• 제목/요약/키워드: Leak sites

검색결과 34건 처리시간 0.024초

반면형 방진마스크의 누출부위 분포조사 (Identification and Distribution of Leak Sites of Half Mask Respirators)

  • 허지연;김현욱
    • 한국산업보건학회지
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    • 제4권2호
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    • pp.180-188
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    • 1994
  • This study was designed to investigate qualitatively whether respirators now being used in workplaces tit workers iflfaces well or not. Leak sites were determined after exposing the subjects to fluorescent aerosol and were analyzed by gender, brand and manufacturing nation. The results were as follows ; 1. Among those leak sites which were classified into four areas(nose, cheek, lip and chin), test aerosol was mostly deposited on the nose and the cheek areas. 2. The mean number of leak sites observed from the female subjects were 2.3 while the number were 2.2 from the male subjects. The most frequently observed leak site was nose and followed by chin, lip and cheek in descending order of frequency. 3. Among different brands of respirators, different leak sites were observed. Test subjects wearing the Sand N brands were more heavily exposed than those of wearing the D and M brands. 4. No significant difference of the number of leak sites were found between Korean-made and American-made masks. However, the most frequent leak site observed for the Korean-made ones was the nose area while it was the chin area for the American-made ones. 5. Analyses of 97 leak sites by shape showed that 27(27.8%) were point types, 54(55.7%) diffuse types and 16(16.5%) streamline types. 6. Test subjects indicated that the facepieces of Korean-made respirators were harder and smaller in size than those of American-made one. The most comfortable respirator selected was the respirator by the N Co. and the most uncomfortable one was the respirator by the D Co. This study suggests that many half-mask respirators now being used in the workplaces may not fit to workers well. Therefore, when selecting respirators, employers are advised to test respirators if they fit to workers well. And manufacturers are recommended to produce effective and comfortable respirators tested qualitatively and quantitatively not only in the laboratory but also in the field.

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음향방출 및 상관법을 이용한 상수도배관 누수탐지 연구 (Leak Detection of Waterworks Pipeline Using Acoustic Emission and Correlation Method)

  • 윤동진;정중채;이영섭
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.84-89
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    • 2003
  • Water leak is one of topics with great concern in Korea and many other countries, because of decreasing water supplies and the deterioration of old pipeworks. Correlation techniques have been widely used in leak detection of water pipes, which allow to locate a leak point based on the correlation of leak noise at two sites along water pipes. In this study, both the cross-correlation method and the conventional arrival time difference method are applied in order to analyze and to locate a leak point of a water pipe. In experiment, a 150 m of whole length waterwork pipeline system was constructed in a ground, and several types of leak noise were installed on the pipeline in order to control leak condition. Both the cross-correlation technique and the arrival time difference method showed favorable results at leak detection with the experimental pipeline system.

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양자기술기반 가스 누출 감지 시스템 개발 (Development of Gas Leak Detecting System Based on Quantum Technology)

  • 권오성;박민영;반창우
    • 한국가스학회지
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    • 제25권5호
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    • pp.57-62
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    • 2021
  • 가스는 일반 가정 및 산업현장에서 폭 넓게 사용되는 에너지원이기도 하고, 석유화학 및 반도체 공정에서 넓게 사용되는 공정 물질이기도 하다. 그러나 사용이 쉬운 반면에 누출 시, 폭발 및 인체흡입 등으로 대규모 인명피해를 발생시키기도 한다. 따라서 가정 및 산업현장에서 안심하고 사용할 수 있는 가스 시설물 안전관리 솔루션은 필수적이다. 특히 가스시설의 노후화에 따라 고도화된 가스안전 솔루션의 개발 필요성이 대두되고 있는 실정이다. 본 논문은 가스 시설물에 더 이상 나눌 수 없는 최소 에너지 단위인 광자를 조사하고, 반사된 광자의 수를 분석해 원거리에서 가스 누출 여부 및 농도를 측정하는 기술을 개발하였다. 이는 기존의 전기/화학식 가스 센서나 적외선 기반의 가스 누출 감지기의 한계인 짧은 탐지 거리, 미세 누출 감지 불가 등의 기술적 한계를 극복하였다.

Traumatic cerebrospinal fluid leakage following septorhinoplasty

  • Youssef, Ahmed;Ahmed, Shahzad;Ibrahim, Ahmed Aly;Daniel, Mulvihill;Abdelfattah, Hisham M.;Morsi, Haitham
    • Archives of Plastic Surgery
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    • 제45권4호
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    • pp.379-383
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    • 2018
  • Septoplasty/septorhinoplasty is a common ear, nose and throat procedure offered for those patients with deviated septum who are suffering from nasal obstruction and functional or cosmetic problems. Although it is a basic and simple procedure, it could lead to catastrophic complications including major skull base injuries which result in cerebrospinal fluid (CSF) leaks. We describe two different cases of traumatic CSF leaks following septoplasty/septorhinoplasty at two different sites. The first patient suffered a CSF leak following septoplasty and presented to Alexandria University Hospital. The leak was still active at presentation and identified as coming from a defect in the roof of the sphenoid sinus and was repaired surgically. The second patient presented 4 days after her cosmetic septorhinoplasty with a CSF leak and significant pneumocephalus. She was managed conservatively. Understanding the anatomical variations of the paranasal sinuses and implementing proper surgical techniques are crucial in preventing intracranial complications when performing either septoplasty or septorhinoplasty. A good quality computed tomography of the nose and paranasal sinuses is a valuable investigation to avoid major complications especially CSF leaks following either procedure.

다크웹 환경에서 산업기술 유출 탐지 시스템 (Industrial Technology Leak Detection System on the Dark Web)

  • 공영재;장항배
    • 스마트미디어저널
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    • 제11권10호
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    • pp.46-53
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    • 2022
  • 오늘날 4차 산업 혁명과 대규모 R&D 지원으로 인해 국내 기업은 세계 기술력 수준의 산업기술을 보유하기 시작하였으며 중요한 자산으로 변모하였다. 국가는 기업의 중요한 산업기술을 보호하고자 국가핵심기술로 지정하였으며, 특히 원자력, 조선, 반도체와 같은 기술이 유출될 경우 해당 기업뿐만 아니라 국가 차원에서도 심각한 경쟁력 손실로 이어질 수 있다. 매년 내부자 유출, 랜섬웨어 그룹의 해킹공격, 산업스파이에 산업기술 탈취 시도가 증가하고 있으며, 탈취된 산업기술은 다크웹 환경에서의 은밀하게 거래가 이루어진다. 본 논문에서는 다크웹 환경에서 은밀하게 이루어지는 산업기술 유출을 탐지하는 시스템을 제안한다. 제안된 모델은 먼저 OSINT 환경에서 수집한 정보를 이용하여 다크웹 크롤링을 통한 데이터베이스를 구축한다. 이후 KeyBERT 모델을 이용한 산업기술 유출 키워드를 추출한 후 다크웹 환경에서의 산업기술 유출 징후를 정량적 수치로 제안한다. 마지막으로 식별된 다크웹 환경에서의 산업기술 유출 사이트를 기반으로 PageRank 알고리즘 통한 2차 유출 가능성을 탐지한다. 제안된 모델을 통해 27,317개의 중복 없는 다크웹 사이트를 수집하였으며, 100개의 원자력 특허에서 총 15,028개의 원자력 관련 키워드를 추출하였다. 가장 높은 원자력 유출 다크웹 사이트를 기반으로 2차 유출을 탐지한 결과 12개의 다크웹 사이트를 식별하였다.

Outcomes and predictors of response to endotherapy in pancreatic ductal disruptions with refractory internal and high-output external fistulae

  • Sridhar Sundaram;Biswa Ranjan Patra;Dhaval Choksi;Suprabhat Giri;Aditya Kale;Nitin Ramani;Abhijeet Karad;Akash Shukla
    • 한국간담췌외과학회지
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    • 제26권4호
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    • pp.347-354
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    • 2022
  • Backgrounds/Aims: Endoscopic retrograde cholangiopancreatography (ERCP) remains the primary treatment for a subset of patients with pancreatic fistulae. The objective of this study was reporting outcomes of ERCP and predictors of resolution in patients with pancreatic fistulae refractory to conservative therapy. Methods: Retrospective review of patients who underwent ERCP and pancreatic stent placement for pancreatic fistula not responding to medical therapy was performed. Clinical features, laboratory parameters, radiological features and pancreatogram findings were noted. Clinical resolution of fistula was the primary outcome measure. Results: Sixty-eight patients underwent ERCP for high-output pancreatic fistula (Mean age 34.1 years, 91.1% males, 35/68 chronic pancreatitis, 52.9% alcohol etiology). Internal fistulae (pancreatic ascites, pleural effusion, or pericardial effusion) were seen in 55 (80.9%) patients and external fistula in 13 (19.1%) patients. Technical success for ERCP was 92.6% (63/68). Leak was seen in 98.4% (62/63). The most common leak site was body (69.8%). Multiple leak sites were seen in 23.1%. Pancreatic stricture was found in 36.5%. In 44 (69.4%) patients, stent was placed beyond the site of the leak. Resolution at six weeks was achieved in 76.4% (52/68). On univariate and multivariate analyses, placement of stent beyond site of leak was significantly associated with resolution of high-output fistulae (3/41 [7.3%] vs. 5/19 [26.3%], p = 0.03; odds ratio: 6.5, 95% confidence interval: 1.211-34.94). Conclusions: In our experience, ERCP was successful in 76% of patients with pancreatic fistulae refractory to conservative therapy. Stent placement beyond the site of leak was associated with higher resolution of fistulae.

매몰지 생물반응조 개조를 통한 사체의 안정화 촉진 (Enhanced Stabilization of Carcasses by Retrofitting Burial Sites to Bioreactor)

  • 김건하;전해성
    • 대한환경공학회지
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    • 제36권10호
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    • pp.679-684
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    • 2014
  • 가축전염병 확산을 방지하기 위하여 조성된 긴급매몰지의 경우 침출수 누출이 확인되면 원형저장조로 이설된 경우가 있는데, 저장조 내 낮은 함수율과 혼합문제로 인해 분해가 거의 이루어지지 않고 있는 실정이다. 본 연구에서는 사체의 안정화를 촉진할 수 있도록 원형저장조를 생물반응조(Bioreactor)로 구조를 변경하였다. 침출수를 재순환하고 미생물을 공급하여 안정화에 필요한 미생물활동을 증가시켰다. 원형저장조 내부 유기물의 변형을 고려한 침하량 모형을 사용하여 예측한 침하량 최종치는 생물저장조 구조 변경 후 5년간 약 30%이었다.

Characteristics of AE Signals from Fatigue Crack Propagation and Penetration of a Surface Crack in 6061 Aluminum Plate

  • Ahn, Seok-Hwan;Nam, Ki-Woo
    • International Journal of Ocean Engineering and Technology Speciallssue:Selected Papers
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    • 제4권1호
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    • pp.44-50
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    • 2001
  • Existing surface defects in structural members often act as sites of fatigue crack initiation, and if undetected, these cracks may grow through the thickness of the member, leading to catastrophic failure of the structure. Thus, in-service monitoring of fatigue cracks through reliable and effective nondestructive techniques is an important ingredient in the leak-before-break (LBB) design and safe operation of defects critical structures. An advanced, waveform-based, acoustic emission (AE) technique has been used in this paper to study the characteristics of the signals emanating from the initiation, growth and through-the -thickness penetration of surface fatigue crack in a 6061 aluminum plate. The goal of this experimental study is to determine whether the evolution of the fatigue crocks could be identified from the properties of the waveforms produced during the tests. The AE waveform signals detected at different stages of crack growth was found to have different temporal and spectral characteristics. The data analysis technique presented here can be applied to real-time monitoring of the initiation and propagation of fatigue cracks in structural components.

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안전모 장착용 가스 누출 경보 IoT 시스템 설계 및 구현 (Design and Implementation of Gas Leakage Alarm IoT System for Safety Helmet)

  • 주용민;이효승;오재철
    • 한국전자통신학회논문지
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    • 제13권6호
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    • pp.1411-1416
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    • 2018
  • 현재 화학, 제조, 조선, 철강 등 대부분의 공업 지역에서는 가스와 관련된 작업을 진행하게 되는데 이러한 작업을 수행하는 담당자의 경우 가스 누출 등의 사고를 인지하지 못하고 질식하는 등의 위험을 안고 작업을 진행하게 된다. 그 예로 2015년 파주에서 질소 가스가 누출돼 2명이 사망하고 4명이 부상을 당하였고 2018년에는 포항에서 4명의 근로자가 질소가스에 질식하여 사망하는 사고가 발생하였다. 이러한 문제를 해결하고자 본 연구에서는 현장 작업자가 필수로 착용하여야 하는 안전모에 가스 센서와 통신모듈 등으로 구성된 IoT 장치를 장착하여 작업자가 가스의 누출을 즉각적으로 인지함과 동시에 안전담당자에게 상황을 전달할 수 있는 시스템을 구현하여 이를 통해 산업 현장에서 가스 누출에 대한 인명사고를 줄일 수 있기를 기대한다.

수술용 장갑의 천공률에 대한 연구 (Incidence and Risk Factors for Surgical Glove Perforation)

  • 유선주;임영신;김명숙
    • 임상간호연구
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    • 제16권3호
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    • pp.63-71
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    • 2010
  • Purpose: This study was conducted to evaluate the incidence and risk factors for surgical glove perforation during operation. Methods: During the month of december 2008, a total of 1,400 pairs of surgical gloves used in major operations was collected in a tertiary hospital. All gloves were examined immediately after operation using the standardized water-leak method to detect any perforation. Incidence of the glove perforation was counted according to the type of operation, operation time, the number of involved personnel, perforation sites, and the manufacturing companies. Results: Out of 2,800 gloves examined, 312 perforations were detected comprising 11.1% of samples. In terms of the type of operation, the perforation incidence varied from 5% to 20%, and the perforation rates in CS (20%) and NS (18%) (p<.001) were significantly higher than those in other departments. The 1st assistant or scrub nurse got glove perforation more frequently than the 2nd assistant or operator (p<.001). Longer operation time was associated with higher incidence of perforation evidently (p<.001). In terms of the sites, the thumb and index finger were more frequently perforated than other sites (4.1% and 3.4% respectively) without any differences between left and right side. Conclusion: Risk factors for glove perforation including the department of operation, operation time, participating personnel, and location of perforation should be taken into account to improve surgical safety.