• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.5
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• pp.72-79
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• 2000

On the other hand, the fiber orientation at the surface and middle layer of the sheet controls the bending stiffness of paperboard. Therefore, a reliable measurement of paper surface fiber orientation gives us a magnificent tool to investigate and predict paper curling and cockling tendency, and provides the necessary information to fine-tune the manufacturing process for optimum quality. Many papers, especially heavily calendered and coated grades, do resist liquid and gas penetration very much, being beyond the measurement range of the traditional instruments or resulting inconveniently long measuring time per sample. The increased surface hardness and use of filler minerals and mechanical pulp make a reliable, non-leaking sample contact to the measurement head a challenge of its own. Paper surface coating causes, as expected, a layer which has completely different permeability characteristics compared to the other layers of the sheet. The latest developments in sensor technologies have made it possible to reliably measure gas flow n well controlled conditions, allowing us to investigate the gas penetration of open structures, such as cigarette paper, tissue or sack paper, and in the low permeability range analyze even fully greaseproof papers, silicon papers, heavily coated papers and boards or even detect defects in barrier coatings! Even nitrogen or helium may be used as the gas, giving us completely new possibilities to rank the products or to find correlation to critical process or converting parameters. All the modern paper machines include many on-line measuring instruments which are used to give the necessary information for automatic process control systems. Hence, the reliability of this information obtained from different sensors is vital for good optimizing and process stability. If any of these on-line sensors do not operate perfectly as planned (having even small measurement error or malfunction), the process control will set the machine to operate away from the optimum, resulting loss of profit or eventual problems in quality or runnability. To assure optimum operation of the paper machines, a novel quality assurance policy for the on-line measurements has been developed, including control procedures utilizing traceable, accredited standards for the best reliability and performance.

• Journal of Korean Society for Quality Management
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• v.11 no.1
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• pp.44-50
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• 1983

The main factors of determining the Control Line of the Control Chart can be classified as follows: 1) sample size (n), 2) the factor that determines the spread of Control Limits (B), (3) sampling frequency (h). The determination of these factors can be explained according to the extent that occurrences of assignable cause should be detected. The purpose of this paper are two: one is for composing a model of which use should be designated for economic decision on the size of these factors leading to the Control Line of the Control Chart, the other is about what influence increasing or decreasing condition, according to changeability of the size of these factors, of expect cost can have on the economy when the Control Chart is used.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1993.10a
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• pp.31-39
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• 1993

This paper considers a procedure for the economic design of a cumulative score(CUSCORE) control chart and more sensitive than X-type control chart for small shift to control the mean of a process with a exponentially distributed quality characteristic. An expected loss - cost model as a function of design variables(sample size, sampling interval, scoring limit and decision limit) is derived. Direct search techniques are used to optimize the model subject to ARL in control. Numerical examples and sensitivity analysis of the model are presented. For selected values of situation parameters a comparison study with CUSUM charts is given. CUSCORE control charts compare favourably with CUSUM charts in cost for speedy production process. The proposed control chart can be directly applied for controlling the lifetime characteristics.

• Journal of Korean Society for Quality Management
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• v.23 no.4
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• pp.157-166
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• 1995

Process capability indices are used to determine whether a production process is capable of producing items within a specified tolerance. We could estimate the finite sample distributions of some process capability indices with bootstrap method. In this paper, we derive the asymptotic bootstrap distributions of some process capability indices ${\hat{C}}^*_p$, ${\hat{C}}^*_{pk}$ and ${\hat{C}}^*_{pm}$ under general proper conditions. These asymptotic distributiops would be used in constructing some bootstrap confidence intervals. Also, we examine some small sample properties related to these estimators by some simulations.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.11
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• pp.4449-4454
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• 2010

The principal objective of this study was to evaluate the physicochemical characteristics of scattered-flower ladybell powdered brown rice Dasik prepared with four kinds of sugars. We noted that the luminance of control sample was higher than that of BRSM and BRIM, but similar to BRFM sample. In Hunter's a of control were higher than those of BRFM and BRFM, but similar to BRSM sample. In Hunter's of b values were decreased. With regard to the mechanical properties of the Dasik samples, we noted significant differences in hardness, gumminess, chewiness but no differences in springiness and cohesiveness were detected. The hardness, gumminess, chewiness of control sample were lowered than those of BRSM and BRIM. The case of sensory evaluation, there were taste and texture of control sample were higher than those of BRSM and BRIM, but BRFM. And the overall quality of BRFM was significantly higher than those of BRSM and BRIM, but control sample.

• Food Science of Animal Resources
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• v.21 no.3
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• pp.227-234
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• 2001

This study was conducted to determine the effects of microperforated film on the quality and shelf-life improvements of pork bellies during cold storage. Samples were stored for 14 days at 0$\pm$1$^{\circ}C$ and 55$\pm$10% r.h.. The packaging treatments were the unpackaged sample as control, the wrapped sampled with microperforated polypropylene film(MPF) and unperforated PP film(PPF), respectively. After 10 days, the counts of all kinds of microorganisms investigated tended to be the lowest in the control samples, and followed by MPF and PPF. The 'a' value for PPF was significantly lower than the values for control and MPF at 14 day. The 'L' values for MPF measured after 10 days were significantly lower than those of PPF and higher than those for control. After 4 days of storage, the 'b' values for PPF showed significantly lower than those of MPF. As storage time elapsed, percent weight loss was the highest in the control samples followed by those from MPF and PPF. Sensory analyses showed that MPF samples tended to be evaluated higher in all parameters than the control and PPF samples after 7 days. It is concluded that microperforated film wrapping can be used efficiently for maintaining the quality of fresh pork bellies during cold storage and retail display.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.12
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• pp.1773-1780
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• 2013

This study was performed to compare physicochemical and sensory properties of cholesterol-removed Gouda cheese (CRGC) and Gouda cheese made in the laboratory during ripening. Composition, short-chain free fatty acids (SCFFA), texture, color, and sensory properties were measured. In chemical composition analyses, moistures were significantly different between control cheeses (42.86%) and sample cheese (48.32%) (p<0.05). But fat and protein in the control and the sample were 32.77, 22.45 and 31.35, 20.39%, respectively, and were not significantly different (p>0.05). The amount of cholesterol in control was 82.52 mg/100 g and the percentage of cholesterol removal was 90.7%. SCFFA increased gradually during ripening and its level of CRGC increased and significantly different from that of control (p<0.05). The texture, hardness, gumminess, and chewiness were significantly increased, but cohesiveness and springiness were not increased in both cheeses during ripening periods (p>0.05). In comparison of the control and sample cheeses, hardness, and springiness were not significantly different, but cohesiveness, gumminess, and chewiness were different (p<0.05). In color measurement, all color values were not different between CRGC and control (p>0.05). However, $L^*$ value decreased, while $a^*$ and $b^*$ values tended to increase significantly (p<0.05). In sensory properties, appearance, aroma, flavor and taste, and texture were significantly increased except buttery and nutty in aroma and sweetness in taste in both cheeses, and were not significantly different between the control and sample cheeses during ripening (p>0.05). Therefore, this study suggests that the quality of cholesterol-removed Gouda cheese is not different from the control cheese.

• The Korean Journal of Food And Nutrition
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• v.34 no.1
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• pp.15-25
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• 2021

This study aimed to investigate the antioxidant activities and quality characteristics of jelly added with Orostachys japonicus juice. The moisture content and the soluble solids content of the jelly samples decreased significantly with increasing content of O. japonicus. The pH was highest in the control samples, and the pH significantly decreased with the addition of increasing amounts of O. japonicus. In terms of the chromaticity measurements, the lightness value and redness value was highest in the control sample, and it decreased as the amount of added O. japonicus increased, whereas the yellowness value increased with increasing levels of O. japonicus added. The gumminess and chewiness of the jelly increased with the addition of increasing amounts of O. japonicus. On the other hand, the cohesiveness and adhesiveness of the jelly did not show statistically significant changes. The total polyphenol and DPPH radical scavenging activities of the jelly with 100% O. japonicus added were significantly higher than those of the jelly with 0% O. japonicus added. Regarding the sensory evaluation, the sample with 75% O. japonicus added was perceived to have the best color, flavor, O. japonicus flavor, chewiness, and overall preference.

• Journal of Korean Society for Quality Management
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• v.22 no.1
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• pp.66-81
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• 1994

Several sample statistics to simultaneously monitor both means and variances for multivariate quality characteristics under multivariate normal process are proposed. Performances of multivariate Shewhart schemes and cumulative sum(CUSUM) schemes are evaluated for matched fixed sampling interval(FSI) and variable sampling interval(VSI) feature. Numerical results show that multivariate CUSUM charts are more efficient than Shewhart charts for small or moderate shifts and VSI feature is more efficient than FSI feature.

• The Korean Journal of Nuclear Medicine Technology
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• v.21 no.1
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• pp.60-64
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• 2017

Purpose Westgard multi-rules application based on test quality improvement and commercialized international standard has been widely used in quality control. However, it is difficult to applicate the Westgard multi-rules in nuclear medicine in vitro tests due to the larger sample sizes and the simultaneous measurement of quality control material and patient sample. This study investigated the usefulness of Westgard multi-rules application in nuclear medicine in vitro tests. Materials and Methods A total of 282 systematic error multi-rules (22s, 101s) recorded in the samsung medical center computer system from January 2013 to June 2016 along with 117 cases of corrective measure record was analyzed. The Quality control implementation is recorded in Hospital information system were divided into 4 high-level areas including quality control material error, experimental procedural error, Kit lot number management error, and others. To prevent quality control material error, the existing method that each staff used their own method was changed. The staff who in charge of managing the quality control material was designated and daily consumption amount of every test was strictly controlled by one person. To prevent other errors, every test step was standardized so that the entire test procedures are identically implemented. Results The total quality control implementation was 117 cases; As a result, 62 quality control material errors were 62 cases, experimental process errors were 24 cases, Kit lot number control errors were 18 cases, and other errors were 13 cases. The quality control material error was corrected and could be used fresh materials within 2 days after thawing. The cases of systemic error were decreased to causes as quality control material error. The quality control materials were reduced above 10 vials to a monthly average. In addition, these errors of experimental processing and Kit lot number were improved by test standardization. Consequently, the cases of 101s and 22s in systematic error rules decreased at least 2 cases to a monthly average. Conclusion To confirm of systematic error through multi-rules application quickly, it is necessary to base on management of the QC material, target values and standard deviation. Moreover, in the event of a systematic error, it was found important to record measures based on test cause analysis. The experiment results are expected to contribute to internal quality control improvement and prompt and accurate result reporting through error recording and causal analysis based on Westgard multi-rules analysis.