• The Transactions of the Korean Institute of Power Electronics
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• v.10 no.4
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• pp.380-387
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• 2005

We report the performance of an open-frame type low-voltage high-current DC-DC converter module developed using an active clamp forward converter circuit and single ended rectifier. The converter module is designed with the specifications of an 3.3V output voltage, 30A output current, 100W output power and 36-75V input voltage. The synchronous rectifier is used to reduce the conduction loss at high current level and constant current control using precision PCB resistance is adapted to enhance the over current protection function in the system configuration. A prototype converter module is successfully implemented within 8mm height and quarter brick size (58x37mm) and recorded an $95W/in^3$ power density, 90.6$\%$ efficiency and 0.07$\%$ voltage regulation for the entire Input voltage range, thereby demonstrating its application potentials to future telecommunication electronics.

• Korean Journal of Community Nutrition
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• v.17 no.1
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• pp.101-108
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• 2012

The purpose of this survey is to investigate the nutritional status and dietary intake of gastrectomized cancer patients in Asan Medical Center. The subjects were 98 patients, who underwent a gastrectomy due to gastric cancer and were admitted to the General Surgery Department during March 2007 to December 2007. We examined general characteristics (sex, age, clinicopathological stage, type of operation), anthropometric data (height, weight change), biochemical data (red blood cell RBC, hemoglobin HGB, hematocrit HCT, mean corpuscular volume MCV, total lymphocyte count TLC, albumin, total cholesterol), dietary intake and dietary intake related symptoms. Weight loss of gastrectomized patients was $9.0{\pm}4.3$% from preillness weight to visiting out-patient department (OPD) weight. Biochemical data (RBC, HGB, HCT, MCV, TLC, albumin, total cholesterol) significantly deteriorated after gastrectomy. However, outpatient visits were all restored to the normal range. Postoperative energy intake was $785.0{\pm}164.2$ kcal, which corresponds to $41.6{\pm}9.6$% of daily energy requirement. The cause of poor oral intake is mostly fear, abdominal pain and abdominal discomfort. Therefore, to control pre-or post-operative weight change in the future requires, focusing on the body weight to maintain a normal or usual nutrition by interventions and increased caloric intake during hospitalization for the development of nutrient-dense meals. In addition, as the main reason of the lack of intake of meals after the gastrectomy was fear, the patients should be actively encouraged to consider the importance of eating proper meals.

• The Korean Journal of Physiology and Pharmacology
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• v.19 no.1
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• pp.9-14
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• 2015

We investigated the sweating response during passive heating (partial submersion up to the umbilical line in $42{\pm}0.5^{\circ}C$ water, 30 min) after summer and winter seasonal acclimatization (SA). Testing was performed in July during the summer, 2011 [summer-SA; temp, $25.6{\pm}1.8^{\circ}C;$ relative humidity (RH), $82.1{\pm}8.2%$] and in January during the winter, 2012 (winter-SA; temp, $-2.7{\pm}2.9^{\circ};$ RH, $65.0{\pm}13.1%$) in Cheonan ($126^{\circ}52^{\prime}N$, 33.38'E), Republic of Korea. All experiments were carried out in an automated climatic chamber (temp, $25.0{\pm}0.5^{\circ}C$: RH, $60.0{\pm}3.0%$). Fifteen healthy men (age, $23.4{\pm}2.5$ years; height, $175.0{\pm}5.9cm;$ weight, $65.3{\pm}6.1kg$) participated in the study. Local sweat onset time was delayed during winter-SA compared to that after summer-SA (p<0.001). Local sweat volume, whole body sweat volume, and evaporative loss volume decreased significantly after winter-SA compared to those after summer-SA (p<0.001). Changes in basal metabolic rate increased significantly after winter-SA (p<0.001), and tympanic temperature and mean body temperature were significantly lower after summer-SA (p<0.05). In conclusion, central sudomotor acitivity becomes sensitive to summer-SA and blunt to winter-SA in Rebubic of Korea. These results suggest that the body adjusts its temperature by economically controlling the sweating rate but does not lower the thermal dissipation rate through a more effective evaporation scheme after summer-SA than that after winter-SA.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.2
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• pp.530-535
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• 2005

A Korean traditional herbal formular, Taeumbiman-tang(TBT), was based on Taeumjowi-tang, currently the most widely used herbal formula compound, and which is known to be safe and have a positive effect on adult obesity. TBT was given to obese children for thirty days, and was found to be clinically safe and effective. The subjects were children who had been admitted into the hospital to be treated for obesity, that had more than 20% relative body weight. Originally there were 19 subjects, but 5 dropped out of the experiment. There were 5 girls and 9 boys, whose average ages were $11.00\;{\pm}\;2.60$ years, average weight was $54.01\;{\pm}\;18.59\;kg$. As a pretest, all of the volunteers were examined for height, weight, blood pressure, pulse rate, EKG, and chest radiography. The subjects underwent interview, body measurement tests, blood tests, and safety tests under 8 hour fasting state. After 15 days of TBT intake, the safety tests and the interview were conducted. The interview, body measurement tests, blood tests, and safety tests were conducted again after the 30 day trial was completed. The short term effects of TBT on obese children is weight loss. It did not cause any significant changes in the subject's livers, hearts, and kidneys, and clinically dangerous side effects or withdrawal symptoms were not observed.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.3
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• pp.233-243
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• 2014

The difference of mooring tension by type of buoy was investigated in the circulating water channel and the wave tank for deducting the most stable buoy from the current and the wave condition. 5 types of buoy made up of short cylinder laid vertically (CL-V), short cylinder laid horizontally (CL-H), capsule (CS), sphere (SP) and long cylinder (CL-L) were used for experiments. A mooring line and a weight were connected with each buoy. A tensile gauge was installed between a mooring line and a weight. All buoy's mooring tension was measured at the same time for the wave test with periods of 1.5~3.0 sec and wave heights of 0.1~0.3 m, and the current test with flow speeds of 0.2~1.0 m/sec. As a result, the order of tension value in the wave test was CL-H > CL-V > SP > CS > CL-L. In the current test CL-V and CL-H were recorded in the largest tension value, whereas SP has the smallest tension value. So it seems that SP buoy is the most effective in the location affected by fast current. CS is predicted to be suitable for a location that influence of wave is important more than that of current if practical use in the field is considered. And it was found that the difference of mooring tension among buoys in wave is related to the product of the cross sectional area and the drag coefficient for the buoy's bottom side in high wave height. The factor for the current condition was not found. But it was supposed to be related to complex factors like a dimension and a shape by buoy's posture to flow.

• The Korean Journal of Food And Nutrition
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• v.20 no.3
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• pp.325-333
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• 2007

This study was conducted to investigate the weight concerns of female university students living in Jeonju, as well as their control on behavior. Self-administered questionnaires were collected from 285 students. Statistical data analysis was completed using the SPSS v. 11.0 program. The results are summarized as follows: The average weight, height, and BMI of the subjects were 21.43 kg, 161.93 cm, and 19.8, respectively. With regard to body image, most were dissatisfied with their figures, especially the hips and thighs. About 42% of the students estimated their figures as 'slightly fat', while 5.4% stated 'very fat', even though their BMI classified as 'normal'. Four percent of the underweight students described themselves as being 'fatty'. Approximately 93% of the students had strongly pursued weight control, and 45.3% reported wanting to lose about $2{\sim}5$ kg. Almost 73% of the respondents had weight loss experience. The primary reason for weight control was to improve self-confidence. Only 19.6% had succeeded in losing weight, while nearly 48% had stopped dieting. To reduce weight, about two thirds of the students ate less(e.g. no snacks, no sweets). Fifty percent tried to reduce weight by more physical activity(e.g. sports). Television(50.9%), friends(48.4%), and newspapers/magazines(40.4%) were essential sources of pertinent information. In conclusion, the results show that female students in Jeonju have a great interest in weight reduction. Thus, the majority are willing to try several methods for weight reduction, which however, are not promising and not based on a lasting nutritional change. Therefore, it's necessary to increase cooperation among those concerned(e.g. dietitians, teachers, parents, media) and to develop weight-control programs that take into consideration lifestyle and daily habits, as well as combine physical activity, nutrition, and behavioral and personality training.

• Journal of Korean Medical Science
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• v.33 no.50
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• pp.320.1-320.8
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• 2018

Background: Muscle mass and muscle function are related to depressed mood in studies of adults. Like adults, Korean students are highly likely to suffer from decreased muscle mass due to social conditions. In this study, we evaluated the muscle mass status of Korean adolescents and assess the effect of muscle on depressive mood. Methods: A total of 1,233 adolescent boys and girls participants from the Korea National Health and Nutrition Examination Survey were enrolled in our study. Participants underwent dual-energy X-ray absorptiometry for assessment of appendicular muscle mass and completed questionnaires regarding depressed mood, stress, suicidal ideations, and attempts. Results: There was no difference in depressive mood according to muscle mass among boys (P = 0.634); girls with decreased muscle mass had a greater tendency for depressed mood compared to girls with optimal muscle mass (P = 0.023). After adjusting for age, waist circumference-to-height ratio, smoking status, alcohol consumption, frequency of physical activity, self-reported obesity, weight-loss efforts, and monthly household income, girls with low muscle mass (LMM) were 2.60 times more at risk of developing depression than girls with normal muscle mass (95% confidence interval [CI], 1.05-6.49; P = 0.040). This trend was similar for girls with LMM with obesity (95% CI, 1.00-11.97; P = 0.049). Conclusion: Adolescent girls who have insufficient muscle mass are more likely to report depressed mood than girls who have ideal muscle mass. Interventions for maintaining proper muscle mass are required.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.4
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• pp.246-254
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• 2015

This study explored the effect of rainfall pattern and soil characteristics on water management in rice paddy fields, using a soil water balance model, BUDGET. In two sites with different soil textural group, coarse loamy soil (Gangseo series) and fine soil (Hwadong series), respectively, we have monitored daily decrease of water depth, percolation rate, and groundwater table. The observed evapotranspiration (ET) was obtained from differences between water depth decrease and percolation rate. The root mean square difference values between observed and BUDGET-estimated ET ranged between 10% and 20% of the average observed ET. This is comparable to the measurement uncertainty, suggesting that the BUDGET model can provide reliable ET estimation for rice fields. In BUDGET model of this study, irrigation requirement was determined as minimum water need for maintaining water-saturated soil surface, assuming 100 mm of bund height and no lateral loss of water. The model results showed different water balance and irrigation requirement with the different soil profile and indicated that minimum percolation rate by plow pan could determine the irrigation requirement of rice paddy field. For the condition of different rainfall distribution, the results presented different irrigation period and amounts, representing the importance of securing water for irrigation against different rainfall pattern.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.6
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• pp.644-652
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• 2017

Clover, a legume crop, is a landscape crop and green manure crop that can be sowing in spring. Clover serves various roles such as landscape composition, weeds suppressing, prevention of soil loss and nutrients on sloping, atmosphere purification, and supplying nitrogen in soil. Thus, in order to utilize this crop in agricultural land, we observed its effect on growth and carbon uptake in upland soil. The plant height of clover species increased with late harvesting time and was 46.0~55.0 cm at 90 days after seeding (DAS) and the longest in red clover. The dry matter increased at 85 DAS, after that, decreased slightly. The dry matter of white clover and red clover was $3.0Mg\;ha^{-1}$ and $3.1Mg\;ha^{-1}$, respectively, and crimson clover was $2.5Mg\;ha^{-1}$, significantly lower than other clover. Crops bloomed at 90 DAS were white clover and crimson clover, the period from sowing to flowering was 78 days for crimson clover and 85 days for white clover. The nitrogen content of the clover species was $12.0{\sim}29.3g\;kg^{-1}$, with the highest of $29.3g\;kg^{-1}$ for white clover. The carbon content of clover species was similar in all clover species, but carbon uptake was high in white clover and red clover, and lowest in crimson clover. The carbon uptake of the plant increased to 85 DAS and then decreased. Based on the clover growth and carbon uptake, white clover and red clover were promising when sown in spring.

• Clinical and Experimental Reproductive Medicine
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• v.48 no.3
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• pp.211-220
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• 2021

Objective: The present study aimed to investigate the possibility that curcumin (CMN) protects against methotrexate (MTX)-induced testicular damage by affecting the phospho-p38 (p-p38) mitogen-activated protein kinase (MAPK) and nuclear factor-kappa B (NF-κB) signaling pathways. Methods: Eighteen male Wistar albino rats were randomly divided into three groups. The control group was given an intragastric administration of dimethyl sulfoxide (DMSO) daily for 14 days, the MTX group was given a single intraperitoneal dose of MTX (20 mg/kg) on the 11th day, and the MTX+CMN group was given intragastric CMN (100 mg/kg/day, dissolved in DMSO) for 14 days and a single intraperitoneal dose of MTX (20 mg/kg) on the 11th day. At the end of the experiment, all animals were sacrificed and the testicular tissues were removed for morphometry, histology, and immunohistochemistry. Body and testicular weights were measured. Results: Body weights, seminiferous tubule diameter, and germinal epithelium height significantly decreased in the MTX group compared to the control group. Whereas, the number of histologically damaged seminiferous tubules and interstitial space width significantly increased in the MTX group. In addition, the number of p-p38 MAPK immunopositive cells and the immunoreactivity of NF-κB also increased in the MTX group compared to the control group. CMN improved loss of body weight, morphometric values, and histological damage due to MTX. CMN also reduced the number of p-p38 MAPK immunopositive cells and the NF-κB immunoreactivity. Conclusion: CMN may reduce MTX-induced testicular damage by suppressing the p38 MAPK and NF-κB signaling pathways.