• 한국전자파학회논문지
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• 제26권7호
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• pp.656-665
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• 2015

본 논문에서는 시간-주파수 변환에 요동보상을 적용한 UWB 레이다 Bistatic ISAR (Bistatic Inverse Synthetic Aperture Radar: B-ISAR) 이미징에 적용하여 레이다 이미징의 선명도와 품질을 개선하였다. UWB 레이다를 사용하여 제안하는 시간-주파수 알고리즘을 검증하였으며, 이를 위하여 B-ISAR 알고리즘 절차, 시간-주파수 변환과 요동보상 개선 등 필요한 이론적 근거를 제시하였다. B-ISAR 이미징 알고리즘으로 이미지를 생성하였으며, UWB 바이스테틱 ISAR 이미징 생성시 요동보상을 적용한 시간-주파수 변환 기법인 STFT(Short-Time Fourier Transform), GWT(Gabor Wavelet Transform), WVD(Wigner-Ville distribution) 방식을 차례대로 구현하였다. 그리고 STFT, GWT와 WVD 알고리즘을 이용하여 B-ISAR 이미징 알고리즘의 성능을 비교하였으며, 그 결과 WVD가 다른 방식들에 비하여 영상이 선명하고, 퍼짐 현상이 줄어듦을 알 수 있었다.

• 스마트미디어저널
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• 제11권7호
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• pp.61-69
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• 2022

학습된 머신러닝은 시간 경과에 따른 학습 모델과 학습 데이터 측면의 표류 현상이 발생과 동시에 머신러닝의 성능이 퇴화하게 된다. 이를 해결하기 위한 방안으로 머신러닝의 재학습 시기를 결정하기 위한 ML 표류의 개념과 평가 방법을 제안하고자 한다. 딸기와 선명도에 따른 XAI 테스트 및 사과 이미지의 XAI 테스트를 진행하였다. 딸기의 경우 선명도 값에 따른 ML 모델의 XAI 분석의 변화는 미미하였으며 사과 이미지의 XAI의 경우 사과는 정상적으로 객체 분류 및 히트맵 영역을 표시하였으나 사과꽃 및 꽃봉오리의 경우 그 결과가 딸기나 사과에 비해 미미하였다. 이는 사과꽃 및 꽃봉오리의 학습 이미지 수가 부족하기에 발생한 것으로 예상되며 추후 더 많은 사과꽃 및 꽃봉오리 이미지를 학습하여 테스트할 계획이다.

• 한국해양공학회지
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• 제36권1호
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• pp.32-40
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• 2022

Underwater optical images face various limitations that degrade the image quality compared with optical images taken in our atmosphere. Attenuation according to the wavelength of light and reflection by very small floating objects cause low contrast, blurry clarity, and color degradation in underwater images. We constructed an image data of the Korean sea and enhanced it by learning the characteristics of underwater images using the deep learning techniques of CycleGAN (cycle-consistent adversarial network), UGAN (underwater GAN), FUnIE-GAN (fast underwater image enhancement GAN). In addition, the underwater optical image was enhanced using the image processing technique of Image Fusion. For a quantitative performance comparison, UIQM (underwater image quality measure), which evaluates the performance of the enhancement in terms of colorfulness, sharpness, and contrast, and UCIQE (underwater color image quality evaluation), which evaluates the performance in terms of chroma, luminance, and saturation were calculated. For 100 underwater images taken in Korean seas, the average UIQMs of CycleGAN, UGAN, and FUnIE-GAN were 3.91, 3.42, and 2.66, respectively, and the average UCIQEs were measured to be 29.9, 26.77, and 22.88, respectively. The average UIQM and UCIQE of Image Fusion were 3.63 and 23.59, respectively. CycleGAN and UGAN qualitatively and quantitatively improved the image quality in various underwater environments, and FUnIE-GAN had performance differences depending on the underwater environment. Image Fusion showed good performance in terms of color correction and sharpness enhancement. It is expected that this method can be used for monitoring underwater works and the autonomous operation of unmanned vehicles by improving the visibility of underwater situations more accurately.

• 디자인학연구
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• 제17권1호
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• pp.329-338
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• 2004

본 연구는 문헌연구를 바탕으로 표지디자인의 개념 및 기능, 구성요소를 고찰하고 1999년부터 2002년까지 문학부문 베스트셀러 표지디자인의 사례분석을 통해 표지디자인의 특징을 도출하였다. 독자의 연령과 성별에 따라 표지디자인에 대한 독자의 선호도를 설문조사와 이미지 평가를 통해 책표지 디자인의 조건 및 방법을 제안하고자 하였다. 표지디자인의 선호도 조사에서 연령, 성별에 따라 관심있게 읽는 책의 종류와 책을 구매하는 장소, 표지디자인에 대한 관심도에 차이가 있었다. 또한 여자는 스타일서체를 선호하며, 남녀 모두 한색을 선호하는 것으로 나타났다. 하지만 그 외의 시각적 요소에대한 선호도 차이가 없는 것은 표지디자인이 여러 요소들로 이루어진 통합적인 이미지이기 때문이다. 그리하여 SD법을 통해 통합적인 이미지로써 표지디자인에 대한 평가를 실시하였다. 그 결과 지나친 추상적 이미지는 명료성이 떨어져 의미전달이 어려운 것으로 나타났다. 또한 스타일 서체가 주를 이룬 표지디자인이 독특성, 명확성에서 높은 평가를 받았다. 비주얼이 뛰어나다고 해도 기능적인 면인 의미전달에서 뛰어난 것과는 차이가 있었다. 이 논문은 시각적 요소만을 한정하여 살펴보았다. 향후 표지디자인을 구성하고 있는 요소들인 재료, 재본, 형태 등에 따라 독자의 선호에 미치는 영향에 대한 연구가 진행되어야 할 것이다.

• Journal of information and communication convergence engineering
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• 제7권4호
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• pp.442-448
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• 2009

This paper proposes a fingerprint image processing algorithm to accurately extract minutiae in the process of fingerprint recognition. We improved the matching accuracy of low quality fingerprint images by using effective ridge vector and ridge probability. The proposed algorithm improves the clarity of ridge structures and reduces undesired noise. We collected thumb print images from 10 individuals 5 separate times each, in total using 50 thumbprints. We registered one of the five thumbprint images from each individual to match the registered one with the other four thumbprint images, and alternated the registered thumbprint image. We matched thumbprints 20 times for each individual. In total, we conducted 200 matches for the thumbprints from the 10 individuals. We improved the verification accuracy and reliability compared to conventional methods.

• 치과방사선
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• 제19권1호
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• pp.25-29
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• 1989

The author has evaluated the panoramic image clarity of the midfacial anatomic structures in dry skull according to the skull position. The radiopaque markers were attached to the anatomic structures: infraorbial rim, upper and lower borders of zygomatic arch, pterygomaxillary fissure, lateral pterygoid plate, pyriform aperture of nasal cavity, lateral wall of maxilla, orbital floor, infraorbital foramen, and nasal floor. Position of the skull were divided into four groups. standard, 25mm forward, chin-down, chin-up position. The results were as follows: 1. The pyriform aperture of nasal cavity, lateral wall of the maxilla, orbital floor, infraorbital foramen and nasal floor did net cast any discernible image. 2. Nearly all images of midfacial structures were blurred in the chin-up position. 3. The forward position provided good visualization of the maxillary sinus. 4. The chin-down position provided good visualization of the zygomatic arch, pterygomaxillary fissue, and lateral pterygoid plate.

• Industrial Engineering and Management Systems
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• 제9권1호
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• pp.20-27
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• 2010

The purpose of this study was to compare the consistency of external ear measurements obtained by electronic digital caliper, photocopier scanning and digital photographic methods. Photogrammetric measurements were made after image editing software was used to optimize the brightness, contrast, size and image clarity. The CorelDRAW dimension tool was used to create a dimension line that measured the vertical and horizontal length between any two landmarks. Results of repeated measures analysis of variance revealed no significant differences in length and width of the pinna between the three methods. The reliability of the three measurement techniques showed a high degree of consistency. Further study and efforts could be extended to measurement hands, foots and facial dimensions by present techniques.

• 한국의상디자인학회지
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• 제14권2호
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• pp.11-21
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• 2012

The purpose of this study is to understand of future image in fashion for 20C, to suggest a guideline's role in the development on fashion designs study. The methods of this study are used academic literatures as well as practical study. Futuristic image in fashion is to introduce about the future period, as fashion goes ahead times. Trends and formative characteristics of future image in 20C fashion are summarized as follows. First, futuristic images in fashion for 20C had emerged strongly futurism, space look, kinetic look, glitter look, techno look, cyber look. Second, perspectives on response for future society's changes are summarized as follows. Attitude of futuristic images of fashion, futurism, space look, kinetic look and glitter look, had been favorable about future society's changes until 1980. In 1990, techno look had been defensive and cyber look had been aggressive about future society's changes. Third, formative characteristics of future image in 20C fashion are studied shape, material, color, pattern. Shape was preferred linear and geometric form in the first half of the 20C, but body conscious type had appeared often in the second half of 20C. Material maintained the luster or the metal touch. Color was based image of colorless and preferred the gold, silver or color feels like metal. Pattern was preferred clarity with geometric type in the first half of the 20C. On the other hand in the second half of 20C pattern of future image was dominated by vague and abstract chaotic type.

• Computers and Concrete
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• 제19권2호
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• pp.203-210
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• 2017

The purpose of this paper is to evaluate the settlement of lightweight coarse aggregate of self-compacting lightweight concrete (SCLC) after placement of concrete on its final position. To investigate this issue, sixteen samples of concrete mixes were made. The water to cementitious materials ratios of the mixes were 0.35 and 0.4. In addition to the workability tests of self-compacting concrete (SCC) such as slump flow, V-funnel and L-box tests, a laboratory experiment was made to examine the segregation of lightweight coarse aggregate in concrete. Because of the difficulties of this test, the image processing technique of MATLAB software was used to check the segregation above too. Moreover, the fuzzy logic technique of MATLAB software was utilized to improve the clarity of the borders between the coarse aggregate and the paste of the mixtures. At the end, the results of segregation tests and software analyses are given and the accuracy of the software analyses is evaluated. It is worth noting that the minimum and maximum differences between the results of laboratory tests and software analyses were 1.2% and 9.19% respectively. It means, the results of image processing technique looks exact enough for estimating the segregation of lightweight coarse aggregate in SCLC.

• 한국정보처리학회논문지
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• 제4권10호
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• pp.2553-2561
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• 1997

본 논문에서는 영상인식을 위한 직선 HT(Hough transform) 알고리즘 연산의 하드웨어 구조를 제안하였다. 이 연산기는 기울기연산을 위한 필터링부위와 HT 연산부위로 이루어졌으며, 이때 각도에 관한 정보는 메모리 테이블에 저장하였다. 제안된 구조는 C 언어를 이용한 알고리즘 시뮬레이션을 수행하며 동작의 확인과 계산의 정밀도를 결정한 다음, 전체블록에 대하여 VHDL 언어에 의한 아키텍쳐 시뮬레이션을 수행하였다. 각 실험결과에 의하면, 연산된 데이타 값이 유사하게 얻어졌으며, 영상의 선명도와 사용 비트수가 커질수록 연산값의 차이가 적어짐을 확인하였다.