Video Conference System in Mixed Reality Using a Hololens

The mixed reality conference system proposed in this paper is a robust,real-time video conference application software that makes up for the simple interaction and lack of immersion and realism of traditional video conference,which realizes the entire process of holographic video conference from client to cloud to the client.This paper mainly focuses on designing and implementing a video conference system based on AI segmentation technology and mixed reality.Several mixed reality conference system components are discussed,including data collection,data transmission,processing,and mixed reality presentation.The data layer is mainly used for data collection,integration,and video and audio codecs.The network layer uses Web-RTC to realize peer-to-peer data communication.The data processing layer is the core part of the system,mainly for human video matting and human-computer interaction,which is the key to realizing mixed reality conferences and improving the interactive experience.The presentation layer explicitly includes the login interface of the mixed reality conference system,the presentation of real-time matting of human subjects,and the presentation objects.With the mixed reality conference system,conference participants in different places can see each other in real-time in their mixed reality scene and share presentation content and 3D models based on mixed reality technology to have a more interactive and immersive experience.

Adaptive Consistent Management to Prevent System Collapse on Shared Object Manipulation in Mixed Reality

A concurrency control mechanism for collaborative work is akey element in a mixed reality environment. However, conventional lockingmechanisms restrict potential tasks or the support of non-owners, thusincreasing the working time because of waiting to avoid conflicts. Herein, wepropose an adaptive concurrency control approach that can reduce conflictsand work time. We classify shared object manipulation in mixed reality intodetailed goals and tasks. Then, we model the relationships among goal,task, and ownership. As the collaborative work progresses, the proposedsystem adapts the different concurrency control mechanisms of shared objectmanipulation according to the modeling of goal–task–ownership. With theproposed concurrency control scheme, users can hold shared objects andmove and rotate together in a mixed reality environment similar to realindustrial sites. Additionally, this system provides MS Hololens and Myosensors to recognize inputs from a user and provides results in a mixed realityenvironment. The proposed method is applied to install an air conditioneras a case study. Experimental results and user studies show that, comparedwith the conventional approach, the proposed method reduced the number ofconflicts, waiting time, and total working time.

Training on LSA lifeboat operation using Mixed Reality

Background This work aims to provide an overview of the Mixed Reality(MR)technology’s use in maritime industry for training purposes.Current training procedures cover a broad range of procedural operations for Life-Saving Appliances(LSA)lifeboats;however,several gaps and limitations have been identified related to the practical training that can be addressed through the use of MR.Augmented,Virtual and Mixed Reality applications are already used in various fields in maritime industry,but their full potential have not been yet exploited.SafePASS project aims to exploit MR advantages in the maritime training by introducing a relevant application focusing on use and maintenance of LSA lifeboats.Methods An MR Training application is proposed supporting the training of crew members in equipment usage and operation,as well as in maintenance activities and procedures.The application consists of the training tool that trains crew members on handling lifeboats,the training evaluation tool that allows trainers to assess the performance of trainees,and the maintenance tool that supports crew members to perform maintenance activities and procedures on lifeboats.For each tool,an indicative session and scenario workflow are implemented,along with the main supported interactions of the trainee with the equipment.Results The application has been tested and validated both in lab environment and using a real LSA lifeboat,resulting to improved experience for the users that provided feedback and recommendations for further development.The application has also been demonstrated onboard a cruise ship,showcasing the supported functionalities to relevant stakeholders that recognized the added value of the application and suggested potential future exploitation areas.Conclusions The MR Training application has been evaluated as very promising in providing a user-friendly training environment that can support crew members in LSA lifeboat operation and maintenance,while it is still subject to improvement and further expansion.

Web-based mixed reality video fusion with remote rendering

Background Mixed reality(MR)video fusion systems merge video imagery with 3D scenes to make the scene more realistic and help users understand the video content and temporal–spatial correlation between them,reducing the user′s cognitive load.MR video fusion are used in various applications;however,video fusion systems require powerful client machines because video streaming delivery,stitching,and rendering are computationally intensive.Moreover,huge bandwidth usage is another critical factor that affects the scalability of video-fusion systems.Methods Our framework proposes a fusion method for dynamically projecting video images into 3D models as textures.Results Several experiments on different metrics demonstrate the effectiveness of the proposed framework.Conclusions The framework proposed in this study can overcome client limitations by utilizing remote rendering.Furthermore,the framework we built is based on browsers.Therefore,the user can test the MR video fusion system with a laptop or tablet without installing any additional plug-ins or application programs.

Mixed Reality-based Interactive Technology for Aircraft Cabin Assembly

Due to the narrowness of space and the complexity of structure, the assembly of aircraft cabin has become one of the major bottlenecks in the whole manufacturing process. To solve the problem, at the beginning of aircraft design, the different stages of the lifecycle of aircraft must be thought about, which include the trial manufacture, assembly, maintenance, recycling and destruction of the product. Recently, thanks to the development of the virtual reality and augmented reality, some low-cost and fast solutions are found for the product assembly. This paper presents a mixed reality-based interactive technology for the aircraft cabin assembly, which can enhance the efficiency of the assemblage in a virtual environment in terms of vision, information and operation. In the mixed reality-based assembly environment, the physical scene can be obtained by a camera and then generated by a computer. The virtual parts, the features of visual assembly, the navigation information, the physical parts and the physical assembly environment will be mixed and presented in the same assembly scene. The mixed or the augmented information will provide some assembling information as a detailed assembly instruction in the mixed reality-based assembly environment. Constraint proxy and its match rules help to reconstruct and visualize the restriction relationship among different parts, and to avoid the complex calculation of constraint＇s match. Finally, a desktop prototype system of virtual assembly has been built to assist the assembly verification and training with the virtual hand.

Application value of mixed reality in hepatectomy for hepatocellular carcinoma

BACKGROUND As a new digital holographic imaging technology,mixed reality(MR)technology has unique advantages in determining the liver anatomy and location of tumor lesions.With the popularization of 5 G communication technology,MR shows great potential in preoperative planning and intraoperative navigation,making hepatectomy more accurate and safer.AIM To evaluate the application value of MR technology in hepatectomy for hepatocellular carcinoma(HCC).METHODS The clinical data of 95 patients who underwent open hepatectomy surgery for HCC between June 2018 and October 2020 at our hospital were analyzed retrospectively.We selected 95 patients with HCC according to the inclusion criteria and exclusion criteria.In 38 patients,hepatectomy was assisted by MR(Group A),and an additional 57 patients underwent traditional hepatectomy without MR(Group B).The perioperative outcomes of the two groups were collected and compared to evaluate the application value of MR in hepatectomy for patients with HCC.RESULTS We summarized the technical process of MR-assisted hepatectomy in the treatment of HCC.Compared to traditional hepatectomy in Group B,MR-assisted hepatectomy in Group A yielded a shorter operation time(202.86±46.02 min vs 229.52±57.13 min,P=0.003),less volume of bleeding(329.29±97.31 mL vs 398.23±159.61 mL,P=0.028),and shorter obstructive time of the portal vein(17.71±4.16 min vs 21.58±5.24 min,P=0.019).Group A had lower alanine aminotransferas and higher albumin values on the third day after the operation(119.74±29.08 U/L vs 135.53±36.68 U/L,P=0.029 and 33.60±3.21 g/L vs 31.80±3.51 g/L,P=0.014,respectively).The total postoperative complications and hospitalization days in Group A were significantly less than those in Group B[14(37.84%)vs 35(60.34%),P=0.032 and 12.05±4.04 d vs 13.78±4.13 d,P=0.049,respectively].CONCLUSION MR has some application value in three-dimensional visualization of the liver,surgical planning,and intraoperative navigation during hepatectomy,and it significantly improves the perioperative outcomes of hepatectomy for HCC.

Mixed reality for visualization of orthopedic surgical anatomy

In the modern era,preoperative planning is substantially facilitated by artificial reality technologies,which permit a better understanding of patient anatomy,thus increasing the safety and accuracy of surgical interventions.In the field of orthopedic surgery,the increase in safety and accuracy improves treatment quality and orthopedic patient outcomes.Artificial reality technologies,which include virtual reality(VR),augmented reality(AR),and mixed reality(MR),use digital images obtained from computed tomography or magnetic resonance imaging.VR replaces the user’s physical environment with one that is computer generated.AR and MR have been defined as technologies that permit the fusing of the physical with the virtual environment,enabling the user to interact with both physical and virtual objects.MR has been defined as a technology that,in contrast to AR,enables users to visualize the depth and perspective of the virtual models.We aimed to shed light on the role that MR can play in the visualization of orthopedic surgical anatomy.The literature suggests that MR could be a valuable tool in orthopedic surgeon’s hands for visualization of the anatomy.However,we remark that confusion exists in the literature concerning the characteristics of MR.Thus,a more clear description of MR is needed in orthopedic research,so that the potential of this technology can be more deeply understood.

Uses of a dedicated 3D reconstruction software with augmented and mixed reality in planning and performing advanced liver surgery and living donor liver transplantation(with videos)

The development of digital intelligent diagnostic and treatment technology has opened countless new opportunities for liver surgery from the era of digital anatomy to a new era of digital diagnostics,virtual surgery simulation and using the created scenarios in real-time surgery using mixed reality.In this article,we described our experience on developing a dedicated 3 dimensional visualization and reconstruction software for surgeons to be used in advanced liver surgery and living donor liver transplantation.Furthermore,we shared the recent developments in the field by explaining the outreach of the software from virtual reality to augmented reality and mixed reality.

Electro-oxidation of mixed reactants of ethanol and formate on Pd/C in alkaline fuel cells

Direct ethanol fuel cells have attracted attention as an alternative energy technology due to several advantages such as high theoretical energy density and abundant supply of ethanol.In spite of the advantages,commercialization of direct ethanol fuel cells is hampered by the relatively low performance caused by its slow oxidation kinetics and difficulty of complete oxidation.In this study,formate,which has relatively faster oxidation kinetics,was mixed with ethanol to compensate the latter’s sluggish kinetics.Effects of p H,concentration,scan rate,and temperature on the mixed reactants oxidation on Pd were investigated by electrochemical experiments such as potential sweep and potentiostatic methods.Furthermore,the potential of the mixed reactants as fuel was evaluated by single cell experiments.As a result,we demonstrate that mixing formate with ethanol results in enhanced power performance in a single cell system.

Kinetics modeling for the mixed reforming of methane over Ni-CeO_2/MgAl_2O_4 catalyst

Kinetics model was developed for the mixed （steam and dry） reforming of methane, which is useful for the control of H2/CO ratio. The equilibrium constants of reaction rate were determined using the experimental equilibrium data at different reaction temperatures, while the forward reaction rate constants were estimated using the experimental data under non-equilibrium （high inert fraction and high space velocity） conditions. The comparison between calculated and experimental data clearly showed that the developed model described satisfactorily, and further analysis using the parametric sensitivity determined the wall temperature and CO2 fraction in the feed gas as effective parameters for the manipulation of CH4 conversion and H2/CO ratio of synthesis gas under the equilibrium condition. Meanwhile, the inert fraction, rather than the residence time, was selected as additional parameter under non-equilibrium condition.

Design and analysis of dual mixed refrigerant processes for high-ethane content natural gas liquefaction

Recovery and purification of ethane has a significant impact on economic benefit improvement of the high-ethane content natural gas.However,current LNG-NGL integrated processes mainly focus on conventional natural gas,which are not applicable to natural gas with high ethane content.To fill this gap,three dual mixed refrigerant processes are proposed for simulation study of high-ethane content natural gas liquefaction.The proposed processes are optimized by a combination method of sequence optimization and genetic algorithm.Comparatively analysis is conducted to evaluate the three processes from the energetic and exergetic points of view.The results show that the power consumption of Process 3 which compressing natural gas after distillation is the lowest.For safety or other considerations,some common compositions of the mixed refrigerant may need to be removed under certain circumstances.Considering this,case studies of mixed refrigerant involving six composition combinations are carried out to investigate the effects of refrigerant selection on the process performance.

Design of Learning Media in Mixed Reality for Lao Education

To improve and develop education systems,the communication between instructors and learners in a class during the learning process is of utmost importance.Currently the presentations of 3D models using mixed reality(MR)technology can be used to avoid misinterpretations of oral and 2D model presentations.As an independent concept and MR applications,MR combines the excellent of each virtual reality(VR)and augmented reality(AR).This work aims to present the descriptions of MR systems,which include its devices,applications,and literature reviews and proposes computer vision tracking using the AR Toolkit Tracking Library.The focus of this work will be on creating 3D models and implementing in Unity 3D using the Vuforia SDK platform to develop VR and AR applications for architectural presentations.

Design of Teaching System of Industrial Robots Using Mixed Reality Technology

Traditional teaching and learning about industrial robots uses abstract instructions,which are difficult for students to understand.Meanwhile,there are safety issues associated with the use of practical training equipment.To address these problems,this paper developed an instructional system based on mixed-reality(MR)technology for teaching about industrial robots.The Siasun T6A-series robots were taken as a case study,and the Microsoft MR device HoloLens-2 was used as the instructional platform.First,the parameters of the robots were analyzed based on their structural drawings.Then,the robot modules were decomposed,and 1:1 three-dimensional(3D)digital reproductions were created in Maya.Next,a library of digital models of the robot components was established,and a 3D spatial operation interface for the virtual instructional system was created in Unity.Subsequently,a C#code framework was established to satisfy the requirements of interactive functions and data transmission,and the data were saved in JSON format.In this way,a key technique that facilitates the understanding of spatial structures and a variety of human-machine interactions were realized.Finally,an instructional system based on HoloLens-2 was established for understanding the structures and principles of robots.The results showed that the instructional system developed in this study provides realistic 3D visualizations and a natural,efficient approach for human-machine interactions.This system could effectively improve the efficiency of knowledge transfer and the student’s motivation to learn.

Novel Architecture of OneM2M-Based Convergence Platform for Mixed Reality and IoT

There have been numerous works proposed to merge augmented reality/mixed reality(AR/MR)and Internet of Things(IoT)in various ways.However,they have focused on their specific target applications and have limitations on interoperability or reusability when utilizing them to different domains or adding other devices to the system.This paper proposes a novel architecture of a convergence platform for AR/MR and IoT systems and services.The proposed architecture adopts the oneM2M IoT standard as the basic framework that converges AR/MR and IoT systems and enables the development of application services used in general-purpose environments without being subordinate to specific systems,domains,and device manufacturers.We implement the proposed architecture utilizing the open-source oneM2M-based IoT server and device platforms released by the open alliance for IoT standards(OCEAN)and Microsoft HoloLens as an MR device platform.We also suggest and demonstrate the practical use cases and discuss the advantages of the proposed architecture.

Clinical use of augmented reality,mixed reality,three-dimensionalnavigation and artificial intelligence in liver surgery

A precise knowledge of intra-parenchymal vascular and biliary architecture and the location of lesions in relation to the complex anatomy is indispensable to perform liver surgery.Therefore,virtual three-dimensional(3D)-reconstruction models from computed tomography/magnetic resonance imaging scans of the liver might be helpful for visualization.Augmented reality,mixed reality and 3Dnavigation could transfer such 3D-image data directly into the operation theater to support the surgeon.This review examines the literature about the clinical and intraoperative use of these image guidance techniques in liver surgery and provides the reader with the opportunity to learn about these techniques.Augmented reality and mixed reality have been shown to be feasible for the use in open and minimally invasive liver surgery.3D-navigation facilitated targeting of intraparenchymal lesions.The existing data is limited to small cohorts and description about technical details e.g.,accordance between the virtual 3D-model and the real liver anatomy.Randomized controlled trials regarding clinical data or oncological outcome are not available.Up to now there is no intraoperative application of artificial intelligence in liver surgery.The usability of all these sophisticated image guidance tools has still not reached the grade of immersion which would be necessary for a widespread use in the daily surgical routine.Although there are many challenges,augmented reality,mixed reality,3Dnavigation and artificial intelligence are emerging fields in hepato-biliary surgery.

Application and Prospect of Mixed Reality Technology in Medical Field

Mixed reality(MR)technology is a new digital holographic image technology,which appears in the field of graphics after virtual reality(VR)and augmented reality(AR)technology,a new interdisciplinary frontier.As a new generation of technology,MR has attracted great attention of clinicians in recent years.The emergence of MR will bring about revolutionary changes in medical education training,medical research,medical communication,and clinical treatment.At present,MR technology has become the popular frontline information technology for medical applications.With the popularization of digital technology in the medical field,the development prospects of MR are inestimable.The purpose of this review article is to introduce the application of MR technology in the medical field and prospect its trend in the future.

Mixed reality breathes fresh energy into the development of modern surgery

With the rapid development of holographic imaging technology,virtual reality and augmented reality technology have been used in medicine for decades.However,due to the lack of compatibility between the virtual world and the real world and the lack of human-computer interaction,their widespread use is limited.As a research hotspot in recent years,the mixed reality technology has a huge prospect in the medical field by virtue of its unique advantages combined with the virtual world and the real world,as well as better human-machine realtime interaction and precise matching.This article will focus on the development of this technology in recent years,and introduce the application of mixed reality technology in medical education and clinical application.

Comparing the Functionality between Virtual Reality and Mixed Reality for Architecture and Construction Uses

Virtual Reality (VR) and Mixed Reality (MR) offer unique opportunities for the architecture and construction industry through different approaches with building information modeling (BIM). While VR offers architecture and construction practitioners the ability to personally experience the built environment in an immersive, MR with its unique ability of overlaying digital information in the real world allows practitioners to perform on-site visualization for construction planning and as-built verification. With their similar but distinct characteristics, VR and MR offer a variety of functionality to the architecture and construction industry that often confuses practitioners on what to choose to best fit their needs. To clarify this confusion, this paper investigates the available technologies of VR and MR in terms of both hardware and software and compares the functionality between the two for architecture and construction uses. While VR hardware has been developed into three categories based on their connection types and tracking methods, MR hardware has mainly focused on standalone devices. Eight VR software and nine MR software have been identified, investigated, and compared. This paper provides the latest information for architecture and construction practitioners on how VR and MR hardware and software work similarly and differently.