• Title/Summary/Keyword: Drained

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Design of the secondary tunnel lining using a ground-primary support-secondary lining interaction model

  • Chang, Seok-Bue;Seo, Seong-Ho;Lee, Sang-Duk
    • 한국지구물리탐사학회:학술대회논문집
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    • 2003.11a
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    • pp.109-114
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    • 2003
  • It is the common practice to reinforce excessively the secondary tunnel lining due to the lack of rational insights into the ground loosening loads. The main load of the secondary lining for drained-type tunnels is the ground loosening. The main cause of the load for secondary tunnel lining is the deterioration of the primary support members such as shotcrete, steel ribs, and rockbolts. Accordingly, the development of the analysis model to consider the ground-primary supports-secondary lining interaction is very important for the rational design of the secondary tunnel lining. In this paper, the interaction is conceptually described by the simple mass-spring model and the load transfer from the primary supports to the ground and the secondary lining is showed by the characteristic curves including the secondary lining reaction curve for the theoretical solution of a circular tunnel. And also, the application of this model to numerical analysis is verified in order to review the potential tool for practical tunnel problems with the complex conditions like non-circular shaped tunnels, multi-layered ground, sequential excavation and so on.

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Effects of PVC Pipe Underdrainage on the Growth of Rice Plants (PVC 파이프 암거배수가 벼의 생육에 미치는 영향)

  • 임웅규
    • Journal of Plant Biology
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    • v.20 no.2
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    • pp.103-107
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    • 1977
  • Two sample varieties of Yushin and Jinheung were used for the experiment in low-level wetty paddy field which was arranged with PVC pipe underdrainage of 6m in distance and 60cm, 90cm, and 120cm in depth and control, using sprit plot design with three replications. On the yield of brown rice, Yushin was increased by 24.8% in the 90cm plot and Jinheung by 16.7% in the 120cm plot, respectively, over the control. The ratio of matured grains of these two varieties was increased significantly by the underdrainage and the number of grains per head of Yushin was also increased in drained plots. Otherwise, the underdrainage enhanced the plant height in the early growth of rice plant and further increased the culm height and panicle length. It seemed that these results might enhance the light-receiving effciency in the latter growth of rice plant and bring about the effect fo increased yields by the underdrainage.

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폐광 전후 삼탄 광산배수의 수질특성과 의의

  • 정영욱;강상수;임길재;홍성규;조원재;조영도;전호석;민정식
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2003.09a
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    • pp.422-425
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    • 2003
  • This study was carried out to apprehend the variation of quality of mine drainage in the abandoned Samtan coal mine. After closure of coal mine, although still pumping, water level in underground was raised to loom and the concentration of some elements such as Fe and Mn was elevated. At present, the worst pollution source in this area is too the acidic leachate drained from uncovered mine waste impoundment. The flow rate of mine drainage from the adit is ave. about 20,000t/d. If water were flooded and deteriorated due to stopping pumping, the impact of the mine drainage on the stream around the abandoned mine would be more severe. Therefore, It is considered that the prediction of water quality of mine drainage from the adit after stopping pumping will be very important with a view to establishing countermeasures.

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Stress-Strain Behaviour of Overconsolidated Clay with Loading Rate (하중재하속도에 따른 과압밀점토의 응력-변형 거동)

  • 김병일;신현영;이승원;김수삼
    • Proceedings of the Korean Geotechical Society Conference
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    • 2001.03a
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    • pp.239-244
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    • 2001
  • Natural clayey soils or improved grounds are in a overconsolidated conditions due to changes in vertical stress and pore pressures, desiccation, ageing and so on. These grounds show inelastic stress-strain behaviour characteristics within all range of strain except very small strain (${\gamma}$$\_$s/$\leq$10 ̄$^3$∼10 ̄$^4$%) when construction, such as excavations and retaining walls, is performed. Also it strongly depends on loading rate of current stress path and recent stress path. This study carried out drained stress path tests by varying loading rate of current and recent stress path. Test results indicated that stress-strain behaviour of overconsolidated clay depends on loading rate, especially loading rate of current stress path.

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Shearing Behaviors of the Soft Marine Clay in Undrained and Drained Conditions (연약해성점토의 비배수 및 배수 전단 거동)

  • 이영휘;김용준;정강복
    • Journal of the Korean Geotechnical Society
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    • v.17 no.5
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    • pp.29-36
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    • 2001
  • 한반도 남해안의 광양만에서 채취한 연약 해성점토의 물리적 및 역학적 특성을 조사하기 위한 일련의 실내시험을 수행하였다. 물리적 성질 및 압밀시험 결과의 분석에 따르면, 시험에 사용된 시료는 정규압밀점토로 나타났다. 압밀비배수 삼축시험 결과로부터 새로운 간극수압계수(C)를 제안하였고, 이 계수는 유효응력경로를 예측하기 위한 방정식에 적용되었다. 또한, 비배수조건에서 전단변형률은 오로지 응력비만의 함수라는 사실이 실험결과로부터 밝혀졌다. 따라서 비배수 조건에서의 전단변형률 계산식이 제안되었으며, 이들 관계식을 이용하여 비배수(CIU) 및 배수조건(CID)에서의 점토의 거동을 예측하기 위한 새로운 구성방정식이 제안되었다. 이 구성방정식은 Roscoe와 Poorooshasb이 제안한 증분응력-변형률 이론을 기초로 하였으며, 제안된 구성방정식을 적용하여 예측한 배수전단특성을 실측된 결과에 매우 근접하는 경향을 나타내었다.

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Lymphadenopathy (림프절 종대)

  • Chung, Nack-Gyun
    • Clinical and Experimental Pediatrics
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    • v.51 no.8
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    • pp.797-803
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    • 2008
  • Lymphadenopathy is a common problem in children and adolescents. A wide variety of diseases and conditions may present as lymphadenopathy and an understanding of these conditions is essential to determine the most appropriate diagnostic work-up for each patient. A detailed history and physical examination with careful attention to the anatomical regions drained by the involved lymph node or mass often leads to the appropriate diagnosis. A majority of these children will prove to have a benign disorder; however, it is important for the pediatrician to have an appreciation for the malignant diseases or serious systemic illnesses that may initially present with lymphadenopathy, to ensure the timely diagnosis of a serious disease.

Liver abscess due to Klebsiella pneumoniae in a healthy 12-year-old boy

  • Yoon, Da Hye;Jeon, Yeon Jin;Bae, E Young;Jeong, Dae Chul;Kang, Jin Han
    • Clinical and Experimental Pediatrics
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    • v.56 no.11
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    • pp.496-499
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    • 2013
  • Pyogenic liver abscess (PLA) is rare in healthy children. We report a case of PLA in an immunocompetent 12-year-old boy. Percutaneous catheter drainage was performed for the abscess. In addition, parenteral antibiotics were administered for 3 weeks. Klebsiella pneumoniae was detected in the culture of blood and drained fluid. Here, we present this case and a brief review of the literature on this subject.

Hematoma in Neck after Stellate Ganglion Block (성상신경절 차단후에 발생한 경부혈종)

  • Han, Young-Jin;Choi, Huhn
    • The Korean Journal of Pain
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    • v.7 no.2
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    • pp.270-272
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    • 1994
  • A 43 year old male patient injured in a traffic accident was admitted to the department of general surgery for the treatment of spleen rupture and multiple rib fractures. After subphrenic abscess occurred after splenectomy was treated. After 50 days of admission, left facial palsy occurred with sensory neural hearing loss, and tinnitus by longitudinal fracture of left temporal bone. The patients was consulted to pain clinic for further evaluation and treatment. The patient was treated with stellate ganglion block with 1% lidocaine 6ml one time daily. On 19th day, stellate ganglion block was given as usual, and the patient complained of pain in the neck and headache the next day. Two days later, mild fever elevation and hematoma in the neck were found. Hematoma was drained with hemovac. Ruptured muscular branch of vertebral artery was ligated surgically but the ligation was released in the next day and the hematoma was removed and the artery religated. Five units of packed RBC were transfused during the period and the patient was discharged without any sequelae.

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Pyrite Concentration and Paleoenvironmental Change of the Hiroshima Delta (Japan) (일본 히로시마 삼각주 퇴적층의 황철석 함량과 고 환경변화)

  • Jinadasa Katupotha
    • The Korean Journal of Quaternary Research
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    • v.3 no.1
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    • pp.47-54
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    • 1989
  • Pyrite ($FeS_2$) content in brackish and salt marsh sediments is relatively higher than the amount in freshwater marsh sediments. Different values of pyrite sulfur ($FeS_2$-S) content in sediments from the Hiroshima Delta indicate that poorly drained salt marsh had developed between 27.0m and 28.0m below mean sea-level and palaeo-sea-level was constant for several hundreds of years in the same depth during the early Holocene Epoch.

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Modeling Infiltration and Redistribution for Multistorm Runoff Events

  • 유동렬;이강근
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2000.11a
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    • pp.74-77
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    • 2000
  • Infiltration and water flow in the upper soil layer of a deep water table aquifer are modeled for multistorm runoff events. The infiltration process is developed using the sharp wetting front model of Green and Ampt, and the following redistribution process is modeled using the gravity drained rectangular approximation. The Brooks-Corey model [Brooks and Corey, 1966] is adopted to relate the effective soil saturation, the tension head, and the unsaturated hydraulic conductivity Firstly, the infiltration and redistribution model is developed for a single stom runoff event. Then a couple of events combined for multistorm runoff events. In the later case, infiltration rate of the second rainfall is strongly influenced by the length of the rainfall hiatus and soil moisture profile.

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