• Proceedings of the KSME Conference
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• 2001.06c
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• pp.327-332
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• 2001

An experimental design technique is developed for estimating the moments of system response functions. It is easy to implement and provides accurate results compared with other traditional methods. It is based on the work of Taguchi, later improved by D'Errico and Zaino. The existing experimental techniques, however, is applicable only for normally distributed cases. In this article the three-level Taguchi method is extended to obtain optimum choice for levels and weights to handle nonnormal distributions. A systematic procedure for reliability analysis is then proposed by using the Pearson system and the narrow system reliability bounds. Illustrative examples including a tolerance optimization problem are shown very accurate comparing with those by Monte-Carlo simulations and the first-order reliability method.

• Corrosion Science and Technology
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• v.20 no.2
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• pp.52-61
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• 2021

This study using experimental design and linear regression technique was implemented in order to predict the pitting potential of stainless steel in marine environments, with the target materials being AL-6XN and STS 316L. The various variables (inputs) which affect stainless steel's pitting potential included the pitting resistance equivalent number (PRNE), temperature, pH, Cl^- concentration, sulfate levels, and nitrate levels. Among them, significant factors affecting pitting potential were chosen through an experimental design method (screening design, full factor design, analysis of variance). The potentiodynamic polarization test was performed based on the experimental design, including significant factor levels. From these testing methods, a total 32 polarization curves were obtained, which were used as training data for the linear regression model. As a result of the model's validation, it showed an acceptable prediction performance, which was statistically significant within the 95% confidence level. The linear regression model based on the full factorial design and ANOVA also showed a high confidence level in the prediction of pitting potential. This study confirmed the possibility to predict the pitting potential of stainless steel according to various variables used with experimental linear regression design.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.8 s.251
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• pp.897-905
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• 2006

This study considers an experimental design of disturbance compensation control to improve stabilization performance of main battle tanks. An adaptive non-parametric design technique based on the Filtered-x Least Mean Square(FXLMS) algorithm is applied in the consideration of model uncertainties. The optimal compensator is designed by two-step design procedures: determination of frequency response function of the disturbance compensator which can cancel the disturbance of series of single harmonics by using the FXLMS algorithm and determination of the compensator polynomial which can fit the frequency response function obtained in the first step optimally by using a curve fitting technique. The disturbance compensator is applied to a simple experimental gun-torsion bar-motor system which simulates gun driving servo-system. Along with experimental results, the feasibility of the proposed technique is illustrated. Experimental results demonstrate that the proposed control reduces the standard deviation of stabilization error to 47.6% that by feedback control alone. The directional properties of the FXLMS Algorithm such as the direction of convergence and its convergence speed are also verified experimentally.

• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.1111-1113
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• 2005

This paper deals with optimal design technique to reduce torque of IPM BLDC motor having concentrated winding. Optimization process using experimental design method which is one of the design technique is explained. Finally, the validity of experimental design method is proved by the results between prototype and optimization model.

• Journal of Korean Society for Quality Management
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• v.21 no.1
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• pp.96-107
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• 1993

In parameter design Taguchi analyzed a statistic which he called signal-to-noise(SN) ratio by using the experimental design technique. However he gave no justification for using SN ratios in the optimization procedure of parameter design. In this paper we discuss the validity of such SN ratios as proper statistics to be analyzed in parameter design. Moreover, using the real empirical data we examine the appropriateness of SN ratios, and we explain how transformation technique can be applied in parameter design as an alternative method of analysis.

• Journal of the Ergonomics Society of Korea
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• v.12 no.2
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• pp.3-13
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• 1993

A psychophysical measurement technique called "magnitude estimation" was used to evaluate several interior design alternatives for a high speed train. Pas- senger activity, seat direction, and passenger age were manipulated by using a three factor within-subjects experimental design. During the experiment, two dependent measures, a line length and a numerical estimate for each alternative design were collected to validate the experimental procedures. The results showed that pasnger seats arranged in the same direction as the running direction of the train was favored nine times more than the opposite. Also, the subjects preferred listening to music in a coach train to the other activities such as reading newspaper, watching a movie, and resting. This paper demonstrates that a psychophysical technique can be sued in the design of a development process, especially when it is difficult to quantify design variables such as subjective opinion or preference, etc.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.1
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• pp.42-48
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• 2006

In this study, a repetitive response surface enhancement technique (RRSET) is proposed as a new system approximation method for the efficient multidisciplinary design and optimization (MDO). In order to represent the highly nonlinear behavior of the response with second order polynomials, RRSET introduces a design space transformation using stretching functions and repetitive response surface improvement. The tentative optimal point is repetitively included to the set of experimental points to better approximate the response surface of the system especially near the optimal point, hence a response surface with significantly improved accuracy can be generated with very small experimental points and system iterations. As a system optimizer, the simulated annealing, which generates a global design solution is utilized. The proposed technique is applied to several numerical examples, and demonstrates the validity and efficiency of the method. With its improved approximation accuracy, the RRSET can contribute to resolve large and complex system design problems under MDO environment.

• Journal of the Ergonomics Society of Korea
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• v.18 no.3
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• pp.87-103
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• 1999

The present study employed an experimental usability testing technique to explore cognitive engineering characteristics of WWW. Based on the results of our previous study which employed non-experimental methods such as questionnaire and heuristic evaluation method, this study used a behavioral performance-measurement technique to evaluate the usability of a domestic web-site design. Specifically, we revised the menu and document structure of the original 'Movie-Friend' site to solve the design problems which were extracted from the results of the heuristic evaluation method of our previous study. Exp. 1 compared the relative navigation efficiency of the original frame menu site and the revised pop-up toolbar site, and Exp. 2 compared the toolbar menu site and the revised frame site. As a result of Exp. 1, the revised pop-up toolbar site showed improved navigation efficiency compared to the original site, as indicated by the mean latency and the number of pathways to reach the target page. However, we found no performance difference between the frame site and toolbar site in Exp. 2.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.5
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• pp.818-823
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• 2010

Exploiting models and simulations are encouraged among the defense acquisition society, as now enforced by the Defense Aquisition Program Administration's regulations. They are useful and, sometimes, inevitable especially in an earlier phase of system development. Computer-simulation-based experimentation technique for the system operational performance analysis for a torpedo defense system is introduced in this paper. Problem definition for the torpedo defense system analysis and engineering efforts for models and simulations development are presented here, including defining measures of performance and effectiveness for the torpedo defense system, conceptual modeling for torpedo engagement and defense simulation, design of experimentation, design of simulator and experimentor, and hardware and software implementation of an analysis support tool - a system operations demonstration and experimentation simulator.

• Journal of Korean Physical Therapy Science
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• v.31 no.1
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• pp.1-15
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• 2024

Background: This study was conducted to apply active release techniques to male youth basketball players to help improve physical development and damage prevention and improve performance through improved balance and functional movement. Design: Randomized control trial. Methods: The subjects included 33 youth basketball players who were randomly assigned to the experimental group (n=17) and the control group (n=16). For the experimental group, the active release technique was applied to the hip muscles, calf muscles, posterior thigh muscles based on the distribution of injuries surveyed in youth basketball players in the Korean Basksetball League. The Y-balance test and the functional reach test (FRT) were used to assess balance and the Functional Movement Screen (FMS) was used to assess functional movement. Interventions were conducted twice a week for 4 weeks at 40 minutes per session. The experimental group was the active release technique group, and static stretching, a common exercise therapy technique, and self-myofascial release using a foam roller were applied for 20 minutes. The control group received general exercise therapy and placebo active release technique. The placebo active release technique applies pressure only. results:The experimental group showed a greater improvement in balance, as evidenced by the FRT, compared to the control group, which received general exercise treatment. However, there was no statistically significant difference in improvement between the 2 groups. In the case of the experimental group, the difference in the Y balance test before and after the intervention was larger than that of the control group, but there was no statistically significant difference. Significant improvement was found in functional movement, as evidence by the FMS, for the trunk stability test (p < 0.05), in-line lunge test (p < 0.05), rotational stability test (p < 0.05), total score (p < 0.05). Conclusion: In this study, the active release technique improved the balance and functional movement of young basketball players more than general exercise therapy. The application of the active release technique is therefore expected to assist in physical development, prevent damage, and improve the performance of youth basketball players.