The Experts below are selected from a list of 2205 Experts worldwide ranked by ideXlab platform
Paul Lever - One of the best experts on this subject based on the ideXlab platform.
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Real-time volume estimation of a dragline payload
2011 IEEE International Conference on Robotics and Automation, 2011Co-Authors: Alex Bewley, Rajiv Shekhar, Sam Leonard, Ben Upcroft, Paul LeverAbstract:This paper presents a method for measuring the in-bucket payload volume on a dragline excavator for the purpose of estimating the material's bulk density in real time. Knowledge of the payload's bulk density can provide feedback to mine planning and scheduling to improve blasting and therefore provide a more uniform bulk density across the Excavation Site. This allows a single optimal bucket size to be used for maximum overburden removal per dig and in turn reduce costs and emissions in dragline operation and maintenance. The proposed solution uses a range bearing laser to locate and scan full buckets between the lift and dump stages of the dragline cycle. The bucket is segmented from the scene using cluster analysis, and the pose of the bucket is calculated using the Iterative Closest Point (ICP) algorithm. Payload points are identified using a known model and subsequently converted into a height grid for volume estimation. Results from both scaled and full scale implementations show that this method can achieve an accuracy of above 95%.
Shihting Lu - One of the best experts on this subject based on the ideXlab platform.
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insights from heterogeneous structures of the 1999 mw 7 6 chi chi earthquake thrust termination in and near chushan Excavation Site central taiwan
Journal of Geophysical Research, 2016Co-Authors: Wenjeng Huang, Wenshan Chen, Chihcheng Yang, Chengshing Chiang, Shihting LuAbstract:We describe and analyze the surface and subsurface deformation of the 1999 Chi-Chi earthquake thrust termination of the Chelungpu fault in and near the Chushan Excavation Site, central Taiwan. In order to minimize damage to engineering structures within a deformation zone and formulate regulations for earthquake fault zones and fault setbacks, one needs to know the characteristics of the deformation zone and the connection between surface and subsurface deformation. The surface deformation zone of high strain induced by the earthquake faulting ranges from 15 to 70 m in width, and characterized by a 0.5 to 2 m high escarpment is much wider in the hanging wall. Exposures in the trench, 40 m long and 10 m deep, excavated across the earthquake ground rupture, show on the one hand the heterogeneous structure of a steep, monocline-like fold. On the other hand, strikingly different surface deformation profiles on either side of the 14 m wide trench, i.e., semiparabola-like and monoclinal, do not reflect in any obvious way the subsurface structure. The analysis of our detailed mapping results along with well logs suggests that the significant width variation of the surface deformation zone is attributed to secondary faults branching from the dominant fault at several tens of meters depth. The surface profile of the escarpment is controlled by the depth of the relevant fault tip, and the subsurface heterogeneous structure formed during at least four earthquakes.
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late holocene paleoseismicity of the southern part of the chelungpu fault in central taiwan evidence from the chushan Excavation Site
Bulletin of the Seismological Society of America, 2007Co-Authors: Wenshan Chen, Chihcheng Yang, Hsiaochin Yang, Huicheng Chang, Tungsheng Shih, Shihting LuAbstract:The geomorphic expression of the frontal Western Foothills in central Taiwan is usually defined by a late Holocene scarp that ranges from tens to hundreds of meters in height. This scarp is the product of displacement on a near-surface 20- 30 east-dipping thrust fault, the Chelungpu fault, which ruptured during the Chichi earthquake. The large scarp height may correspond directly to the accumulation of successive surface ruptures. The Chushan Site is located on the southern part of this fault where the Chichi earthquake produced a scarp with a 1.7-m vertical offset for the total vertical separation. Based on core-boring estimates, the vertical displace- ment on both sides is 7 m along a 24 east-dipping thrust fault. The results from our paleoseismic analysis indicate that five large paleoearthquake events have caused the large offsets during the past 2 ka. The radiocarbon age constraints of the paleoearth- quakes suggest a clustering of 540-790 cal yr B.P. (E2), 710-950 cal yr B.P. (E3), 1380-1700 cal yr B.P. (E4), 1710-1930 cal yr B.P. (E5), and the 1999 Chichi earth- quake. Events E3 and E4 have not been reported in previous studies and we did not observe event E1 (300-430 cal yr B.P.) at the Site. Based on displacement and fault segmentation from the geologic features, we argue that the two new events may have occurred along the northern part of the Chelungpu fault. The vertical slip rate is estimated to be at least 3.9 0.2 mm/yr over the past 2 ka, which is similar to the long-term estimation through a calculation of late Pleistocene-Holocene terrace el- evations on the hanging wall.
Alex Bewley - One of the best experts on this subject based on the ideXlab platform.
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Real-time volume estimation of a dragline payload
2011 IEEE International Conference on Robotics and Automation, 2011Co-Authors: Alex Bewley, Rajiv Shekhar, Sam Leonard, Ben Upcroft, Paul LeverAbstract:This paper presents a method for measuring the in-bucket payload volume on a dragline excavator for the purpose of estimating the material's bulk density in real time. Knowledge of the payload's bulk density can provide feedback to mine planning and scheduling to improve blasting and therefore provide a more uniform bulk density across the Excavation Site. This allows a single optimal bucket size to be used for maximum overburden removal per dig and in turn reduce costs and emissions in dragline operation and maintenance. The proposed solution uses a range bearing laser to locate and scan full buckets between the lift and dump stages of the dragline cycle. The bucket is segmented from the scene using cluster analysis, and the pose of the bucket is calculated using the Iterative Closest Point (ICP) algorithm. Payload points are identified using a known model and subsequently converted into a height grid for volume estimation. Results from both scaled and full scale implementations show that this method can achieve an accuracy of above 95%.
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ICRA - Real-time volume estimation of a dragline payload
2011 IEEE International Conference on Robotics and Automation, 2011Co-Authors: Alex Bewley, Rajiv Shekhar, Sam Leonard, Ben Upcroft, Paul J. A. LeverAbstract:This paper presents a method for measuring the in-bucket payload volume on a dragline excavator for the purpose of estimating the material's bulk density in real-time. Knowledge of the payload's bulk density can provide feedback to mine planning and scheduling to improve blasting and therefore provide a more uniform bulk density across the Excavation Site. This allows a single optimal bucket size to be used for maximum overburden removal per dig and in turn reduce costs and emissions in dragline operation and maintenance. The proposed solution uses a range bearing laser to locate and scan full buckets between the lift and dump stages of the dragline cycle. The bucket is segmented from the scene using cluster analysis, and the pose of the bucket is calculated using the Iterative Closest Point (ICP) algorithm. Payload points are identified using a known model and subsequently converted into a height grid for volume estimation. Results from both scaled and full scale implementations show that this method can achieve an accuracy of above 95%.
Alamin Mansouri - One of the best experts on this subject based on the ideXlab platform.
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Computer vision-based approach for rite decryption in old societies
2017Co-Authors: Jilliam María Diaz Barros, Adlane Habed, Cédric Demonceaux, Alamin MansouriAbstract:This paper presents an approach to determine the spatial arrangement of bones of horses in an Excavation Site and perform the 3D reconstruction of the scene. The relative 3D positioning of the bones was computed exploiting the information in images acquired at different levels, and used to relocate provided 3D models of the bones. A novel semi-supervised approach was proposed to generate dense point clouds of the bones from sparse features. The point clouds were later matched with the given models using Iterative Closest Point (ICP).
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MVA - Computer vision-based approach for rite decryption in old societies
2015 14th IAPR International Conference on Machine Vision Applications (MVA), 2015Co-Authors: Jilliam Maria Diaz Barros, Cédric Demonceaux, Adlane Habed, Alamin MansouriAbstract:This paper presents an approach to determine the spatial arrangement of bones of horses in an Excavation Site and perform the 3D reconstruction of the scene. The relative 3D positioning of the bones was computed exploiting the information in images acquired at different levels, and used to relocate provided 3D models of the bones. A novel semi-supervised approach was proposed to generate dense point clouds of the bones from sparse features. The point clouds were later matched with the given models using Iterative Closest Point (ICP).
Frank Bauer - One of the best experts on this subject based on the ideXlab platform.
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Low-Cost Real-Time 3D Reconstruction of Large-Scale Excavation Sites
ACM Journal on Computing and Cultural Heritage, 2016Co-Authors: Michael Zollhöfer, Christian Siegl, Mark Vetter, Boris Dreyer, Marc Stamminger, Serdar Aybek, Frank BauerAbstract:The 3D reconstruction of archeological Sites is still an expensive and time-consuming task. In this article, we present a novel interactive, low-cost approach to 3D reconstruction and compare it to a standard photogrammetry pipeline based on high-resolution photographs. Our novel real-time reconstruction pipeline is based on a low-cost, consumer-level hand-held RGB-D sensor. While scanning, the user sees a live view of the current reconstruction, allowing the user to intervene immediately and adapt the sensor path to the current scanning result. After a raw reconstruction has been acquired, the digital model is interactively warped to fit a geo-referenced map using a handle-based deformation paradigm. Even large Sites can be scanned within a few minutes, and no costly postprocessing is required. The quality of the acquired digitized raw 3D models is evaluated by comparing them to actual imagery, a geo-referenced map of the Excavation Site, and a photogrammetry-based reconstruction. We made extensive tests under real-world conditions on an archeological Excavation in Metropolis, Ionia, Turkey. We found that the reconstruction quality of our approach is comparable to that of photogrammetry. Yet, both approaches have advantages and shortcomings in specific setups, which we analyze and discuss.
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GCH - Low-cost real-time 3D reconstruction of large-scale Excavation Sites using an RGB-D camera
2014Co-Authors: Michael Zollhöfer, Christian Siegl, Mark Vetter, Boris Dreyer, Marc Stamminger, B. Riffelmacher, Frank BauerAbstract:In this paper, we present an end-to-end pipeline for the online reconstruction of large-scale outdoor environments and tightly confined indoor spaces using a low-cost consumer-level hand-held RGB-D sensor. While scanning, the user sees a live view of the current reconstruction, allowing him to intervene immediately and to adapt the sensor path to the current scanning result. After a raw reconstruction has been acquired, we interactively warp the digital model to fit a geo-referenced map using a handle based deformation paradigm. Even large Sites can be scanned within a few minutes, and no costly postprocessing is required. We developed our prototype in cooperation with researchers from the field of ancient history and geography and extensively tested the system under real world conditions on an archeological Excavation in Metropolis, Ionia, Turkey. The quality of the acquired digitized raw 3D models is evaluated by comparing them to actual imagery and a geo-referenced map of the Excavation Site. Our reconstructions can be used to take virtual measurements that are often required in research and are the basis for a digital preservation of our cultural heritage. In addition, digital models are a helpful tool for teaching as well as for edutainment purposes making such information accessible to the general public.
