721 research outputs found
Power HBT reliability for space applications
High power HBT process developed by UMS for X-band application have been space evaluated under CNES and ESA funding.The reliability assessment plan features high temperatures storage tests,DC life-tests,RF step test stress,ESD and radiation tests.A set of evaluation test vehicles was defined for this purpose.Activation energy have been determined,failure rate calculations are in line with the space requirement
Industrial GaInP/GaAs Power HBT MMIC Process
UMS has developed an industrial power HBT process especially dedicated to power MMICs in the 10GHz frequency range. The process has been qualified and meets the very demanding specifications required for X-Band high power amplifiers. Aside from the obvious RF performances, this includes the demonstration of the necessary stability and reproducibility of the process, associated with state-of-art reliability. It is important to note that the later has been achieved without affecting the high frequency capability of the devices, and demonstrated directly on high power transistors. Thanks to its intrinsic qualities this process can naturally also be used for other applications, like low phase noise voltage controlled oscillators, and power amplifiers at lower frequencies (for mobile phones for instance)
Computational Complexity of Iterated Maps on the Interval (Extended Abstract)
The exact computation of orbits of discrete dynamical systems on the interval
is considered. Therefore, a multiple-precision floating point approach based on
error analysis is chosen and a general algorithm is presented. The correctness
of the algorithm is shown and the computational complexity is analyzed. As a
main result, the computational complexity measure considered here is related to
the Ljapunow exponent of the dynamical system under consideration
From coinductive proofs to exact real arithmetic: theory and applications
Based on a new coinductive characterization of continuous functions we
extract certified programs for exact real number computation from constructive
proofs. The extracted programs construct and combine exact real number
algorithms with respect to the binary signed digit representation of real
numbers. The data type corresponding to the coinductive definition of
continuous functions consists of finitely branching non-wellfounded trees
describing when the algorithm writes and reads digits. We discuss several
examples including the extraction of programs for polynomials up to degree two
and the definite integral of continuous maps
Titration of Power Output During Radiofrequency Catheter Ablation of Atrioventricular Nodal Reentrant Tachycardia
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75088/1/j.1540-8159.1993.tb01609.x.pd
Aspects of Augustana and Swedish America: Essays in honor of Dr. Conrad Bergendoff on his 100th Year
Table of Contents:
Introduction -- Emmet E. Eklund / The Mosaic of Augustana’s Swedish Lutheran Origins -- Maria Erling / Molding Ministers to Fit Congregations: Religious Leadership Among New England’s Swedes -- H. Arnold Barton / Conrad Bergendoff and the Swedish-American Church Language Controversy of the 1920s -- Elder M. Lindahl / The Troublesome Language Question -- Ann Boaden / Weighing the Stars and Hearing the Word: Conrad Bergendoff’s Idea of Christian Higher Education at Augustana College and Theological Seminary -- Mark A. Granquist / Conrad Bergendoff and the LCA Merger of 1962 -- Dag Blanck / North Stars and Vasa Orders: On the Relationship Between Sweden and Swedish American -- Bernhard Erling / The Fourth R--Religious Education in Sweden and the USA -- Judith Belan / Bibliography of the Published Writings of Dr. Conrad Bergendoff, 1963-1995https://digitalcommons.augustana.edu/ahsbooks/1016/thumbnail.jp
Use of a Prescribed Ephedrine/Caffeine Combination and the Risk of Serious Cardiovascular Events: A Registry-based Case-Crossover Study
Ephedrine and herbal ephedra preparations have been shown to induce a small-to-moderate weight loss. Owing to reports on serious cardiovascular events, they were banned from the US market in 2004. There have been no large controlled studies on the possible association between prescribed ephedrine/caffeine and cardiovascular events in general. The authors linked data from four different sources within Statistics Denmark, using data on 257,364 users of prescribed ephedrine/caffeine for the period 1995–2002. The data were analyzed using a case-crossover technique with a composite endpoint: death outside of a hospital, myocardial infarction, or stroke. To account for effects of chronic exposure and effects in naïve users, the authors performed a secondary case-control study nested within the cohort of ephedrine/caffeine ever users. Among 2,316 case subjects, 282 (12.2%) were current users of ephedrine/caffeine. The case-crossover analysis yielded an odds ratio of 0.84 (95% confidence interval: 0.71, 1.00); after adjustment for trends in ephedrine/caffeine use, it was 0.95 (95% confidence interval: 0.79, 1.16). Subgroup analyses revealed no strata with significantly elevated risk. In the case-control substudy, there was no increased risk among naïve users or users with large cumulative doses. Prescribed ephedrine/caffeine was not associated with a substantially increased risk of adverse cardiovascular outcomes in this study
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