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431.
This paper investigates the emergence of a Learning Legacy Agenda (LLA) in the wake of the London 2012 Olympic Games as a governmental tool for the dissemination of urban development and infrastructure project delivery best practice. Focusing on the inception, coordination and implementation of the LLA we outline the intentionalities of mobility that underpin its formation and appropriation and suggest how this points to the emergence of a new “London model” of development and governance. Three intentionalities of knowledge capture, public duty and extra-local salience are unpacked to demonstrate the range of ways in which the bureaucratically initiated LLA banner has been used by various development actors and organisations to validate their existing practices. The case study of the LLA as an institutionalised governance apparatus is used to analyse the impact of specific forms of social relations on the ways in which “models” are produced, what their content consists of, how dominant agendas and narratives co-evolve with the priorities of an assemblage of actors and the processes of selective abstraction used to curate particular messages and forms of fixed and potentially mobile knowledge, yet dubious claims of “learning”. 相似文献
432.
Everyday urban practices are enabled by both formal and informal rights regimes. Researchers often focus on the effects of formal rights; informal rights to use urban spaces have been less widely examined, particularly in North America. This article examines practices of intra-urban mobility in a gentrifying area of Portland, Oregon. We find that rights regimes regarding movement in urban space importantly shape who uses particular transit strategies and infrastructures. Specifically, we identify rights regimes rooted in explications of a city ideal and a neighborhood ethic. We suggest that Portland’s widely admired transit planning process has not sufficiently engaged with informal use rights in transit spaces, leading to uneven adoption of a transportation infrastructure that re-inscribes historic racialized injustices. An examination of informal use rights complicates common rights analytics, including those leveraging Lefebvre’s right to the city, emphasizing how all urban rights are contingent, contested and negotiated. 相似文献
433.
Thorsten Beitter Thomas Wagner Gregor Markl 《Contributions to Mineralogy and Petrology》2008,156(6):689-707
In this study, we have investigated the formation of quartz–kyanite veins of the Alpe Sponda, Central Alps, Switzerland. We
have integrated field observations, fluid inclusion and stable isotope data and combined this with numerical geochemical modeling
to constrain the chemical processes of aluminum transport and deposition. The estimated P–T conditions of the quartz–kyanite
veins, based on conventional geothermometry (garnet–biotite, white mica solvus and quartz–kyanite oxygen isotope thermometry)
and fluid inclusion data, are 550 ± 30°C at 5.0 ± 0.5 kbar. Geochemical modeling involved construction of aqueous species
predominance diagrams, calculation of kyanite and quartz solubility, and reaction–path simulations. The results of the modeling
demonstrate that (1) for the given chemical composition of the vein-forming fluids mixed Al–Si aqueous species are dominant
in transporting Al, and that (2) fluid cooling along a small temperature gradient coupled with a pH decrease is able to explain
the precipitation of the quartz–kyanite assemblages in the proportions that are observed in the Alpe Sponda veins. We conclude
that sufficient amounts of Al can be transported in typical medium- to high-grade regional metamorphic fluids and that immobile
behavior of Al is not very likely in advection–dominanted fluid–rock systems in the upper and middle crust. 相似文献
434.
Kwan-Nang Pang Chusi Li Mei-Fu Zhou Edward M. Ripley 《Contributions to Mineralogy and Petrology》2008,156(3):307-321
Abundant Fe–Ti oxide inclusions in cumulus olivine (Fo77–81) from the Panzhihua and Hongge intrusions, Emeishan large igneous province, SW China, document the first evidence for early
crystallization of Fe–Ti oxides in ferrobasaltic systems in nature. The intrusions also contain significant stratiform Fe–Ti–V
oxide ores. The oxide inclusions are sub-rounded or irregular, range from ∼5 to 50 μm in diameter, and are dominated by either
titanomagnetite or ilmenite. The fact that the inclusions are either titanomagnetite- or ilmenite-dominant suggests that they
are trapped crystals, instead of immiscible oxide melt, formed during growth of the host olivine. The absence of other silicate
phases in the inclusion-bearing olivine is difficult to reconcile with a possible xenocrystic origin of the oxide inclusions.
These oxide inclusions are thus interpreted to be cumulus minerals crystallized together and trapped in olivine from the same
parental magma. In addition to Fe–Ti oxides, some inclusions contain amphibole + biotite ± fluorapatite that might have formed
by reaction of trapped hydrous liquid with the host olivine. Numerical modeling of high-Ti Emeishan basalts using the MELTS
program successfully simulates early crystallization of olivine (∼Fo81) and Fe–Ti spinel in the presence of a moderate amount of H2O (∼1.5 wt%) under pressure and fO2 conditions generally pertinent to the Panzhihua and Hongge intrusions. The modal mineralogy of the oxide inclusions is in
good agreement with the bulk compositions of the ore, as inferred from whole-rock data, in a given intrusion. This is consistent
with the interpretation that the stratiform oxide ores in the intrusions formed by accumulation of Fe–Ti oxide crystals that
appeared on the liquidus with olivine and clinopyroxene. 相似文献
435.
This paper presents a novel framework to analyze pedestrians' behavioral patterns throughout shopping environments in the historical center of Barcelona, Spain. We employ a Bluetooth detection technique to capture a large-scale dataset of pedestrians' behavior over a one-month period, including during a key sales period. We focused on comparing particular behaviors before, during, and after the discount sales by analyzing this large-scale dataset, which is different but complementary to the conventionally used small-scale samples. Our results uncover pedestrians actively exploring a wider area of the district during a discount period compared to weekdays, giving rise to strong underlying mobility patterns. 相似文献
436.
Mass migration is one of the most concerning potential outcomes of global climate change. Recent research into environmentally induced migration suggests that relationship is much more complicated than originally posited by the ‘environmental refugee’ hypothesis. Climate change is likely to increase migration in some cases and reduce it in others, and these movements will more often be temporary and short term than permanent and long term. However, few large-sample studies have examined the evolution of temporary migration under changing environmental conditions. To address this gap, we measure the extent to which temperature, precipitation, and flooding can predict temporary migration in Matlab, Bangladesh. Our analysis incorporates high-frequency demographic surveillance data, a discrete time event history approach, and a range of sociodemographic and contextual controls. This approach reveals that temporary migration declines immediately after flooding but quickly returns to normal. In contrast, high temperatures have sustained positive effects on temporary migration that persist over one to two year periods, while migrations decrease during extended periods of extreme precipitation. Building on previous studies of long-term migration, these results challenge the common assumption that flooding, precipitation extremes, and high temperatures will consistently increase temporary migration. Instead, our results are consistent with a livelihoods interpretation in which long-standing household livelihood strategies (both temporary migration and agriculture) are disrupted by environmental variability. 相似文献
437.
Mongolia has experienced two decades since the demise of the Soviet Union and has implemented strategies to strengthen its economy and its democratic practices. Transitions from being a nomadic society to a Soviet satellite state and onwards to liberal democracy have greatly impacted family life. The article focuses on changing patterns of mobility in the Mongolian ‘age of the market’ and its effects on population groups. Internal and international migration has continually risen as individuals and families have moved to places of opportunity. Connections are believed to be maintained during periods of absence by migrant family members, as both men and women are culturally permitted to be separate from their families. Migration is understood to contribute to prosperity, and separations contribute to generate growth and hishig (good fortune) for the good of the family. However, such mobility is also a way to escape family patriarchy and conformity, and can contribute to loss, hardship, and uncertainty for family members left behind. Further, mobility provides opportunities and a means to escape the stigma of ‘laziness’ culturally associated with poverty and immobility. Postsocialist separation has inadvertently contributed to the breakdown of the institutions of marriage and family – institutions that were supported by separations in the pastoral economy. 相似文献
438.
伽师地震与区域断层活动研究 总被引:1,自引:1,他引:0
利用GPS、连续倾斜和地震活动性资料分析了伽师地区构造活动的特点和伽师强震群的动力背景,结果表明:在印度洋板块的挤压下,塔里木盆地的右旋腑冲运动是造成南天山区地震活动的主要原因;1996年3月19日伽师阿图什6.7级地震,强烈地影响了该地区块体由向西南倾斜转向北向倾斜,并可能成为诱伽师地区强震群活动的主要动力因素,利用1998年和1999年对该地区GPS测量的结果,给出了该地区断层活动的水平。 相似文献
439.
The mobility conditions of bedload transport in an alpine high‐gradient step–pool stream (Rio Cordon) are analysed. Since 1986, a device system at the downstream end section of the stream has been operating in order to monitor the water discharge, suspended sediment and bedload transport. Sediment distribution of bedload transported by various floods has been analysed, and equal‐mobility evidence is recognized only for the high‐magnitude flows ever recorded (RI > 50 years). The thresholds for size‐selective and equal‐mobility transport conditions are identified and quantified by using both data provided by the fractional transport rate and by length displacements of marked particles. Size‐selective bedload transport seems to dominate when the critical shear stress of the size fractions τci considered is exceeded, whereas the equal‐mobility condition is approached as levels of excess shear stress become higher (τeqi = 1·45τci). Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
440.
Sarah Barns 《Urban geography》2016,37(4):554-571
Investment in the release of open data has become increasingly central to the implementation of smart city programs by governments around the world. Though originally arising out of a push towards “open government” and the pursuit of more transparent decision-making by public authorities at multiple scales, open data programs have more recently been adopted by municipal governments to support entrepreneurial goals of enhanced competitive positioning and attracting investment. As urban scholars now subject the smart city project to critical scrutiny for its role in advancing urban entrepreneurialism, this article considers the relevance of the open data agenda as it shapes wider understandings of the smart city. In particular, I address the collection of policy practices, aspirations, stakeholders and entrepreneurs active in framing the opportunities and values of open data for urban governments. Both the momentum of support for open data, along with a recent shift in the rhetorical aspirations of the open data movement away from the values of openness and transparency and towards a more confined focus on value generation, raise important critical questions for urban geographers concerned with the nature of urban governance in an age of big data. 相似文献