• Title/Summary/Keyword: Nea

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Hot Firing Test of a Quadrature NEA SSD9103S1 Configuration

  • Ja-Chun, Koo;Hee-Sung, Park;Max, Guba
    • International Journal of Aerospace System Engineering
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    • v.9 no.2
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    • pp.1-9
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    • 2022
  • The NEA release mechanism is used to provide restraint and release functions with low shock for critical deployment operations on solar arrays after launch. The GK3 solar array consists of 2 wings and 6 hold down points per panel. The NEA SSD9103S1 is a part of the GK3 solar array hold-down and release mechanism. Each NEA unit is equipped with two Z-diodes which provide power to a NEA unit connected in series after actuation of the fuse wire. This paper presents the hot firing test results of a quadrature NEA SSD9103S1 configuration. One output powers a maximum of 4 NEA SSD9103S1 units simultaneously. The necessary actuation pulse duration has been determined to meet margin requirement for thermal energy of minimum 4. Actuation thermal energy difference is about 6.6% between each half of two fired serial NEAs. Thermal energy margin at worst case is minimum 5.9 in case of an actuation pulse duration of 500 ms. Two series Zener impedance depend on current applied has been characterized by an additional actuation after all fuse wires are open circuit. Total number of actuation commands to the GK3 NEA unit reduce drastically from 24 in case of single NEA configuration down to 8 in case of parallel and quadrature NEA configurations. It can be accommodated by the existing HP2U Pyro design without any impact.

Selective Encryption and Decryption Method for IVC Codec (IVC 코덱을 위한 선택적 암호화 및 복호화 방법)

  • Lee, Min Ku;Kim, Kyu-Tae;Jang, Euee S.
    • Journal of Broadcast Engineering
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    • v.25 no.6
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    • pp.1013-1016
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    • 2020
  • This paper presents a selective encryption and decryption method exploiting the start code of the IVC bitstream. The existing encryption methods for video are largely classified into two methods: Naive Encryption Algorithm (NEA) and Selective Encryption Algorithm (SEA). Since NEA encrypts the entire bitstream, it has the advantage of high security but has the disadvantage of high computational complexity. SEA improves the encryption and decryption speed compared to NEA by encrypting a part of the bitstream, but there is a problem that security is relatively low. The proposed method improves the encryption and decryption speed and the security of the existing SEA by using the start code of the IVC bitstream. As a result of the experiment, the proposed method reduces the encryption speed by 96% and the decryption speed by 98% on average compared to the NEA.

Growth and Energy Budgets of Greenling Hexagrammos otakii Larvae and Juveniles Reared on Different Diets and Temperatures (쥐노래미(Hexagrammos otakii)자치어의 먹이와 수온에 따른 성장 및 에너지 수지)

  • Park, Jun Woo;Kwon, O-Nam;Park, Kie-Young
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.3
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    • pp.287-295
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    • 2013
  • The growth, respiration, ingestion, and ecological efficiencies of Hexagrammos otakii larvae and juveniles reared on different diets and temperatures were estimated. A factorial experiment using two diets [non-enriched hatched Artemia nauplii (NEA) and enriched Artemia nauplii (EA)] crossed with two temperatures [natural seawater temperature (NT, $5.1-8.5^{\circ}C$) and heated seawater (HT, $13{\pm}0.5^{\circ}C$)] was conducted to investigate growth and energy budgets of Hexagrammos otakii larvae and juveniles. The energy used by larvae and juveniles for 6 weeks was calculated using data on ingestion, growth, respiration, excretion, and egestion. In the NT trials, the energy used for growth by larvae and juveniles was 0.121 and 0.129 Kcal in the NEA and EA treatments, respectively. Assimilation efficiency at NT were 78.0% and 80.2% in the NEA and EA trials, respectively. Gross growth efficiency ($K_1$) were 60.5% and 62.3% and net growth efficiency ($K_2$) was 77.56% and 77.71% in the NEA and EA trials, respectively. In the HT trials, the energy used for growth by juveniles was 0.189 and 0.212 Kcal in the NEA and EA trials, respectively. Assimilation efficiency at HT was 86.4% and 95.1% in the NEA and EA trials, respectively. Values of $K_1$ and $K_2$ at HT were 69.5% and 80.43%, respectively, in the NEA trials, and 73.9% and 77.66%, respectively, in the EA trials. These results suggest that enriched Artemia nauplii and higher temperatures ($13{\pm}0.5^{\circ}C$) are effective for rearing larvae and juveniles of H. otakii.

American Culture at the Crossroad : Debates over NEA(National Endowments for the Arts) (미국 문화, 그 기로에 서서 - NEA(국립예술진흥기금)를 둘러싼 논쟁 중심으로)

  • Kim, Jin-A
    • The Journal of Art Theory & Practice
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    • no.4
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    • pp.33-56
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    • 2006
  • The cultural debates between conservatives and liberals at the end of the 1980s and in the early 1990s were termed as "culture wars." The "culture wars" involved a diverse range of controversial issues, such as the introduction of multicultural curricula in educational institutions, prayers in schools, whether to allow gays to serve openly in the military, and whether abortion should be permitted. The most heated debates of the "culture wars" regarding art raged over the NEA and the question of whether Andres Serrano's works should have been publicly funded, in addition to the exhibition "Robert Mapplethorpe: The Perfect Moment" which were charged as projecting "obscene" or "blasphemous" images. This paper examines the development of culture wars in art and focuses on several issues invoked by the NEA debates. However, it is not a detailed chronological investigation. Rather it pays attention to the several phases of the debates, analyzing and criticizing the clashes of the political and esthetical points of views between conservatives and liberals. How could NEA funding, a mere fraction of the federal budget, have become so critical for both sides(conservative and liberal), for politicians and artists' groups, and for academics and the general public? The art community was astounded by this chain of events; artists personally reviled, exhibitions withdrawn and under attack, the NEA budget threatened, all because of a few images. For conservative politicians, the NEA debate was not only a battle over the public funding of art, but a war over a larger social agenda, a war for "American values and cultures"based on the family, Christianity, the English language, and patriarchy. Conservative politicians argued the question was not one of "censorship" but of "sponsorship," since the NEA charter committed it to "helping museums better serve the citizens of the United States."Liberals and art communities argued that the attempt to restrict NEA funding violated the First Amendment rights of artists, namely "free speeches." "No matter how divided individuals are on matters of taste," Arthur C. Danto wrote, "freedom is in the interest of every citizen." The interesting phase is that both sides are actually borrowing one another's point of view when they are accompanied by art criticism. Kramer, representative of conservative art critic, objected the invasion of political contents or values in art, and struggled to keep art's own realm by promoting pure aesthetic values such as quality and beauty. But, when he talked about Mapplethorpe's works, he advocated political and ethical values. By contrast, art experts who argued for Mapplethorpe's works in the Cincinnati trial defended his work, ironically by ignoring its manifest sexual metaphor or content although they believed that the issues of AIDS and homosexuality in his work were to be freely expressed in the art form. They adopted a formalistic approach, for example, by comparing a child nude with putti, a traditional child-angel icon. For a while, NEA debates made art institutions, whether consciously or unconsciously, exert self-censorship, yet at the same time they were also producing positive aspects. To the majority of people, art was still regarded as belonging to the pure aesthetic realm away from political, economical, and social ones. These debates, however, were expanding the very perspective on the notion of what is art and of how art is produced, raising questions on art appreciation, representation, and power. The interesting fact remains: had the works not been swiped in NEA debates, could the Serrano's or Mapplethorpe's images gain the extent of power and acceptance that it has today?

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OECD/NEA STUDY ON THE ECONOMICS AND MARKET OF SMALL REACTORS

  • Lokhov, Alexey;Cameron, Ron;Sozoniuk, Vladislav
    • Nuclear Engineering and Technology
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    • v.45 no.6
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    • pp.701-706
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    • 2013
  • According to the OECD/NEA estimates, nuclear power plants (NPPs), whether with a large reactor or with small modular reactors (SMRs), are competitive with many other electricity generation technologies in a significant number of cases, one of the exceptions being natural gas in the USA with the current level of prices. However, SMRs have particular features and requirements setting conditions for their deployment. This paper presents the preliminary analysis by OECD/NEA of the economics, opportunities, and market for small nuclear reactors.

자연방사선의 변동범위내 - 체르노빌사고영향에 관한 OECD/NEA 보고서 -

  • 한국원자력산업회의
    • Nuclear industry
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    • v.8 no.7 s.65
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    • pp.93-95
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    • 1988
  • 소련 체르노빌원전에서 사고가 발생한지 2년이 넘었다. 우리나라에서는 방사성물질 강하 등의 영향이 거의 없었으나, 지리적으로 가까운 유럽에서는 사고 당시 심각한 영향을 받은 국가가 있었다고 한다. 경제협력개발기구/원자력기관(OECD/NEA)이 금년 1월 사고영향에 관한 보고서를 발표하였다. 다음은 방사선에 의한 영향을 중심으로 한 동 보고서의 개요이다.

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우라늄 자원의 수요전망 - OECD/NEA$\cdot$IAEA 보고서에서 -

  • 한국원자력산업회의
    • Nuclear industry
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    • v.8 no.9 s.67
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    • pp.78-80
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    • 1988
  • 경제협력개발기구$\cdot$원자력기관(OECD/NEA)과 국제원자력기구(IAEA)는 ${\ulcorner}$우라늄자원-생산과 수급${\lrcorner}$에 관한 보고서를 발표하였다. 중앙경제계획권이외(WOCA)의 국가에서는 전년도에 이어 계속해서 우라늄의 생산이 수요를 하회했음이 밝혀졌다. 다음은 동 보고서의 수급전망을 소개한 것이다.

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Color Strength and Fastness of Pigment Ink with Various Binder Monomer Compositions (바인더의 공중합체 조성에 따른 안료잉크의 발색성 및 견뢰도 연구)

  • Kwon, Woong;Lee, Minkyu;Jeong, Euigyung;Bae, Jin-Seok
    • Textile Coloration and Finishing
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    • v.30 no.4
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    • pp.256-263
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    • 2018
  • The binder polymers for digital textile printing(DTP) pigment inks were prepared using miniemulsion polymerization with various monomer compositions to study effects of monomer compositions on particle size distribution, average molecular weight, Tg, and color strength and rubbing fastness of the dyed fabrics with the prepared binder based pigment ink. The monomers used were MMA(Methyl methacrylate), BA(Butyl acrylate), MAA(Methacrylic acid), NMA(N-methylol acrylamide), NEA(N-ethylol acrylamide) and the ratios of the monomers were changed. The particle size was the smallest with 136nm when the MMA to BA weight ratio was 4:16 and the largest with 290nm when the MMA, BA, MAA, NEA ratio was 2.5:17:0.25:0.25. However, the glass transition temperature was lowest with $-41.90^{\circ}C$ and the color strength and rubbing fastness of the resulting sample were the best when the MMA, BA, MAA, NEA ratio was used. This suggested that the introduction of the NEA monomer to the binder polymer for the pigment ink could be an efficient way to enhance the rubbing fastness of the DTP pigment inks present.