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Sample records for bartkut leonidas sakalauskas

  1. Athens 2004 Team Leaders' Attitudes toward the Educational Multimedia Application "Leonidas"

    ERIC Educational Resources Information Center

    Vernadakis, Nikolaos; Giannousi, Maria; Derri, Vassiliki; Kellis, Iraklis; Kioumourtzoglou, Efthimis

    2010-01-01

    The purpose of this study was to adapt the questionnaire Multimedia Attitude Survey (MAS; Garcia, 2001) to the Greek population in order to evaluate the educational multimedia application "Leonidas" considering the attitudes of ATHENS 2004 team leaders. In addition, the differences among the sex were also investigated. Participants were 232 team…

  2. Swelling of U(Mo)–Al(Si) dispersion fuel under irradiation – Non-destructive analyses of the LEONIDAS E-FUTURE plates

    SciTech Connect

    S. Van den Berghe; Y. Parthoens; F. Charollais; Y. S. Kim; A. Leenaers; E. Koonen; V. Kuzminov; P. Lemoine; C. Jarousse; H. Guyon; D. Wachs; D. Keiser, Jr.; A. Robinson; J. Stevens; G. Hofman

    2012-11-01

    In the framework of the elimination of High-Enriched Uranium (HEU) from the civil circuit, the search for an appropriate fuel to replace the high-enriched research reactor fuel in those reactors that currently still require it for their operation has led to the development of a U–7 wt.%Mo alloy based dispersion fuel with an Al–Si matrix. The European LEONIDAS program, joining SCK-CEN, ILL, CEA and AREVA-CERCA, is aimed at the qualification of such a fuel for the use in high power conditions. The first experiment of the program, designated E-FUTURE, was performed to select the appropriate matrix Si concentration and fuel plate post-production heat treatment parameters for further qualification. It consisted of the irradiation of four distinct (4% and 6% Si, 3 different heat treatments) full size, flat fuel plates in the BR2 reactor. The irradiation conditions were relatively severe: 470 W/cm2 peak BOL power, with an approximate 70% 235U peak burnup.

  3. Swelling of U(Mo)-Al(Si) dispersion fuel under irradiation - Non-destructive analyses of the LEONIDAS E-FUTURE plates

    NASA Astrophysics Data System (ADS)

    Van den Berghe, S.; Parthoens, Y.; Charollais, F.; Kim, Y. S.; Leenaers, A.; Koonen, E.; Kuzminov, V.; Lemoine, P.; Jarousse, C.; Guyon, H.; Wachs, D.; Keiser, D., Jr.; Robinson, A.; Stevens, J.; Hofman, G.

    2012-11-01

    In the framework of the elimination of High-Enriched Uranium (HEU) from the civil circuit, the search for an appropriate fuel to replace the high-enriched research reactor fuel in those reactors that currently still require it for their operation has led to the development of a U-7 wt.%Mo alloy based dispersion fuel with an Al-Si matrix. The European LEONIDAS program, joining SCK•CEN, ILL, CEA and AREVA-CERCA, is aimed at the qualification of such a fuel for the use in high power conditions. The first experiment of the program, designated E-FUTURE, was performed to select the appropriate matrix Si concentration and fuel plate post-production heat treatment parameters for further qualification. It consisted of the irradiation of four distinct (4% and 6% Si, 3 different heat treatments) full size, flat fuel plates in the BR2 reactor. The irradiation conditions were relatively severe: 470 W/cm2 peak BOL power, with a ˜70% 235U peak burnup.

  4. Performance evaluation of the R6R018 fuel plate using PLATE code

    SciTech Connect

    Pavel G. Medvedev; Hakan Ozaltun

    2010-03-01

    The paper presents results of performance evaluation of the R6R018 fuel plate using PLATE code. R6R018 is a U-7Mo dispersion type mini-plate with Al-3.5Si matrix irradiated in the RERTR-9B experiment. The design of this plate is prototypical of the planned LEONIDAS irradiation test. Therefore, a detailed performance analysis of this plate is important to confirm acceptable behavior in pile, and to provide baseline and justification for further analysis and testing. Specific results presented in the paper include fuel temperature history, growth of the interaction layer between the U-Mo and the matrix, swelling, growth of the corrosion layer, and degradation of thermal conductivity. The methodology of the analysis will be discussed including the newly developed capability to account for the formation of the interaction layer during fuel fabrication.

  5. Near real-time tracking of dynamic properties for standalone structural health monitoring systems

    NASA Astrophysics Data System (ADS)

    Rainieri, C.; Fabbrocino, G.; Cosenza, E.

    2011-11-01

    Automated modal parameter identification of civil engineering structures has been analyzed in a previous paper. An original algorithm, named LEONIDA, working in frequency domain, has been presented and a number of test cases have been discussed in order to point out advantages and drawbacks. It has been demonstrated that LEONIDA represents a promising and reliable tool, in particular for modal testing. Conversely, integration of such a procedure into a fully automated structural health monitoring (SHM) system has shown that it can be used as modal information engine, but length of record durations, amount of computational burden and response time lead to recognize that serious drawbacks and limitations exist for a class of applications, such as continuous monitoring of structures in seismically prone areas. In fact, a fast assessment of relevant structure health conditions in the early post-earthquake phase is becoming of interest in different European areas. In such a context, the statistical treatment of measured dynamic properties could be certainly useful, but it requires the collection of an extensive amount of local and global data in a short time. As a consequence, availability of reliable, robust and fairly fast data processing procedures for modal tracking is fundamental whenever really effective and useful SHM systems are adopted to support civil protection activities during seismic sequences. This applies mainly to strategic structures, whose health conditions must be rapidly assessed after any seismic event, in order to securely manage rescue operations. In the present paper, the main issues related to a fast, robust and reliable modal tracking for emergency management are outlined. Then, an automated modal tracking strategy for SHM applications in earthquake prone regions is described. It is based on the knowledge of the experimental mode shapes and a revised concept of spatial filtering. Results of sample applications of the proposed procedure refer

  6. Quantum Femtosecond Magnetism: Phase Transition in Step with Light in a Strongly Correlated Manganese Oxide

    NASA Astrophysics Data System (ADS)

    Wang, Jigang

    2014-03-01

    Research of non-equilibrium phase transitions of strongly correlated electrons is built around addressing an outstanding challenge: how to achieve ultrafast manipulation of competing magnetic/electronic phases and reveal thermodynamically hidden orders at highly non-thermal, femtosecond timescales? Recently we reveal a new paradigm called quantum femtosecond magnetism-photoinduced femtosecond magnetic phase transitions driven by quantum spin flip fluctuations correlated with laser-excited inter-atomic coherent bonding. We demonstrate an antiferromagnetic (AFM) to ferromagnetic (FM) switching during about 100 fs laser pulses in a colossal magneto-resistive manganese oxide. Our results show a huge photoinduced femtosecond spin generation, measured by magnetic circular dichroism, with photo-excitation threshold behavior absent in the picosecond dynamics. This reveals an initial quantum coherent regime of magnetism, while the optical polarization/coherence still interacts with the spins to initiate local FM correlations that compete with the surrounding AFM matrix. Our results thus provide a framework that explores quantum non-equilibrium kinetics to drive phase transitions between exotic ground states in strongly correlated elecrons, and raise fundamental questions regarding some accepted rules, such as free energy and adiabatic potential surface. This work is in collaboration with Tianqi Li, Aaron Patz, Leonidas Mouchliadis, Jiaqiang Yan, Thomas A. Lograsso, Ilias E. Perakis. This work was supported by the National Science Foundation (contract no. DMR-1055352). Material synthesis at the Ames Laboratory was supported by the US Department of Energy-Basic Energy Sciences (contract no. DE-AC02-7CH11358).

  7. Taxonomic notes on the genus Auranus (Opiliones, Laniatores, Stygnidae), with description of two new species.

    PubMed

    Colmenares, Pío A; Porto, Willians; Tourinho, Ana Lúcia

    2016-01-01

    Among the Amazonian families of harvestmen the members of Stygnidae are better known due to the recent revision of the family and efforts of specialists describing new taxa in the last few years. Species of Amazonian genus Auranus Mello-Leitão, 1941, have been collected in several inventories that were carried out in different locations of the Amazon basin. In this paper we provide a new diagnosis for Auranus, and the description of two new species: Auranus leonidas sp. nov. and Auranus xerxes sp. nov. from the Brazilian states of Roraima and Amazonas, respectively. We also offer complementary genital descriptions of Auranus hehu Pinto-da-Rocha & Tourinho 2012, Auranus parvus Mello-Leitão, 1941, and Auranus tepui Pinto-da-Rocha & Tourinho 2012. Five species are recognized in Auranus, including the two new species described in this paper. The lamina parva modified into a calyx is proposed as putative synapomorphy for the genus Auranus. Therefore, A. hoeferscovitorum, which does not possess this character, is removed from Auranus. Instead we propose for it the new combination Verrucastygnus hoeferscovitorum comb. nov. We also provide a key to the males of Auranus, and a map with the distribution for all species examined in this work. PMID:27394622

  8. Outcomes From AAS Hack Day at the 227th AAS Meeting

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-01-01

    paper, Ruth is seeking contributions of one-minute audio recordings.RadioFree LST: Radio observers dont care when the Sun is up, but they do care if their astronomical objects of interest are above the horizon. Demitri Muna (Ohio State) and Amanda Kepley (NRAO) created a calculator which uses local sidereal time (LST) to determine when sources rise and set based on the position of the observatory and the coordinates of the target..@demitrimuna @aakepley are creating a LST calculator for radio telescopes. #radiofreelst #hackaas pic.twitter.com/TEAdYe3hvi astrobites (@astrobites) January 8, 2016Hidden Killer Detective: The Kepler spacecraft has enabled many discoveries related to exoplanets and stars. But now that K2 is observing in the ecliptic plane, it should also find asteroids. Geert Barentsen (NASA Ames), Tom Barclay (NASA Ames), Meg Schwamb (ASIAA), and Brooke Simmons (UC San Diego) created a new crowd-sourced Zooniverse project so anyone can help search for moving objects that may be asteroids.Expanding Astronomy on Tap: This casual science pub night, started in 2013, is now a regular event in seven cities worldwide. Jeff Silverman (UT Austin) created a Launch Manifesto and guide for bringing Astronomy on Tap to your own city. If youre interested, fill out their survey to get more information.The Arceli Project: Arceli is publishing online astronomy content. A team led by ScienceBetter and Kelle Cruz (CUNY) including Daina Bouquin (Harvard CfA), Aram Zucker-Scharff, Lars Holm Nielsen (CERN), Jonathan Sick (LSST), Chris Erdmann (Harvard CfA), and Meredith Rawls (NMSU) worked on getting each component of Arceli to talk to the others. Eventually, Arceli will accept submissions of informal scholarly contentlike blog postswhich will become archived and citable just like traditional papers.Special Dark: Leonidas Moustakas (JPL/Caltech) and Tonima Ananna (Yale) hosted a special session at this years AAS meeting all about dark matter. During hack day, they began a