• KIEAE Journal
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• v.3 no.2
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• pp.37-44
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• 2003

The aim of this study was to analyze the thermal performance through Test-Cell of TI-wall in domestic climate. This study was carried out as follows: 1) The TI-wall was studied for ability to reduce heat loss through the building envelope and analyzed to TIM properties. 2) Test models of TI-wall were designed through the investigation of previous paper and work, measured for winter and spring, and the thermal effects were analyzed. The type of the TIM used in test model is small-celled(diameter 4mm and thickness 50mm) capillary and cement brick(density $1500kg/m^3$) was used by thermal mass. 3) Test-cell of TI-wall was calibrated from measured data and the dynamic simulation program ESP-r 9.0. In these simulations, the measured climate conditions of TaeJon were used as outdoor conditions, and the simulation model of Test-cell was developed. 4) The sensitivity analysis is executed in various aspects with standard weather files and ESP-r 9.0, and then most suitable system of TI-wall are predicted. Finally, The suitable system of TI-wall was analysed according to sizes of air gap, kinds, thickness, and the surface absorption of therm wall. The result is following. In TI-wall, Concrete is better than cement brick, at that time the surface absorption is 95%, and the most efficient thickness is 250mm. As smaller of a air gap, as reducer of convection heat loss, it is efficient for heating energy. However, ensuring of a air gap at least more than 50mm is desirable for natural ventilation in Summer.

• Journal of the Korean Dietetic Association
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• v.13 no.2
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• pp.194-206
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• 2007

The purpose of this study was to identify dietitians' perception and purchasing pattern of fruits in elementary school lunch program. This study was conducted using mail survey from September 15 to October 30, 2006. Survey questionnaire was developed based on in-depth interview with three school food service dietitians. A total of 100 school food service dietitians in Seoul were participated. Based on the frequency analysis results, over half of respondents(69%) provides fruits every week, and 23% of respondents provides them twice a week. Strawberry, watermelon, apple, and mandarin were identified as the most frequently served fruits in Spring, Summer, Fall, and Winter, respectively. Sixty two percent of respondents indicated they offered imported fruits, such as banana and pineapple, less than 10% of total fruits. Ninety three percent of respondents selected private contract when they purchase fruits, and forty four percent of dietitians decided fruits purchasing procedure by themselves. Respondents addressed "Apples and Pears were appropriate for a dessert." and "Apples and Pears supply nutrition such as calorie and vitamin." as the advantages of offering apples and pears in school lunch menu. They also indicated difficulty in preparation work and many leftovers as the disadvantages of offering apples and pears. When purchasing apples and pears, dietitians considered taste as the first criteria and price as the second. Respondents perceived that elementary school students preferred apples and pears in a neutral level. Respondents also had higher preference for an-sim apples which can be eaten without peeling for school lunch menu and higher intentions to provide in school lunch menu. The survey results also found that respondents' intention to offer apples in school lunch menu was higher than intentions to offer pears. The implications to increase the chance of fruits offering in school lunch menu were discussed.

• Journal of Environmental Science International
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• v.12 no.8
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• pp.853-860
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• 2003

Plants sequester atmospheric CO$_2$, a major agent of climate change, during the growing periods and mitigate its rising accumulation in the atmosphere. Pinus densiflora and Quercus mongolica are the native tree species dominant in the temperate forests of Korea. This study quantified the annual CO$_2$ uptake by the two species at forest sites in Chuncheon in the middle of the country. The quantification was based on seasonal measurements of CO$_2$ exchange rates under natural conditions by an infrared gas analyzer over the growing season (1999). The monthly CO$_2$ uptake per unit leaf area ranged from 1.6-6.7 mg/d㎡/h for P. densiflora and from 3.7-8.9 mg/d㎡/h for Q. mongolica, with a maximum in mid-summer. An equation for each species was generated to estimate easily the annual CO$_2$ uptake by total leaf area per tree, which subtracted the CO$_2$ release (i.e. respiration) by leaves and woody organs from the gross CO$_2$ uptake (diurnal uptake and release by leaves). Annual CO$_2$ release by leaves and woody organs accounted for 58-73％ of the gross CO$_2$ uptake across tree specimens. Annual CO$_2$ uptake per tree increased with increasing dbh (stem diameter at breast height) for the study diameter range, and was greater for Q. mongolica than for P. densiflora in the same dbh sizes. This was mainly associated with a greater total leaf area in the former. For example, the annual CO$_2$ uptake by one tree with dbh of 25 cm was 35.6 kg/yr for P. densiflora and 47.9 kg/yr for Q. mongolica. The results from this study can be applied to evaluate an atmospheric CO$_2$ reduction of woody plants by forest type and age class.

• Journal of the Korean earth science society
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• v.33 no.5
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• pp.377-394
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• 2012

To elucidate the mechanism associated with the development of heavy precipitation system, a field experiment was carried out in Jejudo (or Jeju Island) and Marado, Korea from 22 June to 12 July 2006. The synoptic atmospheric conditions were analyzed using the National Centers for Environmental Prediction-National Center for Atmospheric Research's (NCEP/NCAR) reanalyzed data, weather maps, and sounding data. The kinematic characteristics of each precipitation system were investigated by dual Doppler radar analysis. During the field experiment, data of four precipitation events with more than 20 mm rainfall were collected. In F case (frontal precipitation), a typical Changma front was dominant and the observation field was fully saturated. However there was no convective instability near the surface. LF case (low pressure accompanied with Changma front) showed strong convective instability near the surface, while a strong convergence corresponded to the low pressure from China accompanied with Changma front. In FT case (Changma front indirectly influenced by typhoon), the presence of a convective instability indicated the transport of near surface, strong additional moisture from the typhoon 'EWINIAR'. The convergence wind field was ground to be located at a low level. The convective instability was not significant in T case (precipitation of the typhoon 'EWINIAR'), since the typhoon passed through Jejudo and the Changma front was disappeared toward the northeastern region of the Korean peninsula. The kinematic (convergence and divergence) characteristics of wind fields, convective instability, and additional moisture inflow played important roles in the formation and development of heavy precipitation.

• Journal of Family Resource Management and Policy Review
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• v.10 no.1
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• pp.53-66
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• 2006

This study was designed to get basic informations for the purpose of making healthy leisure environment of college students, and which will improve the satisfaction of their school life. Five hundreds of college students in Daegu and Gyeongbuk area were questioned by, our questionnaire during April, 2005. The data of 405 students (165 men, 240 women) Were analyzed by SPSS WIN 12.0 program. The data of 210 were from Daegu and 195 were from Gyeongbuk area, The results are as follows, First, $80\%$ of those questioned spend their leisure time doing some activities and the satisfaction degree was medium... They get the informations about leisure mainly through internet and the purpose of their leisure activities, were, to get rid of stress. Second; It was shown that their main leisure activities were doing internet, meeting friends, and listening music on weekdays, meeting friends, watching movie and doing internet on weekend. The major activities of the students during vocation were meeting friends, doing internet, and watching TV. Third, the students are concern about their leisure life, and they think that leisure life make improve the quality of life. The last, there is a correlation between quite activities such as watching TV, and dynamic activities such as a mountain-climbing leisure life satisfaction on weekdays. On weekend, however, there is a correlation between dynamic activities such as sports and the leisure life satisfaction. Moreover, on summer (winter) break personal activities such as religious activities and the leisure satisfaction.

• KIEAE Journal
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• v.17 no.4
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• pp.67-74
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• 2017

Purpose: As the recent climate environment changes so rapidly, environmental problems such as hot weather and fine dust have occurred, and interest in environmental policies and technology development is increasing in countries around the world. Similarly in the Architecture, researches to reduce greenhouse gas emissions and to reduce energy application are actively conducted. Looking at previous studies, it is analyzed that the electric VRF is more energy efficient than the gas engine VRF. However, energy costs have changed due to recent price hikes and discounts on gas charges due to high electricity consumption in summer. Method: In this study, the actual building of Gas Engine VRF system was modeled using SketchUp program, and EnergyPlus was used to simulate actual building. Also, Electric VRF system was simulated, and compared with Gas Engine VRF system. Result: The total secondary energy requirement of Electric VRF system was 19.6% less than that of the Gas Engine VRF system, But when analyzing with primary energy requirement, EHP used 15.8% more energy. CO2 emissions were also estimated to be 16.9% more EHP. Energy costs were 14.8% more in Electric VRF systems, because their electricity charges are 0.6 to 160% more expensive than gas charges.

• Journal of The Korean Association of Information Education
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• v.20 no.2
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• pp.171-178
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• 2016

I will introduce robotics education, Novel Engineering, STOMP have hosted in CEEO at Tufts University. CEEO is a leading center for Robotics Education in all over the USA. So far lots of universities and centers have adopted these programs. CEEO have hosted many workshops for students and teachers every summer vacation. And Simple Robotics course is required for every Engineering department freshmen. Novel Engineering(NE) is not familiar to us. I think that NE will be a good tool for integrating reading literacy and engineering. When teachers design a engineering class, members of STOMP help teachers achieve the goals of class. Software Education has been widely spreaded for last several years in South Korea. If our country adopts these programs government-widely. I think that It will be able to contribute to foster SW-talented persons.

• Journal of the Korea Institute of Building Construction
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• v.14 no.6
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• pp.583-590
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• 2014

The purpose of this study is to analyze and compare the life cycle cost of window glass with insulation film and regular glass, to verify an economical window construction method. As an approach method, the thermal performance data of each type of glass was measured using Window 6.3 and ECO2-OD Simulation Program, applied it to the case building to calculate the air conditioning and heating maintenance costs and LCC, and compared the economic feasibility. As a result, installing an additional insulation film prevents the solar heat penetration in the summer, so it reduces the cooling cost, on the other hand, it increased heating cost in winter. From the life cycle cost perspective, the effect of cooling cost reduction does not counterbalance the increase in heating cost and the additional cost from film installation and repair; therefore, the installation of insulation film may not be a proper method.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.18 no.1
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• pp.72-79
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• 2008

This study was surveyed to assess the status of safety accidents occurred in work-places and prepare the fundamental data and prevent the safety accidents. The authors reviewed and analysed the charts of accident cases treated at a primary care clinic in A city from January 1991 to December 2006. The data were classified according to the USA Standards Institute and International Labour Organization method. We analyzed the data using SPSS program. The results were as follows : 1. The total cases of accidents were 455 for 8 years. 2. Accidents were mostly common in the workers who are in thirties and forties age(84.4%). 3. As season variation, spring and summer were common than others, but there was no statistical significance on season, month and weekday. 4. The most frequent injured part of the body were hand and finger, which was 36.0% among total cases. 5. According to the accidents type, cases of caught in, under or between were most frequently observed as 53.9% of the total cases. 6. The most common source of injuries was power machine(50.5%). 7. According to the unsafe acts, cases of carelessness and unsafe information were most frequently observed as 71.2% of the total cases. 8. Admission rate(5.5%) and official report rate(2.2%) were very low rate. As above results, the authors recommend to prepare the systemic control programs on environmental and human factors of safety accidents such as improving the working conditions, working facilities, working methods and safety education, and control of working time for working day.

• Journal of Korean Society of Forest Science
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• v.101 no.4
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• pp.558-566
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• 2012

This study was conducted to offer preliminary data for a natural restoration by the actual condition survey of quarries after extracting rock materials. The mountain restoration area according to a farming and fishing village organize project was restored by green landscape after quarry. However, planting tree species were died due to poor maintenance and administration after restoration works and surface soil loss and erosion occurred during a summer rainfall season because of poor slope greening. It will be needed to review restoration constructions to establish a natural friendly and flawless construction through the selection of optimum restoration works and the examination of soil and geological characteristics. In addition, it is necessary to apply cost-reducing program of restoration constructions. Quarry areas could be restored by the selection of simple and optimum construction works because the most areas were dominant in earth-sand rocks, soft-rocks, and weather-rocks. In addition, the restoration construction project should be examined thoroughly by restoration specialists during green restoration planning and review processes.