LOFAR, the LOw-Frequency ARray, is a new-generation radio interferometer constructed in the north of the Netherlands and across europe. Utilizing a novel phased-array design, LOFAR covers the largely unexplored low-frequency range from 10-240 MHz and provides a number of unique observing capabilities. Spreading out from a core located near the village of Exloo in the northeast of the Netherlands, a total of 40 LOFAR stations are nearing completion. A further five stations have been deployed throughout Germany, and one station has been built in each of France, Sweden, and the UK. Digital beam-forming techniques make the LOFAR system agile and allow for rapid repointing of the telescope as well as the potential for multiple simultaneous observations. With its dense core array and long interferometric baselines, LOFAR achieves unparalleled sensitivity and angular resolution in the low-frequency radio regime. The LOFAR facilities are jointly operated by the International LOFAR Telescope (ILT) foundation, as an observatory open to the global astronomical community. LOFAR is one of the first radio observatories to feature automated processing pipelines to deliver fully calibrated science products to its user community. LOFAR's new capabilities, techniques and modus operandi make it an important pathfinder for the Square Kilometre Array (SKA). We give an overview of the LOFAR instrument, its major hardware and software components, and the core science objectives that have driven its design. In addition, we present a selection of new results from the commissioning phase of this new radio observatory.

Abstract. Sharing the architectural knowledge of architectural analysis among stakeholders proves to be troublesome. This causes problems in and with architectural analysis, which can have serious consequences for the quality of a system being developed, as this quality might be incompletely or wrongly assessed. This paper presents a domain model, which can be used as a common ground among analysts and architects to capture and explicitly share such knowledge. This enables a way to overcome some of the obstacles imposed by the multi-disciplinary context in which architectural analysis takes place. To apply the domain model in practice, we have created a tool implementing (part of) this domain model for capturing and using explicit architectural knowledge during analysis. We validate the tool and domain model in the context of an industrial case study.

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