• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.8
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• pp.1623-1630
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• 2002

Recently, much attention is imposed on the design of the fuel assemblies in the Pressurized Light Water Reactor (PWR). Spacer grid is one of the main structural components in a fuel assembly. It supports fuel rods, guides cooling water, and maintains a coolable geometry from the external impact loads. In this research, a new shape of the spacer grid is designed by the axiomatic approach. The Independence axiom is utilized for the design. For conceptual design, functional requirements (FRs) are defined and corresponding design parameters (DPs) are found to satisfy FRs in sequence. Overall configuration and shapes are determined in this process. Detail design is carried out based on the result of the axiomatic design. For the detail design, the system performances are evaluated by using linear and nonlinear finite element analysis. The dimensions are determined by optimization. Some commercial codes are utilized for the analysis and design.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.300-304
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• 2007

The reactor head structure assembly(RHSA) is the structure located on the reactor assembly. The purpose of the assembly is providing interface location for cables, preventing pipe whips, prohibiting instruments from becoming missiles, and restraining CEDMs' horizontal motion. On the RHSA, reactor disconnect panels(RDP) are installed. The installation location of RDP is to be decided to minimize the geometric interface with other components. Since the neighborhood of RHSA is crowded due to many connectors and cables, it is necessary to find the good design of RHSA to make an intricate situation attenuated and the required function maintained. The geometric shape and overall configuration of RHSA are determined by axiomatic design approach. The FRs of RHSA are specified and the corresponding DPs are found to satisfy FRs in sequence. The finite element analysis is carried out based on the result of the axiomatic design to evaluate the structural integrity.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.6
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• pp.127-133
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• 2003

NSD(No Spin Differential) has been developed fer a military truck. A benchmarking study for USA and Russian NSD has been carried out. Axiomatic approach has been applied for improving the design. A test code for NSB has been developed and applied to the developed sample. In the test results of comparing the developed sample with the USA imported sample, three major characteristics-the noise, mobility and steerability - are in the range of the intended target. A practical process for the evolution design is proposed.

• Transactions of the Korean Society of Automotive Engineers
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• v.7 no.6
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• pp.106-114
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• 1999

Today, one of the most important objective in automobile development is to reduce the weight of automobile . The eventual depletion of petroleum and environmental regulations brought considerable emphasis to this area on increasing fuel efficiency. Conventional intake air-fuel system is very heavy because it is composed of numerous parts. The bulky size caused increase in the amount of metal being used to build automobile chassis and this became a serious weight problem. The size also caused difficulties in optimization of fuel supply system which in turn decreased engine efficiency. Currently , there are efforts to integrate several intake system modules into one. The purpose of this paper is to evaluate the directions of such development.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.1
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• pp.195-200
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• 2001

There is a great demand for reducing the amount of material used in mass-produced plastics parts, for material cost constitutes up to 75% of the total production cost. Plastics do not easily decay which causes environmental problem. Furthermore, material reduction therefore decreases the amount of oil needed for the manufacture of plastics and thus help conserve this natural resource. Therefore, microcellular foamed plastics(MCPs) was developed at MIT to solve these problem alternation 1980's. Until now, however, microcellular foaming process not designed systematically because the key factors governing the process were not clear. The goal of this research is to obtain the optimal design of the microcellular plastics by using axiomatic approach.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.4
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• pp.1333-1346
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• 1996

As the automation system in manufacturing field works more efficientely, the automation scheme is applied to many areas. In order to reduce the entire manufacturing, cost the design process must be automated. However, design process is so complicated, it is very difficult to construct the design automation system. The axiomatic approach to design provides a general theoretical framework for all design fields, including mechanical design. The key concepts of axiomatic design are : the existence of domains, the characteristic vectors within the domains that can be decomposed into hierarchies through zigzagging between the domains, and the design axioms. Using this approach, the glass bulb design process was analyzed and the design automation software was developed. Through menu display, a user can select or furnish the design input and generate the drawing with ease.

• Research in Mathematical Education
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• v.7 no.1
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• pp.1-10
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• 2003

This research reviewed literatures on proof in mathematics education. Several views of proof can be classified (and identified) such as psychological approach (Platonism, empiricism), structural approach (logicism, formalism, intuitionism) and social approach (ontology, axiomatic systems). All these views of proof are valuable in mathematics education society. The concept of proof can be found in the form of analytic knowledge not of constructive knowledge. Human beings developed their knowledge in the sequence of constructive knowledge to analytic knowledge. Therefore, in mathematics education, the curriculum of mathematics should involve the process of cognitive knowledge development.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.31 no.1 s.256
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• pp.62-69
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• 2007

Micromanipulator is a device that manipulates an object with high precision. Generally, a parallel-type robot has inherently higher precision than a serial-type robot. In most cases, the use of flexure hinge mechanisms is the most appropriate approach to micromanipulators. The micromanipulator is basically required that have high natural frequency and sufficient workspace. However, previous designs are hard to satisfy the required workspace and natural frequency, simultaneously, because the previous micromanipulators are coupled designs. Therefore, this paper suggests a new design parameter as displacement amplifier and new design procedure based on semi-coupled design in axiomatic design. As a consequence the spatial 3-DOF micromanipulator which is chosen as an exemplary device has natural frequency of 500Hz and workspace of $-0.5^{\circ}{\sim}0.5^{\circ}$. To investigate the effectiveness of the displacement amplifier, simulation and experiment are performed.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1028-1033
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• 2008

The mount type HVAC control system is a type of an HVAC control system which is installed between a ceiling and ceiling boards of a room to control room temperature. Although the device is quite popular, design is conducted by a conventional way where engineering intuition and experiences are utilized. It is found that the design process is fairly inefficient and time-consuming because there are a lot of feedbacks. The axiomatic approach is used to investigate the design characteristics of the mount type HAVC control system and the Independence Axiom is utilized for the investigation. The Overall hierarchy is established up to the level of parts. It is found that the current design has many coupled and redundant aspects. The hierarchy is reorganized based on the Independence Axiom and a new design process is found. To exploit the new design process in practice, a design manual is made.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.6
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• pp.101-109
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• 2005

Ultra-precision positioning systems basically require high natural frequency and sufficient workspace. To cope with this requirement, flexure hinge mechanisms have been proposed. However, previous designs are hard to satisfy the functional requirements of the system due to difficulty in modeling and optimizing process applying an independent axiomatic design. Therefore, this paper proposes a new design and design-order based on semi-coupled axiomatic design. A planar 3 DOF parallel type micro mechanism is chosen as an exemplary device. Based on preliminary kinematic analysis and dynamic modeling of the system, an optimal design has been carried out. To check the effectiveness of the optimal parameters obtained from theoretical approach, simulation is performed by FEM. The simulation result shows that a natural frequency of 200.53Hz and a workspace of $2000{\mu}m{\times}2000{\mu}m$ can be ensured, which is in very close agreement with the specified goal of design.