• Wind and Structures
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• 제22권2호
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• pp.161-184
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• 2016

Long-span suspension bridges have evolved through the years and with them, the bridge girder decks improved as well, changing their shapes from standard box-deck girders to twin box and multi-box decks sections. The aerodynamic characteristics of the new generation of twin and multiple-decks are investigated nowadays, to provide the best design wind speeds and the optimum dimensions such bridges could achieve. The multi-box Megane bridge deck is one of the new generation bridge decks, consisting of two side decks for traffic lanes and two middle decks for railways, linked between them with connecting beams. Three-dimensional CFD simulations were performed by employing the Large Eddy Simulation (LES) algorithm with a standard Smagorinsky subgrid-scale model, for $Re=9.3{\times}10^7$ and angles of attack ${\alpha}=-4^{\circ}$, $-2^{\circ}$, $0^{\circ}$, $2^{\circ}$ and $4^{\circ}$. Also, a wind tunnel experiment was performed for a scaled model, 1:80 of the Megane bridge deck section, for $Re=5.1{\times}10^5$ and the aerodynamic static coefficients were found to be in good agreement with the results obtained from the CFD-LES model. However the aerodynamic coefficients determined individually, from the CFD-LES model, for each of the traffic and railway decks of the Megane bridge, varied significantly, especially for the downstream traffic deck. Also the pressure distribution and the effect of the spacing between the connecting beams, on the wind speed profiles showed a slight increase in turbulence above the downstream traffic and railway decks.

• 한국건설순환자원학회논문집
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• 제3권2호
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• pp.165-170
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• 2015

파이프랙 구조물은 고온 고압의 파이프를 지지하며 플랜트의 운전 안전성을 좌우하는 매우 중요 구조물이다. 따라서, 파이프랙 구조물의 손상은 산업 전반에 부정적인 파급효과를 가져옴과 동시에 인명 및 재산상의 막대한 피해까지 가져오게 된다. 특히, 파이프랙 구조물은 외부환경에 노출되어 있어, 구조물의 적절한 설계 및 유지관리를 위하여 환경적 영향에 의한 거동 특성을 평가할 필요가 있다. 따라서, 가장 널리 설계되어지는 하나의 파이프랙 구조물을 대상 구조물로 선정하여 열-구조 연성해석을 실시하여 파이프랙 구조물의 온도분포와 열응력을 평가하였다. 외부 환경적 요인으로는 국내의 여수지역과 중동의 사우디 지역을 고려하여 파이프의 운전조건과 함께 외부환경 영향인자에 대한 고려 필요성을 검증하였다.

• 대한한의진단학회지
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• 제16권3호
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• pp.1-10
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• 2012

Objectives: The purpose of this study is to observe clinically the anti-cholesterol effects on the prescription of red onion. Materials and methods: The subject of study were middle-aged people. We measured clinically physiological index, body composition, radial arterial pulse wave after 2 month by taking medicine (the prescription of red onion) Results: The study results were as follows. 1. Systolic and diastolic blood pressure of subjects were decreased significantly in the statistics. 2. Total cholesterol and low-density lipoprotein were decreased significantly after 2 month taking medicine. Triglyceride was decreased after 2 month but there was no significant difference and high density lipoprotein was increased after 2 month but there was no significant difference. 3. Waist-Hip ratio, body mass index and body fat percentage were decreased significantly in the statistics, after 2 month taking medicine. 4. HR was increased significantly in the statistics after 2 month but ESV and ECO were decreased signficantly in the statistics after 2 month taking medicine. 5. Pulse wave energy was increased after 2 month but there was no significant difference in the statistics. 6. RAI was decreased significantly in the statistics after 2 month taking medicine. Conclusion: The prescription of purple onion was showed significant change in physiological index, character of body composition, blood circulation index, pulse wave energy and RAI. Therefore it was showed the effect of anti-cholesterol blood circulation clinically. In the future, with diversified study on effect of prescription of purple onion, Oriental medicinal herbs will be used extensively.

• 한국산학기술학회논문지
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• 제12권2호
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• pp.1032-1037
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• 2011

본 연구에서는 전처리 공정을 거친 천연가스로부터 에탄 이상의 성분을 회수하기 위한 탈메탄탑에 대한 전산모사와 공정 최적화를 수행하였다. 전처리된 천연가스는 탈메탄탑 상부의 차가운 기상류와의 열교환 및 프로판 냉동 사이클이 포함된 예냉공정을 거친 후에 기상과 액상이 분리된다. 기상은 터보 팽창기를 거치면서 생산되는 동력을 residue gas의 압력을 높이기 위한 압축기에 전달한 후에 부분적으로 응축되어 탈메탄탑 상부로 주입된다. 액상류는 줄-톰슨 팽창 밸브를 거친 후 더욱 냉각되어 탈메탄탑의 중간부로 주입된다. 원료 대비 에탄의 회수율은 80% 이상으로 정하였으며, 탈메탄탑의 탑저에서 에탄에 대한 메탄의 몰비는 0.0119로 정하였다. 한편 프로판 냉동 사이클의 heat duty를 최소화시키기 위해서 원료를 분리하여 side reboiler와 열교환시킴으로써 냉열의 일부를 회수할 수 있었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.719-720
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• 2007

Korea, for the first time in the world, constructed 765 kV double circuits transmission lines, which has 3 phases and 6 bundles with vertical arrangement using steel pipes in 1998. Also in 2002, we developed 765kV outdoor full GIS substation with self-developed technology. KEPCO accumulated a wealth of technologies for 765kV system construction and operation, and are listed 5th in technology field in the world. With this advanced technologies, we are developing oversea business. We started with a projects, 'Development Study on the Power System Network Analysis in Myanmar' in 2001, and continued the project to transmission design, consulting for transmission technology including the education of foreign trainees in south-east and middle east asia. Currently, 12 overseas businesses including 330kV transmission system consulting in Ghana, are in progress. In 2007, beginning with 750 kV transmission consulting in China, we are operating ATT(Advanced Transmission Technology) training program, which educate engineers of government and utilities company from China, Myanmar, Cambodia, Laos and Cambodia. However, for the successful development study on the power system, design of the power system and the training service, it is essential to standardize load design criteria in consideration of temperature, wind speed, air pressure and density, etc. of the other countries. Therefore, in this paper, standardized load design criteria for Cambodia, Laos, Myanmar is explained.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권6호
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• pp.48-55
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• 2013

This study aimed at characterizing unsaturated zone at the source zone area contaminated by DNAPL and investigating feasibility of soil vapor extraction (SVE). Five boreholes with three multi-level screens at the depth of 3.0~4.5 m, 5.5~7.0 m, and 8.0~12.0 m were installed at the source zone. Pneumatic tests were performed to determine the permeability of porous medium. Permeability was estimated to be 81.6 to 203.7 darcy, depending on the applied solutions, which was contradicted by grain size analysis of cored soil samples leading to 3.51 darcy. This is due to air flow through gravel pack during the early stage of pneumatic test. Pressure-drawdown curve in the late stage also well showed the leaky aquifer type, indicating air leakage to the ground. Air flow tests were also carried out to investigate air flow connectivity between multi-level wells, indicating that the horizontal air flow was well developed between the lower screens of the wells, not between the upper and middle screens due to the leakage to the surface. For the SVE test, there was no noticeable variation in TCE vapor concentration between three different test runs: 1. 8 hours daily for 5 days, 2. 24 hours together with air blowing at another well (BH1), 3. five consecutive days. Even for five-day consecutive test, total amount of removed TCE was estimated only to be as low as 46.5 g.

• Journal of Korean Neurosurgical Society
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• 제30권sup2호
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• pp.364-367
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• 2001

A 4-month-old female patient admitted because of hydrocephalus. She was premature infant with germinal matrix hemorrhage at gestational period 27 wks. A ventriculoperitoneal shunt with a low-pressure type valve was placed. Follow-up CT scan obtained 3 months after VP shunt placement, revealed a new Lt. middle cranial fossa cyst. The girl was readmitted to hospital at 7 months after VP shunt placement, complaining of lethargy and vomiting. A CT scan was demonstrated a increase in size of a cyst, She subsequently underwent a left-sided pterional craniotomy with partial excision of membrane and cyst fenestration into the basal cisterns. Follow-up CT scan after 18 months revealed reaccumulation of cyst, the girl was reoperated on. After 2 months, the size of cyst was not decreased. Finally, She underwent a cystoperitoneal shunt. Follow-up CT scan after 5 months was demonstrated disappeared cyst and reexpansion of brain parenchyma. We report the development of a symptomatic sylvian fissure arachnoid cyst developed after ventriculoperitoneal shunt.

• 한국지형학회지
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• 제15권2호
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• pp.25-35
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• 2008

2006년 7월의 태풍 에위니아와 빌리스에 의한 집중호우로 인해 급경사의 사면이 많고 기복이 큰 강원도 지역에서 토사재해가 크게 발생하였다. 특히 한계령을 관통하는 국도 44호선 도로는 단층선곡을 따라 건설되어 토사재해의 가능성이 가장 높은 편에 속하는 지역이다. 오색천 주변에서 발생한 토석류는 호우에 의해 공극수압이 상승하고 사면부의 무게가 증가하면서 발생한 능선부와 산정부의 산사태에 의해 촉발되었다. 또한 기존의 붕적물 또는 계안퇴적물에 가해진 하천의 압력에 의해서도 특히 공격사면 쪽에서 많은 토석류가 발생하였다. 하천의 상류부에서는 도로주변의 급경사의 절개지와 사면부의 얇은 풍화층에서 산사태가 발생한 반면, 중류부에서는 계류부의 토석류가 도로변의 배수구조물 용량을 초과하여 월류가 발생하여 도로와 교량이 파괴되었고, 하류부에서는 하천범람에 의한 계류부 양안의 침식과 토석류에 의한 피해가 가장 크게 나타났다. 하류부 퇴적층의 경우 토석류가 일회성이 아니라 과거 수차례 더 발생했었다는 사실을 보여주고 있다. 따라서 기후변화와 관련하여 호우의 빈도와 강도가 높아질 것으로 예측되는 만큼 추후 토사재해와 관련된 정보시스템의 구축과 관리시스템에 대한 연구가 절실히 요구된다.

• Physical Therapy Rehabilitation Science
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• 제7권2호
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• pp.78-82
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• 2018

Objective: The purpose of this study was to determine the effect of wearing a pelvic compression belt on ball speed and accuracy in instep shoots of youth soccer players. Design: Randomized cross-over design. Methods: We included 20 male junior soccer players with experience of more than 5 years. Participants were randomly assigned to two conditions: application of a pelvic compression belt and instep shooting or no application. Instep shooting was performed three times at a distance of 20 meters from the position of the goal post, and the ball speed was measured using a speed gun at a position 5 meters behind the goal post. The shooting accuracy was measured based on a 5-point scale. The shooting accuracy was measured by scoring 5 points at 2.44 meters in the middle of the goal area of area A, 3 points at 2.44 meters in the goal area of area B, and 0 in the case of shooting outside the goal area C. Results: After applying a pelvic compression belt, the mean speed of the ball was significantly increased (p<0.05). The maximum speed of the ball was significantly increased (p<0.05). The accuracy of the ball was significantly increased (p<0.05). Conclusions: Through this study, we expect that the use of the pelvic compression belt can be applied as a training method to improve the shooting ability of soccer players. Clinically, pelvic compression belts are expected to help rehabilitation soccer players to improve their shooting accuracy.

• PNF and Movement
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• 제18권1호
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• pp.35-44
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• 2020

Purpose: The purpose of this study was to investigate the effect of the simultaneous abdominal drawing-in maneuver (ADIM) on the muscle activity of the ipsilateral trunk and leg during proprioceptive neuromuscular facilitation (PNF) leg flexion, adduction, and external rotation with knee flexion (D1) patterns. Methods: The participants were 20 healthy adult males and females (18 males and 2 females). The maneuvers were performed by a physical therapist who fully understands the PNF leg patterns (D1) and their application in clinical practice. The participants were trained and allowed to practice for 15 minutes prior to applying ADIM, to ensure adequate learning as evidenced by the pressure biofeedback unit. In this study, we measured the muscle activity of the trunk and leg when the PNF leg pattern (D1) was performed by the physical therapist either sustaining or releasing the ADIM. Muscle activity was measured on the right transverse abdominis muscle (TRA), the external abdominal oblique muscle (EO), the internal abdominal oblique muscle (IO), the erector spinae muscle (ES), the vastus medialis oblique muscle (VMO), the vastus lateralis oblique muscle (VLO), and the tibialis anterior muscle (TA) and compared using the mean values from averaging three repeated measurements. Results: The muscle activity of the transversus abdominis, the external abdominal oblique, the internal abdominal oblique, the vastus medialis oblique, and the vastus lateralis oblique was significantly greater (p < 0.05), and the muscle activity of the erector spinae was significantly less (p < 0.05) during PNF leg pattern (D1) when the ADIM contraction was sustained compared to when it was not. Conclusion: These results suggest that sustaining ADIM during PNF leg pattern (D1) training increases the trunk and leg muscle activity, resulting in more effective training.