• Journal of the Korean Ceramic Society
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• v.45 no.12
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• pp.766-771
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• 2008

We fabricated single cells with a cathode consisting of a $LaNi_{0.6}Fe_{0.4}O_3-Ce_{0.8}Sm_{0.2}O_{1.9}$ composite (LNF-S20DC composite) active layer and an LNF current collecting layer on a ${0.89ZrO_2}-{0.10Sc_2}{O_3}-0.01{Al_2}{O_3}$ electrolyte sheet. The cathode layers were prepared by the screen-printing method. The cathode properties of these cells were measured by the AC impedance method at $800^{\circ}C$. The cathodes with the ceria-LNF composite active layer exhibited high power performance prior to current loading. We investigated the influence of the mixture ratio of LNF and S20DC on the cathodes properties. The Sm in the ceria particles of the composite cathode was substituted with other rare-earth elements. Cathodes with Pr and Gd co-doped ceria in the active layer provided the better performance than those with Sm- or Gd-doped ceria.

• 한국태양에너지학회:학술대회논문집
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• 2011.04a
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• pp.59-62
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• 2011

The Korea Institute of Energy Research(KIER) has begun collecting horizontal global insolation data since May, 1982 at 16 different locations in Korea and for the more detailed analysis, images taken by geostationary satellite may be used to estimate solar irradiance fluxes at earth I s surface. It is based on the empirical correlation between a satellite derived cloud index and the irradiance at the ground. From the results, the measured data has been collected at 16 different stations and estimated using satellite at 23 different stations over the South Korea from 1982 to 2000. The Result of analysis shows that the armual-average daily global radiation on the horizontal surface is $3.56kWh/m^2/day$ and Estimated solar radiation fluxes show reliable results for estimating the global radiation with average deviation of -7.27 to +3.65% from the measured values.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.612-618
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• 2009

Recently the roles of railways about the prevention of global warming caused by greenhouse gases and for low carbon green growth are larger than ever. And the railroad-related research institutions have been active in researching for energy conservation. Especially the urban railroad has been emerged as the best means of transportation compared to the general public transportation systems in punctuality, stability, ecology and etc. In operating the urban railroad system there are various ways for energy savings. In the larger category, One is the hardware aspect according to the structure of the vehicle and the development of control systems. The other is the software aspect which efficient train operation can be made through control of driving patterns and driving diagram. In this paper, there is sense to analyze the result in verifying expectation relation with variable and the use of electric power on this after selecting main variables that can influence to the energy of the train operation in the software aspect. First, after collecting the basic data related to operation(train speed, operating hours, power consumption, the position of stopping station, electrical power system etc.) and according to this, investigating the consumption of the energy of the operation, in the side of energy consumption deducing and analyzing problem, this will be found solutions.

• Journal of the Korean Ceramic Society
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• v.52 no.5
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• pp.304-307
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• 2015

To reduce the lateral conduction loss of thin-film-processed cathodes, the microstructure of the thin-film cathode is engineered to contain a denser bridging layer in the middle. By doing so, the characteristic crack-like pores that separate the cathode domains in thin-film-processed cathodes and hamper lateral conduction are better connected and, as a result, the sheet resistance of the cathode is effectively reduced by a factor of 5. This induces suppression of the lateral conduction loss and expansion of the effective current collecting area; the cell performance is improved by more than 30%.

• Korean Journal of Poultry Science
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• v.10 no.1
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• pp.46-52
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• 1983

The study was carried out to examine factors affecting metabolic plus endogenous one.9y (FEm＋UEe) losses by adult roosters. Experiment one was performed to examine the effect of excreta collecting period and Experiment two, of feeding soluble carbohydrates (corn starch and glucose) to birds on FEm＋UEe losses. The results obtained were as follows : 1. The excreta voided, energy and energy losses by the roosters during collecting period II (24-48hr) were generally higher than those of period I, at though there was no significant difference (P＞.05). 2. There was not found correlationship between body weight (X) and excreta voided, energy and nitrogen losses IY) (P＞.05). The fact supported that body weight of birds did noy affect the losses of FEm＋UEe by adult rooster. 3. The feeding of glucose and mixture (corn starch＋glucose) decresed excreta voided, energy and nitrogen losses significantly (P＜.05) comparing with those of unfed birds. 4. The excreta voided, and nitrogen loss of birdsfed corn starch were much lower thu those of unfed birds. Fact that FEm＋UEe losses was not significantly different (P＞.05) between birds fed corn starch and unfed birds was indicative that apparent digestibility of corn starch was much lower than that of glucose ana mixture. 5. Nitrogen loss of fed birds was greatly reduced comparing with that of fed birds. The finding was indicative that the carbohydrates input was ultilized to supplemented energy loss through the catabolism of body tissue during fasting.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.63.1-63.1
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• 2010

Since the solar energy resource is the main input for sizing any solar photovoltaic system and solar thermal power system, it is essential to utilize the solar radiation data as a application and development of solar energy system increase. It will be necessary to understand and evaluate the insolation data. The Korea Institute of Energy Research(KIER) has begun collecting horizontal global insolation data since May, 1982 at 16 different locations in Korea and for the more detailed analysis, Images taken by geostationary satellite may be used to estimate solar irradiance fluxes at earth's surface. It is based on the empirical correlation between a satellite derived cloud index and the irradiance at the ground. From the results, the measured data has been collected at 16 different stations and estimated using satellite at 23 different stations over the South Korea from 1982 to 2009. The Result of analysis shows that the annual-average daily global radiation on the horizontal surface is $3.56kWh/m^2/day$.

• International Journal of Contents
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• v.7 no.1
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• pp.8-13
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• 2011

For energy-efficiency in Wireless Sensor Networks (WSNs), when a sensor node detects events, the sensing period for collecting the detailed information is likely to be short. The lifetime of WSNs decreases because communication modules are used excessively on a specific sensor node. To solve this problem, the TARP decentralized network packets to neighbor nodes. It considered the average data transmission rate as well as the data distribution. However, since the existing scheme did not consider the energy consumption of a node in WSNs, its network lifetime is reduced. In this paper, we propose an energy awareness congestion control scheme based on genetic algorithms in WSNs. The proposed scheme considers the remaining amount of energy and the transmission rate on a single node in fitness evaluation. Since the proposed scheme performs an efficient congestion control, it extends the network lifetime. In order to show the superiority of the proposed scheme, we compare it with the existing scheme through performance evaluation. It is shown that the proposed scheme enhances the data fairness and improves the network lifetime by about 27% on average over the existing scheme.

• The Journal of the Acoustical Society of Korea
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• v.22 no.4
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• pp.323-328
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• 2003

This study describes an energy contour generation method for Korean n systems. We propose a vector-regression tree, which is a vector version of a scalar regression tree. A vector-regression tree predicts a response vector for an unknown feature vector. In our study, the tree yields a vector containing ten sampled energy values for each phone. After collecting 500 sentences and its corresponding speech corpus, we trained trees on 300 sentences and tested them on 200 sentences. We construct a bagged tree and a born again one to improve the performance of contour prediction. In the experiment, we got a 0.803 correlation coefficient for the observed and predicted energy values.

• Journal of the Korean Solar Energy Society
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• v.28 no.1
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• pp.51-56
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• 2008

Since the direct normal insolation is a main factor for designing any solar thermal power system, it is necessary to evaluate its characteristics all over the country. We have begun collecting direct normal insolation data since December 1992 at 16 different locations and considerable effort has been made for constructing a standard value from measured data at each station. KIER(Korea Institute of Energy Research)'s new data will be extensively used by solar thermal concentrating system users or designers as well as by research institutes. From the results, we can conclude that 1) Yearly mean $2.67\;kWh/m^2/day$ of the direct normal insolation was evaluated for all days all over the 16 areas in Korea. 2) All day's direct normal insolation of spring and summer were $2.91\;kWh/m^2/day$ and $2.23\;kWHm^2/day$, and for fall and winter their values were $2.78\;kWh/m^2/day$ and $2.77\;kWh/m^2/day$ respectively. So, spring, fall and winter were higher, and summer was lower than the yearly mean value.

• Proceedings of the SAREK Conference
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• 2005.11a
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• pp.173-178
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• 2005

Recently. we interested in renewable energy due to cost increase of the crude oil, etc. In this study solar assisted hybrid heat pump system that uses the solar heat and air as heat source analyzed by experimentally.'rho system could runs at dual mode. One is thermal storage mode of solar energy at day time and the other is heat pump mode with low temperature air as heat source at night time. In case of setting temperature over the limited range. high temperature water heated at the solar energy collecting tubes supplied to the storage tank. As results. it is founded that the heat pump performance Is higher than general heat pump which using the only air as a heat source. The developed system could be used as main healing equipment for the panel heating for the residential house.