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Physical Sciences and Mathematics Commons™
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Articles 1 - 4 of 4
Full-Text Articles in Physical Sciences and Mathematics
Comparing Sanitation Delivery Modalities In Urban Informal Settlement Schools: A Randomized Trial In Nairobi, Kenya, Kate Bohnert, Anna N. Chard, Alex Mwaki, Amy E., Kirby, Richard Muga, Corey L. Nagel, Evan A. Thomas, Matthew C. Freeman
Comparing Sanitation Delivery Modalities In Urban Informal Settlement Schools: A Randomized Trial In Nairobi, Kenya, Kate Bohnert, Anna N. Chard, Alex Mwaki, Amy E., Kirby, Richard Muga, Corey L. Nagel, Evan A. Thomas, Matthew C. Freeman
Mechanical and Materials Engineering Faculty Publications and Presentations
The provision of safely managed sanitation in informal settlements is a challenge, especially in schools that require durable, clean, sex-segregated facilities for a large number of children. In informal settlements in Nairobi, school sanitation facilities demand considerable capital costs, yet are prone to breakage and often unhygienic. The private sector may be able to provide quality facilities and services to schools at lower costs as an alternative to the sanitation that is traditionally provided by the government. We conducted a randomized trial comparing private sector service delivery (PSSD) of urine-diverting dry latrines with routine waste collection and maintenance and government …
Puddle Jumping: Spontaneous Ejection Of Large Liquid Droplets From Hydrophobic Surfaces During Drop Tower Tests, Babek Attari, Mark M. Weislogel, Andrew Paul Wollman, Yongkang Chen, Trevor Snyder
Puddle Jumping: Spontaneous Ejection Of Large Liquid Droplets From Hydrophobic Surfaces During Drop Tower Tests, Babek Attari, Mark M. Weislogel, Andrew Paul Wollman, Yongkang Chen, Trevor Snyder
Mechanical and Materials Engineering Faculty Publications and Presentations
Large droplets and puddles jump spontaneously from sufficiently hydrophobicsurfaces during routine drop tower tests. The simple low-cost passive mechanism can in turn be used as an experimental device to investigate dynamic droplet phenomena for drops up to 104 times larger than their normal terrestrial counterparts. We provide and/or confirm quick and qualitative design guides for such “drop shooters” as employed in drop tower tests including relationships to predict droplet ejection durations and velocities as functions of drop volume, surface texture, surface contour, wettability pattern, and fluid properties including contact angle. The latter is determined via profile image comparisons with numerical …
More Investigations In Capillary Fluidics Using A Drop Tower, Andrew Paul Wollman, Mark M. Weislogel, Brentley M. Wiles, Donald Pettit, Trevor Snyder
More Investigations In Capillary Fluidics Using A Drop Tower, Andrew Paul Wollman, Mark M. Weislogel, Brentley M. Wiles, Donald Pettit, Trevor Snyder
Mechanical and Materials Engineering Faculty Publications and Presentations
A variety of contemplative demonstrations concerning intermediate-to-large length scale capillary fluidic phenomena were made possible by the brief weightless environment of a drop tower (Wollman and Weislogel in Exp Fluids 54(4):1, 2013). In that work, capillarity-driven flows leading to unique spontaneous droplet ejections, bubble ingestions, and multiphase flows were introduced and discussed. Such efforts are continued herein. The spontaneous droplet ejection phenomena (auto-ejection) is reviewed and demonstrated on earth as well as aboard the International Space Station. This technique is then applied to novel low-g droplet combustion where soot tube structures are created in the wakes of burning drops. …
Micrometeorological Simulations To Predict The Impacts Of Heat Mitigation Strategies On Pedestrian Thermal Comfort In A Los Angeles Neighborhood, Mohammad Taleghani, David J. Sailor, George A. Ban-Weiss
Micrometeorological Simulations To Predict The Impacts Of Heat Mitigation Strategies On Pedestrian Thermal Comfort In A Los Angeles Neighborhood, Mohammad Taleghani, David J. Sailor, George A. Ban-Weiss
Mechanical and Materials Engineering Faculty Publications and Presentations
The urban heat island impacts the thermal comfort of pedestrians in cities. In this paper, the effects of four heat mitigation strategies on micrometeorology and the thermal comfort of pedestrians were simulated for a neighborhood in eastern Los Angeles County. The strategies investigated include solar reflective ‘cool roofs’, vegetative ‘green roofs’, solar reflective ‘cool pavements’, and increased streetlevel trees. Aseries of micrometeorological simulations for an extreme heat day were carried out assuming widespread adoption of each mitigation strategy. Comparing each simulation to the control simulation assuming current land cover for the neighborhood showed that additional street-trees and cool pavements reduced …