• Title/Summary/Keyword: discrimination accuracy

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Optimal Criterion of Classification Accuracy Measures for Normal Mixture (정규혼합에서 분류정확도 측도들의 최적기준)

  • Yoo, Hyun-Sang;Hong, Chong-Sun
    • Communications for Statistical Applications and Methods
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    • v.18 no.3
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    • pp.343-355
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    • 2011
  • For a data with the assumption of the mixture distribution, it is important to find an appropriate threshold and evaluate its performance. The relationship is found of well-known nine classification accuracy measures such as MVD, Youden's index, the closest-to-(0, 1) criterion, the amended closest-to-(0, 1) criterion, SSS, symmetry point, accuracy area, TA, TR. Then some conditions of these measures are categorized into seven groups. Under the normal mixture assumption, we calculate thresholds based on these measures and obtain the corresponding type I and II errors. We could explore that which classification measure has minimum type I and II errors for estimated mixture distribution to understand the strength and weakness of these classification measures.

Identification of Transformed Image Using the Composition of Features

  • Yang, Won-Keun;Cho, A-Young;Cho, Ik-Hwan;Oh, Weon-Geun;Jeong, Dong-Seok
    • Journal of Korea Multimedia Society
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    • v.11 no.6
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    • pp.764-776
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    • 2008
  • Image identification is the process of checking whether the query image is the transformed version of the specific original image or not. In this paper, image identification method based on feature composition is proposed. Used features include color distance, texture information and average pixel intensity. We extract color characteristics using color distance and texture information by Modified Generalized Symmetry Transform as well as average intensity of each pixel as features. Individual feature is quantized adaptively to be used as bins of histogram. The histogram is normalized according to data type and it is used as the signature in comparing the query image with database images. In matching part, Manhattan distance is used for measuring distance between two signatures. To evaluate the performance of the proposed method, independent test and accuracy test are achieved. In independent test, 60,433 images are used to evaluate the ability of discrimination between different images. And 4,002 original images and its 29 transformed versions are used in accuracy test, which evaluate the ability that the proposed algorithm can find the original image correctly when some transforms was applied in original image. Experiment results show that the proposed identification method has good performance in accuracy test. And the proposed method is very useful in real environment because of its high accuracy and fast matching capacity.

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Patient Group Study to Improve the Accuracy of QSCC II+ (QSCC II+의 진단정확률 향상을 위한 환자군 연구)

  • Kang, Minsu;Oh, Jiwon;Lee, Hyeri;Lee, Junhee
    • Journal of Sasang Constitutional Medicine
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    • v.31 no.3
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    • pp.48-65
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    • 2019
  • Background Several attempts have been made to accurately diagnose the Sasnag Constitution. One of these attempts is to use a questionnaire. Questionnaire for the Sasang Constitution Classification(QSCC) has been revised several times and now used as QSCC II+. This study was designed to improve the accuracy of the revised Questionnaire for the Sasang Constitution Classification(QSCC II+). Method 1,054 people were gathered for this study and analyzed to check discrimination ability of current discriminant function of QSCC II+. They were outpatients who visited the hospital and the constitution was confirmed by the specialist of Sasang Constitutional Medicine. Results Accuracy of QSCC II+ at Soeumin was improved from 74.9% to 79.3%, and there were no significant difference at Soyangin and Taeumin. Conclusion New discriminant function was constructed through discriminant analysis. And the accuracy of QSCC II+ was generally improved, especially in Soeumin.

The accuracy of the depth perception of 3-dimensional images (이안식 입체영상에서 심도지각의 정확성에 관한 연구)

  • Cho, Am
    • Journal of the Ergonomics Society of Korea
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    • v.13 no.1
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    • pp.37-46
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    • 1994
  • The accurate error size and discrimination region in the perception of depth amount from 3-dimensional images by the human visual system will be the basic data for the utilization and application of the binocular 3- eimensional image system. This paper is focused on studying the accuracy of the depth amount perceived from 3- dimensional images by the human visual system. From the performed experiment, the following results have been obtained: (1) The depth amount perceived from the binocular 3- dimensional images has been displayed by a proper scale of distance, and found to be imprecise and also have a large variance. (2) In utilizing the binocular 3-dimensional image system, it seems more appropriate to make the images viewed outward rather than inward from the screen in the regard of error and variance. (3) The binocular 3-dimensional image system can be effectively applied to displaying unreal space, for example, the layout of room in design, from the viewpoint of perception characteristics of depth amount.

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Comparison of Off-the-Shelf DCNN Models for Extracting Bark Feature and Tree Species Recognition Using Multi-layer Perceptron (수피 특징 추출을 위한 상용 DCNN 모델의 비교와 다층 퍼셉트론을 이용한 수종 인식)

  • Kim, Min-Ki
    • Journal of Korea Multimedia Society
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    • v.23 no.9
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    • pp.1155-1163
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    • 2020
  • Deep learning approach is emerging as a new way to improve the accuracy of tree species identification using bark image. However, the approach has not been studied enough because it is confronted with the problem of acquiring a large volume of bark image dataset. This study solved this problem by utilizing a pretrained off-the-shelf DCNN model. It compares the discrimination power of bark features extracted by each DCNN model. Then it extracts the features by using a selected DCNN model and feeds them to a multi-layer perceptron (MLP). We found out that the ResNet50 model is effective in extracting bark features and the MLP could be trained well with the features reduced by the principal component analysis. The proposed approach gives accuracy of 99.1% and 98.4% for BarkTex and Trunk12 datasets respectively.

Study on Highly Accuracy Quality Evaluation of Spot Weld by use of Image Processing Technique

    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.5 no.4
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    • pp.38-46
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    • 1996
  • This paper discusses the feasibility of Ultrasonic Nondestructive Evaluation (UNDE) technique for sport weld quality. Ultrasonic c-scan image assisted by image processing technique was used for Nondestructive Evaluation(NDE) of spot weld quality. Ultrasonic testing results obtained were confirmed and compared by Optical Microscope and SAM(Scanning Acoustic Mircroscope) observation of the spot-weld cross section, The results show that the nugget dinameter can be successfully measured with the accuracy of 0.5mm. It was ascertained that ultrasonic c-scan technique is very effective method for the sake of the approach to the quantitative measurement of nugget diameter and the discrimination of the corona bond from nugget. Additional support for the above conclusions is provided by the results for galvanized steel. The ultrasonic results for galvanized welds generally correspond to the results for uncoated steel. Finally, it was found that the above-mentioned technique can be sufficiently applied to NDE method for securing the Quality Assurance(QA) of spot welded products in production line.

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The accuracy of the depth perception of 3-dimensional images (이안식 입체영상에서 심도지각의 정확성에 관한 연구)

  • Cho, Am
    • Proceedings of the ESK Conference
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    • 1994.04a
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    • pp.19-31
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    • 1994
  • The accurate error size and discrimination region in the perception of depth amount from 3- dimensional images by the human visual system will be the basic data for the utilization and application of the binocular 3 - Dimensional image system. This paper is focused on studying the accuracy of the depth amount perceived from 3-dimensional images by the human visual system. From the performed experiment, the following results have been obtained: (1) The depth amount perceived from the binocular 3-dimensional images has been displayed by a proper scale of distance, and found to be imprecise and also have a large variance. (2) In utilizing the binocular 3-dimensional image system, it seems more appropriate to make the images viewed outward rather than inward from the screen in the regard of error and variance. (3) The binocular 3- dimensional image system can be effectively applied to displaying unreal space, for example, the layout of room in design, from the viewpoint of perception characteristics of depth amount.

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Synergic Effect of using the Optical and Radar Image Data for the Land Cover Classification in Coastal Region

  • Kim, Sun-Hwa;Lee, Kyu-Sung
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.1030-1032
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    • 2003
  • This study a imed to analyze the effect of combined optical and radar image for the land cover classification in coastal region. The study area, Gyeonggi Bay area has one of the largest tidal ranges and has frequent land cover changes due to the several reclamations and rather intensive land uses. Ten land cover types were classified using several datasets of combining Landsat ETM+ and RADARSAT imagery. The synergic effects of the merged datasets were analyzed by both visual interpretation and an ordinary supervised classification. The merged optical and SAR datasets provided better discrimination among the land cover classes in the coastal area. The overall classification accuracy of merged datasets was improved to 86.5% as compared to 78% accuracy of using ETM+ only.

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Ultrasonic C-scan Technique for Nondestructive Evaluation of Spot Weld Quality (Spot용접 접합면의 초음파 비파괴평가 기법 제 1보 C-scan 기법을 중심으로)

  • Park, Ik-Gun
    • Journal of the Korean Society for Nondestructive Testing
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    • v.14 no.2
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    • pp.112-121
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    • 1994
  • This paper discusses the feasibility of ultrasonic C-scan technique for nondestructive evaluation of spot weld quality. Ultrasonic evaluation for spot weld quality was performed by immersion method with the mechanical and the electronic scanning of point-focussed ultrasonic beam(25 MHz). For the sake of the approach to the quantitative measurement of nugget diameter and the discrimination of the corona bond from nugget, preliminary infinitesimal gap experiment by newton ring is tried in order to set up the optimum ultrasonic test condition. Ultrasonic image data obtained were confirmed and compared by optical microscope and SAM(Scanning Acoustic Microscope) observation of the spot-weld cross section. The results show that the nugget diameter can be measured with the accuracy of 1.0mm, and voids included in nugget can be detected to $10{\mu}m$ extent with simplicity and accuracy. Finally, it was found that it is necessary to make a profound study of definite discrimination of corona bond from nugget and the approach of quantitative evaluation of nugget diameter by utilizing the various image processing techniques.

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Are p53 Antibodies a Diagnostic Indicator for Patients with Oral Squamous Cell Carcinoma? Systematic Review and Meta-Analysis

  • Yang, Zhi-Cheng;Ling, Li;Xu, Zhi-Wei;Sui, Xiao-Dong;Feng, Shuang;Zhang, Jun
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.1
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    • pp.109-115
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    • 2016
  • Background: P53 has been reported to be involved with tumorigenesis and has also been implicated as a significant biomarker in oral squamous cell carcinoma(OSCC). However, the diagnostic value of p53 antibodies remains controversial; hence, we comprehensively and quantitatively assessed the potential in the present systematic review. Materials and Methods: A comprehensive search was performed using PubMed and Embase, up to October 31, 2014, without language restriction. Studies were assessed for quality using QUADAS (quality assessment of studies of diagnostic accuracy). The positive likelihood ratio (PLR) and negative likelihood ratio (NLR) were pooled separately and compared with overall accuracy measures using diagnostic odds ratios (DORs) and symmetric summary receiver operating characteristic (SROC) curves. Results: Of 150 studies initially identified, 7 eligible regarding serum p53 antibodies met the inclusion criteria. Some 85.7% (6/7) were of relatively high quality (QUADAS $score{\geq}7$). The summary estimates for quantitative analysis of serum p53 antibody in the diagnosis of squamous cell carcinoma were: PLR 2.06 [95% confidence interval (CI) : 1.35-3.15], NLR 0.85 (95%CI: 0.80-0.90) and DOR 2.47 (95%CI: 1.49-4.12). Conclusions: This meta-analysis suggests that the use of s-p53-antibodies has potential diagnostic value with relatively high sensitivity and specificity for OSCC particularly with serum specimens for discrimination of OSCCs from healthy controls. However, its discrimination power is not perfect because of low sensitivity.