On the Design of the Amoeba Configuration Manager

The program Amoeba Make, or Amake, is being designed to fulfil the need of a make-like configuration manager capable of exploiting the potentials of the Amoeba distributed operating system. The major design goal is to create a software configuration manager that is both easy to use and efficient. The specification and maintenance of a large configuration should be easy, and should be automated as much as possible. Furthermore, the build process should exploit Amoeba's capabilities and resources when creating or updating a target. In this paper we show how a smart file server can contribute to Amake's efficiency. We also show how a declarative configuration description allows Amake to take full advantage of parallelism and to determine the commands needed for building and maintaining targets

Collaborative Aircraft Design Methodology using ADAS linked to CEASIOM

The aircraft design stages, conceptual and preliminary, are necessarily collaborative bytheir very nature. An example design carried out in this paper brings the collaborativeaspects of design to life by two academic groups, one in Naples and one in Stockholm, usingtheir own tools ADAS and CEASIOM, working respectively on conceptual and preliminarydesign. The ADAS tool is primarily empirically-based design methodology, and the CEA-SIOM tool is primarily physics-based design methodology. The example chosen is a FAR-23compliant 16-seat twin turboprop aircraft. The high-wing configuration resulting from theADAS conceptual design is the down-selected to CEASIOM where a water-tight model of thegeometry is constructed, a volume grid is generated and 16 flight conditions are simulatedby solutions of the Euler equations, some with propeller off, and others with propellerin order to judge the effect of the propeller wash over the main wing and horizontal tailsurface. Detailed comparisons between ADAS results and CEASIOM results for stability &amp;control characteristics are carried out. In general there is reasonable agreement betweenthe two sets, considering that the empiricisms in ADAS account for viscous effects where asthe CEASIOM are purely inviscid (but nonlinear). The largest discrepancy appears in thepitching moment contribution from the horizontal tail, and various explanations for thisare suggested, including possible effects of the main wing downwash and wake on the tail.QC 20150527</p