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Relevant bibliographies by topics / Deformation assessment

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Academic literature on the topic 'Deformation assessment'

Author: Grafiati

Published: 10 March 2023

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Journal articles on the topic "Deformation assessment"

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Zygmunt, Michał, Marcin Rajner, and Tomasz Liwosz. "Assessment of continental hydrosphere loading using GNSS measurements." Reports on Geodesy and Geoinformatics 101, no. 1 (June 1, 2016): 36–53. http://dx.doi.org/10.1515/rgg-2016-0020.

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Abstract Presented paper is dedicated to problems of deformation of the Earth's crust as a response to the surface loading caused by continental waters. The aim of this study was to specify areas particularly vulnerable to studied deformation and to compare calculated and observed displacements. Information of the continental water volume was taken from the WaterGAP Global Hydrological Model. Calculated values of the deformations were verified with the results obtained with programs SPOTL and grat. Vertical deformations were almost 10 times higher than the deformation in the horizontal plane, for which reason later part of the paper focuses on the former. In order to check agreement of the calculated and observed deformation 23 stations of International GNSS Service (IGS) were selected and divided into three groups (inland, near the shoreline and islands). Before comparison outliers and discontinuities were removed from GNSS observations. Modelled and observed signals were centred. The analysed time series of the vertical displacements showed that only for the inland stations it is possible to effectively remove displacements caused by mass transfer in the hydrosphere. For stations located in the coastal regions or islands, it is necessary to consider additional movement effects resulting from indirect ocean tidal loading or atmosphere loading.

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Otukei, J. R., P. Atolerea, A. Gidudu, and F. Martini. "Ground deformation assessment of the Albertine graben using inSAR." South African Journal of Geomatics 8, no. 2 (September 8, 2022): 130–43. http://dx.doi.org/10.4314/sajg.v8i2.2.

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Information on deformation of the land surface is vital for planning of infrastructure especially in areas such as the Albertine graben with substantial amounts of oil discoveries. Traditionally, global positioning systems, precise leveling and geotechnical techniques have been used for assessing and monitoring ground deformations. While these techniques provide accurate information, they are point based, expensive, time consuming and labour intensive over large area monitoring. This study explored an interferometric synthetic aperture radar (InSAR) approach for mapping deformation over Buliisa oil discovery area located in the Western arm of the East African rift valley. The method was implemented by measuring the phase differences of ALOS PALSAR data acquired between 2007 and 2011. Deformation estimates varied between -0.45m to +0.34m while the mean displacements varied from –0.10m to 0.089m. High ground deformation was detected in the Southern, North Eastern and North Western parts contributed by agricultural activity and drilling pad constructions. Generally, analysis of ALOS PALSAR data using InSAR approach provides a viable option for assessing land surface deformation in Buliisa oil exploration area.

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Wu, Qian, Yizhuo Hu, Ming Dong, Bo Song, Changjie Xia, Boning Yu, Zhibin Zhang, and Yang Liu. "Optimization of Transformer Winding Deformation Assessment Criterion Considering Insulation Aging and Moisture Content." Energies 13, no. 24 (December 8, 2020): 6491. http://dx.doi.org/10.3390/en13246491.

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Frequency response analysis is widely used to diagnose transformer winding deformation faults due to its high sensitivity, strong anti-interference capability, and equipment portability, but the results of frequency response analysis can be affected by insulation aging and moisture in the transformer, leading to errors in the diagnosis of winding deformation faults. Currently, there is no effective method to prevent such errors. This paper focuses on optimizing the criterion for diagnosing winding deformations when insulation aging and moisture are present. First, the winding frequency response curves of oil-paper insulation were determined by combining insulation aging and moisture tests of the oil-paper insulation with frequency response simulations of the transformer winding. Next, the winding deformation criterion predicting the likelihood and extent of errors diagnosing transformer winding deformations due to the insulation aging and moisture content is discussed. Finally, the corresponding criterion optimization method is proposed. The corresponding results show that insulation aging and moisture can lead to errors when using the correlation coefficient R criterion to diagnose the transformer winding deformations. Moreover, the possibility of winding deformation errors caused by the change of insulation state can be reduced by introducing the corresponding auxiliary criterion through comparing the capacitance change rate based on the frequency response method and that based on the dielectric spectrum method.

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Duncan, Andra E., Andrej Alfirevic, Daniel I. Sessler, Zoran B. Popovic, and James D. Thomas. "Perioperative Assessment of Myocardial Deformation." Anesthesia & Analgesia 118, no. 3 (March 2014): 525–44. http://dx.doi.org/10.1213/ane.0000000000000088.

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Quinn, S., J. M. Dulieu-Barton, J. Eaton-Evans, R. K. Fruehmann, and P. J. Tatum. "Thermoelastic assessment of plastic deformation." Journal of Strain Analysis for Engineering Design 43, no. 6 (June 2008): 451–68. http://dx.doi.org/10.1243/03093247jsa377.

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Xiao, Shi Guo, Qing Rong Yan, and Wen Chen. "Characteristics of Settlement and Assessment Methods of Engineered Structures under Certain High-Speed Railway Tracks in China." Advanced Materials Research 446-449 (January 2012): 1869–79. http://dx.doi.org/10.4028/www.scientific.net/amr.446-449.1869.

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The assessment of settlement deformation of engineered structures under high-speed railway tracks is an important control link in high-speed railway line construction. This paper discusses characteristics of settlement deformation of sections of subgrade, bridges and tunnels, and analyzes the suitability of predictive methods in currently available technical codes and standards based on measured data of settlement deformation. Currently available assessment analysis methods have good applicability for subgrade sections but are not suitable for sections of bridges and tunnels. Suitable assessment analysis methods are proposed and have been successfully applied to settlement deformation of engineered structures under the tracks of high-speed railway lines. The methods suit the characteristics of “small magnitude and large fluctuation” changes of measured settlement deformations taking account of the construction process of the engineered project.

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Bayu Ichsandya, Dimas, Muhammad Dimyati, Iqbal Putut Ash Shidiq, Faris Zulkarnain, Nurul Sri Rahatiningtyas, Riza Putera Syamsuddin, and Farhan Makarim Zein. "Landslide assessment using interferometric synthetic aperture radar in Pacitan, East Java." International Journal of Electrical and Computer Engineering (IJECE) 12, no. 3 (June 1, 2022): 2614. http://dx.doi.org/10.11591/ijece.v12i3.pp2614-2625.

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<span>Landslides are a common type of disaster in Indonesia, especially in steep-slope areas. The landslide process can be well understood by measuring the surface deformation. Currently, there are no practical solutions for measuring surface deformation at landslide locations other than field surveys in the Pacitan Regency. We apply LiCSBAS, to identify surface deformation in several landslide locations in a specific non-urban area with mixed topographical features. LiCSBAS is a module that utilizes data from the project of looking inside the continent from space (LiCS), using the new small baseline area subset (NSBAS) method. This study utilizes the leaf area index (LAI) to validate the ability of LiCSBAS to detect surface deformation values at landslide locations. The study succeeded in identifying surface deformations at 100 landslide locations, with deformation values ranging from 15.1 to 10.9 millimeters per year. Most of the landslide locations are closely related to volcanic rocks and volcanic sediments on slopes of 30–35°. The NSBAS method in the LiCSBAS module can reduce gaps error in the sentinel-1 image network. However, the utilization of the C-band at a pixel size of 100 meters made surface deformation only well detectable in a large open landslide area.</span>

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Volokhov, A. V. "Predictive assessment of the stability of quarry sides." XXI Century. Technosphere Safety 6, no. 2 (July 8, 2021): 201–10. http://dx.doi.org/10.21285/2500-1582-2021-2-201-210.

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The composition of the rocks composing the quarry sides and the approximate slope angles in accordance with the mining and geological conditions are described. The issues of creating observation stations are considered taking into account seasonal temperature fluctuations of the benchmarks. Observation materials are generalized, the degree of danger of deformations is established on the basis of observations of deformation speed. The mining safety control methods are described. The disadvantages of the approach to data processing and analysis are identified. A criterion for mine surveying prediction of the pit wall stability based on the comparison of critical and actual relative deformations is proposed. The purpose of the local forecast of wall deformation is to control the stability of non-working and working slopes of the sides, and to confirm the efficiency of the method used. The predictive assessment was carried out on the shift of working benchmarks on one of the open pits of Transbaikalia. It is suggested monitoring the stability of rocks using oscillograms obtained by seismic equipment.

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Dai, Cong, Weile Li, Huiyan Lu, and Shuai Zhang. "Landslide Hazard Assessment Method Considering the Deformation Factor: A Case Study of Zhouqu, Gansu Province, Northwest China." Remote Sensing 15, no. 3 (January 19, 2023): 596. http://dx.doi.org/10.3390/rs15030596.

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Landslides are geological disasters that can cause great damage to natural and social environments. Landslide hazard assessments are crucial for disaster prevention and mitigation. Conventional regional landslide hazard assessment results are static and do not take into account the dynamic changes in landslides; thus, areas with landslides that have been treated and stabilized are often still identified as high-risk areas. Therefore, a new hazard assessment method is proposed in this paper that combines the deformation rate results obtained by interferometric synthetic aperture radar (InSAR) with the results of conventional hazard assessments to obtain the hazard assessment level while considering the deformation factor of the study area, with Zhouqu, Gansu Province, selected as the case study. First, to obtain the latest landslide inventory map of Zhouqu, the hazard assessment results of the study area were obtained based on a neural network and statistical analysis, and an innovative combination of the deformation rate results of the steepest slope direction from the ascending and descending data were obtained by InSAR technology. Finally, the hazard assessment level considering the deformation factor of Zhouqu was obtained. The method proposed in this paper allows for a near-term hazard assessment of the study area, which in turn enables dynamic regional landslide hazard assessments and improves the efficiency of authorities when conducting high-risk-area identification and management.

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Safta, Voicu Ioan, and Voicu Ionel Safta. "Plastic Deformation and Fracture Initiation Typology Analysis under a Triaxial Tensile State of Stress Using the Quantitative Assessment of Microstructural Changes." Applied Mechanics and Materials 267 (December 2012): 17–24. http://dx.doi.org/10.4028/www.scientific.net/amm.267.17.

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The paper approaches the influence problems, due to increase in plastic deformation and fracture initiation, upon the multi-axial stress state. The experiments are based on determining the geometric changes of stress concentrators and the increase of granulation anisotropy of unalloyed steel related to the plastic deformation. In order to evince the changes in the concentrators shape, at high levels of deformation, an average parameter of shape was introduced. The 3D Complex representations, based on measurements have indicated the dependence of longitudinal specific deformations for the deformation degree, as well as sectional position in the area under measurement. The variation functions of the longitudinal specific deformation of the medium average shape parameter showed an opposed linear dependence at the top of the tension concentrator relatively to the tested specimen axis. Taking into consideration the average parameter of shape, the experimental correlations were more conclusive. Evaluating the microstructural state of stress concentrators, the deformations have revealed distinct fracture typologies, influenced by the specific state of deformation. By synthesizing the information regarding the fracture initiation, an typological diagram of fracture initiation TDI was elaborated. In this diagram, representing the cross section of the specimens, for different values of the stress concentrator factor, six quasi-quantitative zones have been analyzed.

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Dissertations / Theses on the topic "Deformation assessment"

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Al-Hanbali, Nedal Naim. "Assessment of a laser scanning system for deformation monitoring applications." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0006/NQ34654.pdf.

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Damani, Manoj Kumar. "Physics Based Reliability Assessment of Embedded Passives." Thesis, Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/5095.

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Multilayer embedded passives (resistors, inductors, and capacitors) on a printed wiring board can help to meet high performance requirements at a low cost and at a smaller size. Such an integration of embedded passives has new challenges with respect to design, materials, manufacturing, thermal management and reliability. As the area of integral passives on printed circuit boards is relatively new, there is inadequate literature on the thermo-mechanical reliability of integral passives. Therefore, there is a compelling need to understand the thermo-mechanical reliability of integral passives through the development of physics-based models as well as through experiments, and this thesis aims to develop such an experimental and theoretical program to study the thermo-mechanical reliability of integral passives.. As integral passives are often composite layers with dissimilar material properties compared to the other layers in the integral substrate, it is essential to ensure that RLC characteristics of the embedded passives do not deteriorate with thermal cycling due to thermo-mechanical deformations. This thesis aims to study the changes in the passive characteristics due to the thermally-induced deformations. Embedded capacitors and inductors have been looked at specifically in this research. Multi-field physics-based models have been constructed to determine the change in electrical parameters after thermal cycling. The thermo-mechanical models assume direction-dependent material properties for the board substrate and interconnect copper layers and temperature-dependent properties for interlayer dielectric and passive layers. Using the deformed geometry, the electrical characteristics have been determined at low frequency. In parallel to the models, test vehicle substrates have been subjected to 1000 thermal cycles between -55??o 125??nd high humidity and temperature conditions at 85??5RH for 500 hours, and it has been observed that there are significant changes in the electrical parameters. The results obtained from the physics-based simulations have been validated against the measured electrical characteristics from the fabricated functional test boards that have been thermal cycled.

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NAKAMURA, Hikaru, Naoshi UEDA, Minoru KUNIEDA, and Ahmed KAMAL. "ASSESSMENT OF STRENGTHENING EFFECT ON RC BEAMS WITH UHP-SHCC." 日本コンクリート工学会, 2008. http://hdl.handle.net/2237/20917.

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Ceyhan, Ümit [Verfasser]. "High temperature deformation and fracture assessment of similar steel welds / vorgelegt von Ümit Ceyhan." [Clausthal-Zellerfeld] : [Univ.-Bibliothek], 2007. http://d-nb.info/985769653/34.

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Hu, Hui [Verfasser]. "Deformation monitoring and modeling based on LiDAR data for slope stability assessment / Hui Hu." Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2013. http://d-nb.info/103710689X/34.

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Arafa, Ahmed. "Assessment of strength, stiffness, and deformation capacity of concrete squat walls reinforced with GFRP bars." Thèse, Université de Sherbrooke, 2017. http://hdl.handle.net/11143/11057.

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Abstract : The present study addressed the feasibility of reinforced-concrete squat walls totally reinforced with GFRP bars to attain reasonable strength and drift requirements as specified in different codes. Nine large-scale squat walls with aspect ratio (height to length ratio) of 1.33—one reinforced with steel bars (as reference specimen) and eight totally reinforced with GFRP bars—were constructed and tested to failure under quasi-static reversed cyclic lateral loading. The key studied parameters were: (1) use of bidiagonal web reinforcement; (2) use of bidiagonal sliding reinforcement; and (3) web reinforcement configuration (horizontal and/or vertical) and ratio. The reported test results clearly revealed that GFRP-reinforced concrete (RC) squat walls have a satisfactory strength and stable cyclic behavior as well as self-centering ability that assisted in avoiding sliding shear that occurred in the companion steel-reinforced wall following steel yielding. The results are promising regarding using GFRP-reinforced squat walls in areas prone to seismic risk where environmental conditions are adverse to steel reinforcement. Bidiagonal web reinforcement was shown to be more effective than conventional web reinforcement in controlling shear-cracks width. Using bidiagonal sliding reinforcement was demonstrated to be not necessary to prevent sliding shear. The horizontal web reinforcement ratio was found to have a significant effect in enhancing the ultimate strength and deformation capacity as long as the failure is dominant by diagonal tension. Existence of both horizontal and vertical web reinforcement was shown to be essential for cracks recovery. Assessment of the ultimate strengths using the available FRP-reinforced elements code and guidelines (CSA S806-12 and ACI 440.1R-15) was conducted and some recommendations were proposed to attain a reasonable estimation of ultimate strengths. Given their importance in estimating the walls’ later displacement, the effective flexural and shear stiffness of the investigated walls were evaluated. It was found that the cracked shear stiffness could be estimated based on the truss model; while the flexural stiffness can be estimated based on the available expressions in FRP-reinforced elements codes and guidelines. Based on a regression analysis, a simple model that directly correlates the flexural and shear stiffness degradation of the test walls to their top lateral drift was also proposed.
Résumé : La présente étude traite de la faisabilité de voiles courts en béton armé totalement renforcés avec des barres de polymères renforcés de fibres de verre (PRFV), obtenant une résistance et un déplacement latéral raisonnable par rapport aux exigences spécifiées dans divers codes. Neuf voiles à grande échelle ont été construits: un renforcé avec des barres d'acier (comme spécimen de référence) et huit renforcés totalement avec des barres de PRFV. Les voiles ont été testés jusqu’à la rupture sous une charge quasi-statique latérale cyclique inversée. Les voiles ont une hauteur de 2000 mm, une largeur de 1500 mm (élancement 2000 mm/1500 mm = 1,33) et une épaisseur de 200 mm. Les paramètres testés sont : 1) armature bi-diagonale dans l’âme; 2) armature bi-diagonale dans l’encastrement du mur à la fondation (zone de glissement); 3) configuration d’armature verticale et horizontale réparties dans l’âme et taux d’armature. Les résultats des essais ont clairement montré que les voiles courts en béton armé de PRFV ont une résistance satisfaisante et un comportement cyclique stable ainsi qu'une capacité d'auto-centrage qui ont aidé à éviter la rupture par glissement à l’encastrement (sliding shear). Ce mode de rupture (sliding shear) s’est produit pour le voile de référence armé d’acier après la plastification de l’armature. Les résultats sont prometteurs concernant l'utilisation de voiles en béton armé de PRFV dans les régions sismiques dans lesquelles les conditions environnementales sont défavorables à l’armature d’acier (corrosion). L’armature bi-diagonale en PRFV dans l’âme s’est avérée plus efficace pour le contrôle des largeurs de fissures de cisaillement comparativement à l’armature répartie dans l’âme. L'utilisation d'un renforcement de cisaillement bi-diagonal a été démontrée comme n'étant pas nécessaire dans les voiles courts en béton armé de PRFV pour prévenir la rupture par glissement à l’encastrement (shear sliding). Par ailleurs, les résultats d’essais ont montré que le taux d’armature horizontale répartie dans l’âme a un effet significatif sur l’augmentation de la résistance et la capacité en déformation des voiles dont la rupture par effort tranchant se fait par des fissures diagonales (tension failure). L'existence d’armature verticale et horizontale répartie dans l’âme du voile en béton armé de PRFV s'est révélée essentielle pour l’ouverture et la fermeture des fissures au cours des chargements cycliques. Les normes calcul CSA S806-12 et ACI 440.1R-15 ont été utilisées pour évaluer la résistance au cisaillement des voiles courts en béton armé de PRFV. Certaines recommandations ont été proposées pour obtenir une estimation raisonnable des forces ultimes. Compte tenu de leur importance dans l'estimation du déplacement latérale des voiles, la rigidité effective en flexion et en cisaillement des voiles étudiés a été évaluée. On a constaté que la raideur de cisaillement du béton fissuré pourrait être estimée en utilisant le modèle de treillis. La rigidité à la flexion peut être, quant à elle, estimée en fonction des expressions disponibles dans les normes et les guides de conception de membrures en béton armé avec des barres en PRFV. Sur la base d'une analyse de régression, un modèle simple qui corrèle directement la dégradation de la rigidité en flexion et en cisaillement des voiles courts en béton armé de PRFV testés avec le déplacement latérale dans la partie supérieure des voiles a également été proposé.

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Arabshahi, Zohreh. "New mechanical indentation framework for functional assessment of articular cartilage." Thesis, Queensland University of Technology, 2018. https://eprints.qut.edu.au/119696/1/Zohreh_Arabshahi_Thesis.pdf.

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In this research, two new mechanical indentation frameworks were established where the two different indenters (cylindrical and ring-shaped flat-ended indenters) were integrated with ultrasound for assessing functional properties of articular cartilage during loading/unloading. The aim of establishing these framewoks was to address some of the limitations to the conventional indentation techniques. Two new parameters within these frameworks were developed and their capacity to distinguish between normal and different types of cartilage degeneration models during deformation/recovery, was investigated. The ring-shaped flat-ended indenter, integrated with an ultrasound transducer, was shown to be capable of distinguishing normal from artificially degraded bovine osteochondral samples.

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Akturk, Ozgur. "Assessment Of Tunnel Induced Deformation Field Through 3-dimensional Numerical Models (necatibey Subway Station, Ankara, Turkey)." Phd thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612539/index.pdf.

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In heavily settled areas, deformations induced by the tunnel excavation may cause serious damage to nearby structures. In this study it is aimed to model ground deformations induced by main tunnels and connection tunnels excavations as well as groundwater drainage. Therefore, it is necessary to study effective means of controlling tunnel induced deformations. The main parameters affecting the failure and deformation state of the soil around a circular underground opening are the physical characteristics of the soil, the diameter of the opening, and the support pressure. During the construction stage of Necatibey Station of KizilayÇ
ayyolu metro line (Ankara, Turkey), challenging ground conditions involving highly heterogeneous and locally water saturated foundation soils have been encountered. Possibility of damage at the surface and/or on the underground structures can be estimated using finite difference method (FDM) of analysis. In this study, two geophysical methods namely Electrical Resistivity Imaging (ERI) and Ground Penetrating Radar (GPR) were utilized to distinguish soil types at the study area. By correlating these geophysical survey results with the boring v logs, 3-Dimensional soil profile was revealed at the study area to build up a basis for numerical models. 3-Dimensional (3D) FDM analyses were conducted to assess tunneling induced deformations, along with movements around shallow soft ground main tunnels and connection tunnels. During sequential excavations, temporary and permanent shotcrete lining was also simulated. The soil behavior is assumed to be governed by an elastic-perfectly plastic constitutive relation based on the Mohr&ndash
Coulomb criterion. The computed deformations around these openings have been compared with the in-situ measurements. The results of the study revealed that the 3-D elasto-plastic analyses yield comparably good correlation with the in-situ measurements. Also, in this study, the effects of main tunnels excavations on each other and the effects of connection tunnels excavations on main tunnels were identified in terms of ground deformations. In order to simulate induced surface settlement due to groundwater withdrawal at the site 3-D fully coupled (fluidmechanical) numerical models were run using different time durations. The model studies revealed that deformations monitored at the ground surface are directly related with the tunnel construction practice. Pumping groundwater has very little or no effect on the measured deformations.

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Latifi, Kujtim. "Assessment of the Dependence of Ventilation Image Calculation from 4D-CT on Deformation and Ventilation Algorithms." Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3197.

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Ventilation imaging using 4D-CT is a convenient and cost effective functional imaging methodology which might be of value in radiotherapy treatment planning to spare functional lung volumes. To calculate ventilation imaging from 4D-CT we must use deformable image registration (DIR). This study validates the DIR methods and investigates the dependence of calculated ventilation on DIR methods and ventilation algorithms. The first hypothesis is if ventilation algorithms are robust then they will be insensitive to the precise DIR used provided the DIR is accurate. The second hypothesis is that the change in Houndsfield Unit (HU) method is less dependent on the DIR used and depends more on the CT image quality due to the inherent noise of HUs in normal CT imaging. DIR of the normal end expiration and inspiration phases of the 4D-CT images was used to correlate the voxels between the two respiratory phases. All DIR algorithms were validated using a 4D pixel-based and point-validated breathing thorax model, consisting of a 4D-CT image data set along with associated landmarks. Three different DIR algorithms, Optical Flow (OF), Diffeomorphic Demons (DD) and Diffeomorphic Morphons (DM), were retrospectively applied to the same group of 10 esophagus and 10 lung cancer cases all of which had associated 4D-CT image sets that encompassed the entire lung volume. Three different ventilation calculation algorithms were compared (Jacobian, ΔV, and HU) using the Dice similarity coefficient comparison. In the validation of the DIR algorithms, the average target registration errors with one standard deviation for the DIR algorithms were 1.6 ± 0.7 mm, maximum 3.1 mm for OF, 1.3 ± 0.6 mm, maximum 3.3 mm for DM, 1.3 ± 0.6 mm, maximum 2.8 mm for DD, indicating registration errors were within 2 voxels. Dependence of ventilation images on the DIR was greater for the ΔV and the Jacobian methods than for the HU method. The Dice similarity coefficient for 20% of low ventilation volume for ΔV was 0.33 ± 0.03 between OF and DM, 0.44 ± 0.05 between OF and DD and 0.51 ± 0.04 between DM and DD. The similarity comparisons for Jacobian was 0.32 ± 0.03, 0.44 ± 0.05 and 0.51 ± 0.04 respectively, and for HU 0.53 ± 0.03, 0.56 ± 0.03 and 0.76 ± 0.04 respectively. Dependence of ventilation images on the ventilation method used showed good agreement between the ΔV and Jacobian methods but differences between these two and the HU method were significantly greater. Dice similarity coefficient for using OF as DIR was 0.86 ± 0.01 between ΔV and Jacobian, 0.28 ± 0.04 between ΔV and HU and 0.28 ± 0.04 between Jacobian and HU respectively. When using DM or DD as DIR, similar values were obtained when comparing the different ventilation calculation methods. The similarity values for 20% of the high ventilation volume were close to those found for the 20% low ventilation volume. Mean target registration error for all three DIR methods was within one voxel suggesting that the registration done by either of the methods is quite accurate. Ventilation calculation from 4D-CT demonstrates some degree of dependency on the DIR algorithm employed. Similarities between ΔV and Jacobian are higher than between ΔV and HU and Jacobian and HU. This shows that ΔV and Jacobian are very similar, but HU is a very different ventilation calculation method.

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Kim, YuJaung. "ASSESSMENT OF CIRCUMFERENTIAL MYOCARDIAL FUNCTION USING RADIAL TAGGED MRI." Cleveland State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=csu1331005696.

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Books on the topic "Deformation assessment"

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Hasegawa, Hideyuki. Ultrasonic methods for measurement of small motion and deformation of biological tissues for assessment of viscoelasticity. New York, NY, USA: ASME, 2014.

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J, Ghosn L., and Lewis Research Center, eds. An assessment of the axial and radial dilation of a DPIMS tantalum cartridge for space shuttle flight experiments. [Cleveland, Ohio]: National Aeronautics and Space Administration, Lewis Research Center, 1998.

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E, Wilt Thomas, and United States. National Aeronautics and Space Administration., eds. Final technical report for the development of computational techniques for the nonlinear analysis of composite structures at high temperature: NASA grant number, NCC3-248, grant duration, January 13, 1992 to March 1, 1995. Toledo, Ohio: Dept. of Mechnical, Industrial and Manufacturing Engineering, University of Toledo, 1996.

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Wyss, Max. Earthquake Risk Assessment. Oxford University Press, 2017. http://dx.doi.org/10.1093/oxfordhb/9780190676889.013.1.

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This article discusses the importance of assessing and estimating the risk of earthquakes. It begins with an overview of earthquake prediction and relevant terms, namely: earthquake hazard, maximum credible earthquake magnitude, exposure time, earthquake risk, and return time. It then considers data sources for estimating seismic hazard, including catalogs of historic earthquakes, measurements of crustal deformation, and world population data. It also examines ways of estimating seismic risk, such as the use of probabilistic estimates, deterministic estimates, and the concepts of characteristic earthquake, seismic gap, and maximum rupture length. A loss scenario for a possible future earthquake is presented, and the notion of imminent seismic risk is explained. Finally, the chapter addresses errors in seismic risk estimates and how to reduce seismic risk, ethical and moral aspects of seismic risk assessment, and the outlook concerning seismic risk assessment.

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Wyss, Max. Earthquake Risk Assessment. Oxford University Press, 2017. http://dx.doi.org/10.1093/oxfordhb/9780190699420.013.1.

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This article discusses the importance of assessing and estimating the risk of earthquakes. It begins with an overview of earthquake prediction and relevant terms, namely: earthquake hazard, maximum credible earthquake magnitude, exposure time, earthquake risk, and return time. It then considers data sources for estimating seismic hazard, including catalogs of historic earthquakes, measurements of crustal deformation, and world population data. It also examines ways of estimating seismic risk, such as the use of probabilistic estimates, deterministic estimates, and the concepts of characteristic earthquake, seismic gap, and maximum rupture length. A loss scenario for a possible future earthquake is presented, and the notion of imminent seismic risk is explained. Finally, the chapter addresses errors in seismic risk estimates and how to reduce seismic risk, ethical and moral aspects of seismic risk assessment, and the outlook concerning seismic risk assessment.

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Aguilar-Torres, Río. Assessment of left atrial function. Oxford University Press, 2011. http://dx.doi.org/10.1093/med/9780199599639.003.0010.

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The left atrium (LA) plays an important role in cardiovascular performance, not only as a mechanical contributor, elastic reservoir, and a primer for left ventricular filling, but also as a participant in the regulation of intravascular volume through the production of atrial natriuretic peptide.Although LA diameter in the parasternal long-axis view has been routinely employed, LA volume is a more robust marker for predicting events than LA areas or diameters. The assessment of LA performance based on two-dimensional volumetrics, Doppler evaluation of mitral, pulmonary vein flow, and annular tissue Doppler, as well as deformation imaging techniques, may provide incremental information for prognostic purposes and for the evaluation of severity and duration of conditions associated with LA overload.The aims of this chapter are to explain the basics of LA function, and to describe the role of Doppler echocardiography techniques, and how to implement them, for the non-invasive evaluation of LA in clinical practice.

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Hasegawa, H., and H. Kanai, eds. Ultrasonic Methods for Measurement of Small Motion and Deformation of Biological Tissues for Assessment of Viscoelasticity. ASME Press, 2014. http://dx.doi.org/10.1115/1.860311.

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Kanai, Hiroshi, and Hideyuki Hasegawa. Ultrasonic Methods for Measurement of Small Motion and Deformation of Biological Tissues for Assessment of Viscoelasticity. Momentum Press, 2014.

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Donal, Erwan, Seisyou Kou, and Partho Senguptadd. Left ventricle: cardiac mechanics and left ventricular performance. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780198726012.003.0019.

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The complexity of left ventricular (LV) function(s) assessment in heart failure patients is related to the complexity of heart anatomy, but also to the complexity of electromechanical interaction, and to the load dependency of all the parameters that could be applied in clinical practice. Three perpendicular axes orienting the global geometry of the LV define the local cardiac coordinate system: radial, circumferential, and longitudinal. Speckle tracking is the technique of choice for quantifying myocardial deformation (regional and global). Longitudinal LV deformation, which is predominantly governed by the subendocardial region, is the most vulnerable component of LV mechanics and therefore most sensitive to the presence of myocardial disease.

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Voigt, Jens-Uwe. Quantification of left ventricular function and synchrony using tissue Doppler, strain imaging, and speckle tracking. Oxford University Press, 2011. http://dx.doi.org/10.1093/med/9780199599639.003.0006.

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Modern echocardiographic systems allow the quantitative and qualitative assessment of regional myocardial function by measuring velocity, motion, deformation, and other parameters of myocardial function.Both colour Doppler (CD) and spectral Doppler modes provide one-dimensional estimates of velocity. From CD data only, further parameters can be derived. Tracking techniques have recently been introduced which provide all parameters two-dimensionally, but at the cost of lower temporal resolution.Several clinical applications have been proposed, including regional and global systolic function assessment, evaluation of diastolic cardiac properties, and assessment of ventricular dyssynchrony.This chapter provides an introduction to the method of Doppler- and tracking-based function assessment and provides a basis for understanding its different clinical applications.

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Book chapters on the topic "Deformation assessment"

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Webster, G. A., and R. A. Ainsworth. "Processes of deformation and fracture at high temperatures." In High Temperature Component Life Assessment, 10–49. Dordrecht: Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-017-1771-7_2.

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Biskinis, Dionysis, and Michael N. Fardis. "Upgrading of Resistance and Cyclic Deformation Capacity of Deficient Concrete Columns." In Seismic Risk Assessment and Retrofitting, 307–28. Dordrecht: Springer Netherlands, 2009. http://dx.doi.org/10.1007/978-90-481-2681-1_15.

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Weglein, R. D. "Quantitative Assessment of Plastic Deformation Via Acoustic Microscopy." In Review of Progress in Quantitative Nondestructive Evaluation, 2137–44. Boston, MA: Springer US, 1993. http://dx.doi.org/10.1007/978-1-4615-2848-7_274.

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Zhu, Hanhua, and Mengchong Chen. "Deformation Compatibility Control Technique for Foundation Pits." In Stability Assessment for Underground Excavations and Key Construction Techniques, 143–57. Singapore: Springer Singapore, 2016. http://dx.doi.org/10.1007/978-981-10-3011-6_6.

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Makhutov, Nikolay A., and Michael M. Gadenin. "Non-Linear Deformation and Fatigue Fracture in Engineering Design." In Reliability Assessment of Cyclically Loaded Engineering Structures, 273–300. Dordrecht: Springer Netherlands, 1997. http://dx.doi.org/10.1007/978-94-011-5556-4_9.

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Parker, Amy Laura. "Systematic Assessment of Atmospheric Uncertainties for InSAR Data at Volcanic Arcs Using Large-Scale Atmospheric Models: Application to the Cascade Volcanoes." In InSAR Observations of Ground Deformation, 59–90. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-39034-5_3.

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Ružička, Pavel, Jan Rýdel, Miroslav Josefik, Fritz Boden, and Claudio Lanari. "Assessment of Propeller Deformation Measurement Techniques for Industrial Application." In Research Topics in Aerospace, 155–68. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-34738-2_10.

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Padmanabhan, K. A., S. Balasivanandha Prabu, R. R. Mulyukov, Ayrat Nazarov, R. M. Imayev, and S. Ghosh Chowdhury. "Mechanics of Superplastic Deformation and Assessment of Superplastic Behavior." In Superplasticity, 13–57. Berlin, Heidelberg: Springer Berlin Heidelberg, 2018. http://dx.doi.org/10.1007/978-3-642-31957-0_2.

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Hill, Derek L. G., Calvin R. Maurer, Alastair J. Martin, Saras Sabanathan, Walter A. Hall, David J. Hawkes, Daniel Rueckert, and Charles L. Truwit. "Assessment of Intraoperative Brain Deformation Using Interventional MR Imaging." In Medical Image Computing and Computer-Assisted Intervention – MICCAI’99, 910–19. Berlin, Heidelberg: Springer Berlin Heidelberg, 1999. http://dx.doi.org/10.1007/10704282_99.

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Akkar, Sinan, and Haluk Sucuoglu. "Peak Ground Velocity Sensitive Deformation Demands and a Rapid Damage Assessment Approach." In Seismic Assessment and Rehabilitation of Existing Buildings, 77–96. Dordrecht: Springer Netherlands, 2003. http://dx.doi.org/10.1007/978-94-010-0021-5_6.

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Conference papers on the topic "Deformation assessment"

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"Assessment of Water Migration Distance in Internal Curing of High-Strength Concrete." In SP-220: Autogenous Deformation of Concrete. American Concrete Institute, 2004. http://dx.doi.org/10.14359/13157.

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Sloboda, Andrew R., and Chin Ting Kong. "Damage Assessment From Attractor Boundary Deformation." In ASME 2022 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/smasis2022-88793.

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Abstract Quantifying damage in nonlinear systems remains challenging. Existing methods using chaotic interrogation are limited because they are based on algorithms designed for time series prediction and have difficulty determining damage type or location. To address this shortcoming, we propose analysis based on exciting a structure with a chaotic signal and then measuring changes in the outer boundary of the chaotic attractor associated with the structural response. Sampling the boundaries of attractors associated with both the undamaged and damaged structures allows boundary transformation vectors (BTVs) to be drawn between the boundaries that encode information about how the system has changed. Certain regions of the boundary will deform proportionally to damage level, but these regions may be situated differently or deform in different directions for different damage types or locations, allowing this additional information to be inferred. If a library of BTVs for known damage cases are recorded, then future, unknown damage can be quantified using interpolation or extrapolation of the library. A simulated mass-spring-damper system is used to demonstrate how both damage level and type/location can be determined using chaotic interrogation in combination with boundary transformation analysis.

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Psimoulis, Panos, Ali Algadhi, Athina Grizi, and Luis Neves. "Assessment of accuracy and performance of terrestrial laser scanner in monitoring of retaining walls." In 5th Joint International Symposium on Deformation Monitoring. Valencia: Editorial de la Universitat Politècnica de València, 2022. http://dx.doi.org/10.4995/jisdm2022.2022.13917.

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Retaining walls are a critical infrastructure of transportation networks and the monitoring of their condition is crucial for the efficient and reliable maintenance of the network. The condition of retaining walls is frequently assessed using qualitative criteria and visual inspection, which are susceptible to human-bias and errors. To improve the management of these structures, reducing the probability of failure and the maintenance costs, it is critical to develop more efficient, reliable and quantitative monitoring approaches for these structures. The current study aims to evaluate the performance of Terrestrial Laser Scanner (TLS) in deformation monitoring of retaining walls, based on the analysis of single scans (without registering the point clouds to build 3D models). The evaluation was based on a controlled experiment, where a wooden frame (1.5m x 1m) was used to simulate deformation scenarios for retaining walls, with an amplitude between 2 to 16 mm. A Leica RTC360 scanner was used to scan the wooden frame from distances varying between 10 to 27 m and angles varying between 0° to 20°. Five methods were applied to analyse the laser-scanner data and estimate the displacement: a target-based approach and four cloud-based approaches including the Cloud-to-Cloud (C2C), the Cloud-to-Mesh (C2M), the Multiscale-Model-to-Model-Cloud-Comparison (M3C2), and an alternative cloud-based method where the mean average of the point-cloud was used to estimate the displacement in the axis of the deformation. A Robotic Total Station Leica TS30 was also used to measure the deformation of the wooden frame and provide the ground truth values of the introduced deformation for each scenario. The results showed that the RTC360 had an accuracy of 1.3 mm with a confidence level of 95%.

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Culek, B., V. Dolezel, and P. P. Prochazka. "Probabilistic Assessment of a Railway Steel Bridge." In 9th International Conference On Analysis of Discontinues Deformation: New Developments and Applications. Singapore: Research Publishing Services, 2009. http://dx.doi.org/10.3850/9789810844554-0136.

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Dogan, Bilal. "Creep Deformation and Failure Assessment of Steel Weldments." In ASME 2007 Pressure Vessels and Piping Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/creep2007-26275.

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The effect of weldments in service performance of high temperature components has been subject to intensive research due to the fact that in the majority of cases where high temperature failure occurs, defects predominate in the vicinity of weldments. Cracking occurs in service due to reduced creep ductility of HAZ and weld metal due to ageing in service, combined with the action of multi-axial stress fields that reduce the creep ductility further. The defects detected or assumed to exist through minimum allowable limits of detectable flaws using non-destructive testing methods is required for structural integrity and residual life assessment of high temperature components. The assessment relies on information obtained from the material’s high temperature tensile, uniaxial creep, crack initiation and growth properties. The concepts used for time dependent fracture analysis of homogeneous bodies are commonly applied for creep crack growth in weldments that show multi-crack initiation and crack branching. This calls for study of deformation behavior and applicability of fracture mechanics parameters for high temperature assessment of weldments. The present paper reports on the material behavior and methodology followed for testing and assessment of the high temperature steel weldments.

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Jing, Yixiong, Brian Sheil, and Sinan Acikgoz. "Extraction of key geometric parameters from segmented masonry arch bridge point clouds." In 5th Joint International Symposium on Deformation Monitoring. Valencia: Editorial de la Universitat Politècnica de València, 2022. http://dx.doi.org/10.4995/jisdm2022.2022.13814.

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Masonry arch bridges constitute the majority of the European bridge stock. Most of these bridges were constructed in the 19th century and feature a wide range of geometric characteristics. Since construction drawings rarely exist, the first step in the assessment of these bridges is the characterisation of their in-situ geometry, which may involve significant geometric distortions. In recent years, LIDAR devices have been widely used by bridge owners due to their ability to remotely and rapidly collect point cloud data. To enable the engineering assessment practice to benefit from this data, this research uses the recently developed deep learning (DL) neural network BridgeNet to autonomously segment masonry bridge point clouds into different components. Due to the limited availability of 3D point clouds, BridgeNet is trained using a synthetic multi-span masonry arch bridge dataset; the network is then tested on real arch bridge point clouds. By fitting appropriate primitive shapes to bridge component point clouds using Random Consensus Sampling (RANSAC) techniques the bridge geometry is effectively characterised by a few parameters.

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Keller, Jürgen, Astrid Gollhardt, Dietmar Vogel, and Bernd Michel. "Nanoscale deformation measurements for reliability assessment of material interfaces." In Nondestructive Evaulation for Health Monitoring and Diagnostics, edited by Robert E. Geer, Norbert Meyendorf, George Y. Baaklini, and Dietmar W. Vogel. SPIE, 2006. http://dx.doi.org/10.1117/12.658637.

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Lei, Jun, Dong Xu, and José Turmo. "Compatible Deformation in the Condition Assessment of Beam Structures." In IABSE Symposium, Nantes 2018: Tomorrow’s Megastructures. Zurich, Switzerland: International Association for Bridge and Structural Engineering (IABSE), 2018. http://dx.doi.org/10.2749/nantes.2018.s24-79.

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S., Gopalakrishna, Jayashankar V., Jagadeesh Kumar V., and Madhu Mohan N. "Online assessment of winding deformation based on optimised excitation." In 2010 IEEE International Workshop on Applied Measurements for Power Systems (AMPS 2010). IEEE, 2010. http://dx.doi.org/10.1109/amps.2010.5609322.

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Perlea, V. G., D. C. Serafini, S. Salah-Mars, and F. I. Makdisi. "Seismic Deformation Analysis for Risk Assessment of Embankment Dams." In Geo-Frontiers Congress 2011. Reston, VA: American Society of Civil Engineers, 2011. http://dx.doi.org/10.1061/41165(397)326.

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Reports on the topic "Deformation assessment"

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Babuska, I., K. Jerina, Y. Li, and P. Smith. Quantitative Assessment of the Accuracy of Constitutive Laws for Plasticity with an Emphasis on Cyclic Deformation. Fort Belvoir, VA: Defense Technical Information Center, April 1993. http://dx.doi.org/10.21236/ada267562.

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McNeill, Stephen R., Michael A. Sutton, and Hugh A. Bruck. Characterization and Model Assessment for Impact Damage Evolution in Functionally Graded Composites Using a Novel Nanosecond Deformation Measurement System. Fort Belvoir, VA: Defense Technical Information Center, April 2006. http://dx.doi.org/10.21236/ada455458.

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Al-Qadi, Imad, Jaime Hernandez, Angeli Jayme, Mojtaba Ziyadi, Erman Gungor, Seunggu Kang, John Harvey, et al. The Impact of Wide-Base Tires on Pavement—A National Study. Illinois Center for Transportation, October 2021. http://dx.doi.org/10.36501/0197-9191/21-035.

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Researchers have been studying wide-base tires for over two decades, but no evidence has been provided regarding the net benefit of this tire technology. In this study, a comprehensive approach is used to compare new-generation wide-base tires (NG-WBT) with the dual-tire assembly (DTA). Numerical modeling, prediction methods, experimental measurements, and environmental impact assessment were combined to provide recommendations about the use of NG-WBT. A finite element approach, considering variables usually omitted in the conventional analysis of flexible pavement was utilized for modeling. Five hundred seventy-six cases combining layer thickness, material properties, tire load, tire inflation pressure, and pavement type (thick and thin) were analyzed to obtained critical pavement responses. A prediction tool, known as ICT-Wide, was developed based on artificial neural networks to obtain critical pavement responses in cases outside the finite element analysis matrix. The environmental impacts were determined using life cycle assessment. Based on the bottom-up fatigue cracking, permanent deformation, and international roughness index, the life cycle energy consumption, cost, and green-house gas (GHG) emissions were estimated. To make the outcome of this research effort useful for state departments of transportation and practitioners, a modification to AASHTOWare is proposed to account for NG-WBT. The revision is based on two adjustment factors, one accounting for the discrepancy between the AASHTOware approach and the finite element model of this study, and the other addressing the impact of NG-WBT.

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Yan, Yujie, and Jerome F. Hajjar. Automated Damage Assessment and Structural Modeling of Bridges with Visual Sensing Technology. Northeastern University, May 2021. http://dx.doi.org/10.17760/d20410114.

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Recent advances in visual sensing technology have gained much attention in the field of bridge inspection and management. Coupled with advanced robotic systems, state-of-the-art visual sensors can be used to obtain accurate documentation of bridges without the need for any special equipment or traffic closure. The captured visual sensor data can be post-processed to gather meaningful information for the bridge structures and hence to support bridge inspection and management. However, state-of-the-practice data postprocessing approaches require substantial manual operations, which can be time-consuming and expensive. The main objective of this study is to develop methods and algorithms to automate the post-processing of the visual sensor data towards the extraction of three main categories of information: 1) object information such as object identity, shapes, and spatial relationships - a novel heuristic-based method is proposed to automate the detection and recognition of main structural elements of steel girder bridges in both terrestrial and unmanned aerial vehicle (UAV)-based laser scanning data. Domain knowledge on the geometric and topological constraints of the structural elements is modeled and utilized as heuristics to guide the search as well as to reject erroneous detection results. 2) structural damage information, such as damage locations and quantities - to support the assessment of damage associated with small deformations, an advanced crack assessment method is proposed to enable automated detection and quantification of concrete cracks in critical structural elements based on UAV-based visual sensor data. In terms of damage associated with large deformations, based on the surface normal-based method proposed in Guldur et al. (2014), a new algorithm is developed to enhance the robustness of damage assessment for structural elements with curved surfaces. 3) three-dimensional volumetric models - the object information extracted from the laser scanning data is exploited to create a complete geometric representation for each structural element. In addition, mesh generation algorithms are developed to automatically convert the geometric representations into conformal all-hexahedron finite element meshes, which can be finally assembled to create a finite element model of the entire bridge. To validate the effectiveness of the developed methods and algorithms, several field data collections have been conducted to collect both the visual sensor data and the physical measurements from experimental specimens and in-service bridges. The data were collected using both terrestrial laser scanners combined with images, and laser scanners and cameras mounted to unmanned aerial vehicles.

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Wilson, A. M., and M. C. Kelman. Assessing the relative threats from Canadian volcanoes. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/328950.

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This report presents an analysis of the threat posed by active volcanoes in Canada and outlines directives to bring Canadian volcano monitoring and research into alignment with global best practices. We analyse 28 Canadian volcanoes in terms of their relative threat to people, aviation and infrastructure. The methodology we apply to assess volcanic threat was developed by the United States Geological Survey (USGS) as part of the 2005 National Volcano Early Warning System (NVEWS). Each volcano is scored on a number of hazard and exposure factors, producing an overall threat score. The overall threat scores are then assigned to five threat categories ranging from Very Low to Very High. We adjusted the methodology slightly to better suit Canadian volcano conditions by adding an additional knowledge uncertainty score; this does not affect the threat scoring or ranking. Our threat assessment places two volcanoes into the Very High threat category (Mt. Meager and Mt. Garibaldi). Three Canadian volcanoes score in the High threat category (Mt. Cayley, Mt. Price and Mt. Edziza) and two volcanoes score in the Moderate threat category (the Nass River group and Mt. Silverthrone). We compare the ranked Canadian volcanoes to similarly scored volcanoes in the USA and assess the current levels of volcano monitoring against internationally recognised monitoring strategies. We find that even the most thoroughly-studied volcano in Canada (Mt. Meager) falls significantly short of the recommended monitoring level (Mt. Meager is currently monitored at a level commensurate with a Very Low threat edifice, according to NVEWS recommendations). All other Canadian volcanoes are unmonitored (other than falling within a regional seismic network emplaced to monitor tectonic earthquakes). Based on the relative threat and scientific uncertainty surrounding some Canadian volcanoes, we outline five strategies to improve volcano monitoring in Canada and lower the uncertainty about eruption style and frequency: installation of real-time seismic stations at all Very High and High threat volcanoes, comprehensive lithofacies studies at Mt. Garibaldi in order to reduce uncertainty surrounding the frequency and style of volcanism, hazard mapping at Mt. Garibaldi and Mt. Cayley and publication of existing hazard analyses and mapping for Mt. Meager as a comprehensive hazard map, regular satellite-based ground deformation monitoring at all Very High to Moderate threat edifices, and, finally, installation of a landslide detection and alerting system at Mt. Meager.

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Wilson, A. M., and M. C. Kelman. Assessing the relative threats from Canadian volcanoes. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/328950.

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This report presents an analysis of the threat posed by active volcanoes in Canada and outlines directives to bring Canadian volcano monitoring and research into alignment with global best practices. We analyse 28 Canadian volcanoes in terms of their relative threat to people, aviation and infrastructure. The methodology we apply to assess volcanic threat was developed by the United States Geological Survey (USGS) as part of the 2005 National Volcano Early Warning System (NVEWS). Each volcano is scored on a number of hazard and exposure factors, producing an overall threat score. The overall threat scores are then assigned to five threat categories ranging from Very Low to Very High. We adjusted the methodology slightly to better suit Canadian volcano conditions by adding an additional knowledge uncertainty score; this does not affect the threat scoring or ranking. Our threat assessment places two volcanoes into the Very High threat category (Mt. Meager and Mt. Garibaldi). Three Canadian volcanoes score in the High threat category (Mt. Cayley, Mt. Price and Mt. Edziza) and two volcanoes score in the Moderate threat category (the Nass River group and Mt. Silverthrone). We compare the ranked Canadian volcanoes to similarly scored volcanoes in the USA and assess the current levels of volcano monitoring against internationally recognised monitoring strategies. We find that even the most thoroughly-studied volcano in Canada (Mt. Meager) falls significantly short of the recommended monitoring level (Mt. Meager is currently monitored at a level commensurate with a Very Low threat edifice, according to NVEWS recommendations). All other Canadian volcanoes are unmonitored (other than falling within a regional seismic network emplaced to monitor tectonic earthquakes). Based on the relative threat and scientific uncertainty surrounding some Canadian volcanoes, we outline five strategies to improve volcano monitoring in Canada and lower the uncertainty about eruption style and frequency: installation of real-time seismic stations at all Very High and High threat volcanoes, comprehensive lithofacies studies at Mt. Garibaldi in order to reduce uncertainty surrounding the frequency and style of volcanism, hazard mapping at Mt. Garibaldi and Mt. Cayley and publication of existing hazard analyses and mapping for Mt. Meager as a comprehensive hazard map, regular satellite-based ground deformation monitoring at all Very High to Moderate threat edifices, and, finally, installation of a landslide detection and alerting system at Mt. Meager.

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THE CONTINUOUS STRENGTH METHOD – REVIEW AND OUTLOOK. The Hong Kong Institute of Steel Construction, August 2022. http://dx.doi.org/10.18057/icass2020.p.k11.

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The Continuous Strength Method (CSM) is a deformation-based approach to the design of structures that enables a continuous, rational and accurate allowance for material nonlinearity. Central to the method is the application of strain limits to define the resistance of a structural member or system.The method can be applied to structures formed using different materials and manufacturing processes and can be used for steel-concrete composite design and in fire scenarios. The design method enables enhancements in structural efficiency and, unlike traditional approaches, allows the assessment of both strength and ductility demands (particularly relevant for high strength steel) at the ultimate limit state. For hand calculations, a set of straightforward CSM design equations have been developed. Recognising the increasing importance and use of advanced analysis, recent research, summarised herein, has focused on integration of the CSM strain limits into a framework of design by second order inelastic analysis, where the benefits of the method become even more substantial. This paper provides a review of the background and recent developments, including incorporation into design standards.

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