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For large-scale 3D building reconstruction, there have been several approaches to utilizing multi-view satellite imagery to produce a digital surface model (DSM) for height information and extracting building footprints for contour information. However, limited by satellite resolutions and viewing angles, the corresponding DSM and building footprints are sometimes of a low accuracy, thus generating low-accuracy building models. Though some recent studies have added GIS data to refine the contour of the building footprints, the registration errors between the GIS data and satellite images are not considered. Since OpenStreetMap (OSM) provides a high level of precision and complete building polygons in most cities worldwide, this paper proposes an automatic single building reconstruction method that utilizes a DSM from high-resolution satellite stereos, as well as building footprints from OSM. The core algorithm accurately registers the building polygons from OSM with the rasterized height information from the DSM. To achieve this goal, this paper proposes a two-step "coarse-to-fine registration" algorithm, with both steps being formulated into the optimization of energy functions. The coarse registration is optimized by separately moving the OSM polygons at fixed steps with the constraints of a boundary gradient, an interior elevation mean, and variance. Given the initial solution of the coarse registration, the fine registration is optimized by a genetic algorithm to compute the accurate translations and rotations between the DSM and OSM. Experiments performed in the Beijing/Shanghai region show that the proposed method can significantly improve the IoU (intersection over union) of the registration results by 69.8%/26.2%, the precision by 41.0%/15.5%, the recall by 41.0%/16.0%, and the F1-score by 42.7%/15.8%. For the registration, the method can reduce the translation errors by 4.656 m/2.815 m, as well as the rotation errors by 0.538°/0.228°, which indicates its great potential in smart 3D applications. [ABSTRACT FROM AUTHOR]

Research on the geography of metropolitan opportunities has focused on a set of opportunities in different urban areas over time to justify policy interventions. The Beijing government implemented large-scale policy interventions to achieve structural industrial changes in order to stop the downward spiral of poverty and segregation in "urban villages." Beijing has accelerated the redevelopment of urban villages and helped tens of thousands of low-wage migrant workers in garment villages move to surrounding secondary cities or small towns in Hebei Province with better opportunities. However, low-wage migrant workers did not respond linearly to the intervention. This study analyzes the reasons underlying the response of low-wage migrant workers to these policy interventions. First, the antipoverty policy is a geographic exercise, moving low-end industries from a global center to peripheral locations. This study considers why this mobility strategy for improving opportunity has become the arena for opportunistic behavior and conceptualizes the logic of opportunism and the self-worth of low-wage migrant workers in a metropolitan area. Second, the Beijing government is attempting to disperse the low-end informal industries into formal industrial bases in Hebei. Dispersal campaigns inevitably involve circuitous mobility and the outcome of dispersal is inherently unstable. One of the crucial questions in dispersal strategies is scale. Would an upscaled Beijing-Tianjin-Hebei (BTH) City Region or a downscaled "neighborhood effect" better implement the antipoverty strategy? This dispersal strategy can break up the concentration of migrants, but their perceived opportunities remain in Beijing. One of the obstacles to the full implementation of the dispersal strategy is grassroots opposition. This study uses a three-year survey conducted prior to the COVID−19 lockdown to analyze how displaced migrant workers perceive these opportunities in their processual and networked decision-making. Garment villages are important "anchor places" where migrants can mobilize their social capital and facilitate upward mobility outside a dominant institution in Beijing. This study reveals how garment workers replicated informal habitats in more remote locations in Beijing as the old habitats disappeared. • Urban villages provide a critical "anchor" for the social reproduction of migrants. • Migrants often replicate the urban village in more remote locations when the old one disappears. • Suzhi discourse is an intangible factor in labor mobility. • Migrants' networks may be diluted in the upscaled Beijing-Tianjin-Hebei regionalism. • We need more inclusive policies to settle the displaced workers. [ABSTRACT FROM AUTHOR]

Background: The incidence of Pneumocystis pneumonia (PCP) among patients without human immunodeficiency virus (HIV) infection continues to increase. Here, we identified potential risk factors for in‐hospital mortality among HIV‐negative patients with PCP admitted to the intensive care unit (ICU). Methods: We retrospectively analyzed medical records of 154 non‐HIV‐infected PCP patients admitted to the ICU at Peking Union Medical College Hospital (PUMCH) and China‐Japan Friendship Hospital (CJFH) from October 2012 to July 2020. Clinical characteristics were examined, and factors related to in‐hospital mortality were analyzed. Results: A total of 154 patients were enrolled in our study. Overall, the in‐hospital mortality rate was 65.6%. The univariate analysis indicated that nonsurvivors were older (58 vs. 52 years, P = 0.021), were more likely to use high‐dose steroids (≥1 mg/kg/day prednisone equivalent, 39.62% vs. 55.34%, P = 0.047), receive caspofungin during hospitalization (44.6% vs. 28.3%, P = 0.049), require invasive ventilation (83.2% vs. 47.2%, P < 0.001), develop shock during hospitalization (61.4% vs. 20.8%, P < 0.001), and develop pneumomediastinum (21.8% vs. 47.2%, P = 0.001) and had higher Acute Physiology and Chronic Health Evaluation (APACHE) II scores on ICU admission (20.32 vs. 17.39, P = 0.003), lower lymphocyte counts (430 vs. 570 cells/μl, P = 0.014), and lower PaO2/FiO2 values (mmHg) on admission (108 vs. 147, P = 0.001). Multivariate analysis showed that age (odds ratio [OR] 1.03; 95% confidence interval [CI] 1.00–1.06; P = 0.024), use of high‐dose steroids (≥1 mg/kg/day prednisone equivalent) during hospitalization (OR 2.29; 95% CI 1.07–4.90; P = 0.034), and a low oxygenation index on admission (OR 0.99; 95% CI 0.99–1.00; P = 0.014) were associated with in‐hospital mortality. Conclusions: The mortality rate of non‐HIV‐infected patients with PCP was high, and predictive factors of a poor prognosis were advanced age, use of high‐dose steroids (≥1 mg/kg/day prednisone equivalent) during hospitalization, and a low oxygenation index on admission. The use of caspofungin during hospitalization might have no contribution to the prognosis of non‐HIV‐infected patients with PCP in the ICU. [ABSTRACT FROM AUTHOR]