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Search Results: 1 - 10 of 198278 matches for " Joaquín Santisteban Urquiza "
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The excellence of the metaheurístics and the problems of optimization. La excelencia de las metaheurísticas y los problemas de optimización.
Joaquín Santisteban Urquiza
Revista Cubana de Ciencias Informáticas , 2012,
Abstract: Many are the problems that are taken to investigation centers so that they are resolved. A class of these problems is the denominated problems of optimization. The peak of these problems began from the second world war when the resources began to be scare. The problems of optimization are of vital importance because they are presentin all the spheres in the human being's life. Whenever a person is traced objectives in the life, needs of actions to be able to carry out them and these actions should complete necessary restrictions so that they can be adapted to the outlined objective. With the result that whenever we trace ourselves a practical objective you can model through models of optimization. The strategies metaheurístics are algorithms designed for the resolution of these problems and they acquire importance when an exact method of resolution doesn't exist or this it requires a lot of time of calculation or memory, When one doesn't need the good solution, When the data are few reliable or when the pattern is a simplification of the reality, When limitations of time, space forces the employment of methods of fast answer, Like intermediate step in the application of another algorithm. Another important advantage of these strategies is also that they allow a bigger flexibility for the handling of the problem with relationship to the exact methods. Muchos son los problemas que son llevados a centros de investigación para que sean resueltos. Una clase de estos problemas son los denominados problemas de optimización. El auge de estos problemas comenzó desde la segunda guerra mundial cuando los recursos comenzaron a escasear. Los problemas de optimización son de vital importancia porque están presentes en todas las esferas en la vida del ser humano. Siempre que una persona se trace objetivos en la vida, necesita de acciones para poder realizarlos y estas acciones deben cumplir restricciones necesarias para obtener el objetivo planteado. De ahí que siempre que nos tracemos un objetivo práctico se puede modelar a través de modelos de optimización. Las estrategias metaheurísticas son algoritmos dise ados para la resolución de estos problemas y adquieren importancia cuando no existe un método exacto de resolución o este requiere mucho tiempo de cálculo o memoria, cuando no se necesita la solución óptima, cuando los datos son pocos fiables o cuando el modelo es una simplificación de la realidad, cuando limitaciones de tiempo, espacio obliguen el empleo de métodos de rápida respuesta, como paso intermedio en la aplicación de otro algoritmo. Además otra impo
Explosions and seismic phenomena based on exciting of acoustic-electromagnetic waves  [PDF]
S. Koshevaya, V. Grimalsky, G. Urquiza, M. Tecpoyotl, A. Kotsarenko, V. Yutsis, N. Makarets
Natural Science (NS) , 2012, DOI: 10.4236/ns.2012.428086
Abstract: During earthquakes and strong underground explosions it is possible to observe two different effects. The first one is connected with the destruction of media, and this causes acoustic and later hybrid acoustic-electromagnetic waves in an epicenter in the atmosphere and in the ionosphere. Another one is connected with cracks in crystals of rocks, which seems more interesting, because it is possible to recognize the natural earthquakes and industrial explosions. In the first effects due to nonlinear elastic modules the acoustic waves move through the lithosphere and transform their spectra from VLF (very low frequencies ~ 1 - 10 kHz) at the depth of about 30 km into the lower part of ELF (extremely low frequencies, ~ 3 Hz - 1 kHz) on the Earth’s surface, then they pass the atmosphere and penetrate into the ionosphere. During the nonlinear acoustic passage through the atmosphere and the ionosphere, the spectrum transforms from ELF into ULF (ultra low frequencies, < 1 Hz) range. In this review article the classification of spectrum and analysis of two cases of the destruction of rocks in the lithosphere is presented. The rocks possess piezoelectric and piezomagnetic properties. In this case the electromagnetic emission is excited by the fracturing in plates of crystals. The difference of emission from piezoelectric and magnetic plates in cases of industrial explosions and natural seismic events including volcanic phenomena gives a possibility to analyze the method of its identification. The consideration is based on the model of the plate of a finite size with an uniformly moving crack.
Reunión Anual de la Associación Norteamericana de Evaluación (AEA) "The territory ahead: Foundations and frontiers". Orlando, Florida. 2-6 de noviembre de 1999
Nú?ez Urquiza Rosa María
Salud Pública de México , 2000,
Abstract:
From generation to generation: The health and well-being of children on immigrant families
Nú?ez Urquiza Rosa María
Salud Pública de México , 1999,
Abstract:
Rese a: Las obras completas de Leo Strauss
Joaquín Abellán
Foro Interno : Anuario de Teoría Política , 2005,
Abstract:
Tourist satisfaction indices. A critical approach
Joaquín Alegre,Joaquín Alegre
Investigaciones Regionales , 2009,
Abstract: In literature, analyses can be found of the competitiveness of internationaltourist destinations, based on tourist satisfaction with different attributes. However,most of these analyses do not use one single measure to make a global assessment,which makes it difficult to compare destinations. The aim of this paper is twofold.First, some alternatives that can be used as a synthetic index of tourist satisfaction arediscussed. Second, the indices that are proposed are used to analyse a group of rivaldestinations for the European sun and sand tourism market. From the results that areobtained, the advantages of each of the proposed indices are discussed.
Consumo calórico, estado nutricional materno, y retraso del crecimiento intrauterino
Martins, Eliana Bender;Nú?ez Urquiza, Rosa María;
Cadernos de Saúde Pública , 2003, DOI: 10.1590/S0102-311X2003000100031
Abstract: to explore the association between low caloric intake during pregnancy and intrauterine growth retardation (iugr), a case-control study with 264 cases and 892 controls was conducted in three maternity hospitals in mexico city from january to august 1995. nutritional information on pregnancy was recorded using a previously validated food frequency questionnaire. after adjusting for other known maternal risk factors in the non-conditional logistic regression analysis, for the total sample, caloric intake did not present a direct effect on iugr (or: 0.99; ci 95%: 0.99-1.00). however the odds ratios were as follows for women: with low pre-gestational weight (or: 2.31; ci 95%: 1.59-3.36), in first gestation (or: 1.72; ci 95%: 1.18-2.51), with low birth weight infants (or: 3.54; ci 95%: 1.93-6.46), and presenting hypertension during pregnancy (or: 1.61; ci 95%: 1.00-2.59).
Consumo calórico, estado nutricional materno, y retraso del crecimiento intrauterino
Martins Eliana Bender,Nú?ez Urquiza Rosa María
Cadernos de Saúde Pública , 2003,
Abstract: Para conocer la asociación entre el consumo de energía en el embarazo y el retraso del crecimiento intrauterino (RCIU), se llevó a cabo un estudio de caso-cohorte en tres hospitales de maternidad de la ciudad de México, entre enero y agosto de 1995. De un total de 4.000 partos que ocurrieron en este período, nos referimos en este estudio a los resultados de un análisis de 264 casos de RCIU y 892 controles. Se procedió a un análisis de regresión logística no condicionada, en el que también se ajustaron los factores maternos potencialmente proclives a la confusión. Para el total de los casos no se observó un efecto directo del consumo de energía en el RCIU (RM: 0,99; IC 95%: 0,99-1,00). Sin embargo, entre las mujeres que comenzaron el embarazo con un peso de 50 kilos o menos, el consumo de energía en relación a RCIU mostró una razón de momios de 2,31 (RM: 2,31; IC 95%: 1,59-3,36); para las mujeres primigestas de 1,72 (RM: 1,72; IC 95%: 1,18-2,51; en aquellas con antecedente de bajo peso al nacer de 3,54 (RM: 3,54; IC 95%: 1,93-6,46) y para aquellas que presentaron tensión arterial alta en el embarazo de 1,61 (RM: 1,61; IC 95%: 1,00-2,59).
The Birth of a New Party: Podemos, a Hurricane in the Spanish Crisis of Trust  [PDF]
Jose M. Pavía, Anselm Bodoque, Joaquín Martín
Open Journal of Social Sciences (JSS) , 2016, DOI: 10.4236/jss.2016.49008
Abstract: A significant number of European electors are turning their backs on traditional main-stream parties. European party systems are being challenged by an increasing number of (new) radical parties, which defied the Christian-social democrat alternation that has dominated Western European countries for decades. In Spain, a political earthquake started after the 2014 European Parliament election. In the context of the worst global economic crisis in the last 80 years (which in Spain is also a social, political and institutional crisis), a party called Podemos won 7.9% of votes and five MEPs, significantly altering the traditional balance of the Spanish party system. This paper studies the causes of the support received by Podemos on 2014 EP elections, dissects its political strategy and analyses the characteristics of the electorate that made possible the birth of this new party. The analysis, which is illustrated using micro-data of twelve surveys, discloses Podemos political agenda.
Sentido originario y traducción moderna apropiada del Peri Politeian(Sobre la Constitución [DK 85 B 1]) De Trasímaco
Meabe,Joaquín E.;
Enfoques , 2008,
Abstract: this paper puts together some of the consideration of the signification and theoretical value of . the first part of the paper reviews the theoretical implication of text and his context. the second part presents the original text and a new spanish lineal translation.
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