No abstract

No abstract

Abstract:The ultimate goal of urban water infrastructure asset management may be sustainable water supply with satisfaction for customers. In this work, we attempted to evaluate the gaps between the perspectives of customers and service providers in Korea's water infrastructure asset management. To evaluate the customers' perspective, a hierarchical questionnaire survey was conducted to estimate the weights of influence for six customer values and their attributes on Korean water utility management. To evaluate the service providers' perspective, an AHP (Analytic Hierarchy Process) analysis was performed to estimate the weights of influence for the customer values and their PIs (performance indicators). The gap analysis results show that customers place higher value on customer service satisfaction (emotion and information) than do the service providers (managers), whereas the managers place more value on affordability than do the customers. The findings from this work imply that improving customer service is effective in satisfying the desirable water LOS (level of service) for customers. Recommendations have also been provided for administrators and engineers to develop integrated decision-making systems OPEN ACCESSSustainability 2015, 7 13335 that can reflect customer needs regarding the improvement of their water infrastructure asset management. The findings from this work may be helpful for the Korean government and water supply utilities in improving the sustainability of their water infrastructure asset management.

A B S T R A C TFat, oil, and grease (FOG) is the most common factor in sewer pipe blockage, and is the source of inundation and sanitary sewer overflows (SSOs). In the US and the UK, many inundation or SSO events occur each year, and a great deal of cost has been incurred to improve these situations. However in Korea, the database for sewer maintenance is still insufficient. In this study, FOG deposits collected in Korea were analyzed, and the characteristics of the FOG deposits were compared with the characteristics of the FOG deposits from places with different food cultures investigated in some of the major previous studies. Six FOG samples were collected from sewer mains and service laterals in the sewerage systems. The characteristics of the six samples were examined using FT-IR, Ca ion, and fatty acid composition analyses. The results of the FT-IR analysis indicated that the spectra defined in the previous studies of FOG were observed, and thus similarity to the samples of the previous studies was found. The proportions of the Ca ions included in the FOG of the six samples were 0.02-0.59%, and they are thought to be related with the maintenance of the discharging sources where the samples were collected. The results of the fatty acid composition analysis indicated that the proportions of total fat in the FOG ranged from 6 to 33%, and the proportion of total fat in the FOG decreased as the proportion of saturated fatty acid in the total fat increased. In some of the major studies performed previously in the US and the UK, saturated fatty acids accounted for a high proportion of the fatty acid compositions. However, the six FOG deposits analyzed in this study showed different compositions. It is thought that the fatty acid composition of FOG could vary with differences in the food culture, and the characteristics of FOG deposits could also vary. The data obtained from this study and future studies would be useful for the effective management of FOG deposits that are formed based on the food culture.