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Big data analytics for time critical maritime and aerial mobility forecasting
The correlated exploitation of heterogeneous data sources offering very large archival and streaming data is important to increase the accuracy of computations when analysing and predicting future states of moving entities. Aiming to significantly advance the capacities of systems to improve safety and effectiveness of critical operations involving a large number of moving entities in large geographical areas, this paper describes progress achieved towards time critical big data analytics solutions to user-defined challenges in the air-traffic management and maritime domains. Besides, this paper presents further research challenges concerning data integration and management, predictive analytics for trajectory and events forecasting, and visual analytics
Fundamental Elements of Drone Management Systems in Air Traffic Planning
Drones or Unmanned Aerial Systems (UAV – Unmanned Aerial Vehicles or UAS – UnmannedAerial Systems) are vehicles that can fly without the need for a pilot or passengers. Drones can be controlled remotely through radio waves or independently (with a previously determined route). The amount of documented accidents involving the hazardous use of drones has risensignificantly due to the increased usage of drones. To perform and increase the use of drones in air traffic management (ATM), especially in smart city planning, a variety of regulations andmanagement procedures will be implemented. This paper aims to propose management rules or regulations for drones in smart city transportation management and some approaches related to drone management and drone control. To present controlling approaches through the parameters in mathematical modelling for drones, we need a control rule, data gathering from the surroundings (usage of GIS), and a dynamic model of drones, and to present controlling and managing it with the help of a drone-following model based on a dynamic model of drones
Joint University Program for Air Transportation Research, 1986
The research conducted under the NASA/FAA sponsored Joint University Program for Air Transportation Research is summarized. The Joint University Program is a coordinated set of three grants sponsored by NASA and the FAA, one each with the Mass. Inst. of Tech., Ohio Univ., and Princeton Univ. Completed works, status reports, and bibliographies are presented for research topics, which include computer science, guidance and control theory and practice, aircraft performance, flight dynamics, and applied experimental psychology. An overview of activities is presented
Computational Algorithm for Dynamic Hybrid Bayesian Network in On-line System Health Management Applications
With the increasing complexity of today's engineering systems that contain various component dependencies and degradation behaviors, there has been increasing interest in on-line System Health Management (SHM) capability to continuously monitor (via sensors and other methods of observation) system software, and hardware components for detection and diagnostic of safety-critical systems. Bayesian Network (BN) and their extension for time-series modeling known as Dynamic Bayesian Network (DBN) have been shown by recent studies to be capable of providing a unified framework for system health diagnosis and prognosis. BN has many modeling features, such as multi-state variables, noisy gates, dependent failures, and general posterior analysis. BN also allows a compact representation of the temporal and functional dependencies among system components. However, one of the barriers to applying BN in real-world problems is limitation in adequately handle "hybrid models", which contain both discrete and continuous variables, with both static and time-dependent failure distributions.
This research presents a new modeling approach, computational algorithm, and an example application for health monitoring and learning in on-line SHM. A hybrid DBN is introduced to represent complex engineering systems with underlying physics of failure by modeling a theoretical or empirical degradation model with continuous variables. The methodology is designed to be flexible and intuitive, and scalable from small, localized functionality to large complex dynamic systems. Markov Chain Monte Carlo (MCMC) inference is optimized using a pre-computation strategy and dynamic programming for on-line monitoring of system health. Proposed Monitoring and Anomaly Detection algorithm uses pattern recognition to improve failure detection and estimation of Remaining Useful Life (RUL). Pre-computation inference database enables efficient on-line learning and maintenance decision-making. The scope of this research includes a new modeling approach, computation algorithm, and an example application for on-line SHM
Bayesian Network Analysis for Diagnostics and Prognostics of Engineering Systems
Bayesian networks have been applied to many different domains to perform prognostics, reduce risk and ultimately improve decision making. However, these methods have not been applied to military field and human performance data sets in an industrial environment. Methods frequently rely on a clear understanding of causal connections leading to an undesirable event and detailed understanding of the system behavior. Methods may also require large amount of analyst teams and domain experts, coupled with manual data cleansing and classification. The research performed utilized machine learning algorithms (such as Bayesian networks) and two existing data sets. The primary objective of the research was to develop a diagnostic and prognostic tool utilizing Bayesian networks that does not require the need for detailed causal understanding of the underlying system. The research yielded a predictive method with substantial benefits over reactive methods. The research indicated Bayesian networks can be trained and utilized to predict failure of several important components to include potential malfunction codes and downtime on a real-world Navy data set. The research also considered potential error within the training data set. The results provided credence to utilization of Bayesian networks in real field data – which will always contain error that is not easily quantified. Research should be replicated with additional field data sets from other aircraft. Future research should be conducted to solicit and incorporate domain expertise into subsequent models. Research should also consider incorporation of text based analytics for text fields, which was considered out of scope for this research project
Human-in-the-Loop Methods for Data-Driven and Reinforcement Learning Systems
Recent successes combine reinforcement learning algorithms and deep neural
networks, despite reinforcement learning not being widely applied to robotics
and real world scenarios. This can be attributed to the fact that current
state-of-the-art, end-to-end reinforcement learning approaches still require
thousands or millions of data samples to converge to a satisfactory policy and
are subject to catastrophic failures during training. Conversely, in real world
scenarios and after just a few data samples, humans are able to either provide
demonstrations of the task, intervene to prevent catastrophic actions, or
simply evaluate if the policy is performing correctly. This research
investigates how to integrate these human interaction modalities to the
reinforcement learning loop, increasing sample efficiency and enabling
real-time reinforcement learning in robotics and real world scenarios. This
novel theoretical foundation is called Cycle-of-Learning, a reference to how
different human interaction modalities, namely, task demonstration,
intervention, and evaluation, are cycled and combined to reinforcement learning
algorithms. Results presented in this work show that the reward signal that is
learned based upon human interaction accelerates the rate of learning of
reinforcement learning algorithms and that learning from a combination of human
demonstrations and interventions is faster and more sample efficient when
compared to traditional supervised learning algorithms. Finally,
Cycle-of-Learning develops an effective transition between policies learned
using human demonstrations and interventions to reinforcement learning. The
theoretical foundation developed by this research opens new research paths to
human-agent teaming scenarios where autonomous agents are able to learn from
human teammates and adapt to mission performance metrics in real-time and in
real world scenarios.Comment: PhD thesis, Aerospace Engineering, Texas A&M (2020). For more
information, see https://vggoecks.com
Architectures for embedded multimodal sensor data fusion systems in the robotics : and airport traffic suveillance ; domain
Smaller autonomous robots and embedded sensor data fusion systems often suffer from limited
computational and hardware resources. Many ‘Real Time’ algorithms for multi modal sensor data
fusion cannot be executed on such systems, at least not in real time and sometimes not at all, because
of the computational and energy resources needed, resulting from the architecture of the
computational hardware used in these systems. Alternative hardware architectures for generic
tracking algorithms could provide a solution to overcome some of these limitations. For tracking and
self localization sequential Bayesian filters, in particular particle filters, have been shown to be able to
handle a range of tracking problems that could not be solved with other algorithms. But particle filters
have some serious disadvantages when executed on serial computational architectures used in most
systems. The potential increase in performance for particle filters is huge as many of the computational
steps can be done concurrently. A generic hardware solution for particle filters can relieve the central
processing unit from the computational load associated with the tracking task.
The general topic of this research are hardware-software architectures for multi modal sensor data
fusion in embedded systems in particular tracking, with the goal to develop a high performance
computational architecture for embedded applications in robotics and airport traffic surveillance
domain. The primary concern of the research is therefore: The integration of domain specific concept
support into hardware architectures for low level multi modal sensor data fusion, in particular
embedded systems for tracking with Bayesian filters; and a distributed hardware-software tracking
systems for airport traffic surveillance and control systems.
Runway Incursions are occurrences at an aerodrome involving the incorrect presence of an aircraft,
vehicle, or person on the protected area of a surface designated for the landing and take-off of aircraft.
The growing traffic volume kept runway incursions on the NTSB’s ‘Most Wanted’ list for safety
improvements for over a decade. Recent incidents show that problem is still existent. Technological
responses that have been deployed in significant numbers are ASDE-X and A-SMGCS. Although these
technical responses are a significant improvement and reduce the frequency of runway incursions,
some runway incursion scenarios are not optimally covered by these systems, detection of runway
incursion events is not as fast as desired, and they are too expensive for all but the biggest airports.
Local, short range sensors could be a solution to provide the necessary affordable surveillance accuracy
for runway incursion prevention. In this context the following objectives shall be reached. 1) Show the
feasibility of runway incursion prevention systems based on localized surveillance. 2) Develop a design
for a local runway incursion alerting system. 3) Realize a prototype of the system design using the
developed tracking hardware.Kleinere autonome Roboter und eingebettete Sensordatenfusionssysteme haben oft mit stark
begrenzter Rechenkapazität und eingeschränkten Hardwareressourcen zu kämpfen. Viele
Echtzeitalgorithmen für die Fusion von multimodalen Sensordaten können, bedingt durch den hohen
Bedarf an Rechenkapazität und Energie, auf solchen Systemen überhaupt nicht ausgeführt werden,
oder zu mindesten nicht in Echtzeit. Der hohe Bedarf an Energie und Rechenkapazität hat seine
Ursache darin, dass die Architektur der ausführenden Hardware und der ausgeführte Algorithmus
nicht aufeinander abgestimmt sind. Dies betrifft auch Algorithmen zu Spurverfolgung. Mit Hilfe von
alternativen Hardwarearchitekturen für die generische Ausführung solcher Algorithmen könnten sich
einige der typischerweise vorliegenden Einschränkungen überwinden lassen. Eine Reihe von Aufgaben,
die sich mit anderen Spurverfolgungsalgorithmen nicht lösen lassen, lassen sich mit dem Teilchenfilter,
einem Algorithmus aus der Familie der Bayesschen Filter lösen. Bei der Ausführung auf traditionellen
Architekturen haben Teilchenfilter gegenüber anderen Algorithmen einen signifikanten Nachteil,
allerdings ist hier ein großer Leistungszuwachs durch die nebenläufige Ausführung vieler
Rechenschritte möglich. Eine generische Hardwarearchitektur für Teilchenfilter könnte deshalb die
oben genannten Systeme stark entlasten.
Das allgemeine Thema dieses Forschungsvorhabens sind Hardware-Software-Architekturen für die
multimodale Sensordatenfusion auf eingebetteten Systemen - speziell für Aufgaben der
Spurverfolgung, mit dem Ziel eine leistungsfähige Architektur für die Berechnung entsprechender
Algorithmen auf eingebetteten Systemen zu entwickeln, die für Anwendungen in der Robotik und
Verkehrsüberwachung auf Flughäfen geeignet ist. Das Augenmerk des Forschungsvorhabens liegt
dabei auf der Integration von vom Einsatzgebiet abhängigen Konzepten in die Architektur von
Systemen zur Spurverfolgung mit Bayeschen Filtern, sowie auf verteilten Hardware-Software
Spurverfolgungssystemen zur Überwachung und Führung des Rollverkehrs auf Flughäfen.
Eine „Runway Incursion“ (RI) ist ein Vorfall auf einem Flugplatz, bei dem ein Fahrzeug oder eine Person
sich unerlaubt in einem Abschnitt der Start- bzw. Landebahn befindet, der einem Verkehrsteilnehmer
zur Benutzung zugewiesen wurde. Der wachsende Flugverkehr hat dafür gesorgt, das RIs seit über
einem Jahrzehnt auf der „Most Wanted“-Liste des NTSB für Verbesserungen der Sicherheit stehen.
Jüngere Vorfälle zeigen, dass das Problem noch nicht behoben ist. Technologische Maßnahmen die in
nennenswerter Zahl eingesetzt wurden sind das ASDE-X und das A-SMGCS. Obwohl diese Maßnahmen
eine deutliche Verbesserung darstellen und die Zahl der RIs deutlich reduzieren, gibt es einige RISituationen
die von diesen Systemen nicht optimal abgedeckt werden. Außerdem detektieren sie RIs
ist nicht so schnell wie erwünscht und sind - außer für die größten Flughäfen - zu teuer. Lokale Sensoren
mit kurzer Reichweite könnten eine Lösung sein um die für die zuverlässige Erkennung von RIs
notwendige Präzision bei der Überwachung des Rollverkehrs zu erreichen. Vor diesem Hintergrund
sollen die folgenden Ziele erreicht werden. 1) Die Machbarkeit eines Runway Incursion
Vermeidungssystems, das auf lokalen Sensoren basiert, zeigen. 2) Einen umsetzbaren Entwurf für ein
solches System entwickeln. 3) Einen Prototypen des Systems realisieren, das die oben gennannte
Hardware zur Spurverfolgung einsetzt
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