@inproceedings{5632, abstract = {{Enduring doubts about the value of IS investments reveal that IS researchers have not fully managed to identify and to explain the economic benefits of IS. Three research tasks are essential requisites on the path towards addressing this criticism: the synthesis of knowledge, the identification of lack of knowledge, and the proposition of paths for closing knowledge gaps. This paper considers each of these tasks by a) synthesizing key research findings based on a comprehensive literature review, b) identifying and unfolding key limitations of current research, and c) applying a decision-theoretic perspective, which opens new horizons to IS business value research and shows paths for overcoming the limitations. The adoption of this perspective results in a decision-theoretic foundation of IS business value research and includes the proposition of a consistent terminology and a research model that frames further research.}}, author = {{Schryen, Guido and Bodenstein, Christian}}, booktitle = {{Proceedings of the 18th European Conference on Information Systems (ECIS 2010)}}, keywords = {{Decision theory, IT value, IS assessment, IS evaluation}}, title = {{{A decision-theoretic foundation of IS business value research}}}, year = {{2010}}, } @inproceedings{5643, abstract = {{Enduring doubts about the value of IS investments reveal that IS researchers have not fully managed to identify and to explain the economic benefits of IS. This paper assumes that literature reviews, which represent a powerful instrument for the identification and synthesis of knowledge, have not tapped their full potential to address this issue due to deficiencies in methodology. The analysis of 18 literature reviews published in pertinent academic outlets during the past 20 years shows such deficiencies. Two of the most critical weaknesses identified are (1) the lack of theory use in most reviews and (2) a weak linkage of reviews, resulting in little progress in theory and framework development. The systematic identification of these weaknesses and the extraction of promising methodological examples from past literature are the main contributions of this work, which supports the composition of more effective literature reviews in future research.}}, author = {{Schryen, Guido}}, booktitle = {{Proceedings of the First Scandinavian Conference on Information Systems (SCIS)}}, keywords = {{Literature review, Business value, Information systems, Methodology, Theory}}, title = {{{An Analysis of Literature Reviews on IS Business Value: How Deficiencies in Methodology and Theory Use Resulted in Limited Effectiveness}}}, year = {{2010}}, } @article{34887, abstract = {{Let d be a nonsquare positive integer. We give the value of the natural probability that the narrow ideal class groups of the quadratic fields ℚ(√d) and ℚ(√−d) have the same 4-ranks. }}, author = {{Fouvry, Étienne and Klüners, Jürgen}}, issn = {{1937-0652}}, journal = {{Algebra & Number Theory}}, keywords = {{Algebra and Number Theory}}, number = {{5}}, pages = {{493--508}}, publisher = {{Mathematical Sciences Publishers}}, title = {{{On the Spiegelungssatz for the 4-rank}}}, doi = {{10.2140/ant.2010.4.493}}, volume = {{4}}, year = {{2010}}, } @article{32519, abstract = {{Im vorliegenden Beitrag wird der Zusammenhang zwischen der Fähigkeit zur Perspektivenübernahme und sinnverstehendem Lesen dargestellt. Auf der Grundlage von Arbeiten zum Textverstehen sowie zu Perspektivenübernahme und Theory of Mind wurde ein positiver Zusammenhang zwischen Perspektivenübernahmefähigkeit und Textverstehensleistung erwartet. Diese Hypothese wurde an zwei Stichproben unterschiedlichen Alters geprüft: In der ersten Studie beantworteten 37 Vorschulkinder Fragen zu vorgelesenen Geschichten sowie Perspektivenübernahme-Aufgaben. Zwischen den Bereichen fand sich eine deutliche positive Korrelation, die bei Kontrolle der Intelligenz erhalten blieb. An der zweiten Studie nahmen 69 Grundschulkinder der dritten Jahrgangsstufe teil, die Texte lasen und Aufgaben dazu wie auch zur Perspektivenübernahme bearbeiteten. In dieser Stichprobe fand sich der erwartete Zusammenhang ausschließlich in der Teilgruppe der guten Leser. Er blieb bei Kontrolle der Intelligenz erhalten. Die Ergebnisse werden auch in Hinblick auf die Förderung der Lesekompetenz diskutiert.}}, author = {{Buhl, Heike M. and Möller, Franziska and Oebser, Manuela and Stein, Freia and Noack, Peter}}, journal = {{Diskurs Kindheits- und Jugendforschung}}, keywords = {{Textverstehen, Lesekompetenz, Perspektivenübernahme, Theory of Mind, Kindesalter}}, pages = {{75 -- 90}}, title = {{{Zusammenhänge zwischen der Fähigkeit zur Perspektivenübernahme und dem Textverstehen im Vor- und Grundschulalter}}}, volume = {{1}}, year = {{2009}}, } @article{34889, abstract = {{We prove that van Hoeij’s original algorithm to factor univariate polynomials over the rationals runs in polynomial time, as well as natural variants. In particular, our approach also yields polynomial time complexity results for bivariate polynomials over a finite field.}}, author = {{Belabas, Karim and van Hoeij, Mark and Klüners, Jürgen and Steel, Allan}}, issn = {{1246-7405}}, journal = {{Journal de Théorie des Nombres de Bordeaux}}, keywords = {{Algebra and Number Theory}}, number = {{1}}, pages = {{15--39}}, publisher = {{Cellule MathDoc/CEDRAM}}, title = {{{Factoring polynomials over global fields}}}, doi = {{10.5802/jtnb.655}}, volume = {{21}}, year = {{2009}}, } @inproceedings{9568, abstract = {{A simple pre-stress estimate method of Langevin transducers is studied. The measurement setup consists of a capacitor, an impedance converter and a voltmeter. Based on the piezoelectric equation and the basic circuit theory, the mathematical expression between the pre-stress and the voltage across the capacitor is derived. The pre-stress level can then be calculated out of the measurement of the capacitor voltage. In order to evaluate the precision of this method, a force washer is used to measure the pre-stress of the Langevin transducer. The result shows the pre-stress level obtained from this method is 30-40\% higher than the pre-stress level measured by the force washer. This method is simple and can be used to estimate the pre-stress of various Langevin transducers. The precision of this method can be raised if d33 is identified under different pre-stress levels.}}, author = {{Bo, Fu and Ting, Li and Hemsel, Tobias}}, booktitle = {{Piezoelectricity, Acoustic Waves, and Device Applications, 2008. SPAWDA 2008. Symposium on}}, keywords = {{capacitors, impedance convertors, piezoelectric transducers, stress analysis, Langevin transducers, basic circuit theory, capacitor, impedance converter, piezoelectric equation, pre-stress estimating method, voltmeter, Capacitors, Educational institutions, Equations, Force measurement, Impedance measurement, Manufacturing, Mechatronics, Piezoelectric transducers, Voltage, Voltmeters, Langevin transducer, capacitor, piezoelectric element, pre-stress}}, pages = {{324--327}}, title = {{{A simple pre-stress estimating method of langevin transducers}}}, doi = {{10.1109/SPAWDA.2008.4775801}}, year = {{2008}}, } @article{45431, author = {{Mahnken, Rolf}}, issn = {{0178-7675}}, journal = {{Computational Mechanics}}, keywords = {{Applied Mathematics, Computational Mathematics, Computational Theory and Mathematics, Mechanical Engineering, Ocean Engineering, Computational Mechanics}}, number = {{5}}, pages = {{408--425}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{A Newton-Multigrid algrithm for elasto-plastic/viscoplastic problems}}}, doi = {{10.1007/bf00350355}}, volume = {{15}}, year = {{2008}}, } @article{39947, author = {{Rösler, Margit}}, issn = {{0010-437X}}, journal = {{Compositio Mathematica}}, keywords = {{Algebra and Number Theory}}, number = {{03}}, pages = {{749--779}}, publisher = {{Wiley}}, title = {{{Bessel convolutions on matrix cones}}}, doi = {{10.1112/s0010437x06002594}}, volume = {{143}}, year = {{2007}}, } @article{34891, abstract = {{We study the asymptotics conjecture of Malle for dihedral groups Dℓ of order 2ℓ, where ℓ is an odd prime. We prove the expected lower bound for those groups. For the upper bounds we show that there is a connection to class groups of quadratic number fields. The asymptotic behavior of those class groups is predicted by the Cohen--Lenstra heuristics. Under the assumption of this heuristic we are able to prove the expected upper bounds. }}, author = {{Klüners, Jürgen}}, issn = {{1246-7405}}, journal = {{Journal de Théorie des Nombres de Bordeaux}}, keywords = {{Algebra and Number Theory}}, number = {{3}}, pages = {{607--615}}, publisher = {{Cellule MathDoc/CEDRAM}}, title = {{{Asymptotics of number fields and the Cohen–Lenstra heuristics}}}, doi = {{10.5802/jtnb.561}}, volume = {{18}}, year = {{2006}}, } @article{34892, abstract = {{We prove that the number of quartic S4--extensions of the rationals of given discriminant d is $O_\eps(d^{1/2+\eps})$ for all $\eps>0$. For a prime number p we derive that the dimension of the space of octahedral modular forms of weight 1 and conductor p or p² is bounded above by O(p¹/²log(p)²). }}, author = {{Klüners, Jürgen}}, issn = {{0065-1036}}, journal = {{Acta Arithmetica}}, keywords = {{Algebra and Number Theory}}, number = {{2}}, pages = {{185--194}}, publisher = {{Institute of Mathematics, Polish Academy of Sciences}}, title = {{{The number of S₄-fields with given discriminant}}}, doi = {{10.4064/aa122-2-3}}, volume = {{122}}, year = {{2006}}, } @article{34893, abstract = {{Let K be a global field and O be an order of K. We develop algorithms for the computation of the unit group of residue class rings for ideals O in . As an application we show how to compute the unit group and the Picard group of O provided that we are able to compute the unit group and class group of the maximal order O of K.}}, author = {{Klüners, Jürgen and Pauli, Sebastian}}, issn = {{0021-8693}}, journal = {{Journal of Algebra}}, keywords = {{Algebra and Number Theory}}, number = {{1}}, pages = {{47--64}}, publisher = {{Elsevier BV}}, title = {{{Computing residue class rings and Picard groups of orders}}}, doi = {{10.1016/j.jalgebra.2005.04.013}}, volume = {{292}}, year = {{2005}}, } @inproceedings{11931, abstract = {{The paper is concerned with binaural signal processing for a bimodal human-robot interface with hearing and vision. The two microphone signals are processed to obtain an enhanced single-channel input signal for the subsequent speech recognizer and to localize the acoustic source, an important information for establishing a natural human-robot communication. We utilize a robust adaptive algorithm for filter-and-sum beamforming (FSB) and extract speaker direction information from the resulting FIR filter coefficients. Further, particle filtering is applied which conducts a nonlinear Bayesian tracking of speaker movement. Good location accuracy can be achieved even in highly reverberant environments. The results obtained outperform the conventional generalized cross correlation (GCC) method.}}, author = {{Warsitz, Ernst and Haeb-Umbach, Reinhold}}, booktitle = {{IEEE Workshop on Multimedia Signal Processing (MMSP 2004)}}, keywords = {{bimodal human-robot interface, binaural signal processing, enhanced single-channel input signal, filter-and-sum beamforming, filtering theory, FIR filter coefficient, generalized cross correlation method, microphones, microphone signal, nonlinear Bayesian tracking, particle filtering, robust adaptive algorithm, robust speaker direction estimation, signal processing, speech enhancement, speech recognition, speech recognizer, user interfaces}}, pages = {{367--370}}, title = {{{Robust speaker direction estimation with particle filtering}}}, doi = {{10.1109/MMSP.2004.1436569}}, year = {{2004}}, } @inproceedings{39061, abstract = {{This article presents an approach, which combines theorem proving-based refinement with model checking for state based real-time systems. Our verification flow starts from UML state diagrams, which are translated to the formal B language and are model checked for real-time properties. By means of the B language and a B theorem prover, refined state diagrams are verified against their abstract representation. The approach is presented by means of the refinement of a digital echo cancellation unit.}}, author = {{Krupp, Alexander and Müller, Wolfgang and Oliver, Ian}}, booktitle = {{Proceedings of DATE’04 Designers' Forum}}, isbn = {{0-7695-2085-5}}, keywords = {{Echo cancellers, Logic, Unified modeling language, Automata, Data structures, Boolean functions, Electronic design automation and methodology, Prototypes, Specification languages, Constraint theory}}, title = {{{Formal Refinement and Model Checking of An Echo Cancellation Unit}}}, doi = {{10.1109/DATE.2004.1269214}}, year = {{2004}}, } @article{34896, abstract = {{We apply class field theory to the computation of the minimal discriminants for certain solvable groups. In particular, we apply our techniques to small Frobenius groups and all imprimitive degree 8 groups such that the corresponding fields have only a degree 2 and no degree 4 subfield.}}, author = {{Fieker, Claus and Klüners, Jürgen}}, issn = {{0022-314X}}, journal = {{Journal of Number Theory}}, keywords = {{Algebra and Number Theory}}, number = {{2}}, pages = {{318--337}}, publisher = {{Elsevier BV}}, title = {{{Minimal discriminants for fields with small Frobenius groups as Galois groups}}}, doi = {{10.1016/s0022-314x(02)00071-9}}, volume = {{99}}, year = {{2003}}, } @article{45423, author = {{Mahnken, Rolf}}, issn = {{1069-8299}}, journal = {{Communications in Numerical Methods in Engineering}}, keywords = {{Applied Mathematics, Computational Theory and Mathematics, General Engineering, Modeling and Simulation, Software}}, number = {{10}}, pages = {{745--754}}, publisher = {{Wiley}}, title = {{{Improved implementation of an algorithm for non-linear isotropic/kinematic hardening in elastoplasticity}}}, doi = {{10.1002/(sici)1099-0887(199910)15:10<745::aid-cnm288>3.0.co;2-r}}, volume = {{15}}, year = {{2002}}, } @article{45417, author = {{Döbert, C. and Mahnken, Rolf and Stein, E.}}, issn = {{0178-7675}}, journal = {{Computational Mechanics}}, keywords = {{Applied Mathematics, Computational Mathematics, Computational Theory and Mathematics, Mechanical Engineering, Ocean Engineering, Computational Mechanics}}, number = {{5}}, pages = {{456--467}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Numerical simulation of interface debonding with a combined damage/friction constitutive model}}}, doi = {{10.1007/s004660050493}}, volume = {{25}}, year = {{2002}}, } @article{45427, abstract = {{In this work a gradient‐based optimization method is applied in order to determine material parameters for a viscoplastic model with dynamic yield surface coupled to damage as presented in 1997. To this end a sensitivity analysis consistent with the integration scheme presented previously is performed in a systematic manner, both for strain and stress controlled experiments. The algorithm is tested in two numerical examples: first, simulated data are used, in order to re‐obtain parameters for the case of damage under monotonic loading. In the second example material parameters are obtained based on experimental data for lcf‐testing of an austenetic stainless steel, thus showing a very good agreement with respect to hardening, rate and damage effects.}}, author = {{Mahnken, Rolf and Johansson, Magnus and Runesson, Kenneth}}, issn = {{0264-4401}}, journal = {{Engineering Computations}}, keywords = {{Computational Theory and Mathematics, Computer Science Applications, General Engineering, Software}}, number = {{7}}, pages = {{925--955}}, publisher = {{Emerald}}, title = {{{Parameter estimation for a viscoplastic damage model using a gradient‐based optimization algorithm}}}, doi = {{10.1108/02644409810236920}}, volume = {{15}}, year = {{2002}}, } @article{34897, abstract = {{This paper announces the creation of a database for number fields. It describes the contents and the methods of access, indicates the origin of the polynomials, and formulates the aims of this collection of fields.}}, author = {{Klüners, Jürgen and Malle, Gunter}}, issn = {{1461-1570}}, journal = {{LMS Journal of Computation and Mathematics}}, keywords = {{Computational Theory and Mathematics, General Mathematics}}, pages = {{182--196}}, publisher = {{Wiley}}, title = {{{A Database for Field Extensions of the Rationals}}}, doi = {{10.1112/s1461157000000851}}, volume = {{4}}, year = {{2001}}, } @article{34900, abstract = {{We describe methods for the computation of Galois groups of univariate polynomials over the rationals which we have implemented up to degree 15. These methods are based on Stauduhar’s algorithm. All computations are done in unramified p -adic extensions. For imprimitive groups we give an improvement using subfields. In the primitive case we use known subgroups of the Galois group together with a combination of Stauduhar’s method and the absolute resolvent method.}}, author = {{Geissler, Katharina and Klüners, Jürgen}}, issn = {{0747-7171}}, journal = {{Journal of Symbolic Computation}}, keywords = {{Computational Mathematics, Algebra and Number Theory}}, number = {{6}}, pages = {{653--674}}, publisher = {{Elsevier BV}}, title = {{{Galois Group Computation for Rational Polynomials}}}, doi = {{10.1006/jsco.2000.0377}}, volume = {{30}}, year = {{2000}}, } @article{34901, abstract = {{Let L = K(α) be an Abelian extension of degree n of a number field K, given by the minimal polynomial of α over K. We describe an algorithm for computing the local Artin map associated with the extension L / K at a finite or infinite prime v of K. We apply this algorithm to decide if a nonzero a ∈ K is a norm from L, assuming that L / K is cyclic.}}, author = {{Acciaro, Vincenzo and Klüners, Jürgen}}, issn = {{0747-7171}}, journal = {{Journal of Symbolic Computation}}, keywords = {{Computational Mathematics, Algebra and Number Theory}}, number = {{3}}, pages = {{239--252}}, publisher = {{Elsevier BV}}, title = {{{Computing Local Artin Maps, and Solvability of Norm Equations}}}, doi = {{10.1006/jsco.2000.0361}}, volume = {{30}}, year = {{2000}}, }