• Title/Summary/Keyword: statistical characteristics

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On the characteristics of statistical expert system and a strategy to choose development tools (통계전문가시스템의 특성과 개발도구의 선택)

  • 허문열
    • The Korean Journal of Applied Statistics
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    • v.4 no.1
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    • pp.85-92
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    • 1991
  • This paper describes the trend and inherent problems of the current statistical packages, and statistical expert system is suggested as an alternative to the conventional statistical packages. The paper then describes the components and characteristics of statistical expert system, and suggests a strategy to choose development tools to build a system.

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Social Network Analysis and Its Applications for Authors and Keywords in the JKSS

  • Kim, Jong-Goen;Choi, Soon-Kuek;Choi, Yong-Seok
    • Communications for Statistical Applications and Methods
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    • v.19 no.4
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    • pp.547-558
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    • 2012
  • Social network analysis is a graphical technique to search the relationships and characteristics of nodes (people, companies, and organizations) and an important node for positioning a visualized social network figure; however, it is difficult to characterize nodes in a social network figure. Therefore, their relationships and characteristics could be presented through an application of correspondence analysis to an affiliation matrix that is a type of similarity matrix between nodes. In this study, we provide the relationships and characteristics around authors and keywords in the JKSS(Journal of the Korean Statistical Society) of the Korean Statistical Society through the use of social network analysis and correspondence analysis.

Contact Modeling between the Ground and the Galloping Quadruped Robot Considering Statistical Characteristics of Coulomb Friction Coefficients (쿨롱 마찰계수들의 통계적 특성을 고려한 지면과 갤러핑을 하는 4 족 로봇간 접촉 모델링)

  • Kwon, Sung-Hun;Park, Jong-Hyeon;Yoo, Hong-Hee
    • Proceedings of the KSME Conference
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    • 2007.05a
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    • pp.826-830
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    • 2007
  • The effects of the statistical properties of the Coulomb friction coefficients on the dynamic responses of a galloping quadruped robot are investigated in this paper. In general, the Coulomb friction coefficients are assumed to be deterministic for a controller design to achieve required motion characteristics. However, the friction coefficients between the ground and the robot legs are not constant in reality. Therefore, statistical characteristics of the friction coefficients need to be considered for a multi-body modeling of the robot galloping on the ground. The effects of the statistical properties on the dynamic responses of the quadruped robots are investigated.

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Statistical Estimation of Modal Characteristics of a Structural System Based on Design Variable Samples (설계변수 표본에 근거한 구조시스템 모달 특성의 통계적 예측)

  • Kim, Yong-Woo;Yoo, Hong-Hee
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.33 no.11
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    • pp.1314-1319
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    • 2009
  • The design methods of mechanical systems are largely classified into deterministic methods and stochastic methods. In deterministic methods, design parameters are assumed to have fixed values. On the other hand, in stochastic methods, design parameters are assumed to be statistically distributed. When a stochastic method is employed, statistical characteristics of the populations of design variables are assumed to be known. However, very often, it is almost impossible or very expensive to obtain the statistical characteristics of the populations. Therefore a sample survey method is usually employed for stochastic methods. This paper describes the procedure of estimating the statistical characteristics of populations by employing sample data sets. An example of AFM micro cantilever beam is employed to show the effectiveness of the procedure.

Effects of Spreadsheet-used Instruction on Statistical Thinking and Attitude (스프래드시트를 활용한 수엽이 통계적 사고 및 태도에 미치는 효과)

  • Lee, Jong-Hak;Kim, Won-Kyoung
    • The Mathematical Education
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    • v.50 no.2
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    • pp.185-212
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    • 2011
  • The purpose of this study is to analyze whether spreadsheet-used instruction can improve statistical thinking ability and attitude and also to identify what characteristics of statistical thinking is constructed. For this study, a subject of 2 classes were randomly selected among the 12 classes of the 11th grader in D high school and designated one class as the experimental group and the other class as the control group. Eight hours of the spread sheet-used instruction and the traditional textbook-oriented instruction had been carried out in each class. The research findings are as follows. First, the spread sheet-used instruction is shown to be more effective in enhancing statistical thinking than the traditional textbook-oriented instruction. Second, the spread sheet-used instruction is shown to be more effective in improving statistical attitude than the traditional textbook-oriented instruction. Third, students have shown the various characteristics of statistical thinking in the data descriptive process, data arrange-summary process, data representing process, and data analying process through the spread sheet-used instructions. Hence, the spread sheet-used instruction is recommended in teaching statistics.

Development of Fuzzy-Statistical Control Chart for Processing Uncertain Process Information (불명확한 공정정보 처리를 위한 퍼지-통계적 관리도의 개발)

  • 김경환;하성도
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.2
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    • pp.75-80
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    • 1998
  • Process information is known to have the continuous distribution in many manufacturing processes. Generalized p-chart has been developed for controlling processes by classifying the information characteristics into several groups. But it is improper to describe continuous processes with the classified process informal ion, which is based on the classical set concept. Fuzzy control chart, has been developed for the control of linguistic data, but it is also based on the dichotomous notion of classical set theory. In this paper, fuzzy sampling method is studied in order to process the uncertain data properly. The method is incorporated with the fuzzy control chart. Statistical characteristics of the fuzzy representative value are utilized to device the fuzzy-statistical control chart. The fuzzy-statistical control chart is compared with the generalized p-chart and both the sensitivity to the process information distribution change pared robustiness against the noise on the process information of the fuzzy-statistical control chart are shown to be superior.

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Comparative Evaluation of Reproducibility for Spatio-temporal Rainfall Distribution Downscaled Using Different Statistical Methods (통계적 공간상세화 기법의 시공간적 강우분포 재현성 비교평가)

  • Jung, Imgook;Hwang, Syewoon;Cho, Jaepil
    • Journal of The Korean Society of Agricultural Engineers
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    • v.65 no.1
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    • pp.1-13
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    • 2023
  • Various techniques for bias correction and statistical downscaling have been developed to overcome the limitations related to the spatial and temporal resolution and error of climate change scenario data required in various applied research fields including agriculture and water resources. In this study, the characteristics of three different statistical dowscaling methods (i.e., SQM, SDQDM, and BCSA) provided by AIMS were summarized, and climate change scenarios produced by applying each method were comparatively evaluated. In order to compare the average rainfall characteristics of the past period, an index representing the average rainfall characteristics was used, and the reproducibility of extreme weather conditions was evaluated through the abnormal climate-related index. The reproducibility comparison of spatial distribution and variability was compared through variogram and pattern identification of spatial distribution using the average value of the index of the past period. For temporal reproducibility comparison, the raw data and each detailing technique were compared using the transition probability. The results of the study are presented by quantitatively evaluating the strengths and weaknesses of each method. Through comparison of statistical techniques, we expect that the strengths and weaknesses of each detailing technique can be represented, and the most appropriate statistical detailing technique can be advised for the relevant research.

An assessment of the effect of hull girder vibration on the statistical characteristics of wave loads

  • Ogawa, Yoshitaka;Takagi, Ken
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.3 no.1
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    • pp.80-85
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    • 2011
  • For the assessment of statistical characteristics of wave loads in the real sea state, the probability distribution of wave loads are computed based on the sufficient duration of computations in irregular waves. First of all, the estimation of wave impact loads is well modified applying the displacement potential formulation, which was proposed by one of authors, for solving Wagner's flow model. Consequently, the present computation method is also modified. Prior to the computation in irregular waves, preliminary computation to determine the adequate number of realization of irregular waves is examined. The effect of hull girder vibration on the statistical characteristics is examined by means of the computation with/without hull girder vibration. It is found that hull girder vibration has a certain effect on the probability of occurrence of wave loads. Furthermore, computations taking account of the effect of operation, that is the effects of ship speed and course change, is conducted for the rational evaluation of the effects of hull girder vibration. It is clarified that the effect of operation on the statistical characteristics of wave loads is significant. It is verified that the evaluation without the effect of operation may overestimate the effect of hull girder vibration.

Reliability Analysis of Reduction Factor for Structural Design Guideline(draft) of Fiber Reinforced High Strength Concrete (섬유보강 고강도 콘크리트 구조설계지침(안)의 저감계수에 대한 신뢰도 분석)

  • Kim, Ah-Ryang;Choi, Jungwook;Paik, Inyeol
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.9 no.1
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    • pp.100-108
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    • 2021
  • The purpose of this study is to analyze the reliability index of a design by applying the reduction factor of the recently developed fiber reinforced high strength concrete design guideline(draft). By collecting material and member test data performed for the development of the design guideline(draft), statistical characteristics of material strength and member strength analysis equations are obtained. A simul ation that appl ies the material statistical characteristics and the member anal ysis equation of the design guidel ine(draft) is performed, and the statistical characteristics of the section strength are calculated by combining the statistical characteristics of the analysis equation. Reliability analysis was performed by applying the load combination of the domestic highway bridge design code and concrete structural code, and it was confirmed that the design that applies the reduction factor for materials and members suggested in the design guideline(draft) satisfies the target reliability index.

Recent Developments in Discriminant Analysis fro man Information Geometric Point of View

  • Eguchi, Shinto;Copas, John B.
    • Journal of the Korean Statistical Society
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    • v.30 no.2
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    • pp.247-263
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    • 2001
  • This paper concerns a problem of classification based on training dta. A framework of information geometry is given to elucidate the characteristics of discriminant functions including logistic discrimination and AdaBoost. We discuss a class of loss functions from a unified viewpoint.

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