Thomas Peter Plagemann

• Volnes, Espen; Plagemann, Thomas Peter & Goebel, Vera Hermine (2023). To Migrate or Not to Migrate: An Analysis of Operator Migration in Distributed Stream Processing. IEEE Communications Surveys and Tutorials. ISSN 1553-877X. 26(1), s. 670–705. doi: 10.1109/COMST.2023.3330953. Fulltekst i vitenarkiv Vis sammendrag

  One of the most important issues in distributed data stream processing systems is using operator migration to handle highly variable workloads cost-efficiently and adapt to the needs at any given time on demand. Operator migration is a complex process involving changes in the state and stream management of a running query, typically without any data loss, and with as little disruption to the execution as possible. This tutorial aims to introduce operator migration, explain the core elements of operator migration, and provide the reader with a good understanding of the design alternatives used in existing solutions. We developed a conceptual model to explain the fundamentals of operator migration and introduce a unified terminology, leading to a taxonomy of existing solutions. The conceptual model separates mechanisms, i.e., how to migrate, and policy, i.e., when to migrate. This separation is further applied to structure the description of existing solutions, offering the reader an algorithmic perspective on various design alternatives. To enhance our understanding of the impact of various design alternatives on migration mechanisms, we also conducted an empirical study that provides quantitative insights. The operator downtime for the naïve migration approach is almost 20 times longer than when applying an incremental checkpoint-based approach.

• Gu, He; Plagemann, Thomas Peter; Goebel, Vera Hermine; Benndorf, Maik & Koldehofe, Boris (2023). Differential Privacy for Protecting Private Patterns in Data Streams. I O´Connor, Lisa (Red.), 2023 IEEE 39th International Conference on Data Engineering Workshops (ICDEW). IEEE (Institute of Electrical and Electronics Engineers). ISSN 979-8-3503-2244-6. s. 118–124. doi: 10.1109/ICDEW58674.2023.00025. Fulltekst i vitenarkiv Vis sammendrag

  Complex event processing (CEP) is a powerful and increasingly more important tool to analyse data streams for Internet of Things (IoT) applications. These data streams often contain private information that requires proper protection. However, privacy protection in CEP systems is still in its infancy, and most existing privacy-preserving mechanisms (PPMs) are adopted from those designed for data streams. Such approaches undermine the quality of the entire data stream and limit the performance of IoT applications. In this paper, we attempt to break the limitation and establish a new foundation for PPMs of CEP by proposing a novel pattern-level differential privacy (DP) guarantee. We introduce two PPMs that guarantee pattern-level DP. They operate only on data that correlate with private patterns rather than on the entire data stream, leading to higher data quality. One of the PPMs provides adaptive privacy protection and brings more granularity and generalization. We evaluate the performance of the proposed PPMs with two experiments on a real-world dataset and on a synthetic dataset. The results of the experiments indicate that our proposed privacy guarantee and its PPMs can deliver better data quality under equally strong privacy guarantees, compared to multiple well-known PPMs designed for data streams.

• Kristiansen, Stein; Nikolaidis, Konstantinos; Plagemann, Thomas Peter; Goebel, Vera Hermine; Traaen, Gunn Marit & Øverland, Britt [Vis alle 13 forfattere av denne artikkelen] (2023). A clinical evaluation of a low-cost strain gauge respiration belt and machine learning to detect sleep apnea. Smart Health. ISSN 2352-6483. 27. doi: 10.1016/j.smhl.2023.100373. Fulltekst i vitenarkiv
• Nikolaidis, Konstantinos; Kristiansen, Stein; Plagemann, Thomas Peter; Goebel, Vera Hermine; Liestøl, Knut & Kankanhalli, Mohan [Vis alle 10 forfattere av denne artikkelen] (2022). My Health Sensor, My Classifier - Adapting a Trained Classifier to Unlabeled End-User Data. ACM Transactions on Computing for Healthcare (HEALTH). ISSN 2691-1957. 3(4), s. 1–24. doi: 10.1145/3559767. Fulltekst i vitenarkiv Vis sammendrag

  Sleep apnea is a common yet severely under-diagnosed sleep related disorder. Unattended sleep monitoring at home with low-cost sensors can be leveraged for condition detection, and Machine Learning offers a generalized solution for this task. However, patient characteristics, lack of sufficient training data, and other factors can imply a domain shift between training and end-user data; and reduced task performance. In this work, we address this issue with the aim to achieve personalization based on the patient’s needs. We present an unsupervised domain adaptation (UDA) solution with the constraint that labeled source data are not directly available. Instead, a classifier trained on the source data is provided. Our solution iteratively labels target data sub-regions based on classifier beliefs, and trains new classifiers from the expanding dataset. Experiments with sleep monitoring datasets and various sensors show that our solution outperforms the classifier trained on the source domain, with a kappa coefficient improvement from 0.012 to 0.242. Additionally, we apply our solution to digit classification DA between three well-established datasets, to investigate its generalizability, and allow for related work comparisons. Even without direct access to the source data, it outperforms several well-established UDA methods in these datasets.

• Nikolaidis, Konstantinos; Kristiansen, Stein; Plagemann, Thomas Peter; Goebel, Vera Hermine; Liestøl, Knut & Kankanhalli, Mohan [Vis alle 10 forfattere av denne artikkelen] (2022). Learning Realistic Patterns from Visually Unrealistic Stimuli: Generalization and Data Anonymization (Extended Abstract). I de Raed, Luc (Red.), Proceedings of the Thirty-First International Joint Conference on Artificial Intelligence. AAAI Press. ISSN 978-1-956792-00-3. s. 5762–5766. doi: 10.24963/ijcai.2022/806. Vis sammendrag

  Good training data is a prerequisite to develop useful Machine Learning applications. However, in many domains existing data sets cannot be shared due to privacy regulations (e.g., from medical studies). This work investigates a simple yet unconventional approach for anonymized data synthesis to enable third parties to benefit from such anonymized data. We explore the feasibility of learning implicitly from visually unrealistic, task-relevant stimuli, which are synthesized by exciting the neurons of a trained deep neural network. As such, neuronal excitation can be used to generate synthetic stimuli. The stimuli data is used to train new classification models. Furthermore, we extend this framework to inhibit representations that are associated with specific individuals. Extensive comparative empirical investigation shows that different algorithms trained on the stimuli are able to generalize successfully on the same task as the original model.

• Volnes, Espen; Plagemann, Thomas Peter; Boris, Koldehofe & Goebel, Vera Hermine (2022). Travel light: state shedding for efficient operator migration. I Yonghuan, Zhou (Red.), DEBS '22: Proceedings of the 16th ACM International Conference on Distributed and Event-Based Systems. Association for Computing Machinery (ACM). ISSN 978-1-4503-9308-9. s. 79–84. doi: https:/doi.org/10.1145/3524860.3539638. Vis sammendrag

  Operator migration is a crucial concept to adapt event pro- cessing systems to dynamic changes. When the placement of a stateful operator changes, the operator state must be migrated to the new host. However, operator state size and time constraints can make it impossible to migrate the op- erator without severe Quality of Service (QoS) degradation. As a relief, we propose to perform state shedding in such a situation. The core idea of state shedding is to partition the operator state, assign a utility to each partial state, and use the utility and size of each partial state to identify the most useful partial states that can be migrated in a given time frame. Thus, state shedding can maintain a substantially higher QoS with a lower impact on query results than state- of-the-art solutions targeting consistent state at the old and new host. In this paper, we define this novel approach and in a simulation environment evaluate state shedding in migration scenarios with pattern-matching queries.

• Lindeberg, Morten Gunnar Bjørner & Plagemann, Thomas Peter (2022). A Study on Migration Scheduling in Distributed Stream Processing Engines, ICDCN '22: Proceedings of the 23rd International Conference on Distributed Computing and Networking. Association for Computing Machinery (ACM). ISSN 978-1-4503-9560-1. s. 50–61. doi: 10.1145/3491003.3491008.
• Nikolaidis, Konstantinos; Kristiansen, Stein; Plagemann, Thomas Peter; Goebel, Vera Hermine; Liestøl, Knut & Kankanhalli, Mohan [Vis alle 10 forfattere av denne artikkelen] (2021). Learning realistic patterns from visually unrealistic stimuli: Generalization and data anonymization. The journal of artificial intelligence research. ISSN 1076-9757. 72, s. 1163–1214. doi: 10.1613/JAIR.1.13252. Fulltekst i vitenarkiv Vis sammendrag

  Good training data is a prerequisite to develop useful Machine Learning applications. However, in many domains existing data sets cannot be shared due to privacy regulations (e.g., from medical studies). This work investigates a simple yet unconventional approach for anonymized data synthesis to enable third parties to benefit from such anonymized data. We explore the feasibility of learning implicitly from visually unrealistic, task-relevant stimuli, which are synthesized by exciting the neurons of a trained deep neural network. As such, neuronal excitation can be used to generate synthetic stimuli. The stimuli data is used to train new classification models. Furthermore, we extend this framework to inhibit representations that are associated with specific individuals. We use sleep monitoring data from both an open and a large closed clinical study, and Electroencephalogram sleep stage classification data, to evaluate whether (1) end-users can create and successfully use customized classification models, and (2) the identity of participants in the study is protected. Extensive comparative empirical investigation shows that different algorithms trained on the stimuli are able to generalize successfully on the same task as the original model. Architectural and algorithmic similarity between new and original models play an important role in performance. For similar architectures, the performance is close to that of using the original data (e.g., Accuracy difference of 0.56%-3.82%, Kappa coefficient difference of 0.02-0.08). Further experiments show that the stimuli can provide state-ofthe-art resilience against adversarial association and membership inference attacks.

• Volnes, Espen; Plagemann, Thomas Peter; Goebel, Vera Hermine & Kristiansen, Stein (2021). EXPOSE: Experimental Performance Evaluation of Stream Processing Engines Made Easy. I Nambiar, Raghunath (Red.), Performance Evaluation and Benchmarking 12th TPC Technology Conference. Springer. ISSN 978-3-030-84924-5. s. 18–34. doi: https:/doi.org/10.1007/978-3-030-84924-5_2. Vis sammendrag

  Experimental performance evaluation of stream processing engines (SPE) can be a great challenge. Aiming to make fair comparisons of different SPEs raises this bar even higher. One important reason for this challenge is the fact that these systems often use concepts that require expert knowledge for each SPE. To address this issue, we present Expose, a distributed performance evaluation framework for SPEs that enables a user through a declarative approach to specify experiments and conduct them on multiple SPEs in a fair way and with low effort. Experimenters with few technical skills can define and execute distributed experiments that can easily be replicated. We demonstrate Expose by defining a set of experiments based on the existing NEXMark benchmark and conduct a performance evaluation of Flink, Beam with the Flink runner, Siddhi, T-Rex, and Esper, on powerful and resource-constrained hardware.

• Kristiansen, Stein; Nikolaidis, Konstantinos; Plagemann, Thomas Peter; Goebel, Vera Hermine; Traaen, Gunn Marit & Øverland, Britt [Vis alle 13 forfattere av denne artikkelen] (2021). Machine learning for sleep apnea detection with unattended sleep monitoring at home. ACM Transactions on Computing for Healthcare (HEALTH). ISSN 2691-1957. 2(2). doi: 10.1145/3433987. Vis sammendrag

  Sleep apnea is a common and strongly under-diagnosed severe sleep-related respiratory disorder with periods of disrupted or reduced breathing during sleep. To diagnose sleep apnea, sleep data are collected with either polysomnography or polygraphy and scored by a sleep expert. We investigate in this work the use of supervised machine learning to automate the analysis of polygraphy data from the A3 study containing more than 7,400 hours of sleep monitoring data from 579 patients. We conduct a systematic comparative study of classification performance and resource use with different combinations of 27 classifiers and four sleep signals. The classifiers achieve up to 0.8941 accuracy (kappa: 0.7877) when using all four signal types simultaneously and up to 0.8543 accuracy (kappa: 0.7080) with only one signal, i.e., oxygen saturation. Methods based on deep learning outperform other methods by a large margin. All deep learning methods achieve nearly the same maximum classification performance even when they have very different architectures and sizes. When jointly accounting for classification performance, resource consumption and the ability to achieve with less training data high classification performance, we find that convolutional neural networks substantially outperform the other classifiers.

• Nikolaidis, Konstantinos; Plagemann, Thomas Peter; Kristiansen, Stein; Goebel, Vera Hermine & Kankanhalli, Mohan (2021). Using Under-Trained Deep Ensembles to Learn Under Extreme Label Noise: A Case Study for Sleep Apnea Detection. IEEE Access. ISSN 2169-3536. 9, s. 45919–45934. doi: 10.1109/ACCESS.2021.3067455. Vis sammendrag

  Improper or erroneous labelling can pose a hindrance to reliable generalization for supervised learning. This can have negative consequences, especially for critical fields such as healthcare. We propose an effective new approach for learning under extreme label noise for medical applications like sleep apnea, that is based on under-trained deep ensembles. Each ensemble member is trained with a subset of the training data, to acquire a general overview of the decision boundary separation, without focusing on potentially erroneous details. The accumulated knowledge of the ensemble is combined to form new labels, that determine a better class separation than the original labels. A new model is trained with these labels to generalize reliably despite the label noise. We evaluate our approach on the tasks of sleep apnea detection and sleep apnea severity classification, and observe performance improvement in kappa from 0.02 up-to 0.55.

• Kristiansen, Stein; Goebel, Vera Hermine; Hamborg Andersen, Morten; Plagemann, Thomas Peter; Traaen, Gunn Marit & Øverland, Britt [Vis alle 8 forfattere av denne artikkelen] (2021). Evaluating a Low-Cost Strain Gauge Breathing Sensor for Sleep Apnea Detection at Home. I Gedeon, Ibrahim (Red.), 2021 IEEE International Conference on Communications Workshops (ICC Workshops). IEEE (Institute of Electrical and Electronics Engineers). ISSN 978-1-7281-9441-7. doi: 10.1109/ICCWorkshops50388.2021.9473597. Vis sammendrag

  We report results and experience from a clinical evaluation of a low-cost strain gauge breathing sensor for sleep apnea detection. We collected from 34 individuals 57 nights of unattended sleep monitoring data at home with the certified Type 3 monitor Nox-T3 and the Flow strain gauge sensor from SweetZpot. The quality of the Flow data does not match the quality of the Nox-T3 data due to the much simpler build of the Flow sensor and issues during data acquisition. The Flow data can still be used to accurately discriminate between normal and disrupted breathing. With appropriate data pre-processing, we achieve a mean breath detection sensitivity of 97.2% and positive prediction value of 94.2%.

• Volnes, Espen; Kristiansen, Stein & Plagemann, Thomas Peter (2021). Improving the Accuracy of Timing in Scalable WSN Simulations with Communication Software Execution Models. Computer Networks. ISSN 1389-1286. 188. doi: 10.1016/j.comnet.2021.107855.
• Nikolaidis, Konstantinos; Kristiansen, Stein; Goebel, Vera Hermine; Plagemann, Thomas Peter; Liestøl, Knut & Kankanhalli, Mohan (2020). Augmenting Physiological Time Series Data: A Case Study for Sleep Apnea Detection. I Koprinska, Irena (Red.), Workshops of the European Conference on Machine Learning and Knowledge Discovery in Databases (ECML PKDD 2020): SoGood 2020, PDFL 2020, MLCS 2020, NFMCP 2020, DINA 2020, EDML 2020, XKDD 2020 and INRA 2020). Springer. ISSN 978-3-030-65964-6. doi: 10.1007/978-3-030-46133-1_23.
• Zgheib, Rita; Kristiansen, Stein; Conchon, Emmanuel; Plagemann, Thomas Peter; Goebel, Vera Hermine & Bastide, Rémi (2020). A scalable semantic framework for IoT healthcare applications. Journal of Ambient Intelligence and Humanized Computing. ISSN 1868-5137. doi: 10.1007/s12652-020-02136-2.
• Kristiansen, Stein; Traaen, Gunn Marit; Øverland, Britt; Plagemann, Thomas Peter; Gullestad, Lars & Akre, Harriet [Vis alle 13 forfattere av denne artikkelen] (2020). Comparing manual and automatic scoring of sleep monitoring data from portable polygraphy. Journal of Sleep Research. ISSN 0962-1105. doi: 10.1111/jsr.13036. Fulltekst i vitenarkiv
• Volnes, Espen; Kristiansen, Stein; Plagemann, Thomas Peter; Goebel, Vera Hermine & Lindeberg, Morten Gunnar Bjørner (2019). Modeling the Software Execution of CEP in DCEP-Sim. I Koldehove, Boris (Red.), DEBS '19: Proceedings of the 13th ACM International Conference on Distributed and Event-based Systems 2019. ACM Publications. ISSN 978-1-4503-6794-3. s. 244–247. doi: https:/doi.org/10.1145/3328905.3332508.
• Volnes, Espen; Kristiansen, Stein & Plagemann, Thomas Peter (2019). Communication Software Execution Model of a WSN Device for More Accurate Simulation in ns-3. I Beydoun, Ghassan (Red.), Proceedings of The 11th International Conference on Computer Modeling and Simulation (ICCMS 2019). Association for Computing Machinery (ACM). ISSN 978-1-4503-6619-9. s. 184–189. doi: https:/doi.org/10.1145/3307363.3307371.
• Dale, Øystein; Kristiansen, Stein; Plagemann, Thomas Peter & Volnes, Espen (2019). Many Cores and Still Delays: Simulating Multi-Core Communication Software Execution. I Beydoun, Ghassan (Red.), Proceedings of The 11th International Conference on Computer Modeling and Simulation (ICCMS 2019). Association for Computing Machinery (ACM). ISSN 978-1-4503-6619-9. s. 171–175. doi: https:/doi.org/10.1145/3307363.3307384. Vis sammendrag

  The effects of software execution are typically ignored in network simulators. This leads to inaccurate simulation results for new and emerging network technologies where packet processing in software has a significant impact on network performance. In this paper we extend our prior work to develop models that capture the temporal aspects of software execution on both uni- and multi-core devices. When executed in parallel with existing network protocol models in network simulators, they significantly improve the accuracy of the simulation results. We demonstrate the applicability of the extended methodology by modeling the execution of communication software on one multi-core device, the Galaxy Nexus smartphone, and evaluate the resulting models in terms of accuracy and scalability. We find that our models are able to reproduce the behavior of the modeled software, and that the models scale well with the number of nodes, cores, and threads included in the simulation; i.e., the simulation overhead increases linearly with the number of nodes.

• Starks, Fabrice; Kristiansen, Stein & Plagemann, Thomas Peter (2018). DCEP-Sim: An Open Simulation Framework for Distributed CEP: Introduction for Users and Prospective Developers. I Hinze, Annika & Eyers, David (Red.), Proceedings of the 12th ACM International Conference on Distributed and Event-based Systems . Association for Computing Machinery (ACM). ISSN 978-1-4503-5782-1. s. 183–186. doi: 10.1145/3210284.3219501. Fulltekst i vitenarkiv Vis sammendrag

  Evaluation of Distributed Complex Event Processing (CEP) systems is a rather challenging task. To simplify this task, we developed the open simulation framework for Distributed CEP, called DCEP-Sim. The goal of this tutorial is to facilitate the process of using DCEP-Sim. Since DCEP-Sim is designed and implemented in the popular network simulator ns-3 we introduce the most important concepts of ns-3. Simulations in ns-3 are configured and executed though a main program called an ns-3 script. We use a simple example script to explain how simulations with DCEP-Sim are set up and executed. To give an idea how DCEP-Sim can be adjusted to particular needs, we explain how DCEP-Sim can be adapted (e.g., through changing the workload and the network topology) and how new Distributed CEP solutions can be added by explaining how to add a new operator to DCEP-Sim.

• Kristiansen, Stein; Sønsteby Hugaas, Mari; Goebel, Vera Hermine; Plagemann, Thomas Peter; Nikolaidis, Konstantinos & Liestøl, Knut (2018). Data Mining for Patient Friendly Apnea Detection. IEEE Access. ISSN 2169-3536. 6, s. 74598–74615. doi: 10.1109/ACCESS.2018.2882270. Fulltekst i vitenarkiv
• Fredrik, Løberg; Goebel, Vera Hermine & Plagemann, Thomas Peter (2018). Quantifying the Signal Quality of Low-cost Respiratory Effort Sensors for Sleep Apnea Monitoring. I Susanne, Boll; Ramesh, Jain; Noel, O'Connor; Troy, MacDaniel & Jochen, Meyer (Red.), Proceedings of the 3rd International Workshop on Multimedia for Personal Health and Health Care. ACM Digital Library. ISSN 978-1-4503-5982-5. s. 3–11. doi: 10.1145/3264996.3264998. Fulltekst i vitenarkiv Vis sammendrag

  Obstructive Sleep Apnea (OSA) is a common, but severely under- diagnosed sleep disorder characterized by recurring periods of shallow or paused breathing during sleep. It is our long-term goal to allow people to perform the first step towards a sleep apnea de- tection at home by utilizing smartphones, low-cost consumer-grade sensors, and data mining techniques. In this work, we evaluate the signal quality of four respiratory effort sensors (BITalino, FLOW, RespiBAN, and Shimmer), using a RIP sensor from NOX Medical as the gold standard. We design a sixteen-minute signal capture procedure to simulate epochs of disrupted breathing, and capture data from twelve (BITalino and Shimmer) and eleven (RespiBAN and FLOW) subjects during wakefulness. Our signal quality eval- uation approach is based on the breath detection accuracy met- rics sensitivity and positive predictive value (PPV), along with the breath amplitude accuracy metric weighted absolute percentage er- ror (WAPE). These metrics are closely related to how apneic and hypopneic episodes are scored by medical personnel, making it straightforward to reason about their interpretation. Our results show that false breaths are the primary concern affecting the breath detection accuracy of BITalino, Shimmer, and RespiBAN. Respec- tively, the sensitivity of BITalino, Shimmer, RespiBAN, and FLOW is 99.61%, 98.53%, 98.41%, and 98.91%. Their PPV is 96.28%, 96.58%, 90.81%, and 98.81%. Finally, their WAPE is 13.82%, 16.89%, 13.60%, and 8.75%. The supine (back) position is consistently showing the overall best signal quality compared to the side position.

• Kristiansen, Stein; Plagemann, Thomas Peter & Goebel, Vera Hermine (2018). An Activity Rule Based Approach to Simulate ADL Sequences. IEEE Access. ISSN 2169-3536. 6, s. 12551–12572. doi: 10.1109/ACCESS.2018.2807761. Fulltekst i vitenarkiv
• Starks, Fabrice; Goebel, Vera Hermine; Kristiansen, Stein & Plagemann, Thomas Peter (2018). Mobile Distributed Complex Event Processing - Ubi Sumus? Quo Vadimus? I Skourletopoulos, Georgios; Mastorakis, George; Mavromoustakis, Constandinos; Dobre, Ciprian & Pallis, Evangelos (Red.), Mobile Big Data: A Roadmap from Models to Technologies. Springer. ISSN 978-3-319-67924-2. s. 147–180. doi: 10.1007/978-3-319-67925-9_7. Vis sammendrag

  One important class of applications for the Internet of Things is related to the need to gain timely and continuous situational awareness, like smart cities, automated traffic control or emergency and rescue operations. Events happening in the real-world need to be detected in real-time based on sensor data and other data sources. Complex Event Processing (CEP) is a technology to detect complex (or composite) events in data streams and has been successfully applied in high volume and high velocity applications like stock market analysis. However, these applica- tion domains faced only the challenge of high performance, while the Internet of Things and Mobile Big Data introduce a new set of challenges caused by mobility. This chapter aims to explain these challenges and give an overview how they are solved respectively how far state-of-the-art research has advanced to be useful to solve mobile big data problems. At the infrastructure level the main challenge is to trade performance against resource consumption and energy efficiency and op- erator placement is the most dominant mechanisms to address these problems. At the application and consumer level mobile queries pose a new set of challenges for CEP related to continuously changing positions of consumers and producers and the need to adapt the query processing to these changes. Finally, methods and tools for systematical testing and reproducible performance evaluation for mobile distributed CEP is an open problem.

• Kristiansen, Stein; Goebel, Vera Hermine; Øyri, Karl & Plagemann, Thomas Peter (2018). Event-Based Methodology for Real-Time Data Analysis in Cyber Physical Systems. I Radek, Silhavy; Silhavy, Petr & Prokopova, Zdenka (Red.), Cybernetics Approaches in Intelligent Systems. Springer. ISSN 9783319676180. s. 184–195. doi: 10.1007/978-3-319-67618-0_17.
• Vatne Hansen, Hans; Goebel, Vera Hermine & Plagemann, Thomas Peter (2017). TRAMP Real-Time Application Mobility Platform. IEEE Transactions on Mobile Computing. ISSN 1536-1233. 16(11), s. 3236–3249. doi: 10.1109/TMC.2017.2688421.
• Cabrero, Sergio Cabrero; Pañeda, Xabiel Garcia; Melendi, David; Garcia, Roberto & Plagemann, Thomas Peter (2017). Using Firefighter Mobility Traces to Understand Ad-Hoc Networks in Wildfires. IEEE Access. ISSN 2169-3536. 6, s. 1331–1341. doi: 10.1109/ACCESS.2017.2778347.
• Starks, Fabrice; Kristiansen, Stein & Plagemann, Thomas Peter (2017). DCEP-Sim: An Open Simulation Framework for Distributed CEP. I Chandy, Mani & Koldehofe, Boris (Red.), The 11th ACM International Conference on Distributed and Event-Based Systems. ACM Digital Library. ISSN 978-1-4503-5065-5. s. 180–190. doi: 10.1145/3093742.3093919. Fulltekst i vitenarkiv
• Kristiansen, Stein; Plagemann, Thomas Peter & Goebel, Vera Hermine (2016). Smooth and crispy - integrating continuous event proximity calculation and discrete event detection. I Gal, Avigdor; Weidlich, Matthias; Kalogeraki, Vana & Venkasubramanian, Nalini (Red.), Proceedings of the 10th ACM International Conference on Distributed and Event-based Systems, DEBS '16, Irvine, CA,USA, June 20 -24. ACM Publications. ISSN 978-1-4503-4021-2. s. 153–160. doi: 10.1145/2933267.2933302.
• Vatne Hansen, Hans; Goebel, Vera Hermine & Plagemann, Thomas Peter (2016). DevCom: Device communities for user-friendly and trustworthy communication, sharing, and collaboration. Computer Communications. ISSN 0140-3664. 85, s. 14–27. doi: 10.1016/j.comcom.2016.02.001.
• Srebrny, Piotr; Sørbø, Dag Henning Liodden & Plagemann, Thomas Peter (2015). Tiny network caches with large performance gains for popular downloads. Lecture Notes in Computer Science (LNCS). ISSN 0302-9743. 9071, s. 197–210. doi: 10.1007/978-3-319-22572-2_14.
• Starks, Fabrice & Plagemann, Thomas Peter (2015). Operator placement for efficient distributed complex event processing in MANETs. IEEE International Conference on Wireless and Mobile Computing, Networking, and Communications. ISSN 2160-4886. s. 83–90. doi: 10.1109/WiMOB.2015.7347944.
• Dahl, Aage Andre Håland; Zaher, Ali & Plagemann, Thomas Peter (2015). Android Based Toolset for NFC Tag Testing and Performance Evaluation. I Badia, Leonardo (Red.), European Wireless 2015; 21th European Wireless Conference; Proceedings of. VDE Verlag GmbH. ISSN 978-3-8007-3976-9. s. 1–8.
• Kristiansen, Stein; Plagemann, Thomas Peter & Goebel, Vera Hermine (2015). A Methodology to Model the Execution of Communication Software for Accurate Network Simulation. ACM Transactions on Modeling and Computer Simulation. ISSN 1049-3301. 26(1). doi: 10.1145/2746233. Vis sammendrag

  Network simulation is commonly used to evaluate the performance of distributed systems, but these approaches do not account for the performance impact that protocol execution on nodes has on performance, which can be significant. We provide a methodology to extract from real devices models of communication software execution that can be used to extend network simulators to improve their accuracy. The models are obtained by instrumenting the target devices to obtain the events necessary to describe software execution. We specify which events must be captured, how to capture them, and how to transform the event traces into models that can be used to extend network simulators. The obtained models are based on high-level abstractions that can be used to describe the execution of a wide range of communication software, and the design principles to extend network simulators are not restricted to any specific network simulator. The same model of communication software execution can be used without modification in all discrete event-based network simulators that are extended according to our principles. The models are represented in a human-readable format that is suitable for modification and can therefore be used to predict how software modifications impact performance. We evaluate our models with two proof-of-concept extensions of Ns-3 that execute the models of two modern smartphones: the Google Nexus One (GN1) and the Nokia N900. We measure the accuracy of our models by comparing results from real experiments with those from simulations with our models and analyze the simulation overhead of our approach.

• Drugan, Ovidiu Valentin; Plagemann, Thomas Peter & Munthe-Kaas, Ellen (2015). Dynamic clustering in Sparse MANETs. Computer Communications. ISSN 0140-3664. 59, s. 84–97. doi: 10.1016/j.comcom.2014.12.005.
• Nguyen, Viet Hoang; Munthe-Kaas, Ellen & Plagemann, Thomas Peter (2014). Energy saving for activity recognition through sensor selection, scheduling and sampling rate tuning, 2014 7th IFIP Wireless and Mobile Networking Conference (WMNC). IEEE Press. ISSN 978-1-4799-3060-9. doi: 10.1109/WMNC.2014.6878873.
• Srebrny, Piotr; Sørbø, Dag Henning Liodden; Plagemann, Thomas Peter; Goebel, Vera Hermine & Mauthe, Andreas (2014). CacheCast: A Single-Source Multiple-Destination Caching Mechanism, Advanced Content Delivery, Streaming, and Cloud Services. Wiley. ISSN 9781118575215. s. 385–411. doi: 10.1002/9781118909690.ch20.
• Nguyen, Viet Hoang; Munthe-Kaas, Ellen & Plagemann, Thomas Peter (2013). Towards quality and energy aware complex event processing, Wireless and Mobile Computing, Networking and Communications (WiMob), 2013 IEEE 9th International Conference on. IEEE Press. ISSN 9781479904266. s. 352–359. doi: 10.1109/WiMOB.2013.6673384.
• Nguyen, Viet Hoang; Munthe-Kaas, Ellen & Plagemann, Thomas Peter (2013). Quality and energy aware data acquisition for activity and locomotion recognition, Pervasive Computing and Communications Workshops (PERCOM Workshops), 2013 IEEE International Conference on. IEEE Press. ISSN 978-1-4673-5075-4. s. 493–498. doi: 10.1109/PerComW.2013.6529547.
• Kristiansen, Stein; Plagemann, Thomas Peter & Goebel, Vera Hermine (2013). Extending network simulators with communication software execution models, 2013 Fifth International Conference on Communication Systems and Networks (COMSNETS). IEEE Press. ISSN 978-1-4673-5330-4. s. 1–10. doi: 10.1109/COMSNETS.2013.6465549.
• Kristiansen, Stein; Plagemann, Thomas Peter & Goebel, Vera Hermine (2013). Modeling communication software execution for accurate simulation of distributed systems, Proceedings of the 2013 ACM SIGSIM conference on Principles of advanced discrete simulation. Association for Computing Machinery (ACM). ISSN 978-1-4503-1920-1. s. 67–78. doi: 10.1145/2486092.2486102.
• Plagemann, Thomas Peter; Goebel, Vera Hermine; Mauthe, Andreas & Srebrny, Piotr (2013). No more Déjà Vu - Eliminating Redundancy with CacheCast: Feasibility and Performance Gains. IEEE/ACM Transactions on Networking. ISSN 1063-6692. 21(6), s. 1736–1749. doi: 10.1109/TNET.2012.2236104.
• Velazquez-Garcia, Francisco Javier; Andersen, Håvard Stigen; Vatne Hansen, Hans; Goebel, Vera Hermine & Plagemann, Thomas Peter (2013). SOCKMAN: Socket Migration for Multimedia Applications. I Pripužić, Krešimir & Banek, Marko (Red.), Proceedings of the 12th International Conference on Telecommunications. University of Zagreb. ISSN 978-953-184-175-7. s. 115–122.
• Kamisinski, Piotr; Goebel, Vera Hermine & Plagemann, Thomas Peter (2013). A reconfigurable distributed CEP middleware for diverse mobility scenarios. I Indulska, Jadwiga & Bisdikian, Chatschik (Red.), 2013 IEEE International Conference on Pervasive Computing and Communications Workshops. IEEE (Institute of Electrical and Electronics Engineers). ISSN 978-1-4673-5077-8. s. 617–620. doi: 10.1109/PerComW.2013.6529568.
• Rodriguez-Fernandez, Daniel ; Martinez-Yelmo, Isaias; Munthe-Kaas, Ellen & Plagemann, Thomas Peter (2012). ILORIN: Identifier-LOcator Resolution for Infrastructure-less Networks. I Pujolle, Guy; Duarte, Otto & Boutaba, Raouf (Red.), Proceedings of the 2012 International Conference on the Network of the Future (NoF'12). IEEE conference proceedings. ISSN 978-1-4673-5265-9. doi: 10.1109/nof.2012.6463992. Vis sammendrag

  In order to overcome the limitations of the current Internet addressing, it is generally accepted that the Future Internet needs a separation between identifiers and network locators. Such identifier-locator split is also needed in infrastructure-less networks, such as Mobile ad hoc Networks (MANETs) and Delay Tolerant Networks, since they are an integral part of the Future Internet. Despite the amount of work in infrastructure-based networks, only a few proposals have considered how to apply this identifier-locator split in infrastructure-less networks. The contribution of this paper is an identifier-locator resolution system that can work in sparse MANETs, which are prone to network partitions. Our approach is an identifier-locator association discovery system, which uses periodic beacons to exchange the resolution information, avoiding the establishment of shared state between nodes. Our system exploits the broadcast nature of the wireless medium, opportunistic encounters, and information replication to disseminate identifier-locator associations across the network. The results of our extensive experiments demonstrate that our solution outperforms the related work, achieving a higher identifier-locator association discovery rate. association discovery system, which uses periodic beacons to exchange the resolution information, avoiding the establishment of shared state between nodes. Our system exploits the broadcast nature of the wireless medium, opportunistic encounters, and information replication to disseminate identifier-locator associations across the network. The results of our extensive experiments demonstrate that our solution outperforms the related work, achieving a higher identifier-locator association discovery rate.

• Lindeberg, Morten Gunnar Bjørner; Goebel, Vera Hermine & Plagemann, Thomas Peter (2012). CLiSuite: Simplifying the development of cross-layer adaptive applications. I Göschka, Karl M.; Tosic, Vladimir; Pereira, José Orlando & Hung, Patrick C. K. (Red.), Proceedings of the 7th Workshop on Middleware for Next Generation Internet Computing (MW4NG '12). Association for Computing Machinery (ACM). ISSN 978-1-4503-1607-1. s. 1–6. doi: 10.1145/2405178.2405180.
• Lindeberg, Morten Gunnar Bjørner; Haavet, Jan Erik; Barros, Sergio Cabrero; Goebel, Vera Hermine & Plagemann, Thomas Peter (2012). Message lost or message taken - on message ferry selection in DTNs -. I Fitzpatrick, John M. (Red.), Wireless Days (WD) 2012 Conference Publications. IEEE conference proceedings. ISSN 978-1-4673-4402-9. s. 1–7. doi: 10.1109/wd.2012.6402815.
• Cabrero, Sergio; Paneda, Xabiel G.; Gracia, Roberto; Melendi, David & Plagemann, Thomas Peter (2012). Dynamic Temporal Scalability: Video adaptation in sparse Mobile Ad-Hoc Networks. I Barcelo-Ordinas, Jose M.; Chen, Wen & Quintero, Alejandro (Red.), Wireless and Mobile Computing, Networking and Communications (WiMob), 2012 IEEE 8th International Conference on. IEEE conference proceedings. ISSN 978-1-4673-1429-9. s. 349–356. doi: 10.1109/wimob.2012.6379097.
• Tyson, Gareth; Mauthe, Andreas; Kaune, Sebastian; Grace, Paul; Taweel, Adel & Plagemann, Thomas Peter (2012). Juno: An Adaptive Delivery-Centric Middleware. I Shirazi, Behrooz (Red.), Consumer Communications and Networking Conference (CCNC), 2012 IEEE. IEEE Sarnoff Symposium. ISSN 978-1-4577-2071-0. s. 587–591. doi: 10.1109/ccnc.2012.6181010.
• Tyson, Gareth; Mauthe, Andreas; Kaune, Sebastian; Grace, Paul; Taweel, Adel & Plagemann, Thomas Peter (2012). Juno: a middleware platform for supporting delivery-centric applications. ACM Transactions on Internet Technology. ISSN 1533-5399. 12(2). doi: 10.1145/2390209.2390210.
• Nguyen, Viet Hoang; Munthe-Kaas, Ellen & Plagemann, Thomas Peter (2012). Energy-balanced sensor selection for social context detection. I Giordano, Silvia; Langheinrich, Marc & Schmidt, Albrecht (Red.), 2012 IEEE International Conference on Pervasive Computing and Communications Workshops. IEEE (Institute of Electrical and Electronics Engineers). ISSN 978-1-4673-0905-9. s. 32–37.
• Hansen, Hans Vatne; Velazquez, Francisco Javier; Goebel, Vera Hermine & Plagemann, Thomas Peter (2012). Efficient Data Sharing for Multi-device Multimedia Applications. I Fuhrhop, Christian; Steglich, Stephan & Jaokar, Ajit (Red.), Proceedings of the Workshop on Multi-device App Middleware, Multi-Device '12. Association for Computing Machinery (ACM). ISSN 978-1-4503-1617-0. doi: 10.1145/2405172.2405174.
• Hansen, Hans Vatne; Velazquez-Garcia, Francisco Javier; Goebel, Vera Hermine; Munthe-Kaas, Ellen & Plagemann, Thomas Peter (2012). Migration of Fine-grained Multimedia Applications. I Wohlstadter, Eric (Red.), Proceedings of the Posters and Demo Track, Middleware '12. Association for Computing Machinery (ACM). ISSN 978-1-4503-1612-5. doi: 10.1145/2405153.2405165.
• Rodriguez-Fernandez, Daniel ; Martinez-Yelmo, Isaias; Munthe-Kaas, Ellen & Plagemann, Thomas Peter (2012). Always best (dis-)connected: challenges to interconnect highly heterogeneous networks. Journal of Internet Engineering. ISSN 1791-177X. 5(1), s. 299–309. Vis sammendrag

  Wireless networks enable mobility, multihoming, and Delay Tolerant Networks. In such networking environments, the principles of the Internet, i.e., the end-to-end principle and the combination of identity and location in IP addresses, cannot be applied. In this paper, we propose a scalable application centric approach for supporting mobility, multihoming, and interconnecting highly heterogeneous networks where the networks may belong to different networking paradigms, e.g., IP based and Delay Tolerant Networks. Applications and users that want to communicate, use communities. These communities are application specific overlays formed by entities (nodes or other communities) that want to support the application. Community members might together have several network technologies available, and the community manages internetworking information for the members to seamlessly integrate them. This integration is assisted by a community support layer that coordinates the communities with the available networks. An underlay layer common interface is used to access the different networks, allowing an implementation that considers its specific characteristics and challenges. We propose a global cryptographic based namespace for entities to enable internetworking across heterogeneous networks with different locator schemes. Identifiers are resolved to locators using a late binding approach. Furthermore, we analyse the communication challenges present in emergency and rescue operations and describe how to deal with them using our proposal.

• Cabrero, Sergio; Pañeda, Xabiel Garcia; Plagemann, Thomas Peter; Melendi, David & Garcia, Roberto (2011). Towards reliable video transmission over sparse MANETs in emergencies. Informática na educação: teoria & prática. ISSN 1516-084X. 14(1), s. 61–77. doi: 10.22456/1982-1654.21937.
• Søberg, Jarle; Goebel, Vera Hermine & Plagemann, Thomas Peter (2011). Deviation detection in automated home care using CommonSens, 2011 IEEE International Conference on Pervasive Computing and Communications Workshops (PERCOM Workshops). IEEE (Institute of Electrical and Electronics Engineers). ISSN 978-1-61284-938-6. s. 668–673. doi: 10.1109/percomw.2011.5766972. Vis sammendrag

  Automated home care uses sensors to report about the well-being of monitored persons. Our complex event processing (CEP) system CommonSens simplifies the work of the application programmers, i.e., those who write the complex queries, by facilitating reuse of queries, sensor instances and environments. We have observed that many automated home care systems focus on detecting alarming behaviour, e.g., falls and heart attacks. However, it is impossible to predict and describe everything that can go wrong. In this paper we define deviation detection in CommonSens, which means that the application programmer only needs to state queries that define correct behaviour. If something happens that does not correspond to the query, this is interpreted as a deviation and a notification or alarm is sent. We believe that this approach further simplifies the work of the application programmer. Deviation detection is implemented in our CommonSens prototype, and we show that our prototype detects deviations as expected by running a set of functionality tests and an experiment based on real-world trace files.

• Puzar, Matija & Plagemann, Thomas Peter (2011). Data sharing in mobile ad-hoc networks – a study of replication and performance in the MIDAS data space. International Journal of Space-Based and Situated Computing (IJSSC). ISSN 2044-4893. 1(2-3), s. 137–150. doi: 10.1504/IJSSC.2011.04034.
• Mondet, Sebastien; Alberdi, Ion & Plagemann, Thomas Peter (2011). Generating Optimised and Formally Checked Packet Parsing Code, Future Challenges in Security and Privacy for Academia and Industry 26th IFIP TC 11 International Information Security Conference. Springer. ISSN 978-3-642-21423-3. s. 173–184. doi: 10.1007/978-3-642-21424-0_14.
• Kristiansen, Stein; Plagemann, Thomas Peter & Goebel, Vera (2011). Towards scalable and realistic node models for network simulators. I Keshav, Srinivasan; Liebeherr, Jörg; Byers, John & Mogul, Jeffrey (Red.), Proceedings of the ACM SIGCOMM 2011 conference on SIGCOMM. Association for Computing Machinery (ACM). ISSN 978-1-4503-0797-0. s. 418–419. doi: 10.1145/2043164.2018498.
• Lindeberg, Morten Gunnar Bjørner; Kristiansen, Stein; Plagemann, Thomas Peter & Goebel, Vera (2011). Challenges and techniques for video streaming over mobile ad hoc networks. Multimedia Systems. ISSN 0942-4962. 17(1), s. 51–82. doi: 10.1007/s00530-010-0187-8.
• Drugan, Ovidiu Valentin; Plagemann, Thomas Peter & Munthe-Kaas, Ellen (2011). Detecting Communities in Sparse MANETs. IEEE/ACM Transactions on Networking. ISSN 1063-6692. 19(5), s. 1434–1447. doi: 10.1109/TNET.2011.2112376.
• Kristiansen, Stein & Plagemann, Thomas Peter (2011). Accuracy and scalability of ns-2's distributed emulation extension. Simulation (San Diego, Calif.). ISSN 0037-5497. 87(1-2), s. 45–65. doi: 10.1177/0037549710370215.
• Rodriguez-Fernandez, Daniel ; Akø, Per-Arne Holtmon & Plagemann, Thomas Peter (2011). Leveraging self-description to visualise autonomic networks. I Schmeck, Hartmut; Rosenstiel, Wolfgang; Abdelzaher, Tarek & Hellerstein, Joseph (Red.), ICAC '11 8th International Conference on Autonomic Computing Karlsruhe, Germany — June 14 - 18, 2011. Association for Computing Machinery (ACM). ISSN 978-1-4503-0607-2. s. 183–184. doi: 10.1145/1998582.1998619. Vis sammendrag

  The ANA (Autonomic Networking Architecture) project provides a framework to design, create, and federate different network architectures. ANA considers that different network paradigms require their own network architecture and internal policies. The present work describes how the self-description property of autonomic systems is used by the ANA Browser visualisation tool to allow a human user to inspect how an ANA network works internally. The ANA BrowseThe ANA (Autonomic Networking Architecture) project provides a framework to design, create, and federate different network architectures. ANA considers that different network paradigms require their own network architecture and internal policies. The present work describes how the self-description property of autonomic systems is used by the ANA Browser visualisation tool to allow a human user to inspect how an ANA network works internally. The ANA Browser extends the classical network visualisation with a description of the functional configuration which may vary considerably amongst different ANA networks and also might vary at run-time on such polymorphic networks.r extends the classical network visualisation with a description of the functional configuration which may vary considerably amongst different ANA networks and also might vary at run-time on such polymorphic networks.

• Rodriguez-Fernandez, Daniel ; Martinez, Isaias; Munthe-Kaas, Ellen & Plagemann, Thomas Peter (2011). Always Best (dis-)Connected: Challenges to Interconnect Highly Heterogeneous Networks. I Masip-Bruin, Xavier; Verchere, Dominique; Tsaoussidis, Vassilis & Yannuzzi, Marcelo (Red.), Wired/Wireless Internet Communications: 9th IFIP TC 6 International Conference, WWIC 2011, Vilanova i la Geltrú, Spain, June 15-17, 2011, Proceedings. Springer. ISSN 978-3-642-21559-9. s. 410–421. doi: 10.1007/978-3-642-21560-5_34. Vis sammendrag

  Wireless networks enable mobility, multihoming, and Delay Tolerant Networks. In such networking environments, the principles of the Internet, i.e., the end-to-end principle and the combination of location and identification in IP addresses, cannot be applied. In this paper, we propose a scalable application centric approach for mobility and multihoming that is able to interconnect highly heterogeneous networks where the networks may belong to different networking paradigms, e.g., IP based and Delay Tolerant Networks. Applications and users that aim to communicate, form communities. Community members might together have several network technologies available, and the community layer manages internetworking information for the members to seamlessly integrate these. Networking adaptation layers are used to provide a common interface for the different networks to the community layer. Addressing is based on names, cryptographic identifiers, and network locators and such that identifiers can also be created in infrastructure-less and disconnected situations.

• Lindeberg, Morten Gunnar Bjørner; Kristiansen, Stein; Goebel, Vera Hermine & Plagemann, Thomas Peter (2011). MAC Layer Support for Delay Tolerant Video Transport in Disruptive MANETs. I Domingo-Pascual, Jordi (Red.), Proceedings, Part I of the10th International IFIP TC 6 Networking Conference (NETWORKING 2011), Valencia, Spain, May 9-13, 2011. Springer. ISSN 978-3-642-20756-3. s. 106–119. doi: 10.1007/978-3-642-20757-0_9.
• Kristiansen, Stein; Plagemann, Thomas Peter & Goebel, Vera Hermine (2011). Towards Scalable and Realistic Node Models for Network Simulators. Computer communication review. ISSN 0146-4833. 41(4), s. 418–419. doi: 10.1145/2043164.2018498.
• Rodriguez-Fernandez, Daniel ; Martinez-Yelmo, Isaias; Munthe-Kaas, Ellen & Plagemann, Thomas Peter (2011). Always Best (dis-)Connected: Challenges to Interconnect Highly Heterogeneous Networks. Lecture Notes in Computer Science (LNCS). ISSN 0302-9743. 6649, s. 410–421.
• Skjelsvik, Katrine S; Goebel, Vera Hermine & Plagemann, Thomas Peter (2010). Event-Based Interaction for Rescue and Emergency Applications in Mobile and Disruptive Environments. I Hinze, Annika & Buchmann, Alejandro (Red.), Principles and Applications of Distributed Event-Based Systems. Information Science Reference. ISSN 978-160566697-6. s. 411–431.
• Kristiansen, Stein & Plagemann, Thomas Peter (2010). Accuracy and scalability of ns-2’s distributed emulation extension. Simulation (San Diego, Calif.). ISSN 0037-5497. 87(1), s. 45–65. doi: 10.1177/0037549710370215.
• Srebrny, Piotr; Plagemann, Thomas Peter; Goebel, Vera Hermine & Mauthe, Andreas (2010). CacheCast: Eliminating Redundant Link Traffic for Single Source Multiple Destination Transfers. Distributed Computing Systems. ISSN 1063-6927. doi: 10.1109/ICDCS.2010.29.
• Søberg, Jarle; Goebel, Vera Hermine & Plagemann, Thomas Peter (2010). CommonSens: Personalisation of Complex Event Processing in Automated Homecare. I Marusic, Slaven (Red.), Proceedings of the 2010 Sixth International Conference on Intelligent Sensors, Sensor Networks and Information Processing. IEEE conference proceedings. ISSN 978-1-4244-7176-8. s. 275–280.
• Søberg, Jarle; Goebel, Vera Hermine & Plagemann, Thomas Peter (2010). Detection of spatial events in CommonSens. I Scherp, Ansgar (Red.), Proceedings of the 2nd ACM international workshop on Events in multimedia. Association for Computing Machinery (ACM). ISSN 978-1-4503-0176-3. s. 53–58.
• Puzar, Matija & Plagemann, Thomas Peter (2010). Evaluation of Replica Placement Strategies for a Shared Data Space in Mobile Ad-Hoc Network. I Bilof, Randall (Red.), NBiS 2010 13th International Conference on Network-Based Information Systems. IEEE conference proceedings. ISSN 978-0-7695-4167-9. s. 232–239.
• Lindeberg, Morten Gunnar Bjørner; Goebel, Vera Hermine & Plagemann, Thomas Peter (2010). Adaptive sized windows to improve real-time health monitoring: a case study on heart attack prediction. I Wang, James Z. (Red.), Proceedings of the international conference on Multimedia information retrieval. Association for Computing Machinery (ACM). ISSN 978-1-60558-815-5. s. 459 –468.
• Hansen, Hans Vatne; Goebel, Vera Hermine; Plagemann, Thomas Peter & Siekkinen, Matti Mikael (2010). Resource Adaptive Distributed Information Sharing. I Aagesen, Finn Arve & Knapskog, Svein Johan (Red.), Networked Services and Applications - Engineering, Control and Management. Springer. ISSN 978-3-642-13970-3. s. 246–255.
• Kristiansen, Stein; Lindeberg, Morten Gunnar Bjørner; Rodriguez-Fernandez, Daniel & Plagemann, Thomas Peter (2010). On the forwarding capability of mobile handhelds for video streaming over MANETs. I Cox, Landon & Wolman, Alec (Red.), Proceedings of the second ACM SIGCOMM workshop on Networking, systems, and applications on mobile handhelds (MobiHeld 2010). Association for Computing Machinery (ACM). ISSN 978-1-4503-0197-8. s. 33 –38.
• Lindeberg, Morten Gunnar Bjørner; Kristiansen, Stein; Plagemann, Thomas Peter & Goebel, Vera Hermine (2010). Challenges and techniques for video streaming over mobile ad hoc networks. Multimedia Systems. ISSN 0942-4962. doi: 10.1007/s00530-010-0187-8.
• Rodriguez-Fernandez, Daniel ; Skevik, Karl Andre; Goebel, Vera Hermine & Plagemann, Thomas Peter (2009). Demonstrating Autonomic On-Demand Content Delivery. I Mauthe, Andreas; Zeadally, Sherali; Cerqueira, Eduardo & Curado, Marilia (Red.), Future Multimedia Networking, 2nd Int. Workshop, FMN 2009. Springer. ISSN 3-642-02471-8. s. 206–211.
• Cabrero, Sergio; Xabiel, Paneda; Plagemann, Thomas Peter; Goebel, Vera Hermine & Siekkinen, Matti (2009). Overlay solution for multimedia data over sparse MANETs. I Guizani, Mohsen; Mueller, Peter; Fähnrich, Klaus-Peter; Vasilakos, Athanasios; Zhang, Yan & Zhang, Jun (Red.), Proceedings of the 2009 International Conference on Wireless Communications and Mobile Computing: Connecting the World Wirelessly. Association for Computing Machinery (ACM). ISSN 978-1-60558-569-7. s. 1056–1061.
• Kristiansen, Stein & Plagemann, Thomas Peter (2009). ns-2 distributed clients emulation: accuracy and scalability. I Dalle, Olivier; Wainer, Gabriel A.; Perrone, Luiz Felipe & Stea, Giovanni (Red.), Proceedings of the 2nd International Conference on Simulation Tools and Techniques for Communications, Networks and Systems, SimuTools 2009. ICST. ISSN 978-963-9799-45-5. s. 1–10. Fulltekst i vitenarkiv

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• Plagemann, Thomas Peter (2023). Opportunities and Challenges of using Smart Devices and Machine Learning for Health Applications.
• Plagemann, Thomas Peter (2023). Responsible Explainable Machine Learning for Sleep-related Respiratory Disorders.
• Plagemann, Thomas Peter (2023). Respire - planlegging og gjennomføring av internasjonale samarbeidsprosjekter,
• Plagemann, Thomas Peter (2023). Semantic and utility aware operator migration for Distributed Stream Processing.
• Goebel, Vera Hermine & Plagemann, Thomas Peter (2022). Respire - Responsible Explainable Machine Learning for Sleep-related Respiratory Disorders.
• Plagemann, Thomas Peter (2019). Special issues on “User-Centric Social Multimedia Computing” and “Multimedia Cloud Computing for Smarter Cities”. Multimedia Systems. ISSN 0942-4962. 25(5). doi: 10.1007/s00530-019-00634-8.
• Nikolaidis, Konstantinos; Kristiansen, Stein; Goebel, Vera Hermine; Plagemann, Thomas Peter & Liestøl, Knut (2019). Augmenting Physiological Time Series Data: A Case study for Sleep Apnea Detection.
• Volnes, Espen; Kristiansen, Stein; Plagemann, Thomas Peter; Goebel, Vera Hermine & Lindeberg, Morten Gunnar Bjørner (2019). Modeling the Software Execution of CEP in DCEP-Sim.
• Volnes, Espen; Kristiansen, Stein & Plagemann, Thomas Peter (2019). Communication Software Execution Model of a WSN Device for More Accurate Simulation in ns-3.
• Dale, Øystein; Kristiansen, Stein; Plagemann, Thomas Peter & Volnes, Espen (2019). Many Cores and Still Delays: Simulating Multi-Core Communication Software Execution. Vis sammendrag

  The effects of software execution are typically ignored in network simulators. This leads to inaccurate simulation results for new and emerging network technologies where packet processing in software has a significant impact on network performance. In this paper we extend our prior work to develop models that capture the temporal aspects of software execution on both uni- and multi-core devices. When executed in parallel with existing network protocol models in network simulators, they significantly improve the accuracy of the simulation results. We demonstrate the applicability of the extended methodology by modeling the execution of communication software on one multi-core device, the Galaxy Nexus smartphone, and evaluate the resulting models in terms of accuracy and scalability. We find that our models are able to reproduce the behavior of the modeled software, and that the models scale well with the number of nodes, cores, and threads included in the simulation; i.e., the simulation overhead increases linearly with the number of nodes.

• Wang, Meng; Tie, Yun; Tian, Qi; Saddik, Abdulmotaleb Ei; Gong, Yihong & Plagemann, Thomas Peter [Vis alle 8 forfattere av denne artikkelen] (2016). Preface. Lecture Notes in Computer Science (LNCS). ISSN 0302-9743. 9917 LNCS, s. V–VI.
• Wang, Meng; Tie, Yun; Tian, Qi; Saddik, Abdulmotaleb Ei; Gong, Yihong & Plagemann, Thomas Peter [Vis alle 8 forfattere av denne artikkelen] (2016). Preface. Lecture Notes in Computer Science (LNCS). ISSN 0302-9743. 9916 LNCS, s. V–VI.
• Fabrice, Bigirimana; Goebel, Vera Hermine & Plagemann, Thomas Peter (2014). Investigation of contradicting optimization goals for event processing overlays in MANETs.
• Cabrero, Sergio; Xabiel, Paneda; Plagemann, Thomas Peter; Melendi, David & Garcia, Roberto (2011). An Overlay Routing Protocol for Video over sparse MANETs in Emergencies.
• Kamisinski, Piotr; Mondet, Sebastien; Plagemann, Thomas Peter & Goebel, Vera Hermine (2010). Resource-Aware Complex Event Processing for Mobile Ubiquitous Environments.
• Volnes, Espen; Plagemann, Thomas Peter & Goebel, Vera Hermine (2022). To Migrate or not to Migrate: An Analysis of Operator Migration in Distributed Stream Processing. arXiv2022. Vis sammendrag

  One of the most important issues in data stream processing systems is to use operator migration to handle highly variable workloads in a cost-efficient manner and adapt to the needs at any given time on demand. Operator migration is a complex process that involves changes in the state and stream management of a running query, typically without any loss of data, and with as little disruption to the execution as possible. This survey provides an overview of solutions for operator migration from a historical perspective as well as the perspective of the goal of migration. It introduces a conceptual model of operator migration to establish a unified terminology and classify existing solutions. Existing work in the area is analyzed to separate the mechanism of migration from the decision to migrate the data. In case of the latter, a cost-benefit analysis is emphasized that is important for operator migration but is often only implicitly addressed, or is neglected altogether. A description of the available solutions provides the reader with a good understanding of the design alternatives from an algorithmic viewpoint. We complement this with an empirical study to provide quantitative insights on the impact of different design alternatives on the mechanisms of migration

• Plagemann, Thomas Peter; Goebel, Vera Hermine; Hollick, Matthias & Koldehofe, Boris (2022). Towards Privacy Engineering for Real-Time Analytics in the Human-Centered Internet of Things. arXiv. Vis sammendrag

  Big data applications offer smart solutions to many urgent societal challenges, such as health care, traffic coordination, energy management, etc. The basic premise for these applications is "the more data the better". The focus often lies on sensing infrastructures in the public realm that produce an ever-increasing amount of data. Yet, any smartphone and smartwatch owner could be a continuous source of valuable data and contribute to many useful big data applications. However, such data can reveal a lot of sensitive information, like the current location or the heart rate of the owner of such devices. Protection of personal data is important in our society and for example manifested in the EU General Data Protection Regulation (GDPR). However, privacy protection and useful big data applications are hard to bring together, particularly in the human-centered IoT. Implementing proper privacy protection requires skills that are typically not in the focus of data analysts and big data developers. Thus, many individuals tend to share none of their data if in doubt whether it will be properly protected. There exist excellent privacy solutions between the "all or nothing" approach. For example, instead of continuously publishing the current location of individuals one might aggregate this data and only publish information of how many individuals are in a certain area of the city. Thus, personal data is not revealed, while useful information for certain applications like traffic coordination is retained. The goal of the Parrot project is to provide tools for real-time data analysis applications that leverage this "middle ground". Data analysts should only be required to specify their data needs, and end-users can select the privacy requirements for their data as well as the applications and end-users they want to share their data with.

• Starks, Fabrice; Goebel, Vera Hermine; Kristiansen, Stein & Plagemann, Thomas Peter (2017). Mobile Distributed Complex Event Processing - Ubi Sumus? Quo Vadimus? Universitetet i Oslo. ISSN 978-82-7368-429-5. Fulltekst i vitenarkiv
• Kristiansen, Stein; Goebel, Vera Hermine; Øyri, Karl & Plagemann, Thomas Peter (2017). Event Modeling and Processing to Simplify Real-Time Analysis of Physiological Signals. Universitetet i Oslo. ISSN 978-82-7368-428-8. Fulltekst i vitenarkiv
• Rodriguez-Fernandez, Daniel ; Kristiansen, Stein; Lindeberg, Morten Gunnar Bjørner; Drugan, Ovidiu Valentin; Cabrero, Sergio & Plagemann, Thomas Peter [Vis alle 9 forfattere av denne artikkelen] (2012). Delay Tolerant Streaming in Rescue Scenarios: Requirements Analysis and Resulting Industrial Issues - Version 2. Universitetet i Oslo. ISSN 82-7368-382-6. Fulltekst i vitenarkiv Vis sammendrag

  In emergency intervention and rescue operations, the coordination and collaboration of the rescue personnel is highly important for the success of the mission. Data networks formed between the devices carried by the rescue personnel can provide the means for collaboration and coordination on the operation scene. Unfortunately, the unforeseeable conditions and characteristics (e.g., size of the scene, availabilities of access ways for the rescue personnel, availability and status of the infrastructure) of the rescue operations can hinder (e.g., intermittently unavailable network infrastructure) and disrupt (e.g., network partitions) communication of data networks. Even in these adverse conditions coordination and collaboration need to be enabled between the participants of the rescue operation. In this technical report we analyse the usage of streaming services (data, audio and video) to improve coordination and collaboration tasks in rescue and emergency operations. We present a detailed requirement analysis for middleware services that support streaming of data, imposed by this application domain from a research and an industrial perspective. For this purpose, we present two rescue scenarios, which helped us perform the requirements analysis for supporting streaming in intermittently connected networks. Additionally, we also present an example from a middleware for streaming voice traffic within large organizations with multiple working sites. Although these examples might seem different, they have similar requirements considering the availability and awareness of network resources.

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