@inproceedings{KoenningHeinrichLeyhetal., author = {K{\"o}nning, Michael and Heinrich, Kai and Leyh, Christian and Westner, Markus}, title = {A quantitative analysis of culture-induced differences in pivotal IT outsourcing contract features}, series = {Proceedings of the 27th European Conference on Information Systems (ECIS 2019): Stockholm \& Uppsala, Sweden, June 8-14}, booktitle = {Proceedings of the 27th European Conference on Information Systems (ECIS 2019): Stockholm \& Uppsala, Sweden, June 8-14}, pages = {1 -- 15}, abstract = {More than 30 years after its first implementation, IT outsourcing (ITO) is unanimously considered a critical component of corporate strategy for private and public institutions alike. While implementations of ITO around the world share some common characteristics like typical reasons for outsourcing, key success factors, or dimensions along which they can be classified, extant research also points to regional differences. However, research on this topic, specifically regarding pivotal contract features like contract value, contract length, or pricing methods, is still in its infancy, and quantitative analyses on the subject are particularly scarce. We address this research gap by analyzing data on 14,917 ITO contracts closed between 2007 and 2017 through the lens of cultural regions and three statistical methods. The contribution of our paper is threefold. First, our descriptive analysis points to globally decreasing contract lengths and contract values, confirming previous studies and practice reports. Second, an ANOVA with independent post-hoc testing provides quantitative supportfor the degree of dissimilarity among individual regions in pivotal ITO contract features. Finally, our quantitative replication of a previous study identifies culture-induced regional differences between USA and Japan regarding the effect of influence factors on ITO contract features.}, subject = {Betriebliches Informationssytem}, language = {en} } @article{WestnerStrahringer, author = {Westner, Markus and Strahringer, Susanne}, title = {Determinants of success in IS offshoring projects}, series = {Information \& Management}, volume = {47}, journal = {Information \& Management}, number = {5-6}, pages = {291 -- 299}, abstract = {High labor cost in western countries allows cost savings by companies engaging in IS offshoring. However, studies worldwide indicate that a large number of companies that engaged in IS offshoring are not satisfied with the outcome. Our study examined the determinants of IS offshore project success: We developed a model and empirically tested it with data collected from 304 experts who reported on projects offshored from Germany to a wide range of near and distant countries. The model posited a direct effect of offshoring expertise and trust in offshore service provider (OSP) on success, as well as an indirect effect mediated by project suitability, knowledge transfer, and liaison quality. An analysis using partial least squares (PLSs) provided significant support for almost all these relationships. However, it showed that offshoring expertise played a minor role in explaining success and the mediating constructs. Trust in OSP had a small direct effect on success and a medium to large effect on the mediating constructs. Project suitability, knowledge transfer, and liaison quality all had small direct effects on success.}, subject = {Betriebliches Informationssystem}, language = {en} } @article{WestnerStrahringer, author = {Westner, Markus and Strahringer, Susanne}, title = {The current state of IS offshoring in Germany}, series = {Journal of Information Technology Management}, volume = {21}, journal = {Journal of Information Technology Management}, number = {1}, pages = {49 -- 70}, abstract = {This paper empirically examines the current state of the IS offshoring phenomenon in Germany regarding project characteristics and success patterns. Relying on a sample of 304 projects conducted at various industry sectors and companies, results show that IS offshoring primarily occurs in sectors Telecommunications and IT at large corporations. Cost reduction is the main reason for going offshore and offshore projects are executed as part of a larger program at companies. Noticeably, most projects are delivered from India. Additionally, neither captive offshoring nor offshore outsourcing dominates as a de-livery option. Comparing different project subgroups regarding project success, the results reveal that projects delivered by an internal or partially owned service provider are more successful. Other project characteristics such as a project's embedded-ness in a larger offshoring program, a project's size, or a project's offshoring degree in terms of relatively offshored labor hours show few significant differences. The paper addresses the paucity of empirical research on the current state of the IS offshoring phenomenon in Germany.}, subject = {Betriebliches Informationssystem}, language = {en} } @article{WestnerStrahringer, author = {Westner, Markus and Strahringer, Susanne}, title = {Evaluation criteria for selecting offshoring candidates}, series = {Journal of Information Technology Management}, volume = {19}, journal = {Journal of Information Technology Management}, number = {4}, pages = {16 -- 34}, abstract = {The identification of suitable applications or projects is a main initial step in any software development or maintenance related IS offshoring arrangement. This paper examines evaluation criteria and their importance for selecting application or project candidates for offshoring. Based on a literature analysis and interviews with 47 experts from 36 different German companies describing 64 case examples, we find that in contrast to the literature, "size", "codification", and "language" are perceived as important selection criteria by experts. Case examples additionally show that "business specificity" seems to be a main reason for application or project failures, that "business criticality" appears to be less important than suggested by the literature, and that adequate "size" might be a necessary prerequisite, but seems not to be a sufficient criterion for an application's or project's suitability for offshoring. These differences in comparison to findings from the literature may be explained by cultural and language differences.}, subject = {Betriebliches Informationssystem}, language = {en} } @inproceedings{WulfStrahringerWestner, author = {Wulf, Frederik and Strahringer, Susanne and Westner, Markus}, title = {Information security risks, benefits, and mitigation measures in cloud sourcing}, series = {Proceedings of the IEEE 21th Conference on Business Informatics (CBI): 2019, Moscow, Russia}, booktitle = {Proceedings of the IEEE 21th Conference on Business Informatics (CBI): 2019, Moscow, Russia}, pages = {258 -- 267}, abstract = {This paper develops a categorization of cloud security risks, elaborates how they impact information security, and discusses potential security benefits from cloud sourcing. This review integrates the literature on information systems and computer science to summarize managerial and technological mitigation measures that enhance cloud security. The analysis uncovers gaps regarding the empirical investigation of security considerations in the corporate decision-making process. Specifically, the micro level of how security comes into play in the decision-making process and whether mitigation measures proposed by scholars are practically feasible requires further investigation. Furthermore, the macro level, how stakeholders perceive cloud sourcing, is not yet well understood.}, subject = {Cloud Computing}, language = {en} } @inproceedings{BaryWestnerStrahringer, author = {Bary, Benedikt von and Westner, Markus and Strahringer, Susanne}, title = {Do researchers investigate what practitioners deem relevant?}, series = {Proceedings of the 20th IEEE International Conference on Business Informatics (IEEE CBI 2018): Vienna, Austria, 11-14 July}, booktitle = {Proceedings of the 20th IEEE International Conference on Business Informatics (IEEE CBI 2018): Vienna, Austria, 11-14 July}, doi = {10.1109/CBI.2018.00014}, pages = {40 -- 49}, abstract = {There is a common understanding amongst academics that information systems (IS) research sometimes has limited relevance for practitioners. This can be explained by the fact that research lags behind the fast moving IS environment, has limited practical applicability and is hard to access. We have focused on the research area of IS backsourcing, and analyzed practitioner literature to increase our understanding of topics of interest for practitioners, to determine a potential gap between academic and practitioner literature, and to identify future research directions in this field. We observed that most publications are either news or background articles, focusing on describing backsourcing cases. Additionally, we identified four recurring themes, namely reasons for backsourcing, presentation of survey results, discussion of industry trends, and backsourcing success stories. The main reasons identified to trigger backsourcing decisions are cost savings, quality improvements, and increasing control and flexibility. By comparing our findings with academic literature on IS backsourcing, we conclude that generally both literature types cover similar topics. However, researchers have a more formulative or interpretive focus than the often descriptive practitioner literature. Academic literature also examines a broader range of topics, while practitioner literature has a narrower focus. Additionally, we observe one difference regarding applied terminology: while researchers employ the term backsourcing, practitioners mostly use back in-house or insourcing. Our paper contributes to facilitating the exchange between academics and practitioners, presents topics to consider when aiming to increase practical relevance and provides researchers with concrete directions for future research within the field of IS backsourcing.}, subject = {Betriebliches Informationssystem}, language = {en} } @inproceedings{KobusWestner, author = {Kobus, J{\"o}rn and Westner, Markus}, title = {Ranking-type delphi studies in IS research}, series = {Proceedings of the 9th IADIS International Conference Information Systems, Vilamoura, Portugal, 9-11 April}, booktitle = {Proceedings of the 9th IADIS International Conference Information Systems, Vilamoura, Portugal, 9-11 April}, pages = {28 -- 38}, abstract = {Ranking-type Delphi is a frequently used method in IS research. However, besides several studies investigating a rigorous application of ranking-type Delphi as a research method, a comprehensive and precise step-by-step guide on how to conduct a rigorous ranking-type Delphi study in IS research is currently missing. In addition, a common critic of Delphi studies in general is that it is unclear if there is indeed authentic consensus of the panelists, or if panelists only agree because of other reasons (e.g. acquiescence bias or tiredness to disagreement after several rounds). This also applies to ranking-type Delphi studies. Therefore, this study aims to (1) Provide a rigorous step-by-step guide to conduct ranking-type Delphi studies through synthesizing results of existing research and (2) Offer an analytical extension to the ranking-type Delphi method by introducing Best/Worst Scaling, which originated in Marketing and Consumer Behavior research. A guiding example is introduced to increase comprehensibility of the proposals. Future research needs to validate the step-by-step guide in an empirical setting as well as test the suitability of Best/Worst Scaling within described research contexts.}, subject = {Delphi-Technik}, language = {en} } @inproceedings{WestnerSkeltonTinat, author = {Westner, Markus and Skelton, David and Tinat, Johannes}, title = {Enhancing students' IS offshoring capabilities}, series = {Proceedings of the 7th Annual Conference of Computing and Information Technology Research and Education New Zealand (CITRENZ 2016), Wellington, New Zealand, July 11-13}, booktitle = {Proceedings of the 7th Annual Conference of Computing and Information Technology Research and Education New Zealand (CITRENZ 2016), Wellington, New Zealand, July 11-13}, pages = {9}, abstract = {An appreciation of globalisation issues by information systems (IS) graduates is a growing requirement of organisations with global reach. This paper discusses the planning of a joint course to be delivered online and face to face by two lecturers representing two tertiary institutes in Germany and New Zealand respectively. The IS offshoring content of the course is relatively unique and aspects of globalisation will be demonstrated through the dual country delivery of the course. The two lecturers involved have spent time lecturing and studying in their global partner's country and tertiary institutes and so this joint delivery method is likely to also strengthen cultural ties between the two participating institutions including the students involved. Further research goals and issues are discussed for post-delivery of this dual country blended course. This paper provides a basis for this concept to be evaluated in further research.}, subject = {Informatikstudium}, language = {en} } @inproceedings{KobusWestnerStrahringer, author = {Kobus, J{\"o}rn and Westner, Markus and Strahringer, Susanne}, title = {Lean Management of IT Organizations}, series = {Proceedings of the 37th International Conference on Information Systems (ICIS 2016), Dublin,}, booktitle = {Proceedings of the 37th International Conference on Information Systems (ICIS 2016), Dublin,}, pages = {1 -- 12}, abstract = {Lean Management has been successfully implemented in production organizations since several decades. The study at hand investigates the implementation of Lean Management to IT organizations (Lean IT). The study offers three contributions: First, it explains on a conceptual level how Lean Management can be transferred from production to IT organizations (philosophy, principles, tools). Second, it provides a theoretical perspective on why Lean IT can be beneficial for IT organizations (IT Slack theory). Third, it provides insights to the stated research questions (three benefits and three propositions) from an initial case study of an internal IT service provider for a large international insurance company (> US\$25 Billion revenue; >20,000 employees; active in >120 countries) and lays out the research methodology and potential focus areas for further studies.}, subject = {Lean Management}, language = {en} } @inproceedings{KopperWestner, author = {Kopper, Andreas and Westner, Markus}, title = {Towards a Taxonomy for Shadow IT}, series = {Proceedings of the 22nd Americas Conference on Information Systems (AMCIS 2016), San Diego, August 11-14}, booktitle = {Proceedings of the 22nd Americas Conference on Information Systems (AMCIS 2016), San Diego, August 11-14}, pages = {1 -- 10}, abstract = {In a comprehensive literature review, we identified 21 different terms used for Shadow IT related concepts. This variety makes it difficult to identify related research and build upon it. To address this ambiguity, we reduce the different terms to six distinct concepts by developing a taxonomy and examining their relation¬ships. We do so by using a rigorous iterative methodology to identify common characteristics and to classify terms along them. By clustering the results, we derive and visualize the taxonomy. The identified concepts are Feral Practices, Workarounds, Shadow IT, Shadow Systems, Un-enacted Projects, and Shadow Sourcing. We elaborate on the concepts along their characteristics and clearly define and delimit them. As a result, we create a guide for their usage, increase search- and comparability, and unify existing knowledge.}, subject = {Informationstechnik}, language = {en} } @inproceedings{KopperWestner, author = {Kopper, Andreas and Westner, Markus}, title = {Deriving a Framework for Causes, Consequences, and Governance of Shadow IT from Literature}, series = {Proceedings zur Multikonferenz Wirtschaftsinformatik 2016 (MKWI 2016), Technische Universit{\"a}t Ilmenau, Th{\"u}ringen, 09.-11. M{\"a}rz 2016}, booktitle = {Proceedings zur Multikonferenz Wirtschaftsinformatik 2016 (MKWI 2016), Technische Universit{\"a}t Ilmenau, Th{\"u}ringen, 09.-11. M{\"a}rz 2016}, pages = {1687 -- 1698}, abstract = {Shadow IT is a widespread phenomenon which includes systems, services, and processes that are not part of the "official" corporate IT. The topic is still an emerging research area and slowly gaining traction in recent years but a state of the art analysis is missing to date. We therefore conduct a structured literature review to derive a framework for causes, consequences, and governance of Shadow IT. We identify motivators, enablers, and missing barriers as causes for Shadow IT, both positive and negative consequences on an organizational and a technical level and governance approaches which focus on clearance of existing or prevention of future Shadow IT. Our review reveals that constructivist, qualitative design using a case study approach dominates existing research. There are no dominant theories yet to explain Shadow IT. We also highlight possibilities for future research to focus on the less explored governance aspect.}, subject = {Informationsmanagement}, language = {en} } @inproceedings{SonnleitnerWestner, author = {Sonnleitner, Daniel and Westner, Markus}, title = {Quo vadis IT infrastructure}, series = {Proceedings of the 22nd UKAIS Conference : Ubiquitous Information Systems: Surviving and thriving in a connected society, 2017 Oxford, April 3rd-5th 2017}, booktitle = {Proceedings of the 22nd UKAIS Conference : Ubiquitous Information Systems: Surviving and thriving in a connected society, 2017 Oxford, April 3rd-5th 2017}, pages = {14}, abstract = {Many IT organizations are confronted with the question whether to modernize their IT infrastructure. While most data centers run on a virtualized environment, Cloud Computing technology emerges with new characteristics on fast provision of standardized resources in a scalable IT infrastructure. Public cloud vendors offer IT services on demand, so that IT organizations do not have to operate their own hardware. Moreover, private cloud architectures gain influence, claiming to provide flexible and elastic IT infrastructure. The paper at hand guides the strategic decision for adoption of Cloud Computing on IT infrastructure. Therefore, we first introduce a taxonomy for IT infrastructure encompassing a technological and a sourcing perspective. Second, we evaluate selective areas of the taxonomy adopting the SWOT framework to understand both opportunities and challenges of Cloud Computing for IT infrastructure from a business perspective.}, subject = {Cloud Computing}, language = {en} } @article{StrahringerWestnerBary, author = {Strahringer, Susanne and Westner, Markus and Bary, Benedikt von}, title = {IT-Backsourcing}, series = {Das Wirtschaftsstudium : wisu}, journal = {Das Wirtschaftsstudium : wisu}, number = {6}, publisher = {Lange ; Mohr}, address = {D{\"u}sseldorf ; T{\"u}bingen}, pages = {702 -- 706}, abstract = {The importance of information systems (IS) for companies has grown rapidly over the recent years. For example, companies from various industries are focusing their efforts to digitize business models, to adopt agile forms of collaboration, and to leverage automation of routine tasks. This forces companies to review their IS sourcing strategies and to potentially consider alternatives for current outsourcing contracts. One potential option could be to backsource IS services currently performed by external vendors. Based on empirical observations, previous academics defined it as the repatriation of all assets, activities, and skills needed to perform IS services back in-house, which had been outsourced previously to one or multiple vendors. The distinctive characteristic of backsourcing is the change in ownership back to the mother organization. This distinguishes the term backsourcing from similar terms, e.g., backshoring, reshoring, or relocating, which rather focus on the change in location of the service delivery. At the initial sourcing decision, the strategy to outsource an IS service was considered most promising. However, certain developments both inside the company, but also on a broader industry level may lead to a re-evaluation of the situation and thus to an adjustment of the original sourcing strategy. Over the last years, there has been a strong increase in cloud-based services and a shift towards the deployment of standardized, almost "industrialized" applications as services. Before, large companies leveraged their size in realizing economies of scale within their sourcing volumes. The raise of cloud computing as well as standardization of service delivery decreased those benefits and led towards a decline in large outsourcing contracts across a variety of services and a growth of multi-sourcing of individual IS services from the respective "best-in-breed" vendors for shorter time periods. Besides sourcing the best vendor for each service, companies that implement multi-sourcing strategies additionally aim for cost benefits due to an increased competition between vendors, and an increase in agility and adaptability. At the same time, a move towards multi-sourcing strategies with shorter contract durations leads to an increase in so-called "second generation sourcing decisions", namely whether to continue outsourcing a respective service or to bring the service back in-house. Given the developments within the IS environment, this research projects aims at understanding why IS services are backsourced and which factors influence a company's decision to backsource an IS service.}, subject = {Betriebliches Informationssystem}, language = {de} } @inproceedings{Westner, author = {Westner, Markus}, title = {Video-enhanced lectures in high-teaching-load environments with limited resources}, series = {Proceddings of the 11th International Technology, Education and Development Conference (INTED 2017), Valencia, Spain. 6-8 March}, booktitle = {Proceddings of the 11th International Technology, Education and Development Conference (INTED 2017), Valencia, Spain. 6-8 March}, doi = {10.21125/inted.2017.0168}, pages = {197 -- 207}, abstract = {Massive Open Online Courses (MOOCs) have been gaining a lot of attention in the last years. Those courses and their videos are often professionally produced and incorporate a significant investment of time and financial resources. In many cases such courses are "flagship" productions of the associated school or university and produced with budgets lecturers in other institutions do not have available. This makes the use of videos in a regular teaching environment challenging. In addition, lecturers often act in high-teaching-load environments further tightening their capacity constraints. This raises the question whether and how lecturers can benefit from videos in their lectures for increased teaching effectiveness while not sacrificing teaching efficiency. The paper at hand attempts to address this question by providing a critical perspective on the use of videos in a high-teaching-load environment characterized by little financial and staff resource availability. The paper thereby builds upon the three years' experience of its author in using videos to enhance lectures in German tertiary education institutions in a multi-language, i.e., English and German, teaching environment. The presented findings are both relevant for teaching practice and research: lecturers may benefit from the presented ideas and experiences and may adopt them for their teaching. Researchers may find starting points for new research opportunities on the effectiveness and efficiency of video-enhanced lecturing and learning. The paper is organized as follows. Section 2 describes the context of the study from an institutional and technological perspective. Section 3 outlines the methodology applied and 4 how data was collected. Results from data analysis are presented in section 5. The paper concludes with a reflective summary and outlook in section 6.}, subject = {Hochschulbildung}, language = {en} } @inproceedings{WestnerKennedyFurlong, author = {Westner, Markus and Kennedy, F. and Furlong, A.}, title = {Global student collaboration through international blended learning}, series = {Proceedings of the 10th Annual International Conference of Education, Research and Innovation (ICERI2017), Seville, Spain. 16-18 November}, booktitle = {Proceedings of the 10th Annual International Conference of Education, Research and Innovation (ICERI2017), Seville, Spain. 16-18 November}, doi = {10.21125/iceri.2017.2030}, pages = {7625 -- 7631}, abstract = {In today's business, collaboration in globally distributed teams becomes more and more common. This is particularly the case in professional services and information systems (IS) where the immaterial nature of services makes globally distributed service creation easily possible. Consequently, companies expect that graduates have intercultural skills and that they are able to work in globally distributed teams, especially in professional services like consulting or in IS. However, management or IS curriculums often lack courses that teach those respective skills. The suggested course attempts to fill this gap through an innovative course design and delivery. The course intends to replicate a professional project environment in which the students are supposed to deliver a project as a joint international team. In the beginning of the course, students learn key aspects of project management, intercultural management, distributed collaboration, and the professional services industry in a self-paced manner through video lectures. Then they form teams, plan their project, and subsequently execute their project plan jointly. Instructors from the participating institutions supervise and coach the students. The project execution is supposed to resemble a business project with a meeting schedule, agreed deliverables, regular steering committees in which the instructors play the role of the clients. This paper outlines the concept of this international blended-teaching course. It suggests potential learning objectives, a course description, a teaching syllabus, and an assessment framework.}, subject = {Integriertes Lernen}, language = {en} } @inproceedings{KobusWestner, author = {Kobus, J{\"o}rn and Westner, Markus}, title = {Lean Management of IT Organizations}, series = {Proceedings of the 19th Pacific Asia Conference in Information Systems (PACIS 2015), Singapore, Jul 5-9}, booktitle = {Proceedings of the 19th Pacific Asia Conference in Information Systems (PACIS 2015), Singapore, Jul 5-9}, pages = {16}, abstract = {Lean Management has been successfully applied by companies around the world, mainly in production/manufacturing functions. Recently, the interest to investigate a wider application of Lean Management especially in service functions increased. However, it is not clear how Lean Management can be applied to IT organizations. Therefore, this study aims to provide an overview on common characteristics and future research directions. A literature review on existing scholarly research from January 2004 to June 2014 is conducted. Using a database-driven search approach, a total of 1,206 research contributions are found of which 49 were identified as relevant. Results indicate a low theory grounding of mostly formulative and interpretative research items. This implies that research on Lean Management of IT organizations is still at its nascent state. Content-wise, five research themes emerge. The majority of research investigates IT organizations in a role to support Lean Management in production/manufacturing functions (determining "what to work on"), therefore more research on how Lean Management can be applied to IT organizations themselves (determining "how to work") could be beneficial. Future research could also try to build on Change Management theories, as the implementation of Lean Management is of transformational character.}, subject = {Lean Management}, language = {en} } @inproceedings{KobusWestner, author = {Kobus, J{\"o}rn and Westner, Markus}, title = {Lean Management of IT Organizations}, series = {Proceedings of the 21th Americas Conference on Information Systems (AMCIS 2015), Puerto Rico, August 13-15}, booktitle = {Proceedings of the 21th Americas Conference on Information Systems (AMCIS 2015), Puerto Rico, August 13-15}, pages = {1 -- 17}, abstract = {Lean Management has been successfully applied in production/manufacturing functions since more than four decades. Recently, the interest to investigate Lean Management also in service functions increased. Therefore, this study aims to (1) Consolidate critical success factors (CSFs) for the implementation of Lean Management of IT organizations; and (2) Describe a theoretical foundation for these CSFs. With respect to (1) a database-driven search was conducted. CSFs then were extracted and categorized. In total 13 CSF groups were assigned to three dimensions: Mindset and behavior; Organization and skills; and Process facilitation and performance management. To understand underlying mechanisms better, and with respect to (2) we related existing (IS) theory to identified groups of CSFs. Especially, five theoretical concepts are discussed: Absorptive capacity, Agency theory, Cognitive dissonance, Dynamic capabilities, and System dynamics. Future research needs to validate the results of (1) and (2) empirically in IT functions.}, subject = {Lean Management}, language = {en} } @inproceedings{Westner, author = {Westner, Markus}, title = {Antecedents of success in IS offshoring projects}, series = {Proceedings of the 17th European Conference on Information Systems (ECIS 2009), Verona}, booktitle = {Proceedings of the 17th European Conference on Information Systems (ECIS 2009), Verona}, pages = {3104 -- 3116}, abstract = {The paper presents a research model and a measurement instrument for a research-in-progress study on the antecedents of success in IS offshoring projects. In this empirical-confirmatory study, we intend to analyse the impact of the constructs "offshoring expertise", "trust in offshore service provider", "project suitability", "knowledge transfer", and "liaison quality" on offshore project success. Constructs and indicators are derived from an extensive literature review. We plan to formulate a structural equation model and to test it using partial least squares (PLS) as an analysis technique. Our research model addresses the paucity of research that quantitatively examines offshoring success.}, subject = {Informationstechnik}, language = {en} } @book{Westner, author = {Westner, Markus}, title = {IS offshoring}, publisher = {Gabler}, address = {Wiesbaden}, isbn = {978-3-8349-2046-1}, doi = {10.1007/978-3-8349-8407-4}, abstract = {Information systems (IS) offshoring describes the transfer of IS services to an offshoring service provider in a near or far away country. It has received growing attention in the past and there is a strong momentum in shifting IS services abroad. Markus Westner examines the IS offshoring phenomenon from the perspective of German companies. He first provides an overview of the current literature in the field of IS offshoring. Based on interviews with 47 industry experts, evaluation criteria for selecting projects for offshoring are identified. Finally, the author examines determinants of IS offshore project success in German companies based on a statistical analysis of 304 projects using structural equation modeling (PLS).}, subject = {Informationssystem}, language = {en} } @techreport{Westner, type = {Working Paper}, author = {Westner, Markus}, title = {Information systems offshoring}, address = {Dresden}, subject = {Informationstechnik}, language = {en} } @incollection{Westner, author = {Westner, Markus}, title = {{\"U}bersicht {\"u}ber aktuelle Weblog-Skripte und -Services}, series = {Weblogs professionell : Grundlagen, Konzepte und Praxis im unternehmerischen Umfeld}, booktitle = {Weblogs professionell : Grundlagen, Konzepte und Praxis im unternehmerischen Umfeld}, editor = {Picot, Arnold and Fischer, Tim}, isbn = {978-3898643757}, pages = {175 -- 190}, subject = {Kommunikation}, language = {de} } @article{StrahringerWestnerKobus, author = {Strahringer, Susanne and Westner, Markus and Kobus, J{\"o}rn}, title = {Lean IT}, series = {WISU - Das Wirtschaftsstudium}, journal = {WISU - Das Wirtschaftsstudium}, number = {1}, pages = {87 -- 92}, subject = {Informationstechnik}, language = {de} } @article{WestnerStrasser, author = {Westner, Markus and Strasser, Artur}, title = {IT-Offshoring}, series = {WISU - Das Wirtschaftsstudium}, journal = {WISU - Das Wirtschaftsstudium}, number = {5}, pages = {650 -- 652}, subject = {Informationsmanagement}, language = {de} } @inproceedings{WestnerStrahringer, author = {Westner, Markus and Strahringer, Susanne}, title = {Current state of IS offshoring research}, series = {M{\"a}ki{\"o}, Juho; Betz, Stefanie; Stephan, Rolf (Eds.): Offshoring of software development. Methods and tools for risk management. Karlsruhe: Universit{\"a}tsverlag Karlsruhe}, booktitle = {M{\"a}ki{\"o}, Juho; Betz, Stefanie; Stephan, Rolf (Eds.): Offshoring of software development. Methods and tools for risk management. Karlsruhe: Universit{\"a}tsverlag Karlsruhe}, pages = {7 -- 22}, abstract = {This paper empirically examines the current state of the IS offshoring phenomenon in Germany regarding project characteristics and success patterns. Relying on a sample of 304 projects conducted at various industry sectors and companies, results show that IS offshoring primarily occurs in sectors Telecommunications and IT at large corporations. Cost reduction is the main reason for going offshore and offshore projects are executed as part of a larger program at companies. Noticeably, most projects are delivered from India. Additionally, neither captive offshoring nor offshore outsourcing dominates as a de-livery option. Comparing different project subgroups regarding project success, the results reveal that projects delivered by an internal or partially owned service provider are more successful. Other project characteristics such as a project's embedded-ness in a larger offshoring program, a project's size, or a project's offshoring degree in terms of relatively offshored labor hours show few significant differences. The paper addresses the paucity of empirical research on the current state of the IS offshoring phenomenon in Germany.}, subject = {Informationsmanagement}, language = {en} } @incollection{Weber, author = {Weber, Karsten}, title = {Non-propriet{\"a}re Software und Geschenk{\"o}konomie: L{\"o}sungen f{\"u}r die digitale Spaltung?}, series = {Vernetzt gespalten. Der Digital Divide in ethischer Perspektive}, booktitle = {Vernetzt gespalten. Der Digital Divide in ethischer Perspektive}, editor = {Scheule, Rupert M. and Capurro, Rafael and Hausmanninger, Thomas}, publisher = {Fink}, address = {M{\"u}nchen}, pages = {189 -- 197}, language = {de} } @incollection{GorlatchDuennweber, author = {Gorlatch, Sergei and D{\"u}nnweber, Jan}, title = {From Grid Middleware to Grid Applications}, series = {Future Generation Grids}, booktitle = {Future Generation Grids}, editor = {Getov, Vladimir and Laforenza, Domenico and Reinefeld, Alexander}, publisher = {Springer Verlag}, address = {Berlin}, isbn = {978-0-387-27935-0}, doi = {10.1007/978-0-387-29445-2_13}, pages = {241 -- 261}, abstract = {This paper deals with the problem of application programming for grid systems that combine heterogeneous data and computational resources via the Internet. We argue that grid programming is still too complex because of the big gap between the currently used and anticipated grid middleware, (e.g., Globus or WSRF) and the application level. We suggest that this gap needs to be closed in future-generation grids and propose a novel approach to bridging the gap by using Higher-Order Components (HOCs) — recurring patterns of parallel behaviour that are provided to the user as program building blocks with pre-packaged implementation and middleware setup. The presentation is illustrated with a simple case study of computing fractal images. Our experiments demonstrate that HOCs can simplify grid application programming significantly, without serious performance loss.}, language = {en} } @article{WeberRinkeAlwardt, author = {Weber, Karsten and Rinke, Bernhard and Alwardt, Christian}, title = {Dr. Seltsam, oder wie ich lernte, die Drohne zu lieben}, series = {TATuP - Zeitschrift f{\"u}r Technikfolgenabsch{\"a}tzung in Theorie und Praxis}, volume = {27}, journal = {TATuP - Zeitschrift f{\"u}r Technikfolgenabsch{\"a}tzung in Theorie und Praxis}, number = {3}, publisher = {Institute for Technology Assessment and Systems Analysis / KIT}, doi = {10.14512/tatup.27.3.11}, pages = {11 -- 13}, abstract = {Drohnen werden inzwischen in vielen und sehr unterschiedlichen Kon-texten verwendet. Aus dem Blickwinkel der Technikfolgenabsch{\"a}tzung (TA) scheint es daher sinnvoll, den Umfang der momentanen und zu-k{\"u}nftigen Nutzung von Drohnen und daraus resultierende Implikatio-nen n{\"a}her zu beleuchten und eine Bestandsaufnahme durchzuf{\"u}hren. Dar{\"u}ber hinaus sollen die voraussichtlichen Pfade der weiteren Tech-nikentwicklung, relevante Akteure und deren Interessenslage sowie zu-k{\"u}nftige Anwendungspotenziale und Einsatzfelder analysiert werden}, language = {de} } @article{Weber, author = {Weber, Karsten}, title = {Technik in der Pflege}, series = {Evangelium und Wissenschaft}, volume = {39}, journal = {Evangelium und Wissenschaft}, number = {1}, language = {de} } @incollection{WeberKleine, author = {Weber, Karsten and Kleine, Nadine}, title = {Cybersecurity in Health Care}, series = {The Ethics of Cybersecurity}, volume = {21}, booktitle = {The Ethics of Cybersecurity}, editor = {Christen, Markus and Gordijn, Bert and Loi, Michele}, publisher = {Springer Nature}, address = {Cham, Switzerland}, isbn = {978-3-030-29053-5}, doi = {10.1007/978-3-030-29053-5_7}, pages = {139 -- 156}, abstract = {Ethical questions have always been crucial in health care; the rapid dissemination of ICT makes some of those questions even more pressing and also raises new ones. One of these new questions is cybersecurity in relation to ethics in health care. In order to more closely examine this issue, this chapter introduces Beauchamp and Childress' four principles of biomedical ethics as well as additional ethical values and technical aims of relevance for health care. Based on this, two case studies—implantable medical devices and electronic Health Card—are presented, which illustrate potential conflicts between ethical values and technical aims as well as between ethical values themselves. It becomes apparent that these conflicts cannot be eliminated in general but must be reconsidered on a case-by-case basis. An ethical debate on cybersecurity regarding the design and implementation of new (digital) technologies in health care is essential.}, language = {en} } @inproceedings{WeberDrueeke, author = {Weber, Karsten and Dr{\"u}eke, Ricarda}, title = {Privacy, personal data protection, and the need to differentiate}, series = {Ethics of New Information Technology. Proceedings of the 6th International Conference of Computer Ethics: Philosophical Enquiries (CEPE2005)}, booktitle = {Ethics of New Information Technology. Proceedings of the 6th International Conference of Computer Ethics: Philosophical Enquiries (CEPE2005)}, editor = {Brey, Philip and Grodzinsky, F. and Introna, L.}, pages = {13}, abstract = {The coming years will be characterized by the development of mobile ICT that will enable con - sumers to use information and communication services everywhere and anytime. Technologies like GPRS, WLAN, or UMTS can be used stand-alone or in combination with other technologies like RFID or GPS to provide, for instance, location-aware services. Mobile ICT is to be expected to evolve to that what often is called Ambient Intelligence, Ubiquitous or Pervasive Computing. It is likely that such new technologies will affect personnel privacy because providing mobile ICT services inherits the identification and often the exact localization of users. In the following text we shall analyze possible threats of privacy. We will distinguish different dimensions or aspects of privacy to show how new technologies can affect them. After that, we shall argue that it is necessary to make a distinction of privacy and data protection: privacy primarily is a matter of social norms and data protection the realm of technical measurements. Additionally, we will provide some empirical evidence that users of the Internet make that distinction. Finally, we will claim that the right to privacy and privacy itself only can be protected if there are widely accepted social norms regarding privacy.}, language = {en} } @article{KopperWestnerStrahringer, author = {Kopper, Andreas and Westner, Markus and Strahringer, Susanne}, title = {From Shadow IT to Business-managed IT: A qualitative comparative analysis to determine configurations for successful management of IT by business entities}, series = {Information Systems and e-Business Management}, volume = {18}, journal = {Information Systems and e-Business Management}, number = {2}, doi = {10.1007/s10257-020-00472-6}, pages = {209 -- 257}, abstract = {Shadow IT describes covert/hidden IT systems that are managed by business entities themselves. Additionally, there are also overt forms in practice, so-called Business-managed IT, which share most of the characteristics of Shadow IT. To better understand this phenomenon, we interviewed 29 executive IT managers about positive and negative cases of Shadow IT and Business-managed IT. By applying qualitative comparative analysis (QCA), we derived four conditions that characterize these cases: Aligned, local, simple, and volatile. The results show that there are three sufficient configurations of conditions that lead to a positive outcome; one of them even encompasses Shadow IT. The most important solution indicates that IT systems managed by business entities are viewed as being positive if they are aligned with the IT department and limited to local requirements. This allows to balance local responsiveness to changing requirements and global standardization. In contrast, IT systems that are not aligned and permanent (and either organization-wide or simple) are consistently considered as negative. Our study is the first empirical quantitative-qualitative study to shed light on the success and failure of Shadow IT and Business-managed IT.}, subject = {Informationsmanagement}, language = {en} } @article{LoiChristenKleineetal., author = {Loi, Michele and Christen, Markus and Kleine, Nadine and Weber, Karsten}, title = {Cybersecurity in health}, series = {Journal of Information, Communication \& Ethics in Society}, volume = {17}, journal = {Journal of Information, Communication \& Ethics in Society}, number = {2}, doi = {10.1108/JICES-12-2018-0095}, pages = {229 -- 245}, abstract = {Purpose Cybersecurity in healthcare has become an urgent matter in recent years due to various malicious attacks on hospitals and other parts of the healthcare infrastructure. The purpose of this paper is to provide an outline of how core values of the health systems, such as the principles of biomedical ethics, are in a supportive or conflicting relation to cybersecurity. Design/methodology/approach This paper claims that it is possible to map the desiderata relevant to cybersecurity onto the four principles of medical ethics, i.e. beneficence, non-maleficence, autonomy and justice, and explore value conflicts in that way. Findings With respect to the question of how these principles should be balanced, there are reasons to think that the priority of autonomy relative to beneficence and non-maleficence in contemporary medical ethics could be extended to value conflicts in health-related cybersecurity. Research limitations/implications However, the tension between autonomy and justice, which relates to the desideratum of usability of information and communication technology systems, cannot be ignored even if one assumes that respect for autonomy should take priority over other moral concerns. Originality/value In terms of value conflicts, most discussions in healthcare deal with the conflict of balancing efficiency and privacy given the sensible nature of health information. In this paper, the authors provide a broader and more detailed outline.}, language = {en} } @article{Weber, author = {Weber, Karsten}, title = {Computers as omnipotent instruments of power}, series = {The ORBIT Journal - An Online Journal for Responsible Research and Innovation in ICT}, volume = {2}, journal = {The ORBIT Journal - An Online Journal for Responsible Research and Innovation in ICT}, number = {1}, publisher = {Elsevier}, doi = {10.29297/orbit.v2i1.97}, pages = {1 -- 19}, abstract = {With examples concerning the development and dissemination of computer technology in the Soviet Union, the U.S., and other Western countries it shall be demonstrated that computer development on the one hand and social change as well as changes in policy making and administration on the other hand are mingled with each other without a clear direction of causation being discernible.It also shall be shown that perceived social and political threats imposed by early computer technology sometimes actually helped to stop or at least slow down social change. One conclusion that can be drawn from the case studies described for RRI is that the conscious steering of innovations fails because of diffuse and uncoordinated resistance from very different stakeholders. The case studies also suggest that the effectiveness of RRI might be rather limited.}, language = {en} } @inproceedings{BrosigWestnerStrahringer, author = {Brosig, Christoph and Westner, Markus and Strahringer, Susanne}, title = {Revisiting the Concept of IT Capabilities in the Era of Digitalization}, series = {2020 IEEE 22nd Conference on Business Informatics (CBI 2020): Antwerp, Belgium, 22-24 June 2020, proceedings}, booktitle = {2020 IEEE 22nd Conference on Business Informatics (CBI 2020): Antwerp, Belgium, 22-24 June 2020, proceedings}, publisher = {IEEE}, doi = {10.1109/CBI49978.2020.00017}, pages = {84 -- 93}, abstract = {In the era of digitalization, companies review how to build competitive advantage drawing on their capabilities. In this context, the paper revisits the concept of IT capabilities. We summarize the "canonical" body of literature to characterize how leading scholars conceptualized and differentiated IT capabilities and then we show how new types of IT capabilities (for example, rising from SMACIT technologies) relate to this. We find that the resource-based view is still leading in how to conceptualize IT capabilities. However, an alternative perspective on IT assets is emerging, looking at it from the angle of digital technologies as stacks. Digital technologies form the foundation for a new technology-driven perspective on IT capabilities. This new view complements the established differentiation of IT capabilities considering IT infrastructure flexibility, IT management, and IT personnel capability. Both perspectives describe the explorative and exploitative nature of IT capabilities. This paper helps scholars and practitioners to clearly distinguish different perspectives of IT capabilities on how to build a competitive advantage from IT today.}, subject = {Informationstechnik}, language = {en} } @incollection{WeberDrueekeSchulz, author = {Weber, Karsten and Dr{\"u}eke, Ricarda and Schulz, Axel}, title = {Mobile ICT in public spaces and its impact on privacy}, series = {Societies and Cities in the Age of Instant Access}, volume = {88}, booktitle = {Societies and Cities in the Age of Instant Access}, editor = {Miller, Harvey J.}, publisher = {Springer}, address = {Berlin}, doi = {10.1007/1-4020-5427-0_13}, pages = {197 -- 208}, language = {en} } @article{FrommeldHaugCurrleetal., author = {Frommeld, Debora and Haug, Sonja and Currle, Edda and Weber, Karsten}, title = {Telepr{\"a}senzroboter in der Schlaganfallrehabilitation. Bericht {\"u}ber eine empirische Studie zu Robotern in Pflege und Therapie}, series = {CAREkonkret}, volume = {25}, journal = {CAREkonkret}, number = {19}, publisher = {Vincentz}, address = {Hannover}, pages = {5 -- 5}, abstract = {Die Studie untersucht, wie Telepr{\"a}senzroboter nach einem Schlaganfall die Rehabilitation unterst{\"u}tzen k{\"o}nnen.}, language = {de} } @incollection{Weber, author = {Weber, Karsten}, title = {Technik in der Pflege: Bestandsaufnahme, Entwicklungsm{\"o}glichkeiten und normative Bewertung}, series = {Neue Technologien f{\"u}r die Pflege ; grundlegende Reflexionen und pragmatische Befunde}, booktitle = {Neue Technologien f{\"u}r die Pflege ; grundlegende Reflexionen und pragmatische Befunde}, number = {174}, editor = {H{\"u}lsken-Gießler, M. and Kreutzer, Susanne and D{\"u}tthorn, Nadin}, publisher = {Vandenhoeck \& Ruprecht}, address = {G{\"o}ttingen}, isbn = {978-3-7370-1202-7}, doi = {10.14220/9783737012027.153}, language = {de} } @inproceedings{WeberHaugSchlegletal., author = {Weber, Karsten and Haug, Sonja and Schlegl, Thomas and Pohlt, Clemens and H{\"o}cherl, Johannes}, title = {Kollaborative Robotik als Beispiel der Mensch-Maschine-Interaktion}, series = {Tagung Technikfolgenabsch{\"a}tzung, 19.06.2017, Akademie der Wissenschaften Wien}, booktitle = {Tagung Technikfolgenabsch{\"a}tzung, 19.06.2017, Akademie der Wissenschaften Wien}, language = {de} } @article{SonarWeber, author = {Sonar, Arne and Weber, Karsten}, title = {KI gestern und heute : Einsichten aus der Fr{\"u}hgeschichte der KI f{\"u}r aktuelle ethische {\"U}berlegungen zum Einsatz von KI in der Medizin}, series = {Arbeit}, volume = {29}, journal = {Arbeit}, number = {2}, doi = {10.1515/arbeit-2020-0009}, pages = {105 -- 122}, abstract = {Der Einzug K{\"u}nstlicher Intelligenz (KI) in die Medizin scheint angesichts der Nutzenpotenziale unvermeidlich. Durch den Agentencharakter KI-basierter Systeme ergeben sich teils neuartige normative An- und Herausforderungen. F{\"u}r den hochgradig sensiblen Anwendungsbereich der Medizin erscheint es daher notwendig, den KI-Einsatz mit ethischen Leitlinien einzuhegen. Dies wirft die Frage auf, auf welche Erfahrungsbasis eine ethische Fundierung des Einsatzes KI-basierter Technik gestellt werden k{\"o}nnte. Damit ist kein Schluss vom Sein auf das Sollen gemeint, sondern die Ber{\"u}cksichtigung bereits gef{\"u}hrter normativer Debatten. Eine M{\"o}glichkeit, sich der normativen Landschaft der KI anzun{\"a}hern, liegt in der Auseinandersetzung mit der Entwicklungsgeschichte der KI und den damit verbundenen Debatten um ethische und soziale Aspekte. Mit diesem explorativen Ansatz k{\"o}nnen relevante Problemfelder identifiziert, vorl{\"a}ufige Gestaltungs- und Einsatzempfehlungen f{\"u}r KI-Systeme in der Praxis formuliert und Vorschl{\"a}ge zu deren Einbettung in existierende Organisationsstrukturen generiert werden.}, language = {de} } @inproceedings{StoerlMuellerTekleabetal., author = {St{\"o}rl, Uta and M{\"u}ller, Daniel and Tekleab, Alexander and Tolale, Stephane and Stenzel, Julian and Klettke, Meike and Scherzinger, Stefanie and Storl, Uta and Muller, Daniel}, title = {Curating Variational Data in Application Development}, series = {2018 IEEE 34th International Conference on Data Engineering, 16-19 April 2018, Paris, France}, booktitle = {2018 IEEE 34th International Conference on Data Engineering, 16-19 April 2018, Paris, France}, publisher = {IEEE}, doi = {10.1109/ICDE.2018.00187}, pages = {1605 -- 1608}, abstract = {Building applications for processing data lakes is a software engineering challenge. We present Darwin, a middleware for applications that operate on variational data. This concerns data with heterogeneous structure, usually stored within a schema-flexible NoSQL database. Darwin assists application developers in essential data and schema curation tasks: Upon request, Darwin extracts a schema description, discovers the history of schema versions, and proposes mappings between these versions. Users of Darwin may interactively choose which mappings are most realistic. Darwin is further capable of rewriting queries at runtime, to ensure that queries also comply with legacy data. Alternatively, Darwin can migrate legacy data to reduce the structural heterogeneity. Using Darwin, developers may thus evolve their data in sync with their code. In our hands-on demo, we curate synthetic as well as real-life datasets.}, language = {en} } @inproceedings{MauererScherzinger, author = {Mauerer, Wolfgang and Scherzinger, Stefanie}, title = {Nullius in Verba: Reproducibility for Database Systems Research, Revisited}, series = {2021 IEEE 37th International Conference on Data Engineering (ICDE 2021): 19-22 April 2021, Chania, Greece}, booktitle = {2021 IEEE 37th International Conference on Data Engineering (ICDE 2021): 19-22 April 2021, Chania, Greece}, editor = {Ailamaki, Anastasia}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-7281-9184-3}, doi = {10.1109/ICDE51399.2021.00270}, pages = {2377 -- 2380}, abstract = {Over the last decade, reproducibility of experimental results has been a prime focus in database systems research, and many high-profile conferences award results that can be independently verified. Since database systems research involves complex software stacks that non-trivially interact with hardware, sharing experimental setups is anything but trivial: Building a working reproduction package goes far beyond providing a DOI to some repository hosting data, code, and setup instructions.This tutorial revisits reproducible engineering in the face of state-of-the-art technology, and best practices gained in other computer science research communities. In particular, in the hands-on part, we demonstrate how to package entire system software stacks for dissemination. To ascertain long-term reproducibility over decades (or ideally, forever), we discuss why relying on open source technologies massively employed in industry has essential advantages over approaches crafted specifically for research. Supplementary material shows how version control systems that allow for non-linearly rewriting recorded history can document the structured genesis behind experimental setups in a way that is substantially easier to understand, without involvement of the original authors, compared to detour-ridden, strictly historic evolution.}, language = {en} } @inproceedings{WinterDuennweber, author = {Winter, Christoph and D{\"u}nnweber, Jan}, title = {Model-Driven Development of GPU Applications}, series = {Parallel Computing: On the Road to Exascale}, booktitle = {Parallel Computing: On the Road to Exascale}, publisher = {IOS Press}, address = {Amsterdam, Netherlands}, isbn = {978-1-61499-621-7}, doi = {10.3233/978-1-61499-621-7-227}, pages = {227 -- 236}, abstract = {Programming GPUs with low-level libraries like CUDA and OpenCL is a tedious and error-prone task. Fortunately, algorithmic skeletons can shield developers from the complexity of parallel programming by encapsulating common parallel computing patterns. However, this simplification typically constrains programmers to write their applications using the GPU library employed by the skeleton implementation. In this work, we combine skeletal programming with modeldriven software development (MDSD) to increase the freedom of choice regarding the employed GPU library instead of leaving all technical decisions to the skeleton implementation. We present a code-generator that transforms models comprising skeletons, their input data and input functions to parallel C++ code while taking care of data-offset calculations. The generator has been tested using different GPU and multi-GPU communication libraries such as Thrust and CUDA-MPI. We demonstrate our novel approach to GPU programming with two example applications: affinity propagation and n-body simulation.}, language = {en} } @article{GroegerHautmannLoescheletal., author = {Gr{\"o}ger, Christian and Hautmann, Matthias G. and L{\"o}schel, Rainer and Repp, Natalia and K{\"o}lbl, Oliver and Dobler, Barbara}, title = {Re-irradiation of spinal column metastases by IMRT: Impact of setup errors on the dose distribution}, series = {Radiation Oncology}, volume = {8}, journal = {Radiation Oncology}, number = {269}, publisher = {BMC, Part of Springer Nature}, doi = {10.1186/1748-717X-8-269}, abstract = {Background This study investigates the impact of an automated image guided patient setup correction on the dose distribution for ten patients with in-field IMRT re-irradiation of vertebral metastases. Methods 10 patients with spinal column metastases who had previously been treated with 3D-conformal radiotherapy (3D-CRT) were simulated to have an in-field recurrence. IMRT plans were generated for treatment of the vertebrae sparing the spinal cord. The dose distributions were compared for a patient setup based on skin marks only and a Cone Beam CT (CBCT) based setup with translational and rotational couch corrections using an automatic robotic image guided couch top (Elekta - HexaPOD™ IGuide® - system). The biological equivalent dose (BED) was calculated to evaluate and rank the effects of the automatic setup correction for the dose distribution of CTV and spinal cord. Results The mean absolute value (± standard deviation) over all patients and fractions of the translational error is 6.1 mm (±4 mm) and 2.7° (±1.1 mm) for the rotational error. The dose coverage of the 95\% isodose for the CTV is considerable decreased for the uncorrected table setup. This is associated with an increasing of the spinal cord dose above the tolerance dose. Conclusions An automatic image guided table correction ensures the delivery of accurate dose distribution and reduces the risk of radiation induced myelopathy.}, language = {en} } @inproceedings{SelgradLierDoerntleinetal., author = {Selgrad, Kai and Lier, Alexander and D{\"o}rntlein, Jan and Reiche, Oliver and Stamminger, Marc}, title = {A High-Performance Image Processing DSL for Heterogeneous Architectures}, series = {Proceedings of the 9th European Lisp Symposium (ELS 2016), Krakow, Poland}, booktitle = {Proceedings of the 9th European Lisp Symposium (ELS 2016), Krakow, Poland}, editor = {Durand, Ir{\`e}ne}, publisher = {ACM}, address = {New York, NY, USA}, isbn = {978-2-9557474-0-7}, pages = {39 -- 46}, abstract = {Over the last decade a number of high performance, domain-specific languages (DSLs) have started to grow and help tackle the problem of ever diversifying hard- and software employed in fields such as HPC (high performance computing), medical imaging, computer vision etc. Most of those approaches rely on frameworks such as LLVM for efficient code generation and, to reach a broader audience, take input in C-like form. In this paper we present a DSL for image processing that is on-par with competing methods, yet its design principles are in strong contrast to previous approaches. Our tool chain is much simpler, easing the burden on implementors and maintainers, while our output, C-family code, is both adaptable and shows high performance. We believe that our methodology provides a faster evaluation of language features and abstractions in the domains above.}, language = {en} } @inproceedings{KlettkeAwolinStoerletal., author = {Klettke, Meike and Awolin, Hannes and St{\"o}rl, Uta and M{\"u}ller, Daniel and Scherzinger, Stefanie and Storl, Uta and Muller, Daniel}, title = {Uncovering the evolution history of data lakes}, series = {2017 IEEE International Conference on Big Data (Big Data),,11-14 Dec. 2017, Boston, MA, USA}, booktitle = {2017 IEEE International Conference on Big Data (Big Data),,11-14 Dec. 2017, Boston, MA, USA}, publisher = {IEEE}, doi = {10.1109/BigData.2017.8258204}, pages = {2462 -- 2471}, abstract = {Data accumulating in data lakes can become inaccessible in the long run when its semantics are not available. The heterogeneity of data formats and the sheer volumes of data collections prohibit cleaning and unifying the data manually. Thus, tools for automated data lake analysis are of great interest. In this paper, we target the particular problem of reconstructing the schema evolution history from data lakes. Knowing how the data is structured, and how this structure has evolved over time, enables programmatic access to the lake. By deriving a sequence of schema versions, rather than a single schema, we take into account structural changes over time. Moreover, we address the challenge of detecting inclusion dependencies. This is a prerequisite for mapping between succeeding schema versions, and in particular, detecting nontrivial changes such as a property having been moved or copied. We evaluate our approach for detecting inclusion dependencies using the MovieLens dataset, as well an adaption of a dataset containing botanical descriptions, to cover specific edge cases.}, language = {en} } @inproceedings{MauererRamsauerLucasetal., author = {Mauerer, Wolfgang and Ramsauer, Ralf and Lucas, Edson R. F. and Scherzinger, Stefanie}, title = {Silentium! Run-Analyse-Eradicate the Noise out of the DB/OS Stack}, series = {Datenbanksysteme f{\"u}r Business, Technologie und Web (BTW 2021): 13.-17. September 2021, Dresden, Deutschland}, booktitle = {Datenbanksysteme f{\"u}r Business, Technologie und Web (BTW 2021): 13.-17. September 2021, Dresden, Deutschland}, publisher = {Gesellschaft f{\"u}r Informatik}, doi = {10.18420/btw2021-21}, pages = {397 -- 421}, abstract = {When multiple tenants compete for resources, database performance tends to suffer. Yet there are scenarios where guaranteed sub-millisecond latencies are crucial, such as in real-time data processing, IoT devices, or when operating in safety-critical environments. In this paper, we study how to make query latencies deterministic in the face of noise (whether caused by other tenants or unrelated operating system tasks). We perform controlled experiments with an in-memory database engine in a multi-tenant setting, where we successively eradicate noisy interference from within the system software stack, to the point where the engine runs close to bare-metal on the underlying hardware. We show that we can achieve query latencies comparable to the database engine running as the sole tenant, but without noticeably impacting the workload of competing tenants. We discuss these results in the context of ongoing efforts to build custom operating systems for database workloads, and point out that for certain use cases, the margin for improvement is rather narrow. In fact, for scenarios like ours, existing operating systems might just be good enough, provided that they are expertly configured. We then critically discuss these findings in the light of a broader family of database systems (e.g., including disk-based), and how to extend the approach of this paper accordingly. Low-latency databases; tail latency; real-time databases; bounded-time query processing; DB-OS co-engineering}, language = {de} } @inproceedings{HeinzSchildgen, author = {Heinz, Florian and Schildgen, Johannes}, title = {A Data Model and Operations for Higher-Dimensional Moving Objects in Databases}, series = {EMODE '23: Proceedings of the 1st ACM SIGSPATIAL International Workshop on Methods for Enriched Mobility Data: Emerging issues and Ethical perspectives 2023, Hamburg, 23 November 2023}, booktitle = {EMODE '23: Proceedings of the 1st ACM SIGSPATIAL International Workshop on Methods for Enriched Mobility Data: Emerging issues and Ethical perspectives 2023, Hamburg, 23 November 2023}, publisher = {ACM}, isbn = {979-8-4007-0347-8}, doi = {10.1145/3615885.3628006}, pages = {30 -- 39}, abstract = {Moving Object Databases are designed to store and process database objects with attributes that can change over time. Simple examples are moving points, that change position over time, a bit more complex are moving regions, that can also change shape. The spatial and spatiotemporal object types in current moving objects databases are limited to two dimensions. This work strives to extend the set of spatial moving object types into the third and even higher dimensions while preserving a consistent family of operations for it. A robust algorithm for the interpolation of two regions to a moving region of any dimensionality is developed, as well as the fundamental ideas for several other operations.}, language = {en} } @incollection{FrikelHaltmeier, author = {Frikel, J{\"u}rgen and Haltmeier, Markus}, title = {Sparse Regularization of Inverse Problems by Operator-Adapted Frame Thresholding}, series = {Mathematics of Wave Phenomena}, booktitle = {Mathematics of Wave Phenomena}, editor = {D{\"o}rfler, Willy and Hochbruck, Marlis and Hundertmark, Dirk and Reichel, Wolfgang and Rieder, Andreas}, edition = {1st ed.}, publisher = {Birkh{\"a}user; Springer International Publishing}, address = {Cham}, isbn = {978-3-030-47173-6}, doi = {10.1007/978-3-030-47174-3_10}, pages = {163 -- 178}, abstract = {We analyze sparse frame based regularization of inverse problems by means of a diagonal frame decomposition (DFD) for the forward operator, which generalizes the SVD. The DFD allows to define a non-iterative (direct) operator-adapted frame thresholding approach which we show to provide a convergent regularization method with linear convergence rates. These results will be compared to the well-known analysis and synthesis variants of sparse ℓ1-regularization which are usually implemented thorough iterative schemes. If the frame is a basis (non-redundant case), the three versions of sparse regularization, namely synthesis and analysis variants of ℓ1-regularization as well as the DFD thresholding are equivalent. However, in the redundant case, those three approaches are pairwise different.}, language = {en} } @article{PlonusVoglFloeter, author = {Plonus, Rene-Marcel and Vogl, Stefanie and Floeter, Jens}, title = {Automatic Segregation of Pelagic Habitats}, series = {Frontiers in Marine Science}, journal = {Frontiers in Marine Science}, edition = {8}, publisher = {Frontiers}, doi = {10.3389/fmars.2021.754375}, pages = {11 S.}, abstract = {It remains difficult to segregate pelagic habitats since structuring processes are dynamic on a wide range of scales and clear boundaries in the open ocean are non-existent. However, to improve our knowledge about existing ecological niches and the processes shaping the enormous diversity of marine plankton, we need a better understanding of the driving forces behind plankton patchiness. Here we describe a new machine-learning method to detect and quantify pelagic habitats based on hydrographic measurements. An Autoencoder learns two-dimensional, meaningful representations of higher-dimensional micro-habitats, which are characterized by a variety of biotic and abiotic measurements from a high-speed ROTV. Subsequently, we apply a density-based clustering algorithm to group similar micro-habitats into associated pelagic macro-habitats in the German Bight of the North Sea. Three distinct macro-habitats, a "surface mixed layer," a "bottom layer," and an exceptionally "productive layer" are consistently identified, each with its distinct plankton community. We provide evidence that the model detects relevant features like the doming of the thermocline within an Offshore Wind Farm or the presence of a tidal mixing front.}, language = {en} } @incollection{PereiraPassosLopesetal., author = {Pereira, Clayton R. and Passos, Leandro A. and Lopes, Ricardo R. and Weber, Silke A. T. and Hook, Christian and Papa, Joao Paulo}, title = {Parkinson's Disease Identification Using Restricted Boltzmann Machines}, series = {Computer Analysis of Images and Patterns, 17th International Conference, CAIP 2017, Ystad, Sweden, August 22-24, 2017, Proceedings, Part II}, volume = {10425}, booktitle = {Computer Analysis of Images and Patterns, 17th International Conference, CAIP 2017, Ystad, Sweden, August 22-24, 2017, Proceedings, Part II}, publisher = {Springer}, isbn = {978-3-319-64697-8}, doi = {10.1007/978-3-319-64698-5_7}, pages = {70 -- 80}, abstract = {Currently, Parkinson's Disease (PD) has no cure or accurate diagnosis, reaching approximately 60, 000 new cases yearly and worldwide, being more often in the elderly population. Its main symptoms can not be easily uncorrelated with other illness, being way more difficult to be identified at the early stages. As such, computer-aided tools have been recently used to assist in this task, but the challenge in the automatic identification of Parkinson's Disease still persists. In order to cope with this problem, we propose to employ Restricted Boltzmann Machines (RBMs) to learn features in an unsupervised fashion by analyzing images from handwriting exams, which aim at assessing the writing skills of potential individuals. These are one of the main symptoms of PD-prone people, since such kind of ability ends up being severely affected. We show that RBMs can learn proper features that help supervised classifiers in the task of automatic identification of PD patients, as well as one can obtain a more compact representation of the exam for the sake of storage and computational load purposes.}, language = {en} } @inproceedings{StragapedeVeraRodriguezTolosanaetal., author = {Stragapede, Giuseppe and Vera-Rodriguez, Ruben and Tolosana, Ruben and Morales, Aythami and DeAndres-Tame, Ivan and Damer, Naser and Fierrez, Julian and Garcia, Javier-Ortega and Gonzalez, Nahuel and Shadrikov, Andrei and Gordin, Dmitrii and Schmitt, Leon and Wimmer, Daniel and Großmann, Christoph and Krieger, Joerdis and Heinz, Florian and Krestel, Ron and Mayer, Christoffer and Haberl, Simon and Gschrey, Helena and Yamagishi, Yosuke and Saha, Sanjay and Rasnayaka, Sanka and Wickramanayake, Sandareka and Sim, Terence and Gutfeter, Weronika and Baran, Adam and Krzyszt{\´o}n, Mateusz and Jask{\´o}ła, Przemysław}, title = {IEEE BigData 2023 Keystroke Verification Challenge (KVC)}, series = {2023 IEEE International Conference on Big Data,15-18 December 2023, Sorrento, Italy}, booktitle = {2023 IEEE International Conference on Big Data,15-18 December 2023, Sorrento, Italy}, editor = {He, Jingrui}, publisher = {IEEE}, address = {Piscataway, NJ, USA}, isbn = {979-8-3503-2445-7}, doi = {10.1109/BigData59044.2023.10386557}, pages = {6092 -- 6100}, language = {en} }