• Composites Research
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• v.27 no.5
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• pp.190-195
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• 2014

This paper predicts the complex permittivity of MWNT added epoxy depending on agglomeration by numerical analysis. 1wt% MWNT added epoxy specimen is prepared using 3-roll-mill method and its complex permittivity is measured in X-band (8.2~12.4 GHz) using freespace measurement system. The analytic model is comprised of cube epoxy and perfect sphere agglomeration. The complex permittivity of the agglomeration model is predicted by complex permittivity mixing rule using the measured complex permittivity of epoxy and 1 wt% MWNT added epoxy. Commercial electromagnetic analysis software, CST, is used to obtain S-parameter of the analytic model and MATLAB code is used to calculate complex permittivity from the S-parameter. It is confirmed that the complex permittivity increases when the agglomeration size decreases.

• Journal of Ecology and Environment
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• v.43 no.4
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• pp.341-351
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• 2019

Background: Standing biomass, litter production, rate of litter decomposition, amount of litter on forest floor, and amount of soil organic carbon distribution were investigated from March 2016 to November 2018 in order to evaluate the ecosystem value through organic carbon distribution in the Pinus densiflora forest at Namsan, Seoul Metropolitan City. Results: The amount of organic carbon in the Pinus densiflora forest was 261.09 ton C ha^-1 during the research period, and fixed organic carbon in plant through net photosynthesis was 3.2 ton C ha^-1 year^-1. The organic carbon in plant was 62.77 ton C ha^-1 (24.04%), in litter on the forest floor was 3.65 ton C ha^-1 (1.40%), and in soil was 194.67 ton C ha^-1 (74.56%). The value of plant, litter on forest floor, and soil organic carbon distribution were each 6,277,000 won ha^-1, 365, 000 won ha^-1, and 19,467,000 won ha^-1. The value per ton of fixed organic carbon in plant through net photosynthesis was 320,000 won ha^-1 year^-1 and the value of ecosystem services stored in carbon in the Namsan forest ecosystem was about 26.1 million won ha^-1 for 3 years. Conclusions: The results of this study suggest that the pine forests of Namsan rapidly decompose leaves due to the high atmospheric temperature and accumulate a large amount of organic carbon in the soil to provide climate control regulatory service function.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.2
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• pp.235-244
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• 2014

This paper describes the subarray channel configuration and calibration method for airborne AESA radar antenna. AESA radar demonstrator was designed and implemented for the digital beam-forming performance test of the 12 channel subarray structure. Magnitude and phase difference can be exist between the manufactured subarray channel. In this paper, calibration method for the subarray difference error was suggested. We measured digital monopulse slope in the subarray channel and verified the channel calibration effect. To verify the subarray channel operation, digital monopulse channel was compared with analog monopulse channel performance. AESA radar demonstrator was tested in the ground far field test range. Emulated single target was generated to test the detection and tracking performance of the demonstrator with the same waveform and search pattern. We verified that the detection and tracking performance of the 12 subarray digital monopulse channel was similar with the conventional analog monopulse channel. Also, ABF(Adaptive Beam-Forming) function for the sidelobe jammer was tested and effective operation was verified.

• Journal of Oriental Medical Thermology
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• v.3 no.1
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• pp.6-14
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• 2004

Purpose: We intended to research the relations between abdominal temperature and primary dysmenorrhea severity. Methods: We selected the 95 primary dysmenorrhea patients by means of screening test (first screening test-inquiry, second screening test-clinical test, additionally Waist-to-Hip ratio (WHR) by Inbody 2.0). We measured 4 points abdominal temperature (Chon-jung(CV17), Chung-wan(CV12), Kwan-won(CV4), Chung-guk(CV3)) by DITI (DOREX Inc., USA). And then we checked the difference of temperature $({\Delta}T)$ between CV17 and CV4 / CV17 and CV3 / CV12 and CV4 / CV12 and CV3. After that, we compared ${\Delta}T$ with primary dysmenorrhea severity evaluated by multidimensional scales (verbal rating scale modified from the one devised by Bibe roglu & Berhrman(VRS; B&B), multidimensional verbal rating scale by Andersch & Milsom(MVRS)). In dysmenorrhea severity, we standardized scale score and 3-group-severity by score (mild, moderate, severe). For statistics, we used Pearson correlations and Spearman's rho correlations, SPSS 11.0 for windows. Results: In case of MVRS, MVRS score and 3-group-severity were not correlated to ${\Delta}T$. In case of VRS; B&B, VRS; B&B score was correlated to ${\Delta}T$ (CV12 and CV4 / CV12 and CV3) and 3-group-severity was correlated to ${\Delta}T$ (CV12 and CV3). Statistically they showed significant result (p<0.05). So we can consider that ${\Delta}T$ (CV12 and CV3) and the primary dysmenorrhea severity by VRS; B&B are most correlated. Conclusion: The primary dysmenorrhea patients showed that severity by VRS; B&B was connected with ${\Delta}T$ (CV12 and CV3). So we can consider DITI as primary dysmenorrhea evaluation instrument and must further research measurement points for the exact primary dysmenorrhea evaluation by DITI.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.10
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• pp.1258-1264
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• 2017

The effects of two cooking methods (grilling and boiling) on fat content, fatty acid composition, vitamin A, and vitamin E levels of chicken (breast, wing, thigh, and leg) were investigated. Cooking loss was in the range of 19.09~41.17%, and grilled chicken showed higher cooking loss than boiled chicken in all parts except the thigh. All treatments enhanced fat content except boiled chicken breast. Fatty acid contents of chicken significantly increased or decreased after heat treatments (P<0.05). Grilled wing showed the highest levels of saturated (SFA) and unsaturated fatty acids (UFA), and the highest UFA/SFA ratio was detected in boiled thigh. The highest content of trans fatty acids was detected in boiled wing (137.67 mg/100 g), although no significant difference with grilled wing (P>0.05), and trans fatty acids in breast was not detected. The content of vitamin A tended to decrease with heating in all chicken parts, whereas the content of vitamin E varied depending on the part and cooking method. In other words, vitamin E content of wing decreased after cooking, whereas contents of thigh and leg significantly increased after cooking (P<0.05). These results are helpful for choosing the best cooking method according to the part of the chicken for proper consumption of fats and vitamins.

• Journal of Gastric Cancer
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• v.17 no.4
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• pp.283-294
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• 2017

Purpose: This study primarily aimed to investigate the short- and long-term remission rates of type 2 diabetes (T2D) in patients who underwent surgical treatment for gastric cancer, especially patients who were non-obese, and secondarily to determine the potential factors associated with remission. Materials and Methods: We retrospectively reviewed the clinical records of patients with T2D who underwent radical gastrectomy for gastric cancer, from January 2008 to December 2012. Results: T2D improved in 39 out of 70 (55.7%) patients at the postoperative 2-year follow-up and 21 of 42 (50.0%) at the 5-year follow-up. In the 2-year data analysis, preoperative body mass index (BMI) (P=0.043), glycated hemoglobin (A1C) level (P=0.039), number of anti-diabetic medications at baseline (P=0.040), reconstruction method (statistical difference was noted between Roux-en-Y reconstruction and Billroth I; P=0.035) were significantly related to the improvement in glycemic control. Unlike the results at 2 years, the 5-year data analysis revealed that only preoperative BMI (P=0.043) and A1C level (P=0.039) were statistically significant for the improvement in glycemic control; however, the reconstruction method was not. Conclusions: All types of gastric cancer surgery can be effective in short- and long-term T2D control in non-obese patients. In addition, unless long-limb bypass is considered in gastric cancer surgery, the long-term glycemic control is not expected to be different between the reconstruction methods.

• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.2
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• pp.173-180
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• 2006

Knowledge of growth and development is essential for pediatric dentistry treating growing patients. The data from the pediatric growth curve being used today does not reflect the growth transition of modern times, nor does it match the age range required for dental purposes. The present study, therefore, aims to introduce the process of producing a growth curve and growth rate curve based on data which represents a more accurate description of the present situation. The original data used in this study were from the 5th nationwide survey, SIZE KOREA 2004 study carried out by the Technology and Standards Policy Division, Department of Technology and Standards Planning, Ministry of Commerce, Industry. and Energy. Processing and rearranging the produced data with variations divided into the three quartiles and the 1st, 5th, 95th and 99th percentiles were included to produce a growth observation chart according to sex, height and weight differences. In the same way, a growth rate curve based on the geometric mean value was produced. The resulting growth charts can be used as an index for growth and development, and used for better communication between the pediatric dentist, patients or their parents.

• Tuberculosis and Respiratory Diseases
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• v.51 no.6
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• pp.503-516
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• 2001

Background : The present study was carried out in association with neutrophilic respiratory burst in the lung in order to clarify the pathogenesis of acute respiratory distress syndrome(ARDS) following acute severe hemorrhage. Because oxidative stress has been suggested as one of the principal factors causing tissue injury, the role of free radicals from neutrophils was assessed in acute hemorrhage-induced lung injury. Method : In Sprague-Dawley rats, hemorrhagic shock was induced by withdrawing blood(20 ml/kg of B.W) for 5 min and the hypotensive state was sustained for 60 min. To determine the mechanism and role of oxidative stress associated with phospholipase A2(PLA2) by neutrophils, the level of lung leakage, pulmonary myeloperoxidase(MPO), and the pulmonary PLA2 were measured. In addition, the production of free radicals was assessed in isolated neutrophils by cytochemical electron microscopy in the lung. Results : In hypotensive shock-induced acute lung injury, the pulmonary MPO, the level of lung leakage and the production of free radicals were higher. The inhibition of PLA2 with mepacrine decreased the pulmonary MPO, level of lung leakage and the production of free radicals from neutrophils. Conclusion : A. neutrophilic respiratory burst is responsible for the oxidative stress causing acute lung injury followed by acute, severe hemorrhage. PLA2 activation is the principal cause of this oxidative stress.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.4
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• pp.763-770
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• 1997

The air abrasive technique is a non-mechanical method by which teeth are treated before restoration and stains and calculi are removed from tooth surfaces using the kinetic energy of small particles. The air abrasive technique in dentistry was first introduced in the 1950's with as instrument called 'Airdent'. But, as the main restorative materials of the period were amalgam and gold, and the instrument's inability to control the flow of particles caused the particles to be spread throughout the clinics, widespread use was not possible. In the 1990's, as these techincal problems were solved and more interest in new restorative materials rose in an effort to preserve sound tooth structure, new developements took place in instruments related to the air abrasive technique. The air abrasive technique produces less pressure, vibration and heat that might cause patient discomfort and facilitates the preservation of sound tooth structure. It also reduces the need for anesthesia and is less harmful to the pulp. Other advantages include increase in dentin bonding strength of composite resin, lower possibility of saliva contamination and maintenance of a dry field. But there is not direct contact between the nozzle and the tooth, the operator cannot use his or her tactile sense and must rely solely upon visual input. Other disadvantages are: the tooth preparation depends on the operator's ability; alpha-alumina particles, after bouncing off the tooth surface, cause damage to dental mirrors; the equipment is expensive and takes up a certain amount of space in the clinic. The author conducted case report using the air abrasive technique on patient visiting the Department of Pediatric Dentistry at Seoul National University Dental Hospital and arrived at the following conclusions. 1. The tooth preparation capability of different air abrasive devices varied widely among manufacturers. 2. It was more effective in treating early caries lesions and stains compared to lesions where caries had already progressed to produce soft dentin. 3. The cold stream and noise caused by the evacuation system was a major cause of discomfort to pediatric patients. 4. As there is no direct contact with tooth surface when using the air abrasive technique for tooth preparation, considerable experience and skill is required for proper tooth preparation.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.1
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• pp.115-124
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• 2002

The purpose of this study was to establish regression equations and probability charts for predicting the sum of mesiodistal crown diameters of unerupted unilateral canine and premolars from the sum of mesiodistal crown diameters of four mandibular incisors in Korean male and female. The plaster casts of 162 children(75 boys and 87 girls) among the contestees in 1994-2001 Healthy Dentition Contest in Seoul were measured. Sex differences are compared and the following results were obtained: 1. Bilateral comparison of sum of widths of permanent canine and premolars showed no significant differences for either sex(p>0.05). Sum of widths of permanent canine and premolars of male were significantly larger than that of female(p<0.01). 2. Regression equations for the prediction of sum of widths of permanent canine and premolars in each sex were as follows Male ${\Sigma}Maxillary$ 345 y= 10.45+0.53x Male ${\Sigma}Mandibular$ 345 : y= 10.07+0.51x Female ${\Sigma}Maxillary$ 345 : y=12.65+0.42x Female ${\Sigma}Mandibular$ 345 : y=11.70+0.42x Male+female ${\Sigma}Maxillary$ 345 y=11.01+0.50x Male+female ${\Sigma}Mandibular$ 345 : y=9.87+0.51x