Web-based Three-dimensional Virtual Body Structures: W3D-VBS

PubMed Central

Temkin, Bharti; Acosta, Eric; Hatfield, Paul; Onal, Erhan; Tong, Alex

2002-01-01

Major efforts are being made to improve the teaching of human anatomy to foster cognition of visuospatial relationships. The Visible Human Project of the National Library of Medicine makes it possible to create virtual reality-based applications for teaching anatomy. Integration of traditional cadaver and illustration-based methods with Internet-based simulations brings us closer to this goal. Web-based three-dimensional Virtual Body Structures (W3D-VBS) is a next-generation immersive anatomical training system for teaching human anatomy over the Internet. It uses Visible Human data to dynamically explore, select, extract, visualize, manipulate, and stereoscopically palpate realistic virtual body structures with a haptic device. Tracking user’s progress through evaluation tools helps customize lesson plans. A self-guided “virtual tour” of the whole body allows investigation of labeled virtual dissections repetitively, at any time and place a user requires it. PMID:12223495

Web-based three-dimensional Virtual Body Structures: W3D-VBS.

PubMed

Temkin, Bharti; Acosta, Eric; Hatfield, Paul; Onal, Erhan; Tong, Alex

2002-01-01

Major efforts are being made to improve the teaching of human anatomy to foster cognition of visuospatial relationships. The Visible Human Project of the National Library of Medicine makes it possible to create virtual reality-based applications for teaching anatomy. Integration of traditional cadaver and illustration-based methods with Internet-based simulations brings us closer to this goal. Web-based three-dimensional Virtual Body Structures (W3D-VBS) is a next-generation immersive anatomical training system for teaching human anatomy over the Internet. It uses Visible Human data to dynamically explore, select, extract, visualize, manipulate, and stereoscopically palpate realistic virtual body structures with a haptic device. Tracking user's progress through evaluation tools helps customize lesson plans. A self-guided "virtual tour" of the whole body allows investigation of labeled virtual dissections repetitively, at any time and place a user requires it.

3D geospatial visualizations: Animation and motion effects on spatial objects

NASA Astrophysics Data System (ADS)

Evangelidis, Konstantinos; Papadopoulos, Theofilos; Papatheodorou, Konstantinos; Mastorokostas, Paris; Hilas, Constantinos

2018-02-01

Digital Elevation Models (DEMs), in combination with high quality raster graphics provide realistic three-dimensional (3D) representations of the globe (virtual globe) and amazing navigation experience over the terrain through earth browsers. In addition, the adoption of interoperable geospatial mark-up languages (e.g. KML) and open programming libraries (Javascript) makes it also possible to create 3D spatial objects and convey on them the sensation of any type of texture by utilizing open 3D representation models (e.g. Collada). One step beyond, by employing WebGL frameworks (e.g. Cesium.js, three.js) animation and motion effects are attributed on 3D models. However, major GIS-based functionalities in combination with all the above mentioned visualization capabilities such as for example animation effects on selected areas of the terrain texture (e.g. sea waves) as well as motion effects on 3D objects moving in dynamically defined georeferenced terrain paths (e.g. the motion of an animal over a hill, or of a big fish in an ocean etc.) are not widely supported at least by open geospatial applications or development frameworks. Towards this we developed and made available to the research community, an open geospatial software application prototype that provides high level capabilities for dynamically creating user defined virtual geospatial worlds populated by selected animated and moving 3D models on user specified locations, paths and areas. At the same time, the generated code may enhance existing open visualization frameworks and programming libraries dealing with 3D simulations, with the geospatial aspect of a virtual world.

Research on 3D virtual campus scene modeling based on 3ds Max and VRML

NASA Astrophysics Data System (ADS)

Kang, Chuanli; Zhou, Yanliu; Liang, Xianyue

2015-12-01

With the rapid development of modem technology, the digital information management and the virtual reality simulation technology has become a research hotspot. Virtual campus 3D model can not only express the real world objects of natural, real and vivid, and can expand the campus of the reality of time and space dimension, the combination of school environment and information. This paper mainly uses 3ds Max technology to create three-dimensional model of building and on campus buildings, special land etc. And then, the dynamic interactive function is realized by programming the object model in 3ds Max by VRML .This research focus on virtual campus scene modeling technology and VRML Scene Design, and the scene design process in a variety of real-time processing technology optimization strategy. This paper guarantees texture map image quality and improve the running speed of image texture mapping. According to the features and architecture of Guilin University of Technology, 3ds Max, AutoCAD and VRML were used to model the different objects of the virtual campus. Finally, the result of virtual campus scene is summarized.

3D workflow for HDR image capture of projection systems and objects for CAVE virtual environments authoring with wireless touch-sensitive devices

NASA Astrophysics Data System (ADS)

Prusten, Mark J.; McIntyre, Michelle; Landis, Marvin

2006-02-01

A 3D workflow pipeline is presented for High Dynamic Range (HDR) image capture of projected scenes or objects for presentation in CAVE virtual environments. The methods of HDR digital photography of environments vs. objects are reviewed. Samples of both types of virtual authoring being the actual CAVE environment and a sculpture are shown. A series of software tools are incorporated into a pipeline called CAVEPIPE, allowing for high-resolution objects and scenes to be composited together in natural illumination environments [1] and presented in our CAVE virtual reality environment. We also present a way to enhance the user interface for CAVE environments. The traditional methods of controlling the navigation through virtual environments include: glove, HUD's and 3D mouse devices. By integrating a wireless network that includes both WiFi (IEEE 802.11b/g) and Bluetooth (IEEE 802.15.1) protocols the non-graphical input control device can be eliminated. Therefore wireless devices can be added that would include: PDA's, Smart Phones, TabletPC's, Portable Gaming consoles, and PocketPC's.

Real-time fusion of endoscopic views with dynamic 3-D cardiac images: a phantom study.

PubMed

Szpala, Stanislaw; Wierzbicki, Marcin; Guiraudon, Gerard; Peters, Terry M

2005-09-01

Minimally invasive robotically assisted cardiac surgical systems currently do not routinely employ 3-D image guidance. However, preoperative magnetic resonance and computed tomography (CT) images have the potential to be used in this role, if appropriately registered with the patient anatomy and animated synchronously with the motion of the actual heart. This paper discusses the fusion of optical images of a beating heart phantom obtained from an optically tracked endoscope, with volumetric images of the phantom created from a dynamic CT dataset. High quality preoperative dynamic CT images are created by first extracting the motion parameters of the heart from the series of temporal frames, and then applying this information to animate a high-quality heart image acquired at end systole. Temporal synchronization of the endoscopic and CT model is achieved by selecting the appropriate CT image from the dynamic set, based on an electrocardiographic trigger signal. The spatial error between the optical and virtual images is 1.4 +/- 1.1 mm, while the time discrepancy is typically 50-100 ms. Index Terms-Image guidance, image warping, minimally invasive cardiac surgery, virtual endoscopy, virtual reality.

Camera pose estimation for augmented reality in a small indoor dynamic scene

NASA Astrophysics Data System (ADS)

Frikha, Rawia; Ejbali, Ridha; Zaied, Mourad

2017-09-01

Camera pose estimation remains a challenging task for augmented reality (AR) applications. Simultaneous localization and mapping (SLAM)-based methods are able to estimate the six degrees of freedom camera motion while constructing a map of an unknown environment. However, these methods do not provide any reference for where to insert virtual objects since they do not have any information about scene structure and may fail in cases of occlusion of three-dimensional (3-D) map points or dynamic objects. This paper presents a real-time monocular piece wise planar SLAM method using the planar scene assumption. Using planar structures in the mapping process allows rendering virtual objects in a meaningful way on the one hand and improving the precision of the camera pose and the quality of 3-D reconstruction of the environment by adding constraints on 3-D points and poses in the optimization process on the other hand. We proposed to benefit from the 3-D planes rigidity motion in the tracking process to enhance the system robustness in the case of dynamic scenes. Experimental results show that using a constrained planar scene improves our system accuracy and robustness compared with the classical SLAM systems.

Versatile, Immersive, Creative and Dynamic Virtual 3-D Healthcare Learning Environments: A Review of the Literature

PubMed Central

2008-01-01

The author provides a critical overview of three-dimensional (3-D) virtual worlds and “serious gaming” that are currently being developed and used in healthcare professional education and medicine. The relevance of this e-learning innovation for teaching students and professionals is debatable and variables influencing adoption, such as increased knowledge, self-directed learning, and peer collaboration, by academics, healthcare professionals, and business executives are examined while looking at various Web 2.0/3.0 applications. There is a need for more empirical research in order to unearth the pedagogical outcomes and advantages associated with this e-learning technology. A brief description of Roger’s Diffusion of Innovations Theory and Siemens’ Connectivism Theory for today’s learners is presented as potential underlying pedagogical tenets to support the use of virtual 3-D learning environments in higher education and healthcare. PMID:18762473

Versatile, immersive, creative and dynamic virtual 3-D healthcare learning environments: a review of the literature.

PubMed

Hansen, Margaret M

2008-09-01

The author provides a critical overview of three-dimensional (3-D) virtual worlds and "serious gaming" that are currently being developed and used in healthcare professional education and medicine. The relevance of this e-learning innovation for teaching students and professionals is debatable and variables influencing adoption, such as increased knowledge, self-directed learning, and peer collaboration, by academics, healthcare professionals, and business executives are examined while looking at various Web 2.0/3.0 applications. There is a need for more empirical research in order to unearth the pedagogical outcomes and advantages associated with this e-learning technology. A brief description of Roger's Diffusion of Innovations Theory and Siemens' Connectivism Theory for today's learners is presented as potential underlying pedagogical tenets to support the use of virtual 3-D learning environments in higher education and healthcare.

CliniSpace: a multiperson 3D online immersive training environment accessible through a browser.

PubMed

Dev, Parvati; Heinrichs, W LeRoy; Youngblood, Patricia

2011-01-01

Immersive online medical environments, with dynamic virtual patients, have been shown to be effective for scenario-based learning (1). However, ease of use and ease of access have been barriers to their use. We used feedback from prior evaluation of these projects to design and develop CliniSpace. To improve usability, we retained the richness of prior virtual environments but modified the user interface. To improve access, we used a Software-as-a-Service (SaaS) approach to present a richly immersive 3D environment within a web browser.

Dense and dynamic 3D selection for game-based virtual environments.

PubMed

Cashion, Jeffrey; Wingrave, Chadwick; LaViola, Joseph J

2012-04-01

3D object selection is more demanding when, 1) objects densly surround the target object, 2) the target object is significantly occluded, and 3) when the target object is dynamically changing location. Most 3D selection techniques and guidelines were developed and tested on static or mostly sparse environments. In contrast, games tend to incorporate densly packed and dynamic objects as part of their typical interaction. With the increasing popularity of 3D selection in games using hand gestures or motion controllers, our current understanding of 3D selection needs revision. We present a study that compared four different selection techniques under five different scenarios based on varying object density and motion dynamics. We utilized two existing techniques, Raycasting and SQUAD, and developed two variations of them, Zoom and Expand, using iterative design. Our results indicate that while Raycasting and SQUAD both have weaknesses in terms of speed and accuracy in dense and dynamic environments, by making small modifications to them (i.e., flavoring), we can achieve significant performance increases.

Infusion of a Gaming Paradigm into Computer-Aided Engineering Design Tools

DTIC Science & Technology

2012-05-03

Virtual Test Bed (VTB), and the gaming tool, Unity3D . This hybrid gaming environment coupled a three-dimensional (3D) multibody vehicle system model...from Google Earth to the 3D visual front-end fabricated around Unity3D . The hybrid environment was sufficiently developed to support analyses of the...ndFr Cti3r4 G’OjrdFr ctior-2 The VTB simulation of the vehicle dynamics ran concurrently with and interacted with the gaming engine, Unity3D which

Hierarchical Task Network Prototyping In Unity3d

DTIC Science & Technology

2016-06-01

visually debug. Here we present a solution for prototyping HTNs by extending an existing commercial implementation of Behavior Trees within the Unity3D game ...HTN, dynamic behaviors, behavior prototyping, agent-based simulation, entity-level combat model, game engine, discrete event simulation, virtual...commercial implementation of Behavior Trees within the Unity3D game engine prior to building the HTN in COMBATXXI. Existing HTNs were emulated within

Generating Contextual Descriptions of Virtual Reality (VR) Spaces

NASA Astrophysics Data System (ADS)

Olson, D. M.; Zaman, C. H.; Sutherland, A.

2017-12-01

Virtual reality holds great potential for science communication, education, and research. However, interfaces for manipulating data and environments in virtual worlds are limited and idiosyncratic. Furthermore, speech and vision are the primary modalities by which humans collect information about the world, but the linking of visual and natural language domains is a relatively new pursuit in computer vision. Machine learning techniques have been shown to be effective at image and speech classification, as well as at describing images with language (Karpathy 2016), but have not yet been used to describe potential actions. We propose a technique for creating a library of possible context-specific actions associated with 3D objects in immersive virtual worlds based on a novel dataset generated natively in virtual reality containing speech, image, gaze, and acceleration data. We will discuss the design and execution of a user study in virtual reality that enabled the collection and the development of this dataset. We will also discuss the development of a hybrid machine learning algorithm linking vision data with environmental affordances in natural language. Our findings demonstrate that it is possible to develop a model which can generate interpretable verbal descriptions of possible actions associated with recognized 3D objects within immersive VR environments. This suggests promising applications for more intuitive user interfaces through voice interaction within 3D environments. It also demonstrates the potential to apply vast bodies of embodied and semantic knowledge to enrich user interaction within VR environments. This technology would allow for applications such as expert knowledge annotation of 3D environments, complex verbal data querying and object manipulation in virtual spaces, and computer-generated, dynamic 3D object affordances and functionality during simulations.

Virtual Environment for Surgical Room of the Future.

DTIC Science & Technology

1995-10-01

Design; 1. wire frame Dynamic Interaction 2. surface B. Acoustic Three-Dimensional Modeling; 3. solid based on radiosity modeling B. Dynamic...infection control of people and E. Rendering and Shadowing equipment 1. ray tracing D. Fluid Flow 2. radiosity F. Animation OBJECT RECOGNITION COMMUNICATION

Systematic literature review of digital three-dimensional superimposition techniques to create virtual dental patients.

PubMed

Joda, Tim; Brägger, Urs; Gallucci, German

2015-01-01

Digital developments have led to the opportunity to compose simulated patient models based on three-dimensional (3D) skeletal, facial, and dental imaging. The aim of this systematic review is to provide an update on the current knowledge, to report on the technical progress in the field of 3D virtual patient science, and to identify further research needs to accomplish clinical translation. Searches were performed electronically (MEDLINE and OVID) and manually up to March 2014 for studies of 3D fusion imaging to create a virtual dental patient. Inclusion criteria were limited to human studies reporting on the technical protocol for superimposition of at least two different 3D data sets and medical field of interest. Of the 403 titles originally retrieved, 51 abstracts and, subsequently, 21 full texts were selected for review. Of the 21 full texts, 18 studies were included in the systematic review. Most of the investigations were designed as feasibility studies. Three different types of 3D data were identified for simulation: facial skeleton, extraoral soft tissue, and dentition. A total of 112 patients were investigated in the development of 3D virtual models. Superimposition of data on the facial skeleton, soft tissue, and/or dentition is a feasible technique to create a virtual patient under static conditions. Three-dimensional image fusion is of interest and importance in all fields of dental medicine. Future research should focus on the real-time replication of a human head, including dynamic movements, capturing data in a single step.

Research on multi - channel interactive virtual assembly system for power equipment under the “VR+” era

NASA Astrophysics Data System (ADS)

Ren, Yilong; Duan, Xitong; Wu, Lei; He, Jin; Xu, Wu

2017-06-01

With the development of the “VR+” era, the traditional virtual assembly system of power equipment has been unable to satisfy our growing needs. In this paper, based on the analysis of the traditional virtual assembly system of electric power equipment and the application of VR technology in the virtual assembly system of electric power equipment in our country, this paper puts forward the scheme of establishing the virtual assembly system of power equipment: At first, we should obtain the information of power equipment, then we should using OpenGL and multi texture technology to build 3D solid graphics library. After the completion of three-dimensional modeling, we can use the dynamic link library DLL package three-dimensional solid graphics generation program to realize the modularization of power equipment model library and power equipment model library generated hidden algorithm. After the establishment of 3D power equipment model database, we set up the virtual assembly system of 3D power equipment to separate the assembly operation of the power equipment from the space. At the same time, aiming at the deficiency of the traditional gesture recognition algorithm, we propose a gesture recognition algorithm based on improved PSO algorithm for BP neural network data glove. Finally, the virtual assembly system of power equipment can really achieve multi-channel interaction function.

Explore the virtual side of earth science

USGS Publications Warehouse

,

1998-01-01

Scientists have always struggled to find an appropriate technology that could represent three-dimensional (3-D) data, facilitate dynamic analysis, and encourage on-the-fly interactivity. In the recent past, scientific visualization has increased the scientist's ability to visualize information, but it has not provided the interactive environment necessary for rapidly changing the model or for viewing the model in ways not predetermined by the visualization specialist. Virtual Reality Modeling Language (VRML 2.0) is a new environment for visualizing 3-D information spaces and is accessible through the Internet with current browser technologies. Researchers from the U.S. Geological Survey (USGS) are using VRML as a scientific visualization tool to help convey complex scientific concepts to various audiences. Kevin W. Laurent, computer scientist, and Maura J. Hogan, technical information specialist, have created a collection of VRML models available through the Internet at Virtual Earth Science (virtual.er.usgs.gov).

A virtual simulator designed for collision prevention in proton therapy.

PubMed

Jung, Hyunuk; Kum, Oyeon; Han, Youngyih; Park, Hee Chul; Kim, Jin Sung; Choi, Doo Ho

2015-10-01

In proton therapy, collisions between the patient and nozzle potentially occur because of the large nozzle structure and efforts to minimize the air gap. Thus, software was developed to predict such collisions between the nozzle and patient using treatment virtual simulation. Three-dimensional (3D) modeling of a gantry inner-floor, nozzle, and robotic-couch was performed using SolidWorks based on the manufacturer's machine data. To obtain patient body information, a 3D-scanner was utilized right before CT scanning. Using the acquired images, a 3D-image of the patient's body contour was reconstructed. The accuracy of the image was confirmed against the CT image of a humanoid phantom. The machine components and the virtual patient were combined on the treatment-room coordinate system, resulting in a virtual simulator. The simulator simulated the motion of its components such as rotation and translation of the gantry, nozzle, and couch in real scale. A collision, if any, was examined both in static and dynamic modes. The static mode assessed collisions only at fixed positions of the machine's components, while the dynamic mode operated any time a component was in motion. A collision was identified if any voxels of two components, e.g., the nozzle and the patient or couch, overlapped when calculating volume locations. The event and collision point were visualized, and collision volumes were reported. All components were successfully assembled, and the motions were accurately controlled. The 3D-shape of the phantom agreed with CT images within a deviation of 2 mm. Collision situations were simulated within minutes, and the results were displayed and reported. The developed software will be useful in improving patient safety and clinical efficiency of proton therapy.

A Standard-Compliant Virtual Meeting System with Active Video Object Tracking

NASA Astrophysics Data System (ADS)

Lin, Chia-Wen; Chang, Yao-Jen; Wang, Chih-Ming; Chen, Yung-Chang; Sun, Ming-Ting

2002-12-01

This paper presents an H.323 standard compliant virtual video conferencing system. The proposed system not only serves as a multipoint control unit (MCU) for multipoint connection but also provides a gateway function between the H.323 LAN (local-area network) and the H.324 WAN (wide-area network) users. The proposed virtual video conferencing system provides user-friendly object compositing and manipulation features including 2D video object scaling, repositioning, rotation, and dynamic bit-allocation in a 3D virtual environment. A reliable, and accurate scheme based on background image mosaics is proposed for real-time extracting and tracking foreground video objects from the video captured with an active camera. Chroma-key insertion is used to facilitate video objects extraction and manipulation. We have implemented a prototype of the virtual conference system with an integrated graphical user interface to demonstrate the feasibility of the proposed methods.

The dynamics of student learning within a high school virtual reality design class

NASA Astrophysics Data System (ADS)

Morales, Teresa M.

This mixed method study investigated knowledge and skill development of high school students in a project-based VR design class, in which 3-D projects were developed within a student-centered, student-directed environment. This investigation focused on student content learning, and problem solving. Additionally the social dynamics of the class and the role of peer mentoring were examined to determine how these factors influenced student behavior and learning. Finally, parent and teachers perceptions of the influence of the class were examined. The participants included freshmen through senior students, parents, teachers and the high school principal. Student interviews and classroom observations were used to collect data from students, while teachers and parents completed surveys. The results of this study suggested that this application of virtual reality (VR) learning environment promoted the development of; meaningful cognitive experiences, creativity, leadership, global socialization, problem solving and a deeper understanding of academic content. Further theoretical implications for 3-D virtual reality technology are exceedingly promising, and warrant additional research and development as an instructional tool for practical use.

Virtual reality 3D echocardiography in the assessment of tricuspid valve function after surgical closure of ventricular septal defect.

PubMed

Bol Raap, Goris; Koning, Anton H J; Scohy, Thierry V; ten Harkel, A Derk-Jan; Meijboom, Folkert J; Kappetein, A Pieter; van der Spek, Peter J; Bogers, Ad J J C

2007-02-16

This study was done to investigate the potential additional role of virtual reality, using three-dimensional (3D) echocardiographic holograms, in the postoperative assessment of tricuspid valve function after surgical closure of ventricular septal defect (VSD). 12 data sets from intraoperative epicardial echocardiographic studies in 5 operations (patient age at operation 3 weeks to 4 years and bodyweight at operation 3.8 to 17.2 kg) after surgical closure of VSD were included in the study. The data sets were analysed as two-dimensional (2D) images on the screen of the ultrasound system as well as holograms in an I-space virtual reality (VR) system. The 2D images were assessed for tricuspid valve function. In the I-Space, a 6 degrees-of-freedom controller was used to create the necessary projectory positions and cutting planes in the hologram. The holograms were used for additional assessment of tricuspid valve leaflet mobility. All data sets could be used for 2D as well as holographic analysis. In all data sets the area of interest could be identified. The 2D analysis showed no tricuspid valve stenosis or regurgitation. Leaflet mobility was considered normal. In the virtual reality of the I-Space, all data sets allowed to assess the tricuspid leaflet level in a single holographic representation. In 3 holograms the septal leaflet showed restricted mobility that was not appreciated in the 2D echocardiogram. In 4 data sets the posterior leaflet and the tricuspid papillary apparatus were not completely included. This report shows that dynamic holographic imaging of intraoperative postoperative echocardiographic data regarding tricuspid valve function after VSD closure is feasible. Holographic analysis allows for additional tricuspid valve leaflet mobility analysis. The large size of the probe, in relation to small size of the patient, may preclude a complete data set. At the moment the requirement of an I-Space VR system limits the applicability in virtual reality 3D echocardiography in clinical practice.

VEDA: a web-based virtual environment for dynamic atomic force microscopy.

PubMed

Melcher, John; Hu, Shuiqing; Raman, Arvind

2008-06-01

We describe here the theory and applications of virtual environment dynamic atomic force microscopy (VEDA), a suite of state-of-the-art simulation tools deployed on nanoHUB (www.nanohub.org) for the accurate simulation of tip motion in dynamic atomic force microscopy (dAFM) over organic and inorganic samples. VEDA takes advantage of nanoHUB's cyberinfrastructure to run high-fidelity dAFM tip dynamics computations on local clusters and the teragrid. Consequently, these tools are freely accessible and the dAFM simulations are run using standard web-based browsers without requiring additional software. A wide range of issues in dAFM ranging from optimal probe choice, probe stability, and tip-sample interaction forces, power dissipation, to material property extraction and scanning dynamics over hetereogeneous samples can be addressed.

Invited Article: VEDA: A web-based virtual environment for dynamic atomic force microscopy

NASA Astrophysics Data System (ADS)

Melcher, John; Hu, Shuiqing; Raman, Arvind

2008-06-01

We describe here the theory and applications of virtual environment dynamic atomic force microscopy (VEDA), a suite of state-of-the-art simulation tools deployed on nanoHUB (www.nanohub.org) for the accurate simulation of tip motion in dynamic atomic force microscopy (dAFM) over organic and inorganic samples. VEDA takes advantage of nanoHUB's cyberinfrastructure to run high-fidelity dAFM tip dynamics computations on local clusters and the teragrid. Consequently, these tools are freely accessible and the dAFM simulations are run using standard web-based browsers without requiring additional software. A wide range of issues in dAFM ranging from optimal probe choice, probe stability, and tip-sample interaction forces, power dissipation, to material property extraction and scanning dynamics over hetereogeneous samples can be addressed.

Vision-based navigation in a dynamic environment for virtual human

NASA Astrophysics Data System (ADS)

Liu, Yan; Sun, Ji-Zhou; Zhang, Jia-Wan; Li, Ming-Chu

2004-06-01

Intelligent virtual human is widely required in computer games, ergonomics software, virtual environment and so on. We present a vision-based behavior modeling method to realize smart navigation in a dynamic environment. This behavior model can be divided into three modules: vision, global planning and local planning. Vision is the only channel for smart virtual actor to get information from the outside world. Then, the global and local planning module use A* and D* algorithm to find a way for virtual human in a dynamic environment. Finally, the experiments on our test platform (Smart Human System) verify the feasibility of this behavior model.

Evaluation of two 3D virtual computer reconstructions for comparison of cleft lip and palate to normal fetal microanatomy.

PubMed

Landes, Constantin A; Weichert, Frank; Geis, Philipp; Helga, Fritsch; Wagner, Mathias

2006-03-01

Cleft lip and palate reconstructive surgery requires thorough knowledge of normal and pathological labial, palatal, and velopharyngeal anatomy. This study compared two software algorithms and their 3D virtual anatomical reconstruction because exact 3D micromorphological reconstruction may improve learning, reveal spatial relationships, and provide data for mathematical modeling. Transverse and frontal serial sections of the midface of 18 fetal specimens (11th to 32nd gestational week) were used for two manual segmentation approaches. The first manual segmentation approach used bitmap images and either Windows-based or Mac-based SURFdriver commercial software that allowed manual contour matching, surface generation with average slice thickness, 3D triangulation, and real-time interactive virtual 3D reconstruction viewing. The second manual segmentation approach used tagged image format and platform-independent prototypical SeViSe software developed by one of the authors (F.W.). Distended or compressed structures were dynamically transformed. Registration was automatic but allowed manual correction, such as individual section thickness, surface generation, and interactive virtual 3D real-time viewing. SURFdriver permitted intuitive segmentation, easy manual offset correction, and the reconstruction showed complex spatial relationships in real time. However, frequent software crashes and erroneous landmarks appearing "out of the blue," requiring manual correction, were tedious. Individual section thickness, defined smoothing, and unlimited structure number could not be integrated. The reconstruction remained underdimensioned and not sufficiently accurate for this study's reconstruction problem. SeViSe permitted unlimited structure number, late addition of extra sections, and quantified smoothing and individual slice thickness; however, SeViSe required more elaborate work-up compared to SURFdriver, yet detailed and exact 3D reconstructions were created.

Getting the point across: exploring the effects of dynamic virtual humans in an interactive museum exhibit on user perceptions.

PubMed

Rivera-Gutierrez, Diego; Ferdig, Rick; Li, Jian; Lok, Benjamin

2014-04-01

We have created “You, M.D.”, an interactive museum exhibit in which users learn about topics in public health literacy while interacting with virtual humans. You, M.D. is equipped with a weight sensor, a height sensor and a Microsoft Kinect that gather basic user information. Conceptually, You, M.D. could use this user information to dynamically select the appearance of the virtual humans in the interaction attempting to improve learning outcomes and user perception for each particular user. For this concept to be possible, a better understanding of how different elements of the visual appearance of a virtual human affects user perceptions is required. In this paper, we present the results of an initial user study with a large sample size (n =333) ran using You, M.D. The study measured users’ reactions based on the user’s gender and body-mass index (BMI) when facing virtual humans with BMI either concordant or discordant from the user’s BMI. The results of the study indicate that concordance between the users’ BMI and the virtual human’s BMI affects male and female users differently. The results also show that female users rate virtual humans as more knowledgeable than male users rate the same virtual humans.

WWW creates new interactive 3D graphics and collaborative environments for medical research and education.

PubMed

Samothrakis, S; Arvanitis, T N; Plataniotis, A; McNeill, M D; Lister, P F

1997-11-01

Virtual Reality Modelling Language (VRML) is the start of a new era for medicine and the World Wide Web (WWW). Scientists can use VRML across the Internet to explore new three-dimensional (3D) worlds, share concepts and collaborate together in a virtual environment. VRML enables the generation of virtual environments through the use of geometric, spatial and colour data structures to represent 3D objects and scenes. In medicine, researchers often want to interact with scientific data, which in several instances may also be dynamic (e.g. MRI data). This data is often very large and is difficult to visualise. A 3D graphical representation can make the information contained in such large data sets more understandable and easier to interpret. Fast networks and satellites can reliably transfer large data sets from computer to computer. This has led to the adoption of remote tale-working in many applications including medical applications. Radiology experts, for example, can view and inspect in near real-time a 3D data set acquired from a patient who is in another part of the world. Such technology is destined to improve the quality of life for many people. This paper introduces VRML (including some technical details) and discusses the advantages of VRML in application developing.

NEDE: an open-source scripting suite for developing experiments in 3D virtual environments.

PubMed

Jangraw, David C; Johri, Ansh; Gribetz, Meron; Sajda, Paul

2014-09-30

As neuroscientists endeavor to understand the brain's response to ecologically valid scenarios, many are leaving behind hyper-controlled paradigms in favor of more realistic ones. This movement has made the use of 3D rendering software an increasingly compelling option. However, mastering such software and scripting rigorous experiments requires a daunting amount of time and effort. To reduce these startup costs and make virtual environment studies more accessible to researchers, we demonstrate a naturalistic experimental design environment (NEDE) that allows experimenters to present realistic virtual stimuli while still providing tight control over the subject's experience. NEDE is a suite of open-source scripts built on the widely used Unity3D game development software, giving experimenters access to powerful rendering tools while interfacing with eye tracking and EEG, randomizing stimuli, and providing custom task prompts. Researchers using NEDE can present a dynamic 3D virtual environment in which randomized stimulus objects can be placed, allowing subjects to explore in search of these objects. NEDE interfaces with a research-grade eye tracker in real-time to maintain precise timing records and sync with EEG or other recording modalities. Python offers an alternative for experienced programmers who feel comfortable mastering and integrating the various toolboxes available. NEDE combines many of these capabilities with an easy-to-use interface and, through Unity's extensive user base, a much more substantial body of assets and tutorials. Our flexible, open-source experimental design system lowers the barrier to entry for neuroscientists interested in developing experiments in realistic virtual environments. Copyright © 2014 Elsevier B.V. All rights reserved.

Proof of concept : examining characteristics of roadway infrastructure in various 3D visualization modes.

DOT National Transportation Integrated Search

2015-02-01

Utilizing enhanced visualization in transportation planning and design gained popularity in the last decade. This work aimed at : demonstrating the concept of utilizing a highly immersive, virtual reality simulation engine for creating dynamic, inter...

Large depth of focus dynamic micro integral imaging for optical see-through augmented reality display using a focus-tunable lens.

PubMed

Shen, Xin; Javidi, Bahram

2018-03-01

We have developed a three-dimensional (3D) dynamic integral-imaging (InIm)-system-based optical see-through augmented reality display with enhanced depth range of a 3D augmented image. A focus-tunable lens is adopted in the 3D display unit to relay the elemental images with various positions to the micro lens array. Based on resolution priority integral imaging, multiple lenslet image planes are generated to enhance the depth range of the 3D image. The depth range is further increased by utilizing both the real and virtual 3D imaging fields. The 3D reconstructed image and the real-world scene are overlaid using an optical see-through display for augmented reality. The proposed system can significantly enhance the depth range of a 3D reconstructed image with high image quality in the micro InIm unit. This approach provides enhanced functionality for augmented information and adjusts the vergence-accommodation conflict of a traditional augmented reality display.

Comparative analysis of video processing and 3D rendering for cloud video games using different virtualization technologies

NASA Astrophysics Data System (ADS)

Bada, Adedayo; Alcaraz-Calero, Jose M.; Wang, Qi; Grecos, Christos

2014-05-01

This paper describes a comprehensive empirical performance evaluation of 3D video processing employing the physical/virtual architecture implemented in a cloud environment. Different virtualization technologies, virtual video cards and various 3D benchmarks tools have been utilized in order to analyse the optimal performance in the context of 3D online gaming applications. This study highlights 3D video rendering performance under each type of hypervisors, and other factors including network I/O, disk I/O and memory usage. Comparisons of these factors under well-known virtual display technologies such as VNC, Spice and Virtual 3D adaptors reveal the strengths and weaknesses of the various hypervisors with respect to 3D video rendering and streaming.

Mesoscopic Rigid Body Modelling of the Extracellular Matrix Self-Assembly.

PubMed

Wong, Hua; Prévoteau-Jonquet, Jessica; Baud, Stéphanie; Dauchez, Manuel; Belloy, Nicolas

2018-06-11

The extracellular matrix (ECM) plays an important role in supporting tissues and organs. It even has a functional role in morphogenesis and differentiation by acting as a source of active molecules (matrikines). Many diseases are linked to dysfunction of ECM components and fragments or changes in their structures. As such it is a prime target for drugs. Because of technological limitations for observations at mesoscopic scales, the precise structural organisation of the ECM is not well-known, with sparse or fuzzy experimental observables. Based on the Unity3D game and physics engines, along with rigid body dynamics, we propose a virtual sandbox to model large biological molecules as dynamic chains of rigid bodies interacting together to gain insight into ECM components behaviour in the mesoscopic range. We have preliminary results showing how parameters such as fibre flexibility or the nature and number of interactions between molecules can induce different structures in the basement membrane. Using the Unity3D game engine and virtual reality headset coupled with haptic controllers, we immerse the user inside the corresponding simulation. Untrained users are able to navigate a complex virtual sandbox crowded with large biomolecules models in a matter of seconds.

V-Man Generation for 3-D Real Time Animation. Chapter 5

NASA Technical Reports Server (NTRS)

Nebel, Jean-Christophe; Sibiryakov, Alexander; Ju, Xiangyang

2007-01-01

The V-Man project has developed an intuitive authoring and intelligent system to create, animate, control and interact in real-time with a new generation of 3D virtual characters: The V-Men. It combines several innovative algorithms coming from Virtual Reality, Physical Simulation, Computer Vision, Robotics and Artificial Intelligence. Given a high-level task like "walk to that spot" or "get that object", a V-Man generates the complete animation required to accomplish the task. V-Men synthesise motion at runtime according to their environment, their task and their physical parameters, drawing upon its unique set of skills manufactured during the character creation. The key to the system is the automated creation of realistic V-Men, not requiring the expertise of an animator. It is based on real human data captured by 3D static and dynamic body scanners, which is then processed to generate firstly animatable body meshes, secondly 3D garments and finally skinned body meshes.

Modeling mechanical cardiopulmonary interactions for virtual environments.

PubMed

Kaye, J M

1997-01-01

We have developed a computer system for modeling mechanical cardiopulmonary behavior in an interactive, 3D virtual environment. The system consists of a compact, scalar description of cardiopulmonary mechanics, with an emphasis on respiratory mechanics, that drives deformable 3D anatomy to simulate mechanical behaviors of and interactions between physiological systems. Such an environment can be used to facilitate exploration of cardiopulmonary physiology, particularly in situations that are difficult to reproduce clinically. We integrate 3D deformable body dynamics with new, formal models of (scalar) cardiorespiratory physiology, associating the scalar physiological variables and parameters with corresponding 3D anatomy. Our approach is amenable to modeling patient-specific circumstances in two ways. First, using CT scan data, we apply semi-automatic methods for extracting and reconstructing the anatomy to use in our simulations. Second, our scalar models are defined in terms of clinically-measurable, patient-specific parameters. This paper describes our approach and presents a sample of results showing normal breathing and acute effects of pneumothoraces.

Wireless physiological monitoring and ocular tracking: 3D calibration in a fully-immersive virtual health care environment.

PubMed

Zhang, Lelin; Chi, Yu Mike; Edelstein, Eve; Schulze, Jurgen; Gramann, Klaus; Velasquez, Alvaro; Cauwenberghs, Gert; Macagno, Eduardo

2010-01-01

Wireless physiological/neurological monitoring in virtual reality (VR) offers a unique opportunity for unobtrusively quantifying human responses to precisely controlled and readily modulated VR representations of health care environments. Here we present such a wireless, light-weight head-mounted system for measuring electrooculogram (EOG) and electroencephalogram (EEG) activity in human subjects interacting with and navigating in the Calit2 StarCAVE, a five-sided immersive 3-D visualization VR environment. The system can be easily expanded to include other measurements, such as cardiac activity and galvanic skin responses. We demonstrate the capacity of the system to track focus of gaze in 3-D and report a novel calibration procedure for estimating eye movements from responses to the presentation of a set of dynamic visual cues in the StarCAVE. We discuss cyber and clinical applications that include a 3-D cursor for visual navigation in VR interactive environments, and the monitoring of neurological and ocular dysfunction in vision/attention disorders.

Molecular Dynamics Visualization (MDV): Stereoscopic 3D Display of Biomolecular Structure and Interactions Using the Unity Game Engine.

PubMed

Wiebrands, Michael; Malajczuk, Chris J; Woods, Andrew J; Rohl, Andrew L; Mancera, Ricardo L

2018-06-21

Molecular graphics systems are visualization tools which, upon integration into a 3D immersive environment, provide a unique virtual reality experience for research and teaching of biomolecular structure, function and interactions. We have developed a molecular structure and dynamics application, the Molecular Dynamics Visualization tool, that uses the Unity game engine combined with large scale, multi-user, stereoscopic visualization systems to deliver an immersive display experience, particularly with a large cylindrical projection display. The application is structured to separate the biomolecular modeling and visualization systems. The biomolecular model loading and analysis system was developed as a stand-alone C# library and provides the foundation for the custom visualization system built in Unity. All visual models displayed within the tool are generated using Unity-based procedural mesh building routines. A 3D user interface was built to allow seamless dynamic interaction with the model while being viewed in 3D space. Biomolecular structure analysis and display capabilities are exemplified with a range of complex systems involving cell membranes, protein folding and lipid droplets.

Sensor Spatial Distortion, Visual Latency, and Update Rate Effects on 3D Tracking in Virtual Environments

NASA Technical Reports Server (NTRS)

Ellis, S. R.; Adelstein, B. D.; Baumeler, S.; Jense, G. J.; Jacoby, R. H.; Trejo, Leonard (Technical Monitor)

1998-01-01

Several common defects that we have sought to minimize in immersing virtual environments are: static sensor spatial distortion, visual latency, and low update rates. Human performance within our environments during large amplitude 3D tracking was assessed by objective and subjective methods in the presence and absence of these defects. Results show that 1) removal of our relatively small spatial sensor distortion had minor effects on the tracking activity, 2) an Adapted Cooper-Harper controllability scale proved the most sensitive subjective indicator of the degradation of dynamic fidelity caused by increasing latency and decreasing frame rates, and 3) performance, as measured by normalized RMS tracking error or subjective impressions, was more markedly influenced by changing visual latency than by update rate.

DHM and serious games: a case-study oil and gas laboratories.

PubMed

Santos, V; Zamberlan, M; Streit, P; Oliveira, J; Guimarães, C; Pastura, F; Cid, G

2012-01-01

The aim in this paper is to present a research on the application of serious games for the design of laboratories in the oil and gas industries. The focus is in human virtual representation acquired from 3D scanning, human interaction, workspace layout and equipment designed considering ergonomics standards. The laboratory studies were simulated in Unity3D platform, which allows the users to control the DHM1 on the dynamic virtual scenario, in order to simulate work activities. This methodology can change the design process by improving the level of interaction between final users, managers and human factor teams. That helps to better visualize future work settings and improve the level of participation between all stakeholders.

Integration of the virtual 3D model of a control system with the virtual controller

NASA Astrophysics Data System (ADS)

Herbuś, K.; Ociepka, P.

2015-11-01

Nowadays the design process includes simulation analysis of different components of a constructed object. It involves the need for integration of different virtual object to simulate the whole investigated technical system. The paper presents the issues related to the integration of a virtual 3D model of a chosen control system of with a virtual controller. The goal of integration is to verify the operation of an adopted object of in accordance with the established control program. The object of the simulation work is the drive system of a tunneling machine for trenchless work. In the first stage of work was created an interactive visualization of functioning of the 3D virtual model of a tunneling machine. For this purpose, the software of the VR (Virtual Reality) class was applied. In the elaborated interactive application were created adequate procedures allowing controlling the drive system of a translatory motion, a rotary motion and the drive system of a manipulator. Additionally was created the procedure of turning on and off the output crushing head, mounted on the last element of the manipulator. In the elaborated interactive application have been established procedures for receiving input data from external software, on the basis of the dynamic data exchange (DDE), which allow controlling actuators of particular control systems of the considered machine. In the next stage of work, the program on a virtual driver, in the ladder diagram (LD) language, was created. The control program was developed on the basis of the adopted work cycle of the tunneling machine. The element integrating the virtual model of the tunneling machine for trenchless work with the virtual controller is the application written in a high level language (Visual Basic). In the developed application was created procedures responsible for collecting data from the running, in a simulation mode, virtual controller and transferring them to the interactive application, in which is verified the operation of the adopted research object. The carried out work allowed foot the integration of the virtual model of the control system of the tunneling machine with the virtual controller, enabling the verification of its operation.

Fast virtual functional assessment of intermediate coronary lesions using routine angiographic data and blood flow simulation in humans: comparison with pressure wire - fractional flow reserve.

PubMed

Papafaklis, Michail I; Muramatsu, Takashi; Ishibashi, Yuki; Lakkas, Lampros S; Nakatani, Shimpei; Bourantas, Christos V; Ligthart, Jurgen; Onuma, Yoshinobu; Echavarria-Pinto, Mauro; Tsirka, Georgia; Kotsia, Anna; Nikas, Dimitrios N; Mogabgab, Owen; van Geuns, Robert-Jan; Naka, Katerina K; Fotiadis, Dimitrios I; Brilakis, Emmanouil S; Garcia-Garcia, Héctor M; Escaned, Javier; Zijlstra, Felix; Michalis, Lampros K; Serruys, Patrick W

2014-09-01

To develop a simplified approach of virtual functional assessment of coronary stenosis from routine angiographic data and test it against fractional flow reserve using a pressure wire (wire-FFR). Three-dimensional quantitative coronary angiography (3D-QCA) was performed in 139 vessels (120 patients) with intermediate lesions assessed by wire-FFR (reference standard: ≤0.80). The 3D-QCA models were processed with computational fluid dynamics (CFD) to calculate the lesion-specific pressure gradient (ΔP) and construct the ΔP-flow curve, from which the virtual functional assessment index (vFAI) was derived. The discriminatory power of vFAI for ischaemia- producing lesions was high (area under the receiver operator characteristic curve [AUC]: 92% [95% CI: 86-96%]). Diagnostic accuracy, sensitivity and specificity for the optimal vFAI cut-point (≤0.82) were 88%, 90% and 86%, respectively. Virtual-FAI demonstrated superior discrimination against 3D-QCA-derived % area stenosis (AUC: 78% [95% CI: 70- 84%]; p<0.0001 compared to vFAI). There was a close correlation (r=0.78, p<0.0001) and agreement of vFAI compared to wire-FFR (mean difference: -0.0039±0.085, p=0.59). We developed a fast and simple CFD-powered virtual haemodynamic assessment model using only routine angiography and without requiring any invasive physiology measurements/hyperaemia induction. Virtual-FAI showed a high diagnostic performance and incremental value to QCA for predicting wire-FFR; this "less invasive" approach could have important implications for patient management and cost.

Aurally aided visual search performance in a dynamic environment

NASA Astrophysics Data System (ADS)

McIntire, John P.; Havig, Paul R.; Watamaniuk, Scott N. J.; Gilkey, Robert H.

2008-04-01

Previous research has repeatedly shown that people can find a visual target significantly faster if spatial (3D) auditory displays direct attention to the corresponding spatial location. However, previous research has only examined searches for static (non-moving) targets in static visual environments. Since motion has been shown to affect visual acuity, auditory acuity, and visual search performance, it is important to characterize aurally-aided search performance in environments that contain dynamic (moving) stimuli. In the present study, visual search performance in both static and dynamic environments is investigated with and without 3D auditory cues. Eight participants searched for a single visual target hidden among 15 distracting stimuli. In the baseline audio condition, no auditory cues were provided. In the 3D audio condition, a virtual 3D sound cue originated from the same spatial location as the target. In the static search condition, the target and distractors did not move. In the dynamic search condition, all stimuli moved on various trajectories at 10 deg/s. The results showed a clear benefit of 3D audio that was present in both static and dynamic environments, suggesting that spatial auditory displays continue to be an attractive option for a variety of aircraft, motor vehicle, and command & control applications.

Shock-driven fluid-structure interaction for civil design

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wood, Stephen L; Deiterding, Ralf

The multiphysics fluid-structure interaction simulation of shock-loaded structures requires the dynamic coupling of a shock-capturing flow solver to a solid mechanics solver for large deformations. The Virtual Test Facility combines a Cartesian embedded boundary approach with dynamic mesh adaptation in a generic software framework of flow solvers using hydrodynamic finite volume upwind schemes that are coupled to various explicit finite element solid dynamics solvers (Deiterding et al., 2006). This paper gives a brief overview of the computational approach and presents first simulations that utilize the general purpose solid dynamics code DYNA3D for complex 3D structures of interest in civil engineering.more » Results from simulations of a reinforced column, highway bridge, multistory building, and nuclear reactor building are presented.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jung, Hyunuk; Kum, Oyeon; Han, Youngyih, E-mail: youngyih@skku.edu

Purpose: In proton therapy, collisions between the patient and nozzle potentially occur because of the large nozzle structure and efforts to minimize the air gap. Thus, software was developed to predict such collisions between the nozzle and patient using treatment virtual simulation. Methods: Three-dimensional (3D) modeling of a gantry inner-floor, nozzle, and robotic-couch was performed using SolidWorks based on the manufacturer’s machine data. To obtain patient body information, a 3D-scanner was utilized right before CT scanning. Using the acquired images, a 3D-image of the patient’s body contour was reconstructed. The accuracy of the image was confirmed against the CT imagemore » of a humanoid phantom. The machine components and the virtual patient were combined on the treatment-room coordinate system, resulting in a virtual simulator. The simulator simulated the motion of its components such as rotation and translation of the gantry, nozzle, and couch in real scale. A collision, if any, was examined both in static and dynamic modes. The static mode assessed collisions only at fixed positions of the machine’s components, while the dynamic mode operated any time a component was in motion. A collision was identified if any voxels of two components, e.g., the nozzle and the patient or couch, overlapped when calculating volume locations. The event and collision point were visualized, and collision volumes were reported. Results: All components were successfully assembled, and the motions were accurately controlled. The 3D-shape of the phantom agreed with CT images within a deviation of 2 mm. Collision situations were simulated within minutes, and the results were displayed and reported. Conclusions: The developed software will be useful in improving patient safety and clinical efficiency of proton therapy.« less

Organizational Learning Goes Virtual?: A Study of Employees' Learning Achievement in Stereoscopic 3D Virtual Reality

ERIC Educational Resources Information Center

Lau, Kung Wong

2015-01-01

Purpose: This study aims to deepen understanding of the use of stereoscopic 3D technology (stereo3D) in facilitating organizational learning. The emergence of advanced virtual technologies, in particular to the stereo3D virtual reality, has fundamentally changed the ways in which organizations train their employees. However, in academic or…

Gaze3DFix: Detecting 3D fixations with an ellipsoidal bounding volume.

PubMed

Weber, Sascha; Schubert, Rebekka S; Vogt, Stefan; Velichkovsky, Boris M; Pannasch, Sebastian

2017-10-26

Nowadays, the use of eyetracking to determine 2-D gaze positions is common practice, and several approaches to the detection of 2-D fixations exist, but ready-to-use algorithms to determine eye movements in three dimensions are still missing. Here we present a dispersion-based algorithm with an ellipsoidal bounding volume that estimates 3D fixations. Therefore, 3D gaze points are obtained using a vector-based approach and are further processed with our algorithm. To evaluate the accuracy of our method, we performed experimental studies with real and virtual stimuli. We obtained good congruence between stimulus position and both the 3D gaze points and the 3D fixation locations within the tested range of 200-600 mm. The mean deviation of the 3D fixations from the stimulus positions was 17 mm for the real as well as for the virtual stimuli, with larger variances at increasing stimulus distances. The described algorithms are implemented in two dynamic linked libraries (Gaze3D.dll and Fixation3D.dll), and we provide a graphical user interface (Gaze3DFixGUI.exe) that is designed for importing 2-D binocular eyetracking data and calculating both 3D gaze points and 3D fixations using the libraries. The Gaze3DFix toolkit, including both libraries and the graphical user interface, is available as open-source software at https://github.com/applied-cognition-research/Gaze3DFix .

Rewritable three-dimensional holographic data storage via optical forces

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yetisen, Ali K., E-mail: ayetisen@mgh.harvard.edu; Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139; Montelongo, Yunuen

2016-08-08

The development of nanostructures that can be reversibly arranged and assembled into 3D patterns may enable optical tunability. However, current dynamic recording materials such as photorefractive polymers cannot be used to store information permanently while also retaining configurability. Here, we describe the synthesis and optimization of a silver nanoparticle doped poly(2-hydroxyethyl methacrylate-co-methacrylic acid) recording medium for reversibly recording 3D holograms. We theoretically and experimentally demonstrate organizing nanoparticles into 3D assemblies in the recording medium using optical forces produced by the gradients of standing waves. The nanoparticles in the recording medium are organized by multiple nanosecond laser pulses to produce reconfigurablemore » slanted multilayer structures. We demonstrate the capability of producing rewritable optical elements such as multilayer Bragg diffraction gratings, 1D photonic crystals, and 3D multiplexed optical gratings. We also show that 3D virtual holograms can be reversibly recorded. This recording strategy may have applications in reconfigurable optical elements, data storage devices, and dynamic holographic displays.« less

3D Graphics Through the Internet: A "Shoot-Out"

NASA Technical Reports Server (NTRS)

Watson, Val; Lasinski, T. A. (Technical Monitor)

1995-01-01

3D graphics through the Internet needs to move beyond the current lowest common denominator of pre-computed movies, which consume bandwidth and are non-interactive. Panelists will demonstrate and compare 3D graphical tools for accessing, analyzing, and collaborating on information through the Internet and World-wide web. The "shoot-out" will illustrate which tools are likely to be the best for the various types of information, including dynamic scientific data, 3-D objects, and virtual environments. The goal of the panel is to encourage more effective use of the Internet by encouraging suppliers and users of information to adopt the next generation of graphical tools.

BoD services in layer 1 VPN with dynamic virtual concatenation group

NASA Astrophysics Data System (ADS)

Du, Shu; Peng, Yunfeng; Long, Keping

2008-11-01

Bandwidth-on-Demand (BoD) services are characteristic of dynamic bandwidth provisioning based on customers' resource requirement, which will be a must for future networks. BoD services become possible with the development of make-before-break, Virtual Concatenation (VCAT) and Link Capacity Adjustment Scheme (LCAS). In this paper, we introduce BoD services into L1VPN, thus the resource assigned to a L1VPN can be gracefully adjusted at various bandwidth granularities based on customers' requirement. And we propose a dynamic bandwidth adjustment scheme, which is compromise between make-before-break and VCAT&LCAS and mainly based on the latter. The scheme minimizes the number of distinct paths to support a connection between a source-destination pair, and uses make-beforebreak technology for re-optimization.

A specification of 3D manipulation in virtual environments

NASA Technical Reports Server (NTRS)

Su, S. Augustine; Furuta, Richard

1994-01-01

In this paper we discuss the modeling of three basic kinds of 3-D manipulations in the context of a logical hand device and our virtual panel architecture. The logical hand device is a useful software abstraction representing hands in virtual environments. The virtual panel architecture is the 3-D component of the 2-D window systems. Both of the abstractions are intended to form the foundation for adaptable 3-D manipulation.

Visualized modeling platform for virtual plant growth and monitoring on the internet

NASA Astrophysics Data System (ADS)

Zhou, De-fu; Tian, Feng-qui; Ren, Ping

2009-07-01

Virtual plant growth is a key research topic in Agriculture Information Technique and Computer Graphics. It has been applied in botany, agronomy, environmental sciences, computre sciences and applied mathematics. Modeling leaf color dynamics in plant is of significant importance for realizing virtual plant growth. Using systematic analysis method and dynamic modeling technology, a SPAD-based leaf color dynamic model was developed to simulate time-course change characters of leaf SPAD on the plant. In addition, process of plant growth can be computer-stimulated using Virtual Reality Modeling Language (VRML) to establish a vivid and visible model, including shooting, rooting, blooming, as well as growth of the stems and leaves. In the resistance environment, e.g., lacking of water, air or nutrient substances, high salt or alkaline, freezing injury, high temperature, suffering from diseases and insect pests, the changes from the level of whole plant to organs, tissues and cells could be computer-stimulated. Changes from physiological and biochemistry could also be described. When a series of indexes were input by the costumers, direct view and microcosmic changes could be shown. Thus, the model has a good performance in predicting growth condition of the plant, laying a foundation for further constructing virtual plant growth system. The results revealed that realistic physiological and pathological processes of 3D virtual plants could be demonstrated by proper design and effectively realized in the internet.

i3Drive, a 3D interactive driving simulator.

PubMed

Ambroz, Miha; Prebil, Ivan

2010-01-01

i3Drive, a wheeled-vehicle simulator, can accurately simulate vehicles of various configurations with up to eight wheels in real time on a desktop PC. It presents the vehicle dynamics as an interactive animation in a virtual 3D environment. The application is fully GUI-controlled, giving users an easy overview of the simulation parameters and letting them adjust those parameters interactively. It models all relevant vehicle systems, including the mechanical models of the suspension, power train, and braking and steering systems. The simulation results generally correspond well with actual measurements, making the system useful for studying vehicle performance in various driving scenarios. i3Drive is thus a worthy complement to other, more complex tools for vehicle-dynamics simulation and analysis.

Virtual reality in radiology: virtual intervention

NASA Astrophysics Data System (ADS)

Harreld, Michael R.; Valentino, Daniel J.; Duckwiler, Gary R.; Lufkin, Robert B.; Karplus, Walter J.

1995-04-01

Intracranial aneurysms are the primary cause of non-traumatic subarachnoid hemorrhage. Morbidity and mortality remain high even with current endovascular intervention techniques. It is presently impossible to identify which aneurysms will grow and rupture, however hemodynamics are thought to play an important role in aneurysm development. With this in mind, we have simulated blood flow in laboratory animals using three dimensional computational fluid dynamics software. The data output from these simulations is three dimensional, complex and transient. Visualization of 3D flow structures with standard 2D display is cumbersome, and may be better performed using a virtual reality system. We are developing a VR-based system for visualization of the computed blood flow and stress fields. This paper presents the progress to date and future plans for our clinical VR-based intervention simulator. The ultimate goal is to develop a software system that will be able to accurately model an aneurysm detected on clinical angiography, visualize this model in virtual reality, predict its future behavior, and give insight into the type of treatment necessary. An associated database will give historical and outcome information on prior aneurysms (including dynamic, structural, and categorical data) that will be matched to any current case, and assist in treatment planning (e.g., natural history vs. treatment risk, surgical vs. endovascular treatment risks, cure prediction, complication rates).

Use of 3D techniques for virtual production

NASA Astrophysics Data System (ADS)

Grau, Oliver; Price, Marc C.; Thomas, Graham A.

2000-12-01

Virtual production for broadcast is currently mainly used in the form of virtual studios, where the resulting media is a sequence of 2D images. With the steady increase of 3D computing power in home PCs and the technical progress in 3D display technology, the content industry is looking for new kinds of program material, which makes use of 3D technology. The applications range form analysis of sport scenes, 3DTV, up to the creation of fully immersive content. In a virtual studio a camera films one or more actors in a controlled environment. The pictures of the actors can be segmented very accurately in real time using chroma keying techniques. The isolated silhouette can be integrated into a new synthetic virtual environment using a studio mixer. The resulting shape description of the actors is 2D so far. For the realization of more sophisticated optical interactions of the actors with the virtual environment, such as occlusions and shadows, an object-based 3D description of scenes is needed. However, the requirements of shape accuracy, and the kind of representation, differ in accordance with the application. This contribution gives an overview of requirements and approaches for the generation of an object-based 3D description in various applications studied by the BBC R and D department. An enhanced Virtual Studio for 3D programs is proposed that covers a range of applications for virtual production.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hayes, Birchard P; Michel, Kelly D; Few, Douglas A

From stereophonic, positional sound to high-definition imagery that is crisp and clean, high fidelity computer graphics enhance our view, insight, and intuition regarding our environments and conditions. Contemporary 3-D modeling tools offer an open architecture framework that enables integration with other technologically innovative arenas. One innovation of great interest is Augmented Reality, the merging of virtual, digital environments with physical, real-world environments creating a mixed reality where relevant data and information augments the real or actual experience in real-time by spatial or semantic context. Pairing 3-D virtual immersive models with a dynamic platform such as semi-autonomous robotics or personnel odometrymore » systems to create a mixed reality offers a new and innovative design information verification inspection capability, evaluation accuracy, and information gathering capability for nuclear facilities. Our paper discusses the integration of two innovative technologies, 3-D visualizations with inertial positioning systems, and the resulting augmented reality offered to the human inspector. The discussion in the paper includes an exploration of human and non-human (surrogate) inspections of a nuclear facility, integrated safeguards knowledge within a synchronized virtual model operated, or worn, by a human inspector, and the anticipated benefits to safeguards evaluations of facility operations.« less

Virtual Diagnostics Interface: Real Time Comparison of Experimental Data and CFD Predictions for a NASA Ares I-Like Vehicle

NASA Technical Reports Server (NTRS)

Schwartz, Richard J.; Fleming, Gary A.

2007-01-01

Virtual Diagnostics Interface technology, or ViDI, is a suite of techniques utilizing image processing, data handling and three-dimensional computer graphics. These techniques aid in the design, implementation, and analysis of complex aerospace experiments. LiveView3D is a software application component of ViDI used to display experimental wind tunnel data in real-time within an interactive, three-dimensional virtual environment. The LiveView3D software application was under development at NASA Langley Research Center (LaRC) for nearly three years. LiveView3D recently was upgraded to perform real-time (as well as post-test) comparisons of experimental data with pre-computed Computational Fluid Dynamics (CFD) predictions. This capability was utilized to compare experimental measurements with CFD predictions of the surface pressure distribution of the NASA Ares I Crew Launch Vehicle (CLV) - like vehicle when tested in the NASA LaRC Unitary Plan Wind Tunnel (UPWT) in December 2006 - January 2007 timeframe. The wind tunnel tests were conducted to develop a database of experimentally-measured aerodynamic performance of the CLV-like configuration for validation of CFD predictive codes.

AVESTAR Center for Operational Excellence of Electricity Generation Plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zitney, Stephen

2012-08-29

To address industry challenges in attaining operational excellence for electricity generation plants, the U.S. Department of Energy’s (DOE) National Energy Technology Laboratory (NETL) has launched a world-class facility for Advanced Virtual Energy Simulation Training and Research (AVESTARTM). This presentation will highlight the AVESTARTM Center simulators, facilities, and comprehensive training, education, and research programs focused on the operation and control of high-efficiency, near-zero-emission electricity generation plants. The AVESTAR Center brings together state-of-the-art, real-time, high-fidelity dynamic simulators with full-scope operator training systems (OTSs) and 3D virtual immersive training systems (ITSs) into an integrated energy plant and control room environment. AVESTAR’s initial offeringmore » combines--for the first time--a “gasification with CO2 capture” process simulator with a “combined-cycle” power simulator together in a single OTS/ITS solution for an integrated gasification combined cycle (IGCC) power plant with carbon dioxide (CO2) capture. IGCC systems are an attractive technology option for power generation, especially when capturing and storing CO2 is necessary to satisfy emission targets. The AVESTAR training program offers a variety of courses that merge classroom learning, simulator-based OTS learning in a control-room operations environment, and immersive learning in the interactive 3D virtual plant environment or ITS. All of the courses introduce trainees to base-load plant operation, control, startups, and shutdowns. Advanced courses require participants to become familiar with coordinated control, fuel switching, power-demand load shedding, and load following, as well as to problem solve equipment and process malfunctions. Designed to ensure work force development, training is offered for control room and plant field operators, as well as engineers and managers. Such comprehensive simulator-based instruction allows for realistic training without compromising worker, equipment, and environmental safety. It also better prepares operators and engineers to manage the plant closer to economic constraints while minimizing or avoiding the impact of any potentially harmful, wasteful, or inefficient events. The AVESTAR Center is also used to augment graduate and undergraduate engineering education in the areas of process simulation, dynamics, control, and safety. Students and researchers gain hands-on simulator-based training experience and learn how the commercial-scale power plants respond dynamically to changes in manipulated inputs, such as coal feed flow rate and power demand. Students also analyze how the regulatory control system impacts power plant performance and stability. In addition, students practice start-up, shutdown, and malfunction scenarios. The 3D virtual ITSs are used for plant familiarization, walk-through, equipment animations, and safety scenarios. To further leverage the AVESTAR facilities and simulators, NETL and its university partners are pursuing an innovative and collaborative R&D program. In the area of process control, AVESTAR researchers are developing enhanced strategies for regulatory control and coordinated plant-wide control, including gasifier and gas turbine lead, as well as advanced process control using model predictive control (MPC) techniques. Other AVESTAR R&D focus areas include high-fidelity equipment modeling using partial differential equations, dynamic reduced order modeling, optimal sensor placement, 3D virtual plant simulation, and modern grid. NETL and its partners plan to continue building the AVESTAR portfolio of dynamic simulators, immersive training systems, and advanced research capabilities to satisfy industry’s growing need for training and experience with the operation and control of clean energy plants. Future dynamic simulators under development include natural gas combined cycle (NGCC) and supercritical pulverized coal (SCPC) plants with post-combustion CO2 capture. These dynamic simulators are targeted for use in establishing a Virtual Carbon Capture Center (VCCC), similar in concept to the DOE’s National Carbon Capture Center for slipstream testing. The VCCC will enable developers of CO2 capture technologies to integrate, test, and optimize the operation of their dynamic capture models within the context of baseline power plant dynamic models. The objective is to provide hands-on, simulator-based “learn-by-operating” test platforms to accelerate the scale-up and deployment of CO2 capture technologies. Future AVESTAR plans also include pursuing R&D on the dynamics, operation, and control of integrated electricity generation and storage systems for the modern grid era. Special emphasis will be given to combining load-following energy plants with renewable and distributed generating supplies and fast-ramping energy storage systems to provide near constant baseload power.« less

Image fusion in craniofacial virtual reality modeling based on CT and 3dMD photogrammetry.

PubMed

Xin, Pengfei; Yu, Hongbo; Cheng, Huanchong; Shen, Shunyao; Shen, Steve G F

2013-09-01

The aim of this study was to demonstrate the feasibility of building a craniofacial virtual reality model by image fusion of 3-dimensional (3D) CT models and 3 dMD stereophotogrammetric facial surface. A CT scan and stereophotography were performed. The 3D CT models were reconstructed by Materialise Mimics software, and the stereophotogrammetric facial surface was reconstructed by 3 dMD patient software. All 3D CT models were exported as Stereo Lithography file format, and the 3 dMD model was exported as Virtual Reality Modeling Language file format. Image registration and fusion were performed in Mimics software. Genetic algorithm was used for precise image fusion alignment with minimum error. The 3D CT models and the 3 dMD stereophotogrammetric facial surface were finally merged into a single file and displayed using Deep Exploration software. Errors between the CT soft tissue model and 3 dMD facial surface were also analyzed. Virtual model based on CT-3 dMD image fusion clearly showed the photorealistic face and bone structures. Image registration errors in virtual face are mainly located in bilateral cheeks and eyeballs, and the errors are more than 1.5 mm. However, the image fusion of whole point cloud sets of CT and 3 dMD is acceptable with a minimum error that is less than 1 mm. The ease of use and high reliability of CT-3 dMD image fusion allows the 3D virtual head to be an accurate, realistic, and widespread tool, and has a great benefit to virtual face model.

Application of physics engines in virtual worlds

NASA Astrophysics Data System (ADS)

Norman, Mark; Taylor, Tim

2002-03-01

Dynamic virtual worlds potentially can provide a much richer and more enjoyable experience than static ones. To realize such worlds, three approaches are commonly used. The first of these, and still widely applied, involves importing traditional animations from a modeling system such as 3D Studio Max. This approach is therefore limited to predefined animation scripts or combinations/blends thereof. The second approach involves the integration of some specific-purpose simulation code, such as car dynamics, and is thus generally limited to one (class of) application(s). The third approach involves the use of general-purpose physics engines, which promise to enable a range of compelling dynamic virtual worlds and to considerably speed up development. By far the largest market today for real-time simulation is computer games, revenues exceeding those of the movie industry. Traditionally, the simulation is produced by game developers in-house for specific titles. However, off-the-shelf middleware physics engines are now available for use in games and related domains. In this paper, we report on our experiences of using middleware physics engines to create a virtual world as an interactive experience, and an advanced scenario where artificial life techniques generate controllers for physically modeled characters.

Visualization of spatial-temporal data based on 3D virtual scene

NASA Astrophysics Data System (ADS)

Wang, Xianghong; Liu, Jiping; Wang, Yong; Bi, Junfang

2009-10-01

The main purpose of this paper is to realize the expression of the three-dimensional dynamic visualization of spatialtemporal data based on three-dimensional virtual scene, using three-dimensional visualization technology, and combining with GIS so that the people's abilities of cognizing time and space are enhanced and improved by designing dynamic symbol and interactive expression. Using particle systems, three-dimensional simulation, virtual reality and other visual means, we can simulate the situations produced by changing the spatial location and property information of geographical entities over time, then explore and analyze its movement and transformation rules by changing the interactive manner, and also replay history and forecast of future. In this paper, the main research object is the vehicle track and the typhoon path and spatial-temporal data, through three-dimensional dynamic simulation of its track, and realize its timely monitoring its trends and historical track replaying; according to visualization techniques of spatialtemporal data in Three-dimensional virtual scene, providing us with excellent spatial-temporal information cognitive instrument not only can add clarity to show spatial-temporal information of the changes and developments in the situation, but also be used for future development and changes in the prediction and deduction.

Quick realization of a ship steering training simulation system by virtual reality

NASA Astrophysics Data System (ADS)

Sun, Jifeng; Zhi, Pinghua; Nie, Weiguo

2003-09-01

This paper addresses two problems of a ship handling simulator. Firstly, 360 scene generation, especially 3D dynamic sea wave modeling, is described. Secondly, a multi-computer complementation of ship handling simulator. This paper also gives the experimental results of the proposed ship handling simulator.

3D Virtual Reality Check: Learner Engagement and Constructivist Theory

ERIC Educational Resources Information Center

Bair, Richard A.

2013-01-01

The inclusion of three-dimensional (3D) virtual tools has created a need to communicate the engagement of 3D tools and specify learning gains that educators and the institutions, which are funding 3D tools, can expect. A review of literature demonstrates that specific models and theories for 3D Virtual Reality (VR) learning do not exist "per…

Combination of virtual screening protocol by in silico towards the discovery of novel 4-hydroxyphenylpyruvate dioxygenase inhibitors

NASA Astrophysics Data System (ADS)

Fu, Ying; Sun, Yi-Na; Yi, Ke-Han; Li, Ming-Qiang; Cao, Hai-Feng; Li, Jia-Zhong; Ye, Fei

2018-02-01

4-Hydroxyphenylpyruvate dioxygenase (EC 1.13.11.27, HPPD) is a potent new bleaching herbicide target. Therefore, in silico structure-based virtual screening was performed in order to speed up the identification of promising HPPD inhibitors. In this study, an integrated virtual screening protocol by combining 3D-pharmacophore model, molecular docking and molecular dynamics (MD) simulation was established to find novel HPPD inhibitors from four commercial databases. 3D-pharmacophore Hypo1 model was applied to efficiently narrow potential hits. The hit compounds were subsequently submitted to molecular docking studies, showing four compounds as potent inhibitor with the mechanism of the Fe(II) coordination and interaction with Phe360, Phe403 and Phe398. MD result demonstrated that nonpolar term of compound 3881 made great contributions to binding affinities. It showed an IC50 being 2.49 µM against AtHPPD in vitro. The results provided useful information for developing novel HPPD inhibitors, leading to further understanding of the interaction mechanism of HPPD inhibitors.

A convertor and user interface to import CAD files into worldtoolkit virtual reality systems

NASA Technical Reports Server (NTRS)

Wang, Peter Hor-Ching

1996-01-01

Virtual Reality (VR) is a rapidly developing human-to-computer interface technology. VR can be considered as a three-dimensional computer-generated Virtual World (VW) which can sense particular aspects of a user's behavior, allow the user to manipulate the objects interactively, and render the VW at real-time accordingly. The user is totally immersed in the virtual world and feel the sense of transforming into that VW. NASA/MSFC Computer Application Virtual Environments (CAVE) has been developing the space-related VR applications since 1990. The VR systems in CAVE lab are based on VPL RB2 system which consists of a VPL RB2 control tower, an LX eyephone, an Isotrak polhemus sensor, two Fastrak polhemus sensors, a folk of Bird sensor, and two VPL DG2 DataGloves. A dynamics animator called Body Electric from VPL is used as the control system to interface with all the input/output devices and to provide the network communications as well as VR programming environment. The RB2 Swivel 3D is used as the modelling program to construct the VW's. A severe limitation of the VPL VR system is the use of RB2 Swivel 3D, which restricts the files to a maximum of 1020 objects and doesn't have the advanced graphics texture mapping. The other limitation is that the VPL VR system is a turn-key system which does not provide the flexibility for user to add new sensors and C language interface. Recently, NASA/MSFC CAVE lab provides VR systems built on Sense8 WorldToolKit (WTK) which is a C library for creating VR development environments. WTK provides device drivers for most of the sensors and eyephones available on the VR market. WTK accepts several CAD file formats, such as Sense8 Neutral File Format, AutoCAD DXF and 3D Studio file format, Wave Front OBJ file format, VideoScape GEO file format, Intergraph EMS stereolithographics and CATIA Stereolithographics STL file formats. WTK functions are object-oriented in their naming convention, are grouped into classes, and provide easy C language interface. Using a CAD or modelling program to build a VW for WTK VR applications, we typically construct the stationary universe with all the geometric objects except the dynamic objects, and create each dynamic object in an individual file.

A three-dimensional virtual environment for modeling mechanical cardiopulmonary interactions.

PubMed

Kaye, J M; Primiano, F P; Metaxas, D N

1998-06-01

We have developed a real-time computer system for modeling mechanical physiological behavior in an interactive, 3-D virtual environment. Such an environment can be used to facilitate exploration of cardiopulmonary physiology, particularly in situations that are difficult to reproduce clinically. We integrate 3-D deformable body dynamics with new, formal models of (scalar) cardiorespiratory physiology, associating the scalar physiological variables and parameters with the corresponding 3-D anatomy. Our framework enables us to drive a high-dimensional system (the 3-D anatomical models) from one with fewer parameters (the scalar physiological models) because of the nature of the domain and our intended application. Our approach is amenable to modeling patient-specific circumstances in two ways. First, using CT scan data, we apply semi-automatic methods for extracting and reconstructing the anatomy to use in our simulations. Second, our scalar physiological models are defined in terms of clinically measurable, patient-specific parameters. This paper describes our approach, problems we have encountered and a sample of results showing normal breathing and acute effects of pneumothoraces.

Architecture of web services in the enhancement of real-time 3D video virtualization in cloud environment

NASA Astrophysics Data System (ADS)

Bada, Adedayo; Wang, Qi; Alcaraz-Calero, Jose M.; Grecos, Christos

2016-04-01

This paper proposes a new approach to improving the application of 3D video rendering and streaming by jointly exploring and optimizing both cloud-based virtualization and web-based delivery. The proposed web service architecture firstly establishes a software virtualization layer based on QEMU (Quick Emulator), an open-source virtualization software that has been able to virtualize system components except for 3D rendering, which is still in its infancy. The architecture then explores the cloud environment to boost the speed of the rendering at the QEMU software virtualization layer. The capabilities and inherent limitations of Virgil 3D, which is one of the most advanced 3D virtual Graphics Processing Unit (GPU) available, are analyzed through benchmarking experiments and integrated into the architecture to further speed up the rendering. Experimental results are reported and analyzed to demonstrate the benefits of the proposed approach.

3D Technology Selection for a Virtual Learning Environment by Blending ISO 9126 Standard and AHP

ERIC Educational Resources Information Center

Cetin, Aydin; Guler, Inan

2011-01-01

Web3D presents many opportunities for learners in a virtual world or virtual environment over the web. This is a great opportunity for open-distance education institutions to benefit from web3d technologies to create courses with interactive 3d materials. There are many open source and commercial products offering 3d technologies over the web…

VRLane: a desktop virtual safety management program for underground coal mine

NASA Astrophysics Data System (ADS)

Li, Mei; Chen, Jingzhu; Xiong, Wei; Zhang, Pengpeng; Wu, Daozheng

2008-10-01

VR technologies, which generate immersive, interactive, and three-dimensional (3D) environments, are seldom applied to coal mine safety work management. In this paper, a new method that combined the VR technologies with underground mine safety management system was explored. A desktop virtual safety management program for underground coal mine, called VRLane, was developed. The paper mainly concerned about the current research advance in VR, system design, key techniques and system application. Two important techniques were introduced in the paper. Firstly, an algorithm was designed and implemented, with which the 3D laneway models and equipment models can be built on the basis of the latest mine 2D drawings automatically, whereas common VR programs established 3D environment by using 3DS Max or the other 3D modeling software packages with which laneway models were built manually and laboriously. Secondly, VRLane realized system integration with underground industrial automation. VRLane not only described a realistic 3D laneway environment, but also described the status of the coal mining, with functions of displaying the run states and related parameters of equipment, per-alarming the abnormal mining events, and animating mine cars, mine workers, or long-wall shearers. The system, with advantages of cheap, dynamic, easy to maintenance, provided a useful tool for safety production management in coal mine.

Interactive floating windows: a new technique for stereoscopic video games

NASA Astrophysics Data System (ADS)

Zerebecki, Chris; Stanfield, Brodie; Tawadrous, Mina; Buckstein, Daniel; Hogue, Andrew; Kapralos, Bill

2012-03-01

The film industry has a long history of creating compelling experiences in stereoscopic 3D. Recently, the video game as an artistic medium has matured into an effective way to tell engaging and immersive stories. Given the current push to bring stereoscopic 3D technology into the consumer market there is considerable interest to develop stereoscopic 3D video games. Game developers have largely ignored the need to design their games specifically for stereoscopic 3D and have thus relied on automatic conversion and driver technology. Game developers need to evaluate solutions used in other media, such as film, to correct perceptual problems such as window violations, and modify or create new solutions to work within an interactive framework. In this paper we extend the dynamic floating window technique into the interactive domain enabling the player to position a virtual window in space. Interactively changing the position, size, and the 3D rotation of the virtual window, objects can be made to 'break the mask' dramatically enhancing the stereoscopic effect. By demonstrating that solutions from the film industry can be extended into the interactive space, it is our hope that this initiates further discussion in the game development community to strengthen their story-telling mechanisms in stereoscopic 3D games.

CROSS DRIVE: A New Interactive and Immersive Approach for Exploring 3D Time-Dependent Mars Atmospheric Data in Distributed Teams

NASA Astrophysics Data System (ADS)

Gerndt, Andreas M.; Engelke, Wito; Giuranna, Marco; Vandaele, Ann C.; Neary, Lori; Aoki, Shohei; Kasaba, Yasumasa; Garcia, Arturo; Fernando, Terrence; Roberts, David; CROSS DRIVE Team

2016-10-01

Atmospheric phenomena of Mars can be highly dynamic and have daily and seasonal variations. Planetary-scale wavelike disturbances, for example, are frequently observed in Mars' polar winter atmosphere. Possible sources of the wave activity were suggested to be dynamical instabilities and quasi-stationary planetary waves, i.e. waves that arise predominantly via zonally asymmetric surface properties. For a comprehensive understanding of these phenomena, single layers of altitude have to be analyzed carefully and relations between different atmospheric quantities and interaction with the surface of Mars have to be considered. The CROSS DRIVE project tries to address the presentation of those data with a global view by means of virtual reality techniques. Complex orbiter data from spectrometer and observation data from Earth are combined with global circulation models and high-resolution terrain data and images available from Mars Express or MRO instruments. Scientists can interactively extract features from those dataset and can change visualization parameters in real-time in order to emphasize findings. Stereoscopic views allow for perception of the actual 3D behavior of Mars's atmosphere. A very important feature of the visualization system is the possibility to connect distributed workspaces together. This enables discussions between distributed working groups. The workspace can scale from virtual reality systems to expert desktop applications to web-based project portals. If multiple virtual environments are connected, the 3D position of each individual user is captured and used to depict the scientist as an avatar in the virtual world. The appearance of the avatar can also scale from simple annotations to complex avatars using tele-presence technology to reconstruct the users in 3D. Any change of the feature set (annotations, cutplanes, volume rendering, etc.) within the VR is immediately exchanged between all connected users. This allows that everybody is always aware of what is visible and discussed. The discussion is supported by audio and interaction is controlled by a moderator managing turn-taking presentations. A use case execution proved a success and showed the potential of this immersive approach.

High-fidelity simulation capability for virtual testing of seismic and acoustic sensors

NASA Astrophysics Data System (ADS)

Wilson, D. Keith; Moran, Mark L.; Ketcham, Stephen A.; Lacombe, James; Anderson, Thomas S.; Symons, Neill P.; Aldridge, David F.; Marlin, David H.; Collier, Sandra L.; Ostashev, Vladimir E.

2005-05-01

This paper describes development and application of a high-fidelity, seismic/acoustic simulation capability for battlefield sensors. The purpose is to provide simulated sensor data so realistic that they cannot be distinguished by experts from actual field data. This emerging capability provides rapid, low-cost trade studies of unattended ground sensor network configurations, data processing and fusion strategies, and signatures emitted by prototype vehicles. There are three essential components to the modeling: (1) detailed mechanical signature models for vehicles and walkers, (2) high-resolution characterization of the subsurface and atmospheric environments, and (3) state-of-the-art seismic/acoustic models for propagating moving-vehicle signatures through realistic, complex environments. With regard to the first of these components, dynamic models of wheeled and tracked vehicles have been developed to generate ground force inputs to seismic propagation models. Vehicle models range from simple, 2D representations to highly detailed, 3D representations of entire linked-track suspension systems. Similarly detailed models of acoustic emissions from vehicle engines are under development. The propagation calculations for both the seismics and acoustics are based on finite-difference, time-domain (FDTD) methodologies capable of handling complex environmental features such as heterogeneous geologies, urban structures, surface vegetation, and dynamic atmospheric turbulence. Any number of dynamic sources and virtual sensors may be incorporated into the FDTD model. The computational demands of 3D FDTD simulation over tactical distances require massively parallel computers. Several example calculations of seismic/acoustic wave propagation through complex atmospheric and terrain environments are shown.

Clinically Normal Stereopsis Does Not Ensure Performance Benefit from Stereoscopic 3D Depth Cues

DTIC Science & Technology

2014-10-28

Stereopsis, Binocular Vision, Optometry , Depth Perception, 3D vision, 3D human factors, Stereoscopic displays, S3D, Virtual environment 16...Binocular Vision, Optometry , Depth Perception, 3D vision, 3D human factors, Stereoscopic displays, S3D, Virtual environment 1 Distribution A: Approved

A new dynamic 3D virtual methodology for teaching the mechanics of atrial septation as seen in the human heart.

PubMed

Schleich, Jean-Marc; Dillenseger, Jean-Louis; Houyel, Lucile; Almange, Claude; Anderson, Robert H

2009-01-01

Learning embryology remains difficult, since it requires understanding of many complex phenomena. The temporal evolution of developmental events has classically been illustrated using cartoons, which create difficulty in linking spatial and temporal aspects, such correlation being the keystone of descriptive embryology. We synthesized the bibliographic data from recent studies of atrial septal development. On the basis of this synthesis, consensus on the stages of atrial septation as seen in the human heart has been reached by a group of experts in cardiac embryology and pediatric cardiology. This has permitted the preparation of three-dimensional (3D) computer graphic objects for the anatomical components involved in the different stages of normal human atrial septation. We have provided a virtual guide to the process of normal atrial septation, the animation providing an appreciation of the temporal and morphologic events necessary to separate the systemic and pulmonary venous returns. We have shown that our animations of normal human atrial septation increase significantly the teaching of the complex developmental processes involved, and provide a new dynamic for the process of learning.

Interaction Design and Usability of Learning Spaces in 3D Multi-user Virtual Worlds

NASA Astrophysics Data System (ADS)

Minocha, Shailey; Reeves, Ahmad John

Three-dimensional virtual worlds are multimedia, simulated environments, often managed over the Web, which users can 'inhabit' and interact via their own graphical, self-representations known as 'avatars'. 3D virtual worlds are being used in many applications: education/training, gaming, social networking, marketing and commerce. Second Life is the most widely used 3D virtual world in education. However, problems associated with usability, navigation and way finding in 3D virtual worlds may impact on student learning and engagement. Based on empirical investigations of learning spaces in Second Life, this paper presents design guidelines to improve the usability and ease of navigation in 3D spaces. Methods of data collection include semi-structured interviews with Second Life students, educators and designers. The findings have revealed that design principles from the fields of urban planning, Human- Computer Interaction, Web usability, geography and psychology can influence the design of spaces in 3D multi-user virtual environments.

High-immersion three-dimensional display of the numerical computer model

NASA Astrophysics Data System (ADS)

Xing, Shujun; Yu, Xunbo; Zhao, Tianqi; Cai, Yuanfa; Chen, Duo; Chen, Zhidong; Sang, Xinzhu

2013-08-01

High-immersion three-dimensional (3D) displays making them valuable tools for many applications, such as designing and constructing desired building houses, industrial architecture design, aeronautics, scientific research, entertainment, media advertisement, military areas and so on. However, most technologies provide 3D display in the front of screens which are in parallel with the walls, and the sense of immersion is decreased. To get the right multi-view stereo ground image, cameras' photosensitive surface should be parallax to the public focus plane and the cameras' optical axes should be offset to the center of public focus plane both atvertical direction and horizontal direction. It is very common to use virtual cameras, which is an ideal pinhole camera to display 3D model in computer system. We can use virtual cameras to simulate the shooting method of multi-view ground based stereo image. Here, two virtual shooting methods for ground based high-immersion 3D display are presented. The position of virtual camera is determined by the people's eye position in the real world. When the observer stand in the circumcircle of 3D ground display, offset perspective projection virtual cameras is used. If the observer stands out the circumcircle of 3D ground display, offset perspective projection virtual cameras and the orthogonal projection virtual cameras are adopted. In this paper, we mainly discussed the parameter setting of virtual cameras. The Near Clip Plane parameter setting is the main point in the first method, while the rotation angle of virtual cameras is the main point in the second method. In order to validate the results, we use the D3D and OpenGL to render scenes of different viewpoints and generate a stereoscopic image. A realistic visualization system for 3D models is constructed and demonstrated for viewing horizontally, which provides high-immersion 3D visualization. The displayed 3D scenes are compared with the real objects in the real world.

Research on Visualization of Ground Laser Radar Data Based on Osg

NASA Astrophysics Data System (ADS)

Huang, H.; Hu, C.; Zhang, F.; Xue, H.

2018-04-01

Three-dimensional (3D) laser scanning is a new advanced technology integrating light, machine, electricity, and computer technologies. It can conduct 3D scanning to the whole shape and form of space objects with high precision. With this technology, you can directly collect the point cloud data of a ground object and create the structure of it for rendering. People use excellent 3D rendering engine to optimize and display the 3D model in order to meet the higher requirements of real time realism rendering and the complexity of the scene. OpenSceneGraph (OSG) is an open source 3D graphics engine. Compared with the current mainstream 3D rendering engine, OSG is practical, economical, and easy to expand. Therefore, OSG is widely used in the fields of virtual simulation, virtual reality, science and engineering visualization. In this paper, a dynamic and interactive ground LiDAR data visualization platform is constructed based on the OSG and the cross-platform C++ application development framework Qt. In view of the point cloud data of .txt format and the triangulation network data file of .obj format, the functions of 3D laser point cloud and triangulation network data display are realized. It is proved by experiments that the platform is of strong practical value as it is easy to operate and provides good interaction.

iVirtualWorld: A Domain-Oriented End-User Development Environment for Building 3D Virtual Chemistry Experiments

ERIC Educational Resources Information Center

Zhong, Ying

2013-01-01

Virtual worlds are well-suited for building virtual laboratories for educational purposes to complement hands-on physical laboratories. However, educators may face technical challenges because developing virtual worlds requires skills in programming and 3D design. Current virtual world building tools are developed for users who have programming…

Improving Big Data Visual Analytics with Interactive Virtual Reality

DTIC Science & Technology

2015-05-22

gain a better understanding of data include scalable zooms, dynamic filtering, and anno - tation. Below, we describe some tasks that can be performed...pages 609–614. IEEE, 2014. [13] Matt R Fetterman, Zachary J Weber, Robert Freking, Alessio Volpe, D Scott, et al. Luminocity: a 3d printed, illuminated...Institute for Business Valueexecutive report, IBM Institute for Business Value, 2012. [24] James J Thomas. Illuminating the path:[the research and

3D Inhabited Virtual Worlds: Interactivity and Interaction between Avatars, Autonomous Agents, and Users.

ERIC Educational Resources Information Center

Jensen, Jens F.

This paper addresses some of the central questions currently related to 3-Dimensional Inhabited Virtual Worlds (3D-IVWs), their virtual interactions, and communication, drawing from the theory and methodology of sociology, interaction analysis, interpersonal communication, semiotics, cultural studies, and media studies. First, 3D-IVWs--seen as a…

Virtual Resting Pd/Pa From Coronary Angiography and Blood Flow Modelling: Diagnostic Performance Against Fractional Flow Reserve.

PubMed

Papafaklis, Michail I; Muramatsu, Takashi; Ishibashi, Yuki; Bourantas, Christos V; Fotiadis, Dimitrios I; Brilakis, Emmanouil S; Garcia-Garcia, Héctor M; Escaned, Javier; Serruys, Patrick W; Michalis, Lampros K

2018-03-01

Fractional flow reserve (FFR) has been established as a useful diagnostic tool. The distal coronary pressure to aortic pressure (Pd/Pa) ratio at rest is a simpler physiologic index but also requires the use of the pressure wire, whereas recently proposed virtual functional indices derived from coronary imaging require complex blood flow modelling and/or are time-consuming. Our aim was to test the diagnostic performance of virtual resting Pd/Pa using routine angiographic images and a simple flow model. Three-dimensional quantitative coronary angiography (3D-QCA) was performed in 139 vessels (120 patients) with intermediate lesions assessed by FFR. The resting Pd/Pa for each lesion was assessed by computational fluid dynamics. The discriminatory power of virtual resting Pd/Pa against FFR (reference: ≤0.80) was high (area under the receiver operator characteristic curve [AUC]: 90.5% [95% CI: 85.4-95.6%]). Diagnostic accuracy, sensitivity and specificity for the optimal virtual resting Pd/Pa cut-off (≤0.94) were 84.9%, 90.4% and 81.6%, respectively. Virtual resting Pd/Pa demonstrated superior performance (p<0.001) versus 3D-QCA %area stenosis (AUC: 77.5% [95% CI: 69.8-85.3%]). There was a good correlation between virtual resting Pd/Pa and FFR (r=0.69, p<0.001). Virtual resting Pd/Pa using routine angiographic data and a simple flow model provides fast functional assessment of coronary lesions without requiring the pressure-wire and hyperaemia induction. The high diagnostic performance of virtual resting Pd/Pa for predicting FFR shows promise for using this simple/fast virtual index in clinical practice. Copyright © 2017 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zitney, S.E.

This presentation will examine process systems engineering R&D needs for application to advanced fossil energy (FE) systems and highlight ongoing research activities at the National Energy Technology Laboratory (NETL) under the auspices of a recently launched Collaboratory for Process & Dynamic Systems Research. The three current technology focus areas include: 1) High-fidelity systems with NETL's award-winning Advanced Process Engineering Co-Simulator (APECS) technology for integrating process simulation with computational fluid dynamics (CFD) and virtual engineering concepts, 2) Dynamic systems with R&D on plant-wide IGCC dynamic simulation, control, and real-time training applications, and 3) Systems optimization including large-scale process optimization, stochastic simulationmore » for risk/uncertainty analysis, and cost estimation. Continued R&D aimed at these and other key process systems engineering models, methods, and tools will accelerate the development of advanced gasification-based FE systems and produce increasingly valuable outcomes for DOE and the Nation.« less

Short-term EEG dynamics and neural generators evoked by navigational images

PubMed Central

Leroy, Axelle; Cevallos, Carlos; Cebolla, Ana-Maria; Caharel, Stéphanie; Dan, Bernard

2017-01-01

The ecological environment offered by virtual reality is primarily supported by visual information. The different image contents and their rhythmic presentation imply specific bottom-up and top-down processing. Because these processes already occur during passive observation we studied the brain responses evoked by the presentation of specific 3D virtual tunnels with respect to 2D checkerboard. For this, we characterized electroencephalograhy dynamics (EEG), the evoked potentials and related neural generators involved in various visual paradigms. Time-frequency analysis showed modulation of alpha-beta oscillations indicating the presence of stronger prediction and after-effects of the 3D-tunnel with respect to the checkerboard. Whatever the presented image, the generators of the P100 were situated bilaterally in the occipital cortex (BA18, BA19) and in the right inferior temporal cortex (BA20). In checkerboard but not 3D-tunnel presentation, the left fusiform gyrus (BA37) was additionally recruited. P200 generators were situated in the temporal cortex (BA21) and the cerebellum (lobule VI/Crus I) specifically for the checkerboard while the right parahippocampal gyrus (BA36) and the cerebellum (lobule IV/V and IX/X) were involved only during the 3D-tunnel presentation. For both type of image, P300 generators were localized in BA37 but also in BA19, the right BA21 and the cerebellar lobule VI for only the checkerboard and the left BA20-BA21 for only the 3D-tunnel. Stronger P300 delta-theta oscillations recorded in this later situation point to a prevalence of the effect of changing direction over the proper visual content of the 3D-tunnel. The parahippocampal gyrus (BA36) implicated in navigation was also identified when the 3D-tunnel was compared to their scrambled versions, highlighting an action-oriented effect linked to navigational content. PMID:28632774

AGGRESCAN3D (A3D): server for prediction of aggregation properties of protein structures

PubMed Central

Zambrano, Rafael; Jamroz, Michal; Szczasiuk, Agata; Pujols, Jordi; Kmiecik, Sebastian; Ventura, Salvador

2015-01-01

Protein aggregation underlies an increasing number of disorders and constitutes a major bottleneck in the development of therapeutic proteins. Our present understanding on the molecular determinants of protein aggregation has crystalized in a series of predictive algorithms to identify aggregation-prone sites. A majority of these methods rely only on sequence. Therefore, they find difficulties to predict the aggregation properties of folded globular proteins, where aggregation-prone sites are often not contiguous in sequence or buried inside the native structure. The AGGRESCAN3D (A3D) server overcomes these limitations by taking into account the protein structure and the experimental aggregation propensity scale from the well-established AGGRESCAN method. Using the A3D server, the identified aggregation-prone residues can be virtually mutated to design variants with increased solubility, or to test the impact of pathogenic mutations. Additionally, A3D server enables to take into account the dynamic fluctuations of protein structure in solution, which may influence aggregation propensity. This is possible in A3D Dynamic Mode that exploits the CABS-flex approach for the fast simulations of flexibility of globular proteins. The A3D server can be accessed at http://biocomp.chem.uw.edu.pl/A3D/. PMID:25883144

Virtual 3d City Modeling: Techniques and Applications

NASA Astrophysics Data System (ADS)

Singh, S. P.; Jain, K.; Mandla, V. R.

2013-08-01

3D city model is a digital representation of the Earth's surface and it's related objects such as Building, Tree, Vegetation, and some manmade feature belonging to urban area. There are various terms used for 3D city models such as "Cybertown", "Cybercity", "Virtual City", or "Digital City". 3D city models are basically a computerized or digital model of a city contains the graphic representation of buildings and other objects in 2.5 or 3D. Generally three main Geomatics approach are using for Virtual 3-D City models generation, in first approach, researcher are using Conventional techniques such as Vector Map data, DEM, Aerial images, second approach are based on High resolution satellite images with LASER scanning, In third method, many researcher are using Terrestrial images by using Close Range Photogrammetry with DSM & Texture mapping. We start this paper from the introduction of various Geomatics techniques for 3D City modeling. These techniques divided in to two main categories: one is based on Automation (Automatic, Semi-automatic and Manual methods), and another is Based on Data input techniques (one is Photogrammetry, another is Laser Techniques). After details study of this, finally in short, we are trying to give the conclusions of this study. In the last, we are trying to give the conclusions of this research paper and also giving a short view for justification and analysis, and present trend for 3D City modeling. This paper gives an overview about the Techniques related with "Generation of Virtual 3-D City models using Geomatics Techniques" and the Applications of Virtual 3D City models. Photogrammetry, (Close range, Aerial, Satellite), Lasergrammetry, GPS, or combination of these modern Geomatics techniques play a major role to create a virtual 3-D City model. Each and every techniques and method has some advantages and some drawbacks. Point cloud model is a modern trend for virtual 3-D city model. Photo-realistic, Scalable, Geo-referenced virtual 3-D City model is a very useful for various kinds of applications such as for planning in Navigation, Tourism, Disasters Management, Transportations, Municipality, Urban Environmental Managements and Real-estate industry. So the Construction of Virtual 3-D city models is a most interesting research topic in recent years.

Applying a 3D Situational Virtual Learning Environment to the Real World Business--An Extended Research in Marketing

ERIC Educational Resources Information Center

Wang, Shwu-huey

2012-01-01

In order to understand (1) what kind of students can be facilitated through the help of three-dimensional virtual learning environment (3D VLE), and (2) the relationship between a conventional test (ie, paper and pencil test) and the 3D VLE used in this study, the study designs a 3D virtual supermarket (3DVS) to help students transform their role…

The Virtual Radiopharmacy Laboratory: A 3-D Simulation for Distance Learning

ERIC Educational Resources Information Center

Alexiou, Antonios; Bouras, Christos; Giannaka, Eri; Kapoulas, Vaggelis; Nani, Maria; Tsiatsos, Thrasivoulos

2004-01-01

This article presents Virtual Radiopharmacy Laboratory (VR LAB), a virtual laboratory accessible through the Internet. VR LAB is designed and implemented in the framework of the VirRAD European project. This laboratory represents a 3D simulation of a radio-pharmacy laboratory, where learners, represented by 3D avatars, can experiment on…

The Use of Physical and Virtual Manipulatives in an Undergraduate Mechanical Engineering (Dynamics) Course

ERIC Educational Resources Information Center

Pan, Edward A.

2013-01-01

Science, technology, engineering, and mathematics (STEM) education is a national focus. Engineering education, as part of STEM education, needs to adapt to meet the needs of the nation in a rapidly changing world. Using computer-based visualization tools and corresponding 3D printed physical objects may help nontraditional students succeed in…

A New Dynamic 3D Virtual Methodology for Teaching the Mechanics of Atrial Septation as Seen in the Human Heart

ERIC Educational Resources Information Center

Schleich, Jean-Marc; Dillenseger, Jean-Louis; Houyel, Lucile; Almange, Claude; Anderson, Robert H.

2009-01-01

Learning embryology remains difficult, since it requires understanding of many complex phenomena. The temporal evolution of developmental events has classically been illustrated using cartoons, which create difficulty in linking spatial and temporal aspects, such correlation being the keystone of descriptive embryology. We synthesized the…

DigBody®: A new 3D modeling tool for nasal virtual surgery.

PubMed

Burgos, M A; Sanmiguel-Rojas, E; Singh, Narinder; Esteban-Ortega, F

2018-07-01

Recent studies have demonstrated that a significant number of surgical procedures for nasal airway obstruction (NAO) have a high rate of surgical failure. In part, this problem is due to the lack of reliable objective clinical parameters to aid surgeons during preoperative planning. Modeling tools that allow virtual surgery to be performed do exist, but all require direct manipulation of computed tomography (CT) or magnetic resonance imaging (MRI) data. Specialists in Rhinology have criticized these tools for their complex user interface, and have requested more intuitive, user-friendly and powerful software to make virtual surgery more accessible and realistic. In this paper we present a new virtual surgery software tool, DigBody ® . This new surgery module is integrated into the computational fluid dynamics (CFD) program MeComLand ® , which was developed exclusively to analyze nasal airflow. DigBody ® works directly with a 3D nasal model that mimics real surgery. Furthermore, this surgery module permits direct assessment of the operated cavity following virtual surgery by CFD simulation. The effectiveness of DigBody ® has been demonstrated by real surgery on two patients based on prior virtual operation results. Both subjects experienced excellent surgical outcomes with no residual nasal obstruction. This tool has great potential to aid surgeons in modeling potential surgical maneuvers, minimizing complications, and being confident that patients will receive optimal postoperative outcomes, validated by personalized CFD testing. Copyright © 2018 Elsevier Ltd. All rights reserved.

3D Flow visualization in virtual reality

NASA Astrophysics Data System (ADS)

Pietraszewski, Noah; Dhillon, Ranbir; Green, Melissa

2017-11-01

By viewing fluid dynamic isosurfaces in virtual reality (VR), many of the issues associated with the rendering of three-dimensional objects on a two-dimensional screen can be addressed. In addition, viewing a variety of unsteady 3D data sets in VR opens up novel opportunities for education and community outreach. In this work, the vortex wake of a bio-inspired pitching panel was visualized using a three-dimensional structural model of Q-criterion isosurfaces rendered in virtual reality using the HTC Vive. Utilizing the Unity cross-platform gaming engine, a program was developed to allow the user to control and change this model's position and orientation in three-dimensional space. In addition to controlling the model's position and orientation, the user can ``scroll'' forward and backward in time to analyze the formation and shedding of vortices in the wake. Finally, the user can toggle between different quantities, while keeping the time step constant, to analyze flow parameter relationships at specific times during flow development. The information, data, or work presented herein was funded in part by an award from NYS Department of Economic Development (DED) through the Syracuse Center of Excellence.

Novel interactive virtual showcase based on 3D multitouch technology

NASA Astrophysics Data System (ADS)

Yang, Tao; Liu, Yue; Lu, You; Wang, Yongtian

2009-11-01

A new interactive virtual showcase is proposed in this paper. With the help of virtual reality technology, the user of the proposed system can watch the virtual objects floating in the air from all four sides and interact with the virtual objects by touching the four surfaces of the virtual showcase. Unlike traditional multitouch system, this system cannot only realize multi-touch on a plane to implement 2D translation, 2D scaling, and 2D rotation of the objects; it can also realize the 3D interaction of the virtual objects by recognizing and analyzing the multi-touch that can be simultaneously captured from the four planes. Experimental results show the potential of the proposed system to be applied in the exhibition of historical relics and other precious goods.

Application of computer virtual simulation technology in 3D animation production

NASA Astrophysics Data System (ADS)

Mo, Can

2017-11-01

In the continuous development of computer technology, the application system of virtual simulation technology has been further optimized and improved. It also has been widely used in various fields of social development, such as city construction, interior design, industrial simulation and tourism teaching etc. This paper mainly introduces the virtual simulation technology used in 3D animation. Based on analyzing the characteristics of virtual simulation technology, the application ways and means of this technology in 3D animation are researched. The purpose is to provide certain reference for the 3D effect promotion days after.

Creation of a 3-dimensional virtual dental patient for computer-guided surgery and CAD-CAM interim complete removable and fixed dental prostheses: A clinical report.

PubMed

Harris, Bryan T; Montero, Daniel; Grant, Gerald T; Morton, Dean; Llop, Daniel R; Lin, Wei-Shao

2017-02-01

This clinical report proposes a digital workflow using 2-dimensional (2D) digital photographs, a 3D extraoral facial scan, and cone beam computed tomography (CBCT) volumetric data to create a 3D virtual patient with craniofacial hard tissue, remaining dentition (including surrounding intraoral soft tissue), and the realistic appearance of facial soft tissue at an exaggerated smile under static conditions. The 3D virtual patient was used to assist the virtual diagnostic tooth arrangement process, providing patient with a pleasing preoperative virtual smile design that harmonized with facial features. The 3D virtual patient was also used to gain patient's pretreatment approval (as a communication tool), design a prosthetically driven surgical plan for computer-guided implant surgery, and fabricate the computer-aided design and computer-aided manufacturing (CAD-CAM) interim prostheses. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Designing Virtual Museum Using Web3D Technology

NASA Astrophysics Data System (ADS)

Zhao, Jianghai

VRT was born to have the potentiality of constructing an effective learning environment due to its 3I characteristics: Interaction, Immersion and Imagination. It is now applied in education in a more profound way along with the development of VRT. Virtual Museum is one of the applications. The Virtual Museum is based on the WEB3D technology and extensibility is the most important factor. Considering the advantage and disadvantage of each WEB3D technology, VRML, CULT3D AND VIEWPOINT technologies are chosen. A web chatroom based on flash and ASP technology is also been created in order to make the Virtual Museum an interactive learning environment.

3D Virtual Learning Environments in Education: A Meta-Review

ERIC Educational Resources Information Center

Reisoglu, I.; Topu, B.; Yilmaz, R.; Karakus Yilmaz, T.; Göktas, Y.

2017-01-01

The aim of this study is to investigate recent empirical research studies about 3D virtual learning environments. A total of 167 empirical studies that involve the use of 3D virtual worlds in education were examined by meta-review. Our findings show that the "Second Life" platform has been frequently used in studies. Among the reviewed…

Learning in 3D Virtual Environments: Collaboration and Knowledge Spirals

ERIC Educational Resources Information Center

Burton, Brian G.; Martin, Barbara N.

2010-01-01

The purpose of this case study was to determine if learning occurred within a 3D virtual learning environment by determining if elements of collaboration and Nonaka and Takeuchi's (1995) knowledge spiral were present. A key portion of this research was the creation of a Virtual Learning Environment. This 3D VLE utilized the Torque Game Engine…

An interactive three-dimensional virtual body structures system for anatomical training over the internet.

PubMed

Temkin, Bharti; Acosta, Eric; Malvankar, Ameya; Vaidyanath, Sreeram

2006-04-01

The Visible Human digital datasets make it possible to develop computer-based anatomical training systems that use virtual anatomical models (virtual body structures-VBS). Medical schools are combining these virtual training systems and classical anatomy teaching methods that use labeled images and cadaver dissection. In this paper we present a customizable web-based three-dimensional anatomy training system, W3D-VBS. W3D-VBS uses National Library of Medicine's (NLM) Visible Human Male datasets to interactively locate, explore, select, extract, highlight, label, and visualize, realistic 2D (using axial, coronal, and sagittal views) and 3D virtual structures. A real-time self-guided virtual tour of the entire body is designed to provide detailed anatomical information about structures, substructures, and proximal structures. The system thus facilitates learning of visuospatial relationships at a level of detail that may not be possible by any other means. The use of volumetric structures allows for repeated real-time virtual dissections, from any angle, at the convenience of the user. Volumetric (3D) virtual dissections are performed by adding, removing, highlighting, and labeling individual structures (and/or entire anatomical systems). The resultant virtual explorations (consisting of anatomical 2D/3D illustrations and animations), with user selected highlighting colors and label positions, can be saved and used for generating lesson plans and evaluation systems. Tracking users' progress using the evaluation system helps customize the curriculum, making W3D-VBS a powerful learning tool. Our plan is to incorporate other Visible Human segmented datasets, especially datasets with higher resolutions, that make it possible to include finer anatomical structures such as nerves and small vessels. (c) 2006 Wiley-Liss, Inc.

Timing of three-dimensional virtual treatment planning of orthognathic surgery: a prospective single-surgeon evaluation on 350 consecutive cases.

PubMed

Swennen, Gwen R J

2014-11-01

The purpose of this article is to evaluate the timing for three-dimensional (3D) virtual treatment planning of orthognathic surgery in the daily clinical routine. A total of 350 consecutive patients were included in this study. All patients were scanned following the standardized "Triple CBCT Scan Protocol" in centric relation. Integrated 3D virtual planning and actual surgery were performed by the same surgeon in all patients. Although clinically acceptable, still software improvements especially toward 3D virtual occlusal definition are mandatory to make 3D virtual planning of orthognathic surgery less time-consuming and more user-friendly to the clinician. Copyright © 2014 Elsevier Inc. All rights reserved.

Innovative application of virtual display technique in virtual museum

NASA Astrophysics Data System (ADS)

Zhang, Jiankang

2017-09-01

Virtual museum refers to display and simulate the functions of real museum on the Internet in the form of 3 Dimensions virtual reality by applying interactive programs. Based on Virtual Reality Modeling Language, virtual museum building and its effective interaction with the offline museum lie in making full use of 3 Dimensions panorama technique, virtual reality technique and augmented reality technique, and innovatively taking advantages of dynamic environment modeling technique, real-time 3 Dimensions graphics generating technique, system integration technique and other key virtual reality techniques to make sure the overall design of virtual museum.3 Dimensions panorama technique, also known as panoramic photography or virtual reality, is a technique based on static images of the reality. Virtual reality technique is a kind of computer simulation system which can create and experience the interactive 3 Dimensions dynamic visual world. Augmented reality, also known as mixed reality, is a technique which simulates and mixes the information (visual, sound, taste, touch, etc.) that is difficult for human to experience in reality. These technologies make virtual museum come true. It will not only bring better experience and convenience to the public, but also be conducive to improve the influence and cultural functions of the real museum.

Virtual Reality: The Future of Animated Virtual Instructor, the Technology and Its Emergence to a Productive E-Learning Environment.

ERIC Educational Resources Information Center

Jiman, Juhanita

This paper discusses the use of Virtual Reality (VR) in e-learning environments where an intelligent three-dimensional (3D) virtual person plays the role of an instructor. With the existence of this virtual instructor, it is hoped that the teaching and learning in the e-environment will be more effective and productive. This virtual 3D animated…

Development of visual 3D virtual environment for control software

NASA Technical Reports Server (NTRS)

Hirose, Michitaka; Myoi, Takeshi; Amari, Haruo; Inamura, Kohei; Stark, Lawrence

1991-01-01

Virtual environments for software visualization may enable complex programs to be created and maintained. A typical application might be for control of regional electric power systems. As these encompass broader computer networks than ever, construction of such systems becomes very difficult. Conventional text-oriented environments are useful in programming individual processors. However, they are obviously insufficient to program a large and complicated system, that includes large numbers of computers connected to each other; such programming is called 'programming in the large.' As a solution for this problem, the authors are developing a graphic programming environment wherein one can visualize complicated software in virtual 3D world. One of the major features of the environment is the 3D representation of concurrent process. 3D representation is used to supply both network-wide interprocess programming capability (capability for 'programming in the large') and real-time programming capability. The authors' idea is to fuse both the block diagram (which is useful to check relationship among large number of processes or processors) and the time chart (which is useful to check precise timing for synchronization) into a single 3D space. The 3D representation gives us a capability for direct and intuitive planning or understanding of complicated relationship among many concurrent processes. To realize the 3D representation, a technology to enable easy handling of virtual 3D object is a definite necessity. Using a stereo display system and a gesture input device (VPL DataGlove), our prototype of the virtual workstation has been implemented. The workstation can supply the 'sensation' of the virtual 3D space to a programmer. Software for the 3D programming environment is implemented on the workstation. According to preliminary assessments, a 50 percent reduction of programming effort is achieved by using the virtual 3D environment. The authors expect that the 3D environment has considerable potential in the field of software engineering.

3D Medical Collaboration Technology to Enhance Emergency Healthcare

PubMed Central

Welch, Greg; Sonnenwald, Diane H; Fuchs, Henry; Cairns, Bruce; Mayer-Patel, Ketan; Söderholm, Hanna M.; Yang, Ruigang; State, Andrei; Towles, Herman; Ilie, Adrian; Ampalam, Manoj; Krishnan, Srinivas; Noel, Vincent; Noland, Michael; Manning, James E.

2009-01-01

Two-dimensional (2D) videoconferencing has been explored widely in the past 15–20 years to support collaboration in healthcare. Two issues that arise in most evaluations of 2D videoconferencing in telemedicine are the difficulty obtaining optimal camera views and poor depth perception. To address these problems, we are exploring the use of a small array of cameras to reconstruct dynamic three-dimensional (3D) views of a remote environment and of events taking place within. The 3D views could be sent across wired or wireless networks to remote healthcare professionals equipped with fixed displays or with mobile devices such as personal digital assistants (PDAs). The remote professionals’ viewpoints could be specified manually or automatically (continuously) via user head or PDA tracking, giving the remote viewers head-slaved or hand-slaved virtual cameras for monoscopic or stereoscopic viewing of the dynamic reconstructions. We call this idea remote 3D medical collaboration. In this article we motivate and explain the vision for 3D medical collaboration technology; we describe the relevant computer vision, computer graphics, display, and networking research; we present a proof-of-concept prototype system; and we present evaluation results supporting the general hypothesis that 3D remote medical collaboration technology could offer benefits over conventional 2D videoconferencing in emergency healthcare. PMID:19521951

3D medical collaboration technology to enhance emergency healthcare.

PubMed

Welch, Gregory F; Sonnenwald, Diane H; Fuchs, Henry; Cairns, Bruce; Mayer-Patel, Ketan; Söderholm, Hanna M; Yang, Ruigang; State, Andrei; Towles, Herman; Ilie, Adrian; Ampalam, Manoj K; Krishnan, Srinivas; Noel, Vincent; Noland, Michael; Manning, James E

2009-04-19

Two-dimensional (2D) videoconferencing has been explored widely in the past 15-20 years to support collaboration in healthcare. Two issues that arise in most evaluations of 2D videoconferencing in telemedicine are the difficulty obtaining optimal camera views and poor depth perception. To address these problems, we are exploring the use of a small array of cameras to reconstruct dynamic three-dimensional (3D) views of a remote environment and of events taking place within. The 3D views could be sent across wired or wireless networks to remote healthcare professionals equipped with fixed displays or with mobile devices such as personal digital assistants (PDAs). The remote professionals' viewpoints could be specified manually or automatically (continuously) via user head or PDA tracking, giving the remote viewers head-slaved or hand-slaved virtual cameras for monoscopic or stereoscopic viewing of the dynamic reconstructions. We call this idea remote 3D medical collaboration. In this article we motivate and explain the vision for 3D medical collaboration technology; we describe the relevant computer vision, computer graphics, display, and networking research; we present a proof-of-concept prototype system; and we present evaluation results supporting the general hypothesis that 3D remote medical collaboration technology could offer benefits over conventional 2D videoconferencing in emergency healthcare.

Grasping trajectories in a virtual environment adhere to Weber's law.

PubMed

Ozana, Aviad; Berman, Sigal; Ganel, Tzvi

2018-06-01

Virtual-reality and telerobotic devices simulate local motor control of virtual objects within computerized environments. Here, we explored grasping kinematics within a virtual environment and tested whether, as in normal 3D grasping, trajectories in the virtual environment are performed analytically, violating Weber's law with respect to object's size. Participants were asked to grasp a series of 2D objects using a haptic system, which projected their movements to a virtual space presented on a computer screen. The apparatus also provided object-specific haptic information upon "touching" the edges of the virtual targets. The results showed that grasping movements performed within the virtual environment did not produce the typical analytical trajectory pattern obtained during 3D grasping. Unlike as in 3D grasping, grasping trajectories in the virtual environment adhered to Weber's law, which indicates relative resolution in size processing. In addition, the trajectory patterns differed from typical trajectories obtained during 3D grasping, with longer times to complete the movement, and with maximum grip apertures appearing relatively early in the movement. The results suggest that grasping movements within a virtual environment could differ from those performed in real space, and are subjected to irrelevant effects of perceptual information. Such atypical pattern of visuomotor control may be mediated by the lack of complete transparency between the interface and the virtual environment in terms of the provided visual and haptic feedback. Possible implications of the findings to movement control within robotic and virtual environments are further discussed.

A standardized set of 3-D objects for virtual reality research and applications.

PubMed

Peeters, David

2018-06-01

The use of immersive virtual reality as a research tool is rapidly increasing in numerous scientific disciplines. By combining ecological validity with strict experimental control, immersive virtual reality provides the potential to develop and test scientific theories in rich environments that closely resemble everyday settings. This article introduces the first standardized database of colored three-dimensional (3-D) objects that can be used in virtual reality and augmented reality research and applications. The 147 objects have been normed for name agreement, image agreement, familiarity, visual complexity, and corresponding lexical characteristics of the modal object names. The availability of standardized 3-D objects for virtual reality research is important, because reaching valid theoretical conclusions hinges critically on the use of well-controlled experimental stimuli. Sharing standardized 3-D objects across different virtual reality labs will allow for science to move forward more quickly.

Discovering new PI3Kα inhibitors with a strategy of combining ligand-based and structure-based virtual screening

NASA Astrophysics Data System (ADS)

Yu, Miao; Gu, Qiong; Xu, Jun

2018-02-01

PI3Kα is a promising drug target for cancer chemotherapy. In this paper, we report a strategy of combing ligand-based and structure-based virtual screening to identify new PI3Kα inhibitors. First, naïve Bayesian (NB) learning models and a 3D-QSAR pharmacophore model were built based upon known PI3Kα inhibitors. Then, the SPECS library was screened by the best NB model. This resulted in virtual hits, which were validated by matching the structures against the pharmacophore models. The pharmacophore matched hits were then docked into PI3Kα crystal structures to form ligand-receptor complexes, which are further validated by the Glide-XP program to result in structural validated hits. The structural validated hits were examined by PI3Kα inhibitory assay. With this screening protocol, ten PI3Kα inhibitors with new scaffolds were discovered with IC50 values ranging 0.44-31.25 μM. The binding affinities for the most active compounds 33 and 74 were estimated through molecular dynamics simulations and MM-PBSA analyses.

A new dynamic 3D virtual methodology for teaching the mechanics of atrial septation as seen in the human heart

PubMed Central

Schleich, Jean-Marc; Dillenseger, Jean-Louis; Houyel, Lucile; Almange, Claude; Anderson, Robert H.

2009-01-01

Background Learning embryology remains difficult, since it requires understanding of many complex phenomena. The temporal evolution of developmental events has classically been illustrated using cartoons, which create difficulty in linking spatial and temporal aspects, such correlation being the keystone of descriptive embryology. Methods We synthesized the bibliographic data from recent studies of atrial septal development. On the basis of this synthesis, consensus on the stages of atrial septation as seen in the human heart has been reached by a group of experts in cardiac embryology and paediatric cardiology. This has permitted the preparation of three-dimensional (3-D) computer graphic objects for the anatomical components involved in the different stages of normal human atrial septation. Results We have provided a virtual guide to the process of normal atrial septation, the animation providing an appreciation of the temporal and morphologic events necessary to separate the systemic and pulmonary venous returns. Conclusion We have shown that our animations of normal human atrial septation increase significantly the teaching of the complex developmental processes involved, and provide a new dynamic for the process of learning. PMID:19363807

Optical 3D surface digitizing in forensic medicine: 3D documentation of skin and bone injuries.

PubMed

Thali, Michael J; Braun, Marcel; Dirnhofer, Richard

2003-11-26

Photography process reduces a three-dimensional (3D) wound to a two-dimensional level. If there is a need for a high-resolution 3D dataset of an object, it needs to be three-dimensionally scanned. No-contact optical 3D digitizing surface scanners can be used as a powerful tool for wound and injury-causing instrument analysis in trauma cases. The 3D skin wound and a bone injury documentation using the optical scanner Advanced TOpometric Sensor (ATOS II, GOM International, Switzerland) will be demonstrated using two illustrative cases. Using this 3D optical digitizing method the wounds (the virtual 3D computer model of the skin and the bone injuries) and the virtual 3D model of the injury-causing tool are graphically documented in 3D in real-life size and shape and can be rotated in the CAD program on the computer screen. In addition, the virtual 3D models of the bone injuries and tool can now be compared in a 3D CAD program against one another in virtual space, to see if there are matching areas. Further steps in forensic medicine will be a full 3D surface documentation of the human body and all the forensic relevant injuries using optical 3D scanners.

Virtual 3D planning of tracheostomy placement and clinical applicability of 3D cannula design: a three-step study.

PubMed

de Kleijn, Bertram J; Kraeima, Joep; Wachters, Jasper E; van der Laan, Bernard F A M; Wedman, Jan; Witjes, M J H; Halmos, Gyorgy B

2018-02-01

We aimed to investigate the potential of 3D virtual planning of tracheostomy tube placement and 3D cannula design to prevent tracheostomy complications due to inadequate cannula position. 3D models of commercially available cannula were positioned in 3D models of the airway. In study (1), a cohort that underwent tracheostomy between 2013 and 2015 was selected (n = 26). The cannula was virtually placed in the airway in the pre-operative CT scan and its position was compared to the cannula position on post-operative CT scans. In study (2), a cohort with neuromuscular disease (n = 14) was analyzed. Virtual cannula placing was performed in CT scans and tested if problems could be anticipated. Finally (3), for a patient with Duchenne muscular dystrophy and complications of conventional tracheostomy cannula, a patient-specific cannula was 3D designed, fabricated, and placed. (1) The 3D planned and post-operative tracheostomy position differed significantly. (2) Three groups of patients were identified: (A) normal anatomy; (B) abnormal anatomy, commercially available cannula fits; and (C) abnormal anatomy, custom-made cannula, may be necessary. (3) The position of the custom-designed cannula was optimal and the trachea healed. Virtual planning of the tracheostomy did not correlate with actual cannula position. Identifying patients with abnormal airway anatomy in whom commercially available cannula cannot be optimally positioned is advantageous. Patient-specific cannula design based on 3D virtualization of the airway was beneficial in a patient with abnormal airway anatomy.

Web 3D for Public, Environmental and Occupational Health: Early Examples from Second Life®

PubMed Central

Kamel Boulos, Maged N.; Ramloll, Rameshsharma; Jones, Ray; Toth-Cohen, Susan

2008-01-01

Over the past three years (2006–2008), the medical/health and public health communities have shown a growing interest in using online 3D virtual worlds like Second Life® (http://secondlife.com/) for health education, community outreach, training and simulations purposes. 3D virtual worlds are seen as the precursors of ‘Web 3D’, the next major iteration of the Internet that will follow in the coming years. This paper provides a tour of several flagship Web 3D experiences in Second Life®, including Play2Train Islands (emergency preparedness training), the US Centers for Disease Control and Prevention—CDC Island (public health), Karuna Island (AIDS support and information), Tox Town at Virtual NLM Island (US National Library of Medicine - environmental health), and Jefferson’s Occupational Therapy Center. We also discuss the potential and future of Web 3D. These are still early days of 3D virtual worlds, and there are still many more untapped potentials and affordances of 3D virtual worlds that are yet to be explored, as the technology matures further and improves over the coming months and years. PMID:19190358

Web3D Technologies in Learning, Education and Training: Motivations, Issues, Opportunities

ERIC Educational Resources Information Center

Chittaro, Luca; Ranon, Roberto

2007-01-01

Web3D open standards allow the delivery of interactive 3D virtual learning environments through the Internet, reaching potentially large numbers of learners worldwide, at any time. This paper introduces the educational use of virtual reality based on Web3D technologies. After briefly presenting the main Web3D technologies, we summarize the…

D Visualization for Virtual Museum Development

NASA Astrophysics Data System (ADS)

Skamantzari, M.; Georgopoulos, A.

2016-06-01

The interest in the development of virtual museums is nowadays rising rapidly. During the last decades there have been numerous efforts concerning the 3D digitization of cultural heritage and the development of virtual museums, digital libraries and serious games. The realistic result has always been the main concern and a real challenge when it comes to 3D modelling of monuments, artifacts and especially sculptures. This paper implements, investigates and evaluates the results of the photogrammetric methods and 3D surveys that were used for the development of a virtual museum. Moreover, the decisions, the actions, the methodology and the main elements that this kind of application should include and take into consideration are described and analysed. It is believed that the outcomes of this application will be useful to researchers who are planning to develop and further improve the attempts made on virtual museums and mass production of 3D models.

Objective and subjective quality assessment of geometry compression of reconstructed 3D humans in a 3D virtual room

NASA Astrophysics Data System (ADS)

Mekuria, Rufael; Cesar, Pablo; Doumanis, Ioannis; Frisiello, Antonella

2015-09-01

Compression of 3D object based video is relevant for 3D Immersive applications. Nevertheless, the perceptual aspects of the degradation introduced by codecs for meshes and point clouds are not well understood. In this paper we evaluate the subjective and objective degradations introduced by such codecs in a state of art 3D immersive virtual room. In the 3D immersive virtual room, users are captured with multiple cameras, and their surfaces are reconstructed as photorealistic colored/textured 3D meshes or point clouds. To test the perceptual effect of compression and transmission, we render degraded versions with different frame rates in different contexts (near/far) in the scene. A quantitative subjective study with 16 users shows that negligible distortion of decoded surfaces compared to the original reconstructions can be achieved in the 3D virtual room. In addition, a qualitative task based analysis in a full prototype field trial shows increased presence, emotion, user and state recognition of the reconstructed 3D Human representation compared to animated computer avatars.

AGGRESCAN3D (A3D): server for prediction of aggregation properties of protein structures.

PubMed

Zambrano, Rafael; Jamroz, Michal; Szczasiuk, Agata; Pujols, Jordi; Kmiecik, Sebastian; Ventura, Salvador

2015-07-01

Protein aggregation underlies an increasing number of disorders and constitutes a major bottleneck in the development of therapeutic proteins. Our present understanding on the molecular determinants of protein aggregation has crystalized in a series of predictive algorithms to identify aggregation-prone sites. A majority of these methods rely only on sequence. Therefore, they find difficulties to predict the aggregation properties of folded globular proteins, where aggregation-prone sites are often not contiguous in sequence or buried inside the native structure. The AGGRESCAN3D (A3D) server overcomes these limitations by taking into account the protein structure and the experimental aggregation propensity scale from the well-established AGGRESCAN method. Using the A3D server, the identified aggregation-prone residues can be virtually mutated to design variants with increased solubility, or to test the impact of pathogenic mutations. Additionally, A3D server enables to take into account the dynamic fluctuations of protein structure in solution, which may influence aggregation propensity. This is possible in A3D Dynamic Mode that exploits the CABS-flex approach for the fast simulations of flexibility of globular proteins. The A3D server can be accessed at http://biocomp.chem.uw.edu.pl/A3D/. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

Decision PBL: A 4-year retrospective case study of the use of virtual patients in problem-based learning.

PubMed

Ellaway, Rachel H; Poulton, Terry; Jivram, Trupti

2015-01-01

In 2009, St George's University of London (SGUL) replaced their paper-based problem-based learning (PBL) cases with virtual patients for intermediate-level undergraduate students. This involved the development of Decision-Problem-Based Learning (D-PBL), a variation on progressive-release PBL that uses virtual patients instead of paper cases, and focuses on patient management decisions and their consequences. Using a case study method, this paper describes four years of developing and running D-PBL at SGUL from individual activities up to the ways in which D-PBL functioned as an educational system. A number of broad issues were identified: the importance of debates and decision-making in making D-PBL activities engaging and rewarding; the complexities of managing small group dynamics; the time taken to complete D-PBL activities; the changing role of the facilitator; and the erosion of the D-PBL process over time. A key point in understanding this work is the construction and execution of the D-PBL activity, as much of the value of this approach arises from the actions and interactions of students, their facilitators and the virtual patients rather than from the design of the virtual patients alone. At a systems level D-PBL needs to be periodically refreshed to retain its effectiveness.

A comparative analysis of dynamic grids vs. virtual grids using the A3pviGrid framework.

PubMed

Shankaranarayanan, Avinas; Amaldas, Christine

2010-11-01

With the proliferation of Quad/Multi-core micro-processors in mainstream platforms such as desktops and workstations; a large number of unused CPU cycles can be utilized for running virtual machines (VMs) as dynamic nodes in distributed environments. Grid services and its service oriented business broker now termed cloud computing could deploy image based virtualization platforms enabling agent based resource management and dynamic fault management. In this paper we present an efficient way of utilizing heterogeneous virtual machines on idle desktops as an environment for consumption of high performance grid services. Spurious and exponential increases in the size of the datasets are constant concerns in medical and pharmaceutical industries due to the constant discovery and publication of large sequence databases. Traditional algorithms are not modeled at handing large data sizes under sudden and dynamic changes in the execution environment as previously discussed. This research was undertaken to compare our previous results with running the same test dataset with that of a virtual Grid platform using virtual machines (Virtualization). The implemented architecture, A3pviGrid utilizes game theoretic optimization and agent based team formation (Coalition) algorithms to improve upon scalability with respect to team formation. Due to the dynamic nature of distributed systems (as discussed in our previous work) all interactions were made local within a team transparently. This paper is a proof of concept of an experimental mini-Grid test-bed compared to running the platform on local virtual machines on a local test cluster. This was done to give every agent its own execution platform enabling anonymity and better control of the dynamic environmental parameters. We also analyze performance and scalability of Blast in a multiple virtual node setup and present our findings. This paper is an extension of our previous research on improving the BLAST application framework using dynamic Grids on virtualization platforms such as the virtual box.

Issues and Challenges of Teaching and Learning in 3D Virtual Worlds: Real Life Case Studies

ERIC Educational Resources Information Center

Pfeil, Ulrike; Ang, Chee Siang; Zaphiris, Panayiotis

2009-01-01

We aimed to study the characteristics and usage patterns of 3D virtual worlds in the context of teaching and learning. To achieve this, we organised a full-day workshop to explore, discuss and investigate the educational use of 3D virtual worlds. Thirty participants took part in the workshop. All conversations were recorded and transcribed for…

The Learner Characteristics, Features of Desktop 3D Virtual Reality Environments, and College Chemistry Instruction: A Structural Equation Modeling Analysis

ERIC Educational Resources Information Center

Merchant, Zahira; Goetz, Ernest T.; Keeney-Kennicutt, Wendy; Kwok, Oi-man; Cifuentes, Lauren; Davis, Trina J.

2012-01-01

We examined a model of the impact of a 3D desktop virtual reality environment on the learner characteristics (i.e. perceptual and psychological variables) that can enhance chemistry-related learning achievements in an introductory college chemistry class. The relationships between the 3D virtual reality features and the chemistry learning test as…

3D Elevation Program—Virtual USA in 3D

USGS Publications Warehouse

Lukas, Vicki; Stoker, J.M.

2016-04-14

The U.S. Geological Survey (USGS) 3D Elevation Program (3DEP) uses a laser system called ‘lidar’ (light detection and ranging) to create a virtual reality map of the Nation that is very accurate. 3D maps have many uses with new uses being discovered all the time.  

Integration of virtual and real scenes within an integral 3D imaging environment

NASA Astrophysics Data System (ADS)

Ren, Jinsong; Aggoun, Amar; McCormick, Malcolm

2002-11-01

The Imaging Technologies group at De Montfort University has developed an integral 3D imaging system, which is seen as the most likely vehicle for 3D television avoiding psychological effects. To create real fascinating three-dimensional television programs, a virtual studio that performs the task of generating, editing and integrating the 3D contents involving virtual and real scenes is required. The paper presents, for the first time, the procedures, factors and methods of integrating computer-generated virtual scenes with real objects captured using the 3D integral imaging camera system. The method of computer generation of 3D integral images, where the lens array is modelled instead of the physical camera is described. In the model each micro-lens that captures different elemental images of the virtual scene is treated as an extended pinhole camera. An integration process named integrated rendering is illustrated. Detailed discussion and deep investigation are focused on depth extraction from captured integral 3D images. The depth calculation method from the disparity and the multiple baseline method that is used to improve the precision of depth estimation are also presented. The concept of colour SSD and its further improvement in the precision is proposed and verified.

A Virtual Campus Based on Human Factor Engineering

ERIC Educational Resources Information Center

Yang, Yuting; Kang, Houliang

2014-01-01

Three Dimensional or 3D virtual reality has become increasingly popular in many areas, especially in building a digital campus. This paper introduces a virtual campus, which is based on a 3D model of The Tourism and Culture College of Yunnan University (TCYU). Production of the virtual campus was aided by Human Factor and Ergonomics (HF&E), an…

The Efficacy of an Immersive 3D Virtual versus 2D Web Environment in Intercultural Sensitivity Acquisition

ERIC Educational Resources Information Center

Coffey, Amy Jo; Kamhawi, Rasha; Fishwick, Paul; Henderson, Julie

2017-01-01

Relatively few studies have empirically tested computer-based immersive virtual environments' efficacy in teaching or enhancing pro-social attitudes, such as intercultural sensitivity. This channel study experiment was conducted (N = 159) to compare what effects, if any, an immersive 3D virtual environment would have upon subjects' intercultural…

Attitude and Self-Efficacy Change: English Language Learning in Virtual Worlds

ERIC Educational Resources Information Center

Zheng, Dongping; Young, Michael F.; Brewer, Robert A.; Wagner, Manuela

2009-01-01

This study explored affective factors in learning English as a foreign language in a 3D game-like virtual world, Quest Atlantis (QA). Through the use of communication tools (e.g., chat, bulletin board, telegrams, and email), 3D avatars, and 2D webpage navigation tools in virtual space, nonnative English speakers (NNES) co-solved online…

Rational approach to identify newer caspase-1 inhibitors using pharmacophore based virtual screening, docking and molecular dynamic simulation studies.

PubMed

Patel, Shivani; Modi, Palmi; Chhabria, Mahesh

2018-05-01

Caspase-1 is a key endoprotease responsible for the post-translational processing of pro-inflammatory cytokines IL-1β, 18 & 33. Excessive secretion of IL-1β leads to numerous inflammatory and autoimmune diseases. Thus caspase-1 inhibition would be considered as an important therapeutic strategy for development of newer anti-inflammatory agents. Here we have employed an integrated virtual screening by combining pharmacophore mapping and docking to identify small molecules as caspase-1 inhibitors. The ligand based 3D pharmacophore model was generated having the essential structural features of (HBA, HY & RA) using a data set of 27 compounds. A validated pharmacophore hypothesis (Hypo 1) was used to screen ZINC and Minimaybridge chemical databases. The retrieved virtual hits were filtered by ADMET properties and molecular docking analysis. Subsequently, the cross-docking study was also carried out using crystal structure of caspase-1, 3, 7 and 8 to identify the key residual interaction for specific caspase-1 inhibition. Finally, the best mapped and top scored (ZINC00885612, ZINC72003647, BTB04175 and BTB04410) molecules were subjected to molecular dynamics simulation for accessing the dynamic structure of protein after ligand binding. This study identifies the most promising hits, which can be leads for the development of novel caspase-1 inhibitors as anti-inflammatory agents. Copyright © 2018 Elsevier Inc. All rights reserved.

SU-F-BRD-11: A Virtual Simulator Designed for Collision Prevention in Proton Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jung, H; Kum, O; Park, H

2015-06-15

Purpose: In proton therapy, collisions between patient and nozzle potentially occur in attaining minimal air gap due to the large nozzle structure. Thus, we developed software predicting the collisions of the nozzle and patient by simulating treatments. Methods: 3D modeling of a gantry inner-floor, nozzle and robotic-couch was done by using the SolidWorks based on the manufacturer’s machine data. To obtain patient body information, a 3D-scanner was utilized to scan a patient right before CT scanning. From the acquired images, a 3D-image of the patient’s body contour was reconstructed. The accuracy of the image was confirmed against the CT imagemore » for a humanoid phantom. The machine components and the virtual patient were combined on the treatment-room coordinate system, resulting in a virtual simulator. The simulator simulated the motion of its components such as rotation and translation of gantry, nozzle and couch, in real scale. Collision, if any, was examined both in static mode and dynamic mode. The static mode checks only at fixed positions of the machine’s components while dynamic mode examines while one component is in motion. Collision was notified if any voxel of two components, for example a nozzle and a patient or couch, overlapped when calculating volume locations. The event and collision point are visualized and colliding volumes are reported. Results: All components were successfully assembled and the motions could be accurately controlled. The 3D-shape of a phantom agreed with CT images within a deviation of 2 mm. Collision situations can be simulated within minutes and the results are displayed and reported. Conclusion: The developed software will be useful in improving patient safety and clinical efficiency for proton therapy. This work was supported by the National Research Foundation of Korea funded by Ministry of Science, ICT & Future Planning (2012M3A9B6055201, 2013M2A2A7043507), and Samsung Medical Center grant (GFO1130081)« less

Agreement and reliability of pelvic floor measurements during contraction using three-dimensional pelvic floor ultrasound and virtual reality.

PubMed

Speksnijder, L; Rousian, M; Steegers, E A P; Van Der Spek, P J; Koning, A H J; Steensma, A B

2012-07-01

Virtual reality is a novel method of visualizing ultrasound data with the perception of depth and offers possibilities for measuring non-planar structures. The levator ani hiatus has both convex and concave aspects. The aim of this study was to compare levator ani hiatus volume measurements obtained with conventional three-dimensional (3D) ultrasound and with a virtual reality measurement technique and to establish their reliability and agreement. 100 symptomatic patients visiting a tertiary pelvic floor clinic with a normal intact levator ani muscle diagnosed on translabial ultrasound were selected. Datasets were analyzed using a rendered volume with a slice thickness of 1.5 cm at the level of minimal hiatal dimensions during contraction. The levator area (in cm(2)) was measured and multiplied by 1.5 to get the levator ani hiatus volume in conventional 3D ultrasound (in cm(3)). Levator ani hiatus volume measurements were then measured semi-automatically in virtual reality (cm(3) ) using a segmentation algorithm. An intra- and interobserver analysis of reliability and agreement was performed in 20 randomly chosen patients. The mean difference between levator ani hiatus volume measurements performed using conventional 3D ultrasound and virtual reality was 0.10 (95% CI, - 0.15 to 0.35) cm(3). The intraclass correlation coefficient (ICC) comparing conventional 3D ultrasound with virtual reality measurements was > 0.96. Intra- and interobserver ICCs for conventional 3D ultrasound measurements were > 0.94 and for virtual reality measurements were > 0.97, indicating good reliability for both. Levator ani hiatus volume measurements performed using virtual reality were reliable and the results were similar to those obtained with conventional 3D ultrasonography. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.

Combined virtual and real robotic test-bed for single operator control of multiple robots

NASA Astrophysics Data System (ADS)

Lee, Sam Y.-S.; Hunt, Shawn; Cao, Alex; Pandya, Abhilash

2010-04-01

Teams of heterogeneous robots with different dynamics or capabilities could perform a variety of tasks such as multipoint surveillance, cooperative transport and explorations in hazardous environments. In this study, we work with heterogeneous robots of semi-autonomous ground and aerial robots for contaminant localization. We developed a human interface system which linked every real robot to its virtual counterpart. A novel virtual interface has been integrated with Augmented Reality that can monitor the position and sensory information from video feed of ground and aerial robots in the 3D virtual environment, and improve user situational awareness. An operator can efficiently control the real multi-robots using the Drag-to-Move method on the virtual multi-robots. This enables an operator to control groups of heterogeneous robots in a collaborative way for allowing more contaminant sources to be pursued simultaneously. The advanced feature of the virtual interface system is guarded teleoperation. This can be used to prevent operators from accidently driving multiple robots into walls and other objects. Moreover, the feature of the image guidance and tracking is able to reduce operator workload.

SimPackJ/S: a web-oriented toolkit for discrete event simulation

NASA Astrophysics Data System (ADS)

Park, Minho; Fishwick, Paul A.

2002-07-01

SimPackJ/S is the JavaScript and Java version of SimPack, which means SimPackJ/S is a collection of JavaScript and Java libraries and executable programs for computer simulations. The main purpose of creating SimPackJ/S is that we allow existing SimPack users to expand simulation areas and provide future users with a freeware simulation toolkit to simulate and model a system in web environments. One of the goals for this paper is to introduce SimPackJ/S. The other goal is to propose translation rules for converting C to JavaScript and Java. Most parts demonstrate the translation rules with examples. In addition, we discuss a 3D dynamic system model and overview an approach to 3D dynamic systems using SimPackJ/S. We explain an interface between SimPackJ/S and the 3D language--Virtual Reality Modeling Language (VRML). This paper documents how to translate C to JavaScript and Java and how to utilize SimPackJ/S within a 3D web environment.

The Virtual Mouse Brain: A Computational Neuroinformatics Platform to Study Whole Mouse Brain Dynamics.

PubMed

Melozzi, Francesca; Woodman, Marmaduke M; Jirsa, Viktor K; Bernard, Christophe

2017-01-01

Connectome-based modeling of large-scale brain network dynamics enables causal in silico interrogation of the brain's structure-function relationship, necessitating the close integration of diverse neuroinformatics fields. Here we extend the open-source simulation software The Virtual Brain (TVB) to whole mouse brain network modeling based on individual diffusion magnetic resonance imaging (dMRI)-based or tracer-based detailed mouse connectomes. We provide practical examples on how to use The Virtual Mouse Brain (TVMB) to simulate brain activity, such as seizure propagation and the switching behavior of the resting state dynamics in health and disease. TVMB enables theoretically driven experimental planning and ways to test predictions in the numerous strains of mice available to study brain function in normal and pathological conditions.

Demonstration of three gorges archaeological relics based on 3D-visualization technology

NASA Astrophysics Data System (ADS)

Xu, Wenli

2015-12-01

This paper mainly focuses on the digital demonstration of three gorges archeological relics to exhibit the achievements of the protective measures. A novel and effective method based on 3D-visualization technology, which includes large-scaled landscape reconstruction, virtual studio, and virtual panoramic roaming, etc, is proposed to create a digitized interactive demonstration system. The method contains three stages: pre-processing, 3D modeling and integration. Firstly, abundant archaeological information is classified according to its history and geographical information. Secondly, build up a 3D-model library with the technology of digital images processing and 3D modeling. Thirdly, use virtual reality technology to display the archaeological scenes and cultural relics vividly and realistically. The present work promotes the application of virtual reality to digital projects and enriches the content of digital archaeology.

Education System Using Interactive 3D Computer Graphics (3D-CG) Animation and Scenario Language for Teaching Materials

ERIC Educational Resources Information Center

Matsuda, Hiroshi; Shindo, Yoshiaki

2006-01-01

The 3D computer graphics (3D-CG) animation using a virtual actor's speaking is very effective as an educational medium. But it takes a long time to produce a 3D-CG animation. To reduce the cost of producing 3D-CG educational contents and improve the capability of the education system, we have developed a new education system using Virtual Actor.…

Characterisation of dynamic couplings at lower limb residuum/socket interface using 3D motion capture.

PubMed

Tang, Jinghua; McGrath, Michael; Laszczak, Piotr; Jiang, Liudi; Bader, Dan L; Moser, David; Zahedi, Saeed

2015-12-01

Design and fitting of artificial limbs to lower limb amputees are largely based on the subjective judgement of the prosthetist. Understanding the science of three-dimensional (3D) dynamic coupling at the residuum/socket interface could potentially aid the design and fitting of the socket. A new method has been developed to characterise the 3D dynamic coupling at the residuum/socket interface using 3D motion capture based on a single case study of a trans-femoral amputee. The new model incorporated a Virtual Residuum Segment (VRS) and a Socket Segment (SS) which combined to form the residuum/socket interface. Angular and axial couplings between the two segments were subsequently determined. Results indicated a non-rigid angular coupling in excess of 10° in the quasi-sagittal plane and an axial coupling of between 21 and 35 mm. The corresponding angular couplings of less than 4° and 2° were estimated in the quasi-coronal and quasi-transverse plane, respectively. We propose that the combined experimental and analytical approach adopted in this case study could aid the iterative socket fitting process and could potentially lead to a new socket design. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

Dynamic 3D echocardiography in virtual reality

PubMed Central

van den Bosch, Annemien E; Koning, Anton HJ; Meijboom, Folkert J; McGhie, Jackie S; Simoons, Maarten L; van der Spek, Peter J; Bogers, Ad JJC

2005-01-01

Background This pilot study was performed to evaluate whether virtual reality is applicable for three-dimensional echocardiography and if three-dimensional echocardiographic 'holograms' have the potential to become a clinically useful tool. Methods Three-dimensional echocardiographic data sets from 2 normal subjects and from 4 patients with a mitral valve pathological condition were included in the study. The three-dimensional data sets were acquired with the Philips Sonos 7500 echo-system and transferred to the BARCO (Barco N.V., Kortrijk, Belgium) I-space. Ten independent observers assessed the 6 three-dimensional data sets with and without mitral valve pathology. After 10 minutes' instruction in the I-Space, all of the observers could use the virtual pointer that is necessary to create cut planes in the hologram. Results The 10 independent observers correctly assessed the normal and pathological mitral valve in the holograms (analysis time approximately 10 minutes). Conclusion this report shows that dynamic holographic imaging of three-dimensional echocardiographic data is feasible. However, the applicability and use-fullness of this technology in clinical practice is still limited. PMID:16375768

Not Just a Game … When We Play Together, We Learn Together: Interactive Virtual Environments and Gaming Engines for Geospatial Visualization

NASA Astrophysics Data System (ADS)

Shipman, J. S.; Anderson, J. W.

2017-12-01

An ideal tool for ecologists and land managers to investigate the impacts of both projected environmental changes and policy alternatives is the creation of immersive, interactive, virtual landscapes. As a new frontier in visualizing and understanding geospatial data, virtual landscapes require a new toolbox for data visualization that includes traditional GIS tools and uncommon tools such as the Unity3d game engine. Game engines provide capabilities to not only explore data but to build and interact with dynamic models collaboratively. These virtual worlds can be used to display and illustrate data that is often more understandable and plausible to both stakeholders and policy makers than is achieved using traditional maps.Within this context we will present funded research that has been developed utilizing virtual landscapes for geographic visualization and decision support among varied stakeholders. We will highlight the challenges and lessons learned when developing interactive virtual environments that require large multidisciplinary team efforts with varied competences. The results will emphasize the importance of visualization and interactive virtual environments and the link with emerging research disciplines within Visual Analytics.

Effects of Presence, Copresence, and Flow on Learning Outcomes in 3D Learning Spaces

ERIC Educational Resources Information Center

Hassell, Martin D.; Goyal, Sandeep; Limayem, Moez; Boughzala, Imed

2012-01-01

The level of satisfaction and effectiveness of 3D virtual learning environments were examined. Additionally, 3D virtual learning environments were compared with face-to-face learning environments. Students that experienced higher levels of flow and presence also experienced more satisfaction but not necessarily more effectiveness with 3D virtual…

Understanding Human Perception of Building Categories in Virtual 3d Cities - a User Study

NASA Astrophysics Data System (ADS)

Tutzauer, P.; Becker, S.; Niese, T.; Deussen, O.; Fritsch, D.

2016-06-01

Virtual 3D cities are becoming increasingly important as a means of visually communicating diverse urban-related information. To get a deeper understanding of a human's cognitive experience of virtual 3D cities, this paper presents a user study on the human ability to perceive building categories (e.g. residential home, office building, building with shops etc.) from geometric 3D building representations. The study reveals various dependencies between geometric properties of the 3D representations and the perceptibility of the building categories. Knowledge about which geometries are relevant, helpful or obstructive for perceiving a specific building category is derived. The importance and usability of such knowledge is demonstrated based on a perception-guided 3D building abstraction process.

[Development of a software for 3D virtual phantom design].

PubMed

Zou, Lian; Xie, Zhao; Wu, Qi

2014-02-01

In this paper, we present a 3D virtual phantom design software, which was developed based on object-oriented programming methodology and dedicated to medical physics research. This software was named Magical Phan tom (MPhantom), which is composed of 3D visual builder module and virtual CT scanner. The users can conveniently construct any complex 3D phantom, and then export the phantom as DICOM 3.0 CT images. MPhantom is a user-friendly and powerful software for 3D phantom configuration, and has passed the real scene's application test. MPhantom will accelerate the Monte Carlo simulation for dose calculation in radiation therapy and X ray imaging reconstruction algorithm research.

Realistic terrain visualization based on 3D virtual world technology

NASA Astrophysics Data System (ADS)

Huang, Fengru; Lin, Hui; Chen, Bin; Xiao, Cai

2009-09-01

The rapid advances in information technologies, e.g., network, graphics processing, and virtual world, have provided challenges and opportunities for new capabilities in information systems, Internet applications, and virtual geographic environments, especially geographic visualization and collaboration. In order to achieve meaningful geographic capabilities, we need to explore and understand how these technologies can be used to construct virtual geographic environments to help to engage geographic research. The generation of three-dimensional (3D) terrain plays an important part in geographical visualization, computer simulation, and virtual geographic environment applications. The paper introduces concepts and technologies of virtual worlds and virtual geographic environments, explores integration of realistic terrain and other geographic objects and phenomena of natural geographic environment based on SL/OpenSim virtual world technologies. Realistic 3D terrain visualization is a foundation of construction of a mirror world or a sand box model of the earth landscape and geographic environment. The capabilities of interaction and collaboration on geographic information are discussed as well. Further virtual geographic applications can be developed based on the foundation work of realistic terrain visualization in virtual environments.

Realistic terrain visualization based on 3D virtual world technology

NASA Astrophysics Data System (ADS)

Huang, Fengru; Lin, Hui; Chen, Bin; Xiao, Cai

2010-11-01

The rapid advances in information technologies, e.g., network, graphics processing, and virtual world, have provided challenges and opportunities for new capabilities in information systems, Internet applications, and virtual geographic environments, especially geographic visualization and collaboration. In order to achieve meaningful geographic capabilities, we need to explore and understand how these technologies can be used to construct virtual geographic environments to help to engage geographic research. The generation of three-dimensional (3D) terrain plays an important part in geographical visualization, computer simulation, and virtual geographic environment applications. The paper introduces concepts and technologies of virtual worlds and virtual geographic environments, explores integration of realistic terrain and other geographic objects and phenomena of natural geographic environment based on SL/OpenSim virtual world technologies. Realistic 3D terrain visualization is a foundation of construction of a mirror world or a sand box model of the earth landscape and geographic environment. The capabilities of interaction and collaboration on geographic information are discussed as well. Further virtual geographic applications can be developed based on the foundation work of realistic terrain visualization in virtual environments.

Projecting 2D gene expression data into 3D and 4D space.

PubMed

Gerth, Victor E; Katsuyama, Kaori; Snyder, Kevin A; Bowes, Jeff B; Kitayama, Atsushi; Ueno, Naoto; Vize, Peter D

2007-04-01

Video games typically generate virtual 3D objects by texture mapping an image onto a 3D polygonal frame. The feeling of movement is then achieved by mathematically simulating camera movement relative to the polygonal frame. We have built customized scripts that adapt video game authoring software to texture mapping images of gene expression data onto b-spline based embryo models. This approach, known as UV mapping, associates two-dimensional (U and V) coordinates within images to the three dimensions (X, Y, and Z) of a b-spline model. B-spline model frameworks were built either from confocal data or de novo extracted from 2D images, once again using video game authoring approaches. This system was then used to build 3D models of 182 genes expressed in developing Xenopus embryos and to implement these in a web-accessible database. Models can be viewed via simple Internet browsers and utilize openGL hardware acceleration via a Shockwave plugin. Not only does this database display static data in a dynamic and scalable manner, the UV mapping system also serves as a method to align different images to a common framework, an approach that may make high-throughput automated comparisons of gene expression patterns possible. Finally, video game systems also have elegant methods for handling movement, allowing biomechanical algorithms to drive the animation of models. With further development, these biomechanical techniques offer practical methods for generating virtual embryos that recapitulate morphogenesis.

Brave New (Interactive) Worlds: A Review of the Design Affordances and Constraints of Two 3D Virtual Worlds as Interactive Learning Environments

ERIC Educational Resources Information Center

Dickey, Michele D.

2005-01-01

Three-dimensional virtual worlds are an emerging medium currently being used in both traditional classrooms and for distance education. Three-dimensional (3D) virtual worlds are a combination of desk-top interactive Virtual Reality within a chat environment. This analysis provides an overview of Active Worlds Educational Universe and Adobe…

Virtual rough samples to test 3D nanometer-scale scanning electron microscopy stereo photogrammetry.

PubMed

Villarrubia, J S; Tondare, V N; Vladár, A E

2016-01-01

The combination of scanning electron microscopy for high spatial resolution, images from multiple angles to provide 3D information, and commercially available stereo photogrammetry software for 3D reconstruction offers promise for nanometer-scale dimensional metrology in 3D. A method is described to test 3D photogrammetry software by the use of virtual samples-mathematical samples from which simulated images are made for use as inputs to the software under test. The virtual sample is constructed by wrapping a rough skin with any desired power spectral density around a smooth near-trapezoidal line with rounded top corners. Reconstruction is performed with images simulated from different angular viewpoints. The software's reconstructed 3D model is then compared to the known geometry of the virtual sample. Three commercial photogrammetry software packages were tested. Two of them produced results for line height and width that were within close to 1 nm of the correct values. All of the packages exhibited some difficulty in reconstructing details of the surface roughness.

Integrating a facial scan, virtual smile design, and 3D virtual patient for treatment with CAD-CAM ceramic veneers: A clinical report.

PubMed

Lin, Wei-Shao; Harris, Bryan T; Phasuk, Kamolphob; Llop, Daniel R; Morton, Dean

2018-02-01

This clinical report describes a digital workflow using the virtual smile design approach augmented with a static 3-dimensional (3D) virtual patient with photorealistic appearance to restore maxillary central incisors by using computer-aided design and computer-aided manufacturing (CAD-CAM) monolithic lithium disilicate ceramic veneers. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Electrophysiological Rotor Ablation in In-Silico Modeling of Atrial Fibrillation: Comparisons with Dominant Frequency, Shannon Entropy, and Phase Singularity.

PubMed

Hwang, Minki; Song, Jun-Seop; Lee, Young-Seon; Li, Changyong; Shim, Eun Bo; Pak, Hui-Nam

2016-01-01

Although rotors have been considered among the drivers of atrial fibrillation (AF), the rotor definition is inconsistent. We evaluated the nature of rotors in 2D and 3D in- silico models of persistent AF (PeAF) by analyzing phase singularity (PS), dominant frequency (DF), Shannon entropy (ShEn), and complex fractionated atrial electrogram cycle length (CFAE-CL) and their ablation. Mother rotor was spatiotemporally defined as stationary reentries with a meandering tip remaining within half the wavelength and lasting longer than 5 s. We generated 2D- and 3D-maps of the PS, DF, ShEn, and CFAE-CL during AF. The spatial correlations and ablation outcomes targeting each parameter were analyzed. 1. In the 2D PeAF model, we observed a mother rotor that matched relatively well with DF (>9 Hz, 71.0%, p<0.001), ShEn (upper 2.5%, 33.2%, p<0.001), and CFAE-CL (lower 2.5%, 23.7%, p<0.001). 2. The 3D-PeAF model also showed mother rotors that had spatial correlations with DF (>5.5 Hz, 39.7%, p<0.001), ShEn (upper 8.5%, 15.1%, p <0.001), and CFAE (lower 8.5%, 8.0%, p = 0.002). 3. In both the 2D and 3D models, virtual ablation targeting the upper 5% of the DF terminated AF within 20 s, but not the ablations based on long-lasting PS, high ShEn area, or lower CFAE-CL area. Mother rotors were observed in both 2D and 3D human AF models. Rotor locations were well represented by DF, and their virtual ablation altered wave dynamics and terminated AF.

Electrophysiological Rotor Ablation in In-Silico Modeling of Atrial Fibrillation: Comparisons with Dominant Frequency, Shannon Entropy, and Phase Singularity

PubMed Central

Hwang, Minki; Song, Jun-Seop; Lee, Young-Seon; Li, Changyong; Shim, Eun Bo; Pak, Hui-Nam

2016-01-01

Background Although rotors have been considered among the drivers of atrial fibrillation (AF), the rotor definition is inconsistent. We evaluated the nature of rotors in 2D and 3D in- silico models of persistent AF (PeAF) by analyzing phase singularity (PS), dominant frequency (DF), Shannon entropy (ShEn), and complex fractionated atrial electrogram cycle length (CFAE-CL) and their ablation. Methods Mother rotor was spatiotemporally defined as stationary reentries with a meandering tip remaining within half the wavelength and lasting longer than 5 s. We generated 2D- and 3D-maps of the PS, DF, ShEn, and CFAE-CL during AF. The spatial correlations and ablation outcomes targeting each parameter were analyzed. Results 1. In the 2D PeAF model, we observed a mother rotor that matched relatively well with DF (>9 Hz, 71.0%, p<0.001), ShEn (upper 2.5%, 33.2%, p<0.001), and CFAE-CL (lower 2.5%, 23.7%, p<0.001). 2. The 3D-PeAF model also showed mother rotors that had spatial correlations with DF (>5.5 Hz, 39.7%, p<0.001), ShEn (upper 8.5%, 15.1%, p <0.001), and CFAE (lower 8.5%, 8.0%, p = 0.002). 3. In both the 2D and 3D models, virtual ablation targeting the upper 5% of the DF terminated AF within 20 s, but not the ablations based on long-lasting PS, high ShEn area, or lower CFAE-CL area. Conclusion Mother rotors were observed in both 2D and 3D human AF models. Rotor locations were well represented by DF, and their virtual ablation altered wave dynamics and terminated AF. PMID:26909492

Helical CT scan with 2D and 3D reconstructions and virtual endoscopy versus conventional endoscopy in the assessment of airway disease in neonates, infants and children.

PubMed

Yunus, Mahira

2012-11-01

To study the use of helical computed tomography 2-D and 3-D images, and virtual endoscopy in the evaluation of airway disease in neonates, infants and children and its value in lesion detection, characterisation and extension. Conducted at Al-Noor Hospital, Makkah, Saudi Arabia, from January 1 to June 30, 2006, the study comprised of 40 patients with strider, having various causes of airway obstruction. They were examined by helical CT scan with 2-D and 3-D reconstructions and virtual endoscopy. The level and characterisation of lesions were carried out and results were compared with actual endoscopic findings. Conventional endoscopy was chosen as the gold standard, and the evaluation of endoscopy was done in terms of sensitivity and specificity of the procedure. For statistical purposes, SPSS version 10 was used. All CT methods detected airway stenosis or obstruction. Accuracy was 98% (n=40) for virtual endoscopy, 96% (n=48) for 3-D external rendering, 90% (n=45) for multiplanar reconstructions and 86% (n=43) for axial images. Comparing the results of 3-D internal and external volume rendering images with conventional endoscopy for detection and grading of stenosis were closer than with 2-D minimum intensity multiplanar reconstruction and axial CT slices. Even high-grade stenosis could be evaluated with virtual endoscope through which conventional endoscope cannot be passed. A case of 4-year-old patient with tracheomalacia could not be diagnosed by helical CT scan and virtual bronchoscopy which was diagriosed on conventional endoscopy and needed CT scan in inspiration and expiration. Virtual endoscopy [VE] enabled better assessment of stenosis compared to the reading of 3-D external rendering, 2-D multiplanar reconstruction [MPR] or axial slices. It can replace conventional endoscopy in the assessment of airway disease without any additional risk.

Virtually fabricated guide for placement of the C-tube miniplate.

PubMed

Paek, Janghyun; Jeong, Do-Min; Kim, Yong; Kim, Seong-Hun; Chung, Kyu-Rhim; Nelson, Gerald

2014-05-01

This paper introduces a virtually planned and stereolithographically fabricated guiding system that will allow the clinician to plan carefully for the best location of the device and to achieve an accurate position without complications. The scanned data from preoperative dental casts were edited to obtain preoperative 3-dimensional (3D) virtual models of the dentition. After the 3D virtual models were repositioned, the 3D virtual surgical guide was fabricated. A surgical guide was created onscreen, and then these virtual guides were materialized into real ones using the stereolithographic technique. Whereas the previously described guide required laboratory work to be performed by the orthodontist, our technique is more convenient because the laboratory work is done remotely by computer-aided design/computer-aided manufacturing technology. Because the miniplate is firmly held in place as the patient holds his or her mandibular teeth against the occlusal pad of the surgical guide, there is no risk that the miniscrews can slide on the bone surface during placement. The software program (2.5-dimensional software) in this study combines 2-dimensional cephalograms with 3D virtual dental models. This software is an effective and efficient alternative to 3D software when 3D computed tomography data are not available. To confidently and safely place a miniplate with screw fixation, a simple customized guide for an orthodontic miniplate was introduced. The use of a custom-made, rigid guide when placing miniplates will minimize complications such as vertical mislocation or slippage of the miniplate during placement. Copyright © 2014 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

Advances in the Dynallax solid-state dynamic parallax barrier autostereoscopic visualization display system.

PubMed

Peterka, Tom; Kooima, Robert L; Sandin, Daniel J; Johnson, Andrew; Leigh, Jason; DeFanti, Thomas A

2008-01-01

A solid-state dynamic parallax barrier autostereoscopic display mitigates some of the restrictions present in static barrier systems, such as fixed view-distance range, slow response to head movements, and fixed stereo operating mode. By dynamically varying barrier parameters in real time, viewers may move closer to the display and move faster laterally than with a static barrier system, and the display can switch between 3D and 2D modes by disabling the barrier on a per-pixel basis. Moreover, Dynallax can output four independent eye channels when two viewers are present, and both head-tracked viewers receive an independent pair of left-eye and right-eye perspective views based on their position in 3D space. The display device is constructed by using a dual-stacked LCD monitor where a dynamic barrier is rendered on the front display and a modulated virtual environment composed of two or four channels is rendered on the rear display. Dynallax was recently demonstrated in a small-scale head-tracked prototype system. This paper summarizes the concepts presented earlier, extends the discussion of various topics, and presents recent improvements to the system.

Distance Learning for Students with Special Needs through 3D Virtual Learning

ERIC Educational Resources Information Center

Laffey, James M.; Stichter, Janine; Galyen, Krista

2014-01-01

iSocial is a 3D Virtual Learning Environment (3D VLE) to develop social competency for students who have been identified with High-Functioning Autism Spectrum Disorders. The motivation for developing a 3D VLE is to improve access to special needs curriculum for students who live in rural or small school districts. The paper first describes a…

3D virtual environment of Taman Mini Indonesia Indah in a web

NASA Astrophysics Data System (ADS)

Wardijono, B. A.; Wardhani, I. P.; Chandra, Y. I.; Pamungkas, B. U. G.

2018-05-01

Taman Mini Indonesia Indah known as TMII is a largest recreational park based on culture in Indonesia. This park has 250 acres that consist of houses from provinces in Indonesia. In TMII, there are traditional houses of the various provinces in Indonesia. The official website of TMII has informed the traditional houses, but the information was limited to public. To provide information more detail about TMII to the public, this research aims to create and develop virtual traditional houses as 3d graphics models and show it via website. The Virtual Reality (VR) technology was used to display the visualization of the TMII and the surrounding environment. This research used Blender software to create the 3D models and Unity3D software to make virtual reality models that can be showed on a web. This research has successfully created 33 virtual traditional houses of province in Indonesia. The texture of traditional house was taken from original to make the culture house realistic. The result of this research was the website of TMII including virtual culture houses that can be displayed through the web browser. The website consists of virtual environment scenes and internet user can walkthrough and navigates inside the scenes.

Using a cVEP-Based Brain-Computer Interface to Control a Virtual Agent.

PubMed

Riechmann, Hannes; Finke, Andrea; Ritter, Helge

2016-06-01

Brain-computer interfaces provide a means for controlling a device by brain activity alone. One major drawback of noninvasive BCIs is their low information transfer rate, obstructing a wider deployment outside the lab. BCIs based on codebook visually evoked potentials (cVEP) outperform all other state-of-the-art systems in that regard. Previous work investigated cVEPs for spelling applications. We present the first cVEP-based BCI for use in real-world settings to accomplish everyday tasks such as navigation or action selection. To this end, we developed and evaluated a cVEP-based on-line BCI that controls a virtual agent in a simulated, but realistic, 3-D kitchen scenario. We show that cVEPs can be reliably triggered with stimuli in less restricted presentation schemes, such as on dynamic, changing backgrounds. We introduce a novel, dynamic repetition algorithm that allows for optimizing the balance between accuracy and speed individually for each user. Using these novel mechanisms in a 12-command cVEP-BCI in the 3-D simulation results in ITRs of 50 bits/min on average and 68 bits/min maximum. Thus, this work supports the notion of cVEP-BCIs as a particular fast and robust approach suitable for real-world use.

Full Immersive Virtual Environment Cave[TM] in Chemistry Education

ERIC Educational Resources Information Center

Limniou, M.; Roberts, D.; Papadopoulos, N.

2008-01-01

By comparing two-dimensional (2D) chemical animations designed for computer's desktop with three-dimensional (3D) chemical animations designed for the full immersive virtual reality environment CAVE[TM] we studied how virtual reality environments could raise student's interest and motivation for learning. By using the 3ds max[TM], we can visualize…

A Collaborative Virtual Environment for Situated Language Learning Using VEC3D

ERIC Educational Resources Information Center

Shih, Ya-Chun; Yang, Mau-Tsuen

2008-01-01

A 3D virtually synchronous communication architecture for situated language learning has been designed to foster communicative competence among undergraduate students who have studied English as a foreign language (EFL). We present an innovative approach that offers better e-learning than the previous virtual reality educational applications. The…

Social Presence and Motivation in a Three-Dimensional Virtual World: An Explanatory Study

ERIC Educational Resources Information Center

Yilmaz, Rabia M.; Topu, F. Burcu; Goktas, Yuksel; Coban, Murat

2013-01-01

Three-dimensional (3-D) virtual worlds differ from other learning environments in their similarity to real life, providing opportunities for more effective communication and interaction. With these features, 3-D virtual worlds possess considerable potential to enhance learning opportunities. For effective learning, the users' motivation levels and…

Application of two segmentation protocols during the processing of virtual images in rapid prototyping: ex vivo study with human dry mandibles.

PubMed

Ferraz, Eduardo Gomes; Andrade, Lucio Costa Safira; dos Santos, Aline Rode; Torregrossa, Vinicius Rabelo; Rubira-Bullen, Izabel Regina Fischer; Sarmento, Viviane Almeida

2013-12-01

The aim of this study was to evaluate the accuracy of virtual three-dimensional (3D) reconstructions of human dry mandibles, produced from two segmentation protocols ("outline only" and "all-boundary lines"). Twenty virtual three-dimensional (3D) images were built from computed tomography exam (CT) of 10 dry mandibles, in which linear measurements between anatomical landmarks were obtained and compared to an error probability of 5 %. The results showed no statistically significant difference among the dry mandibles and the virtual 3D reconstructions produced from segmentation protocols tested (p = 0,24). During the designing of a virtual 3D reconstruction, both "outline only" and "all-boundary lines" segmentation protocols can be used. Virtual processing of CT images is the most complex stage during the manufacture of the biomodel. Establishing a better protocol during this phase allows the construction of a biomodel with characteristics that are closer to the original anatomical structures. This is essential to ensure a correct preoperative planning and a suitable treatment.

Virtual performer: single camera 3D measuring system for interaction in virtual space

NASA Astrophysics Data System (ADS)

Sakamoto, Kunio; Taneji, Shoto

2006-10-01

The authors developed interaction media systems in the 3D virtual space. In these systems, the musician virtually plays an instrument like the theremin in the virtual space or the performer plays a show using the virtual character such as a puppet. This interactive virtual media system consists of the image capture, measuring performer's position, detecting and recognizing motions and synthesizing video image using the personal computer. In this paper, we propose some applications of interaction media systems; a virtual musical instrument and superimposing CG character. Moreover, this paper describes the measuring method of the positions of the performer, his/her head and both eyes using a single camera.

Dynamic Flight Maneuvering Using Virtual Control Surfaces Generated by Trapped Vorticity

DTIC Science & Technology

2010-12-01

of a modified Dragon Eye UAV. These tests illustrated the possibility of controlled flight using open-loop flow control actuators. Future research...2 -1 0 1 2 z ( cm ) 0 1 2 3 4 5 1 2 3 4 5 Time (s)  (d eg ) Figure II-1 Step command tracking in plung: ideal reference model response...experimental results. The experimental results were obtained with the ball screws locked in position so that the wing model was only allowed to pitch

Development, Deployment, and Assessment of Dynamic Geological and Geophysical Models Using the Google Earth APP and API: Implications for Undergraduate Education in the Earth and Planetary Sciences

NASA Astrophysics Data System (ADS)

de Paor, D. G.; Whitmeyer, S. J.; Gobert, J.

2009-12-01

We previously reported on innovative techniques for presenting data on virtual globes such as Google Earth using emergent Collada models that reveal subsurface geology and geophysics. We here present several new and enhanced models and linked lesson plans to aid deployment in undergraduate geoscience courses, along with preliminary results from our assessment of their effectiveness. The new Collada models are created with Google SketchUp, Bonzai3D, and MeshLab software, and are grouped to cover (i) small scale field mapping areas; (ii) regional scale studies of the North Atlantic Ocean Basin, the Appalachian Orogen, and the Pacific Ring of Fire; and (iii) global scale studies of terrestrial planets, moons, and asteroids. Enhancements include emergent block models with three-dimensional surface topography; models that conserve structural orientation data; interactive virtual specimens; models that animate plate movements on the virtual globe; exploded 3-D views of planetary mantles and cores; and server-generated dynamic KML. We tested volunteer students and professors using Silverback monitoring software, think-aloud verbalizations, and questionnaires designed to assess their understanding of the underlying geo-scientific phenomena. With the aid of a cohort of instructors across the U.S., we are continuing to assess areas in which users encounter difficulties with both the software and geoscientific concepts. Preliminary results suggest that it is easy to overestimate the computer expertise of novice users even when they are content knowledge experts (i.e., instructors), and that a detailed introduction to virtual globe manipulation is essential before moving on to geoscience applications. Tasks that seem trivial to developers may present barriers to non-technical users and technicalities that challenge instructors may block adoption in the classroom. We have developed new models using the Google Earth API which permits enhanced interaction and dynamic feedback and are assessing their relative merits versus the Google Earth APP. Overall, test students and professors value the models very highly. There are clear pedagogical opportunities for using materials such as these to create engaging in-course research opportunities for undergraduates.

[Application of 3D virtual reality technology with multi-modality fusion in resection of glioma located in central sulcus region].

PubMed

Chen, T N; Yin, X T; Li, X G; Zhao, J; Wang, L; Mu, N; Ma, K; Huo, K; Liu, D; Gao, B Y; Feng, H; Li, F

2018-05-08

Objective: To explore the clinical and teaching application value of virtual reality technology in preoperative planning and intraoperative guide of glioma located in central sulcus region. Method: Ten patients with glioma in the central sulcus region were proposed to surgical treatment. The neuro-imaging data, including CT, CTA, DSA, MRI, fMRI were input to 3dgo sczhry workstation for image fusion and 3D reconstruction. Spatial relationships between the lesions and the surrounding structures on the virtual reality image were obtained. These images were applied to the operative approach design, operation process simulation, intraoperative auxiliary decision and the training of specialist physician. Results: Intraoperative founding of 10 patients were highly consistent with preoperative simulation with virtual reality technology. Preoperative 3D reconstruction virtual reality images improved the feasibility of operation planning and operation accuracy. This technology had not only shown the advantages for neurological function protection and lesion resection during surgery, but also improved the training efficiency and effectiveness of dedicated physician by turning the abstract comprehension to virtual reality. Conclusion: Image fusion and 3D reconstruction based virtual reality technology in glioma resection is helpful for formulating the operation plan, improving the operation safety, increasing the total resection rate, and facilitating the teaching and training of the specialist physician.

High-Resolution Large-Field-of-View Three-Dimensional Hologram Display System and Method Thereof

NASA Technical Reports Server (NTRS)

Chao, Tien-Hsin (Inventor); Mintz, Frederick W. (Inventor); Tsou, Peter (Inventor); Bryant, Nevin A. (Inventor)

2001-01-01

A real-time, dynamic, free space-virtual reality, 3-D image display system is enabled by using a unique form of Aerogel as the primary display media. A preferred embodiment of this system comprises a 3-D mosaic topographic map which is displayed by fusing four projected hologram images. In this embodiment, four holographic images are projected from four separate holograms. Each holographic image subtends a quadrant of the 4(pi) solid angle. By fusing these four holographic images, a static 3-D image such as a featured terrain map would be visible for 360 deg in the horizontal plane and 180 deg in the vertical plane. An input, either acquired by 3-D image sensor or generated by computer animation, is first converted into a 2-D computer generated hologram (CGH). This CGH is then downloaded into large liquid crystal (LC) panel. A laser projector illuminates the CGH-filled LC panel and generates and displays a real 3-D image in the Aerogel matrix.

Virtual and Printed 3D Models for Teaching Crystal Symmetry and Point Groups

ERIC Educational Resources Information Center

Casas, Lluís; Estop, Euge`nia

2015-01-01

Both, virtual and printed 3D crystal models can help students and teachers deal with chemical education topics such as symmetry and point groups. In the present paper, two freely downloadable tools (interactive PDF files and a mobile app) are presented as examples of the application of 3D design to study point-symmetry. The use of 3D printing to…

3D Virtual Worlds as Art Media and Exhibition Arenas: Students' Responses and Challenges in Contemporary Art Education

ERIC Educational Resources Information Center

Lu, Lilly

2013-01-01

3D virtual worlds (3D VWs) are considered one of the emerging learning spaces of the 21st century; however, few empirical studies have investigated educational applications and student learning aspects in art education. This study focused on students' responses to and challenges with 3D VWs in both aspects. The findings show that most participants…

Virtual acoustics displays

NASA Technical Reports Server (NTRS)

Wenzel, Elizabeth M.; Fisher, Scott S.; Stone, Philip K.; Foster, Scott H.

1991-01-01

The real time acoustic display capabilities are described which were developed for the Virtual Environment Workstation (VIEW) Project at NASA-Ames. The acoustic display is capable of generating localized acoustic cues in real time over headphones. An auditory symbology, a related collection of representational auditory 'objects' or 'icons', can be designed using ACE (Auditory Cue Editor), which links both discrete and continuously varying acoustic parameters with information or events in the display. During a given display scenario, the symbology can be dynamically coordinated in real time with 3-D visual objects, speech, and gestural displays. The types of displays feasible with the system range from simple warnings and alarms to the acoustic representation of multidimensional data or events.

Virtual acoustics displays

NASA Astrophysics Data System (ADS)

Wenzel, Elizabeth M.; Fisher, Scott S.; Stone, Philip K.; Foster, Scott H.

1991-03-01

The real time acoustic display capabilities are described which were developed for the Virtual Environment Workstation (VIEW) Project at NASA-Ames. The acoustic display is capable of generating localized acoustic cues in real time over headphones. An auditory symbology, a related collection of representational auditory 'objects' or 'icons', can be designed using ACE (Auditory Cue Editor), which links both discrete and continuously varying acoustic parameters with information or events in the display. During a given display scenario, the symbology can be dynamically coordinated in real time with 3-D visual objects, speech, and gestural displays. The types of displays feasible with the system range from simple warnings and alarms to the acoustic representation of multidimensional data or events.

Quantitative 3-D imaging topogrammetry for telemedicine applications

NASA Technical Reports Server (NTRS)

Altschuler, Bruce R.

1994-01-01

The technology to reliably transmit high-resolution visual imagery over short to medium distances in real time has led to the serious considerations of the use of telemedicine, telepresence, and telerobotics in the delivery of health care. These concepts may involve, and evolve toward: consultation from remote expert teaching centers; diagnosis; triage; real-time remote advice to the surgeon; and real-time remote surgical instrument manipulation (telerobotics with virtual reality). Further extrapolation leads to teledesign and telereplication of spare surgical parts through quantitative teleimaging of 3-D surfaces tied to CAD/CAM devices and an artificially intelligent archival data base of 'normal' shapes. The ability to generate 'topogrames' or 3-D surface numerical tables of coordinate values capable of creating computer-generated virtual holographic-like displays, machine part replication, and statistical diagnostic shape assessment is critical to the progression of telemedicine. Any virtual reality simulation will remain in 'video-game' realm until realistic dimensional and spatial relational inputs from real measurements in vivo during surgeries are added to an ever-growing statistical data archive. The challenges of managing and interpreting this 3-D data base, which would include radiographic and surface quantitative data, are considerable. As technology drives toward dynamic and continuous 3-D surface measurements, presenting millions of X, Y, Z data points per second of flexing, stretching, moving human organs, the knowledge base and interpretive capabilities of 'brilliant robots' to work as a surgeon's tireless assistants becomes imaginable. The brilliant robot would 'see' what the surgeon sees--and more, for the robot could quantify its 3-D sensing and would 'see' in a wider spectral range than humans, and could zoom its 'eyes' from the macro world to long-distance microscopy. Unerring robot hands could rapidly perform machine-aided suturing with precision micro-sewing machines, splice neural connections with laser welds, micro-bore through constricted vessels, and computer combine ultrasound, microradiography, and 3-D mini-borescopes to quickly assess and trace vascular problems in situ. The spatial relationships between organs, robotic arms, and end-effector diagnostic, manipulative, and surgical instruments would be constantly monitored by the robot 'brain' using inputs from its multiple 3-D quantitative 'eyes' remote sensing, as well as by contact and proximity force measuring devices. Methods to create accurate and quantitative 3-D topograms at continuous video data rates are described.

Rationally designed peptide nanosponges for cell-based cancer therapy.

PubMed

Wang, Hongwang; Yapa, Asanka S; Kariyawasam, Nilusha L; Shrestha, Tej B; Kalubowilage, Madumali; Wendel, Sebastian O; Yu, Jing; Pyle, Marla; Basel, Matthew T; Malalasekera, Aruni P; Toledo, Yubisela; Ortega, Raquel; Thapa, Prem S; Huang, Hongzhou; Sun, Susan X; Smith, Paul E; Troyer, Deryl L; Bossmann, Stefan H

2017-11-01

A novel type of supramolecular aggregate, named a "nanosponge" was synthesized through the interaction of novel supramolecular building blocks with trigonal geometry. The cholesterol-(K/D) n DEVDGC) 3 -trimaleimide unit consists of a trigonal maleimide linker to which homopeptides (either K or D) of variable lengths (n=5, 10, 15, 20) and a consensus sequence for executioner caspases (DEVDGC) are added via Michael addition. Upon mixing in aqueous buffer cholesterol-(K) n DEVDGC) 3 -trimaleimides and a 1:1 mixture of cholesterol-(K/D) n DEVDGC) 3 -trimaleimides form stable nanosponges, whereas cholesterol-(D) n DEVDGC) 3 -trimaleimide is unable to form supramolecular aggregates with itself. The structure of the novel nanosponges was investigated through explicit solvent and then coarse-grained molecular dynamics (MD) simulations. The nanosponges are between 80 nm and several micrometers in diameters and virtually non-toxic to monocyte/macrophage-like cells. Copyright © 2017 Elsevier Inc. All rights reserved.

Integrated bronchoscopic video tracking and 3D CT registration for virtual bronchoscopy

NASA Astrophysics Data System (ADS)

Higgins, William E.; Helferty, James P.; Padfield, Dirk R.

2003-05-01

Lung cancer assessment involves an initial evaluation of 3D CT image data followed by interventional bronchoscopy. The physician, with only a mental image inferred from the 3D CT data, must guide the bronchoscope through the bronchial tree to sites of interest. Unfortunately, this procedure depends heavily on the physician's ability to mentally reconstruct the 3D position of the bronchoscope within the airways. In order to assist physicians in performing biopsies of interest, we have developed a method that integrates live bronchoscopic video tracking and 3D CT registration. The proposed method is integrated into a system we have been devising for virtual-bronchoscopic analysis and guidance for lung-cancer assessment. Previously, the system relied on a method that only used registration of the live bronchoscopic video to corresponding virtual endoluminal views derived from the 3D CT data. This procedure only performs the registration at manually selected sites; it does not draw upon the motion information inherent in the bronchoscopic video. Further, the registration procedure is slow. The proposed method has the following advantages: (1) it tracks the 3D motion of the bronchoscope using the bronchoscopic video; (2) it uses the tracked 3D trajectory of the bronchoscope to assist in locating sites in the 3D CT "virtual world" to perform the registration. In addition, the method incorporates techniques to: (1) detect and exclude corrupted video frames (to help make the video tracking more robust); (2) accelerate the computation of the many 3D virtual endoluminal renderings (thus, speeding up the registration process). We have tested the integrated tracking-registration method on a human airway-tree phantom and on real human data.

Molecular modeling, simulation and virtual screening of MurD ligase protein from Salmonella typhimurium LT2.

PubMed

Samal, Himanshu Bhusan; Das, Jugal Kishore; Mahapatra, Rajani Kanta; Suar, Mrutyunjay

2015-01-01

The Mur enzymes of the peptidoglycan biosynthesis pathway constitute ideal targets for the design of new classes of antimicrobial inhibitors in Gram-negative bacteria. We built a homology model of MurD of Salmonella typhimurium LT2 using MODELLER (9v12) software. 'The homology model was subjected to energy minimization by molecular dynamics (MD) simulation study with GROMACS software for a simulation time of 20 ns in water environment. The model was subjected for virtual screening study from the Zinc Database using Dockblaster software. Inhibition assay for the best inhibitor, 3-(amino methyl)-n-(4-methoxyphenyl) aniline, by flow cytometric analysis revealed the effective inhibition of peptidoglycan biosynthesis. Results from this study provide new insights for the molecular understanding and development of new antibacterial drugs against the pathogen. Copyright © 2015 Elsevier Inc. All rights reserved.

Integration of oncologic margins in three-dimensional virtual planning for head and neck surgery, including a validation of the software pathway.

PubMed

Kraeima, Joep; Schepers, Rutger H; van Ooijen, Peter M A; Steenbakkers, Roel J H M; Roodenburg, Jan L N; Witjes, Max J H

2015-10-01

Three-dimensional (3D) virtual planning of reconstructive surgery, after resection, is a frequently used method for improving accuracy and predictability. However, when applied to malignant cases, the planning of the oncologic resection margins is difficult due to visualisation of tumours in the current 3D planning. Embedding tumour delineation on a magnetic resonance image, similar to the routinely performed radiotherapeutic contouring of tumours, is expected to provide better margin planning. A new software pathway was developed for embedding tumour delineation on magnetic resonance imaging (MRI) within the 3D virtual surgical planning. The software pathway was validated by the use of five bovine cadavers implanted with phantom tumour objects. MRI and computed tomography (CT) images were fused and the tumour was delineated using radiation oncology software. This data was converted to the 3D virtual planning software by means of a conversion algorithm. Tumour volumes and localization were determined in both software stages for comparison analysis. The approach was applied to three clinical cases. A conversion algorithm was developed to translate the tumour delineation data to the 3D virtual plan environment. The average difference in volume of the tumours was 1.7%. This study reports a validated software pathway, providing multi-modality image fusion for 3D virtual surgical planning. Copyright © 2015 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

An Effective Construction Method of Modular Manipulator 3D Virtual Simulation Platform

NASA Astrophysics Data System (ADS)

Li, Xianhua; Lv, Lei; Sheng, Rui; Sun, Qing; Zhang, Leigang

2018-06-01

This work discusses about a fast and efficient method of constructing an open 3D manipulator virtual simulation platform which make it easier for teachers and students to learn about positive and inverse kinematics of a robot manipulator. The method was carried out using MATLAB. In which, the Robotics Toolbox, MATLAB GUI and 3D animation with the help of modelling using SolidWorks, were fully applied to produce a good visualization of the system. The advantages of using quickly build is its powerful function of the input and output and its ability to simulate a 3D manipulator realistically. In this article, a Schunk six DOF modular manipulator was constructed by the author's research group to be used as example. The implementation steps of this method was detailed described, and thereafter, a high-level open and realistic visualization manipulator 3D virtual simulation platform was achieved. With the graphs obtained from simulation, the test results show that the manipulator 3D virtual simulation platform can be constructed quickly with good usability and high maneuverability, and it can meet the needs of scientific research and teaching.

Incidental Learning in 3D Virtual Environments: Relationships to Learning Style, Digital Literacy and Information Display

ERIC Educational Resources Information Center

Thomas, Wayne W.; Boechler, Patricia M.

2014-01-01

With teachers taking more interest in utilizing 3D virtual environments for educational purposes, research is needed to understand how learners perceive and process information within virtual environments (Eschenbrenner, Nah, & Siau, 2008). In this study, the authors sought to determine if learning style or digital literacy predict incidental…

Teaching Physics to Deaf College Students in a 3-D Virtual Lab

ERIC Educational Resources Information Center

Robinson, Vicki

2013-01-01

Virtual worlds are used in many educational and business applications. At the National Technical Institute for the Deaf at Rochester Institute of Technology (NTID/RIT), deaf college students are introduced to the virtual world of Second Life, which is a 3-D immersive, interactive environment, accessed through computer software. NTID students use…

GEARS a 3D Virtual Learning Environment and Virtual Social and Educational World Used in Online Secondary Schools

ERIC Educational Resources Information Center

Barkand, Jonathan; Kush, Joseph

2009-01-01

Virtual Learning Environments (VLEs) are becoming increasingly popular in online education environments and have multiple pedagogical advantages over more traditional approaches to education. VLEs include 3D worlds where students can engage in simulated learning activities such as Second Life. According to Claudia L'Amoreaux at Linden Lab, "at…

Virtual reality: Avatars in human spaceflight training

NASA Astrophysics Data System (ADS)

Osterlund, Jeffrey; Lawrence, Brad

2012-02-01

With the advancements in high spatial and temporal resolution graphics, along with advancements in 3D display capabilities to model, simulate, and analyze human-to-machine interfaces and interactions, the world of virtual environments is being used to develop everything from gaming, movie special affects and animations to the design of automobiles. The use of multiple object motion capture technology and digital human tools in aerospace has demonstrated to be a more cost effective alternative to the cost of physical prototypes, provides a more efficient, flexible and responsive environment to changes in the design and training, and provides early human factors considerations concerning the operation of a complex launch vehicle or spacecraft. United Space Alliance (USA) has deployed this technique and tool under Research and Development (R&D) activities on both spacecraft assembly and ground processing operations design and training on the Orion Crew Module. USA utilizes specialized products that were chosen based on functionality, including software and fixed based hardware (e.g., infrared and visible red cameras), along with cyber gloves to ensure fine motor dexterity of the hands. The key findings of the R&D were: mock-ups should be built to not obstruct cameras from markers being tracked; a mock-up toolkit be assembled to facilitate dynamic design changes; markers should be placed in accurate positions on humans and flight hardware to help with tracking; 3D models used in the virtual environment be striped of non-essential data; high computational capable workstations are required to handle the large model data sets; and Technology Interchange Meetings with vendors and other industries also utilizing virtual reality applications need to occur on a continual basis enabling USA to maintain its leading edge within this technology. Parameters of interest and benefit in human spaceflight simulation training that utilizes virtual reality technologies are to familiarize and assess operational processes, allow the ability to train virtually, experiment with "what if" scenarios, and expedite immediate changes to validate the design implementation are all parameters of interest in human spaceflight. Training benefits encompass providing 3D animation for post-training assessment, placement of avatars within 3D replicated work environments in assembling or processing hardware, offering various viewpoints of processes viewed and assessed giving the evaluators the ability to assess task feasibility and identify potential support equipment needs; and provide human factors determinations, such as reach, visibility, and accessibility. Multiple object motion capture technology provides an effective tool to train and assess ergonomic risks, simulations for determination of negative interactions between technicians and their proposed workspaces, and evaluation of spaceflight systems prior to, and as part of, the design process to contain costs and reduce schedule delays.

Knowledge and Valorization of Historical Sites Through 3d Documentation and Modeling

NASA Astrophysics Data System (ADS)

Farella, E.; Menna, F.; Nocerino, E.; Morabito, D.; Remondino, F.; Campi, M.

2016-06-01

The paper presents the first results of an interdisciplinary project related to the 3D documentation, dissemination, valorization and digital access of archeological sites. Beside the mere 3D documentation aim, the project has two goals: (i) to easily explore and share via web references and results of the interdisciplinary work, including the interpretative process and the final reconstruction of the remains; (ii) to promote and valorize archaeological areas using reality-based 3D data and Virtual Reality devices. This method has been verified on the ruins of the archeological site of Pausilypon, a maritime villa of Roman period (Naples, Italy). Using Unity3D, the virtual tour of the heritage site was integrated and enriched with the surveyed 3D data, text documents, CAAD reconstruction hypotheses, drawings, photos, etc. In this way, starting from the actual appearance of the ruins (panoramic images), passing through the 3D digital surveying models and several other historical information, the user is able to access virtual contents and reconstructed scenarios, all in a single virtual, interactive and immersive environment. These contents and scenarios allow to derive documentation and geometrical information, understand the site, perform analyses, see interpretative processes, communicate historical information and valorize the heritage location.

The development of a virtual 3D model of the renal corpuscle from serial histological sections for E-learning environments.

PubMed

Roth, Jeremy A; Wilson, Timothy D; Sandig, Martin

2015-01-01

Histology is a core subject in the anatomical sciences where learners are challenged to interpret two-dimensional (2D) information (gained from histological sections) to extrapolate and understand the three-dimensional (3D) morphology of cells, tissues, and organs. In gross anatomical education 3D models and learning tools have been associated with improved learning outcomes, but similar tools have not been created for histology education to visualize complex cellular structure-function relationships. This study outlines steps in creating a virtual 3D model of the renal corpuscle from serial, semi-thin, histological sections obtained from epoxy resin-embedded kidney tissue. The virtual renal corpuscle model was generated by digital segmentation to identify: Bowman's capsule, nuclei of epithelial cells in the parietal capsule, afferent arteriole, efferent arteriole, proximal convoluted tubule, distal convoluted tubule, glomerular capillaries, podocyte nuclei, nuclei of extraglomerular mesangial cells, nuclei of epithelial cells of the macula densa in the distal convoluted tubule. In addition to the imported images of the original sections the software generates, and allows for visualization of, images of virtual sections generated in any desired orientation, thus serving as a "virtual microtome". These sections can be viewed separately or with the 3D model in transparency. This approach allows for the development of interactive e-learning tools designed to enhance histology education of microscopic structures with complex cellular interrelationships. Future studies will focus on testing the efficacy of interactive virtual 3D models for histology education. © 2015 American Association of Anatomists.

Openwebglobe 2: Visualization of Complex 3D-GEODATA in the (mobile) Webbrowser

NASA Astrophysics Data System (ADS)

Christen, M.

2016-06-01

Providing worldwide high resolution data for virtual globes consists of compute and storage intense tasks for processing data. Furthermore, rendering complex 3D-Geodata, such as 3D-City models with an extremely high polygon count and a vast amount of textures at interactive framerates is still a very challenging task, especially on mobile devices. This paper presents an approach for processing, caching and serving massive geospatial data in a cloud-based environment for large scale, out-of-core, highly scalable 3D scene rendering on a web based virtual globe. Cloud computing is used for processing large amounts of geospatial data and also for providing 2D and 3D map data to a large amount of (mobile) web clients. In this paper the approach for processing, rendering and caching very large datasets in the currently developed virtual globe "OpenWebGlobe 2" is shown, which displays 3D-Geodata on nearly every device.

World Wind: NASA's Virtual Globe

NASA Astrophysics Data System (ADS)

Hogan, P.

2007-12-01

Virtual globes have set the standard for information exchange. Once you've experienced the visually rich and highly compelling nature of data delivered via virtual globes with their highly engaging context of 3D, it's hard to go back to a flat 2D world. Just as the sawbones of not-too-long-ago have given way to sophisticated surgical operating theater, today's medium for information exchange is just beginning to leap from the staid chalkboards and remote libraries to fingertip navigable 3D worlds. How we harness this technology to serve a world inundated with information will describe the quality of our future. Our instincts for discovery and entertainment urge us on. There's so much we could know if the world's knowledge was presented to us in its natural context. Virtual globes are almost magical in their ability to reveal natural wonders. Anyone flying along a chain of volcanoes, a mid-ocean ridge or deep ocean trench, while simultaneously seeing the different depths to the history of earthquakes in those areas, will be delighted to sense Earth's dynamic nature in a way that would otherwise take several paragraphs of "boring" text. The sophisticated concepts related to global climate change would be far more comprehensible when experienced via a virtual globe. There is a large universe of public and private geospatial data sets that virtual globes can bring to light. The benefit derived from access to this data within virtual globes represents a significant return on investment for government, industry, the general public, and especially in the realm of education. Data access remains a key issue. Just as the highway infrastructure allows unimpeded access from point A to point B, an open standards-based infrastructure for data access allows virtual globes to exchange data in the most efficient manner possible. This data can be either free or proprietary. The Open Geospatial Consortium is providing the leadership necessary for this open standards-based data access infrastructure. The open-source community plays a crucial role in advancing virtual globe technology. This world community identifies, tracks and resolves technical problems, suggests new features and source code modifications, and often provides high-resolution data sets and other types of user-generated content, all while extending the functionality of virtual globe technology. NASA World Wind is one example of open source virtual globe technology that provides the world with the ability to build any desired functionality and make any desired data accessible.

Three-Dimensional Sensor Common Operating Picture (3-D Sensor COP)

DTIC Science & Technology

2017-01-01

created. Additionally, a 3-D model of the sensor itself can be created. Using these 3-D models, along with emerging virtual and augmented reality tools...augmented reality 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT UU 18. NUMBER OF PAGES 20 19a...iii Contents List of Figures iv 1. Introduction 1 2. The 3-D Sensor COP 2 3. Virtual Sensor Placement 7 4. Conclusions 10 5. References 11

The Effect of the Use of the 3-D Multi-User Virtual Environment "Second Life" on Student Motivation and Language Proficiency in Courses of Spanish as a Foreign Language

ERIC Educational Resources Information Center

Pares-Toral, Maria T.

2013-01-01

The ever increasing popularity of virtual worlds, also known as 3-D multi-user virtual environments (MUVEs) or simply virtual worlds provides language instructors with a new tool they can exploit in their courses. For now, "Second Life" is one of the most popular MUVEs used for teaching and learning, and although "Second Life"…

EXPLORING ENVIRONMENTAL DATA IN A HIGHLY IMMERSIVE VIRTUAL REALITY ENVIRONMENT

EPA Science Inventory

Geography inherently fills a 3D space and yet we struggle with displaying geography using, primaarily, 2D display devices. Virtual environments offer a more realistically-dimensioned display space and this is being realized in the expanding area of research on 3D Geographic Infor...

Virtual Jupiter - Real Learning

NASA Astrophysics Data System (ADS)

Ruzhitskaya, Lanika; Speck, A.; Laffey, J.

2010-01-01

How many earthlings went to visit Jupiter? None. How many students visited virtual Jupiter to fulfill their introductory astronomy courses’ requirements? Within next six months over 100 students from University of Missouri will get a chance to explore the planet and its Galilean Moons using a 3D virtual environment created especially for them to learn Kepler's and Newton's laws, eclipses, parallax, and other concepts in astronomy. The virtual world of Jupiter system is a unique 3D environment that allows students to learn course material - physical laws and concepts in astronomy - while engaging them into exploration of the Jupiter's system, encouraging their imagination, curiosity, and motivation. The virtual learning environment let students to work individually or collaborate with their teammates. The 3D world is also a great opportunity for research in astronomy education to investigate impact of social interaction, gaming features, and use of manipulatives offered by a learning tool on students’ motivation and learning outcomes. Use of 3D environment is also a valuable source for exploration of how the learners’ spatial awareness can be enhanced by working in 3-dimensional environment.

The use of physical and virtual manipulatives in an undergraduate mechanical engineering (Dynamics) course

NASA Astrophysics Data System (ADS)

Pan, Edward A.

Science, technology, engineering, and mathematics (STEM) education is a national focus. Engineering education, as part of STEM education, needs to adapt to meet the needs of the nation in a rapidly changing world. Using computer-based visualization tools and corresponding 3D printed physical objects may help nontraditional students succeed in engineering classes. This dissertation investigated how adding physical or virtual learning objects (called manipulatives) to courses that require mental visualization of mechanical systems can aid student performance. Dynamics is one such course, and tends to be taught using lecture and textbooks with static diagrams of moving systems. Students often fail to solve the problems correctly and an inability to mentally visualize the system can contribute to student difficulties. This study found no differences between treatment groups on quantitative measures of spatial ability and conceptual knowledge. There were differences between treatments on measures of mechanical reasoning ability, in favor of the use of physical and virtual manipulatives over static diagrams alone. There were no major differences in student performance between the use of physical and virtual manipulatives. Students used the physical and virtual manipulatives to test their theories about how the machines worked, however their actual time handling the manipulatives was extremely limited relative to the amount of time they spent working on the problems. Students used the physical and virtual manipulatives as visual aids when communicating about the problem with their partners, and this behavior was also seen with Traditional group students who had to use the static diagrams and gesture instead. The explanations students gave for how the machines worked provided evidence of mental simulation; however, their causal chain analyses were often flawed, probably due to attempts to decrease cognitive load. Student opinions about the static diagrams and dynamic models varied by type of model (static, physical, virtual), but were generally favorable. The Traditional group students, however, indicated that the lack of adequate representation of motion in the static diagrams was a problem, and wished they had access to the physical and virtual models.

Augmented reality glass-free three-dimensional display with the stereo camera

NASA Astrophysics Data System (ADS)

Pang, Bo; Sang, Xinzhu; Chen, Duo; Xing, Shujun; Yu, Xunbo; Yan, Binbin; Wang, Kuiru; Yu, Chongxiu

2017-10-01

An improved method for Augmented Reality (AR) glass-free three-dimensional (3D) display based on stereo camera used for presenting parallax contents from different angle with lenticular lens array is proposed. Compared with the previous implementation method of AR techniques based on two-dimensional (2D) panel display with only one viewpoint, the proposed method can realize glass-free 3D display of virtual objects and real scene with 32 virtual viewpoints. Accordingly, viewers can get abundant 3D stereo information from different viewing angles based on binocular parallax. Experimental results show that this improved method based on stereo camera can realize AR glass-free 3D display, and both of virtual objects and real scene have realistic and obvious stereo performance.

2D and 3D virtual interactive laboratories of physics on Unity platform

NASA Astrophysics Data System (ADS)

González, J. D.; Escobar, J. H.; Sánchez, H.; De la Hoz, J.; Beltrán, J. R.

2017-12-01

Using the cross-platform game engine Unity, we develop virtual laboratories for PC, consoles, mobile devices and website as an innovative tool to study physics. There is extensive uptake of ICT in the teaching of science and its impact on the learning, and considering the limited availability of laboratories for physics teaching and the difficulties this causes in the learning of school students, we design the virtual laboratories to enhance studentâĂŹs knowledge of concepts in physics. To achieve this goal, we use Unity due to provide support bump mapping, reflection mapping, parallax mapping, dynamics shadows using shadows maps, full-screen post-processing effects and render-to-texture. Unity can use the best variant for the current video hardware and, if none are compatible, to use an alternative shader that may sacrifice features for performance. The control over delivery to mobile devices, web browsers, consoles and desktops is the main reason Unity is the best option among the same kind cross-platform. Supported platforms include Android, Apple TV, Linux, iOS, Nintendo 3DS line, macOS, PlayStation 4, Windows Phone 8, Wii but also an asset server and Nvidia’s PhysX physics engine which is the most relevant tool on Unity for our PhysLab.

CaveCAD: a tool for architectural design in immersive virtual environments

NASA Astrophysics Data System (ADS)

Schulze, Jürgen P.; Hughes, Cathleen E.; Zhang, Lelin; Edelstein, Eve; Macagno, Eduardo

2014-02-01

Existing 3D modeling tools were designed to run on desktop computers with monitor, keyboard and mouse. To make 3D modeling possible with mouse and keyboard, many 3D interactions, such as point placement or translations of geometry, had to be mapped to the 2D parameter space of the mouse, possibly supported by mouse buttons or keyboard keys. We hypothesize that had the designers of these existing systems had been able to assume immersive virtual reality systems as their target platforms, they would have been able to design 3D interactions much more intuitively. In collaboration with professional architects, we created a simple, but complete 3D modeling tool for virtual environments from the ground up and use direct 3D interaction wherever possible and adequate. In this publication, we present our approaches for interactions for typical 3D modeling functions, such as geometry creation, modification of existing geometry, and assignment of surface materials. We also discuss preliminary user experiences with this system.

The Virtual Museum of Minerals and Molecules: Molecular Visualization in a Virtual Hands-On Museum

ERIC Educational Resources Information Center

Barak, Phillip; Nater, Edward A.

2005-01-01

The Virtual Museum of Minerals and Molecules (VMMM) is a web-based resource presenting interactive, 3-D, research-grade molecular models of more than 150 minerals and molecules of interest to chemical, earth, plant, and environmental sciences. User interactivity with the 3-D display allows models to be rotated, zoomed, and specific regions of…

Game-Like Language Learning in 3-D Virtual Environments

ERIC Educational Resources Information Center

Berns, Anke; Gonzalez-Pardo, Antonio; Camacho, David

2013-01-01

This paper presents our recent experiences with the design of game-like applications in 3-D virtual environments as well as its impact on student motivation and learning. Therefore our paper starts with a brief analysis of the motivational aspects of videogames and virtual worlds (VWs). We then go on to explore the possible benefits of both in the…

Application of 3d Model of Cultural Relics in Virtual Restoration

NASA Astrophysics Data System (ADS)

Zhao, S.; Hou, M.; Hu, Y.; Zhao, Q.

2018-04-01

In the traditional cultural relics splicing process, in order to identify the correct spatial location of the cultural relics debris, experts need to manually splice the existing debris. The repeated contact between debris can easily cause secondary damage to the cultural relics. In this paper, the application process of 3D model of cultural relic in virtual restoration is put forward, and the relevant processes and ideas are verified with the example of Terracotta Warriors data. Through the combination of traditional cultural relics restoration methods and computer virtual reality technology, virtual restoration of high-precision 3D models of cultural relics can provide a scientific reference for virtual restoration, avoiding the secondary damage to the cultural relics caused by improper restoration. The efficiency and safety of the preservation and restoration of cultural relics have been improved.

Intelligent web agents for a 3D virtual community

NASA Astrophysics Data System (ADS)

Dave, T. M.; Zhang, Yanqing; Owen, G. S. S.; Sunderraman, Rajshekhar

2003-08-01

In this paper, we propose an Avatar-based intelligent agent technique for 3D Web based Virtual Communities based on distributed artificial intelligence, intelligent agent techniques, and databases and knowledge bases in a digital library. One of the goals of this joint NSF (IIS-9980130) and ACM SIGGRAPH Education Committee (ASEC) project is to create a virtual community of educators and students who have a common interest in comptuer graphics, visualization, and interactive techniqeus. In this virtual community (ASEC World) Avatars will represent the educators, students, and other visitors to the world. Intelligent agents represented as specially dressed Avatars will be available to assist the visitors to ASEC World. The basic Web client-server architecture of the intelligent knowledge-based avatars is given. Importantly, the intelligent Web agent software system for the 3D virtual community is implemented successfully.

ESL Teacher Training in 3D Virtual Worlds

ERIC Educational Resources Information Center

Kozlova, Iryna; Priven, Dmitri

2015-01-01

Although language learning in 3D Virtual Worlds (VWs) has become a focus of recent research, little is known about the knowledge and skills teachers need to acquire to provide effective task-based instruction in 3D VWs and the type of teacher training that best prepares instructors for such an endeavor. This study employs a situated learning…

Educational Visualizations in 3D Collaborative Virtual Environments: A Methodology

ERIC Educational Resources Information Center

Fominykh, Mikhail; Prasolova-Forland, Ekaterina

2012-01-01

Purpose: Collaborative virtual environments (CVEs) have become increasingly popular in educational settings and the role of 3D content is becoming more and more important. Still, there are many challenges in this area, such as lack of empirical studies that provide design for educational activities in 3D CVEs and lack of norms of how to support…

Evaluation of the performance of 3D virtual screening protocols: RMSD comparisons, enrichment assessments, and decoy selection--what can we learn from earlier mistakes?

PubMed

Kirchmair, Johannes; Markt, Patrick; Distinto, Simona; Wolber, Gerhard; Langer, Thierry

2008-01-01

Within the last few years a considerable amount of evaluative studies has been published that investigate the performance of 3D virtual screening approaches. Thereby, in particular assessments of protein-ligand docking are facing remarkable interest in the scientific community. However, comparing virtual screening approaches is a non-trivial task. Several publications, especially in the field of molecular docking, suffer from shortcomings that are likely to affect the significance of the results considerably. These quality issues often arise from poor study design, biasing, by using improper or inexpressive enrichment descriptors, and from errors in interpretation of the data output. In this review we analyze recent literature evaluating 3D virtual screening methods, with focus on molecular docking. We highlight problematic issues and provide guidelines on how to improve the quality of computational studies. Since 3D virtual screening protocols are in general assessed by their ability to discriminate between active and inactive compounds, we summarize the impact of the composition and preparation of test sets on the outcome of evaluations. Moreover, we investigate the significance of both classic enrichment parameters and advanced descriptors for the performance of 3D virtual screening methods. Furthermore, we review the significance and suitability of RMSD as a measure for the accuracy of protein-ligand docking algorithms and of conformational space sub sampling algorithms.

Distributed Drug Discovery, Part 2: Global Rehearsal of Alkylating Agents for the Synthesis of Resin-Bound Unnatural Amino Acids and Virtual D3 Catalog Construction

PubMed Central

2008-01-01

Distributed Drug Discovery (D3) proposes solving large drug discovery problems by breaking them into smaller units for processing at multiple sites. A key component of the synthetic and computational stages of D3 is the global rehearsal of prospective reagents and their subsequent use in the creation of virtual catalogs of molecules accessible by simple, inexpensive combinatorial chemistry. The first section of this article documents the feasibility of the synthetic component of Distributed Drug Discovery. Twenty-four alkylating agents were rehearsed in the United States, Poland, Russia, and Spain, for their utility in the synthesis of resin-bound unnatural amino acids 1, key intermediates in many combinatorial chemistry procedures. This global reagent rehearsal, coupled to virtual library generation, increases the likelihood that any member of that virtual library can be made. It facilitates the realistic integration of worldwide virtual D3 catalog computational analysis with synthesis. The second part of this article describes the creation of the first virtual D3 catalog. It reports the enumeration of 24 416 acylated unnatural amino acids 5, assembled from lists of either rehearsed or well-precedented alkylating and acylating reagents, and describes how the resulting catalog can be freely accessed, searched, and downloaded by the scientific community. PMID:19105725

Virtual Reality Visualization of Permafrost Dynamics Along a Transect Through Northern Alaska

NASA Astrophysics Data System (ADS)

Chappell, G. G.; Brody, B.; Webb, P.; Chord, J.; Romanovsky, V.; Tipenko, G.

2004-12-01

Understanding permafrost dynamics poses a significant challenge for researchers and planners. Our project uses nontraditional visualization tools to create a 3-D interactive virtual-reality environment in which permafrost dynamics can be explored and experimented with. We have incorporated a numerical soil temperature model by Gennadiy Tipenko and Vladimir Romanovsky of the Geophysical institute at the University of Alaska Fairbanks into an animated tour in space and time in the virtual reality facility of the Arctic Region Supercomputing Center at the University of Alaska Fairbanks. The software is being written by undergraduate interns Patrick Webb and Jordanna Chord under the direction of Professors Chappell and Brody. When using our software, the user appears to be surrounded by a 3-D computer-generated model of the state of Alaska. The eastern portion of the state is displaced upward from the western portion. The data are represented on an animated vertical strip running between the two parts, as if eastern Alaska were raised up, and the soil at the cut could be viewed. We use coloring to highlight significant properties and features of the soil: temperature, the active layer, etc. The user can view data from various parts of the state simply by walking to the appropriate location in the model, or by using a flying-style interface to cover longer distances. Using a control panel, the user can also alter the time, viewing the data for a particular date, or watching the data change with time: a high-speed movie in which long-term changes in permafrost are readily apparent. In the second phase of the project, we connect the visualization directly to the model, running in real time. We allow the user to manipulate the input data and get immediate visual feedback. For example, the user might specify the kind and placement of ground cover, by ``painting'' snowpack, plant species, or fire damage, and be able to see the effect on permafrost stability with no significant time lag.

Dynamic shared state maintenance in distributed virtual environments

NASA Astrophysics Data System (ADS)

Hamza-Lup, Felix George

Advances in computer networks and rendering systems facilitate the creation of distributed collaborative environments in which the distribution of information at remote locations allows efficient communication. Particularly challenging are distributed interactive Virtual Environments (VE) that allow knowledge sharing through 3D information. The purpose of this work is to address the problem of latency in distributed interactive VE and to develop a conceptual model for consistency maintenance in these environments based on the participant interaction model. An area that needs to be explored is the relationship between the dynamic shared state and the interaction with the virtual entities present in the shared scene. Mixed Reality (MR) and VR environments must bring the human participant interaction into the loop through a wide range of electronic motion sensors, and haptic devices. Part of the work presented here defines a novel criterion for categorization of distributed interactive VE and introduces, as well as analyzes, an adaptive synchronization algorithm for consistency maintenance in such environments. As part of the work, a distributed interactive Augmented Reality (AR) testbed and the algorithm implementation details are presented. Currently the testbed is part of several research efforts at the Optical Diagnostics and Applications Laboratory including 3D visualization applications using custom built head-mounted displays (HMDs) with optical motion tracking and a medical training prototype for endotracheal intubation and medical prognostics. An objective method using quaternion calculus is applied for the algorithm assessment. In spite of significant network latency, results show that the dynamic shared state can be maintained consistent at multiple remotely located sites. In further consideration of the latency problems and in the light of the current trends in interactive distributed VE applications, we propose a hybrid distributed system architecture for sensor-based distributed VE that has the potential to improve the system real-time behavior and scalability. (Abstract shortened by UMI.)

3D virtual character reconstruction from projections: a NURBS-based approach

NASA Astrophysics Data System (ADS)

Triki, Olfa; Zaharia, Titus B.; Preteux, Francoise J.

2004-05-01

This work has been carried out within the framework of the industrial project, so-called TOON, supported by the French government. TOON aims at developing tools for automating the traditional 2D cartoon content production. This paper presents preliminary results of the TOON platform. The proposed methodology concerns the issues of 2D/3D reconstruction from a limited number of drawn projections, and 2D/3D manipulation/deformation/refinement of virtual characters. Specifically, we show that the NURBS-based modeling approach developed here offers a well-suited framework for generating deformable 3D virtual characters from incomplete 2D information. Furthermore, crucial functionalities such as animation and non-rigid deformation can be also efficiently handled and solved. Note that user interaction is enabled exclusively in 2D by achieving a multiview constraint specification method. This is fully consistent and compliant with the cartoon creator traditional practice and makes it possible to avoid the use of 3D modeling software packages which are generally complex to manipulate.

Binding Energy Calculation of Patchouli Alcohol Isomer Cyclooxygenase Complexes Suggested as COX-1/COX-2 Selective Inhibitor

PubMed Central

Mahdi, Chanif; Nurdiana, Nurdiana; Kikuchi, Takheshi; Fatchiyah, Fatchiyah

2014-01-01

To understand the structural features that dictate the selectivity of the two isoforms of the prostaglandin H2 synthase (PGHS/COX), the three-dimensional (3D) structure of COX-1/COX-2 was assessed by means of binding energy calculation of virtual molecular dynamic with using ligand alpha-Patchouli alcohol isomers. Molecular interaction studies with COX-1 and COX-2 were done using the molecular docking tools by Hex 8.0. Interactions were further visualized by using Discovery Studio Client 3.5 software tool. The binding energy of molecular interaction was calculated by AMBER12 and Virtual Molecular Dynamic 1.9.1 software. The analysis of the alpha-Patchouli alcohol isomer compounds showed that all alpha-Patchouli alcohol isomers were suggested as inhibitor of COX-1 and COX-2. Collectively, the scoring binding energy calculation (with PBSA Model Solvent) of alpha-Patchouli alcohol isomer compounds (CID442384, CID6432585, CID3080622, CID10955174, and CID56928117) was suggested as candidate for a selective COX-1 inhibitor and CID521903 as nonselective COX-1/COX-2. PMID:25484897

Three-dimensional compound comparison methods and their application in drug discovery.

PubMed

Shin, Woong-Hee; Zhu, Xiaolei; Bures, Mark Gregory; Kihara, Daisuke

2015-07-16

Virtual screening has been widely used in the drug discovery process. Ligand-based virtual screening (LBVS) methods compare a library of compounds with a known active ligand. Two notable advantages of LBVS methods are that they do not require structural information of a target receptor and that they are faster than structure-based methods. LBVS methods can be classified based on the complexity of ligand structure information utilized: one-dimensional (1D), two-dimensional (2D), and three-dimensional (3D). Unlike 1D and 2D methods, 3D methods can have enhanced performance since they treat the conformational flexibility of compounds. In this paper, a number of 3D methods will be reviewed. In addition, four representative 3D methods were benchmarked to understand their performance in virtual screening. Specifically, we tested overall performance in key aspects including the ability to find dissimilar active compounds, and computational speed.

Embodied collaboration support system for 3D shape evaluation in virtual space

NASA Astrophysics Data System (ADS)

Okubo, Masashi; Watanabe, Tomio

2005-12-01

Collaboration mainly consists of two tasks; one is each partner's task that is performed by the individual, the other is communication with each other. Both of them are very important objectives for all the collaboration support system. In this paper, a collaboration support system for 3D shape evaluation in virtual space is proposed on the basis of both studies in 3D shape evaluation and communication support in virtual space. The proposed system provides the two viewpoints for each task. One is the viewpoint of back side of user's own avatar for the smooth communication. The other is that of avatar's eye for 3D shape evaluation. Switching the viewpoints satisfies the task conditions for 3D shape evaluation and communication. The system basically consists of PC, HMD and magnetic sensors, and users can share the embodied interaction by observing interaction between their avatars in virtual space. However, the HMD and magnetic sensors, which are put on the users, would restrict the nonverbal communication. Then, we have tried to compensate the loss of nodding of partner's avatar by introducing the speech-driven embodied interactive actor InterActor. Sensory evaluation by paired comparison of 3D shapes in the collaborative situation in virtual space and in real space and the questionnaire are performed. The result demonstrates the effectiveness of InterActor's nodding in the collaborative situation.

Discovery of new GSK-3β inhibitors through structure-based virtual screening.

PubMed

Dou, Xiaodong; Jiang, Lan; Wang, Yanxing; Jin, Hongwei; Liu, Zhenming; Zhang, Liangren

2018-01-15

Glycogen synthase kinase-3β (GSK-3β) is an attractive therapeutic target for human diseases, such as diabetes, cancer, neurodegenerative diseases, and inflammation. Thus, structure-based virtual screening was performed to identify novel scaffolds of GSK-3β inhibitors, and we observed that conserved water molecules of GSK-3β were suitable for virtual screening. We found 14 hits and D1 (IC 50 of 0.71 μM) were identified. Furthermore, the neuroprotection activity of D1-D3 was validated on a cellular level. 2D similarity searches were used to find derivatives of high inhibitory compounds and an enriched structure-activity relationship suggested that these skeletons were worthy of study as potent GSK-3β inhibitors. Copyright © 2017. Published by Elsevier Ltd.

Valorisation of Cultural Heritage Through Virtual Visit and Augmented Reality: the Case of the Abbey of Epau (france)

NASA Astrophysics Data System (ADS)

Simonetto, E.; Froment, C.; Labergerie, E.; Ferré, G.; Séchet, B.; Chédorge, H.; Cali, J.; Polidori, L.

2013-07-01

Terrestrial Laser Scanning (TLS), 3-D modeling and its Web visualization are the three key steps needed to perform storage and grant-free and wide access to cultural heritage, as highlighted in many recent examples. The goal of this study is to set up 3-D Web resources for "virtually" visiting the exterior of the Abbaye de l'Epau, an old French abbey which has both a rich history and delicate architecture. The virtuality is considered in two ways: the flowing navigation in a virtual reality environment around the abbey and a game activity using augmented reality. First of all, the data acquisition consists in GPS and tacheometry survey, terrestrial laser scanning and photography acquisition. After data pre-processing, the meshed and textured 3-D model is generated using 3-D Reshaper commercial software. The virtual reality visit and augmented reality animation are then created using Unity software. This work shows the interest of such tools in bringing out the regional cultural heritage and making it attractive to the public.

Application of advanced virtual reality and 3D computer assisted technologies in tele-3D-computer assisted surgery in rhinology.

PubMed

Klapan, Ivica; Vranjes, Zeljko; Prgomet, Drago; Lukinović, Juraj

2008-03-01

The real-time requirement means that the simulation should be able to follow the actions of the user that may be moving in the virtual environment. The computer system should also store in its memory a three-dimensional (3D) model of the virtual environment. In that case a real-time virtual reality system will update the 3D graphic visualization as the user moves, so that up-to-date visualization is always shown on the computer screen. Upon completion of the tele-operation, the surgeon compares the preoperative and postoperative images and models of the operative field, and studies video records of the procedure itself Using intraoperative records, animated images of the real tele-procedure performed can be designed. Virtual surgery offers the possibility of preoperative planning in rhinology. The intraoperative use of computer in real time requires development of appropriate hardware and software to connect medical instrumentarium with the computer and to operate the computer by thus connected instrumentarium and sophisticated multimedia interfaces.

Reduced Mental Load in Learning a Motor Visual Task with Virtual 3D Method

ERIC Educational Resources Information Center

Dan, A.; Reiner, M.

2018-01-01

Distance learning is expanding rapidly, fueled by the novel technologies for shared recorded teaching sessions on the Web. Here, we ask whether 3D stereoscopic (3DS) virtual learning environment teaching sessions are more compelling than typical two-dimensional (2D) video sessions and whether this type of teaching results in superior learning. The…

Employing Virtual Humans for Education and Training in X3D/VRML Worlds

ERIC Educational Resources Information Center

Ieronutti, Lucio; Chittaro, Luca

2007-01-01

Web-based education and training provides a new paradigm for imparting knowledge; students can access the learning material anytime by operating remotely from any location. Web3D open standards, such as X3D and VRML, support Web-based delivery of Educational Virtual Environments (EVEs). EVEs have a great potential for learning and training…

Design of Learning Spaces in 3D Virtual Worlds: An Empirical Investigation of "Second Life"

ERIC Educational Resources Information Center

Minocha, Shailey; Reeves, Ahmad John

2010-01-01

"Second Life" (SL) is a three-dimensional (3D) virtual world, and educational institutions are adopting SL to support their teaching and learning. Although the question of how 3D learning spaces should be designed to support student learning and engagement has been raised among SL educators and designers, there is hardly any guidance or…

Virtual surgical planning and 3D printing in prosthetic orbital reconstruction with percutaneous implants: a technical case report

PubMed Central

Huang, Yu-Hui; Seelaus, Rosemary; Zhao, Linping; Patel, Pravin K; Cohen, Mimis

2016-01-01

Osseointegrated titanium implants to the cranial skeleton for retention of facial prostheses have proven to be a reliable replacement for adhesive systems. However, improper placement of the implants can jeopardize prosthetic outcomes, and long-term success of an implant-retained prosthesis. Three-dimensional (3D) computer imaging, virtual planning, and 3D printing have become accepted components of the preoperative planning and design phase of treatment. Computer-aided design and computer-assisted manufacture that employ cone-beam computed tomography data offer benefits to patient treatment by contributing to greater predictability and improved treatment efficiencies with more reliable outcomes in surgical and prosthetic reconstruction. 3D printing enables transfer of the virtual surgical plan to the operating room by fabrication of surgical guides. Previous studies have shown that accuracy improves considerably with guided implantation when compared to conventional template or freehand implant placement. This clinical case report demonstrates the use of a 3D technological pathway for preoperative virtual planning through prosthesis fabrication, utilizing 3D printing, for a patient with an acquired orbital defect that was restored with an implant-retained silicone orbital prosthesis. PMID:27843356

Virtual surgical planning and 3D printing in prosthetic orbital reconstruction with percutaneous implants: a technical case report.

PubMed

Huang, Yu-Hui; Seelaus, Rosemary; Zhao, Linping; Patel, Pravin K; Cohen, Mimis

2016-01-01

Osseointegrated titanium implants to the cranial skeleton for retention of facial prostheses have proven to be a reliable replacement for adhesive systems. However, improper placement of the implants can jeopardize prosthetic outcomes, and long-term success of an implant-retained prosthesis. Three-dimensional (3D) computer imaging, virtual planning, and 3D printing have become accepted components of the preoperative planning and design phase of treatment. Computer-aided design and computer-assisted manufacture that employ cone-beam computed tomography data offer benefits to patient treatment by contributing to greater predictability and improved treatment efficiencies with more reliable outcomes in surgical and prosthetic reconstruction. 3D printing enables transfer of the virtual surgical plan to the operating room by fabrication of surgical guides. Previous studies have shown that accuracy improves considerably with guided implantation when compared to conventional template or freehand implant placement. This clinical case report demonstrates the use of a 3D technological pathway for preoperative virtual planning through prosthesis fabrication, utilizing 3D printing, for a patient with an acquired orbital defect that was restored with an implant-retained silicone orbital prosthesis.

2D and 3D Traveling Salesman Problem

ERIC Educational Resources Information Center

Haxhimusa, Yll; Carpenter, Edward; Catrambone, Joseph; Foldes, David; Stefanov, Emil; Arns, Laura; Pizlo, Zygmunt

2011-01-01

When a two-dimensional (2D) traveling salesman problem (TSP) is presented on a computer screen, human subjects can produce near-optimal tours in linear time. In this study we tested human performance on a real and virtual floor, as well as in a three-dimensional (3D) virtual space. Human performance on the real floor is as good as that on a…

Research on virtual Guzheng based on Kinect

NASA Astrophysics Data System (ADS)

Li, Shuyao; Xu, Kuangyi; Zhang, Heng

2018-05-01

There are a lot of researches on virtual instruments, but there are few on classical Chinese instruments, and the techniques used are very limited. This paper uses Unity 3D and Kinect camera combined with virtual reality technology and gesture recognition method to design a virtual playing system of Guzheng, a traditional Chinese musical instrument, with demonstration function. In this paper, the real scene obtained by Kinect camera is fused with virtual Guzheng in Unity 3D. The depth data obtained by Kinect and the Suzuki85 algorithm are used to recognize the relative position of the user's right hand and the virtual Guzheng, and the hand gesture of the user is recognized by Kinect.

Facilitating 3D Virtual World Learning Environments Creation by Non-Technical End Users through Template-Based Virtual World Instantiation

ERIC Educational Resources Information Center

Liu, Chang; Zhong, Ying; Ozercan, Sertac; Zhu, Qing

2013-01-01

This paper presents a template-based solution to overcome technical barriers non-technical computer end users face when developing functional learning environments in three-dimensional virtual worlds (3DVW). "iVirtualWorld," a prototype of a platform-independent 3DVW creation tool that implements the proposed solution, facilitates 3DVW…

[Fabrication and accuracy research on 3D printing dental model based on cone beam computed tomography digital modeling].

PubMed

Zhang, Hui-Rong; Yin, Le-Feng; Liu, Yan-Li; Yan, Li-Yi; Wang, Ning; Liu, Gang; An, Xiao-Li; Liu, Bin

2018-04-01

The aim of this study is to build a digital dental model with cone beam computed tomography (CBCT), to fabricate a virtual model via 3D printing, and to determine the accuracy of 3D printing dental model by comparing the result with a traditional dental cast. CBCT of orthodontic patients was obtained to build a digital dental model by using Mimics 10.01 and Geomagic studio software. The 3D virtual models were fabricated via fused deposition modeling technique (FDM). The 3D virtual models were compared with the traditional cast models by using a Vernier caliper. The measurements used for comparison included the width of each tooth, the length and width of the maxillary and mandibular arches, and the length of the posterior dental crest. 3D printing models had higher accuracy compared with the traditional cast models. The results of the paired t-test of all data showed that no statistically significant difference was observed between the two groups (P>0.05). Dental digital models built with CBCT realize the digital storage of patients' dental condition. The virtual dental model fabricated via 3D printing avoids traditional impression and simplifies the clinical examination process. The 3D printing dental models produced via FDM show a high degree of accuracy. Thus, these models are appropriate for clinical practice.

A collaborative virtual reality environment for neurosurgical planning and training.

PubMed

Kockro, Ralf A; Stadie, Axel; Schwandt, Eike; Reisch, Robert; Charalampaki, Cleopatra; Ng, Ivan; Yeo, Tseng Tsai; Hwang, Peter; Serra, Luis; Perneczky, Axel

2007-11-01

We have developed a highly interactive virtual environment that enables collaborative examination of stereoscopic three-dimensional (3-D) medical imaging data for planning, discussing, or teaching neurosurgical approaches and strategies. The system consists of an interactive console with which the user manipulates 3-D data using hand-held and tracked devices within a 3-D virtual workspace and a stereoscopic projection system. The projection system displays the 3-D data on a large screen while the user is working with it. This setup allows users to interact intuitively with complex 3-D data while sharing this information with a larger audience. We have been using this system on a routine clinical basis and during neurosurgical training courses to collaboratively plan and discuss neurosurgical procedures with 3-D reconstructions of patient-specific magnetic resonance and computed tomographic imaging data or with a virtual model of the temporal bone. Working collaboratively with the 3-D information of a large, interactive, stereoscopic projection provides an unambiguous way to analyze and understand the anatomic spatial relationships of different surgical corridors. In our experience, the system creates a unique forum for open and precise discussion of neurosurgical approaches. We believe the system provides a highly effective way to work with 3-D data in a group, and it significantly enhances teaching of neurosurgical anatomy and operative strategies.

Computer-Aided Drug Design in Epigenetics

NASA Astrophysics Data System (ADS)

Lu, Wenchao; Zhang, Rukang; Jiang, Hao; Zhang, Huimin; Luo, Cheng

2018-03-01

Epigenetic dysfunction has been widely implicated in several diseases especially cancers thus highlights the therapeutic potential for chemical interventions in this field. With rapid development of computational methodologies and high-performance computational resources, computer-aided drug design has emerged as a promising strategy to speed up epigenetic drug discovery. Herein, we make a brief overview of major computational methods reported in the literature including druggability prediction, virtual screening, homology modeling, scaffold hopping, pharmacophore modeling, molecular dynamics simulations, quantum chemistry calculation and 3D quantitative structure activity relationship that have been successfully applied in the design and discovery of epi-drugs and epi-probes. Finally, we discuss about major limitations of current virtual drug design strategies in epigenetics drug discovery and future directions in this field.

Computer-Aided Drug Design in Epigenetics

PubMed Central

Lu, Wenchao; Zhang, Rukang; Jiang, Hao; Zhang, Huimin; Luo, Cheng

2018-01-01

Epigenetic dysfunction has been widely implicated in several diseases especially cancers thus highlights the therapeutic potential for chemical interventions in this field. With rapid development of computational methodologies and high-performance computational resources, computer-aided drug design has emerged as a promising strategy to speed up epigenetic drug discovery. Herein, we make a brief overview of major computational methods reported in the literature including druggability prediction, virtual screening, homology modeling, scaffold hopping, pharmacophore modeling, molecular dynamics simulations, quantum chemistry calculation, and 3D quantitative structure activity relationship that have been successfully applied in the design and discovery of epi-drugs and epi-probes. Finally, we discuss about major limitations of current virtual drug design strategies in epigenetics drug discovery and future directions in this field. PMID:29594101

3D Surgical Simulation

PubMed Central

Cevidanes, Lucia; Tucker, Scott; Styner, Martin; Kim, Hyungmin; Chapuis, Jonas; Reyes, Mauricio; Proffit, William; Turvey, Timothy; Jaskolka, Michael

2009-01-01

This paper discusses the development of methods for computer-aided jaw surgery. Computer-aided jaw surgery allows us to incorporate the high level of precision necessary for transferring virtual plans into the operating room. We also present a complete computer-aided surgery (CAS) system developed in close collaboration with surgeons. Surgery planning and simulation include construction of 3D surface models from Cone-beam CT (CBCT), dynamic cephalometry, semi-automatic mirroring, interactive cutting of bone and bony segment repositioning. A virtual setup can be used to manufacture positioning splints for intra-operative guidance. The system provides further intra-operative assistance with the help of a computer display showing jaw positions and 3D positioning guides updated in real-time during the surgical procedure. The CAS system aids in dealing with complex cases with benefits for the patient, with surgical practice, and for orthodontic finishing. Advanced software tools for diagnosis and treatment planning allow preparation of detailed operative plans, osteotomy repositioning, bone reconstructions, surgical resident training and assessing the difficulties of the surgical procedures prior to the surgery. CAS has the potential to make the elaboration of the surgical plan a more flexible process, increase the level of detail and accuracy of the plan, yield higher operative precision and control, and enhance documentation of cases. Supported by NIDCR DE017727, and DE018962 PMID:20816308

3D virtual human atria: A computational platform for studying clinical atrial fibrillation.

PubMed

Aslanidi, Oleg V; Colman, Michael A; Stott, Jonathan; Dobrzynski, Halina; Boyett, Mark R; Holden, Arun V; Zhang, Henggui

2011-10-01

Despite a vast amount of experimental and clinical data on the underlying ionic, cellular and tissue substrates, the mechanisms of common atrial arrhythmias (such as atrial fibrillation, AF) arising from the functional interactions at the whole atria level remain unclear. Computational modelling provides a quantitative framework for integrating such multi-scale data and understanding the arrhythmogenic behaviour that emerges from the collective spatio-temporal dynamics in all parts of the heart. In this study, we have developed a multi-scale hierarchy of biophysically detailed computational models for the human atria--the 3D virtual human atria. Primarily, diffusion tensor MRI reconstruction of the tissue geometry and fibre orientation in the human sinoatrial node (SAN) and surrounding atrial muscle was integrated into the 3D model of the whole atria dissected from the Visible Human dataset. The anatomical models were combined with the heterogeneous atrial action potential (AP) models, and used to simulate the AP conduction in the human atria under various conditions: SAN pacemaking and atrial activation in the normal rhythm, break-down of regular AP wave-fronts during rapid atrial pacing, and the genesis of multiple re-entrant wavelets characteristic of AF. Contributions of different properties of the tissue to mechanisms of the normal rhythm and arrhythmogenesis were investigated. Primarily, the simulations showed that tissue heterogeneity caused the break-down of the normal AP wave-fronts at rapid pacing rates, which initiated a pair of re-entrant spiral waves; and tissue anisotropy resulted in a further break-down of the spiral waves into multiple meandering wavelets characteristic of AF. The 3D virtual atria model itself was incorporated into the torso model to simulate the body surface ECG patterns in the normal and arrhythmic conditions. Therefore, a state-of-the-art computational platform has been developed, which can be used for studying multi-scale electrical phenomena during atrial conduction and AF arrhythmogenesis. Results of such simulations can be directly compared with electrophysiological and endocardial mapping data, as well as clinical ECG recordings. The virtual human atria can provide in-depth insights into 3D excitation propagation processes within atrial walls of a whole heart in vivo, which is beyond the current technical capabilities of experimental or clinical set-ups. Copyright © 2011 Elsevier Ltd. All rights reserved.

Mobile viewer system for virtual 3D space using infrared LED point markers and camera

NASA Astrophysics Data System (ADS)

Sakamoto, Kunio; Taneji, Shoto

2006-09-01

The authors have developed a 3D workspace system using collaborative imaging devices. A stereoscopic display enables this system to project 3D information. In this paper, we describe the position detecting system for a see-through 3D viewer. A 3D display system is useful technology for virtual reality, mixed reality and augmented reality. We have researched spatial imaging and interaction system. We have ever proposed 3D displays using the slit as a parallax barrier, the lenticular screen and the holographic optical elements(HOEs) for displaying active image 1)2)3)4). The purpose of this paper is to propose the interactive system using these 3D imaging technologies. The observer can view virtual images in the real world when the user watches the screen of a see-through 3D viewer. The goal of our research is to build the display system as follows; when users see the real world through the mobile viewer, the display system gives users virtual 3D images, which is floating in the air, and the observers can touch these floating images and interact them such that kids can make play clay. The key technologies of this system are the position recognition system and the spatial imaging display. The 3D images are presented by the improved parallax barrier 3D display. Here the authors discuss the measuring method of the mobile viewer using infrared LED point markers and a camera in the 3D workspace (augmented reality world). The authors show the geometric analysis of the proposed measuring method, which is the simplest method using a single camera not the stereo camera, and the results of our viewer system.

A Novel Method of Orbital Floor Reconstruction Using Virtual Planning, 3-Dimensional Printing, and Autologous Bone.

PubMed

Vehmeijer, Maarten; van Eijnatten, Maureen; Liberton, Niels; Wolff, Jan

2016-08-01

Fractures of the orbital floor are often a result of traffic accidents or interpersonal violence. To date, numerous materials and methods have been used to reconstruct the orbital floor. However, simple and cost-effective 3-dimensional (3D) printing technologies for the treatment of orbital floor fractures are still sought. This study describes a simple, precise, cost-effective method of treating orbital fractures using 3D printing technologies in combination with autologous bone. Enophthalmos and diplopia developed in a 64-year-old female patient with an orbital floor fracture. A virtual 3D model of the fracture site was generated from computed tomography images of the patient. The fracture was virtually closed using spline interpolation. Furthermore, a virtual individualized mold of the defect site was created, which was manufactured using an inkjet printer. The tangible mold was subsequently used during surgery to sculpture an individualized autologous orbital floor implant. Virtual reconstruction of the orbital floor and the resulting mold enhanced the overall accuracy and efficiency of the surgical procedure. The sculptured autologous orbital floor implant showed an excellent fit in vivo. The combination of virtual planning and 3D printing offers an accurate and cost-effective treatment method for orbital floor fractures. Copyright © 2016 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Effects of 3D Virtual Simulators in the Introductory Wind Energy Course: A Tool for Teaching Engineering Concepts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Do, Phuong T.; Moreland, John R.; Delgado, Catherine

Our research provides an innovative solution for optimizing learning effectiveness and improving postsecondary education through the development of virtual simulators that can be easily used and integrated into existing wind energy curriculum. Two 3D virtual simulators are developed in our laboratory for use in an immersive 3D virtual reality (VR) system or for 3D display on a 2D screen. Our goal is to apply these prototypical simulators to train postsecondary students and professionals in wind energy education; and to offer experiential learning opportunities in 3D modeling, simulation, and visualization. The issue of transferring learned concepts to practical applications is amore » widespread problem in postsecondary education. Related to this issue is a critical demand to educate and train a generation of professionals for the wind energy industry. With initiatives such as the U.S. Department of Energy's “20% Wind Energy by 2030” outlining an exponential increase of wind energy capacity over the coming years, revolutionary educational reform is needed to meet the demand for education in the field of wind energy. These developments and implementation of Virtual Simulators and accompanying curriculum will propel national reforms, meeting the needs of the wind energy industrial movement and addressing broader educational issues that affect a number of disciplines.« less

Effects of 3D Virtual Simulators in the Introductory Wind Energy Course: A Tool for Teaching Engineering Concepts

DOE PAGES

Do, Phuong T.; Moreland, John R.; Delgado, Catherine; ...

2013-01-01

Our research provides an innovative solution for optimizing learning effectiveness and improving postsecondary education through the development of virtual simulators that can be easily used and integrated into existing wind energy curriculum. Two 3D virtual simulators are developed in our laboratory for use in an immersive 3D virtual reality (VR) system or for 3D display on a 2D screen. Our goal is to apply these prototypical simulators to train postsecondary students and professionals in wind energy education; and to offer experiential learning opportunities in 3D modeling, simulation, and visualization. The issue of transferring learned concepts to practical applications is amore » widespread problem in postsecondary education. Related to this issue is a critical demand to educate and train a generation of professionals for the wind energy industry. With initiatives such as the U.S. Department of Energy's “20% Wind Energy by 2030” outlining an exponential increase of wind energy capacity over the coming years, revolutionary educational reform is needed to meet the demand for education in the field of wind energy. These developments and implementation of Virtual Simulators and accompanying curriculum will propel national reforms, meeting the needs of the wind energy industrial movement and addressing broader educational issues that affect a number of disciplines.« less

Development of a Virtual Museum Including a 4d Presentation of Building History in Virtual Reality

NASA Astrophysics Data System (ADS)

Kersten, T. P.; Tschirschwitz, F.; Deggim, S.

2017-02-01

In the last two decades the definition of the term "virtual museum" changed due to rapid technological developments. Using today's available 3D technologies a virtual museum is no longer just a presentation of collections on the Internet or a virtual tour of an exhibition using panoramic photography. On one hand, a virtual museum should enhance a museum visitor's experience by providing access to additional materials for review and knowledge deepening either before or after the real visit. On the other hand, a virtual museum should also be used as teaching material in the context of museum education. The laboratory for Photogrammetry & Laser Scanning of the HafenCity University Hamburg has developed a virtual museum (VM) of the museum "Alt-Segeberger Bürgerhaus", a historic town house. The VM offers two options for visitors wishing to explore the museum without travelling to the city of Bad Segeberg, Schleswig-Holstein, Germany. Option a, an interactive computer-based, tour for visitors to explore the exhibition and to collect information of interest or option b, to immerse into virtual reality in 3D with the HTC Vive Virtual Reality System.

Identification of critical chemical features for Aurora kinase-B inhibitors using Hip-Hop, virtual screening and molecular docking

NASA Astrophysics Data System (ADS)

Sakkiah, Sugunadevi; Thangapandian, Sundarapandian; John, Shalini; Lee, Keun Woo

2011-01-01

This study was performed to find the selective chemical features for Aurora kinase-B inhibitors using the potent methods like Hip-Hop, virtual screening, homology modeling, molecular dynamics and docking. The best hypothesis, Hypo1 was validated toward a wide range of test set containing the selective inhibitors of Aurora kinase-B. Homology modeling and molecular dynamics studies were carried out to perform the molecular docking studies. The best hypothesis Hypo1 was used as a 3D query to screen the chemical databases. The screened molecules from the databases were sorted based on ADME and drug like properties. The selective hit compounds were docked and the hydrogen bond interactions with the critical amino acids present in Aurora kinase-B were compared with the chemical features present in the Hypo1. Finally, we suggest that the chemical features present in the Hypo1 are vital for a molecule to inhibit the Aurora kinase-B activity.

Spatial issues in user interface design from a graphic design perspective

NASA Technical Reports Server (NTRS)

Marcus, Aaron

1989-01-01

The user interface of a computer system is a visual display that provides information about the status of operations on data within the computer and control options to the user that enable adjustments to these operations. From the very beginning of computer technology the user interface was a spatial display, although its spatial features were not necessarily complex or explicitly recognized by the users. All text and nonverbal signs appeared in a virtual space generally thought of as a single flat plane of symbols. Current technology of high performance workstations permits any element of the display to appear as dynamic, multicolor, 3-D signs in a virtual 3-D space. The complexity of appearance and the user's interaction with the display provide significant challenges to the graphic designer of current and future user interfaces. In particular, spatial depiction provides many opportunities for effective communication of objects, structures, processes, navigation, selection, and manipulation. Issues are presented that are relevant to the graphic designer seeking to optimize the user interface's spatial attributes for effective visual communication.

Structure-based virtual screening and characterization of a novel IL-6 antagonistic compound from synthetic compound database.

PubMed

Wang, Jing; Qiao, Chunxia; Xiao, He; Lin, Zhou; Li, Yan; Zhang, Jiyan; Shen, Beifen; Fu, Tinghuan; Feng, Jiannan

2016-01-01

According to the three-dimensional (3D) complex structure of (hIL-6⋅hIL-6R⋅gp 130) 2 and the binding orientation of hIL-6, three compounds with high affinity to hIL-6R and bioactivity to block hIL-6 in vitro were screened theoretically from the chemical databases, including 3D-Available Chemicals Directory (ACD) and MDL Drug Data Report (MDDR), by means of the computer-guided virtual screening method. Using distance geometry, molecular modeling and molecular dynamics trajectory analysis methods, the binding mode and binding energy of the three compounds were evaluated theoretically. Enzyme-linked immunosorbent assay analysis demonstrated that all the three compounds could block IL-6 binding to IL-6R specifically. However, only compound 1 could effectively antagonize the function of hIL-6 and inhibit the proliferation of XG-7 cells in a dose-dependent manner, whereas it showed no cytotoxicity to SP2/0 or L929 cells. These data demonstrated that the compound 1 could be a promising candidate of hIL-6 antagonist.

A virtual reality oriented clinical experiment on post-stroke rehabilitation: performance and preference comparison among different stereoscopic displays­

NASA Astrophysics Data System (ADS)

Yeh, Shih-Ching; Rizzo, Albert; Sawchuk, Alexander A.

2007-02-01

We have developed a novel VR task: the Dynamic Reaching Test, that measures human forearm movement in 3D space. In this task, three different stereoscopic displays: autostereoscopic (AS), shutter glasses (SG) and head mounted display (HMD), are used in tests in which subjects must catch a virtual ball thrown at them. Parameters such as percentage of successful catches, movement efficiency (subject path length compared to minimal path length), and reaction time are measured to evaluate differences in 3D perception among the three stereoscopic displays. The SG produces the highest percentage of successful catches, though the difference between the three displays is small, implying that users can perform the VR task with any of the displays. The SG and HMD produced the best movement efficiency, while the AS was slightly less efficient. Finally, the AS and HMD produced similar reaction times that were slightly higher (by 0.1 s) than the SG. We conclude that SG and HMD displays were the most effective, but only slightly better than the AS display.

Real-Time 3D Visualization

NASA Technical Reports Server (NTRS)

1997-01-01

Butler Hine, former director of the Intelligent Mechanism Group (IMG) at Ames Research Center, and five others partnered to start Fourth Planet, Inc., a visualization company that specializes in the intuitive visual representation of dynamic, real-time data over the Internet and Intranet. Over a five-year period, the then NASA researchers performed ten robotic field missions in harsh climes to mimic the end- to-end operations of automated vehicles trekking across another world under control from Earth. The core software technology for these missions was the Virtual Environment Vehicle Interface (VEVI). Fourth Planet has released VEVI4, the fourth generation of the VEVI software, and NetVision. VEVI4 is a cutting-edge computer graphics simulation and remote control applications tool. The NetVision package allows large companies to view and analyze in virtual 3D space such things as the health or performance of their computer network or locate a trouble spot on an electric power grid. Other products are forthcoming. Fourth Planet is currently part of the NASA/Ames Technology Commercialization Center, a business incubator for start-up companies.

Inspiring Equal Contribution and Opportunity in a 3D Multi-User Virtual Environment: Bringing Together Men Gamers and Women Non-Gamers in Second Life[R

ERIC Educational Resources Information Center

deNoyelles, Aimee; Seo, Kay Kyeong-Ju

2012-01-01

A 3D multi-user virtual environment holds promise to support and enhance student online learning communities due to its ability to promote global synchronous interaction and collaboration, rich multisensory experience and expression, and elaborate design capabilities. Second Life[R], a multi-user virtual environment intended for adult users 18 and…

DOE Office of Scientific and Technical Information (OSTI.GOV)

Markidis, S.; Rizwan, U.

The use of virtual nuclear control room can be an effective and powerful tool for training personnel working in the nuclear power plants. Operators could experience and simulate the functioning of the plant, even in critical situations, without being in a real power plant or running any risk. 3D models can be exported to Virtual Reality formats and then displayed in the Virtual Reality environment providing an immersive 3D experience. However, two major limitations of this approach are that 3D models exhibit static textures, and they are not fully interactive and therefore cannot be used effectively in training personnel. Inmore » this paper we first describe a possible solution for embedding the output of a computer application in a 3D virtual scene, coupling real-world applications and VR systems. The VR system reported here grabs the output of an application running on an X server; creates a texture with the output and then displays it on a screen or a wall in the virtual reality environment. We then propose a simple model for providing interaction between the user in the VR system and the running simulator. This approach is based on the use of internet-based application that can be commanded by a laptop or tablet-pc added to the virtual environment. (authors)« less

A second life for eHealth: prospects for the use of 3-D virtual worlds in clinical psychology.

PubMed

Gorini, Alessandra; Gaggioli, Andrea; Vigna, Cinzia; Riva, Giuseppe

2008-08-05

The aim of the present paper is to describe the role played by three-dimensional (3-D) virtual worlds in eHealth applications, addressing some potential advantages and issues related to the use of this emerging medium in clinical practice. Due to the enormous diffusion of the World Wide Web (WWW), telepsychology, and telehealth in general, have become accepted and validated methods for the treatment of many different health care concerns. The introduction of the Web 2.0 has facilitated the development of new forms of collaborative interaction between multiple users based on 3-D virtual worlds. This paper describes the development and implementation of a form of tailored immersive e-therapy called p-health whose key factor is interreality, that is, the creation of a hybrid augmented experience merging physical and virtual worlds. We suggest that compared with conventional telehealth applications such as emails, chat, and videoconferences, the interaction between real and 3-D virtual worlds may convey greater feelings of presence, facilitate the clinical communication process, positively influence group processes and cohesiveness in group-based therapies, and foster higher levels of interpersonal trust between therapists and patients. However, challenges related to the potentially addictive nature of such virtual worlds and questions related to privacy and personal safety will also be discussed.

Utilising a Collaborative Macro-Script to Enhance Student Engagement: A Mixed Method Study in a 3D Virtual Environment

ERIC Educational Resources Information Center

Bouta, Hara; Retalis, Symeon; Paraskeva, Fotini

2012-01-01

This study examines the effect of using an online 3D virtual environment in teaching Mathematics in Primary Education. In particular, it explores the extent to which student engagement--behavioral, affective and cognitive--is fostered by such tools in order to enhance collaborative learning. For the study we used a purpose-created 3D virtual…

A Proposed Framework for Collaborative Design in a Virtual Environment

NASA Astrophysics Data System (ADS)

Breland, Jason S.; Shiratuddin, Mohd Fairuz

This paper describes a proposed framework for a collaborative design in a virtual environment. The framework consists of components that support a true collaborative design in a real-time 3D virtual environment. In support of the proposed framework, a prototype application is being developed. The authors envision the framework will have, but not limited to the following features: (1) real-time manipulation of 3D objects across the network, (2) support for multi-designer activities and information access, (3) co-existence within same virtual space, etc. This paper also discusses a proposed testing to determine the possible benefits of a collaborative design in a virtual environment over other forms of collaboration, and results from a pilot test.

Development of real-time motion capture system for 3D on-line games linked with virtual character

NASA Astrophysics Data System (ADS)

Kim, Jong Hyeong; Ryu, Young Kee; Cho, Hyung Suck

2004-10-01

Motion tracking method is being issued as essential part of the entertainment, medical, sports, education and industry with the development of 3-D virtual reality. Virtual human character in the digital animation and game application has been controlled by interfacing devices; mouse, joysticks, midi-slider, and so on. Those devices could not enable virtual human character to move smoothly and naturally. Furthermore, high-end human motion capture systems in commercial market are expensive and complicated. In this paper, we proposed a practical and fast motion capturing system consisting of optic sensors, and linked the data with 3-D game character with real time. The prototype experiment setup is successfully applied to a boxing game which requires very fast movement of human character.

Virtual Australia and New Zealand (VANZ): Creating a piece of Digital Earth

NASA Astrophysics Data System (ADS)

Haines, M.

2014-02-01

VANZ is an Initiative of a wide group of research, government, industry, technology and legal stakeholders in Australia and New Zealand. Its purpose is to broker development of the 'Authorised Virtual World' that brings together 3D Spatial and Building Information Modelling within a proposed new Legal Framework. The aim is to create an 'authoritative' and 'enduring' 3D model of both the 'physical attributes', and 'legal entitlements' relating to every property. This 'authorised virtual world' would be used in all 'property-related' activities - to deliver better, quicker and cheaper outcomes. It would also be used as the context for serious games and to model dynamic processes within the built environment, as well as for emergency response and disaster recovery. Productivity savings across Australia have been estimated at 5 billion pa for the design and construct phases alone. The problem for owners, bankers, insurers, architects, engineers and construction companies, and others, is that they require access to 'authoritative' and detailed 3D data for their own purposes, that must also be securely shared with others up and down the 'property' chain, and over time. All parties also need to know what are the rights, responsibilities and restrictions applying to the data, as well as to the land and buildings that it models. VANZ proposes the creation of a network of Data Banks, to hold the 'authoritative data set', 'in perpetuity', along with the associated software and virtual hardware used to model it. Under the proposal, rights of access to the 'authoritative data' will mirror each person's rights in the property that the data models. As more and more buildings are modelled (inside and out), privacy, security and liability become issues of paramount importance. This paper offers a way for the global community to address these issues. It is targeted at all who have an interest in the practical implementation of Digital Earth for the built environment - including new business opportunities worth billions.

Simulation of mirror surfaces for virtual estimation of visibility lines for 3D motor vehicle collision reconstruction.

PubMed

Leipner, Anja; Dobler, Erika; Braun, Marcel; Sieberth, Till; Ebert, Lars

2017-10-01

3D reconstructions of motor vehicle collisions are used to identify the causes of these events and to identify potential violations of traffic regulations. Thus far, the reconstruction of mirrors has been a problem since they are often based on approximations or inaccurate data. Our aim with this paper was to confirm that structured light scans of a mirror improve the accuracy of simulating the field of view of mirrors. We analyzed the performances of virtual mirror surfaces based on structured light scans using real mirror surfaces and their reflections as references. We used an ATOS GOM III scanner to scan the mirrors and processed the 3D data using Geomagic Wrap. For scene reconstruction and to generate virtual images, we used 3ds Max. We compared the simulated virtual images and photographs of real scenes using Adobe Photoshop. Our results showed that we achieved clear and even mirror results and that the mirrors behaved as expected. The greatest measured deviation between an original photo and the corresponding virtual image was 20 pixels in the transverse direction for an image width of 4256 pixels. We discussed the influences of data processing and alignment of the 3D models on the results. The study was limited to a distance of 1.6m, and the method was not able to simulate an interior mirror. In conclusion, structured light scans of mirror surfaces can be used to simulate virtual mirror surfaces with regard to 3D motor vehicle collision reconstruction. Copyright © 2017 Elsevier B.V. All rights reserved.

Algorithms for extraction of structural attitudes from 3D outcrop models

NASA Astrophysics Data System (ADS)

Duelis Viana, Camila; Endlein, Arthur; Ademar da Cruz Campanha, Ginaldo; Henrique Grohmann, Carlos

2016-05-01

The acquisition of geological attitudes on rock cuts using traditional field compass survey can be a time consuming, dangerous, or even impossible task depending on the conditions and location of outcrops. The importance of this type of data in rock-mass classifications and structural geology has led to the development of new techniques, in which the application of photogrammetric 3D digital models has had an increasing use. In this paper we present two algorithms for extraction of attitudes of geological discontinuities from virtual outcrop models: ply2atti and scanline, implemented with the Python programming language. The ply2atti algorithm allows for the virtual sampling of planar discontinuities appearing on the 3D model as individual exposed surfaces, while the scanline algorithm allows the sampling of discontinuities (surfaces and traces) along a virtual scanline. Application to digital models of a simplified test setup and a rock cut demonstrated a good correlation between the surveys undertaken using traditional field compass reading and virtual sampling on 3D digital models.

A 3D visualization and simulation of the individual human jaw.

PubMed

Muftić, Osman; Keros, Jadranka; Baksa, Sarajko; Carek, Vlado; Matković, Ivo

2003-01-01

A new biomechanical three-dimensional (3D) model for the human mandible based on computer-generated virtual model is proposed. Using maps obtained from the special kinds of photos of the face of the real subject, it is possible to attribute personality to the virtual character, while computer animation offers movements and characteristics within the confines of space and time of the virtual world. A simple two-dimensional model of the jaw cannot explain the biomechanics, where the muscular forces through occlusion and condylar surfaces are in the state of 3D equilibrium. In the model all forces are resolved into components according to a selected coordinate system. The muscular forces act on the jaw, along with the necessary force level for chewing as some kind of mandible balance, preventing dislocation and loading of nonarticular tissues. In the work is used new approach to computer-generated animation of virtual 3D characters (called "Body SABA"), using in one object package of minimal costs and easy for operation.

iSocial: delivering the Social Competence Intervention for Adolescents (SCI-A) in a 3D virtual learning environment for youth with high functioning autism.

PubMed

Stichter, Janine P; Laffey, James; Galyen, Krista; Herzog, Melissa

2014-02-01

One consistent area of need for students with autism spectrum disorders is in the area of social competence. However, the increasing need to provide qualified teachers to deliver evidence-based practices in areas like social competence leave schools, such as those found in rural areas, in need of support. Distance education and in particular, 3D Virtual Learning, holds great promise for supporting schools and youth to gain social competence through knowledge and social practice in context. iSocial, a distance education, 3D virtual learning environment implemented the 31-lesson social competence intervention for adolescents across three small cohorts totaling 11 students over a period of 4 months. Results demonstrated that the social competence curriculum was delivered with fidelity in the 3D virtual learning environment. Moreover, learning outcomes suggest that the iSocial approach shows promise for social competence benefits for youth.

Implementation of virtual models from sheet metal forming simulation into physical 3D colour models using 3D printing

NASA Astrophysics Data System (ADS)

Junk, S.

2016-08-01

Today the methods of numerical simulation of sheet metal forming offer a great diversity of possibilities for optimization in product development and in process design. However, the results from simulation are only available as virtual models. Because there are any forming tools available during the early stages of product development, physical models that could serve to represent the virtual results are therefore lacking. Physical 3D-models can be created using 3D-printing and serve as an illustration and present a better understanding of the simulation results. In this way, the results from the simulation can be made more “comprehensible” within a development team. This paper presents the possibilities of 3D-colour printing with particular consideration of the requirements regarding the implementation of sheet metal forming simulation. Using concrete examples of sheet metal forming, the manufacturing of 3D colour models will be expounded upon on the basis of simulation results.

Transduction between worlds: using virtual and mixed reality for earth and planetary science

NASA Astrophysics Data System (ADS)

Hedley, N.; Lochhead, I.; Aagesen, S.; Lonergan, C. D.; Benoy, N.

2017-12-01

Virtual reality (VR) and augmented reality (AR) have the potential to transform the way we visualize multidimensional geospatial datasets in support of geoscience research, exploration and analysis. The beauty of virtual environments is that they can be built at any scale, users can view them at many levels of abstraction, move through them in unconventional ways, and experience spatial phenomena as if they had superpowers. Similarly, augmented reality allows you to bring the power of virtual 3D data visualizations into everyday spaces. Spliced together, these interface technologies hold incredible potential to support 21st-century geoscience. In my ongoing research, my team and I have made significant advances to connect data and virtual simulations with real geographic spaces, using virtual environments, geospatial augmented reality and mixed reality. These research efforts have yielded new capabilities to connect users with spatial data and phenomena. These innovations include: geospatial x-ray vision; flexible mixed reality; augmented 3D GIS; situated augmented reality 3D simulations of tsunamis and other phenomena interacting with real geomorphology; augmented visual analytics; and immersive GIS. These new modalities redefine the ways in which we can connect digital spaces of spatial analysis, simulation and geovisualization, with geographic spaces of data collection, fieldwork, interpretation and communication. In a way, we are talking about transduction between real and virtual worlds. Taking a mixed reality approach to this, we can link real and virtual worlds. This paper presents a selection of our 3D geovisual interface projects in terrestrial, coastal, underwater and other environments. Using rigorous applied geoscience data, analyses and simulations, our research aims to transform the novelty of virtual and augmented reality interface technologies into game-changing mixed reality geoscience.

Interactive 3D visualization for theoretical virtual observatories

NASA Astrophysics Data System (ADS)

Dykes, T.; Hassan, A.; Gheller, C.; Croton, D.; Krokos, M.

2018-06-01

Virtual observatories (VOs) are online hubs of scientific knowledge. They encompass a collection of platforms dedicated to the storage and dissemination of astronomical data, from simple data archives to e-research platforms offering advanced tools for data exploration and analysis. Whilst the more mature platforms within VOs primarily serve the observational community, there are also services fulfilling a similar role for theoretical data. Scientific visualization can be an effective tool for analysis and exploration of data sets made accessible through web platforms for theoretical data, which often contain spatial dimensions and properties inherently suitable for visualization via e.g. mock imaging in 2D or volume rendering in 3D. We analyse the current state of 3D visualization for big theoretical astronomical data sets through scientific web portals and virtual observatory services. We discuss some of the challenges for interactive 3D visualization and how it can augment the workflow of users in a virtual observatory context. Finally we showcase a lightweight client-server visualization tool for particle-based data sets, allowing quantitative visualization via data filtering, highlighting two example use cases within the Theoretical Astrophysical Observatory.

X3DOM as Carrier of the Virtual Heritage

NASA Astrophysics Data System (ADS)

Jung, Y.; Behr, J.; Graf, H.

2011-09-01

Virtual Museums (VM) are a new model of communication that aims at creating a personalized, immersive, and interactive way to enhance our understanding of the world around us. The term "VM" is a short-cut that comprehends various types of digital creations. One of the carriers for the communication of the virtual heritage at future internet level as de-facto standard is browser front-ends presenting the content and assets of museums. A major driving technology for the documentation and presentation of heritage driven media is real-time 3D content, thus imposing new strategies for a web inclusion. 3D content must become a first class web media that can be created, modified, and shared in the same way as text, images, audio and video are handled on the web right now. A new integration model based on a DOM integration into the web browsers' architecture opens up new possibilities for declarative 3 D content on the web and paves the way for new application scenarios for the virtual heritage at future internet level. With special regards to the X3DOM project as enabling technology for declarative 3D in HTML, this paper describes application scenarios and analyses its technological requirements for an efficient presentation and manipulation of virtual heritage assets on the web.

Recent advances in 3D computed tomography techniques for simulation and navigation in hepatobiliary pancreatic surgery.

PubMed

Uchida, Masafumi

2014-04-01

A few years ago it could take several hours to complete a 3D image using a 3D workstation. Thanks to advances in computer science, obtaining results of interest now requires only a few minutes. Many recent 3D workstations or multimedia computers are equipped with onboard 3D virtual patient modeling software, which enables patient-specific preoperative assessment and virtual planning, navigation, and tool positioning. Although medical 3D imaging can now be conducted using various modalities, including computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET), and ultrasonography (US) among others, the highest quality images are obtained using CT data, and CT images are now the most commonly used source of data for 3D simulation and navigation image. If the 2D source image is bad, no amount of 3D image manipulation in software will provide a quality 3D image. In this exhibition, the recent advances in CT imaging technique and 3D visualization of the hepatobiliary and pancreatic abnormalities are featured, including scan and image reconstruction technique, contrast-enhanced techniques, new application of advanced CT scan techniques, and new virtual reality simulation and navigation imaging. © 2014 Japanese Society of Hepato-Biliary-Pancreatic Surgery.

Sediment dynamics in shallow Lake Markermeer, The Netherlands: field/laboratory surveys and first results for a 3-D suspended solids model.

PubMed

Kelderman, P; De Rozari, P; Mukhopadhyay, S; Ang'weya, R O

2012-01-01

In 2007/08, a study was undertaken on sediment dynamics in shallow Lake Markermeer, The Netherlands. Firstly, the sediment characteristics median grain size, mud content and loss on ignition showed a spatial as well as water depth related pattern indicating wind-induced sediment transport. Sediment dynamics were investigated in a sediment trap field survey at two stations. Sediment yields, virtually all coming from sediment resuspension, were significantly correlated with wind speeds. Resuspension rates for Lake Markermeer were very high, viz. ca. 1,000 g/m(2)day as an annual average, leading to high suspended solids (SS) contents, due to the large lake area and its shallowness (high 'Dynamic Ratio'). Sediment resuspension behaviour was further investigated in preliminary laboratory experiments using a 'micro-flume', applying increasing water currents onto five Lake Markermeer sediments. Resuspension showed a clear exponential behaviour. Finally, a 3-D model was set up for water quality and SS contents in Lake Markermeer; first results showed a good agreement between modelled and actual SS contents. Construction of artificial islands and dams will reduce wind fetches and may be expected to cause a substantial decrease in lake water turbidity.

The Components of Effective Teacher Training in the Use of Three-Dimensional Immersive Virtual Worlds for Learning and Instruction Purposes: A Literature Review

ERIC Educational Resources Information Center

Nussli, Natalie; Oh, Kevin

2014-01-01

The overarching question that guides this review is to identify the key components of effective teacher training in virtual schooling, with a focus on three-dimensional (3D) immersive virtual worlds (IVWs). The process of identifying the essential components of effective teacher training in the use of 3D IVWs will be described step-by-step. First,…

Cross-Cultural Discussions in a 3D Virtual Environment and Their Affordances for Learners' Motivation and Foreign Language Discussion Skills

ERIC Educational Resources Information Center

Jauregi, Kristi; Kuure, Leena; Bastian, Pim; Reinhardt, Dennis; Koivisto, Tuomo

2015-01-01

Within the European TILA project a case study was carried out where pupils from schools in Finland and the Netherlands engaged in debating sessions using the 3D virtual world of OpenSim once a week for a period of 5 weeks. The case study had two main objectives: (1) to study the impact that the discussion tasks undertaken in a virtual environment…

An Interactive 3D Virtual Anatomy Puzzle for Learning and Simulation - Initial Demonstration and Evaluation.

PubMed

Messier, Erik; Wilcox, Jascha; Dawson-Elli, Alexander; Diaz, Gabriel; Linte, Cristian A

2016-01-01

To inspire young students (grades 6-12) to become medical practitioners and biomedical engineers, it is necessary to expose them to key concepts of the field in a way that is both exciting and informative. Recent advances in medical image acquisition, manipulation, processing, visualization, and display have revolutionized the approach in which the human body and internal anatomy can be seen and studied. It is now possible to collect 3D, 4D, and 5D medical images of patient specific data, and display that data to the end user using consumer level 3D stereoscopic display technology. Despite such advancements, traditional 2D modes of content presentation such as textbooks and slides are still the standard didactic equipment used to teach young students anatomy. More sophisticated methods of display can help to elucidate the complex 3D relationships between structures that are so often missed when viewing only 2D media, and can instill in students an appreciation for the interconnection between medicine and technology. Here we describe the design, implementation, and preliminary evaluation of a 3D virtual anatomy puzzle dedicated to helping users learn the anatomy of various organs and systems by manipulating 3D virtual data. The puzzle currently comprises several components of the human anatomy and can be easily extended to include additional organs and systems. The 3D virtual anatomy puzzle game was implemented and piloted using three display paradigms - a traditional 2D monitor, a 3D TV with active shutter glass, and the DK2 version Oculus Rift, as well as two different user interaction devices - a space mouse and traditional keyboard controls.

Real-time interactive virtual tour on the World Wide Web (WWW)

NASA Astrophysics Data System (ADS)

Yoon, Sanghyuk; Chen, Hai-jung; Hsu, Tom; Yoon, Ilmi

2003-12-01

Web-based Virtual Tour has become a desirable and demanded application, yet challenging due to the nature of web application's running environment such as limited bandwidth and no guarantee of high computation power on the client side. Image-based rendering approach has attractive advantages over traditional 3D rendering approach in such Web Applications. Traditional approach, such as VRML, requires labor-intensive 3D modeling process, high bandwidth and computation power especially for photo-realistic virtual scenes. QuickTime VR and IPIX as examples of image-based approach, use panoramic photos and the virtual scenes that can be generated from photos directly skipping the modeling process. But, these image-based approaches may require special cameras or effort to take panoramic views and provide only one fixed-point look-around and zooming in-out rather than 'walk around', that is a very important feature to provide immersive experience to virtual tourists. The Web-based Virtual Tour using Tour into the Picture employs pseudo 3D geometry with image-based rendering approach to provide viewers with immersive experience of walking around the virtual space with several snap shots of conventional photos.

Simulating 3D deformation using connected polygons

NASA Astrophysics Data System (ADS)

Tarigan, J. T.; Jaya, I.; Hardi, S. M.; Zamzami, E. M.

2018-03-01

In modern 3D application, interaction between user and the virtual world is one of an important factor to increase the realism. This interaction can be visualized in many forms; one of them is object deformation. There are many ways to simulate object deformation in virtual 3D world; each comes with different level of realism and performance. Our objective is to present a new method to simulate object deformation by using a graph-connected polygon. In this solution, each object contains multiple level of polygons in different level of volume. The proposed solution focusses on performance rather while maintaining the acceptable level of realism. In this paper, we present the design and implementation of our solution and show that this solution is usable in performance sensitive 3D application such as games and virtual reality.

Interreality: A New Paradigm for E-health.

PubMed

Riva, Giuseppe

2009-01-01

"Interreality" is a personalized immersive e-therapy whose main novelty is a hybrid, closed-loop empowering experience bridging physical and virtual worlds. The main feature of interreality is a twofold link between the virtual and the real world: (a) behavior in the physical world influences the experience in the virtual one; (b) behavior in the virtual world influences the experience in the real one. This is achieved through: (1) 3D Shared Virtual Worlds: role-playing experiences in which one or more users interact with one another within a 3D world; (2) Bio and Activity Sensors (From the Real to the Virtual World): They are used to track the emotional/health/activity status of the user and to influence his/her experience in the virtual world (aspect, activity and access); (3) Mobile Internet Appliances (From the Virtual to the Real One): In interreality, the social and individual user activity in the virtual world has a direct link with the users' life through a mobile phone/digital assistant. The different technologies that are involved in the interreality vision and its clinical rationale are addressed and discussed.

Virtual Representations in 3D Learning Environments

ERIC Educational Resources Information Center

Shonfeld, Miri; Kritz, Miki

2013-01-01

This research explores the extent to which virtual worlds can serve as online collaborative learning environments for students by increasing social presence and engagement. 3D environments enable learning, which simulates face-to-face encounters while retaining the advantages of online learning. Students in Education departments created avatars…

fVisiOn: glasses-free tabletop 3D display to provide virtual 3D media naturally alongside real media

NASA Astrophysics Data System (ADS)

Yoshida, Shunsuke

2012-06-01

A novel glasses-free tabletop 3D display, named fVisiOn, floats virtual 3D objects on an empty, flat, tabletop surface and enables multiple viewers to observe raised 3D images from any angle at 360° Our glasses-free 3D image reproduction method employs a combination of an optical device and an array of projectors and produces continuous horizontal parallax in the direction of a circular path located above the table. The optical device shapes a hollow cone and works as an anisotropic diffuser. The circularly arranged projectors cast numerous rays into the optical device. Each ray represents a particular ray that passes a corresponding point on a virtual object's surface and orients toward a viewing area around the table. At any viewpoint on the ring-shaped viewing area, both eyes collect fractional images from different projectors, and all the viewers around the table can perceive the scene as 3D from their perspectives because the images include binocular disparity. The entire principle is installed beneath the table, so the tabletop area remains clear. No ordinary tabletop activities are disturbed. Many people can naturally share the 3D images displayed together with real objects on the table. In our latest prototype, we employed a handmade optical device and an array of over 100 tiny projectors. This configuration reproduces static and animated 3D scenes for a 130° viewing area and allows 5-cm-tall virtual characters to play soccer and dance on the table.

Re-Dimensional Thinking in Earth Science: From 3-D Virtual Reality Panoramas to 2-D Contour Maps

ERIC Educational Resources Information Center

Park, John; Carter, Glenda; Butler, Susan; Slykhuis, David; Reid-Griffin, Angelia

2008-01-01

This study examines the relationship of gender and spatial perception on student interactivity with contour maps and non-immersive virtual reality. Eighteen eighth-grade students elected to participate in a six-week activity-based course called "3-D GeoMapping." The course included nine days of activities related to topographic mapping.…

Design and implementation of a 3D ocean virtual reality and visualization engine

NASA Astrophysics Data System (ADS)

Chen, Ge; Li, Bo; Tian, Fenglin; Ji, Pengbo; Li, Wenqing

2012-12-01

In this study, a 3D virtual reality and visualization engine for rendering the ocean, named VV-Ocean, is designed for marine applications. The design goals of VV-Ocean aim at high fidelity simulation of ocean environment, visualization of massive and multidimensional marine data, and imitation of marine lives. VV-Ocean is composed of five modules, i.e. memory management module, resources management module, scene management module, rendering process management module and interaction management module. There are three core functions in VV-Ocean: reconstructing vivid virtual ocean scenes, visualizing real data dynamically in real time, imitating and simulating marine lives intuitively. Based on VV-Ocean, we establish a sea-land integration platform which can reproduce drifting and diffusion processes of oil spilling from sea bottom to surface. Environment factors such as ocean current and wind field have been considered in this simulation. On this platform oil spilling process can be abstracted as movements of abundant oil particles. The result shows that oil particles blend with water well and the platform meets the requirement for real-time and interactive rendering. VV-Ocean can be widely used in ocean applications such as demonstrating marine operations, facilitating maritime communications, developing ocean games, reducing marine hazards, forecasting the weather over oceans, serving marine tourism, and so on. Finally, further technological improvements of VV-Ocean are discussed.

Interface for Physics Simulation Engines

NASA Technical Reports Server (NTRS)

Damer, Bruce

2007-01-01

DSS-Prototyper is an open-source, realtime 3D virtual environment software that supports design simulation for the new Vision for Space Exploration (VSE). This is a simulation of NASA's proposed Robotic Lunar Exploration Program, second mission (RLEP2). It simulates the Lunar Surface Access Module (LSAM), which is designed to carry up to four astronauts to the lunar surface for durations of a week or longer. This simulation shows the virtual vehicle making approaches and landings on a variety of lunar terrains. The physics of the descent engine thrust vector, production of dust, and the dynamics of the suspension are all modeled in this set of simulations. The RLEP2 simulations are drivable (by keyboard or joystick) virtual rovers with controls for speed and motor torque, and can be articulated into higher or lower centers of gravity (depending on driving hazards) to enable drill placement. Gravity also can be set to lunar, terrestrial, or zero-g. This software has been used to support NASA's Marshall Space Flight Center in simulations of proposed vehicles for robotically exploring the lunar surface for water ice, and could be used to model all other aspects of the VSE from the Ares launch vehicles and Crew Exploration Vehicle (CEV) to the International Space Station (ISS). This simulator may be installed and operated on any Windows PC with an installed 3D graphics card.

A Comparative Analysis of 2D and 3D Tasks for Virtual Reality Therapies Based on Robotic-Assisted Neurorehabilitation for Post-stroke Patients

PubMed Central

Lledó, Luis D.; Díez, Jorge A.; Bertomeu-Motos, Arturo; Ezquerro, Santiago; Badesa, Francisco J.; Sabater-Navarro, José M.; García-Aracil, Nicolás

2016-01-01

Post-stroke neurorehabilitation based on virtual therapies are performed completing repetitive exercises shown in visual electronic devices, whose content represents imaginary or daily life tasks. Currently, there are two ways of visualization of these task. 3D virtual environments are used to get a three dimensional space that represents the real world with a high level of detail, whose realism is determinated by the resolucion and fidelity of the objects of the task. Furthermore, 2D virtual environments are used to represent the tasks with a low degree of realism using techniques of bidimensional graphics. However, the type of visualization can influence the quality of perception of the task, affecting the patient's sensorimotor performance. The purpose of this paper was to evaluate if there were differences in patterns of kinematic movements when post-stroke patients performed a reach task viewing a virtual therapeutic game with two different type of visualization of virtual environment: 2D and 3D. Nine post-stroke patients have participated in the study receiving a virtual therapy assisted by PUPArm rehabilitation robot. Horizontal movements of the upper limb were performed to complete the aim of the tasks, which consist in reaching peripheral or perspective targets depending on the virtual environment shown. Various parameter types such as the maximum speed, reaction time, path length, or initial movement are analyzed from the data acquired objectively by the robotic device to evaluate the influence of the task visualization. At the end of the study, a usability survey was provided to each patient to analysis his/her satisfaction level. For all patients, the movement trajectories were enhanced when they completed the therapy. This fact suggests that patient's motor recovery was increased. Despite of the similarity in majority of the kinematic parameters, differences in reaction time and path length were higher using the 3D task. Regarding the success rates were very similar. In conclusion, the using of 2D environments in virtual therapy may be a more appropriate and comfortable way to perform tasks for upper limb rehabilitation of post-stroke patients, in terms of accuracy in order to effectuate optimal kinematic trajectories. PMID:27616992

Research on The Construction of Flexible Multi-body Dynamics Model based on Virtual Components

NASA Astrophysics Data System (ADS)

Dong, Z. H.; Ye, X.; Yang, F.

2018-05-01

Focus on the harsh operation condition of space manipulator, which cannot afford relative large collision momentum, this paper proposes a new concept and technology, called soft-contact technology. In order to solve the problem of collision dynamics of flexible multi-body system caused by this technology, this paper also proposes the concepts of virtual components and virtual hinges, and constructs flexible dynamic model based on virtual components, and also studies on its solutions. On this basis, this paper uses NX to carry out model and comparison simulation for space manipulator in 3 different modes. The results show that using the model of multi-rigid body + flexible body hinge + controllable damping can make effective control on amplitude for the force and torque caused by target satellite collision.

Real-Time Simulation

NASA Technical Reports Server (NTRS)

1997-01-01

Coryphaeus Software, founded in 1989 by former NASA electronic engineer Steve Lakowske, creates real-time 3D software. Designer's Workbench, the company flagship product, is a modeling and simulation tool for the development of both static and dynamic 3D databases. Other products soon followed. Activation, specifically designed for game developers, allows developers to play and test the 3D games before they commit to a target platform. Game publishers can shorten development time and prove the "playability" of the title, maximizing their chances of introducing a smash hit. Another product, EasyT, lets users create massive, realistic representation of Earth terrains that can be viewed and traversed in real time. Finally, EasyScene software control the actions among interactive objects within a virtual world. Coryphaeus products are used on Silican Graphics workstation and supercomputers to simulate real-world performance in synthetic environments. Customers include aerospace, aviation, architectural and engineering firms, game developers, and the entertainment industry.

Co-located haptic and 3D graphic interface for medical simulations.

PubMed

Berkelman, Peter; Miyasaka, Muneaki; Bozlee, Sebastian

2013-01-01

We describe a system which provides high-fidelity haptic feedback in the same physical location as a 3D graphical display, in order to enable realistic physical interaction with virtual anatomical tissue during modelled procedures such as needle driving, palpation, and other interventions performed using handheld instruments. The haptic feedback is produced by the interaction between an array of coils located behind a thin flat LCD screen, and permanent magnets embedded in the instrument held by the user. The coil and magnet configuration permits arbitrary forces and torques to be generated on the instrument in real time according to the dynamics of the simulated tissue by activating the coils in combination. A rigid-body motion tracker provides position and orientation feedback of the handheld instrument to the computer simulation, and the 3D display is produced using LCD shutter glasses and a head-tracking system for the user.

[The virtual reality simulation research of China Mechanical Virtual Human based on the Creator/Vega].

PubMed

Wei, Gaofeng; Tang, Gang; Fu, Zengliang; Sun, Qiuming; Tian, Feng

2010-10-01

The China Mechanical Virtual Human (CMVH) is a human musculoskeletal biomechanical simulation platform based on China Visible Human slice images; it has great realistic application significance. In this paper is introduced the construction method of CMVH 3D models. Then a simulation system solution based on Creator/Vega is put forward for the complex and gigantic data characteristics of the 3D models. At last, combined with MFC technology, the CMVH simulation system is developed and a running simulation scene is given. This paper provides a new way for the virtual reality application of CMVH.

Virtual Reality Website of Indonesia National Monument and Its Environment

NASA Astrophysics Data System (ADS)

Wardijono, B. A.; Hendajani, F.; Sudiro, S. A.

2017-02-01

National Monument (Monumen Nasional) is an Indonesia National Monument building where located in Jakarta. This monument is a symbol of Jakarta and it is a pride monument of the people in Jakarta and Indonesia country. This National Monument also has a museum about the history of the Indonesian country. To provide information to the general public, in this research we created and developed models of 3D graphics from the National Monument and the surrounding environment. Virtual Reality technology was used to display the visualization of the National Monument and the surrounding environment in 3D graphics form. Latest programming technology makes it possible to display 3D objects via the internet browser. This research used Unity3D and WebGL to make virtual reality models that can be implemented and showed on a Website. The result from this research is the development of 3-dimensional Website of the National Monument and its objects surrounding the environment that can be displayed through the Web browser. The virtual reality of whole objects was divided into a number of scenes, so that it can be displayed in real time visualization.

Navigation system for robot-assisted intra-articular lower-limb fracture surgery.

PubMed

Dagnino, Giulio; Georgilas, Ioannis; Köhler, Paul; Morad, Samir; Atkins, Roger; Dogramadzi, Sanja

2016-10-01

In the surgical treatment for lower-leg intra-articular fractures, the fragments have to be positioned and aligned to reconstruct the fractured bone as precisely as possible, to allow the joint to function correctly again. Standard procedures use 2D radiographs to estimate the desired reduction position of bone fragments. However, optimal correction in a 3D space requires 3D imaging. This paper introduces a new navigation system that uses pre-operative planning based on 3D CT data and intra-operative 3D guidance to virtually reduce lower-limb intra-articular fractures. Physical reduction in the fractures is then performed by our robotic system based on the virtual reduction. 3D models of bone fragments are segmented from CT scan. Fragments are pre-operatively visualized on the screen and virtually manipulated by the surgeon through a dedicated GUI to achieve the virtual reduction in the fracture. Intra-operatively, the actual position of the bone fragments is provided by an optical tracker enabling real-time 3D guidance. The motion commands for the robot connected to the bone fragment are generated, and the fracture physically reduced based on the surgeon's virtual reduction. To test the system, four femur models were fractured to obtain four different distal femur fracture types. Each one of them was subsequently reduced 20 times by a surgeon using our system. The navigation system allowed an orthopaedic surgeon to virtually reduce the fracture with a maximum residual positioning error of [Formula: see text] (translational) and [Formula: see text] (rotational). Correspondent physical reductions resulted in an accuracy of 1.03 ± 0.2 mm and [Formula: see text], when the robot reduced the fracture. Experimental outcome demonstrates the accuracy and effectiveness of the proposed navigation system, presenting a fracture reduction accuracy of about 1 mm and [Formula: see text], and meeting the clinical requirements for distal femur fracture reduction procedures.

High-performance multiprocessor architecture for a 3-D lattice gas model

NASA Technical Reports Server (NTRS)

Lee, F.; Flynn, M.; Morf, M.

1991-01-01

The lattice gas method has recently emerged as a promising discrete particle simulation method in areas such as fluid dynamics. We present a very high-performance scalable multiprocessor architecture, called ALGE, proposed for the simulation of a realistic 3-D lattice gas model, Henon's 24-bit FCHC isometric model. Each of these VLSI processors is as powerful as a CRAY-2 for this application. ALGE is scalable in the sense that it achieves linear speedup for both fixed and increasing problem sizes with more processors. The core computation of a lattice gas model consists of many repetitions of two alternating phases: particle collision and propagation. Functional decomposition by symmetry group and virtual move are the respective keys to efficient implementation of collision and propagation.

The Avignon Bridge: a 3d Reconstruction Project Integrating Archaeological, Historical and Gemorphological Issues

NASA Astrophysics Data System (ADS)

Berthelot, M.; Nony, N.; Gugi, L.; Bishop, A.; De Luca, L.

2015-02-01

The history and identity of the Avignon's bridge is inseparable from that of the Rhône river. Therefore, in order to share the history and memory of the Rhône, it is essential to get to know this bridge and especially to identify and make visible the traces of its past, its construction, its interaction with the river dynamics, which greatly influenced his life. These are the objectives of the PAVAGE project that focuses on digitally surveying, modelling and re-visiting a heritage site of primary importance with the aim of virtually restoring the link between the two sides which, after the disappearance of the Roman bridge of Arles, constituted for a long time the only connection between Lyon or Vienna and the sea. Therefore, this project has an important geo-historical dimension for which geo-morphological and paleoenvironmental studies were implemented in connection with the latest digital simulation methods exploiting geographic information systems. By integrating knowledge and reflections of archaeologists, historians, geomorphologists, environmentalists, architects, engineers and computer scientists, the result of this project (which involved 5 laboratories during 4 years) is a 3D digital model covering an extension of 50 km2 achieved by integrating satellite imagery, UAV-based acquisitions, terrestrial laser scanning and photogrammetry, etc. Beyond the actions of scientific valorisation concerning the historical and geomorphological dimensions of the project, the results of this work of this interdisciplinary investigation and interpretation of this site are today integrated within a location-based augmented reality application allowing tourists to exploring the virtual reconstruction of the bridge and its environment through tablets inside the portion of territory covered by this project (between Avignon and Villeneuve-lez-Avignon). This paper presents the main aspects of the 3D virtual reconstruction approach.

User Interface Technology Transfer to NASA's Virtual Wind Tunnel System

NASA Technical Reports Server (NTRS)

vanDam, Andries

1998-01-01

Funded by NASA grants for four years, the Brown Computer Graphics Group has developed novel 3D user interfaces for desktop and immersive scientific visualization applications. This past grant period supported the design and development of a software library, the 3D Widget Library, which supports the construction and run-time management of 3D widgets. The 3D Widget Library is a mechanism for transferring user interface technology from the Brown Graphics Group to the Virtual Wind Tunnel system at NASA Ames as well as the public domain.

A Second Life for eHealth: Prospects for the Use of 3-D Virtual Worlds in Clinical Psychology

PubMed Central

Gaggioli, Andrea; Vigna, Cinzia; Riva, Giuseppe

2008-01-01

The aim of the present paper is to describe the role played by three-dimensional (3-D) virtual worlds in eHealth applications, addressing some potential advantages and issues related to the use of this emerging medium in clinical practice. Due to the enormous diffusion of the World Wide Web (WWW), telepsychology, and telehealth in general, have become accepted and validated methods for the treatment of many different health care concerns. The introduction of the Web 2.0 has facilitated the development of new forms of collaborative interaction between multiple users based on 3-D virtual worlds. This paper describes the development and implementation of a form of tailored immersive e-therapy called p-health whose key factor is interreality, that is, the creation of a hybrid augmented experience merging physical and virtual worlds. We suggest that compared with conventional telehealth applications such as emails, chat, and videoconferences, the interaction between real and 3-D virtual worlds may convey greater feelings of presence, facilitate the clinical communication process, positively influence group processes and cohesiveness in group-based therapies, and foster higher levels of interpersonal trust between therapists and patients. However, challenges related to the potentially addictive nature of such virtual worlds and questions related to privacy and personal safety will also be discussed. PMID:18678557

A randomized, double-blind evaluation of D-cycloserine or alprazolam combined with virtual reality exposure therapy for posttraumatic stress disorder in Iraq and Afghanistan War veterans.

PubMed

Rothbaum, Barbara Olasov; Price, Matthew; Jovanovic, Tanja; Norrholm, Seth D; Gerardi, Maryrose; Dunlop, Boadie; Davis, Michael; Bradley, Bekh; Duncan, Erica J; Rizzo, Albert; Ressler, Kerry J

2014-06-01

The authors examined the effectiveness of virtual reality exposure augmented with D-cycloserine or alprazolam, compared with placebo, in reducing posttraumatic stress disorder (PTSD) due to military trauma. After an introductory session, five sessions of virtual reality exposure were augmented with D-cycloserine (50 mg) or alprazolam (0.25 mg) in a double-blind, placebo-controlled randomized clinical trial for 156 Iraq and Afghanistan war veterans with PTSD. PTSD symptoms significantly improved from pre- to posttreatment across all conditions and were maintained at 3, 6, and 12 months. There were no overall differences in symptoms between D-cycloserine and placebo at any time. Alprazolam and placebo differed significantly on the Clinician-Administered PTSD Scale score at posttreatment and PTSD diagnosis at 3 months posttreatment; the alprazolam group showed a higher rate of PTSD (82.8%) than the placebo group (47.8%). Between-session extinction learning was a treatment-specific enhancer of outcome for the D-cycloserine group only. At posttreatment, the D-cycloserine group had the lowest cortisol reactivity and smallest startle response during virtual reality scenes. A six-session virtual reality treatment was associated with reduction in PTSD diagnoses and symptoms in Iraq and Afghanistan veterans, although there was no control condition for the virtual reality exposure. There was no advantage of D-cycloserine for PTSD symptoms in primary analyses. In secondary analyses, alprazolam impaired recovery and D-cycloserine enhanced virtual reality outcome in patients who demonstrated within-session learning. D-cycloserine augmentation reduced cortisol and startle reactivity more than did alprazolam or placebo, findings that are consistent with those in the animal literature.

Magical Stories: Blending Virtual Reality and Artificial Intelligence.

ERIC Educational Resources Information Center

McLellan, Hilary

Artificial intelligence (AI) techniques and virtual reality (VR) make possible powerful interactive stories, and this paper focuses on examples of virtual characters in three dimensional (3-D) worlds. Waldern, a virtual reality game designer, has theorized about and implemented software design of virtual teammates and opponents that incorporate AI…

Virtual hand: a 3D tactile interface to virtual environments

NASA Astrophysics Data System (ADS)

Rogowitz, Bernice E.; Borrel, Paul

2008-02-01

We introduce a novel system that allows users to experience the sensation of touch in a computer graphics environment. In this system, the user places his/her hand on an array of pins, which is moved about space on a 6 degree-of-freedom robot arm. The surface of the pins defines a surface in the virtual world. This "virtual hand" can move about the virtual world. When the virtual hand encounters an object in the virtual world, the heights of the pins are adjusted so that they represent the object's shape, surface, and texture. A control system integrates pin and robot arm motions to transmit information about objects in the computer graphics world to the user. It also allows the user to edit, change and move the virtual objects, shapes and textures. This system provides a general framework for touching, manipulating, and modifying objects in a 3-D computer graphics environment, which may be useful in a wide range of applications, including computer games, computer aided design systems, and immersive virtual worlds.

3D virtual human atria: A computational platform for studying clinical atrial fibrillation

PubMed Central

Aslanidi, Oleg V; Colman, Michael A; Stott, Jonathan; Dobrzynski, Halina; Boyett, Mark R; Holden, Arun V; Zhang, Henggui

2011-01-01

Despite a vast amount of experimental and clinical data on the underlying ionic, cellular and tissue substrates, the mechanisms of common atrial arrhythmias (such as atrial fibrillation, AF) arising from the functional interactions at the whole atria level remain unclear. Computational modelling provides a quantitative framework for integrating such multi-scale data and understanding the arrhythmogenic behaviour that emerges from the collective spatio-temporal dynamics in all parts of the heart. In this study, we have developed a multi-scale hierarchy of biophysically detailed computational models for the human atria – 3D virtual human atria. Primarily, diffusion tensor MRI reconstruction of the tissue geometry and fibre orientation in the human sinoatrial node (SAN) and surrounding atrial muscle was integrated into the 3D model of the whole atria dissected from the Visible Human dataset. The anatomical models were combined with the heterogeneous atrial action potential (AP) models, and used to simulate the AP conduction in the human atria under various conditions: SAN pacemaking and atrial activation in the normal rhythm, break-down of regular AP wave-fronts during rapid atrial pacing, and the genesis of multiple re-entrant wavelets characteristic of AF. Contributions of different properties of the tissue to the mechanisms of the normal rhythm and AF arrhythmogenesis are investigated and discussed. The 3D model of the atria itself was incorporated into the torso model to simulate the body surface ECG patterns in the normal and arrhythmic conditions. Therefore, a state-of-the-art computational platform has been developed, which can be used for studying multi-scale electrical phenomena during atrial conduction and arrhythmogenesis. Results of such simulations can be directly compared with experimental electrophysiological and endocardial mapping data, as well as clinical ECG recordings. More importantly, the virtual human atria can provide validated means for directly dissecting 3D excitation propagation processes within the atrial walls from an in vivo whole heart, which are beyond the current technical capabilities of experimental or clinical set-ups. PMID:21762716

Three-dimensional virtual acoustic displays

NASA Technical Reports Server (NTRS)

Wenzel, Elizabeth M.

1991-01-01

The development of an alternative medium for displaying information in complex human-machine interfaces is described. The 3-D virtual acoustic display is a means for accurately transferring information to a human operator using the auditory modality; it combines directional and semantic characteristics to form naturalistic representations of dynamic objects and events in remotely sensed or simulated environments. Although the technology can stand alone, it is envisioned as a component of a larger multisensory environment and will no doubt find its greatest utility in that context. The general philosophy in the design of the display has been that the development of advanced computer interfaces should be driven first by an understanding of human perceptual requirements, and later by technological capabilities or constraints. In expanding on this view, current and potential uses are addressed of virtual acoustic displays, such displays are characterized, and recent approaches to their implementation and application are reviewed, the research project at NASA-Ames is described in detail, and finally some critical research issues for the future are outlined.

A new approach towards image based virtual 3D city modeling by using close range photogrammetry

NASA Astrophysics Data System (ADS)

Singh, S. P.; Jain, K.; Mandla, V. R.

2014-05-01

3D city model is a digital representation of the Earth's surface and it's related objects such as building, tree, vegetation, and some manmade feature belonging to urban area. The demand of 3D city modeling is increasing day to day for various engineering and non-engineering applications. Generally three main image based approaches are using for virtual 3D city models generation. In first approach, researchers used Sketch based modeling, second method is Procedural grammar based modeling and third approach is Close range photogrammetry based modeling. Literature study shows that till date, there is no complete solution available to create complete 3D city model by using images. These image based methods also have limitations This paper gives a new approach towards image based virtual 3D city modeling by using close range photogrammetry. This approach is divided into three sections. First, data acquisition process, second is 3D data processing, and third is data combination process. In data acquisition process, a multi-camera setup developed and used for video recording of an area. Image frames created from video data. Minimum required and suitable video image frame selected for 3D processing. In second section, based on close range photogrammetric principles and computer vision techniques, 3D model of area created. In third section, this 3D model exported to adding and merging of other pieces of large area. Scaling and alignment of 3D model was done. After applying the texturing and rendering on this model, a final photo-realistic textured 3D model created. This 3D model transferred into walk-through model or in movie form. Most of the processing steps are automatic. So this method is cost effective and less laborious. Accuracy of this model is good. For this research work, study area is the campus of department of civil engineering, Indian Institute of Technology, Roorkee. This campus acts as a prototype for city. Aerial photography is restricted in many country and high resolution satellite images are costly. In this study, proposed method is based on only simple video recording of area. Thus this proposed method is suitable for 3D city modeling. Photo-realistic, scalable, geo-referenced virtual 3D city model is useful for various kinds of applications such as for planning in navigation, tourism, disasters management, transportations, municipality, urban and environmental managements, real-estate industry. Thus this study will provide a good roadmap for geomatics community to create photo-realistic virtual 3D city model by using close range photogrammetry.

Using virtual ridge augmentation and 3D printing to fabricate a titanium mesh positioning device: A novel technique letter.

PubMed

Al-Ardah, Aladdin; Alqahtani, Nasser; AlHelal, Abdulaziz; Goodacre, Brian; Swamidass, Rajesh; Garbacea, Antoanela; Lozada, Jaime

2018-05-02

This technique describes a novel approach for planning and augmenting a large bony defect using a titanium mesh (TiMe). A 3-dimensional (3D) surgical model was virtually created from a cone beam computed tomography (CBCT) and wax-pattern of the final prosthetic outcome. The required bone volume (horizontally and vertically) was digitally augmented and then 3D printed to create a bone model. The 3D model was then used to contour the TiMe in accordance with the digital augmentation. With the contoured / preformed TiMe on the 3D printed model a positioning jig was made to aid the placement of the TiMe as planned during surgery. Although this technique does not impact the final outcome of the augmentation procedure, it allows the clinician to virtually design the augmentation, preform and contour the TiMe, and create a positioning jig reducing surgical time and error.

The New Realm of 3-D Vision

NASA Technical Reports Server (NTRS)

2002-01-01

Dimension Technologies Inc., developed a line of 2-D/3-D Liquid Crystal Display (LCD) screens, including a 15-inch model priced at consumer levels. DTI's family of flat panel LCD displays, called the Virtual Window(TM), provide real-time 3-D images without the use of glasses, head trackers, helmets, or other viewing aids. Most of the company initial 3-D display research was funded through NASA's Small Business Innovation Research (SBIR) program. The images on DTI's displays appear to leap off the screen and hang in space. The display accepts input from computers or stereo video sources, and can be switched from 3-D to full-resolution 2-D viewing with the push of a button. The Virtual Window displays have applications in data visualization, medicine, architecture, business, real estate, entertainment, and other research, design, military, and consumer applications. Displays are currently used for computer games, protein analysis, and surgical imaging. The technology greatly benefits the medical field, as surgical simulators are helping to increase the skills of surgical residents. Virtual Window(TM) is a trademark of Dimension Technologies Inc.

A Study of Multi-Representation of Geometry Problem Solving with Virtual Manipulatives and Whiteboard System

ERIC Educational Resources Information Center

Hwang, Wu-Yuin; Su, Jia-Han; Huang, Yueh-Min; Dong, Jian-Jie

2009-01-01

In this paper, the development of an innovative Virtual Manipulatives and Whiteboard (VMW) system is described. The VMW system allowed users to manipulate virtual objects in 3D space and find clues to solve geometry problems. To assist with multi-representation transformation, translucent multimedia whiteboards were used to provide a virtual 3D…

Virtual embryology: a 3D library reconstructed from human embryo sections and animation of development process.

PubMed

Komori, M; Miura, T; Shiota, K; Minato, K; Takahashi, T

1995-01-01

The volumetric shape of a human embryo and its development is hard to comprehend as they have been viewed as a 2D schemes in a textbook or microscopic sectional image. In this paper, a CAI and research support system for human embryology using multimedia presentation techniques is described. In this system, 3D data is acquired from a series of sliced specimens. Its 3D structure can be viewed interactively by rotating, extracting, and truncating its whole body or organ. Moreover, the development process of embryos can be animated using a morphing technique applied to the specimen in several stages. The system is intended to be used interactively, like a virtual reality system. Hence, the system is called Virtual Embryology.

Virtual Reality in Neurointervention.

PubMed

Ong, Chin Siang; Deib, Gerard; Yesantharao, Pooja; Qiao, Ye; Pakpoor, Jina; Hibino, Narutoshi; Hui, Ferdinand; Garcia, Juan R

2018-06-01

Virtual reality (VR) allows users to experience realistic, immersive 3D virtual environments with the depth perception and binocular field of view of real 3D settings. Newer VR technology has now allowed for interaction with 3D objects within these virtual environments through the use of VR controllers. This technical note describes our preliminary experience with VR as an adjunct tool to traditional angiographic imaging in the preprocedural workup of a patient with a complex pseudoaneurysm. Angiographic MRI data was imported and segmented to create 3D meshes of bilateral carotid vasculature. The 3D meshes were then projected into VR space, allowing the operator to inspect the carotid vasculature using a 3D VR headset as well as interact with the pseudoaneurysm (handling, rotation, magnification, and sectioning) using two VR controllers. 3D segmentation of a complex pseudoaneurysm in the distal cervical segment of the right internal carotid artery was successfully performed and projected into VR. Conventional and VR visualization modes were equally effective in identifying and classifying the pathology. VR visualization allowed the operators to manipulate the dataset to achieve a greater understanding of the anatomy of the parent vessel, the angioarchitecture of the pseudoaneurysm, and the surface contours of all visualized structures. This preliminary study demonstrates the feasibility of utilizing VR for preprocedural evaluation in patients with anatomically complex neurovascular disorders. This novel visualization approach may serve as a valuable adjunct tool in deciding patient-specific treatment plans and selection of devices prior to intervention.

Recent results in visual servoing

NASA Astrophysics Data System (ADS)

Chaumette, François

2008-06-01

Visual servoing techniques consist in using the data provided by a vision sensor in order to control the motions of a dynamic system. Such systems are usually robot arms, mobile robots, aerial robots,… but can also be virtual robots for applications in computer animation, or even a virtual camera for applications in computer vision and augmented reality. A large variety of positioning tasks, or mobile target tracking, can be implemented by controlling from one to all the degrees of freedom of the system. Whatever the sensor configuration, which can vary from one on-board camera on the robot end-effector to several free-standing cameras, a set of visual features has to be selected at best from the image measurements available, allowing to control the degrees of freedom desired. A control law has also to be designed so that these visual features reach a desired value, defining a correct realization of the task. With a vision sensor providing 2D measurements, potential visual features are numerous, since as well 2D data (coordinates of feature points in the image, moments, …) as 3D data provided by a localization algorithm exploiting the extracted 2D measurements can be considered. It is also possible to combine 2D and 3D visual features to take the advantages of each approach while avoiding their respective drawbacks. From the selected visual features, the behavior of the system will have particular properties as for stability, robustness with respect to noise or to calibration errors, robot 3D trajectory, etc. The talk will present the main basic aspects of visual servoing, as well as technical advances obtained recently in the field inside the Lagadic group at INRIA/INRISA Rennes. Several application results will be also described.

Novel 3D/VR interactive environment for MD simulations, visualization and analysis.

PubMed

Doblack, Benjamin N; Allis, Tim; Dávila, Lilian P

2014-12-18

The increasing development of computing (hardware and software) in the last decades has impacted scientific research in many fields including materials science, biology, chemistry and physics among many others. A new computational system for the accurate and fast simulation and 3D/VR visualization of nanostructures is presented here, using the open-source molecular dynamics (MD) computer program LAMMPS. This alternative computational method uses modern graphics processors, NVIDIA CUDA technology and specialized scientific codes to overcome processing speed barriers common to traditional computing methods. In conjunction with a virtual reality system used to model materials, this enhancement allows the addition of accelerated MD simulation capability. The motivation is to provide a novel research environment which simultaneously allows visualization, simulation, modeling and analysis. The research goal is to investigate the structure and properties of inorganic nanostructures (e.g., silica glass nanosprings) under different conditions using this innovative computational system. The work presented outlines a description of the 3D/VR Visualization System and basic components, an overview of important considerations such as the physical environment, details on the setup and use of the novel system, a general procedure for the accelerated MD enhancement, technical information, and relevant remarks. The impact of this work is the creation of a unique computational system combining nanoscale materials simulation, visualization and interactivity in a virtual environment, which is both a research and teaching instrument at UC Merced.

Novel 3D/VR Interactive Environment for MD Simulations, Visualization and Analysis

PubMed Central

Doblack, Benjamin N.; Allis, Tim; Dávila, Lilian P.

2014-01-01

The increasing development of computing (hardware and software) in the last decades has impacted scientific research in many fields including materials science, biology, chemistry and physics among many others. A new computational system for the accurate and fast simulation and 3D/VR visualization of nanostructures is presented here, using the open-source molecular dynamics (MD) computer program LAMMPS. This alternative computational method uses modern graphics processors, NVIDIA CUDA technology and specialized scientific codes to overcome processing speed barriers common to traditional computing methods. In conjunction with a virtual reality system used to model materials, this enhancement allows the addition of accelerated MD simulation capability. The motivation is to provide a novel research environment which simultaneously allows visualization, simulation, modeling and analysis. The research goal is to investigate the structure and properties of inorganic nanostructures (e.g., silica glass nanosprings) under different conditions using this innovative computational system. The work presented outlines a description of the 3D/VR Visualization System and basic components, an overview of important considerations such as the physical environment, details on the setup and use of the novel system, a general procedure for the accelerated MD enhancement, technical information, and relevant remarks. The impact of this work is the creation of a unique computational system combining nanoscale materials simulation, visualization and interactivity in a virtual environment, which is both a research and teaching instrument at UC Merced. PMID:25549300

Virtual museum of Japanese Buddhist temple features for intercultural communication

NASA Astrophysics Data System (ADS)

Kawai, Takashi; Takao, Hidenobu; Inoue, Tetsuri; Miyamoto, Hiroyuki; Noro, Kageyu

1998-04-01

This paper describes the production and presentation of an experimental virtual museum of Japanese Buddhist art. This medium can provide an easy way to introduce a cultural heritage to people of different cultures. The virtual museum consisted of a multimedia program that included stereoscopic 3D movies of Buddhist statues; binaural 3D sounds of Buddhist ceremonies and the fragrance of incense from the Buddhist temple. The aim was to reproduce both the Buddhist artifacts and atmosphere as realistically as possible.

Pharmacophore Based 3D-QSAR, Virtual Screening and Docking Studies on Novel Series of HDAC Inhibitors with Thiophen Linker as Anticancer Agents.

PubMed

Patel, Preeti; Singh, Avineesh; Patel, Vijay K; Jain, Deepak K; Veerasamy, Ravichandran; Rajak, Harish

2016-01-01

Histone deacetylase (HDAC) inhibitors can reactivate gene expression and inhibit the growth and survival of cancer cells. To identify the important pharmacophoric features and correlate 3Dchemical structure with biological activity using 3D-QSAR and Pharmacophore modeling studies. The pharmacophore hypotheses were developed using e-pharmacophore script and phase module. Pharmacophore hypothesis represents the 3D arrangement of molecular features necessary for activity. A series of 55 compounds with wellassigned HDAC inhibitory activity were used for 3D-QSAR model development. Best 3D-QSAR model, which is a five partial least square (PLS) factor model with good statistics and predictive ability, acquired Q2 (0.7293), R2 (0.9811), cross-validated coefficient rcv 2=0.9807 and R2 pred=0.7147 with low standard deviation (0.0952). Additionally, the selected pharmacophore model DDRRR.419 was used as a 3D query for virtual screening against the ZINC database. In the virtual screening workflow, docking studies (HTVS, SP and XP) were carried out by selecting multiple receptors (PDB ID: 1T69, 1T64, 4LXZ, 4LY1, 3MAX, 2VQQ, 3C10, 1W22). Finally, six compounds were obtained based on high scoring function (dock score -11.2278-10.2222 kcal/mol) and diverse structures. The structure activity correlation was established using virtual screening, docking, energetic based pharmacophore modelling, pharmacophore, atom based 3D QSAR models and their validation. The outcomes of these studies could be further employed for the design of novel HDAC inhibitors for anticancer activity.

The SEE Experience: Edutainment in 3D Virtual Worlds.

ERIC Educational Resources Information Center

Di Blas, Nicoletta; Paolini, Paolo; Hazan, Susan

Shared virtual worlds are innovative applications where several users, represented by Avatars, simultaneously access via Internet a 3D space. Users cooperate through interaction with the environment and with each other, manipulating objects and chatting as they go. Apart from in the well documented online action games industry, now often played…

Multi-Level Adaptation in End-User Development of 3D Virtual Chemistry Experiments

ERIC Educational Resources Information Center

Liu, Chang; Zhong, Ying

2014-01-01

Multi-level adaptation in end-user development (EUD) is an effective way to enable non-technical end users such as educators to gradually introduce more functionality with increasing complexity to 3D virtual learning environments developed by themselves using EUD approaches. Parameterization, integration, and extension are three levels of…

Adaptive 3D Virtual Learning Environments--A Review of the Literature

ERIC Educational Resources Information Center

Scott, Ezequiel; Soria, Alvaro; Campo, Marcelo

2017-01-01

New ways of learning have emerged in the last years by using computers in education. For instance, many Virtual Learning Environments have been widely adopted by educators, obtaining promising outcomes. Recently, these environments have evolved into more advanced ones using 3D technologies and taking into account the individual learner needs and…

Fuzzy rule-based image segmentation in dynamic MR images of the liver

NASA Astrophysics Data System (ADS)

Kobashi, Syoji; Hata, Yutaka; Tokimoto, Yasuhiro; Ishikawa, Makato

2000-06-01

This paper presents a fuzzy rule-based region growing method for segmenting two-dimensional (2-D) and three-dimensional (3- D) magnetic resonance (MR) images. The method is an extension of the conventional region growing method. The proposed method evaluates the growing criteria by using fuzzy inference techniques. The use of the fuzzy if-then rules is appropriate for describing the knowledge of the legions on the MR images. To evaluate the performance of the proposed method, it was applied to artificially generated images. In comparison with the conventional method, the proposed method shows high robustness for noisy images. The method then applied for segmenting the dynamic MR images of the liver. The dynamic MR imaging has been used for diagnosis of hepatocellular carcinoma (HCC), portal hypertension, and so on. Segmenting the liver, portal vein (PV), and inferior vena cava (IVC) can give useful description for the diagnosis, and is a basis work of a pres-surgery planning system and a virtual endoscope. To apply the proposed method, fuzzy if-then rules are derived from the time-density curve of ROIs. In the experimental results, the 2-D reconstructed and 3-D rendered images of the segmented liver, PV, and IVC are shown. The evaluation by a physician shows that the generated images are comparable to the hepatic anatomy, and they would be useful to understanding, diagnosis, and pre-surgery planning.

From Panoramic Photos to a Low-Cost Photogrammetric Workflow for Cultural Heritage 3d Documentation

NASA Astrophysics Data System (ADS)

D'Annibale, E.; Tassetti, A. N.; Malinverni, E. S.

2013-07-01

The research aims to optimize a workflow of architecture documentation: starting from panoramic photos, tackling available instruments and technologies to propose an integrated, quick and low-cost solution of Virtual Architecture. The broader research background shows how to use spherical panoramic images for the architectural metric survey. The input data (oriented panoramic photos), the level of reliability and Image-based Modeling methods constitute an integrated and flexible 3D reconstruction approach: from the professional survey of cultural heritage to its communication in virtual museum. The proposed work results from the integration and implementation of different techniques (Multi-Image Spherical Photogrammetry, Structure from Motion, Imagebased Modeling) with the aim to achieve high metric accuracy and photorealistic performance. Different documentation chances are possible within the proposed workflow: from the virtual navigation of spherical panoramas to complex solutions of simulation and virtual reconstruction. VR tools make for the integration of different technologies and the development of new solutions for virtual navigation. Image-based Modeling techniques allow 3D model reconstruction with photo realistic and high-resolution texture. High resolution of panoramic photo and algorithms of panorama orientation and photogrammetric restitution vouch high accuracy and high-resolution texture. Automated techniques and their following integration are subject of this research. Data, advisably processed and integrated, provide different levels of analysis and virtual reconstruction joining the photogrammetric accuracy to the photorealistic performance of the shaped surfaces. Lastly, a new solution of virtual navigation is tested. Inside the same environment, it proposes the chance to interact with high resolution oriented spherical panorama and 3D reconstructed model at once.

Using Virtual Reality Computer Models to Support Student Understanding of Astronomical Concepts

ERIC Educational Resources Information Center

Barnett, Michael; Yamagata-Lynch, Lisa; Keating, Tom; Barab, Sasha A.; Hay, Kenneth E.

2005-01-01

The purpose of this study was to examine how 3-dimensional (3-D) models of the Solar System supported student development of conceptual understandings of various astronomical phenomena that required a change in frame of reference. In the course described in this study, students worked in teams to design and construct 3-D virtual reality computer…

Surviving sepsis--a 3D integrative educational simulator.

PubMed

Ježek, Filip; Tribula, Martin; Kulhánek, Tomáš; Mateják, Marek; Privitzer, Pavol; Šilar, Jan; Kofránek, Jiří; Lhotská, Lenka

2015-08-01

Computer technology offers greater educational possibilities, notably simulation and virtual reality. This paper presents a technology which serves to integrate multiple modalities, namely 3D virtual reality, node-based simulator, Physiomodel explorer and explanatory physiological simulators employing Modelica language and Unity3D platform. This emerging tool chain should allow the authors to concentrate more on educational content instead of application development. The technology is demonstrated through Surviving sepsis educational scenario, targeted on Microsoft Windows Store platform.

Control of vertical posture while elevating one foot to avoid a real or virtual obstacle.

PubMed

Ida, Hirofumi; Mohapatra, Sambit; Aruin, Alexander

2017-06-01

The purpose of this study is to investigate the control of vertical posture during obstacle avoidance in a real versus a virtual reality (VR) environment. Ten healthy participants stood upright and lifted one leg to avoid colliding with a real obstacle sliding on the floor toward a participant and with its virtual image. Virtual obstacles were delivered by a head mounted display (HMD) or a 3D projector. The acceleration of the foot, center of pressure, and electrical activity of the leg and trunk muscles were measured and analyzed during the time intervals typical for early postural adjustments (EPAs), anticipatory postural adjustments (APAs), and compensatory postural adjustments (CPAs). The results showed that the peak acceleration of foot elevation in the HMD condition decreased significantly when compared with that of the real and 3D projector conditions. Reduced activity of the leg and trunk muscles was seen when dealing with virtual obstacles (HMD and 3D projector) as compared with that seen when dealing with real obstacles. These effects were more pronounced during APAs and CPAs. The onsets of muscle activities in the supporting limb were seen during EPAs and APAs. The observed modulation of muscle activity and altered patterns of movement seen while avoiding a virtual obstacle should be considered when designing virtual rehabilitation protocols.

Vision-based overlay of a virtual object into real scene for designing room interior

NASA Astrophysics Data System (ADS)

Harasaki, Shunsuke; Saito, Hideo

2001-10-01

In this paper, we introduce a geometric registration method for augmented reality (AR) and an application system, interior simulator, in which a virtual (CG) object can be overlaid into a real world space. Interior simulator is developed as an example of an AR application of the proposed method. Using interior simulator, users can visually simulate the location of virtual furniture and articles in the living room so that they can easily design the living room interior without placing real furniture and articles, by viewing from many different locations and orientations in real-time. In our system, two base images of a real world space are captured from two different views for defining a projective coordinate of object 3D space. Then each projective view of a virtual object in the base images are registered interactively. After such coordinate determination, an image sequence of a real world space is captured by hand-held camera with tracking non-metric measured feature points for overlaying a virtual object. Virtual objects can be overlaid onto the image sequence by taking each relationship between the images. With the proposed system, 3D position tracking device, such as magnetic trackers, are not required for the overlay of virtual objects. Experimental results demonstrate that 3D virtual furniture can be overlaid into an image sequence of the scene of a living room nearly at video rate (20 frames per second).

Plot of virtual surgery based on CT medical images

NASA Astrophysics Data System (ADS)

Song, Limei; Zhang, Chunbo

2009-10-01

Although the CT device can give the doctors a series of 2D medical images, it is difficult to give vivid view for the doctors to acknowledge the decrease part. In order to help the doctors to plot the surgery, the virtual surgery system is researched based on the three-dimensional visualization technique. After the disease part of the patient is scanned by the CT device, the 3D whole view will be set up based on the 3D reconstruction module of the system. TCut a part is the usually used function for doctors in the real surgery. A curve will be created on the 3D space; and some points can be added on the curve automatically or manually. The position of the point can change the shape of the cut curves. The curve can be adjusted by controlling the points. If the result of the cut function is not satisfied, all the operation can be cancelled to restart. The flexible virtual surgery gives more convenience to the real surgery. Contrast to the existing medical image process system, the virtual surgery system is added to the system, and the virtual surgery can be plotted for a lot of times, till the doctors have enough confidence to start the real surgery. Because the virtual surgery system can give more 3D information of the disease part, some difficult surgery can be discussed by the expert doctors in different city via internet. It is a useful function to understand the character of the disease part, thus to decrease the surgery risk.

Building a virtual archive using brain architecture and Web 3D to deliver neuropsychopharmacology content over the Internet.

PubMed

Mongeau, R; Casu, M A; Pani, L; Pillolla, G; Lianas, L; Giachetti, A

2008-05-01

The vast amount of heterogeneous data generated in various fields of neurosciences such as neuropsychopharmacology can hardly be classified using traditional databases. We present here the concept of a virtual archive, spatially referenced over a simplified 3D brain map and accessible over the Internet. A simple prototype (available at http://aquatics.crs4.it/neuropsydat3d) has been realized using current Web-based virtual reality standards and technologies. It illustrates how primary literature or summary information can easily be retrieved through hyperlinks mapped onto a 3D schema while navigating through neuroanatomy. Furthermore, 3D navigation and visualization techniques are used to enhance the representation of brain's neurotransmitters, pathways and the involvement of specific brain areas in any particular physiological or behavioral functions. The system proposed shows how the use of a schematic spatial organization of data, widely exploited in other fields (e.g. Geographical Information Systems) can be extremely useful to develop efficient tools for research and teaching in neurosciences.

Web-based interactive 3D visualization as a tool for improved anatomy learning.

PubMed

Petersson, Helge; Sinkvist, David; Wang, Chunliang; Smedby, Orjan

2009-01-01

Despite a long tradition, conventional anatomy education based on dissection is declining. This study tested a new virtual reality (VR) technique for anatomy learning based on virtual contrast injection. The aim was to assess whether students value this new three-dimensional (3D) visualization method as a learning tool and what value they gain from its use in reaching their anatomical learning objectives. Several 3D vascular VR models were created using an interactive segmentation tool based on the "virtual contrast injection" method. This method allows users, with relative ease, to convert computer tomography or magnetic resonance images into vivid 3D VR movies using the OsiriX software equipped with the CMIV CTA plug-in. Once created using the segmentation tool, the image series were exported in Quick Time Virtual Reality (QTVR) format and integrated within a web framework of the Educational Virtual Anatomy (EVA) program. A total of nine QTVR movies were produced encompassing most of the major arteries of the body. These movies were supplemented with associated information, color keys, and notes. The results indicate that, in general, students' attitudes towards the EVA-program were positive when compared with anatomy textbooks, but results were not the same with dissections. Additionally, knowledge tests suggest a potentially beneficial effect on learning.

Accuracy of Three-Dimensional Planning in Surgery-First Orthognathic Surgery: Planning Versus Outcome.

PubMed

Tran, Ngoc Hieu; Tantidhnazet, Syrina; Raocharernporn, Somchart; Kiattavornchareon, Sirichai; Pairuchvej, Verasak; Wongsirichat, Natthamet

2018-05-01

The benefit of computer-assisted planning in orthognathic surgery (OGS) has been extensively documented over the last decade. This study aimed to evaluate the accuracy of three-dimensional (3D) virtual planning in surgery-first OGS. Fifteen patients with skeletal class III malocclusion who underwent bimaxillary OGS with surgery-first approach were included. A composite skull model was reconstructed using data from cone-beam computed tomography and stereolithography from a scanned dental cast. Surgical procedures were simulated using Simplant O&O software, and the virtual plan was transferred to the operation room using 3D-printed splints. Differences of the 3D measurements between the virtual plan and postoperative results were evaluated, and the accuracy was reported using root mean square deviation (RMSD) and the Bland-Altman method. The virtual planning was successfully transferred to surgery. The overall mean linear difference was 0.88 mm (0.79 mm for the maxilla and 1 mm for the mandible), and the overall mean angular difference was 1.16°. The RMSD ranged from 0.86 to 1.46 mm and 1.27° to 1.45°, within the acceptable clinical criteria. In this study, virtual surgical planning and 3D-printed surgical splints facilitated the diagnosis and treatment planning, and offered an accurate outcome in surgery-first OGS.

3D gaze tracking system for NVidia 3D Vision®.

PubMed

Wibirama, Sunu; Hamamoto, Kazuhiko

2013-01-01

Inappropriate parallax setting in stereoscopic content generally causes visual fatigue and visual discomfort. To optimize three dimensional (3D) effects in stereoscopic content by taking into account health issue, understanding how user gazes at 3D direction in virtual space is currently an important research topic. In this paper, we report the study of developing a novel 3D gaze tracking system for Nvidia 3D Vision(®) to be used in desktop stereoscopic display. We suggest an optimized geometric method to accurately measure the position of virtual 3D object. Our experimental result shows that the proposed system achieved better accuracy compared to conventional geometric method by average errors 0.83 cm, 0.87 cm, and 1.06 cm in X, Y, and Z dimensions, respectively.

See-through 3D technology for augmented reality

NASA Astrophysics Data System (ADS)

Lee, Byoungho; Lee, Seungjae; Li, Gang; Jang, Changwon; Hong, Jong-Young

2017-06-01

Augmented reality is recently attracting a lot of attention as one of the most spotlighted next-generation technologies. In order to get toward realization of ideal augmented reality, we need to integrate 3D virtual information into real world. This integration should not be noticed by users blurring the boundary between the virtual and real worlds. Thus, ultimate device for augmented reality can reconstruct and superimpose 3D virtual information on the real world so that they are not distinguishable, which is referred to as see-through 3D technology. Here, we introduce our previous researches to combine see-through displays and 3D technologies using emerging optical combiners: holographic optical elements and index matched optical elements. Holographic optical elements are volume gratings that have angular and wavelength selectivity. Index matched optical elements are partially reflective elements using a compensation element for index matching. Using these optical combiners, we could implement see-through 3D displays based on typical methodologies including integral imaging, digital holographic displays, multi-layer displays, and retinal projection. Some of these methods are expected to be optimized and customized for head-mounted or wearable displays. We conclude with demonstration and analysis of fundamental researches for head-mounted see-through 3D displays.

Lead-oriented synthesis: Investigation of organolithium-mediated routes to 3-D scaffolds and 3-D shape analysis of a virtual lead-like library.

PubMed

Lüthy, Monique; Wheldon, Mary C; Haji-Cheteh, Chehasnah; Atobe, Masakazu; Bond, Paul S; O'Brien, Peter; Hubbard, Roderick E; Fairlamb, Ian J S

2015-06-01

Synthetic routes to six 3-D scaffolds containing piperazine, pyrrolidine and piperidine cores have been developed. The synthetic methodology focused on the use of N-Boc α-lithiation-trapping chemistry. Notably, suitably protected and/or functionalised medicinal chemistry building blocks were synthesised via concise, connective methodology. This represents a rare example of lead-oriented synthesis. A virtual library of 190 compounds was then enumerated from the six scaffolds. Of these, 92 compounds (48%) fit the lead-like criteria of: (i) -1⩽AlogP⩽3; (ii) 14⩽number of heavy atoms⩽26; (iii) total polar surface area⩾50Å(2). The 3-D shapes of the 190 compounds were analysed using a triangular plot of normalised principal moments of inertia (PMI). From this, 46 compounds were identified which had lead-like properties and possessed 3-D shapes in under-represented areas of pharmaceutical space. Thus, the PMI analysis of the 190 member virtual library showed that whilst scaffolds which may appear on paper to be 3-D in shape, only 24% of the compounds actually had 3-D structures in the more interesting areas of 3-D drug space. Copyright © 2015 Elsevier Ltd. All rights reserved.

Training wheelchair navigation in immersive virtual environments for patients with spinal cord injury - end-user input to design an effective system.

PubMed

Nunnerley, Joanne; Gupta, Swati; Snell, Deborah; King, Marcus

2017-05-01

A user-centred design was used to develop and test the feasibility of an immersive 3D virtual reality wheelchair training tool for people with spinal cord injury (SCI). A Wheelchair Training System was designed and modelled using the Oculus Rift headset and a Dynamic Control wheelchair joystick. The system was tested by clinicians and expert wheelchair users with SCI. Data from focus groups and individual interviews were analysed using a general inductive approach to thematic analysis. Four themes emerged: Realistic System, which described the advantages of a realistic virtual environment; a Wheelchair Training System, which described participants' thoughts on the wheelchair training applications; Overcoming Resistance to Technology, the obstacles to introducing technology within the clinical setting; and Working outside the Rehabilitation Bubble which described the protective hospital environment. The Oculus Rift Wheelchair Training System has the potential to provide a virtual rehabilitation setting which could allow wheelchair users to learn valuable community wheelchair use in a safe environment. Nausea appears to be a side effect of the system, which will need to be resolved before this can be a viable clinical tool. Implications for Rehabilitation Immersive virtual reality shows promising benefit for wheelchair training in a rehabilitation setting. Early engagement with consumers can improve product development.

A general method for the derivation of the functional forms of the effective energy terms in coarse-grained energy functions of polymers. II. Backbone-local potentials of coarse-grained O 1 →4 -bonded polyglucose chains

NASA Astrophysics Data System (ADS)

Lubecka, Emilia A.; Liwo, Adam

2017-09-01

Based on the theory of the construction of coarse-grained force fields for polymer chains described in our recent work [A. K. Sieradzan et al., J. Chem. Phys. 146, 124106 (2017)], in this work effective coarse-grained potentials, to be used in the SUGRES-1P model of polysaccharides that is being developed in our laboratory, have been determined for the O ⋯O ⋯O virtual-bond angles (θ ) and for the dihedral angles for rotation about the O ⋯O virtual bonds (γ ) of 1 → 4 -linked glucosyl polysaccharides, for all possible combinations of [α ,β ]-[d,l]-glucose. The potentials of mean force corresponding to the virtual-bond angles and the virtual-bond dihedral angles were calculated from the free-energy surfaces of [α ,β ]-[d,l]-glucose pairs, determined by umbrella-sampling molecular-dynamics simulations with the AMBER12 force field, or combinations of the surfaces of two pairs sharing the overlapping residue, respectively, by integrating the respective Boltzmann factor over the dihedral angles λ for the rotation of the sugar units about the O ⋯O virtual bonds. Analytical expressions were subsequently fitted to the potentials of mean force. The virtual-bond-torsional potentials depend on both virtual-bond-dihedral angles and virtual-bond angles. The virtual-bond-angle potentials contain a single minimum at about θ =14 0° for all pairs except β -d-[α ,β ] -l-glucose, where the global minimum is shifted to θ =150° and a secondary minimum appears at θ =90°. The torsional potentials favor small negative γ angles for the α -d-glucose and extended negative angles γ for the β -d-glucose chains, as observed in the experimental structures of starch and cellulose, respectively. It was also demonstrated that the approximate expression derived based on Kubo's cluster-cumulant theory, whose coefficients depend on the identity of the disugar units comprising a trisugar unit that defines a torsional potential, fits simultaneously all torsional potentials very well, thus reducing the number of parameters significantly.

Faster acquisition of laparoscopic skills in virtual reality with haptic feedback and 3D vision.

PubMed

Hagelsteen, Kristine; Langegård, Anders; Lantz, Adam; Ekelund, Mikael; Anderberg, Magnus; Bergenfelz, Anders

2017-10-01

The study investigated whether 3D vision and haptic feedback in combination in a virtual reality environment leads to more efficient learning of laparoscopic skills in novices. Twenty novices were allocated to two groups. All completed a training course in the LapSim ® virtual reality trainer consisting of four tasks: 'instrument navigation', 'grasping', 'fine dissection' and 'suturing'. The study group performed with haptic feedback and 3D vision and the control group without. Before and after the LapSim ® course, the participants' metrics were recorded when tying a laparoscopic knot in the 2D video box trainer Simball ® Box. The study group completed the training course in 146 (100-291) minutes compared to 215 (175-489) minutes in the control group (p = .002). The number of attempts to reach proficiency was significantly lower. The study group had significantly faster learning of skills in three out of four individual tasks; instrument navigation, grasping and suturing. Using the Simball ® Box, no difference in laparoscopic knot tying after the LapSim ® course was noted when comparing the groups. Laparoscopic training in virtual reality with 3D vision and haptic feedback made training more time efficient and did not negatively affect later video box-performance in 2D. [Formula: see text].

Image calibration and registration in cone-beam computed tomogram for measuring the accuracy of computer-aided implant surgery

NASA Astrophysics Data System (ADS)

Lam, Walter Y. H.; Ngan, Henry Y. T.; Wat, Peter Y. P.; Luk, Henry W. K.; Goto, Tazuko K.; Pow, Edmond H. N.

2015-02-01

Medical radiography is the use of radiation to "see through" a human body without breaching its integrity (surface). With computed tomography (CT)/cone beam computed tomography (CBCT), three-dimensional (3D) imaging can be produced. These imagings not only facilitate disease diagnosis but also enable computer-aided surgical planning/navigation. In dentistry, the common method for transfer of the virtual surgical planning to the patient (reality) is the use of surgical stent either with a preloaded planning (static) like a channel or a real time surgical navigation (dynamic) after registration with fiducial markers (RF). This paper describes using the corner of a cube as a radiopaque fiducial marker on an acrylic (plastic) stent, this RF allows robust calibration and registration of Cartesian (x, y, z)- coordinates for linking up the patient (reality) and the imaging (virtuality) and hence the surgical planning can be transferred in either static or dynamic way. The accuracy of computer-aided implant surgery was measured with reference to coordinates. In our preliminary model surgery, a dental implant was planned virtually and placed with preloaded surgical guide. The deviation of the placed implant apex from the planning was x=+0.56mm [more right], y=- 0.05mm [deeper], z=-0.26mm [more lingual]) which was within clinically 2mm safety range. For comparison with the virtual planning, the physically placed implant was CT/CBCT scanned and errors may be introduced. The difference of the actual implant apex to the virtual apex was x=0.00mm, y=+0.21mm [shallower], z=-1.35mm [more lingual] and this should be brought in mind when interpret the results.

Use of cues in virtual reality depends on visual feedback.

PubMed

Fulvio, Jacqueline M; Rokers, Bas

2017-11-22

3D motion perception is of central importance to daily life. However, when tested in laboratory settings, sensitivity to 3D motion signals is found to be poor, leading to the view that heuristics and prior assumptions are critical for 3D motion perception. Here we explore an alternative: sensitivity to 3D motion signals is context-dependent and must be learned based on explicit visual feedback in novel environments. The need for action-contingent visual feedback is well-established in the developmental literature. For example, young kittens that are passively moved through an environment, but unable to move through it themselves, fail to develop accurate depth perception. We find that these principles also obtain in adult human perception. Observers that do not experience visual consequences of their actions fail to develop accurate 3D motion perception in a virtual reality environment, even after prolonged exposure. By contrast, observers that experience the consequences of their actions improve performance based on available sensory cues to 3D motion. Specifically, we find that observers learn to exploit the small motion parallax cues provided by head jitter. Our findings advance understanding of human 3D motion processing and form a foundation for future study of perception in virtual and natural 3D environments.

Evaluation of a low-cost 3D sound system for immersive virtual reality training systems.

PubMed

Doerr, Kai-Uwe; Rademacher, Holger; Huesgen, Silke; Kubbat, Wolfgang

2007-01-01

Since Head Mounted Displays (HMD), datagloves, tracking systems, and powerful computer graphics resources are nowadays in an affordable price range, the usage of PC-based "Virtual Training Systems" becomes very attractive. However, due to the limited field of view of HMD devices, additional modalities have to be provided to benefit from 3D environments. A 3D sound simulation can improve the capabilities of VR systems dramatically. Unfortunately, realistic 3D sound simulations are expensive and demand a tremendous amount of computational power to calculate reverberation, occlusion, and obstruction effects. To use 3D sound in a PC-based training system as a way to direct and guide trainees to observe specific events in 3D space, a cheaper alternative has to be provided, so that a broader range of applications can take advantage of this modality. To address this issue, we focus in this paper on the evaluation of a low-cost 3D sound simulation that is capable of providing traceable 3D sound events. We describe our experimental system setup using conventional stereo headsets in combination with a tracked HMD device and present our results with regard to precision, speed, and used signal types for localizing simulated sound events in a virtual training environment.

Three-dimensional virtual planning in orthognathic surgery enhances the accuracy of soft tissue prediction.

PubMed

Van Hemelen, Geert; Van Genechten, Maarten; Renier, Lieven; Desmedt, Maria; Verbruggen, Elric; Nadjmi, Nasser

2015-07-01

Throughout the history of computing, shortening the gap between the physical and digital world behind the screen has always been strived for. Recent advances in three-dimensional (3D) virtual surgery programs have reduced this gap significantly. Although 3D assisted surgery is now widely available for orthognathic surgery, one might still argue whether a 3D virtual planning approach is a better alternative to a conventional two-dimensional (2D) planning technique. The purpose of this study was to compare the accuracy of a traditional 2D technique and a 3D computer-aided prediction method. A double blind randomised prospective study was performed to compare the prediction accuracy of a traditional 2D planning technique versus a 3D computer-aided planning approach. The accuracy of the hard and soft tissue profile predictions using both planning methods was investigated. There was a statistically significant difference between 2D and 3D soft tissue planning (p < 0.05). The statistically significant difference found between 2D and 3D planning and the actual soft tissue outcome was not confirmed by a statistically significant difference between methods. The 3D planning approach provides more accurate soft tissue planning. However, the 2D orthognathic planning is comparable to 3D planning when it comes to hard tissue planning. This study provides relevant results for choosing between 3D and 2D planning in clinical practice. Copyright © 2015 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Image-Based Virtual Tours and 3d Modeling of Past and Current Ages for the Enhancement of Archaeological Parks: the Visualversilia 3d Project

NASA Astrophysics Data System (ADS)

Castagnetti, C.; Giannini, M.; Rivola, R.

2017-05-01

The research project VisualVersilia 3D aims at offering a new way to promote the territory and its heritage by matching the traditional reading of the document and the potential use of modern communication technologies for the cultural tourism. Recently, the research on the use of new technologies applied to cultural heritage have turned their attention mainly to technologies to reconstruct and narrate the complexity of the territory and its heritage, including 3D scanning, 3D printing and augmented reality. Some museums and archaeological sites already exploit the potential of digital tools to preserve and spread their heritage but interactive services involving tourists in an immersive and more modern experience are still rare. The innovation of the project consists in the development of a methodology for documenting current and past historical ages and integrating their 3D visualizations with rendering capable of returning an immersive virtual reality for a successful enhancement of the heritage. The project implements the methodology in the archaeological complex of Massaciuccoli, one of the best preserved roman site of the Versilia Area (Tuscany, Italy). The activities of the project briefly consist in developing: 1. the virtual tour of the site in its current configuration on the basis of spherical images then enhanced by texts, graphics and audio guides in order to enable both an immersive and remote tourist experience; 2. 3D reconstruction of the evidences and buildings in their current condition for documentation and conservation purposes on the basis of a complete metric survey carried out through laser scanning; 3. 3D virtual reconstructions through the main historical periods on the basis of historical investigation and the analysis of data acquired.

Design of 3D simulation engine for oilfield safety training

NASA Astrophysics Data System (ADS)

Li, Hua-Ming; Kang, Bao-Sheng

2015-03-01

Aiming at the demand for rapid custom development of 3D simulation system for oilfield safety training, this paper designs and implements a 3D simulation engine based on script-driven method, multi-layer structure, pre-defined entity objects and high-level tools such as scene editor, script editor, program loader. A scripting language been defined to control the system's progress, events and operating results. Training teacher can use this engine to edit 3D virtual scenes, set the properties of entity objects, define the logic script of task, and produce a 3D simulation training system without any skills of programming. Through expanding entity class, this engine can be quickly applied to other virtual training areas.

Comparison of Actual Surgical Outcomes and 3D Surgical Simulations

PubMed Central

Tucker, Scott; Cevidanes, Lucia; Styner, Martin; Kim, Hyungmin; Reyes, Mauricio; Proffit, William; Turvey, Timothy

2009-01-01

Purpose The advent of imaging software programs have proved to be useful for diagnosis, treatment planning, and outcome measurement, but precision of 3D surgical simulation still needs to be tested. This study was conducted to determine if the virtual surgery performed on 3D models constructed from Cone-beam CT (CBCT) can correctly simulate the actual surgical outcome and to validate the ability of this emerging technology to recreate the orthognathic surgery hard tissue movements in 3 translational and 3 rotational planes of space. Methods Construction of pre- and post-surgery 3D models from CBCTs of 14 patients who had combined maxillary advancement and mandibular setback surgery and 6 patients who had one-piece maxillary advancement surgery was performed. The post-surgery and virtually simulated surgery 3D models were registered at the cranial base to quantify differences between simulated and actual surgery models. Hotelling T-test were used to assess the differences between simulated and actual surgical outcomes. Results For all anatomic regions of interest, there was no statistically significant difference between the simulated and the actual surgical models. The right lateral ramus was the only region that showed a statistically significant, but small difference when comparing two- and one-jaw surgeries. Conclusions Virtual surgical methods were reliably reproduced, oral surgery residents could benefit from virtual surgical training, and computer simulation has the potential to increase predictability in the operating room. PMID:20591553

Virtual screening and rational drug design method using structure generation system based on 3D-QSAR and docking.

PubMed

Chen, H F; Dong, X C; Zen, B S; Gao, K; Yuan, S G; Panaye, A; Doucet, J P; Fan, B T

2003-08-01

An efficient virtual and rational drug design method is presented. It combines virtual bioactive compound generation with 3D-QSAR model and docking. Using this method, it is possible to generate a lot of highly diverse molecules and find virtual active lead compounds. The method was validated by the study of a set of anti-tumor drugs. With the constraints of pharmacophore obtained by DISCO implemented in SYBYL 6.8, 97 virtual bioactive compounds were generated, and their anti-tumor activities were predicted by CoMFA. Eight structures with high activity were selected and screened by the 3D-QSAR model. The most active generated structure was further investigated by modifying its structure in order to increase the activity. A comparative docking study with telomeric receptor was carried out, and the results showed that the generated structures could form more stable complexes with receptor than the reference compound selected from experimental data. This investigation showed that the proposed method was a feasible way for rational drug design with high screening efficiency.

Design and Implementation of a Self-Directed Stereochemistry Lesson Using Embedded Virtual Three-Dimensional Images in a Portable Document Format

ERIC Educational Resources Information Center

Cody, Jeremy A.; Craig, Paul A.; Loudermilk, Adam D.; Yacci, Paul M.; Frisco, Sarah L.; Milillo, Jennifer R.

2012-01-01

A novel stereochemistry lesson was prepared that incorporated both handheld molecular models and embedded virtual three-dimensional (3D) images. The images are fully interactive and eye-catching for the students; methods for preparing 3D molecular images in Adobe Acrobat are included. The lesson was designed and implemented to showcase the 3D…

Collaborative visual analytics of radio surveys in the Big Data era

NASA Astrophysics Data System (ADS)

Vohl, Dany; Fluke, Christopher J.; Hassan, Amr H.; Barnes, David G.; Kilborn, Virginia A.

2017-06-01

Radio survey datasets comprise an increasing number of individual observations stored as sets of multidimensional data. In large survey projects, astronomers commonly face limitations regarding: 1) interactive visual analytics of sufficiently large subsets of data; 2) synchronous and asynchronous collaboration; and 3) documentation of the discovery workflow. To support collaborative data inquiry, we present encube, a large-scale comparative visual analytics framework. encube can utilise advanced visualization environments such as the CAVE2 (a hybrid 2D and 3D virtual reality environment powered with a 100 Tflop/s GPU-based supercomputer and 84 million pixels) for collaborative analysis of large subsets of data from radio surveys. It can also run on standard desktops, providing a capable visual analytics experience across the display ecology. encube is composed of four primary units enabling compute-intensive processing, advanced visualisation, dynamic interaction, parallel data query, along with data management. Its modularity will make it simple to incorporate astronomical analysis packages and Virtual Observatory capabilities developed within our community. We discuss how encube builds a bridge between high-end display systems (such as CAVE2) and the classical desktop, preserving all traces of the work completed on either platform - allowing the research process to continue wherever you are.

Evaluating the Usability of Pinchigator, a system for Navigating Virtual Worlds using Pinch Gloves

NASA Technical Reports Server (NTRS)

Hamilton, George S.; Brookman, Stephen; Dumas, Joseph D. II; Tilghman, Neal

2003-01-01

Appropriate design of two dimensional user interfaces (2D U/I) utilizing the well known WIMP (Window, Icon, Menu, Pointing device) environment for computer software is well studied and guidance can be found in several standards. Three-dimensional U/I design is not nearly so mature as 2D U/I, and standards bodies have not reached consensus on what makes a usable interface. This is especially true when the tools for interacting with the virtual environment may include stereo viewing, real time trackers and pinch gloves instead of just a mouse & keyboard. Over the last several years the authors have created a 3D U/I system dubbed Pinchigator for navigating virtual worlds based on the dVise dV/Mockup visualization software, Fakespace Pinch Gloves and Pohlemus trackers. The current work is to test the usability of the system on several virtual worlds, suggest improvements to increase Pinchigator s usability, and then to generalize about what was learned and how those lessons might be applied to improve other 3D U/I systems.

Model Manipulation and Learning: Fostering Representational Competence with Virtual and Concrete Models

ERIC Educational Resources Information Center

Stull, Andrew T.; Hegarty, Mary

2016-01-01

This study investigated the development of representational competence among organic chemistry students by using 3D (concrete and virtual) models as aids for teaching students to translate between multiple 2D diagrams. In 2 experiments, students translated between different diagrams of molecules and received verbal feedback in 1 of the following 3…

SciEthics Interactive: Science and Ethics Learning in a Virtual Environment

ERIC Educational Resources Information Center

Nadolny, Larysa; Woolfrey, Joan; Pierlott, Matthew; Kahn, Seth

2013-01-01

Learning in immersive 3D environments allows students to collaborate, build, and interact with difficult course concepts. This case study examines the design and development of the TransGen Island within the SciEthics Interactive project, a National Science Foundation-funded, 3D virtual world emphasizing learning science content in the context of…

From Vesalius to Virtual Reality: How Embodied Cognition Facilitates the Visualization of Anatomy

ERIC Educational Resources Information Center

Jang, Susan

2010-01-01

This study examines the facilitative effects of embodiment of a complex internal anatomical structure through three-dimensional ("3-D") interactivity in a virtual reality ("VR") program. Since Shepard and Metzler's influential 1971 study, it has been known that 3-D objects (e.g., multiple-armed cube or external body parts) are visually and…

ICCE/ICCAI 2000 Full & Short Papers (Virtual Reality in Education).

ERIC Educational Resources Information Center

2000

This document contains the full text of the following full and short papers on virtual reality in education from ICCE/ICCAI 2000 (International Conference on Computers in Education/International Conference on Computer-Assisted Instruction): (1) "A CAL System for Appreciation of 3D Shapes by Surface Development (C3D-SD)" (Stephen C. F. Chan, Andy…

Exploring 3-D Virtual Reality Technology for Spatial Ability and Chemistry Achievement

ERIC Educational Resources Information Center

Merchant, Z.; Goetz, E. T.; Keeney-Kennicutt, W.; Cifuentes, L.; Kwok, O.; Davis, T. J.

2013-01-01

We investigated the potential of Second Life® (SL), a three-dimensional (3-D) virtual world, to enhance undergraduate students' learning of a vital chemistry concept. A quasi-experimental pre-posttest control group design was used to conduct the study. A total of 387 participants completed three assignment activities either in SL or using…

Web-Based Interactive 3D Visualization as a Tool for Improved Anatomy Learning

ERIC Educational Resources Information Center

Petersson, Helge; Sinkvist, David; Wang, Chunliang; Smedby, Orjan

2009-01-01

Despite a long tradition, conventional anatomy education based on dissection is declining. This study tested a new virtual reality (VR) technique for anatomy learning based on virtual contrast injection. The aim was to assess whether students value this new three-dimensional (3D) visualization method as a learning tool and what value they gain…

Teaching Digital Natives: 3-D Virtual Science Lab in the Middle School Science Classroom

ERIC Educational Resources Information Center

Franklin, Teresa J.

2008-01-01

This paper presents the development of a 3-D virtual environment in Second Life for the delivery of standards-based science content for middle school students in the rural Appalachian region of Southeast Ohio. A mixed method approach in which quantitative results of improved student learning and qualitative observations of implementation within…

Socialisation for Learning at a Distance in a 3-D Multi-User Virtual Environment

ERIC Educational Resources Information Center

Edirisingha, Palitha; Nie, Ming; Pluciennik, Mark; Young, Ruth

2009-01-01

This paper reports findings of a pilot study that examined the pedagogical potential of "Second Life" (SL), a popular three-dimensional multi-user virtual environment (3-D MUVE) developed by the Linden Lab. The study is part of a 1-year research and development project titled "Modelling of Secondlife Environments"…

Web GIS in practice X: a Microsoft Kinect natural user interface for Google Earth navigation

PubMed Central

2011-01-01

This paper covers the use of depth sensors such as Microsoft Kinect and ASUS Xtion to provide a natural user interface (NUI) for controlling 3-D (three-dimensional) virtual globes such as Google Earth (including its Street View mode), Bing Maps 3D, and NASA World Wind. The paper introduces the Microsoft Kinect device, briefly describing how it works (the underlying technology by PrimeSense), as well as its market uptake and application potential beyond its original intended purpose as a home entertainment and video game controller. The different software drivers available for connecting the Kinect device to a PC (Personal Computer) are also covered, and their comparative pros and cons briefly discussed. We survey a number of approaches and application examples for controlling 3-D virtual globes using the Kinect sensor, then describe Kinoogle, a Kinect interface for natural interaction with Google Earth, developed by students at Texas A&M University. Readers interested in trying out the application on their own hardware can download a Zip archive (included with the manuscript as additional files 1, 2, &3) that contains a 'Kinnogle installation package for Windows PCs'. Finally, we discuss some usability aspects of Kinoogle and similar NUIs for controlling 3-D virtual globes (including possible future improvements), and propose a number of unique, practical 'use scenarios' where such NUIs could prove useful in navigating a 3-D virtual globe, compared to conventional mouse/3-D mouse and keyboard-based interfaces. PMID:21791054

Web GIS in practice X: a Microsoft Kinect natural user interface for Google Earth navigation.

PubMed

Boulos, Maged N Kamel; Blanchard, Bryan J; Walker, Cory; Montero, Julio; Tripathy, Aalap; Gutierrez-Osuna, Ricardo

2011-07-26

This paper covers the use of depth sensors such as Microsoft Kinect and ASUS Xtion to provide a natural user interface (NUI) for controlling 3-D (three-dimensional) virtual globes such as Google Earth (including its Street View mode), Bing Maps 3D, and NASA World Wind. The paper introduces the Microsoft Kinect device, briefly describing how it works (the underlying technology by PrimeSense), as well as its market uptake and application potential beyond its original intended purpose as a home entertainment and video game controller. The different software drivers available for connecting the Kinect device to a PC (Personal Computer) are also covered, and their comparative pros and cons briefly discussed. We survey a number of approaches and application examples for controlling 3-D virtual globes using the Kinect sensor, then describe Kinoogle, a Kinect interface for natural interaction with Google Earth, developed by students at Texas A&M University. Readers interested in trying out the application on their own hardware can download a Zip archive (included with the manuscript as additional files 1, 2, &3) that contains a 'Kinnogle installation package for Windows PCs'. Finally, we discuss some usability aspects of Kinoogle and similar NUIs for controlling 3-D virtual globes (including possible future improvements), and propose a number of unique, practical 'use scenarios' where such NUIs could prove useful in navigating a 3-D virtual globe, compared to conventional mouse/3-D mouse and keyboard-based interfaces.

Simultaneous neural and movement recording in large-scale immersive virtual environments.

PubMed

Snider, Joseph; Plank, Markus; Lee, Dongpyo; Poizner, Howard

2013-10-01

Virtual reality (VR) allows precise control and manipulation of rich, dynamic stimuli that, when coupled with on-line motion capture and neural monitoring, can provide a powerful means both of understanding brain behavioral relations in the high dimensional world and of assessing and treating a variety of neural disorders. Here we present a system that combines state-of-the-art, fully immersive, 3D, multi-modal VR with temporally aligned electroencephalographic (EEG) recordings. The VR system is dynamic and interactive across visual, auditory, and haptic interactions, providing sight, sound, touch, and force. Crucially, it does so with simultaneous EEG recordings while subjects actively move about a 20 × 20 ft² space. The overall end-to-end latency between real movement and its simulated movement in the VR is approximately 40 ms. Spatial precision of the various devices is on the order of millimeters. The temporal alignment with the neural recordings is accurate to within approximately 1 ms. This powerful combination of systems opens up a new window into brain-behavioral relations and a new means of assessment and rehabilitation of individuals with motor and other disorders.

Three-dimensional-printed gas dynamic virtual nozzles for x-ray laser sample delivery

PubMed Central

Nelson, Garrett; Kirian, Richard A.; Weierstall, Uwe; Zatsepin, Nadia A.; Faragó, Tomáš; Baumbach, Tilo; Wilde, Fabian; Niesler, Fabian B. P.; Zimmer, Benjamin; Ishigami, Izumi; Hikita, Masahide; Bajt, Saša; Yeh, Syun-Ru; Rousseau, Denis L.; Chapman, Henry N.; Spence, John C. H.; Heymann, Michael

2016-01-01

Reliable sample delivery is essential to biological imaging using X-ray Free Electron Lasers (XFELs). Continuous injection using the Gas Dynamic Virtual Nozzle (GDVN) has proven valuable, particularly for time-resolved studies. However, many important aspects of GDVN functionality have yet to be thoroughly understood and/or refined due to fabrication limitations. We report the application of 2-photon polymerization as a form of high-resolution 3D printing to fabricate high-fidelity GDVNs with submicron resolution. This technique allows rapid prototyping of a wide range of different types of nozzles from standard CAD drawings and optimization of crucial dimensions for optimal performance. Three nozzles were tested with pure water to determine general nozzle performance and reproducibility, with nearly reproducible off-axis jetting being the result. X-ray tomography and index matching were successfully used to evaluate the interior nozzle structures and identify the cause of off-axis jetting. Subsequent refinements to fabrication resulted in straight jetting. A performance test of printed nozzles at an XFEL provided high quality femtosecond diffraction patterns. PMID:27410079

Formalizing and Promoting Collaboration in 3D Virtual Environments - A Blueprint for the Creation of Group Interaction Patterns

NASA Astrophysics Data System (ADS)

Schmeil, Andreas; Eppler, Martin J.

Despite the fact that virtual worlds and other types of multi-user 3D collaboration spaces have long been subjects of research and of application experiences, it still remains unclear how to best benefit from meeting with colleagues and peers in a virtual environment with the aim of working together. Making use of the potential of virtual embodiment, i.e. being immersed in a space as a personal avatar, allows for innovative new forms of collaboration. In this paper, we present a framework that serves as a systematic formalization of collaboration elements in virtual environments. The framework is based on the semiotic distinctions among pragmatic, semantic and syntactic perspectives. It serves as a blueprint to guide users in designing, implementing, and executing virtual collaboration patterns tailored to their needs. We present two team and two community collaboration pattern examples as a result of the application of the framework: Virtual Meeting, Virtual Design Studio, Spatial Group Configuration, and Virtual Knowledge Fair. In conclusion, we also point out future research directions for this emerging domain.

Stereoscopic vascular models of the head and neck: A computed tomography angiography visualization.

PubMed

Cui, Dongmei; Lynch, James C; Smith, Andrew D; Wilson, Timothy D; Lehman, Michael N

2016-01-01

Computer-assisted 3D models are used in some medical and allied health science schools; however, they are often limited to online use and 2D flat screen-based imaging. Few schools take advantage of 3D stereoscopic learning tools in anatomy education and clinically relevant anatomical variations when teaching anatomy. A new approach to teaching anatomy includes use of computed tomography angiography (CTA) images of the head and neck to create clinically relevant 3D stereoscopic virtual models. These high resolution images of the arteries can be used in unique and innovative ways to create 3D virtual models of the vasculature as a tool for teaching anatomy. Blood vessel 3D models are presented stereoscopically in a virtual reality environment, can be rotated 360° in all axes, and magnified according to need. In addition, flexible views of internal structures are possible. Images are displayed in a stereoscopic mode, and students view images in a small theater-like classroom while wearing polarized 3D glasses. Reconstructed 3D models enable students to visualize vascular structures with clinically relevant anatomical variations in the head and neck and appreciate spatial relationships among the blood vessels, the skull and the skin. © 2015 American Association of Anatomists.

An integrated pipeline to create and experience compelling scenarios in virtual reality

NASA Astrophysics Data System (ADS)

Springer, Jan P.; Neumann, Carsten; Reiners, Dirk; Cruz-Neira, Carolina

2011-03-01

One of the main barriers to create and use compelling scenarios in virtual reality is the complexity and time-consuming efforts for modeling, element integration, and the software development to properly display and interact with the content in the available systems. Still today, most virtual reality applications are tedious to create and they are hard-wired to the specific display and interaction system available to the developers when creating the application. Furthermore, it is not possible to alter the content or the dynamics of the content once the application has been created. We present our research on designing a software pipeline that enables the creation of compelling scenarios with a fair degree of visual and interaction complexity in a semi-automated way. Specifically, we are targeting drivable urban scenarios, ranging from large cities to sparsely populated rural areas that incorporate both static components (e. g., houses, trees) and dynamic components (e. g., people, vehicles) as well as events, such as explosions or ambient noise. Our pipeline has four basic components. First, an environment designer, where users sketch the overall layout of the scenario, and an automated method constructs the 3D environment from the information in the sketch. Second, a scenario editor used for authoring the complete scenario, incorporate the dynamic elements and events, fine tune the automatically generated environment, define the execution conditions of the scenario, and set up any data gathering that may be necessary during the execution of the scenario. Third, a run-time environment for different virtual-reality systems provides users with the interactive experience as designed with the designer and the editor. And fourth, a bi-directional monitoring system that allows for capturing and modification of information from the virtual environment. One of the interesting capabilities of our pipeline is that scenarios can be built and modified on-the-fly as they are being presented in the virtual-reality systems. Users can quickly prototype the basic scene using the designer and the editor on a control workstation. More elements can then be introduced into the scene from both the editor and the virtual-reality display. In this manner, users are able to gradually increase the complexity of the scenario with immediate feedback. The main use of this pipeline is the rapid development of scenarios for human-factors studies. However, it is applicable in a much more general context.

Low Q2 jet production at HERA and virtual photon structure

NASA Astrophysics Data System (ADS)

H1 Collaboration; Adloff, C.; Aid, S.; Anderson, M.; Andreev, V.; Andrieu, B.; Arkadov, V.; Arndt, C.; Ayyaz, I.; Babaev, A.; Bähr, J.; Bán, J.; Baranov, P.; Barrelet, E.; Barschke, R.; Bartel, W.; Bassler, U.; Beck, M.; Behrend, H.-J.; Beier, C.; Belousov, A.; Berger, Ch.; Bernardi, G.; Bertrand-Coremans, G.; Beyer, R.; Biddulph, P.; Bizot, J. C.; Borras, K.; Botterweck, F.; Boudry, V.; Bourov, S.; Braemer, A.; Braunschweig, W.; Brisson, V.; Brown, D. P.; Brückner, W.; Bruel, P.; Bruncko, D.; Brune, C.; Bürger, J.; Büsser, F. W.; Buniatian, A.; Burke, S.; Buschhorn, G.; Calvet, D.; Campbell, A. J.; Carli, T.; Charlet, M.; Clarke, D.; Clerbaux, B.; Cocks, S.; Contreras, J. G.; Cormack, C.; Coughlan, J. A.; Cousinou, M.-C.; Cox, B. E.; Cozzika, G.; Cussans, D. G.; Cvach, J.; Dagoret, S.; Dainton, J. B.; Dau, W. D.; Daum, K.; David, M.; de Roeck, A.; de Wolf, E. A.; Delcourt, B.; Dirkmann, M.; Dixon, P.; Dlugosz, W.; Donovan, K. T.; Dowell, J. D.; Droutskoi, A.; Ebert, J.; Ebert, T. R.; Eckerlin, G.; Efremenko, V.; Egli, S.; Eichler, R.; Eisele, F.; Eisenhandler, E.; Elsen, E.; Erdmann, M.; Fahr, A. B.; Favart, L.; Fedotov, A.; Felst, R.; Feltesse, J.; Ferencei, J.; Ferrarotto, F.; Flamm, K.; Fleischer, M.; Flieser, M.; Flügge, G.; Fomenko, A.; Formánek, J.; Foster, J. M.; Franke, G.; Gabathuler, E.; Gabathuler, K.; Gaede, F.; Garvey, J.; Gayler, J.; Gebauer, M.; Gerhards, R.; Glazov, A.; Goerlich, L.; Gogitidze, N.; Goldberg, M.; Gonzalez-Pineiro, B.; Gorelov, I.; Grab, C.; Grässler, H.; Greenshaw, T.; Griffiths, R. K.; Grindhammer, G.; Gruber, A.; Gruber, C.; Hadig, T.; Haidt, D.; Hajduk, L.; Haller, T.; Hampel, M.; Haynes, W. J.; Heinemann, B.; Heinzelmann, G.; Henderson, R. C. W.; Hengstmann, S.; Henschel, H.; Herynek, I.; Hess, M. F.; Hewitt, K.; Hiller, K. H.; Hilton, C. D.; Hladký, J.; Höppner, M.; Hoffmann, D.; Holtom, T.; Horisberger, R.; Hudgson, V. L.; Hütte, M.; Ibbotson, M.; Isolarş Sever, Ç.; Itterbeck, H.; Jacquet, M.; Jaffre, M.; Janoth, J.; Jansen, D. M.; Jönsson, L.; Johnson, D. P.; Jung, H.; Kalmus, P. I. P.; Kander, M.; Kant, D.; Kathage, U.; Katzy, J.; Kaufmann, H. H.; Kaufmann, O.; Kausch, M.; Kazarian, S.; Kenyon, I. R.; Kermiche, S.; Keuker, C.; Kiesling, C.; Klein, M.; Kleinwort, C.; Knies, G.; Köhne, J. H.; Kolanoski, H.; Kolya, S. D.; Korbel, V.; Kostka, P.; Kotelnikov, S. K.; Krämerkämper, T.; Krasny, M. W.; Krehbiel, H.; Krücker, D.; Küpper, A.; Küster, H.; Kuhlen, M.; Kurča, T.; Laforge, B.; Lahmann, R.; Landon, M. P. J.; Lange, W.; Langenegger, U.; Lebedev, A.; Lehner, F.; Lemaitre, V.; Levonian, S.; Lindstroem, M.; Lipinski, J.; List, B.; Lobo, G.; Lopez, G. C.; Lubimov, V.; Lüke, D.; Lytkin, L.; Magnussen, N.; Mahlke-Krüger, H.; Malinovski, E.; Maraček, R.; Marage, P.; Marks, J.; Marshall, R.; Martens, J.; Martin, G.; Martin, R.; Martyn, H.-U.; Martyniak, J.; Mavroidis, T.; Maxfield, S. J.; McMahon, S. J.; Mehta, A.; Meier, K.; Merkel, P.; Metlica, F.; Meyer, A.; Meyer, A.; Meyer, H.; Meyer, J.; Meyer, P.-O.; Migliori, A.; Mikocki, S.; Milstead, D.; Moeck, J.; Moreau, F.; Morris, J. V.; Mroczko, E.; Müller, D.; Müller, K.; Murín, P.; Nagovizin, V.; Nahnhauer, R.; Naroska, B.; Naumann, Th.; Négri, I.; Newman, P. R.; Newton, D.; Nguyen, H. K.; Nicholls, T. C.; Niebergall, F.; Niebuhr, C.; Niedzballa, Ch.; Niggli, H.; Nowak, G.; Nunnemann, T.; Oberlack, H.; Olsson, J. E.; Ozerov, D.; Palmen, P.; Panaro, E.; Panitch, A.; Pascaud, C.; Passaggio, S.; Patel, G. D.; Pawletta, H.; Peppel, E.; Perez, E.; Phillips, J. P.; Pieuchot, A.; Pitzl, D.; Pöschl, R.; Pope, G.; Povh, B.; Rabbertz, K.; Reimer, P.; Rick, H.; Riess, S.; Rizvi, E.; Robmann, P.; Roosen, R.; Rosenbauer, K.; Rostovtsev, A.; Rouse, F.; Royon, C.; Rüter, K.; Rusakov, S.; Rybicki, K.; Sankey, D. P. C.; Schacht, P.; Scheins, J.; Schiek, S.; Schleif, S.; Schleper, P.; von Schlippe, W.; Schmidt, D.; Schmidt, G.; Schoeffel, L.; Schöning, A.; Schröder, V.; Schuhmann, E.; Schultz-Coulon, H.-C.; Schwab, B.; Sefkow, F.; Semenov, A.; Shekelyan, V.; Sheviakov, I.; Shtarkov, L. N.; Siegmon, G.; Siewert, U.; Sirois, Y.; Skillicorn, I. O.; Sloan, T.; Smirnov, P.; Smith, M.; Solochenko, V.; Soloviev, Y.; Specka, A.; Spiekermann, J.; Spielman, S.; Spitzer, H.; Squinabol, F.; Steffen, P.; Steinberg, R.; Steinhart, J.; Stella, B.; Stellberger, A.; Stiewe, J.; Stolze, K.; Straumann, U.; Struczinski, W.; Sutton, J. P.; Swart, M.; Tapprogge, S.; Taševský, M.; Tchernyshov, V.; Tchetchelnitski, S.; Theissen, J.; Thompson, G.; Thompson, P. D.; Tobien, N.; Todenhagen, R.; Truöl, P.; Zálešák, J.; Tsipolitis, G.; Turnau, J.; Tzamariudaki, E.; Uelkes, P.; Usik, A.; Valkár, S.; Valkárová, A.; Vallée, C.; van Esch, P.; van Mechelen, P.; Vandenplas, D.; Vazdik, Y.; Verrecchia, P.; Villet, G.; Wacker, K.; Wagener, A.; Wagener, M.; Wallny, R.; Walter, T.; Waugh, B.; Weber, G.; Weber, M.; Wegener, D.; Wegner, A.; Wengler, T.; Werner, M.; West, L. R.; Wiesand, S.; Wilksen, T.; Willard, S.; Winde, M.; Winter, G.-G.; Wittek, C.; Wobisch, M.; Wollatz, H.; Wünsch, E.; Žáček, J.; Zarbock, D.; Zhang, Z.; Zhokin, A.; Zini, P.; Zomer, F.; Zsembery, J.; Zurnedden, M.

1997-12-01

The transition between photoproduction and deep-inelastic scattering is investigated in jet production at the HERA ep collider, using data collected by the H1 experiment. Measurements of the differential inclusive jet cross-sections dσep/dEt* and dσep/dη*, where Et* and η* are the transverse energy and the pseudorapidity of the jets in the virtual photon-proton centre of mass frame, are presented for 0

Putting 3D modelling and 3D printing into practice: virtual surgery and preoperative planning to reconstruct complex post-traumatic skeletal deformities and defects

PubMed Central

Tetsworth, Kevin; Block, Steve; Glatt, Vaida

2017-01-01

3D printing technology has revolutionized and gradually transformed manufacturing across a broad spectrum of industries, including healthcare. Nowhere is this more apparent than in orthopaedics with many surgeons already incorporating aspects of 3D modelling and virtual procedures into their routine clinical practice. As a more extreme application, patient-specific 3D printed titanium truss cages represent a novel approach for managing the challenge of segmental bone defects. This review illustrates the potential indications of this innovative technique using 3D printed titanium truss cages in conjunction with the Masquelet technique. These implants are custom designed during a virtual surgical planning session with the combined input of an orthopaedic surgeon, an orthopaedic engineering professional and a biomedical design engineer. The ability to 3D model an identical replica of the original intact bone in a virtual procedure is of vital importance when attempting to precisely reconstruct normal anatomy during the actual procedure. Additionally, other important factors must be considered during the planning procedure, such as the three-dimensional configuration of the implant. Meticulous design is necessary to allow for successful implantation through the planned surgical exposure, while being aware of the constraints imposed by local anatomy and prior implants. This review will attempt to synthesize the current state of the art as well as discuss our personal experience using this promising technique. It will address implant design considerations including the mechanical, anatomical and functional aspects unique to each case. PMID:28220752

Putting 3D modelling and 3D printing into practice: virtual surgery and preoperative planning to reconstruct complex post-traumatic skeletal deformities and defects.

PubMed

Tetsworth, Kevin; Block, Steve; Glatt, Vaida

2017-01-01

3D printing technology has revolutionized and gradually transformed manufacturing across a broad spectrum of industries, including healthcare. Nowhere is this more apparent than in orthopaedics with many surgeons already incorporating aspects of 3D modelling and virtual procedures into their routine clinical practice. As a more extreme application, patient-specific 3D printed titanium truss cages represent a novel approach for managing the challenge of segmental bone defects. This review illustrates the potential indications of this innovative technique using 3D printed titanium truss cages in conjunction with the Masquelet technique. These implants are custom designed during a virtual surgical planning session with the combined input of an orthopaedic surgeon, an orthopaedic engineering professional and a biomedical design engineer. The ability to 3D model an identical replica of the original intact bone in a virtual procedure is of vital importance when attempting to precisely reconstruct normal anatomy during the actual procedure. Additionally, other important factors must be considered during the planning procedure, such as the three-dimensional configuration of the implant. Meticulous design is necessary to allow for successful implantation through the planned surgical exposure, while being aware of the constraints imposed by local anatomy and prior implants. This review will attempt to synthesize the current state of the art as well as discuss our personal experience using this promising technique. It will address implant design considerations including the mechanical, anatomical and functional aspects unique to each case. © The Authors, published by EDP Sciences, 2017.

Computer Vision Assisted Virtual Reality Calibration

NASA Technical Reports Server (NTRS)

Kim, W.

1999-01-01

A computer vision assisted semi-automatic virtual reality (VR) calibration technology has been developed that can accurately match a virtual environment of graphically simulated three-dimensional (3-D) models to the video images of the real task environment.

Coming down to Earth: Helping Teachers Use 3D Virtual Worlds in Across-Spaces Learning Situations

ERIC Educational Resources Information Center

Muñoz-Cristóbal, Juan A.; Prieto, Luis P.; Asensio-Pérez, Juan I.; Martínez-Monés, Alejandra; Jorrín-Abellán, Iván M.; Dimitriadis, Yannis

2015-01-01

Different approaches have explored how to provide seamless learning across multiple ICT-enabled physical and virtual spaces, including three-dimensional virtual worlds (3DVW). However, these approaches present limitations that may reduce their acceptance in authentic educational practice: The difficulties of authoring and sharing teacher-created…

Generation IV Nuclear Energy Systems Construction Cost Reductions through the Use of Virtual Environments - Task 4 Report: Virtual Mockup Maintenance Task Evaluation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Timothy Shaw; Anthony Baratta; Vaughn Whisker

2005-02-28

Task 4 report of 3 year DOE NERI-sponsored effort evaluating immersive virtual reality (CAVE) technology for design review, construction planning, and maintenance planning and training for next generation nuclear power plants. Program covers development of full-scale virtual mockups generated from 3D CAD data presented in a CAVE visualization facility. This report focuses on using Full-scale virtual mockups for nuclear power plant training applications.

Rapid prototyping 3D virtual world interfaces within a virtual factory environment

NASA Technical Reports Server (NTRS)

Kosta, Charles Paul; Krolak, Patrick D.

1993-01-01

On-going work into user requirements analysis using CLIPS (NASA/JSC) expert systems as an intelligent event simulator has led to research into three-dimensional (3D) interfaces. Previous work involved CLIPS and two-dimensional (2D) models. Integral to this work was the development of the University of Massachusetts Lowell parallel version of CLIPS, called PCLIPS. This allowed us to create both a Software Bus and a group problem-solving environment for expert systems development. By shifting the PCLIPS paradigm to use the VEOS messaging protocol we have merged VEOS (HlTL/Seattle) and CLIPS into a distributed virtual worlds prototyping environment (VCLIPS). VCLIPS uses the VEOS protocol layer to allow multiple experts to cooperate on a single problem. We have begun to look at the control of a virtual factory. In the virtual factory there are actors and objects as found in our Lincoln Logs Factory of the Future project. In this artificial reality architecture there are three VCLIPS entities in action. One entity is responsible for display and user events in the 3D virtual world. Another is responsible for either simulating the virtual factory or communicating with the real factory. The third is a user interface expert. The interface expert maps user input levels, within the current prototype, to control information for the factory. The interface to the virtual factory is based on a camera paradigm. The graphics subsystem generates camera views of the factory on standard X-Window displays. The camera allows for view control and object control. Control or the factory is accomplished by the user reaching into the camera views to perform object interactions. All communication between the separate CLIPS expert systems is done through VEOS.

Image-based 3D reconstruction and virtual environmental walk-through

NASA Astrophysics Data System (ADS)

Sun, Jifeng; Fang, Lixiong; Luo, Ying

2001-09-01

We present a 3D reconstruction method, which combines geometry-based modeling, image-based modeling and rendering techniques. The first component is an interactive geometry modeling method which recovery of the basic geometry of the photographed scene. The second component is model-based stereo algorithm. We discus the image processing problems and algorithms of walking through in virtual space, then designs and implement a high performance multi-thread wandering algorithm. The applications range from architectural planning and archaeological reconstruction to virtual environments and cinematic special effects.

Microradiography with Semiconductor Pixel Detectors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jakubek, Jan; Cejnarova, Andrea; Dammer, Jiri

High resolution radiography (with X-rays, neutrons, heavy charged particles, ...) often exploited also in tomographic mode to provide 3D images stands as a powerful imaging technique for instant and nondestructive visualization of fine internal structure of objects. Novel types of semiconductor single particle counting pixel detectors offer many advantages for radiation imaging: high detection efficiency, energy discrimination or direct energy measurement, noiseless digital integration (counting), high frame rate and virtually unlimited dynamic range. This article shows the application and potential of pixel detectors (such as Medipix2 or TimePix) in different fields of radiation imaging.

3D-Lab: a collaborative web-based platform for molecular modeling.

PubMed

Grebner, Christoph; Norrby, Magnus; Enström, Jonatan; Nilsson, Ingemar; Hogner, Anders; Henriksson, Jonas; Westin, Johan; Faramarzi, Farzad; Werner, Philip; Boström, Jonas

2016-09-01

The use of 3D information has shown impact in numerous applications in drug design. However, it is often under-utilized and traditionally limited to specialists. We want to change that, and present an approach making 3D information and molecular modeling accessible and easy-to-use 'for the people'. A user-friendly and collaborative web-based platform (3D-Lab) for 3D modeling, including a blazingly fast virtual screening capability, was developed. 3D-Lab provides an interface to automatic molecular modeling, like conformer generation, ligand alignments, molecular dockings and simple quantum chemistry protocols. 3D-Lab is designed to be modular, and to facilitate sharing of 3D-information to promote interactions between drug designers. Recent enhancements to our open-source virtual reality tool Molecular Rift are described. The integrated drug-design platform allows drug designers to instantaneously access 3D information and readily apply advanced and automated 3D molecular modeling tasks, with the aim to improve decision-making in drug design projects.

GPCRs from fusarium graminearum detection, modeling and virtual screening - the search for new routes to control head blight disease.

PubMed

Bresso, Emmanuel; Togawa, Roberto; Hammond-Kosack, Kim; Urban, Martin; Maigret, Bernard; Martins, Natalia Florencio

2016-12-15

Fusarium graminearum (FG) is one of the major cereal infecting pathogens causing high economic losses worldwide and resulting in adverse effects on human and animal health. Therefore, the development of new fungicides against FG is an important issue to reduce cereal infection and economic impact. In the strategy for developing new fungicides, a critical step is the identification of new targets against which innovative chemicals weapons can be designed. As several G-protein coupled receptors (GPCRs) are implicated in signaling pathways critical for the fungi development and survival, such proteins could be valuable efficient targets to reduce Fusarium growth and therefore to prevent food contamination. In this study, GPCRs were predicted in the FG proteome using a manually curated pipeline dedicated to the identification of GPCRs. Based on several successive filters, the most appropriate GPCR candidate target for developing new fungicides was selected. Searching for new compounds blocking this particular target requires the knowledge of its 3D-structure. As no experimental X-Ray structure of the selected protein was available, a 3D model was built by homology modeling. The model quality and stability was checked by 100 ns of molecular dynamics simulations. Two stable conformations representative of the conformational families of the protein were extracted from the 100 ns simulation and were used for an ensemble docking campaign. The model quality and stability was checked by 100 ns of molecular dynamics simulations previously to the virtual screening step. The virtual screening step comprised the exploration of a chemical library with 11,000 compounds that were docked to the GPCR model. Among these compounds, we selected the ten top-ranked nontoxic molecules proposed to be experimentally tested to validate the in silico simulation. This study provides an integrated process merging genomics, structural bioinformatics and drug design for proposing innovative solutions to a world wide threat to grain producers and consumers.

Virtual reality and 3D visualizations in heart surgery education.

PubMed

Friedl, Reinhard; Preisack, Melitta B; Klas, Wolfgang; Rose, Thomas; Stracke, Sylvia; Quast, Klaus J; Hannekum, Andreas; Gödje, Oliver

2002-01-01

Computer assisted teaching plays an increasing role in surgical education. The presented paper describes the development of virtual reality (VR) and 3D visualizations for educational purposes concerning aortocoronary bypass grafting and their prototypical implementation into a database-driven and internet-based educational system in heart surgery. A multimedia storyboard has been written and digital video has been encoded. Understanding of these videos was not always satisfying; therefore, additional 3D and VR visualizations have been modelled as VRML, QuickTime, QuickTime Virtual Reality and MPEG-1 applications. An authoring process in terms of integration and orchestration of different multimedia components to educational units has been started. A virtual model of the heart has been designed. It is highly interactive and the user is able to rotate it, move it, zoom in for details or even fly through. It can be explored during the cardiac cycle and a transparency mode demonstrates coronary arteries, movement of the heart valves, and simultaneous blood-flow. Myocardial ischemia and the effect of an IMA-Graft on myocardial perfusion is simulated. Coronary artery stenoses and bypass-grafts can be interactively added. 3D models of anastomotique techniques and closed thrombendarterectomy have been developed. Different visualizations have been prototypically implemented into a teaching application about operative techniques. Interactive virtual reality and 3D teaching applications can be used and distributed via the World Wide Web and have the power to describe surgical anatomy and principles of surgical techniques, where temporal and spatial events play an important role, in a way superior to traditional teaching methods.

Toward real-time endoscopically-guided robotic navigation based on a 3D virtual surgical field model

NASA Astrophysics Data System (ADS)

Gong, Yuanzheng; Hu, Danying; Hannaford, Blake; Seibel, Eric J.

2015-03-01

The challenge is to accurately guide the surgical tool within the three-dimensional (3D) surgical field for roboticallyassisted operations such as tumor margin removal from a debulked brain tumor cavity. The proposed technique is 3D image-guided surgical navigation based on matching intraoperative video frames to a 3D virtual model of the surgical field. A small laser-scanning endoscopic camera was attached to a mock minimally-invasive surgical tool that was manipulated toward a region of interest (residual tumor) within a phantom of a debulked brain tumor. Video frames from the endoscope provided features that were matched to the 3D virtual model, which were reconstructed earlier by raster scanning over the surgical field. Camera pose (position and orientation) is recovered by implementing a constrained bundle adjustment algorithm. Navigational error during the approach to fluorescence target (residual tumor) is determined by comparing the calculated camera pose to the measured camera pose using a micro-positioning stage. From these preliminary results, computation efficiency of the algorithm in MATLAB code is near real-time (2.5 sec for each estimation of pose), which can be improved by implementation in C++. Error analysis produced 3-mm distance error and 2.5 degree of orientation error on average. The sources of these errors come from 1) inaccuracy of the 3D virtual model, generated on a calibrated RAVEN robotic platform with stereo tracking; 2) inaccuracy of endoscope intrinsic parameters, such as focal length; and 3) any endoscopic image distortion from scanning irregularities. This work demonstrates feasibility of micro-camera 3D guidance of a robotic surgical tool.

Subjective visual vertical assessment with mobile virtual reality system.

PubMed

Ulozienė, Ingrida; Totilienė, Milda; Paulauskas, Andrius; Blažauskas, Tomas; Marozas, Vaidotas; Kaski, Diego; Ulozas, Virgilijus

2017-01-01

The subjective visual vertical (SVV) is a measure of a subject's perceived verticality, and a sensitive test of vestibular dysfunction. Despite this, and consequent upon technical and logistical limitations, SVV has not entered mainstream clinical practice. The aim of the study was to develop a mobile virtual reality based system for SVV test, evaluate the suitability of different controllers and assess the system's usability in practical settings. In this study, we describe a novel virtual reality based system that has been developed to test SVV using integrated software and hardware, and report normative values across healthy population. Participants wore a mobile virtual reality headset in order to observe a 3D stimulus presented across separate conditions - static, dynamic and an immersive real-world ("boat in the sea") SVV tests. The virtual reality environment was controlled by the tester using a Bluetooth connected controllers. Participants controlled the movement of a vertical arrow using either a gesture control armband or a general-purpose gamepad, to indicate perceived verticality. We wanted to compare 2 different methods for object control in the system, determine normal values and compare them with literature data, to evaluate the developed system with the help of the system usability scale questionnaire and evaluate possible virtually induced dizziness with the help of subjective visual analog scale. There were no statistically significant differences in SVV values during static, dynamic and virtual reality stimulus conditions, obtained using the two different controllers and the results are compared to those previously reported in the literature using alternative methodologies. The SUS scores for the system were high, with a median of 82.5 for the Myo controller and of 95.0 for the Gamepad controller, representing a statistically significant difference between the two controllers (P<0.01). The median of virtual reality-induced dizziness for both devices was 0.7. The mobile virtual reality based system for implementation of subjective visual vertical test, is accurate and applicable in the clinical environment. The gamepad-based virtual object control method was preferred by the users. The tests were well tolerated with low dizziness scores in the majority of patients. Copyright © 2018 The Lithuanian University of Health Sciences. Production and hosting by Elsevier Sp. z o.o. All rights reserved.

Web GIS in practice V: 3-D interactive and real-time mapping in Second Life

PubMed Central

Boulos, Maged N Kamel; Burden, David

2007-01-01

This paper describes technologies from Daden Limited for geographically mapping and accessing live news stories/feeds, as well as other real-time, real-world data feeds (e.g., Google Earth KML feeds and GeoRSS feeds) in the 3-D virtual world of Second Life, by plotting and updating the corresponding Earth location points on a globe or some other suitable form (in-world), and further linking those points to relevant information and resources. This approach enables users to visualise, interact with, and even walk or fly through, the plotted data in 3-D. Users can also do the reverse: put pins on a map in the virtual world, and then view the data points on the Web in Google Maps or Google Earth. The technologies presented thus serve as a bridge between mirror worlds like Google Earth and virtual worlds like Second Life. We explore the geo-data display potential of virtual worlds and their likely convergence with mirror worlds in the context of the future 3-D Internet or Metaverse, and reflect on the potential of such technologies and their future possibilities, e.g. their use to develop emergency/public health virtual situation rooms to effectively manage emergencies and disasters in real time. The paper also covers some of the issues associated with these technologies, namely user interface accessibility and individual privacy. PMID:18042275

Accuracy of Three-Dimensional Planning in Surgery-First Orthognathic Surgery: Planning Versus Outcome

PubMed Central

Tran, Ngoc Hieu; Tantidhnazet, Syrina; Raocharernporn, Somchart; Kiattavornchareon, Sirichai; Pairuchvej, Verasak; Wongsirichat, Natthamet

2018-01-01

Background The benefit of computer-assisted planning in orthognathic surgery (OGS) has been extensively documented over the last decade. This study aimed to evaluate the accuracy of three-dimensional (3D) virtual planning in surgery-first OGS. Methods Fifteen patients with skeletal class III malocclusion who underwent bimaxillary OGS with surgery-first approach were included. A composite skull model was reconstructed using data from cone-beam computed tomography and stereolithography from a scanned dental cast. Surgical procedures were simulated using Simplant O&O software, and the virtual plan was transferred to the operation room using 3D-printed splints. Differences of the 3D measurements between the virtual plan and postoperative results were evaluated, and the accuracy was reported using root mean square deviation (RMSD) and the Bland-Altman method. Results The virtual planning was successfully transferred to surgery. The overall mean linear difference was 0.88 mm (0.79 mm for the maxilla and 1 mm for the mandible), and the overall mean angular difference was 1.16°. The RMSD ranged from 0.86 to 1.46 mm and 1.27° to 1.45°, within the acceptable clinical criteria. Conclusion In this study, virtual surgical planning and 3D-printed surgical splints facilitated the diagnosis and treatment planning, and offered an accurate outcome in surgery-first OGS. PMID:29581806

Computer Assisted Virtual Environment - CAVE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Erickson, Phillip; Podgorney, Robert; Weingartner,

Research at the Center for Advanced Energy Studies is taking on another dimension with a 3-D device known as a Computer Assisted Virtual Environment. The CAVE uses projection to display high-end computer graphics on three walls and the floor. By wearing 3-D glasses to create depth perception and holding a wand to move and rotate images, users can delve into data.

The Avenor Virtual Trainer Project--A 3D Interactive Training Module on Energy Control Procedures: Development and First Validation Results.

ERIC Educational Resources Information Center

Giardina, Max

This paper examines the implementation of 3D simulation through the development of the Avenor Virtual Trainer and how situated learning and fidelity of model representation become the basis for more effective Interactive Multimedia Training Situations. The discussion will focus of some principles concerned with situated training, simulation,…

A 3-D Virtual Reality Model of the Sun and the Moon for E-Learning at Elementary Schools

ERIC Educational Resources Information Center

Sun, Koun-Tem; Lin, Ching-Ling; Wang, Sheng-Min

2010-01-01

The relative positions of the sun, moon, and earth, their movements, and their relationships are abstract and difficult to understand astronomical concepts in elementary school science. This study proposes a three-dimensional (3-D) virtual reality (VR) model named the "Sun and Moon System." This e-learning resource was designed by…

Computer Assisted Virtual Environment - CAVE

ScienceCinema

Erickson, Phillip; Podgorney, Robert; Weingartner,

2018-05-30

Research at the Center for Advanced Energy Studies is taking on another dimension with a 3-D device known as a Computer Assisted Virtual Environment. The CAVE uses projection to display high-end computer graphics on three walls and the floor. By wearing 3-D glasses to create depth perception and holding a wand to move and rotate images, users can delve into data.

Communication Modes, Persuasiveness, and Decision-Making Quality: A Comparison of Audio Conferencing, Video Conferencing, and a Virtual Environment

ERIC Educational Resources Information Center

Lockwood, Nicholas S.

2011-01-01

Geographically dispersed teams rely on information and communication technologies (ICTs) to communicate and collaborate. Three ICTs that have received attention are audio conferencing (AC), video conferencing (VC), and, recently, 3D virtual environments (3D VEs). These ICTs offer modes of communication that differ primarily in the number and type…

Virtual Reality and Learning: Where Is the Pedagogy?

ERIC Educational Resources Information Center

Fowler, Chris

2015-01-01

The aim of this paper was to build upon Dalgarno and Lee's model or framework of learning in three-dimensional (3-D) virtual learning environments (VLEs) and to extend their road map for further research in this area. The enhanced model shares the common goal with Dalgarno and Lee of identifying the learning benefits from using 3-D VLEs. The…

Eco-Dialogical Learning and Translanguaging in Open-Ended 3D Virtual Learning Environments: Where Place, Time, and Objects Matter

ERIC Educational Resources Information Center

Zheng, Dongping; Schmidt, Matthew; Hu, Ying; Liu, Min; Hsu, Jesse

2017-01-01

The purpose of this research was to explore the relationships between design, learning, and translanguaging in a 3D collaborative virtual learning environment for adolescent learners of Chinese and English. We designed an open-ended space congruent with ecological and dialogical perspectives on second language acquisition. In such a space,…

Agreement and reliability of pelvic floor measurements during rest and on maximum Valsalva maneuver using three-dimensional translabial ultrasound and virtual reality imaging.

PubMed

Speksnijder, L; Oom, D M J; Koning, A H J; Biesmeijer, C S; Steegers, E A P; Steensma, A B

2016-08-01

Imaging of the levator ani hiatus provides valuable information for the diagnosis and follow-up of patients with pelvic organ prolapse (POP). This study compared measurements of levator ani hiatal volume during rest and on maximum Valsalva, obtained using conventional three-dimensional (3D) translabial ultrasound and virtual reality imaging. Our objectives were to establish their agreement and reliability, and their relationship with prolapse symptoms and POP quantification (POP-Q) stage. One hundred women with an intact levator ani were selected from our tertiary clinic database. Information on clinical symptoms were obtained using standardized questionnaires. Ultrasound datasets were analyzed using a rendered volume with a slice thickness of 1.5 cm, at the level of minimal hiatal dimensions, during rest and on maximum Valsalva. The levator area (in cm(2) ) was measured and multiplied by 1.5 to obtain the levator ani hiatal volume (in cm(3) ) on conventional 3D ultrasound. Levator ani hiatal volume (in cm(3) ) was measured semi-automatically by virtual reality imaging using a segmentation algorithm. Twenty patients were chosen randomly to analyze intra- and interobserver agreement. The mean difference between levator hiatal volume measurements on 3D ultrasound and by virtual reality was 1.52 cm(3) (95% CI, 1.00-2.04 cm(3) ) at rest and 1.16 cm(3) (95% CI, 0.56-1.76 cm(3) ) during maximum Valsalva (P < 0.001). Both intra- and interobserver intraclass correlation coefficients were ≥ 0.96 for conventional 3D ultrasound and > 0.99 for virtual reality. Patients with prolapse symptoms or POP-Q Stage ≥ 2 had significantly larger hiatal measurements than those without symptoms or POP-Q Stage < 2. Levator ani hiatal volume at rest and on maximum Valsalva is significantly smaller when using virtual reality compared with conventional 3D ultrasound; however, this difference does not seem clinically important. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

Impact of 3D virtual planning on reconstruction of mandibular and maxillary surgical defects in head and neck oncology.

PubMed

Witjes, Max J H; Schepers, Rutger H; Kraeima, Joep

2018-04-01

This review describes the advances in 3D virtual planning for mandibular and maxillary reconstruction surgical defects with full prosthetic rehabilitation. The primary purpose is to provide an overview of various techniques that apply 3D technology safely in primary and secondary reconstructive cases of patients suffering from head and neck cancer. Methods have been developed to overcome the problem of control over the margin during surgery while the crucial decision with regard to resection margin and planning of osteotomies were predetermined by virtual planning. The unlimited possibilities of designing patient-specific implants can result in creative uniquely applied solutions for single cases but should be applied wisely with knowledge of biomechanical engineering principles. The high surgical accuracy of an executed 3D virtual plan provides tumor margin control during ablative surgery and the possibility of planned combined use of osseus free flaps and dental implants in the reconstruction in one surgical procedure. A thorough understanding of the effects of radiotherapy on the reconstruction, soft tissue management, and prosthetic rehabilitation is imperative in individual cases when deciding to use dental implants in patients who received radiotherapy.

Advanced 3-dimensional planning in neurosurgery.

PubMed

Ferroli, Paolo; Tringali, Giovanni; Acerbi, Francesco; Schiariti, Marco; Broggi, Morgan; Aquino, Domenico; Broggi, Giovanni

2013-01-01

During the past decades, medical applications of virtual reality technology have been developing rapidly, ranging from a research curiosity to a commercially and clinically important area of medical informatics and technology. With the aid of new technologies, the user is able to process large amounts of data sets to create accurate and almost realistic reconstructions of anatomic structures and related pathologies. As a result, a 3-diensional (3-D) representation is obtained, and surgeons can explore the brain for planning or training. Further improvement such as a feedback system increases the interaction between users and models by creating a virtual environment. Its use for advanced 3-D planning in neurosurgery is described. Different systems of medical image volume rendering have been used and analyzed for advanced 3-D planning: 1 is a commercial "ready-to-go" system (Dextroscope, Bracco, Volume Interaction, Singapore), whereas the others are open-source-based software (3-D Slicer, FSL, and FreesSurfer). Different neurosurgeons at our institution experienced how advanced 3-D planning before surgery allowed them to facilitate and increase their understanding of the complex anatomic and pathological relationships of the lesion. They all agreed that the preoperative experience of virtually planning the approach was helpful during the operative procedure. Virtual reality for advanced 3-D planning in neurosurgery has achieved considerable realism as a result of the available processing power of modern computers. Although it has been found useful to facilitate the understanding of complex anatomic relationships, further effort is needed to increase the quality of the interaction between the user and the model.

Virtual finger boosts three-dimensional imaging and microsurgery as well as terabyte volume image visualization and analysis.

PubMed

Peng, Hanchuan; Tang, Jianyong; Xiao, Hang; Bria, Alessandro; Zhou, Jianlong; Butler, Victoria; Zhou, Zhi; Gonzalez-Bellido, Paloma T; Oh, Seung W; Chen, Jichao; Mitra, Ananya; Tsien, Richard W; Zeng, Hongkui; Ascoli, Giorgio A; Iannello, Giulio; Hawrylycz, Michael; Myers, Eugene; Long, Fuhui

2014-07-11

Three-dimensional (3D) bioimaging, visualization and data analysis are in strong need of powerful 3D exploration techniques. We develop virtual finger (VF) to generate 3D curves, points and regions-of-interest in the 3D space of a volumetric image with a single finger operation, such as a computer mouse stroke, or click or zoom from the 2D-projection plane of an image as visualized with a computer. VF provides efficient methods for acquisition, visualization and analysis of 3D images for roundworm, fruitfly, dragonfly, mouse, rat and human. Specifically, VF enables instant 3D optical zoom-in imaging, 3D free-form optical microsurgery, and 3D visualization and annotation of terabytes of whole-brain image volumes. VF also leads to orders of magnitude better efficiency of automated 3D reconstruction of neurons and similar biostructures over our previous systems. We use VF to generate from images of 1,107 Drosophila GAL4 lines a projectome of a Drosophila brain.

Haptic simulation framework for determining virtual dental occlusion.

PubMed

Wu, Wen; Chen, Hui; Cen, Yuhai; Hong, Yang; Khambay, Balvinder; Heng, Pheng Ann

2017-04-01

The surgical treatment of many dentofacial deformities is often complex due to its three-dimensional nature. To determine the dental occlusion in the most stable position is essential for the success of the treatment. Computer-aided virtual planning on individualized patient-specific 3D model can help formulate the surgical plan and predict the surgical change. However, in current computer-aided planning systems, it is not possible to determine the dental occlusion of the digital models in the intuitive way during virtual surgical planning because of absence of haptic feedback. In this paper, a physically based haptic simulation framework is proposed, which can provide surgeons with the intuitive haptic feedback to determine the dental occlusion of the digital models in their most stable position. To provide the physically realistic force feedback when the dental models contact each other during the searching process, the contact model is proposed to describe the dynamic and collision properties of the dental models during the alignment. The simulated impulse/contact-based forces are integrated into the unified simulation framework. A validation study has been conducted on fifteen sets of virtual dental models chosen at random and covering a wide range of the dental relationships found clinically. The dental occlusions obtained by an expert were employed as a benchmark to compare the virtual occlusion results. The mean translational and angular deviations of the virtual occlusion results from the benchmark were small. The experimental results show the validity of our method. The simulated forces can provide valuable insights to determine the virtual dental occlusion. The findings of this work and the validation of proposed concept lead the way for full virtual surgical planning on patient-specific virtual models allowing fully customized treatment plans for the surgical correction of dentofacial deformities.

Identification of Potent Virtual Leads Specific to S1' Loop of ADAMTS4: Pharmacophore Modeling, 3D-QSAR, Molecular Docking and Dynamic Studies.

PubMed

Suganya, P Rathi; Kalva, Sukesh; Saleena, Lilly M

2016-01-01

ADAMTS4 (Aggrecanase-1) is an important enzyme, which belongs to ADAMTS family. Aggrecanase-1 is involved in aggrecan degradation of articular cartilage in osteoarthritis and rheumatoid arthritis. Overall variability of S1' domain of ADAMTS4 has been the main selectivity determinant to design the unique inhibitors. 34 inhibitors from Binding database and literature were used to develop the pharmacophore model. The five featured pharmacophore model AHHRR had the best survival score of 3.493 and post-hoc score of 2.545, indicating that the model is highly reliable. The 3D-QSAR acquired had excellent r(2) value of 0.99 and GH score of 0.839. The validated pharmacophore model was used for insilico screening of Asinex and ZINC database for finding the potential lead compounds. ZINC00987406 and ASN04459656 which pose high glide score i.e >7 Kcal/mol and H-bond and hydrophobic interactions in the S1'loop residues of ADAMTS4 were subjected to Molecular Dynamics Simulation studies. Molecular dynamic simulation result indicates that the RMSD and RMSF of backbone atoms for the above complexes were within the limit of 2.0 A˚. These compounds can be potential candidates for osteoarthritis by inhibiting ADAMTS4.

Building intuitive 3D interfaces for virtual reality systems

NASA Astrophysics Data System (ADS)

Vaidya, Vivek; Suryanarayanan, Srikanth; Seitel, Mathias; Mullick, Rakesh

2007-03-01

An exploration of techniques for developing intuitive, and efficient user interfaces for virtual reality systems. Work seeks to understand which paradigms from the better-understood world of 2D user interfaces remain viable within 3D environments. In order to establish this a new user interface was created that applied various understood principles of interface design. A user study was then performed where it was compared with an earlier interface for a series of medical visualization tasks.

DE-FG02-04ER25606 Identity Federation and Policy Management Guide: Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Humphrey, Marty, A

The goal of this 3-year project was to facilitate a more productive dynamic matching between resource providers and resource consumers in Grid environments by explicitly specifying policies. There were broadly two problems being addressed by this project. First, there was a lack of an Open Grid Services Architecture (OGSA)-compliant mechanism for expressing, storing and retrieving user policies and Virtual Organization (VO) policies. Second, there was a lack of tools to resolve and enforce policies in the Open Services Grid Architecture. To address these problems, our overall approach in this project was to make all policies explicit (e.g., virtual organization policies,more » resource provider policies, resource consumer policies), thereby facilitating policy matching and policy negotiation. Policies defined on a per-user basis were created, held, and updated in MyPolMan, thereby providing a Grid user to centralize (where appropriate) and manage his/her policies. Organizationally, the corresponding service was VOPolMan, in which the policies of the Virtual Organization are expressed, managed, and dynamically consulted. Overall, we successfully defined, prototyped, and evaluated policy-based resource management and access control for OGSA-based Grids. This DOE project partially supported 17 peer-reviewed publications on a number of different topics: General security for Grids, credential management, Web services/OGSA/OGSI, policy-based grid authorization (for remote execution and for access to information), policy-directed Grid data movement/placement, policies for large-scale virtual organizations, and large-scale policy-aware grid architectures. In addition to supporting the PI, this project partially supported the training of 5 PhD students.« less

The design, production and clinical application of 3D patient-specific implants with drilling guides for acetabular surgery.

PubMed

Merema, B J; Kraeima, J; Ten Duis, K; Wendt, K W; Warta, R; Vos, E; Schepers, R H; Witjes, M J H; IJpma, F F A

2017-11-01

An innovative procedure for the development of 3D patient-specific implants with drilling guides for acetabular fracture surgery is presented. By using CT data and 3D surgical planning software, a virtual model of the fractured pelvis was created. During this process the fracture was virtually reduced. Based on the reduced fracture model, patient-specific titanium plates including polyamide drilling guides were designed, 3D printed and milled for intra-operative use. One of the advantages of this procedure is that the personalised plates could be tailored to both the shape of the pelvis and the type of fracture. The optimal screw directions and sizes were predetermined in the 3D model. The virtual plan was translated towards the surgical procedure by using the surgical guides and patient-specific osteosynthesis. Besides the description of the newly developed multi-disciplinary workflow, a clinical case example is presented to demonstrate that this technique is feasible and promising for the operative treatment of complex acetabular fractures. Copyright © 2017 Elsevier Ltd. All rights reserved.

Elderly Healthcare Monitoring Using an Avatar-Based 3D Virtual Environment

PubMed Central

Pouke, Matti; Häkkilä, Jonna

2013-01-01

Homecare systems for elderly people are becoming increasingly important due to both economic reasons as well as patients’ preferences. Sensor-based surveillance technologies are an expected future trend, but research so far has devoted little attention to the User Interface (UI) design of such systems and the user-centric design approach. In this paper, we explore the possibilities of an avatar-based 3D visualization system, which exploits wearable sensors and human activity simulations. We present a technical prototype and the evaluation of alternative concept designs for UIs based on a 3D virtual world. The evaluation was conducted with homecare providers through focus groups and an online survey. Our results show firstly that systems taking advantage of 3D virtual world visualization techniques have potential especially due to the privacy preserving and simplified information presentation style, and secondly that simple representations and glancability should be emphasized in the design. The identified key use cases highlight that avatar-based 3D presentations can be helpful if they provide an overview as well as details on demand. PMID:24351747

Virtual probing system for medical volume data

NASA Astrophysics Data System (ADS)

Xiao, Yongfei; Fu, Yili; Wang, Shuguo

2007-12-01

Because of the huge computation in 3D medical data visualization, looking into its inner data interactively is always a problem to be resolved. In this paper, we present a novel approach to explore 3D medical dataset in real time by utilizing a 3D widget to manipulate the scanning plane. With the help of the 3D texture property in modern graphics card, a virtual scanning probe is used to explore oblique clipping plane of medical volume data in real time. A 3D model of the medical dataset is also rendered to illustrate the relationship between the scanning-plane image and the other tissues in medical data. It will be a valuable tool in anatomy education and understanding of medical images in the medical research.

Towards Automatic Processing of Virtual City Models for Simulations

NASA Astrophysics Data System (ADS)

Piepereit, R.; Schilling, A.; Alam, N.; Wewetzer, M.; Pries, M.; Coors, V.

2016-10-01

Especially in the field of numerical simulations, such as flow and acoustic simulations, the interest in using virtual 3D models to optimize urban systems is increasing. The few instances in which simulations were already carried out in practice have been associated with an extremely high manual and therefore uneconomical effort for the processing of models. Using different ways of capturing models in Geographic Information System (GIS) and Computer Aided Engineering (CAE), increases the already very high complexity of the processing. To obtain virtual 3D models suitable for simulation, we developed a tool for automatic processing with the goal to establish ties between the world of GIS and CAE. In this paper we introduce a way to use Coons surfaces for the automatic processing of building models in LoD2, and investigate ways to simplify LoD3 models in order to reduce unnecessary information for a numerical simulation.

Value of 3D printing for the comprehension of surgical anatomy.

PubMed

Marconi, Stefania; Pugliese, Luigi; Botti, Marta; Peri, Andrea; Cavazzi, Emma; Latteri, Saverio; Auricchio, Ferdinando; Pietrabissa, Andrea

2017-10-01

In a preliminary experience, we claimed the potential value of 3D printing technology for pre-operative counseling and surgical planning. However, no objective analysis has ever assessed its additional benefit in transferring anatomical information from radiology to final users. We decided to validate the pre-operative use of 3D-printed anatomical models in patients with solid organs' diseases as a new tool to deliver morphological information. Fifteen patients scheduled for laparoscopic splenectomy, nephrectomy, or pancreatectomy were selected and, for each, a full-size 3D virtual anatomical object was reconstructed from a contrast-enhanced MDCT (Multiple Detector Computed Tomography) and then prototyped using a 3D printer. After having carefully evaluated-in a random sequence-conventional contrast MDCT scans, virtual 3D reconstructions on a flat monitor, and 3D-printed models of the same anatomy for each selected case, thirty subjects with different expertise in radiological imaging (10 medical students, 10 surgeons and 10 radiologists) were administered a multiple-item questionnaire. Crucial issues for the anatomical understanding and the pre-operative planning of the scheduled procedure were addressed. The visual and tactile inspection of 3D models allowed the best anatomical understanding, with faster and clearer comprehension of the surgical anatomy. As expected, less experienced medical students perceived the highest benefit (53.9% ± 4.14 of correct answers with 3D-printed models, compared to 53.4 % ± 4.6 with virtual models and 45.5% ± 4.6 with MDCT), followed by surgeons and radiologists. The average time spent by participants in 3D model assessing was shorter (60.67 ± 25.5 s) than the one of the corresponding virtual 3D reconstruction (70.8 ± 28.18 s) or conventional MDCT scan (127.04 ± 35.91 s). 3D-printed models help to transfer complex anatomical information to clinicians, resulting useful in the pre-operative planning, for intra-operative navigation and for surgical training purposes.

D-VASim: an interactive virtual laboratory environment for the simulation and analysis of genetic circuits.

PubMed

Baig, Hasan; Madsen, Jan

2017-01-15

Simulation and behavioral analysis of genetic circuits is a standard approach of functional verification prior to their physical implementation. Many software tools have been developed to perform in silico analysis for this purpose, but none of them allow users to interact with the model during runtime. The runtime interaction gives the user a feeling of being in the lab performing a real world experiment. In this work, we present a user-friendly software tool named D-VASim (Dynamic Virtual Analyzer and Simulator), which provides a virtual laboratory environment to simulate and analyze the behavior of genetic logic circuit models represented in an SBML (Systems Biology Markup Language). Hence, SBML models developed in other software environments can be analyzed and simulated in D-VASim. D-VASim offers deterministic as well as stochastic simulation; and differs from other software tools by being able to extract and validate the Boolean logic from the SBML model. D-VASim is also capable of analyzing the threshold value and propagation delay of a genetic circuit model. D-VASim is available for Windows and Mac OS and can be downloaded from bda.compute.dtu.dk/downloads/. haba@dtu.dk, jama@dtu.dk. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Virtual Worlds? "Outlook Good"

ERIC Educational Resources Information Center

Kelton, AJ

2008-01-01

Many people believed that virtual worlds would end up like the eight-track audiotape: a memory of something no longer used (or useful). Yet today there are hundreds of higher education institutions represented in three-dimensional (3D) virtual worlds such as Active Worlds and Second Life. The movement toward the virtual realm as a viable teaching…

A hybrid 3D spatial access method based on quadtrees and R-trees for globe data

NASA Astrophysics Data System (ADS)

Gong, Jun; Ke, Shengnan; Li, Xiaomin; Qi, Shuhua

2009-10-01

3D spatial access method for globe data is very crucial technique for virtual earth. This paper presents a brand-new maintenance method to index 3d objects distributed on the whole surface of the earth, which integrates the 1:1,000,000- scale topographic map tiles, Quad-tree and R-tree. Furthermore, when traditional methods are extended into 3d space, the performance of spatial index deteriorates badly, for example 3D R-tree. In order to effectively solve this difficult problem, a new algorithm of dynamic R-tree is put forward, which includes two sub-procedures, namely node-choosing and node-split. In the node-choosing algorithm, a new strategy is adopted, not like the traditional mode which is from top to bottom, but firstly from bottom to top then from top to bottom. This strategy can effectively solve the negative influence of node overlap. In the node-split algorithm, 2-to-3 split mode substitutes the traditional 1-to-2 mode, which can better concern the shape and size of nodes. Because of the rational tree shape, this R-tree method can easily integrate the concept of LOD. Therefore, it will be later implemented in commercial DBMS and adopted in time-crucial 3d GIS system.

The Photogrammetric Survey Methodologies Applied to Low Cost 3d Virtual Exploration in Multidisciplinary Field

NASA Astrophysics Data System (ADS)

Palestini, C.; Basso, A.

2017-11-01

In recent years, an increase in international investment in hardware and software technology to support programs that adopt algorithms for photomodeling or data management from laser scanners significantly reduced the costs of operations in support of Augmented Reality and Virtual Reality, designed to generate real-time explorable digital environments integrated to virtual stereoscopic headset. The research analyzes transversal methodologies related to the acquisition of these technologies in order to intervene directly on the phenomenon of acquiring the current VR tools within a specific workflow, in light of any issues related to the intensive use of such devices , outlining a quick overview of the possible "virtual migration" phenomenon, assuming a possible integration with the new internet hyper-speed systems, capable of triggering a massive cyberspace colonization process that paradoxically would also affect the everyday life and more in general, on human space perception. The contribution aims at analyzing the application systems used for low cost 3d photogrammetry by means of a precise pipeline, clarifying how a 3d model is generated, automatically retopologized, textured by color painting or photo-cloning techniques, and optimized for parametric insertion on virtual exploration platforms. Workflow analysis will follow some case studies related to photomodeling, digital retopology and "virtual 3d transfer" of some small archaeological artifacts and an architectural compartment corresponding to the pronaus of Aurum, a building designed in the 1940s by Michelucci. All operations will be conducted on cheap or free licensed software that today offer almost the same performance as their paid counterparts, progressively improving in the data processing speed and management.

Student performance and appreciation using 3D vs. 2D vision in a virtual learning environment.

PubMed

de Boer, I R; Wesselink, P R; Vervoorn, J M

2016-08-01

The aim of this study was to investigate the differences in the performance and appreciation of students working in a virtual learning environment with two (2D)- or three (3D)-dimensional vision. One hundred and twenty-four randomly divided first-year dental students performed a manual dexterity exercise on the Simodont dental trainer with an automatic assessment. Group 1 practised in 2D vision and Group 2 in 3D. All of the students practised five times for 45 min and then took a test using the vision they had practised in. After test 1, all of the students switched the type of vision to control for the learning curve: Group 1 practised in 3D and took a test in 3D, whilst Group 2 practised in 2D and took the test in 2D. To pass, three of five exercises had to be successfully completed within a time limit. The students filled out a questionnaire after completing test 2. The results show that students working with 3D vision achieved significantly better results than students who worked in 2D. Ninety-five per cent of the students filled out the questionnaire, and over 90 per cent preferred 3D vision. The use of 3D vision in a virtual learning environment has a significant positive effect on the performance of the students as well as on their appreciation of the environment. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Customized "In-Office" Three-Dimensional Printing for Virtual Surgical Planning in Craniofacial Surgery.

PubMed

Mendez, Bernardino M; Chiodo, Michael V; Patel, Parit A

2015-07-01

Virtual surgical planning using three-dimensional (3D) printing technology has improved surgical efficiency and precision. A limitation to this technology is that production of 3D surgical models requires a third-party source, leading to increased costs (up to $4000) and prolonged assembly times (averaging 2-3 weeks). The purpose of this study is to evaluate the feasibility, cost, and production time of customized skull models created by an "in-office" 3D printer for craniofacial reconstruction. Two patients underwent craniofacial reconstruction with the assistance of "in-office" 3D printing technology. Three-dimensional skull models were created from a bioplastic filament with a 3D printer using computed tomography (CT) image data. The cost and production time for each model were measured. For both patients, a customized 3D surgical model was used preoperatively to plan split calvarial bone grafting and intraoperatively to more efficiently and precisely perform the craniofacial reconstruction. The average cost for surgical model production with the "in-office" 3D printer was $25 (cost of bioplastic materials used to create surgical model) and the average production time was 14  hours. Virtual surgical planning using "in office" 3D printing is feasible and allows for a more cost-effective and less time consuming method for creating surgical models and guides. By bringing 3D printing to the office setting, we hope to improve intraoperative efficiency, surgical precision, and overall cost for various types of craniofacial and reconstructive surgery.

JAMSTEC E-library of Deep-sea Images (J-EDI) Realizes a Virtual Journey to the Earth's Unexplored Deep Ocean

NASA Astrophysics Data System (ADS)

Sasaki, T.; Azuma, S.; Matsuda, S.; Nagayama, A.; Ogido, M.; Saito, H.; Hanafusa, Y.

2016-12-01

The Japan Agency for Marine-Earth Science and Technology (JAMSTEC) archives a large amount of deep-sea research videos and photos obtained by JAMSTEC's research submersibles and vehicles with cameras. The web site "JAMSTEC E-library of Deep-sea Images : J-EDI" (http://www.godac.jamstec.go.jp/jedi/e/) has made videos and photos available to the public via the Internet since 2011. Users can search for target videos and photos by keywords, easy-to-understand icons, and dive information at J-EDI because operating staffs classify videos and photos as to contents, e.g. living organism and geological environment, and add comments to them.Dive survey data including videos and photos are not only valiant academically but also helpful for education and outreach activities. With the aim of the improvement of visibility for broader communities, we added new functions of 3-dimensional display synchronized various dive survey data with videos in this year.New Functions Users can search for dive survey data by 3D maps with plotted dive points using the WebGL virtual map engine "Cesium". By selecting a dive point, users can watch deep-sea videos and photos and associated environmental data, e.g. water temperature, salinity, rock and biological sample photos, obtained by the dive survey. Users can browse a dive track visualized in 3D virtual spaces using the WebGL JavaScript library. By synchronizing this virtual dive track with videos, users can watch deep-sea videos recorded at a point on a dive track. Users can play an animation which a submersible-shaped polygon automatically traces a 3D virtual dive track and displays of dive survey data are synchronized with tracing a dive track. Users can directly refer to additional information of other JAMSTEC data sites such as marine biodiversity database, marine biological sample database, rock sample database, and cruise and dive information database, on each page which a 3D virtual dive track is displayed. A 3D visualization of a dive track makes users experience a virtual dive survey. In addition, by synchronizing a virtual dive track with videos, it is easy to understand living organisms and geological environments of a dive point. Therefore, these functions will visually support understanding of deep-sea environments in lectures and educational activities.

Scalable Multi-Platform Distribution of Spatial 3d Contents

NASA Astrophysics Data System (ADS)

Klimke, J.; Hagedorn, B.; Döllner, J.

2013-09-01

Virtual 3D city models provide powerful user interfaces for communication of 2D and 3D geoinformation. Providing high quality visualization of massive 3D geoinformation in a scalable, fast, and cost efficient manner is still a challenging task. Especially for mobile and web-based system environments, software and hardware configurations of target systems differ significantly. This makes it hard to provide fast, visually appealing renderings of 3D data throughout a variety of platforms and devices. Current mobile or web-based solutions for 3D visualization usually require raw 3D scene data such as triangle meshes together with textures delivered from server to client, what makes them strongly limited in terms of size and complexity of the models they can handle. In this paper, we introduce a new approach for provisioning of massive, virtual 3D city models on different platforms namely web browsers, smartphones or tablets, by means of an interactive map assembled from artificial oblique image tiles. The key concept is to synthesize such images of a virtual 3D city model by a 3D rendering service in a preprocessing step. This service encapsulates model handling and 3D rendering techniques for high quality visualization of massive 3D models. By generating image tiles using this service, the 3D rendering process is shifted from the client side, which provides major advantages: (a) The complexity of the 3D city model data is decoupled from data transfer complexity (b) the implementation of client applications is simplified significantly as 3D rendering is encapsulated on server side (c) 3D city models can be easily deployed for and used by a large number of concurrent users, leading to a high degree of scalability of the overall approach. All core 3D rendering techniques are performed on a dedicated 3D rendering server, and thin-client applications can be compactly implemented for various devices and platforms.

Application of a distributed network in computational fluid dynamic simulations

NASA Technical Reports Server (NTRS)

Deshpande, Manish; Feng, Jinzhang; Merkle, Charles L.; Deshpande, Ashish

1994-01-01

A general-purpose 3-D, incompressible Navier-Stokes algorithm is implemented on a network of concurrently operating workstations using parallel virtual machine (PVM) and compared with its performance on a CRAY Y-MP and on an Intel iPSC/860. The problem is relatively computationally intensive, and has a communication structure based primarily on nearest-neighbor communication, making it ideally suited to message passing. Such problems are frequently encountered in computational fluid dynamics (CDF), and their solution is increasingly in demand. The communication structure is explicitly coded in the implementation to fully exploit the regularity in message passing in order to produce a near-optimal solution. Results are presented for various grid sizes using up to eight processors.

Journey to the centre of the cell: Virtual reality immersion into scientific data.

PubMed

Johnston, Angus P R; Rae, James; Ariotti, Nicholas; Bailey, Benjamin; Lilja, Andrew; Webb, Robyn; Ferguson, Charles; Maher, Sheryl; Davis, Thomas P; Webb, Richard I; McGhee, John; Parton, Robert G

2018-02-01

Visualization of scientific data is crucial not only for scientific discovery but also to communicate science and medicine to both experts and a general audience. Until recently, we have been limited to visualizing the three-dimensional (3D) world of biology in 2 dimensions. Renderings of 3D cells are still traditionally displayed using two-dimensional (2D) media, such as on a computer screen or paper. However, the advent of consumer grade virtual reality (VR) headsets such as Oculus Rift and HTC Vive means it is now possible to visualize and interact with scientific data in a 3D virtual world. In addition, new microscopic methods provide an unprecedented opportunity to obtain new 3D data sets. In this perspective article, we highlight how we have used cutting edge imaging techniques to build a 3D virtual model of a cell from serial block-face scanning electron microscope (SBEM) imaging data. This model allows scientists, students and members of the public to explore and interact with a "real" cell. Early testing of this immersive environment indicates a significant improvement in students' understanding of cellular processes and points to a new future of learning and public engagement. In addition, we speculate that VR can become a new tool for researchers studying cellular architecture and processes by populating VR models with molecular data. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Performance analysis and evaluation of direct phase measuring deflectometry

NASA Astrophysics Data System (ADS)

Zhao, Ping; Gao, Nan; Zhang, Zonghua; Gao, Feng; Jiang, Xiangqian

2018-04-01

Three-dimensional (3D) shape measurement of specular objects plays an important role in intelligent manufacturing applications. Phase measuring deflectometry (PMD)-based methods are widely used to obtain the 3D shapes of specular surfaces because they offer the advantages of a large dynamic range, high measurement accuracy, full-field and noncontact operation, and automatic data processing. To enable measurement of specular objects with discontinuous and/or isolated surfaces, a direct PMD (DPMD) method has been developed to build a direct relationship between phase and depth. In this paper, a new virtual measurement system is presented and is used to optimize the system parameters and evaluate the system's performance in DPMD applications. Four system parameters are analyzed to obtain accurate measurement results. Experiments are performed using simulated and actual data and the results confirm the effects of these four parameters on the measurement results. Researchers can therefore select suitable system parameters for actual DPMD (including PMD) measurement systems to obtain the 3D shapes of specular objects with high accuracy.

True 3D digital holographic tomography for virtual reality applications

NASA Astrophysics Data System (ADS)

Downham, A.; Abeywickrema, U.; Banerjee, P. P.

2017-09-01

Previously, a single CCD camera has been used to record holograms of an object while the object is rotated about a single axis to reconstruct a pseudo-3D image, which does not show detailed depth information from all perspectives. To generate a true 3D image, the object has to be rotated through multiple angles and along multiple axes. In this work, to reconstruct a true 3D image including depth information, a die is rotated along two orthogonal axes, and holograms are recorded using a Mach-Zehnder setup, which are subsequently numerically reconstructed. This allows for the generation of multiple images containing phase (i.e., depth) information. These images, when combined, create a true 3D image with depth information which can be exported to a Microsoft® HoloLens for true 3D virtual reality.

Monocular display unit for 3D display with correct depth perception

NASA Astrophysics Data System (ADS)

Sakamoto, Kunio; Hosomi, Takashi

2009-11-01

A study of virtual-reality system has been popular and its technology has been applied to medical engineering, educational engineering, a CAD/CAM system and so on. The 3D imaging display system has two types in the presentation method; one is a 3-D display system using a special glasses and the other is the monitor system requiring no special glasses. A liquid crystal display (LCD) recently comes into common use. It is possible for this display unit to provide the same size of displaying area as the image screen on the panel. A display system requiring no special glasses is useful for a 3D TV monitor, but this system has demerit such that the size of a monitor restricts the visual field for displaying images. Thus the conventional display can show only one screen, but it is impossible to enlarge the size of a screen, for example twice. To enlarge the display area, the authors have developed an enlarging method of display area using a mirror. Our extension method enables the observers to show the virtual image plane and to enlarge a screen area twice. In the developed display unit, we made use of an image separating technique using polarized glasses, a parallax barrier or a lenticular lens screen for 3D imaging. The mirror can generate the virtual image plane and it enlarges a screen area twice. Meanwhile the 3D display system using special glasses can also display virtual images over a wide area. In this paper, we present a monocular 3D vision system with accommodation mechanism, which is useful function for perceiving depth.

Application of an innovative computerized virtual planning system in acetabular fracture surgery: A feasibility study.

PubMed

Wang, Huixiang; Wang, Fang; Newman, Simon; Lin, Yanping; Chen, Xiaojun; Xu, Lu; Wang, Qiugen

2016-08-01

Acetabular fracture surgery is amongst the most challenging tasks in the field of trauma surgery and careful preoperative planning is crucial for success. The aim of this paper is to describe the preliminary outcome of the utilization of an innovative computerized virtual planning system for acetabular fractures. 3D models of acetabular fractures and surrounding soft tissues from six patients were constructed from preoperative CT scans. A novel highly-automatic segmentation technique was performed on the 3D model to separate each fracture fragment, then 3D virtual reduction was performed. Additionally, the models were used to assess potential surgical approaches with reference to both the fracture and the surrounding soft tissues. The time required for virtual planning was recorded. After surgery, the virtual plan was compared to the real surgery with respect to surgical approach and reduction sequence. A Likert scale questionnaire was completed by the surgeons to evaluate their satisfaction with the system. Virtual planning was successfully completed in all cases. The planned surgical approach was followed in all cases with the planned reduction sequence followed completely in five cases and partially in one. The mean time required for virtual planning was 38.7min (range 21-57, SD=15.5). The mean time required for planning of B-type fractures was 25.0min (range 21-30, SD=4.6), of C-type fracture 52.3min (range 49-57, SD=4.2). The results of the questionnaire demonstrated a high level of satisfaction with the planning system. This study demonstrates that the virtual planning system is feasible in clinical settings with high satisfaction and acceptability from the surgeons. It provides a viable option for the planning of acetabular fracture surgery. Copyright © 2016 Elsevier Ltd. All rights reserved.

A glimpse of gluons through deeply virtual compton scattering on the proton

DOE Office of Scientific and Technical Information (OSTI.GOV)

Defurne, Maxime; Jimenez-Arguello, A. Marti; Ahmed, Z.

The proton is composed of quarks and gluons, bound by the most elusive mechanism of strong interaction called confinement. In this work, the dynamics of quarks and gluons are investigated using deeply virtual Compton scattering (DVCS): produced by a multi-GeV electron, a highly virtual photon scatters off the proton which subsequently radiates a high energy photon. Similarly to holography, measuring not only the magnitude but also the phase of the DVCS amplitude allows to perform 3D images of the internal structure of the proton. The phase is made accessible through the quantum-mechanical interference of DVCS with the Bethe-Heitler (BH) process,more » in which the final photon is emitted by the electron rather than the proton. Here, we report herein the first full determination of the BH-DVCS interference by exploiting the distinct energy dependences of the DVCS and BH amplitudes. In the high energy regime where the scattering process is expected to occur off a single quark in the proton, these accurate measurements show an intriguing sensitivity to gluons, the carriers of the strong interaction.« less

A glimpse of gluons through deeply virtual compton scattering on the proton

DOE PAGES

Defurne, Maxime; Jimenez-Arguello, A. Marti; Ahmed, Z.; ...

2017-11-10

The proton is composed of quarks and gluons, bound by the most elusive mechanism of strong interaction called confinement. In this work, the dynamics of quarks and gluons are investigated using deeply virtual Compton scattering (DVCS): produced by a multi-GeV electron, a highly virtual photon scatters off the proton which subsequently radiates a high energy photon. Similarly to holography, measuring not only the magnitude but also the phase of the DVCS amplitude allows to perform 3D images of the internal structure of the proton. The phase is made accessible through the quantum-mechanical interference of DVCS with the Bethe-Heitler (BH) process,more » in which the final photon is emitted by the electron rather than the proton. Here, we report herein the first full determination of the BH-DVCS interference by exploiting the distinct energy dependences of the DVCS and BH amplitudes. In the high energy regime where the scattering process is expected to occur off a single quark in the proton, these accurate measurements show an intriguing sensitivity to gluons, the carriers of the strong interaction.« less

Minimally invasive superficial temporal artery to middle cerebral artery bypass through a minicraniotomy: benefit of three-dimensional virtual reality planning using magnetic resonance angiography.

PubMed

Fischer, Gerrit; Stadie, Axel; Schwandt, Eike; Gawehn, Joachim; Boor, Stephan; Marx, Juergen; Oertel, Joachim

2009-05-01

The aim of the authors in this study was to introduce a minimally invasive superficial temporal artery to middle cerebral artery (STA-MCA) bypass surgery by the preselection of appropriate donor and recipient branches in a 3D virtual reality setting based on 3-T MR angiography data. An STA-MCA anastomosis was performed in each of 5 patients. Before surgery, 3-T MR imaging was performed with 3D magnetization-prepared rapid acquisition gradient echo sequences, and a high-resolution CT 3D dataset was obtained. Image fusion and the construction of a 3D virtual reality model of each patient were completed. In the 3D virtual reality setting, the skin surface, skull surface, and extra- and intracranial arteries as well as the cortical brain surface could be displayed in detail. The surgical approach was successfully visualized in virtual reality. The anatomical relationship of structures of interest could be evaluated based on different values of translucency in all cases. The closest point of the appropriate donor branch of the STA and the most suitable recipient M(3) or M(4) segment could be calculated with high accuracy preoperatively and determined as the center point of the following minicraniotomy. Localization of the craniotomy and the skin incision on top of the STA branch was calculated with the system, and these data were transferred onto the patient's skin before surgery. In all cases the preselected arteries could be found intraoperatively in exact agreement with the preoperative planning data. Successful extracranial-intracranial bypass surgery was achieved without stereotactic neuronavigation via a preselected minimally invasive approach in all cases. Subsequent enlargement of the craniotomy was not necessary. Perioperative complications were not observed. All bypasses remained patent on follow-up. With the application of a 3D virtual reality planning system, the extent of skin incision and tissue trauma as well as the size of the bone flap was minimal. The closest point of the appropriate donor branch of the STA and the most suitable recipient M(3) or M(4) segment could be preoperatively determined with high accuracy so that the STA-MCA bypass could be safely and effectively performed through an optimally located minicraniotomy with a mean diameter of 22 mm without the need for stereotactic guidance.

Supporting Distributed Team Working in 3D Virtual Worlds: A Case Study in Second Life

ERIC Educational Resources Information Center

Minocha, Shailey; Morse, David R.

2010-01-01

Purpose: The purpose of this paper is to report on a study into how a three-dimensional (3D) virtual world (Second Life) can facilitate socialisation and team working among students working on a team project at a distance. This models the situation in many commercial sectors where work is increasingly being conducted across time zones and between…

An Australian and New Zealand Scoping Study on the Use of 3D Immersive Virtual Worlds in Higher Education

ERIC Educational Resources Information Center

Dalgarno, Barney; Lee, Mark J. W.; Carlson, Lauren; Gregory, Sue; Tynan, Belinda

2011-01-01

This article describes the research design of, and reports selected findings from, a scoping study aimed at examining current and planned applications of 3D immersive virtual worlds at higher education institutions across Australia and New Zealand. The scoping study is the first of its kind in the region, intended to parallel and complement a…

Three Primary School Students' Cognition about 3D Rotation in a Virtual Reality Learning Environment

ERIC Educational Resources Information Center

Yeh, Andy

2010-01-01

This paper reports on three primary school students' explorations of 3D rotation in a virtual reality learning environment (VRLE) named VRMath. When asked to investigate if you would face the same direction when you turn right 45 degrees first then roll up 45 degrees, or when you roll up 45 degrees first then turn right 45 degrees, the students…

The Effect of 3D Virtual Learning Environment on Secondary School Third Grade Students' Attitudes toward Mathematics

ERIC Educational Resources Information Center

Simsek, Irfan

2016-01-01

With this research, in Second Life environment which is a three dimensional online virtual world, it is aimed to reveal the effects of student attitudes toward mathematics courses and design activities which will enable the third grade students of secondary school (primary education seventh grade) to see the 3D objects in mathematics courses in a…

A 3D virtual reality simulator for training of minimally invasive surgery.

PubMed

Mi, Shao-Hua; Hou, Zeng-Gunag; Yang, Fan; Xie, Xiao-Liang; Bian, Gui-Bin

2014-01-01

For the last decade, remarkable progress has been made in the field of cardiovascular disease treatment. However, these complex medical procedures require a combination of rich experience and technical skills. In this paper, a 3D virtual reality simulator for core skills training in minimally invasive surgery is presented. The system can generate realistic 3D vascular models segmented from patient datasets, including a beating heart, and provide a real-time computation of force and force feedback module for surgical simulation. Instruments, such as a catheter or guide wire, are represented by a multi-body mass-spring model. In addition, a realistic user interface with multiple windows and real-time 3D views are developed. Moreover, the simulator is also provided with a human-machine interaction module that gives doctors the sense of touch during the surgery training, enables them to control the motion of a virtual catheter/guide wire inside a complex vascular model. Experimental results show that the simulator is suitable for minimally invasive surgery training.

Blood Pool Segmentation Results in Superior Virtual Cardiac Models than Myocardial Segmentation for 3D Printing.

PubMed

Farooqi, Kanwal M; Lengua, Carlos Gonzalez; Weinberg, Alan D; Nielsen, James C; Sanz, Javier

2016-08-01

The method of cardiac magnetic resonance (CMR) three-dimensional (3D) image acquisition and post-processing which should be used to create optimal virtual models for 3D printing has not been studied systematically. Patients (n = 19) who had undergone CMR including both 3D balanced steady-state free precession (bSSFP) imaging and contrast-enhanced magnetic resonance angiography (MRA) were retrospectively identified. Post-processing for the creation of virtual 3D models involved using both myocardial (MS) and blood pool (BP) segmentation, resulting in four groups: Group 1-bSSFP/MS, Group 2-bSSFP/BP, Group 3-MRA/MS and Group 4-MRA/BP. The models created were assessed by two raters for overall quality (1-poor; 2-good; 3-excellent) and ability to identify predefined vessels (1-5: superior vena cava, inferior vena cava, main pulmonary artery, ascending aorta and at least one pulmonary vein). A total of 76 virtual models were created from 19 patient CMR datasets. The mean overall quality scores for Raters 1/2 were 1.63 ± 0.50/1.26 ± 0.45 for Group 1, 2.12 ± 0.50/2.26 ± 0.73 for Group 2, 1.74 ± 0.56/1.53 ± 0.61 for Group 3 and 2.26 ± 0.65/2.68 ± 0.48 for Group 4. The numbers of identified vessels for Raters 1/2 were 4.11 ± 1.32/4.05 ± 1.31 for Group 1, 4.90 ± 0.46/4.95 ± 0.23 for Group 2, 4.32 ± 1.00/4.47 ± 0.84 for Group 3 and 4.74 ± 0.56/4.63 ± 0.49 for Group 4. Models created using BP segmentation (Groups 2 and 4) received significantly higher ratings than those created using MS for both overall quality and number of vessels visualized (p < 0.05), regardless of the acquisition technique. There were no significant differences between Groups 1 and 3. The ratings for Raters 1 and 2 had good correlation for overall quality (ICC = 0.63) and excellent correlation for the total number of vessels visualized (ICC = 0.77). The intra-rater reliability was good for Rater A (ICC = 0.65). Three models were successfully printed on desktop 3D printers with good quality and accurate representation of the virtual 3D models. We recommend using BP segmentation with either MRA or bSSFP source datasets to create virtual 3D models for 3D printing. Desktop 3D printers can offer good quality printed models with accurate representation of anatomic detail.

ConfocalVR: Immersive Visualization Applied to Confocal Microscopy.

PubMed

Stefani, Caroline; Lacy-Hulbert, Adam; Skillman, Thomas

2018-06-24

ConfocalVR is a virtual reality (VR) application created to improve the ability of researchers to study the complexity of cell architecture. Confocal microscopes take pictures of fluorescently labeled proteins or molecules at different focal planes to create a stack of 2D images throughout the specimen. Current software applications reconstruct the 3D image and render it as a 2D projection onto a computer screen where users need to rotate the image to expose the full 3D structure. This process is mentally taxing, breaks down if you stop the rotation, and does not take advantage of the eye's full field of view. ConfocalVR exploits consumer-grade virtual reality (VR) systems to fully immerse the user in the 3D cellular image. In this virtual environment the user can: 1) adjust image viewing parameters without leaving the virtual space, 2) reach out and grab the image to quickly rotate and scale the image to focus on key features, and 3) interact with other users in a shared virtual space enabling real-time collaborative exploration and discussion. We found that immersive VR technology allows the user to rapidly understand cellular architecture and protein or molecule distribution. We note that it is impossible to understand the value of immersive visualization without experiencing it first hand, so we encourage readers to get access to a VR system, download this software, and evaluate it for yourself. The ConfocalVR software is available for download at http://www.confocalvr.com, and is free for nonprofits. Copyright © 2018. Published by Elsevier Ltd.

The differential algebra based multiple level fast multipole algorithm for 3D space charge field calculation and photoemission simulation

DOE PAGES

None, None

2015-09-28

Coulomb interaction between charged particles inside a bunch is one of the most importance collective effects in beam dynamics, becoming even more significant as the energy of the particle beam is lowered to accommodate analytical and low-Z material imaging purposes such as in the time resolved Ultrafast Electron Microscope (UEM) development currently underway at Michigan State University. In addition, space charge effects are the key limiting factor in the development of ultrafast atomic resolution electron imaging and diffraction technologies and are also correlated with an irreversible growth in rms beam emittance due to fluctuating components of the nonlinear electron dynamics.more » In the short pulse regime used in the UEM, space charge effects also lead to virtual cathode formation in which the negative charge of the electrons emitted at earlier times, combined with the attractive surface field, hinders further emission of particles and causes a degradation of the pulse properties. Space charge and virtual cathode effects and their remediation are core issues for the development of the next generation of high-brightness UEMs. Since the analytical models are only applicable for special cases, numerical simulations, in addition to experiments, are usually necessary to accurately understand the space charge effect. In this paper we will introduce a grid-free differential algebra based multiple level fast multipole algorithm, which calculates the 3D space charge field for n charged particles in arbitrary distribution with an efficiency of O(n), and the implementation of the algorithm to a simulation code for space charge dominated photoemission processes.« less

An optical tracking system for virtual reality

NASA Astrophysics Data System (ADS)

Hrimech, Hamid; Merienne, Frederic

2009-03-01

In this paper we present a low-cost 3D tracking system which we have developed and tested in order to move away from traditional 2D interaction techniques (keyboard and mouse) in an attempt to improve user's experience while using a CVE. Such a tracking system is used to implement 3D interaction techniques that augment user experience, promote user's sense of transportation in the virtual world as well as user's awareness of their partners. The tracking system is a passive optical tracking system using stereoscopy a technique allowing the reconstruction of three-dimensional information from a couple of images. We have currently deployed our 3D tracking system on a collaborative research platform for investigating 3D interaction techniques in CVEs.

Using Digital Earth to create online scientific reality tourist guides to tourist attractions in Taiwan, China

NASA Astrophysics Data System (ADS)

Ding, Yea-Chung

2010-11-01

In recent years national parks worldwide have introduced online virtual tourism, through which potential visitors can search for tourist information. Most virtual tourism websites are a simulation of an existing location, usually composed of panoramic images, a sequence of hyperlinked still or video images, and/or virtual models of the actual location. As opposed to actual tourism, a virtual tour is typically accessed on a personal computer or an interactive kiosk. Using modern Digital Earth techniques such as high resolution satellite images, precise GPS coordinates and powerful 3D WebGIS, however, it's possible to create more realistic scenic models to present natural terrain and man-made constructions in greater detail. This article explains how to create an online scientific reality tourist guide for the Jinguashi Gold Ecological Park at Jinguashi in northern Taiwan, China. This project uses high-resolution Formosat 2 satellite images and digital aerial images in conjunction with DTM to create a highly realistic simulation of terrain, with the addition of 3DMAX to add man-made constructions and vegetation. Using this 3D Geodatabase model in conjunction with INET 3D WebGIS software, we have found Digital Earth concept can greatly improve and expand the presentation of traditional online virtual tours on the websites.

Internet-based distributed collaborative environment for engineering education and design

NASA Astrophysics Data System (ADS)

Sun, Qiuli

2001-07-01

This research investigates the use of the Internet for engineering education, design, and analysis through the presentation of a Virtual City environment. The main focus of this research was to provide an infrastructure for engineering education, test the concept of distributed collaborative design and analysis, develop and implement the Virtual City environment, and assess the environment's effectiveness in the real world. A three-tier architecture was adopted in the development of the prototype, which contains an online database server, a Web server as well as multi-user servers, and client browsers. The environment is composed of five components, a 3D virtual world, multiple Internet-based multimedia modules, an online database, a collaborative geometric modeling module, and a collaborative analysis module. The environment was designed using multiple Intenet-based technologies, such as Shockwave, Java, Java 3D, VRML, Perl, ASP, SQL, and a database. These various technologies together formed the basis of the environment and were programmed to communicate smoothly with each other. Three assessments were conducted over a period of three semesters. The Virtual City is open to the public at www.vcity.ou.edu. The online database was designed to manage the changeable data related to the environment. The virtual world was used to implement 3D visualization and tie the multimedia modules together. Students are allowed to build segments of the 3D virtual world upon completion of appropriate undergraduate courses in civil engineering. The end result is a complete virtual world that contains designs from all of their coursework and is viewable on the Internet. The environment is a content-rich educational system, which can be used to teach multiple engineering topics with the help of 3D visualization, animations, and simulations. The concept of collaborative design and analysis using the Internet was investigated and implemented. Geographically dispersed users can build the same geometric model simultaneously over the Internet and communicate with each other through a chat room. They can also conduct finite element analysis collaboratively on the same object over the Internet. They can mesh the same object, apply and edit the same boundary conditions and forces, obtain the same analysis results, and then discuss the results through the Internet.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gonzalez Anez, Francisco

This paper presents two development projects (STARMATE and VIRMAN) focused on supporting training on maintenance. Both projects aim at specifying, designing, developing, and demonstrating prototypes allowing computer guided maintenance of complex mechanical elements using Augmented and Virtual Reality techniques. VIRMAN is a Spanish development project. The objective is to create a computer tool for maintenance training course elaborations and training delivery based on 3D virtual reality models of complex components. The training delivery includes 3D record displays on maintenance procedures with all complementary information for intervention understanding. Users are requested to perform the maintenance intervention trying to follow up themore » procedure. Users can be evaluated about the level of knowledge achieved. Instructors can check the evaluation records left during the training sessions. VIRMAN is simple software supported by a regular computer and can be used in an Internet framework. STARMATE is a forward step in the area of virtual reality. STARMATE is a European Commission project in the frame of 'Information Societies Technologies'. A consortium of five companies and one research institute shares their expertise in this new technology. STARMATE provides two main functionalities (1) user assistance for achieving assembly/de-assembly and following maintenance procedures, and (2) workforce training. The project relies on Augmented Reality techniques, which is a growing area in Virtual Reality research. The idea of Augmented Reality is to combine a real scene, viewed by the user, with a virtual scene, generated by a computer, augmenting the reality with additional information. The user interface is see-through goggles, headphones, microphone and an optical tracking system. All these devices are integrated in a helmet connected with two regular computers. The user has his hands free for performing the maintenance intervention and he can navigate in the virtual world thanks to a voice recognition system and a virtual pointing device. The maintenance work is guided with audio instructions, 2D and 3D information are directly displayed into the user's goggles: There is a position-tracking system that allows 3D virtual models to be displayed in the real counterpart positions independently of the user allocation. The user can create his own virtual environment, placing the information required wherever he wants. The STARMATE system is applicable to a large variety of real work situations. (author)« less

a Low-Cost and Lightweight 3d Interactive Real Estate-Purposed Indoor Virtual Reality Application

NASA Astrophysics Data System (ADS)

Ozacar, K.; Ortakci, Y.; Kahraman, I.; Durgut, R.; Karas, I. R.

2017-11-01

Interactive 3D architectural indoor design have been more popular after it benefited from Virtual Reality (VR) technologies. VR brings computer-generated 3D content to real life scale and enable users to observe immersive indoor environments so that users can directly modify it. This opportunity enables buyers to purchase a property off-the-plan cheaper through virtual models. Instead of showing property through 2D plan or renders, this visualized interior architecture of an on-sale unbuilt property is demonstrated beforehand so that the investors have an impression as if they were in the physical building. However, current applications either use highly resource consuming software, or are non-interactive, or requires specialist to create such environments. In this study, we have created a real-estate purposed low-cost high quality fully interactive VR application that provides a realistic interior architecture of the property by using free and lightweight software: Sweet Home 3D and Unity. A preliminary study showed that participants generally liked proposed real estate-purposed VR application, and it satisfied the expectation of the property buyers.

Virtual Reality Enhanced Instructional Learning

ERIC Educational Resources Information Center

Nachimuthu, K.; Vijayakumari, G.

2009-01-01

Virtual Reality (VR) is a creation of virtual 3D world in which one can feel and sense the world as if it is real. It is allowing engineers to design machines and Educationists to design AV [audiovisual] equipment in real time but in 3-dimensional hologram as if the actual material is being made and worked upon. VR allows a least-cost (energy…

From stereoscopic recording to virtual reality headsets: Designing a new way to learn surgery.

PubMed

Ros, M; Trives, J-V; Lonjon, N

2017-03-01

To improve surgical practice, there are several different approaches to simulation. Due to wearable technologies, recording 3D movies is now easy. The development of a virtual reality headset allows imagining a different way of watching these videos: using dedicated software to increase interactivity in a 3D immersive experience. The objective was to record 3D movies via a main surgeon's perspective, to watch files using virtual reality headsets and to validate pedagogic interest. Surgical procedures were recorded using a system combining two side-by-side cameras placed on a helmet. We added two LEDs just below the cameras to enhance luminosity. Two files were obtained in mp4 format and edited using dedicated software to create 3D movies. Files obtained were then played using a virtual reality headset. Surgeons who tried the immersive experience completed a questionnaire to evaluate the interest of this procedure for surgical learning. Twenty surgical procedures were recorded. The movies capture a scene which is extended 180° horizontally and 90° vertically. The immersive experience created by the device conveys a genuine feeling of being in the operating room and seeing the procedure first-hand through the eyes of the main surgeon. All surgeons indicated that they believe in pedagogical interest of this method. We succeeded in recording the main surgeon's point of view in 3D and watch it on a virtual reality headset. This new approach enhances the understanding of surgery; most of the surgeons appreciated its pedagogic value. This method could be an effective learning tool in the future. Copyright © 2016. Published by Elsevier Masson SAS.

In silico approaches to identify novel myeloid cell leukemia-1 (Mcl-1) inhibitors for treatment of cancer.

PubMed

Ren, Ji-Xia; Li, Cheng-Ping; Zhou, Xiu-Ling; Cao, Xue-Song; Xie, Yong

2017-08-22

Myeloid cell leukemia-1 (Mcl-1) has been a validated and attractive target for cancer therapy. Over-expression of Mcl-1 in many cancers allows cancer cells to evade apoptosis and contributes to the resistance to current chemotherapeutics. Here, we identified new Mcl-1 inhibitors using a multi-step virtual screening approach. First, based on two different ligand-receptor complexes, 20 pharmacophore models were established by simultaneously using 'Receptor-Ligand Pharmacophore Generation' method and manual build feature method, and then carefully validated by a test database. Then, pharmacophore-based virtual screening (PB-VS) could be performed by using the 20 pharmacophore models. In addition, docking study was used to predict the possible binding poses of compounds, and the docking parameters were optimized before performing docking-based virtual screening (DB-VS). Moreover, a 3D QSAR model was established by applying the 55 aligned Mcl-1 inhibitors. The 55 inhibitors sharing the same scaffold were docked into the Mcl-1 active site before alignment, then the inhibitors with possible binding conformations were aligned. For the training set, the 3D QSAR model gave a correlation coefficient r 2 of 0.996; for the test set, the correlation coefficient r 2 was 0.812. Therefore, the developed 3D QSAR model was a good model, which could be applied for carrying out 3D QSAR-based virtual screening (QSARD-VS). After the above three virtual screening methods orderly filtering, 23 potential inhibitors with novel scaffolds were identified. Furthermore, we have discussed in detail the mapping results of two potent compounds onto pharmacophore models, 3D QSAR model, and the interactions between the compounds and active site residues.

Immersive 3D geovisualisation in higher education

NASA Astrophysics Data System (ADS)

Philips, Andrea; Walz, Ariane; Bergner, Andreas; Graeff, Thomas; Heistermann, Maik; Kienzler, Sarah; Korup, Oliver; Lipp, Torsten; Schwanghart, Wolfgang; Zeilinger, Gerold

2014-05-01

Through geovisualisation we explore spatial data, we analyse it towards a specific questions, we synthesise results, and we present and communicate them to a specific audience (MacEachren & Kraak 1997). After centuries of paper maps, the means to represent and visualise our physical environment and its abstract qualities have changed dramatically since the 1990s - and accordingly the methods how to use geovisualisation in teaching. Whereas some people might still consider the traditional classroom as ideal setting for teaching and learning geographic relationships and its mapping, we used a 3D CAVE (computer-animated virtual environment) as environment for a problem-oriented learning project called "GEOSimulator". Focussing on this project, we empirically investigated, if such a technological advance like the CAVE make 3D visualisation, including 3D geovisualisation, not only an important tool for businesses (Abulrub et al. 2012) and for the public (Wissen et al. 2008), but also for educational purposes, for which it had hardly been used yet. The 3D CAVE is a three-sided visualisation platform, that allows for immersive and stereoscopic visualisation of observed and simulated spatial data. We examined the benefits of immersive 3D visualisation for geographic research and education and synthesized three fundamental technology-based visual aspects: First, the conception and comprehension of space and location does not need to be generated, but is instantaneously and intuitively present through stereoscopy. Second, optical immersion into virtual reality strengthens this spatial perception which is in particular important for complex 3D geometries. And third, a significant benefit is interactivity, which is enhanced through immersion and allows for multi-discursive and dynamic data exploration and knowledge transfer. Based on our problem-oriented learning project, which concentrates on a case study on flood risk management at the Wilde Weisseritz in Germany, a river that significantly contributed to the hundred-year flooding in Dresden in 2002, we empirically evaluated the usefulness of this immersive 3D technology towards learning success. Results show that immersive 3D geovisualisation have educational and content-related advantages compared to 2D geovisualisations through the mentioned benefits. This innovative way of geovisualisation is thus not only entertaining and motivating for students, but can also be constructive for research studies by, for instance, facilitating the study of complex environments or decision-making processes.

Virtual surgical planning and 3D printing in repeat calvarial vault reconstruction for craniosynostosis: technical note.

PubMed

LoPresti, Melissa; Daniels, Bradley; Buchanan, Edward P; Monson, Laura; Lam, Sandi

2017-04-01

Repeat surgery for restenosis after initial nonsyndromic craniosynostosis intervention is sometimes needed. Calvarial vault reconstruction through a healed surgical bed adds a level of intraoperative complexity and may benefit from preoperative and intraoperative definitions of biometric and aesthetic norms. Computer-assisted design and manufacturing using 3D imaging allows the precise formulation of operative plans in anticipation of surgical intervention. 3D printing turns virtual plans into anatomical replicas, templates, or customized implants by using a variety of materials. The authors present a technical note illustrating the use of this technology: a repeat calvarial vault reconstruction that was planned and executed using computer-assisted design and 3D printed intraoperative guides.

Undertaking qualitative health research in social virtual worlds.

PubMed

McElhinney, Evelyn; Cheater, Francine M; Kidd, Lisa

2014-06-01

This paper discusses the methodological challenges of using the 3D social virtual world Second Life for research and offers some solutions on a range of research issues including research ethics committee approval, gaining consent, recruitment of sample, data collection and engagement with 'in - world culture'. The attraction of social virtual worlds to researchers is their ability to mimic the physical world, as they, are seen as 'places' where people have a feeling of presence (being there) and social presence (being there with others) through the use of a 'customisable' avatar (digital self-representation). Emerging research demonstrating the persuasive nature of avatars on health behaviours through virtual worlds, online games and the 3D web has increased the use of and interest in these areas for delivering health information, advice and support. However, conducting research can be challenging in a 3D world where people are represented as anonymous avatars in an environment unlike any other online media. 25 semi-structured interviews were conducted in Second Life from September 2011-June 2012. Nurses wishing to undertake research in social virtual worlds should spend time in-world to acquire technical skills and gain an understanding of the culture of the world. Our experience of an interview-based study in virtual worlds indicates that researchers require several virtual world technical skills to create innovative tools to recruit, gain consent and collect data and an understanding of in-world culture, language and social norms to increase the chances of successful research. © 2013 John Wiley & Sons Ltd.

Identification of novel Trypanosoma cruzi prolyl oligopeptidase inhibitors by structure-based virtual screening

NASA Astrophysics Data System (ADS)

de Almeida, Hugo; Leroux, Vincent; Motta, Flávia Nader; Grellier, Philippe; Maigret, Bernard; Santana, Jaime M.; Bastos, Izabela Marques Dourado

2016-12-01

We have previously demonstrated that the secreted prolyl oligopeptidase of Trypanosoma cruzi (POPTc80) is involved in the infection process by facilitating parasite migration through the extracellular matrix. We have built a 3D structural model where POPTc80 is formed by a catalytic α/β-hydrolase domain and a β-propeller domain, and in which the substrate docks at the inter-domain interface, suggesting a "jaw opening" gating access mechanism. This preliminary model was refined by molecular dynamics simulations and next used for a virtual screening campaign, whose predictions were tested by standard binding assays. This strategy was successful as all 13 tested molecules suggested from the in silico calculations were found out to be active POPTc80 inhibitors in the micromolar range (lowest K i at 667 nM). This work paves the way for future development of innovative drugs against Chagas disease.

Combination of 2D/3D ligand-based similarity search in rapid virtual screening from multimillion compound repositories. Selection and biological evaluation of potential PDE4 and PDE5 inhibitors.

PubMed

Dobi, Krisztina; Hajdú, István; Flachner, Beáta; Fabó, Gabriella; Szaszkó, Mária; Bognár, Melinda; Magyar, Csaba; Simon, István; Szisz, Dániel; Lőrincz, Zsolt; Cseh, Sándor; Dormán, György

2014-05-28

Rapid in silico selection of target focused libraries from commercial repositories is an attractive and cost effective approach. If structures of active compounds are available rapid 2D similarity search can be performed on multimillion compound databases but the generated library requires further focusing by various 2D/3D chemoinformatics tools. We report here a combination of the 2D approach with a ligand-based 3D method (Screen3D) which applies flexible matching to align reference and target compounds in a dynamic manner and thus to assess their structural and conformational similarity. In the first case study we compared the 2D and 3D similarity scores on an existing dataset derived from the biological evaluation of a PDE5 focused library. Based on the obtained similarity metrices a fusion score was proposed. The fusion score was applied to refine the 2D similarity search in a second case study where we aimed at selecting and evaluating a PDE4B focused library. The application of this fused 2D/3D similarity measure led to an increase of the hit rate from 8.5% (1st round, 47% inhibition at 10 µM) to 28.5% (2nd round at 50% inhibition at 10 µM) and the best two hits had 53 nM inhibitory activities.

Exploring the efficacy of replacing linear paper-based patient cases in problem-based learning with dynamic Web-based virtual patients: randomized controlled trial.

PubMed

Poulton, Terry; Ellaway, Rachel H; Round, Jonathan; Jivram, Trupti; Kavia, Sheetal; Hilton, Sean

2014-11-05

Problem-based learning (PBL) is well established in medical education and beyond, and continues to be developed and explored. Challenges include how to connect the somewhat abstract nature of classroom-based PBL with clinical practice and how to maintain learner engagement in the process of PBL over time. A study was conducted to investigate the efficacy of decision-PBL (D-PBL), a variant form of PBL that replaces linear PBL cases with virtual patients. These Web-based interactive cases provided learners with a series of patient management pathways. Learners were encouraged to consider and discuss courses of action, take their chosen management pathway, and experience the consequences of their decisions. A Web-based application was essential to allow scenarios to respond dynamically to learners' decisions, to deliver the scenarios to multiple PBL classrooms in the same timeframe, and to record centrally the paths taken by the PBL groups. A randomized controlled trial in crossover design was run involving all learners (N=81) in the second year of the graduate entry stream for the undergraduate medicine program at St George's University of London. Learners were randomized to study groups; half engaged in a D-PBL activity whereas the other half had a traditional linear PBL activity on the same subject material. Groups alternated D-PBL and linear PBL over the semester. The measure was mean cohort performance on specific face-to-face exam questions at the end of the semester. D-PBL groups performed better than linear PBL groups on questions related to D-PBL with the difference being statistically significant for all questions. Differences between the exam performances of the 2 groups were not statistically significant for the questions not related to D-PBL. The effect sizes for D-PBL-related questions were large and positive (>0.6) except for 1 question that showed a medium positive effect size. The effect sizes for questions not related to D-PBL were all small (≤0.3) with a mix of positive and negative values. The efficacy of D-PBL was indicated by improved exam performance for learners who had D-PBL compared to those who had linear PBL. This suggests that the use of D-PBL leads to better midterm learning outcomes than linear PBL, at least for learners with prior experience with linear PBL. On the basis of tutor and student feedback, St George's University of London and the University of Nicosia, Cyprus have replaced paper PBL cases for midstage undergraduate teaching with D-PBL virtual patients, and 6 more institutions in the ePBLnet partnership will be implementing D-PBL in Autumn 2015.

Virtual Reality Calibration for Telerobotic Servicing

NASA Technical Reports Server (NTRS)

Kim, W.

1994-01-01

A virtual reality calibration technique of matching a virtual environment of simulated graphics models in 3-D geometry and perspective with actual camera views of the remote site task environment has been developed to enable high-fidelity preview/predictive displays with calibrated graphics overlay on live video.

A 3D character animation engine for multimodal interaction on mobile devices

NASA Astrophysics Data System (ADS)

Sandali, Enrico; Lavagetto, Fabio; Pisano, Paolo

2005-03-01

Talking virtual characters are graphical simulations of real or imaginary persons that enable natural and pleasant multimodal interaction with the user, by means of voice, eye gaze, facial expression and gestures. This paper presents an implementation of a 3D virtual character animation and rendering engine, compliant with the MPEG-4 standard, running on Symbian-based SmartPhones. Real-time animation of virtual characters on mobile devices represents a challenging task, since many limitations must be taken into account with respect to processing power, graphics capabilities, disk space and execution memory size. The proposed optimization techniques allow to overcome these issues, guaranteeing a smooth and synchronous animation of facial expressions and lip movements on mobile phones such as Sony-Ericsson's P800 and Nokia's 6600. The animation engine is specifically targeted to the development of new "Over The Air" services, based on embodied conversational agents, with applications in entertainment (interactive story tellers), navigation aid (virtual guides to web sites and mobile services), news casting (virtual newscasters) and education (interactive virtual teachers).

Cortical Spiking Network Interfaced with Virtual Musculoskeletal Arm and Robotic Arm.

PubMed

Dura-Bernal, Salvador; Zhou, Xianlian; Neymotin, Samuel A; Przekwas, Andrzej; Francis, Joseph T; Lytton, William W

2015-01-01

Embedding computational models in the physical world is a critical step towards constraining their behavior and building practical applications. Here we aim to drive a realistic musculoskeletal arm model using a biomimetic cortical spiking model, and make a robot arm reproduce the same trajectories in real time. Our cortical model consisted of a 3-layered cortex, composed of several hundred spiking model-neurons, which display physiologically realistic dynamics. We interconnected the cortical model to a two-joint musculoskeletal model of a human arm, with realistic anatomical and biomechanical properties. The virtual arm received muscle excitations from the neuronal model, and fed back proprioceptive information, forming a closed-loop system. The cortical model was trained using spike timing-dependent reinforcement learning to drive the virtual arm in a 2D reaching task. Limb position was used to simultaneously control a robot arm using an improved network interface. Virtual arm muscle activations responded to motoneuron firing rates, with virtual arm muscles lengths encoded via population coding in the proprioceptive population. After training, the virtual arm performed reaching movements which were smoother and more realistic than those obtained using a simplistic arm model. This system provided access to both spiking network properties and to arm biophysical properties, including muscle forces. The use of a musculoskeletal virtual arm and the improved control system allowed the robot arm to perform movements which were smoother than those reported in our previous paper using a simplistic arm. This work provides a novel approach consisting of bidirectionally connecting a cortical model to a realistic virtual arm, and using the system output to drive a robotic arm in real time. Our techniques are applicable to the future development of brain neuroprosthetic control systems, and may enable enhanced brain-machine interfaces with the possibility for finer control of limb prosthetics.

Stereo 3D vision adapter using commercial DIY goods

NASA Astrophysics Data System (ADS)

Sakamoto, Kunio; Ohara, Takashi

2009-10-01

The conventional display can show only one screen, but it is impossible to enlarge the size of a screen, for example twice. Meanwhile the mirror supplies us with the same image but this mirror image is usually upside down. Assume that the images on an original screen and a virtual screen in the mirror are completely different and both images can be displayed independently. It would be possible to enlarge a screen area twice. This extension method enables the observers to show the virtual image plane and to enlarge a screen area twice. Although the displaying region is doubled, this virtual display could not produce 3D images. In this paper, we present an extension method using a unidirectional diffusing image screen and an improvement for displaying a 3D image using orthogonal polarized image projection.

Virtual Reconstruction of Lost Architectures: from the Tls Survey to AR Visualization

NASA Astrophysics Data System (ADS)

Quattrini, R.; Pierdicca, R.; Frontoni, E.; Barcaglioni, R.

2016-06-01

The exploitation of high quality 3D models for dissemination of archaeological heritage is currently an investigated topic, although Mobile Augmented Reality platforms for historical architecture are not available, allowing to develop low-cost pipelines for effective contents. The paper presents a virtual anastylosis, starting from historical sources and from 3D model based on TLS survey. Several efforts and outputs in augmented or immersive environments, exploiting this reconstruction, are discussed. The work demonstrates the feasibility of a 3D reconstruction approach for complex architectural shapes starting from point clouds and its AR/VR exploitation, allowing the superimposition with archaeological evidences. Major contributions consist in the presentation and the discussion of a pipeline starting from the virtual model, to its simplification showing several outcomes, comparing also the supported data qualities and advantages/disadvantages due to MAR and VR limitations.

A strategic map for high-impact virtual experience design

NASA Astrophysics Data System (ADS)

Faste, Haakon; Bergamasco, Massimo

2009-02-01

We have employed methodologies of human centered design to inspire and guide the engineering of a definitive low-cost aesthetic multimodal experience intended to stimulate cultural growth. Using a combination of design research, trend analysis and the programming of immersive virtual 3D worlds, over 250 innovative concepts have been brainstormed, prototyped, evaluated and refined. These concepts have been used to create a strategic map for the development of highimpact virtual art experiences, the most promising of which have been incorporated into a multimodal environment programmed in the online interactive 3D platform XVR. A group of test users have evaluated the experience as it has evolved, using a multimodal interface with stereo vision, 3D audio and haptic feedback. This paper discusses the process, content, results, and impact on our engineering laboratory that this research has produced.

3-D Sound for Virtual Reality and Multimedia

NASA Technical Reports Server (NTRS)

Begault, Durand R.; Trejo, Leonard J. (Technical Monitor)

2000-01-01

Technology and applications for the rendering of virtual acoustic spaces are reviewed. Chapter 1 deals with acoustics and psychoacoustics. Chapters 2 and 3 cover cues to spatial hearing and review psychoacoustic literature. Chapter 4 covers signal processing and systems overviews of 3-D sound systems. Chapter 5 covers applications to computer workstations, communication systems, aeronautics and space, and sonic arts. Chapter 6 lists resources. This TM is a reprint of the 1994 book from Academic Press.

Pharmacoinformatics exploration of polyphenol oxidases leading to novel inhibitors by virtual screening and molecular dynamic simulation study.

PubMed

Hassan, Mubashir; Abbas, Qamar; Ashraf, Zaman; Moustafa, Ahmed A; Seo, Sung-Yum

2017-06-01

Polyphenol oxidases (PPOs)/tyrosinases are metal-dependent enzymes and known as important targets for melanogenesis. Although considerable attempts have been conducted to control the melanin-associated diseases by using various inhibitors. However, the exploration of the best anti-melanin inhibitor without side effect still remains a challenge in drug discovery. In present study, protein structure prediction, ligand-based pharmacophore modeling, virtual screening, molecular docking and dynamic simulation study were used to screen the strong novel inhibitor to cure melanogenesis. The 3D structures of PPO1 and PPO2 were built through homology modeling, while the 3D crystal structures of PPO3 and PPO4 were retrieved from PDB. Pharmacophore modeling was performed using LigandScout 3.1 software and top five models were selected to screen the libraries (2601 of Aurora and 727, 842 of ZINC). Top 10 hit compounds (C1-10) were short-listed having strong binding affinities for PPO1-4. Drug and synthetic accessibility (SA) scores along with absorption, distribution, metabolism, excretion and toxicity (ADMET) assessment were employed to scrutinize the best lead hit. C4 (name) hit showed the best predicted SA score (5.75), ADMET properties and drug-likeness behavior among the short-listed compounds. Furthermore, docking simulations were performed to check the binding affinity of C1-C10 compounds against target proteins (PPOs). The binding affinity values of complex between C4 and PPOs were higher than those of other complexes (-11.70, -12.1, -9.90 and -11.20kcal/mol with PPO1, PPO2, PPO3, or PPO4, respectively). From comparative docking energy and binding analyses, PPO2 may be considered as better target for melanogenesis than others. The potential binding modes of C4, C8 and C10 against PPO2 were explored using molecular dynamics simulations. The root mean square deviation and fluctuation (RMSD/RMSF) graphs results depict the significance of C4 over the other compounds. Overall, bioactivity and ligand efficiency profiles suggested that the proposed hit may be more effective inhibitors for melanogenesis. Copyright © 2017 Elsevier Ltd. All rights reserved.

Virtual animation of victim-specific 3D models obtained from CT scans for forensic reconstructions: Living and dead subjects.

PubMed

Villa, C; Olsen, K B; Hansen, S H

2017-09-01

Post-mortem CT scanning (PMCT) has been introduced at several forensic medical institutions many years ago and has proved to be a useful tool. 3D models of bones, skin, internal organs and bullet paths can rapidly be generated using post-processing software. These 3D models reflect the individual physiognomics and can be used to create whole-body 3D virtual animations. In such way, virtual reconstructions of the probable ante-mortem postures of victims can be constructed and contribute to understand the sequence of events. This procedure is demonstrated in two victims of gunshot injuries. Case #1 was a man showing three perforating gunshot wounds, who died due to the injuries of the incident. Whole-body PMCT was performed and 3D reconstructions of bones, relevant internal organs and bullet paths were generated. Using 3ds Max software and a human anatomy 3D model, a virtual animated body was built and probable ante-mortem postures visualized. Case #2 was a man presenting three perforating gunshot wounds, who survived the incident: one in the left arm and two in the thorax. Only CT scans of the thorax, abdomen and the injured arm were provided by the hospital. Therefore, a whole-body 3D model reflecting the anatomical proportions of the patient was made combining the actual bones of the victim with those obtained from the human anatomy 3D model. The resulted 3D model was used for the animation process. Several probable postures were also visualized in this case. It has be shown that in Case #1 the lesions and the bullet path were not consistent with an upright standing position; instead, the victim was slightly bent forward, i.e. he was sitting or running when he was shot. In Case #2, one of the bullets could have passed through the arm and continued into the thorax. In conclusion, specialized 3D modelling and animation techniques allow for the reconstruction of ante-mortem postures based on both PMCT and clinical CT. Copyright © 2017 Elsevier B.V. All rights reserved.

Utilising E-on Vue and Unity 3D scenes to generate synthetic images and videos for visible signature analysis

NASA Astrophysics Data System (ADS)

Madden, Christopher S.; Richards, Noel J.; Culpepper, Joanne B.

2016-10-01

This paper investigates the ability to develop synthetic scenes in an image generation tool, E-on Vue, and a gaming engine, Unity 3D, which can be used to generate synthetic imagery of target objects across a variety of conditions in land environments. Developments within these tools and gaming engines have allowed the computer gaming industry to dramatically enhance the realism of the games they develop; however they utilise short cuts to ensure that the games run smoothly in real-time to create an immersive effect. Whilst these short cuts may have an impact upon the realism of the synthetic imagery, they do promise a much more time efficient method of developing imagery of different environmental conditions and to investigate the dynamic aspect of military operations that is currently not evaluated in signature analysis. The results presented investigate how some of the common image metrics used in target acquisition modelling, namely the Δμ1, Δμ2, Δμ3, RSS, and Doyle metrics, perform on the synthetic scenes generated by E-on Vue and Unity 3D compared to real imagery of similar scenes. An exploration of the time required to develop the various aspects of the scene to enhance its realism are included, along with an overview of the difficulties associated with trying to recreate specific locations as a virtual scene. This work is an important start towards utilising virtual worlds for visible signature evaluation, and evaluating how equivalent synthetic imagery is to real photographs.

Extension of the Optimized Virtual Fields Method to estimate viscoelastic material parameters from 3D dynamic displacement fields

PubMed Central

Connesson, N.; Clayton, E.H.; Bayly, P.V.; Pierron, F.

2015-01-01

In-vivo measurement of the mechanical properties of soft tissues is essential to provide necessary data in biomechanics and medicine (early cancer diagnosis, study of traumatic brain injuries, etc.). Imaging techniques such as Magnetic Resonance Elastography (MRE) can provide 3D displacement maps in the bulk and in vivo, from which, using inverse methods, it is then possible to identify some mechanical parameters of the tissues (stiffness, damping etc.). The main difficulties in these inverse identification procedures consist in dealing with the pressure waves contained in the data and with the experimental noise perturbing the spatial derivatives required during the processing. The Optimized Virtual Fields Method (OVFM) [1], designed to be robust to noise, present natural and rigorous solution to deal with these problems. The OVFM has been adapted to identify material parameter maps from Magnetic Resonance Elastography (MRE) data consisting of 3-dimensional displacement fields in harmonically loaded soft materials. In this work, the method has been developed to identify elastic and viscoelastic models. The OVFM sensitivity to spatial resolution and to noise has been studied by analyzing 3D analytically simulated displacement data. This study evaluates and describes the OVFM identification performances: different biases on the identified parameters are induced by the spatial resolution and experimental noise. The well-known identification problems in the case of quasi-incompressible materials also find a natural solution in the OVFM. Moreover, an a posteriori criterion to estimate the local identification quality is proposed. The identification results obtained on actual experiments are briefly presented. PMID:26146416

A Second Chance at Health: How a 3D Virtual World Can Improve Health Self-Efficacy for Weight Loss Management Among Adults.

PubMed

Behm-Morawitz, Elizabeth; Lewallen, Jennifer; Choi, Grace

2016-02-01

Health self-efficacy, or the beliefs in one's capabilities to perform health behaviors, is a significant factor in eliciting health behavior change, such as weight loss. Research has demonstrated that virtual embodiment has the potential to alter one's psychology and physicality, particularly in health contexts; however, little is known about the impacts embodiment in a virtual world has on health self-efficacy. The present research is a randomized controlled trial (N = 90) examining the effectiveness of virtual embodiment and play in a social virtual world (Second Life [SL]) for increasing health self-efficacy (exercise and nutrition efficacy) among overweight adults. Participants were randomly assigned to a 3D social virtual world (avatar virtual interaction experimental condition), 2D social networking site (no avatar virtual interaction control condition), or no intervention (no virtual interaction control condition). The findings of this study provide initial evidence for the use of SL to improve exercise efficacy and to support weight loss. Results also suggest that individuals who have higher self-presence with their avatar reap more benefits. Finally, quantitative findings are triangulated with qualitative data to increase confidence in the results and provide richer insight into the perceived effectiveness and limitations of SL for meeting weight loss goals. Themes resulting from the qualitative analysis indicate that participation in SL can improve motivation and efficacy to try new physical activities; however, individuals who have a dislike for video games may not be benefitted by avatar-based virtual interventions. Implications for research on the transformative potential of virtual embodiment and self-presence in general are discussed.

[Preliminary safety and stability assessment of orthodontic miniscrew implantation guided by surgical template based on cone-beam CT images].

PubMed

Qiu, L L; Li, S; Bai, Y X

2016-06-01

To develop surgical templates for orthodontic miniscrew implantation based on cone-beam CT(CBCT)three-dimensional(3D)images and to evaluate the safety and stability of implantation guided by the templates. DICOM data obtained in patients who had CBCT scans taken were processed using Mimics software, and 3D images of teeth and maxillary bone were acquired. Meanwhile, 3D images of miniscrews were acquired using Solidworks software and processed with Mimics software. Virtual position of miniscrews was determined based on 3D images of teeth, bone, and miniscrews. 3D virtual templates were designed according to the virtual implantation plans. STL files were output and the real templates were fabricated with stereolithographic appliance(SLA). Postoperative CBCT scans were used to evaluate the implantation safety and the stability of miniscrews were investigated. All the templates were positioned accurately and kept stable throughout the implantation process. No root damage was found. The deviations were(1.73±0.65)mm at the corona, and(1.28±0.82)mm at the apex, respectively. The stability of miniscrews was fairly well. Surgical templates for miniscrew implantation could be acquired based on 3D CBCT images and fabricated with SLA. Implantation guided by these templates was safe and stable.

A Learner-Centered Approach for Training Science Teachers through Virtual Reality and 3D Visualization Technologies: Practical Experience for Sharing

ERIC Educational Resources Information Center

Yeung, Yau-Yuen

2004-01-01

This paper presentation will report on how some science educators at the Science Department of The Hong Kong Institute of Education have successfully employed an array of innovative learning media such as three-dimensional (3D) and virtual reality (VR) technologies to create seven sets of resource kits, most of which are being placed on the…

Design and Implementation of a 3D Multi-User Virtual World for Language Learning

ERIC Educational Resources Information Center

Ibanez, Maria Blanca; Garcia, Jose Jesus; Galan, Sergio; Maroto, David; Morillo, Diego; Kloos, Carlos Delgado

2011-01-01

The best way to learn is by having a good teacher and the best language learning takes place when the learner is immersed in an environment where the language is natively spoken. 3D multi-user virtual worlds have been claimed to be useful for learning, and the field of exploiting them for education is becoming more and more active thanks to the…

The cognitive apprenticeship theory for the teaching of mathematics in an online 3D virtual environment

NASA Astrophysics Data System (ADS)

Bouta, Hara; Paraskeva, Fotini

2013-03-01

Research spanning two decades shows that there is a continuing development of 3D virtual worlds and investment in such environments for educational purposes. Research stresses the need for these environments to be well-designed and for suitable pedagogies to be implemented in the teaching practice in order for these worlds to be fully effective. To this end, we propose a pedagogical framework based on the cognitive apprenticeship for deriving principles and guidelines to inform the design, development and use of a 3D virtual environment. This study examines how the use of a 3D virtual world facilitates the teaching of mathematics in primary education by combining design principles and guidelines based on the Cognitive Apprenticeship Theory and the teaching methods that this theory introduces. We focus specifically on 5th and 6th grade students' engagement (behavioral, affective and cognitive) while learning fractional concepts over a period of two class sessions. Quantitative and qualitative analyses indicate considerable improvement in the engagement of the students who participated in the experiment. This paper presents the findings regarding students' cognitive engagement in the process of comprehending basic fractional concepts - notoriously hard for students to master. The findings are encouraging and suggestions are made for further research.

Virtual reality system for planning minimally invasive neurosurgery. Technical note.

PubMed

Stadie, Axel Thomas; Kockro, Ralf Alfons; Reisch, Robert; Tropine, Andrei; Boor, Stephan; Stoeter, Peter; Perneczky, Axel

2008-02-01

The authors report on their experience with a 3D virtual reality system for planning minimally invasive neurosurgical procedures. Between October 2002 and April 2006, the authors used the Dextroscope (Volume Interactions, Ltd.) to plan neurosurgical procedures in 106 patients, including 100 with intracranial and 6 with spinal lesions. The planning was performed 1 to 3 days preoperatively, and in 12 cases, 3D prints of the planning procedure were taken into the operating room. A questionnaire was completed by the neurosurgeon after the planning procedure. After a short period of acclimatization, the system proved easy to operate and is currently used routinely for preoperative planning of difficult cases at the authors' institution. It was felt that working with a virtual reality multimodal model of the patient significantly improved surgical planning. The pathoanatomy in individual patients could easily be understood in great detail, enabling the authors to determine the surgical trajectory precisely and in the most minimally invasive way. The authors found the preoperative 3D model to be in high concordance with intraoperative conditions; the resulting intraoperative "déjà-vu" feeling enhanced surgical confidence. In all procedures planned with the Dextroscope, the chosen surgical strategy proved to be the correct choice. Three-dimensional virtual reality models of a patient allow quick and easy understanding of complex intracranial lesions.

Seamless 3D interaction for virtual tables, projection planes, and CAVEs

NASA Astrophysics Data System (ADS)

Encarnacao, L. M.; Bimber, Oliver; Schmalstieg, Dieter; Barton, Robert J., III

2000-08-01

The Virtual Table presents stereoscopic graphics to a user in a workbench-like setting. This device shares with other large- screen display technologies (such as data walls and surround- screen projection systems) the lack of human-centered unencumbered user interfaces and 3D interaction technologies. Such shortcomings present severe limitations to the application of virtual reality (VR) technology to time- critical applications as well as employment scenarios that involve heterogeneous groups of end-users without high levels of computer familiarity and expertise. Traditionally such employment scenarios are common in planning-related application areas such as mission rehearsal and command and control. For these applications, a high grade of flexibility with respect to the system requirements (display and I/O devices) as well as to the ability to seamlessly and intuitively switch between different interaction modalities and interaction are sought. Conventional VR techniques may be insufficient to meet this challenge. This paper presents novel approaches for human-centered interfaces to Virtual Environments focusing on the Virtual Table visual input device. It introduces new paradigms for 3D interaction in virtual environments (VE) for a variety of application areas based on pen-and-clipboard, mirror-in-hand, and magic-lens metaphors, and introduces new concepts for combining VR and augmented reality (AR) techniques. It finally describes approaches toward hybrid and distributed multi-user interaction environments and concludes by hypothesizing on possible use cases for defense applications.

Effectiveness of Collaborative Learning with 3D Virtual Worlds

ERIC Educational Resources Information Center

Cho, Young Hoan; Lim, Kenneth Y. T.

2017-01-01

Virtual worlds have affordances to enhance collaborative learning in authentic contexts. Despite the potential of collaborative learning with a virtual world, few studies investigated whether it is more effective in student achievements than teacher-directed instruction. This study investigated the effectiveness of collaborative problem solving…

[3D Virtual Reality Laparoscopic Simulation in Surgical Education - Results of a Pilot Study].

PubMed

Kneist, W; Huber, T; Paschold, M; Lang, H

2016-06-01

The use of three-dimensional imaging in laparoscopy is a growing issue and has led to 3D systems in laparoscopic simulation. Studies on box trainers have shown differing results concerning the benefit of 3D imaging. There are currently no studies analysing 3D imaging in virtual reality laparoscopy (VRL). Five surgical fellows, 10 surgical residents and 29 undergraduate medical students performed abstract and procedural tasks on a VRL simulator using conventional 2D and 3D imaging in a randomised order. No significant differences between the two imaging systems were shown for students or medical professionals. Participants who preferred three-dimensional imaging showed significantly better results in 2D as wells as in 3D imaging. First results on three-dimensional imaging on box trainers showed different results. Some studies resulted in an advantage of 3D imaging for laparoscopic novices. This study did not confirm the superiority of 3D imaging over conventional 2D imaging in a VRL simulator. In the present study on 3D imaging on a VRL simulator there was no significant advantage for 3D imaging compared to conventional 2D imaging. Georg Thieme Verlag KG Stuttgart · New York.

Integration of computer-assisted fracture reduction system and a hybrid 3-DOF-RPS mechanism for assisting the orthopedic surgery

NASA Astrophysics Data System (ADS)

Irwansyah; Sinh, N. P.; Lai, J. Y.; Essomba, T.; Asbar, R.; Lee, P. Y.

2018-02-01

In this paper, we present study to integrate virtual fracture bone reduction simulation tool with a novel hybrid 3-DOF-RPS external fixator to relocate back bone fragments into their anatomically original position. A 3D model of fractured bone was reconstructed and manipulated using 3D design and modeling software, PhysiGuide. The virtual reduction system was applied to reduce a bilateral femoral shaft fracture type 32-A3. Measurement data from fracture reduction and fixation stages were implemented to manipulate the manipulator pose in patient’s clinical case. The experimental result presents that by merging both of those techniques will give more possibilities to reduce virtual bone reduction time, improve facial and shortest healing treatment.

Conventional plate fixation method versus pre-operative virtual simulation and three-dimensional printing-assisted contoured plate fixation method in the treatment of anterior pelvic ring fracture.

PubMed

Hung, Chun-Chi; Li, Yuan-Ta; Chou, Yu-Ching; Chen, Jia-En; Wu, Chia-Chun; Shen, Hsain-Chung; Yeh, Tsu-Te

2018-05-03

Treating pelvic fractures remains a challenging task for orthopaedic surgeons. We aimed to evaluate the feasibility, accuracy, and effectiveness of three-dimensional (3D) printing technology and computer-assisted virtual surgery for pre-operative planning in anterior ring fractures of the pelvis. We hypothesized that using 3D printing models would reduce operation time and significantly improve the surgical outcomes of pelvic fracture repair. We retrospectively reviewed the records of 30 patients with pelvic fractures treated by anterior pelvic fixation with locking plates (14 patients, conventional locking plate fixation; 16 patients, pre-operative virtual simulation with 3D, printing-assisted, pre-contoured, locking plate fixation). We compared operative time, instrumentation time, blood loss, and post-surgical residual displacements, as evaluated on X-ray films, among groups. Statistical analyses evaluated significant differences between the groups for each of these variables. The patients treated with the virtual simulation and 3D printing-assisted technique had significantly shorter internal fixation times, shorter surgery duration, and less blood loss (- 57 minutes, - 70 minutes, and - 274 ml, respectively; P < 0.05) than patients in the conventional surgery group. However, the post-operative radiological result was similar between groups (P > 0.05). The complication rate was less in the 3D printing group (1/16 patients) than in the conventional surgery group (3/14 patients). The 3D simulation and printing technique is an effective and reliable method for treating anterior pelvic ring fractures. With precise pre-operative planning and accurate execution of the procedures, this time-saving approach can provide a more personalized treatment plan, allowing for a safer orthopaedic surgery.

Taking Science Online: Evaluating Presence and Immersion through a Laboratory Experience in a Virtual Learning Environment for Entomology Students

ERIC Educational Resources Information Center

Annetta, Leonard; Klesath, Marta; Meyer, John

2009-01-01

A 3-D virtual field trip was integrated into an online college entomology course and developed as a trial for the possible incorporation of future virtual environments to supplement online higher education laboratories. This article provides an explanation of the rationale behind creating the virtual experience, the Bug Farm; the method and…

Developing a Second Life Virtual Field Trip for University Students: An Action Research Approach

ERIC Educational Resources Information Center

Mathews, Shane; Andrews, Lynda; Luck, Edwina

2012-01-01

Background: Integrating 3D virtual world technologies into educational subjects continues to draw the attention of educators and researchers alike. The focus of this study is the use of a virtual world, Second Life, in higher education teaching. In particular, it explores the potential of using a virtual world experience as a learning component…

The Use of Virtual Ethnography in Distance Education Research

ERIC Educational Resources Information Center

Uzun, Kadriye; Aydin, Cengiz Hakan

2012-01-01

3D virtual worlds can and have been used as a meeting place for distance education courses. Virtual worlds allow for group learning of the kind enjoyed by students gathered in a virtual classroom, where they know they are in a communal space, they are aware of the social process of learning and are affected by the presence and behaviour of their…

Computer tomography prototyping and virtual procedure simulation in difficult cases of hip replacement surgery.

PubMed

Parchi, Paolo Domenico; Ferrari, Vincenzo; Piolanti, Nicola; Andreani, Lorenzo; Condino, Sara; Evangelisti, Gisberto; Lisanti, Michele

2013-09-01

Each year approximately 1 million total hip replacements (THR) are performed worldwide. A percentage of failure due to surgical approach and imprecise implant placement still exists. These result in several serious complications. We propose an approach to plan, to simulate, and to assist prosthesis implantation for difficult cases of THR based on 3-D virtual models, generated by segmenting patients' CT images, 3-D solid models, obtained by rapid prototyping (RP), and virtual procedure simulation. We carried out 8 THR with the aid of 3-D reconstruction and RP. After each procedure a questionnaire was submitted to the surgeon to assess the perceived added value of the technology. In all cases, the surgeon evaluated the 3-D model as useful in order to perform the planning. The clinical results showed a mean increase in the Harris Hip Score of about 42.5 points. The mean time of prototyping was 7.3 hours, (min 3.5 hours, max 9.3 hours). The mean surgery time was 65 minutes (min 50 minutes, max 88 minutes). Our study suggests that meticulous preoperative planning is necessary in front of a great aberration of the joint and in absence of normal anatomical landmarks, CT scan is mandatory, and 3-D reconstruction with solid model is useful.

Virtual Modeling for Cities of the Future. State-Of Art and Virtual Modeling for Cities of the Future. State-Of Art AN

NASA Astrophysics Data System (ADS)

Valencia, J.; Muñoz-Nieto, A.; Rodriguez-Gonzalvez, P.

2015-02-01

3D virtual modeling, visualization, dissemination and management of urban areas is one of the most exciting challenges that must face geomatics in the coming years. This paper aims to review, compare and analyze the new technologies, policies and software tools that are in progress to manage urban 3D information. It is assumed that the third dimension increases the quality of the model provided, allowing new approaches to urban planning, conservation and management of architectural and archaeological areas. Despite the fact that displaying 3D urban environments is an issue nowadays solved, there are some challenges to be faced by geomatics in the coming future. Displaying georeferenced linked information would be considered the first challenge. Another challenge to face is to improve the technical requirements if this georeferenced information must be shown in real time. Are there available software tools ready for this challenge? Are they useful to provide services required in smart cities? Throughout this paper, many practical examples that require 3D georeferenced information and linked data will be shown. Computer advances related to 3D spatial databases and software that are being developed to convert rendering virtual environment to a new enriched environment with linked information will be also analyzed. Finally, different standards that Open Geospatial Consortium has assumed and developed regarding the three-dimensional geographic information will be reviewed. Particular emphasis will be devoted on KML, LandXML, CityGML and the new IndoorGML.

Analyzing Visitors' Discourse, Attitudes, Perceptions, and Knowledge Acquisition in an Art Museum Tour after Using a 3D Virtual Environment

ERIC Educational Resources Information Center

D'Alba, Adriana

2012-01-01

The main purpose of this mixed methods research was to explore and analyze visitors' overall experience while they attended a museum exhibition, and examine how this experience was affected by previously using a virtual 3dimensional representation of the museum itself. The research measured knowledge acquisition in a virtual museum, and compared…

Insights into unbound-bound states of GPR142 receptor in a membrane-aqueous system using molecular dynamics simulations.

PubMed

Kaushik, Aman Chandra; Sahi, Shakti

2018-05-01

G protein coupled receptors (GPCRs) are source machinery in signal transduction pathways and being one of the major therapeutic targets play a significant in drug discovery. GPR142, an orphan GPCR, has been implicated in the regulation of insulin, thereby having a crucial role in Type II diabetes management. Deciphering of the structures of orphan, GPCRs (O-GPCRs) offer better prospects for advancements in research in ion translocation and transduction of extracellular signals. As the crystallographic structure of GPR142 is not available in PDB, therefore, threading and ab initio-based approaches were used for 3D modeling of GPR142. Molecular dynamic simulations (900 ns) were performed on the 3D model of GPR142 and complexes of GPR142 with top five hits, obtained through virtual screening, embedded in lipid bilayer with aqueous system using OPLS force field. Compound 1, 3, and 4 may act as scaffolds for designing potential lead agonists for GPR142. The finding of GPR142 MD simulation study provides more comprehensive representation of the functional properties. The concern for Type II diabetes is increasing worldwide and successful treatment of this disease demands novel drugs with better efficacy.

Dynamic Extension of a Virtualized Cluster by using Cloud Resources

NASA Astrophysics Data System (ADS)

Oberst, Oliver; Hauth, Thomas; Kernert, David; Riedel, Stephan; Quast, Günter

2012-12-01

The specific requirements concerning the software environment within the HEP community constrain the choice of resource providers for the outsourcing of computing infrastructure. The use of virtualization in HPC clusters and in the context of cloud resources is therefore a subject of recent developments in scientific computing. The dynamic virtualization of worker nodes in common batch systems provided by ViBatch serves each user with a dynamically virtualized subset of worker nodes on a local cluster. Now it can be transparently extended by the use of common open source cloud interfaces like OpenNebula or Eucalyptus, launching a subset of the virtual worker nodes within the cloud. This paper demonstrates how a dynamically virtualized computing cluster is combined with cloud resources by attaching remotely started virtual worker nodes to the local batch system.

C-arm positioning using virtual fluoroscopy for image-guided surgery

NASA Astrophysics Data System (ADS)

de Silva, T.; Punnoose, J.; Uneri, A.; Goerres, J.; Jacobson, M.; Ketcha, M. D.; Manbachi, A.; Vogt, S.; Kleinszig, G.; Khanna, A. J.; Wolinsky, J.-P.; Osgood, G.; Siewerdsen, J. H.

2017-03-01

Introduction: Fluoroscopically guided procedures often involve repeated acquisitions for C-arm positioning at the cost of radiation exposure and time in the operating room. A virtual fluoroscopy system is reported with the potential of reducing dose and time spent in C-arm positioning, utilizing three key advances: robust 3D-2D registration to a preoperative CT; real-time forward projection on GPU; and a motorized mobile C-arm with encoder feedback on C-arm orientation. Method: Geometric calibration of the C-arm was performed offline in two rotational directions (orbit α, orbit β). Patient registration was performed using image-based 3D-2D registration with an initially acquired radiograph of the patient. This approach for patient registration eliminated the requirement for external tracking devices inside the operating room, allowing virtual fluoroscopy using commonly available systems in fluoroscopically guided procedures within standard surgical workflow. Geometric accuracy was evaluated in terms of projection distance error (PDE) in anatomical fiducials. A pilot study was conducted to evaluate the utility of virtual fluoroscopy to aid C-arm positioning in image guided surgery, assessing potential improvements in time, dose, and agreement between the virtual and desired view. Results: The overall geometric accuracy of DRRs in comparison to the actual radiographs at various C-arm positions was PDE (mean ± std) = 1.6 ± 1.1 mm. The conventional approach required on average 8.0 ± 4.5 radiographs spent "fluoro hunting" to obtain the desired view. Positioning accuracy improved from 2.6o ± 2.3o (in α) and 4.1o ± 5.1o (in β) in the conventional approach to 1.5o ± 1.3o and 1.8o ± 1.7o, respectively, with the virtual fluoroscopy approach. Conclusion: Virtual fluoroscopy could improve accuracy of C-arm positioning and save time and radiation dose in the operating room. Such a system could be valuable to training of fluoroscopy technicians as well as intraoperative use in fluoroscopically guided procedures.

Virtual Reconstruction and Three-Dimensional Printing of Blood Cells as a Tool in Cell Biology Education.

PubMed

Augusto, Ingrid; Monteiro, Douglas; Girard-Dias, Wendell; Dos Santos, Thaisa Oliveira; Rosa Belmonte, Simone Letícia; Pinto de Oliveira, Jairo; Mauad, Helder; da Silva Pacheco, Marcos; Lenz, Dominik; Stefanon Bittencourt, Athelson; Valentim Nogueira, Breno; Lopes Dos Santos, Jorge Roberto; Miranda, Kildare; Guimarães, Marco Cesar Cunegundes

2016-01-01

The cell biology discipline constitutes a highly dynamic field whose concepts take a long time to be incorporated into the educational system, especially in developing countries. Amongst the main obstacles to the introduction of new cell biology concepts to students is their general lack of identification with most teaching methods. The introduction of elaborated figures, movies and animations to textbooks has given a tremendous contribution to the learning process and the search for novel teaching methods has been a central goal in cell biology education. Some specialized tools, however, are usually only available in advanced research centers or in institutions that are traditionally involved with the development of novel teaching/learning processes, and are far from becoming reality in the majority of life sciences schools. When combined with the known declining interest in science among young people, a critical scenario may result. This is especially important in the field of electron microscopy and associated techniques, methods that have greatly contributed to the current knowledge on the structure and function of different cell biology models but are rarely made accessible to most students. In this work, we propose a strategy to increase the engagement of students into the world of cell and structural biology by combining 3D electron microscopy techniques and 3D prototyping technology (3D printing) to generate 3D physical models that accurately and realistically reproduce a close-to-the native structure of the cell and serve as a tool for students and teachers outside the main centers. We introduce three strategies for 3D imaging, modeling and prototyping of cells and propose the establishment of a virtual platform where different digital models can be deposited by EM groups and subsequently downloaded and printed in different schools, universities, research centers and museums, thereby modernizing teaching of cell biology and increasing the accessibility to modern approaches in basic science.

Virtual Reconstruction and Three-Dimensional Printing of Blood Cells as a Tool in Cell Biology Education

PubMed Central

Girard-Dias, Wendell; dos Santos, Thaisa Oliveira; Rosa Belmonte, Simone Letícia; Pinto de Oliveira, Jairo; Mauad, Helder; da Silva Pacheco, Marcos; Lenz, Dominik; Stefanon Bittencourt, Athelson; Valentim Nogueira, Breno; Lopes dos Santos, Jorge Roberto; Miranda, Kildare; Guimarães, Marco Cesar Cunegundes

2016-01-01

The cell biology discipline constitutes a highly dynamic field whose concepts take a long time to be incorporated into the educational system, especially in developing countries. Amongst the main obstacles to the introduction of new cell biology concepts to students is their general lack of identification with most teaching methods. The introduction of elaborated figures, movies and animations to textbooks has given a tremendous contribution to the learning process and the search for novel teaching methods has been a central goal in cell biology education. Some specialized tools, however, are usually only available in advanced research centers or in institutions that are traditionally involved with the development of novel teaching/learning processes, and are far from becoming reality in the majority of life sciences schools. When combined with the known declining interest in science among young people, a critical scenario may result. This is especially important in the field of electron microscopy and associated techniques, methods that have greatly contributed to the current knowledge on the structure and function of different cell biology models but are rarely made accessible to most students. In this work, we propose a strategy to increase the engagement of students into the world of cell and structural biology by combining 3D electron microscopy techniques and 3D prototyping technology (3D printing) to generate 3D physical models that accurately and realistically reproduce a close-to-the native structure of the cell and serve as a tool for students and teachers outside the main centers. We introduce three strategies for 3D imaging, modeling and prototyping of cells and propose the establishment of a virtual platform where different digital models can be deposited by EM groups and subsequently downloaded and printed in different schools, universities, research centers and museums, thereby modernizing teaching of cell biology and increasing the accessibility to modern approaches in basic science. PMID:27526196

2D virtual texture on 3D real object with coded structured light

NASA Astrophysics Data System (ADS)

Molinier, Thierry; Fofi, David; Salvi, Joaquim; Gorria, Patrick

2008-02-01

Augmented reality is used to improve color segmentation on human body or on precious no touch artifacts. We propose a technique to project a synthesized texture on real object without contact. Our technique can be used in medical or archaeological application. By projecting a suitable set of light patterns onto the surface of a 3D real object and by capturing images with a camera, a large number of correspondences can be found and the 3D points can be reconstructed. We aim to determine these points of correspondence between cameras and projector from a scene without explicit points and normals. We then project an adjusted texture onto the real object surface. We propose a global and automatic method to virtually texture a 3D real object.

Wave Field Synthesis of moving sources with arbitrary trajectory and velocity profile.

PubMed

Firtha, Gergely; Fiala, Péter

2017-08-01

The sound field synthesis of moving sound sources is of great importance when dynamic virtual sound scenes are to be reconstructed. Previous solutions considered only virtual sources moving uniformly along a straight trajectory, synthesized employing a linear loudspeaker array. This article presents the synthesis of point sources following an arbitrary trajectory. Under high-frequency assumptions 2.5D Wave Field Synthesis driving functions are derived for arbitrary shaped secondary source contours by adapting the stationary phase approximation to the dynamic description of sources in motion. It is explained how a referencing function should be chosen in order to optimize the amplitude of synthesis on an arbitrary receiver curve. Finally, a finite difference implementation scheme is considered, making the presented approach suitable for real-time applications.

Virtual exertions: evoking the sense of exerting forces in virtual reality using gestures and muscle activity.

PubMed

Chen, Karen B; Ponto, Kevin; Tredinnick, Ross D; Radwin, Robert G

2015-06-01

This study was a proof of concept for virtual exertions, a novel method that involves the use of body tracking and electromyography for grasping and moving projections of objects in virtual reality (VR). The user views objects in his or her hands during rehearsed co-contractions of the same agonist-antagonist muscles normally used for the desired activities to suggest exerting forces. Unlike physical objects, virtual objects are images and lack mass. There is currently no practical physically demanding way to interact with virtual objects to simulate strenuous activities. Eleven participants grasped and lifted similar physical and virtual objects of various weights in an immersive 3-D Cave Automatic Virtual Environment. Muscle activity, localized muscle fatigue, ratings of perceived exertions, and NASA Task Load Index were measured. Additionally, the relationship between levels of immersion (2-D vs. 3-D) was studied. Although the overall magnitude of biceps activity and workload were greater in VR, muscle activity trends and fatigue patterns for varying weights within VR and physical conditions were the same. Perceived exertions for varying weights were not significantly different between VR and physical conditions. Perceived exertion levels and muscle activity patterns corresponded to the assigned virtual loads, which supported the hypothesis that the method evoked the perception of physical exertions and showed that the method was promising. Ultimately this approach may offer opportunities for research and training individuals to perform strenuous activities under potentially safer conditions that mimic situations while seeing their own body and hands relative to the scene. © 2014, Human Factors and Ergonomics Society.

Large-Scale Networked Virtual Environments: Architecture and Applications

ERIC Educational Resources Information Center

Lamotte, Wim; Quax, Peter; Flerackers, Eddy

2008-01-01

Purpose: Scalability is an important research topic in the context of networked virtual environments (NVEs). This paper aims to describe the ALVIC (Architecture for Large-scale Virtual Interactive Communities) approach to NVE scalability. Design/methodology/approach: The setup and results from two case studies are shown: a 3-D learning environment…

Virtual reality hardware and graphic display options for brain-machine interfaces

PubMed Central

Marathe, Amar R.; Carey, Holle L.; Taylor, Dawn M.

2009-01-01

Virtual reality hardware and graphic displays are reviewed here as a development environment for brain-machine interfaces (BMIs). Two desktop stereoscopic monitors and one 2D monitor were compared in a visual depth discrimination task and in a 3D target-matching task where able-bodied individuals used actual hand movements to match a virtual hand to different target hands. Three graphic representations of the hand were compared: a plain sphere, a sphere attached to the fingertip of a realistic hand and arm, and a stylized pacman-like hand. Several subjects had great difficulty using either stereo monitor for depth perception when perspective size cues were removed. A mismatch in stereo and size cues generated inappropriate depth illusions. This phenomenon has implications for choosing target and virtual hand sizes in BMI experiments. Target matching accuracy was about as good with the 2D monitor as with either 3D monitor. However, users achieved this accuracy by exploring the boundaries of the hand in the target with carefully controlled movements. This method of determining relative depth may not be possible in BMI experiments if movement control is more limited. Intuitive depth cues, such as including a virtual arm, can significantly improve depth perception accuracy with or without stereo viewing. PMID:18006069

Ames Lab 101: osgBullet

ScienceCinema

McCorkle, Doug

2017-12-27

Ames Laboratory scientist Doug McCorkle explains osgBullet, a 3-D virtual simulation software, and how it helps engineers design complex products and systems in a realistic, real-time virtual environment.

A Downloadable Three-Dimensional Virtual Model of the Visible Ear

PubMed Central

Wang, Haobing; Merchant, Saumil N.; Sorensen, Mads S.

2008-01-01

Purpose To develop a three-dimensional (3-D) virtual model of a human temporal bone and surrounding structures. Methods A fresh-frozen human temporal bone was serially sectioned and digital images of the surface of the tissue block were recorded (the ‘Visible Ear’). The image stack was resampled at a final resolution of 50 × 50 × 50/100 µm/voxel, registered in custom software and segmented in PhotoShop® 7.0. The segmented image layers were imported into Amira® 3.1 to generate smooth polygonal surface models. Results The 3-D virtual model presents the structures of the middle, inner and outer ears in their surgically relevant surroundings. It is packaged within a cross-platform freeware, which allows for full rotation, visibility and transparency control, as well as the ability to slice the 3-D model open at any section. The appropriate raw image can be superimposed on the cleavage plane. The model can be downloaded at https://research.meei.harvard.edu/Otopathology/3dmodels/ PMID:17124433

Atmospheric volatilization and distribution of (Z)- and (E)-1,3-dichloropropene in field beds with and without plastic covers.

PubMed

Thomas, John E; Allen, L Hartwell; McCormack, Leslie A; Vu, Joseph C; Dickson, Donald W; Ou, Li-Tse

2004-01-01

The fumigant 1,3-dichloropropene (1,3-D) is considered to be a potential replacement for methyl bromide when methyl bromide is phased out in 2005. This study on surface emissions and subsurface diffusion of 1,3-D in a Florida sandy soil was conducted in field beds with or without plastic covers. After injection of the commercial fumigant Telone II by conventional chisels to field beds at 30cm depth which were covered with polyethylene film (PE), virtually impermeable film, or no cover (bare), (Z)- and (E)-1,3-D rapidly diffused upward. Twenty hours after injection, majority of (Z)- and (E)-1,3-D had moved upward from 30 cm depth to the layer of 5-20 cm depth. Downward movement of the two isomers in the beds with or without a plastic cover was not significant. (Z)-1,3-D diffused more rapidly than (E)-1,3-D. Virtually impermeable films (VIF) had a good capacity to retain (Z)- and (E)-1,3-D in soil pore air space. Vapor concentrations of the two isomers in the shallow subsurface of the field bed covered with VIF were greater than that in the two beds covered with polyethylene film (PE) or no cover (bare). In addition, VIF cover provided more uniform distribution of (Z)- and (E)-1,3-D in shallow subsurface than PE cover or no cover. Virtually impermeable film also had a better capability to retard surface emissions of the two isomers from soil in field beds than PE cover or no cover.

Fostering Verbal and Non-Verbal Social Interactions in a 3D Collaborative Virtual Learning Environment: A Case Study of Youth with Autism Spectrum Disorders Learning Social Competence in iSocial

ERIC Educational Resources Information Center

Wang, Xianhui; Laffey, James; Xing, Wanli; Galyen, Krista; Stichter, Janine

2017-01-01

This case study describes the verbal and nonverbal social interaction of 11 youth with Autism Spectrum Disorders in a 3D Collaborative Virtual Learning Environment-iSocial. The youth were developing social competence through participation in a social competence intervention curriculum implemented online so as to provide access to high quality…

Using virtual reality technology and hand tracking technology to create software for training surgical skills in 3D game

NASA Astrophysics Data System (ADS)

Zakirova, A. A.; Ganiev, B. A.; Mullin, R. I.

2015-11-01

The lack of visible and approachable ways of training surgical skills is one of the main problems in medical education. Existing simulation training devices are not designed to teach students, and are not available due to the high cost of the equipment. Using modern technologies such as virtual reality and hands movements fixation technology we want to create innovative method of learning the technics of conducting operations in 3D game format, which can make education process interesting and effective. Creating of 3D format virtual simulator will allow to solve several conceptual problems at once: opportunity of practical skills improvement unlimited by the time without the risk for patient, high realism of environment in operational and anatomic body structures, using of game mechanics for information perception relief and memorization of methods acceleration, accessibility of this program.

Encountered-Type Haptic Interface for Representation of Shape and Rigidity of 3D Virtual Objects.

PubMed

Takizawa, Naoki; Yano, Hiroaki; Iwata, Hiroo; Oshiro, Yukio; Ohkohchi, Nobuhiro

2017-01-01

This paper describes the development of an encountered-type haptic interface that can generate the physical characteristics, such as shape and rigidity, of three-dimensional (3D) virtual objects using an array of newly developed non-expandable balloons. To alter the rigidity of each non-expandable balloon, the volume of air in it is controlled through a linear actuator and a pressure sensor based on Hooke's law. Furthermore, to change the volume of each balloon, its exposed surface area is controlled by using another linear actuator with a trumpet-shaped tube. A position control mechanism is constructed to display virtual objects using the balloons. The 3D position of each balloon is controlled using a flexible tube and a string. The performance of the system is tested and the results confirm the effectiveness of the proposed principle and interface.

Research-Grade 3D Virtual Astromaterials Samples: Novel Visualization of NASA's Apollo Lunar Samples and Antarctic Meteorite Samples to Benefit Curation, Research, and Education

NASA Technical Reports Server (NTRS)

Blumenfeld, E. H.; Evans, C. A.; Oshel, E. R.; Liddle, D. A.; Beaulieu, K. R.; Zeigler, R. A.; Righter, K.; Hanna, R. D.; Ketcham, R. A.

2017-01-01

NASA's vast and growing collections of astromaterials are both scientifically and culturally significant, requiring unique preservation strategies that need to be recurrently updated to contemporary technological capabilities and increasing accessibility demands. New technologies have made it possible to advance documentation and visualization practices that can enhance conservation and curation protocols for NASA's Astromaterials Collections. Our interdisciplinary team has developed a method to create 3D Virtual Astromaterials Samples (VAS) of the existing collections of Apollo Lunar Samples and Antarctic Meteorites. Research-grade 3D VAS will virtually put these samples in the hands of researchers and educators worldwide, increasing accessibility and visibility of these significant collections. With new sample return missions on the horizon, it is of primary importance to develop advanced curation standards for documentation and visualization methodologies.

Sexual affordances, perceptual-motor invariance extraction and intentional nonlinear dynamics: sexually deviant and non-deviant patterns in male subjects.

PubMed

Renaud, Patrice; Goyette, Mathieu; Chartier, Sylvain; Zhornitski, Simon; Trottier, Dominique; Rouleau, Joanne-L; Proulx, Jean; Fedoroff, Paul; Bradford, John-P; Dassylva, Benoit; Bouchard, Stephane

2010-10-01

Sexual arousal and gaze behavior dynamics are used to characterize deviant sexual interests in male subjects. Pedophile patients and non-deviant subjects are immersed with virtual characters depicting relevant sexual features. Gaze behavior dynamics as indexed from correlation dimensions (D2) appears to be fractal in nature and significantly different from colored noise (surrogate data tests and recurrence plot analyses were performed). This perceptual-motor fractal dynamics parallels sexual arousal and differs from pedophiles to non-deviant subjects when critical sexual information is processed. Results are interpreted in terms of sexual affordance, perceptual invariance extraction and intentional nonlinear dynamics.

Use of the stereoscopic virtual reality display system for the detection and characterization of intracranial aneurysms: A Icomparison with conventional computed tomography workstation and 3D rotational angiography.

PubMed

Liu, Xiujuan; Tao, Haiquan; Xiao, Xigang; Guo, Binbin; Xu, Shangcai; Sun, Na; Li, Maotong; Xie, Li; Wu, Changjun

2018-07-01

This study aimed to compare the diagnostic performance of the stereoscopic virtual reality display system with the conventional computed tomography (CT) workstation and three-dimensional rotational angiography (3DRA) for intracranial aneurysm detection and characterization, with a focus on small aneurysms and those near the bone. First, 42 patients with suspected intracranial aneurysms underwent both 256-row CT angiography (CTA) and 3DRA. Volume rendering (VR) images were captured using the conventional CT workstation. Next, VR images were transferred to the stereoscopic virtual reality display system. Two radiologists independently assessed the results that were obtained using the conventional CT workstation and stereoscopic virtual reality display system. The 3DRA results were considered as the ultimate reference standard. Based on 3DRA images, 38 aneurysms were confirmed in 42 patients. Two cases were misdiagnosed and 1 was missed when the traditional CT workstation was used. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of the conventional CT workstation were 94.7%, 85.7%, 97.3%, 75%, and99.3%, respectively, on a per-aneurysm basis. The stereoscopic virtual reality display system missed a case. The sensitivity, specificity, PPV, NPV, and accuracy of the stereoscopic virtual reality display system were 100%, 85.7%, 97.4%, 100%, and 97.8%, respectively. No difference was observed in the accuracy of the traditional CT workstation, stereoscopic virtual reality display system, and 3DRA in detecting aneurysms. The stereoscopic virtual reality display system has some advantages in detecting small aneurysms and those near the bone. The virtual reality stereoscopic vision obtained through the system was found as a useful tool in intracranial aneurysm diagnosis and pre-operative 3D imaging. Copyright © 2018 Elsevier B.V. All rights reserved.

Virtual planning in orthognathic surgery.

PubMed

Stokbro, K; Aagaard, E; Torkov, P; Bell, R B; Thygesen, T

2014-08-01

Numerous publications regarding virtual surgical planning protocols have been published, most reporting only one or two case reports to emphasize the hands-on planning. None have systematically reviewed the data published from clinical trials. This systematic review analyzes the precision and accuracy of three-dimensional (3D) virtual surgical planning of orthognathic procedures compared with the actual surgical outcome following orthognathic surgery reported in clinical trials. A systematic search of the current literature was conducted to identify clinical trials with a sample size of more than five patients, comparing the virtual surgical plan with the actual surgical outcome. Search terms revealed a total of 428 titles, out of which only seven articles were included, with a combined sample size of 149 patients. Data were presented in three different ways: intra-class correlation coefficient, 3D surface area with a difference <2mm, and linear and angular differences in three dimensions. Success criteria were set at 2mm mean difference in six articles; 125 of the 133 patients included in these articles were regarded as having had a successful outcome. Due to differences in the presentation of data, meta-analysis was not possible. Virtual planning appears to be an accurate and reproducible method for orthognathic treatment planning. A more uniform presentation of the data is necessary to allow the performance of a meta-analysis. Currently, the software system most often used for 3D virtual planning in clinical trials is SimPlant (Materialise). More independent clinical trials are needed to further validate the precision of virtual planning. Copyright © 2014 International Association of Oral and Maxillofacial Surgeons. All rights reserved.

Translation of First North American 50 and 70 cc Total Artificial Heart Virtual and Clinical Implantations: Utility of 3D Computed Tomography to Test Fit Devices.

PubMed

Ferng, Alice S; Oliva, Isabel; Jokerst, Clinton; Avery, Ryan; Connell, Alana M; Tran, Phat L; Smith, Richard G; Khalpey, Zain

2017-08-01

Since the creation of SynCardia's 50 cc Total Artificial Hearts (TAHs), patients with irreversible biventricular failure now have two sizing options. Herein, a case series of three patients who have undergone successful 50 and 70 cc TAH implantation with complete closure of the chest cavity utilizing preoperative "virtual implantation" of different sized devices for surgical planning are presented. Computed tomography (CT) images were used for preoperative planning prior to TAH implantation. Three-dimensional (3D) reconstructions of preoperative chest CT images were generated and both 50 and 70 cc TAHs were virtually implanted into patients' thoracic cavities. During the simulation, the TAHs were projected over the native hearts in a similar position to the actual implantation, and the relationship between the devices and the atria, ventricles, chest wall, and diaphragm were assessed. The 3D reconstructed images and virtual modeling were used to simulate and determine for each patient if the 50 or 70 cc TAH would have a higher likelihood of successful implantation without complications. Subsequently, all three patients received clinical implants of the properly sized TAH based on virtual modeling, and their chest cavities were fully closed. This virtual implantation increases our confidence that the selected TAH will better fit within the thoracic cavity allowing for improved surgical outcome. Clinical implantation of the TAHs showed that our virtual modeling was an effective method for determining the correct fit and sizing of 50 and 70 cc TAHs. © 2016 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Biological Visualization, Imaging and Simulation(Bio-VIS) at NASA Ames Research Center: Developing New Software and Technology for Astronaut Training and Biology Research in Space

NASA Technical Reports Server (NTRS)

Smith, Jeffrey

2003-01-01

The Bio- Visualization, Imaging and Simulation (BioVIS) Technology Center at NASA's Ames Research Center is dedicated to developing and applying advanced visualization, computation and simulation technologies to support NASA Space Life Sciences research and the objectives of the Fundamental Biology Program. Research ranges from high resolution 3D cell imaging and structure analysis, virtual environment simulation of fine sensory-motor tasks, computational neuroscience and biophysics to biomedical/clinical applications. Computer simulation research focuses on the development of advanced computational tools for astronaut training and education. Virtual Reality (VR) and Virtual Environment (VE) simulation systems have become important training tools in many fields from flight simulation to, more recently, surgical simulation. The type and quality of training provided by these computer-based tools ranges widely, but the value of real-time VE computer simulation as a method of preparing individuals for real-world tasks is well established. Astronauts routinely use VE systems for various training tasks, including Space Shuttle landings, robot arm manipulations and extravehicular activities (space walks). Currently, there are no VE systems to train astronauts for basic and applied research experiments which are an important part of many missions. The Virtual Glovebox (VGX) is a prototype VE system for real-time physically-based simulation of the Life Sciences Glovebox where astronauts will perform many complex tasks supporting research experiments aboard the International Space Station. The VGX consists of a physical display system utilizing duel LCD projectors and circular polarization to produce a desktop-sized 3D virtual workspace. Physically-based modeling tools (Arachi Inc.) provide real-time collision detection, rigid body dynamics, physical properties and force-based controls for objects. The human-computer interface consists of two magnetic tracking devices (Ascention Inc.) attached to instrumented gloves (Immersion Inc.) which co-locate the user's hands with hand/forearm representations in the virtual workspace. Force-feedback is possible in a work volume defined by a Phantom Desktop device (SensAble inc.). Graphics are written in OpenGL. The system runs on a 2.2 GHz Pentium 4 PC. The prototype VGX provides astronauts and support personnel with a real-time physically-based VE system to simulate basic research tasks both on Earth and in the microgravity of Space. The immersive virtual environment of the VGX also makes it a useful tool for virtual engineering applications including CAD development, procedure design and simulation of human-system systems in a desktop-sized work volume.

Benzene-1,3-dicarboxylic acid 2,5-dimethylpyrrole derivatives as multiple inhibitors of bacterial Mur ligases (MurC-MurF).

PubMed

Perdih, Andrej; Hrast, Martina; Barreteau, Hélène; Gobec, Stanislav; Wolber, Gerhard; Solmajer, Tom

2014-08-01

Enzymes catalyzing the biosynthesis of bacterial peptidoglycan represent traditionally a collection of highly selective targets for novel antibacterial drug design. Four members of the bacterial Mur ligase family-MurC, MurD, MurE and MurF-are involved in the intracellular steps of peptidoglycan biosynthesis, catalyzing the synthesis of the peptide moiety of the Park's nucleotide. In our previous virtual screening campaign, a chemical class of benzene-1,3-dicarboxylic acid 2,5-dimethylpyrrole derivatives exhibiting dual MurD/MurE inhibition properties was discovered. In the present study we further investigated this class of compounds by performing inhibition assays on all four Mur ligases (MurC-MurF). Furthermore, molecular dynamics (MD) simulation studies of one of the initially discovered compound 1 were performed to explore its geometry as well as its energetic behavior based on the Linear Interaction Energy (LIE) method. Further in silico virtual screening (VS) experiments based on the parent active compound 1 were conducted to optimize the discovered series. Selected hits were assayed against all Escherichia coli MurC-MurF enzymes in biochemical inhibition assays and molecules 10-14 containing benzene-1,3-dicarboxylic acid 2,5-dimethylpyrrole coupled with five member-ring rhodanine moiety were found to be multiple inhibitors of the whole MurC-MurF cascade of bacterial enzymes in the micromolar range. Steady-state kinetics studies suggested this class to act as competitive inhibitors of the MurD enzyme towards d-Glu. These compounds represent novel valuable starting point in the development of novel antibacterial agents. Copyright © 2014 Elsevier Ltd. All rights reserved.

Full State Feedback Control for Virtual Power Plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, Jay Tillay

This report presents an object-oriented implementation of full state feedback control for virtual power plants (VPP). The components of the VPP full state feedback control are (1) objectoriented high-fidelity modeling for all devices in the VPP; (2) Distribution System Distributed Quasi-Dynamic State Estimation (DS-DQSE) that enables full observability of the VPP by augmenting actual measurements with virtual, derived and pseudo measurements and performing the Quasi-Dynamic State Estimation (QSE) in a distributed manner, and (3) automated formulation of the Optimal Power Flow (OPF) in real time using the output of the DS-DQSE, and solving the distributed OPF to provide the optimalmore » control commands to the DERs of the VPP.« less

Measurable realistic image-based 3D mapping

NASA Astrophysics Data System (ADS)

Liu, W.; Wang, J.; Wang, J. J.; Ding, W.; Almagbile, A.

2011-12-01

Maps with 3D visual models are becoming a remarkable feature of 3D map services. High-resolution image data is obtained for the construction of 3D visualized models.The3D map not only provides the capabilities of 3D measurements and knowledge mining, but also provides the virtual experienceof places of interest, such as demonstrated in the Google Earth. Applications of 3D maps are expanding into the areas of architecture, property management, and urban environment monitoring. However, the reconstruction of high quality 3D models is time consuming, and requires robust hardware and powerful software to handle the enormous amount of data. This is especially for automatic implementation of 3D models and the representation of complicated surfacesthat still need improvements with in the visualisation techniques. The shortcoming of 3D model-based maps is the limitation of detailed coverage since a user can only view and measure objects that are already modelled in the virtual environment. This paper proposes and demonstrates a 3D map concept that is realistic and image-based, that enables geometric measurements and geo-location services. Additionally, image-based 3D maps provide more detailed information of the real world than 3D model-based maps. The image-based 3D maps use geo-referenced stereo images or panoramic images. The geometric relationships between objects in the images can be resolved from the geometric model of stereo images. The panoramic function makes 3D maps more interactive with users but also creates an interesting immersive circumstance. Actually, unmeasurable image-based 3D maps already exist, such as Google street view, but only provide virtual experiences in terms of photos. The topographic and terrain attributes, such as shapes and heights though are omitted. This paper also discusses the potential for using a low cost land Mobile Mapping System (MMS) to implement realistic image 3D mapping, and evaluates the positioning accuracy that a measureable realistic image-based (MRI) system can produce. The major contribution here is the implementation of measurable images on 3D maps to obtain various measurements from real scenes.

MRI for transformation of preserved organs and their pathologies into digital formats for medical education and creation of a virtual pathology museum. A pilot study.

PubMed

Venkatesh, S K; Wang, G; Seet, J E; Teo, L L S; Chong, V F H

2013-03-01

To evaluate the feasibility of magnetic resonance imaging (MRI) for the transformation of preserved organs and their disease entities into digital formats for medical education and creation of a virtual museum. MRI of selected 114 pathology specimen jars representing different organs and their diseases was performed using a 3 T MRI machine with two or more MRI sequences including three-dimensional (3D) T1-weighted (T1W), 3D-T2W, 3D-FLAIR (fluid attenuated inversion recovery), fat-water separation (DIXON), and gradient-recalled echo (GRE) sequences. Qualitative assessment of MRI for depiction of disease and internal anatomy was performed. Volume rendering was performed on commercially available workstations. The digital images, 3D models, and photographs of specimens were archived into a workstation serving as a virtual pathology museum. MRI was successfully performed on all specimens. The 3D-T1W and 3D-T2W sequences demonstrated the best contrast between normal and pathological tissues. The digital material is a useful aid for understanding disease by giving insights into internal structural changes not apparent on visual inspection alone. Volume rendering produced vivid 3D models with better contrast between normal tissue and diseased tissue compared to real specimens or their photographs in some cases. The digital library provides good illustration material for radiological-pathological correlation by enhancing pathological anatomy and information on nature and signal characteristics of tissues. In some specimens, the MRI appearance may be different from corresponding organ and disease in vivo due to dead tissue and changes induced by prolonged contact with preservative fluid. MRI of pathology specimens is feasible and provides excellent images for education and creating a virtual pathology museum that can serve as permanent record of digital material for self-directed learning, improving teaching aids, and radiological-pathological correlation. Copyright © 2012 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

The Engelbourg's ruins: from 3D TLS point cloud acquisition to 3D virtual and historic models

NASA Astrophysics Data System (ADS)

Koehl, Mathieu; Berger, Solveig; Nobile, Sylvain

2014-05-01

The Castle of Engelbourg was built at the beginning of the 13th century, at the top of the Schlossberg. It is situated on the territory of the municipality of Thann (France), at the crossroads of Alsace and Lorraine, and dominates the outlet of the valley of Thur. Its strategic position was one of the causes of its systematic destructions during the 17th century, and Louis XIV finished his fate by ordering his demolition in 1673. Today only few vestiges remain, of which a section of the main tower from about 7m of diameter and 4m of wide laying on its slice, unique characteristic in the regional castral landscape. It is visible since the valley, was named "the Eye of the witch", and became a key attraction of the region. The site, which extends over approximately one hectare, is for several years the object of numerous archaeological studies and is at the heart of a project of valuation of the vestiges today. It was indeed a key objective, among the numerous planned works, to realize a 3D model of the site in its current state, in other words, a virtual model "such as seized", exploitable as well from a cultural and tourist point of view as by scientists and in archaeological researches. The team of the ICube/INSA lab had in responsibility the realization of this model, the acquisition of the data until the delivery of the virtual model, thanks to 3D TLS and topographic surveying methods. It was also planned to integrate into this 3D model, data of 2D archives, stemming from series of former excavations. The objectives of this project were the following ones: • Acquisition of 3D digital data of the site and 3D modelling • Digitization of the 2D archaeological data and integration in the 3D model • Implementation of a database connected to the 3D model • Virtual Visit of the site The obtained results allowed us to visualize every 3D object individually, under several forms (point clouds, 3D meshed objects and models, etc.) and at several levels of detail. The 3D model integrated into a GIS is now a precious means of communication for the valuation of the site. Accessible to all, including to the distant people, he allows discover the castle and his history in an educational and relevant way. From an archaeological point of view, the 3D model brings an overall view and a backward movement on the constitution of the site, which a 2D document cannot easily offer. The 3D navigation and the integration of 2D data in the model allow analyze vestiges in another way, contributing to the faster establishment of new hypotheses. Complementary to other methods already exploited in archaeology, the analysis by the 3D vision is, for the scientists, a significant saving of time which they can so dedicate to the more thorough study of certain put aside hypotheses. In parallel, we created several panoramas, and set up a virtual and interactive visit of the site. In the optics to perpetuate this project, and to offer to the future users the ways to continue and to update this study, we tested and set up the methodologies of processing. We were so able to release procedures clear, orderly and applicable as well to the case of Engelbourg as to other similar studies. At least, some hypotheses permits to reconstruct virtually first versions of the original state of the castle.

Virtual reality in the treatment of persecutory delusions: randomised controlled experimental study testing how to reduce delusional conviction.

PubMed

Freeman, Daniel; Bradley, Jonathan; Antley, Angus; Bourke, Emilie; DeWeever, Natalie; Evans, Nicole; Černis, Emma; Sheaves, Bryony; Waite, Felicity; Dunn, Graham; Slater, Mel; Clark, David M

2016-07-01

Persecutory delusions may be unfounded threat beliefs maintained by safety-seeking behaviours that prevent disconfirmatory evidence being successfully processed. Use of virtual reality could facilitate new learning. To test the hypothesis that enabling patients to test the threat predictions of persecutory delusions in virtual reality social environments with the dropping of safety-seeking behaviours (virtual reality cognitive therapy) would lead to greater delusion reduction than exposure alone (virtual reality exposure). Conviction in delusions and distress in a real-world situation were assessed in 30 patients with persecutory delusions. Patients were then randomised to virtual reality cognitive therapy or virtual reality exposure, both with 30 min in graded virtual reality social environments. Delusion conviction and real-world distress were then reassessed. In comparison with exposure, virtual reality cognitive therapy led to large reductions in delusional conviction (reduction 22.0%, P = 0.024, Cohen's d = 1.3) and real-world distress (reduction 19.6%, P = 0.020, Cohen's d = 0.8). Cognitive therapy using virtual reality could prove highly effective in treating delusions. © The Royal College of Psychiatrists 2016.

Virtual reality in the treatment of persecutory delusions: randomised controlled experimental study testing how to reduce delusional conviction

PubMed Central

Freeman, Daniel; Bradley, Jonathan; Antley, Angus; Bourke, Emilie; DeWeever, Natalie; Evans, Nicole; Černis, Emma; Sheaves, Bryony; Waite, Felicity; Dunn, Graham; Slater, Mel; Clark, David M.

2016-01-01

Background Persecutory delusions may be unfounded threat beliefs maintained by safety-seeking behaviours that prevent disconfirmatory evidence being successfully processed. Use of virtual reality could facilitate new learning. Aims To test the hypothesis that enabling patients to test the threat predictions of persecutory delusions in virtual reality social environments with the dropping of safety-seeking behaviours (virtual reality cognitive therapy) would lead to greater delusion reduction than exposure alone (virtual reality exposure). Method Conviction in delusions and distress in a real-world situation were assessed in 30 patients with persecutory delusions. Patients were then randomised to virtual reality cognitive therapy or virtual reality exposure, both with 30 min in graded virtual reality social environments. Delusion conviction and real-world distress were then reassessed. Results In comparison with exposure, virtual reality cognitive therapy led to large reductions in delusional conviction (reduction 22.0%, P = 0.024, Cohen's d = 1.3) and real-world distress (reduction 19.6%, P = 0.020, Cohen's d = 0.8). Conclusion Cognitive therapy using virtual reality could prove highly effective in treating delusions. PMID:27151071

Options in virtual 3D, optical-impression-based planning of dental implants.

PubMed

Reich, Sven; Kern, Thomas; Ritter, Lutz

2014-01-01

If a 3D radiograph, which in today's dentistry often consists of a CBCT dataset, is available for computerized implant planning, the 3D planning should also consider functional prosthetic aspects. In a conventional workflow, the CBCT is done with a specially produced radiopaque prosthetic setup that makes the desired prosthetic situation visible during virtual implant planning. If an exclusively digital workflow is chosen, intraoral digital impressions are taken. On these digital models, the desired prosthetic suprastructures are designed. The entire datasets are virtually superimposed by a "registration" process on the corresponding structures (teeth) in the CBCTs. Thus, both the osseous and prosthetic structures are visible in one single 3D application and make it possible to consider surgical and prosthetic aspects. After having determined the implant positions on the computer screen, a drilling template is designed digitally. According to this design (CAD), a template is printed or milled in CAM process. This template is the first physically extant product in the entire workflow. The article discusses the options and limitations of this workflow.

A New Approach to Improve Cognition, Muscle Strength, and Postural Balance in Community-Dwelling Elderly with a 3-D Virtual Reality Kayak Program.

PubMed

Park, Junhyuck; Yim, JongEun

2016-01-01

Aging is usually accompanied with deterioration of physical abilities, such as muscular strength, sensory sensitivity, and functional capacity. Recently, intervention methods with virtual reality have been introduced, providing an enjoyable therapy for elderly. The aim of this study was to investigate whether a 3-D virtual reality kayak program could improve the cognitive function, muscle strength, and balance of community-dwelling elderly. Importantly, kayaking involves most of the upper body musculature and needs the balance control. Seventy-two participants were randomly allocated into the kayak program group (n = 36) and the control group (n = 36). The two groups were well matched with respect to general characteristics at baseline. The participants in both groups performed a conventional exercise program for 30 min, and then the 3-D virtual reality kayak program was performed in the kayak program group for 20 min, two times a week for 6 weeks. Cognitive function was measured using the Montreal Cognitive Assessment. Muscle strength was measured using the arm curl and handgrip strength tests. Standing and sitting balance was measured using the Good Balance system. The post-test was performed in the same manner as the pre-test; the overall outcomes such as cognitive function (p < 0.05), muscle strength (p < 0.05), and balance (standing and sitting balance, p < 0.05) were significantly improved in kayak program group compared to the control group. We propose that the 3-D virtual reality kayak program is a promising intervention method for improving the cognitive function, muscle strength, and balance of elderly.

Application of Shape Similarity in Pose Selection and Virtual Screening in CSARdock2014 Exercise.

PubMed

Kumar, Ashutosh; Zhang, Kam Y J

2016-06-27

To evaluate the applicability of shape similarity in docking-based pose selection and virtual screening, we participated in the CSARdock2014 benchmark exercise for identifying the correct docking pose of inhibitors targeting factor XA, spleen tyrosine kinase, and tRNA methyltransferase. This exercise provides a valuable opportunity for researchers to test their docking programs, methods, and protocols in a blind testing environment. In the CSARdock2014 benchmark exercise, we have implemented an approach that uses ligand 3D shape similarity to facilitate docking-based pose selection and virtual screening. We showed here that ligand 3D shape similarity between bound poses could be used to identify the native-like pose from an ensemble of docking-generated poses. Our method correctly identified the native pose as the top-ranking pose for 73% of test cases in a blind testing environment. Moreover, the pose selection results also revealed an excellent correlation between ligand 3D shape similarity scores and RMSD to X-ray crystal structure ligand. In the virtual screening exercise, the average RMSD for our pose prediction was found to be 1.02 Å, and it was one of the top performances achieved in CSARdock2014 benchmark exercise. Furthermore, the inclusion of shape similarity improved virtual screening performance of docking-based scoring and ranking. The coefficient of determination (r(2)) between experimental activities and docking scores for 276 spleen tyrosine kinase inhibitors was found to be 0.365 but reached 0.614 when the ligand 3D shape similarity was included.

EFL Learner Collaborative Interaction in Second Life

ERIC Educational Resources Information Center

Peterson, Mark

2012-01-01

This paper reports on the task-based interaction of English as a Foreign Language (EFL) learners in the 3D multiuser virtual environment (MUVE) Second Life. The discussion first explores research on the precursors of MUVEs, text-based 2D virtual worlds known as MOOs. This is followed by an examination of studies on the use of MUVEs in Computer…

Augmented Reality versus Virtual Reality for 3D Object Manipulation.

PubMed

Krichenbauer, Max; Yamamoto, Goshiro; Taketom, Takafumi; Sandor, Christian; Kato, Hirokazu

2018-02-01

Virtual Reality (VR) Head-Mounted Displays (HMDs) are on the verge of becoming commodity hardware available to the average user and feasible to use as a tool for 3D work. Some HMDs include front-facing cameras, enabling Augmented Reality (AR) functionality. Apart from avoiding collisions with the environment, interaction with virtual objects may also be affected by seeing the real environment. However, whether these effects are positive or negative has not yet been studied extensively. For most tasks it is unknown whether AR has any advantage over VR. In this work we present the results of a user study in which we compared user performance measured in task completion time on a 9 degrees of freedom object selection and transformation task performed either in AR or VR, both with a 3D input device and a mouse. Our results show faster task completion time in AR over VR. When using a 3D input device, a purely VR environment increased task completion time by 22.5 percent on average compared to AR ( ). Surprisingly, a similar effect occurred when using a mouse: users were about 17.3 percent slower in VR than in AR ( ). Mouse and 3D input device produced similar task completion times in each condition (AR or VR) respectively. We further found no differences in reported comfort.

Assessing the Regioselectivity of OleD-Catalyzed Glycosylation with a Diverse Set of Acceptors

PubMed Central

Zhou, Maoquan; Hamza, Adel; Zhan, Chang-Guo; Thorson, Jon S.

2013-01-01

To explore the acceptor regioselectivity of OleD-catalyzed glucosylation, the products of OleD-catalyzed reactions with the six structurally diverse acceptors - flavones (daidzein), isoflavones (flavopiridol), stilbenes (resveratrol), indole alkaloids (10-hydroxycamptothecin), and steroids (2-methoxyestradiol) - were determined. This study highlights the first synthesis of flavopiridol and 2-methoxyestradiol glucosides and confirms the ability of OleD to glucosylate both aromatic and aliphatic nucleophiles. In all cases, molecular dynamics simulations were consistent with the determined product distribution and suggest the potential to develop a virtual screening model to identify additional OleD substrates. PMID:23360118

An efficient hole-filling method based on depth map in 3D view generation

NASA Astrophysics Data System (ADS)

Liang, Haitao; Su, Xiu; Liu, Yilin; Xu, Huaiyuan; Wang, Yi; Chen, Xiaodong

2018-01-01

New virtual view is synthesized through depth image based rendering(DIBR) using a single color image and its associated depth map in 3D view generation. Holes are unavoidably generated in the 2D to 3D conversion process. We propose a hole-filling method based on depth map to address the problem. Firstly, we improve the process of DIBR by proposing a one-to-four (OTF) algorithm. The "z-buffer" algorithm is used to solve overlap problem. Then, based on the classical patch-based algorithm of Criminisi et al., we propose a hole-filling algorithm using the information of depth map to handle the image after DIBR. In order to improve the accuracy of the virtual image, inpainting starts from the background side. In the calculation of the priority, in addition to the confidence term and the data term, we add the depth term. In the search for the most similar patch in the source region, we define the depth similarity to improve the accuracy of searching. Experimental results show that the proposed method can effectively improve the quality of the 3D virtual view subjectively and objectively.

Printed three-dimensional anatomic templates for virtual preoperative planning before reconstruction of old pelvic injuries: initial results.

PubMed

Wu, Xin-Bao; Wang, Jun-Qiang; Zhao, Chun-Peng; Sun, Xu; Shi, Yin; Zhang, Zi-An; Li, Yu-Neng; Wang, Man-Yi

2015-02-20

Old pelvis fractures are among the most challenging fractures to treat because of their complex anatomy, difficult-to-access surgical sites, and the relatively low incidence of such cases. Proper evaluation and surgical planning are necessary to achieve the pelvic ring symmetry and stable fixation of the fracture. The goal of this study was to assess the use of three-dimensional (3D) printing techniques for surgical management of old pelvic fractures. First, 16 dried human cadaveric pelvises were used to confirm the anatomical accuracy of the 3D models printed based on radiographic data. Next, nine clinical cases between January 2009 and April 2013 were used to evaluate the surgical reconstruction based on the 3D printed models. The pelvic injuries were all type C, and the average time from injury to reconstruction was 11 weeks (range: 8-17 weeks). The workflow consisted of: (1) Printing patient-specific bone models based on preoperative computed tomography (CT) scans, (2) virtual fracture reduction using the printed 3D anatomic template, (3) virtual fracture fixation using Kirschner wires, and (4) preoperatively measuring the osteotomy and implant position relative to landmarks using the virtually defined deformation. These models aided communication between surgical team members during the procedure. This technique was validated by comparing the preoperative planning to the intraoperative procedure. The accuracy of the 3D printed models was within specification. Production of a model from standard CT DICOM data took 7 hours (range: 6-9 hours). Preoperative planning using the 3D printed models was feasible in all cases. Good correlation was found between the preoperative planning and postoperative follow-up X-ray in all nine cases. The patients were followed for 3-29 months (median: 5 months). The fracture healing time was 9-17 weeks (mean: 10 weeks). No delayed incision healing, wound infection, or nonunions occurred. The results were excellent in two cases, good in five, and poor in two based on the Majeed score. The 3D printing planning technique for pelvic surgery was successfully integrated into a clinical workflow to improve patient-specific preoperative planning by providing a visual and haptic model of the injury and allowing patient-specific adaptation of each osteosynthesis implant to the virtually reduced pelvis.

Intra-operative 3D imaging system for robot-assisted fracture manipulation.

PubMed

Dagnino, G; Georgilas, I; Tarassoli, P; Atkins, R; Dogramadzi, S

2015-01-01

Reduction is a crucial step in the treatment of broken bones. Achieving precise anatomical alignment of bone fragments is essential for a good fast healing process. Percutaneous techniques are associated with faster recovery time and lower infection risk. However, deducing intra-operatively the desired reduction position is quite challenging due to the currently available technology. The 2D nature of this technology (i.e. the image intensifier) doesn't provide enough information to the surgeon regarding the fracture alignment and rotation, which is actually a three-dimensional problem. This paper describes the design and development of a 3D imaging system for the intra-operative virtual reduction of joint fractures. The proposed imaging system is able to receive and segment CT scan data of the fracture, to generate the 3D models of the bone fragments, and display them on a GUI. A commercial optical tracker was included into the system to track the actual pose of the bone fragments in the physical space, and generate the corresponding pose relations in the virtual environment of the imaging system. The surgeon virtually reduces the fracture in the 3D virtual environment, and a robotic manipulator connected to the fracture through an orthopedic pin executes the physical reductions accordingly. The system is here evaluated through fracture reduction experiments, demonstrating a reduction accuracy of 1.04 ± 0.69 mm (translational RMSE) and 0.89 ± 0.71 ° (rotational RMSE).

A Fixed-Wing Aircraft Simulation Tool for Improving the efficiency of DoD Acquisition

DTIC Science & Technology

2015-10-05

simulation tool , CREATETM-AV Helios [12-14], a high fidelity rotary wing vehicle simulation tool , and CREATETM-AV DaVinci [15-16], a conceptual through...05/2015 Oct 2008-Sep 2015 A Fixed-Wing Aircraft Simulation Tool for Improving the Efficiency of DoD Acquisition Scott A. Morton and David R...multi-disciplinary fixed-wing virtual aircraft simulation tool incorporating aerodynamics, structural dynamics, kinematics, and kinetics. Kestrel allows

Enhanced LOD Concepts for Virtual 3d City Models

NASA Astrophysics Data System (ADS)

Benner, J.; Geiger, A.; Gröger, G.; Häfele, K.-H.; Löwner, M.-O.

2013-09-01

Virtual 3D city models contain digital three dimensional representations of city objects like buildings, streets or technical infrastructure. Because size and complexity of these models continuously grow, a Level of Detail (LoD) concept effectively supporting the partitioning of a complete model into alternative models of different complexity and providing metadata, addressing informational content, complexity and quality of each alternative model is indispensable. After a short overview on various LoD concepts, this paper discusses the existing LoD concept of the CityGML standard for 3D city models and identifies a number of deficits. Based on this analysis, an alternative concept is developed and illustrated with several examples. It differentiates between first, a Geometric Level of Detail (GLoD) and a Semantic Level of Detail (SLoD), and second between the interior building and its exterior shell. Finally, a possible implementation of the new concept is demonstrated by means of an UML model.

Quasi-Facial Communication for Online Learning Using 3D Modeling Techniques

ERIC Educational Resources Information Center

Wang, Yushun; Zhuang, Yueting

2008-01-01

Online interaction with 3D facial animation is an alternative way of face-to-face communication for distance education. 3D facial modeling is essential for virtual educational environments establishment. This article presents a novel 3D facial modeling solution that facilitates quasi-facial communication for online learning. Our algorithm builds…

An integrated 3D log processing optimization system for small sawmills in central Appalachia

Treesearch

Wenshu Lin; Jingxin Wang

2013-01-01

An integrated 3D log processing optimization system was developed to perform 3D log generation, opening face determination, headrig log sawing simulation, fl itch edging and trimming simulation, cant resawing, and lumber grading. A circular cross-section model, together with 3D modeling techniques, was used to reconstruct 3D virtual logs. Internal log defects (knots)...

University of Kentucky

Science.gov Websites

community are writing new chapters. Follow Along Take the Virtual Tour An immersive, 3D tour of our Dining Net Price Calculator Visit Virtual Visit From President Capilouto Right now, you are joining

Recent advances in head-mounted light field displays for virtual and augmented reality (Conference Presentation)

NASA Astrophysics Data System (ADS)

Hua, Hong

2017-02-01

Head-mounted light field displays render a true 3D scene by sampling either the projections of the 3D scene at different depths or the directions of the light rays apparently emitted by the 3D scene and viewed from different eye positions. They are capable of rendering correct or nearly correct focus cues and addressing the very well-known vergence-accommodation mismatch problem in conventional virtual and augmented reality displays. In this talk, I will focus on reviewing recent advancements of head-mounted light field displays for VR and AR applications. I will demonstrate examples of HMD systems developed in my group.

Accuracy of virtual surgical planning in two-jaw orthognathic surgery: comparison of planned and actual results.

PubMed

Zhang, Nan; Liu, Shuguang; Hu, Zhiai; Hu, Jing; Zhu, Songsong; Li, Yunfeng

2016-08-01

This study aims to evaluate the accuracy of virtual surgical planning in two-jaw orthognathic surgery via quantitative comparison of preoperative planned and postoperative actual skull models. Thirty consecutive patients who required two-jaw orthognathic surgery were included. A composite skull model was reconstructed by using Digital Imaging and Communications in Medicine (DICOM) data from spiral computed tomography (CT) and STL (stereolithography) data from surface scanning of the dental arch. LeFort I osteotomy of the maxilla and bilateral sagittal split ramus osteotomy (of the mandible were simulated by using Dolphin Imaging 11.7 Premium (Dolphin Imaging and Management Solutions, Chatsworth, CA). Genioplasty was performed, if indicated. The virtual plan was then transferred to the operation room by using three-dimensional (3-D)-printed surgical templates. Linear and angular differences between virtually simulated and postoperative skull models were evaluated. The virtual surgical planning was successfully transferred to actual surgery with the help of 3-D-printed surgical templates. All patients were satisfied with the postoperative facial profile and occlusion. The overall mean linear difference was 0.81 mm (0.71 mm for the maxilla and 0.91 mm for the mandible); and the overall mean angular difference was 0.95 degrees. Virtual surgical planning and 3-D-printed surgical templates facilitated the diagnosis, treatment planning, and accurate repositioning of bony segments in two-jaw orthognathic surgery. Copyright © 2016 Elsevier Inc. All rights reserved.

Augmented Virtuality: A Real-time Process for Presenting Real-world Visual Sensory Information in an Immersive Virtual Environment for Planetary Exploration

NASA Astrophysics Data System (ADS)

McFadden, D.; Tavakkoli, A.; Regenbrecht, J.; Wilson, B.

2017-12-01

Virtual Reality (VR) and Augmented Reality (AR) applications have recently seen an impressive growth, thanks to the advent of commercial Head Mounted Displays (HMDs). This new visualization era has opened the possibility of presenting researchers from multiple disciplines with data visualization techniques not possible via traditional 2D screens. In a purely VR environment researchers are presented with the visual data in a virtual environment, whereas in a purely AR application, a piece of virtual object is projected into the real world with which researchers could interact. There are several limitations to the purely VR or AR application when taken within the context of remote planetary exploration. For example, in a purely VR environment, contents of the planet surface (e.g. rocks, terrain, or other features) should be created off-line from a multitude of images using image processing techniques to generate 3D mesh data that will populate the virtual surface of the planet. This process usually takes a tremendous amount of computational resources and cannot be delivered in real-time. As an alternative, video frames may be superimposed on the virtual environment to save processing time. However, such rendered video frames will lack 3D visual information -i.e. depth information. In this paper, we present a technique to utilize a remotely situated robot's stereoscopic cameras to provide a live visual feed from the real world into the virtual environment in which planetary scientists are immersed. Moreover, the proposed technique will blend the virtual environment with the real world in such a way as to preserve both the depth and visual information from the real world while allowing for the sensation of immersion when the entire sequence is viewed via an HMD such as Oculus Rift. The figure shows the virtual environment with an overlay of the real-world stereoscopic video being presented in real-time into the virtual environment. Notice the preservation of the object's shape, shadows, and depth information. The distortions shown in the image are due to the rendering of the stereoscopic data into a 2D image for the purposes of taking screenshots.

Active Learning through the Use of Virtual Environments

ERIC Educational Resources Information Center

Mayrose, James

2012-01-01

Immersive Virtual Reality (VR) has seen explosive growth over the last decade. Immersive VR attempts to give users the sensation of being fully immersed in a synthetic environment by providing them with 3D hardware, and allowing them to interact with objects in virtual worlds. The technology is extremely effective for learning and exploration, and…

The Potential for Scientific Collaboration in Virtual Ecosystems

ERIC Educational Resources Information Center

Magerko, Brian

2010-01-01

This article explores the potential benefits of creating "virtual ecosystems" from real-world data. These ecosystems are intended to be realistic virtual representations of environments that may be costly or difficult to access in person. They can be constructed as 3D worlds rendered from stereo video data, augmented with scientific data, and then…

Innovation Education Enabled through a Collaborative Virtual Reality Learning Environment

ERIC Educational Resources Information Center

Thorsteinsson, Gisli; Page, Tom; Lehtonen, Miika; Ha, Joong Gyu

2006-01-01

This article provides a descriptive account of the development of an approach to the support of design and technology education with 3D Virtual Reality (VR) technologies on an open and distance learning basis. This work promotes an understanding of the implications and possibilities of advanced virtual learning technologies in education for…

Managing Multimodal Data in Virtual World Research for Language Learning

ERIC Educational Resources Information Center

Palomeque, Cristina; Pujolà, Joan-Tomàs

2018-01-01

The study of multimodality in communication has attracted the attention of researchers studying online multimodal environments such as virtual worlds. Specifically, 3D virtual worlds have especially attracted the interest of educators and academics due to the multiplicity of verbal channels, which are often comprised of text and voice channels, as…