• 제어로봇시스템학회논문지
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• 제13권1호
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• pp.52-57
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• 2007

In this paper we proposed multi-directional matching windows combined by multi-dimensional feature vector matching, which uses not only intensity values but also multiple feature values, such as variance, first and second derivative of pixels. Multi-dimensional feature vector matching has the advantage of compensating the drawbacks of area-based stereo matching using one feature value, such as intensity. We define matching cost of a pixel by the minimum value among eight multi-dimensional feature vector distances of the pixels expanded in eight directions having the interval of 45 degrees. As best stereo matches, we determine the two points with the minimum matching cost within the disparity range. In the experiment we used aerial imagery and IKONOS satellite imagery and obtained more accurate matching results than that of conventional matching method.

• 대한전자공학회논문지SP
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• 제38권1호
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• pp.11-18
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• 2001

본 논문에서는 얼굴영상 압축을 위한 알고리즘으로 삼각특징 추출과 GHA를 이용한 압축 알고리즘을 제안한다. 특징추출에서 입력영상을 8개의 삼각형으로 분할한 다음 데이터의 취득순서를 설정하여 영상을 분할하면서도 위치정보를 보존할 수 있는 알고리즘을 제안하고, 압축을 위해 GHA를 도입함으로써 복원 시 생기는 블록화 현상을 대폭 개선하였으며 얼굴의 윤곽과 이목구비 등 얼굴의 전체적인 형태를 압축 알고리즘에 반영할 수 있었다. 기존의 블록기반 K-means 알고리즘과 얼굴영상을 분할하지 않고 전체를 입력으로 사용하는 알고리즘과의 비교실험결과 제안된 방법의 성능이 가장 우수함을 볼 수 있었다.

• 천문학회지
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• 제18권2호
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• pp.100-110
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• 1985

The HI features associated with HII regions and radio sources in the galactic-plane are searched in the Maryland-Green Bank Galactic 21-cm Line Survey. Among the twenty-eight such objects, twenty-five show HI depression features, two no feature, and an emission feature with excess HI brightness temperature. Most of these feature are surrounded by strong HI emissions. The depth of the HI depression is proportional to the radio continuum brightness temperature. The angular dimensions of the HI feature and radio source are comparable. The small HI depressions shown at the positions of HII region located in the outer solar circle are considered to be HI self-absorption features of very cold HI gas.

• IEIE Transactions on Smart Processing and Computing
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• 제5권3호
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• pp.153-163
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• 2016

Local feature extraction methods for images and videos are widely applied in the fields of image understanding and computer vision. However, robust features are detected differently when using the latest feature detectors and descriptors because of diverse image environments. This paper analyzes various feature extraction methods by summarizing algorithms, specifying properties, and comparing performance. We analyze eight feature extraction methods. The performance of feature extraction in various image environments is compared and evaluated. As a result, the feature detectors and descriptors can be used adaptively for image sequences captured under various image environments. Also, the evaluation of feature detectors and descriptors can be applied to driving assistance systems, closed circuit televisions (CCTVs), robot vision, etc.

• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 2001년도 The Pacific Aisan Confrence On Intelligent Systems 2001
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• pp.421-427
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• 2001

In this paper, a method for selection of the optimal feature vectors is proposed for the classification of closed 2D shapes using the bispectrum of a contour sequence. The bispectrum based on third order cumulants is applied to the contour sequences of the images to extract feature vectors for each planar image. These bispectral feature vectors, which are invariant to shape translation, rotation and scale transformation, can be used to represent two-dimensional planar images, but there is no certain criterion on the selection of the feature vectors for optimal classification of closed 2D images. In this paper, a new method for selecting the optimal bispectral feature vectors based on the variances of the feature vectors. The experimental results are presented using eight different shapes of aircraft images, the feature vectors of the bispectrum from five to fifteen and an weighted mean fuzzy classifier.

• 한국조경학회:학술대회논문집
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• 한국조경학회 2007년도 Journal of Landscape Architecture in Asia Vol.3
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• pp.151-156
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• 2007

The Eight Scenery, as a traditional landscape to today, gradually caught the concern of landscape scholars, as well became the mutual cultural wealth of South Korea, China and Japan even of the whole Asia. The Yanjing Eight Scenery firstly originated from the Jin dynasty is an important representation of Eight Scenery culture in Scenic Spots and Historical Sites of China. The transition process of Yanjing Eight Scenery is examined in this thesis, and the cause of such change is also analyzed. Moreover, the landscape content of Yanjing Eight Scenery is classified in detail, and the succession of the landscape architecture of the Yanjing Eight Scenery style under the traditional culture is analyzed from the aspects of rebuilding pavilion, landscape arrangement, building, and new landscape architecture rebuilt followed the religious, the plant landscape and the traditional culture based on the classification. Beijing regional culture has influenced Yanjing Eight Scenery by its classification, the landscape evaluation, and the analysis of the landscape feature, in addition, this paper searches for the model to research the Eight Scenery culture in each country of Asia.

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2008년도 제39차 동계학술발표논문집 16권2호
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• pp.49-54
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• 2009

A fuzzy weighted mean method on a 2D shape recognition system is introduced in this paper. The bispectrum based on third order cumulant is applied to the contour sequence of each image for the extraction of a feature vector. This bispectral feature vector, which is invariant to shape translation, rotation and scale, represents a 2D planar image. However, to obtain the best performance, it should be considered certain criterion on the calculation of weights for the fuzzy weighted mean method. Therefore, a new method to calculate weights using means by differences of feature values and their variances with the maximum distance from differences of feature values. is developed. In the experiments, the recognition results with fifteen dimensional bispectral feature vectors, which are extracted from 11.808 aircraft images based on eight different styles of reference images, are compared and analyzed.

• 전자공학회논문지B
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• 제31B권9호
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• pp.142-149
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• 1994

Hangul is expressed by the basic elements, twenty-four characters. Because these characters are composed of a circle and lines, Hough transform(HT), which has a powerful performance on the noise in extracting lines, is introduced. Many difficulties often occur when the original HT is used to extract strokes and it's direction, position and length from handwritten Hangul characters. Original HT has eight direction selected as samples in the transformed image should be calculated for these eight directions. In this paper, the generalized sampling rule is suggested. According to the rule, those directions which are possible to a line are the only thing to be calculated. The experoment result turned out to be higher than the method that Chen suggested in sampling rate. Anogher experiment result is done on the 1800 handwritten Hangul characters that 10 persons wrote. By feature extracting the oritinal HT and sampling HT. And as a result of six type classification, the suggested method came out higher than original HT.

• 인터넷정보학회논문지
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• 제21권4호
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• pp.127-135
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• 2020

The purpose of this study is to develop a human activity recognition (HAR) system, which distinguishes 13 activities, including five activities commonly dealt with in conventional HAR researches and eight activities from the Eastern-Asian culture. The eight special activities include floor-sitting/standing, chair-sitting/standing, floor-lying/up, and bed-lying/up. We used a 3-axis accelerometer sensor on the wrist for data collection and designed a machine learning model for the activity classification. Data clustering through preprocessing and feature extraction/reduction is performed. We then tested six machine learning algorithms for recognition accuracy comparison. As a result, we have achieved an average accuracy of 99.7% for the 13 activities. This result is far better than the average accuracy of current HAR researches based on a smartwatch (89.4%). The superiority of the HAR system developed in this study is proven because we have achieved 98.7% accuracy with publically available 'pamap2' dataset of 12 activities, whose conventionally met the best accuracy is 96.6%.

• 한국인터넷방송통신학회논문지
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• 제19권5호
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• pp.251-255
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• 2019

프로토콜 reverse-engineering 기술은 unknown protocol 의 스펙을 추출하기 위해서 보통 표준화된 방법이 없어서 대부분 수동으로 스펙을 분석하거나 반자동 방식으로 이를 분석한다. 만약 unknown protocol의 근간이 되는 프로토콜을 알 수 있다면, 이를 이용하여 스펙을 분석할 수 있으므로 자동화되고 정확한 분석이 가능할 것이다. 학습되지 않은 프로토콜을 분류하기 위해서는 특징추출은 매우 중요한 단계 중의 하나이다. 본 논문은 기존 프로토콜을 변형한 프로토콜에 대해서 높은 성능을 갖는 분류기를 개발하기 위해서 몇 가지 특징 추출 알고리즘을 제안하고, 프로토콜의 형태 변화에 강인한 특징추출 알고리즘을 제안한다. 성능 검증을 위해서 8개 공개 프로토콜을 대상으로 학습을 수행하고 이를 변형한 프로토콜을 대상으로 성능 측정을 진행하였다.