Aya Saito

Public acceptance of CO2 capture and storage technology: A survey of public opinion to explore influential factors

Publisher Summary CO2 capture and storage (CCS) technology is an emerging technology with large potential for CO2 emission mitigation. However, public acceptance is an unknown factor in developing public policy involving CCS technology. Characteristics of this technology substantially differ from other options for CO2 mitigation, particularly when assessing the risks of leakage and development of appropriate regulatory penalties in implementing some form of CCS. A comprehensive CO2 mitigation policy portfolio that includes CCS requires sufficient public outreach for assuring its political feasibility. In order to effectively design public outreach programs, it is useful to begin by assessing current potential acceptability of public on CCS and also to identify factors influencing public acceptance of this technology. Although a preliminary qualitative analysis on this matter based on focus group approach in U.K. is available, there has been little statistically based research on the matter in Japan and in other countries until now. The objective of this chapter is to provide such information.

Investigation of optimum anti-scatter grid selection for digital radiography: physical imaging properties and detectability of low-contrast signals

Our aim in this study was to evaluate the effect of the grid variations on the imaging performance for a computed radiographic system under identical exposure condition. Digital radiographies using a 20-cm Lucite phantom were performed without grid and with grid ratios of 5:1, 8:1, 10:1, 12:1, and 14:1. The scatter fraction, the incident dose to the image receptor, the Wiener spectrum (WS), and the noise-equivalent quanta (NEQ) were measured. Visibility of low-contrast signals was evaluated using a contrast-detail phantom. The scatter fractions decreased considerably with an increase in the grid ratio. On the other hand, the WSs were increased (the noise property deteriorated) as the grid ratio increased due to a decreased incident dose to the image receptor under the identical exposure condition. The NEQs were improved as the grid ratio increased. The high grid ratios provided higher low-contrast detectability compared to the low grid ratios. Our results indicated that the removal of scattered radiation was very effective in improvement of the NEQ in the digital system under the identical exposure condition.