Investigating Private Motorised Travel and Vehicle Fleet Efficiency: Using New Data and Methods to Reveal Socio‐Spatial Patterns in Brisbane,Australia

Australian cities have seen continued long‐term growth in private motor vehicle travel that has imposed increasing vehicle energy consumption and greenhouse gas emissions. This paper investigates the spatial patterns of vehicle energy consumption on urban areas through an analysis of vehicle travel and of vehicle fleet efficiency in Brisbane, Australia. This is achieved by combining motor vehicle registration records and Australian government's ‘Green Vehicle Guide’ of vehicle fuel efficiency database. The results of a spatial analysis of the private vehicle trip distances derived from journey to work data and fuel energy consumption associated with the private‐owned vehicles decomposed to local areas show that private vehicle energy use tends to increase with increasing distance from the city centre (e.g. central business district). This analysis demonstrates that differences in vehicle trip distances and lower proportions of high‐efficiency vehicles in the outer suburbs aggravate vehicle energy consumption in those locations. The paper further compares vehicle energy use results for Brisbane against spatial patterns of suburban socio‐economic disadvantage. The paper demonstrates that access to vehicle fleet technology may compound other forms of socio‐economic disadvantage and vulnerability.     

明代盐法之演变与盐商之变化

明代的盐法是从宋元时期的盐法继承而来的,在国家专卖制度下组织了灶户制度,随着明初钞法的破坏,以及社会经济的变化,明代的盐法经历了一系列深刻的变化,如允许余盐和正盐一样可以公开进入国家的专卖体系;明中叶以后又出现了纳银开中制度等。所有的这些变化并不仅仅是盐法自身的变化,它也引起了与明代盐法变化密切相关的商人的地位与命运的变化。     

The geochemical evolution of very dilute CO2‐rich water in Chungcheong Province,Korea: processes and pathways

A geochemical study was carried out on the CO₂‐rich water occurring in granite areas of Chungcheong Province, Korea. In this area, very dilute and acidic CO₂‐rich waters [62–242 mg l^?1 in total dissolved solid (TDS), 4.0–5.3 in pH; group I) occur together with normal CO₂‐rich waters (317–988 mg l^?1 in TDS, 5.5–6.0 in pH; group II). The concentration levels and ages of group I water are similar to those of recently recharged and low‐mineralized groundwater (group III). Calculation of reaction pathways suggests that group I waters are produced by direct influx of CO₂ gas into group III type waters. When the groundwater is injected with CO₂, it develops the capacity to accept dissolved solids and it can evolve into water with very high solute concentrations. Whether the water is open or closed to the CO₂ gases becomes less important in controlling the reaction pathway of the CO₂‐rich groundwater when the initial pco ₂ is high. Our data show that most of the solutes are dissolved in the CO₂‐rich groundwater at pH > 5 where the weathering rates of silicates are very slow or independent of pH. Thus, groundwater age is likely more important in developing high solute concentrations in the CO₂‐rich groundwaters than accelerated weathering kinetics because of acidic pH caused by high pco ₂.     

Rural Youth Migration Trends in Australia: an Overview of Recent Trends and Two Inland Case Studies

Much of what has been written on the topic of Australian rural youth migration trends and processes has often proceeded from data‐free, or data‐poor grounds. In this context, this paper analyses recent trends in youth (15 to 24 years of age) migration for a temporally‐consistent set of Statistical Divisions (SDs) in inland rural Australia, and for local government areas within the Northern Tablelands and Slopes and Ranges of northern New South Wales and the Western Australian Central Wheatbelt. The paper finds that rates of youth loss from rural regions have increased over the past twenty years. Yet the patterns, processes, causes and impacts of rural youth migration are distributed in a spatially‐uneven fashion. Some remote areas are receiving net migration gains while booming ‘sea change’ coastal regions have experienced heavy losses. While the ‘flight to the bright city lights’ syndrome is evident, relatively high proportions of young people in the Northern SD of NSW move within their immediate region. Nevertheless, some common understandings concerning youth mobility were also confirmed. Gender differentials in migration propensity between women and men are evident even at quite local scales. Young people are also more likely to search out capital cities than the rest of the population. Most inland areas still continue to experience heavy losses of local youth. A more precise understanding of rural youth migration trends is an important stepping stone in the establishment of a reinvigorated research effort into young rural people's perspectives of their changing life chances in their home communities.     

EVALUATION OF CAPACITY SPECTRUM METHOD FOR ESTIMATING THE PEAK INELASTIC RESPONSES

The accuracy of the capacity spectrum method (CSM) depends on the precise estimation of equivalent period and damping ratio as well as the modification of the demand spectrum. In this paper, the CSM provided in ATC-40 for estimating the peak inelastic responses is evaluated. First, the effect of equivalent period and damping ratio estimation on the accuracy of the CSM is assessed. Analyses results indicate that the difference between estimation methods is large when the structural nonlinearity is large, but becomes negligible as the hardening ratio increases. Next, the reduction factors provided in ATC-40 and Eurocode are evaluated. It is found that the acceleration responses obtained using the factor of Eurocode is closer to the actual ones than those obtained using the factors of ATC-40. Finally, the demand spectrum is constructed using the peak absolute acceleration and pseudo-acceleration. The results obtained using the peak absolute acceleration is found to be generally larger than those obtained using the pseudo-ones. Since the original CSM generally underestimates the response, the use of peak absolute acceleration in the construction of demand spectrum produces the response relatively closer to the exact one. However, the use of peak absolute acceleration overestimates the response more when the original CSM overestimates the response.