• International Journal of Aeronautical and Space Sciences
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• v.11 no.2
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• pp.126-130
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• 2010

This paper presents the conceptual design of a multi-rotor unmanned aerial vehicle (UAV) based on an axiomatic design. In most aerial vehicle design approaches, design configurations are affected by past and current design tendencies as well as an engineer's preferences. In order to design a systematic design framework and provide fruitful design configurations for a new type of rotorcraft, the axiomatic design theory is applied to the conceptual design process. Axiomatic design is a design methodology of a system that uses two design axioms by applying matrix methods to systematically analyze the transformation of customer needs into functional requirements (FRs), design parameters (DPs), and process variables. This paper deals with two conceptual rotary wing UAV designs, and the evaluations of tri-rotor and quad-rotor UAVs with proposed axiomatic approach. In this design methodology, design configurations are mainly affected by the selection of FRs, constraints, and DPs.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.05a
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• pp.352-355
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• 2004

The objective of this work is to develop a new design method to find optimal coils, especially the optimal coil configuration of an optical pickup actuator. In designing actuator coils, the developed Lorenz force in the coils along the desired direction should be made as large as possible while forces and torques in other directions should be made as small as possible. The design methodology we are developing is a systematic approach that can generate optimal coil configurations for given permanent magnet configurations. To consider the best coil configuration among all feasible coil configurations, we formulate the design problem as a topology optimization of a coil. The present formulation for coil design is noble in the sense that the existing topology optimization is mainly concerned with the design of yokes and permanent magnets and that the optimization of actuator coils is so far limited within shape or size optimization. Though the present design methodology applies to any problem, the specific design example considered is the design of fine-pattern tracking and focusing coils.

• Transactions on Control, Automation and Systems Engineering
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• v.1 no.2
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• pp.87-93
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• 1999

This paper proposes a systematic designs methodology for the Takagi-Sugeno (TS) model based fuzzy control systems with guaranteed stability and pre-specified transient performance for the application to a nonlinear magnetic bearing system. More significantly, in the proposed methodology , the control design problems which considers both stability and desired transient performance are reduced to the standard LMI problems . Therefore, solving these LMI constraints directly (not trial and error) leads to a fuzzy state-feedback controller such that the resulting fuzzy control system meets above two objectives. Simulation and experimentation results show that the proposed LMI-based design methodology yields only the maximized stability boundary but also the desired transient responses.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.81-84
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• 2002

With the increasing market dynamics, the concept of agile manufacturing system gets more and more attention. For a manufacturing system to be agile, the supply chain should also have sufficient agility. However, most of the supply chain design methods are based on the human experience or trial-and-errors. In this paper, a systematic methodology is proposed. It takes into account the agility of supply chain, the behavior of which is represented as a beam model in mechanics, composed of supplier, transporter, manufacturer, distributor, and customer.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.1165-1170
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• 2005

This paper describes an information model, devised to manage roadway design information and to improve the collaboration among the multidisciplinary design teams. An analysis concerning the workflow, the rules and the functions of current roadway design was conducted. A process model based on the result of the analysis was developed by utilizing IDEF0 methodology. The process model reflects the interdependencies among multidisciplinary design disciplines and is capable of managing communication processes. This paper also discusses the design information hierarchy and the component representation schemes for systematic design information management. It is anticipated that the proposed information model would be able to improve the overall process of design of roadway construction projects by managing design information and helping the participants communicate and share information of the project effectively.

• Journal of Korean Society for Quality Management
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• v.30 no.4
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• pp.137-153
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• 2002

Viewed as a more systematic approach of creating high quality products and bringing them into market at a lower cost and in significantly less time, it attracts the attention of quality designers to quality function deployment (QFD) approach. In attempt to reduce the design cycle, the industry has responded with concurrent design effort. In a sense, concurrent engineering refers to the integration of various activities within the broad scope of the product life cycle ［17］. Over the last ten years, much has been written about QFD but little has been available in terms of the underlying guide methodology. The methodology of QFD is quite simple and many will say that they have done it in the past but just have not formalized it into the form that this discipline requires. QFD ties the product, user, value, and manufacturing viewpoints together in a continuous process of defining the product design and manufacturing requirements. The value viewpoint recognizes the cost to obtain certain functionality, and the manufacturing viewpoint addresses conformance to requirements, but in a broader sense, the variability in production. In this paper, the QFD system acquisitions are described, and two heuristic approaches solving for the complex design process, especially the size reduction of design process and precedence-constrained relationship in QFD are proposed, and the empirical example is illustrated.

• Journal of Korean Society for Quality Management
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• v.33 no.2
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• pp.74-86
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• 2005

The project objectives, called critical-to-quality (CTQs) in six sigma, should be defined to faithfully reflect the customer requirements. The identification of such a set of CTQs, which is currently done using brainstorming in practice, is a challenging task. Notwithstanding the rapid growth of the six sigma literature, development of a systematic procedure for identifying CTQs has scarcely been addressed. This paper proposes a systematic method for generating CTQ candidates based on the given voice of the customer in the DFSS/C (Design for Six Sigma / Commercial) context. By providing a step-by-step procedure, the proposed method ensures that all the important CTQ candidates are identified and subjective judgments are minimally required. Hence, the shortcomings associated with the existing practice based on brainstorming can be effectively overcome. The unique characteristics of the proposed method are also demonstrated via a case study.

• Korean Journal of Computational Design and Engineering
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• v.22 no.2
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• pp.129-140
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• 2017

This paper presents a systematic approach for design of timely and proper layouts of a manufacturing system facilitating reconfigurability, referred to as a reconfigurable manufacturing system. A proper methodology for design of a system layout is required for reconfiguration planning - adding or removing machines for supplying the exact capacity needed to fulfill market demands, as well as minimizing the cost of adding new machines. In this paper, theory of constraints is used to make reconfiguration manufacturing systems more cost-effective and efficiency. The proposed approach is validated by using a real industrial case. This paper suggests that the proposed study should be performed concurrently with the design of a new manufacturing system.

• Korean Journal of Computational Design and Engineering
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• v.15 no.2
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• pp.94-105
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• 2010

Todays, there is fast transition about the new manufacturing IT methodologies from the conceptual phase into the practical application phase for the strengthening of enterprise competitiveness in manufacturing industry. One of those new methodologies is PLM (Product Life-cycle Management). PLM methodology consists of 3D CAD for the product design, PDM (Product Data Management) for the data management based on the collaboration platform and lastly DM (Digital Manufacturing). DM has evoluted from the stand-alone computer simulation of early 1980s, and now it covers the overall production development and production. Unfortunately, there exist serious critical problems about the actual application of DM for the real work. This is owing to the transition of the point of view from stand-alone type application (such as flow simulation or robot simulation) to that of business process about product development and production management. In this paper, we propose an application framework for the successful project with the digital manufacturing methodology with the concept of Information Strategy Planning, which enables the systematic diagnosis and the quantitative evaluation. Also, we introduce the actual practice of the proposing framework with the ISP project for 'Analysis & Simulation Technique of manufacturing process project' that is being conducted by Chungnam Techno Park.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.225-228
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• 2002

When the fuzzy logic controller (FLC), which is designed based on the plant model, is applied to the real control system, satisfactory control performance may not be attained due to modeling errors from the plant model. In such cases, the control parameters of the controller must be adjusted to enhance control performance. Until now, the trial and error method has been used, consuming much time and effort. To resolve such problem, response surface methodology (RSM), a new method of adjusting the control parameters of the controller, is suggested. This method is more systematic than the previous trial and error method, and thus optimal solutions can be provided with less tuning. First, the initial values of the control parameters were determined through the plant model and the optimization algorithm. Then, designed experiments were performed in the region around the initial values, determining the optimal values of the control parameters which satisfy both the rise time and overshoot simultaneously.