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181.
Ananya Roy 《Urban geography》2016,37(6):810-823
This essay takes as its provocation a question posed by the feminist philosopher Nancy Fraser: “What’s Critical about Critical Theory?” In urban studies, this question has been usefully reframed by Neil Brenner to consider what is critical about critical urban theory. This essay discusses how the “urban” is currently being conceptualized in various worlds of urban studies and what this might mean for the urban question of the current historical conjuncture. Launched from places on the map that are forms of urban government but that have distinctive agrarian histories and rural presents, the essay foregrounds the undecidability of the urban, be it geographies of urbanization or urban politics. What is at stake is a critical urban theory attentive to historical difference as a fundamental constituting process of global political economy and deconstruction as a methodology of generalization and theorization. 相似文献
182.
This paper advances recent conversations related to the need to better engage postcolonial scholarship in development geography. To do so, I bring together analytics offered by postdevelopmental, feminist geographic, and postcolonial scholarship to analyze contemporary development efforts in southeastern Turkey. To provide necessary background for the case study context, the paper considers three key moments foundational for Turkish modernist development aspirations: the foundations of the Republic through Kemalism, the emergence of Kurdish separatism and PKK resistance, and Turkish efforts to gain entry to the EU. Reading these moments, and their culmination in contemporary development efforts focused on the southeastern Anatolia region, through postdevelopmental and feminist geographic literatures invites a reading that highlights socio-spatial difference as underwriting modernist development interventions in this region. Drawing on postcolonial scholarship, particularly Bhabha’s notion of ambivalence, further enables a reading of socio-spatial difference as also undermining Turkish modernist development, signaling precisely the points where the project comes undone. The example thus lends endorsement to the need for enriched engagement between postcolonial theory, feminist and development discussions in geography, suggesting that postcolonial concepts might enable clearer focus on the ambiguities, tensions, and contradictions inherent to development geographies. 相似文献
183.
A qualitative Natech damage scale for the impact of floods on selected industrial facilities 总被引:4,自引:2,他引:2
There is increasing evidence that natural disasters can trigger technological accidents and damage. These so-called Natech
accidents can pose a significant risk to regions that are unprepared for responding to them. The European Commission’s Joint
Research Centre has recognised the risk associated with Natech events and has started systematic research into Natechs and
their underlying dynamics. This work investigates the risk associated with the flooding of industrial installations through
an analysis of past case histories and using expert judgement. The potential impact of three levels of flood severity on selected
industrial facilities storing and/or processing (eco-)toxic, flammable or explosive materials is analysed qualitatively and
a scale is developed that links the flood intensity to the level of potential damage. Our analysis indicates that natural
disasters have the potential for triggering hazmat releases and other types of technological accidents. Hence, natural disasters
should be considered as separate accident-triggering events in the planning, design and operating stages of industrial facilities
that process or store hazardous substances. Our work revealed a lack of detailed information on the occurrence of Natech events
which indicates not necessarily a scarcity of Natechs but rather a lack of standardised reporting and record keeping. 相似文献
184.
Cut Slopes in Clayey Soils: Consolidation and Overall Stability by Finite Element Method 总被引:1,自引:1,他引:0
José Leitão Borges 《Geotechnical and Geological Engineering》2008,26(5):479-491
When a cut slope in a saturated clay is undertaken, a transient water flow occurs and stress transferences from the water
to the soil skeleton take place in time (consolidation). Mainly in strongly overconsolidated clays, these stress transferences
may determine swelling of soil and therefore reduction of its shear strength in time. However, the lowering of the water level
associated to the cut increases effective mean stress, which may therefore counterbalance the above-mentioned effect. In the
paper, the behaviour of a cut slope in an overconsolidated clay is analysed by a finite element program that incorporates
the Biot consolidation theory (coupled analysis), with constitutive relations simulated by the p–q–θ critical state model. In addition, the variation in time of the overall stability is assessed with a computer program that
uses the finite element results and formulations of the critical state soil mechanics. In order to achieve a more complex
geotechnical interpretation of the problem, the analysis in time of the excess pore pressures, effective stresses, displacements
and stress levels is also presented. Finally, comparisons of stability results are analysed by changing some parameters, namely
the problem geometry (weight of excavated soil) and the over-consolidation ratio of the clay. 相似文献
185.
The long-term integrity of CO2 storage in deep saline aquifers has become uncertain due to the unsteady character of surrounding factors, and the time-dependent nature of the aquifer's overburden load (the vertical stress imposed on the aquifer by the weight of overlying materials (rock/soil layers), which may vary over time as a result of natural incidents such landslides and earthquakes) is critical. The aim of this study is to identify the influence of overburden load variations on the long-term integrity of the CO2 storage process in deep saline aquifers. High-pressure tri-axial strength and permeability tests, along with acoustic emission (AE) and scanning electron microscopy (SEM) analyses, were conducted on Hawkesbury sandstone obtained from the Gosford basin.According to the results, the injection of CO2 into the Hawkesbury formation may dissolve aquifer rock minerals, enhancing aquifer flow performance and reducing aquifer strength. Increasing the stress applied on the aquifer causes aquifer flow ability to reduce to some extent due to pore matrix compaction. Further increase of the overburden pressure may accelerate the aquifer's flow performance due to dilation-induced pore opening. This permeability transition point occurs earlier at greater CO2 injection pressures and overlaps with the crack formation point of the aquifer rock mass. Therefore, weakening of the rock mass after the transition point can be expected. Importantly, this permeability transition point occurs at lower overburden loads after longer interaction of CO2 with the saline aquifer. This exhibits the long-term risk associated with CO2 sequestration in saline aquifers. Permeability enhancement after the transition point may also produce environmental disasters, such as sudden leakages of injected CO2 from the reservoir to surrounding fresh water aquifers (Evans et al. 2004; Little and Robert 2010), exceeding the specific rates proposed by many regulatory frameworks. Therefore, it is essential to study the long-term integrity of the sequestration process in order to develop a regulatory structure to meet the demands of deep saline sequestration projects. 相似文献
186.
Large-eddy simulation of turbulent flow past a circular cylinder at sub- to super-critical Reynolds numbers is performed using a high-fidelity orthogonal curvilinear grid solver. Verification studies investigate the effects of grid resolution, aspect ratio and convection scheme. Monotonic convergence is achieved in grid convergence studies. Validation studies use all available experimental benchmark data. Although the grids are relatively large and fine enough for sufficiently resolved turbulence near the cylinder, the grid uncertainties are large indicating the need for even finer grids. Large aspect ratio is required for sub-critical Reynolds number cases, whereas small aspect ratio is sufficient for critical and super-critical Reynolds number cases. All the experimental trends were predicted with reasonable accuracy, in consideration the large facility bias, age of most of the data, and differences between experimental and computational setup in particular free stream turbulence and roughness. The largest errors were for under prediction of turbulence separation. 相似文献
187.
188.
The false Basel earthquake of May 12, 1021 总被引:1,自引:0,他引:1
Gabriela Schwarz-Zanetti Virgilio Masciadri Donat Fäh Philipp Kästli 《Journal of Seismology》2008,12(1):125-129
The Basel (CH) area is a place with an increased seismic hazard. Consequently, it is essential to scrutinize a famous statement by Stumpf (Gemeiner loblicher Eydgnoschafft Stetten, Landen und Völckeren Chronikwirdiger thaaten beschreybung. Durch Johann Stumpffen beschriben, 1548) that allegedly a large earthquake took place in Basel in 1021. This can be disproved unambiguously by applying historical and philosophical methods. 相似文献
189.
Lethal temperature tolerance was determined for about 8 cm, age 0 Pseudosciaena crocea using both slow heating and rapid transfer protocol. The acclimatization temperature was 28 ℃ with summer season, lethal temperature ( LT50 value ) of slow heating protocol ( CTMax ) was 35.0 ℃, and the upper and lower incipient lethal temperatures of rapid transfer protocol were 34.2 ℃ and 17.5 ℃ respectively. 相似文献
190.
加卸载响应比与应变能加速释放的临界现象讨论 总被引:2,自引:0,他引:2
对发生在中国大陆地区的8次地震, 用不同的区域半径分别进行应变能释放的幂率拟合和加卸载响应比计算, 发现最佳幂率拟合的区域半径与加卸载响应比最大值所对应的区域半径的对数与地震的震级呈线性关系, 且两者具有很好的一致性, 因而认为两者之间可能具有相同的物理机制, 是孕震系统进入临界状态的不同表现形式。 相似文献