• 한국입자에어로졸학회지
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• 제12권3호
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• pp.51-56
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• 2016

Due to recent development in nanotechnology and increasing usage and production of nanomaterials, numerous studies related to environment, sanitation and safety handling of nanoparticle are being conducted. Since nanoparticles can be easily absorbed into human bodies through breathing process, based on their toxic substances and their large specific surface, these particles can cause serious health damage. Therefore, to reduce nanoparticle emissions, nanofiltration technology is becoming a serious issue. Filtration is a separation process during which a fluid passes through a barrier by removing the particles from the stream. Barrier filters can be made of various materials and shapes. One of the most common type of barrier filter is the fibrous filter. Fibrous filters are divided in two types: nonwoven and woven fabrics. Polypropylene is a thermoplastic material, used as a base material for melt blown nonwoven fabric. In this study, we examined filtration property of KCl nanoparticles with a mean particle diameter of 75 nm using multilayer meltblown filter samples. These experiments verify that the penetration of nanoparticle in the filter correlate with pressure drop; the meltblown layer MB1 has the greatest effect on dust collection efficiency of the filter. Among all tested samples, dust collection efficiency of 2-layer filter was best. However, when considering the overall pressure drop and dust collection efficiency, the 4-layer filter has the highest quality factor for particles smaller than 70 nm.

• 대한토목학회논문집
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• 제34권3호
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• pp.785-794
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• 2014

유역에서의 수문반응은 기후요소뿐만 아니라 토지이용, 토양, 식생 등의 여러 가지 요소에 의한 복합적 상호작용에 의해 결정된다. 따라서 유역의 수문반응을 효과적으로 파악하기 위해서는 기후요소와 다른 외부요소에 대한 특성이해가 필요하다. 본 연구에서는 수문지수(건조지수, Horton 지수)를 적용하여 유역 수문반응에 영향을 미치는 기후 및 유역 특성의 상대적 영향력을 확인하고자 하였다. 우리나라 자연 유역에서는 건조지수보다는 Horton 지수를 이용하여 유역의 수문반응을 평가하는 것이 효과적이었다. 또한 기후상태에 따라 기후요소와 유역특성이 미치는 상대적인 영향력이 달라지는데, 건조한 기후상태에서는 기후요소가 지배적으로 수문반응에 영향을 미쳤으나 기후가 습윤한 상태로 갈수록 유역특성의 역할이 상대적으로 증가하고 있음을 확인하였다.

• 한국지리정보학회지
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• 제13권1호
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• pp.1-15
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• 2010

본 연구는 GIS 기반의 SWAT (Soil and Water Assessment Tools) 모형을 이용하여 탁수발생 잠재가능성 평가지표를 개발하고 수계별 탁수 관리방안 대책을 지원하기 위해 기후변화에 따른 안동호와 임하호 유역의 유출량과 부유사량의 변화특성을 분석하였다. 장래 기후변화자료는 IPCC (Intergovernmental Panel on Climate Change)에서 제공하는 A1B 기후변화시나리오의 MIROC3.2 hires 모델의 결과값을 이용하여 생성하였다. 과거의 기후자료(1977~2006)를 기반으로 20C3M (20th Century Climate Coupled Model) 모의값을 이용하여 강수와 온도를 보정한 뒤 CF (Change Factor) 기법으로 downscaling 하였다. 미래 기후변화 시나리오는 세 기간(2020s, 2050s, 2080s)으로 나누어 분석하였고, SWAT 모형과 연계하여 기후변화에 따른 유출량 및 부유사량의 변화를 산출하였다. 2020s, 2050s, 2080s 기간동안의 안동호와 임하호 유역의 유출량과 부유사량은 기준년도(2006)에 비해 증가하였고, 계절적인 분석에서도 봄, 가을, 겨울철 안동호와 임하호 유역의 유출량과 부유사량이 기준년도에 비해 증가하는 것으로 모의되었다. 단, 여름철 유량과 부유사량은 2020s에만 증가하고 2080s에는 감소하는 것으로 분석되었다.

• Safety and Health at Work
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• 제8권3호
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• pp.290-295
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• 2017

Background: Safety climate and occupational stress are related with occupational accident. The present study tried to identify the differences in safety climate and occupational stress according to occupational accidents experience and employment type (e.g., direct workers and subcontract workers). Methods: In this study, we conducted a survey using safety climate scale and Korean Occupational Stress Scale and classified the participants into four groups: direct workers working for accident-free departments, direct workers working for accident departments, subcontract workers working for accident-free departments, and subcontract workers working for accident departments for 2 years within the same workplace in the shipbuilding industry. Results: The direct workers and subcontract workers showed diverse results in subscales of safety climate and occupational stress. This result is supported by existing studies; however, further study is necessary for more supporting evidence and elaborative methodological approach. Conclusion: The necessity of management for safety climate and psychosocial factor such as occupational stress for both direct workers and subcontract workers as a whole is suggested by this study.

• 간호행정학회지
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• 제22권5호
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• pp.471-479
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• 2016

Purpose: This study was conducted to evaluate the level of safety climate, fatigue, and safety performance and to identify the impact of safety climate and fatigue on the safety performance of operating room nurses. Methods: The study design was a descriptive survey. Participants were 174 operating room nurses from two general hospitals and two university hospitals in S and D cities. Three structurally designed questionnaires were used to evaluate their safety climate, fatigue, and safety performance. Collected data were analyzed using descriptive analysis, t-tests, ANOVAs, Pearson correlation coefficient, and stepwise multiple regression. Results: Safety performance of operating room nurses had a mean of 3.26 on a 5-point scale. 'Current department career'(${\beta}=.17$, p=.006) and 'safety climate (work-unit contribution) (${\beta}=.63$, p<.001) accounted for 39% of the variance in operating room nurses' safety performance. Conclusion: Findings indicate that work-unit contribution towards safety climate is an important factor in increasing operating room nurses' safety performance. Therefore, it is essential to find motivational properties consistent with the characteristics of the operating room environment.

• 한국기후변화학회지
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• 제7권3호
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• pp.357-371
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• 2016

Buildings in the city acts as a cause of distorted wind direction, wind speed, causing the stagnation of the air flow. In the recent trend of climate change can not but consider the temperature rise of the urbanization. This study was aimed to analyze the thermal comfort of planetary boundary layer in different artificial constructions areas which has a direct impact on urban climate, and estimating the warming phenomena. Envi-met model was used to consider the urban structure associated with urban growth in order to precisely determine the impact of the building on the city weather condition. The analyzed values of thermal comfort index were temperature, wind speed, horizontal and vertical turbulent diffusivity. In particular, analysis of the PPD(Predicted Percentage of Dissatisfied) represents the human thermal comfort. In this study, by adjusting the arrangement and proportion of the top floor building in the urban it was found that the inflow of the fresh air and cooling can be derived low PPD. Vertical heat flux amount of the city caused by climate change was a factor to form a high potential temperature in the city and the accumulation of cold air does not appear near the surface. Based on this, to make the city effectively respond to climate change may require a long-term restructuring of urban spatial structure and density management.

• 영어영문학
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• 제57권1호
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• pp.3-25
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• 2011

As extremes of climate such as heavy storms, rainfalls, and droughts tend to be routine in recent years, global climate change becomes a serious concern not only for natural scientists but also for scholars of the human sciences. Efforts to tackle the anthropogenic climate change certainly require not only scientific knowledge about it but also a new sociocultural paradigm for valorizing and respecting nature in its own right. The huge casualties and mass destruction caused by recent climate disasters also remind us that nature has been an important factor to bring about changes in human history-a fact largely ignored in traditional history. This again validates the ecocritical request to prioritize place, physical setting, or the relationship characters hold with the natural world in understanding literary works. In this context this paper aims to demonstrate the importance of the meteorological vision in creating as well as understanding literary and cultural texts by examining such works as Shelley's "The Cloud," Byron's "Darkness," Keats's "To Autumn," all produced during the period of dramatic climate change including "the year without summer." It also briefly discusses Roland Emmerich's 2004 movie The Day after Tomorrow as a way of understanding recent cultural responses to the crisis of global warming.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 유기절연재료 방전 플라즈마연구회
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• pp.49-52
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• 2003

The performance of insulators under contaminated conditions is the underlying and the most factor that determines insulation design for outdoor applications, Among the contamination factors, The sea salt is the most dangerous factor, and the salt factor have closed relation with climatic conditions, such as wind, temperature, humidity and so on, Effect of these factors to insulation system is different of each other, and need to show the correlation by multiple regression analysis techniques. In this paper, predicted and analyzed equivalent salt deposit density (ESDD) by change climatic condition through multiple regression analysis.

• 통상정보연구
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• 제6권3호
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• pp.123-136
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• 2004

In recent years, although far behind, the "e-Trade (B to G)" is propelled vigorously in Japan. But the diffusion of the "e-Trade" among companies (B to B) represented by bolero.net does not meet expectation. This paper carried out the questionnaire survey to the enterprises, which adopt bolero.net and examined why the diffusion is stagnated to the measures for its future spread. As a result, the top 3 adoption factors are: (1) Transaction climate, (2) Top management support, and (3) Operational improvement. In other words, it depends that top management has the will, which adopts e-trade positively among the reliable business partners and the operational performances can improve efficiently by carrying e-trade. We would like to clarify what will be crucial to spur the diffusion in the future. Based on the findings from the result, the concrete key points to promote the spread are to be indicated as follows: (1) Improve the scores of "Cost" and "Competitive pressure" (2) Improve the institutional factor.

• 한국기후변화학회지
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• 제10권3호
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• pp.237-242
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• 2019

Ammonia is main precursor gas of secondary particulate matter and contributes almost 78% of total ammonia emission from the agricultural sector in Korea. The current method of estimating ammonia emission from fertilizer application, which contributes 7% of the total emission, has high uncertainty and needs to be improved to better predict PM2.5 concentration. In this study, we suggest an improvement method for ammonia emission quantification from fertilizer application. The first improvement was in the emission factor of NPK fertilizer by conducting a field study to verify the currently used factor. The improved NPK emission factor of 52.2 kg NH ton-1N was confirmed by comparing with the value from the EEA (European Environment Agency) and adjusting the value for the Korean climate and soil conditions. We also improved the amount of fertilizer usage by including the sales amount to the fertilizer supply amount of the Korean Farmers Association, increasing total fertilizer usage by 39.8%. As the statistical data on fertilizer supply and sales are compiled yearly, we estimated monthly emission of ammonia by considering cultivated areas and timing of fertilization for each crop. In summary, we suggest a novel and practical method to improve estimation methodology of ammonia emission from the field of fertilizer application: 1) emission factor of NPK fertilizer was reconfirmed; 2) total amount of fertilizer use was revised considering fertilizer sales; and 3) monthly emission of ammonia was realized by considering different crop practices. A bottom-up approach to compile activity data is needed to increase the estimation accuracy of monthly emission of ammonia, which is very helpful for predicting PM2.5 concentration.