• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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• pp.453-456
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• 2004

This paper surveys the latest findings on vegetable-oil-based dielectric coolants in power systems. In recent years, environmental concerns have been increased on the use of poorly biodegradable mineral oils in distribution and power transformers in regions where spills from leaks and equipment failure could contaminate the surroundings. In addition, there are demands to improve equipment efficiencies in power systems. In this reason, researches were started in the mid 1990s to develop a fully biodegradable dielectric coolants. Vegetable oil was considered the most likely candidate for a fully biodegradable dielectric coolants. Vegetable-oil-based dielectric coolants provide the advantages of high level of biodegradability, renewable natural resource, non-toxic properties, enhanced fire safety, more effective cooling and good dielectric strength for many electrical equipment.

• Journal of Microbiology
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• 제43권spc1호
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• pp.118-131
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• 2005

Vibrio vulnificus is an opportunistic pathogen of humans that has the capability of causing rare, yet devastating disease. The bacteria are naturally present in estuarine environments and frequently contaminate seafoods. Within days of consuming uncooked, contaminated seafood, predisposed individuals can succumb to sepsis. Additionally, in otherwise healthy people, V. vulnificus causes wound infection that can require amputation or lead to sepsis. These diseases share the characteristics that the bacteria multiply extremely rapidly in host tissues and cause extensive damage. Despite the analysis of virulence for over 20 years using a combination of animal and cell culture models, surprisingly little is known about the mechanisms by which V. vulnificus causes disease. This is in part because of differences observed using animal models that involve infection with bacteria versus injection of toxins. However, the increasing use of genetic analysis coupled with detailed animal models is revealing new insight into the pathogenesis of V. vulnificus disease.

• 산업경영시스템학회지
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• 제26권3호
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• pp.39-49
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• 2003

Statistical process cintrol is intended to assist operators of a stable system in monitoring whether a change has occurred in the process, and it uses several control charts as main tools. In design and use of control chart, it is rational that probability of false alarm is minimized in stable process and probability of detecting shifts is maximized in out-of-control. In this study, we establish bootstrap control limits for robust M-estimator chart by applying the bootstrap method, called resampling, which could not demand assumptions about pre-distribution when the process is skewed and/or the normality assumption is doubt. The results obtained in this study are summarized as follows : bootstrap M-estimator control chart is developed for applying bootstrap method to M-estimator chart, which is more robust to keep ARL when process contain contaminate quality characteristic.

• 천문학회보
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• 제46권1호
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• pp.54.1-54.1
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• 2021

Observing sub-mm continuum emission from cold dust can play an important role in measuring star formation rates of galaxies, especially in the case of AGN host ones, since AGNs contaminate FIR fluxes by dust heating. To measure star formation rates, we observed total 49 local AGN host galaxies(z<0.2) by SCUBA-2 camera at James Clerk Maxwell Telescope(JCMT) at 450㎛ and 850㎛. We performed several tests with the observed images to determine whether each source is detected, and adopted 3s as the flux upper limit in non-detection cases. Using these measurements and FIR archival data, we modeled spectral energy distributions of the galaxies to estimate star formation rates. The effect of AGN activity on host galaxy star formation will be discussed.

• 한국환경보건학회지
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• 제41권5호
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• pp.335-348
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• 2015

Objectives: We aimed to assess the risk of metabolic syndrome one year after the 2007 Hebei Spirit oil spill in Taean, Korea among people exposed to spilt oil during clean-up work. Methods: A total of 6,923 adults, including 3,019 males and 3,904 females, participated in the study. Health examinations and blood tests (total cholesterol, triglycerides, HDL, fasting blood sugar) were performed. A logistic regression model adjusting for age, gender, smoking history, drinking history, income, education, and marital status was used to estimate the risk of metabolic syndrome associated with the level of oil spill exposure. Results: The prevalence of metabolic syndrome was 24.9% among males and 18% among females. Compared with people living within 20 km of the coastline, the risk of metabolic syndrome among people living within 0.8 km of the coastline was significantly higher (male OR=1.696, 95% CI=1.320-2.178, female OR=1.992, 95% CI=1.549-2.561), including a significant dose-response relationship for distance from early contaminate coastline (p<0.001). The risk of metabolic syndrome was higher according to the increase of duration of cleaning work. The risk of metabolic syndrome among people who participated in the clean-up work for more than 116 days, compared with people who participated in the cleaning work for or less 14 days, was significantly higher (male OR=1.845, 95% CI=1.448-2.353, female OR=1.752, CI=1.378-2.228), with a significant dose-response relationship for days of clean-up work (p<0.001). Conclusion: This study showed that there is a significant association between exposure to the oil spill during the clean-up work, distance from early contaminate coastline and the risk of metabolic syndrome in a doseresponse manner.

• Fisheries and Aquatic Sciences
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• 제5권1호
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• pp.48-53
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• 2002

The HACCP (hazard analysis critical control point) concept becomes an important aspect of Good Manufacturing Practices (GMP) in safe food production. The HACCP plan was developed with food safety objective. The authors already carried out hazards analysis on Changran Jeotgal manufacturing process in a previous report. In this study we developed a HACCP plan on the manufacturing process of Changran Jeotgal. We could decide two CCPs those were salt concentration and eliminations of foreign materials before packaging. Foreign materials should be certainly checked out with laser detector just before packaging. Salt should be maintained more than $8\%$ to inhibit pathogenic bacteria in end product. On the Jeotgal process free water is removed after salting and Jeotgal is seasoned with several subsidiary materials such as com syrup. In result end products have $8\%$ salt with water activity 0.82. Most bacteria are inhibited but some can live in this condition. Materials on the working may be contaminate by pathogens, chemicals or physical hazards. It will be decreased by SSOP (standard sanitary operating program). The SSOP needed in Jeotgal plants is nearly same as other general food manufacturing plants but essential to fulfill HACCP program.

• 한국지하수토양환경학회지:지하수토양환경
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• 제17권6호
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• pp.1-8
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• 2012

This study is to suggest a few efficient ways of rainwater utilization, through monitoring and analyzing 143 rainwater storage systems and 110 artificial recharge systems, which are installed in the recommended facilities by law, among the rainwater harvesting systems in Jeju Island. In the case that catchment facilities are damaged, rainwater could be contaminated by leaves and debris so that the rates of rainwater usages come to be lower. It is possible that contaminated rainwater could contaminate artificial recharge wells or rainwater discharging out of the rainwater harvesting system could result in flood and damage for the downgradient area. For maintaining high quality of rainwater and increasing rainwater utilization rate, it is necessary to install screening facilities and purification plant functioning precipitation and filtration. Also, in order to efficiently preclude the overflowing rainwater exceeding storage capacity, it is recommended to associate rainwater storage tanks with artificial recharge well or infiltration trench facilities.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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• pp.63-67
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• 2002

The induced chemical and salt solution in water or admixture are originated to the corrosion process of the steeo rebar. These liquids penetrate into concrete as the accompanied by the chemical reaction and cause to attack the steel rebar in concrete. Concrete surfaces which it exposed to deicing, water and sea water is allowed to enter the chlorides in the structures. To prevent from the source of corrosion and deterioration Is subjected to put an end to corrode or reduce to contaminate on the steel rebar. As this reason the MCI 2022 products are applied to the surface of concrete and steel rebar. The concrete samples were made of to the kind of four, i.e. RF, MR, MS, and MM. Corrosion inhibitor is applied to coat on the surface of concrete after it had been cured for 28days. Specimen were immersed in a 3.5％ sodium chloride solution. Concrete specimen were tested to determine the changes of the resistance polarization, Rp, over a 22 weeks period. MCI 2022 is significantly shown the corrosion inhibition of steel rebar in 3.5% NaCl solution. In the each different concrete sample, MS and MM is seemed to be better than others. The results are proofed that MCI 2022 is promised to maintain the inhibition of corrosion with high resistance polarization of the steel rebar in concrete.

• Applied Biological Chemistry
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• 제47권1호
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• pp.1-16
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• 2004

이 논문에서는 식품 또는 식품원료 중의 aflatoxin에 관한 오염현황, 최신 분석법 그리고 저감화 시킬 수 있는 방안에 대해 조명하였다. Aflatoxin은 여러 곰팡이가 생성하는 2차 대사산물로서 곰팡이 독소 중 가장 독성이 강한 것으로 알려져 있다. 발암성을 포함한 독성 관계로 aflatoxin은 인간의 건강 측면 뿐 아니라 식품을 포함한 산업전반에 경제적으로 큰 영향을 끼치고 있다. 우리나라와 같은 식량 수입국에서는 식품의 안전성 확보를 위해 노출량 조사, 위해평가 및 관리가 체계적으로 이루어져야 하며 아울러 새로운 aflatoxin 분석 기술의 개발과 독성 저감화 기술의 개발이 병행되어야 한다고 판단된다.

• 대기
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• 제17권1호
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• pp.17-26
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• 2007

The station relocations, the replacement of instruments, and the change of a procedure for calculating derived climatic quantities from observations are well-known nonclimatic factors that seriously contaminate the worthwhile results in climate study. Prior to embarking on the climatological analysis, therefore, the quality and homogeneity of the utilized data sets should be properly evaluated with metadata. According to the metadata of the Korea Meteorological Administration (KMA), there have been plenty of changes in the procedure computing the daily mean values of temperature, humidity, etc, since 1904. For routine climatological work, it is customary to compute approximate daily mean values for individual days from values observed at fixed hours. In the KMA, fixed hours were totally 5 times changed: at four-hourly, four-hourly interval with additional 12 hour, eight-hourly, six-hourly, three-hourly intervals. In this paper, the homogeneity in the daily mean temperature dataset of the KMA was assessed with the consistency and efficiency of point estimators. We used the daily mean calculated from the 24 hourly readings as a potential true value. Approximate daily means computed from temperatures observed at different fixed hours have statistically different properties. So this inhomogeneity in KMA climate data should be kept in mind if you want to analysis secular aspects of Korea climate using this data set.