3 research outputs found

    Automatic Main Road Extraction from High Resolution Satellite Imagery

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    Road information is essential for automatic GIS (geographical information system) data acquisition, transportation and urban planning. Automatic road (network) detection from high resolution satellite imagery will hold great potential for significant reduction of database development/updating cost and turnaround time. From so called low level feature detection to high level context supported grouping, so many algorithms and methodologies have been presented for this purpose. There is not any practical system that can fully automatically extract road network from space imagery for the purpose of automatic mapping. This paper presents the methodology of automatic main road detection from high resolution satellite IKONOS imagery. The strategies include multiresolution or image pyramid method, Gaussian blurring and the line finder using 1-dimemsional template correlation filter, line segment grouping and multi-layer result integration. Multi-layer or multi-resolution method for road extraction is a very effective strategy to save processing time and improve robustness. To realize the strategy, the original IKONOS image is compressed into different corresponding image resolution so that an image pyramid is generated; after that the line finder of 1-dimemsional template correlation filter after Gaussian blurring filtering is applied to detect the road centerline. Extracted centerline segments belong to or do not belong to roads. There are two ways to identify the attributes of the segments, the one is using segment grouping to form longer line segments and assign a possibility to the segment depending on the length and other geometric and photometric attribute of the segment, for example the longer segment means bigger possibility of being road. Perceptual-grouping based method is used for road segment linking by a possibility model that takes multi-information into account; here the clues existing in the gaps are considered. Another way to identify the segments is feature detection back-to-higher resolution layer from the image pyramid

    Child neurodevelopment after multidomain interventions from preconception through early childhood

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    ImportanceMultidomain interventions in pregnancy and early childhood have improved child neurodevelopment, but little is known about the effects of additional preconception interventions.ObjectiveTo evaluate the effect of a multifaceted approach including health; nutrition; water, sanitation, and hygiene (WASH); and psychosocial support interventions delivered during the preconception period and/or during pregnancy and early childhood on child neurodevelopment.Design, Setting, and ParticipantsIn this randomized trial involving low- and middle-income neighborhoods in Delhi, India, 13 500 participants were assigned to preconception interventions or routine care for the primary outcome of preterm births and childhood growth. Participants who became pregnant were randomized to pregnancy and early childhood interventions or routine care. Neurodevelopmental assessments, the trial’s secondary outcome reported herein, were conducted in a subsample of children at age 24 months, including 509 with preconception, pregnancy, and early childhood interventions; 473 with preconception interventions alone; 380 with pregnancy and early childhood interventions alone; and 350 with routine care. This study was conducted from November 1, 2020, through February 25, 2022.InterventionsHealth, nutrition, psychosocial care and support, and WASH interventions delivered during preconception, pregnancy, and early childhood periods.Main Outcomes and MeasuresCognitive, motor, language, and socioemotional performance at age 24 months, assessed using the Bayley Scales of Infant and Toddler Development 3 tool.ResultsThe mean age of participants at enrollment was 23.8 years (SD, 3.0 years). Compared with the controls at age 24 months, children in the preconception intervention groups had higher cognitive scores (mean difference [MD], 1.16; 98.3% CI, 0.18-2.13) but had similar language, motor, and socioemotional scores as controls. Those receiving pregnancy and early childhood interventions had higher cognitive (MD, 1.48; 98.3% CI, 0.49-2.46), language (MD, 2.29; 98.3% CI, 1.07-3.50), motor (MD, 1.53; 98.3% CI, 0.65-2.42), and socioemotional scores (MD, 4.15; 98.3% CI, 2.18-6.13) than did controls. The pregnancy and early childhood group also had lower incidence rate ratios (RRs) of moderate to severe delay in cognitive (incidence RR, 0.62; 98.3% CI, 0.40-0.96), language (incidence RR, 0.73; 98.3% CI, 0.57-0.93), and socioemotional (incidence RR, 0.49; 98.3% CI, 0.24-0.97) development than did those in the control group. Children in the preconception, pregnancy, and early childhood intervention group had higher cognitive (MD, 2.60; 98.3% CI, 1.08-4.12), language (MD, 3.46; 98.3% CI, 1.65-5.27), motor (MD, 2.31; 98.3% CI, 0.93-3.69), and socioemotional (MD, 5.55; 98.3% CI, 2.66-8.43) scores than did those in the control group.Conclusions and RelevanceMultidomain interventions during preconception, pregnancy and early childhood led to modest improvements in child neurodevelopment at 24 months. Such interventions for enhancing children’s development warrant further evaluation
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