scholarly journals A Hierarchical Multi-Temporal InSAR Method for Increasing the Spatial Density of Deformation Measurements

2014 ◽  
Vol 6 (4) ◽  
pp. 3349-3368 ◽  
Author(s):  
Tao Li ◽  
Guoxiang Liu ◽  
Hui Lin ◽  
Hongguo Jia ◽  
Rui Zhang ◽  
...  
Keyword(s):  
Spatial Density ◽  
Multi Temporal ◽  
Deformation Measurements

scholarly journals Identify and Monitor Growth Faulting Using InSAR over Northern Greater Houston, Texas, USA

2019 ◽  
Vol 11 (12) ◽  
pp. 1498 ◽  
Author(s):  
Feifei Qu ◽  
Zhong Lu ◽  
Jin-Woo Kim ◽  
Weiyu Zheng
Keyword(s):  
Active Faults ◽  
Slip Rate ◽  
Local Deformation ◽  
Spatial Density ◽  
Causal Mechanism ◽  
Montgomery County ◽  
Groundwater Exploitation ◽  
Long Time ◽  
Multi Temporal ◽  
Continuous Mining

Growth faults are widely distributed in the Greater Houston (GH) region of Texas, USA, and the existence of faulting could interrupt groundwater flow and aggravate local deformation. Faulting-induced property damages have become more pronounced over the last few years, necessitating further investigation of these faults. Interferometric synthetic aperture radar (InSAR) has been proved to be an effective way for mapping deformations along and/or across fault traces. However, extracting short-wavelength small-amplitude creep signal (about 10–20 mm/yr) from long time span interferograms is extremely difficult, especially in agricultural or vegetated areas. This study aims to position, map and monitor the rate, extent, and temporal evolution of faulting over GH at the highest spatial density using Multi-temporal InSAR (MTI) technique. The MTI method, which maximizes usable signal and correlation, has the ability to identify and monitor faulting and provide accurate and detailed depiction of active faults. Two neighboring L-band Advanced Land Observing (ALOS) tracks (2007–2011) are utilized in this research. Numerous areas of sharp phase discontinuities have been discerned from MTI-derived velocity map. InSAR measurements allow us to position both previously known faults traces as well as nucleation of new fractures not previously revealed by other ground/space techniques. Faulting damages and surface scarps were evident at most InSAR-mapped fault locations through our site investigations. The newly discovered fault activation appears to be related to excessive groundwater exploitation from the Jasper aquifer in Montgomery County. The continuous mining of groundwater from the Jasper aquifer formed new water-level decline cones over Montgomery County, corroborating the intensity of new fractures. Finally, we elaborate the localized fault activities and evaluate the characteristics of faulting (locking depth and slip rate) through modeling MTI-derived deformation maps. The SW–NE-oriented faults pertain to normal faulting with an average slip rate of 7–13 mm/yr at a shallow locking depth of less than 4 km. Identifying and characterizing active faults through MTI and deformation modeling can provide insights into faulting, its causal mechanism and potential damages to infrastructure over the GH.

scholarly journals Integrated Geophysics and Geomatics Surveys in the Valley of the Kings

Sensors ◽  
2020 ◽  
Vol 20 (6) ◽  
pp. 1552 ◽  
Author(s):  
Francesco Porcelli ◽  
Luigi Sambuelli ◽  
Cesare Comina ◽  
Antonia Spanò ◽  
Andrea Lingua ◽  
...  
Keyword(s):  
Laser Scanning ◽  
Large Scale ◽  
Spatial Density ◽  
3D Mapping ◽  
Archaeological Heritage ◽  
Geophysical Surveys ◽  
Multi Temporal ◽  
Close Range ◽  
Ground Penetrating ◽  
Invasive Techniques

Recent results within the framework of the collaborative project The Complete Geophysical Survey of the Valley of the Kings (VOK) (Luxor, Egypt) are reported in this article. In October 2018, a team of geomatics and geophysics researchers coordinated by the Polytechnic University of Turin worked side by side in the VOK. Topographic measurements in support of geophysical surveys and the achievement of a very large-scale 3D map of the Eastern VOK were the two main objectives of the geomatics campaign. Innovative 3D metric technologies and methods, based on terrestrial laser scanning (both static and mobile) and close-range photogrammetry were employed by the Geomatics team. The geophysical campaign focused on the acquisition of Electrical Resistivity Tomography (ERT), Ground Penetrating Radar (GPR) and high spatial density Geomagnetic (GM) data. ERT new data around KV62, both inverted in 2D sections and added to the previous ones to perform a new global 3D inversion, confirm the previous results showing both conductive and resistive anomalies that have to be explained. GPR timeslices showed some interesting features in the area in front of the KV2 entrance where GM gradient map also presents localized anomalies. In the area SSW of the KV2 the GM gradient maps evidenced also a large semicircular anomaly which, up to now, has no explanation. The potentialities of using magnetic techniques as a complement to other non-invasive techniques in the search for structures of archeological significance have been explored. The application of modern and innovative methods of 3D metric survey enabled to achieve a complete 3D mapping of what is currently visible in the valley. The integration of 2D/3D mapping data concerning visible elements and hypothetical anomalies, together with the recovering in the same global reference system of underground documentation pertaining to the Theban Mapping Project, prefigure the enhancement of multi-temporal site representation. This strategy enables the fruition development of the already discovered archaeological heritage, using modern criteria of valorization and conservation.

scholarly journals INTEGRATING MULTI-TEMPORAL SAR IMAGES AND GPS DATA TO MONITOR THREE-DIMENSIONAL LAND SUBSIDENCE

2019 ◽  
Vol IV-3/W1 ◽  
pp. 9-16
Author(s):  
H. Ito ◽  
J. Susaki ◽  
T. Anahara
Keyword(s):  
Land Subsidence ◽  
Least Squares Method ◽  
Effective Means ◽  
Three Dimensional ◽  
Persistent Scatterer Interferometry ◽  
Sar Images ◽  
Persistent Scatterer ◽  
Multi Temporal ◽  
Interferometric Sar ◽  
Deformation Measurements

<p><strong>Abstract.</strong> Synthetic aperture radar (SAR) is an effective means of monitoring land subsidence, and differential interferometric SAR (DInSAR) is commonly used to acquire the necessary data. In particular, persistent scatterer interferometry (PSI) can be used to measure land subsidence accurately over a wide area from multi-temporal SAR images. However, the estimated displacement is obtained only in the radar line-of-sight (LOS) direction, making it necessary to develop a method for measuring three-dimensional displacements by combining multidirectional observations. Therefore, we propose herein a method for estimating three-dimensional displacement velocities by combining the results from PSI and geodetic deformation measurements, namely, Global Positioning System and leveling data. We apply the least-squares method to Kansai International Airport in Japan by using 13 ALOS-2/PALSAR-2 ascending images from 2014 to 2018 and 17 ALOS-2/PALSAR-2 descending images from 2015 to 2018. In validation, the rootmean- square errors are 14, 16, and 14 mm/year for the east–west, north–south, and vertical components, respectively, showing that combining PSI results and geodetic deformation measurements is effective for monitoring land subsidence.</p>

Reconstruction of Objects from their Projections Using Orthogonal Functions

1973 ◽  
Vol 31 ◽  
pp. 268-269
Author(s):  
Elrnar Zeitler
Keyword(s):  
Unit Area ◽  
Three Dimensional ◽  
One Dimension ◽  
Spatial Density ◽  
Dimensional Representation ◽  
Orthogonal Functions ◽  
Object A ◽  
Plane Normal ◽  
Dimensional Object ◽  
Spatial Density Distribution

Considering any finite three-dimensional object, a “projection” is here defined as a two-dimensional representation of the object's mass per unit area on a plane normal to a given projection axis, here taken as they-axis. Since the object can be seen as being built from parallel, thin slices, the relation between object structure and its projection can be reduced by one dimension. It is assumed that an electron microscope equipped with a tilting stage records the projectionWhere the object has a spatial density distribution p(r,ϕ) within a limiting radius taken to be unity, and the stage is tilted by an angle 9 with respect to the x-axis of the recording plane.

The Relationship Between Leader–Member Exchange and Employees’ Proactive Behaviors

2019 ◽  
Vol 18 (2) ◽  
pp. 106-111
Author(s):  
Fong-Yi Lai ◽  
Szu-Chi Lu ◽  
Cheng-Chen Lin ◽  
Yu-Chin Lee
Keyword(s):  
Hierarchical Linear Modeling ◽  
Future Research ◽  
Leader Member Exchange ◽  
Voice Behavior ◽  
Linear Modeling ◽  
Team Members ◽  
Member Exchange ◽  
Multi Temporal ◽  
The Relationship ◽  
Practical Implications

Abstract. The present study proposed that, unlike prior leader–member exchange (LMX) research which often implicitly assumed that each leader develops equal-quality relationships with their supervisors (leader’s LMX; LLX), every leader develops different relationships with their supervisors and, in turn, receive different amounts of resources. Moreover, these differentiated relationships with superiors will influence how leader–member relationship quality affects team members’ voice and creativity. We adopted a multi-temporal (three wave) and multi-source (leaders and employees) research design. Hypotheses were tested on a sample of 227 bank employees working in 52 departments. Results of the hierarchical linear modeling (HLM) analysis showed that LLX moderates the relationship between LMX and team members’ voice behavior and creative performance. Strengths, limitations, practical implications, and directions for future research are discussed.

Deformation Measurements by Echocardiography versus Late Enhancement Magnetic Resonance Imaging in Patients with Coronary Artery Disease

2012 ◽  
Vol 8 (2) ◽  
pp. 101
Author(s):  
Brage H Amundsen ◽  
Anders Thorstensen ◽  
Asbjørn Støylen ◽  
◽  
◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Coronary Artery Disease ◽  
Coronary Artery ◽  
Magnetic Resonance ◽  
Late Enhancement ◽  
High Temporal Resolution ◽  
Resonance Imaging ◽  
Deformation Imaging ◽  
Artery Disease ◽  
Deformation Measurements

The aim of this article is to discuss the present and future potential of deformation imaging by echocardiography and scar visualisation by magnetic resonance imaging (MRI) in patients with coronary artery disease (CAD). The two methods are clearly different: one is concerned with function, the other with morphology. Echocardiography, with its versatility of methods and high applicability, will continue to be the workhorse in cardiac imaging of patients with CAD. Important additional information can be extracted from deformation imaging methods, especially due to the high temporal resolution in tissue Doppler. Deformation measurements in 3D images are still limited by their lower resolution compared with 2D but will continue to improve. The standardisation of image analysis and the collaboration within the echocardiographic community to conduct larger studies will be important tasks in the attempt to establish evidence for the new methods. Late enhancement MRI is a method with unique properties and will continue to be an important alternative in selected patients and settings, as well as an invaluable research tool.

Fabrication of Nanoscale Hydrophobic Regions on Anodic Alumina for Selective Adhesion of Biologic Molecules

2003 ◽  
Vol 773 ◽  
Author(s):  
Xiefan Lin ◽  
Anthony S. W. Ham ◽  
Natalie A. Villani ◽  
Whye-Kei Lye ◽  
Qiyu Huang ◽  
...  
Keyword(s):  
Anodic Alumina ◽  
Biological Molecules ◽  
Spatial Density ◽  
Length Scale ◽  
Adhesion Sites ◽  
A Cell ◽  
Adhesive Molecules ◽  
Receptor Clusters ◽  
Molecular Bonding ◽  
Fabrication Parameters

AbstractStudies of selective adhesion of biological molecules provide a path for understanding fundamental cellular properties. A useful technique is to use patterned substrates, where the pattern of interest has the same length scale as the molecular bonding sites of a cell, in the tens of nanometer range. We employ electrochemical methods to grow anodic alumina, which has a naturally ordered pore structure (interpore spacing of 40 to 400 nm) controlled by the anodization potential. We have also developed methods to selectively fill the alumina pores with materials with contrasting properties. Gold, for example, is electrochemically plated into the pores, and the excess material is removed by backsputter etching. The result is a patterned surface with closely separated islands of Au, surrounded by hydrophilic alumina. The pore spacing, which is determined by fabrication parameters, is hypothesized to have a direct effect on the spatial density of adhesion sites. By attaching adhesive molecules to the Au islands, we are able to observe and study cell rolling and adhesion phenomena. Through the measurements it is possible to estimate the length scale of receptor clusters on the cell surface. This information is useful in understanding mechanisms of leukocytes adhesion to endothelial cells as well as the effect of adhesion molecules adaptation on transmission of extracellular forces. The method also has applications in tissue engineering, drug and gene delivery, cell signaling and biocompatibility design.

An Optoelectronic System for Real-Time Surface Deformation Measurements

Vestnik MEI ◽  
2019 ◽  
Vol 2 (2) ◽  
pp. 101-108
Author(s):  
Anton Yu. Poroykov ◽  
◽  
Konstantin M. Lapitskiy ◽  
Keyword(s):  
Real Time ◽  
Surface Deformation ◽  
Optoelectronic System ◽  
Deformation Measurements
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