• Title/Summary/Keyword: Transport efficiency

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Enhanced efficiency of organic light-emitting diodes by doping the holetransport layer

  • Kwon, Do-Sung;Song, Jun-Ho;Lee, Hyun-Koo;Shin, You-Chul;Lee, Chang-Hee
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07b
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    • pp.1401-1403
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    • 2005
  • We present that the carrier balance can be improved by doping a hole transport layer of 4,4'- bis[N-(1-napthyl)-N-phenyl-amino]-biphenyl (${\alpha}$-NPD) with a hole blocking material of 2,9-dimethyl- 4,7-diphenyl-1,10-phenanthroline (BCP). The doping leads to disturb hole transport, which can enhance the balance of electron s and holes concentration in the emitting layer, aluminum tris(8 -hydroxyquinoline) (Alq3), resulting in enhanced electroluminescence (EL) quantum efficiency for the device with the doped ${\alpha}$-NPD.

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Electrical and Optical Properties of Organic Light Emitting Devices Using Blue Fluorescent and Orange Phosphorescent Materials (청색형광재료와 황색인광 재료를 이용한 OLEDs의 전기 및 광학적 특성)

  • Seo, Yu-Seok;Moon, Dae-Gyu
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2010.06a
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    • pp.155-155
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    • 2010
  • We have investigated organic light-emitting devices by doping phosphorescent orange and fluorescent blue emitters into the separate layers of single host. The electroluminescence spectra and current efficiency were strongly dependent on the location of each doped layers. The luminance-voltage (L-V) characteristics of the device2 (ITO/Hole Transport Layer/Orange Phosphorescent emissive layer/Blue Fluorescent emissive layer/Electron Transport Layer/liF/Al) showed the maximum current efficiency of 19.5 cd/A.

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A study on advanced EMU's maintenance program on test operation in Dabul line (차세대 전동차 대불선 시운전 시 유지보수방안 연구)

  • Kim, Young-Kyu;Park, Se-Young;Song, Jeong-Hun;An, Cheon-Heon;Lee, Han-Min
    • Proceedings of the KSR Conference
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    • 2010.06a
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    • pp.2215-2222
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    • 2010
  • Advanced EMU have been enhanced in terms of safe transport and maintainability. It is a new urban railway technology that enables an operation institution to cut repair and maintenance costs and customers to use convenient service at lower costs based on IT technology. If a development vehicle of Advanced EMU is completed, it will be used to test the entire advanced EMU system through sufficient performance check and reliability check prior to operation in commercial line. It will also verify efficiency, safety, punctuality and energy efficiency of transport. Accordingly, it is necessary to figure how to repair and maintain vehicles to enhance safety of Advanced EMU system in cooperation with operation during the period of comprehensive evaluation on the operation of a development vehicle in a test line. In this paper, we investigated the maintenance program of Advanced EMU on test operation in Dabul line. The test condition and operation environment of Advanced EMU in Daebul line was analyzed.

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Experimental Study of a High Efficiency Transport Refrigeration Container under Cooling and Defrosting Conditions (고효율 냉동 컨테이너의 냉각 및 제상 실험)

  • Mun, Je-Cheol;Ardiyansyah, Ardiyansyah;Choi, Kwang-Il;Oh, Jong-Taek
    • Proceedings of the SAREK Conference
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    • 2008.06a
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    • pp.277-281
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    • 2008
  • This paper presents the development of a high efficiency transport refrigeration system for sliced-raw fish transportation. The refrigeration system is equipped with heat storage for reverse cycle-hot gas defrost (the stored heat is used during defrost cycle of the system). System performance and container operating conditions are analyzed during experimental investigation on a $3,225{\times}1,740{\times}1,640\;mm$ full-scale refrigerated container under cooling and defrosting conditions. The prototype system indicates better performance in terms of shorter cooling-down time, shorter defrost time and smaller fluctuations of refrigerated container's temperature.

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Productivity growth in Korean Railway Transport (우리나라 철도수송의 생산성 변화)

  • Kim, Hyun-Woong;Kook, Kwang-Ho;Moon, Dae-Seop
    • Proceedings of the KSR Conference
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    • 2009.05a
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    • pp.378-381
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    • 2009
  • This paper investigates the productivity growth in Korean railway transport. The productivity growth is calculated by a process of measuring of pure efficiency change index(PECI), scale efficiency change index(SECI), and technical change index(TCI), using Data envelopment analysis (DEA) method. The data cover the period 1999$\sim$2006; 1999$\sim$2003 are the pre-structural reform years and the post-structural reform years are 2004$\sim$2006. The framework for the analysis is Malmquist Productivity Index (MPI) of the to investigate the impacts of structural reform on productivity growth, respectively. The inputs considered are the length of operating line, the number of staff, the number of coach and wagon, and the outputs are the trains movement of passenger and freight, and the traffic of passenger and freight. Results indicate that Korean railway experienced a annual productivity growth of approx. 3% after the structural reform.

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Electrical and Optical Characteristics of QD-LEDs Using InP/ZnSe/ZnS Quantum Dot (InP/ZnSe/ZnS 양자점을 이용한 QD-LED의 전기 및 광학적 특성)

  • Choi, Jae-Geon;Moon, Dae-Gyu
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.27 no.3
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    • pp.151-155
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    • 2014
  • We have developed quantum dot light emitting diodes (QD-LEDs) using a InP/ZnSe/ZnS multi-shell QD emission layer. The hybrid structure of organic hole transport layer/QD/organic electron transport layer was used for fabricating QD-LEDs. Poly(4-butylphenyl-diphenyl-amine) (poly-TPD) and tris[2,4,6-trimethyl-3-(pyridin-3-yl)phenyl]borane (3TPYMB) molecules were used as hole-transporting and electron-transporting layers, respectively. The emission, current efficiency, and driving characteristics of QD-LEDs with 50, 65 nm thick 3TPYMB layers were investigated. The QD-LED with a 50 nm thick 3TPYMB layer exhibited a maximum current efficiency of 1.3 cd/A.

The Study of Efficiency of System Architecture According to the Modeling of 40G Aladdin System and Input Traffic (40G급 Aladdin 시스템의 모델링 및 입력 트래픽에 따른 시스템 구조 효율성 연구)

  • Hwang, Yu-Dong;Park, Dong-Gue;Jang, Jong-Soo
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.11 no.4
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    • pp.121-130
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    • 2012
  • In this paper, the structure of the Aladdin system was modeled by Petri nets for performance evaluation of 40G bps class Aladdin system which was developed in ETRI as the high-speed DDoS defensive tool. The efficiency analysis of the system architecture according to the input traffic of the Aladdin system was performed based on the modeling.

Electroluminescence characteristics of organic light-emitting diodes with TPD doped PVK as the hole transport layer

  • Shin, Y.C.;Song, J.H.;Lee, C.H.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07b
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    • pp.1404-1407
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    • 2005
  • We have fabricated organic light-emitting diodes using poly(N-vinylcarbazole)(PVK) doped with N,N'- diphenyl-N,N'-bis(3-methylphenyl)-[l,l'-biphenyl]- 4,4/-diamine (TPD) as the hole transport layer. TPD molecules act as the trapping sites in PVK and reduce the hole mobility, which can enhance the electronhole balance in the emitting layer, resulting in the enhanced device performance. We have found the optimum ratio of TPD to PVK for the EL efficiency.

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An analysis on the headway of urban rail transit (도시철도 시스템에서의 운행 시격 분석)

  • Bang, Yung;Kim, Hyung-Hoon;Um, Jung-Kyou;Cho, Yong-Gi
    • Proceedings of the KSR Conference
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    • 2006.11b
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    • pp.1495-1500
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    • 2006
  • A signal system is critical point of transport capacity and train operation in urban rail transit. Today the moving block system by radio is taking place of the fixed block system by track circuit for efficiency and short headway in underground railway and right rail transit. In this study, assuming specification of a train, track and control system, the minimum headway on the moving block system and the fixed block system is researched for the maximum transport capacity.

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Report of 2050 Energy Technology Perspectives 2015 and Activities on IEA/ECERC Delegation of Korea (2050 에너지기술전망 (2015판) 및 국제에너지기구 활동 보고)

  • Bae, Choongsik
    • 한국연소학회:학술대회논문집
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    • 2015.12a
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    • pp.279-282
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    • 2015
  • Energy Technology Perspectives (ETP) has provided the current status of energy system, technology developments and external events that have changed ETP scenario since 2006. The three scenarios are presented in four different fields (power generation, transport, industry, building). Energy efficiency improvement of energy system and the new system that can solve the increasing energy demand and the emissions are introduced. The activities on IEA/ECERC delegation of Korea will be also reported in this presentation.

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