Chaotic Inflationary Universe on Brane

The chaotic inflationary model of the early universe, proposed by Linde is explored in the brane world considering matter described by a minimally coupled self interacting scalar field. We obtain cosmological solutions which admit evolution of a universe either from a singularity or without a singularity. It is found that a very weakly coupled self-interacting scalar field is necessary for a quartic type potential in the brane world model compared to that necessary in general relativity. In the brane world sufficient inflation may be obtained even with an initial scalar field having value less than the Planck scale. It is found that if the universe is kinetic energy dominated to begin with, it transits to an inflationary stage subsequently.Comment: 13 pages, no fig., accepted in Physical Review

Constraining spacetime torsion with LAGEOS

We compute the corrections to the orbital Lense-Thirring effect (or frame-dragging) in the presence of spacetime torsion. We derive the equations of motion of a test body in the gravitational field of a rotating axisymmetric massive body, using the parametrized framework of Mao, Tegmark, Guth and Cabi. We calculate the secular variations of the longitudes of the node and of the pericenter. We also show how the LAser GEOdynamics Satellites (LAGEOS) can be used to constrain torsion parameters. We report the experimental constraints obtained using both the nodes and perigee measurements of the orbital Lense-Thirring effect. This makes LAGEOS and Gravity Probe B (GPB) complementary frame-dragging and torsion experiments, since they constrain three different combinations of torsion parameters

Electronic document management in construction using auto-ID

The construction process relies upon the effective management of a variety of project information including drawings, specifications, bills of quantities, and other technical data. The method of information transfer determines the ease with which information can be assimilated and used in the construction process. Despite the widespread use of computers for the generation of project information, hard copy documentation remains the primary method of information transfer within the construction industry.  Electronic Document Management (EDM) systems offer a level of control over information flow within the construction process, whether documents are in hard copy or in electronic format. However, many of the existing methods of information transfer undermine the performance of EDM systems in two respects, (1) they require the user to re-enter information to register incoming documents into a data base, (2) they cannot interpret and manipulate information contained in or supporting the document. This paper describes a method of bar coding hard copy drawings in order to electronically transfer document information from designer to contractor. This approach is designed to improve the functionality of EDM systems where hard copy documents predominate. The paper also considers the requirements for bar code application standards which would further improve the data exchange process concerning documents.