To facilitate the accurate exchange of geometric data between different modeling systems, the approximate conversion of high degree B-spline or procedurally defined geometries to lower degree representations is required. We briefly review the algorithms we have developed to approximate high order and procedurally defined bivariate functions with integral B-splines. We also provide a test numerical example to permit comparison with alternative methods. The approximation algorithm used in this example is based on an iterative scheme in which the approximation error is estimated by adaptive sampling and is reduced through adaptive knot addition. For the approximation of high order polynomials, the effectiveness of a global error bound using convex hulls is also illustrated.
Marine Propulsor UoF (Unit of Functionality) is a segregated part of AP 226 -- Ship Mechanical Systems -- owned by Lloyd's Registry of Shipping.
This report first describes the scope of the Marine Propulsor UoF. It then presents some typical usage scenarios of the UoF for naval and industrial applications. This report is organized as follows:
Section 2 deals with the scope of the Marine Propulsor UoF. In this section, product definition data pertaining to all types and life--cycle phases of marine propulsors and their associated components for naval and commercial ships is specified. These life--cycle phases include design, analysis, model experiments, manufacturing, inspection, installation, trials, operation, repair, replacement, and decommisioning. Product definition data necessary for the definition of marine propulsors but not defined in this AP is also presented. Items which are out of scope are also given.
Section 3 presents detailed input/output information for transfer and sharing of data among various propulsor systems for the four usage scenarios classified in section 3. These scenarios include data transfer and sharing among different working approaches and processes in the same life--cycle phase of propulsors, among different life--cycle phases of propulsors, among different propulsors, and among engine and ship hull.
MIT Ocean Engineering Design Laboratory
Copyright © 1997, Massachusetts Institute of Technology
URL: http://deslab.mit.edu/DesignLab/abstracts93.html
Revised: July 23, 1997