• Title/Summary/Keyword: Probing Mechanism

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A Study on Probing based Multicasting Admission Control Mechanism for IP Multimedia Service (IP 멀티미디어 서비스를 위한 Probing 기반 멀티캐스팅 수락 제어 메커니즘 연구)

  • Rhee, Woo-Seop;Yoo, Whan-Seok;Lee, Soon-Seok
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.10B
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    • pp.613-620
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    • 2007
  • Recently, due to the developing of broadband convergence networks, the high quality multimedia services which are converged with communication and broadcasting can be provided. These high quality communication and broadcasting convergence service needs reliable multicasting mechanism in IP networks. However, multicasting mechanism recently deployed is difficult to guarantee the end-to-end QoS. For the reliable high quality If multimedia IPTV service, the QoS guaranteed multicasting mechanism should be provided. Therefore, we proposed a probing packet based multicasting admission control mechanism using centralized multicasting control management block in this paper. And for the performance evaluation of the proposed mechanism, we used ns-2 simulator.

SACK TCP with Probing Device

  • Liang, Bing;Hong, Choong Seon
    • Proceedings of the Korea Information Processing Society Conference
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    • 2004.05a
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    • pp.1355-1358
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    • 2004
  • This paper describes a modification to the SACK (Selective Acknowledgement) Transmission Control Protocol's (TCP), called SACK TCP with Probing Device, SACK works in conjunction with Probing Device, for improving SACK TCP performance when more than half a window of data lost that is typical in handoff as well as unreliable media. It shows that by slightly modifying the congestion control mechanism of the SACK TCP, it can be made to better performance to multiple packets lost from one window of data.

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The QoS guaranteed seamless mobile multicast handover mechanism using probing based CAC and PMIPv6 (Probing 기반 수락제어와 PMIPv6를 이용한 품질보장 Seamless 모바일 멀티캐스트 핸드오버 메커니즘)

  • Kang, Hyun-Myoung;Choi, Hoan-Suk;Rhee, Woo-Seop
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.7B
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    • pp.1018-1033
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    • 2010
  • Recently, as the use of mobile terminal is generalized, the needs of high-speed Internet mobile service is increased. Also users want to receive the multimedia contents what they want through the various terminals in anywhere, anytime via wired and wireless integrated environment. Therefore, various mechanisms that support the mobility are proposed. However, these mechanisms are difficult to support seamless mobility and QoS awareness on the mobile multicast environment. In this paper, we propose a QoS aware handover mechanism that is able to provide the high-quality and real-time services such as mobile IPTV in an integrated environment for these requests of users. Proposed mechanism manages the multicast admission control and multicast handover using the 2-layer multicast information management at the wired and wireless integrated network that extended the service guaranteed methods through the probing based admission control of the wired network to the wireless network based on PMIPv6. We present a performance evaluation results and features analyzed by the simulations using the ㎱-2.

Touch-Trigger Probe Error Compensation in a Machining Center (공작기계용 접촉식 측정 프로브의 프로빙 오차 보상에 관한 연구)

  • Lee, Chan-Ho;Lee, Eung-Suk
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.35 no.6
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    • pp.661-667
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    • 2011
  • Kinematic contact trigger probes are widely used for feature inspection and measurement on coordinate measurement machines (CMMs) and computer numerically controlled (CNC) machine tools. Recently, the probing accuracy has become one of the most important factors in the improvement of product quality, as the accuracy of such machining centers and measuring machines is increasing. Although high-accuracy probes using strain gauge can achieve this requirement, in this paper we study the universal economic kinematic contact probe to prove its probing mechanism and errors, and to try to make the best use of its performance. Stylus-ball-radius and center-alignment errors are proved, and the probing error mechanism on the 3D measuring coordinate is analyzed using numerical expressions. Macro algorithms are developed for the compensation of these errors, and actual tests and verifications are performed with a kinematic contact trigger probe and reference sphere on a CNC machine tool.

Contact Probing Technique for Profile Measurement of Aspheric Lenses (비구면 렌즈의 형상 측정을 위한 접촉식 프로브 기술 개발)

  • 유승봉;장인철;김승우
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2000.05a
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    • pp.603-606
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    • 2000
  • This dissertation is concerned with ultra-precision profile measurement of aspheric surfaces using contact probing technique. A contact probe has been designed as a sensing device to obtain measuring resolutions in nanometer regime utilizing a leaf spring mechanism and a capacitive-type sensor. The contact probe is attached on the z-axis during measurement while aspheric objects are supported on an precision xy-stage whose lateral motions are monitored by a set of two orthogonal plane mirror type laser interferometers. Experimental results show that the contact probing technique developed in this investigation is capable of providing a repeatability of 50 nanometers with a $\pm$3$\sigma$ uncertainty of 300 nanometers. Thermal disturbance is found the most significant factor that should be precisely controlled for accurate measurement.

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A study on Ultra Precision machining process for Aspheric (비구면 초정밀절삭 공정기술에 관한 연구)

  • 김건희;홍권희;김효식;김현배;양순철;윈종호
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2003.06a
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    • pp.90-93
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    • 2003
  • This paper described about the ultra-precision profile measurement of aspheric surfaces using contact probing technique. A contact probe has been designed as a sensing device to obtain measuring resolutions in nanometer regime utilizing a circle leaf spring mechanism and a capacitive-type sensor. The, contact probe is attached on the z-axis during measurement while aspheric object are supported on the diamond turning machine(DTM). The machine xz-axis motions are monitored by a set of two orthogonal plane mirror type laser interferometers. Experimental results show that the contact probing technique developed of on-machine measurement system in this investigation is capable of providing a repeatability of 10 nanometers with a $\pm$20 uncertainty of 200nmPv.

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Development of On-machine Measurement System utilizing a Capacitive-type Sensor (정전용량형 센서를 이용한 기상계측시스템의 개발)

  • 김건희;박순섭;박원규;원종호
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.10a
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    • pp.391-395
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    • 2002
  • This paper described about the ultra-precision profile measurement of aspheric surfaces using contact probing technique. A contact probe has been designed as a sensing device to obtain measuring resolutions in nanometer regime utilizing a leaf spring mechanism and a capacitive-type sensor. The contact probe is attached on the z-axis during measurement while aspheric objects are supported on the single point diamond turning machine(SPDTM). The machine xz-axis motions are monitored by a set of two orthogonal plane mirror type laser interferometers. Experimental results show that the contact probing technique developed of On-machine Measurement System in this investigation is capable of providing a repeatability of 20 nanometers with a $\pm$20 uncertainty of 300 nanometers.

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An Adaptive Feedback Rate Control Algorithm for Unicast Video Transmission

  • Ru, Zhou;Jang, Kyung-Sik
    • Proceedings of the Korea Information Processing Society Conference
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    • 2007.11a
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    • pp.966-969
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    • 2007
  • In this paper, we propose a novel probing mechanism for adaptive transmission of video data based on congestion control and client state. The proposed mechanism is friendly to the network dominant transport protocols (TCP) and can reduce fluctuations compared to the previous works.

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Anti-inflammatory Action of Calorie Restriction for Life-Prolongation: A Possible Mechanism

  • Chung, Hae-Young
    • Proceedings of the PSK Conference
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    • 2002.10a
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    • pp.173-174
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    • 2002
  • Oxidative modification of cellular structures and functions by redox imbalance is the basis of the current oxidative stress hypothesis of aging. The experimental support for this hypothsis has been generated from recent molecular probing on the interrelation between the age-related functional impairments and the pathogenesis. (omitted)

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A variably compliable probe system for the in-circuit test of a PCB (인쇄회로기판의 통전검사를 위한 가변순응력을 갖는 프로브 시스템)

  • Shim, Jae-Hong;Cho, Hyung-Suck;Kim, Sung-Kwun
    • Journal of Institute of Control, Robotics and Systems
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    • v.3 no.3
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    • pp.323-331
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    • 1997
  • A new probing mechanism and an active compliance control algorithm have been developed for the in-circuit test of a PCB( printed circuit board ). Commercially available robotic probing devices are incapable of controlling contact force generated through rigid probe contacts with a solder joint, at high speed. The uncontrollable excessive contact force often brungs about some defects on the surface of the solder joint, which is plastically deformable over some limited contact force. This force also makes unstable contact motions resulting in unreliable test data. To overcome these problems, we propose that a serially connected macro and micro device with active compliance provide the best potential for a safe and reliable in-circuit test. This paper describes the design characteristics, modeling and control scheme of the newly proposed device. The experimental results clearly show the effectiveness of the proposed system.

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