• Title/Summary/Keyword: Deviation index

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A Process Capability Index $C_{pd}$ Consistent with the Proportion of Nonconforming Items (불량률과 이치하는 공정능력 지수 $C_{pd}$)

  • Im, Tae-Jin;Pyun, Si-Sub
    • Journal of Korean Society for Quality Management
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    • v.28 no.2
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    • pp.103-122
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    • 2000
  • Process capability indices (PCI) $C_p\;C_{pk},\;C_m,\;and\;C_{pmk}$ are widely used to evaluate the process performance. The PCI's have been evolved to consider the 'off targetness' more adequately. However, all of these indices are found to be inconsistent with the proportion of nonconforming items, in some cases. That is, the PCI for a process may result in higher value even when the proportion of defectives increases. For these reasons, we propose a new capability index, $c_{pd}$, which is consistent with the defect rate. The characteristics of the new PCI, $c_{pd}$ are investigated with respect to the existing PCI's. Some statistical properties of an estimator for $c_{pd}$ are also investigated by a Monte Carlo simulation. Sensitivity study under minor deviation from normality is also performed to show the robustness of $c_{pd}$. A good estimator for $c_{pd}$ is under study.

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Site Quality Evaluation Prototype for Building Deck-plate Construction

  • Shim, Young-Bo;Cho, Dong-Hyun;Koo, Kyo-Jin
    • Journal of the Korea Institute of Building Construction
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    • v.13 no.1
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    • pp.90-100
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    • 2013
  • Deck-plates are widely used on construction sites, and have the advantage of enabling contractors to achieve a relatively uniform quality. But nevertheless, quality deviation in deck-plate construction can occur as the result of differences in site conditions and the experience of crew workers. In this study, the authors present a site quality evaluation prototype for building deck-plate construction. Through analyses of case studies and interviews with experts, standard quality check sheets and a quality management index were developed by estimating the importance of quality check items based on a Failure Mode and Effects Analysis (FMEA) method. The applicability and effectiveness of the prototype was evaluated through a case study and interviews with case participants. It was found that the prototype promoted an active quality management as a way of continuously improving quality management in deck-plate construction instead of passive quality inspection practice.

A Study on the Feasibility Analysis for the Use of Solar Energy in Korea Using a Satellite (인공위성을 이용한 한반도에서의 태양에너지 이용가능성 분석에 관한 연구)

  • Jo, D.K.;Kang, Y.H.;Auh, C.M.
    • Journal of the Korean Solar Energy Society
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    • v.22 no.3
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    • pp.21-30
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    • 2002
  • Images taken by geostationary satellite may be used to estimate solar irradiance fluxes at earth's surface. It is based on the empirical correlation between a satellite derived cloud index and the irradiance at the ground. For the validation. estimated solar radiation fluxes are compared with observed solar radiation fluxes at 16 sites over the Korean peninsular from January 1982 to December 2000. Estimated solar radiation fluxes show reliable results for estimating the global radiation with average deviation of -5.6 to +2.8% from the measured values and the yearly averaged horizontal global insolation of Korean peninsula was turned out to be $3.038kcal/m^2.day$.

Revaluation of Solar Radiation Resources in Korean Peninsular (한반도 태양에너지 자원의 재평가)

  • Jo, Dok-Ki;Yun, Chang-Yeol;Kim, Kwang-Deuk;Kang, Young-Heack
    • 한국태양에너지학회:학술대회논문집
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    • 2009.11a
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    • pp.50-55
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    • 2009
  • Images taken by geostationary satellite may be used to estimate solar irradiance fluxes at earth's surface. It is based on the empirical correlation between a satellite derived cloud index and the irradiance at the ground. For the validation, estimated solar radiation fluxes are compared with observed solar radiation fluxes at 16 sites over the Korean peninsular from January 1982 to December 2007. Estimated solar radiation fluxes show reliable results for estimating the global radiation with average deviation of -7.58 to +3.8% from the measured values and the yearly averaged horizontal global insolation of Korean peninsula was turned out to be $3.59kW/m^2/day$.

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The Improvement and Completion of Outcome index: A new assessment system for quality of orthodontic treatment

  • Hong, Mihee;Kook, Yoon-Ah;Kim, Myeng-Ki;Lee, Jae-Il;Kim, Hong-Gee;Baek, Seung-Hak
    • The korean journal of orthodontics
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    • v.46 no.4
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    • pp.199-211
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    • 2016
  • Objective: Given the considerable disagreement between the Peer Assessment Rating (PAR) index and the American Board of Orthodontics Cast-Radiograph Evaluation, we aimed to develop a novel assessment system-the Improvement and Completion of Outcome (ICO) index-to evaluate the outcome of orthodontic treatment. Methods: Sixteen criteria from 4 major categories were established to represent the pretreatment malocclusion status, as well as the degree of improvement and level of completion of outcome during/after treatment: dental relationship (arch length discrepancy, irregularity, U1-SN, and IMPA); anteroposterior relationship (overjet, right and left molar position, ANB); vertical relationship (anterior overbite, anterior open-bite, lateral open-bite, SN-MP); and transverse relationship (dental midline discrepancy, chin point deviation, posterior cross-bite, occlusal plane cant). The score for each criterion was defined from 0 or -1 (worst) to 5 (ideal value or normal occlusion) in gradations of 1. The sum of the scores in each category indicates the area and extent of the problems. Improvement and completion percentages were estimated based on the pre- and post-treatment total scores and the maximum total score. If the completion percentage exceeded 80%, treatment outcome was considered successful. Results: Two cases, Class I malocclusion and skeletal Class III malocclusion, are presented to represent the assessment procedure using the ICO index. The difference in the level of improvement and completion of treatment outcome can be clearly explained by using 2 percentage values. Conclusions: Thus, the ICO index enables the evaluation of the quality of orthodontic treatment objectively and consecutively throughout the entire treatment process.

Measurement of the Refractive Index of a Mixed Polymer by a Prism Spectrometer and its Application (프리즘 분광계를 이용한 혼합 폴리머의 굴절률 측정과 응용)

  • Kim, Ji-Young;Ju, Young-Gu
    • Korean Journal of Optics and Photonics
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    • v.28 no.5
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    • pp.221-228
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    • 2017
  • We measured the refractive index of a mixed polymer (NOA61, NOA84) in the liquid and solid states. First we made a hollow prism and filled it with UV (ultraviolet) epoxy. Measurement of the apex angle and the minimum-deviation angle gave the refractive index of the liquid polymer. To measure the refractive index of the solid polymer, an additional structure was included in the hollow prism, and the UV epoxy filling in the hollow prism was hardened. In both cases of liquid and solid polymers, the refractive index of the mixed polymer turned out to be proportional to the mix ratio. These results provide a method to vary the focal length of a double stacked cylindrical microlens array using UV epoxy.

A Study on Establishment of the Optimal Target Exposure Index for Skull Radiography Based on Diagnostic Reference Level (진단참고수준 기반 두부 방사선검사의 최적 목표노출지수 설정에 관한 연구)

  • Park, Hye-Min;Yoon, Yong-Su;Kim, Eun-Hye;Jeong, Hoi-Woun;Kim, Jung-Su
    • Journal of radiological science and technology
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    • v.44 no.6
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    • pp.599-605
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    • 2021
  • The International Electrotechnical Commission (IEC) 62494-1 has defined the exposure index (EI) that have a proportional relationship with the dose incident on the image receptor, and target exposure index (EIT), deviation index (DI). In this study, an appropriate EIT for skull radiography was established through the diagnostic reference level (DRL) and changes in DI were confirmed. Entrance surface dose (ESD) and EI were obtained using the computed radiography system displayed the EI as per IEC on console and skull phantom by experiment based on the national average exposure conditions announced in 2012 and 2019. And appropriate EIT was established by applying the DRL in 2012 and 2019. As a results, the EIT is changed according to the change in the DRL, and the exposure condition that becomes the ideal DI according to the change in the EIT also has a difference of about 1.41 times. DRL is recommended to optimize the patient dose, however it is difficult to measure in real time at medical institutions whereas EI and DI are displayed on the console at the same time as exposure. When the EIT is set based on the DRL and the DI is closed to an ideal value, it is useful as a patient dose management tool. Therefore, when the EIT is periodically managed along with the revision of the DRLs, the patient dose can be optimized through the EI, EIT and DI.

A Study of Family Adaptation with Chronically III Patients (I) - Stroke Patients at an Oriental Medical Hospital - (만성질환자 가족의 질병 적응과정 연구(I) - 한방병원에 입원한 뇌졸중 환자를 중심으로 -)

  • Lee, Young-Ae
    • Journal of East-West Nursing Research
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    • v.3 no.1
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    • pp.96-103
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    • 1998
  • This study was conducted to identify the adaptation process of the families with chronically ill patients. A descriptive comparative research design was used to the subjects of forty families that have stroke patients at an oriental medical hospital. Research tools were Demands of Illness Inventory(Woods, Haberman & Packard, 1987), Relative and Friend Support Index(McCubbin, Patterson & Glynn, 1982), Family Coping-Coherence Index (McCubbin, Larsen & Olson, 1982), Family Hardiness Index(McCubbin, McCubbin & Thompson, 1986), and Family Member Wellbeing Scale(McCubbin, McCubbin & Thompson, 1986). Data were collected from October 7, 1998 to November 7, 1998 at an oriental medical hospital located in IkSan city. The number of cases was forty and the data were analyzed by SPSS $PC^+$. Descriptive statistics of frequency, number, mean and standard deviation were used to report the results. The results were as follows ; 1. There was no significant differences between the two groups on the family stress. 2. There was significant differences between the two groups on the family strength (t value = - 3.09, p value=$.004^{**}$). 3. There was significant differences between the two groups on the family adaptation(t value= -2.08, pvalue=$.05^*$).

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Mid-upper-arm circumference as a screening measure for identifying children with elevated body mass index: a study for Pakistan

  • Asif, Muhammad;Aslam, Muhammad;Altaf, Saima
    • Clinical and Experimental Pediatrics
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    • v.61 no.1
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    • pp.6-11
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    • 2018
  • Purpose: Mid-upper-arm circumference (MUAC) is considered an alternative screening method for obesity. The aims of this investigation were to examine the ability of MUAC to correctly identify children with elevated body mass index (BMI) and to determine the best MUAC cutoff point for identification of children with high BMI. Methods: Anthropometric measurements (height, weight, and MUAC) from a cross-sectional sample of 7,921 Pakistani children aged 5-14 years were analyzed. Pearson correlation coefficients between MUAC and other anthropometric measurements were calculated. Receiver operating characteristic curve analysis was used to determine the optimal MUAC cutoff point for identifying children with high BMI. Results: Among 7,921 children, the mean (${\pm}$standard deviation) age, BMI, and MUAC were 10.00 (${\pm}2.86years$), 16.16 (${\pm}2.66kg/m^2$), and 17.73 (${\pm}2.59cm$), respectively. The MUAC had a strong positive correlation with BMI. The optimal MUAC cutoff points indicating elevated BMI in boys ranged from 16.76 to 22.73, while the corresponding values in girls ranged from 16.38 to 20.57. Conclusion: MUAC may be used as a simple indicator of overweight/obesity in children, with reasonable accuracy in clinical settings.

Analysis of Spring Drought Using NOAA/AVHRR NDVI for North Korea (NOAA/AVHRR NDVI를 이용한 북한지역 봄 가뭄 분석)

  • Jang, Min-Won;Yoo, Seung-Hwan;Choi, Jin-Yong
    • Journal of The Korean Society of Agricultural Engineers
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    • v.49 no.6
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    • pp.21-33
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    • 2007
  • Different vegetation indices from satellite images have been used for monitoring drought damages, and this study aimed to develop a drought index using NOAA/AVHRR NDVI(Normalized Difference Vegetation Index) and to analyze the temporal and spatial distribution of spring drought severity in North Korea from 1998 to 2001. A new drought index, DevNDVI(Deviation of NDVI), was defined as the difference between a monthly NDVI and average monthly NDVI at the same cover area, and the DevNDVI images at all years except for 2001 demonstrated the drought-damaged areas referred from various domestic and foreign publications. The vegetation of 2001 showed high vitality despite the least amount of rainfall among the target years, and the reason was investigated that higher temperature above normal average would shift the growing stages of plants ahead. Therefore, complementary methods like plant growth models or ground survey data should be adopted in order to evaluate drought-induced plant stress using satellite-based NDVI and to make up far the distortion induced by other environments than lack of precipitation.