scholarly journals Comparison of Different Remote Sensing Methods for 3D Modeling of Small Rock Outcrops

Sensors ◽  
2020 ◽  
Vol 20 (6) ◽  
pp. 1663 ◽  
Author(s):  
Tomáš Mikita ◽  
Marie Balková ◽  
Aleš Bajer ◽  
Miloš Cibulka ◽  
Zdeněk Patočka
Keyword(s):  
Surface Reconstruction ◽  
3D Model ◽  
High Fidelity ◽  
Smartphone Applications ◽  
Rock Outcrops ◽  
Terrestrial Lidar ◽  
Surface Reconstructions ◽  
Recent Developments ◽  
Acquisition Device ◽  
Remote Sensing Methods

This paper reviews the use of modern 3D image-based and Light Detection and Ranging (LiDAR) methods of surface reconstruction techniques for high fidelity surveys of small rock outcrops to highlight their potential within structural geology and landscape protection. LiDAR and Structure from Motion (SfM) software provide useful opportunities for rock outcrops mapping and 3D model creation. The accuracy of these surface reconstructions is crucial for quantitative structural analysis. However, these technologies require either a costly data acquisition device (Terrestrial LiDAR) or specialized image processing software (SfM). Recent developments in augmented reality and smartphone technologies, such as increased processing capacity and higher resolution of cameras, may offer a simple and inexpensive alternative for 3D surface reconstruction. Therefore, the aim of the paper is to show the possibilities of using smartphone applications for model creation and to determine their accuracy for rock outcrop mapping.

CO OXIDATION ON Ag(110): SURFACE RECONSTRUCTIONS CONTRA SUBSURFACE OXYGEN

2003 ◽  
Vol 10 (01) ◽  
pp. 39-48 ◽  
Author(s):  
U. BURGHAUS ◽  
A. BÖTTCHER ◽  
H. CONRAD
Keyword(s):  
Steady State ◽  
Co Oxidation ◽  
Surface Reconstruction ◽  
Quasi Steady State ◽  
Surface Reconstructions ◽  
Subsurface Oxygen

Transient CO2 formation has been studied under "quasi-steady-state" measuring conditions by means of surface titrations. By this method the reactivity of the surface could be sampled as a function of time, thereby following the formation of the surface reconstruction induced by oxygen. The reactivity of the surface towards CO oxidation was reduced in the course of the developing surface reconstruction. A possible influence of subsurface oxygen on the CO2 formation rates can be excluded.

AUTOMATED MODEL CONSTRUCTION FOR SEISMIC DISASTER ASSESSMENT OF PIPELINE NETWORK OF LIFELINE

2013 ◽  
Vol 07 (03) ◽  
pp. 1350039 ◽  
Author(s):  
M. HORI ◽  
W. LALITH ◽  
S. TANAKA ◽  
T. ICHIMURA
Keyword(s):  
Finite Element Method ◽  
3D Model ◽  
Model Construction ◽  
Geographical Information ◽  
High Fidelity ◽  
Pipeline Network ◽  
Disaster Assessment ◽  
Analysis Models ◽  
2D Model ◽  
Seismic Disaster

This paper seeks to develop a module for automated model construction of a pipeline network using geographical information system (GIS) of lifeline, for the sake of more rational seismic disaster assessment. The module is assigned a functionality which enables to generate two types of analysis models, a simple 2D model and a 3D model with high fidelity for pipe configuration. The module is coded in an objective oriented programming, so that it is easier to be extended to generate other types of analysis models. The module is applied to actual GIS, and the configuration of the generated model is verified. As an example, numerical analysis is made for the automatically constructed models by using a commercial finite element method package, and it is shown that these models are mechanically consistent and can be used for seismic disaster assessment.

Surface Reconstruction of (123) and (111) Ge(Sn) Solid Solutions Induced by Tin Segregation

1998 ◽  
Vol 05 (01) ◽  
pp. 265-268 ◽  
Author(s):  
A. Rolland ◽  
A. Rouabah ◽  
F. Cabané
Keyword(s):  
Phase Diagram ◽  
Comparative Study ◽  
Surface Reconstruction ◽  
Solid Solutions ◽  
Surface Segregation ◽  
Fair Agreement ◽  
Kinetic Curves ◽  
Surface Reconstructions ◽  
Kinetics Of

We present a comparative study of tin segregation onto the (123) and (111) surfaces of a Ge(Sn)- 0.5 at. % bicrystal using the AES technique. Between 350°C and 450°C, the maximum segregated tin amount, about 1.25 monolayer, does not vary with the orientation of the surface or the temperature. This indicates that attractive Sn-Sn forces are involved in the segregated phase which is in fair agreement with the Ge-Sn phase diagram. The shape of the kinetic curves depends on the orientation. On the (111) surface, the formation of various structures in equilibrium with the bulk is correlated with surface reconstructions. First, Sn atoms take the place of Ge adatoms to form a 2D phase; then, Sn segregates in other superficial sites, which leads to the nucleation of denser 2D phases, such as (7 × 7) structure. On the (123) surface, Sn atoms take the place of Ge atoms in quasisubstitutional sites of the superficial layers; the kinetics of surface segregation is not sensitive to sub monolayer structures.

Dynamics of Ga Clusters on GaAs(001) Surface

2000 ◽  
Vol 648 ◽  
Author(s):  
Shiro Tsukamoto ◽  
Nobuyuki Koguchi
Keyword(s):  
Substrate Temperature ◽  
Surface Reconstruction ◽  
High Energy ◽  
Gaas Layer ◽  
Scanning Tunneling ◽  
Tunneling Microscopy ◽  
Additional Layer ◽  
Surface Reconstructions ◽  
Migration Enhanced Epitaxy ◽  
Step Flow Growth

AbstractDynamics of Ga clusters and GaAs epitaxial growth on a GaAs (001) surface were successfully observed by a system in which scanning tunneling microscopy (STM) and molecular beam epitaxy (MBE) were incorporated into one unit rather than in separate chambers. With the substrate temperature of 528°C, reflection high-energy diffraction (RHEED) patterns showed a (4×6) Ga-stabilized surface reconstruction and dynamics of steps and islands were clearly observed. The detaching and attaching of small Ga clusters might cause the change of steps and islands. It seems that the small Ga clusters migrated with the diameter of about 0.8 to 1.2 nm and around the steps and islands. These clusters could be observed only when they were detached from or attached to the steps and islands. Moreover, even under the substrate temperature of 440 oC and the As4 partial pressure of 2×10−6 torr, STM images were clearly observed. After 0.1 ML Ga was additionally supplied to the sample by migration enhanced epitaxy mode, step flow growth occurred, resulting in an additional GaAs layer grown on the B-step side. Moreover, the c(4×4) As-stabilized surface reconstruction was moderate. It seems that there is an equilibrium additional layer of As amorphous adatoms on the c(4x4) surface reconstructions.

scholarly journals 3D hydrodynamic simulations of colliding winds in V444 Cygni

1999 ◽  
Vol 193 ◽  
pp. 386-387 ◽  
Author(s):  
Julian M. Pittard ◽  
Ian R. Stevens
Keyword(s):  
3D Model ◽  
Hydrodynamic Simulations ◽  
X Ray ◽  
Recent Developments ◽  
Colliding Winds

We report on recent developments in simulating colliding wind X-ray emission, and present a 3D model of the WR binary V444 Cyg (WN5+O6) which self-consistently includes radiative driving.

scholarly journals Predicting drag on rough surfaces by transfer learning of empirical correlations

2021 ◽  
Vol 933 ◽  
Author(s):  
Sangseung Lee ◽  
Jiasheng Yang ◽  
Pourya Forooghi ◽  
Alexander Stroh ◽  
Shervin Bagheri
Keyword(s):  
Neural Networks ◽  
Transfer Learning ◽  
Rough Surfaces ◽  
High Fidelity ◽  
Empirical Correlations ◽  
Practical Applications ◽  
Learning Framework ◽  
Recent Developments ◽  
Drag Prediction ◽  
Surface Statistics

Recent developments in neural networks have shown the potential of estimating drag on irregular rough surfaces. Nevertheless, the difficulty of obtaining a large high-fidelity dataset to train neural networks is deterring their use in practical applications. In this study, we propose a transfer learning framework to model the drag on irregular rough surfaces even with a limited amount of direct numerical simulations. We show that transfer learning of empirical correlations, reported in the literature, can significantly improve the performance of neural networks for drag prediction. This is because empirical correlations include ‘approximate knowledge’ of the drag dependency in high-fidelity physics. The ‘approximate knowledge’ allows neural networks to learn the surface statistics known to affect drag more efficiently. The developed framework can be applied to applications where acquiring a large dataset is difficult but empirical correlations have been reported.

scholarly journals Brief communication: 3D reconstruction of a collapsed rock pillar from web-retrieved images and terrestrial LiDAR data – The 2005 event of the West face of the Drus (Mont-Blanc massif)

2016 ◽  
Author(s):  
Antoine Guerin ◽  
Antonio Abellán ◽  
Battista Matasci ◽  
Michel Jaboyedoff ◽  
Marc-Henri Derron ◽  
...  
Keyword(s):  
Point Cloud ◽  
3D Model ◽  
Rock Avalanche ◽  
Lidar Data ◽  
The West ◽  
Terrestrial Lidar ◽  
The Face ◽  
The Difference ◽  
Historical Photographs ◽  
Mont Blanc Massif

Abstract. In June 2005, a series of major rockfall events completely wiped out the Bonatti Pillar located in the legendary Drus West face (Mont-Blanc massif, France). Terrestrial LiDAR scans of the face were acquired after this event but no pre-event point cloud is available. Thus, in order to reconstruct the volume and the shape of the collapsed blocks, a 3D model has been built using photogrammetry (SfM) based on 30 pictures collected on the Web. All these pictures were taken between September 2003 and May 2005. We then reconstructed the shape and volume of the fallen compartment by comparing the SfM model with terrestrial LiDAR data acquired in October 2005 and November 2011. The volume is calculated to 292’680 m3 (±5 %). This result is close to the value previously assessed by Ravanel and Deline (2008) for this same rock-avalanche (265’000 ± 10’000 m3). The difference between these two estimations can be explained by the rounded shape of the volume determined by photogrammetry, which may lead to a volume overestimation. However it is not excluded that the volume calculated by Ravanel and Deline (2008) is slightly underestimated, the thickness of the blocks having been assessed manually from historical photographs.

scholarly journals Disaster Reconnaissance Using Multiple Small Unmanned Aerial Vehicles

2019 ◽  
Vol 141 (06) ◽  
pp. S7-S11
Author(s):  
Jeffrey C. Derricott ◽  
Jacob B. Willis ◽  
Cameron K. Peterson ◽  
Kevin W. Franke ◽  
John D. Hedengren
Keyword(s):  
Unmanned Aerial Vehicles ◽  
Data Storage ◽  
3D Model ◽  
3D Models ◽  
Flight Time ◽  
High Fidelity ◽  
Computational Power ◽  
Government Officials ◽  
Aerial Vehicles ◽  
Before And After

Small rotorcraft unmanned air vehicles (sUAVs) are valuable tools in solving geospatial inspection challenges. One area where this is being widely explored is disaster reconnaissance [1]. Using sUAVs to collect images provides engineers and government officials critical information about the conditions before and after a disaster [2]. This is accomplished by creating high- fidelity 3D models from the sUAV’s imagery. However, using an sUAV to perform inspections is a challenging task due to constraints on the vehicle’s flight time, computational power, and data storage capabilities [3]. The approach presented in this article illustrates a method for utilizing multiple sUAVs to inspect a disaster region and merge the separate data into a single high-resolution 3D model.

Bulk defects as domain boundaries in surface reconstructions

1991 ◽  
Vol 49 ◽  
pp. 620-621
Author(s):  
D.N. Dunn ◽  
R. Ai ◽  
T.S. Savage ◽  
L.D. Marks ◽  
K.L. Merkle
Keyword(s):  
Surface Properties ◽  
Surface Science ◽  
Surface Reconstruction ◽  
Stacking Faults ◽  
Complete Picture ◽  
Reconstruction Process ◽  
Surface Reconstructions ◽  
Reconstructed Surfaces ◽  
Domain Boundaries ◽  
Reconstructed Surface

Much of the study of reconstructed surfaces has been done with surface sensitive techniques that rarely allow the investigator to probe both the bulk and surface properties. As a result, not much has been written about the possiblity of bulk defects influencing the shape and position of domains on a reconstructed surface. With the recent advent of UHV microscopes with attendent surface science chambers connected, it has become possible to examine both the bulk and surface of a given sample and obtain a more complete picture of the surface reconstruction process. We have found in several investigations of Au (001) and Si (111) surfaces that bulk defects such as dislocations and stacking faults near the surface can act as boundaries for domains of a reconstructed surface.

3D Surface Reconstruction from Multiviews for Prosthetic Design

2012 ◽  
pp. 338-351
Author(s):  
Nasrul Humaimi Bin Mahmood
Keyword(s):  
Surface Reconstruction ◽  
3D Model ◽  
Lower Limbs ◽  
Evaluation Methodology ◽  
Prosthetic Design ◽  
Prosthetic Devices ◽  
3D Surface Reconstruction ◽  
Passive Method ◽  
3D Surface ◽  
3D Data

Existing methods that use a fringe projection technique for prosthetic designs produce good results for the trunk and lower limbs; however, the devices used for this purpose are expensive. This chapter investigates the use of an inexpensive passive method involving 3D surface reconstruction from video images taken at multiple views. The design and evaluation methodology, consisting of a number of techniques suitable for prosthetic design, is developed. The method that focuses on fitting the reference model (3D model) of an object to the target data (3D data) is presented. The 3D model is obtained by a computer program while the 3D data uses the shape-from-silhouette technique in an approximately circular motion. The modification of existing model-based reconstruction – mainly on the deformation process of vertices – is discussed, and the results of different objects show a good possibility for using a passive method in prosthetic devices. The methodology developed is shown to be useful for prosthetic designers as an alternative to manual impression during the design.

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