• 제목/요약/키워드: Case histories

검색결과 220건 처리시간 0.026초

터널 건설 예정지구에서의 전기비저항 탐사와 전자탐사의 적용을 통한 연약대 탐지에 대한 사례 연구 (A case histories on the detection of weak zone using electrical resistivity and EM surveys in planned tunnel construction site)

  • 권형석;송윤호;이명종;정호준;오세영;김기석
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2002년도 봄 학술발표회 논문집
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    • pp.63-70
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    • 2002
  • In tunnel construction, the information on the rock quality and the location of fault or fracture are crucial for economical design of support pattern and for safe construction of the tunnel. The grade of rock is commonly estimated through the observation with the naked eye of recovered cores in drilling or from physical parameters obtained by their laboratory test. Since drilling cost is quite expensive and terrains of planned sites for tunnel construction are rough in many cases, however, only limited information could be provided by core drilling Electrical resistivity and EM surveys may be a clue to get over this difficulty. Thus we have investigated electrical resistivity and EM field data providing regional Information of the rock Quality and delineating fault and fracture over a rough terrain. In this paper, we present some case histories using electrical resistivity and EM survey for the site investigation of tunnel construction. Through electrical resistivity and EM survey, the range and depth of coal seam was clearly estimated, cavities were detected in limestone area, and weak zones such as joint, fault and fracture have been delineated.

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인적재난의 피해 사례 및 개선방안 (Case Histories of Damage and Improvement Schemes for Human Disasters)

  • 전상수;김재민;장현민
    • 한국방재학회 논문집
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    • 제8권2호
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    • pp.83-90
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    • 2008
  • 우리나라는 1960년대부터 급속한 경제성장과 함께 사회기반시설물이 건설되었다. 현재 이러한 시설물은 부적절한 유지관리와 더불어 노후화 되었으며 시민들은 인적재난에 대한 인식이 부족하다. 추가로, 정부는 인적재난에 대응할 수 있는 적절한 법과 규칙이 적절하게 마련되지 않은 상황이다. 인적재난은 사회적 문제로 대두되고 있으며 사회적 경제적 손실을 야기하고 있으므로 인적재난에 관한 개선방안이 요구되고 있다. 본 연구에서는 인적재난 피해종류에 따른 피해유형 사례와 개선방안 사례를 종합적으로 분석하였다.

Imported human babesiosis in the Republic of Korea, 2019: two case reports

  • Hyun Jung Kim;Min Jae Kim;Hyun-Il Shin;Jung-Won Ju;Hee-Il Lee
    • Parasites, Hosts and Diseases
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    • 제61권1호
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    • pp.72-77
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    • 2023
  • Human babesiosis is a tick-borne disease induced by the genus Babesia and has been significantly reported in the Republic of Korea. This report shows the cases of 2 patients with human babesiosis who traveled to the USA in 2019. The 2 patients experienced fever and had travel histories to babesiosis-endemic regions. The diagnoses of both cases were verified by the identification of Babesia-infected red blood cells on blood smears. One patient was found to be infected with Babesia microti using polymerase chain reaction (PCR) for 18S rRNA, which discovered the phylogenetic link to the B. microti strain endemic in the USA. The 2 patients recovered from fever with subsequent hemoparasite clearance. Babesiosis could be diagnosed in anyone with histories of travel to babesiosis-endemic countries and tick bites. Furthermore, Babesia-specific PCR is required for determining geno-and phenotypic characteristics.

블록식 보강토 옹벽의 하자발생 사례 분석 (Lessons Learned from Failure of Geogrid-Reinforced Segmental Retaining Wall)

  • 신은철;오영인;김종인
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2001년도 가을 학술발표회 논문집
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    • pp.329-336
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    • 2001
  • The numbers of geogrid-reinforced walls are widely used in Korea. This papers present the results of two failure case histories of geogrid-reinforced segmental retaining walls. The geological background of the construction sites, detailed construction sequences, and the amount of rainfall were examined. The failure of these reinforced walls are caused by the improper drainage system and foundation treatment, too sharpened curvature of corner work, and too high height of wall.

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Development of seismic fragility curves for high-speed railway system using earthquake case histories

  • Yang, Seunghoon;Kwak, Dongyoup;Kishida, Tadahiro
    • Geomechanics and Engineering
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    • 제21권2호
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    • pp.179-186
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    • 2020
  • Investigating damage potential of the railway infrastructure requires either large amount of case histories or in-depth numerical analyses, or both for which large amounts of effort and time are necessary to accomplish thoroughly. Rather than performing comprehensive studies for each damage case, in this study we collect and analyze a case history of the high-speed railway system damaged by the 2004 M6.6 Niigata Chuetsu earthquake for the development of the seismic fragility curve. The development processes are: 1) slice the railway system as 200 m segments and assigned damage levels and intensity measures (IMs) to each segment; 2) calculate probability of damage for a given IM; 3) estimate fragility curves using the maximum likelihood estimation regression method. Among IMs considered for fragility curves, spectral acceleration at 3 second period has the most prediction power for the probability of damage occurrence. Also, viaduct-type structure provides less scattered probability data points resulting in the best-fitted fragility curve, but for the tunnel-type structure data are poorly scattered for which fragility curve fitted is not meaningful. For validation purpose fragility curves developed are applied to the 2016 M7.0 Kumamoto earthquake case history by which another high-speed railway system was damaged. The number of actual damaged segments by the 2016 event is 25, and the number of equivalent damaged segments predicted using fragility curve is 22.21. Both numbers are very similar indicating that the developed fragility curve fits well to the Kumamoto region. Comparing with railway fragility curves from HAZUS, we found that HAZUS fragility curves are more conservative.

의안(醫案)을 통한 신종 인플루엔자의 한의학적 대처방안 (A Study on Traditional Korean Medical Countermeasures of Influenza A by Case Histories)

  • 안상영;한창현;권오민;박상영;안상우
    • 대한한의학원전학회지
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    • 제22권4호
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    • pp.221-239
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    • 2009
  • Background: The recent outbreak of the novel strain of influenza A (H1N1) virus has raised a global concern of the future risk of pandemic. Traditional Korean Medicine(TKM) has been combatting against contagious diseases and developed its own particular and efficient way in treating those diseases. Objectives: Provide a distinctive and effective TKM method in understanding the principles of treatment, prevention, and contraindications against influenza A through case histories. Method: We revised case histories of eminent doctors of Ming and Qing dynasties according to their clinical manifestations similar to those of influenza A. We also verified prescriptions of the "Dong-uibogam(東醫寶鑑)" through examining clinical practices of China today. Results: 1. The subtypes of Warm disease; Wind Warmth and Pestilence has the most similar clinical manifestation in comparison to Influenza A. Specifying these terms is important in recognizing and classifying various diseases under the name of Warm disease. 2. TKM considered not only external factors but also individual factors like general condition, diet, emotion, constitutional types, etc in the treatment of febrile diseases. 3. TKM developed a new way in the treatment of contagious diseases. considering the characteristics of each pathogen. TKM described the Warm pathogen being light as a feather, which enters through the nose, principally affecting the Lung. Therefore, they emphasized treatment with Pungent Sweet Cooling Moistening[辛甘凉潤] method. 4. As the conservation of fluid and humor is the primordial concern in the treatment of Warm disease, they restricted release of the exterior with pungent-warm and purgation method. The purgation methods was used exclusively to decrease fever and preserve fluid and humor. 5. The only differentiating characteristics of Influenza A with seasonal influenza are vomiting and diarrhea. Case research revealed the possibility of these manifestations to be a mechanism of restoration. 6. TKM provides alimento prevention method like Mint Pear Porridge, mung bean, and etc also combination of herbal medicine. Also emphasized in the conservation of essence for the prevention of contagious diseases. Conclusions: TKM developed its unique way in understanding the pathogenesis, diagnosis, treatment, and prevention of contagious diseases and formed its independent scheme of Warm Disease. This knowledge in febrile contagious disease is relevant today in providing diverse treatment and prevention for influenza A.

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급경사지 붕괴위험 판단을 위한 강우기반의 한계영역 설정 기법 연구 (Proposed Landslide Warning System Based on Real-time Rainfall Data)

  • 김홍균;박성욱;여강동;이문세;박혁진;이정현;홍성진
    • 지질공학
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    • 제26권2호
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    • pp.197-205
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    • 2016
  • 급경사지 붕괴 위험을 판단하기 위한 반감계수 기반의 한계선 설정은 재해이력 자료가 반드시 필요하다. 그러나 전국적으로 재해이력 자료는 절대적으로 부족하며, 지역별로 편중되어 있어 신뢰도 높은 한계선 설정은 어려운 문제이다. 본 연구에서는 재해이력 자료 없이 급경사지 붕괴 위험을 판단하기 위한 한계영역 설정 기법을 제안하였다. 반감계수가 적용된 과거 10년간의 강우자료를 도시한 후 가장 바깥에 위치한 점들을 연결하여 기준선을 설정한다. 실시간 작용강우가 기준선을 넘어가면 경보가 발령되는 시스템을 구축하였으며, AWS (자동기상관측) 지점별 기준선 설정을 통해 전국적 활용이 가능하다. 과거 시뮬레이션 방법을 통한 신뢰성 검증 결과, 12개 현장 중 10개 현장에서 실제 붕괴 발생 전 경보 발령이 가능했던 것으로 나타났다. 실제 붕괴 발생 30분 전에 경보 발령이 가능했던 현장은 총 8개소로 약 67%의 정확도를 보였다. 본 모델의 활용성을 높이기 위해서는 전국적인 강우 DB구축과 지역별 한계영역 보정에 대한 추가 연구가 진행되어야 할 것으로 판단된다.

그라운드 앵커의 하중전이 현상에 대한 연구 (A Study on Load Transfer of Ground Anchors)

  • 김낙경;박완서
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 1999년도 가을 학술발표회 논문집
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    • pp.441-448
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    • 1999
  • The load distribution in a ground anchor is very complex because it involves three different materials(soil, grout, and steel), which sometimes act as composite sections (bonded length) or separately (unbounded length). Therefore it is very hard to understand load transfer mechanism on the anchor. In order to understand the load transfer, it is essential to consider the load distribution In the three different materials. On these purposes, full scale anchor test is planned on the geotechnical site at Sunkyunkwan University Prior to the test, modeling and analyses of the load transfer mechanism were performed on the data from the case histories.

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위해성에 근거한 유류오염 농지의 복원방안에 대한 고찰 (A Consideration on the Risk-Based Remedial methods of Petroleum-contaminated Farmlans)

  • 유찬;류시창;이근후;조병진
    • 한국농공학회:학술대회논문집
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    • 한국농공학회 2002년도 학술발표회 발표논문집
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    • pp.409-412
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    • 2002
  • In this presentation, the methods that is appropriate to remediate the farmland contaminated by petroleum hydrocarbon was considered using the case histories of the abroad. As a result of a consideration, most remediation procedures were based risk assessment and management, risk-based procedure. It is also useful to use natural attenuation mechanism to remediate petroleum-contaminated sites. However, more research efforts are demanded for developing a cost-effective and efficient technologies.

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구조물의 붕괴에 대한 사례연구 (Case Histories and the Study of Structural Failures)

  • 정영수
    • 콘크리트학회지
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    • 제8권3호
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    • pp.84-92
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    • 1996
  • 구조물 붕괴사례에 대한 연구는 항상 공학관련 문헌에 한 부분이 되어 왔으나 교량기술의 향상에 기여할 수 있었던 1840년대와 1930년대 사이에 발생했던 여러 붕괴사례들은 기술혁신이 진행되면서 큰 관심사는 되지 못했던 것 같다. 끊임없이 향상되었던 해석이론 및 구조적 규모면에서 커다란 도약을 성취하였떤 이 시대에도 몇몇 중요한 교량 붕괴사례를 목격하였다. 특히 Tacoma Narrow Bridge의 붕괴가 발생한 후 구조물 붕괴사례에 대한 연구는 구조설계와 시공분야에서 공학적인 통찰력과 판단력을 위한 중요한 자료로 인식되어지게 되었다.