• 한국유체기계학회 논문집
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• 제17권5호
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• pp.67-71
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• 2014

Recently, the cross flow turbine attracts more and more attention for its good performance over a large operating regime at off design point. This study adopts a very low head cross flow turbine that has barely been studied before, and investigates the effect of air layer on the performance of the cross flow turbine. As open duct is applied in this study and free surface model is used between the air layer and water, an engineering definition of efficiency, instead of traditional definition of efficiency, is used. As torque at the runner fluctuates up and down at a reasonable limit, statistical method is used. Pressure and water volume fraction contours are shown to present the characteristics of air-water flow. With constant air suction in the runner chamber, the water level gradually drops below the runner and efficiency of the turbine can be raised by 10 percent. All considered, the effect of air layer on the performance of turbine is considerable.

• 한국토양비료학회지
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• 제46권6호
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• pp.575-578
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• 2013

Rice cultivation in the paddy field and the burning of crop residues have been identified as the important sources of methane emission in agricultural sector. This study aimed at assessment of the methane emission from croplands in the year of 2011 with the IPCC guideline methodology. Methane from rice cultivation was emitted 6,813 $CO_2$-eq Gg in 2011. According to the water management, methane emission amounts by continuously flooded and intermittently flooded were 1,499 and 5,314 $CO_2$-eq Gg, respectively. Methane emission by crop residues burning was highest in red pepper and followed by rice straw, pulses and barely in 2011. Methane emission by field burning was very little compared with rice cultivation.

• 동아시아식생활학회지
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• 제23권6호
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• pp.671-680
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• 2013

This study was conducted to examine the consumption realities of processed food and the perception of food labeling with targets of university students attending schools in Daegu and Gyeongbuk areas. The reason for buying processed food was because it is easy to cook. As for the number of using processed food, it was answered that everyday dairy products, noodles, breads and snacks for 3~4 times a month, and meat processed foods, canned foods, sauces and frozen foods for 2~3 times a month. With regard to selecting processed products, both male and female students answered with taste and price first, barely considering the safety and nutritional elements. It turned out that they check the price, expiration date and country of origin in order upon buying processed foods. Most of them recognized food labeling, but answered that they checked it sometimes in order to check the 'expiration date' and the 'calories'. They were aware of the food nutritional contents indication. It was turned out that male students check it for nutrients and female students for weight control. The effect of the processed food indication was that it is easy to choose the necessary foods for health and as well as for comparing the food with other products. The satisfaction of the food labeling system was mediocre. The results indicated that the food indication system needs to be educated or promoted.

• 한국군사과학기술학회지
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• 제20권5호
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• pp.654-664
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• 2017

The temperature profiles upon high speed impact of reactive structural materials were analyzed. A two color pyrometer, which included high-speed camera, spectral splitter, and band pass filters, was utilized to measure transient temperature profiles during and after reactive metal samples impacted into steel plate with velocities of 1600~1700 m/s. The spatial temperature distribution was analyzed from the ratio of spectral radiances at two different wavelength in infrared zone, i.e. 700 and 900 nm. The measured temperatures were calibrated with black body source. Two different types of metal samples, namely aluminum and nickel, were employed to understand reaction behavior upon the impact of samples in ambient condition. According to our experiments, the Ni sample appeared to barely react with ambient air producing an instant small fireball, while Al sample reacts violently with air generating a relatively prolong fireball.

• KIEAE Journal
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• 제15권1호
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• pp.53-60
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• 2015

Increase in energy consumption in building is a big concern world over. In Nepal, energy crisis is a big issue but energy demand in buildings is barely even thought about. In the southern part of Nepal, where the weather is mostly hot during the year, cooling in buildings is very important. This is an initial study regarding building design strategies which focuses on cooling energy consumption in the building. It can be seen from the study that simple passive strategies can be applied in building design which can support in decreasing cooling load. Different passive cooling strategies like orientation, building size, thermal mass, window design and two direct cooling strategies have been investigated in this study. Direct cooling strategies like shading and natural cooling helps in passive cooling. Different desing strategies have different impact on the cooling energy requirement and the study shows that thermo physical property of building materials has the maximum effect on the energy consumption of the building. Each design strategy creates and average of 20% decrease in energy consumption, whereas the thermal conductivity can have as much as 10 times more effect on the energy consumption than other design strategies.

• Journal of Dental Anesthesia and Pain Medicine
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• 제15권1호
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• pp.1-4
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• 2015

In pediatric dentistry, chloral hydrate is habitually selected for sedation of uncooperative children. Although chloral hydrate has been used for decades, various adverse effects are reported and necessity for new alternative drugs has increased. Dexmedetomidine was approved by FDA for sedation at intensive care units (ICU) in 1999. Compared to conventional sedative drugs, dexmedetomidine has not only analgesic and sedative effects but also it barely suppresses the respiratory system. Due to these characteristics, dexmedetomidine is known as safe sedative drug for children and elderly patients. Furthermore, approved by KFDA in 2010 in Korea, the frequency of sedation using dexmedetomidine is increasing. However, due to its intravenous administration method, it was difficult to apply in pediatric dentistry. Recently, intranasal administration method was introduced which might be a new possible alternative of oral sedation. In this study, we compare the mechanisms, pros and cons of chloral hydrate and dexmedetomidine, introducing new possibilities.

• 한국멀티미디어학회논문지
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• 제18권8호
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• pp.980-987
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• 2015

Most of cultural area which people enjoy and consume is kitsch culture, though the culture is barely acknowledged. In this multimedia era, people create, publish and enjoy contents of 'webtoon(web+cartoon)', which is relatively faster and more convenient to enjoy comparing to published cartoon. Contrarily to its physical growth, the webtoon shows difficulty in advancing with other genres, is full of irritative factors and contents, and has tough time to become more sophisticated one. This study derived characteristics of kitsch in webtoon, suggested the way of webtoon as an art by analyzing conditions and usage motivation of webtoon. The conditions of kitsch are uniformity of mass consumption, popular vein, catharsis, vicarious satisfaction, immediate feedback-requiring image flood, and reproduction of techniques. The usage motivations of webtoon are studied as pursuit of information, entertainment, relaxation, socialization, convenience, and effectiveness. Usage motivation factors in webtoon and kitsch culture are almost identical. Contrary to its past of being underestimated and vulgarly considered, kitsch is acknowledged as an 'kitsch art'. By studying the process of becoming an art, the study has its purpose to suggest the experimental and developing way to make webtoon be acknowledged as 'webtoon art'.

• 대한교통학회지
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• 제18권1호
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• pp.27-34
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• 2000

이 연구는 최근 소비자 행동분석에서 많이 사용되고 있는 설문조사에 의한 Stated Preference의 방법론을 채택하여 항공여객수요의 가격탄력성을 분석하였다. 우리나라의 국내선 항공은 항공요금이 지금가지 인가제나 신고제로 규제되어 왔기 때문에 통상의 총량자료에 의한 회귀분석으로는 가격탄력성 도출이 어려우며 특별한 분석방법론을 필요로 한다. 이 연구에서는 항공여객에 대한 설문조사로 항공편과 철도, 버스, 승용차 등 대체교통수단과의 선택 여부에 대한 자료를 입수한 후, SP기법에 따른 Logit model로 분석하여 항공수요의 가격탄력성과 대체교통수단으로의 모드별 쉐어 변환율을 Sample Enumeration 방식에 의해 추정하였다 대체 가격탄력성은 -0.6∼-0.9의 값으로 밝혀졌으며 대체교통수단으로는 주로 철도를 선택하고 일부 버스를 선택하며 승용차는 거의 선택하지 않는 것으로 조사되었다.

• 한국주거학회논문집
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• 제21권2호
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• pp.41-48
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• 2010

This study shows how the water space outside the housing impacts the indoor thermal environment. CFD simulation was used for this experiment to analyze the interior environment focusing on the effect of temperature control and the thermal comfort. A shape of perfect square, which creates the very basic space formation, was used and the simulation was processed looking at the size, distance, and the location of the water space. The results of the experiment are as follows. Firstly, introducing a water space with the same floor area size of the simulation model decreased the indoor temperature by 1 Celsius (3.72%). It was determined the interior environment was considered as a comfort zone when the water space was greater than 70% of the floor area. Secondly, there was not much influence to the level of thermal comfort of the interior environment when the distance to the water space from the housing was greater than 2 meters. Lastly, interpreting the location of water space, the effect of controlling the total areas' temperature was the greatest following with the surrounding of the formation. There barely was any change to the temperature considering the side and the rear of the area.

• 대한가정학회지
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• 제41권5호
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• pp.99-108
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• 2003

The Purpose of. this study was to investigate the relationship between sociocultural attitude toward appearance and appearance-management behavior. The method of the study was survey research by using questionnaires. Subjects were 323 females in their twenties. Statistical analysis methods were frequency, percentage, factor analysis, one-way ANOVA, X²-test, and Duncan's multiple range test. The results of the study were as follows. As for appearance-management behaviors of females in their twenties, they experienced in diet, plastic surgery, skin care, make up, and hair dyeing. There were significant differences in body satisfaction between groups according to body image distortion. Respondents were barely satisfied with their body, and the group with high body image distortion showed low body satisfaction. Sociocultural attitude toward appearance factors was analyzed into 2 factors, iternalization of mass-media and social recognition toward appearance, which respondents considered importantly. A significant difference was found in sociocultural attitude toward appearance and appearance management behavior. The group with positive sociocultural attitude toward appearance was analyzed to show high appearance concern and many experiences of appearance management behaviors.