data interval
Adaptive PCA-Based Outlier Detection for Multi-Feature Time Series in Space Missions
Ekelund, Jonah, Raptis, Savvas, Toy-Edens, Vicki, Mo, Wenli, Turner, Drew L., Cohen, Ian J., Markidis, Stefano
Analyzing multi-featured time series data is critical for space missions making efficient event detection, potentially onboard, essential for automatic analysis. However, limited onboard computational resources and data downlink constraints necessitate robust methods for identifying regions of interest in real time. This work presents an adaptive outlier detection algorithm based on the reconstruction error of Principal Component Analysis (PCA) for feature reduction, designed explicitly for space mission applications. The algorithm adapts dynamically to evolving data distributions by using Incremental PCA, enabling deployment without a predefined model for all possible conditions. A pre-scaling process normalizes each feature's magnitude while preserving relative variance within feature types. We demonstrate the algorithm's effectiveness in detecting space plasma events, such as distinct space environments, dayside and nightside transients phenomena, and transition layers through NASA's MMS mission observations. Additionally, we apply the method to NASA's THEMIS data, successfully identifying a dayside transient using onboard-available measurements.
- North America > United States > New York (0.04)
- North America > United States > Maryland > Prince George's County > Laurel (0.04)
- Europe > Sweden > Stockholm > Stockholm (0.04)
- Government > Space Agency (0.74)
- Government > Regional Government > North America Government > United States Government (0.74)
An Ensemble Scheme for Proactive Dominant Data Migration of Pervasive Tasks at the Edge
Boulougaris, Georgios, Kolomvatsos, Kostas
Nowadays, a significant focus within the research community on the intelligent management of data at the confluence of the Internet of Things (IoT) and Edge Computing (EC) is observed. In this manuscript, we propose a scheme to be implemented by autonomous edge nodes concerning their identifications of the appropriate data to be migrated to particular locations within the infrastructure, thereby facilitating the effective processing of requests. Our objective is to equip nodes with the capability to comprehend the access patterns relating to offloaded data-driven tasks and to predict which data ought to be returned to the original nodes associated with those tasks. It is evident that these tasks depend on the processing of data that is absent from the original hosting nodes, thereby underscoring the essential data assets that necessitate access. To infer these data intervals, we utilize an ensemble approach that integrates a statistically oriented model and a machine learning framework. As a result, we are able to identify the dominant data assets in addition to detecting the density of the requests. A detailed analysis of the suggested method is provided by presenting the related formulations, which is also assessed and compared with models found in the relevant literature.
- North America > United States > California > Santa Clara County > San Jose (0.04)
- Europe > North Macedonia (0.04)
- Europe > Italy > Lazio > Rome (0.04)
- (3 more...)
A Gentle Introduction and Survey on Computing with Words (CWW) Methodologies
Gupta, Prashant K., Andreu-Perez, Javier
Human beings have an inherent capability to use linguistic information (LI) seamlessly even though it is vague and imprecise. Computing with Words (CWW) was proposed to impart computing systems with this capability of human beings. The interest in the field of CWW is evident from a number of publications on various CWW methodologies. These methodologies use different ways to model the semantics of the LI. However, to the best of our knowledge, the literature on these methodologies is mostly scattered and does not give an interested researcher a comprehensive but gentle guide about the notion and utility of these methodologies. Hence, to introduce the foundations and state-of-the-art CWW methodologies, we provide a concise but a wide-ranging coverage of them in a simple and easy to understand manner. We feel that the simplicity with which we give a high-quality review and introduction to the CWW methodologies is very useful for investigators, especially those embarking on the use of CWW for the first time. We also provide future research directions to build upon for the interested and motivated researchers.
- North America > United States (0.15)
- Europe > United Kingdom > England > Essex > Colchester (0.04)
- Europe > Spain > Andalusia > Jaén Province > Jaén (0.04)
- Europe > Germany > Saarland > Saarbrücken (0.04)
- Workflow (0.97)
- Research Report (0.82)