Littérature scientifique sur le sujet « Moving debris detection »
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Articles de revues sur le sujet "Moving debris detection"
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Yang, Xiaoqi, Kai Huo, Xinyu Zhang, Weidong Jiang et Yong Chen. « A Clutter-Analysis-Based STAP for Moving FOD Detection on Runways ». Sensors 19, no 3 (29 janvier 2019) : 549. http://dx.doi.org/10.3390/s19030549.
Texte intégralRésumé :
Security risks and economic losses of civil aviation caused by Foreign Object Debris (FOD) have increased rapidly. Synthetic Aperture Radars (SARs) with high resolutions potentially have the capability to detect FODs on the runways, but the target echo is hard to be distinguished from strong clutter. This paper proposes a clutter-analysis-based Space-time Adaptive Processing (STAP) method in order to obtain effective clutter suppression and moving FOD indication, under inhomogeneous clutter background. Specifically, we first divide the radar coverage into equal scattering cells in the rectangular coordinates system rather than the polar ones. We then measure normalized RCSs within the X-band and employ the acquired results to modify the parameters of traditional models. Finally, we describe the clutter expressions as responses of the scattering cells in space and time domain to obtain the theoretical clutter covariance. Experimental results at 10 GHz show that FODs with a reflection higher than −30 dBsm can be effectively detected by a Linear Constraint Minimum Variance (LCMV) filter in azimuth when the noise is −60 dBm. It is also validated to indicate a −40 dBsm target in Doppler. Our approach can obtain effective clutter suppression 60dB deeper than the training-sample-coupled STAP under the same conditions.
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Bossi, G., M. Cavalli, S. Crema, S. Frigerio, B. Quan Luna, M. Mantovani, G. Marcato, L. Schenato et A. Pasuto. « Multi temporal LiDAR-DTMs as a tool for modelling a complex landslide : a case study in the Rotolon catchment (Eastern Italian Alps) ». Natural Hazards and Earth System Sciences Discussions 2, no 10 (10 octobre 2014) : 6453–74. http://dx.doi.org/10.5194/nhessd-2-6453-2014.
Texte intégralRésumé :
Abstract. The geomorphological change detection through the comparison of repeated topographic surveys is a recent approach that benefits greatly from the latest developments in topographical data acquisition techniques. Among them, airborne LiDAR makes the monitoring of geomorphological changes a more reliable and accurate approach for natural hazard and risk management. In this study, two LiDAR-DTMs (2 m resolution) were acquired just before and after a complex 340 000 m3 landslide event (4 November 2010) that generated a debris flow in the channel of the Rotolon catchment (Eastern Italian Alps). The analysis of these data was used to set up the initial condition for the application of a dynamic model. The comparison between the pre- and post-event DTMs allowed to identify erosion and depositional areas and the volume of the landslide. The knowledge of the phenomenon dynamics was the base of a sound back-analysis of the event with the 3-D numerical model DAN3D. This particular code was selected for its capability to modify the rheology and the parameters of the moving mass during run-out, as actually observed along the path of the 2010 debris flow. Nowadays some portions of Mt. Rotolon flank are still moving and show signs of detachment. The same soil parameters used in the back-analysis model could be used to simulate the run-out for possible future landslides allowing to generate reliable risk scenarios useful for awareness of civil defense and strategy on emergency plans.
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Bossi, G., M. Cavalli, S. Crema, S. Frigerio, B. Quan Luna, M. Mantovani, G. Marcato, L. Schenato et A. Pasuto. « Multi-temporal LiDAR-DTMs as a tool for modelling a complex landslide : a case study in the Rotolon catchment (eastern Italian Alps) ». Natural Hazards and Earth System Sciences 15, no 4 (1 avril 2015) : 715–22. http://dx.doi.org/10.5194/nhess-15-715-2015.
Texte intégralRésumé :
Abstract. The geomorphological change detection through the comparison of repeated topographic surveys is a recent approach that benefits greatly from the latest developments in topographical data acquisition techniques. Among them, airborne LiDAR makes the monitoring of geomorphological changes a more reliable and accurate approach for natural hazard and risk management. In this study, two LiDAR digital terrain models (DTMs) (2 m resolution) were acquired just before and after a complex 340 000 m3 landslide event (4 November 2010) that generated a debris flow in the channel of the Rotolon catchment (eastern Italian Alps). The analysis of these data was used to set up the initial condition for the application of a dynamic model. The comparison between the pre- and post-event DTMs allowed us to identify erosion and depositional areas and the volume of the landslide. The knowledge of the phenomenon dynamics was the base of a sound back analysis of the event with the 3-D numerical model DAN3D. This particular code was selected for its capability to modify the rheology and the parameters of the moving mass during run-out, as actually observed along the path of the 2010 debris flow. Nowadays some portions of Mt. Rotolon flank are still moving and show signs of detachment. The same soil parameters used in the back-analysis model could be used to simulate the run-out for possible future landslides, allowing us to generate reliable risk scenarios useful for awareness of civil defense and strategy of emergency plans.
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Sissa, E., J. Olofsson, A. Vigan, J. C. Augereau, V. D’Orazi, S. Desidera, R. Gratton et al. « New disk discovered with VLT/SPHERE around the M star GSC 07396−00759 ». Astronomy & ; Astrophysics 613 (mai 2018) : L6. http://dx.doi.org/10.1051/0004-6361/201832740.
Texte intégralRésumé :
Debris disks are usually detected through the infrared excess over the photospheric level of their host star. The most favorable stars for disk detection are those with spectral types between A and K, while the statistics for debris disks detected around low-mass M-type stars is very low, either because they are rare or because they are more difficult to detect. Terrestrial planets, on the other hand, may be common around M-type stars. Here, we report on the discovery of an extended (likely) debris disk around the M-dwarf GSC 07396−00759. The star is a wide companion of the close accreting binary V4046 Sgr. The system probably is a member of the β Pictoris Moving Group. We resolve the disk in scattered light, exploiting high-contrast, high-resolution imagery with the two near-infrared subsystems of the VLT/SPHERE instrument, operating in the Y J bands and the H2H3 doublet. The disk is clearly detected up to 1.5′′ (~110 au) from the star and appears as a ring, with an inclination i ~ 83°, and a peak density position at ~70 au. The spatial extension of the disk suggests that the dust dynamics is affected by a strong stellar wind, showing similarities with the AU Mic system that has also been resolved with SPHERE. The images show faint asymmetric structures at the widest separation in the northwest side. We also set an upper limit for the presence of giant planets to 2 MJ. Finally, we note that the 2 resolved disks around M-type stars of 30 such stars observed with SPHERE are viewed close to edge-on, suggesting that a significant population of debris disks around M dwarfs could remain undetected because of an unfavorable orientation.
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Almeida, Sílvia, Marko Radeta, Tomoya Kataoka, João Canning-Clode, Miguel Pessanha Pais, Rúben Freitas et João Gama Monteiro. « Designing Unmanned Aerial Survey Monitoring Program to Assess Floating Litter Contamination ». Remote Sensing 15, no 1 (23 décembre 2022) : 84. http://dx.doi.org/10.3390/rs15010084.
Texte intégralRésumé :
Monitoring marine contamination by floating litter can be particularly challenging since debris are continuously moving over a large spatial extent pushed by currents, waves, and winds. Floating litter contamination have mostly relied on opportunistic surveys from vessels, modeling and, more recently, remote sensing with spectral analysis. This study explores how a low-cost commercial unmanned aircraft system equipped with a high-resolution RGB camera can be used as an alternative to conduct floating litter surveys in coastal waters or from vessels. The study compares different processing and analytical strategies and discusses operational constraints. Collected UAS images were analyzed using three different approaches: (i) manual counting (MC), using visual inspection and image annotation with object counts as a baseline; (ii) pixel-based detection, an automated color analysis process to assess overall contamination; and (iii) machine learning (ML), automated object detection and identification using state-of-the-art convolutional neural network (CNNs). Our findings illustrate that MC still remains the most precise method for classifying different floating objects. ML still has a heterogeneous performance in correctly identifying different classes of floating litter; however, it demonstrates promising results in detecting floating items, which can be leveraged to scale up monitoring efforts and be used in automated analysis of large sets of imagery to assess relative floating litter contamination.
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Shi, Di, Taimur Aftab, Gunnar Gidion, Fatma Sayed et Leonhard M. Reindl. « A Novel Electrically Small Ground-Penetrating Radar Patch Antenna with a Parasitic Ring for Respiration Detection ». Sensors 21, no 6 (10 mars 2021) : 1930. http://dx.doi.org/10.3390/s21061930.
Texte intégralRésumé :
An electrically small patch antenna with a low-cost high-permittivity ceramic substrate material for use in a ground-penetrating radar is proposed in this work. The antenna is based on a commercial ceramic 915 MHz patch antenna with a size of 25 × 25 × 4 mm3 and a weight of 12.9 g. The influences of the main geometric parameters on the antenna’s electromagnetic characteristics were comprehensively studied. Three bandwidth improvement techniques were sequentially applied to optimize the antenna: tuning the key geometric parameters, adding cuts on the edges, and adding parasitic radiators. The designed antenna operates at around 1.3 GHz and has more than 40 MHz continuous −3 dB bandwidth. In comparison to the original antenna, the −3 and −6 dB fractional bandwidth is improved by 1.8 times and 4 times, respectively. Two antennas of the proposed design together with a customized radar were installed on an unmanned aerial vehicle (UAV) for a quick search for survivors after earthquakes or gas explosions without exposing the rescue staff to the uncertain dangers of moving on the debris.
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Vouillamoz, Naomi, Sabrina Rothmund et Manfred Joswig. « Characterizing the complexity of microseismic signals at slow-moving clay-rich debris slides : the Super-Sauze (southeastern France) and Pechgraben (Upper Austria) case studies ». Earth Surface Dynamics 6, no 2 (27 juin 2018) : 525–50. http://dx.doi.org/10.5194/esurf-6-525-2018.
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Abstract. Soil and debris slides are prone to rapid and dramatic reactivation. Deformation within the instability is accommodated by sliding, whereby weak seismic energies are released through material deformation. Thus, passive microseismic monitoring provides information that relates to the slope dynamics. In this study, passive microseismic data acquired at Super-Sauze (southeastern France) and Pechgraben (Upper Austria) slow-moving clay-rich debris slides (“clayey landslides”) are investigated. Observations are benchmarked against previous similar case studies to provide a comprehensive and homogenized typology of microseismic signals at clayey landslides. A thorough knowledge of the various microseismic signals generated by slope deformation is crucial for the future development of automatic detection systems to be implemented in landslide early-warning systems. Detected signals range from short-duration (< 2 s) quake-like signals to a wide variety of longer-duration tremor-like radiations (> 2 s – several min). The complexity of seismic velocity structures, the low quantity and low quality of available signal onsets and non-optimal seismic network geometry severely impedes the source location procedure; thus, rendering source processes characterization challenging. Therefore, we constrain sources' locations using the prominent waveform amplitude attenuation pattern characteristic of near-source area (< about 50 m) landslide-induced microseismic events. A local magnitude scale for clayey landslides (ML−LS) is empirically calibrated using calibration shots and hammer blow data. The derived ML−LS returns daily landslide-induced microseismicity rates that positively correlate with higher average daily displacement rates. However, high temporal and spatial resolution analyses of the landslide dynamics and hydrology are required to better decipher the potential relations linking landslide-induced microseismic signals to landslide deformation.
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Setterfield, Timothy P., David W. Miller, John J. Leonard et Alvar Saenz-Otero. « Mapping and determining the center of mass of a rotating object using a moving observer ». International Journal of Robotics Research 37, no 1 (janvier 2018) : 83–103. http://dx.doi.org/10.1177/0278364917749024.
Texte intégralRésumé :
For certain applications, such as on-orbit inspection of orbital debris, defunct satellites, and natural objects, it is necessary to obtain a map of a rotating object from a moving observer, as well to estimate the object’s center of mass. This paper addresses these tasks using an observer that measures its own orientation, angular rate, and acceleration, and is equipped with a dense 3D visual sensor, such as a stereo camera or a light detection and ranging (LiDAR) sensor. The observer’s trajectory is estimated independently of the target object’s rotational motion. Pose-graph mapping is performed using visual odometry to estimate the observer’s trajectory in an arbitrary target-fixed frame. In addition to applying pose constraint factors between successive frames, loop closure is performed between temporally non-adjacent frames. A kinematic constraint on the target-fixed frame, resulting from the rigidity of the target object, is exploited to create a novel rotation kinematic factor. This factor connects a trajectory estimation factor graph with the mapping pose graph, and facilitates estimation of the target’s center of mass. Map creation is performed by transforming detected feature points into the target-fixed frame, centered at the estimated center of mass. Analysis of the algorithm’s computational performance reveals that its computational cost is negligible compared with that of the requisite image processing.
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Shi, Xiaoshi, Zuoliang Tang, Yihan Wang, Hong Xie et Lijia Xu. « HOG-SVM Impurity Detection Method for Chinese Liquor (Baijiu) Based on Adaptive GMM Fusion Frame Difference ». Foods 11, no 10 (17 mai 2022) : 1444. http://dx.doi.org/10.3390/foods11101444.
Texte intégralRésumé :
Chinese liquor (Baijiu) is one of the four major distilled spirits in the world. At present, liquor products containing impurities still exist on the market, which not only damage corporate image but also endanger consumer health. Due to the production process and packaging technologies, impurities usually appear in products of Baijiu before entering the market, such as glass debris, mosquitoes, aluminium scraps, hair, and fibres. In this paper, a novel method for detecting impurities in bottled Baijiu is proposed. Firstly, the region of interest (ROI) is cropped by analysing the histogram projection of the original image to eliminate redundant information. Secondly, to adjust the number of distributions in the Gaussian mixture model (GMM) dynamically, multiple unmatched distributions are removed and distributions with similar means are merged in the process of modelling the GMM background. Then, to adaptively change the learning rates of the front and background pixels, the learning rate of the pixel model is created by combining the frame difference results of the sequence images. Finally, a histogram of oriented gradient (HOG) features of the moving targets is extracted, and the Support Vector Machine (SVM) model is chosen to exclude bubble interference. The experimental results show that this impurity detection method for bottled Baijiu controls the missed rate by within 1% and the false detection rate by around 3% of impurities. Its speed is five times faster than manual inspection and its repeatability index is good, indicating that the overall performance of the proposed method is better than manual inspection with a lamp. This method is not only efficient and fast, but also provides practical, theoretical, and technical support for impurity detection of bottled Baijiu that has broad application prospects.
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Dabiri, Z., D. Hölbling, L. Abad, G. Prasicek, A. L. Argentin et T. T. Tsai. « AN OBJECT-BASED APPROACH FOR MONITORING THE EVOLUTION OF LANDSLIDE-DAMMED LAKES AND DETECTING TRIGGERING LANDSLIDES IN TAIWAN ». ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-3/W8 (20 août 2019) : 103–8. http://dx.doi.org/10.5194/isprs-archives-xlii-3-w8-103-2019.
Texte intégralRésumé :
<p><strong>Abstract.</strong> In August 2009, Typhoon Morakot caused a record-breaking rainfall in Taiwan. The heavy rainfall triggered thousands of landslides, in particular in the central-southern part of the island. Large landslides can block rivers and can lead to the formation of landslide-dammed lakes. Cascading hazards like floods and debris flows after landslide dam breaches pose a high risk for people and infrastructure downstream. Thus, better knowledge about landslides that significantly impact the channel system and about the resulting landslide-dammed lakes are key elements for assessing the direct and indirect hazards caused by the moving mass. The main objectives of this study are 1) to develop an object-based image analysis (OBIA) approach for semi-automated detection of landslides that caused the formation of landslide-dammed lakes and 2) to monitor the evolution of landslide-dammed lakes based on Landsat imagery. For landslide and lake mapping, primarily spectral indices and contextual information were used. By integrating morphological and hydrological parameters derived from a digital elevation model (DEM) into the OBIA framework, we automatically identified landslide-dammed lakes, and the landslides that likely caused the formation of those lakes, due to the input of large amounts of debris into the channel system. The proposed approach can be adapted to other remote sensing platforms and can be used to monitor the evolution of landslide-dammed lakes and triggering landslides at regional scale after typhoon and heavy rainstorm events within an efficient time range after suitable remote sensing data has been provided.</p>
Thèses sur le sujet "Moving debris detection"
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Panzardi, Enza. « Measurement systems for industrial plants condition monitoring ». Doctoral thesis, Università di Siena, 2019. http://hdl.handle.net/11365/1072401.
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Negli ultimi decenni, il mercato mondiale dell’energia ha dovuto far fronte ad una richiesta di produzione sempre crescente e ad un costante mutamento del settore industriale, sempre più attento all’impatto ambientale e all’innovazione tecnologica.
Oltre agli impianti per la produzione di energia da fonti rinnovabili, quelli a ciclo combinato o a cogenerazione basati su turbine a gas sono i più diffusi, in quanto garantiscono maggiore rendimento e minori emissioni, a parità di energia prodotta rispetto agli altri impianti a combustione disponibili nel settore. Inoltre, offrono una maggiore flessibilità operativa consentendo una migliore modulabilità del carico.
In questo contesto, una sempre maggiore spinta innovativa ha coinvolto gli operatori del settore nel mettere a punto nuove tecnologie di controllo e monitoraggio degli impianti per garantire una maggiore affidabilità e rimanere competitivi a lungo termine.
A tale scopo, sono diverse le tecniche che possono essere implementate per raccogliere informazioni sulle condizioni operative delle macchine, consentendo quindi un rilevamento e una manutenzione precoce dei guasti che posso avere un forte impatto sulla produttività e sulla riduzione complessiva dei costi.
Il mio lavoro di tesi si inserisce in questo contesto applicativo. L’obiettivo finale è stato quello di sviluppare delle tecniche di monitoraggio innovative e a basso costo basate sul principio di induzione elettrostatica per il rilevamento di detriti solidi, generati da guasti o malfunzionamenti, nel percorso dei gas di scarico di una turbomacchina.
In questo lavoro vengono presentati diversi sistemi innovativi di monitoraggio basati sull’utilizzo di sensori elettrostatici e amplificatori di carica, con prestazioni migliorate che possono essere impiegati anche in altre applicazioni che coinvolgono processi di combustione o in impianti industriali che impiegano tubazioni per il trasporto pneumatico.
Il sistema di rilevamento consiste in uno o più sensori elettrostatici montati all’interno del condotto di scarico della turbomacchina i quali rilevano le particelle con carica elettrostatica presenti nel flusso di gas. L’amplificatore di carica ha il compito di convertire il segnale di carica in un segnale di tensione adatto ad essere acquisito e processato da un sistema appositamente implementato.
La tecnica di misura implementata sfrutta le informazioni fornite dal modello fisico usato per descrivere il problema di misura e le caratteristiche geometriche del set-up scelto per i sensori per ricostruire la traiettoria, il livello di carica, la posizione e la velocità della particella carica rilevata.
Il sistema di misura realizzato è stato caratterizzato in un ampio intervallo di condizioni operative e studiato sia dal punto di vista teorico che sperimentale. In particolare, è stato sviluppato un sistema di misura basato su array circolari di tre sensori elettrostatici per il quale si riesce ad ottenere un errore relativo inferiore all’1% sulla stima dei parametri necessari alla ricostruzione della traiettoria, della velocità e della carica della particella in movimento rilevata.
Inoltre, dalla caratterizzazione teorica dell’accuratezza di misura del sistema emerge come quest’ultima sia indipendente dalla direzione assunta dalla particella in movimento rispetto alla disposizione dei sensori, garantendo un’accuratezza isotropica planare.
Inoltre, rimanendo nello stesso ambito applicativo, una parte di questo lavoro ha riguardato lo studio e la realizzazione di una sonda capacitiva triassiale. La particolarità del dispositivo proposto è quella di essere realizzato per essere depositato direttamente sul componente dell’impianto da monitorare e per questo definita: "on-component.
Un prototipo del sensore è stato realizzato con tecnologia serigrafica e il suo comportamento caratterizzato in frequenza, dimostrando caratteristiche comparabili alle comuni sonde triassiali ("bulk").
Chapitres de livres sur le sujet "Moving debris detection"
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Huntley, David, Peter Bobrowsky, Roger MacLeod, Drew Rotheram-Clarke, Robert Cocking, Jamel Joseph, Jessica Holmes et al. « IPL Project 202 : Landslide Monitoring Best Practices for Climate-Resilient Railway Transportation Corridors in Southwestern British Columbia, Canada ». Dans Progress in Landslide Research and Technology, Volume 1 Issue 1, 2022, 249–65. Cham : Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-16898-7_18.
Texte intégralRésumé :
AbstractThe paper outlines landslide mapping and change-detection monitoring protocols based on the successes of ICL-IPL Project 202 in southwestern British Columbia, Canada. In this region, ice sheets, glaciers, permafrost, rivers and oceans, high relief, and biogeoclimatic characteristics contribute to produce distinctive landslide assemblages. Bedrock and drift-covered slopes along the transportation corridors are prone to mass-wasting when favourable conditions exist. In high-relief mountainous areas, rapidly moving landslides include rock and debris avalanches, rock and debris falls, debris flows and torrents, and lahars. In areas with moderate to low relief, rapid to slow mass movements include rockslides and slumps, debris or earth slides and slumps, and earth flows. Slow-moving landslides include rock glaciers, rock and soil creep, solifluction, and lateral spreads in bedrock and surficial deposits. Research in the Thompson River Valley aims to gain a better understanding of how geological conditions, extreme weather events and climate change influence landslide activity along the national railway corridor. Remote sensing datasets, consolidated in a geographic information system, capture the spatial relationships between landslide distribution and specific terrain features, at-risk infrastructure, and the environmental conditions expected to correlate with landslide incidence and magnitude. Reliable real-time monitoring solutions for critical railway infrastructure (e.g., ballast, tracks, retaining walls, tunnels and bridges) able to withstand the harsh environmental conditions of Canada are highlighted. The provision of fundamental geoscience and baseline geospatial monitoring allows stakeholders to develop robust risk tolerance, remediation, and mitigation strategies to maintain the resilience and accessibility of critical transportation infrastructure, while also protecting the natural environment, community stakeholders, and the Canadian economy. We conclude by proposing a best-practice solution involving three levels of investigation to describe the form and function of the wide range of rapid and slow-moving landslides occurring across Canada, which is also applicable elsewhere.
Actes de conférences sur le sujet "Moving debris detection"
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van Wijhe, Andries, Lennert Buijs, Leszek Stachyra et Olivier Macchion. « Measurements of Low Frequency Vibration in Subsea Piping Using ROV Video Analysis ». Dans ASME 2020 39th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/omae2020-18579.
Texte intégralRésumé :
Abstract Vibrations in Subsea Production Systems are well recognized as a concern in the subsea industry. To identify the severity of the vibrations and potential accumulated fatigue damage, subsea vibrations need to be measured with great accuracy. Currently, accurate detection and subsea measurements are often performed by utilizing accelerometers, which have to be connected to the structure by ROV or a diver. ROV video analysis provides an alternative solution. Video analyses are widely utilized across different applications. With the increased quality of a HD camera on ROV, the accessibility of such measurements is an attractive substitute to other techniques. As a part of on-shore mechanical testing on a full assembled XT in St John’s Canada, a flowloop on a water injection XT was subjected to free vibrations. The vibrations were filmed using a commercial HD camera placed on a tripod. This test was done to validate data generated using video processing in which pipe vibration of an operating subsea XT was filmed using an ROV camera. A study that aimed to quantify the video processing accuracy, limitations and provide general guidance was conducted. For the onshore test filmed with a tripod the results of video analyses were compared with the measurements obtained by means of accelerometers. For the video of an operating subsea XT filmed by an ROV, the obtained vibration frequency and direction was compared with the free mechanical vibration obtained by a FEM model. The results obtained by means of the video analysis matched well with the accelerometer data. A high accuracy was reached, as vibration displacements as low as 20% of the pixel were accurately determined in the video analysis. With respect to detection frequencies, the upper cut-off frequency was around 15 Hz determined by the video framerate. The video analysis utilizing ROV videos was found to be applicable for low frequency vibration measurements, opening the opportunity for easier and more cost effective vibration detection and monitoring. The method is also reliable for subsea application in which the camera is placed on an ROV and is thus not affected by ROV movements, subsea lighting condition and moving ocean debris.
Rapports d'organisations sur le sujet "Moving debris detection"
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Huntley, D., D. Rotheram-Clarke, R. Cocking, J. Joseph et P. Bobrowsky. Current research on slow-moving landslides in the Thompson River valley, British Columbia (IMOU 5170 annual report). Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/331175.
Texte intégralRésumé :
Interdepartmental Memorandum of Understanding (IMOU) 5170 between Natural Resources Canada (NRCAN), the Geological Survey of Canada (GSC) and Transport Canada Innovation Centre (TC-IC) aims to gain new insight into slow-moving landslides, and the influence of climate change, through testing conventional and emerging monitoring technologies. IMOU 5107 focuses on strategically important sections of the national railway network in the Thompson River valley, British Columbia (BC), and the Assiniboine River valley along the borders of Manitoba (MN) and Saskatchewan (SK). Results of this research are applicable elsewhere in Canada (e.g., the urban-rural-industrial landscapes of the Okanagan Valley, BC), and around the world where slow-moving landslides and climate change are adversely affecting critical socio-economic infrastructure. Open File 8931 outlines landslide mapping and changedetection monitoring protocols based on the successes of IMOU 5170 and ICL-IPL Project 202 in BC. In this region, ice sheets, glaciers, permafrost, rivers and oceans, high relief, and biogeoclimatic characteristics contribute to produce distinctive rapid and slow-moving landslide assemblages that have the potential to impact railway infrastructure and operations. Bedrock and drift-covered slopes along the transportation corridors are prone to mass wasting when favourable conditions exist. In high-relief mountainous areas, rapidly moving landslides include rock and debris avalanches, rock and debris falls, debris flows and torrents, and lahars. In areas with moderate to low relief, rapid to slow mass movements include rockslides and slumps, debris or earth slides and slumps, and earth flows. Slow-moving landslides include rock glaciers, rock and soil creep, solifluction, and lateral spreads in bedrock and surficial deposits. Research efforts lead to a better understanding of how geological conditions, extreme weather events and climate change influence landslide activity along the national railway corridor. Combining field-based landslide investigation with multi-year geospatial and in-situ time-series monitoring leads to a more resilient railway national transportation network able to meet Canada's future socioeconomic needs, while ensuring protection of the environment and resource-based communities from landslides related to extreme weather events and climate change. InSAR only measures displacement in the east-west orientation, whereas UAV and RTK-GNSS change-detection surveys capture full displacement vectors. RTK-GNSS do not provide spatial coverage, whereas InSAR and UAV surveys do. In addition, InSAR and UAV photogrammetry cannot map underwater, whereas boat-mounted bathymetric surveys reveal information on channel morphology and riverbed composition. Remote sensing datasets, consolidated in a geographic information system, capture the spatial relationships between landslide distribution and specific terrain features, at-risk infrastructure, and the environmental conditions expected to correlate with landslide incidence and magnitude. Reliable real-time monitoring solutions for critical railway infrastructure (e.g., ballast, tracks, retaining walls, tunnels, and bridges) able to withstand the harsh environmental conditions of Canada are highlighted. The provision of fundamental geoscience and baseline geospatial monitoring allows stakeholders to develop robust risk tolerance, remediation, and mitigation strategies to maintain the resilience and accessibility of critical transportation infrastructure, while also protecting the natural environment, community stakeholders, and Canadian economy. We propose a best-practice solution involving three levels of investigation to describe the form and function of the wide range of rapid and slow-moving landslides occurring across Canada that is also applicable elsewhere. Research activities for 2022 to 2025 are presented by way of conclusion.