• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권9호
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• pp.3672-3684
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• 2015

Recently, the standardization of backward compatible JPEG image coding for high dynamic range (HDR) image has been undertaken to establish an international standard called "JPEG XT." The JPEG XT consists of two layers: the base layer and the residual layer. The base layer contains tone mapped low dynamic range (LDR) image data and the residual layer contains the error signal used to reconstruct the HDR image. This paper gives the result of a study to evaluate the overall performance of tone mapping operators (TMOs) for this standard. The evaluation is performed using five HDR image datasets and six TMOs for profiles A, B, and C of the proposed JPEG XT standard. The Tone Mapped image Quality Index (TMQI) and no reference image quality assessment (NR IQA) are used for measuring the LDR image quality. The peak signal to noise ratio (PSNR) is used to evaluate the overall compression performance of JPEG XT profiles A, B, and C. In TMQI and NR IQA measurements, TMOs using display adaptive tone mapping and adaptive logarithmic mapping each gave good results. A TMO using adaptive logarithmic mapping gave good PSNRs.

• 방송공학회논문지
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• 제21권6호
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• pp.920-928
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• 2016

최근 넓은 동적 영역 이미지 기술은 컴퓨터 그래픽 분야에서 화제다. 본 논문에서는 가중 최소자승(가중회귀분석) 최적화 체계에 기반하여 넓은 동적 영역 이미지를 처리하는 톤매핑 알고리듬을 제안한다. 제안하는 방법은 시각적 후광 현상을 피하는 동시에 기존의 디스플레이에서 더 지각적인 넓은 동적 영역 이미지들을 보여주기 위해 가중 최소자승 필터링과 iCAM06모델을 결합한다. 제안된 알고리듬은 먼저 넓은 동적 영역 이미지를 base layer와 detail layer로 나눈다. Base layer는 큰 규모의 변화량을 가지고 있으며 가중 최소자승 필터링을 사용하여 얻어지고 iCAM06 모델을 포함한다. 다음으로, 인간의 시각 체계에 따라 base layer는 적응적으로 압축된다. 압축 시에는 base layer만 대비를 줄이고 detail layer을 보존한다. 본 논문에서는 객관적 화질 평가와 주관적 화질 평가를 통하여 제안하는 알고리듬을 적용한 이미지가 기존의 알고리듬을 적용한 이미지들에 비해 원본 넓은 동적 영역 이미지에 더 유사하다는 것을 보여준다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권4호
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• pp.1846-1863
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• 2016

High dynamic range (HDR) images can present the perfect real scene and rich color information. A commonly encountered problem in practical applications is how to well visualize HDR images on standard display devices. In this paper, we propose a multi-scale decomposition method using guided filtering for HDR image tone mapping. In our algorithm, HDR images are directly decomposed into three layers：base layer, coarse scale detail layer and fine detail layer. We propose an effective function to compress the base layer and the coarse scale detail layer. An adaptive function is also proposed for detail adjustment. Experimental results show that the proposed algorithm effectively accomplishes dynamic range compression and maintains good global contrast as well as local contrast. It also presents more image details and keeps high color saturation.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.575-578
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• 1999

The principal features of a face are as follows : skin-tone, symmetry, and requisites such as shape of ellipse, eyes, nose, mouth. Also, faces have different size, various shape and position. In case of application of face recognition and detection without preprocessing, efficiency of the performance is decreased. In addition, face itself, complex background, image quality, etc. are included. Therefore, previous face recognition methods are implemented on the base of specific constraints of the face image. In this paper, we propose the efficient and automatic face detection algorithm for minimizing influence such as complex background, image quality, etc. This face detection technique consists of skin-tone, candidate face region and face region extractions.

• 한국의류산업학회지
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• 제13권3호
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• pp.332-345
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• 2011

This research designed usable standard color chart which was planned by hue and tone color system. This research studied 5 types standard color chart by designed tone map and preceding research. "Basic Color Chart 14 Colors" was planned for kindergarteners. "Primary Color Chart 63 Colors" was planned for schoolboys. "Middle Grade Color Chart 114 Colors" was planned for junior high school students. "High Grade Color Chart 152 Colors" was planned for senior high school students. "Hue and Tone 205 Colors" was planned for university students and general publics. These 5 types standard color chart were produced the trial color coordinate card and attached the Munsell notation which could reappear the spare color paper when needed. These 5 types standard color chart would be offered the data base for efficient color coordinate education as school age.

• 한국멀티미디어학회논문지
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• 제19권5호
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• pp.837-847
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• 2016

Tone mapping for High Dynamic Range(HDR) image provides matching human visual perception between real world scene and displayable devices. Recently, a tone mapping algorithm based on localized gamma correction is proposed. This algorithm is using human visual properties of contrast and colorfulness with background intensity, generating a weight map for gamma correction. However, this method have limitations of controlling enhancement region as well as generating halo artifacts caused by the weight map construction. To overcome aforementioned limitations, proposed algorithm in this paper modifies previous weight map, considering base layer intensity of input luminance channel. By determining enhancement region locally and globally based on base layer intensity, gamma values are corrected accordingly. Therefore, proposed algorithm selectively enhances local brightness and controls strength of edges. Subjective evaluation using z-score shows that our proposed algorithm outperforms the conventional methods.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2011년도 춘계학술대회
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• pp.617-618
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• 2011

인간은 누구나 좋아하는 색이 자연적으로 혹은 인위적으로 존재한다. 본 논문에서는 인간에게 어울리는 색을 찾는 방법에 대하여 제시하고자 한다. 우선, 피부의 색, 머리카락의 색, 눈동자의 색과 같이 색의 기본을 이루는 톤에 대하여 알아본다. 다음으로 색을 봄, 여름, 가을, 겨울의 사계절로 나누어 피부의 색, 머리카락의 색, 눈동자의 색과 본인이 좋아하는 것이나 성격에 따라서 나누어지는 사계절 색채이론을 설명한다. 그리고 각 계절별 컬러의 특성을 살펴 보도록 한다.

• 대한물리의학회지
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• 제2권2호
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• pp.243-250
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• 2007

Purpose : Shoulder subluxation is a very common problem in patients with hemiplegia with stroke. Prevention of the low tone subluxed shoulder has been an issue for physical therapists working with neurological patients for many years. Methods : This study reviewed the literature to definite the management and a cause of shoulder subluxation with hemiplegia patients after stroke. Various modalities have been suggested for realigning the glenohumeral joint, but their use is controversial. The purpose of this paper is to review critically the evidence base in order to inform the clinical decision-making process for physiotherapists working in neurology. Results : Literature has identified supports, strapping and functional electrical stimulation(FES) in the management of low tone shoulders. Following review of this evidence it is suggested that there is a lack of reliable and valid research evidence on which to base conclusions. The modalities with the best supporting evidence for realigning the low tone subluxed glenohumeral joint are the triangular sling, Harris hemi sling and the Rolyan humeral cuff used in a standing position and the lap board and arm trough while the patient is sitting. However, due to soft tissue adaptation with associated lack of movement, over-correction and the need for careful patient positioning these supports need to be evaluated for each patient and should be used only in appropriate situations. Conclusion : Similarly, there is a lack of evidence on the effects of long-term use to this equipment. Electrical stimulation is also thought to have potential in the treatment to subluxed low tone shoulders but additional research is required to clarify the parameters for use and the long-term effects of these forms of management.

• 한국농촌건축학회논문집
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• 제13권4호
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• pp.51-58
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• 2011

The purpose of this study was analyzing the features of architectural colors in Hongseong-gun and proposing environmental color design for regional identity color. According to the analysis, Hongseong's base colors are YR of low hue value and grayish tone colors. But a lot of signs and outdoor billboards mar the beauty of the environmental color. So it is more important to solve the problems as well as new environmental color design. The results are as follows; 1) Naepo Color Palette of 2009 Chungnam Public Design Master Plan would be an accepted principal for the contextual landscape image of Chungnam in macro perspective. 2) Outdoor signboards must be controlled and improved for the harmony of the buildings dominant colors. 3) Roof color would arrange R or grayish of deep tone colors those are similar balance of Hongseong base color YR, and gate color would have clear principles of the order such as chromatic or brightness contrast in housing. 4) Forming of future oriented image of Hongseong need to be considered first as to whether it is harmonious tones with existing local base colors.

• 한국가시화정보학회지
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• 제9권4호
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• pp.35-40
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• 2011

An experimental investigation of the characteristic of non-premixed lifted flames with nozzle hole-tone of high-frequency has been performed. Before the fuel was supplied to nozzle, the fuel was supplied through a burner cavity which was located under the nozzle. The fuel passed through the excitation cavity under the influence of the high-frequency affects the lifted flame characteristics. The measurements were performed in flow range that occurs lifted flame and blow out. When the high-frequency is generated from burner cavity, the lifted length became shorter, and noise reduced comparing to unexcitation case. Additionally, operating flow range was increased and diameter of flame base became smaller with high-frequency effect. Through this experiments, it's ascertained that the high-frequency excitation can be adopted with effective method for flame stability and noise reduction.