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ABSTRACT: This research explores whether homeownership leads to increased individual social capital among low‐ to moderate‐income families. Social capital refers to social resources a person can access through contacts with others in his or her social networks. We theorize that homeownership can motivate interactions with others in one's neighborhood and therefore build social capital. Using a sample of low‐ and moderate‐income homeowners and a matched sample of renters, we collect data on overall social resources and neighborhood‐specific social resources. We find that homeowners have more total social capital resources and more neighborhood social capital resources than renters. Neighborhood group involvement has an indirect effect on social capital, but explains only a small amount of the influence of homeownership. These findings hold when controlling for household‐level and neighborhood‐level sociodemographic variables, as well as when using statistical models that account for endogeneity. Based on this evidence, we conclude that homeownership gives people access to social capital via increased social ties to others. We discuss the implications of this finding for housing policy and suggest new directions for research on social capital. 相似文献
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The use of repeater for the support of high rate data transmission and the extension of cell coverage is imperative for the Wibrc system,which based on the IEEE 8M.16e standardization.Generally,if the separation between transmitting and receiving antennas isnot sufficient,the oscillation of repeater and the interference due to the feedback signals from original transmitted signal may be ocerur.Hence,the Interference Cancellation System(ICS)should be implemented as the important part of the repeater system far the mobile cellular systems in order to eliminate unwanted signals from the corruptW signals in the receiver.In this paper,we propose an adaptive technique for the Least Mean Square(LMS)-based interference cancellation methods by changing the step size according to the variation of channel environment in order to improve the performance degradation which oceuurs by using the fixed step size approach.Simrlatim results show that the proposed sclxme attains a little lower Berafor Rate(BER)performance and much faster convergence speed compared to the conventional LMS-based interference cancellation techniques.The proposed scheme can be applied to other Orthogonal Frequency Division Multiple(OFDM)-based cellular systems and also be expected to achieve a similar performance improvement to W17-advanced system,which is called as the next generation mobile communication standards. 相似文献
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Roughness coefficient and its uncertainty in gravel-bed river 总被引:1,自引:0,他引:1
Manning's roughness coefficient was estimated for a gravel-bed river reach using field measurements of water level and discharge,and the applicability of various methods used for estimation of the roughness coefficient was evaluated.Results show that the roughness coefficient tends to decrease with increasing discharge and water depth,and over a certain range it appears to remain constant.Comparison of roughness coefficients calculated by field measurement data with those estimated by other methods shows that,although the field-measured values provide approximate roughness coefficients for relatively large discharge,there seems to be rather high uncertainty due to the difference in resultant values.For this reason,uncertainty related to the roughness coefficient was analyzed in terms of change in computed variables.On average,a 20%increase of the roughness coefficient causes a 7% increase in the water depth and an 8% decrease in velocity,but there may be about a 15% increase in the water depth and an equivalent decrease in velocity for certain cross-sections in the study reach.Finally,the validity of estimated roughness coefficient based on field measurements was examined.A 10% error in discharge measurement may lead to more than 10% uncertainty in roughness coefficient estimation,but corresponding uncertainty in computed water depth and velocity is reduced to approximately 5%.Conversely,the necessity for roughness coefficient estimation by field measurement is confirmed. 相似文献
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Design of class-based storage racks for minimizing travel time in a three-dimensional storage system
This paper deals with a new storage structure layout method called ‘cubic-in-time’, for minimizing the travel time of selected handling equipment in a three-dimensional palletized storage system. Storage-system design algorithms for minimizing travel times are described, the results are analysed, and some general conclusions are drawn. 相似文献
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