• Title/Summary/Keyword: Protocol Data Unit

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A LAN System Based on the Buffer Insertion Protocol (버퍼 삽입 프로토콜에 의한 LAN시스템에 관한 연구)

  • 권영수;강창언
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.11 no.1
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    • pp.16-24
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    • 1986
  • The queueing delay and the response time of model of the buffer insertion LAN have been derived and its performance has been analyzed in terms of the throughput rate-response time characteristic. The results show that the response time can be improved by increasing the medium data rate, and that it can be reduced by 0.7 msec by transmitting the acknowledgement signal at the network interface unit(NIU) rather than at the hose, when the channel utilization is approximately 0.8. Also, implementation of the buffer insertion protocol has been studied.

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Modeling and Simulation of a RAID System (RAID 시스템의 모델링 및 시뮬레이션)

  • 이찬수;성영락;오하령
    • Proceedings of the Korea Society for Simulation Conference
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    • 2001.05a
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    • pp.77-81
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    • 2001
  • In this paper, a RAID system is modeled and simulated by using the DEVS formalism. The RA[D system interacts with a host system by using the high-speed Fibre channel protocol and stores input data in an array of IDE disks. The DEVS formalism specifies discrete event systems in a hierarchical, modular manner. The RAID system model is composed of three units: primary-PCI unit, secondary-PCI unit and CPU unit. The primary-PCI unit interfaces with the host system and caches I/O data. The secondary-PCI unit includes disks. The CPU unit controls overall system. The control algorithm of CPU and PCI transactions are analyzed and modeled. From an analysis of simulation events, we can conclude that the proposed model satisfies given requirements.

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Modeling and Simulation of a RAID System (RAID 시스템의 모델링 및 시뮬레이션)

  • 이찬수;성영락;오하령
    • Journal of the Korea Society for Simulation
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    • v.11 no.1
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    • pp.11-22
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    • 2002
  • In this paper, a RAID system is modeled and simulated by using the DEVS formalism. The RAID system interacts with a host system by using the high-speed Fibre channel protocol and stores data in an array of IDE disks. The DAVS formalism specifies discrete event systems in a hierarchical, modular manner. The RAID system model is composed of three units: primary-PCI unit, secondary-PCI unit and MCU unit. The primary-PCI unit interfaces with the host system and I/O data caches. The secondary-PCI unit includes disks. The MCU unit controls overall system. The control algorithm of MCU and PCI transactions are analyzed and modeled, From the analysis of simulation events, we can conclude that the proposed model satisfies given requirements.

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A Study on Implementation of IRIG-B Protocol for Time Synchronization of IEC 61850 based Merging Unit (IEC 61850 기반 병합단위장치의 시간 동기화를 위한 IRIG-B 프로토콜 구현에 관한 연구)

  • Kim, Gwan-Su;Lee, Hong-Hee;Kim, Byung-Jin
    • The Transactions of the Korean Institute of Power Electronics
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    • v.13 no.4
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    • pp.303-310
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    • 2008
  • Recently, IEC 61850 supports the standardized communication technique in both station bus and process bus, and presents substation automation model. In order to implement the IEC 61850 based communication in a substation using the MU (merging unit) which is one of the important data acquisition equipments in substation automation, the time synchronization is demanded for cooperative operation between the devices. This paper proposes the precision time synchronization technique using IRIG-B protocol to develop the MU under IEC 61850 communication protocol. The proposed technique is implemented and its performance is verified experimentally.

Using OBD2 protocol, A implement of blackbox with vehicle state data and the external video (OBD프로토콜의 차량 주행 데이터와 외부 영상을 이용한 블랙 박스 구현)

  • Back, Sung-Hyun;Jang, Jong-Wook
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2010.05a
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    • pp.97-100
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    • 2010
  • Lately, becausing Life, property loss from car accident, vehicles have been used vehicle blackbox like blackbox by airplane. when the accident happened, existing car blackbox that was stored external image or video of vehicle don't know the vehicle's driving conditions. For knowing vehicle's driving conditions, vehicle is loaded sensors for Variety of measurement and control. the sensors is controlled by ECU(Electronic Control Unit) and all vehicles is used Mandatory OBD2(On-board diagnostics) protocol for communication between ECUs since 2006. Using ODB2 protocol, driver use blackbox data by various driving data to occur vehicle' ECU and can be obtained more definitive information. In this paper, there implement smart blackbox system to use exact vehicle's data using OBD2 protocol rather than blackbox to store external image or video.

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A MAS Information Management Method for WiMedia MAC Protocol

  • Chung, Tae-Wook;Chung, Chul-Ho;Kim, Jae-Seok
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.9 no.4
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    • pp.205-208
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    • 2009
  • In this paper, a MAS information management method is proposed for the WiMedia MAC protocol. WiMedia MAC configures a fully distributed network based on Ad-hoc method. WiMedia devices communicate during Superframe which is a communication unit in WiMedia MAC. Each superframe which consist of 256 MASs is divided into two periods, beacon period and data period. In data period, devices communicate with each other using the received channel access information during the beacon period. Due to only $12{\mu}s$ timing allowance between beacon period and data period, the process of the MAS information management cannot be completed in time if entire process handle by software. Therefore, we propose a novel MAS information management method using hardware module. With our proposed method, a WiMedia device is satisfied with the processing time that is required in WiMedia MAC protocol.

Development and Implementation of a Feeding Protocol for Infants in a Pediatric Cardiac Intensive Care Unit (소아심장외과 중환자실 장관영양 프로토콜 개발 및 효과평가)

  • Uhm, Ju-Yeon;Lee, Hyojin
    • Child Health Nursing Research
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    • v.22 no.4
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    • pp.326-335
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    • 2016
  • Purpose: It is crucial to provide adequate enteral nutrition for postoperative recovery, wound healing and normal growth in infants in pediatric cardiac ICUs. This study was done to develop a feeding protocol using the vaso-active inotropic (VAI) score and to evaluate the impact of nutritional outcomes following the new feeding protocol for infants who underwent cardiac surgery. Methods: This study consisted of three phases. First, a feeding protocol was developed based on a literature review. Second, ten experts rated the content validity. Third, a comparison study was conducted to evaluate the impact of the new feeding protocol. Data were analyzed using SPSS Version 20. Results: Twenty-nine infants were enrolled in the pre-protocol group, and 22 infants in the post-protocol group. Patients in the 2 groups were similar. Time to reach feeding goal was significantly decreased from 56.0 (27-210) hours to 28.5 (10-496) hours in the post-protocol group (Z=-4.22, p<.001). Level of enteral feeding knowledge among nurses increased significantly after implementation of the protocol. Conclusion: The feeding protocol using VAI score facilitates the achievement feeding goal to decrease feeding interruptions and help nurses in their practice. Larger studies are necessary to examine clinical outcomes following the implementation of this feeding protocol.

A Simulation of Bridge using the Spanning Tree Protocol (스패닝 트리 프로토콜을 이용한 브릿지 시뮬레이션)

  • Lee, Sook-Young;Lee, Eun-Wha;Lee, Mee-Jeong;Chae, Ki-Joon;Choi, Kil-Young;Kang, Hun
    • Journal of the Korea Society for Simulation
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    • v.6 no.2
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    • pp.45-57
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    • 1997
  • MAC (media access control) bridge is used to interconnect separate LANs and to relay frames between the BLANs (bridged LANs). Bridge architecture consists of MAC entity, MAC relay entity and bridge protocol entity protocol entity and performs learning, filtering and forwarding functions using filtering database. In this paper, we simulate these functions of bridge and the STP (spanning tree protocol). The STP derives an active topology from an arbitrarily connected BLAN. Our simulation model assumes a BLAN consisted of three bridge forming a closed loop. In order to remove the loop, each bridge process exchanges configruation BPDU (bridge protocol data unit0 with other bridge processes connected to the bridge itself. To simulate the communication between bridges, we implement the IPC (inter-process communication) server using message queues. Our simulation results show that the assumed BLAN contains no closed loop and then there is no alternative route and no unnecessary traffic.

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The MS Card Data Transfer System using Bluetooth Protocol (블루투스를 이용한 마그네틱 카드 정보 전송 시스템)

  • 강형원;김영길
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2003.05a
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    • pp.435-438
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    • 2003
  • The MS card data transfer system using blue-tooth protocol ran communicate the MS card data wirelessly and does not take an extra communication expense which is a weakness point of existing wireless communication system. This Blue-tooth system, which has excellent security and no extra communication expense, can efficiently communicate data of the place ,where can be solved with small scale wireless network, such as the theme-park or gasoline-station. Existing wireless communication system compose network using wireless-LAN protocol which has extra communication expense, or with RF protocol which has poor security. But this system suitable for LAN because it has not extra communication expense and it has excellent security cause frequency-hopping of Blue-tooth protocol. The MS card data transfer system using blue-tooth protocol has low power, high performance RISC processor and large scale 16-gray graphic LCD which is suitable for portable unit. The MS card data transfer system can efficiently control depot for a long time because it has low power, excellent security and no extra communication expense.

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Evaluation of Clinical Alarms and Alarm Management in Intensive Care Units (중환자실에서 사용되는 의료장비의 경보음 발생과 관리 현황)

  • Jeong, Yu Jin;Kim, Hyunjung
    • Journal of Korean Biological Nursing Science
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    • v.20 no.4
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    • pp.228-235
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    • 2018
  • Purpose: This study aimed to investigate the clinical alarm occurrence and management of nurses toward clinical alarms in the intensive care unit (ICU). Methods: This observational study was conducted with 40 patients and nurses cases in two ICUs of a university hospital. This study divided 24 hours into the unit of an hour and conducted two times of direct observation per unit hour for 48 hours targeting the medical devices applied to 40 patients. Data were analyzed using IBM SPSS Statistics 23. Results: On average, 3.8 units of medical devices were applied for each patient and the ranges of alarm settings were wide. During 48 hours, 184 cases of clinical alarm were occurred by four types of medical devices including physiological monitors, mechanical ventilators, infusion pumps, and continuous renal replacement therapy. Among them, false alarm was 110 cases (59.8%). As for the alarm management by ICU nurses, two-minute alarm mute took up most at 38.0% (70 cases), and no response was second most at 32.6% (60 cases). When valid alarm sounded, nurses showed no response at 43.2%. Conclusion: The findings suggest that a standard protocol for alarm management should be developed for Korean ICU settings. Based on the protocol, continuous training and education should be provided to nurses for appropriate alarm management.