The purpose of this study was to determine the true intraocular pressure and modulus of elasticity of the human cornea in vivo. The cornea was modeled as a shell, and the equations for the deformations of a shell due to applanating and intraocular pressures were combined to model the behavior of the cornea during applanation tonometry. At certain corneal dimensions called the calibration dimensions, the applanating and intraocular pressures are considered to be equal. This relationship was used to determine the modulus of elasticity of the cornea and the relationship between the applanating and intraocular pressures. The true intraocular pressure (IOPT) was found to be related to Goldmann's applanating pressure (IOPG) as IOPT = IOPG/K, where K is a correction factor. For the calibration corneal thickness of 0.52 mm, the modulus of elasticity E in MPa of the human cornea was found to be related to the true intraocular pressure IOPT in mmHg as E = 0.02291OPT. The generalization of the Imbert-Fick law that takes into account the effect of corneal dimensions and stiffness was found to be given by IOPT = 73.5W/(K A), where W is the applanating weight in gf (gram force) and A is the applanated area in mm2. The calculated true intraocular pressure and modulus of elasticity were found to agree with published experimental results. The mathematical model developed may therefore be used to improve results from applanation tonometry and to estimate the mechanical property of the cornea in vivo.

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In contact lens manufacturing, the collet chuck is one of the most common methods of holding a lens blank in a lathe in order to cut a back optic zone. In this method the lens blank is compressed by a colleting force, and the effects of this force on the back optic zone radius of the lens blank are not well known. If these effects are known, improved back optic zone radius dimensions may be obtained. In this paper, the finite element and experimental results obtained for the effects of colleting on the back optic zone radius are presented and discussed.

Equation 1 has been widely used in the scientific literature to relate GMT to climate forcing. For example, Sévellec and Drijfhout (2018) assumed "globally averaged temperature responds linearly, with some lag, to the various forcing agents." Gregory et al. (2002) reported a similar linear relationship: "General circulation models indicate that the increase in global-average outgoing radiative flux when the climate is perturbed from steady state is proportional to the global-average surface temperature change T ." Lean and Rind (2008) assumed that "surface temperatures respond linearly (at some lag) to the various influences." From data analysis of the GMT and climate forcings using the LM, they concluded that solar