• The Korean Journal of Nuclear Medicine Technology
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• v.20 no.1
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• pp.59-65
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• 2016

Purpose Dynamic kidney scan is a typical imaging technique that visualizes kidney function. Reproducibility of dynamic kidney scans has been evaluated by comparing low-dose kidney scans with low-dose radiopharmaceutical and standard dynamic kidney scan. With this comparative study, if reproducibility is superb, the dynamic kidney scan method with reduced radioactivity to patients is to be utilized and radiation exposure to patient is to be reduced. Materials and Methods For gamma camera, Orbiter, SymbiaE (Siemens, Germany) was used. Among patients who had used 370 Mbq (10 mCi) from January of 2013 to February 2014 and other patients who had used 185 Mbq (5 mCi) from March of 2014 to July of 2015 with identical condition, 21 subjects using DTPA and 20 subjects using $MAG_3$, 41 subjects in total, had been selected as subjects for data. From renogram of the result image, frame of the peak point was selected. Then, region of interest of kidney and background had been selected and Kidney to Background Ratio has been calculated for comparison. Results In tests using DTPA, kidney to background ratio when using 370 Mbq was $5.67{\pm}0.8$ at average while it was $5.62{\pm}0.87$ when using 185 Mbq, which didn't show much difference. Also in the tests using $MAG_3$, kidney to background ratio when using 370 Mbq was $14.95{\pm}2.58$ at average and $14.56{\pm}2.02$ in 185 Mbq, which neither showed much difference. In paired sample t-test, p-value was 0.566 in DTPA and 0.363 in $MAG_3$, which confirmed that there was no difference between the groups. Conclusion In identical patients, when dose was decreased from 370 Mbq to 185 Mbq, reproducibility of dynamic kidney scan was proven to be excellent. Low-dose Dynamic kidney scan can achieve results with fine reproducibility without improvement in performance of gamma camera and is expected to reduce radiation exposure to patient.

• Carbon letters
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• v.11 no.2
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• pp.127-130
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• 2010

Boron doped fullerene $C_{60}$ ($B:C_{60}$) films were prepared by the thermal evaporation of $C_{60}$ powder using argon plasma treatment. The morphology and structural characteristics of the thin films were investigated by scanning electron microscope (SEM), Fourier transform infra-red spectroscopy (FTIR) and x-ray photo electron spectroscopy (XPS). The electrochemical application of the boron doped fullerene film as a coating layer for silicon anodes in lithium ion batteries was also investigated. Cyclic voltammetry (CV) measurements were applied to the $B:C_{60}$ coated silicon electrodes at a scan rate of $0.05\;mVs^{-1}$. The CV results show that the $B:C_{60}$ coating layer act as a passivation layer with respect to the insertion and extraction of lithium ions into the silicon film electrode.

• Journal of Industrial Technology
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• v.28 no.A
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• pp.163-166
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• 2008

In this paper, the swept source optical coherence tomography system has realized using a free-space interferometer based on a beam splitter. Personal computer has completed the control for tunable wavelength laser digitally and the B-scan motor as well. From each experiment for an onion and a salmon egg, we confirmed that the in vivo epidermal cross-sectional images for them can be obtained appropriately.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.11B
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• pp.1957-1965
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• 2000

본 논문에서는 휴대 멀티미디어 응용을 위한 MDSP(Multimedia Fixed Point DSP) 칩의 내장 메모리 테스트와 기판 수준의 테스트를 지원하기 위해 내장 메모리 테스트를 위한 자체 테스트 기법, 기판 수준의 테스트 지원 및 내장 메모리를 위한 자체 테스트 회로를 제어하기 위한 경계 주사 기법을 구현하였다. 본 논문에서 구현한 기법들은 Verilog HDL을 이용하여 회로들을 설계하였으며, Synopsys 툴과 현대 heb60 라이브러리를 이용하여 합성하였다. 그리고 회로 검증을 위한 시뮬레이터는 Cadence사의 VerilogXL을 사용하였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.5B
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• pp.685-691
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• 2001

본 논문은 4단계 파이프 라인과 VLIW (Very Long Instruction Word) 구조를 갖는 FLOVA라는 DSP 프로세서의 테스트용이 설계 기법을 다룬다. Full-scan design, BIST(Built-In-Self-Test), IEEE 1149.1의 기법들이 플립플롭과 floaing point unit, 내장된 메모리, I/O cell 등에 각각 적용되었다. 이러한 기법들은 테스트 용이도의 관점에서 FLOVA의 구조에 적절하게 적용되었다. 본 논문에서는 이와 같이 FLOVA에 적용된 테스트 용이 설계의 특징들을 중심으로 상세하게 기술한다.

• Proceedings of the KIEE Conference
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• 1999.07g
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• pp.2885-2887
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• 1999

초고속 영상 기법의 Echo Planar Imaging과 Spiral Scan Imaging 기법은 자기장의 inhomogeneity에 영향을 많이 받게 된다. 본 논문에서는 자기장의 inhomogeneity를 보정하는 기능인 shimming 기능을 자동으로 실행할 수 있는 알고리즘을 구현하였다. 자기장의 inhomogeneity를 보정하기 위해서 자기장에 생성될 수 있는 spherical harmonic function중 1차에 대해 보정을 시도하였고, 기존의 알고리즘보다 뛰어난 결과를 얻을 수 있었다.

• 대한핵의학회:학술대회논문집
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• 1971.11a
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• pp.82.2-82.2
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• 1971

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.9B
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• pp.1643-1651
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• 1999

Video-On-Demand (VOD) is expected to provide the user with interactive operations such as VCR functions. In particular, fast scan functions like “Fast Forward” of “Fast Backward” for a certain speedup playback are required. Since they require a significant amount of system resources, schemes to reduce bandwidth requirements for the network or disk are needed. In MPEG standard, Group-of-Pictures (GoP) is a random access unit which can be decoded independently. Since storing and transmitting a video stream based on GoP is efficient, it is practical to support fast scan functions based on GoP. In this paper, we present a dynamic transmission scheduling scheme to support fast scan functions with m-times normal playback rate for a stored video. The proposed scheme writes a transmission schedule whenever user requests a fast scan function. That is, the scheme constructs the data set to be smoothed by skipping GoPs according to a given speedup factor, and then writes the transmission schedule by applying a bandwidth smoothing. Finally, the scheme restarts the transmission of video data to a client according to the new schedule. The proposed scheme results in speeding up the playback rate by utilizing “GoP skipping”, and then reduces the computational overhead by applying a bandwidth smoothing based on GoP.

• 한국해양학회지
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• v.22 no.3
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• pp.143-152
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• 1987

The digital data were obtained using Kennedy 9000 magnetic tape deck which was connected to the SMS960 side scan sonar during the field operations. The data of three consecutive survey tracks near Seongsan-po, Cheju were used for the development of this study. The softwares were mainly written in Fortran-77 using VAX 11/780 MINI-COMPUTER (CPU Memory; 4MB). The established mapping system consists of the pretreatment and the digital processing of seafloor image data. The pretreatment was necessary because the raw digital data format of the field magnetic tapes was not compatible to the VAX system. Therefore the raw data were read by the personal computer using the Assembler language and the data format was converted to IBM compatible, and next data were communicated to the VAX system. The digital processing includes geometrical correction for slant range, statistical analysis and cartography of the seafloor image. The sound speed in the water column was assumed 1,500 m/sec for the slant range correction and the moving average method was used for the signal trace smoothing. Histograms and cumulative curves were established for the statistical analysis, that was purposed to classify the backscattering strength from the sea-bottom. The seafloor image was displayed on the color screen of the TEKTRONIX 4113B terminal. According to the brief interpretation of the result image map, rocky and sedimentary bottoms were very well discriminated. Also it was shown that the backscattered acoustic pressurecorrelateswith the grain size and sorting of surface sediments.

• The Korean Journal of Nuclear Medicine
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• v.5 no.2
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• pp.57-64
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• 1971

The organ distribution study and the whole body scan were done in the albino rats at intervals of 5, 30, 60, 90 and 120 minutes after the intravenous injection of $^{99m}TC$-pertechnetate absorbed in Sephadex beads of $20{\sim}80$ micra in diameter. Effect of additional injection of physiological saline and saline absorbed in Sephadex beads of $20{\sim}80$ micra in diameter on the scan and organ distribution were also studied. The results were as follows. 1. Five minutes after the injection of $^{99m}TC$-pertechnetate absorbed in Sephadex beads of $20{\sim}80$ micra in diameter, Sephadex was well trapped in the lungs, with which the excellent lung scan was obtained. Two hours after the injection, kidneys were well visualized instead of lungs, which suggested that kidney acts as the excretory organ. Five minutes prior to scan, additional injection of physiological saline absorbed in Sephadex above mentioned was done. The bladder was also well visualized together with the kidneys. 2. In the distribution studies, most of radioactivity was detected in the lungs at 5 minutes and was gradually transferred chiefly to the kidneys and bladder and partly to the liver. 3. Additional injection of physiological saline resulted in a rapid transfer of $^{99m}TC$ trapped in the lung to both the kidneys and liver. 4. Additional injection of physiological saline absorbed in Sephadex beads of $20{\sim}80$ micra in diameter resulted in a rapid transfer of $^{99m}TC$ trapped in the lung to only the urinary system. 5. Results of these studies suggested that; a) Other nutrients and therapeutic compounds may be carried into the lungs along with Sephadex beads and then released in high concentration, which would exert greater therapeutic effect locally than that of the usual administration. b) Some radionuclides absorbed in Sephadex could be used as the lung scan agents, the flushing out of which by Sephadex-saline also give satisfactory renal and bladder scans. c) Other potent therapeutic radionuclides could be retained for some time by this method, which can be in the lungs easily flushed out within 2 hours.