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Full-Text Articles in Medicine and Health Sciences
An Area Based Fan Beam Projection Model, Richard E. Steele, Jiehua Zhu
An Area Based Fan Beam Projection Model, Richard E. Steele, Jiehua Zhu
Honors College Theses
Area based projection models for computed tomography mitigate raw data errors by treating X-Rays as beams, whereas traditional line based projection models treat an X-Ray like a line, thus generating significant error. In an existing area based fan beam projection model, a rotation matrix, Q, simulates the rotation of the emitter detector pair to reduce computational load, but this introduces approximations by using an approximated rotation matrix. We eliminate approximations by deriving an exact formula for the entries of Q. Using a rotation of axes and by considering the neighboring cells' contributions to the area, the result has formulations for …
Nanoparticle Penetration Of Respirator Masks At Construction Sites, Jefferson W. Doehling
Nanoparticle Penetration Of Respirator Masks At Construction Sites, Jefferson W. Doehling
Honors College Theses
This experimental investigation studies the effectiveness of N95 respirators at blocking particles between 11.5 and 154 nm in diameter during 4 different construction activities. It is well known that large amounts of dust and debris are generated during construction activities. New research has found that significantly more nanoparticles are generated during construction activities than previously thought. Consequently, the N95 respirators commonly worn to protect against these particles are only rated to block 95% particles larger than 0.3 microns in size. In this investigation, two respirator models were tested, a NIOSH TC-84A-0007 pleated N95 respirator and a NIOSH 42CFR84 foldable N95 …