• KSBB Journal
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• 제11권3호
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• pp.353-359
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• 1996

Thiobacillus ferrooxidans를 이용한 보다 효율적이고 현장에 직접 응용할 수 있는 우라늄 침출공정을 개발하기 위하여 배양조건의 확립과 교반 반응기 및 이중기포탑 반융기에서의 우라늄 침출에 대한 연구 를 수행하였다. 배지의 초기 $Fe^{2+}$ 농도는 원광석 40g/L에 대하여 16.2g/L를 이용하는 것이 적합하였으며, 원광석의 업자는 작을수록 우라늄 침출율이 증가하였다. 또한 원광석의 첨가량이 많을수록 우라늄의 침출속도는 증가하였으나 침출율은 약간씩 감소하였다. 교반 반 응기 빛 이중기포탑 반응기에서의 우라늄 침출에 대한 실험을 최적조건에서 수행한 결과 교반 반응기에 서는 진탕배양기에서와 통일하게 12일 배양시 39.3%의 침출율로 5.5mgjL의 우라늄을 얻었다. 반면 이중기포탑 반응기에서는 교반 반응기에 비하여 세 균수가 2.4배 증가하였으며, 우라늄의 침출율과 침출된 우라늄 농도도 각각 91.4%와 12.8mgjL으로 교반 반응기 보다 2.3배 증가하였다. 이러한 결과는 이중기포탑 반응기에서는 충분한 양의 산소와 이산 화탄소의 공급과 원광석의 혼합이 잘됨으로써 세균 의 활성이 크게 증가하여 우라늄 침출이 향상된 것으로 추정된다.

• 국제학술발표논문집
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• The 4th International Conference on Construction Engineering and Project Management Organized by the University of New South Wales
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• pp.413-419
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• 2011

Corporate governance is a system articulating the division of responsibilities among different company members, and defining the running rules and procedures for making decisions on corporate affairs. The separation of ownership and management in modern enterprises brings agency problems to the company shareholders, and it is wildly believed that good practice on corporate governance is essential to prevent managers from taking actions by which profiteering their own benefits but compromising the interests of shareholders. This research investigates the level of companies' compliance with the corporate governance codes to find whether significant differences in corporate governance practice exist between the listed construction companies and the national leading companies in Taiwan. Further exploration focuses on the correlation between the compliance level and the industrial features. The investigation finds that: (1)Construction companies display lower levels of corporate governance compliance; (2)Construction companies display lower levels of structural board independence and respect for stakeholders; (3)Compliance levels of construction companies are correlated with the number of employees and the ownership concentration; (4)Compliance levels of the whole sample companies are correlated with the factors representing firm size, such as turnover, capital and number of employees, but are independent of profitability as well as stock price volatility. The above empirical evidence characterizes the features of corporate governance in Taiwan listed construction companies, including: (1)Large companies lurking high risk of agency problems have more willingness to conduct corporate governance and meanwhile can afford higher costs for the conduction, so that their compliance level would be higher than smaller companies; (2)Construction companies in Taiwan have higher ownership concentration, on account of the industrial tradition of family business, and therefore pay less attention to the compliance with structural board independence and respect for stakeholders. However, the conclusions indicate that further studies are essential to clarify whether the above disparities would lead to a negative cycle of corporate governance practice in construction industry. The benefits of corporate governance should unfold more evidently to convince construction companies for improving their investment environment and stimulating their healthy growth.

• 한국식품영양과학회지
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• 제26권6호
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• pp.1200-1207
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• 1997

Effects of kimchi on lipid metabolism and immune function were studied in experiments using 63mals SD rats fed 6 inds of Baechu-kimchi containing diet during 4 weeks. Three kinds of freeze dried kimchi differ in fermentation period (not fermented, 3-, 6-week-fermented at 4$^{\circ}C$) were added at 5%, 10% of the diet containing 15% lard. The levels of serum total lipid and triglyceride and the content of liver total lipid and triglyceride of all kimchi groups were lower than those of a control group. But the levels of serum and liver cholesterol is not affected by kimchi intake. The triglyceride concentration of epididymal fat pad and feces of kimchi groups were higher than those of a control group. The food efficiency ratio, epididymal fat pad weight of 3-, 6-week-fermented kimchi 10% groups were significantly lower than control and not-fermented kimchi groups. Especially 6-week-fermented kimchi groups showed adipocytes, less in number and larger in size than those of other groups. The blastogenesis of spleen lymphocytes to LPS was higher in rats fed fermented kimchi diets than rats fed control and not-fermented kimchi diet. These results suggest that kimchi stimulates lipid mobilization to epididymal fat pad and lipid excretion via feces, so lower serum and liver triglyceride concentration. The fermented kimchi stimulate the proliferation of B cell and lower the lipid accumulation in epididymal fat pad, especially kimchi fermented for 6 weeks at 4$^{\circ}C$ lower the adipose cell number.

• 한국입자에어로졸학회지
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• 제7권3호
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• pp.71-77
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• 2011

Pork belly meat and mackerel are popular meals in Korea. Although a lot of people enjoy cooking these food, there have been some reports that generated organic particles during cooking could be thereas on of lung cancer of nonsmoking housewives. In addition, some experiments show that carcinogens may be included in meat and fishes which we eat usually. For this reason, particle size and concentration in formation during cooking are necessary to figure out the relationship between particles and the diseases. Thus, we identify number concentrations and size distributions of generated nano aerosol in cooking with respect to time, hood operation, and distance between cooking and measurement locations. The maximum concentrations of nano aerosol(diameter sizes are between 10 to 700nm)are decreased after the cooking from $8{\times}10^6{\sharp}/cm^3$ to zeroth order in pork belly meat cooking, and from $3.5{\times}{\times}10^6{\sharp}/cm^3$ to zeroth order in mackerel cooking respectively. When it comes to hood operation during cooking, the detected concentrations of generated aerosols are decreased as in taking flow rate of the hood increases. In cooking pork belly meat, the reduced amount of concentration is about $3{\times}10^6{\sharp}/cm^3$ compared to no hood operation, when hood in taking flow rate is $610m^3/hr$ In mackerel cooking, reduced concentration is $6{\times}10^5{\sharp}/cm^3$ in the same condition. Also, Naphthalene and Fluorene, which are known as polycyclic aromatic hydrocarbons (PAHs), are detected in the generated aerosols during cooking.

• 한국지하수토양환경학회지:지하수토양환경
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• 제20권7호
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• pp.121-134
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• 2015

Spatial and temporal changes in algal population in Yongdam reservoir and ecological factors that induced the changes in the size and composition of algal population were investigated by monthly sampling at ten locations in the reservoir. Nutritional state of the reservoir was identified to be phosphorus-limited with nitrogen to phosphorus (N : P) ratio much greater than 17 in most samples. Algal population was dominated by three taxonomic groups, diatoms, chlorophytes and cyanobacteria. Although explosive algal growth was not observed in the summer, algal population showed transition with time of the dominant algal type from diatoms in the winter to cyanobacteria in the summer. Chlorophyta was not the dominant group in the reservoir although they maintained relatively stable number of cells in the reservoir and showed increase in population from March to May. The application of statistical methods revealed that the factors inducing changes in cell number of each group were water temperature for diatoms and cyanobacteria and phosphorus concentration for chlorophyte. Fluctuation of cyanobacterial population was mainly observed near the inlet of tributaries while diatoms showed higher variation inside the reservoir.

• Journal of Oral Medicine and Pain
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• 제8권1호
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• pp.33-41
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• 1983

The authors observed the ultrastructure of oral leukoplakia simplex of gingiva, buccal mucosa, tongue and alveolar ridge. For the purpose of clearly defining the lesions under investigation in this study, leukoplakias were cinsidered to be any white patches on the oral mucous membranes that could not be removed by rubbing and could not be classified clinically or microscopically as another diagnosable disease. The tissue to be examined were embedded in paraffin for light microscopic study. The tissue to be examined under the electronomicroscope were fixed in 2.5% glutaraldehyde in 0.1M cacodylate buffer and 1% osmic acid in 0.1M cacodylate buffer, dehydrated with guaded alchol, and treated with propylene oxide, and embedded in Epon.Ultrathin sections were obtained by LKB III ultrotome, stained with uranyl acetate/lead citrate, and examined with Corinth 500EM. The results were as follows : 1. Epithelium of leukoplakia consisted of stratum basale, stratum spinosum, stratum granulosum and stratum corneum. 2. There was hyperorthokerotosis or hyperparakeratosis. 3. Granular cells contained a lot number of membrane coating granule showing lamellar structure, clearing ot codensation, and a lot of keratohyaline granule varied in size. 4. An increased concentration of tonofilaments and an increased number of desmosomes were found in the stratum spinosum. 5. Basal lamina generally showed its continuity, but in some locatoins, its interreption and multiplication appeared.

• 산경연구논집
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• 제11권4호
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• pp.31-38
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• 2020

Purpose: At a time when the distribution industry is dominated by capital and technology, win-win growth among businesses groups (BGs) in wholesale market is becoming a social issue. Therefore, through analysis of market growth, market concentration (MC) and market power (MP), we want to identify the structure of the wholesale market and the competitiveness of the BGs in terms of market share (MS), sales-profit ratio (SPR), and labor productivity (LP) to explore the possibility of win-win growth. Market situation: Wholesale and Retail sales ratio (W/S) continues to increase, which also means inefficiency in distribution channels or opportunities in wholesale markets. Wholesale sales have grown 8.3 percent annually over the past 15 years, while the number of companies and workers has declined since 2017, which is why some restructuring is believed to begin in the wholesale industry. In terms of MC and MP, the growth potential of SBG can be found in FCB, ARM, FBT and CME BTs. Methodology and data: Through ANOVA and Regression Analysis, the 2015 Economic Census Data of KOSTAT was analyzed. Results: The results of ANOVA show that statistically significant SBG has a larger MS than LBG. The SPR was not different among BGs. LP is higher for LBG than for other BGs. Regression results show that the employment weight (EW) and the company size (SC) have positive effects on the MS, but the company weight (CW) and employment size (SE) have negative effects. In the case of SPR, the CW is positive and the EW is negative. In addition, LP appears to be more positive as SC in the BGs is larger. Conclusions: Although there is sufficient potential for SBG in the wholesale market, there is a problem that needs to increase LP. Therefore, the SBG needs to restructure in terms of number of companies and SC to improve the efficiency of employment. In terms of MC and MP, the SBG looks for possibilities in FCB, ARM, FBT and CME BTs. In addition, SBG that seeks higher returns with human services rather than simple sales is found to be competitive in the HHG, MES and CME BTs.

• 원예과학기술지
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• 제16권1호
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• pp.40-41
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• 1998

본 연구는 왜화제 uniconazole처리가 심비디움 Pine Clash 'Moon Venus'와 Green Sour 'A One' 의 생장 및 개화에 미치는 영향에 대해서 조사하였다. 두 품종 모두 uniconazole의 처리량이 많아질수록 왜화효과가 강하게 나타났으며 'Moon Venus'보다 'A One'의 생장억제가 현저하였다. 화서장은 uniconazole 5g 처리에 의해서 'Moon Venus'의 경우 18.4%, 'A One'의 경우 15.3% 억제되었다. 개화시기, 화서수, 소화수, 하악편의 크기 등은 uniconazole 처리에 의해서 약간의 변화는 있었지만 무처리와 큰 차이는 없었다. 이상의 결과로부터 uniconazole 처리는 심비디움의 영양생장기관인 잎의 생장을 억제하는데 효과적인 왜화제이나 고농도(5g) 처리에서는 화서의 생장까지 억제하여 품질의 하락을 초래할 수도 있기 때문에 적정 처리량은 1g 정도로 판단되었다.

• 한국자동차공학회논문집
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• 제18권4호
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• pp.140-146
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• 2010

An experimental study was carried out to investigate the emission characteristics for various alternative fuels in a 2.0 liter 4-cylinder turbo-charged diesel engine. The conventional diesel fuel, neat GTL (Gas to Liquid), blends of diesel and biodiesel(BD20), and blends of GTL and biodiesel(G+BD20 and G+BD40) were applied, and their emission characteristics were compared at various steady-state engine operating conditions. A noticeable reduction of exhaust emissions compared to conventional diesel fuel, except for NOx emission, was observed for G+BD40, where there is a maximum 30% averaged reduction for gaseous emissions (THC and CO) and 70% for PM mass concentrations. When comparing PM size distributions for biodiesel blended fuels, the PM number concentration in accumulation mode, where the diameter of PM is greater than 50 nm, decreased due to additional oxygen content in the biodiesel fuel; in nucleation mode, where the diameter of PM is less than 50nm, there was a slight increase or decrease in the PM number concentration depending on the amount of oxygen available in the combustion chamber.

• 한국콘텐츠학회논문지
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• 제21권8호
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• pp.69-78
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• 2021

디지털 기술발전과 더불어 극장이 아닌 디지털 온라인 매체에서의 영화 수요와 공급이 지속적으로 증가하고 있다. 본 연구는 극장에 비해 다양한 영화가 상영되는 디지털 온라인 영화시장의 수요 집중화 경향을 분석하고자 한다. 2013년 1월부터 2019년 12월까지 TV VOD 자료에 대한 실증분석을 통해 다음의 결과를 확인하였다. 첫째, 극장개봉작 1,137편의 영화에 대한 분석을 통해 디지털 온라인 매체인 TV VOD 관람 수요에 비해 극장 관람 수요의 집중도가 상대적으로 더 높음을 확인하였고 이러한 차이가 통계적으로도 유의하게 나타났다. 둘째, TV VOD 수요 집중도 추이를 살펴보면, 시장에 공급되는 작품편수가 증가함에 따라 절대적 롱테일 지수에 해당하는 독립·예술영화(틈새 상품) 수요도 증가하는 추이를 보이지만 상대적 롱테일 지수인 독립·예술영화 수요 비중과 상위 1% 영화의 수요 비중의 경우 증가 또는 감소 추이가 뚜렷하게 나타나지 않았다. 셋째, TV VOD 수요 집중도와 TV VOD 시장규모 간에 통계적으로 유의한 관계가 있다고 보기 어려웠다. 본 연구는 우리나라의 디지털 온라인 영화시장의 특징을 파악할 수 있는 실증적 결과들을 제시하였다는 점에서 유용성을 가질 것이다.