• Title/Summary/Keyword: Statistical assessment

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The Study of Land Aptitude Assessment System Improvement Plan (토지적성평가 체계의 개선방안 연구)

  • Jeong, Jong-Chul;Lee, Sanggil
    • Journal of Environmental Impact Assessment
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    • v.14 no.2
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    • pp.75-81
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    • 2005
  • The purpose of this study is to understand the appropriateness of land aptitude assessment system and to draw up the improvement of this method. The land aptitude assessment system is used to evaluate the effective demand of land development and land conservation. But, this assessment system has the technical problem of selection standards because the land development and the land conservation are against each other. In terms of the relation between development and conservation of land aptitude assessment system, development was increased rapidly as the economic pressure of local government. The application of the land aptitude assessment system using GIS methods was very useful for local plan. However, this system need to improve the selection standards of GIS parameters and statistical methods for the desirable land assessment system.

Reliability Expression for Complex System

  • Seong Cheol Lee
    • Communications for Statistical Applications and Methods
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    • v.3 no.3
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    • pp.125-133
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    • 1996
  • In this paper, we present a algebraic technique for computing system reliability for complex system. The method was originally developed as an aid to fault tree analysis but it applies to general problems of reliability assessment. A success expression which directly gives the reliability expression is formed and simplified by the procedure. Several algorithms and examples are illustrated.

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Assessment for Efficiency of Two-Stage Randomized Response Technique

  • Park, Kyung-Ho
    • Communications for Statistical Applications and Methods
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    • v.7 no.2
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    • pp.427-433
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    • 2000
  • In this paper, we review several two-stage randomized response techniques for gathering self-report data when persons are asked sensitive question. Also efficiencies and privacy protections based on the two-stage randomized response procedures are compared. Finally, we find optimal parameter conditions.

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Some Asymptotic Properties of Conditional Covariance in the Item Response Theory

  • Kim, Hae-Rim
    • Communications for Statistical Applications and Methods
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    • v.7 no.3
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    • pp.959-966
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    • 2000
  • A dimensionality assessment procedure DETECT uses the property of being near zero of conditional covariances as an indication of unidimensionality .This study provides the convergent properties to zero of conditional covariances when the dta is unidimensional, with which DETECT extends its theoretical grounds.

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Accurate Camera Self-Calibration based on Image Quality Assessment

  • Fayyaz, Rabia;Rhee, Eun Joo
    • Journal of Information Technology Applications and Management
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    • v.25 no.2
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    • pp.41-52
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    • 2018
  • This paper presents a method for accurate camera self-calibration based on SIFT Feature Detection and image quality assessment. We performed image quality assessment to select high quality images for the camera self-calibration process. We defined high quality images as those that contain little or no blur, and have maximum contrast among images captured within a short period. The image quality assessment includes blur detection and contrast assessment. Blur detection is based on the statistical analysis of energy and standard deviation of high frequency components of the images using Discrete Cosine Transform. Contrast assessment is based on contrast measurement and selection of the high contrast images among some images captured in a short period. Experimental results show little or no distortion in the perspective view of the images. Thus, the suggested method achieves camera self-calibration accuracy of approximately 93%.

Statistical Effective Interval Determination and Reliability Assessment of Input Variables Under Aleatory Uncertainties (물리적 불확실성을 내재한 입력변수의 확률 통계 기반 유효 범위 결정 방법 및 신뢰성 평가)

  • Joo, Minho;Doh, Jaehyeok;Choi, Sukyo;Lee, Jongsoo
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.41 no.11
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    • pp.1099-1108
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    • 2017
  • Data points obtained by conducting repetitive experiments under identical environmental conditions are, theoretically, required to correspond. However, experimental data often display variations due to generated errors or noise resulting from various factors and inherent uncertainties. In this study, an algorithm aiming to determine valid bounds of input variables, representing uncertainties, was developed using probabilistic and statistical methods. Furthermore, a reliability assessment was performed to verify and validate applications of this algorithm using bolt-fastening friction coefficient data in a sample application.

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.

Logical Consistency in Risk Assessment using the Korean Fuzzy Linguistic Variables (한국어 퍼지 언어변수를 이용한 리스크 평가의 논리적 일관성)

  • Lim, Hyeon-Kyo;Byun, Sanghun
    • Journal of the Korean Society of Safety
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    • v.31 no.4
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    • pp.120-125
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    • 2016
  • Usually, a risk can be expressed as a product of likelihood and consequence of a hazard factor. Therefore, conventional risk assessment is carried out by frequency analysis and severity analysis, in turns. However, it is well known that intuitive thinking is another excellent way of thinking of human beings. This study aimed to confirm whether there exist any difference in risk assessment results derived by two different procedures - intuitive and analytical. Thus, the present study showed 10 different illustrations to 30 undergraduate students. Their responses were organized as fuzzy membership functions, and summarized as risk assessments, and compared. The results were also verified with the help of statistical hypothesis testing, which showed no significant difference. On the contrary, however, similarity measure used in fuzzy set theory was not credible as anticipated. Many cases failed to satisfy statistical hypothesis even with similarity measure higher than 0.60 so that only a trend could be accepted. In addition, a subject showed a somewhat consistent logical discrepancy in his response, which implied the necessity of sincere analysis in fuzzy formulations.

Assessment and Interpretation of Bioequivalence for Two Drug Formulations using Crossover Design

  • Ko, Seoung-gon;Oh, Hyun-Sook
    • Communications for Statistical Applications and Methods
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    • v.6 no.2
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    • pp.601-610
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    • 1999
  • Crossover design is officially except for special occasions recommended by KFDA and FDA for assessing Bioequivalence between two drugs one for reference and the other for innovator. Such design is regarded as a special case of latin square split-polt or repeated measurement design and its main difference with other designing methods is that each subject in an experiment is exposed two drugs in sequence. Therefore general statistical analysis is not suitable since the model for this experiment includes carryover effect in addition to period and sequence effect. in this paper analysis for crossover model with two drugs and its interpretation are mainly discussed and an example is given for illustration.

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Overview of frequent pattern mining

  • Jurg Ott;Taesung Park
    • Genomics & Informatics
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    • v.20 no.4
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    • pp.39.1-39.9
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    • 2022
  • Various methods of frequent pattern mining have been applied to genetic problems, specifically, to the combined association of two genotypes (a genotype pattern, or diplotype) at different DNA variants with disease. These methods have the ability to come up with a selection of genotype patterns that are more common in affected than unaffected individuals, and the assessment of statistical significance for these selected patterns poses some unique problems, which are briefly outlined here.