Procedimiento de comparación entre laboratorios de calibración basado en el criterio del error normalizado

Por medio de este artículo se explican los pasos que se recomiendan seguir para desarrollar una prueba de comparación entre laboratorios, la cual es muy usada en los laboratorios de calibración con el fin de dar cumplimiento a uno de los requisitos que la Norma Técnica Colombiana NTC ISO IEC 17025 [1] exige. En este artículo también se expone el criterio del error normalizado, el cual es uno de los criterios más utilizados en este tipo de actividades para determinar el estado de aceptación de cada uno de los laboratorios participantes

Algoritmo para la exploración de todos los valores posibles en el problema del agente viajero (TPS)

El siguiente artículo muestra algunas aplicaciones empleadas para probar soluciones acerca del problema del agente viajero y busca mostrar ejemplos de algoritmos desarrollados para este fin, en esta primera parte el de fuerza bruta y en la siguiente los basados en algoritmos heurísticos

Algoritmo para la exploración de todos los valores posibles en el problema del agente viajero (TPS)

El siguiente artículo muestra algunas aplicaciones empleadas para probar soluciones acerca del problema del agente viajero y busca mostrar ejemplos de algoritmos desarrollados para este fin, en esta primera parte el de fuerza bruta y en la siguiente los basados en algoritmos heurísticos

Elaboración de cartas de control x barra – s en el laboratorio de metrología de variables eléctricas de la universidad tecnológica de pereira

En el presente artículo se explican uno a uno los pasos que se deben seguir al realizar una carta de control x barra – s con los datos obtenidos de la prueba de aptitud del equipo patrón del Laboratorio de Metrología de Variables Eléctricas de la UTP y además se elabora un ejemplo completo con el objetivo de ilustrar mejor la forma en que se hace este procedimiento

Elaboración de cartas de control x barra – s en el laboratorio de metrología de variables eléctricas de la universidad tecnológica de pereira

En el presente artículo se explican uno a uno los pasos que se deben seguir al realizar una carta de control x barra – s con los datos obtenidos de la prueba de aptitud del equipo patrón del Laboratorio de Metrología de Variables Eléctricas de la UTP y además se elabora un ejemplo completo con el objetivo de ilustrar mejor la forma en que se hace este procedimiento

Elaboración de cartas de control x barra – s en el laboratorio de metrología de variables eléctricas de la universidad tecnológica de pereira

En el presente artículo se explican uno a uno los pasos que se deben seguir al realizar una carta de control x barra – s con los datos obtenidos de la prueba de aptitud del equipo patrón del Laboratorio de Metrología de Variables Eléctricas de la UTP y además se elabora un ejemplo completo con el objetivo de ilustrar mejor la forma en que se hace este procedimiento

Shape of the oxygen abundance profiles in CALIFA face-on spiral galaxies

Astronomy & Astrophysics 587 (2016): A70 reproduced with permission from Astronomy & AstrophysicsWe measured the gas abundance profiles in a sample of 122 face-on spiral galaxies observed by the CALIFA survey and included all spaxels whose line emission was consistent with star formation. This type of analysis allowed us to improve the statistics with respect to previous studies, and to properly estimate the oxygen distribution across the entire disc to a distance of up to 3-4 disc effective radii (re). We confirm the results obtained from classical H ii region analysis. In addition to the general negative gradient, an outer flattening can be observed in the oxygen abundance radial profile. An inner drop is also found in some cases. There is a common abundance gradient between 0.5 and 2.0 re of αO/H =-0.075 dex/re with a scatter of σ = 0.016 dex/re when normalising the distances to the disc effective radius. By performing a set of Kolmogorov-Smirnov tests, we determined that this slope is independent of other galaxy properties, such as morphology, absolute magnitude, and the presence or absence of bars. In particular, barred galaxies do not seem to display shallower gradients, as predicted by numerical simulations. Interestingly, we find that most of thegalaxies in the sample with reliable oxygen abundance values beyond ~2 effective radii (57 galaxies) present a flattening of the abundance gradient in these outer regions. This flattening is not associated with any morphological feature, which suggests that it is a common property of disc galaxies. Finally, we detect a drop or truncation of the abundance in the inner regions of 27 galaxies in the sample; this is only visible for the most massive galaxiesWe acknowledge financial support from the Spanish Ministerio de Economía y Competitividad (MINECO) via grant AYA2012-31935, and from the “Junta de Andalucía” local government through the FQM-108 project. We also acknowledge support to the ConaCyt funding program 180125. Y.A. acknowledges fi- nantial support from the Ramón y Cajal programme (RyC-2011-09461). Y.A. and A.I.D. acknowledge support from the project AYA2013-47742-C4-3-P from the Spanish MINECO, as well as the “Study of Emission-Line Galaxies with Integral-Field Spectroscopy” (SELGIFS) programme, funded by the EU (FP7- PEOPLE-2013-IRSES-612701). Support for L.G. is provided by the Ministry of Economy, Development, and Tourism’s Millennium Science Initiative through grant IC120009, awarded to The Millennium Institute of Astrophysics, MAS. LG acknowledges support by CONICYT through FONDECYT grant 3140566. R.M.G.D. acknowledges support from the Spanish grant AYA2014-57490-P, and from the “Junta de Andalucía” P12-FQM2828 project. RAM thanks the Spanish program of International Campus of Excellence Moncloa (CEI). IM and A.d.O. acknowledge support from the Spanish MINECO grant AYA2013-42227P. JMA acknowledges support from the European Research Council Starting Grant (SEDmorph, P.I. V. Wild). Support for MM has been provided by DGICYT grant AYA2013-47742-C4-4-P. PSB acknowledges support from the Ramón y Cajal programme, grant ATA2010-21322-C03-02 from the Spanish MINECO. CJW acknowledges support through the Marie Curie Career Grant Integration 30391

Shape of the oxygen abundance profiles in CALIFA face-on spiral galaxies

Y.A. acknowledges financial support from the Ramón y Cajal programme (RyC-2011-09461). Y.A. and A.I.D. acknowledge support from the project AYA2013-47742-C4-3-P from the Spanish MINECO, as well as the “Study of Emission-Line Galaxies with Integral-Field Spectroscopy” (SELGIFS) programme, funded by the EU (FP7-PEOPLE-2013-IRSES-612701). Support for L.G. is provided by the Ministry of Economy, Development, and Tourism’s Millennium Science Initiative through grant IC120009, awarded to The Millennium Institute of Astrophysics, MAS. LG acknowledges support by CONICYT through FONDECYT grant 3140566. R.M.G.D. acknowledges support from the Spanish grant AYA2014-57490-P, and from the “Junta de Andalucía” P12-FQM2828 project. RAM thanks the Spanish program of International Campus of Excellence Moncloa (CEI). IM and A.d.O. acknowledge support from the Spanish MINECO grant AYA2013-42227P. JMA acknowledges support from the European Research Council Starting Grant (SEDmorph, P.I. V. Wild). Support for MM has been provided by DGICYT grant AYA2013-47742-C4-4-P. PSB acknowledges support from the Ramón y Cajal programme, grant ATA2010-21322-C03-02 from the Spanish MINECO. CJW acknowledges support through the Marie Curie Career Grant Integration 303912.We measured the gas abundance profiles in a sample of 122 face-on spiral galaxies observed by the CALIFA survey and included all spaxels whose line emission was consistent with star formation. This type of analysis allowed us to improve the statistics with respect to previous studies, and to properly estimate the oxygen distribution across the entire disc to a distance of up to 3-4 disc effective radii (re). We confirm the results obtained from classical H ii region analysis. In addition to the general negative gradient, an outer flattening can be observed in the oxygen abundance radial profile. An inner drop is also found in some cases. There is a common abundance gradient between 0.5 and 2.0 re of αO/H =-0.075 dex/re with a scatter of σ = 0.016 dex/re when normalising the distances to the disc effective radius. By performing a set of Kolmogorov-Smirnov tests, we determined that this slope is independent of other galaxy properties, such as morphology, absolute magnitude, and the presence or absence of bars. In particular, barred galaxies do not seem to display shallower gradients, as predicted by numerical simulations. Interestingly, we find that most of thegalaxies in the sample with reliable oxygen abundance values beyond ~2 effective radii (57 galaxies) present a flattening of the abundance gradient in these outer regions. This flattening is not associated with any morphological feature, which suggests that it is a common property of disc galaxies. Finally, we detect a drop or truncation of the abundance in the inner regions of 27 galaxies in the sample; this is only visible for the most massive galaxies.Publisher PDFPeer reviewe

Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016