• Title/Summary/Keyword: Transport mode

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The Design and Implementation of the SRTPIO Module for a Real-time Multimedia Data Transport (실시간 멀티미디어 데이타 전송을 위한 SRTPIO 모듈 설계 및 구현)

  • Nam, Sang-Jun;Lee, Byung-Rae;Kim, Tai-Woo;Kim, Tai-Yun
    • Journal of KIISE:Information Networking
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    • v.28 no.4
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    • pp.621-630
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    • 2001
  • Recently, users' demands for multimedia service are increasing. But, server systems offer inefficient multimedia data service to users. In this paper, to transport multimedia data in the server system more efficiently, we propose the SRTPIO(Special RTP Input/Output) module that process the RTP(Real-time Transport Protocol) data in the kernel with the SIO(Special Input/Output) Mechanism. The SIO mechanism improve a transfer speed because it reduces overheads associated with data copying and context-switching between the user mode and the kernel mode occured in general server system in the kernel-level. The SRTPIO module, integrating the SIO mechanism and the RTP data processing in the kernel, support efficient multimedia data transfer architecture.

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An Analysis of the Importance of Accessibility for High Speed Railway : Stated-Preference Approach (고속철도에 있어서 접근도의 중요성 분석에 관한 연구)

  • Park, D.R.;Nam, K.C.
    • Journal of Korean Port Research
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    • v.8 no.1
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    • pp.49-63
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    • 1994
  • The introduction of high speed railway system a significant impact on the conventional inter-urban transport systems by inducing a significant traffic from the existing modes as well as generating a new traffic. It is also closely related to intra-urban transport systems as the inter-urban traffic has its origin and destination in a city. In the context of mode choice, for high speed transport systems, it has been argued that the accessibility is the most important attribute conceived by users. Thus this study attempts to analysis the importance of the accessibility for the planned high speed railway systems particularly with respect to the location of Busan Station. For this Stated-Preference approach, which is considered appropriate for such study, is adopted, and disaggregate binary logit models for mode choice between the high speed railway and air service in Busan-Seoul corridor are developed. The elasticities for cost and service variables are also derived. The results disclose that cost is the most important which is inconsistent with most previous studies ; accessibility has considerable impact on the choice ; and frequency however has a little impacts. Concerning location of the high speed railway station the results suggest that the longer the access distance is, the more important the accessibility is. This implies that the connection of reliable access transport services such as underground are essential between the terminal and urban center.

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A Mathematical Model Development for the Nitrification-Denitrification Coupled Process

  • ;;T. Prabhakar Clement
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2003.04a
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    • pp.430-433
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    • 2003
  • Nitrogen pollution in urban and rural groundwater is a common problem and poses a major threat to drinking water supplies based on groundwater. In this work, the kinetics of nitrification-denitrification coupled reactions are modeled and new reaction modules for the RT3D code describing the fate and transport of nitrogen species, dissolved oxygen, dissolved organic carbon, and biomass are developed and tested. The proposed nitrogen transformations and transport model showed very good match with the results of other public codes.

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Simulation of Submicron MOSFET Using Hydrodynamic Model (Hydrodynamic model을 이용한 Submicron MOSFET의 Simulation)

  • 김충원;한백형;김경석
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.30A no.11
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    • pp.122-131
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    • 1993
  • In this paper, we have developed a submicron Si MOSFET simulator, which is physically based on the hydrodynamic energy transport mode. The simulator was used to investigate the nonstationary transport effects and the transient phenomena in submicron Si MOSFET's. It is found that the velocity overshoot and the carrier heating are dominant transport mechanism near the drain end of the channel and the transient phenomena is more retained in a long channel MOSFET.

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Design and Implementation of Travel Mode Choice Model Using the Bayesian Networks of Data Mining (데이터마이닝의 베이지안 망 기법을 이용한 교통수단선택 모형의 설계 및 구축)

  • Kim, Hyun-Gi;Kim, Kang-Soo;Lee, Sang-Min
    • Journal of Korean Society of Transportation
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    • v.22 no.2 s.73
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    • pp.77-86
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    • 2004
  • In this study, we applied the Bayesian Network for the case of the mode choice models using the Seoul metropolitan area's house trip survey Data. Sex and age were used lot the independent variables for the explanation or the mode choice, and the relationships between the mode choice and the travellers' social characteristics were identified by the Bayesian Network. Furthermore, trip and mode's characteristics such as time and fare were also used for independent variables and the mode choice models were developed. It was found that the Bayesian Network were useful tool to overcome the problems which were in the traditional mode choice models. In particular, the various transport policies could be evaluated in the very short time by the established relation-ships. It is expected that the Bayesian Network will be utilized as the important tools for the transport analysis.

Generic studies on thermo-solutal convection of mercurous chloride system of ${Hg_2}{Cl_2}$ and Ne during physical vapor transport

  • Choi, Jeong-Gil;Lee, Kyong-Hwan;Kim, Geug-Tae
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.19 no.1
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    • pp.39-47
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    • 2009
  • The effects of thermo-solutal convection on mercurous chloride system of ${Hg_2}{Cl_2}$, and Ne during physical vapor transport are numerically investigated for further understanding and insight into essence of transport phenomena, For $10\;K{\le}{\Delta}T{\le}30\;K$, the growth rate slowly increases and, then is decreased gradually until ${\Delta}T$=50 K, The occurrence of this critical point near at ${\Delta}T$=30 K is likely to be due to the effects of thermo-physical properties stronger than the temperature gradient corresponding to driving force for thermal convection. For the range of $10\;Torr{\le}P_B{\le}300\;Torr$, the rate is second order-exponentially decayed with partial pressures of component B, $P_B$. For the range of $5{\le}M_B{\le}200$, the rate is second order-exponentially decayed with a function of molecular weight of component B, $M_B$. Like the case of a partial pressure of component B, the effects of a molecular weight arc: reflected through the binary diffusivity coefficients, which are intimately related with suppressing the convection flow inside the growth enclosure, i,e., transition from convection to diffusion-dominant flow mode as the molecular weight of B increases. The convective mode is near at a ground level, i,e., on earth (1 $g_0$), and the convection is switched to the diffusion mode for $0.1\;g_0{\le}g{\le}10^{-2}g_0$, whereas the diffusion region ranges from $10^{-2}g_0$ up to $10^{-5}g_0$.

Interpretation of Permeation Characteristics and Membrane Transport Models Through Polyamide Reverse Osmosis Membrane (Polyamide 역삼투막의 투과성능과 막 이동 모델의 해석)

  • 김노원;김영길;이용택
    • Membrane Journal
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    • v.14 no.1
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    • pp.75-84
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    • 2004
  • In this study, we present a noble study far membrane transport models using chlorine resistance of polyamide RO membranes. Membrane transport mechanism is investigated by the comparison of membrane permeation performance under the continuous and Intermittent operation modes with mixed feed solution containing NaOCl and NaCl. Analysis of permeation performance indicates that solution-diffusion model and preferential adsorption-capillary flow model are relatively efficient according to operation mode. Under the continuous flow state, mass transfer depends on preferential adsorption-capillary flow model rather than solution-diffusion model. On the other hand, it prefers solution-diffusion model to preferential adsorption-capillary flow model under the stationary state. SEM images of NaOCl treated membrane surfaces strongly support these conclusions. These surface images reveal that NaOCl treated membrane in continuous operation mode exhibits ridge and valley structure in some fraction of the surface area, whereas that in intermittent operation mode shows surface degradation entirely.

Performance Comparison of ISO / IEC 18000-3 ASK and PJM Mode (ISO/IEC 18000-3 ASK 모드와 PJM 모드의 성능 비교)

  • Kim, Jae-Lim;Yang, Hoon-Gee
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.7 no.6
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    • pp.70-80
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    • 2008
  • This paper presents comparison of 18000-3 ASK and PJM mode RFID in terms of reading speed. This is accomplished by counting the occurrences of a few representative blocks which constitute the reader / tag interactions for each mode. To apply FS (frame slotted)-aloha protocol, four Q-algorithms, which are a Q-algorithm suggested in the standard document, a fixed Q-algorithm, a minimum Q-algorithm and the number of tag dependent Q-algorithm, are used. Through some simulations, we present the reading speed of each mode with respect to the Q-algorithm and the comparison of the reading speed between the two modes for each Q-algorithms.

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