• 상하수도학회지
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• 제11권4호
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• pp.99-109
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• 1997

To estimate the nutrients delivery characteristics of Chogang stream to Keum River, sediment and soil characteristics were analyzed in the stream and in the stream bank. Along the stream, soil samples from river sediment were collected and tested monthly for phosphorus and nitrogen concentrations. Nitrogen concentration in the sediment is much lower than that of soil in the river bank especially in summer presumably due to the high desorption characteristics of nitrogen by the increasing rainfall energy during summer. Instead, the concentrations of phosphorus were similar for the sediment and the soil in the river bank due to the strong adsorption characteristics of phosphorus. Batch tests were performed to evaluate the desorption potential of the sediments. Universal Soil Loss Equation (USLE) was applied to quantify soil erosion in each watershed due to rainfall. It was estimated that approximately 25% of total phosphorus by mass basis could be released from the sediment if the water was disturbed vigorously. The mass load of nitrogen and phosphorus into the Chogang Stream from the watershed were evaluated from the USLE and release ratio of phosphorus.

• Nutrition Research and Practice
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• 제15권4호
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• pp.528-540
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• 2021

BACKGROUND/OBJECTIVES: In a healthy person, from 35 years of age, there is an annual loss of muscle mass at the rate of 1-2% and is associated with a decline in the quality of life. This study aimed to identify the particular dietary patterns associated with the risk of lower lean muscle mass in Korean postmenopausal women. SUBJECTS/METHODS: The Korea National Health and Nutrition Examination Survey (KNHANES) is a population-based, continuous cross-sectional annual survey. The participants of the KNHANES IV (2008-2009) and V (2010-2011) were considered for this study. The study sample consisted of 1548 postmenopausal women, aged 45-86 years. Lower lean muscle mass was defined as having appendicular skeletal muscle mass corrected for body weight less than 1 standard deviation of the young reference group aged 20 to 39 years in KNHANES IV and V. To identify the dietary pattern using factor analysis, 24-h recall data was used. RESULTS: The prevalence of lower lean muscle mass was 31.3% in this study population. Four dietary patterns were identified by factor analysis; 'Diverse', 'Western', 'Traditional', and 'Snacks and beverages'. The 'Western' pattern, highest factor loadings for flour and bread, potatoes, red meat, processed meat, eggs, and cheese, was significantly associated with a high (60%) risk of lower lean muscle mass (odds ratio [95% confidence interval] = 1.60 [1.07-2.39], P for trend = 0.01) after adjustments for potential covariates. The other 3 dietary patterns were not associated with lower lean muscle mass. CONCLUSIONS: The study findings suggest that the 'Western' dietary pattern that includes flour and bread, potatoes, red meat, processed meat, eggs, and cheese, may be associated with a higher risk of lower lean muscle mass in Korean postmenopausal women.

• 대한기계학회논문집
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• 제15권6호
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• pp.2171-2180
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• 1991

본 연구에서는 구심터어빈의 설계시 많이 사용되고 있는 NASA의 안내깃 및 회 전익 손실모델들을 이용하여 PR과 K를 실험에 의존하지 않고 구하는 방법을 제시하고 자 한다. 그리고 이 방법을 가변 안내깃이 존재하거나 없는 가상의 구심터빈에 대하 여 탈설계 성능해석을 하여, 본 방법이 기존에 알려진 실험 현상과 유사한 경향을 보 이는지를 알아보기로 한다. 또한 안내깃이 있는 경우에 대하여 기존의 알려진 탈설 계 성능 예측용 프로그램과의 비교를 통하여 본 연구의 해석방법을 간접적으로 검증하 기로 한다.

• Journal of Periodontal and Implant Science
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• 제49권3호
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• pp.158-170
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• 2019

Purpose: This study investigated the association between health status and tooth loss based on data from the National Health Insurance Service-Health Examinee Cohort in 2002-2015. Methods: Multivariate Cox proportional hazards regression analyses were applied to a longitudinal retrospective database, which was updated and newly released in 2018, to assess the association between health status and tooth loss while adjusting for potential confounders among sociodemographic and economic factors (sex, age, household income, insurance, and presence of disability), general and oral health status (body mass index [BMI], smoking and drinking status, periodic dental visits and scaling, and brushing before sleep), and comorbid disease (hypertension, diabetes mellitus [DM], and Charlson comorbidity index [CCI]). Results: Among 514,866 participants from a South Korean population, 234,247 (45.5%) participants satisfying the inclusion criteria were analyzed. In the adjusted multivariate analysis, sex, age, household income, insurance, presence of disability, BMI, smoking and drinking status, periodic scaling, tooth brushing before sleep, DM, and CCI showed statistically significant associations with the loss of at least 1 tooth. The risk of experiencing a loss of ${\geq}4$ teeth was associated with an increase in age (in those 50-59 years of age: hazard ratio [HR], 1.98; 95% confidence interval [CI], 1.93-2.03; in those 60-69 years of age: HR, 2.93; 95% CI, 2.85-3.02; and in those 70-79 years of age: HR, 2.93; 95%, CI 2.81-3.05), smoking (HR, 1.69; 95% CI, 1.65-1.73), and DM (HR, 1.43; 95% CI, 1.38-1.48). Conclusions: The results of this study showed that the risk of experiencing tooth loss was related to multiple determinants. DM and smoking were especially significantly associated with tooth loss.

• Nutrition Research and Practice
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• 제17권2호
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• pp.218-227
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• 2023

BACKGROUND/OBJECTIVES: Malnutrition during hospitalization is linked to increased morbidity and mortality, but there are insufficient studies observing clinical factors contributing to weight loss during hospitalization in Indonesia. This study was therefore undertaken to determine the rate of weight loss during hospitalization and the contributing factors. SUBJECTS/METHODS: This was a prospective study involving hospitalized adult patients aged 18-59 yrs, conducted between July and September 2019. Body weight measurement was taken at the time of admission and on the last day of hospitalization. The factors studied were malnutrition at admission (body mass index < 18.5 kg/m²), immobilization, depression (Beck Depression Inventory-II Indonesia), polypharmacy, inflammatory status (neutrophil-lymphocytes ratio; NLR), comorbidity status (Charlson Comorbidity Index; CCI), and length of stay. RESULTS: Totally, 55 patients were included in the final analysis, with a median age of 39 (18-59 yrs) yrs. Of these, 27% had malnutrition at admission, 31% had a CCI score > 2, and 26% had an NLR value of ≥ 9. In all, 62% presented with gastrointestinal symptoms, and depression was documented in one-third of the subjects at admission. Overall, we recorded a mean weight loss of 0.41 kg (P = 0.038) during hospitalization, with significant weight loss observed among patients hospitalized for 7 days or more (P = 0.009). The bivariate analysis revealed that inflammatory status (P = 0.016) was associated with in-hospital weight loss, while the multivariate analysis determined that the contributing factors were length of stay (P < 0.001) and depression (P = 0.019). CONCLUSIONS: We found that inflammatory status of the patient might influence the incidence of weight loss during hospitalization, while depression and length of stay were independent predictors of weight loss during hospitalization.

• Journal of Positioning, Navigation, and Timing
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• 제7권2호
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• pp.105-112
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• 2018

This paper manufactured an active GPS antenna for ground vehicles and presented a method to verify the performances of the antenna and component technology of the low noise amplifier (LNA) board manufacturing. The manufactured GPS antenna is an active antenna where microstrip patch and LNA board were combined. The main performances were standing wave ratio, antenna gain, and axial ratio, and all satisfied the target specifications. The proposed component technology can be utilized as a basis data in which the performance of LNA board can be compensated in the mass production process inspection, and employed as a method to verify whether antennas are properly working in environmental tests.

• 설비공학논문집
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• 제27권7호
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• pp.362-368
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• 2015

This paper presents a numerical study on the performance of a vapor compression cycle equipped with an ejector as an expansion device to improve the COP by reducing the expansion loss and compressor work. The simulation is carried out using a model based on the conservation of mass, energy and momentum in the ejector. From the results of the simulation, the vapor compression cycle equipped with an ejector showed a maximum COP improvement of 14.0% when using R134a refrigerant and 16.8% when using R1234yf. In addition, the performance of the system with an ejector represents the increased performance as the temperature difference between condensing and evaporating increased.

• Preventive Nutrition and Food Science
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• 제22권1호
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• pp.45-49
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• 2017

The anti-obesity effects of yeast hydrolysate (YH) supplementation (1.0 g/d) have already been demonstrated. We investigated whether a low dose of YH (0.5 g/d, YH-500) also has the anti-obesity effects. Thirty obese women were randomly assigned to the control or YH-500 groups. After 8 weeks, weight and body mass index were significantly reduced by the YH treatment (0.5 g/d) (P<0.05). The YH-500 group lost a significant amount of body fat after the 8-week treatment: fat mass 25.9 kg (baseline) versus 23.8 kg (8th week), P<0.01; fat mass ratio 38.8% (baseline) versus 36.5% (8th week), P<0.05. The YH-500 group showed a significant reduction in calorie intake during the 8-week treatment (P<0.001). The control group wanted to eat much more food (P<0.05) and sometimes thought about eating more often compared with the YH-500 group (P<0.05). Whereas the control group showed a slightly increased sweet preference, the YH-500 group showed a significant reduction in sweet preference (P<0.05). In conclusion, low dose YH supplementation (0.5 g/d) may induce a reductions in weight and body fat in obese women via the reduction of calorie intake.

• Journal of Medicine and Life Science
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• 제19권2호
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• pp.39-45
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• 2022

This study was undertaken to assess the potential of body mass index (BMI) as a risk factor for massive hemorrhage (MH) after cesarean section (CS) in patients with placenta previa. We retrospectively reviewed the medical records of patients who underwent CS for placenta previa between January 2010 and December 2018. MH was defined as an estimated blood loss ≥2,000 mL during surgery. Clinical characteristics, including BMI, were compared between the groups with and without MH. Subsequently, multivariable logistic regression analysis was conducted to identify the independent risk factors for MH. A total of 189 patients were included in this study. MH was observed in 28 patients (14.8%). According to the multivariable logistic regression analysis results, the risk factors independently associated with MH were BMI at delivery (adjusted odds ratio [aOR], 1.19; 95% confidence interval [CI], 1.04-1.35; P=0.012), placenta accrete (aOR, 24.55; 95% CI, 2.75-219.02; P=0.004), and total previa degree (aOR, 9.86; 95% CI, 2.71-35.96; P=0.001). The study findings showed that maternal obesity, namely a higher BMI at delivery, was an independent risk factor for MH after CS in patients with placenta previa. Close attention should be paid to the potential risk of hemorrhage associated with maternal obesity as well as the well-known risk factors of placenta accreta and total previa degree.

• Design & Manufacturing
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• 제13권2호
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• pp.37-43
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• 2019

This study conducted a research as to condensation heat transfer friction loss headby using three types of flat micro multi-channel tubes with different processing of micro-fin and number of channels inside the pipes and different sizes of appearances. In addition, identical studies were conducted by using smoothing circular tubes with 5mm external diameter to study heat enhancement factor and pressure drop penalty factor. 1) The friction head loss showed an increase as the vapor quality and mass flux increased. In case of saturation temperature, it shows an increase as it gets lower. These factors are the reason occurring as the lower the saturation temperature is, the higher the density of refrigerant vapor gets. The influence of heat flux is similar as the dryness is low, but as it gets higher, it lowers in heat flux, and as the high temperature of high heat flux, it is a factor that occurs as the density gets lower. 2) RMS error of the in case of friction head loss, it showed to be predicted as 0.45~0.67 by Chisholm, Friedel, Lockhart and Martinelli. 3) As forfriction head loss penalty factor, the smaller the aspect ratio is, the larger the penalty factor gets, and as for the effect of micro-fin, the penalty factor increased because it decreases to the gas fluid the way groove for the refrigerant's flow.