• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.6
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• pp.132-139
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• 2012

It is generally needed to test durability and lifetime when we develop parts in new technology. In this paper, the accelerated degradation analysis methods are developed to test them. This study is presented robust model estimation method that is less affected by outlier in regresstion model estimation. In addition, the lifetime can be predicted by Degradation-stress relationship in stress level.

• The Korean Journal of Applied Statistics
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• v.8 no.2
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• pp.77-86
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• 1995

For the problem of testing the parallelism of two regression lines, a robust procedure is proposed and examined. The proposed test statistic is based on the one-step GM-estimators of slope parameters proposed by Song et al. (1994b). These GM-estimators used the Least Trimmed Squares estimates as an initial values so as to obtain high breakdown point. Through a small-sample Monte Carlo simulation the empirical levels and powers of the proposed test are compared with other tests under various error distributions.

• Interdisciplinary Bio Central
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• v.2 no.2
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• pp.4.1-4.6
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• 2010

The most common type of microarray experiment has a simple design using microarray data obtained from two different groups or conditions. A typical method to identify differentially expressed genes (DEGs) between two conditions is the conventional Student's t-test. The t-test is based on the simple estimation of the population variance for a gene using the sample variance of its expression levels. Although empirical Bayes approach improves on the t-statistic by not giving a high rank to genes only because they have a small sample variance, the basic assumption for this is same as the ordinary t-test which is the equality of variances across experimental groups. The t-test and empirical Bayes approach suffer from low statistical power because of the assumption of normal and unimodal distributions for the microarray data analysis. We propose a method to address these problems that is robust to outliers or skewed data, while maintaining the advantages of the classical t-test or modified t-statistics. The resulting data transformation to fit the normality assumption increases the statistical power for identifying DEGs using these statistics.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.29 no.8 s.239
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• pp.1093-1101
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• 2005

Hybrid mass damper systems have recently been introduced as a dynamic vibration absorber to exploit the benefits of both the conventional tuned mass damper system and the active control system. A hybrid system is programmed to function as either a conventional TMD or as an active system according to the wind conditions and the resultant building and damper mass vibration characteristics. This paper deals with the design of the robust controller for the control of the flexible box structure. The control algorithm was devised based on $H_2$(LQG) robust control logic with acceleration feedback and to improve the capability of the controller Kalman Filter was accepted for the system. To test the ability of the robust controller using the linear motor damper system, performance tests and simulations were carried out on the full-scale steel frame structure. Through the performance tests, it was confirmed that acceleration levels are reduced down.

• Journal of Information Processing Systems
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• v.13 no.5
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• pp.1213-1228
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• 2017

The pitch tracking of music has been researched for several decades. Several possible improvements are available for creating a good t-distribution, using the instantaneous robust algorithm for pitch tracking framework to perfectly detect pitch. This article shows how to detect the pitch of music utilizing an improved detection method which applies a statistical method; this approach uses a pitch track, or a sequence of frequency bin numbers. This sequence is used to create an index that offers useful features for comparing similar songs. The pitch frequency spectrum is extracted using a modified instantaneous robust algorithm for pitch tracking (IRAPT) as a base combined with the statistical method. The pitch detection algorithm was implemented, and the percentage of performance matching in Thai classical music was assessed in order to test the accuracy of the algorithm. We used the longest common subsequence to compare the similarities in pitch sequence alignments in the music. The experimental results of this research show that the accuracy of retrieval of Thai classical music using the t-distribution of instantaneous robust algorithm for pitch tracking (t-IRAPT) is 99.01%, and is in the top five ranking, with the shortest query sample being five seconds long.

• Journal of Korean Society for Quality Management
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• v.17 no.2
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• pp.70-80
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• 1989

A nonparametric test for testing the parallelism of regression lines against ordered alternatives is proposed. The proposed test statistic is based on a linear combination of robust slope estimators. It is a modified version of the Adichie's test statistics based on scores. A snail-sample Monte Carlo study shows that the proposed test is compatible with the Adichie's test.

• Journal of Institute of Control, Robotics and Systems
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• v.18 no.9
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• pp.878-886
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• 2012

This paper investigates the implementation and flight test of realtime vision guided autopilot system based on virtual instrumentation platform. A graphical design process via virtual instrumentation platform is fully used for the image processing, communication between systems, vehicle dynamics control, and vision coupled guidance algorithms. A significatnt ojective of the algorithm is to achieve an environment robust autopilot despite wind and an irregular image acquisition condition. For a robust vision guided path tracking and hovering performance, the flight path guidance logic is combined in a multi conditional basis with the position estimation algorithm coupled with the vehicle attitude dynamics. An onboard flight test equipped with the developed realtime vision guided autopilot system is done using the rotary UAV system with full attitude control capability. Outdoor flight test demonstrated that the designed vision guided autopilot system succeeded in UAV's hovering on top of ground target within about several meters under geenral windy environment.

• Journal of the Korean Statistical Society
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• v.11 no.2
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• pp.109-117
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• 1982

In this paper, a preliminary study is performed on the subset selection procedures which are based on the trimmed means and the Hodges-Lehmann estimator derived from the Wilcoxon test. The proposed procedures are compared to the Gupta's rule through a small smaple Monte Carlo study. The results show that the procedures based on the robust estimators are successful in terms of efficiency and robustness.

• Proceedings of the KIEE Conference
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• 1997.07b
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• pp.636-638
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• 1997

This paper deals with the problem of finding robust controller based upon a pole assignment method for a plant with parameter perturbations. This case is not a problem of Interval polynomial family but a problem of poly topic polynomial family. As a method of stability test, we used GKT(Generalized Kharitonov Theorem) having computational advantage.

• The Korean Journal of Applied Statistics
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• v.22 no.5
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• pp.1097-1102
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• 2009

Classification of subjects with unknown distribution in small sample size setup may involve order-restricted constraints in multivariate parameter setups. Those problems makes optimality of conventional likelihood ratio based statistical inferences not feasible. Fortunately, Roy (1953) introduced union-intersection principle(UIP) which provides an alternative avenue. Redescending M-estimator along with that principle yields a considerably appropriate robust testing procedure. Furthermore, conditionally distribution-free test based upon exact permutation theory is used to generate p-values, even in small sample. Applications of this method are illustrated in simulated data and read data example (Lobenhofer et al., 2002)