426 research outputs found
Megasonic Enhanced Electrodeposition
A novel way of filling high aspect ratio vertical interconnection (microvias)
with an aspect ratio of >2:1 is presented. High frequency acoustic streaming at
megasonic frequencies enables the decrease of the Nernst-diffusion layer down
to the sub-micron range, allowing thereby conformal electrodeposition in deep
grooves. Higher throughput and better control over the deposition properties
are possible for the manufacturing of interconnections and metal-based MEMS.Comment: Submitted on behalf of EDA Publishing Association
(http://irevues.inist.fr/handle/2042/16838
Dealing with Unknown Variances in Best-Arm Identification
The problem of identifying the best arm among a collection of items having
Gaussian rewards distribution is well understood when the variances are known.
Despite its practical relevance for many applications, few works studied it for
unknown variances. In this paper we introduce and analyze two approaches to
deal with unknown variances, either by plugging in the empirical variance or by
adapting the transportation costs. In order to calibrate our two stopping
rules, we derive new time-uniform concentration inequalities, which are of
independent interest. Then, we illustrate the theoretical and empirical
performances of our two sampling rule wrappers on Track-and-Stop and on a Top
Two algorithm. Moreover, by quantifying the impact on the sample complexity of
not knowing the variances, we reveal that it is rather small.Comment: 73 pages, 5 figures, 3 tables. To be published in the 34th
International Conference on Algorithmic Learning Theory, Singapore, 202
ELSID-diabetes study-evaluation of a large scale implementation of disease management programmes for patients with type 2 diabetes. Rationale, design and conduct : a study protocol
Background: Diabetes model projects in different regions of Germany including interventions such as quality circles, patient education and documentation of medical findings have shown improvements of HbA1c levels, blood pressure and occurrence of hypoglycaemia in before-after studies (without control group). In 2002 the German Ministry of Health defined legal regulations for the introduction of nationwide disease management programs (DMP) to improve the quality of care in chronically ill patients. In April 2003 the first DMP for patients with type 2 diabetes was accredited. The evaluation of the DMP is essential and has been made obligatory in Germany by the Fifth Book of Social Code. The aim of the study is to assess the effectiveness of DMP by example of type 2 diabetes in the primary care setting of two German federal states (Rheinland-Pfalz and Sachsen-Anhalt). Methods/Design: The study is three-armed: a prospective cluster-randomized comparison of two interventions (DMP 1 and DMP 2) against routine care without DMP as control group. In the DMP group 1 the patients are treated according to the current situation within the German-Diabetes-DMP. The DMP group 2 represents diabetic care within ideally implemented DMP providing additional interventions (e.g. quality circles, outreach visits). According to a sample size calculation a sample size of 200 GPs (each GP including 20 patients) will be required for the comparison of DMP 1 and DMP 2 considering possible drop-outs. For the comparison with routine care 4000 patients identified by diabetic tracer medication and age (> 50 years) will be analyzed. Discussion: This study will evaluate the effectiveness of the German Diabetes-DMP compared to a Diabetes-DMP providing additional interventions and routine care in the primary care setting of two different German federal states
Self-adjusting Population Sizes for the -EA on Monotone Functions
We study the -EA with mutation rate for , where
the population size is adaptively controlled with the -success rule.
Recently, Hevia Fajardo and Sudholt have shown that this setup with is
efficient on \onemax for , but inefficient if . Surprisingly,
the hardest part is not close to the optimum, but rather at linear distance. We
show that this behavior is not specific to \onemax. If is small, then the
algorithm is efficient on all monotone functions, and if is large, then it
needs superpolynomial time on all monotone functions. In the former case, for
we show a upper bound for the number of generations and for the number of function evaluations, and for we show
generations and evaluations. We also show formally that
optimization is always fast, regardless of , if the algorithm starts in
proximity of the optimum. All results also hold in a dynamic environment where
the fitness function changes in each generation
Schutz von SHV-relevanten Daten unter der Lupe
Der Schweizerische Hebammenverband hat seine internen Prozesse analysiert und wo nötig der künftig in Kraft tretenden Revision des Schweizerischen Bundesgesetzes über den Datenschutz angepasst. Wie schützt die Zürcher Hochschule für Angewandte Wissenschaften die Daten bei der Auswertung der Statistik der frei praktizierenden Hebammen? Und wie verfahren die Anbieter der Softwares MoonCare und Artemis Hebamme
Size-Ramsey numbers of structurally sparse graphs
Size-Ramsey numbers are a central notion in combinatorics and have been
widely studied since their introduction by Erd\H{o}s, Faudree, Rousseau and
Schelp in 1978. Research has mainly focused on the size-Ramsey numbers of
-vertex graphs with constant maximum degree . For example, graphs
which also have constant treewidth are known to have linear size-Ramsey
numbers. On the other extreme, the canonical examples of graphs of unbounded
treewidth are the grid graphs, for which the best known bound has only very
recently been improved from to by Conlon, Nenadov and
Truji\'c. In this paper, we prove a common generalization of these results by
establishing new bounds on the size-Ramsey numbers in terms of treewidth (which
may grow as a function of ). As a special case, this yields a bound of
for proper minor-closed classes of graphs. In
particular, this bound applies to planar graphs, addressing a question of Wood.
Our proof combines methods from structural graph theory and classic
Ramsey-theoretic embedding techniques, taking advantage of the product
structure exhibited by graphs with bounded treewidth.Comment: 21 page
Top Two Algorithms Revisited
Top Two algorithms arose as an adaptation of Thompson sampling to best arm
identification in multi-armed bandit models (Russo, 2016), for parametric
families of arms. They select the next arm to sample from by randomizing among
two candidate arms, a leader and a challenger. Despite their good empirical
performance, theoretical guarantees for fixed-confidence best arm
identification have only been obtained when the arms are Gaussian with known
variances. In this paper, we provide a general analysis of Top Two methods,
which identifies desirable properties of the leader, the challenger, and the
(possibly non-parametric) distributions of the arms. As a result, we obtain
theoretically supported Top Two algorithms for best arm identification with
bounded distributions. Our proof method demonstrates in particular that the
sampling step used to select the leader inherited from Thompson sampling can be
replaced by other choices, like selecting the empirical best arm.Comment: 75 pages, 8 figures, 3 table
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