• Title/Summary/Keyword: Statistical descriptors

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Estimation of Biological Action of Dioxins by Some Geometric Descriptors (기하학적 변수에 의한 다이옥신의 독성 예측)

  • Hwang, Inchul
    • Environmental Analysis Health and Toxicology
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    • v.14 no.3
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    • pp.103-111
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    • 1999
  • To effectively predict the lipophilicity, the aryl hydrocarbon receptor (AhR) affinity, and TEF (Toxic equivalency factor) of dioxins by geometrical descriptors, the multiple linear regression methods with the forward selection and backward elimination were employed with statistical validity. The lipophilicity, the Ah receptor binding affinity, and the toxic equivalency factor of dioxins could be predicted using some geometrical descriptors.

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Image Registration Based On Statistical Descriptors In Frequency Domain

  • Chang, Min-hyuk;Ahmad, Muhammad-Bilal;Lee, Cheul-hee;Chun, Jong-hoon;Park, Seung-jin;Park, Jong-an
    • Proceedings of the IEEK Conference
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    • 2002.07c
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    • pp.1531-1534
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    • 2002
  • Shape description and its corresponding matching algorithm is one of the main concerns in MPEG-7. In this paper, a new method is proposed for shape registration of 2D objects for MPEG-7 Shapes are recognized using the Hu statistical moments in frequency domain. The Hu moments are moment-based descriptors of planar shapes, which are invariant under general translation, rotational, scaling, and reflection transformation. The image is transformed into frequency domain using Fourier Transform. Annular and radial wedge distributions fur the power spectra are extracted. Different statistical features (Hu moments) are found f3r the power spectrum of each selected transformed individual feature. The Euclidean distance of the extracted moment descriptors of the features are found with respect to the shapes in the database. The minimum Euclidean distance is the candidate for the matched shape. The simulation results are performed on the test shapes of MPEG-7.

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Is it Possible to Predict the ADI of Pesticides using the QSAR Approach?

  • Kim, Jae Hyoun
    • Journal of Environmental Health Sciences
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    • v.38 no.6
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    • pp.550-560
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    • 2012
  • Objectives: QSAR methodology was applied to explain two different sets of acceptable daily intake (ADI) data of 74 pesticides proposed by both the USEPA and WHO in terms of setting guidelines for food and drinking water. Methods: A subset of calculated descriptors was selected from Dragon$^{(R)}$ software. QSARs were then developed utilizing a statistical technique, genetic algorithm-multiple linear regression (GA-MLR). The differences in each specific model in the prediction of the ADI of the pesticides were discussed. Results: The stepwise multiple linear regression analysis resulted in a statistically significant QSAR model with five descriptors. Resultant QSAR models were robust, showing good utility across multiple classes of pesticide compounds. The applicability domain was also defined. The proposed models were robust and satisfactory. Conclusions: The QSAR model could be a feasible and effective tool for predicting ADI and for the comparison of logADIEPA to logADIWHO. The statistical results agree with the fact that USEPA focuses on more subtle endpoints than does WHO.

Evaluation of Histograms Local Features and Dimensionality Reduction for 3D Face Verification

  • Ammar, Chouchane;Mebarka, Belahcene;Abdelmalik, Ouamane;Salah, Bourennane
    • Journal of Information Processing Systems
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    • v.12 no.3
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    • pp.468-488
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    • 2016
  • The paper proposes a novel framework for 3D face verification using dimensionality reduction based on highly distinctive local features in the presence of illumination and expression variations. The histograms of efficient local descriptors are used to represent distinctively the facial images. For this purpose, different local descriptors are evaluated, Local Binary Patterns (LBP), Three-Patch Local Binary Patterns (TPLBP), Four-Patch Local Binary Patterns (FPLBP), Binarized Statistical Image Features (BSIF) and Local Phase Quantization (LPQ). Furthermore, experiments on the combinations of the four local descriptors at feature level using simply histograms concatenation are provided. The performance of the proposed approach is evaluated with different dimensionality reduction algorithms: Principal Component Analysis (PCA), Orthogonal Locality Preserving Projection (OLPP) and the combined PCA+EFM (Enhanced Fisher linear discriminate Model). Finally, multi-class Support Vector Machine (SVM) is used as a classifier to carry out the verification between imposters and customers. The proposed method has been tested on CASIA-3D face database and the experimental results show that our method achieves a high verification performance.

A Study on Evaluation Method of Stream Naturalness for Ecological Restoration of Stream Corridors (우리나라 중소하천 코리도의 자연성 평가기법 연구)

  • 조용현
    • Journal of the Korean Institute of Landscape Architecture
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    • v.25 no.2
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    • pp.73-81
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    • 1997
  • The main purpose of this study was to develop a new method for evaluation of stream naturalness in order to appraise and prescribe for streams effectively in the process of ecological restoration of stream corridors. The results are as follows : 1) For this purpose six factors were selected on considering the spatial axes of stream corridor variation and total 20 descriptors about the physical structure were selected. 2) The calculation of S.N.I. for each segment was consisted of three steps, such as calculation of S.N.I.s of the individual descriptors, averaging all the descriptors's for each factor, and finally averaging the factors's for the Total S.N.I. 3) The evaluation unit was decided to be 100m size. The score system ranging 1~5 was adopted. Weighting parameters of factors were unified with each other. 4) A GIS model was adopted for classification, calculation, querying, analysing, and presenting S.N.I. information. And the format of S.N.I. maps including statistical graphs and other spatial watershed information was designed for the GIS odel. The naturalness of stream corridor was was investigated by the naturalness of habitat, and assessed by the descriptors focused on physical structure, therefore the S.N.I. can manifest prescriptions for restoration of the stream corridor. On the other hand because some evaluation factors such as water quality, water volume, fauna, flora, functions of stream exosystem has been excluded, S.N.I. could have some limits on representing the full aspects of stream naturalness. This evaluation method is hypothetical one, so it would be investigated through iterative applicatons.

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Person-Independent Facial Expression Recognition with Histograms of Prominent Edge Directions

  • Makhmudkhujaev, Farkhod;Iqbal, Md Tauhid Bin;Arefin, Md Rifat;Ryu, Byungyong;Chae, Oksam
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.12
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    • pp.6000-6017
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    • 2018
  • This paper presents a new descriptor, named Histograms of Prominent Edge Directions (HPED), for the recognition of facial expressions in a person-independent environment. In this paper, we raise the issue of sampling error in generating the code-histogram from spatial regions of the face image, as observed in the existing descriptors. HPED describes facial appearance changes based on the statistical distribution of the top two prominent edge directions (i.e., primary and secondary direction) captured over small spatial regions of the face. Compared to existing descriptors, HPED uses a smaller number of code-bins to describe the spatial regions, which helps avoid sampling error despite having fewer samples while preserving the valuable spatial information. In contrast to the existing Histogram of Oriented Gradients (HOG) that uses the histogram of the primary edge direction (i.e., gradient orientation) only, we additionally consider the histogram of the secondary edge direction, which provides more meaningful shape information related to the local texture. Experiments on popular facial expression datasets demonstrate the superior performance of the proposed HPED against existing descriptors in a person-independent environment.

Quantitative Structure Activity Relationship Prediction of Oral Bioavailabilities Using Support Vector Machine

  • Fatemi, Mohammad Hossein;Fadaei, Fatemeh
    • Journal of the Korean Chemical Society
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    • v.58 no.6
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    • pp.543-552
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    • 2014
  • A quantitative structure activity relationship (QSAR) study is performed for modeling and prediction of oral bioavailabilities of 216 diverse set of drugs. After calculation and screening of molecular descriptors, linear and nonlinear models were developed by using multiple linear regression (MLR), artificial neural network (ANN), support vector machine (SVM) and random forest (RF) techniques. Comparison between statistical parameters of these models indicates the suitability of SVM over other models. The root mean square errors of SVM model were 5.933 and 4.934 for training and test sets, respectively. Robustness and reliability of the developed SVM model was evaluated by performing of leave many out cross validation test, which produces the statistic of $Q^2_{SVM}=0.603$ and SPRESS = 7.902. Moreover, the chemical applicability domains of model were determined via leverage approach. The results of this study revealed the applicability of QSAR approach by using SVM in prediction of oral bioavailability of drugs.

Detection of Faces with Partial Occlusions using Statistical Face Model (통계적 얼굴 모델을 이용한 부분적으로 가려진 얼굴 검출)

  • Seo, Jeongin;Park, Hyeyoung
    • Journal of KIISE
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    • v.41 no.11
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    • pp.921-926
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    • 2014
  • Face detection refers to the process extracting facial regions in an input image, which can improve speed and accuracy of recognition or authorization system, and has diverse applicability. Since conventional works have tried to detect faces based on the whole shape of faces, its detection performance can be degraded by occlusion made with accessories or parts of body. In this paper we propose a method combining local feature descriptors and probability modeling in order to detect partially occluded face effectively. In training stage, we represent an image as a set of local feature descriptors and estimate a statistical model for normal faces. When the test image is given, we find a region that is most similar to face using our face model constructed in training stage. According to experimental results with benchmark data set, we confirmed the effect of proposed method on detecting partially occluded face.

Tracking of Moving Objects Using Morphological Segmentation, Statistical Moments and Hough Transform

  • Ahmad, Muhammad Bilal;Chang, Min-Hyuk;Park, Jong-An
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.1377-1381
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    • 2003
  • This paper describes real time object tracking of 3D objects in 2D image sequences. The moving objects are segmented from the image sequence using morphological operations. The moving objects are segmented by the method of differential image followed by the process of morphological dilation. The moving objects are recognized and tracked using statistical moments. The direction of moving objects are determined by the Hough transform. The straight lines in the moving objects are found with the help of Hough transform. The direction of the moving object is calculated from the orientation of the straight lines in the direction of the principal axes of the moving objects. The direction of the moving object and the displacement of the object in the image sequence is used to calculate the velocity of the moving objects. The simulation results of the proposed method are promising on the test images.

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Real-time Multi-Objects Recognition and Tracking Scheme (실시간 다중 객체 인식 및 추적 기법)

  • Kim, Dae-Hoon;Rho, Seung-Min;Hwang, Een-Jun
    • Journal of Advanced Navigation Technology
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    • v.16 no.2
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    • pp.386-393
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    • 2012
  • In this paper, we propose an efficient multi-object recognition and tracking scheme based on interest points of objects and their feature descriptors. To do that, we first define a set of object types of interest and collect their sample images. For sample images, we detect interest points and construct their feature descriptors using SURF. Next, we perform a statistical analysis of the local features to select representative points among them. Intuitively, the representative points of an object are the interest points that best characterize the object. in addition, we make the movement vectors of the interest points based on matching between their SURF descriptors and track the object using these vectors. Since our scheme treats all the objects independently, it can recognize and track multiple objects simultaneously. Through the experiments, we show that our proposed scheme can achieve reasonable performance.