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Epithermal Neutron Flux Enhancement Using SMA in Designing a Cf-Based Neutron Beam for BNCT

  • Kim, Do-Heon;Kim, Jong-Kyung
    • Proceedings of the Korean Nuclear Society Conference
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    • 1995.05a
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    • pp.937-942
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    • 1995
  • Great interest has prompted Boron Neutron Capture Therapy (BNCT) as a new treatment for brain tumors. The use of $^{252}$Cf as a neutron source for BNn makes the in-hospital treatments of tumors to be possible. Newly proposed subcritical multiplying assemblies (SMA) are explored to improve relatively tow neutron fluxes of the source and construct the feasibilities of $^{252}$Cf as a neutron source. The MCNP code has been used to evaluate the effective multiplication factor of the entire system and the intensities and percentages of epithermal neutron flux at the patient-end surface of the system. The neutron beam using SMA shows the epithermal neutron flux enhancement of about 13 times as large as the beam without using SMA. It is expected that the neutron beam proposed in this research will be more effective for treatment of tumors due to the increased therapeutic neutron fluxes.

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더덕 ( 사삼 )의 재배방법별 일반성분 및 무기성분에 관한 연구 ( Proximate and Mineral of Dried Wild and Cultivated Codonopsis lanceolata Benth , et Hook , Fil , of Different Cultivated Groups )

  • 신수철
    • Korean Journal of Plant Resources
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    • v.4 no.2
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    • pp.39-45
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    • 1991
  • Proximate compositions of the roots of cultured and wild Codonopsis lanceolata were examined as tile basic reasearch for the study of their source of processed foods.No significant difference in the contents was found between the wild root and thecultivated at 3$0^{\circ}C$ in biotronroom. In view of the results to have measured mineralswhich is included in 14 sorts of Codonopsis lanceolata and surveyed their distribution.12 kinds of minerals including T1, Co, Ge, Sm, Mo, Sc, Be, Cd, As, Ga, Bi, ph are ne-vel or little included in almost source. Other twenty-one sorts of minerals (Ni, Se,Ba, Sb, Si, Ti, B, Li, Ifs, Ca, Sr, Mn, Fe, Cu, Zn, p, Al, Na, V, Cr, K) are more or less in-cluded in all source and Ca, Mg, p, K, and Fe are metals that are included in large qu-entities in comparison with others. No minerals difference in the contents was foundbetween the cultivated temperature. The content of elements of inorganic metal differsaccording to the part of C. lanceolata.

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Comparison between Two 450 mm Multi-Electrode Models

  • Park, Gi-Jeong;Lee, Yun-Seong;Yu, Dae-Ho;Lee, Jin-Won;Jang, Hong-Yeong
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.490-490
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    • 2013
  • In semiconductor industry, it is expected that plasma process which use 450 mm source will be used at next generation. However, main obstacle of the large area plasma source is plasma uniformity from it. When electrode is enlarged, field difference between center area and side area reduces the plasma uniformity [1-3]. Therefore we investigate multi-electrode which diminish this field difference.We designed two multi-electrode models. One has two segments and the other has five segments. Each multi-electrode model is connected with two power generator and two matchers. One generator and one matcher is connected with center electrode part. The other one generator and the other one matcher is connected with side electrode part. The ion density is measured at 29 points by using floating harmonic method [4-6]. After measuring the data of each multi-electrode model, we discuss the difference of profile between two models' data.

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Study of Back-Up Electric Power Source as a Role for Instant Power Industry Safety by Super Capacitor (순간 정전시 산업안전용 보조전원 역할의 Super Capacitor에 관한 연구)

  • 김상길;김종철;허진우;김경민;이용욱;강안수
    • Proceedings of the Safety Management and Science Conference
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    • 1999.11a
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    • pp.345-354
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    • 1999
  • A new type of capacitor named "Super Capacitor" has been developed, in which the properties of electric double layer formed at the interface of activated carbon electrode- liquid organic electrolyte is applied. This capacitor is small In size, light in weight, wide In temperature range(-25~$70^{\circ}C$), large in charge-discharge capability and good in voltage preservation. And this super capacitor is applied as a power back-up for electricity failure in volatile memory devices etc., a power source for a short time and a power source for operating actuators. At present the development of high power back-up types of the capacitor system and improvement of their characteristics are being actively conducted in order to find wider applications.lications.

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Design of Crosstalk Compensation Circuit in TFT-LCDs (박막트랜지스터 액정표시소자의 화소간섭 보상회로설계)

  • 정윤철;박종철;김이섭
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.32B no.11
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    • pp.1374-1382
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    • 1995
  • In TFT-LCDs, as the display size area becomes larger, and the resolution higher, we have to consider the image degradation effects due to the incorporation of the TFT-LCD parameters such as the data-line resistance, the common electrode resistance, the data-line to common parasitic capacitance, and the output characteristics of driver ICs. One of the degradation effects is crosstalk resulting from the coupling between the source bus-line and common electrode. Since a source signal which represents a large number of display data is supposed to vary frequently, the common signal level is affected through the coupling effect, resulting in the degradation of nearby pixel drive signals. Therefore, we proposed a method to compensate for this source-common electrode coupling effect, we also designed and experimented the feasibility of our crosstalk compensation circuit in the actual TFT-LCD. We saw that the newly designed compensation circuit greatly reduced the crosstalk in display pattern image.

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A Study on Performance Characteristics of A Single Effect LiBr/Water Refrigeration Cycle (단효용 LiBr/물 흡수식 냉동사이클의 성능특성에 관한 연구)

  • 연제문;임삼택;오주원;이경우
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2001.05a
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    • pp.95-99
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    • 2001
  • As a way to use energy effectively, the present study is aimed at investigating the performance characteristics of a Single Effect LiBr/Water Absorption Refrigerator using a low temperature driving heat-source. It was carried out by changing the driving heat-source temperature, the cold water outlet temperature(the refrigeration load), the cooling water inlet temperature, and the weak solution flow rate and this study compares the performance characteristics of refrigerator against the existence and non-existence of the Recirculation of the Weak solution which is used as a method to improve the performance of refrigerator. In case of Recirculation of the weak solution, more improved the Refrigeration Capacity and COP was obtained, and these effects became more larger in the high temperature of driving heat-source and large quantity of solution.

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Application of a deep learning algorithm to Compton imaging of radioactive point sources with a single planar CdTe pixelated detector

  • Daniel, G.;Gutierrez, Y.;Limousin, O.
    • Nuclear Engineering and Technology
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    • v.54 no.5
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    • pp.1747-1753
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    • 2022
  • Compton imaging is the main method for locating radioactive hot spots emitting high-energy gamma-ray photons. In particular, this imaging method is crucial when the photon energy is too high for coded-mask aperture imaging methods to be effective or when a large field of view is required. Reconstruction of the photon source requires advanced Compton event processing algorithms to determine the exact position of the source. In this study, we introduce a novel method based on a Deep Learning algorithm with a Convolutional Neural Network (CNN) to perform Compton imaging. This algorithm is trained on simulated data and tested on real data acquired with Caliste, a single planar CdTe pixelated detector. We show that performance in terms of source location accuracy is equivalent to state-of-the-art algorithms, while computation time is significantly reduced and sensitivity is improved by a factor of ~5 in the Caliste configuration.

Simulation Study on the Thickness Uniformity of Thin Film Deposited on a Large-Size Substrate in Multi-Source Evaporation System (다중소스 진공증착법에서의 대면적 박막균일도에 관한 전산모사 연구)

  • Kim, Chang-Gyu;Lee, Won-Jong
    • Korean Journal of Materials Research
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    • v.21 no.1
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    • pp.56-66
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    • 2011
  • Multi-source evaporation is one of the methods to improve the thickness uniformity of thin films deposited by evaporation. In this study, a simulator for the relative thickness profile of a thin film deposited by a multi-source evaporation system was developed. Using this simulator, the relative thickness profiles of the evaporated thin films were simulated under various conditions, such as the number and arrangements of sources and source-to-substrate distance. The optimum conditions, in which the thickness uniformity is minimized, and the corresponding efficiency, were obtained. The substrate was a 5th generation substrate (dimensions of 1300 mm ${\times}$ 1100 mm). The number of sources and source-to-substrate distance were varied from 1 to 6 and 0 to the length of the major axis of the substrate (1300 mm), respectively. When the source plane, the area on which sources can be located, is limited to the substrate dimension, the minimum thickness uniformity, obtained when the number of sources is 6, was 3.3%; the corresponding efficiency was 16.6%. When the dimension of the source plane is enlarged two times, the thickness uniformity is remarkably improved while the efficiency is decreased. The minimum thickness uniformity, obtained when the number of sources is 6, was 0.5%; the corresponding efficiency was decreased to 9.1%. The expansion of the source plane brings about not only the improvement of the thickness uniformity, but also a decrement of the efficiency and an enlargement of equipment.

Metric Analysis of Source Code Readability using Regression Analysis (회귀 분석을 사용한 소스 코드 가독성 메트릭 분석)

  • Choi, Sangchul;Kim, Suntae;Lee, Jeong-Hyu;Yoo, Hee-Hyung
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.17 no.6
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    • pp.145-150
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    • 2017
  • Software maintenance accounts for a large portion of the software life cycle cost. In the software maintenance phase, comprehending the legacy source code is inevitable, which takes most of the time. Source code readability is a metric of the extent of code readers' difficulty of code comprehension based on the source code itself. The better the code is readable, the easier it is for code readers to comprehend the source code. This paper proposes novel source code readability metric to quantitative measure the extent of current source code under development, which is more enhanced measurement method than previous research that dichotomously judges whether the source code was readable or not. As an evaluation, we carried out a survey and analyzed them with Regression Analysis to find best parameters of the metric.

Hydroelastic Response Analysis of Very Large Floating Structures Including the Hydrodynamic Forces due to Elastic Motions in Waves (탄성거동에 의한 유체력을 고려한 초대형 부유식 구조물의 유탄성응답 해석)

  • Kim, Chuel-Hyun;Lee, Chang-Ho;Lee, Seung-Chul;Goo, Ja-Sam
    • Journal of Ocean Engineering and Technology
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    • v.20 no.6 s.73
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    • pp.101-107
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    • 2006
  • Recently, with the increase in requirements for marine development, a marine urbanism is being visualized, with more and more huge-scale structures at the scope of the ocean space utilization. In particular, a pontoon-type structure has attracted attention, since The Floating Structures Association of Japan proposed a new concept as the most suitable one of floating airports. The Very Lage Floating Structure (VLFS) is considered a flexible structure, for a quite large length-to-breadth ratio and its geometrical flexibility. The main objective of this study is to makean exact and convenient prediction about the hydro-elastic response on very large offshore structures in waves. The numerical approach for the hydro-elastic responses is based on the combination of the three dimensional source distribution method and the dynamic response analysis method, which assumed a dividing pontoon type structure, as many rigid bodies connected elastic beam elements. The established hydo-elastic theory was applied to the radiation forces caused by motions of a whole structure, formulated using the global coordinate system, which has the origin at the center of the structure. However, in this paper, we took radiation forces, occurred by individual motions of floating bodies, into consideration. The calculated results show good agreement with the experimental and calculated results by Yago.