• 한국지진공학회논문집
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• 제1권4호
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• pp.21-28
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• 1997

우리나라 전통 초가삼간의 1/4 축소모델을 제작하여 연약지반 조건에 대한 내진 성능실험을 수행하였다. Imperial Valley 지진파를 사용하여 모델의 파괴 시까지 거동을 분석하였다. 탄성한계 내에서 초가삼간의 고유진동수는 장방향 및 단방향 각각 1.66Hz 및 1.76Hz로 측정되었다. 탄성한게 내에서의 감쇠비는 약 7%이다. 수평방향의 최대 가속도응답은 입력에 비해 감소하며 이는 목조 프레임의 비선형, 비탄상 특성 때문이다. 수평방향의 변위응답은 입력이 증가함에 따라 급격히 증가하여 최대 지반가속도 0.25g에서 모델이 붕괴되었다. 비선형 지진해석 결과와 실험결과를 비교하였다.

• 한국수자원학회논문집
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• 제47권3호
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• pp.297-306
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• 2014

본 연구에서는 해수유입과 강우유출에 따른 용원수로 내의 염분도 분포를 모의하기 위해 EFDC (Environmental Fluid Dynamics Code) 모형을 이용하였다. 유량경계조건은 대표 방류구에서 유출되는 양을 모니터링하여 면적비 유량법으로 산정하였으며, 수위경계조건으로는 시간별 조위 값을 입력하였다. 강우량에 따른 염분도 모의 결과는 일 강우량 245 mm의 유출조건을 반영하였으며, 그 결과 Site 1~2 지점과 망산도 부근 방류구가 위치한 곳에서는 염분도가 0 ppt에 가까운 수치가 나타났으며, 반면 비강우시에는 30 ppt가 넘는 것으로 나타났다. 용원수로 내측지점(Site 2~5)에서의 2010년 1월 1일~12월 31일까지의 염분도 시계열 변화 모의결과와 월별 실측값을 비교하여 나타내었다. 용원수로의 지점별 염분도를 분석한 결과, 내측지점(Site 1~4)과 송정천지점(Site 7~8)에서 염분도가 낮게 나타났다. 이러한 결과를 바탕으로 망산도 부근 염분도를 집중적으로 조사한 결과, 1차 조사결과 누적강우량은 17 mm로 염분도 농도는 21.9~28.8 ppt로 측정되었으며, 2차 조사결과 누적강우 량은 160.5 mm로 염분도 농도는 2.33~8.05 ppt로 나타났다. 결과적으로 용원수로에서는 해수의 순환이 원활하게 이루어지지 않으므로, 이로 인하여 염분도의 차이가 크게 나타났으며 특히 강우시에는 염분도가 급격히 낮아지는 것으로 나타났다.

• 물과 미래
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• 제25권1호
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• pp.93-100
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• 1992

Abstract A study on the Derivation of the Unit Hydrograph using Multiple Regression Moe이. The purpose of this study is to deriver an optimal unit hydrograph suing the multiple regression model, particularly when only small amount of data is available. The presence of multicollinearity among the input data can cause serious oscillations in the derivation of the unit hydrograph. In this case, the oscillations in the unit hydrograph ordinate are eliminated by combining the data. The data used in this study are based upon the collection and arrangement of rainfall-runoff data(1977-1989) at the Soyang-river Dam site. When the matrix X is the rainfall series, the condition number and the reciprocal of the minimum eigenvalue of XTX are calculated by the Jacobi an method, and are compared with the oscillation in the unit hydrograph. The optimal unit hydrograph is derived by combining the numerous rainfall-runoff data. The conclusions are as follows; 1)The oscillations in the derived unit hydrograph are reduced by combining the data from each flood event. 2) The reciprocals of the minimum eigen\value of XTX, 1/k and the condition number CN are increased when the oscillations are active in the derived unit hydrograph. 3)The parameter estimates are validated by extending the model to the Soyang river Dam site with elimination of the autocorrelation in the disturbances. Finally, this paper illustrates the application of the multiple regression model to drive an optimal unit hydrograph dealing with the multicollinearity and the autocorrelation which cause some problems.

• 터널과지하공간
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• 제28권6호
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• pp.555-568
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• 2018

광산에서 효율적이고 안전한 운반 작업을 수행하기 위해서는 덤프트럭이 이동하는 비포장도로의 상태를 정기적으로 점검하고, 그 결과에 따라 체계적인 유지보수를 시행해야 한다. 본 연구에서는 광산의 비포장도로 상태를 주기적으로 조사하는데 사용될 수 있는 스마트폰 애플리케이션을 개발하였다. 개발된 애플리케이션을 사용하면 미국 육군 공병대에서 개발한 Unsurfaced Road Condition Index(URCI) 평가 체계에 따라 필요한 정보를 현장에서 쉽게 수집하고, 비포장도로의 상태를 정량적으로 평가할 수 있다. 부산 일광광산 비포장도로 일부 구간의 조사를 위해 개발된 애플리케이션을 적용하였다. 그 결과 URCI 평가 체계에서 고려되는 7가지 인자들을 사용자 인터페이스 화면을 통해 손쉽게 조사하고, 현장에서 URCI 값을 빠르게 계산하여 비포장도로의 상태를 평가할 수 있었다. 본 연구에서 개발한 스마트폰 애플리케이션은 광산현장의 비포장도로의 상태 조사 및 평가를 위해 유용하게 활용될 수 있을 것이다.

• 국제학술발표논문집
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• The 1th International Conference on Construction Engineering and Project Management
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• pp.655-661
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• 2005

For a hydro power plant project, the headrace tunnel having a finished diameter of 3.3m was constructed in volcanic rocks with well-developed vertical joint and high groundwater table. The intake facility was located 20.3 km upstream of the powerhouse and headrace tunnel of 20 km in length and penstock of 440 m in height connected the intake and the powerhouse. The typical caldera lake, Lake Toba set the geology at the site; the caving of the ground caused tension cracks in the vertical direction to be developed and initial stresses at the ground to be released. High groundwater table(the maximum head of 20 bar) in the area of well-connected vertical joints delayed the progress of tunnel excavation severely due to the excessive inflow of groundwater. The excavation of tunnel was made using open-shield type TBM and mucking cars on the rail. High volume of water inflow raised the water level inside tunnel to 70 cm, 17% of tunnel diameter (3.9 m) and hindered the mucking of spoil under water. To improve the productivity, several adjustments such as modification of TBM and mucking cars and increase in the number of submersible pumps were made for the excavation of severe water inflow zone. Since the ground condition encountered during excavation turned out to be much worse, it was decided to adopt PC segment lining instead of RC lining. Besides, depending on the conditions of the water inflow, rock mass condition and internal water pressure, one of the invert PC segment lining with in-situ RC lining, RC lining and steel lining was applied to meet the site specific condition. With the adoption of PC segment lining, modification of TBM and other improvement, the excavation of the tunnel under severe groundwater condition was successfully completed.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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• pp.888-891
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• 2006

SAR image is not dependent on the weather condition and Sun's electromagnetic energy. But geometric distortions exist in almost all radar image, it need to be correction. The Radarsat-1 SAR images are used to monitoring of moisture acquired in May 1/1998 and May 25/1998. Radarsat-1 C band data is sensitive on moisture condition. Study area is located in Non-san site. It is made up almost agricultural area and a little of forest area. In May, Rice-planting is started in the midland of Korea. So moisture condition is undergoing many changes. Forest area need to be terrain effect removal for accurately results because it is included in layover, shadow, and so on. Results of land-cover moisture condition map are useful tool for fields of agriculture, forestry industry, and disaster.

• 대한원격탐사학회지
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• 제22권5호
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• pp.433-437
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• 2006

SAR image is not dependent on the weather condition and Sun's electromagnetic energy. But geometric distortions exist in almost all radar image, it need to be correction. The Radarsat-1 SAR images are used to monitoring of moisture acquired in May 1/1998 and May 25/1998. Radarsat-1 C band data is sensitive on moisture condition. Study area is located in Non-san site. It is made up almost agricultural area and a little of forest area. In May, Rice-planting is started in the midland of Korea. So moisture condition is undergoing many changes. Forest area need to be terrain effect removal for accurately results because it is included in layover, shadow, and so on. Results of land-cover moisture condition map are useful tool for fields of agriculture, forestry industry, and disaster.

• Archives of Plastic Surgery
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• 제32권2호
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• pp.267-270
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• 2005

The two major concerns in skin grafting are poor color match at the recipient site and donor site morbidity. To overcome the limitations of the classic skin graft, we have used dermis graft-deepithelialized split thickness skin graft-for coverage of small to medium sized wounds. The important aspects of this methods involve the immediate return of epidermis to the donor site to overcome donor site morbidity and restoration of the epidermis at the recipient site by neo epithelization from the adjacent skin. From April of 2001 to July of 2003, the dermis graft was applied to 32 patients. Simultaneously, the regular split thickness skin graft procedure was performed in 33 patients. We compared the healing time in all patients. The scar condition was also evaluated at 2 to 12 months after operation. The entire dermis grafts were reepithelialized in 15.5 days. The skin grafted wounds were healed by 11.8 days. Regarding the donor sites, donor sites of dermis graft healed within 7.5 days. On the contrary those of regular skin graft required 12.8 days. The donor sites of the dermis graft were also superior to those of skin graft in scar quality and patient satisfaction. The dermis graft technique for wound coverage compares favorably to regular skin graft technique in both recipient and donor sites aesthetically and functionally.

• International Journal of Contents
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• 제11권2호
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• pp.69-73
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• 2015

This study was performed to determine the optimal doses of alfentanil or remifentanil (effect-site concentrations) required to prevent pain and other suffering after abdominal general surgery in ICU patients. A total of 52 general abdominal surgical patients (ASA IIIII) requiring artificial ventilatory care in the ICU were provided with either alfentanil (24 patients) or remifentanil (28 patients) through target controlled infusion (TCI). Alfentanil and remifentanil concentrations were titrated up and down until the pain score became less than 3 (VAS; Visual Analogue Score < 3). The effect-site concentrations (ng/ml) of alfentanil or remifentanil required to adequately control postoperative pain in the ICU were 64 +/- 12 and 1.9 +/- 0.5 for intubation with artificial ventilation, 57 +/- 9 and 1.7 +/- 0.7 for intubation with spontaneous ventilation, and 41 +/- 10 and 1.2 +/- 0.5 after extubation, respectively. Pain scores and the corresponding opioid concentrations were independent from respiratory condition. The three effect-site concentrations of alfentanil and remifentanil obtained from this clinical trial using the TCI technique can be a guideline in the administration of the same opioids to relieve the discomfort of ICU patients who have undergone abdominal general surgery.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.1259-1267
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• 2008

One of the most important item for insuring the stability of ground in urban deep excavation site near by major structure such as subway is displacement control of earth retaining wall. The field monitoring system is classified by two types as manual system and automatic system. The application case of latter type of field monitoring is increased because real time measurement is possible in automatic system and that is correspondent with the recent constructional trend. Though the automatic monitoring system is more useful and advanced than manual monitoring system, accuracy of the system is not verified sufficiently. It was examined that the reliance of automatic monitoring system in this paper through the comparison of monitoring result obtained one of deep urban excavation site in which the each type of monitoring system was executed concurrently. Result of the examination is that the two types of monitoring system is generally alike in view of monitoring result, so the engineering reliance of automatic system was confirmed in case site. This study was researched in restricted one case site, so it is expected more precise analysis from security of more data monitored and progressive study.