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Abstract

This article explores Houston's two Chinatowns within the context of the city's recent urban reinvestment and revitalization initiatives. It provides a history of the Chinatowns and examines their changing condition during the years that Houston was promoting ethnic diversity and urban revival. The analysis is framed within the growth machine perspective, as initially explored in Houston by Joe Feagin, and later by Jan Lin and Igor Vojnovic. Houston's late-20th-century urban redevelopment initiatives occurred during a period in history when Houston's Chinese entrepreneurs lost their influence over the local growth machine. The eventual outcome was the erasure of Houston's downtown Chinatown and the displacement of its residents from their lucrative urban core location. The disappearance of Old Chinatown and other urban ethnic neighborhoods—including Little Saigon and Freedmen's Town—from the urban core all took place as the Houston media and public were celebrating diversity, pluralism, and ethnicity in the city.  相似文献   
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He  Lingfeng  Coggan  John  Stead  Doug  Francioni  Mirko  Eyre  Matthew 《Landslides》2022,19(2):277-295
Landslides - This paper focuses on numerical modelling and back analysis of the Hell’s Mouth landslide to provide improved understanding of the evolution of a section of the north coast of...  相似文献   
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This study evaluates the quality of GPS radio occultation (RO) atmospheric excess phase data derived with single- and double-difference processing algorithms. A spectral analysis of 1 s GPS clock estimates indicates that a sampling interval of 1 s is necessary to adequately remove the GPS clock error with single-difference processing. One week (May 2–8, 2009) of COSMIC/FORMOSAT-3 data are analyzed in a post-processed mode with four different processing strategies: (1) double-differencing with 1 s GPS ground data, (2) single-differencing with 30 s GPS clock estimates (standard COSMIC Data Analysis and Archival Center product), (3) single-differencing with 5 s GPS clocks, and (4) single-differencing with 1 s GPS clocks. Analyses of a common set of 5,596 RO profiles show that the neutral atmospheric bending angles and refractivities derived from single-difference processing with 1 s GPS clocks are the highest quality. The random noise of neutral atmospheric bending angles between 60 and 80 km heights is about 1.50e−6 rad for the single-difference cases and 1.74e−6 rad for double-differencing. An analysis of pairs of collocated soundings also shows that bending angles derived from single-differencing with 1 s GPS clocks are more consistent than with the other processing strategies. Additionally, the standard deviation of the differences between RO and high-resolution European Center for Medium range Weather Forecasting (ECMWF) refractivity profiles at 30 km height is 0.60% for single-differencing with 1 and 5 s GPS clocks, 0.68% for single-differencing with 30 s clocks, and 0.66% for double-differencing. A GPS clock-sampling interval of 1 s or less is required for single- and zero-difference processing to achieve the highest quality excess atmospheric phase data for RO applications.  相似文献   
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平场校正对获得高质量的遥感图像起着非常关键的作用。针对利用商业相机开发的传感器需要进行平场校正的问题,提出对Agriculture Camera(AgCam)传感器的平场校正方法。应用AgCam的定标实验数据分别得到传感器CCD阵列的暗电流(Dark Current),渐晕效应(Vegnitting Effect)和光电响应(Quantum Efficiency)的校正系数。AgCam的定标实验数据和实际拍摄图像处理结果表明,该方法能够有效地对AgCam的平场效应进行校正。  相似文献   
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