3,174 research outputs found
OPTIMAL REGULATION AND GROWTH IN A NATURAL-RESOURCE-BASED ECONOMY
This paper develops a two-sector model for a renewable natural resource based economy. Pareto efficient results show the optimal harvesting rate that allows for sustained long-run optimal growth, which is upper-bounded by the biological rate of reproduction. Regulation prevents from resource over-exploitation and exhaustion which arise under open access. The Ramsey policy allowing the competitive economy to reach the first-best solution, leads the government to tax harvesting activity from firms and distribute the receipts among households. In the short-run the tax is variable. In the long-run, the lower the intrinsic rate of reproduction the higher the constant unit tax on the resource use.Natural Resources, Efficiency, Open Access, Ramsey Regulation, Growth.
El termómetro de globo en estudios de confort y medioambiente en los edificios
The reasons for the inferior performance of many existing buildings and associated energy systems are diverse, but an important part-cause is insufficient attention to the influence of occupant behaviour. In smart buildings it is necessary to allow for the integration of human behaviour in the HVAC system. In addition, many researchers are limited in their investigation by not having low cost tools that can provide information for their studies. This article is a review of the present state of art about the globe thermometer. It describes how to build your own globe temperature sensor and describes experiments that illustrate the feasibility of using a black globe thermometer with 40 mm diameter.Las razones del rendimiento inferior de muchos de los edificios actuales y sus sistemas energéticos relacionados son diversas y estas son en una parte importante causada por una atención insuficiente a la influencia del comportamiento de los ocupantes. En los edificios inteligentes es necesario implementar nuevas oportunidades para integrar el comportamiento humano en el sistema de climatización. Además, muchos investigadores están limitados en su investigación al no contar con herramientas de bajo coste que puedan proporcionar información a sus estudios. En este artículo se presenta una revisión del estado actual del arte sobre el termómetro de globo, se describe cómo construir su propio sensor de temperatura de globo y los experimentos descritos ilustran la viabilidad de utilizar un termómetro de globo negro con 40 mm de diámetro
Análisis observacional del lanzamiento de balonmano en la fase de contraataque de las selecciones finalistas del mundial de Qatar 2015
Resumen basado en el de la publicaciónSe pretende analizar la efectividad de los lanzamientos de balonmano en la fase de contraataque en el alto rendimiento. Para ello se analizaron 10 partidos disputados por las dos selecciones finalistas del Mundial de Qatar en el año 2015 (Qatar y Francia). El análisis se realizó mediante una metodología observacional, donde se evaluaron diferentes parámetros relacionados con el lanzamiento en balonmano: modelo del lanzamiento (tipo), la distancia, la posición/ángulo y la fase dentro del contraataque (ciclo del juego). El análisis descriptivo de los resultados muestra que existe una alta efectividad de los lanzamientos que se realizan en la fase de contraataque. Los equipos tienden a realizar un mayor número de lanzamientos durante los contraataques de la primera parte del partido. En cuanto a las características del lanzamiento durante esta fase, hay que resaltar que se realiza en la 1ª oleada, en suspensión, a poca distancia de la portería y sobre todo desde zonas centrales del campo. Estos resultados se han discutido con estudios similares.ES
Relative age effect in handball players of Spain
This study analyzes the effect of relative age in the selection process of handball players for licensed club teams in the Murcia region and the Murcia Regional Handball teams. To this end we studied gender, date of birth and player category in a total of 846 handball players (762 of them in licensed clubs from the Murcia Regional Handball Federation, henceforth FBRM and 84 players in Murcia regional teams respectively) in the children’s, junior and youth categories. Comparisons were made and differences were analyzed with χ2 and Z tests and the Bonferroni correction. The analysis of results according to quarter and semester of birth revealed statistically significant differences both for licensed clubs and for Murcia Regional handball team players. The gender and player category analysis showed statistically significant results only in the case of category in regional teams. Thus RAE is confirmed in the samples analyzed, this effect being stronger amongst regional team players
Analysis of the presence of sustainability in Higher Education Degrees of the Spanish university system
This paper analyzes the extent to which sustainability is present in the
curricula of the 16 Education Degree programs belonging to the
EDINSOST project: 6 Early Childhood Education Degrees, 7 Primary
Education Degrees, 2 Pedagogy Degrees and 1 Social Education Degree.
The results obtained suggest that sustainability is present in all Degrees,
but not uniformly so. A great disparity is observed in the number of
subjects that develop sustainability, with an average of 22.63 subjects
per Degree. The competency most present is the
‘
Application of ethical
principles related to the values of sustainability in personal and
professional behaviors,
’
while the least present is
‘
Sustainable use of
resources and prevention of negative impacts on the natural and social
environment.
’Sustainability is not developed uniformly in the different
universities either. Three universities (UAM, UCA and UIC) develop
sustainability competencies at 100%, while others such as the USAL do
so at only 50
Gravitational production of scalar dark matter
We investigate the gravitational production of scalar dark matter particles during the inflationary and reheating epochs. The oscillatory behavior of the curvature scalarRduring the reheating phase generates two different enhancement mechanisms in the particle production. On the one hand, as it has been already discussed in previous works, it induces tachyonic instabilities in the field which are the dominant enhancement mechanism for light masses. On the other hand, we have found that it also provokes a resonant effect in the ultraviolet region of the spectrum which becomes dominant for masses in the range 10(9)GeV to 10(13)GeV. We have developed an analytical approximation to describe this resonance effect and its consequences on the ultraviolet regime. Once we have calculated the theoretical gravitational production, we constrain the possible values of the phenomenological field parameters to be considered as a dark matter candidate. We do so by comparing the theoretically predicted abundance with the observed one and ensuring that the theoretical prediction does not lead to overproduction. In particular, we find that there is a region of intermediate masses that is forbidden as they would lead to overproduction
Airflow patterns through a sliding door during opening and foot traffic in operating rooms
Producción CientíficaIt is common practice for operating rooms (OR) to have more pressure than the adjacent enclosures. This is to prevent the entry of potentially contaminated air and the consequent risk of wound infection. However, when the OR door is opened the pressure difference between the two areas disappears and can cause containment failures. If a person enters or leaves the OR during door operation, additional perturbations are also generated in the airflow pattern in the doorway. In this paper, instantaneous airflows are measured during the passage of a person through a sliding door in a real OR with the HVAC system working under operating conditions. An ultrasonic anemometer that measures the magnitude and direction of the instantaneous air velocity in the doorway is used. Results show that, even though the OR has a sliding door and an initial overpressure of 20 Pa, together with what is, a priori, a good HVAC system control strategy, a small volume of air enters the OR during a cycle of door opening and closing even without the passage of a person. Furthermore, if a person walks through the door the volume of air entering the OR is higher, especially if the person enters the OR. © 2016 Elsevier LtdMinistry of Economy and Competiveness project DPI2014-55357-C2-1-R cofinanced by the European Regional Development Fund (ERDF)
Aceros al molibdeno sinterizados con gradiente funcional
Las propiedades que se solicitan a las piezas y productos exigen, la mayoría de las veces, una combinación de materiales que respondan a requerimientos específicos en función de su posición. La fabricación de materiales compuestos y materiales con gradiente funcional proporciona grandes posibilidades de respuesta a las necesidades demandas, tanto de satisfacción de requerimientos como de reducción de materias primas necesarias. En este sentido, satisfacer las propiedades demandadas, de manera localizada geométricamente, puede suponer un ahorro de materias primas y de los residuos relacionados en su fabricación. En el presente estudio de la sinterización a 1120 ºC de un compacto de dos aceros de diferentes composiciones (un acero con un 0,3 % C y un 2 % de cobre y un acero al molibdeno con un 0,7 % carbono y un 2 % de cobre) ofrece unas posibilidades muy atractivas de eficiencia, al reducir en el interior la composición que se requiere en la superficie de las piezas. Se han caracterizado las propiedades mecánicas de este acero sinterizado con gradiente funcional: densidad, variación dimensional, durezas y resistencia mecánica; ilustradas con el análisis de imagen mediante microscopía óptica y electrónica de barrido
Impact of the Method Used to Select Gas Exchange Data for Estimating the Resting Metabolic Rate, as Supplied by Breath-by-Breath Metabolic Carts
The method used to select representative gas exchange data from large datasets influences
the resting metabolic rate (RMR) returned. This study determines which of three methods yields the
lowest RMR (as recommended for use in human energy balance studies), and in which method the
greatest variance in RMR is explained by classical determinants of this variable. A total of 107 young
and 74 middle-aged adults underwent a 30 min RMR examination using a breath-by-breath metabolic
cart. Three gas exchange data selection methods were used: (i) steady state (SSt) for 3, 4, 5, or 10 min,
(ii) a pre-defined time interval (TI), i.e., 6–10, 11–15, 16–20, 21–25, 26–30, 6–25, or 6–30 min, and (iii)
“filtering”, setting thresholds depending on the mean RMR value obtained. In both cohorts, the RMRs
yielded by the SSt and filtering methods were significantly lower (p < 0.021) than those yielded by the
TI method. No differences in RMR were seen under the different conditions of the SSt method, or of
the filtering method. No differences were seen between the methods in terms of the variance in RMR
explained by its classical determinants. In conclusion, the SSt and filtering methods return the lowest
RMRs and intra-measurement coefficients of variation when using breath-by-breath metabolic carts.This study was supported by the Spanish Ministry of Economy and Competitiveness via the Fondo
de Investigación Sanitaria del Instituto de Salud Carlos III (PI13/01393), Retos de la Sociedad (DEP2016-79512-R) and
European Regional Development Funds (ERDF), the Spanish Ministry of Education (FPU 15/04059 and FPU14/04172),
the Fundación Iberoamericana de Nutrición (FINUT), the Redes Temáticas de Investigación Cooperativa RETIC (Red
SAMID RD16/0022), the AstraZeneca HealthCare Foundation, the University of Granada Plan Propio de Investigación
2016 Excellence Actions: Unit of Excellence on Exercise and Health (UCEES) and Plan Propio de Investigación 2018
and 2019 Programa Contratos-Puente and Plan Propio de Investigación 2018 Programa Perfeccionamiento de Doctores, and
the Junta de Andalucía, Consejería de Conocimiento, Investigación y Universidades (ERDF: ref. SOMM17/6107/UGR),
and the Fundación Alfonso Martín Escudero
Interpolation subspaces of L^1 of a vector measure and norminequalities for the integration operator
[EN] Let m be a Banach space valued measure. We study some domination
properties of the integration operator that are equivalent to the existence
of Banach ideals of L1(m) that are interpolation spaces. These domination
properties are closely connected with some interpolated versions of summing
operators, like (p, è)-absolutely continuous operators.J.M. Calabuig was supported by Ministerio de Ciencia e Innovacion (project MTM2008-04594) and Generalitat Valenciana (project GV/2009/102). J. Rodriguez was supported by Ministerio de Ciencia e Innovacion (project MTM2008-05396) and Fundacion Seneca (project 08848/PI/08). E.A. Sanchez-Perez was supported by Ministerio de Ciencia e Innovacion (project MTM2009-14483-C02-02). The authors were also supported by Universidad Politecnica de Valencia (project PAID-06-08-3093).Calabuig Rodriguez, JM.; Rodríguez Ruiz, J.; Sánchez Pérez, EA. (2012). Interpolation subspaces of L^1 of a vector measure and norminequalities for the integration operator. Contemporary Mathematics. 561:155-163. https://doi.org/10.1090/conm/561/11113S15516356
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