Background Due to the restriction of display mode,in most of the virtual reality systems with multiple people in the same physical space,the program renders the scene based on the position and perspective of the one u...Background Due to the restriction of display mode,in most of the virtual reality systems with multiple people in the same physical space,the program renders the scene based on the position and perspective of the one user,so that other users just see the same scene,resulting in vision disorder.Methods To improve experience of multi-user co-located collaboration,in this study,we propose a fire drill system supporting co-located collaboration,in which three co-located users can collaborate to complete the virtual firefighting mission.Firstly,with multi-view stereoscopic projective display technology and ultra wideband(UWB)technology,co-located users can roam independently and watch virtual scenes through the correct perspective view based on their own position by wearing dedicated shutter glasses,thus carrying out different virtual tasks,which improves the flexibility of co-located collaboration.Secondly,we design simulated firefighting water-gun using the micro-electromechanical system sensor,through which users can interact with virtual environment,and thus provide a better interactive experience.Finally,we develop a workbench including a holographic display module and multi touch operation module for virtual scene assembly and virtual environment control.Results The controller can use the workbench to adjust the virtual layout in real time,and control the virtual task process to increase the flexibility and playability of system.Conclusions Our work can be employed in a wide range of related virtual reality applications.展开更多
文摘目的:探究左侧乳腺癌保乳术后基于内缘切线拉弧的容积调强放疗(volumetric modulated arc therapy,VMAT)与常规切线拉弧的VMAT的剂量学差异,挖掘VMAT技术在乳腺癌保乳术后更大的获益,为乳腺癌保乳术后VMAT计划设计提供更多的参考和数据支持。方法:回顾性选取30例左侧乳腺癌保乳术后行调强放疗的患者,为每位患者分别设计常规切线拉弧(conventional tangential arc,CTA)和内缘切线拉弧(inner edge tangentialarc,IETA)两组VMAT计划。统计两组计划的靶区适形度指数(conformity index,CI)、均匀性指数(homogeneity index,HI)、机器跳数、危及器官受照剂量等数据,并进行数据分析。结果:靶区适形性指数(CI)CTA组和IETA组分别为0.86±0.02和0.87±0.02(P<0.05),D_(98)、D_(50)、D_(2)、均匀性指数(HI)和机器跳数均无明显差异(P>0.05);IETA组危及器官左肺V_(5)、V_(10)、V_(20)、V_(30)、V_(40)、D_(mean),右肺V_(5)、D_(mean),心脏V_(5)、V_(10)、V_(20)、D_(mean)均低于CTA组(P<0.05),其中左肺V_(5)和V_(20)CTA组和IETA组分别为37.18±7.18 vs 34.32±6.43、11.00±2.40 vs 9.65±2.17;右肺D_(mean)和心脏D_(mean)CTA组和IETA组分别为302.26±42.78 vs 273.50±26.62,479.30±60.08 vs 442.39±140.92,IETA组均低于CTA组;两组右侧乳腺D_(mean)相差甚微(P>0.05)。结论:两种计划均能满足临床要求,但IETA的VMAT靶区适形度明显提高,同时还显著降低了左肺、右肺、心脏和脊髓的受量。因此,左侧乳腺癌保乳术后基于内缘切线拉弧VMAT可实现靶区和危及器官更大的获益,值得推荐。
基金National Key Research and Development Program of China(2018YFC0831003)Key R&D project of Shandong Province(2016GGX106001).
文摘Background Due to the restriction of display mode,in most of the virtual reality systems with multiple people in the same physical space,the program renders the scene based on the position and perspective of the one user,so that other users just see the same scene,resulting in vision disorder.Methods To improve experience of multi-user co-located collaboration,in this study,we propose a fire drill system supporting co-located collaboration,in which three co-located users can collaborate to complete the virtual firefighting mission.Firstly,with multi-view stereoscopic projective display technology and ultra wideband(UWB)technology,co-located users can roam independently and watch virtual scenes through the correct perspective view based on their own position by wearing dedicated shutter glasses,thus carrying out different virtual tasks,which improves the flexibility of co-located collaboration.Secondly,we design simulated firefighting water-gun using the micro-electromechanical system sensor,through which users can interact with virtual environment,and thus provide a better interactive experience.Finally,we develop a workbench including a holographic display module and multi touch operation module for virtual scene assembly and virtual environment control.Results The controller can use the workbench to adjust the virtual layout in real time,and control the virtual task process to increase the flexibility and playability of system.Conclusions Our work can be employed in a wide range of related virtual reality applications.