@inproceedings{29459, abstract = {{Transistor and interconnect wearout is accelerated with transistor scaling resulting in timing variations and consequently reliability challenges in digital circuits. With the emergence of new issues like Electro-migration these problems are getting more crucial. Age monitoring methods can be used to predict and deal with the aging problem. Selecting appropriate locations for placement of aging monitors is an important issue. In this work we propose a procedure for selection of appropriate internal nodes that expose smaller overheads to the circuit, using correlation between nodes and the shareability amongst them. To select internal nodes, we first prune some nodes based on some attributes and thus provide a near-optimal solution that can effectively get a number of internal nodes and consider the effects of electro-migration as well. We have applied our proposed scheme to several processors and ITC benchmarks and have looked at its effectiveness for these circuits.}}, author = {{Sadeghi-Kohan, Somayeh and Vafaei, Arash and Navabi, Zainalabedin}}, booktitle = {{2018 IEEE 24th International Symposium on On-Line Testing And Robust System Design (IOLTS)}}, publisher = {{IEEE}}, title = {{{Near-Optimal Node Selection Procedure for Aging Monitor Placement}}}, doi = {{10.1109/iolts.2018.8474120}}, year = {{2018}}, } @inproceedings{24187, abstract = {{In this paper, we present a monolithically integrated coherent receiver with on-chip grating couplers, 90° hybrid, photodiodes and transimpedance amplifiers. A transimpedance gain of 7.7 kΩ was achieved by the amplifiers. An opto-electrical 3 dB bandwidth of 34 GHz for in-phase and quadrature channel was measured. A real-time data transmission of 64 GBd-QPSK (128 Gb/s) for a single polarization was performed.}}, author = {{Gudyriev, Sergiy and Kress, Christian and Zwickel, Heiner and Kemal, Juned N. and Lischke, Stefan and Zimmermann, Lars and Koos, Christian and Scheytt, Christoph}}, booktitle = {{IEEE/OSA Journal of Lightwave Technology}}, pages = {{1--1}}, title = {{{Coherent ePIC Receiver for 64 GBaud QPSK in 0.25μm Photonic BiCMOS Technology}}}, doi = {{10.1109/JLT.2018.2881107}}, year = {{2018}}, } @unpublished{19940, abstract = {{Two smooth map germs are right-equivalent if and only if they generate two Lagrangian submanifolds in a cotangent bundle which have the same contact with the zero-section. In this paper we provide a reverse direction to this classical result of Golubitsky and Guillemin. Two Lagrangian submanifolds of a symplectic manifold have the same contact with a third Lagrangian submanifold if and only if the intersection problems correspond to stably right equivalent map germs. We, therefore, obtain a correspondence between local Lagrangian intersection problems and catastrophe theory while the classical version only captures tangential intersections. The correspondence is defined independently of any Lagrangian fibration of the ambient symplectic manifold, in contrast to other classical results. Moreover, we provide an extension of the correspondence to families of local Lagrangian intersection problems. This gives rise to a framework which allows a natural transportation of the notions of catastrophe theory such as stability, unfolding and (uni-)versality to the geometric setting such that we obtain a classification of families of local Lagrangian intersection problems. An application is the classification of Lagrangian boundary value problems for symplectic maps.}}, author = {{Offen, Christian}}, booktitle = {{arXiv:1811.10165}}, title = {{{Local intersections of Lagrangian manifolds correspond to catastrophe theory}}}, year = {{2018}}, } @article{19943, abstract = {{In this paper we continue our study of bifurcations of solutions of boundary-value problems for symplectic maps arising as Hamiltonian diffeomorphisms. These have been shown to be connected to catastrophe theory via generating functions and ordinary and reversal phase space symmetries have been considered. Here we present a convenient, coordinate free framework to analyse separated Lagrangian boundary value problems which include classical Dirichlet, Neumann and Robin boundary value problems. The framework is then used to prove the existence of obstructions arising from conformal symplectic symmetries on the bifurcation behaviour of solutions to Hamiltonian boundary value problems. Under non-degeneracy conditions, a group action by conformal symplectic symmetries has the effect that the flow map cannot degenerate in a direction which is tangential to the action. This imposes restrictions on which singularities can occur in boundary value problems. Our results generalise classical results about conjugate loci on Riemannian manifolds to a large class of Hamiltonian boundary value problems with, for example, scaling symmetries. }}, author = {{McLachlan, Robert I and Offen, Christian}}, journal = {{New Zealand Journal of Mathematics}}, keywords = {{Hamiltonian boundary value problems, singularities, conformal symplectic geometry, catastrophe theory, conjugate loci}}, pages = {{83--99}}, title = {{{Hamiltonian boundary value problems, conformal symplectic symmetries, and conjugate loci}}}, doi = {{10.53733/34 }}, volume = {{48}}, year = {{2018}}, } @inproceedings{1588, abstract = {{The exploration of FPGAs as accelerators for scientific simulations has so far mostly been focused on small kernels of methods working on regular data structures, for example in the form of stencil computations for finite difference methods. In computational sciences, often more advanced methods are employed that promise better stability, convergence, locality and scaling. Unstructured meshes are shown to be more effective and more accurate, compared to regular grids, in representing computation domains of various shapes. Using unstructured meshes, the discontinuous Galerkin method preserves the ability to perform explicit local update operations for simulations in the time domain. In this work, we investigate FPGAs as target platform for an implementation of the nodal discontinuous Galerkin method to find time-domain solutions of Maxwell's equations in an unstructured mesh. When maximizing data reuse and fitting constant coefficients into suitably partitioned on-chip memory, high computational intensity allows us to implement and feed wide data paths with hundreds of floating point operators. By decoupling off-chip memory accesses from the computations, high memory bandwidth can be sustained, even for the irregular access pattern required by parts of the application. Using the Intel/Altera OpenCL SDK for FPGAs, we present different implementation variants for different polynomial orders of the method. In different phases of the algorithm, either computational or bandwidth limits of the Arria 10 platform are almost reached, thus outperforming a highly multithreaded CPU implementation by around 2x.}}, author = {{Kenter, Tobias and Mahale, Gopinath and Alhaddad, Samer and Grynko, Yevgen and Schmitt, Christian and Afzal, Ayesha and Hannig, Frank and Förstner, Jens and Plessl, Christian}}, booktitle = {{Proc. Int. Symp. on Field-Programmable Custom Computing Machines (FCCM)}}, keywords = {{tet_topic_hpc}}, publisher = {{IEEE}}, title = {{{OpenCL-based FPGA Design to Accelerate the Nodal Discontinuous Galerkin Method for Unstructured Meshes}}}, doi = {{10.1109/FCCM.2018.00037}}, year = {{2018}}, } @inproceedings{1590, abstract = {{We present the submatrix method, a highly parallelizable method for the approximate calculation of inverse p-th roots of large sparse symmetric matrices which are required in different scientific applications. Following the idea of Approximate Computing, we allow imprecision in the final result in order to utilize the sparsity of the input matrix and to allow massively parallel execution. For an n x n matrix, the proposed algorithm allows to distribute the calculations over n nodes with only little communication overhead. The result matrix exhibits the same sparsity pattern as the input matrix, allowing for efficient reuse of allocated data structures. We evaluate the algorithm with respect to the error that it introduces into calculated results, as well as its performance and scalability. We demonstrate that the error is relatively limited for well-conditioned matrices and that results are still valuable for error-resilient applications like preconditioning even for ill-conditioned matrices. We discuss the execution time and scaling of the algorithm on a theoretical level and present a distributed implementation of the algorithm using MPI and OpenMP. We demonstrate the scalability of this implementation by running it on a high-performance compute cluster comprised of 1024 CPU cores, showing a speedup of 665x compared to single-threaded execution.}}, author = {{Lass, Michael and Mohr, Stephan and Wiebeler, Hendrik and Kühne, Thomas and Plessl, Christian}}, booktitle = {{Proc. Platform for Advanced Scientific Computing (PASC) Conference}}, isbn = {{978-1-4503-5891-0/18/07}}, keywords = {{approximate computing, linear algebra, matrix inversion, matrix p-th roots, numeric algorithm, parallel computing}}, location = {{Basel, Switzerland}}, publisher = {{ACM}}, title = {{{A Massively Parallel Algorithm for the Approximate Calculation of Inverse p-th Roots of Large Sparse Matrices}}}, doi = {{10.1145/3218176.3218231}}, year = {{2018}}, } @inproceedings{1204, author = {{Riebler, Heinrich and Vaz, Gavin Francis and Kenter, Tobias and Plessl, Christian}}, booktitle = {{Proc. ACM SIGPLAN Symposium on Principles and Practice of Parallel Programming (PPoPP)}}, isbn = {{9781450349826}}, keywords = {{htrop}}, publisher = {{ACM}}, title = {{{Automated Code Acceleration Targeting Heterogeneous OpenCL Devices}}}, doi = {{10.1145/3178487.3178534}}, year = {{2018}}, } @inproceedings{56157, author = {{Schulte, Carsten and Krüger, Jessica and Gödecke, Andreas and Schmidt, Ann-Katrin}}, booktitle = {{Proceedings of the 13th Workshop in Primary and Secondary Computing Education}}, publisher = {{ACM}}, title = {{{The computing repair cafe}}}, doi = {{10.1145/3265757.3265781}}, year = {{2018}}, } @inproceedings{56249, author = {{Fleischmann, Yael and Kempen, Leander and Mai, Tobias and Biehler, Rolf}}, booktitle = {{Hanse-Kolloquium zur Hochschuldidaktik der Mathematik}}, editor = {{Klinger, M. and Schüler-Meyer, A. and Wessel, L.}}, pages = {{101–116}}, publisher = {{WTM-Verlag}}, title = {{{Die online Lernmaterialien von studiVEMINT: Einsatzszenarien im Blended Learning Format in mathematischen Vorkursen}}}, year = {{2018}}, } @article{56254, author = {{Kempen, Leander and Biehler, Rolf}}, issn = {{2198-9745}}, journal = {{International Journal of Research in Undergraduate Mathematics Education}}, number = {{1}}, pages = {{27--55}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Pre-Service Teachers’ Benefits from an Inquiry-Based Transition-to-Proof Course with a Focus on Generic Proofs}}}, doi = {{10.1007/s40753-018-0082-9}}, volume = {{5}}, year = {{2018}}, } @book{56253, author = {{Hochmuth, Reinhard and Biehler, Rolf and Schaper, Niclas and Kuklinski, Christiane and Lankeit, Elisa and Leis, Elena and Liebendörfer, Michael and Schürmann, Mirko}}, publisher = {{Leibniz Universität Hannover}}, title = {{{Wirkung und Gelingensbedingungen von Unterstützungsmaßnahmen für mathmatikbezogenes Lernen in der Studieneingangsphase: Schlussbericht: Teilprojekt A der Leibniz Universität Hannover, Teilprojekte B und C der Universität Paderborn: Berichtszeitraum: 01.03. 2015-31.08. 2018}}}, year = {{2018}}, } @inbook{56349, author = {{Barzel, Bärbel and Biehler, Rolf and Blömeke, Sigrid and Brandtner, Regine and Bruns, Julia and Dohrmann, Christian and Kortenkamp, Ulrich and Lange, Thomas and Leuders, Timo and Rösken-Winter, Bettina and Scherer, Petra and Selter, Christoph}}, booktitle = {{Konzepte und Studien zur Hochschuldidaktik und Lehrerbildung Mathematik}}, isbn = {{9783658190279}}, issn = {{2197-8751}}, pages = {{7--40}}, publisher = {{Springer Fachmedien Wiesbaden}}, title = {{{Das Deutsche Zentrum für Lehrerbildung Mathematik – DZLM}}}, doi = {{10.1007/978-3-658-19028-6_2}}, year = {{2018}}, } @book{56354, editor = {{Biehler, Rolf and Budde, Lea and Frischemeier, Daniel and Heinemann, B. and Podworny, Susanne and Schulte, Carsten and Wassong, Thomas}}, publisher = {{Universitätsbibliothek Paderborn}}, title = {{{Paderborn symposium on data science education at school level 2017: The collected extended abstracts. Universitätsbibliothek Paderborn}}}, year = {{2018}}, } @article{56361, author = {{Biehler, Rolf and Frischemeier, Daniel and Podworny, Susanne}}, issn = {{1863-9690}}, journal = {{ZDM}}, number = {{7}}, pages = {{1237--1251}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Elementary preservice teachers’ reasoning about statistical modeling in a civic statistics context}}}, doi = {{10.1007/s11858-018-1001-x}}, volume = {{50}}, year = {{2018}}, } @article{56360, author = {{Biehler, Rolf and Frischemeier, Daniel and Podworny, Susanne}}, journal = {{Zeitschrift für Hochschulentwicklung}}, number = {{2}}, pages = {{169--182}}, title = {{{ Civic Engagement in Higher Education: A university course in civic statistics for mathematics preservice teachers - Civic Engagement in Higher Education: A university course in civic statistics for mathematics preservice teachers}}}, doi = {{10.3217/ZFHE-13-02/11}}, volume = {{13}}, year = {{2018}}, } @inproceedings{56351, author = {{Biehler, Rolf}}, booktitle = {{Looking back, looking forward. Proceedings of the Tenth International Conference on Teaching Statistics (ICOTS10, July 8–13), Kyoto, Japan. https://iase-web. org/icots/10/proceedings/pdfs/ICOTS10_1B1. pdf}}, title = {{{Design principles, realizations and uses of software supporting the learning and the doing of statistics: A reflection on developments since the late 1990s}}}, year = {{2018}}, } @inbook{56355, author = {{Biehler, Rolf and Fleischmann, Yael and Gold, Alexander}}, booktitle = {{Beiträge zum Mathematikunterricht 2018, Band I}}, pages = {{277--280}}, publisher = {{WTM-Verlag}}, title = {{{Konzepte für die Gestaltung von Online-Vorkursen für Mathematik und für ihre Integration in Blended-Learning-Szenarien}}}, year = {{2018}}, } @article{56362, author = {{Biehler, Rolf and Frischemeier, Daniel and Podworny, Susanne and Wassong, Thomas and Budde, Lea and Heinemann, B. and Schulte, Carsten}}, journal = {{Archives of Data Science, Series A}}, number = {{1}}, title = {{{Data Science and Big Data in Upper Secondary Schools: A Module to Build up First Components of Statistical Thinking in a Data Science Curriculum}}}, doi = {{10.5445/KSP/1000087327/28}}, volume = {{5}}, year = {{2018}}, } @book{56692, editor = {{Biehler, Rolf and Lange, Thomas and Leuders, Timo and Rösken-Winter, Bettina and Scherer, Petra and Selter, Christoph}}, isbn = {{9783658190279}}, issn = {{2197-8751}}, publisher = {{Springer Fachmedien Wiesbaden}}, title = {{{Mathematikfortbildungen professionalisieren}}}, doi = {{10.1007/978-3-658-19028-6}}, year = {{2018}}, } @article{56706, abstract = {{Group comparisons offer students opportunities to reason about many fundamental statistical concepts like center, variation, or distribution. When doing such activities using large, real datasets, technology becomes and essential tool for exploring the data. With its large variety of features and its user-friendly handling, TinkerPlotsTM --as a software for learners and teachers--can facilitate the process of comparing distributions. In this article we focus on eight preservice teachers´  reasoning when comparing groups with TinkerPlots. We present ideas on the design of a course to develop statistical reasoning with TinkerPlots, present a framework to rate learners´  performance when comparing groups with TinkerPlots, and present results of a laboratory study about preservice teachers´  reasoning when comparing groups with TinkerPlots. Findings suggest that the TinkerPlots tool and design of the course supported these preservice teachers´  reasoning and that more learning opportunities are needed to increase their group comparison elements´  repertoire and interpretation in context. First published May 2018 at Statistics Education Research Journal Archives}}, author = {{Frischemeier, Daniel and Biehler, Rolf}}, issn = {{1570-1824}}, journal = {{Statistics Education Research Journal}}, number = {{1}}, pages = {{35--60}}, publisher = {{International Association for Statistical Education}}, title = {{{Preservice teachers´ comparing groups with TinkerPlots - An exploratory video study}}}, doi = {{10.52041/serj.v17i1.175}}, volume = {{17}}, year = {{2018}}, }