• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2005년도 춘계학술대회논문집
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• pp.181-184
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• 2005

본 논문에서는 말굽형과 장방형 터널의 기본부의 노면과 벽면의 조도를 Lightscape를 사용하여 계산하였으며, 계산된 결과를 분석하여 보면 노면의 평균조도와 평균균제도는 두 가지 터널 사이에 큰 차이가 없었으며, 벽면조도는 노면에서 높아질수록 두 가지 터널에서 차이가 커지는 것으로 나타났다.

• 한국철도학회논문집
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• 제16권6호
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• pp.454-459
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• 2013

열차가 터널에 고속으로 진입하면, 압력파가 발생한다. 열차 선두부의 진입에 의하여 발생한 압축파는 터널을 따라 진행되어 터널 출구에서 반사되어 팽창파로 되돌아오며, 후미부의 진입에 의하여 발생한 팽창파도 터널을 따라 전파되어 터널 출구에서 압축파로 반사되어 터널 입구로 되돌아 온다. 열차 선두부 및 후미부에 의하여 발생한 이러한 압력파는 터널 입구 및 출구에서 각각 반사되어 터널 내부를 왕복하며, 차량 객실에 탑승한 승객들에게는 이명감을 일으키고, 터널 출구에서는 환경소음의 일종인 미기압파를 발생시킨다. 터널에서의 큰 압력 변동은 터널의 최적 단면적 설계에도 주요 인자로 고려되고 있으며, 차체의 반복 피로 하중으로 작용하므로, 이에 대한 정량적 및 정성적 분석이 필요하다. 본 연구에서는 고정 격자계를 이용하여 개발한 특성 해법을 교행하는 열차에 대하여 적용하였으며, 교행시의 열차 선두부 및 후미부의 경계 조건식을 개발하여, X-t선도와 같이 해석하였다. 해석 결과, 교행 열차의 특정 터널진입 시간에 압력파 간의 상쇄가 일어남을 알 수 있었다.

• 대한물리의학회지
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• 제16권1호
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• pp.63-71
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• 2021

PURPOSE: The purpose of this study was to investigate the effects of trigger finger on pain, muscle strength and function in carpal tunnel syndrome (CTS) patients. METHODS: A total of 60 subjects (30 carpal tunnel syndrome with trigger finger and 30 carpal tunnel syndrome without trigger finger) were assessment for pain, muscle strength (power grip, key pinch , tip to tip pinch, three jaw pinch) and function. The effect sizes of the two groups were compared, and the correlation between the trigger finger and each variable was analyzed. RESULTS: The results showed that there were significantly difference in the pain, muscle strength excluding three jaw pinch and function (p < .05). The results also showed correlation between trigger finger and pain (r = .552), muscle strength excluding three jaw pinch (power grip r = -.296, key pinch r = -.260, tip to tip pinch r = -.285), and function (r = .375). The function of carpal tunnel syndrome patients was related to pain (r = .550) and power grips (r = -.324) of muscle strength. CONCLUSION: In carpal tunnel syndrome patients with trigger finger compared to carpal tunnel syndrome, muscle weakness, pain increase, and function reduction were shown. In addition, trigger finger are correlated with muscle strength, pain and function, and muscle weakness and increased pain affect the daily living of carpal tunnel syndrome patients with triggers finger. Therefore, physical therapy interventions of carpal tunnel syndrome patients with trigger finger should be combined with treatment for muscle strength enhancement as well as pain reduction.

• 한국산학기술학회논문지
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• 제15권3호
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• pp.1272-1278
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• 2014

본 최근 성장하고 있는 해상 풍력의 실험연구에서 풍동시험이 수직형 횡류 풍력발전시스템의 성능을 조사하기 위해 실시되었다. 풍동의 시험 부분은 제한된 크기로 인해 실제 풍력 발전의 입구 안내 베인을 약 1/5로 축소시켰고, 터빈 임펠러의 지름을 모형 임펠러의 1/2로 감소시켰다. 임펠러 블레이드 갯수는 풍력 발전 시스템의 출력에 대한 또 다른 중요한 변수이기 때문에 8개와 16개로 변경하여 시험하였다. 실험 분석 결과, 모형 풍력 터빈의 출력 제동력은 정격 풍속 12m/s에서 블레이드 갯수가 8개 보다 16개일 때 82% 출력이 증가된 278와트로 측정되었고, 정격 제동력은 정격 작동 조건에서 3.9kW로 계산되었다.

• 터널과지하공간
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• 제7권2호
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• pp.100-107
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• 1997

In case of a fire outbreak in a uni-directional road tunnel, the flow of traffic immediately behind the fire disaster will be stalled all the way back to the entrance of the tunnel. Furthermore, when the vehicle passengers try to flee away from the fire toward the entrance of the tunnel, the extremely hot fume that propagates in the same direction will be fatal to the multitudes evacuating, but may also cause damage to the ventilation equipments and the vehicles, compounding the evacuation process. This paper will present the 3-dimensional modelling analysis of the preventive measures of such a fume propagation in the same direction as the evacuating passengers. For the analysis, the fire hazard was assumed to be a perfect combustion of methane gas injected through the 1 m X 2 m nozzle in the middle of the tunnel, and the product of $CO_2$ as the indicator of the fume propagation. From the research results, when the fire hazard occurred in middle of the 400 m road tunnel, the air density decreased around the fire point, and the maximum temperatures were 996 K and 499 K at 210 m and 350 m locations, respectively, 60 seconds after fire disaster occurred, when the fumes were driven out only towards the exit-direction of the tunnel. By tracing the increase of $CO_2$ level over 1% mole fraction, the minimum longitudinal ventilation velocity was found to be 2.40 m/sec. Furthermore, through Analysis of the temperature distribution graphs, and observation of the cross-sectional distribution of $CO_2$ over 1% mole fraction, it was found that the fume did not mix with the air, but rather moved far in a laminar flow towards exit of the tunnel.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.1532-1548
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• 2008

The tunnel type spillways is under construction to increasing water reservoir capacity in Dae-am dam. The tunnel outlet was planned to be made after installing slope stabilization system on natural slope there. Generally, the tunnel outlet is made perpendicularly to the slope, but in this case, it had to be made obliquely to the slope for not interrupting flow of river. Because of excavation in condition of natural slope caused to deflecting earth pressure, the outlet couldn't be made. So, artificial ground made with concrete that it was constructed in the outside of tunnel for producing the arching effect which enables to make a outlet. We were planned tunnel excavation was carried out after artificial ground made. Artificial ground made by poor mix concrete of which it was planned that the thickness was at least 3.0m height from outside of tunnel lining and 30cm of height per pouring. Spreading and compaction was planned utilized weight of 15 ton roller machine. In order to access of working truck, slope of artificial ground was designed 1:1.0 and applied 2% slope in upper pert of it for easily drainage of water. In addition to, upper pert of artificial ground was covered with soil, because of impaction of rock fall from upper slope was made minimum. The tunnel excavation of the artificial ground was designed application with special blasting method that it was Super Wedge and control blasting utilized with pre-percussion hole.

• 설비공학논문집
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• 제20권1호
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• pp.1-10
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• 2008

A transient 3-D numerical simulation was performed to analyze the fire safety in a railway tunnel equipped with a mechanical ventilation system. The behavior of pollutants was studied for the emergency operation mode of ventilation system in case of fire in the center of the rescue station and near the escape route. Various schemes of escape route construction for connection angle($45^{\circ}$, $90^{\circ}$, 135^{\circ}$) and slope($10^{\circ}$) were evaluated for the ventilation efficiency in the fire near the escape route. From the results, it was shown that the mode of the ventilation fan operation which pressurizes the tunnel not under the fire and ventilates the smoke from the tunnel under the fire is most effective for the smoke control in the tunnel in case of the fire occurrence. It was also shown that the blowing of jet fan from the rescue tunnel to the main tunnel should be in the same direction as the flow direction in the main tunnel arising from the traffic and the buoyancy.

• 대한기계학회논문집B
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• 제21권1호
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• pp.89-98
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• 1997

Compression waves propagating in a high speed railway tunnel impose large pressure fluctuations on the train body or tunnel structures. The pressure fluctuations can cause ear discomfort for the passengers and increase the aerodynamic resistance of trains. As a fundamental research to resolve the pressure wave phenomenon in the tunnel, a steady theory of Chester-Chisnell- Whitham was applied to a simple shock tube with a sudden cross-sectional area reduction to model trains inside the tunnel. The results of the present theoretical analysis were compared with the experiments of the shock tube. The results show that the reflected compression wave from the model becomes stronger as the strength of incident compression wave and the blockage ratio increase. However, the compression wave passing through the model is not strongly dependent on the blockage ratio. The theoretical results are in good agreement with the experiments.

• 산업기술연구
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• 제24권B호
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• pp.107-116
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• 2004

This thesis is results of experimental works on the behavior of the cut-and-cover tunnel. Centrifuge model tests were performed to simulate the behavior of the cut-and-cover tunnels having cross sections of national road and subway tunnels. Model experiments were carried out with changing the cut slope and the slope of filling ground surface. Displacements of tunnel lining resulted from artificially accelerated gravitational force up to 40g of covered material used in model tests, were measured during centrifuge model tests. In model tests, Jumunjin Standard Sand with the relative density of 80 % and the zinc plates were used for the covered material and the flexible tunnel lining, respectively. Basic soil property tests were performed to obtain it's the property of Jumumjin Standard Sand. Shear strength parameters of Jumunjin Standard Sand were obtained by performing the triaxial compression tests. Direct shear tests were also carried out to find the mechanical properties of the interface between the lining and the covered material. Compared results model tests estimation with respect to displacements of the lining.

• 한국환경과학회지
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• 제17권7호
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• pp.733-741
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• 2008

The object of this study is the safety insurance of the dam to provide for the extraordinary flood. The safety insurance of the reservoir was taken by the preparatory discharge using the temporary division tunnel used during the reservoir construction. In this study, the Sungju reservoir was simulated. The existing discharge facilities of the intake tower of the Sungju reservoir could nat have influence on the flood control. When the Sungju reservoir operated to begin preparatory discharge for 48 hrs by the temporary diversion tunnel that have discharge of an 20-years frequency, the water level was lowered about 20 cm. When the Sungju reservoir operated to begin the continuous discharge after the preparatory discharge, the water level was lowered over 1m but the downstream at risk was caused by the resulted. If it is possible to operate to begin the preparatory discharge of the reservoir for 24 hrs by the temporary diversion tunnel, that will improve the flood control faculty of the reservoir without other hydraulic structure and safety of the Sungju reservoir will be higher.