• Korean Journal of Environment and Ecology
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• v.29 no.6
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• pp.936-946
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• 2015

This study is aimed to analyze the reduction performance of building energy consumption according to planting base types of panel-type green walls which can be applied to existing buildings. The performance was compared to the general performance of green walls that have demonstrated effects of improving the thermal environment and reducing building energy consumption in urban areas. The number of planting base types was 4 in total, and simulations were conducted to analyze the thermal conductivity, thermal transmittance, and overall building energy consumption rate of each planting base type. The highest thermal conductivity by the planting base type was Case C (0.053W/mK), followed by Case B (0.1W/mK) and Case D (0.17W/mK). According to the results of energy simulation, the most significant reduction of cooling peak load per unit area was Case C (1.19%), followed by Case B (1.14%) and Case D (1.01%) when compared to Case A to which green wall was not applied; and the most significant reduction of heating peak load per unit area was estimated to be Case C (2.38%), followed by Case B (1.82%) and case D (1.50%) when compared to Case A. The amount of yearly cooling and heating energy use per unit area showed 3.04~3.22% of reduction rate. The amount of the 1st energy use showed 5,844 kWh/yr of decrease on average for other types when compared to Case A. The amount of yearly $CO_2$ emission showed 996kg of decrease on average when compared to Case A to which the green wall was not applied. According to the results of energy performance evaluation by planting location, the most efficient energy performance was eastward followed by westward, southward and northward. According to the results of energy performance evaluation by planting location by green wall ratio, it was found that as the ratio of green wall increased, the energy performance displayed better results, showing approx. double reduction rate in energy consumption at 100% of green wall ratio than the reduction rate at 20% to 80% of green wall ratio.

• Journal of Bio-Environment Control
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• v.25 no.2
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• pp.123-132
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• 2016

The importance of energy saving technology for managing greenhouse was recently highlighted. For practical use of energy in greenhouse, it is necessary to simulate energy flow precisely and estimate heating/cooling loads of greenhouse. So the main purpose of this study was to develope and to validate greenhouse energy model and to estimate annual/maximum energy loads using Building Energy Simulation (BES). Field experiments were carried out in a multi-span plastic-film greenhouse in Jeju Island ($33.2^{\circ}N$, $126.3^{\circ}E$) for 2 months. To develop energy model of the greenhouse, a set of sensors was used to measure the greenhouse microclimate such as air temperature, humidity, leaf temperature, solar radiation, carbon dioxide concentration and so on. Moreover, characteristic length of plant leaf, leaf area index and diffuse non-interceptance were utilized to calculate sensible and latent heat exchange of plant. The internal temperature of greenhouse was compared to validate the greenhouse energy model. Developed model provided a good estimation for the internal temperature throughout the experiments period (coefficients of determination > 0.85, index of agreement > 0.92). After the model validation, we used last 10 years weather data to calculate energy loads of greenhouse according to growth stage of greenhouse crop. The tendency of heating/cooling loads change was depends on external weather condition and optimal temperature for growing crops at each stage. In addition, maximum heating/cooling loads of reference greenhouse were estimated to 644,014 and $756,456kJ{\cdot}hr^{-1}$, respectively.

• Journal of the Korea Institute of Building Construction
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• v.11 no.5
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• pp.435-441
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• 2011

The life cycle assessment on greenhouse gas emission of reinforced concrete buildings shows that more than 70 percent of greenhouse gas that is discharged by a building is discharged in the building maintenance stage, including cooling and heating. To reduce the greenhouse gas emission, maintenance planning to minimize the energy consumption is necessary in the design stage. In this paper, two heat storage rooms are tested to save the air cooling energy of the buildings. The specimens are essentially identical, except that chamber A contained paraffin sheets as the finishing material, while the other, chamber B, served as a control. The test results show that chamber A with the paraffin sheets exhibited less temperature change than chamber B without the sheets when temperature was increased outside of the specimens. The heating energy was probably consumed in the phase change of the paraffin sheets, which can be useful for reducing energy consumption related to air cooling during the summer.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.7
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• pp.1032-1042
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• 2011

The purpose of this study was to examine the attitudes and satisfaction level towards military foodservices as well as suggest effective ways to increase foodservice quality. A questionnaire survey was administered to 413 subjects, which included 400 soldiers and 13 foodservice managers. The survey period was from August 6 to August 25, 2008. The collected data were statistically treated using SPSS V12.0. Most of the investigated soldiers were 20~25 years old. The foodservice managers were male general officials and the majority of them had no prior food service training. None of the foodservice managers had a dietician certificate. Menu was planned through a local foodservice conference, and most food materials were delivered in the form of center-type and military unit-type. Deficiency and deterioration of food service facilities (28.6%) as well as deficiency in the number of cooking personnel (14.3%) increased the difficulty of operational management. Soldiers expressed a desire for increases in Western (25.7%) and Korean traditional foods (21.5%), which meant menu diversity. To increase the quality of military foodservices, taste of food (40.6%), increased portion size (30.4%), and improvement in hygienic conditions (13.6%) were demanded by the soldiers. Food taste (30.8%), improvement in hygienic conditions (23.1%), and better job management were all demanded by the foodservice managers. After factor analysis, quality attributes were rearranged into five dimensions, including facilities, food, menu, service, and sanitation most attributes were over 4 points out of 5 total in importance, but only 3 points in performance. The importance score was higher than the performance score. Soldiers' overall satisfaction level was on average 3.43 points out of 5 points.