• Applied Chemistry for Engineering
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• v.10 no.4
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• pp.523-530
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• 1999

Acrylic pressure-sensitive adhesive has been made utilizing organic solvents, but nowadays it is made by solvent-free system due to environmental problems. In this study, emulsion polymerization were carried out at $40^{\circ}C$ with methacrylic acid(MAA), n-butyl acrylate(n-BA) and 2-ethylhexyl acrylate(2-EHA) as monomers in the presence of anionic(sodium dodecyl sulfate, SDS) and nonionic(ethylene oxide types) surfactant mixtures. The overall conversion of the polymerization reaction in a mixed surfactant system was found to be higher than that in a single surfactant system. Emulsion stability in mixed or anionic surfactant systems was found to be over 12 week, which was better than that in nonionic surfactant system. Emulsion particle size decreased as surfactant content increased. The Tg and molecular weight of emulsion polymer were inependent of the type, the amount and the mixing ratio of surfactant. Based on the results of stability and peel strength, the optimum nonionic surfactant ratio in total 4 g of surfactant mixture systems is found to be 40~60% by weight where the nonionic surfactant has 50 ethylene oxide groups and 16~18 carbon atoms in hydrophobic alkyl chain.

• Journal of Korean Society of Transportation
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• v.18 no.6
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• pp.7-17
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• 2000

The Purpose of this study is to test the effectiveness of Special Transportation Management Zone system (TZ) when it is applied to Dongdaemoon commercial zone located in downtown Seoul. The study consists of two Parts ; the legal components of TZ and the case study on Dongdaemoon district. The case study includes the analysis of current traffic situation on the study zone, the design of implemention alternative for each component of TZ, the framework of impact analysis system, and the analysis results. The study finds, if 2,000 won mandatory parking fee on drivers parking in the buildings only with over 10 parking spaces and over 3.000$m^2$ in floor area, strong illegal parking enforcement, and Pro-hibition of parking passenger cars whose last digit plate number matches with the last digit of date, are implemented in the zone simultaneously, the traffic speed increases to 20.56km/h which is above the target set in the zone. In conclusion, we find that TZ2 can be an effective tool relieving traffic congestion in Seoul, and that it is necessary for introducing TZ in Seoul that relevant laws should be revised and expecting problems should be overcome.

• Journal of agricultural medicine and community health
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• v.20 no.1
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• pp.25-30
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• 1995

To investigate the response rate for family examination and the morbidity of family members, we reviewed the medical records of 1,525 tuberculosis patients at health center of Sunsan county in Kyungpook province from January 1981 to December 1990. The response rate for family examination in the first period(1981-1985) was 20.0%, and that in the second period(1986-1990) was 78.8%. The response rate for family examination was rapidly increased with the year. The kinship between the tuberculosis patients and examinees was very closely related with the response rate of family examination. The radiological finding was closely related with rate for family examination was 63.0% in the children of patients, 28.9% in wives or husbands of patients, 28.8% in other relatives and 19.9% the morbidity rate of family examinees. The severe the radiological finding, the higher the tuberculosis morbidity rate of family examinees. The prevalent rates of family examinees were 6.2% in parents, 4.3% in wives or husbands, 1.1% in children, and 1.5% in other relatives of parents. The results of this study suggest that the response rate for family examination should be increased especially for the old people, such as parents of tuberculosis patients.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.2
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• pp.179-185
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• 2010

To evaluate the antioxidant and antitumor potential of a newly bred rice, Hiami (Suweon-511), total polyphenol content, $\gamma$-oryzanol content, radical scavenging activities, and antitumor activities were measured (control: Ilpum). Total polyphenol contents were 6.31 and 3.75 mg/g for unhulled (UHR) and hulled rice (HR) of Hiami, which was higher than that of Ilpum (5.66 and 3.47 mg/g). The $\gamma$-oryzanol contents were 33.53 and 39.47 mg/100 g for UHR and HR of Hiami, which was higher than that of Ilpum (24.33 and 28.68 mg/100 g). DPPH radical, hydrogen peroxide, superoxide radical and hydroxyl radical scavenging activities of 70% ethanol extracts of Hiami were higher compared to Ilpum, and UHR was higher than those of HR. Antitumor activities of the 70% ethanol extracts of Hiami and Ilpum were increased with a dose-dependent manner. The extracts of Hiami have higher activities of antitumor activities on gastric and breast cancer cell lines compared to other cancer cell lines, and Ilpum has higher activities of antitumor activities on colon and liver cancer cell lines.

• Korean Journal of Human Ecology
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• v.18 no.6
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• pp.1349-1361
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• 2009

The present study was designed to analyze the relationship of dietary behavior change and nutrient intake status owing to a depression degree for 143 people over 65 years old living in Echeong and Hansan islands area, South Korea. The depression degree was classified into non depression, minor depression and depressive disorder groups using. The Center for Epidemiological Studies-Depression (CES-D) scale for 143 subjects. The results are as follows; the depression degree significantly made differences according to sex (p<.001), marital status (p<.05), self-related economic status (p<.001) and living expenses (p<.05). The stage of dietary behavior according to the depression degree was as follows; the non depression group was 57.6%, the minor group was 46.8% and the depressive disorder group was 27.1% of the subjects. The intake frequency of the cereal group (p<.05) and fruit group (p<.01) was significantly different among food group intake status owing to the depression degree. Mean adequacy ratio(MAR)[13], MAR[10], and MAR[4] of the depressive disorder group were significantly lower than that of the non depression and minor depression groups. Each average of MAR[13], MAR[10], and MAR[4] for the subjects were $0.68{\pm}0.2$, $0.67{\pm}0.2$, and $0.55{\pm}0.2$. Concerned about the nutrients over 1.0 index of nutritional quality(INQ) 8 nutrients of protein, Phosphorous, iron, zinc, vitamin A, vitamin $B_6$, niacin and vitamin C belonged to the non depression group. Additionally, 6 nutrients of protein, Phosphorous, iron, zinc, vitamin $B_6$ and niacin were included for minor depression and depressive disorder groups.

• Journal of Korean Society of Forest Science
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• v.95 no.4
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• pp.423-428
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• 2006

This study was carried out to investigate the early growth of revegetation plants by microorganisms in slope of forest road in Jinju area. The results were summarized as follows; The chemical properties of forest soil were changed by microorganisms. Soil pH, organic mater content, concentrations of total nitrogen, available phosphorus, exchangeable cations and CEC in treated plot were increased more than those of controlled plot in the surface soil. It showed that the availability of nutrients including nitrogen and phosphorus was increased by an application of microorganisms in the soil. The coverage rates showed statistically significant differences between plots (p<0.05). The germination rates of woody plants were better in treated plot than in controlled plot. The results indicate that the application of microorganisms would be significantly contributed for the early growth of revegetation plants on slope of forest road.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.47-47
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• 2011

하도 내 수역이 식생으로의 천이가 진행되고 최종적으로는 육상 식물들이 활착하게 되는 육역화 현상은 하도의 수리학적 문제 및 환경생태적 측면에서 큰 문제를 발생시킬 가능성을 내포하고 있다. 최근 하천복원의 필요성이 강조됨에 따라 물골공법 및 국부세굴 유도형 공법 등 실용성을 포함시킨 다양한 하천 복원공법이 제시되고 있다. 물골공법은 자연적인 물골형상에 의한 유사퇴적방지, 홍수시 유속저감 및 생물서식처를 조성하는 하상 생태복원 공법을 의미하며, 본 연구에서는 수리모형실험 및 3차원 수치모의를 이용하여 다양한 하도육역화 방지 공법 중 물골공법의 효과 및 적용성을 검토하였다. 물골공법의 특성 중 유사퇴적방지의 효율성 분석을 위해 부정류(unsteady state)상태에 대해 연구를 수행하였으며 홍수 이후 수위하강시 고수부지 및 물골 주변에서의 흐름특성을 재현하였다. 수위하강 모의를 위해 임의의 수위하강시간을 선정하여, 수위하강이 진행되는 시간( )을 각각의 수위하강시간으로 무차원 화한 후 무차원된 시간(t/�� )에 따른 흐름특성을 비교 분석하였으며 모의 및 분석결과, 수위하강시간이 80초 이상일 경우 주요 지점에서의 유속의 변화는 무차원된 시간에 대하여 일치하였으며 수리모형실험 및 수치모의에 적용할 수위하강시간으로 선정할 수 있었다. 물골 전구간에 대한 부정류 실험을 위해 LSPIV(Large-Scale Particle Image Velocimetry)장치를 이용하여 수위하강에 따른 물골주변의 흐름특성을 관측하였으며 3차원 수치모의를 통해 검증하였다. 실험 분석결과, 수위하강에 따라 고수부지 위로 흐르는 유수가 물골 내부로 유입되어 물골을 따라 흘러 물골 합류부로 이동하는 것으로 나타났으며, 이는 홍수시 유수와 함께 떠다니는 부유사(suspended load)가 물골로 유입되어 물골 합류부로 이동하므로 물골의 유사배제 가능성을 판단할 수 있었다. 또한 물골의 유사배제능력을 평가를 위해 실험을 통하여 산정된 최대 및 최소 마찰속도(U )와 유사이동 한계곡선을 이용하여 물골의 통한 배제 가능한 유사의 입경을 분석하였다. 분석결과, 최소 2mm에서 최대 4mm로 나타났으며 이 입경 이하인 유사에 대해서는 퇴적되지 않고 물골을 통하여 배제될 수 있을 것으로 예상되었다. 본 연구 결과 물골공법 적용시 수위하강에 따라 물골에서 하도방향으로 유사의 수세(flushing)효과가 나타났으며 유사의 부상 및 이송이 효과적으로 발생하여 고수부지 내 유사퇴적 방지가 효과적인 것으로 판단되었다. 추후 다양한 형상의 물골에 대한 능력검토가 보완된다면 물골설계지침 제안을 위한 자료로 활용 가능할 것이다.

• Korean Journal of Microbiology
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• v.45 no.2
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• pp.133-139
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• 2009

A nutrient-concentrating system was operated to retrieve total phosphorus efficiently from a non-point pollution source. Attached bacteria were expected to play an important role in the system. Phosphorous was concentrated by formation of bacterial biofilms on rubberized coconut fiber media of the system. While concentration of total phosphorus (TP) ranged merely 0.12~0.35 mg/L in the stream water, TP levels in pore water and the media were 0.45~0.86 mg/L and 40.91~242.71 mg/kg, respectively. Total bacterial number (TBN) ranged $0.3\sim2.3\times10^6$ cells/ml in stream water, $0.4\sim4.4\times10^6$ cells/ml in pore water and $0.8\sim1.9\times10^9$ cells/g in media. There was a close correlation between TP and TBN. Based on band profiles in DGGE analyses, bacterial communities in the media were different from that in the stream water. Clostridium spp. were abundant in the stream water while Aquabacterium spp. were dominant species in early stages of biofilm formation in the media. The genera predominant in matured biofilms of the media were Clostridium and Enterococcus.

• KSBB Journal
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• v.19 no.1
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• pp.12-16
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• 2004

Recently the measurement of biophoton emission has attracted increasing attention in the study on physiological state of biological systems. We report the measurements of biophoton emission from the mouse fatty liver induced by carbon tetrachloride, CCl$_4$. The hepatotoxin, CCl$_4$ in olive oil, was injected intraperitoneally into two groups of ICR mice which were made of 6 mice in each group. The control groups corresponding to the treated groups were prepared with the injections of olive oil only. After the injections, livers of two groups were extracted and measured biophoton emission in 24 hours and 72 hours later, respectively. We also extracted the plasma in the blood and measured the transaminase activity. Results show that biophoton emission from the livers in 24-hour treated group is 69.3${\pm}$21.2 counts/min/$\textrm{cm}^2$, which is two times more larger than that in 24-hour control group, 29.5${\pm}$5.9 counts/min/$\textrm{cm}^2$ Biophoton emission from the livers in 72-hour treated group is 37.0${\pm}$14.8 counts/min/$\textrm{cm}^2$. These biophoton results correlate with those of the biochemical assays. We conclude that biophoton emission can be used as a biomarker of mouse fatty liver induced by CCl$_4$.

• Journal of the Korean Association of Geographic Information Studies
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• v.6 no.2
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• pp.22-32
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• 2003

The purpose of this study is to analyze soil erosion quantity of a basin by using DEM, soil map and landuse map and to find a soil erosion hazard zone in a basin based on this data. In this study, RUSLE was used to analyze soil loss quantity and the research area chosen is Mushim stream which branches off the Geum river. This study used a mean annual precipitation of Cheongju Meteorological Observation was used as a hydrological data and DEM, the detailed soil map(1/25,000), the landuse map collected respectively from Ministry of Environment, National Institute of Agricultural Science and Technology and Ministry of Construction and Transportation. The subject map was drawn to analyze soil erosion hazard zone by using the above data and maps. According to the results of the analysis, a lot of soil loss shows in a bare area. In case of a forest, a slope has a lot of influence on soil loss. The integration and analysis of the above gave the result that $193,730.3m^2$corresponding to 8.5% of the places of which the slope is over 20 degree in a bare area was found to have a higher chance of soil erosion.