One of the important parameters used in optics is the refractive index. There are different methods to measure the refractive index in the visible region. One of the techniques used to carry out these measurements uses the method of minimum deviation that suffers a ray of light when crossing a prism. Other common methods are based on the determination of the critical angle and in the Brewster a...

objective: this study was designed to compare the stress produced at the pdl of abutment teeth with two angles of cervical convergence, in otherwise similar settings. materials and methods: two finite element models were designed for a second premolar and a removable partial denture frame containing an i-bar clasp. maximum principal stress (s1) and von mises stress (seqv) were assessed along a ...

a finite element analysis is presented for sloshing and impulsive motion of liquid-filled conical tanks during lateral anti-symmetric excitation. the performed analyses led to the development of a number of charts which can be used to identify the natural frequency, the mode shapes of conical tanks for both fundamental and the cos(θ)-modes of vibration. conical tank geometry was described with ...

In the title chiral aldimine, C(19)H(17)N, the azomethine group is not fully conjugated with the phenyl substituent: the dihedral angle between phenyl and C(*)-N=C mean planes is ϕ(3) = 23.0 (2)°. Compared with the earlier DFT-B3LYP/6-31 G(d) computations from the literature, the C=N-C(*)-C(naph-thyl) torsion angle, found at ϕ(2) = -118.0 (2)° in the X-ray structure, does not match the angle ca...

The purpose of the present study was to establish a geometric design method for class I inlay cavities as a future method of computer-aided tooth preparation. Major occlusal fissures were used as a starting point of the cavity design and marked as multiple continuous line segments. An experimental cavity outline was defined by circular arcs and Bézier curves with three design parameters: minimu...

Title of Thesis: FASTER DISPLAY OF MECHANICAL ASSEMBLIES BY DETERMINATION OF PART VISIBILITY Jeremy Ou, Master of Science, 2004 Thesis directed by: Professor Edward B. Magrab. Department of Mechanical Engineering We present algorithms that greatly decrease the time it takes to display a large number of 3-D mechanical part assemblies by removing all interior parts that cannot be viewed from any ...

there are limitations in experimental studies on sand-gravel mixtures due to the small size of testingspecimens. due to this problem, many researchers have worked on prediction of the shear strength of mixture by testingthe sandy fraction of soil alone and developed empirical relationships. most of the previous relationships have beendetermined for low surcharge pressures in which particle brea...

Abstract: This paper proposes a novel protection method for single line-to-ground (SLG) faults in ungrounded low-inertia microgrids. The proposed method includes microgrid interface protection and unit protection. The microgrid interface protection is based on the difference between the zero-sequence voltage angle and the zero-sequence current angle at the microgrid interconnection transformer ...

Splines with free knots have been extensively studied in regard to calculating the optimal knot positions. The dependence of the accuracy of approximation on the knot distribution is highly nonlinear, and optimisation techniques face a difficult problem of multiple local minima. The domain of the problem is a simplex, which adds to the complexity. We have applied a recently developed cutting an...

the cracked brazilian disc (cbd) specimen is widely used in order to determine mode-i/ii and mixed-mode fracture toughness of a rock medium. in this study, the stress intensity factor (sif) on the crack-tip in this specimen is calculated for various geometrical crack conditions using the extended-finite element method (x-fem). this method is based upon the finite element method (fem). in this m...