• Title/Summary/Keyword: ESA

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Calibration and Validation Activities for Earth Observation Mission Future Evolution for GMES

  • LECOMTE Pascal
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.237-240
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    • 2005
  • Calibration and Validation are major element of any space borne Earth Observation Mission. These activities are the major objective of the commissioning phases but routine activities shall be maintained during the whole mission in order to maintain the quality of the product delivered to the users or at least to fully characterise the evolution with time of the product quality. With the launch of ERS-l in 1991, the European Space Agency decided to put in place a group dedicated to these activities, along with the daily monitoring of the product quality for anomaly detection and algorithm evolution. These four elements are all strongly linked together. Today this group is fully responsible for the monitoring of two ESA missions, ERS-2 and Envisat, for a total of 12 instruments of various types, preparing itself for the Earth Explorer series of five. other satellites (Cryosat, Goce, SMOS, ADM-Aeolus, Swarm) and at various levels in past and future Third Party Missions such as Landsat, J-ERS, ALOS and KOMPSAT. The Joint proposal by the European Union and the European Space Agency for a 'Global Monitoring for Environment and Security' project (GMES), triggers a review of the scope of these activities in a much wider framework than the handling of single missions with specific tools, methods and activities. Because of the global objective of this proposal, it is necessary to put in place Multi-Mission Calibration and Validation systems and procedures. GMES Calibration and Validation activities will rely on multi source data access, interoperability, long-term data preservation, and definition standards to facilitate the above objectives. The scope of this presentation is to give an overview of the current Calibration and Validation activities at ESA, and the planned evolution in the context of GMES.

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Effects of Egg Size and Eggshell Conductance on Hatchability Traits of Meat and Layer Breeder Flocks

  • Shafey, Tarek M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.1
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    • pp.1-6
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    • 2002
  • Eggs obtained from 46 and 42 weeks old meat (Hybro) and layer (Leghorn) breeders flocks, respectively were used to examine the effects of genetic type of birds and egg size (small, medium and large) on variables of eggshell characteristics and hatchability traits. The variables measured were egg weight (EW), egg surface area (ESA) and eggshell characteristics (shell conductance (EC), per cent shell (PS), shell thickness (ST), shell volume (SV), shell density (SD) and hatchability traits (per cent hatchability (HP), early dead embryos (ED), late dead embryos (LD), pips with live embryos (PL) and pips with dead embryos (PD)). Genetic type of bird influenced all egg characteristics and HP of eggs. Eggs produced by the small Leghorn bird had lower EW, ESA, EC, ST, SV and HP than those produced by the heavy Hybro bird. The reduction of HP was associated with an increase in the percentage of ED and PL. Egg size influenced all variables measured except ST. Small size eggs had lower EW, ESA and EC and higher PS and SD than those of large eggs. Medium size eggs produced a higher HP when compared with that of large size eggs. The reduction of HP in large eggs was associated with higher percentage of ED, LD and PL. There were significant interactions between the genetic group of birds and egg size on LD and HP. Large egg size of Hybro birds had higher LD and lower HP than those of small size eggs produced by the same flock. However, There was no difference in HP and LD among the different egg sizes produced by Leghorn birds. It was concluded that genetic make up of birds and egg size influence eggshell characteristics and HP. The type of bird (heavy or small) influences the optimum egg size for successful hatching. Attention should be given to the size and eggshell characteristics of eggs of breeders' flocks for achieving maximum HP.

Synthesis and Oxygen Reduction Reaction Characteristics of Multi-Walled Carbon Nanotubes Supported PtxM(1-x) (M = Co, Cu, Ni) Alloy Catalysts for Polymer Electrolyte Membrane Fuel Cell (다중벽 탄소 나노 튜브에 담지한 PtxM(1-x)(M = Co, Cu, Ni) 합금촉매의 제조 및 고분자 전해질 연료전지에서 산소환원 특성)

  • Jung, Dong-Won;Park, Soon;Ahn, Chi-Yeong;Choi, Seong-Ho;Kim, Jun-Bom
    • Korean Journal of Materials Research
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    • v.19 no.12
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    • pp.667-673
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    • 2009
  • The electrocatalytic characteristics of oxygen reduction reaction of the $PtxM_{(1-x)}$ (M = Co, Cu, Ni) supported on multi-walled carbon nanotubes (MWNTs) have been evaluated in a Polymer Electrolyte Membrane Fuel Cell (PEMFC). The $Pt_xM_{(1-x)}$/MWNTs catalysts with a Pt : M atomic ratio of about 3 : 1 were synthesized and applied to the cathode of PEMFC. The crystalline structure and morphology images of the $Pt_xM_{(1-x)}$ particles were characterized by X-ray diffraction and transmission electron microscopy, respectively. The results showed that the crystalline structure of the Pt alloy particles in Pt/MWNTs and $Pt_xM_{(1-x)}$/MWNTs catalysts are seen as FCC, and synthesized $Pt_xM_{(1-x)}$ crystals have lattice parameters smaller than the pure Pt crystal. According to the electrochemical surface area (ESA) calculated with cyclic voltammetry analysis, $Pt_{0.77}Co_{0.23}$/MWNTs catalyst has higher ESA than the other catalysts. The evaluation of a unit cell test using Pt/MWNTs or $Pt_xM_{(1-x)}$/MWNTs as the cathode catalysts demonstrated higher cell performance than did a commercial Pt/C catalyst. Among the MWNTs-supported Pt and $Pt_xM_{(1-x)}$ (M = Co, Cu, Ni) catalysts, the $Pt_{0.77}Co_{0.23}$/MWNTs shows the highest performance with the cathode catalyst of PEMFC because they had the largest ESA.

Detection of Land Subsidence and its Relationship with Land Cover Types using ESA Sentinel Satellites data: A case study of Quetta valley, Pakistan

  • Ahmad, Waqas;Kim, Dongkyun
    • Proceedings of the Korea Water Resources Association Conference
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    • 2018.05a
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    • pp.148-148
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    • 2018
  • Land subsidence caused by excessive groundwater pumping is a serious hydro-geological hazard. The spatial variability in land use, unbalanced groundwater extraction and aquifer characteristics are the key factors which make the problem more difficult to monitor using conventional methods. This study uses the European Space Agency (ESA) Sentinel satellites to investigate and monitor land subsidence varying with different land covers and groundwater use in the arid Quetta valley, Pakistan. The Persistent Scattering Differential Interferometry of Synthetic Aperture Radar (PS-DInSAR) method was used to develop 28 subsidence interferograms of the study area for the period between 16 Oct 2014 and 06 Oct 2016 using ESA's Sentinel-1 SAR data. The uncertainty of DInSAR result is first minimized by removing the dynamic effect caused by atmospheric factors and then filtered using the radar Amplitude Dispersion Index (ADI) to select only the stable pixels. Finally the subsidence maps were generated by spatially interpolating the land subsidence at the stable pixels, the comparison of DInSAR subsidence with GPS readings showed an R 2 of 0.94 and mean absolute error of $5.7{\pm}4.1mm$. The subsidence maps were also analysed for the effect of aquifer type and 4 land covers which were derived from Sentienl-2 multispectral images. The analysis show that during the two year period, the study area experienced highly non-linear land subsidence ranging from 10 to 280 mm. The subsidence at different land covers was significantly different from each other except between the urban and barren land. The barren land and seasonally cultivated area show minor to moderate subsidence while the orchard and urban area with high groundwater extraction rate showed excessive amount of land subsidence. Moreover, the land subsidence and groundwater drawdown was found to be linearly proportional to each other.

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Seismic and Blast Design of Industrial Concrete Structures with Precast Intermediate Shear Wall System (프리캐스트 중간전단벽 시스템이 사용된 콘크리트 산업 시설물의 내진 및 방폭설계)

  • Lee, Won-Jun;Kim, Min-Su;Kim, Seon-hoon;Lee, Deuckhang
    • Journal of the Earthquake Engineering Society of Korea
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    • v.28 no.2
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    • pp.93-101
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    • 2024
  • Code-compliant seismic design should be essentially applied to realize the so-called emulative performance of precast concrete (PC) lateral force-resisting systems, and this study developed simple procedures to design precast industrial buildings with intermediate precast bearing wall systems considering both the effect of seismic and blast loads. Seismic design provisions specified in ACI 318 and ASCE 7 can be directly adopted, for which the so-called 1.5Sy condition is addressed in PC wall-to-wall and wall-to-base connections. Various coupling options were considered and addressed in the seismic design of wall-to-wall connections for the longitudinal and transverse design directions to secure optimized performance and better economic feasibility. On the other hand, two possible methods were adopted in blast analysis: 1) Equivalent static analysis (ESA) based on the simplified graphic method and 2) Incremental dynamic time-history analysis (IDTHA). The ESA is physically austere to use in practice for a typical industrial PC-bearing wall system. Still, it showed an overestimating trend in terms of the lateral deformation. The coupling action between precast wall segments appears to be inevitably required due to substantially large blast loads compared to seismic loads with increasing blast risk levels. Even with the coupled-precast shear walls, the design outcome obtained from the ESA method might not be entirely satisfactory to the drift criteria presented by the ASCE Blast Design Manual. This drawback can be overcome by addressing the IDTHA method, where all the design criteria were fully satisfied with precast shear walls' non-coupling and group-coupling strength, where each individual or grouped shear fence was designed to possess 1.5Sy for the seismic design.

Prediction of Surgical Anesthesia in Medetomidine/Tiletamine/Zolazepam Anesthetized Dogs using Electroencephalography (Medetomidine/Tiletamine/Zolazepam 마취견에서 뇌전도를 이용한 외과마취의 평가)

  • Jang, Hwan-Soo;Kim, Jung-Eun;Lim, Jae-Hyun;Kwon, Young-Sam;Lee, Maan-Gee;Jang, Kwang-Ho
    • Journal of Veterinary Clinics
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    • v.27 no.5
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    • pp.540-545
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    • 2010
  • Changes of electroencephalogram (EEG), mean arterial blood pressure (MAP) and heart rate under surgical anesthesia were investigated in medetomidine (MED) and tiletamine/zolazepam (ZT)-anesthetized dogs. To determine the level of surgical anesthesia, pedal withdrawal reflex was regularly tested after ZT injection. The first time point without pain response was regarded as the beginning of surgical anesthesia (SSA). After SSA, the first time point showing positive pain response was considered the end of surgical anesthesia (ESA). Comparing the control, an additional significant decrease of ${\delta}2$ and ${\alpha}2$ was observed at SSA. Comparing the control, ${\delta}2$ was significantly decreased at ESA. Significant reductions of MAP were observed at pre-ESA and ESA. Heart rate significantly decreased in all stages. These results suggest that ${\delta}2$ band power is a valuable parameter for correlating surgical anesthesia in dogs anesthetized with MED and ZT.

뉴스클릭 - 가짜 예술품 잡아내는 우주방사선탐지기

  • 한국광학기기산업협회
    • The Optical Journal
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    • s.174
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    • pp.30-31
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    • 2019
  • 유럽핵물리입자연구소, CERN은 대형강입자가속기(LHC)가 작동할 때 얻을 수 있는 순간의 장면을 스냅샷으로 남기기 위해 충분한 민감도와 동작 범위를 가진 탐지기가 필요했다. 이렇게 개발된 방사선 탐지기술은 유럽우주국 ESA에 의해 우주로 날아갔다. 그리고 이제는 역사적인 예술품을 분석하고, 위조품을 발견하는 데 사용되고 있다.

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DataBase system construction for the study of radiation hardened electronic devices using pulse radiation (펄스방사선을 이용한 내방사선 연구 DB 구축)

  • Ko, Seong-Gon;Oh, Seung-Chan;Hwang, Young-Gwan;Jeong, Sang-Hun;Lee, Nam-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2012.05a
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    • pp.778-781
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    • 2012
  • The electronic element the damage occurs with radiation being bombed. In order applies in the artificial satellite or the space ship therefore from the within has radiation introspection the use of the radiation electronic element is essential. Transient radiation tests performed for the first time in Korea evaluation data database (DB) was constructed to. Web-based materials in the DB is designed to be able to search and update, and existing foreign (NASA, ESA) for a total of 695 species, including public sources of data has been entered. Search DB than the existing foreign DB is an efficient and practical.

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