• Proceedings of the KSR Conference
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• 2011.10a
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• pp.2336-2341
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• 2011

The studies on railway vehicles equipped with various energy storage system is proceeded actively. These have a lot of advantages like the maximizing reuse of the regeneration energy, the decrease of peak power in catenary and the reduction of infrastructure costs through catenary-free travelling. This paper is focused on the development of the TPS (Train Performance Simulation) program for railway vehicles equipped with energy storage system. The battery and ultra-capacitor system are modeled using Matlab/Simulink among several energy storage systems. And the feasibility of simulation model is evaluated with the basic power distribution algorithm.

• Carbon letters
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• v.3 no.4
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• pp.205-209
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• 2002

In the reaction of gas-solid phases, the microwave energy plays a role as a catalyst, because it causes friction between adjacent molecules and enables an unique characteristics of interior heating of the materials. When the dipole gases are adsorbed inside of the pore of carbon materials, the gases are decomposed by the microwave energy and reacted with the carbon atoms. Using this principle, we could make the activated carbon from coconut shell within 20 minute, and this residence time for activation is about 1/16 of rotary kiln. The BET surface area of activated carbon made by microwave is about $1,100m^2/g$ similar to conventional method of rotary kiln. In this study, the power of microwave generator was 400~1000W, and the gas for activation was steam mainly.

• Journal of Mechanical Science and Technology
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• v.16 no.10
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• pp.1287-1295
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• 2002

In this work, the fuel economy of a parallel hybrid electric vehicle is investigated. A vehicle control algorithm which yields operating points where operational cost of HEV is minimal is suggested. The operational cost of HEV is decided considering both the cost of fossil fuel consumed by an engine and the cost of electricity consumed by an electric motor. A procedure for obtaining the operating points of minimal fuel consumption is introduced. Simulations are carried out for 3 variations of HEV and the results are compared to the fuel economy of a conventional vehicle in order to investigate the effect of hybridization. Simulation results show that HEV with the vehicle control algorithm suggested in this work has a fuel economy 45% better than the conventional vehicle if braking energy is recuperated fully by regeneration and idling of the engine is eliminated. The vehicle modification is also investigated to obtain the target fuel economy set in PNGV program.

• Journal of Environmental Impact Assessment
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• v.8 no.1
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• pp.141-146
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• 1999

This paper proposes the planning and design of the Eco-village centering around Chindo-ri, Muju-kun. The Eco-village project has three basic objects the Eco-village residents' lives adapting to ecological principles such as regeneration and circulation, life agricultural techniques based on organic cycle, and residents' harmonious lives with the surrounding nature. For constructing of the Eco-village, first, the subject area was analyzed in terms of the natural and cultural environment and then, on this analytic ground the concrete concept and the specific plan were set up. The following details also should be considered: the scale of the residential household, the population, the space arrangement of the village, the material cycling structure, the waste treatment, the purification of the sewage, the energy supply, the landscape architecture, the production activity, the conservation of the ecosystem and so on.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.322-327
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• 2007

Dedicated outdoor air-conditioning(DOA) system that utilizes pre-cooling and desiccant dehumidification can be superior to conventional cooling and reheating system with respect to energy consumption and indoor thermal comfort. In this work, simulation has been conducted to study various factors that affect the performance of DOA. Dynamic simulation shows the transient variation of temperature and humidity as the on/off control logic is imposed. Exit humidity of process air and flow rate are varied to study the effect on exit temperature of process air, dehumidification quantity, required regeneration temperature and exit humidity of regeneration air. For an outdoor air condition of $28.5^{\circ}C$ temperature, 16 g/kg humidity ratio and 2000 cmh flow rate, the dehumidification efficiency is increased by 4.6% as the flow rate is doubled.

• KEPCO Journal on Electric Power and Energy
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• v.6 no.3
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• pp.297-303
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• 2020

The reaction of carbon dioxide with the amine-based absorbents which have various substituents in the molecule was described. In the case of MEA which is a representative primary amine, the absorption reaction was proceeded very fast while the regeneration reaction was took place slowly due to the strong bond strength between the absorbent and carbon dioxide. The more substituents on N atom of the absorbent, the slower the absorption reaction between carbon dioxide and the absorbent, which in turn causes faster the regeneration rate from the reaction intermediate, carbamate.

• KIEAE Journal
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• v.16 no.2
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• pp.23-31
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• 2016

Purpose: Recently energy consumption is rapidly increasing due to continuous development of social evolution in various field. In this situation, there is a lot of effort to reduce this energy consumption in many ways, especially in building energy. Preceding studies already started to analyze the housing area such as zero energy house and passive house by researching annual building energy consumption, but to apply the results of housing to office building is insufficient since it has different consumption tendency. Method: In this study, eQuest program was used for simulation and the base model is selected among standard office building in ASHRAE 90.1. Variables are divided into passive and active factors for comparison. Result: In passive factors, glazing system showed the highest energy saving rate by 21.3% with triple low-e glass and enhancing wall u-value showed the lowest energy saving rate by 3.6% with 0.15 m2/K. In active factors, VAV system showed 30.9% energy saving rate when compared to CAV system, and heat exchanger showed 10.2% energy saving rate. For regeneration energy part, photovoltaic panel generated 10.4% of base annual energy usage.

• Korean Journal of Materials Research
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• v.24 no.6
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• pp.310-318
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• 2014

In this experiment, a highly porous scaffold of biphasic calcium phosphate (BCP) was prepared using the spongereplica method. The BCP scaffold was coated with 58S bioactive glass (BG) and sintered for a second time. The resulting scaffold was coated with gelatin (Gel) and cross-linked with [3-(3-dimethyl aminopropyl) carbodiimide] and N-Hydroxysuccinamide (EDC-NHS). The initial average pore size of the scaffold ranged from 300 to $700{\mu}m$, with more than 85 % porosity. The coating of BG and Gel had a significant effect on the scaffold-pore size, decreasing scaffold porosity while increasing mechanical strength. The material and surface properties were evaluated by means of several experiments involving scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) and X-ray diffraction (XRD). Cytotoxicity was evaluated using MTT assay and confocal imaging of MC3T3-E1 pre-osteoblast cells cultured in vitro. Three types of scaffold (BCP, BCP-BG and BCP-BG-Gel) were implanted in a rat skull for in vivo evaluation. After 8 weeks of implantation, bone regeneration occurred in all three types of sample. Interestingly, regeneration was found to be greater (geometrically and physiologically) for neat BCP scaffolds than for two other kinds of composite scaffolds. However, the other two types of scaffolds were still better than the control (i.e., defect without treatment).

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.5
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• pp.96-104
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• 2004

This paper proposes a dc power regenerating systems, which can generate the excessive dc power from dc bus line to ac supply in substations for traction system The proposed regeneration inverter system for dc traction can be used as both an inverter and an active power filter(APF). As an regeneration inverter mode, it can recycle regenerative energy caused by decelerating tractions and as an active power filter mode, it can compensate for harmonic distortion produced by the rectifier substation. From the viewpoint of both power capacity and switching losses, the system is designed on the basis of three phase PWM inverters and composed of parallel inverters, output transformers, and an LCL filter.

• Korean Journal of Veterinary Pathology
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• v.1 no.1
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• pp.1-6
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• 1997

The cellularity and composition of the spleen lymph node thymus and peripheral blood and tempo of regeneration were studied at various time points after syngeneic bone marrow transplantation(BMT) in C3H/Hen mice. Significant depression of absolute lymphocyte count was noted on week 1 after lethal whole-body irradiation and BMT. In comparison to the lymph node thymus and spleen had an rapid regeneration of cellularity. The distinct cell populations($CD4^+,\;CD8^+,\;CD28^+,\;B220^+) have determined in the lymphoid tissue of mice subjected to irradiation. The relative representation of these subpopulations was significantly different from that in nonirradiated control. $CD4^+\;and\;CD8^+$ cells were present in very low numbers whereas the $B220^+$ cells reached more than normal range at 2 weeks after BMT. The number of $CD4^+$ cells returned to normal relatively soon than $CD8^+$ cell. At week 4 after BMT, the cellularity and composition of spleen lymph node and peripheral blood lymphocyte reached about 50% of the normal range therefore we can choose this time point for the other tests of immune function after BMT.