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This paper presents the application of the Weather Research and Forecasting (WRF version 3.5) with high spatial resolution (3 and 1 km) testing four Planet Boundary Layer (PBL) schemes to the complex topography of Mexico in different numerical experiments that have tried to find the best configuration. The WRF is a Numerical Weather Prediction (NWP) model giving support for weather forecasting and modeling in Chemical Transport (CTM) or Air Quality Models as CMAQ or CHIMERE. For the above, the objectives in this work were assess the performance, the best grid parameterization, meteorological initial conditions, temporal resolution, time step and PBL schemes used in order to minimize the execution time and to show changes in speedup and efficiency. Mare Nostrum III supercomputer was used for the computational processing in the cluster. The computational performance indicators were execution time, speedup and efficiency. The sensitivity analysis was performed using the mean bias (MB) and root mean square error (RMSE) from variables obtained by WRFv3.5 such as temperature, windspeed, sea level pressure and the METAR Veracruz airport station observations. The results show that Mellor-Yamada-Janjic (MYJ) scheme was better in computational parallel execution with at least 8 processors and a time step of 18 seconds. The sensitivity analyses show that time step is not a key in the accuracy of the meteorological values obtained. It is necessary consider the lack of data in METAR stations in Mexico.

Mexico and currently in Veracruz state, there are metropolitan zones (MZ) growing. Therefore, main objective in this paper is to analyze new data and AQ trends during 01.09.2013 to 30.06.2015 of two new AQ monitoring stations installed in Xalapa and Minatitlan MZ in 2013-year. The methodology applied used quality criteria to the datasets, followed by data validation and statistics for further analysis to determine the hourly, weekly and yearly trends of NO 2 , O 3 , SO 2 , PM 10 and PM 2.5. Indicators were compared with Mexican standards, CAI-LAC report, WHO guidelines, EU and USA standards to evaluate the AQ in both sites. We observed AQ trends from moderate to bad in Xalapa and Minatitlan MZ where the PM 10 and PM 2.5 surpassed the WHO guidelines and Mexican standards. O 3 and SO 2 in Xalapa presented a quality from good to moderate and in Minatitlan sometimes were from moderate to bad. NO 2 did not exceed the value limits of Mexican standards, only Xalapa has exceeded the WHO guidelines. In Minatitlan, the Mexican limits were not exceeded. Concluding, PM 10 and PM 2.5 concentrations were the main problem. Others pollutants that influenced the AQ were O 3 , NO 2 and SO 2 in Minatitlan MZ due probably to meteorology, site conditions, location and oil and petrochemical industries. In Xalapa, MZ NO 2 and SO 2 are attributed mainly to road transport.

El adecuado modelado de los apoyos y cargas que actúan sobre una viga, es esencial para contribuir al apropiado comportamiento físico de la viga durante su vida. En este artículo se describe una aplicación creada en Matlab y diseñada con la finalidad de contribuir al aprendizaje de los estudiantes (principalmente de ingeniería civil y de arquitectura), en el tema del comportamiento físico y del modelado de las vigas estáticamente determinadas. Particularmente, el énfasisse centra en dos grandes aspectos: a) el comportamiento físico de las vigas y; b) la relación entre la pendiente, la deflexión, la fuerza cortante y el momento flexionante en vigas. La ayuda computacional mencionada permite calcular los valores de fuerza cortante, momento flexionante, pendiente y la deflexión en una viga. Para ese fin es necesario definir los tipos de apoyos de la viga en sus extremos, y el tipo de carga que actúa sobre ella. Los resultados generados por la aplicación se muestran gráficamente y en forma numérica. La aplicación descrita en el presente trabajo permite analizar una viga estáticamente determinada, y puede ejecutarse en cualquier computadora con un sistema operativo Windows 7 ó superior de 64 bits, sin necesidad de tener instalado el software Matlab. Finalmente, se describen ejemplos de uso de la aplicación.