• Title/Summary/Keyword: statistical evaluation

Search Result 2,789, Processing Time 0.033 seconds

Statistical Evaluation of the Cleft Lip Nose Deformity Image (구순열 환자 코변형(Cleft Lip Nose Deformity) 영상의 통계적 평가)

  • Kim, Jin-Tae;Nam, Ki-Chang;Hong, Hyun-Ki;Rah, Dong-Kyun;Kim, Deok-Won
    • The Transactions of the Korean Institute of Electrical Engineers D
    • /
    • v.54 no.8
    • /
    • pp.517-520
    • /
    • 2005
  • Cleft lip is a congenital deformity condition with separation of the two sides of the lip and results in nose deformity Evaluation of surgical corrections and outcome assessments in nose deformity resulting from the cleft lip depend mainly on doctor's objective judgment. Development of an objective assessment tool in evaluation of the condition and surgical outcome of cleft lip nose deformity patients will help in advancement and evaluation of surgical techniques of cleft lip. Hence, our study aimed at quantitative assessment of a cleft lip nose deformity condition by comparing following parameters gathered from a photographic image of a cleft lip patient: (1) angle difference between two nostril axis, (2) center of the nostril and distance between two centers, (3) overlapped area of two nostrils and (4) the overlapped area ratio of two nostrils. Assessment results of the nose deformity were determined by statistical analysis of evaluation results from three experienced plastic surgeons. In addition, regression model was developed using correlation relationship and factor analysis of parameters from results of the image analysis

Development and Application of an Evaluation Model for Website Design Problem (웹 사이트 디자인 평가모형 및 적용에 관한 연구)

  • 이국철;이성현
    • Journal of Information Technology Applications and Management
    • /
    • v.10 no.1
    • /
    • pp.91-110
    • /
    • 2003
  • The primary goal of this paper is to develop an evaluation model for Web site design that have substantial effects of the performance of marketing and promotion of goods and services of the company. This paper proposes 3 design aspects such as dosing concepts, usability, and artistic coordination. The model also have tested its applicability to real world examples through an appropriate statistical techniques. Then, the model has been actually applied into 6 typical web sites and their design problems are thoroughly investigated and compared each other. Several web site design guidelines are also proposed for web design practitioners.

  • PDF

A Study on the Statistical Distribution of Rebound Number and Ultrasonic Pulse Velocity in RC and PSC Concrete Structures (RC 및 PSC 콘크리트에서 반발도 및 초음파 속도의 변화에 대한 연구)

  • Sa, Min-Hyung;Yoon, Young-Geun;Lee, In-Bok;Woo, In-Sung;Oh, Tae Keun
    • Journal of the Korean Society of Safety
    • /
    • v.32 no.4
    • /
    • pp.53-58
    • /
    • 2017
  • The rebound hammer test and the measurement of ultrasonic pulse velocity(UPV) have been widely used for the physical properties & condition evaluation of reinforced & prestressed concrete structures for a long time, but the acoustoelastic effects by the prestressing in the prestressed concrete structures on the rebound number and ultrasonic pulse velocity have not been studied clearly. Therefore, this study investigated the data distribution of the rebound numbers and ultrasonic pulse velocities in reinforced and prestressed concrete slabs of $3000{\times}3000mm$ with a thickness of 250 mm. Also, the Kolmogorov-Smirnov goodness-of-fit test was done in order to identify statistical consistency and reliability. The statistical analysis results show that the rebound number and ultrasonic pulse velocities increased about 1.9% and 2.5%, respectively when prestressing was applied. As expected, the UPV shows better statistical reliability and potential for in situ evaluation than the RB because the RB are more sensitive to testing posture, surface condition, temperature and humidity so on. The experimental data in this study can be used for the condition assessment of reinforced and prestressed concrete structures by the rebound number and ultrasonic pulse velocity.

Effective Test and Evaluation Approaches for Reliable Defense Systems Development examined through Domestic Defense Cases (국내 사례로 살펴보는 국방체계 개발의 신뢰성을 높이기 위한 시험평가 방안)

  • Seo, Kyung-Min;Lee, Chan Young;Bang, Kyoung Woon;Lee, Dong Chul;Choi, Woo Young;Kim, Tag Gon
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.53 no.2
    • /
    • pp.127-134
    • /
    • 2016
  • This paper presents practical issues for test and evaluation(T&E) methods to develop defense systems. Our argument is motivated by several domestic defense cases and the cases lead us to discuss two main factors for reliable defense systems development: 1) statistical approaches and 2) technical schemes. Specifically, statistical approaches enable to provide credible interpretations about T&E results in the decision-making process. With practical T&E results of the “Red Shark” torpedo, we performed statistical hypothesis tests and suggest a minimum sample size to accept the hypothesis. Next, technical schemes have more direct effects on improving reliability of developed defense systems and we shortly introduce tools development for systems verification that is required to integrate several sub-systems, e.g., combat, sensor, weapon, and communication systems, within a defense system. We additionally summary some domain cases using modeling and simulation techniques for successful T&E. In closing, we expect that the paper shows empirical investigation and lessons learned with these two practical issues, which provides a guide those who desire to make decisions about reliable defense systems development.

Difference between the Domestic and China Tourist of the Destination Image in Busan (부산방문 한.중 관광객의 정서적 이미지 비교)

  • 이종한
    • Journal of Applied Tourism Food and Beverage Management and Research
    • /
    • v.16 no.2
    • /
    • pp.201-216
    • /
    • 2005
  • This study investigated of the differences of the image between the domestic and china tourist of the visiting in busan metropolitan city and their image evaluation were different according to the nationality. The attribute for the destination image types were measured using 27 items. The factors involved in the destination image were analysis and 7 factors emerged. The result are as follows. First, Between the domestic and china tourist of living appeared to statistical different of the destination image. Second, Between destination image and revisiting preference appeared to statistical difference. Third, Between destination image and revisiting preference appeared to statistical difference according to the nationality. Forth, Between destination image and revisiting preference appeared to statistical partially difference according to the nationality. Finally it is also appeared to the statistical difference on the job. ANOVA, t-test was utilized for the above analysis which revealed that a statistic partially difference exited between domestic and china tourist.

  • PDF

Difference between the Domestic and China Tourist of the Destination Image in Busan (부산방문 한 ${\cdot}$ 중 관광객의 정서적 이미지 비교)

  • Lee, Jong-Han
    • Proceedings of the Korea Hospitality Industry Research Society Conference
    • /
    • 2005.11a
    • /
    • pp.21-33
    • /
    • 2005
  • This study investigated of the differences of the image between the domestic and china tourist of the visiting in busan metropolitan city and their image evaluation were different according to the nationality. The attribute for the destination image types were measured using 27 items. The factors involved in the destination image were analysis and 7 factors emerged. The result are as follows. First, Between the domestic and china tourist of living appeared to statistical different of the destination image. Second, Between destination image and revisiting preference appeared to statistical difference. Third, Between destination image and revisiting preference appeared to statistical difference according to the nationality. Forth, Between destination image and revisiting preference appeared to statistical partially difference according to the nationality. Finally it is also appeared to the statistical difference on the job. ANOVA, t-test was utilized for the above analysis which revealed that a statistic partially difference exited between domestic and china tourist.

  • PDF

Statistical Performance Estimation of a Multibody System Based on Design Variable Samples (설계변수 표본에 근거한 다물체계 성능의 통계적 예측)

  • Choi, Chan-Kyu;Yoo, Hong-Hee
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.33 no.12
    • /
    • pp.1449-1454
    • /
    • 2009
  • The performance variation of a multibody system is affected by a variation of various design variables of the system. And the effects of design variable variations on the performance variation must be considered in design of a multibody system. Accordingly, a variation analysis of a multibody system needs to be conducted in design of a multibody system. For a variation analysis of a performance, population mean and variance which are called statistical parameters of design variables are needed. However, an evaluation of statistical parameters of design variables is impossible in many practical cases. Therefore, an estimation of statistical parameters of the performance based on sample mean and variance which are called statistic of design variables is needed. In this paper, the variation analysis method for a multibody system based on design variable samples was proposed. And, using the proposed method, a variation analysis of the vehicle ride comfort based on sample statistic of design variables was conducted.

Cubic normal distribution and its significance in structural reliability

  • Zhao, Yan-Gang;Lu, Zhao-Hui
    • Structural Engineering and Mechanics
    • /
    • v.28 no.3
    • /
    • pp.263-280
    • /
    • 2008
  • Information on the distribution of the basic random variable is essential for the accurate analysis of structural reliability. The usual method for determining the distributions is to fit a candidate distribution to the histogram of available statistical data of the variable and perform approximate goodness-of-fit tests. Generally, such candidate distribution would have parameters that may be evaluated from the statistical moments of the statistical data. In the present paper, a cubic normal distribution, whose parameters are determined using the first four moments of available sample data, is investigated. A parameter table based on the first four moments, which simplifies parameter estimation, is given. The simplicity, generality, flexibility and advantages of this distribution in statistical data analysis and its significance in structural reliability evaluation are discussed. Numerical examples are presented to demonstrate these advantages.

Statistical Fingerprint Recognition Matching Method with an Optimal Threshold and Confidence Interval

  • Hong, C.S.;Kim, C.H.
    • The Korean Journal of Applied Statistics
    • /
    • v.25 no.6
    • /
    • pp.1027-1036
    • /
    • 2012
  • Among various biometrics recognition systems, statistical fingerprint recognition matching methods are considered using minutiae on fingerprints. We define similarity distance measures based on the coordinate and angle of the minutiae, and suggest a fingerprint recognition model following statistical distributions. We could obtain confidence intervals of similarity distance for the same and different persons, and optimal thresholds to minimize two kinds of error rates for distance distributions. It is found that the two confidence intervals of the same and different persons are not overlapped and that the optimal threshold locates between two confidence intervals. Hence an alternative statistical matching method can be suggested by using nonoverlapped confidence intervals and optimal thresholds obtained from the distributions of similarity distances.

Trends in statistical methods in articles published in Archives of Plastic Surgery between 2012 and 2017

  • Han, Kyunghwa;Jung, Inkyung
    • Archives of Plastic Surgery
    • /
    • v.45 no.3
    • /
    • pp.207-213
    • /
    • 2018
  • This review article presents an assessment of trends in statistical methods and an evaluation of their appropriateness in articles published in the Archives of Plastic Surgery (APS) from 2012 to 2017. We reviewed 388 original articles published in APS between 2012 and 2017. We categorized the articles that used statistical methods according to the type of statistical method, the number of statistical methods, and the type of statistical software used. We checked whether there were errors in the description of statistical methods and results. A total of 230 articles (59.3%) published in APS between 2012 and 2017 used one or more statistical method. Within these articles, there were 261 applications of statistical methods with continuous or ordinal outcomes, and 139 applications of statistical methods with categorical outcome. The Pearson chi-square test (17.4%) and the Mann-Whitney U test (14.4%) were the most frequently used methods. Errors in describing statistical methods and results were found in 133 of the 230 articles (57.8%). Inadequate description of P-values was the most common error (39.1%). Among the 230 articles that used statistical methods, 71.7% provided details about the statistical software programs used for the analyses. SPSS was predominantly used in the articles that presented statistical analyses. We found that the use of statistical methods in APS has increased over the last 6 years. It seems that researchers have been paying more attention to the proper use of statistics in recent years. It is expected that these positive trends will continue in APS.