• Biotechnology and Bioprocess Engineering:BBE
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• v.3 no.2
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• pp.103-108
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• 1998

A hydrophobic substrate triolein was hydrolyzed by lipase in a mono-phase reaction system containing cyclodextrin(CD) as emulsifier. The triolein was transformation to an emulsion-like state in the CD containing reaction system in contrast to the oil-droplet like state without CD due to the formation of an inclusion complex between the lipids and CDs. The hydyrolysis reaction increased substantially in the CD containing reaction system, and the optimum reaction conditions including the amount of lipase, ${\beta}$-CD concentration, and mixing ratio of triolein and ${\beta}$-CD, were determined. The performance of the enzyme reaction in a mono-phase reaction system was compared with that of a two-phase reaction system which used water immiscible hexane as the organic solvent. The role of a CD in the mono-phase reaction system was elucidated by comparing the degree of the inclusion complex formation with triolein and oleic acid, Km and Vmax values, and product inhibition by oleic aicd in aqueous and CD containing reaction systems. The resulting enhanced reaction seems to be caused by two phenomena; the increased accessibility of lipase to triolein and reduced product inhibition by oleic acid through the formation of an inclusion complex.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.435-435
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• 2000

Light Rail Transit (LRT) system is a complex and large system in which there are many subsystems, interfaces, functions and demanding performance requirements. Because many contractors participate in the development, it is necessary to apply methods of sharing common objectives and communicating effectively among all of the stakeholders. This paper shows not only the methodology and the results of computer-aided systems engineering including requirement management, functional analysis and architecting LRT system, but also propose a tool to help manage a project by linking WBS (Work Breakdown Structure), work organization and PBS (Product Breakdown Structure). The application of computer-aided tool RDD-100 provides the capability to model product design knowledge and decisions about important issues such as architecting the top-level system. The product design knowledge will be essential in integrating the following life-cycle phase activities over the life of the LRT system. Additionally, when a new generation train system is required, the reuse of the database can increase the system design productivity and effectiveness significantly.

• Korean Journal of Computational Design and Engineering
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• v.13 no.2
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• pp.121-130
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• 2008

The concept of integrated product information has been universalized so that many manufacturing industries have applied the concept to their production system. The field of PDM (Product Data Management), which is one of the core components of the integrated product information, is not an exception. Therefore, various PLM (Product Lifecycle Management) software providers are in process of suggesting the PDM solutions. As the PDM solution is widely adopted in the manufacturing industries, the successful application of the solution has been gathering more strength in manipulation of the product information. However, the standardized implementation methodology is stuck in the basic level contrast with the enhanced PDM's functionality and capability. Present study refers to the application of UML (Unified Modeling Language), which is an object oriented modeling description, to PDM system development procedure. The advantage of UML is its efficiency and effectiveness in handling complex requirement often found in PDM implementation works. This paper shows the integration of PDM and UML proposes a philosophy for the support of requirement analysis throughout the full implementation of PDM system.

• 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.

• International Journal of Naval Architecture and Ocean Engineering
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• v.11 no.1
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• pp.11-21
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• 2019

In product design, the initial design stage is being increasingly emphasized because it significantly influences the successive product development and production stages. However, for larger and more complex products, it is very difficult to accurately predict product reliability in the initial design stage. Various design methodologies have been proposed to resolve this issue, but maintaining reliability while exploring design alternatives is yet to be achieved. Therefore, this paper proposes a methodology for conceptual design considering reliability issues that may arise in the successive detailed design stages. The methodology integrates the independency of axiomatic design and the hierarchical structure of failure mode, effects, and criticality analysis (FMECA), which is a technique widely used to analyze product reliability. We applied the proposed methodology to a liquefied natural gas fuel gas supply system to verify its effectiveness in the reliability improvement of the design process.

• Archives of design research
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• v.13
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• pp.212-221
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• 1996

The necessity of imformation on product design process is increased in recently years, because a product can be called a mass of information and becomes more complex as long as technology is developed. But the present product development method is like a relay race. In this sequential process, information is transferred from one department to other departments like \"over the wall\". And communication gaps among departments are generated, so imformation cannot be controlled very well. Therefore it is needed to innovate the design process. The information system proposedin this study is an application software which can be useful for integrated product design process. It has been developed primarily for use in IBN PC and windows environment. It comprises four functional modules; functions of handing the overall project information (document, ideaskech, rendering, drawing); functions of decision making production problems in design project process; functions of groupware which can link with other departments; functions of comprehensive database with production.roduction.

• Honam Mathematical Journal
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• v.35 no.4
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• pp.809-817
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• 2013

We research properties of a corresponding Cauchy theorem of hyperholomorphic functions in an open set of product complex spaces, in the sense of complex Clifford analysis.

• Korean Journal of Computational Design and Engineering
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• v.13 no.5
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• pp.334-341
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• 2008

Computer-aided engineering (CAE) analysis is considered essential for product development because it decreases the simulation time, reduces the prototyping costs, and enhances the reusability of product parts. The reuse of quality-assured CAE data has been continually increasing due to the extension of product lifecycle management; PLM, which is widely used, shortens the product development cycle and improves the product quality. However, less attention has been paid to systematic research on the interoperability of CAE data because of the diversity of CAE data and because the structure of CAE data is more complex than that of CAD data. In this paper, we suggest a CAE data exchange method for the effective sharing of geometric and analysis data. The method relies on heterogeneous CAE systems, a virtual reality system, and our developed CAE middleware for CAE data exchange. We also designed a generic CAE kernel, which is a critical part of the CAE middleware. The kernel offers a way of storing analysis data from various CAE systems, and, with the aid of a script command, enabling the data to be translated for a different system. The reuse of CAE data is enhanced by the fact that the CAE middle-ware can be linked with a virtual reality system or a product data management system.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.10 no.1
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• pp.96-99
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• 2014

The aim of the study was to evaluate the water treatment of pressurized water reactor secondary side by the mixed amine of ammonia and ethanolamine, from the standpoint of corrosion control, as compared with all volatile treatment of ammonia. The pressurized water reactor systems have switched a secondary side pH control agent to minimize the corrosion in the moisture separator/reheater and feedwater heater systems and the transport of corrosion products into steam generator. As results of field test, pH was increased in the steam generator and the wet steam area of moisture separator/reheater and the concentration of Fe were decreased by more than 50% as compared with water treatment of ammonia.

• Korean Journal of Computational Design and Engineering
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• v.12 no.3
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• pp.209-219
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• 2007

Designing a complex system such as an LCD developing system becomes inefficient when many designers are involved and create their own parts even though they can be used repeatedly in other sections. Thus, this paper proposes a new design process that can maximize the number of common parts in complex system design by organizing the 3D design process. The proposed design process consists of 5 stages: analysis of design intention, definition of initial product structure, definition of skeleton model, sharing design intention with all assembles, control of correlation between components. The proposed design process can maximize common parts in design process, which results in shorter lead time, less production cost, and greater economic benefits.