• Wind and Structures
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• v.13 no.6
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• pp.519-528
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• 2010

A meteorological model, RAMS, and a commercial computational fluid dynamics (CFD) model, FLUENT are combined as a one-way off-line nested modeling system, namely, RAMS/FLUENT system. The system is experimentally applied in the wind simulation over a complex terrain, with which numerical simulations of wind field over Foyeding weather station located in the northwest mountainous area of Beijing metropolis are performed. The results show that the method of combining a meteorological model and a CFD model as a modeling system is reasonable. In RAMS/FLUENT system, more realistic boundary conditions are provided for FLUENT rather than idealized vertical wind profiles, and the finite volume method (FVM) of FLUENT ensures the capability of the modeling system on describing complex terrain in the simulation. Thus, RAMS/FLUENT can provide fine-scale realistic wind data over complex terrains.

• Fashion & Textile Research Journal
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• v.13 no.5
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• pp.752-758
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• 2011

In this paper, experiments to develop working clothes and evaluated, including the current and material-improved working clothes in relation to physiological functionality measurement. Experiments were conducted on subjects after wearing working clothes in an climate chamber, and the thermo-physiological response, such as human body temperature, micro-climate within the clothes, blood pressure, heart rate were measured. In this manner, the physiological functionality of improved working clothes was compared with that of current working clothes and evaluated. The summary of obtained results is as follows: For physiological functionality evaluation through material-improved working clothes, P working clothes showed significantly lower rectal temperature than C working clothes. For mean skin temperature, P's skin temperature was significantly higher than C's in the second half of the experiment. P working clothes's temperature around the thighs in Micro climate was significantly lower than that of the C working clothes. Also, humidity within the clothes showed similar trends. During the exercise period, C working clothes showed higher blood pressure than P, but P showed higher heart rates than C. Also, the oxygen uptake amount was higher in C than P during the exercise period, it explains that the energy consumption amount of P working clothes was smaller than that of C working clothes. Of the subjective evaluation, for temperature sensation, workers wearing P working clothes felt cooler. For humidity, C working clothes showed more humidity. For comfort, P working clothes were better, and for sense of fatigue, workers felt less tired wearing P working clothes. From results above, we can see that physiological functionality improved in the material-improved working clothes in the working clothes for construction site workers. The improvement of working clothes through functionality improvements not only will provide personal pleasantness to constriction site workers, but will also generate efficiency and productivity improvements at construction sites. All in all, the continuous study of functionality improvements in working clothes taking into consideration the human body's physiological responses is required.

• Fashion & Textile Research Journal
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• v.2 no.5
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• pp.416-422
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• 2000

In this study, to find out the physiological reaction of the human body and the sensation of comfort when people are wearing sportswear which is made of waterproof breathable fabrics under general environmental conditions (temperature : $20{\pm}1^{\circ}C$, humidity : $60{\pm}5%RH$, air current : 0.1 m/sec) and rainy environmental conditions (temperature : $20{\pm}1^{\circ}C$, humidity : $60{\pm}5%RH$, air current : 0.1 m/sec, rainfall : 250 1/hr), we made an experiment with sportswear in an artificial climate chamber and studied the thermal physiological response and subjective sensation. Mean skin temperature of the subjects was low and had a big range of fluctuation in rainy environmental conditions of two condition. Temperature started to increase at the beginning of the exercise, reached the maximum at the 2nd level of the exercise and then started to decline. Rectal temperature showed a slighter increase and bigger range of fluctuation in general conditions than in rainy conditions. Except clothing micro climate in rainy conditions, temperature and humidity and their range of fluctuation around back were higher than those around chest. Humidity was high and had wide range of fluctuation in general conditions. Heart rate was 4.4 beats/min higher in general conditions. In subjective test on rainy conditions, the feeling of discomfort increased due to the raindrops fallen on the skin. Unlike that in general conditions, cold sensation increased and humidity sensation reached to the peak after the exercise. In wearing sportswear made of shape memory breathable waterproof fabric, controlling function over a small amount of heat and water was distinctive while it turned out to be not so comfortable over a large amount of heat and water. Through this, the limitation of shape memory breathable waterproof fabric was recognised.

• Journal of the Korean Solar Energy Society
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• v.25 no.4
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• pp.111-118
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• 2005

The purpose of this study is to address the progress of the heat island phenomenon and the scheme to decrease in heat island phenomenon through analysis of micro-climates according to land use and make a plan to construct wind ways. The result is: 1) Analysis of temperature and humidity at 6 spots for 24 hours showed that heat island phenomenon was considerably intense around center road of Gwangju and can be mild through making lakes and green zones. 2) Analysis of the direction and velocity of the wind at 2 spots for 24 hours showed that the direction of the wind at the center of Gwangju was SSW(South-South-West) and average velocity of the it was $1.2{\sim}1.5\;m/s$. To make the inflow of the low-temperature air current from Mt. Mudeung into the city through Gwangju river, efficient management of Gwangju riverside parks should be considered for Gwangju river itself to be wind way. 3) Analysis of mobile temperature measurement on 3 courses for 24 hours showed that the low-temperature air current of Mt. Mudeung and a micro-climate of Gwangju river can lighten thermal storage phenomena of the city in that the temperature was lowest at Gwangju riverside. These outcome is from a day term measurement. So, to figure out accurate condition of heat island phenomenon in Gwangju City, it is needed to have long term measurements and accumulation of those information.

• Journal of Korean Society of Forest Science
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• v.98 no.1
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• pp.33-48
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• 2009

Forests store carbon dioxide ($CO_2$), one of the major factors of global warming, in vegetation and soils through photosynthesis process. In addition, woods deposit $CO_2$ for a long term until the harvested wood is decomposed or burned, and deforested areas could be expanded the carbon sinks through reforestation. Forests are a lso able to decrease temperature through transpiration and contribute to control the micro climate in global climate systems. Consequently, forests are considered as one of major sinks of greenhouse gases for mitigating global warming. It is very important to develop a Korea specific forest carbon flux model for preparing adaptation measures to climate change. In this study, we compared the climate change impact models in forests developed in foreign countries and analyzed the applicability of the models to Korean forest. Also we selected models applicable to Korean forest and suggested approaches for developing Korean specific model.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.7
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• pp.1032-1038
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• 2017

Recently, regulation on carbon emissions has been strengthened according to the new climate change convention (COP21) held in Paris, and then Korea has decided to reduce CO2 emissions by 37% until 2030. As one of countermeasures, the government has energetically performed demonstration projects of island micro-grid including solar power, wind power and energy storage system. However, in order to smoothly introduce island micro-grid, it is a critical issue to carry out the economic evaluation for power utility aspect and independent power producer aspect. Therefore, this paper proposes economic evaluation algorithms of island micro-grid which are based on the present worth method, considering cost and benefit factors in the aspect of both sides. Firstly, in case of power utility this paper proposes algorithm to estimate a period of return on investment according to the introduction capacity of distributed generators replacing diesel generator. And also, in case of independent power producer, this paper proposes evaluation algorithm to estimate weighting factor of SMP and benefit rate based on break-even point related with cost and benefit. From a case study result on real island micro-grid model, it is confirmed that proposed algorithms are useful and practical for the economic evaluation of island micro-grid.

• KIEAE Journal
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• v.15 no.1
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• pp.89-95
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• 2015

The centralized power supply system and rainwater treatment system, which are major infrastructure in modern cities, are showing their limitations in accommodating environment load due to climate changes that has aggravated recently. As a result, complex issues such as shortage of reserve power and urban flooding have emerged. As a single solution, decentralized systems such as a model integrating photovoltaic system and rooftop greening system are suggested. When these two systems are integrated and applied together, the synergy effect is expected as the rooftop greening has an effect of preventing urban flooding by controlling peak outflow and also reduces ambient temperature and thus the surface temperature of solar cells is lowered and power generation efficiency is improved. This study aims to compare and analyze the monitoring results of four algorithms that define correlations between micro-climate variables around rooftop greening and the surface temperature of solar cells and generate their significance. By doing so, this study seeks to present an effective algorithm that can estimate the surface temperature of solar cell that has direct impact on the efficiency of photovoltaic power generation by observing climate variables.

• KIEAE Journal
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• v.6 no.1
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• pp.57-62
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• 2006

Korean Traditional houses has been evolved and developed in many years, adopting the natural environment to control exterior conditions. These control method are various passive system of using natural materials, considering micro climate, building lay out, and these system are more natural and ecological to make the comfortable indoor climate than active systems of the present houses. This study aims to analyzed control performance of outdoor environment of five Korean traditional houses during the summer and winter. These houses are varied with lay out and floor plan to reflect the way of control for environmental condition, surveyed the reverberation time and sound level difference between rooms of the main living room and other main floored room, master room and kitchen. Especially air temperature and humidity have been measured simultaneously in each rooms to compare with outdoor condition. As a result, the variation of air temperature and humidity of most rooms are considerably static while condition of outdoors are much varied, it is showed that indoor climate has been controled with traditional soiled walls.

• Transactions of the Korean hydrogen and new energy society
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• v.19 no.2
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• pp.171-181
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• 2008

There are several methods for the gas hydrate production such as spraying water with countercurrent gas flow, stirring water-gas mixture, and flowing water with micro-bubble, etc. These days it has been widely studied for the gas hydrate production method, having low energy consumption and high efficiency. In this paper, patents in the gas hydrate production method were gathered and analyzed. The search range was limited to the open patents of USA, European Union (EP), Japan (JP), and Korea (KR) from 1991 to 2007. Patents were gathered by using keywords searching and filtered by crucial criteria. The trends of the patents were analyzed by the years, countries, companies, and technologies.

• Journal of the Korean housing association
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• v.11 no.3
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• pp.137-144
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• 2000

The purpose of this study is to examine the climate characteristics of Haheo in order to find ecological design of a traditional village and residence. In this study, the weather data during sixteen month from May 1998 to August 1999 was measured and analyzed. The results of this study were as follows; 1) In winter, the west wind was dominant at the 60% of rate during the day. The rate of west wind decreased to 30% at night, while the rate of south wind and south-east wind increased to 40%. 2) The relative humidity was higher than 90% at morning because of a fog in summer. 3) In summer, there were many days that the air temperature rose over $30^{\cire}C$ in the daytime, but the air temperature fell about $20^{\cire}C$ at night.