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Household resilience to natural hazards is a critical issue facing society with the advent of climate change. In this work, we developed one of the first household natural hazard resilience geospatial models for Rwanda designed to understand household resilience at detailed spatial resolutions. We evaluated indicators within the model through empirical fieldwork using an easy-to-deploy survey on Android tablets. To the best of our knowledge, the work presented here is innovative as it is some of the first to use geospatial technology-based surveys to conduct household-level natural disaster resilience surveys in Rwanda. Select results presented in this paper indicated that household vulnerabilities and subsequent resilience generally matched existing district-level risk mapping of Rwanda. However, our work went beyond existing risk mapping to understand individual household perceptions of resilience. Respondents generally reported a mix of positive and negative drivers of household resilience. Security vis-à-vis natural disasters and economic situation was perceived as very insecure, healthcare and education were very secure, and utilities, food and water, and housing were generally perceived as insecure but not as insecure as economic situation and security to future disasters. There is much more that can be understood in terms of household resilience as it relates to many factors of household resiliency in our model including physical vulnerabilities, financial capacity, information access, technological capacity, and most importantly, resilience perceptions. 

Nonsolvent induced phase separation (NIPS) is a widely occuring process used in industrial membrane production, nanotechnology and Nature to produce microstructured polymer materials. A variety of process-dependent morphologies are produced when a polymer solution is exposed to a nonsolvent that, following a period where mass is exchanged, precipitates and solidifies the polymer. Despite years of investigation, both experimental and theoretical, many questions surround the pathways to the microstructures that NIPS can produce. Here, we provide simulation results from a model that simultaneously captures both the processess of solvent/nonsolvent exchange and phase separation. We show that the time it takes the nonsolvent to diffuse to the bottom of the film is an important timescale, and that phase separation is possible at times both much smaller and much larger than this scale. Our results include both one-dimensional simulations of the mass transfer kinetics and two- and three-dimensional simulations of morphologies at both short and long times. We find good qualitative agreement with experimental heuristics, but we conclude that an additional model for the vitrification process will be key for fully explaining experimental observations of microstructure formation.