• International Journal of Fuzzy Logic and Intelligent Systems
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• 제5권3호
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• pp.263-267
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• 2005

Building classifiers for financial real-world classification problems is often plagued by severely overlapping and highly skewed class distribution. New performance measures such as receiver operating characteristic (ROC) curve and area under ROC curve (AUC) have been recently introduced in evaluating and building classifiers for those kind of problems. They are, however, in-effective to evaluation of classifier's discrimination performance in a particular class of the classification problems that interests lie in only a local operating range of the classifier, In this paper, a new method is proposed that enables us to directly improve classifier's discrimination performance at a desired local operating range by defining and optimizing a partial area under ROC curve or domain-specific curve, which is difficult to achieve with conventional classification accuracy based learning methods. The effectiveness of the proposed approach is demonstrated in terms of fraud detection capability in a real-world fraud detection problem compared with the MSE-based approach.

• 한국광학회지
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• 제1권2호
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• pp.130-134
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• 1990

본 논문에서는 클래스 판별(interclass discrimination) 광패턴 인식을 위해 pSDF(projection synthetic discriminant function)를 기반으로 한 이미지를 구현하고, 비선형 상관기인 이진결합변환 상관기를 이용하였다. 비선형 상관기의 공간 주파수 영역에서 이진위상필터(binary phase only filter) 합성법을 도입하여 실시간 입력이 가능한 액정 표시 소자(liquid crystal device)를 사용하였다. 광패턴 인식 실험결과, 두 클래스간의 상관 첨두치 세기가 2배 차이가 나서 판별 능력이 우수함을 알 수 있었다.

• 한국사회복지학
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• 제59권4호
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• pp.191-216
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• 2007

본 연구는 가족과의 관계 속에서 형성되는 여성 빈곤의 문제, 특히 남성 생계부양자 규범에 의해 여성들이 어떻게 자원배분과 자원통제에서 배제되어 빈곤에 취약해지게 되었는지 살펴보고자 하였다. 이를 위해 이혼경험이 있는 저소득 여성가구주 10명의 생애사를 분석하였다. 저소득 여성가구주들이 빈곤층에 이르게 되기까지 빈곤경로에 있어서 차이가 있는 것으로 나타났다. 여성가구주들이 빈곤에 이르게 되는 경로에 따라서 빈곤의 지속유형과 빈곤으로의 유입유형으로 분류하였다. 여성가구주의 빈곤은 출생 가족과 결혼 후 가족에서 자원형성과 자원배분, 자원통제에서의 차별을 통해서 빈곤에 취약해졌다. 남성 생계부양자 규범은 차별기제로 작동되었으나 빈곤화 경로 유형에 따라서 그것이 작동되는 방식에서 차이가 있음을 드러내었다. 빈곤의 지속 유형 사례 여성들에게 남성 생계부양자 규범은 상징적인 힘으로 작동되면서 이 여성들의 경제활동은 가족을 보살펴야 하는 아내 역할의 차원에서 수행되었다. 반면 빈곤으로의 유입 유형 사례 여성들에게 남성 생계부양자 규범은 피부양자의 위치로 자신을 인식함으로서 직업경력 단절 및 자원통제권을 상실하게 되면서 빈곤에 취약해졌다. 이러한 연구결과는 지금까지 여성가구주로 빈곤 논의에서 전제되고 있는 통념이 허구임을 밝힘으로써, 가족(The Family)만 유지된다면 여성은 빈곤하지 않을 것이라는 기존 시각을 문제화하고 관점 전환의 필요성을 제안하고 있다는 점에서 연구의 의의를 찾을 수 있다.

• 한국정밀공학회지
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• 제16권12호
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• pp.119-125
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• 1999

This paper gives an overview of the various approaches to designing statistical pattern recognition scheme based on Bayes discrimination rule and the artificial neural networks for rotating machine condition classification. Concerning to Bayes discrimination rule, this paper contains the linear discrimination rule applied to classification into several multivariate normal distributions with common covariance matrices, the quadratic discrimination rule under different covariance matrices. Also we discribes k-nearest neighbor method to directly estimate a posterior probability of each class. Five features are extracted in time domain vibration signals. Employing these five features, statistical pattern classifier and neural networks have been established to detect defects on rotating machine. Four different cases of rotation machine were observed. The effects of k number and neural networks structures on monitoring performance have also been investigated. For the comparison of diagnosis performance of these two method, their recognition success rates are calculated form the test data. The result of experiment which classifies the rotating machine conditions using each method presents that the neural networks shows the highest recognition rate.

• 품질경영학회지
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• 제36권2호
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• pp.36-44
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• 2008

In this paper a novel feature extraction and selection is carried out in order to improve the discriminating capability between healthy and damaged structure using vibration signals. Although many feature extraction and selection algorithms have been proposed for vibration signals, most proposed approaches don't consider the discriminating ability of features since they are usually in unsupervised manner. We proposed a novel feature extraction and selection algorithm selecting few wavelet coefficients with higher class discriminating capability for damage detection and class visualization. We applied three class separability measures to evaluate the features, i.e. T test statistics, divergence, and Bhattacharyya distance. Experiments with vibration signals from truss structure demonstrate that class separabilities are significantly enhanced using our proposed algorithm compared to other two algorithms with original time-based features and Fourier-based ones.

• Journal of the Korean Statistical Society
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• 제30권2호
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• pp.247-263
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• 2001

This paper concerns a problem of classification based on training dta. A framework of information geometry is given to elucidate the characteristics of discriminant functions including logistic discrimination and AdaBoost. We discuss a class of loss functions from a unified viewpoint.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권3호
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• pp.1243-1263
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• 2018

The two-stage linear discrimination analysis (TSLDA) is a feature extraction technique to solve the small size sample problem in the field of image recognition. The TSLDA has retained all subspace information of the between-class scatter and within-class scatter. However, the feature information in the four subspaces may not be entirely beneficial for classification, and the regularization procedure for eliminating singular metrics in TSLDA has higher time complexity. In order to address these drawbacks, this paper proposes an improved two-stage linear discriminant analysis (Improved TSLDA). The Improved TSLDA proposes a selection and compression method to extract superior feature information from the four subspaces to constitute optimal projection space, where it defines a single Fisher criterion to measure the importance of single feature vector. Meanwhile, Improved TSLDA also applies an approximation matrix method to eliminate the singular matrices and reduce its time complexity. This paper presents comparative experiments on five face databases and one handwritten digit database to validate the effectiveness of the Improved TSLDA.

• 대한전자공학회논문지
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• 제27권11호
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• pp.111-118
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• 1990

본 논문에서는 pSDF(projection synthetic discriminant function)공간 불변 필터 개념을 적용하여 기준 이미지를 구현하고, 공간 평면 상관기인 이진 결합 변환 상관기를 이용하여 동일 클래스 인식 및 클래스 판별을 위한 광 패턴 인식을 수행하였다. 컴퓨터 시뮬레이션 결과, 이진 결합 변환 상관기가 기존의 결합 변환 상관기보다 상관 첨두치 세기, 상관 첨두치 세기대 부로브비, 신호대 잡음비, 상관폭 부분에서 뛰어난 상관 특성을 보였다. 이진 결합 변환 상관기를 이용한 광 패턴 인식 실험을 한 결과, 동일 클래스 인식인 경우 $4.1~9.6{\%}$ 오차 범위 내에서 상관 첨두지 세기가 일정하게 나타났으며, 클래스 판별인 경우 두 클래스간의 상관 첨두지 세기가 2배 차이가 나서 판별 능력이 우수함을 알 수 있었다.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.4106-4106
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• 2001

A method to discriminate human gallstones by nea. infrared(NIR) spectrometry using a soft independent modeling of class analogy (SIMCA) has been studied. The fifty NIR spectra of gallstones in the wavenumber range from 4500 to 10,000 cm$\^$-1/ were measured. The forty samples were classified to three classes, cholesterol stone, calcium bilirubinate stone and calcium carbonate stone according to the contents of major components in each gallstone. The training set which contained objects of the different known class was constructed using forty NIR spectra and the test set was made with ten different gallstone spectra. The number of important principal components(PCs) to describe the class was determined by cross validation in order to improve the decision criterion of the SIMCA for the training set. The score plots of the class training set whose objects belong to the other classes were inspected. The critical distance of each class was computed using both the Euclidean distance and the Mahalanobis distance at a proper level of significance(${\alpha}$). Two methods were compared with respect to classification and their robustness towards the number of PCs selected to describe different classes.

• 비교문화연구
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• 제29권
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• pp.315-339
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• 2012

The Chilean educative policies as the Voucher System and the privatization have been almost same from the Pinochet government and the ones of "Concertacion" or "Democratic Alliances" until now. Because the neoliberal regime has dominated principally in Chile the area of the education. In this study first of all I will analyze the procedures of the violent repression of the leftist politicians and the intellectuals of the universities by the Pinochet government. And the importance of the reform of the law of education in 1980 was emphasized and the other one in 1990 one day before the retirement of Pinochet. We can comprehend the fact that the education would have been used as a tool to achieve the development of the country and the economic one sacrificing the public and equalitarian values of the education. And the competence, the efficiency and the quality of the education have been emphasized through the policies as example the rights of the selection of the schools by the parents as like a product in the market. But the result was the enormorors expansion of the private education not only in the secondary schools but also in the universities. And also has been intensified "the segregation and the discrimination" of the students jerarquitized by the different social-economic levels of the parents. The Chilean people including the middle class did not realize rightly the inherent problems of the neoliberal regime having the equivocation as if the private schools should have been better than the public ones. However the high level of the public university education became to be dominated by the acomodated class. This was the cause of the last year's great scale of the demonstration of the Chilean students. The most important thing is that these matters was agravated not by the Pinochet government but by the ones of "Concertacion" or "Democratic Alliances". Because these governments tried to maintain the neoliberal regime by means of the education only arranging the small problems or contratiempos.