• Journal of Advanced Marine Engineering and Technology
• /
• v.22 no.6
• /
• pp.928-934
• /
• 1998

This paper describes a fully digitalized driver for BLDC motors which is realized by a single chip microprocessor. The speed change can be done by using the signal obtained from the position detecting sensor and adjusting the pulse width at the input channel of power module. In order to establish a speed control system a repetitive control method is adopted to track a periodic refer-ence change in the BLDC motor system. The experimental results show accurate reference track-ing performance under the given periodic reference in the repetitive controller design.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2007.06a
• /
• pp.387-388
• /
• 2007

• Proceedings of the KSR Conference
• /
• 2006.11b
• /
• pp.170-173
• /
• 2006

Requirement management is an essential process that has a significant influence on the project success. Due to the evolutionary development nature of requirement, the effective management for requirement must include change process and configuration control. This paper describes how to implement effective requirement management process to the Korea Tilting Train eXpress development with the application of a model based systems engineering tool.

• IE interfaces
• /
• v.7 no.3
• /
• pp.31-37
• /
• 1994

제조업의 경영환경을 중심으로 CIM의 개념을 정의하고 개발, 생산, 및 영업 측면에서 구체화 하였다. CIM의 요소를 영업정보, 기술정보 및 생산정보로 구분하여 각각에 대한 실현방안을 개괄적으로 단순화 하였다. 영업정보는 궁극적으로 정확한 수요예측을 위한 것이며 기술정보는 엔지니어링 데이터베이스로 체계화되면 생산정보는 양질의 구매와 원활한 생산 활 동을 위한 시스템의 구성을 목표로 한다. 기업 활동을 시스템 모델화하여 고찰하면 자본에 대한 손익을 자율적으로 규제하고 조정하는 역할로 규정한다. 여기서 투자자는 투자액에 대한 이익배당을 얻거나 손실을 보게 도며 기업 활동은 확장 혹은 축소된다. CIM은 궁극적으로 기업 활동의 순환주기를 단축시키고 기업 활동의 결과예측의 정확도를 높이는 컴퓨터를 이용한 수단이라고 볼 수 있다.

• Journal of Advanced Marine Engineering and Technology
• /
• v.35 no.1
• /
• pp.82-88
• /
• 2011

The objective of this study is to investigate the validity of the dynamic sub-grid G-equation model to a complex turbulent premixed combustion such as bluff body stabilized turbulent premixed flames for the considering of the realistic engineering application. In this study, a new turbulent flame speed model, introduced by the sub-grid turbulent diffusivity and the flame thickness, is also proposed and is compared with an usual model using sub-grid turbulent intensity and with the experimental data. The calculated results can predict the velocity and temperature of the combustion flow in good agreement with the experiment data.

• Journal of Korea Multimedia Society
• /
• v.5 no.6
• /
• pp.730-744
• /
• 2002

A Web-Based Information System(WBIS), a typical structure of recently information systems, should be dynamically restructured in order to satisfy user's need and make a profit. Thus, we should analyze and modelize the navigational structure of WBIS and utilize it by modeling the navigational structure of behavior of user through log-file as system restructuring. In this paper, we propose the modeling method for navigational structure and user behavior to restructure WBIS including shopping mall. Also, we suggest the structural model, state transition model, Petri net model and analysis method and analyze and implement modeling algorithm for user behavior to analyze log-file of it. Then, we propose some restructuring heuristic and apply the methods to the example of WBIS.

• Journal of KIISE
• /
• v.44 no.12
• /
• pp.1307-1312
• /
• 2017

Due to their convergence with state-of-the-art ICT technologies, the complexity and reliability demands of industrial automation systems have been rapidly increasing. In recent years, to cope with these demands, several research works have been carried out to adopt formal methods to the application development cycle at the early design stage. In this paper, we propose an automated code generation framework for industrial automation applications, based on a timed automata model. As a case study, we developed a formal model for a traffic light control system and verified the timing properties described in the specification. We finally demonstrated that the operation of a test-bed based on the auto-generated native code was identical to that of the model specification.

• Journal of Advanced Marine Engineering and Technology
• /
• v.36 no.1
• /
• pp.126-132
• /
• 2012

This paper suggests a design method of the model-following H${\infty}$ control system having robust performance. This H${\infty}$ control system is designed by applying genetic algorithm(GA) with reference model to the optimal determination of weighting functions and design parameter ${\gamma}$ that are given by Glover-Doyle algorithm which can design H${\infty}$ controller in the state space. These weighting functions and design parameter ${\gamma}$ are optimized simultaneously in the search domain guaranteeing the robust performance of closed-loop system. The effectiveness of this H${\infty}$ control system is verified by applying to the boiler-turbine control system.

• Journal of the Society of Naval Architects of Korea
• /
• v.31 no.3
• /
• pp.19-30
• /
• 1994

The modeling of a product data is becomming more and more important in engineering environment, especially for the development of CAD/CAM system as a basis of computer integrated manufacturing system. Model is a formalized representation of the real world, and modeling is the task to identify, abstract, and formalize the product information into an unambiguous representation. In this study, the piping system, one of typical product of ship outfitting system, is modeled. The STEP idea is followed to provide a common mechanism to represent the product information throughout the life-cycle, and the object oriented paradigm is used in the analysis and design of the model. The definitions given within this model are independent of the specific application domain so that the same methodology can be used for other purpose.

• Journal of Advanced Marine Engineering and Technology
• /
• v.34 no.1
• /
• pp.102-108
• /
• 2010

The T-S fuzzy model of a ship is made from the nonlinear extension of Nomoto's 2nd-order model as the previous step before designing of the fuzzy type autopilot to consider the design specifications and the economic efficiency. The T-S fuzzy model is considered as a design variable of the heading angular velocity of ship. The linear models will be combined as "IF-THEN" fuzzy rules after get in this one area of the linear model(sub-system) by change of the heading angular velocity of a ship. The dynamic characteristic of a ship with the parameters of linear models and fuzzy membership functions are estimated to match by using the model adjustment technic with input/output data and a RCGA.