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2. Non-Asymptotic Performance Analysis of Size-Based Routing Policies

Author

Bachmat, E. and Doncel, J.

Subjects
Computer Science - Performance, Mathematics - Optimization and Control, Mathematics - Probability
Abstract

We investigate the performance of two size-based routing policies: the Size Interval Task Assignment (SITA) and Task Assignment based on Guessing Size (TAGS). We consider a system with two servers and Bounded Pareto distributed job sizes with tail parameter 1 where the difference between the size of the largest and the smallest job is finite. We show that the ratio between the mean waiting time of TAGS over the mean waiting time of SITA is unbounded when the largest job size is large and the arrival rate times the largest job size is less than one. We provide numerical experiments that show that our theoretical findings extend to Bounded Pareto distributed job sizes with tail parameter different to 1.

Published
2020

4. Certified Genetic Algorithms: Crossover Operators for Permutations

Author

Aguado, F., Doncel, J. L., Molinelli, J. M., Pérez, G., Vidal, C., Vieites, A., Hutchison, David, editor, Kanade, Takeo, editor, Kittler, Josef, editor, Kleinberg, Jon M., editor, Mattern, Friedemann, editor, Mitchell, John C., editor, Naor, Moni, editor, Nierstrasz, Oscar, editor, Pandu Rangan, C., editor, Steffen, Bernhard, editor, Sudan, Madhu, editor, Terzopoulos, Demetri, editor, Tygar, Doug, editor, Vardi, Moshe Y., editor, Weikum, Gerhard, editor, Moreno Díaz, Roberto, editor, Pichler, Franz, editor, and Quesada Arencibia, Alexis, editor

Published
2007
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10. Neutral beam injection optimization at TJ-II

Author

Fuentes, C., Liniers, M., Wolfers, G., Alonso, J., Marcon, G., Carrasco, R., Guasp, J., Acedo, M., Sánchez, E., Medrano, M., García, A., Doncel, J., Alejaldre, C., Tsai, C.C., Barber, G., and Sparks, D.

Published
2005
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14. Overview of TJ-II flexible heliac results

Author

Ascası́bar, E, Alejaldre, C, Alonso, J, Almoguera, L, Baciero, A, Balbı́n, R, Blaumoser, M, Botija, J, Brañas, B, de la Cal, E, Cappa, A, Castellano, J, Carrasco, R, Castejón, F, Cepero, J.R, Cremy, C, Doncel, J, Eguilior, S, Estrada, T, Fernández, A, Fuentes, C, Garcı́a, A, Garcı́a-Cortés, I, Guasp, J, Herranz, J, Hidalgo, C, Jiménez, J.A, Kirpitchev, I, Krivenski, V, Labrador, I, Lapayese, F, Likin, K, Liniers, M, López-Fraguas, A, López-Sánchez, A, de la Luna, E, Martı́n, R, Martı́nez-Laso, L, Medrano, M, Méndez, P, McCarthy, K.J, Medina, F, van Milligen, B, Ochando, M, Pacios, L, Pastor, I, Pedrosa, M.A, de la Peña, A, Portas, A, Qin, J, Rodrı́guez-Rodrigo, L, Romero, J, Salas, A, Sánchez, E, Sánchez, J, Tabarés, F, Tafalla, D, Tribaldos, V, Vega, J, and Zurro, B

Published
2001
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17. The ecolocgy of 'dehesa' grasslands of Badajoz province. A preleiminary report on vegetation analysis by a multivariate method (analyse des correspondences de Benzecri)

Author

Marañón, Teodoro, Figueroa, Manuel E., Cota, H., Doncel, J. L., García Novo, F., and Universidad de Sevilla. Departamento de Biología Vegetal y Ecología

Abstract

9 páginas, 1 figura, 3 tablas, 8 referencias., [EN]: 42 grasslands of Badajoz and Huelva provinces (Western Spain) were studied recording plant species frequencies with 10 quadrats (20 X 20 cm.) randomly distributed over 2 X 2 m. plots taken under the crown on Quercus rotundifolia trees. Soil samples collected on every plot were analysed for pH, orgainic matter, P, Ca, K and Na. Frequency matrix (80 plant species X 42 plots) was analysed by the method know as "Analyse des Correspondences" (BENZECRI, 1973). The two main components (accounting for about 20% of the overall variation) separate plots into six recognizable groups (grassland types). A preliminary attempt to interpret those groups is made in terms of biotope (soil and substrate) differencies. The two main directions of variation found correspond to an eutrophization gradient (poor acidic versus rich basic soils) and to an erosion gradient (soil erosion versus pedogenesis). Secondary causes of variation are interpreted as due to lithology, climate and management. Further analysis of present data is currently under way., [ES]: Se han realizado inventarios de frecuencia de herbáceas (diez cuadros de 20 X 20 cm. en inventario) en 42 pastizales de dehesa de Badajoz y norte de Huelva, correspondientes a los principales tipos litológicos. La vegetación se estudió con el análisis de correspondencias. Se detectan seis tipos principales de pastizal que se han interpretado parcialmente con los datos de suelo y sustrato ahora disponibles. En comunicaciones posteriores se completará el análisis con ayuda de otras medidas ahora en realización.

Published
2011

19. Perturbative transport experiments on TJ-II Flexible Heliac

Author

Castejón, F., Ascasíbar, E., Alejaldre, C., Alonso, J., Almoguera, L., Baciero, A., Balbín, R., Blanco, E., Blaumoser, M., Botija, J., Brañas, B., Cappa, A., Carrasco, R., Cepero, J.R., Chmyga, A.A., Doncel, J., Dreval, N.B., Eguilior, S., Eliseev, L., Estrada, T., Fedyanin, O., Fernández, A., Fontdecaba, J.M., Fuentes, C., García, A., García-Cortés, I., Gonçalves, B., Guasp, J., Herranz, J., Hidalgo, A., Hidalgo, C., Jiménez, J.A., Kirpitchev, I., Khrebtov, S.M., Komarov, A.D., Kozachok, A.S., Krupnik, L., Lapayese, F., Likin, K., Liniers, M., López-Bruna, D., López-Fraguas, A., López-Rázola, J., López-Sánchez, A., de la Luna, E., Malaquias, A., Martín, R., Medrano, M., Melnikov, A.V., Méndez, P., McCarthy, K.J., Medina, F., van Milligen, B., Nedzelskiy, I.S., Ochando, M., Pacios, L., Pastor, I., Pavlov, S.S., Pedrosa, M.A., de la Peña, A., Petrov, A., Petrov, S., Portas, A., Romero, J., Rodríguez-Rodrigo, L., Salas, A., Sánchez, E., Sánchez, J., Sarksian, K., Schchepetov, S., Skvortsova, N., Tabarés, F., Tafalla, D., Tribaldos, V., Varandas, C.F.A., Vega, J., and Zurro, B.

Subjects
Magnetic confinement
Abstract

Transport properties of TJ-II are explored performing perturbative experiments and taking advantage of TJ-II flexibility. Rotational transform can be varied in a wide range, which allows one to introduce low order rationals and to study their effect on transport. On the other hand, confinement properties can be studied at very different rotational transform values and for different values of magnetic shear: Experiments on influence of the magnetic shear on confinement are reported. In these cases a Ohmic current has been induced in TJ-II plasma to modify magnetic shear and to evaluate itsd effect on confinement, showing that negative shear improves the confinement. Heat transport is also reduced by locating a low order rational near the power deposition profile. Plasma potential profiles have been recently measured in some configurations up to the plasma core with the Heavy Ion Beam Probe (HIBP) diagnostic and the electric field values measured in low-density plasmas are consistent with neoclassical calculations near the plasma core. Plasma edge turbulent transport has been studied in configurations that are marginally stable due to decreased magnetic well. Results show a dynamical coupling between gradients and turbulent transport. Finally, cold pulse propagation has been studied showing ballistic non diffusive propagation.

Published
2002

20. Optimal congestion control of TCP flows for internet routers

Author

Avrachenkov, K., Ayesta, U., Doncel, J., Jacko, P., Avrachenkov, K., Ayesta, U., Doncel, J., and Jacko, P.

Abstract

In this work we address the problem of fast and fair transmission of ows in a router, which is a fundamental issue in networks like the Internet. We model the interaction between a TCP source and a bottleneck queue with the objective of designing optimal packet admission controls in the bottleneck queue. We focus on the relaxed version of the problem obtained by relaxing the fixed buffer capacity constraint that must be satisfied at all time epoch. The relaxation allows us to reduce the multi-ow problem into a family of single-ow problems, for which we can analyze both theoretically and numerically the existence of optimal control policies of special structure. In particular, we show that for a variety of parameters, TCP ows can be optimally controlled in routers by so-called index policies. We have implemented index policies in Network Simulator-3 (NS-3) and compared its performance with DropTail and RED buffers. The simulation results show that the index policy has several desirable properties with respect to fairness and efficiency.

Published
2012

21. Latest physics results of TJ-II flexible heliac

Author

Castejón, F., Alejaldre, C., Alonso, J., Almoguera, L., Ascasíbar, E., Baciero, A., Balbín, R., Blaumoser, M., Botija, J., Brañas, B., de la Cal, E., Cappa, A., Carrasco, R., Cepero, J.R., Cremy, C., Doncel, J., Eguilior, S., Estrada, T., Fernández, A., Fuentes, C., García, A., García-Cortés, I., Guasp, J., Herranz, J., Hidalgo, C., Jiménez, J.A., Kirpitchev, I., Krivenski, V., Labrador, I., Lapayese, F., Likin, K., Liniers, M., López-Fraguas, A., López-Sánchez, A., de la Luna, E., Martín, R., Martínez-Laso, L., Medrano, M., Méndez, P., McCarthy, K.J., Medina, F., van Milligen, B., Ochando, M., Pacios, L., Pastor, I., Pedrosa, M.A., de la Peña, A., Portas, A., Qin, J., Rodríguez-Rodrigo, L., Salas, A., Sánchez, E., Sánchez, J., Tabarés, F., Tafalla, D., Tribaldos, V., Vega, J., and Zurro, B.

Subjects
Magnetic confinement
Abstract

This paper is devoted to the presentation of the most relevant recent Physics results obtained in the TJ-II flexible heliac. Firstly ECRH modulation and plasma breakdown studies are summarised; then the particle control techniques used to obtain reproducible discharges with density under control are presented. Transport studies show internal heat transport barriers that reduce heat conductivity to neoclassical values, and ELM-like transport events, similar to those observed in tokamaks and in other stellarators before and during H mode transition. Evidence of ExB sheared has been observed both in the proximity of rational surfaces. Finally, a high resolution Thomsom Scattering system has shown Te and ne profile structures.

Published
2000

22. Estudio ecológico de los pastizales de dehesa en la provincia de Badajoz. Tipificación preliminar de la vegetación empleando el análisis de correspondencias

Author

Marañón, T., Figueroa, E., Cota, H., Doncel, J. L., García Novo, F., Marañón, T., Figueroa, E., Cota, H., Doncel, J. L., and García Novo, F.

Abstract

Se han realizado inventarios de frecuencia de herbáceas {diez cuadros de 20 X 20 cm. en inventario) en 42 pastizales de dehesa de Badajoz y norte de Huelva, correspondientes a los principales tipos litológicos. La vegetación se estudió con el análisis de correspondencias. Se detectan seis tipos principales de pastizal que se han interpretado parcialmente con los datos de suelo y sustrato ahora disponibles. En comunicaciones posteriores se completará el análisis con ayuda de otras medidas ahora en realización.

Published
2011

28. Thermographic calorimetry of the neutral beam injectors heating beams at TJ-II

Author

Fuentes, C., primary, Liniers, M., additional, Guasp, J., additional, Doncel, J., additional, Botija, J., additional, Wolfers, G., additional, Alonso, J., additional, Acedo, M., additional, Sánchez, E., additional, Marcon, G., additional, Weber, M., additional, Carrasco, R., additional, Sarasola, X., additional, Zurro, B., additional, and Tera, J., additional

Published
2006
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29. Overview of TJ-II experiments

Author

Hidalgo, C, primary, Alejaldre, C, additional, Alonso, A, additional, Alonso, J, additional, Almoguera, L, additional, Aragón, F. de, additional, Ascasíbar, E, additional, Baciero, A, additional, Balbín, R, additional, Blanco, E, additional, Botija, J, additional, Brañas, B, additional, Calderón, E, additional, Cappa, A, additional, Carmona, J.A, additional, Carrasco, R, additional, Castejón, F, additional, Cepero, J.R, additional, Chmyga, A.A, additional, Doncel, J, additional, Dreval, N.B, additional, Eguilior, S, additional, Eliseev, L, additional, Estrada, T, additional, Ferreira, J.A, additional, Fernández, A, additional, Fontdecaba, J.M, additional, Fuentes, C, additional, García, A, additional, García-Cortés, I, additional, Gonçalves, B, additional, Guasp, J, additional, Herranz, J, additional, Hidalgo, A, additional, Jiménez, R, additional, Jiménez, J.A, additional, Jiménez-Rey, D, additional, Kirpitchev, I, additional, Khrebtov, S.M, additional, Komarov, A.D, additional, Kozachok, A.S, additional, Krupnik, L, additional, Lapayese, F, additional, Liniers, M, additional, López-Bruna, D, additional, López-Fraguas, A, additional, López-Rázola, J, additional, López-Sánchez, A, additional, Luna, E. de la, additional, Marcon, G, additional, Martín, R, additional, McCarthy, K.J, additional, Medina, F, additional, Medrano, M, additional, Melnikov, A.V, additional, Méndez, P, additional, Milligen, B. van, additional, Nedzelskiy, I.S, additional, Ochando, M, additional, Orozco, O, additional, Pablos, J.L. de, additional, Pacios, L, additional, Pastor, I, additional, Pedrosa, M.A, additional, Peña, A. de la, additional, Pereira, A, additional, Petrov, A, additional, Petrov, S, additional, Portas, A, additional, Rapisarda, D, additional, Rodríguez-Rodrigo, L, additional, Rodríguez-Solano, E, additional, Romero, J, additional, Salas, A, additional, Sánchez, E, additional, Sánchez, J, additional, Sánchez, M, additional, Sarksian, K, additional, Silva, C, additional, Schchepetov, S, additional, Skvortsova, N, additional, Tabarés, F, additional, Tafalla, D, additional, Tolkachev, A, additional, Tribaldos, V, additional, Vargas, I, additional, Vega, J, additional, Wolfers, G, additional, and Zurro, B, additional

Published
2005
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31. Certified Genetic Algorithms: Crossover Operators for Permutations.

Author

Hutchison, David, Kanade, Takeo, Kittler, Josef, Kleinberg, Jon M., Mattern, Friedemann, Mitchell, John C., Naor, Moni, Nierstrasz, Oscar, Pandu Rangan, C., Steffen, Bernhard, Sudan, Madhu, Terzopoulos, Demetri, Tygar, Doug, Vardi, Moshe Y., Weikum, Gerhard, Moreno Díaz, Roberto, Pichler, Franz, Quesada Arencibia, Alexis, Aguado, F., and Doncel, J. L.

Abstract

In the context of Genetic Algorithms, the use of permutations for representing the chromosomes, instead of the most common binary encoding, has turned out to be more natural and convenient in order to resolve some optimization problems. With the purpose of adapting the classical crossover to this special representation, several proposals can be found in the literature [2,3,8]. In this paper we use Coq to formally implement some of these crossover operators and also to verify that they satisfy the required specifications. As we have considered permutations of (possibly) repeated elements, we can cover a wider collection of applications. [ABSTRACT FROM AUTHOR]

Published
2007
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32. Confinement and stability on the TJ-II stellarator

Author

Ascas bar, E, primary, Alejaldre, C, additional, Alonso, J, additional, Almoguera, L, additional, Baciero, A, additional, Balb n, R, additional, Blanco, E, additional, Blaumoser, M, additional, Botija, J, additional, Bra as, B, additional, Cappa, A, additional, Carrasco, R, additional, Castej n, F, additional, Cepero, J R, additional, Chmyga, A A, additional, Doncel, J, additional, Dreval, N B, additional, Eguilior, S, additional, Eliseev, L, additional, Estrada, T, additional, Fedyanin, O, additional, Fern ndez, A, additional, Fontdecaba, J M, additional, Fuentes, C, additional, Garc a, A, additional, Garc a-Cort s, I, additional, Gon alves, B, additional, Guasp, J, additional, Herranz, J, additional, Hidalgo, A, additional, Hidalgo, C, additional, Jim nez, J A, additional, Kirpitchev, I, additional, Khrebtov, S M, additional, Komarov, A D, additional, Kozachok, A S, additional, Krupnik, L, additional, Lapayese, F, additional, Likin, K, additional, Liniers, M, additional, L pez-Bruna, D, additional, L pez-Fraguas, A, additional, L pez-R zola, J, additional, L pez-S nchez, A, additional, Luna, E de la, additional, Malaquias, A, additional, Mart n, R, additional, Medrano, M, additional, Melnikov, A V, additional, M ndez, P, additional, McCarthy, K J, additional, Medina, F, additional, Milligen, B van, additional, Nedzelskiy, I S, additional, Ochando, M, additional, Pacios, L, additional, Pastor, I, additional, Pedrosa, M A, additional, Pe a, A de la, additional, Petrov, A, additional, Petrov, S, additional, Portas, A, additional, Romero, J, additional, Rodr guez-Rodrigo, L, additional, Salas, A, additional, S nchez, E, additional, S nchez, J, additional, Sarksian, K, additional, Schchepetov, S, additional, Skvortsova, N, additional, Tabar s, F, additional, Tafalla, D, additional, Tribaldos, V, additional, Varandas, C F A, additional, Vega, J, additional, and Zurro, B, additional

Published
2002
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34. Transport Properties in the TJ-II Flexible Heliac.

Author

Castejón, F., Ascasíbar, E., Alejaldre, C., Alonso, J., Almoguera, L., Baciero, A., Balbín, R., Blanco, E., Blaumoser, M., Botija, J., Brañas, B., Cappa, A., Carrasco, R., Cepero, J. R., Chmyga, A. A., Doncel, J., Dreval, N. B., Eguilior, S., and Eliseev, L.

Subjects
PLASMA density, PLASMA gases, HEAVY ions, PLASMA turbulence, SHEAR flow
Abstract

TJ-II flexibility is exploited to perform an investigation on the transport properties of this device. Rotational transform can be varied in a wide range, which allows one to introduce low order rationals and to study their effect on transport. On the other hand, confinement properties can be studied at very different rotational transform values and for different values of magnetic shear: Experiments on influence of the magnetic shear on confinement are reported. Plasma potential profiles have been recently measured in some configurations up to the plasma core with the Heavy Ion Beam Probe (HIBP) diagnostic and the electric field values measured in low-density plasmas are consistent with neoclassical calculations near the plasma core. Plasma edge turbulent transport has been studied in configurations that are marginally stable due to decreased magnetic well. Results show a dynamical coupling between gradients and turbulent transport. [ABSTRACT FROM AUTHOR]

Published
2003

35. Vandellos: A European site for ITER.

Author

Alejaldre, C., Doncel, J., Ibarra, A., Medrano, M., Branas, B., Garcia, A., Rodriguez-Rodrigo, L., Jimenez, J.A., Balbin, R., Sanchez de Mora, M.A., Alcala, F., Diez, J.E., Prades, A., Sola, R., Sedano, L., Robles, B., Suanez, A., Saez, R., Varela, M., and Sancho, C.

Published
2003
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36. Review of confinement and transport studies in the TJ-II flexible heliac

Author

Alejaldre, C., primary, Almoguera, L., additional, Alonso, J., additional, Ascasíbar, E., additional, Baciero, A., additional, Balbín, R., additional, Blaumoser, M., additional, Botija, J., additional, Brañas, B., additional, Cal, E. de la, additional, Cappa, A., additional, Carrasco, R., additional, Castejón, F., additional, Castellano, J., additional, Cepero, J.R., additional, Cremy, C., additional, Doncel, J., additional, Eguilior, S., additional, Estrada, T., additional, Fernández, A., additional, Fuentes, C., additional, García, A., additional, García-Cortés, I., additional, Guasp, J., additional, Herranz, J., additional, Hidalgo, C., additional, Jiménez, J.A., additional, Kirpitchev, I., additional, Krivenski, V., additional, Labrador, I., additional, Lapayese, F., additional, Likin, K., additional, Liniers, M., additional, López-Fraguas, A., additional, López-Sánchez, A., additional, Luna, E. de la, additional, Martín, R., additional, Martínez-Laso, L., additional, McCarthy, K.J., additional, Medina, F., additional, Medrano, M., additional, Méndez, P., additional, Milligen, B. van, additional, Ochando, M., additional, Pacios, L., additional, Pastor, I., additional, Pedrosa, M.A., additional, Peña, A. de la, additional, Portas, A., additional, Qin, J., additional, Rodríguez-Rodrigo, L., additional, Romero, J., additional, Salas, A., additional, Sánchez, E., additional, Sánchez, J., additional, Tabarés, F., additional, Tafalla, D., additional, Tribaldos, V., additional, Vega, J., additional, and Zurro, B., additional

Published
2001
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37. Upgrade of the JET neutral beam heating system.

Author

Ciric, D., Jones, T.T.C., Edwards, D.C., Martin, D., Bickley, A.J., Brown, D.P.D., Cox, S.J., Dines, A.J., Dobbing, J.A., Milnes, J.J., Shaw, S.R., Stork, D., Surrey, E., Watson, M.J., Young, D., Young, I.D., Bayetti, P., and Doncel, J.

Published
2002
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38. Confinement studies in the TJ-II stellarator

Author

Alejaldre, C, primary, Alonso, J, additional, Almoguera, L, additional, bar, E Ascasí, additional, Baciero, A, additional, Balbín, R, additional, Blaumoser, M, additional, Botija, J, additional, Brañas, B, additional, Cal, E de la, additional, Cappa, A, additional, Carrasco, R, additional, Castejón, F, additional, Cepero, J R, additional, Cremy, C, additional, Delgado, J M, additional, Doncel, J, additional, Dulya, C, additional, Estrada, T, additional, Fernández, A, additional, Fuentes, C, additional, García, A, additional, a-Cortés, I Garcí, additional, Guasp, J, additional, Herranz, J, additional, Hidalgo, C, additional, Jiménez, J A, additional, Kirpitchev, I, additional, Krivenski, V, additional, Labrador, I, additional, Lapayese, F, additional, Likin, K, additional, Linier, M, additional, López-Fraguas, A, additional, López-Sánchez, A, additional, Luna, E de la, additional, Martín, R, additional, Martinez, A, additional, Martínez-Laso, L, additional, Medrano, M, additional, Méndez, P, additional, McCarthy, K J, additional, Medina, F, additional, Milligen, B van, additional, Ochando, M, additional, Pacios, L, additional, Pastor, I, additional, Pedrosa, M A, additional, Peña, A de la, additional, Portas, A, additional, Qin, J, additional, Rodríguez-Rodrigo, L, additional, Salas, A, additional, Sánchez, E, additional, Sánchez, J, additional, Tabarés, F, additional, Tafalla, D, additional, Tribaldos, V, additional, Vega, J, additional, Zurro, B, additional, Akulina, D, additional, Fedyanin, O I, additional, Grebenshchikov, S, additional, Kharchev, N, additional, Meshcheryakov, A, additional, Sarksian, K A, additional, Barth, R, additional, Dijk, G van, additional, and Meiden, H van der, additional

Published
1999
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39. First plasmas in the TJ-II flexible Heliac

Author

Alejaldre, C, primary, Alonso, J, additional, Almoguera, L, additional, Ascasíbar, E, additional, Baciero, A, additional, Balbín, R, additional, Blaumoser, M, additional, Botija, J, additional, Brañas, B, additional, Cal, E de la, additional, Cappa, A, additional, Carrasco, R, additional, Castejón, F, additional, Cepero, J R, additional, Cremy, C, additional, Doncel, J, additional, Dulya, C, additional, Estrada, T, additional, Fernández, A, additional, Francés, M, additional, Fuentes, C, additional, García, A, additional, García-Cortés, I, additional, Guasp, J, additional, Herranz, J, additional, Hidalgo, C, additional, Jiménez, J A, additional, Kirpitchev, I, additional, Krivenski, V, additional, Labrador, I, additional, Lapayese, F, additional, Likin, K, additional, Liniers, M, additional, López-Fraguas, A, additional, López-Sánchez, A, additional, Luna, E de la, additional, Martín, R, additional, Martínez, A, additional, Medrano, M, additional, Méndez, P, additional, McCarthy, K, additional, Medina, F, additional, Milligen, B van, additional, Ochando, M, additional, Pacios, L, additional, Pastor, I, additional, Pedrosa, M.A, additional, Peña, A de la, additional, Portas, A, additional, Qin, J, additional, Rodríguez-Rodrigo, L, additional, Salas, A, additional, Sánchez, E, additional, Sánchez, J, additional, Tabarés, F, additional, Tafalla, D, additional, Tribaldos, V, additional, Vega, J, additional, Zurro, B, additional, Akulina, D, additional, Fedyanin, O I, additional, Grebenshchicov, S, additional, Kharchev, N, additional, Meshcheryakov, A, additional, Barth, R, additional, Dijk, G van, additional, Meiden, H van der, additional, and Petrov, S, additional

Published
1999
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40. From Wiener Index to Molecules

Author

Garcia, G. Cerruela, Ruiz, I. Luque, Gomez-Nieto, M. A., Doncel, J. A. Cabrero, and Plaza, A. Guevara

Abstract

In this paper we present an algorithm for the generation of molecular graphs with a given value of the Wiener index. The high number of graphs for a given value of the Wiener index is reduced thanks to the application of a set of heuristics taking into account the structural characteristics of the molecules. The selection of parameters as the interval of values for the Wiener index, the diversity and occurrence of atoms and bonds, the size and number of cycles, and the presence of structural patterns guide the processing of the heuristics generating molecular graphs with a considerable saving in computational cost. The modularity in the design of the algorithm allows it to be used as a pattern for the development of other algorithms based on different topological invariants, which allow for its use in areas of interest, say as involving combinatorial databases and screening in chemical databases.

Published
2005

41. Confinement and stability on the TJ-II stellarator

Author

Ascasíbar, E, Alejaldre, C, Alonso, J, Almoguera, L, Baciero, A, Balbín, R, Blanco, E, Blaumoser, M, Botija, J, Brañas, B, Cappa, A, Carrasco, R, Castejón, F, Cepero, J R, Chmyga, A A, Doncel, J, Dreval, N B, Eguilior, S, Eliseev, L, Estrada, T, Fedyanin, O, Fernández, A, Fontdecaba, J M, Fuentes, C, García, A, García-Cortés, I, Gonçalves, B, Guasp, J, Herranz, J, Hidalgo, A, Hidalgo, C, Jiménez, J A, Kirpitchev, I, Khrebtov, S M, Komarov, A D, Kozachok, A S, and L

Abstract

This paper describes a series of experiments performed in TJ-II stellarator with the aim of studying the influence of magnetic configuration on stability and transport properties of TJ-II plasmas. Plasma potential profiles have been measured in several configurations up to the plasma core with the heavy ion beam probe diagnostic. Low-order rational surfaces have been positioned at different plasma radii observing the effect on transport features. Plasma edge turbulent transport has been studied in configurations that are marginally stable due to decreased magnetic well. Results show a dynamical coupling between gradients and turbulent transport. Experiments on the influence of magnetic shear on confinement are reported. Global confinement issues as well as enhanced confinement regimes found in TJ-II are discussed as well.

Published
2002

43. Block sampling: a new method for the study of grasslands

Author

Doncel, J. L., Marañón, Teodoro, and García Novo, F.

Abstract

10 páginas, 1 tabla, 6 referencias.-- Ponencia presentada la mencionada Reunión científica celebrada del 2-5 de mayo 1977 en Córdoba, España., [EN]: Block sampling, a new method for grassland studies of vegetation is described and evaluated. The method cons ists of collecting undisturbed soil samples 25x25x15 cm. Growing them in greenhouses it is possible a detailed study of vegetation. Comparing the method with standard procedures (quadrat sampling for frequency assesment of abundance) it is shown that block sampling provides better information for unit area. Also it gives useful data for vegetation studies. Whenever unfavourable conditions of vegetation (i.e. ressistence forms during cold or dry seasons) hamper its study, block sampling may be useful. In those areas with prevailing arid climate the method will probe extremely interesting., [ES]: Se describe un nuevo método para el muestreo de la vegetación herbacea; el método consiste en la recolección de bloques de suelo inalterado, de 25x 25x15 cm que se mantienen en camaras de cultivo en condiciones favorables para el desarrollo de la vegetación. Los resultados del método se comparan con los obtenidos por el muestreo clásico (frecuencias). Se discute su aplicación en el estudio de pastizales, así como sus posi bilidades para estudiar vegetación en ondiciones desfavorables o de resistencia.

Published
1977

44. Estudio ecológico de los pastizales de dehesa en la provincia de Badajoz. Tipificación preliminar de la vegetación empleando el análisis de correspondencias

Author

Universidad de Sevilla. Departamento de Biología Vegetal y Ecología, Marañón Arana, Teodoro, Figueroa Clemente, Manuel Enrique, Cota, H., Doncel, J. L., García Novo, Francisco, Universidad de Sevilla. Departamento de Biología Vegetal y Ecología, Marañón Arana, Teodoro, Figueroa Clemente, Manuel Enrique, Cota, H., Doncel, J. L., and García Novo, Francisco

Abstract

Se han realizado inventarios de frecuencia de herbáceas {diez cuadros de 20 X 20 cm. en inventario) en 42 pastizales de dehesa de Badajoz y norte de Huelva, correspondientes a los principales tipos litológicos. La vegetación se estudió con el análisis de correspondencias. Se detectan seis tipos principales de pastizal que se han interpretado parcialmente con los datos de suelo y sustrato ahora disponibles. En comunicaciones posteriores se completará el análisis con ayuda de otras medidas ahora en realización.

Published
1977

45. Estudio ecológico de los pastizales de dehesa en la provincia de Badajoz. Tipificación preliminar de la vegetación empleando el análisis de correspondencias

Author

Marañón, Teodoro, Figueroa, Manuel E., Cota, H., Doncel, J. L., García Novo, F., Marañón, Teodoro, Figueroa, Manuel E., Cota, H., Doncel, J. L., and García Novo, F.

Abstract

[EN]: 42 grasslands of Badajoz and Huelva provinces (Western Spain) were studied recording plant species frequencies with 10 quadrats (20 X 20 cm.) randomly distributed over 2 X 2 m. plots taken under the crown on Quercus rotundifolia trees. Soil samples collected on every plot were analysed for pH, orgainic matter, P, Ca, K and Na. Frequency matrix (80 plant species X 42 plots) was analysed by the method know as "Analyse des Correspondences" (BENZECRI, 1973). The two main components (accounting for about 20% of the overall variation) separate plots into six recognizable groups (grassland types). A preliminary attempt to interpret those groups is made in terms of biotope (soil and substrate) differencies. The two main directions of variation found correspond to an eutrophization gradient (poor acidic versus rich basic soils) and to an erosion gradient (soil erosion versus pedogenesis). Secondary causes of variation are interpreted as due to lithology, climate and management. Further analysis of present data is currently under way., [ES]: Se han realizado inventarios de frecuencia de herbáceas (diez cuadros de 20 X 20 cm. en inventario) en 42 pastizales de dehesa de Badajoz y norte de Huelva, correspondientes a los principales tipos litológicos. La vegetación se estudió con el análisis de correspondencias. Se detectan seis tipos principales de pastizal que se han interpretado parcialmente con los datos de suelo y sustrato ahora disponibles. En comunicaciones posteriores se completará el análisis con ayuda de otras medidas ahora en realización.

Published
1977

46. Vandellós: A European site for ITER

Author

Alejaldre, C., Doncel, J., Angel Ibarra, Medrano, M., Brañas, B., García, A., Rodríguez-Rodrigo, L., Jiménez, J. A., Baibín, R., Mora, M. A. S., Alcalá, F., Díez, J. E., Prades, A., Sola, R., Sedano, L., Robles, B., Suáñez, A., Sáez, R., Varela, M., Sancho, C., Cabrera, J. A., Maisonnier, D., Benfatto, I., Coletti, A., Domínguez, M., Albisu, F., Buenaventura, A., Zárraga, B., Díaz-Llanos, M., Rogel, I., Martín Corrionero, J., Iturbe, R., Dierssen, G., and Rico, J.

47. Transport properties in the TJ-II flexible heliac

Author

Castejon, F., Ascasibar, E., Alejaldre, C., Alonso, J., Almoguera, L., Baciero, A., Balbin, R., Emilio Blanco, Blaumoser, M., Botija, J., Branas, B., Cappa, A., Carrasco, R., Cepero, Jr, Chmyga, Aa, Doncel, J., Dreval, Nb, Eguilior, S., Eliseev, L., Estrada, T., Fedyanin, O., Fernandez, A., Fuentes, C., Garcia, A., Garcia-Cortes, I., Goncalves, B., Guasp, J., Herranz, J., Hidalgo, A., Hidalgo, C., Jimenez, A., Kirpitchev, I., Khrebtov, Sm, Komarov, Ad, Kozachok, As, Krupnik, L., Lapayese, F., Likin, K., Liniers, M., Lopez-Bruna, D., Lopez-Fraguas, A., Lopez-Razola, J., Lopez-Sanchez, A., La Luna, E., Malaquias, A., Martin, R., Medrano, M., Melnikov, Av, Mendez, P., Mccarthy, Kj, Medina, F., Milligen, B., Nedzelskiy, Is, Ochando, M., Pacios, L., Pastor, I., Pedrosa, Ma, La Pena, A., Petrov, A., Portas, A., Romero, J., Rodriguez-Rodrigo, L., Salas, A., Sanchez, E., Sanchez, J., Sarksian, K., Schchepetov, S., Skvortsova, N., Tabares, F., Tafalla, D., Tribaldos, V., Varandas, Cfa, Vega, J., Zurro, B., Falconer, Is, Dewar, Rl, and Khachan, J.

48. Upgrade of the JET neutral beam heating system

Author

Ciric, D., primary, Jones, T.T.C., additional, Edwards, D.C., additional, Martin, D., additional, Bickley, A.J., additional, Brown, D.P.D., additional, Cox, S.J., additional, Dines, A.J., additional, Dobbing, J.A., additional, Milnes, J.J., additional, Shaw, S.R., additional, Stork, D., additional, Surrey, E., additional, Watson, M.J., additional, Young, D., additional, Young, I.D., additional, Bayetti, P., additional, and Doncel, J., additional

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50. Construction, commissioning and first results of the Spanish Stellarator TJ-II

Author

Blaumoser, M., primary, Alejaldre, C., additional, Almoguera, L., additional, Alonso, J., additional, Ascasibar, E., additional, Botija, J., additional, Carrasco, R., additional, Doncel, J., additional, Fraguas, A., additional, Garcia, A., additional, Kirpitchev, I., additional, Knaster, J., additional, Martinez, A., additional, Medrano, M., additional, Mendez, P., additional, Pacios, L., additional, de la Pena, A., additional, Qin, J., additional, Sanchez, J., additional, and Tabares, F., additional

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