• Proceedings of the Korean Society of Computer Information Conference
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• 2023.07a
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• pp.283-285
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• 2023

이상 탐지는 데이터에서 일반적인 범주에서 크게 벗어나는 인스턴스 또는 패턴을 식별하는 중요한 작업이다. 본 연구에서는 시계열 데이터의 특징 추출을 위한 비지도 학습 기반 방법과 정규화 흐름의 결합을 통한 이상 탐지 프레임워크를 제안한다. 특징 추출기는 1차원 합성곱 신경망 기반의 오토인코더로 구성되며, 정상적인 시퀀스로만 구성된 훈련 데이터를 압축하고 복원하는 과정을 통해 최적화된다. 추출된 시계열 데이터의 특징 맵은 가능도를 최대화하도록 훈련된 정규화 흐름의 입력으로 사용된다. 이와 같은 방식으로 훈련된 이상 탐지 시스템은 테스트 샘플에 대한 이상치를 계산하며, 최종적으로 임계값과의 비교를 통해 이상 여부를 예측한다. 성능 평가를 위해 시계열 이상 탐지를 위한 공개 데이터셋을 이용하여 공정하게 이상 탐지 성능을 비교하였으며, 실험 결과는 제안하는 정규화 흐름 기법이 시계열 이상 탐지 시스템에 활용될수 있는 잠재성을 시사한다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.2C
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• pp.272-282
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• 2004

This paper introduces a regularized mixed norm multi-channel image restoration algorithm using both within-and between- channel deterministic information. For each channel a functional which combines the least mean squares (LMS), the least mean fourth (LMF), and a smoothing functional is proposed. We introduce a mixed norm parameter that controls the relative contribution between the LMS and the LMF, and a regularization parameter defining the degree of smoothness of the solution, where both parameters are updated at each iteration according to the noise characteristics of each channel. The novelty of the proposed algorithm is that no knowledge of the noise distribution for each channel is required and that the parameters mentioned above are adjusted based on the partially restored image.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.4 s.304
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• pp.59-68
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• 2005

This paper proposes a face recognition under varying poses using local area obtained by side-view pose normalization. General normalization methods for face recognition under varying pose have a problem with the information about invisible area of face. Generally this problem is solved by compensation, but there are many cases where the image is distorted or features lost due to compensation .To solve this problem we normalize the face pose in side-view to reduce distortion that happens mainly in areas that have large depth variation. We only use undistorted area, removing the area that has been distorted by normalization. We consider two cases of yaw pose variation and pitch pose variation, and by experiments, we confirm the improvement of recognition performance.

• Journal of Intelligence and Information Systems
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• v.22 no.2
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• pp.1-11
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• 2016

Entani and Tanaka (2007) presented a new approach for obtaining interval evaluations suitable for handling uncertain data. Above all, their approach is characterized by the normalization of interval data and thus the elimination of redundant bounds. Further, interval global weights in AHP are derived by using such normalized interval data. In this paper, we present a heuristic method for finding extreme points of interval data, which basically extends the method by Entani and Tanaka (2007), and also helps to obtain normalized interval data. In the second part of this paper, we show that the solutions to the linear program for interval global weights can be obtained by a simple inspection. In the meantime, the absolute dominance proposed by the authors is extended to pairwise dominance which makes it possible to identify at least more dominated alternatives under the same information.

• Journal of The Korean Association of Information Education
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• v.22 no.2
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• pp.195-203
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• 2018

This thesis is to presented a theoretical fundamental of an assessment criteria available to a conventional curriculum because informatics subject matter education became it. We analyzed Bloom's Knowledge Dimension, Taxonomy that have suggested most general theoretical base in the educational assessment area. Also a programming area which can improve computational thinking can be the most important chapter of the informatics subject matter. Thus this thesis applied Bloom's theory to KAIE's informatics subject matter curriculum made by 2017. And the result of the qualitative research through the expert panel was 14 items, 87% of Conceptual, Procedural Knowledge and 12 items, 75% of Understand, Apply Taxonomy of Bloom's Theories in the 16 items of the curriculum outlines. Applying Bloom Criteria to like these can provide theoretical fundamental of assessment trend, development of assessment tool requested in the conventional education.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.22 no.4
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• pp.279-285
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• 2010

In the process of the probabilistic-based design on the coastal structures, the probability density function (pdf) of tidal elevation data is assumed as the normal distribution function. The pdf shape of tidal elevation data, however, is better-fitted to the double-peak normal distribution function and the equivalent mean and standard deviation (SD) estimation process based on the equivalent normal distribution is required. The equivalent mean and SD (equivalent parameters) are different with the mean and SD (normal parameters) estimated in the condition that the pdf of tidal elevation is normal distribution. In this study, the difference, i.e., estimation error, between equivalent parameters and normal parameters is compared and analysed. The difference is increased as the tidal elevation and its range are increased. The mean and SD differences in the condition of the tidal elevation is ${\pm}400cm$ are above 100 cm and about 80~100 cm, respectively, in Incheon station. Whereas, the mean and SD differences in the condition of the tidal elevation is ${\pm}60cm$ are very small values in the range of 2~4 cm, in Pohang station.

• Journal of Labour Economics
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• v.24 no.1
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• pp.177-205
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• 2001

This study investigates a long-tenn effect of labor career during middle life on the retirement process and income status later in life course. Two waves of KLIPS (Korean Labor Longitudinal Panel Survey) data sets collected in 1998 and 1999, are employed, which include detailed information on economic activities among those aged 15 and over. Results show that temporary, contracted workers during middle life not only have higher risk of job loss and poverty than those in permanent work status but also they are more likely to experience a stressful retirement process later in life course.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.6
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• pp.3557-3563
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• 2014

Korean National Level Kindergarten Curriculum does not include English education in regular class time. On the other hand, more than 90% kindergarteners are taught English. This study examined the Native English Teachers' (NETs') cultural aspects of their teaching at regular kindergartens in Korea. Data was collected through in-depth interviews with four NETs who were working at regular kindergartens in Korea, their partner Local English Teachers (LETs) and kindergarten principals. All interview data was transcribed and categorized based on the grounded theory method. The results showed that NETs are not required to be culturally prepared to teach in Korean kindergartens. Consequently, most of them do not consider the students' culture in their teaching activities. Moreover, Korean kindergartens, where research participants work, are not prepared well to invite NETs into their regular curriculum. These results will have significant implications on Korean kindergarten's English education practice.

• Journal of Korea Multimedia Society
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• v.12 no.3
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• pp.383-396
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• 2009

Bone age assessment has been widely used in pediatrics to identify endocrine problems of children. Since the number of trained doctors is far less than the demands, there has been numerous requests for automatic estimation of bone age. Therefore, in this paper, we propose an automatic bone age assessment method that utilizes pattern classification techniques. The proposed method consists of three modules; a finger segmentation module, a normalized shape model generation module and a bone age estimation module. The finger segmentation module segments fingers and epiphyseal regions by means of various image processing algorithms. The shape model abstraction module employ ASM to improves the accuracy of feature extraction for bone age estimation. In addition, SVM is used for estimation of bone age. Features for the estimation include the length of bone and the ratios of bone length. We evaluated the performance of the proposed method through statistical analysis by comparing the bone age assessment results by clinical experts and the proposed automatic method. Through the experimental results, the mean error of the assessment was 0.679 year, which was better than the average error acceptable in clinical practice.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.5
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• pp.600-608
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• 2020

Machine learning constructs an objective function from learning data, and predicts the result of the data generated by checking the objective function through test data. In machine learning, input data is subjected to a normalisation process through a preprocessing. In the case of numerical data, normalization is standardized by using the average and standard deviation of the input data. In the case of nominal data, which is non-numerical data, it is converted into a one-hot code form. However, this preprocessing alone cannot solve the problem. For this reason, we propose a method that uses ontology to normalize input data in this paper. The test data for this uses the received signal strength indicator (RSSI) value of the Wi-Fi device collected from the mobile device. These data are solved through ontology because they includes noise and heterogeneous problems.