@article{63156, abstract = {{GaAs quantum dots (QDs) have recently emerged as state-of-the-art semiconductor sources of polarization-entangled photon pairs, however, without site-control capability. In this work, we present a systematic study of epitaxially grown GaAs/AlxGa1-xAs site-controlled pyramidal QDs possessing unrivaled excitonic uniformity in comparison to their InGaAs counterparts or GaAs QDs fabricated by other techniques. We have experimentally and systematically investigated the binding energy of biexcitons, highlighting the importance of the uniformity of all excitonic lines, rather than concentrating solely on the uniformity of the neutral exciton as a typical figure of merit, as it is normally done in the literature. We present optical signatures of GaAs QDs within a range of ∼250 meV with a remarkable uniformity within each individual sample, the ability to excite the biexciton state resonantly, and a systematic study of the fine-structure splitting (FSS) values—features important for polarization entangled photon emission. While, in general, we observe relatively large FSS distribution and associated non-uniformities, we discuss several strategies to suppress the average FSS values to <15 μeV.}}, author = {{Ranjbar Jahromi, Iman and Juska, Gediminas and Varo, Simone and Basso Basset, Francesco and Salusti, Francesco and Trotta, Rinaldo and Gocalinska, Agnieszka and Mattana, Francesco and Pelucchi, Emanuele}}, issn = {{0003-6951}}, journal = {{Applied Physics Letters}}, number = {{7}}, publisher = {{AIP Publishing}}, title = {{{Optical properties and symmetry optimization of spectrally (excitonically) uniform site-controlled GaAs pyramidal quantum dots}}}, doi = {{10.1063/5.0030296}}, volume = {{118}}, year = {{2021}}, } @article{25212, abstract = {{Finding a good query plan is key to the optimization of query runtime. This holds in particular for cost-based federation engines, which make use of cardinality estimations to achieve this goal. A number of studies compare SPARQL federation engines across different performance metrics, including query runtime, result set completeness and correctness, number of sources selected and number of requests sent. Albeit informative, these metrics are generic and unable to quantify and evaluate the accuracy of the cardinality estimators of cost-based federation engines. To thoroughly evaluate cost-based federation engines, the effect of estimated cardinality errors on the overall query runtime performance must be measured. In this paper, we address this challenge by presenting novel evaluation metrics targeted at a fine-grained benchmarking of cost-based federated SPARQL query engines. We evaluate five cost-based federated SPARQL query engines using existing as well as novel evaluation metrics by using LargeRDFBench queries. Our results provide a detailed analysis of the experimental outcomes that reveal novel insights, useful for the development of future cost-based federated SPARQL query processing engines.}}, author = {{Qudus, Umair and Saleem, Muhammad and Ngonga Ngomo, Axel-Cyrille and Lee, Young-Koo}}, issn = {{2210-4968}}, journal = {{Semantic Web}}, keywords = {{SPARQL, benchmarking, cost-based, cost-free, federated, querying}}, number = {{6}}, pages = {{843--868}}, publisher = {{ISO Press}}, title = {{{An Empirical Evaluation of Cost-based Federated SPARQL Query Processing Engines}}}, doi = {{10.3233/SW-200420}}, volume = {{12}}, year = {{2021}}, } @inproceedings{66219, author = {{Hakert, Christian and Khan, Asif Ali and Chen, Kuan-Hsun and Hameed, Fazal and Castrillon, Jeronimo and Chen, Jian-Jia}}, booktitle = {{2021 58th ACM/IEEE Design Automation Conference (DAC)}}, publisher = {{IEEE}}, title = {{{BLOwing Trees to the Ground: Layout Optimization of Decision Trees on Racetrack Memory}}}, doi = {{10.1109/dac18074.2021.9586167}}, year = {{2021}}, } @article{66216, abstract = {{AbstractThe predictive performance of a machine learning model highly depends on the corresponding hyper-parameter setting. Hence, hyper-parameter tuning is often indispensable. Normally such tuning requires the dedicated machine learning model to be trained and evaluated on centralized data to obtain a performance estimate. However, in a distributed machine learning scenario, it is not always possible to collect all the data from all nodes due to privacy concerns or storage limitations. Moreover, if data has to be transferred through low bandwidth connections it reduces the time available for tuning. Model-Based Optimization (MBO) is one state-of-the-art method for tuning hyper-parameters but the application on distributed machine learning models or federated learning lacks research. This work proposes a framework$$\textit{MODES}$$MODESthat allows to deploy MBO on resource-constrained distributed embedded systems. Each node trains an individual model based on its local data. The goal is to optimize the combined prediction accuracy. The presented framework offers two optimization modes: (1)$$\textit{MODES}$$MODES-B considers the whole ensemble as a single black box and optimizes the hyper-parameters of each individual model jointly, and (2)$$\textit{MODES}$$MODES-I considers all models as clones of the same black box which allows it to efficiently parallelize the optimization in a distributed setting. We evaluate$$\textit{MODES}$$MODESby conducting experiments on the optimization for the hyper-parameters of a random forest and a multi-layer perceptron. The experimental results demonstrate that, with an improvement in terms of mean accuracy ($$\textit{MODES}$$MODES-B), run-time efficiency ($$\textit{MODES}$$MODES-I), and statistical stability for both modes,$$\textit{MODES}$$MODESoutperforms the baseline, i.e., carry out tuning with MBO on each node individually with its local sub-data set.}}, author = {{Shi, Junjie and Bian, Jiang and Richter, Jakob and Chen, Kuan-Hsun and Rahnenführer, Jörg and Xiong, Haoyi and Chen, Jian-Jia}}, issn = {{0885-6125}}, journal = {{Machine Learning}}, number = {{6}}, pages = {{1527--1547}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{MODES: model-based optimization on distributed embedded systems}}}, doi = {{10.1007/s10994-021-06014-6}}, volume = {{110}}, year = {{2021}}, } @inbook{19561, author = {{Sellmann, Meinolf and Tierney, Kevin}}, booktitle = {{Lecture Notes in Computer Science}}, isbn = {{9783030535513}}, issn = {{0302-9743}}, keywords = {{pc2-ressources}}, title = {{{Hyper-parameterized Dialectic Search for Non-linear Box-Constrained Optimization with Heterogenous Variable Types}}}, doi = {{10.1007/978-3-030-53552-0_12}}, year = {{2020}}, } @unpublished{19603, abstract = {{Micro- and smart grids (MSG) play an important role both for integrating renewable energy sources in conventional electricity grids and for providing power supply in remote areas. Modern MSGs are largely driven by power electronic converters due to their high efficiency and flexibility. Nevertheless, controlling MSGs is a challenging task due to highest requirements on energy availability, safety and voltage quality within a wide range of different MSG topologies. This results in a high demand for comprehensive testing of new control concepts during their development phase and comparisons with the state of the art in order to ensure their feasibility. This applies in particular to data-driven control approaches from the field of reinforcement learning (RL), whose stability and operating behavior can hardly be evaluated a priori. Therefore, the OpenModelica Microgrid Gym (OMG) package, an open-source software toolbox for the simulation and control optimization of MSGs, is proposed. It is capable of modeling and simulating arbitrary MSG topologies and offers a Python-based interface for plug \& play controller testing. In particular, the standardized OpenAI Gym interface allows for easy RL-based controller integration. Besides the presentation of the OMG toolbox, application examples are highlighted including safe Bayesian optimization for low-level controller tuning.}}, author = {{Bode, Henrik and Heid, Stefan Helmut and Weber, Daniel and Hüllermeier, Eyke and Wallscheid, Oliver}}, booktitle = {{arXiv:2005.04869}}, title = {{{Towards a Scalable and Flexible Simulation and Testing Environment Toolbox for Intelligent Microgrid Control}}}, year = {{2020}}, } @inproceedings{19606, abstract = {{Mobile shopping apps have been using Augmented Reality (AR) in the last years to place their products in the environment of the customer. While this is possible with atomic 3D objects, there is is still a lack in the runtime configuration of 3D object compositions based on user needs and environmental constraints. For this, we previously developed an approach for model-based AR-assisted product configuration based on the concept of Dynamic Software Product Lines. In this demonstration paper, we present the corresponding tool support ProConAR in the form of a Product Modeler and a Product Configurator. While the Product Modeler is an Angular web app that splits products (e.g. table) up into atomic parts (e.g. tabletop, table legs, funnier) and saves it within a configuration model, the Product Configurator is an Android client that uses the configuration model to place different product configurations within the environment of the customer. We show technical details of our ready to use tool-chain ProConAR by describing its implementation and usage as well as pointing out future research directions.}}, author = {{Gottschalk, Sebastian and Yigitbas, Enes and Schmidt, Eugen and Engels, Gregor}}, booktitle = {{Human-Centered Software Engineering. HCSE 2020}}, editor = {{Bernhaupt, Regina and Ardito, Carmelo and Sauer, Stefan}}, keywords = {{Product Configuration, Augmented Reality, Model-based, Tool Support}}, location = {{Eindhoven}}, publisher = {{Springer}}, title = {{{ProConAR: A Tool Support for Model-based AR Product Configuration}}}, doi = {{10.1007/978-3-030-64266-2_14}}, volume = {{12481}}, year = {{2020}}, } @inproceedings{20164, abstract = {{Upcoming sensing applications (acoustic or video) will have high processing requirements not satisfiable by a single node or need input from multiple sources (e.g., speaker localization). Offloading these applications to cloud or mobile edge is an option, but when running in a wireless senor network (WSN), it might entail needlessly high data rate and latency. An alternative is to spread processing inside the WSN, which is particularly attractive if the application comprises individual components. This scenario is typical for applications like acoustic signal processing. Mapping components to nodes can be formulated as wireless version of the NP-hard Virtual Network Embedding (VNE) problem, for which various heuristics exist. We propose a Reinforcement Learning (RL) framework, which relies on Q-Learning and uses either Greedy Epsilon or Epsilon Decay for exploration. We compare both exploration methods to the result of an optimization approach and show empirically that the RL framework achieves good results in terms of network delay within few number of steps.}}, author = {{Afifi, Haitham and Karl, Holger}}, booktitle = {{2020 Thirteenth International Workshop on Selected Topics in Mobile and Wireless Computing (STWiMob'2020)}}, title = {{{Reinforcement Learning for Virtual Network Embedding in Wireless Sensor Networks}}}, year = {{2020}}, } @article{20233, abstract = {{The challenge of designing new tunable nonlinear dielectric materials with tailored properties has attracted an increasing amount of interest recently. Herein, we study the effective nonlinear dielectric response of a stochastic paraelectric-dielectric composite consisting of equilibrium distributions of circular and partially penetrable disks (or parallel, infinitely long, identical, partially penetrable, circular cylinders) of a dielectric phase randomly dispersed in a continuous matrix of a paraelectric phase. The random microstructures were generated using the Metropolis Monte Carlo algorithm. The evaluation of the effective permittivity and tunability were carried out by employing either a Landau thermodynamic model or its Johnson’s approximation to describe the field-dependent permittivity of the paraelectric phase and solving continuum-electrostatics equations using finite element calculations. We reveal that the percolation threshold in this composite governs the critical behavior of the effective permittivity and tunability. For microstructures below the percolation threshold, our simulations demonstrate a strong nonlinear behaviour of the field-dependent effective permittivity and very high tunability that increases as a function of dielectric phase concentration. Above the percolation threshold, the effective permittivity shows the tendency to linearization and the tunability dramatically drops down. The highly reduced permittivity and extraordinarily high tunability are obtained for the composites with dielectric impenetrable disks at high concentrations, in which the triggering of the percolation transition is avoided. The reported results cast light on distinct nonlinear behaviour of 2D and 3D stochastic composites and can guide the design of novel composites with the controlled morphology and tailored permittivity and tunability.}}, author = {{Myroshnychenko, Viktor and Smirnov, Stanislav and Jose, Pious Mathews Mulavarickal and Brosseau, Christian and Förstner, Jens}}, issn = {{1359-6454}}, journal = {{Acta Materialia}}, pages = {{116432}}, title = {{{Nonlinear dielectric properties of random paraelectric-dielectric composites}}}, doi = {{10.1016/j.actamat.2020.10.051}}, volume = {{203}}, year = {{2020}}, } @proceedings{20278, editor = {{Ahrendt, Wolfgang and Wehrheim, Heike}}, isbn = {{978-3-030-50994-1}}, publisher = {{Springer}}, title = {{{Tests and Proofs - 14th International Conference, TAP@STAF 2020, Bergen, Norway, June 22-23, 2020, Proceedings [postponed]}}}, doi = {{10.1007/978-3-030-50995-8}}, volume = {{12165}}, year = {{2020}}, } @article{28011, author = {{Brand-Miller, Jennie and Buyken, Anette}}, issn = {{1078-8956}}, journal = {{Nature Medicine}}, pages = {{828--830}}, title = {{{Mapping postprandial responses sets the scene for targeted dietary advice}}}, doi = {{10.1038/s41591-020-0909-1}}, year = {{2020}}, } @inproceedings{24146, author = {{Heid, Stefan Helmut and Ramaswamy, Arunselvan and Hüllermeier, Eyke}}, booktitle = {{Proceedings-30. Workshop Computational Intelligence: Berlin, 26.-27. November 2020}}, pages = {{247}}, title = {{{Constrained Multi-Agent Optimization with Unbounded Information Delay}}}, volume = {{26}}, year = {{2020}}, } @inproceedings{24203, author = {{Moritzer, Elmar and Hillemeyer, Johannes}}, booktitle = {{6. Fachkonferenz 3D-Druck in der Automobielindustrie}}, location = {{Hamburg}}, title = {{{Additiveteile Direktverschrauben}}}, year = {{2020}}, } @article{24312, author = {{Vogtschmidt, Sascha and Fiebig, Isabel and Schöppner, Volker}}, journal = {{Joining Plastics}}, number = {{3-4}}, title = {{{Wechseldehnungsschweißen - Entwicklung einer Fügetechnologie für 3D-Geometrien}}}, year = {{2020}}, } @inproceedings{24318, author = {{Vogtschmidt, Sascha and Schöppner, Volker}}, booktitle = {{DVS CONGRESS 2020 - Große Schweißtechnische Tagung}}, title = {{{Wechseldehnungsschweißen - Entwicklung einer Fügetechnologie für 3D-Geometrien}}}, volume = {{365}}, year = {{2020}}, } @inproceedings{24478, author = {{Moritzer, Elmar and Wächter, Julian}}, location = {{Karlsruhe}}, title = {{{From filament production to material qualification for the FDM process}}}, year = {{2020}}, } @article{26526, author = {{Gappa, Monika and Filipiak‐Pittroff, Birgit and Libuda, Lars and Berg, Andrea and Koletzko, Sibylle and Bauer, Carl‐Peter and Heinrich, Joachim and Schikowski, Tamara and Berdel, Dietrich and Standl, Marie}}, issn = {{0105-4538}}, journal = {{Allergy}}, pages = {{1903--1907}}, title = {{{Long‐term effects of hydrolyzed formulae on atopic diseases in the GINI study}}}, doi = {{10.1111/all.14709}}, year = {{2020}}, } @article{26527, abstract = {{Abstract Background While observational studies revealed an inverse association between serum 25(OH)vitamin D (25(OH)D) and the risk of attention deficit/hyperactivity disorder (ADHD), the causality of this relationship remains unclear. Methods We conducted a bidirectional two-sample Mendelian Randomization (MR) study to examine whether 25(OH)D has an effect on the risk to develop ADHD or vice versa. Information on single nucleotide polymorphisms (SNP) associated with serum 25(OH)D was obtained from a genome-wide association study (GWAS) considering phenotype data from 79,366 individuals of European ancestry. Data on risk for ADHD were derived from a GWAS analysis with 20,183 individuals diagnosed with ADHD and 35,191 controls. For our analysis, we considered effect sizes based on the European participants (19,099 cases and 34,194 controls). Results Single SNP analyses showed a causal effect of vitamin D on ADHD risk for only one SNP (rs12785878, p = 0.024). The overall MR estimates did not reveal a causal effect of 25(OH)D on risk for ADHD. In the reverse analysis, neither any single nor the multi-SNP MR analyses showed a causal effect of ADHD on 25(OH)D. Conclusion Results from this two-sample MR study did not confirm a causal effect of 25(OH)D on ADHD or vice versa. Accordingly, our study does not provide evidence that improving 25(OH)D via supplementation could reduce the risk of developing ADHD. }}, author = {{Libuda, Lars and Naaresh, Roaa and Ludwig, Christine and Laabs, Björn-Hergen and Antel, Jochen and Föcker, Manuel and Hebebrand, Johannes and Hinney, Anke and Peters, Triinu}}, issn = {{1436-6207}}, journal = {{European Journal of Nutrition}}, pages = {{2581--2591}}, title = {{{A mendelian randomization study on causal effects of 25(OH)vitamin D levels on attention deficit/hyperactivity disorder}}}, doi = {{10.1007/s00394-020-02439-2}}, year = {{2020}}, } @article{26529, abstract = {{Abstract Purpose The influences of nutrition in childhood on puberty onset could have sustained consequences for health and wellbeing later in life. The aim of this study was to investigate the prospective association of diet quality prior to puberty with the timing of puberty onset. Methods We considered data from 3983 SCCNG (Southwest China Childhood Nutrition and Growth) study participants with dietary data, anthropometric measurement, and information on potential confounders at their baseline assessment (mean age: 7.1 years for girls and 7.3 years for boys; mean length of follow-up was 4.2 years). Cox proportional hazard regression estimating hazard ratios (HRs) and 95% confidence intervals (CIs) were used to examine the relationship between diet quality and puberty onset. Dietary intake at baseline was assessed using a validated food frequency questionnaire. Diet quality was determined using the Chinese Children Dietary Index (CCDI) which measures adherence to current dietary recommendations (theoretical range: 0–160 points). Age at Tanner stage 2 for breast/genital development (B2/G2), menarche or voice break (M/VB) were used as pubertal markers. Results The CCDI score ranged from 56.2 to 136.3 for girls and 46.1–131.5 for boys. Pubertal markers consistently indicate that girls and boys with higher diet quality were more likely to enter their puberty later than their counterparts with lower CCDI scores (higher vs. lower CCDI tertiles: adjusted HR for age at B2: 0.85 (95% CI, 0.81–0.94), p for trend = 0.02; G2: 0.86 (95% CI,0.80–0.96), p for trend = 0.02; M: 0.86 (95% CI,0.80–0.95), p for trend = 0.02; VB: 0.86 (95% CI,0.79–0.98), p for trend = 0.03), after adjustment for paternal education level, baseline energy intake, and pre-pubertal body fat. Conclusions Our data suggested a later puberty onset and later timing of progressed puberty stages in children with a high diet quality, which were independent of pre-pubertal body fat. }}, author = {{Duan, Ruonan and Qiao, Tian and Chen, Yue and Chen, Mengxue and Xue, Hongmei and Zhou, Xue and Yang, Mingzhe and Liu, Yan and Zhao, Li and Libuda, Lars and Cheng, Guo}}, issn = {{1436-6207}}, journal = {{European Journal of Nutrition}}, pages = {{2423--2434}}, title = {{{The overall diet quality in childhood is prospectively associated with the timing of puberty}}}, doi = {{10.1007/s00394-020-02425-8}}, year = {{2020}}, } @book{26872, author = {{Klünder, Nina}}, pages = {{135}}, publisher = {{Beltz Juventa}}, title = {{{Die Ernährungsversorgung in Familien zwischen Zeit, Alltag und Haushaltsführung. Eine Mixed-Methods-Untersuchung}}}, year = {{2020}}, }