• Nuclear Engineering and Technology
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• 제48권3호
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• pp.642-649
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• 2016

Important safety parameters such as the fuel temperature coefficient (FTC) and the power coefficient of reactivity (PCR) of the CANada Deuterium Uranium (CANDU-6) reactor have been evaluated using the Monte Carlo method. For accurate analysis of the parameters, the Doppler broadening rejection correction scheme was implemented in the MCNPX code to account for the thermal motion of the heavy uranium-238 nucleus in the neutron-U scattering reactions. In this work, a standard fuel lattice has been modeled and the fuel is depleted using MCNPX. The FTC value is evaluated for several burnup points including the mid-burnup representing a near-equilibrium core. The Doppler effect has been evaluated using several cross-section libraries such as ENDF/B-VI.8, ENDF/B-VII.0, JEFF-3.1.1, and JENDL-4.0. The PCR value is also evaluated at mid-burnup conditions to characterize the safety features of an equilibrium CANDU-6 reactor. To improve the reliability of the Monte Carlo calculations, we considered a huge number of neutron histories in this work and the standard deviation of the k-infinity values is only 0.5-1 pcm.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2009년도 춘계 학술논문 발표대회 학계
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• pp.33-39
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• 2009

Asphalt waterproofing method has a long history over 80years since introduce to domestic market. This method has a good point as high water proofing not permeable to water by material performance of bitumen, In spite of high waterproofing, the application has become decreased. This asphalt method has some problem such as work safety, low workability by complicated work process, environmental problem in job site, it should be solve by complementary measures. 'Therefore, in this paper, suggest the principle of high pressure spray by heat cycle type equipment by analysis of exist problem and materials investigation. And. study and examine the spray type degeneration rubberized asphalt membrane materials to adopt job site. Moreover, suggest the evidence by inspection about waterproofing performance by Korean Industrial Standard through the performance test of the spray type degeneration rubberized asphalt membrane materials.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 가을 학술발표회 논문집
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• pp.121-134
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• 2002

Tunneling is a very dangerous and expansive work. Especially, the concrete lining works need many long hours and much cost. As an alternative, the unlined tunneling methods including NMT have been developed in various country. These methods have advantages in cost, time and quality. In Korea, many considerations have been conducted to apply the unlined tunneling method in comparatively good rock. Since primary reinforcements play the role of the final supporting system in unlined tunnels, the initial stiffness and long term durability of reinforcements are very important for tunnel safety. To establish the reinforcements standard suitable to Korea, we investigated the foreign standards and construction cases, comparing geological and construction conditions of foreign land and Korea. As the result, we have proposed the standard of primary supporting system for unlined tunnel in aspects of material, design, construction and quality control etc.

• 한국재난정보학회 논문집
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• 제15권4호
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• pp.607-616
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• 2019

연구목적: 본 연구의 목적은 중·소규모의 사립 박물관을 대상으로 안전관리 업무에 대한 개선을 위하여 매뉴얼을 개발하는 것이다. 연구방법: 현행 사립 박물관의 안전관리에 대한 문제점을 조사하여 위해서 국내에 위치한 50개소의 사립 박물관을 조사대상으로 선정하였다. 그리고 안전관리 업무를 담당하는 실무자들에게 면담과 시설물의 안전점검을 수행하였다. 연구결과: 사립 박물관의 경우 비영리형태의 개인에 의해 운영되고 있으며, 열악한 재정상황 및 박물관 종사자의 안전관리 업무에 대한 비전문성을 보완하기 위해서 안전관리 매뉴얼 작성이 최우선적으로 필요한 것으로 분석되었다. 결론: 중소규모 사립 박물관 종사자의 안전관리 업무에 대한 전문성 향상과 업무의 효율적인 운영을 위해서 그림과 도표를 활용한 시나리오 기반의 표준행동절차 매뉴얼을 제시하였다.

• 한국콘텐츠학회논문지
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• 제21권7호
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• pp.238-247
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• 2021

본 연구는 공공의료기관에 근무하는 간호사의 감염 표준주의지침에 대한 지식, 안전환경, 수행도를 조사하고 표준주의지침에 대한 수행도에 미치는 영향 요인을 확인하기 위한 서술적 조사연구이다. 연구방법은 S시, N시의 2개의 공공의료기관 간호사 192명을 대상으로 설문지를 통해 자료를 수집하였고 SPSS WIN 22.0 통계프로그램을 사용하여 결과를 분석하였다. 연구결과 표준주의지침 지식은 근무경력에 따라 유의한 차이가 있었으며 표준주의지침 안전환경은 직위에 따라 유의한 차이가 있었다. 표준주의지침 지식 정도는 평균 21.98(25점 만점), 안전환경은 평균 5.68(7점 만점), 수행도는 평균 40.28(60점 만점)이었으며, 표준주의지침 안전환경과 표준주의지침 수행도(r=.21, p<0.01)는 유의한 양의 상관관계가 있었다. 표준주의지침 수행도에 미치는 영향요인은 표준주의지침 안전환경(𝛽=.22, p=.003)으로 나타났다. 따라서 공공의료기관에서 간호사의 감염관리를 위한 표준주의지침 수행도를 증진 시키기 위해서는 재정적 지원 및 지지적 안전환경을 제공하고 현 상황을 고려한 차별화된 감염관리 교육프로그램과 모니터링이 요구된다.

• Safety and Health at Work
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• 제7권2호
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• pp.124-129
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• 2016

Background: Work-related fatigue has a strong impact on performance and safety but so far, no agreed upon method exists to detect and quantify it. It has been suggested that work-related fatigue cannot be quantified with just one test alone, possibly because fatigue is not a uniform construct. The purpose of this study is therefore to measure work-related fatigue with multiple tests and then to determine the underlying factorial structure. Methods: Twenty-eight employees (mean: 36.11; standard deviation 13.17) participated in five common fatigue tests, namely, posturography, heart rate variability, distributed attention, simple reaction time, and subjective fatigue before and after work. To evaluate changes from morning to afternoon, t tests were conducted. For further data analysis, the differences between afternoon and morning scores for each outcome measure and participant (${\Delta}$ scores) were submitted to factor analysis with varimax rotation and each factor with the highest-loading outcome measure was selected. The ${\Delta}$ scores from tests with single and multiple outcome measures were submitted for a further factor analysis with varimax rotation. Results: The statistical analysis of the multiple tests determine a factorial structure with three factors: The first factor is best represented by center of pressure (COP) path length, COP confidence area, and simple reaction time. The second factor is associated with root mean square of successive difference and useful field of view (UFOV). The third factor is represented by the single ${\Delta}$ score of subjective fatigue. Conclusion: Work-related fatigue is a multidimensional phenomenon that should be assessed by multiple tests. Based on data structure and practicability, we recommend carrying out further studies to assess work-related fatigue with manual reaction time and UFOV Subtest 2.

• 한국안전학회지
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• 제23권4호
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• pp.79-84
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• 2008

Auto injector grouting method as low pressure injected by using epoxy and Boyle's law is very excellent method in economical efficiency and construction work because injected process can be dealt with collectively. For estimation of filling capacity purpose of this study compared the Auto injector method with the piston injector method. In this study, the tests allow for width of crack, injected angle of epoxy resin and injected method were performed using concrete block specimen making artificial crack. The results of test, tilling et1iciency of epoxy by Auto Injector grouting method verify to better than the piston injector method and uniaxial strength increased about 11% than standard specimen.

• Corrosion Science and Technology
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• 제13권3호
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• pp.112-119
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• 2014

In this work, it is aimed to develop the fabrication method of axial stress corrosion cracking (SCC) defects having various sizes, on the outer diameter surface of the steam generator (SG) tubings. To control the length of the artificial SCC defect, the specific area of the SG tubing samples was exposed to an acidic solution after a sensitization heat treatment. During the exposure to an acidic solution, a direct current potential drop (DCPD) method was adopted to monitor the crack depth. The size of the SCC defect was first evaluated by an eddy current test (ECT), and then confirmed by a destructive examination. From the comparison, it was found that the actual crack length was well controlled to be similar to the length of the surface exposed to an acidic solution (5, 10, 20 or 30 mm in this work) with small standard deviation. From in-situ monitoring of the crack depth using the DCPD method, it was possible to distinguish a non-through wall crack from a through wall crack, even though the depth of the non-through wall crack was not able to be precisely controlled. The fabrication method established in this work was useful to simulate the SCC defect having similar size and ECT signals as compared to the field cracks in the SG tubings of the operating Korean PWRs.

• 한국재난정보학회 논문집
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• 제19권4호
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• pp.984-992
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• 2023

연구목적: 본 연구의 핵심 문제는 국내 발파 작업에 대한 구체적인 소음규제 기준이 없다는 점이다. 현재 국내의 발파작업 소음규제 기준이 별도로 제정되지 않고 일일생활소음 기준인 70데시벨에 10데시벨 보정하여 80데시벨의 소음규제 기준을 갖고 있다. 대조적으로 많은 외국에서는 발파작업에 특별히 맞춰진 별도의 소음규제 기준을 갖고 있다. 이에 국내외 발파작업 소음규제 기준을 비교하여 국제적인 합리적 발파소음 기준을 제시하고자 한다. 연구방법: 국내외 소음규제 기준을 비교 분석한 것으로 유추할 수 있다. 현행 국내의 발파작업시 소음규제 기준과 미국, 영국, 호주, 일본 및 중국 등의 발파작업시 소음규제 기준에 관한 데이터 수집 및 분석을 한다. 연구결과: 국내 건설현장의 발파작업시 소음규제 값은 별도로 제정되지 않아 발파소음의 특정, 특성에 적절하게 맞춰져 있지 않은 것으로 나타났다. 해외의 경우 발파작업시 소음규제 값에 대해 생활소음 규정 등을 일률적으로 적용하는 것은 보다 안전하고 효율적이며 친환경적인 발파공법을 적용할 수 있도록 현실적인 소음규제 값을 제정 하였다. 결론: 국내외 비교 연구한 내용과 같이 합리적인 발파작업시 소음규제 값을 제정하여 발파안전 기준을 잘 준수하여 효율적이며 경제적이고 친환경적인 발파공법의 도입을 방해하지 않고 널리 채택되기를 바란다.

• Safety and Health at Work
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• 제10권2호
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• pp.196-204
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• 2019

Background: Liquid chromatography-tandem mass spectrometry (LC-MSMS) for simultaneous analysis of multiple microbial secondary metabolites (MSMs) is potentially subject to interference by matrix components. Methods: We examined potential matrix effects (MEs) in analyses of 31 MSMs using ultraperformance LC-MSMS. Twenty-one dust aliquots from three buildings (seven aliquots/building) were spiked with seven concentrations of each of the MSMs ($6.2pg/{\mu}l-900pg/{\mu}l$) and then extracted. Another set of 21 aliquots were first extracted and then, the extract was spiked with the same concentrations. We added deepoxy-deoxynivalenol (DOM) to all aliquots as a universal internal standard. Ten microliters of the extract was injected into the ultraperformance LC-MSMS. ME was calculated by subtracting the percentage of the response of analyte in spiked extract to that in neat standard from 100. Spiked extract results were used to create a matrix-matched calibration (MMC) curve for estimating MSM concentration in dust spiked before extraction. Results: Analysis of variance was used to examine effects of compound (MSM), building and concentration on response. MEs (range: 63.4%-99.97%) significantly differed by MSM (p < 0.01) and building (p < 0.05). Mean percent recoveries adjusted with DOM and the MMC method were 246.3% (SD = 226.0) and 86.3% (SD = 70.7), respectively. Conclusion: We found that dust MEs resulted in substantial underestimation in quantifying MSMs and that DOM was not an optimal universal internal standard for the adjustment but that the MMC method resulted in more accurate and precise recovery compared with DOM. More research on adjustment methods for dust MEs in the simultaneous analyses of multiple MSMs using LC-MSMS is warranted.