●AIM:To determine the teaching effects of a real-time three dimensional(3D)visualization system in the operating room for early-stage phacoemulsification training.●METHODS:A total of 10 ophthalmology residents of th...●AIM:To determine the teaching effects of a real-time three dimensional(3D)visualization system in the operating room for early-stage phacoemulsification training.●METHODS:A total of 10 ophthalmology residents of the first-year postgraduate were included.All the residents were novices to cataract surgery.Real-time cataract surgical observations were performed using a custom-built 3D visualization system.The training lasted 4wk(32h)in all.A modified International Council of Ophthalmology’s Ophthalmology Surgical Competency Assessment Rubric(ICO-OSCAR)containing 4 specific steps of cataract surgery was applied.The self-assessment(self)and expert-assessment(expert)were performed through the microsurgical attempts in the wet lab for each participant.●RESULTS:Compared with pre-training assessments(self 3.2±0.8,expert 2.5±0.6),the overall mean scores of posttraining(self 5.2±0.4,expert 4.7±0.6)were significantly improved after real-time observation training of 3D visualization system(P<0.05).Scores of 4 surgical items were significantly improved both self and expert assessment after training(P<0.05).●CONCLUSION:The 3D observation training provides novice ophthalmic residents with a better understanding of intraocular microsurgical techniques.It is a useful tool to improve teaching efficiency of surgical education.展开更多
Background Intelligent garments,a burgeoning class of wearable devices,have extensive applications in domains such as sports training and medical rehabilitation.Nonetheless,existing research in the smart wearables dom...Background Intelligent garments,a burgeoning class of wearable devices,have extensive applications in domains such as sports training and medical rehabilitation.Nonetheless,existing research in the smart wearables domain predominantly emphasizes sensor functionality and quantity,often skipping crucial aspects related to user experience and interaction.Methods To address this gap,this study introduces a novel real-time 3D interactive system based on intelligent garments.The system utilizes lightweight sensor modules to collect human motion data and introduces a dual-stream fusion network based on pulsed neural units to classify and recognize human movements,thereby achieving real-time interaction between users and sensors.Additionally,the system incorporates 3D human visualization functionality,which visualizes sensor data and recognizes human actions as 3D models in real time,providing accurate and comprehensive visual feedback to help users better understand and analyze the details and features of human motion.This system has significant potential for applications in motion detection,medical monitoring,virtual reality,and other fields.The accurate classification of human actions contributes to the development of personalized training plans and injury prevention strategies.Conclusions This study has substantial implications in the domains of intelligent garments,human motion monitoring,and digital twin visualization.The advancement of this system is expected to propel the progress of wearable technology and foster a deeper comprehension of human motion.展开更多
The conventional 2D design method of culverts separated from 3D model cannot directly visualize the process of creating and renewal process. This paper explores graphics application framework of Open GL based on MFC, ...The conventional 2D design method of culverts separated from 3D model cannot directly visualize the process of creating and renewal process. This paper explores graphics application framework of Open GL based on MFC, developing the 3D visualization system of hydraulic culvert. This system effectively integrats with building design, structural design and parametric design and image processing technology. The results can be shown by 3D visualization design.展开更多
3D stereoscopic visualization technology is coming into more and more common use in the field of entertainment,and this technology is also beginning to cut a striking figure in casting industry and scientific research...3D stereoscopic visualization technology is coming into more and more common use in the field of entertainment,and this technology is also beginning to cut a striking figure in casting industry and scientific research.The history,fundamental principle,and devices of 3D stereoscopic visualization technology are reviewed in this paper.The authors’research achievements on the 3D stereoscopic visualization technology in the modeling and simulation of the casting process are presented.This technology can be used for the observation of complex 3D solid models of castings and the simulated results of solidification processes such as temperature,fluid flow,displacement,stress strain and microstructure,as well as the predicted defects such as shrinkage/porosity,cracks,and deformation.It can also be used for other areas relating to 3D models,such as assembling of dies,cores,etc.Several cases are given to compare the illustration of simulated results by traditional images and red-blue 3D stereoscopic images.The spatial shape is observed better by the new method.The prospect of3D stereoscopic visualization in the casting aspect is discussed as well.The need for aided-viewing devices is still the most prominent problem of 3D stereoscopic visualization technology.However,3D stereoscopic visualization represents the tendency of visualization technology in the future;and as the problem is solved in the years ahead,great breakthroughs will certainly be made for its application in casting design and modeling and simulation of the casting processes.展开更多
Essentially, CesiumJS—which can be accessed through the link, http://cesiumjs.org, is an open-source JavaScript library for creating virtual globe environment in performance effective, high quality of rendering, prec...Essentially, CesiumJS—which can be accessed through the link, http://cesiumjs.org, is an open-source JavaScript library for creating virtual globe environment in performance effective, high quality of rendering, precision, and user friendly. It is a wonderful tool for 3D-themed visualizations of earth. CesiumJS has a number of data sources, but none of them supports vector tile format. This article explains how to visualize Mapbox vector tiles in a CesiumJS virtual globe environment. CartoDB/BigQuery hosts vector tiles, and a process for producing vector tiles from massive vector data using the BigQuery tiler of CartoDB has been provided.展开更多
Rock-encased-backfill(RB)structures are common in underground mining,for example in the cut-andfill and stoping methods.To understand the effects of cyclic excavation and blasting activities on the damage of these RB ...Rock-encased-backfill(RB)structures are common in underground mining,for example in the cut-andfill and stoping methods.To understand the effects of cyclic excavation and blasting activities on the damage of these RB structures,a series of triaxial stepwise-increasing-amplitude cyclic loading experiments was conducted with cylindrical RB specimens(rock on outside,backfill on inside)with different volume fractions of rock(VF=0.48,0.61,0.73,and 0.84),confining pressures(0,6,9,and 12 MPa),and cyclic loading rates(200,300,400,and 500 N/s).The damage evolution and meso-crack formation during the cyclic tests were analyzed with results from stress-strain hysteresis loops,acoustic emission events,and post-failure X-ray 3D fracture morphology.The results showed significant differences between cyclic and monotonic loadings of RB specimens,particularly with regard to the generation of shear microcracks,the development of stress memory and strain hardening,and the contact forces and associated friction that develops along the rock-backfill interface.One important finding is that as a function of the number of cycles,the elastic strain increases linearly and the dissipated energy increases exponentially.Also,compared with monotonic loading,the cyclic strain hardening characteristics are more sensitive to rising confining pressures during the initial compaction stage.Another finding is that compared with monotonic loading,more shear microcracks are generated during every reloading stage,but these microcracks tend to be dispersed and lessen the likelihood of large shear fracture formation.The transition from elastic to plastic behavior varies depending on the parameters of each test(confinement,volume fraction,and cyclic rate),and an interesting finding was that the transformation to plastic behavior is significantly lower under the conditions of 0.73 rock volume fraction,400 N/s cyclic loading rate,and 9 MPa confinement.All the findings have important practical implications on the ability of backfill to support underground excavations.展开更多
Digital holography has high potentials for future 3D imaging and display technology.We present a method for a dynamic full-color digital holographic 3D display on single digital micro-mirror device(DMD)with full-color...Digital holography has high potentials for future 3D imaging and display technology.We present a method for a dynamic full-color digital holographic 3D display on single digital micro-mirror device(DMD)with full-color,high-speed and high-fidelity characteristics.We combine the square regions of adjacent micro-mirrors into super-pixels that can modulate amplitude and phase independently.Gray images are achieved by amplitude modulation and precise positioning of each color is achieved by phase modulation.The proposed method realizes a full-color imaging based on the three primary colors and achieves measured structural similarity of more than 88%and color similarity of more than 98%,while retaining the high switch speed of 9 kHz,thus achieving dynamic full-color 3D display on charge-coupled device(CCD).展开更多
Understanding the behavior of urban air pollution is important en route for sustainable urban development (SUD). Malaysia is on its mission to be a developed country by year 2020 comprehends dealing with air pollution...Understanding the behavior of urban air pollution is important en route for sustainable urban development (SUD). Malaysia is on its mission to be a developed country by year 2020 comprehends dealing with air pollution is one of the indicators headed towards it. At present monitoring and managing air pollution in urban areas encompasses sophisticated air quality modeling and data acquisition. However, rapid developments in major cities cause difficulties in acquiring the city geometries. The existing method in acquiring city geometries data via ground or space measurement inspection such as field survey, photogrammetry, laser scanning, remote sensing or using architectural plans appears not to be practical because of its cost and efforts. Moreover, air monitoring stations deployed are intended for regional to global scale model whereby it is not accurate for urban areas with typical resolution of less than 2 km. Furthermore in urban areas, the pollutant dispersion movements are trapped between buildings initiating it to move vertically causing visualization complications which imply the limitations of existing visualization scheme that is based on two-dimensional (2D) framework. Therefore this paper aims is to perform groundwork assessment and discuss on the current scenario in Malaysia in the aspect of current policies towards SUD, air quality monitoring stations, scale model and detail discussion on air pollution dispersion model used called the Operational Street Pollution Model (OSPM). This research proposed the implementation of three-dimensional (3D) spatial city model as a new physical data input for OSPM. The five Level of Details (LOD) of 3D spatial city model shows the scale applicability for the dispersion model implementtation. Subsequently 3D spatial city model data commonly available on the web, by having a unified data model shows the advantages in easy data acquisition, 3D visualization of air pollution dispersion and improves visual analysis of air quality monitoring in urban areas.展开更多
Functional research on biological macromolecules must fcus on specific loca regions.PDBlocal is aweb-based tool developed to overcome the limitations of traditional molecular visualization tools forthre-dimensional(3D...Functional research on biological macromolecules must fcus on specific loca regions.PDBlocal is aweb-based tool developed to overcome the limitations of traditional molecular visualization tools forthre-dimensional(3D)inspection of local regions.PDBlocal provides an intuitive and easy-to-manipulate web page interface and some new useful functions.It can kep loca regions flashing,display sequence text that is dynamically consistent with the 3D structure in local appearance undermultiple local manipulations,use two scenes to help users inspect the same local region withdifferent statuses,list all historical manipulation statuses with a tree structure,llow users toannotate regions ofinterest,and save ll historical statuses and other data to a web server for futureresearch.PDBlocal has met expectations and shown satisfactory performance for both expert andnovice users.This tool is available at http:/labsystem.scuec.edu.cn/pdblocal/.展开更多
Visual arts refer to art experienced primarily through vision.3D visual optical art is one of them.Artists use their rich imagination and experience to combine light and objects to give viewers an unforgettable visual...Visual arts refer to art experienced primarily through vision.3D visual optical art is one of them.Artists use their rich imagination and experience to combine light and objects to give viewers an unforgettable visual experience.How-ever,the design process involves much trial and error;therefore,it is often very time-consuming.This has prompted many researchers to focus on proposing various algorithms to simplify the complicated design processes and help artists quickly realize the arts in their minds.To help computer graphics researchers interested in creating 3D visual optical art,we first classify and review relevant studies,then extract a general framework for solving 3D visual optical art design problems,and finally propose possible directions for future research.展开更多
In this paper, we summarize 3D perception-oriented algorithms for perceptually driven 3D video coding. Several perceptual ef- fects have been exploited for 2D video viewing; however, this is not yet the case for 3D vi...In this paper, we summarize 3D perception-oriented algorithms for perceptually driven 3D video coding. Several perceptual ef- fects have been exploited for 2D video viewing; however, this is not yet the case for 3D video viewing. 3D video requires depth perception, which implies binocular effects such as con fl icts, fusion, and rivalry. A better understanding of these effects is necessary for 3D perceptual compression, which provides users with a more comfortable visual experience for video that is de- livered over a channel with limited bandwidth. We present state-of-the-art of 3D visual attention models, 3D just-notice- able difference models, and 3D texture-synthesis models that address 3D human vision issues in 3D video coding and trans-mission.展开更多
Background:The perception of visual forms is crucial for effective interactions with our environment and for the recognition of visual objects.Thus,to determine the codes underlying this function is a fundamental theo...Background:The perception of visual forms is crucial for effective interactions with our environment and for the recognition of visual objects.Thus,to determine the codes underlying this function is a fundamental theoretical objective in the study of the visual forms perception.The vast majority of research in the field is based on a hypothetico-deductive approach.Thus,we first begin by formulating a theory,then we make predictions and finally we conduct experimental tests.After decades of application of this approach,the field remains far from having a consensus as to the traits underlying the representation of visual form.Our goal is to determine,without theoretical a priori or any bias whatsoever,the information underlying the discrimination and recognition of 3D visual forms in normal human adults.Methods:To this end,the adaptive bubble technique developed by Wang et al.[2011]is applied on six 3D synthetic objects under varying views from one test to another.This technique is based on the presentation of stimuli that are partially revealed through Gaussian windows,the location of which is random and the number of which is established in such a way as to maintain an established performance criterion.Gradually,the experimental program uses participants’performance to determine the stimulus regions that participants use to recognize objects.The synthetic objects used in this study are unfamiliar and were generated from a program produced at C.Edward Connor’s lab,Johns Hopkins University School of Medicine.Results:The results were integrated across participants to establish regions of presented stimuli that determine the observers’ability to recognize them-i.e.,diagnostic attributes.The results will be reported in graphical form with a Z scores mapping that will be superimposed on silhouettes of the objects presented during the experiment.This mapping makes it possible to quantify the importance of the different regions on the visible surface of an object for its recognition by the participants.Conclusions:The diagnostic attributes that have been identified are the best described in terms of surface fragments.Some of these fragments are located on or near the outer edge of the stimulus while others are relatively distant.The overlap is minimal between the effective attributes for the different points of view of the same object.This suggests that the traits underlying the recognition of objects are specific to the point of view.In other words,they do not generalize through the points of view.展开更多
3D visualization was established for noninvasive evaluation of neurovascular compression syndromes. MR-CISS (constructive interference in the steady state) is the most potent image source to depict neurovascular detai...3D visualization was established for noninvasive evaluation of neurovascular compression syndromes. MR-CISS (constructive interference in the steady state) is the most potent image source to depict neurovascular details. The purpose of this article is the conceptual view over the established technique of 3D visualization in the topography of aneurysms in the posterior circulation in relation to surrounding cranial nerves and the brainstem.展开更多
Data visualization empowers researchers to communicate their results that support scientific reasoning in an intuitive way.Three-dimension(3D)spatially resolved transcriptomic atlases constructed from multi-view and h...Data visualization empowers researchers to communicate their results that support scientific reasoning in an intuitive way.Three-dimension(3D)spatially resolved transcriptomic atlases constructed from multi-view and high-dimensional data have rapidly emerged as a powerful tool to unravel spatial gene expression patterns and cell type distribution in biological samples,revolutionizing the understanding of gene regulatory interactions and cell niches.However,limited accessible tools for data visualization impede the potential impact and application of this technology.Here we introduce VT3D,a visualization toolbox that allows users to explore 3D transcriptomic data,enabling gene expression projection to any 2D plane of interest,2D virtual slice creation and visualization,and interactive 3D data browsing with surface model plots.In addition,it can either work on personal devices in standalone mode or be hosted as a web-based server.We apply VT3D to multiple datasets produced by the most popular techniques,including both sequencing-based approaches(Stereo-seq,spatial transcriptomics,and Slide-seq)and imaging-based approaches(MERFISH and STARMap),and successfully build a 3D atlas database that allows interactive data browsing.We demonstrate that VT3D bridges the gap between researchers and spatially resolved transcriptomics,thus accelerating related studies such as embryogenesis and organogenesis processes.The source code of VT3D is available at https://github.com/BGI-Qingdao/VT3D,and the modeled atlas database is available at http://www.bgiocean.com/vt3d_example.展开更多
Pore network structure of ore body is a diffusion channel of leaching agent solution that exerts a significant influence on seepage.The ore body structure,pore distribution,pore and throat size,and pore network charac...Pore network structure of ore body is a diffusion channel of leaching agent solution that exerts a significant influence on seepage.The ore body structure,pore distribution,pore and throat size,and pore network characteristics of topsoil,weathered,and semiweathered layers of ionic rare earth ore in southern Jiangxi Province were explored in this study.The effect of leaching operation on the pore structure was investigated,and main factors affecting the seepage were analyzed.Results showed that the semiweathered layer presents a dense structure and a small number of unconnected pores.Pores of topsoil and weathered layers are mainly long and narrow column openings with some planar fractures.Even pore distribution and large size span were observed.Compared with the weathered layer,the topsoil layer demonstrates larger voids,smaller average pore volume and equivalent radius,and fewer coordination throats;however,the average equivalent radius of the throat in the topsoil layer is larger and largescale channels exist through ore body vertically.Hence,permeability of the topsoil layer is significantly higher than that of the weathered layer.Colloidal clay minerals migrate easily and the occurrence of silting in the small porosity blocks the throat and significantly decreases the permeability of the ore body in the leaching process.The equivalent radius of the throat is the key to the seepage.Reducing the migration of fine particles is an effective measure to protect the throat and shorten the leaching period.展开更多
Background Social distancing is an effective way to reduce the spread of the SARS-CoV-2 virus.Many students and researchers have already attempted to use computer vision technology to automatically detect human beings...Background Social distancing is an effective way to reduce the spread of the SARS-CoV-2 virus.Many students and researchers have already attempted to use computer vision technology to automatically detect human beings in the field of view of a camera and help enforce social distancing.However,because of the present lockdown measures in several countries,the validation of computer vision systems using large-scale datasets is a challenge.Methods In this paper,a new method is proposed for generating customized datasets and validating deep-learning-based computer vision models using virtual reality(VR)technology.Using VR,we modeled a digital twin(DT)of an existing office space and used it to create a dataset of individuals in different postures,dresses,and locations.To test the proposed solution,we implemented a convolutional neural network(CNN)model for detecting people in a limited-sized dataset of real humans and a simulated dataset of humanoid figures.Results We detected the number of persons in both the real and synthetic datasets with more than 90%accuracy,and the actual and measured distances were significantly correlated(r=0.99).Finally,we used intermittent-layer-and heatmap-based data visualization techniques to explain the failure modes of a CNN.Conclusions A new application of DTs is proposed to enhance workplace safety by measuring the social distance between individuals.The use of our proposed pipeline along with a DT of the shared space for visualizing both environmental and human behavior aspects preserves the privacy of individuals and improves the latency of such monitoring systems because only the extracted information is streamed.展开更多
3D terrain visualization of geographic information systems(GIS)data has become an important issue in recent years.This is due to the emergence of new geo-browsers such as Google Earth,widely popular among users.The av...3D terrain visualization of geographic information systems(GIS)data has become an important issue in recent years.This is due to the emergence of new geo-browsers such as Google Earth,widely popular among users.The availability of 3D representation tools has increased the demand for 3D terrain visualization.The aim of this paper is to review the literature related to the 3D terrain visualization of GIS data from the first map produced until the online mapping era.The reviews are divided into four different sections:manual visualization of 3D terrain,automated visualization of 3D terrain,online visualization of 3D terrain,and software for visualizing 3D terrain.Then,the paper compares between the different types of systems developed by various authors based on the capabilities and the limitations of the system.Some of the techniques have their own strengths and limitations which solve the problem in 3D terrain visualization.However,the research on improving 3D terrain visualization is still ongoing.This is due to the popularity of online environments and mobile devices that render 3D terrain.This review paper will help interested users understand the current state of 3D terrain visualization of GIS data in a better way.展开更多
In plant research,there is a demand for non-destructive and non-invasive trait measurement methods for phenotyping that can be used to accurately analyze various aspects of plants,such as stem length,leaf area,and lea...In plant research,there is a demand for non-destructive and non-invasive trait measurement methods for phenotyping that can be used to accurately analyze various aspects of plants,such as stem length,leaf area,and leaf inclination.In this study,a method for measuring the leaf geometric characteristics of poplar seedlings based on 3D visualization via the use of time-of-flight(ToF)and digital cameras was proposed.Firstly,the average distance density function method was applied to process outliers of leaves.Secondly,to improve the accuracy of data fitting,a specific method using the angle of adjacent two-point normal vectors was introduced to filter redundant data,kept essential sample values as the control points,and then used the control points to fit the leaf surface based on non-uniform rational B-splines(NURBS).At the same time,NURBS was used to fit the trunk according to its control points and an iterative method to fit the other branches.Finally,3D visualization of poplar seedlings was achieved,and leaf traits,including leaf width,leaf length,leaf area,and leaf inclination angle,were calculated.To obtain accurate results,multiple experiments were conducted including assessments of poplar seedlings exhibiting normal growth and those grown under water shortage.The results of the proposed method were compared with the real values of the leaves.The RMSE for leaf width,leaf length,leaf area,and leaf angle were 0.18 cm,0.21 cm,1.14 cm^(2),and 1.97°,respectively.The results proved that this approach could be used to accurately measure the leaf characteristics of poplar seedlings via visualization.展开更多
Adaptive rendering of large urban building models has become an important research issue in three-dimensional(3D)geographic information system(GIS)applications.This study explores a way for rendering web-based 3D urba...Adaptive rendering of large urban building models has become an important research issue in three-dimensional(3D)geographic information system(GIS)applications.This study explores a way for rendering web-based 3D urban building models.A client-server hybrid rendering approach is presented for large 3D city models,stored on a remote server through a network.The approach combines an efficient multi-hierarchical building representation with a novel image-based method,3D image impostor generated on demand by a remote server.This approach allows transferring complex scenes progressively while keeping high visualization quality.We also evaluated the rendering and data transferring performance of the proposed approach.展开更多
Despite recent advances in mine health and safety, roof collapse and instabilities are still the leading causes of injury and fatality in underground mining operations. Improving safety and optimum design of ground su...Despite recent advances in mine health and safety, roof collapse and instabilities are still the leading causes of injury and fatality in underground mining operations. Improving safety and optimum design of ground support requires good and reliable ground characterization. While many geophysical methods have been developed for ground characterizations, their accuracy is insufficient for customized ground support design of underground workings. The actual measurements on the samples of the roof and wall strata from the exploration boring are reliable but the related holes are far apart, thus unsuitable for design purposes. The best source of information could be the geological back mapping of the roof and walls, but this is disruptive to mining operations, and provided information is only from rock surface.Interpretation of the data obtained from roof bolt drilling can offer a good and reliable source of information that can be used for ground characterization and ground support design and evaluations. This paper offers a brief review of the mine roof characterization methods, followed by introduction and discussion of the roof characterization methods by instrumented roof bolters. A brief overview of the results of the preliminary study and initial testing on an instrumented drill and summary of the suggested improvements are also discussed.展开更多
基金Supported by research grants from the National Key Research and Development Program of China(No.2020YFE0204400)the National Natural Science Foundation of China(No.82271042+1 种基金No.52203191)the Zhejiang Province Key Research and Development Program(No.2023C03090).
文摘●AIM:To determine the teaching effects of a real-time three dimensional(3D)visualization system in the operating room for early-stage phacoemulsification training.●METHODS:A total of 10 ophthalmology residents of the first-year postgraduate were included.All the residents were novices to cataract surgery.Real-time cataract surgical observations were performed using a custom-built 3D visualization system.The training lasted 4wk(32h)in all.A modified International Council of Ophthalmology’s Ophthalmology Surgical Competency Assessment Rubric(ICO-OSCAR)containing 4 specific steps of cataract surgery was applied.The self-assessment(self)and expert-assessment(expert)were performed through the microsurgical attempts in the wet lab for each participant.●RESULTS:Compared with pre-training assessments(self 3.2±0.8,expert 2.5±0.6),the overall mean scores of posttraining(self 5.2±0.4,expert 4.7±0.6)were significantly improved after real-time observation training of 3D visualization system(P<0.05).Scores of 4 surgical items were significantly improved both self and expert assessment after training(P<0.05).●CONCLUSION:The 3D observation training provides novice ophthalmic residents with a better understanding of intraocular microsurgical techniques.It is a useful tool to improve teaching efficiency of surgical education.
基金Supported by the National Natural Science Foundation of China (62202346)Hubei Key Research and Development Program (2021BAA042)+3 种基金Open project of Engineering Research Center of Hubei Province for Clothing Information (2022HBCI01)Wuhan Applied Basic Frontier Research Project (2022013988065212)MIIT′s AI Industry Innovation Task Unveils Flagship Projects (Key Technologies,Equipment,and Systems for Flexible Customized and Intelligent Manufacturing in the Clothing Industry)Hubei Science and Technology Project of Safe Production Special Fund (Scene Control Platform Based on Proprioception Information Computing of Artificial Intelligence)。
文摘Background Intelligent garments,a burgeoning class of wearable devices,have extensive applications in domains such as sports training and medical rehabilitation.Nonetheless,existing research in the smart wearables domain predominantly emphasizes sensor functionality and quantity,often skipping crucial aspects related to user experience and interaction.Methods To address this gap,this study introduces a novel real-time 3D interactive system based on intelligent garments.The system utilizes lightweight sensor modules to collect human motion data and introduces a dual-stream fusion network based on pulsed neural units to classify and recognize human movements,thereby achieving real-time interaction between users and sensors.Additionally,the system incorporates 3D human visualization functionality,which visualizes sensor data and recognizes human actions as 3D models in real time,providing accurate and comprehensive visual feedback to help users better understand and analyze the details and features of human motion.This system has significant potential for applications in motion detection,medical monitoring,virtual reality,and other fields.The accurate classification of human actions contributes to the development of personalized training plans and injury prevention strategies.Conclusions This study has substantial implications in the domains of intelligent garments,human motion monitoring,and digital twin visualization.The advancement of this system is expected to propel the progress of wearable technology and foster a deeper comprehension of human motion.
文摘The conventional 2D design method of culverts separated from 3D model cannot directly visualize the process of creating and renewal process. This paper explores graphics application framework of Open GL based on MFC, developing the 3D visualization system of hydraulic culvert. This system effectively integrats with building design, structural design and parametric design and image processing technology. The results can be shown by 3D visualization design.
文摘3D stereoscopic visualization technology is coming into more and more common use in the field of entertainment,and this technology is also beginning to cut a striking figure in casting industry and scientific research.The history,fundamental principle,and devices of 3D stereoscopic visualization technology are reviewed in this paper.The authors’research achievements on the 3D stereoscopic visualization technology in the modeling and simulation of the casting process are presented.This technology can be used for the observation of complex 3D solid models of castings and the simulated results of solidification processes such as temperature,fluid flow,displacement,stress strain and microstructure,as well as the predicted defects such as shrinkage/porosity,cracks,and deformation.It can also be used for other areas relating to 3D models,such as assembling of dies,cores,etc.Several cases are given to compare the illustration of simulated results by traditional images and red-blue 3D stereoscopic images.The spatial shape is observed better by the new method.The prospect of3D stereoscopic visualization in the casting aspect is discussed as well.The need for aided-viewing devices is still the most prominent problem of 3D stereoscopic visualization technology.However,3D stereoscopic visualization represents the tendency of visualization technology in the future;and as the problem is solved in the years ahead,great breakthroughs will certainly be made for its application in casting design and modeling and simulation of the casting processes.
文摘Essentially, CesiumJS—which can be accessed through the link, http://cesiumjs.org, is an open-source JavaScript library for creating virtual globe environment in performance effective, high quality of rendering, precision, and user friendly. It is a wonderful tool for 3D-themed visualizations of earth. CesiumJS has a number of data sources, but none of them supports vector tile format. This article explains how to visualize Mapbox vector tiles in a CesiumJS virtual globe environment. CartoDB/BigQuery hosts vector tiles, and a process for producing vector tiles from massive vector data using the BigQuery tiler of CartoDB has been provided.
基金We acknowledge the funding support from the National Natural Science Foundation of China Youth Fund(Grant No.52004019)the National Natural Science Foundation of China(Grant No.41825018)China Postdoctoral Science Foundation(Grant No.2023M733481).
文摘Rock-encased-backfill(RB)structures are common in underground mining,for example in the cut-andfill and stoping methods.To understand the effects of cyclic excavation and blasting activities on the damage of these RB structures,a series of triaxial stepwise-increasing-amplitude cyclic loading experiments was conducted with cylindrical RB specimens(rock on outside,backfill on inside)with different volume fractions of rock(VF=0.48,0.61,0.73,and 0.84),confining pressures(0,6,9,and 12 MPa),and cyclic loading rates(200,300,400,and 500 N/s).The damage evolution and meso-crack formation during the cyclic tests were analyzed with results from stress-strain hysteresis loops,acoustic emission events,and post-failure X-ray 3D fracture morphology.The results showed significant differences between cyclic and monotonic loadings of RB specimens,particularly with regard to the generation of shear microcracks,the development of stress memory and strain hardening,and the contact forces and associated friction that develops along the rock-backfill interface.One important finding is that as a function of the number of cycles,the elastic strain increases linearly and the dissipated energy increases exponentially.Also,compared with monotonic loading,the cyclic strain hardening characteristics are more sensitive to rising confining pressures during the initial compaction stage.Another finding is that compared with monotonic loading,more shear microcracks are generated during every reloading stage,but these microcracks tend to be dispersed and lessen the likelihood of large shear fracture formation.The transition from elastic to plastic behavior varies depending on the parameters of each test(confinement,volume fraction,and cyclic rate),and an interesting finding was that the transformation to plastic behavior is significantly lower under the conditions of 0.73 rock volume fraction,400 N/s cyclic loading rate,and 9 MPa confinement.All the findings have important practical implications on the ability of backfill to support underground excavations.
基金This work was supported by National Natural Science Foundation of China(91850202,61775085,11774256)Natural Science Foundation of Guangdong Province(2016A030312010,2020A1515010958)Science and Technology Innovation Commission of Shenzhen(KQTD2017033011044403,ZDSYS201703031605029).
文摘Digital holography has high potentials for future 3D imaging and display technology.We present a method for a dynamic full-color digital holographic 3D display on single digital micro-mirror device(DMD)with full-color,high-speed and high-fidelity characteristics.We combine the square regions of adjacent micro-mirrors into super-pixels that can modulate amplitude and phase independently.Gray images are achieved by amplitude modulation and precise positioning of each color is achieved by phase modulation.The proposed method realizes a full-color imaging based on the three primary colors and achieves measured structural similarity of more than 88%and color similarity of more than 98%,while retaining the high switch speed of 9 kHz,thus achieving dynamic full-color 3D display on charge-coupled device(CCD).
基金Major funding for this research was provided by the Ministry of Higher Education Malaysia and partially funded by the Land Surveyors Board of Malaysia.
文摘Understanding the behavior of urban air pollution is important en route for sustainable urban development (SUD). Malaysia is on its mission to be a developed country by year 2020 comprehends dealing with air pollution is one of the indicators headed towards it. At present monitoring and managing air pollution in urban areas encompasses sophisticated air quality modeling and data acquisition. However, rapid developments in major cities cause difficulties in acquiring the city geometries. The existing method in acquiring city geometries data via ground or space measurement inspection such as field survey, photogrammetry, laser scanning, remote sensing or using architectural plans appears not to be practical because of its cost and efforts. Moreover, air monitoring stations deployed are intended for regional to global scale model whereby it is not accurate for urban areas with typical resolution of less than 2 km. Furthermore in urban areas, the pollutant dispersion movements are trapped between buildings initiating it to move vertically causing visualization complications which imply the limitations of existing visualization scheme that is based on two-dimensional (2D) framework. Therefore this paper aims is to perform groundwork assessment and discuss on the current scenario in Malaysia in the aspect of current policies towards SUD, air quality monitoring stations, scale model and detail discussion on air pollution dispersion model used called the Operational Street Pollution Model (OSPM). This research proposed the implementation of three-dimensional (3D) spatial city model as a new physical data input for OSPM. The five Level of Details (LOD) of 3D spatial city model shows the scale applicability for the dispersion model implementtation. Subsequently 3D spatial city model data commonly available on the web, by having a unified data model shows the advantages in easy data acquisition, 3D visualization of air pollution dispersion and improves visual analysis of air quality monitoring in urban areas.
基金supported by the International Science and Technology Cooperation Key Projects of the Chinese Ministry of Science and Technology(2009DFB30340)National Major Projects of China(2016ZX08010004-004)+2 种基金National Natural Sciences Foundation of China(81373379)Natural Science Foundation of Hubei Province of China(2012FFB07402)Fundamental Research Funds for the Central Universities in China(SouthCentral University for Nationalities,CZY12004).
文摘Functional research on biological macromolecules must fcus on specific loca regions.PDBlocal is aweb-based tool developed to overcome the limitations of traditional molecular visualization tools forthre-dimensional(3D)inspection of local regions.PDBlocal provides an intuitive and easy-to-manipulate web page interface and some new useful functions.It can kep loca regions flashing,display sequence text that is dynamically consistent with the 3D structure in local appearance undermultiple local manipulations,use two scenes to help users inspect the same local region withdifferent statuses,list all historical manipulation statuses with a tree structure,llow users toannotate regions ofinterest,and save ll historical statuses and other data to a web server for futureresearch.PDBlocal has met expectations and shown satisfactory performance for both expert andnovice users.This tool is available at http:/labsystem.scuec.edu.cn/pdblocal/.
基金This work is supported by the National Natural Science Foundation of China,No.62025207.
文摘Visual arts refer to art experienced primarily through vision.3D visual optical art is one of them.Artists use their rich imagination and experience to combine light and objects to give viewers an unforgettable visual experience.How-ever,the design process involves much trial and error;therefore,it is often very time-consuming.This has prompted many researchers to focus on proposing various algorithms to simplify the complicated design processes and help artists quickly realize the arts in their minds.To help computer graphics researchers interested in creating 3D visual optical art,we first classify and review relevant studies,then extract a general framework for solving 3D visual optical art design problems,and finally propose possible directions for future research.
文摘In this paper, we summarize 3D perception-oriented algorithms for perceptually driven 3D video coding. Several perceptual ef- fects have been exploited for 2D video viewing; however, this is not yet the case for 3D video viewing. 3D video requires depth perception, which implies binocular effects such as con fl icts, fusion, and rivalry. A better understanding of these effects is necessary for 3D perceptual compression, which provides users with a more comfortable visual experience for video that is de- livered over a channel with limited bandwidth. We present state-of-the-art of 3D visual attention models, 3D just-notice- able difference models, and 3D texture-synthesis models that address 3D human vision issues in 3D video coding and trans-mission.
文摘Background:The perception of visual forms is crucial for effective interactions with our environment and for the recognition of visual objects.Thus,to determine the codes underlying this function is a fundamental theoretical objective in the study of the visual forms perception.The vast majority of research in the field is based on a hypothetico-deductive approach.Thus,we first begin by formulating a theory,then we make predictions and finally we conduct experimental tests.After decades of application of this approach,the field remains far from having a consensus as to the traits underlying the representation of visual form.Our goal is to determine,without theoretical a priori or any bias whatsoever,the information underlying the discrimination and recognition of 3D visual forms in normal human adults.Methods:To this end,the adaptive bubble technique developed by Wang et al.[2011]is applied on six 3D synthetic objects under varying views from one test to another.This technique is based on the presentation of stimuli that are partially revealed through Gaussian windows,the location of which is random and the number of which is established in such a way as to maintain an established performance criterion.Gradually,the experimental program uses participants’performance to determine the stimulus regions that participants use to recognize objects.The synthetic objects used in this study are unfamiliar and were generated from a program produced at C.Edward Connor’s lab,Johns Hopkins University School of Medicine.Results:The results were integrated across participants to establish regions of presented stimuli that determine the observers’ability to recognize them-i.e.,diagnostic attributes.The results will be reported in graphical form with a Z scores mapping that will be superimposed on silhouettes of the objects presented during the experiment.This mapping makes it possible to quantify the importance of the different regions on the visible surface of an object for its recognition by the participants.Conclusions:The diagnostic attributes that have been identified are the best described in terms of surface fragments.Some of these fragments are located on or near the outer edge of the stimulus while others are relatively distant.The overlap is minimal between the effective attributes for the different points of view of the same object.This suggests that the traits underlying the recognition of objects are specific to the point of view.In other words,they do not generalize through the points of view.
文摘3D visualization was established for noninvasive evaluation of neurovascular compression syndromes. MR-CISS (constructive interference in the steady state) is the most potent image source to depict neurovascular details. The purpose of this article is the conceptual view over the established technique of 3D visualization in the topography of aneurysms in the posterior circulation in relation to surrounding cranial nerves and the brainstem.
基金supported by the General Program(Key Program,Major Research Plan)of National Natural Science Foundation of China(No.32170439).
文摘Data visualization empowers researchers to communicate their results that support scientific reasoning in an intuitive way.Three-dimension(3D)spatially resolved transcriptomic atlases constructed from multi-view and high-dimensional data have rapidly emerged as a powerful tool to unravel spatial gene expression patterns and cell type distribution in biological samples,revolutionizing the understanding of gene regulatory interactions and cell niches.However,limited accessible tools for data visualization impede the potential impact and application of this technology.Here we introduce VT3D,a visualization toolbox that allows users to explore 3D transcriptomic data,enabling gene expression projection to any 2D plane of interest,2D virtual slice creation and visualization,and interactive 3D data browsing with surface model plots.In addition,it can either work on personal devices in standalone mode or be hosted as a web-based server.We apply VT3D to multiple datasets produced by the most popular techniques,including both sequencing-based approaches(Stereo-seq,spatial transcriptomics,and Slide-seq)and imaging-based approaches(MERFISH and STARMap),and successfully build a 3D atlas database that allows interactive data browsing.We demonstrate that VT3D bridges the gap between researchers and spatially resolved transcriptomics,thus accelerating related studies such as embryogenesis and organogenesis processes.The source code of VT3D is available at https://github.com/BGI-Qingdao/VT3D,and the modeled atlas database is available at http://www.bgiocean.com/vt3d_example.
基金supported by the National Natural Science Foundation of China(Nos.51774153,92062110)National Key Research and Development Program of China(No.2021YFC2901702)。
文摘Pore network structure of ore body is a diffusion channel of leaching agent solution that exerts a significant influence on seepage.The ore body structure,pore distribution,pore and throat size,and pore network characteristics of topsoil,weathered,and semiweathered layers of ionic rare earth ore in southern Jiangxi Province were explored in this study.The effect of leaching operation on the pore structure was investigated,and main factors affecting the seepage were analyzed.Results showed that the semiweathered layer presents a dense structure and a small number of unconnected pores.Pores of topsoil and weathered layers are mainly long and narrow column openings with some planar fractures.Even pore distribution and large size span were observed.Compared with the weathered layer,the topsoil layer demonstrates larger voids,smaller average pore volume and equivalent radius,and fewer coordination throats;however,the average equivalent radius of the throat in the topsoil layer is larger and largescale channels exist through ore body vertically.Hence,permeability of the topsoil layer is significantly higher than that of the weathered layer.Colloidal clay minerals migrate easily and the occurrence of silting in the small porosity blocks the throat and significantly decreases the permeability of the ore body in the leaching process.The equivalent radius of the throat is the key to the seepage.Reducing the migration of fine particles is an effective measure to protect the throat and shorten the leaching period.
文摘Background Social distancing is an effective way to reduce the spread of the SARS-CoV-2 virus.Many students and researchers have already attempted to use computer vision technology to automatically detect human beings in the field of view of a camera and help enforce social distancing.However,because of the present lockdown measures in several countries,the validation of computer vision systems using large-scale datasets is a challenge.Methods In this paper,a new method is proposed for generating customized datasets and validating deep-learning-based computer vision models using virtual reality(VR)technology.Using VR,we modeled a digital twin(DT)of an existing office space and used it to create a dataset of individuals in different postures,dresses,and locations.To test the proposed solution,we implemented a convolutional neural network(CNN)model for detecting people in a limited-sized dataset of real humans and a simulated dataset of humanoid figures.Results We detected the number of persons in both the real and synthetic datasets with more than 90%accuracy,and the actual and measured distances were significantly correlated(r=0.99).Finally,we used intermittent-layer-and heatmap-based data visualization techniques to explain the failure modes of a CNN.Conclusions A new application of DTs is proposed to enhance workplace safety by measuring the social distance between individuals.The use of our proposed pipeline along with a DT of the shared space for visualizing both environmental and human behavior aspects preserves the privacy of individuals and improves the latency of such monitoring systems because only the extracted information is streamed.
文摘3D terrain visualization of geographic information systems(GIS)data has become an important issue in recent years.This is due to the emergence of new geo-browsers such as Google Earth,widely popular among users.The availability of 3D representation tools has increased the demand for 3D terrain visualization.The aim of this paper is to review the literature related to the 3D terrain visualization of GIS data from the first map produced until the online mapping era.The reviews are divided into four different sections:manual visualization of 3D terrain,automated visualization of 3D terrain,online visualization of 3D terrain,and software for visualizing 3D terrain.Then,the paper compares between the different types of systems developed by various authors based on the capabilities and the limitations of the system.Some of the techniques have their own strengths and limitations which solve the problem in 3D terrain visualization.However,the research on improving 3D terrain visualization is still ongoing.This is due to the popularity of online environments and mobile devices that render 3D terrain.This review paper will help interested users understand the current state of 3D terrain visualization of GIS data in a better way.
基金This work was financially supported by the National Key Research and Development Program of China(2017YFD0600905-1)the Priority Academic Program Development of Jiangsu Higher Education Institutionsthe Jiangsu Government Scholarship for Overseas Studies(JS-2014-013).
文摘In plant research,there is a demand for non-destructive and non-invasive trait measurement methods for phenotyping that can be used to accurately analyze various aspects of plants,such as stem length,leaf area,and leaf inclination.In this study,a method for measuring the leaf geometric characteristics of poplar seedlings based on 3D visualization via the use of time-of-flight(ToF)and digital cameras was proposed.Firstly,the average distance density function method was applied to process outliers of leaves.Secondly,to improve the accuracy of data fitting,a specific method using the angle of adjacent two-point normal vectors was introduced to filter redundant data,kept essential sample values as the control points,and then used the control points to fit the leaf surface based on non-uniform rational B-splines(NURBS).At the same time,NURBS was used to fit the trunk according to its control points and an iterative method to fit the other branches.Finally,3D visualization of poplar seedlings was achieved,and leaf traits,including leaf width,leaf length,leaf area,and leaf inclination angle,were calculated.To obtain accurate results,multiple experiments were conducted including assessments of poplar seedlings exhibiting normal growth and those grown under water shortage.The results of the proposed method were compared with the real values of the leaves.The RMSE for leaf width,leaf length,leaf area,and leaf angle were 0.18 cm,0.21 cm,1.14 cm^(2),and 1.97°,respectively.The results proved that this approach could be used to accurately measure the leaf characteristics of poplar seedlings via visualization.
基金supported by the National Natural Science Foundation of China(No.60502008)the National 863 High-Tech Program of China(No.2011AA120302).
文摘Adaptive rendering of large urban building models has become an important research issue in three-dimensional(3D)geographic information system(GIS)applications.This study explores a way for rendering web-based 3D urban building models.A client-server hybrid rendering approach is presented for large 3D city models,stored on a remote server through a network.The approach combines an efficient multi-hierarchical building representation with a novel image-based method,3D image impostor generated on demand by a remote server.This approach allows transferring complex scenes progressively while keeping high visualization quality.We also evaluated the rendering and data transferring performance of the proposed approach.
基金supported by the funding of the National Institute for Occupational Safety and Health under a contract with the Pennsylvania State University as part of the capacity building in ground supportthe funding from TüBITAK of Turkey has been used to support the sabbatical leave of Dr.Kahraman who made some contributions to this study
文摘Despite recent advances in mine health and safety, roof collapse and instabilities are still the leading causes of injury and fatality in underground mining operations. Improving safety and optimum design of ground support requires good and reliable ground characterization. While many geophysical methods have been developed for ground characterizations, their accuracy is insufficient for customized ground support design of underground workings. The actual measurements on the samples of the roof and wall strata from the exploration boring are reliable but the related holes are far apart, thus unsuitable for design purposes. The best source of information could be the geological back mapping of the roof and walls, but this is disruptive to mining operations, and provided information is only from rock surface.Interpretation of the data obtained from roof bolt drilling can offer a good and reliable source of information that can be used for ground characterization and ground support design and evaluations. This paper offers a brief review of the mine roof characterization methods, followed by introduction and discussion of the roof characterization methods by instrumented roof bolters. A brief overview of the results of the preliminary study and initial testing on an instrumented drill and summary of the suggested improvements are also discussed.