• Journal of Advanced Marine Engineering and Technology
• /
• v.29 no.8
• /
• pp.883-890
• /
• 2005

The industrial growth and the raised living quality have led to the massive energy consumption. As a result. the polluted environment and the limited amount of energy resources emerged as serious problems to be resolved in 21st century. Especially, in the case of Korea whose imported energy dependency rate is 98.2$\%$ in 2003 and constantly increasing every rear. more than 24$\%$ of overall energy consumption is for housing and commercial use. In order to cope with the shortage of natural energy resources, it is inevitable to develop alternative sustainable energy resources including seawater heat. so that they can replace existing resources. The heat transfer air velocity 3.5 m/s is proper to consideration with the body the pipe size 200A is more suitable than look due to the air velocity quantify and the ratio of pipe surface area. And the error between experimental data with simulation is below 5.34$\%$ so the suggested equation for calculating heat transfer capacity can be used. Therefore out of many methods utilizing seawater heat. this work Presents the efficiency of using sea water heat as a resource for air-conditioners which can be converted from the outside air through the air-to-heat conversion tube . Consequently. this method provides pretty reasonable energy efficiency.

• Journal of the Korean Applied Science and Technology
• /
• v.30 no.3
• /
• pp.480-487
• /
• 2013

Bioenergy is classified to one of the renewable energy resources such as solar, wind, hydro and tidal energies. It should be noted that all the renewable energies contribute to the reduction of greenhouse gases emission. In some cases, energy from wastes was also categorized as a renewable energy in our country even though it has only negligible effect on the emission reduction. In this paper, we tried to identify the bioenergy in order to follow the global indices of the renewable energy. The indices evaluated here were whether a resource is renewable, biogenic, biodegradable, combustible and organic. Biogenic and combustible were selected as the indices to identify the bioenergy. It was also suggested that combustible as an index can be exchangeable to organic.

• Journal of the Korean Solar Energy Society
• /
• v.38 no.4
• /
• pp.43-54
• /
• 2018

In this study, we assessed dependency of small hydropower potentials on the two different runoff such as the estimated runoff based on the rainfall amounts and measured runoff. The hydpropower potentials were evaluated using actural power generations taken from Deoksong, Hanseok, and Socheon small hydropower plants over Han and Nakdong river basins, respectively. As a result of comparing the actual power generation amount with the potential amount based on the rainfall amount and the estimated amount based on the observed flow amount by each small hydroelectric power plant, the degree of latent small hydro energy by the observed flow was confirmed to be high. It is confirmed that the potential hydroelectric power generation rate is estimated to be about average 30%Point higher than the actual generation amount as a result of the measured flow rate rather than using the rainfall amount. Based on this, a method for improving the degree of the actual generation amount is proposed.

• New & Renewable Energy
• /
• v.6 no.2
• /
• pp.12-18
• /
• 2010

This paper reviews commercial wind mapping services provided by the oversea consulting companies, AL-PRO and anemos in Germany, AWS Truepower and 3TIER in USA. They provide quick-to-use but essential dataset for a preliminary assessment before commencing an actual feasibility study for wind farm development. Details of wind mapping method, mapresolution, data extraction height, price and so forth are compared and fresh service contents such as site analysis report are drawn from the comparison. Despite its public service, the objective value of the Renewable Energy Resource Map System of Korea Instistute of Energy Research is also confirmed and it is anticipated that the drawn new content idea will be ported to the system to enrich its applicability.

• KEPCO Journal on Electric Power and Energy
• /
• v.2 no.4
• /
• pp.569-575
• /
• 2016

In this paper, we propose a method to develop a static equivalent model of an inverter-based distributed energy resource (DER), where the model is used for a steady-state fault analysis of a power grid. First, we introduce the characteristics of an inverter-based DER as well as its general configuration. Then, we derive the equivalent model of the DER on the basis of the characteristics. Last, the performance of the proposed method is proven by the results of computer simulations.

• 한국신재생에너지학회:학술대회논문집
• /
• 2009.06a
• /
• pp.557-560
• /
• 2009

When we urgently need to develop and supply an alternative energy, wind power is growing with much interest because it has relative low cost of power and area of tower. To estimate the wind power resource, it is necessary to make an observation first. Although the large wind falm and resources are near coast and mountain area, the wind energy in urban area has the strong thing of direct access to power generator. In this study, we estimate the probability of wind energy above urban area using SODAR data, which is located at the top of the tall building (140m).

• Bulletin of the Korean Chemical Society
• /
• v.32 no.8
• /
• pp.2599-2606
• /
• 2011

The fluorescence of ethidium bound to DNA, poly[d(A-T)$_2$], and poly[d(G-C)$_2$] at a [ethidium]/[DNA] ratio of 0.005 was quenched by porphyrins when both ethidium and the porphyrins simultaneously bound to the same polynucleotide. The quenching was tested using the "inner sphere" and the "Forster resonance energy transfer" (FRET) models, with the latter found to contribute, at least in part, to the quenching. Meso-tetrakis(N-methylpyridinium-4-yl)porphyrin (TMPyP) exhibited a higher quenching and FRET efficiency than cis-bis(N-methylpyridinium-4-yl)porphyrin (BMPyP) for all of the tested DNA and polynucleotides, demonstrating that energy transfer efficiency is affected by the number of positive charges of porphyrins.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.35 no.7A
• /
• pp.660-668
• /
• 2010

In energy resource constrained networks, the network lifetime can be enhanced by optimally allocating energy resource among users based on the available channel state information and the residual energy information at each node. In this paper, we propose the relay selection scheme and power allocation scheme to maximize the network lifetime in wireless relay networks with capacity constraint. The computer simulation results show that the proposed scheme increase the network lifetime in comparison to the conventional schemes.

• Journal of Environmental Science International
• /
• v.12 no.3
• /
• pp.359-366
• /
• 2003

Ecological society and energy conservative systems has become a subject of world wide attention. To examine the technologies of such systems as resource recycling society, this study is proposed for using rainwater as energy source and water resources in urban area. Useful informations for planning of utilizing rainfall as energy source, water resources, emergency water and controlling flood are discussed with model systems in urban area. It is calculated that the rate of utilizing rainwater, amounts of utilizing rainwater, substitution rate of supply water, amounts of overflow rainwater according to rain storage tank volume. By applying the past weather data, The optimum volume of rain water storage was calculated as 200m$^3$ which mean no benefits according to the increase of storage tank volumes. For optimum planing and control method at the model system, several running method of rainwater storage tank was calculated. The optimum operating method was the using weather data as 3hours weather forecast.

• Environmental and Resource Economics Review
• /
• v.10 no.4
• /
• pp.569-589
• /
• 2001

We examine historical contributions of inter fuel substitution, changes in carbon efficiency and energy intensity, growth of economy and population to Korea's $CO_2$ emissions from 1970 to 1998 using the log mean weight Divisia index method. The study reveals that economic growth is the most significant factor to $CO_2$ emissions growth among the five factors. Changes in the fuel substitution and carbon coefficient are found negative contributors to $CO_2$ emissions growth. Energy intensity, which played dominant role in halting $CO_2$ emissions growth in the 1980s, began to play reversed role in the 1990s. When evaluated with the log mean Divisia index technique, deterioration of energy intensity in the 1990s is found worse and expected to contribute $CO_2$ emissions growth further.