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1.
This paper asks how the livability of socially disadvantaged urban neighborhoods can be improved with the help of publicly funded area-based urban regeneration. It builds on the history of area-based regeneration policies in Germany aiming at upgrading and resolving urban problems at the neighborhood level. Its main argument is as follows. First, the fate of conventional physical upgrading policies focusing on the livability of deprived urban areas depends on the development environment. While successful upgrading sometimes makes inner-city neighborhoods so attractive that they run into a trend towards gentrification and displacement of the urban poor, the stabilization of less privileged areas cannot always be guaranteed. Second, alternative approaches are needed, linking limited physical upgrading with socially oriented policies, building on strategies like neighborhood management and empowerment. Third, they can make a substantial contribution to stabilizing deprived neighborhoods, thereby improving the general living conditions and the opportunities of the urban poor. However, they require at least some permanent intervention. Thus, they transcend the logic of area-based regeneration normally limited to restoring faith into the private real estate market and thereby directing inward investment into them that improves the quality of the physical environment. Fourth, they are hardly able to overcome significant negative stigmatization in cities that are severely hit by economic downturn and population decline. This is especially true when they act as arrival areas for consecutive waves of migrants, making it necessary to redefine the role of those areas in cities and accepting their high concentration of urban problems as a starting point for different area-based policies dealing with them. The key empirical background of the paper is the German system of urban development grants and an evaluation of the so-called program of “socially integrative city”.  相似文献   
2.
针对现有纱线毛羽检测方法无法有效检测弯曲毛羽和交叉毛羽的缺陷,提出一种基于图像法的纱线毛羽路径匹配追踪算法。将采集到的纱线毛羽图像通过预处理、骨干化处理获取毛羽骨干图像,以毛羽端点作为起始点,对其八邻域像素点进行判断获取新的毛羽路径点,重复对毛羽路径点邻域判断直到没有毛羽路径点存在。对毛羽交叉出现多路径点的情况,提出交叉匹配值指标,即根据毛羽交叉点前部分相邻毛羽路径点间斜率并分配动态权重得到毛羽局部斜度,利用交叉匹配值对多路径毛羽点进行匹配获取新的毛羽路径点,通过本文毛羽追踪方法获取毛羽像素数量并转化为毛羽长度。与人工法和投影法检测结果对比表明:本文毛羽追踪检测结果与人工检测毛羽结果误差在4%以内,有效解决了交叉毛羽和弯曲毛羽追踪检测问题,提高了纱线毛羽的检测准确度。  相似文献   
3.
We introduce a new variant of the vehicle routing problem, that is, the asymmetric multi-depot vehicle routing problem in the maintenance of farm machinery. When providing door-to-door service for farm machinery maintenance, there exists not only node service, (e.g., part replacement), but also directed arc service, (e.g., pulling the breakdown farm machinery from the farm location to the specified maintenance station). In the problem, there are multiple constraints, including the customer’s time window, maximum repairman working duration, fleet size, and vehicle capacity, etc. A mathematical programming model is formulated with the minimum total costs by transforming the problem into the asymmetric multi-depot vehicle routing problem with time windows. Discrete firefly algorithm with compound neighborhoods, presenting new neighborhood methods, is proposed to solve it. New procedures to evaluate the duration infeasibility are suggested with the reduced additional computational complexity. Computational results demonstrate that the proposed approach performs better than CPLEX solver, especially for large designed instances. Moreover, the proposed approach is superior to the other algorithms on solving benchmark instances of multi-depot vehicle routing problem with time windows. This study can provide decision support to door-to-door service for the maintenance of farm machinery.  相似文献   
4.
In this article Varady reviews his 46 years of teaching, scholarship, and service in housing policy and community development. His New York City (NY) upbringing led to interests in cities and public policy, which led to degrees in city planning and eventually to receiving his university's highest award for academic excellence. Varady's pragmatism offers realistic solutions, questions long-held attitudes, and seeks objectivity in research. Although he takes ideology seriously, he is not an ideologue. Here he explains how his pragmatic perspective affected his research on neighborhood racial change, public housing, housing vouchers, and middle income housing programs. His career is best measured by the success of his many students who have had the benefi ts of his years of experience in the fi eld of housing research in both America and Europe .  相似文献   
5.
With the advent of ‘big data’ there is an increased interest in using social media to describe city dynamics. This paper employs geo-located social media data to identify ‘digital neighborhoods’ – those areas in the city where social media is used more often. Starting with geo-located Twitter and Foursquare data for the New York City region in 2014, we applied spatial clustering techniques to detect significant groupings or ‘neighborhoods’ where social media use is high or low. The results show that beyond the business districts, digital neighborhoods occur in communities undergoing shifting socio-demographics. Neighborhoods that are not digitally oriented tend to have higher proportion of minorities and lower incomes, highlighting a social–economic divide in how social media is used in the city. Understanding the differences in these neighborhoods can help city planners interested in generating economic development proposals, civic engagement strategies, and urban design ideas that target these areas.  相似文献   
6.
Mobility, residential quality, and life outcomes are linked in the literature and these relationships have influenced low-income housing policy. This research investigates the determinants of mobility for households with a federal housing subsidy. Combining unique data from a survey of Housing Choice Voucher households, client program files, and secondary data, this study uses logistic regression to test several explanations for mobility, including the life cycle, housing market perceptions, and perceived and actual neighborhood conditions. The results indicate that a synthesis of explanations produce the best model to predict residential mobility. Neighborhood quality, perceived and actual, variables most strongly influence mobility, but life cycle factors and perception of the local housing market also impact moving choices. At the same time, the results suggest a gap in our understanding of the relationship among individuals’ environmental perceptions, formation of feelings of neighborhood satisfaction, and actual neighborhood conditions. The article concludes with a discussion of the research and policy implications from this study.  相似文献   
7.
Ryan Allen 《Housing Studies》2011,26(6):845-866
Much of the existing research on disparities in residential foreclosures provides strong, but not conclusive, evidence that minority households disproportionately experience foreclosures. Data commonly used in foreclosure research do not allow researchers to use household characteristics of foreclosed properties to test for disparities in experiencing foreclosure. This is a significant omission in the literature since understanding the types of households that most typically experience foreclosure might result in the creation of better targeted and more effective foreclosure prevention and mitigation programs. Using a unique data set this paper explores the characteristics of households that experienced a foreclosure in Minneapolis, Minnesota during fiscal years 2006 and 2007. Research results confirm that African American households disproportionately experience foreclosures, but also indicate that renter households, households with children and foreign-born homeowners are all over-represented among foreclosed households. These results have implications for how policy makers and practitioners address foreclosure prevention and mitigation efforts.  相似文献   
8.
RankVisu: Mapping from the neighborhood network   总被引:1,自引:0,他引:1  
S.  B.  P.  J. 《Neurocomputing》2009,72(13-15):2964
Most multidimensional scaling methods focus on the preservation of dissimilarities to map high dimensional items in a low-dimensional space. However, the mapping function usually does not consider the preservation of small dissimilarities as important, since the cost is small with respect to the preservation of large dissimilarities. As a consequence, an item's neighborhoods may be sacrificed for the benefit of the overall mapping. We have subsequently designed a mapping method devoted to the preservation of neighborhood ranks rather than their dissimilarities: RankVisu. A mapping of data is obtained in which neighborhood ranks are as close as possible according to the original space.A comparison with both metric and non-metric MDS highlights the pros (in particular, cluster enhancement) and cons of RankVisu.  相似文献   
9.
研究并实现基于8邻域编码逐像素跟踪法的细节特征提取算法。该算法能有效提取细化后指纹图像中的端点和分叉点,通过回朔跟踪法,能有效去除图像中的伪特征点。实验结果表明该算法较大幅度提高了特征提取的速度,并能够较准确的滤除伪特征点,缩短了图像后处理时间,可以满足实际应用的需要。  相似文献   
10.
Data from 296 sibling pairs (mean ages 10 and 13 years), their primary caregivers, and census records were used to test the hypothesis that African American children's likelihood of developing conduct problems associated with harsh parenting, a lack of nurturant-involved parenting, and exposure to an older sibling's deviance-prone attitudes and behavior would be amplified among families residing in disadvantaged neighborhoods. A latent construct representing harsh-inconsistent parenting and low levels of nurturant-involved parenting was positively associated with younger siblings' conduct disorder symptoms, as were older siblings' problematic attitudes and behavior. These associations were strongest among families residing in the most disadvantaged neighborhoods. Future research and prevention programs should focus on the specific neighborhood processes associated with increased vulnerability for behavior problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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