Andreas Steiner

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This document summarizes the proposals before the SQL3 committees to allow the addition of tables with valid-time and transaction-time support into SQL/Temporal, and explains how to use these facilities to migrate smoothly from a conventional relational system to one encompassing temporal support. Initially, important requirements to a temporal system that(More)
We present a temporal object data model, query language and system that support temporal database applications. We then show how equivalent temporal constructs and operations could be provided in existing object-oriented database management systems (OODBMS) and describe how we did this in the O2 system. A comparison of the two resulting systems highlights(More)
We present a temporal object model capable of representing object lifespans and also the history of their roles and associations. We adopt an approach of temporal generalisation rather than temporal extension in which a model in its entirety is given a temporal semantics through an orthogonal generalisation of all model concepts { including the lifespan of(More)
We present a general model for classiication structures that supports object role modelling. Objects can be associated with many roles simultaneously in a way that provides multiple clas-siication views over objects. Further, objects can change their roles through migration within a classiication graph. Object migration is controlled through the structure(More)
We show how model extensibility of object-oriented data management systems can be achieved through the combination of a high-level core object data model and an architecture designed with model extensibility in mind. The resulting system, OMS/Java, is both a general data management system and a framework for the development of advanced database application(More)
E-commerce technologies have reached a level of maturity where many businesses are no longer hampered by technological limitations. However, the adoption of e-commerce technologies is slower than anticipated. We argue one of the limitations is a psychological barrier, which is created by the perception that e-commerce technologies are a whole new set of(More)
OBJECTIVE A software tool is developed to facilitate data entry and to monitor research projects in under-resourced countries in real-time. METHODS The eManagement tool "odk_planner" is written in the scripting languages PHP and Python. The odk_planner is lightweight and uses minimal internet resources. It was designed to be used with the open source(More)
Optical flow sensors have been a long running theme in neuromorphic vision sensors which include circuits that implement the local background intensity adaptation mechanism seen in biological retinas. This paper reports a bio-inspired optical motion sensor aimed towards miniature robotic and aerial platforms. It combines a 20 × 20 continuous-time CMOS(More)
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