A variant of the Circle Packing Theorem states that combinatorial class any convex polyhedron contains elements, called Koebe polyhedra, midscribed to unit sphere centered at origin, and these representatives are unique up Mobius transformations sphere. Motivated by this result, various papers investigate problem centering spherical configurations under transformations. In particular, Springbor...

in the last two decades, there has been an increasing interest in structural engineering control methods. shape memory alloys and seismic isolation systems are examples of passive control systems that use of any one alone, effectively improve the seismic performance of the structure. characteristics such as large strain range without any residual deformation, high damping capacity, excellent re...

BACKGROUND AND AIM: Root canal treatment, especially in curved and constricted root canals, can be very difficult and time consuming. Several investigations have compared the reciprocating and full sequence motions in terms of shaping ability. The purpose of the present study was to compare the root canal transportation and centering ability of RECIPROC and iRace using cone-beam computed tomogr...

In this paper, I give an account, in terms of centering theory [GJW86], of some phenomena of pronominalization in Italian, in particular the use of the null or the overt pronoun in subject position. After a general introduction to the Italian pronominal system, I will review centering, and then show how the original rules given in [GJW86] have to be extended or modified. Finally, I will show th...

OBJECTIVE To assess effects of off-centering, automatic exposure control, and padding on attenuation values, noise, and radiation dose when using in-plane bismuth-based shields for CT scanning. MATERIALS AND METHODS A 30 cm anthropomorphic chest phantom was scanned on a 64-multidetector CT, with the center of the phantom aligned to the gantry isocenter. Scanning was repeated after placing a b...