• 한국물환경학회지
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• 제21권5호
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• pp.448-457
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• 2005

The conventional activated sludge processes were operated as a combined organic substrate removal and nitrification. So, it was necessary to provide with oxygen for both carbon and ammonia removal. But, in the BNR processes, nitrification is separated from carbon removal that causes fast ammonia oxidation and reduced oxygen demands. And most of the substrate is utilized by denitrification organisms and phosphorus accumulating organisms. with these appearances, mathematical model for BNR processes different from IWA ASM can be simplified and applied. In this study, it was performed that the existing equations as McKinney model, nitrification model published by U.S. EPA and oxygen demands from stoichiometry and the relationship between NUR and OUR were applied to full-scale BNR processes and the results were compared with the measured. and it is possible to make out the optimum design parameter from those equations.

• 상하수도학회지
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• 제11권2호
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• pp.76-93
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• 1997

Activated carbon is widely used for the treatment of water, wastewater and other liquid wastes. Biological activated carbon (BAC) process is water and wastewater treatment process developed in the 1970's. In addition to activated carbon adsorption, biodegradation organic pollutants occurs in the BAC bed where a large amount of aerobic biomass grows. This results in a long operation time of the carbon before having to be regenerated and thus a low treatment cost. Although the BAC process has been widely used, its mechanisms have not been well understood, especially the relationship between biodegradation and carbon adsorption, whether these two reactions can promote each other or whether they just simultaneously exist in the BAC bed. Also, the phenomenon of bioregeneration has been confused that previously occupied adsorption sites appear to be made available through the actions of microorganisms. And that, because biological process is influenced by low temperature, the mechanism of the BAC process is also effected by temperature variation in our country of winter temperature near the freezing point. Therefore, the objective of this study examines closely the mechanism of the BAC process by temperature variation using phenol as substrate. From this study, biological activated carbon is good substrate removal better than non adsorbing materials (charcoal, sand) as temperature variation, especially low temperature(near $5^{\circ}C$).

• 상하수도학회지
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• 제22권2호
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• pp.245-250
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• 2008

Adsorption experiment was carried out to find the adsorption capacity and characteristics of heavy metals(Cd, Pb) onto soil and mixed soil with food compost. Result showed that mixed soil having higher organic content adsorbed more heavy metal than soil, indicating that food compost can be used effectively to prevent soil pollution. Linear adsorption isotherm which adopted to find the adsorption characteristics was used to calculate Retardation Factor(R). The value of Retardation Factor(R)s of Pb and Cd in mixed soil, found as 34.54, 24.42 respectively, are higher than those in soil which were found as 4.64, 3.67, respectively. The value of Retardation Factor(R) using Freundlich adsorption isotherm could be presented by the functions of concentration and showed similar result as the linear one. But Freundlich adsorption isotherm showed higher relationship than linear one and the retardation factor(R) from freundlich adsorption isotherm was thought as more effective method to assess adsorption capacity because it could reflect gradient and intercept of the isotherm.

• 상하수도학회지
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• 제26권1호
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• pp.47-54
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• 2012

This study analyzed influence factors and the correlation among pollutants which affect occurrence of leaked pollution based on the long-term runoff flow and water quality investigation results to understand the characteristics of highway rainfall runoff pollution load. According to the result of correlation analysis on TSS (Total Suspended Solid) concentration, anteceded dry days, rainfall intensity, traffic volume and etc. as major influence factors of highway rainfall runoff pollution loads, the correlations were weak or scarce in most items. These results might be attributed that runoff pollutant concentration changes vary severely on changes of rainfall intensity and rainfall duration within rainfall and it is affected by disturbances of vehicles and street cleaning and etc. as characteristics of the highway. While Cu, Fe and Zn which are discharged with high concentrations out of heavy metals showed high correlation with particulate matter, organic matter(COD), nutrient(TN, TP), Ni and Pb showed relatively low correlation in a correlation evaluation by pollutant. Significant correlation with traffic volumes was not shown and TSS concentration even decreased in accordance with increase of the traffic volume. In the comparison with precedent studies, it was considered necessary additional analysis of the effects of rainfall section analysis, road type, disturbances of surface contaminants by vehicles, rainfall and climate conditions, surrounding terrains etc.

• 가정과삶의질연구
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• 제28권2호
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• pp.51-62
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• 2010

This study aims to find out how childhood teachers recognize the characteristic of children, family and community resilience and there are any relationships between children, family and community resilience that teachers recognize. In this Study, 280 teachers working in kindergarten and nurseries in Busan and Ulsan Metropolitan City were subjected to questionnaire survey. Data obtained were analyzed by using frequency, percentage, average, standard deviation, one-way analysis of variance, correlation analysis and factor analysis of SPSS 12.0 statistical program. The results were as follow: First, childhood teacher recognized optimism and positiveness as characteristics of childhood resilience. Second, childhood teacher recognized family cohesion and role stability as characteristics of family resilience. Third, childhood teacher recognized community service and support system as community resilience. Fourth, childhood teacher recognized illustrates mutually organic relationship amongst them, childhood resilience was found to be more closely related to family resilience.

• 한국의상디자인학회지
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• 제15권4호
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• pp.157-173
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• 2013

In the pleats of the statue in the ancient Greece, a vivid expression is included about clothing, which has organic relationship with a human body. This study examined about diverse expressions of pleats that were shown in the Greek sculpture, based on understanding about a pleat meaning and function, and clothes. As a result, the clothes, which were shown in the statue in the ancient Greece, were reflecting spirit and fashion of the times. The pleats, which were expressed in clothing, are closely related to a human body and simultaneously are those that a sculptor showed own creative intention in a work by reflecting a historical demand, thereby having become an important element of dominating the image in the whole clothing. Also, a change and development in expression were being progressed according to a flow of each period. Amidst what expressiveness based on lines are excellent, the unity and the dynamic formative characteristic were forming the mainstream. The design-based elements related to these characteristics are judged to possibly give many inspirations to designers in the modern fashion design sphere, which is mixed diverse styles, and are considered to be able to be helpful even for establishing newer and more creative design.

• 한국산업보건학회지
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• 제21권4호
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• pp.193-200
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• 2011

Objectives: Blood lead and hyperhomocysteinemia have been found to be associated with cardiovascular disease. The objective of the present study was to assess the relationship of lead biomarkers on plasma homocysteine and blood pressure. Methods: To evaluate the effect of lead biomarkers including blood lead on plasma homocysteine and blood pressure in retired lead workers, 66 retired lead workers without any occupational exposure to organic solvent, mercury and arsenic were agreed to participate this study. For the control subjects 42 controls were recruited from same area of retired lead workers with consideration of demographic characteristics. Results: The mean levels of blood lead and ZPP of retired lead workers were significantly higher than control group. There were positive significant correlations between blood lead and plasma homocysteine, also systolic and diastolic blood pressure. The multiple linear regression analysis also reveled that plasma homocysteine was significantly associated with blood lead after adjusting for age, gender, body mass index, lead exposure, smoking and drinking. Diastolic blood pressure was significantly associated with blood lead, plasma homocysteine, and total cholesterol; whereas, systolic blood pressure was significantly associated with plasma homocysteine only. Conclusions: Blood lead showed significant association with plasma homocysteine and blood pressure even after more than mean 10 years from their retirements.

• 한국환경과학회지
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• 제7권3호
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• pp.301-310
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• 1998

Recently, bathes have been suspected to an Important source of indoor exposure to volatile organic compounds(VOCs). Two experiments were conducted to evaluate chloroform exposure and corresponding body burden by exposure routes while bathing. Another experiment was conducted to ekamine the chloro- form dose during dermal exposure and the chloroform decay In breath after dermal exposure. The chioroform dose was determined based on exhaled breath analysis. The ekamine breath concentration measured after normal baths (2.8 Vg/$m^3$) was approxidmately 13 tomes higher that measured prior to normal bathes (0.2 ug/$m^3$). Based on the means of the normalized post exposure chloroform breath concentration. the dermal exposure was estimated to contribute to 74% of total chloroform body burden while bathing. The Internal dose from bathing (Inhalation plus dermal) was comparable to the dose ostimated Srom dally water Ingestion. The rusk associated 10 a weekly, 30-min bath was estimated to be 1 x 10.5, while the rusk firom dally Ingestion of tap water was to be $0.5{\times}0^{-5} for 0.151 and 6.5{\times}10^{-5}$ for 2. 0 1. Chloroform breath concentration Increased gradually during the 60 minute dermal exposure. The breath decay after the dermal exposure showed two-phase mechanism, with early raped decay and the second slow decay. The mathematical model was developed to describe the relationship between water and air chloroform concentrations, with $R^2$ : 0.4 and p<0.02.

• 한국의류산업학회지
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• 제14권3호
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• pp.430-437
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• 2012

This study analyzed the sensibility of eco-friendly fabrics for college students and investigated their attitude on environmental problems, trust reliability onto eco-apparel products, and their purchase state. We tested 6 eco-friendly fabrics (recycled polyester, organic cotton, green tea, charcoal, bamboo, and nettle) through a survey using the Likert scale of 12 polar sensibility words. Most fabrics showed feelings that were smooth, natural, female, and country these were followed by fashion, cheap, functional, sustainable, warm, and vintage. In addition, nettle fabric showed 'rough' feeling, and recycled polyester fabric showed an 'artificial' feeling. Correspondence analysis showed the distance and direction between fabric types and sensibility words with a 2D diagram where the X axis was named with 'Soft <-> Hard' and Y axis was with 'Environmental <-> Manmade' to represent the relationship between fabric types and the sensibility words. According to the results of the multiple regression analysis, the cognition level of the consumer for environmental problems was found to be the most influential variable on the loyalty purchase of eco-friendly products; however, the trust reliability level of consumer onto eco-friendly apparel products was found to be the most influential variable on the conditional purchase of eco-friendly apparel products.

• 지구물리와물리탐사
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• 제7권3호
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• pp.184-190
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• 2004

불포화대 토양특성 분석을 목적으로 토양단면의 고해상도 영상을 얻을 수 있는 전기비저항 토모그래피를 적용하였다. 전극설치 지점에서 심도별로 채취한 토양시료를 대상으로 토양 공극수의 전기전도도, 수분함량, 이온함량을 측정한 결과, 토양특성과 전기비저항 토모그래피 결과의 상관성이 토성별로 선형적인 관계가 나타남에 따라 전기비저항 토모그래피 결과를 보다 효과적으로 해석할 수 있었다. 따라서 불포화 토양층을 대상으로 한 전기비저항 토모그래피를 이용하여 시추공 사이의 토양특성을 파악할 수 있으며, 토양의 산도, 유기물 함량 등의 간접적 평가가 가능할 것으로 판단된다.