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81.
Kameshwari Pothukuchi Jerome L. Kaufman 《Journal of the American Planning Association. American Planning Association》2013,79(2):113-124
Shelley Jordon describes her artwork as celebrating “the power and the beauty of domestic spaces and objects…culled from daily life.” Food is among the most basic of daily human needs, yet what is most basic often gets overlooked. Alpenrose, her image of a breakfast table, brings this human need to the fore, as authors Ka-meshwari Pothukucki and Jerome L. Kaufman argue that food systems need a place among the concerns of planners. The artist, who is an associate professor of art at Oregon State University, resides in Portland, Oregon. Her works can be found in galleries and private collections throughout the West Coast. Planning lays claim to being comprehensive, future-oriented, and public-interest driven, and of wanting to enhance the livability of communities. It is concerned with community systems—such as land use, housing, transportation, the environment, and the econ-omy—and their interconnections. The food system, however, is notable by its absence from most planning practice, research, and education. We present evidence for the limited presence of the food system in planning's list of concerns by scanning leading journals, texts, and classic writings, and by reporting on a survey of 22 U.S. city planning agencies. We analyze this low level of attention and discuss reasons and ideas for planning involvement to strengthen community food systems.1 相似文献
82.
By applying the Lefebvrian lens, this paper tries to understand why unlike previous similar cases, the latest removal of the Star Ferry and Queen’s Pier was so controversial. To Lefebvre, embedded in ‘spatial practices’ that ‘secrete’ a place are two contradicting spaces: ‘conceived spaces’ produced by planners to create exchange values and ‘lived spaces’ appropriated by citizens for use values. Applying Lefebvre’s framework to examine the ‘Piers saga’, it is found that the pre‐Second World War (WWII) piers were ‘conceived’ by spatial practices of a colonial and racially segregated trading enclave. The public space in the commercial heart that housed the previous generations of piers was not accessible to the Chinese community, thus denying them opportunities to appropriate them and turn them into ‘lived’ spaces. It was only after WWII when the Government carried out further reclamation to meet the needs of an industrializing economy that inclusive public spaces were conceived in the commercial heart, enabling the general public to ‘appropriate’ them as ‘lived’ space. When the Government planned to remove this very first ‘lived’ space in the political and economic heart of the city to conceive further reclamation for the restructuring economy, the more enlightened citizens were determined to defend it. 相似文献
83.
通过对汶川地震公路隧道震害调查资料的统计分析,对隧道洞口结构进行了震害分析,结果表明:洞外结构受次生灾害影响较大,地震惯性力影响明显;硬岩洞口段隧道结构基本无破坏,软岩洞口段隧道结构震害较严重。通过三维有限差分数值模拟计算和现场典型震害分析,研究了公路隧道洞口结构的震害机理。探明了洞外结构震害机理,即洞外结构受次生灾害影响较大,震害的主要原因是地震惯性力,洞门墙结构和基础设计不合理以及隧道洞口所处位置也是影响洞外结构震害的重要因素。探明了洞口段隧道结构震害机理,即正穿坡面洞口段隧道结构存在软硬围岩交界面时,其附近软岩内隧道结构受较大强制位移作用;正穿坡面洞口段隧道结构覆盖层为软岩时,震害的主要因素是地震惯性力。研究成果对公路隧道洞口结构的抗减震技术有着重要的意义。 相似文献
84.
《Cities》2019
Many cities in China are undergoing large-scale demolition of urban villages. The difficulty of finding suitable housing for migrant workers has caused widespread concern because the lack of proper housing may lead to the outflow of migrant workers that would affect the normal operation of the city. Based on data collected by questionnaire survey in Hangzhou and a multivariate logistic model, this study analyzed the influence of housing demolition on the housing choices of migrant workers. We found that nearly a third (29.2%) of migrant workers spend >30% of their income on rent, and 14.1% of migrant workers plan to return to rural areas. This means that migrant workers face significant housing pressure and some migrant worker outflow from the city exists. Further empirical analysis corroborates that nine variables—including gender, age, education, marriage, occupation, RIR, RRS, HCW, and CMW—have a significant impact on migrant worker housing choices. Based on the results of multivariate logistic regression analysis, we recommend that the government expand the coverage of public rental housing, build temporary low-rent housing, stimulate businesses to provide housing subsidies to their workers, improve the educational conditions for migrant children, and intensively develop long-term, low-income rental apartments. 相似文献
85.
《Cities》2019
Building on the critical resilience literature, this study aims at analyzing how the community resilience (CR) of urban village (UV), which is challenged by multiple natural and socio-economic disturbances such as climate change, land occupation, and industrialization, responses to the government-led redevelopment (GLR) and its hidden mechanism. A conceptual framework incorporating social, economic, institutional/governmental, material domains and community capital was established with reference to the work of Cutter, Burton, and Emrich (2010), and was applied as the conceptual springboard to assess the resilience of Tangjialing village. The results suggested that the GLR in Tangjialing village was generally a successful practice for enhancing CR, which was tightly associated with the economic empowerment for local residents and formalization of informal economic activities and negatively affected by insufficient public engagement. Accordingly, policy implications about enhancing the resilience such as protecting the farmers' “private rights” as landowners, providing employment guidance and assistance and implementing cooperative planning were proposed. 相似文献
86.
《Cities》2019
Urban planning, design guidelines and new management practices have radically transformed public spaces in many countries. With fresh development decisions, urban spaces change spatially. This may improve places, increasing prosperity and extending expectations of modernization in many cities. However, widespread public disillusion and failures to produce environments reflecting local values can collectively shape public areas. This article contributes to debate about dynamism in such spaces. It explores how modernist approaches to planning and design alongside fractures in management practices in emerging cities have shaped the quality urban space. We use Jeddah as a radically re-planned city in a rapidly developing economy, but one where largely unusable public spaces have failed to meet people's everyday needs and aspirations. Our investigation – based on extensive literature reviews, documentary analyses, morphological survey, photographic and qualitative surveys – provides a better understanding of the role of a proactive urban design for promoting environmental quality. This helps resolve the multiple challenges confronting public space provision. 相似文献
87.
《Cities》2019
Population migration, social check-in, vehicle navigation, and other spatial behavior big data have become vital carriers characterizing users' spatial behavior. “Tencent Migration” big data can real-timely, dynamically, completely and systematically record population flow routs using LBS device. Through gathering residents daily mobility among 299 cities in China during the period of “National Day–Mid-Autumn Festival” (NDMAF) vacation (from September 30 to October 8) in 2017 in “Tencent Migration” and defining three periods with “travel period, journey period, return period”, this paper is designed to analyze and explore the characteristics and spatial patterns of daily flow mobility cities from the perspective of population daily mobility distribution levels, flow distribution layers network aggregation, spatial patterns and characteristics of the complex structure of the flow network. Results show that “Tencent migration” big data clearly discovers the temporal-spatial pattern of population mobility in China during the period of NDMAF. The net inflow of population showed a diamond shaped with cross frame support in each period, the four nodes of the diamond contain Beijing, Shanghai, Guangzhou and Xi'an. Main mobility assembling centers are distributed in the urban agglomerations of Beijing-Tianjin-Hebei, Yangtze River Delta, Pearl River Delta and Chengdu-Chongqing, and those centers have strong coherence with those urban hierarchies. Most cities are in a state of “relative equilibrium” in the population flow, and clear hierarchical structure and level distinction can be identified. Spatial patterns of population mobility present obvious core-periphery structures. The Dali-Hegang line exhibits a significant network of spatial differences in terms of boundary divisions. In this context, the spatial distribution of urban network could be summarized as “dense in the East and sparse in the West”, and the core linkages of urban network could be characterized as “parallel in the East and series in the West”. The whole network exhibits a typical “small world” network characteristic, which shows that China's urban population flow network has high connectivity and accessibility during the period of NDMAF. The network has a distinct “community” structure in the local area, including 2 national communities, 2 regional communities and 3 local-level communities. 相似文献
88.
《Cities》2019
The micro-level urban morphology of large cities in the Middle East and North Africa and southeastern Europe has not been thoroughly investigated, and its transformation during the past decades has remained less-studied. Hence, this study is meant to partially explain urban morphology of Istanbul, Cairo, and Tehran, three megacities of the region by focusing on the historical neighborhood typologies of the past century. The overall aim of this study is to address the feedbacks of historical urban transformations during the past 100 or 150 years to some important aspects of livability like mobility and social interactions. The objectives are to define the typologies of neighborhoods in the three cities and how they have changed over time, to clarify if the neighborhood-level urban form of the three cities have transformed in a similar fashion, and to address the differences between the cities. The variables of this study were population density, centrality, formation and location of facilities, and configuration of street networks, which were tested by T and Chi-square methods in a representative sample of 259 neighborhoods randomly selected from the case-study cities. The results of statistical hypothesis testing reveal a similarity of neighborhood transformations in the cities in terms of population density. Considerable similarities were found in case of historical changes in centrality (the centeredness of neighborhood amenities), location of neighborhood facilities, and street networks; however, the three cities have general similarities in trends, with potentially similar results for urban mobility. The most important identified planning, political, and societal trends that transformed the neighborhood morphologies were top-down interventions in the 1930s and 1940s, socioeconomic and lifestyle changes in the 1970s because of a jump in oil prices, Iran's 1979 revolution, the Iran-Iraq War for Tehran, internal migration triggered by industrialization, mass and formal housing production for Istanbul, and European inspiration in urban planning in the late 19th century, adoption of socialist ideologies in the 1960s, and the capitalist approach to urban planning in recent years for Cairo. 相似文献
89.
90.
长距离输水隧洞等线路工程建设将不可避免地穿越活动断裂带,引发隧洞结构变形失稳风险。可靠的结构安全监测方案是有效监控隧洞结构安全状态、评价抗错断措施适应性的必要手段,目前还少有与隧洞穿越活动断裂带结构安全监测体系相关的研究。针对该问题,提出了过活动断裂带隧洞结构安全监测的“五适应”设置原则,即:与现行规范或技术标准相适应、与活动断裂带活动特征相适应、与隧洞结构变形规律和破坏特征相适应、与抗断措施相适应、与隧洞开挖施工方法相适应。然后,以滇中引水工程香炉山隧洞为对象,根据断裂带蠕滑作用下的隧洞结构变形破坏规律,开展了基于“五适应”设置原则的安全监测体系和布置设计研究。研究认为香炉山隧洞在穿越丽江-剑川断裂时,应以围岩变形、接缝开合度等为主要监测项目,以接缝剪切压缩量和混凝土压应变等为基本监测内容,以影响带-主断带的交汇区域为重点关注区域,以位错计、错缝计、应变计和压力计为监测仪器,并明确了与监测对象同步实施的布置时机。由此建立隧洞穿越活动断裂带的结构安全监测体系,为隧洞过活动断裂带的安全监测布置设计提供了有益的思路。 相似文献