TY - GEN AU - Bornemann, Tobias AU - Schipp, Adrian AU - Sureth-Sloane, Caren ID - 21407 TI - 2018/2019 Umfrage zur Steuerkomplexität in deutschen Finanzverwaltungen ER - TY - GEN AB - European regulation mandates public country-by-country reporting for banks and is expected to increase reputational costs in case of tax haven activities. We test whether the availability of additional public information on the locations of banks' subsidiaries reduces their tax haven presence. In a preliminary difference-in-difference analysis we find that indeed, tax haven presence in “Dot-Havens” has declined significantly after the introduction of mandatory public country-by-country reporting for European banks, as compared to the insurance industry which is not subject to this regulation. AU - Eberhartinger, Eva AU - Speitmann, Raffael AU - Sureth-Sloane, Caren ID - 21409 TI - Real Effects of Public Country-by-Country Reporting and the Firm Structure of European Banks VL - #2020-01 ER - TY - GEN AB - We analyze the impact of trust on bargaining behavior between auditor and auditee in a tax setting. We study the effect of interpersonal trust and trust in government on both taxpayer and tax auditor. In an experiment with variation in pairwise trust settings, we find evidence that both kinds of trust affect the bargaining behavior, albeit in different ways. While trust in government increases taxpayers’ tax offers, interpersonal trust may lead to more concessionary behavior of tax auditors moderated by trust in government. Our findings help tax authorities to shape programs to enhance compliance in an atmosphere of trust. AU - Eberhartinger, Eva AU - Speitmann, Raffael AU - Sureth-Sloane, Caren ID - 21410 TI - How Does Trust Affect Concessionary Behavior in Tax Bargaining? VL - No. 41 ER - TY - GEN AB - This study examines the visibility of the GAAP effective tax rate (ETR) in firms’ financial statements as a distinct disclosure choice. Applying a game-theory disclosure model for voluntary disclosure strategies of firms to a tax setting, we argue that firms face a trade-off in their ETR disclosure decisions. On the one hand, firms have an incentive to enhance their ETR disclosure when the ratio offers shareholders “favourable conditions”, for example in terms of higher expected after-tax cash-flows. On the other hand, the disclosure of a favourable low ETR could attract the attention of tax auditors and the public and ultimately result in disclosure costs. We empirically test disclosure behaviour by examining the relation between disclosure visibility and different ETR conditions that reflect different stakeholder specific costs and benefits. While we find that unfavourable ETR conditions are not highlighted, we observe higher disclosure visibility for favourable ETRs (smooth, close to the industry average, decreasing). Additional analyses reveal that this high visibility is characteristic of firm-years with only moderately decreasing ETRs at usual ETR levels, while extreme ETRs are not highlighted. Interestingly and in contrast to our main results, a subsample of family firms do not seem to highlight favourable ETRs. AU - Flagmeier, Vanessa AU - Müller, Jens AU - Sureth-Sloane, Caren ID - 21411 TI - When Do Firms Highlight Their Effective Tax Rate? VL - No. 37 ER - TY - GEN AU - Heile, Vanessa AU - Huber, Hans-Peter AU - Maiterth, Ralf AU - Sureth-Sloane, Caren ID - 21414 TI - Umfrage: Steuerliche Verwaltungskosten, steuerliche Corona-Soforthilfemaßnahmen und Investitionen in der Krise ER - TY - GEN AB - This article comprehensively reviews Australia’s corporate income tax complexity as faced by multinational corporations (MNCs) and compares it to the average of the remaining OECD countries. Building on unique survey data, I find that the Australian tax code is considerably more complex than the OECD average, which is mainly due to overly complex anti-avoidance legislation, such as regulations on transfer pricing, general anti-avoidance or controlled foreign corporations (CFC). In contrast, Australia’s tax framework, which covers processes and features such as tax law enactment or tax audits, is close to the OECD average. A more granular analysis yields further interesting insights. For example, excessive details in the tax code and the time between the announcement of a tax law change and its enactment turn out to be serious issues in Australia relative to the remaining OECD countries. AU - Hoppe, Thomas ID - 21416 TI - Tax Complexity in Australia - A Survey-Based Comparison to the OECD Average VL - No. 14 ER - TY - GEN AU - Hoppe, Thomas AU - Schanz, Deborah AU - Schipp, Adrian AU - Siegel, Felix AU - Sturm, Susann AU - Sureth-Sloane, Caren ID - 21417 TI - 2018 Global MNC Tax Complexity Survey ER - TY - GEN AB - This paper introduces an index that comprehensively measures the complexity of countries’ corporate income tax systems faced by multinational corporations. It builds on surveys of highly experienced tax consultants of the largest international tax services networks. The index, called the Tax Complexity Index (TCI), is composed of a tax code subindex covering tax regulations and a tax framework subindex covering tax processes and features. For a sample of 100 countries, we find that tax complexity varies considerably across countries, and tax code and framework complexity also vary within countries. Among others, tax complexity is strongly driven by the complexity of transfer pricing regulations in the tax code and tax audits in the tax framework. When analyzing the associations with other country characteristics, we identify different patterns. For example, with regard to GDP, we find a positive association with tax code complexity and a negative association with tax framework complexity, suggesting that highly economically developed countries tend to have more complex tax codes and less complex frameworks. Overall, our tax complexity measures can serve as valuable proxies in future research and supportive tools for a variety of firm decisions and national and international tax policy discussions. AU - Hoppe, Thomas AU - Schanz, Deborah AU - Sturm, Susann AU - Sureth-Sloane, Caren ID - 21418 TI - Measuring Tax Complexity Across Countries: A Survey Study on MNCs VL - No. 5 ER - TY - GEN AB - This paper analyzes the association between tax complexity and foreign direct investments (FDI) based on the newly developed Tax Complexity Index (TCI) and its components. For a sample of 15,607 new foreign subsidiaries, we find no association between total tax complexity, as proxied by the TCI, and the location probability. When we decompose the TCI into tax code complexity and tax framework complexity, we find opposing associations. Tax code complexity is positively related to the location probability, while tax framework complexity is negatively related to it. These associations are, for example, driven by the complexity of transfer pricing and loss offset regulations in the tax code and the dimensions guidance, audits, as well as filing and payments, in the tax framework. In additional analyses, we find that the associations are sensitive to certain characteristics, such as country-specific and firm-specific characteristics. For example, the positive tax code association diminishes when tax rates are high. Overall, we are the first to provide empirical evidence on potential cost-benefit tradeoffs of tax complexity for FDI and thereby enhance prior literature, which has primarily focused on the costs of tax complexity. AU - Hoppe, Thomas AU - Schanz, Deborah AU - Sturm, Susann AU - Sureth-Sloane, Caren AU - Voget, Johannes ID - 21419 TI - The Relation between Tax Complexity and Foreign Direct Investments: Evidence Across Countries VL - No. 13 ER - TY - JOUR AU - Sureth-Sloane, Caren ID - 21422 IS - 5 JF - AWV-Informationen TI - Steuerkomplexität als Standortfaktor. So komplex ist das Steuersystem in Deutschland ER - TY - CHAP AU - Hoppe, Julia Amelie AU - Johansson-Pajala, Rose-Marie AU - Gustafsson, Christine AU - Melkas, Helinä AU - Tusku, Outi AU - Pekkarinen, Satu AU - Hennala, Lea AU - Thommes, Kirsten ED - Haltaufderheide, Joschka ED - Hovemann, Johanna ED - Vollmann, Jochen ID - 17367 T2 - Aging between Participation and Simulation - Ethical Dimensions of Socially Assistive Technologies in elderly care TI - Assistive robots in care: Expectations and perceptions of older people ER - TY - JOUR AU - Chantakit, Teanchai AU - Schlickriede, Christian AU - Sain, Basudeb AU - Meyer, Fabian AU - Weiss, Thomas AU - Chattham, Nattaporn AU - Zentgraf, Thomas ID - 17390 IS - 9 JF - Photonics Research SN - 2327-9125 TI - All-dielectric silicon metalens for two-dimensional particle manipulation in optical tweezers VL - 8 ER - TY - JOUR AB - The development of renewable energies and smart mobility has profoundly impacted the future of the distribution grid. An increasing bidirectional energy flow stresses the assets of the distribution grid, especially medium voltage switchgear. This calls for improved maintenance strategies to prevent critical failures. Predictive maintenance, a maintenance strategy relying on current condition data of assets, serves as a guideline. Novel sensors covering thermal, mechanical, and partial discharge aspects of switchgear, enable continuous condition monitoring of some of the most critical assets of the distribution grid. Combined with machine learning algorithms, the demands put on the distribution grid by the energy and mobility revolutions can be handled. In this paper, we review the current state-of-the-art of all aspects of condition monitoring for medium voltage switchgear. Furthermore, we present an approach to develop a predictive maintenance system based on novel sensors and machine learning. We show how the existing medium voltage grid infrastructure can adapt these new needs on an economic scale. AU - Hoffmann, Martin W. AU - Wildermuth, Stephan AU - Gitzel, Ralf AU - Boyaci, Aydin AU - Gebhardt, Jörg AU - Kaul, Holger AU - Amihai, Ido AU - Forg, Bodo AU - Suriyah, Michael AU - Leibfried, Thomas AU - Stich, Volker AU - Hicking, Jan AU - Bremer, Martin AU - Kaminski, Lars AU - Beverungen, Daniel AU - zur Heiden, Philipp AU - Tornede, Tanja ID - 17426 JF - Sensors SN - 1424-8220 TI - Integration of Novel Sensors and Machine Learning for Predictive Maintenance in Medium Voltage Switchgear to Enable the Energy and Mobility Revolutions ER - TY - GEN AB - Syntactic annotation of corpora in the form of part-of-speech (POS) tags is a key requirement for both linguistic research and subsequent automated natural language processing (NLP) tasks. This problem is commonly tackled using machine learning methods, i.e., by training a POS tagger on a sufficiently large corpus of labeled data. While the problem of POS tagging can essentially be considered as solved for modern languages, historical corpora turn out to be much more difficult, especially due to the lack of native speakers and sparsity of training data. Moreover, most texts have no sentences as we know them today, nor a common orthography. These irregularities render the task of automated POS tagging more difficult and error-prone. Under these circumstances, instead of forcing the POS tagger to predict and commit to a single tag, it should be enabled to express its uncertainty. In this paper, we consider POS tagging within the framework of set-valued prediction, which allows the POS tagger to express its uncertainty via predicting a set of candidate POS tags instead of guessing a single one. The goal is to guarantee a high confidence that the correct POS tag is included while keeping the number of candidates small. In our experimental study, we find that extending state-of-the-art POS taggers to set-valued prediction yields more precise and robust taggings, especially for unknown words, i.e., words not occurring in the training data. AU - Heid, Stefan Helmut AU - Wever, Marcel Dominik AU - Hüllermeier, Eyke ID - 17605 T2 - Journal of Data Mining and Digital Humanities TI - Reliable Part-of-Speech Tagging of Historical Corpora through Set-Valued Prediction ER - TY - CONF AU - Haeb-Umbach, Reinhold ED - Böck, Ronald ED - Siegert, Ingo ED - Wendemuth, Andreas ID - 17763 KW - Poster SN - 978-3-959081-93-1 T2 - Studientexte zur Sprachkommunikation: Elektronische Sprachsignalverarbeitung 2020 TI - Sprachtechnologien für Digitale Assistenten ER - TY - JOUR AB - We numerically simulate multiple light scattering in discrete disordered media represented by large clusters of irregular non-absorbing particles. The packing density of clusters is 0.5. With such conditions diffuse scattering is significantly reduced and light transport follows propagation channels that are determined by the particle size and topology of the medium. This kind of localization produces coherent backscattering intensity surge and enhanced negative polarization branch if compared to lower density samples. AU - Grynko, Yevgen AU - Shkuratov, Yuriy AU - Förstner, Jens ID - 17803 JF - Journal of Quantitative Spectroscopy and Radiative Transfer KW - tet_topic_scattering SN - 0022-4073 TI - Light backscattering from large clusters of densely packed irregular particles VL - 255 ER - TY - CONF AU - Reinhold, Jannik AU - Frank, Maximilian AU - Koldewey, Christian AU - Dumitrescu, Roman AU - Buss, Eugen ID - 18876 T2 - Proceedings of the ISPIM Connects Bangkok – Partnering for an Innovative Community TI - In-depth Analysis of the Effects of Smart Services on Value Creation ER - TY - JOUR AU - Eke, Norbert Otto ID - 19153 IS - 1 JF - German Life and Letters (Special Issue: Herta Müller and the Currents of European History) TI - Der ‚Eigene Kalender‘ des Erinnerns: Die Wahrheit der erfundenen Erinnerung in Herta Müllers Romanen, Erzählungen und Essays VL - 73 ER - TY - CHAP AU - Reinhold, Jannik AU - Koldewey, Christian AU - Dumitrescu, Roman ED - Buchholz, Birgit ED - Bürger, Matthias ID - 20568 T2 - Der Geschäftsmodell-Toolguide TI - GEMINI-Modellierungssprache für Wertschöpfungssysteme ER - TY - CHAP AU - Koldewey, Christian AU - Reinhold, Jannik AU - Dumitrescu, Roman ED - Buchholz, Birgit ED - Bürger, Matthias ID - 20570 T2 - Der Geschäftsmodell-Toolguide TI - GEMINI-Geschäftsmodellmuster-Kartenset ER - TY - CHAP AU - Koldewey, Christian AU - Reinhold, Jannik AU - Dumitrescu, Roman ED - Buchholz, Birgit ED - Bürger, Matthias ID - 20571 T2 - Der Geschäftsmodell-Toolguide TI - Geschäftsmodellvalidierung ER - TY - CHAP AU - Koldewey, Christian AU - Reinhold, Jannik AU - Dumitrescu, Roman ED - Buchholz, Birgit ED - Bürger, Matthias ID - 20573 T2 - Der Geschäftsmodell-Toolguide TI - Geschäftsmodell-Roadmapping ER - TY - CONF AU - Boeddeker, Christoph AU - Nakatani, Tomohiro AU - Kinoshita, Keisuke AU - Haeb-Umbach, Reinhold ID - 20695 SN - 9781509066315 T2 - ICASSP 2020 - 2020 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) TI - Jointly Optimal Dereverberation and Beamforming ER - TY - CONF AU - Boeddeker, Christoph AU - Cord-Landwehr, Tobias AU - Heitkaemper, Jens AU - Zorila, Catalin AU - Hayakawa, Daichi AU - Li, Mohan AU - Liu, Min AU - Doddipatla, Rama AU - Haeb-Umbach, Reinhold ID - 20700 T2 - Proc. CHiME 2020 Workshop on Speech Processing in Everyday Environments TI - Towards a speaker diarization system for the CHiME 2020 dinner party transcription ER - TY - BOOK ED - Herzig, Bardo ED - Klar, Tilman-Mathies ED - Martin, Alexander ED - Meister, Dorothee ID - 20705 SN - 1424-3636 TI - Orientierungen in der digitalen Welt ER - TY - CONF AU - Camberg, Alan Adam AU - Tröster, Thomas ID - 20854 TI - A simplified method for the evaluation of the layer compression test using one 3D digital image correlation system and considering the material anisotropy by the equibiaxial Lankford parameter ER - TY - CONF AU - Camberg, Alan Adam AU - Erhart, Tobias AU - Tröster, Thomas ID - 20856 TI - Predicting fracture at non-isothermal forming conditions: A temperature dependent extension of the LS-DYNA GISSMO fracture indicator framework ER - TY - CONF AB - Augmented Reality (AR) has recently found high attention in mobile shopping apps such as in domains like furniture or decoration. Here, the developers of the apps focus on the positioning of atomic 3D objects in the physical environment. With this focus, they neglect the configuration of multi-faceted 3D object composition according to the user needs and environmental constraints. To tackle these challenges, we present a model-based approach to support AR-assisted product con-figuration based on the concept of Dynamic Software Product Lines. Our approach splits products (e.g. table) into parts (e.g. tabletop, ta-ble legs, funnier) with their 3D objects and additional information (e.g. name, price). The possible products, which can be configured out of these parts, are stored in a feature model. At runtime, this feature model can be used to configure 3D object compositions out of the product parts and adapt to user needs and environmental constraints. The benefits of this approach are demonstrated by a case study of configuring modular kitchens with the help of a prototypical mobile-based implementation. AU - Gottschalk, Sebastian AU - Yigitbas, Enes AU - Schmidt, Eugen AU - Engels, Gregor ED - Bernhaupt, Regina ED - Ardito, Carmelo ED - Sauer, Stefan ID - 18249 KW - Product Configuration KW - Augmented Reality KW - Runtime Adaptation KW - Dynamic Software Product Lines T2 - Human-Centered Software Engineering. HCSE 2020 TI - Model-based Product Configuration in Augmented Reality Applications VL - 12481 ER - TY - GEN AU - Schürmann, Patrick ID - 18637 TI - A Group Signature Scheme from Flexible Public Key Signatures and Structure-Preserving Signatures on Equivalence Classes ER - TY - JOUR AB - Many dimensionality and model reduction techniques rely on estimating dominant eigenfunctions of associated dynamical operators from data. Important examples include the Koopman operator and its generator, but also the Schrödinger operator. We propose a kernel-based method for the approximation of differential operators in reproducing kernel Hilbert spaces and show how eigenfunctions can be estimated by solving auxiliary matrix eigenvalue problems. The resulting algorithms are applied to molecular dynamics and quantum chemistry examples. Furthermore, we exploit that, under certain conditions, the Schrödinger operator can be transformed into a Kolmogorov backward operator corresponding to a drift-diffusion process and vice versa. This allows us to apply methods developed for the analysis of high-dimensional stochastic differential equations to quantum mechanical systems. AU - Klus, Stefan AU - Nüske, Feliks AU - Hamzi, Boumediene ID - 21819 JF - Entropy SN - 1099-4300 TI - Kernel-Based Approximation of the Koopman Generator and Schrödinger Operator ER - TY - CONF AU - Bobolz, Jan AU - Eidens, Fabian AU - Krenn, Stephan AU - Slamanig, Daniel AU - Striecks, Christoph ID - 16487 T2 - Proceedings of the 15th ACM Asia Conference on Computer and Communications Security (ASIA CCS ’20), TI - Privacy-Preserving Incentive Systems with Highly Efficient Point-Collection ER - TY - JOUR AU - Sain, Basudeb AU - Zentgraf, Thomas ID - 16839 JF - Light: Science & Applications SN - 2047-7538 TI - Metasurfaces help lasers to mode-lock VL - 9 ER - TY - JOUR AU - Zhou, Hongqiang AU - Sain, Basudeb AU - Wang, Yongtian AU - Schlickriede, Christian AU - Zhao, Ruizhe AU - Zhang, Xue AU - Wei, Qunshuo AU - Li, Xiaowei AU - Huang, Lingling AU - Zentgraf, Thomas ID - 16931 IS - 5 JF - ACS Nano SN - 1936-0851 TI - Polarization-Encrypted Orbital Angular Momentum Multiplexed Metasurface Holography VL - 14 ER - TY - CONF AB - The continuous innovation of its business models is an important task for a company to stay competitive. During this process, the company has to validate various hypotheses about its business models by adapting to uncertain and changing customer needs effectively and efficiently. This adaptation, in turn, can be supported by the concept of Software Product Lines (SPLs). SPLs reduce the time to market by deriving products for customers with changing requirements using a common set of features, structured as a feature model. Analogously, we support the process of business model adaptation by applying the engineering process of SPLs to the structure of the Business Model Canvas (BMC). We call this concept a Business Model Decision Line (BMDL). The BMDL matches business domain knowledge in the form of a feature model with customer needs to derive hypotheses about the business model together with experiments for validation. Our approach is effective by providing a comprehensive overview of possible business model adaptations and efficient by reusing experiments for different hypotheses. We implement our approach in a tool and illustrate the usefulness with an example of developing business models for a mobile application. AU - Gottschalk, Sebastian AU - Rittmeier, Florian AU - Engels, Gregor ID - 16933 KW - Business Model Decision Line KW - Business Model Adaptation KW - Hypothesis-driven Adaptation KW - Software Product Line KW - Feature Model T2 - Proceedings of the 22nd IEEE International Conference on Business Informatics TI - Hypothesis-driven Adaptation of Business Models based on Product Line Engineering ER - TY - CONF AB - To build successful products, the developers have to adapt their product features and business models to uncertain customer needs. This adaptation is part of the research discipline of Hypotheses Engineering (HE) where customer needs can be seen as hypotheses that need to be tested iteratively by conducting experiments together with the customer. So far, modeling support and associated traceability of this iterative process are missing. Both, in turn, are important to document the adaptation to the customer needs and identify experiments that provide most evidence to the customer needs. To target this issue, we introduce a model-based HE approach with a twofold contribution: First, we develop a modeling language that models hypotheses and experiments as interrelated hierarchies together with a mapping between them. While the hypotheses are labeled with a score level of their current evidence, the experiments are labeled with a score level of maximum evidence that can be achieved during conduction. Second, we provide an iterative process to determine experiments that offer the most evidence improvement to the modeled hypotheses. We illustrate the usefulness of the approach with an example of testing the business model of a mobile application. AU - Gottschalk, Sebastian AU - Yigitbas, Enes AU - Engels, Gregor ED - Shishkov, Boris ID - 16934 KW - Hypothesis Engineering KW - Model-based KW - Customer Need Adaptation KW - Business Model KW - Product Features T2 - Business Modeling and Software Design TI - Model-based Hypothesis Engineering for Supporting Adaptation to Uncertain Customer Needs VL - 391 ER - TY - CONF AU - Triebus, Marcel AU - Tröster, Thomas ID - 16939 T2 - Proceedings 4th International Conference Hybrid Materials & Structures TI - A Holistic Approach to Optimization-Based Design of Hybrid Materials ER - TY - GEN AB - The scientific impact of research papers is multi-dimensional and can be determined quantitatively by means of citation analysis and qualitatively by means of content analysis. Accounting for the widely acknowledged limitations of pure citation analysis, we adopt a knowledge-based perspective on scientific impact to develop a methodology for content-based citation analysis which allows determining how papers have enabled knowledge development in subsequent research (knowledge impact). As knowledge development differs between research genres, we develop a new knowledgebased citation analysis methodology for the genre of standalone literature reviews (LRs). We apply the suggested methodology to the IS business value domain by manually coding 22 LRs and 1,228 citing papers (CPs) and show that the results challenge the assumption that citations indicate knowledge impact. We derive implications for distinguishing knowledge impact from citation impact in the LR genre. Finally, we develop recommendations for authors of LRs, scientific evaluation committees and editorial boards of journals how to apply and benefit from the suggested methodology, and we discuss its efficiency and automatization. AU - Schryen, Guido AU - Wagner, Gerit AU - Benlian, Alexander ID - 17019 KW - Scientific impact KW - knowledge impact KW - content-based citation analysis KW - methodology TI - Distinguishing Knowledge Impact from Citation Impact: A Methodology for Analysing Knowledge Impact for the Literature Review Genre ER - TY - CONF AB - Understanding a new literature corpus can be a grueling experience for junior scholars. Nevertheless, corresponding guidelines have not been updated for decades. We contend that the traditional strategy of skimming all papers and reading selected papers afterwards needs to be revised. Therefore, we design a new strategy that guides the overall exploratory process by prioritizing influential papers for initial reading, followed by skimming the remaining papers. Consistent with schemata theory, starting with in-depth reading allows readers to acquire more substantial prior content schemata, which are representa-tive for the literature corpus and useful in the following skimming process. To this end, we develop a prototype that identifies the influential papers from a set of PDFs, which is illustrated in a case study in the IT business value domain. With the new strategy, we envision a more efficient process of exploring unknown literature corpora. AU - Wagner, Gerit AU - Empl, Philipp AU - Schryen, Guido ID - 17055 KW - Reading and skimming KW - Exploring literature KW - Review methodology KW - Design science research KW - Schemata theory T2 - 28th European Conference on Information Systems (ECIS 2020) TI - Designing a Novel Strategy for Exploring Literature Corpora ER - TY - CONF AU - Dreiling, Dmitrij AU - Itner, Dominik Thor AU - Feldmann, Nadine AU - Gravenkamp, Hauke AU - Henning, Bernd ID - 17089 TI - Increasing the sensitivity in the determination of material parameters by using arbitrary loads in ultrasonic transmission measurements ER - TY - JOUR AU - Schryen, Guido ID - 15414 IS - 9 JF - Communications of the ACM TI - Integrating Management Science into the HPC Research Ecosystem VL - 63 ER - TY - CONF AU - Claes, Leander AU - Baumhögger, Elmar AU - Rüther, Torben AU - Gierse, Jan AU - Tröster, Thomas AU - Henning, Bernd ID - 15490 T2 - Fortschritte der Akustik - DAGA 2020 TI - Reduction of systematic measurement deviation in acoustic absorption measurement systems ER - TY - JOUR AB - This interview is part of the special issue (01/2020) on “High Performance Business Computing” to be published in the journal Business & Information Systems Engineering. The interviewee Utz-Uwe Haus is Senior Research Engineer @ CRAY European Research Lab (CERL)). A bio of him is included at the end of the interview. AU - Schryen, Guido AU - Kliewer, Natalia AU - Fink, Andreas ID - 15513 IS - 01/2020 JF - Business & Information Systems Engineering TI - Interview with Utz-Uwe Haus on “High Performance Computing in Economic Environments: Opportunities and Challenges" VL - 62 ER - TY - JOUR AU - Schryen, Guido ID - 15022 IS - 1 JF - European Journal of Operational Research TI - Parallel computational optimization in operations research: A new integrative framework, literature review and research directions VL - 287 ER - TY - JOUR AB - Nonlinear Pancharatnam–Berry phase metasurfaces facilitate the nontrivial phase modulation for frequency conversion processes by leveraging photon‐spin dependent nonlinear geometric‐phases. However, plasmonic metasurfaces show some severe limitation for nonlinear frequency conversion due to the intrinsic high ohmic loss and low damage threshold of plasmonic nanostructures. Here, the nonlinear geometric‐phases associated with the third‐harmonic generation process occurring in all‐dielectric metasurfaces is studied systematically, which are composed of silicon nanofins with different in‐plane rotational symmetries. It is found that the wave coupling among different field components of the resonant fundamental field gives rise to the appearance of different nonlinear geometric‐phases of the generated third‐harmonic signals. The experimental observations of the nonlinear beam steering and nonlinear holography realized in this work by all‐dielectric geometric‐phase metasurfaces are well explained with the developed theory. This work offers a new physical picture to understand the nonlinear optical process occurring at nanoscale dielectric resonators and will help in the design of nonlinear metasurfaces with tailored phase properties. AU - Liu, Bingyi AU - Sain, Basudeb AU - Reineke, Bernhard AU - Zhao, Ruizhe AU - Meier, Cedrik AU - Huang, Lingling AU - Jiang, Yongyuan AU - Zentgraf, Thomas ID - 16197 IS - 9 JF - Advanced Optical Materials SN - 2195-1071 TI - Nonlinear Wavefront Control by Geometric-Phase Dielectric Metasurfaces: Influence of Mode Field and Rotational Symmetry VL - 8 ER - TY - CONF AB - Network function virtualization (NFV) proposes to replace physical middleboxes with more flexible virtual network functions (VNFs). To dynamically adjust to everchanging traffic demands, VNFs have to be instantiated and their allocated resources have to be adjusted on demand. Deciding the amount of allocated resources is non-trivial. Existing optimization approaches often assume fixed resource requirements for each VNF instance. However, this can easily lead to either waste of resources or bad service quality if too many or too few resources are allocated. To solve this problem, we train machine learning models on real VNF data, containing measurements of performance and resource requirements. For each VNF, the trained models can then accurately predict the required resources to handle a certain traffic load. We integrate these machine learning models into an algorithm for joint VNF scaling and placement and evaluate their impact on resulting VNF placements. Our evaluation based on real-world data shows that using suitable machine learning models effectively avoids over- and underallocation of resources, leading to up to 12 times lower resource consumption and better service quality with up to 4.5 times lower total delay than using standard fixed resource allocation. AU - Schneider, Stefan Balthasar AU - Satheeschandran, Narayanan Puthenpurayil AU - Peuster, Manuel AU - Karl, Holger ID - 16219 T2 - IEEE Conference on Network Softwarization (NetSoft) TI - Machine Learning for Dynamic Resource Allocation in Network Function Virtualization ER - TY - JOUR AB - Timing plays a crucial role in the context of information security investments. We regard timing in two dimensions, namely the time of announcement in relation to the time of investment and the time of announcement in relation to the time of a fundamental security incident. The financial value of information security investments is assessed by examining the relationship between the investment announcements and their stock market reaction focusing on the two time dimensions. Using an event study methodology, we found that both dimensions influence the stock market return of the investing organization. Our results indicate that (1) after fundamental security incidents in a given industry, the stock price will react more positively to a firm’s announcement of actual information security investments than to announcements of the intention to invest; (2) the stock price will react more positively to a firm’s announcements of the intention to invest after the fundamental security incident compared to before; and (3) the stock price will react more positively to a firm’s announcements of actual information security investments after the fundamental security incident compared to before. Overall, the lowest abnormal return can be expected when the intention to invest is announced before a fundamental information security incident and the highest return when actual investing after a fundamental information security incident in the respective industry. AU - Szubartowicz, Eva AU - Schryen, Guido ID - 16249 IS - 1 JF - Journal of Information System Security KW - Event Study KW - Information Security KW - Investment Announcements KW - Stock Price Reaction KW - Value of Information Security Investments TI - Timing in Information Security: An Event Study on the Impact of Information Security Investment Announcements VL - 16 ER - TY - CONF AB - To decide in which part of town to open stores, high street retailers consult statistical data on customers and cities, but they cannot analyze their customers’ shopping behavior and geospatial features of a city due to missing data. While previous research has proposed recommendation systems and decision aids that address this type of decision problem – including factory location and assortment planning – there currently is no design knowledge available to prescribe the design of city center area recommendation systems (CCARS). We set out to design a software prototype considering local customers’ shopping interests and geospatial data on their shopping trips for retail site selection. With real data on 500 customers and 1,100 shopping trips, we demonstrate and evaluate our IT artifact. Our results illustrate how retailers and public town center managers can use CCARS for spatial location selection, growing retailers’ profits and a city center’s attractiveness for its citizens. AU - zur Heiden, Philipp AU - Berendes, Carsten Ingo AU - Beverungen, Daniel ID - 16285 KW - Town Center Management KW - High Street Retail KW - Recommender Systems KW - Geospatial Recommendations KW - Design Science Research T2 - Proceedings of the 15th International Conference on Wirtschaftsinformatik TI - Designing City Center Area Recommendation Systems ER - TY - JOUR AB - The control of complex systems is of critical importance in many branches of science, engineering, and industry, many of which are governed by nonlinear partial differential equations. Controlling an unsteady fluid flow is particularly important, as flow control is a key enabler for technologies in energy (e.g., wind, tidal, and combustion), transportation (e.g., planes, trains, and automobiles), security (e.g., tracking airborne contamination), and health (e.g., artificial hearts and artificial respiration). However, the high-dimensional, nonlinear, and multi-scale dynamics make real-time feedback control infeasible. Fortunately, these high- dimensional systems exhibit dominant, low-dimensional patterns of activity that can be exploited for effective control in the sense that knowledge of the entire state of a system is not required. Advances in machine learning have the potential to revolutionize flow control given its ability to extract principled, low-rank feature spaces characterizing such complex systems.We present a novel deep learning modelpredictive control framework that exploits low-rank features of the flow in order to achieve considerable improvements to control performance. Instead of predicting the entire fluid state, we use a recurrent neural network (RNN) to accurately predict the control relevant quantities of the system, which are then embedded into an MPC framework to construct a feedback loop. In order to lower the data requirements and to improve the prediction accuracy and thus the control performance, incoming sensor data are used to update the RNN online. The results are validated using varying fluid flow examples of increasing complexity. AU - Bieker, Katharina AU - Peitz, Sebastian AU - Brunton, Steven L. AU - Kutz, J. Nathan AU - Dellnitz, Michael ID - 16290 JF - Theoretical and Computational Fluid Dynamics SN - 0935-4964 TI - Deep model predictive flow control with limited sensor data and online learning VL - 34 ER - TY - GEN AB - We study the structure of power networks in consideration of local protests against certain power lines (’not-in-my-backyard’). An application of a network formation game is used to determine whether or not such protests arise. We examine the existence of stable networks and their characteristics, when no player wants to make an alteration. Stability within this game is only reached if each player is sufficiently connected to a power source but is not linked to more players than necessary. In addition we introduce an algorithm that creates a stable network. AU - Block, Lukas ID - 23568 KW - Network formation KW - NIMBY KW - Power networks KW - Nash stability TI - Network formation with NIMBY constraints ER - TY - GEN AU - Ficara, Elena AU - d'Agostini, Franca ID - 30180 T2 - La Stampa TI - Perché celebrare Hegel? La sua dialettica è un brand, il suo pensiero una febbre benefica ER -