• Journal of electromagnetic engineering and science
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• v.3 no.1
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• pp.12-16
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• 2003

In this paper, low noise amplifiers with coplanar waveguide structure are presented for Wireless LAN data communication application. For comparison of microwave performance, LNAs of cascode type and balanced type using cascode cell with the same substrate and same bias conditions are designed and implemented. A cascode type of LNA shows the gain of 12.45 ㏈, input return loss of 11.63 ㏈, and noise figure of 1.52㏈. A balanced type of LNA using cascode cell shows the gain of 6.58 ㏈, input return loss of 16.6 ㏈, and noise figure of 1.18 ㏈.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2000.11a
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• pp.225-228
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• 2000

In this paper, the design for a low noise amplifier with the EM simulation is presented. The ATF36077 pHEMT device is applied to design LNA for U-NII frequency band (5 GHz ～ 6 GHz). The matching networks have been designed by the only open ended stub in order to reduce parasitic effects generated from a via structure. Through EM simulator, the simulation result shows that the linear gain (@5.5 GHz) is over 10 dB, input return loss and output return loss (@ 5.5 GHz) are a below 10 dB respectively, and the 3rd order intercept point is about 17 dBm.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.9 no.1
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• pp.41-55
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• 1999

In order to evaluate the effects of knowledge, attitude and practice on noise-induced hearing loss or hearing threshold level, questionnaire survey was performed and hearing thresholds of 1 kHz and 4 kHz were measured on 1,040 subjects with workers exposed to noise, safety and health officers. industrial hygienists, analysts rind office workers. The results were as follows ; 1. The following 6 factors were obtained by factor analysis and factor rotation of 30 questionnaire of knowledge, attitude and practice about noise; knowledge of noise (F1), concern of hearing protective devices (F2), concern of noise induced hearing loss (F3), concern of noise level and hearing impairment (F4), concern of noise in workplace (F5) and recognition of noised-induced hearing loss (F6). 56.1% of variance was explained by 6 factors. 2. Significant variables influencing knowledge, attitude and practice about noise were education level and age in F1, personal protective devices (PPE) and education level in F2, age and education level in F3, education level, age and sex in F4, PPE, education level, age and work duration in F5, and work duration and PPE in F6. 3. Hearing thresholds of 4 kHz were significantly higher in workers exposed to noise than that of in the other subjects and tended to be higher in industrial hygienists, safety and health officers and analysts than that of the office workers. 4. Significant variables influencing hearing thresholds of 1 kHz were age, education level, F5 and F6 in workers exposed to noise, and F1 in industrial hygienists. 5. Significant variables influencing hearing thresholds of 4 kHz were age, F6, sex, work duration, F1, F5, F2 and F3 in workers exposed to noise, F1 and age in safety and health officers, and F6, sex and F4 in industrial hygienists. With the above results, it suggested that workers exposed to noise be needed the education of knowledge, attitude and practice about noise in hearing conservation program for the prevention of noise induced hearing loss. Also, it suggested that health managers in workplace be needed countermeasures to prevent hearing loss although they are intermittently exposed to noise.

• Journal of Korean Public Health Nursing
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• v.27 no.2
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• pp.357-371
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• 2013

Purpose: The purpose of this study was to investigate the effects of health education based on the health belief model (HBM) to the prevention of noise-induced hearing loss (NIHL) in middle school students. Methods: A pretest-posttest nonequivalent control group was designed for the purpose of this study. A total of 212 students (134 in the experimental group and 78 in the control group) of two middle schools in Seoul were enrolled for the study. Health education of two 45-minutes sessions over two weeks were provided. The data were analyzed by descriptive statistics, Chi-square test, t-test, ANCOVA and repeated measures ANOVA with Bonferroni post-hoc test, using the SPSS version 21.0. Results: There were significant differences between experimental group and control group with reference to perceived susceptibility (F=7.862, p=.006), perceived severity (F=8.291, p=.004), perceived benefits (F=20.311, p<.001), and perceived barriers (F=5.628, p=.019) after health education were provided. We also observed sustained health education effects of perceived susceptibility, perceived severity, perceived benefits, and perceived barriers in the experimental group for up to 4 weeks after health education were provided. Conclusion: The health education to prevent NIHL based on the HBM improved the health beliefs of the middle school students. Health education on the HBM for the prevention of NIHL should be provided at the level of middle school.

• The Korean Journal of Community Living Science
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• v.27 no.3
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• pp.405-418
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• 2016

This study was conducted to explore the influences of loss experiences and depression on ego-integraty and transcendence of elderly Koreans and to identify gender differences in the relationships among loss experiences, depression, ego-integrity, and transcendence from 146 men and 194 women aged over 60 years in Busan, Gyeong-Nam, and Gyeong-Buk area. The main results were as follows: elderly men reported more loss experiences and transcendence than elderly women. Next, loss experiences influenced ego-integrity and depression mediated the relationship between loss experiences and ego-integrity. Also, ego-integrity had a direct effect on transcendence. Last, depression of elderly men fully mediated the relationship between loss experiences and transcendence. The relationship between loss experiences and ego-integration was partially mediated by depression for elderly women. These results were discussed in terms of gero-education and elderly welfare.

• Journal of the Semiconductor & Display Technology
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• v.19 no.1
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• pp.55-60
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• 2020

This study designed High impedance filter to reduce RF loss to heater heating wire and increase RF current flowing to heater ground wire. Effects such as D / R improvement and process reproducibility could be seen. In addition, RF parameter distribution optimization was possible by understanding the RF path of PE-CVD equipment using Plasma and designing filter.

• Korean journal of food and cookery science
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• v.12 no.4
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• pp.562-570
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• 1996

A weight control program has been prescribed to investigate its effects on weight reduction of obese adults. The prescribed weight control program has been followed by 4 overweight adults and fad diets has been followed by 6 ovenveight adults for 3 to 7 months. The prescribed weight control program was basically the low calorie diet (1,500-1,800 kcal per day) and nutrition education was applied to enhance its effects. Fad diets were chosen among the fashionable diets and they were "apple diet" , "yogurt diet" and "Lee Hijae diet" Anthropometric measurements, biochemical parameters, and percent of body fat were measured after the respective period of weight control program. Body weight was significantly (p<0.01) reduced and the rate of obesity was also significantly lowered with the prescribed weight control program while the body weight and rate of obesity were not changed with the fad diets. Weight loss from the prescribed weight control program also led to the change of total cholesterol levels while LDL-cholesterol, HDL-cholesterol, triglyceride were not significantly changed. Nutrition education and counseling of the weight control subjects induced more weight loss and better food behavior. It is suggested that a weight loss program should be based on the low calorie diet with the well-planned nutrition education The fashionable diets were attractive for a short time period in weight reduction but the rapid weight gain was noticed right after the diets ceased.

• Journal of the Korean Society of School Health
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• v.22 no.1
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• pp.107-118
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• 2009

Purpose: The purpose of this study was to investigate usage of earplones, PCPs, and to give the basic data for adolescent's hearing health education. The study was a descriptive research about three factors affecting hearing loss; the knowledge and attitude about noise, the perception of hearing loss. Method: For research purposes, we conducted a questionnaire survey of 1,480 high school students in Suwon, from 27 October 2007 to 31 2007. Result: Most of the subjets used PCPs for 3-5 years, the average time of using earphones per day was 1-3 hours, awake hearing acuity decrease after using is the hearing acuity became worse some, PCPs type is MP3, use place house, listening contents ballade, disorder condition experience after using if the ear it is sick. The average of concern about hearing scored the highest 3.01${\pm}$0.54. The average of perceived susceptibility scored 3.04${\pm}$0.63 and the average of knowledge about noise scored 2.76${\pm}$0.46. The average of total knowledge and attitude about noise scored 2.93${\pm}$0.52. The average of discomfort of hearing loss(2.20${\pm}$0.63) scored higher than that fear of hearing loss(1.66${\pm}$0.30). The average of total perception of hearing loss scored 2.12${\pm}$0.67. Conclusion: At least in this study are shown in the youth earphone, PCPs used as a spare because of the seriousness of the issue, so as a result of these problems related to hearing about the youth campaign, through advertising or seriousness of the young people need them. In addition, countries also need to create policies and the support for health education, especially during the regular curriculum subjects on subjects that include teenagers in the earphone, PCPs due to problems with spare on the contents of the reservoir. The severity of hearing loss young people, prevention of hearing to protect the youth.

• Journal of Korean society of Dental Hygiene
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• v.9 no.4
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• pp.784-794
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• 2009

Objectives : This study was to prepare basic data about middle and high school students' school loss due to oral diseasea and to investigate the relevant factors. Methods : The survey is conducted for 575 middle school students in Busan and Gyeongnam. School loss was investigated based on the experiences of absences and leaving school early, which had happened from oral diseasea. The independent variables were oral health behaviors and sociopeconomic factors such as sex, age of their parents, educational level of their parents, family income. Factors related with school loss was analyzed by the multiple logistic regression method. Results : The experience ratio of leaving school early to the dental clinic or having difficulty in studying was higher in the case of high school student than in middle school student case. The parameters related with absence or leaving school early for oral disease were the education level, the distinction of sex, fear about medical examination and the standard of living. The reasons of absence or leaving early for visiting the dental clinic were related with education level, the distinction of sex, fear about medical examination, distrust of oral care and the satisfaction of oral health. The parameters having effect on school performance were education level, sex, fear about medical examination, distrust of oral care, cost burden, interests in oral health by the parents and school record. Conclusions : The oral health promotion should be developed to decrease school loss for students.

• BMB Reports
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• v.51 no.4
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• pp.200-205
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• 2018

Exercise and resveratrol supplementation exhibit anti-obesity functions in the long term but have not been fully investigated yet in terms of their early potential effectiveness. Mice fed with high-fat diet were categorized into control (Cont), exercise (Ex), resveratrol supplementation (Res), and exercise combined with resveratrol supplementation (Ex + Res) groups. In the four-week period of weight loss, exercise combined with resveratrol supplementation exerted no additional effects on body weight loss but significantly improved whole-body glucose and lipid homeostasis. The combined treatment significantly decreased intrahepatic lipid content but did not affect intramyocellular lipid content. Moreover, the treatment significantly increased the contents of mtDNA and cytochrome c, the expression levels of peroxisome proliferator-activated receptor gamma coactivator-1 alpha and its downstream transcription factors, and the activities of ATPase and citrate synthase. However, exercise, resveratrol, and their combination did not promote myofiber specification toward slow-twitch type. The effects of exercise combined with resveratrol supplementation on weight loss could be partly due to enhanced mitochondrial biogenesis and not to fiber-type shift in skeletal muscle tissues.