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Scientific research proposing any type of device/technique for seismic protection of buildings is generally based on numerical models that adopt simplifica

Forty years of China's reform and opening-up has fueled large-scale migration, which produced a huge floating population of children who switch between the state of being 'left-behind' and being 'migrant'. They have now grown up to become a new generation of domestic migrants in Chinese cities, facing difficulties in attending school and high dropout rate due to household registration system, reduced social mobility, and alienation from cultural traditions. Data analysis and social surveys show that their all-round development have been hindered by multiple factors, such as unequal distribution of educational resources, restricted migration, unbalanced distribution of social dividends, little social mobility, and the rupture of the traditional rural education system. Although this phenomenon has long been studied by the academic community, most of the previous works placed emphasis on analyzing survey data and describing the general trends, while little attention has been paid to synthesizing the underlying causes and the insidious consequences. The focus of this paper is to explore how the development of left-behind and migrant children is conditioned by multiple factors such as social structures, institutional arrangements, intergenerational changes, cultural shifts and educational systems. Building on the latest official data and literature, this work is empirically based on years of social observation, case study, and in-depth interviews. The aim is to identify the shortcomings in the education and policy system, while furthering the current understanding of the gains and losses of individuals, families and the nation in the process of China's rapid rise.

In light of the significant damage observed after earthquakes in Japan and New Zealand, enhanced performing seismic force‐resisting systems and energy dissipation devices are increasingly being utilized in buildings. Numerical models are needed to estimate the seismic response of these systems for seismic design or assessment. While there have been studies on modeling uncertainty, selecting the model features most important to response can remain ambiguous, especially if the structure employs less well‐established lateral force‐resisting systems and components. Herein, a global sensitivity analysis was used to address modeling uncertainty in specimens with elastic spines and force‐limiting connections (FLCs) physically tested at full‐scale at the E‐Defense shake table in Japan. Modeling uncertainty was addressed for both model class and model parameter uncertainty by varying primary models to develop several secondary models according to pre‐established uncertainty groups. Numerical estimates of peak story drift ratio and floor acceleration were compared to the results from the experimental testing program using confidence intervals and root‐mean‐square error. Metrics such as the coefficient of variation, variance, linear Pearson correlation coefficient, and Sobol index were used to gain intuition about each model feature's contribution to the dispersion in estimates of the engineering demands. Peak floor acceleration was found to be more sensitive to modeling uncertainty compared to story drift ratio. Assumptions for the spine‐to‐frame connection significantly impacted estimates of peak floor accelerations, which could influence future design methods for spines and FLC in enhanced lateral‐force resisting systems.