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대향2문조사시 Target Volume의 위치에 따른 Beam Weight의 최적화

  • Lee Jin Guk;Kim Ji Han;Im Ik Su;Choe Yeong Heon
    • The Journal of Korean Society for Radiation Therapy
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    • v.5 no.1
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    • pp.68-73
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    • 1992
  • If the same weight is used in parallel opposed 6 and 10 MV x-ray beams, the lowest dose is achieved at SAD. Therefore, dose homogeneity in the target volume is decreased when SAD is taken at center of target volume than center of phantom or patient. With Standard deviation of ${\pm}6\%$ that repuesented the dose homogeneity in tarhet volume, we studied the optimized beam weights at which hot spot dose was least in parallel opposed beams. The optimized beam weights that maximally decrease the hot spot dose, wer 1.29, 1.19, 2.71, 3.50, and 4.70 in 6 MV x-ray and 1.25, 1.53, 1.90, 2.36, 3.01, and 3.7 in 10 MV x-ray, reapectively, when center of target volume was changed to 2,4,6,8,10, and 12cm from center plan of phantom along the centeral axis of beams.

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In Situ Observation of Initial Rusting Process of Steel Containing Al Using Synchrotron Radiation X-Rays

  • Morimoto, J.;Yamashita, M.;Uchida, H.;Doi, T.;Kamimura, T.;Miyuki, H.;Konishi, H.;Mizuki, J.
    • Corrosion Science and Technology
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    • v.7 no.2
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    • pp.112-118
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    • 2008
  • We observed initial rusting process of steel containing Al under wet/dry cyclic condition with NaCl solution film using in situ X-ray diffraction spectroscopy at SPring-8 synchrotron radiation facility. It was found that mass fraction of iron oxides such as ${\alpha}-FeOOH$, ${\beta}-FeOOH$ and ${\gamma}-FeOOH$ varied with Al content. Some kinds of Al oxides were also found at the initial stage of corrosion. Those corrosion products might affect the corrosion process and corrosion rate of the steel.

Design of High-Performance Unified Circuit for Linear and Non-Linear SVM Classifications

  • Kim, Soo-Jin;Lee, Seon-Young;Cho, Kyeong-Soon
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.12 no.2
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    • pp.162-167
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    • 2012
  • This paper describes the design of a high-performance unified SVM classifier circuit. The proposed circuit supports both linear and non-linear SVM classifications. In order to ensure efficient classification, a 48x96 or 64x64 sliding window with 20 window strides is used. We reduced the circuit size by sharing most of the resources required for both types of classification. We described the proposed unified SVM classifier circuit using the Verilog HDL and synthesized the gate-level circuit using 65nm standard cell library. The synthesized circuit consists of 661,261 gates, operates at the maximum operating frequency of 152 MHz and processes up to 33.8 640x480 image frames per second.

Staistical analysis and measurements of array receivers for use in optical communication (광통신에 이용되는 배열 수신기의 측정과 통계적 해석)

  • Sung, Pyung-Shik
    • Journal of the Korea Computer Industry Society
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    • v.8 no.1
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    • pp.57-64
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    • 2007
  • In the paper, considers the design of a detection system, consisting of n identical detectors, to process the sum of spatially invariant signal fields $S_\jmath(t)$, an additive, homogeneous, spatially isotropic (in the array plane x). covariance_separable, and zero_mean Gaussian random noise field n(t, x). consisting of arrey receivers for use in optical communication through optimum turbulence atmosphers and covriance_circuit, staistical analysis through detection the maximum gain are compared with analysis theoretical analysis theoretical value and get through experimental measured value, as well the measured valus are confirmed to agreement joint Gaussian theoretical curves.

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A study on the solutions of the 2nd order linear ordinary differential equations using fourier series (Fourier급수를 응용한 이계 선형 상미분방정식의 해석에 관한 연구)

  • 왕지석;김기준;이영호
    • Journal of Advanced Marine Engineering and Technology
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    • v.8 no.1
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    • pp.100-111
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    • 1984
  • The methods solving the 2nd order linear ordinary differential equations of the form y"+H(x)y'+G(x)y=P(x) using Fourier series are presented in this paper. These methods are applied to the differential equations of which the exact solutions are known, and the solutions by Fourier series are compared with the exact solutions. The main results obtained in these studies are summarized as follows; 1) The product and the quotient of two functions expressed in Fourier series can be expressed also in Fourier series and the relations between the Fourier coefficients of the series are obtained by multiplying term by term. 2) If the solution of the 2nd order lindar ordinary differential equation exists in a certain interval, the solution can be obtained using Fourier series and can be expressed in Fourier series. 3) The absolute errors of Fourier series solutions are generally less in the center of the interval than in the end of the interval. 4) The more terms are considered in Fourier series solutions, the less the absolute errors.rors.

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Effect of UO2+x Powders Produced at Different Oxidation Temperatures on the Properties of Pellet

  • Yoo, Ho-Sik;Lee, Seung-Jae;Kim, Jae-Ik;Song, Kun-Woo
    • Journal of the Korean Ceramic Society
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    • v.40 no.5
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    • pp.410-414
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    • 2003
  • Characteristics of $UO_{2+x}$ powders oxidized at different temperatures were examined. Pellets were fabricated by adding these oxidation powders and their properties were also investigated. Particle size of the $UO_{2+x}$ powders decreased with increasing oxidation temperature while surface area increased. Only the powders oxidized at 35$0^{\circ}C$ enhanced the strength of green pellet. However, 35$0^{\circ}C$ oxidized powders added pellet had many surface defects. The difference of shrinkage rate between the oxidized and UO$_2$ powders was thought to be the cause of them.

Localized pleural mesothelioma -A case report- (Localized pleural mesothelioma -수술치험 1예-)

  • Gu, Bon-Il;Son, Gwang-Hyeon;Go, Il-Hyang
    • Journal of Chest Surgery
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    • v.19 no.2
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    • pp.295-299
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    • 1986
  • Pleural mesothelioma is the tumor of the cell of mesodermal origin lining the pleura. It is relatively uncommon tumor and its localized form is much rarer than diffuse form. Authors experienced a localized mesothelioma in a patient who was 44 year old male worker at copper plumbing field for 20 years, and admitted due to incidentally found abnormal chest X-ray. Exploratory thoracotomy was done and a 23 x 16 x 8 cm sized solitary mass was resected with adherent right middle lobe. Low grade malignancy of the pleural mesothelioma was confirmed by the pathology. We report the case with a literature review.

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DSP TMS320F281x의 특성 및 전동기 구동장치 응용방식

  • 전태원;이홍희
    • KIPE Magazine
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    • v.9 no.3
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    • pp.13-17
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    • 2004
  • 근래에 Texas Instruments(TI)사에서 개발된 TMS3320LF240x는 고정 소숫점 방식의 16비트 DSP으로써 저가, 고성능용으로 개발된 칩이다. 이 DSP는 비교적 빠른 계산속도에 다양한 입력/출력장치를 내장하고 있으므로 DSP 장점과 마이크로제어기의 장점을 모두 가지고 있다. 특히 Flash 메모리, RAM 등 메모를 포함하여 8-16채널 이상 A/D 컨버터, Timer, 직력통신과 함께 PWM인버터/컨버터용 PWM펄스까지 출력시킬 수 있으므로, 이 DSP는 각종 전동기 구동시스템과 SUP, 능동필터 제어 등 전력전자 분야에서 적합하게 설계된 DSP로 상당히 많이 사용되고 있다. 그런데 TMS320LF240x는 고정 소숫점 방식의 16비트 DSP이므로 연산량이 많은 시스템에서는 적용하기 힘들며, 또는 저장할 데이터량이 많은 제어시스템일 경우에는 내장된 flash 및 SRAM 등 메모리 용량이 부족하는 등 사용하는데 문제가 있을 가능성이 있다.(중략)

A Study on the X-ray Diffraction of the Muscle by the Electrical Stimulation (근육의 전기자극에 의한 X선 회절 분석연구)

  • 김덕술;송주영
    • Journal of Life Science
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    • v.8 no.4
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    • pp.373-380
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    • 1998
  • A considerable change observed in X-ray diffraction during the muscle contraction was that the movement of myosin head and conformational change of contractile monecules were occurred in the muscle contraction. Time slice requires tension peak after the onset of stimulation and the height of tension peak depends on the number of twitch cycle. The intensity of I$_{11}$, I$_{10}$, 143${\AA}$ reflection is measured with 5ms time resolution and is recorded in isometric tension. The peak height of I$_{11}$ and 143${\AA}$ intensity is changed after the onset of a stimulation I$_{i}$, and the length of twitch is shortened by successive twitches in the case of stimulation TI$_{i}$. On the other hand, the peak height of I$_{11}$ and 215${\AA}$ intensity starts to decrease at the 1st twitch and remains constant at low peak hight without appreciable recovery during the contraction term. In the case of uccessive twitch stimulation, the myosin heads of muscle are once moved from their resting position and never returned to their initial position.

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Primary Mediastinal Seminoma: A Case Report (원발성 종격동 정상피종: 1례 보고)

  • Lee, In-Sung;Kim, Hyoun-Mook
    • Journal of Chest Surgery
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    • v.11 no.2
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    • pp.170-174
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    • 1978
  • A case of mediastinal seminoma is presented. A male driver, 27 years old Korean, has been suffered from substernal pain, cough and moderate swallowing difficulty since 5 months prior to this admission. At the time of onset, he visited at a local clinic to find some mass in his anterior mediastinum on chest P-A and lateral X-ray check. Recently, intermittent hiccups with much aggravated dysphagia forced him to visit our hospital, and admitted for radical resection under the impression of anterior superior mediastinal tumor of thymus origin. Median sternotomy was done and total resection of the tumor of 8.0X11.0X3.5cm was done without any specific complication and biopsy of the tumor revealed as primary mediastinal seminoma of the mediastinum. Supplementary prophylactic irradiation therapy was done with a tumor dose of 4,000 rad in 4 weeks after operation. Postoperative hospital course was uneventful and patient was joyful with his occupation for 3 months after discharge.

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