This article summarises some considerations surrounding a geoid-model-based vertical datum that have to be thought through before its implementation and adoption. Our examples are based on many Australian and some South-East Asian experiences, but these probably also apply elsewhere. Thekey considerations comprisedataquality andavailability, politics, anddifficulties thatusersmayencounterwhen a...

Seamless integration of land-elevation and water-depth information in coastal environments is required in many geospatial applications and decision-making processes. Vertical datum conversion is the central component of the integration process. This study introduces a methodology of vertical datum conversion in Lake Erie, which utilizes the public published models and toolkits developed by Nati...

We present experimentally-acquired MR image sequence reconstruction results and a review of the recently proposed doubly adaptive temporal update method (DATUM) for the acquisition of dynamic MRI sequences. The DATUM algorithm is novel in providing an estimation and tracking framework for both image reconstruction and the image acquisition inputs. We discuss the difficulty in choosing viable sy...

A non-resonant microwave method has been proposed for accurate complex permittivity determination of low-loss materials. The method uses two measurement data of the magnitude of transmission properties of the sample. While the first datum must correspond to a frequency point resulting in a maximum magnitude of transmission properties, the other can be any datum at a frequency different than the...

In support of the National Oceanic and Atmospheric Administration’s VDatum program, a new version of a tidal datum product for the North Carolina coastal waters has been developed to replace the initial version released in 2004. Compared with the initial version, the new version used a higher resolution grid to cover more areas and incorporated up-to-date tide, bathymetry, and shoreline data. P...

The rapid proliferation of coordinate measuring machines (CMMs) triggered the need for precise and rigorous formulations of each tolerance concept. In this paper, we employ the concept of con guration space of symmetric features to de ne each type of datum features and orientation tolerances. The establishment of datum features and orientation tolerances are formulated in an linear programming ...

Any measurement task requires a fixed reference base (the datum’) from which measurements can be made and calculated. The linac was the datum to which all SLC components were aligned; although this reference existed as a physical object, the actual establishment of the datum and its transferral to datums that were more useful for the SLC installation challenged the technology and computational ...

David Vogan gave programmatic conjectures about the Dixmier's map and he made two conjectures that induction may be independent of the choice of parabolic group used and the sheets of orbit data are conjugated or disjointed. In our previous paper, we gave a geometric version of the parabolic induction of the geometric orbit datum (i.e. orbit covers), and proved Vogan's rst conjecture for geomet...

This paper proposes a scheme for the tolerance specification that uses the features’ function information and mating condition attributes in the assembly to derive an appropriate tolerance specification as per the design intents. The proposed mirror method provides a way to locate the critical components. It helps the user identify functional features and group them into clusters. Temporary DRF...