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Research About the Efficient Recording Structure of Installed Data Recording DevicesLee, Hyun-Kyu, Lee, Hyun-So, Song, Jae-Hoon 10 1900 (has links)
ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / Although the wireless data transmission technologies have evolved significantly, data recording devices are still being used because of the limitations of data rates and reliability issues over wireless environment in the avionics, military, space etc. Payload has limitation of weight. In addition, storage has limitation of capacity. So, we need to research about a data recording structure within a limited amount of memory. In this paper, we propose a new data recording structure through a condition necessary for efficient use of memory. The proposed structure has an equivalent function as other recording systems. But, it uses less memory than the other equivalent recording structures.
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Optimisation du système de surveillance des hélicoptères pour l'amélioration du diagnostic et de la maintenanceWiig, Johan 11 December 2006 (has links) (PDF)
Le système de surveillance (HUMS) installé dans les hélicoptères permet d'anticiper les anomalies et de donner la possibilité d'effectuer des tâches de maintenance prédictive avant l'apparition de défauts critiques. Par ailleurs, HUMS est également destiné à détecter la propagation de défauts émergents. Ceci consiste à comparer les caractéristiques vibratoires en vol de l'hélicoptère aux caractéristiques d'un état normal prédéfini. L'inconvénient majeur de cette approche est que les caractéristiques de l'état normal sont relatives au type de l'hélicoptère et changent après les tâches de révision et de maintenance, ce qui nécessite un réapprentissage de ces caractéristiques. Cette étude présente des méthodes d'évaluation de la progression temporelle des signatures vibratoires. L'étude de l'évolution de la signature vibratoire dans le temps permet de détecter des événements comme des interventions de maintenance ou des propagations de défauts sans avoir à définir un modèle de l'état de bon fonctionnement de l'appareil. Des méthodes fondées sur des modèles paramétriques et des bancs de filtres d'analyse vibratoire ont été testées et validées. Finalement, une méthode de détection de défauts a été mise en oeuvre et a donné de meilleurs résultats que les méthodes traditionnelles utilisées.
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An overview of Product Service System through Integrated Vehicle Health Management in an information sensitive industryEhlin, Max January 2019 (has links)
Purpose – The research purpose is to enhance knowledge of how organizations can form a PSS through an IVHM system when information is sensitive. Method – A single case study design of abductive approach was used, with data collection through six semi-structured interviews. Findings – A system combining IVHM and PSS has many potential benefits, however there are several challenges that need to be overcome in order to implementing a successful model. Theoretical implications – This study treads a new area not previously explored in the literature when it combines PSS and IVHM, which relies heavily on information flow to succeed, with a case of information sensitivity. This study hence explores a problematic area for either PSS or IVHM, expanding the current literature and providing initial suggestions of how to navigate this. Practical implications – Firstly, it shows managers the challenges that comes with implementing PSS-IVHM and increasing involvement in the customers’ processes. Secondly, this study shows the theoretical and general challenges of PSS-IVHM and applies the case study’s perspective of information management, granting managers a larger foundation of knowledge before starting their initiatives of PSS-IVHM. Limitations and future research – This study provides a limited amount of empirical data. Therefore, future research should focus on increasing and widening data collection. The study suggests there is a considerable challenge in conservatism within the defence industry and therefore future research is suggested to explore how change management can combat this challenge.
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Structural FRF Measurements up to 50 kHz to Assist Frequency Band Selection for Machinery Health MonitoringLarsen, Christopher G. 20 September 2012 (has links)
No description available.
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LONG TERM VEHICLE HEALTH MONITORINGCridland, Doug, Dehmelt, Chris 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / While any vehicle that is typically part of a flight test campaign is heavily instrumented to validate its performance, long term vehicle health monitoring is performed by a significantly reduced number of sensors due to a number of issues including cost, weight and maintainability. The development and deployment of smart sensor buses has reached a time in which they can be integrated into a larger data acquisition system environment. The benefits of these types of buses include a significant reduction in the amount of wiring and overall system complexity by placing the appropriate signal conditioners close to their respective sensors and providing data back over a common bus, that also provides a single power source. The use of a smart-sensor data collection bus, such as IntelliBus™1 or IEEE-1451, along with the continued miniaturization of signal conditioning devices, leads to the interesting possibility of permanently embedding data collection capabilities within a vehicle after the initial flight test effort has completed, providing long-term health-monitoring and diagnostic functionality that is not available today. This paper will discuss the system considerations and the benefits of a smart sensor based system and how pieces can be transitioned from flight qualification to long-term vehicle health monitoring in production vehicles.
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An analysis of the integrated mechanical diagnostics health and usage management system on rotor track and balanceRevor, Mark S. 06 1900 (has links)
Approved for public release, distribution is unlimited / This thesis is concerned with the operational benefit of the Integrated Mechanical Diagnostics Health and Usage Management Systems (IMD HUMS) rotor track and balance (RTB) functionality. The questions addressed are whether there is a savings in flight hours expended on functional check flights (FCF's) when compared to present practices, if there will there be a reduction in directed maintenance man-hours (DMMH) spent on maintenance related to the rotor system, and the impact on Operational Availability. Experiments were conducted using a discrete event simulation model of squadron flight operations and organizational level maintenance. The simulation is generic and can be used in the analysis of other helicopters. Input parameters governing the distributions of maintenance action inter-arrival times were estimated from Naval Aviation Logistics Data Analysis (NALDA) databases and squadron experiences on such systems. The analysis suggests that flight hours spent in FCF are dependent upon vibration growth rate, an unknown quantity, and the maintenance policy for rotor smoothing. Directed maintenance man-hours decrease with increasing numbers of IMD HUMS configured aircraft and further gains are achieved with a maintenance policy suited to a continuous monitoring system. / Captain, United States Marine Corps
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Smart offshore structure for reliability prediction processNwankwo, Cosmas Chidozie 09 1900 (has links)
A review of the developments within the field of structural reliability theory shows that
some gaps still exist in the reliability prediction process and hence there is an urgent
desire for improvements such that the estimated structural reliability will be capable of
expressing a physical property of the given structure. The current reliability prediction
process involves the continuous estimation and use of reliability index as a way of
estimating the safety of any given structure. The reliability index β depends on the
Probability Density Function (PDF) distribution for the wave force and the corresponding
PDF of resistance from respective structural members of the given structure. The PDF
for the applied wave force will depend on the PDF of water depth, wave angular velocity
and wave direction hence the reliability index as currently practiced is a statistical way
of managing uncertainties based on a general probabilistic model.
This research on Smart Offshore Structure for Reliability Prediction has proposed the
design of a measurement based reliability prediction process as a way of closing the
gap on structural reliability prediction process. Structural deflection and damping are
some of the measurable properties of an offshore structure and this study aims at
suggesting the use of these measurable properties for improvements in structural
reliability prediction process. A design case study has shown that a typical offshore
structure can deflect to a range of only a few fractions of a millimetre. This implies that if
we have a way of monitoring this level of deflection, we could use the results from such
measurement for the detection of a structural member failure. This advocated concept is
based on the hypothesis that if the original dynamic characteristics of a structure is
known, that measurement based modified dynamic properties can be used to determine
the onset of failure or failure propagation of the given structure.
This technology could reveal the location and magnitude of internal cracks or corrosion
effects on any given structure which currently is outside the current probability based
approach. A simple economic analysis shows that the recommended process shows a
positive net present value and that some $74mln is the Value of Information for any life
extension technology that could reveal the possibility of extending the life of a given
10,000bopd production platform from 2025 to 2028.
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