Science.gov

Sample records for 3d virtual models

  1. 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

  2. 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

  3. 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…

  4. 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 modelVirtual 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

  5. 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

  6. Combination of Virtual Tours, 3d Model and Digital Data in a 3d Archaeological Knowledge and Information System

    NASA Astrophysics Data System (ADS)

    Koehl, M.; Brigand, N.

    2012-08-01

    The site of the Engelbourg ruined castle in Thann, Alsace, France, has been for some years the object of all the attention of the city, which is the owner, and also of partners like historians and archaeologists who are in charge of its study. The valuation of the site is one of the main objective, as well as its conservation and its knowledge. The aim of this project is to use the environment of the virtual tour viewer as new base for an Archaeological Knowledge and Information System (AKIS). With available development tools we add functionalities in particular through diverse scripts that convert the viewer into a real 3D interface. By beginning with a first virtual tour that contains about fifteen panoramic images, the site of about 150 times 150 meters can be completely documented by offering the user a real interactivity and that makes visualization very concrete, almost lively. After the choice of pertinent points of view, panoramic images were realized. For the documentation, other sets of images were acquired at various seasons and climate conditions, which allow documenting the site in different environments and states of vegetation. The final virtual tour was deducted from them. The initial 3D model of the castle, which is virtual too, was also joined in the form of panoramic images for completing the understanding of the site. A variety of types of hotspots were used to connect the whole digital documentation to the site, including videos (as reports during the acquisition phases, during the restoration works, during the excavations, etc.), digital georeferenced documents (archaeological reports on the various constituent elements of the castle, interpretation of the excavations and the searches, description of the sets of collected objects, etc.). The completely personalized interface of the system allows either to switch from a panoramic image to another one, which is the classic case of the virtual tours, or to go from a panoramic photographic image

  7. An improved virtual aberration model to simulate mask 3D and resist effects

    NASA Astrophysics Data System (ADS)

    Kanaya, Reiji; Fujii, Koichi; Imai, Motokatsu; Matsuyama, Tomoyuki; Tsuzuki, Takao; Lin, Qun Ying

    2015-03-01

    As shrinkage of design features progresses, the difference in best focus positions among different patterns is becoming a fatal issue, especially when many patterns co-exist in a layer. The problem arises from three major factors: aberrations of projection optics, mask 3D topography effects, and resist thickness effects. Aberrations in projection optics have already been thoroughly investigated, but mask 3D topography effects and resist thickness effects are still under study. It is well known that mask 3D topography effects can be simulated by various Electro-magnetic Field (EMF) analysis methods. However, it is almost impossible to use them for full chip modeling because all of these methods are extremely computationally intensive. Consequently, they usually apply only to a limited range of mask patterns which are about tens of square micro meters in area. Resist thickness effects on best focus positions are rarely treated as a topic of lithography investigations. Resist 3D effects are treated mostly for resist profile prediction, which also requires an intensive EMF analysis when one needs to predict it accurately. In this paper, we present a simplified Virtual Aberration (VA) model to simulate both mask 3D induced effects and resist thickness effects. A conventional simulator, when applied with this simplified method, can factor in both mask 3D topography effects and resist thickness effects. Thus it can be used to model inter-pattern Best Focus Difference (BFD) issues with the least amount of rigorous EMF analysis.

  8. 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…

  9. 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

  10. 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.

  11. Exploring conformational search protocols for ligand-based virtual screening and 3-D QSAR modeling.

    PubMed

    Cappel, Daniel; Dixon, Steven L; Sherman, Woody; Duan, Jianxin

    2015-02-01

    3-D ligand conformations are required for most ligand-based drug design methods, such as pharmacophore modeling, shape-based screening, and 3-D QSAR model building. Many studies of conformational search methods have focused on the reproduction of crystal structures (i.e. bioactive conformations); however, for ligand-based modeling the key question is how to generate a ligand alignment that produces the best results for a given query molecule. In this work, we study different conformation generation modes of ConfGen and the impact on virtual screening (Shape Screening and e-Pharmacophore) and QSAR predictions (atom-based and field-based). In addition, we develop a new search method, called common scaffold alignment, that automatically detects the maximum common scaffold between each screening molecule and the query to ensure identical coordinates of the common core, thereby minimizing the noise introduced by analogous parts of the molecules. In general, we find that virtual screening results are relatively insensitive to the conformational search protocol; hence, a conformational search method that generates fewer conformations could be considered "better" because it is more computationally efficient for screening. However, for 3-D QSAR modeling we find that more thorough conformational sampling tends to produce better QSAR predictions. In addition, significant improvements in QSAR predictions are obtained with the common scaffold alignment protocol developed in this work, which focuses conformational sampling on parts of the molecules that are not part of the common scaffold. PMID:25408244

  12. A virtual interface for interactions with 3D models of the human body.

    PubMed

    De Paolis, Lucio T; Pulimeno, Marco; Aloisio, Giovanni

    2009-01-01

    The developed system is the first prototype of a virtual interface designed to avoid contact with the computer so that the surgeon is able to visualize 3D models of the patient's organs more effectively during surgical procedure or to use this in the pre-operative planning. The doctor will be able to rotate, to translate and to zoom in on 3D models of the patient's organs simply by moving his finger in free space; in addition, it is possible to choose to visualize all of the organs or only some of them. All of the interactions with the models happen in real-time using the virtual interface which appears as a touch-screen suspended in free space in a position chosen by the user when the application is started up. Finger movements are detected by means of an optical tracking system and are used to simulate touch with the interface and to interact by pressing the buttons present on the virtual screen. PMID:19377116

  13. Building virtual 3D bone fragment models to control diaphyseal fracture reduction

    NASA Astrophysics Data System (ADS)

    Leloup, Thierry; Schuind, Frederic; Lasudry, Nadine; Van Ham, Philippe

    1999-05-01

    Most fractures of the long bones are displaced and need to be surgically reduced. External fixation is often used but the crucial point of this technique is the control of reduction, which is effected with a brilliance amplifier. This system, giving instantly a x-ray image, has many disadvantages. It implies frequent irradiation to the patient and the surgical team, the visual field is limited, the supplied images are distorted and it only gives 2D information. Consequently, the reduction is occasionally imperfect although intraoperatively it appears acceptable. Using the pains inserted in each fragment as markers and an optical tracker, it is possible to build a virtual 3D model for each principal fragment and to follow its movement during the reduction. This system will supply a 3D image of the fracture in real time and without irradiation. The brilliance amplifier could then be replaced by such a virtual reality system to provide the surgeon with an accurate tool facilitating the reduction of the fracture. The purpose of this work is to show how to build the 3D model for each principal bone fragment.

  14. 3D modeling of the Strasbourg's Cathedral basements for interdisciplinary research and virtual visits

    NASA Astrophysics Data System (ADS)

    Landes, T.; Kuhnle, G.; Bruna, R.

    2015-08-01

    On the occasion of the millennium celebration of Strasbourg Cathedral, a transdisciplinary research group composed of archaeologists, surveyors, architects, art historians and a stonemason revised the 1966-1972 excavations under the St. Lawrence's Chapel of the Cathedral having remains of Roman and medieval masonry. The 3D modeling of the Chapel has been realized based on the combination of conventional surveying techniques for the network creation, laser scanning for the model creation and photogrammetric techniques for the texturing of a few parts. According to the requirements and the end-user of the model, the level of detail and level of accuracy have been adapted and assessed for every floor. The basement has been acquired and modeled with more details and a higher accuracy than the other parts. Thanks to this modeling work, archaeologists can confront their assumptions to those of other disciplines by simulating constructions of other worship edifices on the massive stones composing the basement. The virtual reconstructions provided evidence in support of these assumptions and served for communication via virtual visits.

  15. 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…

  16. Novel 3D modeling methods for virtual fabrication and EDA compatible design of MEMS via parametric libraries

    NASA Astrophysics Data System (ADS)

    Schröpfer, Gerold; Lorenz, Gunar; Rouvillois, Stéphane; Breit, Stephen

    2010-06-01

    This paper provides a brief summary of the state-of-the-art of MEMS-specific modeling techniques and describes the validation of new models for a parametric component library. Two recently developed 3D modeling tools are described in more detail. The first one captures a methodology for designing MEMS devices and simulating them together with integrated electronics within a standard electronic design automation (EDA) environment. The MEMS designer can construct the MEMS model directly in a 3D view. The resulting 3D model differs from a typical feature-based 3D CAD modeling tool in that there is an underlying behavioral model and parametric layout associated with each MEMS component. The model of the complete MEMS device that is shared with the standard EDA environment can be fully parameterized with respect to manufacturing- and design-dependent variables. Another recent innovation is a process modeling tool that allows accurate and highly realistic visualization of the step-by-step creation of 3D micro-fabricated devices. The novelty of the tool lies in its use of voxels (3D pixels) rather than conventional 3D CAD techniques to represent the 3D geometry. Case studies for experimental devices are presented showing how the examination of these virtual prototypes can reveal design errors before mask tape out, support process development before actual fabrication and also enable failure analysis after manufacturing.

  17. Virtual Boutique: a 3D modeling and content-based management approach to e-commerce

    NASA Astrophysics Data System (ADS)

    Paquet, Eric; El-Hakim, Sabry F.

    2000-12-01

    The Virtual Boutique is made out of three modules: the decor, the market and the search engine. The decor is the physical space occupied by the Virtual Boutique. It can reproduce any existing boutique. For this purpose, photogrammetry is used. A set of pictures of a real boutique or space is taken and a virtual 3D representation of this space is calculated from them. Calculations are performed with software developed at NRC. This representation consists of meshes and texture maps. The camera used in the acquisition process determines the resolution of the texture maps. Decorative elements are added like painting, computer generated objects and scanned objects. The objects are scanned with laser scanner developed at NRC. This scanner allows simultaneous acquisition of range and color information based on white laser beam triangulation. The second module, the market, is made out of all the merchandises and the manipulators, which are used to manipulate and compare the objects. The third module, the search engine, can search the inventory based on an object shown by the customer in order to retrieve similar objects base don shape and color. The items of interest are displayed in the boutique by reconfiguring the market space, which mean that the boutique can be continuously customized according to the customer's needs. The Virtual Boutique is entirely written in Java 3D and can run in mono and stereo mode and has been optimized in order to allow high quality rendering.

  18. 3D Elevation Program—Virtual USA in 3D

    USGS Publications Warehouse

    Lukas, Vicki; Stoker, J.M.

    2016-01-01

    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.  

  19. 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 combining…

  20. Model-based 3D human shape estimation from silhouettes for virtual fitting

    NASA Astrophysics Data System (ADS)

    Saito, Shunta; Kouchi, Makiko; Mochimaru, Masaaki; Aoki, Yoshimitsu

    2014-03-01

    We propose a model-based 3D human shape reconstruction system from two silhouettes. Firstly, we synthesize a deformable body model from 3D human shape database consists of a hundred whole body mesh models. Each mesh model is homologous, so that it has the same topology and same number of vertices among all models. We perform principal component analysis (PCA) on the database and synthesize an Active Shape Model (ASM). ASM allows changing the body type of the model with a few parameters. The pose changing of our model can be achieved by reconstructing the skeleton structures from implanted joints of the model. By applying pose changing after body type deformation, our model can represents various body types and any pose. We apply the model to the problem of 3D human shape reconstruction from front and side silhouette. Our approach is simply comparing the contours between the model's and input silhouettes', we then use only torso part contour of the model to reconstruct whole shape. We optimize the model parameters by minimizing the difference between corresponding silhouettes by using a stochastic, derivative-free non-linear optimization method, CMA-ES.

  1. Virtual VMASC: A 3D Game Environment

    NASA Technical Reports Server (NTRS)

    Manepalli, Suchitra; Shen, Yuzhong; Garcia, Hector M.; Lawsure, Kaleen

    2010-01-01

    The advantages of creating interactive 3D simulations that allow viewing, exploring, and interacting with land improvements, such as buildings, in digital form are manifold and range from allowing individuals from anywhere in the world to explore those virtual land improvements online, to training military personnel in dealing with war-time environments, and to making those land improvements available in virtual worlds such as Second Life. While we haven't fully explored the true potential of such simulations, we have identified a requirement within our organization to use simulations like those to replace our front-desk personnel and allow visitors to query, naVigate, and communicate virtually with various entities within the building. We implemented the Virtual VMASC 3D simulation of the Virginia Modeling Analysis and Simulation Center (VMASC) office building to not only meet our front-desk requirement but also to evaluate the effort required in designing such a simulation and, thereby, leverage the experience we gained in future projects of this kind. This paper describes the goals we set for our implementation, the software approach taken, the modeling contribution made, and the technologies used such as XNA Game Studio, .NET framework, Autodesk software packages, and, finally, the applicability of our implementation on a variety of architectures including Xbox 360 and PC. This paper also summarizes the result of our evaluation and the lessons learned from our effort.

  2. 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.

  3. 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.

  4. Design and application of real-time visual attention model for the exploration of 3D virtual environments.

    PubMed

    Hillaire, Sébastien; Lécuyer, Anatole; Regia-Corte, Tony; Cozot, Rémi; Royan, Jérôme; Breton, Gaspard

    2012-03-01

    This paper studies the design and application of a novel visual attention model designed to compute user's gaze position automatically, i.e., without using a gaze-tracking system. The model we propose is specifically designed for real-time first-person exploration of 3D virtual environments. It is the first model adapted to this context which can compute in real time a continuous gaze point position instead of a set of 3D objects potentially observed by the user. To do so, contrary to previous models which use a mesh-based representation of visual objects, we introduce a representation based on surface-elements. Our model also simulates visual reflexes and the cognitive processes which take place in the brain such as the gaze behavior associated to first-person navigation in the virtual environment. Our visual attention model combines both bottom-up and top-down components to compute a continuous gaze point position on screen that hopefully matches the user's one. We conducted an experiment to study and compare the performance of our method with a state-of-the-art approach. Our results are found significantly better with sometimes more than 100 percent of accuracy gained. This suggests that computing a gaze point in a 3D virtual environment in real time is possible and is a valid approach, compared to object-based approaches. Finally, we expose different applications of our model when exploring virtual environments. We present different algorithms which can improve or adapt the visual feedback of virtual environments based on gaze information. We first propose a level-of-detail approach that heavily relies on multiple-texture sampling. We show that it is possible to use the gaze information of our visual attention model to increase visual quality where the user is looking, while maintaining a high-refresh rate. Second, we introduce the use of the visual attention model in three visual effects inspired by the human visual system namely: depth-of-field blur, camera

  5. Generic precise augmented reality guiding system and its calibration method based on 3D virtual model.

    PubMed

    Liu, Miao; Yang, Shourui; Wang, Zhangying; Huang, Shujun; Liu, Yue; Niu, Zhenqi; Zhang, Xiaoxuan; Zhu, Jigui; Zhang, Zonghua

    2016-05-30

    Augmented reality system can be applied to provide precise guidance for various kinds of manual works. The adaptability and guiding accuracy of such systems are decided by the computational model and the corresponding calibration method. In this paper, a novel type of augmented reality guiding system and the corresponding designing scheme are proposed. Guided by external positioning equipment, the proposed system can achieve high relative indication accuracy in a large working space. Meanwhile, the proposed system is realized with a digital projector and the general back projection model is derived with geometry relationship between digitized 3D model and the projector in free space. The corresponding calibration method is also designed for the proposed system to obtain the parameters of projector. To validate the proposed back projection model, the coordinate data collected by a 3D positioning equipment is used to calculate and optimize the extrinsic parameters. The final projecting indication accuracy of the system is verified with subpixel pattern projecting technique. PMID:27410124

  6. Identification of potential influenza virus endonuclease inhibitors through virtual screening based on the 3D-QSAR model.

    PubMed

    Kim, J; Lee, C; Chong, Y

    2009-01-01

    Influenza endonucleases have appeared as an attractive target of antiviral therapy for influenza infection. With the purpose of designing a novel antiviral agent with enhanced biological activities against influenza endonuclease, a three-dimensional quantitative structure-activity relationships (3D-QSAR) model was generated based on 34 influenza endonuclease inhibitors. The comparative molecular similarity index analysis (CoMSIA) with a steric, electrostatic and hydrophobic (SEH) model showed the best correlative and predictive capability (q(2) = 0.763, r(2) = 0.969 and F = 174.785), which provided a pharmacophore composed of the electronegative moiety as well as the bulky hydrophobic group. The CoMSIA model was used as a pharmacophore query in the UNITY search of the ChemDiv compound library to give virtual active compounds. The 3D-QSAR model was then used to predict the activity of the selected compounds, which identified three compounds as the most likely inhibitor candidates. PMID:19343586

  7. Three-dimensional immersive virtual reality for studying cellular compartments in 3D models from EM preparations of neural tissues.

    PubMed

    Calì, Corrado; Baghabra, Jumana; Boges, Daniya J; Holst, Glendon R; Kreshuk, Anna; Hamprecht, Fred A; Srinivasan, Madhusudhanan; Lehväslaiho, Heikki; Magistretti, Pierre J

    2016-01-01

    Advances in the application of electron microscopy (EM) to serial imaging are opening doors to new ways of analyzing cellular structure. New and improved algorithms and workflows for manual and semiautomated segmentation allow us to observe the spatial arrangement of the smallest cellular features with unprecedented detail in full three-dimensions. From larger samples, higher complexity models can be generated; however, they pose new challenges to data management and analysis. Here we review some currently available solutions and present our approach in detail. We use the fully immersive virtual reality (VR) environment CAVE (cave automatic virtual environment), a room in which we are able to project a cellular reconstruction and visualize in 3D, to step into a world created with Blender, a free, fully customizable 3D modeling software with NeuroMorph plug-ins for visualization and analysis of EM preparations of brain tissue. Our workflow allows for full and fast reconstructions of volumes of brain neuropil using ilastik, a software tool for semiautomated segmentation of EM stacks. With this visualization environment, we can walk into the model containing neuronal and astrocytic processes to study the spatial distribution of glycogen granules, a major energy source that is selectively stored in astrocytes. The use of CAVE was key to the observation of a nonrandom distribution of glycogen, and led us to develop tools to quantitatively analyze glycogen clustering and proximity to other subcellular features. PMID:26179415

  8. Pharmacophore modeling, virtual screening and 3D-QSAR studies of 5-tetrahydroquinolinylidine aminoguanidine derivatives as sodium hydrogen exchanger inhibitors.

    PubMed

    Bhatt, Hardik G; Patel, Paresh K

    2012-06-01

    Sodium hydrogen exchanger (SHE) inhibitor is one of the most important targets in treatment of myocardial ischemia. In the course of our research into new types of non-acylguanidine, SHE inhibitory activities of 5-tetrahydroquinolinylidine aminoguanidine derivatives were used to build pharmacophore and 3D-QSAR models. Genetic Algorithm Similarity Program (GASP) was used to derive a 3D pharmacophore model which was used in effective alignment of data set. Eight molecules were selected on the basis of structure diversity to build 10 different pharmacophore models. Model 1 was considered as the best model as it has highest fitness score compared to other nine models. The obtained model contained two acceptor sites, two donor atoms and one hydrophobic region. Pharmacophore modeling was followed by substructure searching and virtual screening. The best CoMFA model, representing steric and electrostatic fields, obtained for 30 training set molecules was statistically significant with cross-validated coefficient (q(2)) of 0.673 and conventional coefficient (r(2)) of 0.988. In addition to steric and electrostatic fields observed in CoMFA, CoMSIA also represents hydrophobic, hydrogen bond donor and hydrogen bond acceptor fields. CoMSIA model was also significant with cross-validated coefficient (q(2)) and conventional coefficient (r(2)) of 0.636 and 0.986, respectively. Both models were validated by an external test set of eight compounds and gave satisfactory prediction (r(pred)(2)) of 0.772 and 0.701 for CoMFA and CoMSIA models, respectively. This pharmacophore based 3D-QSAR approach provides significant insights that can be used to design novel, potent and selective SHE inhibitors. PMID:22546667

  9. 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…

  10. Determinants of Presence in 3D Virtual Worlds: A Structural Equation Modelling Analysis

    ERIC Educational Resources Information Center

    Chow, Meyrick

    2016-01-01

    There is a growing body of evidence that feeling present in virtual environments contributes to effective learning. Presence is a psychological state of the user; hence, it is generally agreed that individual differences in user characteristics can lead to different experiences of presence. Despite the fact that user characteristics can play a…

  11. Techniques for Revealing 3d Hidden Archeological Features: Morphological Residual Models as Virtual-Polynomial Texture Maps

    NASA Astrophysics Data System (ADS)

    Pires, H.; Martínez Rubio, J.; Elorza Arana, A.

    2015-02-01

    The recent developments in 3D scanning technologies are not been accompanied by visualization interfaces. We are still using the same types of visual codes as when maps and drawings were made by hand. The available information in 3D scanning data sets is not being fully exploited by current visualization techniques. In this paper we present recent developments regarding the use of 3D scanning data sets for revealing invisible information from archaeological sites. These sites are affected by a common problem, decay processes, such as erosion, that never ceases its action and endangers the persistence of last vestiges of some peoples and cultures. Rock art engravings, or epigraphical inscriptions, are among the most affected by these processes because they are, due to their one nature, carved at the surface of rocks often exposed to climatic agents. The study and interpretation of these motifs and texts is strongly conditioned by the degree of conservation of the imprints left by our ancestors. Every single detail in the remaining carvings can make a huge difference in the conclusions taken by specialists. We have selected two case-studies severely affected by erosion to present the results of the on-going work dedicated to explore in new ways the information contained in 3D scanning data sets. A new method for depicting subtle morphological features in the surface of objects or sites has been developed. It allows to contrast human patterns still present at the surface but invisible to naked eye or by any other archaeological inspection technique. It was called Morphological Residual Model (MRM) because of its ability to contrast the shallowest morphological details, to which we refer as residuals, contained in the wider forms of the backdrop. Afterwards, we have simulated the process of building Polynomial Texture Maps - a widespread technique that as been contributing to archaeological studies for some years - in a 3D virtual environment using the results of MRM

  12. 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. PMID:25808044

  13. 3D Virtual Reality for Teaching Astronomy

    NASA Astrophysics Data System (ADS)

    Speck, Angela; Ruzhitskaya, L.; Laffey, J.; Ding, N.

    2012-01-01

    We are developing 3D virtual learning environments (VLEs) as learning materials for an undergraduate astronomy course, in which will utilize advances both in technologies available and in our understanding of the social nature of learning. These learning materials will be used to test whether such VLEs can indeed augment science learning so that it is more engaging, active, visual and effective. Our project focuses on the challenges and requirements of introductory college astronomy classes. Here we present our virtual world of the Jupiter system and how we plan to implement it to allow 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 VLE can allow students to work individually or collaboratively. The 3D world also provides an 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 this VLE is also a valuable source for exploration of how the learners’ spatial awareness can be enhanced by working in 3D environment. We will present the Jupiter-system environment along with a preliminary study of the efficacy and usability of our Jupiter 3D VLE.

  14. [3D virtual endoscopy of heart].

    PubMed

    Du, Aan; Yang, Xin; Xue, Haihong; Yao, Liping; Sun, Kun

    2012-10-01

    In this paper, we present a virtual endoscopy (VE) for diagnosis of heart diseases, which is proved efficient and affordable, easy to popularize for viewing the interior of the heart. The dual source CT (DSCT) data were used as primary data in our system. The 3D structure of virtual heart was reconstructed with 3D texture mapping technology based on graphics processing unit (GPU), and could be displayed dynamically in real time. When we displayed it in real time, we could not only observe the inside of the chambers of heart but also examine from the new angle of view by the 3D data which were already clipped according to doctor's desire. In the pattern of observation, we used both mutual interactive mode and auto mode. In the auto mode, we used Dijkstra Algorithm which treated the 3D Euler distance as weighting factor to find out the view path quickly, and, used view path to calculate the four chamber plane. PMID:23198444

  15. 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.

  16. 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.

  17. Consultation virtual collaborative environment for 3D medicine.

    PubMed

    Krsek, Premysl; Spanel, Michal; Svub, Miroslav; Stancl, Vít; Siler, Ondrej; Sára, Vítezslav

    2008-01-01

    This article focuses on the problems of consultation virtual collaborative environment, which is designed to support 3D medical applications. This system allows loading CT/MR data from PACS system, segmentation and 3D models of tissues. It allows distant 3D consultations of the data between technicians and surgeons. System is designed as three-layer client-server architecture. Communication between clients and server is done via HTTP/HTTPS protocol. Results and tests have confirmed, that today's standard network latency and dataflow do not affect the usability of our system. PMID:19162770

  18. 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.

  19. Virtualizing ancient Rome: 3D acquisition and modeling of a large plaster-of-Paris model of imperial Rome

    NASA Astrophysics Data System (ADS)

    Guidi, Gabriele; Frischer, Bernard; De Simone, Monica; Cioci, Andrea; Spinetti, Alessandro; Carosso, Luca; Micoli, Laura L.; Russo, Michele; Grasso, Tommaso

    2005-01-01

    Computer modeling through digital range images has been used for many applications, including 3D modeling of objects belonging to our cultural heritage. The scales involved range from small objects (e.g. pottery), to middle-sized works of art (statues, architectural decorations), up to very large structures (architectural and archaeological monuments). For any of these applications, suitable sensors and methodologies have been explored by different authors. The object to be modeled within this project is the "Plastico di Roma antica," a large plaster-of-Paris model of imperial Rome (16x17 meters) created in the last century. Its overall size therefore demands an acquisition approach typical of large structures, but it also is characterized extremely tiny details typical of small objects (houses are a few centimeters high; their doors, windows, etc. are smaller than 1 centimeter). This paper gives an account of the procedures followed for solving this "contradiction" and describes how a huge 3D model was acquired and generated by using a special metrology Laser Radar. The procedures for reorienting in a single reference system the huge point clouds obtained after each acquisition phase, thanks to the measurement of fixed redundant references, are described. The data set was split in smaller sub-areas 2 x 2 meters each for purposes of mesh editing. This subdivision was necessary owing to the huge number of points in each individual scan (50-60 millions). The final merge of the edited parts made it possible to create a single mesh. All these processes were made with software specifically designed for this project since no commercial package could be found that was suitable for managing such a large number of points. Preliminary models are presented. Finally, the significance of the project is discussed in terms of the overall project known as "Rome Reborn," of which the present acquisition is an important component.

  20. Virtualizing ancient Rome: 3D acquisition and modeling of a large plaster-of-Paris model of imperial Rome

    NASA Astrophysics Data System (ADS)

    Guidi, Gabriele; Frischer, Bernard; De Simone, Monica; Cioci, Andrea; Spinetti, Alessandro; Carosso, Luca; Micoli, Laura L.; Russo, Michele; Grasso, Tommaso

    2004-12-01

    Computer modeling through digital range images has been used for many applications, including 3D modeling of objects belonging to our cultural heritage. The scales involved range from small objects (e.g. pottery), to middle-sized works of art (statues, architectural decorations), up to very large structures (architectural and archaeological monuments). For any of these applications, suitable sensors and methodologies have been explored by different authors. The object to be modeled within this project is the "Plastico di Roma antica," a large plaster-of-Paris model of imperial Rome (16x17 meters) created in the last century. Its overall size therefore demands an acquisition approach typical of large structures, but it also is characterized extremely tiny details typical of small objects (houses are a few centimeters high; their doors, windows, etc. are smaller than 1 centimeter). This paper gives an account of the procedures followed for solving this "contradiction" and describes how a huge 3D model was acquired and generated by using a special metrology Laser Radar. The procedures for reorienting in a single reference system the huge point clouds obtained after each acquisition phase, thanks to the measurement of fixed redundant references, are described. The data set was split in smaller sub-areas 2 x 2 meters each for purposes of mesh editing. This subdivision was necessary owing to the huge number of points in each individual scan (50-60 millions). The final merge of the edited parts made it possible to create a single mesh. All these processes were made with software specifically designed for this project since no commercial package could be found that was suitable for managing such a large number of points. Preliminary models are presented. Finally, the significance of the project is discussed in terms of the overall project known as "Rome Reborn," of which the present acquisition is an important component.

  1. The use of a low-cost visible light 3D scanner to create virtual reality environment models of actors and objects

    NASA Astrophysics Data System (ADS)

    Straub, Jeremy

    2015-05-01

    A low-cost 3D scanner has been developed with a parts cost of approximately USD $5,000. This scanner uses visible light sensing to capture both structural as well as texture and color data of a subject. This paper discusses the use of this type of scanner to create 3D models for incorporation into a virtual reality environment. It describes the basic scanning process (which takes under a minute for a single scan), which can be repeated to collect multiple positions, if needed for actor model creation. The efficacy of visible light versus other scanner types is also discussed.

  2. Cognitive Aspects of Collaboration in 3d Virtual Environments

    NASA Astrophysics Data System (ADS)

    Juřík, V.; Herman, L.; Kubíček, P.; Stachoň, Z.; Šašinka, Č.

    2016-06-01

    Human-computer interaction has entered the 3D era. The most important models representing spatial information — maps — are transferred into 3D versions regarding the specific content to be displayed. Virtual worlds (VW) become promising area of interest because of possibility to dynamically modify content and multi-user cooperation when solving tasks regardless to physical presence. They can be used for sharing and elaborating information via virtual images or avatars. Attractiveness of VWs is emphasized also by possibility to measure operators' actions and complex strategies. Collaboration in 3D environments is the crucial issue in many areas where the visualizations are important for the group cooperation. Within the specific 3D user interface the operators' ability to manipulate the displayed content is explored regarding such phenomena as situation awareness, cognitive workload and human error. For such purpose, the VWs offer a great number of tools for measuring the operators' responses as recording virtual movement or spots of interest in the visual field. Study focuses on the methodological issues of measuring the usability of 3D VWs and comparing them with the existing principles of 2D maps. We explore operators' strategies to reach and interpret information regarding the specific type of visualization and different level of immersion.

  3. Learning in 3-D Virtual Worlds: Rethinking Media Literacy

    ERIC Educational Resources Information Center

    Qian, Yufeng

    2008-01-01

    3-D virtual worlds, as a new form of learning environments in the 21st century, hold great potential in education. Learning in such environments, however, demands a broader spectrum of literacy skills. This article identifies a new set of media literacy skills required in 3-D virtual learning environments by reviewing exemplary 3-D virtual…

  4. Building Analysis for Urban Energy Planning Using Key Indicators on Virtual 3d City Models - the Energy Atlas of Berlin

    NASA Astrophysics Data System (ADS)

    Krüger, A.; Kolbe, T. H.

    2012-07-01

    In the context of increasing greenhouse gas emission and global demographic change with the simultaneous trend to urbanization, it is a big challenge for cities around the world to perform modifications in energy supply chain and building characteristics resulting in reduced energy consumption and carbon dioxide mitigation. Sound knowledge of energy resource demand and supply including its spatial distribution within urban areas is of great importance for planning strategies addressing greater energy efficiency. The understanding of the city as a complex energy system affects several areas of the urban living, e.g. energy supply, urban texture, human lifestyle, and climate protection. With the growing availability of 3D city models around the world based on the standard language and format CityGML, energy system modelling, analysis and simulation can be incorporated into these models. Both domains will profit from that interaction by bringing together official and accurate building models including building geometries, semantics and locations forming a realistic image of the urban structure with systemic energy simulation models. A holistic view on the impacts of energy planning scenarios can be modelled and analyzed including side effects on urban texture and human lifestyle. This paper focuses on the identification, classification, and integration of energy-related key indicators of buildings and neighbourhoods within 3D building models. Consequent application of 3D city models conforming to CityGML serves the purpose of deriving indicators for this topic. These will be set into the context of urban energy planning within the Energy Atlas Berlin. The generation of indicator objects covering the indicator values and related processing information will be presented on the sample scenario estimation of heating energy consumption in buildings and neighbourhoods. In their entirety the key indicators will form an adequate image of the local energy situation for

  5. 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…

  6. 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.

  7. Virtual environment display for a 3D audio room simulation

    NASA Technical Reports Server (NTRS)

    Chapin, William L.; Foster, Scott H.

    1992-01-01

    The development of a virtual environment simulation system integrating a 3D acoustic audio model with an immersive 3D visual scene is discussed. The system complements the acoustic model and is specified to: allow the listener to freely move about the space, a room of manipulable size, shape, and audio character, while interactively relocating the sound sources; reinforce the listener's feeling of telepresence in the acoustical environment with visual and proprioceptive sensations; enhance the audio with the graphic and interactive components, rather than overwhelm or reduce it; and serve as a research testbed and technology transfer demonstration. The hardware/software design of two demonstration systems, one installed and one portable, are discussed through the development of four iterative configurations.

  8. Development of microgravity, full body functional reach envelope using 3-D computer graphic models and virtual reality technology

    NASA Technical Reports Server (NTRS)

    Lindsey, Patricia F.

    1994-01-01

    In microgravity conditions mobility is greatly enhanced and body stability is difficult to achieve. Because of these difficulties, optimum placement and accessibility of objects and controls can be critical to required tasks on board shuttle flights or on the proposed space station. Anthropometric measurement of the maximum reach of occupants of a microgravity environment provide knowledge about maximum functional placement for tasking situations. Calculations for a full body, functional reach envelope for microgravity environments are imperative. To this end, three dimensional computer modeled human figures, providing a method of anthropometric measurement, were used to locate the data points that define the full body, functional reach envelope. Virtual reality technology was utilized to enable an occupant of the microgravity environment to experience movement within the reach envelope while immersed in a simulated microgravity environment.

  9. 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

  10. In silico exploration of c-KIT inhibitors by pharmaco-informatics methodology: pharmacophore modeling, 3D QSAR, docking studies, and virtual screening.

    PubMed

    Chaudhari, Prashant; Bari, Sanjay

    2016-02-01

    c-KIT is a component of the platelet-derived growth factor receptor family, classified as type-III receptor tyrosine kinase. c-KIT has been reported to be involved in, small cell lung cancer, other malignant human cancers, and inflammatory and autoimmune diseases associated with mast cells. Available c-KIT inhibitors suffer from tribulations of growing resistance or cardiac toxicity. A combined in silico pharmacophore and structure-based virtual screening was performed to identify novel potential c-KIT inhibitors. In the present study, five molecules from the ZINC database were retrieved as new potential c-KIT inhibitors, using Schrödinger's Maestro 9.0 molecular modeling suite. An atom-featured 3D QSAR model was built using previously reported c-KIT inhibitors containing the indolin-2-one scaffold. The developed 3D QSAR model ADHRR.24 was found to be significant (R2 = 0.9378, Q2 = 0.7832) and instituted to be sufficiently robust with good predictive accuracy, as confirmed through external validation approaches, Y-randomization and GH approach [GH score 0.84 and Enrichment factor (E) 4.964]. The present QSAR model was further validated for the OECD principle 3, in that the applicability domain was calculated using a "standardization approach." Molecular docking of the QSAR dataset molecules and final ZINC hits were performed on the c-KIT receptor (PDB ID: 3G0E). Docking interactions were in agreement with the developed 3D QSAR model. Model ADHRR.24 was explored for ligand-based virtual screening followed by in silico ADME prediction studies. Five molecules from the ZINC database were obtained as potential c-KIT inhibitors with high in -silico predicted activity and strong key binding interactions with the c-KIT receptor. PMID:26416560

  11. 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…

  12. What Are the Learning Affordances of 3-D Virtual Environments?

    ERIC Educational Resources Information Center

    Dalgarno, Barney; Lee, Mark J. W.

    2010-01-01

    This article explores the potential learning benefits of three-dimensional (3-D) virtual learning environments (VLEs). Drawing on published research spanning two decades, it identifies a set of unique characteristics of 3-D VLEs, which includes aspects of their representational fidelity and aspects of the learner-computer interactivity they…

  13. 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…

  14. 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

  15. 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…

  16. Improvements in education in pathology: virtual 3D specimens.

    PubMed

    Kalinski, Thomas; Zwönitzer, Ralf; Jonczyk-Weber, Thomas; Hofmann, Harald; Bernarding, Johannes; Roessner, Albert

    2009-01-01

    Virtual three-dimensional (3D) specimens correspond to 3D visualizations of real pathological specimens on a computer display. We describe a simple method for the digitalization of such specimens from high-quality digital images. The images were taken during a whole rotation of a specimen, and merged together into a JPEG2000 multi-document file. The files were made available in the internet (http://patho.med.uni-magdeburg.de/research.shtml) and obtained very positive ratings by medical students. Virtual 3D specimens expand the application of digital techniques in pathology, and will contribute significantly to the successful introduction of knowledge databases and electronic learning platforms. PMID:19457621

  17. The virtual reality 3D city of Ningbo

    NASA Astrophysics Data System (ADS)

    Chen, Weimin; Wu, Dun

    2009-09-01

    In 2005, Ningbo Design Research Institute of Mapping & Surveying started the development of concepts and an implementation of Virtual Reality Ningbo System (VRNS). VRNS is being developed under the digital city technological framework and well supported by computing advances, space technologies, and commercial innovations. It has become the best solution for integrating, managing, presenting, and distributing complex city information. VRNS is not only a 3D-GIS launch project but also a technology innovation. The traditional domain of surveying and mapping has changed greatly in Ningbo. Geo-information systems are developing towards a more reality-, three dimension- and Service-Oriented Architecture-based system. The VRNS uses technology such as 3D modeling, user interface design, view scene modeling, real-time rendering and interactive roaming under a virtual environment. Two applications of VRNS already being used are for city planning and high-rise buildings' security management. The final purpose is to develop VRNS into a powerful public information platform, and to achieve that heterogeneous city information resources share this one single platform.

  18. The virtual reality 3D city of Ningbo

    NASA Astrophysics Data System (ADS)

    Chen, Weimin; Wu, Dun

    2010-11-01

    In 2005, Ningbo Design Research Institute of Mapping & Surveying started the development of concepts and an implementation of Virtual Reality Ningbo System (VRNS). VRNS is being developed under the digital city technological framework and well supported by computing advances, space technologies, and commercial innovations. It has become the best solution for integrating, managing, presenting, and distributing complex city information. VRNS is not only a 3D-GIS launch project but also a technology innovation. The traditional domain of surveying and mapping has changed greatly in Ningbo. Geo-information systems are developing towards a more reality-, three dimension- and Service-Oriented Architecture-based system. The VRNS uses technology such as 3D modeling, user interface design, view scene modeling, real-time rendering and interactive roaming under a virtual environment. Two applications of VRNS already being used are for city planning and high-rise buildings' security management. The final purpose is to develop VRNS into a powerful public information platform, and to achieve that heterogeneous city information resources share this one single platform.

  19. 3D Reconstruction of virtual colon structures from colonoscopy images.

    PubMed

    Hong, DongHo; Tavanapong, Wallapak; Wong, Johnny; Oh, JungHwan; de Groen, Piet C

    2014-01-01

    This paper presents the first fully automated reconstruction technique of 3D virtual colon segments from individual colonoscopy images. It is the basis of new software applications that may offer great benefits for improving quality of care for colonoscopy patients. For example, a 3D map of the areas inspected and uninspected during colonoscopy can be shown on request of the endoscopist during the procedure. The endoscopist may revisit the suggested uninspected areas to reduce the chance of missing polyps that reside in these areas. The percentage of the colon surface seen by the endoscopist can be used as a coarse objective indicator of the quality of the procedure. The derived virtual colon models can be stored for post-procedure training of new endoscopists to teach navigation techniques that result in a higher level of procedure quality. Our technique does not require a prior CT scan of the colon or any global positioning device. Our experiments on endoscopy images of an Olympus synthetic colon model reveal encouraging results with small average reconstruction errors (4.1 mm for the fold depths and 12.1 mm for the fold circumferences). PMID:24225230

  20. 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…

  1. Making Inexpensive 3-D Models

    ERIC Educational Resources Information Center

    Manos, Harry

    2016-01-01

    Visual aids are important to student learning, and they help make the teacher's job easier. Keeping with the "TPT" theme of "The Art, Craft, and Science of Physics Teaching," the purpose of this article is to show how teachers, lacking equipment and funds, can construct a durable 3-D model reference frame and a model gravity…

  2. Identifying Virtual 3D Geometric Shapes with a Vibrotactile Glove.

    PubMed

    Martínez, Jonatan; García, Arturo; Oliver, Miguel; Molina, José Pascual; González, Pascual

    2016-01-01

    The emergence of off-screen interaction devices is bringing the field of virtual reality to a broad range of applications where virtual objects can be manipulated without the use of traditional peripherals. However, to facilitate object interaction, other stimuli such as haptic feedback are necessary to improve the user experience. To enable the identification of virtual 3D objects without visual feedback, a haptic display based on a vibrotactile glove and multiple points of contact gives users an enhanced sensation of touching a virtual object with their hands. Experimental results demonstrate the capacity of this technology in practical applications. PMID:25137722

  3. [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. PMID:24804488

  4. 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.

  5. Three Dimensional (3D) Printing: A Straightforward, User-Friendly Protocol to Convert Virtual Chemical Models to Real-Life Objects

    ERIC Educational Resources Information Center

    Rossi, Sergio; Benaglia, Maurizio; Brenna, Davide; Porta, Riccardo; Orlandi, Manuel

    2015-01-01

    A simple procedure to convert protein data bank files (.pdb) into a stereolithography file (.stl) using VMD software (Virtual Molecular Dynamic) is reported. This tutorial allows generating, with a very simple protocol, three-dimensional customized structures that can be printed by a low-cost 3D-printer, and used for teaching chemical education…

  6. Modeling and Accuracy Assessment for 3D-VIRTUAL Reconstruction in Cultural Heritage Using Low-Cost Photogrammetry: Surveying of the "santa MARÍA Azogue" Church's Front

    NASA Astrophysics Data System (ADS)

    Robleda Prieto, G.; Pérez Ramos, A.

    2015-02-01

    Sometimes it could be difficult to represent "on paper" an architectural idea, a solution, a detail or a newly created element, depending on the complexity what it want be conveyed through its graphical representation but it may be even harder to represent the existing reality. (a building, a detail,...), at least with an acceptable degree of definition and accuracy. As a solution to this hypothetical problem, this paper try to show a methodology to collect measure data by combining different methods or techniques, to obtain the characteristic geometry of architectonic elements, especially in those highly decorated and/or complex geometry, as well as to assess the accuracy of the results obtained, but in an accuracy level enough and not very expensive costs. In addition, we can obtain a 3D recovery model that allows us a strong support, beyond point clouds obtained through another more expensive methods as using laser scanner, to obtain orthoimages. This methodology was used in the study case of the 3D-virtual reconstruction of a main medieval church façade because of the geometrical complexity in many elements as the existing main doorway with archivolts and many details, as well as the rose window located above it so it's inaccessible due to the height.

  7. 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…

  8. Virtual environment display for a 3D audio room simulation

    NASA Astrophysics Data System (ADS)

    Chapin, William L.; Foster, Scott

    1992-06-01

    Recent developments in virtual 3D audio and synthetic aural environments have produced a complex acoustical room simulation. The acoustical simulation models a room with walls, ceiling, and floor of selected sound reflecting/absorbing characteristics and unlimited independent localizable sound sources. This non-visual acoustic simulation, implemented with 4 audio ConvolvotronsTM by Crystal River Engineering and coupled to the listener with a Poihemus IsotrakTM, tracking the listener's head position and orientation, and stereo headphones returning binaural sound, is quite compelling to most listeners with eyes closed. This immersive effect should be reinforced when properly integrated into a full, multi-sensory virtual environment presentation. This paper discusses the design of an interactive, visual virtual environment, complementing the acoustic model and specified to: 1) allow the listener to freely move about the space, a room of manipulable size, shape, and audio character, while interactively relocating the sound sources; 2) reinforce the listener's feeling of telepresence into the acoustical environment with visual and proprioceptive sensations; 3) enhance the audio with the graphic and interactive components, rather than overwhelm or reduce it; and 4) serve as a research testbed and technology transfer demonstration. The hardware/software design of two demonstration systems, one installed and one portable, are discussed through the development of four iterative configurations. The installed system implements a head-coupled, wide-angle, stereo-optic tracker/viewer and multi-computer simulation control. The portable demonstration system implements a head-mounted wide-angle, stereo-optic display, separate head and pointer electro-magnetic position trackers, a heterogeneous parallel graphics processing system, and object oriented C++ program code.

  9. Measuring Knowledge Acquisition in 3D Virtual Learning Environments.

    PubMed

    Nunes, Eunice P dos Santos; Roque, Licínio G; Nunes, Fatima de Lourdes dos Santos

    2016-01-01

    Virtual environments can contribute to the effective learning of various subjects for people of all ages. Consequently, they assist in reducing the cost of maintaining physical structures of teaching, such as laboratories and classrooms. However, the measurement of how learners acquire knowledge in such environments is still incipient in the literature. This article presents a method to evaluate the knowledge acquisition in 3D virtual learning environments (3D VLEs) by using the learner's interactions in the VLE. Three experiments were conducted that demonstrate the viability of using this method and its computational implementation. The results suggest that it is possible to automatically assess learning in predetermined contexts and that some types of user interactions in 3D VLEs are correlated with the user's learning differential. PMID:26915117

  10. 3D virtual colonoscopy with real-time volume rendering

    NASA Astrophysics Data System (ADS)

    Wan, Ming; Li, Wei J.; Kreeger, Kevin; Bitter, Ingmar; Kaufman, Arie E.; Liang, Zhengrong; Chen, Dongqing; Wax, Mark R.

    2000-04-01

    In our previous work, we developed a virtual colonoscopy system on a high-end 16-processor SGI Challenge with an expensive hardware graphics accelerator. The goal of this work is to port the system to a low cost PC in order to increase its availability for mass screening. Recently, Mitsubishi Electric has developed a volume-rendering PC board, called VolumePro, which includes 128 MB of RAM and vg500 rendering chip. The vg500 chip, based on Cube-4 technology, can render a 2563 volume at 30 frames per second. High image quality of volume rendering inside the colon is guaranteed by the full lighting model and 3D interpolation supported by the vg500 chip. However, the VolumePro board is lacking some features required by our interactive colon navigation. First, VolumePro currently does not support perspective projection which is paramount for interior colon navigation. Second, the patient colon data is usually much larger than 2563 and cannot be rendered in real-time. In this paper, we present our solutions to these problems, including simulated perspective projection and axis aligned boxing techniques, and demonstrate the high performance of our virtual colonoscopy system on low cost PCs.

  11. Acoustic simulation in realistic 3D virtual scenes

    NASA Astrophysics Data System (ADS)

    Gozard, Patrick; Le Goff, Alain; Naz, Pierre; Cathala, Thierry; Latger, Jean

    2003-09-01

    The simulation workshop CHORALE developed in collaboration with OKTAL SE company for the French MoD is used by government services and industrial companies for weapon system validation and qualification trials in the infrared domain. The main operational reference for CHORALE is the assessment of the infrared guidance system of the Storm Shadow missile French version, called Scalp. The use of CHORALE workshop is now extended to the acoustic domain. The main objective is the simulation of the detection of moving vehicles in realistic 3D virtual scenes. This article briefly describes the acoustic model in CHORALE. The 3D scene is described by a set of polygons. Each polygon is characterized by its acoustic resistivity or its complex impedance. Sound sources are associated with moving vehicles and are characterized by their spectra and directivities. A microphone sensor is defined by its position, its frequency band and its sensitivity. The purpose of the acoustic simulation is to calculate the incoming acoustic pressure on microphone sensors. CHORALE is based on a generic ray tracing kernel. This kernel possesses original capabilities: computation time is nearly independent on the scene complexity, especially the number of polygons, databases are enhanced with precise physical data, special mechanisms of antialiasing have been developed that enable to manage very accurate details. The ray tracer takes into account the wave geometrical divergence and the atmospheric transmission. The sound wave refraction is simulated and rays cast in the 3D scene are curved according to air temperature gradient. Finally, sound diffraction by edges (hill, wall,...) is also taken into account.

  12. Virtual view adaptation for 3D multiview video streaming

    NASA Astrophysics Data System (ADS)

    Petrovic, Goran; Do, Luat; Zinger, Sveta; de With, Peter H. N.

    2010-02-01

    Virtual views in 3D-TV and multi-view video systems are reconstructed images of the scene generated synthetically from the original views. In this paper, we analyze the performance of streaming virtual views over IP-networks with a limited and time-varying available bandwidth. We show that the average video quality perceived by the user can be improved with an adaptive streaming strategy aiming at maximizing the average video quality. Our adaptive 3D multi-view streaming can provide a quality improvement of 2 dB on the average - over non-adaptive streaming. We demonstrate that an optimized virtual view adaptation algorithm needs to be view-dependent and achieve an improvement of up to 0.7 dB. We analyze our adaptation strategies under dynamic available bandwidth in the network.

  13. Illustrative visualization of 3D city models

    NASA Astrophysics Data System (ADS)

    Doellner, Juergen; Buchholz, Henrik; Nienhaus, Marc; Kirsch, Florian

    2005-03-01

    This paper presents an illustrative visualization technique that provides expressive representations of large-scale 3D city models, inspired by the tradition of artistic and cartographic visualizations typically found in bird"s-eye view and panoramic maps. We define a collection of city model components and a real-time multi-pass rendering algorithm that achieves comprehensible, abstract 3D city model depictions based on edge enhancement, color-based and shadow-based depth cues, and procedural facade texturing. Illustrative visualization provides an effective visual interface to urban spatial information and associated thematic information complementing visual interfaces based on the Virtual Reality paradigm, offering a huge potential for graphics design. Primary application areas include city and landscape planning, cartoon worlds in computer games, and tourist information systems.

  14. Making Inexpensive 3-D Models

    NASA Astrophysics Data System (ADS)

    Manos, Harry

    2016-03-01

    Visual aids are important to student learning, and they help make the teacher's job easier. Keeping with the TPT theme of "The Art, Craft, and Science of Physics Teaching," the purpose of this article is to show how teachers, lacking equipment and funds, can construct a durable 3-D model reference frame and a model gravity well tailored to specific class lessons. Most of the supplies are readily available in the home or at school: rubbing alcohol, a rag, two colors of spray paint, art brushes, and masking tape. The cost of these supplies, if you don't have them, is less than 20.

  15. A common feature-based 3D-pharmacophore model generation and virtual screening: identification of potential PfDHFR inhibitors.

    PubMed

    Adane, Legesse; Bharatam, Prasad V; Sharma, Vikas

    2010-10-01

    A four-feature 3D-pharmacophore model was built from a set of 24 compounds whose activities were reported against the V1/S strain of the Plasmodium falciparum dihydrofolate reductase (PfDHFR) enzyme. This is an enzyme harboring Asn51Ile + Cys59Arg + Ser108Asn + Ile164Leu mutations. The HipHop module of the Catalyst program was used to generate the model. Selection of the best model among the 10 hypotheses generated by HipHop was carried out based on rank and best-fit values or alignments of the training set compounds onto a particular hypothesis. The best model (hypo1) consisted of two H-bond donors, one hydrophobic aromatic, and one hydrophobic aliphatic features. Hypo1 was used as a query to virtually screen Maybridge2004 and NCI2000 databases. The hits obtained from the search were subsequently subjected to FlexX and Glide docking studies. Based on the binding scores and interactions in the active site of quadruple-mutant PfDHFR, a set of nine hits were identified as potential inhibitors. PMID:19995305

  16. Inertial Motion-Tracking Technology for Virtual 3-D

    NASA Technical Reports Server (NTRS)

    2005-01-01

    In the 1990s, NASA pioneered virtual reality research. The concept was present long before, but, prior to this, the technology did not exist to make a viable virtual reality system. Scientists had theories and ideas they knew that the concept had potential, but the computers of the 1970s and 1980s were not fast enough, sensors were heavy and cumbersome, and people had difficulty blending fluidly with the machines. Scientists at Ames Research Center built upon the research of previous decades and put the necessary technology behind them, making the theories of virtual reality a reality. Virtual reality systems depend on complex motion-tracking sensors to convey information between the user and the computer to give the user the feeling that he is operating in the real world. These motion-tracking sensors measure and report an object s position and orientation as it changes. A simple example of motion tracking would be the cursor on a computer screen moving in correspondence to the shifting of the mouse. Tracking in 3-D, necessary to create virtual reality, however, is much more complex. To be successful, the perspective of the virtual image seen on the computer must be an accurate representation of what is seen in the real world. As the user s head or camera moves, turns, or tilts, the computer-generated environment must change accordingly with no noticeable lag, jitter, or distortion. Historically, the lack of smooth and rapid tracking of the user s motion has thwarted the widespread use of immersive 3-D computer graphics. NASA uses virtual reality technology for a variety of purposes, mostly training of astronauts. The actual missions are costly and dangerous, so any opportunity the crews have to practice their maneuvering in accurate situations before the mission is valuable and instructive. For that purpose, NASA has funded a great deal of virtual reality research, and benefited from the results.

  17. Spilling the beans on java 3D: a tool for the virtual anatomist.

    PubMed

    Guttmann, G D

    1999-04-15

    The computing world has just provided the anatomist with another tool: Java 3D, within the Java 2 platform. On December 9, 1998, Sun Microsystems released Java 2. Java 3D classes are now included in the jar (Java Archive) archives of the extensions directory of Java 2. Java 3D is also a part of the Java Media Suite of APIs (Application Programming Interfaces). But what is Java? How does Java 3D work? How do you view Java 3D objects? A brief introduction to the concepts of Java and object-oriented programming is provided. Also, there is a short description of the tools of Java 3D and of the Java 3D viewer. Thus, the virtual anatomist has another set of computer tools to use for modeling various aspects of anatomy, such as embryological development. Also, the virtual anatomist will be able to assist the surgeon with virtual surgery using the tools found in Java 3D. Java 3D will be able to fulfill gaps, such as the lack of platform independence, interactivity, and manipulability of 3D images, currently existing in many anatomical computer-aided learning programs. PMID:10321435

  18. Virtual image display as a backlight for 3D.

    PubMed

    Travis, Adrian; MacCrann, Niall; Emerton, Neil; Kollin, Joel; Georgiou, Andreas; Lanier, Jaron; Bathiche, Stephen

    2013-07-29

    We describe a device which has the potential to be used both as a virtual image display and as a backlight. The pupil of the emitted light fills the device approximately to its periphery and the collimated emission can be scanned both horizontally and vertically in the manner needed to illuminate an eye in any position. The aim is to reduce the power needed to illuminate a liquid crystal panel but also to enable a smooth transition from 3D to a virtual image as the user nears the screen. PMID:23938645

  19. The Development of a Virtual 3D Model of the Renal Corpuscle from Serial Histological Sections for E-Learning Environments

    ERIC Educational Resources Information Center

    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…

  20. 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.

  1. 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.

  2. 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.

  3. 2.5D/3D Models for the enhancement of architectural-urban heritage. An Virtual Tour of design of the Fascist headquarters in Littoria

    NASA Astrophysics Data System (ADS)

    Ippoliti, E.; Calvano, M.; Mores, L.

    2014-05-01

    Enhancement of cultural heritage is not simply a matter of preserving material objects but comes full circle only when the heritage can be enjoyed and used by the community. This is the rationale behind this presentation: an urban Virtual Tour to explore the 1937 design of the Fascist Headquarters in Littoria, now part of Latina, by the architect Oriolo Frezzotti. Although the application is deliberately "simple", it was part of a much broader framework of goals. One such goal was to create "friendly and perceptively meaningful" interfaces by integrating different "3D models" and so enriching. In fact, by exploiting the activation of natural mechanisms of visual perception and the ensuing emotional emphasis associated with vision, the illusionistic simulation of the scene facilitates access to the data even for "amateur" users. A second goal was to "contextualise the information" on which the concept of cultural heritage is based. In the application, communication of the heritage is linked to its physical and linguistic context; the latter is then used as a basis from which to set out to explore and understand the historical evidence. A third goal was to foster the widespread dissemination and sharing of this heritage of knowledge. On the one hand we worked to make the application usable from the Web, on the other, we established a reliable, rapid operational procedure with high quality processed data and ensuing contents. The procedure was also repeatable on a large scale.

  4. Modular 3-D Transport model

    EPA Science Inventory

    MT3D was first developed by Chunmiao Zheng in 1990 at S.S. Papadopulos & Associates, Inc. with partial support from the U.S. Environmental Protection Agency (USEPA). Starting in 1990, MT3D was released as a pubic domain code from the USEPA. Commercial versions with enhanced capab...

  5. Crowdsourcing Based 3d Modeling

    NASA Astrophysics Data System (ADS)

    Somogyi, A.; Barsi, A.; Molnar, B.; Lovas, T.

    2016-06-01

    Web-based photo albums that support organizing and viewing the users' images are widely used. These services provide a convenient solution for storing, editing and sharing images. In many cases, the users attach geotags to the images in order to enable using them e.g. in location based applications on social networks. Our paper discusses a procedure that collects open access images from a site frequently visited by tourists. Geotagged pictures showing the image of a sight or tourist attraction are selected and processed in photogrammetric processing software that produces the 3D model of the captured object. For the particular investigation we selected three attractions in Budapest. To assess the geometrical accuracy, we used laser scanner and DSLR as well as smart phone photography to derive reference values to enable verifying the spatial model obtained from the web-album images. The investigation shows how detailed and accurate models could be derived applying photogrammetric processing software, simply by using images of the community, without visiting the site.

  6. Gravity and spatial orientation in virtual 3D-mazes.

    PubMed

    Vidal, Manuel; Lipshits, Mark; McIntyre, Joseph; Berthoz, Alain

    2003-01-01

    In order to bring new insights into the processing of 3D spatial information, we conducted experiments on the capacity of human subjects to memorize 3D-structured environments, such as buildings with several floors or the potentially complex 3D structure of an orbital space station. We had subjects move passively in one of two different exploration modes, through a visual virtual environment that consisted of a series of connected tunnels. In upright displacement, self-rotation when going around corners in the tunnels was limited to yaw rotations. For horizontal translations, subjects faced forward in the direction of motion. When moving up or down through vertical segments of the 3D tunnels, however, subjects facing the tunnel wall, remaining upright as if moving up and down in a glass elevator. In the unconstrained displacement mode, subjects would appear to climb or dive face-forward when moving vertically; thus, in this mode subjects could experience visual flow consistent with rotations about any of the 3 canonical axes. In a previous experiment, subjects were asked to determine whether a static, outside view of a test tunnel corresponded or not to the tunnel through which they had just passed. Results showed that performance was better on this task for the upright than for the unconstrained displacement mode; i.e. when subjects remained "upright" with respect to the virtual environment as defined by subject's posture in the first segment. This effect suggests that gravity may provide a key reference frame used in the shift between egocentric and allocentric representations of the 3D virtual world. To check whether it is the polarizing effects of gravity that leads to the favoring of the upright displacement mode, the experimental paradigm was adapted for orbital flight and performed by cosmonauts onboard the International Space Station. For these flight experiments the previous recognition task was replaced by a computerized reconstruction task, which proved

  7. 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.

  8. Virtual reality 3D headset based on DMD light modulators

    SciTech Connect

    Bernacki, Bruce E.; Evans, Allan; Tang, Edward

    2014-06-13

    We present the design of an immersion-type 3D headset suitable for virtual reality applications based upon digital micro-mirror devices (DMD). Our approach leverages silicon micro mirrors offering 720p resolution displays in a small form-factor. Supporting chip sets allow rapid integration of these devices into wearable displays with high resolution and low power consumption. Applications include night driving, piloting of UAVs, fusion of multiple sensors for pilots, training, vision diagnostics and consumer gaming. Our design is described in which light from the DMD is imaged to infinity and the user’s own eye lens forms a real image on the user’s retina.

  9. From Multi-User Virtual Environment to 3D Virtual Learning Environment

    ERIC Educational Resources Information Center

    Livingstone, Daniel; Kemp, Jeremy; Edgar, Edmund

    2008-01-01

    While digital virtual worlds have been used in education for a number of years, advances in the capabilities and spread of technology have fed a recent boom in interest in massively multi-user 3D virtual worlds for entertainment, and this in turn has led to a surge of interest in their educational applications. In this paper we briefly review the…

  10. 3D scene modeling from multiple range views

    NASA Astrophysics Data System (ADS)

    Sequeira, Vitor; Goncalves, Joao G. M.; Ribeiro, M. Isabel

    1995-09-01

    This paper presents a new 3D scene analysis system that automatically reconstructs the 3D geometric model of real-world scenes from multiple range images acquired by a laser range finder on board of a mobile robot. The reconstruction is achieved through an integrated procedure including range data acquisition, geometrical feature extraction, registration, and integration of multiple views. Different descriptions of the final 3D scene model are obtained: a polygonal triangular mesh, a surface description in terms of planar and biquadratics surfaces, and a 3D boundary representation. Relevant experimental results from the complete 3D scene modeling are presented. Direct applications of this technique include 3D reconstruction and/or update of architectual or industrial plans into a CAD model, design verification of buildings, navigation of autonomous robots, and input to virtual reality systems.

  11. 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…

  12. Virtual reality 3D headset based on DMD light modulators

    NASA Astrophysics Data System (ADS)

    Bernacki, Bruce E.; Evans, Allan; Tang, Edward

    2014-06-01

    We present the design of an immersion-type 3D headset suitable for virtual reality applications based upon digital micromirror devices (DMD). Current methods for presenting information for virtual reality are focused on either polarizationbased modulators such as liquid crystal on silicon (LCoS) devices, or miniature LCD or LED displays often using lenses to place the image at infinity. LCoS modulators are an area of active research and development, and reduce the amount of viewing light by 50% due to the use of polarization. Viewable LCD or LED screens may suffer low resolution, cause eye fatigue, and exhibit a "screen door" or pixelation effect due to the low pixel fill factor. Our approach leverages a mature technology based on silicon micro mirrors delivering 720p resolution displays in a small form-factor with high fill factor. Supporting chip sets allow rapid integration of these devices into wearable displays with high-definition resolution and low power consumption, and many of the design methods developed for DMD projector applications can be adapted to display use. Potential applications include night driving with natural depth perception, piloting of UAVs, fusion of multiple sensors for pilots, training, vision diagnostics and consumer gaming. Our design concept is described in which light from the DMD is imaged to infinity and the user's own eye lens forms a real image on the user's retina resulting in a virtual retinal display.

  13. Sensorized Garment Augmented 3D Pervasive Virtual Reality System

    NASA Astrophysics Data System (ADS)

    Gulrez, Tauseef; Tognetti, Alessandro; de Rossi, Danilo

    Virtual reality (VR) technology has matured to a point where humans can navigate in virtual scenes; however, providing them with a comfortable fully immersive role in VR remains a challenge. Currently available sensing solutions do not provide ease of deployment, particularly in the seated position due to sensor placement restrictions over the body, and optic-sensing requires a restricted indoor environment to track body movements. Here we present a 52-sensor laden garment interfaced with VR, which offers both portability and unencumbered user movement in a VR environment. This chapter addresses the systems engineering aspects of our pervasive computing solution of the interactive sensorized 3D VR and presents the initial results and future research directions. Participants navigated in a virtual art gallery using natural body movements that were detected by their wearable sensor shirt and then mapped the signals to electrical control signals responsible for VR scene navigation. The initial results are positive, and offer many opportunities for use in computationally intelligentman-machine multimedia control.

  14. Second Life, a 3-D Animated Virtual World: An Alternative Platform for (Art) Education

    ERIC Educational Resources Information Center

    Han, Hsiao-Cheng

    2011-01-01

    3-D animated virtual worlds are no longer only for gaming. With the advance of technology, animated virtual worlds not only are found on every computer, but also connect users with the internet. Today, virtual worlds are created not only by companies, but also through the collaboration of users. Online 3-D animated virtual worlds provide a new…

  15. Approach to Constructing 3d Virtual Scene of Irrigation Area Using Multi-Source Data

    NASA Astrophysics Data System (ADS)

    Cheng, S.; Dou, M.; Wang, J.; Zhang, S.; Chen, X.

    2015-10-01

    For an irrigation area that is often complicated by various 3D artificial ground features and natural environment, disadvantages of traditional 2D GIS in spatial data representation, management, query, analysis and visualization is becoming more and more evident. Building a more realistic 3D virtual scene is thus especially urgent for irrigation area managers and decision makers, so that they can carry out various irrigational operations lively and intuitively. Based on previous researchers' achievements, a simple, practical and cost-effective approach was proposed in this study, by adopting3D geographic information system (3D GIS), remote sensing (RS) technology. Based on multi-source data such as Google Earth (GE) high-resolution remote sensing image, ASTER G-DEM, hydrological facility maps and so on, 3D terrain model and ground feature models were created interactively. Both of the models were then rendered with texture data and integrated under ArcGIS platform. A vivid, realistic 3D virtual scene of irrigation area that has a good visual effect and possesses primary GIS functions about data query and analysis was constructed.Yet, there is still a long way to go for establishing a true 3D GIS for the irrigation are: issues of this study were deeply discussed and future research direction was pointed out in the end of the paper.

  16. 3-D Virtual and Physical Reconstruction of Bendego Iron

    NASA Astrophysics Data System (ADS)

    Belmonte, S. L. R.; Zucolotto, M. E.; Fontes, R. C.; dos Santos, J. R. L.

    2012-09-01

    The use of 3D laser scanning to meteoritic to preserve the original shape of the meteorites before cutting and the facility of saved the datas in STL format (stereolithography) to print three-dimensional physical models and generate a digital replica.

  17. The Esri 3D city information model

    NASA Astrophysics Data System (ADS)

    Reitz, T.; Schubiger-Banz, S.

    2014-02-01

    With residential and commercial space becoming increasingly scarce, cities are going vertical. Managing the urban environments in 3D is an increasingly important and complex undertaking. To help solving this problem, Esri has released the ArcGIS for 3D Cities solution. The ArcGIS for 3D Cities solution provides the information model, tools and apps for creating, analyzing and maintaining a 3D city using the ArcGIS platform. This paper presents an overview of the 3D City Information Model and some sample use cases.

  18. 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" (http://www.le.ac.uk/moose)…

  19. 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…

  20. 3D scanning modeling method application in ancient city reconstruction

    NASA Astrophysics Data System (ADS)

    Ren, Pu; Zhou, Mingquan; Du, Guoguang; Shui, Wuyang; Zhou, Pengbo

    2015-07-01

    With the development of optical engineering technology, the precision of 3D scanning equipment becomes higher, and its role in 3D modeling is getting more distinctive. This paper proposed a 3D scanning modeling method that has been successfully applied in Chinese ancient city reconstruction. On one hand, for the existing architectures, an improved algorithm based on multiple scanning is adopted. Firstly, two pieces of scanning data were rough rigid registered using spherical displacers and vertex clustering method. Secondly, a global weighted ICP (iterative closest points) method is used to achieve a fine rigid registration. On the other hand, for the buildings which have already disappeared, an exemplar-driven algorithm for rapid modeling was proposed. Based on the 3D scanning technology and the historical data, a system approach was proposed for 3D modeling and virtual display of ancient city.

  1. Digital Geology from field to 3D modelling and Google Earth virtual environment: methods and goals from the Furlo Gorge (Northern Apennines - Italy)

    NASA Astrophysics Data System (ADS)

    De Donatis, Mauro; Susini, Sara

    2014-05-01

    A new map of the Furlo Gorge was surveyed and elaborated in a digital way. In every step of work we used digital tools as mobile GIS and 3D modelling software. Phase 1st Starting in the lab, planning the field project development, base cartography, forms and data base were designed in the way we thought was the best for collecting and store data in order of producing a digital n­-dimensional map. Bedding attitudes, outcrops sketches and description, stratigraphic logs, structural features and other informations were collected and organised in a structured database using rugged tablet PC, GPS receiver, digital cameras and later also an Android smartphone with some survey apps in-­house developed. A new mobile GIS (BeeGIS) was developed starting from an open source GIS (uDig): a number of tools like GPS connection, pen drawing annotations, geonotes, fieldbook, photo synchronization and geotagging were originally designed. Phase 2nd After some month of digital field work, all the informations were elaborated for drawing a geologic map in GIS environment. For that we use both commercial (ArcGIS) and open source (gvSig, QGIS, uDig) without big technical problems. Phase 3rd When we get to the step of building a 3D model (using 3DMove), passing trough the assisted drawing of cross-­sections (2DMove), we discovered a number of problems in the interpretation of geological structures (thrusts, normal faults) and more in the interpretation of stratigraphic thickness and boundaries and their relationships with topography. Phase 4th Before an "on­-armchair" redrawing of map, we decide to go back to the field and check directly what was wrong. Two main vantages came from this: (1) the mistakes we found could be reinterpreted and corrected directly in the field having all digital tools we need; (2) previous interpretations could be stored in GIS layers keeping memory of the previous work (also mistakes). Phase 5th A 3D model built with 3D Move is already almost self

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

    NASA Astrophysics Data System (ADS)

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

    2016-03-01

    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.

  3. 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.

  4. Participatory Gis: Experimentations for a 3d Social Virtual Globe

    NASA Astrophysics Data System (ADS)

    Brovelli, M. A.; Minghini, M.; Zamboni, G.

    2013-08-01

    The dawn of GeoWeb 2.0, the geographic extension of Web 2.0, has opened new possibilities in terms of online dissemination and sharing of geospatial contents, thus laying the foundations for a fruitful development of Participatory GIS (PGIS). The purpose of the study is to investigate the extension of PGIS applications, which are quite mature in the traditional bi-dimensional framework, up to the third dimension. More in detail, the system should couple a powerful 3D visualization with an increase of public participation by means of a tool allowing data collecting from mobile devices (e.g. smartphones and tablets). The PGIS application, built using the open source NASA World Wind virtual globe, is focussed on the cultural and tourism heritage of Como city, located in Northern Italy. An authentication mechanism was implemented, which allows users to create and manage customized projects through cartographic mash-ups of Web Map Service (WMS) layers. Saved projects populate a catalogue which is available to the entire community. Together with historical maps and the current cartography of the city, the system is also able to manage geo-tagged multimedia data, which come from user field-surveys performed through mobile devices and report POIs (Points Of Interest). Each logged user can then contribute to POIs characterization by adding textual and multimedia information (e.g. images, audios and videos) directly on the globe. All in all, the resulting application allows users to create and share contributions as it usually happens on social platforms, additionally providing a realistic 3D representation enhancing the expressive power of data.

  5. Presence Pedagogy: Teaching and Learning in a 3D Virtual Immersive World

    ERIC Educational Resources Information Center

    Bronack, Stephen; Sanders, Robert; Cheney, Amelia; Riedl, Richard; Tashner, John; Matzen, Nita

    2008-01-01

    As the use of 3D immersive virtual worlds in higher education expands, it is important to examine which pedagogical approaches are most likely to bring about success. AET Zone, a 3D immersive virtual world in use for more than seven years, is one embodiment of pedagogical innovation that capitalizes on what virtual worlds have to offer to social…

  6. Accuracy of 3D Virtual Planning of Corrective Osteotomies of the Distal Radius.

    PubMed

    Stockmans, Filip; Dezillie, Marleen; Vanhaecke, Jeroen

    2013-11-01

    Corrective osteotomies of the distal radius for symptomatic malunion are time-tested procedures that rely on accurate corrections. Patients with combined intra- and extra-articular malunions present a challenging deformity. Virtual planning and patient-specific instruments (PSIs) to transfer the planning into the operating room have been used both to simplify the surgery and to make it more accurate. This report focuses on the clinically achieved accuracy in four patients treated between 2008 and 2012 with virtual planning and PSIs for a combined intra- and extraarticular malunion of the distal radius. The accuracy of the correction is quantified by comparing the virtual three-dimensional (3D) planning model with the postoperative 3D bone model. For the extraarticular malunion the 3D volar tilt, 3D radial inclination and 3D ulnar variance are measured. The volar tilt is undercorrected in all cases with an average of -6 ± 6°. The average difference between the postoperative and planned 3D radial inclination was -1 ± 5°. The average difference between the postoperative and planned 3D ulnar variances is 0 ± 1 mm. For the evaluation of the intraarticular malunion, both the arc method of measurement and distance map measurement are used. The average postoperative maximum gap is 2.1 ± 0.9 mm. The average maximum postoperative step-off is 1.3 ± 0.4 mm. The average distance between the postoperative and planned articular surfaces is 1.1 ± 0.6 mm as determined in the distance map measurement. There is a tendency to achieve higher accuracy as experience builds up, both on the surgeon's side and on the design engineering side. We believe this technology holds the potential to achieve consistent accuracy of very complex corrections. PMID:24436834

  7. Accuracy of 3D Virtual Planning of Corrective Osteotomies of the Distal Radius

    PubMed Central

    Stockmans, Filip; Dezillie, Marleen; Vanhaecke, Jeroen

    2013-01-01

    Corrective osteotomies of the distal radius for symptomatic malunion are time-tested procedures that rely on accurate corrections. Patients with combined intra- and extra-articular malunions present a challenging deformity. Virtual planning and patient-specific instruments (PSIs) to transfer the planning into the operating room have been used both to simplify the surgery and to make it more accurate. This report focuses on the clinically achieved accuracy in four patients treated between 2008 and 2012 with virtual planning and PSIs for a combined intra- and extraarticular malunion of the distal radius. The accuracy of the correction is quantified by comparing the virtual three-dimensional (3D) planning model with the postoperative 3D bone model. For the extraarticular malunion the 3D volar tilt, 3D radial inclination and 3D ulnar variance are measured. The volar tilt is undercorrected in all cases with an average of –6 ± 6°. The average difference between the postoperative and planned 3D radial inclination was –1 ± 5°. The average difference between the postoperative and planned 3D ulnar variances is 0 ± 1 mm. For the evaluation of the intraarticular malunion, both the arc method of measurement and distance map measurement are used. The average postoperative maximum gap is 2.1 ± 0.9 mm. The average maximum postoperative step-off is 1.3 ± 0.4 mm. The average distance between the postoperative and planned articular surfaces is 1.1 ± 0.6 mm as determined in the distance map measurement. There is a tendency to achieve higher accuracy as experience builds up, both on the surgeon's side and on the design engineering side. We believe this technology holds the potential to achieve consistent accuracy of very complex corrections. PMID:24436834

  8. BEAMS3D Neutral Beam Injection Model

    SciTech Connect

    Lazerson, Samuel

    2014-04-14

    With the advent of applied 3D fi elds in Tokamaks and modern high performance stellarators, a need has arisen to address non-axisymmetric effects on neutral beam heating and fueling. We report on the development of a fully 3D neutral beam injection (NBI) model, BEAMS3D, which addresses this need by coupling 3D equilibria to a guiding center code capable of modeling neutral and charged particle trajectories across the separatrix and into the plasma core. Ionization, neutralization, charge-exchange, viscous velocity reduction, and pitch angle scattering are modeled with the ADAS atomic physics database [1]. Benchmark calculations are presented to validate the collisionless particle orbits, neutral beam injection model, frictional drag, and pitch angle scattering effects. A calculation of neutral beam heating in the NCSX device is performed, highlighting the capability of the code to handle 3D magnetic fields.

  9. Modeling Cellular Processes in 3-D

    PubMed Central

    Mogilner, Alex; Odde, David

    2011-01-01

    Summary Recent advances in photonic imaging and fluorescent protein technology offer unprecedented views of molecular space-time dynamics in living cells. At the same time, advances in computing hardware and software enable modeling of ever more complex systems, from global climate to cell division. As modeling and experiment become more closely integrated, we must address the issue of modeling cellular processes in 3-D. Here, we highlight recent advances related to 3-D modeling in cell biology. While some processes require full 3-D analysis, we suggest that others are more naturally described in 2-D or 1-D. Keeping the dimensionality as low as possible reduces computational time and makes models more intuitively comprehensible; however, the ability to test full 3-D models will build greater confidence in models generally and remains an important emerging area of cell biological modeling. PMID:22036197

  10. Image based 3D city modeling : Comparative study

    NASA Astrophysics Data System (ADS)

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

    2014-06-01

    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 rapidly for various engineering and non-engineering applications. Generally four main image based approaches were used for virtual 3D city models generation. In first approach, researchers were used Sketch based modeling, second method is Procedural grammar based modeling, third approach is Close range photogrammetry based modeling and fourth approach is mainly based on Computer Vision techniques. SketchUp, CityEngine, Photomodeler and Agisoft Photoscan are the main softwares to represent these approaches respectively. These softwares have different approaches & methods suitable for image based 3D city modeling. Literature study shows that till date, there is no complete such type of comparative study available to create complete 3D city model by using images. This paper gives a comparative assessment of these four image based 3D modeling approaches. This comparative study is mainly based on data acquisition methods, data processing techniques and output 3D model products. For this research work, study area is the campus of civil engineering department, Indian Institute of Technology, Roorkee (India). This 3D campus acts as a prototype for city. This study also explains various governing parameters, factors and work experiences. This research work also gives a brief introduction, strengths and weakness of these four image based techniques. Some personal comment is also given as what can do or what can't do from these softwares. At the last, this study shows; it concluded that, each and every software has some advantages and limitations. Choice of software depends on user requirements of 3D project. For normal visualization project, SketchUp software is a good option. For 3D documentation record, Photomodeler gives good result. For Large city

  11. Radiosity diffusion model in 3D

    NASA Astrophysics Data System (ADS)

    Riley, Jason D.; Arridge, Simon R.; Chrysanthou, Yiorgos; Dehghani, Hamid; Hillman, Elizabeth M. C.; Schweiger, Martin

    2001-11-01

    We present the Radiosity-Diffusion model in three dimensions(3D), as an extension to previous work in 2D. It is a method for handling non-scattering spaces in optically participating media. We present the extension of the model to 3D including an extension to the model to cope with increased complexity of the 3D domain. We show that in 3D more careful consideration must be given to the issues of meshing and visibility to model the transport of light within reasonable computational bounds. We demonstrate the model to be comparable to Monte-Carlo simulations for selected geometries, and show preliminary results of comparisons to measured time-resolved data acquired on resin phantoms.

  12. 3D model reconstruction of underground goaf

    NASA Astrophysics Data System (ADS)

    Fang, Yuanmin; Zuo, Xiaoqing; Jin, Baoxuan

    2005-10-01

    Constructing 3D model of underground goaf, we can control the process of mining better and arrange mining work reasonably. However, the shape of goaf and the laneway among goafs are very irregular, which produce great difficulties in data-acquiring and 3D model reconstruction. In this paper, we research on the method of data-acquiring and 3D model construction of underground goaf, building topological relation among goafs. The main contents are as follows: a) The paper proposed an efficient encoding rule employed to structure the field measurement data. b) A 3D model construction method of goaf is put forward, which by means of combining several TIN (triangulated irregular network) pieces, and an efficient automatic processing algorithm of boundary of TIN is proposed. c) Topological relation of goaf models is established. TIN object is the basic modeling element of goaf 3D model, and the topological relation among goaf is created and maintained by building the topological relation among TIN objects. Based on this, various 3D spatial analysis functions can be performed including transect and volume calculation of goaf. A prototype is developed, which can realized the model and algorithm proposed in this paper.

  13. 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…

  14. 3D Visualization of Cultural Heritage Artefacts with Virtual Reality devices

    NASA Astrophysics Data System (ADS)

    Gonizzi Barsanti, S.; Caruso, G.; Micoli, L. L.; Covarrubias Rodriguez, M.; Guidi, G.

    2015-08-01

    Although 3D models are useful to preserve the information about historical artefacts, the potential of these digital contents are not fully accomplished until they are not used to interactively communicate their significance to non-specialists. Starting from this consideration, a new way to provide museum visitors with more information was investigated. The research is aimed at valorising and making more accessible the Egyptian funeral objects exhibited in the Sforza Castle in Milan. The results of the research will be used for the renewal of the current exhibition, at the Archaeological Museum in Milan, by making it more attractive. A 3D virtual interactive scenario regarding the "path of the dead", an important ritual in ancient Egypt, was realized to augment the experience and the comprehension of the public through interactivity. Four important artefacts were considered for this scope: two ushabty, a wooden sarcophagus and a heart scarab. The scenario was realized by integrating low-cost Virtual Reality technologies, as the Oculus Rift DK2 and the Leap Motion controller, and implementing a specific software by using Unity. The 3D models were implemented by adding responsive points of interest in relation to important symbols or features of the artefact. This allows highlighting single parts of the artefact in order to better identify the hieroglyphs and provide their translation. The paper describes the process for optimizing the 3D models, the implementation of the interactive scenario and the results of some test that have been carried out in the lab.

  15. Virtual Spring-Based 3D Multi-Agent Group Coordination

    NASA Astrophysics Data System (ADS)

    Daneshvar, Roozbeh; Shih, Liwen

    As future personal vehicles start enjoying the ability to fly, tackling safe transportation coordination can be a tremendous task, far beyond the current challenge on radar screen monitoring of the already saturated air traffic control. Our focus is on the distributed safe-distance coordination among a group of autonomous flying vehicle agents, where each follows its own current straight-line direction in a 3D space with variable speeds. A virtual spring-based model is proposed for the group coordination. Within a specified neighborhood radius, each vehicle forms a virtual connection with each neighbor vehicle by a virtual spring. As the vehicle changes its position, speed and altitude, the total resultant forces on each virtual spring try to maintain zero by moving to the mechanical equilibrium point. The agents then add the simple total virtual spring constraints to their movements to determine their next positions individually. Together, the multi-agent vehicles reach a group behavior, where each of them keeps a minimal safe-distance with others. A new safe behavior thus arises in the group level. With the proposed virtual spring coordination model, the vehicles need no direct communication with each other, require only minimum local processing resources, and the control is completely distributed. New behaviors can now be formulated and studied based on the proposed model, e.g., how a fast driving vehicle can find its way though the crowd by avoiding the other vehicles effortlessly1.

  16. 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…

  17. 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…

  18. 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…

  19. Metrological validation for 3D modeling of dental plaster casts.

    PubMed

    Brusco, Nicola; Andreetto, Marco; Lucchese, Luca; Carmignato, Simone; Cortelazzo, Guido M

    2007-11-01

    The contribution of this paper is twofold: (1) it presents an automatic 3D modeling technique and (2) it advances a procedure for its metrological evaluation in the context of a medical application, the 3D modeling of dental plaster casts. The motivation for this work is the creation of a "virtual gypsotheque" where cumbersome dental plaster casts can be replaced by numerical 3D models, thereby alleviating storage and access problems and allowing dentists and orthodontists the use of novel and unprecedented software tools for their medical evaluations. Modeling free-form surfaces of anatomical interest is an intriguing mixture of open issues concerning 3D modeling, geometrical metrology, and medicine. Of general interest is both the fact that a widespread use of 3D modeling in non-engineering applications requires automatic procedures of the kind presented in this work and the adopted validation paradigm for free-form surfaces, rather useful for practical purposes. In this latter respect, the metrological analysis we advance is the first seminal attempt in the field of 3D modeling and can be readily extended to contexts other than the medical one discussed in this paper. PMID:17126062

  20. 3D structure of nucleon with virtuality distributions

    NASA Astrophysics Data System (ADS)

    Radyushkin, Anatoly

    2014-09-01

    We describe a new approach to transverse momentum dependence in hard processes. Our starting point is coordinate representation for matrix elements of operators (in the simplest case, bilocal O (0 , z)) describing a hadron with momentum p. Treated as functions of (pz) and z2, they are parametrized through parton virtuality distribution (PVD) Φ (x , σ) , with x being Fourier-conjugate to (pz) and σ Laplace-conjugate to z2. For intervals with z+ = 0 , we introduce the transverse momentum distribution (TMD) f (x ,k⊥) , and write it in terms of PVD Φ (x , σ) . The results of covariant calculations, written in terms of Φ (x , σ) are converted into expressions involving f (x ,k⊥) . We propose models for soft PVDs/TMDs,and describe how one can generate high-k⊥ tails of TMDs from primordial soft distributions. We describe a new approach to transverse momentum dependence in hard processes. Our starting point is coordinate representation for matrix elements of operators (in the simplest case, bilocal O (0 , z)) describing a hadron with momentum p. Treated as functions of (pz) and z2, they are parametrized through parton virtuality distribution (PVD) Φ (x , σ) , with x being Fourier-conjugate to (pz) and σ Laplace-conjugate to z2. For intervals with z+ = 0 , we introduce the transverse momentum distribution (TMD) f (x ,k⊥) , and write it in terms of PVD Φ (x , σ) . The results of covariant calculations, written in terms of Φ (x , σ) are converted into expressions involving f (x ,k⊥) . We propose models for soft PVDs/TMDs,and describe how one can generate high-k⊥ tails of TMDs from primordial soft distributions. Supported by Jefferson Science Associates, LLC under U.S. DOE Contract #DE-AC05-06OR23177 and by U.S. DOE Grant #DE-FG02-97ER41028.

  1. 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.

  2. Parallel Optimization of 3D Cardiac Electrophysiological Model Using GPU

    PubMed Central

    Xia, Yong; Wang, Kuanquan; Zhang, Henggui

    2015-01-01

    Large-scale 3D virtual heart model simulations are highly demanding in computational resources. This imposes a big challenge to the traditional computation resources based on CPU environment, which already cannot meet the requirement of the whole computation demands or are not easily available due to expensive costs. GPU as a parallel computing environment therefore provides an alternative to solve the large-scale computational problems of whole heart modeling. In this study, using a 3D sheep atrial model as a test bed, we developed a GPU-based simulation algorithm to simulate the conduction of electrical excitation waves in the 3D atria. In the GPU algorithm, a multicellular tissue model was split into two components: one is the single cell model (ordinary differential equation) and the other is the diffusion term of the monodomain model (partial differential equation). Such a decoupling enabled realization of the GPU parallel algorithm. Furthermore, several optimization strategies were proposed based on the features of the virtual heart model, which enabled a 200-fold speedup as compared to a CPU implementation. In conclusion, an optimized GPU algorithm has been developed that provides an economic and powerful platform for 3D whole heart simulations. PMID:26581957

  3. 3D Modeling Engine Representation Summary Report

    SciTech Connect

    Steven Prescott; Ramprasad Sampath; Curtis Smith; Timothy Yang

    2014-09-01

    Computers have been used for 3D modeling and simulation, but only recently have computational resources been able to give realistic results in a reasonable time frame for large complex models. This summary report addressed the methods, techniques, and resources used to develop a 3D modeling engine to represent risk analysis simulation for advanced small modular reactor structures and components. The simulations done for this evaluation were focused on external events, specifically tsunami floods, for a hypothetical nuclear power facility on a coastline.

  4. An Interactive Virtual 3D Tool for Scientific Exploration of Planetary Surfaces

    NASA Astrophysics Data System (ADS)

    Traxler, Christoph; Hesina, Gerd; Gupta, Sanjeev; Paar, Gerhard

    2014-05-01

    In this paper we present an interactive 3D visualization tool for scientific analysis and planning of planetary missions. At the moment scientists have to look at individual camera images separately. There is no tool to combine them in three dimensions and look at them seamlessly as a geologist would do (by walking backwards and forwards resulting in different scales). For this reason a virtual 3D reconstruction of the terrain that can be interactively explored is necessary. Such a reconstruction has to consider multiple scales ranging from orbital image data to close-up surface image data from rover cameras. The 3D viewer allows seamless zooming between these various scales, giving scientists the possibility to relate small surface features (e.g. rock outcrops) to larger geological contexts. For a reliable geologic assessment a realistic surface rendering is important. Therefore the material properties of the rock surfaces will be considered for real-time rendering. This is achieved by an appropriate Bidirectional Reflectance Distribution Function (BRDF) estimated from the image data. The BRDF is implemented to run on the Graphical Processing Unit (GPU) to enable realistic real-time rendering, which allows a naturalistic perception for scientific analysis. Another important aspect for realism is the consideration of natural lighting conditions, which means skylight to illuminate the reconstructed scene. In our case we provide skylights from Mars and Earth, which allows switching between these two modes of illumination. This gives geologists the opportunity to perceive rock outcrops from Mars as they would appear on Earth facilitating scientific assessment. Besides viewing the virtual reconstruction on multiple scales, scientists can also perform various measurements, i.e. geo-coordinates of a selected point or distance between two surface points. Rover or other models can be placed into the scene and snapped onto certain location of the terrain. These are

  5. Contextual EFL Learning in a 3D Virtual Environment

    ERIC Educational Resources Information Center

    Lan, Yu-Ju

    2015-01-01

    The purposes of the current study are to develop virtually immersive EFL learning contexts for EFL learners in Taiwan to pre- and review English materials beyond the regular English class schedule. A 2-iteration action research lasting for one semester was conducted to evaluate the effects of virtual contexts on learners' EFL learning. 132…

  6. 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…

  7. Dynamic WIFI-Based Indoor Positioning in 3D Virtual World

    NASA Astrophysics Data System (ADS)

    Chan, S.; Sohn, G.; Wang, L.; Lee, W.

    2013-11-01

    A web-based system based on the 3DTown project was proposed using Google Earth plug-in that brings information from indoor positioning devices and real-time sensors into an integrated 3D indoor and outdoor virtual world to visualize the dynamics of urban life within the 3D context of a city. We addressed limitation of the 3DTown project with particular emphasis on video surveillance camera used for indoor tracking purposes. The proposed solution was to utilize wireless local area network (WLAN) WiFi as a replacement technology for localizing objects of interest due to the wide spread availability and large coverage area of WiFi in indoor building spaces. Indoor positioning was performed using WiFi without modifying existing building infrastructure or introducing additional access points (AP)s. A hybrid probabilistic approach was used for indoor positioning based on previously recorded WiFi fingerprint database in the Petrie Science and Engineering building at York University. In addition, we have developed a 3D building modeling module that allows for efficient reconstruction of outdoor building models to be integrated with indoor building models; a sensor module for receiving, distributing, and visualizing real-time sensor data; and a web-based visualization module for users to explore the dynamic urban life in a virtual world. In order to solve the problems in the implementation of the proposed system, we introduce approaches for integration of indoor building models with indoor positioning data, as well as real-time sensor information and visualization on the web-based system. In this paper we report the preliminary results of our prototype system, demonstrating the system's capability for implementing a dynamic 3D indoor and outdoor virtual world that is composed of discrete modules connected through pre-determined communication protocols.

  8. BEAMS3D Neutral Beam Injection Model

    NASA Astrophysics Data System (ADS)

    McMillan, Matthew; Lazerson, Samuel A.

    2014-09-01

    With the advent of applied 3D fields in Tokamaks and modern high performance stellarators, a need has arisen to address non-axisymmetric effects on neutral beam heating and fueling. We report on the development of a fully 3D neutral beam injection (NBI) model, BEAMS3D, which addresses this need by coupling 3D equilibria to a guiding center code capable of modeling neutral and charged particle trajectories across the separatrix and into the plasma core. Ionization, neutralization, charge-exchange, viscous slowing down, and pitch angle scattering are modeled with the ADAS atomic physics database. Elementary benchmark calculations are presented to verify the collisionless particle orbits, NBI model, frictional drag, and pitch angle scattering effects. A calculation of neutral beam heating in the NCSX device is performed, highlighting the capability of the code to handle 3D magnetic fields. Notice: this manuscript has been authored by Princeton University under Contract Number DE-AC02-09CH11466 with the US Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes.

  9. Virtual 3D bladder reconstruction for augmented medical records from white light cystoscopy (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Lurie, Kristen L.; Zlatev, Dimitar V.; Angst, Roland; Liao, Joseph C.; Ellerbee, Audrey K.

    2016-02-01

    Bladder cancer has a high recurrence rate that necessitates lifelong surveillance to detect mucosal lesions. Examination with white light cystoscopy (WLC), the standard of care, is inherently subjective and data storage limited to clinical notes, diagrams, and still images. A visual history of the bladder wall can enhance clinical and surgical management. To address this clinical need, we developed a tool to transform in vivo WLC videos into virtual 3-dimensional (3D) bladder models using advanced computer vision techniques. WLC videos from rigid cystoscopies (1280 x 720 pixels) were recorded at 30 Hz followed by immediate camera calibration to control for image distortions. Video data were fed into an automated structure-from-motion algorithm that generated a 3D point cloud followed by a 3D mesh to approximate the bladder surface. The highest quality cystoscopic images were projected onto the approximated bladder surface to generate a virtual 3D bladder reconstruction. In intraoperative WLC videos from 36 patients undergoing transurethral resection of suspected bladder tumors, optimal reconstruction was achieved from frames depicting well-focused vasculature, when the bladder was maintained at constant volume with minimal debris, and when regions of the bladder wall were imaged multiple times. A significant innovation of this work is the ability to perform the reconstruction using video from a clinical procedure collected with standard equipment, thereby facilitating rapid clinical translation, application to other forms of endoscopy and new opportunities for longitudinal studies of cancer recurrence.

  10. Solar abundances and 3D model atmospheres

    NASA Astrophysics Data System (ADS)

    Ludwig, Hans-Günter; Caffau, Elisabetta; Steffen, Matthias; Bonifacio, Piercarlo; Freytag, Bernd; Cayrel, Roger

    2010-03-01

    We present solar photospheric abundances for 12 elements from optical and near-infrared spectroscopy. The abundance analysis was conducted employing 3D hydrodynamical (CO5BOLD) as well as standard 1D hydrostatic model atmospheres. We compare our results to others with emphasis on discrepancies and still lingering problems, in particular exemplified by the pivotal abundance of oxygen. We argue that the thermal structure of the lower solar photosphere is very well represented by our 3D model. We obtain an excellent match of the observed center-to-limb variation of the line-blanketed continuum intensity, also at wavelengths shortward of the Balmer jump.

  11. Evaluation of Home Delivery of Lectures Utilizing 3D Virtual Space Infrastructure

    ERIC Educational Resources Information Center

    Nishide, Ryo; Shima, Ryoichi; Araie, Hiromu; Ueshima, Shinichi

    2007-01-01

    Evaluation experiments have been essential in exploring home delivery of lectures for which users can experience campus lifestyle and distant learning through 3D virtual space. This paper discusses the necessity of virtual space for distant learners by examining the effects of virtual space. The authors have pursued the possibility of…

  12. 3-D Teaching Models for All

    ERIC Educational Resources Information Center

    Bradley, Joan; Farland-Smith, Donna

    2010-01-01

    Allowing a student to "see" through touch what other students see through a microscope can be a challenging task. Therefore, author Joan Bradley created three-dimensional (3-D) models with one student's visual impairment in mind. They are meant to benefit all students and can be used to teach common high school biology topics, including the…

  13. M3D (Media 3D): a new programming language for web-based virtual reality in E-Learning and Edutainment

    NASA Astrophysics Data System (ADS)

    Chakaveh, Sepideh; Skaley, Detlef; Laine, Patricia; Haeger, Ralf; Maad, Soha

    2003-01-01

    Today, interactive multimedia educational systems are well established, as they prove useful instruments to enhance one's learning capabilities. Hitherto, the main difficulty with almost all E-Learning systems was latent in the rich media implementation techniques. This meant that each and every system should be created individually as reapplying the media, be it only a part, or the whole content was not directly possible, as everything must be applied mechanically i.e. by hand. Consequently making E-learning systems exceedingly expensive to generate, both in time and money terms. Media-3D or M3D is a new platform independent programming language, developed at the Fraunhofer Institute Media Communication to enable visualisation and simulation of E-Learning multimedia content. M3D is an XML-based language, which is capable of distinguishing between the3D models from that of the 3D scenes, as well as handling provisions for animations, within the programme. Here we give a technical account of M3D programming language and briefly describe two specific application scenarios where M3D is applied to create virtual reality E-Learning content for training of technical personnel.

  14. Debris Dispersion Model Using Java 3D

    NASA Technical Reports Server (NTRS)

    Thirumalainambi, Rajkumar; Bardina, Jorge

    2004-01-01

    This paper describes web based simulation of Shuttle launch operations and debris dispersion. Java 3D graphics provides geometric and visual content with suitable mathematical model and behaviors of Shuttle launch. Because the model is so heterogeneous and interrelated with various factors, 3D graphics combined with physical models provides mechanisms to understand the complexity of launch and range operations. The main focus in the modeling and simulation covers orbital dynamics and range safety. Range safety areas include destruct limit lines, telemetry and tracking and population risk near range. If there is an explosion of Shuttle during launch, debris dispersion is explained. The shuttle launch and range operations in this paper are discussed based on the operations from Kennedy Space Center, Florida, USA.

  15. 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. PMID:25098158

  16. Special Section: New Ways to Detect Colon Cancer 3-D virtual screening now being used

    MedlinePlus

    ... body) from the National Library of Medicine's Visible Human project (www.nlm.nih.gov). By 1996, Kaufman and his colleagues had patented a pioneering computer software system and techniques for 3-D virtual ...

  17. Elastic registration using 3D ChainMail: application to virtual colonoscopy

    NASA Astrophysics Data System (ADS)

    Castro-Pareja, Carlos R.; Daly, Barry; Shekhar, Raj

    2006-03-01

    We present an elastic registration algorithm based on local deformations modeled using cubic B-splines and controlled using 3D ChainMail. Our algorithm eliminates the appearance of folding artifacts and allows local rigidity and compressibility control independent of the image similarity metric being used. 3D ChainMail propagates large internal deformations between neighboring B-Spline control points, thereby preserving the topology of the transformed image without requiring the addition of penalty terms based on rigidity of the transformation field to the equation used to maximize image similarity. A novel application to virtual colonoscopy is presented where the algorithm is used to significantly improve cross-localization between colon locations in prone and supine CT images.

  18. Integrated Biogeomorphological Modeling Using Delft3D

    NASA Astrophysics Data System (ADS)

    Ye, Q.; Jagers, B.

    2011-12-01

    The skill of numerical morphological models has improved significantly from the early 2D uniform, total load sediment models (with steady state or infrequent wave updates) to recent 3D hydrodynamic models with multiple suspended and bed load sediment fractions and bed stratigraphy (online coupled with waves). Although there remain many open questions within this combined field of hydro- and morphodynamics, we observe an increasing need to include biological processes in the overall dynamics. In riverine and inter-tidal environments, there is often an important influence by riparian vegetation and macrobenthos. Over the past decade more and more researchers have started to extend the simulation environment with wrapper scripts and other quick code hacks to estimate their influence on morphological development in coastal, estuarine and riverine environments. Although one can in this way quickly analyze different approaches, these research tools have generally not been designed with reuse, performance and portability in mind. We have now implemented a reusable, flexible, and efficient two-way link between the Delft3D open source framework for hydrodynamics, waves and morphology, and the water quality and ecology modules. The same link will be used for 1D, 2D and 3D modeling on networks and both structured and unstructured grids. We will describe the concepts of the overall system, and illustrate it with some first results.

  19. Sensing and compressing 3-D models

    SciTech Connect

    Krumm, J.

    1998-02-01

    The goal of this research project was to create a passive and robust computer vision system for producing 3-D computer models of arbitrary scenes. Although the authors were unsuccessful in achieving the overall goal, several components of this research have shown significant potential. Of particular interest is the application of parametric eigenspace methods for planar pose measurement of partially occluded objects in gray-level images. The techniques presented provide a simple, accurate, and robust solution to the planar pose measurement problem. In addition, the representational efficiency of eigenspace methods used with gray-level features were successfully extended to binary features, which are less sensitive to illumination changes. The results of this research are presented in two papers that were written during the course of this project. The papers are included in sections 2 and 3. The first section of this report summarizes the 3-D modeling efforts.

  20. 3D modeling of optically challenging objects.

    PubMed

    Park, Johnny; Kak, Avinash

    2008-01-01

    We present a system for constructing 3D models of real-world objects with optically challenging surfaces. The system utilizes a new range imaging concept called multi-peak range imaging, which stores multiple candidates of range measurements for each point on the object surface. The multiple measurements include the erroneous range data caused by various surface properties that are not ideal for structured-light range sensing. False measurements generated by spurious reflections are eliminated by applying a series of constraint tests. The constraint tests based on local surface and local sensor visibility are applied first to individual range images. The constraint tests based on global consistency of coordinates and visibility are then applied to all range images acquired from different viewpoints. We show the effectiveness of our method by constructing 3D models of five different optically challenging objects. To evaluate the performance of the constraint tests and to examine the effects of the parameters used in the constraint tests, we acquired the ground truth data by painting those objects to suppress the surface-related properties that cause difficulties in range sensing. Experimental results indicate that our method significantly improves upon the traditional methods for constructing reliable 3D models of optically challenging objects. PMID:18192707

  1. Robust hashing for 3D models

    NASA Astrophysics Data System (ADS)

    Berchtold, Waldemar; Schäfer, Marcel; Rettig, Michael; Steinebach, Martin

    2014-02-01

    3D models and applications are of utmost interest in both science and industry. With the increment of their usage, their number and thereby the challenge to correctly identify them increases. Content identification is commonly done by cryptographic hashes. However, they fail as a solution in application scenarios such as computer aided design (CAD), scientific visualization or video games, because even the smallest alteration of the 3D model, e.g. conversion or compression operations, massively changes the cryptographic hash as well. Therefore, this work presents a robust hashing algorithm for 3D mesh data. The algorithm applies several different bit extraction methods. They are built to resist desired alterations of the model as well as malicious attacks intending to prevent correct allocation. The different bit extraction methods are tested against each other and, as far as possible, the hashing algorithm is compared to the state of the art. The parameters tested are robustness, security and runtime performance as well as False Acceptance Rate (FAR) and False Rejection Rate (FRR), also the probability calculation of hash collision is included. The introduced hashing algorithm is kept adaptive e.g. in hash length, to serve as a proper tool for all applications in practice.

  2. A Parameterizable Framework for Replicated Experiments in Virtual 3D Environments

    NASA Astrophysics Data System (ADS)

    Biella, Daniel; Luther, Wolfram

    This paper reports on a parameterizable 3D framework that provides 3D content developers with an initial spatial starting configuration, metaphorical connectors for accessing exhibits or interactive 3D learning objects or experiments, and other optional 3D extensions, such as a multimedia room, a gallery, username identification tools and an avatar selection room. The framework is implemented in X3D and uses a Web-based content management system. It has been successfully used for an interactive virtual museum for key historical experiments and in two additional interactive e-learning implementations: an African arts museum and a virtual science centre. It can be shown that, by reusing the framework, the production costs for the latter two implementations can be significantly reduced and content designers can focus on developing educational content instead of producing cost-intensive out-of-focus 3D objects.

  3. 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

  4. Anesthesiology training using 3D imaging and virtual reality

    NASA Astrophysics Data System (ADS)

    Blezek, Daniel J.; Robb, Richard A.; Camp, Jon J.; Nauss, Lee A.

    1996-04-01

    Current training for regional nerve block procedures by anesthesiology residents requires expert supervision and the use of cadavers; both of which are relatively expensive commodities in today's cost-conscious medical environment. We are developing methods to augment and eventually replace these training procedures with real-time and realistic computer visualizations and manipulations of the anatomical structures involved in anesthesiology procedures, such as nerve plexus injections (e.g., celiac blocks). The initial work is focused on visualizations: both static images and rotational renderings. From the initial results, a coherent paradigm for virtual patient and scene representation will be developed.

  5. Fallon FORGE 3D Geologic Model

    DOE Data Explorer

    Doug Blankenship

    2016-03-01

    An x,y,z scattered data file for the 3D geologic model of the Fallon FORGE site. Model created in Earthvision by Dynamic Graphic Inc. The model was constructed with a grid spacing of 100 m. Geologic surfaces were extrapolated from the input data using a minimum tension gridding algorithm. The data file is tabular data in a text file, with lithology data associated with X,Y,Z grid points. All the relevant information is in the file header (the spatial reference, the projection etc.) In addition all the fields in the data file are identified in the header.

  6. 3D Models of Symbiotic Binaries

    NASA Astrophysics Data System (ADS)

    Mohamed, S.; Booth, R.; Podsiadlowski, Ph.; Ramstedt, S.; Vlemmings, W.; Maercker, M.

    2015-12-01

    Symbiotic binaries consist of a cool, mass-losing giant and an accreting, compact companion. We present 3D Smoothed Particle Hydrodynamics (SPH) models of two such interacting binaries, RS Oph and Mira AB. RS Oph is also a recurrent nova system, thus we model multiple quiescent mass transfer-nova outburst cycles. The resulting circumstellar structures of both systems are highly complex with the formation of spirals, arcs, shells, equatorial and bipolar outflows. We compare the models to recent observations and discuss the implications of our results for related systems, e.g., bipolar nebulae and jets, chemically peculiar stars, and the progenitors of Type Ia supernovae.

  7. 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 research…

  8. 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…

  9. Virtual 3D interactive system with embedded multiwavelength optical sensor array and sequential devices

    NASA Astrophysics Data System (ADS)

    Wang, Guo-Zhen; Huang, Yi-Pai; Hu, Kuo-Jui

    2012-06-01

    We proposed a virtual 3D-touch system by bare finger, which can detect the 3-axis (x, y, z) information of finger. This system has multi-wavelength optical sensor array embedded on the backplane of TFT panel and sequentail devices on the border of TFT panel. We had developed reflecting mode which can be worked by bare finger for the 3D interaction. A 4-inch mobile 3D-LCD with this proposed system was successfully been demonstrated already.

  10. Inferential modeling of 3D chromatin structure

    PubMed Central

    Wang, Siyu; Xu, Jinbo; Zeng, Jianyang

    2015-01-01

    For eukaryotic cells, the biological processes involving regulatory DNA elements play an important role in cell cycle. Understanding 3D spatial arrangements of chromosomes and revealing long-range chromatin interactions are critical to decipher these biological processes. In recent years, chromosome conformation capture (3C) related techniques have been developed to measure the interaction frequencies between long-range genome loci, which have provided a great opportunity to decode the 3D organization of the genome. In this paper, we develop a new Bayesian framework to derive the 3D architecture of a chromosome from 3C-based data. By modeling each chromosome as a polymer chain, we define the conformational energy based on our current knowledge on polymer physics and use it as prior information in the Bayesian framework. We also propose an expectation-maximization (EM) based algorithm to estimate the unknown parameters of the Bayesian model and infer an ensemble of chromatin structures based on interaction frequency data. We have validated our Bayesian inference approach through cross-validation and verified the computed chromatin conformations using the geometric constraints derived from fluorescence in situ hybridization (FISH) experiments. We have further confirmed the inferred chromatin structures using the known genetic interactions derived from other studies in the literature. Our test results have indicated that our Bayesian framework can compute an accurate ensemble of 3D chromatin conformations that best interpret the distance constraints derived from 3C-based data and also agree with other sources of geometric constraints derived from experimental evidence in the previous studies. The source code of our approach can be found in https://github.com/wangsy11/InfMod3DGen. PMID:25690896

  11. A method of 3-D data information storage with virtual holography

    NASA Astrophysics Data System (ADS)

    Huang, Zhen; Liu, Guodong; Ren, Zhong; Zeng, Lüming

    2008-12-01

    In this paper, a new method of 3-D data cube based on virtual holographic storage is presented. Firstly, the data information is encoded in the form of 3-D data cube with a certain algorithm, in which the interval along coordinates between every data is d. Using the plane-scanning method, the 3-D cube can be described as a assembly of slices which are parallel planes along the coordinates at an interval of d. The dot on the slice represents a bit. The bright one means "1", while the dark one means "0". Secondly, a hologram of the 3-D cube is obtained by computer with virtual optics technology. All the information of a 3-D cube can be described by a 2-D hologram. At last, the hologram is inputted in the SLM, and recorded in the recording material by intersecting two coherent laser beams. When the 3-D data is exported, a reference light illuminates the hologram, and a CCD is used to get the object image which is a hologram of the 3-D data. Then the 3-D data is computed with virtual optical technology. Compared with 2-D data page storage, the 3-D data cube storage has outstanding performance in larger capacity of data storage and higher security of data.

  12. 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…

  13. The Virtual-casing Principle For 3D Toroidal Systems

    SciTech Connect

    Lazerson, Samuel A.

    2014-02-24

    The capability to calculate the magnetic field due to the plasma currents in a toroidally confined magnetic fusion equilibrium is of manifest relevance to equilibrium reconstruction and stellarator divertor design. Two methodologies arise for calculating such quantities. The first being a volume integral over the plasma current density for a given equilibrium. Such an integral is computationally expensive. The second is a surface integral over a surface current on the equilibrium boundary. This method is computationally desirable as the calculation does not grow as the radial resolution of the volume integral. This surface integral method has come to be known as the "virtual-casing principle". In this paper, a full derivation of this method is presented along with a discussion regarding its optimal application.

  14. Improving Semantic Updating Method on 3d City Models Using Hybrid Semantic-Geometric 3d Segmentation Technique

    NASA Astrophysics Data System (ADS)

    Sharkawi, K.-H.; Abdul-Rahman, A.

    2013-09-01

    Cities and urban areas entities such as building structures are becoming more complex as the modern human civilizations continue to evolve. The ability to plan and manage every territory especially the urban areas is very important to every government in the world. Planning and managing cities and urban areas based on printed maps and 2D data are getting insufficient and inefficient to cope with the complexity of the new developments in big cities. The emergence of 3D city models have boosted the efficiency in analysing and managing urban areas as the 3D data are proven to represent the real world object more accurately. It has since been adopted as the new trend in buildings and urban management and planning applications. Nowadays, many countries around the world have been generating virtual 3D representation of their major cities. The growing interest in improving the usability of 3D city models has resulted in the development of various tools for analysis based on the 3D city models. Today, 3D city models are generated for various purposes such as for tourism, location-based services, disaster management and urban planning. Meanwhile, modelling 3D objects are getting easier with the emergence of the user-friendly tools for 3D modelling available in the market. Generating 3D buildings with high accuracy also has become easier with the availability of airborne Lidar and terrestrial laser scanning equipments. The availability and accessibility to this technology makes it more sensible to analyse buildings in urban areas using 3D data as it accurately represent the real world objects. The Open Geospatial Consortium (OGC) has accepted CityGML specifications as one of the international standards for representing and exchanging spatial data, making it easier to visualize, store and manage 3D city models data efficiently. CityGML able to represents the semantics, geometry, topology and appearance of 3D city models in five well-defined Level-of-Details (LoD), namely LoD0

  15. The cranial nerve skywalk: A 3D tutorial of cranial nerves in a virtual platform.

    PubMed

    Richardson-Hatcher, April; Hazzard, Matthew; Ramirez-Yanez, German

    2014-01-01

    Visualization of the complex courses of the cranial nerves by students in the health-related professions is challenging through either diagrams in books or plastic models in the gross laboratory. Furthermore, dissection of the cranial nerves in the gross laboratory is an extremely meticulous task. Teaching and learning the cranial nerve pathways is difficult using two-dimensional (2D) illustrations alone. Three-dimensional (3D) models aid the teacher in describing intricate and complex anatomical structures and help students visualize them. The study of the cranial nerves can be supplemented with 3D, which permits the students to fully visualize their distribution within the craniofacial complex. This article describes the construction and usage of a virtual anatomy platform in Second Life™, which contains 3D models of the cranial nerves III, V, VII, and IX. The Cranial Nerve Skywalk features select cranial nerves and the associated autonomic pathways in an immersive online environment. This teaching supplement was introduced to groups of pre-healthcare professional students in gross anatomy courses at both institutions and student feedback is included. PMID:24678025

  16. Tracking people and cars using 3D modeling and CCTV.

    PubMed

    Edelman, Gerda; Bijhold, Jurrien

    2010-10-10

    The aim of this study was to find a method for the reconstruction of movements of people and cars using CCTV footage and a 3D model of the environment. A procedure is proposed, in which video streams are synchronized and displayed in a 3D model, by using virtual cameras. People and cars are represented by cylinders and boxes, which are moved in the 3D model, according to their movements as shown in the video streams. The procedure was developed and tested in an experimental setup with test persons who logged their GPS coordinates as a recording of the ground truth. Results showed that it is possible to implement this procedure and to reconstruct movements of people and cars from video recordings. The procedure was also applied to a forensic case. In this work we experienced that more situational awareness was created by the 3D model, which made it easier to track people on multiple video streams. Based on all experiences from the experimental set up and the case, recommendations are formulated for use in practice. PMID:20439141

  17. 3D Model of Surfactant Replacement Therapy

    NASA Astrophysics Data System (ADS)

    Grotberg, James; Tai, Cheng-Feng; Filoche, Marcel

    2015-11-01

    Surfactant Replacement Therapy (SRT) involves instillation of a liquid-surfactant mixture directly into the lung airway tree. Though successful in neonatal applications, its use in adults had early success followed by failure. We present the first mathematical model of 3D SRT where a liquid plug propagates through the tree from forced inspiration. In two separate modeling steps, the plug first deposits a coating film on the airway wall which subtracts from its volume, a ``coating cost''. Then the plug splits unevenly at the airway bifurcation due to gravity. The steps are repeated until a plug ruptures or reaches the tree endpoint alveoli/acinus. The model generates 3D images of the resulting acinar distribution and calculates two global indexes, efficiency and homogeneity. Simulating published literature, the earlier successful adult SRT studies show comparatively good index values, while the later failed studies do not. Those unsuccessful studies used smaller dose volumes with higher concentration mixtures, apparently assuming a well mixed compartment. The model shows that adult lungs are not well mixed in SRT due to the coating cost and gravity effects. Returning to the higher dose volume protocols could save many thousands of lives annually in the US. Supported by NIH Grants HL85156, HL84370 and Agence Nationale de la Recherche, ANR no. 2010-BLAN-1119-05.

  18. Creating Physical 3D Stereolithograph Models of Brain and Skull

    PubMed Central

    Kelley, Daniel J.; Farhoud, Mohammed; Meyerand, M. Elizabeth; Nelson, David L.; Ramirez, Lincoln F.; Dempsey, Robert J.; Wolf, Alan J.; Alexander, Andrew L.; Davidson, Richard J.

    2007-01-01

    The human brain and skull are three dimensional (3D) anatomical structures with complex surfaces. However, medical images are often two dimensional (2D) and provide incomplete visualization of structural morphology. To overcome this loss in dimension, we developed and validated a freely available, semi-automated pathway to build 3D virtual reality (VR) and hand-held, stereolithograph models. To evaluate whether surface visualization in 3D was more informative than in 2D, undergraduate students (n = 50) used the Gillespie scale to rate 3D VR and physical models of both a living patient-volunteer's brain and the skull of Phineas Gage, a historically famous railroad worker whose misfortune with a projectile tamping iron provided the first evidence of a structure-function relationship in brain. Using our processing pathway, we successfully fabricated human brain and skull replicas and validated that the stereolithograph model preserved the scale of the VR model. Based on the Gillespie ratings, students indicated that the biological utility and quality of visual information at the surface of VR and stereolithograph models were greater than the 2D images from which they were derived. The method we developed is useful to create VR and stereolithograph 3D models from medical images and can be used to model hard or soft tissue in living or preserved specimens. Compared to 2D images, VR and stereolithograph models provide an extra dimension that enhances both the quality of visual information and utility of surface visualization in neuroscience and medicine. PMID:17971879

  19. MOSSFRAC: An anisotropic 3D fracture model

    SciTech Connect

    Moss, W C; Levatin, J L

    2006-08-14

    Despite the intense effort for nearly half a century to construct detailed numerical models of plastic flow and plastic damage accumulation, models for describing fracture, an equally important damage mechanism still cannot describe basic fracture phenomena. Typical fracture models set the stress tensor to zero for tensile fracture and set the deviatoric stress tensor to zero for compressive fracture. One consequence is that the simple case of the tensile fracture of a cylinder under combined compressive radial and tensile axial loads is not modeled correctly. The experimental result is a cylinder that can support compressive radial loads, but no axial load, whereas, the typical numerical result is a cylinder with all stresses equal to zero. This incorrect modeling of fracture locally also has a global effect, because material that is fracturing produces stress release waves, which propagate from the fracture and influence the surrounding material. Consequently, it would be useful to have a model that can describe the stress relief and the resulting anisotropy due to fracture. MOSSFRAC is a material model that simulates three-dimensional tensile and shear fracture in initially isotropic elastic-plastic materials, although its framework is also amenable to initially anisotropic materials. It differs from other models by accounting for the effects of cracks on the constitutive response of the material, so that the previously described experiment, as well as complicated fracture scenarios are simulated more accurately. The model is implemented currently in the LLNL hydrocodes DYNA3D, PARADYN, and ALE3D. The purpose of this technical note is to present a complete qualitative description of the model and quantitative descriptions of salient features.

  20. 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.

  1. 3D Stratigraphic Modeling of Central Aachen

    NASA Astrophysics Data System (ADS)

    Dong, M.; Neukum, C.; Azzam, R.; Hu, H.

    2010-05-01

    Since 1980s, advanced computer hardware and software technologies, as well as multidisciplinary research have provided possibilities to develop advanced three dimensional (3D) simulation software for geosciences application. Some countries, such as USA1) and Canada2) 3), have built up regional 3D geological models based on archival geological data. Such models have played huge roles in engineering geology2), hydrogeology2) 3), geothermal industry1) and so on. In cooperating with the Municipality of Aachen, the Department of Engineering Geology of RWTH Aachen University have built up a computer-based 3D stratigraphic model of 50 meter' depth for the center of Aachen, which is a 5 km by 7 km geologically complex area. The uncorrelated data from multi-resources, discontinuous nature and unconformable connection of the units are main challenges for geological modeling in this area. The reliability of 3D geological models largely depends on the quality and quantity of data. Existing 1D and 2D geological data were collected, including 1) approximately 6970 borehole data of different depth compiled in Microsoft Access database and MapInfo database; 2) a Digital Elevation Model (DEM); 3) geological cross sections; and 4) stratigraphic maps in 1m, 2m and 5m depth. Since acquired data are of variable origins, they were managed step by step. The main processes are described below: 1) Typing errors of borehole data were identified and the corrected data were exported to Variowin2.2 to distinguish duplicate points; 2) The surface elevation of borehole data was compared to the DEM, and differences larger than 3m were eliminated. Moreover, where elevation data missed, it was read from the DEM; 3) Considerable data were collected from municipal constructions, such as residential buildings, factories, and roads. Therefore, many boreholes are spatially clustered, and only one or two representative points were picked out in such areas; After above procedures, 5839 boreholes with -x

  2. Emergent Stratification in Solid Tumors Selects for Reduced Cohesion of Tumor Cells: A Multi-Cell, Virtual-Tissue Model of Tumor Evolution Using CompuCell3D

    PubMed Central

    Swat, Maciej H.; Thomas, Gilberto L.; Shirinifard, Abbas; Clendenon, Sherry G.; Glazier, James A.

    2015-01-01

    Tumor cells and structure both evolve due to heritable variation of cell behaviors and selection over periods of weeks to years (somatic evolution). Micro-environmental factors exert selection pressures on tumor-cell behaviors, which influence both the rate and direction of evolution of specific behaviors, especially the development of tumor-cell aggression and resistance to chemotherapies. In this paper, we present, step-by-step, the development of a multi-cell, virtual-tissue model of tumor somatic evolution, simulated using the open-source CompuCell3D modeling environment. Our model includes essential cell behaviors, microenvironmental components and their interactions. Our model provides a platform for exploring selection pressures leading to the evolution of tumor-cell aggression, showing that emergent stratification into regions with different cell survival rates drives the evolution of less cohesive cells with lower levels of cadherins and higher levels of integrins. Such reduced cohesivity is a key hallmark in the progression of many types of solid tumors. PMID:26083246

  3. Emergent Stratification in Solid Tumors Selects for Reduced Cohesion of Tumor Cells: A Multi-Cell, Virtual-Tissue Model of Tumor Evolution Using CompuCell3D.

    PubMed

    Swat, Maciej H; Thomas, Gilberto L; Shirinifard, Abbas; Clendenon, Sherry G; Glazier, James A

    2015-01-01

    Tumor cells and structure both evolve due to heritable variation of cell behaviors and selection over periods of weeks to years (somatic evolution). Micro-environmental factors exert selection pressures on tumor-cell behaviors, which influence both the rate and direction of evolution of specific behaviors, especially the development of tumor-cell aggression and resistance to chemotherapies. In this paper, we present, step-by-step, the development of a multi-cell, virtual-tissue model of tumor somatic evolution, simulated using the open-source CompuCell3D modeling environment. Our model includes essential cell behaviors, microenvironmental components and their interactions. Our model provides a platform for exploring selection pressures leading to the evolution of tumor-cell aggression, showing that emergent stratification into regions with different cell survival rates drives the evolution of less cohesive cells with lower levels of cadherins and higher levels of integrins. Such reduced cohesivity is a key hallmark in the progression of many types of solid tumors. PMID:26083246

  4. 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.

  5. Combinatorial Pharmacophore-Based 3D-QSAR Analysis and Virtual Screening of FGFR1 Inhibitors

    PubMed Central

    Zhou, Nannan; Xu, Yuan; Liu, Xian; Wang, Yulan; Peng, Jianlong; Luo, Xiaomin; Zheng, Mingyue; Chen, Kaixian; Jiang, Hualiang

    2015-01-01

    The fibroblast growth factor/fibroblast growth factor receptor (FGF/FGFR) signaling pathway plays crucial roles in cell proliferation, angiogenesis, migration, and survival. Aberration in FGFRs correlates with several malignancies and disorders. FGFRs have proved to be attractive targets for therapeutic intervention in cancer, and it is of high interest to find FGFR inhibitors with novel scaffolds. In this study, a combinatorial three-dimensional quantitative structure-activity relationship (3D-QSAR) model was developed based on previously reported FGFR1 inhibitors with diverse structural skeletons. This model was evaluated for its prediction performance on a diverse test set containing 232 FGFR inhibitors, and it yielded a SD value of 0.75 pIC50 units from measured inhibition affinities and a Pearson’s correlation coefficient R2 of 0.53. This result suggests that the combinatorial 3D-QSAR model could be used to search for new FGFR1 hit structures and predict their potential activity. To further evaluate the performance of the model, a decoy set validation was used to measure the efficiency of the model by calculating EF (enrichment factor). Based on the combinatorial pharmacophore model, a virtual screening against SPECS database was performed. Nineteen novel active compounds were successfully identified, which provide new chemical starting points for further structural optimization of FGFR1 inhibitors. PMID:26110383

  6. Teaching the geological subsurface with 3D models

    NASA Astrophysics Data System (ADS)

    Thorpe, Steve; Ward, Emma

    2014-05-01

    along with accompanying education material and a video tutorial guide are currently available to the public on our website www.bgs.ac.uk. 2014 will see the launch of a further 5-6 models, each illustrating different geological locations, rock types and complexities. This poster aims to show the methodology and techniques for generating a 3D geological model. It will provide background information on the project and how these models can be used as a teaching resource, either in a formal classroom setting or as a distance learning tool. The model allows the student to take part in virtual fieldwork, by viewing the landscape in association with the geological structures and processes that have shaped it.

  7. 3D Modeling of Equatorial Plasma Bubbles

    NASA Astrophysics Data System (ADS)

    Huba, Joseph; Joyce, Glenn; Krall, Jonathan

    2011-10-01

    Post-sunset ionospheric irregularities in the equatorial F region were first observed by Booker and Wells (1938) using ionosondes. This phenomenon has become known as equatorial spread F (ESF). During ESF the equatorial ionosphere becomes unstable because of a Rayleigh-Taylor-like instability: large scale (10s km) electron density ``bubbles'' can develop and rise to high altitudes (1000 km or greater at times). Understanding and modeling ESF is important because of its impact on space weather: it causes radio wave scintillation that degrades communication and navigation systems. In fact, it is the focus of of the Air Force Communications/Navigation Outage Forecast Satellite (C/NOFS) mission. We will describe 3D simulation results from the NRL ionosphere models SAMI3 and SAMI3/ESF of this phenomenon. In particular, we will examine the causes of the day-to-day ariability of ESF which is an unresolved problem at this time. Post-sunset ionospheric irregularities in the equatorial F region were first observed by Booker and Wells (1938) using ionosondes. This phenomenon has become known as equatorial spread F (ESF). During ESF the equatorial ionosphere becomes unstable because of a Rayleigh-Taylor-like instability: large scale (10s km) electron density ``bubbles'' can develop and rise to high altitudes (1000 km or greater at times). Understanding and modeling ESF is important because of its impact on space weather: it causes radio wave scintillation that degrades communication and navigation systems. In fact, it is the focus of of the Air Force Communications/Navigation Outage Forecast Satellite (C/NOFS) mission. We will describe 3D simulation results from the NRL ionosphere models SAMI3 and SAMI3/ESF of this phenomenon. In particular, we will examine the causes of the day-to-day ariability of ESF which is an unresolved problem at this time. Research supported by ONR.

  8. Research on the key technologies of 3D spatial data organization and management for virtual building environments

    NASA Astrophysics Data System (ADS)

    Gong, Jun; Zhu, Qing

    2006-10-01

    As the special case of VGE in the fields of AEC (architecture, engineering and construction), Virtual Building Environment (VBE) has been broadly concerned. Highly complex, large-scale 3d spatial data is main bottleneck of VBE applications, so 3d spatial data organization and management certainly becomes the core technology for VBE. This paper puts forward 3d spatial data model for VBE, and the performance to implement it is very high. Inherent storage method of CAD data makes data redundant, and doesn't concern efficient visualization, which is a practical bottleneck to integrate CAD model, so An Efficient Method to Integrate CAD Model Data is put forward. Moreover, Since the 3d spatial indices based on R-tree are usually limited by their weakness of low efficiency due to the severe overlap of sibling nodes and the uneven size of nodes, a new node-choosing algorithm of R-tree are proposed.

  9. Reservoir geology using 3D modelling tools

    SciTech Connect

    Dubrule, O.; Samson, P.; Segonds, D.

    1996-12-31

    The last decade has seen tremendous developments in the area of quantitative geological modelling. These developments have a significant impact on the current practice of constructing reservoir models. A structural model can first be constructed on the basis of depth-converted structural interpretations produced on a seismic interpretation workstation. Surfaces and faults can be represented as geological objects, and interactively modified. Once the tectonic framework has been obtained, intermediate stratigraphic surfaces can be constructed between the main structural surfaces. Within each layer, reservoir attributes can be represented using various techniques. Examples show how the distribution of different facies (i.e. from fine to coarse grain) can be represented, or how various depositional units (for instance channels, crevasses and lobes in a turbidite setting) can be modelled as geological {open_quotes}objects{close_quotes} with complex geometries. Elf Aquitaine, in close co-operation with the GOCAD project in Nancy (France) is investigating how geological models can be made more realistic by developing interactive functionalities. Examples show that, contrary to standard deterministic or geostatistical modelling techniques (which tend to be difficult to control) the use of new 3D tools allows the geologist to interactively modify geological surfaces (including faults) or volumetric properties. Thus, the sensitivity of various economic parameters (oil in place, connected volumes, reserves) to major geological uncertainties can be evaluated. It is argued that future breakthroughs in geological modelling techniques are likely to happen in the development of interactive approaches rather than in the research of new mathematical algorithms.

  10. Reservoir geology using 3D modelling tools

    SciTech Connect

    Dubrule, O. ); Samson, P. ); Segonds, D. )

    1996-01-01

    The last decade has seen tremendous developments in the area of quantitative geological modelling. These developments have a significant impact on the current practice of constructing reservoir models. A structural model can first be constructed on the basis of depth-converted structural interpretations produced on a seismic interpretation workstation. Surfaces and faults can be represented as geological objects, and interactively modified. Once the tectonic framework has been obtained, intermediate stratigraphic surfaces can be constructed between the main structural surfaces. Within each layer, reservoir attributes can be represented using various techniques. Examples show how the distribution of different facies (i.e. from fine to coarse grain) can be represented, or how various depositional units (for instance channels, crevasses and lobes in a turbidite setting) can be modelled as geological [open quotes]objects[close quotes] with complex geometries. Elf Aquitaine, in close co-operation with the GOCAD project in Nancy (France) is investigating how geological models can be made more realistic by developing interactive functionalities. Examples show that, contrary to standard deterministic or geostatistical modelling techniques (which tend to be difficult to control) the use of new 3D tools allows the geologist to interactively modify geological surfaces (including faults) or volumetric properties. Thus, the sensitivity of various economic parameters (oil in place, connected volumes, reserves) to major geological uncertainties can be evaluated. It is argued that future breakthroughs in geological modelling techniques are likely to happen in the development of interactive approaches rather than in the research of new mathematical algorithms.

  11. Fusion of image and laser-scanning data in a large-scale 3D virtual environment

    NASA Astrophysics Data System (ADS)

    Shih, Jhih-Syuan; Lin, Ta-Te

    2013-05-01

    Construction of large-scale 3D virtual environment is important in many fields such as robotic navigation, urban planning, transportation, and remote sensing, etc. Laser scanning approach is the most common method used in constructing 3D models. This paper proposes an automatic method to fuse image and laser-scanning data in a large-scale 3D virtual environment. The system comprises a laser-scanning device installed on a robot platform and the software for data fusion and visualization. The algorithms of data fusion and scene integration are presented. Experiments were performed for the reconstruction of outdoor scenes to test and demonstrate the functionality of the system. We also discuss the efficacy of the system and technical problems involved in this proposed method.

  12. 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.

  13. 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…

  14. Exploiting Textured 3D Models for Developing Serious Games

    NASA Astrophysics Data System (ADS)

    Kontogianni, G.; Georgopoulos, A.

    2015-08-01

    Digital technologies have affected significantly many fields of computer graphics such as Games and especially the field of the Serious Games. These games are usually used for educational proposes in many fields such as Health Care, Military applications, Education, Government etc. Especially Digital Cultural Heritage is a scientific area that Serious Games are applied and lately many applications appear in the related literature. Realistic 3D textured models which have been produced using different photogrammetric methods could be a useful tool for the creation of Serious Game applications in order to make the final result more realistic and close to the reality. The basic goal of this paper is how 3D textured models which are produced by photogrammetric methods can be useful for developing a more realistic environment of a Serious Game. The application of this project aims at the creation of an educational game for the Ancient Agora of Athens. The 3D models used vary not only as far as their production methods (i.e. Time of Flight laser scanner, Structure from Motion, Virtual historical reconstruction etc.) is concerned, but also as far as their era as some of them illustrated according to their existing situation and some others according to how these monuments looked like in the past. The Unity 3D® game developing environment was used for creating this application, in which all these models were inserted in the same file format. For the application two diachronic virtual tours of the Athenian Agora were produced. The first one illustrates the Agora as it is today and the second one at the 2nd century A.D. Finally the future perspective for the evolution of this game is presented which includes the addition of some questions that the user will be able to answer. Finally an evaluation is scheduled to be performed at the end of the project.

  15. Regional geothermal 3D modelling in Denmark

    NASA Astrophysics Data System (ADS)

    Poulsen, S. E.; Balling, N.; Bording, T. S.; Nielsen, S. B.

    2012-04-01

    In the pursuit of sustainable and low carbon emission energy sources, increased global attention has been given to the exploration and exploitation of geothermal resources within recent decades. In 2009 a national multi-disciplinary geothermal research project was established. As a significant part of this project, 3D temperature modelling is to be carried out, with special emphasis on temperatures of potential geothermal reservoirs in the Danish area. The Danish subsurface encompasses low enthalpy geothermal reservoirs of mainly Triassic and Jurassic age. Geothermal plants at Amager (Copenhagen) and Thisted (Northern Jutland) have the capacity of supplying the district heating network with up to 14 MW and 7 MW, respectively, by withdrawing warm pore water from the Gassum (Lower Jurassic/Upper Triassic) and Bunter (Lower Triassic) sandstone reservoirs, respectively. Explorative studies of the subsurface temperature regime typically are based on a combination of observations and modelling. In this study, the open-source groundwater modelling code MODFLOW is modified to simulate the subsurface temperature distribution in three dimensions by taking advantage of the mathematical similarity between saturated groundwater flow (Darcy flow) and heat conduction. A numerical model of the subsurface geology in Denmark is built and parameterized from lithological information derived from joint interpretation of seismic surveys and borehole information. Boundary conditions are constructed from knowledge about the heat flow from the Earth's interior and the shallow ground temperature. Matrix thermal conductivities have been estimated from analysis of high-resolution temperature logs measured in deep wells and porosity-depth relations are included using interpreted main lithologies. The model takes into account the dependency of temperature and pressure on thermal conductivity. Moreover, a transient model based correction of the paleoclimatic thermal disturbance caused by the

  16. 3-D physical models of amitosis (cytokinesis).

    PubMed

    Cheng, Kang; Zou, Changhua

    2005-01-01

    Based on Newton's laws, extended Coulomb's law and published biological data, we develop our 3-D physical models of natural and normal amitosis (cytokinesis), for prokaryotes (bacterial cells) in M phase. We propose following hypotheses: Chromosome rings exclusion: No normally and naturally replicated chromosome rings (RCR) can occupy the same prokaryote, a bacterial cell. The RCR produce spontaneous and strong electromagnetic fields (EMF), that can be alternated environmentally, in protoplasm and cortex. The EMF is approximately a repulsive quasi-static electric (slowly variant and mostly electric) field (EF). The EF forces between the RCR are strong enough, and orderly accumulate contractile proteins that divide the procaryotes in the cell cortex of division plane or directly split the cell compartment envelope longitudinally. The radial component of the EF forces could also make furrows or cleavages of procaryotes. The EF distribution controls the protoplasm partition and completes the amitosis (cytokinesis). After the cytokinesis, the spontaneous and strong EF disappear because the net charge accumulation becomes weak, in the protoplasm. The exclusion is because the two sets of informative objects (RCR) have identical DNA codes information and they are electro magnetically identical, therefore they repulse from each other. We also compare divisions among eukaryotes, prokaryotes, mitochondria and chloroplasts and propose our hypothesis: The principles of our models are applied to divisions of mitochondria and chloroplasts of eucaryotes too because these division mechanisms are closer than others in a view of physics. Though we develop our model using 1 division plane (i.e., 1 cell is divided into 2 cells) as an example, the principle of our model is applied to the cases with multiple division planes (i.e., 1 cell is divided into multiple cells) too. PMID:15533619

  17. 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…

  18. 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…

  19. Inertial Sensor-Based Touch and Shake Metaphor for Expressive Control of 3D Virtual Avatars.

    PubMed

    Patil, Shashidhar; Chintalapalli, Harinadha Reddy; Kim, Dubeom; Chai, Youngho

    2015-01-01

    In this paper, we present an inertial sensor-based touch and shake metaphor for expressive control of a 3D virtual avatar in a virtual environment. An intuitive six degrees-of-freedom wireless inertial motion sensor is used as a gesture and motion control input device with a sensor fusion algorithm. The algorithm enables user hand motions to be tracked in 3D space via magnetic, angular rate, and gravity sensors. A quaternion-based complementary filter is implemented to reduce noise and drift. An algorithm based on dynamic time-warping is developed for efficient recognition of dynamic hand gestures with real-time automatic hand gesture segmentation. Our approach enables the recognition of gestures and estimates gesture variations for continuous interaction. We demonstrate the gesture expressivity using an interactive flexible gesture mapping interface for authoring and controlling a 3D virtual avatar and its motion by tracking user dynamic hand gestures. This synthesizes stylistic variations in a 3D virtual avatar, producing motions that are not present in the motion database using hand gesture sequences from a single inertial motion sensor. PMID:26094629

  20. The Cognitive Apprenticeship Theory for the Teaching of Mathematics in an Online 3D Virtual Environment

    ERIC Educational Resources Information Center

    Bouta, Hara; Paraskeva, Fotini

    2013-01-01

    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.…

  1. 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…

  2. Inertial Sensor-Based Touch and Shake Metaphor for Expressive Control of 3D Virtual Avatars

    PubMed Central

    Patil, Shashidhar; Chintalapalli, Harinadha Reddy; Kim, Dubeom; Chai, Youngho

    2015-01-01

    In this paper, we present an inertial sensor-based touch and shake metaphor for expressive control of a 3D virtual avatar in a virtual environment. An intuitive six degrees-of-freedom wireless inertial motion sensor is used as a gesture and motion control input device with a sensor fusion algorithm. The algorithm enables user hand motions to be tracked in 3D space via magnetic, angular rate, and gravity sensors. A quaternion-based complementary filter is implemented to reduce noise and drift. An algorithm based on dynamic time-warping is developed for efficient recognition of dynamic hand gestures with real-time automatic hand gesture segmentation. Our approach enables the recognition of gestures and estimates gesture variations for continuous interaction. We demonstrate the gesture expressivity using an interactive flexible gesture mapping interface for authoring and controlling a 3D virtual avatar and its motion by tracking user dynamic hand gestures. This synthesizes stylistic variations in a 3D virtual avatar, producing motions that are not present in the motion database using hand gesture sequences from a single inertial motion sensor. PMID:26094629

  3. 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…

  4. 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…

  5. 3D Models of Stellar Interactions

    NASA Astrophysics Data System (ADS)

    Mohamed, S.; Podsiadlowski, Ph.; Booth, R.; Maercker, M.; Ramstedt, S.; Vlemmings, W.; Harries, T.; Mackey, J.; Langer, N.; Corradi, R.

    2014-04-01

    Symbiotic binaries consist of a cool, evolved mass-losing giant and an accreting compact companion. As symbiotic nebulae show similar morphologies to those in planetary nebulae (so much so that it is often difficult to distinguish between the two), they are ideal laboratories for understanding the role a binary companion plays in shaping the circumstellar envelopes in these evolved systems. We will present 3D Smoothed Particle Hydrodynamics (SPH) models of interacting binaries, e.g. R Aquarii and Mira, and discuss the formation of spiral outflows, arcs, shells and equatorial density enhancements.We will also discuss the implications of the former for planetary nebulae, e.g. the Egg Nebula and Cat's Eye, and the latter for the formation of bipolar geometries, e.g. M2-9. We also investigate accretion and angular momentum evolution in symbiotic binaries which may be important to understand the formation of jets and more episodic mass-loss features we see in circumstellar envelopes and the orbital characteristics of binary central stars of planetary nebulae.

  6. 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

  7. 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. PMID:12223495

  8. Multi-view and 3D deformable part models.

    PubMed

    Pepik, Bojan; Stark, Michael; Gehler, Peter; Schiele, Bernt

    2015-11-01

    As objects are inherently 3D, they have been modeled in 3D in the early days of computer vision. Due to the ambiguities arising from mapping 2D features to 3D models, 3D object representations have been neglected and 2D feature-based models are the predominant paradigm in object detection nowadays. While such models have achieved outstanding bounding box detection performance, they come with limited expressiveness, as they are clearly limited in their capability of reasoning about 3D shape or viewpoints. In this work, we bring the worlds of 3D and 2D object representations closer, by building an object detector which leverages the expressive power of 3D object representations while at the same time can be robustly matched to image evidence. To that end, we gradually extend the successful deformable part model [1] to include viewpoint information and part-level 3D geometry information, resulting in several different models with different level of expressiveness. We end up with a 3D object model, consisting of multiple object parts represented in 3D and a continuous appearance model. We experimentally verify that our models, while providing richer object hypotheses than the 2D object models, provide consistently better joint object localization and viewpoint estimation than the state-of-the-art multi-view and 3D object detectors on various benchmarks (KITTI [2] , 3D object classes [3] , Pascal3D+ [4] , Pascal VOC 2007 [5] , EPFL multi-view cars[6] ). PMID:26440264

  9. CityGML - Interoperable semantic 3D city models

    NASA Astrophysics Data System (ADS)

    Gröger, Gerhard; Plümer, Lutz

    2012-07-01

    CityGML is the international standard of the Open Geospatial Consortium (OGC) for the representation and exchange of 3D city models. It defines the three-dimensional geometry, topology, semantics and appearance of the most relevant topographic objects in urban or regional contexts. These definitions are provided in different, well-defined Levels-of-Detail (multiresolution model). The focus of CityGML is on the semantical aspects of 3D city models, its structures, taxonomies and aggregations, allowing users to employ virtual 3D city models for advanced analysis and visualization tasks in a variety of application domains such as urban planning, indoor/outdoor pedestrian navigation, environmental simulations, cultural heritage, or facility management. This is in contrast to purely geometrical/graphical models such as KML, VRML, or X3D, which do not provide sufficient semantics. CityGML is based on the Geography Markup Language (GML), which provides a standardized geometry model. Due to this model and its well-defined semantics and structures, CityGML facilitates interoperable data exchange in the context of geo web services and spatial data infrastructures. Since its standardization in 2008, CityGML has become used on a worldwide scale: tools from notable companies in the geospatial field provide CityGML interfaces. Many applications and projects use this standard. CityGML is also having a strong impact on science: numerous approaches use CityGML, particularly its semantics, for disaster management, emergency responses, or energy-related applications as well as for visualizations, or they contribute to CityGML, improving its consistency and validity, or use CityGML, particularly its different Levels-of-Detail, as a source or target for generalizations. This paper gives an overview of CityGML, its underlying concepts, its Levels-of-Detail, how to extend it, its applications, its likely future development, and the role it plays in scientific research. Furthermore, its

  10. Using virtual 3D audio in multispeech channel and multimedia environments

    NASA Astrophysics Data System (ADS)

    Orosz, Michael D.; Karplus, Walter J.; Balakrishnan, Jerry D.

    2000-08-01

    The advantages and disadvantages of using virtual 3-D audio in mission-critical, multimedia display interfaces were evaluated. The 3D audio platform seems to be an especially promising candidate for aircraft cockpits, flight control rooms, and other command and control environments in which operators must make mission-critical decisions while handling demanding and routine tasks. Virtual audio signal processing creates the illusion for a listener wearing conventional earphones that each of a multiplicity of simultaneous speech or audio channels is originating from a different, program- specified location in virtual space. To explore the possible uses of this new, readily available technology, a test bed simulating some of the conditions experienced by the chief flight test coordinator at NASA's Dryden Flight Research Center was designed and implemented. Thirty test subjects simultaneously performed routine tasks requiring constant hand-eye coordination, while monitoring four speech channels, each generating continuous speech signals, for the occurrence of pre-specified keywords. Performance measures included accuracy in identifying the keywords, accuracy in identifying the speaker of the keyword, and response time. We found substantial improvements on all of these measures when comparing virtual audio with conventional, monaural transmissions. We also explored the effect on operator performance of different spatial configurations of the audio sources in 3-D space, simulated movement (dither) in the source locations, and of providing graphical redundancy. Some of these manipulations were less effective and may even decrease performance efficiency, even though they improve some aspects of the virtual space simulation.

  11. 3D-ANTLERS: Virtual Reconstruction and Three-Dimensional Measurement

    NASA Astrophysics Data System (ADS)

    Barba, S.; Fiorillo, F.; De Feo, E.

    2013-02-01

    . In the ARTEC digital mock-up for example, it shows the ability to select the individual frames, already polygonal and geo-referenced at the time of capture; however, it is not possible to make an automated texturization differently from the low-cost environment which allows to produce a good graphics' definition. Once the final 3D models were obtained, we have proceeded to do a geometric and graphic comparison of the results. Therefore, in order to provide an accuracy requirement and an assessment for the 3D reconstruction we have taken into account the following benchmarks: cost, captured points, noise (local and global), shadows and holes, operability, degree of definition, quality and accuracy. Subsequently, these studies carried out in an empirical way on the virtual reconstructions, a 3D documentation was codified with a procedural method endorsing the use of terrestrial sensors for the documentation of antlers. The results thus pursued were compared with the standards set by the current provisions (see "Manual de medición" of Government of Andalusia-Spain); to date, in fact, the identification is based on data such as length, volume, colour, texture, openness, tips, structure, etc. Data, which is currently only appreciated with traditional instruments, such as tape measure, would be well represented by a process of virtual reconstruction and cataloguing.

  12. 3D-GNOME: an integrated web service for structural modeling of the 3D genome

    PubMed Central

    Szalaj, Przemyslaw; Michalski, Paul J.; Wróblewski, Przemysław; Tang, Zhonghui; Kadlof, Michal; Mazzocco, Giovanni; Ruan, Yijun; Plewczynski, Dariusz

    2016-01-01

    Recent advances in high-throughput chromosome conformation capture (3C) technology, such as Hi-C and ChIA-PET, have demonstrated the importance of 3D genome organization in development, cell differentiation and transcriptional regulation. There is now a widespread need for computational tools to generate and analyze 3D structural models from 3C data. Here we introduce our 3D GeNOme Modeling Engine (3D-GNOME), a web service which generates 3D structures from 3C data and provides tools to visually inspect and annotate the resulting structures, in addition to a variety of statistical plots and heatmaps which characterize the selected genomic region. Users submit a bedpe (paired-end BED format) file containing the locations and strengths of long range contact points, and 3D-GNOME simulates the structure and provides a convenient user interface for further analysis. Alternatively, a user may generate structures using published ChIA-PET data for the GM12878 cell line by simply specifying a genomic region of interest. 3D-GNOME is freely available at http://3dgnome.cent.uw.edu.pl/. PMID:27185892

  13. 3D-GNOME: an integrated web service for structural modeling of the 3D genome.

    PubMed

    Szalaj, Przemyslaw; Michalski, Paul J; Wróblewski, Przemysław; Tang, Zhonghui; Kadlof, Michal; Mazzocco, Giovanni; Ruan, Yijun; Plewczynski, Dariusz

    2016-07-01

    Recent advances in high-throughput chromosome conformation capture (3C) technology, such as Hi-C and ChIA-PET, have demonstrated the importance of 3D genome organization in development, cell differentiation and transcriptional regulation. There is now a widespread need for computational tools to generate and analyze 3D structural models from 3C data. Here we introduce our 3D GeNOme Modeling Engine (3D-GNOME), a web service which generates 3D structures from 3C data and provides tools to visually inspect and annotate the resulting structures, in addition to a variety of statistical plots and heatmaps which characterize the selected genomic region. Users submit a bedpe (paired-end BED format) file containing the locations and strengths of long range contact points, and 3D-GNOME simulates the structure and provides a convenient user interface for further analysis. Alternatively, a user may generate structures using published ChIA-PET data for the GM12878 cell line by simply specifying a genomic region of interest. 3D-GNOME is freely available at http://3dgnome.cent.uw.edu.pl/. PMID:27185892

  14. 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. PMID:27046584

  15. 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.

  16. 3D fast wavelet network model-assisted 3D face recognition

    NASA Astrophysics Data System (ADS)

    Said, Salwa; Jemai, Olfa; Zaied, Mourad; Ben Amar, Chokri

    2015-12-01

    In last years, the emergence of 3D shape in face recognition is due to its robustness to pose and illumination changes. These attractive benefits are not all the challenges to achieve satisfactory recognition rate. Other challenges such as facial expressions and computing time of matching algorithms remain to be explored. In this context, we propose our 3D face recognition approach using 3D wavelet networks. Our approach contains two stages: learning stage and recognition stage. For the training we propose a novel algorithm based on 3D fast wavelet transform. From 3D coordinates of the face (x,y,z), we proceed to voxelization to get a 3D volume which will be decomposed by 3D fast wavelet transform and modeled after that with a wavelet network, then their associated weights are considered as vector features to represent each training face . For the recognition stage, an unknown identity face is projected on all the training WN to obtain a new vector features after every projection. A similarity score is computed between the old and the obtained vector features. To show the efficiency of our approach, experimental results were performed on all the FRGC v.2 benchmark.

  17. A 3-D shape model of Interamnia

    NASA Astrophysics Data System (ADS)

    Sato, Isao

    2015-08-01

    A 3-D shape model of the sixth largest of the main belt asteroids, (704) Interamnia, is presented. The model is reproduced from its two stellar occultation observations and six lightcurves between 1969 and 2011. The first stellar occultation was the occultation of TYC 234500183 on 1996 December 17 observed from 13 sites in the USA. An elliptical cross section of (344.6±9.6km)×(306.2±9.1km), for position angle P=73.4±12.5 was fitted. The lightcurve around the occultation shows that the peak-to-peak amplitude was 0.04 mag. and the occultation phase was just before the minimum. The second stellar occultation was the occultation of HIP 036189 on 2003 March 23 observed from 39 sites in Japan and Hawaii. An elliptical cross section of (349.8±0.9km)×(303.7±1.7km), for position angle P=86.0±1.1 was fitted. A companion of 8.5 mag. of the occulted star was discovered whose separation is 12±2 mas (milli-arcseconds), P=148±11 . A combined analysis of rotational lightcurves and occultation chords can return more information than can be obtained with either technique alone. From follow-up photometric observations of the asteroid between 2003 and 2011, its rotation period is determined to be 8.728967167±0.00000007 hours, which is accurate enough to fix the rotation phases at other occultation events. The derived north pole is λ2000=259±8, β2000=-50±5 (retrograde rotation); the lengths of the three principal axes are 2a=361.8±2.8km, 2b=324.4±5.0km, 2c=297.3±3.5km, and the mean diameter is D=326.8±3.0km. Supposing the mass of Interamnia as (3.5±0.9)×10-11 solar masses, the density is then ρ=3.8±1.0 g cm-3.

  18. Modulation of cortical activity in 2D versus 3D virtual reality environments: an EEG study.

    PubMed

    Slobounov, Semyon M; Ray, William; Johnson, Brian; Slobounov, Elena; Newell, Karl M

    2015-03-01

    There is a growing empirical evidence that virtual reality (VR) is valuable for education, training, entertaining and medical rehabilitation due to its capacity to represent real-life events and situations. However, the neural mechanisms underlying behavioral confounds in VR environments are still poorly understood. In two experiments, we examined the effect of fully immersive 3D stereoscopic presentations and less immersive 2D VR environments on brain functions and behavioral outcomes. In Experiment 1 we examined behavioral and neural underpinnings of spatial navigation tasks using electroencephalography (EEG). In Experiment 2, we examined EEG correlates of postural stability and balance. Our major findings showed that fully immersive 3D VR induced a higher subjective sense of presence along with enhanced success rate of spatial navigation compared to 2D. In Experiment 1 power of frontal midline EEG (FM-theta) was significantly higher during the encoding phase of route presentation in the 3D VR. In Experiment 2, the 3D VR resulted in greater postural instability and modulation of EEG patterns as a function of 3D versus 2D environments. The findings support the inference that the fully immersive 3D enriched-environment requires allocation of more brain and sensory resources for cognitive/motor control during both tasks than 2D presentations. This is further evidence that 3D VR tasks using EEG may be a promising approach for performance enhancement and potential applications in clinical/rehabilitation settings. PMID:25448267

  19. Automatic Assessment of 3D Modeling Exams

    ERIC Educational Resources Information Center

    Sanna, A.; Lamberti, F.; Paravati, G.; Demartini, C.

    2012-01-01

    Computer-based assessment of exams provides teachers and students with two main benefits: fairness and effectiveness in the evaluation process. This paper proposes a fully automatic evaluation tool for the Graphic and Virtual Design (GVD) curriculum at the First School of Architecture of the Politecnico di Torino, Italy. In particular, the tool is…

  20. 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.

  1. Representing 3D virtual objects: interaction between visuo-spatial ability and type of exploration.

    PubMed

    Meijer, Frank; van den Broek, Egon L

    2010-03-17

    We investigated individual differences in interactively exploring 3D virtual objects. 36 participants explored 24 simple and 24 difficult objects (composed of respectively three and five Biederman geons) actively, passively, or not at all. Both their 3D mental representation of the objects and visuo-spatial ability was assessed. Results show that, regardless of the object's complexity, people with a low VSA benefit from active exploration of objects, where people with a middle or high VSA do not. These findings extend and refine earlier research on interactively learning visuo-spatial information and underline the importance to take individual differences into account. PMID:20116394

  2. 3D Modeling Techniques for Print and Digital Media

    NASA Astrophysics Data System (ADS)

    Stephens, Megan Ashley

    In developing my thesis, I looked to gain skills using ZBrush to create 3D models, 3D scanning, and 3D printing. The models created compared the hearts of several vertebrates and were intended for students attending Comparative Vertebrate Anatomy. I used several resources to create a model of the human heart and was able to work from life while creating heart models from other vertebrates. I successfully learned ZBrush and 3D scanning, and successfully printed 3D heart models. ZBrush allowed me to create several intricate models for use in both animation and print media. The 3D scanning technique did not fit my needs for the project, but may be of use for later projects. I was able to 3D print using two different techniques as well.

  3. SEARCHBreast Workshop Proceedings: 3D Modelling of Breast Cancer.

    PubMed

    Morrissey, Bethny; Blyth, Karen; Carter, Phil; Chelala, Claude; Holen, Ingunn; Jones, Louise; Speirs, Valerie

    2015-12-01

    SEARCHBreast, a UK initiative supported by the NC3Rs, organised a workshop entitled 3D Modelling of Breast Cancer. The workshop focused on providing researchers with solutions to overcome some of the perceived barriers to working with human-derived tumour cells, cell lines and tissues, namely: a) the limited access to human-derived material; and b) the difficulty in working with these samples. The workshop presentations provided constructive advice and information on how to best prepare human cells or tissues for further downstream applications. Techniques in developing primary cultures from patient samples, and considerations when preserving tissue slices, were discussed. A common theme throughout the workshop was the importance of ensuring that the cells are grown in conditions as similar to the in vivo microenvironment as possible. Comparisons of the advantages of several in vitro options, such as primary cell cultures, cell line cultures, explants or tissue slices, suggest that all offer great potential applications for breast cancer research, and highlight that it need not be a case of choosing one over the other. The workshop also offered cutting-edge examples of on-chip technologies and 3-D tumour modelling by using virtual pathology, which can contribute to clinically relevant studies and provide insights into breast cancer metastatic mechanisms. PMID:26753939

  4. 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.

  5. Using the CAVE virtual-reality environment as an aid to 3-D electromagnetic field computation

    SciTech Connect

    Turner, L.R.; Levine, D.; Huang, M.; Papka, M; Kettunen, L.

    1995-08-01

    One of the major problems in three-dimensional (3-D) field computation is visualizing the resulting 3-D field distributions. A virtual-reality environment, such as the CAVE, (CAVE Automatic Virtual Environment) is helping to overcome this problem, thus making the results of computation more usable for designers and users of magnets and other electromagnetic devices. As a demonstration of the capabilities of the CAVE, the elliptical multipole wiggler (EMW), an insertion device being designed for the Advanced Photon Source (APS) now being commissioned at Argonne National Laboratory (ANL), wa made visible, along with its fields and beam orbits. Other uses of the CAVE in preprocessing and postprocessing computation for electromagnetic applications are also discussed.

  6. 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. PMID:8591413

  7. 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

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

    PubMed

    Hansen, Margaret M

    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

  9. Analysis of scalability of high-performance 3D image processing platform for virtual colonoscopy.

    PubMed

    Yoshida, Hiroyuki; Wu, Yin; Cai, Wenli

    2014-03-19

    One of the key challenges in three-dimensional (3D) medical imaging is to enable the fast turn-around time, which is often required for interactive or real-time response. This inevitably requires not only high computational power but also high memory bandwidth due to the massive amount of data that need to be processed. For this purpose, we previously developed a software platform for high-performance 3D medical image processing, called HPC 3D-MIP platform, which employs increasingly available and affordable commodity computing systems such as the multicore, cluster, and cloud computing systems. To achieve scalable high-performance computing, the platform employed size-adaptive, distributable block volumes as a core data structure for efficient parallelization of a wide range of 3D-MIP algorithms, supported task scheduling for efficient load distribution and balancing, and consisted of a layered parallel software libraries that allow image processing applications to share the common functionalities. We evaluated the performance of the HPC 3D-MIP platform by applying it to computationally intensive processes in virtual colonoscopy. Experimental results showed a 12-fold performance improvement on a workstation with 12-core CPUs over the original sequential implementation of the processes, indicating the efficiency of the platform. Analysis of performance scalability based on the Amdahl's law for symmetric multicore chips showed the potential of a high performance scalability of the HPC 3D-MIP platform when a larger number of cores is available. PMID:24910506

  10. Analysis of scalability of high-performance 3D image processing platform for virtual colonoscopy

    PubMed Central

    Yoshida, Hiroyuki; Wu, Yin; Cai, Wenli

    2014-01-01

    One of the key challenges in three-dimensional (3D) medical imaging is to enable the fast turn-around time, which is often required for interactive or real-time response. This inevitably requires not only high computational power but also high memory bandwidth due to the massive amount of data that need to be processed. For this purpose, we previously developed a software platform for high-performance 3D medical image processing, called HPC 3D-MIP platform, which employs increasingly available and affordable commodity computing systems such as the multicore, cluster, and cloud computing systems. To achieve scalable high-performance computing, the platform employed size-adaptive, distributable block volumes as a core data structure for efficient parallelization of a wide range of 3D-MIP algorithms, supported task scheduling for efficient load distribution and balancing, and consisted of a layered parallel software libraries that allow image processing applications to share the common functionalities. We evaluated the performance of the HPC 3D-MIP platform by applying it to computationally intensive processes in virtual colonoscopy. Experimental results showed a 12-fold performance improvement on a workstation with 12-core CPUs over the original sequential implementation of the processes, indicating the efficiency of the platform. Analysis of performance scalability based on the Amdahl’s law for symmetric multicore chips showed the potential of a high performance scalability of the HPC 3D-MIP platform when a larger number of cores is available. PMID:24910506

  11. 3D modeling of metallic grain growth

    SciTech Connect

    George, D.; Carlson, N.; Gammel, J.T.; Kuprat, A.

    1999-06-01

    This paper will describe simulating metallic grain growth using the Gradient Weighted Moving Finite Elements code, GRAIN3D. The authors also describe the set of mesh topology change operations developed to respond to changes in the physical topology such as the collapse of grains and to maintain uniform calculational mesh quality. Validation of the method is demonstrated by comparison to analytic calculations. The authors present results of multigrain simulations where grain boundaries evolve by mean curvature motion and include results which incorporate grain boundary orientation dependence.

  12. The 3D rocket combustor acoustics model

    NASA Technical Reports Server (NTRS)

    Priem, Richard J.; Breisacher, Kevin J.

    1992-01-01

    The theory and procedures for determining the characteristics of pressure oscillations in rocket engines with prescribed burning rate oscillations are presented. Analyses including radial and hub baffles and absorbers can be performed in one, two, and three dimensions. Pressure and velocity oscillations calculated using this procedure are presented for the SSME to show the influence of baffles and absorbers on the burning rate oscillations required to achieve neutral stability. Comparisons are made between the results obtained utilizing 1-D, 2-D, and 3-D assumptions with regards to capturing the physical phenomena of interest and computational requirements.

  13. 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.

  14. 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.

  15. 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.

  16. Effects of 3D Virtual Reality of Plate Tectonics on Fifth Grade Students' Achievement and Attitude toward Science

    ERIC Educational Resources Information Center

    Kim, Paul

    2006-01-01

    This study examines the effects of a teaching method using 3D virtual reality simulations on achievement and attitude toward science. An experiment was conducted with fifth-grade students (N = 41) to examine the effects of 3D simulations, designed to support inquiry-based science curriculum. An ANOVA analysis revealed that the 3D group scored…

  17. 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…

  18. 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

  19. Mackay campus of environmental education and digital cultural construction: the application of 3D virtual reality

    NASA Astrophysics Data System (ADS)

    Chien, Shao-Chi; Chung, Yu-Wei; Lin, Yi-Hsuan; Huang, Jun-Yi; Chang, Jhih-Ting; He, Cai-Ying; Cheng, Yi-Wen

    2012-04-01

    This study uses 3D virtual reality technology to create the "Mackay campus of the environmental education and digital cultural 3D navigation system" for local historical sites in the Tamsui (Hoba) area, in hopes of providing tourism information and navigation through historical sites using a 3D navigation system. We used Auto CAD, Sketch Up, and SpaceEyes 3D software to construct the virtual reality scenes and create the school's historical sites, such as the House of Reverends, the House of Maidens, the Residence of Mackay, and the Education Hall. We used this technology to complete the environmental education and digital cultural Mackay campus . The platform we established can indeed achieve the desired function of providing tourism information and historical site navigation. The interactive multimedia style and the presentation of the information will allow users to obtain a direct information response. In addition to showing the external appearances of buildings, the navigation platform can also allow users to enter the buildings to view lifelike scenes and textual information related to the historical sites. The historical sites are designed according to their actual size, which gives users a more realistic feel. In terms of the navigation route, the navigation system does not force users along a fixed route, but instead allows users to freely control the route they would like to take to view the historical sites on the platform.

  20. Early pregnancy placental bed and fetal vascular volume measurements using 3-D virtual reality.

    PubMed

    Reus, Averil D; Klop-van der Aa, Josine; Rifouna, Maria S; Koning, Anton H J; Exalto, Niek; van der Spek, Peter J; Steegers, Eric A P

    2014-08-01

    In this study, a new 3-D Virtual Reality (3D VR) technique for examining placental and uterine vasculature was investigated. The validity of placental bed vascular volume (PBVV) and fetal vascular volume (FVV) measurements was assessed and associations of PBVV and FVV with embryonic volume, crown-rump length, fetal birth weight and maternal parity were investigated. One hundred thirty-two patients were included in this study, and measurements were performed in 100 patients. Using V-Scope software, 100 3-D Power Doppler data sets of 100 pregnancies at 12 wk of gestation were analyzed with 3D VR in the I-Space Virtual Reality system. Volume measurements were performed with semi-automatic, pre-defined parameters. The inter-observer and intra-observer agreement was excellent with all intra-class correlation coefficients >0.93. PBVVs of multiparous women were significantly larger than the PBVVs of primiparous women (p = 0.008). In this study, no other associations were found. In conclusion, V-Scope offers a reproducible method for measuring PBVV and FVV at 12 wk of gestation, although we are unsure whether the volume measured represents the true volume of the vasculature. Maternal parity influences PBVV. PMID:24798392

  1. Fast extraction of minimal paths in 3D images and applications to virtual endoscopy.

    PubMed

    Deschamps, T; Cohen, L D

    2001-12-01

    The aim of this article is to build trajectories for virtual endoscopy inside 3D medical images, using the most automatic way. Usually the construction of this trajectory is left to the clinician who must define some points on the path manually using three orthogonal views. But for a complex structure such as the colon, those views give little information on the shape of the object of interest. The path construction in 3D images becomes a very tedious task and precise a priori knowledge of the structure is needed to determine a suitable trajectory. We propose a more automatic path tracking method to overcome those drawbacks: we are able to build a path, given only one or two end points and the 3D image as inputs. This work is based on previous work by Cohen and Kimmel [Int. J. Comp. Vis. 24 (1) (1997) 57] for extracting paths in 2D images using Fast Marching algorithm. Our original contribution is twofold. On the first hand, we present a general technical contribution which extends minimal paths to 3D images and gives new improvements of the approach that are relevant in 2D as well as in 3D to extract linear structures in images. It includes techniques to make the path extraction scheme faster and easier, by reducing the user interaction. We also develop a new method to extract a centered path in tubular structures. Synthetic and real medical images are used to illustrate each contribution. On the other hand, we show that our method can be efficiently applied to the problem of finding a centered path in tubular anatomical structures with minimum interactivity, and that this path can be used for virtual endoscopy. Results are shown in various anatomical regions (colon, brain vessels, arteries) with different 3D imaging protocols (CT, MR). PMID:11731307

  2. 3D Face Modeling Using the Multi-Deformable Method

    PubMed Central

    Hwang, Jinkyu; Yu, Sunjin; Kim, Joongrock; Lee, Sangyoun

    2012-01-01

    In this paper, we focus on the problem of the accuracy performance of 3D face modeling techniques using corresponding features in multiple views, which is quite sensitive to feature extraction errors. To solve the problem, we adopt a statistical model-based 3D face modeling approach in a mirror system consisting of two mirrors and a camera. The overall procedure of our 3D facial modeling method has two primary steps: 3D facial shape estimation using a multiple 3D face deformable model and texture mapping using seamless cloning that is a type of gradient-domain blending. To evaluate our method's performance, we generate 3D faces of 30 individuals and then carry out two tests: accuracy test and robustness test. Our method shows not only highly accurate 3D face shape results when compared with the ground truth, but also robustness to feature extraction errors. Moreover, 3D face rendering results intuitively show that our method is more robust to feature extraction errors than other 3D face modeling methods. An additional contribution of our method is that a wide range of face textures can be acquired by the mirror system. By using this texture map, we generate realistic 3D face for individuals at the end of the paper. PMID:23201976

  3. Life in 3D is never flat: 3D models to optimise drug delivery.

    PubMed

    Fitzgerald, Kathleen A; Malhotra, Meenakshi; Curtin, Caroline M; O' Brien, Fergal J; O' Driscoll, Caitriona M

    2015-10-10

    The development of safe, effective and patient-acceptable drug products is an expensive and lengthy process and the risk of failure at different stages of the development life-cycle is high. Improved biopharmaceutical tools which are robust, easy to use and accurately predict the in vivo response are urgently required to help address these issues. In this review the advantages and challenges of in vitro 3D versus 2D cell culture models will be discussed in terms of evaluating new drug products at the pre-clinical development stage. Examples of models with a 3D architecture including scaffolds, cell-derived matrices, multicellular spheroids and biochips will be described. The ability to simulate the microenvironment of tumours and vital organs including the liver, kidney, heart and intestine which have major impact on drug absorption, distribution, metabolism and toxicity will be evaluated. Examples of the application of 3D models including a role in formulation development, pharmacokinetic profiling and toxicity testing will be critically assessed. Although utilisation of 3D cell culture models in the field of drug delivery is still in its infancy, the area is attracting high levels of interest and is likely to become a significant in vitro tool to assist in drug product development thus reducing the requirement for unnecessary animal studies. PMID:26220617

  4. 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.

  5. Assessing the RELAPS-3D Heat Conduction Enclosure Model

    SciTech Connect

    McCann, Larry D.

    2008-09-30

    Three heat conduction problems that have exact solutions are modeled with RELAP5-3D using the conduction enclosure model. These comparisons are designed to be used in the RELAP5-3D development assessment scheduled to be completed in 2009. It is shown that with proper input choices and adequate model detail the exact solutions can be matched. In addition, this analysis identified an error and the required correction in the cylindrical and spherical heat conductor models in RELAP5-3D which will be corrected in a future version of RELAP5-3D.

  6. Web GIS in practice VII: stereoscopic 3-D solutions for online maps and virtual globes

    USGS Publications Warehouse

    Boulos, Maged N.K.; Robinson, Larry R.

    2009-01-01

    Because our pupils are about 6.5 cm apart, each eye views a scene from a different angle and sends a unique image to the visual cortex, which then merges the images from both eyes into a single picture. The slight difference between the right and left images allows the brain to properly perceive the 'third dimension' or depth in a scene (stereopsis). However, when a person views a conventional 2-D (two-dimensional) image representation of a 3-D (three-dimensional) scene on a conventional computer screen, each eye receives essentially the same information. Depth in such cases can only be approximately inferred from visual clues in the image, such as perspective, as only one image is offered to both eyes. The goal of stereoscopic 3-D displays is to project a slightly different image into each eye to achieve a much truer and realistic perception of depth, of different scene planes, and of object relief. This paper presents a brief review of a number of stereoscopic 3-D hardware and software solutions for creating and displaying online maps and virtual globes (such as Google Earth) in "true 3D", with costs ranging from almost free to multi-thousand pounds sterling. A practical account is also given of the experience of the USGS BRD UMESC (United States Geological Survey's Biological Resources Division, Upper Midwest Environmental Sciences Center) in setting up a low-cost, full-colour stereoscopic 3-D system.

  7. 3D resolution enhancement of deep-tissue imaging based on virtual spatial overlap modulation microscopy.

    PubMed

    Su, I-Cheng; Hsu, Kuo-Jen; Shen, Po-Ting; Lin, Yen-Yin; Chu, Shi-Wei

    2016-07-25

    During the last decades, several resolution enhancement methods for optical microscopy beyond diffraction limit have been developed. Nevertheless, those hardware-based techniques typically require strong illumination, and fail to improve resolution in deep tissue. Here we develop a high-speed computational approach, three-dimensional virtual spatial overlap modulation microscopy (3D-vSPOM), which immediately solves the strong-illumination issue. By amplifying only the spatial frequency component corresponding to the un-scattered point-spread-function at focus, plus 3D nonlinear value selection, 3D-vSPOM shows significant resolution enhancement in deep tissue. Since no iteration is required, 3D-vSPOM is much faster than iterative deconvolution. Compared to non-iterative deconvolution, 3D-vSPOM does not need a priori information of point-spread-function at deep tissue, and provides much better resolution enhancement plus greatly improved noise-immune response. This method is ready to be amalgamated with two-photon microscopy or other laser scanning microscopy to enhance deep-tissue resolution. PMID:27464077

  8. Analysis of scalability of high-performance 3D image processing platform for virtual colonoscopy

    NASA Astrophysics Data System (ADS)

    Yoshida, Hiroyuki; Wu, Yin; Cai, Wenli

    2014-03-01

    One of the key challenges in three-dimensional (3D) medical imaging is to enable the fast turn-around time, which is often required for interactive or real-time response. This inevitably requires not only high computational power but also high memory bandwidth due to the massive amount of data that need to be processed. For this purpose, we previously developed a software platform for high-performance 3D medical image processing, called HPC 3D-MIP platform, which employs increasingly available and affordable commodity computing systems such as the multicore, cluster, and cloud computing systems. To achieve scalable high-performance computing, the platform employed size-adaptive, distributable block volumes as a core data structure for efficient parallelization of a wide range of 3D-MIP algorithms, supported task scheduling for efficient load distribution and balancing, and consisted of a layered parallel software libraries that allow image processing applications to share the common functionalities. We evaluated the performance of the HPC 3D-MIP platform by applying it to computationally intensive processes in virtual colonoscopy. Experimental results showed a 12-fold performance improvement on a workstation with 12-core CPUs over the original sequential implementation of the processes, indicating the efficiency of the platform. Analysis of performance scalability based on the Amdahl's law for symmetric multicore chips showed the potential of a high performance scalability of the HPC 3DMIP platform when a larger number of cores is available.

  9. A Voice and Mouse Input Interface for 3D Virtual Environments

    NASA Technical Reports Server (NTRS)

    Kao, David L.; Bryson, Steve T.

    2003-01-01

    There have been many successful stories on how 3D input devices can be fully integrated into an immersive virtual environment. Electromagnetic trackers, optical trackers, gloves, and flying mice are just some of these input devices. Though we can use existing 3D input devices that are commonly used for VR applications, there are several factors that prevent us from choosing these input devices for our applications. One main factor is that most of these tracking devices are not suitable for prolonged use due to human fatigue associated with using them. A second factor is that many of them would occupy additional office space. Another factor is that many of the 3D input devices are expensive due to the unusual hardware that are required. For our VR applications, we want a user interface that would work naturally with standard equipment. In this paper, we demonstrate applications or our proposed muitimodal interface using a 3D dome display. We also show that effective data analysis can be achieved while the scientists view their data rendered inside the dome display and perform user interactions simply using the mouse and voice input. Though the sphere coordinate grid seems to be ideal for interaction using a 3D dome display, we can also use other non-spherical grids as well.

  10. Web GIS in practice VII: stereoscopic 3-D solutions for online maps and virtual globes

    PubMed Central

    Boulos, Maged N Kamel; Robinson, Larry R

    2009-01-01

    Because our pupils are about 6.5 cm apart, each eye views a scene from a different angle and sends a unique image to the visual cortex, which then merges the images from both eyes into a single picture. The slight difference between the right and left images allows the brain to properly perceive the 'third dimension' or depth in a scene (stereopsis). However, when a person views a conventional 2-D (two-dimensional) image representation of a 3-D (three-dimensional) scene on a conventional computer screen, each eye receives essentially the same information. Depth in such cases can only be approximately inferred from visual clues in the image, such as perspective, as only one image is offered to both eyes. The goal of stereoscopic 3-D displays is to project a slightly different image into each eye to achieve a much truer and realistic perception of depth, of different scene planes, and of object relief. This paper presents a brief review of a number of stereoscopic 3-D hardware and software solutions for creating and displaying online maps and virtual globes (such as Google Earth) in "true 3D", with costs ranging from almost free to multi-thousand pounds sterling. A practical account is also given of the experience of the USGS BRD UMESC (United States Geological Survey's Biological Resources Division, Upper Midwest Environmental Sciences Center) in setting up a low-cost, full-colour stereoscopic 3-D system. PMID:19849837

  11. Visualization of 3D Geological Models on Google Earth

    NASA Astrophysics Data System (ADS)

    Choi, Y.; Um, J.; Park, M.

    2013-05-01

    Google Earth combines satellite imagery, aerial photography, thematic maps and various data sets to make a three-dimensional (3D) interactive image of the world. Currently, Google Earth is a popular visualization tool in a variety of fields and plays an increasingly important role not only for private users in daily life, but also for scientists, practitioners, policymakers and stakeholders in research and application. In this study, a method to visualize 3D geological models on Google Earth is presented. COLLAborative Design Activity (COLLADA, an open standard XML schema for establishing interactive 3D applications) was used to represent different 3D geological models such as borehole, fence section, surface-based 3D volume and 3D grid by triangle meshes (a set of triangles connected by their common edges or corners). In addition, we designed Keyhole Markup Language (KML, the XML-based scripting language of Google Earth) codes to import the COLLADA files into the 3D render window of Google Earth. The method was applied to the Grosmont formation in Alberta, Canada. The application showed that the combination of COLLADA and KML enables Google Earth to effectively visualize 3D geological structures and properties.; Visualization of the (a) boreholes, (b) fence sections, (c) 3D volume model and (d) 3D grid model of Grossmont formation on Google Earth

  12. Generating virtual textile composite specimens using statistical data from micro-computed tomography: 3D tow representations

    NASA Astrophysics Data System (ADS)

    Rinaldi, Renaud G.; Blacklock, Matthew; Bale, Hrishikesh; Begley, Matthew R.; Cox, Brian N.

    2012-08-01

    Recent work presented a Monte Carlo algorithm based on Markov Chain operators for generating replicas of textile composite specimens that possess the same statistical characteristics as specimens imaged using high resolution x-ray computed tomography. That work represented the textile reinforcement by one-dimensional tow loci in three-dimensional space, suitable for use in the Binary Model of textile composites. Here analogous algorithms are used to generate solid, three-dimensional (3D) tow representations, to provide geometrical models for more detailed failure analyses. The algorithms for generating 3D models are divided into those that refer to the topology of the textile and those that deal with its geometry. The topological rules carry all the information that distinguishes textiles with different interlacing patterns (weaves, braids, etc.) and provide instructions for resolving interpenetrations or ordering errors among tows. They also simplify writing a single computer program that can accept input data for generic textile cases. The geometrical rules adjust the shape and smoothness of the generated virtual specimens to match data from imaged specimens. The virtual specimen generator is illustrated using data for an angle interlock weave, a common 3D textile architecture.

  13. Comparing a quasi-3D to a full 3D nearshore circulation model: SHORECIRC and ROMS

    NASA Astrophysics Data System (ADS)

    Haas, Kevin A.; Warner, John C.

    Predictions of nearshore and surf zone processes are important for determining coastal circulation, impacts of storms, navigation, and recreational safety. Numerical modeling of these systems facilitates advancements in our understanding of coastal changes and can provide predictive capabilities for resource managers. There exists many nearshore coastal circulation models, however they are mostly limited or typically only applied as depth integrated models. SHORECIRC is an established surf zone circulation model that is quasi-3D to allow the effect of the variability in the vertical structure of the currents while maintaining the computational advantage of a 2DH model. Here we compare SHORECIRC to ROMS, a fully 3D ocean circulation model which now includes a three dimensional formulation for the wave-driven flows. We compare the models with three different test applications for: (i) spectral waves approaching a plane beach with an oblique angle of incidence; (ii) monochromatic waves driving longshore currents in a laboratory basin; and (iii) monochromatic waves on a barred beach with rip channels in a laboratory basin. Results identify that the models are very similar for the depth integrated flows and qualitatively consistent for the vertically varying components. The differences are primarily the result of the vertically varying radiation stress utilized by ROMS and the utilization of long wave theory for the radiation stress formulation in vertical varying momentum balance by SHORECIRC. The quasi-3D model is faster, however the applicability of the fully 3D model allows it to extend over a broader range of processes, temporal, and spatial scales.

  14. Comparing a quasi-3D to a full 3D nearshore circulation model: SHORECIRC and ROMS

    USGS Publications Warehouse

    Haas, K.A.; Warner, J.C.

    2009-01-01

    Predictions of nearshore and surf zone processes are important for determining coastal circulation, impacts of storms, navigation, and recreational safety. Numerical modeling of these systems facilitates advancements in our understanding of coastal changes and can provide predictive capabilities for resource managers. There exists many nearshore coastal circulation models, however they are mostly limited or typically only applied as depth integrated models. SHORECIRC is an established surf zone circulation model that is quasi-3D to allow the effect of the variability in the vertical structure of the currents while maintaining the computational advantage of a 2DH model. Here we compare SHORECIRC to ROMS, a fully 3D ocean circulation model which now includes a three dimensional formulation for the wave-driven flows. We compare the models with three different test applications for: (i) spectral waves approaching a plane beach with an oblique angle of incidence; (ii) monochromatic waves driving longshore currents in a laboratory basin; and (iii) monochromatic waves on a barred beach with rip channels in a laboratory basin. Results identify that the models are very similar for the depth integrated flows and qualitatively consistent for the vertically varying components. The differences are primarily the result of the vertically varying radiation stress utilized by ROMS and the utilization of long wave theory for the radiation stress formulation in vertical varying momentum balance by SHORECIRC. The quasi-3D model is faster, however the applicability of the fully 3D model allows it to extend over a broader range of processes, temporal, and spatial scales. ?? 2008 Elsevier Ltd.

  15. a Fast Method for Measuring the Similarity Between 3d Model and 3d Point Cloud

    NASA Astrophysics Data System (ADS)

    Zhang, Zongliang; Li, Jonathan; Li, Xin; Lin, Yangbin; Zhang, Shanxin; Wang, Cheng

    2016-06-01

    This paper proposes a fast method for measuring the partial Similarity between 3D Model and 3D point Cloud (SimMC). It is crucial to measure SimMC for many point cloud-related applications such as 3D object retrieval and inverse procedural modelling. In our proposed method, the surface area of model and the Distance from Model to point Cloud (DistMC) are exploited as measurements to calculate SimMC. Here, DistMC is defined as the weighted distance of the distances between points sampled from model and point cloud. Similarly, Distance from point Cloud to Model (DistCM) is defined as the average distance of the distances between points in point cloud and model. In order to reduce huge computational burdens brought by calculation of DistCM in some traditional methods, we define SimMC as the ratio of weighted surface area of model to DistMC. Compared to those traditional SimMC measuring methods that are only able to measure global similarity, our method is capable of measuring partial similarity by employing distance-weighted strategy. Moreover, our method is able to be faster than other partial similarity assessment methods. We demonstrate the superiority of our method both on synthetic data and laser scanning data.

  16. A 3D Geometry Model Search Engine to Support Learning

    ERIC Educational Resources Information Center

    Tam, Gary K. L.; Lau, Rynson W. H.; Zhao, Jianmin

    2009-01-01

    Due to the popularity of 3D graphics in animation and games, usage of 3D geometry deformable models increases dramatically. Despite their growing importance, these models are difficult and time consuming to build. A distance learning system for the construction of these models could greatly facilitate students to learn and practice at different…

  17. Evaluation of 3D-Jury on CASP7 models

    PubMed Central

    Kaján, László; Rychlewski, Leszek

    2007-01-01

    Background 3D-Jury, the structure prediction consensus method publicly available in the Meta Server , was evaluated using models gathered in the 7th round of the Critical Assessment of Techniques for Protein Structure Prediction (CASP7). 3D-Jury is an automated expert process that generates protein structure meta-predictions from sets of models obtained from partner servers. Results The performance of 3D-Jury was analysed for three aspects. First, we examined the correlation between the 3D-Jury score and a model quality measure: the number of correctly predicted residues. The 3D-Jury score was shown to correlate significantly with the number of correctly predicted residues, the correlation is good enough to be used for prediction. 3D-Jury was also found to improve upon the competing servers' choice of the best structure model in most cases. The value of the 3D-Jury score as a generic reliability measure was also examined. We found that the 3D-Jury score separates bad models from good models better than the reliability score of the original server in 27 cases and falls short of it in only 5 cases out of a total of 38. We report the release of a new Meta Server feature: instant 3D-Jury scoring of uploaded user models. Conclusion The 3D-Jury score continues to be a good indicator of structural model quality. It also provides a generic reliability score, especially important for models that were not assigned such by the original server. Individual structure modellers can also benefit from the 3D-Jury scoring system by testing their models in the new instant scoring feature available in the Meta Server. PMID:17711571

  18. Avalanche for shape and feature-based virtual screening with 3D alignment.

    PubMed

    Diller, David J; Connell, Nancy D; Welsh, William J

    2015-11-01

    This report introduces a new ligand-based virtual screening tool called Avalanche that incorporates both shape- and feature-based comparison with three-dimensional (3D) alignment between the query molecule and test compounds residing in a chemical database. Avalanche proceeds in two steps. The first step is an extremely rapid shape/feature based comparison which is used to narrow the focus from potentially millions or billions of candidate molecules and conformations to a more manageable number that are then passed to the second step. The second step is a detailed yet still rapid 3D alignment of the remaining candidate conformations to the query conformation. Using the 3D alignment, these remaining candidate conformations are scored, re-ranked and presented to the user as the top hits for further visualization and evaluation. To provide further insight into the method, the results from two prospective virtual screens are presented which show the ability of Avalanche to identify hits from chemical databases that would likely be missed by common substructure-based or fingerprint-based search methods. The Avalanche method is extended to enable patent landscaping, i.e., structural refinements to improve the patentability of hits for deployment in drug discovery campaigns. PMID:26458937

  19. Computational modeling of RNA 3D structures and interactions.

    PubMed

    Dawson, Wayne K; Bujnicki, Janusz M

    2016-04-01

    RNA molecules have key functions in cellular processes beyond being carriers of protein-coding information. These functions are often dependent on the ability to form complex three-dimensional (3D) structures. However, experimental determination of RNA 3D structures is difficult, which has prompted the development of computational methods for structure prediction from sequence. Recent progress in 3D structure modeling of RNA and emerging approaches for predicting RNA interactions with ions, ligands and proteins have been stimulated by successes in protein 3D structure modeling. PMID:26689764

  20. An Automated 3d Indoor Topological Navigation Network Modelling

    NASA Astrophysics Data System (ADS)

    Jamali, A.; Rahman, A. A.; Boguslawski, P.; Gold, C. M.

    2015-10-01

    Indoor navigation is important for various applications such as disaster management and safety analysis. In the last decade, indoor environment has been a focus of wide research; that includes developing techniques for acquiring indoor data (e.g. Terrestrial laser scanning), 3D indoor modelling and 3D indoor navigation models. In this paper, an automated 3D topological indoor network generated from inaccurate 3D building models is proposed. In a normal scenario, 3D indoor navigation network derivation needs accurate 3D models with no errors (e.g. gap, intersect) and two cells (e.g. rooms, corridors) should touch each other to build their connections. The presented 3D modeling of indoor navigation network is based on surveying control points and it is less dependent on the 3D geometrical building model. For reducing time and cost of indoor building data acquisition process, Trimble LaserAce 1000 as surveying instrument is used. The modelling results were validated against an accurate geometry of indoor building environment which was acquired using Trimble M3 total station.

  1. Highway 3D model from image and lidar data

    NASA Astrophysics Data System (ADS)

    Chen, Jinfeng; Chu, Henry; Sun, Xiaoduan

    2014-05-01

    We present a new method of highway 3-D model construction developed based on feature extraction in highway images and LIDAR data. We describe the processing road coordinate data that connect the image frames to the coordinates of the elevation data. Image processing methods are used to extract sky, road, and ground regions as well as significant objects (such as signs and building fronts) in the roadside for the 3D model. LIDAR data are interpolated and processed to extract the road lanes as well as other features such as trees, ditches, and elevated objects to form the 3D model. 3D geometry reasoning is used to match the image features to the 3D model. Results from successive frames are integrated to improve the final model.

  2. Simulation of 3D infrared scenes using random fields model

    NASA Astrophysics Data System (ADS)

    Shao, Xiaopeng; Zhang, Jianqi

    2001-09-01

    Analysis and simulation of smart munitions requires imagery for the munition's sensor to view. The traditional infrared background simulations are always limited in the plane scene studies. A new method is described to synthesize the images in 3D view and with various terrains texture. We develop the random fields model and temperature fields to simulate 3D infrared scenes. Generalized long-correlation (GLC) model, one of random field models, will generate both the 3D terrains skeleton data and the terrains texture in this work. To build the terrain mesh with the random fields, digital elevation models (DEM) are introduced in the paper. And texture mapping technology will perform the task of pasting the texture in the concavo-convex surfaces of the 3D scene. The simulation using random fields model is a very available method to produce 3D infrared scene with great randomicity and reality.

  3. An Automatic Registration Algorithm for 3D Maxillofacial Model

    NASA Astrophysics Data System (ADS)

    Qiu, Luwen; Zhou, Zhongwei; Guo, Jixiang; Lv, Jiancheng

    2016-09-01

    3D image registration aims at aligning two 3D data sets in a common coordinate system, which has been widely used in computer vision, pattern recognition and computer assisted surgery. One challenging problem in 3D registration is that point-wise correspondences between two point sets are often unknown apriori. In this work, we develop an automatic algorithm for 3D maxillofacial models registration including facial surface model and skull model. Our proposed registration algorithm can achieve a good alignment result between partial and whole maxillofacial model in spite of ambiguous matching, which has a potential application in the oral and maxillofacial reparative and reconstructive surgery. The proposed algorithm includes three steps: (1) 3D-SIFT features extraction and FPFH descriptors construction; (2) feature matching using SAC-IA; (3) coarse rigid alignment and refinement by ICP. Experiments on facial surfaces and mandible skull models demonstrate the efficiency and robustness of our algorithm.

  4. 3D pulmonary airway color image reconstruction via shape from shading and virtual bronchoscopy imaging techniques

    NASA Astrophysics Data System (ADS)

    Suter, Melissa; Reinhardt, Joseph M.; Hoffman, Eric A.; McLennan, Geoffrey

    2005-04-01

    The dependence on macro-optical imaging of the human body in the assessment of possible disease is rapidly increasing concurrent with, and as a direct result of, advancements made in medical imaging technologies. Assessing the pulmonary airways through bronchoscopy is performed extensively in clinical practice however remains highly subjective due to limited visualization techniques and the lack of quantitative analyses. The representation of 3D structures in 2D visualization modes, although providing an insight to the structural content of the scene, may in fact skew the perception of the structural form. We have developed two methods for visualizing the optically derived airway mucosal features whilst preserving the structural scene integrity. Shape from shading (SFS) techniques can be used to extract 3D structural information from 2D optical images. The SFS technique presented addresses many limitations previously encountered in conventional techniques resulting in high-resolution 3D color images. The second method presented to combine both color and structural information relies on combined CT and bronchoscopy imaging modalities. External imaging techniques such as CT provide a means of determining the gross structural anatomy of the pulmonary airways, however lack the important optically derived mucosal color. Virtual bronchoscopy is used to provide a direct link between the CT derived structural anatomy and the macro-optically derived mucosal color. Through utilization of a virtual and true bronchoscopy matching technique we are able to directly extract combined structurally sound 3D color segments of the pulmonary airways. Various pulmonary airway diseases are assessed and the resulting combined color and texture results are presented demonstrating the effectiveness of the presented techniques.

  5. Going Virtual… or Not: Development and Testing of a 3D Virtual Astronomy Environment

    NASA Astrophysics Data System (ADS)

    Ruzhitskaya, L.; Speck, A.; Ding, N.; Baldridge, S.; Witzig, S.; Laffey, J.

    2013-04-01

    We present our preliminary results of a pilot study of students' knowledge transfer of an astronomy concept into a new environment. We also share our discoveries on what aspects of a 3D environment students consider being motivational and discouraging for their learning. This study was conducted among 64 non-science major students enrolled in an astronomy laboratory course. During the course, students learned the concept and applications of Kepler's laws using a 2D interactive environment. Later in the semester, the students were placed in a 3D environment in which they were asked to conduct observations and to answers a set of questions pertaining to the Kepler's laws of planetary motion. In this study, we were interested in observing scrutinizing and assessing students' behavior: from choices that they made while creating their avatars (virtual representations) to tools they choose to use, to their navigational patterns, to their levels of discourse in the environment. These helped us to identify what features of the 3D environment our participants found to be helpful and interesting and what tools created unnecessary clutter and distraction. The students' social behavior patterns in the virtual environment together with their answers to the questions helped us to determine how well they understood Kepler's laws, how well they could transfer the concepts to a new situation, and at what point a motivational tool such as a 3D environment becomes a disruption to the constructive learning. Our founding confirmed that students construct deeper knowledge of a concept when they are fully immersed in the environment.

  6. Extending 3D city models with legal information

    NASA Astrophysics Data System (ADS)

    Frank, A. U.; Fuhrmann, T.; Navratil, G.

    2012-10-01

    3D city models represent existing physical objects and their topological and functional relations. In everyday life the rights and responsibilities connected to these objects, primarily legally defined rights and obligations but also other socially and culturally established rights, are of importance. The rights and obligations are defined in various laws and it is often difficult to identify the rules applicable for a certain case. The existing 2D cadastres show civil law rights and obligations and plans to extend them to provide information about public law restrictions for land use are in several countries under way. It is tempting to design extensions to the 3D city models to provide information about legal rights in 3D. The paper analyses the different types of information that are needed to reduce conflicts and to facilitate decisions about land use. We identify the role 3D city models augmented with planning information in 3D can play, but do not advocate a general conversion from 2D to 3D for the legal cadastre. Space is not anisotropic and the up/down dimension is practically very different from the two dimensional plane - this difference must be respected when designing spatial information systems. The conclusions are: (1) continue the current regime for ownership of apartments, which is not ownership of a 3D volume, but co-ownership of a building with exclusive use of some rooms; such exclusive use rights could be shown in a 3D city model; (2) ownership of 3D volumes for complex and unusual building situations can be reported in a 3D city model, but are not required everywhere; (3) indicate restrictions for land use and building in 3D city models, with links to the legal sources.

  7. 3-D Imaging In Virtual Environment: A Scientific Clinical and Teaching Tool

    NASA Technical Reports Server (NTRS)

    Ross, Muriel D.; DeVincenzi, Donald L. (Technical Monitor)

    1996-01-01

    The advent of powerful graphics workstations and computers has led to the advancement of scientific knowledge through three-dimensional (3-D) reconstruction and imaging of biological cells and tissues. The Biocomputation Center at NASA Ames Research Center pioneered the effort to produce an entirely computerized method for reconstruction of objects from serial sections studied in a transmission electron microscope (TEM). The software developed, ROSS (Reconstruction of Serial Sections), is now being distributed to users across the United States through Space Act Agreements. The software is in widely disparate fields such as geology, botany, biology and medicine. In the Biocomputation Center, ROSS serves as the basis for development of virtual environment technologies for scientific and medical use. This report will describe the Virtual Surgery Workstation Project that is ongoing with clinicians at Stanford University Medical Center, and the role of the Visible Human data in the project.

  8. Molecular surface point environments for virtual screening and the elucidation of binding patterns (MOLPRINT 3D).

    PubMed

    Bender, Andreas; Mussa, Hamse Y; Gill, Gurprem S; Glen, Robert C

    2004-12-16

    A novel method (MOLPRINT 3D) for virtual screening and the elucidation of ligand-receptor binding patterns is introduced that is based on environments of molecular surface points. The descriptor uses points relative to the molecular coordinates, thus it is translationally and rotationally invariant. Due to its local nature, conformational variations cause only minor changes in the descriptor. If surface point environments are combined with the Tanimoto coefficient and applied to virtual screening, they achieve retrieval rates comparable to that of two-dimensional (2D) fingerprints. The identification of active structures with minimal 2D similarity ("scaffold hopping") is facilitated. In combination with information-gain-based feature selection and a naive Bayesian classifier, information from multiple molecules can be combined and classification performance can be improved. Selected features are consistent with experimentally determined binding patterns. Examples are given for angiotensin-converting enzyme inhibitors, 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors, and thromboxane A2 antagonists. PMID:15588092

  9. 3-D model-based Bayesian classification

    SciTech Connect

    Soenneland, L.; Tenneboe, P.; Gehrmann, T.; Yrke, O.

    1994-12-31

    The challenging task of the interpreter is to integrate different pieces of information and combine them into an earth model. The sophistication level of this earth model might vary from the simplest geometrical description to the most complex set of reservoir parameters related to the geometrical description. Obviously the sophistication level also depend on the completeness of the available information. The authors describe the interpreter`s task as a mapping between the observation space and the model space. The information available to the interpreter exists in observation space and the task is to infer a model in model-space. It is well-known that this inversion problem is non-unique. Therefore any attempt to find a solution depend son constraints being added in some manner. The solution will obviously depend on which constraints are introduced and it would be desirable to allow the interpreter to modify the constraints in a problem-dependent manner. They will present a probabilistic framework that gives the interpreter the tools to integrate the different types of information and produce constrained solutions. The constraints can be adapted to the problem at hand.

  10. Opportunity Landing Spot Panorama (3-D Model)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The rocky outcrop traversed by the Mars Exploration Rover Opportunity is visible in this three-dimensional model of the rover's landing site. Opportunity has acquired close-up images along the way, and scientists are using the rover's instruments to closely examine portions of interest. The white fragments that look crumpled near the center of the image are portions of the airbags. Distant scenery is displayed on a spherical backdrop or 'billboard' for context. Artifacts near the top rim of the crater are a result of the transition between the three-dimensional model and the billboard. Portions of the terrain model lacking sufficient data appear as blank spaces or gaps, colored reddish-brown for better viewing. This image was generated using special software from NASA's Ames Research Center and a mosaic of images taken by the rover's panoramic camera.

    [figure removed for brevity, see original site] Click on image for larger view

    The rocky outcrop traversed by the Mars Exploration Rover Opportunity is visible in this zoomed-in portion of a three-dimensional model of the rover's landing site. Opportunity has acquired close-up images along the way, and scientists are using the rover's instruments to closely examine portions of interest. The white fragments that look crumpled near the center of the image are portions of the airbags. Distant scenery is displayed on a spherical backdrop or 'billboard' for context. Artifacts near the top rim of the crater are a result of the transition between the three-dimensional model and the billboard. Portions of the terrain model lacking sufficient data appear as blank spaces or gaps, colored reddish-brown for better viewing. This image was generated using special software from NASA's Ames Research Center and a mosaic of images taken by the rover's panoramic camera.

  11. Venusian Applications of 3D Convection Modeling

    NASA Technical Reports Server (NTRS)

    Bonaccorso, Timary Annie

    2011-01-01

    This study models mantle convection on Venus using the 'cubed sphere' code OEDIPUS, which models one-sixth of the planet in spherical geometry. We are attempting to balance internal heating, bottom mantle viscosity, and temperature difference across Venus' mantle, in order to create a realistic model that matches with current planetary observations. We also have begun to run both lower and upper mantle simulations to determine whether layered (as opposed to whole-mantle) convection might produce more efficient heat transfer, as well as to model coronae formation in the upper mantle. Upper mantle simulations are completed using OEDIPUS' Cartesian counterpart, JOCASTA. This summer's central question has been how to define a mantle plume. Traditionally, we have defined a hot plume the region with temperature at or above 40% of the difference between the maximum and horizontally averaged temperature, and a cold plume as the region with 40% of the difference between the minimum and average temperature. For less viscous cases (1020 Pa?s), the plumes generated by that definition lacked vigor, displaying buoyancies 1/100th of those found in previous, higher viscosity simulations (1021 Pa?s). As the mantle plumes with large buoyancy flux are most likely to produce topographic uplift and volcanism, the low viscosity cases' plumes may not produce observable deformation. In an effort to eliminate the smallest plumes, we experimented with different lower bound parameters and temperature percentages.

  12. RELAP5-3D Compressor Model

    SciTech Connect

    James E. Fisher; Cliff B. Davis; Walter L. Weaver

    2005-06-01

    A compressor model has been implemented in the RELAP5-3D© code. The model is similar to that of the existing pump model, and performs the same function on a gas as the pump performs on a single-phase or two-phase fluid. The compressor component consists of an inlet junction and a control volume, and optionally, an outlet junction. This feature permits cascading compressor components in series. The equations describing the physics of the compressor are derived from first principles. These equations are used to obtain the head, the torque, and the energy dissipation. Compressor performance is specified using a map, specific to the design of the machine, in terms of the ratio of outlet-to-inlet total (or stagnation) pressure and adiabatic efficiency as functions of rotational velocity and flow rate. The input quantities are specified in terms of dimensionless variables, which are corrected to stagnation density and stagnation sound speed. A small correction was formulated for the input of efficiency to account for the error introduced by assumption of constant density when integrating the momentum equation. Comparison of the results of steady-state operation of the compressor model to those of the MIT design calculation showed excellent agreement for both pressure ratio and power.

  13. Why 3D? The Need for Solution Based Modeling in a National Geoscience Organization.

    NASA Astrophysics Data System (ADS)

    Terrington, Ricky; Napier, Bruce; Howard, Andy; Ford, Jon; Hatton, William

    2008-05-01

    In recent years national geoscience organizations have increasingly utilized 3D model data as an output to the stakeholder community. Advances in both software and hardware have led to an increasing use of 3D depictions of geoscience data alongside the standard 2D data formats such as maps and GIS data. By characterizing geoscience data in 3D, knowledge transfer between geoscientists and stakeholders is improved as the mindset and thought processes are communicated more effectively in a 3D model than in a 2D flat file format. 3D models allow the user to understand the conceptual basis of the 2D data and aids the decision making process at local, regional and national scales. Some of these issues include foundation and engineering conditions, ground water vulnerability, aquifer recharge and flow, and resource extraction and storage. The British Geological Survey has established a mechanism and infrastructure through the Digital Geoscience Spatial Model Programme (DGSM) to produce these types of 3D geoscience outputs. This cyber-infrastructure not only allows good data and information management, it enables geoscientists to capture their know-how and implicit and tacit knowledge for their 3D interpretations. A user of this data will then have access to value-added information for the 3D dataset including the knowledge, approach, inferences, uncertainty, wider context and best practice acquired during the 3D interpretation. To complement this cyber-infrastructure, an immersive 3D Visualization Facility was constructed at the British Geological Survey offices in Keyworth, Nottingham and Edinburgh. These custom built facilities allow stereo projection of geoscience data, immersing the users and stakeholders in a wealth of 3D geological data. Successful uses of these facilities include collaborative 3D modeling, demonstrations to public stakeholders and Virtual Field Mapping Reconnaissance.

  14. NoSQL Based 3D City Model Management System

    NASA Astrophysics Data System (ADS)

    Mao, B.; Harrie, L.; Cao, J.; Wu, Z.; Shen, J.

    2014-04-01

    To manage increasingly complicated 3D city models, a framework based on NoSQL database is proposed in this paper. The framework supports import and export of 3D city model according to international standards such as CityGML, KML/COLLADA and X3D. We also suggest and implement 3D model analysis and visualization in the framework. For city model analysis, 3D geometry data and semantic information (such as name, height, area, price and so on) are stored and processed separately. We use a Map-Reduce method to deal with the 3D geometry data since it is more complex, while the semantic analysis is mainly based on database query operation. For visualization, a multiple 3D city representation structure CityTree is implemented within the framework to support dynamic LODs based on user viewpoint. Also, the proposed framework is easily extensible and supports geoindexes to speed up the querying. Our experimental results show that the proposed 3D city management system can efficiently fulfil the analysis and visualization requirements.

  15. Modelling Polymer Deformation during 3D Printing

    NASA Astrophysics Data System (ADS)

    McIlroy, Claire; Olmsted, Peter

    Three-dimensional printing has the potential to transform manufacturing processes, yet improving the strength of printed parts, to equal that of traditionally-manufactured parts, remains an underlying issue. The fused deposition modelling technique involves melting a thermoplastic, followed by layer-by-layer extrusion to fabricate an object. The key to ensuring strength at the weld between layers is successful inter-diffusion. However, prior to welding, both the extrusion process and the cooling temperature profile can significantly deform the polymer micro-structure and, consequently, how well the polymers are able to ``re-entangle'' across the weld. In particular, polymer alignment in the flow can cause de-bonding of the layers and create defects. We have developed a simple model of the non-isothermal extrusion process to explore the effects that typical printing conditions and material rheology have on the conformation of a polymer melt. In particular, we incorporate both stretch and orientation using the Rolie-Poly constitutive equation to examine the melt structure as it flows through the nozzle, the subsequent alignment with the build plate and the resulting deformation due to the fixed nozzle height, which is typically less than the nozzle radius.

  16. Kongsfjorden-MIKE 3D model

    NASA Astrophysics Data System (ADS)

    Przyborska, Anna; Kosecki, Szymon; Jakacki, Jaromir

    2014-05-01

    Kongsfjorden is a West Svalbard fjord with a surface area of about 210 km2. It is obvious that the depths of the outer and central basins are influenced by the open sea, under influence of West Spitsbergen Current (WSC), which curry out warm Atlantic water and cold East Spitsbergen Current, while the shallower, inner basin has a large glacial outflow and its maximum depths do not exceed 100 m. Freshwater stored in Spitsbergen glaciers have strong influence on local hydrology and physical fjord conditions. Both, local and shelf conditions have impact on state of the fjord. External forces like tides, velocities at the boundary and atmospheric forces together with sources of cold and dens fresh water in the fjords will give reliable representation of physical conditions in Kongsfjorden. Modeling could help to solve this problem and we have hope that we find answer which one is the most important for local conditions in fjord. Calculations of balances between cold fresh water and warm and salt will provide additional information that could help to answer the main question of the GAME (Growing of the Arctic Marine Ecosystem) project - what is the reaction of physically controlled Arctic marine ecosystem to temperature rise.

  17. 3D PIC Modeling of Microcavity Discharge

    NASA Astrophysics Data System (ADS)

    Hopkins, Matthew; Manginell, Ronald; Moore, Christopher; Yee, Benjamin; Moorman, Matthew

    2015-09-01

    We present a number of techniques and challenges in simulating the transient behavior of a microcavity discharge. Our microcavities are typically cylindrical with diameters approximately 50 - 100 μm, heights of 50 - 200 μm, pressure near atmospheric, and operate at a few hundred volts. We employ a fully kinetic simulation methodology, the Particle-in-Cell (PIC) method, with interparticle collisions handled via methods based on direct simulation Monte Carlo (DSMC). In particular, we explicitly include kinetic electrons. Some of the challenges we encounter include variations in number densities, external circuit coupling, and time step resolution constraints. By employing dynamic particle weighting (particle weights vary over time by species and location) we can mitigate some of the challenges modeling systems with 107 variations in number densities. Smoothing mechanisms have been used to attempt to mitigate external circuit response. We perform our simulations on hundreds or thousands of processing cores to accommodate the computational work inherent in using relatively small time step sizes (e.g., 50 fs for a 100 ns calculation). In addition, particle weighting issues inherent to three-dimensional low temperature plasma systems will be mentioned. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's NNSA under Contract DE-AC04-94AL85000.

  18. A video, text, and speech-driven realistic 3-d virtual head for human-machine interface.

    PubMed

    Yu, Jun; Wang, Zeng-Fu

    2015-05-01

    A multiple inputs-driven realistic facial animation system based on 3-D virtual head for human-machine interface is proposed. The system can be driven independently by video, text, and speech, thus can interact with humans through diverse interfaces. The combination of parameterized model and muscular model is used to obtain a tradeoff between computational efficiency and high realism of 3-D facial animation. The online appearance model is used to track 3-D facial motion from video in the framework of particle filtering, and multiple measurements, i.e., pixel color value of input image and Gabor wavelet coefficient of illumination ratio image, are infused to reduce the influence of lighting and person dependence for the construction of online appearance model. The tri-phone model is used to reduce the computational consumption of visual co-articulation in speech synchronized viseme synthesis without sacrificing any performance. The objective and subjective experiments show that the system is suitable for human-machine interaction. PMID:25122851

  19. The 3D model: explaining densification and deformation mechanisms by using 3D parameter plots.

    PubMed

    Picker, Katharina M

    2004-04-01

    The aim of the study was to analyze very differently deforming materials using 3D parameter plots and consequently to gain deeper insights into the densification and deformation process described with the 3D model in order to define an ideal tableting excipient. The excipients used were dicalcium phosphate dihydrate (DCPD), sodium chloride (NaCl), microcrystalline cellulose (MCC), xylitol, mannitol, alpha-lactose monohydrate, maltose, hydroxypropyl methylcellulose (HPMC), sodium carboxymethylcellulose (NaCMC), cellulose acetate (CAC), maize starch, potato starch, pregelatinized starch, and maltodextrine. All of the materials were tableted to graded maximum relative densities (rhorel, max) using an eccentric tableting machine. The data which resulted, namely force, displacement, and time, were analyzed by the application of 3D modeling. Different particle size fractions of DCPD, CAC, and MCC were analyzed in addition. Brittle deforming materials such as DCPD exhibited a completely different 3D parameter plot, with low time plasticity, d, and low pressure plasticity, e, and a strong decrease in omega values when densification increased, in contrast to the plastically deforming MCC, which had much higher d, e, and omega values. e and omega values changed only slightly when densification increased for MCC. NaCl showed less of a decrease in omega values than DCPD did, and the d and e values were between those of MCC and DCPD. The sugar alcohols, xylitol and mannitol, behaved in a similar fashion to sodium chloride. This is also valid for the crystalline sugars, alpha-lactose monohydrate, and maltose. However, the sugars are more brittle than the sugar alcohols. The cellulose derivatives, HPMC, NaCMC, and CAC, are as plastic as MCC, however, their elasticity depends on substitution indicated by lower (more elastic) or higher (less elastic) omega values. The native starches, maize starch and potato starch, are very elastic, and pregelatinized starch and maltodextrine are

  20. Scalable, High-performance 3D Imaging Software Platform: System Architecture and Application to Virtual Colonoscopy

    PubMed Central

    Yoshida, Hiroyuki; Wu, Yin; Cai, Wenli; Brett, Bevin

    2013-01-01

    One of the key challenges in three-dimensional (3D) medical imaging is to enable the fast turn-around time, which is often required for interactive or real-time response. This inevitably requires not only high computational power but also high memory bandwidth due to the massive amount of data that need to be processed. In this work, we have developed a software platform that is designed to support high-performance 3D medical image processing for a wide range of applications using increasingly available and affordable commodity computing systems: multi-core, clusters, and cloud computing systems. To achieve scalable, high-performance computing, our platform (1) employs size-adaptive, distributable block volumes as a core data structure for efficient parallelization of a wide range of 3D image processing algorithms; (2) supports task scheduling for efficient load distribution and balancing; and (3) consists of a layered parallel software libraries that allow a wide range of medical applications to share the same functionalities. We evaluated the performance of our platform by applying it to an electronic cleansing system in virtual colonoscopy, with initial experimental results showing a 10 times performance improvement on an 8-core workstation over the original sequential implementation of the system. PMID:23366803

  1. Towards a 3d Based Platform for Cultural Heritage Site Survey and Virtual Exploration

    NASA Astrophysics Data System (ADS)

    Seinturier, J.; Riedinger, C.; Mahiddine, A.; Peloso, D.; Boï, J.-M.; Merad, D.; Drap, P.

    2013-07-01

    This paper present a 3D platform that enables to make both cultural heritage site survey and its virtual exploration. It provides a single and easy way to use framework for merging multi scaled 3D measurements based on photogrammetry, documentation produced by experts and the knowledge of involved domains leaving the experts able to extract and choose the relevant information to produce the final survey. Taking into account the interpretation of the real world during the process of archaeological surveys is in fact the main goal of a survey. New advances in photogrammetry and the capability to produce dense 3D point clouds do not solve the problem of surveys. New opportunities for 3D representation are now available and we must to use them and find new ways to link geometry and knowledge. The new platform is able to efficiently manage and process large 3D data (points set, meshes) thanks to the implementation of space partition methods coming from the state of the art such as octrees and kd-trees and thus can interact with dense point clouds (thousands to millions of points) in real time. The semantisation of raw 3D data relies on geometric algorithms such as geodetic path computation, surface extraction from dense points cloud and geometrical primitive optimization. The platform provide an interface that enables expert to describe geometric representations of interesting objects like ashlar blocs, stratigraphic units or generic items (contour, lines, … ) directly onto the 3D representation of the site and without explicit links to underlying algorithms. The platform provide two ways for describing geometric representation. If oriented photographs are available, the expert can draw geometry on a photograph and the system computes its 3D representation by projection on the underlying mesh or the points cloud. If photographs are not available or if the expert wants to only use the 3D representation then he can simply draw objects shape on it. When 3D

  2. Instructors' Perceptions of Three-Dimensional (3D) Virtual Worlds: Instructional Use, Implementation and Benefits for Adult Learners

    ERIC Educational Resources Information Center

    Stone, Sophia Jeffries

    2009-01-01

    The purpose of this dissertation research study was to explore instructors' perceptions of the educational application of three-dimensional (3D) virtual worlds in a variety of academic discipline areas and to assess the strengths and limitations this virtual environment presents for teaching adult learners. The guiding research question for this…

  3. Using a Quest in a 3D Virtual Environment for Student Interaction and Vocabulary Acquisition in Foreign Language Learning

    ERIC Educational Resources Information Center

    Kastoudi, Denise

    2011-01-01

    The gaming and interactional nature of the virtual environment of Second Life offers opportunities for language learning beyond the traditional pedagogy. This study case examined the potential of 3D virtual quest games to enhance vocabulary acquisition through interaction, negotiation of meaning and noticing. Four adult students of English at…

  4. Mixed reality orthognathic surgical simulation by entity model manipulation and 3D-image display

    NASA Astrophysics Data System (ADS)

    Shimonagayoshi, Tatsunari; Aoki, Yoshimitsu; Fushima, Kenji; Kobayashi, Masaru

    2005-12-01

    In orthognathic surgery, the framing of 3D-surgical planning that considers the balance between the front and back positions and the symmetry of the jawbone, as well as the dental occlusion of teeth, is essential. In this study, a support system for orthodontic surgery to visualize the changes in the mandible and the occlusal condition and to determine the optimum position in mandibular osteotomy has been developed. By integrating the operating portion of a tooth model that is to determine the optimum occlusal position by manipulating the entity tooth model and the 3D-CT skeletal images (3D image display portion) that are simultaneously displayed in real-time, the determination of the mandibular position and posture in which the improvement of skeletal morphology and occlusal condition is considered, is possible. The realistic operation of the entity model and the virtual 3D image display enabled the construction of a surgical simulation system that involves augmented reality.

  5. 3D-model building of the jaw impression

    NASA Astrophysics Data System (ADS)

    Ahmed, Moumen T.; Yamany, Sameh M.; Hemayed, Elsayed E.; Farag, Aly A.

    1997-03-01

    A novel approach is proposed to obtain a record of the patient's occlusion using computer vision. Data acquisition is obtained using intra-oral video cameras. The technique utilizes shape from shading to extract 3D information from 2D views of the jaw, and a novel technique for 3D data registration using genetic algorithms. The resulting 3D model can be used for diagnosis, treatment planning, and implant purposes. The overall purpose of this research is to develop a model-based vision system for orthodontics to replace traditional approaches. This system will be flexible, accurate, and will reduce the cost of orthodontic treatments.

  6. 3D model-based still image object categorization

    NASA Astrophysics Data System (ADS)

    Petre, Raluca-Diana; Zaharia, Titus

    2011-09-01

    This paper proposes a novel recognition scheme algorithm for semantic labeling of 2D object present in still images. The principle consists of matching unknown 2D objects with categorized 3D models in order to infer the semantics of the 3D object to the image. We tested our new recognition framework by using the MPEG-7 and Princeton 3D model databases in order to label unknown images randomly selected from the web. Results obtained show promising performances, with recognition rate up to 84%, which opens interesting perspectives in terms of semantic metadata extraction from still images/videos.

  7. Summary on Several Key Techniques in 3D Geological Modeling

    PubMed Central

    2014-01-01

    Several key techniques in 3D geological modeling including planar mesh generation, spatial interpolation, and surface intersection are summarized in this paper. Note that these techniques are generic and widely used in various applications but play a key role in 3D geological modeling. There are two essential procedures in 3D geological modeling: the first is the simulation of geological interfaces using geometric surfaces and the second is the building of geological objects by means of various geometric computations such as the intersection of surfaces. Discrete geometric surfaces that represent geological interfaces can be generated by creating planar meshes first and then spatially interpolating; those surfaces intersect and then form volumes that represent three-dimensional geological objects such as rock bodies. In this paper, the most commonly used algorithms of the key techniques in 3D geological modeling are summarized. PMID:24772029

  8. A Shell/3D Modeling Technique for the Analysis of Delaminated Composite Laminates

    NASA Technical Reports Server (NTRS)

    Krueger, Ronald; OBrien, T. Kevin

    2000-01-01

    A shell/3D modeling technique was developed for which a local solid finite element model is used only in the immediate vicinity of the delamination front. The goal was to combine the accuracy of the full three-dimensional solution with the computational efficiency of a shell finite element model. Multi-point constraints provided a kinematically compatible interface between the local 3D model and the global structural model which has been meshed with shell finite elements. Double Cantilever Beam, End Notched Flexure, and Single Leg Bending specimens were analyzed first using full 3D finite element models to obtain reference solutions. Mixed mode strain energy release rate distributions were computed using the virtual crack closure technique. The analyses were repeated using the shell/3D technique to study the feasibility for pure mode I, mode II and mixed mode I/II cases. Specimens with a unidirectional layup and with a multidirectional layup were simulated. For a local 3D model, extending to a minimum of about three specimen thicknesses on either side of the delamination front, the results were in good agreement with mixed mode strain energy release rates obtained from computations where the entire specimen had been modeled with solid elements. For large built-up composite structures the shell/3D modeling technique offers a great potential for reducing the model size, since only a relatively small section in the vicinity of the delamination front needs to be modeled with solid elements.

  9. Formal representation of 3D structural geological models

    NASA Astrophysics Data System (ADS)

    Wang, Zhangang; Qu, Honggang; Wu, Zixing; Yang, Hongjun; Du, Qunle

    2016-05-01

    The development and widespread application of geological modeling methods has increased demands for the integration and sharing services of three dimensional (3D) geological data. However, theoretical research in the field of geological information sciences is limited despite the widespread use of Geographic Information Systems (GIS) in geology. In particular, fundamental research on the formal representations and standardized spatial descriptions of 3D structural models is required. This is necessary for accurate understanding and further applications of geological data in 3D space. In this paper, we propose a formal representation method for 3D structural models using the theory of point set topology, which produces a mathematical definition for the major types of geological objects. The spatial relationships between geologic boundaries, structures, and units are explained in detail using the 9-intersection model. Reasonable conditions for describing the topological space of 3D structural models are also provided. The results from this study can be used as potential support for the standardized representation and spatial quality evaluation of 3D structural models, as well as for specific needs related to model-based management, query, and analysis.

  10. 3D Modeling from Photos Given Topological Information.

    PubMed

    Kim, Young Min; Cho, Junghyun; Ahn, Sang Chul

    2016-09-01

    Reconstructing 3D models given a single-view 2D information is inherently an ill-posed problem and requires additional information such as shape prior or user input.We introduce a method to generate multiple 3D models of a particular category given corresponding photographs when the topological information is known. While there is a wide range of shapes for an object of a particular category, the basic topology usually remains constant.In consequence, the topological prior needs to be provided only once for each category and can be easily acquired by consulting an existing database of 3D models or by user input. The input of topological description is only connectivity information between parts; this is in contrast to previous approaches that have required users to interactively mark individual parts. Given the silhouette of an object and the topology, our system automatically finds a skeleton and generates a textured 3D model by jointly fitting multiple parts. The proposed method, therefore, opens the possibility of generating a large number of 3D models by consulting a massive number of photographs. We demonstrate examples of the topological prior and reconstructed 3D models using photos. PMID:26661474

  11. 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.

  12. Performance Evaluation of 3d Modeling Software for Uav Photogrammetry

    NASA Astrophysics Data System (ADS)

    Yanagi, H.; Chikatsu, H.

    2016-06-01

    UAV (Unmanned Aerial Vehicle) photogrammetry, which combines UAV and freely available internet-based 3D modeling software, is widely used as a low-cost and user-friendly photogrammetry technique in the fields such as remote sensing and geosciences. In UAV photogrammetry, only the platform used in conventional aerial photogrammetry is changed. Consequently, 3D modeling software contributes significantly to its expansion. However, the algorithms of the 3D modelling software are black box algorithms. As a result, only a few studies have been able to evaluate their accuracy using 3D coordinate check points. With this motive, Smart3DCapture and Pix4Dmapper were downloaded from the Internet and commercial software PhotoScan was also employed; investigations were performed in this paper using check points and images obtained from UAV.

  13. Tissue-plastinated vs. celloidin-embedded large serial sections in video, analog and digital photographic on-screen reproduction: a preliminary step to exact virtual 3D modelling, exemplified in the normal midface and cleft-lip and palate

    PubMed Central

    Landes, Constantin A; Weichert, Frank; Geis, Philipp; Wernstedt, Katrin; Wilde, Anja; Fritsch, Helga; Wagner, Mathias

    2005-01-01

    This study analyses tissue-plastinated vs. celloidin-embedded large serial sections, their inherent artefacts and aptitude with common video, analog or digital photographic on-screen reproduction. Subsequent virtual 3D microanatomical reconstruction will increase our knowledge of normal and pathological microanatomy for cleft-lip-palate (clp) reconstructive surgery. Of 18 fetal (six clp, 12 control) specimens, six randomized specimens (two clp) were BiodurE12-plastinated, sawn, burnished 90 µm thick transversely (five) or frontally (one), stained with azureII/methylene blue, and counterstained with basic-fuchsin (TP-AMF). Twelve remaining specimens (four clp) were celloidin-embedded, microtome-sectioned 75 µm thick transversely (ten) or frontally (two), and stained with haematoxylin–eosin (CE-HE). Computed-planimetry gauged artefacts, structure differentiation was compared with light microscopy on video, analog and digital photography. Total artefact was 0.9% (TP-AMF) and 2.1% (CE-HE); TP-AMF showed higher colour contrast, gamut and luminance, and CE-HE more red contrast, saturation and hue (P < 0.4). All (100%) structures of interest were light microscopically discerned, 83% on video, 76% on analog photography and 98% in digital photography. Computed image analysis assessed the greatest colour contrast, gamut, luminance and saturation on video; the most detailed, colour-balanced and sharpest images were obatined with digital photography (P < 0.02). TP-AMF retained spatial oversight, covered the entire area of interest and should be combined in different specimens with CE-HE which enables more refined muscle fibre reproduction. Digital photography is preferred for on-screen analysis. PMID:16050904

  14. Automatic Texture Mapping of Architectural and Archaeological 3d Models

    NASA Astrophysics Data System (ADS)

    Kersten, T. P.; Stallmann, D.

    2012-07-01

    Today, detailed, complete and exact 3D models with photo-realistic textures are increasingly demanded for numerous applications in architecture and archaeology. Manual texture mapping of 3D models by digital photographs with software packages, such as Maxon Cinema 4D, Autodesk 3Ds Max or Maya, still requires a complex and time-consuming workflow. So, procedures for automatic texture mapping of 3D models are in demand. In this paper two automatic procedures are presented. The first procedure generates 3D surface models with textures by web services, while the second procedure textures already existing 3D models with the software tmapper. The program tmapper is based on the Multi Layer 3D image (ML3DImage) algorithm and developed in the programming language C++. The studies showing that the visibility analysis using the ML3DImage algorithm is not sufficient to obtain acceptable results of automatic texture mapping. To overcome the visibility problem the Point Cloud Painter algorithm in combination with the Z-buffer-procedure will be applied in the future.

  15. The Complete Virtual 3d Reconstruction of the East Pediment of the Temple of ZEUS at Olympia

    NASA Astrophysics Data System (ADS)

    Patay-Horváth, A.

    2011-09-01

    The arrangement of the five central figures of the east pediment of the temple of Zeus at Olympia has been the subject of scholarly debates since the discovery of the fragments more than a century ago. In theory, there are four substantially different arrangements, all of which have already been selected by certain scholars for various aesthetic, technical and other considerations. The present project tries to approach this controversy in a new way, by producing a virtual 3D reconstruction of the group. Digital models of the statues were produced by scanning the original fragments and by reconstructing them virtually. For this purpose an innovative new software (Leonar3Do) has also been employed. The virtual model of the pediment surrounding the sculptures was prepared on the basis of the latest architectural studies and afterwards the reconstructed models were inserted in this frame, in order to test the technical feasibility and aesthetic effects the four possible arrangements. The paper gives an overview of the entire work and presents the final results suggesting that two arrangements can be ruled out due to the limited space available in the pediment.

  16. Using a 3D Virtual Supermarket to Measure Food Purchase Behavior: A Validation Study

    PubMed Central

    Jiang, Yannan; Steenhuis, Ingrid Hendrika Margaretha; Ni Mhurchu, Cliona

    2015-01-01

    Background There is increasing recognition that supermarkets are an important environment for health-promoting interventions such as fiscal food policies or front-of-pack nutrition labeling. However, due to the complexities of undertaking such research in the real world, well-designed randomized controlled trials on these kinds of interventions are lacking. The Virtual Supermarket is a 3-dimensional computerized research environment designed to enable experimental studies in a supermarket setting without the complexity or costs normally associated with undertaking such research. Objective The primary objective was to validate the Virtual Supermarket by comparing virtual and real-life food purchasing behavior. A secondary objective was to obtain participant feedback on perceived sense of “presence” (the subjective experience of being in one place or environment even if physically located in another) in the Virtual Supermarket. Methods Eligible main household shoppers (New Zealand adults aged ≥18 years) were asked to conduct 3 shopping occasions in the Virtual Supermarket over 3 consecutive weeks, complete the validated Presence Questionnaire Items Stems, and collect their real supermarket grocery till receipts for that same period. Proportional expenditure (NZ$) and the proportion of products purchased over 18 major food groups were compared between the virtual and real supermarkets. Data were analyzed using repeated measures mixed models. Results A total of 123 participants consented to take part in the study. In total, 69.9% (86/123) completed 1 shop in the Virtual Supermarket, 64.2% (79/123) completed 2 shops, 60.2% (74/123) completed 3 shops, and 48.8% (60/123) returned their real supermarket till receipts. The 4 food groups with the highest relative expenditures were the same for the virtual and real supermarkets: fresh fruit and vegetables (virtual estimate: 14.3%; real: 17.4%), bread and bakery (virtual: 10.0%; real: 8.2%), dairy (virtual: 19.1%; real

  17. Gis-Based Smart Cartography Using 3d Modeling

    NASA Astrophysics Data System (ADS)

    Malinverni, E. S.; Tassetti, A. N.

    2013-08-01

    3D City Models have evolved to be important tools for urban decision processes and information systems, especially in planning, simulation, analysis, documentation and heritage management. On the other hand existing and in use numerical cartography is often not suitable to be used in GIS because not geometrically and topologically correctly structured. The research aim is to 3D structure and organize a numeric cartography for GIS and turn it into CityGML standardized features. The work is framed around a first phase of methodological analysis aimed to underline which existing standard (like ISO and OGC rules) can be used to improve the quality requirement of a cartographic structure. Subsequently, from this technical specifics, it has been investigated the translation in formal contents, using an owner interchange software (SketchUp), to support some guide lines implementations to generate a GIS3D structured in GML3. It has been therefore predisposed a test three-dimensional numerical cartography (scale 1:500, generated from range data captured by 3D laser scanner), tested on its quality according to the previous standard and edited when and where necessary. Cad files and shapefiles are converted into a final 3D model (Google SketchUp model) and then exported into a 3D city model (CityGML LoD1/LoD2). The GIS3D structure has been managed in a GIS environment to run further spatial analysis and energy performance estimate, not achievable in a 2D environment. In particular geometrical building parameters (footprint, volume etc.) are computed and building envelop thermal characteristics are derived from. Lastly, a simulation is carried out to deal with asbestos and home renovating charges and show how the built 3D city model can support municipal managers with risk diagnosis of the present situation and development of strategies for a sustainable redevelop.

  18. 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.

  19. Combined registration of 3D tibia and femur implant models in 3D magnetic resonance images

    NASA Astrophysics Data System (ADS)

    Englmeier, Karl-Hans; Siebert, Markus; von Eisenhart-Rothe, Ruediger; Graichen, Heiko

    2008-03-01

    The most frequent reasons for revision of total knee arthroplasty are loosening and abnormal axial alignment leading to an unphysiological kinematic of the knee implant. To get an idea about the postoperative kinematic of the implant, it is essential to determine the position and orientation of the tibial and femoral prosthesis. Therefore we developed a registration method for fitting 3D CAD-models of knee joint prostheses into an 3D MR image. This rigid registration is the basis for a quantitative analysis of the kinematics of knee implants. Firstly the surface data of the prostheses models are converted into a voxel representation; a recursive algorithm determines all boundary voxels of the original triangular surface data. Secondly an initial preconfiguration of the implants by the user is still necessary for the following step: The user has to perform a rough preconfiguration of both remaining prostheses models, so that the fine matching process gets a reasonable starting point. After that an automated gradient-based fine matching process determines the best absolute position and orientation: This iterative process changes all 6 parameters (3 rotational- and 3 translational parameters) of a model by a minimal amount until a maximum value of the matching function is reached. To examine the spread of the final solutions of the registration, the interobserver variability was measured in a group of testers. This variability, calculated by the relative standard deviation, improved from about 50% (pure manual registration) to 0.5% (rough manual preconfiguration and subsequent fine registration with the automatic fine matching process).

  20. 3D Bioprinting of Tissue/Organ Models.

    PubMed

    Pati, Falguni; Gantelius, Jesper; Svahn, Helene Andersson

    2016-04-01

    In vitro tissue/organ models are useful platforms that can facilitate systematic, repetitive, and quantitative investigations of drugs/chemicals. The primary objective when developing tissue/organ models is to reproduce physiologically relevant functions that typically require complex culture systems. Bioprinting offers exciting prospects for constructing 3D tissue/organ models, as it enables the reproducible, automated production of complex living tissues. Bioprinted tissues/organs may prove useful for screening novel compounds or predicting toxicity, as the spatial and chemical complexity inherent to native tissues/organs can be recreated. In this Review, we highlight the importance of developing 3D in vitro tissue/organ models by 3D bioprinting techniques, characterization of these models for evaluating their resemblance to native tissue, and their application in the prioritization of lead candidates, toxicity testing, and as disease/tumor models. PMID:26895542

  1. 3D web visualization of huge CityGML models

    NASA Astrophysics Data System (ADS)

    Prandi, F.; Devigili, F.; Soave, M.; Di Staso, U.; De Amicis, R.

    2015-08-01

    Nowadays, rapid technological development into acquiring geo-spatial information; joined to the capabilities to process these data in a relative short period of time, allows the generation of detailed 3D textured city models that will become an essential part of the modern city information infrastructure (Spatial Data Infrastructure) and, can be used to integrate various data from different sources for public accessible visualisation and many other applications. One of the main bottlenecks, which at the moment limit the use of these datasets to few experts, is a lack on efficient visualization systems through the web and interoperable frameworks that allow standardising the access to the city models. The work presented in this paper tries to satisfy these two requirements developing a 3D web-based visualization system based on OGC standards and effective visualization concepts. The architectural framework, based on Services Oriented Architecture (SOA) concepts, provides the 3D city data to a web client designed to support the view process in a very effective way. The first part of the work is to design a framework compliant to the 3D Portrayal Service drafted by the of the Open Geospatial Consortium (OGC) 3D standardization working group. The latter is related to the development of an effective web client able to render in an efficient way the 3D city models.

  2. Accident or homicide--virtual crime scene reconstruction using 3D methods.

    PubMed

    Buck, Ursula; Naether, Silvio; Räss, Beat; Jackowski, Christian; Thali, Michael J

    2013-02-10

    The analysis and reconstruction of forensically relevant events, such as traffic accidents, criminal assaults and homicides are based on external and internal morphological findings of the injured or deceased person. For this approach high-tech methods are gaining increasing importance in forensic investigations. The non-contact optical 3D digitising system GOM ATOS is applied as a suitable tool for whole body surface and wound documentation and analysis in order to identify injury-causing instruments and to reconstruct the course of event. In addition to the surface documentation, cross-sectional imaging methods deliver medical internal findings of the body. These 3D data are fused into a whole body model of the deceased. Additional to the findings of the bodies, the injury inflicting instruments and incident scene is documented in 3D. The 3D data of the incident scene, generated by 3D laser scanning and photogrammetry, is also included into the reconstruction. Two cases illustrate the methods. In the fist case a man was shot in his bedroom and the main question was, if the offender shot the man intentionally or accidentally, as he declared. In the second case a woman was hit by a car, driving backwards into a garage. It was unclear if the driver drove backwards once or twice, which would indicate that he willingly injured and killed the woman. With this work, we demonstrate how 3D documentation, data merging and animation enable to answer reconstructive questions regarding the dynamic development of patterned injuries, and how this leads to a real data based reconstruction of the course of event. PMID:22727689

  3. 3-D electromagnetic modeling of wakefields in accelerator components

    SciTech Connect

    Poole, B.R.; Caporaso, G.J.; Ng, Wang C.; Shang, C.C.; Steich, D.

    1996-09-18

    We discuss the use of 3-D finite-difference time-domain (FDTD) electromagnetic codes for modeling accelerator components. Computational modeling of cylindrically symmetric structures such as induction accelerator cells has been very successful in predicting the wake potential and wake impedances of these structures, but full 3-D modeling of complex structures has been limited due to substantial computer resources required for a full 3-D model. New massively parallel 3-D time domain electromagnetic codes now under development using conforming unstructured meshes allow a substantial increase in the geometric fidelity of the structures being modeled. Development of these new codes are discussed in context of applicability to accelerator problems. Various 3-D structures are tested with an existing cubical cell FDTD code and wake impedances compared with simple analytic models for the structures; results will be used as benchmarks for testing the new time time domain codes. Structures under consideration include a stripline beam position monitor as well as circular and elliptical apertures in circular waveguides. Excellent agreement for monopole and dipole impedances with models were found for these structures below the cutoff frequency of the beam line.

  4. 3-D electromagnetic modeling of wakefields in accelerator components

    SciTech Connect

    Poole, Brian R.; Caporaso, George J.; Ng, Wang C.; Shang, Clifford C.; Steich, David

    1997-02-01

    We discuss the use of 3-D finite-difference time-domain (FDTD) electromagnetic codes for the modeling of accelerator components. Computational modeling of cylindrically symmetric structures such as induction accelerator cells has been extremely successful in predicting the wake potential and wake impedances of these structures, but fully 3-D modeling of complex structures has been limited due to the substantial computer resources required for a fully 3-D model. New massively parallel 3-D time domain electromagnetic codes now under development using conforming unstructured meshes allow a substantial increase in the geometric fidelity of the structures being modeled. Development of these new codes will be discussed in the context of their applicability to accelerator problems. A variety of 3-D structures are tested with an existing cubical cell FDTD code and the wake impedances are compared with simple analytic models for the structures. These results will provide a set of benchmarks for testing the new time domain codes. Structures under consideration include a stripline beam position monitor as well as circular and elliptical apertures in circular waveguides. Excellent agreement for the monopole and dipole impedances with the models are found for these structures below the cutoff frequency of the beam line.

  5. Design and application of a virtual reality 3D engine based on rapid indices

    NASA Astrophysics Data System (ADS)

    Jiang, Nan; Mai, Jin

    2007-06-01

    This article proposes a data structure of a 3D engine based on rapid indices. Taking a model for a construction unit, this data structure can construct a coordinate array with 3D vertex rapidly and arrange those vertices in a sequence of triangle strips or triangle fans, which can be rendered rapidly by OpenGL. This data structure is easy to extend. It can hold texture coordinates, normal coordinates of vertices and a model matrix. Other models can be added to it, deleted from it, or transformed by model matrix, so it is flexible. This data structure also improves the render speed of OpenGL when it holds a large amount of data.

  6. Design and fabrication of concave-convex lens for head mounted virtual reality 3D glasses

    NASA Astrophysics Data System (ADS)

    Deng, Zhaoyang; Cheng, Dewen; Hu, Yuan; Huang, Yifan; Wang, Yongtian

    2015-08-01

    As a kind of light-weighted and convenient tool to achieve stereoscopic vision, virtual reality glasses are gaining more popularity nowadays. For these glasses, molded plastic lenses are often adopted to handle both the imaging property and the cost of massive production. However, the as-built performance of the glass depends on both the optical design and the injection molding process, and maintaining the profile of the lens during injection molding process presents particular challenges. In this paper, optical design is combined with processing simulation analysis to obtain a design result suitable for injection molding. Based on the design and analysis results, different experiments are done using high-quality equipment to optimize the process parameters of injection molding. Finally, a single concave-convex lens is designed with a field-of-view of 90° for the virtual reality 3D glasses. The as-built profile error of the glass lens is controlled within 5μm, which indicates that the designed shape of the lens is fairly realized and the designed optical performance can thus be achieved.

  7. 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.

  8. Models Ion Trajectories in 2D and 3D Electrostatic and Magnetic Fields

    2000-02-21

    SIMION3D7.0REV is a C based ion optics simulation program that can model complex problems using Laplace equation solutions for potential fields. The program uses an ion optics workbench that can hold up to 200 2D and/or 3D electrostatic/magnetic potential arrays. Arrays can have up to 50,000,000 points. SIMION3D7.0''s 32 bit virtual Graphics User Interface provides a highly interactive advanced user environment. All potential arrays are visualized as 3D objects that the user can cut awaymore » to inspect ion trajectories and potential energy surfaces. User programs allow the user to customize the program for specific simulations. A geometry file option supports the definition of highly complex array geometry. Algorithm modifications have improved this version''s computational speed and accuracy.« less

  9. Models Ion Trajectories in 2D and 3D Electrostatic and Magnetic Fields

    SciTech Connect

    Dahl, David

    2000-02-21

    SIMION3D7.0REV is a C based ion optics simulation program that can model complex problems using Laplace equation solutions for potential fields. The program uses an ion optics workbench that can hold up to 200 2D and/or 3D electrostatic/magnetic potential arrays. Arrays can have up to 50,000,000 points. SIMION3D7.0''s 32 bit virtual Graphics User Interface provides a highly interactive advanced user environment. All potential arrays are visualized as 3D objects that the user can cut away to inspect ion trajectories and potential energy surfaces. User programs allow the user to customize the program for specific simulations. A geometry file option supports the definition of highly complex array geometry. Algorithm modifications have improved this version''s computational speed and accuracy.

  10. Multivariate 3D modelling of Scottish soil properties

    NASA Astrophysics Data System (ADS)

    Poggio, Laura; Gimona, Alessandro

    2015-04-01

    Information regarding soil properties across landscapes at national or continental scales is critical for better soil and environmental management and for climate regulation and adaptation policy. The prediction of soil properties variation in space and time and their uncertainty is an important part of environmental modelling. Soil properties, and in particular the 3 fractions of soil texture, exhibit strong co-variation among themselves and therefore taking into account this correlation leads to spatially more accurate results. In this study the continuous vertical and lateral distributions of relevant soil properties in Scottish soils were modelled with a multivariate 3D-GAM+GS approach. The approach used involves 1) modelling the multivariate trend with full 3D spatial correlation, i.e., exploiting the values of the neighbouring pixels in 3D-space, and 2) 3D kriging to interpolate the residuals. The values at each cell for each of the considered depth layers were defined using a hybrid GAM-geostatistical 3D model, combining the fitting of a GAM (generalised Additive Models) to estimate multivariate trend of the variables, using a 3D smoother with related covariates. Gaussian simulations of the model residuals were used as spatial component to account for local details. A dataset of about 26,000 horizons (7,800 profiles) was used for this study. A validation set was randomly selected as 25% of the full dataset. Numerous covariates derived from globally available data, such as MODIS and SRTM, are considered. The results of the 3D-GAM+kriging showed low RMSE values, good R squared and an accurate reproduction of the spatial structure of the data for a range of soil properties. The results have an out-of-sample RMSE between 10 to 15% of the observed range when taking into account the whole profile. The approach followed allows the assessment of the uncertainty of both the trend and the residuals.

  11. Perception-based shape retrieval for 3D building models

    NASA Astrophysics Data System (ADS)

    Zhang, Man; Zhang, Liqiang; Takis Mathiopoulos, P.; Ding, Yusi; Wang, Hao

    2013-01-01

    With the help of 3D search engines, a large number of 3D building models can be retrieved freely online. A serious disadvantage of most rotation-insensitive shape descriptors is their inability to distinguish between two 3D building models which are different at their main axes, but appear similar when one of them is rotated. To resolve this problem, we present a novel upright-based normalization method which not only correctly rotates such building models, but also greatly simplifies and accelerates the abstraction and the matching of building models' shape descriptors. Moreover, the abundance of architectural styles significantly hinders the effective shape retrieval of building models. Our research has shown that buildings with different designs are not well distinguished by the widely recognized shape descriptors for general 3D models. Motivated by this observation and to further improve the shape retrieval quality, a new building matching method is introduced and analyzed based on concepts found in the field of perception theory and the well-known Light Field descriptor. The resulting normalized building models are first classified using the qualitative shape descriptors of Shell and Unevenness which outline integral geometrical and topological information. These models are then put in on orderly fashion with the help of an improved quantitative shape descriptor which we will term as Horizontal Light Field Descriptor, since it assembles detailed shape characteristics. To accurately evaluate the proposed methodology, an enlarged building shape database which extends previous well-known shape benchmarks was implemented as well as a model retrieval system supporting inputs from 2D sketches and 3D models. Various experimental performance evaluation results have shown that, as compared to previous methods, retrievals employing the proposed matching methodology are faster and more consistent with human recognition of spatial objects. In addition these performance

  12. Microfluidic 3D cell culture: from tools to tissue models.

    PubMed

    van Duinen, Vincent; Trietsch, Sebastiaan J; Joore, Jos; Vulto, Paul; Hankemeier, Thomas

    2015-12-01

    The transition from 2D to 3D cell culture techniques is an important step in a trend towards better biomimetic tissue models. Microfluidics allows spatial control over fluids in micrometer-sized channels has become a valuable tool to further increase the physiological relevance of 3D cell culture by enabling spatially controlled co-cultures, perfusion flow and spatial control over of signaling gradients. This paper reviews most important developments in microfluidic 3D culture since 2012. Most efforts were exerted in the field of vasculature, both as a tissue on its own and as part of cancer models. We observe that the focus is shifting from tool building to implementation of specific tissue models. The next big challenge for the field is the full validation of these models and subsequently the implementation of these models in drug development pipelines of the pharmaceutical industry and ultimately in personalized medicine applications. PMID:26094109

  13. Evaluating Biomaterial- and Microfluidic-Based 3D Tumor Models.

    PubMed

    Carvalho, Mariana R; Lima, Daniela; Reis, Rui L; Correlo, Vitor M; Oliveira, Joaquim M

    2015-11-01

    Cancer is a major cause of morbidity and mortality worldwide, with a disease burden estimated to increase over the coming decades. Disease heterogeneity and limited information on cancer biology and disease mechanisms are aspects that 2D cell cultures fail to address. Here, we review the current ‘state-of-the-art’ in 3D tissue-engineering (TE) models developed for, and used in, cancer research. We assess the potential for scaffold-based TE models and microfluidics to fill the gap between 2D models and clinical application. We also discuss recent advances in combining the principles of 3D TE models and microfluidics, with a special focus on biomaterials and the most promising chip-based 3D models. PMID:26603572

  14. A spherical harmonics intensity model for 3D segmentation and 3D shape analysis of heterochromatin foci.

    PubMed

    Eck, Simon; Wörz, Stefan; Müller-Ott, Katharina; Hahn, Matthias; Biesdorf, Andreas; Schotta, Gunnar; Rippe, Karsten; Rohr, Karl

    2016-08-01

    The genome is partitioned into regions of euchromatin and heterochromatin. The organization of heterochromatin is important for the regulation of cellular processes such as chromosome segregation and gene silencing, and their misregulation is linked to cancer and other diseases. We present a model-based approach for automatic 3D segmentation and 3D shape analysis of heterochromatin foci from 3D confocal light microscopy images. Our approach employs a novel 3D intensity model based on spherical harmonics, which analytically describes the shape and intensities of the foci. The model parameters are determined by fitting the model to the image intensities using least-squares minimization. To characterize the 3D shape of the foci, we exploit the computed spherical harmonics coefficients and determine a shape descriptor. We applied our approach to 3D synthetic image data as well as real 3D static and real 3D time-lapse microscopy images, and compared the performance with that of previous approaches. It turned out that our approach yields accurate 3D segmentation results and performs better than previous approaches. We also show that our approach can be used for quantifying 3D shape differences of heterochromatin foci. PMID:27037463

  15. The Use of 3D Virtual Learning Environments in Training Foreign Language Pre-Service Teachers

    ERIC Educational Resources Information Center

    Can, Tuncer; Simsek, Irfan

    2015-01-01

    The recent developments in computer and Internet technologies and in three dimensional modelling necessitates the new approaches and methods in the education field and brings new opportunities to the higher education. The Internet and virtual learning environments have changed the learning opportunities by diversifying the learning options not…

  16. Improving 3d Spatial Queries Search: Newfangled Technique of Space Filling Curves in 3d City Modeling

    NASA Astrophysics Data System (ADS)

    Uznir, U.; Anton, F.; Suhaibah, A.; Rahman, A. A.; Mioc, D.

    2013-09-01

    The advantages of three dimensional (3D) city models can be seen in various applications including photogrammetry, urban and regional planning, computer games, etc.. They expand the visualization and analysis capabilities of Geographic Information Systems on cities, and they can be developed using web standards. However, these 3D city models consume much more storage compared to two dimensional (2D) spatial data. They involve extra geometrical and topological information together with semantic data. Without a proper spatial data clustering method and its corresponding spatial data access method, retrieving portions of and especially searching these 3D city models, will not be done optimally. Even though current developments are based on an open data model allotted by the Open Geospatial Consortium (OGC) called CityGML, its XML-based structure makes it challenging to cluster the 3D urban objects. In this research, we propose an opponent data constellation technique of space-filling curves (3D Hilbert curves) for 3D city model data representation. Unlike previous methods, that try to project 3D or n-dimensional data down to 2D or 3D using Principal Component Analysis (PCA) or Hilbert mappings, in this research, we extend the Hilbert space-filling curve to one higher dimension for 3D city model data implementations. The query performance was tested using a CityGML dataset of 1,000 building blocks and the results are presented in this paper. The advantages of implementing space-filling curves in 3D city modeling will improve data retrieval time by means of optimized 3D adjacency, nearest neighbor information and 3D indexing. The Hilbert mapping, which maps a subinterval of the [0, 1] interval to the corresponding portion of the d-dimensional Hilbert's curve, preserves the Lebesgue measure and is Lipschitz continuous. Depending on the applications, several alternatives are possible in order to cluster spatial data together in the third dimension compared to its

  17. STELLOPT Modeling of the 3D Diagnostic Response in ITER

    SciTech Connect

    Lazerson, Samuel A

    2013-05-07

    The ITER three dimensional diagnostic response to an n=3 resonant magnetic perturbation is modeled using the STELLOPT code. The in-vessel coils apply a resonant magnetic perturbation (RMP) fi eld which generates a 4 cm edge displacement from axisymmetry as modeled by the VMEC 3D equilibrium code. Forward modeling of flux loop and magnetic probe response with the DIAGNO code indicates up to 20 % changes in measured plasma signals. Simulated LIDAR measurements of electron temperature indicate 2 cm shifts on the low field side of the plasma. This suggests that the ITER diagnostic will be able to diagnose the 3D structure of the equilibria.

  18. MR image denoising method for brain surface 3D modeling

    NASA Astrophysics Data System (ADS)

    Zhao, De-xin; Liu, Peng-jie; Zhang, De-gan

    2014-11-01

    Three-dimensional (3D) modeling of medical images is a critical part of surgical simulation. In this paper, we focus on the magnetic resonance (MR) images denoising for brain modeling reconstruction, and exploit a practical solution. We attempt to remove the noise existing in the MR imaging signal and preserve the image characteristics. A wavelet-based adaptive curve shrinkage function is presented in spherical coordinates system. The comparative experiments show that the denoising method can preserve better image details and enhance the coefficients of contours. Using these denoised images, the brain 3D visualization is given through surface triangle mesh model, which demonstrates the effectiveness of the proposed method.

  19. Automatic Texture Reconstruction of 3d City Model from Oblique Images

    NASA Astrophysics Data System (ADS)

    Kang, Junhua; Deng, Fei; Li, Xinwei; Wan, Fang

    2016-06-01

    In recent years, the photorealistic 3D city models are increasingly important in various geospatial applications related to virtual city tourism, 3D GIS, urban planning, real-estate management. Besides the acquisition of high-precision 3D geometric data, texture reconstruction is also a crucial step for generating high-quality and visually realistic 3D models. However, most of the texture reconstruction approaches are probably leading to texture fragmentation and memory inefficiency. In this paper, we introduce an automatic framework of texture reconstruction to generate textures from oblique images for photorealistic visualization. Our approach include three major steps as follows: mesh parameterization, texture atlas generation and texture blending. Firstly, mesh parameterization procedure referring to mesh segmentation and mesh unfolding is performed to reduce geometric distortion in the process of mapping 2D texture to 3D model. Secondly, in the texture atlas generation step, the texture of each segmented region in texture domain is reconstructed from all visible images with exterior orientation and interior orientation parameters. Thirdly, to avoid color discontinuities at boundaries between texture regions, the final texture map is generated by blending texture maps from several corresponding images. We evaluated our texture reconstruction framework on a dataset of a city. The resulting mesh model can get textured by created texture without resampling. Experiment results show that our method can effectively mitigate the occurrence of texture fragmentation. It is demonstrated that the proposed framework is effective and useful for automatic texture reconstruction of 3D city model.

  20. Potential of 3D City Models to assess flood vulnerability

    NASA Astrophysics Data System (ADS)

    Schröter, Kai; Bochow, Mathias; Schüttig, Martin; Nagel, Claus; Ross, Lutz; Kreibich, Heidi

    2016-04-01

    Vulnerability, as the product of exposure and susceptibility, is a key factor of the flood risk equation. Furthermore, the estimation of flood loss is very sensitive to the choice of the vulnerability model. Still, in contrast to elaborate hazard simulations, vulnerability is often considered in a simplified manner concerning the spatial resolution and geo-location of exposed objects as well as the susceptibility of these objects at risk. Usually, area specific potential flood loss is quantified on the level of aggregated land-use classes, and both hazard intensity and resistance characteristics of affected objects are represented in highly simplified terms. We investigate the potential of 3D City Models and spatial features derived from remote sensing data to improve the differentiation of vulnerability in flood risk assessment. 3D City Models are based on CityGML, an application scheme of the Geography Markup Language (GML), which represents the 3D geometry, 3D topology, semantics and appearance of objects on different levels of detail. As such, 3D City Models offer detailed spatial information which is useful to describe the exposure and to characterize the susceptibility of residential buildings at risk. This information is further consolidated with spatial features of the building stock derived from remote sensing data. Using this database a spatially detailed flood vulnerability model is developed by means of data-mining. Empirical flood damage data are used to derive and to validate flood susceptibility models for individual objects. We present first results from a prototype application in the city of Dresden, Germany. The vulnerability modeling based on 3D City Models and remote sensing data is compared i) to the generally accepted good engineering practice based on area specific loss potential and ii) to a highly detailed representation of flood vulnerability based on a building typology using urban structure types. Comparisons are drawn in terms of

  1. 3D MHD Models of Active Region Loops

    NASA Technical Reports Server (NTRS)

    Ofman, Leon

    2004-01-01

    Present imaging and spectroscopic observations of active region loops allow to determine many physical parameters of the coronal loops, such as the density, temperature, velocity of flows in loops, and the magnetic field. However, due to projection effects many of these parameters remain ambiguous. Three dimensional imaging in EUV by the STEREO spacecraft will help to resolve the projection ambiguities, and the observations could be used to setup 3D MHD models of active region loops to study the dynamics and stability of active regions. Here the results of 3D MHD models of active region loops are presented, and the progress towards more realistic 3D MHD models of active regions. In particular the effects of impulsive events on the excitation of active region loop oscillations, and the generation, propagations and reflection of EIT waves are shown. It is shown how 3D MHD models together with 3D EUV observations can be used as a diagnostic tool for active region loop physical parameters, and to advance the science of the sources of solar coronal activity.

  2. 3D head model classification using optimized EGI

    NASA Astrophysics Data System (ADS)

    Tong, Xin; Wong, Hau-san; Ma, Bo

    2006-02-01

    With the general availability of 3D digitizers and scanners, 3D graphical models have been used widely in a variety of applications. This has led to the development of search engines for 3D models. Especially, 3D head model classification and retrieval have received more and more attention in view of their many potential applications in criminal identifications, computer animation, movie industry and medical industry. This paper addresses the 3D head model classification problem using 2D subspace analysis methods such as 2D principal component analysis (2D PCA[3]) and 2D fisher discriminant analysis (2DLDA[5]). It takes advantage of the fact that the histogram is a 2D image, and we can extract the most useful information from these 2D images to get a good result accordingingly. As a result, there are two main advantages: First, we can perform less calculation to obtain the same rate of classification; second, we can reduce the dimensionality more than PCA to obtain a higher efficiency.

  3. Vhrs Stereo Images for 3d Modelling of Buildings

    NASA Astrophysics Data System (ADS)

    Bujakiewicz, A.; Holc, M.

    2012-07-01

    The paper presents the project which was carried out in the Photogrammetric Laboratory of Warsaw University of Technology. The experiment is concerned with the extraction of 3D vector data for buildings creation from 3D photogrammetric model based on the Ikonos stereo images. The model was reconstructed with photogrammetric workstation - Summit Evolution combined with ArcGIS 3D platform. Accuracy of 3D model was significantly improved by use for orientation of pair of satellite images the stereo measured tie points distributed uniformly around the model area in addition to 5 control points. The RMS for model reconstructed on base of the RPC coefficients only were 16,6 m, 2,7 m and 47,4 m, for X, Y and Z coordinates, respectively. By addition of 5 control points the RMS were improved to 0,7 m, 0,7 m 1,0 m, where the best results were achieved when RMS were estimated from deviations in 17 check points (with 5 control points)and amounted to 0,4 m, 0,5 m and 0,6 m, for X, Y, and Z respectively. The extracted 3D vector data for buildings were integrated with 2D data of the ground footprints and afterwards they were used for 3D modelling of buildings in Google SketchUp software. The final results were compared with the reference data obtained from other sources. It was found that the shape of buildings (in concern to the number of details) had been reconstructed on level of LoD1, when the accuracy of these models corresponded to the level of LoD2.

  4. 3D model of amphioxus steroid receptor complexed with estradiol

    SciTech Connect

    Baker, Michael E.; Chang, David J.

    2009-08-28

    The origins of signaling by vertebrate steroids are not fully understood. An important advance was the report that an estrogen-binding steroid receptor [SR] is present in amphioxus, a basal chordate with a similar body plan as vertebrates. To investigate the evolution of estrogen-binding to steroid receptors, we constructed a 3D model of amphioxus SR complexed with estradiol. This 3D model indicates that although the SR is activated by estradiol, some interactions between estradiol and human ER{alpha} are not conserved in the SR, which can explain the low affinity of estradiol for the SR. These differences between the SR and ER{alpha} in the steroid-binding domain are sufficient to suggest that another steroid is the physiological regulator of the SR. The 3D model predicts that mutation of Glu-346 to Gln will increase the affinity of testosterone for amphioxus SR and elucidate the evolution of steroid-binding to nuclear receptors.

  5. Quality of 3D Models Generated by SFM Technology

    NASA Astrophysics Data System (ADS)

    Marčiš, Marián

    2013-12-01

    Using various types of automation in digital photogrammetry is associated with questions such as the accuracy of a 3D model generated on various types of surfaces and textures, the financial costs of the equipment needed, and also the time costs of the processing. This topic deals with the actual technology of computer vision, which allows the automated exterior orientation of images, camera calibration, and the generation of 3D models directly from images of the object itself, based on the automatic detection of significant points. Detailed testing is done using the Agisoft PhotoScan system, and the camera configuration is solved with respect to the accuracy of the 3D model generated and the time consumption of the calculations for the different types of textures and the different settings for the processing.

  6. Recovering a collapsed medieval fresco by using 3D modeling techniques

    NASA Astrophysics Data System (ADS)

    Chiabrando, F.; Rinaudo, F.

    2014-05-01

    The paper presents the results of a reconstruction of the 3D model of a dome and of a medieval fresco, collapsed after an earthquake and now reconstructed in significant portions, to offer to the visitors a possible reconstruction of the lost masterpiece of medieval art. After the earthquake the collapsed dome was replaced by means of a concrete sphere connected with the survived portions of the old dome's timber. The old dome shape and the fresco were virtually reconstructed thanks to a set of historical pictures obtained by Italian, USA and German archives; those images have been calibrated and oriented by using modern digital photogrammetric approach and a realistic 3D model of the old inner surface of the dome has been realised. By using a LiDAR survey the 3D model of the apse and of the dome, has been set up and the boundaries between original and new structures have been reconstructed by visual evidences.The new dome has been virtually erased and the old dome with the fresco 3D model inserted allowing the reconstruction of the apse as it was before the earthquake. This virtual 3D model has been used to realise a 1:1 scale model of the old dome where the restorers fit some parts of the old fresco fragments recovered just after the earthquake, cleaned and classified. The fresco images correctly oriented inside the reconstructed dome have been projected on plane surfaces by using azimuthal orthographic projections of small portions of the dome in order to reduce the geometric deformations and to allow the mosaicking of these small planes onto a spherical surface.

  7. 3D surface digitizing and modeling development at ITRI

    NASA Astrophysics Data System (ADS)

    Hsueh, Wen-Jean

    2000-06-01

    This paper gives an overview of the research and development activities in 3D surface digitizing and modeling conducted at the Industrial Technology Research Institute (ITRI) of Taiwan in the past decade. As a major technology and consulting service provider of the area, ITRI has developed 3D laser scanning digitizers ranging from low-cost compacts, industrial CAD/CAM digitizing, to large human body scanner, with in-house 3D surface modeling software to provide total solution in reverse engineering that requires processing capabilities of large number of 3D data. Based on both hardware and software technologies in scanning, merging, registration, surface fitting, reconstruction, and compression, ITRI is now exploring innovative methodologies that provide higher performances, including hardware-based correlation algorithms with advanced camera designs, animation surface model reconstruction, and optical tracking for motion capture. It is expected that the need for easy and fast high-quality 3D information in the near future will grow exponentially, at the same amazing rate as the internet and the human desire for realistic and natural images.

  8. Diffusion approximation for modeling of 3-D radiation distributions

    SciTech Connect

    Zardecki, A.; Gerstl, S.A.W.; De Kinder, R.E. Jr.

    1985-01-01

    A three-dimensional transport code DIF3D, based on the diffusion approximation, is used to model the spatial distribution of radiation energy arising from volumetric isotropic sources. Future work will be concerned with the determination of irradiances and modeling of realistic scenarios, relevant to the battlefield conditions. 8 refs., 4 figs.

  9. Lift-Off: Using Reference Imagery and Freehand Sketching to Create 3D Models in VR.

    PubMed

    Jackson, Bret; Keefe, Daniel F

    2016-04-01

    Three-dimensional modeling has long been regarded as an ideal application for virtual reality (VR), but current VR-based 3D modeling tools suffer from two problems that limit creativity and applicability: (1) the lack of control for freehand modeling, and (2) the difficulty of starting from scratch. To address these challenges, we present Lift-Off, an immersive 3D interface for creating complex models with a controlled, handcrafted style. Artists start outside of VR with 2D sketches, which are then imported and positioned in VR. Then, using a VR interface built on top of image processing algorithms, 2D curves within the sketches are selected interactively and "lifted" into space to create a 3D scaffolding for the model. Finally, artists sweep surfaces along these curves to create 3D models. Evaluations are presented for both long-term users and for novices who each created a 3D sailboat model from the same starting sketch. Qualitative results are positive, with the visual style of the resulting models of animals and other organic subjects as well as architectural models matching what is possible with traditional fine art media. In addition, quantitative data from logging features built into the software are used to characterize typical tool use and suggest areas for further refinement of the interface. PMID:26780801

  10. Construction of a 3-D anatomical model for teaching temporal lobectomy.

    PubMed

    de Ribaupierre, Sandrine; Wilson, Timothy D

    2012-06-01

    Although we live and work in 3 dimensional space, most of the anatomical teaching during medical school is done on 2-D (books, TV and computer screens, etc). 3-D spatial abilities are essential for a surgeon but teaching spatial skills in a non-threatening and safe educational environment is a much more difficult pedagogical task. Currently, initial anatomical knowledge formation or specific surgical anatomy techniques, are taught either in the OR itself, or in cadaveric labs; which means that the trainee has only limited exposure. 3-D computer models incorporated into virtual learning environments may provide an intermediate and key step in a blended learning approach for spatially challenging anatomical knowledge formation. Specific anatomical structures and their spatial orientation can be further clinically contextualized through demonstrations of surgical procedures in the 3-D digital environments. Recordings of digital models enable learner reviews, taking as much time as they want, stopping the demonstration, and/or exploring the model to understand the anatomical relation of each structure. We present here how a temporal lobectomy virtual model has been developed to aid residents and fellows conceptualization of the anatomical relationships between different cerebral structures during that procedure. We suggest in comparison to cadaveric dissection, such virtual models represent a cost effective pedagogical methodology providing excellent support for anatomical learning and surgical technique training. PMID:22513297

  11. Modelling Gaia CCD pixels with Silvaco 3D engineering software

    NASA Astrophysics Data System (ADS)

    Seabroke, G. M.; Prod'Homme, T.; Hopkinson, G.; Burt, D.; Robbins, M.; Holland, A.

    2011-02-01

    Gaia will only achieve its unprecedented measurement accuracy requirements with detailed calibration and correction for radiation damage. We present our Silvaco 3D engineering software model of the Gaia CCD pixel and two of its applications for Gaia: (1) physically interpreting supplementary buried channel (SBC) capacity measurements (pocket-pumping and first pixel response) in terms of e2v manufacturing doping alignment tolerances; and (2) deriving electron densities within a charge packet as a function of the number of constituent electrons and 3D position within the charge packet as input to microscopic models being developed to simulate radiation damage.

  12. Geospatial Modelling Approach for 3d Urban Densification Developments

    NASA Astrophysics Data System (ADS)

    Koziatek, O.; Dragićević, S.; Li, S.

    2016-06-01

    With growing populations, economic pressures, and the need for sustainable practices, many urban regions are rapidly densifying developments in the vertical built dimension with mid- and high-rise buildings. The location of these buildings can be projected based on key factors that are attractive to urban planners, developers, and potential buyers. Current research in this area includes various modelling approaches, such as cellular automata and agent-based modelling, but the results are mostly linked to raster grids as the smallest spatial units that operate in two spatial dimensions. Therefore, the objective of this research is to develop a geospatial model that operates on irregular spatial tessellations to model mid- and high-rise buildings in three spatial dimensions (3D). The proposed model is based on the integration of GIS, fuzzy multi-criteria evaluation (MCE), and 3D GIS-based procedural modelling. Part of the City of Surrey, within the Metro Vancouver Region, Canada, has been used to present the simulations of the generated 3D building objects. The proposed 3D modelling approach was developed using ESRI's CityEngine software and the Computer Generated Architecture (CGA) language.

  13. Robust model-based 3d/3D fusion using sparse matching for minimally invasive surgery.

    PubMed

    Neumann, Dominik; Grbic, Sasa; John, Matthias; Navab, Nassir; Hornegger, Joachim; Ionasec, Razvan

    2013-01-01

    Classical surgery is being disrupted by minimally invasive and transcatheter procedures. As there is no direct view or access to the affected anatomy, advanced imaging techniques such as 3D C-arm CT and C-arm fluoroscopy are routinely used for intra-operative guidance. However, intra-operative modalities have limited image quality of the soft tissue and a reliable assessment of the cardiac anatomy can only be made by injecting contrast agent, which is harmful to the patient and requires complex acquisition protocols. We propose a novel sparse matching approach for fusing high quality pre-operative CT and non-contrasted, non-gated intra-operative C-arm CT by utilizing robust machine learning and numerical optimization techniques. Thus, high-quality patient-specific models can be extracted from the pre-operative CT and mapped to the intra-operative imaging environment to guide minimally invasive procedures. Extensive quantitative experiments demonstrate that our model-based fusion approach has an average execution time of 2.9 s, while the accuracy lies within expert user confidence intervals. PMID:24505663

  14. 3D Model Generation From the Engineering Drawing

    NASA Astrophysics Data System (ADS)

    Vaský, Jozef; Eliáš, Michal; Bezák, Pavol; Červeňanská, Zuzana; Izakovič, Ladislav

    2010-01-01

    The contribution deals with the transformation of engineering drawings in a paper form into a 3D computer representation. A 3D computer model can be further processed in CAD/CAM system, it can be modified, archived, and a technical drawing can be then generated from it as well. The transformation process from paper form to the data one is a complex and difficult one, particularly owing to the different types of drawings, forms of displayed objects and encountered errors and deviations from technical standards. The algorithm for 3D model generating from an orthogonal vector input representing a simplified technical drawing of the rotational part is described in this contribution. The algorithm was experimentally implemented as ObjectARX application in the AutoCAD system and the test sample as the representation of the rotational part was used for verificaton.

  15. Integration of 3D photogrammetric outcrop models in the reservoir modelling workflow

    NASA Astrophysics Data System (ADS)

    Deschamps, Remy; Joseph, Philippe; Lerat, Olivier; Schmitz, Julien; Doligez, Brigitte; Jardin, Anne

    2014-05-01

    3D outcrop data, including geostatistical modelling and fluid flow simulations The case study is a turbidite reservoir analog in Northern Spain (Ainsa). In this case study, we can compare reservoir models that have been built with conventional data set (1D pseudowells), and reservoir model built from 3D outcrop data directly used to constrain the reservoir architecture. This approach allows us to assess the benefits of integrating geotagged 3D outcrop data into reservoir models. References: HODGETTS, D., (2013): Laser scanning and digital outcrop geology in the petroleum industry : a review. Marine and Petroleum Geology, 46, 335-354. McCAFFREY, K.J.W., JONES, R.R., HOLDSWORTH, R.E., WILSON, R.W., CLEGG, P., IMBER, J., HOLLIMAN, N., TRINKS, I., (2005): Unlocking the spatial dimension: digital technologies and the future of geoscience fieldwork. Journal of the Geological Society 162, 927-938 PRINGLE, J.K., HOWELL, J.A., HODGETTS, D., WESTERMAN, A.R., HODGSON, D.M., 2006. Virtual outcrop models of petroleum reservoir analogues: a review of the current state-of-the-art. First Break 24, 33-42.

  16. 3D shape decomposition and comparison for gallbladder modeling

    NASA Astrophysics Data System (ADS)

    Huang, Weimin; Zhou, Jiayin; Liu, Jiang; Zhang, Jing; Yang, Tao; Su, Yi; Law, Gim Han; Chui, Chee Kong; Chang, Stephen

    2011-03-01

    This paper presents an approach to gallbladder shape comparison by using 3D shape modeling and decomposition. The gallbladder models can be used for shape anomaly analysis and model comparison and selection in image guided robotic surgical training, especially for laparoscopic cholecystectomy simulation. The 3D shape of a gallbladder is first represented as a surface model, reconstructed from the contours segmented in CT data by a scheme of propagation based voxel learning and classification. To better extract the shape feature, the surface mesh is further down-sampled by a decimation filter and smoothed by a Taubin algorithm, followed by applying an advancing front algorithm to further enhance the regularity of the mesh. Multi-scale curvatures are then computed on the regularized mesh for the robust saliency landmark localization on the surface. The shape decomposition is proposed based on the saliency landmarks and the concavity, measured by the distance from the surface point to the convex hull. With a given tolerance the 3D shape can be decomposed and represented as 3D ellipsoids, which reveal the shape topology and anomaly of a gallbladder. The features based on the decomposed shape model are proposed for gallbladder shape comparison, which can be used for new model selection. We have collected 19 sets of abdominal CT scan data with gallbladders, some shown in normal shape and some in abnormal shapes. The experiments have shown that the decomposed shapes reveal important topology features.

  17. Geodiversity: Exploration of 3D geological model space

    NASA Astrophysics Data System (ADS)

    Lindsay, M. D.; Jessell, M. W.; Ailleres, L.; Perrouty, S.; de Kemp, E.; Betts, P. G.

    2013-05-01

    The process of building a 3D model necessitates the reconciliation of field observations, geophysical interpretation, geological data uncertainty and the prevailing tectonic evolution hypotheses and interpretations. Uncertainty is compounded when clustered data points collected at local scales are statistically upscaled to one or two points for use in regional models. Interpretation is required to interpolate between sparse field data points using ambiguous geophysical data in covered terranes. It becomes clear that multiple interpretations are possible during model construction. The various interpretations are considered as potential natural representatives, but pragmatism typically dictates that just a single interpretation is offered by the modelling process. Uncertainties are introduced into the 3D model during construction from a variety of sources and through data set optimisation that produces a single model. Practices such as these are likely to result in a model that does not adequately represent the target geology. A set of geometrical ‘geodiversity’ metrics are used to analyse a 3D model of the Gippsland Basin, southeastern Australia after perturbing geological input data via uncertainty simulation. The resulting sets of perturbed geological observations are used to calculate a suite of geological 3D models that display a range of geological architectures. The concept of biodiversity has been adapted for the geosciences to quantify geometric variability, or geodiversity, between models in order to understand the effect uncertainty has models geometry. Various geometrical relationships (depth, volume, contact surface area, curvature and geological complexity) are used to describe the range of possibilities exhibited throughout the model suite. End-member models geodiversity metrics are classified in a similar manner to taxonomic descriptions. Further analysis of the model suite is performed using principal component analysis (PCA) to determine

  18. NanTroSEIZE in 3-D: Creating a Virtual Research Experience in Undergraduate Geoscience Courses

    NASA Astrophysics Data System (ADS)

    Reed, D. L.; Bangs, N. L.; Moore, G. F.; Tobin, H.

    2009-12-01

    Marine research programs, both large and small, have increasingly added a web-based component to facilitate outreach to K-12 and the public, in general. These efforts have included, among other activities, information-rich websites, ship-to-shore communication with scientists during expeditions, blogs at sea, clips on YouTube, and information about daily shipboard activities. Our objective was to leverage a portion of the vast collection of data acquired through the NSF-MARGINS program to create a learning tool with a long lifespan for use in undergraduate geoscience courses. We have developed a web-based virtual expedition, NanTroSEIZE in 3-D, based on a seismic survey associated with the NanTroSEIZE program of NSF-MARGINS and IODP to study the properties of the plate boundary fault system in the upper limit of the seismogenic zone off Japan. The virtual voyage can be used in undergraduate classes at anytime, since it is not directly tied to the finite duration of a specific seagoing project. The website combines text, graphics, audio and video to place learning in an experiential framework as students participate on the expedition and carry out research. Students learn about the scientific background of the program, especially the critical role of international collaboration, and meet the chief scientists before joining the sea-going expedition. Students are presented with the principles of 3-D seismic imaging, data processing and interpretation while mapping and identifying the active faults that were the likely sources of devastating earthquakes and tsunamis in Japan in 1944 and 1948. They also learn about IODP drilling that began in 2007 and will extend through much of the next decade. The website is being tested in undergraduate classes in fall 2009 and will be distributed through the NSF-MARGINS website (http://www.nsf-margins.org/) and the MARGINS Mini-lesson section of the Science Education Resource Center (SERC) (http

  19. Development of a High Resolution 3D Infant Stomach Model for Surgical Planning

    NASA Astrophysics Data System (ADS)

    Chaudry, Qaiser; Raza, S. Hussain; Lee, Jeonggyu; Xu, Yan; Wulkan, Mark; Wang, May D.

    Medical surgical procedures have not changed much during the past century due to the lack of accurate low-cost workbench for testing any new improvement. The increasingly cheaper and powerful computer technologies have made computer-based surgery planning and training feasible. In our work, we have developed an accurate 3D stomach model, which aims to improve the surgical procedure that treats the infant pediatric and neonatal gastro-esophageal reflux disease (GERD). We generate the 3-D infant stomach model based on in vivo computer tomography (CT) scans of an infant. CT is a widely used clinical imaging modality that is cheap, but with low spatial resolution. To improve the model accuracy, we use the high resolution Visible Human Project (VHP) in model building. Next, we add soft muscle material properties to make the 3D model deformable. Then we use virtual reality techniques such as haptic devices to make the 3D stomach model deform upon touching force. This accurate 3D stomach model provides a workbench for testing new GERD treatment surgical procedures. It has the potential to reduce or eliminate the extensive cost associated with animal testing when improving any surgical procedure, and ultimately, to reduce the risk associated with infant GERD surgery.

  20. 3D Geological Model for "LUSI" - a Deep Geothermal System

    NASA Astrophysics Data System (ADS)

    Sohrabi, Reza; Jansen, Gunnar; Mazzini, Adriano; Galvan, Boris; Miller, Stephen A.

    2016-04-01

    Geothermal applications require the correct simulation of flow and heat transport processes in porous media, and many of these media, like deep volcanic hydrothermal systems, host a certain degree of fracturing. This work aims to understand the heat and fluid transport within a new-born sedimentary hosted geothermal system, termed Lusi, that began erupting in 2006 in East Java, Indonesia. Our goal is to develop conceptual and numerical models capable of simulating multiphase flow within large-scale fractured reservoirs such as the Lusi region, with fractures of arbitrary size, orientation and shape. Additionally, these models can also address a number of other applications, including Enhanced Geothermal Systems (EGS), CO2 sequestration (Carbon Capture and Storage CCS), and nuclear waste isolation. Fractured systems are ubiquitous, with a wide-range of lengths and scales, making difficult the development of a general model that can easily handle this complexity. We are developing a flexible continuum approach with an efficient, accurate numerical simulator based on an appropriate 3D geological model representing the structure of the deep geothermal reservoir. Using previous studies, borehole information and seismic data obtained in the framework of the Lusi Lab project (ERC grant n°308126), we present here the first 3D geological model of Lusi. This model is calculated using implicit 3D potential field or multi-potential fields, depending on the geological context and complexity. This method is based on geological pile containing the geological history of the area and relationship between geological bodies allowing automatic computation of intersections and volume reconstruction. Based on the 3D geological model, we developed a new mesh algorithm to create hexahedral octree meshes to transfer the structural geological information for 3D numerical simulations to quantify Thermal-Hydraulic-Mechanical-Chemical (THMC) physical processes.

  1. Performance and Cognitive Assessment in 3-D Modeling

    ERIC Educational Resources Information Center

    Fahrer, Nolan E.; Ernst, Jeremy V.; Branoff, Theodore J.; Clark, Aaron C.

    2011-01-01

    The purpose of this study was to investigate identifiable differences between performance and cognitive assessment scores in a 3-D modeling unit of an engineering drafting course curriculum. The study aimed to provide further investigation of the need of skill-based assessments in engineering/technical graphics courses to potentially increase…

  2. A Sketching Interface for Freeform 3D Modeling

    NASA Astrophysics Data System (ADS)

    Igarashi, Takeo

    This chapter introduces Teddy, a sketch-based modeling system to quickly and easily design freeform models such as stuffed animals and other rotund objects. The user draws several 2D freeform strokes interactively on the screen and the system automatically constructs plausible 3D polygonal surfaces. Our system supports several modeling operations, including the operation to construct a 3D polygonal surface from a 2D silhouette drawn by the user: it inflates the region surrounded by the silhouette making a wide area fat, and a narrow area thin. Teddy, our prototype system, is implemented as a Java program, and the mesh construction is done in real-time on a standard PC. Our informal user study showed that a first-time user masters the operations within 10 minutes, and can construct interesting 3D models within minutes. We also report the result of a case study where a high school teacher taught various 3D concepts in geography using the system.

  3. Assessment of 3D Models Used in Contours Studies

    ERIC Educational Resources Information Center

    Alvarez, F. J. Ayala; Parra, E. B. Blazquez; Tubio, F. Montes

    2015-01-01

    This paper presents an experimental research focusing on the view of first year students. The aim is to check the quality of implementing 3D models integrated in the curriculum. We search to determine students' preference between the various means facilitated in order to understand the given subject. Students have been respondents to prove the…

  4. 3DVEM Software Modules for Efficient Management of Point Clouds and Photorealistic 3d Models

    NASA Astrophysics Data System (ADS)

    Fabado, S.; Seguí, A. E.; Cabrelles, M.; Navarro, S.; García-De-San-Miguel, D.; Lerma, J. L.

    2013-07-01

    Cultural heritage managers in general and information users in particular are not usually used to deal with high-technological hardware and software. On the contrary, information providers of metric surveys are most of the times applying latest developments for real-life conservation and restoration projects. This paper addresses the software issue of handling and managing either 3D point clouds or (photorealistic) 3D models to bridge the gap between information users and information providers as regards the management of information which users and providers share as a tool for decision-making, analysis, visualization and management. There are not many viewers specifically designed to handle, manage and create easily animations of architectural and/or archaeological 3D objects, monuments and sites, among others. 3DVEM - 3D Viewer, Editor & Meter software will be introduced to the scientific community, as well as 3DVEM - Live and 3DVEM - Register. The advantages of managing projects with both sets of data, 3D point cloud and photorealistic 3D models, will be introduced. Different visualizations of true documentation projects in the fields of architecture, archaeology and industry will be presented. Emphasis will be driven to highlight the features of new userfriendly software to manage virtual projects. Furthermore, the easiness of creating controlled interactive animations (both walkthrough and fly-through) by the user either on-the-fly or as a traditional movie file will be demonstrated through 3DVEM - Live.

  5. 3d model for site effect assessment at Nice (France)

    NASA Astrophysics Data System (ADS)

    Bertrand, E.; Courrioux, G.; Bourgine, B.; Bour, M.; Guillen, A.; Mouroux, P.; Devaux, E.; Duval, A. M.

    2003-04-01

    Assessment of lithologic site effects is based on an accurate knowledge of properties and geometry of superficial geological formations, i.e. ideally a 3D-4G subsurface model (Geology, Geomorphology, Geophysics, Geotechnics). Such a model has been achieved using a 3D geomodeler ("Geological Editor" developed at BRGM) that allows building 3D volumes of geological formations starting from drill-holes data, sections, and geological maps. This software uses a pseudo-stratigraphic pile in order to reproduce geological history and structural relationships (erosion, deposit). The interpolation is achieved through a 3D potential field. A geostatistical formulation allows to consider data points of a geological limit as equipotential, and sructural dips as gradient inputs for the 3D field interpolation. Then isosurfaces corresponding to each limit are combined using formation relationships to provide volumic models of geological formations. The first task was to identify the relevant geological formations underlying in Nice area. In a first approach Mesozoic bedrock, Pliocene bedrock, and Quaternary alluvial deposits have been distinguished considering their seismic properties. Then alluvions have been subdivided into 9 groups according to their lithology and granulometry. Modelling has been performed considering 2 major erosion surfaces, post-Mesozoic and post-Pliocene. The succession of Quaternary alluviums have been considered as "onlap deposits". Given adjacent lithologies contained in maps and drill holes, these relations lead to logical identification of the roof of formations to be interpolated. The distribution of modeled geological formations can be visualised in 3 dimensions or in 2D sections. Besides the visual interest of 3D representations, the model is first used to build a series of earth columns over a 50m/50m 2D grid. A statistical analysis allowed to identify 73 existing configurations in the Nice district area. Among these, only 15 configurations

  6. CamMedNP: Building the Cameroonian 3D structural natural products database for virtual screening

    PubMed Central

    2013-01-01

    Background Computer-aided drug design (CADD) often involves virtual screening (VS) of large compound datasets and the availability of such is vital for drug discovery protocols. We present CamMedNP - a new database beginning with more than 2,500 compounds of natural origin, along with some of their derivatives which were obtained through hemisynthesis. These are pure compounds which have been previously isolated and characterized using modern spectroscopic methods and published by several research teams spread across Cameroon. Description In the present study, 224 distinct medicinal plant species belonging to 55 plant families from the Cameroonian flora have been considered. About 80 % of these have been previously published and/or referenced in internationally recognized journals. For each compound, the optimized 3D structure, drug-like properties, plant source, collection site and currently known biological activities are given, as well as literature references. We have evaluated the “drug-likeness” of this database using Lipinski’s “Rule of Five”. A diversity analysis has been carried out in comparison with the ChemBridge diverse database. Conclusion CamMedNP could be highly useful for database screening and natural product lead generation programs. PMID:23590173

  7. Toward virtual anatomy: a stereoscopic 3-D interactive multimedia computer program for cranial osteology.

    PubMed

    Trelease, R B

    1996-01-01

    Advances in computer visualization and user interface technologies have enabled development of "virtual reality" programs that allow users to perceive and to interact with objects in artificial three-dimensional environments. Such technologies were used to create an image database and program for studying the human skull, a specimen that has become increasingly expensive and scarce. Stereoscopic image pairs of a museum-quality skull were digitized from multiple views. For each view, the stereo pairs were interlaced into a single, field-sequential stereoscopic picture using an image processing program. The resulting interlaced image files are organized in an interactive multimedia program. At run-time, gray-scale 3-D images are displayed on a large-screen computer monitor and observed through liquid-crystal shutter goggles. Users can then control the program and change views with a mouse and cursor to point-and-click on screen-level control words ("buttons"). For each view of the skull, an ID control button can be used to overlay pointers and captions for important structures. Pointing and clicking on "hidden buttons" overlying certain structures triggers digitized audio spoken word descriptions or mini lectures. PMID:8793223

  8. Assessing the precision of gaze following using a stereoscopic 3D virtual reality setting.

    PubMed

    Atabaki, Artin; Marciniak, Karolina; Dicke, Peter W; Thier, Peter

    2015-07-01

    Despite the ecological importance of gaze following, little is known about the underlying neuronal processes, which allow us to extract gaze direction from the geometric features of the eye and head of a conspecific. In order to understand the neuronal mechanisms underlying this ability, a careful description of the capacity and the limitations of gaze following at the behavioral level is needed. Previous studies of gaze following, which relied on naturalistic settings have the disadvantage of allowing only very limited control of potentially relevant visual features guiding gaze following, such as the contrast of iris and sclera, the shape of the eyelids and--in the case of photographs--they lack depth. Hence, in order to get full control of potentially relevant features we decided to study gaze following of human observers guided by the gaze of a human avatar seen stereoscopically. To this end we established a stereoscopic 3D virtual reality setup, in which we tested human subjects' abilities to detect at which target a human avatar was looking at. Following the gaze of the avatar showed all the features of the gaze following of a natural person, namely a substantial degree of precision associated with a consistent pattern of systematic deviations from the target. Poor stereo vision affected performance surprisingly little (only in certain experimental conditions). Only gaze following guided by targets at larger downward eccentricities exhibited a differential effect of the presence or absence of accompanying movements of the avatar's eyelids and eyebrows. PMID:25982719

  9. Thermal 3D Modeling of Geothermal Area Using Terrestrial Photogrammetry

    NASA Astrophysics Data System (ADS)

    Akcay, Ozgun; Cuneyt Erenoglu, Ramazan; Erenoglu, Oya; Yılmazturk, Ferruh; Karaca, Zeki

    2015-04-01

    Photogrammetry and computer vision, sciences producing high accuracy 3D models from digital images based on projective geometry. 3D models can also be produced using thermal camera images using photogrammetry and computer vision techniques. Thermal images are capable of displaying hotspots on geothermal areas as a heat source in details. In the research, Tuzla geothermal area in Çanakkale province of Turkey is inspected using imaging techniques of terrestrial photogrammetry. Both a digital camera Canon EOS 650D and an infrared camera Optris PI 450 are used to obtain images of the thermal site. Calibration parameters (focal length, principle point, distortion coefficients) of thermal and digital cameras are determined using the calibration test field at the laboratory before the field work. In order to provide the georeferencing and the robustness of the 3D model, aluminum discs having diameter of 30 centimeters as ground control points (GCPs) are set to the geothermal area appropriately before imaging. Aluminum targets are chosen as the GCP because they are determined on the image depending on the contrast reflectance rate of the aluminum. Using GNSS RTK receivers supplying ±1 cm accuracy positioning, GCPs are measured so as to implement photogrammetric process successfully with thermal images. Numerous corresponding points are detected on the overlapped images with image matching techniques. Later on, bundle block adjustment is applied to calculate the revised interior orientation parameters of camera and exterior orientation parameters of camera positions. The 3D model showing details of the surface temperatures of the geothermal area are produced with multi view stereo (MVS) technique. The technique is able to produce 3D representation (point cloud, mesh and textured surface) of the field from both the thermal and digital images. The research presents that photogrammetric evaluation of thermal images is a noteworthy method to obtain a quick- accurate 3D

  10. 3D geometric modelling of hand-woven textile

    NASA Astrophysics Data System (ADS)

    Shidanshidi, H.; Naghdy, F.; Naghdy, G.; Conroy, D. Wood

    2008-02-01

    Geometric modeling and haptic rendering of textile has attracted significant interest over the last decade. A haptic representation is created by adding the physical properties of an object to its geometric configuration. While research has been conducted into geometric modeling of fabric, current systems require time-consuming manual recognition of textile specifications and data entry. The development of a generic approach for construction of the 3D geometric model of a woven textile is pursued in this work. The geometric model would be superimposed by a haptic model in the future work. The focus at this stage is on hand-woven textile artifacts for display in museums. A fuzzy rule based algorithm is applied to the still images of the artifacts to generate the 3D model. The derived model is exported as a 3D VRML model of the textile for visual representation and haptic rendering. An overview of the approach is provided and the developed algorithm is described. The approach is validated by applying the algorithm to different textile samples and comparing the produced models with the actual structure and pattern of the samples.

  11. A biochemical/biophysical 3D FE intervertebral disc model.

    PubMed

    Schroeder, Y; Huyghe, J M; van Donkelaar, C C; Ito, K

    2010-10-01

    Present research focuses on different strategies to preserve the degenerated disc. To assure long-term success of novel approaches, favorable mechanical conditions in the disc tissue are essential. To evaluate these, a model is required that can determine internal mechanical conditions which cannot be directly measured as a function of assessable biophysical characteristics. Therefore, the objective is to evaluate if constitutive and material laws acquired on isolated samples of nucleus and annulus tissue can be used directly in a whole-organ 3D FE model to describe intervertebral disc behavior. The 3D osmo-poro-visco-hyper-elastic disc (OVED) model describes disc behavior as a function of annulus and nucleus tissue biochemical composition, organization and specific constituent properties. The description of the 3D collagen network was enhanced to account for smaller fibril structures. Tissue mechanical behavior tests on isolated nucleus and annulus samples were simulated with models incorporating tissue composition to calculate the constituent parameter values. The obtained constitutive laws were incorporated into the whole-organ model. The overall behavior and disc properties of the model were corroborated against in vitro creep experiments of human L4/L5 discs. The OVED model simulated isolated tissue experiments on confined compression and uniaxial tensile test and whole-organ disc behavior. This was possible, provided that secondary fiber structures were accounted for. The fair agreement (radial bulge, axial creep deformation and intradiscal pressure) between model and experiment was obtained using constitutive properties that are the same for annulus and nucleus. Both tissue models differed in the 3D OVED model only by composition. The composition-based modeling presents the advantage of reducing the numbers of material parameters to a minimum and to use tissue composition directly as input. Hence, this approach provides the possibility to describe internal

  12. Use Models like Maps in a 3D SDI

    NASA Astrophysics Data System (ADS)

    Gietzel, Jan; Gabriel, Paul; Schaeben, Helmut; Le, Hai Ha

    2013-04-01

    Digital geological applications have become 3D up to 4D modelling of the underground. The modellers are working very heterogeneously in terms of its applied software systems. On the other hand the 3D/4D modelling of the subsurface has become part of the geological surveys all around the world. This implies a wide spread group of users working in different institutions aiming to work together on one subsurface model. Established 3D/4D-modelling software systems mainly use a file based approach to store data, which is in a high contrast to the needs of a central administrated and network based data transfer approach. At the department of geophysics and geo information sciences at the Technical University Bergakademie Freiberg, the GST system for managing 3D and 4D geosciences data in a databases system was developed and is now continued by the company GiGa infosystems. The GST-Framework includes a storage engine, a web service for sharing and a number of client software including a browser based client interface for visualising, accessing and manipulating geological CAD data. Including a check out system GST supports multi user editing on huge models, designed to manage seamless high resolution models of the subsurface. While working on complex projects various software is used for the creation of the model, the prediction of properties and final simulation. A problem rising from the use of several software is the interoperability of the models. Due to conversion errors different working groups use mainly different raw data. This results in different models, which have to be corrected with additional effort. One platform sharing the models is strongly demanded. One high potential solution is a centralized and software independent storage, which will be presented.

  13. Robust 3D reconstruction system for human jaw modeling

    NASA Astrophysics Data System (ADS)

    Yamany, Sameh M.; Farag, Aly A.; Tazman, David; Farman, Allan G.

    1999-03-01

    This paper presents a model-based vision system for dentistry that will replace traditional approaches used in diagnosis, treatment planning and surgical simulation. Dentistry requires accurate 3D representation of the teeth and jaws for many diagnostic and treatment purposes. For example orthodontic treatment involves the application of force systems to teeth over time to correct malocclusion. In order to evaluate tooth movement progress, the orthodontists monitors this movement by means of visual inspection, intraoral measurements, fabrication of plastic models, photographs and radiographs, a process which is both costly and time consuming. In this paper an integrate system has been developed to record the patient's occlusion using computer vision. Data is acquired with an intraoral video camera. A modified shape from shading (SFS) technique, using perspective projection and camera calibration, is used to extract accurate 3D information from a sequence of 2D images of the jaw. A new technique for 3D data registration, using a Grid Closest Point transform and genetic algorithms, is used to register the SFS output. Triangulization is then performed, and a solid 3D model is obtained via a rapid prototype machine.

  14. Validation of a Parametric Approach for 3d Fortification Modelling: Application to Scale Models

    NASA Astrophysics Data System (ADS)

    Jacquot, K.; Chevrier, C.; Halin, G.

    2013-02-01

    Parametric modelling approach applied to cultural heritage virtual representation is a field of research explored for years since it can address many limitations of digitising tools. For example, essential historical sources for fortification virtual reconstructions like plans-reliefs have several shortcomings when they are scanned. To overcome those problems, knowledge based-modelling can be used: knowledge models based on the analysis of theoretical literature of a specific domain such as bastioned fortification treatises can be the cornerstone of the creation of a parametric library of fortification components. Implemented in Grasshopper, these components are manually adjusted on the data available (i.e. 3D surveys of plans-reliefs or scanned maps). Most of the fortification area is now modelled and the question of accuracy assessment is raised. A specific method is used to evaluate the accuracy of the parametric components. The results of the assessment process will allow us to validate the parametric approach. The automation of the adjustment process can finally be planned. The virtual model of fortification is part of a larger project aimed at valorising and diffusing a very unique cultural heritage item: the collection of plans-reliefs. As such, knowledge models are precious assets when automation and semantic enhancements will be considered.

  15. 3D Geological modelling - towards a European level infrastructure

    NASA Astrophysics Data System (ADS)

    Lee, Kathryn A.; van der Krogt, Rob; Busschers, Freek S.

    2013-04-01

    The joint European Geological Surveys are preparing the ground for a "European Geological Data Infrastructure" (EGDI), under the framework of the FP7-project EGDI-Scope. This scoping study, started in June 2012, for a pan-European e-Infrastructure is based on the successes of earlier joint projects including 'OneGeology-Europe' and aims to provide the backbone for serving interoperable, geological data currently held by European Geological Surveys. Also data from past, ongoing and future European projects will be incorporated. The scope will include an investigation of the functional and technical requirements for serving 3D geological models and will look to research the potential for providing a framework to integrate models at different scales, and form a structure for enabling the development of new and innovative model delivery mechanisms. The EGDI-scope project encourages pan-European inter-disciplinary collaboration between all European Geological Surveys. It aims to enhance emerging web based technologies that will facilitate the delivery of geological data to user communities involved in European policy making and international industry, but also to geoscientific research communities and the general public. Therefore, stakeholder input and communication is imperative to the success, as is the collaboration with all the Geological Surveys of Europe. The most important functional and technical requirements for delivery of such information at pan-European level will be derived from exchanges with relevant European stakeholder representatives and providers of geological data. For handling and delivering 3D geological model data the project will need to address a number of strategic issues: • Which are the most important issues and queries for the relevant stakeholders, requiring 3D geological models? How can this be translated to functional requirements for development and design of an integrated European application? • How to handle the very large

  16. 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. At the end…

  17. 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…

  18. 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…

  19. Quasi-3D Multi-scale Modeling Framework Development

    NASA Astrophysics Data System (ADS)

    Arakawa, A.; Jung, J.

    2008-12-01

    When models are truncated in or near an energetically active range of the spectrum, model physics must be changed as the resolution changes. The model physics of GCMs and that of CRMs are, however, quite different from each other and at present there is no unified formulation of model physics that automatically provides transition between these model physics. The Quasi-3D (Q3D) Multi-scale Modeling Framework (MMF) is an attempt to bridge this gap. Like the recently proposed Heterogeneous Multiscale Method (HMM) (E and Engquist 2003), MMF combines a macroscopic model, GCM, and a microscopic model, CRM. Unlike the traditional multiscale methods such as the multi-grid and adapted mesh refinement techniques, HMM and MMF are for solving multi-physics problems. They share the common objective "to design combined macroscopic-microscopic computational methods that are much more efficient than solving the full microscopic model and at the same time give the information we need" (E et al. 2008). The question is then how to meet this objective in practice, which can be highly problem dependent. In HHM, the efficiency is gained typically by localization of the microscale problem. Following the pioneering work by Grabowski and Smolarkiewicz (1999) and Grabowski (2001), MMF takes advantage of the fact that 2D CRMs are reasonably successful in simulating deep clouds. In this approach, the efficiency is gained by sacrificing the three-dimensionality of cloud-scale motion. It also "localizes" the algorithm through embedding a CRM in each GCM grid box using cyclic boundary condition. The Q3D MMF is an attempt to reduce the expense due to these constraints by partially including the cloud-scale 3D effects and extending the CRM beyond individual GCM grid boxes. As currently formulated, the Q3D MMF is a 4D estimation/prediction framework that combines a GCM with a 3D anelastic cloud-resolving vector vorticity equation model (VVM) applied to a network of horizontal grids. The network

  20. 3-D HYDRODYNAMIC MODELING IN A GEOSPATIAL FRAMEWORK

    SciTech Connect

    Bollinger, J; Alfred Garrett, A; Larry Koffman, L; David Hayes, D

    2006-08-24

    3-D hydrodynamic models are used by the Savannah River National Laboratory (SRNL) to simulate the transport of thermal and radionuclide discharges in coastal estuary systems. Development of such models requires accurate bathymetry, coastline, and boundary condition data in conjunction with the ability to rapidly discretize model domains and interpolate the required geospatial data onto the domain. To facilitate rapid and accurate hydrodynamic model development, SRNL has developed a pre- and post-processor application in a geospatial framework to automate the creation of models using existing data. This automated capability allows development of very detailed models to maximize exploitation of available surface water radionuclide sample data and thermal imagery.

  1. 3D model of the Bernese Part of the Swiss Molasse Basin: visualization of uncertainties in a 3D model

    NASA Astrophysics Data System (ADS)

    Mock, Samuel; Allenbach, Robin; Reynolds, Lance; Wehrens, Philip; Kurmann-Matzenauer, Eva; Kuhn, Pascal; Michael, Salomè; Di Tommaso, Gennaro; Herwegh, Marco

    2016-04-01

    The Swiss Molasse Basin comprises the western and central part of the North Alpine Foreland Basin. In recent years it has come under closer scrutiny due to its promising geopotentials such as geothermal energy and CO2 sequestration. In order to adress these topics good knowledge of the subsurface is a key prerequisite. For that matter, geological 3D models serve as valuable tools. In collaboration with the Swiss Geological Survey (swisstopo) and as part of the project GeoMol CH, a geological 3D model of the Swiss Molasse Basin in the Canton of Bern has been built. The model covers an area of 1810 km2and reaches depth of up to 6.7 km. It comprises 10 major Cenozoic and Mesozoic units and numerous faults. The 3D model is mainly based on 2D seismic data complemented by information from few deep wells. Additionally, data from geological maps and profiles were used for refinement at shallow depths. In total, 1163 km of reflection seismic data, along 77 seismic lines, have been interpreted by different authors with respect to stratigraphy and structures. Both, horizons and faults, have been interpreted in 2D and modelled in 3D using IHS's Kingdom Suite and Midland Valley's MOVE software packages, respectively. Given the variable degree of subsurface information available, each 3D model is subject of uncertainty. With the primary input data coming from interpretation of reflection seismic data, a variety of uncertainties comes into play. Some of them are difficult to address (e.g. author's style of interpretation) while others can be quantified (e.g. mis-tie correction, well-tie). An important source of uncertainties is the quality of seismic data; this affects the traceability and lateral continuation of seismic reflectors. By defining quality classes we can semi-quantify this source of uncertainty. In order to visualize the quality and density of the input data in a meaningful way, we introduce quality-weighted data density maps. In combination with the geological 3D

  2. A method for building 3D models of barchan dunes

    NASA Astrophysics Data System (ADS)

    Nai, Yang; Li-lan, Su; Lin, Wan; Jie, Yang; Shi-yi, Chen; Wei-lu, Hu

    2016-01-01

    The distributions of barchan dunes are usually represented by digital terrain models (DTMs) overlaid with digital orthophoto maps. Given that most regions with barchan dues have low relief, a 3D map obtained from a DTM may ineffectively show the stereoscopic shape of each dune. The method of building 3D models of barchan dunes using existing modeling software seldom considers the geographical environment. As a result, barchan dune models are often inconsistent with actual DTMs and incompletely express the morphological characteristics of dunes. Manual construction of barchan dune models is also costly and time consuming. Considering these problems, the morphological characteristics of barchan dunes and the mathematical relationships between the morphological parameters of the dunes, such as length, height, and width, are analyzed in this study. The methods of extracting the morphological feature points of barchan dunes, calculating their morphological parameters and building dune outlines and skeleton lines based on the medial axes, are also presented. The dune outlines, skeleton lines, and part of the medial axes of dunes are used to construct a constrained triangulated irregular network. C# and ArcEngine are employed to build 3D models of barchan dunes automatically. Experimental results of a study conducted in Tengger Desert show that the method can be used to approximate the morphological characteristics of barchan dunes and is less time consuming than manual methods.

  3. Geometric and colour data fusion for outdoor 3D models.

    PubMed

    Merchán, Pilar; Adán, Antonio; Salamanca, Santiago; Domínguez, Vicente; Chacón, Ricardo

    2012-01-01

    This paper deals with the generation of accurate, dense and coloured 3D models of outdoor scenarios from scanners. This is a challenging research field in which several problems still remain unsolved. In particular, the process of 3D model creation in outdoor scenes may be inefficient if the scene is digitalized under unsuitable technical (specific scanner on-board camera) and environmental (rain, dampness, changing illumination) conditions. We address our research towards the integration of images and range data to produce photorealistic models. Our proposal is based on decoupling the colour integration and geometry reconstruction stages, making them independent and controlled processes. This issue is approached from two different viewpoints. On the one hand, given a complete model (geometry plus texture), we propose a method to modify the original texture provided by the scanner on-board camera with the colour information extracted from external images taken at given moments and under specific environmental conditions. On the other hand, we propose an algorithm to directly assign external images onto the complete geometric model, thus avoiding tedious on-line calibration processes. We present the work conducted on two large Roman archaeological sites dating from the first century A.D., namely, the Theatre of Segobriga and the Fori Porticus of Emerita Augusta, both in Spain. The results obtained demonstrate that our approach could be useful in the digitalization and 3D modelling fields. PMID:22969327

  4. 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.

  5. Towards a 3d Spatial Urban Energy Modelling Approach

    NASA Astrophysics Data System (ADS)

    Bahu, J.-M.; Koch, A.; Kremers, E.; Murshed, S. M.

    2013-09-01

    Today's needs to reduce the environmental impact of energy use impose dramatic changes for energy infrastructure and existing demand patterns (e.g. buildings) corresponding to their specific context. In addition, future energy systems are expected to integrate a considerable share of fluctuating power sources and equally a high share of distributed generation of electricity. Energy system models capable of describing such future systems and allowing the simulation of the impact of these developments thus require a spatial representation in order to reflect the local context and the boundary conditions. This paper describes two recent research approaches developed at EIFER in the fields of (a) geo-localised simulation of heat energy demand in cities based on 3D morphological data and (b) spatially explicit Agent-Based Models (ABM) for the simulation of smart grids. 3D city models were used to assess solar potential and heat energy demand of residential buildings which enable cities to target the building refurbishment potentials. Distributed energy systems require innovative modelling techniques where individual components are represented and can interact. With this approach, several smart grid demonstrators were simulated, where heterogeneous models are spatially represented. Coupling 3D geodata with energy system ABMs holds different advantages for both approaches. On one hand, energy system models can be enhanced with high resolution data from 3D city models and their semantic relations. Furthermore, they allow for spatial analysis and visualisation of the results, with emphasis on spatially and structurally correlations among the different layers (e.g. infrastructure, buildings, administrative zones) to provide an integrated approach. On the other hand, 3D models can benefit from more detailed system description of energy infrastructure, representing dynamic phenomena and high resolution models for energy use at component level. The proposed modelling strategies

  6. 3-D model-based tracking for UAV indoor localization.

    PubMed

    Teulière, Céline; Marchand, Eric; Eck, Laurent

    2015-05-01

    This paper proposes a novel model-based tracking approach for 3-D localization. One main difficulty of standard model-based approach lies in the presence of low-level ambiguities between different edges. In this paper, given a 3-D model of the edges of the environment, we derive a multiple hypotheses tracker which retrieves the potential poses of the camera from the observations in the image. We also show how these candidate poses can be integrated into a particle filtering framework to guide the particle set toward the peaks of the distribution. Motivated by the UAV indoor localization problem where GPS signal is not available, we validate the algorithm on real image sequences from UAV flights. PMID:25099967

  7. 3D Babcock-Leighton Solar Dynamo Models

    NASA Astrophysics Data System (ADS)

    Miesch, Mark S.; Hazra, Gopal; Karak, Bidya Binay; Teweldebirhan, Kinfe; Upton, Lisa

    2016-05-01

    We present results from the new STABLE (Surface flux Transport and Babcock Leighton) Dynamo Model. STABLE is a 3D Babcock-Leighton/Flux Transport dynamo model in which the source of poloidal field is the explicit emergence, distortion, and dispersal of bipolar magnetic regions (BMRs). In this talk I will discuss initial results with axisymmetric flow fields, focusing on the operation of the model, the general features of the cyclic solutions, and the challenge of achieving supercritical dynamo solutions using only the Babcock-Leighton source term. Then I will present dynamo simulations that include 3D convective flow fields based on the observed velocity power spectrum inferred from photospheric Dopplergrams. I'll use these simulations to assess how the explicit transport and amplification of fields by surface convection influences the operation of the dynamo. I will also discuss the role of surface magnetic fields in regulating the subsurface toroidal flux budget.

  8. 3D Multispectral Light Propagation Model For Subcutaneous Veins Imaging

    SciTech Connect

    Paquit, Vincent C; Price, Jeffery R; Meriaudeau, Fabrice; Tobin Jr, Kenneth William

    2008-01-01

    In this paper, we describe a new 3D light propagation model aimed at understanding the effects of various physiological properties on subcutaneous vein imaging. In particular, we build upon the well known MCML (Monte Carlo Multi Layer) code and present a tissue model that improves upon the current state-of-the-art by: incorporating physiological variation, such as melanin concentration, fat content, and layer thickness; including veins of varying depth and diameter; using curved surfaces from real arm shapes; and modeling the vessel wall interface. We describe our model, present results from the Monte Carlo modeling, and compare these results with those obtained with other Monte Carlo methods.

  9. Texture blending on 3D models using casual images

    NASA Astrophysics Data System (ADS)

    Liu, Xingming; Liu, Xiaoli; Li, Ameng; Liu, Junyao; Wang, Huijing

    2013-12-01

    In this paper, a method for constructing photorealistic textured model using 3D structured light digitizer is presented. Our method acquisition of range images and texture images around object, and range images are registered and integrated to construct geometric model of object. System is calibrated and poses of texture-camera are determined so that the relationship between texture and geometric model is established. After that, a global optimization is applied to assign compatible texture to adjacent surface and followed with a level procedure to remove artifacts due to vary lighting, approximate geometric model and so on. Lastly, we demonstrate the effect of our method on constructing a real model of world.

  10. A 3D alcoholic liver disease model on a chip.

    PubMed

    Lee, JaeSeo; Choi, BongHwan; No, Da Yoon; Lee, GeonHui; Lee, Seung-Ri; Oh, HyunJik; Lee, Sang-Hoon

    2016-03-14

    Alcohol is one of the main causes of liver diseases, and the development of alcoholic liver disease (ALD) treatment methods has been one of the hottest issues. For this purpose, development of in vitro models mimicking the in vivo physiology is one of the critical requirements, and they help to determine the disease mechanisms and to discover the treatment method. Herein, a three-dimensional (3D) ALD model was developed and its superior features in mimicking the in vivo condition were demonstrated. A spheroid-based microfluidic chip was employed for the development of the 3D in vitro model of ALD progression. We co-cultured rat primary hepatocytes and hepatic stellate cells (HSCs) in a fluidic chip to investigate the role of HSCs in the recovery of liver with ALD. An interstitial level of flow derived by an osmotic pump was applied to the chip to provide in vivo mimicking of fluid activity. Using this in vitro tool, we were able to observe structural changes and decreased hepatic functions with the increase in ethanol concentration. The recovery process of liver injured by alcohol was observed by providing fresh culture medium to the damaged 3D liver tissue for few days. A reversibly- and irreversibly-injured ALD model was established. The proposed model can not only be used for the research of alcoholic disease mechanism, but also has the potential for use in studies of hepatotoxicity and drug screening applications. PMID:26857817

  11. Two-equation turbulence modeling for 3-D hypersonic flows

    NASA Technical Reports Server (NTRS)

    Bardina, J. E.; Coakley, T. J.; Marvin, J. G.

    1992-01-01

    An investigation to verify, incorporate and develop two-equation turbulence models for three-dimensional high speed flows is presented. The current design effort of hypersonic vehicles has led to an intensive study of turbulence models for compressible hypersonic flows. This research complements an extensive review of experimental data and the current development of 2D turbulence models. The review of experimental data on 2D and 3D flows includes complex hypersonic flows with pressure profiles, skin friction, wall heat transfer, and turbulence statistics data. In a parallel effort, turbulence models for high speed flows have been tested against flat plate boundary layers, and are being tested against the 2D database. In the present paper, we present the results of 3D Navier-Stokes numerical simulations with an improved k-omega two-equation turbulence model against experimental data and empirical correlations of an adiabatic flat plate boundary layer, a cold wall flat plate boundary layer, and a 3D database flow, the interaction of an oblique shock wave and a thick turbulent boundary layer with a free stream Mach number = 8.18 and Reynolds number = 5 x 10 to the 6th.

  12. Generation and use of human 3D-CAD models

    NASA Astrophysics Data System (ADS)

    Grotepass, Juergen; Speyer, Hartmut; Kaiser, Ralf

    2002-05-01

    Individualized Products are one of the ten mega trends of the 21st Century with human modeling as the key issue for tomorrow's design and product development. The use of human modeling software for computer based ergonomic simulations within the production process increases quality while reducing costs by 30- 50 percent and shortening production time. This presentation focuses on the use of human 3D-CAD models for both, the ergonomic design of working environments and made to measure garment production. Today, the entire production chain can be designed, individualized models generated and analyzed in 3D computer environments. Anthropometric design for ergonomics is matched to human needs, thus preserving health. Ergonomic simulation includes topics as human vision, reachability, kinematics, force and comfort analysis and international design capabilities. In German more than 17 billions of Mark are moved to other industries, because clothes do not fit. Individual clothing tailored to the customer's preference means surplus value, pleasure and perfect fit. The body scanning technology is the key to generation and use of human 3D-CAD models for both, the ergonomic design of working environments and made to measure garment production.

  13. 3D cartographic modeling of the Alpine arc

    NASA Astrophysics Data System (ADS)

    Vouillamoz, Naomi; Sue, Christian; Champagnac, Jean-Daniel; Calcagno, Philippe

    2012-12-01

    We built a 3D cartography of the Alpine arc, a highly non-cylindrical mountain belt, using the 3D GeoModeller of the BRGM (French geological survey). The model allows to handle the large-scale 3D structure of seventeen major crustal units of the belt (from the lower crust to the sedimentary cover nappes), and two main discontinuities (the Insubric Line and the Crustal Penninic Front). It provides a unique document to better understand their structural relationships and to produce new sections. The study area comprises the western Alpine arc, from the Jura to the Northwest, up to the Bergell granite intrusion and the Lepontine Dome to the East, and is limited to the South by the Ligurian basin. The model is limited vertically 10 km above sea level at the top, and the moho interface at the bottom. We discarded the structural relationships between the Alps sensus stricto and the surrounding geodynamic systems such as the Rhine graben or the connection with the Apennines. The 3D-model is based on the global integration of various data such as the DEM of the Alps, the moho isobaths, the simplified geological and tectonic maps of the belt, the crustal cross-sections ECORS-CROP and NFP-20, and complementary cross-sections specifically built to precise local complexities. The database has first been integrated in a GIS-project to prepare their implementation in the GeoModeller, by homogenizing the different spatial referencing systems. The global model is finally interpolated from all these data, using the potential field method. The final document is a new tri-dimensional cartography that would be used as input for further alpine studies.

  14. 3D modeling of dual-gate FinFET.

    PubMed

    Mil'shtein, Samson; Devarakonda, Lalitha; Zanchi, Brian; Palma, John

    2012-01-01

    The tendency to have better control of the flow of electrons in a channel of field-effect transistors (FETs) did lead to the design of two gates in junction field-effect transistors, field plates in a variety of metal semiconductor field-effect transistors and high electron mobility transistors, and finally a gate wrapping around three sides of a narrow fin-shaped channel in a FinFET. With the enhanced control, performance trends of all FETs are still challenged by carrier mobility dependence on the strengths of the electrical field along the channel. However, in cases when the ratio of FinFET volume to its surface dramatically decreases, one should carefully consider the surface boundary conditions of the device. Moreover, the inherent non-planar nature of a FinFET demands 3D modeling for accurate analysis of the device performance. Using the Silvaco modeling tool with quantization effects, we modeled a physical FinFET described in the work of Hisamoto et al. (IEEE Tran. Elec. Devices 47:12, 2000) in 3D. We compared it with a 2D model of the same device. We demonstrated that 3D modeling produces more accurate results. As 3D modeling results came close to experimental measurements, we made the next step of the study by designing a dual-gate FinFET biased at Vg1 >Vg2. It is shown that the dual-gate FinFET carries higher transconductance than the single-gate device. PMID:23148493

  15. Visuomotor learning in immersive 3D virtual reality in Parkinson's disease and in aging.

    PubMed

    Messier, Julie; Adamovich, Sergei; Jack, David; Hening, Wayne; Sage, Jacob; Poizner, Howard

    2007-05-01

    Successful adaptation to novel sensorimotor contexts critically depends on efficient sensory processing and integration mechanisms, particularly those required to combine visual and proprioceptive inputs. If the basal ganglia are a critical part of specialized circuits that adapt motor behavior to new sensorimotor contexts, then patients who are suffering from basal ganglia dysfunction, as in Parkinson's disease should show sensorimotor learning impairments. However, this issue has been under-explored. We tested the ability of 8 patients with Parkinson's disease (PD), off medication, ten healthy elderly subjects and ten healthy young adults to reach to a remembered 3D location presented in an immersive virtual environment. A multi-phase learning paradigm was used having four conditions: baseline, initial learning, reversal learning and aftereffect. In initial learning, the computer altered the position of a simulated arm endpoint used for movement feedback by shifting its apparent location diagonally, requiring thereby both horizontal and vertical compensations. This visual distortion forced subjects to learn new coordinations between what they saw in the virtual environment and the actual position of their limbs, which they had to derive from proprioceptive information (or efference copy). In reversal learning, the sign of the distortion was reversed. Both elderly subjects and PD patients showed learning phase-dependent difficulties. First, elderly controls were slower than young subjects when learning both dimensions of the initial biaxial discordance. However, their performance improved during reversal learning and as a result elderly and young controls showed similar adaptation rates during reversal learning. Second, in striking contrast to healthy elderly subjects, PD patients were more profoundly impaired during the reversal phase of learning. PD patients were able to learn the initial biaxial discordance but were on average slower than age-matched controls

  16. 3D chromosome rendering from Hi-C data using virtual reality

    NASA Astrophysics Data System (ADS)

    Zhu, Yixin; Selvaraj, Siddarth; Weber, Philip; Fang, Jennifer; Schulze, Jürgen P.; Ren, Bing

    2015-01-01

    Most genome browsers display DNA linearly, using single-dimensional depictions that are useful to examine certain epigenetic mechanisms such as DNA methylation. However, these representations are insufficient to visualize intrachromosomal interactions and relationships between distal genome features. Relationships between DNA regions may be difficult to decipher or missed entirely if those regions are distant in one dimension but could be spatially proximal when mapped to three-dimensional space. For example, the visualization of enhancers folding over genes is only fully expressed in three-dimensional space. Thus, to accurately understand DNA behavior during gene expression, a means to model chromosomes is essential. Using coordinates generated from Hi-C interaction frequency data, we have created interactive 3D models of whole chromosome structures and its respective domains. We have also rendered information on genomic features such as genes, CTCF binding sites, and enhancers. The goal of this article is to present the procedure, findings, and conclusions of our models and renderings.

  17. Magnetic resonance virtual histology for embryos: 3D atlases for automated high-throughput phenotyping.

    PubMed

    Cleary, Jon O; Modat, Marc; Norris, Francesca C; Price, Anthony N; Jayakody, Sujatha A; Martinez-Barbera, Juan Pedro; Greene, Nicholas D E; Hawkes, David J; Ordidge, Roger J; Scambler, Peter J; Ourselin, Sebastien; Lythgoe, Mark F

    2011-01-15

    Ambitious international efforts are underway to produce gene-knockout mice for each of the 25,000 mouse genes, providing a new platform to study mammalian development and disease. Robust, large-scale methods for morphological assessment of prenatal mice will be essential to this work. Embryo phenotyping currently relies on histological techniques but these are not well suited to large volume screening. The qualitative nature of these approaches also limits the potential for detailed group analysis. Advances in non-invasive imaging techniques such as magnetic resonance imaging (MRI) may surmount these barriers. We present a high-throughput approach to generate detailed virtual histology of the whole embryo, combined with the novel use of a whole-embryo atlas for automated phenotypic assessment. Using individual 3D embryo MRI histology, we identified new pituitary phenotypes in Hesx1 mutant mice. Subsequently, we used advanced computational techniques to produce a whole-body embryo atlas from 6 CD-1 embryos, creating an average image with greatly enhanced anatomical detail, particularly in CNS structures. This methodology enabled unsupervised assessment of morphological differences between CD-1 embryos and Chd7 knockout mice (n=5 Chd7(+/+) and n=8 Chd7(+/-), C57BL/6 background). Using a new atlas generated from these three groups, quantitative organ volumes were automatically measured. We demonstrated a difference in mean brain volumes between Chd7(+/+) and Chd7(+/-) mice (42.0 vs. 39.1mm(3), p<0.05). Differences in whole-body, olfactory and normalised pituitary gland volumes were also found between CD-1 and Chd7(+/+) mice (C57BL/6 background). Our work demonstrates the feasibility of combining high-throughput embryo MRI with automated analysis techniques to distinguish novel mouse phenotypes. PMID:20656039

  18. Interchain coupling and 3D modeling of trans-polyacetylene

    SciTech Connect

    Bronold, F.; Saxena, A.; Bishop, A.R.

    1992-01-01

    In spite of the success of the SSH model for trans-polyacetylene in interpreting many experimental results (e.g. optical and magnetic properties) there remain some aspects of the real material which are outside the scope of the simple 1D model. Especially ordering phenomena of doped and undoped trans-polyacetylene as well as transport properties (e.g. electronic and thermal conductivity) are beyond a 1D description. There are many attempts to construct a transport theory for this novel class of materials using solitons or polaxons as the basic ingredients. But so far it is not yet clear whether these typical 1D excitations still exist in crystalline transpolyacetylene. Therefore, to clarify the role which intrinsic self-localized nonlinear excitations characteristic of 1D models play in the bulk (3D) material, we study the stability of a polaronic excitation against interchain coupling. As a preliminary step we consider first two coupled t-(CH){sub x}-chains where the {pi}-electrons are allowed to hop from one chain to the other. Then we introduce a 3D generalization of the SSH model and study a polaron in a 3D crystalline environment.

  19. Interchain coupling and 3D modeling of trans-polyacetylene

    SciTech Connect

    Bronold, F.; Saxena, A.; Bishop, A.R.

    1992-09-01

    In spite of the success of the SSH model for trans-polyacetylene in interpreting many experimental results (e.g. optical and magnetic properties) there remain some aspects of the real material which are outside the scope of the simple 1D model. Especially ordering phenomena of doped and undoped trans-polyacetylene as well as transport properties (e.g. electronic and thermal conductivity) are beyond a 1D description. There are many attempts to construct a transport theory for this novel class of materials using solitons or polaxons as the basic ingredients. But so far it is not yet clear whether these typical 1D excitations still exist in crystalline transpolyacetylene. Therefore, to clarify the role which intrinsic self-localized nonlinear excitations characteristic of 1D models play in the bulk (3D) material, we study the stability of a polaronic excitation against interchain coupling. As a preliminary step we consider first two coupled t-(CH){sub x}-chains where the {pi}-electrons are allowed to hop from one chain to the other. Then we introduce a 3D generalization of the SSH model and study a polaron in a 3D crystalline environment.

  20. The 3D model control of image processing

    NASA Technical Reports Server (NTRS)

    Nguyen, An H.; Stark, Lawrence

    1989-01-01

    Telerobotics studies remote control of distant robots by a human operator using supervisory or direct control. Even if the robot manipulators has vision or other senses, problems arise involving control, communications, and delay. The communication delays that may be expected with telerobots working in space stations while being controlled from an Earth lab have led to a number of experiments attempting to circumvent the problem. This delay in communication is a main motivating factor in moving from well understood instantaneous hands-on manual control to less well understood supervisory control; the ultimate step would be the realization of a fully autonomous robot. The 3-D model control plays a crucial role in resolving many conflicting image processing problems that are inherent in resolving in the bottom-up approach of most current machine vision processes. The 3-D model control approach is also capable of providing the necessary visual feedback information for both the control algorithms and for the human operator.

  1. 3D root canal modeling for advanced endodontic treatment

    NASA Astrophysics Data System (ADS)

    Hong, Shane Y.; Dong, Janet

    2002-06-01

    More than 14 million teeth receive endodontic (root canal) treatment annually. Before a clinician's inspection and diagnosis, destructive access preparation by removing teeth crown and dentin is usually needed. This paper presents a non-invasive method for accessing internal tooth geometry by building 3-D tooth model from 2-D radiographic and endoscopic images to be used for an automatic prescription system of computer-aided treatment procedure planning, and for the root canal preparation by an intelligent micro drilling machine with on-line monitoring. It covers the techniques specific for dental application in the radiographic images acquirement, image enhancement, image segmentation and feature recognition, distance measurement and calibration, merging 2D image into 3D mathematical model representation and display. Included also are the methods to form references for irregular teeth geometry and to do accurately measurement with self-calibration.

  2. Modeling 3D faces from samplings via compressive sensing

    NASA Astrophysics Data System (ADS)

    Sun, Qi; Tang, Yanlong; Hu, Ping

    2013-07-01

    3D data is easier to acquire for family entertainment purpose today because of the mass-production, cheapness and portability of domestic RGBD sensors, e.g., Microsoft Kinect. However, the accuracy of facial modeling is affected by the roughness and instability of the raw input data from such sensors. To overcome this problem, we introduce compressive sensing (CS) method to build a novel 3D super-resolution scheme to reconstruct high-resolution facial models from rough samples captured by Kinect. Unlike the simple frame fusion super-resolution method, this approach aims to acquire compressed samples for storage before a high-resolution image is produced. In this scheme, depth frames are firstly captured and then each of them is measured into compressed samples using sparse coding. Next, the samples are fused to produce an optimal one and finally a high-resolution image is recovered from the fused sample. This framework is able to recover 3D facial model of a given user from compressed simples and this can reducing storage space as well as measurement cost in future devices e.g., single-pixel depth cameras. Hence, this work can potentially be applied into future applications, such as access control system using face recognition, and smart phones with depth cameras, which need high resolution and little measure time.

  3. Special Section: New Ways to Detect Colon Cancer 3-D virtual screening now being used

    MedlinePlus

    ... tech medical fields of biomedical visualization, computer graphics, virtual reality, and multimedia. The year was 1994. Kaufman's "two- ... organ, like the colon—and view it in virtual reality." Later, he and his team used it with ...

  4. 3D modelling of the Black Sea ecosystem

    NASA Astrophysics Data System (ADS)

    Capet, A.; Gregoire, M.; Beckers, J.-M.; Joassin, P.; Naithani, J.; Soetart, K.

    2009-04-01

    A coupled physical-biogeochemical model has been developed to simulate the ecosystem of the Black Sea at the end of the 80's when eutrophication and invasion by gelatinous organisms seriously affected the stability and dynamics of the system. The biogeochemical model describes the cycle of carbon, nitrogen, silicate, oxygen and phosphorus through the foodweb from bacteria to gelatinous carnivores and explicitly represents processes in the anoxic layer down to the bottom. For calibration and analyses purposes, the coupled model has first been run in 1D at several places in the Black Sea. The biogeochemical model involves some hundred parameters which have been first calibrated by hand using published values. Then, an identifiability analysis has been performed in order to determine a subset of 15 identifiable parameters. An automatic calibration subroutine has been used to fine tune these parameters. In 1D, the model solution exhibits a complex dynamics with several years of transient adjustment. This complexity is imparted by the explicit modelling of top predators. The model has been calibrated and validated using a large set of data available in the Black Sea TU Ocean Base. The calibrated biogeochemical model is implemented in a 3D hydrodynamical model of the Black Sea. Results of these 3D simulations will be presented and compared with maps of in-situ data reconstructed from available data base using the software DIVA (Data Interpolation and Variational analysis).

  5. 2D quantum double models from a 3D perspective

    NASA Astrophysics Data System (ADS)

    Bernabé Ferreira, Miguel Jorge; Padmanabhan, Pramod; Teotonio-Sobrinho, Paulo

    2014-09-01

    In this paper we look at three dimensional (3D) lattice models that are generalizations of the state sum model used to define the Kuperberg invariant of 3-manifolds. The partition function is a scalar constructed as a tensor network where the building blocks are tensors given by the structure constants of an involutory Hopf algebra A. These models are very general and are hard to solve in its entire parameter space. One can obtain familiar models, such as ordinary gauge theories, by letting A be the group algebra {C}(G) of a discrete group G and staying on a certain region of the parameter space. We consider the transfer matrix of the model and show that quantum double Hamiltonians are derived from a particular choice of the parameters. Such a construction naturally leads to the star and plaquette operators of the quantum double Hamiltonians, of which the toric code is a special case when A={C}({{{Z}}_{2}}). This formulation is convenient to study ground states of these generalized quantum double models where they can naturally be interpreted as tensor network states. For a surface Σ, the ground state degeneracy is determined by the Kuperberg 3-manifold invariant of \\Sigma \\times {{S}^{1}}. It is also possible to obtain extra models by simply enlarging the allowed parameter space but keeping the solubility of the model. While some of these extra models have appeared before in the literature, our 3D perspective allows for an uniform description of them.

  6. West Flank Coso, CA FORGE 3D geologic model

    DOE Data Explorer

    Doug Blankenship

    2016-03-01

    This is an x,y,z file of the West Flank FORGE 3D geologic model. Model created in Earthvision by Dynamic Graphic Inc. The model was constructed with a grid spacing of 100 m. Geologic surfaces were extrapolated from the input data using a minimum tension gridding algorithm. The data file is tabular data in a text file, with lithology data associated with X,Y,Z grid points. All the relevant information is in the file header (the spatial reference, the projection etc.) In addition all the fields in the data file are identified in the header.

  7. Right approach to 3D modeling using CAD tools

    NASA Astrophysics Data System (ADS)

    Baddam, Mounica Reddy

    The thesis provides a step-by-step methodology to enable an instructor dealing with CAD tools to optimally guide his/her students through an understandable 3D modeling approach which will not only enhance their knowledge about the tool's usage but also enable them to achieve their desired result in comparatively lesser time. In the known practical field, there is particularly very little information available to apply CAD skills to formal beginners' training sessions. Additionally, advent of new software in 3D domain cumulates updating into a more difficult task. Keeping up to the industry's advanced requirements emphasizes the importance of more skilled hands in the field of CAD development, rather than just prioritizing manufacturing in terms of complex software features. The thesis analyses different 3D modeling approaches specified to the varieties of CAD tools currently available in the market. Utilizing performance-time databases, learning curves have been generated to measure their performance time, feature count etc. Based on the results, improvement parameters have also been provided for (Asperl, 2005).

  8. Effective 3-D surface modeling for geographic information systems

    NASA Astrophysics Data System (ADS)

    Yüksek, K.; Alparslan, M.; Mendi, E.

    2013-11-01

    In this work, we propose a dynamic, flexible and interactive urban digital terrain platform (DTP) with spatial data and query processing capabilities of Geographic Information Systems (GIS), multimedia database functionality and graphical modeling infrastructure. A new data element, called Geo-Node, which stores image, spatial data and 3-D CAD objects is developed using an efficient data structure. The system effectively handles data transfer of Geo-Nodes between main memory and secondary storage with an optimized Directional Replacement Policy (DRP) based buffer management scheme. Polyhedron structures are used in Digital Surface Modeling (DSM) and smoothing process is performed by interpolation. The experimental results show that our framework achieves high performance and works effectively with urban scenes independent from the amount of spatial data and image size. The proposed platform may contribute to the development of various applications such as Web GIS systems based on 3-D graphics standards (e.g. X3-D and VRML) and services which integrate multi-dimensional spatial information and satellite/aerial imagery.

  9. Northern California Seismic Attenuation: 3-D Qp and Qs models

    NASA Astrophysics Data System (ADS)

    Eberhart-Phillips, D. M.

    2015-12-01

    The northern California crust exhibits a wide range of rock types and deformation processes which produce pronounced heterogeneity in regional attenuation. Using local earthquakes, 3-D Qp and Qs crustal models have been obtained for this region which includes the San Andreas fault system, the Central Valley, the Sierra Nevada batholith, and the Mendocino subduction volcanic system. Path attenuation t* values were determined from P and S spectra of 959 spatially distributed earthquakes, magnitude 2.5-6.0 from 2005-2014, using 1254 stations from NCEDC networks and IRIS Mendocino and Sierra Nevada temporary arrays. The t* data were used in Q inversions, using existing hypocenters and 3-D velocity models, with basic 10-km node spacing. The uneven data coverage was accounted for with linking of nodes into larger areas in order to provide useful Q images across the 3-D volume. The results at shallow depth (< 2 km) show very low Q in the Sacramento Delta, the Eureka area, and parts of the Bay Area. In the brittle crust, fault zones that have high seismicity exhibit low Q. In the lower crust, low Q is observed along fault zones that have large cumulative displacement and have experienced grain size reduction. Underlying active volcanic areas, low Q features are apparent below 20-km depth. Moderately high Q is associated with igneous rocks of the Sierra Nevada and Salinian block, while the Franciscan subduction complex shows moderately low Q. The most prominent high Q feature is related to the Great Valley Ophiolite.

  10. Effective 3-D surface modeling for geographic information systems

    NASA Astrophysics Data System (ADS)

    Yüksek, K.; Alparslan, M.; Mendi, E.

    2016-01-01

    In this work, we propose a dynamic, flexible and interactive urban digital terrain platform with spatial data and query processing capabilities of geographic information systems, multimedia database functionality and graphical modeling infrastructure. A new data element, called Geo-Node, which stores image, spatial data and 3-D CAD objects is developed using an efficient data structure. The system effectively handles data transfer of Geo-Nodes between main memory and secondary storage with an optimized directional replacement policy (DRP) based buffer management scheme. Polyhedron structures are used in digital surface modeling and smoothing process is performed by interpolation. The experimental results show that our framework achieves high performance and works effectively with urban scenes independent from the amount of spatial data and image size. The proposed platform may contribute to the development of various applications such as Web GIS systems based on 3-D graphics standards (e.g., X3-D and VRML) and services which integrate multi-dimensional spatial information and satellite/aerial imagery.

  11. Vasculogenesis and angiogenesis in the first trimester human placenta: an innovative 3D study using an immersive Virtual Reality system.

    PubMed

    van Oppenraaij, R H F; Koning, A H J; Lisman, B A; Boer, K; van den Hoff, M J B; van der Spek, P J; Steegers, E A P; Exalto, N

    2009-03-01

    First trimester human villous vascularization is mainly studied by conventional two-dimensional (2D) microscopy. With this (2D) technique it is not possible to observe the spatial arrangement of the haemangioblastic cords and vessels, transition of cords into vessels and the transition of vasculogenesis to angiogenesis. The Confocal Laser Scanning Microscopy (CLSM) allows for a three-dimensional (3D) reconstruction of images of early pregnancy villous vascularization. These 3D reconstructions, however, are normally analyzed on a 2D medium, lacking depth perception. We performed a descriptive morphologic study, using an immersive Virtual Reality system to utilize the full third dimension completely. This innovative 3D technique visualizes 3D datasets as enlarged 3D holograms and provided detailed insight in the spatial arrangement of first trimester villous vascularization, the beginning of lumen formation within various junctions of haemangioblastic cords between 5 and 7 weeks gestational age and in the gradual transition of vasculogenesis to angiogenesis. This innovative immersive Virtual Reality system enables new perspectives for vascular research and will be implemented for future investigation. PMID:19185915

  12. 3D Geologic Model of the San Diego Area

    NASA Astrophysics Data System (ADS)

    Danskin, W. R.; Cromwell, G.; Glockhoff, C.; Martin, D.

    2015-12-01

    Prior geologic studies of the San Diego area, including northern Baja California, Mexico, focused on site investigations, characterization of rock formations, or earthquake hazards. No comprehensive, quantitative model characterizing the three-dimensional (3D) geology of the entire area has been developed. The lack of such a model limits understanding of large-scale processes, such as development of ancient landforms, and groundwater movement and availability. To evaluate these regional processes, the United States Geological Survey (USGS) conducted a study to better understand the geologic structure of the San Diego area. A cornerstone of this study is the installation and analysis of 77 wells at 12 multiple-depth monitoring-well sites. Geologic information from these wells was combined with lithologic data from 81 oil exploration wells and municipal and private water wells, gravity and seismic interpretations, and paleontological interpretations. These data were analyzed in conjunction with geologic maps and digital elevation models to develop a 3D geologic model of the San Diego area, in particular of the San Diego embayment. Existing interpretations of regional surficial geology, faulting, and tectonic history provided the framework for this model, which was refined by independent evaluation of subsurface geology. Geologic formations were simplified into five sedimentary units (Quaternary, Plio-Pleistocene, Oligocene, Eocene and Cretaceous ages), and one basal crystalline unit (primarily Cretaceous and Jurassic). Complex fault systems are represented in the model by ten fault strands that maintain overall displacement. The 3D geologic model corroborates existing geologic concepts of the San Diego area, refines the extent of subsurface geology, and allows users to holistically evaluate subsurface structures and regional hydrogeology.

  13. Modeling and Processing of Continuous 3D Elastic Wavefield Data

    NASA Astrophysics Data System (ADS)

    Milkereit, B.; Bohlen, T.

    2001-12-01

    Continuous seismic wavefields are excited by earthquake clustering, induced seismicity in reservoirs, and mining. In hydrocarbon reservoirs, for example, pore pressure changes and fluid flow (mass transfer) will cause incremental deviatoric stresses sufficient to trigger and sustain seismic activity. Here we address three aspects of seismic wavefields in three-dimensional heterogeneous media triggered by distributed sources in space and time: forward modeling, multichannel data processing, and source location imaging. A power law distribution of seismic sources (such as the Gutenberg-Richter law) is used for the modeling of viscoelastic/elastic wave propagation through a realistic earth model. 3D modeling provides new insight in the interaction of multi-source wavefields and the role of scale-dependend elastic model parameters on transmitted and reflected/back-scattered wavefields. There exists a strong correlation between the spatial properties of the compressional, shear wave and density perturbations and the lateral correlation length of the resulting reflected or transmitted seismic wavefields. Modeling is based on the implementation of 3D elastic/viscoelastic FD codes on massive parallel and/or distributed computing resources using MPI (message passing interface). For parallelization, large grid 3D earth models are decomposed into subvolume processing elements whereby each processing element is updating the wavefield within its portion of the grid. Processing of continuous seismic wavefields excited by multiple distributed sources is based on a combination of crosscorrelated or slowness-transformed array data and Kirchhoff or reverse time migration for source location or source volume imaging. The appearance of slowness in both migration and array data processing suggests the possibility of combining them into a single process. In order to place further constraints on the migration, the directivity properties of 3-component receiver arrays can be included in

  14. Underwater 3d Modeling: Image Enhancement and Point Cloud Filtering

    NASA Astrophysics Data System (ADS)

    Sarakinou, I.; Papadimitriou, K.; Georgoula, O.; Patias, P.

    2016-06-01

    This paper examines the results of image enhancement and point cloud filtering on the visual and geometric quality of 3D models for the representation of underwater features. Specifically it evaluates the combination of effects from the manual editing of images' radiometry (captured at shallow depths) and the selection of parameters for point cloud definition and mesh building (processed in 3D modeling software). Such datasets, are usually collected by divers, handled by scientists and used for geovisualization purposes. In the presented study, have been created 3D models from three sets of images (seafloor, part of a wreck and a small boat's wreck) captured at three different depths (3.5m, 10m and 14m respectively). Four models have been created from the first dataset (seafloor) in order to evaluate the results from the application of image enhancement techniques and point cloud filtering. The main process for this preliminary study included a) the definition of parameters for the point cloud filtering and the creation of a reference model, b) the radiometric editing of images, followed by the creation of three improved models and c) the assessment of results by comparing the visual and the geometric quality of improved models versus the reference one. Finally, the selected technique is tested on two other data sets in order to examine its appropriateness for different depths (at 10m and 14m) and different objects (part of a wreck and a small boat's wreck) in the context of an ongoing research in the Laboratory of Photogrammetry and Remote Sensing.

  15. Subduction zone guided waves: 3D modelling and attenuation effects

    NASA Astrophysics Data System (ADS)

    Garth, T.; Rietbrock, A.

    2013-12-01

    Waveform modelling is an important tool for understanding complex seismic structures such as subduction zone waveguides. These structures are often simplified to 2D structures for modelling purposes to reduce computational costs. In the case of subduction zone waveguide affects, 2D models have shown that dispersed arrivals are caused by a low velocity waveguide, inferred to be subducted oceanic crust and/or hydrated outer rise normal faults. However, due to the 2D modelling limitations the inferred seismic properties such as velocity contrast and waveguide thickness are still debated. Here we test these limitations with full 3D waveform modelling. For waveguide effects to be observable the waveform must be accurately modelled to relatively high frequencies (> 2 Hz). This requires a small grid spacing due to the high seismic velocities present in subduction zones. A large area must be modelled as well due to the long propagation distances (400 - 600 km) of waves interacting with subduction zone waveguides. The combination of the large model area and small grid spacing required means that these simulations require a large amount of computational resources, only available at high performance computational centres like the UK National super computer HECTOR (used in this study). To minimize the cost of modelling for such a large area, the width of the model area perpendicular to the subduction trench (the y-direction) is made as small as possible. This reduces the overall volume of the 3D model domain. Therefore the wave field is simulated in a model ';corridor' of the subduction zone velocity structure. This introduces new potential sources of error particularly from grazing wave side reflections in the y-direction. Various dampening methods are explored to reduce these grazing side reflections, including perfectly matched layers (PML) and more traditional exponential dampening layers. Defining a corridor model allows waveguide affects to be modelled up to at least 2

  16. 3D flare particle model for ShipIR/NTCS

    NASA Astrophysics Data System (ADS)

    Ramaswamy, Srinivasan; Vaitekunas, David A.

    2016-05-01

    A key component in any soft-kill response to an incoming guided missile is the flare /chaff decoy used to distract or seduce the seeker homing system away from the naval platform. This paper describes a new 3D flare particle model in the naval threat countermeasure simulator (NTCS) of the NATO-standard ship signature model (ShipIR), which provides independent control over the size and radial distribution of its signature. The 3D particles of each flare sub-munition are modelled stochastically and rendered using OpenGL z-buffering, 2D projection, and alpha-blending to produce a unique and time varying signature. A sensitivity analysis on each input parameter provides the data and methods needed to synthesize a model from an IR measurement of a decoy. The new model also eliminated artifacts and deficiencies in our previous model which prevented reliable tracks from the adaptive track gate algorithm already presented by Ramaswamy and Vaitekunas (2015). A sequence of scenarios are used to test and demonstrate the new flare model during a missile engagement.

  17. 3D finite element model for treatment of cleft lip

    NASA Astrophysics Data System (ADS)

    Jiao, Chun; Hong, Dongming; Lu, Hongbing; Wang, Jianqi; Lin, Qin; Liang, Zhengrong

    2009-02-01

    Cleft lip is a congenital facial deformity with high occurrence rate in China. Surgical procedure involving Millard or Tennison methods is usually employed for treatment of cleft lip. However, due to the elasticity of the soft tissues and the mechanical interaction between skin and maxillary, the occurrence rate of facial abnormality or dehisce is still high after the surgery, leading to multiple operations of the patient. In this study, a framework of constructing a realistic 3D finite element model (FEM) for the treatment of cleft lip has been established. It consists of two major steps. The first one is the reconstruction of a 3D geometrical model of the cleft lip from scanning CT data. The second step is the build-up of a FEM for cleft lip using the geometric model, where the material property of all the tetrahedrons was calculated from the CT densities directly using an empirical curve. The simulation results demonstrated (1) the deformation procedure of the model step-by-step when forces were applied, (2) the stress distribution inside the model, and (3) the displacement of all elements in the model. With the computer simulation, the minimal force of having the cleft be repaired is predicted, as well as whether a given force sufficient for the treatment of a specific individual. It indicates that the proposed framework could integrate the treatment planning with stress analysis based on a realistic patient model.

  18. 3D statistical shape models incorporating 3D random forest regression voting for robust CT liver segmentation

    NASA Astrophysics Data System (ADS)

    Norajitra, Tobias; Meinzer, Hans-Peter; Maier-Hein, Klaus H.

    2015-03-01

    During image segmentation, 3D Statistical Shape Models (SSM) usually conduct a limited search for target landmarks within one-dimensional search profiles perpendicular to the model surface. In addition, landmark appearance is modeled only locally based on linear profiles and weak learners, altogether leading to segmentation errors from landmark ambiguities and limited search coverage. We present a new method for 3D SSM segmentation based on 3D Random Forest Regression Voting. For each surface landmark, a Random Regression Forest is trained that learns a 3D spatial displacement function between the according reference landmark and a set of surrounding sample points, based on an infinite set of non-local randomized 3D Haar-like features. Landmark search is then conducted omni-directionally within 3D search spaces, where voxelwise forest predictions on landmark position contribute to a common voting map which reflects the overall position estimate. Segmentation experiments were conducted on a set of 45 CT volumes of the human liver, of which 40 images were randomly chosen for training and 5 for testing. Without parameter optimization, using a simple candidate selection and a single resolution approach, excellent results were achieved, while faster convergence and better concavity segmentation were observed, altogether underlining the potential of our approach in terms of increased robustness from distinct landmark detection and from better search coverage.

  19. Bazhenov fm unconventional reservoir 3D geological modeling methodology

    NASA Astrophysics Data System (ADS)

    Telnova, A.; Baranov, V.; Bukhanov, N.

    2016-03-01

    The Bazhenov Formation has been studied for more than 50 years, but its petroleum potential, optimal STOIIP or resource estimation approaches, the methodology used to select a reservoir, determine its properties are still unclear. The distinctive features of bituminous shale are specific geochemical properties chosen as basic parameters to perform the geological modeling of the Bazhenov deposits and determine the key areas. The main objective of this paper is to choose an optimal 3D geological modeling algorithm and test conventional (petrophysical) and specific (geochemical) properties.

  20. Towards Forward Modeling of 3D Heterogeneity in D" region

    NASA Astrophysics Data System (ADS)

    To, A.; Capdeville, Y.; Romanowicz, B.

    2002-12-01

    The presence of strong lateral heterogeneity in D" is now well documented. While tomographic modeling provides constraints on the large scale patterns, strong variations on shorter scales are best addressed by forward modeling. Appropriate tools are needed for forward modeling that will handle strong 3D heterogeneity, at relatively short periods and including diffracted waves. We use a coupled mode/SEM (Spectral Element Method) to compute synthetic seismograms in 3D models of the D" layer down to 1/12s. This coupled method (Capdeville, 2001) affords faster computations than SEM in cases where heterogeneity can be restricted to a specific layer. We compare them with observed waveforms for several events in the Western Pacific. Observed and synthetic travel time trends are very consistent, although in most cases the observed residuals are significantly larger. Waveform amplitudes are less consistent. In order to understand the origin of the amplitude difference, we test the effect of 3D heterogeneity on Sdiff phase. In particular, the results show opposite trends in the amplitude of Sdiff due to heterogeneity located near the CMB or well above it. This provides constraints on the location of the causative velocity heterogeneity. Because the forward modeling approach requires many iterations, the coupled mode/SEM approach is still computationally intensive. It is more efficient to use a less accurate traditional approach to first get closer to a final model, and only then use coupled mode/SEM to refine the model. Ray theory is the most expedient way to calculate travel times. However, it is an infinite frequency approximation and not appropriate to handle diffracting waves. We show that ray theory predicts larger travel time anomaly for Sdiff phase than the one obtained by coupled mode/SEM. Although it is based on a weak heterogeneity assumption, Non-linear Asymptotic Coupling Theory(NACT) (Li and Romanowicz, 1995) helps to overcome this difficulty. It can handle

  1. 3D Virtual Reality Applied in Tectonic Geomorphic Study of the Gombori Range of Greater Caucasus Mountains

    NASA Astrophysics Data System (ADS)

    Sukhishvili, Lasha; Javakhishvili, Zurab

    2016-04-01

    Gombori Range represents the southern part of the young Greater Caucasus Mountains and stretches from NW to SE. The range separates Alazani and Iori basins within the eastern Georgian province of Kakheti. The active phase of Caucasian orogeny started in the Pliocene, but according to alluvial sediments of Gombori range (mapped in the Soviet geologic map), we observe its uplift process to be Quaternary event. The highest peak of the Gombori range has an absolute elevation of 1991 m, while its neighboring Alazani valley gains only 400 m. We assume the range has a very fast uplift rate and it could trigger streams flow direction course reverse in Quaternary. To check this preliminary assumptions we are going to use a tectonic and fluvial geomorphic and stratigraphic approaches including paleocurrent analyses and various affordable absolute dating techniques to detect the evidence of river course reverses and date them. For these purposes we have selected river Turdo outcrop. The river itself flows northwards from the Gombori range and nearby region`s main city of Telavi generates 30-40 m high continuous outcrop along 1 km section. Turdo outcrop has very steep walls and requires special climbing skills to work on it. The goal of this particularly study is to avoid time and resource consuming ground survey process of this steep, high and wide outcrop and test 3D aerial and ground base photogrammetric modelling and analyzing approaches in initial stage of the tectonic geomorphic study. Using this type of remote sensing and virtual lab analyses of 3D outcrop model, we roughly delineated stratigraphic layers, selected exact locations for applying various research techniques and planned safe and suitable climbing routes for getting to the investigation sites.

  2. Digital 3D Borobudur - Integration of 3D surveying and modeling techniques

    NASA Astrophysics Data System (ADS)

    Suwardhi, D.; Menna, F.; Remondino, F.; Hanke, K.; Akmalia, R.

    2015-08-01

    The Borobudur temple (Indonesia) is one of the greatest Buddhist monuments in the world, now listed as an UNESCO World Heritage Site. The present state of the temple is the result of restorations after being exposed to natural disasters several times. Today there is still a growing rate of deterioration of the building stones whose causes need further researches. Monitoring programs, supported at institutional level, have been effectively executed to observe the problem. The paper presents the latest efforts to digitally document the Borobudur Temple and its surrounding area in 3D with photogrammetric techniques. UAV and terrestrial images were acquired to completely digitize the temple, produce DEM, orthoimages and maps at 1:100 and 1:1000 scale. The results of the project are now employed by the local government organizations to manage the heritage area and plan new policies for the conservation and preservation of the UNESCO site. In order to help data management and policy makers, a web-based information system of the heritage area was also built to visualize and easily access all the data and achieved 3D results.

  3. Discrete Method of Images for 3D Radio Propagation Modeling

    NASA Astrophysics Data System (ADS)

    Novak, Roman

    2016-09-01

    Discretization by rasterization is introduced into the method of images (MI) in the context of 3D deterministic radio propagation modeling as a way to exploit spatial coherence of electromagnetic propagation for fine-grained parallelism. Traditional algebraic treatment of bounding regions and surfaces is replaced by computer graphics rendering of 3D reflections and double refractions while building the image tree. The visibility of reception points and surfaces is also resolved by shader programs. The proposed rasterization is shown to be of comparable run time to that of the fundamentally parallel shooting and bouncing rays. The rasterization does not affect the signal evaluation backtracking step, thus preserving its advantage over the brute force ray-tracing methods in terms of accuracy. Moreover, the rendering resolution may be scaled back for a given level of scenario detail with only marginal impact on the image tree size. This allows selection of scene optimized execution parameters for faster execution, giving the method a competitive edge. The proposed variant of MI can be run on any GPU that supports real-time 3D graphics.

  4. A Shell/3D Modeling Technique for Delaminations in Composite Laminates

    NASA Technical Reports Server (NTRS)

    Krueger, Ronald

    1999-01-01

    A shell/3D modeling technique was developed for which a local solid finite element model is used only in the immediate vicinity of the delamination front. The goal was to combine the accuracy of the full three-dimensional solution with the computational efficiency of a plate or shell finite element model. Multi-point constraints provide a kinematically compatible interface between the local 3D model and the global structural model which has been meshed with plate or shell finite elements. For simple double cantilever beam (DCB), end notched flexure (ENF), and single leg bending (SLB) specimens, mixed mode energy release rate distributions were computed across the width from nonlinear finite element analyses using the virtual crack closure technique. The analyses served to test the accuracy of the shell/3D technique for the pure mode I case (DCB), mode II case (ENF) and a mixed mode I/II case (SLB). Specimens with a unidirectional layup where the delamination is located between two 0 plies, as well as a multidirectional layup where the delamination is located between two non-zero degree plies, were simulated. For a local 3D model extending to a minimum of about three specimen thicknesses in front of and behind the delamination front, the results were in good agreement with mixed mode strain energy release rates obtained from computations where the entire specimen had been modeled with solid elements. For large built-up composite structures modeled with plate elements, the shell/3D modeling technique offers a great potential, since only a relatively small section in the vicinity of the delamination front needs to be modeled with solid elements.

  5. 3D Building Evacuation Route Modelling and Visualization

    NASA Astrophysics Data System (ADS)

    Chan, W.; Armenakis, C.

    2014-11-01

    The most common building evacuation approach currently applied is to have evacuation routes planned prior to these emergency events. These routes are usually the shortest and most practical path from each building room to the closest exit. The problem with this approach is that it is not adaptive. It is not responsively configurable relative to the type, intensity, or location of the emergency risk. Moreover, it does not provide any information to the affected persons or to the emergency responders while not allowing for the review of simulated hazard scenarios and alternative evacuation routes. In this paper we address two main tasks. The first is the modelling of the spatial risk caused by a hazardous event leading to choosing the optimal evacuation route for a set of options. The second is to generate a 3D visual representation of the model output. A multicriteria decision making (MCDM) approach is used to model the risk aiming at finding the optimal evacuation route. This is achieved by using the analytical hierarchy process (AHP) on the criteria describing the different alternative evacuation routes. The best route is then chosen to be the alternative with the least cost. The 3D visual representation of the model displays the building, the surrounding environment, the evacuee's location, the hazard location, the risk areas and the optimal evacuation pathway to the target safety location. The work has been performed using ESRI's ArcGIS. Using the developed models, the user can input the location of the hazard and the location of the evacuee. The system then determines the optimum evacuation route and displays it in 3D.

  6. Image-Based Airborne LiDAR Point Cloud Encoding for 3d Building Model Retrieval

    NASA Astrophysics Data System (ADS)

    Chen, Yi-Chen; Lin, Chao-Hung

    2016-06-01

    With the development of Web 2.0 and cyber city modeling, an increasing number of 3D models have been available on web-based model-sharing platforms with many applications such as navigation, urban planning, and virtual reality. Based on the concept of data reuse, a 3D model retrieval system is proposed to retrieve building models similar to a user-specified query. The basic idea behind this system is to reuse these existing 3D building models instead of reconstruction from point clouds. To efficiently retrieve models, the models in databases are compactly encoded by using a shape descriptor generally. However, most of the geometric descriptors in related works are applied to polygonal models. In this study, the input query of the model retrieval system is a point cloud acquired by Light Detection and Ranging (LiDAR) systems because of the efficient scene scanning and spatial information collection. Using Point clouds with sparse, noisy, and incomplete sampling as input queries is more difficult than that by using 3D models. Because that the building roof is more informative than other parts in the airborne LiDAR point cloud, an image-based approach is proposed to encode both point clouds from input queries and 3D models in databases. The main goal of data encoding is that the models in the database and input point clouds can be consistently encoded. Firstly, top-view depth images of buildings are generated to represent the geometry surface of a building roof. Secondly, geometric features are extracted from depth images based on height, edge and plane of building. Finally, descriptors can be extracted by spatial histograms and used in 3D model retrieval system. For data retrieval, the models are retrieved by matching the encoding coefficients of point clouds and building models. In experiments, a database including about 900,000 3D models collected from the Internet is used for evaluation of data retrieval. The results of the proposed method show a clear superiority

  7. Modeling the GFR with RELAP5-3D

    SciTech Connect

    Cliff B. Davis; Theron D. Marshall; K. D. Weaver

    2005-09-01

    Significant improvements have been made to the RELAP5-3D computer code for analysis of the Gas Fast Reactor (GFR). These improvements consisted of adding carbon dioxide as a working fluid, improving the turbine component, developing a compressor model, and adding the Gnielinski heat transfer correlation. The code improvements were validated, generally through comparisons with independent design calculations. A model of the power conversion unit of the GFR was developed. The model of the power conversion unit was coupled to a reactor model to develop a complete model of the GFR system. The RELAP5 model of the GFR was used to simulate two transients, one initiated by a reactor trip and the other initiated by a loss of load.

  8. Testing Mercury Porosimetry with 3D Printed Porosity Models

    NASA Astrophysics Data System (ADS)

    Hasiuk, F.; Ewing, R. P.; Hu, Q.

    2014-12-01

    Mercury intrusion porosimetry is one of the most widely used techniques to study the porous nature of a geological and man-made materials. In the geosciences, it is commonly used to describe petroleum reservoir and seal rocks as well as to grade aggregates for the design of asphalt and portland cement concretes. It's wide utility stems from its ability to characterize a wide range of pore throat sizes (from nanometers to around a millimeter). The fundamental physical model underlying mercury intrusion porosimetry, the Washburn Equation, is based on the assumption that rock porosity can be described as a bundle of cylindrical tubes. 3D printing technology, also known as rapid prototyping, allows the construction of intricate and accurate models, exactly what is required to build models of rock porosity. We evaluate the applicability of the Washburn Equation by comparing properties (like porosity, pore and pore throat size distribution, and surface area) computed on digital porosity models (built from CT data, CAD designs, or periodic geometries) to properties measured via mercury intrusion porosimetry on 3D printed versions of the same digital porosity models.

  9. 3D model tools for architecture and archaeology reconstruction

    NASA Astrophysics Data System (ADS)

    Vlad, Ioan; Herban, Ioan Sorin; Stoian, Mircea; Vilceanu, Clara-Beatrice

    2016-06-01

    The main objective of architectural and patrimonial survey is to provide a precise documentation of the status quo of the surveyed objects (monuments, buildings, archaeological object and sites) for preservation and protection, for scientific studies and restoration purposes, for the presentation to the general public. Cultural heritage documentation includes an interdisciplinary approach having as purpose an overall understanding of the object itself and an integration of the information which characterize it. The accuracy and the precision of the model are directly influenced by the quality of the measurements realized on field and by the quality of the software. The software is in the process of continuous development, which brings many improvements. On the other side, compared to aerial photogrammetry, close range photogrammetry and particularly architectural photogrammetry is not limited to vertical photographs with special cameras. The methodology of terrestrial photogrammetry has changed significantly and various photographic acquisitions are widely in use. In this context, the present paper brings forward a comparative study of TLS (Terrestrial Laser Scanner) and digital photogrammetry for 3D modeling. The authors take into account the accuracy of the 3D models obtained, the overall costs involved for each technology and method and the 4th dimension - time. The paper proves its applicability as photogrammetric technologies are nowadays used at a large scale for obtaining the 3D model of cultural heritage objects, efficacious in their assessment and monitoring, thus contributing to historic conservation. Its importance also lies in highlighting the advantages and disadvantages of each method used - very important issue for both the industrial and scientific segment when facing decisions such as in which technology to invest more research and funds.

  10. 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.

  11. Recent progress in modelling 3D lithospheric deformation

    NASA Astrophysics Data System (ADS)

    Kaus, B. J. P.; Popov, A.; May, D. A.

    2012-04-01

    Modelling 3D lithospheric deformation remains a challenging task, predominantly because the variations in rock types, as well as nonlinearities due to for example plastic deformation result in sharp and very large jumps in effective viscosity contrast. As a result, there are only a limited number of 3D codes available, most of which are using direct solvers which are computationally and memory-wise very demanding. As a result, the resolutions for typical model runs are quite modest, despite the use of hundreds of processors (and using much larger computers is unlikely to bring much improvement in this situation). For this reason we recently developed a new 3D deformation code,called LaMEM: Lithosphere and Mantle Evolution Model. LaMEM is written on top of PETSc, and as a result it runs on massive parallel machines and we have a large number of iterative solvers available (including geometric and algebraic multigrid methods). As it remains unclear which solver combinations work best under which conditions, we have implemented most currently suggested methods (such as schur complement reduction or Fully coupled iterations). In addition, we can use either a finite element discretization (with Q1P0, stabilized Q1Q1 or Q2P-1 elements) or a staggered finite difference discretization for the same input geometry, which is based on a marker and cell technique). This gives us he flexibility to test various solver methodologies on the same model setup, in terms of accuracy, speed, memory usage etc. Here, we will report on some features of LaMEM, on recent code additions, as well as on some lessons we learned which are important for modelling 3D lithospheric deformation. Specifically we will discuss: 1) How we combine a particle-and-cell method to make it work with both a finite difference and a (lagrangian, eulerian or ALE) finite element formulation, with only minor code modifications code 2) How finite difference and finite element discretizations compare in terms of

  12. 3-D Modeling of a Nearshore Dye Release

    NASA Astrophysics Data System (ADS)

    Maxwell, A. R.; Hibler, L. F.; Miller, L. M.

    2006-12-01

    The usage of computer modeling software in predicting the behavior of a plume discharged into deep water is well established. Nearfield plume spreading in coastal areas with complex bathymetry is less commonly studied; in addition to geometry, some of the difficulties of this environment include: tidal exchange, temperature, and salinity gradients. Although some researchers have applied complex hydrodynamic models to this problem, nearfield regions are typically modeled by calibration of an empirical or expert system model. In the present study, the 3D hydrodynamic model Delft3D-FLOW was used to predict the advective transport from a point release in Sequim Bay, Washington. A nested model approach was used, wherein a coarse model using a mesh extending to nearby tide gages (cell sizes up to 1 km) was run over several tidal cycles in order to provide boundary conditions to a smaller area. The nested mesh (cell sizes up to 30 m) was forced on two open boundaries using the water surface elevation derived from the coarse model. Initial experiments with the uncalibrated model were conducted in order to predict plume propagation based on the best available field data. Field experiments were subsequently carried out by releasing rhodamine dye into the bay at near-peak flood tidal current and near high slack tidal conditions. Surface and submerged releases were carried out from an anchored vessel. Concurrently collected data from the experiment include temperature, salinity, dye concentration, and hyperspectral imagery, collected from boats and aircraft. A REMUS autonomous underwater vehicle was used to measure current velocity and dye concentration at varying depths, as well as to acquire additional bathymetric information. Preliminary results indicate that the 3D hydrodynamic model offers a reasonable prediction of plume propagation speed and shape. A sensitivity analysis is underway to determine the significant factors in effectively using the model as a predictive tool

  13. Discussion of Source Reconstruction Models Using 3D MCG Data

    NASA Astrophysics Data System (ADS)

    Melis, Massimo De; Uchikawa, Yoshinori

    In this study we performed the source reconstruction of magnetocardiographic signals generated by the human heart activity to localize the site of origin of the heart activation. The localizations were performed in a four compartment model of the human volume conductor. The analyses were conducted on normal subjects and on a subject affected by the Wolff-Parkinson-White syndrome. Different models of the source activation were used to evaluate whether a general model of the current source can be applied in the study of the cardiac inverse problem. The data analyses were repeated using normal and vector component data of the MCG. The results show that a distributed source model has the better accuracy in performing the source reconstructions, and that 3D MCG data allow finding smaller differences between the different source models.

  14. Modeling moving systems with RELAP5-3D

    DOE PAGESBeta

    Mesina, G. L.; Aumiller, David L.; Buschman, Francis X.; Kyle, Matt R.

    2015-12-04

    RELAP5-3D is typically used to model stationary, land-based reactors. However, it can also model reactors in other inertial and accelerating frames of reference. By changing the magnitude of the gravitational vector through user input, RELAP5-3D can model reactors on a space station or the moon. The field equations have also been modified to model reactors in a non-inertial frame, such as occur in land-based reactors during earthquakes or onboard spacecraft. Transient body forces affect fluid flow in thermal-fluid machinery aboard accelerating crafts during rotational and translational accelerations. It is useful to express the equations of fluid motion in the acceleratingmore » frame of reference attached to the moving craft. However, careful treatment of the rotational and translational kinematics is required to accurately capture the physics of the fluid motion. Correlations for flow at angles between horizontal and vertical are generated via interpolation where no experimental studies or data exist. The equations for three-dimensional fluid motion in a non-inertial frame of reference are developed. As a result, two different systems for describing rotational motion are presented, user input is discussed, and an example is given.« less

  15. Modeling moving systems with RELAP5-3D

    SciTech Connect

    Mesina, G. L.; Aumiller, David L.; Buschman, Francis X.; Kyle, Matt R.

    2015-12-04

    RELAP5-3D is typically used to model stationary, land-based reactors. However, it can also model reactors in other inertial and accelerating frames of reference. By changing the magnitude of the gravitational vector through user input, RELAP5-3D can model reactors on a space station or the moon. The field equations have also been modified to model reactors in a non-inertial frame, such as occur in land-based reactors during earthquakes or onboard spacecraft. Transient body forces affect fluid flow in thermal-fluid machinery aboard accelerating crafts during rotational and translational accelerations. It is useful to express the equations of fluid motion in the accelerating frame of reference attached to the moving craft. However, careful treatment of the rotational and translational kinematics is required to accurately capture the physics of the fluid motion. Correlations for flow at angles between horizontal and vertical are generated via interpolation where no experimental studies or data exist. The equations for three-dimensional fluid motion in a non-inertial frame of reference are developed. As a result, two different systems for describing rotational motion are presented, user input is discussed, and an example is given.

  16. 3D interactive model of lumbar spinal structures of anesthetic interest.

    PubMed

    Prats-Galino, Alberto; Reina, Miguel A; Mavar Haramija, Marija; Puigdellivol-Sánchez, Anna; Juanes Méndez, Juan A; De Andrés, José A

    2015-03-01

    A 3D model of lumbar structures of anesthetic interest was reconstructed from human magnetic resonance (MR) images and embedded in a Portable Document Format (PDF) file, which can be opened by freely available software and used offline. The MR images were analyzed using a specific 3D software platform for biomedical data. Models generated from manually delimited volumes of interest and selected MR images were exported to Virtual Reality Modeling Language format and were presented in a PDF document containing JavaScript-based functions. The 3D file and the corresponding instructions and license files can be downloaded freely at http://diposit.ub.edu/dspace/handle/2445/44844?locale=en. The 3D PDF interactive file includes reconstructions of the L3-L5 vertebrae, intervertebral disks, ligaments, epidural and foraminal fat, dural sac and nerve root cuffs, sensory and motor nerve roots of the cauda equina, and anesthetic approaches (epidural medial, spinal paramedial, and selective nerve root paths); it also includes a predefined sequential educational presentation. Zoom, 360° rotation, selective visualization, and transparency graduation of each structure and clipping functions are available. Familiarization requires no specialized informatics knowledge. The ease with which the document can be used could make it valuable for anatomical and anesthetic teaching and demonstration of patient information. PMID:25352014

  17. Reassessing Geophysical Models of the Bushveld Complex in 3D

    NASA Astrophysics Data System (ADS)

    Cole, J.; Webb, S. J.; Finn, C.

    2012-12-01

    Conceptual geophysical models of the Bushveld Igneous Complex show three possible geometries for its mafic component: 1) Separate intrusions with vertical feeders for the eastern and western lobes (Cousins, 1959) 2) Separate dipping sheets for the two lobes (Du Plessis and Kleywegt, 1987) 3) A single saucer-shaped unit connected at depth in the central part between the two lobes (Cawthorn et al, 1998) Model three incorporates isostatic adjustment of the crust in response to the weight of the dense mafic material. The model was corroborated by results of a broadband seismic array over southern Africa, known as the Southern African Seismic Experiment (SASE) (Nguuri, et al, 2001; Webb et al, 2004). This new information about the crustal thickness only became available in the last decade and could not be considered in the earlier models. Nevertheless, there is still on-going debate as to which model is correct. All of the models published up to now have been done in 2 or 2.5 dimensions. This is not well suited to modelling the complex geometry of the Bushveld intrusion. 3D modelling takes into account effects of variations in geometry and geophysical properties of lithologies in a full three dimensional sense and therefore affects the shape and amplitude of calculated fields. The main question is how the new knowledge of the increased crustal thickness, as well as the complexity of the Bushveld Complex, will impact on the gravity fields calculated for the existing conceptual models, when modelling in 3D. The three published geophysical models were remodelled using full 3Dl potential field modelling software, and including crustal thickness obtained from the SASE. The aim was not to construct very detailed models, but to test the existing conceptual models in an equally conceptual way. Firstly a specific 2D model was recreated in 3D, without crustal thickening, to establish the difference between 2D and 3D results. Then the thicker crust was added. Including the less

  18. 3D simulation of the Cluster-Cluster Aggregation model

    NASA Astrophysics Data System (ADS)

    Li, Chao; Xiong, Hailing

    2014-12-01

    We write a program to implement the Cluster-Cluster Aggregation (CCA) model with java programming language. By using the simulation program, the fractal aggregation growth process can be displayed dynamically in the form of a three-dimensional (3D) figure. Meanwhile, the related kinetics data of aggregation simulation can be also recorded dynamically. Compared to the traditional programs, the program has better real-time performance and is more helpful to observe the fractal growth process, which contributes to the scientific study in fractal aggregation. Besides, because of adopting java programming language, the program has very good cross-platform performance.

  19. A generic 3D kinetic model of gene expression

    NASA Astrophysics Data System (ADS)

    Zhdanov, Vladimir P.

    2012-04-01

    Recent experiments show that mRNAs and proteins can be localized both in prokaryotic and eukaryotic cells. To describe such situations, I present a 3D mean-field kinetic model aimed primarily at gene expression in prokaryotic cells, including the formation of mRNA, its translation into protein, and slow diffusion of these species. Under steady-state conditions, the mRNA and protein spatial distribution is described by simple exponential functions. The protein concentration near the gene transcribed into mRNA is shown to depend on the protein and mRNA diffusion coefficients and degradation rate constants.

  20. Unstructured 3D grid toolbox for modeling and simulation

    SciTech Connect

    George, D.

    1997-11-01

    Computable 3D grids that accurately represent complex multimaterial geometries are essential for both static and time-dependent modeling and simulation. LaGriT, the grid toolbox developed at Los Alamos provides a sophisticated set of initial grid generation, grid maintenance and grid optimization tools. We present example grids that demonstrate the flexibility of the grid generator. Additionally, we present the results of an electrostatic calculation and a grain growth problem that illustrate the grid optimization features and the utility of the grid server architecture.

  1. Software for Building Models of 3D Objects via the Internet

    NASA Technical Reports Server (NTRS)

    Schramer, Tim; Jensen, Jeff

    2003-01-01

    The Virtual EDF Builder (where EDF signifies Electronic Development Fixture) is a computer program that facilitates the use of the Internet for building and displaying digital models of three-dimensional (3D) objects that ordinarily comprise assemblies of solid models created previously by use of computer-aided-design (CAD) programs. The Virtual EDF Builder resides on a Unix-based server computer. It is used in conjunction with a commercially available Web-based plug-in viewer program that runs on a client computer. The Virtual EDF Builder acts as a translator between the viewer program and a database stored on the server. The translation function includes the provision of uniform resource locator (URL) links to other Web-based computer systems and databases. The Virtual EDF builder can be used in two ways: (1) If the client computer is Unix-based, then it can assemble a model locally; the computational load is transferred from the server to the client computer. (2) Alternatively, the server can be made to build the model, in which case the server bears the computational load and the results are downloaded to the client computer or workstation upon completion.

  2. Computerised 3-D anatomical modelling using plastinates: an example utilising the human heart.

    PubMed

    Tunali, S; Kawamoto, K; Farrell, M L; Labrash, S; Tamura, K; Lozanoff, S

    2011-08-01

    Computerised modelling methods have become highly useful for generating electronic representations of anatomical structures. These methods rely on crosssectional tissue slices in databases such as the Visible Human Male and Female, the Visible Korean Human, and the Visible Chinese Human. However, these databases are time consuming to generate and require labour-intensive manual digitisation while the number of specimens is very limited. Plastinated anatomical material could provide a possible alternative to data collection, requiring less time to prepare and enabling the use of virtually any anatomical or pathological structure routinely obtained in a gross anatomy laboratory. The purpose of this study was to establish an approach utilising plastinated anatomical material, specifically human hearts, for the purpose computerised 3-D modelling. Human hearts were collected following gross anatomical dissection and subjected to routine plastination procedures including dehydration (-25(o)C), defatting, forced impregnation, and curing at room temperature. A graphics pipeline was established comprising data collection with a hand-held scanner, 3-D modelling, model polishing, file conversion, and final rendering. Representative models were viewed and qualitatively assessed for accuracy and detail. The results showed that the heart model provided detailed surface information necessary for gross anatomical instructional purposes. Rendering tools facilitated optional model manipulation for further structural clarification if selected by the user. The use of plastinated material for generating 3-D computerised models has distinct advantages compared to cross-sectional tissue images. PMID:21866531

  3. A PC-based high-quality and interactive virtual endoscopy navigating system using 3D texture based volume rendering.

    PubMed

    Hwang, Jin-Woo; Lee, Jong-Min; Kim, In-Young; Song, In-Ho; Lee, Yong-Hee; Kim, SunI

    2003-05-01

    As an alternative method to optical endoscopy, visual quality and interactivity are crucial for virtual endoscopy. One solution is to use the 3D texture map based volume rendering method that offers high rendering speed without reducing visual quality. However, it is difficult to apply the method to virtual endoscopy. First, 3D texture mapping requires a high-end graphic workstation. Second, texture memory limits reduce the frame-rate. Third, lack of shading reduces visual quality significantly. As 3D texture mapping has become available on personal computers recently, we developed an interactive navigation system using 3D texture mapping on a personal computer. We divided the volume data into small cubes and tested whether the cubes had meaningful data. Only the cubes that passed the test were loaded into the texture memory and rendered. With the amount of data to be rendered minimized, rendering speed increased remarkably. We also improved visual quality by implementing full Phong shading based on the iso-surface shading method without sacrificing interactivity. With the developed navigation system, 256 x 256 x 256 sized brain MRA data was interactively explored with good image quality. PMID:12725966

  4. Simulation of 3D Global Wave Propagation Through Geodynamic Models

    NASA Astrophysics Data System (ADS)

    Schuberth, B.; Piazzoni, A.; Bunge, H.; Igel, H.; Steinle-Neumann, G.

    2005-12-01

    This project aims at a better understanding of the forward problem of global 3D wave propagation. We use the spectral element program "SPECFEM3D" (Komatitsch and Tromp, 2002a,b) with varying input models of seismic velocities derived from mantle convection simulations (Bunge et al., 2002). The purpose of this approach is to obtain seismic velocity models independently from seismological studies. In this way one can test the effects of varying parameters of the mantle convection models on the seismic wave field. In order to obtain the seismic velocities from the temperature field of the geodynamical simulations we follow a mineral physics approach. Assuming a certain mantle composition (e.g. pyrolite with CMASF composition) we compute the stable phases for each depth (i.e. pressure) and temperature by system Gibbs free energy minimization. Elastic moduli and density are calculated from the equations of state of the stable mineral phases. For this we use a mineral physics database derived from calorimetric experiments (enthalphy and entropy of formation, heat capacity) and EOS parameters.

  5. L2 Immersion in 3D Virtual Worlds: The Next Thing to Being There?

    ERIC Educational Resources Information Center

    Paillat, Edith

    2014-01-01

    Second Life is one of the many three-dimensional virtual environments accessible through a computer and a fast broadband connection. Thousands of participants connect to this platform to interact virtually with the world, join international communities of practice and, for some, role play groups. Unlike online role play games however, Second Life…

  6. 3D Model of Melt Distribution in Partially Molten Dunite

    NASA Astrophysics Data System (ADS)

    Garapic, G.; Faul, U.; Brisson, E.

    2010-12-01

    The currently existing model of grain-scale melt geometry in the Earth’s upper mantle is derived from theoretical considerations that stem from material science research, combined with relatively low-resolution observations of polished two-dimensional surfaces. This model predicts a simple, interconnected network of melt along three-grain edges in static surface energy equilibrium. However, due to a continuous rearrangements of neighboring grains caused by grain growth, melt forms complex shapes among the grains. As a result, it is impossible to construct a 3D image of the pore space from 2D surfaces, which makes it particularly challenging to resolve the current controversy on whether all two-grain boundaries are wetted or melt-free. We present a new method for reconstruction of the 3D pore space in partially molten rocks. The method consists of serial sectioning and high resolution imaging (Field Emission SEM) of polished surfaces, followed by image alignment and rendering. The ablation rate during serial sectioning is determined by measuring the depth of a laser hole by interferometry. We removed a total of 25 layers with a spacing of of 1.3.microns between layers. Each layer consists of a mosaic of images approximately 300 x 320 microns in size. Melt regions are identified within each layer by hand-digitizing SEM images. We obtain a 3D model by stacking the slices, registering each slice, and using alpha shapes as a surface reconstruction technique. The sample we investigated is a partially molten dunite consisting of Fo90 olivine with a mean grain size of 33 microns and 4% melt. It was run in a piston cylinder at 1350°C and 1 GPa for 432 hours to achieve steady state grain growth. Rendering of the 3D pore space shows that the larger melt pockets at multi-grain junctions change within only a few microns in depth, whereas thin inclusions along two-grain boundaries persist over the entire depth of the imaged volume, which is similar to the mean grain size

  7. On the Usability and Usefulness of 3d (geo)visualizations - a Focus on Virtual Reality Environments

    NASA Astrophysics Data System (ADS)

    Çöltekin, A.; Lokka, I.; Zahner, M.

    2016-06-01

    Whether and when should we show data in 3D is an on-going debate in communities conducting visualization research. A strong opposition exists in the information visualization (Infovis) community, and seemingly unnecessary/unwarranted use of 3D, e.g., in plots, bar or pie charts, is heavily criticized. The scientific visualization (Scivis) community, on the other hand, is more supportive of the use of 3D as it allows `seeing' invisible phenomena, or designing and printing things that are used in e.g., surgeries, educational settings etc. Geographic visualization (Geovis) stands between the Infovis and Scivis communities. In geographic information science, most visuo-spatial analyses have been sufficiently conducted in 2D or 2.5D, including analyses related to terrain and much of the urban phenomena. On the other hand, there has always been a strong interest in 3D, with similar motivations as in Scivis community. Among many types of 3D visualizations, a popular one that is exploited both for visual analysis and visualization is the highly realistic (geo)virtual environments. Such environments may be engaging and memorable for the viewers because they offer highly immersive experiences. However, it is not yet well-established if we should opt to show the data in 3D; and if yes, a) what type of 3D we should use, b) for what task types, and c) for whom. In this paper, we identify some of the central arguments for and against the use of 3D visualizations around these three considerations in a concise interdisciplinary literature review.

  8. A Prototype Digital Library for 3D Collections: Tools To Capture, Model, Analyze, and Query Complex 3D Data.

    ERIC Educational Resources Information Center

    Rowe, Jeremy; Razdan, Anshuman

    The Partnership for Research in Spatial Modeling (PRISM) project at Arizona State University (ASU) developed modeling and analytic tools to respond to the limitations of two-dimensional (2D) data representations perceived by affiliated discipline scientists, and to take advantage of the enhanced capabilities of three-dimensional (3D) data that…

  9. Canada in 3D - Toward a Sustainable 3D Model for Canadian Geology from Diverse Data Sources

    NASA Astrophysics Data System (ADS)

    Brodaric, B.; Pilkington, M.; Snyder, D. B.; St-Onge, M. R.; Russell, H.

    2015-12-01

    Many big science issues span large areas and require data from multiple heterogeneous sources, for example climate change, resource management, and hazard mitigation. Solutions to these issues can significantly benefit from access to a consistent and integrated geological model that would serve as a framework. However, such a model is absent for most large countries including Canada, due to the size of the landmass and the fragmentation of the source data into institutional and disciplinary silos. To overcome these barriers, the "Canada in 3D" (C3D) pilot project was recently launched by the Geological Survey of Canada. C3D is designed to be evergreen, multi-resolution, and inter-disciplinary: (a) it is to be updated regularly upon acquisition of new data; (b) portions vary in resolution and will initially consist of four layers (surficial, sedimentary, crystalline, and mantle) with intermediary patches of higher-resolution fill; and (c) a variety of independently managed data sources are providing inputs, such as geophysical, 3D and 2D geological models, drill logs, and others. Notably, scalability concerns dictate a decentralized and interoperable approach, such that only key control objects, denoting anchors for the modeling process, are imported into the C3D database while retaining provenance links to original sources. The resultant model is managed in the database, contains full modeling provenance as well as links to detailed information on rock units, and is to be visualized in desktop and online environments. It is anticipated that C3D will become the authoritative state of knowledge for the geology of Canada at a national scale.

  10. Comparative 3-D Modeling of tmRNA

    PubMed Central

    Burks, Jody; Zwieb, Christian; Müller, Florian; Wower, Iwona; Wower, Jacek

    2005-01-01

    Background Trans-translation releases stalled ribosomes from truncated mRNAs and tags defective proteins for proteolytic degradation using transfer-messenger RNA (tmRNA). This small stable RNA represents a hybrid of tRNA- and mRNA-like domains connected by a variable number of pseudoknots. Comparative sequence analysis of tmRNAs found in bacteria, plastids, and mitochondria provides considerable insights into their secondary structures. Progress toward understanding the molecular mechanism of template switching, which constitutes an essential step in trans-translation, is hampered by our limited knowledge about the three-dimensional folding of tmRNA. Results To facilitate experimental testing of the molecular intricacies of trans-translation, which often require appropriately modified tmRNA derivatives, we developed a procedure for building three-dimensional models of tmRNA. Using comparative sequence analysis, phylogenetically-supported 2-D structures were obtained to serve as input for the program ERNA-3D. Motifs containing loops and turns were extracted from the known structures of other RNAs and used to improve the tmRNA models. Biologically feasible 3-D models for the entire tmRNA molecule could be obtained. The models were characterized by a functionally significant close proximity between the tRNA-like domain and the resume codon. Potential conformational changes which might lead to a more open structure of tmRNA upon binding to the ribosome are discussed. The method, described in detail for the tmRNAs of Escherichia coli, Bacillus anthracis, and Caulobacter crescentus, is applicable to every tmRNA. Conclusion Improved molecular models of biological significance were obtained. These models will guide in the design of experiments and provide a better understanding of trans-translation. The comparative procedure described here for tmRNA is easily adopted for the modeling the members of other RNA families. PMID:15958166

  11. Dynamic deformable models for 3D MRI heart segmentation

    NASA Astrophysics Data System (ADS)

    Zhukov, Leonid; Bao, Zhaosheng; Gusikov, Igor; Wood, John; Breen, David E.

    2002-05-01

    Automated or semiautomated segmentation of medical images decreases interstudy variation, observer bias, and postprocessing time as well as providing clincally-relevant quantitative data. In this paper we present a new dynamic deformable modeling approach to 3D segmentation. It utilizes recently developed dynamic remeshing techniques and curvature estimation methods to produce high-quality meshes. The approach has been implemented in an interactive environment that allows a user to specify an initial model and identify key features in the data. These features act as hard constraints that the model must not pass through as it deforms. We have employed the method to perform semi-automatic segmentation of heart structures from cine MRI data.

  12. Stochastic Modeling of Calcium in 3D Geometry

    PubMed Central

    Mazel, Tomáš; Raymond, Rebecca; Raymond-Stintz, Mary; Jett, Stephen; Wilson, Bridget S.

    2009-01-01

    Release of inflammatory mediators by mast cells in type 1 immediate-hypersensitivity allergic reactions relies on antigen-dependent increases in cytosolic calcium. Here, we used a series of electron microscopy images to build a 3D reconstruction representing a slice through a rat tumor mast cell, which then served as a basis for stochastic modeling of inositol-trisphosphate-mediated calcium responses. The stochastic approach was verified by reaction-diffusion modeling within the same geometry. Local proximity of the endoplasmic reticulum to either the plasma membrane or mitochondria is predicted to differentially impact local inositol trisphosphate receptor transport. The explicit consideration of organelle spatial relationships represents an important step toward building a comprehensive, realistic model of cellular calcium dynamics. PMID:19254531

  13. Topological order in an exactly solvable 3D spin model

    SciTech Connect

    Bravyi, Sergey; Leemhuis, Bernhard; Terhal, Barbara M.

    2011-04-15

    Research highlights: RHtriangle We study exactly solvable spin model with six-qubit nearest neighbor interactions on a 3D face centered cubic lattice. RHtriangle The ground space of the model exhibits topological quantum order. RHtriangle Elementary excitations can be geometrically described as the corners of rectangular-shaped membranes. RHtriangle The ground space can encode 4g qubits where g is the greatest common divisor of the lattice dimensions. RHtriangle Logical operators acting on the encoded qubits are described in terms of closed strings and closed membranes. - Abstract: We study a 3D generalization of the toric code model introduced recently by Chamon. This is an exactly solvable spin model with six-qubit nearest-neighbor interactions on an FCC lattice whose ground space exhibits topological quantum order. The elementary excitations of this model which we call monopoles can be geometrically described as the corners of rectangular-shaped membranes. We prove that the creation of an isolated monopole separated from other monopoles by a distance R requires an operator acting on {Omega}(R{sup 2}) qubits. Composite particles that consist of two monopoles (dipoles) and four monopoles (quadrupoles) can be described as end-points of strings. The peculiar feature of the model is that dipole-type strings are rigid, that is, such strings must be aligned with face-diagonals of the lattice. For periodic boundary conditions the ground space can encode 4g qubits where g is the greatest common divisor of the lattice dimensions. We describe a complete set of logical operators acting on the encoded qubits in terms of closed strings and closed membranes.

  14. Creation of 3D multi-body orthodontic models by using independent imaging sensors.

    PubMed

    Barone, Sandro; Paoli, Alessandro; Razionale, Armando Viviano

    2013-01-01

    In the field of dental health care, plaster models combined with 2D radiographs are widely used in clinical practice for orthodontic diagnoses. However, complex malocclusions can be better analyzed by exploiting 3D digital dental models, which allow virtual simulations and treatment planning processes. In this paper, dental data captured by independent imaging sensors are fused to create multi-body orthodontic models composed of teeth, oral soft tissues and alveolar bone structures. The methodology is based on integrating Cone-Beam Computed Tomography (CBCT) and surface structured light scanning. The optical scanner is used to reconstruct tooth crowns and soft tissues (visible surfaces) through the digitalization of both patients' mouth impressions and plaster casts. These data are also used to guide the segmentation of internal dental tissues by processing CBCT data sets. The 3D individual dental tissues obtained by the optical scanner and the CBCT sensor are fused within multi-body orthodontic models without human supervisions to identify target anatomical structures. The final multi-body models represent valuable virtual platforms to clinical diagnostic and treatment planning. PMID:23385416

  15. Analysis for Clinical Effect of Virtual Windowing and Poking Reduction Treatment for Schatzker III Tibial Plateau Fracture Based on 3D CT Data

    PubMed Central

    Zhang, Huafeng; Li, Zhijun; Xu, Qian; Zhang, Yuan; Xu, Ke; Ma, Xinlong

    2015-01-01

    Objective. To explore the applications of preoperative planning and virtual surgery including surgical windowing and elevating reduction and to determine the clinical effects of this technology on the treatment of Schatzker type III tibial plateau fractures. Methods. 32 patients with Schatzker type III tibial plateau fractures were randomised upon their admission to the hospital using a sealed envelope method. Fourteen were treated with preoperative virtual design and assisted operation (virtual group) and 18 with direct open reduction and internal fixation (control group). Results. All patients achieved primary incision healing. Compared with control group, virtual groups showed significant advantages in operative time, incision length, and blood loss (P < 0.001). The virtual surgery was consistent with the actual surgery. Conclusion. The virtual group was better than control group in the treatment of tibial plateau fractures of Schatzker type III, due to shorter operative time, smaller incision length, and lower blood loss. The reconstructed 3D fracture model could be used to preoperatively determine the surgical windowing and elevating reduction method and simulate the operation for Schatzker type III tibial plateau fractures. PMID:25767804

  16. Development of an aquifer management model AQMAN3D

    USGS Publications Warehouse

    Puig, Juan Carlos; Rolon-Collazo, L. I.; Pagan-Trinidad, Ishmael

    1990-01-01

    A computer code that enables the use of the USGS Modular groundwater flow model for aquifermanagement modeling has been developed. Aquifermanagement techniques integrate groundwater flow modeling with linear quadratic optimization methods for the solution of various aquifer management problems. The model AQMAN3D, is a modified version of a previously developed two-dimensional AQMAN model. The idea of coupling the AQMAN model with the MODULAR model arose because actual groundwater flow systems behave in a three dimensional manner, therefore requiring treatment as such, and due to the widespread use of MODULAR. The use of the AQMAN3D model permits the implementation of the technique known as aquifer managementmodeling. A generalized approach to obtain an optimal solution to an aquifer management problem is proposed, and a sample test problem is presented to illustrate the use of the model. Even though the model provides the hydrologist with a new and powerful investigative tool, its applicability is limited to confined or quasiconfined systems.

  17. Sharing on Web 3d Models of Ancient Theatres. a Methodological Workflow

    NASA Astrophysics Data System (ADS)

    Scianna, A.; La Guardia, M.; Scaduto, M. L.

    2016-06-01

    In the last few years, the need to share on the Web the knowledge of Cultural Heritage (CH) through navigable 3D models has increased. This need requires the availability of Web-based virtual reality systems and 3D WEBGIS. In order to make the information available to all stakeholders, these instruments should be powerful and at the same time very user-friendly. However, research and experiments carried out so far show that a standardized methodology doesn't exist. All this is due both to complexity and dimensions of geometric models to be published, on the one hand, and to excessive costs of hardware and software tools, on the other. In light of this background, the paper describes a methodological approach for creating 3D models of CH, freely exportable on the Web, based on HTML5 and free and open source software. HTML5, supporting the WebGL standard, allows the exploration of 3D spatial models using most used Web browsers like Chrome, Firefox, Safari, Internet Explorer. The methodological workflow here described has been tested for the construction of a multimedia geo-spatial platform developed for three-dimensional exploration and documentation of the ancient theatres of Segesta and of Carthage, and the surrounding landscapes. The experimental application has allowed us to explore the potential and limitations of sharing on the Web of 3D CH models based on WebGL standard. Sharing capabilities could be extended defining suitable geospatial Web-services based on capabilities of HTML5 and WebGL technology.

  18. Active Exploration of Large 3D Model Repositories.

    PubMed

    Gao, Lin; Cao, Yan-Pei; Lai, Yu-Kun; Huang, Hao-Zhi; Kobbelt, Leif; Hu, Shi-Min

    2015-12-01

    With broader availability of large-scale 3D model repositories, the need for efficient and effective exploration becomes more and more urgent. Existing model retrieval techniques do not scale well with the size of the database since often a large number of very similar objects are returned for a query, and the possibilities to refine the search are quite limited. We propose an interactive approach where the user feeds an active learning procedure by labeling either entire models or parts of them as "like" or "dislike" such that the system can automatically update an active set of recommended models. To provide an intuitive user interface, candidate models are presented based on their estimated relevance for the current query. From the methodological point of view, our main contribution is to exploit not only the similarity between a query and the database models but also the similarities among the database models themselves. We achieve this by an offline pre-processing stage, where global and local shape descriptors are computed for each model and a sparse distance metric is derived that can be evaluated efficiently even for very large databases. We demonstrate the effectiveness of our method by interactively exploring a repository containing over 100 K models. PMID:26529460

  19. Cognitive/emotional models for human behavior representation in 3D avatar simulations

    NASA Astrophysics Data System (ADS)

    Peterson, James K.

    2004-08-01

    Simplified models of human cognition and emotional response are presented which are based on models of auditory/ visual polymodal fusion. At the core of these models is a computational model of Area 37 of the temporal cortex which is based on new isocortex models presented recently by Grossberg. These models are trained using carefully chosen auditory (musical sequences), visual (paintings) and higher level abstract (meta level) data obtained from studies of how optimization strategies are chosen in response to outside managerial inputs. The software modules developed are then used as inputs to character generation codes in standard 3D virtual world simulations. The auditory and visual training data also enable the development of simple music and painting composition generators which significantly enhance one's ability to validate the cognitive model. The cognitive models are handled as interacting software agents implemented as CORBA objects to allow the use of multiple language coding choices (C++, Java, Python etc) and efficient use of legacy code.

  20. Modeling tree crown dynamics with 3D partial differential equations.

    PubMed

    Beyer, Robert; Letort, Véronique; Cournède, Paul-Henry

    2014-01-01

    We characterize a tree's spatial foliage distribution by the local leaf area density. Considering this spatially continuous variable allows to describe the spatiotemporal evolution of the tree crown by means of 3D partial differential equations. These offer a framework to rigorously take locally and adaptively acting effects into account, notably the growth toward light. Biomass production through photosynthesis and the allocation to foliage and wood are readily included in this model framework. The system of equations stands out due to its inherent dynamic property of self-organization and spontaneous adaptation, generating complex behavior from even only a few parameters. The density-based approach yields spatially structured tree crowns without relying on detailed geometry. We present the methodological fundamentals of such a modeling approach and discuss further prospects and applications. PMID:25101095

  1. 3D Tissue-Engineered Model of Ewing Sarcoma

    PubMed Central

    Lamhamedi-Cherradi, Salah-Eddine; Santoro, Marco; Ramammoorthy, Vandhana; Menegaz, Brian A.; Bartholomeusz, Geoffrey; Iles, Lakesla R.; Amin, Hesham M.; Livingston, Andrew J.; Mikos, Antonios G.; Ludwig, Joseph A.

    2015-01-01

    Despite longstanding reliance upon monolayer culture for studying cancer cells, and numerous advantages from both a practical and experimental standpoint, a growing body of evidence suggests more complex three-dimensional (3D) models are necessary to properly mimic many of the critical hallmarks associated with the oncogenesis, maintenance and spread of Ewing sarcoma (ES), the second most common pediatric bone tumor. And as clinicians increasingly turn to biologically-targeted therapies that exert their effects not only on the tumor cells themselves, but also on the surrounding extracellular matrix, it is especially important that preclinical models evolve in parallel to reliably measure antineoplastic effects and possible mechanisms of de novo and acquired drug resistance. Herein, we highlight a number of innovative methods used to fabricate biomimetic ES tumors, encompassing both the surrounding cellular milieu and extracellular matrix (ECM), and suggest potential applications to advance our understanding of ES biology, preclinical drug testing, and personalized medicine. PMID:25109853

  2. 3D Model of the Eta Carinae Little Homunculus Nebula

    NASA Astrophysics Data System (ADS)

    Steffen, Wolfgang; Teodoro, Mairan; Madura, Thomas; Groh, Jose H.; Gull, Theodore R.; Corcoran, Michael F.; Damineli, Augusto; Hamaguchi, Kenji

    2015-01-01

    We extend our morpho-kinematic 3D modeling of the Homunculus nebula (Steffen et al., 2014) to the interior nested Little Homunculus. The model is based on spectroscopic observations from HST/STIS. We find that the structure of the interior Little Homunculus is rather flat in the polar regions and interacts with the main Homunculus nebula only on one side, towards the periastron direction of the binary orbit. Furthermore, the two lobes of the LH are misaligned, also towards the periastron direction. As an explanation for the misalignment we propose that, in both cases, shortly after the eruptions that created the bipolar nebulae from the primary star, the off-center wind of the secondary has pushed the ejecta towards the periastron directions, since the secondary is most of the time near the apastron. Future hydrodynamic simulations are warranted to confirm this scenario.

  3. 3D in vitro modeling of the central nervous system

    PubMed Central

    Hopkins, Amy M.; DeSimone, Elise; Chwalek, Karolina; Kaplan, David L.

    2015-01-01

    There are currently more than 600 diseases characterized as affecting the central nervous system (CNS) which inflict neural damage. Unfortunately, few of these conditions have effective treatments available. Although significant efforts have been put into developing new therapeutics, drugs which were promising in the developmental phase have high attrition rates in late stage clinical trials. These failures could be circumvented if current 2D in vitro and in vivo models were improved. 3D, tissue-engineered in vitro systems can address this need and enhance clinical translation through two approaches: (1) bottom-up, and (2) top-down (developmental/regenerative) strategies to reproduce the structure and function of human tissues. Critical challenges remain including biomaterials capable of matching the mechanical properties and extracellular matrix (ECM) composition of neural tissues, compartmentalized scaffolds that support heterogeneous tissue architectures reflective of brain organization and structure, and robust functional assays for in vitro tissue validation. The unique design parameters defined by the complex physiology of the CNS for construction and validation of 3D in vitro neural systems are reviewed here. PMID:25461688

  4. Polygonal Shapes Detection in 3d Models of Complex Architectures

    NASA Astrophysics Data System (ADS)

    Benciolini, G. B.; Vitti, A.

    2015-02-01

    A sequential application of two global models defined on a variational framework is proposed for the detection of polygonal shapes in 3D models of complex architectures. As a first step, the procedure involves the use of the Mumford and Shah (1989) 1st-order variational model in dimension two (gridded height data are processed). In the Mumford-Shah model an auxiliary function detects the sharp changes, i.e., the discontinuities, of a piecewise smooth approximation of the data. The Mumford-Shah model requires the global minimization of a specific functional to simultaneously produce both the smooth approximation and its discontinuities. In the proposed procedure, the edges of the smooth approximation derived by a specific processing of the auxiliary function are then processed using the Blake and Zisserman (1987) 2nd-order variational model in dimension one (edges are processed in the plane). This second step permits to describe the edges of an object by means of piecewise almost-linear approximation of the input edges themselves and to detects sharp changes of the first-derivative of the edges so to detect corners. The Mumford-Shah variational model is used in two dimensions accepting the original data as primary input. The Blake-Zisserman variational model is used in one dimension for the refinement of the description of the edges. The selection among all the boundaries detected by the Mumford-Shah model of those that present a shape close to a polygon is performed by considering only those boundaries for which the Blake-Zisserman model identified discontinuities in their first derivative. The output of the procedure are hence shapes, coming from 3D geometric data, that can be considered as polygons. The application of the procedure is suitable for, but not limited to, the detection of objects such as foot-print of polygonal buildings, building facade boundaries or windows contours. v The procedure is applied to a height model of the building of the Engineering

  5. Advanced prior modeling for 3D bright field electron tomography

    NASA Astrophysics Data System (ADS)

    Sreehari, Suhas; Venkatakrishnan, S. V.; Drummy, Lawrence F.; Simmons, Jeffrey P.; Bouman, Charles A.

    2015-03-01

    Many important imaging problems in material science involve reconstruction of images containing repetitive non-local structures. Model-based iterative reconstruction (MBIR) could in principle exploit such redundancies through the selection of a log prior probability term. However, in practice, determining such a log prior term that accounts for the similarity between distant structures in the image is quite challenging. Much progress has been made in the development of denoising algorithms like non-local means and BM3D, and these are known to successfully capture non-local redundancies in images. But the fact that these denoising operations are not explicitly formulated as cost functions makes it unclear as to how to incorporate them in the MBIR framework. In this paper, we formulate a solution to bright field electron tomography by augmenting the existing bright field MBIR method to incorporate any non-local denoising operator as a prior model. We accomplish this using a framework we call plug-and-play priors that decouples the log likelihood and the log prior probability terms in the MBIR cost function. We specifically use 3D non-local means (NLM) as the prior model in the plug-and-play framework, and showcase high quality tomographic reconstructions of a simulated aluminum spheres dataset, and two real datasets of aluminum spheres and ferritin structures. We observe that streak and smear artifacts are visibly suppressed, and that edges are preserved. Also, we report lower RMSE values compared to the conventional MBIR reconstruction using qGGMRF as the prior model.

  6. Collaboration of 3D context and extracellular matrix in the development of glioma stemness in a 3D model.

    PubMed

    Ma, Nina K L; Lim, Jia Kai; Leong, Meng Fatt; Sandanaraj, Edwin; Ang, Beng Ti; Tang, Carol; Wan, Andrew C A

    2016-02-01

    A hierarchy of cellular stemness exists in certain cancers, and any successful strategy to treat such cancers would have to eliminate the self-renewing tumor-initiating cells at the apex of the hierarchy. The cellular microenvironment, in particular the extracellular matrix (ECM), is believed to have a role in regulating stemness. In this work, U251 glioblastoma cells are cultured on electrospun polystyrene (ESPS) scaffolds coated with an array of 7 laminin isoforms to provide a 3D model for stem cell-related genes and proteins expression studies. We observed collaboration between 3D context and laminins in promoting glioma stemness. Depending on the laminin isoform presented, U251 cells cultured on ESPS scaffolds (3D) exhibited increased expression of stemness markers compared to those cultured on tissue culture polystyrene (2D). Our results indicate the influence of 3D (versus 2D) context on integrin expression, specifically, the upregulation of the laminin-binding integrins alpha 6 and beta 4. By a colony forming assay, we showed enhanced clonogenicity of cells grown on ESPS scaffolds in collaboration with laminins 411, 421, 511 and 521. Evaluation of patient glioma databases demonstrated significant enrichment of integrin and ECM pathway networks in tumors of worse prognosis, consistent with our observations. The present results demonstrate how 3D versus 2D context profoundly affects ECM signaling, leading to stemness. PMID:26684838

  7. 3D density model of the Central Andes

    NASA Astrophysics Data System (ADS)

    Prezzi, Claudia B.; Götze, Hans-Jürgen; Schmidt, Sabine

    2009-12-01

    We developed a 3D density model of the continental crust, the subducted plate and the upper mantle of the Central Andes between 20-29°S and 74-61°W through the forward modelling of Bouguer anomaly. The goal of this contribution is to gain insight on the lithospheric structure integrating the available information (geophysical, geologic, petrologic, and geochemical) in a single model. The geometry of our model is defined and constrained by hypocentre location, reflection and refraction on and offshore seismic lines, travel time and attenuation tomography, receiver function analysis, magnetotelluric studies, thermal models and balanced structural cross-sections. The densities allocated to the different bodies are calculated considering petrologic and geochemical data and pressure and temperature conditions. The model consists of 31 parallel E-W vertical planes, where the continental crust comprises distinct bodies, which represent the different morphotectonic units of the Central Andes. We include a partial melting zone at midcrustal depths under the Altiplano-Puna (low-velocity zone) and consider the presence of a rheologically strong block beneath the Salar de Atacama basin, according to recent seismic studies. Contour maps of the depth of the continental Moho, the thickness of the lower crust and the depth to the bottom of the lithosphere below South America are produced. The possible percentage of partial melt in the Central Andes low-velocity zone is estimated. The residual anomaly is calculated by subtracting from the Bouguer anomaly the gravimetric effect of the modelled subducted slab and of the modelled Moho. Isostatic anomalies are calculated from regional and local isostatic Mohos calculated with and without internal loads, derived from our gravity model, which are then compared to the modelled continental Moho. This study contributes to a more detailed knowledge of the lithospheric structure of this region of the Andes and provides an integrated 3D

  8. Faceless identification: a model for person identification using the 3D shape and 3D motion as cues

    NASA Astrophysics Data System (ADS)

    Klasen, Lena M.; Li, Haibo

    1999-02-01

    Person identification by using biometric methods based on image sequences, or still images, often requires a controllable and cooperative environment during the image capturing stage. In the forensic case the situation is more likely to be the opposite. In this work we propose a method that makes use of the anthropometry of the human body and human actions as cues for identification. Image sequences from surveillance systems are used, which can be seen as monocular image sequences. A 3D deformable wireframe body model is used as a platform to handle the non-rigid information of the 3D shape and 3D motion of the human body from the image sequence. A recursive method for estimating global motion and local shape variations is presented, using two recursive feedback systems.

  9. Brandenburg 3D - a comprehensive 3D Subsurface Model, Conception of an Infrastructure Node and a Web Application

    NASA Astrophysics Data System (ADS)

    Kerschke, Dorit; Schilling, Maik; Simon, Andreas; Wächter, Joachim

    2014-05-01

    The Energiewende and the increasing scarcity of raw materials will lead to an intensified utilization of the subsurface in Germany. Within this context, geological 3D modeling is a fundamental approach for integrated decision and planning processes. Initiated by the development of the European Geospatial Infrastructure INSPIRE, the German State Geological Offices started digitizing their predominantly analog archive inventory. Until now, a comprehensive 3D subsurface model of Brandenburg did not exist. Therefore the project B3D strived to develop a new 3D model as well as a subsequent infrastructure node to integrate all geological and spatial data within the Geodaten-Infrastruktur Brandenburg (Geospatial Infrastructure, GDI-BB) and provide it to the public through an interactive 2D/3D web application. The functionality of the web application is based on a client-server architecture. Server-sided, all available spatial data is published through GeoServer. GeoServer is designed for interoperability and acts as the reference implementation of the Open Geospatial Consortium (OGC) Web Feature Service (WFS) standard that provides the interface that allows requests for geographical features. In addition, GeoServer implements, among others, the high performance certified compliant Web Map Service (WMS) that serves geo-referenced map images. For publishing 3D data, the OGC Web 3D Service (W3DS), a portrayal service for three-dimensional geo-data, is used. The W3DS displays elements representing the geometry, appearance, and behavior of geographic objects. On the client side, the web application is solely based on Free and Open Source Software and leans on the JavaScript API WebGL that allows the interactive rendering of 2D and 3D graphics by means of GPU accelerated usage of physics and image processing as part of the web page canvas without the use of plug-ins. WebGL is supported by most web browsers (e.g., Google Chrome, Mozilla Firefox, Safari, and Opera). The web

  10. The electronic-commerce-oriented virtual merchandise model

    NASA Astrophysics Data System (ADS)

    Fang, Xiaocui; Lu, Dongming

    2004-03-01

    Electronic commerce has been the trend of commerce activities. Providing with Virtual Reality interface, electronic commerce has better expressing capacity and interaction means. But most of the applications of virtual reality technology in EC, 3D model is only the appearance description of merchandises. There is almost no information concerned with commerce information and interaction information. This resulted in disjunction of virtual model and commerce information. So we present Electronic Commerce oriented Virtual Merchandise Model (ECVMM), which combined a model with commerce information, interaction information and figure information of virtual merchandise. ECVMM with abundant information provides better support to information obtainment and communication in electronic commerce.

  11. Optimizing illumination in the greenhouse using a 3D model of tomato and a ray tracer.

    PubMed

    de Visser, Pieter H B; Buck-Sorlin, Gerhard H; van der Heijden, Gerie W A M

    2014-01-01

    Reduction of energy use for assimilation lighting is one of the most urgent goals of current greenhouse horticulture in the Netherlands. In recent years numerous lighting systems have been tested in greenhouses, yet their efficiency has been very difficult to measure in practice. This simulation study evaluated a number of lighting strategies using a 3D light model for natural and artificial light in combination with a 3D model of tomato. The modeling platform GroIMP was used for the simulation study. The crop was represented by 3D virtual plants of tomato with fixed architecture. Detailed data on greenhouse architecture and lamp emission patterns of different light sources were incorporated in the model. A number of illumination strategies were modeled with the calibrated model. Results were compared to the standard configuration. Moreover, adaptation of leaf angles was incorporated for testing their effect on light use efficiency (LUE). A Farquhar photosynthesis model was used to translate the absorbed light for each leaf into a produced amount of carbohydrates. The carbohydrates produced by the crop per unit emitted light from sun or high pressure sodium lamps was the highest for horizontal leaf angles or slightly downward pointing leaves, and was less for more upward leaf orientations. The simulated leaf angles did not affect light absorption from inter-lighting LED modules, but the scenario with LEDs shining slightly upward (20(°)) increased light absorption and LUE relative to default horizontal beaming LEDs. Furthermore, the model showed that leaf orientation more perpendicular to the string of LEDs increased LED light interception. The combination of a ray tracer and a 3D crop model could compute optimal lighting of leaves by quantification of light fluxes and illustration by rendered lighting patterns. Results indicate that illumination efficiency increases when the lamp light is directed at most to leaves that have a high photosynthetic potential. PMID

  12. Optimizing illumination in the greenhouse using a 3D model of tomato and a ray tracer

    PubMed Central

    de Visser, Pieter H. B.; Buck-Sorlin, Gerhard H.; van der Heijden, Gerie W. A. M.

    2014-01-01

    Reduction of energy use for assimilation lighting is one of the most urgent goals of current greenhouse horticulture in the Netherlands. In recent years numerous lighting systems have been tested in greenhouses, yet their efficiency has been very difficult to measure in practice. This simulation study evaluated a number of lighting strategies using a 3D light model for natural and artificial light in combination with a 3D model of tomato. The modeling platform GroIMP was used for the simulation study. The crop was represented by 3D virtual plants of tomato with fixed architecture. Detailed data on greenhouse architecture and lamp emission patterns of different light sources were incorporated in the model. A number of illumination strategies were modeled with the calibrated model. Results were compared to the standard configuration. Moreover, adaptation of leaf angles was incorporated for testing their effect on light use efficiency (LUE). A Farquhar photosynthesis model was used to translate the absorbed light for each leaf into a produced amount of carbohydrates. The carbohydrates produced by the crop per unit emitted light from sun or high pressure sodium lamps was the highest for horizontal leaf angles or slightly downward pointing leaves, and was less for more upward leaf orientations. The simulated leaf angles did not affect light absorption from inter-lighting LED modules, but the scenario with LEDs shining slightly upward (20°) increased light absorption and LUE relative to default horizontal beaming LEDs. Furthermore, the model showed that leaf orientation more perpendicular to the string of LEDs increased LED light interception. The combination of a ray tracer and a 3D crop model could compute optimal lighting of leaves by quantification of light fluxes and illustration by rendered lighting patterns. Results indicate that illumination efficiency increases when the lamp light is directed at most to leaves that have a high photosynthetic potential. PMID

  13. The USGS 3D Seismic Velocity Model for Northern California

    NASA Astrophysics Data System (ADS)

    Brocher, T. M.; Aagaard, B.; Simpson, R. W.; Jachens, R. C.

    2006-12-01

    We present a new regional 3D seismic velocity model for Northern California for use in strong motion simulations of the 1906 San Francisco and other earthquakes. The model includes compressional-wave velocity (Vp), shear-wave velocity (Vs), density, and intrinsic attenuation (Qp, Qs). These properties were assigned for each rock type in a 3D geologic model derived from surface outcrops, boreholes, gravity and magnetic data, and seismic reflection, refraction, and tomography studies. A detailed description of the model, USGS Bay Area Velocity Model 05.1.0, is available online [http://www.sf06simulation.org/geology/velocitymodel]. For ground motion simulations Vs and Qs are more important parameters than Vp and Qp because the strongest ground motions are generated chiefly by shear and surface wave arrivals. Because Vp data are more common than Vs data, however, we first developed Vp versus depth relations for each rock type and then converted these to Vs versus depth relations. For the most important rock types in Northern California we compiled measurements of Vp versus depth using borehole logs, laboratory measurements on hand samples, seismic refraction profiles, and tomography models. These rock types include Salinian and Sierran granitic rocks, metagraywackes and greenstones of the Franciscan Complex, Tertiary and Mesozoic sedimentary and volcanic rocks, and Quaternary and Holocene deposits (Brocher, USGS OFR 05-1317, 2005). Vp versus depth curves were converted to Vs versus depth curves using new empirical nonlinear relations between Vs and Vp (Brocher, BSSA, 2005). These relations, showing that Poisson's ratio is a nonlinear function of Vp, were similarly based on compilations of diverse Vs and Vp measurements on a large suite of rock types, mainly from California and the Pacific Northwest. The model is distributed in a discretized form with routines to query the model using C++, C, and Fortran 77 programming languages. The geologic model was discretized at

  14. A 3D Bubble Merger Model for RTI Mixing

    NASA Astrophysics Data System (ADS)

    Cheng, Baolian

    2015-11-01

    In this work we present a model for the merger processes of bubbles at the edge of an unstable acceleration driven mixing layer. Steady acceleration defines a self-similar mixing process, with a time-dependent inverse cascade of structures of increasing size. The time evolution is itself a renormalization group evolution. The model predicts the growth rate of a Rayleigh-Taylor chaotic fluid-mixing layer. The 3-D model differs from the 2-D merger model in several important ways. Beyond the extension of the model to three dimensions, the model contains one phenomenological parameter, the variance of the bubble radii at fixed time. The model also predicts several experimental numbers: the bubble mixing rate, the mean bubble radius, and the bubble height separation at the time of merger. From these we also obtain the bubble height to the radius aspect ratio, which is in good agreement with experiments. Applications to recent NIF and Omega experiments will be discussed. This work was performed under the auspices of the U.S. Department of Energy by the Los Alamos National Laboratory under Contract No. W-7405-ENG-36.

  15. 3-D numerical modeling of plume-induced subduction initiation

    NASA Astrophysics Data System (ADS)

    Baes, Marzieh; Gerya, taras; Sobolev, Stephan

    2016-04-01

    Investigation of mechanisms involved in formation of a new subduction zone can help us to better understand plate tectonics. Despite numerous previous studies, it is still unclear how and where an old oceanic plate starts to subduct beneath the other plate. One of the proposed scenarios for nucleation of subduction is plume-induced subduction initiation, which was investigated in detail, using 2-D models, by Ueda et al. (2008). Recently. Gerya et al. (2015), using 3D numerical models, proposed that plume-lithosphere interaction in the Archean led to the subduction initiation and onset of plate tectonic. In this study, we aim to pursue work of Ueda et al. (2008) by incorporation of 3-D thermo-mechanical models to investigate conditions leading to oceanic subduction initiation as a result of thermal-chemical mantle plume-lithosphere interaction in the modern earth. Results of our experiments show four different deformation regimes in response to plume-lithosphere interaction, that are a) self-sustaining subduction initiation where subduction becomes self-sustained, b) freezing subduction initiation where subduction stops at shallow depths, c) slab break-off where subducting circular slab breaks off soon after formation and d) plume underplating where plume does not pass through the lithosphere but spreads beneath it (failed subduction initiation). These different regimes depend on several parameters such as plume's size, composition and temperature, lithospheric brittle/plastic strength, age of the oceanic lithosphere and presence/absence of lithospheric heterogeneities. Results show that subduction initiates and becomes self-sustained when lithosphere is older than 10 Myr and non-dimensional ratio of the plume buoyancy force and lithospheric strength above the plume is higher than 2.

  16. 3D model generation using an airborne swarm

    NASA Astrophysics Data System (ADS)

    Clark, R. A.; Punzo, G.; Dobie, G.; MacLeod, C. N.; Summan, R.; Pierce, G.; Macdonald, M.; Bolton, G.

    2015-03-01

    Using an artificial kinematic field to provide co-ordination between multiple inspection UAVs, the authors herein demonstrate full 3D modelling capability based on a photogrammetric system. The operation of the system is demonstrated by generating a full 3D surface model of an intermediate level nuclear waste storage drum. Such drums require periodic inspection to ensure that drum distortion or corrosion is carefully monitored. Performing this inspection with multiple airborne platforms enables rapid inspection of structures that are inaccessible to on-surface remote vehicles and are in human-hazardous environments. A three-dimensional surface-meshed model of the target can then be constructed in post-processing through photogrammetry analysis of the visual inspection data. The inspection environment uses a tracking system to precisely monitor the position of each aerial vehicle within the enclosure. The vehicles used are commercially available Parrot AR. Drone quadcopters, controlled through a computer interface connected over an IEEE 802.11n (WiFi) network, implementing a distributed controller for each vehicle. This enables the autonomous and distributed elements of the control scheme to be retained, while alleviating the vehicles of the control algorithm's computational load. The control scheme relies on a kinematic field defined with the target at its centre. This field defines the trajectory for all the drones in the volume relative to the central target, enabling the drones to circle the target at a set radius while avoiding drone collisions. This function enables complete coverage along the height of the object, which is assured by transitioning to another inspection band only after completing circumferential coverage. Using a swarm of vehicles, the time until complete coverage can be significantly reduced.

  17. 3D model generation using an airborne swarm

    SciTech Connect

    Clark, R. A.; Punzo, G.; Macdonald, M.; Dobie, G.; MacLeod, C. N.; Summan, R.; Pierce, G.; Bolton, G.

    2015-03-31

    Using an artificial kinematic field to provide co-ordination between multiple inspection UAVs, the authors herein demonstrate full 3D modelling capability based on a photogrammetric system. The operation of the system is demonstrated by generating a full 3D surface model of an intermediate level nuclear waste storage drum. Such drums require periodic inspection to ensure that drum distortion or corrosion is carefully monitored. Performing this inspection with multiple airborne platforms enables rapid inspection of structures that are inaccessible to on-surface remote vehicles and are in human-hazardous environments. A three-dimensional surface-meshed model of the target can then be constructed in post-processing through photogrammetry analysis of the visual inspection data. The inspection environment uses a tracking system to precisely monitor the position of each aerial vehicle within the enclosure. The vehicles used are commercially available Parrot AR. Drone quadcopters, controlled through a computer interface connected over an IEEE 802.11n (WiFi) network, implementing a distributed controller for each vehicle. This enables the autonomous and distributed elements of the control scheme to be retained, while alleviating the vehicles of the control algorithm’s computational load. The control scheme relies on a kinematic field defined with the target at its centre. This field defines the trajectory for all the drones in the volume relative to the central target, enabling the drones to circle the target at a set radius while avoiding drone collisions. This function enables complete coverage along the height of the object, which is assured by transitioning to another inspection band only after completing circumferential coverage. Using a swarm of vehicles, the time until complete coverage can be significantly reduced.

  18. Automatic 360-deg profilometry of a 3D object using a shearing interferometer and virtual grating

    NASA Astrophysics Data System (ADS)

    Zhang, Yong-Lin; Bu, Guixue

    1996-10-01

    Phase measuring technique has been widely used in optical precision inspection for its extraordinary advantage. We use the phase-measuring technique and design a practical instrument for measuring 360 degrees profile of 3D object. A novel method that can realize profile detection with higher speed and lower cost is proposed. Phase unwrapping algorithm based on the second order differentiation is developed. A complete 3D shape is reconstructed from a series of line- section profiles corresponding to discrete angular position of the object. The profile-jointing procedure is only related with two fixed parameters and coordination transformation.

  19. D Recording for 2d Delivering - the Employment of 3d Models for Studies and Analyses -

    NASA Astrophysics Data System (ADS)

    Rizzi, A.; Baratti, G.; Jiménez, B.; Girardi, S.; Remondino, F.

    2011-09-01

    In the last years, thanks to the advances of surveying sensors and techniques, many heritage sites could be accurately replicated in digital form with very detailed and impressive results. The actual limits are mainly related to hardware capabilities, computation time and low performance of personal computer. Often, the produced models are not visible on a normal computer and the only solution to easily visualized them is offline using rendered videos. This kind of 3D representations is useful for digital conservation, divulgation purposes or virtual tourism where people can visit places otherwise closed for preservation or security reasons. But many more potentialities and possible applications are available using a 3D model. The problem is the ability to handle 3D data as without adequate knowledge this information is reduced to standard 2D data. This article presents some surveying and 3D modeling experiences within the APSAT project ("Ambiente e Paesaggi dei Siti d'Altura Trentini", i.e. Environment and Landscapes of Upland Sites in Trentino). APSAT is a multidisciplinary project funded by the Autonomous Province of Trento (Italy) with the aim documenting, surveying, studying, analysing and preserving mountainous and hill-top heritage sites located in the region. The project focuses on theoretical, methodological and technological aspects of the archaeological investigation of mountain landscape, considered as the product of sequences of settlements, parcelling-outs, communication networks, resources, and symbolic places. The mountain environment preserves better than others the traces of hunting and gathering, breeding, agricultural, metallurgical, symbolic activities characterised by different lengths and environmental impacts, from Prehistory to the Modern Period. Therefore the correct surveying and documentation of this heritage sites and material is very important. Within the project, the 3DOM unit of FBK is delivering all the surveying and 3D material to

  20. Crashworthiness analysis using advanced material models in DYNA3D

    SciTech Connect

    Logan, R.W.; Burger, M.J.; McMichael, L.D.; Parkinson, R.D.

    1993-10-22

    As part of an electric vehicle consortium, LLNL and Kaiser Aluminum are conducting experimental and numerical studies on crashworthy aluminum spaceframe designs. They have jointly explored the effect of heat treat on crush behavior and duplicated the experimental behavior with finite-element simulations. The major technical contributions to the state of the art in numerical simulation arise from the development and use of advanced material model descriptions for LLNL`s DYNA3D code. Constitutive model enhancements in both flow and failure have been employed for conventional materials such as low-carbon steels, and also for lighter weight materials such as aluminum and fiber composites being considered for future vehicles. The constitutive model enhancements are developed as extensions from LLNL`s work in anisotropic flow and multiaxial failure modeling. Analysis quality as a function of level of simplification of material behavior and mesh is explored, as well as the penalty in computation cost that must be paid for using more complex models and meshes. The lightweight material modeling technology is being used at the vehicle component level to explore the safety implications of small neighborhood electric vehicles manufactured almost exclusively from these materials.

  1. TRANSL8GDECIM8. Data Translation and Filtering for Large 3D Triangle Mesh Models

    SciTech Connect

    Janucik, F.X.; Ross, D.M.

    1993-09-01

    The TRANSL8GDECIM8 system consists of two programs: TRANSL8G and DECIM8. The TRANSL8G program facilitates the interchange, topology generation, error checking, and enhancement of large 3D triangle meshes. Such data is frequently used to represent conceptual designs, scientific visualization volume modeling, or discrete sample data. Interchange is provided between several popular commercial and defacto standard geometry formats. Error checking is included to identify duplicate and zero area triangles. Model enhancement features include common vertex joining, consistent triangle vertex ordering, vertex normal vector averaging, and triangle strip generation. Many of the traditional O(n squared) algorithms required to provide the above features have been recast and are O(n) which support large mesh sizes. The DECIM8 program is based on a data filter algorithm that significantly reduces the number of triangles required to represent three dimensional (3D) models of geometry, scientific visualization results, and discretely sampled data. The algorithm uses a combined incremental and iterative strategy. It eliminates local patches of triangles whose geometries are not appreciably different and replaces them with fewer larger triangles. The algorithm has been used to reduce triangles in large conceptual design models to facilitate virtual walk throughs and to enable interactive viewing of large 3D iso-surface volume visualizations.

  2. 3D Printed Molecules and Extended Solid Models for Teaching Symmetry and Point Groups

    ERIC Educational Resources Information Center

    Scalfani, Vincent F.; Vaid, Thomas P.

    2014-01-01

    Tangible models help students and researchers visualize chemical structures in three dimensions (3D). 3D printing offers a unique and straightforward approach to fabricate plastic 3D models of molecules and extended solids. In this article, we prepared a series of digital 3D design files of molecular structures that will be useful for teaching…

  3. Quality of Grasping and the Role of Haptics in a 3-D Immersive Virtual Reality Environment in Individuals With Stroke.

    PubMed

    Levin, Mindy F; Magdalon, Eliane C; Michaelsen, Stella M; Quevedo, Antonio A F

    2015-11-01

    Reaching and grasping parameters with and without haptic feedback were characterized in people with chronic post-stroke behaviors. Twelve (67 ± 10 years) individuals with chronic stroke and arm/hand paresis (Fugl-Meyer Assessment-Arm: ≥ 46/66 pts) participated. Three dimensional (3-D) temporal and spatial kinematics of reaching and grasping movements to three objects (can: cylindrical grasp; screwdriver: power grasp; pen: precision grasp) in a physical environment (PE) with and without additional haptic feedback and a 3-D virtual environment (VE) with haptic feedback were recorded. Participants reached, grasped and transported physical and virtual objects using similar movement strategies in all conditions. Reaches made in VE were less smooth and slower compared to the PE. Arm and trunk kinematics were similar in both environments and glove conditions. For grasping, stroke subjects preserved aperture scaling to object size but used wider hand apertures with longer delays between times to maximal reaching velocity and maximal grasping aperture. Wearing the glove decreased reaching velocity. Our results in a small group of subjects suggest that providing haptic information in the VE did not affect the validity of reaching and grasping movement. Small disparities in movement parameters between environments may be due to differences in perception of object distance in VE. Reach-to-grasp kinematics to smaller objects may be improved by better 3-D rendering. Comparable kinematics between environments and conditions is encouraging for the incorporation of high quality VEs in rehabilitation programs aimed at improving upper limb recovery. PMID:25594971

  4. Energy flow in passive and active 3D cochlear model

    SciTech Connect

    Wang, Yanli; Steele, Charles; Puria, Sunil

    2015-12-31

    Energy flow in the cochlea is an important characteristic of the cochlear traveling wave, and many investigators, such as von Békésy and Lighthill, have discussed this phenomenon. Particularly after the discovery of the motility of the outer hair cells (OHCs), the nature of the power gain of the cochlea has been a fundamental research question. In the present work, direct three-dimensional (3D) calculations of the power on cross sections of the cochlea and on the basilar membrane are performed based on a box model of the mouse cochlea. The distributions of the fluid pressure and fluid velocity in the scala vestibuli are presented. The power output from the OHCs and the power loss due to fluid viscous damping are calculated along the length of the cochlea. This work provides a basis for theoretical calculations of the power gain of the OHCs from mechanical considerations.

  5. Energy flow in passive and active 3D cochlear model

    NASA Astrophysics Data System (ADS)

    Wang, Yanli; Puria, Sunil; Steele, Charles

    2015-12-01

    Energy flow in the cochlea is an important characteristic of the cochlear traveling wave, and many investigators, such as von Békésy and Lighthill, have discussed this phenomenon. Particularly after the discovery of the motility of the outer hair cells (OHCs), the nature of the power gain of the cochlea has been a fundamental research question. In the present work, direct three-dimensional (3D) calculations of the power on cross sections of the cochlea and on the basilar membrane are performed based on a box model of the mouse cochlea. The distributions of the fluid pressure and fluid velocity in the scala vestibuli are presented. The power output from the OHCs and the power loss due to fluid viscous damping are calculated along the length of the cochlea. This work provides a basis for theoretical calculations of the power gain of the OHCs from mechanical considerations.

  6. 3D Model of the San Emidio Geothermal Area

    SciTech Connect

    James E. Faulds

    2013-12-31

    The San Emidio geothermal system is characterized by a left-step in a west-dipping normal fault system that bounds the western side of the Lake Range. The 3D geologic model consists of 5 geologic units and 55 faults. Overlying Jurrassic-Triassic metasedimentary basement is a ~500 m-1000 m thick section of the Miocene lower Pyramid sequence, pre- syn-extensional Quaternary sedimentary rocks and post-extensional Quaternary rocks. 15-30º eastward dip of the stratigraphy is controlled by the predominant west-dipping fault set. Both geothermal production and injection are concentrated north of the step over in an area of closely spaced west dipping normal faults.

  7. 3D lithography modeling for ground rule development

    NASA Astrophysics Data System (ADS)

    Sarma, Chandra; Bailey, Todd; Lyons, Adam; Shao, Dongbing

    2011-04-01

    The ability to incorporate the effect of patterned underlayers in a 3-dimensional physical resist model that truly mimics the process on real wafers could be used to formulate robust ground rules for design. We have shown as an example block level simulations, where the resist critical dimension is determined by the presence of STI (shallow trench isolation) and/or patterned gate level underneath & their relative spacing, as confirmed on wafer. We will demonstrate how the results of such study could be used for creating ground rules which are truly dependent on the interaction between the current layer resist & the patterned layers underneath. We have also developed a new way to visualize lithographic process variations in 3-D space that is useful for simulation analysis that can prove very helpful in ground rule development and process optimization. Such visualization capability in the dataprep flow to flag issues or dispose critical structures increases speed and efficiency in the mask tapeout process.

  8. Massive fermion model in 3d and higher spin currents

    NASA Astrophysics Data System (ADS)

    Bonora, L.; Cvitan, M.; Prester, P. Dominis; de Souza, B. Lima; Smolić, I.

    2016-05-01

    We analyze the 3d free massive fermion theory coupled to external sources. The presence of a mass explicitly breaks parity invariance. We calculate two- and three-point functions of a gauge current and the energy momentum tensor and, for instance, obtain the well-known result that in the IR limit (but also in the UV one) we reconstruct the relevant CS action. We then couple the model to higher spin currents and explicitly work out the spin 3 case. In the UV limit we obtain an effective action which was proposed many years ago as a possible generalization of spin 3 CS action. In the IR limit we derive a different higher spin action. This analysis can evidently be generalized to higher spins. We also discuss the conservation and properties of the correlators we obtain in the intermediate steps of our derivation.

  9. 3D Model of the Neal Hot Springs Geothermal Area

    DOE Data Explorer

    Faulds, James E.

    2013-12-31

    The Neal Hot Springs geothermal system lies in a left-step in a north-striking, west-dipping normal fault system, consisting of the Neal Fault to the south and the Sugarloaf Butte Fault to the north (Edwards, 2013). The Neal Hot Springs 3D geologic model consists of 104 faults and 13 stratigraphic units. The stratigraphy is sub-horizontal to dipping <10 degrees and there is no predominant dip-direction. Geothermal production is exclusively from the Neal Fault south of, and within the step-over, while geothermal injection is into both the Neal Fault to the south of the step-over and faults within the step-over.

  10. Proteopedia: A Collaborative, Virtual 3D Web-Resource for Protein and Biomolecule Structure and Function

    ERIC Educational Resources Information Center

    Hodis, Eran; Prilusky, Jaime, Sussman, Joel L.

    2010-01-01

    Protein structures are hard to represent on paper. They are large, complex, and three-dimensional (3D)--four-dimensional if conformational changes count! Unlike most of their substrates, which can easily be drawn out in full chemical formula, drawing every atom in a protein would usually be a mess. Simplifications like showing only the surface of…

  11. 3D Model of the Tuscarora Geothermal Area

    DOE Data Explorer

    Faulds, James E.

    2013-12-31

    The Tuscarora geothermal system sits within a ~15 km wide left-step in a major west-dipping range-bounding normal fault system. The step over is defined by the Independence Mountains fault zone and the Bull Runs Mountains fault zone which overlap along strike. Strain is transferred between these major fault segments via and array of northerly striking normal faults with offsets of 10s to 100s of meters and strike lengths of less than 5 km. These faults within the step over are one to two orders of magnitude smaller than the range-bounding fault zones between which they reside. Faults within the broad step define an anticlinal accommodation zone wherein east-dipping faults mainly occupy western half of the accommodation zone and west-dipping faults lie in the eastern half of the accommodation zone. The 3D model of Tuscarora encompasses 70 small-offset normal faults that define the accommodation zone and a portion of the Independence Mountains fault zone, which dips beneath the geothermal field. The geothermal system resides in the axial part of the accommodation, straddling the two fault dip domains. The Tuscarora 3D geologic model consists of 10 stratigraphic units. Unconsolidated Quaternary alluvium has eroded down into bedrock units, the youngest and stratigraphically highest bedrock units are middle Miocene rhyolite and dacite flows regionally correlated with the Jarbidge Rhyolite and modeled with uniform cumulative thickness of ~350 m. Underlying these lava flows are Eocene volcanic rocks of the Big Cottonwood Canyon caldera. These units are modeled as intracaldera deposits, including domes, flows, and thick ash deposits that change in thickness and locally pinch out. The Paleozoic basement of consists metasedimenary and metavolcanic rocks, dominated by argillite, siltstone, limestone, quartzite, and metabasalt of the Schoonover and Snow Canyon Formations. Paleozoic formations are lumped in a single basement unit in the model. Fault blocks in the eastern

  12. A 3D parallel model of Ganymede's exosphere

    NASA Astrophysics Data System (ADS)

    Leclercq, Ludivine; Turc, Lucile; François, Leblanc; Ronan, Modolo

    2013-04-01

    Ganymede is a unique object : it is the biggest moon of our solar system, and the only satellite which has its own intrinsic magnetic field. Its surface is covered by water ice and by regolith. Some previous observations suggest that below its surface may exist an ocean of liquid water. The atmosphere of the planet is poorly known but should be composed essentially of water, hydrogen and oxygen (Marconi et al., Icarus, 2007). These atmospheric particles mainly originate from the surface thanks to sublimation of water-ice and sputtering, a process driven by the magnetospheric Jovian particles impacting Ganymede surface and leading to ejection of atoms and molecules into Ganymede atmosphere. We developed a model of Ganymede's atmosphere based on a 3D Monte Carlo description of the fate of the ejected particles from the surface. This model has been parallelized allowing a much better statistical, spatial and temporal description of Ganymede's environment. This model includes the main sources of the neutral atmosphere and is able to calculate all its characteristics. It was successfully compared to the few known observations as well as to previous modeling. In this presentation, we will present the main characteristics of this model and what it tells us on Ganymede's atmosphere, in terms of spatial structure, composition, temporal variability and relations with both magnetosphere and surface.

  13. Virtually supportive: A feasibility pilot study of an online support group for dementia caregivers in a 3D virtual environment

    PubMed Central

    O’Connor, Mary-Frances; Arizmendi, Brian J.; Kaszniak, Alfred W.

    2014-01-01

    Caregiver support groups effectively reduce stress from caring for someone with dementia. These same demands can prevent participation in a group. The present feasibility study investigated a virtual online caregiver support group to bring the support group into the home. While online groups have been shown to be helpful, submissions to a message board (vs. live conversation) can feel impersonal. By using avatars, participants interacted via real-time chat in a virtual environment in an 8-week support group. Data indicated lower levels of perceived stress, depression and loneliness across participants. Importantly, satisfaction reports also indicate that caregivers overcame the barriers to participation, and had a strong sense of the group’s presence. This study provides the framework for an accessible and low cost online support group for a dementia caregiver. The study demonstrates the feasibility of interactive group in a virtual environment for engaging members in meaningful interaction. PMID:24984911

  14. Modeling Electric Current Flow in 3D Fractured Media

    NASA Astrophysics Data System (ADS)

    Demirel, S.; Roubinet, D.; Irving, J.

    2014-12-01

    The study of fractured rocks is extremely important in a variety of research fields and applications such as hydrogeology, hydrocarbon extraction and long-term storage of toxic waste. As fractures are highly conductive structures in comparison to the surrounding rock, their presence can be either an advantage or a drawback. For hydrocarbon extraction, fractures allow for quick and easy access to the resource whereas for toxic waste storage their presence increases the risk of leakage and migration of pollutants. In both cases, the identification of fracture network characteristics is an essential step. Recently, we have developed an approach for modeling electric current flow in 2D fractured media. This approach is based on a discrete-dual-porosity model where fractures are represented explicitly, the matrix is coarsely discretized into blocks, and current flow exchange between the fractures and matrix is analytically evaluated at the fracture-scale and integrated at the block-scale [1]. Although this approach has shown much promise and has proven its efficiency for 2D simulations, its extension to 3D remains to be addressed. To this end, we assume that fractures can be represented as two-dimensional finite planes embedded in the surrounding matrix, and we express analytically the distribution of electric potential at the fracture scale. This fracture-scale expression takes into account the electric-current-flow exchange with the surrounding matrix and flow conservation is enforced at the fracture intersections. The fracture-matrix exchange is then integrated at the matrix-block scale where the electric current flow conservation at the block boundaries is formulated with a modified finite volume method. With the objective of providing a low-computational-cost modeling approach adapted to 3D simulations in fractured media, our model is (i) validated and compared to existing modeling approaches and, (ii) used to evaluate the impact of the presence of fractures on

  15. A hybrid-3D hillslope hydrological model for use in Earth system models

    NASA Astrophysics Data System (ADS)

    Hazenberg, P.; Fang, Y.; Broxton, P.; Gochis, D.; Niu, G.-Y.; Pelletier, J. D.; Troch, P. A.; Zeng, X.

    2015-10-01

    Hillslope-scale rainfall-runoff processes leading to a fast catchment response are not explicitly included in land surface models (LSMs) for use in earth system models (ESMs) due to computational constraints. This study presents a hybrid-3D hillslope hydrological model (h3D) that couples a 1-D vertical soil column model with a lateral pseudo-2D saturated zone and overland flow model for use in ESMs. By representing vertical and lateral responses separately at different spatial resolutions, h3D is computationally efficient. The h3D model was first tested for three different hillslope planforms (uniform, convergent and divergent). We then compared h3D (with single and multiple soil columns) with a complex physically based 3-D model and a simple 1-D soil moisture model coupled with an unconfined aquifer (as typically used in LSMs). It is found that simulations obtained by the simple 1-D model vary considerably from the complex 3-D model and are not able to represent hillslope-scale variations in the lateral flow response. In contrast, the single soil column h3D model shows a much better performance and saves computational time by 2-3 orders of magnitude compared with the complex 3-D model. When multiple vertical soil columns are implemented, the resulting hydrological responses (soil moisture, water table depth, and base flow along the hillslope) from h3D are nearly identical to those predicted by the complex 3-D model, but still saves computational time. As such, the computational efficiency of the h3D model provides a valuable and promising approach to incorporating hillslope-scale hydrological processes into continental and global-scale ESMs.

  16. Efficient sensitivity computations in 3D air quality models

    NASA Astrophysics Data System (ADS)

    Kioutsioukis, Ioannis; Melas, Dimitrios; Zerefos, Christos; Ziomas, Ioannis

    2005-04-01

    The prediction of ground level ozone for air quality monitoring and assessment is simulated through an integrated system of gridded models (meteorological, photochemical), where the atmosphere is represented with a three-dimensional grid that may include thousands of grid cells. The continuity equation solved by the Photochemical Air Quality Model (PAQM) reproduces the atmospheric processes (dynamical, physical, chemical and radiative), such as moving and mixing air parcels from one grid cell to another, calculating chemical reactions, injecting new emissions. The whole modeling procedure includes several sources of uncertainty, especially in the large data sets that describe the status of the domain (boundary conditions, emissions, chemical reaction rates and several others). The robustness of the photochemical simulation is addressed in this work through the deterministic approach of sensitivity analysis. The automatic differentiation tool ADIFOR is applied on the 3D PAQM CAMx and augments its Fortran 77 code by introducing new lines of code that additionally calculate, in only one run, the gradient of the solution vector with respect to its input parameters. The applicability of the approach is evaluated through a sensitivity study of the modeled concentrations to perturbations at the boundary conditions and the emissions, for three essentially dissimilar European Metropolises of the Auto-Oil II programme (Athens, Milan, and London).

  17. Indoor Modelling Benchmark for 3D Geometry Extraction

    NASA Astrophysics Data System (ADS)

    Thomson, C.; Boehm, J.

    2014-06-01

    A combination of faster, cheaper and more accurate hardware, more sophisticated software, and greater industry acceptance have all laid the foundations for an increased desire for accurate 3D parametric models of buildings. Pointclouds are the data source of choice currently with static terrestrial laser scanning the predominant tool for large, dense volume measurement. The current importance of pointclouds as the primary source of real world representation is endorsed by CAD software vendor acquisitions of pointcloud engines in 2011. Both the capture and modelling of indoor environments require great effort in time by the operator (and therefore cost). Automation is seen as a way to aid this by reducing the workload of the user and some commercial packages have appeared that provide automation to some degree. In the data capture phase, advances in indoor mobile mapping systems are speeding up the process, albeit currently with a reduction in accuracy. As a result this paper presents freely accessible pointcloud datasets of two typical areas of a building each captured with two different capture methods and each with an accurate wholly manually created model. These datasets are provided as a benchmark for the research community to gauge the performance and improvements of various techniques for indoor geometry extraction. With this in mind, non-proprietary, interoperable formats are provided such as E57 for the scans and IFC for the reference model. The datasets can be found at: http://indoor-bench.github.io/indoor-bench.

  18. 3-D Eutrophication Modeling for Lake Simcoe, Canada

    NASA Astrophysics Data System (ADS)

    Lu, Q.; Duckett, F.; Nairn, R.; Brunton, A.

    2006-12-01

    The Lake Simcoe Region Conservation Authority (LSRCA) and the Province of Ontario are undertaking a series of studies to facilitate management of the pressures of population growth in the Lake Simcoe watershed. With rapid population growth and urban development comes additional land clearing, storm water runoff and the discharge of treated sewage, all of which are sources of increased phosphorus loading to Lake Simcoe. Depressed oxygen levels were linked to phosphorous enrichment of the lake, with the resultant stimulation of algal growth in the sunlit upper waters of the lake, and its subsequent senescence and settling into the hypolimnion where bacterial decomposition consumes oxygen from the stratified waters. This poster describes a 3-D hydrodynamic, thermal and water quality model of Lake Simcoe developed using the Danish Hydraulics Institute (DHI) MIKE3 model. The hydrodynamic module includes wind-driven circulation, temperature variation, development of the thermocline and thermal stratification, and hydraulic forcing from inflowing tributaries. This is linked to the water quality module which simulates the eutrophication processes in the response of the lake to loadings of phosphorus, such as algal growth, the growth of aquatic plants and subsequent oxygen consumption. The model has been calibrated against Acoustic Doppler Current Profiler velocity data, plus measured temperature and water quality data at MOE stations in the lake and water intakes. The model is an important assessment tool for the management of the lake and its watersheds, allowing assessment of the impacts of the urban growth and land use change on the water quality in Lake Simcoe.

  19. Energy-Based Pharmacophore and Three-Dimensional Quantitative Structure--Activity Relationship (3D-QSAR) Modeling Combined with Virtual Screening To Identify Novel Small-Molecule Inhibitors of Silent Mating-Type Information Regulation 2 Homologue 1 (SIRT1).

    PubMed

    Pulla, Venkat Koushik; Sriram, Dinavahi Saketh; Viswanadha, Srikant; Sriram, Dharmarajan; Yogeeswari, Perumal

    2016-01-25

    Silent mating-type information regulation 2 homologue 1 (SIRT1), being the homologous enzyme of silent information regulator-2 gene in yeast, has multifaceted functions. It deacetylates a wide range of histone and nonhistone proteins; hence, it has good therapeutic importance. SIRT1 was believed to be overexpressed in many cancers (prostate, colon) and inflammatory disorders (rheumatoid arthritis). Hence, designing inhibitors against SIRT1 could be considered valuable. Both structure-based and ligand-based drug design strategies were employed to design novel inhibitors utilizing high-throughput virtual screening of chemical databases. An energy-based pharmacophore was generated using the crystal structure of SIRT1 bound with a small molecule inhibitor and compared with a ligand-based pharmacophore model that showed four similar features. A three-dimensional quantitative structure-activity relationship (3D-QSAR) model was developed and validated to be employed in the virtual screening protocol. Among the designed compounds, Lead 17 emerged as a promising SIRT1 inhibitor with IC50 of 4.34 μM and, at nanomolar concentration (360 nM), attenuated the proliferation of prostate cancer cells (LnCAP). In addition, Lead 17 significantly reduced production of reactive oxygen species, thereby reducing pro inflammatory cytokines such as IL6 and TNF-α. Furthermore, the anti-inflammatory potential of the compound was ascertained using an animal paw inflammation model induced by carrageenan. Thus, the identified SIRT1 inhibitors could be considered as potent leads to treat both cancer and inflammation. PMID:26636371

  20. Planetary subsurface investigation by 3D visualization model .

    NASA Astrophysics Data System (ADS)

    Seu, R.; Catallo, C.; Tragni, M.; Abbattista, C.; Cinquepalmi, L.

    Subsurface data analysis and visualization represents one of the main aspect in Planetary Observation (i.e. search for water or geological characterization). The data are collected by subsurface sounding radars as instruments on-board of deep space missions. These data are generally represented as 2D radargrams in the perspective of space track and z axes (perpendicular to the subsurface) but without direct correlation to other data acquisition or knowledge on the planet . In many case there are plenty of data from other sensors of the same mission, or other ones, with high continuity in time and in space and specially around the scientific sites of interest (i.e. candidate landing areas or particular scientific interesting sites). The 2D perspective is good to analyse single acquisitions and to perform detailed analysis on the returned echo but are quite useless to compare very large dataset as now are available on many planets and moons of solar system. The best way is to approach the analysis on 3D visualization model generated from the entire stack of data. First of all this approach allows to navigate the subsurface in all directions and analyses different sections and slices or moreover navigate the iso-surfaces respect to a value (or interval). The last one allows to isolate one or more iso-surfaces and remove, in the visualization mode, other data not interesting for the analysis; finally it helps to individuate the underground 3D bodies. Other aspect is the needs to link the on-ground data, as imaging, to the underground one by geographical and context field of view.

  1. Realistic texture extraction for 3D face models robust to self-occlusion

    NASA Astrophysics Data System (ADS)

    Qu, Chengchao; Monari, Eduardo; Schuchert, Tobias; Beyerer, Jürgen

    2015-02-01

    In the context of face modeling, probably the most well-known approach to represent 3D faces is the 3D Morphable Model (3DMM). When 3DMM is fitted to a 2D image, the shape as well as the texture and illumination parameters are simultaneously estimated. However, if real facial texture is needed, texture extraction from the 2D image is necessary. This paper addresses the possible problems in texture extraction of a single image caused by self-occlusion. Unlike common approaches that leverage the symmetric property of the face by mirroring the visible facial part, which is sensitive to inhomogeneous illumination, this work first generates a virtual texture map for the skin area iteratively by averaging the color of neighbored vertices. Although this step creates unrealistic, overly smoothed texture, illumination stays constant between the real and virtual texture. In the second pass, the mirrored texture is gradually blended with the real or generated texture according to the visibility. This scheme ensures a gentle handling of illumination and yet yields realistic texture. Because the blending area only relates to non-informative area, main facial features still have unique appearance in different face halves. Evaluation results reveal realistic rendering in novel poses robust to challenging illumination conditions and small registration errors.

  2. Accurate, low-cost 3D-models of gullies

    NASA Astrophysics Data System (ADS)

    Onnen, Nils; Gronz, Oliver; Ries, Johannes B.; Brings, Christine

    2015-04-01

    Soil erosion is a widespread problem in arid and semi-arid areas. The most severe form is the gully erosion. They often cut into agricultural farmland and can make a certain area completely unproductive. To understand the development and processes inside and around gullies, we calculated detailed 3D-models of gullies in the Souss Valley in South Morocco. Near Taroudant, we had four study areas with five gullies different in size, volume and activity. By using a Canon HF G30 Camcorder, we made varying series of Full HD videos with 25fps. Afterwards, we used the method Structure from Motion (SfM) to create the models. To generate accurate models maintaining feasible runtimes, it is necessary to select around 1500-1700 images from the video, while the overlap of neighboring images should be at least 80%. In addition, it is very important to avoid selecting photos that are blurry or out of focus. Nearby pixels of a blurry image tend to have similar color values. That is why we used a MATLAB script to compare the derivatives of the images. The higher the sum of the derivative, the sharper an image of similar objects. MATLAB subdivides the video into image intervals. From each interval, the image with the highest sum is selected. E.g.: 20min. video at 25fps equals 30.000 single images. The program now inspects the first 20 images, saves the sharpest and moves on to the next 20 images etc. Using this algorithm, we selected 1500 images for our modeling. With VisualSFM, we calculated features and the matches between all images and produced a point cloud. Then, MeshLab has been used to build a surface out of it using the Poisson surface reconstruction approach. Afterwards we are able to calculate the size and the volume of the gullies. It is also possible to determine soil erosion rates, if we compare the data with old recordings. The final step would be the combination of the terrestrial data with the data from our aerial photography. So far, the method works well and we

  3. 3D numerical modeling of India-Asia-like collision

    NASA Astrophysics Data System (ADS)

    -Erika Püsök, Adina; Kaus, Boris; Popov, Anton

    2013-04-01

    above a strong mantle lithosphere - the jelly sandwich model (Burov and Watts, 2006). 3D models are thus needed to investigate these hypotheses. However, fully 3D models of the dynamics of continent collision zones have only been developed very recently, and presently most research groups have relied on certain explicit assumptions for their codes. Here, we employ the parallel 3D code LaMEM (Lithosphere and Mantle Evolution Model), with a finite difference staggered grid solver, which is capable of simulating lithospheric deformation while simultaneously taking mantle flow and a free surface into account. We here report on first lithospheric and upper-mantle scale simulations in which the Indian lithosphere is indented into Asia. Acknowledgements. Funding was provided by the European Research Council under the European Community's Seventh Framework Program (FP7/2007-2013) / ERC Grant agreement #258830. Numerical computations have been performed on JUQUEEN of the Jülich high-performance computing center. • Beaumont, C., Jamieson, R.A., Nguyen, M.H., Medvedev, S.E., 2004. Crustal channel flows: 1. Numerical models with applications to the tectonics of the Himalayan-Tibetan orogeny. J. Geophys. Res. 109, B06406. • Burov, E. & Watts, W.S., 2006. The long-term strength of continental lithosphere: "jelly sandwich" or "crème brûlée"?. GSA Today, 16, doi: 10.1130/1052-5173(2006)1016<1134:TLTSOC>1132.1130.CO;1132. • England P., Houseman, G., 1986. Finite strain calculations of continental deformation. 2. Comparison with the India-Asia collision zone. J. Geophys. Res.- Solid Earth and Planets 91 (B3), 3664-3676. • Jackson, J., 2002. Strength of the continental lithosphere: time to abandon the jelly sandwich?. GSA Today, September, 4-10. • Lechmann, S.M., May, D.A., Kaus, B.J.P., Schmalholz, S.M., 2011. Comparing thin-sheet models with 3D multilayer models for continental collision. Geophy. Int. J. doi: 10.1111/j.1365-246X.2011.05164.x • Royden, L.H., Burchfiel, B

  4. 3D Printing of Molecular Potential Energy Surface Models

    ERIC Educational Resources Information Center

    Lolur, Phalgun; Dawes, Richard

    2014-01-01

    Additive manufacturing, commonly known as 3D printing, is gaining popularity in a variety of applications and has recently become routinely available. Today, 3D printing services are not only found in engineering design labs and through online companies, but also in university libraries offering student access. In addition, affordable options for…

  5. 3D-Digital soil property mapping by geoadditive models

    NASA Astrophysics Data System (ADS)

    Papritz, Andreas

    2016-04-01

    In many digital soil mapping (DSM) applications, soil properties must be predicted not only for a single but for multiple soil depth intervals. In the GlobalSoilMap project, as an example, predictions are computed for the 0-5 cm, 5-15 cm, 15-30 cm, 30-60 cm, 60-100 cm, 100-200 cm depth intervals (Arrouays et al., 2014). Legacy soil data are often used for DSM. It is common for such datasets that soil properties were measured for soil horizons or for layers at varying soil depth and with non-constant thickness (support). This poses problems for DSM: One strategy is to harmonize the soil data to common depth prior to the analyses (e.g. Bishop et al., 1999) and conduct the statistical analyses for each depth interval independently. The disadvantage of this approach is that the predictions for different depths are computed independently from each other so that the predicted depth profiles may be unrealistic. Furthermore, the error induced by the harmonization to common depth is ignored in this approach (Orton et al. 2016). A better strategy is therefore to process all soil data jointly without prior harmonization by a 3D-analysis that takes soil depth and geographical position explicitly into account. Usually, the non-constant support of the data is then ignored, but Orton et al. (2016) presented recently a geostatistical approach that accounts for non-constant support of soil data and relies on restricted maximum likelihood estimation (REML) of a linear geostatistical model with a separable, heteroscedastic, zonal anisotropic auto-covariance function and area-to-point kriging (Kyriakidis, 2004.) Although this model is theoretically coherent and elegant, estimating its many parameters by REML and selecting covariates for the spatial mean function is a formidable task. A simpler approach might be to use geoadditive models (Kammann and Wand, 2003; Wand, 2003) for 3D-analyses of soil data. geoAM extend the scope of the linear model with spatially correlated errors to

  6. The Input-Interface of Webcam Applied in 3D Virtual Reality Systems

    ERIC Educational Resources Information Center

    Sun, Huey-Min; Cheng, Wen-Lin

    2009-01-01

    Our research explores a virtual reality application based on Web camera (Webcam) input-interface. The interface can replace with the mouse to control direction intention of a user by the method of frame difference. We divide a frame into nine grids from Webcam and make use of the background registration to compute the moving object. In order to…

  7. Virtual Presence and the Mind's Eye in 3-D Online Communities

    NASA Astrophysics Data System (ADS)

    Beacham, R. C.; Denard, H.; Baker, D.

    2011-09-01

    Digital technologies have introduced fundamental changes in the forms, content, and media of communication. Indeed, some have suggested we are in the early stages of a seismic shift comparable to that in antiquity with the transition from a primarily oral culture to one based upon writing. The digital transformation is rapidly displacing the long-standing hegemony of text, and restoring in part social, bodily, oral and spatial elements, but in radically reconfigured forms and formats. Contributing to and drawing upon such changes and possibilities, scholars and those responsible for sites preserving or displaying cultural heritage, have undertaken projects to explore the properties and potential of the online communities enabled by "Virtual Worlds" and related platforms for teaching, collaboration, publication, and new modes of disciplinary research. Others, keenly observing and evaluating such work, are poised to contribute to it. It is crucial that leadership be provided to ensure that serious and sustained investigation be undertaken by scholars who have experience, and achievements, in more traditional forms of research, and who perceive the emerging potential of Virtual World work to advance their investigations. The Virtual Museums Transnational Network will seek to engage such scholars and provide leadership in this emerging and immensely attractive new area of cultural heritage exploration and experience. This presentation reviews examples of the current "state of the art" in heritage based Virtual World initiatives, looking at the new modes of social interaction and experience enabled by such online communities, and some of the achievements and future aspirations of this work.

  8. "The Evolution of e-Learning in the Context of 3D Virtual Worlds"

    ERIC Educational Resources Information Center

    Kotsilieris, Theodore; Dimopoulou, Nikoletta

    2013-01-01

    Information and Communication Technologies (ICT) offer new approaches towards knowledge acquisition and collaboration through distance learning processes. Web-based Learning Management Systems (LMS) have transformed the way that education is conducted nowadays. At the same time, the adoption of Virtual Worlds in the educational process is of great…

  9. Collaboration and Knowledge Sharing Using 3D Virtual World on "Second Life"

    ERIC Educational Resources Information Center

    Rahim, Noor Faridah A.

    2013-01-01

    A collaborative and knowledge sharing virtual activity on "Second Life" using a learner-centred teaching methodology was initiated between Temasek Polytechnic and The Hong Kong Polytechnic University (HK PolyU) in the October 2011 semester. This paper highlights the author's experience in designing and implementing this e-learning…

  10. 3D shape modeling by integration visual and tactile cues

    NASA Astrophysics Data System (ADS)

    Xiong, Hanwei; Xu, Jun; Xu, Chenxi; Pan, Ming

    2015-10-01

    With the progress in CAD (Computer Aided Design) systems, many mechanical components can be designed efficiently with high precision. But, such a system is unfit for some organic shapes, for example, a toy. In this paper, an easy way to dealing with such shapes is presented, combing visual perception with tangible interaction. The method is divided into three phases: two tangible interaction phases and one visual reconstruction. In the first tangible phase, a clay model is used to represent the raw shape, and the designer can change the shape intuitively with his hands. Then the raw shape is scanned into a digital volume model through a low cost vision system. In the last tangible phase, a desktop haptic device from SensAble is used to refine the scanned volume model and convert it into a surface model. A physical clay model and a virtual clay mode are all used in this method to deal with the main shape and the details respectively, and the vision system is used to bridge the two tangible phases. The vision reconstruction system is only made of a camera to acquire raw shape through shape from silhouettes method. All of the systems are installed on a single desktop, make it convenient for designers. The vision system details and a design example are presented in the papers.

  11. 3D-Digital soil property mapping by geoadditive models

    NASA Astrophysics Data System (ADS)

    Papritz, Andreas

    2016-04-01

    In many digital soil mapping (DSM) applications, soil properties must be predicted not only for a single but for multiple soil depth intervals. In the GlobalSoilMap project, as an example, predictions are computed for the 0-5 cm, 5-15 cm, 15-30 cm, 30-60 cm, 60-100 cm, 100-200 cm depth intervals (Arrouays et al., 2014). Legacy soil data are often used for DSM. It is common for such datasets that soil properties were measured for soil horizons or for layers at varying soil depth and with non-constant thickness (support). This poses problems for DSM: One strategy is to harmonize the soil data to common depth prior to the analyses (e.g. Bishop et al., 1999) and conduct the statistical analyses for each depth interval independently. The disadvantage of this approach is that the predictions for different depths are computed independently from each other so that the predicted depth profiles may be unrealistic. Furthermore, the error induced by the harmonization to common depth is ignored in this approach (Orton et al. 2016). A better strategy is therefore to process all soil data jointly without prior harmonization by a 3D-analysis that takes soil depth and geographical position explicitly into account. Usually, the non-constant support of the data is then ignored, but Orton et al. (2016) presented recently a geostatistical approach that accounts for non-constant support of soil data and relies on restricted maximum likelihood estimation (REML) of a linear geostatistical model with a separable, heteroscedastic, zonal anisotropic auto-covariance function and area-to-point kriging (Kyriakidis, 2004.) Although this model is theoretically coherent and elegant, estimating its many parameters by REML and selecting covariates for the spatial mean function is a formidable task. A simpler approach might be to use geoadditive models (Kammann and Wand, 2003; Wand, 2003) for 3D-analyses of soil data. geoAM extend the scope of the linear model with spatially correlated errors to

  12. Towards a Transcription System of Sign Language for 3D Virtual Agents

    NASA Astrophysics Data System (ADS)

    Do Amaral, Wanessa Machado; de Martino, José Mario

    Accessibility is a growing concern in computer science. Since virtual information is mostly presented visually, it may seem that access for deaf people is not an issue. However, for prelingually deaf individuals, those who were deaf since before acquiring and formally learn a language, written information is often of limited accessibility than if presented in signing. Further, for this community, signing is their language of choice, and reading text in a spoken language is akin to using a foreign language. Sign language uses gestures and facial expressions and is widely used by deaf communities. To enabling efficient production of signed content on virtual environment, it is necessary to make written records of signs. Transcription systems have been developed to describe sign languages in written form, but these systems have limitations. Since they were not originally designed with computer animation in mind, in general, the recognition and reproduction of signs in these systems is an easy task only to those who deeply know the system. The aim of this work is to develop a transcription system to provide signed content in virtual environment. To animate a virtual avatar, a transcription system requires explicit enough information, such as movement speed, signs concatenation, sequence of each hold-and-movement and facial expressions, trying to articulate close to reality. Although many important studies in sign languages have been published, the transcription problem remains a challenge. Thus, a notation to describe, store and play signed content in virtual environments offers a multidisciplinary study and research tool, which may help linguistic studies to understand the sign languages structure and grammar.

  13. Virtual touch 3D interactive system for autostereoscopic display with embedded optical sensor

    NASA Astrophysics Data System (ADS)

    Huang, Yi-Pai; Wang, Guo-Zhen; Ma, Ming-Ching; Tung, Shang-Yu; Huang, Shu-Yi; Tseng, Hung-Wei; Kuo, Chung-Hong; Li, Chun-Huai

    2011-06-01

    The traidational 3D interactive sysetm which uses CCD camera to capture image is difficult to operate on near range for mobile applications.Therefore, 3D interactive display with embedded optical sensor was proposed. Based on optical sensor based system, we proposed four different methods to support differenct functions. T mark algorithm can obtain 5- axis information (x, y, z,θ, and φ)of LED no matter where LED was vertical or inclined to panel and whatever it rotated. Sequential mark algorithm and color filter based algorithm can support mulit-user. Finally, bare finger touch system with sequential illuminator can achieve to interact with auto-stereoscopic images by bare finger. Furthermore, the proposed methods were verified on a 4-inch panel with embedded optical sensors.

  14. 3D Finite Difference Modelling of Basaltic Region

    NASA Astrophysics Data System (ADS)

    Engell-Sørensen, L.

    2003-04-01

    The main purpose of the work was to generate realistic data to be applied for testing of processing and migration tools for basaltic regions. The project is based on the three - dimensional finite difference code (FD), TIGER, made by Sintef. The FD code was optimized (parallelized) by the author, to run on parallel computers. The parallel code enables us to model large-scale realistic geological models and to apply traditional seismic and micro seismic sources. The parallel code uses multiple processors in order to manipulate subsets of large amounts of data simultaneously. The general anisotropic code uses 21 elastic coefficients. Eight independent coefficients are needed as input parameters for the general TI medium. In the FD code, the elastic wave field computation is implemented by a higher order FD solution to the elastic wave equation and the wave fields are computed on a staggered grid, shifted half a node in one or two directions. The geological model is a gridded basalt model, which covers from 24 km to 37 km of a real shot line in horizontal direction and from the water surface to the depth of 3.5 km. The 2frac {1}{2}D model has been constructed using the compound modeling software from Norsk Hydro. The vertical parameter distribution is obtained from observations in two wells. At The depth of between 1100 m to 1500 m, a basalt horizon covers the whole sub surface layers. We have shown that it is possible to simulate a line survey in realistic (3D) geological models in reasonable time by using high performance computers. The author would like to thank Norsk Hydro, Statoil, GEUS, and SINTEF for very helpful discussions and Parallab for being helpful with the new IBM, p690 Regatta system.

  15. Predicted 3D Model of the Rabies Virus Glycoprotein Trimer.

    PubMed

    Fernando, Bastida-González; Yersin, Celaya-Trejo; José, Correa-Basurto; Paola, Zárate-Segura

    2016-01-01

    The RABVG ectodomain is a homotrimer, and trimers are often called spikes. They are responsible for the attachment of the virus through the interaction with nicotinic acetylcholine receptors, neural cell adhesion molecule (NCAM), and the p75 neurotrophin receptor (p75NTR). This makes them relevant in viral pathogenesis. The antigenic structure differs significantly between the trimers and monomers. Surfaces rich in hydrophobic amino acids are important for trimer stabilization in which the C-terminal of the ectodomain plays an important role; to understand these interactions between the G proteins, a mechanistic study of their functions was performed with a molecular model of G protein in its trimeric form. This verified its 3D conformation. The molecular modeling of G protein was performed by a I-TASSER server and was evaluated via a Rachamandran plot and ERRAT program obtained 84.64% and 89.9% of the residues in the favorable regions and overall quality factor, respectively. The molecular dynamics simulations were carried out on RABVG trimer at 310 K. From these theoretical studies, we retrieved the RMSD values from Cα atoms to assess stability. Preliminary model of G protein of rabies virus stable at 12 ns with molecular dynamics was obtained. PMID:27294109

  16. Predicted 3D Model of the Rabies Virus Glycoprotein Trimer

    PubMed Central

    Fernando, Bastida-González; Yersin, Celaya-Trejo; José, Correa-Basurto; Paola, Zárate-Segura

    2016-01-01

    The RABVG ectodomain is a homotrimer, and trimers are often called spikes. They are responsible for the attachment of the virus through the interaction with nicotinic acetylcholine receptors, neural cell adhesion molecule (NCAM), and the p75 neurotrophin receptor (p75NTR). This makes them relevant in viral pathogenesis. The antigenic structure differs significantly between the trimers and monomers. Surfaces rich in hydrophobic amino acids are important for trimer stabilization in which the C-terminal of the ectodomain plays an important role; to understand these interactions between the G proteins, a mechanistic study of their functions was performed with a molecular model of G protein in its trimeric form. This verified its 3D conformation. The molecular modeling of G protein was performed by a I-TASSER server and was evaluated via a Rachamandran plot and ERRAT program obtained 84.64% and 89.9% of the residues in the favorable regions and overall quality factor, respectively. The molecular dynamics simulations were carried out on RABVG trimer at 310 K. From these theoretical studies, we retrieved the RMSD values from Cα atoms to assess stability. Preliminary model of G protein of rabies virus stable at 12 ns with molecular dynamics was obtained. PMID:27294109

  17. Collision of continental corner from 3-D numerical modeling

    NASA Astrophysics Data System (ADS)

    Li, Zhong-Hai; Xu, Zhiqin; Gerya, Taras; Burg, Jean-Pierre

    2013-10-01

    Continental collision has been extensively investigated with 2-D numerical models assuming infinitely wide plates or insignificant along-strike deformation in the third dimension. However, the corners of natural collision zones normally have structural characteristics that differ from linear parts of mountain belt. We conducted 3-D high-resolution numerical simulations to study the dynamics of a continental corner (lateral continental/oceanic transition zone) during subduction/collision. The results demonstrate different modes between the oceanic subduction side (continuous subduction and retreating trench) and the continental collision side (slab break-off and topography uplift). Slab break-off occurs at a depth (⩽100 km to ˜300 km) that depends on the convergence velocity. The numerical models produce lateral extrusion of the overriding crust from the collisional side to the subduction side, which is also a phenomenon recognized around natural collision of continental corners, for instance around the western corner of the Arabia-Asia collision zone and around the eastern corner of the India-Asia collision zone. Modeling results also indicate that extrusion tectonics may be driven both from above by the topography and gravitational potentials and from below by the trench retreat and asthenospheric mantle return flow, which supports the link between deep mantle dynamics a