Browsing by Subject "Approximation theory"

Now showing items 41-60 of 80

    • Conference Object  

      Neural Networks in Comparing USN and Wageningen B-Series Marine Propellers 

      Neocleous, Costas K.; Schizas, Christos N. (2003)
      The USN-series of experimental data on marine propeller performance (Denny et al, 1989) were compared with fitted Wageningen B-Series data. A Kohonen network has been used to attempt finding non-obvious similarities between ...
    • Article  

      A nonoverlapping domain decomposition method for Legendre spectral collocation problems 

      Bialecki, B.; Karageorghis, Andreas (2007)
      We consider the Dirichlet boundary value problem for Poisson's equation in an L-shaped region or a rectangle with a cross-point. In both cases, we approximate the Dirichlet problem using Legendre spectral collocation, that ...
    • Article  

      A note on p/hp finite element methods for reaction-diffusion problems in polygonal domains 

      Xenophontos, Christos A. (2000)
      We present guidelines on how to choose the mesh and polynomial degree distribution for the approximation of reaction-diffusion problems in polygonal domains, in the context of the hp finite element method. These guidelines ...
    • Article  

      A note on the convergence rate of the finite element method for singularly perturbed problems using the Shishkin mesh 

      Xenophontos, Christos A. (2003)
      We consider the numerical approximation of singularly perturbed problems by the h version of the finite element method on a piecewise uniform, Shishkin mesh. It is well known that this method yields uniform approximations, ...
    • Conference Object  

      Note on the distribution of extreme wave crests 

      Baxevani, Anastassia; Hagberg, O.; Rychlik, I. (2005)
      The sea elevation at a fixed point is modelled by means of a second order model, which is a smooth algebraic function of a vector valued Gaussian process. Asymptotic methods, presented first in [1], are used to estimate ...
    • Conference Object  

      Nucleon electromagnetic and axial form factors with Nf=2 twisted mass fermions at the physical point 

      Alexandrou, Constantia; Constantinou, Martha; Hadjiyiannakou, Kyriakos; Kallidonis, Christos; Koutsou, Giannis; Jansen, K.; Ottnad, K.; Vaquero, A. (Proceedings of Science (PoS), 2016)
      We present results for the nucleon electromagnetic and axial form factors using an Nf=2 twisted mass fermion ensemble with pion mass of about 131 MeV. We use multiple sink-source separations to identify excited state ...
    • Conference Object  

      Nucleon generalized form factors with twisted mass fermions 

      Alexandrou, Constantia; Constantinou, Martha; Drach, V.; Jansen, K.; Kallidonis, Christos; Koutsou, Giannis (Proceedings of Science (PoS), 2013)
      We present results on the nucleon form factors, momentum fraction and helicity moment for Nf = 2 and Nf = 2+1+1 twisted mass fermions for a number of lattice volumes and lattice spacings. First results for a new Nf = 2 ...
    • Article  

      A numerical study on the finite element solution of singularly perturbed systems of reaction-diffusion problems 

      Xenophontos, Christos A.; Oberbroeckling, L. (2007)
      We consider the approximation of singularly perturbed systems of reaction-diffusion problems, with the finite element method. The solution to such problems contains boundary layers which overlap and interact, and the ...
    • Article  

      Observation of diffractive J/ψ production at the Fermilab Tevatron 

      Affolder, T.; Akimoto, H.; Akopian, A.; Albrow, M. G.; Amaral, P.; Amidei, D.; Anikeev, K.; Antos, J.; Apollinari, G.; Arisawa, T.; Artikov, A.; Asakawa, T.; Ashmanskas, W.; Azfar, F.; Azzi-Bacchetta, P.; Bacchetta, N.; Bachacou, H.; Bailey, S.; de Barbaro, P.; Barbaro-Galtieri, A.; Barnes, V. E.; Barnett, B. A.; Baroiant, S.; Barone, M.; Bauer, G.; Bedeschi, F.; Belforte, S.; Bell, W. H.; Bellettini, G.; Bellinger, J.; Benjamin, D.; Bensinger, J.; Beretvas, Andrew; Berge, J. P.; Berryhill, J.; Bhatti, A.; Binkley, M.; Bisello, D.; Bishai, M.; Blair, R. E.; Blocker, C.; Bloom, K.; Blumenfeld, B.; Blusk, S. R.; Bocci, A.; Bodek, A.; Bokhari, W.; Bolla, G.; Bonushkin, Yu Ye; Borras, K.; Bortoletto, D.; Boudreau, J.; Brandl, A.; van den Brink, S.; Bromberg, C.; Brozovic, M.; Brubaker, E.; Bruner, N.; Buckley-Geer, E.; Budagov, J.; Budd, H. S.; Burkett, K.; Busetto, G.; Byon-Wagner, A.; Byrum, K. L.; Cabrera, S.; Calafiura, P.; Campbell, M.; Carithers, W.; Carlson, J.; Carlsmith, D.; Caskey, W.; Castro, A.; Cauz, D.; Cerri, A.; Chan, A. W.; Chang, P. S.; Chang, P. T.; Chapman, J.; Chen, C.; Chen, Y. C.; Cheng, M. -T; Chertok, M.; Chiarelli, G.; Chirikov-Zorin, I.; Chlachidze, G.; Chlebana, F.; Christofek, L.; Chu, M. L.; Chung, Y. S.; Ciobanu, C. I.; Clark, A. G.; Connolly, A.; Convery, M. E.; Conway, J.; Cordelli, M.; Cranshaw, J.; Cropp, R.; Culbertson, R.; Dagenhart, D.; D'Auria, S.; DeJongh, F.; Dell'Agnello, Simone; Dell'Orso, M.; Demortier, L.; Deninno, M.; Derwent, P. F.; Devlin, T.; Dittmann, J. R.; Dominguez, A.; Donati, S.; Done, J.; D'Onofrio, M.; Dorigo, T.; Eddy, N.; Einsweiler, K.; Elias, John E.; Engels, Eugene; Erbacher, R.; Errede, D.; Errede, S.; Fan, Q.; Feild, R. G.; Fernandez, J. P.; Ferretti, C.; Field, R. D.; Fiori, I.; Flaugher, B.; Foster, G. W.; Franklin, M.; Freeman, J.; Friedman, J.; Fukui, Y.; Furic, I.; Galeotti, S.; Gallas, A.; Gallinaro, M.; Gao, T.; Garcia-Sciveres, M.; Garfinkel, A. F.; Gatti, P.; Gay, C.; Gerdes, D. W.; Giannetti, P.; Glagolev, V.; Glenzinski, D.; Gold, M.; Goldstein, J.; Gorelov, I.; Goshaw, A. T.; Gotra, Y.; Goulianos, Konstantin; Green, C.; Grim, G.; Gris, P.; Groer, L.; Grosso-Pilcher, C.; Guenther, M.; Guillian, G.; Guimaraes da Costa, J.; Haas, R. M.; Haber, C.; Hahn, S. R.; Hall, C.; Handa, T.; Handler, R.; Hao, W.; Happacher, F.; Hara, K.; Hardman, A. D.; Harris, R. M.; Hartmann, F.; Hatakeyama, K.; Hauser, J.; Heinrich, J.; Heiss, A.; Herndon, M.; Hill, C.; Hoffman, K. D.; Holck, C.; Hollebeek, R.; Holloway, L.; Hughes, R.; Huston, J.; Huth, J.; Ikeda, H.; Incandela, J.; Introzzi, G.; Iwai, J.; Iwata, Y.; James, E.; Jones, M.; Joshi, U.; Kambara, H.; Kamon, T.; Kaneko, T.; Karr, K.; Kasha, H.; Kato, Y.; Keaffaber, T. A.; Kelley, K.; Kelly, M.; Kennedy, R. D.; Kephart, R.; Khazins, D.; Kikuchi, T.; Kilminster, B.; Kim, B. J.; Kim, D. H.; Kim, H. S.; Kim, M. J.; Kim, S. B.; Kim, S. H.; Kim, Y. K.; Kirby, M.; Kirk, M.; Kirsch, L.; Klimenko, S.; Koehn, P.; Kondo, K.; Konigsberg, J.; Korn, A.; Korytov, A.; Kovács, Eve V.; Kroll, J.; Kruse, M.; Kuhlmann, S. E.; Kurino, K.; Kuwabara, T.; Laasanen, A. T.; Lai, N.; Lami, S.; Lammel, S.; Lancaster, J.; Lancaster, M.; Lander, R.; Lath, A.; Latino, G.; LeCompte, T.; Lee, A. M.; Lee, K.; Leone, S.; Lewis, J. D.; Lindgren, M.; Liss, T. M.; Liu, J. B.; Liu, Y. C.; Litvintsev, D. O.; Lobban, O.; Lockyer, N.; Loken, J.; Loreti, M.; Lucchesi, D.; Lukens, P.; Lusin, S.; Lyons, L.; Lys, J.; Madrak, R.; Maeshima, K.; Maksimovic, P.; Malferrari, L.; Mangano, M.; Mariotti, M.; Martignon, G.; Martin, A.; Matthews, J. A. J.; Mayer, J.; Mazzanti, P.; McFarland, K. S.; McIntyre, P.; McKigney, E.; Menguzzato, M.; Menzione, A.; Mesropian, C.; Meyer, A.; Miao, T.; Miller, R.; Miller, J. S.; Minato, H.; Miscetti, S.; Mishina, M.; Mitselmakher, G.; Moggi, N.; Moore, E.; Moore, R.; Morita, Y.; Moulik, T.; Mulhearn, M.; Mukherjee, A.; Muller, T.; Munar, A.; Murat, P.; Murgia, S.; Nachtman, J.; Nagaslaev, V.; Nahn, S.; Nakada, H.; Nakano, I.; Nelson, C.; Nelson, T.; Neu, C.; Neuberger, D.; Newman-Holmes, C.; Ngan, C. -Y P.; Niu, H.; Nodulman, L.; Nomerotski, A.; Oh, S. H.; Oh, Y. D.; Ohmoto, T.; Ohsugi, T.; Oishi, R.; Okusawa, T.; Olsen, J.; Orejudos, W.; Pagliarone, C.; Palmonari, F.; Paoletti, R.; Papadimitriou, Vaia; Partos, D.; Patrick, J.; Pauletta, G.; Paulini, M.; Paus, C.; Pellett, D.; Pescara, L.; Phillips, T. J.; Piacentino, G.; Pitts, K. T.; Pompos, A.; Pondrom, L.; Pope, G.; Popovic, M.; Prokoshin, F.; Proudfoot, J.; Ptohos, Fotios; Pukhov, O.; Punzi, G.; Rakitine, A.; Ratnikov, F.; Reher, D.; Reichold, A.; Ribon, A.; Riegler, W.; Rimondi, F.; Ristori, L.; Riveline, M.; Robertson, W. J.; Robinson, A.; Rodrigo, T.; Rolli, S.; Rosenson, L.; Roser, R.; Rossin, R.; Roy, A.; Ruiz, A.; Safonov, A.; Denis, R. S.; Sakumoto, W. K.; Saltzberg, D.; Sanchez, C.; Sansoni, A.; Santi, L.; Sato, H.; Savard, P.; Schlabach, P.; Schmidt, E. E.; Schmidt, M. P.; Schmitt, M.; Scodellaro, L.; Scott, A.; Scribano, A.; Segler, S.; Seidel, S.; Seiya, Y.; Semenov, A.; Semeria, F.; Shah, T.; Shapiro, M. D.; Shepard, P. F.; Shibayama, T.; Shimojima, M.; Shochet, M.; Sidoti, A.; Siegrist, J.; Sill, A.; Sinervo, P.; Singh, P.; Slaughter, A. J.; Sliwa, K.; Smith, C.; Snider, F. D.; Solodsky, A.; Spalding, J.; Speer, T.; Sphicas, Paris A.; Spinella, F.; Spiropulu, Maria; Spiegel, L.; Steele, J.; Stefanini, A.; Strologas, John; Strumia, F.; Stuart, D.; Sumorok, K.; Suzuki, T.; Takano, T.; Takashima, R.; Takikawa, K.; Tamburello, P.; Tanaka, M.; Tannenbaum, B.; Tecchio, M.; Tesarek, R.; Teng, P. K.; Terashi, K.; Tether, S.; Thompson, A. S.; Thurman-Keup, R.; Tipton, P.; Tkaczyk, S.; Toback, D.; Tollefson, K.; Tollestrup, A.; Tonelli, D.; Toyoda, H.; Trischuk, W.; de Trocóniz, J. F.; Tseng, J.; Turini, N.; Ukegawa, F.; Vaiciulis, T.; Valls, J.; Vejcik, S.; Velev, G.; Veramendi, G.; Vidal, R.; Vila, I.; Vilar, R.; Volobouev, I.; von der Mey, M.; Vucinic, D.; Wagner, R. G.; Wagner, R. L.; Wallace, N. B.; Wan, Z.; Wang, C.; Wang, M. J.; Ward, B.; Waschke, S.; Watanabe, T.; Waters, D.; Watts, T.; Webb, R.; Wenzel, H.; Wester, W. C.; Wicklund, A. B.; Wicklund, E.; Wilkes, T.; Williams, H. H.; Wilson, P.; Winer, B. L.; Winn, D.; Wolbers, S.; Wolinski, D.; Wolinski, J.; Wolinski, S.; Worm, S.; Wu, X.; Wyss, J.; Yao, W.; Yeh, G. P.; Yeh, P.; Yoh, J.; Yosef, C.; Yoshida, T.; Yu, I.; Yu, S.; Yu, Z.; Zanetti, A.; Zetti, F.; Zucchelli, S. (2001)
      The first observation of diffractive J/ψ(→μ+μ-) production in p̄p collisions at s√=1.8 TeV was presented. Events were selected with a pair of muon candidates using a three-level dimuon trigger system. The dimuon mass ...
    • Article  

      On efficient AR spectral estimation for long-range predictions 

      Karagrigoriou, Alex; Vonta, Filia (2005)
      This article discusses the concept of asymptotic efficiency from the frequency domain point of view making use of the direct method for multiple prediction. In particular, it is shown that with the use of a new autoregressive ...
    • Article  

      On the effects of using curved elements in the approximation of the Reissner-Mindlin plate by the p version of the finite element method 

      Kurtz, J.; Xenophontos, Christos A. (2003)
      We consider the approximation of the Reissner-Mindlin plate model by the standard Galerkin p version finite element method. Under the assumption of sufficient smoothness on the solution, we illustrate that the method is ...
    • Article  

      Optical and electrical properties of selectively delta-doped strained InxGa1-xAs/GaAs quantum wells 

      Ke, M. L.; Chen, X.; Zervos, Matthew; Nawaz, R.; Elliott, M.; Westwood, D. I.; Blood, P.; Godfrey, M. J.; Williams, R. H. (1996)
      We report here an investigation of selectively delta-doped strained InGaAs/GaAs quantum wells. Electronic structures of the systems were calculated by self-consistently solving the Schrödinger and Poisson equations and the ...
    • Article  

      Optimal mesh design for the finite element approximation of reaction-diffusion problems 

      Xenophontos, Christos A. (2002)
      We consider the numerical approximation of singularly perturbed problems, and in particular reactiondiffusion problems, by the h version of the finite element method. We present guidelines on how to design non-uniform ...
    • Article  

      A p-version MITC finite element method for Reissner-Mindlin plates with curved boundaries 

      Xenophontos, Christos A.; Kurtz, J.; Fulton, S. (2006)
      We consider the approximation of Reissner-Mindlin plates with curved boundaries, using a p-version MITC finite element method. We describe in detail the formulation and implementation of the method, and emphasize the need ...
    • Article  

      Piecewise analytic approximation for Bose-Einstein condensates in isotropic harmonic traps 

      Theodorakis, Stavros (2004)
      Analytic simulacra of the wave functions in the regions around the origin and far from the origin were constructed to emulate the ground state and the single-vortex state of a Bose-Einstein condensate in an isotropic ...
    • Article  

      Piecewise linear emulation of propagating fronts as a method for determining their speeds 

      Theodorakis, Stavros; Svoukis, E. (2003)
      The selected speed of pushed fronts was found through analytic calculations. The resulting analytic solution constitutes an excellent approximation to the exact propagating front, yielding also the correct value for the ...
    • Article  

      Piecewise linear emulator of the nonlinear Schrödinger equation and the resulting analytic solutions for Bose-Einstein condensates 

      Theodorakis, Stavros (2003)
      A most general method for finding very good analytic approximate solutions to the cubic nonlinear Schrodinger equation is presented. This method applies whenever the nonlinearity in that equation is a purely cubic one. It ...
    • Article  

      Poisson approximation for a sum of dependent indicators: An alternative approach 

      Papadatos, Nickos; Papathanasiou, Vassilis (2002)
      The random variables X1, X2,...,Xn are said to be totally negatively dependent (TND) if and only if the random variables Xi and Σj≠i Xj are negatively quadrant dependent for all i. Our main result provides, for TND 0-1 ...
    • Article  

      The production and decay kinetics of CIOO in water and freon-11: A time-resolved resonance Raman study 

      Hayes, Sophia C.; Thomsen, C. L.; Reid, P. J. (2001)
      The production and decay kinetics of ClOO in water and freon-11 were studied using time-resolved resonance Raman (TRRR) spectroscopy. The formation of ClOO following OClO photoexcitation at 390 nm was investigated using ...
    • Article  

      Rate of convergence for vanishing viscosity approximations to hyperbolic balance laws 

      Christoforou, Cleopatra; Trivisa, K. (2011)
      The rate of convergence for vanishing viscosity approximations to hyperbolic balance laws is established. The result applies to systems that are strictly hyperbolic and genuinely nonlinear with a source term satisfying a ...