Computed tomography(CT)can inspect the internal structure of concrete with high resolution,but improving the accuracy of measurements remains a key challenge due to the reliance on complex image processing and signifi...Computed tomography(CT)can inspect the internal structure of concrete with high resolution,but improving the accuracy of measurements remains a key challenge due to the reliance on complex image processing and significant manual intervention.This study aims to optimize CT scanning parameters to enhance the accuracy of measuring crack widths and rebar volumes in reinforced concrete.Nine sets of specimens,each with varying rebar diameters and concrete cover thicknesses,were scanned before and after corrosion using an Optima CT scanner,followed by three-dimensional reconstructions using Avizo software.The effects of threshold values and“Erosion”coefficients on measurement accuracy were evaluated.The results demonstrated that an optimal lower threshold of 2950,combined with an‘Erosion’coefficient of 6,effectively limits the measurement error of rebar volumes to within 1%.The optimal threshold for measuring crack widths was influenced by the crack width,rebar diameter,and concrete cover thickness.Additionally,an optimized formula for determining crack measurement thresholds was proposed.This study significantly improves the accuracy of CT-based non-destructive testing(NDT)techniques,providing valuable insights for structural health monitoring(SHM).展开更多
Three-dimensional(3D)developments of land,such as complex high-rises,put enormous pressure on current land administration systems that have ad hoc approaches to 3D property management.These approaches are unable to su...Three-dimensional(3D)developments of land,such as complex high-rises,put enormous pressure on current land administration systems that have ad hoc approaches to 3D property management.These approaches are unable to support effective 3D storage,analysis and visualisation of property information.Effective visualisation is one of the essential components in realisation of a truly 3D cadastre.Currently,several 3D visualisation applications and cadastral prototypes have been developed around the world.However,they do not effectively represent ownership information in 3D because they have not been developed based on 3D cadastral visualisation requirements.After candidate 3D visualisation solutions were compared with user-derived visualisation criteria,a web-based 3D visualisation prototype was designed and developed.The functionality,usability and efficiency of the prototype were evaluated by potential users involved in the registration and management of property.While there was a high level of enthusiasm for the features of the prototype,the results also suggest further directions for development of 3D cadastral visualisation.展开更多
This paper presents research into applying virtual environment (VE) technology to supply chain management (SCM). Our research work has employed virtual manufacturing environments to represent supply chain nodes to sim...This paper presents research into applying virtual environment (VE) technology to supply chain management (SCM). Our research work has employed virtual manufacturing environments to represent supply chain nodes to simulate processes and activities in supply chain management. This will enable those who are involved in these processes and activities to gain an intuitive understanding of them, so as to design robust supply chains and make correct decisions at the right time. A framework system and its hierarchical structure for visualising and simulating supply chains in virtual environments are reported and detailed in this paper.展开更多
The starting point of this paper is the idea that a comprehensive understanding of the earth and its systems calls for consideration of bygone views of the world.Creating facsimiles of antique globes in the form of di...The starting point of this paper is the idea that a comprehensive understanding of the earth and its systems calls for consideration of bygone views of the world.Creating facsimiles of antique globes in the form of digital globes provides a new opportunity to make such bygone world views accessible to a wide scientific audience.However,up to now,little practical experience in applying digital technology on globes has been made.Considering these attempts by thorough synopsis,this article deduces a comprehensive approach on virtual representations of antique globes that can be described by the superordinate concept of virtual representation.This concept comprises facilities of data acquisition of the original globe,ways of visualising the digitised globe and its final cartographic preparation.Applications that arise from this procedure are exemplified through both virtual hyperglobes and tactile hyperglobes.New findings on a 16th century earth globe are encouraging results of the presented virtual representation approach,which may offer a sustainable visualisation platform of interdisciplinary research.展开更多
文摘Computed tomography(CT)can inspect the internal structure of concrete with high resolution,but improving the accuracy of measurements remains a key challenge due to the reliance on complex image processing and significant manual intervention.This study aims to optimize CT scanning parameters to enhance the accuracy of measuring crack widths and rebar volumes in reinforced concrete.Nine sets of specimens,each with varying rebar diameters and concrete cover thicknesses,were scanned before and after corrosion using an Optima CT scanner,followed by three-dimensional reconstructions using Avizo software.The effects of threshold values and“Erosion”coefficients on measurement accuracy were evaluated.The results demonstrated that an optimal lower threshold of 2950,combined with an‘Erosion’coefficient of 6,effectively limits the measurement error of rebar volumes to within 1%.The optimal threshold for measuring crack widths was influenced by the crack width,rebar diameter,and concrete cover thickness.Additionally,an optimized formula for determining crack measurement thresholds was proposed.This study significantly improves the accuracy of CT-based non-destructive testing(NDT)techniques,providing valuable insights for structural health monitoring(SHM).
文摘Three-dimensional(3D)developments of land,such as complex high-rises,put enormous pressure on current land administration systems that have ad hoc approaches to 3D property management.These approaches are unable to support effective 3D storage,analysis and visualisation of property information.Effective visualisation is one of the essential components in realisation of a truly 3D cadastre.Currently,several 3D visualisation applications and cadastral prototypes have been developed around the world.However,they do not effectively represent ownership information in 3D because they have not been developed based on 3D cadastral visualisation requirements.After candidate 3D visualisation solutions were compared with user-derived visualisation criteria,a web-based 3D visualisation prototype was designed and developed.The functionality,usability and efficiency of the prototype were evaluated by potential users involved in the registration and management of property.While there was a high level of enthusiasm for the features of the prototype,the results also suggest further directions for development of 3D cadastral visualisation.
基金This work is partially sponsored by the Cheung Kong Scholars Programme of the People's Republic of China.
文摘This paper presents research into applying virtual environment (VE) technology to supply chain management (SCM). Our research work has employed virtual manufacturing environments to represent supply chain nodes to simulate processes and activities in supply chain management. This will enable those who are involved in these processes and activities to gain an intuitive understanding of them, so as to design robust supply chains and make correct decisions at the right time. A framework system and its hierarchical structure for visualising and simulating supply chains in virtual environments are reported and detailed in this paper.
文摘The starting point of this paper is the idea that a comprehensive understanding of the earth and its systems calls for consideration of bygone views of the world.Creating facsimiles of antique globes in the form of digital globes provides a new opportunity to make such bygone world views accessible to a wide scientific audience.However,up to now,little practical experience in applying digital technology on globes has been made.Considering these attempts by thorough synopsis,this article deduces a comprehensive approach on virtual representations of antique globes that can be described by the superordinate concept of virtual representation.This concept comprises facilities of data acquisition of the original globe,ways of visualising the digitised globe and its final cartographic preparation.Applications that arise from this procedure are exemplified through both virtual hyperglobes and tactile hyperglobes.New findings on a 16th century earth globe are encouraging results of the presented virtual representation approach,which may offer a sustainable visualisation platform of interdisciplinary research.
