• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.09a
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• pp.257-260
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• 2002

The main purpose of this research is to find suitable treatment methods of wastewater effluent for artificial recharge. For this purpose, we search the effluent quality of wastewater treatment plant and possibility of additional filtration process. Particles ranged 2 ~ 5 ${\mu}{\textrm}{m}$ and 15~20 ${\mu}{\textrm}{m}$ in "T" WWTP(Waste Water Treatment Plant) effluent were relatively dominant. In dual-media filtration system operation, head-loss development of column 1 was about two times faster than column 2, and head-loss development within 5 cm from surface was very important factor in operation, Conclusively, for the stable filtration and running time of 1.5~2 day, influent turbidity must keep 5 NTU or below, and filtration system must operated at 280 m/day or below. After filtration of WWTP effluent, water quality reached satisfactory level. This water has potential of agricultural reusing, flushing water in building, recharging water to river or stream at dry season and artificial recharge of ground water.und water.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.300-302
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• 2008

This paper will discuss the steps in building a wind farm and the modelling of AC power system for wind power generation. And take the JeJu island for an example, with its good wind power energy resource, the most important factor for a wind farm is a good power system interconnection to decrease the power loss including the transmission loss as less as possible. So in this paper, after the JEJU wind energy analysis, we will mainly discuss the development of the modelling on JEJU AC power system by using PSCAD. And also for using the real data of the wind power in the simulation, the modelling of the JeJu power system in 2011 will also be presented in this paper.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.1250-1251
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• 2008

In this study, the dielectric ceramics with low loss were investigated for high frequency application. All sample of the $Ba_5M_4O_{15}$ (M=Ta, Nb) ceramics were prepared by the conventional mixed oxide method and sintered at $1325{\sim}1575^{\circ}C$. The bulk density and dielectric constant of the $Ba_5Ta_4O_{15}$ ceramics were increased continuously with increasing of sintering temperature. The quality factor was increased in the sintering temperature of $1375{\sim}1475^{\circ}C$ but decreased at the temperature above 1475$^{\circ}C$. In the case of $Ba_5Nb_4O_{15}$ ceramics, the bulk density, dielectric constant and quality factor were increased with sintering temperature but decreased above temperature of 1400$^{\circ}C$. The dielectric constant, quality factor and temperature coefficient of the resonant frequency (TCRF) of the $Ba_5Ta_4O_{15}$ and $Ba_5Nb_4O_{15}$ ceramics, sintered at 1475$^{\circ}C$ and 1400$^{\circ}C$, were 25.15, 53105 GHz, -3.06 ppm/$^{\circ}C$ and 39.55, 28052 GHz, 5.7 ppm/$^{\circ}C$, respectively.

• Proceedings of the KIEE Conference
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• 2007.10c
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• pp.56-58
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• 2007

AC transport current losses is an important factor in the development of superconducting tapes and superconducting power applications. In this paper we compared measurement, calculation and Norris equation of AC transport current loss in BSCCO single and multi stacked wire. And present a distribution flux density and current density in the HTS single wire and multi stacked wire. The result of Measurement and calculation of Ac transport current loss show that the same. And show that HTS characteristic of inside HTS wire.

• Journal of the Korean Society of Physical Medicine
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• v.18 no.2
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• pp.13-21
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• 2023

PURPOSE: This study examined the specific clinical risk factors in middle-aged men with age-related loss of skeletal muscle mass (ALSMM). METHODS: The present research analyzed the data from a cross-sectional study of 1,564 community-dwelling participants aged between 40 to 49 years old. The participants were screened for ALSMM. The study examined various risk factors, including age, height, weight, body mass index, waist circumference, skeletal muscle mass index, smoking and drinking status, systolic and diastolic blood pressure, fasting glucose levels, and triglyceride and cholesterol levels. RESULTS: The risk factors of ALSMM were height, body mass index, waist circumference, skeletal muscle mass index, systolic blood pressure, diastolic blood pressure, drinking status, fasting glucose, and triglyceride levels (p < .05). The weight, triglyceride, and smoking status variables were non-significant (p > .05). CONCLUSION: The risk factors for ALSMM among community-dwelling adults were determined. These results are expected to contribute to the existing literature on ALSMM and provide potential risk factors associated with the development of ALSMM in middle-aged males.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.11a
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• pp.63-64
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• 2018

The construction industry is one of the most prolific disaster-prone industries, particularly those that suffer from falling disasters compared to other industries. The safety accident at the construction site leads to social problems caused by massive loss of life and property, so it needs to be extra careful. The reason why falls are the most frequent accidents of the types of construction accidents is due to the analysis of the risk factors of safety accidents and the development of various construction methods. Therefore, in this study, the accident case for the fallen victims of construction site was analyzed and the risk factor was selected. Based on the safety expert survey, an importance analysis was performed. In conclusion, this study analyzes various risk factors that affect the occurrence of falls, identifies the importance of each factor, and presents basic data for safety accident prevention activities.

• Spatial Information Research
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• v.14 no.4 s.39
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• pp.363-377
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• 2006

Mean annual soil loss was calculated and critical soil erosion areas were identified for the Congaree River Basin in South Carolina, USA using the Revised Universal Soil Loss Equation (RUSLE) model. In the RUSLE model, the mean annual soil loss (A) can be calculated by multiplying rainfall-runoff erosivity (R), soil erodibility (K), slope length and steepness (LS), crop-management (C), and support practice (P) factors. The critical soil erosion areas can be identified as the areas with soil loss amounts (A) greater than the soil loss tolerance (T) factor More than 10% of the total area was identified as a critical soil erosion area. Among seven subwatersheds within the Congaree River Basin, the urban areas of the Congaree Creek and the Gills Creek subwatersheds as well as the agricultural area of the Cedar Creek subwatershed appeared to be exposed to the risk of severe soil loss. As a prototype model for examining future effect of human and/or nature-induced changes on soil erosion, the RUSLE model customized for the area was embedded into ESRI ArcGIS ArcMap 9.0 using Visual Basic for Applications. Using the embedded model, users can modify C, LS, and P-factor values for each subwatershed by changing conditions such as land cover, canopy type, ground cover type, slope, type of agriculture, and agricultural practice types. The result mean annual soil loss and critical soil erosion areas can be compared to the ones with existing conditions and used for further soil loss management for the area.

• Journal of Periodontal and Implant Science
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• v.50 no.5
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• pp.303-312
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• 2020

Purpose: The purpose of this study was to evaluate severe periodontitis with tooth loss as a modifiable risk factor for Alzheimer dementia (AD), vascular dementia (VaD), and mixed dementia (MD) using the National Health Insurance Service-National Health Screening Retrospective Cohort database with long-term follow-up over 14 years. Methods: Multivariate Cox hazards regression analysis was applied to a longitudinal retrospective database, which was updated in 2018, to evaluate the association between severe periodontitis with few remaining teeth and dementia after adjusting for potential risk factors, including sociodemographic factors and comorbid diseases. Results: Among 514,866 individuals in South Korea, 237,940 (46.2%) participants satisfying the inclusion criteria were selected. A total of 10,115 age- and sex-matched participants with severe periodontitis and 10,115 periodontally healthy participants were randomly selected and evenly assigned. The results showed that the risks of AD (hazard ratio [HR], 1.08), VaD (HR, 1.24), and MD (HR, 1.16) were significantly higher in patients with severe periodontitis with 1-9 remaining teeth after adjustment for sociodemographic factors, anthropomorphic measurements, lifestyle factors, and comorbidities. Conclusions: Severe periodontitis with few remaining teeth (1-9) may be considered a modifiable risk factor for the development of AD, VaD, and MD in Korean adults.

• Journal of Korean Academy of Nursing
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• v.29 no.6
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• pp.1294-1303
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• 1999

The purpose of this study was to develop a tool to assess the powerlessness and to measure the powerlessness of elderly. From the result of pre-test, twenty seven items were finally selected to survey the elderly's powerlessness. The questionnaires on the elderly's powerlessness were drafted so that such tool may be evaluated in accordance with the four point Likert Scale. The number of subjects is 1,150 with ages of 60 years or more and who live in a large city, a small and middle-sized city and a rural area. The subjects of the test and retest were 85 elderlies. Collected data were analyzed by utilizing SAS program with Cronbach's $\alpha$ and Pearson's correlation, factor analysis method and known group techniques, descriptive statics, t-test and ANOVA. The results from this study were summarized below:1. When the factor analysis method was applied for validity, the tool for powerlessness of elderly was separated into 5 factors: loss of self-confidence to deal with physical, emotional, social aspects of life; expulsion by others from meaningful human relate; perception that life is meaningless and time passes quickly; falling behind young people; being rejected by other people, having no influence on others. An application of the known group technique showed a significant difference with the result of the degree of elderly's powerlessness tools developed by the two groups, with illness and without. 2. In testing reliability, it was found that coefficient of test-retest was .9435(P<.0001) when the test-retest method was used as a test of stability, and that the alpha coefficient of internal consistency was .9141 over all items within the tool of elderly's powerlessness 3. In powerlessness of elderly, total mean is 2.8493. And in factor of powerlessness, the highest factor is falling behind young people (M=3.1713), the lowest factor is loss of self- confidence to deal with physical, emotional, social aspects of life(M=2.6080). 4. The results from the test for the degree of powerlessness, according to the subject's demographic variables, showed that there were significant differences between age, sex, marital status, educational level, religion, possession of house, job, monthly pocket money, health status, illness and a place of residence.

• Toxicological Research
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• v.9 no.1
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• pp.61-67
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• 1993

LBD-005, a newly developed recombinant granulocyte-macrophage colony-stimulating factor, was at dose levels of 0, 20, 80 and 320ng/kg/day administered subcutaneously to pregnat New Zealand White rabbits during the organogenetic period. The dams were subjected to caesarean section on day 28 of pregnancy. Effects of test substance on dams and embryonal development of fetuses were examined. No treatment-related changes in clinical signs and necropsy findings of dams were observed in all groups. At 80 and 320 ng/kg, a significant decrease in food consumption followed by a loss in body weight was found.