• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1309-1313
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• 2008

This paper suggests an example of modification of the durability test specifications of electronic control unit for an automotive system in phase of design validation. The basic concept to redefine the specifications of durability test is based on the Arrhenius relationship for accelerated temperature test and the modified Coffin-Manson model for temperature cycle test. The ambient temperature of the powered-event durability test is increased to reduce the required test time of the current specification. Furthermore, the holding time between the events to cool down the temperature of the components is shortened and the resultant temperature rise affects the durability of the components. Thus, the acceleration factor due to the increased temperature range of temperature cycle is also estimated by the modified Coffin-Manson model.

• Journal of the Korean Society of Clothing and Textiles
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• v.46 no.4
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• pp.704-722
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• 2022

Current studies validate the Body Positive Scale (BP Scale) as a self-assessment instrument that captures four dimensions of the positive body image construct. We developed and evaluated a 17-item BP Scale using two focus group interviews and four independent samples (n = 1,379) of Korean women who completed online survey questionnaires. We generated an initial pool of items via literature review, content validation with experts, and focus group interviews, subsequently refining the items through exploratory analysis (Study 1). We confirmed the BP Scale's underlying dimensions with young Korean female samples (Study 2, Study 4) and with a community sample (Study 3). We also examined the construct validity, internal consistency, and test-retest reliability over a six-week interval. Overall, the results supported that the four-factor BP Scale demonstrates adequate validity and reliability in measuring positive body image among Korean women. The BP Scale provides a method for researchers and practitioners to understand and assess individuals' positive body image in a multifaceted manner.

• International Journal of Aeronautical and Space Sciences
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• v.1 no.1
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• pp.13-20
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• 2000

The applications of CFD in the design process of a transonic civil transport at Korea Aerospace Research Institute (KARI) are outlined. Three Navier-Stokes solvers, developed at KARI with different grid approaches, are used to predict the aerodynamic coefficients and solve the flowfield of various configurations. Multi-block, Chimera, and unstructured grids are the approaches implemented. The accuracy of the codes is verified for the transonic flow about RAE wing/fuselage configuration. The multi-block code is used to provide the detailed data on the flowfield around a wall interference model with different test section sizes which will be used in establishing the wall interference correction method. The subsonic and transonic flowfields about K100-04A, one of the configurations of a 100-seater transport developed by KARI and Korea Commercial Aircraft Development Consortium (KCDC), are computed to predict the aerodynamic coefficients. The results for the subsonic flow are compared with those of wind tunnel test, and the agreement is found to be excellent. The interference effect of nacelle installation on the wing of K100-04A is also investigated using the unstructured grid method, and about 10% reduction in wing lift is observed. The accuracy of the three developed codes is verified, and they are used as an efficient tool in the design process of a transonic transport.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.04a
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• pp.974-979
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• 2008

A design process for the structure-borne noise in a passenger vehicle is presented. The proposed process is improved from the previous one. The major difference between the current and last ones is that most of the countermeasures should be developed before fixing a tool for structural parts. This is requested for QCDP(Quality, Cost, Delivery and Productivity) by the design engineers. The proposed one consists of 4 steps: Problem definition, Cause analysis, Development of counter-measure and Validation. Based on the general rule: divide and conquer, the complex problem can be simplified into a few critical sub-systems through the first step: Problem definition. Secondly, the critical causes can be identified for the critical sub-systems through the second step: Cause analysis. Thirdly, effective countermeasures are investigated and produced through the third step: Countermeasure development. The proposed countermeasures are finally validated in the forth step: Validation.

• Nuclear Engineering and Technology
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• v.52 no.12
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• pp.2852-2859
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• 2020

This paper deals with the simulation-based design optimization and experimental validation of the characteristics of an in-core silver Self-Powered Neutron Detector (SPND). Optimized dimensions of the SPND are determined by combining Monte Carlo simulations and analytical methods. As a first step, the Monte Carlo transport code MCNPX is used to follow the trajectory and fate of the neutrons emitted from an external source. This simulation is able to seamlessly integrate various phenomena, including neutron slowing-down and shielding effects. Then, the expected number of beta particles and their energy spectrum following a neutron capture reaction in the silver emitter are fetched from the TENDEL database using the JANIS software interface and integrated with the data from the first step to yield the origin and spectrum of the source electrons. Eventually, the MCNPX transport code is used for the Monte Carlo calculation of the ballistic current of beta particles in the various regions of the SPND. Then, the output current and the maximum insulator thickness to avoid breakdown are determined. The optimum design of the SPND is then manufactured and experimental tests are conducted. The calculated design parameters of this detector have been found in good agreement with the obtained experimental results.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.06a
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• pp.791-792
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• 2007

• Proceedings of the Korean Nuclear Society Conference
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• 1999.05a
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• pp.23-23
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• 1999

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.1307-1308
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• 2005

• Nuclear Engineering and Technology
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• v.49 no.7
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• pp.1537-1546
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• 2017

Many thermal-hydraulic tests have been conducted at the Korea Atomic Energy Research Institute for verification of the SMART (System-integrated Modular Advanced ReacTor) design, the standard design approval of which was issued by the Korean regulatory body. In this paper, the contributions of these tests to the standard design approval of SMART are discussed. First, an integral effect test facility named VISTA-ITL (Experimental Verification by Integral Simulation of Transients and Accidents-Integral Test Loop) has been utilized to assess the TASS/SMR-S (Transient and Set-point Simulation/Small and Medium) safety analysis code and confirm its conservatism, to support standard design approval, and to construct a database for the SMART design optimization. In addition, many separate effect tests have been performed. The reactor internal flow test has been conducted using the SCOP (SMART COre flow distribution and Pressure drop test) facility to evaluate the reactor internal flow and pressure distributions. An ECC (Emergency Core Coolant) performance test has been carried out using the SWAT (SMART ECC Water Asymmetric Two-phase choking test) facility to evaluate the safety injection performance and to validate the thermal-hydraulic model used in the safety analysis code. The Freon CHF (Critical Heat Flux) test has been performed using the FTHEL (Freon Thermal Hydraulic Experimental Loop) facility to construct a database from the $5{\times}5$ rod bundle Freon CHF tests and to evaluate the DNBR (Departure from Nucleate Boiling Ratio) model in the safety analysis and core design codes. These test results were used for standard design approval of SMART to verify its design bases, design tools, and analysis methodology.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.26 no.4
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• pp.241-246
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• 2013

From the numerical results of density-based topology design optimization, a CAD geometric model is constructed and fabricated using 3D printer to experimentally validate the optimal design. In the process of topology design optimization, we often experience checkerboard phenomenon and complicated branches, which could result in the manufacturing difficulty of the obtained optimal design. Sensitivity filtering and morphology methods are used to resolve the aforementioned issues. Identical volume fraction is used in both numerical and experimental models for precise validation. Through the experimental comparison of stiffness in various designs including the optimal design, it turns out that the optimal design has the highest stiffness and the experimental result of compliance matches very well with the numerical one.