Utility of real-time 3D visualization system in the early stage of phacoemulsification training

●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.

A survey of real-time rendering on Web3D application

Background In recent years, with the rapid development of mobile Internet and Web3D technologies, a large number of web-based online 3D visualization applications have emerged. Web3D applications, including Web3D online tourism, Web3D online architecture, Web3D online education environment, Web3D online medical care, and Web3D online shopping are examples of these applications that leverage 3D rendering on the web. These applications have pushed the boundaries of traditional web applications that use text, sound, image, video, and 2D animation as their main communication media, and resorted to 3D virtual scenes as the main interaction object, enabling a user experience that delivers a strong sense of immersion. This paper approached the emerging Web3D applications that generate stronger impacts on people's lives through “real-time rendering technology”, which is the core technology of Web3D. This paper discusses all the major 3D graphics APIs of Web3D and the well-known Web3D engines at home and abroad and classify the real-time rendering frameworks of Web3D applications into different categories. Results Finally, this study analyzed the specific demand posed by different fields to Web3D applications by referring to the representative Web3D applications in each particular field. Conclusions Our survey results show that Web3D applications based on real-time rendering have in-depth sectors of society and even family, which is a trend that has influence on every line of industry.

3D打印实物模型在颈椎疾患住院医师规范化培训教学中的应用和探讨

目的探讨3 D打印实物模型在提高颈椎疾患住院医师规范化培训(简称住培)教学效果中的作用。方法选取参加骨科住培的颈椎疾患学习的住院医师80名为研究对象,随机分为两组,观察组(40人)以幻灯讲解加3 D打印实物模型教学,对照组(40人)采用幻灯讲解教学。课后即时和课后1月分别对住院医师的知识掌握情况和诊疗技术进行现场测试,利用问卷的形式对住院医师的满意度和参与兴趣(10分法)进行调查。结果课后即时观察组的知识掌握情况和对照组相当(P>0.05),但是观察组的诊疗技术测试成绩显著高于对照组(P<0.05),观察组的满意度和参与兴趣评分均显著高于对照组,两者对比差异有统计学意义(均P<0.05);课后1月时,观察组的知识掌握情况和诊疗技术测试成绩均显著高于对照组(均P<0.05)。结论3 D打印实物模型应用于颈椎疾患住培的带教中,可显著提高教学效果,提升住院医师的满意度和参与兴趣,值得在住培教学中推广。

Performance Evaluation of Three-Dimensional UWB Real-Time Locating Auto-Positioning System for Fire Rescue

Fire rescue challenges and solutions have evolved from straightfor-ward plane rescue to encompass 3D space due to the rise of high-rise city buildings.Hence,this study facilitates a system with quick and simplified on-site launching and generates real-time location data,enabling fire rescuers to arrive at the intended spot faster and correctly for effective and precise rescue.Auto-positioning with step-by-step instructions is proposed when launching the locating system,while no extra measuring instrument like Total Station(TS)is needed.Real-time location tracking is provided via a 3D space real-time locating system(RTLS)constructed using Ultra-wide Bandwidth technology(UWB),which requires electromagnetic waves to pass through concrete walls.A hybrid weighted least squares with a time difference of arrival(WLS/TDOA)positioning method is proposed to address real path-tracking issues in 3D space and to meet RTLS requirements for quick computing in real-world applications.The 3D WLS/TDOA algorithm is theoretically constructed with the Cramer-Rao lower bound(CRLB).The computing complexity is reduced to the lower bound for embedded hardware to directly compute the time differential of the arriving signals using the time-to-digital converter(TDC).The results of the experiments show that the errors are controlled when the positioning algorithm is applied in various complicated situations to fulfill the requirements of engineering applications.The statistical analysis of the data reveals that the proposed UWB RTLS auto-positioning system can track target tags with an accuracy of 0.20 m.

基于实时3D鹰眼手术系统的CBL教学在脊柱肿瘤外科住培教学中的应用

目的研究基于实时3 D鹰眼手术系统的CBL教学在脊柱肿瘤外科住院医师规范化培训(简称住培)带教中的应用情况。方法选取2020年7月至2022年12月脊柱肿瘤外科住培的48名学员研究对象,随机分为观察组与对照组。观察组采用实时3 D手术系统的CBL教学,对照组则利用传统的住培教学方案开展脊柱肿瘤外科教学。比较两组住院医师出入科考试、技能操作考核以及学员对教学过程、课堂氛围与满意度的问卷调查结果。结果观察组与对照组的入科成绩差异无统计学意义(P>0.05)。课程结束后出科考核成绩,在理论考试成绩方面,观察组总成绩(76.00±6.30)分明显高于对照组(68.75±7.46)分,且在脊柱解剖学知识以及影像学知识方面成绩更加优秀,差异均有统计学意义(均P<0.05)。问卷调查提示,观察组课堂气氛、疾病认识程度、手术操作的掌握程度以及课堂总满意度都明显优于对照组,差异有统计学意义(均P<0.05)。结论基于实时3 D手术系统的CBL教学在脊柱肿瘤的住培教学中有较明显的优势,在医师培养中具有良好的发展前景。

用Real-time 3D技术制作VR小品

三维技术以前给人们的印象就是三维动画和CG作品，特别是三维动画，最深入人心，不过三维动画不具有交互性，不能指望依靠它实现什么互动功能。实时三维技术虽然在很早以前就有了，但主要用于游戏开发、军事科研、大型仿真等领域。

Application of real-time 3d echocardiography in mitral valve repair for replacement of chordae tendineae

Objective To investigate the surgical technique and outcomes of replacement of chordae tendineae in mitral valve repair,and evaluate the value of real-time three-di-mensional transesophageal echocardiography in the perioperative period. Methods Thirty-one patients with mitral valve prolapse underwent mitral valve repair using chordae tendineae replacement concomitant with implantation

3D打印模型结合CBL教学法在骨科住院医师规范化培训骨盆骨折教学中的应用

目的探讨3D打印模型结合CBL教学法在骨科住院医师规范化培训(简称住培)骨盆骨折教学中的应用效果。方法采用完全随机法将50名参加浙江省台州医院骨科住培的学员分为观察组和对照组。观察组采用3D模型打印结合CBL教学法,对照组采用传统教学法,通过临床知识理论考核、实践技能操作考试和调查问卷3个维度评价3D打印模型结合CBL教学法在骨盆骨折教学中的应用效果。结果观察组在临床知识理论考核、实践技能操作考试和满意度各方面均明显优于对照组(P<0.05)。结论3D打印模型结合CBL教学法在骨盆骨折教学中的应用有助于激发住院医师的学习兴趣,提高学习积极性和学习效率,有助于骨科专科知识的全面掌握和临床技能的综合提高,是一种切实有效、贴近临床实际的教学方法。

Real-time Simulation of Gas Based on Smoothed Particle Hydrodynamics

This paper extends the SPH method to gas simulation. The SPH （Smoothed Particles Hydrodynamics） method is the most popular method of flow simulation, which is widely used in large-scale liquid simulation. However, it is not found to apply to gas simulation, since those methods based on SPH can＇t be used in real-time simulation due to their enormous particles and huge computation. This paper proposes a method for gas simulation based on SPH with a small number of particles. Firstly, the method computes the position and density of each particle in each point-in-time, and outlines the shape of the simulated gas based on those particles. Secondly the method uses the grid technique to refine the shape with the diffusion of particle＇s density under the control of grid, and get more lifelike simulation result. Each grid will be assigned density according to the particles in it. The density determines the final appearance of the grid. For ensuring the natural transition of the color between adjacent grids, we give a diffuse process of density between these grids and assign appropriate values to vertexes of these grids. The experimental results show that the proposed method can give better gas simulation and meet the request of real-time.

Optimized Method for Real-time Texture Reconstruction with RGB-D Camera

With the appearance of RGB-D camera, the field of three-dimensional(3D) reconstruction receives more and more attention. In this paper, we present an optimization approach to produce high-quality textured 3D models based on the real-time 3D reconstruction system.The resulting models of real-time texture reconstruction often suffer from blurring, ghosting, and other artifacts.Our approach addresses this texture quality problem using blur detection and an optimized weight function. Experimental results demonstrate that our approach can improve the quality of textured 3D models by reducing the blur and ghosts on the model surface.

Determining Requirements for an Optimal Ad-Hoc Multicast Protocol in Mobile Health Care Training Systems

Nowadays, Health Care Training-based System (HCTS) is a vital component in the education and training of health care in 3D Virtual Environment (VE). The practice of HCTS continues to grow at rapid pace throughout all of the healthcare disciplines, however research in this field is still in its early stage. Increasingly, decision makers and developers look forward to offer more sophisticated, much larger, and more complex HCTS to serve the desired outcome and improve the quality and safety of patient care. Due to the rapidly increasing usage of personal mobile devices and the need of executing HCTS applications in environments that have no previous network infrastructure available, Mobile Health Care Training-based System (MHCTS) is an expected future trend. In such systems, medical staff will share and collaborate in a 3D virtual environment through their mobile devices in an ad-hoc network (MANET) in order to accomplish specific missions’ typically surgical emergency room. Users are organized into various groups (Radiologists, Maternity departments, and General surgery etc...), and need to be managed by a multicast scheme to save network bandwidth and offer immersive sense. MHCTS is sensitive to networking issues, since interactive 3D graphics requires additional load due to the use of mobile devices. Therefore, we need to emphasize on the importance and the improvement of multicast techniques for the effectiveness of MHCTS and the management of collaborative group interaction. Research so far has devoted little attention to the network communication protocols design of such systems which is crucial to preserve the sense of immersion for participating users. In this paper, we investigate the effect of multicast routing protocol in advancing the field of Health care Training-based System to the benefit of patient’s safety, and health care professional. Also, we address the issue of selecting a multicast protocol to provide the best performance for a particular e-health system at any time. Previous work has demonstrated that multicast operates at least as efficiently as traditional MAODV. A comprehensive analysis about various ad-hoc multicast routing protocols is proposed. The selection key factors for the right protocol for MHCTS applications were safety and robustness. To the best of our knowledge, this work will be the first initiative involving systematic literature reviews to identify a research gate for the use of multicast protocol in health care simulation learning community.

建筑工程制图3D建模研究

通过对建筑工程制图与CAD课程培养目标的分解,结合当前本课程的实际授课情况,构思出建筑工程制图与CAD课程能力构成及影响关系图。根据能力构成与影响关系图,给出了建筑工程制图与CAD课程的三大能力要素培养的具体实训措施,以识图为基础,制图为手段,最终实现3D建模。

眼眶爆裂性骨折修复手术模拟的眼眶3D打印模型和外科种植体模型的研究

目的设计并制作可用于眼眶爆裂性骨折修复手术临床与教学的3D眼眶模型。方法选取2016年11月至2017年2月在山东文登整骨医院眼科确诊的10例(10眼)眼眶下壁爆裂性骨折患者眼眶CT检查DICOM格式的原始CT数据。使用Mimics软件对二维CT图像依次进行阈值选取、区域增长、处理模具、多层编辑修饰等过程,最终获得完整的眼眶爆裂性骨折3D模型,通过3D打印机打印出患者的3D眼眶模型,测量各模型的具体大小,分别将模型与患者的眼眶解剖标志测量数据进行配对t检验。由高年资眼眶外科医师对打印的眼眶爆裂性骨折模型和外科种植体模型进行模拟手术操作。结果共有10例眼眶下壁爆裂性骨折患者,其中男5例(5眼)、女5例(5眼)。3D模型和外科种植体模型成功设计并打印。全部男性组和女性组眼眶爆裂性骨折3D打印模型与CT测量的眼眶数据基本相吻合,差异均无统计学意义(均为P>0.05)。由高年资眼眶外科医师在模拟手术室手术环境下向住院医师示范眼眶骨折修复术手术操作,3D打印的眼眶爆裂性骨折模型可成功用于模拟手术操作和教学示范。结论 3D打印的眼眶爆裂性骨折模型能够真实还原患者眼眶损伤情况和眼眶解剖细节,为医师提供了立体直观的术前设计的模型,对了解眼眶爆裂性骨折的波及范围和手术教学模拟具有积极意义。

A novel method for virtual clearance computation of high-speed train based on model integration and convex hull

The 3D clearance of a high-speed train(HST) is critical to ensure the safety of railway transportation. Many studies have been conducted on the inspection of the clearance profile in railway operation based on the vision system, but few researchers have focused on the computation of the 3D clearance in the design phase of an HST. This paper summarizes the virtual 3D clearance computation of an HST based on model integration and the convex hull method. First, both the aerodynamic and kinetic analysis models of the HST are constructed. The two models are then integrated according to the corresponding relationship map, and an array of transformation matrixes of the HST is created to drive the designed model simulating the physical railway motion. Furthermore, the convex hull method is adopted to compute the 3D envelope of the moving train. Finally, the Hausdorff metric is involved in the measurement of the minimum clearance model and the 3D envelope model. In addition, the color map of the Hausdorff distance is established to verify that the designed shape of the HST meets the national standards. This paper provides an effective method to accurately calculate the 3D clearance for the shape design of an HST, which greatly reduces the development cost by minimizing the physical prototype that must be built.

基于联合字典的3D图像去块效应方法

本文针对3D图像压缩过程产生的块效应,提出了一种基于联合字典的3D图像去块效应方法。该方法主要包括字典训练、字典联合和去块效应三个阶段。在字典训练阶段,采用字典学习方法分别训练得到过完备的彩色字典和深度字典;在字典联合阶段,根据测试图像的稀疏特性和构造的彩色和深度字典,求出对应的彩色与深度联合字典;在去块效应阶段,通过估计重构误差阈值,并根据联合字典对图像进行去块效应处理。实验结果表明,本文提出的方法能够有效地去除编码图像的块效应,且得到较高的虚拟视点绘制质量。

3-D Animation as Applied to the Solving of Coupling Relations in the 6-DOF Parallel Robot

How to solve the coupling relations in a 6 - DOF parallel robot quickly and accurately within the limits of realtime control is a critical problem. In traditional analytic method, the complicated mathemtical model must first be constructed and then solved by programming.Obviously, this method is not very practical. This paper,therefore, proposes a new way of approach with a new method using 3- D animation for the solving of coupling relations in the 6 - DOF parallel robot. This method is much simpler and its solving accuracy approaches that of the more complicated analytic method.

Reconstructing the 3D digital core with a fully convolutional neural network

In this paper, the complete process of constructing 3D digital core by fullconvolutional neural network is described carefully. A large number of sandstone computedtomography (CT) images are used as training input for a fully convolutional neural networkmodel. This model is used to reconstruct the three-dimensional (3D) digital core of Bereasandstone based on a small number of CT images. The Hamming distance together with theMinkowski functions for porosity, average volume specifi c surface area, average curvature,and connectivity of both the real core and the digital reconstruction are used to evaluate theaccuracy of the proposed method. The results show that the reconstruction achieved relativeerrors of 6.26%, 1.40%, 6.06%, and 4.91% for the four Minkowski functions and a Hammingdistance of 0.04479. This demonstrates that the proposed method can not only reconstructthe physical properties of real sandstone but can also restore the real characteristics of poredistribution in sandstone, is the ability to which is a new way to characterize the internalmicrostructure of rocks.

3D Slicer软件在神经外科规培生手术教学中的应用研究

目的评估3D Slicer软件在神经外科规培生手术教学中的作用。方法选择2021年4月-2022年3月笔者所在医院神经外科医学部创伤组及胶质瘤组进行外科(神经外科方向)住院医师规范化培训的44名学员为研究对象,随机分成两组(实验组和对照组),实验组采用3D Slicer软件进行手术教学,对照组采用传统方式进行手术教学。两组学生完成神经外科创伤组和胶质瘤组培训后,行临床理论内容考试及手术相关技能评估。数据算法采用SPSS 25.0统计学软件评估。结果传统培训及借助3D Slicer软件培训均有良好的培训效果;借助3D Slicer软件手术教学效果优于传统培训组,对比具有统计学意义(P<0.05);而且采用3D Slicer软件手术教学方式的规培医师的自我评价优于传统培训组,具有统计学意义(P<0.05)。结论3D Slicer软件可有效提升学生的学习兴趣,培养学生的空间思维能力,加速神经外科手术技能的学习。

Assessment of Cervical Screw Trajectory Using 3-Dimensional Software Planning

Objective: It is important and helpful for surgeons to understand the correlation between spinal anatomy and screw trajectory before surgery. We aimed to assess a simple technique using 3D imaging software available on the hospital intranet for visual and quantitative feedback to prepare surgeons for an appropriate entry point and safe trajectory when placing cervical screws. Methods: A total of 59 cervical screws were inserted from C1 to T1 in 12 consecutive patients using this technique. First, a single CT optimal slice was selected from 3D CT images of the cervical spine to determine the intervals of bilateral entry points and lateral angle. Next, this 3D image was rotated to the lateral angle. Finally, bone was cut out on the entry point using subtractive manipulation, which removed the core of the pedicle or lateral mass. Screw trajectory was indicated, and surgeons could assess the correlation between surface landmarks, spinal anatomy, and screw trajectory. Posterior cervical fusion was performed using fluoroscopy. Postoperative outcomes and incidence of complications were retrospectively assessed. Results: One perforation (1.4%) was identified on postoperative CT images. No vascular injuries occurred. Differences in the intended entry point location and lateral angle of the screw from actual postoperative values were 1.49 ± 1.23 mm and 5.46。 ± 4.46。, respectively. Conclusions: A novel 3D CT imaging assessment underwent in cervical screw fixation. This technique is easily accessible on the hospital intranet and provides training in cervical screw placement for fellows. Surgeons can simulate screw placement and share surgical strategy.

3D Vector Reconstruction of the Typical Cervical Vertebra from Anatomical Sections of Korean Visible Human at the Laboratory of Clinical and Digital Anatomy of Paris Descartes University

Aim: To carry out a 3D vector reconstruction of the typical cervical vertebra from anatomical sections of the “Korean Visible Human” for educational purposes. Material and Methods: The anatomical subject was a 33-year-old Korean man who died of leukemia. He was 164 cm tall and weighed 55 kg. This man donated his body to science. Her body was frozen and cut into several anatomical sections after an MRI and CT scan. These anatomical sections were made using a special saw called a 0.2 mm thick cryomacrotome. Thus 8100 cuts were obtained. Only the sections numbered 940 to 1200 were used for our study. A segmentation by manual contouring of the different parts of the typical cervical vertebra was made using the software Winsurf version 3.5 on a laptop PC running Windows 7 equipped with a Ram of 8 gigas. Results: Our 3D vector model of the typical cervical vertebra is easily manipulated using the Acrobat 3DPDF interface. Each part of the vertebra accessible in a menu can be displayed, hidden or made transparent, and 3D labels are available as well as educational menus for learning anatomy. Conclusion: This original work constitutes a remarkable educational tool for the anatomical study of the typical cervical vertebra and can also be used as a 3D atlas for simulation purposes for training in therapeutic gestures.