• Title/Summary/Keyword: Size-control

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Economic Design of Variable Sample Size ${\bar{X}}$ Control Chart Using a Surrogate Variable (대용변수를 이용한 가변형 부분군 크기 ${\bar{X}}$ 관리도의 경제적 설계)

  • Lee, Tae Hoon;Lee, Min Koo;Kwon, Hyuck Moo;Hong, Sung Hoon;Lee, Jooho
    • Journal of Korean Society for Quality Management
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    • v.45 no.4
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    • pp.943-956
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    • 2017
  • Purpose: This paper proposes a VSS(Variable Sample Size) ${\bar{X}}$ control chart using surrogate variable and shows its effectiveness compared with FSS(Fixed Sample Size) ${\bar{X}}$ control chart using either performance variable or surrogate variable. Methods: The expected cost function of VSS ${\bar{X}}$ control chart is derived. The optimal designs are then found for numerical examples using a GA(genetic algorithm) and compared to those of the FSS ${\bar{X}}$ control charts. Results: Computational results show that VSS ${\bar{X}}$ control chart using surrogate variables is superior to FSS ${\bar{X}}$ control chart using either performance variable or surrogate variable from the economic view points. Conclusion: The proposed VSS ${\bar{X}}$ control chart will be useful in industry fields where a performance variable is not avaliable or too costly.

The Proposal of a Size-Spec. for Adult Women (성인 여성의 정면 체형별 사이즈 스팩의 제안)

  • 최유경;이순원
    • Journal of the Korean Society of Clothing and Textiles
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    • v.23 no.4
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    • pp.575-583
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    • 1999
  • Abstract The purpose of this study was to propose a new size-spec. which was applied to four frontal bodytype -X, Y, A and H type-of adult women. Control dimensions of the upper garments were stature bust girth and hip girth. And those of lower garments were waist girth and hip girth. To establish the interval of the control dimensions means and standard deviations were used. By distributing the data of 486 subjects a new size-spec. was proposed. According to the new size-spec. in case of upper garments about 45.7% of subjects were covered by 37 size-speces. and lower garments about 85.9% were covered by 36 The strong point of new size-spec. is to consider the formal feature of each bodytypes. So by trying to apply the new size-spec. to rady-made garments comfort and fitness of those are satisfied.

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MPPT Control of Photovoltaic using Variable IC Method (가변 IC 방법을 이용한 태양광 발전의 MPPT 제어)

  • Ko, Jae-Sub;Chung, Dong-Hwa
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.26 no.8
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    • pp.27-34
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    • 2012
  • This paper proposes variable incremental conductance(IC) algorithm for maximum power point tracking(MPPT) control of photovoltaic. The conventional perturbation & observation(PO) and IC MPPT control algorithm generally uses fixed step size. A small step size reduces a tracking error in the steady state but slows a tracking speed in the transient state. Also, a large step size is fast a tracking speed but increases a tracking error. Therefore, this paper proposes variable IC MPPT algorithm that adjust automatically step size according to operating conditions. To improve a tracking speed and accuracy, when operating point is far from the maximum power point(MPP), the step size uses maximum value and when a operating point is near from the MPP, the step size uses variable step size that adjust according to slope of P-V curve. The validity of MPPT algorithm proposed in this paper prove through compare with conventional PO and IC MPPT algorithm.

Grain Size Determination of Copper Film by Electron Backscatter Diffraction (EBSD를 이용한 구리박막의 결정립 크기 결정)

  • Kim, Su-Hyeon;Kang, Joo-Hee;Han, Seung Zeon
    • Korean Journal of Metals and Materials
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    • v.48 no.9
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    • pp.847-855
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    • 2010
  • The grain size of a cross-section of $8{\mu}m$-thick copper film was determined by electron backscatter diffraction analysis. Grain size distribution histogram showed the presence of a large fraction of small-sized grains, and the mean grain size was significantly affected by handling of them. A cut-off grain size, below which all grains are ignored as noise and eliminated for the calculation of the mean value, should be three or four times as large as the step size. Due to the presence of small grains, the linear intercept method derived larger mean grain size, which depends less sensitively on the cut-off grain size than the equivalent circle diameter method.

The Effect of Kinesio Taping on Pain, Muscle Strength and Balance Control Ability by Age Group: A Literature Review

  • Lee, So-Jeong;Lee, Dongyeop;Hong, Ji-Heon;Yu, Jae-Ho;Kim, Jin-Seop;Kim, Seong-gil
    • The Journal of Korean Physical Therapy
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    • v.33 no.3
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    • pp.142-147
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    • 2021
  • Purpose: The purpose of this study is to objectively and systematically investigate the effect of Kinesio taping by organizing and analyzing the research results using effect size. Methods: A total of 1,000 papers was searched, and 100 of them were selected the first time. Afterward, the effects of taping were analyzed and classified papers that studied balance, muscle strength, and pain, and finally 34 papers were selected. The effect size was calculated using the Effect Size Calculators (University of Colorado, USA) program. Statistical analysis was performed by using PASW Statistics software version 23.0 (IBM Co., Armonk, NY, USA). Descriptive statistics were used to obtain the effect size and confidence interval for each group. Results: In a study related to balance control ability, the effect size was 1.519 in the young subjects group (20-39 years old), and the effect size in the elderly group (65 years or older) was 0.360. In a study related to muscle strength, the effect size was 0.469 in the group of young subjects and 0.250 in the middle-aged group (40-65 years old), and the effect size of the elderly group was 0.848. In the study related to pain control, the effect size was 0.469 in the young group, the effect size of the middle-aged group was 0.972, and the effect size of the elderly group was 1.040. Conclusion: Kinesio taping differed in the degree of effect according to the age group of the subjects, but it was effective in balance control ability, muscle strength, and pain.

A VSR $\bar{X}$ Chart with Multi-state VSS and 2-state VSI Scheme

  • Lee, Jae-Heon;Park, Chang-Soon
    • Journal of Korean Society for Quality Management
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    • v.32 no.4
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    • pp.252-264
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    • 2004
  • Variable sampling Interval (VSI) control charts vary the sampling interval according to value of the control statistic while the sample size is fixed. It is known that control charts with 2-state VSI scheme, which uses only two sampling intervals, give good statistical properties. Variable sample size (VSS) control charts vary the sample size according to value of the control statistic while the sampling interval is fixed. In the VSS scheme no optimal results are known for the number of sample sizes. It is also known that the variable sampling rate (VSR) $\bar{X}$ control chart with 2-state VSS and 2-state VSI scheme leads to large improvements In performance over the fixed sampling rate (FSR) $\bar{X}$ chart, but the optimal number of states for sample size Is not known. In this paper, the VSR Χ charts with multi-state VSS and 2-state VSI scheme are designed and compared to 2-state VSS and 2-state VSI scheme. The multi-state VSS scheme is considered to, achieve an additional improvement by switching from the 2-state VSS scheme. On the other hand, the multi-state VSI scheme is not considered because the 2-state scheme is known to be optimal. The 3-state VSS scheme improves substantially the sensitivity of the $\bar{X}$ chart especially for small and moderate mean shifts.

Control system with neural networks for product crystal size of sodium chloride

  • Shinto, Toshiharu;Ishimaru, Naoyuki
    • 제어로봇시스템학회:학술대회논문집
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    • 1994.10a
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    • pp.725-730
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    • 1994
  • A sodium chloride crystallizer shows oscillatory and nonlinear characteristics under its nucleating and growing process. Because these characteristics vary with operational condition, we can't control the product crystal size exactly with a PID controller or a sequence controller. Then, we make a model with threefold neural networks for the laboratory equipment that is a jet mixing crystallizer. We try to control the product crystal size with its neuro-model, and we reach the conclusion that our neuro-model is applicable to the practical crystallizer.

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Unstructured Quadrilateral Surface Grid Generation and Cell Size Control

  • Kim, Byoung-Soo
    • 한국전산유체공학회:학술대회논문집
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    • 2008.03a
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    • pp.386-389
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    • 2008
  • In this paper grid generation of unstructured quadrilateral surface grids is described. The current approach uses conventional Advancing Front Method which is used to generate unstructured triangular grids. Grid cell size control is done by using closeness-based global interpolation method controlled by pre-described control elements. Algorithm and procedure for quadrilateral grid generation using AFM method and cell size control method are described. Examples of quadrilateral grid generation are shown, and difficulties and problems related to the current approach are also discussed.

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Unstructured Quadrilateral Surface Grid Generation and Cell Size Control

  • Kim, Byoung-Soo
    • 한국전산유체공학회:학술대회논문집
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    • 2008.10a
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    • pp.386-389
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    • 2008
  • In this paper grid generation of unstructured quadrilateral surface grids is described. The current approach uses conventional Advancing Front Method which is used to generate unstructured triangular grids. Grid cell size control is done by using closeness-based global interpolation method controlled by pre-described control elements. Algorithm and procedure for quadrilateral grid generation using AFM method and cell size control method are described. Examples of quadrilateral grid generation are shown, and difficulties and problems related to the current approach are also discussed.

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Sample Size and Power Estimation in Case-Control Genetic Association Studies

  • Ahn Chul
    • Genomics & Informatics
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    • v.4 no.2
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    • pp.51-56
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    • 2006
  • In planning a genetic association study, it is necessary to determine the number of samples to be collected for the study in order to achieve sufficient power to detect the hypothesized effect. The case-control design is increasingly used for genetic association studies due to the simplicity of its design. We review the methods for the sample size and power calculations in case-control genetic association studies between a marker locus and a disease phenotype.