• 제목/요약/키워드: Leaks

검색결과 450건 처리시간 0.022초

폐기물 매립지 차수층 누출시 전기영동 복원을 위한 침출수에서의 향상기법 (The Enhanced Electrophoresis Method in Leachate System for Repairing of Leaks in Waste Landfill Geomembrane Liner)

  • 김종윤;한상재;김수삼
    • 대한토목학회논문집
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    • 제30권1C호
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    • pp.7-15
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    • 2010
  • 폐기물 매립지에서 손상된 지오멤브레인 라이너에 의해 지층으로 오염물질의 침투가 유발된 경우, 환경적인 피해를 최소화 하기 위해서는 전기영동기법에 의한 지오멤브레인 라이너의 즉각적인 복구가 필요하다. 하지만 실제 매립장 침출수내에서 전기영동기법 적용시 침출수내 다양한 화학종과 점토입자와의 상호작용으로 인해 점토 입자들의 응집이 촉진되고, 전기영동적 이동보다 중력에 의한 침강거동이 우세하게 나타나며, 결국 실제 매립지 현장에 대한 전기영동기법의 적용상 한계점이 유발되었다. 이에 따라 본 연구에서는 점토입자의 응집을 최대한 방지시켜 전기영동력에 의한 입자의 개별적 이동이 유발될 수 있도록 전기영동 향상기법에 대한 1차원 실내실험을 수행하였다. 그 결과, PAA를 사용할 경우, 점토 끝단에 흡착된 폴리머의 전기적 척력효과로 인해 점토 입자의 분산화 효과가 증대되었다.

광분광기의 노이즈 감소를 위한 암전류에 대한 실험적 고찰 (Experimental Study on Dark Current Noise to Reduce Background Voltage Level of Optical Emission Spectroscopy)

  • 육영준;이건우;최은종;김효영;김기현
    • 반도체디스플레이기술학회지
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    • 제22권4호
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    • pp.93-98
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    • 2023
  • As semiconductor devices become highly integrated and process difficulty increases, the need for highly sensitive sensors that can detect micro leaks is increasing. However, the noise contained in the CCD sensor itself acts as an obstacle to detecting fine leaks. In this study, integration time was changed for each condition, the sensor was cooled to 0℃, and the dark voltage level was measured to confirm through experiment the characteristics of the temporal noise included in the CCD sensor, a component of OES (Optical Emission Spectroscopy). When integration time was reduced from 30msec to 10msec, the dark voltage level decreased by about 20.5 % from an average of 151.5mV to 120.5mV. In the case of cooling device, Peltier elements were selected because of their simple structure and small size. During temperature cooling, the target temperature was controlled to within ±0.5℃ through PID control. When cooled from 20℃ to 0℃ using this cooling device, it was confirmed that the dark voltage level decreased by about 7% from an average of 147.0mV to 137.0mV.

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Endoscopic Intervention for Anastomotic Leakage After Gastrectomy

  • Ji Yoon Kim;Hyunsoo Chung
    • Journal of Gastric Cancer
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    • 제24권1호
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    • pp.108-121
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    • 2024
  • Anastomotic leaks and fistulas are significant complications of gastric surgery that potentially lead to increased postoperative morbidity and mortality. Surgical intervention is reserved for cases with severe symptoms or hemodynamic instability; however, surgery carries a higher risk of complications. With advancements in endoscopic treatment options, endoscopic approaches have emerged as the primary choice for managing these complications. Endoscopic clipping is a traditional method comprising 2 main categories: through-the-scope clips and over-the-scope clips. Through-the-scope clips are user friendly and adaptable to various clinical scenarios, whereas over-the-scope clips can close larger defects. Another promising approach is endoscopic stent insertion, which has shown a high success rate for leak closure, although vigilant monitoring is required to monitor stent migration. Infection control is essential in post-surgical leakage cases, and endoscopic internal drainage provides a relatively safe and noninvasive means to manage fluids, contributing to infection control and wound healing promotion. Endoscopic suturing offers full-thickness wound closure, but requires additional training and endoscopic versatility. As a promising tool, endoscopic vacuum therapy potentially surpasses stent therapy by draining inflammatory materials and closing defects. Furthermore, the use of tissue sealants, such as fibrin glue and cyanoacrylate, has been reported to be effective in selected situations. The choice of endoscopic device should be tailored to individual cases and specific patient conditions, with careful consideration of the nature of the defect. Further extensive studies involving larger patient populations are required to provide more robust evidence on the efficacy of endoscopic approach in managing post-gastric anastomotic leaks.

폴리우레아 도막방수재의 이음부 적정 시공안 제안을 위한 성능 분석 (Performance Analysis for Proposing Proper Construction Method for Joints of Polyurea Waterproofing Membrane Coating)

  • 이정훈;김병일
    • 한국건축시공학회지
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    • 제24권1호
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    • pp.77-86
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    • 2024
  • 본 연구에서는 폴리우레아 도막방수재의 시공 시차별 분석과 열화면에 대한 유지관리 시공 타입별 분석을 통해 시공 이음부위의 적정 시공 방안을 제시하고자 전체 16가지 조건을 대상으로 시공 이음부위에 대한 평가를 진행하였다. 결과 분석을 통해 시공시차가 길어지면 길어질수록 이음부를 통한 누수발생률은 증가하는 것으로 분석되었고, 프라이머 시공을 통해 누수 예방이 가능한 것으로 확인되었다. 또한 장시간 옥외 노출된 폴리우레아는 표면이 열화되어 약해진 상태이기 때문에 해당 부위를 연마할 경우 표면손상이 확대되어 계면 형성에 영향을 미치는 것으로 분석되어, 유지관리 시공 시에는 프라이머를 도포하고 시공하는 것이 바람직하겠으며, 동일한 우레아 계열의 재료를 시공하는 것이 방수 안정성을 확보할 수 있을 것으로 판단된다.

예방 기능을 갖춘 스마트폰 분실방지 애플리케이션의 설계 및 구현 (Design and Implementation of a Smartphone Application for Loss Prevention with Precautionary Functions)

  • 고정국
    • 한국멀티미디어학회논문지
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    • 제17권9호
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    • pp.1098-1103
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    • 2014
  • Smartphone is very much ingrained into our lives and it has propagated rapidly. With the growing expansion of smartphone, the number of lost smartphones has proliferated all the while. Unlike common personal belongings, smartphone is a high-priced goods and has personal information. In case it gets lost or stolen, it will cause monetary damage as well as secondary damage of personal information leaks. To lesson the damage, diverse applications that prevent the loss of a smartphone have been developed. But existing applications place emphasis on providing countermeasures that tracks the missing smartphones. Therefore, this paper describes the design and implementation of a smartphone application which provides precautionary functions to prevent the loss of a smartphone and countermeasures to track the missing smartphone. The implemented application prevents the loss of a smartphone using satefy zone and movement detection. In the event we lose a smartphone, it helps us recover a lost property using location tracking and remote control functions quickly and efficiently.

인제군의 상수관로 개량을 위한 주민의 지불의사금액 추정 (Estimation of Willlingness-to-pay of Residents for Rehabilitation of the Existing Water Pipes at Inche)

  • 이재훈;정동환;신승복;박규홍
    • 상하수도학회지
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    • 제21권4호
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    • pp.385-394
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    • 2007
  • The objective of this study was to estimate social cost on rehabilitation of existing water pipes by investigating the willingness-to-pay (WTP) of residents at INJE County to avoid the loss and inconvenience of transportation and business resulting from the sudden failure and leaks of old water pipes. Contingent valuation method was used through conducting survey to 180 residents in Inche County, with questions of double-bounded dichotomous choice. The resulting WTP of residents at Inche was 7,682 won/month/household. The annual social cost could be estimated as 960 million won, which might be caused by the failure of the old water pipes at INJE County.

래이디얼 피스톤 펌프의 효율 특성 연구 (A Characteristic Study of Efficiency in Radial Piston Pump)

  • 장윤석;천세민;임윤철
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 2000년도 제31회 춘계학술대회
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    • pp.106-113
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    • 2000
  • A pump which is a fundamental device in a hydraulic system affects on overall system performance to a great deal. Such problems as leakage and solid friction loss become important in field applications, especially for the case of operation under high pressure and at high speed. So the research on this kind of subjects is necessary to improve the performance of hydraulic devices. A high pressure radial piston pump is analyzed here, which has a stationary cylinder block. It pumps hydraulic fluid by letting camring push a piston in a cylinder. Fluid leaks between the piston and cylinder so that it deteriorates the pump efficiency. Furthermore, the piston happens to touch the cylinder wall to increase the friction loss and wear. In this research, by means of FDM, volumetric, mechanical and overall efficiencies are observed by varying several design Parameters and operation conditions. Design values or their trends are presented to improve these efficiencies.

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철도 차량기지내 비점오염물 처리방안 연구 (A Study on Disposal Method of Non-Point Pollutant of the Rolling Stock Depot)

  • 정재형;신민호;조국환
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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    • pp.2910-2916
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    • 2011
  • Environmental conservation is becoming the major conversation topic in the 21st century, the era of environment. In the Law for the Preservation of Water Quality, article 53 states "A business unit which is doing business causing pollution caused by non-point pollutant or builds waste water discharge facilities, should report the installation of the non-point pollutant and install the required pollution control facilities". Environmental pollution caused by oil leaks during operation or maintenance has been found in the railway sector. Especially, rolling stock depot is most likely to be affected by environmental pollution. Therefore, in this paper We have investigated non-point pollutant in the rolling stock depot area and have studied adequate disposal method to minimize the effect of the non-point pollutant, hoping to supply the preliminary data for building an environment-friendly rolling stock depot.

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안드로이드 애플리케이션의 협력적인 개인 정보 유출 탐지 (Detecting Collaborative Privacy Information Leaks on Android Applications)

  • 전철;조유근;홍지만
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2012년도 한국컴퓨터종합학술대회논문집 Vol.39 No.1(A)
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    • pp.92-94
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    • 2012
  • 안드로이드 운영체제는 애플리케이션들이 서로의 코드와 데이터를 공유할 수 있도록 애플리케이션 컴포넌트간의 통신을 지원한다. 또한 보안을 위해 컴포넌트간의 통신을 엄격하게 제어하기 위한 퍼미션을 제공한다. 하지만 개발자의 보안의식 부재에 따른 퍼미션의 잘못된 사용은 애플리케이션 컴포넌트를 노출시켜 검증되지 않은 애플리케이션이 코드와 데이터에 접근할 수 있게 만드는 문제를 야기할 수 있다. 특히, 노출된 컨텐트 프로바이더(content provider)는 악성 애플리케이션이 기존 탐지 툴을 회피하여 개인정보를 임시로 보관하는 저장소로 악용될 수 있다. 따라서 하나의 애플리케이션만을 분석하는 기존 탐지 툴로는 이와 같이 협력적으로 동작하는 악성 애플리케이션을 탐지 할 수 없다. 본 논문에서는 노출된 컨텐트 프로바이더를 이용한 협력적 개인정보 유출 공격 시나리오를 제시하고 이를 탐지하기 위한 기법을 제안한다. 제안한 기법을 토대로 만든 탐지 툴 사용해 총 189개의 안드로이드 애플리케이션을 분석하였고 그 결과로 컨텐트 프로바이더를 노출시킨 32개의 애플리케이션과 개인정보를 유출할 가능성이 있는 애플리케이션 4개를 탐지하였다.

On the Application of CFD Codes for Natural Gas Dispersion and Explosion in Gas Fuelled Ship

  • Kim, Ki-Pyoung;Kang, Ho-Keun;Choung, Choung-Ho;Park, Jae-Hong
    • Journal of Advanced Marine Engineering and Technology
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    • 제35권7호
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    • pp.946-956
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    • 2011
  • The main objectives of this study are to analyze the leaked gas dispersion and quantify the potential overpressures due to vapor cloud explosions in order to identify the most significant contributors to risk by using Computational Fluid Dynamics (CFX & FLACS) for gas fuelled ships. A series of CFD simulations and analyses have been performed for the various gas release scenarios in a closed module, covering different release rates and ventilating methods. This study is specially focused on the LNG FGS (Fuel Gas Supply) system recently developed for the propulsion of VLCC crude oil carriers by shipyards. Most of work presented is discussed on the gas dispersion from leaks in the FGS room, and shows some blast prediction validation examples.