• 한국수산과학회지
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• 제53권3호
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• pp.456-463
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• 2020

The diet of the walleye pollock Gadus chalcogrammus, was studied by examining the stomach contents of 864 individuals. Using gill nets, samples were collected monthly from January to December 2017 in Jugwang, Sokcho, Yangyang, Uljin, Ganggu, and Gampo, Korea. The specimens ranged in total length (TL) from 16.6 to 75.2 cm. G. chalcogrammus fed mainly on Euphausia pacifica (Euphausiacea) and less on Cephalopoda, Pisces, Mysidacea, and Macrura. The results indicated that G. chalcogrammus is a specialist feeder, feeding mainly Euphausiacea. With growth, however, its diet shifted from Euphausiacea to Cephalopoda, Macrura and Pisces. Smaller individuals (<40.0 cm TL) consumed mainly Euphausiacea. The proportion of Euphausiacea decreased with increasing body size, whereas the consumption of Cephalopoda and Macrura increased gradually.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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• pp.1103-1107
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• 2007

Highly efficient organic electroluminescent devices (OLEDs) based on 4,7- diphenyl-1, 10- phenanthroline (BPhen) as the electron transport layer (ETL), tris (8-hydroxyquinoline) aluminum ($Alq_3$) as the emission layer (EML) and N,$\acute{N}$-bis-[1-naphthy(-N,$\acute{N}$diphenyl-1,1´-biphenyl-4,4´-diamine)] (NPB) as the hole transport layer (HTL) were developed. The typical device structure was glass substrate/ ITO/ NPB/$Alq_3$/ BPhen/ LiF/ Al. Since BPhen possesses a considerable high electron mobility of $5\;{\times}\;10^{-4}\;cm^2\;V^{-1}\;s^{-1}$, devices with BPhen as ETL can realize an extremely high luminous efficiency. By optimizing the thickness of both HTL and ETL, we obtained a highly efficient OLED with a current efficiency of 6.80 cd/A and luminance of $1361\;cd/m^2$ at a current density of $20\;mA/cm^2$. This dramatic improvement in the current efficiency has been explained on the principle of charge balance.

• 동아시아식생활학회지
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• 제12권4호
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• pp.299-306
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• 2002

This study was undertaken to compare the obesity related dietary factors among rural middle school students living in the Daegu.Kyungbuk area. Anthropometric data showed that mean height and weight were 162.7$\pm$8.6cm and 53.9$\pm$9.8kg in 220 male students and 158.4$\pm$6.2cm and 51.0$\pm$7.6kg in 210 female student. Mean BMIs for boys and girls were 19.00$\pm$2.35 and 19.30$\pm$2.45, respectively. 71.36% of male students and 71.9% of female students were underweight by the BMI index. Students who skipped the breakfast were up to 66.8%. The reasons for skipping a meal for both sexes were significantly different. Compared to males, more female respondents felt guilty and depressed related to eating. Furthermore, females were more significantly concerned about body image, diet and body weight (p<0.001), and they were not satisfied with their weight. The sources of information on obesity and diet were radio and TV in males, while females gathered information from magazines and friends. The ideal body weight of male students was heavier than the actual body weight while female students desired a thinner body shape. In conclusion, a different approach for nutrition education based on sex should be developed, and implemented fur adolescents.

• 전기화학회지
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• 제15권3호
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• pp.149-153
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• 2012

The $Cu_2O/TiO_2$ inverse opal heterojunction arrays were developed by electrochemical deposition of $Cu_2O$ nanoparticles on $TiO_2$ inverse opal arrays. The $Cu_2O$ nanoparticles completely filled the inner pores of $TiO_2$ inverse opal film (prepared by liquid phase deposition with an average thickness of 400 nm) and covered the entire area; exhibiting high crystalline properties of anatase and cubic phase from $TiO_2$ and $Cu_2O$, respectively. From asymmetric current-voltage profile, it was noticeable that a heterojunction was well formed for charge transport from $Cu_2O$ to $TiO_2$ film resulting from the enhanced charge separation yield. In addition, increased photocurrent of 0.19 $mA/cm^2$ (versus 0.08 $mA/cm^2$ under dark condition) was obtained at -0.35 V from the heterojunction structure in the 0.5M $Na_2SO_4$ solution.

• 한국식품영양학회지
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• 제19권4호
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• pp.343-351
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• 2006

This study was conducted to investigate food habits and eating behavior of preschool children. Food habit, eating behavior and health status were investigated by using a questionnaire answered by the mothers of 312 children aged 6 to 7 years old who lived in Uiwang. The average height, weight, Kaup index were 115.08cm, 21.41 kg, 16.13, respectively, for boys 111.37 cm, 19.93 kg, 15.72 for girls. Results showed that 72.16% of subjects skipped the breakfast meal. One of the main reason fur skipping breakfast was 'no appetite'(53.14%). It was found that 49.67% of the subjects belonged to 'good' in health status. The eating behavior of 'watching TV or playing a toy during meal' and 'can eat the rice by oneself were significantly higher score in girls than in boys(p<0.05). Food attention of the parents for the health of children was the highest in 'keep regular meals a day'(92.65%). Health status showed significantly negative correlations with kaup index and eating behavio(p<0.001). Kaup index(p<0.05) and health attention(p<0.001) were positively related with eating behavior. Based on this study, nutritional education program for preschool children would be required for the dietetics teacher to guide the children and more attention should be paid to the nutritional education of food habits in this age group and their mothers.

• 수산해양교육연구
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• 제18권1호
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• pp.58-64
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• 2006

In order to examine the effect of humidity on hydrogen embrittlement of STS 444 weld zone for boiler with dry and wet welding conditions, this paper was carried out the accelerated hydrogen osmosis test and the electrochemical Tafel polarization test. In 0.5M $H_2SO_4$ + 0.01M $As_20_3$ solution, this test is added to load of $1400kg/cm^2$ together with hydrogen osmosis by current of $50 {mA/cm^2}$ for 60 min.. The electrochemical Tafel polarization test was carried out in 0.5M $H_2SO_4$ + 0.01M $As_20_3$ solution. Therefore, the effect of humidity on hydrogen embrittlement of STS 444 was considered. The main results are as following: On the basis of hydrogen embrittlement mechanism, that is, integrated electrochemical polarization characteristics with the established mechanism of hydrogen embrittlement, the reduction rate of corrosion current density of weld zone in the wet weld condition is larger than in the dry condition. We can nondestructively predict the degree of hydrogen embrittlement of STS 444 weld zone for boiler through the reduction rate of electrochemical corrosion current density.

• The Korean Journal of Ecology
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• 제2권1호
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• pp.9-14
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• 1978

The study was made to expand the knowledge of the ecology of Cobitis koreensis which is very common in the upper and middle part of rivers in western part of Korea. A number of C. koreensis are found in the creek of Jeonju-cheon located at Segjang-ri, Wanju-gun, Jeonrabug-do Province. The area studied has pebble bottoms. The flow velocity of the river ranges from 20cm to 40cm per second under normal conditions. The sex ratio of male to female was 1:1.34 and the female was 10~25mm larger than the male in total length. Length-frequencies in this population indicate that 20~40 mm fish group is underyearling, 40~60mm is a yearling, and 60~85mm is two-year-old. And the fish longer than 90mm in total length is regarded as being over three-year-old. Based on the ratio of gonadal weight to body weight, spawning in this species began in April and expanded well into June with water temperature 20~26。C, and the individuals became sexually mature over the two-year-old. The number of the eggs was counted from ten matured female fishes. The mean number of eggs in seven 72.6~81.4mm fishes was 908 (595-1, 229) and that of the rest three 86.0~89.0mm was 1, 674 (1, 337-2, 023). The contents of stomach in the other fifteen specimens captured in September 1977 were investigated. While the younger fed almost on the algae, the foods in the adult were largely aquatic insects.

• 한국가정과교육학회지
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• 제7권1호
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• pp.133-148
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• 1995

Recently, childhood obesity is increasing in Korea mainly due to westernized dietary pattern. The purpose of this study is to investigate diet pattern(habit and behavior), nutritional knowledge and taste favor in normal and obese children. We carried out anthropometries and self questionaire about life style among the 5th-grader in elementary school(88 boys, 102 girls) in Seoul. The results are as follows : Physical conditions are boys’average hight and weight 142.0cm, 37.5kg ; and girls’143.7cm, 35.6kg. BMI are normal group 38.7% and abnormal group 61.3%(obese 24.2% underweight 16.1% overweight 14.0% very underweight 7.0%) A great part of obese children live in apartment house(79.5% of obese children in southern Seoul; 60.2% in northern Seoul). Obese parents have obese children. Diet behavior, diet pattern, food habit and food preferance of children are similar to their parents, especially their mothers. Preferance in taste of children follows in order of hot, sweet and mild. Especially obese children favor sweet taste more than others. The 61% of them are interested in weight control. Their nutritional knowledges are poor(4.9/10). They like more westernized food(hamberger) than korean food(In-jul-me).

• Journal of information and communication convergence engineering
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• 제14권4호
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• pp.207-214
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• 2016

In this paper, we propose a radial reference map-based location fingerprinting technique with constant spacing from an access point (AP) to all reference points by considering the minimum dynamic range of the received signal strength indicator (RSSI) obtained through an experiment conducted in an indoor environment. Because the minimum dynamic range, 12 dBm, of the RSSI appeared every 20 cm during the training stage, a cell spacing of 80 cm was applied. Furthermore, by considering the minimum dynamic range of an RSSI in the location estimation stage, when an RSSI exceeding the cumulative average by ${\pm}6dBm$ was received, a previously estimated location was provided. We also compared the location estimation accuracy of the proposed method with that of a conventional fingerprinting technique that uses a grid reference map, and found that the average location estimation accuracy of the conventional method was 21.8%, whereas that of the proposed technique was 90.9%.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 C
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• pp.1518-1520
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• 2002

Purpose of this research compares best transfer speed about applied frequency and voltage using characteristic of $L_1-B_4$ mode and $L_1-B_8$ mode linear ultrasonic motor that use piezoelectric effect. By method of study, analyzed best transfer speed measuring and comparison load status that use actuality telephone card in $L_1-B_4$ mode linear ultrasonic motor and no-load status of $L_1-B_8$ mode linear ultrasonic motor. Experiment result is applied frequency(58.4Hz) in $L_1-B_4$ mode linear ultrasonic motor (load state) and the best transfer speed by 19.8[cm/s] at applied voltage(56V) point. Also, $L_1-B_8$ mode linear ultrasonic motor (no-load state) is best transfer speed by applied frequency(27.9kHz) and 32.96[cm/s] at applied voltage (50V) point.