• Journal of Chest Surgery
• /
• v.39 no.10 s.267
• /
• pp.770-774
• /
• 2006

Background: Continuous air leakage through chest tube after lung surgery may increase pt's hospital stay and lead to many complications including empyema etc. Chemical pleurodesis has frequently been used for prevention of air leakage. Therefore, we performed chemical pleurodesis using diluted fibrin glue in patients with continuous air leak-age and observed the effects and efficiency of treatment. Material and Method: From September, 2001 to August, 2005, 16 patients whose continuous air leakage lasted more than 7 days underwent chemical pleurodesis with diluted fibrin glue. The effects of treatment, complications and recurrences were reviewed. Dissolved fibrinogen 1.0 g and aprotinin 500,000 KIU were mixed in a 50 cc syringe (Mixed solution A). And dissolved thrombin 5,000 IU and Calcium chloride 600 mg were mixed in a 50 cc syringe (Mixed solution B). Cefazolin 1.0 g was mixed in a 50 cc syringe (Mixed solution C). Rubber tube was inserted between the chest tube and the collecting bottle. An inserted rubber tube was positioned 60cm above the patient and forming a loop appearance was done. Mixed solutions A, B and C were injected into the highest rubber tube. Results: Continuous air leakages disappeared in all f6 patients at next day. Chest tubes were removed after 3 days in all patients. Complications were chest pain in 12 patients (75%), leukocytosis in 14 patients (88%), fever and chill in 14 patients (88%). All complications were transient and disappeared without specific treatment. Conclusion: Our findings demonstrated that diluted fibrin glue chemical pleurodesis was effective in patients with continuous air leakage lasting more than 7 days. Diluted fibrin glue chemical pleurodesis had good results with acceptable complications. long term follow-up is necessary to evaluate the accurate effects of treatment and recurrence in a large number of patients.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
• /
• 2011.11a
• /
• pp.218-221
• /
• 2011

원자력발전소 화재방호는 소방법령에서 요구하는 인명안전 및 재산보호에 대한 요건이외에도 원자력법령에서 요구하고 있는 원자로의 안전정지 및 방사성물질 누출제한에 대한 요건을 만족시켜야 한다. 본 논문에서는 소방시설에 대한 소방법령 적용시 문제점과 현재 원전에 대한 화재방호 규제현황에 대하여 소개하고 원전 화재안전성 향상을 위한 규제방향을 제시하고자 한다.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.53 no.9
• /
• pp.118-125
• /
• 2016

Rotating modulation collimator(RMC) is a remote sensing technique for a radiation source. This paper introduces an RMC system model and its image reconstruction algorithm based on Kowash's research. The reconstructed image can show the direction of a source. However, the distance to the source cannot be recovered. Moreover, the RMC image suffers from $180^{\circ}$ ambiguity. In this paper, we propose a distance estimation method using two RMCs together with a solution to the ambiguity. We also demonstrate its performance using simulated RMC data.

• Journal of Chest Surgery
• /
• v.29 no.4
• /
• pp.444-448
• /
• 1996

Hemolytic anemia due to tiny prosthetic paravalvular leakage is one of a complication of prosthetic valve replacement. Mild Hemolysls usually occurs after aortic valve replacement with mechanical valve but rarely occurs in mitral valve position especially in case of tissue valve. Cardiac valves fabricated from biologic material are associated with a reduced incidence of hemolytic anemia. Hemolysis was reported in patients with an lonescu-Shiley bovine pericardial xenograft prosthesis in the aortic position but not in the mitral site. A 41-year-old female patient was admitted due to sudden development dark colored urine. About 10 years ago the patient was underwent MVR (Mitral Valve Re lacement) with fTmm lonescu-Shiley valve due to MR (Mitral regurgitation). Echocardiographic examination showed mild degree of mitral regurgitation with valvular thickening. However, there was no definitive evidence of paravalvular leakage. The peripheral blood smear showed nomochromic normocytic anemia, but the hematologic and urinary examination revealed severe hemolytic evidence. Mitral valve replacement with St. Jude Medical valve (27mm) was done and intraoperatively, a tiny paravalvular leakage was found which was regarded as the point of hemolysis. The hemolytic evidence completely disappeared. We are reporting a case of severe hemolytic anemia due to tiny prosthetic paravalvular leakage with a review of the literature.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.33 no.2
• /
• pp.192-200
• /
• 2006

The aim of this study was to assess the microleakage underneath a pit and fissure sealant bonded to occlusal surfaces treated by Er:YAG laser To determine the most effective energy density of laser, fourteen specimens were irradiated from 50mJ to 300mJ at 3Hz. After irradiation, the lased specimens were observed under the scanning electron microscope. Thirty six non-carious extracted premolars were randomly assigned to four groups of nine teeth: group 1, no treatment on the occlusal surface; group 2, acid etching for 15 seconds; group 3, Er:YAG laser irradiation; group 4, acid etching followed by Er:YAG laser irradiation. The pits and fissures were sealed with unfilled sealant(Helioseal F) and the specimen teeth were thermo-cycled, immersed in 2% Rhodamine B solution, longitudinally sectioned and analyzed for microleakage with fluorescent microscope. The results were as follows: 1. Er:YAG lased surfaces with 50mJ, 3Hz showed a similar pattern of irregularity with acid etched enamel surfaces 2. The mean microleakage score increased in the order of group 2, 4, 3 and 1. There was no significant difference among group 1, 3 and 4(p>0.05), however group 2 showed significantly less microleakage compared with group 1 and 3. Conclusively, the laser irradiation seemed not enough to replace the acid etching for proper retention of pit and fissure sealants.

• Restorative Dentistry and Endodontics
• /
• v.34 no.6
• /
• pp.484-490
• /
• 2009

The purpose of this study was to evaluate the effect of soft chelating irrigant on the sealing ability of root fillings by using a glucose leakage test. A total of 45 single-rooted teeth were selected for the study. The teeth were decoronated leaving a total length of 13mm. The root canals prepared using K3 NiTi rotary instruments to an apical dimension of size 45(0.06 taper). The specimens were then randomly divided into 3 experimental groups of 13 roots each and 2 control groups of 3 roots each. Specimen in each group were prepared with different irrigation protocols : group 1, 2.5% NaOCl; group 2, 2.5% NaOCl and 17% EDTA: group 3, 2.5% NaOCl and 15% HEBP. The root canals were filled with gutta-percha and AH Plus sealer using lateral condensation. After 7 days in $37^{\circ}C$, 100% humidity, the coronal-to-apical microleakage was evaluated quantitatively using a glucose leakage model. The leaked glucose concentration was measured with spectrophotometry at 1, 4, 7, 14, 21 and 28 days. There was a tendency of increase in leakage in all experimental groups during experimental period. HEBP-treated dentin showed no significant difference with EDTA-treated dentin during experimental period. From the 21th day onward, HEBP-treated dentin showed significantly lower leakage than smear-covered dentin. HEBP-treated dentin displayed a similar sealing pattern to EDTA-treated dentin and a better sealing ability than smear-covered dentin. Consequently, a soft chelator(HEBP) could be considered as the possible alternative to EDTA.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.32 no.1
• /
• pp.164-173
• /
• 2005

Mechanical preparation has been introduced to provide the sealant retention. The objective of this study was to compare the fissure penetration and the microleakage of pit and fissure sealant using mechanical preparation(mechanical preparation + acid etching) and acid etching only. An additional objective of this study was to compare the fissure penetration and the microleakage of unfilled and filled sealant in both methods. Sixty human premolars extracted for orthodontic purpose were selected. Thirty teeth were acid etched alone and remaining thirty teeth were prepared with a $\frac{1}{4}$ round bur and then acid etched. One-half of teeth in each surface treatment method were sealed with unfilled sealant and the other half were sealed with filled sealant. All of the teeth were thermocycled for 1200 cycles at $5^{\circ}C\;and\;55^{\circ}C$ and immersed in 5% methylene blue for 24 hours. Each tooth was sectioned bucco-lingually at mesial pit and distal pit and examined under a Measurescope. In the case of mechanical preparation, fissure penetration of sealant was significantly increased compared with the case of acid etching only(P < 0.05). The filled and unfilled sealant using mechanical preparation showed significantly decreased microleakage when compared with the unfilled sealant using acid etching only(P < 0.05). No differences were found in fissure penetration and microleakage between unfilled and filled sealant in both methods. Taken together, the results of this study suggest that mechanical preparation and filled sealant are recommended when placing pit and fissure sealant. However, further clinical studies should be performed in regard to microleakage.

• Journal of the Korean Institute of Gas
• /
• v.16 no.6
• /
• pp.29-33
• /
• 2012

This paper is an attempt to give a concise overview of the state-of-the-art in the recent liquid hydrogen safety researches with unwanted event progress. The vessel of liquified hydrogen may fail and liquid hydrogen spilled. The hydrogen will immediately start to evaporate above a pool and make a hydrogen cloud. The cloud will disperse and can produce a vapor cloud explosion. The vessel containing the liquid hydrogen may not be able to cope with the boil-off due to heat influx, especially in case of a fire, and a BLEVE may occur. In equipment where it exists as compressed gas, a leak generates a jet of gas that can self-ignite immediately or after a short delay and produce a jet flame, or in case it ignites at a source a certain distance from the leak (delayed ignition), a flash fire occurs in the open and with confinement a deflagration or even detonation may develop. The up-to-date knowledge in these events, recent progress and future research are discussed in brief.

• Proceedings of the KIEE Conference
• /
• 2006.04a
• /
• pp.324-326
• /
• 2006

CCD형 영상소자는 방사선 피폭 시 표면과 격자내부에 모두 손상을 받게 되며, 감마방사선이나 X선과 같은 고에너지의 이온화 방사선에 노출될 경우 격자 실리콘 내부에 전자-전공쌍(Electron-hole pair, EHP)이 발생된다. 이러한 EHP는 CCD의 순간 출력 광전류로 변환되어 백색 화소 형태의 영상잡음으로 가시화되며, 이 화소 수는 피폭 방사선량에 비례하여 증가하는 특성을 지니고 있다. 따라서 출력 영상정보를 분석하면 조사된 방사선의 양과 특성을 측정할 수 있다. 본 연구에서는 CCD를 이용하여 가상의 방사능 물질 누출 공간에서 방사선원의 방향과 거리정보를 고속으로 탐지하기 위한 장치와 고속 측정 알고리즘을 구현하고 실제 방사선장에서 실증시험을 수행하였다. 방사선 탐지기는 콘형 납 콜리메이터(Collimator)와 가시광 변환용 신틸레이터(CsITl) 및 차폐체로 구성된 센서부와 제어 및 방사광 신호처리를 수행하는 PC부로 구성된다. 감마방사선($^{60}Co$) 방사선장 실증시험에서 방사선원간 거리 83cm에서 측정된 거리 탐지는 5.3%의 오차로 확인되었다. 이 방사선 탐지기는 임의의 고방사선 누출사고에 대한 초기대응 작업을 수행하기 위한 무인 이동로봇용 방사선 탐지기로 활용이 가능하다.

• Journal of the Korean Institute of Gas
• /
• v.13 no.2
• /
• pp.49-56
• /
• 2009

This thesis suggests ways for ensuring the safety of domestic autogas (liquefied petroleum gas) vehicles by conducting comparison and analysis on the status of market diffusion and safety management scheme in foreign countries as well as in Korea. According to the result of the survey on the status of domestic autogas safety management, the national scheme to secure the safety of autogas vehicles seems neither well-organized nor sufficiently-controlled. Actually, the gas leakage check-ups conducted for 5,000 autogas cars revealed that about 4 percent of them had leakage problems. As a result, it was acknowledged that the autogas safety regulations being operated in advanced countries need to be selectively introduced for the domestic autogas industry. Consequently, in line with the recent permission to use autogas as a fuel for subcompact cars etc., this thesis is recommending some methods to enhance the safety management scheme for autogas cars such as the amendment of facility regulations including the ventilation of underground parking lots, mandatory attachment of labels claiming autogas cars and indicating periodical inspections etc.