• Proceedings of the Korean Vacuum Society Conference
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• 2009.02a
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• pp.235.1-235.1
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• 2009

• Proceedings of the Korean Ceranic Society Conference
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• 2002.10a
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• pp.95.1-95
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• 2002

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1129-1129
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• 2009

Here the improved performance of polymer/polymer solar cells, which are of importance to achieve real plastic solar cells in the near future, is reported. First, the progress in polymer/polymer solar cells is briefly reviewed and then the limiting factors are discussed in terms of charge transport.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.32 no.6
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• pp.205-210
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• 1983

This paper presents a steady-state computer solution of the fundamental semiconductor one-dimensional transport equations, describing a single (metal-semiconductor) contact device, involving only one type of charge carrier. The computations are conveniently made by the

• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.12
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• pp.1646-1654
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• 2002

A two-phase closed thermosyphon was one of the most effective devices in the removing heat because of its simple structure, thermal diode characteristics, wide operating temperature range and so on. In this study, a two-phase closed thermosyphon(working fluid PFC(C6F14), container copper(inner grooved surface)) was fabricated with a reservoir which can change the fill charge ratio. The experiments were performed in the range of 50~600W heat flow rate and 10~70% fill charge ratio. The results were compared with some correlations that were presented by Rohsenow and Immura et al. in the evaporator, by Nusselt, Gross and Uehara et al. in the condenser and by Cohen and Bayley, Wallis, Kutateladze and Faghri et al. in heat transfer limitation etc.. The heat transfer coefficient at the evaporator increased with the input power. However the effect of the fill charge ratio was nearly negligible. At the condenser, it showed an opposite trend to the evaporator and with increase of the fill charge ratio, showed some enhancement of heat transfer. The heat transport limitation was occurred by the dry-out limitation for small fill charge ratio(10%) and presented about 100W. For the case of large fill charge ratio(Ψ$\geq$40%), it was occurred by the flooding limitation at about 500W.

• Journal of Energy Engineering
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• v.20 no.4
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• pp.278-285
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• 2011

Computational modelling and simulation for the charge-discharge characteristics of Lithium-ion batteries have been carried out. The battery system consists of a simplified 2-dimensional single cell for the modelling, in which the thermal modelling on the charge-discharge characteristics was conducted in the temperature range from 288 K through 318 K by using FEMLAB as an engineering PDE solver. While material parameters adopted in the present modelling were dependent on the system temperature, their thermal modelling were applied on the simulations of the charge-discharge period and the rate of transferring charges systematically. The resulting simulation shows that the cycle of the charge-discharge shorten itself by reducing the system temperature, regardless of the charge-discharge rates. In addition, the mass-transport phenomena of Lithium ion have been discussed in connection with the charge-discharge characteristics in the battery.

• The Korean Journal of Emergency Medical Services
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• v.12 no.1
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• pp.5-15
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• 2008

Purpose : Centering on users(patients) who are offered the patient transport service by the emergency medical service system in our country, the use and satisfaction are analyzed with the transport service in 119 Emergency Medical Service System and Private transport agent. Results : 1. As for personnel in ambulance cars, 119 emergency staff showed a higher boarding rate of the first-class emergency medical technicians than private transportation centers : 48.4% and 17.7%, respectively. 2. Private transportation centers showed higher user satisfaction with transportation service than 119 emergency staff, which was not statistically significant. 3. As for the case that needs to receive the transport service in the future, the ratio with the will to use 119 Emergency Medical Service System(70.9%) was indicated to be much higher than the ratio of the private transport agent(29.1%). Suggestions : First, Centers transporting first-aid patients should essentially secure a sufficient number of first-class emergency medical technicians as professional emergency medical staff to reinforce qualitative improvement in emergency medical service. Second, It is necessary to establish a systematic monitoring system and develop educational programs in order to enhance satisfaction with the use of 119 emergency staff. Third, the government or the local government needs to positively support and guide the private transport agent, which is in charge of the public medical service.

• Korean System Dynamics Review
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• v.11 no.2
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• pp.45-75
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• 2010

Today, the logistics industry has played a critical role in national economy activities. The low cost and high efficiency of the logistics industry are meaningful in the improvement of national competitiveness and the logistics industry. However, efficiency of logistics is lower than that of the United States and Japan since most quantities are processed in road transportation in Korea. With regard to this, existing studies expected a saving of social and environmental costs due to a decrease of road transportation as well as improvement of logistics productivity due to bulk transportation through activation of rail and costal transport. For the expectation, the existing multimodal transport systems should be improved first. Therefore it aimed to develop scenario-based simulation models of multimodal transport systems for decision makers in charge of improvement in the logistics area. For model development, this study utilized Thinking Process and System Dynamics(TP-SD) methodology.

• Proceeding of EDISON Challenge
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• 2013.04a
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• pp.273-277
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• 2013

We apply a density functional theory (DFT) and DFT-based non-equilibrium Green's function approach to study the electronic and transport properties of graphene nanoribbons (GNRs) co-doped with boron-nitrogen, nitrogen-phosphorus and boron-phosphorus. We analyze the structures and charge transport properties of co-doped GNRs and particularly focus on the novel effects that are absent for the single N-, B-, or P-doped GNRs. It is found that co-doped GNRs tend to be doped at the edges and the electronic structures of co-doped GNRs are very sensitive to the doping sites. Also, in case of B-N and B-P co-doped GNRs, conductance dips of single-doped GNRs disappeared with the disappearance of localized states associated with doped atoms. This may lead to a possible method of band engineering of GNRs and benefit the design of graphene electronic devices.

• The Transactions of the Korea Information Processing Society
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• v.4 no.4
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• pp.1100-1105
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• 1997

The verial black stripe is one of the defects in a chrge-coupled device(CCD). Vertical black stripes are caused by some signal chrges which fail to transport form the vertical CCD region to the horizontal one. The defective transport of signal charges orignates in the potential barrier with the narrow width effects in the verti-cal-horizintal interface stuccture. The vertical black stripes show up when the charge transfer dfficiency is less than 99.2% under the low illumination condition. In this research, we designed and developed a new vertical-horizontal interface structre of a delta type, thus marking it possible to eliminate the vertical black stripes.