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Dissertation
Master thesis and internship[BR]- Master's thesis : Modeling photometric detection of space debris for a star-tracker-based space situational awareness network[BR]- Internship
Authors: --- --- ---
Year: 2024 Publisher: Liège Université de Liège (ULiège)

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This thesis contributes to the global efforts of space debris mitigation and monitoring by offering&#13;a photometric model of space debris in Earth’s orbit with the aim to integrate such a model&#13;into arcsec’s star simulator Intergalactic, aiding arcsec’s DeDUST project in the elaboration of&#13;a space situational awareness strategy based on star trackers.&#13;The model has been elaborated following a thorough review of the current literature body surrounding the photometric representation of spacecraft and their debris. After a mathematical&#13;basis has been established, an algorithm was implemented in MATLAB, with the aid of such&#13;open-source tools and NAIF’s Spice and NASA’ GMAT. The produced algorithm has been tested&#13;against both simulated cases and real photometric measures in order to both validate the model&#13;and find an optimal arrangement of its numerical parameters. The produced optimal model has&#13;been used to analyze the possible applications for optics-based space debris detection.&#13;It was found that a brightness model with a 26.5% specular component allows to most closely&#13;estimate the visual magnitude of several bodies of varying nature and size. The model’s limitation&#13;has been identified with respect to an object’s size-to-distance from the sensor (d to R)&#13;ratio. Indeed, when (d/R)^2 ≤ 1.5 × 10^−13, the model provides a visual magnitude estimation with&#13;a maximum of 10% error, and a maximum of 20% error for 1.5 × 10^−13 ≤ (d/R)^2 ≤ 1.5 × 10^−12.&#13;An inspection of the model’s response has confirmed the DeDUST project’s aim to detect debris&#13;down to 3 centimeters in size to be a perfectly realizable task. In fact, it was found that a debris&#13;detecting system based on arcsec’s Sagitta star tracker is bound to have an operating range of at&#13;least 10 kilometers for small untracked debris of 3 to 10 centimeters in size. It was also confirmed&#13;that the debris is most likely to appear as streaks to a star tracker rather than a singular and&#13;well-defined object.&#13;Ultimately, this thesis proves as an enlightening tool in the elaboration of space-debris detection&#13;strategies as well as completes the existing body of literature by focusing on the intricacies of&#13;space debris photometry.


Periodical
... IEEE International Inter-Disciplinary Conference on Cognitive Methods in Situation Awareness and Decision Support.


Book
Cyber-physical events emulation based transmission and distribution co-simulation for situation awareness and grid anomaly (SAGA) detection : preprint
Authors: --- --- ---
Year: 2021 Publisher: Golden, CO : National Renewable Energy Laboratory,

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Book
Speed and the fog of war : sense and respond logistics in Operation Iraqi Freedom-I
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Year: 2009 Publisher: [Washington, D.C.] : Center for Technology and National Security Policy,

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Book
Situational awareness for electric utilities
Authors: ---
Year: 2019 Publisher: Gaithersburg, MD : National Institute of Standards and Technology, U.S. Department of Commerce, National Cybersecurity Center of Excellence,

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Dissertation
Mémoire, y compris stage professionnalisant[BR]- Séminaires méthodologiques intégratifs[BR]- Mémoire : L'utilisation du programme TeamSTEPPS améliore-t-elle le niveau de conscience situationnelle lors d une situation aiguë, au sein d une équipe médico-infirmière ?
Authors: --- --- --- --- --- et al.
Year: 2024 Publisher: Liège Université de Liège (ULiège)

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Introduction : La qualité des soins et la sécurité du patient ont été décrites comme des enjeux majeurs dans le monde de la santé. Les compétences non techniques sont régulièrement identifiées comme faisant défaut lors de la retranscription des faits qui ont mené à des évènements indésirables liés aux soins. Dans cet ensemble, c’est la conscience situationnelle qui a été sélectionnée comme sujet principal de l’étude. Après une revue de la littérature, l’échelle SAGAT est admise comme le gold standard pour l’évaluation de cette capacité. Parmi les différentes solutions mises en évidence, le TeamSTEPPS est un programme développé dans le but d’optimiser les facteurs non techniques. L’objectif de l’étude est donc d’améliorer la conscience situationnelle, sous le postulat que cela améliorera la performance des soignants lorsqu’ils font face à une situation aigue.&#13;Matériel et méthodes : 30 individus travaillant dans le service des soins intensifs sur le site de Mont-Godinne du CHU UCL Namur sont sélectionnés. Ils constituent 10 groupes, composés chacun d’un médecin et de 2 infirmiers. La moitié des équipes subissent l’intervention, une mini-session de cours issu du programme TeamSTEPPS, sur le module spécifique de monitorage de la situation. Les 5 autres groupes ne reçoivent quant à eux pas d’intervention. La conscience situationnelle de chaque individu est évaluée grâce à des échelles SAGAT. Celles-ci sont administrées lors de séances de simulation avant et après l’intervention. Les scores sont ensuite analysés et comparés sur le plan statistique.&#13;Résultats : Les équipes qui ont suivi la mini session de cours augmentent leurs niveaux de conscience situationnelle en moyenne de 5%, en comparaison aux groupes n’ayant pas subi l’intervention. Les valeurs ne sont toutefois pas statistiquement significatives (P = 0,2). Les modèles de régression linéaires dévoilent des résultats similaires (simple, beta = 6,3%, P = 0,2 ; multiple, beta = 8,4%, P = 0,3).&#13;Conclusion : Le TeamSTEPPS semble améliorer le niveau de conscience situationnelle des individus ayant suivi le programme. Toutefois, les valeurs décelées ne permettent pas d’affirmer de certitudes sur le plan statistique, et donc scientifique. Des études supplémentaires, multicentriques et avec des échantillons plus importants sont nécessaires. Introduction : Quality of care and patient safety have been described as major issues in the healthcare world. Non-technical skills are regularly identified as lacking in the transcription of events leading to adverse events in healthcare. In this context, situational awareness was selected as the main focus of the study. After a review of the literature, the SAGAT scale was accepted as the gold standard for assessing this ability. Among the various solutions identified, TeamSTEPPS is a program developed to optimize non-technical factors. The aim of the study is therefore to improve situational awareness, on the assumption that this will improve caregivers' performance when faced with an acute situation.&#13;Materials and methods : 30 individuals working in the intensive care unit at the Mont-Godinne site of CHU UCL Namur were selected. They form 10 groups, each comprising a doctor and 2 nurses. Half of the teams undergo the intervention, a mini-course from the TeamSTEPPS program, on the specific situation monitoring module. The other 5 groups receive no intervention. Each individual's situational awareness is assessed using SAGAT scales. These are administered during simulation sessions before and after the intervention. Scores are then analyzed and statistically compared.&#13;Results : Teams who attended the mini-course increased their levels of situational awareness by an average of 5%, compared with groups who did not undergo the intervention. However, the values were not statistically significant (P = 0.2). Linear regression models revealed similar results (simple, beta = 6.3%, P = 0.2; multiple, beta = 8.4%, P = 0.3).&#13;Conclusion : TeamSTEPPS appears to improve the level of situational awareness of individuals who have completed the program. However, the values detected do not allow us to assert statistical, and therefore scientific, certainties. Further multi-center studies with larger sample sizes are required.


Book
Providing orbit information with predetermined bounded accuracy
Author:
ISBN: 9783832544058 Year: 2016 Publisher: Berlin/Germany Logos Verlag Berlin

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The exchange of orbit information is becoming more important in view of the increasing population of objects in space as well as the increase in parties involved in space operations. The aim of this thesis was to investigate how orbit information maintained by a space surveillance system can be provided to its users. Services like collision avoidance require very accurate information, while other services might be less stringent. An approach was studied, which allows to derive orbit and covariance information of predetermined accuracy from a reference orbit. Using Chebyshev polynomials, continuous state vector and covariance matrix information can be provided. The major advantage is that no inter- or extrapolation on the user's side is required. A method to reduce the data amount by interpolating the variance envelope functions was also studied. The proposed method in this thesis gives access to highly accurate information from the catalogue, where this information is required. On the other hand it can also provide less accurate information, where requirements are less restrictive, thereby allowing for a significantly reduced amount of data to be transferred and stored.


Book
Distributed situation awareness
Author:
ISBN: 0754670589 9786612344343 128234434X 0754696820 1317149378 1315577658 9780754696827 1317149386 9780754670582 9781282344341 6612344342 9780754670582 9781317149385 9781315577654 9781317149378 Year: 2009 Publisher: Farnham, England Burlington, VT Ashgate

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"Having an accurate understanding of what is going on is a key commodity for teams working within military systems. 'Situation awareness' (SA) is the term that is used within human factors circles to describe the level of awareness that operators have of the situation that they are engaged in; it focuses on how operators develop and maintain a sufficient understanding of 'what is going on' in order to achieve success in task performance. Over the past two decades, the construct has become a fundamental theme within the areas of system design and evaluation and has received considerable attention from the human factors research community. Despite this, there is still considerable debate over how SA operates in complex collaborative systems and how SA achievement and maintenance is best supported through system, procedure and interface design. This book focuses on the recently developed concept of distributed situation awareness, which takes a systems perspective on the concept and moves the focus on situation awareness out of the heads of individual operators and on to the overall joint cognitive system consisting of human and technological agents. Situation awareness is viewed as an emergent property of collaborative systems, something that resides in the interaction between elements of the system and not in the heads of individual operators working in that system. The first part of the book presents a comprehensive review and critique of existing SA theory and measurement approaches, following which a novel model for complex collaborative systems, the distributed SA model, and a new modelling procedure, the propositional network approach, are outlined and demonstrated. The next part focuses on real-world applications of the model and modelling procedure, and presents four case studies undertaken in the land warfare, multinational warfare and energy distribution domains. Each case study is described in terms of the domain in question, the methodology employed, and the findings derived in relation to situation awareness theory. The third and final part of the book then concentrates on theoretical development, and uses the academic literature and the findings from the case study applications to validate and extend the distributed SA model described at the beginning of the book. In closing, the utility of the distributed SA model and modeling procedure are outlined and a series of initial guidelines for supporting distributed SA through system design are articulated."--Provided by publisher.

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