虚拟现实技术和全息投影技术在虚拟校园中的应用

现代计算机技术的不断进步,虚拟现实三维技术成为当前应用的重点.本文结合虚拟现实技术和全息投影的定义和区别,就其在虚拟校园中的应用进行探讨,从而为三维虚拟现实技术的普及和推广提供参考.     

Virtual reality is for real

Some current applications work in the computer-rendered environments known as virtual reality (VR) are examined. Caterpillar Inc., a manufacturer of earth-moving and construction equipment is using VR to assess interior visibility on new prototypes. The Big Three among US automobile makers are joining with a US Army vehicle center, United Technologies' automotive division, the University of Michigan, and a dozen other smaller companies to form a consortium for industrial VR. Boeings' new airliner, the 777, to be rolled out next year, is its first to be designed without the use of a full-scale physical mockup; VR was used instead. Military, medical, and entertainment applications of VR are growing     

Virtual reality treatment of flying phobia

Flying phobia (FP) might become a very incapacitating and disturbing problem in a person's social, working, and private areas. Psychological interventions based on exposure therapy have proved to be effective, but given the particular nature of this disorder they bear important limitations. Exposure therapy for FP might be excessively costly in terms of time, money, and efforts. Virtual reality (VR) overcomes these difficulties as different significant environments might be created, where the patient can interact with what he or she fears while in a totally safe and protected environment, the therapist's consulting room. This paper intends, on one hand, to show the different scenarios designed by our team for the VR treatment of FP, and on the other, to present the first results supporting the effectiveness of this new tool for the treatment of FP in a multiple baseline study.     

虚拟现实及增强现实技术在工业设计中的应用

工业设计技术已日益成为产品创新、价值增值过程中重要的手段。由于现有技术支撑手段的局限,传统工业设计过程中反复叠代修改的“设计-快速原形（CAD〉RP）”循环制约了设计师发挥的空间。虚拟现实及增强现实技术的应用可以为设计师提供一个自然、辜观、交互的环境表达设计思想。虽然已有大量的文献描述混合现实技术的进展及其在制造业的应用,但还鲜有专门着重于工业设计这一重要的领域。本文从一个工业设计工程师的角度阐述了混合现实技术在工业设计中的应用,尤其着重于在增强现实环境下的三维空间设计、数字样机和虚拟装配,并与现有的设计方式进行了比较。     

基于B样条辅助虚拟现实室内设计

为了获得理想的虚拟现实室内设计效果,提出基于B样条辅助虚拟现实室内设计方法。首先采用3DMAX建立基本体绘制室内家具模型,利用扩展基本体L-形墙、C-形墙构建个性化墙体,并利用Maya软件设计虚拟现实室内特效;然后以渲染完成的室内模型为前提,采用多视窗交互方法定义曲线以及直线相机路径,设计室内展示动画,利用外部播放器程序播放;最后采用B样条基的形式对虚拟现实室内设计效果进行修复,并加入一阶左导数与右导数相等的约束条件,使得最终效果是表面连续光滑,不会让人产生突兀的感觉,并通过仿真模拟实验验证其性能。结果表明,所提方法可获得理想的虚拟现实室内设计可视化效果,生动地展示了室内设计结构、质感、造型等信息,克服了当前虚拟现实室内设计方法存在的缺陷。     

虚拟现实技术的应用现状及发展

介绍了虚拟现实技术的构成和技术特点，回顾了虚拟现实技术的发展历史和研究背景，分析了虚拟现实系统的应用现状，重点论述了分布式虚拟现实系统的应用和发展前景。     

虚拟现实系统中水体绘制技术的研究与应用

在虚拟现实系统实现过程中,水体的模拟是非常重要的部分。本文通过对水体特点进行剖析,比较、借鉴总结大量国内外研究成果及文献,深入地分析和研究了不同场景中的水体实时模拟绘制方法,提出了具有较高绘制效率和视觉效果的能够在PC机上实现的不同水体模型的绘制方法。     

虚拟现实系统中水体绘制技术的研究与应用

在虚拟现实系统实现过程中,水体的模拟是非常重要的部分。本文通过对水体特点进行剖析,比较、借鉴总结大量国内外研究成果及文献,深入地分析和研究了不同场景中的水体实时模拟绘制方法,提出了具有较高绘制效率和视觉效果的能够在PC机上实现的不同水体模型的绘制方法。     

基于虚拟现实的森林公园景观的节能设计

针对传统方法存在节能效果差的问题,提出基于虚拟现实的森林公园景观的节能设计方案。对数据采集系统进行了节能优化设计,数据采集系统中的数据采集器是利用视觉影像的反衬图像的方法进行数据采集的,因此在使用过程中消耗电量极大,故对数据采集器以及控制电力系统进行了优化设计,这样能够有效地减少能源的消耗。在虚拟影像建立的过程中会使用边缘关联算子进行相关计算,实现电能的低量消耗。实验结果表明,采用基于虚拟现实的森林公园景观的节能效果较好,具有一定的优势。     

基于虚拟现实的人机交互下协同式产品外观设计

为了解决当前产品外观设计方法很难完全模拟人类智能对产品外观进行设计的问题,提出一种新的基于虚拟现实的人机交互下协同式产品外观设计方法,给出虚拟现实设计环境总体结构,在虚拟环境下,计算机主要负责对符合约束的方案进行求解,而设计者主要负责确定产品外观设计过程中的变量、约束条件及设计目标等,令二者协同设计产品外观,获取最佳设计方案。为了更好地实现人机交互,对设计者知识描述进行转换,依据创新元对设计者决策信息进行分类、描述以及保存。通过再次转换将参数确定问题变成基本参数描述问题,以确定设计参数。实验结果表明,所提方法鲁棒性和多样性高,且设计的产品外观普遍评价较高。     

Virtual knowledge: bistable reality and the solution of ill-definedproblems

Dynamic behavior is enacted from static observations, but as experience is reconstructed with concepts, mutual exclusivity replaces correspondence between the factors of action and observation. This bistable reality generates incommensurable world views between groups, which constrain measurement and give rise to a tension that enables change but also results in misleading accounts, as if behavior were in response to virtual knowledge. In the form of independent scientific peer reviews at a Department of Energy site, tension was applied to improve practices of science in the field. Implications for a physics of interaction are addressed     

虚拟现实与高中通用技术相结合可行性试探

随着技术的进步和科学的发展,虚拟现实技术越来越贴近人们的日常生活,将虚拟现实技术应用于高中通用技术课程的教育教学,将有助于解决目前通用技术课程面对的一些问题。基于这样的现状,将虚拟现实技术与通用技术课程相结合进行一些探究。     

基于移动边缘计算的虚拟现实压缩与传输系统

针对基于云服务的虚拟现实对数据传输速率的高要求以及对传输时延的敏感性问题,提出并设计了基于移动边缘计算技术的云VR系统方案,主要包括基于视点的VR处理和混合数模传输优化。首先采用基于金字塔投影的用户视点感知动态推流方法实现基于视点的VR处理;然后引入混合数模技术对传输进行优化改进,并给出了启发式的资源分配优化算法;最后在长期演进(LTE)系统的基础上改造基站协议栈,融入移动边缘计算技术,实现了完整的移动边缘云VR系统。实验结果表明,与已有方案相比,所提方案能够实现更加稳健高效的传输,达到更好的VR用户体验。     

基于三维重建的虚拟现实类鸟飞行系统

随着虚拟现实(virtual reality, VR)技术的飞速发展,各种应用层出不穷。然而目前大多应用仅限于定点的静态全景展示及游览,无法利用VR化不可能为可能的优越性。本文提出了一种融合VR技术与三维重建算法的类鸟飞行交互模拟系统。该系统搭建了结构稳定的硬件控制平台用以改变实际姿态,同时通过软件仿真了虚拟环境中鸟类的飞行,结合硬件驱动及软件模拟实现了深层次的飞行模拟。现有的虚拟环境大多通过人工建模、激光扫描仪或无人机(unmanned aerial vehicle, UAV)航拍构造,其中建模存在费时费力的缺点,激光扫描仪则无法适应大规模重建,而UAV成本高昂且需专业培训。本文引入了基于图像分簇的PMVS (patch based multi-view stereopesis)算法,只需输入特定场景的图片即可利用计算机自动恢复出三维结构,不仅快速而且可对任意场景重构。使用户在足不出户的情况下即可在世界各地体验飞行,为旅游事业及VR产业提供了一种新的可能。     

虚拟现实技术下的工业产品设计CAD三维造型系统

为了将虚拟现实(VR)技术与传统CAD工业产品建模进行有效结合,设计一种基于虚拟现实技术的机械产品CAD三维造型系统,可以有效解决传统产品开发所面临的问题。采用非均匀有理B样条曲线构造实体几何模型,并对立体视觉模型的投影进行变换设计,从而在有限硬件条件下减少计算所需的时间。给出虚拟环境系统的具体软硬件参数。开发语言采用Visual C#,并采用工业级模拟开发软件Vega实现CAD数据转换。系统运行结果显示,设计系统能够有效实现机械产品零部件的辅助设计,节省了设计研发时间。     

Virtual reality adoption during the COVID-19 pandemic: A uses and gratifications perspective

The coronavirus disease 2019 (COVID-19) pandemic has impacted all aspects of people's lives, including how we work, play, learn, exercise, and socialize. Virtual reality (VR) technology has the potential to mitigate many of the challenges brought about by the pandemic, which has spurred increased adoption. However, relatively low adoption overall and limited software still restrict the power of VR to address COVID-19 difficulties effectively. This study examines how the perceived impacts of COVID-19 might lead to different VR uses and gratifications and device ownership / variability. Furthermore, we investigate the importance of social interactivity within VR for increasing adoption intentions.We surveyed 298 Amazon Mechanical Turk users during the Fall of 2020. Results indicate that the pandemic's perceived impacts influenced the likelihood of acquiring VR for education, tourism, and work. For VR ownership and variability, those who purchased VR during the pandemic were more likely to report buying it for work. Those with access to high-end VR hardware were more likely to report a broader range of uses, including socializing, health, and telemedicine. Validating the importance of various applications during the pandemic, we found that the desire for social interactivity mediates the impacts of COVID-19 on future adoption intentions. Theoretically, we propose several gratifications sought via the use of VR during the pandemic. Practically, we discuss recommendations for future VR research, marketing, and software design.     

A statistical model for interpreting computerized dynamic posturography data

Computerized dynamic posturography (CDP) is widely used for assessment of altered balance control. CDP trials are quantified using the equilibrium score (ES), which ranges from zero to 100, as a decreasing function of peak sway angle. The problem of how best to model and analyze ESs from a controlled study is considered. The ES often exhibits a skewed distribution in repeated trials, which can lead to incorrect inference when applying standard regression or analysis of variance models. Furthermore, CDP trials are terminated when a patient loses balance. In these situations, the ES is not observable, but is assigned the lowest possible score--zero. As a result, the response variable has a mixed discrete-continuous distribution, further compromising inference obtained by standard statistical methods. Here, we develop alternative methodology for analyzing ESs under a stochastic model extending the ES to a continuous latent random variable that always exists, but is unobserved in the event of a fall. Loss of balance occurs conditionally, with probability depending on the realized latent ES. After fitting the model by a form of quasi-maximum-likelihood, one may perform statistical inference to assess the effects of explanatory variables. An example is provided, using data from the NIH/NIA Baltimore Longitudinal Study on Aging.     

Innovation rooted in reality

The world of telecoms has changed almost beyond recognition since the 1970s. Phil Holmes, BTexact's chief technology officer, talks of technology mini-revolutions. There are two elements to Holmes's work. One is to look at what's going on within BTexact and communicate that to the rest of the group and the outside world. The other is to keep abreast of what's happening elsewhere and spot the areas worth pursuing. When BT enter the market they tend to provide a service of great geographical coverage, certainly at a competitive price, and probably with greater opportunity to bundle services together. Supporting new services means that old equipment has to be replaced. Examples of technology innovations discussed in the article include multi-protocol label switching and broadband.