• Title/Summary/Keyword: Average run length

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Development of Computer Vision System for Individual Recognition and Feature Information of Cow (I) - Individual recognition using the speckle pattern of cow - (젖소의 개체인식 및 형상 정보화를 위한 컴퓨터 시각 시스템 개발 (I) - 반문에 의한 개체인식 -)

  • 이종환
    • Journal of Biosystems Engineering
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    • v.27 no.2
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    • pp.151-160
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    • 2002
  • Cow image processing technique would be useful not only for recognizing an individual but also for establishing the image database and analyzing the shape of cows. A cow (Holstein) has usually the unique speckle pattern. In this study, the individual recognition of cow was carried out using the speckle pattern and the content-based image retrieval technique. Sixty cow images of 16 heads were captured under outdoor illumination, which were complicated images due to shadow, obstacles and walking posture of cow. Sixteen images were selected as the reference image for each cow and 44 query images were used for evaluating the efficiency of individual recognition by matching to each reference image. Run-lengths and positions of runs across speckle area were calculated from 40 horizontal line profiles for ROI (region of interest) in a cow body image after 3 passes of 5$\times$5 median filtering. A similarity measure for recognizing cow individuals was calculated using Euclidean distance of normalized G-frame histogram (GH). normalized speckle run-length (BRL), normalized x and y positions (BRX, BRY) of speckle runs. This study evaluated the efficiency of individual recognition of cow using Recall(Success rate) and AVRR(Average rank of relevant images). Success rate of individual recognition was 100% when GH, BRL, BRX and BRY were used as image query indices. It was concluded that the histogram as global property and the information of speckle runs as local properties were good image features for individual recognition and the developed system of individual recognition was reliable.

Statistical Design of X Control Chart with Improved 2-of-3 Main and Supplementary Runs Rules (개선된 3 중 2 주 및 보조 런 규칙을 가진 X관리도의 통계적 설계)

  • Park, Jin-Young;Seo, Sun-Keun
    • Journal of Korean Society for Quality Management
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    • v.40 no.4
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    • pp.467-480
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    • 2012
  • Purpose: This paper introduces new 2-of-3 main and supplementary runs rules to increase the performance of the classical $\bar{X}$ control chart for detecting small process shifts. Methods: The proposed runs rules are compared with other competitive runs rules by numerical experiments. Nonlinear optimization problem to minimize the out-of-control ARL at a specified shift of process mean for determining action and warning limits at a time is formulated and a procedure to find two limits is illustrated with a numerical example. Results: The proposed 2-of-3 main and supplementary runs rules demonstrate an improved performance over other runs rules in detecting a sudden shift of process mean by simultaneous changes of mean and standard deviation. Conclusion: To increase the performance in the detection of small to moderate shifts, the proposed runs rules will be used with $\bar{X}$ control charts.

CUSUM control chart for Katz family of distributions (카즈분포족에 대한 누적합 관리도)

  • Cho, Gyo-Young
    • Journal of the Korean Data and Information Science Society
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    • v.22 no.1
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    • pp.29-35
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    • 2011
  • In statistical process control, the primary method used to monitor the number of nonconformities is the c-chart. The conventional c-chart is based on the assumption that the occurrence of nonconformities in samples is well modeled by a Poisson distribution. When the Poisson assumption is not met, the X-chart is often used as an alternative charting scheme in practice. And CUSUM-chart is used when it is desirable to detect out of control situations very quickly because of sensitive to a small or gradual drift in the process. In this paper, I compare CUSUM-chart to X-chart for the Katz family covering equi-, under-, and over-dispersed distributions relative to the Poisson distribution.

Wood Quality of Populus nigra × maxmowiczii. (I) - Variation of Bulk Density, Wood Fiber Dimension, Microfibril Angle, and Number of Leaf Knot within Stem - (양황철나무의 재질(材質) (I) 용적밀도수(容積密度數), 목섬유(木纖維)치수 및 잎옹이 분포수(分布數)의 간내변수(幹內變數) -)

  • Park, Sang-Jin;Kang, Sun-Gu;Lee, Ki-Yeong;Jo, Jae-Myeong
    • Journal of the Korean Wood Science and Technology
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    • v.18 no.3
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    • pp.26-33
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    • 1990
  • To study the wood quality factors of Populus nigra $\times$ maxmowiczii known a rapidly growing species, the variations of green moisture contents, bulk density, wood fibre dimensions, microfibril angles, and number of leaf knot in stem wood were investigated. The heartwood contained a higher moisture content than the corresponding sapwood. Bulk density in radial patterns variations decrease outward from the pith, then increase toward the bark. The wood-fiber length and diameters had somewhat smaller values than on Populus alba $\times$ glandulosa or Populus euramericana. The microfibril angles decreased rapidly toward the outside, and their mean values were about 16 degree. The grain angles run nearly parallel to the cell axies. Number of leaf knot showed a fluctural change above ground level to a point near the base of the crown and then increased rapidly to the top of tree and average number of leaf knot varied exclusively from tree to tree.

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A Study on the Alternative ARL Using Generalized Geometric Distribution (일반화 기하분포를 이용한 ARL의 수정에 관한 연구)

  • 문명상
    • Journal of Korean Society for Quality Management
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    • v.27 no.4
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    • pp.143-152
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    • 1999
  • In Shewhart control chart, the average run length(ARL) is calculated using the mean of a conventional geometric distribution(CGD) assuming a sequence of identical and independent Bernoulli trials. In this, the success probability of CGB is the probability that any point exceeds the control limits. When the process is in-control state, there is no problem in the above assumption since the probability that any point exceeds the control limits does not change if the in-control state continues. However, if the out-of-control state begins and continues during the process, the probability of exceeding the control limits may take two forms. First, once the out-of-control state begins with exceeding probability p, it continues with the same exceeding probability p. Second, after the out-of-control state begins, the exceeding probabilities may very according to some pattern. In the first case, ARL is the mean of CGD with success probability p as usual. But in the second case, the assumption of a sequence of identical and independent Bernoulli trials is invalid and we can not use the mean of CGD as ARL. This paper concentrate on that point. By adopting one generalized binomial distribution(GBD) model that allows correlated Bernoulli trials, generalized geometric distribution(GGD) is defined and its mean is derived to find an alternative ARL when the process is in out-of-control state and the exceeding probabilities take the second form mentioned in the above. Small-scale simulation is performed to show how an alternative ARL works.

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EWMA control chart for Katz family of distributions (카즈분포족에 대한 지수가중이동평균관리도)

  • Cho, Gyo-Young
    • Journal of the Korean Data and Information Science Society
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    • v.21 no.4
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    • pp.681-688
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    • 2010
  • In statistical process control, the primary method used to monitor the number of nonconformities is the c-chart. The conventional c-chart is based on the assumption that the occurrence of nonconformities in samples is well modeled by a Poisson distribution. When the Poisson assumption is not met, the X-chart is often used as an alternative charting scheme in practice. And EWMA control chart is used when it is desirable to detect out-of-control situations very quickly because of sensitive to a small or gradual drift in the process.

A Linear Filtering Method for Statistical Process Control with Autocorrelated Data (자기상관 데이터의 통계적 공정관리를 위한 선형 필터 기법)

  • Jin Chang-Ho;Apley Daniel W.
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2006.05a
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    • pp.92-100
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    • 2006
  • In many common control charting situations, the statistic to be charted can be viewed as the output of a linear filter applied to the sequence of process measurement data. In recent work that has generalized this concept, the charted statistic is the output of a general linear filter in impulse response form, and the filter is designed by selecting its impulse response coefficients in order to optimize its average run length performance. In this work, we restrict attention to the class of all second-order linear filters applied to the residuals of a time series model of the process data. We present an algorithm for optimizing the design of the second-order filter that is more computationally efficient and robust than the algorithm for optimizing the general linear filter. We demonstrate that the optimal second-order filter performs almost as well as the optimal general linear filter in many situations. Both methods share a number of interesting characteristics and are tuned to detect any distinct features of the process mean shift, as it manifests itself in the residuals.

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A Note on the Robustness of the X Chart to Non-Normality

  • Lee, Sung-Im
    • Communications for Statistical Applications and Methods
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    • v.19 no.5
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    • pp.685-696
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    • 2012
  • These days the interest of quality leads to the necessity of control charts for monitoring the process in various fields of practical applications. The $\overline{X}$ chart is one of the most widely used tools for quality control that also performs well under the normality of quality characteristics. However, quality characteristics tend to have nonnormal properties in real applications. Numerous recent studies have tried to find and explore the performance of $\overline{X}$ chart due to non-normality; however previous studies numerically examined the effects of non-normality and did not provide any theoretical justification. Moreover, numerical studies are restricted to specific type of distributions such as Burr or gamma distribution that are known to be flexible but can hardly replace other general distributions. In this paper, we approximate the false alarm rate(FAR) of the $\overline{X}$ chart using the Edgeworth expansion up to 1/n-order with the fourth cumulant. This allows us to examine the theoretical effects of nonnormality, as measured by the skewness and kurtosis, on $\overline{X}$ chart. In addition, we investigate the effect of skewness and kurtosis on $\overline{X}$ chart in numerical studies. We use a skewed-normal distribution with a skew parameter to comprehensively investigate the effect of skewness.

Low temperature growth of carbon nanotube by plasma enhanced chemical vapor deposition (PECVD) using nickel catalyst

  • Ryu, Kyoung-Min;Kang, Mih-Yun;Kim, Yang-Do;Hyeongtag-Jeon
    • Proceedings of the International Microelectronics And Packaging Society Conference
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    • 2000.04a
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    • pp.109-109
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    • 2000
  • Recently, carbon nanotube has been investigating for field emission display ( (FED) applications due to its high electron emission at relatively low electric field. However, the growing of carbon nanotube generally requires relatively high temperature processing such as arc-discharge (5,000 ~ $20,000^{\circ}C$) and laser evaporation (4,000 ~ $5,000^{\circ}C$) methods. In this presentation, low temperature growing of carbon nanotube by plasma enhanced chemical vapor deposition (PECVD) using nickel catalyst which is compatible to conventional FED processing temperature will be described. Carbon n notubes with average length of 100 run and diameter of 2 ~ $3\mu$ill were successfully grown on silicon substrate with native oxide layer at $550^{\circ}C$using nickel catalyst. The morphology and microstructure of carbon nanotube was highly depended on the processing temperature and nickel layer thickness. No significant carbon nanotube growing was observed with samples deposited on silicon substrates without native oxide layer. This is believed due to the formation of nickel-silicide and this deteriorated the catalytic role of nickel. The formation of nickel-silicide was confirmed by x-ray analysis. The role of native oxide layer and processing parameter dependence on microstructure of low temperature grown carbon nanotube, characterized by SEM, TEM XRD and R없nan spectroscopy, will be presented.

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A binomial CUSUM chart for monitoring type I right-censored Weibull lifetimes (제1형의 우측중도절단된 와이블 수명자료를 관리하는 이항 누적합 관리도)

  • Choi, Min-jae;Lee, Jaeheon
    • The Korean Journal of Applied Statistics
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    • v.29 no.5
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    • pp.823-833
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    • 2016
  • The lifetime is a key characteristic of product quality. It is best to obtain the lifetime data of all samples, but they are often censored due to time or expense limitations. In this paper, we propose a binomial cumulative sum (CUSUM) chart to monitor the mean of type I right-censored Weibull lifetime data, for a xed value of the Weibull shape parameter. We compare the performance of the proposed binomial CUSUM chart with CUSUM charts studied previously using the steady-state average run length (ARL). The results show that the performance of the binomial CUSUM chart is better when the censoring rate is high and/or the sample size is small.