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Sager, Fritz, Christian Rosser, Céline Mavrot, und Pascal Y. Hurni (2018): A Transatlantic History of Public Administration. Analyzing the USA, Germany and France: Cheltenham: Edward Elgar. 224 Seiten. £ 75.00
Get PDFIdeengeschichtliche Abhandlungen sind in der Verwaltungswissenschaft eher selten. Dementsprechend fehlt es an einem breiten Verständnis für die intellektuellen Wurzeln des eigenen akademischen Tuns. Der hier besprochene Band von Sager und KollegInnen ist diesbezüglich eine positive Ausnahme. Die „transatlantische Geschichte“, die erzählt wird, verdeutlicht, wie reichhaltig die intellektuellen Wurzeln der modernen Verwaltungswissenschaft dies- und jenseits des Atlantiks sind. Darüber hinaus zeigt sie, wie insbesondere in der Zeit nach dem Zweiten Weltkrieg eine intensive wechselseitige Rezeption des verwaltungswissenschaftlichen Denkens zu Anpassungsprozessen und zur Modernisierung der verwaltungswissenschaftlichen Theorien, Perspektiven und Methoden geführt hat
Evaluation of fatigue strength criteria for thick-walled nodular cast iron components from EN-GJS-400 under multiaxial load
Get PDFThis paper discusses the quality of common methods for estimating the fatigue strength of EN-GJS-400-18-LT specimens under multiaxial stress. This is particularly important for the lightweight design of wind turbines. Experimental fatigue tests with axial, torsional and combined loads with a load ratio of R = -1 were performed. The results of these fatigue tests are used to validate commonly used multi-axial stress hypotheses. The investigated methods are the von Mises hypothesis, the Findley-criterion, the modified Gough-Pollard method and the critical plane nominal stress hypothesis
Die Positionen der Parteien zur Bundestagswahl 2021: Ergebnisse des Open Expert Surveys
Get PDFDiese Research Note berichtet zentrale Ergebnisse des Open Expert Surveys 2021 (OES21). In diesem Expert:innen-Survey, der vor der Bundestagswahl 2021 durchgeführt wurde, haben mehr als 300 Politikwissenschaftler:innen die wichtigsten Parteien entlang zentraler politischer Sachfragen verortet und deren Wichtigkeit für die jeweilige Partei geschätzt. Der OES21 unterscheidet sich von gängigen Expert:innenbefragungen in zweierlei Hinsicht. Zum einen umfasst der Survey zahlreiche themenspezifische Items, die in anderen Befragungen bislang keine Beachtung fanden. Zum anderen ist die Anzahl der Expert:innen sehr hoch, wodurch Zusammenhänge in der Positionierung auf Ebene der einzelnen Expert:innen analysiert werden können
Differentiability results and sensitivity calculation for optimal control of incompressible two-phase Navier-Stokes equations with surface tension
Get PDFWe analyze optimal control problems for two-phase Navier-Stokes equations with surface tension. Based on Lp-maximal regularity of the underlying linear problem and recent well-posedness results of the problem for sufficiently small data we show the differentiability of the solution with respect to initial and distributed controls for appropriate spaces resulting from the Lp-maximal regularity setting. We consider first a formulation where the interface is transformed to a hyperplane. Then we deduce differentiability results for the solution in the physical coordinates. Finally, we state an equivalent Volume-of-Fluid type formulation and use the obtained differentiability results to derive rigorosly the corresponding sensitivity equations of the Volume-of-Fluid type formulation. For objective functionals involving the velocity field or the discontinuous pressure or phase indciator field we derive differentiability results with respect to controls and state formulas for the derivative. The results of the paper form an analytical foundation for stating optimality conditions, justifying the application of derivative based optimization methods and for studying the convergence of discrete sensitivity schemes based on Volume-of-Fluid discretizations for optimal control of two-phase Navier-Stokes equations
The full story of 1000 cores : An examination of concurrency control on real(ly) large multi-socket hardware
Get PDFIn our initial DaMoN paper, we set out the goal to revisit the results of "Starring into the Abyss [...] of Concurrency Control with [1000] Cores" (Yu in Proc. VLDB Endow 8: 209-220, 2014). Against their assumption, today we do not see single-socket CPUs with 1000 cores. Instead, multi-socket hardware is prevalent today and in fact offers over 1000 cores. Hence, we evaluated concurrency control (CC) schemes on a real (Intel-based) multi-socket platform. To our surprise, we made interesting findings opposing results of the original analysis that we discussed in our initial DaMoN paper. In this paper, we further broaden our analysis, detailing the effect of hardware and workload characteristics via additional real hardware platforms (IBM Power8 and 9) and the full TPC-C transaction mix. Among others, we identified clear connections between the performance of the CC schemes and hardware characteristics, especially concerning NUMA and CPU cache. Overall, we conclude that no CC scheme can efficiently make use of large multi-socket hardware in a robust manner and suggest several directions on how CC schemes and overall OLTP DBMS should evolve in future
Unfolding and injectivity of the Kudla–Millson lift of genus 1
Get PDFWe unfold the theta integrals defining the Kudla–Millson lift of genus 1 associated to even lattices of signature (b, 2), where b > 2. This enables us to compute the Fourier expansion of such defining integrals and prove the injectivity of the Kudla–Millson lift. Although the latter result has been already proved in [5], our new procedure has the advantage of paving the ground for a strategy to prove the injectivity of the lift also for the cases of general signature and of genus greater than 1
NeRF-FF: a plug-in method to mitigate defocus blur for runtime optimized neural radiance fields
Get PDFNeural radiance fields (NeRFs) have revolutionized novel view synthesis, leading to an unprecedented level of realism in rendered images. However, the reconstruction quality of NeRFs suffers significantly from out-of-focus regions in the input images. We propose NeRF-FF, a plug-in strategy that estimates image masks based on Focus Frustums (FFs), i.e., the visible volume in the scene space that is in-focus. NeRF-FF enables a subsequently trained NeRF model to omit out-of-focus image regions during the training process. Existing methods to mitigate the effects of defocus blurred input images often leverage dynamic ray generation. This makes them incompatible with the static ray assumptions employed by runtime-performance-optimized NeRF variants, such as Instant-NGP, leading to high training times. Our experiments show that NeRF-FF outperforms state-of-the-art approaches regarding training time by two orders of magnitude—reducing it to under 1 min on end-consumer hardware—while maintaining comparable visual quality
Ab initio description of monopole resonances in light- and medium-mass nuclei : II. Ab initio PGCM calculations in ⁴⁶Ti, ²⁸Si and ²⁴Mg
Get PDFGiant resonances (GRs) are a striking manifestation of collective motions in atomic nuclei. The present paper is the second in a series of four dedicated to the use of the projected generator coordinate method (PGCM) for the ab initio determination of the isoscalar giant monopole resonance (GMR) in closed- and open-shell mid-mass nuclei. While the first paper was dedicated to quantifying various uncertainty sources, the present paper focuses on the first applications to three doubly-open shell nuclei, namely ⁴⁶Ti, ²⁸Si and ²⁴Mg. In particular, the goal is to investigate, starting from chiral effective field theory nuclear interactions, (i) the coupling of the GMR with the giant quadrupole resonance (GQR) in intrinsically-deformed nuclei, (ii) the possible impact of shape coexistence and shape mixing on the GMR, (iii) the GMR based on shape isomers and (iv) the impact of anharmonic effects on the monopole response. The latter is studied by comparing PGCM results to those obtained via the quasi-particle random phase approximation (QRPA), the traditional many-body approach to giant resonances, performed in a consistent setting. Eventually, PGCM results for sd-shell nuclei are in good agreement with experimental data, which is attributed to the capacity of the PGCM to capture the important fragmentation of the monopole response in light, intrinsically-deformed systems. Still, the comparison to data in ²⁸Si and ²⁴Mg illustrates the challenge (and the potential benefit) of extracting unambiguous experimental information
Addressing Multiple Responsibilities in the Early Stages of R&D with Provenance Assessment
Get PDFA wealth of literature and best practices on Responsible Research and Innovation (RRI) document how it can be implemented in projects. However, each project is too specific to simply replicate existing patterns. Especially in early projects with a high degree of uncertainty, where indicators and measures cannot be applied, the so-called provenance assessment as a methodological change of perspective makes it possible to assess the procedural quality of research by means of narratives. A clear picture of the challenges for European bio-economy projects is sought by mapping the broader debate on "RRI in practice" in the context of biotechnology. The SUSPHIRE project is used as a case study to show how project-specific narratives integrate and signify RRI. By unpacking various concepts of "responsibility" that are already present in the project narrative at an early stage, I will show how this assessment differs significantly from other attempts to "do RRI". It is precisely in the absence of other criteria that the assessment of provenance can bring to the fore the specific form(s) of responsibility inherent in the development of projects
Vom Verharren und Vergehen des Liberalismus
Get PDFIm Frühjahr 2023 erschienen zur selben Zeit im selben Verlag zwei Bücher zum selben Thema, die unterschiedlicher nicht sein könnten und die man unbedingt lesen sollte. Die Gießener Politikphilosophin Elif Özmen hält ein flammendes Plädoyer für eine Wiederentdeckung des klassischen Liberalismus, ohne den kein Ausweg aus dem Unheil der Gegenwart zu finden sei. Und der emeritierte US-amerikanisch-britische Cambridge-Philosoph Raymond Geuss geht in einem Rückblick auf seine Schulzeit der Frage nach, warum er nie ein Liberaler sein wollte – und warum man das auch heute besser nicht sein wollen sollte