• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.25 no.6
• /
• pp.48-53
• /
• 2002

품질보증 부분에서 대부분 통계적 수법들은 기지분포를 가정하여 데이터를 분석하고 있다. 예를 들면 공정능력에서는 정규분포를 가정하고 있고, 신뢰성 분석에서는 지수분포, 대수정규분포 또는 와이블분포 등을 가정하고 있다. 만약 이러한 것들이 가정하는 확률분포와 크게 편의될 때 도출된 결론은 그 유효성을 상실하게 된다. 따라서 공정이 정규분포를 하지 않는다면 정규분포에 기초한 공정능력지수의 사용은 부정확한 공정의 정보를 제시하게 된다. 이러한 문제를 해결하기 위하여 그 사례로 소표본일 경우 정규성의 유무를 Lilliefors 검정통계량으로 검정하였다. 그리고 최우추정량(MLE), 수정적률추정량(MME), 및 적률추정량(ME)을 사용하여 모수추정을 하여 그 각각의 경우에 공정능력지수로 평가하였다. 공정능력지수의 평가는 공정이 지수분포를 하는 경우에 적합한 공정능력지수($C_{pe}$)를 제안하고, 이것의 대안으로써 Pearson 시스템, Johnson 시스템 및 Burr 시스템과도 비교평가 하였다.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 2005.05a
• /
• pp.387-392
• /
• 2005

본 논문에서는 LCD 공정관리에서 SPC 시스템의 주요내용 및 운영방법론을 논하고자 한다. 주요내용으로는 실시간 프로세스 모니터링 방법론, 유의차분석 방법론, 이상데이터의 분석, 공정능력의 분석, 관리도 및 결과의 조회 등을 들 수 있다. 또한, TFT-LCD 공정을 크게 Fab 공정인 TFT 공정, LC 공정 및 Module 공정으로 나누어 각 공정에서의 중요한 특성과 관리방법론을 제시하고자 한다.

• Communications for Statistical Applications and Methods
• /
• v.18 no.3
• /
• pp.377-389
• /
• 2011

A higher quality level is generally perceived by customers as improved performance by assigning a correspondingly higher satisfaction score. The third generation index $C_{pmk}$ is more powerful than two useful indices $C_p$ and $C_{pk}$ that have been widely used in six sigma industries to assess process performance. In actual manufacturing industries, process capability analysis often entails characterizing or assessing processes or products based on more than one engineering specification or quality characteristic. Since these characteristics are related, it is a risky undertaking to represent the variation of even a univariate characteristic by a single index. Therefore, the desirability of using vector-valued process capability index(PCI) arises quite naturally. In this paper, we consider more powerful vector-valued process capability index $C_{pmk}$ = ($C_{pmkx}$, $C_{pmky}$)$^t$ that consider the univariate process capability index $C_{pmk}$. First, we examine the process capability index $C_{pmk}$ and plug-in estimator $\hat{C}_{pmk}$. In addition, we derive its asymptotic distribution and variance-covariance matrix $V_{pmk}$ for the vector valued process capability index $C_{pmk}$. Under the assumption of bivariate normal distribution, we study asymptotic confidence regions of our vector-valued process capability index $C_{pmk}$ = ($C_{pmkx}$, $C_{pmky}$)$^t$.

• Journal of the Korean Data and Information Science Society
• /
• v.24 no.3
• /
• pp.465-475
• /
• 2013

Higher quality level is generally perceived by customers as improved performance by assigning a correspondingly higher satisfaction score. Usually, the quality level is measured by process capability indices. The index is used to determine whether a production process is capable of producing items within a specified tolerance. Some useful process capability indices $C_p$, $C_{pk}$ and $C_{pm}$ have been widely used in six sigma industries to assess process performance. Most evaluations on process capability indices focus on point estimates, which may result in unreliable assessments of process performance. It is necessary to investigate their asymptotic correlationship among process capability indices $\hat{C}_p$, $\hat{C}_{pk}$ and $\hat{C}_{pm}$. In this paper, we study their asymptotic correlationship for some process capability indices $\hat{C}_p$, $\hat{C}_{pk}$ and $\hat{C}_{pm}$ under the normal process.

• Convergence Security Journal
• /
• v.7 no.2
• /
• pp.49-55
• /
• 2007

Software failure time presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing. For data analysis of software reliability model, data scale tools of trend analysis are developed. The methods of trend analysis are arithmetic mean test and Laplace trend test. Trend analysis only offer information of outline content. From the subdivision of this analysis, new attemp needs the side of the quality control. In this paper, we discuss process capability analysis using process capability indexs. Because of software failure interval time is pattern of nonnegative value, instead of capability analysis of suppose to normal distribution, capability analysis of process distribution using to Box-Cox transformation is attermpted. The used software failure time data for capability analysis of process is SS3, the result of analysis listed on this chapter 4 and 5. The practical use is presented.

• Journal of Korea Technology Innovation Society
• /
• v.19 no.1
• /
• pp.137-160
• /
• 2016

This study assesses the structure relationships between resource, product and process innovation capability, technology commercialization competence and performance of firms in Daedeok Innopolis. In particular, this study attempts to analyze technology commercialization competence that may be influenced by product and process capabilities. The development of the research model is based on the literature of resource-based view and the empirical studies of technology commercialization competence. The survey of 109 firms was conducted from January 5, 2015 through February 4, 2015. We investigate the role of a firm's technology commercialization competence in determining its performance by performing Partial Least Squares analysis. The results indicate that a firm's human resources and intangible resources lead to a higher level of its product and process innovation capabilities. This study, however, finds that a firm's tangible resources do not have significant effects on its product and process innovation capabilities. And the study finds evidence that firm's product and process capabilities have positive effects on its technology commercialization competence. The study also finds that a firm's technology commercialization competence is a driving force behind its performance, showing that its technology commercialization competence positively involves its performance. In addition the study finds that technology commercialization competence mediates the relationship between a firm's innovation capability and performance, indicating that the technology commercialization used as mediating variable positively affects its innovation performance.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.2
• /
• pp.321-328
• /
• 2019

A military shelter for communication and information is necessary to optimize the integrated combat ability of weapon systems in the network centric warfare. Therefore, the military shelter is required for EMI shielding performance. This study examines the stable measurement points for EMI shielding effectiveness of a military shelter for communication and information. The measurement points were found by analyzing the EMI shielding effectiveness measurement data with data mining technique and process capability analysis. First, a support vector machine was used to separate the measurement point that has stable EMI shielding effectiveness according to set condition. Second, this process was conducted with process capability analysis. Finally, the results of data mining technique were compared with those of process capability analysis. As a result, 24 measurement points with stable EMI shielding effectiveness were found.

• Journal of Energy Engineering
• /
• v.18 no.3
• /
• pp.175-190
• /
• 2009

This study examines the influence of scale economy, technology, financing capability and market competition on economic performance by value chain in Korean solar energy companies, using the multiple logistic regression analysis. The current profit ratio is analyzed to have been positively affected by financing capability, while negatively by market competition. The scale economy and technology are analyzed to have no statistical significance on the economic performance. The current profit ratio for companies creating higher value in the sourcing process is negatively affected by technology while positively by financial capability. The one in the manufacturing process is affected positively by technology and financing capability, and the one in the marketing process is affected positively by financing capability while negatively by market competition. The implications of this study are as follows: Korean solar energy industry is recommended i) to establish the specific innovation system for technology development, ii) to set up advanced financial system, iii) to carry out the fractal system, the manufacturing system through the network of the firms owning core competence per value chain.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.37 no.3
• /
• pp.419-427
• /
• 2013

The catalytic converters for automobile exhaust systems are manufactured by inserting a mat-wrapped substrate into a stainless steel can. A residual pressure that is too high will initiate a fracture in the substrate. In contrast, a residual pressure that is too low will fail to hold the substrate in the acceleration or deceleration phase. Both the process capability and mat pressure on the substrate are predicted while considering the effect of the statistical variation in the dimensions of the parts. The validity of the solutions is then confirmed. A program using EXCEL combines a finite element analysis and process capability analysis in one program.

• Journal of Industrial Technology
• /
• v.28 no.A
• /
• pp.149-153
• /
• 2008

$C_p$ and other process capability indices are used extensively in industry, However, They are inadequate and widely misused. In a practical application, process average ${\mu}$ is almost always drifted by various assignable causes in process. And control charts will not detect these shifts in process average. In this study, incorporating these undetected shifts, a new capability analysis method is introduced.