• Title/Summary/Keyword: contrast transformation

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A Study on the Color Reproduction Characteristic of Original Copy in Display Device (디스플레이 장치에서 인쇄원고의 컬러 재현특성에 관한 연구)

  • Cho, Ga-Ram;Koo, Chul-Whoi
    • Journal of the Korean Graphic Arts Communication Society
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    • v.23 no.1
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    • pp.65-75
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    • 2005
  • An accurate characterization of the display device is essential for better color matching. The calibration and characterization process in display device is needed to transform the device dependent color to the device independent color. The process of characterization performs a linearization and transforms the linearized values into the CIE XYZ tristimulus values. The purposes of this paper is to propose optimal color transformation method for accurate reproduction of original copy in display device and to explain the propriety of transformation method using specific variable for the power of gradation expression.

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Weighted Histogram Equalization Method adopting Weber-Fechner's Law for Image Enhancement (이미지 화질개선을 위한 Weber-Fechner 법칙을 적용한 가중 히스토그램 균등화 기법)

  • Kim, Donghyung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.7
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    • pp.4475-4481
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    • 2014
  • A histogram equalization method have been used traditionally for the image enhancement of low quality images. This uses the transformation function, which is a cumulative density function of an input image, and it has mathematically maximum entropy. This method, however, may yield whitening artifacts. This paper proposes the weighted histogram equalization method based on histogram equalization. It has Weber-Fechner's law for a human's vision characteristics, and a dynamic range modification to solve the problem of some methods, which yield a transformation function, regardless of the input image. Finally, the proposed transformation function was calculated using the weighted average of Weber-Fechner and the histogram equalization transformation functions in a modified dynamic range. The simulation results showed that the proposed algorithm effectively enhances the contrast in terms of the subjective quality. In addition, the proposed method has similar or higher entropy than the other conventional approaches.

Java Memory Model Simulation using SMT Solver (SMT 해결기를 이용한 자바 메모리 모델 시뮬레이션)

  • Lee, Tae-Hoon;Kwon, Gi-Hwon
    • Journal of KIISE:Computing Practices and Letters
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    • v.15 no.1
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    • pp.62-66
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    • 2009
  • Recently developed compilers perform some optimizations in order to speed up the execution time of source program. These optimizations require the transformation of the sequence of program statements. This transformation does not give any problems in a single-threaded program. However, the transformation gives some significant errors in a multi-threaded program. State-of-the-art model checkers such as Java-Pathfinder do not consider the transformation resulted in the optimization step in a compiler since they just consider a single memory model. In this paper, we describe a new technique which is based on SMT solver. The Java Memory Model Simulator based on SMT Solver can compute all possible output of given multi-thread program within one second which, in contrast, Traditional Java Memory Model Simulator takes one minute.

Chloroplast Genetic Transformation in Higher Plants: An Encounter Between Prokaryote and Eukaryote (고등식물의 엽록체 형질전환: 원핵생물과 진맥생물의 조우)

  • Chung, Hwa-Jee;Suh, Young-Bae;Jeong, Won-Joong;Min, Sung-Ran;Liu, Jang-R.
    • Journal of Plant Biotechnology
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    • v.33 no.3
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    • pp.185-194
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    • 2006
  • Chloroplasts are believed to be descended from certain cyanobacteria, which were taken up by phagocytosis into a host cell and lived there in a symbiotic relationship. In contrast to the current static concept on the chloroplast genome, its dynamism has been recently demonstrated: the chloroplast genome is active in intramolecular homolgous recombination, producing subgenomic circles when it obtains homolgous sequences via genetic transformation. Chloroplast tranformation in higher plants provides many advantages over nuclear transformation that include higher expression levels of transgenes, polycistronic expression of transgenes, and maternal transmission of transgenes. Tobacco has been used as a model for chloroplast genetic transformation. However, it is recently possible to transform the chloroplasts of other major food and economic crops including rice, soybean, and cotton. Chloroplast-transformed crops will be able to replace bioreactors using microorganisms for production of value-added proteins in future.

Multi GPU Based Image Registration for Cerebrovascular Extraction and Interactive Visualization (뇌혈관 추출과 대화형 가시화를 위한 다중 GPU기반 영상정합)

  • Park, Seong-Jin;Shin, Yeong-Gil
    • Journal of KIISE:Computing Practices and Letters
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    • v.15 no.6
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    • pp.445-449
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    • 2009
  • In this paper, we propose a computationally efficient multi GPU accelerated image registration technique to correct the motion difference between the pre-contrast CT image and post-contrast CTA image. Our method consists of two steps: multi GPU based image registration and a cerebrovascular visualization. At first, it computes a similarity measure considering the parallelism between both GPUs as well as the parallelism inside GPU for performing the voxel-based registration. Then, it subtracts a CT image transformed by optimal transformation matrix from CTA image, and visualizes the subtracted volume using GPU based volume rendering technique. In this paper, we compare our proposed method with existing methods using 5 pairs of pre-contrast brain CT image and post-contrast brain CTA image in order to prove the superiority of our method in regard to visual quality and computational time. Experimental results show that our method well visualizes a brain vessel, so it well diagnose a vessel disease. Our multi GPU based approach is 11.6 times faster than CPU based approach and 1.4 times faster than single GPU based approach for total processing.

The Comparative Study of the Harmony of Coloration according to Transformation of Color Area-Ratio in Traditional Korean Dress of Korean and American Students - On the similarity and contrast coloration - (치마$\cdot$저고리의 색상 면적비 변화에 따른 한$\cdot$미 여대생의 조화감 비교 연구 - 유사배색과 대비배색을 중심으로 -)

  • Kang Kyung-Ja;Moon Ju-young;Lim Ji-Young
    • Journal of the Korea Fashion and Costume Design Association
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    • v.7 no.3
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    • pp.17-26
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    • 2005
  • In this research, in order to find out the effect of the area ratio in the harmonic sense assessment of the coloration of Korean clothes, the coloration of a Korean jacket and a skirt was compounded with a similar coloration and a contrast coloration. The respondents were asked to evaluate 16 stimuli of the traditional Korean skirt and jacket with the coloration of the Korean jacket/ skirt, the skirt/ Korean jacket was separately compounded to be 4 tones such as vivid, light, dull, dark. The subjects were 44 female undergraduate students. The results of each can be summerized as follows. As to similar coloration, the korean yellow jacket and red skirt, Korean students feel vivid and dull tone was harmonious, and American students feel vivid, light, and dark tone were harmonious coloration. In inversed case, red korean jacket and yellow skirt, both countries' students recognized that the vivid tone was harmonious. Korean students gave higher points to korean traditional dress in similar coloration such as yellow korean jacket which was small area and red skirt which was large area coloration than inversed color area ratio which red korean jacket and yellow skirt. As to contrast coloration, the korean green jacket and red skirt, Korean students feel vivid tone was harmonious, and American students feel vivid, dark tone were harmonious coloration. In inversed case, red korean jacket and green skirt were recognized that any tone was not harmonious for both countries' students. Both countries of student showed the culture gap. Compared with American students, Korean students were familiar with korean dress's traditional coloration, as a result familiar coloration was recognized harmonious coloration.

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Stitching Method of Videos Recorded by Multiple Handheld Cameras (다중 사용자 촬영 영상의 영상 스티칭)

  • Billah, Meer Sadeq;Ahn, Heejune
    • Journal of Korea Society of Industrial Information Systems
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    • v.22 no.3
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    • pp.27-38
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    • 2017
  • This Paper Presents a Method for Stitching a Large Number of Images Recorded by a Large Number of Individual Users Through a Cellular Phone Camera at a Venue. In Contrast to 360 Camera Solutions that Use Existing Fixed Rigs, these Conditions must Address New Challenges Such as Time Synchronization, Repeated Transformation Matrix Calculations, and Camera Sensor Mismatch Correction. In this Paper, we Solve this Problem by Updating the Transformation Matrix Using Time Synchronization Method Using Audio, Sensor Mismatch Removal by Color Transfer Method, and Global Operation Stabilization Algorithm. Experimental Results Show that the Proposed Algorithm Shows better Performance in Terms of Computation Speed and Subjective Image Quality than that of Screen Stitching.

Malignant Transformation of an Epidermoid Cyst in the Cerebellopontine Angle

  • Chon, Kyu-Hyon;Lee, Jong-Myong;Koh, Eun-Jung;Choi, Ha-Young
    • Journal of Korean Neurosurgical Society
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    • v.52 no.2
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    • pp.148-151
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    • 2012
  • Intracranial squamous cell carcinoma is extremely rare, with most of the cases arising from malignant transformation of an epidermoid or a dermoid cyst. The patient presented with facial weakness. Initial magnetic resonance imaging revealed a mass in the right cerebellopontine angle. A subtotal resection was performed via right retrosigmoid suboccipital approach. Histopathological findings were consistent with an epidermoid tumor. Five months later, the patient underwent gamma knife radiosurgery due to highly probable recurrent epidermoid tumor. Two years after, the patient's neurological deficit had been newly developed, and follow-up magnetic resonance imaging demonstrated a large contrast-enhancing tumor in the left cerebellopontine angle, which compressed the brainstem. After resection of the tumor, histopathological examinations revealed a squamous cell carcinoma probably arising from an underlying epidermoid cyst. We report a case of an epidermoid tumor in the cerebellopontine angle that transformed into a squamous cell carcinoma.

A Study on Formation and Contents of 『Mokgwaillam』 (『목과일람(目科一覽)』의 편제(編制)와 내용(內容)에 대한 고찰(考察))

  • Song, Ji-Chung;Sim, Hyun-A;Keum, Kyung-Su;Eom, Dong-Myung
    • The Journal of Korean Medical History
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    • v.26 no.2
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    • pp.31-61
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    • 2013
  • Objective : The field of specialty in medicine origins from general or comprehensive theories of medicine. "Mokgwaillam" is a book of ophthalmology. However, its contents are from "Dongeuibogam" "Ahn" We need to compare "Mokgwaillam" with "Dongeuibogam" "Ahn" and find out how they are different or similar. Method : Contents comparison between "Mokgwaillam" and "Dongeuibogam" "Ahn" was conducted in contents movement, deletion, transformation and so on. Result : The most content of "Mokgwaillam" derived from "Dongeuibogam" "Ahn" even though "Mokgwaillam" adjusted several parts of "Dongeuibogam" "Ahn" as a book of ophthalmology. Conclusion : Because "Mokgwaillam" contents are not outright and remarkable in ophthalmology field, "Mokgwaillam" has its limit. On the contrast, we suggest that "Mokgwaillam" could represents speciating ophthalmology field in Traditional Korean Medicine. The reason is that "Mokgwaillam" tried to remake "Dongeuibogam" "Ahn" contents as a ophthalmologic book in some aspects ; contents movement, deletion, transformation and so on.

The Lago Sofia Conglomerate : Debris Flow to Hyperconcentrated Flow Deposits in a Cretaceous Submarine Channel, Southern Chile

  • Choe, Moon-Young;Sohn, Young-Kwan;Jo, Hyung-Rae;Kim, Yea-Dong
    • Ocean and Polar Research
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    • v.24 no.3
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    • pp.289-300
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    • 2002
  • The Lago Sofia conglomerates encased in the Cretaceous Cerro Toro Formation, southern Chile, represent a gigantic submarine channel system developed along a foredeep trough. The channel system consists of several tributaries along the trough margin and a trunk channel along the trough axis. Voluminous debris flows were generated ubiquitously along the tract of the submarine channel mainly by the failure of nearby channel banks or slopes. The flows transformed immediately into multiphase flows and resulted in very thick-bedded mass-flow deposits with a peculiar structure sequence. The mass-flow deposits commonly overlie fluted or grooved surfaces and consist of a lower division of clast-supported and imbricated pebble-cobble conglomerate with common basal inverse grading, and an upper division of clast- to matrix-supported and disorganized pebble conglomerate or pebbly mudstone with abundant intraformational clasts. The structure sequence suggests a temporal succession of a turbidity current, a bipartite hyperconcentrapted flow with active clast collisions near the flow base, and a cohesive debris flow probably with a rigid plug. The multiphase flow is interpreted to have resulted from transformation of clast-rich but cohesive debris flows. Cohesive debris flows appear to transform more easily into dilute flow types in subaqueous environments because they are apt to hydroplane. This is in contrast to the flow transitions in subaerial environments where noncohesive debris flows are dominant and difficult to hydroplane.