• 펄프종이기술
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• 제32권5호
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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.

• 품질경영학회지
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• 제11권1호
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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.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 1993년도 추계학술대회발표논문집; 서강대학교, 서울; 25 Sep. 1993
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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.

• 품질경영학회지
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• 제23권4호
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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.

• 한국산학기술학회논문지
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• 제11권11호
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• pp.4449-4454
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• 2010

본 연구는 모시대 분말을 첨가한 현미분말에 당의 종류를 달리하여 제조한 다식의 품질특성을 분석하였다. 명도(L값)의 경우 대조군인 꿀 첨가군과 물엿 첨가군은 같은 값을 나타낸 반면 플락토올리고당 첨가군과 이소말토올리고당 첨가군은 유사한 값을 보였다. 적색도(a값)의 경우는 플락토올리고당 첨가군과 이소말토올리고당 첨가군은 대조군에 비해 유의적으로 낮은 값을 보였다. 황색도(b값)에 있어서도 플락토올리고당 첨가군과 이소말토올리고당 첨가군은 대조군에 비해 유의적으로 높은 값을 나타내었다. 기계적 특성에서 탄성과 응집성은 유의적인 차이가 없었으나 경도, 검성, 씹힘성은 유의적인 차이가 있었다. 경도, 검성, 씹힘성은 BRSM과 BRIM보다 대조군이 낮게 나타났다. 관능평가 결과, 맛의 경우 꿀 첨가군, 플락토올리고당 첨가군은 비슷한 점수를 보였으나, 이소말토올리고당 첨가군과 물엿 첨가군은 꿀이나 플락토올리고당 첨가군에 비해 유의적으로 낮은 점수를 나타내었다. 조직감은 다른 첨가군에 비해 플락토올리고당 첨가군이 유의적으로 높은 값을 나타내었다. 전체적인 기호도의 경우 꿀 첨가군과 플락토올리고당 첨가군은 같은 값으로 이소말토올리고당과 물엿 첨가군에 비해 유의적으로 높은 점수 차이를 나타내었다.

• 한국축산식품학회지
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• 제21권3호
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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.

• 한국식품영양학회지
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• 제34권1호
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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.

• Asian-Australasian Journal of Animal Sciences
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• 제26권12호
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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.

• 품질경영학회지
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• 제22권1호
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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.

• 핵의학기술
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• 제21권1호
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• pp.60-64
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• 2017

검사의 질 향상과 국제표준화의 상용화 정도관리물질을 이용한 Westgard multi-rules 적용의 유용성은 이미 알려져 있다. 그러나 핵의학 체외검사의 특성상 정도관리물질과 환자검체의 동시 계측으로 인한 측정횟수의 증가에 따라 Westgard multi-rules법을 적용함에 있어 어려움이 있다. 이에 본 연구는 핵의학 체외검사에서 상용화 정도관리물질을 이용한 Westgard multi-rules 적용의 유용성과 보완, 개선을 통해 내부정도관리의 효율성 향상을 조사하였다. 2013년 01월부터 2016년 06월까지 삼성서울병원 핵의학과 체외검사실 통합의료시스템에 기록된 총 282건의 적용된 계통오차 multi-rules (22s, 101s)과 117건의 조치사항 기록을 분석하였다. 조치사항은 multi-rules 중 계통오차의 규칙이 적용 되었을 때 기록하는 원인분석으로 정도관리물질 오류, 실험과정 오류, 검사키트 로트번호 관리 오류, 기타 등 총 4개의 대분류로 구성하였다. Westgard multi-rules 적용을 통해 조치사항을 분석한 결과 정도관리물질 오류가 62건, 실험과정 오류가 24건, 검사키트 로트번호 관리오류가 18건, 기타 13건으로 분류되었다. 정도관리물질 오류를 방지하고자 개선사항으로 기존에 각 검사자마다 사용하던 방식을 담당자 지정 방식으로 변경하여 모든 검사의 하루 소비량을 분주하여 공동사용을 하였고, 나머지 오류를 방지하고자 검사 전후 모든 과정을 표준화 하여 검사실내 어느 검사자가 시행 하더라도 일원화할 수 있게 하였다. 정도관리물질 오류를 개선한 결과 해동 후 2일 이내 신선한 물질을 사용 가능하였고 같은 물질을 사용하는 검사끼리 비교가 가능해져 물질에 의한 오류인지 명확해짐으로 계통오차 발생원인이 정도관리물질 오류로 기록하는 건수가 줄어들었다. 또한 정도관리물질의 로트번호 변경 시 교체시기가 같아 관리가 용이해졌고, 물질 사용량의 감소로 경제적 효과를 얻을 수 있었다. 그리고 검사표준화 적용 후, 계통오차의 규칙인 22s와 101s의 발생건수가 개선 전 보다 월 평균 2건 이상 줄어드는 결과를 보였다. Multi-rules의 적용을 통한 계통오차의 빠른 확인을 위해 정도관리물질의 체계적인 관리와 목표값과 표준편자의 설정 및 관리가 바탕이 되어야하며, 계통오차 발생 시 검사의 원인분석을 통한 조치사항을 기록하는 것이 중요함을 확인하였다. 본 실험의 결과로 Westgard multi-rules 적용 분석을 통해 발생 오류의 기재와 원인을 효율적으로 분석함으로써 핵의학 검사 내부정도관리의 질적 향상과 정확하고 신속한 결과보고에 기여할 것으로 사료된다.