TY - GEN A1 - Han van der, Aa A1 - Di Ciccio, Claudio A1 - Leopold, Henrik A1 - Reijers, Hajo A. T1 - Extracting Declarative Process Models from Natural Language T2 - Advanced Information Systems Engineering (CAISE 2019) N2 - Process models are an important means to capture information on organizational operations and often represent the starting point for process analysis and improvement. Since the manual elicitation and creation of process models is a time-intensive endeavor, a variety of techniques have been developed that automatically derive process models from textual process descriptions. However, these techniques, so far, only focus on the extraction of traditional, imperative process models. The extraction of declarative process models, which allow to effectively capture complex process behavior in a compact fashion, has not been addressed. In this paper we close this gap by presenting the first automated approach for the extraction of declarative process models from natural language. To achieve this, we developed tailored Natural Language Processing techniques that identify activities and their inter-relations from textual constraint descriptions. A quantitative evaluation shows that our approach is able to generate constraints that closely resemble those established by humans. Therefore, our approach provides automated support for an otherwise tedious and complex manual endeavor. KW - Declarative modelling KW - Natural language processing KW - Model extraction Y1 - 2019 SN - 978-3-030-21290-2 SN - 978-3-030-21289-6 U6 - https://doi.org/10.1007/978-3-030-21290-2_23 SN - 0302-9743 SN - 1611-3349 VL - 11483 SP - 365 EP - 382 PB - Springer CY - Cham ER - TY - GEN A1 - Halfpap, Stefan A1 - Schlosser, Rainer T1 - Workload-Driven Fragment Allocation for Partially Replicated Databases Using Linear Programming T2 - 2019 IEEE 35th International Conference on Data Engineering (ICDE) N2 - In replication schemes, replica nodes can process read-only queries on snapshots of the master node without violating transactional consistency. By analyzing the workload, we can identify query access patterns and replicate data depending to its access frequency. In this paper, we define a linear programming (LP) model to calculate the set of partial replicas with the lowest overall memory capacity while evenly balancing the query load. Furthermore, we propose a scalable decomposition heuristic to calculate solutions for larger problem sizes. While guaranteeing the same performance as state-of-the-art heuristics, our decomposition approach calculates allocations with up to 23% lower memory footprint for the TPC-H benchmark. KW - database replication KW - allocation problem KW - linear programming Y1 - 2019 SN - 978-1-5386-7474-1 SN - 978-1-5386-7475-8 U6 - https://doi.org/10.1109/ICDE.2019.00188 SN - 1084-4627 SN - 2375-026X SN - 1063-6382 SP - 1746 EP - 1749 PB - IEEE CY - New York ER - TY - GEN A1 - Halfpap, Stefan A1 - Schlosser, Rainer T1 - A Comparison of Allocation Algorithms for Partially Replicated Databases T2 - 2019 IEEE 35th International Conference on Data Engineering (ICDE) N2 - Increasing demand for analytical processing capabilities can be managed by replication approaches. However, to evenly balance the replicas' workload shares while at the same time minimizing the data replication factor is a highly challenging allocation problem. As optimal solutions are only applicable for small problem instances, effective heuristics are indispensable. In this paper, we test and compare state-of-the-art allocation algorithms for partial replication. By visualizing and exploring their (heuristic) solutions for different benchmark workloads, we are able to derive structural insights and to detect an algorithm's strengths as well as its potential for improvement. Further, our application enables end-to-end evaluations of different allocations to verify their theoretical performance. Y1 - 2019 SN - 978-1-5386-7474-1 SN - 978-1-5386-7475-8 U6 - https://doi.org/10.1109/ICDE.2019.00226 SN - 1084-4627 SN - 2375-026X SN - 1063-6382 SP - 2008 EP - 2011 PB - IEEE CY - New York ER - TY - GEN A1 - Haarmann, Stephan A1 - Batoulis, Kimon A1 - Nikaj, Adriatik A1 - Weske, Mathias T1 - DMN Decision Execution on the Ethereum Blockchain T2 - Advanced Information Systems Engineering, CAISE 2018 N2 - Recently blockchain technology has been introduced to execute interacting business processes in a secure and transparent way. While the foundations for process enactment on blockchain have been researched, the execution of decisions on blockchain has not been addressed yet. In this paper we argue that decisions are an essential aspect of interacting business processes, and, therefore, also need to be executed on blockchain. The immutable representation of decision logic can be used by the interacting processes, so that decision taking will be more secure, more transparent, and better auditable. The approach is based on a mapping of the DMN language S-FEEL to Solidity code to be run on the Ethereum blockchain. The work is evaluated by a proof-of-concept prototype and an empirical cost evaluation. KW - Blockchain KW - Interacting processes KW - DMN Y1 - 2018 SN - 978-3-319-91563-0 SN - 978-3-319-91562-3 U6 - https://doi.org/10.1007/978-3-319-91563-0_20 SN - 0302-9743 SN - 1611-3349 VL - 10816 SP - 327 EP - 341 PB - Springer CY - Cham ER - TY - GEN A1 - Gross, Sascha A1 - Tiwari, Abhishek A1 - Hammer, Christian T1 - PlAnalyzer BT - a precise approach for pendingIntent vulnerability analysis T2 - Computer Security(ESORICS 2018), PT II N2 - In this work we propose PIAnalyzer, a novel approach to analyze PendingIntent related vulnerabilities. We empirically evaluate PIAnalyzer on a set of 1000 randomly selected applications from the Google Play Store and find 1358 insecure usages of Pendinglntents, including 70 severe vulnerabilities. We manually inspected ten reported vulnerabilities out of which nine correctly reported vulnerabilities, indicating a high precision. The evaluation shows that PIAnalyzer is efficient with an average execution time of 13 seconds per application. KW - Android KW - Intent analysis KW - Information flow control KW - Static analysis Y1 - 2018 SN - 978-3-319-98989-1 SN - 978-3-319-98988-4 U6 - https://doi.org/10.1007/978-3-319-98989-1_3 SN - 0302-9743 SN - 1611-3349 VL - 11099 SP - 41 EP - 59 PB - Springer CY - Cham ER - TY - GEN A1 - Gonzalez-Lopez, Fernanda A1 - Pufahl, Luise T1 - A Landscape for Case Models T2 - Enterprise, Business-Process and Information Systems Modeling N2 - Case Management is a paradigm to support knowledge-intensive processes. The different approaches developed for modeling these types of processes tend to result in scattered models due to the low abstraction level at which the inherently complex processes are therein represented. Thus, readability and understandability is more challenging than that of traditional process models. By reviewing existing proposals in the field of process overviews and case models, this paper extends a case modeling language - the fragment-based Case Management (fCM) language - with the goal of modeling knowledge-intensive processes from a higher abstraction level - to generate a so-called fCM landscape. This proposal is empirically evaluated via an online experiment. Results indicate that interpreting an fCM landscape might be more effective and efficient than interpreting an informationally equivalent case model. KW - Case Management KW - Process landscape KW - Process map KW - Process architecture KW - Process model Y1 - 2019 SN - 978-3-030-20618-5 SN - 978-3-030-20617-8 U6 - https://doi.org/10.1007/978-3-030-20618-5_6 SN - 1865-1348 VL - 352 SP - 87 EP - 102 PB - Springer CY - Berlin ER - TY - GEN A1 - Gawron, Marian A1 - Cheng, Feng A1 - Meinel, Christoph T1 - Automatic vulnerability classification using machine learning T2 - Risks and Security of Internet and Systems N2 - The classification of vulnerabilities is a fundamental step to derive formal attributes that allow a deeper analysis. Therefore, it is required that this classification has to be performed timely and accurate. Since the current situation demands a manual interaction in the classification process, the timely processing becomes a serious issue. Thus, we propose an automated alternative to the manual classification, because the amount of identified vulnerabilities per day cannot be processed manually anymore. We implemented two different approaches that are able to automatically classify vulnerabilities based on the vulnerability description. We evaluated our approaches, which use Neural Networks and the Naive Bayes methods respectively, on the base of publicly known vulnerabilities. KW - Vulnerability analysis KW - Security analytics KW - Data mining Machine learning KW - Neural Networks Y1 - 2018 SN - 978-3-319-76687-4 SN - 978-3-319-76686-7 U6 - https://doi.org/10.1007/978-3-319-76687-4_1 SN - 0302-9743 SN - 1611-3349 SP - 3 EP - 17 PB - Springer CY - Cham ER - TY - GEN A1 - Galke, Lukas A1 - Gerstenkorn, Gunnar A1 - Scherp, Ansgar T1 - A case atudy of closed-domain response suggestion with limited training data T2 - Database and Expert Systems Applications : DEXA 2018 Iinternational workshops N2 - We analyze the problem of response suggestion in a closed domain along a real-world scenario of a digital library. We present a text-processing pipeline to generate question-answer pairs from chat transcripts. On this limited amount of training data, we compare retrieval-based, conditioned-generation, and dedicated representation learning approaches for response suggestion. Our results show that retrieval-based methods that strive to find similar, known contexts are preferable over parametric approaches from the conditioned-generation family, when the training data is limited. We, however, identify a specific representation learning approach that is competitive to the retrieval-based approaches despite the training data limitation. Y1 - 2018 SN - 978-3-319-99133-7 SN - 978-3-319-99132-0 U6 - https://doi.org/10.1007/978-3-319-99133-7_18 SN - 1865-0929 SN - 1865-0937 VL - 903 SP - 218 EP - 229 PB - Springer CY - Berlin ER - TY - GEN A1 - Friedrich, Tobias T1 - From graph theory to network science BT - the natural emergence of hyperbolicity (Tutorial) T2 - 36th International Symposium on Theoretical Aspects of Computer Science (STACS 2019) N2 - Network science is driven by the question which properties large real-world networks have and how we can exploit them algorithmically. In the past few years, hyperbolic graphs have emerged as a very promising model for scale-free networks. The connection between hyperbolic geometry and complex networks gives insights in both directions: (1) Hyperbolic geometry forms the basis of a natural and explanatory model for real-world networks. Hyperbolic random graphs are obtained by choosing random points in the hyperbolic plane and connecting pairs of points that are geometrically close. The resulting networks share many structural properties for example with online social networks like Facebook or Twitter. They are thus well suited for algorithmic analyses in a more realistic setting. (2) Starting with a real-world network, hyperbolic geometry is well-suited for metric embeddings. The vertices of a network can be mapped to points in this geometry, such that geometric distances are similar to graph distances. Such embeddings have a variety of algorithmic applications ranging from approximations based on efficient geometric algorithms to greedy routing solely using hyperbolic coordinates for navigation decisions. KW - Graph Theory KW - Graph Algorithms KW - Network Science KW - Hyperbolic Geometry Y1 - 2019 SN - 978-3-95977-100-9 U6 - https://doi.org/10.4230/LIPIcs.STACS.2019.5 VL - 126 PB - Schloss Dagstuhl-Leibniz-Zentrum für Informatik CY - Dragstuhl 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 - Elsaid, Mohamed Esam A1 - Shawish, Ahmed A1 - Meinel, Christoph T1 - Enhanced cost analysis of multiple virtual machines live migration in VMware environments T2 - 2018 IEEE 8th International Symposium on Cloud and Service Computing (SC2) N2 - Live migration is an important feature in modern software-defined datacenters and cloud computing environments. Dynamic resource management, load balance, power saving and fault tolerance are all dependent on the live migration feature. Despite the importance of live migration, the cost of live migration cannot be ignored and may result in service availability degradation. Live migration cost includes the migration time, downtime, CPU overhead, network and power consumption. There are many research articles that discuss the problem of live migration cost with different scopes like analyzing the cost and relate it to the parameters that control it, proposing new migration algorithms that minimize the cost and also predicting the migration cost. For the best of our knowledge, most of the papers that discuss the migration cost problem focus on open source hypervisors. For the research articles focus on VMware environments, none of the published articles proposed migration time, network overhead and power consumption modeling for single and multiple VMs live migration. In this paper, we propose empirical models for the live migration time, network overhead and power consumption for single and multiple VMs migration. The proposed models are obtained using a VMware based testbed. Y1 - 2018 SN - 978-1-7281-0236-8 U6 - https://doi.org/10.1109/SC2.2018.00010 SP - 16 EP - 23 PB - IEEE CY - New York ER - TY - GEN A1 - Discher, Sören A1 - Richter, Rico A1 - Döllner, Jürgen Roland Friedrich ED - Spencer, SN T1 - A scalable webGL-based approach for visualizing massive 3D point clouds using semantics-dependent rendering techniques T2 - Web3D 2018: The 23rd International ACM Conference on 3D Web Technology N2 - 3D point cloud technology facilitates the automated and highly detailed digital acquisition of real-world environments such as assets, sites, cities, and countries; the acquired 3D point clouds represent an essential category of geodata used in a variety of geoinformation applications and systems. In this paper, we present a web-based system for the interactive and collaborative exploration and inspection of arbitrary large 3D point clouds. Our approach is based on standard WebGL on the client side and is able to render 3D point clouds with billions of points. It uses spatial data structures and level-of-detail representations to manage the 3D point cloud data and to deploy out-of-core and web-based rendering concepts. By providing functionality for both, thin-client and thick-client applications, the system scales for client devices that are vastly different in computing capabilities. Different 3D point-based rendering techniques and post-processing effects are provided to enable task-specific and data-specific filtering and highlighting, e.g., based on per-point surface categories or temporal information. A set of interaction techniques allows users to collaboratively work with the data, e.g., by measuring distances and areas, by annotating, or by selecting and extracting data subsets. Additional value is provided by the system's ability to display additional, context-providing geodata alongside 3D point clouds and to integrate task-specific processing and analysis operations. We have evaluated the presented techniques and the prototype system with different data sets from aerial, mobile, and terrestrial acquisition campaigns with up to 120 billion points to show their practicality and feasibility. KW - 3D Point Clouds KW - web-based rendering KW - point-based rendering Y1 - 2018 SN - 978-1-4503-5800-2 U6 - https://doi.org/10.1145/3208806.3208816 SP - 1 EP - 9 PB - Association for Computing Machinery CY - New York 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 - Combi, Carlo A1 - Oliboni, Barbara A1 - Weske, Mathias A1 - Zerbato, Francesca ED - Trujillo, JC Davis T1 - Conceptual modeling of processes and data BT - Connecting different perspectives T2 - Conceptual Modeling, ER 2018 N2 - Business processes constantly generate, manipulate, and consume data that are managed by organizational databases. Despite being central to process modeling and execution, the link between processes and data is often handled by developers when the process is implemented, thus leaving the connection unexplored during the conceptual design. In this paper, we introduce, formalize, and evaluate a novel conceptual view that bridges the gap between process and data models, and show some kinds of interesting insights that can be derived from this novel proposal. Y1 - 2018 SN - 978-3-030-00847-5 SN - 978-3-030-00846-8 U6 - https://doi.org/10.1007/978-3-030-00847-5_18 SN - 0302-9743 SN - 1611-3349 VL - 11157 SP - 236 EP - 250 PB - Springer CY - Cham ER - TY - GEN A1 - Chakraborty, Dhiman A1 - Hammer, Christian A1 - Bugiel, Sven T1 - Secure Multi-Execution in Android T2 - Proceedings of the 34th ACM/SIGAPP Symposium on Applied Computing N2 - Mobile operating systems, such as Google's Android, have become a fixed part of our daily lives and are entrusted with a plethora of private information. Congruously, their data protection mechanisms have been improved steadily over the last decade and, in particular, for Android, the research community has explored various enhancements and extensions to the access control model. However, the vast majority of those solutions has been concerned with controlling the access to data, but equally important is the question of how to control the flow of data once released. Ignoring control over the dissemination of data between applications or between components of the same app, opens the door for attacks, such as permission re-delegation or privacy-violating third-party libraries. Controlling information flows is a long-standing problem, and one of the most recent and practical-oriented approaches to information flow control is secure multi-execution. In this paper, we present Ariel, the design and implementation of an IFC architecture for Android based on the secure multi-execution of apps. Ariel demonstrably extends Android's system with support for executing multiple instances of apps, and it is equipped with a policy lattice derived from the protection levels of Android's permissions as well as an I/O scheduler to achieve control over data flows between application instances. We demonstrate how secure multi-execution with Ariel can help to mitigate two prominent attacks on Android, permission re-delegations and malicious advertisement libraries. KW - Android KW - Information flow control KW - secure multi-execution Y1 - 2019 SN - 978-1-4503-5933-7 U6 - https://doi.org/10.1145/3297280.3297469 SP - 1934 EP - 1943 PB - Association for Computing Machinery CY - New York ER - TY - GEN A1 - Bruechner, Dominik A1 - Renz, Jan A1 - Klingbeil, Mandy T1 - Creating a Framework for User-Centered Development and Improvement of Digital Education T2 - Scale N2 - We investigate how the technology acceptance and learning experience of the digital education platform HPI Schul-Cloud (HPI School Cloud) for German secondary school teachers can be improved by proposing a user-centered research and development framework. We highlight the importance of developing digital learning technologies in a user-centered way to take differences in the requirements of educators and students into account. We suggest applying qualitative and quantitative methods to build a solid understanding of a learning platform's users, their needs, requirements, and their context of use. After concept development and idea generation of features and areas of opportunity based on the user research, we emphasize on the application of a multi-attribute utility analysis decision-making framework to prioritize ideas rationally, taking results of user research into account. Afterward, we recommend applying the principle build-learn-iterate to build prototypes in different resolutions while learning from user tests and improving the selected opportunities. Last but not least, we propose an approach for continuous short- and long-term user experience controlling and monitoring, extending existing web- and learning analytics metrics. KW - learning platform KW - user experience KW - evaluation KW - HPI Schul-Cloud KW - user research framework KW - user-centered design Y1 - 2019 SN - 978-1-4503-6804-9 U6 - https://doi.org/10.1145/3330430.3333644 PB - Association for Computing Machinery CY - New York ER - TY - GEN A1 - Brinkmann, Maik A1 - Heine, Moreen T1 - Can Blockchain Leverage for New Public Governance? BT - a Conceptual Analysis on Process Level T2 - Proceedings of the 12th International Conference on Theory and Practice of Electronic Governance N2 - New Public Governance (NPG) as a paradigm for collaborative forms of public service delivery and Blockchain governance are trending topics for researchers and practitioners alike. Thus far, each topic has, on the whole, been discussed separately. This paper presents the preliminary results of ongoing research which aims to shed light on the more concrete benefits of Blockchain for the purpose of NPG. For the first time, a conceptual analysis is conducted on process level to spot benefits and limitations of Blockchain-based governance. Per process element, Blockchain key characteristics are mapped to functional aspects of NPG from a governance perspective. The preliminary results show that Blockchain offers valuable support for governments seeking methods to effectively coordinate co-producing networks. However, the extent of benefits of Blockchain varies across the process elements. It becomes evident that there is a need for off-chain processes. It is, therefore, argued in favour of intensifying research on off-chain governance processes to better understand the implications for and influences on on-chain governance. KW - Blockchain KW - New Public Governance KW - Blockchain Governance KW - Co-production KW - Conceptual Fit KW - Blockchain-enabled Governance Y1 - 2019 SN - 978-1-4503-6644-1 U6 - https://doi.org/10.1145/3326365.3326409 SP - 338 EP - 341 PB - Association for Computing Machinery CY - New York ER - TY - GEN A1 - Brand, Thomas A1 - Giese, Holger Burkhard T1 - Towards Generic Adaptive Monitoring T2 - 2018 IEEE 12th International Conference on Self-Adaptive and Self-Organizing Systems (SASO) N2 - Monitoring is a key prerequisite for self-adaptive software and many other forms of operating software. Monitoring relevant lower level phenomena like the occurrences of exceptions and diagnosis data requires to carefully examine which detailed information is really necessary and feasible to monitor. Adaptive monitoring permits observing a greater variety of details with less overhead, if most of the time the MAPE-K loop can operate using only a small subset of all those details. However, engineering such an adaptive monitoring is a major engineering effort on its own that further complicates the development of self-adaptive software. The proposed approach overcomes the outlined problems by providing generic adaptive monitoring via runtime models. It reduces the effort to introduce and apply adaptive monitoring by avoiding additional development effort for controlling the monitoring adaptation. Although the generic approach is independent from the monitoring purpose, it still allows for substantial savings regarding the monitoring resource consumption as demonstrated by an example. Y1 - 2019 SN - 978-1-5386-5172-8 U6 - https://doi.org/10.1109/SASO.2018.00027 SN - 1949-3673 SP - 156 EP - 161 PB - IEEE CY - New York ER - TY - GEN A1 - Brand, Thomas A1 - Giese, Holger T1 - Generic adaptive monitoring based on executed architecture runtime model queries and events T2 - IEEE Xplore N2 - Monitoring is a key functionality for automated decision making as it is performed by self-adaptive systems, too. Effective monitoring provides the relevant information on time. This can be achieved with exhaustive monitoring causing a high overhead consumption of economical and ecological resources. In contrast, our generic adaptive monitoring approach supports effectiveness with increased efficiency. Also, it adapts to changes regarding the information demand and the monitored system without additional configuration and software implementation effort. The approach observes the executions of runtime model queries and processes change events to determine the currently required monitoring configuration. In this paper we explicate different possibilities to use the approach and evaluate their characteristics regarding the phenomenon detection time and the monitoring effort. Our approach allows balancing between those two characteristics. This makes it an interesting option for the monitoring function of self-adaptive systems because for them usually very short-lived phenomena are not relevant. Y1 - 2019 SN - 978-1-7281-2731-6 U6 - https://doi.org/10.1109/SASO.2019.00012 SN - 1949-3673 SP - 17 EP - 22 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 - Bock, Benedikt A1 - Matysik, Jan-Tobias A1 - Krentz, Konrad-Felix A1 - Meinel, Christoph T1 - Link Layer Key Revocation and Rekeying for the Adaptive Key Establishment Scheme T2 - 2019 IEEE 5TH World Forum on internet of things (WF-IOT) N2 - While the IEEE 802.15.4 radio standard has many features that meet the requirements of Internet of things applications, IEEE 802.15.4 leaves the whole issue of key management unstandardized. To address this gap, Krentz et al. proposed the Adaptive Key Establishment Scheme (AKES), which establishes session keys for use in IEEE 802.15.4 security. Yet, AKES does not cover all aspects of key management. In particular, AKES comprises no means for key revocation and rekeying. Moreover, existing protocols for key revocation and rekeying seem limited in various ways. In this paper, we hence propose a key revocation and rekeying protocol, which is designed to overcome various limitations of current protocols for key revocation and rekeying. For example, our protocol seems unique in that it routes around IEEE 802.15.4 nodes whose keys are being revoked. We successfully implemented and evaluated our protocol using the Contiki-NG operating system and aiocoap. KW - IEEE 802.15.4 KW - key management KW - key establishment KW - key revocation KW - rekeying KW - link layer security KW - MAC security Y1 - 2019 SN - 978-1-5386-4980-0 U6 - https://doi.org/10.1109/WF-IoT.2019.8767211 SP - 374 EP - 379 PB - IEEE CY - New York ER - TY - GEN A1 - Blaesius, Thomas A1 - Eube, Jan A1 - Feldtkeller, Thomas A1 - Friedrich, Tobias A1 - Krejca, Martin Stefan A1 - Lagodzinski, Gregor J. A. A1 - Rothenberger, Ralf A1 - Severin, Julius A1 - Sommer, Fabian A1 - Trautmann, Justin T1 - Memory-restricted Routing With Tiled Map Data T2 - 2018 IEEE International Conference on Systems, Man, and Cybernetics (SMC) N2 - Modern routing algorithms reduce query time by depending heavily on preprocessed data. The recently developed Navigation Data Standard (NDS) enforces a separation between algorithms and map data, rendering preprocessing inapplicable. Furthermore, map data is partitioned into tiles with respect to their geographic coordinates. With the limited memory found in portable devices, the number of tiles loaded becomes the major factor for run time. We study routing under these restrictions and present new algorithms as well as empirical evaluations. Our results show that, on average, the most efficient algorithm presented uses more than 20 times fewer tile loads than a normal A*. Y1 - 2018 SN - 978-1-5386-6650-0 U6 - https://doi.org/10.1109/SMC.2018.00567 SN - 1062-922X SP - 3347 EP - 3354 PB - IEEE 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 - GEN A1 - Bin Tareaf, Raad A1 - Berger, Philipp A1 - Hennig, Patrick A1 - Meinel, Christoph T1 - Personality exploration system for online social networks BT - Facebook brands as a use case T2 - 2018 IEEE/WIC/ACM International Conference on Web Intelligence (WI) N2 - User-generated content on social media platforms is a rich source of latent information about individual variables. Crawling and analyzing this content provides a new approach for enterprises to personalize services and put forward product recommendations. In the past few years, brands made a gradual appearance on social media platforms for advertisement, customers support and public relation purposes and by now it became a necessity throughout all branches. This online identity can be represented as a brand personality that reflects how a brand is perceived by its customers. We exploited recent research in text analysis and personality detection to build an automatic brand personality prediction model on top of the (Five-Factor Model) and (Linguistic Inquiry and Word Count) features extracted from publicly available benchmarks. The proposed model reported significant accuracy in predicting specific personality traits form brands. For evaluating our prediction results on actual brands, we crawled the Facebook API for 100k posts from the most valuable brands' pages in the USA and we visualize exemplars of comparison results and present suggestions for future directions. KW - Big Five Model KW - Brand Personality KW - Personality Prediction KW - Machine Learning KW - Social Media Analysis Y1 - 2019 SN - 978-1-5386-7325-6 U6 - https://doi.org/10.1109/WI.2018.00-76 SP - 301 EP - 309 PB - IEEE CY - New York ER - TY - GEN A1 - Bin Tareaf, Raad A1 - Berger, Philipp A1 - Hennig, Patrick A1 - Meinel, Christoph T1 - ASEDS BT - Towards automatic social emotion detection system using facebook reactions T2 - IEEE 20th International Conference on High Performance Computing and Communications; IEEE 16th International Conference on Smart City; IEEE 4th International Conference on Data Science and Systems (HPCC/SmartCity/DSS)) N2 - The Massive adoption of social media has provided new ways for individuals to express their opinion and emotion online. In 2016, Facebook introduced a new reactions feature that allows users to express their psychological emotions regarding published contents using so-called Facebook reactions. In this paper, a framework for predicting the distribution of Facebook post reactions is presented. For this purpose, we collected an enormous amount of Facebook posts associated with their reactions labels using the proposed scalable Facebook crawler. The training process utilizes 3 million labeled posts for more than 64,000 unique Facebook pages from diverse categories. The evaluation on standard benchmarks using the proposed features shows promising results compared to previous research. The final model is able to predict the reaction distribution on Facebook posts with a recall score of 0.90 for "Joy" emotion. KW - Emotion Mining KW - Psychological Emotions KW - Machine Learning KW - Social Media Analysis KW - Natural Language Processing Y1 - 2018 SN - 978-1-5386-6614-2 U6 - https://doi.org/10.1109/HPCC/SmartCity/DSS.2018.00143 SP - 860 EP - 866 PB - IEEE CY - New York ER - TY - GEN A1 - Bilo, Davide A1 - Friedrich, Tobias A1 - Lenzner, Pascal A1 - Melnichenko, Anna T1 - Geometric Network Creation Games T2 - SPAA '19: The 31st ACM Symposium on Parallelism in Algorithms and Architectures N2 - Network Creation Games are a well-known approach for explaining and analyzing the structure, quality and dynamics of real-world networks like the Internet and other infrastructure networks which evolved via the interaction of selfish agents without a central authority. In these games selfish agents which correspond to nodes in a network strategically buy incident edges to improve their centrality. However, past research on these games has only considered the creation of networks with unit-weight edges. In practice, e.g. when constructing a fiber-optic network, the choice of which nodes to connect and also the induced price for a link crucially depends on the distance between the involved nodes and such settings can be modeled via edge-weighted graphs. We incorporate arbitrary edge weights by generalizing the well-known model by Fabrikant et al. [PODC'03] to edge-weighted host graphs and focus on the geometric setting where the weights are induced by the distances in some metric space. In stark contrast to the state-of-the-art for the unit-weight version, where the Price of Anarchy is conjectured to be constant and where resolving this is a major open problem, we prove a tight non-constant bound on the Price of Anarchy for the metric version and a slightly weaker upper bound for the non-metric case. Moreover, we analyze the existence of equilibria, the computational hardness and the game dynamics for several natural metrics. The model we propose can be seen as the game-theoretic analogue of a variant of the classical Network Design Problem. Thus, low-cost equilibria of our game correspond to decentralized and stable approximations of the optimum network design. KW - Network creation games KW - edge-weighted networks KW - price of anarchy KW - Nash equilibrium KW - game dynamics KW - computational hardness Y1 - 2019 SN - 978-1-4503-6184-2 U6 - https://doi.org/10.1145/3323165.3323199 SP - 323 EP - 332 PB - Association for Computing Machinery CY - New York ER - TY - GEN A1 - Bender, Benedict A1 - Grum, Marcus A1 - Gronau, Norbert A1 - Alfa, Attahiru A1 - Maharaj, B. T. T1 - Design of a worldwide simulation system for distributed cyber-physical production networks T2 - 2019 IEEE International Conference on Engineering, Technology and Innovation (ICE/ITMC) N2 - Modern production infrastructures of globally operating companies usually consist of multiple distributed production sites. While the organization of individual sites consisting of Industry 4.0 components itself is demanding, new questions regarding the organization and allocation of resources emerge considering the total production network. In an attempt to face the challenge of efficient distribution and processing both within and across sites, we aim to provide a hybrid simulation approach as a first step towards optimization. Using hybrid simulation allows us to include real and simulated concepts and thereby benchmark different approaches with reasonable effort. A simulation concept is conceptualized and demonstrated qualitatively using a global multi-site example. KW - production networks KW - geographical distribution KW - task realization strategies KW - Industry 4.0 KW - simulation KW - evaluation Y1 - 2019 SN - 978-1-7281-3401-7 SN - 978-1-7281-3402-4 U6 - https://doi.org/10.1109/ICE.2019.8792609 SN - 2334-315X PB - IEEE CY - New York ER - TY - GEN A1 - Bazhenova, Ekaterina A1 - Zerbato, Francesca A1 - Weske, Mathias T1 - Data-Centric Extraction of DMN Decision Models from BPMN Process Models T2 - Business Process Management Workshops N2 - Operational decisions in business processes can be modeled by using the Decision Model and Notation (DMN). The complementary use of DMN for decision modeling and of the Business Process Model and Notation (BPMN) for process design realizes the separation of concerns principle. For supporting separation of concerns during the design phase, it is crucial to understand which aspects of decision-making enclosed in a process model should be captured by a dedicated decision model. Whereas existing work focuses on the extraction of decision models from process control flow, the connection of process-related data and decision models is still unexplored. In this paper, we investigate how process-related data used for making decisions can be represented in process models and we distinguish a set of BPMN patterns capturing such information. Then, we provide a formal mapping of the identified BPMN patterns to corresponding DMN models and apply our approach to a real-world healthcare process. KW - Business process models KW - Process-related data KW - Decision models Y1 - 2018 SN - 978-3-319-74030-0 SN - 978-3-319-74029-4 U6 - https://doi.org/10.1007/978-3-319-74030-0_43 SN - 1865-1348 VL - 308 SP - 542 EP - 555 PB - Springer CY - Berlin ER - TY - GEN A1 - Bauer, Matthias A1 - Malchow, Martin A1 - Meinel, Christoph T1 - Improving access to online lecture videos T2 - Proceedings of 2018 IEEE Global Engineering Education Conference (EDUCON) N2 - In university teaching today, it is common practice to record regular lectures and special events such as conferences and speeches. With these recordings, a large fundus of video teaching material can be created quickly and easily. Typically, lectures have a length of about one and a half hours and usually take place once or twice a week based on the credit hours. Depending on the number of lectures and other events recorded, the number of recordings available is increasing rapidly, which means that an appropriate form of provisioning is essential for the students. This is usually done in the form of lecture video platforms. In this work, we have investigated how lecture video platforms and the contained knowledge can be improved and accessed more easily by an increasing number of students. We came up with a multistep process we have applied to our own lecture video web portal that can be applied to other solutions as well. KW - E-Learning KW - Lecture Video Archive KW - E-Lecture KW - Lecture Recording KW - HTML5 KW - HLS KW - Flash Y1 - 2018 SN - 978-1-5386-2957-4 U6 - https://doi.org/10.1109/EDUCON.2018.8363361 SN - 2165-9567 SP - 1161 EP - 1168 PB - IEEE CY - New York ER - TY - GEN A1 - Bartz, Christian A1 - Yang, Haojin A1 - Meinel, Christoph T1 - SEE: Towards semi-supervised end-to-end scene text recognition T2 - Proceedings of the Thirty-Second AAAI Conference on Artificial Intelligence, Thirtieth Innovative Applications of Artificial Intelligence Conference, Eight Symposium on Educational Advances in Artificial Intelligence N2 - Detecting and recognizing text in natural scene images is a challenging, yet not completely solved task. In recent years several new systems that try to solve at least one of the two sub-tasks (text detection and text recognition) have been proposed. In this paper we present SEE, a step towards semi-supervised neural networks for scene text detection and recognition, that can be optimized end-to-end. Most existing works consist of multiple deep neural networks and several pre-processing steps. In contrast to this, we propose to use a single deep neural network, that learns to detect and recognize text from natural images, in a semi-supervised way. SEE is a network that integrates and jointly learns a spatial transformer network, which can learn to detect text regions in an image, and a text recognition network that takes the identified text regions and recognizes their textual content. We introduce the idea behind our novel approach and show its feasibility, by performing a range of experiments on standard benchmark datasets, where we achieve competitive results. Y1 - 2018 SN - 978-1-57735-800-8 VL - 10 SP - 6674 EP - 6681 PB - ASSOC Association for the Advancement of Artificial Intelligence CY - Palo Alto ER - TY - GEN A1 - Aranda, Juan A1 - Schölzel, Mario A1 - Mendez, Diego A1 - Carrillo, Henry T1 - An energy consumption model for multiModal wireless sensor networks based on wake-up radio receivers T2 - 2018 IEEE Colombian Conference on Communications and Computing (COLCOM) N2 - Energy consumption is a major concern in Wireless Sensor Networks. A significant waste of energy occurs due to the idle listening and overhearing problems, which are typically avoided by turning off the radio, while no transmission is ongoing. The classical approach for allowing the reception of messages in such situations is to use a low-duty-cycle protocol, and to turn on the radio periodically, which reduces the idle listening problem, but requires timers and usually unnecessary wakeups. A better solution is to turn on the radio only on demand by using a Wake-up Radio Receiver (WuRx). In this paper, an energy model is presented to estimate the energy saving in various multi-hop network topologies under several use cases, when a WuRx is used instead of a classical low-duty-cycling protocol. The presented model also allows for estimating the benefit of various WuRx properties like using addressing or not. KW - Energy efficiency KW - multimodal wireless sensor network KW - low-duty-cycling KW - wake-up radio Y1 - 2018 SN - 978-1-5386-6820-7 U6 - https://doi.org/10.1109/ColComCon.2018.8466728 PB - IEEE CY - New York ER - TY - GEN A1 - Andjelkovic, Marko A1 - Babic, Milan A1 - Li, Yuanqing A1 - Schrape, Oliver A1 - Krstić, Miloš A1 - Kraemer, Rolf T1 - Use of decoupling cells for mitigation of SET effects in CMOS combinational gates T2 - 2018 25th IEEE International Conference on Electronics, Circuits and Systems (ICECS) N2 - This paper investigates the applicability of CMOS decoupling cells for mitigating the Single Event Transient (SET) effects in standard combinational gates. The concept is based on the insertion of two decoupling cells between the gate's output and the power/ground terminals. To verify the proposed hardening approach, extensive SPICE simulations have been performed with standard combinational cells designed in IHP's 130 nm bulk CMOS technology. Obtained simulation results have shown that the insertion of decoupling cells results in the increase of the gate's critical charge, thus reducing the gate's soft error rate (SER). Moreover, the decoupling cells facilitate the suppression of SET pulses propagating through the gate. It has been shown that the decoupling cells may be a competitive alternative to gate upsizing and gate duplication for hardening the gates with lower critical charge and multiple (3 or 4) inputs, as well as for filtering the short SET pulses induced by low-LET particles. KW - decoupling cells KW - radiation hardening KW - SET effects KW - CMOS technology KW - combinational logic Y1 - 2019 SN - 978-1-5386-9562-3 U6 - https://doi.org/10.1109/ICECS.2018.8617996 SP - 361 EP - 364 PB - IEEE 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 -