• Title/Summary/Keyword: image uniformity

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Effects of Oxidizer Additive on the Performance of Copper-Chemical Mechanical Polishing using Tungsten Slurry (텅스텐 슬러리를 사용한 Cu-CMP 특성에서 산화제 첨가의 영향)

  • 이우선;최권우;이영식;최연옥;오용택;서용진
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.17 no.2
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    • pp.156-161
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    • 2004
  • We investigated the effects of oxidizer additive on the performance of Cu-CMP process using commonly used tungsten slurry. In order to compare the removal rate and non-uniformity as a function of oxidizer contents, we used alumina-based tungsten slurry and copper blanket wafers deposited by DC sputtering method. According to the CMP removal rates and particle size distribution, and the microstructures of surface layer by SEM image as a function or oxidizer contents were greatly influenced by the slurry chemical composition of oxidizers. The difference in removal rate and roughness of copper surface are believed to cause by modification in the mechanical behavior of $Al_2$O$_3$abrasive particles in CMP slurry.

Changes in Image Quality and Dose according to Exposure Parameters of Brain CT (두부 CT의 노출 파라메타에 따른 화질과 선량의 변화)

  • Choi, Seok yoon;Im, In Chul
    • Journal of the Korean Society of Radiology
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    • v.13 no.5
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    • pp.705-711
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    • 2019
  • Currently, the brain CT scan of the latest equipment lacks the study of parameter change and dose change and especially of noise, uniformity analysis and dose change. Therefore, this study attempted to study the phenomenon that occurs at this time by analyzing tube voltage, slice thickness, and pitch change in exposure parameters when using high specification CT. Experimental results show that uniformity is better when using high voltage, thick slice thickness selection, and minimum pitch. As a result of the combination, the most uniformity condition was 140 kVp, 10 mm and pitch 0.5. Noise was found to be improved regardless of pitch by increasing tube voltage and slice thickness. The radiation dose increased linearly with tube voltage and pitch. Therefore, the results of this study will serve as a reference for the use of High specification brain CT.

A Study on Image Improvement using Multiple Cameras (다중 카메라를 이용한 영상 개선에 관한 연구)

  • Kim, Seok-Jin;Kim, Yong-U;Yun, Sang-Won;Kim, Che-Eun;Lee, Seung-Dae
    • The Journal of the Korea institute of electronic communication sciences
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    • v.13 no.4
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    • pp.859-864
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    • 2018
  • This paper is about image improvement - we used the contrast ratio and the outline emphasis method after synthesizing two low quality images utilized by several low definition cameras. Two raspberry cameras were used to capture each image, and then we synthesized images with MATLAB program. After applying the mean computation (alignment, geometry, and harmony) to synthesized image, we extracted the cross-space. In the experiment of this study, we identified and compared the improvement consequences of extracted, synthesized image after applying outline emphasis(unsharpmask filter, highboost filter) and increasing contrast ratio (histogram uniformity, histogram stretching) to the original images.

Change of PET Image According to CT Exposure Conditions (CT 촬영 조건에 따른 PET 영상의 변화)

  • Park, Jae-Yoon;Kim, Jung-hoon;Lee, Yong-Ki
    • Journal of the Korean Society of Radiology
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    • v.13 no.3
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    • pp.473-479
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    • 2019
  • PET-CT improves performance and reduces the time by combining PET and CT of spatial resolution, and uses CT scan for attenuation correction. This study analyzed PET image evaluation. The condition of the tube voltage and current of CT will be changed using. Uniformity phantom and resolution phantom were injected with 37 MBq $^{18}F$ (fluorine ; 511 keV, half life - 109.7 min), respectively. PET-CT (Biograph, siemens, US) was used to perform emission scan (30 min) and penetration scan. And then the collected image data were reconstructed in OSEM-3D. The same ROI was set on the image data with a analyzer (Vinci 2.54, Germany) and profile was used to analyze and compare spatial resolution and image quality through FWHM and SI. Analyzing profile with pre-defined ROI in each phantom, PET image was not influenced by the change of tube voltage or exposure dose. However, CT image was influenced by tube voltage, but not by exposure dose. When tube voltage was fixed and exposure dose changed, exposure dose changed too, increasing dose value. When exposure dose was fixed at 150 mA and tube voltage was varied, the result was 10.56, 24.6 and 35.61 mGy in each variables (in resolution phantom). In this study, attenuation image showed no significant difference when exposure dose was changed. However, when exposure dose increased, the amount of dose that patient absorbed increased too, which indicates that CT exposure dose should be decreased to minimum to lower the exposure dose that patient absorbs. Therefore future study needs to discuss the conditions that could minimize exposure dose that gets absorbed by patient during PET-CT scan.

Improvement of Hysteresis Characteristics of Low Temperature Poly-Si TFTs (저온 Poly-Si TFT 소자의 Hysteresis 특성 개선)

  • Chung, Hoon-Ju;Cho, Bong-Rae;Kim, Byeong-Koo
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.2 no.1
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    • pp.3-9
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    • 2009
  • Although Active matrix organic light emitting diode (AMOLED) display has a better image quality in terms of viewing angle, contrast ratio, and response time than liquid crystal displays (LCDs), it still has some critical issues such as lifetime, residual images, and brightness non-uniformity due to non-uniformity in electrical characteristics of driving TFTs and IR drops on supplied power line. Among them, we improved irrecoverable residual images of AMOLED displays which is mainly related to the hysteresis characteristics of driving TFTs. We consider four kinds of surface treatment conditions before gate oxide deposition for improving hysteresis characteristics. We can reduce the hysteresis level of p-channel TFT to 0.23 V, interface trap states between the poly-Si layer and gate insulator to $3.11{\times}10^{11}cm^{-2}$, and output current variation of p-channel TFT to 3.65 % through the surface treatment using ultraviolet light and H2 plasma. Therefore, the recoverable residual image problem of AMOLED displays can be improved by surface treatment using ultraviolet light and $H_2$ plasma.

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A Study of Flexible Identity Design System (가변적 아이덴티티 시스템에 관한 고찰)

  • Kim, Min
    • Archives of design research
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    • v.13 no.3
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    • pp.303-312
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    • 2000
  • Identity Design System, based on the principle of market economy, has developed over last half a century. The essence of identity program is to establish the corporate Image from dispersion to integral ion through design. There is no doubt that identity design became an inevitable necessity as a market In tool . The circumstance of corporate identity, however , has been changed since the revolution of telecommunication by computer which had an important effect upon today's market The development of computer communication allows people with different taste to achieve their needs from var ious kinds of information. Today's market is shitting from uniformity to diversity It is more difficult to create a corporate Image through conventional method. To meet the challenges of today's market, the communication of corporate identity will ultimately reflect the complexity of the market by adapting the flexible conoept of identity design. The level of flexibility in identity system should be determined depending on the management and market Eng strategy. Flexible Identity System (FIS) would be the best solution for some cases such as; a company with various fields, a company with sensitivity to the contemporary trend, and a company with an emotional appeal to consumers. FIS, with the capacity of a chameleon, can not only adopt the various circumstantial flanges, but also maintain the up-to-date corporate image .

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CCD Pixel Correction Table Generation for MSC

  • Kim Young Sun;Kong Jong-Pil;Heo Haeng-Pal;Park Jong-Euk;Paik Hong-Yul
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.471-474
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    • 2004
  • Not all CCD pixels generate uniform value for the uniform radiance due to the different process of manufacture and each pixel characteristics. And the image data compression is essential in the real time image transmission because of the high line rate and the limited RF bandwidth. This pixel's nonuniformity and the loss compression make CCD pixel correction necessary in on-orbit condition. In the MSC system, the NUC unit, which is a part of MSC PMU, is charge of the correction for CCD each pixel. The correction is performed with the gain and the offset table for the each pixel and the each TDI mode. These correction tables are generated and programmed in the PMU Flash memory through the various image data tests at the ground test. Besides, they can be uploaded from ground station after onorbit calibration. This paper describes the principle of the table generation and the test way of the non-uniformity after NUC

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The Study of Symbolic Images in Modern Fashion Design adopting the Dualistic Meanings of Uniform (유니폼의 양면성을 도입한 현대 패션디자인의 상징적 이미지에 대한 연구)

  • Kwon, Gi-Young
    • The Korean Fashion and Textile Research Journal
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    • v.13 no.4
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    • pp.478-486
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    • 2011
  • This study is to analyze the symbolic images appeared in modern fashion design adopted dualistic meanings in uniforms. Uniforms signify order, conformity and discipline in public life. The dualistic meanings in uniforms appeared modern times are as follows: public authority vs individual non-authority, heterosexual identity vs homosexual identity, time-space uniformity vs mixed diversity. The symbolic images appeared in modern fashion design adopted dualistic meanings in uniforms such as military uniforms, school uniforms, nurses' uniforms, sports uniforms and etc. are erotic image, hybrid image, and kitsch image.

Ellipso-Microscopic Observation of Titanium Surface under UV-Light Irradiation

  • Fushimi, K.;Kurauchi, K.;Nakanishi, T.;Hasegawa, Y.;Ueda, M.;Ohtsuka, T.
    • Corrosion Science and Technology
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    • v.15 no.6
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    • pp.265-270
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    • 2016
  • The ellipso-microscopic observation of a titanium surface undergoing anodization in $0.05mol\;dm^{-3}$ of $H_2SO_4$ was conducted. During irradiation by ultra-violet (UV) light with a wavelength of 325 nm, the titanium surface allowed for the flow of a photo-induced current and showed up as a bright, patch-like image on an ellipso-microscopic view. The brightness and patch-pattern in the image changed with flowing photo-induced current. The changes in the brightness and the image corresponded to the formation and/or degradation of titanium oxide due to the photo-electrochemical reaction of the oxide. An in situ monitoring using the ellipso-microscope revealed that the film change was dependent on the irradiation light power, by UV-light increases the anodic current and results in the initiation of pitting at lower potentials as compared with the non-irradiated condition.

Transform Trellis Image Coding Using a Training Algorithm (훈련 알고리듬을 이용한 변환격자코드에 의한 영상신호 압축)

  • 김동윤
    • Journal of Biomedical Engineering Research
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    • v.15 no.1
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    • pp.83-88
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    • 1994
  • The transform trellis code is an optimal source code as a block size and the constraint length of a shift register go to infinite for stationary Gaussian sources with the squared-error distortion measure. However to implement this code, we have to choose the finite block size and constraint length. Moreover real-world sources are inherently non stationary. To overcome these difficulties, we developed a training algorithm for the transform trellis code. The trained transform trellis code which uses the same rates to each block led to a variation in the resulting distortion from one block to another. To alleviate this non-uniformity in the encoded image, we constructed clusters from the variance of the training data and assigned different rates for each cluster.

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