• Title/Summary/Keyword: S-Buffer

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A Shared Buffer-Constrained Topology Reconfiguration Scheme in Wavelength Routed Networks

  • Youn, Chan-Hyun;Song, Hye-Won;Keum, Ji-Eun
    • ETRI Journal
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    • v.27 no.6
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    • pp.725-732
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    • 2005
  • The reconfiguration management scheme changes a logical topology in response to changing traffic patterns in the higher layer of a network or the congestion level on the logical topology. In this paper, we formulate a reconfiguration scheme with a shared buffer-constrained cost model based on required quality-of-service (QoS) constraints, reconfiguration penalty cost, and buffer gain cost through traffic aggregation. The proposed scheme maximizes the derived expected reward-cost function as well as guarantees the required flow's QoS. Simulation results show that our reconfiguration scheme significantly outperforms the conventional one, while the required physical resources are limited.

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Circle calibration distorted by camera lense (렌즈에 의해 왜곡된 원영상의 교정)

  • 최춘호;문철홍
    • Proceedings of the IEEK Conference
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    • 1998.06a
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    • pp.721-724
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    • 1998
  • A circular image in a space don't appear as an exact circular image and appear as an oval in image buffer because distortion of camera lens, number of horizontal pixel of CCD photographing element and unmber of horizontal pixel of image buffer are not in accordance. By using familiar 3-D coordinate, know as circle's diameter, and cicle's center, you correct a pin-hole camera and get an exact circle with reprojection a circle into image buffer, according to a perspective.

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A Study of Buffer Allocation in FMS based on Deadlock & Workload (FMS의 Deadlock과 Workload를 고려한 최적 버퍼 할당에 관한 연구)

  • 이정표;김경섭
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2000.10a
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    • pp.71-74
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    • 2000
  • Due to the complexity of parts flow and limited resources, FMS(Flexible Manufacturing System) develops blocking, starvation and deadlock problems, which reduce its performance. In order to minimize such problems buffers are imposed between workstations of the manufacturing lines. In this paper, we are concerned with finding the optimal buffer allocation with regard to maximizing system throughput in limited total buffer capacity situation of FMS. A grouping heuristic to solve the buffer allocation problem is proposed. Computer simulation using Arena will be experimented to show the validation of the proposed algotithm.

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Adaptive Buffer Management Method for Quality of Service of Internet Telephony (인터넷폰의 QoS를 위한 적응적인 버퍼관리 방식)

  • 류태욱;이정훈;강성호;엄기환
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.6 no.3
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    • pp.386-392
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    • 2002
  • Internet telephony is an application that transmits voice data for conversation. Therefore it must provide high sound quality. However while audio packets are transferred through the network, they are affected by delay variations and jitters, which could result in poor sound quality of the receiving end does not have an appropriate jitter buffer to overcome network factors. This thesis introduces a buffer management algorithm that could be used to provide better sound quality for Internet phone terminals. This algorithm actively responds to both the compression algorithms that are used by the terminals, as well as to the received data to provide an improvement in sound quality. In order to verify the effectiveness of the proposed algorithm, we experimented in variance network settings. The results show that the proposed algorithm improves on the performance of the conventional buffer management algorithm.

Effect of Sodium Malate Buffer as pH Adjuster on the Fermentation of Kimchi (pH조정제 Sodium Malate Buffer의 첨가가 김치의 숙성에 미치는 효과)

  • Kim, Soon-Dong;Lee, Shin-Ho
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.17 no.4
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    • pp.358-364
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    • 1988
  • The effect of sodium malate buffer(SMB) on the fermentation of Kimchi was investigated. Chemical and microbial changes were investigated during fermentation of Kimchi containing 0,2,4 and 6% salt at $25^{\circ}C$. The fermentaton of lower salted Kimchi was taster than that of higher salted Kimchi. One percent addition of SMB, as pH adjuster, showed the retardation of Kimchi fermentation about 36 hours at $25^{\circ}C$. Due to the buffer action of SMB, the acidity was inclosed during the fermentation as concentration of SMB increased. The buffer action of SMB was increased during fermentation of Kimchi.

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Application of Buffer Layers for Back Contact in CdTe Thin Film Solar Cells

  • Chun, Seungju;Kim, Soo Min;Lee, Seunghun;Yang, Gwangseok;Kim, Jihyun;Kim, Donghwan
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.318.2-318.2
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    • 2014
  • The high contact resistance is still one of the major issues to be resolved in CdS/CdTe thin film solar cells. CdTe/Metal Schottky contact induced a high contact resistance in CdS/CdTe solar cells. It has been reported that the work function of CdTe thin film is more than 5.7 eV. There has not been a suitable back contact metal, because CdTe thin film has a high work function. In a few decades, some buffer layer was reported to improve a back contact problem. Buffer layers which are Te, $Sb_2Te_3$, $Cu_2Te$, ZnTe:Cu and so on was inserted between CdTe and metal electrode. A formed buffer layers made a tunnel junction. Hole carriers which was excited in CdTe film by light absorption was transported from CdTe to back metal electrode. In this report, we reported the variation of solar cell performance with different buffer layer at the back contact of CdTe thin film solar cell.

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The ZnS Film Deposition Technology for Cd-free Buffer Layer in CIGS Solar Cells

  • Lee, Jae-Hee;Hwang, Do-Weon
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.08a
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    • pp.218-218
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    • 2011
  • The CIGS Solar Cells have the highest conversion efficiency in the film-type solar cells. They consist of p-type CuInSe2 film and n-type ZnO film. The CdS films are used as buffer layer in the CIGS solar cells since remarkable difference in the lattice constant and energy band gap of two films. The CdS films are toxic and make harmful circumstances. The CdS films deposition process need wet process. In this works, we design and make the hitter and lamp reflection part in the sputtering system for the ZnS films deposition as buffer layer, not using wet process. Film thickness, SEM, and AFM are measured for the uniformity valuation of the ZnS films. We conclude the optimum deposition temperature for the films uniformity less than 1.6%. The ZnS films deposited by the sputtering system are more dense and uniform than the CdS films deposited by the Chemical Bath Deposition Method(CBD) for the CIGS Solar Cells.

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A TCP Fairness Improvement Scheme for Wired and Wireless Heterogeneous Networks (유무선 혼합 네트워크에서의 TCP Fairness 향상 기법)

  • Cho, Sung-Joon;Kim, Seong-Chul
    • Journal of Advanced Navigation Technology
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    • v.10 no.1
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    • pp.34-40
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    • 2006
  • Multiple wireless devices in wired and wireless heterogeneous networks communicate with counterparts via a single Access Point (AP). In this case, the AP becomes a bottleneck of the network, therefore buffer overflows occur frequently and result in TCP performance degradation. In this paper, the new algorithm that prevents buffer overflows at AP and enhances TCP fairness is proposed. Depending on the buffer usage of AP, the new algorithm adaptively controls each TCP senders' transmission rate, prevents buffer overflows and thus guarantees improved TCP fairness. It is proved that the algorithm makes better of TCP throughput and fairness by preventing buffer overflows.

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