Application of 3D stereoscopic visualization technology in casting aspect

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.

Large-scale spatial data visualization method based on augmented reality

Background A task assigned to space exploration satellites involves detecting the physical environment within a certain space.However,space detection data are complex and abstract.These data are not conducive for researchers'visual perceptions of the evolution and interaction of events in the space environment.Methods A time-series dynamic data sampling method for large-scale space was proposed for sample detection data in space and time,and the corresponding relationships between data location features and other attribute features were established.A tone-mapping method based on statistical histogram equalization was proposed and applied to the final attribute feature data.The visualization process is optimized for rendering by merging materials,reducing the number of patches,and performing other operations.Results The results of sampling,feature extraction,and uniform visualization of the detection data of complex types,long duration spans,and uneven spatial distributions were obtained.The real-time visualization of large-scale spatial structures using augmented reality devices,particularly low-performance devices,was also investigated.Conclusions The proposed visualization system can reconstruct the three-dimensional structure of a large-scale space,express the structure and changes in the spatial environment using augmented reality,and assist in intuitively discovering spatial environmental events and evolutionary rules.

Mixed reality for visualization of orthopedic surgical anatomy

In the modern era,preoperative planning is substantially facilitated by artificial reality technologies,which permit a better understanding of patient anatomy,thus increasing the safety and accuracy of surgical interventions.In the field of orthopedic surgery,the increase in safety and accuracy improves treatment quality and orthopedic patient outcomes.Artificial reality technologies,which include virtual reality(VR),augmented reality(AR),and mixed reality(MR),use digital images obtained from computed tomography or magnetic resonance imaging.VR replaces the user’s physical environment with one that is computer generated.AR and MR have been defined as technologies that permit the fusing of the physical with the virtual environment,enabling the user to interact with both physical and virtual objects.MR has been defined as a technology that,in contrast to AR,enables users to visualize the depth and perspective of the virtual models.We aimed to shed light on the role that MR can play in the visualization of orthopedic surgical anatomy.The literature suggests that MR could be a valuable tool in orthopedic surgeon’s hands for visualization of the anatomy.However,we remark that confusion exists in the literature concerning the characteristics of MR.Thus,a more clear description of MR is needed in orthopedic research,so that the potential of this technology can be more deeply understood.

Severe hematuria due to vesical varices in a patient with portal hypertension:A case report

BACKGROUND Hematuria is one of the most common clinical symptoms for urologists and is typically observed in urinary system tumors,prostate hyperplasia,and urinary stone disease.Hematuria due to vesical varices is very rare,and only a few cases have been reported since 1989.We report the first case of vesical varices due to portal hypertension with aberrant development and functioning of the genitourinary system along with the complete diagnosis and treatment process.CASE SUMMARY This patient was a 53-year-old man with a history of aberrant development of the genitourinary system and hepatitis B-associated cirrhosis.He was admitted to the emergency department with severe hematuria and bladder clot tamponade.Many abnormally dilated blood vessels were found surrounding the bladder in the pelvis by color Doppler ultrasound,contrast-enhanced computed tomography,and three-dimensional visualization technology.It was difficult to perform transurethral cystoscopy and hemostasis in this patient,so we performed open surgical bladder exploration for hemostasis and surgical devascularization around the bladder.CONCLUSION Urologists should improve the understanding of the pathophysiology,clinical manifestations,diagnosis,and treatment of vesical varices.This case may be presented as a reference for the diagnosis and management of severe hematuria due to vesical varices.

Carbon Emission Cycle and Literature Measurement of Carbon Fiber Vehicles

Carbon fiber is a kind of high-temperature fiber with high modulus and strength characteristics.Carbon fiber material is made of carbon fiber braid with carbon content>90%.Among them,resin-based carbon fiber reinforced composite material is often used as automotive structural material.Compared with the A36 steel commonly used in automobiles,the T300/5208 carbon fiber reinforced epoxy resin composite commonly used in automobiles has a higher tensile strength of 2500-3300 MPa and a lower density of 6.25 g/cm 3,showing great performance advantages.In this paper,by analyzing the trend of automobile lightweight,and exploring the development prospects of carbon fiber in the field of automobile lightweight,the literature in the Elsevier database is analyzed by scientific measurement analysis method,and the research hotspot in the field is listed.The relationship between the development of fiber materials and the promotion of policies is analyzed by comparing the number of carbon fiber automobile literature publications and key event nodes.This paper proposes a keyword-based influence calculation method.Through drawing analysis tools of information visualization scientific knowledge map and scientific measurement methods of keyword,it proposes the scientific measurement analysis literature of on-board carbon fiber,explores and discusses some frontier directions of automotive carbon fiber materials.The research provides reference for studying automobile lightweight carbon fiber material.

Electromagnetic System Design and Visual Simulation

An electromagnet design system is developed using Visual C++ language and OpenGL technology to visualize parametric 3D model. The system consists of primary design, optimization design, dynamic and static characteristics, and visual simulation. All empirical parameters and curves used in design process are stored in database. Through human-computer interactions, an electromagnetic system can be designed conveniently with the results and characteristics curves displayed in graphic model. Using this system can greatly shorten the process of product design, and the results satisfy technical requirements.

Corneal biomechanical data and biometric parameters measured with Scheimpflug-based devices on normal corneas

AIM： To analyze the correlations between ocular biomechanical and biometric data of the eye,measured by Scheimpflug-based devices on healthy subjects.METHODS： Three consecutive measurements were carried out using the corneal visualization Scheimpflug technology（Cor Vis ST） device on healthy eyes and the 10 device-specific parameters were recorded.Pentacam HR-derived parameters（corneal curvature radii on the anterior and posterior surfaces;apical pachymetry;corneal volume;corneal aberration data;depth,volume and angle of the anterior chamber） and axial length（AL） from IOLMaster were correlated with the 10 specific CorV is ST parameters.RESULTS： Measurements were conducted in 43 eyes of 43 volunteers（age 61.24±15.72y）.The 10 specific Cor Vis ST data showed significant relationships with corneal curvature radii both on the anterior and posterior surface,pachymetric data,root mean square（RMS） data of lower-order aberrations,and posterior RMS of higher-order aberrations and spherical aberration of the posterior cornea.Anterior chamber depth showed a significant relationship,but there were no significant correlations between corneal volume,anterior chamber volume,mean chamber angle or AL and the 10 specific CorV is ST parameters.CONCLUSION： Cor Vis ST-generated parameters are influenced by corneal curvature radii,some corneal RMS data,but corneal volume,anterior chamber volume,chamber angle and AL have no correlation with the biomechan-ical parameters.The parameters measured by CorV is ST seem to refer mostly to corneal properties of the eye.

Call for Papers Special Issue of Tsinghua Science and Technology on Visualization and Computer Graphics

Tsinghua Science and Technology was started publication in 1996. It is an international academic journal sponsored by Tsinghua University and is published bimonthly. This journal aims at presenting the up-to-date scientific achievements in computer science and other IT fields. It is indexed by Ei and other abstracting indexes. From 2012, the journal enters into IEEE Xplore Digital Library