9,107 research outputs found
Evolution Strategies in Optimization Problems
Evolution Strategies are inspired in biology and part of a larger research
field known as Evolutionary Algorithms. Those strategies perform a random
search in the space of admissible functions, aiming to optimize some given
objective function. We show that simple evolution strategies are a useful tool
in optimal control, permitting to obtain, in an efficient way, good
approximations to the solutions of some recent and challenging optimal control
problems.Comment: Partially presented at the 5th Junior European Meeting on "Control
and Information Technology" (JEM'06), Sept 20-22, 2006, Tallinn, Estonia. To
appear in "Proceedings of the Estonian Academy of Sciences -- Physics
Mathematics
A symmetric quantum calculus
We introduce the -symmetric difference derivative and the
-symmetric N\"orlund sum. The associated symmetric quantum
calculus is developed, which can be seen as a generalization of the forward and
backward -calculus.Comment: Submitted 26/Sept/2011; accepted in revised form 28/Dec/2011; to
Proceedings of International Conference on Differential & Difference
Equations and Applications, in honour of Professor Ravi P. Agarwal, to be
published by Springer in the series Proceedings in Mathematics (PROM
Parenting style: influence on gifted children psychological adjustment
Este trabajo se centra en las influencias positivas y negativas de la práctica educativa que los padres ejercen sobre el desarrollo de los niños con altas capacidades. El resultado de este estudio teórico muestra que las familias cuyas caracterÃsticas esenciales están basadas en una dinámica de funcionamiento en la que priman la armonÃa y la coherencia se asocian tanto al desarrollo óptimo intelectual y de la autoestima como al adecuado funcionamiento emocional e intelectual. En contraste, las familias en las que la falta de coherencia y la existencia de una dinámica de funcionamiento caracterizada por bajos niveles de comunicación, afecto y control del comportamiento se asocian a la aparición de comportamientos de riesgo. De acuerdo con la literatura existente, las prácticas educativas más efectivas para el ajuste y bienestar de niños y adolescentes son las autoritativas. En el caso de los niños con altas capacidades, la mayorÃa de los padres se muestran acordes con estas prácticas de crianza aunque en algunos casos se han encontrado diferencias en las pautas de actuación de madres y padres. Los determinantes parentales que potencian el ajuste positivo de los hijos con altas capacidades son: nivel intelectual, nivel educativo y rendimiento académico alto, y en ausencia de estas caracterÃsticas, interés de los padres hacia la educación y el aprendizaje.This paper focused on influence of parenting practice on gifted children´s development. The result of this study showed that harmony and coherent families are associated both to self-stem, effective intellectual development and social and emotional functioning. In contrast, family discord relates to risk behaviour. According to literature, the most effective parenting practice for children development is authoritative, In gifted children case, most of the parents showed educative patterns framed in the authoritative parenting style although in some cases it was found differences between mother and father. Parents determinants making possible positive adjustement in their gifted children are: high intellectual level, high school achievement and high level of school performance. In absence of this, parent´s high interest on education and learning act as a substitute of these last cognitive and educational characteristics.peerReviewe
Latinos in the South: A Glimpse of Ongoing Trends and Research
Since the late 1980s, there has been a tremendous amount of reshifting in the Latino population of the United States. This movement has resulted in the increasing settlement of Latinos in areas of the country that have historically not had Latino populations, particularly in rural settings. In particular, areas in the South and Midwest have experienced significant growth in the Latino population. This article provides an overview of this growth in the South using data from the 1990 and 2000 censuses. In addition, the article provides a brief description of the accompanying articles that are featured in this special issue on Latinos in the South. Finally, the article discusses the implications of the articles contained in the special issue and provides direction for future research
Successful organizational learning in the management of agricultural research and innovation: The Mexican produce foundations
"Since the 1980s, developing countries' agriculture has become more complex and diversified. In general, the public research and extension institutions in these countries were criticized for not participating in the emergence of the most dynamic agricultural markets. In recent years, many of these institutions have struggled to adapt to the new environment but they could not overcome the hurdles posed by organizational rigidities, strict public regulations, deteriorating human capital, shrinking budgets and a model of science that hampered their integration into dynamic innovation processes. In general, developing countries applied similar agricultural research policies: separation of financing and implementation of research, reductions in direct budgetary allocations to research and extension institutions, elimination or major reduction of public extension, and introduction of competitive grants programs to induce a transformation of research organizations. Strong anecdotal information suggests that these policies had limited impact on the quality and pertinence of research, and on the performance of the public research institutions. Using a different set of instruments, the Mexican Produce Foundations (PF) had major and diverse impacts on the agricultural innovation and research systems. These impacts resulted mostly from activities the PF introduced as they learned to manage funds for research and extension, and to a lesser extent from the activities they were created for, i.e., manage a competitive fund for agricultural research and extension. The PF were able to introduce these activities because they developed strong abilities to learn, including identifying knowledge gaps and defining strategies to fill them. The questions this report seeks to answer are how an organization that manages public funds for research and extension could sustain organizational innovations over extended periods, and how it could learn and adapt to maximize its impact on the agricultural innovation system. Previous studies found that human resources, organizational cultures and governance structures are three of the most important factors influencing institutional change and innovative capabilities. Despite their importance, these factors have been largely neglected in the literature on agricultural research and extension policies. This document analyzes what role these factors played in the Mexican experience." from textAgricultural research, Agricultural innovation, Developing countries,
Efecto inmediato del vendaje dynamic tape® sobre la torsión tibial externa dolorosa en un jugador de fútbol
The Brightest Cluster Galaxy in Abell 85: The Largest Core Known so far
We have found that the brightest cluster galaxy (BCG) in Abell~85, Holm 15A,
displays the largest core so far known. Its cusp radius, kpc (), is more than 18 times
larger than the mean for BCGs, and kpc larger than A2261-BCG, hitherto
the largest-cored BCG (Postman, Lauer, Donahue, et al. 2012) Holm 15A hosts the
luminous amorphous radio source 0039-095B and has the optical signature of a
LINER. Scaling laws indicate that this core could host a supermassive black
hole (SMBH) of mass . We
suggest that cores this large represent a relatively short phase in the
evolution of BCGs, whereas the masses of their associated SBMH might be set by
initial conditions.Comment: 14 pages, 3 figure, 2 tables, accepted for publication in ApJ Letters
on October 6th, 2014, replacement of previous manuscript submitted on May
30th, 2014 to astro-p
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