On Friday, 3 March 2017, at about 18:19 h, a metro track failed, prompting about 50% of Mexico City's metro line-C to a halt. The track failure occurred at a peak hour when tens of thousands of commuters were heading to their homes. Given the interdependency among the modes of transportation in the capital city, the incident caused heavy disruption; it is believed that about 45,000 commuters were affected. A systemic safety management system ('SSMS') model has been used for the analysis. The results showed that: a) the model demonstrated its potential to the analysis of the transport system interdependency; it has been found that failure propagates vertically and horizontally; b) the model highlighted that failure propagation has to do with a coordination function; c) in relation to the case study, it has been found that the actions taken by the decision-makers during the emergency were less than adequate; d) the commuters traveling patterns should be considered when designing emergency plans; and, e) more generally, there is a need for the creation of a system to manage critical infrastructure protection in the context of Mexico. It is hoped that by conducting such analyses, we may gain a better understanding of the complexity of cities.

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This paper presents some of the results of a cross-sectional study conducted in Mexico City in 2015-2016. The approach has been the application of a questionnaire to a sample size of n = 1489. Six high schools participated in the study that are located within the seismic zones of the city. Some of the results and conclusions are given below: (a) 95% of the students have experienced an earthquake and 71% considered that earthquakes cannot be predicted; however, 29% did not know this fact; (b) 82.2% of students were all aware of the likelihood of an earthquake occurrence sometime in the future. (c) One of the key conclusions is associated with the need to educate the residents of the capital city on a more realistic scale of the size of an earthquake; this could be the "Modified Mercalli Intensity Scale" or similar. (d) More generally, the residents of the city should be educated with urgency on these basic concepts. The more effective is the communication on risks and consequences, the better may be their preparedness to earthquakes.

Although GPUs can offer higher computing power at low power consumption, their low-level programming can be relatively complex and consume programming time. For this reason, directive-based alternatives such as OpenACC could be used to specify high-level parallelism without original code modification, giving very accurate results. Nevertheless, in the FDTD method, absorbing boundary conditions are commonly used. The key to successful performance is correctly implementing the boundary conditions that play an essential role in memory use. This work accelerates the simulations of electromagnetic wave propagation that solve the Maxwell curl equations by FDTD using CMPL boundary in TE mode using OpenACC directives. A gain of acceleration optimizing the use of memory is shows, checking the loops intensities, and the use of single precision to improve the performance is also analyzed, producing an acceleration of around 5X for double precision and 11X for single precision respectively, comparing with the serial vectorized version, without introducing errors in long-term simulations. The scenarios of simulation established are common of interest and are solved at different frequencies supported by a Mid-range cards GeForce RTX 3060 and Titan RTX.