TY - JOUR A1 - Bleifuss, Tobias A1 - Bornemann, Leon A1 - Johnson, Theodore A1 - Kalashnikov, Dmitri A1 - Naumann, Felix A1 - Srivastava, Divesh T1 - Exploring Change BT - a new dimension of data analytics JF - Proceedings of the VLDB Endowment N2 - Data and metadata in datasets experience many different kinds of change. Values axe inserted, deleted or updated; rows appear and disappear; columns are added or repurposed, etc. In such a dynamic situation, users might have many questions related to changes in the dataset, for instance which parts of the data are trustworthy and which are not? Users will wonder: How many changes have there been in the recent minutes, days or years? What kind of changes were made at which points of time? How dirty is the data? Is data cleansing required? The fact that data changed can hint at different hidden processes or agendas: a frequently crowd-updated city name may be controversial; a person whose name has been recently changed may be the target of vandalism; and so on. We show various use cases that benefit from recognizing and exploring such change. We envision a system and methods to interactively explore such change, addressing the variability dimension of big data challenges. To this end, we propose a model to capture change and the process of exploring dynamic data to identify salient changes. We provide exploration primitives along with motivational examples and measures for the volatility of data. We identify technical challenges that need to be addressed to make our vision a reality, and propose directions of future work for the data management community. Y1 - 2018 U6 - https://doi.org/10.14778/3282495.3282496 SN - 2150-8097 VL - 12 IS - 2 SP - 85 EP - 98 PB - Association for Computing Machinery CY - New York ER - TY - JOUR A1 - Maximova, Maria A1 - Giese, Holger A1 - Krause, Christian T1 - Probabilistic timed graph transformation systems JF - Journal of Logical and Algebraic Methods in Programming N2 - Today, software has become an intrinsic part of complex distributed embedded real-time systems. The next generation of embedded real-time systems will interconnect the today unconnected systems via complex software parts and the service-oriented paradigm. Due to these interconnections, the architecture of systems can be subject to changes at run-time, e.g. when dynamic binding of service end-points is employed or complex collaborations are established dynamically. However, suitable formalisms and techniques that allow for modeling and analysis of timed and probabilistic behavior of such systems as well as of their structure dynamics do not exist so far. To fill the identified gap, we propose Probabilistic Timed Graph Transformation Systems (PTGTSs) as a high-level description language that supports all the necessary aspects of structure dynamics, timed behavior, and probabilistic behavior. We introduce the formal model of PTGTSs in this paper as well as present and formally verify a mapping of models with finite state spaces to probabilistic timed automata (PTA) that allows to use the PRISM model checker to analyze PTGTS models with respect to PTCTL properties. (C) 2018 Elsevier Inc. All rights reserved. KW - Graph transformations KW - Probabilistic timed automata KW - PTCTL KW - PRISM model checker KW - HENSHIN Y1 - 2018 U6 - https://doi.org/10.1016/j.jlamp.2018.09.003 SN - 2352-2208 VL - 101 SP - 110 EP - 131 PB - Elsevier CY - New York ER - TY - GEN A1 - Björk, Jennie A1 - Hölzle, Katharina T1 - Editorial T2 - Creativity and innovation management N2 - "Never doubt that a small group of thoughtful, committed citizens can change the world; indeed, it's the only thing that ever has. - Margaret Mead." With the last issue of this year we want to point out directions towards what will come and what challenges and opportunities lie ahead of us. More needed than ever are joint creative efforts to find ways to collaborate and innovate in order to secure the wellbeing of our earth for the next generation to come. We have found ourselves puzzled that we could assemble a sustainability issue without having a call for papers or a special issue. In fact, many of the submissions we currently receive, deal with sustainable, ecological or novel approaches to management and organizations. As creativity and innovation are undisputable necessary ingredients for reaching the sustainable development goals, empirical proof and research in this area are still in their infancy. While the role of design and design thinking has been highlighted before for solving wicked societal problems, a lot more research is needed which creative and innovative ways organisations and societies can take to find solutions to climate change, poverty, hunger and education. We would therefore like to call to you, our readers and writers to tackle these problems with your research. The first article in this issue addresses one of the above named challenges - the role of innovation for achieving the transition to a low-carbon energy world. In “Innovating for low-carbon energy through hydropower: Enabling a conservation charity's transition to a low-carbon community”, the authors John Gallagher, Paul Coughlan, A. Prysor Williams and Aonghus McNabola look at how an eco-design approach has supported a community transition to low-carbon. They highlight the importance of effective management as well as external collaboration and how the key for success lay in fostering an open environment for creativity and idea sharing. The second article addresses another of the grand challenges, the future of mobility and uses a design-driven approach to develop scenarios for mobility in cities. In “Designing radical innovations of meanings for society: envisioning new scenarios for smart mobility”, the authors Claudio Dell'Era, Naiara Altuna and Roberto Verganti investigate how new meanings can be designed and proposed to society rather than to individuals in the particular context of smart mobility. Through two case studies the authors argue for a multi-level perspective, taking the perspective of the society to solve societal challenges while considering the needs of the individual. The latter is needed because we will not change if our needs are not addressed. Furthermore, the authors find that both, meaning and technology need to be considered to create radical innovation for society. The role of meaning continues in the third article in this issue. The authors Marta Gasparin and William Green show in their article “Reconstructing meaning without redesigning products: The case of the Serie7 chair” how meaning changes over time even though the product remains the same. Through an in-depth retrospective study of the Serie 7 chair the authors investigate the relationship between meaning and the materiality of the object, and show the importance of materiality in constructing product meaning over long periods. Translating this meaning over the course of the innovation process is an important task of management in order to gain buy-in from all involved stakeholders. In the following article “A systematic approach for new technology development by using a biomimicry-based TRIZ contradiction matrix” the authors Byungun Yoon, Chaeguk Lim, Inchae Park and Dooseob Yoon develop a systematic process combining biomimicry and technology-based TRIZ in order to solve technological problems or develop new technologies based on completely new sources or combinations from technology and biology. In the fifth article in this issue “Innovating via Building Absorptive Capacity: Interactive Effects of Top Management Support of Learning, Employee Learning Orientation, and Decentralization Structure” the authors Li-Yun Sun, Chenwei Li and Yuntao Dong examine the effect of learning-related personal and contextual factors on organizational absorptive capability and subsequent innovative performance. The authors find positive effects as well as a moderation influence of decentralized organizational decision-making structures. In the sixth article “Creativity within boundaries: social identity and the development of new ideas in franchise systems” the authors Fanny Simon, Catherine Allix-Desfautaux, Nabil Khelil and Anne-Laure Le Nadant address the paradox of balancing novelty and conformity for creativity in a franchise system. This research is one of the first we know to explicitly address creativity and innovation in such a rigid and pre-determined system. Using a social identity perspective, they can show that social control, which may be exerted by manipulating group identity, is an efficient lever to increase both the creation and the diffusion of the idea. Furthermore, they show that franchisees who do not conform to the norm of the group are stigmatized and must face pressure from the group to adapt their behaviors. This has important implications for future research. In the following article “Exploring employee interactions and quality of contributions in intra-organisational innovation platforms” the authors Dimitra Chasanidou, Njål Sivertstol and Jarle Hildrum examine the user interactions in an intra-organisational innovation platform, and also address the influence of user interactions for idea development. The authors find that employees communicate through the innovation platform with different interaction, contribution and collaboration types and propose three types of contribution qualities—passive, efficient and balanced contribution. In the eighth article “Ready for Take-off”: How Open Innovation influences startup success” Cristina Marullo, Elena Casprini, Alberto di Minin and Andrea Piccaluga seek to predict new venture success based on factors that can be observed in the pre-startup phase. The authors introduce different variables of founding teams and how these relate to startup success. Building on large-scale dataset of submitted business plans at UC Berkeley, they can show that teams with high skills diversity and past joint experience are a lot better able to prevent the risk of business failure at entry and to adapt the internal resources to market conditions. Furthermore, it is crucial for the team to integrate many external knowledge sources into their process (openness) in order to be successful. The crucial role of knowledge and how it is communicated and shared is the focal point of Natalya Sergeeva's and Anna Trifilova's article on “The role of storytelling in the innovation process”. They authors can show how storytelling has an important role to play when it comes to motivating employees to innovate and promoting innovation success stories inside and outside the organization. The deep human desire to hear and experience stories is also addressed in the last article in this issue “Gamification Approaches to the Early Stage of Innovation” by Rui Patricio, Antonio Moreira and Francesco Zurlo. Using gamification approaches at the early stage of innovation promises to create better team coherence, let employees experience fun and engagement, improve communication and foster knowledge exchange. Using an analytical framework, the authors analyze 15 articles that have looked at gamification in the context of innovation management before. They find that gamification indeed supports firms in becoming better at performing complex innovation tasks and managing innovation challenges. Furthermore, gamification in innovation creates a space for inspiration, improves creativity and the generation of high potential ideas. Y1 - 2018 U6 - https://doi.org/10.1111/caim.12298 SN - 0963-1690 SN - 1467-8691 VL - 27 IS - 4 SP - 373 EP - 374 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Orejas, Fernando A1 - Pino, Elvira A1 - Navarro, Marisa A1 - Lambers, Leen T1 - Institutions for navigational logics for graphical structures JF - Theoretical computer science N2 - We show that a Navigational Logic, i.e., a logic to express properties about graphs and about paths in graphs is a semi-exact institution. In this way, we can use a number of operations to structure and modularize our specifications. Moreover, using the properties of our institution, we also show how to structure single formulas, which in our formalism could be quite complex. KW - Institutions KW - Graph logics KW - Navigational logics Y1 - 2018 U6 - https://doi.org/10.1016/j.tcs.2018.02.031 SN - 0304-3975 SN - 1879-2294 VL - 741 SP - 19 EP - 24 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Berti-Equille, Laure A1 - Harmouch, Nazar A1 - Naumann, Felix A1 - Novelli, Noel A1 - Saravanan, Thirumuruganathan T1 - Discovery of genuine functional dependencies from relational data with missing values JF - Proceedings of the VLDB Endowment N2 - Functional dependencies (FDs) play an important role in maintaining data quality. They can be used to enforce data consistency and to guide repairs over a database. In this work, we investigate the problem of missing values and its impact on FD discovery. When using existing FD discovery algorithms, some genuine FDs could not be detected precisely due to missing values or some non-genuine FDs can be discovered even though they are caused by missing values with a certain NULL semantics. We define a notion of genuineness and propose algorithms to compute the genuineness score of a discovered FD. This can be used to identify the genuine FDs among the set of all valid dependencies that hold on the data. We evaluate the quality of our method over various real-world and semi-synthetic datasets with extensive experiments. The results show that our method performs well for relatively large FD sets and is able to accurately capture genuine FDs. Y1 - 2018 U6 - https://doi.org/10.14778/3204028.3204032 SN - 2150-8097 VL - 11 IS - 8 SP - 880 EP - 892 PB - Association for Computing Machinery CY - New York ER - TY - GEN A1 - Alviano, Mario A1 - Romero Davila, Javier A1 - Schaub, Torsten H. T1 - Preference Relations by Approximation T2 - Sixteenth International Conference on Principles of Knowledge Representation and Reasoning N2 - Declarative languages for knowledge representation and reasoning provide constructs to define preference relations over the set of possible interpretations, so that preferred models represent optimal solutions of the encoded problem. We introduce the notion of approximation for replacing preference relations with stronger preference relations, that is, relations comparing more pairs of interpretations. Our aim is to accelerate the computation of a non-empty subset of the optimal solutions by means of highly specialized algorithms. We implement our approach in Answer Set Programming (ASP), where problems involving quantitative and qualitative preference relations can be addressed by ASPRIN, implementing a generic optimization algorithm. Unlike this, chains of approximations allow us to reduce several preference relations to the preference relations associated with ASP’s native weak constraints and heuristic directives. In this way, ASPRIN can now take advantage of several highly optimized algorithms implemented by ASP solvers for computing optimal solutions Y1 - 2018 SP - 2 EP - 11 PB - AAAI Conference on Artificial Intelligence CY - Palo Alto ER - TY - GEN A1 - Risch, Julian A1 - Krestel, Ralf T1 - My Approach = Your Apparatus? BT - Entropy-Based Topic Modeling on Multiple Domain-Specific Text Collections T2 - Libraries N2 - Comparative text mining extends from genre analysis and political bias detection to the revelation of cultural and geographic differences, through to the search for prior art across patents and scientific papers. These applications use cross-collection topic modeling for the exploration, clustering, and comparison of large sets of documents, such as digital libraries. However, topic modeling on documents from different collections is challenging because of domain-specific vocabulary. We present a cross-collection topic model combined with automatic domain term extraction and phrase segmentation. This model distinguishes collection-specific and collection-independent words based on information entropy and reveals commonalities and differences of multiple text collections. We evaluate our model on patents, scientific papers, newspaper articles, forum posts, and Wikipedia articles. In comparison to state-of-the-art cross-collection topic modeling, our model achieves up to 13% higher topic coherence, up to 4% lower perplexity, and up to 31% higher document classification accuracy. More importantly, our approach is the first topic model that ensures disjunct general and specific word distributions, resulting in clear-cut topic representations. KW - Topic modeling KW - Automatic domain term extraction KW - Entropy Y1 - 2018 SN - 978-1-4503-5178-2 U6 - https://doi.org/10.1145/3197026.3197038 SN - 2575-7865 SN - 2575-8152 SP - 283 EP - 292 PB - Association for Computing Machinery CY - New York ER - TY - GEN A1 - Fricke, Andreas A1 - Döllner, Jürgen Roland Friedrich A1 - Asche, Hartmut T1 - Servicification - Trend or Paradigm Shift in Geospatial Data Processing? T2 - Computational Science and Its Applications – ICCSA 2018, PT III N2 - Currently we are witnessing profound changes in the geospatial domain. Driven by recent ICT developments, such as web services, serviceoriented computing or open-source software, an explosion of geodata and geospatial applications or rapidly growing communities of non-specialist users, the crucial issue is the provision and integration of geospatial intelligence in these rapidly changing, heterogeneous developments. This paper introduces the concept of Servicification into geospatial data processing. Its core idea is the provision of expertise through a flexible number of web-based software service modules. Selection and linkage of these services to user profiles, application tasks, data resources, or additional software allow for the compilation of flexible, time-sensitive geospatial data handling processes. Encapsulated in a string of discrete services, the approach presented here aims to provide non-specialist users with geospatial expertise required for the effective, professional solution of a defined application problem. Providing users with geospatial intelligence in the form of web-based, modular services, is a completely different approach to geospatial data processing. This novel concept puts geospatial intelligence, made available through services encapsulating rule bases and algorithms, in the centre and at the disposal of the users, regardless of their expertise. KW - Servicification KW - Geospatial intelligence KW - Spatial data handling systems Y1 - 2018 SN - 978-3-319-95168-3 SN - 978-3-319-95167-6 U6 - https://doi.org/10.1007/978-3-319-95168-3_23 SN - 0302-9743 SN - 1611-3349 VL - 10962 SP - 339 EP - 350 PB - Springer CY - Cham ER - TY - GEN A1 - Reimann, Max A1 - Klingbeil, Mandy A1 - Pasewaldt, Sebastian A1 - Semmo, Amir A1 - Trapp, Matthias A1 - Döllner, Jürgen Roland Friedrich ED - Sourin, A Sourina T1 - MaeSTrO: A Mobile App for Style Transfer Orchestration using Neural Networks T2 - International Conference on Cyberworlds (CW) N2 - Mobile expressive rendering gained increasing popularity among users seeking casual creativity by image stylization and supports the development of mobile artists as a new user group. In particular, neural style transfer has advanced as a core technology to emulate characteristics of manifold artistic styles. However, when it comes to creative expression, the technology still faces inherent limitations in providing low-level controls for localized image stylization. This work enhances state-of-the-art neural style transfer techniques by a generalized user interface with interactive tools to facilitate a creative and localized editing process. Thereby, we first propose a problem characterization representing trade-offs between visual quality, run-time performance, and user control. We then present MaeSTrO, a mobile app for orchestration of neural style transfer techniques using iterative, multi-style generative and adaptive neural networks that can be locally controlled by on-screen painting metaphors. At this, first user tests indicate different levels of satisfaction for the implemented techniques and interaction design. KW - non-photorealistic rendering KW - style transfer Y1 - 2018 SN - 978-1-5386-7315-7 U6 - https://doi.org/10.1109/CW.2018.00016 SP - 9 EP - 16 PB - IEEE CY - New York ER - TY - GEN A1 - Limberger, Daniel A1 - Gropler, Anne A1 - Buschmann, Stefan A1 - Döllner, Jürgen Roland Friedrich A1 - Wasty, Benjamin T1 - OpenLL BT - an API for Dynamic 2D and 3D Labeling T2 - 22nd International Conference Information Visualisation (IV) N2 - Today's rendering APIs lack robust functionality and capabilities for dynamic, real-time text rendering and labeling, which represent key requirements for 3D application design in many fields. As a consequence, most rendering systems are barely or not at all equipped with respective capabilities. This paper drafts the unified text rendering and labeling API OpenLL intended to complement common rendering APIs, frameworks, and transmission formats. For it, various uses of static and dynamic placement of labels are showcased and a text interaction technique is presented. Furthermore, API design constraints with respect to state-of-the-art text rendering techniques are discussed. This contribution is intended to initiate a community-driven specification of a free and open label library. KW - visualization KW - labeling KW - real-time rendering Y1 - 2018 SN - 978-1-5386-7202-0 U6 - https://doi.org/10.1109/iV.2018.00039 SP - 175 EP - 181 PB - IEEE CY - New York ER - TY - JOUR A1 - Vollmer, Jan Ole A1 - Trapp, Matthias A1 - Schumann, Heidrun A1 - Döllner, Jürgen Roland Friedrich T1 - Hierarchical spatial aggregation for level-of-detail visualization of 3D thematic data JF - ACM transactions on spatial algorithms and systems N2 - Thematic maps are a common tool to visualize semantic data with a spatial reference. Combining thematic data with a geometric representation of their natural reference frame aids the viewer’s ability in gaining an overview, as well as perceiving patterns with respect to location; however, as the amount of data for visualization continues to increase, problems such as information overload and visual clutter impede perception, requiring data aggregation and level-of-detail visualization techniques. While existing aggregation techniques for thematic data operate in a 2D reference frame (i.e., map), we present two aggregation techniques for 3D spatial and spatiotemporal data mapped onto virtual city models that hierarchically aggregate thematic data in real time during rendering to support on-the-fly and on-demand level-of-detail generation. An object-based technique performs aggregation based on scene-specific objects and their hierarchy to facilitate per-object analysis, while the scene-based technique aggregates data solely based on spatial locations, thus supporting visual analysis of data with arbitrary reference geometry. Both techniques can apply different aggregation functions (mean, minimum, and maximum) for ordinal, interval, and ratio-scaled data and can be easily extended with additional functions. Our implementation utilizes the programmable graphics pipeline and requires suitably encoded data, i.e., textures or vertex attributes. We demonstrate the application of both techniques using real-world datasets, including solar potential analyses and the propagation of pressure waves in a virtual city model. KW - Level-of-detail visualization KW - spatial aggregation KW - real-time rendering Y1 - 2018 U6 - https://doi.org/10.1145/3234506 SN - 2374-0353 SN - 2374-0361 VL - 4 IS - 3 PB - Association for Computing Machinery CY - New York ER - TY - GEN A1 - Kötzing, Timo A1 - Krejca, Martin Stefan T1 - First-Hitting times under additive drift T2 - Parallel Problem Solving from Nature – PPSN XV, PT II N2 - For the last ten years, almost every theoretical result concerning the expected run time of a randomized search heuristic used drift theory, making it the arguably most important tool in this domain. Its success is due to its ease of use and its powerful result: drift theory allows the user to derive bounds on the expected first-hitting time of a random process by bounding expected local changes of the process - the drift. This is usually far easier than bounding the expected first-hitting time directly. Due to the widespread use of drift theory, it is of utmost importance to have the best drift theorems possible. We improve the fundamental additive, multiplicative, and variable drift theorems by stating them in a form as general as possible and providing examples of why the restrictions we keep are still necessary. Our additive drift theorem for upper bounds only requires the process to be nonnegative, that is, we remove unnecessary restrictions like a finite, discrete, or bounded search space. As corollaries, the same is true for our upper bounds in the case of variable and multiplicative drift. Y1 - 2018 SN - 978-3-319-99259-4 SN - 978-3-319-99258-7 U6 - https://doi.org/10.1007/978-3-319-99259-4_8 SN - 0302-9743 SN - 1611-3349 VL - 11102 SP - 92 EP - 104 PB - Springer CY - Cham ER - TY - GEN A1 - Kötzing, Timo A1 - Krejca, Martin Stefan T1 - First-Hitting times for finite state spaces T2 - Parallel Problem Solving from Nature – PPSN XV, PT II N2 - One of the most important aspects of a randomized algorithm is bounding its expected run time on various problems. Formally speaking, this means bounding the expected first-hitting time of a random process. The two arguably most popular tools to do so are the fitness level method and drift theory. The fitness level method considers arbitrary transition probabilities but only allows the process to move toward the goal. On the other hand, drift theory allows the process to move into any direction as long as it move closer to the goal in expectation; however, this tendency has to be monotone and, thus, the transition probabilities cannot be arbitrary. We provide a result that combines the benefit of these two approaches: our result gives a lower and an upper bound for the expected first-hitting time of a random process over {0,..., n} that is allowed to move forward and backward by 1 and can use arbitrary transition probabilities. In case that the transition probabilities are known, our bounds coincide and yield the exact value of the expected first-hitting time. Further, we also state the stationary distribution as well as the mixing time of a special case of our scenario. Y1 - 2018 SN - 978-3-319-99259-4 SN - 978-3-319-99258-7 U6 - https://doi.org/10.1007/978-3-319-99259-4_7 SN - 0302-9743 SN - 1611-3349 VL - 11102 SP - 79 EP - 91 PB - Springer CY - Cham ER - TY - GEN A1 - Kötzing, Timo A1 - Lagodzinski, Gregor J. A. A1 - Lengler, Johannes A1 - Melnichenko, Anna T1 - Destructiveness of Lexicographic Parsimony Pressure and Alleviation by a Concatenation Crossover in Genetic Programming T2 - Parallel Problem Solving from Nature – PPSN XV N2 - For theoretical analyses there are two specifics distinguishing GP from many other areas of evolutionary computation. First, the variable size representations, in particular yielding a possible bloat (i.e. the growth of individuals with redundant parts). Second, the role and realization of crossover, which is particularly central in GP due to the tree-based representation. Whereas some theoretical work on GP has studied the effects of bloat, crossover had a surprisingly little share in this work. We analyze a simple crossover operator in combination with local search, where a preference for small solutions minimizes bloat (lexicographic parsimony pressure); the resulting algorithm is denoted Concatenation Crossover GP. For this purpose three variants of the wellstudied Majority test function with large plateaus are considered. We show that the Concatenation Crossover GP can efficiently optimize these test functions, while local search cannot be efficient for all three variants independent of employing bloat control. Y1 - 2018 SN - 978-3-319-99259-4 SN - 978-3-319-99258-7 U6 - https://doi.org/10.1007/978-3-319-99259-4_4 SN - 0302-9743 SN - 1611-3349 VL - 11102 SP - 42 EP - 54 PB - Springer CY - Cham ER - TY - JOUR A1 - Bobda, Christophe A1 - Yonga, Franck A1 - Gebser, Martin A1 - Ishebabi, Harold A1 - Schaub, Torsten H. T1 - High-level synthesis of on-chip multiprocessor architectures based on answer set programming JF - Journal of Parallel and Distributed Computing N2 - We present a system-level synthesis approach for heterogeneous multi-processor on chip, based on Answer Set Programming(ASP). Starting with a high-level description of an application, its timing constraints and the physical constraints of the target device, our goal is to produce the optimal computing infrastructure made of heterogeneous processors, peripherals, memories and communication components. Optimization aims at maximizing speed, while minimizing chip area. Also, a scheduler must be produced that fulfills the real-time requirements of the application. Even though our approach will work for application specific integrated circuits, we have chosen FPGA as target device in this work because of their reconfiguration capabilities which makes it possible to explore several design alternatives. This paper addresses the bottleneck of problem representation size by providing a direct and compact ASP encoding for automatic synthesis that is semantically equivalent to previously established ILP and ASP models. We describe a use-case in which designers specify their applications in C/C++ from which optimum systems can be derived. We demonstrate the superiority of our approach toward existing heuristics and exact methods with synthesis results on a set of realistic case studies. (C) 2018 Elsevier Inc. All rights reserved. KW - System design KW - Architecture synthesis KW - Answer set programming KW - Multi-objective optimization KW - Technology mapping KW - Reconfigurable architecture Y1 - 2018 U6 - https://doi.org/10.1016/j.jpdc.2018.02.010 SN - 0743-7315 SN - 1096-0848 VL - 117 SP - 161 EP - 179 PB - Elsevier CY - San Diego ER - TY - JOUR A1 - Menning, Axel A1 - Grasnick, Bastien M. A1 - Ewald, Benedikt A1 - Dobrigkeit, Franziska A1 - Nicolai, Claudia T1 - Verbal focus shifts BT - forms of low coherent statements in design conversations JF - Design Studies N2 - Previous studies on design behaviour indicate that focus shifts positively influence ideational productivity. In this study we want to take a closer look at how these focus shifts look on the verbal level. We describe a mutually influencing relationship between mental focus shifts and verbal low coherent statements. In a case study based on the DTRS11 dataset we identify 297 low coherent statements via a combined topic modelling and manual approach. We introduce a categorization of the different instances of low coherent statements. The results indicate that designers tend to shift topics within an existing design issue instead of completely disrupting it. (C) 2018 Elsevier Ltd. All rights reserved. KW - creativity KW - communication KW - computational models KW - design cognition KW - design behaviour Y1 - 2018 U6 - https://doi.org/10.1016/j.destud.2018.03.003 SN - 0142-694X SN - 1872-6909 VL - 57 SP - 135 EP - 155 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Yousfi, Alaaeddine A1 - Hewelt, Marcin A1 - Bauer, Christine A1 - Weske, Mathias T1 - Toward uBPMN-Based patterns for modeling ubiquitous business processes JF - IEEE Transactions on Industrial Informatics N2 - Ubiquitous business processes are the new generation of processes that pervade the physical space and interact with their environments using a minimum of human involvement. Although they are now widely deployed in the industry, their deployment is still ad hoc . They are implemented after an arbitrary modeling phase or no modeling phase at all. The absence of a solid modeling phase backing up the implementation generates many loopholes that are stressed in the literature. Here, we tackle the issue of modeling ubiquitous business processes. We propose patterns to represent the recent ubiquitous computing features. These patterns are the outcome of an analysis we conducted in the field of human-computer interaction to examine how the features are actually deployed. The patterns' understandability, ease-of-use, usefulness, and completeness are examined via a user experiment. The results indicate that these four indexes are on the positive track. Hence, the patterns may be the backbone of ubiquitous business process modeling in industrial applications. KW - Ubiquitous business process KW - ubiquitous business process model and notation (uBPMN) KW - ubiquitous business process modeling KW - ubiquitous computing (ubicomp) Y1 - 2017 U6 - https://doi.org/10.1109/TII.2017.2777847 SN - 1551-3203 SN - 1941-0050 VL - 14 IS - 8 SP - 3358 EP - 3367 PB - Inst. of Electr. and Electronics Engineers CY - Piscataway ER - TY - GEN A1 - Diaz, Sergio A1 - Mendez, Diego A1 - Schölzel, Mario T1 - Dynamic Gallager-Humblet-Spira Algorithm for Wireless Sensor Networks T2 - 2018 IEEE Colombian Conference on Communications and Computing (COLCOM) N2 - The problem of constructing and maintaining a tree topology in a distributed manner is a challenging task in WSNs. This is because the nodes have limited computational and memory resources and the network changes over time. We propose the Dynamic Gallager-Humblet-Spira (D-GHS) algorithm that builds and maintains a minimum spanning tree. To do so, we divide D-GHS into four phases, namely neighbor discovery, tree construction, data collection, and tree maintenance. In the neighbor discovery phase, the nodes collect information about their neighbors and the link quality. In the tree construction, D-GHS finds the minimum spanning tree by executing the Gallager-Humblet-Spira algorithm. In the data collection phase, the sink roots the minimum spanning tree at itself, and each node sends data packets. In the tree maintenance phase, the nodes repair the tree when communication failures occur. The emulation results show that D-GHS reduces the number of control messages and the energy consumption, at the cost of a slight increase in memory size and convergence time. KW - Minimum spanning tree KW - Tree maintenance Y1 - 2018 SN - 978-1-5386-6820-7 PB - IEEE CY - New York ER - TY - GEN A1 - Boissier, Martin A1 - Kurzynski, Daniel T1 - Workload-Driven Horizontal Partitioning and Pruning for Large HTAP Systems T2 - 2018 IEEE 34th International Conference on Data Engineering Workshops (ICDEW) N2 - Modern server systems with large NUMA architectures necessitate (i) data being distributed over the available computing nodes and (ii) NUMA-aware query processing to enable effective parallel processing in database systems. As these architectures incur significant latency and throughout penalties for accessing non-local data, queries should be executed as close as possible to the data. To further increase both performance and efficiency, data that is not relevant for the query result should be skipped as early as possible. One way to achieve this goal is horizontal partitioning to improve static partition pruning. As part of our ongoing work on workload-driven partitioning, we have implemented a recent approach called aggressive data skipping and extended it to handle both analytical as well as transactional access patterns. In this paper, we evaluate this approach with the workload and data of a production enterprise system of a Global 2000 company. The results show that over 80% of all tuples can be skipped in average while the resulting partitioning schemata are surprisingly stable over time. Y1 - 2018 SN - 978-1-5386-6306-6 U6 - https://doi.org/10.1109/ICDEW.2018.00026 SP - 116 EP - 121 PB - IEEE CY - New York ER - TY - GEN A1 - Patalas-Maliszewska, Justyna A1 - Krebs, Irene T1 - An Information System Supporting the Eliciting of Expert Knowledge for Successful IT Projects T2 - Information and Software Technologies, ICIST 2018 N2 - In order to guarantee the success of an IT project, it is necessary for a company to possess expert knowledge. The difficulty arises when experts no longer work for the company and it then becomes necessary to use their knowledge, in order to realise an IT project. In this paper, the ExKnowIT information system which supports the eliciting of expert knowledge for successful IT projects, is presented and consists of the following modules: (1) the identification of experts for successful IT projects, (2) the eliciting of expert knowledge on completed IT projects, (3) the expert knowledge base on completed IT projects, (4) the Group Method for Data Handling (GMDH) algorithm, (5) new knowledge in support of decisions regarding the selection of a manager for a new IT project. The added value of our system is that these three approaches, namely, the elicitation of expert knowledge, the success of an IT project and the discovery of new knowledge, gleaned from the expert knowledge base, otherwise known as the decision model, complement each other. KW - Expert knowledge KW - IT project KW - Information system KW - GMDH Y1 - 2018 SN - 978-3-319-99972-2 SN - 978-3-319-99971-5 U6 - https://doi.org/10.1007/978-3-319-99972-2_1 SN - 1865-0929 SN - 1865-0937 VL - 920 SP - 3 EP - 13 PB - Springer CY - Berlin ER -