Efficient passive network description of IC conducted emission models for model reduction

This article adresses the model reduction of IC conducted emission models. A method to efficiently deal with the high number of independent sources in IC conducted emission models, which are a strong limitation for model order reduction, is presented. A network alteration is proposed, which allows for a much higher model reduction than standard approaches. The system of the altered network can be more efficiently reduced with standard model order reduction algorithms in order to speed up frequency-simulations. Synthesising the reduced system into a passive electrical network enables fast time-simulations to be made with circuit simulators. The whole procedure is validated by reducing an example of an IC conducted emission model of an 32 Bit microcontroller.BMBF/01M 3169 ABMBF/01M 3169 DBMBF/01M 3169

Efficient modelling of IC conducted emission for power integrity analysis

In this paper two methodologies to reduce the complexity of IC conducted emission models for Power Integrity analysis in ICs are presented. The methodologies differ concerning the applicability in simulation tools, complexity and accuracy of the generated models. The first methodology uses a complex model and reduces its order to generate a model with a fewer number of elements. This methodology therefore involves a model order reduction approach. A second minimum complexity, module based modelling approach is introduced for rough estimations, as the order reduced model is still too complex for some applications. The two methodologies are applied to an IC conducted emission model of two digital modules of a 32 Bit microcontroller. The results of the three models are compared and discussed. Fields of application for the introduced modelling approaches are the estimation of the magnitude and time behaviour of the supply current as well as the determination of the number and position of the IC's supply pins.BMBF/01M 3169 ABMBF/01M 3169 DBMBF/01M 3169

Model reduction of parasitic coupling networks of mixed-signal VLSI circuits

Purpose: This paper aims to present a method for the efficient reduction of networks modelling parasitic couplings in very-large-scale integration (VLSI) circuits. Design/methodology/approach: The parasitic effects are modelled by large RLC networks and current sources for the digital switching currents. Based on the determined behaviour of the digital modules, an efficient description of these networks is proposed, which allows for a more efficient model reduction than standard methods. Findings: The proposed method enables a fast and efficient simulation of the parasitic effects. Additionally, an extension of the reduction method to elements, which incorporate some supply voltage dependence to model the internal currents more precisely than independent current sources is presented. Practical implications: The presented method can be applied to large electrical networks, used in the modelling of parasitic effects, for reducing their size. A reduced model is created which can be used in investigations with circuit simulators requiring a lowered computational effort. Originality/value: Contrary to existing methods, the presented method includes the knowledge of the behaviour of the sources in the model to enhance the model reduction process. © Emerald Group Publishing Limited 0332-1649

Erforschendes und entdeckendes Lernen in Technikwochen

Das frühe Wecken von Begeisterung und Interesse für Naturwissenschaft und Technik bei Schülerinnen und Schülern ist der Schlüssel zur erfolgreichen Gestaltung unserer zunehmend technisierten Welt. Erforschendes und entdeckendes Lernen in Technikwochen möchte einen Beitrag dazu leisten, das Interesse von Schülerinnen und Schülern an technischen Themen zu wecken. Die im Folgenden angebotenen Unterrichtsbeispiele basieren auf spannenden und motivierenden Themenstellungen, die von den Autorinnen und Autoren erprobt und mit Sachinformationen und methodisch-didaktischen Hinweisen zur Förderung der allgemeinen Technischen Bildung aufbereitet wurden. Natürlich sind die Faktoren für lernwirksamen Unterricht immer vielfältig. Soziokulturelle Aspekte wie die Klassensituation, örtliche Faktoren wie die Ausstattung der Schulen, das Vorwissen der Schülerinnen und Schüler aber auch die Haltung, die Einstellung und das fachspezifische Wissen und Können der Lehrpersonen entscheiden maßgeblich über die erfolgreiche Umsetzung von Techniktagen oder -wochen mit. Die Unterrichtsbeispiele in diesem Buch sollen Anregungen liefern, wie fächerverbindender, technikorientierter, erforschend entdeckender und nachhaltiger Unterricht in Kindergarten, Primar- und Sekundarstufe implementiert werden kann. Auch fachfremd unterrichtende Personen werden in den didaktischen Hinweisen zahlreiche Ratschläge finden, um sich vielleicht doch einmal an das ein oder andere bisher gemiedene Thema zu wagen. Die einzelnen Themen in diesem Buch sind einerseits unabhängig voneinander umsetzbar, andererseits lassen sie sich teilweise gut kombinieren. Sie sind so angelegt, dass sie unkompliziert und ohne großen materiellen Aufwand in Projekttagen oder auch im regulären Unterricht der obligatorischen Schule durchgeführt werden können. Zu allen Themen finden Sie Bauanleitungen, Versuchsbeschreibungen oder Aufgaben sowie Hinweise zu Methodik oder Medienwahl. Einzelne Teile der Themen oder beiliegende Arbeitsblätter können als Kopiervorlage für den Unterricht verwendet werden. Das Buch mit seinen vielfältigen Vorschlägen versteht sich nicht als Bildungskonserve, in der fertige Unterrichtsrezepte beliebig adaptierbar sind. Einige Fragestellungen werden individuell durch die Situation in den jeweiligen Klassen zu entwickeln und auszugestalten sein. Außerdem ist die Weiterentwicklung der vorliegenden Konzepte wünschenswert und sinnvoll.+repphzhbib2019

Model order reduction of linear time invariant systems

This paper addresses issues related to the order reduction of systems with multiple input/output ports. The order reduction is divided up into two steps. The first step is the standard order reduction method based on the multipoint approximation of system matrices by applying Krylov subspace. The second step is based on the rejection of the weak part of a system. To recognise the weak system part, Lyapunov equations are used. Thus, this paper introduces efficient solutions of the Lyapunov equations for port to port subsystems.BMBF/01 M 3169

Annotation-efficient learning of surgical instrument activity in neurosurgery

Machine learning-based solutions rely heavily on the quality and quantity of the training data. In the medical domain, the main challenge is to acquire rich and diverse annotated datasets for training. We propose to decrease the annotation efforts and further diversify the dataset by introducing an annotation-efficient learning workflow. Instead of costly pixel-level annotation, we require only image-level labels as the remainder is covered by simulation. Thus, we obtain a large-scale dataset with realistic images and accurateground truth annotations. We use this dataset for theinstrument localization activity task together with a student-teacher approach. We demonstrate the benefits of our workflow compared to state-of-the-art methods in instrument localization that are trained only on clinical datasets, which are fully annotated by human experts

Clearing the Dust from Globular Clusters

Recent Spitzer observations of the globular cluster M15 detected dust associated with its intracluster medium. Surprisingly, these observations imply that the dust must be very short-lived compared to the time since the last Galactic plane crossing of the cluster.Here we propose a simple mechanism to explain this short lifetime. We argue that the kinetic energy of the material ejected during a stellar collision may be sufficient to remove the gas and dust entirely from a cluster, or to remove the gas as a wind, in addition to partially destroying the dust. By calculating the rate of stellar collisions using an N-body model for the cluster, we find remarkable agreement between the average time between collisions and the inferred dust lifetime in this cluster, suggesting a possible close relation between the two phenomena. Furthermore, we also obtain the birthrate of blue stragglers formed through collisions in M15. By comparing with the observed number of blue stragglers, we derive an upper limit for their average lifetime which turns out to be consistent with recent model calculations, thereby lending further support to our model.Comment: 4 pages, 1 figure, to appear in ApJ Letter

Synthetic data generation for optical flow evaluation in the neurosurgical domain

Towards computer-assisted neurosurgery, scene understanding algorithms for microscope video data are required. Previous work utilizes optical flow to extract spatio-temporal context from neurosurgical video sequences. However, to select an appropriate optical flow method, we need to analyze which algorithm yields the highest accuracy for the neurosurgical domain. Currently, there are no benchmark datasets available for neurosurgery. In our work, we present an approach to generate synthetic data for optical flow evaluation on the neurosurgical domain. We simulate image sequences and thereby take into account domain-specific visual conditions such as surgical instrument motion. Then, we evaluate two optical flow algorithms, Farneback and PWC-Net, on our synthetic data. Qualitative and quantitative assessments confirm that our data can be used to evaluate optical flow for the neurosurgical domain. Future work will concentrate on extending the method by modeling additional effects in neurosurgery such as elastic background motion

Leveraging the Potential of Conversational Agents: Quality Criteria for the Continuous Evaluation and Improvement

Contemporary organizations are increasingly adopting conversational agents (CAs) as intelligent and natural language-based solutions for providing services and information. CAs promote new forms of personalization, speed, cost-effectiveness, and automation. However, despite their hype in research and practice, organizations fail to sustain CAs in operations. They struggle to leverage CAs’ potential because they lack knowledge on how to evaluate and improve the quality of CAs throughout their lifecycle. We build on this research gap by conducting a design science research (DSR) project, aggregating insights from the literature and practice to derive a validated set of quality criteria for CAs. Our study contributes to CA research and guides practitioners by providing a blueprint to structure the evaluation of CAs to discover areas for systematic improvement

Towards truly simultaneous PIXE and RBS analysis of layered objects in cultural heritage

For a long time, RBS and PIXE techniques have been used in the field of cultural heritage. Although the complementarity of both techniques has long been acknowledged, its full potential has not been yet developed due to the lack of general purpose software tools for analysing the data from both techniques in a coherent way. In this work we provide an example of how the recent addition of PIXE to the set of techniques supported by the DataFurnace code can significantly change this situation. We present a case in which a non homogeneous sample (an oxidized metal from a photographic plate -heliography- made by Niepce in 1827) is analysed using RBS and PIXE in a straightforward and powerful way that can only be performed with a code that treats both techniques simultaneously as a part of one single and coherent analysis. The optimization capabilities of DataFurnace, allowed us to obtain the composition profiles for these samples in a very simple way.Comment: 9 pages, 3 figure