• 환경영향평가
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• 제31권6호
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• pp.378-387
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• 2022

대기오염이 국제적으로 해결해야 하는 공통과제가 되었으며 국내에서는 지나친 대기오염을 예방하기 위해 개발 사업 이전에 환경영향평가를 통해 대기질 영향을 예측하고 사업 진행 이후에는 사후환경영향 조사를 통해 대기질을 관리하고 있다. 해당 데이터를 확인하고 정합성을 분석하여 조사과정과 영향 예측기준 등에 대한 개선 방향을 제시하고자 하였다. 운영 시 측정까지 완료된 2017년에서 2019년 사이의 환경영향평가 대상 사업 중 선형사업의 공사 시 농도를 대상으로 연구를 진행하였다. 분석 결과는 크게 데이터를 비교하여 환경영향평가 예측치의 대기오염 기준 하향, 5년 이상 장기사업은 오염물질 배출 기준 등을 강화, 현황조사 시 농도가 높게 실측되는 1분기와 2분기를 포함하는 개선방안과 정합성 분석을 통해 대기질의 과대 추정을 방지하기 위해 투입되는 건설장비의 종류나 사업 조건들을 설정하여 상황에 맞는 적합한 최대 배출농도를 예측하는 방향을 제시하였다. 본 연구는 데이터를 활용하여 환경영향평가 과정의 현황을 파악하고 그로부터 대기질 유지를 위한 규정이나 조사 방법 등 개선이 필요한 요소들을 파악하여 개선방안을 제안했다는 데 의의가 있다.

• 한국환경농학회지
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• 제42권2호
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• pp.112-120
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• 2023

Methane (CH₄) and nitrous oxide (N₂O) are significant contributors to greenhouse gas (GHG) emissions from rice fields. Mid-summer drainage is a commonly practiced water management technique that reduces CH₄ emissions from rice fields. Slow-release fertilizers gradually release nutrients over an extended period and have been shown to reduce N₂O emissions. However, the combined effect of slow-release fertilizer and water management on GHG emissions remains unclear. This study compared GHG emissions from a rice paddy subjected to mid-summer drainage for 10 days (control) with that of a rice paddy subjected to prolonged mid-summer drainage for 20 days combined with slow-release fertilizer (W+S). Gas sampling was conducted weekly using a closed chamber method. During the rice cultivation period, cumulative CH₄ and N₂O emissions were reduced by 12.3% and 16.2%, respectively, in the W+S treatment compared to the control. Moreover, the W+S treatment exhibited a 1.9% increase in grain yield compared to the control. Under experimental conditions, slow-release fertilizers, in combination with prolonged mid-summer drainage, proved to be the optimal approach for achieving high crop yield while reducing GHG emissions. This represents an effective strategy to mitigate GHG emissions from rice paddy fields.

• 정신신체의학
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• 제3권2호
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• pp.159-165
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• 1995

본 연구의 목적은 시험과 같은 심리적 스트레스와 혈청 cortisol 및 prolactin과의 관계를 알아보고, 주관적인 스트레스지각 및 정신병리가 혈청 cortisol 및 prolactin치 간의 상관성을 알아보는데 있다. 본 연구에는 의과대학 남학생 20명이 참여하였다. 이들을 대상으로 시험기간과 수업기간 중에 각각 global assessment of recent stress(GARS)척도와 SCL-90R척도를 사용하여 스트레스지각 및 정신병리를 평가하였다. 혈청 cortisol 및 prolactin치는 방사성 면역측정법에 의해 측정되었다. 혈청 cortisol치는 수업기간보다 시험기간 중에 유의하게 더 높았으나 혈청 prolactin치는 두 군 간에 유의한 차이를 보이지 않았다. 한편 시험기간 및 수업기간 중 스트레스지각점수는 혈청 cortisol치 및 prolactin치와 각각 유의한 상관성을 보이지 않았다. 그러나 정신병리에 있어서는 시험기간 중 대인예민척도점수가 혈청 cortisol치와 유의한 음 상관성을 보였다. 이상의 결과는 시험과 같은 심리적 스트레스가 prolactin보다 cortisol과 더 밀접하게 관련될 가능성이 높음을 시사한다. 그리고 대인예민과 같은 특정 정신병리는 낮은 혈청 cortisol치와 관련될 수 있음을 시사한다.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2000년도 춘계 학술발표회 논문집 Proceedings of EESK Conference-Spring
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• pp.233-240
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• 2000

Nuclear power plant structures may be exposed to aggressive environmental effects than may cause their strength and stiffness to decrease over their service lives, Although the physics of these damage mechanisms are reasonably well understood and quantitative evaluation of their effects on time-dependent structural behavior is possible in some instances such evaluations are generally very difficult and remain novel. The assessment of existing RC containment in nuclear power plants for continued service must provide quantitative evidence that they are able to withstand future extreme loads during a service period with an acceptable level of reliability. Rational methodologies to perform the reliability assessment can be developed from mechanistic models of structural deterioration using time-dependent structural reliability analysis to take earthquake loading uncertainties into account. The final goal of this study is to develop the reliability analysis of RC containment structures. The cause of the degrading is first clarified and the reliability assessment has been conducted. By introducing stochastic analysis based on random vibration theory the reliability analysis which can determine the failure probabilities has been established.

• 한국군사과학기술학회지
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• 제21권5호
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• pp.714-721
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• 2018

This study proposes a risk evaluation method based on RAM and AHP data in order to prevent subjectivity of risk assessment. The risk assessment consist of Risk Likelihood(RL) and Risk Consequence(RC) in five levels. However, risk analysis of warships is hard to make a judgment because of small quantity production(Ship), long building period, equipment changes, complexity, various kinds of equipments, etc. The proposed RAM data and AHP analysis method are used to quantify each level quantitatively. RAM(MTBF) date is used to classify the RL, and AHP analysis is used to classify the RC. These scientific and data-based method will increase objectivity as well as efficiency of risk evaluation.

• 한국학교보건학회지
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• 제1권1호
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• pp.148-159
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• 1988

For the evaluation of physical assessment by school nurses, this study was designed in two steps physical assessment. The first step is the primary health screening by school health nurses. The second step is the Physicians' physical examination of ill health students selected by school nurses. This study was conducted on a total of 3,525 students of three primary schools located in urban, township, and rural area during the period from May to June, 1987, all data were collected through direct observation & survey method. The main findings are as follows 1. The number of ill health students selected by two step method was more than that of one step method by the physician. 2. The types of ill health students selected by two step method had more diversity than that of one step method by the physician. 3. Budgets and time consumption for two step method were more reductive than that of one step method by the physician.

• Structural Engineering and Mechanics
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• 제4권4호
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• pp.347-364
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• 1996

Presently welded components are designed using S/N curves which predict only the fatigue life of the component. In order to ascertain the condition of the weld at any intermediate period of its life inspection is carried out. If cracks are detected in a weld fracture mechanics is used to find their remaining life. A procedure for assessment is developed here that can be used to verify the condition of a weld before inspection is carried out to detect cracks. This simple method has been developed using linear fracture envelopes by combining S/N curves with linear elastic fracture mechanics.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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• pp.229-232
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• 1999

Nuclear power plant structures may be exposed to aggressive environmental effects that may cause their damage mechanisms are reasonably well understood and quantitative evaluation of their effects on time-dependent structural behavior is possible in some instances, such evaluations are generally very difficult and remain novel. The assessment of existing steel containment in nuclear power plants for continued service must provide quantitative evidence that they are able to withstand future extreme loads during a service period with an acceptable level of reliability. Rational methodologies to perform the reliability assessment can be developed from mechanistic models of structural deterioration, using time-dependent structural reliability analysis to take loading and strength uncertainties into account. The final goal of this study is to develop the analysis method for the analysis for the reliability of containment structures. The cause and mechanism of corrosion is first clarified and the reliability assessment method has been established. By introducing the equivalent normal distribution, the procedure of reliability analysis which can determine the failure probabilities has been established.

• 품질경영학회지
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• 제40권3호
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• pp.259-269
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• 2012

Purpose: The purpose of this study was to find out that the statistical method of stockpile reliability of ammunition by items can be applied to the reliability assessment of stockpile ammunition. Methods: We reviewed the statistical method of stockpile reliability of ammunition by items and verified the possibility of its application by case study. Results: We found that the statistical method of stockpile reliability of ammunition by items is very useful and effective to present the reliability of ammunition based on each item and to predict the change of the reliability in the future. The reliability of proximity fuse was about 94.5% and was influenced by manufacture's year and the difference between lot and lot more than storage period. Conclusion: The statistical method of stockpile reliability of ammunition by items can be applied to the reliability assessment of various stockpile ammunitions such as ammunition for mortar and canon.

• 환경영향평가
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• 제15권1호
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• pp.45-52
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• 2006

The purpose of this study is to assess spatiotemporal variation of coastal water quality according to time and location changes. For this we developed numerical marine trophic index base on four water quality components (chlorophyll, suspended solids, dissolved inorganic nitrogen and phosphorus) and applied this index to the water quality data measured in the korean coastal zone for the 7-years period from 1997 to 2003. Water quality data are obtained only at selected sites even though they are potentially available at any location. Therefore, in order to estimate spatial variation of coastal water quality, it is necessary to estimate the unknown values at unsampled locations based on observation data. In this study, we used IDW (Inverse Distance Weighted) method to predict water quality components at unmeasured locations and applied marine trophic index to predicted values obtained by IDW interpolation. The results of this study indicate that marine trophic index and spatial interpolation are useful for understanding spatiotemporal characteristics of coastal water quality.