• Title/Summary/Keyword: Transport Layer

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The Role of Fronts on the Vertical Transport of Atmospheric Pollutants I: 2D frontal model experiment (대기오염물질의 연직 수송에 미치는 전선의 역할 I: 2차원 전선모델을 이용한 수송 실험)

  • Nam, Jae-Cheol;Thorpe, Alan
    • Atmosphere
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    • v.14 no.3
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    • pp.29-40
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    • 2004
  • It is well known that convections and fronts are the most effective weather systems for the vertical transport of pollutants. I used a two dimensional front model in order to investigate the mechanism of the vertical transport of atmospheric pollutants between planetary boundary layer(PBL) and free atmosphere by fronts. The main dynamic processes which contribute the vertical transport of pollutants are advection and diffusion. The transported amount of pollutant from the boundary layer to the free atmosphere increases dramatically during the developing stage of the front. 46% of pollutants are transported vertically within 12 hour and 54% are transported within 24 hour. In the meantime, compared to the total amount of pollutants transported by both advection and diffusion, about 25% (30%) less pollutants are transported when only advection (diffusion) process in included in the model. The most important mechanism for the vertical transport is vertical advection, while the vertical diffusion process plays an important role in the redistribution of pollutants in the PBL.

Realization and Test of the Transport Layer Protocol (전달 계층 프로토콜 구현 및 시험에 관한 연구)

  • 전동근;차균현
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.18 no.5
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    • pp.650-662
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    • 1993
  • The thesis describes the realization and test of the transport layer operating on the CLNS (Connection Less Network Service) which is specified by ISO 8073 and ADDENDUM 2 protocol. For realization of the transport layer, five modules and interface primitives were definde. This protocol was formally described by SDL (Specification and Description Language) and was programmed in C-language. For verification of the software, protocol tester was implemented and test scenarios were defined. The verification was accomplished based on the test scenarios. Transport Layer software presented in this thesis may be utilized in a real situation with some modifications. Protocol tester presented in this thesis can also be used for verification of other protocol softwares.

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A Characteristics of Large Current and Minimum Quench Energy on Prototype High-$T_c$ Superconducting Cable (Prototype 고온초전도 케이블의 최소 Quench에너지 및 대전류 특성)

  • Kim, Sang-Hyun
    • Proceedings of the KIEE Conference
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    • 2000.11a
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    • pp.236-242
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    • 2000
  • NZP velocities were investigated on Ag sheathed multi filamentary Bi-2223 tape and direction type HTS cable. The critical current($I_c$) of Ag sheathed Bi-2223 tape and direction type HTS cable were 12 A, 63 A at 77 K, 0 T. NZP velocities of tape with two condition of DC and AC were almost same at each temperature. In case of DC, the NZP velocities of numerical analysis and experiment were almost same. NZP velocities of direction type HTS cable were 1.9-2.4 cm/sec. The result shows that the total transport current of spiral type HTS cable in $LN_2$ was 475[A], and transport current passed through almost the outer layer (2-layer). Also, AC transport losses in outer layer of HTS cable was proportion to $I^2$ and higher than losses of inner layer. And in case of $I_p=I_c$, calculated numerical loss density was concentrated on the edge of tape and most of loss density in cable was distributed outer layer more than inner layer.

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Analysis of Current Distribution of Multi-Layer HTSC Power Cable with a Shield Layer (차폐층을 갖는 다층고온초전도 전력케이블의 전류분류 분석)

  • Lee, Jong-Hwa;Lim, Sung-Hun;Ko, Seok-Cheol;Park, Chung-Ryul;Han, Byoung-Sung;Hwang, Si-Dole
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.07a
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    • pp.535-538
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    • 2004
  • Superconducting transmission power cable is one of interesting parts in power application using high temperature superconducting wire. One of important parameters in high-temperature superconduting (HTSC) cable design is transport current distribution because it is related with current transmission capacity and AC loss. In this paper, the transport current distribution at conducting layers was investigated through the analysis of the equivalent circuit for HTSC power cable with shield layer and compared with the case of without shield layer. The transport current distribution due to the pitch lenght was improved in the case of HTSC power cable with shield layer from the analysis.

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High performance of inverted polymer solar cells

  • Lee, Hsin-Ying;Lee, Ching-Ting;Huang, Hung-Lin
    • Proceedings of the Korean Vacuum Society Conference
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    • 2015.08a
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    • pp.61.2-61.2
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    • 2015
  • In the past decades, green energy, such as solar energy, wind power, hydropower, biomass energy, geothermal energy, and so on, has been widely investigated and developed to solve energy shortage. Recently, organic solar cells have attracted much attention, because they have many advantages, including low-cost, flexibility, light weight, and easy fabrication [1-3]. Organic solar cells are as a potential candidate of the next generation solar cells. In this abstract, to improve the power conversion efficiency and the stability, the inverted polymer solar cells with various structures were developed [4-6]. The novel cell structures included the P3HT:PCBM inverted polymer solar cells with AZO nanorods array, with pentacene-doped active layer, and with extra P3HT interfacial layer and PCBM interfacial layer. These three difference structures could respectively improve the performance of the P3HT:PCBM inverted polymer solar cells. For the inverted polymer solar cells with AZO nanorods array as the electronic transportation layer, by using the nanorod structure, the improvement of carrier collection and carrier extraction capabilities could be expected due to an increase in contact area between the nanorod array and the active layer. For the inverted polymer solar cells with pentacene-doped active layer, the hole-electron mobility in the active layer could be balanced by doping pentacene contents. The active layer with the balanced hole-electron mobility could reduce the carrier recombination in the active layers to enhance the photocurrent of the resulting inverted polymer solar cells. For the inverted polymer solar cells with extra P3HT and PCBM interfacial layers, the extra PCBM and P3HT interfacial layers could respectively improve the electron transport and hole transport. The extra PCBM interfacial layer served another function was that led more P3HT moving to the top side of the absorption layer, which reduced the non-continuous pathways of P3HT. It indicated that the recombination centers could be further reduced in the absorption layer. The extra P3HT interfacial layer could let the hole be more easily transported to the MoO3 hole transport layer. The high performance of the novel P3HT:PCBM inverted polymer solar cells with various structures were obtained.

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Implementation of NGN Service and Performance Measurement (NGN 서비스 구현과 성능측정)

  • Kim Hyoung-min;Kim Hwa-sung;Choi Young-il;Lee Byung-sun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.1B
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    • pp.1-6
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    • 2005
  • Communication network is in a transition toward the NGN (Next Generation Networks) to accommodate the explosive demand of new services. The NGN allows the third-party application provisioning by defining the networks as layers of Services, Distributed Processing Environment and Transport. Especially, the Service layer can further be divided into Application and Service Component layer. In order to realize the third-party application provisioning, the Parlay Group has adopted an open Parlay API as an interface between the Application and the Service Component layer. Using Parlay API, the third parties may develop and deploy the IT-based applications at the Application layer exploiting the service components located within network operators' domain. In this paper, we present the implementation details about the Third Party Call Control (TPCC) Service using the third-party service logic based on Parlay API and Parlay X API, when SIP is used as a signaling protocol in Transport layer. Also, we compare the performance evaluation of both implementations.

Quantum Dot Light-Emitting Diodes with Poly-TPD/PVK Bilayer Hole Transport Layer (Poly-TPD/PVK 이중 박막 정공수송층 구조의 양자점발광다이오드)

  • Kim, Hyun Soo;Lee, Do Hyung;Kim, Bada;Hwang, Bo Ram;Kim, Chang Kyo
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.32 no.5
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    • pp.393-398
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    • 2019
  • A poly[bis(4-butypheny)-bis(phenyl)benzidine] (poly-TPD) and poly(9-vinylcarbazole) (PVK) bilayer was employed as a hole transport layer (HTL) in solution-processed CdSe/ZnS quantum dot light-emitting diodes (QLEDs). The thickness of the PVK layer spin-coated onto the poly-TPD layer, whose thickness was fixed to 40 nm, was varied, with PVK layer thicknesses of 0 nm, 35 nm, 45 nm, and 55 nm. Because the thickness of the PVK can determine the hole transport properties of the HTL, a PVK thickness that maximizes the performance of the HTL for the QLEDs was investigated. By employing the optimized PVK thickness of 45 nm, the current efficiency of the QLED exhibited a 1.74 times improvement when compared with that of the QLED with poly-TPD based HTL without PVK. This was mainly attributed to the decrease in the energy barrier between the HTL and the quantum dot (QD) emitting layer (EML).

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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Design of Serial ATA Transport layer (직렬 ATA 전송층 설계)

  • 조은숙;박상봉;허정화
    • Proceedings of the IEEK Conference
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    • 2003.11c
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    • pp.365-368
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    • 2003
  • In this Paper, we report a design of Serial ATA Transpor layer. The functionalities of the Serial ATA transport layer are first described on RTL via verilog. The compiled code are then fed to a synthesizer synopsys to get the actual hardware from 0.35$\mu\textrm{m}$ SAMSUNG standard cell library. The designed functionalities of this chip will be verified using test bold with FPGA equipment and ATS2 digital test equipment.

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Theoretical Analysis of Heat Transport Limitation in a Screen Mesh Wick Heat Pipe

  • Lee, Ki-Woo;Park, Ki-Ho;Lee, Wook-Hyun;Rhi, Seok-Ho
    • International Journal of Air-Conditioning and Refrigeration
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    • v.12 no.1
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    • pp.1-9
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    • 2004
  • The purpose of the present study is to examine the heat transport limitations in a screen mesh heat pipe for electronic cooling by theoretical analysis. Diameter of pipe was 6mm, and mesh numbers were 50, 100, 150, 200 and 250, and water was investigated as working fluid. According to the change of mesh number, wick layer, inclination and saturation temperature, the maximum heat transport limitations by capillary, entraintment, sonic and boiling were analyzed by a theoretical design method of heat pipe, including capillary pressure, pumping pressure, liquid friction coefficient in wick, vapor friction coefficient, etc. Based on the results, the capillary limitation in a small diameter of heat pipe is largely affected by mesh number and wick layer. Mesh number of 250 is desirable not to be used in pipe diameter of 6 mm, because capillary heat transport limitation decreases by the abrupt increase of liquid friction pressure due to the small liquid flow area. For the heat transport of 15 watt in 6mm diameter pipe, mesh number of 100 and one layer is an optimum wick condition, which thermal resistance is the smallest.