• Title/Summary/Keyword: U.J.S.

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Battery Related R&D in the U.S.

  • Brodd Ralph J.
    • 한국전기화학회:학술대회논문집
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    • 한국전기화학회 1999년도 제3회 총회 및 추계학술발표회
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    • pp.9-9
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    • 1999
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POST-IRRADIATION ANALYSES OF U-MO DISPERSION FUEL RODS OF KOMO TESTS AT HANARO

  • Ryu, H.J.;Park, J.M.;Jeong, Y.J.;Lee, K.H.;Lee, Y.S.;Kim, C.K.;Kim, Y.S.
    • Nuclear Engineering and Technology
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    • 제45권7호
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    • pp.847-858
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    • 2013
  • Since 2001, a series of five irradiation test campaigns for atomized U-Mo dispersion fuel rods, KOMO-1, -2, -3, -4, and -5, has been conducted at HANARO (Korea) in order to develop high performance low enriched uranium dispersion fuel for research reactors. The KOMO irradiation tests provided valuable information on the irradiation behavior of U-Mo fuel that results from the distinct fuel design and irradiation conditions of the rod fuel for HANARO. Full size U-Mo dispersion fuel rods of 4-5 $g-U/cm^3$ were irradiated at a maximum linear power of approximately 105 kW/m up to 85% of the initial U-235 depletion burnup without breakaway swelling or fuel cladding failure. Electron probe microanalyses of the irradiated samples showed localized distribution of the silicon that was added in the matrix during fuel fabrication and confirmed its beneficial effect on interaction layer growth during irradiation. The modifications of U-Mo fuel particles by the addition of a ternary alloying element (Ti or Zr), additional protective coatings (silicide or nitride), and the use of larger fuel particles resulted in significantly reduced interaction layers between fuel particles and Al.

CONVOLUTION SUMS OF ODD AND EVEN DIVISOR FUNCTIONS

  • Kim, Daeyeoul
    • 호남수학학술지
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    • 제35권3호
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    • pp.445-506
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    • 2013
  • Let ${\sigma}_s(N)$ denote the sum of the s-th power of the positive divisors of N and ${\sigma}_{s,r}(N;m)={\sum_{d{\mid}N\\d{\equiv}r\;mod\;m}}\;d^s$ with $N,m,r,s,d{\in}\mathbb{Z}$, $d,s$ > 0 and $r{\geq}0$. In a celebrated paper [33], Ramanuja proved $\sum_{k=1}^{N-1}{\sigma}_1(k){\sigma}_1(N-k)=\frac{5}{12}{\sigma}_3(N)+\frac{1}{12}{\sigma}_1(N)-\frac{6}{12}N{\sigma}_1(N)$ using elementary arguments. The coefficients' relation in this identity ($\frac{5}{12}+\frac{1}{12}-\frac{6}{12}=0$) motivated us to write this article. In this article, we found the convolution sums $\sum_{k<N/m}{\sigma}_{1,i}(dk;2){\sigma}_{1,j}(N-mk;2)$ for odd and even divisor functions with $i,j=0,1$, $m=1,2,4$, and $d{\mid}m$. If N is an odd positive integer, $i,j=0,1$, $m=1,2,4$, $s=0,1,2$, and $d{\mid}m{\mid}2^s$, then there exist $u,a,b,c{\in}\mathbb{Z}$ satisfying $\sum_{k& lt;2^sN/m}{\sigma}_{1,i}(dk;2){\sigma}_{1,j}(2^sN-mk;2)=\frac{1}{u}[a{\sigma}_3(N)+bN{\sigma}_1(N)+c{\sigma}_1(N)]$ with $a+b+c=0$ and ($u,a,b,c$) = 1(Theorem 1.1). We also give an elementary problem (O) and solve special cases of them in (O) (Corollary 3.27).

안전한 유비쿼터스 환경을 위한 Fusion Security Framework 요구사항 분석 (Analysis of Fusion Security Framework for Secure Ubiquitous Enviro nment)

  • 김광식;최병철;서동일;장종수;손승원
    • 전자통신동향분석
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    • 제19권5호통권89호
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    • pp.95-106
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    • 2004
  • 유비쿼터스 네트워크는 언제, 어디서나, 어떤 기기로도 고품질의 다양한 유비쿼터스 서비스를 가능하게할 것이다. 디지털 홈, 전자정부, e-비즈니스 서비스를 제공하기 위해서 통신서비스, 방송서비스, 인터넷서비스가 BcN을 중심으로 컨버전스 된다고 볼 수 있다. 안전한 유비쿼터스 환경을 위해서는 새롭게 제안하는 fusion security framework의 조기정착이 필수적이며, 이를 위한 기술적 측면의 정보보호와 법적/제도적 측면의 정보보호를 알아보고, 향후의 유비쿼터스 정보보호에 대한 정책적 방향을 제안하고자 한다. 특히, 기술적인 측면에서의 국가 정책방향은 크게 인터넷 안전 대응체계 강화를 위한 u-secureKorea, 깨끗한 사이버 환경 구현을 위한 u-clean Korea, 개인정보보호 환경 구현을 위한 u-privacyKorea의 3가지 분야로 구분할 수 있으며, 3개 분야별로 BcN 인프라 보호기술 개발, 정보침해 방지기술개발, 개인정보 보호기술 개발을 추진하여야 하는 당위성을 제시하고자 한다.

ZCS공진형 컨버터를 적용한 고반복 대출력 펄스형 Nd:YAG 레이저 전원장치 개발 (Development of high repetition rate and high power pulsed Nd:YAG laser power supply using ZCS resonant converter)

  • 조기연;김은수;변영복;김희제;박점문;이현우
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1996년도 하계학술대회 논문집 A
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    • pp.514-517
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    • 1996
  • Zero current switching(ZCS) series resonant converter is used to control laser power density in a pulsed Nd:YAG laser power supply. The high power and high repetition rate paused Nd:YAG laser is designed and fabricated to control current pulse width and pulse repetition rate in the double elliptical laser oscillator. In order to find out operational characteristics of pulsed Nd:YAG laser, the electrical properties of driving power supply and laser output power are investigated and experimented by changing of the current pulse width from 200uS to 350uS(step 50uS) and pulse repetition rate range of 500pps(pulse per second) to 1150pps. From that result, we obtaind maximum efficiency of 1.83% and maximum laser output or 220W at the condition of 350 uS and 1150pps with one Nd:YAG rod), and obtained that of more than 400W with two laser head connecting series.

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