Chemical simulation teaching system based on virtual reality and gesture interaction

Background Most existing chemical experiment teaching systems lack solid immersive experiences,making it difficult to engage students.To address these challenges,we propose a chemical simulation teaching system based on virtual reality and gesture interaction.Methods The parameters of the models were obtained through actual investigation,whereby Blender and 3DS MAX were used to model and import these parameters into a physics engine.By establishing an interface for the physics engine,gesture interaction hardware,and virtual reality(VR)helmet,a highly realistic chemical experiment environment was created.Using code script logic,particle systems,as well as other systems,chemical phenomena were simulated.Furthermore,we created an online teaching platform using streaming media and databases to address the problems of distance teaching.Results The proposed system was evaluated against two mainstream products in the market.In the experiments,the proposed system outperformed the other products in terms of fidelity and practicality.Conclusions The proposed system which offers realistic simulations and practicability,can help improve the high school chemistry experimental education.

Research on key techniques of virtual reality applied in mining industry

Based on the applications of virtual reality technology in many fields, introducedthe virtual reality technical basic concept, structure type, related technique development,etc., tallied up applications of virtual reality technique in the present mining industry, inquired into core techniques related software and hardware, especially the optimization inthe setup of various 3D models technique, and carried out a virtual scene to travel extensively in real-time by stereoscopic manifestation technique and so on. Then it broughtforward the solution of virtual reality technique with software and hardware to the miningindustry that can satisfy the demand of different aspects and levers. Finally, it show a fineprospect of virtual reality technique applied in the mining industry.

An improved social force model (ISFM)-based crowd evacuation simulation method in virtual reality with a subway fire as a case study

Crowd evacuation simulation using virtual reality(VR)is significant for digital emergency response construction.However,existing evacuation simulation studies suffer from poor adaptation to complex environments,inefficient evacuations,and poor simulation effects and do not fully consider the impacts of specific disaster environments on crowd evacuation.To more realistically express the crowd evacuation results obtained under the influence offire environments and the subjective consciousness of pedestrians in subway stations,we designed a dynamic pedestrian evacuation path planning method under multiple constraints,analysed the influences of an‘environmental role’and a‘subjective initiative’on crowd evacuation,established an improved social force model(ISFM)-based crowd evacuation simulation method in VR,developed a prototype system and conducted experimental analyses.The experimental results show that the crowd evacuation time of the ISFM is affected by the disaster severity.In simulation experiments without disaster scenarios,the improved model’s crowd evacuation efficiency improved by averages of 12.53%and 15.37%over the commercial Pathfinder software and the original social force model,respectively.The method described herein can effectively support real-time VR crowd evacuation simulation under multiexit and multifloor conditions and can provide technical support for emergency evacuation learning and management decision analyses involving subwayfires.

Geomorphology visualization modeling and tidal current virtual reality for coastal ocean

The new technology of geomorphology visualization modeling and virtual reality for tidal current numerical simulation are the important methods utilized in coastal ocean research. In the project of studying the evolutionary trend of radial sand ridges in South Yellow Sea of China, this method becomes the key to reveal the correlation betweenthe seabed topography and the hydrodynamic factor——tidal current. It is proved that using the geomorphology visualization and tidal virtual reality techniques, oceanog-raphers might be able to intuitively discover the interaction pattern of sand ridges and tidal current, predicting the development of sand ridge stability in the future. Furthermore,a prototypic software system——VROcean was designed andimplemented to examine the performance of the new visualization technology on the contrast to traditional methods.

WEB-BASED VIRTUAL CNC MACHINE MODELING AND OPERATION

A CNC simulation system based on intemet for operation training of manufacturing facility and manufacturing process simulation is proposed. Firstly, the system framework and a rapid modeling method of CNC machine tool are studied under the virtual environment based on PolyTrans and CAD software. Then, a new method is proposed to enhance and expand the interactive ability of virtual reality modeling language（VRML） by attaining communication among VRML, JavaApplet, JavaScript and Html so as to realize the virtual operation for CNC machine tool. Moreover, the algorithm of material removed simulation based on VRML Z-map is presented. The advantages of this algorithm include less memory requirement and much higher computation. Lastly, the CNC milling machine is taken as an illustrative example for the prototype development in order to validate the feasibility of the proposed approach.

基于虚拟现实的虚拟仿真建模及渲染技术

虚拟现实技术能够创造出逼真的虚拟环境,为能够更加快速地建立模型,该文结合相关工具和Unity3D平台开发仿真建模及渲染技术。通过工具收集真实地形的数据,然后进行相关的数据处理并生成数据集合。通过使用Unity3D中地形工具进行数据读取和快速制作三维场景模型,为提高模型的渲染逼真度使用高清渲染管线对场景模型进行光照等渲染处理。通过对该技术的研究,该技术能够使三维场景的逼真度提高及渲染程度非常好,模型细节也能观察,同时该技术也能被运用到毁伤评估仿真、虚拟训练等方面。

基于生成性学习理论的幼儿保育沉浸式虚拟仿真实训设计研究

利用虚拟现实技术进行幼儿保育典型工作环节的虚拟实训,是一项在学前教育教学领域利用虚拟现实技术的模拟性和沉浸性来开展幼儿园生活保育实训的新型实践模式,使学习者能在虚拟的幼儿园环境中,以虚拟实训的方式完成幼儿保育工作的实操实训,目前鲜有相关研究。根据生成性学习理论、沉浸理论,构建基于VR环境的沉浸式虚拟仿真实训生成性学习模型,有利于沉浸式虚拟现实仿真实训在学前教育领域的推广。

土壤学互融互补混合式智慧教学模式改革成效

土壤学是理论系统性高和应用实践性强的重要专业基础课。探索基于网络信息技术的土壤学线上线下混合式教学的新型模式,对于全面推进新时代一流专业建设及一流专业人才培养至关重要。综合应用文献查阅法、问卷调查法和经验总结法,以优化教学内容和变革教学策略为途径,构建土壤学“互融互补混合式智慧教学模式”。这一新型教学模式包含“思政元素、专业应用、学科前沿、行业发展”的四元融合知识体系、“课前-课中-课后”三环渐进混合式智慧教学方式、“一、二课堂互补,现实虚拟互补”的二维互补实践创新能力培养体系。模式实施以来有力地提升土壤学“一流课程”“思政示范课”建设质效,以及富有“三农”情怀、能“识土-辨土-用土-改土”的新农科复合型高级人才质量,为其他传统专业课改革提供借鉴。

基于虚拟现实的森林灭火指挥训练系统研究

森林消防队伍日常训练和考评主要以森林灭火应急预案进行实装演练,针对训练中成本高、环境受限、内容不足等问题,迫切需要采用虚拟现实、人工智能等先进技术实现森林灭火指挥训练与考评系统。本文自主研发了一套基于定制化的Unity3D渲染引擎的虚拟仿真训练教学考评系统。对比国外主流虚拟仿真软件,本系统中场景细节更逼真,能进行实景虚拟仿真训练,更加贴近灭火实战;同时系统具有自主可控性、可扩展性,为用户提供简单编辑方式,支持火环境设计制作等森林消防专业应用逻辑。本文研究结果对于探索建立规范化、信息化森林灭火指挥员训练考评体系具有重要的现实意义。

虚拟仿真技术在广播编导中的应用

虚拟仿真技术的应用丰富了广播电视编导领域的创作手段,提升了作品的视听体验和创作效率。阐述虚拟仿真技术的定义、基本原理和主要特点,分析了虚拟仿真技术的实现过程及其在广播电视编导领域的具体应用。

Web-Based Interactive Simulation of Weft Knitted Fabric

In order to realize parametric simulation of three-dimensional(3D)fabric structure based on web,a 3D model describing a plain knitted fabric,in which the cross-section of the yarn is circular shape and the path of the yarn is cubic B-spline curve,is proposed in this paper.With this model,the 3D simulation of the loop and of the basic structures of the knitted fabric is realized by using Virtual Reality Modeling Language(VRML).The virtual simulation scene is suitable for network transmission with freely available VRML browsers and can be translated,scaled and rotated quite arbitrarily.By using Java and External Authoring Interface(EAI)technology,the web-based interactive simulation platform of weft knitted fabric is established.The user can input type of structures,basic fabric parameters,and yarn colors interactively to obtain a more realistic simulation result in real-time.A new approach is provided to imitate the knitted fabric 3D appearance on network.

以作战仿真推动军事训练实战化

仿真是验证新型作战概念、检验装备水平、提升训练效果的有效手段。为实现以作战仿真手段提升部队训练水平,基于军事训练实战化背景,剖析作战仿真技术本质,梳理作战仿真所涉及的关键技术,根据当前的科技发展水平,分析作战仿真的发展趋势,从树立“实”的理念、注重统筹规划、加强条件建设、创新训练模式等4个方面提出建设发展军事模拟训练的思考建议。

基于虚拟现实的施工进度三维可视化模拟系统

当前建筑施工进度多使用二维系统进行可视化显示,并且在可视化模拟过程中,未计算各工序的施工工期,导致施工进度模拟效果较差。为此,设计基于虚拟现实技术的施工进度三维可视化模拟系统,通过功能模块层、业务逻辑层和应用系统层构建总体架构。其中,功能模块层由施工监测图像采集模块、图层管理模块、工序排布与工期估算模块,以及虚拟现实场景可视化展示模块组成。通过鱼眼摄像头采集施工监测图像,采用小波阈值方法对采集到的施工监测图像进行去噪处理,根据图像预处理结果,计算出各工序的施工工期,获取施工进度,构建三维虚拟展示场景模型,对施工进度进行虚拟现实场景可视化展示。实验结果表明,该系统进行高层建筑工程施工进度三维可视化模拟的精度较高,模拟时间较短,且施工进度的效率较高。

融合Unity3D和混合现实的虚拟场馆IDS

研究融合Unity3D和混合现实的虚拟场馆交互展示仿真方法,实现虚拟场馆的交互展示,提升用户交互体验效果。上述方法利用基础层为交互展示提供硬件设备;数据层通过调用硬件设备采集虚拟场馆数据;业务逻辑层中利用混合现实技术的KinectFusion算法,结合采集的数据,建立虚拟场馆三维模型,Unity3D软件内导入模型,依据模型信息设计基于寻路算法的交互方式,自动搜索交互展示路径,避免发生碰撞;应用层通过移动与旋转等操作,为用户提供场景切换与漫游等功能。仿真结果证明:上述方法可有效建立虚拟场馆三维模型,实现虚拟场馆的交互展示,为用户提供身临其境的交互体验;上述方法可有效搜索交互展示路径,精准避开障碍物。

A novel progress of leg tissue properties modeling based on biomechanics

To describe strategies for addressing technical aspects of computational modeling of leg tissue with the finite element （FE） method, a patient＇s leg sample was selected and scanned by CT at the direction parallel to the Frankfort Horizontal plane. A three-dimensional （3D） finite element model of the human leg was developed using the actual geometry of the leg skeleton and soft tissues, which were obtained from 3D reconstruction of CT images. All joints were defined as contact surfaces, which allow relative articulating movement. The major ligaments were simulated using tension-only truss elements by connecting the corresponding attachment points on the bone surfaces. The bony and ligamentous structures were embedded in a volume of soft tissues. The muscles were defined as non-linear viscoelastic material, and the skin, ligaments and tendons were defined as hyperelastic, while the bony structures were assumed to be linearly elastic. The muhilayer FEM model containing thighbone, tibia, fibula, kneecap, soft tissue was formed after meshing. Diverse forces were imposed on the FEM model. The results show that the multilayer FEM model can represent tissue deformation more accurately.

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.

基于“互联网+”的运动医学临床教学探究

网络时代,随着信息技术的迅猛发展,人们对健康的关注日益增加。在传统医学模式下,单一的以药、医、护为主的教学内容已不能满足学生在知识掌握、学习能力提升等方面的需要。“互联网+”教育理念下的教学方式将打破时空限制,不再拘泥于课堂教学,而是通过网络进行课外辅导及互动交流,实现学生自主、个性化学习,自我诊断,综合素质等多方面发展。文章以将“互联网+”教学模式应用于运动医学临床教学为主线,分别阐述了医学三维图像、医学生物力学建模仿真技术、医学虚拟现实技术等几种“互联网+”教学模式在临床教学中的应用及对传统教学模式进行创新教育的有效性,为临床教学模式创新提供参考。

Digital Factory-A Technology Show Case for Teaching and Research in Digital Manufacturing

With the advancing digital technology and information tools in networking the core of manufacturing activities has shifted from the physical production of goods to the systematic processing of knowledge.The competitiveness of tomorrow’s manufacturing enterprise lies in the operation of such digital factory in parallel with the physical one.This change in manufacturing in the digital age is taking place not only in Hong Kong but worldwide.This paper describes the development of establishing a digital factory laboratory in the Department of Industrial and Systems Engineering of The Hong Kong Polytechnic University.The Digital Factory is a focus for teaching research and technology transfer in the area of digital manufacturing.The paper also describes an application case of virtual manufacturing in which computer simulation models of a production line of an AC motor are developed for investigation.

Research and application of the virtual simulation system teaching method in NC machining course

Virtual simulation technology has become one of the most popular technologies in the field of engineering education after the multimedia information technology in recent years.This paper,based on the comprehensive integrated simulation and verification module of UG NX software,describes and discusses a novel virtual simulation system teaching(VSST)for numerically controlled machining to support the student engineering training to achieve the theoretical knowledge and practical techniques in numerically controlled machining.The findings of a study designed to evaluate the impact of VSST for the development of numerically controlled machining course are presented here.In addition,analysis of the follow-up surveys indicates that the VSST method enables to provide the concrete experience of interaction between the students and the simulation environment and to further stimulate students’interest in learning,so that the students who used VSST achieve significantly higher results than their co-workers.

基于VR的采摘机器人仿真试验研究

针对采摘机器人精度和识别能力较差的问题,基于VR技术对采摘机器人进行试验研究。采摘机器人主要由PC控制中心、虚拟现实系统、传感器系统、通信系统和执行器系统等组成。为了实现快速、精准采摘,采用虚拟现实环境建模。首先,确定真实环境和虚拟环境的相对位置,然后采用神经网络模型进行非特定模型的参数辨识,最终确定虚拟环境模型。为了验证该采摘机器人的性能,对其进行定位精度试验和采摘试验,结果表明:采摘机器人的定位精度较高,采摘效果良好,采摘过程中可成功避障。