• Journal of Advanced Marine Engineering and Technology
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• v.15 no.5
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• pp.38-46
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• 1991

In the design of an electric power plant, the capacity to meet the peak load demand is one of the important factors to be considered. This peak load usually occurs when the most of the cooling air-conditioning systems are being operated during daytime in summer season. Therefore, it is necessary to construct an additional electric power plant and to develop the new air-conditioning system for relieving the peak load. This paper analysed the performance characteristics of this experimental regenerative ice energy system by means of a bundle of the heat-pipes. And the result of this analysis was applied to the simulation of an air-conditioning system model. Also, an operation program of moisture air was made according to air load and in order to computerize the air-conditioning system a CAD program was developed by the properties of moisture air.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.9
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• pp.1359-1363
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• 2017

In this study, the Relux program was simulated for optimum conditions of daylight and artificial light sources(LED) in the glass greenhouse. From the results of daylight simulation, the optimum design conditions for the glass greenhouse were established which were 90[o] installation angle and higher transmittance. In this case of growing lettuce in the glass greenhouse, the control method of the only artificial light source was compared that of daylight and LED. The result of illumination simulation produced a power consumption effect of 37.2[%] in the summer and 51.9[%] in the winter, respectively. From this results, we propose to suggest that we grow the lettuce in the energy saving glass greenhouse.

• Journal of Environmental Science International
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• v.16 no.5
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• pp.603-610
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• 2007

Recent urban sprawl has destroyed various kinds of green space in tile city. It has affected duality of people's life in the city, as well as urban ecosystem. Recent study shows the possibilities of roofs as green spaces in urban central site where the land costs are generally high. This research focuses on Jung-Gu district in Daegu Metropolitan city as a study area and calculates possible area of green roof using 2002 Autocad program based on aerial photographs and land registration maps. And the purpose of this research is to analyze environmental and economic effects of green roof. The environmental effects are as follows. It is expected that $91,106m^2$ green spaces, 12.13 % of study site, will be added if green roof is performed in the study site. It is assumed that the expanded areas could reduce the highest temperature to $0.5-1.0^{\circ}C$ during the summer in terms of environmental effect. And the following shows the economic effects. If green roof and greening urban central site are created as a same size of $91,106m^2$, it will be expected that the costs of green roof will be much more in-expensive than about 98 billions won. It will be also found that the expense of cooling energy can be saved out about 8 millions won per day in summer, if grass planting is accomplished on the possible areas of green roof in the study site. Therefore, it is desirable to take legal supports such as enacting regulations to activate green roof for more environmental and economic effects. For instance, green roof for public institutions, school and model area selection are desirable method to publicize the effect of greening program for citizen's participation.

• Environmental and Resource Economics Review
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• v.17 no.2
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• pp.213-233
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• 2008

In this paper, we estimate the effects of the two most important means of summer time demand side management in Korean power market: adjustment of vacation or repair timing and the voluntary saving program. We use regression analyses to estimate how effective these two programs are in reducing the peak time demand during the summer. Our results show that adjustment of vacation or repair timing actually reduces the daily peak demand by 0.53 kWh per one kWh reported reduction calculated from the agreements between Kepco and the users. The voluntary saving program reduces the daily peak by 0.57 kWh per one kWh reported reduction calculated from the agreements between Kepco and the users. However, when we include these two effects in the same regression model, their respective estimated effects become much weaker.

• The Korean Journal of Ecology
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• v.24 no.4
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• pp.233-237
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• 2001

Changes of the oribatid mite species composition during the litter decomposition was investigated in the north-facing and south-facing slopes with different lower vegetation (annual herbaceous plants in north and perennial Sasa in south) in the altitude 1,000 m of Mt. Jumbong, a nature reserve area in Korea, from August 1994 to September 1995. Total 58 species of oribatid mites were collected. The values of O1son's negative exponential index (k) were -0.56 in the south-facing slope and -0.49 in the north-facing slope, but there was no significant difference between them. The decomposition rate of litter increased rapidly until Oct. 1994, and decreased thereafter. Intensive settlement of the forest litter by oribatid mites was recorded in the autumn periods and it decreased in the next spring and summer. Species diversity index (H'), and species evenness (J') ranged from 1.74 to 2.69, and from 0.57 to 0.93, respectively, and the values were lowest in spring. In the successive periods of growing season, there followed great changes in the structure of species dominance. Heminothrus minor was one of the most dominant species in autumn in the first year when litter were placed, but was never recovered next seasons. In contrast, Platynothrus yamasakii was also dominant in the first autumn, then decreased very low in numbers in next spring and summer, but regained its number in autumn. On the other hand, an increase of the number during these periods was observed by Epidamaeus sp.2. Ceratopia bipilis and Epidamaeus sp.1 were abundant both in the north-and south-facing slopes. Trichogalumna nipponica was only found in the south-facing slope, and Nanhermannia elegantula was only found in the north-facing slope.

• Korean Journal of Community Nutrition
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• v.13 no.5
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• pp.620-629
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• 2008

The purpose of this study was to assess dietary habits and seasonal variation and diversity of food intakes of elderly women living alone as compared to those of elderly women living with family in a rural area. Forty nine elderly women living alone and forty one elderly women living with family who reside in Goryeong-gun, Gyeongbuk, were interviewed using questionnaires in summer 2005, and their food intakes were assessed secondly in winter and thirdly in spring 2006. The average ages were 74.7 years for elderly living alone and 72.8 years for elderly living with family. Tooth status and bone fracture experience were similar between the groups. The prevalence of musculoskeletal disease was 61.2% and that of circulatory disease was 32.7% of the subjects. Average of total score of mental depression of the subjects was 5.94 out of 12 points, and it was not significantly different between the two groups. Skipping meals was more frequent and mealtime was more irregular in the elderly women living alone as compared with the elderly women living with family. Consumption of dietary supplements was also less in the elderly women living alone. Food intakes by the elderly women living alone tended to be lower than those by the elderly women living with family. Dietary diversity score was significantly lower with the elderly women living alone as compared with the elderly women living with family only in summer (p < 0.01). Percentages of the subjects who have taken meat group and vegetable group were significantly lower in the elderly living alone compared with the elderly living with family during summer. Therefore, it is necessary to develop food assistance or supporting program suited for the season within a community for elderly women living alone.

• Journal of the Korean Institute of Landscape Architecture
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• v.29 no.4
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• pp.91-99
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• 2001

This study was carried out to investigate the effects of mowing height, rolling, N-fertilizing, and season on green speed(i.e., ball-roll distance) for developing and implementing a program of increasing green speed in Korean golf courses. Data were subjected to multi-regression analysis using SPSSWIN(Statistical Package for the Social Science), which collected from Yong-Pyong golf course greens selected to investigate. The results was as follows. 1) The multi-regression analysis of mowing height, rolling times, and N-fertilizer application rates on spring green speed was as follows; $Y_1$(spring green speed)=4.287+0.155X$_1$(rolling times)-0.131X$_2$(the amount of N-fertilizing)-0.251X$_3$(mowing height). 2) The multi-regression analysis of mowing height, rolling times, and N-fertilizer application rates on summer green speed was as follows; $Y_2$(summer green speed)=4.833-0.423X$_3$(mowing height)+0.146X$_1$(rolling times)-0.107X$_2$(the amount of N-fertilizing). 3) The multi-regression analysis of mowing height, rolling times, and N-fertilizer application rates on fall green speed was as follows; $Y_3$(fall green speed)=4.651-0.383X$_3$(mowing height)+0.142X$_1$(rolling times)-0.103X$_2$(the amount of N-fertilizing). 4) As mowing height was lowered by 1mm, green speed increased by 0.251~0.423m. As rolling times increased by 1(one), green speed increased by0.142~0.15m. As the amount of N-fertilizing increased by 1g/$m^2$, green speed decreased by 0.103~0.131m. The season also affected green speed. In comparison with spring green speed, summer green speed decreased by 0.145m and fall green speed decreased by 0.144m.

• Korean Journal of Remote Sensing
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• v.14 no.1
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• pp.1-16
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• 1998

Microwave brightness temperature data measured from the Special Sensor Microwave/Imager (SSM/I) aboard Defense Meteorological Satellite Program (DMSP) satellite are used to investigate the characteristics of hydrological features of the East Asian summer monsoon during 1994 and 1995. The analyzed parameters include total columnar water vapor, cloud liquid water, and rain rate. These are estimated from SSM/I brightness temperature data for the two summer seasons (June, July, August) of 1994 and 1995 over the Asian monsoon region (0$^{\circ}$-60$^{\circ}$N, 45$^{\circ}$-180$^{\circ}$E). Results indicate that there are periodic westward movement of dry air over the 20$^{\circ}$-30$^{\circ}$N latitudinal belt with about 20-30 day period. Considering that the location of the North Pacific high is closely linked to the evolution of the monsoon activities over East Asia, the westward expansion of the North Pacific high may be the one important element modulating the monsoon intensity.

• Journal of the Korean Society of Costume
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• v.58 no.10
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• pp.37-51
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• 2008

The purpose of this study is according to four Seasonal Color system, the researcher analyzed the Korean Personal color and investigated abstract color preferences and the fashion color preferences to support the Korean color preferences and the rotor recognition trend. The study was conducted according to the following procedures: 144 women from 20s to 50s were selected as participants of the survey and the interview. The fashion color preferences and the personal body color was analyzed by the questionnaire and the interview. The data were analyzed by SPSS 12.0 program. As a way of analysis, crosstabs analysis, correlation analysis, t-test, ANOVA and regression analysis were used. As a results, in the Personal color type of Korean women, it is distributed in the order of spring, summer, winter and autumn. In addition, Light image is highly distributed in the Personal color image. People preferred summer color group in the general color preference and the cosmetic color preference and they preferred winter color type in the clothes color and the suitable color for themselves. In the color recognition, as the color interest increases, the coincidence between suitable color and favorite color increased. The recognition of suitable color, the consideration of color in purchasing and the interest of outward appearances were highly showed.

• Journal of Environmental Health Sciences
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• v.29 no.1
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• pp.8-15
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• 2003

In this study, chlorine dose at water storage tank was predicted to meet the recommended guideline for free chlorine residual in drinking water distribution system, using EPANET which is a computer program that performs extended Period simulation of hydraulic and water quality behavior within pressurized pipe networks. The results may be summarized as follows. The decay of chlorine residual by season varied considerably in the following order; in summer ($25^{\circ}C$) > spring and fall (15$^{\circ}C$) > winter (5$^{\circ}C$). For re-chlorination at water storage tank by season, season-varying chlorine dose was required at its maximum of 1.00 mg/l in summer and minimum of 0.40 mg/l in winter as free chlorine residual. The decay of chlorine residual through out the networks increased with water age spent by a parcel of water in the network except for some points with low water demand. In conclusion, the season-varying chlorine dose as well as the monitoring of water quality parameters at the some points which showed high decay of chlorine residual may be necessary to deliver the safe drinking water.