• 제어로봇시스템학회:학술대회논문집
• /
• 1991.10a
• /
• pp.488-492
• /
• 1991

This paper deals with modeling and scheduling for flexible manufacturing systems(FMS). In modeling extended Petri nets are used to describe various and complex properties. To resolve multiple conflict without predefined properties, such as part selection, machine selection, rule-based scheduling method is introduced. This structure have a capability of on-line scheduling with systematic modeling description.

• Proceedings of the Korean Information Science Society Conference
• /
• 2012.06a
• /
• pp.262-264
• /
• 2012

유비쿼터스 지능형 공간에서 사용자의 개입 없이도 자율 실행하는 서비스 플러그 앤 플레이 시스템(Service Plug and Play System)은 기능적인 모델로서 총체적인 시스템의 협력 프로토콜 부재로 그 동시성 및 병렬성을 반영한 실행관리를 하기 어렵다. 이는 시스템을 구성하는 모듈로, 컨텍스트 수집기, 서비스 실행기, 공간관리기, 모바일 제어기 등이 UML의 시퀀스 다이어그램으로 모델링하여 각 기기의 기능과 실행흐름을 독립적으로 표현할 뿐, 기기간의 상호작용, 특히 병렬 및 동시 실행 알고리즘을 설계하고 검증하는 절차의 부재 때문이다. 본 논문에서, 각 기기의 실행 흐름 및 상호작용을 Petri Net을 이용하여 모델링함으로써, 시스템을 구성하는 각 디바이스의 상호작용 및 실행 흐름을 정의 하고 검증한다.

• Proceedings of the IEEK Conference
• /
• 2002.07a
• /
• pp.321-324
• /
• 2002

For a rule-based conversion of Hangout into the Roman alphabet rather than a word-for-word conversion, one must come up with a faultless model for the Korean standard pronunciation rules, which are the basis of the Romanization. It is on this foundation that the Korean-Roman alphabet conversion table can be created. For linguistic modeling using PetriNet, modeling boundary and notation of modeling can be defined. In order to describe PetriNet, which is a dynamic modeling tool, as a static one, one can model the standard Korean pronunciation rules and the Hangout-Roman alphabet notation by conversion into incident matrix Thus, this research attempts to develop a mathematical modeling tool for a natural language using PetriNet, and create a Korean-Roman alphabet conversion table.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.06a
• /
• pp.203-206
• /
• 2005

This paper presents a design experience of supervisory control system for agile and intelligent manufacturing(AIM). For effectively program job instructions, a Petri net-type graphical language is proposed and it can be applied to a various task such as concurrency and synchronization. PGL is consisted of PGL editor, PGL analyzer and PGL translator; PGL editor generates a job instruction program using graphic symbol. PGL analyzer prevents a deadlock or resource allocation of unit cell. PGL translator transfers to adequate sequential job commands of each unit cell.

• Journal of Ocean Engineering and Technology
• /
• v.15 no.4
• /
• pp.101-107
• /
• 2001

This paper describes a fault diagnosis method by a T-invariance of Petri Net (PN). First, a complicated fault system with some failure is modeled into a PN graphic expressions. Next, the PN model is analyzed by using the backward chaining of T-invariance to find out causes of the faults. In this step, an inter-node search technique which is suggested in this paper is applied for reducing searching area in the fault system. Also, a novel idea to compose incidence matrices which have different dimension each other in PN model is proposed. As the new knowledges which is discovered newly about faults can be added easily to conventional systems, the diagnosis system will be very flexible. Finally, the proposed method is applied to the automobile fault diagnosis system to confirm the validity of the method.

• Journal of the Korean Society for Precision Engineering
• /
• v.16 no.7
• /
• pp.132-143
• /
• 1999

In this study, an intermediate model is presented as a new method for development of a parametric simulation program. This model enables us to analyze effectively the static and dynamic structure of a real production system. The static structure of the real system can be modelled in an entity-relationship diagram and the dynamic structure of the real system in a Petri net. The intermediate model consists of an entity-relationship diagram and a Petri net. Using this intermediate model man can not only reduce the time and cost for simulation program development, but also increase the modelling reliability of the developed simulation program. To show the usefulness of this intermediate model. the intermediate models for two production subsystems, manufacturing sub-system and transport subsystem, are set up.

• Management Science and Financial Engineering
• /
• v.3 no.1
• /
• pp.15-38
• /
• 1997

In a flexible manufacturing system, a cell controller is able to identify and evaluate a number of alternative decisions to meet the objectives set by the factory level controller. In this paper, a Petri net-based cell controller is presented to accomplish this task. A static model is developed by using the Integrated Computer Aided Definition(IDEF0) method to represent clear functional relationships among the objects of the system. Based on the static model, two Petri net models are developed for the physical part flow and for the information flow. Multiple decision alternatives are generated from the physical part flow model and are synchronized with the information flow model for execution of the selected alternative.

• Management Science and Financial Engineering
• /
• v.3 no.2
• /
• pp.71-92
• /
• 1997

Developing FMS controllers has been a difficult problem largely because of the variety of the system configuration. The purpose of this paper is to develop a method of building an FMS controller. The controller consists of control module and execution module. A hierarchically layered structure of these modules is proposed. The control module generates abstract-level execution requested by identifying a set of activities that can be executed without creating any irregular state. The execution module transmits the requests to physical device controllers and reports back the completion of the requests to the control module. Both of these two modules use Petri Net-based models. In this paper, a controllable Petri Net model is automatically synthesized from declarative specifications provided by a user. An execution Petri Net model for the execution module is designed to ensure the consistency between the control module and the real target system. The controller operates in MMS on TCP/IP and UNIX environment.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.19 no.2
• /
• pp.322-330
• /
• 1994

SIBs(Service Independent Building block) are defined in CCITT advanced intelligent network concept model for supporting various services in the future. This paper describes the protocol modeling and verification for basic call process SIB. For modeling, we use Petri Net and verify this modeling by analyzing reachability tree of Petri Net. Results of this paper should be used for design and implementation of basic call process SIB.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2003.11a
• /
• pp.385-388
• /
• 2003

인터넷 인구의 폭주로 트래픽을 줄이려는 노력이 일고 있는 가운데, 우리는 기존에 웹 서버의 성능를 리눅스 커널 단에서 향상시키는 방법을 제안하였다. 사용자 영역의 스레드를 사용하지 않고 커널 영역의 스레드를 사용하고 CPU 개수와 동일한 스레드만 사용함으로서 스레드간의 컨텍스트 스위칭과 시스템 콜 사용의 오버헤드를 줄일수 있었다. 이번에는 이 구조를 CPN(Coloured Petri-Net)을 사용하여 논리적으로 분해하고 그 동작특성을 이해하여 모델링과 실제 데이터를 비교함으로서 프로그램 동작에 관한 논리적 문제점을 발견할 수 있고, 동작특성의 시간특성을 알 수 있다.