• Title/Summary/Keyword: Coordinator

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Design of a Fault-Tolerant System Using Dynamic Coordinator-Based Active Replication (동적 코디네이터 기반의 능동형 복제를 통한 결함허용 시스템 설계)

  • You, Seung-Duk;Lee, In-Hwan
    • Proceedings of the Korea Information Processing Society Conference
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    • 2005.11a
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    • pp.791-794
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    • 2005
  • 본 논문에서는 인터넷 기반의 예약 시스템 설계시 가용성(Availability)을 높이기 위해 능동형 레플리케이션(Active Replication)기법을 이용하였으며 서비스 요청에 대한 응답지연 시간을 줄이고자 레플리케이션 그룹 내에 동적 코디네이터(Dynamic Coordinator)를 이용하였다. 실험 결과는 코디네이터을 사용하였을 경우 33% 빠른 응답속도를 보였다. 그러나 코디네이터 선출 방식을 동적으로 하였을 경우 코디네이터 선출시 사용되는 많은 메시지로 인하여 79.98% 증가된 지연시간을 확인하였다.

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Secure IEEE 802.15.4 Join Protocol for 6LoWPAN (6LowPAN 환경에서의 안전한 IEEE 802.15.4 가입 프로토콜)

  • Ahn, Seung-Hyun;Park, Chang-Seop;Yeon, Han-Beol
    • Convergence Security Journal
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    • v.15 no.7
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    • pp.103-110
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    • 2015
  • The security of the data exchanged between sensor nodes in IoT (Internet of Things) environment becomes increasing. In the conventional IEEE 802.15.4, the key for secure communication between the sensor node and the sensor node and the PAN Coordinator or the sensor node is assumed to be pre-shared in advance. Especially, there is another problem in that sensor node authentication is not considered during the association process. In this paper, we propose a security scheme that solves the problems of previously proposed protocols with the pre-shared key for all devices.

Predicting Nonlinear Processes for Manufacturing Automation: Case Study through a Robotic Application

  • Kim, Steven H.;Oh, Heung-Sik
    • Journal of Korean Institute of Industrial Engineers
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    • v.23 no.2
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    • pp.249-260
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    • 1997
  • The manufacturing environment is rife with nonlinear processes. In this context, an intelligent production controller should be able to predict the dynamic behavior of various subsystems as they react to transient environmental conditions, the varying internal condition of the manufacturing plant, and the changing demands of the production schedule. This level of adaptive capability may be achieved through a coherent methodology for a learning coordinator to predict nonlinear and stochastic processes. The system is to serve as a real time, online supervisor for routine activities as well as exceptional conditions such as damage, failure, or other anomalies. The complexity inherent in a learning coordinator can be managed by a modular architecture incorporating case based reasoning. In the interest of concreteness, the concepts are presented through a case study involving a knowledge based robotic system.

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A Study on the Future Storage System as brain coordinator

  • Yi, Cheon-Hee;Yi, Jae-Young
    • Journal of the Semiconductor & Display Technology
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    • v.8 no.1
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    • pp.39-42
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    • 2009
  • In this paper an attempt for realizing a storage system which works as a part of human brain has been discussed. The system is expected to be able to coordinate with human brain. And current storage may have inherent problem due to an intrinsic attribute of storage, exclusiveness. Directory structure in it must be a source of confusion, if it used out side of the range of limitation. Adapting multidimensional annotation of file name extension and directory-less file system, a new storage system able to associate and coordinate with human brain may be available near future. This paper showed that the limitation of current storage system clearly exists, because of human brain limitation to memorize directory name.

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A Study of improvement for Incident Command Systems in Korea (우리나라 재난현장지휘체계 개선방향)

  • We, Kum-Sook;Jeong, An-Young;Eum, Se-Joon
    • Journal of Korean Society of societal Security
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    • v.4 no.1
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    • pp.39-47
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    • 2011
  • According to the current basic law of disaster and safety management, Standard Incident Command System is limited to Emergency Rescue Function, and Incident Commanders are only Fire Fighting Agencies. The main purpose of this study is to provide some suggestions to improve general-purpose of Standard ICS for various incidents. Also, there are some suggestions for Emergency Operation Centers as a coordinator and supporter of mobilizing response resources in all large scale disaster.

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A Environment Data Monitoring System of Exhibition using Sensor Network and Nano-Q+ (센서네트워크와 Nano-Q+를 이용한 전시물 환경 정보 모니터링 시스템)

  • Kim, Gang-Seok;Huh, Jee-Wan;Song, Wang-Cheol
    • Proceedings of the Korea Information Processing Society Conference
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    • 2007.05a
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    • pp.867-869
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    • 2007
  • TinyOS기반 무선센서노드를 사용한 실시간 계측 데이터 측정 및 제어기술은 유비쿼터스 센서 네트워크 분야에 주로 사용되어 왔으나 다양한 응용이나 신뢰성 있는 무선 네트워크 연구 개발에 한계가 있는 것으로 알려져 있다. 본 논문에서는 ATMega128L을 장착한 최소 8대 이상의 nano-24 센서 노드모듈과 메모리 용량이 매우 제한적인 무선 센서 노드에 적합하다고 평가받고 있는 Nano-Q+를 사용하여 전시물 주변의 환경 정보를 실시간 측정하는 시스템을 구현하였다. 전시물 주변의 센서들은 하나의 PAN Coordinator를 중심으로 Start-Mesh 네트워크를 구성하여 환경 정보를 측정한다. 환경 정보를 전송 하기 위해 측정된 계측 데이터를 센서 네트워크의 PAN Coordinator 노드로부터 환경 모니터링 서버로 효율적으로 전송하기 위한 TCP기반 전송 프로그램을 구현하였다. 실험 결과 센서 노드 수와 관련된 PAN의 크기 및 샘플링 주기에 상관없이 안정적으로 계측 데이터 수신이 이루어짐을 확인 하였다.

국민학생을 위한 과학자료의 선택 및 평가

  • Kathryn S. Howie;Choi, Jeong-Ae
    • KLA journal
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    • v.16 no.8
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    • pp.20-23
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    • 1975
  • 본 번역문은 Library Trends Vol. 22. No. 4(1974.4)에 실린 논문을 번역한 것이다. 저자 Kathryn S. Howie는 Greenville에 있는 Alex I. Dupont School District의 District Coordinator of Library Services이다.

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A Study on the Improvement of Search and Rescue Coordination for Effective Response to Marine Casualties (해양사고의 효율적 대응을 위한 수색구조조정 개선방안 연구)

  • Yun, Jong-Hwui;Ha, Min-Jae;Smith, Matthew V.
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.21 no.1
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    • pp.34-39
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    • 2015
  • KCG, responsible Agency of maritime SAR operation has been known to address the marine casualties well, however, it was criticized because KCG failed to take prompt and effective response to the recent Ferry disaster at the very early stage. In this regards, the authors analyze the characteristics of marine incident with historical data, and also review and examine the national SAR system focusing on SAR coordination and human resources to make recommendation and suggestion in order to minimize the loss of lives to future marine incidents. As a result, KCG shall augment its capabilities, inter alia, fast libeboats and rescue helicopters for prompt response to marine incidents at the coastal waters, and KCG shall re-adjust the establishment of Rescue Coordination Center to improve operational problems of current system in accordance with IMO guidance, KCG is required to introduce mandatory training, qualification and certificate system to enhance the professionalism of SAR personnel.

Representation of Interactions in Data Model for Hybrid Structural Experiments (하이브리드 구조실험을 위한 데이터 모델에서의 상호작용의 표현)

  • Lee, Chang-Ho
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.23 no.2
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    • pp.123-137
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    • 2010
  • The hybrid structural experiment decomposes a structure into independent substructures that can be tested or simulated. The substructures being tested or simulated may be distributed at different facilities of different locations, and are managed by the simulation coordinator. There exist interactions among the simulation coordinator and the substructures since they give and receive the commands and feedbacks during the experimental process. These interactions are described in this paper for an example hybrid structural experiment using the classes and objects in the Lehigh Model which is one of the data models for structural experiments. The simulation coordinator and the substructures have the objects for the interaction data files, and are linked together through the same types of the interface links. The objects for the interactions presented in this paper can be implemented in a consistent way, and be used for developing the computer system for the hybrid structural experiments.

An Energy-Efficient In-Network Join Query Processing using Synopsis and Encoding in Sensor Network (센서 네트워크에서 시놉시스와 인코딩을 이용한 에너지 효율적인 인-네트워크 조인 질의 처리)

  • Yeo, Myung-Ho;Jang, Yong-Jin;Kim, Hyun-Ju;Yoo, Jae-Soo
    • The Journal of the Korea Contents Association
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    • v.11 no.2
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    • pp.126-134
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    • 2011
  • Recently, many researchers are interested in using join queries to correlate sensor readings stored in different regions. In the conventional algorithm, the preliminary join coordinator collects the synopsis from sensor nodes and determines a set of sensor readings that are required for processing the join query. Then, the base station collects only a part of sensor readings instead of whole readings and performs the final join process. However, it has a problem that incurs communication overhead for processing the preliminary join. In this paper, we propose a novel energy-efficient in-network join scheme that solves such a problem. The proposed scheme determines a preliminary join coordinator located to minimize the communication cost for the preliminary join. The coordinator prunes data that do not contribute to the join result and performs the compression of sensor readings in the early stage of the join processing. Therefore, the base station just collects a part of compressed sensor readings with the decompression table and determines the join result from them. In the result, the proposed scheme reduces communication costs for the preliminary join processing and prolongs the network lifetime.