• Title/Summary/Keyword: Statistical control techniques

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A Review of Statistical Analysis Methods Applied on Traditional Korean Medicine Research (한의학 연구에 활용된 통계분석 방법에 대한 고찰)

  • Jang, Seon-Il;Yun, Young-Gab;Choi, Kyoung-Ho
    • Herbal Formula Science
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    • v.17 no.1
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    • pp.75-83
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    • 2009
  • Objective : The purpose of this study is to indicate of problems in statistical analysis method of "The Korean Journal of oriental Medical Prescription" and we will be proposed the useful application of the statistical analysis method. Methods : In this paper, we were analysed statistical analysis methodology from published journal articles "The Korean Journal of Oriental Medical Prescription" December, year 2000 to December, year 2008. We were investigated of problems in application of structured analysis methods those journal articles that including statistical analysis techniques and analysis methods. Results : 1. A random allocation of the experimental group and control groups are important factors in the planning process of statistical analysis. However, there are less explanation those journal articles. 2. There are no consideration in specimen size that there will be considerate by the level of significance and statistical test. 3. Many article authors were confused between parametric methods and non-parametric methods that they were applied parametric statistical analysis methods although inapplicable sample size. 4. There were applied the parametric methods consists of t-test instead non-parametric methods in the comparison of average intergroup relations. 5. There were less understanding posterior analysis and were confused with t-test. Conclusion : Our goal was to outline the key methods with a brief discussion of problems(statistical analysis methods), avenues for solutions. we recommend authors to use an appropriate statistical analysis methods for obtaining a more cautions results.

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Price Determinant Factors of Artworks and Prediction Model Based on Machine Learning (작품 가격 추정을 위한 기계 학습 기법의 응용 및 가격 결정 요인 분석)

  • Jang, Dongryul;Park, Minjae
    • Journal of Korean Society for Quality Management
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    • v.47 no.4
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    • pp.687-700
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    • 2019
  • Purpose: The purpose of this study is to investigate the interaction effects between price determinants of artworks. We expand the methodology in art market by applying machine learning techniques to estimate the price of artworks and compare linear regression and machine learning in terms of prediction accuracy. Methods: Moderated regression analysis was performed to verify the interaction effects of artistic characteristics on price. The moderating effects were studied by confirming the significance level of the interaction terms of the derived regression equation. In order to derive price estimation model, we use multiple linear regression analysis, which is a parametric statistical technique, and k-nearest neighbor (kNN) regression, which is a nonparametric statistical technique in machine learning methods. Results: Mostly, the influences of the price determinants of art are different according to the auction types and the artist 's reputation. However, the auction type did not control the influence of the genre of the work on the price. As a result of the analysis, the kNN regression was superior to the linear regression analysis based on the prediction accuracy. Conclusion: It provides a theoretical basis for the complexity that exists between pricing determinant factors of artworks. In addition, the nonparametric models and machine learning techniques as well as existing parameter models are implemented to estimate the artworks' price.

Development of the Expert Seasonal Prediction System: an Application for the Seasonal Outlook in Korea

  • Kim, WonMoo;Yeo, Sae-Rim;Kim, Yoojin
    • Asia-Pacific Journal of Atmospheric Sciences
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    • v.54 no.4
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    • pp.563-573
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    • 2018
  • An Expert Seasonal Prediction System for operational Seasonal Outlook (ESPreSSO) is developed based on the APEC Climate Center (APCC) Multi-Model Ensemble (MME) dynamical prediction and expert-guided statistical downscaling techniques. Dynamical models have improved to provide meaningful seasonal prediction, and their prediction skills are further improved by various ensemble and downscaling techniques. However, experienced scientists and forecasters make subjective correction for the operational seasonal outlook due to limited prediction skills and biases of dynamical models. Here, a hybrid seasonal prediction system that grafts experts' knowledge and understanding onto dynamical MME prediction is developed to guide operational seasonal outlook in Korea. The basis dynamical prediction is based on the APCC MME, which are statistically mapped onto the station-based observations by experienced experts. Their subjective selection undergoes objective screening and quality control to generate final seasonal outlook products after physical ensemble averaging. The prediction system is constructed based on 23-year training period of 1983-2005, and its performance and stability are assessed for the independent 11-year prediction period of 2006-2016. The results show that the ESPreSSO has reliable and stable prediction skill suitable for operational use.

APC Technique and Fault Detection and Classification System in Semiconductor Manufacturing Process (반도체 공정에서의 APC 기법 및 이상감지 및 분류 시스템)

  • Ha, Dae-Geun;Koo, Jun-Mo;Park, Dam-Dae;Han, Chong-Hun
    • Journal of Institute of Control, Robotics and Systems
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    • v.21 no.9
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    • pp.875-880
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    • 2015
  • Traditional semiconductor process control has been performed through statistical process control techniques in a constant process-recipe conditions. However, the complexity of the interior of the etching apparatus plasma physics, quantitative modeling of process conditions due to the many difficult features constraints apply simple SISO control scheme. The introduction of the Advanced Process Control (APC) as a way to overcome the limits has been using the APC process control methodology run-to-run, wafer-to-wafer, or the yield of the semiconductor manufacturing process to the real-time process control, performance, it is possible to improve production. In addition, it is possible to establish a hierarchical structure of the process control made by the process control unit and associated algorithms and etching apparatus, the process unit, the overall process. In this study, the research focused on the methodology and monitoring improvements in performance needed to consider the process management of future developments in the semiconductor manufacturing process in accordance with the age of the APC analysis in real applications of the semiconductor manufacturing process and process fault diagnosis and control techniques in progress.

An Investigative Study for the Integration of SPC and EPC (SPC와 EPC 통합에 관한 조사 연구)

  • 김종걸;정해운
    • Journal of the Korea Safety Management & Science
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    • v.4 no.3
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    • pp.107-122
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    • 2002
  • There are two approaches to process control. The one is engineering process control(EPC) which is one of the techniques very widely used in the process industry and based on control theory which aims at keeping the process on target using manipulating variable. The other is statistical process control(SPC) whose main purpose is to look for assignable causes(variability) in the process. To design an integrated or combined scheme of SPC and EPC is gaining recognition in the process experiences for hybrid industry. This paper aims to investigate recent study concerned on the integration of SPC and EPC. First, we consider the difference between SPC and EPC in simple terms and review various models of EPC for integration including evaluation of previous study. Finally, we suggest some prospective research area concerned on the integration of SPC and EPC.

Design of an Effective Human Sensibility Ergonomic Interior Design Analysis Tool (효율적인 감성공학적 인테리어 디자인 분석 도구의 설계)

  • Seo, Hyung-Soo
    • Korean Institute of Interior Design Journal
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    • v.16 no.2 s.61
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    • pp.314-321
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    • 2007
  • The statistical method of human sensibility ergonomics is widely used for analyzing interior design because it has standard processes and it can help to get quantifiable results. However applying this method demands repeated intense work and great time and effort is required. In this study, a tool applying Web and virtual reality techniques for statistical human sensibility ergonomic interior design analysis is proposed and the key parts of the tool including database and interface are implemented. The database contains the sensibility adjective table and the physical interior design factor table for analyzing the relationship between human sense and physical design factors. Interface of the tool is implemented using Web technologies, so testers can evaluate interior design samples via standard Web browsers. The 3D control which is an important component of the interface is also implemented. Employing the suggested tool can reduce effort and time for evaluating human sense in Interior design field.

A Revised Fractal Technique With Fixed Midpoints For A Specific Terrain Model (고정 중간점을 허용하는 프랙탈 기법에 대한 연구)

  • No, Yong-Deok
    • The Transactions of the Korea Information Processing Society
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    • v.3 no.1
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    • pp.160-166
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    • 1996
  • In 2D and 3D computer graphics, fractal techniques have been applied ter rain models. In general, a specific 3D terrain model such as Cheju or Uleung Island could not beformulated by statistical fractalsowing to the randomeffects. However, by locating the control points on the edges and the surface of a specific terrain such as Cheju Island, a similar shape of the terrain model can be simulated. This paper presents the way of formulating a specific 3D terrain model by the statistical fractals with fixed midpoints.

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Development of Extended Process Capability Index in Terms of Error Classification in the Production, Measurement and Calibration Processes (생산, 측정 및 교정 프로세스에서 오차 유형화에 의한 확장 공정능력지수의 개발)

  • Choi, Sung-Woon
    • Journal of the Korea Safety Management & Science
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    • v.11 no.2
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    • pp.117-126
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    • 2009
  • We develop methods for propagating and analyzing EPCI(Extended Process Capability Index) by using the error type that classifies into accuracy and precision. EPCI developed in this study can be applied to the three combined processes that consist of production, measurement and calibration. Little calibration work discusses while a great deal has been studied about SPC(Statistical Process Contol) and MSA(Measurement System Analysis). EPCI can be decomposed into three indexes such as PPCI(Production Process Capability Index), PPPI(Production Process Performance Index), MPCI(Measurement PCD, and CPCI(Calibration PCI). These indexs based on the type of error classification can be used with various statistical techniques and principles such as SPC control charts, ANOVA(Analysis of Variance), MSA Gage R&R, Additivity-of-Variance, and RSSM(Root Sum of Square Method). As the method proposed is simple, any engineer in charge of SPC. MSA and calibration can use efficientily in industries. Numerical examples are presentsed. We recommed that the indexes can be used in conjunction with evaluation criteria.

Monitoring social networks based on transformation into categorical data

  • Lee, Joo Weon;Lee, Jaeheon
    • Communications for Statistical Applications and Methods
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    • v.29 no.4
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    • pp.487-498
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    • 2022
  • Social network analysis (SNA) techniques have recently been developed to monitor and detect abnormal behaviors in social networks. As a useful tool for process monitoring, control charts are also useful for network monitoring. In this paper, the degree and closeness centrality measures, in which each has global and local perspectives, respectively, are applied to an exponentially weighted moving average (EWMA) chart and a multinomial cumulative sum (CUSUM) chart for monitoring undirected weighted networks. In general, EWMA charts monitor only one variable in a single chart, whereas multinomial CUSUM charts can monitor a categorical variable, in which several variables are transformed through classification rules, in a single chart. To monitor both degree centrality and closeness centrality simultaneously, we categorize them based on the average of each measure and then apply to the multinomial CUSUM chart. In this case, the global and local attributes of the network can be monitored simultaneously with a single chart. We also evaluate the performance of the proposed procedure through a simulation study.

Comparison of pain intensity of anterior middle superior alveolar injection with infiltration anesthetic technique in maxillary periodontal surge

  • Shirmohammadi, Adileh;Faramarzi, Masoumeh;Lafzi, Ardeshir;Kashefimehr, Atabak;Malek, Sepideh
    • Journal of Periodontal and Implant Science
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    • v.42 no.2
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    • pp.45-49
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    • 2012
  • Purpose: The aim of the present clinical trial was to compare pain during injection of anterior middle superior alveolar (AMSA) technique with that of infiltration injection technique in the maxilla in periodontal flap surgeries of patients referring to the Department of Periodontics, Faculty of Dentistry, Tabriz University of Medical Sciences. Methods: Twenty subjects with an age range of 20 to 40 years were selected for the present study. One side of the maxilla was randomly selected as the test side and the other as the control side using a flip of a coin. AMSA technique was used on the test side and infiltration technique was used on the control side for anesthesia. On both sides 2% lidocaine containing 1:80,000 epinephrine was used for anesthesia. The operator obtained the visual analogue scale for each patient immediately after the injection and immediately after surgery. Data was analyzed using descriptive statistical methods (frequency percentages, means and standard deviations) and Wilcoxon's test using SPSS ver. 13 (SPSS Inc.). Statistical significance was defined at P<0.05. Results: There were no statistically significant differences in pain during injection between the two techniques (P=0.856). There were statistically significant differences in postoperative pain between the two injection techniques (P=0.024). Conclusions: Postoperative pain in AMSA injection technique was less than that in the infiltration technique. Therefore, the AMSA technique is preferable in the periodontal surgeries for the anesthesia of palatal tissues given the fact that it has other advantages, too.