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Metropolitan strategic plans often focus on strengthening local employment opportunities to address the congestion and commuting issues threatening city sustainability. The success of such strategies relies on a more equitable distribution of jobs between sub-regions and can be comparatively benchmarked through one of the three related measures of employment self-sufficiency, self-containment or jobs-housing balance. However, in practice, planning policy implementation to meet these targets seldom reduces automobile commuting. This paper investigates self-containment across a range of occupation and industry types to highlight large differences in commuting and employment patterns through a case study of Perth’s Northwest sub-region, Western Australia. Its findings suggest the application of current sub-regional policy and targets within Perth may reinforce the wage and skill disadvantage of outer metropolitan sub-regions over the inner core. It recommends a more nuanced understanding of these measures taking into account the complex dynamics of both employment opportunities and commuting patterns across sub-regions of a city. 相似文献
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Computational Visual Media - Traffic sign detection is one of the key components in autonomous driving. Advanced autonomous vehicles armed with high quality sensors capture high definition images... 相似文献
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Acta Informatica - Program synthesis is the problem of computing from a specification a program that implements it. New and popular variations on the synthesis problem accept specifications in... 相似文献
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Experimental study of early-age behavior of high performance concrete deck slabs under different curing methods 总被引:3,自引:0,他引:3
Curing techniques and curing duration have crucial effects to the strength and durability of concrete. Proper curing can protect against moisture loss from fresh concrete. The objective of this experimental study is to examine the early-age behavior of high-performance concrete (HPC) under various curing methods. Laboratory experiments were conducted to investigate the early-age shrinkage development, temperature change, and evaporation rate when different curing methods were used. Four curing techniques and two curing durations were applied to concrete deck slab and cylindrical specimens. The measured experiment data were also compared with several shrinkage prediction models. The results show that proper moisture-curing methods can effectively reduce concrete temperature due to hydration heat and limit the development of early-age shrinkage strains. The concrete of a longer curing duration would yield lower shrinkage deformation and lower evaporation rate. 相似文献
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Low-temperature, or psychrophilic (<20 degrees C) anaerobic digestion has been proven feasible for the mineralisation of simple wastewaters. In this study, hybrid expanded granular sludge bed-anaerobic filter (EGSB-AF) bioreactors were used to evaluate the feasibility of psychrophilic digestion for the treatment of phenol-containing wastewater. Efficient chemical oxygen demand and phenol removal were observed at organic and phenol loading rates of 5 kg COD m(-3)d(-1) and 0.4-1.2 kg phenol m(-3)d(-1) (400-1200 mg phenol [l wastewater](-1)), respectively. There was no long-term accumulation of volatile fatty acids in the reactor systems. Methanogenic activity was developed under psychrophilic conditions but anaerobic methane-producing populations remained mesophilic throughout the trial of 415 days. 相似文献
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Fifty-eight brands of balsamic vinegars were analyzed for lead concentrations and isotopic compositions (204Pb, 206Pb, 207Pb, and 208Pb) to test the findings of a previous study indicating relatively high levels of lead contamination in some of those vinegars — more than two thirds (70%) of them exceeded California's State Maximum Level (34 μg/L) based on consumption rates ≥ 0.5 μg Pb per day. The Lead isotopic fingerprints of all those vinegars with high lead concentrations were then found to be primarily anthropogenic. This isotopic analysis unquestionably reveals multiple contamination sources including atmospheric pollutant Pb and an unidentified contamination source, likely occurring after grape harvest. Organically grown grape vinegars display the same Pb content and isotopic signatures as other vinegars. This implies that pesticides might not be a significant source of pollutant Pb in vinegars. A significant post-harvest contamination would be inherited from chemicals added during production and/or material used during transport, processing or storage of these vinegars. This is consistent with the highest Pb levels being found in aged vinegars (112 ± 112 μg/L) in contrast to other vinegars (41.6 ± 28.9 μg/L) suggesting contamination during storage. It is, therefore, projected that lead levels in most vinegars, especially aged balsamic and wine vinegars, will decrease with improvements in their manufacture and storage processes consequential to recent concerns of elevated levels of lead in some vinegars. 相似文献