Artículos de revistas sobre el tema "VR-CAD system"

In this paper, a series of interface tests on interaction approach for the generation of geometric shape designs via multi-sensory user interface of a Virtual Reality (VR) based System is presented. The goal of these interface tests is to identify an effective user interface for VR based Computer-Aided Design (CAD) system. The intuitiveness of the VR based interaction approach arises from the use of natural hand movements/gestures, and voice commands that emulate the way in which human beings discuss geometric shapes in reality. In order to evaluate the proposed interaction approach, a prototypical VR-CAD system is implemented. A series of interface tests were performed on the prototypical systems to determine the relative efficiency of a set of potential interaction approach with respect to specific fundamental design tasks. The interface test and its results are presented in this paper.

In recent years there have been moves in industrial engineering towards greater automation through intelligent systems and this has resulted in replacing human expertise. In many cases the potential of intelligent systems has yet to be realised. This paper presents and discusses an alternative technological approach, which uses immersive virtual reality (VR) to support engineering design tasks. The approach focuses on the human engineer and acknowledges the importance of human input to the design process. The development of a metaphor based VR system is reported along with initial field trials, which compare VR with conventional CAD systems. The results show advantages of using VR over CAD and these are discussed along with strengths, weaknesses and future work.

The adoption of Virtual Reality (RV) technologies in prototype design and process revision has contributed to multiple industry areas. Nonetheless, the development of VR systems for engineering is a complex task, as it involves specialized teams handling low-level code development. Given these problems, the goal of this study is presenting a methodology for designing VR, through an Authoring System based on Computer-Aided Design (CAD). The presented methodology provides an easy integration of electric power substation floor plans and Virtual Reality software (VRS), as well as three-dimensional and symbol modeling conventions. Centralized software architecture was developed, composed of the CAD Editor, input manager and VRS. The methodology was evaluated through a case study applied to the conception (elaboration) of electric power substations (EPS) as part of a Research and Development (R&D) project for training and field assets supervision. The results demonstrated visual precision and high integrity in elaboration of a VR environment from the CAD floor plan. This work also presents a comparative analysis between manual conception and the Authoring System.

In this article we propose an architecture for the inclusion and exploitation of semantic aspects in a CAD environment. Our schema focuses on the enhancement and improvement of a commercial (general purpose) CAD system on its Virtual Reality (VR) capabilities. There is a need in combining CAD and semantics in the new generation of computer assisted engineering systems. Usually semantic aspects in traditional CAD applications relay on the user’s tacit knowledge, a fact that slows the learning curve while the user is getting trained with a new tool, no matter if he is an expert in others. Moreover, current CAD programs offer a myriad of options to the designer, but their limited integration of the non geometric information (e.g. PDM systems), and in general the semantics of the design process, can still be improved for the current needs of the industry. We argue that the use of semantics could improve the workflow and capabilities of the software and would benefit a new user (non experienced one) in order to produce better results in shorter times. In this paper our main focus is the enhancement of the visualization and VR capabilities in generic CAD applications. Our semantic CAD framework uses ontology modeling as well as engineering standards in order to conceptualize and exploit the information contained in a CAD model. To show some benefits of our proposed schema, we present two cases in different engineering domains (plant design and Steel detailing design), where the inclusion of semantics empowers a VR experience.

In this paper is presented an evaluation study regarding the manipulation of 3D CAD models using multimodal Virtual Reality (VR) interface and traditional desktop environment. A multimodal interface based on VR technologies that offers direct access to the space model by using several sensorial channels (visual, tactile, verbal) is described. Users can manipulate 3D objects using 6DOF tracking device, gestures and visualize the design status in an immersive CAVE - like system. The results of the evaluation study illustrate that using VR technologies as an alternative to replace WIMP CAD software interface is viable and brings more advantages.

In view of the high homogeneity of tourism products all over the country, an attempt is made to design virtual visit tourism products with cultural experience background, which can reflect the characteristics of culture + tourism in different scenic spots, so that tourists can deeply experience the local culture. Combined with computer aided design (CAD), the virtual three-dimensional (3D) modeling system of scenic spots is designed, and VR real scene visit interactive tourism products suitable for different scenic spots are designed. 360° VR panoramic display technology is used for 360° VR panoramic video shooting and visiting system display production of Elephant Trunk Hill park scenery. A total of 157 images are collected and 720 cloud panoramic interactive H5 tool is selected to produce a display system suitable for 360° VR panoramic display of scenic spots. Meanwhile, based on single view RGB-D image, the latest convolutional neural network (CNN) algorithm and point cloud processing algorithm are used to design the indoor 3D scene reconstruction algorithm based on semantic understanding. Experiments show that the pixel accuracy and mean intersection over union of the indoor scene layout segmentation network segmentation results are 89.5% and 60.9%, respectively, that is, it has high accuracy. The VR real scene visit interactive tourism product can make tourists have a more immersive sense of interaction and experience before, during and after the tour.

Image-processing technology is widely used in industry for automatic inspection and measurement through the capturing of object images by CCD (Charge-Couple Device) cameras and the built-in algorithms. VR (Virtual Reality) is a high-end user interface that involves real-time simulation and interactions through multiple sensorial channels. Three important characteristics of VR are: immersion, interaction, and imagination which enable the users more direct and useful communications with manufacturing prototyping systems. In this paper, an image processing system was developed for measuring small parts such as 3C rivets automatically. If using optical sensors to measure such small parts, the mechanism is complicate. However, if using image process technology, the mechanism is simple and the measurement is efficient. All we have to do are to develop measuring algorithms as well as computer programs. A VR-based image processing system was also developed by importing 3D CAD objects and applying the relationships between these objects. Therefore, the image processing algorithms as well as the layout of the measurement system can be tested by using the proposed VR system without any real machine such as transfer mechanism, CCD camera, and computer with image processing program.

It’s necessary to apply numerical prototype technology in developing processes of a TBM, and the application of VR system can enormously enhance the simulation effect. In the article, hardware configuration of a VR system for TBM motion simulation was discussed and the module function was analyzed. According to the practical working condition, motion analysis of TBM key components was carried out, and motion model was formulated. A model processing method using Deep Exploration and Creator was introduced, for transforming numerical models from CAD software to VR environment, and for dealing with the accompanying data loss. The article also discussed scene graph constructing method based on OpenGL Performer and developed a TBM motion simulation program.

<p><strong>Abstract.</strong> Virtual reality (VR) technologies are used more and more in product development processes and are upcoming in urban planning systems as well. They help to visualize big amounts of data in self-explanatory way and improve people’s interpretation of results. In this paper we demonstrate the process of visualizing a city model together with wind simulation results in a collaborative VR system. In order to make this kind of visualization possible a considerable amount of preliminary work is necessary: healing and simplification of building models, conversion of these data into an appropriate CAD-format and numerical simulation of wind flow around the buildings. The data obtained from these procedures are visualized in a collaborative VR-System. In our approach CityGML models in the LoD (Level of Detail) 1, 2 and 3 can be used as an input. They are converted into the STEP format, commonly used in CAD for simulation and representation. For this publication we use an exemplary LoD1 model from the district Stöckach-Stuttgart. After preprocessing the model, the results are combined with those of an air flow simulation and afterwards depicted in a VR system with a HTC Vive as well as in a CAVE and a Powerwall. This provides researchers, city planners and technicians with the means to flexibly and interactively exchange simulation results in a virtual environment.</p>

The development and maintenance of a virtual reality (VR) system requires indepth knowledge and understanding in many different disciplines. Three major features that distinguish VR systems are real-time performance while maintaining acceptable realism and presence, objects with two clearly distinct yet inter-related aspects like geometry/structure and function/behavior, and the still experimental nature of multi-modal interaction design. Until now, little attention has been paid to methods and tools for the structured development of VR software that addresses these features. Many VR application development projects proceed by modeling needed objects on conventional CAD systems, then programming the system using simulation packages. Usually, these activities are carried out without much planning, which may be acceptable for only small-scale or noncritical demonstration systems. However, for VR to be taken seriously as a media technology, a structural approach to developing VR applications is required for the construction of large-scale VR worlds, and this will undoubtedly involve and require complex resource management, abstractions for basic system/object functionalities and interaction tasks, and integration and easy plug-ins of different input and output methods. In this paper, we assembled a comprehensive structured methodology for building VR systems, called CLEVR (Concurrent and LEvel by Level Development of VR System), which combines several conventional and new concepts. For instance, we employ concepts such as the simultaneous consideration of form, function, and behavior, hierarchical modeling and top-down creation of LODs (levels of detail), incremental execution and performance tuning, user task and interaction modeling, and compositional reuse of VR objects. The basic underlying modeling approach is to design VR objects (and the scenes they compose) hierarchically and incrementally, considering their realism, presence, behavioral correctness, performance, and even usability in a spiral manner. To support this modeling strategy, we developed a collection of computeraided tools called P-VoT (POSTECH-Virtual reality system development Tool). We demonstrate our approach by illustrating a step-by-step design of a virtual ship simulator using the CLEVR/P-VoT, and demonstrate the effectiveness of our method in terms of the quality (performance and correctness) of the resulting software and reduced effort in its development and maintenance.

An intelligent E-Manufacturing system was developed in this paper. The high speed machining center was rebuilt using 3D CAD system. The moving table (X axis), span column (Y axis), spindle (Z axis) and the tool changing system were modeled precisely. The high speed cutting (HSC) experiments of AL 6061 were carried to obtain the cutting forces and surface roughness for different cutting conditions. The backward propagation supervised artificial neural network (ANN) system was developed to predict the results of the high speed cutting. The intelligent virtual reality (VR) system of high speed cutting was developed integration the ANN and the VR environment. The users were able to learn the manual and the CNC operations of the HSC machine. The actions of users were recorded and evaluated to judge the learning results. The cutting results of forces and surface roughness of user’s NC program was predicted by the ANN system to assist the NC programmer to adopt the suitable cutting parameters. The developed VR system was deployed to the internet webpage to supply a good E-Learning and E-Manufacturing environment.

For the purpose of improving the efficiency of garment design, the computer-aided garment design virtual reality (VR) model for surplus fabric removal and reuse without segmentation of cutting pieces is analyzed in this paper to provide the architecture of the computer-aided garment design CAD system. The form of dividing the garment into multiple types of nonsegmented pieces is adopted so that each nonsegmented piece stands for a complete design element unit. Based on this structure, the computer analysis of garment design based on CAD can be connected at a deeper level, which will not only improve the design efficiency of new garments but also reduce the design time at the client terminal and enhance the quality of the design. Through the experimental operation of prototypes, it is verified that the intelligent system proposed in this paper can implement the design of prototypes quickly and effectively.

Due to complex process and high difficult operation for large-scale products assembly, the application of virtual assembly (VA) has an important significance and also an actual value. In this paper the key techniques of VA for large-scale complex products are proposed, and their assembly characteristics (such as their organization form, human participation, process planning and optimization and so on) are analyzed. First, a new virtual environment (VE) system considering human activities is set up. Second, an integration approach is realized to transform data from CAD to VA system, and a hybrid method on the basis of virtual reality (VR) and intelligent algorithm is applied to optimize and evaluate assembly process planning. Moreover, assembly documents generation and Web training for assembly workers are implemented. Finally, an application case of the VA system for a complex product is given, and further work is pointed out.

The paper presents the conception of integration of a robot virtual model with its virtual control system. The system of connections between the virtual world and the control system of a virtual model, proposed in the work, should let for developing the technical approach allowing teaching the manual programming of robots. In the paper attempted to define particular subsystems included in the proposed system for teaching programming of robots. In the work it have been distinguished problems that should be solved in order to properly create the proposed virtual system, and namely problems related to the: creation of a robotic system model in CAD systems, including modelling of a robot and its technological equipment; modelling of functioning of a real system in the applications of the VR (Virtual Reality) class; creation of a robot control system basing on a high level programming language (control application); elaboration of a virtual robot control panel (hardware interface); determination of the appropriate stereoscopic projection system and creation of the interfaces between the particular subsystems.

This article provides a concrete example for using and creating a virtual environment for computer-aided design of complex systems. The subject area is design, and the object of research is an aircraft. CAD creates a parameterized 3D model, which is demonstrated and processed on a virtual stage using special equipment. Special equipment such as the HTC Vive Pro virtual reality helmet and the included controllers. The virtual assistant of the designer allows you to create detailed parameterized models of an aircraft, in particular, a transport aircraft based on the An-124 Ruslan, and virtual reality helps the user to learn more about the created project and make the necessary optimization edits directly in VR space. By changing the model in VR space, it will change in the main project. The work is a continuation of the development of a decision-making system, a virtual assistant to the designer: "Robot designer", whose application interface has been defined. The main control menu for the user in virtual space is shown, and the aircraft with the fuselage skin and cockpit removed is also shown. Plans for further use of virtual reality technology in the design of complex systems and training of specialists with the profile of aircraft engineers are presented.

Virtual Reality (VR) has made considerable gains in the consumer and professional markets. As VR has progressed as a technology, its overall usefulness for educational purposes has grown. On the other hand, the educational field struggles to keep up with the latest innovations, changing affordances, and pedagogical applications due to the rapid evolution of technology. Therefore, many have elaborated on the potential of virtual reality (VR) in learning. This research proposes a novel techniques customized curriculum for medical students and recommendations for their learning process based on deep learning techniques. Here the data has been collected based on the pre-historic performance of the student and their current requirement and these data have been created as a dataset. Then this has been processed for analysis based on CAD system integrated with deep learning techniques for creating a customized curriculum. Initially this data has been processed and analysed to remove missing and invalid data. Then these data were classified for creation of the curriculum using a gradient decision tree integrated&nbsp;with na&iuml;ve Bayes. From this, the customized curriculum has been generated. Based on this customized curriculum, the learning approach recommendation has been carried out using the fuzzy rules integrated knowledge-based recommendation system. The experimental results of the proposed technique have been carried out with an accuracy of 98%, specificity of 82%, F-1 score of 79%, information overload of 75%, and precision of 81%.

The future development of the manufacturing is using VR technology to make the machining simulation before the actual machining process made. The machining simulation of Ultra High-speed Grinding Machine Tool is researched in this paper. Firstly, using UG/NX software and VRML, the geometric modeling of machine tool is modeled. Secondly, through using Java and Javascript language, the operation and display of machining process of ultra high-speed grinding are realized. The main technologies include NC codes compiling, collision detection and material removal. Thirdly, the example of machining simulation using virtual ultra high-speed grinding machine tool can be obtained in the paper. Compared to other CNC machining simulation methods, the method in the paper has reality display, rich features, a good man-machine interaction, etc., and it does not rely on expensive CAD/CAM software. The system files generated by the machining simulation have the small size and can be transferred on the network easily.

In this paper is presented a Virtual Reality application that can be used for automatic generation of robot trajectories for spray painting operations conducted on products with complex surfaces. The trajectory generation for robots that perform painting operations of complex curved surfaces was achieved by implementing a generic algorithm capable of maintaining an optimal distance for painting. The distance between the effecter of the robot and the surface of the CAD model, used to compensate and maintain an optimal painting distance, is determined by a "rayhit" collision detection algorithm that allows the detection of the contact between a linear segment and the mesh of the virtual object. To visualize in the virtual environment the deposition of paint layers, an algorithm was implemented that is based on mapping techniques for dynamically generated textures on the surface that is being painted. A VR software application was developed for generating and visualizing the trajectories of a KUKA robotic system that performs the activity of painting a complex curved product.

Architecture students use both analog and digital tools throughout their design process. Ideally, the affordances of each tool complement each other. Our goal with Kitoparts is to move beyond two-dimensional screen based computer modeling environments to create a system that feels analog but harnesses all the affordances of digital modeling environments. With the usage of VR and haptic controllers, we hope to provide a rich and flexible methodology for investigating forms and space. In educational settings, Kitoparts aims to solve three major problems with traditional beginning design exercises. First, it solves the scaling problem, allowing design students to see their designs visualized at full scale and in real-time. Second, it overcomes the combinatorial nature of physical building blocks by allowing 3D shapes to overlap and embed into each other in ways they could not within the physical world. Finally, we include the designer’s “hands” in the creative process. Virtual hands prove to be much more intuitive to use than the traditional mouse and keyboards commonly utilized in most CAD and modeling software. With Kitoparts, the computer model is no longer just a tool for representation; it becomes the user interface for design. Kitoparts allows both seasoned designers and novices to simply play, build, and explore.

Construction technology is a collective term for types of technology that have a specific use within the construction industry. Adoption of recent digital transformation technology is the need of today to speed up the business and is also the basis of construction improvement. Incorporating and practicing the technologies such as cloud-based communication and collaboration solution, Mobile Apps and 5G,3D printing, Building Information Modelling (BIM) and Digital Twins, CAD / CAM, Augmented Reality(AR)/ Virtual Reality(VR), Big Data, Internet of Things(IoT), Wearables, Blockchain(BC), Modular Construction(MC), Offsite Manifesting, Prefabrication(PF), Robotic, Drones and Global Positioning System (GPS) controlled equipment expedite the progress in the Construction industry (CI). Resources used are journaled research articles, web/net surfing, books, thesis, reports/surveys, magazines, etc. The outline of the research organization for this study is framed at four distinct levels in context to conceptualization, resources, innovative and emerging trends in CI, and better methods for completion of the construction projects. The present study conducted during 2020-2022 reveals that implementing these technologies improves the level of standards, planning, security, well-being, sustainability, and economics too. Application uses, benefits, impact, advantages/disadvantages, limitations and challenges, and policies are dealt with to provide information to architects and builders for smooth completion of the project. Results explain that construction technology trends vary from 4 to 15 for CI, and eventually, it reaches 27 for Civil Engineering (CE). The perspective of the most recent innovations, trends, tools, challenges, and solutions is highly embraced in the field of construction. The incorporation of the above said technologies in the pandemic Covid -19and post-pandemic might lead to a focus on finding out effective ways to adopt new-age technologies for CI.

Abstract The coordination process plays a vital role in construction projects during the design phase when interferences and clashes between design systems are identified to reduce the risk of costly reworks. Despite the fact that coordination has been studied commonly in BIM research, limited research has explored the impact of virtual reality (VR) to understand how it can enhance the process. This research study examined the effectiveness of coordination processes in a building renovation project following an innovative approach based on virtual environments (3D-BIM VR) compared to the conventional approach (2D CAD). This research uses the Cyclotron Charette Test method to analyse both approaches in terms of accuracy, speed, and usability. Fifteen participants from engineering backgrounds participated in the prototype testing divided into two experiments. The first experiment involved visually identifying clashes from multiple 2D CAD drawings, while the second involved visually identifying clashes from 3D-BIM-based VR models. The results showed that the virtual reality environment not only helped uncover clashes quickly but also made it more accurate and helpful. A further finding from this research indicates that motion sickness hinders users’’ participation in VR environments. Finally, future research pathways are discussed to improve the coordination process using VR technology

In this paper, we propose a VR design tool framework called DREAMSCAPE, which adopts a direct manipulation approach focusing on embody, experience, and manipulation activities in design. The framework defines a VR design process using intuitive controls without being limited by the preconceptions of conventional CAD systems. To establish and demonstrate the framework, we designed and developed a VR design tool called Dreamscape Bricks VR in Unreal Engine 4, using LEGO bricks as base components in a high-fidelity interactive design environment. We conducted user tests and administered questionnaires assessing usability, performance, and comfort. Results showed that the user experience of the tool is positive. The developed tool is expected to establish the abstract framework and provide insights into the future of VR design tools with implications on design education

Canine atopic dermatitis (AD) is a common skin disease with a 10–15 per cent prevalence. Current treatments vary in their efficacy and safety. The immunomodulatory properties of mesenchymal stem cells (MSCs) make them a promising alternative treatment. The aim of this study was to evaluate the therapeutic efficacy and safety of allogeneic canine adipose MSCs (cAd-MSCs) in dogs with refractory AD. Twenty-six dogs, suffering from AD for at least 12 months, not responding to conventional therapy, received an intravenous dose of 1.5×106 cAd-MSCs/kg bodyweight. Clinical signs, haematological and biochemistry profiles, and AD severity were assessed in a six-month follow-up using a validated scoring system (Canine Atopic Dermatitis Extent and Severity Index, version 4 (CADESI-04)). The degree of pruritus was quantified using a validated visual analogue scale, and also owner’s global assessment of treatment efficacy. Twenty-two animals completed the study. Pruritus and CADESI-04 scores decreased significantly after one week or month of treatment, respectively, and remained stable for six months. Owner’s global assessment score was 2.15±1.15 for all the animals in the study. In conclusion, systemic administration of allogeneic cAd-MSCs appeared to be a simple therapy with positive outcome in the remission of clinical signs for AD refractory to conventional medications, for at least six months and with no adverse events.

This article reviews the experience of application of VR-AR technologies (virtual and augmented reality technologies) for visual demonstration of production facilities in the process of engineering and operation. The three-dimensional modeling in CAD systems is commonly used as a means for development of construction documentation, visualization of work at different stages of engineering, and preparation of objects for engineering analysis. The authors believe that the use of AR-solutions not in parallel, but along with modern CAD systems for solution of engineering and design problems would allow avoiding design flaws and simplify the process of demonstration of projects. Based on the blueprints and three-dimensional models of the parts and assembly of two-stage reduction gear used &nbsp;for lifting a thermal furnace in metallurgical production, within the framework of development of the Unity multimedia application is developed the AR application for visual demonstration of the device. As the guide mark for visualization is selected the assembly drawing of the reduction gear in digital graphical format edited in the Vuforia portal. The guide mark database is imported into the Unity environment, the logic of implementation of the technique for demonstrating the assembly of the device and separate parts is written in script program. The application is installed on a smartphone and tested; pointing the camera at the printed assembly drawing allows seeing the 3D model of the reduction gear from different angles, hide any details and scrutinize the device. The AR-applications developed according to the proposed method can be used in the process of training operational personnel, which would improve the performance and quality of work during installation and maintenance of industrial facilities, as well as for displaying the projects during exhibitions and presentations of new products.

Due to changes in the global industrial structure, the number of employees in the manufacturing industry has decreased in developed countries. One of solutions to this situation offered in Industry 4.0 is “the utilization of robots and AI as alternatives to skilled workers.” This solution has been applied to various operations conventionally performed by skilled workers and has yielded consistent results. A skilled worker has two skills, namely, “physical operation skill” and “decision making skill,” which correspond to the utilization of robots and AI, respectively. Conventionally, robots have simply played back programs they were taught. However, owing to feedback technologies using force, position, or various other sensors, robots have come to be able to perform smart operations. In some of these, the capabilities of robots exceed those of human workers. For example, while humans are highly adaptive to various operations, it is difficult for them to maintain a constant force or position for long periods of time. Generally, humans make decisions about operations according to their experience, and this experience is gained from many instances of trial and error. Now, the trial-and-error learning of AI has become significantly superior to that of humans in terms of both number and speed. As a result, many systems can find operational strategies or answers much faster than humans can. This special issue features papers on robot hands, path planning, kinematics, and AI. Papers related to robot hands present an actuator using new principles, new movements, and the realization of the precise sense of the human hand. Papers related to path planning present path generation on the basis of CAD data, path generation using image processing, automatic path generation on the basis of environmental information, and the prediction of error and correction. Path generation using VR technology and error compensation using an AI technique are also presented. A paper related to kinematics presents the analysis and evaluation of a new mechanism with the aim of new applications in the field of machining. In closing, I would like to thank the authors, reviewers, and editors, without whose hard work and earnest cooperation this issue could not have been completed and presented.

Abstract The goal of the PITSTOP (Immersive platform for structured operator training) project is to overcome the limits of traditional workplace training on dangerous systems and reduce the related risks, using an innovative integration of engineering simulation models and virtual reality (VR) tools. This article specifically presents the first VR platform for training on small-scale industrial steam generators, representative of a vast class of hazardous industrial equipment. The dynamic model of the steam generator was developed in Matlab-Simulink using a mixed physics-based and data-driven approach. The generator model includes the main engineering components, actuators and measuring equipment, as well as control logic and emergency procedures. It can simulate normal operation and emergency situations. The model was calibrated using experimental data collected from the real system at various operating conditions to align simulated performance with the real behavior. The VR environment was developed in Unity, a graphics engine widely adopted by the videogame industry, using 3D CAD models of the steam generator and its surroundings. The user can access this immersive system wearing an HTC VIVE headset. Unlike most existing training systems, learners can interact with the actuators using bare hands gestures, without controllers, making the experience intuitive and easily accessible. By connecting the dynamic model with the VR environment, the user's interactions are directly provided to the steam generator model, which in turn directly outputs the steam generator response to the VR environment, providing audio and visual feedback the user, as if they were actually acting on the real generator. The results from this study could boost the further development of training platforms to safely train operators and certify their competence.

AIM: Virtual reality (VR) based technologies have been used in dentistry for almost two decades. Dental simulators, treatment planning software, and CAD/CAM systems have evolved significantly over the years, changing both dental education and clinical practice. The purpose of this survey study is to learn the knowledge, opinions, and thoughts of dental students in our country on the use of VR-based dental simulators in education, and to raise awareness on this issue. METHODS: Questions testing participants’ knowledge were based on the data from peer-reviewed dental journals. The survey questions consisting of a total of 25 questions were delivered online via Google Forms (Google Inc., USA) to students who had preclinical training in the dental faculty before the Covid-19 pandemic. The data obtained were evaluated using the descriptive statistics and Pearson chi-square test. RESULTS: 422 of the 662 students in the study were female and 240 were male students. 82.3% of the study participants were studying at a state university. 74.6% of the participants in the study stated that they needed more preclinical education. While 89.9% of the students participating in the survey stated that they do not have information about preclinical education with virtual reality, 97.4% stated that they have not used a VR-based dental simulator before. 85.5% of them stated that they feel positive about training in virtual environment with VR-based dental simulator and 86% of them prefer using both VR-based training and phantom models in preclinical training. CONCLUSION: Dental students had overall positive attitudes towards VR-based dental simulator but very few used VR-based dental simulators in education and practice. While using VR-based dental simulators as part of undergraduate and continuing education programs is rapidly advancing in the world, in our country having knowledge about VR-based dental simulators will increase awareness for the development of such technologies and their inclusion in dentistry education.

Abstract Logistic processes of construction sites are transferred into virtual and full 3D environments to increase the interoperability for all project partners. These digital twins are emerging for the construction process of modern building processes and are already designed to be used for the operation of the building afterwards. In structural health monitoring (SHM) the sensor installations are also designed to monitor the structure over its whole lifespan. Therefore, the embedding process and the operation of the sensor systems and the Building Information Modelling (BIM) have overlapping long-term goals. Beside these 3D software advances in civil engineering, the working environments in the field of geodesy still follow more established approaches. In many cases using only 2D CAD plans and on-site visits at the existing structure are best practice for the design of geodetic monitoring installations. This paper describes the improvement of the concept creation of permanent monitoring systems with geodetic total stations in an interactive virtual 3D environment. The simulated instruments are behaving according to their specification data and are linked with a physics engine to automatically detect common problems in a network design like obstructed line of sights, disadvantageous incidence angles at the targets or automatic aiming issues due to multiple targets in the field of view. Furthermore, the Virtual Reality (VR) technology is introduced as a user interface for a virtual 3D planning environment. The functionality of the developed VR application is tested in a real-life use case for the feasibility study of the automatic monitoring of a railway tunnel.

Introdução: O maior foco das pesquisas odontológicas nos últimos 60 anos tem sido a adesão e suas técnicas. Mais de 7000 artigos já foram publicados a este respeito. O desenvolvimento dos materiais odontológicos adesivos e as técnicas a eles relacionadas possuem uma história interessante, onde descobertas do passado ainda são usadas de alguma forma no presente. Objetivo: expor, através de uma revisão de literatura, um breve histórico sobre materiais e técnicas restauradoras, bem como o estágio atual da odontologia adesiva, com ênfase na tradução de evidências baseadas em pesquisas laboratoriais para a prática clínica. Materiais e Métodos: Foram selecionados livros de preferência do autor para a introdução de conceitos clássicos e artigos de revisão publicados nos últimos 10 anos, utilizando as cinco palavras-chave: “Dental Bonding” AND “Dental Cements” AND “Resin Cements” AND “Adhesives” AND “Ceramics”, sorteados pela melhor combinação na plataforma Pub/Med/MEDLINE. Resultados: Duzentos e um artigos, foram encontrados, sendo utilizados para análise qualitativa e quantitativa aqueles pertinentes ao direcionamento do autor, de acordo com o tema. Conclusão: Considerando as limitações do estudo, concluiu-se que a odontologia adesiva é uma área que segue em constante desenvolvimento, fundamental para a realização de restaurações minimamente invasivas e estéticas. Onde para que seja possível consequentemente longevidade clínica, os materiais utilizados e substrato dentário requerem conhecimento do profissional e fidelidade na execução de um correto pré-tratamento das superfícies, respeitando suas naturezas e composições.Descritores: Colagem Dentária; Cimentos Dentários; Cimentos de Resina; Adesivos; Cerâmica.ReferênciasVan Meerbeek B, De Munck J, Yoshida Y, Inoue S, Vargas M, Vijay P, et al. Buonocore memorial lecture. Adhesion to enamel and dentin: current status and future challenges. Oper Dent. 2003;28:215-35.Miyashita E, Fonseca AS. 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