Estimate of the (R)USLE rainfall erosivity factor from monthly precipitation data in mainland Spain

The need for continuous recording rain gauges makes it difficult to determine the rainfall erosivity factor (R-factor) of the (R)USLE model in areas without good temporal data coverage. In mainland Spain, the Nature Conservation Institute (ICONA) determined the R-factor at few selected pluviographs, so simple estimates of the R-factor are definitely of great interest. The objectives of this study were: (1) to identify a readily available estimate of the R-factor for mainland Spain; (2) to discuss the applicability of a single (global) estimate based on analysis of regional results; (3) to evaluate the effect of record length on estimate precision and accuracy; and (4) to validate an available regression model developed by ICONA. Four estimators based on monthly precipitation were computed at 74 rainfall stations throughout mainland Spain. The regression analysis conducted at a global level clearly showed that modified Fournier index (MFI) ranked first among all assessed indexes. Applicability of this preliminary global model across mainland Spain was evaluated by analyzing regression results obtained at a regional level. It was found that three contiguous regions of eastern Spain (Catalonia, Valencian Community and Murcia) could have a different rainfall erosivity pattern, so a new regression analysis was conducted by dividing mainland Spain into two areas: Eastern Spain and plateau-lowland area. A comparative analysis concluded that the bi-areal regression model based on MFI for a 10-year record length provided a simple, precise and accurate estimate of the R-factor in mainland Spain. Finally, validation of the regression model proposed by ICONA showed that R-ICONA index overpredicted the R-factor by approximately 19%.La necesidad de disponer de un registro continuo de la precipitación dificulta el cálculo del índice de erosión pluvial (factor R) del modelo (R)USLE en zonas sin un buen registro temporal. En la España peninsular, el Instituto para la Conservación de la Naturaleza (ICONA) determinó el factor R en un reducido número de pluviógrafos, por lo que es de gran interés disponer de una herramienta que permita estimar el factor R de manera sencilla. Los objetivos de este estudio fueron: (1) identificar un estimador del factor R en la España peninsular; (2) discutir la aplicabilidad de un único modelo de estimación global a partir de los resultados obtenidos a nivel regional; (3) analizar el efecto de la longitud del intervalo de cálculo en la precisión y exactitud de las estimaciones; y (4) evaluar el modelo de regresión disponible propuesto por ICONA. Para ello se calcularon cuatro estimadores basados en la precipitación mensual en 74 estaciones pluviométricas repartidas por la geografía peninsular. El análisis de regresión llevado a cabo demostró que el índice de Fournier modificado (MFI) es el mejor estimador. La aplicabilidad del modelo global generado inicialmente se evaluó mediante la comparación con resultados obtenidos a nivel regional. Se observó que tres comunidades autónomas del este peninsular (Cataluña, Comunidad Valenciana y Región de Murcia) presentaban un régimen de precipitaciones diferente al resto de la Península, por lo que se efectuó un nuevo análisis de regresión dividiendo el territorio en dos zonas: zona Este y resto de la península. A partir del estudio comparativo de los resultados, se concluyó que el modelo bizonal basado en el índice de Fournier modificado para un intervalo de 10 años permite obtener, de manera sencilla, una estimación lo suficientemente precisa y exacta del factor R en la España peninsular. Finalmente, se determinó que el modelo disponible propuesto por ICONA tiende a sobreestimar el factor R en aproximadamente un 19%

Effect of the hard magnetic inclusion on the macroscopic anisotropy of nanocrystalline magnetic-materials

It is shown that the presence of highly anisotropic magnetic precipitates in a soft multiphased matrix can produce a remarkable hardening, even when the volume fraction of the precipitates is small. The exchange coupling between the matrix and the precipitates is the relevant parameter. In particular, the simplified analysis we develop in this paper accounts for the magnetic hardening observed in very soft Fe-rich nanocrystals after annealing at higher temperatures

On Unitary Time Evolution in Gowdy T3T^3 Cosmologies

A non-perturbative canonical quantization of Gowdy $T^3$ polarized models carried out recently is considered. This approach profits from the equivalence between the symmetry reduced model and 2+1 gravity coupled to a massless real scalar field. The system is partially gauge fixed and a choice of internal time is performed, for which the true degrees of freedom of the model reduce to a massless free scalar field propagating on a 2-dimensional expanding torus. It is shown that the symplectic transformation that determines the classical dynamics cannot be unitarily implemented on the corresponding Hilbert space of quantum states. The implications of this result for both quantization of fields on curved manifolds and physically relevant questions regarding the initial singularity are discussed.Comment: 16 pages, no figures, latex file; references added, a proof included. Final version to appear in IJMP

Interplay between the magnetic anisotropy contributions of Cobalt nanowires

We report on the magnetic properties and the crystallographic structure of the cobalt nanowire arrays as a function of their nanoscale dimensions. X-ray diffraction measurements show the appearance of an in-plane HCP-Co phase for nanowires with 50 nm diameter, suggesting a partial reorientation of the magnetocrystalline anisotropy axis along the membrane plane with increasing pore diameter. No significant changes in the magnetic behavior of the nanowire system are observed with decreasing temperature, indicating that the effective magnetoelastic anisotropy does not play a dominant role in the remagnetization processes of individual nanowires. An enhancement of the total magnetic anisotropy is found at room temperature with a decreasing nanowire diameter-to-length ratio (d/L), a result that is quantitatively analyzed on the basis of a simplified shape anisotropy model.Comment: 8 pages, 4 figure

Obtaining a Maximum AADT Sustained by Two-lane Roads: An Application to the Madrid Region in Spain

AbstractAt the time of developing the latest Road Master Plan for the Madrid Region (Spain), the question came up as to what traffic volume should be established as a criterion to trigger the upgrade of a two-lane highway to a four-lane facility. Conventional wisdom suggested a maximum annual average daily traffic (AADT) of 10,000 veh/day. The main objective of this research was to determine whether 10,000 veh/day is a reasonable upgrade threshold or if this threshold is too conservative and a higher value can be adopted. Assessment was made based on actual traffic volume measured in two-lane facilities, service vehicle tables provided by different highway agencies and a statistical analysis of the traffic volume distribution of in-service facilities in the Madrid Region. A total of 36 segments exceeding an AADT of 10,000 veh/day at some point between 1998 and 2008 were found and analyzed. Results indicated that maximum observed values fit fairly well with the service volume tables provided by HCM 2010 and FDOT and an increase in the upgrade threshold is feasible. These results offer guidance as to what value can be considered for future planning applications, including impact traffic studies and local and regional planning

ARE PEOPLE IN IFUGAO, PHILIPPINES ENTREPRENEURIAL?

A person's target and option depend on different processes of thought. These cycles of thinking and motives either drive or drag the participant to the creative exercises of entrepreneurship. This research explored the entrepreneurial traits, reasons, difficulties, and obstacles faced by Ifugao citizens in the Philippines while doing business. The relationship between the above variables and the entrepreneurial aspirations of Ifugao individuals was also calculated. Data were collected from 263 Ifugao, both beneficiaries and non-beneficiaries of the programs of various government agencies in the province using snowball sampling through a research questionnaire and semi-structured interview.  Using means, the Mann-Whitney U test, and the rank order correlation of Spearman, this paper finds that considering the difficulties and obstacles they face, Ifugao individuals retain the character of becoming an entrepreneur. Overall, five traits that are common to respondents have been identified. Ifugao people stay inspired, and it motivates them to persevere constantly in carrying out entrepreneurial practices. Finally, the findings of this study indicate that training, seminars, and workshops, the positive perceived image of entrepreneurs, and motives have a significant impact on the entrepreneurial purpose of Ifugao people, which is essential for entrepreneurial success. Keywords: Entrepreneurial Characteristics, The Perceived Image on Entrepreneurship, Motivations, Problems and Challenges, Entrepreneurial Intention, Ifugao People, Philippines

Formulación matemática de algunos modelos físicos utilizados en la reconstrucción de un evento de tránsito y las consideraciones para su implementación

Los procedimientos analíticos empleados para inferir magnitudes físicas en los eventos de tránsito (modelos físicos), son siempre construcciones teóricas que permiten abordar el problema. Estos modelos pueden ser mejorados al considerar variables que antes fueron descartadas, teniendo especial cuidado en los límites de aplicabilidad para poder interpretar correctamente los resultados obtenidos.The analytic procedure used to infer physical cuantitires in traffic events (physical models), are theoretical basis that allows solving the problem. This models can be improved using previous discarded variables, taking special care of aplicatibility bounds in order to achieve best result interpretation