• Title/Summary/Keyword: statistical shape analysis

Search Result 408, Processing Time 0.029 seconds

Optical-Electronic Method for Statistical Evaluation of Human Corneal Endothelial Patterns (Human Corneal Endothelial 패턴의 통계적 분석을 위한 광전자적 방법)

  • Lee, Yim-Kul
    • Proceedings of the KOSOMBE Conference
    • /
    • v.1992 no.11
    • /
    • pp.58-62
    • /
    • 1992
  • Hybrid optical-electronic procedures are introduced for the automated estimation of cell parameters (e.g., size, size variation, and shape). Two different optical Fourier analysis procedures are applied to high contrast cell boundary patterns obtained from specular micrographs of the endothelial layer. In one case, a large number of cell patterns are illuminated to extract average cell size information. Once the average cell size information has been obtained, individual cells are illuminated to extract shape information.

  • PDF

WLDF: Effective Statistical Shape Feature for Cracked Tongue Recognition

  • Li, Xiao-qiang;Wang, Dan;Cui, Qing
    • Journal of Electrical Engineering and Technology
    • /
    • v.12 no.1
    • /
    • pp.420-427
    • /
    • 2017
  • This paper proposes a new method using Wide Line Detector based statistical shape Feature (WLDF) to identify whether or not a tongue is cracked; a cracked tongue is one of the most frequently used visible features for diagnosis in traditional Chinese Medicine (TCM). We first detected a wide line in the tongue image, and then extracted WLDF, such as the maximum length of each detected region, and the ratio between maximum length and the area of the detected region. We trained a binary support vector machine (SVM) based on the WLDF to build a classifier for cracked tongues. We conducted an experiment based on our proposed scheme, using 196 samples of cracked tongues and 245 samples of non-cracked tongues. The results of the experiment indicate that the recognition accuracy of the proposed method is greater than 95%. In addition, we provide an analysis of the results of this experiment with different parameters, demonstrating the feasibility and effectiveness of the proposed scheme.

Multistage Point and Confidence Interval Estimation of the Shape Parameter of Pareto Distribution

  • Hamdy, H.I.;Son, M.S.;Gharraph, M.K.;Rashad, A.M.
    • Communications for Statistical Applications and Methods
    • /
    • v.10 no.3
    • /
    • pp.1069-1086
    • /
    • 2003
  • This article presents the asymptotic theory of triple sampling procedure as pertain to estimating the shape parameter of Pareto distribution. Both point and confidence interval estimation are considered within the same inference unified framework. We show that this group sampling technique possesses the efficiency of Anscome (1953), Chow and Robbins (1965) purely sequential procedure as well as reduce the number of sampling operations by utilizing Stein (1945) two stages procedure. The analysis reveals that the technique performs excellent as far as the accuracy is concerned. The present problem differs from those considered by many authors, in multistage sampling, in that the final stage sample size and the parameter's estimate become highly correlated and therefore we adopted different approach.

Fixed-accuracy confidence interval estimation of P(X > c) for a two-parameter gamma population

  • Zhuang, Yan;Hu, Jun;Zou, Yixuan
    • Communications for Statistical Applications and Methods
    • /
    • v.27 no.6
    • /
    • pp.625-639
    • /
    • 2020
  • The gamma distribution is a flexible right-skewed distribution widely used in many areas, and it is of great interest to estimate the probability of a random variable exceeding a specified value in survival and reliability analysis. Therefore, the study develops a fixed-accuracy confidence interval for P(X > c) when X follows a gamma distribution, Γ(α, β), and c is a preassigned positive constant through: 1) a purely sequential procedure with known shape parameter α and unknown rate parameter β; and 2) a nonparametric purely sequential procedure with both shape and rate parameters unknown. Both procedures enjoy appealing asymptotic first-order efficiency and asymptotic consistency properties. Extensive simulations validate the theoretical findings. Three real-life data examples from health studies and steel manufacturing study are discussed to illustrate the practical applicability of both procedures.

Grain Size Analysis Using Morphological Properties of Grains (입자의 형태적 특성을 활용한 퇴적물 입도분석)

  • Choi, Kwang Hee
    • Journal of The Geomorphological Association of Korea
    • /
    • v.27 no.2
    • /
    • pp.19-28
    • /
    • 2020
  • Grain size analysis is the most basic procedure for identifying the origin, transport and sedimentation processes of sediments, and is widely used in geomorphology and sedimentology. Traditionally, grain size was determined by a sieve-pippette method, but the use of automated analyzers is increasing in recent years. These analyzers have many advantages over traditional techniques, but the measurement results are not always the same. It is still difficult to solve the pretreatment problem such as incomplete diffusion and residual organic matter, and inappropriate results may be obtained. This study compared image-based grain size analysis and sieve analysis to verify its statistical reliability, and conducted experiments to enhance the measurement accuracy using shape parameters. The results showed that the image-based analysis overestimated the grain size of sand dunes by about 7% compared to the sieve analysis, but the two measurements were not statistically different. In addition, by using shape parameters, such as aspect ratio, sphericity, and convexity, improved statistics were obtained compared to the original data. Using the morphological properties of the individual grains is a complementary method to the incomplete pretreatment of the grain size analysis process, and at the same time, it will contribute to improving the accuracy and reliability of the results.

Hybrid Type Vibration Power Flow Analysis Method Using SEA Parameters

  • Park, Young-Ho;Hong, Suk-Yoon
    • The Journal of the Acoustical Society of Korea
    • /
    • v.21 no.4E
    • /
    • pp.164-169
    • /
    • 2002
  • This paper proposes a hybrid method for vibration analysis in the medium to high frequency ranges using Power Flow Analysis (PFA) algorithm and Statistical Energy Analysis (SEA) coupling concepts. The main part of the developed method is the application of coupling loss factor (CLF) suggested in SEA to the power transmission, reflection coefficients in PI' A boundary conditions. The developed hybrid method shows very promising results with regard to the applications for the various damping loss factors in wide frequency ranges. And also this paper presents the applied results of Power Flow Finite Element Method (PFFEM) by forming the new joint element matrix with CLF to analyze the various plate structures in shape. The analytical results of automobile, complex plate structures show good agreement with those of PFFEM using the PFA coefficients.

Hybrid Type Vibration Power Flow Analysis Method Using SEA Parameters

  • 박영호;홍석윤
    • The Journal of the Acoustical Society of Korea
    • /
    • v.21 no.4
    • /
    • pp.164-164
    • /
    • 2002
  • This paper proposes a hybrid method for vibration analysis in the medium to high frequency ranges using Power Flow Analysis (PFA) algorithm and Statistical Energy Analysis (SEA) coupling concepts. The main part of the developed method is the application of coupling loss factor (CLF) suggested in SEA to the power transmission, reflection coefficients in PI' A boundary conditions. The developed hybrid method shows very promising results with regard to the applications for the various damping loss factors in wide frequency ranges. And also this paper presents the applied results of Power Flow Finite Element Method (PFFEM) by forming the new joint element matrix with CLF to analyze the various plate structures in shape. The analytical results of automobile, complex plate structures show good agreement with those of PFFEM using the PFA coefficients.

Development of 3D statistical mandible models for cephalometric measurements

  • Kim, Sung-Goo;Yi, Won-Jin;Hwang, Soon-Jung;Choi, Soon-Chul;Lee, Sam-Sun;Heo, Min-Suk;Huh, Kyung-Hoe;Kim, Tae-Il;Hong, Helen;Yoo, Ji-Hyun
    • Imaging Science in Dentistry
    • /
    • v.42 no.3
    • /
    • pp.175-182
    • /
    • 2012
  • Purpose: The aim of this study was to provide sex-matched three-dimensional (3D) statistical shape models of the mandible, which would provide cephalometric parameters for 3D treatment planning and cephalometric measurements in orthognathic surgery. Materials and Methods: The subjects used to create the 3D shape models of the mandible included 23 males and 23 females. The mandibles were segmented semi-automatically from 3D facial CT images. Each individual mandible shape was reconstructed as a 3D surface model, which was parameterized to establish correspondence between different individual surfaces. The principal component analysis (PCA) applied to all mandible shapes produced a mean model and characteristic models of variation. The cephalometric parameters were measured directly from the mean models to evaluate the 3D shape models. The means of the measured parameters were compared with those from other conventional studies. The male and female 3D statistical mean models were developed from 23 individual mandibles, respectively. Results: The male and female characteristic shapes of variation produced by PCA showed a large variability included in the individual mandibles. The cephalometric measurements from the developed models were very close to those from some conventional studies. Conclusion: We described the construction of 3D mandibular shape models and presented the application of the 3D mandibular template in cephalometric measurements. Optimal reference models determined from variations produced by PCA could be used for craniofacial patients with various types of skeletal shape.

An Anthropometric Study on the Korean Adult Head for the Development of 3D Craniofacial Shape (한국 성인의 3차원 두형개발을 위한 머리치수 연구)

  • Kim Hyesoo;Kim Jin Sook;Yi Kyong-Hwa;Park Sejin
    • Journal of the Korean Home Economics Association
    • /
    • v.43 no.6 s.208
    • /
    • pp.13-25
    • /
    • 2005
  • The purpose of this study was to analyse craniofacial shape by 3D scanner for Korean adult head shape by age group. The heads of 836 adults were measured by 3D scanner, and the 25 obtained measurements were analyzed by statifical methods. The results can be summarized as follows. 1. From the basic statistical data analysis, the vertex-tagion and the length between the pupils were the longest in the subjects in their twenties, and decreased in elderly groups. 2. According to the analysis of the craniofacial proportion, the typical adult Korea head type was short-headed. 3. Statistically noticeable differences were found in the ectocanthion- opistcranion by the measurement of the left and the right sides of face in the age groups of the 20s, 30s, 40s, and 50s. 4. The order of factor analysis was as follows: the horizontal length, the perpendicular length and the width from the highest in the age group of the 20s, 30s, 40s, and 50s.

Study on torso body types of adult males over 178cm tall (178cm 이상의 키 큰 성인남성에 대한 체간부 체형 유형화 연구)

  • Kim, Min-jung
    • The Research Journal of the Costume Culture
    • /
    • v.30 no.5
    • /
    • pp.675-688
    • /
    • 2022
  • The purpose of this study is to analyze the body type characteristics of tall adult men aged 20 to 69 years to present base material on body dimensions for men's clothing companies. The research method comprised statistical analysis of 3D measurements after selecting items from the 8th Korean human body size survey related to the torso body types of 495 adult men who were at least 178cm tall. As a result, six factors were extracted, and the total explanatory variable of the entire factor was shown to be 80.499%. As a result of cluster analysis using this as an independent variable, three types were derived: Type 1, "a normal body type with an oval cross-sectional shape" (37.6%), with a larger vertical size and an oval chest cross-sectional shape compared to other types; Type 2: a "cylindrical thick body shape" (31.1%), which is the first stage of BMI obesity, with narrow shoulders and a cylindrical shape with a round cross-section; Type 3, "a body shape with broad shoulders and developed chest parts" (31.3%), with a horizontal size similar to Type 2 above the waist, but similar to Type 1 below. The results of this study are expected to be used as a basis for a clothing dimension system and clothing development for tall men reflecting the characteristics of the torso.