이 평가지표에 관한 연구)

  • Kim, Seungyeon
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.24 no.4
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    • pp.438-444
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    • 2018
  • Korea has recently selected twenty-two ports for reinforcement breakwater installation of protection facilities, due to rise sea level caused by global warming and increase in the number of typhoon and tsunami. In addition, due to consistent enlargement of ship size, dredging for depth of water for large vessel's berthing and enlargement of berth is under construction. However, no definite construction plan for the reinforcement and lengthening of crown height, which has close relationship with the safe mooring of ships. In this study, domestic and foreign design criteria of crown height were analyzed, and the crown height evaluation index and evaluation method were developed by dividing it into environment and ship elements. In particular, in the case of ship evaluation index, each step was set up in 4 steps according to domestic and foreign regulations, weighted by each step, and the safety level of crown height was evaluated. As a result of the mooring safety simulation of the 100,000 ton cruise ship, the appropriate minimum crown height standard was derived to be 3 m above A.H.H.W. The results of this study are expected to be used as basic data to propose the crown height standard reflecting ship characteristics.

Water Depth and Riverbed Surveying Using Airborne Bathymetric LiDAR System - A Case Study at the Gokgyo River (항공수심라이다를 활용한 하천 수심 및 하상 측량에 관한 연구 - 곡교천 사례를 중심으로)

  • Lee, Jae Bin;Kim, Hye Jin;Kim, Jae Hak;Wie, Gwang Jae
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.39 no.4
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    • pp.235-243
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    • 2021
  • River surveying is conducted to acquire basic geographic data for river master plans and various river maintenance, and it is also used to predict changes after river maintenance construction. ABL (Airborne Bathymetric LiDAR) system is a cutting-edge surveying technology that can simultaneously observe the water surface and river bed using a green laser, and has many advantages in river surveying. In order to use the ABL data for river surveying, it is prerequisite step to segment and extract the water surface and river bed points from the original point cloud data. In this study, point cloud segmentation was performed by applying the ground filtering technique, ATIN (Adaptive Triangular Irregular Network) to the ABL data and then, the water surface and riverbed point clouds were extracted sequentially. In the Gokgyocheon river area, Chungcheongnam-do, the experiment was conducted with the dataset obtained using the Leica Chiroptera 4X sensor. As a result of the study, the overall classification accuracy for the water surface and riverbed was 88.8%, and the Kappa coefficient was 0.825, confirming that the ABL data can be effectively used for river surveying.

Regional Quality of Life Satisfaction and Life SOC Service Gap Analysis: A Case of Chungcheongnam-do (지역의 삶의 질 만족도와 생활SOC 서비스 격차분석: 충청남도를 사례로)

  • Hong, Sung-Hyo;Im, Jun-Hong;Lee, Gyounju
    • Land and Housing Review
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    • v.12 no.4
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    • pp.61-79
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    • 2021
  • Despite the rapid economic growth, people's quality of life has not been improved and the regional and hierarchical disparities of it have deepened. We analysed regional differences in quality of life and it was found that non-capital regions, provinces and rural areas compared to Seoul and capital region, metropolitan cities, and urban areas respectively, show a relatively lower level of satisfaction in the quality of life. An in-depth analysis of Chungcheongnam-do province shows that the trend was similar to that of the national analysis. The quality of life satisfaction of the elderly was lower than that of the young and middle-aged, and this trend was similar regardless of region. Young people living in the Dong area showed high satisfaction with the quality of life than the middle-aged and elderly living in the Myeon area. It was observed the level of Life SOC services in urban areas have been better than the one in rural areas. However, there is no clear relationship between quality of life satisfaction and the expansion of Life SOC, therefore, it is difficult to argue that the government intervention to expand Life SOC will improve the citizen's quality of life satisfaction. The implication of the study is that the future supply policy of the Life SOC should be based on the detailed analysis of the impact on the environment, and linking with the development of various programs in progress rather than supplying a Life SOC that provides a single service. Furthermore, in rural areas it is essential to enhance user demand by combining several services in supply and to improve the efficiency of managing the services.

An Analysis of School and Work Activity Systems Affecting the Learning and Transfer of Graduate School Student-Workers (대학원에 재학하는 직장인의 학습과 전이에 영향을 미치는 학교와 일터활동 분석)

  • Kim, Ji-Young;Chang, Won-Sup
    • Journal of vocational education research
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    • v.37 no.2
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    • pp.167-190
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    • 2018
  • This study examines based on Cultural-Historical Activity Theory, graduate school student-workers' learning and developmental transfer in school and work. For this purpose, a question is raised. how do components of activities in school and workplace impact on learning and developmental transfer? For this study, based on the results of In-depth interview, questionnaire was designed and quantitative research has been conducted. This study analyzed 288 graduate school student-workers. As a results, First, the components which have an effect on learning were analyzed and the results show that among the components of the school activity system, the competitiveness reinforcement from object, the role of academic major from division of labor, and the interaction with professors from community are significant variables. Second, in case of developmental transfer, the activeness of class participation from tool, the role of academic major from division of labor, and the interaction with professors from community are significant variables of the school activity system and the self realization from object, the role in the workplace from division of labor, the interaction with supervisors from community, and the systemization of work from rule are significant variables of workplace activity system. On the basis of the findings, implications of the study and suggestions for further research are discussed.

Material Characteristics and Nondestructive Deterioration Assessment for the Celestial Chart Stone, Korea (천상열차분야지도 각석의 재질특성과 비파괴 훼손도 평가)

  • Yoo, Ji Hyun;Lee, Myeong Seong;Choie, Myoungju;Ahn, Yu Bin;Kim, Yuri
    • The Journal of the Petrological Society of Korea
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    • v.27 no.4
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    • pp.207-222
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    • 2018
  • Celestial Chart Stones (original and reproduction) in the National Palace Museum are representative scientific cultural heritage of Korea. Material analysis and nondestructive deterioration assessment were conducted for long-term preservation of these stones. Material analysis revealed that the original was composed of slate and the reproduction was made of dolostone. The original consists of quartz, mica, dolomite minerals, while the reproduction was made up of dolomite, calcite and forsterite. Major deterioration factors of the original stone were cracks and breakouts. In case of the reproduction, scratches and artificial materials were mainly observed. The green and black surface contaminants present at the sides and back of the two celestial chart stones were interpreted as resin-based paint materials. The physical property evaluation using ultrasonic velocity showed a low velocity in the upper left side of the original, while the front right side of the reproduction showed a weak property. Meanwhile, the To-Tc method using ultrasonic velocity was applied to major cracks that impede stability of the original. As a result, it has been calculated that the beginning and the center of the crack are the deepest.

Factors Affecting Job Satisfaction of Clinical Dental Hygienists (임상 치과위생사의 직무만족도에 영향을 미치는 요인)

  • Han, Ji-Hyoung;Song, Kwui-Sook;Shin, Sun-Jung
    • Journal of dental hygiene science
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    • v.18 no.6
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    • pp.374-379
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    • 2018
  • This study attempted to identify factors work environment that affect job satisfaction in dental hygienists. This study was conducted between August 29 and September 28, 2017, as part of an in-depth study of the 'Survey on the Working Environment of Clinical Dental Hygienists' of the Korean Dental Hygienists Association. To get the responses, the questionnaire was posted on the website of the Korean Dental Hygienists Association, and of the respondents, 4,663 were selected and analyzed. An independent t-test and one way ANOVA analysis were used to make a comparison of job satisfaction according to the general characteristics, salary, and tasks. Logistic regression analysis was conducted to identify factors affecting job satisfaction. The significance level was 0.05. In regard to salary information, the job satisfaction was found to be high (p<0.001) in cases where the salary was considered appropriate, when incentives were provided, when rewards or vacation expenses were supported, and when overtime and nightly work allowances were paid. In regard to job information, the job satisfaction was found to be high (p<0.001) when the volume of work was considered appropriate, when there were sufficient numbers in the workforce, and when the division of labor among the other personnel was clear. As a factor affecting job satisfaction of dental hygienists, the case of thinking that 'workload is appropriate' was found to be 2.052 times, showing the highest score. Job satisfaction in dental hygienists affects the turnover and has a significant effect on the performance of the organization. Therefore, it is believed, that it is urgent to improve the working environment such as salary and clear division of duties affecting job satisfaction of dental hygienists.