• Title/Summary/Keyword: ESA

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Effects of Ethylsalicylic Acid on Growth and Rubisco/Rubisco Activase in Tobacco Plant Cultured under Cadmium Treatment in vitro (카드뮴(Cd) 하에서 기내 배양된 담배의 생장과 Rubisco/Rubisco Activase에 대한 Ethylsalicylic acid의 영향 분석)

  • Roh, Kwang Soo;Cui, Qiu Jie
    • Journal of Life Science
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    • v.24 no.5
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    • pp.558-566
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    • 2014
  • Growth induced by cadmium (Cd) and ethylsalicylic acid (ESA) and the effect of ESA on rubisco/rubisco activase were studied in tobacco. The effect of denaturants on rubisco/rubisco activase was also investigated. In order to determine optimal concentration of ESA for growth of tobacco, tobacco was treated with $10^{-6}$-10 mM. It was found that its growth was the highest at $10^{-4}$ mM ESA. In the experiment using control, Cd treated group, ESA treated group, and Cd and ESA mixture group, ESA alone showed the highest growth and Cd showed the lowest growth. Cd treated group was the lowest in both rubisco/rubisco activase content and activity. ESA reduced the rubisco/rubisco activase content, but increased their activity. The activity of rubisco was inhibited by treating L-cysteine, urea, thiourea, ${\beta}$-mercaptoethanol, and EDTA other than guanidine-HCl in control group. L-cysteine, urea, thiourea, and guanidine-HCl treatments showed no change, but ${\beta}$-mercaptoethanol and EDTA increased rubisco activase activity. In conclusion, ESA inhibited the content of rubisco and promoted its activity, whereas promoted the content of rubisco activase and inhibited its activity. In addition, the content and activity of rubisco and rubisco activase inhibited by Cd were recovered by ESA. The activity of rubisco and rubisco activase by Cd and ESA was inhibited by the denaturant and the recovery of ESA inhibited by Cd was lost by the denaturant.

아리안 5호의 추적

  • 한국항공우주산업진흥협회
    • Aerospace Industry
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    • v.42
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    • pp.56-59
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    • 1996
  • 유럽은 유럽 13개국을 정식 가맹국으로 하고 캐나다, 핀랜드를 준가맹국으로 하는 유럽우주기구(ESA)를 조직하여 운영하고 있다. 이것은 미국, 러시아, 일본 중국등과의 우주 이용 경쟁에서 유럽이 공동체로 뭉쳐 대응하려는 것이다. ESA는 ESA각료급 이사회(ESA-MC)의 결정에 따라 아리온 로켓을 개발하고 있다.

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The PRF Design Method Considering Beamwidth Interference Using ESA Radar (ESA 레이다의 빔폭 특성을 고려한 적정 PRF 설계 기법)

  • Park, Joon-Yong
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.30 no.6
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    • pp.498-506
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    • 2019
  • In this paper, we propose a PRF design method to improve the performance of the ESA radar, by excluding the interference from an improper PRF. Like the conventional method, the proposed method also considers the interference between the transmitted signal and the nadir signal, but additionally analyzes the relationship between the interference and the signal beamwidth. The simulation results show that the proposed method quantitatively and qualitatively excluded interference from the PRF and additionally dealt with the beamwidth broadening effect of an ESA radar.

An Analysis of Agile Methodologies' Trends and Introduction cases of the Methodologies at the ESA Ground Segment Software Development (애자일 방법론의 동향 및 ESA 지상국 소프트웨어 개발 분야의 도입사례 분석)

  • Seo, Seok-Bae;Kang, Ji-Hoon
    • Aerospace Engineering and Technology
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    • v.11 no.1
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    • pp.111-117
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    • 2012
  • Agile is a software development methodology which was established for four objectives; people, collaboration, responsiveness, and working software. Thus the Agile methodologies have been applied not only software development fields but also various special areas of technology. ESA (European Space Agency) adopt several Agile methodologies, including Scrum as the key technique, for the software development of ground segment. This article analyzes trends of Agile methodologies and introduction cases of the methodologies for ESA's ground segment software development.

Using Echolocation Search Algorithm (ESA) for truss size optimization

  • Nobahari, Mehdi;Ghabdiyan, Nafise
    • Steel and Composite Structures
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    • v.42 no.6
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    • pp.855-864
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    • 2022
  • Due to limited resources, and increasing speed of development, the optimal use of available resources has become the most important challenge of human societies. In the last few decades, many researchers have focused their research on solving various optimization problems, providing new optimization methods, and improving the performance of existing optimization methods. Echolocation Search Algorithm (ESA) is an evolutionary optimization algorithm that is based on mimicking the mechanism of the animals such as bats, dolphins, oilbirds, etc in food finding to solve optimization problems. In this paper, the ability of ESA for solving truss size optimization problems with continuous variables is investigated. To examine the efficiency of ESA, three benchmark examples are considered. The numerical results exhibit the effectiveness of ESA for solving truss optimization problems.

ESA Earth Observation Programmes and International Cooperation in the frame of Third Party Missions

  • Hoersch B.;Laur H.;Kohlhammer G.
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.598-600
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    • 2004
  • In Europe most Earth Observation (EO) data users rely on several EO missions, both to increase sustainability of their service and to widen the range of observation parameters. In addition to its own missions such as ERS 1 &2, ENVISAT and the Earth Explorers, ESA therefore offers access to the scientific and applications community to so-called 'Third Party Missions'. Third Party (TP) missions are complementing the observations of ESA missions, are used to prepare for future ESA missions including cross-calibration and create synergy to favor a wider use of EO data within ESA Member States.

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세계의 항공우주기구(2) - ESA

  • Korea Aerospace Industries Association
    • Aerospace Industry
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    • s.95
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    • pp.38-41
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    • 2007
  • 세계 각국이 여전히 치열하게 우주개발을 진행하고 있는 가운데, 미국에 NASA가 있다면 유럽에는 유럽우주기구 ESA가 있다. 이번호는 유럽우주기구 ESA를 살펴본다.

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Stimulation of Molting and Ovarian Maturation by Methyl Farnesoate in the Pacific White Shrimp Litopenaeus vannamei (Boone, 1931)

  • Alnawafleh, Tariq;Kim, Bo-Kwang;Kang, Hye-Eun;Yoon, Tae-Ho;Kim, Hyun-Woo
    • Fisheries and Aquatic Sciences
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    • v.17 no.1
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    • pp.115-121
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    • 2014
  • Eyestalk ablation (ESA) is commonly used in aquaculture to stimulate ovarian maturation in crustaceans, and methyl farnesoate (MF) affects crustacean molting and reproduction. To investigate the physiological effects of ESA and MF treatments on the shrimp Litopenaeus vannamei, we compared the effects of single eyestalk removal and MF injections. The ESA group had the lowest survival rate (50%), and individuals in the $0.1{\mu}g$ and $1.0{\mu}g$ MF-treated groups had survival rates of 80 and 73.3%, respectively. Conversely, molting numbers were highest in the ESA group, and similar to those of the 1.0-${\mu}g$ MF group. To investigate shrimp growth, we measured body weight during the experimental period and found that individuals in the ESA and $1.0{\mu}g$ MF groups showed significant increases in body weight. Furthermore, to investigate the effects of ESA and MF treatments on gonadal maturation, the gonad somatic index (GSI) was calculated after the experiment. All treated groups (ESA and MF) had higher GSI values than the control group, but the ESA and $1.0{\mu}g$ MF groups were not significantly different. Using histological ovary analysis, we determined that all treated groups showed indications of the previtellogenic stage, unlike the control group (immature stage). These results suggest that the high-MF-concentration treatment produced effects similar to those of ESA with respect to molting number, growth, and ovarian maturation.

Centrifuge Model Tests on the Pullout Capacity of Embedded Suction Anchor without Flanges in Sand layer (모래지반에 매입된 날개없는 석션앵커의 인발력에 대한 원심모형실험)

  • Kim, Kyoung-O;Kim, You-Seok;Ko, Boo-Hyun
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.10a
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    • pp.517-520
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    • 2005
  • The embedded suction anchor(ESA) is and anchor that is driven by a suction pile. The cross-sectional shape of the ESA anchor is circle. Its diameter is the same as that of the suction pile that is used to drive it into the seafloor. For the installation, the anchor is attached to the tip of the suction pile and then driven as a unit with the pile by and applied suction pressure. Once the ESA anchor reaches the desired depth, the pile is retrieved by applying a positive pressure. Finally, only the ESA anchor remains in the soil layer. This paper presents the results of centrifuge model tests to investigate ESA pullout capacity. The main parameters that have effects on the pullout capacity of ESA may include g-level, embedded depth, direction of loading, and loading point. The results of tests show that the pullout loading capacities increase as the loading point shift toward the tip of the anchors for a given loading direction. They also indicate that the loading point associated with the maximum pullout loading capacity is located at approximately 67 percent of the anchor length from the top for the horizontal load.

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Bloating Mechanism of Lightweight Aggregate with the Size

  • Lee, Ki Gang
    • Journal of the Korean Ceramic Society
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    • v.53 no.2
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    • pp.241-245
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    • 2016
  • The purpose of this study was to investigate the bloating mechanism of artificial lightweight aggregates with different sizes (ESA, effective surface area). Aggregates were produced using hard clay, stone sludge, and a bloating agent in order to observe the effect of the gradation of the artificial lightweight aggregates. Kerosene and amorphous carbon were used as bloating agent. The particle size of the produced aggregate ranged from 3 mm to 9 mm. With regard to the amount of bloating agent to be used, 2 ~ 6 parts by weight were used. The specific gravity, absorption rate, and the type of aggregates produced by rapid sintering at $1075{\sim}1200^{\circ}C$ were determined. Microstructures were observed. When ESA had a value of 1 or below, kerosene, which has a high burning rate, was found to be advantageous for use as a bloating agent. When ESA had a value of 1 or above, carbon, which has a relatively low burning rate was found to be an advantageous bloating agent. It is thought that kerosene is more advantageous, as ESA decreases, for the production of aggregates having low water absorption rate.