Emergency escape roof hatches are used to evacuate school buses in rolled-over orientations. In the United States, the minimum opening size of a roof hatch is defined by Federal Motor Vehicle Safety Standard (FMVSS) no. 217. With the prevalence of rising obesity rates among children, the minimum roof hatch opening size may not be large enough to accommodate larger passengers. Post-accident conditions such as injuries, disorientation, and exit obstructions may also prevent unobstructed passage for egress within acceptable time limits. The purpose of this study was to redesign and fabricate a roof hatch with a larger opening and evaluate its egress characteristics for a range of typical school bus passengers. The larger roof hatch opening allows greater evacuation flow rates, and is almost functionally equivalent to the evacuation flow rate of the front door on an upright school bus.
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http://dx.doi.org/10.1016/j.apergo.2020.103178 | DOI Listing |
Micromachines (Basel)
February 2024
Gemmological Institute, China University of Geosciences, Wuhan 430074, China.
A challenge remains in achieving adequate surface roughness of SLM fabricated interior channels, which is crucial for fuel delivery in the space industry. This study investigated the surface roughness of interior fine flow channels (1 mm diameter) embedded in SLM fabricated TC4 alloy space components. A machine learning approach identified layer thickness as a significant factor affecting interior channel surface roughness, with an importance score of 1.
View Article and Find Full Text PDFGlob Chang Biol
October 2023
Consiglio Nazionale delle Ricerche-Istituto di Ricerca sulle Acque (CNR-IRSA), Brugherio, Italy.
Future climatic scenarios forecast increases in average temperatures as well as in the frequency, duration, and intensity of extreme events, such as heatwaves. Whereas behavioral adjustments can buffer direct physiological and fitness costs of exposure to excessive temperature in wild animals, these may prove more difficult during specific life stages when vagility is reduced (e.g.
View Article and Find Full Text PDFJ Anat
October 2023
Department of Evolutionary Biology and Conservation of Vertebrates, Faculty of Biological Sciences, University of Wrocław, Wrocław, Poland.
Gekkotans are one of the major clades of squamate reptiles. As one of the earliest-diverging lineages, they are crucial in studying deep-level squamate phylogeny and evolution. Developmental studies can shed light on the origin of many important morphological characters, yet our knowledge of cranial development in gekkotans is very incomplete.
View Article and Find Full Text PDFAnat Rec (Hoboken)
October 2022
Museum of Comparative Zoology and Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA.
Anat Rec (Hoboken)
December 2021
Department of Earth Sciences, Carleton University, Ottawa, Ontario, Canada.
Embryonic staging tables provide a standard of developmental stages that can be used by individual investigators and provide approximate time points for the study of developmental phenomena. Surprisingly, despite the presence of a plethora of studies on the chicken skull and its role as a model species in developmental research, a staging table of the development of the chicken skull remains lacking. A detailed photographic staging table of the osseous portion of the chicken skull is thus presented here based on cleared and stained HH stages spanning HH 35 (first appearance of skull ossification) to the final stage before hatching (HH 45).
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