• 한국가정과학회지
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• 제5권1호
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• pp.48-61
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• 2002

This study was carried out to investigate the effects of four kinds of leavening agents on Jeung-Pyun fermantation. Milk-wine(M), fresh yeast(F), dry yeast(D), instant yeast(I) were used in Jeung-Pyun ingredients. The physicochemical properties, sensory evaluation were examined. The results of this study are summarized as follows: 1. Basic recipes for Jeung-Pyun by preliminary test were developed. 2. Specific volumes and expansion ratio of Jeung-Pyun was higher in the fresh yeast-added sample. 3. The pH of Jeung-Pyun was decreased significantly as the fermentation progressed 4. In the result comparing Jeung-Pyun extracting after 1st fermentation with Jeung-Pyun extracting 2nd fermentation by SEM, the former was widely distributed in stability of bubble and pore than the latter. 5. Standard recipe by Q.D.A. test added four kinds of leavening agents were as follows: (1)Jeung-Pyun added milk wine was 240min for 1st fermentation time, 60min for 2nd fermentation time, 35$^{\circ}C$ for fermentation temperature, 80% for fermentation humidity respectively. (2) Jeung-Pyun added fresh yeast was 90min for 1st fermentation time, 40min for 2nd fermentation time, 35$^{\circ}C$ for fermentation temperature, 80% for fermentation humidity respectively. (3)Jeung-Pyun added dry yeast was 90min for 1st fermentation time, 60min for 2nd fermentation time, 35$^{\circ}C$ for fermentation temperature, 60% for fermentation humidity respectively. (4)Jeung-Pyun added instant yeast was 90min for 1st fermentation time, 40min for 2nd fermentation time, 30$^{\circ}C$ for fermentation temperature, 60% for fermentation humidity respectively. 6.Based on sensory evaluation, Jeung-Pyun added fresh yeast was significantry higher than others in color, sweetness, moistness, softness, and overall quality. There was negative significance between milk wine flavor and astrigentness, and yeast flavor.

• 농업과학연구
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• 제48권1호
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• pp.45-57
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• 2021

This study aimed to determine the effects if ambient temperature (Ta), relative humidity (RH), and temperature-humidity index (THI) on milk production parameters such as milk yield, fat, protein, milk urea nitrogen (MUN), and lactose. A total of fifty (50) mid-lactating Korean Holstein cows (144 - 150 days postpartum) were randomly assigned to two groups in equal numbers (n = 25) according to the type of diet received: conventional feed, a mixture of 56: 44 ratio of roughage and concentrate mix, and organic feed containing 100% organic roughage. Temperature, RH, and THI were recorded daily and averaged monthly. Conventional group showed higher dry matter intake throughout the experiment and thus, showed higher total milk yield and milk composition such as milk fat, protein, and lactose content than organic milk. Milk of the conventional group showed higher polyunsaturated fatty acid concentration. Highest milk yield was observed in September (21.7℃, 82.4%RH) in conventional group (27.69 kg·day^-1) and in June (21.4℃, 72.9%RH) in organic group (14.31 kg·day^-1). In conventional group, milk yield was positively correlated with Ta and THI, and milk protein was negatively correlated with Ta, RH, and THI. In organic feeding, only the MUN among milk composition parameters showed a significant correlation where it showed a negative correlation with Ta, RH, and THI. Conventional feeding showed significantly higher milk yield, fat, protein, and lactose than organic feeding throughout the experiment, although, organic feeding showed to be less likely affected by Ta, RH, and THI than the conventional feeding.

• 한국컴퓨터정보학회논문지
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• 제23권11호
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• pp.143-149
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• 2018

The purpose of this study is to propose a management method to maintain the pleasant indoor air quality of the dental clinic by measuring and analyzing the indoor air quality of the dental clinic. The measurement was conducted in two rooms, a lobby where many residents stay in the reception room for waiting for medical treatment, and a VIP room where treatment activities are mainly performed. Measurement items are Temperature, Humidity, $CO_2$, CO, $NO_2$, $CH_2O$, VOC, $PM_{10}$ and measurement were taken on April 27, 2018. As a result of analyzing the temperature and humidity of the dental clinic, it was analyzed that the average indoor temperature was maintained at $25^{\circ}C$ and the humidity was kept at around 50%, maintaining proper indoor temperature and humidity environment. $CO_2$ was 855ppm in the VIP Room, which satisfied the maintenance standard. In the case of the lobby, it was analyzed to be 1,160ppm, which exceeded the maintenance standard and it is judged that the carbon dioxide generated by the respiration of the people staying in the lobby is the main reason. The mean concentration of formaldehyde in the VIP room was analyzed as $436{\mu}g/m^3$, exceeding the maintenance standard, and $2,100{\mu}g/m^3$ for the VOC exceeded the recommended standard. It was analyzed that the concentration was relatively higher due to the use of disinfectant and other drugs. The mean concentration of PM-10 in the lobby was analyzed as $65{\mu}g/m^3$ and it was analyzed that it satisfied the maintenance standard. To maintain a pleasant indoor air quality in a dental clinic it is necessary to minimize the effects of formaldehyde, VOC, $CO_2$ in the VIP rooms and lobby. For this purpose, the entire ventilation system and air purification system of the dental clinic should be installed. In case of the VIP room, local exhaust ventilation should be installed and workers should wear personal protective equipment.

• 마이크로전자및패키징학회지
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• 제29권2호
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• pp.43-48
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• 2022

인쇄전자소자의 금속배선 적용을 위해 스크린 프린팅 Ag/폴리이미드(polyimide, PI) 사이의 계면접착력을 85℃/85% 상대습도의 고온/고습 처리 시간에 따라 PI 필링을 통한 90° 필 테스트로 평가하였다. 고온/고습 처리 전 필 강도는 약 25.99±1.47 gf/mm이었고, 500시간 동안 고온/고습 처리 후 필 강도는 6.05±0.54 gf/mm까지 지속적으로 감소하였다. 박리 파면에 대해 X-선 광전자 분광법 분석 결과, 이는 Ag/PI 계면으로 수분이 지속적으로 침투하여 계면 근처 PI 일부가 가수분해되어 weak boundary layer를 형성하기 때문이고, 이로 인해 고온/고습 처리 전 Ag/PI 계면 박리모드가 고온/고습 처리 후 계면 근처 PI의 얕은 내부 박리 모드로 변경된 것으로 판단된다.

• International Journal of Industrial Entomology and Biomaterials
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• 제45권1호
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• pp.22-28
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• 2022

Silkworms are very sensitive to changes in temperature and humidity, and unless it is a suitable temperature and humidity to grow, the productivity and quality of silkworms are greatly reduced. Therefore, it is very important to manage temperature and humidity for silkworm feeding facilities. In particular, it is essential to install heating facilities in Asian countries with distinct seasonal changes. During the feeding period, many farms manage the temperature and humidity of feeding facilities by installing and using electric heaters inside the facilities. However, it is very difficult to manage the room temperature stably by the heaters. In addition, unlike the temperature inside the facility, silkworms could undergo severe temperature changes as the inside of the rearing tray could not be warm enough. In this study, in order to improve the previous heating method, the new rearing method that directly heats the bottom of the rearing tray was developed. Compared to the previous room-heating system, the novel heater-installed tray (HIT) system significantly reduced the change in temperature during the experimental period. In addition, the number of days of silkworm growth up to harvest was shortened, which was effective in growth performance, and it was also found that silkworms grew more uniformly in HIT system than in previous system. Moreover, as the heater tubes were installed directly under the rearing tray, it quickly dried mulberry leaves and silkworm feces after feeding, and as a result, the environment in the tray was greatly improved with decrease the labor of breeder. In conclusion, these results suggest that the heater-installed rearing tray method greatly improves silkworm quality, increases weight of silkworms, and final profits compared to the previous room heating system with electric heaters.

• 한국연초학회지
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• 제18권1호
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• pp.66-75
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• 1996

This study was carried out to investigate the effects of high temperature and humidity on the ageing of processed leaf tobacco. Four(1993) or six(1994) grades (Both flued-cured and burley) of processed leaf packed in carton box were stored under the natural and artificial conditions. When the Processed leaf was stored in the controlled mom at 40℃ with 75% R.H.(1993) for 40 days, the leaf pH was decreased. The decreasing rate of leaf pH was similar to that of leaf stored under the natural warehouse condition for 15 months. The degree of lightness and yellowness of leaf also decreased, while the decaying or darkening of the leaf was observed. When the processed leaf was stored in the controlled room at 35℃ with 65% R.H.(1994) for 90 days, the pH of flue-cured was decreased 0.22, which was similar to that of the leaf stored under the natural warehouse condition for 15 months, and the lightness, and redness of the leaf were higher than those of the control. As compared with the leaf stored under the natural condition for 2 years, the smoking quality of leaf stored under this condition was similar or somewhat better. The pH of burley tobacco changed little compared to that of flue-cured during storage in this study.

• 한국환경과학회지
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• 제12권7호
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• pp.697-704
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• 2003

Through data analysis using the meteorological data during 40 years(1961∼2000) for 2 stations(Daegu and Chupungnyong), we studied the present condition and long-term trends in urban climatic environments of Daegu. It was found that there was about 1.5$^{\circ}C$ rise in annual mean temperature of Daegu from 1961 to 2000. On the other hand, that of Chupungnyung was not more than 0.4$^{\circ}C$ for the same period. The regional disparity in temperature changes has been caused by the difference of urban effects on climate between two regions. In particular, the urban warming appears more significant in winter season. There was about 3$^{\circ}C$ rise in annual mean daily minimum temperature of winter season(Dec.∼Feb.) in Daegu. As the result, the number of winter days continuously decreased from 115 days(1961) to 75 days(2000). The long-term trends of relative humidity were also studied to exame the effects of urbanization on climate in Daegu. It was found that there was about 7% decrease in relative humidity of Daegu during past 40 years(1961∼2000). On the other side, the decrease of Chupungnyung was not more than 2% for the same period. The long-term trends of the other climatic factors(fog days, tropical night days, etc) were also studied in this study.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 B
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• pp.750-752
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• 1992

The paper presents the effects of environment on glass-cloth/epoxy composites exposed to humid air were investigated. Tests were performed at temperature 40$^{\circ}C$ and 70$^{\circ}C$ with the materials exposed to humid air at 76% and 90% relative humidity. This investigation surveyed include (a) the moisture absorption and desorption characteristics of single and multi layered composites exposed to steady and to transient ambients, and (b) the resulting changes in tensile strength, dielectric strength, tan $\delta$ and $\varepsilon_{\tau}$ and the effects of environment on these parameters were assessed.

• Journal of Preventive Medicine and Public Health
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• 제31권1호
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• pp.82-90
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• 1998

A large number of studies have indicated associations between particulate air pollution and daily mortality. Daily measurements of total suspended particulates (TSP) by high volume air sampler were matched to daily death counts supplied by the National Statistics Office, Korea. All deaths, except deaths from accidents, occurred at Ulsan from 1 January 1991 to 31 December 1994 were considered in the poisson regression analysis. The multiple regression models were used to investigate a main effects of air particulate pollution controlling for $SO_2$ levels, air temperature, relative humidity, seasonal variation, and calendar year. The results indicated that the effects of TSP, $SO_2$, temperature, and relative humidity were not significantly associated with all cause mortality. It could, however, be emphasized that the size of the parameter estimate of TSP was very similar to that of previous studies. An increase in particulates of $100{\mu}g/m^3$ was associated with a 3% increase in mortality. This relationship was observed at TSP levels well below the current National Ambient Air Quality Standard of $150{\mu}g/m^3$ in Korea as well.

• Journal of Biosystems Engineering
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• 제34권1호
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• pp.30-36
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• 2009

This study was performed to determine the effect of drying conditions on the germination properties of rapeseed after seeds were dried under different drying conditions: $40^{\circ}C$, $50^{\circ}C$, or $60^{\circ}C$ in combination with 30%, 45%, or 60% relative humidity. As analytic results, drying conditions had significant effects (P-value < 0.001) and drying temperature was considered as the main factor on the germination properties of rapeseed. When drying temperature increased or relative humidity decreased, the vigor rate and germination rate decreased, the median germination time increased. The maximum values of vigor rate and germination rate were 90% and 95.44%, and their minimum values were 60.17 and 75%, respectively. To ensure the standard germination rate of 85%. The appropriate drying zone was determined and the drying temperature should be less than $51.0^{\circ}C$, $54.5^{\circ}C$ and $58.7^{\circ}C$ at 30%, 45% and 60% RH, respectively. The values for median germination time varied from 2 to 4 days. The predicted models of germination rate, vigor rate, and median germination time were determined.