• Communications for Statistical Applications and Methods
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• 제22권5호
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• pp.519-530
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• 2015

The geometric chart has proven more effective than Shewhart p or np charts to monitor the proportion nonconforming in high-quality processes. Implementing a geometric chart commonly requires the assumption that the in-control proportion nonconforming is known or accurately estimated. However, accurate parameter estimation is very difficult and may require a larger sample size than that available in practice in high-quality process where the proportion of nonconforming items is very small. Thus, the error in the parameter estimation increases and may lead to deterioration in the performance of the control chart if a sample size is inadequate. We suggest adjusting the control limits in order to improve the performance when a sample size is insufficient to estimate the parameter. We propose a linear function for the adjustment constant, which is a function of the sample size, the number of nonconforming items in a sample, and the false alarm rate. We also compare the performance of the geometric charts without and with adjustment using the expected value of the average run length (ARL) and the standard deviation of the ARL (SDARL).

• 대한산업공학회지
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• 제22권1호
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• pp.17-36
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• 1996

An economic two-stage screening procedure is presented when both lower and upper specification limits are given on the performance variable. A screening variable which is highly correlated with the performance variable is used first to decide whether an item should be accepted, rejected, or undecided. The performance variable is then used to classify the undecided items. The two variables are assumed to be jointly normally distributed. A cost model is constructed on the basis of six cost components; inspection costs of screening and performance variables and costs caused by type I and type II misclassification errors related with lower and upper specification limits. Optimal cutoff values on the screening variable are determined so that the average outgoing quality exceeds a prespecified level. Solution methods are provided for both known-parameter and unknown-parameter cases.

• 산업경영시스템학회지
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• 제18권36호
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• pp.275-285
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• 1995

In recent years there has been increasing interest in the issue of process centering in manufacturing process, The traditional process capability indices Cp, Cpk and Cpu are used to provide measure of process performance, but these indices do not represent the issue of process centering. A new measure of the process capability index Cpm is proposed that takes into account the proximity to the target value as well as the process variation when assessing process performance. However, Cpm only considers acceptance cost for deviation from target value within specification limits, do not includes economic consideration for rejected items. This paper proposes flexible process performance measures that considered quadratic loss function caused by quality deviation within specification limits, rejection cost associated with the disposition of rejected items, and inspection cost. In this model disposition of rejected items are considered under perfect corrective procedures and the absence of perfect corrective procedures.

• 품질경영학회지
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• 제34권4호
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• pp.125-132
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• 2006

An adjusted control limit of the $\overline{X}$ chart is proposed for monitoring the continually improving processes. The continual improvement of the process implies the decrease of the process variance, which is represented by a logistic curve. The process standard deviation is estimated by the exponentially weighted moving average of the sample standard deviations from the past to the current times. The control limits are adjusted by the estimated standard deviation at every sampling time. The performance of the adjusted control limit is compared with that of the standard control limits for various cases of the decreasing speed and size of the variance. The results show that the $\overline{X}$ chart with the adjusted control limits provides better performances for monitoring the small and moderate shifts in continually improving processes.

• 산학경영연구
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• 제18권2호
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• pp.83-110
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• 2005

최근 공공부문에서 성과관리의 필요성이 강조되고 있다. 그 방법론 중 하나로 제안되고 있는 것이 균형성과표(BSC)에 의한 성과관리이다. BSC는 재무적 측면 뿐만 아니라 조직의 내부 프로세스와 구성원 역량, 그리고 고객의 관점 등에서 성과관리를 할 것을 제안하고 있다. 그동안 공공부문은 민간부문과 비교하여 성과측정 및 관리를 소홀히 해 왔던 것이 사실이다. 그 이유는 민간부문처럼 경쟁의 심화 및 지속적인 수익창출을 위한 성과주의 조직관리의 필요성이 공공부문에서는 제기되지 않았기 때문이다. 그러나 공공성 뿐만 아니라 효율성과 지속적인 혁신이 중요한 가치가 됨에 따라 성과지표의 선정 및 관리에 따른 성과향상이 중요해지기에 이르렀다. 본 연구는 공공부문에서 성과관리의 일환으로 제기되고 있는 BSC의 타당성을 검토하고 BSC의 도입이 공공부문의 인사관리에 어떠한 영향을 미치는지를 살펴보고자 한다. 나아가 공공부문의 바람직한 인사관리 방향성에 대하여 제안하고자 한다.

• Earthquakes and Structures
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• 제24권6호
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• pp.439-453
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• 2023

Older brick masonry structures generally suffer from low strength defects. Using a cement mortar layer (CML) or steel-meshed cement mortar layer (S-CML) to reinforce existing low-strength brick masonry structures (LBMs) is still an effective means of increasing seismic performance. However, performance indices such as lateral displacement ratios and skeleton curves for LBMs reinforced with CML or S-CML need to be clarified in performance-based seismic design and evaluation. Therefore, research into the failure mechanisms and seismic performance of LBMs reinforced with CML or S-CML is imperative. In this study, thirty low-strength brick walls (LBWs) with different cross-sectional areas, bonding mortar types, vertical loads, and CML/S-CML thicknesses were constructed. The failure modes, load-carrying capacities, energy dissipation capacity and lateral drift ratio limits in different limits states were acquired via quasi-static tests. The results show that 1) the primary failure modes of UBWs and RBWs are "diagonal shear failure" and "sliding failure through joints." 2) The acceptable drift ratios of Immediate Occupancy (IO), Life Safety (LS), and Collapse Prevention (CP) for UBWs can be 0.04%, 0.08%, and 0.3%, respectively. For 20-RBWs, the acceptable drift ratios of IO, LS, and CP for 20-RBWs can be 0.037%, 0.09%, and 0.41%, respectively. Moreover, the acceptable drift ratios of IO, LS, and CP for 40-RBWs can be 0.048%, 0.09%, and 0.53%, respectively. 3) Reinforcing low-strength brick walls with CML/S-CML can improve brick walls' bearing capacity, deformation, and energy dissipation capacity. Using CML/S-CML reinforcement to improve the seismic performance of old masonry houses is a feasible and practical choice.

• 한국콘텐츠학회논문지
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• 제17권8호
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• pp.406-413
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• 2017

이 연구의 목적은 국내에서 시행 중인 현행 지식재산권법이 무용공연작품을 창작할 때 발생하는 지식재산에 대한 법적용의 한계를 알아보는데 있다. 21세기 이후 무용작품이 현행지적재산 관련법에서 어떻게 보호되고 있으며, 그 법들이 가지는 한계를 문헌을 통해 연구하였다. 본 연구는 먼저, 무용작품에서 발생하는 지식재산을 보호할 가능성이 있는 현행법을 정리하고 둘째, 융 복합 현장에서 이루어지는 안무들을 고찰하였다. 셋째, 앞에서 언급된 지식재산권들이 가지는 한계를 정리하였다. 연구결과 무용지적재산을 보호할 수 있는 지적재산권인 저작권, 특허, 상표법, 영업비밀이 있었다. 연구결과, 공연예술은 융합 콘텐츠를 개발함에 있어서도 대중과 소통할 수 있는 새로운 양식을 개발하지만 새로운 양식은 정작 법으로 그 권리를 완벽히 보호받기 어려움이 있다. 본 연구는 국내 시행중인 지적재산권법 중 오늘날 행해지는 안무 즉 무용창작 과정에서 발생하는 지적재산들을 보호할 수 있는 현행법들을 알아보고, 그 한계를 요약 정리하는데 그 의의가 있다.

• Advances in concrete construction
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• 제8권4호
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• pp.295-304
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• 2019

The lateral displacement or drift may be the cause of the damage in the reinforced concrete (RC) columns under the seismic load. In many regulations, lateral displacement was limited according to the properties of columns. The design displacement limits may be represented indirectly through the material strain limits and the mechanical properties of columns. EUROCODE-8 and FEMA356 calculate displacement limits by taking into account the mechanical properties of columns. However, Turkey Building Earthquake Code (TBEC) determine displacement limits by taking into account the material strain limits. The aim of this study is to assess the seismic design codes for RC columns through an experimental study. The estimates of seismic design codes have been compared with the experimental results. It is observed that the lateral displacement capacities of columns estimated according to some seismic codes are not in agreement with the experimental results. Also, it is observed that TBEC is conservative in the context of the performance indicator of RC columns, compared to EUROCODE-8 and FEMA356. Moreover, in this study, plastic hinge length and effective stiffness of test elements were investigated.

• 한국경영공학회지
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• 제23권4호
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• pp.73-86
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• 2018

Most electric products produced during the manufacturing process are produced after design and mass production under a given control standard. In particular, the development phase should present the criteria for the production process by setting appropriate limits based on the performance being targeted. Even if the standard of performance is set considering the performance of the process, measuring the performance of the product after actual production results will cause nonconformities with the expected results. Among the performance of electrical products, Energy standards represented by energy consumption efficiency continue to be of importance, and are mandatory standards that correspond to national standards in most countries. Therefore, statistical quality control of these standards shall basically have a large number of test equipment for each product, ensure sufficient test time and continuous sampling of product samples. In the end, companies that produce and sell electric appliances are striving to control mass production at a great cost, but this is not acceptable. This study presents basic characteristics of the energy efficiency of electrical products and proposes and conducts a case study on statistical production control methods for performance variation across products under the standards about domestic and international regulations.

• Food Science and Biotechnology
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• 제18권6호
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• pp.1430-1434
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• 2009

The present study used the liquid extraction pretreatment method and developed a liquid chromatographyultraviolet detector (LC-UV) for the simultaneous determination of 14 sulfonamides (SAs) residues in porcine and chicken muscle. Linearity within a range of $50-150\;{\mu}g/kg$ was obtained with the correlation coefficient ($r^2$) of 0.9673-0.9997. The mean recovery of SAs was 55.9-109.7% (relative standard deviations; RSDs 1.7-17.3%) in porcine muscle and 52.8-112.4% (RSDs 2.3-16.9%) in chicken muscle. The limits of detection (LODs) and limits of quantification (LOQs) were 2-32 and $7-96\;{\mu}g/kg$ in porcine muscle, and 4-32 and $13-97\;{\mu}g/kg$ in chicken muscle, respectively. These values were lower than the maximum residue limits (MRLs) established by the European Union. The sum of all SAs residues present should be less than $100\;{\mu}g/kg$.