• Journal of Institute of Control, Robotics and Systems
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• v.8 no.8
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• pp.706-712
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• 2002

In general, a deadlock in flexible manufacturing systems (FMSs) is caused by a resource limitation and the diversity of routings. However, the deadlock of industrial controllers such as programmable logic controllers (PLCs) can occur from different causes compared with those in general FMSs. The deadlock of PLCs is usually caused by an error signal between PLCs and manufacturing systems. In this paper, we propose a deadlock detection and recovery (DDR) algorithm to resolve the deadlock problem of PLCs at design stage. This paper employs the MAPN (modified automation Petri net), MTPL (modified token passing logic), and ECC (efficient code conversion) algorithm to model manufacturing systems and to convert a Petri net model into a desired LD (ladder diagram). Finally, an example of manufacturing systems is provided to illustrate the proposed DDR algorithm.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.745-746
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• 2016

The compensation effects of the control positions for net residual dispersion (NRD) on the distorted WDM cjannels in dispersion-managed optical links with artificially distributed single mode fiber (SMF) lengths and residual dispersion per span (RDPS) are evaluated.

• Journal of Digital Convergence
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• v.10 no.6
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• pp.189-196
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• 2012

In this paper, we propose a Scorm-based Sequencing & Navigation Model for Collaborative Learning. It is an e-Learning process control model that is used to efficiently and graphically defining Scorm's content aggregation model and its sequencing prerequistites through a formal approach. To define a process based model uses the expanded ICN(Information Control Net) model. which is called SCOSNCN(SCO Sequencing & Navigation Control Net). We strongly believe that the process-driven model delivers a way of much more convenient content aggregating work and system, in terms of not only defining the intended sequence and ordering of learning activities, but also building the runtime environment for sequencing and navigation of learning activities and experiences.

• Proceedings of the Korea Information Processing Society Conference
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• 2000.10a
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• pp.39-42
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• 2000

본 논문은 워크플로우 모델링 도구인 ICN(Information Control Net)을 기반으로 하는 워크플로우 제어 의존성 분석을 위한 도구를 구현하였다. 즉, ICN 모델로 정의된 워크플로우의 각 단위업무(Activity)들 간에 존재하는 제어 의존 관계를 표현하기 위한 제어 의존 넷(Control Dependency Net)을 정형적인 방법으로 정의, 표현하였다. 본 논문에서 정의된 제어 의존 넷은 워크플로우 빌드타임(Build-time) 측면과 런타임(Run-time)측면에서 여러 가지 기능을 제공한다. 전자의 측면에서는 워크플로우 모델링시 시멘틱 에러 테스팅 기능을 효과적으로 적용될 수 있으며 후자의 측면에서는 제어 흐름의 동적 변경(dynamic Change)기능의 완결성 및 프로세스 안의 단위업무(Activity) 간의 경로 및 경로 대한 정보를 제공한다.

• Proceedings of the Korean Information Science Society Conference
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• 2000.04b
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• pp.33-35
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• 2000

본 논문에서는 워크플로우 모델링 도구인 ICN(Information Control Net)모델을 기반으로 하는 워크플로우 제어 의존성 분석 메커니즘을 제안하였다. 즉, ICN 모델로 정의된 워크플로우의 각 액티버티들 간에 존재하는 제어 의존 관계를 표현하기 위한 제어 의존 넷(Control Dependency Net)을 정형적인 방법으로 정의하였고, ICN 모델로부터 제어 의존 넷을 생성하는 알고리즘을 정의하였다. 본 논문에서 제안한 워크플로우 제어 의존성 분석 메커니즘은 워크플로우 빌드타임(Build-time)측면과 워크플로우 런타임(Run-time)측면에서 중요한 의미를 갖는다. 전자의 측면에서는 워크플로우의 복잡성이 증가함에 따라 더욱 요구되고 있는 워크플로우의 시멘틱 에러 테스팅 기능에 효과적으로 적용될 수 있으며, 후자의 측면에서는 워크플로우의 성공적인 적용을 위해 필수적으로 요구되는 제어 흐름의 동적 변경(Dynamic Change)지원 기능의 완결성을 향상시키는데 효과적으로 활용될 수 있다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.11
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• pp.2205-2217
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• 2015

Bio-inspired routing protocol uses a principle of swarm intelligence, which finds the optimal path to the destination in a distributed and autonomous way in dynamic environments, so that it can maximize routing performances, reduce control overhead, and recover a path failure quickly according to the change of network topology. In this paper, we propose a bio-inspired routing protocol for mobile ad hoc networks. The proposed scheme uses a function of overhearing via wireless media in order to obtain the routing information without additional overhead. Through overhearing, the pheromone is diffused around the shortest path between the source and destination. Based on this diffused pheromone, a probabilistic path exploration is executed and the useful alternative routes between the source and destination are collected. Therefore, the proposed routing protocol can ensure the up-to-date routing information while reducing the control overhead. The simulation results show that the proposed scheme outperforms the typical AODV and AntHocNet protocols in terms of routing performances and significantly decreases the routing overhead against the AntHocNet.

• Journal of the Korean Society for Library and Information Science
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• v.40 no.2
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• pp.195-216
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• 2006

This study intends to analyze the meanings and values of shared cataloging in public libraries. Emphasis was on verifying how useful KOLIS-NET is as a tool in order to share bibliographic data and library resources. To the end. this study investigates the recognition and participation of KOLIS-NET in public libraries. Finally suggested is strategies to improve both the poor quality and the poor services. The data needed for discussion were collected by an in-depth interviews with catalogers and a survey with 216 public libraries.

• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.1254-1256
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• 1996

Design methods for sequence flow controllers play an important role in industrial automation. To design a flexible, reusable, and maintainable control software has become a key issue nowadays. Petri net has been emerging as an important tool to provide an integrated solution for modeling, analysis, simulation, and control of industrial automated systems recently. This paper describes an international standard of programming languages for programmable logic controllers, IEC 1131-3 SFC( Sequential Function Chart), and the sequence flow control method for an SFC using a Petri net-like model.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.05a
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• pp.566-569
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• 2011

동기 및 비동기 데이터를 동시에 전송할 수 있는 MOST(Media Oriented Systems Transport) 네트워크는 최근 자동차 멀티미디어 시스템에 가장 광범위하게 사용되고 있는 통신 시스템이다. MOST는 주로 링 형태로 연결되어지며 마스터 역할을 하는 장치가 반드시 하나 존재하고 여러 개의 슬레이브 장치들이 존재한다. 또한 MOST 네트워크에 연결된 여러 장치를 제어할 수 있는 HMI가 필요하다. HMI는 독립적인 장치로 만들 수도 있지만 일반적으로 Master 기능을 통합하여 구현한다. 본 논문에서는 MOST 네트워크에서 동영상 재생 플레이어인 DVD를 제어하기 위해서 HMI 역할을 하는 응용프로그램을 설계 및 구현하였다. DVD 제어를 위한 HMI 프로그램은 MOST NetServices API를 이용하여서 컨트롤 메시지를 전송해서 DVD 장치를 제어하며, 사용자가 쉽게 사용할 수 있는 GUI 형태로 구현하였다. MOST25 PCI 카드와 MOST DVD 플레이어 장치를 네트워크로 연결하고, PC에 DVD 장치 제어 HMI를 구현한 후 테스트하여 정상적으로 동작함을 확인하였다.

• Journal of Internet Computing and Services
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• v.19 no.3
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• pp.25-33
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• 2018

This paper proposes a cloud workflow model theoretically supported by the information control net modeling methodology as a cloud workflow modeling methodology that is mandatory in implementing realtime enterprise workflow management systems running with cloud computing environments. The eventual goal of the cloud workflow model proposed in this paper is to support those cloud workflow architectures reflecting the types of cloud deployment models such as private, community, public, and hybrid cloud deployment models. Moreover, the proposed model is a mathematical graph model that is extended from the information control net modeling methodology used in conventional enterprise workflow modeling, and it aims to theoretically couple this methodology with the cloud deployment models. Finally, this paper tries to verify the feasibility of the proposed model by building a possible cloud workflow architecture and its cloud workflow services on a realtime enterpeise cloud workflow management system.