scholarly journals Estimation of three-dimensional crustal movements in the 2011 Tohoku-Oki, Japan, earthquake from TerraSAR-X intensity images

2015 ◽  
Vol 15 (3) ◽  
pp. 637-645 ◽  
Author(s):  
W. Liu ◽  
F. Yamazaki ◽  
M. Matsuoka ◽  
T. Nonaka ◽  
T. Sasagawa
Keyword(s):  
Three Dimensional ◽  
Synthetic Aperture ◽  
Sar Images ◽  
Crustal Movements ◽  
Surface Displacements ◽  
Time Period ◽  
Intensity Images ◽  
Short Time ◽  
The Relationship ◽  
Gps Observations

Abstract. The Tohoku-Oki earthquake on 11 March 2011 caused significant widespread crustal movements. In a previous study, we proposed a method for capturing two-dimensional (2-D) surface displacements from a pair of pre- and post-event TerraSAR-X (TSX) intensity images. However, it is impossible to detect three-dimensional (3-D) displacements from one pair of TSX images. In this study, three pairs of pre- and post-event TSX images taken on different paths were used to estimate 3-D crustal movements. The relationship between the actual 3-D displacements and the converted 2-D movements in the synthetic-aperture radar (SAR) images was derived based on the observation model of a SAR sensor. The 3-D movements were then calculated from three sets of detected 2-D movements that occurred within a short time period. Compared with GPS observations, the proposed method was found to be capable of detecting the 3-D crustal movements with sub-pixel accuracy.

scholarly journals Estimation of three-dimensional crustal movements in the 2011 Tohoku-oki, Japan earthquake from TerraSAR-X intensity images

2014 ◽  
Vol 2 (12) ◽  
pp. 7383-7408
Author(s):  
W. Liu ◽  
F. Yamazaki ◽  
M. Matsuoka ◽  
T. Nonaka ◽  
T. Sasagawa
Keyword(s):  
Three Dimensional ◽  
Short Time Period ◽  
Sar Images ◽  
Crustal Movements ◽  
Surface Displacements ◽  
Time Period ◽  
Intensity Images ◽  
Short Time ◽  
The Relationship ◽  
Gps Observations

Abstract. The Tohoku-Oki earthquake on 11 March 2011 caused significant widespread crustal movements. In a previous study, we proposed a method for capturing two-dimensional (2-D) surface displacements from a pair of pre- and post-event TerraSAR-X (TSX) intensity images. However, it is difficult to detect three-dimensional (3-D) displacements from one pair of TSX images. In this study, three pairs of pre- and post-event TSX images taken on different paths were used to estimate 3-D crustal movements. The relationship between the actual 3-D displacements and the converted 2-D movements in the SAR images was derived based on the observation model of a SAR sensor. The 3-D movements were then calculated from three sets of detected 2-D movements that occurred within a short time period. Compared with GPS observations, the proposed method was found to be capable of detecting the 3-D crustal movements with sub-pixel accuracy.

THEORETICAL GROUNDS FOR ANGULAR CORRECTION OF THE SUPPLY AIR JET FLOW VECTOR IN THE VENTILATION SYSTEMS OF INDUSTRIAL AND AGRICULTURAL FACILITIES

2021 ◽  
pp. 25-30
Author(s):  
IVAN YU. IGNATKIN ◽  
Keyword(s):  
Inclination Angle ◽  
Three Dimensional ◽  
Control Unit ◽  
Climate Control ◽  
Axisymmetric Jet ◽  
Air Jet ◽  
Time Period ◽  
Free Air ◽  
Angular Correction ◽  
The Relationship

During the heating period, the supply air temperature is lower than that in industrial premises, and the cooled air is denser. Entering a warm room, it tends to move downward. This condition leads to the formation of chilled and stagnant zones. The article presents a theoretical study on the possibility of ensuring the maximum propagation range of a non-isothermal supply air jet by angular correction of the fl ow vector at the outlet of the ventilation unit. Based on the theory of free air distribution, the author analyzed and graphically visualized the fl ow trajectories of the supply air from the combined climate control unit with heat recovery in the production room in the range of outdoor temperatures from +10 to –40°C. Given the time period of outdoor temperatures, fl at sections of a three-dimensional graph were built with a step of 10°C in the range from +10 to –30°C. The author found that the maximum service area of the installation is limited by the propagation range of the supply air jet. The area can be increased by changing the direction of the fl ow vector by an angle ranging between 0 and 34°. The value of the inclination angle of the fl ow vector of the supply air jet is determined by the obtained approximation dependency. Considering the regulation of the fl ow vector, the author used the formula of M.Z. Pechatnikov to determine the propagation range of a limited axisymmetric jet. The studies carried out made it possible to establish the relationship between the propagation range of the supply air jet of the installation and the outside temperature, the inclination angle of the fl ow vector, and the theoretical variation range of the inclination angle of the fl ow vector, ranging between 0 and 34°.

THEORETICAL GROUNDS FOR ANGULAR CORRECTION OF THE SUPPLY AIR JET FLOW VECTOR IN THE VENTILATION SYSTEMS OF INDUSTRIAL AND AGRICULTURAL FACILITIES

2021 ◽  
pp. 20-24
Author(s):  
VIKTOR N. OZHERELYEV ◽  
Keyword(s):  
Inclination Angle ◽  
Three Dimensional ◽  
Control Unit ◽  
Climate Control ◽  
Axisymmetric Jet ◽  
Air Jet ◽  
Time Period ◽  
Free Air ◽  
Angular Correction ◽  
The Relationship

During the heating period, the supply air temperature is lower than that in industrial premises, and the cooled air is denser. Entering a warm room, it tends to move downward. This condition leads to the formation of chilled and stagnant zones. The article presents a theoretical study on the possibility of ensuring the maximum propagation range of a non-isothermal supply air jet by angular correction of the fl ow vector at the outlet of the ventilation unit. Based on the theory of free air distribution, the author analyzed and graphically visualized the fl ow trajectories of the supply air from the combined climate control unit with heat recovery in the production room in the range of outdoor temperatures from +10 to –40°C. Given the time period of outdoor temperatures, fl at sections of a three-dimensional graph were built with a step of 10°C in the range from +10 to –30°C. The author found that the maximum service area of the installation is limited by the propagation range of the supply air jet. The area can be increased by changing the direction of the fl ow vector by an angle ranging between 0 and 34°. The value of the inclination angle of the fl ow vector of the supply air jet is determined by the obtained approximation dependency. Considering the regulation of the fl ow vector, the author used the formula of M.Z. Pechatnikov to determine the propagation range of a limited axisymmetric jet. The studies carried out made it possible to establish the relationship between the propagation range of the supply air jet of the installation and the outside temperature, the inclination angle of the fl ow vector, and the theoretical variation range of the inclination angle of the fl ow vector, ranging between 0 and 34°.

Auditory–visual speech perception in three- and four-year-olds and its relationship to perceptual attunement and receptive vocabulary

2017 ◽  
Vol 45 (2) ◽  
pp. 273-289 ◽  
Author(s):  
DOĞU ERDENER ◽  
DENIS BURNHAM
Keyword(s):  
Speech Perception ◽  
Native Language ◽  
The Body ◽  
Receptive Vocabulary ◽  
Visual Speech ◽  
Time Period ◽  
Visual Speech Perception ◽  
English Speaking ◽  
Short Time ◽  
The Relationship

AbstractDespite the body of research on auditory–visual speech perception in infants and schoolchildren, development in the early childhood period remains relatively uncharted. In this study, English-speaking children between three and four years of age were investigated for: (i) the development of visual speech perception – lip-reading and visual influence in auditory–visual integration; (ii) the development of auditory speech perception and native language perceptual attunement; and (iii) the relationship between these and a language skill relevant at this age, receptive vocabulary. Visual speech perception skills improved even over this relatively short time period. However, regression analyses revealed that vocabulary was predicted by auditory-only speech perception, and native language attunement, but not by visual speech perception ability. The results suggest that, in contrast to infants and schoolchildren, in three- to four-year-olds the relationship between speech perception and language ability is based on auditory and not visual or auditory–visual speech perception ability. Adding these results to existing findings allows elaboration of a more complete account of the developmental course of auditory–visual speech perception.

scholarly journals Analysis of tectonic activity of the North Anatolian Fault based on SBInSAR method

2018 ◽  
Vol 55 ◽  
pp. 00005 ◽  
Author(s):  
Karolina Owczarz
Keyword(s):  
North Anatolian Fault ◽  
Synthetic Aperture ◽  
Tectonic Activity ◽  
Sar Images ◽  
Synthetic Aperture Radar Interferometry ◽  
The North ◽  
Tectonic Faults ◽  
Surface Displacements ◽  
Active Tectonic ◽  
Small Baseline

The North Anatolian Fault situated in Turkey is one of the longest and most active tectonic faults in the world. The paper presents an analysis of tectonic activity in its area based on the method of Small Baseline Synthetic Aperture Radar Interferometry. For this purpose 73 satellite SAR images and specialized software GMT5SAR were used with implement the SBAS algorithm. In addition, the most important aspects of data processing and their final products were presented, which determined the surface displacements occurring in the surveyed area from 1 January 2014 to 1 March 2017. The displacements of the SBAS surface area ranged from -10 cm to +10 cm. Based on the obtained results and their analysis, the author also assessed the suitability of SBInSAR technology for areas of land displacement.

scholarly journals 3D SAR Speckle Offset Tracking Potential for Monitoring Landfast Ice Growth and Displacement

2021 ◽  
Vol 13 (11) ◽  
pp. 2168
Author(s):  
Byung-Hun Choe ◽  
Sergey Samsonov ◽  
Jungkyo Jung
Keyword(s):  
Three Dimensional ◽  
Synthetic Aperture ◽  
Ice Thickness ◽  
Water Interface ◽  
Mackenzie Delta ◽  
Sar Images ◽  
Annual Cycles ◽  
Landfast Ice ◽  
Offset Tracking ◽  
Ice Water

This study investigates the growth and displacement of landfast ice along the shoreline of the Mackenzie Delta in Northwest Territories, Canada, by synthetic aperture radar (SAR) speckle offset tracking (SPO). Three-dimensional (3D) offsets were reconstructed from Sentinel-1 ascending and descending SAR images acquired on the same dates during the November 2017–April 2018 and October 2018–May 2019 annual cycles. The analysis revealed both horizontal and vertical offsets. The annual horizontal offsets of up to ~8 m are interpreted as landfast ice displacements caused by wind and ocean currents. The annual vertical offsets of approximately −1 to −2 m were observed from landfast ice, which are likely due to longer radar penetration up to the ice–water interface with increasing landfast ice thickness. Numerical ice thickness model estimates supported the conclusion that the cumulative vertical negative offsets correspond to the growth of freshwater ice. Time-series analysis showed that the significant growth and displacement of landfast ice in the Mackenzie Delta occurred between November and January during the 2017–2018 and 2018–2019 cycles.

scholarly journals Surfaces of forced vergence disparity

2013 ◽  
Vol 72 (1) ◽  
Author(s):  
A. Rubin
Keyword(s):  
Motor System ◽  
Three Dimensional ◽  
Short Time Period ◽  
Fixation Disparity ◽  
Short Term ◽  
3 Dimensional ◽  
Time Period ◽  
Term Variation ◽  
Stimulus Distance ◽  
Short Time

Purpose: To introduce the concept of surfaces offorced vergence disparity using measurementsof fixation disparity from three young, healthy individuals.Method: Fixation disparities were measured in three individuals in relation to variation in stimulus distance and vergence demand.  All measurementswere obtained by means of the Sheedy disparometerwhich can be used to measure not only fixation disparity but also associated phorias.  For each individual, consecutive measurements of fixation disparity only were determined over a short time period at four stimulus distances (0.25 m, 0.4 m, 1 m and 2 m) and under five different vergence demands as produced with the application of different amounts of prism (either base in or base out) and also without any prism.  Parametric and non-parametric statistical methods are used to understand short-term variation of fixation disparity and pseudo-3D and stereo-pairs represent thesurfaces of forced vergence disparity with which this paper is mainly concerned.Results:  Surfaces of forced vergence disparity are very useful to study variation of fixation disparity inrelation to change in stimulus distance and vergence demand.  They are effectively 3-dimensional equivalents of 2-dimensional Ogle curves of forcedvergence disparity.Conclusion: Surfaces of forced vergence disparity may be useful in many contexts - both in relation to normal or unusual binocular behaviour.  This paper introduces such surfaces in relation to three individuals who were considered as having satisfactory binocular and accommodative-vergence function.  The surfaces assist one in understanding complicated three-dimensional or trivariate data that involves fixation disparities, different stimulus locations and different accommodative-vergence demands upon the oculo-motor system.  (S Afr Optom 2013 72(1) 25-33) 

scholarly journals Improving the Robustness of the MTI-Estimated Mining-Induced 3D Time-Series Displacements with a Logistic Model

2021 ◽  
Vol 13 (18) ◽  
pp. 3782
Author(s):  
Jiancun Shi ◽  
Zefa Yang ◽  
Lixin Wu ◽  
Siyu Qiao
Keyword(s):  
Temporal Resolution ◽  
Logistic Model ◽  
Three Dimensional ◽  
Mining Area ◽  
Synthetic Aperture ◽  
Interferometric Synthetic Aperture Radar ◽  
Prior Model ◽  
Displacement Estimation ◽  
Coal Mining Area ◽  
Surface Displacements

The previous multi-track InSAR (MTI) method can be used to retrieve mining-induced three-dimensional (3D) surface displacements with high spatial–temporal resolution by incorporating multi-track interferometric synthetic aperture radar (InSAR) observations with a prior model. However, due to the track-by-track strategy used in the previous MTI method, no redundant observations are provided to estimate 3D displacements, causing poor robustness and further degrading the accuracy of the 3D displacement estimation. This study presents an improved MTI method to significantly improve the robustness of the 3D mining displacements derived by the previous MTI method. In this new method, a fused-track strategy, instead of the previous track-by-track one, is proposed to process the multi-track InSAR measurements by introducing a logistic model. In doing so, redundant observations are generated and further incorporated into the prior model to solve 3D displacements. The improved MTI method was tested on the Datong coal mining area, China, with Sentinel-1 InSAR datasets from three tracks. The results show that the 3D mining displacements estimated by the improved MTI method had the same spatial–temporal resolution as those estimated by the previous MTI method and about 33.5% better accuracy. The more accurate 3D displacements retrieved from the improved MTI method can offer better data for scientifically understanding the mechanism of mining deformation and assessing mining-related geohazards.

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