• 한국콘텐츠학회논문지
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• 제1권1호
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• pp.74-82
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• 2001

시각암호는 정보보호 분야에서 중요한 정보를 암호화하여 복수 회원에게 분산시킨 후 회원의 합의에 의하여 해독이 가능하게 하는 thresholding scheme을 디지털 시스템인 아닌 인간의 시각 시스템으로 복호가 가능하게 하였다. 그러나 이러한 방법은 표현의 한계로 인하여 몇 가지 문제점을 안고 있었다. 이후 인간의 시각을 대신하여 레이저를 사용하는 광시각암호가 제안되어 광학 시스템에 암호 기법을 적용할 수 있게 되었다. 그러나 이 시스템은 기존의 시각 암호의 문제점을 완전히 극복하지 못함으로 인하여 또 다른 문제를 발생하였다. 이것은 데이터 처리 시스템을 시각에서 광학으로 전환하는 과정에서 발생하기 때문에 문제의 분석과 해결 역시 광학적으로 접근하는 것이 타당하다. 본 논문에서는 상관기를 이용하여 광시각 암호의 처리에서 발생하는 잡음의 정도와 암호 특성을 주파수 관점에서 분석한다.

• 디자인학연구
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• 제21권
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• pp.77-86
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• 1997

현대사회는 매스미디어에 의한 이미지의 시대이다. 광고매체는 이러한 현대사회의 일상생활에서의 각종 시각정보전달 매체 물을 통한 수용자의 이미지의 접촉과 반도에 지대한 자극과 영향을 준다. 신문, 잡지광고 텍스트 제작에 있어서 서체(typeface)선택의 활용에 따른 시각이미지(시심상, visual image)의 비교 연구를 통하여 볼 때, 헤드라인 서체의 선택은 광고카피의 중요성 못지 않게, 광고 컨셉에 맞는 발신자(광고주, client)와 수용자(소비자, consumer)의 관계에서 보다 효율적인 대 소비자를 향한 광고효과의 증대를 위해 중시되어져야 한다. 한편 이러한 헤드라인 서체의 시각이미지(시심상, visual image)는 다른 시각화상정보 전달요소(그림, 시진 등)들과 '심리적 조화의 일치' 라는 관점에서 행하여져야 한다. 이는 모든 인간들이 각자의 얼굴을 지니고, 각기 맡은바 역할에 맞추어 살아가는 것과 같이, 서체(typeface)도 각기 서체가 갖는 이미지의 '심리적 조화의 일치'하에 활용될 때 서체의 개성과 역할이 배가되어지기 때문이다.

• 식물분류학회지
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• 제47권2호
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• pp.124-131
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• 2017

Species identification is a fundamental and routine process in plant systematics, and linguistic-based dichotomous keys are widely used in the identification process. Recently, novel tools for species identification have been developed to improve the accuracy, ease to use, and accessibility related to these tasks for a broad range of users given the advances in information and communications technology. A visual identification key is such an approach, in which couplets consist of images of plants or a part of a plant instead of botanical terminology. We developed a visual identification key for 101 taxa of Orchidaceae in Korea and evaluated its performance. It uses short statements for image couplets to avoid misinterpretations by users. The key at the initial steps (couplets) uses relatively easy characters that can be determined with the naked eye. The final steps of the visual key provide images of species and information about distributions and flowering times to determine the species that best fit the available information. The number of steps required to identify a species varies, ranging from three to ten with an average of 4.5. A performance test with senior college students showed that species were accurately identified using the visual key at a rate significantly higher than when using a linguistic-based dichotomous key and a color manual. The findings presented here suggest that the proposed visual identification key is a useful tool for the teaching of biodiversity at schools, for the monitoring of ecosystems by citizens, and in other areas that require rapid, easy, and accurate identifications of species.

• 대한원격탐사학회지
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• 제17권4호
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• pp.319-334
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• 2001

Extracting primitives from imagery plays an important task in visual information processing since the primitives provide useful information about characteristics of the objects and patterns. The human visual system utilizes features without difficulty for image interpretation, scene analysis and object recognition. However, to extract and to analyze feature are difficult processing. The ultimate goal of digital image processing is to extract information and reconstruct objects automatically. The objective of this study is to develop robust method to achieve the goal of the image processing. In this study, an adaptive strategy was developed by implementing Gabor filters in order to extract feature information and to segment images. The Gabor filters are conceived as hypothetical structures of the retinal receptive fields in human vision system. Therefore, to develop a method which resembles the performance of human visual perception is possible using the Gabor filters. A method to compute appropriate parameters of the Gabor filters without human visual inspection is proposed. The entire framework is based on the theory of human visual perception. Digital images were used to evaluate the performance of the proposed strategy. The results show that the proposed adaptive approach improves performance of the Gabor filters for feature extraction and segmentation.

• 한국조경학회지
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• 제26권2호
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• pp.269-282
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• 1998

The visual preference of interiors focusing on lobbies was investigated as a function of six predictor variable on the base of the Informational Approach: complexity, coherence, mystery, spaciousness, brightness, plant. The Common Fcator Analysis of preference ratings yielded six common factors which helped to account for 22.3 percent of the variance in preference response to the scene. Among these factors, the factor defined as 'bright with many plants' was the most preferred and the factor defined as 'simple and closed' was the least preferred. The environmental attributes reflected in six groups of scenes were colour, resting place, window and the six predictors. In the commercial building scenes, complexity, spaciousness, coherence, brightness and mystery out of six predictors accounted for 74 percent of preference variance as the significant contributors. In the business building scenes, three predictors which are brightness, complexity, spaciousness accounted for 84 percent of preference variance. 'The amount of plant' not only influenced the preference indirectly through the intervening variable, complexity, but also was moderately correlated with brightness. The overall pattern of the resulted confirmed the usefulness of the Informational Approach to predict the preference in interiors focusing on lobbies.

• Journal of Information Processing Systems
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• 제16권5호
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• pp.1183-1195
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• 2020

Visual saliency detection is an essential task because it is an important part of various vision-based applications. There are many techniques for saliency detection in color images. However, the number of methods for saliency detection in infrared images is limited. In this paper, we introduce a simple approach for saliency detection in infrared images based on the thresholding technique. The input image is thresholded into several Boolean maps, and an initial saliency map is calculated as a weighted sum of the created Boolean maps. The initial map is further refined by using thresholding, morphology operation, and a Gaussian filter to produce the final, high-quality saliency map. The experiment showed that the proposed method has high performance when applied to real-life data.

• Current Optics and Photonics
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• 제4권3호
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• pp.200-209
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• 2020

We describe an approach that uses a bilateral filter to reduce the ringing artifact in motion-blurred restoration image. It takes into account the specific physical structure of the ringing artifact combined with the properties of the human visual system. To properly reduce the ringing artifact, each of the adjacent pixels is limited in a straight line which has a given direction. To protect the edges and the texture regions of an image, our algorithm divides the image into texture regions and flat regions, and the artifact reduction algorithm is only applied to the flat region. Finally, we use 8 typical images and 5 objective quality evaluation indices to evaluate our algorithm. Experimental results show that our algorithm can obtain better results in subjective visual effect and in objective image quality evaluation.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제14권1호
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• pp.8-16
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• 2014

We consider the visual barcode recognition problem in a noisy video data setup. Unlike most existing single-frame recognizers that require considerable user effort to acquire clean, motionless and blur-free barcode signals, we eliminate such extra human efforts by proposing a robust video-based barcode recognition algorithm. We deal with a sequence of noisy blurred barcode image frames by posing it as an online filtering problem. In the proposed dynamic recognition model, at each frame we infer the blur level of the frame as well as the digit class label. In contrast to a frame-by-frame based approach with heuristic majority voting scheme, the class labels and frame-wise noise levels are propagated along the frame sequences in our model, and hence we exploit all cues from noisy frames that are potentially useful for predicting the barcode label in a probabilistically reasonable sense. We also suggest a visual barcode tracking approach that efficiently localizes barcode areas in video frames. The effectiveness of the proposed approaches is demonstrated empirically on both synthetic and real data setup.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -2
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• pp.851-854
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• 2000

Digital halftoning is a technique to make an equivalent binary image from scanned photo or graphic images. Low pass filtering characteristic of human visual system can be applied to get the effect of spatial averaging of local area consisted of black and white pixels for gray image. The overlapping of black dot decreases brightness and black dot is very sensitive to human visual system in the bright region. In this paper, for gray-level expression, only bright gray region in the color image is considered for blue noise mask (BNM) approach. To solve this problem, BNM with CMY dot is used for the bright region instead of black dot. Dot-on-dot model with single mask causes the problem making much black dot overlap, color distortion. Therefore approach with three masks for C, M and Y each is proposed to decrease pixel overlap and color distortion.

• Journal of Korean Neurosurgical Society
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• 제45권6호
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• pp.375-377
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• 2009

A 49-year-old woman presented with headache, vomiting and visual disturbance. Neurological examination revealed bitemporal hemianopsia with poor visual acuity. Magnetic resonance imaging showed a bulky intra-suprasellar mass, which was isointense with brain parenchyma on T1-weighted images, and slightly hyperintense on T2-weighted images. After gadolinium administration, the mass was homogeneously enhanced. The mass was partially removed by the endonasal transsphenoidal approach and then the remnant mass was totally removed by the transcranial approach five months later. We found a yellowish mass which was attached to the diaphragm sellae in operation field. Histopathological examination of the tumor revealed the characteristic features of a schwannoma. We report an unusual case of an intra-suprasellar schwannoma resembling a non-functioning pituitary macroadenoma both clinically and radiologically.