• CSP at the Cyber-Physical Edge 

      Michalik, Lukasz Sergiusz; Murphy, Michael J.; Bjørndalen, John Markus; Anshus, Otto (Chapter; Bokkapittel, 2019)
      Today, to do ground-based in-situ observations of the arctic tundra, researchers carry wild life cameras and other observation units into the field, manually configure the devices while on the arctic tundra, and fetch the collected data several months later. This approach does not scale. Instead, observing and reporting of data must be automated using a distributed wireless network of autonomous ...
    • DeltaTree: A Locality-aware Concurrent Search Tree 

      Umar, Ibrahim; Anshus, Otto; Ha, Hoai Phuong (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-06-15)
      Like other fundamental abstractions for high-performance computing, search trees need to support both high concurrency and data locality. However, existing locality-aware search trees based on the van Emde Boas layout (vEB-based trees), poorly support concurrent (update) operations. We present DeltaTree, a practical locality-aware concurrent search tree that integrates both locality-optimization ...
    • DeltaTree: A Practical Locality-aware Concurrent Search Tree 

      Umar, Ibrahim; Anshus, Otto; Ha, Hoai Phuong (Research report; Forskningsrapport, 2013)
      As other fundamental programming abstractions in energy-e cient computing, search trees are expected to support both high parallelism and data locality. However, existing highly-concurrent search trees such as red-black trees and AVL trees do not consider data locality while existing locality-aware search trees such as those based on the van Emde Boas layout (vEB-based trees), poorly support ...
    • Efficient concurrent search trees using portable fine-grained locality 

      Ha, Hoai Phuong; Anshus, Otto; Umar, Ibrahim (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-01-14)
      Concurrent search trees are crucial data abstractions widely used in many important systems such as databases, file systems and data storage. Like other fundamental abstractions for energy-efficient computing, concurrent search trees should support both high concurrency and fine-grained data locality in a platform-independent manner. However, existing portable fine-grained locality-aware search trees ...
    • Embarrassingly Distributed Computing for Symbiotic Weather Forecasts 

      Fjukstad, Bård; Bjørndalen, John Markus; Anshus, Otto (Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
    • Experiences Building and Deploying Wireless Sensor Nodes for the Arctic Tundra 

      Murphy, Michael J.; Tveito, Øystein; Kleiven, Eivind Flittie; Rais, Issam; Soininen, Eeva M; Bjørndalen, John Markus; Anshus, Otto (Journal article; Tidsskriftartikkel, 2021-08-02)
      The arctic tundra is most sensitive to climate change. The change can be quantified from observations of the fauna, flora and weather conditions. To do observations at sufficient spatial and temporal resolution, ground-based observation nodes with sensors are needed. However, the arctic tundra is resource-limited with regards to energy, data networks, and humans. There are also regulatory and practical ...
    • Experimental Fault-Tolerant Synchronization for Reliable Computation on Graphics Processors 

      Hagen, Tor-Magne Stien; Ha, Hoai Phuong; Anshus, Otto (Research report; Forskningsrapport, 2012)
      Graphics processors (GPUs) are emerging as a promising platform for highly parallel, compute-intensive, general-purpose computations, which usually need support for inter-process synchronization. Using the traditional lock-based synchronization (e.g. mutual exclusion) makes the computation vulnerable to faults caused by both scientists’ inexperience and hardware transient errors. It is notoriously ...
    • Flexible Devices for Arctic Ecosystems Observations 

      Michalik, Lukasz Sergiusz; Anshus, Otto; Bjørndalen, John Markus (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-11-26)
      <p>Devices for observing the environment range from basic sensor systems, like step-counters, through wild-life cameras, with limited processing capabilities, to more capable devices with significant processing, memory and storage resources. Individual usage domains can benefit from a range of functionalities in these devices including flexibility in prototyping, on- device analytics, network roaming, ...
    • Gesture-Based, Touch-Free Multi-User Gaming on Wall-Sized, High-Resolution Tiled Displays 

      Stødle, Daniel; Hagen, Tor-Magne Stien; Bjørndalen, John Markus; Anshus, Otto (Journal article; Tidsskriftartikkel; Peer reviewed, 2008)
    • GreenBST: Energy-efficient concurrent search tree 

      Umar, Ibrahim; Anshus, Otto; Ha, Hoai Phuong (Conference object; Konferansebidrag, 2016-08-09)
      Like other fundamental abstractions for energy-efficient com- puting, search trees need to support both high concurrency and fine- grained data locality. However, existing locality-aware search trees such as ones based on the van Emde Boas layout (vEB-based trees), poorly support concurrent (update) operations while existing highly-concurrent search trees such as the non-blocking binary search ...
    • Masking the Effects of Delays in Human-to-Human Remote Interaction 

      Su, Fei; Bjørndalen, John Markus; Ha, Hoai Phuong; Anshus, Otto (Chapter; Bokkapittel, 2014)
      Humans can interact remotely with each other through computers. Systems supporting this include teleconferencing, games and virtual environments. There are delays from when a human does an action until it is reflected remotely. When delays are too large, they will result in inconsistencies in what the state of the interaction is as seen by each participant. The delays can be reduced, but they cannot ...
    • MultiStage: Acting across Distance 

      Su, Fei; Tartari, Giacomo; Bjørndalen, John Markus; Ha, Hoai Phuong; Anshus, Otto (Conference object; Konferansebidrag, 2013)
      We report on a prototype system helping actors on a stage to interact and perform with actors on other stages as if they were on the same stage. At each stage four 3D cameras tiled back to back for an almost 360 degree view, continuously record actors. The system processes the recorded data on-the-fly to discover actions by actors that it should react to, and it streams data about actors and their ...
    • pVD - Personal Video Distribution 

      Su, Fei; Bjørndalen, John Markus; Ha, Hoai Phuong; Anshus, Otto (Journal article; Tidsskriftartikkel, 2013-11-25)
      A user has several personal computers, including mobile phones, tablets, and laptops, and needs to watch live camera feeds from and videos stored at any of these computers at one or more of the others. Industry solutions designed for many users, computers, and videos can be complicated and slow to apply. The user must typically rely on a third party service or at least log in. The Personal Video ...
    • Scalability of Distributed Version Control Systems 

      Murphy, Mike; Bjørndalen, John Markus; Anshus, Otto (Journal article; Tidsskriftartikkel, 2017-11-26)
      <p>Distributed version control systems are popular for storing source code, but they are notoriously ill suited for storing large binary files. <p>We report on the results from a set of experiments designed to characterize the behavior of some widely used distributed version control systems with respect to scaling. The experiments measured commit times and repository sizes when storing single files ...
    • Uncertainty Estimation and Visualization of Wind in Weather Forecasts 

      Fjukstad, Bård; Bjørndalen, John Markus; Anshus, Otto (Chapter; Bokkapittel, 2014-01)
      The Collaborative Symbiotic Weather Forecasting system, CSWF, let individual users do on-demand small region, short-term, and very high-resolution forecasts. When the regions have some overlap, a symbiotic forecast can be produced based on the individual forecasts from each region. Small differences in where the center of the region is located when there is complex terrain in the region, leads to ...
    • Using machine learning to provide automatic image annotation for wildlife camera traps in the Arctic 

      Thom, Håvard; Bjørndalen, John Markus; Kleiven, Eivind Flittie; Soininen, Eeva M; Killengreen, Siw Turid; Ehrich, Dorothee; Ims, Rolf Anker; Anshus, Otto; Horsch, Alexander (Chapter; Bokkapittel, 2017)
      The arctic tundra is considered the terrestrial biome expected to be most impacted by climate change, with temperatures projected to increase as much as 10 °C by the turn of the century. The Climate-ecological Observatory for Arctic Tundra (COAT) project monitors the climate and ecosystems using several sensor types. We report on results from projects that automate image annotations from two of the ...