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1.
What is the relationship between the direction and form of an energy transition and the political economy within which it is embedded? This paper explores how the nature of (low carbon) energy transitions is strongly influenced by the process of neoliberalisation that shape energy policy in the South. We seek to understand emergent energy transitions and to advance their theorisation through an account of the political economy of energy transition in Kenya. In contrast to the often techno-managerial orientation of literatures on socio-technical transitions, we explore the political terrain upon which competing visions of energy futures and material interests collide and seek to accommodate one another. We develop a political economy account that emphasises the structural and disciplinary power of capital and global institutions to set the terms of transition. This expresses itself in both delimiting the autonomy of state actors and by reconfiguring domestic institutional and social power in ways that shape the distributional politics of transitions.  相似文献   

2.
Sally Eden  Christopher Bear 《Geoforum》2008,39(2):1044-1057
This paper uses evidence from focus groups in England to consider how consumers think about and, more importantly, distinguish foods by both primary and secondary qualities, using both their own judgement but also advice produced by various organisations acting as ‘knowledge intermediaries’, such as independent certification bodies. We thus consider the ‘sorting out’ that consumers do with food, particularly in developing typologies of ‘goodness’ and ‘badness’, and the cues on which they base these judgements, from the material immediacy of ‘mucky carrots’ to the abstract remoteness of organic certification. In particular, we problematise the ‘knowledge-fix’ that underlies attempts to provide knowledge to promote more sustainable and ethical consumption. This raises problems of how consumers give assurance schemes meaning, how ethical and sustainable schemes are subject to re-fetishization and how consumers tend towards increasing scepticism and distrust of such claims, thus making a ‘politics of reconnection’ far from easy.  相似文献   

3.
Family and youth research has highlighted the importance of lifecourse transitions, illustrating how they can have a substantial impact on people’s everyday lives and anticipated futures. Given their apparent significance, it is surprising that relatively little attention has been paid to life transitions – particularly unexpected ones – to explore how they can impact upon everyday energy use. This is a central concern of Energy Biographies project. The project’s qualitative longitudinal design makes an original contribution, affording a detailed view of how transitions unfold and their significance for energy demand and environmental action. Central to elucidating these issues is the concept of ‘linked lives’, recognising that people live interdependently. In this paper, we explore the accounts of three participants who experienced one or more life transitions during the course of the project, in order to consider the impacts of these events (both planned and unanticipated) on their everyday energy use and environmental actions as part of their linked lives with others.  相似文献   

4.
One of the major challenges of moving toward more sustainable and water sensitive futures is to change people's everyday water consumption habits. The experience of the Millennium drought in Australia (1996–2010) and water restrictions introduced during that time intervened to change everyday water practices in specific ways creating durable change in some practices and mutable change in others. Drawing on focus groups with 62 people, in three diverse Australian cities, a rich picture of diverse water practices emerges. Using a specific social practice framework we explore the key practices of garden watering and showering and tease out the elements in each – we discuss how and why there has been more innovation and change in garden practices than shower practices. We argue that sustained water restrictions drive material change in households and these material changes appear to be more effective in changing water use than transforming water saving competencies or meanings alone. Further, we show that the commitment and resistance to water saving has a spatial context – data from three different cities allowed us to see how location, climate and policy responses interweave with everyday practices. The implication of our research is that policy interventions should be 'fit for purpose' according to social practices in spatial context.  相似文献   

5.
A large amount of buildings was damaged or destroyed by the 2011 Great East Japan tsunami. Numerous field surveys were conducted in order to collect the tsunami inundation extents and building damage data in the affected areas. Therefore, this event provides us with one of the most complete data set among tsunami events in history. In this study, fragility functions are derived using data provided by the Ministry of Land, Infrastructure and Transportation of Japan, with more than 250,000 structures surveyed. The set of data has details on damage level, structural material, number of stories per building and location (town). This information is crucial to the understanding of the causes of building damage, as differences in structural characteristics and building location can be taken into account in the damage probability analysis. Using least squares regression, different sets of fragility curves are derived to demonstrate the influence of structural material, number of stories and coastal topography on building damage levels. The results show a better resistant performance of reinforced concrete and steel buildings over wood or masonry buildings. Also, buildings taller than two stories were confirmed to be much stronger than the buildings of one or two stories. The damage characteristic due to the coastal topography based on limited number of data in town locations is also shortly discussed here. At the same tsunami inundation depth, buildings along the Sanriku ria coast were much greater damaged than buildings from the plain coast in Sendai. The difference in damage states can be explained by the faster flow velocities in the ria coast at the same inundation depth. These findings are key to support better future building damage assessments, land use management and disaster planning.  相似文献   

6.
刘中宪  齐欣  王冬  柴寿喜  姚殊 《岩土力学》2018,39(10):3803-3811
众多城市坐落于沉积河谷之中,沉积河谷-密集建筑群间的地震动力相互作用规律尚不明确。采用间接边界元方法(IBEM),对在平面SV波入射下,沉积河谷-建筑群之间的地震相互作用进行二维模拟计算和参数分析。研究结果表明:沉积河谷-建筑群间存在着显著而复杂的地震动力相互作用;较浅沉积河谷中建筑群地震响应呈现强弱交替变换特征;入射波角度、沉积河谷的材料、几何特征是影响沉积河谷-建筑群整体地震响应规律的关键因素。总体上看,建筑群对浅沉积河谷地震动响应有较大的降幅效应,特别是高频波入射下最大降幅近50%。实际河谷地震放大效应评估需考虑密集建筑群的影响,而位于地震波聚焦位置的建筑物需适当提高设防标准。  相似文献   

7.
本文采用自主设计的地面振动加速度监测系统对3个不同土性场地的钢板桩施工进行了现场监测,分析了钢板桩施工过程中的地面振动峰值加速度和振动频率特性,并探讨了振动衰减规律及对周边建筑物的影响。研究结果表明:土的强度对钢板桩施工振动的影响显著,钢板桩在低阻力土体中的贯入速率快,地面振动响应弱,而在高阻力的土体中贯入速率慢,地面振动相对大很多;钢板桩施工引起的地面径向和切向加速度在同一深度比较接近,且随着深度的增加有增大的趋势;振源距离和土性对钢板桩施工引起的地面振动主频率影响不大,地面振动主频率与桩锤施工频率之间呈较好的线性正相关关系;钢板桩施工振动在距振源4 m范围内衰减迅速,其施工对周围建筑物的最小安全距离要远小于挤土型桩基的施工。  相似文献   

8.
The quality of aggregate used as buildings materials is defined by European Standard test methods. According to the agreement within the European Economic Area, each individual country decides test methods of current interest. Among the Nordic countries, the Los Angeles-, micro-Deval- and the Nordic test are the most common methods used to decide the mechanical properties of the aggregate. The three test methods are all drum test where the degradation of the material occur by rotation between the test material and steel balls together with, or without water. The mechanical test methods are empirical and are believed to express either resistance to fragmentation or wearing. The results of this study show that analysing the particle size distribution of a material after the drum testing give indication of which type and degree of degradation the test material is exposed to. Knowledge of the type of degradation for the test methods is important compared to the understanding of the real breakdown of the aggregate for instance used in road construction.  相似文献   

9.
热反射技术是一项被广泛应用于建筑物及道路表面降温的主动冷却技术, 国内外很少对此技术在多年冻土区道路热保护方面进行研究。针对多年冻土区气候及工程环境特点, 综述了热反射技术在冻土区道路中的应用现状和研究成果, 阐述了热反射涂层的基本成分、 反射机理和测试方法, 分析了路用热反射涂层的材料性能、 反射效果和路用性能, 简要介绍了热反射涂层在路基边坡应用方面的研究进展。指出在当前条件下利用热反射涂层保护多年冻土区道路所遇到的问题及可行的解决方案, 并在此基础上提出了今后研究的重点: 从材料选择、 理论分析和试验方法入手, 对路用热反射涂层的颜色、 反射性能、 路用性能和区域适用性进行改进和研究, 加强多年冻土区道路热反射涂层的野外试验和分析, 深入研究复杂气候和工程环境下的热反射涂层性能。  相似文献   

10.
Thirteen years since the EU Habitats Directive (1992/43/EEC) became a binding legal agreement, this paper considers the implementation of this important European environmental legislation as it applies to the coastal activities of seaports and harbours. The paper examines the relationship between environmental legislation and ports policy, and seeks to provide a comprehensive assessment of the policy and science that has been developed in relation to protected areas and port management. The paper reports the results of a survey of European port professionals, and their perception of the successes and challenges of the management regimes that have been established, as well as their opinions on how these have influenced the management within ports. The paper also provides a detailed examination of the scientific and technical developments with particular regard to dredging and habitat management in European ports. Key research gaps are identified, including: practical approaches to licensing procedures; lack of baseline information, especially with regard to in-combination effects; the efficacy of techniques for mitigating the impacts of dredging; and greater understanding on how more resilient models for collaborative action can be developed. The paper will be of use to environmental planners, scientists, regulators, conservationists, and port managers, as they consider how to apply science and management to the sustainable development and environmental protection of coastal areas.  相似文献   

11.
Unified modelling of granular media with Smoothed Particle Hydrodynamics   总被引:1,自引:1,他引:0  
In this paper, we present a unified numerical framework for granular modelling. A constitutive model capable of describing both quasi-static and dynamic behaviours of granular material is developed. Two types of particle interactions controlling the mechanical responses, frictional contact and collision, are considered by a hypoplastic model and a Bagnold-type rheology relation, respectively. The model makes no use of concepts like yield stress or flow initiation criterion. A smooth transition between the solid-like and fluid-like behaviour is achieved. The Smoothed Particle Hydrodynamics method is employed as the unified numerical tool for both solid and fluid regimes. The numerical model is validated by simulating element tests under both quasi-static and flowing conditions. We further proceed to study three boundary value problems, i.e. collapse of a granular pile on a flat plane, and granular flows on an inclined plane and in a rotating drum.  相似文献   

12.
Through a critique of existing regeneration literatures the paper points to the close relationship between regeneration and sustainable development. It suggests that the economic aspects of sustainable development have tended to dominate: leading to the neglect of nature in both regeneration and sustainable development, with regeneration having a principal focus on socio-economic issues in urban settings. To address these lacunae we suggest the need for a more environmentally sensitive regeneration theory. Using this approach the paper draws on recent in-depth research in three post-industrial coalfield areas where regeneration processes operate in the form of community forest projects. It provides a critical perspective on these regeneration processes, integrating theory with empirical data and highlighting how nature is drawn into broader economic and social processes of regeneration. In conclusion, using forestry initiatives as examples, we reflect on the conceptual dissonance apparent in regeneration theory and practice, and point to theoretical insights that could enable a more critical regeneration theory; more beneficial outcomes to regeneration processes; and an improved understanding of the relations between nature, capital and community in regeneration processes and sustainable development.  相似文献   

13.
近些年来,越来越多的学者开始关注人类的可持续发展问题,而与之有着密切关系的承载力理论研究可以说是人类研究可持续发展战略的一个分支.本文以长江三角洲地区为研究区,着重介绍了如何用元胞自动机和神经网络相结合的方法对区域承载力进行定量分析,希望对长三角地区的可持续发展提供一些理论依据.  相似文献   

14.
This research is located at the intersection of three canals in periurban Gurugram. Two of these canals were built to provide water for the growing city of Gurugram and one of them carries the wastewater of the city back to the villages. These canals cut through periurban villages that are excluded in principle from taking benefit of these canals. They are meant to be at their receiving end, as recipients of these waters. The paper, using a socio-technical lens, explores the mixed impacts of these canals on the villages through which they traverse. The paper further describes the strategies that periurban communities devise to circumvent the situation of exclusion. Using a qualitative, ethnographic research design, the paper describes the socio-technical mediation of periurban water insecurity, focusing on the mix of technologies and institutions that spring up around these canals that shape the periurban water users’ access to water. The paper concludes that approaches for promoting community resilience and periurban water security need to start from an understanding of the strategies devised by periurban communities to improve their access to water. In the larger discourse on building community resilience in the face of urbanization and climate change it is important to pay attention to local norms of cooperation that enable periurban communities to access water, rather than start from a premise that water insecurity caused by urbanization and climate change will lead to conflicts or necessitate capacity-building to promote avoid conflict and promote cooperation.  相似文献   

15.
Soil shearing resistance is very important while designing various structures which have direct contact with soil, for example, sheet piles, piles, retaining walls, reinforced earth structures and shallow foundations. Even though designers use empirical values for their design, it is very important to obtain more accurate values for soil–solid materials shearing resistance. In this work, laboratory tests have been carried out to investigate the effect of roughness interface and texture models on friction angle between cohesive soils and steel, as well as abrasive paper material, using direct shear tests. All tests were carried out under consolidated drained shear conditions. The behavior at the soils–solid interface was found to vary according to surface roughness. It also seems that the type of material (steel or paper of abrasive) used does not have a major influence on the shear strength. As far as roughness is concerned, friction behavior is likely to be generally classified into three failure modes, namely full sliding at the interface, shear failure within the soil, and a mixed behavior where interface sliding and shear deformation of the soil specimen proceed simultaneously. However, for the second mode, the shear strength at the interface soil-rough solid materials steel was found to be lower than the shear strength of the soil, for a soil that is classified as high plasticity clay. Furthermore, it was found that the interfacial shear strength is independent of the texture surface for a given roughness.  相似文献   

16.
根据建筑物不均匀震陷发生机制,提出了建筑物不均匀震陷二维有限元分析方法。采用了不规则荷载下土的残余应变模型及土体逐步软化模型,考虑了土、结构及地震动波形对不均匀震陷的协同作用效果,实现了对建筑物不均匀震陷的时程分析,并通过大型振动台试验对方法的可靠度进行了检验。  相似文献   

17.
Asia, and in particular the Mekong Delta region, is under increasing water use pressure. Food production and quality is one element of these growing pressures, as is water management. The authors have first-hand knowledge and experience in groundwater use and management in rural Thailand. Through the adoption of a micro-management, demand-driven approach, with its ultimate objective of sustainability and the betterment of the quality of human life, the Mekong delta and other similar rural areas in Asia offer considerable opportunity for more optimal sustainable exploitation of groundwater. This water source should be prioritized for village usage, which if properly allocated and managed, will lift a significant human population from poverty, into a more sustainable existence. This readily available, reliable groundwater resource exists and has both the capacity for abundant storage as well as the potential for commercial and household supply. The focus has been on understanding the distribution of the delta’s relatively shallow, well sustained, and consistently recharged groundwater resource, and its potential symbiotic linkage to low-volume household demand. Water has been employed in a variety of ways from improving quality of life and sanitation to generating income through the cultivation of cash crops and other similar productive uses. The fundamental aims of the initial model and subsequent trials have been to harness this robust water source and deliver otherwise unattainable income to households. As the following, more detailed study of rural Thailand demonstrates, the benefits of such an approach deliver sustainable enhancements to the quality of constituents’ lives, are environmentally sensitive and sustainable, and harmonize with governmental efforts to alleviate poverty through the enablement of income generation from groundwater utilization.  相似文献   

18.
通过对Q420高强钢的材料性能分析及在输电杆塔的应用现状了解,根据线路新的规程规范对杆塔荷载的要求,在本次河南省钢管杆典型化设计中局部采用Q420高强钢做为主材,对其强度及挠度进行分析,并同时采用传统塔材进行比对,结果表明,受力较大的钢管杆采用Q420高强钢时,能节约钢材量,且提高了杆塔使用强度,体现了“两型三新”输电线路建设的宗旨。  相似文献   

19.
Landslide susceptibility and hazard assessments are the most important steps in landslide risk mapping. The main objective of this study was to investigate and compare the results of two artificial neural network (ANN) algorithms, i.e., multilayer perceptron (MLP) and radial basic function (RBF) for spatial prediction of landslide susceptibility in Vaz Watershed, Iran. At first, landslide locations were identified by aerial photographs and field surveys, and a total of 136 landside locations were constructed from various sources. Then the landslide inventory map was randomly split into a training dataset 70 % (95 landslide locations) for training the ANN model and the remaining 30 % (41 landslides locations) was used for validation purpose. Nine landslide conditioning factors such as slope, slope aspect, altitude, land use, lithology, distance from rivers, distance from roads, distance from faults, and rainfall were constructed in geographical information system. In this study, both MLP and RBF algorithms were used in artificial neural network model. The results showed that MLP with Broyden–Fletcher–Goldfarb–Shanno learning algorithm is more efficient than RBF in landslide susceptibility mapping for the study area. Finally the landslide susceptibility maps were validated using the validation data (i.e., 30 % landslide location data that was not used during the model construction) using area under the curve (AUC) method. The success rate curve showed that the area under the curve for RBF and MLP was 0.9085 (90.85 %) and 0.9193 (91.93 %) accuracy, respectively. Similarly, the validation result showed that the area under the curve for MLP and RBF models were 0.881 (88.1 %) and 0.8724 (87.24 %), respectively. The results of this study showed that landslide susceptibility mapping in the Vaz Watershed of Iran using the ANN approach is viable and can be used for land use planning.  相似文献   

20.
We consider the phase transitions in tridymite from the perspective of the rigid unit mode model. The rigid unit modes are the low-frequency phonons of a crystal structure that consists of an infinite framework of tetrahedra linked at corners, that can propagate without the tetrahedra distorting. Because they give distortions of the structure with a low energy cost they are the natural soft modes for displacive phase transitions. We consider the normal phase transition sequence in tridymite on cooling, HP LHP ..., as a successive condensation of rigid unit modes acting as soft modes. Some of the low-temperature phases (e.g. MX-1) arise as rigid unit mode distortions of the high-temperature structure and do not follow the sequence of phases found at higher temperatures. We are able to account for all the commensurate phases and some of the modulated phase within the framework of the rigid unit mode model. Received: 20 April 1998 / Accepted: 3 September 1998  相似文献   

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