• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.186-188
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• 2003

Rail Route Alignment in hilly terrain is a difficult task to implement as several natural constraints poses threat to the safety and stability of the alignment. The conventional methods followed to find out the final location survey or the feasibility analysis for alignment is time taking consuming. Some times, due to inaccessibility of the terrain it becomes impossible to carry out such works. The construction works in hilly terrain, which are associated with the proposed alignment, are not same as carried out in plane areas due to a vast contrast between the two areas. Different geological structures such as faults, thrusts, synclines and anticlines are a big problem to carry out normal construction practices. Thus for a safe and stable railway route in the unstable hilly areas, it is required to carry out the feasibility analysis of the proposed alignment to assist the policy makers for a successful implementation of the alignment. In the present work Remote Sensing and GIS has been successfully used to carry out geological feasibility and slope stability analysis for rail route alignment work.

• 한국철도학회논문집
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• 제6권2호
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• pp.81-86
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• 2003

This study proposes the neural network simulator for the integrity evaluation of weld zone in railway rails. For these purposes, the ultrasonic signals for defects(crack) of weld zone in frames are acquired in the type of time series data and echo strength. The detection of the natural defects in railway truck is performed using the characteristics of echodynamic pattern in ultrasonic signal. And then their applications evaluated feature extraction based on the time-frequency-attractor domain(peak to peak, rise time, rise slope, fall time, fall slope, pulse duration, power spectrum, and bandwidth) and attractor characteristics (fractal dimension and attractor quadrant) etc. The constructed neural network simulator agrees fairly well with the measured results of test block(defect location, beam propagation distance, echo strength, etc). The Proposed neural network simulator in this study can be used for the integrity evaluation of weld zone in railway rails.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2001년도 가을 학술발표회 논문집
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• pp.501-508
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• 2001

Free vibration analysis of multi-delaminated composite beam-columns subjected to axial compression load is performed in the present study. In order to investigate the effects of multi-delaminations on the natural frequency and elastic buckling load of multi-delaminated beam-columns, the general kinematic continuity conditions are derived from the assumption of constant slope and curvature at the multi-delamination tip. Characteristic equation of multi-delaminated beam-column is obtained by dividing the global multi-delaminated beam-columns into segments and by imposing recurrence relation from the continuity conditions on each sub-beam-column. The natural frequency and elastic buckling load of multi-delaminated beam-columns according to the incremental load of axial compression, which is limited to the maximum elastic buckling load of sound laminated beam-column, are obtained. It is found that the sizes, locations and numbers of multi-delaminations have significant effect on natural frequency and elastic buckling load, especially the latter ones.

• 한국해양공학회지
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• 제2권1호
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• pp.163-169
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• 1988

A beach nourishment method can be used as one of the beach. The beach nourishment is affected br a natural condition and an artificial condition; a natural condtion include conditions of bottom slope, diameter of bottom materials and wave, and an artificial condition include deposit position, method, diameter and quantity of the nourishing sand. To obtain and the best diameter of the nourishing sand a two-dimensional hydraulic model test, which simulates the erosional beach, has been accmplished. In this study the protection of the beach erosion can be maximized when the nourishing sand of 0.84mm in diameter, which is about 2.5-3.5 times of the natural bottom materials in diameter.

• Animal Systematics, Evolution and Diversity
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• 제36권4호
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• pp.319-329
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• 2020

The sponge-dwelling shrimp, Anchistioides compressus Paulson, 1875, is recorded from Munseom Islet, Jejudo Island, Korea for the first time. All specimens were collected inside the orange coloured sponges by trimix diving at depth from 36-45 m on the rocky reef slope. Anchistioides compressus is characterized by the shape of the rostrum, the posterolateral teeth of the sixth somite, stylocerite being well developed, the anterior margin of the scaphocerite sharply produced, and the biunguiculate dactyli of the ambulatory pereiopods, as well as the proportions of the fingers of the second pereiopods. An illustrated description of the specimens and colour photo are provided to aid future recognition.

• 한국환경복원기술학회지
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• 제1권1호
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• pp.141-150
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• 1998

This study was conducted to find out the possibility of seeding of Zoysia japonica and woody plants for the revegetation of rock-exposed-cutslopes by Natural Topsoil Restoration Methods (NTRM). The 5cm thick layer of artificial soil was attached at rock-exposed cutslopes for the growth of Zoysia japonica and native woody plants by NTRM. The main results were summarized as follows. 1. Artificial soil attached at rock-exposed-slopes by NTRM was not eroded until recovered by Zoysia japonica and native woody plants. It shows extremely low soil erodibility. 2. One year later after seeding, woody plants show 100% ground coverage. But, in early stage, they grew more quickly at northwest slopes than at southeast slopes. 3. In seeding of Zoysia japonica, it grew more quickly at southeast slopes than at northwest slopes. Also, it grew better at lower part of the slopes than at middle part of the slopes. 4. After one year from seeding, the height of Lespedeza cyrtobotrya and Indigo/era pseudo-tinctoria were longer than any other plants. The next were Albizzia julibrissin, Lespedeza cuneata and wild flowers. The tree height of Rhus chinensis shows 28cm length, so it has enough possibility to be used for roadside revegetation works. 5. Lespedeza cyrtobotrya and Indigo/era pseudo-tinctoria show different importance values according to slope aspect. But, they show tendency to outweigh the other plants at all slope-aspects. 6. Most of the plants seeded by NTRM were germinated well and they covered rock-exposed-slopes so quickly and effectively. Thus it leads to conclusion that the revegetation methods used in this experiment was a very effective methods to recover rock-exposed-slopes by seeding of zoysia japonica and native woody plants.

• 식물분류학회지
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• 제38권4호
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• pp.573-582
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• 2008

충북 영동군 설계리 인근의 산지에서 새롭게 밝혀진 한국특산속 식물인 미선나무의 자생지를 조사하였다. 미선나무는 전 세계 1속 1종인 식물로 한국에만 분포하는 한국특산식물 중 한 종류이다. 현재까지 공식적으로 총 7곳의 미선나무 자생지가 보고되어 있으며, 대부분의 자생지가 남한 중부지역의 충북지역과 중서부지역의 전북지역에 집중되어 위치하고 있다. 7곳의 미선나무 자생지 중 5곳은 천연기념물로 지정되어 현지 내 보존 및 관리되고 있다. 새롭게 조사된 미선나무 자생지는 충청북도 영동군 영동읍 설계리 인근의 구릉성 산지의 북서사면에 위치하며, 작은 하천이 자생지 하단부에 흐른다. 자생지의 토양은 전형적인 전석지와 암석이 많은 사력지의 형태이고, 토양의 깊이는 약 10~25 cm, pH는 5.0~6.5에 해당되며, 미선나무의 생육지 면적은 약 $3,800 m^2$에 이른다. 생육하는 미선나무 다수가 2~5 개체씩 영양번식과 같은 무성번식방법을 통해 무리지어 있다. 미선나무의 총 개체 수는 700여주에 달하지만, 오직 흰색 꽃을 갖는 기본종만이 분포한다. 이형예현상을 나타내며 종자결실과 깊은 관련이 있는 단주화와 장주화의 분포 비율은 각각 63%와 37%로 관찰된다. 설계리 미선나무 자생지의 상층부 식생은 신갈나무와 물푸레나무가 혼재된 양상을 나타내며, 미선나무가 위치하는 관목층에는 다른 자생지와 유사하게 친화성이 높은 국수나무, 쥐똥나무, 회잎나무, 청가시덩굴 등이 분포한다.

• 한국주거학회논문집
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• 제25권1호
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• pp.23-32
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• 2014

This research progressed space evaluation test with 3D simulation for exterior space of detached housing area among the Seoul spaces of child sex offense in 2010. Based on changing analysis on natural surveillance by spatial changes of each physical element, the purpose is to suggest effective construction planning measure for preventing child sex offense. The results of research are as follows. First, natural surveillance of space's height differences and width differences were compared and analyzed. As the result, footpath shows that stairs of slope didn't make lots of effects on visual block, not block of spatial moving, because of the difference of stair height. Also, in case of parking space, visual connection with footpath is expanded when designing pilotis rather than heightening floor height, so activities of exterior people could be seen more easily. Therefore, natural surveillance was higher. Second, natural surveillance of architectural elements by changes of footpath' width was compared and analyzed. As the result, openness of footpath should be secured rather than openness of architectural element. And, planning autonomy of architectural form could be more expanded when securing openness of footpath.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 춘계학술대회 논문집
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• pp.389-394
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• 2011

Existing FPS(Friction Pendulum System) is isolation system which is possible to isolate structures by pendulum characteristic from ground vibration. Structural natural frequency could be decided by designing the radius of curvature of FPS. Thus, response vibration could be reduced by changing natural frequency of structures from FPS. But effective periods of recorded seismic wave were various and estimation of earthquake characteristic could be difficult. If effective periods of seismic wave correspond to natural frequency of structures with FPS, resonance can be occurred. Therefore, CFPBS(Cone-type Friction Pendulum Bearing System) was developed for controlling the response acceleration and displacement by the slope of friction surfaces. Structural natural frequency with CFPBS can be changed according to position of ball on the friction surface which was designed cone-type. Therefore, Divergence of response could be controlled by CFPBS which had constantly changing natural frequency with low modal participation factor in wide-range. In this study, Seismic performance of CFPBS was evaluated by numerical analysis and shaking table test.

• 한국기후변화학회지
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• 제8권4호
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• pp.287-295
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• 2017

This paper provides a mathematical approach for estimating flood risks due to the effects of climate change by developing a one dimensional (1D) hydraulic model for the mountainous river reaches located close to the Yeongwol thermal power plant. Input data for the model, including topographical data and river discharges measured every 10 minutes from July $1^{st}$ to September $30^{th}$, 2013, were imported to a 1D hydraulic model. Climate change scenarios were estimated by referencing the climate change adaptation strategies of the government and historical information about the extreme flood event in 2006. The down stream boundary was determined as the friction slope, which is 0.001. The roughness coefficient of the main channels was determined to be 0.036. The results show the effectiveness of the riverbed widening strategy through the six flooding scenarios to reduce flood depth and flow velocity that impact on the power plant. In addition, the impact of upper Namhan River flow is more significant than Dong River.