• Title/Summary/Keyword: contrast

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Fusion of Global and Adaptive Methods for Contrast Enhancement of Ultrasound Images (초음파 영상의 콘트라스트 향상을 위한 전역적, 적응적 방법의 융합)

  • Yun, Jae-Ho;Park, Rae-Hong
    • Proceedings of the IEEK Conference
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    • 2007.07a
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    • pp.357-358
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    • 2007
  • Contrast enhancement in the field of ultrasound imaging contributes to improve the accuracy of medical diagnosis by enhancing the visibility of ultrasound images. This paper proposes a contrast enhancement method that improves the contrast of ultrasound images both globally and locally by fusing global and adaptive contrast enhancement methods. Experimental results show that our approach yields more competitive results than the existing global and adaptive contrast enhancement methods in enhancing the visibility of ultrasound images.

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Improved Human Factors of Electroluminescent Displays using Optical Interference Effect

  • Krasnov, Alexey N.;Kim, Woo-Young
    • Journal of Information Display
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    • v.4 no.2
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    • pp.7-12
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    • 2003
  • We discuss main techniques to improve legibility of electroluminescent displays. Emphasis is placed on use of destructive optical interference to cancel ambient light reflected from the back electrode of the device. Basic optical principles and material composition of the optical interference contrast-enhancing stack (CES) are presented. We also describe the improved human factors of electroluminescent devices assisted with a CES. Achromatic contrast is the most important contributor to display's legibility. In some conditions color contrast may also be important. Contributing to both luminance and color contrast enhancement, the contrast-enhancing stack may play an important role in various display applications.

Estimation of Nanomechanical Properties of Nanosurfaces Using Phase Contrast Imaging in Atomic Force Microscopy (원자력현미경의 위상차영상을 이용한 나노표면의 미소기계적 특성 평가)

  • Ahn, Hyo-Sok
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.16 no.5
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    • pp.115-121
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    • 2007
  • Phase contrast imaging in atomic force microscopy showed a promise as an effective tool for better understanding of micromechanical properties of surfaces at nano scale. A qualitative estimation model for phase contrast images obtained with a tapping mode AFM was developed. This investigation demonstrated the high efficiency of combined analysis of topography and phase contrast images for characterizing nanosurfaces. Phase contrast images allowed estimation of relative stiffness(elastic modulus) of the sample surface. The phase contrast images revealed a significant inhomogeneity of the nano scale worn surfaces. Phase contrast images are also capable of revealing the formation of tribofilms.

MR Contrast Agents and Molecular Imaging (MR조영제와 분자영상)

  • Moon, Woo-Kyung
    • The Korean Journal of Nuclear Medicine
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    • v.38 no.2
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    • pp.205-208
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    • 2004
  • The two major classes of magnetic resonance (MR) contrast agents are paramagnetic contrast agents, usually based on chelates of gadolinium generating T1 positive signal enhancement, and super-paramagnetic contrast agents that use mono- or polycrystalline iron oxide to generate strong T2 negative contrast in MR images. These paramagnetic or super-paramagnetic complexes are used to develop new contrast agents that can target the specific molecular marker of the cells or tan be activated to report on the physiological status or metabolic activity of biological systems. In molecular imaging science, MR imaging has emerged as a leading technique because it provides high-resolution three-dimension maps of the living subject. The future of molecular MR imaging is promising as advancements in hardware, contrast agents, and image acquisition methods coalesce to bring high resolution in vivo imaging to the biochemical sciences and to patient care.

A Study on Utility of Magnetic Resonance Imaging for Female Pelvic Cavity using Enteral MRI Contrast Media (Enteral MRI contrast media를 이용한 여성골반 자기공명영상의 유용성)

  • Kim, Ham-Gyum
    • Journal of radiological science and technology
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    • v.20 no.1
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    • pp.29-34
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    • 1997
  • For radiological test in soft tissue or neighboring part with same signal intensity, proper test method and equipment shall be selected as needed. In case of female pelvic cavity, ultrasonography or computed tomography alternatively used, but MRI can be more usefully applied to design treatment method or operation plan by improving the diagnostic accuracy and careful observation of lesion characteristics. Magnetic Resonance Imaging using recently developed Enteral MRI contrast media can acquire more diagnostic information than using only intravenous contrast media. Thus this study attempted to examine the utility of anatomic structure and diagnostic acquisition by imaging the female pelvic cavity using Enteral MRI contrast media. As a result of analyzing magnetic resonance Imaging after administering Enteral MRI contrast media to pelvic cavity suspect patients, more diagnostic information media could be acquired than only using Intravenous contrast. Expecially, in the diagnosis of lesion position, shape, distinction from neighboring tissues it is thought that external Enteral MRI contrast media should be used.

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The Design and Implementation of Real Time Contrast Enhancer System for High Resolution FPD (고해상도 FPD를 위한 실시간 Contrast Enhancer System의 설계 및 구현)

  • Seo, Bum-Suk;Choi, Chul-Ho;Kwon, Byeong-Heon
    • Journal of Digital Contents Society
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    • v.5 no.1
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    • pp.79-86
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    • 2004
  • In this paper we implemented the Real Time Contrast Enhancer for image quality enhancement of moving picture. Also we proposed adaptive contrast method that use mean and variance of input video signal. The Designed the contrast Enhancer is measured in comparison with conventional picture and interfaced to 30inch TFT LCD TV of the LG Electronics.

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Application of Local Histogram and Plateau Equalization Algorithm for Contrast Enhancement of Real Time Thermal Image (실시간 열영상 대조비 개선을 위한 대역추출 및 플래토 평활화 알고리즘 적용)

  • 조흥기;김수곤;전희종
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.53 no.2
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    • pp.76-85
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    • 2004
  • In this paper, the contrast enhancement method of thermal image is proposed and it is the plateau equalization algorithm using local histogram for the real time display of infrared imagery. Through hardware implementing, its practicality and adequacy are proved. Examinations are executed to verify the effect of contrast enhancement by bright control and contrast control automatic to the plateau value in the manual mode, and that verified the effect of contrast enhancement in the automatic mode and the practicality in the real system. According to the experiment results, the proposed "the application of local histogram and plateau equalization algorithm for contrast enhancement of real time thermal image"in this dissertation is the verified method for the thermal imaging contrast enhancement.

Contrast Enhancement for X-ray Images Based on Combined Enhancement of Scaling and Wavelet Coefficients (웨이브렛과 기저 계수를 이용한 X-ray 영상의 대조도 향상기법)

  • Park, Chun-Joo;Kim, Do-Il;Jang, Do-Yoon;Yoon, Han-Been;Choe, Bo-Young;Kim, Ho-Kyung;Lee, Hyoung-Koo
    • Progress in Medical Physics
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    • v.19 no.3
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    • pp.150-156
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    • 2008
  • An applied technique of contrast enhancement for X-ray image is proposed which is based on combined enhancement of scaling and wavelet coefficients in discrete wavelet transform space. Conventional contrast enhancement methods such as contrast limited adaptive histogram equalization (CLAHE), multi-scale image contrast amplification (MUSICA) and gamma correction were applied on scaling coefficients to enhance the contrast of an original. In order to enhance the detail as well as reduce the blurring caused by up scaling of contrast modified scale coefficients from lower resolution, the sigmoid manipulation function was used to manipulate wavelet coefficients. The contrast detail mammography (CDMAM) phantom was imaged and processed to measure the image line profile of results and contrast to noise ratio (CNR) comparatively. The proposed technique produced better results than direct application of various contrast enhancement methods on image itself. The proposed method can enhance contrast, and also suppress the amplification of noise components in a single process. It could be useful for various applications in medical, industrial and graphical images where contrast and detail are of importance.

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Safety Evaluation of Iopamidol Contrast Medium Used for Radiological Examination of a Local Clinic in Korea (방사선 검사에 사용되는 조영제 Iopamidol의 안전성 평가)

  • Park, Chang-Mook;Lee, Bo-Reum;Song, Tea-Bum;Jang, Je-Kwan;Lee, Yu-Jeung;Lee, Myung-Koo;Lim, Sung-Cil
    • YAKHAK HOEJI
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    • v.53 no.6
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    • pp.328-333
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    • 2009
  • Contrast media are substances that are used to enhance the contrast of structures or fluids within the body in medical imaging. Those are commonly used to enhance the visibility of blood vessels and the gastrointestinal tract. The aim of this study is to evaluate patients who got injected iopamidol, developed as one of contrast medium regarding changes in cardiovascular system and especially, adverse drug reactions. This study were performed on randomly selected a total of 51 patients (range of 15~85 years old) who got injected contrast medium, Iopamidol at a P hospital in Gyeonggi province from September 22nd, 2008 to January 24th, 2009. Data were collected by questionnaire though person to person. We analyzed the data by SPSS (Version 12. for windows). Methods of analysis were frequency and cross analysis. In results, 19.6% (n=10) were founded for adverse drug reactions of contrast medium. 25.0% (n=4) of 10 patients who had adverse drug reactions of contrast medium had took abdomen contrast test. 2 patients of those took contrast test for chest. Also, 3.9% (n=2) patients felt vomiting and nausea after injection of contrast medium. In conclusion, 19.6% patients experienced adverse drug reaction of contrast medium. Therefore, when taking radiation test, we should make efforts to minimize adverse drug reactions to achieve suitable and effective treatment.

Oral Administration of Nonionic Water-Soluble Contrast Media to Treat Meconium Obstruction in Premature Infants: A Preliminary Study

  • Hong, Hyun Sook;Kim, Sung Shin;Park, Ga Young
    • Neonatal Medicine
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    • v.28 no.1
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    • pp.22-28
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    • 2021
  • Purpose: Meconium obstruction of prematurity (MOP) predisposes premature infants to intestinal perforation and prolonged hospitalization if not diagnosed and treated promptly. A standard contrast enema is less effective to treat infants with distal ileal obstructions because the contrast may not reach the obstructed areas. In an effort to avoid risky surgery, we administered oral contrast media to seven clinically diagnosed patients with MOP whose obstructions were not relieved via conventional sonography-guided contrast enema. We retrospectively evaluated whether oral nonionic water-soluble contrast media relieves MOP. Methods: Seven of 67 premature infants with MOP were administered oral contrast media from June 2015 to January 2019. Patients were followed-up radiographically for bowel distention and evacuation of contrast media after oral administration. We recorded radiographic improvements, meconium evacuation, time to first feeding after oral contrast media administration, maternal history, and neonatal clinical factors. Results: We evaluated five male and two female infants. The median gestational ages and body weights at birth were 27+5 weeks and 890 g, respectively. Radiography in five infants revealed multiple distended intestinal loops without air-fluid interfaces. Two infants had gasless abdomens, in which only stomach gas was visible. Oral contrast media (median, 2.5 mL) were administered at a median age of 7 days; five infants (5/7, 71.4%) responded to this treatment. The remaining two infants, who had ileal stenosis and hypoganglionosis, were surgically managed. Five infants (5/7, 71.4%) had maternal risk factors, and two (28.6%) were small for gestational age. Conclusion: Nonionic oral water-soluble contrast medium can serve as a valuable adjunct treatment in premature infants with meconium obstruction.