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361.
This paper considers issues of authenticity as they apply to the evolution of farmers' markets in New Zealand. Following a discussion of the nature of authenticity and its deployment by farmers' market organisations in several jurisdictions, a two‐part case study is presented. An analysis of the strategies adopted by Farmers' Markets New Zealand to ‘protect its brand’ nationally and an examination of the disputation of authenticity in the Marlborough Farmers' Market reveals the potential of the ‘authenticity project’ to be a lightning rod for heightened tension and the fracturing of the relationship between competing interests in New Zealand farmers' markets. 相似文献
362.
Trisalyn A. Nelson 《The Professional geographer》2013,65(1):83-94
With many leading spatial analysts nearing retirement, reflection on the discipline becomes beneficial. To capture some of their collective perspective, fifty-eight researchers were surveyed on key spatial analysis developments, future challenges, and essential readings for newcomers. Geographic information systems (GIS), new data sources, improved understanding of spatial autocorrelation, spatially local methods, and the spread of spatial analysis beyond geography featured prominently among the twenty-four respondents. Future challenges included overcoming methodological limitations and retaining spatial analysis within geography. Twelve books highlighted by respondents are also summarized. Finally, a synthesis and some thoughts based on survey results are presented. 相似文献
363.
Jennifer L. Rice 《The Professional geographer》2013,65(2):333-344
A survey of local governments participating in two urban climate change programs is presented to determine the mechanisms used to reach emissions reduction goals and the motivations for participation. Results support previous research that shows a preference for policies that rely on changes in individual behavior, while also providing new insights into how mitigation responsibilities are distributed among the public and private sector and the relative importance of scientific consensus, economic incentives, and federal inaction on local government justification for climate-related policies. The article concludes with a discussion of urban climate governance as part of a wider system of neoliberal climate governance. 相似文献
364.
In this article, we use local indicators of spatial association (LISA) and other spatial analysis techniques to analyze the distribution of centers with high employment density within metropolitan areas. We examine the 359 metropolitan areas across the United States at three points in time (1990, 2000, and 2010) to provide a spatio-temporal panoramic of urban spatial structure. Our analysis highlights three key findings. (1) The monocentric structure persists in a majority of metropolitan areas: 56.5% in 1990, 64.1% in 2000, and 57.7% in 2010. (2) The pattern of employment centers remains stable for most metropolitan areas: the number of centers remained the same for 74.9% of metropolitan areas between 1990 and 2000 and for 85.2% between 2000 and 2010. (3) Compared with monocentric metropolitan areas, polycentric metros are larger and more dense, with higher per-capita incomes and lower poverty rates. 相似文献
365.
Thomas J. Cooke 《Urban geography》2013,34(2):219-235
The human capital and creative class hypotheses argue that the agglomeration of skilled and creative people is key to economic growth. Migration is assumed to play an important role in forming these agglomerations. However, the results of this study indicate that while younger cohorts of skilled and creative individuals are highly mobile, skilled and creative couples are highly immobile. This research hypothesizes that it is these relatively immobile skilled and creative couples that are behind the link between urban growth and concentrations of skill and creativity. Indeed, this analysis finds a strong empirical link between concentrations of skilled couples, but not creative class couples, and economic growth. Public policies designed to increase the size of the skilled population should be directed at retaining younger cohorts long enough for them to develop the local networks upon which spillover effects rely. 相似文献
366.
地方城市的人口回流与移民战略——基于深圳-驻马店的调查研究 总被引:3,自引:2,他引:1
改革开放30 多年来,沿海大都市和内陆地方城市之间的发展差距不断拉大,其中人口流动是重要动因。因此,如何吸引人口回流,留住本地人才,是内陆地方城市未来发展的关键。在此背景下,以驻马店为案例地,通过实地调研和问卷访谈,探讨了在深圳市的驻马店籍人口的回流意愿,以及当前驻马店的人口回流状况,并重点对回流创业者与回流购房者的回流动因、地域选择、就业动向及预期等进行了调查分析。研究表明,以驻马店为代表的地方城市已出现了以U-turn 与I-turn 为主的人口回流现象,且回流人口大都从事或打算从事与之前就业行业相关的创业活动。已发现有两种主动回流类型,即创业回流和购房回流。其中,购房回流也可看作是创业回流的前奏,二者可理解为同一回流过程的两个阶段。如果地方政府能够做出积极的政策引导,回流人口及其带动的返乡经济可望成为地方城市摆脱发展困境的一个新战略。 相似文献
367.
Sediment fingerprinting in fluvial systems: review of tracers,sediment sources and mixing models 总被引:3,自引:0,他引:3
Suspended sediments in fluvial systems originate from a myriad of diffuse and point sources, with the relative contribution from each source varying over time and space. The process of sediment fingerprinting focuses on developing methods that enable discrete sediment sources to be identified from a composite sample of suspended material. This review identifies existing methodological steps for sediment fingerprinting including fluvial and source sampling, and critically compares biogeochemical and physical tracers used in fingerprinting studies. Implications of applying different mixing models to the same source data are explored using data from 41 catchments across Europe, Africa, Australia, Asia, and North and South America. The application of seven commonly used mixing models to two case studies from the US (North Fork Broad River watershed) and France (Bldone watershed) with local and global (genetic algorithm) optimization methods identified all outputs remained in the acceptable range of error defined by the original authors. We propose future sediment fingerprinting studies use models that combine the best explanatory parameters provided by the modified Collins (using correction factors) and Hughes (relying on iterations involving all data, and not only their mean values) models with optimization using genetic algorithms to best predict the relative contribution of sediment sources to fluvial systems. 相似文献
368.
王少燕 《测绘与空间地理信息》2013,36(7):130-132
随着国家电网公司空间信息服务平台的建设和2000国家大地坐标系(CGCS 2000)的启用,迫切需要将各省不同坐标系的空间数据统一转换到CGCS 2000,从而实现电网空间信息服务平台的纵向贯通及空间数据资源的整合和共享。本文根据电力GIS空间数据资源的特点及行业情况,阐述了电网GIS中现有成果从独立坐标系向CGCS 2000转换的实现,并提出了对转换成果的验证方法。 相似文献
369.
介绍了弱交汇条件下利用PixelGrid系统实现稀少控制点区域的卫星影像的)L4*--r~,t正方法。阐述了操作流程以及每个步骤的注意事项,对纠正后的影像做出精度检测并给出分析评价。 相似文献
370.
《Urban geography》2013,34(2):139-172
Although welfare rolls have dropped considerably in recent years, most welfare recipients who find work are employed in low-wage, insecure jobs. The problem of "working poverty" is especially acute in large city-regions such as Los Angeles, where local labor market restructuring has created an expanding, low-wage economy, increasingly dependent on immigrant labor. This paper analyzes the employment outcomes of 6,931 women who completed the county's welfare-to-work program in 1996. I evaluate their earnings, labor market segmentation, and job stability. The results show that women were highly concentrated in low-wage service jobs and experienced high levels of turnover and unemployment. Many were unable to obtain employment in the formal labor market. I argue that the struggles of the working poor in a growing regional economy are explained not solely by human capital limitations, but by processes of local labor market restructuring that have contributed to widespread economic insecurity in Los Angeles County. 相似文献