• Title/Summary/Keyword: Back scan mechanism

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Design of the Step-stare Image Gathering System for an Aerial Reconnaissance (항공 정찰용 Step-stare 영상획득 시스템 설계)

  • Baek, Woonhyuk;Park, Jaeyoung;Ahn, Junghun;Lee, Jungsuk
    • Journal of the Korean Society for Precision Engineering
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    • v.31 no.9
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    • pp.813-820
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    • 2014
  • This paper presents design and performance validation of a method for motion compensation using fast steering mirror. First of all, the schematics of the Electro Optical/Infra-Red (EO/IR) and step-stare image gathering system for an aerial reconnaissance are introduced. Because of the steering mirror with low inertia so called Back scan mechanism (BSM), the fast step-stare image gathering technique that is required for taking a high-definition still image will be realized. After then, the BSM hardware includes motors and feedback sensors are introduced. Also, the motion profile for BSM will be designed to compensate roll scan motion of the gimbals. At the end of this paper, designed profile and tracking performance of the EO/IR system with BSM will be validated through experiments.

Renal Localization of Ga-67 Citrate in Noninfectious Nephritis (비세균성 신염환자에서 신장내 $^{67}Ga-Citrate$ 흡수에 관한 연구)

  • Lee, Kang-Wook;Jeong, Min-Soo;Rhee, Sunn-Kgoo;Kim, Sam-Yong;Shin, Young-Tai;Ro, Heung-Kyu
    • The Korean Journal of Nuclear Medicine
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    • v.26 no.2
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    • pp.318-326
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    • 1992
  • Ga-67 citrate scan has been requested for detection or follow-up of inflammatory or neoplastic disease. Visualization of Ga-67 citrate in the kidneys at 48 and 72 hr post injection is usually interpreted as evidence of renal pathology. But precise mechanisms of abnormal Ga-67 uptake in kidneys were unknown. We undertook a study to determine the clinical value of Ga-67 citrate imaging of the kidneys in 68 patients with primary or secondary nephropathy confirmed by renal biopsy and 66 control patients without renal disease. Renal uptake in 48 to 72 hr images was graded as follows: Grade 0=back-ground activity:1=faint uptake greater than background;2=definite uptake, but less than lumbar vertebrae; 3=same uptake as lumbar vertebrae, but less than liver; 4=same or higher uptake than liver. The results were as follows. 1) 42 of 65 (62%) patients with noninfectious nephritis showed grade 2 or higher Ga-67 renal uptake but only 10 percent of control patients showed similar uptake. 2) In 14 patients with systemic lupus erythematosus, 8 of 9 (89%) patients with lupus nephritis exhibited marked renal uptake 3) 36 of 41 patients (88%) with combined nephrotic syndrome showed Grade 2 or higher renal uptake. 4) Renal Ga-67 uptake was correlated with clinical severity of nephrotic syndrome determined by serum albumin level, 24 hr urine protein excretion and serum lipid levels. 5) After complete remission of nephrotic syndrome, renal uptake in all 8 patients who were initially Grade 3 or 4, decreased to Grade 1 or 0. In conclusion, we think that the mechanism of renal Ga-67 uptake in nephrotic syndrome might be related to the pathogenesis of nephrotic syndrome. In systemic lupus erythematosus, Ga-67 citrate scan is useful in predicting renal involvement.

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