Recent interior carving methods for functional design necessitate a cumbersome cut-and-glue process in fabrication.Wepropose a method to generate interior voids which not only satisfy the functional purposes but are a...Recent interior carving methods for functional design necessitate a cumbersome cut-and-glue process in fabrication.Wepropose a method to generate interior voids which not only satisfy the functional purposes but are also support-free during the 3D printing process.We introduce a support-free unit structure for voxelization and derive the wall thicknesses parametrization for continuous optimization.Wealso design a discrete dithering algorithm to ensure the printability of ghost voxels.The interior voids are iteratively carved by alternating the optimization and dithering.We apply our method to optimize the static and rotational stability,and print various results to evaluate the efficacy.展开更多
The ubiquitous spatiotemporal information extracted from Internet texts limits its application in spatiotemporal association and analysis due to its unstructured nature and uncertainty.This study uses ST-Voxel modelin...The ubiquitous spatiotemporal information extracted from Internet texts limits its application in spatiotemporal association and analysis due to its unstructured nature and uncertainty.This study uses ST-Voxel modeling to solve the problem of structured modeling and the association of ubiquitous spatiotemporal information in natural language texts.It provides a new solution for associating ubiquitous spatiotemporal information on the Internet and discovering public opinion.The main contributions of this paper include:(1)It proposes a convolved method for ST-Voxel,which solves the voxel modeling problem of unstructured and uncertain spatiotemporal objects and spatiotemporal relation in natural language texts.Experiments show that this method can effectively model 5 types of spatiotemporal objects and 16 types of uncertain spatiotemporal relation founded in texts;(2)It realizes the unknown event discovery based on voxelized spatiotemporal information association.Experiments show that this method can effectively solve the aggregation of ubiquitous spatiotemporal information in multi-natural language texts,which is conducive to discovering spatiotemporal events.The selection of convolution parameters in voxel modeling is also discussed.A parameter selection method for balancing the discovery capability and discovery accuracy of spatiotemporal events is given.展开更多
Recent advancements in computing research and technology will allow future immersive virtual reality systems to be voxel-based, i.e. entirely based on gap-less, spatial representations of volumetric pixels. The curren...Recent advancements in computing research and technology will allow future immersive virtual reality systems to be voxel-based, i.e. entirely based on gap-less, spatial representations of volumetric pixels. The current popularity of pixel-based videoconferencing systems could turn into true telepresence experiences that are voxel-based. Richer, non-verbal communication will be possible thanks to the three-dimensional nature of such systems. An effective telepresence experience is based on the users’ sense of copresence with others in the virtual environment and on a sense of embodiment. We investigate two main quality of service factors, namely voxel size and network latency, to identify acceptable threshold values for maintaining the copresence and embodiment experience. We present a working prototype implementation of a voxel-based telepresence system and can show that even a coarse 64 mm voxel size and an overall round-trip latency of 542 ms are sufficient to maintain copresence and embodiment experiences. We provide threshold values for noticeable, disruptive, and unbearable latencies that can serve as guidelines for future voxel and other telepresence systems.展开更多
This paper presents a new method for extract three-dimensional （3D） discrete spherical Fourier descriptors based on surface curvature voxels for pollen particle recognition. In order to reduce the high amount of pol...This paper presents a new method for extract three-dimensional （3D） discrete spherical Fourier descriptors based on surface curvature voxels for pollen particle recognition. In order to reduce the high amount of pollen information and noise disturbance, the geometric normalized curvature voxels with the principal curvedness are first extracted to represent the intrinsic pollen volumetric data. Then the curvature voxels are decomposed into radial and angular components with spherical harmonic transform in spherical coordinates. Finally the 3D discrete Fourier transform is applied to the decomposed curvature voxels to obtain the 3D spherical Fourier descriptors for pollen recognition. Experimental results show that the presented descriptors are invariant to different pollen particle geometric transformations, such as pose change and spatial rotation, and can obtain high recognition accuracy and speed simultaneously.展开更多
文摘Recent interior carving methods for functional design necessitate a cumbersome cut-and-glue process in fabrication.Wepropose a method to generate interior voids which not only satisfy the functional purposes but are also support-free during the 3D printing process.We introduce a support-free unit structure for voxelization and derive the wall thicknesses parametrization for continuous optimization.Wealso design a discrete dithering algorithm to ensure the printability of ghost voxels.The interior voids are iteratively carved by alternating the optimization and dithering.We apply our method to optimize the static and rotational stability,and print various results to evaluate the efficacy.
基金supported by The Excellent Youth Foundation of Henan Municipal Natural Science Foundation(212300410096)Program of Song Shan Laboratory(Included in the Management of Major Science and Technology Program of Henan Province)under Grant number 221100211000-03The National Key R&D Plan of China(2018YFB0505304).
文摘The ubiquitous spatiotemporal information extracted from Internet texts limits its application in spatiotemporal association and analysis due to its unstructured nature and uncertainty.This study uses ST-Voxel modeling to solve the problem of structured modeling and the association of ubiquitous spatiotemporal information in natural language texts.It provides a new solution for associating ubiquitous spatiotemporal information on the Internet and discovering public opinion.The main contributions of this paper include:(1)It proposes a convolved method for ST-Voxel,which solves the voxel modeling problem of unstructured and uncertain spatiotemporal objects and spatiotemporal relation in natural language texts.Experiments show that this method can effectively model 5 types of spatiotemporal objects and 16 types of uncertain spatiotemporal relation founded in texts;(2)It realizes the unknown event discovery based on voxelized spatiotemporal information association.Experiments show that this method can effectively solve the aggregation of ubiquitous spatiotemporal information in multi-natural language texts,which is conducive to discovering spatiotemporal events.The selection of convolution parameters in voxel modeling is also discussed.A parameter selection method for balancing the discovery capability and discovery accuracy of spatiotemporal events is given.
文摘Recent advancements in computing research and technology will allow future immersive virtual reality systems to be voxel-based, i.e. entirely based on gap-less, spatial representations of volumetric pixels. The current popularity of pixel-based videoconferencing systems could turn into true telepresence experiences that are voxel-based. Richer, non-verbal communication will be possible thanks to the three-dimensional nature of such systems. An effective telepresence experience is based on the users’ sense of copresence with others in the virtual environment and on a sense of embodiment. We investigate two main quality of service factors, namely voxel size and network latency, to identify acceptable threshold values for maintaining the copresence and embodiment experience. We present a working prototype implementation of a voxel-based telepresence system and can show that even a coarse 64 mm voxel size and an overall round-trip latency of 542 ms are sufficient to maintain copresence and embodiment experiences. We provide threshold values for noticeable, disruptive, and unbearable latencies that can serve as guidelines for future voxel and other telepresence systems.
基金Project supported by the National Natural Science Foundation of China (Grant No. 60472061)the Natural Science Foundation of Jiangsu Province,China (Grant No. BK20090149)the Natural Science Foundation of Higher Education Institutions of Jiangsu Province,China (Grant No. 08KJD520019).
文摘This paper presents a new method for extract three-dimensional （3D） discrete spherical Fourier descriptors based on surface curvature voxels for pollen particle recognition. In order to reduce the high amount of pollen information and noise disturbance, the geometric normalized curvature voxels with the principal curvedness are first extracted to represent the intrinsic pollen volumetric data. Then the curvature voxels are decomposed into radial and angular components with spherical harmonic transform in spherical coordinates. Finally the 3D discrete Fourier transform is applied to the decomposed curvature voxels to obtain the 3D spherical Fourier descriptors for pollen recognition. Experimental results show that the presented descriptors are invariant to different pollen particle geometric transformations, such as pose change and spatial rotation, and can obtain high recognition accuracy and speed simultaneously.
