Tracing Issue Definition and Policy Change: An Analysis of Disability Issue Images and Policy Response

We examine the role of issue definition in disability policy change. Based on qualitative and quantitative evidence from media coverage and congressional hearings, we conclude that policy change was influenced by the redefinition of disability issues from medical and economic definitions to a new sociopolitical perspective. Specifically, we find evidence that media attention and tone influenced the number of congressional hearings and the tone of these hearings. The change in the congressional definition subsequently contributed to the passage of key legislation based on the sociopolitical/civil rights definition of disability. Importantly, our research supports previous studies that suggest problem definition helps to explain significant policy change.     

Mössbauer Spectroscopic and Chromaticity Analysis on the Colourative Mechanism of Ancient Goryeo Celadon from GangJin and Buan

In ancient Goryeo celadon excavated from the kiln sites in the GangJin and Buan areas, the effect of the chemical composition and ionic state of Fe on the colour was evaluated by Mössbauer spectroscopy and chromaticity analysis. According to chromaticity analysis, the L* value (brightness) of the glaze was shown to be affected more by TiO₂ and MnO than by Fe₂O₃, and the body was affected more by Fe₂O₃ than by TiO₂. The a* value was found to be affected by Fe₂O₃ and TiO₂ in the glaze, whereas there was hardly any change in the body according to the composition. As for the b* value, changes due to the composition were shown to be smaller than those for the L* and a* values. According to the Mössbauer spectroscopy results, as the quantities of TiO₂ and Fe₂O₃ are increased, Fe²⁺/Fe³⁺ decreases; while the changes in Fe²⁺/Fe³⁺ with MnO and P₂O₅ are negligible. As the quantity of Fe²⁺/Fe³⁺ increases, the a* and b* values decrease, which results in the change of colour from red–yellow to blue–green. The characteristic green colour can be attributed to increased L* (brightness) and decreased a* and b* values (blue–green shift) due to the reduced Fe ion, which is mainly determined by the TiO₂ and Fe₂O₃ contents.     

Parameterized Seismic Fragility Curves for Curved Multi-frame Concrete Box-Girder Bridges Using Bayesian Parameter Estimation

This paper addresses the application of a Bayesian parameter estimation method to a regional seismic risk assessment of curved concrete bridges. For this purpose, numerical models of case-study bridges are simulated to generate multiparameter demand models of components, consisting of various uncertainty parameters and an intensity measure (IM). The demand models are constructed using a Bayesian parameter estimation method and combined with limit states to derive the parameterized fragility curves. These fragility curves are used to develop bridge-specific and bridge-class fragility curves. Moreover, a stepwise removal process in the Bayesian parameter estimation is performed to identify significant parameters affecting component demands.     

VEHICLE ACCESS AND EXPOSURE TO NEIGHBORHOOD POVERTY: EVIDENCE FROM THE MOVING TO OPPORTUNITY PROGRAM

The geographic determinants of social and economic opportunity have received much scholarly attention. A missing link in this body of research is an emphasis on the range of factors influencing low‐income households’ exposure to neighborhood poverty over time. This paper examines the dynamics of exposure to neighborhood poverty for Moving to Opportunity (MTO) program participants. Our paper is unique in its emphasis on the role of vehicle access as it shapes exposure to neighborhood poverty. We find that vehicle access is an important factor shaping residential spells and transitions to low‐poverty neighborhoods over time. We also find that the combined influence of a geographically‐targeted residential mobility requirement and vehicle access substantially elevates a household's likelihood of accessing and staying in a low‐poverty neighborhood. These findings suggest that residential mobility programs and similar efforts to spatially deconcentrate poverty should pay particular attention to the transportation needs of low‐income households.