• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.4
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• pp.380-391
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• 1993

The experimental study was made to propose the treatment method of wastewater in the high-density fish culture system. The BOD to COD ratios of effluents were almost same to 0.65 in the eel-farm, but were various in the farm rearing together with tilapia etc. A BOD rate curve of the eel-farm effluent could be described mathematically by the equation, $BODu=14.1(1-10^{-0.222t})+30.9(1-10^{-0.035(t-8)})$. Nitrification in Biological Fluidized Bed(BFB) system to treat the fish-farm wastewater could be reduce ammonium level up to $65{\sim}79\%$ when ammonium loading rates were between 0.014 and 0.075g $NH_4/g$ BVS-day. Nitrification efficiency was decreased by organic matters in the wastewater when ammonium loading was low(0.014 g $NH_4/g$ BVS-day). T-N removal ratios were decreased to increase loading in denitrification process, because of low C/N ratio. Based on much higher biological mass concentrations, BFB system takes many advantages of a practical viewpoint, such as stability of treatment efficiency and reduction of necessary site area for the facility, as compared with conventional treatment systems.

• Journal of Soil and Groundwater Environment
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• v.7 no.2
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• pp.63-71
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• 2002

The authors selected the modified soil method, and then performed the geotechnical and environmental laboratory test, and evaluated whether the modified soil liner could be accepted as a barrier layer in landfill. Unlike the results of the natural soil(CL), those of the hydraulic conductivity test of stabilized soil met the standard value. According to these results, the optimal mixing ratio of a mixture(cement : bentonite : stabilizing agent) was 90 : 60 : 1 with mass ratio(kg) for 1㎥ with soil, and it was possible to use poor quality bentonite. B\circled2 because of a little difference from results with high quality bentonite. B\circled1. The Cation Exchange Capacity(CEC) of the modified soil was increased about 1.5 times compared with the natural soil; however. the change of CEC with a sort of additives was not detected. In order to observe the change of the chemical components and crystal structures, the natural and the modified soils with the sorts of additives were measured by the XRF(X-Ray Flourescence Spectrometer) and SEM, but there was no significant change. The artificial leachate with the heavy meals ($Pb^{2+}$ , $Cu^{2+}$, $Cd^{2+}$ Zn$^{2+}$ 100mg/L) was passed through the natural soil and modified soils in columns. In the natural soil, Cd$^{2+}$ and $Zn^{2+}$ were identified, simultaneously the pH of outflow was lower, and then came to the breakthrough point. The removal efficiency of the natural soil was showed in order of following : $Pb^{2+}$ ≒$Cu^{2+}$ > $Zn^{2+}$ > $Cd^{2+}$ On the other hand, modified soils were not showed the breakthrough condition like the result of the natural soil. The modified soil with the lower quality bentonite, B\circled2(column3) was more stable with respect to chemical attack than that with the higher bentonite, B\circled1(column2) because the change range of outflow pH in columns was less than that of outflow pH in column2. In addition, the case of adding the stabilizing agent(column4) was markedly showed the phenomena.ena.

• Food Science and Preservation
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• v.16 no.2
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• pp.179-185
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• 2009

To develop an Enoki mushroom packaging method, mushrooms were stored at $1^{\circ}C$ for 12 days after passive MAP packaging(PM), vacuum packaging(VM), and gas flushing packaging(AM), after investigation of film thickness influences on respiration rates and gas compositions(LDPE films 20, 40, and 60 m in thickness were tested). Enoki mushrooms had respiration rates of 26.4 mL $CO_2/kg/hour$ at $0^{\circ}C$, 80.0 mL $CO_2/kg/hour$ at $10^{\circ}C$, 130.9 mL $CO_2/kg/hour$ at $20^{\circ}C$, and 130.9 mL $CO_2/kg/hour$ at $30^{\circ}C$. A film thickness of 20 m was chosen for further tests to maintain the oxygen concentration above the minimum growth level; the thinnest film offered a higher gas transmittance rate than did the thicker films. No anaerobic respiration was evident over 12 days of storage using any packaging method, with the exception of VM. AM, using a high concentration of $CO_2$, restricted respiration rate. Mushrooms packaged using the VM method showed the greatest weight loss and extent of discoloration among the packaging methods tested, followed by AM mushrooms using 50% $CO_2/10%\;O_2/40%\;N_2$. Mushrooms packaged by the VM and PM methods developed a serious off-flavor after 2 days of storage, and a high stipe elongation rate after 5 days of storage, respectively. However, AM using 50% $CO_2/10%\;O_2/40%\;N_2$ of various gas ratios tested, allowed Enoki mushrooms to be maintained for up to 12 days without development of off-flavor, discoloration, or moldiness.

• Journal of the Korea Organic Resources Recycling Association
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• v.10 no.1
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• pp.87-95
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• 2002

The slow degradation rate of sludge in anaerobic digestion is due to rate-limiting step of sludge hydrolysis. To upgrading of sludge hydrolysis and biodegradabiliry, the pre-treatment had been carried out using acidlc (pH 1.5, 3, 4, 5) and alkaline (pH 9, 10, 13), thermal (50, 100, 150, $200^{\circ}C$), and ultrasonic treatment (400W, 20kHz, 15, 20, 25, 30, 40, 50, 60, 90min). In the best conditions of each treatment, the Soluble SCOD Ratio(%)of treated/untreated sample were increased 102% in acid (pH5), 986% in alkali (pH 13), 595% in thermal ($200^{\circ}C$) and 1123% in ultrasonic (35min) treatment. As the result, the ultrasonic treatment was most effective, followed by alkali, thermal, acid treatment. In the effects of total gas productivity in vial test, the thermal ($200^{\circ}C$) pre-treatment was the highest, followed by thermal ($150^{\circ}C$), ultrasonic (90min), alkaline (pH 9), and ultrasonic (50min). We compared untreated samples and the most efficient pre-treatment samples(at $200^{\circ}C$, for 30min) on gas productivity with changes of HRT in continuous experiments IN thermal treated samples were 2.5 times in SCOD, 2 times in soluble protein and 3.3 times high in soluble carbohydrate than untreated ones. In gas productivity, the thermal treated samples were average 2 times high than untreated ones. And HRT 7 days was most effective. followed by HRT 10, HRT 15 days. But The gas productiviry of HRT 2.5 days was less than untreated, the reason of low gas productivity was come from high organic acids accumulation within reactor.

• Journal of dental hygiene science
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• v.16 no.3
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• pp.193-199
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• 2016

The objective of this study was to investigate the relationship between health-risk factors and oral health in Korean adolescents. This cross-sectional study was based on the 9th Korea Youth Risk Behavior Web-Based Survey (2013). The final participation rate in the survey was 96.4%. of a Total of 72,435 adolescents (age, 12~18 years) who had participated in the survey, 66,951 adolescents (33,777 boys and 33,174 girls) were selected for analysis, after excluding those with missing data. The key variables were oral health factors (one or more of the six oral symptoms), general characteristics (five factors), and health-risk factors (five factors). After adjusting for the general characteristics, frequency analysis, ${\chi}^2-test$ using PASW Statistics ver. 18.0, and logistic regression analysis were performed to understand the effects of health risk-factors on the oral symptoms experienced by the study subjects. Subjects who answered 'Yes' for alcohol consumption had a 1.33 times higher risk of experiencing oral symptoms. Further, subjects who smoked were at a 1.2 times higher risk of experiencing oral symptoms. With regard to internet use, the risk of experiencing oral symptoms was 1.25 times higher for subjects who used the internet for 7 hours or more than for those who used it for less than 1 hour. Compared to those subjects who had not experienced violence in school, the odds ratio of subjects who had experienced it 3~4 times was 1.54-fold higher. The study found that health-risk factors were associated with oral symptom experience. Therefore, programs to understand health-risk factors and interventions should be developed for Korean adolescents and provided on a regular basis along with oral health education.

• Geophysics and Geophysical Exploration
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• v.9 no.1
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• pp.129-138
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• 2006

Helicopter-borne aeromagnetic surveys at two different times separated by three years were conducted to better understand the shallow subsurface structure of the Vulcano and Lipari volcanic complex, Aeolian Islands, southern Italy, and also to monitor the volcanic activity of the area. As there was no meaningful difference between the two magnetic datasets to imply an apparent change of the volcanic activity, the datasets were merged to produce an aeromagnetic map with wider coverage than was given by a single dataset. Apparent magnetisation intensity mapping was applied to terrain-corrected magnetic anomalies, and showed local magnetisation highs in and around Fossa Cone, suggesting heterogeneity of the cone. Magnetic modelling was conducted for three of those magnetisation highs. Each model implied the presence of concealed volcanic products overlain by pyroclastic rocks from the Fossa crater. The model for the Fossa crater area suggests a buried trachytic lava flow on the southern edge of the present crater. The magnetic model at Forgia Vecchia suggests that phreatic cones can be interpreted as resulting from a concealed eruptive centre, with thick latitic lavas that fill up Fossa Caldera. However, the distribution of lavas seems to be limited to a smaller area than was expected from drilling results. This can be explained partly by alteration of the lavas by intense hydrothermal activity, as seen at geothermal areas close to Porto Levante. The magnetic model at the north-eastern Fossa Cone implies that thick lavas accumulated as another eruption centre in the early stage of the activity of Fossa. Recent geoelectric surveys showed high-resistivity zones in the areas of the last two magnetic models.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.5
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• pp.578-588
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• 2008

The objective of this study was to evaluate associations of dietary sodium (Na) intake with salt-related dietary behaviors of 218 university students (95 men; 123 women) living in Gyeonggi area. Dish frequency questionnaire (DFQ) was used to identify salt-related dietary behaviors and to determine Na intakes. In men, systolic & diastolic blood pressures, Na intakes and DFQ-15 scores were significantly higher than in women. High-salt intake group (HS), classified by DFQ-15, had higher scores of high-salt dietary attitude and more Na intakes than low-salt intake group (LS). HS took protein foods and had balanced diets less frequently than LS (p<0.05). HS had fried dishes & fatty meats, and added salt to dishes more frequently (p<0.05). HS and LS had differences in preference of soy-boiled and Chinese or Japanese foods, in intake frequency of bean-paste soup, in use of soy sauce with fried food or raw fish, and in salt addition to dishes at the table (p<0.05). HS, classified by Na intakes, had high-salt dietary attitudes such as preference of seasoned rice & soy-boiled foods and habitual addition of soy sauce or salt to dishes at the table. The subjects using food labels when purchasing had better salt-related attitudes & behaviors, and lower DFQ-15 scores & Na intakes than the non-users (p<0.01). Self-assessed HS (SHS) had worse salt-related attitudes and behaviors (p<0.05). Male self-assessed LS (SLS) had higher Na intakes, which indicated that self-assessment of salt preference did not actually reflect Na intake. In summary, male university students belonged to a high-risk group of salt intakes, and HS preferred soy-boiled foods or fatty dishes, frequently added salt to dishes and rarely had balanced diets. These results suggest that nutrition education programs for university students should include fundamental dietetics and a balanced diet, in addition to a low-Na diet.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.1
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• pp.175-182
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• 2001

The main focus of this study was set to help college students in Kangwon province to improve and correct dietary habits and to maintain healthy life. The nutritional status and food preference of college students were examined from May to July, 1999. The collection of the research data has been made on the basis of questionnaries for 184 college students residing in Kangwon province. Statistical analysis of the data was performed using SAS package program for descriptive frequency and statistical significance. The meal skipping ratio of the subjects were 2% and for the reasons of meal skipping 45% responded "lack of time". As for main dishes, cooked rice turned out to be the most preferred by the subjects and the second and third favored by female students were bread and noodle respectively. Most preferred side-dishes were meat soup, kimchi, laver Kui,squid Bockeum, fried squid, beef Chon, squid Chorim, soy Namul, Dubuk Changachi and squid Muchim. Less preferred side-dishes include radish soup, white kimchi, mugwort fry, liver Bockeum, liver sheon and egg plant Kui. No one-plate food was disliked by the subjects. Male liked Manndukuk and female liked cuttle fish rice. The intakes of nutrient except for energy, iron and calcium for female students were the same or above the Recommended Dietary Allowances (RDA) for Koreans.

• Journal of agricultural medicine and community health
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• v.34 no.1
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• pp.76-86
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• 2009

Objectives: This study was conducted to find out the frequency of urinary incontinence among the rural elderly people and its related factors. Methods: Informations have been obtained through interviews from the 464 rural residents of advanced age over 65 years on September 1st through November 30th, 2007, in Chungnam Province. Results: As for the rate of experiencing urinary incontinence, the group with the experience rate of 「every day」 were 9.5% and 「occasionally」 35.5%, with the total of 45.0%. The higher rates of urinary incontinence were in the elderly women(58.5%) than in the elderly men (29.8%), in the more advanced in age, in the higher educated, and in the groups with higher monthly income. Based on life styles, the rate of experiencing urinary incontinence was significantly higher in smoking groups and non-drinking groups. Based on subjective senses of health, it was more highly associated with the groups who reported that they were not healthy, that they concerned themselves about health, that they had physical disability, that they had forgetfulness, and they needed assistance in terms of activity of daily living(ADL) and instrumental activity of daily living(IADL) than their respective counterparts. By the result of multiple logistic regression, sex, age, smoking status, anxiety, physical disability, amnesia, and IADL was indicated the affecting factors to the prevalence of urinary incontinence. Conclusions: The above results reveal that the rate of urinary incontinence was higher in the elderly women than the elderly men, and in more advanced age. Moreover, its rate increases in the groups with undesirable life styles or lower senses of subjective and physical health conditions. It is highly suggested that efforts to manage urinary incontinence of the elderly need to be narrowed to the more advanced, especially those with lower standards of health conditions.

• Journal of the Korean Geographical Society
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• v.42 no.4
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• pp.540-559
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• 2007

The purpose of this paper is to analyse the locations and to interpret the landscapes of the local towns in Joseon Dynasty from Feng-shui's point of view. As a result of analysing the locations of towns in Gyeongsang Province, the towns which have typical Feng-shui landscapes make up to 58% of the total. Historically, the local towns that were established in the early period of the Joseon Dynasty didn't reveal Feng-shui's landscape, but those that were established in the late period of the Joseon Dynasty revealed the Feng-shui's landscape clearly. In this article, I classify the local towns of the Gyeongsang Province into 3 types: 1. Non Feng-shui type These towns are located near the seashore. The main reason that these towns were located at the seashore was defense against an enemy. 2. Semi Feng-shui type. These towns don't have natural location but have a man-made landscape, based on the principles of Feng-shui. 3. Typical Feng-shui type. These towns were typically administrational towns which were located at the center of a local region.