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81.
Immigrant homeowners’ function within ethnic boundaries in the housing market may have helped or hindered them during the recent U.S. Great Recession. This research explores this theme through interviews with immigrant and non-immigrant homeowners from four ethnic communities in Los Angeles County and the non-profit organizations that tried to assist them. Immigrant homeowners turned to co-ethnics for advice and support and formed multigenerational households as a strategy to achieve and sustain homeownership. Language and cultural barriers primed them for risky loans and thwarted their pursuit of refinance and modification when they struggled to make mortgage payments. These findings conform to existing evidence of ethnic segmentation in the housing market and imply that analyses of home buying and homeownership in areas with significant immigrant populations should factor in the role of ethnicity. 相似文献
82.
83.
Daniel Toledo José Antonio Adame Benito De La Morena Manuel Gil-Ojeda 《International journal of remote sensing》2017,38(11):3203-3218
The performance of six numerical methods usually used to determine the atmospheric boundary layer (ABL) height from lidar measurements was investigated under different atmospheric conditions: results were compared with those obtained from radiosoundings to analyse their reliability for ABL-height retrievals. The selected methods were the gradient method (GM), the logarithm gradient method (LGM), the inflection point method (IPM), the wavelet covariance transform (WCT), the centroid/variance method (VM), and the cluster analysis (CA). Lidar measurements were carried out in the frame of the ‘Atmospheric Minor Species relevant to the Ozone Chemistry’ (AMISOC) project during a multi-instrument campaign conducted at the INTA/Atmospheric Observatory ‘El Arenosillo’ (INTA/ARN) in south-western Spain from 15 May to 20 June 2012. The goal of this work is to analyse the performance and robustness of the different lidar methods in this region, characterized by particular atmospheric conditions. In particular, both events of sea–land breeze regimes and episodes of Saharan dust intrusions were studied. In most days, similar results were obtained by all lidar methods in the events of sea–land breeze regimes, presenting relative absolute differences between lidar and radiosounding retrievals below 12% in average. However, big discrepancies between lidar and radiosounding retrievals are found when residual layers are present in the measurements. In such cases, the vertical extension of lidar and radiosounding profiles must to be limited to the altitude of the residual layer bottom. In a second analysis, focused on diurnal variability in the ABL heights under non-dusty (ND) and dusty (DD) conditions, the methods were tested against intensive radiosoundings launched every 4 h over 2 days. Under ND conditions, the best results were achieved for the LGM, presenting a mean of the relative absolute differences respect to radiosounding measurements of 10%. The rest of methods also provided good results with relative differences below 20% in average. Under DD conditions, however, an increase of the relative differences is found with mean values of up 32%. In this case, best results are given by CA with a mean relative difference of 20%. Despite the limited data set used in this work, results show that unlike the ND conditions for which all lidar methods provide good results respect to radiosounding retrievals, under DD conditions the election of the lidar method is a key factor for ABL estimation. However, we remark the need of extending our analysis to longer periods of time to better characterize the differences observed in this work. 相似文献
84.
Mauro F. La Russa Silvestro A. Ruffolo Natalia Rovella Cristina M. Belfiore Anna M. Palermo Maria T. Guzzi Gino M. Crisci 《Progress in Organic Coatings》2012
Environmental pollution arising from industrial implants and urban factors is constantly increasing, causing aesthetical and durability concerns to urban structures exposed to the atmosphere. 相似文献
85.
The development of Generation IV sodium-cooled fast reactors (SFR) is currently studied by several countries, France in particular. To manufacture the UO2-PuO2 fuels for these new types of reactors, new innovative wet colloidal processing routes are investigated. Among these wet colloidal processes, some involve at first the preparation of high solid content water-based suspensions. This key step needs to be investigated in order to obtain highly and easily processable suspensions, featuring optimal viscosity and dispersion state. The structures and properties for all intermediate and final products involved in such ceramic manufacturing processes are heavily affected by these suspension characteristics. Therefore, they are critical to ensure a compliant final product (i.e. fuel pellets) with the required density, homogeneity, mechanical strength and absence of defects. In this scope, preparation process of such suspensions was developed by the use of UO2 and PuO2 surrogating (i.e. mimicking) powders, TiO2 and Y2O3 respectively. 相似文献
86.
El‐Hajjaji Soundous Grard Amaury De Laubier Juliette Di Tanna Sybille Lain Aurlie Patz Viviane Sindic Marianne 《International Journal of Dairy Technology》2019,72(3):466-471
This study aims to describe the procedures and practices used in local production of raw milk butter. The demand for local products is increasing; hence, there is a need to describe the practices used in the artisanal production of raw milk butter. Therefore, a survey of 147 raw milk butter producers was carried out. The results from the survey indicate that there is not one single way to produce butter at artisanal level. In terms of maturation, six temperature sequences were distinguished. Attention is required at every step of production starting from breeding. 相似文献
87.
Daniel Ortiz Morales Simon Westerberg Pedro X. La Hera Uwe Mettin Leonid Freidovich Anton S. Shiriaev 《野外机器人技术杂志》2014,31(3):343-363
Working with forestry machines requires a great deal of training to be sufficiently skilled to operate forestry cranes. In view of this, it would be desirable within the forestry industry to introduce automated motions, such as those seen in robotic arms, to shorten the training time and make the work of the operator easier. Motivated by this fact, we have developed two experimental platforms for testing control systems and motion‐planning algorithms in real time. They correspond to a laboratory setup and a commercial version of a hydraulic manipulator used in forwarder machines. The aim of this article is to present the results of this development by providing an overview of our trajectory‐planning algorithm and motion‐control method, with a subsequent view of the experimental results. For motion control, we design feedback controllers that are able to track reference trajectories based on sensor measurements. Likewise, we provide arguments to design controllers in an open‐loop for machines that lack sensing devices. Relying on the tracking efficiency of these controllers, we design time‐efficient reference trajectories of motions that correspond to logging tasks. To demonstrate performance, we provide an overview of extensive testing done on these machines. 相似文献
88.
89.
Similarity functions are a fundamental component of many learning algorithms. When dealing with string or tree-structured data, measures based on the edit distance are widely used, and there exist a few methods for learning them from data. However, these methods offer no theoretical guarantee as to the generalization ability and discriminative power of the learned similarities. In this paper, we propose an approach to edit similarity learning based on loss minimization, called GESL. It is driven by the notion of (?,??,??)-goodness, a theory that bridges the gap between the properties of a similarity function and its performance in classification. Using the notion of uniform stability, we derive generalization guarantees that hold for a large class of loss functions. We also provide experimental results on two real-world datasets which show that edit similarities learned with GESL induce more accurate and sparser classifiers than other (standard or learned) edit similarities. 相似文献
90.
Buzzi Maria Claudia Buzzi Marina Leporini Barbara Trujillo Amaury 《Multimedia Tools and Applications》2017,76(4):5141-5169
Multimedia Tools and Applications - We present an analysis of how visually impaired people perform gestures on touch-screen smartphones and report their preferences, explaining the procedure and... 相似文献