• Journal of Power System Engineering
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• v.17 no.6
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• pp.108-114
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• 2013

This paper describes process optimization for thermal-sprayed Co-based self-flux alloy coating by Taguchi method. Co-based self-flux alloy coatings were fabricated according to $L_9(3^4)$ orthogonal array using flame spray process. Hardness test and wear test were performed, the results were analyzed by analysis of variance(ANOVA) considering a multi response signal to noise ratio(MRSN). From the results of ANOVA, the optimal combination of the flame spray parameters on Co-based self-flux alloy coating could be predicted. The calculated hardness and wear rate of the coatings by ANOVA were found to be close to that of confirmation experimental result.

• The Korean Journal of Applied Statistics
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• v.15 no.2
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• pp.405-414
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• 2002

We consider the problem of estimating the error variance of in a two-way mixed-effects ANOVA model using noninformative priors. First, we derive Jeffreys' prior, a reference prior, and matching priors. We then provide marginal posterior distributions under those noninformative priors. Finally, we provide graphs of marginal posterior densities of the error variance and credible intervals for the error variance in two real data set and compare these credible intervals.

• The Korean Journal of Applied Statistics
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• v.8 no.1
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• pp.75-87
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• 1995

Computer graphics approach is a powerful tool when we are to explore the effects of the change of a part of the data, or the effects of the alteration of the characteristics of the statistical model currently employed. The paper describes the methods to implement dynamic graphics for the process of analysis of variance, and the methods to graphically represent ANOVA type data. The paper the describes a dynamic graphics software developed by the author for two-way ANOVA model.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.3 no.1
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• pp.8-12
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• 2010

In this paper, we studied on AR model order decision for extraction of EMG median frequency by t-test and ANOVA and comparison of median frequency. And we extracted well-known parameters such as zero crossing rate(ZCR), low band energy(Band) and median frequency(MDF) from surface electromyogram (EMG). And we compared to evaluate themselves as measures for fatigue.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.2
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• pp.135-141
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• 2017

An experimental study of micro blasting for a rotating aluminum rod was conducted through the statistical analysis of ANOVA to obtain the effect of blasting conditions. The rotating equipment was designed and constructed with forward and backward moving for helical blasting, but rotation was used in this study. The blasting condition factors were the type of abrasive particle, nozzle diameter, pressure, standoff distance, injection time, etc. The width of the surface, the maximum depth of the sprayed surface, and ANOVA were analyzed by statistical analysis. The results showed that the contributions of the main factors were pressure, nozzle diameter, and injection particle.

• Knowledge Management Research
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• v.5 no.1
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• pp.57-67
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• 2004

An air traffic control organization will require knowledge management to keep competitive advantage. A traffic controllers are forced to share their tacit as well as explicit knowledge among their organization to get aircraft's safety and efficient operation. The purpose of this study is to examine which factors influence the air traffic controllers' intention of sharing knowledge for the case of Civil Aviation Safety Authority, Ministry of Construction and Transportation. An ANOVA analysis shows that a difference exists between ages in terms of open mindedness towards sharing knowledge, the search for new knowledge and the recognition of the importance of sharing knowledge.

• Architectural research
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• v.16 no.2
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• pp.75-80
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• 2014

Risks, uncertainties, and associated cost overruns are critical problems for construction projects. Cost contingency is an important funding source for these unforeseen events and is included in the base estimate to help perform financially successful projects. In order to predict more accurate contingency, many empirical models using regression analysis and artificial neural network method have been proposed and showed its viability to minimize prediction errors. However, categorical factors on contingency cannot have been treated and thus considered in these empirical models since those models are able to treat only numerical factors. This paper identified potential factors on contingency in transportation construction projects and evaluated categorical factors using the one-way ANOVA statistical method. Among factors including project work type, delivery method type, contract agreement type, bid award type, letting type, and geographical location, two factors of project work type and contract agreement type were found to be statistically important on allocating cost contingency.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.862-865
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• 2000

The object of this paper is to evaluate the surface roughness using the experimental equation of surface roughness, which is developed in turning by an orthogonal array method. $L_9{3^4}$ orthogonal array method, one of fractional factorial design has been used to study effects of main cutting parameters such as cutting speed, feed rate and depth of cut, on the surface roughness. And the analysis of variance (ANOVA)-test has been used to check the significance of cutting parameters. Using the result of ANOVA-test, the experimental equation of surface roughness, which consists of only significant cutting parameter - feed rate, has been developed. The coefficient of determination of this equation is 0.962.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.5
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• pp.121-128
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• 2012

The optimization of cooling system parameters for designing injection mold is very important to acquire the highest part quality. In this paper, the integration of computer simulations of injection molding and Analysis of Variance(ANOVA) with orthogonal array was used as a design tool to optimize the cooling system parameters aimed at minimizing the part warpage. The design optimizer was applied to find the optimum levels of cooling system parameters for a dustpan. This optimization resulted in more uniform temperature distribution over the part and significant reduction of a part warpage, showing the capability of present method as an effective design tool. The whole optimization process was performed systematically in a proper number of cooling simulations. The design optimizer can be utilized effectively in the industry practice for designing mold cooling system with less cost and time.

• Communications for Statistical Applications and Methods
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• v.5 no.1
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• pp.85-97
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• 1998

완전확률화모형 및 랜덤화블럭모형하에서의 주요한 다중비교 분석기법들을 시뮬레이션을 이용하여 검토하고자 하였다. 시뮬레이션 결과는 순위변환과 최소유의차검정을 이용한 다중비교 분석기법이 모수적 ANOVA F 검정과 Fisher의 유의차검정, 비모수적 Kruskal-Wallis 검정과 최소유의차검정 및 Friedman 검정과 최소유의차검정을 이용한 분석기법보다 전체실험오차율, 전체실험검정력 및 개별쌍검정력 면에서 상대적으로 뛰어남을 보여준다. 즉 순위변환한 ANOVA F 검정의 전체실험오차율은 명목상의 유의수준을 잘 유지하고 있으며, 전체실험검정력 및 개별쌍검정력은 모수적 ANOVA F 검정과 Kruskal-Wallis 검정 및 Friedman 검정기법보다 전반적으로 우수함을 알 수 있다.