Deflection behavior of sandwich panel with corrugated core of trapezoidal cross section

The Low Impact Development (LID) Control module is utilized in the United States Environmental Protection Agency’s Stormwater Management Model (USEPA SWMM) to predict the hydraulic performance of a variety of sustainable stormwater technologies. Data collected in 2019 from the monitoring of a pilot project in Montreal was used to verify the ability of the Bioretention LID Control (which assumes a rectangular cross-section) to accurately simulate outflow from a structure with a trapezoidal cross-section. Two types of LID facility were modeled: one releases captured inflow through a perforated underdrain below the soil layer (bioretention basin; BB); and the other is drained at the surface of the soil layer (vegetated swale; VS). Initially, the modeled LID structures were sized identically to the field surface areas. However, it was necessary to change their model representation to account for the non-rectangular shape of the soil layer. In addition, a sensitivity analysis was completed, and the most influential parameters were identified as the conductivity slope and seepage rate. Both the alteration of the LID structure representation and the parametric calibration greatly improved the simulated outflows from the vegetated swale resulting in an increase of the Nash–Sutcliffe efficiency (NSE) coefficient from −0.6 to 0.64 (NSE >0.5 is acceptable for hydrologic models according to the literature). The bioretention basin calibration did not prove as successful. The evaluated LID Control module presented better predictive capabilities for the basin with a simpler overall design (VS).

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Nanobiotechnology: Biological Applications of Nanofabrication

Microscopy and Microanalysis ◽

10.1017/s1431927600024570 ◽

1998 ◽

Vol 4 (S2) ◽

pp. 890-891

Author(s):

J.N. Turner ◽

W. Shain ◽

D.H. Szarowski ◽

L. Kam ◽

H.C. Craighead ◽

...

Keyword(s):

Surface Modification ◽

Glial Fibrillary Acidic Protein ◽

Cross Section ◽

Confocal Microscope ◽

Reactive Astrocytes ◽

Biological Applications ◽

Cross Sectional ◽

Trapezoidal Cross Section ◽

Brain Physiology ◽

Biological Studies

Nanobiotechnology is the fusion of biology and nanofabrication (Hoch, et al. 1996). Nanofabricated devices are increasingly being used in biological studies, and surface modification methods are important for interfacing inorganic devices with tissues.Nanofabricated implants are used to study brain physiology (Najafi and Wise, 1986). These implants can have cross-sectional dimensions as small as 15 μm. However, the implants cause glial scars that inhibit their operation. Figure 1 shows a model implant, with a trapezoidal cross section (base=200 μm, height=130 μm, top=60 μm, length=2 mm), for studying scar formation. Implants were inserted into the brains of rats and tissue was harvested after 1 hr. to 12 wks. Figure 2 shows a thick (100 μm) section of brain prepared 7 days after implantation; the section was immunolabeled for glial fibrillary acidic protein (GFAP) and imaged in a Bio-Rad confocal microscope. The implantation site is surrounded by GFAP positive material indicative of reactive astrocytes.

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