• Mass Spectrometry Letters
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• v.14 no.4
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• pp.147-152
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• 2023

The increasing demand for two-dimensional imaging analysis using optical or electronic microscopic techniques has led to an increase in the use of simple one-dimensional and two-dimensional mass spectrometry imaging. Among these imaging methods, secondary-ion mass spectrometry (SIMS) has the best spatial resolution using a primary ion beam with a relatively insignificant beam diameter. Until recently, SIMS, which uses high-energy primary ion beams, has not been used to analyze molecules. However, owing to the development of cluster ion beams, it has been actively used to analyze various organic molecules from the surface. Researchers and commercial SIMS companies are developing cluster ion beams to analyze biological samples, including amino acids, peptides, and proteins. In this study, a water droplet ion beam for surface analysis was realized. Water droplets ions were generated via electrospraying in a vacuum without desolvation. The generated ions were accelerated at an energy of 10 keV and collided with the target sample, and secondary ion mass spectra were obtained for the generated ions using ToF-SIMS. Thus, the proposed water droplet ion-beam device showed potential applicability as a primary ion beam in SIMS.

• Bulletin of the Korean Chemical Society
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• v.20 no.10
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• pp.1136-1144
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• 1999

The collision-induced reaction of gas-phase atomic hydrogen with hydrogen atoms chemisorbed on a silicon (001)-(2×1) surface is studied by use of the classical trajectory approach. The model is based on reaction zone atoms interacting with a finite number of primary system silicon atoms, which then are coupled to the heat bath, i.e., the bulk solid phase. The potential energy of the Hads‥Hgas interaction is the primary driver of the reaction, and in all reactive collisions, there is an efficient flow of energy from this interaction to the Hads-Si bond. All reactive events occur on a subpicosecond scale, following the Eley-Rideal mechanism. These events occur in a localized region around the adatom site on the surface. The reaction probability shows the maximum near 700K as the gas temperature increases, but it is nearly independent of the surface temperature up to 700 K. Over the surface temperature range of 0-700 K and gas temperature range of 300 to 2500 K, the reaction probability lies at about 0.1. The reaction energy available for the product states is small, and most of this energy is carried away by the desorbing H2 in its translational and vibrational motions. The Langevin equation is used to consider energy exchange between the reaction zone and the bulk solid phase.

• KIEAE Journal
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• v.13 no.2
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• pp.123-130
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• 2013

The primary goal of this research is to identify the impacts of window design on the energy use in buildings which takes up about 25% of the total energy consumption. Recently, efficient use of energy is gaining more importance in buildings. Window design, especially being dependent on glazing performance choices, is an important factor for reducing energy consumption in most of the buildings. It also is influenced by the latitude of the site and window orientation. This paper aims at identifying the influence of Window performance indicators(U-value, SHGC), orientation and latitude on the building energy consumption with systematically designed simulations. Comparative study has been performed for five different locations; Greenland, Korea, Singapore, Argentina and Chile along with the different window U-value and SHGC values. The results show that optimum window system with properly coordinated window performance indicators(U-value, SHGC), orientation achieves dramatic reduction of energy consumptions. Windows with low U-value could reduce heating loads and high SHGC could reduce cooling loads. The study also verifies that the windows installed at south facade is more energy efficient in the northern hemisphere while windows facing north is more energy efficient in the southern hemisphere.

• Journal of Environmental Science International
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• v.12 no.6
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• pp.583-591
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• 2003

The research on potential energy was conducted to conserve the high-exergy energy like primary energy and utilize waste heat from sewage. From the Point of view in using the waste heat, the energy Potential of waste water from the model house was simulated. From the results, when the heated water was supplied to the model house side in order to put unused energy to Practice use, heated water had higher energy Potential than unheated water, which was due to the discharge of most of unused energy. The possessing heat capacity of sewage from heated water was increased to 40-70 percents in comparison with that from the unheated water. Therefore, it can be used as energy source for improving coefficient of performance of heat pumps. By adopting the multiple heat pump into a model house, It showed that the possessing heat capacity of sewage was reduced. It was also found that the heat was recovered as energy source fur multiple heat pump in a model house.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.12
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• pp.802-807
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• 2008

A Study on Typical Rates of Water-use for School Facilities has been carried out in this work. Water supply system is given much weight in school facilities. Therefore, it set up a basis efficiency using of water sources to calculate typical rates of water use. The results are summarized as follows; 1) On the whole, typical rates of water-use was founded out 15 L/stu. d in pirmary school, 10 L/stu. d in middle school and 30 L/stu. d in high school smaller than the existing it. It was rate of water-use change as season and Max. Rates of water-use was July. 2) I deem that school hours are 5 hour's in primary school, 7 hour's in middle school and 8 hour's in high school. It the concept of 1 hour that is lesson time 40 minutes and resting time 10 minutes in primary school, lesson time 45 minutes and resting time 10 minutes in middle school and lesson time 50 minutes and resting time 10 minutes in high school. 3) It is desired that we calculate the volume of pump and water tank throughout this concept and the size of water tank should be 1.5 times with taking peak load into consideration by this study on typical rate of water-use. 4) The amount of using water increases in gradually and I consider the life cycle of facilities is more than 10 years. As a result, I can forecast that the size will be insufficiency but I deem that if we devise a plan about parallel pumping on water tank space, we can cope with it. Also, it is expected that we can cut back the transport energy by controlling pump volume.

• Journal of Korean Society of Rural Planning
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• v.22 no.2
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• pp.109-119
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• 2016

Most of countries are trying to increase the supply of renewable energy as the substitute of the fossil energy for reducing greenhouse gas emissions. However, renewable energy sources account for only about 3.86% of the total Korea primary energy supply. To increase the rate of renewable energy in Korea's energy consumption, various policies for expanding the use of renewable energy should be applied. Also these policies should be consider renewable energy resources distribution and regional inequality. In this study, the potentials of photovoltaic, wind power and bioenergy from rice straw, livestock waste and food waste are calculated and the distribution characteristic and regional inequalities are analyzed using Gini's coefficient and Gini decomposition method. As the results, technical potentials of photovoltaic and wind power of city region(Gu) has more potential rate than theoretical potentials. Livestock waste has the most unequal distribution (Gini's coefficient: 0.617) among renewable resources.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.510-515
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• 2007

A Study on Typical Rates of Water-use for School Facilities has been carried out in this work. Water supply system is given much weight in school facilities. Therefore, it set up a basis efficiency using of water sources to calculate typical rates of water use. The results are summarized as follows ; 1) On the whole, typical rates of water-use was founded out 15 L / stu. d in pirmary school, 10 L / stu. d in middle school and 30L / stu. d in high school smaller than the existing it. It was rate of water-use change as season and Max. Rates of water-use was July. 2) I deem that school hours are 5 hour's in primary school, 7 hour's in middle school and 8 hour's in high school. It the concept of 1 hour that is lesson time 40 minutes and resting time 10 minutes in primary school, lesson time 45 minutes and resting time 10 minutes in middle school and lesson time 50 minutes and resting time 10 minutes in high school. 3) It is desired that we calculate the volume of pump and water tank throughout this concept and the size of water tank should be 1.5 times with taking pick load into consideration by this study on typical rate of water-use. 4) The amount of using water increases in gradually and I consider the life cycle of facilities is more than 10 years. As a result, I can forecast that the size will be insufficiency but I deem that if we devise a plan about parallel pumping on water tank space, we can cope with it. Also, it is expected that we can cut back the transport energy by controlling pump volume.

• Journal of Hydrogen and New Energy
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• v.23 no.1
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• pp.100-109
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• 2012

In this paper, some ideas are proposed to establish the infrastructure of all-electric houses which are able to reduce primary energy consumption and $CO_2$ emission by adopting heat pump systems and induction heating cookers excluding the use of fossil fuel energy. This electrification concept is based on the consumption of only one type of energy which means electricity as secondary energy and the conventional fossil fuel energy is just consumed to generate electricity as primary energy. All-electric house is laid on the extension of the hydrogen economy in a long-term viewpoint so that the effectiveness of this new conceptual house is estimated analyzing the reduction of $CO_2$ emission. In this analysis, the balance of electricity supply and demand is considered including the construction of new power plants by renewable energy such as nuclear, IGCC and fuel cell because decarbonization is an essential element of hydrogen technology and economy and this action is accomplished in both supply and demand side of electricity. The results are able to contribute to develop various useful hydrogen policies and strategies and some detail researches are required previously to make the best application of this new conceptual house.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.151-151
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• 2021

The alarming climate change impacts are demanding the use of renewable energy sources like never before. Hydropower is one of the most cost-effective and environmental friendly energy technology recognized in the world. Big hydropower projects come up with the requirements of huge investment costs along with environmental impacts, whereas small hydropower(SHP) are considered a best solution for the economical source of energy. SHP, basically Run-of-River (RoR) type plants can be sustainable renewable energy sources and given the nature of perennial rivers flowing from steep gradient and rugged topography, feasibility of such plants is equally high in Nepal. The objective of this study is to determine the primary potential sites for the development of RoR type SHP sites using Geo-spatial Information System(GSIS). The use of GSIS enables precise survey of large area within a short period of time. This study has focused on the determination of locations by establishing defined criterions and methodologies and hence have located multiple locations rather than selecting one best location. The approach is applicable for the rapid initial screening of potential locations and results can facilitate detail feasibility study for the technical and economic analysis of SHP in the basin.

• The Transactions of the Korean Institute of Power Electronics
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• v.17 no.2
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• pp.107-113
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• 2012

This paper proposes a PDS(Power Transfer Display separation) method for AC-PDP. The proposed PDS method can transfer power and perform an energy recovery by a power conversion circuit operates differently depending on the time. As a result, it uses less of components than conventional PDP power supply and sustain circuit use. Moreover, the manufacturing process can be streamlined. Therefore, the proposed method is suitable for low cost PDP module. To confirm the operation, validity and features of the proposed PDS method, experimental results from a prototype for 42-in diagonal PDP are presented.