• 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.

• Korean Journal of Computational Design and Engineering
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• v.13 no.6
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• pp.412-420
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• 2008

In order to design the large complex structures like VLFS (Very Large Floating Structures), it is essential the cooperation between the experts in various fields; structural engineering expert, fluid mechanics expert, mooring system engineer, and so on. This paper describes the development of an integrated system to support the cooperative design between various experts and project manager. This integrated system is designed to be operated in Web environment and it contains the support of design DB and 3D graphical tool, negotiation tool for task allocation, and various engineering supporting tools for each design step. The user group of this system can be classified as Project Manager, Engineering Expert, DB Builder, and System Administrator. All of the engineering data is saved after and during the process of the design projects and all participants can be connected by Internet without the limit of time or space constraints.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1590-1595
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• 2003

Direct drive servovalve(DDV) is a kind of one-stage valve since the rotary motion of DC motor is directly transferred to the linear motion of valve spool through the link. Since the structure of DDV is simple, it is less expensive, more reliable and offers reduced internal leakage and reduced sensitivity to fluid contamination. However, the flow force effect on the spool motion is significant such that it induces large steady-state error in a step response. If the proportional control gain is increased to reduce the steady-state error, the system becomes unstable. In order to satisfy the system design requirements, the lead-lag controller is designed using the complex method that is one kind of constrained direct search method.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.11
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• pp.1719-1726
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• 2004

Direct drive servovalve(DDV) is a kind of one-stage valve because the main spool valve is directly driven by the DC motor. Since the structure of DDV is simple, it is less expensive, more reliable and offers reduced internal leakage and reduced sensitivity to fluid contamination. However, the flow force effect on the spool motion is significant such that it induces large steady-state error in a step response. If the proportional control gain is increased to reduce the steady-state error, the system becomes unstable. In order to satisfy the system design requirements, the lead-lag controller is designed using the complex method that is one kind of constrained direct search method.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.1205-1211
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• 2017

The Propulsion System Test Complex(PSTC) was constructed for the verification test of each stage's propulsion system of KSLV-II. Main Control System(MCS) is the system to operate the onboard equipment and the ground equipment of the PSTC simultaneously. This paper describes the critical design, the development status, and test results of Main Control System. The MCS will be used for the interface connection between ground control systems and onboard equipment. Test sequence and operation process of the Work Manager will be conducted by MCS.

• Fire Science and Engineering
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• v.30 no.4
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• pp.6-13
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• 2016

With regard to smoke control system, the design guidelines of smoke exhaust for accommodation and smoke control for evacuation stairs and vestibule has been proposed domestically, but after reviewing the applicability to modern buildings that tend to be larger, higher and complex, a smoke control system according to domestic design guidelines might have difficulty in securing the safety from smoke in a fire. Therefore, it is necessary to adopt the performance-based design of a smoke control system that can enhance the safety and integrate the smoke control functions and design depending on the characteristics of fire and building structure in the case of fire in a large, high-rise, and complex building. This study analyzed the domestic design guidelines of a smoke control system and this paper proposes the part requiring improvement, and examines the legal system and guidelines on performance-based design of smoke control system in foreign countries.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.157-161
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• 2004

Urban transit is system that offer target Performance and function because various lower part system such as vehicles, signaling, power supply, rail track is consisted as complex. It is important first of all that describe correctly system requirement until configuration of system, design, manufacture, installation and test verification so that the complicated urban transit system is to act safety and reliable and to display target Performance and function properly. The system requirement assist the system developer to comprehensive the performance and function of system in basic design. Therefore, In this paper wishes to study way to analyze system of system requirement and apply to Urban transit.

• Journal of Information Technology Services
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• v.13 no.2
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• pp.151-161
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• 2014

KOSPI 200 index options market has the highest trading volume in the global options markets. The risk and return structure of options contracts are very complex. Volatility complicates options trading because volatility plays a central role in options pricing process. This study develops a trading system for KOSPI 200 index options trading using KOSPI 200 volatility index. We design a database system to handle the complex options information such as price, volume, maturity, strike price, and volatility using Oracle DBMS. We then develop options trading strategies to test how the volatility index is related to the prices of complicated options trading strategies. Back test procedure is presented with PL/SQL of Oracle DBMS. We simulate the suggested trading system using historical data set of KOSPI 200 index options from December 2008 to April 2012.

• Proceedings of the KIEE Conference
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• 1993.11a
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• pp.326-328
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• 1993

Modelling theory, based on differential equations, is not an adequate tool for solving the problems of complex system. Identification of complex system using GMDH(group method of data handling) is more appropriate for this problems. In this paper, GMDH algorithm is used to identify the nonlinear plant and to design model following nonlinear control system. Simulation for the DC motor show the good performance of model following nonlinear control system.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2008.05a
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• pp.274-279
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• 2008

The significance of complexation facilities in Japan is to recognize the problems resulting from social/economic changes such as rapid informatization, globalization, low rates of birth, and aging population, and to strengthen the national competitiveness and urban advantages. Likewise, there have been increasing demands for community facilities that can meet the new requirements in terms of efficient administration and resident-centered administrative service system in line with changes in the society and administrative conditions. Thus, analyzed are cases concerning complex community facilities in Japan that have coped with changes in consciousness in the community earlier than in Korea. Specifically, the concept of modernday complex community facility is investigated, and the complexation of Korea Japan complex community facilities is divided to physical complexation and functional complexation to grasp the types. The complex community facilities are compared, and the characteristics in terms of spatial composition are also examined. The result of analyzing complex community facility cases is comprehensively analyzed to find out new possibilities in this regard.