• Journal of the Korean Data and Information Science Society
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• v.8 no.1
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• pp.31-39
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• 1997

we shall propose some Bayes estimators and some generalized maximum likelihood estimators for reliability of a two-unit hot standby system with perfect switch based upon a complete sample of failure times observed from the exponential model and compare the peformances of the proposed estimators in terms of mean squared error.

• Journal of Korean Society for Quality Management
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• v.19 no.1
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• pp.16-27
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• 1991

Propose three rank tests based on different kinds of ranking methods for comparing several treatments with a control in a randomized block experiment. Monte Carlo power simulation study is examined in some small sample sizes and configurations to recommend a better test for applications.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11c
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• pp.569-577
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• 2000

The position of tobacco leaves is affluence to the quality. To evaluate its quality, sample leaves was collected according to the position of attachment. In Korea, the position was divided into four classes such as high, middle, low and inside positioned leaves. Until now, the grade of standard sample was determined by human expert from korea ginseng and tobacco company. Many research were done by the chemical and spectrum analysis using NIR and computer vision. The grade of tobacco leaves mainly classified into 5 grades according to the attached position and its chemical composition. In high and low positioned leaves shows a low level grade under grade 3. Generally, inside and medium positioned leaf has a high level grade. This is the basic research to develop a real time tobacco leaves grading system combined with portable NIR spectrum analysis system. However, this research just deals with position recognition and grading using the color machine vision. The RGB color information was converted to HSI image format and the sample was all investigated using the bundle of tobacco leaves. Quality grade and position recognition was performed through well known general error back propagation neural network. Finally, the relationship about attached leaf position and its grade was analyzed.

• Culinary science and hospitality research
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• v.22 no.5
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• pp.1-12
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• 2016

This study was carried out for the improvement of nutrition and quality of streamed bread. For this purpose, brown rice liquid starter and brown rice sourdough were made and steamed bread was made with different amounts of starter addition followed by a measurement of its physicochemical and sensory characteristics. The pH of dough and titratable acidity tended to decrease significantly according to brown rice sourdough. In addition, the titratable acidity of the control group had significant different by samples. As for the volume of dough, there was no significant difference between the control sample and each sample, but after 15 minutes of fermentation, the volume increased the most in the control sample, with sample D having the least volume. As for volume and specific volume of steamed bread, sample B had the largest at 3.34 and each sample had significant differences based on fermentation time. As for diameter, sample B was the largest at 88.11 and sample D was the smallest at 79.04, with significant differences among samples. As for height of steamed bread, the control group was the highest at 42.91 and sample D was the lowest at41.87, with significant differences among samples. As for the cross-section structure of steamed bread, the porous of sample B, which had the largest volume and specific volume, was the largest with uniform texture and even distribution. L value tended to be higher in the added sampleroups than in the control sample. a value increased as brown rice sourdough increased, and b value was lower when volume and specific volume of the steamed bread increased, which showed a similar trend with that a L value. As for hardness, viscosity, and chewing capacity, sample D was the highest and sample B was the lowest, with significant differences among samples. As a result of measurement of overall preference, sample B had the highest preference with the highest preference in flavor, taste, appearance and texture, and D had the lowest preference with the lowest preference in taste, appearance and texture, with significant differences among samples.

• Journal of Korean Society for Quality Management
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• v.23 no.3
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• pp.45-56
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• 1995

The method of lot by lot quality protection for sampling inspection by variables is widely used in quality control. In case of sampling inspection being done repeatedly, one can use the information from the previous sampling inspection to improve current estimates. This article shows that empirical Bayes estimator is superior to the usual sample mean in repeated sampling inspection by variables.

• Journal of Korean Society for Quality Management
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• v.31 no.1
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• pp.132-141
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• 2003

As the technology has improved and demands of customers have varied, a lot of products are getting diverse and intricate. Consequently, the enterprise that produce products have to simultaneously consider the various variables for the very products. There are some scheme, such as Multivariate control chart and Demerit control chart, designed to simultaneously monitor the variables in the process. In this paper, we present an effective method for process control using the Demerit-CUSUM control chart in the process where nonconforming units or nonconformities are occured by various types. In addition, we show interpretation method for abnormal signal in order to quickly detect the assignable causes as Demerit-CUSUM control chart signals abnormality. we compare performance of Demerit control chart and Demerit-CUSUM control chart using example again used in the existing studies, and present result of performance accoriding to changing sample size and parameter.

• Journal of Fashion Business
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• v.18 no.5
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• pp.144-158
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• 2014

National Competency Standards(NCS) is to systemize the competency that is necessary for performing duties in industrial fields and to utilize synthetically duty, vocational education training, and qualification at the national level. The purpose of this study is to analyze the process of NCS development and verification, which systemizes competency units and competency unit elements through the analysis of duty in pattern field. It is to cultivate competent people to be able to promote the development of pattern industry ultimately through being a complementary to educational circles and industry then to give them practical knowledge that is demanded in the field. Furthermore, it is to be utilized as a fundamental data for reforming the system of duty competency evaluation so as to manage personnel career systematically and to improve their competency. Focus Group Interview(FGI) was adapted as the method of this study, which was proceeded 3 times, and validity of the drawn result is verified through expert questionnaire survey. Research result, which is competency units, is 10 as follows; Fit trend analysis, Analysis of sample garment Specification sheet, Pattern making for sample garment, Pattern making for manufacturing garment, Creation of sewing specification, Instruction of manufacturing technique, Sample garment Inspection for quality control, Grading, Calculation of the required material quantities, Quality control.

• Journal of Biosystems Engineering
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• v.41 no.2
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• pp.138-144
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• 2016

Purpose: Phosphorus is an essential element for water quality control. Excessive amounts of phosphorus causes algal bloom in water, which leads to eutrophication and a decline in water quality. It is necessary to maintain the optimum amount of phosphorus present. During the last decades, various studies have been conducted to determine phosphorus content in water. In this study, we present a comprehensive overview of colorimetric, electrochemical, fluorescence, microfluidic, and remote sensing technologies for the measurement of phosphorus in water, along with their working principles and limitations. Results: The colorimetric techniques determine the concentration of phosphorus through the use of color-generating reagents. This is specific to a single chemical species and inexpensive to use. The electrochemical techniques operate by using a reaction of the analyte of interest to generate an electrical signal that is proportional to the sample analyte concentration. They show a good linear output, good repeatability, and a high detection capacity. The fluorescence technique is a kind of spectroscopic analysis method. The particles in the sample are excited by irradiation at a specific wavelength, emitting radiation of a different wavelength. It is possible to use this for quantitative and qualitative analysis of the target analyte. The microfluidic techniques incorporate several features to control chemical reactions in a micro device of low sample volume and reagent consumption. They are cheap and rapid methods for the detection of phosphorus in water. The remote sensing technique analyzes the sample for the target analyte using an optical technique, but without direct contact. It can cover a wider area than the other techniques mentioned in this review. Conclusion: It is concluded that the sensing technologies reviewed in this study are promising for rapid detection of phosphorus in water. The measurement range and sensitivity of the sensors have been greatly improved recently.

• The Korean Journal of Food And Nutrition
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• v.35 no.2
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• pp.106-115
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• 2022

The purpose of this study was to examine the quality characteristics of byeolmijang prepared several roasted whole grain powders (oat, brown rice, black soybean, corn) for eight weeks. As the fermentation progressed, the pH decreased from 6.10~6.12 to 4.48~4.92 and the total acidity increased dramatically from 0.41~0.48% to 1.67~2.24%. There were no differences in the moisture content. The content of reducing sugar decreased, in particular, brown rice sample(C) decreased significantly than the other samples during fermentation. In color, L and b-value decreased all samples, whereas a-value showed a tendency to slightly increase. The total cell counts and lactic acid bacteria revealed an increasing tendency during fermentation. In case of the amino-type nitrogen contents, it increased significantly during the fermentation period, especially control sample (A) showed the highest content significantly. The total polyphenol of all samples increased in the fermentation period. ABTS and DPPH radical scavenging activities also increased, especially corn sample (E) had the highest levels. In by electronic tongue analysis, corn sample (E) revealed higher umami and sourness than the control. So, by adding roasted corn powder, it can enhance function and taste of byeolmijang.

• Journal of the Korean Data and Information Science Society
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• v.28 no.2
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• pp.451-459
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• 2017

There are many researches showing that when a process change has occurred, variable sampling intervals (VSI) control chart is better than the fixed sampling interval (FSI) control chart in terms of reducing the required time to signal. When the process engineers use VSI control procedure, frequent switching between different sampling intervals can be a complicating factor. However, average number of samples to signal (ANSS), which is the amount of required samples to signal, and average time to signal (ATS) do not provide any control statistics about switching performances of VSI charts. In this study, we evaluate numerical switching performances of multivariate VSI EWMA chart including average number of switches to signal (ANSW) and average switching rate (ASWR). In addition, numerical study has been carried out to examine how to improve the performance of considered chart with accumulate-combine approach under several different smoothing constant and sample size. In conclusion, process engineers, who want to manage the correlation coefficients of related quality variables, are recommended to make sample size as large and smoothing constant as small as possible under permission of process conditions.