• 펄프종이기술
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• 제42권3호
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• pp.7-13
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• 2010

KOptimization and control of wet-end process provide a key solution to improve paper quality and production efficiency at the same time. Wet-end of paper machine is to determine three important influencing factors of papermaking i.e., retention, drainage and formation. Good formation of paper could be made at the cost of deteriorated retention or drainage. In the same manner increase of retention aid could cause the bad formation of paper. It is very important to find a proper retention chemical which may satisfy one of three factors without the sacrifice of other two. Laboratory scale analyzing or screening chemical additives of wet-end was reported in this study based on RDA sheet molding. Different from the conventional test method, simultaneous consideration of three important wet-end properties could be made by RDA and consequently more reliable prediction of actual paper machine wet-end could be expected.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.644-644
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• 2013

Graphene is a two-dimensional sp2 layer material. Despite the short history in the empirical synthesis of the graphene layers, the academic/industrial unique features have brought highly significant interest in research and development related to graphene-related materials. In particular, the electrical and optical performances have been targeted towards pre-existing microelectronicand emerging nanoelectronic applications. The graphene synthesis relies on a variety of processing factors, such as temperature, pressure, and gas ratios involving H2, CH4, and Ar, in addition to the inherent selection of copper substrates. The current work places its emphasis on the role of experimental factors in growing graphene thin films. The thermally-grown graphene layers are characterized using physical/chemical analyses, i.e., four point resistance measurements, Raman spectroscopy, and UV-Visible spectrophotometry. Ultimately, an optimization strategy is proposed in growing high-quality graphene layers well-controlled through empirical factors.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2000년도 추계 학술발표회
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• pp.20.1-20
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• 2000

• Korean Chemical Engineering Research
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• 제56권4호
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• pp.435-440
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• 2018

Nyamplung (Calophyllum inophyllum Linn) is one of the most widely grown plants in Indonesia. In addition, nyamplung oil has a future competitive advantage in that it can be processed into biodiesel. However, conventional methods for transesterification of nyamplung oil have been less effective. Therefore, in this study biodiesel was produced using microwaves as one of the alternative methods that can improve the shortcomings of conventional methods. In addition, optimization of parameters such as microwave power, catalyst concentration and transesterification time was done using Box-Behnken design. The combination of microwave with CaO catalyst and treated with Box-Behnken design are considered as a new and modern method for production of biodiesel from nyamplung oil and optimizing the factors that affected the transesterification process. The results showed that factors such as microwave power of 449.29 W, concentration of catalyst of 4.86% and transesterification time of 10.07 min can produce optimal yield of biodiesel of 92.73% with reliability of 93.22%.

• 벤처창업연구
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• 제13권6호
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• pp.191-198
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• 2018

기술이전은 기술공급사와 기술도입사간의 위험과 이익을 공유함에 따라 다양한 동기를 가지고 기술이전을 결정하게 된다. 기술공급사는 기술도입사가 제공하는 경제적 요인, 위험요인, 정부의 정책 및 제도와 해당 기술이전기업들의 경영전략 등 여러 결정요인을 복합적으로 고려하여 기술이전 결정을 하게 된다. 본 연구에서는 화학산업에서 기술이전에 영향을 미치는 요인을 파악하고 기술이전 의도에 미치는 영향력을 분석하였다. 본 연구결과 기술이전 영향요인은 경제적 혜택 요인, 기술적 요인, 위험요인, 사회문화적 요인으로 나타났다. 기술도입사와 기술공급사의 기술이전 영향요인의 유의미한 차이는 경제적 혜택 요인은 기술공급사보다 기술도입사가 중요하게 고려하는 것으로 나타났으며, 기술적 요인은 기술공급사가 기술도입사보다 중요하게 고려하는 것으로 나타났다. 기술이전 의지는 기술도입사가 기술공급사보다 높게 나타났다.

• 대한지하수환경학회지
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• 제5권4호
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• pp.215-222
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• 1998

지하수 세균 군집에 미치는 환경요인의 영향을 분석하기 위하여, 서울 시내에서 음용수로 사용하는 2개 정점과 음용수외 생활용수로 사용하고 있는 8개 정점을 대상으로 조사하였다. 물리.화학적 환경요인과 중금속의 농도, 및 세균 군집의 분포 등 40개 변수를 분석한 결과, 음용수로 사용하는 정점을 제외한 나머지 정점에서 질산성 질소와 암모니아가 용수목적별 수질기준의 기준치 이상으로 측정되었다. 총세균은 5.1~41.4$\times$$10^{5}$cells/ml 범주로, 종속영양세균과 기능성 세균군집은 0.01~29.6$\times$$10^4$cfu/ml의 범주로 조사되었다. 세포외 효소의 활성도는 0.005~11.3$\mu$M/l/hr 의 범주로 나타났고, lipase, phophatase, $\beta$-glucosidase, cellulase, chitinase, amylase 순으로 활성도가 나타났다. 정점별로 조사된 세균 군집에 미치는 환경요인의 상호관계는 대응분석(correspondence analysis)과 다차원 척도법 분석(multidimensional scaling; MDS)으로 하였으며, 그 결과 4개의 집단으로 구분되었으며, 세균 군집에 미치는 주요한 환경요인은 정점별 잠재오염원과 일치하는 양상을 보였다.다.

• 대한안전경영과학회지
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• 제16권3호
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• pp.101-110
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• 2014

This study tried to identify the effects of ergonomic risk factors for absence from work of fire fighters in Korea. A self-administered questionnaire was prepared for this study. The questionnaire consisted of several parts such as 'general information', 'work-related factors', 'physical & chemical risk factors', 'ergonomic risk factors', and 'absence information'. A total of 7,098 fire fighters participated in this study. The data obtained from the survey was mainly analyzed by logistic regression. A total of 856 out of 7,098 fire fighters experienced absence from work. The risk factors such as gender, age, marital status, education level, total work year, work area. position, job rotation, noise, dust, organic solvent, skin contact with chemical substance, toxic waste, regional vibration, manual material handling, continuous standing posture, awkward working posture were associated with absence from work. Specifically, awkward working posture and manual material handling from ergonomic risk factors were major risk factors for absence from work.

• 한국환경보건학회지
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• 제30권5호
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• pp.487-492
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• 2004

Building materials are composed of very complex chemical compounds, and these indoor building materials discharge very much Volatile Organic Compounds(VOCs). We performed the environmental chamber test to investigate the Total VOCs(TVOCs) emission characteristics and emission factors about chemical and natural coating materials. As the result, we concluded that TVOCs emission are high at initial time and decreased in course of time. Natural paint was low emission level for TVOCs than chemical paint by small chamber test. The TVOCs emission factor-time profile showed a good fit with the results from the measured and predicted value.

• 한국정밀공학회지
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• 제17권3호
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• pp.184-191
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• 2000

Properties of pad are investigated to find the relationship between the chemical mechanical polishing(CMP) results, such as material removal rate and within wafer non-uniformity(WIWNU), and its properties. Polishing pressure is considered as important factors to affect the results, so behavior of ordinary polymer is studied to define the polishing result affecting properties of pad. Experimental setup is devised to identify the behavior of pad and several different pads are used in chemical mechanical polishing experiments to verify the correlations between pad properties and polishing results. The results indicate that the viscoelastic properties of pad had relationships with the polishing results, and shows correlation between suggested properties of pad and polishing result.

• Current Photovoltaic Research
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• 제4권2호
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• pp.80-86
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• 2016

Since the last five years it has become a lot of solar power plants installed. However, by installing the large-scale solar power station it is not easy to predict the actual generation years. Because there are a variety of factors, such as changes daily solar radiation, temperature and humidity. If the power output can be measured accurately it predicts profits also we can measure efficiency for solar power plants precisely. Therefore, Prediction of power generation is forecast to be a useful research field. In this study, out discovering the factors that can improve the accuracy of the prediction of the photovoltaic power generation presents the means to apply them to the power generation amount prediction.