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Public policy frequently is utilised as a medium to facilitate or restrict access to public space, and to privilege economic priorities. In this context urban arts festivals are used as a means to generate dominant narratives of place and use of public space. Urban arts festivals generate spaces of spectacle and wonder, and are often used as marketing strategies to revitalise urban economies and differentiate cities one from another on the global stage, engendering a commodification of place. The present paper explores this tension through an examination of the role of urban arts festivals in spatial politics. White Night Melbourne is the first Australian iteration of the Nuit Blanche International, an international network of all-night arts festivals. It is used as a case study to explore the impact of an urban arts festival on the spatial politics of Melbourne. A theoretical basis is established using the frame of Guy Debord's ([1967] 1994) The Society of the Spectacle, as well as the concepts of ‘assemblage’ and ‘expressivity’. 相似文献
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The defense meteorological satellite program (DMSP) operational linescan system (OLS) sensors have imaged emitted light from Earth's surface since the 1970s. Temporal overlap in the missions of 5 OLS sensors allows for intercalibration of the annual composites over the past 19 years (Elvidge et al., 2009). The resulting image time series captures a spatiotemporal signature of the growth and evolution of lighted human settlements and development. We use empirical orthogonal function (EOF) analysis and the temporal feature space to characterize and quantify patterns of temporal change in stable night light brightness and spatial extent since 1992. Temporal EOF analysis provides a statistical basis for representing spatially abundant temporal patterns in the image time series as uncorrelated vectors of brightness as a function of time from 1992 to 2009. The variance partition of the eigenvalue spectrum combined with temporal structure of the EOFs and spatial structure of the PCs provides a basis for distinguishing between deterministic multi-year trends and stochastic year-to-year variance. The low order EOFs and principal components (PC) space together discriminate both earlier (1990s) and later (2000s) increases and decreases in brightness. Inverse transformation of these low order dimensions reduces stochastic variance sufficiently so that tri-temporal composites depict potentially deterministic decadal trends. The most pronounced changes occur in Asia. At critical brightness threshold we find an 18% increase in the number of spatially distinct lights and an 80% increase in lighted area in southern and eastern Asia between 1992 and 2009. During this time both China and India experienced a ∼20% increase in number of lights and a ∼270% increase in lighted area – although the timing of the increase is later in China than in India. Throughout Asia a variety of different patterns of brightness increase are apparent in tri-temporal brightness composites – as well as some conspicuous areas of apparently decreasing background luminance and, in many places, intermittent light suggesting development of infrastructure rather than persistently lighted development. Vicarious validation using higher resolution Landsat imagery verifies multiple phases of urban growth in several cities as well as the consistent presence of low DN (<∼15) background luminance for many agricultural areas. Lights also allow us to quantify changes in the size distribution and connectedness of different intensities of development. Over a wide range of brightnesses, the size distributions of spatially contiguous lighted area are consistent with power laws with exponents near −1 as predicted by Zipf's Law for cities. However, the larger lighted segments are much larger than individual cities; they correspond to vast spatial networks of contiguous development (Small et al., 2011). 相似文献
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１９９６年１月～１９９８年３月,我们用光电方法测定了丽江高美古在Ｂ、Ｖ两个波段的夜天光亮度。为便于比较,在１９９６年１月还测定了云南天文台凤凰山台址的夜天光亮度。本文给出了观测结果,同时也列出了世界上一些天文台站的数据以供参考。 相似文献
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重力波是中间层大气的重要能量来源,气辉观测为研究中间层重力波特性提供了极好的方法。本文利用最新的 OH 气辉激发机制,建立了一个较完整的光化、动力模式来分析重力波传播对 OH 气辉的影响。结果表明,化学反应速率系数不定性对 Krassovsky 比振幅的影响较小,但淬灭过程的影响必须考虑。Krassovsky 比的振幅和相位均依赖于波周期,其振幅在2.1和10.3之间变化;这表明 OH 气辉亮度的相对变化大于温度的相对变化。一般情况下,重力波引起的温度扰动超前于气辉亮度的变化。与实测资料比较发现,两者变化趋势基本一致,在短周期波时吻合较好。 相似文献
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Ionospheric conductivity is not very easily measured directly. Incoherent scatter radars perhaps offer the best method but can only measure at one point in the sky at any one time and are limited in their time resolution. Statistical models of average conductivity are available but these may not be applied to individual case studies such as substorms. There are many instances where a real-time estimate of ionospheric conductivity over a large field-of-view is highly desirable at a high temporal and spatial resolution. We show that it is possible to make a reasonable estimate of the noctural height-integrated Pedersen conductivity, or conductance, with a single all-sky TV camera operating at 557.7 nm. This is not so in the case of the Hall conductance where at least two auroral wavelengths should be imaged in order to estimate additionally the energy of the precipitating particles. 相似文献
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利用夜间灯光遥感数据和POI数据,采用断裂点分析法得出城市实体地域的范围大小。在此基础上引入交通便利系数和相对引力常量修正引力模型,分析广佛都市区内部各个城市实体地域间的引力强度和方向。结果表明：1）广佛都市区形成了以核心区为中心的“7+1”城镇体系结构;2）“七边形”正向城市体系结构围绕核心区域生成,“六边形”负向城市体系结构围绕西南区域生成,“西强东弱”格局明显;3）城市三角结构是广佛城市引力结构的基本单元,发展较好的城市组团为“核心区—顺德—南沙”“核心区—顺德—高明”“核心区—三水—花都”“核心区—花都—从化”,而“核心区—增城—南沙”和“核心区—高明—三水”组团则发展动能不足;4）广佛都市区引力势能大小及结构稳定与城市经济职能强度正相关。 相似文献
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Auroral and airglow emissions over Eureka (89° CGM) during the 1997/98 winter show striking variations in relation to solar wind IMF changes. The period January 19 to 22, 1998, was chosen for detailed study, as the IMF was particularly strong and variable. During most of the period, Bz was northward and polar arcs were observed. Several overpasses by DMSP satellites during the four day period provided a clear picture of the particle precipitation producing the polar arcs. The spectral character of these events indicated excitation by electrons of average energy 300 to 500 eV. Only occasionally were electrons of average energy up to 1 keV observed and these appeared transitory from the ground optical data. It is noted that polar arcs appear after sudden changes in IMF By, suggesting IMF control over arc initiation. When By is positive there is arc motion from dawn to dusk, while By is negative the motion is consistently dusk to dawn. F-region (anti-sunward) convections were monitored through the period from 630.0 nm emissions. The convection speed was low (100/150 m/s) when Bz was northward but increased to 500 m/s after Bz turned southward on January 20. 相似文献