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Boulder, CO, United States

Mitchell D.L.,Desert Research Institute | Mishra S.,Desert Research Institute | Lawson R.P.,SPEC, Inc.
Journal of Geophysical Research: Atmospheres | Year: 2011

Ice fall velocity has a strong impact on climate feedback, influencing cirrus cloud coverage and radiative forcing as well as upper troposphere relative humidity. This study aims to provide the atmospheric modeling community with better parameterizations of the ice fall speed in cirrus clouds on the basis of aircraft measurements from recent field campaigns, especially the Tropical Composition, Cloud and Climate Coupling (TC4) campaign in 2007 and the Indirect and Semi-Direct Aerosol Campaign (ISDAC) in 2008. These campaigns provide improved measurements of the ice particle size distribution (PSD) where the concentrations of artifact small ice particles (due to shattering of ice particles on the probe inlet tube) are greatly reduced. In addition to the PSD, the mass-weighted fall velocity (Vm) depends on the ice particle projected area and mass. The calculation of Vm was based on improved direct measurements of the PSD number and area concentration and improved estimates of ice particle mass. The effective diameter (De) was calculated in a similar way. The TC4 analysis has provided a diagnostic relationship that relates Vm to both cloud temperature (T) and ice water content (IWC) with an r2 of 0.78. A similar relationship for De was also obtained with an r2 of 0.82. The Vm relationship and associated Vm-IWC-T measurements were found to agree well with a Vm scheme based on T and cloud radar retrievals of Vm and IWC in tropical cirrus clouds. However, a critical climate-influencing parameter like the ice fall speed needs to be coupled with the cloud microphysics and radiation in climate models. This is made possible through strong correlations between De and Vm regarding TC4 and ISDAC cirrus. Finally, TC4 satellite retrievals of De and Vm are found to be consistent with corresponding observations. Copyright 2011 by the American Geophysical Union. Source

SPEC, Inc. | Date: 2015-12-14

A fixing device includes an encircle element having lateral sides and left and right flap portions located inwardly of the lateral sides and extending transversely and outwardly from the lateral sides to define left and right chambers which are accessible only from the same direction, each of the left and right lateral sides being formed with a through hole; a fixing element installed on the encircle element at one of the through holes; and a locking plate having a first end fastened movably to the encircle element via a fastener such that the locking plate is movable relative to the encircle element between a locked position, where a second end of the locking plate engages the fixing elements, thereby preventing access into the chambers, and an unlocked position, where the locking plate disengages the fixing elements, thereby permitting access into the chambers.

SPEC, Inc. | Date: 2015-06-18

A structurally supportive backer panel formed to fit within the recesses of a form liner to support the form liner when casting textured surfaces into concrete. The backer panel has a series of protrusions which fit within the recesses of the form liner in order to prevent the concrete pressure from deflecting and buckling the form liner. When the wet concrete is poured into a form fitted with the backer panel and form liner, the concrete fills the form and contacts the form liner, wherein the backer panel ensures that the shape of the form liner is not affected by the pressure and weight of the concrete.

SPEC, Inc. | Date: 2011-03-29

A canopy apparatus includes a first and a second track assembly, a first and a second slide member, a frame apparatus, and a canopy assembly. The first and the second track assembly are configured for connection to the vehicle, the first track assembly defines a longitudinal axis. The first slide member slideably engages the first track assembly and is configured to move relative to the first track assembly in a direction parallel to the longitudinal axis. The second slide member slideably engages the second track assembly and is configured to move relative to the second track assembly in the direction parallel to the longitudinal axis. The frame apparatus includes a bail member having a first end portion configured for pivotal connection to the first slide member and a second end portion configured for pivotal connection to the second slide member. The canopy assembly is configured for connection to the frame apparatus. The frame apparatus is configured for movement in the direction parallel to the longitudinal axis about the first and the second track assemblies.

SPEC, Inc. | Date: 2010-04-15

An adaptor for a power drill includes an offset drive and means to adjust the rotated position of said offset drive with respect to the chuck of the drill.

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