Current developments in 3D printing （3DP） technology provide the opportunity to produce rock-like specimens and geotechnical models through additive man- ufacturing, that is, from a file viewed with a computer to a ...Current developments in 3D printing （3DP） technology provide the opportunity to produce rock-like specimens and geotechnical models through additive man- ufacturing, that is, from a file viewed with a computer to a real object. This study investigated the serviceability of 3DP products as substitutes for rock specimens and rock-type materials in experimental analysis of deformation and failure in the laboratory. These experiments were performed on two types of materials as follows： （1） compressive experiments on printed sand-powder specimens in different shapes and structures, including intact cylinders, cylinders with small holes, and cuboids with pre-existing cracks, and （2） com- pressive and shearing experiments on printed polylactic acid cylinders and molded shearing blocks. These tentative tests for 3DP technology have exposed its advantages in produc- ing complicated specimens with special external forms and internal structures, the mechanical similarity of its product to rock-type material in terms of deformation and failure, and its precision in mapping shapes from the original body to the trial sample （such as a natural rock joint）. These experiments and analyses also successfully demonstrate the potential and prospects of 3DP technology to assist in the deformation and failure analysis of rock-type materials, as well as in the sim- ulation of similar material modeling experiments.展开更多
Flood visualization is an effective and intuitive tool for representing flood information from abstract spatiotemporal data.With the growing demand for flood disaster visualizations and mitigation,augmented flood visu...Flood visualization is an effective and intuitive tool for representing flood information from abstract spatiotemporal data.With the growing demand for flood disaster visualizations and mitigation,augmented flood visualizations that support decision makers’perspectives are needed,which can be enhanced by emerging augmented reality(AR)and 3D printing technologies.This paper proposes an innovative flood AR visualization method based on a 3D-printed terrain model and investigates essential techniques,such as the suitable size calculation of the terrain models,the adaptive processing of flood data,and hybridizing virtual flood and terrain models.A prototype experimental system(PES)based on the proposed method and a comparison experimental system(CES)based on a virtual terrain are developed to conduct comparative experiments,which combine the system performance and questionnaire method to evaluate the efficiency and usability of the proposed method.The statistical results indicate that the method is useful for assisting participants in understanding the flood hazard and providing a more intuitive and realistic visual experience compared with that of the traditional AR flood visualization method.The frame rate is stable at 60 frames per second(FPS),which means that the proposed method is more efficient than the traditional AR flood visualization method.展开更多
Three-dimensional(3D)printing has evolved to incorporate controlled delivery systems to guide the regeneration of complex tissues,with limited clinical translation.The challenges include the limited precision in spati...Three-dimensional(3D)printing has evolved to incorporate controlled delivery systems to guide the regeneration of complex tissues,with limited clinical translation.The challenges include the limited precision in spatiotemporal delivery and poorly understood in vivo scaffold degradation rates.Here,we report auspicious preclinical outcomes in the functional regeneration of temporomandibular joint(TMJ)discs of mini-pigs.TMJ disc has been an extremely challenging target for regenerative engineering given the uniquely heterogeneous matrix distribution and region-variant anisotropic orientation.We optimally implemented advanced 3D printing technologies with micro-precise spatiotemporal delivery to build anatomically correct,bioactive scaffolds with native-like regionally variant microstructure and mechanical properties.We also applied quantum dots(QDs)labeling of scaffolds to enable non-invasive in vivo degradation tracking.In mini-pigs,the scaffold implantation upon discectomy has successfully led to in-situ regeneration of TMJ discs by 3 months,exhibiting native-like heterogeneity and multi-scale mechanical properties without any sign of cartilage damage.In addition,our non-invasive imaging resulted in reliable in vivo tracking of scaffold degradation,exhibiting notably different degradation rates between individual animals.Our findings suggest a significant translational potential of our cell-free,bioactive scaffolds equipped with non-invasive tracking modality for in-situ tissue engineering of TMJ discs.展开更多
基金financial support from the National Natural Science Foundation of China (Grants 41172284 and 51379202)
文摘Current developments in 3D printing （3DP） technology provide the opportunity to produce rock-like specimens and geotechnical models through additive man- ufacturing, that is, from a file viewed with a computer to a real object. This study investigated the serviceability of 3DP products as substitutes for rock specimens and rock-type materials in experimental analysis of deformation and failure in the laboratory. These experiments were performed on two types of materials as follows： （1） compressive experiments on printed sand-powder specimens in different shapes and structures, including intact cylinders, cylinders with small holes, and cuboids with pre-existing cracks, and （2） com- pressive and shearing experiments on printed polylactic acid cylinders and molded shearing blocks. These tentative tests for 3DP technology have exposed its advantages in produc- ing complicated specimens with special external forms and internal structures, the mechanical similarity of its product to rock-type material in terms of deformation and failure, and its precision in mapping shapes from the original body to the trial sample （such as a natural rock joint）. These experiments and analyses also successfully demonstrate the potential and prospects of 3DP technology to assist in the deformation and failure analysis of rock-type materials, as well as in the sim- ulation of similar material modeling experiments.
基金the National Key R&D Plan of China[grant number 2017YFC1500906]the National Natural Science Foundation of China[grant number 41871323,41771442]+1 种基金Pre-research Project of Equipment Development Department[grant number 315050501]the Zhejiang Institute of Advanced Technology Chinese Academy of Sciences Special Fund Collaborative Innovation Project[grant number ZK-CX-2018-04].
文摘Flood visualization is an effective and intuitive tool for representing flood information from abstract spatiotemporal data.With the growing demand for flood disaster visualizations and mitigation,augmented flood visualizations that support decision makers’perspectives are needed,which can be enhanced by emerging augmented reality(AR)and 3D printing technologies.This paper proposes an innovative flood AR visualization method based on a 3D-printed terrain model and investigates essential techniques,such as the suitable size calculation of the terrain models,the adaptive processing of flood data,and hybridizing virtual flood and terrain models.A prototype experimental system(PES)based on the proposed method and a comparison experimental system(CES)based on a virtual terrain are developed to conduct comparative experiments,which combine the system performance and questionnaire method to evaluate the efficiency and usability of the proposed method.The statistical results indicate that the method is useful for assisting participants in understanding the flood hazard and providing a more intuitive and realistic visual experience compared with that of the traditional AR flood visualization method.The frame rate is stable at 60 frames per second(FPS),which means that the proposed method is more efficient than the traditional AR flood visualization method.
基金National Institute of Health grant NIH 5R01DE029321(C.H.L.)。
文摘Three-dimensional(3D)printing has evolved to incorporate controlled delivery systems to guide the regeneration of complex tissues,with limited clinical translation.The challenges include the limited precision in spatiotemporal delivery and poorly understood in vivo scaffold degradation rates.Here,we report auspicious preclinical outcomes in the functional regeneration of temporomandibular joint(TMJ)discs of mini-pigs.TMJ disc has been an extremely challenging target for regenerative engineering given the uniquely heterogeneous matrix distribution and region-variant anisotropic orientation.We optimally implemented advanced 3D printing technologies with micro-precise spatiotemporal delivery to build anatomically correct,bioactive scaffolds with native-like regionally variant microstructure and mechanical properties.We also applied quantum dots(QDs)labeling of scaffolds to enable non-invasive in vivo degradation tracking.In mini-pigs,the scaffold implantation upon discectomy has successfully led to in-situ regeneration of TMJ discs by 3 months,exhibiting native-like heterogeneity and multi-scale mechanical properties without any sign of cartilage damage.In addition,our non-invasive imaging resulted in reliable in vivo tracking of scaffold degradation,exhibiting notably different degradation rates between individual animals.Our findings suggest a significant translational potential of our cell-free,bioactive scaffolds equipped with non-invasive tracking modality for in-situ tissue engineering of TMJ discs.
