• Journal of Korean Home Economics Education Association
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• v.28 no.4
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• pp.159-167
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• 2016

This study was performed to investigate the relationship between milk consumption, dietary nutrient intake, and physical strength in Korean adolescents for dietary education of home economics subject at middle and high schools. Intake of milk and milk products, that of dietary nutrients, and physical strength records were surveyed for 298 high school students resided in small and medium-sized cities in Korea. Intake of milk and milk products was collected from three-day dietary survey, and daily dairy equivalent of calcium was calculated by dividing daily calcium intake(mg) from milk and milk products by calcium content(200 mg) of 200 mL milk. Dietary survey was performed during three days including two-weekdays and one-weekend by food record method. Dietary nutrient intake was analyzed by CAN-Pro 3.0. Physical strength records were offered from subjects' schools. Subjects were divided into low intake group(${\leq}0.29/d$), medium intake group(0.30-0.78/d) and high intake group(0.79-5.66/d) according to daily mean dairy equivalent of calcium taken by them, and most of them consumed milk and milk products less than '2' of the recommended value. Daily mean dairy equivalent of calcium was significantly related with high records of '50 m running' and 'stand long jump'(p<0.05), however it was not related with other records of physical strength. Intakes of energy, carbohydrate, protein, fat, calcium, phosphorus, iron, zinc, thiamin, riboflavin, niacin and vitamin E were significantly correlated with high record of '50 m running'(p<0.01). Intakes of nutrients were related with '50 m running' except fat were significantly correlated with high record of 'stand long jump'(p<0.05). Intakes of protein, phosphorus, iron, zinc, vitamin A, $B_6$ and E were significantly correlated with high record of 'long distance running'(p<0.05). In conclusion intake of milk and milk products was related with physical strength records('50 m running' and 'stand long jump') and intakes of most nutrients including energy nutrient, vitamin and mineral were correlated with physical strength records('50 m running', 'stand long jump' and 'long distance running') in Korean adolescents. Therefore, optimal consumption of milk and various nutrients for balanced nutrition during adolescents should be emphasized in dietary education of home economics subject for their strong physical strength.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.310-310
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• 2014

ZnO박막은 넓은 밴드갭 (3.37 eV), 높은 여기 결합 에너지 (60 meV)를 가지는 육방정계 우르자이트(hexagonal wurtzite) 결정구조를 가지는 II-VI족 화합물 반도체로, 가시광선 영역에서의 높은 광학적 투과도 특성과 자외선 파장에서 발광이 가능한 장점을 가진다. 최근, ZnO박막 성장 기술이 상당히 발전하였지만, 아직까지도 p-형 ZnO박막 성장 기술은 충분히 발전하지 못하여 ZnO의 동종접합 LED는 아직 상용화되지 않고 있는 실정이다. 따라서, 많은 연구 그룹에서 p-GaN, p-SiC, p-diamond, p-Si 등과 같은 p-type 물질 위에 n-type ZnO를 성장시킨 이종접합 다이오드가 연구되고 있다. 특히, p-GaN의 경우 ZnO와의 격자 불일치 정도가 1.8 % 정도로 작다는 장점이 있어 많은 연구가 이루어 지고 있다. 일반적으로 c-축을 기반으로 한 극성ZnO 발광다이오드에서는 자발 분극과 압전 분극 현상에 의해 밴드 휨 현상이 발생하고, 이로 인해 전자와 정공의 공간적 분리가 발생하게 되어 발광 재결합 효율이 제한되고 있다는 문제가 발생한다. 따라서, 본 연구에서는 극성 (0001) 및 비극성 (10-10) n-ZnO/p-GaN 발광다이오드의 성장 및 발광 소자의 전기 및 광학적 특성에 대한 비교 연구를 진행하였다. 금속유기 화학증착법을 이용하여 c-면과 m-면 위에 각각 극성 (0001) 및 반극성 (11-22) GaN박막을 $2.0{\mu}m$ 성장시킨 후 Mg 도핑을 한 p-GaN을 $0.4{\mu}m$ 성장시켜 각각 극성 (0001) 및 반극성 (11-22) p-GaN템플릿을 준비하였다. 이후, N2분위기 $700^{\circ}C$에서 3분동안 열처리를 통하여 Mg 도펀트를 활성화시킨 후 원자층 증착법을 이용하여 동시에 극성 및 반극성 p-GaN의 위에 n-ZnO를 $0.11{\mu}m$ 성장시켜 이종접합구조의 발광소자를 형성하였다. 이때, 극성 (0001) p-GaN 위에는 극성의 n-ZnO 박막이 성장되는 반면, 반극성 (11-22) p-GaN 위에는 비극성 (10-10) n-ZnO 박막이 성장됨을 HR-XRD로 확인하였다. 극성 (0001) n-ZnO/p-GaN이종접합 발광다이오드의 전계 발광 스펙트럼에서는 430 nm 와 550 nm의 두 피크가 동시에 관찰되었다. 430 nm 대역의 파장은 p-GaN의 깊은 준위에서 발광하는 것으로 판단되며, 550 nm 피크 영역은 ZnO의 깊은 준위에서 발광되는 것으로 판단된다. 특히, 10 mA 이하의 저전류 주입시 550 nm의 피크는 430 nm 영역보다 더 큰 발광세기를 나타내고 있다. 하지만, 10 mA 이상의 전류주입 하에서는 550 nm의 영역보다 430 nm의 발광세기가 더욱 증가하는 것을 확인할 수 있었다. 이것은 ZnO의 밴드갭이 3.37 eV로 GaN의 밴드갭인 3.4 eV다 작기 때문에 우선적으로 ZnO의 깊은 준위에서 발광하는 550 nm가 더욱 우세하지만, 지속적으로 전류주입 증가에 따른 캐리어 증가시 n-ZnO에서 p-GaN로 전자가 넘어가며 p-GaN의 깊은 준위인 430 nm에서의 피크가 우세해지는 것으로 판단된다. 반면에, 비극성 (10-10) n-ZnO/반극성 (11-22) p-GaN 구조의 이종접합 발광다이오드로 전계 발광 스펙트럼에서는 극성 (0001) n-ZnO/p-GaN에 비하여 매우 낮은 전계 발광 세기를 나타내고 있다. 이는, 극성 n-ZnO/p-GaN에 비하여 비극성 n-ZnO/반극성 p-GaN의 결정성이 상대적으로 낮기 때문으로 판단된다. 또한, 20 mA 영역에서도 510 nm의 깊은 준위와 430 nm의 발광이 관찰되었다. 동일한 20 mA하에서 두 피크의 발광세기를 비교하면 430 nm의 영역은 극성 n-ZnO/p-GaN에 비하여 매우 낮은 값을 나타내고 있다. 이는 반극성 (11-22) p-GaN의 경우 극성 (0001) p-GaN에 비하여 우수한 p-형 특성에 기인한 것으로 판단된다.

• Archives of design research
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• v.19 no.4 s.66
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• pp.133-144
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• 2006

According to the latest report by the Customer Protection Board, those who moved into newly constructed buildings are complaining about unidentified pains, asking for more careful selection of constructive materials for prevention of such potential problems. It is internationally recognized today that ecological materials can serve a significant factor for users' health, environmental protection and better industrial competitiveness. This study examined eco-design aspects of each interior material through web site search, in order to help customers learn about and capitalize on eco materials in a proper manner. As a result, 1. It turned out that the domestic industry are giving an impetus to releasing new eco items focusing on lower VOCs emission or addition of functional components as part of the marketing strategy. However, it is recommended that company understand significance of life cycle, and produce eco-concept materials. 2. The reliable standard for choosing the domestic material is EL, HB, GR marks. It is desirable to enhance recycling technologies and expand the sustainable consumption. customer class, since many recycled items are not developed. 3. The sourcing is a vulnerable part in terms of the concept of being environment-friendly material. Therefore, many manufacturers should design the easy knock-down products and produce the good items using recycled materials instead of new raw materials. Also solutions for making the energy from burning material should be studied. 4. The guidebook or manual with correct information about eco-materials is required to promote production and consumption with sustainable concept. 5. Many manufacturers are emphasizing ecological materials for customers, but some of them intended to disrupt customers' proper selection by promoting even unverified items to be environment-friendly.

• The Korean Journal of Nuclear Medicine Technology
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• v.15 no.1
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• pp.90-93
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• 2011

Purpose: A Pixelated BSGI gamma camera has features to enhance resolution and sensitivity and minimize the distance between detector and organs by narrow FOV. Therefore, it is known as useful device to examine small organs such as thyroid, parathyroid and gall bladder. In general, when we would like to enlarge the size of images and obtain high resolution images by gamma camera in nuclear medicine study, we use pinhole collimator. The purpose of this study is to evaluate the usefulness of Pixelated BSGI gamma camera and to compare to it using pinhole collimator in thyroid scan which is a study of typical small organs. Materials and methods: (1) The evaluation of sensitivity and spatial resolution: We measured sensitivity and spatial resolution of Pixelated BSGI with LEHR collimator and Infinia gamma camera with pinhole collimator. The sensitivity was measured by point source sensitivity test recommended by IAEA. We acquired images considering dead time in BSGI gamma camera for 100 seconds and used $^{99m}TcO4-\;400{\mu}Ci$ line source. (2) The evaluation of thyroid phantom: The thyroid phantom was filled with $^{99m}TcO4-$. After set 300 sec or 100 kcts stop conditions, we acquired images from both pixelated BSGI gamma camera and Infinia gamma camera with LEHR collimator. And we performed all thyroid studies in the same way as current AMC's procedure. Results: (1) the result of sensitivity: As a result, the sensitivity and spatial resolution of pixelated BSGI gamma camera were better than Infinia's. The sensitivities of pixelated BSGI and Infinia gamma camera were $290cps/{\mu}Ci$ and $350cps/{\mu}Ci$ respectively. So, the sensitivity of pixelated BSGI was 1.2 times higher than Infinia's (2) the result of thyroid phantom: Consequently, we confirmed that images of Pixelated BSGI gamma camera were more distinguishable between hot and cold spot compared with Infinia gamma camera. Conclusion: A pixelated BSGI gamma camera is able to shorten the acquisition time. Furthermore, the patients are exposed to radiation less than before by reducing amount of radiopharmaceutical doses. Shortening scan time makes images better by minimizing patient's breath and motion. And also, the distance between organ and detector is minimized because detector of pixelated BSGI gamma camera is small and possible to rotate. When patient cannot move at all, it is useful since device is feasible to move itself. However, although a pixelated BSGI gamma camera has these advantages, the effect of dead time occurs over 2000 cts/s since it was produced only for breast scan. So, there were low concentrations in organ. Therefore, we should consider that it needs to take tests to adjust acquisition time and amount of radiopharmaceutical doses in thyroid scan case with a pixelated BSGI gamma camera.

• Journal of the Korean Society of Radiology
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• v.9 no.3
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• pp.147-168
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• 2015

In this research, we have analyzed the impact factors on the bone mineral density thru the examination of bone density difference in the entire femur, femoral neck and lumbar of adult women before the menopause in accordance with the general features, lifestyle, eating habits, health and body composition. The survey was conducted among adult women before the menopause and older than 30 years based on the data of the National Health and Nutrition Examination Survey carried out in the 4th term (2008-2009) and 5th term (2010-2011) and we would like to provide the research results for the establishment of recommendations or guidelines for the treatment of adult women before the menopause with regard to the impact factors on the bone mineral density and for the development of health education materials for the accurate measurement of bone mineral density of young women in order to prevent the postmenopausal osteoporosis. With respect to the general features of adult women before the menopause, the bone mineral density was higher in the entire femur at age 40-44, femoral neck at 35-39, in high-school education level, in the earlier menarche group, without smoking experiences, with regular walking time and exercise frequency and with the habits of eating no hamburger or pizza. With regard to the body composition, the bone mineral density was higher in obesity and lower in underweight cases, higher among people with abdominal obesity and weight control experiences. In terms of total body fat ratio, total amount of fat and muscle, the bone mineral density got gradually increased from the 1st quarter (Q1) to the 4th quarter(Q4). The obesity, disease, total amount of fat and muscle were shown to be significantly related with the bone mineral density in this research and it is required for young women to keep the adequate weight and the normal BMI in order to increase the bone mineral density. For the prevention of osteoporosis, it is advised to keep the right habits including regular exercise and no smoking discipline from the growing period and achieve the maximum bone mass thru the control of proper weight from a young age.

• Radiation Oncology Journal
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• v.25 no.3
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• pp.185-191
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• 2007

Purpose: This study was performed to investigate the effects of immune cell activation and the antitumor effect for the combination of treatment with X-irradiation and E/eutherococcus senticosus Maxim Root (ESMR) on mouse tumor cells. Materials and Methods: ESMR (250g) was extracted with 80% methanol, concentrated under decompression and lyophilized. To determine whether ESMR is able to activate the immune cells or not, the proliferation of splenocytes in vitro and the number of B cells and T cells in splenic lymphocytes in ESMR-pretreated mice were evaluated. X-irradiation was given to the mouse fibrosarcoma tumor cells (FSa II) by 250 kv X-irradiation machine. The cytotoxicity of ESMR was evaluated from its ability to reduce the clonogenecity of FSa II cells. In X-irradiation alone group, each 2, 4, 6 and 8 Gy was given to FSa II cells. In X-irradiation with ESMR group, 0.2 mg/ml of ESMR was exposed to FSa II cells for 1 hour before X-irradiation. Results: The proliferation of cultured mouse splenocytes and thymocytes were enhanced by the addition of ESMR in vitro. The number of B cells and T cells in mouse splenic lymphocytes was significantly increased in ESMR pretreated mice in vivo. In FSa II cells that received a combination of 0.2 mg/ml of ESMR with X-irradiation exposure, the survival fraction with a dose of 2, 4 and 6 Gy was $0.39{\pm}0.005$, $0.22{\pm}0.005$ and $0.06{\pm}0.007$, respectively. For FSa II cells treated with X-irradiation alone, the survival fraction with a dose of 2, 4 and 6 Gy was $0.76{\pm}0.02$, $0.47{\pm}0.008$ and $0.37{\pm}0.01$. The difference in the survival fraction of the mouse FSa II cells treated with and without ESMR was statistically significant (p<0.05). Conclusion: Treatment with ESMR increased cell viability of mouse splenocytes in vitro and especially the subpopulation of B cells and T cells in splenocytes in ESMR-pretreated mice. However, treatment with ESMR did not increase the level of Th and Tc subpopulations in the thymocytes. Treatment with the combination of ESMR and X-irradiation was more cytotoxic to mouse tumor cells than treatment with X-irradiation alone; this finding was statistically significant.

• Journal of The Korean Society of Grassland and Forage Science
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• v.12 no.3
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• pp.3-12
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• 1992

Forage grasses and legumes ar$\varepsilon$ the mam component of livestock diets in Canada. There are over 30 million ha of grassland in Canada and there is a large, undeveloped land base in fringe areas suitable for forage production. The short growing s season limits the grassland farming to the southern p parts of Canada. The win!er season is long and in most parts of Canada cold temperatures, fr$\varepsilon$ezmg, and thawing, and diseases exert sever$\varepsilon$ stress on overwintering forage plants. The development of persistent cultivars is essential for sustained production particularly in the fringe areas with short growmg s$\varepsilon$ason. The seasonality of dry matter production is a result of high growth rates in early summ$\varepsilon$r and low dry matter accumulation in late summer and fall. Innovative management practIces a and cultivars with improved regrowth capacity are n necessary to overcome such skewed production pattern and to extend effiectlVe grazmg season l Improved pasture production is an important part of reducing costs in livestock operations and remaining competitive. It is suggested that applying available technology would increase pasture productivity and reduce d$\varepsilon$pendence on stored feeds thus improving profitability of small producers in particeular. Reducing nutrient losses during harv$\varepsilon$stmg, s storage, and feeding is essential for improved production efficiency during confinement. The devclopment of low cost and labor saving methods of ensiling is critical for improved efficiency and profitability of forage based enterprises Livestock industries must respond to consumer preferences for low fat and cholesterol foods. Research and development of entire production systems is emphasized for dev$\varepsilon$loping viabl$\varepsilon$ enterprises. It is increasingly difficult to secure resources for r$\varepsilon$search, education, and extension, and alliane$\varepsilon$s and cooperation must expand among organizations with interests in forage based livestock systems.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.1
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• pp.61-71
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• 2000

When irradiate the power ultrasound into the aqueous solutions, water vapor is decomposed by the heat of very high temperature in the cavitation bubble to produce OH (hydroxyl radical) and H (hydrogen radical), and these radicals play a role in decomposing the substances in aqueous solution by oxidation and/or reduction, and in producing the hydrogen peroxide. Accordingly it is possible to predict that the quantity of hydrogen peroxide produced may correlate with the sonolysis mechanism of the substance in aqueous solution. Thus to confirm this prediction, the quantities of hydrogen peroxide produced from each of the air saturated distilled water and three aqueous solutions of TCE, benzene, and 2,4-DCP that are prepared by dissolving them into distilled water are measured. As a result, it showed that the quantity of hydrogen peroxide produced from the distilled water and three aqueous solutions are increased in order of distilled water>TCE solution>2,4-DCP solution>benzene solution, and decrease with decrease in concentration of organic substance, which coincide with the sonolysis mechanisms reported that TCE in aqueous solution is decomposed directly by the pyrolysis in and around the cavitation bubbles when its concentration is high and by the radical reaction when low, however, benzene and 2,4-DCP are decomposed not only by the pyrolysis but also by the radical reactions. Effects of such experimental parameters as the acoustic frequency and power and as the concentration showed that the higher the acoustic frequency and the lower the acoustic power, the less the quantity of hydrogen peroxide was produced. This result coincide with the theory of ultrasound for the relation between the cavitation that is the energy source of the power ultrasound in aqueous solution and these experimental parameters.

• Korean Journal of Psychosomatic Medicine
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• v.24 no.2
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• pp.191-199
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• 2016

Objectives : Despite the increased popularity of highly caffeinated beverages, there is little research examining psychiatric adverse effects. The purpose of this study was to investigate the relationships among pattern of highly caffeinated beverage intake and depressive symptom, suicidal ideation, suicidal plan, suicidal attempt in Korean adolescents. Methods : The data was obtained from the 2014 Korean Youth's Risk Behavior Web-based Study by Korea Centers for Disease Control & Prevention. All participants conducted web-based questionnaire survey. Chisquare test and multiple logistic regression analysis were performed to determine the association among highly caffeinated beverage intake pattern, depressive symptom, suicidal ideation, suicidal plan and suicidal attempt adjusting for differences in age, gender, academic achievement, socioeconomic status. Results : A total of 71,638 participants were enrolled in this study. Depressive symptom, suicidal ideation, suicidal plan and suicidal attempt were significantly more frequent in the group with presence of highly caffeinated beverage intake within 1 week than in non-drinker group(p<0.01). Highly caffeinated beverage intake was significantly associated with suicidal attempt(OR=1.99 ; 95% CI, 1.77-2.22). In addition, depressive symptom, suicidal ideation, suicidal plan and suicidal attempt were significantly more common in the group with heavy-drinker who exceed recommended daily intake dose of caffeine than in the group with light-drinker(p<0.01). Heavy drinking of caffeinated beverage was significantly associated with suicidal attempt(OR=4.05 ; 95% CI, 3.02-5.43). Conclusions : We found that highly caffeinated beverage intake was related to more frequent depressive symptom, suicidal ideation, plan, attempt in adolescents. Also, caffeine intake which exceed recommended daily intake dose identified the predictor of suicidal attempt. Our result suggested that clinicians need to be aware of the possible psychiatric adverse effects of highly caffeinated beverage in vulnerable population including young adolescents.

• Clean Technology
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• v.27 no.4
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• pp.359-366
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• 2021

Halloysite nanotubes (HNTs), the multiwalled clay mineral with the composition of Al₂Si₂O₅(OH)₄·nH₂O, have been highlighted as a low-cost adsorbent for the removal of dyes from wastewater. Although a powder of halloysite presents a high specific surface area, forming media are significantly considered due to sludge-clogging induced by the water-bound agglomeration. However, higher firing temperature to achieve the structural durability of the media and lower utilization rate due to longer penetration depth into the media act as hurdles to increase the dye-adsorption capacity. In this work, the retention of the adsorption capacity of halloysite was evaluated with methylene blue solution after the heat treatment at 750 ℃. In order to improve the utilization rate, tubular media were fabricated by extrusion. The images taken by transmission electron microscopy show that HNTs present excellent structural stability under heat treatment. The HNTs also provide superb capacity retention for MB adsorption (93%, 18.5 mg g^-1), while the diatomite and Magnesol^® XL show 22% (7.65 mg g^-1) and 6% (11.7 mg g^-1), respectively. Additionally, compositing with lignin enhances adsorption capacity, and the heat treatment under the hydrogen atmosphere accelerates the adsorption in the early stage. Compared to the rod-type, the tubular halloysite media rapidly increases methylene blue adsorption capacity.