Reconfiguration based built-in self-test for analogue front-end circuits

Previous work has shown that it is feasible to implement a fully digital test evaluation function to realise partial self-test on an automatic gain control circuit (AGC). This paper extends the technique to INL, DNL, offset & gain error testing of analogue to digital converters (ADC's). It also shows how the same function can be used to test an AGC / ADC pair. An extension to full self-test is also proposed by the on-chip generation of input stimuli through reconfiguration of existing functions

Institutions, corporate governance and corporate governance institutions: The case of Estonia

During the last ten years, Estonia has made strong efforts in terms of the transition to a market economy. This is particularly true with respect to the soundness and transparency of monetary and fiscal policies, the privatisation of former state-owned enterprises, the development of the financial sector and the institutional setting. This paper argues that strengthening the formal institutional setting, and in particular the corporate governance institutions, is crucial to further enhance the process of economic transition of the country. It describes the current state the corporate governance structures as compared to other countries in Central and Eastern.In den letzten 10 Jahren hat Estland viele Anstrengungen in der Umwandlung in eine Marktwirtschaft unternommen. Dies trifft insbesondere auf die Stabilität und Transparenz der Währungs- und Finanzpolitik zu, der Privatisierung ehemaliger Staatsbetriebe, die Entwicklung im Finanzsektor und im institutionellen Umfeld. Der Aufsatz zeigt auf, dass die Stärkung des formellen institutionellen Umfeldes und im einzelnen auch die der Bereiche der Unternehmensorganisation essentiell wichtig für den weiteren Tranformationsprozess des Landes sind. Er stellt den heutigen Stand der Unternehmensstrukturen im Vergleich zu anderen Staaten dar

3D Model Atmospheres for Extremely Low-Mass White Dwarfs

We present an extended grid of mean three-dimensional (3D) spectra for low-mass, pure-hydrogen atmosphere DA white dwarfs (WDs). We use CO5BOLD radiation-hydrodynamics 3D simulations covering Teff = 6000-11,500 K and logg = 5-6.5 (cgs units) to derive analytical functions to convert spectroscopically determined 1D temperatures and surface gravities to 3D atmospheric parameters. Along with the previously published 3D models, the 1D to 3D corrections are now available for essentially all known convective DA WDs (i.e., logg = 5-9). For low-mass WDs, the correction in temperature is relatively small (a few per cent at the most), but the surface gravities measured from the 3D models are lower by as much as 0.35 dex. We revisit the spectroscopic analysis of the extremely low-mass (ELM) WDs, and demonstrate that the 3D models largely resolve the discrepancies seen in the radius and mass measurements for relatively cool ELM WDs in eclipsing double WD and WD + milli-second pulsar binary systems. We also use the 3D corrections to revise the boundaries of the ZZ Ceti instability strip, including the recently found ELM pulsators.Comment: 11 pages, 8 figures, accepted for publication in the Astrophysical Journa

Evidence from K2 for rapid rotation in the descendant of an intermediate-mass star

Using patterns in the oscillation frequencies of a white dwarf observed by K2, we have measured the fastest rotation rate, 1.13(02) hr, of any isolated pulsating white dwarf known to date. Balmer-line fits to follow-up spectroscopy from the SOAR telescope show that the star (SDSSJ0837+1856, EPIC 211914185) is a 13,590(340) K, 0.87(03) solar-mass white dwarf. This is the highest mass measured for any pulsating white dwarf with known rotation, suggesting a possible link between high mass and fast rotation. If it is the product of single-star evolution, its progenitor was a roughly 4.0 solar-mass main-sequence B star; we know very little about the angular momentum evolution of such intermediate-mass stars. We explore the possibility that this rapidly rotating white dwarf is the byproduct of a binary merger, which we conclude is unlikely given the pulsation periods observed.Comment: 5 pages, 4 figure, 1 table; accepted for publication in The Astrophysical Journal Letter