TY - JOUR A1 - Peng, Junjie A1 - Liu, Danxu A1 - Wang, Yingtao A1 - Zeng, Ying A1 - Cheng, Feng A1 - Zhang, Wenqiang T1 - Weight-based strategy for an I/O-intensive application at a cloud data center JF - Concurrency and computation : practice & experience N2 - Applications with different characteristics in the cloud may have different resources preferences. However, traditional resource allocation and scheduling strategies rarely take into account the characteristics of applications. Considering that an I/O-intensive application is a typical type of application and that frequent I/O accesses, especially small files randomly accessing the disk, may lead to an inefficient use of resources and reduce the quality of service (QoS) of applications, a weight allocation strategy is proposed based on the available resources that a physical server can provide as well as the characteristics of the applications. Using the weight obtained, a resource allocation and scheduling strategy is presented based on the specific application characteristics in the data center. Extensive experiments show that the strategy is correct and can guarantee a high concurrency of I/O per second (IOPS) in a cloud data center with high QoS. Additionally, the strategy can efficiently improve the utilization of the disk and resources of the data center without affecting the service quality of applications. KW - IOPS KW - process scheduling KW - random I KW - O KW - small files KW - weight Y1 - 2018 U6 - https://doi.org/10.1002/cpe.4648 SN - 1532-0626 SN - 1532-0634 VL - 30 IS - 19 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Koehler, Friedrich A1 - Koehler, Kerstin A1 - Deckwart, Oliver A1 - Prescher, Sandra A1 - Wegscheider, Karl A1 - Winkler, Sebastian A1 - Vettorazzi, Eik A1 - Polze, Andreas A1 - Stangl, Karl A1 - Hartmann, Oliver A1 - Marx, Almuth A1 - Neuhaus, Petra A1 - Scherf, Michael A1 - Kirwan, Bridget-Anne A1 - Anker, Stefan D. T1 - Telemedical Interventional Management in Heart Failure II (TIM-HF2), a randomised, controlled trial investigating the impact of telemedicine on unplanned cardiovascular hospitalisations and mortality in heart failure patients BT - study design and description of the intervention JF - European Journal of Heart Failure N2 - Background Heart failure (HF) is a complex, chronic condition that is associated with debilitating symptoms, all of which necessitate close follow-up by health care providers. Lack of disease monitoring may result in increased mortality and more frequent hospital readmissions for decompensated HF. Remote patient management (RPM) in this patient population may help to detect early signs and symptoms of cardiac decompensation, thus enabling a prompt initiation of the appropriate treatment and care before a manifestation of HF decompensation. Objective The objective of the present article is to describe the design of a new trial investigating the impact of RPM on unplanned cardiovascular hospitalisations and mortality in HF patients. Methods The TIM-HF2 trial is designed as a prospective, randomised, controlled, parallel group, open (with randomisation concealment), multicentre trial with pragmatic elements introduced for data collection. Eligible patients with HF are randomised (1:1) to either RPM + usual care or to usual care only and are followed for 12 months. The primary outcome is the percentage of days lost due to unplanned cardiovascular hospitalisations or all-cause death. The main secondary outcomes are all-cause and cardiovascular mortality. Conclusion The TIM-HF2 trial will provide important prospective data on the potential beneficial effect of telemedical monitoring and RPM on unplanned cardiovascular hospitalisations and mortality in HF patients. KW - Chronic heart failure KW - Telemonitoring KW - Remote patient management KW - Hospitalisation Y1 - 2018 U6 - https://doi.org/10.1002/ejhf.1300 SN - 1388-9842 SN - 1879-0844 VL - 20 IS - 10 SP - 1485 EP - 1493 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - von Schorlemer, Stephan A1 - Weiß, Christian-Cornelius T1 - data4life - Eine nutzerkontrollierte Gesundheitsdaten-Infrastruktu Y1 - 2019 SN - 978-3-95466-448-1 SN - 978-3-95466-398-9 SP - 249 EP - 258 PB - Medizinisch Wissenschaftliche Verlagsgesellschaft CY - Berlin ER - TY - GEN A1 - Herzog, Benedict A1 - Hönig, Timo A1 - Schröder-Preikschat, Wolfgang A1 - Plauth, Max A1 - Köhler, Sven A1 - Polze, Andreas T1 - Bridging the Gap BT - Energy-efficient Execution of Software Workloads on Heterogeneous Hardware Components T2 - e-Energy '19: Proceedings of the Tenth ACM International Conference on Future Energy Systems N2 - The recent restructuring of the electricity grid (i.e., smart grid) introduces a number of challenges for today's large-scale computing systems. To operate reliable and efficient, computing systems must adhere not only to technical limits (i.e., thermal constraints) but they must also reduce operating costs, for example, by increasing their energy efficiency. Efforts to improve the energy efficiency, however, are often hampered by inflexible software components that hardly adapt to underlying hardware characteristics. In this paper, we propose an approach to bridge the gap between inflexible software and heterogeneous hardware architectures. Our proposal introduces adaptive software components that dynamically adapt to heterogeneous processing units (i.e., accelerators) during runtime to improve the energy efficiency of computing systems. Y1 - 2019 SN - 978-1-4503-6671-7 U6 - https://doi.org/10.1145/3307772.3330176 SP - 428 EP - 430 PB - Association for Computing Machinery CY - New York ER - TY - GEN A1 - Marwecki, Sebastian A1 - Wilson, Andrew D. A1 - Ofek, Eyal A1 - Franco, Mar Gonzalez A1 - Holz, Christian T1 - Mise-Unseen BT - Using Eye-Tracking to Hide Virtual Reality Scene Changes in Plain Sight T2 - UIST '19: Proceedings of the 32nd Annual ACM Symposium on User Interface Software and Technology N2 - Creating or arranging objects at runtime is needed in many virtual reality applications, but such changes are noticed when they occur inside the user's field of view. We present Mise-Unseen, a software system that applies such scene changes covertly inside the user's field of view. Mise-Unseen leverages gaze tracking to create models of user attention, intention, and spatial memory to determine if and when to inject a change. We present seven applications of Mise-Unseen to unnoticeably modify the scene within view (i) to hide that task difficulty is adapted to the user, (ii) to adapt the experience to the user's preferences, (iii) to time the use of low fidelity effects, (iv) to detect user choice for passive haptics even when lacking physical props, (v) to sustain physical locomotion despite a lack of physical space, (vi) to reduce motion sickness during virtual locomotion, and (vii) to verify user understanding during story progression. We evaluated Mise-Unseen and our applications in a user study with 15 participants and find that while gaze data indeed supports obfuscating changes inside the field of view, a change is rendered unnoticeably by using gaze in combination with common masking techniques. KW - Eye-tracking KW - virtual reality KW - change blindness KW - inattentional blindness KW - staging Y1 - 2019 SN - 978-1-4503-6816-2 U6 - https://doi.org/10.1145/3332165.3347919 SP - 777 EP - 789 PB - Association for Computing Machinery CY - New York ER - TY - GEN A1 - Björk, Jennie A1 - Hölze, Katharina T1 - Editorial T2 - Creativity and innovation management Y1 - 2019 U6 - https://doi.org/10.1111/caim.12336 SN - 0963-1690 SN - 1467-8691 VL - 28 IS - 3 SP - 289 EP - 290 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Yousfi, Alaaeddine A1 - Weske, Mathias T1 - Discovering commute patterns via process mining JF - Knowledge and Information Systems N2 - Ubiquitous computing has proven its relevance and efficiency in improving the user experience across a myriad of situations. It is now the ineluctable solution to keep pace with the ever-changing environments in which current systems operate. Despite the achievements of ubiquitous computing, this discipline is still overlooked in business process management. This is surprising, since many of today’s challenges, in this domain, can be addressed by methods and techniques from ubiquitous computing, for instance user context and dynamic aspects of resource locations. This paper takes a first step to integrate methods and techniques from ubiquitous computing in business process management. To do so, we propose discovering commute patterns via process mining. Through our proposition, we can deduce the users’ significant locations, routes, travel times and travel modes. This information can be a stepping-stone toward helping the business process management community embrace the latest achievements in ubiquitous computing, mainly in location-based service. To corroborate our claims, a user study was conducted. The significant places, routes, travel modes and commuting times of our test subjects were inferred with high accuracies. All in all, ubiquitous computing can enrich the processes with new capabilities that go beyond what has been established in business process management so far. KW - Commute pattern KW - Commute process KW - Process mining KW - Ubiquitous computing KW - Location-based services Y1 - 2019 U6 - https://doi.org/10.1007/s10115-018-1255-1 SN - 0219-1377 SN - 0219-3116 VL - 60 IS - 2 SP - 691 EP - 713 PB - Springer CY - London ER - TY - JOUR A1 - Kastius, Alexander A1 - Schlosser, Rainer T1 - Dynamic pricing under competition using reinforcement learning JF - Journal of revenue and pricing management N2 - Dynamic pricing is considered a possibility to gain an advantage over competitors in modern online markets. The past advancements in Reinforcement Learning (RL) provided more capable algorithms that can be used to solve pricing problems. In this paper, we study the performance of Deep Q-Networks (DQN) and Soft Actor Critic (SAC) in different market models. We consider tractable duopoly settings, where optimal solutions derived by dynamic programming techniques can be used for verification, as well as oligopoly settings, which are usually intractable due to the curse of dimensionality. We find that both algorithms provide reasonable results, while SAC performs better than DQN. Moreover, we show that under certain conditions, RL algorithms can be forced into collusion by their competitors without direct communication. KW - Dynamic pricing KW - Competition KW - Reinforcement learning KW - E-commerce KW - Price collusion Y1 - 2021 U6 - https://doi.org/10.1057/s41272-021-00285-3 SN - 1476-6930 SN - 1477-657X VL - 21 IS - 1 SP - 50 EP - 63 PB - Springer Nature Switzerland AG CY - Cham ER - TY - JOUR A1 - Mendling, Jan A1 - Weber, Ingo A1 - van der Aalst, Wil A1 - Brocke, Jan Vom A1 - Cabanillas, Cristina A1 - Daniel, Florian A1 - Debois, Soren A1 - Di Ciccio, Claudio A1 - Dumas, Marlon A1 - Dustdar, Schahram A1 - Gal, Avigdor A1 - Garcia-Banuelos, Luciano A1 - Governatori, Guido A1 - Hull, Richard A1 - La Rosa, Marcello A1 - Leopold, Henrik A1 - Leymann, Frank A1 - Recker, Jan A1 - Reichert, Manfred A1 - Reijers, Hajo A. A1 - Rinderle-Ma, Stefanie A1 - Solti, Andreas A1 - Rosemann, Michael A1 - Schulte, Stefan A1 - Singh, Munindar P. A1 - Slaats, Tijs A1 - Staples, Mark A1 - Weber, Barbara A1 - Weidlich, Matthias A1 - Weske, Mathias A1 - Xu, Xiwei A1 - Zhu, Liming T1 - Blockchains for Business Process Management BT - Challenges and Opportunities JF - ACM Transactions on Management Information Systems N2 - Blockchain technology offers a sizable promise to rethink the way interorganizational business processes are managed because of its potential to realize execution without a central party serving as a single point of trust (and failure). To stimulate research on this promise and the limits thereof, in this article, we outline the challenges and opportunities of blockchain for business process management (BPM). We first reflect how blockchains could be used in the context of the established BPM lifecycle and second how they might become relevant beyond. We conclude our discourse with a summary of seven research directions for investigating the application of blockchain technology in the context of BPM. KW - Blockchain KW - business process management KW - research challenges Y1 - 2018 U6 - https://doi.org/10.1145/3183367 SN - 2158-656X SN - 2158-6578 VL - 9 IS - 1 SP - 1 EP - 16 PB - Association for Computing Machinery CY - New York ER - TY - JOUR A1 - Kossmann, Jan A1 - Halfpap, Stefan A1 - Jankrift, Marcel A1 - Schlosser, Rainer T1 - Magic mirror in my hand, which is the best in the land? BT - an experimental evaluation of index selection algorithms JF - Proceedings of the VLDB Endowment N2 - Indexes are essential for the efficient processing of database workloads. Proposed solutions for the relevant and challenging index selection problem range from metadata-based simple heuristics, over sophisticated multi-step algorithms, to approaches that yield optimal results. The main challenges are (i) to accurately determine the effect of an index on the workload cost while considering the interaction of indexes and (ii) a large number of possible combinations resulting from workloads containing many queries and massive schemata with possibly thousands of attributes.
In this work, we describe and analyze eight index selection algorithms that are based on different concepts and compare them along different dimensions, such as solution quality, runtime, multi-column support, solution granularity, and complexity. In particular, we analyze the solutions of the algorithms for the challenging analytical Join Order, TPC-H, and TPC-DS benchmarks. Afterward, we assess strengths and weaknesses, infer insights for index selection in general and each approach individually, before we give recommendations on when to use which approach. Y1 - 2020 U6 - https://doi.org/10.14778/3407790.3407832 SN - 2150-8097 VL - 13 IS - 11 SP - 2382 EP - 2395 PB - Association for Computing Machinery CY - New York ER -