A quasar superstructure

A Unified Superstructure for UML

A key aspect of successfully using UML is understanding the semantics of the notations. UML 2 will increase the already substantial collection of notations supported by UML 1.x. At the same time, this will augment the difficulty users experience in understanding semantics. In this paper we propose that while the diverse notations may render concepts differently, the concepts can often be consid...

Allophenic mice: a pillar awaiting its superstructure.

A Superstructure for Models of Quality

With additional quality modeling features added to conceptual models, computers could play a greater role in ensuring a higher level of quality in the information we model. For information-discovery applications, these additional conceptual modeling features should automatically accommodate certainty and conflicting information, support evidence-based research, automate collaboration, and provi...

Quasar Absorption Lines as a Function of Quasar Orientation Measures

We present high resolution radio data at 3.5 and 20 cm from the VLA in the A configuration for 144 quasars with known C IV absorption line properties. Using these measurements, we compare and contrast a number of quasar orientation indicators. These quantities are used to study the velocity distribution of C IV absorption lines as a function of quasar orientation measures. That there is an exce...

What Causes a Quasar ?