Wobbling of a liquid column between unequal discs

One of the most puzzling results of an experiment on the stability of long liquid columns under microgravity, performed aboard Spacelab-D2 in 1993 and named STACO, aiming at the analysis of deformations of nearly cylindrical liquid columns under several mechanical disturbances, is revisited here. It corresponds to the unexplained breakage of an 85 mm long liquid bridge of low viscosity silicone oil, established between unequal discs of 30 and 28 mm, intended to counterbalance the expected deformation by residual acceleration found in previous flights, and left idle because the vibrations and oscillations to be applied afterwards were not started, for fear of premature breakage. A detailed image analysis is performed to extract the maximum amount of data, to be able to check against available theories for axisymmetric and non-axisymmetric deformations of a liquid column

Generación de conocimiento en las organizaciones apoyada por la Teoría General de Sistemas (Knowledge creation in the organizations aided by the General Systems Theory)

Abstract. This article pretends to make a linkage between the General Systems Theory and organizational knowledge generation, exposing the advantages of the use of this theory. Researches were used in order to let the reader to form his/her own criteria according the environment that is involved. Isolating the facts, not considering the organization to the decision making process will limit the development of the organizational knowledge, because al last, this knowledge will be losing when the individual are retiring from the organization. What is proposing is that the knowledge remains through a proper application of generation and retaining with constant renovation methods. Resumen. Este artículo pretende hacer una vinculación entre la Teoría de General de Sistemas y la generación de conocimiento organizacional, planteando las ventajas de la utilización de esta teoría. Hace uso de investigaciones que permiten que desde varias perspectivas el lector forme un criterio acorde con su entorno. El aislar los hechos, el no integrar a la organización para la toma de decisiones limitaría el desarrollo del conocimiento organizacional, que al final de cuentas, éste se va perdiendo en la medida que los individuos se van retirando. Lo que se plantea es que el conocimiento permanezca a través de una adecuada generación y retención aplicando métodos de constante renovación

Dynamic relationship analysis between NAFTA stock markets using nonlinear, nonparametric, non-stationary methods

This paper seeks to investigate the dynamic relationship between daily stock market indices in NAFTA countries from 8 November 1991 to 16 March 2018, using for the first time nonlinear, nonparametric, non-stationary methods. We apply two novel nonlinear, nonparametric, non-stationary dynamic correlation techniques rolling window Spearman correlation and wavelet coherence to study the relationships between the three pairwise comparisons. We apply a nonlinear, nonparametric causality test to four specific sub-periods and to the full period of these indices to check the direction of causality. Our results show the following: (1) the correlation between the indices increases from 2000 to 2011, but that correlation increase is interrupted around 2011/2012 and then falls noticeably, picking up again from 2015 onwards. (2) The pairs that show the lowest correlation are those involving the IPC. (3) The causality test reveals nonlinear bidirectional causality for all three indices and all the intervals analysed, indicating that there is a strong interrelationship between NAFTA members. These results are relevant to obtain a better understanding of the complex dynamical system formed by NAFTA stock markets and have direct implications for hedging and portfolio diversification policies. © 2019, Springer Nature B.V.JMPM was funded by a Basque Government post-doctoral fellowship

NonParRolCor: An R package for estimating rolling correlation for two regular time series

The R package NonParRolCor estimates rolling window correlations between two regular time series. The statistical significance estimated for the rolling correlation coefficients addresses effects due to multiple testing. This is done via Monte Carlo simulations by permuting one of the variables and keeping the other fixed. NonParRolCor uses parallel computing to improve computation time when statistical significance is estimated. NonParRolCor contains four functions for estimating and plotting the correlation coefficients for a single window-length or a band of window-lengths. NonParRolCor's functions are highly flexible, since they contain several parameters for controlling the estimation of correlation and the plot output. Some applications are presented to illustrate its use. © 2023 The Author(s)JMPM acknowledges to the Excellence Unit GECOS, Spain (reference number CLU-2019-03 ) at the Universidad de Salamanca for funding support. We would like to show our gratitude to the anonymous reviewers and the Editor Prof. Sobie whose comments and suggestions have been very helpful in improving this paper

Accelerated Simulation of P Systems on the GPU: A Survey

The acceleration of P system simulations is required increasingly, since they are at the core of model verification and validation processes. For this purpose, GPU computing is an alternative to more classic approaches in Parallel Computing. It provides a manycore platform with a level of high parallelism at a low cost. In this paper, we survey the developments of P systems simulators using the GPU, and analyze some performance considerations.Ministerio de Economía y Competitividad TIN2012- 37434Junta de Andalucía P08-TIC-0420

Analytical modelling of floating zone crystal growth

An analytical model for predicting the outer shape evolution of a crystal grown by the floating zone technique is developed. The analysis is axisymmetric and linear in the departure from a cylindrical evolution, thus it only applies to crystal growth under negligible external force fields (e.g. under microgravity), when the seed and feed sizes do not differ too much, and when radial deformations are not pronounced. In spite of these limitations, the analytical model clearly shows that, depending on the slenderness of the molten bridge, the processing may give rise to steady growth (after some transients) or just to a breakage by capillary force

Genetic characterisation of the murciano-granadina goat with microsatellites

It have been studied 92 animals of the Murciano-Granadina caprine breed with 22 microsatellites in order to get the genetic characterisation of this Spanish breed. Ovine and bovine microsatellites recommended by FAO, ISAG and other authors in the bibliography have been used. These markers were amplified by mean of the Polymerase Chain Reaction (PCR) technique and to get the size separation of the obtained fragments we have developed electrophoresis in polyacrylamide gel in an automatic sequencer ABI377XL. In future studies the genetic relationships between this breed an others Spanish and Latin-American caprine breeds will be established. The paternity and maternity have been checked with these microsatellites and this has been used to make a paternity panel with 10-12 markers and an a priori exclusion probability higher than 99,9 percent. This panel is useful to check paternity in this emblematic caprine breed from the South of Spain.Se estudian 92 animales pertenecientes a la raza caprina Murciano-Granadina, mediante 22 marcadores microsatélites con objeto de caracterizar esta raza peninsular española. Se han empleado microsatélites recomendados por la FAO, por la ISAG (International Society of Animal Genetics) y por la bibliografía para este tipo de estudios. Los microsatélites se han amplificado mediante la reacción en cadena de la polimerasa (PCR) y los fragmentos amplificados se han separado mediante electroforesis en un secuenciador automático ABI 377XL. En próximos estudios se establecerán las relaciones genéticas de esta raza con otras razas caprinas españolas e iberoamericanas. Se ha llevado a cabo también la comprobación de paternidades y maternidades con estos microsatélites, lo que ha servido para establecer una batería de 10-12 microsatélites con una probabilidad de exclusión a priori superior al 99,9 p.100 que puede resultar muy útil para realizar controles de filiación en esta raza caprina emblemática del sur de España