• Journal of KIISE:Computing Practices and Letters
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• v.12 no.2
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• pp.111-118
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• 2006

In this thesis, we analyze the efficiency of the algorithm to distribute the load in the clustered system, by comparing with the existed algorithm. PWLC algorithm detects each server's load in the system at weighted period, and following the detection of the loads, a set of weights is given to each server. The system allocates new loads to each server according to its weight. PWLC algorithm is compared with DWRR algorithm in terms of variance, waiting time by varying weighted Period. When the weighted period is too short, the system bears a heavy load for detecting load over time. On the other hand, when the weighted period is too long, the load balancing control of the system becomes ineffective. The analysis shows PWLC algorithm is more efficient than DWRR algorithm for the variance and waiting time.

• IE interfaces
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• v.18 no.4
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• pp.444-453
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• 2005

The purpose of the Gage R&R study is to determine whether a measurement system is adequate for monitoring a process. If the measurement system variation is small relative to the process variation, then the measurement system is deemed "adequate". The sources of variation associated with the measurement system are compared using an analysis of variance (ANOVA) model, in general. A typical ANOVA model used in a standard Gage R&R study is the two-factor random effect model. Then, the ANOVA partitions the total variation into three categories: repeatability, reproducibility, part variation. However, if the process variation possesses the between group variation, within group variation, and within part variation, these variations can cause the measurement system evaluation to provide misleading results. That is, in the standard Gage R&R study these variations affect the estimate of repeatability, reproducibility, or both. This paper presents a four-factor nested factorial ANOVA model which explicitly considers these variations for the Gage R&R study. The variance component estimators are derived by setting the EMS equations equal to the corresponding mean square from the ANOVA table and solving. And the proposed model is compared with the standard Gage R&R model.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1797-1802
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• 2005

In this study, we were developed an accuracy of the proposed two dimensional statical inclinometer what used a position sensitive detector(PSD) by an error analysis. The inclinometer consists of a laser source, a mass, an optic-fiber, and a PSD. The gravity direction on a base platform of the inclinometer is changed by an unknown inclination angle. And a laser spot is moved from the origin to another position of a PSD following a variation of an optical path by the gravity. These processes enable the inclinometer to estimate the inclination angle from distance information of the moving spot. A design methodology on the basis of a sensitivity analysis was applied to improve the measurement performance such as a full measuring range and a resolution. But it still has error factors, so we analyze the uncertainty of the inclinometer to evaluate the systematic errors from alignments, assembly error and so on. The experimental performance evaluation about the design objectives as a measuring range and a resolution was performed. And the validity and the feasibility of the design process were certified by an experimental process. Systematic errors eliminated to improve the accuracy of the inclinometer by the corrected measuring model from the calibration process between the inclination angle and the PSD position instead of the nominal measuring model. The ANOVA(analysis of variance) confirmed the effect of eliminating the systematic errors in the inclinometer. From these methodologies, the proposed inclinometer was able to measure with a high resolution(35.14sec) and a wide range(from $-15^{\circ}\;to\;15^{\circ}$

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2005.05a
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• pp.975-982
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• 2005

The purpose of the Gage R&R study is to determine whether a measurement system is adequate for monitoring a process. If the measurement system variation is small relative to the process variation, then the measurement system is deemed 'adequate'. The sources of variation associated with the measurement system are compared using an analysis of variance (ANOVA) model, in general. A typical ANOVA model used in a standard Gage R&R study is the two-factor random effect model. Then, the ANOVA partitions the total variation into three categories: repeatability, reproducibility, part variation. However, if the process variation possesses the between group variation, within group variation, and within-part variation, these variations can cause the measurement system evaluation to provide misleading results. That is, in the standard Gage R&R study these variations affect the estimate of repeatability, reproducibility, or both. This paper presents a four-factor nested factorial ANOVA model which explicitly considers these variations for the Gage R&R study. The variance component estimates are derived by setting the EMS equations equal to the corresponding mean square from the ANOVA table and solving. And the proposed model is compared with the standard Gage R&R model.

• Journal of the Korean Society of Propulsion Engineers
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• v.24 no.2
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• pp.43-51
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• 2020

After the accelerated aging, the bulkhead initiator using high explosives was carried out to verify aging characteristics. The Thru-Bulkhead Initiator operates by transmitting shock-wave generated from micro-initiator to the acceptor and the ignition explosives through the bulkhead. In order to evaluate the life-time of the product, the accelerated aging condition was set according to the life-time, and the ignition performance of the sample was measured every 10 cycles by measuring the delay time and the maximum pressure through the 10cc closed bomb test. In addition, variance analysis was used to determine aging.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.5
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• pp.2859-2869
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• 2014

The present study aims to examine job satisfaction and stress in relation to features of jobs taken by nursing assistants. The subjects for study are 469 nursing assistants active at work in various medical clinics and hospitals in Seoul Metropolitan City, engaged in a study conducted from May 1, 2013 through September 4, 2013. The positive analysis was verified at a significance level of five percent, and SPSS/WIN18.0 was used for statistics process. The analysis of frequency, t-test, one-way analysis of variance, and multiple regression analysis were conducted, and was then analyzed by multiple range test for statistics. The analysis reveals that job satisfaction level marks significant variance in accordance to the year of nursing assistant certificate acquired, age, and their final academic backgrounds. As to the job satisfaction variances in accordance to job features, the location of working places, fields of jobs, and the mode of jobs mark the highest. The study indicates that standardized directions for tasks in specific fields of jobs and education programs should be implemented for consistent management are requisite for improved efficiency of nursing assistants and professional nursing workforce.

• Korean Journal of Food Science and Technology
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• v.49 no.1
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• pp.35-43
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• 2017

The sensory characteristics of 12 commercial top-fermented beers were determined by sensory descriptive analysis. Beer samples were also analyzed for soluble solids, titratable acidity, pH, reducing sugar content, bitterness unit (BU), turbidity, hunter color values, amino acid content, total phenolic content, and DPPH radical scavenging activity. Five appearance, nine aroma, six flavor/taste, and four mouth-feel related sensory attributes were evaluated by a panel of nine judges. As the result of three way analysis of variance of descriptive data, all sensory attributes except "cereal" aroma and "salty" taste showed significant differences among the beers (p<0.05). Based on the principal component analysis of the descriptive data, samples were primarily separated by first and second principal components, which accounted for 78% of the total variance between the beers with high intensities of "yellow color", "caramel aroma", and "barley taste" versus "hop aroma", "sour", and "citrus aroma". In the correlation analysis between the sensory terms and physicochemical parameters, BU, total phenolic content, titratable acidity, soluble solids, and yellowness ($b^*$) showed significant positive correlations with citrus aroma, pineapple aroma, and fresh aroma characteristics.

• Journal of Korean Society of Transportation
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• v.23 no.5 s.83
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• pp.83-92
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• 2005

The purpose of the paper is to analyze an effectiveness before and after implementation of the median arterial bus lanes operation. The paper includes a speed analysis based on the Downs-Thomson Paradox theory, and a reliability analysis based on variance analysis of arrival time. According to the speed analysis, some road sections are now under phase 2 according to the Downs-Thomson Paradox, which is a state in which the bus speeds are greater than the car speeds. In the future it is predicted that cars and buses will reach an equilibrium speed which is in phase 3 of the multi-modal equilibrium theory. According to the reliability analysis of arrival time at each bus stop, in roads of median arterial bus lanes. the variance of arrival time is generally smaller than after the scheme implemented in eight months later.

• The Journal of the Korea Contents Association
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• v.21 no.3
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• pp.664-675
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• 2021

This study is to analyze the selection criteria for street dance institutes in the subjects of ordinary people and students majoring in street dance who select the institutes. Moreover, it aims to enhance the perception and values of street dance and to provide with the required data for the development of institutes that train street dance. To do so, a survey was conducted in the subjects of 300 street dance learners who went to the street dance institutes. Frequency analysis, reliability test, correlation analysis, and one-way analysis of variance (ANOVA) were performed using SPSS 18.0 Program with the collected data, and the results are as follows. In summary, training programs, services, and promotional environment were identified to be important criteria to select the street dance institutes by the learners while the low level of perception on the price was found.

• The Korean Journal of Applied Statistics
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• v.17 no.2
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• pp.281-301
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• 2004

In this paper we consider the change point problem in a sequence of univariate normal observations. We want to know whether there is any change point or not. In case a change point exists, we will identify its change type. Namely, it can be a mean change, a variance change, or both the mean and variance change. The intrinsic Bayes factors of Berger and Pericchi (1996, 1998) are used to find the type of optimal change model. The Gibbs sampling including the Metropolis-Hastings algorithm is used to estimate all the parameters in the change model. These methods are checked via simulation and applied to the winter average temperature data in Seoul.