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Accessibility is now a common way to measure the benefits provided by transportation–land use systems. Despite its widespread use, few measurement options allow for the comparison of accessibility across multiple urban systems, and most do not adequately control for market competition between demand-side actors and supply-side facilities in localized markets. In this article, we develop a measure of competitive access to destinations that can be used to accurately compare accessibility between regions. This measure stems from spatial interaction modeling and accounts for competition at both the supply and demand sides of analysis, regional differences in transportation networks and travel behavior, and any imbalance between the size of the population and the number of opportunities. We use this method to compute access to employment for Canada's eight largest cities to comparatively examine inequalities in accessibility, both within and between cities, and by travel mode.  相似文献   
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Communities living on remote islands are often viewed as among the most exposed and vulnerable to climate change impacts. This study uses the Sustainable Livelihoods Framework to investigate how indigenous communities living on two physically different islands in Torres Strait, Australia, experience what they consider to be the impacts of climate change in relation to their daily lives. During this process, a series of natural, physical, and socio‐cultural limits and barriers to climate change adaptation were identified on Boigu, a low‐lying mud island inundated by the sea during high tides and storm surges. As a volcanic island, Erub's elevation is higher but significant community infrastructure, housing, and cultural sites are located on the low coastal fringe. No immediate limits to climate change adaptation were identified on Erub, but physical and socio‐cultural barriers were revealed. Limits to climate change adaptation occur when adaptation actions fail to protect the things valued by those affected, or few adaptation options are available. Barriers to climate change adaptation may be overcome if recognised and addressed but can become entrenched limits if they are ignored. Within the participating communities, such limits and barriers included (a) restricted adaptation options due to limited access to particular livelihood assets; (b) difficulty engaging with government processes to secure external support; and (c) people's place‐based values, which evoke a reluctance to relocate or retreat.  相似文献   
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This paper investigates the applicability and transferability of conventional frameworks of archaeological survey in the context of marginal alluvial environments, particularly the unique inland deltas of Central Asia. These dynamic and visually obstructed landscapes pose unique challenges not only to survey methodologies but also to theory and interpretation. Here, an exploratory approach to data analysis is used that applies three distinct yet integrated methodologies: visibility analysis, multi-scalar spatial analysis and directional (anisotropic) statistics. This approach thereby moves beyond many of the existing conceptual constraints about how we understand surface distributions in arid alluvial landscapes and ultimately identifies both transferable analytical methods and new fieldwork agendas that are relevant to a wide range of survey projects.  相似文献   
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The Ramat Saharonim site, located in the central Negev desert, Israel, consists of four shrines in a shallow valley and 30 tumuli, aligned on two cuesta cliffs on the valley's sides. Previous assessments based on site surveys suggested a general chronological span from Late Neolithic period (ca. 5000–5500 BC) through the Early Bronze Age (third millennium BC). Excavations in one shrine and three tumuli revealed a well-constructed double wall at the shrine and seven primary adult burials in the three tumuli. Quartz from sediment samples post-dating the construction of the burials and shrine was dated by optically stimulated luminescence (OSL) using the single aliquot regenerative dose (SAR) protocol, and charcoal and leather samples were dated by 14C. The OSL results for a burial in one tumulus are 7500 ± 700 to 6000 ± 600 years. In a second tumulus, OSL ages of 2000 ± 200–1800 ± 170 years and a 14C age on leather of 390–200 BC (2340–2150 cal BP) imply that this burial is Nabatean and that the site was used also in the Hellenistic period. Two 14C ages on charcoal from the shrine give an age between 5280 and 4710 BC (7230–6660 cal BP). OSL single aliquot ages for sediment from the shrine are highly scattered and far too old (60,000 to 12,000 years). The unlikely old ages are due to insufficient resetting of the OSL signal of some of the quartz grains when sand was blown onto the site. Indeed, single grain measurements for six samples of sediment postdating the shrine show a very large range of grain ages, but with a distinct young population in all samples. Ages calculated from these young populations average 5400 ± 800, in better consistence with the 14C dates and confirming our supposition that only some of the transported grains were reset at the time of deposition. The combined OSL and 14C dating shows that the shrines and tumuli are contemporaneous and attributes the complex to the Late Neolithic. This has clear ramifications for our understanding of the period and the rise of desert pastoral societies.  相似文献   
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This paper assumes that there is something in the logic of the capitalist mode of production such that, in the words of Marx and Engels' Communist Manifesto, it “must nestle everywhere, settle everywhere, establish connections everywhere,” giving a “cosmopolitan character to production and consumption in every country.” It assumes, that is, that there is an inherent tendency in capitalism to seek to globalize. Further, it is argued that one can plausibly claim that the capitalist mode of production has succeeded, or is succeeding, in globalizing against the countervailing forces of the managing state and organized labor. It is argued that this development represents, to use Marcuse's words, something like a “closing of the universe of discourse” or a “paralysis of criticism” and the emergence of a “society without opposition,” but in a context, in crucial respects, fundamentally different from that analysed by Marcuse in the 1960s.  相似文献   
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