Search results for "Principal bundle"

Axial Load Capacity of Cold Formed Pipe Flange Connection

2017

In this paper, a cold forming process is used where the connection between a pipe and a flange is created by means of radially expanding tool segments inside the pipe. The method is investigated with two purposes, to set up a robust procedure for the process that allows for connections to be made on site, and to set up finite element (FE) simulations that can capture the forces and deformations when pulling the pipe axially out of the flange. Experimental data and FE simulations are used to describe and understand the forces and deformations during the connection process. The rapid increase in radial stiffness experienced when the pipe comes in full circumferential contact with the flange i…

Equivariant algebraic vector bundles over cones with smooth one dimensional quotient

1998

Fracture resistance after implantoplasty in three implant-abutment connection designs

2020

Background To assess the effect of implantoplasty and implant-abutment design on the fracture resistance and macroscopic morphology of narrow-diameter (3.5 mm) dental implants. Material and Methods Screw-shaped titanium dental implants (n = 48) were studied in vitro. Three groups (n = 16) were established, based on implant-abutment connection type: external hexagon, internal hexagon and conical. Eight implants from each group were subjected to an implantoplasty procedure; the remaining 8 implants served as controls. Implant wall thickness was recorded. All samples were subjected to a static strength test. Results The mean wall thickness reductions varied between 106.46 and 153.75 µm. The me…

G-Spaces and Kaluza-Klein Theory

1988

G-spaces are present whenever symmetries are relevant in physics. After a short introduction to this subject, spontaneous symmetry breaking in elementary particle physics is considered from this point of view. Kaluza-Klein theory is discussed in a purely geometrical formulation. Some results in connection with the geometrical compactification scheme are presented.

Invariants of equivariant algebraic vector bundles and inequalities for dominant weights

1998

Optimal control of the Schrödinger equation with two or three levels

2007

In this paper, we present how techniques of “control theory”, “sub-Riemannian geometry” and “singular Riemannian geometry” can be applied to some classical problems of quantum mechanics and yield improvements to some previous results.