0000000000430611
AUTHOR
A. Lorenz
showing 6 related works from this author
Need for speed? Exploring the relative importance of patents and utility models among German firms
2017
Despite the wide use of two-tiered patent systems (patents and utility models (UMs)), there is little empirical evidence about how often UMs are actually used, what kind of firms use them to protect their intellectual property, and how firms rank them relative to patents. We offer such an analysis using data from Germany. We find that larger firms are more likely to use both protection methods. Moreover, a short life cycle of products and services is associated with an increased likelihood to use UMs. The features and functioning of the German UM system are of broader interest because it has been a benchmark for several second tier patent protection systems around the world. peerReviewed
Major results from the first plasma campaign of the Wendelstein 7-X stellarator
2017
After completing the main construction phase of Wendelstein 7-X (W7-X) and successfully commissioning the device, first plasma operation started at the end of 2015. Integral commissioning of plasma start-up and operation using electron cyclotron resonance heating (ECRH) and an extensive set of plasma diagnostics have been completed, allowing initial physics studies during the first operational campaign. Both in helium and hydrogen, plasma breakdown was easily achieved. Gaining experience with plasma vessel conditioning, discharge lengths could be extended gradually. Eventually, discharges lasted up to 6 s, reaching an injected energy of 4 MJ, which is twice the limit originally agreed for t…
Overview of diagnostic performance and results for the first operation phase in Wendelstein 7-X (invited)
2016
Wendelstein 7-X, a superconducting optimized stellarator built in Greifswald/Germany, started its first plasmas with the last closed flux surface (LCFS) defined by 5 uncooled graphite limiters in December 2015. At the end of the 10 weeks long experimental campaign (OP1.1) more than 20 independent diagnostic systems were in operation, allowing detailed studies of many interesting plasma phenomena. For example, fast neutral gas manometers supported by video cameras (including one fast-frame camera with frame rates of tens of kHz) as well as visible cameras with different interference filters, with field of views covering all ten half-modules of the stellarator, discovered a MARFE-like radiati…
Overview of first Wendelstein 7-X high-performance operation
2019
Abstract The optimized superconducting stellarator device Wendelstein 7-X (with major radius , minor radius , and plasma volume) restarted operation after the assembly of a graphite heat shield and 10 inertially cooled island divertor modules. This paper reports on the results from the first high-performance plasma operation. Glow discharge conditioning and ECRH conditioning discharges in helium turned out to be important for density and edge radiation control. Plasma densities of with central electron temperatures were routinely achieved with hydrogen gas fueling, frequently terminated by a radiative collapse. In a first stage, plasma densities up to were reached with hydrogen pellet injec…
Technical challenges in the construction of the steady-state stellarator Wendelstein 7-X
2013
The next step in the Wendelstein stellarator line is the large superconducting device Wendelstein 7-X, currently under construction in Greifswald, Germany. Steady-state operation is an intrinsic feature of stellarators, and one key element of the Wendelstein 7-X mission is to demonstrate steady-state operation under plasma conditions relevant for a fusion power plant. Steady-state operation of a fusion device, on the one hand, requires the implementation of special technologies, giving rise to technical challenges during the design, fabrication and assembly of such a device. On the other hand, also the physics development of steady-state operation at high plasma performance poses a challeng…
Zwei-Ebenen-Spiele und die Asylrechtsreform von 1993
2009
Im Jahr 1993 änderten der Deutsche Bundestag und der Bundesrat das Grundgesetz (GG) und führten unter anderem eine sehr restriktive Version des Konzeptes der „sicheren Dritt- bzw. Herkunftsstaaten" ein. Dadurch wurde das in Artikel 16 (2) II garantierte Recht auf Asyl (Politisch Verfolgte genießen Asylrecht) beschränkt. Dieser Verfassungsänderung ging ein jahrelanger Streit zwischen den Parteien und zwischen Bund und Ländern voraus. Auf der einen Seite sprachen sich die von den zunehmenden Flüchtlingszahlen besonders belasteten Bundesländer seit den 1980er Jahren für eine Beschränkung des verfassungsmäßigen Asylrechts aus. Die Länder fanden Unterstützung für diese Forderung beim Bundesinnen…