• 제목/요약/키워드: classification function

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Multivariate Gaussian 함수를 이용한 센서 네트워크의 수화 인식에의 적용 (Application of Sensor Network Using Multivariate Gaussian Function to Hand Gesture Recognition)

  • 김성호;한윤종;디아코네스쿠 보그다나
    • 제어로봇시스템학회논문지
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    • 제11권12호
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    • pp.991-995
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    • 2005
  • Sensor networks are the results of convergence of very important technologies such as wireless communication and micro electromechanical systems. In recent years, sensor networks found a wide applicability in various fields such as health, environment and habitat monitoring, military, etc. A very important step for these many applications is pattern classification and recognition of data collected by sensors installed or deployed in different ways. But, pattern classification and recognition are sometimes difficult to perform. Systematic approach to pattern classification based on modern teaming techniques like Multivariate Gaussian mixture models, can greatly simplify the process of developing and implementing real-time classification models. This paper proposes a new recognition system which is hierarchically composed of many sensor nodes haying the capability of simple processing and wireless communication. The proposed system is able to perform classification of sensed data using the Multivariate Gaussian function. In order to verify the usefulness of the proposed system, it was applied to hand gesture recognition system.

실무적 적용 관점에서 신뢰성 분포의 유형화 모형의 고찰 (Review of Classification Models for Reliability Distributions from the Perspective of Practical Implementation)

  • 최성운
    • 대한안전경영과학회지
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    • 제13권1호
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    • pp.195-202
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    • 2011
  • The study interprets each of three classification models based on Bath-Tub Failure Rate (BTFR), Extreme Value Distribution (EVD) and Conjugate Bayesian Distribution (CBD). The classification model based on BTFR is analyzed by three failure patterns of decreasing, constant, or increasing which utilize systematic management strategies for reliability of time. Distribution model based on BTFR is identified using individual factors for each of three corresponding cases. First, in case of using shape parameter, the distribution based on BTFR is analyzed with a factor of component or part number. In case of using scale parameter, the distribution model based on BTFR is analyzed with a factor of time precision. Meanwhile, in case of using location parameter, the distribution model based on BTFR is analyzed with a factor of guarantee time. The classification model based on EVD is assorted into long-tailed distribution, medium-tailed distribution, and short-tailed distribution by the length of right-tail in distribution, and depended on asymptotic reliability property which signifies skewness and kurtosis of distribution curve. Furthermore, the classification model based on CBD is relied upon conjugate distribution relations between prior function, likelihood function and posterior function for dimension reduction and easy tractability under the occasion of Bayesian posterior updating.

The Psychosomatic Disorders Pertaining to Dental Practice with Revised Working Type Classification

  • Shamim, Thorakkal
    • The Korean Journal of Pain
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    • 제27권1호
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    • pp.16-22
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    • 2014
  • Psychosomatic disorders are defined as disorders characterized by physiological changes that originate partially from emotional factors. This article aims to discuss the psychosomatic disorders of the oral cavity with a revised working type classification. The author has added one more subset to the existing classification, i.e., disorders caused by altered perception of dentofacial form and function, which include body dysmorphic disorder. The author has also inserted delusional halitosis under the miscellaneous disorders classification of psychosomatic disorders and revised the already existing classification proposed for the psychosomatic disorders pertaining to dental practice. After the inclusion of the subset (disorders caused by altered perception of dentofacial form and function), the terminology "psychosomatic disorders of the oral cavity" is modified to "psychosomatic disorders pertaining to dental practice".

소프트맥스 함수 특성을 활용한 침입탐지 모델의 공격 트래픽 분류성능 향상 방안 (Improvement of Attack Traffic Classification Performance of Intrusion Detection Model Using the Characteristics of Softmax Function)

  • 김영원;이수진
    • 융합보안논문지
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    • 제20권4호
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    • pp.81-90
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    • 2020
  • 현실 세계에서는 기존에 알려지지 않은 새로운 유형의 변종 공격이 끊임없이 등장하고 있지만, 인공신경망과 지도학습을 통해 개발된 공격 트래픽 분류모델은 학습을 실시하지 않은 새로운 유형의 공격을 제대로 탐지하지 못한다. 기존 연구들 대부분은 이러한 문제점을 간과하고 인공신경망의 구조 개선에만 집중한 결과, 다수의 새로운 공격을 정상 트래픽으로 분류하는 현상이 빈번하게 발생하여 공격 트래픽 분류성능이 심각하게 저하되었다. 한편, 다중분류 문제에서 각 클래스에 대한 분류가 정답일 확률을 결과값으로 출력하는 소프트맥스(softmax) 함수도 학습하지 않은 새로운 유형의 공격 트래픽에 대해서는 소프트맥스 점수를 제대로 산출하지 못하여 분류성능의 신뢰도 또는 정확도를 제고하는데 한계를 노출하고 있다. 이에 본 논문에서는 소프트맥스 함수의 이러한 특성을 활용하여 모델이 일정 수준 이하의 확률로 판단한 트래픽을 공격으로 분류함으로써 새로운 유형의 공격에 대한 탐지성능을 향상시키는 방안을 제안하고, 실험을 통해 효율성을 입증한다.

Carboxylesterases: Structure, Function and Polymorphism

  • Satoh, Tetsuo;Hosokawa, Masakiyo
    • Biomolecules & Therapeutics
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    • 제17권4호
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    • pp.335-347
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    • 2009
  • This review covers current developments in molecular-based studies of the structure and function of carboxylesterases. To allay the confusion of the classic classification of carboxylesterase isozymes, we have proposed a novel nomenclature and classification of mammalian carboxylesterases on the basis of molecular properties. In addition, mechanisms of regulation of gene expression of carboxylesterases by xenobiotics, and involvement of carboxylesterase in drug metabolism are also described.

면방정식의 고유치와 신경회로망을 이용한 거리영상의 분할과 분류 (Range Data Sementation and Classification Using Eigenvalues of Surface Function and Neural Network)

  • 정인갑;현기호;이진재;하영호
    • 전자공학회논문지B
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    • 제29B권7호
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    • pp.70-78
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    • 1992
  • In this paper, an approach for 3-D object segmentation and classification, which is based on eigen-values of polynomial function as their surface features, using neural network is proposed. The range images of 3-D objects are classified into surface primitives which are homogeneous in their intrinsic eigenvalue properties. The misclassified regions due to noise effect are merged into correct regions satisfying homogeneous constraints of Hopfield neural network. The proposed method has advantage of processing both segmentation and classification simultaneously.

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Bivariate ROC Curve and Optimal Classification Function

  • Hong, C.S.;Jeong, J.A.
    • Communications for Statistical Applications and Methods
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    • 제19권4호
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    • pp.629-638
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    • 2012
  • We propose some methods to obtain optimal thresholds and classification functions by using various cutoff criterion based on the bivariate ROC curve that represents bivariate cumulative distribution functions. The false positive rate and false negative rate are calculated with these classification functions for bivariate normal distributions.

Classification via principal differential analysis

  • Jang, Eunseong;Lim, Yaeji
    • Communications for Statistical Applications and Methods
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    • 제28권2호
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    • pp.135-150
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    • 2021
  • We propose principal differential analysis based classification methods. Computations of squared multiple correlation function (RSQ) and principal differential analysis (PDA) scores are reviewed; in addition, we combine principal differential analysis results with the logistic regression for binary classification. In the numerical study, we compare the principal differential analysis based classification methods with functional principal component analysis based classification. Various scenarios are considered in a simulation study, and principal differential analysis based classification methods classify the functional data well. Gene expression data is considered for real data analysis. We observe that the PDA score based method also performs well.

New Inference for a Multiclass Gaussian Process Classification Model using a Variational Bayesian EM Algorithm and Laplace Approximation

  • Cho, Wanhyun;Kim, Sangkyoon;Park, Soonyoung
    • IEIE Transactions on Smart Processing and Computing
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    • 제4권4호
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    • pp.202-208
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    • 2015
  • In this study, we propose a new inference algorithm for a multiclass Gaussian process classification model using a variational EM framework and the Laplace approximation (LA) technique. This is performed in two steps, called expectation and maximization. First, in the expectation step (E-step), using Bayes' theorem and the LA technique, we derive the approximate posterior distribution of the latent function, indicating the possibility that each observation belongs to a certain class in the Gaussian process classification model. In the maximization step, we compute the maximum likelihood estimators for hyper-parameters of a covariance matrix necessary to define the prior distribution of the latent function by using the posterior distribution derived in the E-step. These steps iteratively repeat until a convergence condition is satisfied. Moreover, we conducted the experiments by using synthetic data and Iris data in order to verify the performance of the proposed algorithm. Experimental results reveal that the proposed algorithm shows good performance on these datasets.

Discriminative Manifold Learning Network using Adversarial Examples for Image Classification

  • Zhang, Yuan;Shi, Biming
    • Journal of Electrical Engineering and Technology
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    • 제13권5호
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    • pp.2099-2106
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    • 2018
  • This study presents a novel approach of discriminative feature vectors based on manifold learning using nonlinear dimension reduction (DR) technique to improve loss function, and combine with the Adversarial examples to regularize the object function for image classification. The traditional convolutional neural networks (CNN) with many new regularization approach has been successfully used for image classification tasks, and it achieved good results, hence it costs a lot of Calculated spacing and timing. Significantly, distrinct from traditional CNN, we discriminate the feature vectors for objects without empirically-tuned parameter, these Discriminative features intend to remain the lower-dimensional relationship corresponding high-dimension manifold after projecting the image feature vectors from high-dimension to lower-dimension, and we optimize the constrains of the preserving local features based on manifold, which narrow the mapped feature information from the same class and push different class away. Using Adversarial examples, improved loss function with additional regularization term intends to boost the Robustness and generalization of neural network. experimental results indicate that the approach based on discriminative feature of manifold learning is not only valid, but also more efficient in image classification tasks. Furthermore, the proposed approach achieves competitive classification performances for three benchmark datasets : MNIST, CIFAR-10, SVHN.