Redirected jumping in virtual scenes with alleys

Background The redirected jumping(RDJ)technique is a new locomotion method that saves physical tracking area and enhances the body movement experience of users in virtual reality.In a previous study,the range of imperceptible manipulation gains in RDJ was discussed in an empty virtual environment(VE).Methods In this study,we conducted three tasks to investigate the influence of alley width on the detection threshold of jump redirection in a VE.Results The results demonstrated that the imperceptible distance gain range in RDJ was not associated with the width of the alleys.The imperceptible height and rotation gain ranges in RDJ are related to the width of the alleys.Conclusions We preliminarily summarized the relationship between the occlusion distance and manipulation range of the three gains in a complex environment.Simultaneously,the guiding principle for choosing three gains in RDJ according to the occlusion distance in a complex environment is provided.

Effects of virtual environment and self-representations on perception and physical performance in redirected jumping

Background Redirected jumping(RDJ)allows users to explore virtual environments(VEs)naturally by scaling a small real-world jump to a larger virtual jump with virtual camera motion manipulation,thereby addressing the problem of limited physical space in VR applications.Previous RDJ studies have mainly focused on detection threshold estimation.However,the effect VE or self representation(SR)has on the perception or performance of RDJs remains unclear.Methods In this paper,we report experiments to measure the perception(detection thresholds for gains,presence,embodiment,intrinsic motivation,and cybersickness)and physical performance(heart rate intensity,preparation time,and actual jumping distance)of redirected forward jumping under six different combinations of VE(low and high visual richness)and SRs(invisible,shoes,and human-like).Results Our results indicated that the detection threshold ranges for horizontal translation gains were significantly smaller in the VE with high rather than low visual richness.When different SRs were applied,our results did not suggest significant differences in detection thresholds,but it did report longer actual jumping distances in the invisible body case compared with the other two SRs.In the high visual richness VE,the preparation time for jumping with a human-like avatar was significantly longer than that with other SRs.Finally,some correlations were found between perception and physical performance measures.Conclusions All these findings suggest that both VE and SRs influence users'perception and performance in RDJ and must be considered when designing locomotion techniques.

Percutaneous Mesh Expansion and Fixation at the Retro-Rectus Plane without Stabs by Using Redirecting Suture Hook in Midline Hernias Repair

Background: Mesh expansion and fixation at retro-rectus plane through multiples stabs produces good results. But these stabs cause cosmetic disorders for the patients and doctors. So, we find some modification to do this procedure without these stabbing wounds in midline hernial repair. Patients and methods: This technique was used to fix the mesh at retro-rectus plane in 50 patients suffering from midline hernias, from January 2008 through January 2010 at Zagazig university Hospital, Egypt. Laparotomy incision was done over the hernial sac or at old incision;the contents were then released and reduced into peritoneal cavity without much subcutaneous dissection. The suitable sheet of polypropylene mesh to cover the hernial defect and any weak area was prepared and fixed at retro-rectus plane percutaneously without stabbing wounds by using redirecting suture hook. The mean period of follow up was 26 months. Results: There was no recurrence during the period of follow up. Five patients developed subcutaneous bluish discoloration at the site of some stitches, which disappear within two weeks with conservative treatment. Conclusion: Percutaneous mesh expansion and fixation at retro-rectus plane by using redirecting suture hook procedure has good results in recurrence rate and cosmetic appearance.

基于WebRedirection的图书馆无线网络认证的实现

文章基于网页重定向技术，结合图书馆业务系统Interlib和接入控制网关ACG，搭建了具有行业特色的认证服务器，在对我馆现有网络做尽可能少的变动下，以低成本实现了电子阅览室等公共区域无线网络的实名认证和有线无线网络的统一管理与审计，达到了理想的效果。

Locomotion perception and redirection

Locomotion is a fundamental interaction technique that allows free navigation in virtual scenes.A large body of literature has demonstrated that natural locomotion experience can significantly improve the sense of presence and help users achieve better performance in tasks such as searching and training.In the upcoming metaverse era,locomotion will play a critical role in the success of large-scale interactive applications.Perception and redirection are two tightly connected problems in virtual locomotion.Given a limited physical condition and a target virtual scene,how to make the perceived locomotion as natural as possible,and further unknowingly redirect the user in the physical world is an open question.In this special issue,we have selected five papers that provide their latest updates for research problems of view control,virtual jumping,climbing,and searching.

UIT Redirect-on-Write快照技术助力电信级数据容灾

介绍UIT独特的逻辑快照技术,用指针重定向的方式减少每次磁盘做快照时的读写,及减少做快照的所需的磁盘容量。并且生成多个不同时间点的数据版本。另介绍UIT逻辑快照在电信级容灾项目里面的使用。

Stepping forward:T-cell redirecting bispecific antibodies in cancer therapy

T cell-redirecting bispecific antibodies are specifically designed to bind to tumor-associated antigens,thereby engaging with CD3 on the T cell receptor.This linkage between tumor cells and T cells actively triggers T cell activation and initiates targeted killing of the identified tumor cells.These antibodies have emerged as one of the most promising avenues within tumor immunotherapy.However,despite success in treating hematological malignancies,significant advancements in solid tumors have yet to be explored.In this review,we aim to address the critical challenges associated with T cellredirecting bispecific antibodies and explore novel strategies to overcome these obstacles,with the ultimate goal of expanding the application of this therapy to include solid tumors.

反应中断再定向干预孤独症谱系障碍儿童刻板语言的效果:Scoping综述

目的对运用反应中断再定向干预孤独症谱系障碍(ASD)儿童刻板语言的研究进行Scoping综述分析。方法检索EBSCO、PubMed、Web of Science、中国知网、万方数据库中使用反应中断再定向的方法对ASD儿童的刻板语言进行干预的相关文献,提取文献中的数据信息对其进行Scoping综述。结果最终纳入16篇英文文献,均采用单一受试时间序列研究设计。共涉及41例ASD儿童,出现刻板语言行为的ASD儿童基本语言功能有显著差异。刻板语言表现为语言和非语言声音两种形式。多数研究使用实验功能评价来确认刻板语言的功能,绝大多数ASD儿童刻板语言的功能为自动强化。实验功能评价以Iwata等的范式为主,其他评价范式在此范式基础上进行一定的改变,使操作更简洁。反应中断再定向常在个别化的情境中进行,少数研究尝试在特殊教育班级中进行。因刻板语言和其他行为的障碍程度不同,干预时长和频率差异较大。通过比较传统反应中断再定向与其变形程序对刻板语言的改善效果发现,改变再定向任务内容,减少再定向任务数量及不同执行时长对其效果没有显著影响。反应中断再定向与匹配刺激的非后效强化、反应代价、语言操作训练、药物治疗等方法进行比较的结果认为,反应中断再定向及其他方法(除药物治疗)都可以在一定程度上减少ASD儿童的刻板语言,并促进适当行为的出现,但反应中断再定向与匹配刺激、反应代价等其他方法共同使用会更有效。结论伴有刻板语言的ASD儿童具有不同功能性语言表现,其刻板语言表现形式包括语言和非语言的声音。刻板语言绝大多数功能为自动强化。反应中断再定向作为一种行为干预,均在个别化的情境下进行,干预时长和频率根据ASD儿童的刻板语言及其他行为障碍的严重程度等进行调整。改变再定向指令内容、数量等的变形反应中断再定向不会对行为改善结果有显著影响,匹配刺激和反应代价等其他干预方法也能够有效地减少刻板语言,但反应中断再定向与这些方法一同使用可能效果更好。反应中断再定向干预不仅可以有效改善ASD儿童语言功能,减少刻板语言,还能增加适当语言、任务参与、指令服从。

基于混合变量目标分解模型的热电联产光储热力电力系统运行优化

光伏、储能电池、燃煤热电联产机组组成的综合能源系统,其电力热力系统间孤立运营,为分析其热力电力系统间的信息交互与经济协调调度的关系,依据J.F.Benders混合变量目标分解法对热电联产光储热力电力系统的物理模型按照热力主系统和电力子系统进行分解,通过目标函数和系统边界条件分析子目标之间的信息交互情况,得出光电消纳储存与热电联产协调调度运行的数学模型,并对保护信息加以隔离重定向,以Gurobi求解器迭代计算混合整数规划多维变量问题。基于综合能源系统案例分析了电力热力不同负荷需求下的3种运行工况,发现热力电力运营系统间经济效益协同互补,且信息交互扩大了光电的消纳空间,系统净负荷平均降低了13.63%,交互功率损失每年减少了948.07万元,能源利用效率提高了4.48百分点,可见本模型可以服务于综合能源系统的经济协调调度优化和提高能效。

A Novel Approach for Redirecting Module in Honeypot Systems

Honeypot is a recent developed computer security concept which uses active offense to against attacks from hackers . It lures hackers to attack a seemly vulnerable fake network where they could be well observed in order to learn about the tactics and tools used by the attackers, so that we may improve the system security accordingly later. In this paper, we propose a novel approach for redirecting technique in honeypot system. First, we introduce briefly concepts of the honeypot system. Then we describe a redirection technique and an implementation algorithm. Finally, using the IDS Snort and the firewall IPTable, we set up a testing environment and give some simulations results. We also discuss some future research topics.

Potent and conditional redirected T cell killing of tumor cells using Half DVD-Ig

Novel biologics that redirect cytotoxic T lymphocytes （CTLs） to kill tumor cells bearing a tumor associated antigen hold great promise in the clinic. However, the ability to safely and potently target CD3 on CTL toward tumor associated antigens （TAA） expressed on tumor cells remains a challenge of both technology and biol- ogy. Herein we describe the use of a Half DVD-Ig format that can redirect CTL to kill tumor cells. Notably, Half DVD-Ig molecules that are monovalent for each speci- ficity demonstrated reduced non-specific CTL activation and conditional CTL activation upon binding to TAA compared to intact tetravalent DVD-Ig molecules that are bivalent for each specificity, while maintaining good drug like properties and appropriate PK properties.

煤矿带式输送机改向滚筒静力学分析

以DLL160/400/4×900煤矿带式输送机为研究对象,对带式输送机改向滚筒静力学分析进行了分析。应用该方法分析时,先要构建出相应的仿真模型,然后分别从静力学、焊缝应力及疲劳寿命等方面着手,全面对带式输送机改向滚筒运行状态进行分析,确定改向滚筒的受力薄弱点,最后通过实例的方式对静力学分析方法应用效果进行评估,以此为煤矿带式输送机改向滚筒的设计提供支持。

Φ830mm煤矿带式输送机改向滚筒的优化设计研究

以DTC80/20/2Χ110S型带式输送机为研究对象,介绍一种基于有限元分析的Φ830煤矿带式输送机改向滚筒优化设计方法。根据改向滚筒结构与材料特性构建出相应的三维模型,并以此为基础分别分析出滚筒的受力情况及模态情况,最后根据分析结果对改向滚筒进行优化。通过该设计优化方法的应用,可保证改向滚筒性能符合要求的同时,降低改向滚筒质量,防止滚筒结构出现共振问题,确认该优化设计方法具有一定应用价值。

煤矿带式输送机改向滚筒疲劳寿命分析及优化

以矿用带式输送机的改向滚筒为研究对象,基于有限元方法开展疲劳寿命分析并进行结构优化改进。在对DTⅡ(A)型带式输送机主要结构及工作原理进行概述的基础上,利用ANSYS软件建立了改向滚筒的有限元模型,通过分析发现疲劳寿命分布存在显著的不均匀性,筒壳中间位置的疲劳寿命最短。以改向滚筒的疲劳寿命为优化目标,确定了三个关键结构的最优参数。将新的结构应用到煤矿工程实践中,结果发现达到了预期效果,其使用寿命预计可延长15%以上,能为企业创造很好的安全效益和经济效益。

矿用架空乘人装置改向滑轮受力分析

以某煤矿架空乘人装置为例,介绍了一种架空乘人装置技术参数优化设计。通过理论分析法获取优化后技术参数后,采用有限元仿真分析法,确认优化后架空乘人装置是否可满足使用需求。另外,研究中采用工业性应用开展优化后架空乘人装置应用价值分析,进而确认优化后架空乘人装置在经济效益和社会效益等方面均表现出较强的优势。

A Comprehensive Review of Redirected Walking Techniques:Taxonomy,Methods,and Future Directions

Virtual reality(VR)allows users to explore and experience a computer-simulated virtual environment so that VR users can be immersed in a totally artificial virtual world and interact with arbitrary virtual objects.However,the limited physical tracking space usually restricts the exploration of large virtual spaces,and VR users have to use special locomotion techniques to move from one location to another.Among these techniques,redirected walking(RDW)is one of the most natural locomotion techniques to solve the problem based on near-natural walking experiences.The core idea of the RDW technique is to imperceptibly guide users on virtual paths,which might vary from the paths they physically walk in the real world.In a similar way,some RDW algorithms imperceptibly change the structure and layout of the virtual environment such that the virtual environment fits into the tracking space.In this survey,we first present a taxonomy of existing RDW work.Based on this taxonomy,we compare and analyze both contributions and shortcomings of the existing methods in detail,and find view manipulation methods offer satisfactory visual effect but the experience can be interrupted when users reach the physical boundaries,while virtual environment manipulation methods can provide users with consistent movement but have limited application scenarios.Finally,we discuss possible future research directions,indicating combining artificial intelligence with this area will be effective and intriguing.

CRISPR-based riboswitches for redirecting the fate of cancer cells

With the support by the National Natural Science Foundation of China,the research team led by Dr.Liu Yuchen(刘宇辰)at the State Engineering Laboratory of Medical Key Technologies Application of Synthetic Biology,Shenzhen Second People’s Hospital,the First Affiliated Hospital of Shenzhen University,developed a type of CRISPR-based riboswitch,which was published in Nature Methods(2016,doi:10.

收获机械发动机冷却变向风扇开发与应用

收获机械作业时发动机转速高,在发动机冷却风扇作用下秸杆及杂草堆积在散热器前阻碍空气流通,导致散热性能差,针对这种问题开发了变向风扇,通过液压系统控制冷却风扇扇叶角度,使风扇在吸风及吹风间转换,从而有效地自动清除散热器吸附的杂物,达到散热系统自清洁的目的。经试验,变向风扇性能满足热平衡要求,可靠性满足1000 h无故障的要求,风扇本体噪声恶化1.78%满足NVH要求。

足球运动员侧切动作中前交叉韧带损伤机制研究

目的:探究足球运动员侧切动作中下肢运动学特点和生物力学特点,确定前交叉韧带的损伤风险因素及损伤过程。研究方法:对长时间进行足球专业训练的运动员进行实验研究,采集生物力学指标、动力学特征指标,采用数据统计、有限元模型进行数据统计分析。结果与结论:足球运动员在侧切动作中受到地面反作用力和膝关节力矩的影响明显;膝关节松弛、胫骨外旋、膝关节外翻、下肢进行低位摇摆动作、髋关节前屈、膝关节过伸、中心方向和双足承重方向不一致、膝关节屈角较小、腘绳肌与股四头肌肌力比值偏低是前交叉韧带损伤的主要风险因素;股四头肌和腘绳肌具有地面反作用力的缓冲作用,进行肌力针对性训练能够降低前交叉韧带损伤的风险。

欺骗诱捕技术在气象网络安全攻防对抗场景下的应用

随着信息技术的快速发展,网络安全形势愈发严峻,气象部门通过组织网络攻防演习,以实战标准检验并提升业务安全防护体系能力。在演习中,攻击队伍对重要业务单位的真实网络及信息系统进行攻击渗透,各业务单位作为防守方开展实时监控与应急处置。由于攻防双方信息不对等,防守方采用传统防御手段经常处于被动挨打的局面。为提升网络防御能力,本文研究伪装欺骗和攻击诱捕技术在气象部门网络安全实战场景下的应用,通过采用基于蜜罐的欺骗诱捕平台,构建主动防御体系,实现对异常网络流量的监测、分析和预警,并对攻击方进行诱捕、溯源。经过实战检验,欺骗诱捕技术的应用切实提高了网络安全防御能力,保障气象业务系统稳定运行。