• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.539-543
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• 2008

이 연구에서는 보령화력발전소 방수로 수중방류구조에 대한 수리모형실험을 수행하여 수중방류구조 내 흐름 양상을 고찰하고, 수평 유공판의 거품저감 효과를 검토하였다. 수중방류구조 내 유속은 설계시 거품의 부상 및 외해 유출 방지를 위해 고려한 목표값 1 m/s 이내에 분포하였다. 또한, 2차 낙하 위치에 수평 유공판을 설치함에 따라 거품 발생량이 크게 감소함을 확인하였다. 그러나, 수평 유공판 설치에 따라서 평균유속은 거의 변화가 없었으며, 다만 외해 조위가 운전정지수위에 해당할 경우에는 수평 유공판 아래에서 연직방향 흐름의 세기가 감소하였다.

• Economic and Environmental Geology
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• v.46 no.2
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• pp.105-121
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• 2013

This study introduces integrated approach on detection of a leakage in a sea wall based on remote sensing, electric resistivity survey, electromagnetic survey, and borehole survey for the Seosan A-Region sea wall. The satellite temperature distribution from Landsat ETM+ data identifies water leakage distribution and period by analyzing temperature mixing patterns between sea water and fresh water. Electric resistivity survey provides both horizontal and vertical anomaly distributions over the sea wall showing below average electric resistivity. Electromagnetic survey(electrical conductivity survey) reveals the potential possible leakage areas with minimal background impact by comparing electrical conductivity values between high and low tides. Borehole image processing system confirmed the locations of anomalies identified from the other survey methods and distributions of vertical fracture zones. The integrated approach identified 41.7% of the sea wall being the most probable area vulnerable to water leakage and effectively approximated both horizontal and vertical distribution of water leakage. The integrated analysis of remote sensing, electric resistivity survey, electromagnetic survey and borehole survey is considered to be an optimal method in identifying water leakage distribution, period, and extent of fractures knowledged from the boreholes.

• Journal of the Korean Geographical Society
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• v.39 no.4
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• pp.528-543
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• 2004

The biogeographical approach on the species composition, distributional range, and life form of native Korean conifers suggests that the Korean Peninsula harbors 4 families 10 genera 30 species. Early-evolved conifers maintain high species diversity and broad distribution. During the glacial periods, the ranges of cold-tolerant conifers expanded, on the other hand, those of warmth-tolerant ones reduced. Presence of endemic subalpine conifers might be the result of long-term isolation of conifers on high mountains. Horizontal and vertical ranges of native Korean conifers are classified into alpine, subalpine, montane, coastal, insular and disjunctive types, and then subdivided into twelve sub-types. Typical life form of native Korean conifers is evergreen tree, blooms in spring, and fruits ripe in autumn or following autumn. Oval and elliptical seeds with wing might be beneficial for their dispersal. Further works on the migration, dispersal, genetics, ecology of native Korean conifers are required for the better understanding of the biogeography of conifers.

• Nuclear Engineering and Technology
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• v.7 no.4
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• pp.277-284
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• 1975

A result of measurement for the relative dose distribution of neutron gamma mixed radiation field in the biological irradiation facility installed at TRIGA Mark-III reactor is described. The relative dose distributions of neutron-gamma mixed radiation field in the biological exposure room have been experimentally determined using a thermoluminescent dosimeter. Presented herein in graphical forms are the experimental results obtained. It as observed that the region commonly having the characteristics of rather homogeneous horizontal and lateral dose distributions is confined to the area bounded by the two planes horizontally parallel to the beam direction with heights of about 40 cm and 130 cm, respectively, at distances beyond 100 cm from the segmentary surface of the aluminum pool liner projected into the the exposure room, while other areas show a steeper gradient in dosage, especially the places adjacent to the segment of the aluminum pool liner and near the inner po${\gamma}$lion of the concrete walls of the exposure room.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.20 no.1
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• pp.62-72
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• 2008

In this study, an analytical model has been developed to predict the build-up of heat field due to a point heat source in the presence of sharp cross-flow depth change. The model has been applied to investigate the effect of the depth change and flow pattern on the heat field. Model results show that, when there is a sharp depth change in cross-flow direction, the heat transport across the boundary of the depth change is enhanced or diminished according to the increasing or decreasing of the horizontal diffusion flux. Including residual components as well as tidal currents give rise to reduce the effect of the horizontal diffusion on the heat transport because of increasing the advection of heat.

• Journal of the Korea Convergence Society
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• v.10 no.7
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• pp.47-54
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• 2019

The purpose of this study was to investigate the effect of visual conditions on the static balance of stable and unstable surfaces. Thirty healthy adults participated in this study (13 men, 17 women). Visual conditions were set as vertical, horizontal, and diagonal. It was performed on the pad to measure the balance on the unstable support surface. Using the balance measuring instrument, the General Stability Index, Weight Distribution Index, and Weight Distribution was measured. Paired t-tests were used for ground-based comparisons and one-way ANOVAs were used for comparisons within the same ground. The general stability index showed a significant difference according to the horizontal and vertical line directions on the stable support surface(p<.05). According to the comparison between the grounds, the weight distribution index on the unstable support surface showed a significant difference(p<.05). Weight distribution showed significant differences between the left and right eyes on the support surface with the stable and the unstable horizontal visual condition(p<.05). In static balance training, vertical and diagonal visual direction conditions are predicted to be helpful for training.

• The korean journal of orthodontics
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• v.27 no.5 s.64
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• pp.711-721
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• 1997

The purpose of this study was to investigate the stress distribution and intensity derived from the transpalatal lingual arch in the investing bone composed of photoelastic material(PL-3). The transpalatal lingual arch wire was deflected in the horizontal and vertical direction to give the various conditions. The two-dimensional photoelastic stress analysis was performed, and the stress distrebution was recored by photography The results were as follows: 1. In bilateral expansion, as horizontal deflection was singly applied, the stress was more concentrated on the root apex in square free end than round. In square free end, as vertical deflection was increased gradually, the black line meaning center of rotation moved inferiorly together with the increment of whole fringes. 2. In application of vertical deflection on anchorage side for unilateral expansion, the stress distribution that expansive force leaned to expansion side was observed. As vortical deflection increased, the extruding stress was observed on molar of expansion side. And as horizontal deflection increased, the tipping stress on the molar of anchorage side was observed. 3. In unilateral rotation with the asymmetric toe-in, the fringe appeared on the distal aspect of root apex.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.04a
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• pp.58-59
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• 2000

오존은 공간적.시간적 변동이 매우 큰 대기오염물질로 서울시의 27개 대기오염 자동측정망에서 실시간으로 측정.감시되고 있으며, 오존의 농도가 높아지는 여름철에는 오존경보제를 실시하고 있다. 특히 오존의 농도는 일사, 풍향, 풍속 등의 기상인자, $NO_x$, VOCs 등 전구물질의 농도, 그리고 지형에 따라서 영향을 받는 것으로 알려져 있다. 따라서, 본 연구에서는 서울지역에 대한 기하학적 축소모형을 제작하여 풍동내에서 풍향.풍속을 측정하여 지형에 따른 바람의 특성을 파악하였다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.73-74
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• 2001

도시지역의 오존농도는 배출원 환경 및 지형과 국지 기상조건에 의해 크게 영향을 받게 된다. 일반적으로 도시내 공단과 교통량이 많은 지역에서는 다량의 NO 배출에 의한 오존의 감소가 일어나는 반면 도시플륨의 풍하측의 지역에서는 오존의 축적과 함께 고농가 발생하게 된다 (Wang et al., 2001; Bower et al., 1994; Mckendry). 특히 연안도시의 경우 여름철 주로 발생하는 국지순환인 해풍에 의한 고농도를 경험하게 되는데, 이는 수면의 낮은 오존침적으로 인해 소멸의 영향이 적고 (Entwistle, 1997), 해풍역전으로 인한 연직혼합의 제한으로 인해 발생한다고 볼 수 있다 (Lu and Turco, 1994). (중략)

• Journal of the Korean Geosynthetics Society
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• v.22 no.2
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• pp.85-92
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• 2023

This paper describes the comparative results of measured and predicted values for the horizontal displacement of earth retaining wall based on two field cases, in order to evaluate the application of lateral earth pressure to earth retaining wall supported by earth anchor in Jeju. The prediction of lateral earth pressure acting on the earth retaining wall was performed by elasto-plastic analysis using Rankine earth pressure, Hong & Yun lateral earth pressure, Terzaghi & Peck modified lateral earth pressure, and Tschebotarioff lateral earth pressure. As a result, the predicted value of the maximum horizontal displacement for site A was about 10 to 12 times greater than the measured value, and in the case of site B, the predicted value was evaluated as about 9 to 12 times greater than the measured value. That is, both sites showed a similar increase rate in the maximum horizontal displacement by the predicted value compared to the measured value. In all field construction cases, the maximum horizontal displacement by measured values occurred in the sedimentary layer, soft rock layer, and clinker layer, and the horizontal displacement distribution was shown in a trapezoidal shape. The maximum horizontal displacement by the predicted value occurred around the clinker layer, and the horizontal displacement distribution was elliptical. In the ground with a clinker layer, the measured value showed a very different horizontal displacement tendency from the predicted value, because the clinker layer exists in the form of a rock layer and continuous layer. In other words, it is unreasonable to apply the existing prediction method, which is overestimated, because the characteristics of the earth pressure distribution in Jeju show a tendency to be quite different from the predicted earth pressure distribution. Therefore, it is necessary to conduct a research on the lateral earth pressure in the realistic Jeju that can secure more economic efficiency.