The future demands of computed tomography imaging regarding the x-ray source can be summarized with higher scan power, shorter rotation times, shorter cool down times and smaller focal spots. We report on a new tube technology satisfying all these demands by making use of a novel cooling principle on one hand and of a novel beam control system on the other hand. Nowadays tubes use a rotating anode disk mainly cooled via radiation. The Straton x-ray tube is the first tube available for clinical routine utilizing convective cooling exclusively. It is demonstrated that this cooling principle makes large heat storage capacities of the anode disk obsolete. The unprecedented cooling rate of 4.8 MHU/min eliminates the need for waiting times due to anode cooling in clinical workflow. Moreover, an electronic beam deflection system for focal spot position and size control opens the door to advanced applications. The physical backgrounds are discussed and the technical realization is presented. From this discussion the superior suitability of this tube to withstand g-forces well above 20 g created by fast rotating gantries will become evident. Experience from a large clinical trial is reported and possible ways for future developments are discussed.

Abstract. Lightweight, 'agile' software development methods are not a replacement for traditional, heavyweight methods. But under certain assumptions, they are a strong alternative in many areas of software development. In this paper, we outline the differences between agile and traditional approaches of software development and examine how development tools are used in the latter. We consider experience from industrial projects as well as results found in the research community. Then we discuss the requirements which agile methods and development processes impose on development tools and show how existing tool technology can be used to build agile tools. These tools allow agile methods to evolve through suitable tool support.