Science.gov

Sample records for 3-d computer graphics

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

    ERIC Educational Resources Information Center

    Matsuda, Hiroshi; Shindo, Yoshiaki

    2006-01-01

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

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

    ERIC Educational Resources Information Center

    Matsuda, Hiroshi; Shindo, Yoshiaki

    2006-01-01

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

  3. Implementation Of True 3D Cursors In Computer Graphics

    NASA Astrophysics Data System (ADS)

    Butts, David R.; McAllister, David F.

    1988-06-01

    The advances in stereoscopic image display techniques have shown an increased need for real-time interaction with the three-dimensional image. We have developed a prototype real-time stereoscopic cursor to investigate this interaction. The results have pointed out areas where hardware speeds are a limiting factor, as well as areas where various methodologies cause perceptual difficulties. This paper addresses the psychological and perceptual anomalies involved in stereo image techniques, cursor generation and motion, and the use of the device as a 3D drawing and depth measuring tool.

  4. Using 3D Computer Graphics Multimedia to Motivate Preservice Teachers' Learning of Geometry and Pedagogy

    ERIC Educational Resources Information Center

    Goodson-Espy, Tracy; Lynch-Davis, Kathleen; Schram, Pamela; Quickenton, Art

    2010-01-01

    This paper describes the genesis and purpose of our geometry methods course, focusing on a geometry-teaching technology we created using NVIDIA[R] Chameleon demonstration. This article presents examples from a sequence of lessons centered about a 3D computer graphics demonstration of the chameleon and its geometry. In addition, we present data…

  5. 3D object optonumerical acquisition methods for CAD/CAM and computer graphics systems

    NASA Astrophysics Data System (ADS)

    Sitnik, Robert; Kujawinska, Malgorzata; Pawlowski, Michal E.; Woznicki, Jerzy M.

    1999-08-01

    The creation of a virtual object for CAD/CAM and computer graphics on the base of data gathered by full-field optical measurement of 3D object is presented. The experimental co- ordinates are alternatively obtained by combined fringe projection/photogrammetry based system or fringe projection/virtual markers setup. The new and fully automatic procedure which process the cloud of measured points into triangular mesh accepted by CAD/CAM and computer graphics systems is presented. Its applicability for various classes of objects is tested including the error analysis of virtual objects generated. The usefulness of the method is proved by applying the virtual object in rapid prototyping system and in computer graphics environment.

  6. Interactive virtual simulation using a 3D computer graphics model for microvascular decompression surgery.

    PubMed

    Oishi, Makoto; Fukuda, Masafumi; Hiraishi, Tetsuya; Yajima, Naoki; Sato, Yosuke; Fujii, Yukihiko

    2012-09-01

    The purpose of this paper is to report on the authors' advanced presurgical interactive virtual simulation technique using a 3D computer graphics model for microvascular decompression (MVD) surgery. The authors performed interactive virtual simulation prior to surgery in 26 patients with trigeminal neuralgia or hemifacial spasm. The 3D computer graphics models for interactive virtual simulation were composed of the brainstem, cerebellum, cranial nerves, vessels, and skull individually created by the image analysis, including segmentation, surface rendering, and data fusion for data collected by 3-T MRI and 64-row multidetector CT systems. Interactive virtual simulation was performed by employing novel computer-aided design software with manipulation of a haptic device to imitate the surgical procedures of bone drilling and retraction of the cerebellum. The findings were compared with intraoperative findings. In all patients, interactive virtual simulation provided detailed and realistic surgical perspectives, of sufficient quality, representing the lateral suboccipital route. The causes of trigeminal neuralgia or hemifacial spasm determined by observing 3D computer graphics models were concordant with those identified intraoperatively in 25 (96%) of 26 patients, which was a significantly higher rate than the 73% concordance rate (concordance in 19 of 26 patients) obtained by review of 2D images only (p < 0.05). Surgeons evaluated interactive virtual simulation as having "prominent" utility for carrying out the entire surgical procedure in 50% of cases. It was evaluated as moderately useful or "supportive" in the other 50% of cases. There were no cases in which it was evaluated as having no utility. The utilities of interactive virtual simulation were associated with atypical or complex forms of neurovascular compression and structural restrictions in the surgical window. Finally, MVD procedures were performed as simulated in 23 (88%) of the 26 patients . Our

  7. Tensor3D: A computer graphics program to simulate 3D real-time deformation and visualization of geometric bodies

    NASA Astrophysics Data System (ADS)

    Pallozzi Lavorante, Luca; Dirk Ebert, Hans

    2008-07-01

    Tensor3D is a geometric modeling program with the capacity to simulate and visualize in real-time the deformation, specified through a tensor matrix and applied to triangulated models representing geological bodies. 3D visualization allows the study of deformational processes that are traditionally conducted in 2D, such as simple and pure shears. Besides geometric objects that are immediately available in the program window, the program can read other models from disk, thus being able to import objects created with different open-source or proprietary programs. A strain ellipsoid and a bounding box are simultaneously shown and instantly deformed with the main object. The principal axes of strain are visualized as well to provide graphical information about the orientation of the tensor's normal components. The deformed models can also be saved, retrieved later and deformed again, in order to study different steps of progressive strain, or to make this data available to other programs. The shape of stress ellipsoids and the corresponding Mohr circles defined by any stress tensor can also be represented. The application was written using the Visualization ToolKit, a powerful scientific visualization library in the public domain. This development choice, allied to the use of the Tcl/Tk programming language, which is independent on the host computational platform, makes the program a useful tool for the study of geometric deformations directly in three dimensions in teaching as well as research activities.

  8. The effects of 3D interactive animated graphics on student learning and attitudes in computer-based instruction

    NASA Astrophysics Data System (ADS)

    Moon, Hye Sun

    Visuals are most extensively used as instructional tools in education to present spatially-based information. Recent computer technology allows the generation of 3D animated visuals to extend the presentation in computer-based instruction. Animated visuals in 3D representation not only possess motivational value that promotes positive attitudes toward instruction but also facilitate learning when the subject matter requires dynamic motion and 3D visual cue. In this study, three questions are explored: (1) how 3D graphics affects student learning and attitude, in comparison with 2D graphics; (2) how animated graphics affects student learning and attitude, in comparison with static graphics; and (3) whether the use of 3D graphics, when they are supported by interactive animation, is the most effective visual cues to improve learning and to develop positive attitudes. A total of 145 eighth-grade students participated in a 2 x 2 factorial design study. The subjects were randomly assigned to one of four computer-based instructions: 2D static; 2D animated; 3D static; and 3D animated. The results indicated that: (1) Students in the 3D graphic condition exhibited more positive attitudes toward instruction than those in the 2D graphic condition. No group differences were found between the posttest score of 3D graphic condition and that of 2D graphic condition. However, students in the 3D graphic condition took less time for information retrieval on posttest than those in the 2D graphic condition. (2) Students in the animated graphic condition exhibited slightly more positive attitudes toward instruction than those in the static graphic condition. No group differences were found between the posttest score of animated graphic condition and that of static graphic condition. However, students in the animated graphic condition took less time for information retrieval on posttest than those in the static graphic condition. (3) Students in the 3D animated graphic condition

  9. A Microscopic Optically Tracking Navigation System That Uses High-resolution 3D Computer Graphics.

    PubMed

    Yoshino, Masanori; Saito, Toki; Kin, Taichi; Nakagawa, Daichi; Nakatomi, Hirofumi; Oyama, Hiroshi; Saito, Nobuhito

    2015-01-01

    Three-dimensional (3D) computer graphics (CG) are useful for preoperative planning of neurosurgical operations. However, application of 3D CG to intraoperative navigation is not widespread because existing commercial operative navigation systems do not show 3D CG in sufficient detail. We have developed a microscopic optically tracking navigation system that uses high-resolution 3D CG. This article presents the technical details of our microscopic optically tracking navigation system. Our navigation system consists of three components: the operative microscope, registration, and the image display system. An optical tracker was attached to the microscope to monitor the position and attitude of the microscope in real time; point-pair registration was used to register the operation room coordinate system, and the image coordinate system; and the image display system showed the 3D CG image in the field-of-view of the microscope. Ten neurosurgeons (seven males, two females; mean age 32.9 years) participated in an experiment to assess the accuracy of this system using a phantom model. Accuracy of our system was compared with the commercial system. The 3D CG provided by the navigation system coincided well with the operative scene under the microscope. Target registration error for our system was 2.9 ± 1.9 mm. Our navigation system provides a clear image of the operation position and the surrounding structures. Systems like this may reduce intraoperative complications.

  10. A Microscopic Optically Tracking Navigation System That Uses High-resolution 3D Computer Graphics

    PubMed Central

    YOSHINO, Masanori; SAITO, Toki; KIN, Taichi; NAKAGAWA, Daichi; NAKATOMI, Hirofumi; OYAMA, Hiroshi; SAITO, Nobuhito

    2015-01-01

    Three-dimensional (3D) computer graphics (CG) are useful for preoperative planning of neurosurgical operations. However, application of 3D CG to intraoperative navigation is not widespread because existing commercial operative navigation systems do not show 3D CG in sufficient detail. We have developed a microscopic optically tracking navigation system that uses high-resolution 3D CG. This article presents the technical details of our microscopic optically tracking navigation system. Our navigation system consists of three components: the operative microscope, registration, and the image display system. An optical tracker was attached to the microscope to monitor the position and attitude of the microscope in real time; point-pair registration was used to register the operation room coordinate system, and the image coordinate system; and the image display system showed the 3D CG image in the field-of-view of the microscope. Ten neurosurgeons (seven males, two females; mean age 32.9 years) participated in an experiment to assess the accuracy of this system using a phantom model. Accuracy of our system was compared with the commercial system. The 3D CG provided by the navigation system coincided well with the operative scene under the microscope. Target registration error for our system was 2.9 ± 1.9 mm. Our navigation system provides a clear image of the operation position and the surrounding structures. Systems like this may reduce intraoperative complications. PMID:26226982

  11. 3D animation of facial plastic surgery based on computer graphics

    NASA Astrophysics Data System (ADS)

    Zhang, Zonghua; Zhao, Yan

    2013-12-01

    More and more people, especial women, are getting desired to be more beautiful than ever. To some extent, it becomes true because the plastic surgery of face was capable in the early 20th and even earlier as doctors just dealing with war injures of face. However, the effect of post-operation is not always satisfying since no animation could be seen by the patients beforehand. In this paper, by combining plastic surgery of face and computer graphics, a novel method of simulated appearance of post-operation will be given to demonstrate the modified face from different viewpoints. The 3D human face data are obtained by using 3D fringe pattern imaging systems and CT imaging systems and then converted into STL (STereo Lithography) file format. STL file is made up of small 3D triangular primitives. The triangular mesh can be reconstructed by using hash function. Top triangular meshes in depth out of numbers of triangles must be picked up by ray-casting technique. Mesh deformation is based on the front triangular mesh in the process of simulation, which deforms interest area instead of control points. Experiments on face model show that the proposed 3D animation facial plastic surgery can effectively demonstrate the simulated appearance of post-operation.

  12. Application of 3-D computer graphics for facial reconstruction and comparison with sculpting techniques.

    PubMed

    Vanezis, P; Blowes, R W; Linney, A D; Tan, A C; Richards, R; Neave, R

    1989-07-01

    Facial reconstruction has until now been carried out by the sculpting technique. This method involves building a face with clay or other suitable material on to a skull or its cast, taking into account appropriate facial thickness measurements together with information provided by anthropologists such as approximate age, sex, race and other individual idiosyncrasies. A method for facial reconstruction is presented using 3-D computer graphics and is compared with the manual technique. The computer method involves initially digitising a skull using a laser scanner and video camera interfaced to a computer. A face, from a data bank which has previously digitised facial surfaces, is then placed over the skull in the form of a mask and the skin thickness is altered to conform with the underlying skull. The advantage of the computer method is its speed and flexibility. We have shown that the computer method for reconstructing a face is feasible and furthermore has the advantage over the manual technique of speed and flexibility. Nevertheless, the technique is far from perfect. Further facial thickness data needs collecting and the method requires evaluation using both known control skulls and later unknown remains.

  13. Dynamic 3-D computer graphics for designing a diagnostic tool for patients with schizophrenia.

    PubMed

    Farkas, Attila; Papathomas, Thomas V; Silverstein, Steven M; Kourtev, Hristiyan; Papayanopoulos, John F

    2016-11-01

    We introduce a novel procedure that uses dynamic 3-D computer graphics as a diagnostic tool for assessing disease severity in schizophrenia patients, based on their reduced influence of top-down cognitive processes in interpreting bottom-up sensory input. Our procedure uses the hollow-mask illusion, in which the concave side of the mask is misperceived as convex, because familiarity with convex faces dominates sensory cues signaling a concave mask. It is known that schizophrenia patients resist this illusion and their resistance increases with illness severity. Our method uses virtual masks rendered with two competing textures: (a) realistic features that enhance the illusion; (b) random-dot visual noise that reduces the illusion. We control the relative weights of the two textures to obtain psychometric functions for controls and patients and assess illness severity. The primary novelty is the use of a rotating mask that is easy to implement on a wide variety of portable devices and avoids the use of elaborate stereoscopic devices that have been used in the past. Thus our method, which can also be used to assess the efficacy of treatments, provides clinicians the advantage to bring the test to the patient's own environment, instead of having to bring patients to the clinic.

  14. High-Performance Active Liquid Crystalline Shutters for Stereo Computer Graphics and Other 3-D Technologies

    NASA Astrophysics Data System (ADS)

    Sergan, Tatiana; Sergan, Vassili; MacNaughton, Boyd

    2007-03-01

    Stereoscopic computer displays create a 3-D image by alternating two separate images for each of the viewer's eyes. Field-sequential viewing systems supply each eye with the appropriate image by blocking the wrong image for the wrong eye. In our work, we have developed a new mode of operation of a liquid crystal shutter that provides for highly effective blockage of undesired images when the screen is viewed in all viewing directions and eliminates color shifts associated with long turn-off times. The goal was achieved by using a π-cell filled with low-rotational-viscosity and high-birefringence fluid and additional negative birefringence films with splay optic axis distribution. The shutter demonstrates a contrast ratio higher than 800:1 for head-on viewing and 10:1 in the viewing cone of about 45°. The relaxation time of the shutter does not exceed 2 ms and is the same for all three primary colors.

  15. 3D Computer graphics simulation to obtain optimal surgical exposure during microvascular decompression of the glossopharyngeal nerve.

    PubMed

    Hiraishi, Tetsuya; Matsushima, Toshio; Kawashima, Masatou; Nakahara, Yukiko; Takahashi, Yuichi; Ito, Hiroshi; Oishi, Makoto; Fujii, Yukihiko

    2013-10-01

    The affected artery in glossopharyngeal neuralgia (GPN) is most often the posterior inferior cerebellar artery (PICA) from the caudal side or the anterior inferior cerebellar artery (AICA) from the rostral side. This technical report describes two representative cases of GPN, one with PICA as the affected artery and the other with AICA, and demonstrates the optimal approach for each affected artery. We used 3D computer graphics (3D CG) simulation to consider the ideal transposition of the affected artery in any position and approach. Subsequently, we performed microvascular decompression (MVD) surgery based on this simulation. For PICA, we used the transcondylar fossa approach in the lateral recumbent position, very close to the prone position, with the patient's head tilted anteriorly for caudal transposition of PICA. In contrast, for AICA, we adopted a lateral suboccipital approach with opening of the lateral cerebellomedullary fissure, to visualize better the root entry zone of the glossopharyngeal nerve and to obtain a wide working space in the cerebellomedullary cistern, for rostral transposition of AICA. Both procedures were performed successfully. The best surgical approach for MVD in patients with GPN is contingent on the affected artery--PICA or AICA. 3D CG simulation provides tailored approach for MVD of the glossopharyngeal nerve, thereby ensuring optimal surgical exposure.

  16. Isoparametric 3-D Finite Element Mesh Generation Using Interactive Computer Graphics

    NASA Technical Reports Server (NTRS)

    Kayrak, C.; Ozsoy, T.

    1985-01-01

    An isoparametric 3-D finite element mesh generator was developed with direct interface to an interactive geometric modeler program called POLYGON. POLYGON defines the model geometry in terms of boundaries and mesh regions for the mesh generator. The mesh generator controls the mesh flow through the 2-dimensional spans of regions by using the topological data and defines the connectivity between regions. The program is menu driven and the user has a control of element density and biasing through the spans and can also apply boundary conditions, loads interactively.

  17. Microvision system (MVS): a 3D computer graphic-based microrobot telemanipulation and position feedback by vision

    NASA Astrophysics Data System (ADS)

    Sulzmann, Armin; Breguet, Jean-Marc; Jacot, Jacques

    1995-12-01

    The aim of our project is to control the position in 3D-space of a micro robot with sub micron accuracy and manipulate Microsystems aided by a real time 3D computer graphics (virtual reality). As Microsystems and micro structures become smaller, it is necessary to build a micro robot ((mu) -robot) capable of manipulating these systems and structures with a precision of 1 micrometers or even higher. These movements have to be controlled and guided. The first part of our project was to develop a real time 3D computer graphics (virtual reality) environment man-machine interface to guide the newly developed robot similar to the environment we built in a macroscopic robotics. Secondly we want to evaluate measurement techniques to verify its position in the region of interest (workspace). A new type of microrobot has been developed for our purposed. Its simple and compact design is believed to be of promise in the microrobotics field. Stepping motion allows speed up to 4 mm/s. Resolution smaller than 10 nm is achievable. We also focus on the vision system and on the virtual reality interface of the complex system. Basically the user interacts with the virtual 3D microscope and sees the (mu) -robot as if he is looking through a real microscope. He is able to simulate the assembly of the missing parts, e.g. parts of the micrometer, beforehand in order to verify the assembly manipulation steps such assembly of the missing parts, e.g. parts of a micromotor, beforehand in order to verify the assembly manipulation steps such as measuring, moving the table to the right position or performing the manipulation. Micro manipulation is form of a teleoperation is then performed by the robot-unit and the position is controlled by vision. First results have shown, that a guided manipulations with submicronics absolute accuracy can be achieved. Key idea of this approach is to use the intuitiveness of immersed vision to perform robotics tasks in an environment where human has only access

  18. A new method for combining live action and computer graphics in stereoscopic 3D

    NASA Astrophysics Data System (ADS)

    Rupkalvis, John A.; Gillen, Ron

    2008-02-01

    A primary requirement when elements are to be combined stereoscopically, is that homologous points in each eye view of each element have identical parallax separation at any point of interaction. If this is not done, the image parts on one element will appear to be at a different distance from the corresponding or associated parts on the other element. This results in a visual discontinuity that appears very unnatural. For example, if a live actor were to appear to "shake hands" with a cartoon character, a very natural appearing juncture may appear to be the case when seen in 2-D, but their hands may appear to miss when seen in 3-D. Previous efforts to compensate, or correct these errors have involved painstaking time-consuming trial-and-error tests. In the area of pure animation, efforts to make cartoon characters appear more realistic were developed. A "motion tracking" technique was developed. This involves an actor wearing a special suit with indicator marks at various points on their body. The actor walks through the scene, then the animator tracks the points using motion capture software. Because live action and CG elements can interact or change at several different points and levels within a scene, additional requirements must also be addressed. "Occlusions" occur when one object passes in front of another. A particular tracking point may appear in one eye-view, and not the other. When Z-axis differentials are to be considered in the live action as well as the CG elements, and both are to interact with each other, both eye-views must be tracked, especially at points of occlusion. A new approach would be to generate a three dimensional grid, within which the action is to take place. This grid can be projected, onto the stage where the live action part is to take place. When differential occlusions occur, the grid may be seen and CG elements plotted in reference to it. Because of the capability of precisely locating points in a digital image, a pixel

  19. Computer Graphics.

    ERIC Educational Resources Information Center

    Halpern, Jeanne W.

    1970-01-01

    Computer graphics have been called the most exciting development in computer technology. At the University of Michigan, three kinds of graphics output equipment are now being used: symbolic printers, line plotters or drafting devices, and cathode-ray tubes (CRT). Six examples are given that demonstrate the range of graphics use at the University.…

  20. 3D Graphics Through the Internet: A "Shoot-Out"

    NASA Technical Reports Server (NTRS)

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

    1995-01-01

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

  1. 3D Graphics Through the Internet: A "Shoot-Out"

    NASA Technical Reports Server (NTRS)

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

    1995-01-01

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

  2. Introduction to 3D Graphics through Excel

    ERIC Educational Resources Information Center

    Benacka, Jan

    2013-01-01

    The article presents a method of explaining the principles of 3D graphics through making a revolvable and sizable orthographic parallel projection of cuboid in Excel. No programming is used. The method was tried in fourteen 90 minute lessons with 181 participants, which were Informatics teachers, undergraduates of Applied Informatics and gymnasium…

  3. Programmer's Guide for Subroutine PRNT3D. Physical Processes in Terrestrial and Aquatic Ecosystems, Computer Programs and Graphics Capabilities.

    ERIC Educational Resources Information Center

    Gales, Larry

    These materials were designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. PRNT3D is a subroutine package which generates a variety of printed plot displays. The displays…

  4. User's Guide for Subroutine PLOT3D. Physical Processes in Terrestrial and Aquatic Ecosystems, Computer Programs and Graphics Capabilities.

    ERIC Educational Resources Information Center

    Gales, Larry

    This module is part of a series designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. PLOT3D is a subroutine package which generates a variety of three dimensional hidden…

  5. Programmer's Guide for Subroutine PLOT3D. Physical Processes in Terrestrial and Aquatic Ecosystems, Computer Programs and Graphics Capabilities.

    ERIC Educational Resources Information Center

    Gales, Larry

    This module is part of a series designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. PLOT3D is a subroutine package which generates a variety of three-dimensional hidden…

  6. User's Guide for Subroutine PRNT3D. Physical Processes in Terrestrial and Aquatic Ecosystems, Computer Programs and Graphics Capabilities.

    ERIC Educational Resources Information Center

    Gales, Larry

    These materials were designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. PRNT3D is a subroutine package which generates a variety of printer plot displays. The displays…

  7. Computer Graphics Meets Image Fusion: the Power of Texture Baking to Simultaneously Visualise 3d Surface Features and Colour

    NASA Astrophysics Data System (ADS)

    Verhoeven, G. J.

    2017-08-01

    Since a few years, structure-from-motion and multi-view stereo pipelines have become omnipresent in the cultural heritage domain. The fact that such Image-Based Modelling (IBM) approaches are capable of providing a photo-realistic texture along the threedimensional (3D) digital surface geometry is often considered a unique selling point, certainly for those cases that aim for a visually pleasing result. However, this texture can very often also obscure the underlying geometrical details of the surface, making it very hard to assess the morphological features of the digitised artefact or scene. Instead of constantly switching between the textured and untextured version of the 3D surface model, this paper presents a new method to generate a morphology-enhanced colour texture for the 3D polymesh. The presented approach tries to overcome this switching between objects visualisations by fusing the original colour texture data with a specific depiction of the surface normals. Whether applied to the original 3D surface model or a lowresolution derivative, this newly generated texture does not solely convey the colours in a proper way but also enhances the smalland large-scale spatial and morphological features that are hard or impossible to perceive in the original textured model. In addition, the technique is very useful for low-end 3D viewers, since no additional memory and computing capacity are needed to convey relief details properly. Apart from simple visualisation purposes, the textured 3D models are now also better suited for on-surface interpretative mapping and the generation of line drawings.

  8. Natural frequencies and mode shapes of an automotive tire with interpretation and classification using 3-D computer graphics

    NASA Astrophysics Data System (ADS)

    Kung, L. E.; Soedel, W.; Yang, T. Y.; Charek, L. T.

    1985-10-01

    Natural frequencies and mode shapes of a radial tire have been obtained by using an efficient, 12 degree of freedom, doubly curved thin shell finite element of revolution with smeared-out properties of laminate composite materials. The finite element formulation includes the geometrical non-linearities so that the prestressed state of the tire due to inflation is taken into account. While the basic formulation follows that of earlier work done at Purdue University, a general and efficient computational procedure and program have been developed, with a main feature being integration with computer graphics. Thus the complex tire geometry can be modeled more accurately and the free vibration mode shapes can be displayed graphically. This allows an interpretation and classification of mode shapes beyond the classical mode shapes of tires that have been presented in the literature. It allows further insight into the relationship between transverse and tangential motions beyond what has been conceived at the present state of the art of experimentation. Theoretical results are compared with experimental results obtained from modal analysis and good agreement is shown.

  9. Postprocessing of compressed 3D graphic data by using subdivision

    NASA Astrophysics Data System (ADS)

    Cheang, Ka Man; Li, Jiankun; Kuo, C.-C. Jay

    1998-10-01

    In this work, we present a postprocessing technique applied to a 3D graphic model of a lower resolution to obtain a visually more pleasant representation. Our method is an improved version of the Butterfly subdivision scheme developed by Zorin et al. Our main contribution is to exploit the flatness information of local areas of a 3D graphic model for adaptive refinement. Consequently, we can avoid unnecessary subdivision in regions which are relatively flat. The proposed new algorithm not only reduces the computational complexity but also saves the storage space. With the hierarchical mesh compression method developed by Li and Kuo as the baseline coding method, we show that the postprocessing technique can greatly improve the visual quality of the decoded 3D graphic model.

  10. The Digital Space Shuttle, 3D Graphics, and Knowledge Management

    NASA Technical Reports Server (NTRS)

    Gomez, Julian E.; Keller, Paul J.

    2003-01-01

    The Digital Shuttle is a knowledge management project that seeks to define symbiotic relationships between 3D graphics and formal knowledge representations (ontologies). 3D graphics provides geometric and visual content, in 2D and 3D CAD forms, and the capability to display systems knowledge. Because the data is so heterogeneous, and the interrelated data structures are complex, 3D graphics combined with ontologies provides mechanisms for navigating the data and visualizing relationships.

  11. The Digital Space Shuttle, 3D Graphics, and Knowledge Management

    NASA Technical Reports Server (NTRS)

    Gomez, Julian E.; Keller, Paul J.

    2003-01-01

    The Digital Shuttle is a knowledge management project that seeks to define symbiotic relationships between 3D graphics and formal knowledge representations (ontologies). 3D graphics provides geometric and visual content, in 2D and 3D CAD forms, and the capability to display systems knowledge. Because the data is so heterogeneous, and the interrelated data structures are complex, 3D graphics combined with ontologies provides mechanisms for navigating the data and visualizing relationships.

  12. Design Application Translates 2-D Graphics to 3-D Surfaces

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Fabric Images Inc., specializing in the printing and manufacturing of fabric tension architecture for the retail, museum, and exhibit/tradeshow communities, designed software to translate 2-D graphics for 3-D surfaces prior to print production. Fabric Images' fabric-flattening design process models a 3-D surface based on computer-aided design (CAD) specifications. The surface geometry of the model is used to form a 2-D template, similar to a flattening process developed by NASA's Glenn Research Center. This template or pattern is then applied in the development of a 2-D graphic layout. Benefits of this process include 11.5 percent time savings per project, less material wasted, and the ability to improve upon graphic techniques and offer new design services. Partners include Exhibitgroup/Giltspur (end-user client: TAC Air, a division of Truman Arnold Companies Inc.), Jack Morton Worldwide (end-user client: Nickelodeon), as well as 3D Exhibits Inc., and MG Design Associates Corp.

  13. 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.

  14. Computer Graphics Special Issue on 1992 Symposium on Interactive 3D graphics Held in Cambridge, Massachusetts on 29 March-1 April 1992

    DTIC Science & Technology

    1992-01-01

    ubtd to addiess the iateiial Thi nllng i s dle )oil hope )Uu hke %% hat yout btk Omc t ,, 1lWaa ,i Sen.)ti it% to the miatcrial %%hich is illpoultalt...reshape the patient’s skin to replace to manipulate points and polygons, or nodal points and elements of missing tissue while minimizing distortion of the...allowing the surgeon to draw the on the patient’s skin with a marker, as is done when the surgery is surgical plan directly on a 3D model of the

  15. The three-dimensional Event-Driven Graphics Environment (3D-EDGE)

    NASA Technical Reports Server (NTRS)

    Freedman, Jeffrey; Hahn, Roger; Schwartz, David M.

    1993-01-01

    Stanford Telecom developed the Three-Dimensional Event-Driven Graphics Environment (3D-EDGE) for NASA GSFC's (GSFC) Communications Link Analysis and Simulation System (CLASS). 3D-EDGE consists of a library of object-oriented subroutines which allow engineers with little or no computer graphics experience to programmatically manipulate, render, animate, and access complex three-dimensional objects.

  16. A computer-controlled near-field electrospinning setup and its graphic user interface for precision patterning of functional nanofibers on 2D and 3D substrates.

    PubMed

    Bisht, Gobind; Nesterenko, Sergiy; Kulinsky, Lawrence; Madou, Marc

    2012-08-01

    Electrospinning is a versatile technique for production of nanofibers. However, it lacks the precision and control necessary for fabrication of nanofiber-based devices. The positional control of the nanofiber placement can be dramatically improved using low-voltage near-field electrospinning (LV-NFES). LV-NFES allows nanofibers to be patterned on 2D and 3D substrates. However, use of NFES requires low working distance between the electrospinning nozzle and substrate, manual jet initiation, and precise substrate movement to control fiber deposition. Environmental factors such as humidity also need to be controlled. We developed a computer-controlled automation strategy for LV-NFES to improve performance and reliability. With this setup, the user is able to control the relevant sensor and actuator parameters through a custom graphic user interface application programmed on the C#.NET platform. The stage movement can be programmed as to achieve any desired nanofiber pattern and thickness. The nanofiber generation step is initiated through a software-controlled linear actuator. Parameter setting files can be saved into an Excel sheet and can be used subsequently in running multiple experiments. Each experiment is automatically video recorded and stamped with the pertinent real-time parameters. Humidity is controlled with ±3% accuracy through a feedback loop. Further improvements, such as real-time droplet size control for feed rate regulation are in progress.

  17. Optimization Techniques for 3D Graphics Deployment on Mobile Devices

    NASA Astrophysics Data System (ADS)

    Koskela, Timo; Vatjus-Anttila, Jarkko

    2015-03-01

    3D Internet technologies are becoming essential enablers in many application areas including games, education, collaboration, navigation and social networking. The use of 3D Internet applications with mobile devices provides location-independent access and richer use context, but also performance issues. Therefore, one of the important challenges facing 3D Internet applications is the deployment of 3D graphics on mobile devices. In this article, we present an extensive survey on optimization techniques for 3D graphics deployment on mobile devices and qualitatively analyze the applicability of each technique from the standpoints of visual quality, performance and energy consumption. The analysis focuses on optimization techniques related to data-driven 3D graphics deployment, because it supports off-line use, multi-user interaction, user-created 3D graphics and creation of arbitrary 3D graphics. The outcome of the analysis facilitates the development and deployment of 3D Internet applications on mobile devices and provides guidelines for future research.

  18. DspaceOgre 3D Graphics Visualization Tool

    NASA Technical Reports Server (NTRS)

    Jain, Abhinandan; Myin, Steven; Pomerantz, Marc I.

    2011-01-01

    This general-purpose 3D graphics visualization C++ tool is designed for visualization of simulation and analysis data for articulated mechanisms. Examples of such systems are vehicles, robotic arms, biomechanics models, and biomolecular structures. DspaceOgre builds upon the open-source Ogre3D graphics visualization library. It provides additional classes to support the management of complex scenes involving multiple viewpoints and different scene groups, and can be used as a remote graphics server. This software provides improved support for adding programs at the graphics processing unit (GPU) level for improved performance. It also improves upon the messaging interface it exposes for use as a visualization server.

  19. Computer graphics and the graphic artist

    NASA Technical Reports Server (NTRS)

    Taylor, N. L.; Fedors, E. G.; Pinelli, T. E.

    1985-01-01

    A centralized computer graphics system is being developed at the NASA Langley Research Center. This system was required to satisfy multiuser needs, ranging from presentation quality graphics prepared by a graphic artist to 16-mm movie simulations generated by engineers and scientists. While the major thrust of the central graphics system was directed toward engineering and scientific applications, hardware and software capabilities to support the graphic artists were integrated into the design. This paper briefly discusses the importance of computer graphics in research; the central graphics system in terms of systems, software, and hardware requirements; the application of computer graphics to graphic arts, discussed in terms of the requirements for a graphic arts workstation; and the problems encountered in applying computer graphics to the graphic arts. The paper concludes by presenting the status of the central graphics system.

  20. Computer graphics and the graphic artist

    NASA Technical Reports Server (NTRS)

    Taylor, N. L.; Fedors, E. G.; Pinelli, T. E.

    1985-01-01

    A centralized computer graphics system is being developed at the NASA Langley Research Center. This system was required to satisfy multiuser needs, ranging from presentation quality graphics prepared by a graphic artist to 16-mm movie simulations generated by engineers and scientists. While the major thrust of the central graphics system was directed toward engineering and scientific applications, hardware and software capabilities to support the graphic artists were integrated into the design. This paper briefly discusses the importance of computer graphics in research; the central graphics system in terms of systems, software, and hardware requirements; the application of computer graphics to graphic arts, discussed in terms of the requirements for a graphic arts workstation; and the problems encountered in applying computer graphics to the graphic arts. The paper concludes by presenting the status of the central graphics system.

  1. Creating Realistic 3D Graphics with Excel at High School--Vector Algebra in Practice

    ERIC Educational Resources Information Center

    Benacka, Jan

    2015-01-01

    The article presents the results of an experiment in which Excel applications that depict rotatable and sizable orthographic projection of simple 3D figures with face overlapping were developed with thirty gymnasium (high school) students of age 17-19 as an introduction to 3D computer graphics. A questionnaire survey was conducted to find out…

  2. How Computer Graphics Work.

    ERIC Educational Resources Information Center

    Prosise, Jeff

    This document presents the principles behind modern computer graphics without straying into the arcane languages of mathematics and computer science. Illustrations accompany the clear, step-by-step explanations that describe how computers draw pictures. The 22 chapters of the book are organized into 5 sections. "Part 1: Computer Graphics in…

  3. Spidergl: a Graphics Library for 3d Web Applications

    NASA Astrophysics Data System (ADS)

    Di Benedetto, M.; Corsini, M.; Scopigno, R.

    2011-09-01

    The recent introduction of the WebGL API for leveraging the power of 3D graphics accelerators within Web browsers opens the possibility to develop advanced graphics applications without the need for an ad-hoc plug-in. There are several contexts in which this new technology can be exploited to enhance user experience and data fruition, like e-commerce applications, games and, in particular, Cultural Heritage. In fact, it is now possible to use the Web platform to present a virtual reconstruction hypothesis of ancient pasts, to show detailed 3D models of artefacts of interests to a wide public, and to create virtual museums. We introduce SpiderGL, a JavaScript library for developing 3D graphics Web applications. SpiderGL provides data structures and algorithms to ease the use of WebGL, to define and manipulate shapes, to import 3D models in various formats, and to handle asynchronous data loading. We show the potential of this novel library with a number of demo applications and give details about its future uses in the context of Cultural Heritage applications.

  4. MAP3D: a media processor approach for high-end 3D graphics

    NASA Astrophysics Data System (ADS)

    Darsa, Lucia; Stadnicki, Steven; Basoglu, Chris

    1999-12-01

    Equator Technologies, Inc. has used a software-first approach to produce several programmable and advanced VLIW processor architectures that have the flexibility to run both traditional systems tasks and an array of media-rich applications. For example, Equator's MAP1000A is the world's fastest single-chip programmable signal and image processor targeted for digital consumer and office automation markets. The Equator MAP3D is a proposal for the architecture of the next generation of the Equator MAP family. The MAP3D is designed to achieve high-end 3D performance and a variety of customizable special effects by combining special graphics features with high performance floating-point and media processor architecture. As a programmable media processor, it offers the advantages of a completely configurable 3D pipeline--allowing developers to experiment with different algorithms and to tailor their pipeline to achieve the highest performance for a particular application. With the support of Equator's advanced C compiler and toolkit, MAP3D programs can be written in a high-level language. This allows the compiler to successfully find and exploit any parallelism in a programmer's code, thus decreasing the time to market of a given applications. The ability to run an operating system makes it possible to run concurrent applications in the MAP3D chip, such as video decoding while executing the 3D pipelines, so that integration of applications is easily achieved--using real-time decoded imagery for texturing 3D objects, for instance. This novel architecture enables an affordable, integrated solution for high performance 3D graphics.

  5. Evaluation of 3-D graphics software: A case study

    NASA Technical Reports Server (NTRS)

    Lores, M. E.; Chasen, S. H.; Garner, J. M.

    1984-01-01

    An efficient 3-D geometry graphics software package which is suitable for advanced design studies was developed. The advanced design system is called GRADE--Graphics for Advanced Design. Efficiency and ease of use are gained by sacrificing flexibility in surface representation. The immediate options were either to continue development of GRADE or to acquire a commercially available system which would replace or complement GRADE. Test cases which would reveal the ability of each system to satisfy the requirements were developed. A scoring method which adequately captured the relative capabilities of the three systems was presented. While more complex multi-attribute decision methods could be used, the selected method provides all the needed information without being so complex that it is difficult to understand. If the value factors are modestly perturbed, system Z is a clear winner based on its overall capabilities. System Z is superior in two vital areas: surfacing and ease of interface with application programs.

  6. 3D Computations and Experiments

    SciTech Connect

    Couch, R; Faux, D; Goto, D; Nikkel, D

    2004-04-05

    This project consists of two activities. Task A, Simulations and Measurements, combines all the material model development and associated numerical work with the materials-oriented experimental activities. The goal of this effort is to provide an improved understanding of dynamic material properties and to provide accurate numerical representations of those properties for use in analysis codes. Task B, ALE3D Development, involves general development activities in the ALE3D code with the focus of improving simulation capabilities for problems of mutual interest to DoD and DOE. Emphasis is on problems involving multi-phase flow, blast loading of structures and system safety/vulnerability studies.

  7. John C. Belland: A Pioneer in 3D Graphics.

    ERIC Educational Resources Information Center

    Hay, Kenneth

    2000-01-01

    Provides a profile of the career of John Belland and his work in instructional technology. Highlights include his educational background, teaching experience in higher education, work in learning with 3D computer-generated animation, alternative paradigms of instructional design, and ideas of postmodernism. (LRW)

  8. Space Spurred Computer Graphics

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Dicomed Corporation was asked by NASA in the early 1970s to develop processing capabilities for recording images sent from Mars by Viking spacecraft. The company produced a film recorder which increased the intensity levels and the capability for color recording. This development led to a strong technology base resulting in sophisticated computer graphics equipment. Dicomed systems are used to record CAD (computer aided design) and CAM (computer aided manufacturing) equipment, to update maps and produce computer generated animation.

  9. Computer Graphics Verification

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Video processing creates technical animation sequences using studio quality equipment to realistically represent fluid flow over space shuttle surfaces, helicopter rotors, and turbine blades.Computer systems Co-op, Tim Weatherford, performing computer graphics verification. Part of Co-op brochure.

  10. Computing Graphical Confidence Bounds

    NASA Technical Reports Server (NTRS)

    Mezzacappa, M. A.

    1983-01-01

    Approximation for graphical confidence bounds is simple enough to run on programmable calculator. Approximation is used in lieu of numerical tables not always available, and exact calculations, which often require rather sizable computer resources. Approximation verified for collection of up to 50 data points. Method used to analyze tile-strength data on Space Shuttle thermal-protection system.

  11. Computing Graphical Confidence Bounds

    NASA Technical Reports Server (NTRS)

    Mezzacappa, M. A.

    1983-01-01

    Approximation for graphical confidence bounds is simple enough to run on programmable calculator. Approximation is used in lieu of numerical tables not always available, and exact calculations, which often require rather sizable computer resources. Approximation verified for collection of up to 50 data points. Method used to analyze tile-strength data on Space Shuttle thermal-protection system.

  12. Towards a More Effective Use of 3D-Graphics in Mathematics Education--Utilisation of KETpic to Insert Figures into LATEX Documents

    ERIC Educational Resources Information Center

    Kitahara, Kiyoshi; Abe, Takayuki; Kaneko, Masataka; Yamashita, Satoshi; Takato, Setsuo

    2010-01-01

    Computer Algebra Systems (CAS) are equipped with rich facilities to show graphics, so the use of CAS to show 3D-graphics on screen is a popular tool for mathematics education. However, showing 3D-graphics in mass printed materials is a different story, since the clarity and preciseness of figures tend to be lost. To fill this gap, we developed…

  13. Towards a More Effective Use of 3D-Graphics in Mathematics Education--Utilisation of KETpic to Insert Figures into LATEX Documents

    ERIC Educational Resources Information Center

    Kitahara, Kiyoshi; Abe, Takayuki; Kaneko, Masataka; Yamashita, Satoshi; Takato, Setsuo

    2010-01-01

    Computer Algebra Systems (CAS) are equipped with rich facilities to show graphics, so the use of CAS to show 3D-graphics on screen is a popular tool for mathematics education. However, showing 3D-graphics in mass printed materials is a different story, since the clarity and preciseness of figures tend to be lost. To fill this gap, we developed…

  14. Learning from graphically integrated 2D and 3D representations improves retention of neuroanatomy

    NASA Astrophysics Data System (ADS)

    Naaz, Farah

    Visualizations in the form of computer-based learning environments are highly encouraged in science education, especially for teaching spatial material. Some spatial material, such as sectional neuroanatomy, is very challenging to learn. It involves learning the two dimensional (2D) representations that are sampled from the three dimensional (3D) object. In this study, a computer-based learning environment was used to explore the hypothesis that learning sectional neuroanatomy from a graphically integrated 2D and 3D representation will lead to better learning outcomes than learning from a sequential presentation. The integrated representation explicitly demonstrates the 2D-3D transformation and should lead to effective learning. This study was conducted using a computer graphical model of the human brain. There were two learning groups: Whole then Sections, and Integrated 2D3D. Both groups learned whole anatomy (3D neuroanatomy) before learning sectional anatomy (2D neuroanatomy). The Whole then Sections group then learned sectional anatomy using 2D representations only. The Integrated 2D3D group learned sectional anatomy from a graphically integrated 3D and 2D model. A set of tests for generalization of knowledge to interpreting biomedical images was conducted immediately after learning was completed. The order of presentation of the tests of generalization of knowledge was counterbalanced across participants to explore a secondary hypothesis of the study: preparation for future learning. If the computer-based instruction programs used in this study are effective tools for teaching anatomy, the participants should continue learning neuroanatomy with exposure to new representations. A test of long-term retention of sectional anatomy was conducted 4-8 weeks after learning was completed. The Integrated 2D3D group was better than the Whole then Sections

  15. Career Opportunities in Computer Graphics.

    ERIC Educational Resources Information Center

    Langer, Victor

    1983-01-01

    Reviews the impact of computer graphics on industrial productivity. Details the computer graphics technician curriculum at Milwaukee Area Technical College and the cooperative efforts of business and industry to fund and equip the program. (SK)

  16. Efficient Computation of 3D Clipped Voronoi Diagram

    NASA Astrophysics Data System (ADS)

    Yan, Dong-Ming; Wang, Wenping; Lévy, Bruno; Liu, Yang

    The Voronoi diagram is a fundamental geometry structure widely used in various fields, especially in computer graphics and geometry computing. For a set of points in a compact 3D domain (i.e. a finite 3D volume), some Voronoi cells of their Voronoi diagram are infinite, but in practice only the parts of the cells inside the domain are needed, as when computing the centroidal Voronoi tessellation. Such a Voronoi diagram confined to a compact domain is called a clipped Voronoi diagram. We present an efficient algorithm for computing the clipped Voronoi diagram for a set of sites with respect to a compact 3D volume, assuming that the volume is represented as a tetrahedral mesh. We also describe an application of the proposed method to implementing a fast method for optimal tetrahedral mesh generation based on the centroidal Voronoi tessellation.

  17. Computer graphics in aerodynamic analysis

    NASA Technical Reports Server (NTRS)

    Cozzolongo, J. V.

    1984-01-01

    The use of computer graphics and its application to aerodynamic analyses on a routine basis is outlined. The mathematical modelling of the aircraft geometries and the shading technique implemented are discussed. Examples of computer graphics used to display aerodynamic flow field data and aircraft geometries are shown. A future need in computer graphics for aerodynamic analyses is addressed.

  18. Intraoperative 3D Computed Tomography: Spine Surgery.

    PubMed

    Adamczak, Stephanie E; Bova, Frank J; Hoh, Daniel J

    2017-10-01

    Spinal instrumentation often involves placing implants without direct visualization of their trajectory or proximity to adjacent neurovascular structures. Two-dimensional fluoroscopy is commonly used to navigate implant placement, but with the advent of computed tomography, followed by the invention of a mobile scanner with an open gantry, three-dimensional (3D) navigation is now widely used. This article critically appraises the available literature to assess the influence of 3D navigation on radiation exposure, accuracy of instrumentation, operative time, and patient outcomes. Also explored is the latest technological advance in 3D neuronavigation: the manufacturing of, via 3D printers, patient-specific templates that direct implant placement. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Computational challenges of emerging novel true 3D holographic displays

    NASA Astrophysics Data System (ADS)

    Cameron, Colin D.; Pain, Douglas A.; Stanley, Maurice; Slinger, Christopher W.

    2000-11-01

    A hologram can produce all the 3D depth cues that the human visual system uses to interpret and perceive real 3D objects. As such it is arguably the ultimate display technology. Computer generated holography, in which a computer calculates a hologram that is then displayed using a highly complex modulator, combines the ultimate qualities of a traditional hologram with the dynamic capabilities of a computer display producing a true 3D real image floating in space. This technology is set to emerge over the next decade, potentially revolutionizing application areas such as virtual prototyping (CAD-CAM, CAID etc.), tactical information displays, data visualization and simulation. In this paper we focus on the computational challenges of this technology. We consider different classes of computational algorithms from true computer-generated holograms (CGH) to holographic stereograms. Each has different characteristics in terms of image qualities, computational resources required, total CGH information content, and system performance. Possible trade- offs will be discussed including reducing the parallax. The software and hardware architectures used to implement the CGH algorithms have many possible forms. Different schemes, from high performance computing architectures to graphics based cluster architectures will be discussed and compared. Assessment will be made of current and future trends looking forward to a practical dynamic CGH based 3D display.

  20. Whole versus Part Presentations of the Interactive 3D Graphics Learning Objects

    ERIC Educational Resources Information Center

    Azmy, Nabil Gad; Ismaeel, Dina Ahmed

    2010-01-01

    The purpose of this study is to present an analysis of how the structure and design of the Interactive 3D Graphics Learning Objects can be effective and efficient in terms of Performance, Time on task, and Learning Efficiency. The study explored two treatments, namely whole versus Part Presentations of the Interactive 3D Graphics Learning Objects,…

  1. Whole versus Part Presentations of the Interactive 3D Graphics Learning Objects

    ERIC Educational Resources Information Center

    Azmy, Nabil Gad; Ismaeel, Dina Ahmed

    2010-01-01

    The purpose of this study is to present an analysis of how the structure and design of the Interactive 3D Graphics Learning Objects can be effective and efficient in terms of Performance, Time on task, and Learning Efficiency. The study explored two treatments, namely whole versus Part Presentations of the Interactive 3D Graphics Learning Objects,…

  2. Extensible 3D (X3D) Graphics Clouds for Geographic Information Systems

    DTIC Science & Technology

    2008-03-01

    browser such as Microsoft Internet Explorer or Netscape using an X3D or VRML supporting plug-in. The benefits of diverse support can cause...typing model output with a particular method of 3D cloud production. Data-driven adaptation and production of cloud models for web -based delivery...and production of cloud models for web -based delivery is an achievable capability given continued research and development. vi THIS PAGE

  3. Standard Features and Their Impact on 3D Engineering Graphics

    ERIC Educational Resources Information Center

    Waldenmeyer, K. M.; Hartman, N. W.

    2009-01-01

    The prevalence of feature-based 3D modeling in industry has necessitated the accumulation and maintenance of standard feature libraries. Currently, firms who use standard features to design parts are storing and utilizing these libraries through their existing product data management (PDM) systems. Standard features have enabled companies to…

  4. Standard Features and Their Impact on 3D Engineering Graphics

    ERIC Educational Resources Information Center

    Waldenmeyer, K. M.; Hartman, N. W.

    2009-01-01

    The prevalence of feature-based 3D modeling in industry has necessitated the accumulation and maintenance of standard feature libraries. Currently, firms who use standard features to design parts are storing and utilizing these libraries through their existing product data management (PDM) systems. Standard features have enabled companies to…

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

    PubMed

    Berkelman, Peter; Miyasaka, Muneaki; Bozlee, Sebastian

    2013-01-01

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

  6. Development and New Directions for the RELAP5-3D Graphical Users Interface

    SciTech Connect

    Mesina, George Lee

    2001-09-01

    The direction of development for the RELAP5 Graphical User Interfaces (RGUI) has been extended. In addition to existing plans for displaying all aspects of RELAP5 calculations, the plan now includes plans to display the calculations of a variety of codes including SCDAP, RETRAN and FLUENT. Recent work has included such extensions along with the previously planned and user-requested improvements and extensions. Visualization of heat-structures has been added. Adaptations were made for another computer program, SCDAP-3D, including plant core views. An input model builder for generating RELAP5-3D input files was partially implemented. All these are reported. Plans for future work are also summarized. These include an input processor that transfers steady-state conditions into an input file.

  7. Interactive Computer Graphics

    NASA Technical Reports Server (NTRS)

    Kenwright, David

    2000-01-01

    Aerospace data analysis tools that significantly reduce the time and effort needed to analyze large-scale computational fluid dynamics simulations have emerged this year. The current approach for most postprocessing and visualization work is to explore the 3D flow simulations with one of a dozen or so interactive tools. While effective for analyzing small data sets, this approach becomes extremely time consuming when working with data sets larger than one gigabyte. An active area of research this year has been the development of data mining tools that automatically search through gigabyte data sets and extract the salient features with little or no human intervention. With these so-called feature extraction tools, engineers are spared the tedious task of manually exploring huge amounts of data to find the important flow phenomena. The software tools identify features such as vortex cores, shocks, separation and attachment lines, recirculation bubbles, and boundary layers. Some of these features can be extracted in a few seconds; others take minutes to hours on extremely large data sets. The analysis can be performed off-line in a batch process, either during or following the supercomputer simulations. These computations have to be performed only once, because the feature extraction programs search the entire data set and find every occurrence of the phenomena being sought. Because the important questions about the data are being answered automatically, interactivity is less critical than it is with traditional approaches.

  8. Computer Graphics Evolution: A Survey.

    ERIC Educational Resources Information Center

    Gartel, Laurence M.

    1985-01-01

    The history of the field of computer graphics is discussed. In 1976 there were no institutions that offered any kind of study of computer graphics. Today electronic image-making is seen as a viable, legitimate art form, and courses are offered by many universities and colleges. (RM)

  9. Computer Graphics Using Raytracing

    NASA Astrophysics Data System (ADS)

    Sellers, Graham; Lukac, Rastislav

    In the field of computer graphics, almost any technique for generating an output image can be viewed as a data transformation. The output image is a function of some input data set and the rendering algorithms used to generate that image are mapping functions. The source of the data set may be explicit, such as models and structures produced by an artist or designer, or be implicit, such as the result of a physical simulation or the surface of a fractal. There are many methods for transforming the input visual scene description into the target image. Rasterization, the process of converting an image described in vector for into a raster image [Foley 90] is a popular technique, particularly useful in modern, hardware accelerated systems. However, it tends to break down, losing its efficiency and attractiveness when scene complexity increases and geometric primitives shrink in size. Furthermore, since rasterization methods are often tuned to render simple geometry such as triangles, direct rasterization of implicit surfaces such as quadrics is not straight forward. In offline systems, a commonly used algorithm for the rendering of very fine geometry and implicit surfaces is the Reyes algorithm [Cook 87]. The Reyes algorithm, developed in the mid 1980s by a group that was to become Pixar, renders implicit geometry and smooth surfaces by recursively subdividing it into polygons until each facet becomes smaller than a single pixel. Each polygon is then rendered as a flat, single colored primitive.

  10. Calculators and Computers: Graphical Addition.

    ERIC Educational Resources Information Center

    Spero, Samuel W.

    1978-01-01

    A computer program is presented that generates problem sets involving sketching graphs of trigonometric functions using graphical addition. The students use calculators to sketch the graphs and a computer solution is used to check it. (MP)

  11. Interactive 3-D graphics workstations in stereotaxy: clinical requirements, algorithms, and solutions

    NASA Astrophysics Data System (ADS)

    Ehricke, Hans-Heino; Daiber, Gerhard; Sonntag, Ralf; Strasser, Wolfgang; Lochner, Mathias; Rudi, Lothar S.; Lorenz, Walter J.

    1992-09-01

    In stereotactic treatment planning the spatial relationships between a variety of objects has to be taken into account in order to avoid destruction of vital brain structures and rupture of vasculature. The visualization of these highly complex relations may be supported by 3-D computer graphics methods. In this context the three-dimensional display of the intracranial vascular tree and additional objects, such as neuroanatomy, pathology, stereotactic devices, or isodose surfaces, is of high clinical value. We report an advanced rendering method for a depth-enhanced maximum intensity projection from magnetic resonance angiography (MRA) and a walk-through approach to the analysis of MRA volume data. Furthermore, various methods for a multiple-object 3-D rendering in stereotaxy are discussed. The development of advanced applications in medical imaging can hardly be successful if image acquisition problems are disregarded. We put particular emphasis on the use of conventional MRI and MRA for stereotactic guidance. The problem of MR distortion is discussed and a novel three- dimensional approach to the quantification and correction of the distortion patterns is presented. Our results suggest that the sole use of MR for stereotactic guidance is highly practical. The true three-dimensionality of the acquired datasets opens up new perspectives to stereotactic treatment planning. For the first time it is possible now to integrate all the necessary information into 3-D scenes, thus enabling an interactive 3-D planning.

  12. Flowfield computer graphics

    NASA Technical Reports Server (NTRS)

    Desautel, Richard

    1993-01-01

    The objectives of this research include supporting the Aerothermodynamics Branch's research by developing graphical visualization tools for both the branch's adaptive grid code and flow field ray tracing code. The completed research for the reporting period includes development of a graphical user interface (GUI) and its implementation into the NAS Flowfield Analysis Software Tool kit (FAST), for both the adaptive grid code (SAGE) and the flow field ray tracing code (CISS).

  13. Compressed sensing reconstruction for whole-heart imaging with 3D radial trajectories: a graphics processing unit implementation.

    PubMed

    Nam, Seunghoon; Akçakaya, Mehmet; Basha, Tamer; Stehning, Christian; Manning, Warren J; Tarokh, Vahid; Nezafat, Reza

    2013-01-01

    A disadvantage of three-dimensional (3D) isotropic acquisition in whole-heart coronary MRI is the prolonged data acquisition time. Isotropic 3D radial trajectories allow undersampling of k-space data in all three spatial dimensions, enabling accelerated acquisition of the volumetric data. Compressed sensing (CS) reconstruction can provide further acceleration in the acquisition by removing the incoherent artifacts due to undersampling and improving the image quality. However, the heavy computational overhead of the CS reconstruction has been a limiting factor for its application. In this article, a parallelized implementation of an iterative CS reconstruction method for 3D radial acquisitions using a commercial graphics processing unit is presented. The execution time of the graphics processing unit-implemented CS reconstruction was compared with that of the C++ implementation, and the efficacy of the undersampled 3D radial acquisition with CS reconstruction was investigated in both phantom and whole-heart coronary data sets. Subsequently, the efficacy of CS in suppressing streaking artifacts in 3D whole-heart coronary MRI with 3D radial imaging and its convergence properties were studied. The CS reconstruction provides improved image quality (in terms of vessel sharpness and suppression of noise-like artifacts) compared with the conventional 3D gridding algorithm, and the graphics processing unit implementation greatly reduces the execution time of CS reconstruction yielding 34-54 times speed-up compared with C++ implementation. Copyright © 2012 Wiley Periodicals, Inc.

  14. Computer Graphics Research Laboratory

    DTIC Science & Technology

    1994-01-31

    and strength data. Loads or 3D external forces can be applied to any body point. Inverse dynamics using the Newton -Euler method is applied to a 97 DOF...legged figure. Stewart and Cremer used a dynamics simulator Newton , to produce the animation of biped climbing and descending [36]. Bruderlin and Calvert...Hartenberg notation [12] and Newton -Euler dynamics (recursive method) [26, 11] - stan- dard techniques in robotics - are applied. Loads or general 3D

  15. Simulating 3-D lung dynamics using a programmable graphics processing unit.

    PubMed

    Santhanam, Anand P; Hamza-Lup, Felix G; Rolland, Jannick P

    2007-09-01

    Medical simulations of lung dynamics promise to be effective tools for teaching and training clinical and surgical procedures related to lungs. Their effectiveness may be greatly enhanced when visualized in an augmented reality (AR) environment. However, the computational requirements of AR environments limit the availability of the central processing unit (CPU) for the lung dynamics simulation for different breathing conditions. In this paper, we present a method for computing lung deformations in real time by taking advantage of the programmable graphics processing unit (GPU). This will save the CPU time for other AR-associated tasks such as tracking, communication, and interaction management. An approach for the simulations of the three-dimensional (3-D) lung dynamics using Green's formulation in the case of upright position is taken into consideration. We extend this approach to other orientations as well as the subsequent changes in breathing. Specifically, the proposed extension presents a computational optimization and its implementation in a GPU. Results show that the computational requirements for simulating the deformation of a 3-D lung model are significantly reduced for point-based rendering.

  16. Monte Carlo simulation of photon migration in 3D turbid media accelerated by graphics processing units.

    PubMed

    Fang, Qianqian; Boas, David A

    2009-10-26

    We report a parallel Monte Carlo algorithm accelerated by graphics processing units (GPU) for modeling time-resolved photon migration in arbitrary 3D turbid media. By taking advantage of the massively parallel threads and low-memory latency, this algorithm allows many photons to be simulated simultaneously in a GPU. To further improve the computational efficiency, we explored two parallel random number generators (RNG), including a floating-point-only RNG based on a chaotic lattice. An efficient scheme for boundary reflection was implemented, along with the functions for time-resolved imaging. For a homogeneous semi-infinite medium, good agreement was observed between the simulation output and the analytical solution from the diffusion theory. The code was implemented with CUDA programming language, and benchmarked under various parameters, such as thread number, selection of RNG and memory access pattern. With a low-cost graphics card, this algorithm has demonstrated an acceleration ratio above 300 when using 1792 parallel threads over conventional CPU computation. The acceleration ratio drops to 75 when using atomic operations. These results render the GPU-based Monte Carlo simulation a practical solution for data analysis in a wide range of diffuse optical imaging applications, such as human brain or small-animal imaging.

  17. Real time 3D structural and Doppler OCT imaging on graphics processing units

    NASA Astrophysics Data System (ADS)

    Sylwestrzak, Marcin; Szlag, Daniel; Szkulmowski, Maciej; Gorczyńska, Iwona; Bukowska, Danuta; Wojtkowski, Maciej; Targowski, Piotr

    2013-03-01

    In this report the application of graphics processing unit (GPU) programming for real-time 3D Fourier domain Optical Coherence Tomography (FdOCT) imaging with implementation of Doppler algorithms for visualization of the flows in capillary vessels is presented. Generally, the time of the data processing of the FdOCT data on the main processor of the computer (CPU) constitute a main limitation for real-time imaging. Employing additional algorithms, such as Doppler OCT analysis, makes this processing even more time consuming. Lately developed GPUs, which offers a very high computational power, give a solution to this problem. Taking advantages of them for massively parallel data processing, allow for real-time imaging in FdOCT. The presented software for structural and Doppler OCT allow for the whole processing with visualization of 2D data consisting of 2000 A-scans generated from 2048 pixels spectra with frame rate about 120 fps. The 3D imaging in the same mode of the volume data build of 220 × 100 A-scans is performed at a rate of about 8 frames per second. In this paper a software architecture, organization of the threads and optimization applied is shown. For illustration the screen shots recorded during real time imaging of the phantom (homogeneous water solution of Intralipid in glass capillary) and the human eye in-vivo is presented.

  18. Internet-based hardware/software co-design framework for embedded 3D graphics applications

    NASA Astrophysics Data System (ADS)

    Yeh, Chi-Tsai; Wang, Chun-Hao; Huang, Ing-Jer; Wong, Weng-Fai

    2011-12-01

    Advances in technology are making it possible to run three-dimensional (3D) graphics applications on embedded and handheld devices. In this article, we propose a hardware/software co-design environment for 3D graphics application development that includes the 3D graphics software, OpenGL ES application programming interface (API), device driver, and 3D graphics hardware simulators. We developed a 3D graphics system-on-a-chip (SoC) accelerator using transaction-level modeling (TLM). This gives software designers early access to the hardware even before it is ready. On the other hand, hardware designers also stand to gain from the more complex test benches made available in the software for verification. A unique aspect of our framework is that it allows hardware and software designers from geographically dispersed areas to cooperate and work on the same framework. Designs can be entered and executed from anywhere in the world without full access to the entire framework, which may include proprietary components. This results in controlled and secure transparency and reproducibility, granting leveled access to users of various roles.

  19. Computer Graphics. Curriculum Guide for Technology Education.

    ERIC Educational Resources Information Center

    Craft, Clyde O.

    This curriculum guide for a 1-quarter or 1-semester course in computer graphics is designed to be used with Apple II computers. Some of the topics covered include the following: computer graphics terminology and applications, operating Apple computers, graphics programming in BASIC using various programs and commands, computer graphics painting,…

  20. Computer Graphics. Curriculum Guide for Technology Education.

    ERIC Educational Resources Information Center

    Craft, Clyde O.

    This curriculum guide for a 1-quarter or 1-semester course in computer graphics is designed to be used with Apple II computers. Some of the topics covered include the following: computer graphics terminology and applications, operating Apple computers, graphics programming in BASIC using various programs and commands, computer graphics painting,…

  1. Computer Assisted Cancer Device - 3D Imaging

    DTIC Science & Technology

    2006-10-01

    tomosynthesis images of the breast. iCAD has identified several sources of 3D tomosynthesis data, and has begun adapting its image analysis...collaborative relationships with major manufacturers of tomosynthesis equipment. 21. iCAD believes that tomosynthesis , a 3D breast imaging technique...purported advantages of tomosynthesis relative to conventional mammography include; improved lesion visibility, improved lesion detectability and

  2. Young Children Use Computer Graphics.

    ERIC Educational Resources Information Center

    Piestrup, Ann M.

    This paper describes the origins of a corporation producing computer software for children, lists criteria for software design, and describes work done with computer graphics for children. The corporation, called The Learning Company, had its origins in a project set up to create playful learning programs for children ages 3 to 13. The project was…

  3. A streaming-based solution for remote visualization of 3D graphics on mobile devices.

    PubMed

    Lamberti, Fabrizio; Sanna, Andrea

    2007-01-01

    Mobile devices such as Personal Digital Assistants, Tablet PCs, and cellular phones have greatly enhanced user capability to connect to remote resources. Although a large set of applications are now available bridging the gap between desktop and mobile devices, visualization of complex 3D models is still a task hard to accomplish without specialized hardware. This paper proposes a system where a cluster of PCs, equipped with accelerated graphics cards managed by the Chromium software, is able to handle remote visualization sessions based on MPEG video streaming involving complex 3D models. The proposed framework allows mobile devices such as smart phones, Personal Digital Assistants (PDAs), and Tablet PCs to visualize objects consisting of millions of textured polygons and voxels at a frame rate of 30 fps or more depending on hardware resources at the server side and on multimedia capabilities at the client side. The server is able to concurrently manage multiple clients computing a video stream for each one; resolution and quality of each stream is tailored according to screen resolution and bandwidth of the client. The paper investigates in depth issues related to latency time, bit rate and quality of the generated stream, screen resolutions, as well as frames per second displayed.

  4. Use of a graphics processing unit (GPU) to facilitate real-time 3D graphic presentation of the patient skin-dose distribution during fluoroscopic interventional procedures

    PubMed Central

    Rana, Vijay; Rudin, Stephen; Bednarek, Daniel R.

    2012-01-01

    We have developed a dose-tracking system (DTS) that calculates the radiation dose to the patient’s skin in real-time by acquiring exposure parameters and imaging-system-geometry from the digital bus on a Toshiba Infinix C-arm unit. The cumulative dose values are then displayed as a color map on an OpenGL-based 3D graphic of the patient for immediate feedback to the interventionalist. Determination of those elements on the surface of the patient 3D-graphic that intersect the beam and calculation of the dose for these elements in real time demands fast computation. Reducing the size of the elements results in more computation load on the computer processor and therefore a tradeoff occurs between the resolution of the patient graphic and the real-time performance of the DTS. The speed of the DTS for calculating dose to the skin is limited by the central processing unit (CPU) and can be improved by using the parallel processing power of a graphics processing unit (GPU). Here, we compare the performance speed of GPU-based DTS software to that of the current CPU-based software as a function of the resolution of the patient graphics. Results show a tremendous improvement in speed using the GPU. While an increase in the spatial resolution of the patient graphics resulted in slowing down the computational speed of the DTS on the CPU, the speed of the GPU-based DTS was hardly affected. This GPU-based DTS can be a powerful tool for providing accurate, real-time feedback about patient skin-dose to physicians while performing interventional procedures. PMID:24027616

  5. Use of a graphics processing unit (GPU) to facilitate real-time 3D graphic presentation of the patient skin-dose distribution during fluoroscopic interventional procedures.

    PubMed

    Rana, Vijay; Rudin, Stephen; Bednarek, Daniel R

    2012-02-23

    We have developed a dose-tracking system (DTS) that calculates the radiation dose to the patient's skin in real-time by acquiring exposure parameters and imaging-system-geometry from the digital bus on a Toshiba Infinix C-arm unit. The cumulative dose values are then displayed as a color map on an OpenGL-based 3D graphic of the patient for immediate feedback to the interventionalist. Determination of those elements on the surface of the patient 3D-graphic that intersect the beam and calculation of the dose for these elements in real time demands fast computation. Reducing the size of the elements results in more computation load on the computer processor and therefore a tradeoff occurs between the resolution of the patient graphic and the real-time performance of the DTS. The speed of the DTS for calculating dose to the skin is limited by the central processing unit (CPU) and can be improved by using the parallel processing power of a graphics processing unit (GPU). Here, we compare the performance speed of GPU-based DTS software to that of the current CPU-based software as a function of the resolution of the patient graphics. Results show a tremendous improvement in speed using the GPU. While an increase in the spatial resolution of the patient graphics resulted in slowing down the computational speed of the DTS on the CPU, the speed of the GPU-based DTS was hardly affected. This GPU-based DTS can be a powerful tool for providing accurate, real-time feedback about patient skin-dose to physicians while performing interventional procedures.

  6. Use of a graphics processing unit (GPU) to facilitate real-time 3D graphic presentation of the patient skin-dose distribution during fluoroscopic interventional procedures

    NASA Astrophysics Data System (ADS)

    Rana, Vijay; Rudin, Stephen; Bednarek, Daniel R.

    2012-03-01

    We have developed a dose-tracking system (DTS) that calculates the radiation dose to the patient's skin in realtime by acquiring exposure parameters and imaging-system-geometry from the digital bus on a Toshiba Infinix C-arm unit. The cumulative dose values are then displayed as a color map on an OpenGL-based 3D graphic of the patient for immediate feedback to the interventionalist. Determination of those elements on the surface of the patient 3D-graphic that intersect the beam and calculation of the dose for these elements in real time demands fast computation. Reducing the size of the elements results in more computation load on the computer processor and therefore a tradeoff occurs between the resolution of the patient graphic and the real-time performance of the DTS. The speed of the DTS for calculating dose to the skin is limited by the central processing unit (CPU) and can be improved by using the parallel processing power of a graphics processing unit (GPU). Here, we compare the performance speed of GPU-based DTS software to that of the current CPU-based software as a function of the resolution of the patient graphics. Results show a tremendous improvement in speed using the GPU. While an increase in the spatial resolution of the patient graphics resulted in slowing down the computational speed of the DTS on the CPU, the speed of the GPU-based DTS was hardly affected. This GPU-based DTS can be a powerful tool for providing accurate, real-time feedback about patient skin-dose to physicians while performing interventional procedures.

  7. Cp-curve, a Novel 3-D Graphical Representation of Proteins

    NASA Astrophysics Data System (ADS)

    Bai, Haihua; Li, Chun; Agula, Hasi; Jirimutu, Jirimutu; Wang, Jun; Xing, Lili

    2007-12-01

    Based on a five-letter model of the 20 amino acids, we propose a novel 3-D graphical representation of proteins. The method is illustrated on the mutant exon 1 of EDA gene of a Mongolian family with X-linked congenital anodontia/wavy hair.

  8. Revised adage graphics computer system

    NASA Technical Reports Server (NTRS)

    Tulppo, J. S.

    1980-01-01

    Bootstrap loader and mode-control options for Adage Graphics Computer System Significantly simplify operations procedures. Normal load and control functions are performed quickly and easily from control console. Operating characteristics of revised system include greatly increased speed, convenience, and reliability.

  9. Optical design using computer graphics.

    PubMed

    Howard, J M

    2001-07-01

    For decades the computer has been the primary tool used for optical design. Typical tasks include performing numerical calculations for ray tracing and analysis and rendering graphics for system drawings. As machines become faster with each new generation, the time needed for a particular design task has greatly reduced, allowing multiple assignments to be performed with little noticeable delay. This lets the designer modify a system and then immediately see the results rendered in graphics with a single motion. Such visual design methods are discussed here, where graphics of systems and plots relating to their performance are produced in real time, permitting the optical designer to design by pictures. Three examples are given: an educational tutorial for designing a simple microscope objective, an unobstructed reflective telescope composed of three spherical mirrors, and a modified Offner relay with an accessible pupil.

  10. The design and implementation of stereoscopic 3D scalable vector graphics based on WebKit

    NASA Astrophysics Data System (ADS)

    Liu, Zhongxin; Wang, Wenmin; Wang, Ronggang

    2014-03-01

    Scalable Vector Graphics (SVG), which is a language designed based on eXtensible Markup Language (XML), is used to describe basic shapes embedded in webpages, such as circles and rectangles. However, it can only depict 2D shapes. As a consequence, web pages using classical SVG can only display 2D shapes on a screen. With the increasing development of stereoscopic 3D (S3D) technology, binocular 3D devices have been widely used. Under this circumstance, we intend to extend the widely used web rendering engine WebKit to support the description and display of S3D webpages. Therefore, the extension of SVG is of necessity. In this paper, we will describe how to design and implement SVG shapes with stereoscopic 3D mode. Two attributes representing the depth and thickness are added to support S3D shapes. The elimination of hidden lines and hidden surfaces, which is an important process in this project, is described as well. The modification of WebKit is also discussed, which is made to support the generation of both left view and right view at the same time. As is shown in the result, in contrast to the 2D shapes generated by the Google Chrome web browser, the shapes got from our modified browser are in S3D mode. With the feeling of depth and thickness, the shapes seem to be real 3D objects away from the screen, rather than simple curves and lines as before.

  11. A Graphic Overlay Method for Selection of Osteotomy Site in Chronic Radial Head Dislocation: An Evaluation of 3D-printed Bone Models.

    PubMed

    Kim, Hui Taek; Ahn, Tae Young; Jang, Jae Hoon; Kim, Kang Hee; Lee, Sung Jae; Jung, Duk Young

    2017-03-01

    Three-dimensional (3D) computed tomography imaging is now being used to generate 3D models for planning orthopaedic surgery, but the process remains time consuming and expensive. For chronic radial head dislocation, we have designed a graphic overlay approach that employs selected 3D computer images and widely available software to simplify the process of osteotomy site selection. We studied 5 patients (2 traumatic and 3 congenital) with unilateral radial head dislocation. These patients were treated with surgery based on traditional radiographs, but they also had full sets of 3D CT imaging done both before and after their surgery: these 3D CT images form the basis for this study. From the 3D CT images, each patient generated 3 sets of 3D-printed bone models: 2 copies of the preoperative condition, and 1 copy of the postoperative condition. One set of the preoperative models was then actually osteotomized and fixed in the manner suggested by our graphic technique. Arcs of rotation of the 3 sets of 3D-printed bone models were then compared. Arcs of rotation of the 3 groups of bone models were significantly different, with the models osteotomized accordingly to our graphic technique having the widest arcs. For chronic radial head dislocation, our graphic overlay approach simplifies the selection of the osteotomy site(s). Three-dimensional-printed bone models suggest that this approach could improve range of motion of the forearm in actual surgical practice. Level IV-therapeutic study.

  12. Tools for computer graphics applications

    NASA Technical Reports Server (NTRS)

    Phillips, R. L.

    1976-01-01

    Extensive research in computer graphics has produced a collection of basic algorithms and procedures whose utility spans many disciplines. These tools are described in terms of their fundamental aspects, implementations, applications, and availability. Programs which are discussed include basic data plotting, curve smoothing, and depiction of three dimensional surfaces. As an aid to potential users of these tools, particular attention is given to discussing their availability and, where applicable, their cost.

  13. Trends in Continuity and Interpolation for Computer Graphics.

    PubMed

    Gonzalez Garcia, Francisco

    2015-01-01

    In every computer graphics oriented application today, it is a common practice to texture 3D models as a way to obtain realistic material. As part of this process, mesh texturing, deformation, and visualization are all key parts of the computer graphics field. This PhD dissertation was completed in the context of these three important and related fields in computer graphics. The article presents techniques that improve on existing state-of-the-art approaches related to continuity and interpolation in texture space (texturing), object space (deformation), and screen space (rendering).

  14. Computer Graphics for Multimedia and Hypermedia Development.

    ERIC Educational Resources Information Center

    Mohler, James L.

    1998-01-01

    Discusses several theoretical and technical aspects of computer-graphics development that are useful for creating hypermedia and multimedia materials. Topics addressed include primary bitmap attributes in computer graphics, the jigsaw principle, and raster layering. (MSE)

  15. Computer Graphics and Administrative Decision-Making.

    ERIC Educational Resources Information Center

    Yost, Michael

    1984-01-01

    Reduction in prices now makes it possible for almost any institution to use computer graphics for administrative decision making and research. Current and potential uses of computer graphics in these two areas are discussed. (JN)

  16. Appendage flow computations using the INS3D computer code

    NASA Astrophysics Data System (ADS)

    Ohring, Samuel

    1989-10-01

    The INS3D code, a steady state incompressible, fully 3-D Navier-Stokes solver, was applied to the computation of flow past an appendage mounted between two parallel flat plates of infinite extent at a Reynolds number of one-half million. The Baldwin-Lomax turbulence model was used to compute the eddy viscosity. The appendage consisted of a 1.5:1 elliptical nose and a NACA 0020 tail joined at maximum thickness of 0.24 chordlengths. A detailed description of the flow results covers all the major features of appendage flow and the results, for an unfilleted appendage, are in general agreement with experimental and other numerical results, except that the lateral location of the horseshoe vortex is larger than that in the experimental results. A detailed description is presented of the important trailing edge vortex. Detailed results for a second flow case, in which filleting is applied mainly to the front and side of the aforementioned appendage, show a greatly weakened horseshoe vortex but a still significant trailing edge vortex, that prevented velocity-deficit reduction in the wake, compared to the unfilleted appendage flow case. The calculations for the filleted case also exhibited an upstream instability. The plotting program PLOT3D was used to obtain color photos for flow visualization.

  17. Collection Of Software For Computer Graphics

    NASA Technical Reports Server (NTRS)

    Hibbard, Eric A.; Makatura, George

    1990-01-01

    Ames Research Graphics System (ARCGRAPH) collection of software libraries and software utilities assisting researchers in generating, manipulating, and visualizing graphical data. Defines metafile format containing device-independent graphical data. File format used with various computer-graphics-manipulation and -animation software packages at Ames, including SURF (COSMIC Program ARC-12381) and GAS (COSMIC Program ARC-12379). Consists of two-stage "pipeline" used to put out graphical primitives. ARCGRAPH libraries developed on VAX computer running VMS.

  18. CASTLE3D - A Computer Aided System for Labelling Archaeological Excavations in 3D

    NASA Astrophysics Data System (ADS)

    Houshiar, H.; Borrmann, D.; Elseberg, J.; Nüchter, A.; Näth, F.; Winkler, S.

    2015-08-01

    Documentation of archaeological excavation sites with conventional methods and tools such as hand drawings, measuring tape and archaeological notes is time consuming. This process is prone to human errors and the quality of the documentation depends on the qualification of the archaeologist on site. Use of modern technology and methods in 3D surveying and 3D robotics facilitate and improve this process. Computer-aided systems and databases improve the documentation quality and increase the speed of data acquisition. 3D laser scanning is the state of the art in modelling archaeological excavation sites, historical sites and even entire cities or landscapes. Modern laser scanners are capable of data acquisition of up to 1 million points per second. This provides a very detailed 3D point cloud of the environment. 3D point clouds and 3D models of an excavation site provide a better representation of the environment for the archaeologist and for documentation. The point cloud can be used both for further studies on the excavation and for the presentation of results. This paper introduces a Computer aided system for labelling archaeological excavations in 3D (CASTLE3D). Consisting of a set of tools for recording and georeferencing the 3D data from an excavation site, CASTLE3D is a novel documentation approach in industrial archaeology. It provides a 2D and 3D visualisation of the data and an easy-to-use interface that enables the archaeologist to select regions of interest and to interact with the data in both representations. The 2D visualisation and a 3D orthogonal view of the data provide cuts of the environment that resemble the traditional hand drawings. The 3D perspective view gives a realistic view of the environment. CASTLE3D is designed as an easy-to-use on-site semantic mapping tool for archaeologists. Each project contains a predefined set of semantic information that can be used to label findings in the data. Multiple regions of interest can be joined under

  19. Operational computer graphics in the flight dynamics environment

    NASA Technical Reports Server (NTRS)

    Jeletic, James F.

    1989-01-01

    Over the past five years, the Flight Dynamics Division of the National Aeronautics and Space Administration's (NASA's) Goddard Space Flight Center has incorporated computer graphics technology into its operational environment. In an attempt to increase the effectiveness and productivity of the Division, computer graphics software systems have been developed that display spacecraft tracking and telemetry data in 2-d and 3-d graphic formats that are more comprehensible than the alphanumeric tables of the past. These systems vary in functionality from real-time mission monitoring system, to mission planning utilities, to system development tools. Here, the capabilities and architecture of these systems are discussed.

  20. Computer-assisted information graphics from the graphic design perspective

    SciTech Connect

    Marcus, A.

    1983-11-01

    Computer-assisted information graphics can benefit by adopting some of the working processes, principles, and areas of concern typical of information-oriented graphic designers. A review of some basic design considerations is followed by a discussion of the creation and design of a prototype nonverbal narrative which combines symbols, charts, maps, and diagrams.

  1. Graphics and Flow Visualization of Computer Generated Flow Fields

    NASA Technical Reports Server (NTRS)

    Kathong, M.; Tiwari, S. N.

    1987-01-01

    Flow field variables are visualized using color representations described on surfaces that are interpolated from computational grids and transformed to digital images. Techniques for displaying two and three dimensional flow field solutions are addressed. The transformations and the use of an interactive graphics program for CFD flow field solutions, called PLOT3D, which runs on the color graphics IRIS workstation are described. An overview of the IRIS workstation is also described.

  2. Techniques for efficient, real-time, 3D visualization of multi-modality cardiac data using consumer graphics hardware.

    PubMed

    Levin, David; Aladl, Usaf; Germano, Guido; Slomka, Piotr

    2005-09-01

    We exploit consumer graphics hardware to perform real-time processing and visualization of high-resolution, 4D cardiac data. We have implemented real-time, realistic volume rendering, interactive 4D motion segmentation of cardiac data, visualization of multi-modality cardiac data and 3D display of multiple series cardiac MRI. We show that an ATI Radeon 9700 Pro can render a 512x512x128 cardiac Computed Tomography (CT) study at 0.9 to 60 frames per second (fps) depending on rendering parameters and that 4D motion based segmentation can be performed in real-time. We conclude that real-time rendering and processing of cardiac data can be implemented on consumer graphics cards.

  3. 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. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  4. Medical workstation design: enhancing graphical interface with 3D anatomical atlas

    NASA Astrophysics Data System (ADS)

    Hoo, Kent S., Jr.; Wong, Stephen T. C.; Grant, Ellen

    1997-05-01

    The huge data archive of the UCSF Hospital Integrated Picture Archiving and Communication System gives healthcare providers access to diverse kinds of images and text for diagnosis and patient management. Given the mass of information accessible, however, conventional graphical user interface (GUI) approach overwhelms the user with forms, menus, fields, lists, and other widgets and causes 'information overloading.' This article describes a new approach that complements the conventional GUI with 3D anatomical atlases and presents the usefulness of this approach with a clinical neuroimaging application.

  5. A High Performance VLSI Computer Architecture For Computer Graphics

    NASA Astrophysics Data System (ADS)

    Chin, Chi-Yuan; Lin, Wen-Tai

    1988-10-01

    A VLSI computer architecture, consisting of multiple processors, is presented in this paper to satisfy the modern computer graphics demands, e.g. high resolution, realistic animation, real-time display etc.. All processors share a global memory which are partitioned into multiple banks. Through a crossbar network, data from one memory bank can be broadcasted to many processors. Processors are physically interconnected through a hyper-crossbar network (a crossbar-like network). By programming the network, the topology of communication links among processors can be reconfigurated to satisfy specific dataflows of different applications. Each processor consists of a controller, arithmetic operators, local memory, a local crossbar network, and I/O ports to communicate with other processors, memory banks, and a system controller. Operations in each processor are characterized into two modes, i.e. object domain and space domain, to fully utilize the data-independency characteristics of graphics processing. Special graphics features such as 3D-to-2D conversion, shadow generation, texturing, and reflection, can be easily handled. With the current high density interconnection (MI) technology, it is feasible to implement a 64-processor system to achieve 2.5 billion operations per second, a performance needed in most advanced graphics applications.

  6. Computer graphics for quality assurance

    NASA Astrophysics Data System (ADS)

    Gott, V. W.

    1982-01-01

    The use of CAD/CAM for quality assurance at Northrop is examined. The use of on-line and library computer graphics systems by the quality assurance personnel enabled the programming of lofting for at-will retrieval. The data is used to inspect master tools check features, castings, forgings, parts with basic moldline features, drawings, and tool design drawings. Lofting requests are made if the files are found to have inadequacies, and quality assurance findings are returned to the requester in hard copy form. Continuous updating of the system is reviewed, and the relevant data for cataloguing and identifying parts and parts surfaces are outlined. A reduction of time spent in inspections of 400% has been achieved with the system.

  7. ElectroEncephaloGraphics: Making waves in computer graphics research.

    PubMed

    Mustafa, Maryam; Magnor, Marcus

    2014-01-01

    Electroencephalography (EEG) is a novel modality for investigating perceptual graphics problems. Until recently, EEG has predominantly been used for clinical diagnosis, in psychology, and by the brain-computer-interface community. Researchers are extending it to help understand the perception of visual output from graphics applications and to create approaches based on direct neural feedback. Researchers have applied EEG to graphics to determine perceived image and video quality by detecting typical rendering artifacts, to evaluate visualization effectiveness by calculating the cognitive load, and to automatically optimize rendering parameters for images and videos on the basis of implicit neural feedback.

  8. Is There Computer Graphics after Multimedia?

    ERIC Educational Resources Information Center

    Booth, Kellogg S.

    Computer graphics has been driven by the desire to generate real-time imagery subject to constraints imposed by the human visual system. The future of computer graphics, when off-the-shelf systems have full multimedia capability and when standard computing engines render imagery faster than real-time, remains to be seen. A dedicated pipeline for…

  9. Computer Graphics in ChE Education.

    ERIC Educational Resources Information Center

    Reklaitis, G. V.; And Others

    1983-01-01

    Examines current uses and future possibilities of computer graphics in chemical engineering, discussing equipment needs, maintenance/manpower costs, and plan to implement computer graphics into existing programs. The plan involves matching fund equipment grants, grants for development of computer assisted instructional (CAI) software, chemical…

  10. Computer Graphics in ChE Education.

    ERIC Educational Resources Information Center

    Reklaitis, G. V.; And Others

    1983-01-01

    Examines current uses and future possibilities of computer graphics in chemical engineering, discussing equipment needs, maintenance/manpower costs, and plan to implement computer graphics into existing programs. The plan involves matching fund equipment grants, grants for development of computer assisted instructional (CAI) software, chemical…

  11. Assessment of 3D Viewers for the Display of Interactive Documents in the Learning of Graphic Engineering

    ERIC Educational Resources Information Center

    Barbero, Basilio Ramos; Pedrosa, Carlos Melgosa; Mate, Esteban Garcia

    2012-01-01

    The purpose of this study is to determine which 3D viewers should be used for the display of interactive graphic engineering documents, so that the visualization and manipulation of 3D models provide useful support to students of industrial engineering (mechanical, organizational, electronic engineering, etc). The technical features of 26 3D…

  12. Assessment of 3D Viewers for the Display of Interactive Documents in the Learning of Graphic Engineering

    ERIC Educational Resources Information Center

    Barbero, Basilio Ramos; Pedrosa, Carlos Melgosa; Mate, Esteban Garcia

    2012-01-01

    The purpose of this study is to determine which 3D viewers should be used for the display of interactive graphic engineering documents, so that the visualization and manipulation of 3D models provide useful support to students of industrial engineering (mechanical, organizational, electronic engineering, etc). The technical features of 26 3D…

  13. Computer Series, 3: Computer Graphics for Chemical Education.

    ERIC Educational Resources Information Center

    Soltzberg, Leonard J.

    1979-01-01

    Surveys the current scene in computer graphics from the point of view of a chemistry educator. Discusses the scope of current applications of computer graphics in chemical education, and provides information about hardware and software systems to promote communication with vendors of computer graphics equipment. (HM)

  14. A graphic user interface for efficient 3D photo-reconstruction based on free software

    NASA Astrophysics Data System (ADS)

    Castillo, Carlos; James, Michael; Gómez, Jose A.

    2015-04-01

    Recently, different studies have stressed the applicability of 3D photo-reconstruction based on Structure from Motion algorithms in a wide range of geoscience applications. For the purpose of image photo-reconstruction, a number of commercial and freely available software packages have been developed (e.g. Agisoft Photoscan, VisualSFM). The workflow involves typically different stages such as image matching, sparse and dense photo-reconstruction, point cloud filtering and georeferencing. For approaches using open and free software, each of these stages usually require different applications. In this communication, we present an easy-to-use graphic user interface (GUI) developed in Matlab® code as a tool for efficient 3D photo-reconstruction making use of powerful existing software: VisualSFM (Wu, 2015) for photo-reconstruction and CloudCompare (Girardeau-Montaut, 2015) for point cloud processing. The GUI performs as a manager of configurations and algorithms, taking advantage of the command line modes of existing software, which allows an intuitive and automated processing workflow for the geoscience user. The GUI includes several additional features: a) a routine for significantly reducing the duration of the image matching operation, normally the most time consuming stage; b) graphical outputs for understanding the overall performance of the algorithm (e.g. camera connectivity, point cloud density); c) a number of useful options typically performed before and after the photo-reconstruction stage (e.g. removal of blurry images, image renaming, vegetation filtering); d) a manager of batch processing for the automated reconstruction of different image datasets. In this study we explore the advantages of this new tool by testing its performance using imagery collected in several soil erosion applications. References Girardeau-Montaut, D. 2015. CloudCompare documentation accessed at http://cloudcompare.org/ Wu, C. 2015. VisualSFM documentation access at http://ccwu.me/vsfm/doc.html#.

  15. Novel fully integrated computer system for custom footwear: from 3D digitization to manufacturing

    NASA Astrophysics Data System (ADS)

    Houle, Pascal-Simon; Beaulieu, Eric; Liu, Zhaoheng

    1998-03-01

    This paper presents a recently developed custom footwear system, which integrates 3D digitization technology, range image fusion techniques, a 3D graphical environment for corrective actions, parametric curved surface representation and computer numerical control (CNC) machining. In this system, a support designed with the help of biomechanics experts can stabilize the foot in a correct and neutral position. The foot surface is then captured by a 3D camera using active ranging techniques. A software using a library of documented foot pathologies suggests corrective actions on the orthosis. Three kinds of deformations can be achieved. The first method uses previously scanned pad surfaces by our 3D scanner, which can be easily mapped onto the foot surface to locally modify the surface shape. The second kind of deformation is construction of B-Spline surfaces by manipulating control points and modifying knot vectors in a 3D graphical environment to build desired deformation. The last one is a manual electronic 3D pen, which may be of different shapes and sizes, and has an adjustable 'pressure' information. All applied deformations should respect a G1 surface continuity, which ensure that the surface can accustom a foot. Once the surface modification process is completed, the resulting data is sent to manufacturing software for CNC machining.

  16. Applications of computer graphics to aircraft synthesis

    NASA Technical Reports Server (NTRS)

    Carmichael, R. L.; Putnam, R.

    1975-01-01

    The history of the development of an aircraft configuration synthesis program using interactive computer graphics was described. A system based on time-sharing was compared to two different concepts based on distributed computing.

  17. Some Recent Advances in Computer Graphics.

    ERIC Educational Resources Information Center

    Whitted, Turner

    1982-01-01

    General principles of computer graphics are reviewed, including discussions of display hardware, geometric modeling, algorithms, and applications in science, computer-aided design, flight training, communications, business, art, and entertainment. (JN)

  18. Multitasking the code ARC3D. [for computational fluid dynamics

    NASA Technical Reports Server (NTRS)

    Barton, John T.; Hsiung, Christopher C.

    1986-01-01

    The CRAY multitasking system was developed in order to utilize all four processors and sharply reduce the wall clock run time. This paper describes the techniques used to modify the computational fluid dynamics code ARC3D for this run and analyzes the achieved speedup. The ARC3D code solves either the Euler or thin-layer N-S equations using an implicit approximate factorization scheme. Results indicate that multitask processing can be used to achieve wall clock speedup factors of over three times, depending on the nature of the program code being used. Multitasking appears to be particularly advantageous for large-memory problems running on multiple CPU computers.

  19. Image quality enhancement and computation acceleration of 3D holographic display using a symmetrical 3D GS algorithm.

    PubMed

    Zhou, Pengcheng; Bi, Yong; Sun, Minyuan; Wang, Hao; Li, Fang; Qi, Yan

    2014-09-20

    The 3D Gerchberg-Saxton (GS) algorithm can be used to compute a computer-generated hologram (CGH) to produce a 3D holographic display. But, using the 3D GS method, there exists a serious distortion in reconstructions of binary input images. We have eliminated the distortion and improved the image quality of the reconstructions by a maximum of 486%, using a symmetrical 3D GS algorithm that is developed based on a traditional 3D GS algorithm. In addition, the hologram computation speed has been accelerated by 9.28 times, which is significant for real-time holographic displays.

  20. 3D measurement system based on computer-generated gratings

    NASA Astrophysics Data System (ADS)

    Zhu, Yongjian; Pan, Weiqing; Luo, Yanliang

    2010-08-01

    A new kind of 3D measurement system has been developed to achieve the 3D profile of complex object. The principle of measurement system is based on the triangular measurement of digital fringe projection, and the fringes are fully generated from computer. Thus the computer-generated four fringes form the data source of phase-shifting 3D profilometry. The hardware of system includes the computer, video camera, projector, image grabber, and VGA board with two ports (one port links to the screen, another to the projector). The software of system consists of grating projection module, image grabbing module, phase reconstructing module and 3D display module. A software-based synchronizing method between grating projection and image capture is proposed. As for the nonlinear error of captured fringes, a compensating method is introduced based on the pixel-to-pixel gray correction. At the same time, a least square phase unwrapping is used to solve the problem of phase reconstruction by using the combination of Log Modulation Amplitude and Phase Derivative Variance (LMAPDV) as weight. The system adopts an algorithm from Matlab Tool Box for camera calibration. The 3D measurement system has an accuracy of 0.05mm. The execution time of system is 3~5s for one-time measurement.

  1. 3D graphics, virtual reality, and motion-onset visual evoked potentials in neurogaming.

    PubMed

    Beveridge, R; Wilson, S; Coyle, D

    2016-01-01

    A brain-computer interface (BCI) offers movement-free control of a computer application and is achieved by reading and translating the cortical activity of the brain into semantic control signals. Motion-onset visual evoked potentials (mVEP) are neural potentials employed in BCIs and occur when motion-related stimuli are attended visually. mVEP dynamics are correlated with the position and timing of the moving stimuli. To investigate the feasibility of utilizing the mVEP paradigm with video games of various graphical complexities including those of commercial quality, we conducted three studies over four separate sessions comparing the performance of classifying five mVEP responses with variations in graphical complexity and style, in-game distractions, and display parameters surrounding mVEP stimuli. To investigate the feasibility of utilizing contemporary presentation modalities in neurogaming, one of the studies compared mVEP classification performance when stimuli were presented using the oculus rift virtual reality headset. Results from 31 independent subjects were analyzed offline. The results show classification performances ranging up to 90% with variations in conditions in graphical complexity having limited effect on mVEP performance; thus, demonstrating the feasibility of using the mVEP paradigm within BCI-based neurogaming.

  2. Getting the picture through computer graphics

    NASA Technical Reports Server (NTRS)

    Gregory, T. J.; Carmichael, R. L.

    1983-01-01

    The benefits of computer graphics in design are discussed, with particular reference to aerospace applications. The evolution of computer graphics is illustrated by the following examples: solid lines representing the edges of solid geometric parts; graphics with colored lines providing better descriptions of a variety of objects, such as circuit boards, maps, and complete aircraft; graphics with colored surfaces mapping such information as heating rates and pressures on aircraft; and color mapping combined with shading. Finally, examples are given of complex flow fields and scenes showing many objects that are displayed dynamically, with transparency used to clarify these scenes.

  3. The 3-D inelastic analyses for computational structural mechanics

    NASA Technical Reports Server (NTRS)

    Hopkins, D. A.; Chamis, C. C.

    1989-01-01

    The 3-D inelastic analysis method is a focused program with the objective to develop computationally effective analysis methods and attendant computer codes for three-dimensional, nonlinear time and temperature dependent problems present in the hot section of turbojet engine structures. Development of these methods was a major part of the Hot Section Technology (HOST) program over the past five years at Lewis Research Center.

  4. A System for Generating Instructional Computer Graphics.

    ERIC Educational Resources Information Center

    Nygard, Kendall E.; Ranganathan, Babusankar

    1983-01-01

    Description of the Tektronix-Based Interactive Graphics System for Instruction (TIGSI), which was developed for generating graphics displays in computer-assisted instruction materials, discusses several applications (e.g., reinforcing learning of concepts, principles, rules, and problem-solving techniques) and presents advantages of the TIGSI…

  5. A Sporting Look at Computer Graphics.

    ERIC Educational Resources Information Center

    Mattson, Merry B.

    1984-01-01

    Suggests having students design a football field (looking at it from above) as the final project of a unit on computer graphics. Includes listings for 13 short Applesoft programs (involving LO- and HI-RES graphics) which students can use in making the field. Advanced students can use the animation techniques. (JN)

  6. FUN3D and CFL3D Computations for the First High Lift Prediction Workshop

    NASA Technical Reports Server (NTRS)

    Park, Michael A.; Lee-Rausch, Elizabeth M.; Rumsey, Christopher L.

    2011-01-01

    Two Reynolds-averaged Navier-Stokes codes were used to compute flow over the NASA Trapezoidal Wing at high lift conditions for the 1st AIAA CFD High Lift Prediction Workshop, held in Chicago in June 2010. The unstructured-grid code FUN3D and the structured-grid code CFL3D were applied to several different grid systems. The effects of code, grid system, turbulence model, viscous term treatment, and brackets were studied. The SST model on this configuration predicted lower lift than the Spalart-Allmaras model at high angles of attack; the Spalart-Allmaras model agreed better with experiment. Neglecting viscous cross-derivative terms caused poorer prediction in the wing tip vortex region. Output-based grid adaptation was applied to the unstructured-grid solutions. The adapted grids better resolved wake structures and reduced flap flow separation, which was also observed in uniform grid refinement studies. Limitations of the adaptation method as well as areas for future improvement were identified.

  7. A graphical user interface for calculation of 3D dose distribution using Monte Carlo simulations

    NASA Astrophysics Data System (ADS)

    Chow, J. C. L.; Leung, M. K. K.

    2008-02-01

    A software graphical user interface (GUI) for calculation of 3D dose distribution using Monte Carlo (MC) simulation is developed using MATLAB. This GUI (DOSCTP) provides a user-friendly platform for DICOM CT-based dose calculation using EGSnrcMP-based DOSXYZnrc code. It offers numerous features not found in DOSXYZnrc, such as the ability to use multiple beams from different phase-space files, and has built-in dose analysis and visualization tools. DOSCTP is written completely in MATLAB, with integrated access to DOSXYZnrc and CTCREATE. The program function may be divided into four subgroups, namely, beam placement, MC simulation with DOSXYZnrc, dose visualization, and export. Each is controlled by separate routines. The verification of DOSCTP was carried out by comparing plans with different beam arrangements (multi-beam/photon arc) on an inhomogeneous phantom as well as patient CT between the GUI and Pinnacle3. DOSCTP was developed and verified with the following features: (1) a built-in voxel editor to modify CT-based DOSXYZnrc phantoms for research purposes; (2) multi-beam placement is possible, which cannot be achieved using the current DOSXYZnrc code; (3) the treatment plan, including the dose distributions, contours and image set can be exported to a commercial treatment planning system such as Pinnacle3 or to CERR using RTOG format for plan evaluation and comparison; (4) a built-in RTOG-compatible dose reviewer for dose visualization and analysis such as finding the volume of hot/cold spots in the 3D dose distributions based on a user threshold. DOSCTP greatly simplifies the use of DOSXYZnrc and CTCREATE, and offers numerous features that not found in the original user-code. Moreover, since phase-space beams can be defined and generated by the user, it is a particularly useful tool to carry out plans using specifically designed irradiators/accelerators that cannot be found in the Linac library of commercial treatment planning systems.

  8. Astronomy Simulation with Computer Graphics.

    ERIC Educational Resources Information Center

    Thomas, William E.

    1982-01-01

    "Planetary Motion Simulations" is a system of programs designed for students to observe motions of a superior planet (one whose orbit lies outside the orbit of the earth). Programs run on the Apple II microcomputer and employ high-resolution graphics to present the motions of Saturn. (Author/JN)

  9. Computational model of stereoscopic 3D visual saliency.

    PubMed

    Wang, Junle; Da Silva, Matthieu Perreira; Le Callet, Patrick; Ricordel, Vincent

    2013-06-01

    Many computational models of visual attention performing well in predicting salient areas of 2D images have been proposed in the literature. The emerging applications of stereoscopic 3D display bring an additional depth of information affecting the human viewing behavior, and require extensions of the efforts made in 2D visual modeling. In this paper, we propose a new computational model of visual attention for stereoscopic 3D still images. Apart from detecting salient areas based on 2D visual features, the proposed model takes depth as an additional visual dimension. The measure of depth saliency is derived from the eye movement data obtained from an eye-tracking experiment using synthetic stimuli. Two different ways of integrating depth information in the modeling of 3D visual attention are then proposed and examined. For the performance evaluation of 3D visual attention models, we have created an eye-tracking database, which contains stereoscopic images of natural content and is publicly available, along with this paper. The proposed model gives a good performance, compared to that of state-of-the-art 2D models on 2D images. The results also suggest that a better performance is obtained when depth information is taken into account through the creation of a depth saliency map, rather than when it is integrated by a weighting method.

  10. NASA's 3D Flight Computer for Space Applications

    NASA Technical Reports Server (NTRS)

    Alkalai, Leon

    2000-01-01

    The New Millennium Program (NMP) Integrated Product Development Team (IPDT) for Microelectronics Systems was planning to validate a newly developed 3D Flight Computer system on its first deep-space flight, DS1, launched in October 1998. This computer, developed in the 1995-97 time frame, contains many new computer technologies previously never used in deep-space systems. They include: advanced 3D packaging architecture for future low-mass and low-volume avionics systems; high-density 3D packaged chip-stacks for both volatile and non-volatile mass memory: 400 Mbytes of local DRAM memory, and 128 Mbytes of Flash memory; high-bandwidth Peripheral Component Interface (Per) local-bus with a bridge to VME; high-bandwidth (20 Mbps) fiber-optic serial bus; and other attributes, such as standard support for Design for Testability (DFT). Even though this computer system did not complete on time for delivery to the DS1 project, it was an important development along a technology roadmap towards highly integrated and highly miniaturized avionics systems for deep-space applications. This continued technology development is now being performed by NASA's Deep Space System Development Program (also known as X2000) and within JPL's Center for Integrated Space Microsystems (CISM).

  11. Phast4Windows: A 3D graphical user interface for the reactive-transport simulator PHAST

    USGS Publications Warehouse

    Charlton, Scott R.; Parkhurst, David L.

    2013-01-01

    Phast4Windows is a Windows® program for developing and running groundwater-flow and reactive-transport models with the PHAST simulator. This graphical user interface allows definition of grid-independent spatial distributions of model properties—the porous media properties, the initial head and chemistry conditions, boundary conditions, and locations of wells, rivers, drains, and accounting zones—and other parameters necessary for a simulation. Spatial data can be defined without reference to a grid by drawing, by point-by-point definitions, or by importing files, including ArcInfo® shape and raster files. All definitions can be inspected, edited, deleted, moved, copied, and switched from hidden to visible through the data tree of the interface. Model features are visualized in the main panel of the interface, so that it is possible to zoom, pan, and rotate features in three dimensions (3D). PHAST simulates single phase, constant density, saturated groundwater flow under confined or unconfined conditions. Reactions among multiple solutes include mineral equilibria, cation exchange, surface complexation, solid solutions, and general kinetic reactions. The interface can be used to develop and run simple or complex models, and is ideal for use in the classroom, for analysis of laboratory column experiments, and for development of field-scale simulations of geochemical processes and contaminant transport.

  12. Advanced computational tools for 3-D seismic analysis

    SciTech Connect

    Barhen, J.; Glover, C.W.; Protopopescu, V.A.

    1996-06-01

    The global objective of this effort is to develop advanced computational tools for 3-D seismic analysis, and test the products using a model dataset developed under the joint aegis of the United States` Society of Exploration Geophysicists (SEG) and the European Association of Exploration Geophysicists (EAEG). The goal is to enhance the value to the oil industry of the SEG/EAEG modeling project, carried out with US Department of Energy (DOE) funding in FY` 93-95. The primary objective of the ORNL Center for Engineering Systems Advanced Research (CESAR) is to spearhead the computational innovations techniques that would enable a revolutionary advance in 3-D seismic analysis. The CESAR effort is carried out in collaboration with world-class domain experts from leading universities, and in close coordination with other national laboratories and oil industry partners.

  13. Computational issues connected with 3D N-body simulations

    NASA Astrophysics Data System (ADS)

    Pfenniger, D.; Friedli, D.

    1993-03-01

    Computational problems related to modeling gravitational systems, and running and analyzing 3D N-body models are discussed. N-body simulations using Particle-Mesh techniques with polar grids are especially well-suited, and physically justified, when studying quiet evolutionary processes in disk galaxies. This technique allows large N, high central resolution, and is still the fastest one. Regardless of the method chosen to compute gravitation, softening is a compromise between HF amplification and resolution. Softened spherical and ellipsoidal kernels with variable resolution are set up. Detailed characteristics of the 3D polar grid, tests, code performances, and vectorization rates are also given. For integrating motion in rotating coordinates, a stable symplectic extension of the leap-frog algorithm is described. The technique used to search for periodic orbits in arbitrary N-body potentials and to determine their stability is explained.

  14. A Prototype Educational Model for Hepatobiliary Interventions: Unveiling the Role of Graphic Designers in Medical 3D Printing.

    PubMed

    Javan, Ramin; Zeman, Merissa N

    2017-08-14

    In the context of medical three-dimensional (3D) printing, in addition to 3D reconstruction from cross-sectional imaging, graphic design plays a role in developing and/or enhancing 3D-printed models. A custom prototype modular 3D model of the liver was graphically designed depicting segmental anatomy of the parenchyma containing color-coded hepatic vasculature and biliary tree. Subsequently, 3D printing was performed using transparent resin for the surface of the liver and polyamide material to develop hollow internal structures that allow for passage of catheters and wires. A number of concepts were incorporated into the model. A representative mass with surrounding feeding arterial supply was embedded to demonstrate tumor embolization. A straight narrow hollow tract connecting the mass to the surface of the liver, displaying the path of a biopsy device's needle, and the concept of needle "throw" length was designed. A connection between the middle hepatic and right portal veins was created to demonstrate transjugular intrahepatic portosystemic shunt (TIPS) placement. A hollow amorphous structure representing an abscess was created to allow the demonstration of drainage catheter placement with the formation of pigtail tip. Percutaneous biliary drain and cholecystostomy tube placement were also represented. The skills of graphic designers may be utilized in creating highly customized 3D-printed models. A model was developed for the demonstration and simulation of multiple hepatobiliary interventions, for training purposes, patient counseling and consenting, and as a prototype for future development of a functioning interventional phantom.

  15. Comfort constrains graphic workspace: test results of a 3D forearm model.

    PubMed

    Schillings, J J; Thomassen, A J; Meulenbroek, R G

    2000-01-01

    Human movement performance is subject to many physical and psychological constraints. Analyses of these constraints may not only improve our understanding of the performance aspects that subjects need to keep under continuous control, but may also shed light on the possible origins of specific behavioral preferences that people display in motor tasks. The goal of the present paper is to make an empirical contribution here. In a recent simulation study, we reported effects of pen-grip and forearm-posture constraints on the spatial characteristics of the pen tip's workspace in drawing. The effects concerned changes in the location, size, and orientation of the reachable part of the writing plane, as well as variations in the computed degree of comfort in the hand and finger postures required to reach the various parts of this area. The present study is aimed at empirically evaluating to what extent these effects influence subjects' graphic behavior in a simple, free line-drawing task. The task involved the production of small back-and-forth drawing movements in various directions, to be chosen randomly under three forearm-posture and five pen-grip conditions. The observed variations in the subjects' choice of starting positions showed a high level of agreement with those of the simulated graphic-area locations, showing that biomechanically defined comfort of starting postures is indeed a determinant of the selection of starting points. Furthermore, between-condition rotations in the frequency distributions of the realized stroke directions corresponded to the simulation results, which again confirms the importance of comfort in directional preferences. It is concluded that postural rather than spatial constraints primarily affect subjects' preferences for starting positions and stroke directions in graphic motor performance. The relevance of the present modelling approach and its results for the broader field of complex motor behavior, including the manipulation of

  16. Development of a computer controlled 3-d braiding machine

    SciTech Connect

    Yan Jianhua; Li Jialu

    1994-12-31

    This paper deals with development of a large size, multiuse, controlled 3-D cartesian grid braiding machine, its function and application. The 180 column and 120 tracks, the flexible and low power consuming driving system, the error detector systems and the computer controlling system are the major parts of the machine. The machine can produce wide variety of size. shape and pattern of fabrics and can also produce several fabrics at a time.

  17. Noninvasive computational imaging of cardiac electrophysiology for 3-D infarct.

    PubMed

    Wang, Linwei; Wong, Ken C L; Zhang, Heye; Liu, Huafeng; Shi, Pengcheng

    2011-04-01

    Myocardial infarction (MI) creates electrophysiologically altered substrates that are responsible for ventricular arrhythmias, such as tachycardia and fibrillation. The presence, size, location, and composition of infarct scar bear significant prognostic and therapeutic implications for individual subjects. We have developed a statistical physiological model-constrained framework that uses noninvasive body-surface-potential data and tomographic images to estimate subject-specific transmembrane-potential (TMP) dynamics inside the 3-D myocardium. In this paper, we adapt this framework for the purpose of noninvasive imaging, detection, and quantification of 3-D scar mass for postMI patients: the framework requires no prior knowledge of MI and converges to final subject-specific TMP estimates after several passes of estimation with intermediate feedback; based on the primary features of the estimated spatiotemporal TMP dynamics, we provide 3-D imaging of scar tissue and quantitative evaluation of scar location and extent. Phantom experiments were performed on a computational model of realistic heart-torso geometry, considering 87 transmural infarct scars of different sizes and locations inside the myocardium, and 12 compact infarct scars (extent between 10% and 30%) at different transmural depths. Real-data experiments were carried out on BSP and magnetic resonance imaging (MRI) data from four postMI patients, validated by gold standards and existing results. This framework shows unique advantage of noninvasive, quantitative, computational imaging of subject-specific TMP dynamics and infarct mass of the 3-D myocardium, with the potential to reflect details in the spatial structure and tissue composition/heterogeneity of 3-D infarct scar.

  18. Animation graphic interface for the space shuttle onboard computer

    NASA Technical Reports Server (NTRS)

    Wike, Jeffrey; Griffith, Paul

    1989-01-01

    Graphics interfaces designed to operate on space qualified hardware challenge software designers to display complex information under processing power and physical size constraints. Under contract to Johnson Space Center, MICROEXPERT Systems is currently constructing an intelligent interface for the LASER DOCKING SENSOR (LDS) flight experiment. Part of this interface is a graphic animation display for Rendezvous and Proximity Operations. The displays have been designed in consultation with Shuttle astronauts. The displays show multiple views of a satellite relative to the shuttle, coupled with numeric attitude information. The graphics are generated using position data received by the Shuttle Payload and General Support Computer (PGSC) from the Laser Docking Sensor. Some of the design considerations include crew member preferences in graphic data representation, single versus multiple window displays, mission tailoring of graphic displays, realistic 3D images versus generic icon representations of real objects, the physical relationship of the observers to the graphic display, how numeric or textual information should interface with graphic data, in what frame of reference objects should be portrayed, recognizing conditions of display information-overload, and screen format and placement consistency.

  19. Majority logic gate for 3D magnetic computing.

    PubMed

    Eichwald, Irina; Breitkreutz, Stephan; Ziemys, Grazvydas; Csaba, György; Porod, Wolfgang; Becherer, Markus

    2014-08-22

    For decades now, microelectronic circuits have been exclusively built from transistors. An alternative way is to use nano-scaled magnets for the realization of digital circuits. This technology, known as nanomagnetic logic (NML), may offer significant improvements in terms of power consumption and integration densities. Further advantages of NML are: non-volatility, radiation hardness, and operation at room temperature. Recent research focuses on the three-dimensional (3D) integration of nanomagnets. Here we show, for the first time, a 3D programmable magnetic logic gate. Its computing operation is based on physically field-interacting nanometer-scaled magnets arranged in a 3D manner. The magnets possess a bistable magnetization state representing the Boolean logic states '0' and '1.' Magneto-optical and magnetic force microscopy measurements prove the correct operation of the gate over many computing cycles. Furthermore, micromagnetic simulations confirm the correct functionality of the gate even for a size in the nanometer-domain. The presented device demonstrates the potential of NML for three-dimensional digital computing, enabling the highest integration densities.

  20. Low Cost Computer Graphics in Engineering Education.

    ERIC Educational Resources Information Center

    Phillips, Richard L.

    1981-01-01

    An evaluation of a personal computer was conducted to determine its potential for applications normally assumed to require higher resolution, higher cost graphics devices. Its resolution, stand-alone computing power, and capability to function as a distributed computing element in a time-sharing system are discussed. Six references are listed.…

  1. [Graphic assessment of retinal findings by computer].

    PubMed

    Effert, R; Wilberts, T; Reim, M

    1989-01-01

    Despite the increasing amount of patient data in the area of words and numbers that is being stored by computer, the graphic storage of ophthalmological findings has found only limited success. However, a sketch is much more instructive than a description in words. This paper shows that by using a suitable computer with a graphic oriented disc-operating system and a purchasable graphic and data base program, it is easily possible to generate sketches of retinal detachment on a computer screen. In the graphic program, all of the necessary symbols are already available when the program is started. The user just makes a copy of the symbols he needs to "draw" the actual fundus findings. We use the system of Meyer-Schwickerath. Afterwards, the drawing on the monitor is transferred into the data base program and stored.

  2. Tools for 3D scientific visualization in computational aerodynamics

    NASA Technical Reports Server (NTRS)

    Bancroft, Gordon; Plessel, Todd; Merritt, Fergus; Watson, Val

    1989-01-01

    The purpose is to describe the tools and techniques in use at the NASA Ames Research Center for performing visualization of computational aerodynamics, for example visualization of flow fields from computer simulations of fluid dynamics about vehicles such as the Space Shuttle. The hardware used for visualization is a high-performance graphics workstation connected to a super computer with a high speed channel. At present, the workstation is a Silicon Graphics IRIS 3130, the supercomputer is a CRAY2, and the high speed channel is a hyperchannel. The three techniques used for visualization are post-processing, tracking, and steering. Post-processing analysis is done after the simulation. Tracking analysis is done during a simulation but is not interactive, whereas steering analysis involves modifying the simulation interactively during the simulation. Using post-processing methods, a flow simulation is executed on a supercomputer and, after the simulation is complete, the results of the simulation are processed for viewing. The software in use and under development at NASA Ames Research Center for performing these types of tasks in computational aerodynamics is described. Workstation performance issues, benchmarking, and high-performance networks for this purpose are also discussed as well as descriptions of other hardware for digital video and film recording.

  3. Computational Challenges of 3D Radiative Transfer in Atmospheric Models

    NASA Astrophysics Data System (ADS)

    Jakub, Fabian; Bernhard, Mayer

    2017-04-01

    The computation of radiative heating and cooling rates is one of the most expensive components in todays atmospheric models. The high computational cost stems not only from the laborious integration over a wide range of the electromagnetic spectrum but also from the fact that solving the integro-differential radiative transfer equation for monochromatic light is already rather involved. This lead to the advent of numerous approximations and parameterizations to reduce the cost of the solver. One of the most prominent one is the so called independent pixel approximations (IPA) where horizontal energy transfer is neglected whatsoever and radiation may only propagate in the vertical direction (1D). Recent studies implicate that the IPA introduces significant errors in high resolution simulations and affects the evolution and development of convective systems. However, using fully 3D solvers such as for example MonteCarlo methods is not even on state of the art supercomputers feasible. The parallelization of atmospheric models is often realized by a horizontal domain decomposition, and hence, horizontal transfer of energy necessitates communication. E.g. a cloud's shadow at a low zenith angle will cast a long shadow and potentially needs to communication through a multitude of processors. Especially light in the solar spectral range may travel long distances through the atmosphere. Concerning highly parallel simulations, it is vital that 3D radiative transfer solvers put a special emphasis on parallel scalability. We will present an introduction to intricacies computing 3D radiative heating and cooling rates as well as report on the parallel performance of the TenStream solver. The TenStream is a 3D radiative transfer solver using the PETSc framework to iteratively solve a set of partial differential equation. We investigate two matrix preconditioners, (a) geometric algebraic multigrid preconditioning(MG+GAMG) and (b) block Jacobi incomplete LU (ILU) factorization. The

  4. Graphics supercomputer for computational fluid dynamics research

    NASA Astrophysics Data System (ADS)

    Liaw, Goang S.

    1994-11-01

    The objective of this project is to purchase a state-of-the-art graphics supercomputer to improve the Computational Fluid Dynamics (CFD) research capability at Alabama A & M University (AAMU) and to support the Air Force research projects. A cutting-edge graphics supercomputer system, Onyx VTX, from Silicon Graphics Computer Systems (SGI), was purchased and installed. Other equipment including a desktop personal computer, PC-486 DX2 with a built-in 10-BaseT Ethernet card, a 10-BaseT hub, an Apple Laser Printer Select 360, and a notebook computer from Zenith were also purchased. A reading room has been converted to a research computer lab by adding some furniture and an air conditioning unit in order to provide an appropriate working environments for researchers and the purchase equipment. All the purchased equipment were successfully installed and are fully functional. Several research projects, including two existing Air Force projects, are being performed using these facilities.

  5. Effectiveness of Applying 2D Static Depictions and 3D Animations to Orthographic Views Learning in Graphical Course

    ERIC Educational Resources Information Center

    Wu, Chih-Fu; Chiang, Ming-Chin

    2013-01-01

    This study provides experiment results as an educational reference for instructors to help student obtain a better way to learn orthographic views in graphical course. A visual experiment was held to explore the comprehensive differences between 2D static and 3D animation object features; the goal was to reduce the possible misunderstanding…

  6. Effectiveness of Applying 2D Static Depictions and 3D Animations to Orthographic Views Learning in Graphical Course

    ERIC Educational Resources Information Center

    Wu, Chih-Fu; Chiang, Ming-Chin

    2013-01-01

    This study provides experiment results as an educational reference for instructors to help student obtain a better way to learn orthographic views in graphical course. A visual experiment was held to explore the comprehensive differences between 2D static and 3D animation object features; the goal was to reduce the possible misunderstanding…

  7. Spatial Reasoning and 3D Graphics: A Study of GeoWall-Enhanced Astronomy Instruction

    NASA Astrophysics Data System (ADS)

    Turner, N. E.; Hegarty, M.; Martinez, L. E.

    2006-12-01

    One persistent difficulty many science students face is a lack of accurate, easily manipulated, 3-dimensional mental models of the systems they study. In Introductory Astronomy, students have difficulty conceptualizing the Sun-Earth-Moon system and the geometric relationships that cause the cycle of lunar phases. Advanced computer visualizations exist to alleviate these problems, but they are not equally effective for all students. One factor that might influence their effectiveness is students' existing levels of spatial ability. For example, external visualizations may act as prosthetics for students without well-developed visualization skills or they may favor students who already have highly developed spatial abilities. It is also unclear whether the use of such materials can in any way enhance a student's facility with the creation and manipulation of accurate mental models. We provide analysis of a study of spatial skills in Astronomy students and their relationship to learning about the Moon from a 3D GeoWall animation. We show which spatial skills prove relevant to phases and which students benefit the most from 3D-enhanced instruction.

  8. Shuttle Systems 3-D Applications: Application of 3-D Graphics in Engineering Training for Shuttle Ground Processing

    NASA Technical Reports Server (NTRS)

    Godfrey, Gary S.

    2003-01-01

    This project illustrates an animation of the orbiter mate to the external tank, an animation of the OMS POD installation to the orbiter, and a simulation of the landing gear mechanism at the Kennedy Space Center. A detailed storyboard was created to reflect each animation or simulation. Solid models were collected and translated into Pro/Engineer's prt and asm formats. These solid models included computer files of the: orbiter, external tank, solid rocket booster, mobile launch platform, transporter, vehicle assembly building, OMS POD fixture, and landing gear. A depository of the above solid models was established. These solid models were translated into several formats. This depository contained the following files: stl for sterolithography, stp for neutral file work, shrinkwrap for compression, tiff for photoshop work, jpeg for Internet use, and prt and asm for Pro/Engineer use. Solid models were created of the material handling sling, bay 3 platforms, and orbiter contact points. Animations were developed using mechanisms to reflect each storyboard. Every effort was made to build all models technically correct for engineering use. The result was an animated routine that could be used by NASA for training material handlers and uncovering engineering safety issues.

  9. Extensible 3D architecture for superconducting quantum computing

    NASA Astrophysics Data System (ADS)

    Liu, Qiang; Li, Mengmeng; Dai, Kunzhe; Zhang, Ke; Xue, Guangming; Tan, Xinsheng; Yu, Haifeng; Yu, Yang

    2017-06-01

    Using a multi-layered printed circuit board, we propose a 3D architecture suitable for packaging superconducting chips, especially chips that contain two-dimensional qubit arrays. In our proposed architecture, the center strips of the buried coplanar waveguides protrude from the surface of a dielectric layer as contacts. Since the contacts extend beyond the surface of the dielectric layer, chips can simply be flip-chip packaged with on-chip receptacles clinging to the contacts. Using this scheme, we packaged a multi-qubit chip and performed single-qubit and two-qubit quantum gate operations. The results indicate that this 3D architecture provides a promising scheme for scalable quantum computing.

  10. 3D seismic imaging on massively parallel computers

    SciTech Connect

    Womble, D.E.; Ober, C.C.; Oldfield, R.

    1997-02-01

    The ability to image complex geologies such as salt domes in the Gulf of Mexico and thrusts in mountainous regions is a key to reducing the risk and cost associated with oil and gas exploration. Imaging these structures, however, is computationally expensive. Datasets can be terabytes in size, and the processing time required for the multiple iterations needed to produce a velocity model can take months, even with the massively parallel computers available today. Some algorithms, such as 3D, finite-difference, prestack, depth migration remain beyond the capacity of production seismic processing. Massively parallel processors (MPPs) and algorithms research are the tools that will enable this project to provide new seismic processing capabilities to the oil and gas industry. The goals of this work are to (1) develop finite-difference algorithms for 3D, prestack, depth migration; (2) develop efficient computational approaches for seismic imaging and for processing terabyte datasets on massively parallel computers; and (3) develop a modular, portable, seismic imaging code.

  11. Fast precalculated triangular mesh algorithm for 3D binary computer-generated holograms.

    PubMed

    Yang, Fan; Kaczorowski, Andrzej; Wilkinson, Tim D

    2014-12-10

    A new method for constructing computer-generated holograms using a precalculated triangular mesh is presented. The speed of calculation can be increased dramatically by exploiting both the precalculated base triangle and GPU parallel computing. Unlike algorithms using point-based sources, this method can reconstruct a more vivid 3D object instead of a "hollow image." In addition, there is no need to do a fast Fourier transform for each 3D element every time. A ferroelectric liquid crystal spatial light modulator is used to display the binary hologram within our experiment and the hologram of a base right triangle is produced by utilizing just a one-step Fourier transform in the 2D case, which can be expanded to the 3D case by multiplying by a suitable Fresnel phase plane. All 3D holograms generated in this paper are based on Fresnel propagation; thus, the Fresnel plane is treated as a vital element in producing the hologram. A GeForce GTX 770 graphics card with 2 GB memory is used to achieve parallel computing.

  12. Graphics to H.264 video encoding for 3D scene representation and interaction on mobile devices using region of interest

    NASA Astrophysics Data System (ADS)

    Le, Minh Tuan; Nguyen, Congdu; Yoon, Dae-Il; Jung, Eun Ku; Jia, Jie; Kim, Hae-Kwang

    2007-12-01

    In this paper, we propose a method of 3D graphics to video encoding and streaming that are embedded into a remote interactive 3D visualization system for rapidly representing a 3D scene on mobile devices without having to download it from the server. In particular, a 3D graphics to video framework is presented that increases the visual quality of regions of interest (ROI) of the video by performing more bit allocation to ROI during H.264 video encoding. The ROI are identified by projection 3D objects to a 2D plane during rasterization. The system offers users to navigate the 3D scene and interact with objects of interests for querying their descriptions. We developed an adaptive media streaming server that can provide an adaptive video stream in term of object-based quality to the client according to the user's preferences and the variation of network bandwidth. Results show that by doing ROI mode selection, PSNR of test sample slightly change while visual quality of objects increases evidently.

  13. Computing Radiative Transfer in a 3D Medium

    NASA Technical Reports Server (NTRS)

    Von Allmen, Paul; Lee, Seungwon

    2012-01-01

    A package of software computes the time-dependent propagation of a narrow laser beam in an arbitrary three- dimensional (3D) medium with absorption and scattering, using the transient-discrete-ordinates method and a direct integration method. Unlike prior software that utilizes a Monte Carlo method, this software enables simulation at very small signal-to-noise ratios. The ability to simulate propagation of a narrow laser beam in a 3D medium is an improvement over other discrete-ordinate software. Unlike other direct-integration software, this software is not limited to simulation of propagation of thermal radiation with broad angular spread in three dimensions or of a laser pulse with narrow angular spread in two dimensions. Uses for this software include (1) computing scattering of a pulsed laser beam on a material having given elastic scattering and absorption profiles, and (2) evaluating concepts for laser-based instruments for sensing oceanic turbulence and related measurements of oceanic mixed-layer depths. With suitable augmentation, this software could be used to compute radiative transfer in ultrasound imaging in biological tissues, radiative transfer in the upper Earth crust for oil exploration, and propagation of laser pulses in telecommunication applications.

  14. AnimatLab: a 3D graphics environment for neuromechanical simulations.

    PubMed

    Cofer, David; Cymbalyuk, Gennady; Reid, James; Zhu, Ying; Heitler, William J; Edwards, Donald H

    2010-03-30

    The nervous systems of animals evolved to exert dynamic control of behavior in response to the needs of the animal and changing signals from the environment. To understand the mechanisms of dynamic control requires a means of predicting how individual neural and body elements will interact to produce the performance of the entire system. AnimatLab is a software tool that provides an approach to this problem through computer simulation. AnimatLab enables a computational model of an animal's body to be constructed from simple building blocks, situated in a virtual 3D world subject to the laws of physics, and controlled by the activity of a multicellular, multicompartment neural circuit. Sensor receptors on the body surface and inside the body respond to external and internal signals and then excite central neurons, while motor neurons activate Hill muscle models that span the joints and generate movement. AnimatLab provides a common neuromechanical simulation environment in which to construct and test models of any skeletal animal, vertebrate or invertebrate. The use of AnimatLab is demonstrated in a neuromechanical simulation of human arm flexion and the myotactic and contact-withdrawal reflexes. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  15. Interactive computer graphics: the arms race

    SciTech Connect

    Hafemeister, D.W.

    1983-01-01

    By using interactive computer graphics (ICG) it is possible to discuss the numerical aspects of some arms race issues with more specificity and in a visual way. The number of variables involved in these issues can be quite large; computers operated in the interactive, graphical mode, can allow exploration of the variables, leading to a greater understanding of the issues. This paper will examine some examples of interactive computer graphics: (1) the relationship between silo hardening and the accuracy, yield, and reliability of ICBMs; (2) target vulnerability (Minuteman, Dense Pack); (3) counterforce vs. countervalue weapons; (4) civil defense; (5) gravitational bias error; (6) MIRV; (7) national vulnerability to a preemptive first strike; (8) radioactive fallout; (9) digital-image processing with charge-coupled devices. 17 references, 11 figures, 1 table.

  16. Computer graphics aid mission operations. [NASA missions

    NASA Technical Reports Server (NTRS)

    Jeletic, James F.

    1990-01-01

    The application of computer graphics techniques in NASA space missions is reviewed. Telemetric monitoring of the Space Shuttle and its components is discussed, noting the use of computer graphics for real-time visualization problems in the retrieval and repair of the Solar Maximum Mission. The use of the world map display for determining a spacecraft's location above the earth and the problem of verifying the relative position and orientation of spacecraft to celestial bodies are examined. The Flight Dynamics/STS Three-dimensional Monitoring System and the Trajectroy Computations and Orbital Products System world map display are described, emphasizing Space Shuttle applications. Also, consideration is given to the development of monitoring systems such as the Shuttle Payloads Mission Monitoring System and the Attitude Heads-Up Display and the use of the NASA-Goddard Two-dimensional Graphics Monitoring System during Shuttle missions and to support the Hubble Space Telescope.

  17. Fast reduction of undersampling artifacts in radial MR angiography with 3D total variation on graphics hardware.

    PubMed

    Knoll, Florian; Unger, Markus; Diwoky, Clemens; Clason, Christian; Pock, Thomas; Stollberger, Rudolf

    2010-04-01

    Subsampling of radially encoded MRI acquisitions in combination with sparsity promoting methods opened a door to significantly increased imaging speed, which is crucial for many important clinical applications. In particular, it has been shown recently that total variation (TV) regularization efficiently reduces undersampling artifacts. The drawback of the method is the long reconstruction time which makes it impossible to use in daily clinical practice, especially if the TV optimization problem has to be solved repeatedly to select a proper regularization parameter. The goal of this work was to show that for the case of MR Angiography, TV filtering can be performed as a post-processing step, in contrast to the common approach of integrating TV penalties in the image reconstruction process. With this approach, it is possible to use TV algorithms with data fidelity terms in image space, which can be implemented very efficiently on graphic processing units (GPUs). The combination of a special radial sampling trajectory and a full 3D formulation of the TV minimization problem is crucial for the effectiveness of the artifact elimination process. The computation times of GPU-TV show that interactive elimination of undersampling artifacts is possible even for large volume data sets, in particular allowing the interactive determination of the regularization parameter. Results from phantom measurements and in vivo angiography data sets show that 3D TV, together with the proposed sampling trajectory, leads to pronounced improvements in image quality. However, while artifact removal was very efficient for angiography data sets in this work, it cannot be expected that the proposed method of TV post-processing will work for arbitrary types of scans.

  18. Fast high-resolution computer-generated hologram computation using multiple graphics processing unit cluster system.

    PubMed

    Takada, Naoki; Shimobaba, Tomoyoshi; Nakayama, Hirotaka; Shiraki, Atsushi; Okada, Naohisa; Oikawa, Minoru; Masuda, Nobuyuki; Ito, Tomoyoshi

    2012-10-20

    To overcome the computational complexity of a computer-generated hologram (CGH), we implement an optimized CGH computation in our multi-graphics processing unit cluster system. Our system can calculate a CGH of 6,400×3,072 pixels from a three-dimensional (3D) object composed of 2,048 points in 55 ms. Furthermore, in the case of a 3D object composed of 4096 points, our system is 553 times faster than a conventional central processing unit (using eight threads).

  19. Computer graphics production of switchgear engineering drawings

    SciTech Connect

    Jones, G.T.; Dodson, J.O.

    1982-11-01

    The opportunities for applying computer graphics and computer-aided design (CAD/CAM) to switchgear engineering drawings are examined in a case study of one switchgear manufacturer's computer system. This system is of unusual interest because it is particularly strong in two features which are seldom achieved: 1) flexibility in drawing layout and content, and 2) greater computer assistance in most steps in producing engineering drawings. An explanation of the choices, and capabilities in computer-aided design systems for switchgear is presented. In addition, guidelines in designing or choosing a system that allows flexibility and maximum computer assistance in producing the drawings are noted.

  20. 3D ultrasound computer tomography: update from a clinical study

    NASA Astrophysics Data System (ADS)

    Hopp, T.; Zapf, M.; Kretzek, E.; Henrich, J.; Tukalo, A.; Gemmeke, H.; Kaiser, C.; Knaudt, J.; Ruiter, N. V.

    2016-04-01

    Ultrasound Computer Tomography (USCT) is a promising new imaging method for breast cancer diagnosis. We developed a 3D USCT system and tested it in a pilot study with encouraging results: 3D USCT was able to depict two carcinomas, which were present in contrast enhanced MRI volumes serving as ground truth. To overcome severe differences in the breast shape, an image registration was applied. We analyzed the correlation between average sound speed in the breast and the breast density estimated from segmented MRIs and found a positive correlation with R=0.70. Based on the results of the pilot study we now carry out a successive clinical study with 200 patients. For this we integrated our reconstruction methods and image post-processing into a comprehensive workflow. It includes a dedicated DICOM viewer for interactive assessment of fused USCT images. A new preview mode now allows intuitive and faster patient positioning. We updated the USCT system to decrease the data acquisition time by approximately factor two and to increase the penetration depth of the breast into the USCT aperture by 1 cm. Furthermore the compute-intensive reflectivity reconstruction was considerably accelerated, now allowing a sub-millimeter volume reconstruction in approximately 16 minutes. The updates made it possible to successfully image first patients in our ongoing clinical study.

  1. Interactive computer graphics applications for compressible aerodynamics

    NASA Technical Reports Server (NTRS)

    Benson, Thomas J.

    1994-01-01

    Three computer applications have been developed to solve inviscid compressible fluids problems using interactive computer graphics. The first application is a compressible flow calculator which solves for isentropic flow, normal shocks, and oblique shocks or centered expansions produced by two dimensional ramps. The second application couples the solutions generated by the first application to a more graphical presentation of the results to produce a desk top simulator of three compressible flow problems: 1) flow past a single compression ramp; 2) flow past two ramps in series; and 3) flow past two opposed ramps. The third application extends the results of the second to produce a design tool which solves for the flow through supersonic external or mixed compression inlets. The applications were originally developed to run on SGI or IBM workstations running GL graphics. They are currently being extended to solve additional types of flow problems and modified to operate on any X-based workstation.

  2. General-Purpose Software For Computer Graphics

    NASA Technical Reports Server (NTRS)

    Rogers, Joseph E.

    1992-01-01

    NASA Device Independent Graphics Library (NASADIG) is general-purpose computer-graphics package for computer-based engineering and management applications which gives opportunity to translate data into effective graphical displays for presentation. Features include two- and three-dimensional plotting, spline and polynomial interpolation, control of blanking of areas, multiple log and/or linear axes, control of legends and text, control of thicknesses of curves, and multiple text fonts. Included are subroutines for definition of areas and axes of plots; setup and display of text; blanking of areas; setup of style, interpolation, and plotting of lines; control of patterns and of shading of colors; control of legends, blocks of text, and characters; initialization of devices; and setting of mixed alphabets. Written in FORTRAN 77.

  3. General-Purpose Software For Computer Graphics

    NASA Technical Reports Server (NTRS)

    Rogers, Joseph E.

    1992-01-01

    NASA Device Independent Graphics Library (NASADIG) is general-purpose computer-graphics package for computer-based engineering and management applications which gives opportunity to translate data into effective graphical displays for presentation. Features include two- and three-dimensional plotting, spline and polynomial interpolation, control of blanking of areas, multiple log and/or linear axes, control of legends and text, control of thicknesses of curves, and multiple text fonts. Included are subroutines for definition of areas and axes of plots; setup and display of text; blanking of areas; setup of style, interpolation, and plotting of lines; control of patterns and of shading of colors; control of legends, blocks of text, and characters; initialization of devices; and setting of mixed alphabets. Written in FORTRAN 77.

  4. Computational analysis of flow in 3D propulsive transition ducts

    NASA Technical Reports Server (NTRS)

    Sepri, Paavo

    1990-01-01

    A numerical analysis of fully three dimensional, statistically steady flows in propulsive transition ducts being considered for use in future aircraft of higher maneuverability is investigated. The purpose of the transition duct is to convert axisymmetric flow from conventional propulsion systems to that of a rectangular geometry of high aspect ratio. In an optimal design, the transition duct would be of minimal length in order to reduce the weight penalty, while the geometrical change would be gradual enough to avoid detrimental flow perturbations. Recent experiments conducted at the Propulsion Aerodynamics Branch have indicated that thrust losses in ducts of superelliptic cross-section can be surprisingly low, even if flow separation occurs near the divergent walls. In order to address the objective of developing a rational design procedure for optimal transition ducts, it is necessary to have available a reliable computational tool for the analysis of flows achieved in a sequence of configurations. Current CFD efforts involving complicated geometries usually must contend with two separate but interactive aspects: namely, grid generation and flow solution. The first two avenues of the present investigation were comprised of suitable grid generation for a class of transition ducts of superelliptic cross-section, and the subsequent application of the flow solver PAB3D to this geometry. The code, PAB3D, was developed as a comprehensive tool for the solution of both internal and external high speed flows. The third avenue of investigation has involved analytical formulations to aid in the understanding of the nature of duct flows, and also to provide a basis of comparison for subsequent numerical solutions. Numerical results to date include the generation of two preliminary grid systems for duct flows, and the initial application of PAB3D to the corresponding geometries, which are of the class tested experimentally.

  5. Computational model of mesenchymal migration in 3D under chemotaxis.

    PubMed

    Ribeiro, F O; Gómez-Benito, M J; Folgado, J; Fernandes, P R; García-Aznar, J M

    2017-01-01

    Cell chemotaxis is an important characteristic of cellular migration, which takes part in crucial aspects of life and development. In this work, we propose a novel in silico model of mesenchymal 3D migration with competing protrusions under a chemotactic gradient. Based on recent experimental observations, we identify three main stages that can regulate mesenchymal chemotaxis: chemosensing, dendritic protrusion dynamics and cell-matrix interactions. Therefore, each of these features is considered as a different module of the main regulatory computational algorithm. The numerical model was particularized for the case of fibroblast chemotaxis under a PDGF-bb gradient. Fibroblasts migration was simulated embedded in two different 3D matrices - collagen and fibrin - and under several PDGF-bb concentrations. Validation of the model results was provided through qualitative and quantitative comparison with in vitro studies. Our numerical predictions of cell trajectories and speeds were within the measured in vitro ranges in both collagen and fibrin matrices. Although in fibrin, the migration speed of fibroblasts is very low, because fibrin is a stiffer and more entangling matrix. Testing PDGF-bb concentrations, we noticed that an increment of this factor produces a speed increment. At 1 ng mL(-1) a speed peak is reached after which the migration speed diminishes again. Moreover, we observed that fibrin exerts a dampening behavior on migration, significantly affecting the migration efficiency.

  6. Computational model of mesenchymal migration in 3D under chemotaxis

    PubMed Central

    Ribeiro, F. O.; Gómez-Benito, M. J.; Folgado, J.; Fernandes, P. R.; García-Aznar, J. M.

    2017-01-01

    Abstract Cell chemotaxis is an important characteristic of cellular migration, which takes part in crucial aspects of life and development. In this work, we propose a novel in silico model of mesenchymal 3D migration with competing protrusions under a chemotactic gradient. Based on recent experimental observations, we identify three main stages that can regulate mesenchymal chemotaxis: chemosensing, dendritic protrusion dynamics and cell–matrix interactions. Therefore, each of these features is considered as a different module of the main regulatory computational algorithm. The numerical model was particularized for the case of fibroblast chemotaxis under a PDGF-bb gradient. Fibroblasts migration was simulated embedded in two different 3D matrices – collagen and fibrin – and under several PDGF-bb concentrations. Validation of the model results was provided through qualitative and quantitative comparison with in vitro studies. Our numerical predictions of cell trajectories and speeds were within the measured in vitro ranges in both collagen and fibrin matrices. Although in fibrin, the migration speed of fibroblasts is very low, because fibrin is a stiffer and more entangling matrix. Testing PDGF-bb concentrations, we noticed that an increment of this factor produces a speed increment. At 1 ng mL−1 a speed peak is reached after which the migration speed diminishes again. Moreover, we observed that fibrin exerts a dampening behavior on migration, significantly affecting the migration efficiency. PMID:27336322

  7. TOPICAL REVIEW: Computational approaches to 3D modeling of RNA

    NASA Astrophysics Data System (ADS)

    Laing, Christian; Schlick, Tamar

    2010-07-01

    Many exciting discoveries have recently revealed the versatility of RNA and its importance in a variety of functions within the cell. Since the structural features of RNA are of major importance to their biological function, there is much interest in predicting RNA structure, either in free form or in interaction with various ligands, including proteins, metabolites and other molecules. In recent years, an increasing number of researchers have developed novel RNA algorithms for predicting RNA secondary and tertiary structures. In this review, we describe current experimental and computational advances and discuss recent ideas that are transforming the traditional view of RNA folding. To evaluate the performance of the most recent RNA 3D folding algorithms, we provide a comparative study in order to test the performance of available 3D structure prediction algorithms for an RNA data set of 43 structures of various lengths and motifs. We find that the algorithms vary widely in terms of prediction quality across different RNA lengths and topologies; most predictions have very large root mean square deviations from the experimental structure. We conclude by outlining some suggestions for future RNA folding research.

  8. Applications of Computer Graphics in Engineering

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Various applications of interactive computer graphics to the following areas of science and engineering were described: design and analysis of structures, configuration geometry, animation, flutter analysis, design and manufacturing, aircraft design and integration, wind tunnel data analysis, architecture and construction, flight simulation, hydrodynamics, curve and surface fitting, gas turbine engine design, analysis, and manufacturing, packaging of printed circuit boards, spacecraft design.

  9. Computer Graphics Instruction in VizClass

    ERIC Educational Resources Information Center

    Grimes, Douglas; Warschauer, Mark; Hutchinson, Tara; Kuester, Falko

    2005-01-01

    "VizClass" is a university classroom environment designed to offer students in computer graphics and engineering courses up-to-date visualization technologies. Three digital whiteboards and a three-dimensional stereoscopic display provide complementary display surfaces. Input devices include touchscreens on the digital whiteboards, remote…

  10. Constructing Stylish Characters on Computer Graphics Systems.

    ERIC Educational Resources Information Center

    Goldman, Gary S.

    1980-01-01

    Computer graphics systems typically produce a single, machine-like character font. At most, these systems enable the user to (1) alter the aspect ratio (height-to-width ratio) of the characters, (2) specify a transformation matrix to slant the characters, and (3) define a virtual pen table to change the lineweight of the plotted characters.…

  11. Computer Graphics Instruction in VizClass

    ERIC Educational Resources Information Center

    Grimes, Douglas; Warschauer, Mark; Hutchinson, Tara; Kuester, Falko

    2005-01-01

    "VizClass" is a university classroom environment designed to offer students in computer graphics and engineering courses up-to-date visualization technologies. Three digital whiteboards and a three-dimensional stereoscopic display provide complementary display surfaces. Input devices include touchscreens on the digital whiteboards, remote…

  12. Two New Graphic Computer Dialogs for Teachers.

    ERIC Educational Resources Information Center

    Arons, Arnold; Bork, Alfred

    A pair of interactive computer-student dialogs developed for use primarily with elementary and high school teachers are described. The dialogs use graphic facilities for teaching about the sky as seen from the earth and about the phases of the moon. The primary aim is for the teachers to understand the nature of a scientific model, in this case…

  13. Computer Graphics Simulations of Sampling Distributions.

    ERIC Educational Resources Information Center

    Gordon, Florence S.; Gordon, Sheldon P.

    1989-01-01

    Describes the use of computer graphics simulations to enhance student understanding of sampling distributions that arise in introductory statistics. Highlights include the distribution of sample proportions, the distribution of the difference of sample means, the distribution of the difference of sample proportions, and the distribution of sample…

  14. Glasses for 3D ultrasound computer tomography: phase compensation

    NASA Astrophysics Data System (ADS)

    Zapf, M.; Hopp, T.; Ruiter, N. V.

    2016-03-01

    Ultrasound Computer Tomography (USCT), developed at KIT, is a promising new imaging system for breast cancer diagnosis, and was successfully tested in a pilot study. The 3D USCT II prototype consists of several hundreds of ultrasound (US) transducers on a semi-ellipsoidal aperture. Spherical waves are sequentially emitted by individual transducers and received in parallel by many transducers. Reflectivity volumes are reconstructed by synthetic aperture focusing (SAFT). However, straight forward SAFT imaging leads to blurred images due to system imperfections. We present an extension of a previously proposed approach to enhance the images. This approach includes additional a priori information and system characteristics. Now spatial phase compensation was included. The approach was evaluated with a simulation and clinical data sets. An increase in the image quality was observed and quantitatively measured by SNR and other metrics.

  15. 3D finite-difference seismic migration with parallel computers

    SciTech Connect

    Ober, C.C.; Gjertsen, R.; Minkoff, S.; Womble, D.E.

    1998-11-01

    The ability to image complex geologies such as salt domes in the Gulf of Mexico and thrusts in mountainous regions is essential for reducing the risk associated with oil exploration. Imaging these structures, however, is computationally expensive as datasets can be terabytes in size. Traditional ray-tracing migration methods cannot handle complex velocity variations commonly found near such salt structures. Instead the authors use the full 3D acoustic wave equation, discretized via a finite difference algorithm. They reduce the cost of solving the apraxial wave equation by a number of numerical techniques including the method of fractional steps and pipelining the tridiagonal solves. The imaging code, Salvo, uses both frequency parallelism (generally 90% efficient) and spatial parallelism (65% efficient). Salvo has been tested on synthetic and real data and produces clear images of the subsurface even beneath complicated salt structures.

  16. Parallelization of ARC3D with Computer-Aided Tools

    NASA Technical Reports Server (NTRS)

    Jin, Haoqiang; Hribar, Michelle; Yan, Jerry; Saini, Subhash (Technical Monitor)

    1998-01-01

    A series of efforts have been devoted to investigating methods of porting and parallelizing applications quickly and efficiently for new architectures, such as the SCSI Origin 2000 and Cray T3E. This report presents the parallelization of a CFD application, ARC3D, using the computer-aided tools, Cesspools. Steps of parallelizing this code and requirements of achieving better performance are discussed. The generated parallel version has achieved reasonably well performance, for example, having a speedup of 30 for 36 Cray T3E processors. However, this performance could not be obtained without modification of the original serial code. It is suggested that in many cases improving serial code and performing necessary code transformations are important parts for the automated parallelization process although user intervention in many of these parts are still necessary. Nevertheless, development and improvement of useful software tools, such as Cesspools, can help trim down many tedious parallelization details and improve the processing efficiency.

  17. Visualization and computer graphics on isotropically emissive volumetric displays.

    PubMed

    Mora, Benjamin; Maciejewski, Ross; Chen, Min; Ebert, David S

    2009-01-01

    The availability of commodity volumetric displays provides ordinary users with a new means of visualizing 3D data. Many of these displays are in the class of isotropically emissive light devices, which are designed to directly illuminate voxels in a 3D frame buffer, producing X-ray-like visualizations. While this technology can offer intuitive insight into a 3D object, the visualizations are perceptually different from what a computer graphics or visualization system would render on a 2D screen. This paper formalizes rendering on isotropically emissive displays and introduces a novel technique that emulates traditional rendering effects on isotropically emissive volumetric displays, delivering results that are much closer to what is traditionally rendered on regular 2D screens. Such a technique can significantly broaden the capability and usage of isotropically emissive volumetric displays. Our method takes a 3D dataset or object as the input, creates an intermediate light field, and outputs a special 3D volume dataset called a lumi-volume. This lumi-volume encodes approximated rendering effects in a form suitable for display with accumulative integrals along unobtrusive rays. When a lumi-volume is fed directly into an isotropically emissive volumetric display, it creates a 3D visualization with surface shading effects that are familiar to the users. The key to this technique is an algorithm for creating a 3D lumi-volume from a 4D light field. In this paper, we discuss a number of technical issues, including transparency effects due to the dimension reduction and sampling rates for light fields and lumi-volumes. We show the effectiveness and usability of this technique with a selection of experimental results captured from an isotropically emissive volumetric display, and we demonstrate its potential capability and scalability with computer-simulated high-resolution results.

  18. Computer graphics in architecture and engineering

    NASA Technical Reports Server (NTRS)

    Greenberg, D. P.

    1975-01-01

    The present status of the application of computer graphics to the building profession or architecture and its relationship to other scientific and technical areas were discussed. It was explained that, due to the fragmented nature of architecture and building activities (in contrast to the aerospace industry), a comprehensive, economic utilization of computer graphics in this area is not practical and its true potential cannot now be realized due to the present inability of architects and structural, mechanical, and site engineers to rely on a common data base. Future emphasis will therefore have to be placed on a vertical integration of the construction process and effective use of a three-dimensional data base, rather than on waiting for any technological breakthrough in interactive computing.

  19. Computational and methodological developments towards 3D full waveform inversion

    NASA Astrophysics Data System (ADS)

    Etienne, V.; Virieux, J.; Hu, G.; Jia, Y.; Operto, S.

    2010-12-01

    Full waveform inversion (FWI) is one of the most promising techniques for seismic imaging. It relies on a formalism taking into account every piece of information contained in the seismic data as opposed to more classical techniques such as travel time tomography. As a result, FWI is a high resolution imaging process able to reach a spatial accuracy equal to half a wavelength. FWI is based on a local optimization scheme and therefore the main limitation concerns the starting model which has to be closed enough to the real one in order to converge to the global minimum. Another counterpart of FWI is the required computational resources when considering models and frequencies of interest. The task becomes even more tremendous when one tends to perform the inversion using the elastic equation instead of using the acoustic approximation. This is the reason why until recently most studies were limited to 2D cases. In the last few years, due to the increase of the available computational power, FWI has focused a lot of interests and continuous efforts towards inversion of 3D models, leading to remarkable applications up to the continental scale. We investigate the computational burden induced by FWI in 3D elastic media and propose some strategic features leading to the reduction of the numerical cost while providing a great flexibility in the inversion parametrization. First, in order to release the memory requirements, we developed our FWI algorithm in the frequency domain and take benefit of the wave-number redundancy in the seismic data to process a quite reduced number of frequencies. To do so, we extract frequency solutions from time marching techniques which are efficient for 3D structures. Moreover, this frequency approach permits a multi-resolution strategy by proceeding from low to high frequencies: the final model at one frequency is used as the starting model for the next frequency. This procedure overcomes partially the non-linear behavior of the inversion

  20. Protein 3D Structure Computed from Evolutionary Sequence Variation

    PubMed Central

    Sheridan, Robert; Hopf, Thomas A.; Pagnani, Andrea; Zecchina, Riccardo; Sander, Chris

    2011-01-01

    The evolutionary trajectory of a protein through sequence space is constrained by its function. Collections of sequence homologs record the outcomes of millions of evolutionary experiments in which the protein evolves according to these constraints. Deciphering the evolutionary record held in these sequences and exploiting it for predictive and engineering purposes presents a formidable challenge. The potential benefit of solving this challenge is amplified by the advent of inexpensive high-throughput genomic sequencing. In this paper we ask whether we can infer evolutionary constraints from a set of sequence homologs of a protein. The challenge is to distinguish true co-evolution couplings from the noisy set of observed correlations. We address this challenge using a maximum entropy model of the protein sequence, constrained by the statistics of the multiple sequence alignment, to infer residue pair couplings. Surprisingly, we find that the strength of these inferred couplings is an excellent predictor of residue-residue proximity in folded structures. Indeed, the top-scoring residue couplings are sufficiently accurate and well-distributed to define the 3D protein fold with remarkable accuracy. We quantify this observation by computing, from sequence alone, all-atom 3D structures of fifteen test proteins from different fold classes, ranging in size from 50 to 260 residues., including a G-protein coupled receptor. These blinded inferences are de novo, i.e., they do not use homology modeling or sequence-similar fragments from known structures. The co-evolution signals provide sufficient information to determine accurate 3D protein structure to 2.7–4.8 Å Cα-RMSD error relative to the observed structure, over at least two-thirds of the protein (method called EVfold, details at http://EVfold.org). This discovery provides insight into essential interactions constraining protein evolution and will facilitate a comprehensive survey of the universe of protein

  1. Protein 3D structure computed from evolutionary sequence variation.

    PubMed

    Marks, Debora S; Colwell, Lucy J; Sheridan, Robert; Hopf, Thomas A; Pagnani, Andrea; Zecchina, Riccardo; Sander, Chris

    2011-01-01

    The evolutionary trajectory of a protein through sequence space is constrained by its function. Collections of sequence homologs record the outcomes of millions of evolutionary experiments in which the protein evolves according to these constraints. Deciphering the evolutionary record held in these sequences and exploiting it for predictive and engineering purposes presents a formidable challenge. The potential benefit of solving this challenge is amplified by the advent of inexpensive high-throughput genomic sequencing.In this paper we ask whether we can infer evolutionary constraints from a set of sequence homologs of a protein. The challenge is to distinguish true co-evolution couplings from the noisy set of observed correlations. We address this challenge using a maximum entropy model of the protein sequence, constrained by the statistics of the multiple sequence alignment, to infer residue pair couplings. Surprisingly, we find that the strength of these inferred couplings is an excellent predictor of residue-residue proximity in folded structures. Indeed, the top-scoring residue couplings are sufficiently accurate and well-distributed to define the 3D protein fold with remarkable accuracy.We quantify this observation by computing, from sequence alone, all-atom 3D structures of fifteen test proteins from different fold classes, ranging in size from 50 to 260 residues, including a G-protein coupled receptor. These blinded inferences are de novo, i.e., they do not use homology modeling or sequence-similar fragments from known structures. The co-evolution signals provide sufficient information to determine accurate 3D protein structure to 2.7-4.8 Å C(α)-RMSD error relative to the observed structure, over at least two-thirds of the protein (method called EVfold, details at http://EVfold.org). This discovery provides insight into essential interactions constraining protein evolution and will facilitate a comprehensive survey of the universe of protein structures

  2. Applications of 3D orbital computer-assisted surgery (CAS).

    PubMed

    Scolozzi, P

    2017-09-01

    The purpose of the present report is to describe the indications for use of 3D orbital computer-assisted surgery (CAS). We analyzed the clinical and radiological data of all patients with orbital deformities treated using intra-operative navigation and CAD/CAM techniques at the Hôpitaux Universitaires de Genève, Switzerland, between 2009 and 2016. We recorded age and gender, orbital deformity, technical and surgical procedure and postoperative complications. One hundred and three patients were included. Mean age was 39.5years (range, 5 to 84years) and 85 (87.5%) were men. Of the 103 patients, 96 had intra-operative navigation (34 for primary and 3 for secondary orbito-zygomatic fractures, 15 for Le Fort fractures, 16 for orbital floor fractures, 10 for combined orbital floor and medial wall fractures, 7 for orbital medial wall fractures, 3 for NOE (naso-orbito-ethmoidal) fractures, 2 for isolated comminuted zygomatic arch fractures, 1 for enophthalmos, 3 for TMJ ankylosis and 2 for fibrous dysplasia bone recontouring), 8 patients had CAD/CAM PEEK-PSI for correction of residual orbital bone contour following craniomaxillofacial trauma, and 1 patient had CAD/CAM surgical splints and cutting guides for correction of orbital hypertelorism. Two patient (1.9%) required revision surgery for readjustment of an orbital mesh. The 1-year follow-up examination showed stable cosmetic and dimensional results in all patients. This study demonstrated that the application of 3D orbital CAS with regards to intra-operative navigation and CAD/CAM techniques allowed for a successful outcome in the patients presented in this series. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  3. 3D Computer aided treatment planning in endodontics.

    PubMed

    van der Meer, Wicher J; Vissink, Arjan; Ng, Yuan Ling; Gulabivala, Kishor

    2016-02-01

    Obliteration of the root canal system due to accelerated dentinogenesis and dystrophic calcification can challenge the achievement of root canal treatment goals. This paper describes the application of 3D digital mapping technology for predictable navigation of obliterated canal systems during root canal treatment to avoid iatrogenic damage of the root. Digital endodontic treatment planning for anterior teeth with severely obliterated root canal systems was accomplished with the aid of computer software, based on cone beam computer tomography (CBCT) scans and intra-oral scans of the dentition. On the basis of these scans, endodontic guides were created for the planned treatment through digital designing and rapid prototyping fabrication. The custom-made guides allowed for an uncomplicated and predictable canal location and management. The method of digital designing and rapid prototyping of endodontic guides allows for reliable and predictable location of root canals of teeth with calcifically metamorphosed root canal systems. The endodontic directional guide facilitates difficult endodontic treatments at little additional cost. Copyright © 2016. Published by Elsevier Ltd.

  4. Identification of Learning Processes by Means of Computer Graphics.

    ERIC Educational Resources Information Center

    Sorensen, Birgitte Holm

    1993-01-01

    Describes a development project for the use of computer graphics and video in connection with an inservice training course for primary education teachers in Denmark. Topics addressed include research approaches to computers; computer graphics in learning processes; activities relating to computer graphics; the role of the teacher; and student…

  5. 3D Vectorial Time Domain Computational Integrated Photonics

    SciTech Connect

    Kallman, J S; Bond, T C; Koning, J M; Stowell, M L

    2007-02-16

    The design of integrated photonic structures poses considerable challenges. 3D-Time-Domain design tools are fundamental in enabling technologies such as all-optical logic, photonic bandgap sensors, THz imaging, and fast radiation diagnostics. Such technologies are essential to LLNL and WFO sponsors for a broad range of applications: encryption for communications and surveillance sensors (NSA, NAI and IDIV/PAT); high density optical interconnects for high-performance computing (ASCI); high-bandwidth instrumentation for NIF diagnostics; micro-sensor development for weapon miniaturization within the Stockpile Stewardship and DNT programs; and applications within HSO for CBNP detection devices. While there exist a number of photonics simulation tools on the market, they primarily model devices of interest to the communications industry. We saw the need to extend our previous software to match the Laboratory's unique emerging needs. These include modeling novel material effects (such as those of radiation induced carrier concentrations on refractive index) and device configurations (RadTracker bulk optics with radiation induced details, Optical Logic edge emitting lasers with lateral optical inputs). In addition we foresaw significant advantages to expanding our own internal simulation codes: parallel supercomputing could be incorporated from the start, and the simulation source code would be accessible for modification and extension. This work addressed Engineering's Simulation Technology Focus Area, specifically photonics. Problems addressed from the Engineering roadmap of the time included modeling the Auston switch (an important THz source/receiver), modeling Vertical Cavity Surface Emitting Lasers (VCSELs, which had been envisioned as part of fast radiation sensors), and multi-scale modeling of optical systems (for a variety of applications). We proposed to develop novel techniques to numerically solve the 3D multi-scale propagation problem for both the microchip

  6. Three-dimensional range data compression using computer graphics rendering pipeline.

    PubMed

    Zhang, Song

    2012-06-20

    This paper presents the idea of naturally encoding three-dimensional (3D) range data into regular two-dimensional (2D) images utilizing computer graphics rendering pipeline. The computer graphics pipeline provides a means to sample 3D geometry data into regular 2D images, and also to retrieve the depth information for each sampled pixel. The depth information for each pixel is further encoded into red, green, and blue color channels of regular 2D images. The 2D images can further be compressed with existing 2D image compression techniques. By this novel means, 3D geometry data obtained by 3D range scanners can be instantaneously compressed into 2D images, providing a novel way of storing 3D range data into its 2D counterparts. We will present experimental results to verify the performance of this proposed technique.

  7. Computer acquisition of 3D images utilizing dynamic speckles

    NASA Astrophysics Data System (ADS)

    Kamshilin, Alexei A.; Semenov, Dmitry V.; Nippolainen, Ervin; Raita, Erik

    2006-05-01

    We present novel technique for fast non-contact and continuous profile measurements of rough surfaces by use of dynamic speckles. The dynamic speckle pattern is generated when the laser beam scans the surface under study. The most impressive feature of the proposed technique is its ability to work at extremely high scanning speed of hundreds meters per second. The technique is based on the continuous frequency measurements of the light-power modulation after spatial filtering of the scattered light. The complete optical-electronic system was designed and fabricated for fast measurement of the speckles velocity, its recalculation into the distance, and further data acquisition into computer. The measured surface profile is displayed in a PC monitor in real time. The response time of the measuring system is below 1 μs. Important parameters of the system such as accuracy, range of measurements, and spatial resolution are analyzed. Limits of the spatial filtering technique used for continuous tracking of the speckle-pattern velocity are shown. Possible ways of further improvement of the measurements accuracy are demonstrated. Owing to its extremely fast operation, the proposed technique could be applied for online control of the 3D-shape of complex objects (e.g., electronic circuits) during their assembling.

  8. Computation of 3D queries for ROCS based virtual screens.

    PubMed

    Tawa, Gregory J; Baber, J Christian; Humblet, Christine

    2009-12-01

    Rapid overlay of chemical structures (ROCS) is a method that aligns molecules based on shape and/or chemical similarity. It is often used in 3D ligand-based virtual screening. Given a query consisting of a single conformation of an active molecule ROCS can generate highly enriched hit lists. Typically the chosen query conformation is a minimum energy structure. Can better enrichment be obtained using conformations other than the minimum energy structure? To answer this question a methodology has been developed called CORAL (COnformational analysis, Rocs ALignment). For a given set of molecule conformations it computes optimized conformations for ROCS screening. It does so by clustering all conformations of a chosen molecule set using pairwise ROCS combo scores. The best representative conformation is that which has the highest average overlap with the rest of the conformations in the cluster. It is these best representative conformations that are then used for virtual screening. CORAL was tested by performing virtual screening experiments with the 40 DUD (Directory of Useful Decoys) data sets. Both CORAL and minimum energy queries were used. The recognition capability of each query was quantified as the area under the ROC curve (AUC). Results show that the CORAL AUC values are on average larger than the minimum energy AUC values. This demonstrates that one can indeed obtain better ROCS enrichments with conformations other than the minimum energy structure. As a result, CORAL analysis can be a valuable first step in virtual screening workflows using ROCS.

  9. Computation of 3D queries for ROCS based virtual screens

    NASA Astrophysics Data System (ADS)

    Tawa, Gregory J.; Baber, J. Christian; Humblet, Christine

    2009-12-01

    Rapid overlay of chemical structures (ROCS) is a method that aligns molecules based on shape and/or chemical similarity. It is often used in 3D ligand-based virtual screening. Given a query consisting of a single conformation of an active molecule ROCS can generate highly enriched hit lists. Typically the chosen query conformation is a minimum energy structure. Can better enrichment be obtained using conformations other than the minimum energy structure? To answer this question a methodology has been developed called CORAL (COnformational analysis, Rocs ALignment). For a given set of molecule conformations it computes optimized conformations for ROCS screening. It does so by clustering all conformations of a chosen molecule set using pairwise ROCS combo scores. The best representative conformation is that which has the highest average overlap with the rest of the conformations in the cluster. It is these best representative conformations that are then used for virtual screening. CORAL was tested by performing virtual screening experiments with the 40 DUD (Directory of Useful Decoys) data sets. Both CORAL and minimum energy queries were used. The recognition capability of each query was quantified as the area under the ROC curve (AUC). Results show that the CORAL AUC values are on average larger than the minimum energy AUC values. This demonstrates that one can indeed obtain better ROCS enrichments with conformations other than the minimum energy structure. As a result, CORAL analysis can be a valuable first step in virtual screening workflows using ROCS.

  10. Real-time computer-generated integral imaging and 3D image calibration for augmented reality surgical navigation.

    PubMed

    Wang, Junchen; Suenaga, Hideyuki; Liao, Hongen; Hoshi, Kazuto; Yang, Liangjing; Kobayashi, Etsuko; Sakuma, Ichiro

    2015-03-01

    Autostereoscopic 3D image overlay for augmented reality (AR) based surgical navigation has been studied and reported many times. For the purpose of surgical overlay, the 3D image is expected to have the same geometric shape as the original organ, and can be transformed to a specified location for image overlay. However, how to generate a 3D image with high geometric fidelity and quantitative evaluation of 3D image's geometric accuracy have not been addressed. This paper proposes a graphics processing unit (GPU) based computer-generated integral imaging pipeline for real-time autostereoscopic 3D display, and an automatic closed-loop 3D image calibration paradigm for displaying undistorted 3D images. Based on the proposed methods, a novel AR device for 3D image surgical overlay is presented, which mainly consists of a 3D display, an AR window, a stereo camera for 3D measurement, and a workstation for information processing. The evaluation on the 3D image rendering performance with 2560×1600 elemental image resolution shows the rendering speeds of 50-60 frames per second (fps) for surface models, and 5-8 fps for large medical volumes. The evaluation of the undistorted 3D image after the calibration yields sub-millimeter geometric accuracy. A phantom experiment simulating oral and maxillofacial surgery was also performed to evaluate the proposed AR overlay device in terms of the image registration accuracy, 3D image overlay accuracy, and the visual effects of the overlay. The experimental results show satisfactory image registration and image overlay accuracy, and confirm the system usability.

  11. RGUI 1.0, New Graphical User Interface for RELAP5-3D

    SciTech Connect

    Mesina, George Lee; Galbraith, James Andrew

    1999-04-01

    With the advent of three-dimensional modeling in nuclear safety analysis codes, the need has arisen for a new display methodology. Currently, analysts either sort through voluminous numerical displays of data at points in a region, or view color coded interpretations of the data on a two-dimensional rendition of the plant. RGUI 1.0 provides 3D capability for displaying data. The 3D isometric hydrodynamic image is built automatically from the input deck without additional input from the user. Standard view change features allow the user to focus on only the important data. Familiar features that are standard to the nuclear industry, such as run, interact, and monitor, are included. RGUI 1.0 reduces the difficulty of analyzing complex three dimensional plants.

  12. RGUI 1.0, New Graphical User Interface for RELAP5-3D

    SciTech Connect

    G. L. Mesina; J. Galbraith

    1999-04-01

    With the advent of three-dimensional modeling in nuclear safety analysis codes, the need has arisen for a new display methodology. Currently, analysts either sort through voluminous numerical displays of data at points in a region, or view color coded interpretations of the data on a two-dimensional rendition of the plant. RGUI 1.0 provides 3D capability for displaying data. The 3D isometric hydrodynamic image is built automatically from the input deck without additional input from the user. Standard view change features allow the user to focus on only the important data. Familiar features that are standard to the nuclear industry, such as run, interact, and monitor, are included. RGUI 1.0 reduces the difficulty of analyzing complex three-dimensional plants.

  13. Real Time Computer Graphics From Body Motion

    NASA Astrophysics Data System (ADS)

    Fisher, Scott; Marion, Ann

    1983-10-01

    This paper focuses on the recent emergence and development of real, time, computer-aided body tracking technologies and their use in combination with various computer graphics imaging techniques. The convergence of these, technologies in our research results, in an interactive display environment. in which multipde, representations of a given body motion can be displayed in real time. Specific reference, to entertainment applications is described in the development of a real time, interactive stage set in which dancers can 'draw' with their bodies as they move, through the space. of the stage or manipulate virtual elements of the set with their gestures.

  14. Global trajectory targeting via computer graphics

    NASA Technical Reports Server (NTRS)

    Mann, F. I.

    1971-01-01

    A technique is described in which the two-point boundary value problem (TPBVP) may be solved with the aid of interactive computer graphics. The particular TPBVP considered is the optimal electric propulsion space trajectory problem. An appropriate two-dimensional projection of the TPBVP mapping, or trajectory, is displayed on the computer's television screen, and a man-in-the-loop varies selected trajectory starting conditions in the fashion of a nonlinear walk until the viewed trajectory endpoint lies near a displayed target. Once global targeting is accomplished in this manner, program internal logic can easily handle local targeting to strongly solve the TPBVP.

  15. Real World Issues in Developing a Malaysian Forest Battlefield Environment for Small Unit Tactics Using 3D Graphics

    NASA Astrophysics Data System (ADS)

    Alsagoff, Syed Nasir

    In the military, training is essential as preparation for war. Small unit training involves training for platoon and section sized unit. The soldiers must train to maneuver, shoot and communicate. In order for the training to be successful, it must be as realistic as possible. Realistic training allows for the soldiers to be mentally and physically prepared for the battlefield. Unfortunately, there is a wide gap between training and the resources required to properly conduct the training [5]. Resources consist of suitable training location and material support such as ammunition, ration and fuel. Limitation on the resources means that training cannot be as realistic as possible. To ensure effective use of the limited training resources, training should be conducted in a simulated environment before migrating to a live environment. This paper will attempt to discuss the real world issues in developing a Malaysian Forest Battlefield Environment 3D Simulation for Small Unit Tactic using 3D Graphics.

  16. Computer graphics applications to crew displays

    NASA Technical Reports Server (NTRS)

    Wyzkoski, J.

    1983-01-01

    Astronauts are provided much data and information via the monochrome CRT displays on the orbiter. For this project two areas were investigated for the possible introduction of computer graphics to enhance and extend the utility of these displays. One involved reviewing the current orbiter displays and identifying those which could be improved via computer graphics. As an example, the tabular data on electrical power distribution and control was enhanced by the addition of color and bar charts. The other dealt with the development of an aid to berthing a payload with the Remote Manipulator System (RMS). This aid consists of a graphics display of the top, front and side views of the payload and cargo bay and point of resolution (POR) position and attitude data for the current location of the payload. The initial implementation was on an IBM PC clone. The demonstration software installed in the Johnson Space Center Manipulator Development Facility (MD) was reviewed. Due to current hardware limitations, the MDF verision is slow, i.e., about a 40+ seond update rate and, hence, not real-time. Despite this fact, the evaluation of this additional visual cue as an RMS operator aid indicates that this display, with modifications for speed, etc., can assist the crew. Further development is appropriate.

  17. Cross-Platform Graphical User Interface with fast 3-D Rendering for Particle-in-Cell Simulations

    NASA Astrophysics Data System (ADS)

    Bruhwiler, David; Luetkemeyer, Kelly; Cary, John

    1999-11-01

    The Graphical User Interface (GUI) for XOOPIC (X11-based Object-Oriented Particle-in-Cell) is being ported to Qt, a cross-platform C++ windowing toolkit, thus permitting the code to run on PC's running both Windows 95/98/NT and Linux, as well as all commercial Unix platforms. All 3-D graphics will be handled through OpenGL, the cross-platform standard for fast 3-D rendering. The use of object-oriented design (OOD) techniques keeps the GUI/physics interface clean, and minimizes the impact of GUI development on the physics code. OOD also improves the maintainability and extensibility of large scientific simulation codes, while allowing for cross-platform portability and ready interchange of individual algorithms or entire physics kernels. Planned new GUI features include interactive modifications of the simulation parameters, including generation of a slowly-varying mesh and automatic updating of a corresponding input file. Improved modeling of high-power microwave tubes is one of the primary applications being targeted by this project.

  18. 2005 DOE Computer Graphics Forum Site Survey

    SciTech Connect

    Rebecca, S; Eric, B

    2005-04-15

    The Information Management and Graphics Group supports and develops tools that enhance our ability to access, display, and understand large, complex data sets. Activities include developing visualization software for terascale data exploration; running two video production labs; supporting graphics libraries and tools for end users; maintaining four PowerWalls and assorted other advanced displays; and providing integrated tools for searching, organizing, and browsing scientific data. The Data group supports Defense and Nuclear technologies (D&NT) Directorate. The group's visualization team has developed and maintains two visualization tools: MeshTV and VisIt. These are interactive graphical analysis tools for visualizing and analyzing data on two- and three-dimensional meshes. They also provide movie production support. Researchers in the Center for Applied Scientific Computing (CASC) work on various projects including the development of visualization and data mining techniques for terascale data exploration that are funded by ASC. The researchers also have LDRD projects and collaborations with other lab researchers, academia, and industry.

  19. 3D fast adaptive correlation imaging for large-scale gravity data based on GPU computation

    NASA Astrophysics Data System (ADS)

    Chen, Z.; Meng, X.; Guo, L.; Liu, G.

    2011-12-01

    comtinue to perform 3D correlation imaging for the redisual gravity data. After several iterations, we can obtain a satisfactoy results. Newly developed general purpose computing technology from Nvidia GPU (Graphics Processing Unit) has been put into practice and received widespread attention in many areas. Based on the GPU programming mode and two parallel levels, five CPU loops for the main computation of 3D correlation imaging are converted into three loops in GPU kernel functions, thus achieving GPU/CPU collaborative computing. The two inner loops are defined as the dimensions of blocks and the three outer loops are defined as the dimensions of threads, thus realizing the double loop block calculation. Theoretical and real gravity data tests show that results are reliable and the computing time is greatly reduced. Acknowledgments We acknowledge the financial support of Sinoprobe project (201011039 and 201011049-03), the Fundamental Research Funds for the Central Universities (2010ZY26 and 2011PY0183), the National Natural Science Foundation of China (41074095) and the Open Project of State Key Laboratory of Geological Processes and Mineral Resources (GPMR0945).

  20. Learning Projectile Motion with the Computer Game "Scorched 3D"

    ERIC Educational Resources Information Center

    Jurcevic, John S.

    2008-01-01

    For most of our students, video games are a normal part of their lives. We should take advantage of this medium to teach physics in a manner that is engrossing for our students. In particular, modern video games incorporate accurate physics in their game engines, and they allow us to visualize the physics through flashy and captivating graphics. I…

  1. Learning Projectile Motion with the Computer Game "Scorched 3D"

    ERIC Educational Resources Information Center

    Jurcevic, John S.

    2008-01-01

    For most of our students, video games are a normal part of their lives. We should take advantage of this medium to teach physics in a manner that is engrossing for our students. In particular, modern video games incorporate accurate physics in their game engines, and they allow us to visualize the physics through flashy and captivating graphics. I…

  2. Graphics Programs for the DEC VAX Computer

    NASA Technical Reports Server (NTRS)

    Long, D.

    1986-01-01

    Variety of plots available in video or printed form. LONGLIB library of computer programs set of subroutines designed for vector plotting on cathode-ray tubes and dot-matrix printers. LONGLIB subroutines invoked by program calls similar to standard CALCOMP routines. In addition to basic plotting routines, LONGLIB contains extensive set of routines to allow viewport clipping, extended character sets, graphic input, gray-level plots, polar plots, and three-dimensional plotting with or without removal of hidden lines. LONGLIB written in FORTRAN 77 and C for batch execution.

  3. When Do Computer Graphics Contribute to Early Literacy Learning?

    ERIC Educational Resources Information Center

    Wepner, Shelley B.; Cotter, Michelle

    2002-01-01

    Notes that new literacies use computer graphics to tell a story, demonstrate a theory, or support a definition. Offers a functionality framework for assessing the value of computer graphics for early literacy learning. Provides ideas for determining the value of CD-ROM software and websites. Concludes that graphics that give text meaning or…

  4. Real-time 3D and 4D Fourier domain Doppler optical coherence tomography based on dual graphics processing units.

    PubMed

    Huang, Yong; Liu, Xuan; Kang, Jin U

    2012-09-01

    We present real-time 3D (2D cross-sectional image plus time) and 4D (3D volume plus time) phase-resolved Doppler OCT (PRDOCT) imaging based on configuration of dual graphics processing units (GPU). A GPU-accelerated phase-resolving processing algorithm was developed and implemented. We combined a structural image intensity-based thresholding mask and average window method to improve the signal-to-noise ratio of the Doppler phase image. A 2D simultaneous display of the structure and Doppler flow images was presented at a frame rate of 70 fps with an image size of 1000 × 1024 (X × Z) pixels. A 3D volume rendering of tissue structure and flow images-each with a size of 512 × 512 pixels-was presented 64.9 milliseconds after every volume scanning cycle with a volume size of 500 × 256 × 512 (X × Y × Z) voxels, with an acquisition time window of only 3.7 seconds. To the best of our knowledge, this is the first time that an online, simultaneous structure and Doppler flow volume visualization has been achieved. Maximum system processing speed was measured to be 249,000 A-scans per second with each A-scan size of 2048 pixels.

  5. Real-time 3D and 4D Fourier domain Doppler optical coherence tomography based on dual graphics processing units

    PubMed Central

    Huang, Yong; Liu, Xuan; Kang, Jin U.

    2012-01-01

    We present real-time 3D (2D cross-sectional image plus time) and 4D (3D volume plus time) phase-resolved Doppler OCT (PRDOCT) imaging based on configuration of dual graphics processing units (GPU). A GPU-accelerated phase-resolving processing algorithm was developed and implemented. We combined a structural image intensity-based thresholding mask and average window method to improve the signal-to-noise ratio of the Doppler phase image. A 2D simultaneous display of the structure and Doppler flow images was presented at a frame rate of 70 fps with an image size of 1000 × 1024 (X × Z) pixels. A 3D volume rendering of tissue structure and flow images—each with a size of 512 × 512 pixels—was presented 64.9 milliseconds after every volume scanning cycle with a volume size of 500 × 256 × 512 (X × Y × Z) voxels, with an acquisition time window of only 3.7 seconds. To the best of our knowledge, this is the first time that an online, simultaneous structure and Doppler flow volume visualization has been achieved. Maximum system processing speed was measured to be 249,000 A-scans per second with each A-scan size of 2048 pixels. PMID:23024910

  6. Modeling Computer Communication Networks in a Realistic 3D Environment

    DTIC Science & Technology

    2010-03-01

    visualization in OPNET . . . . . . . . . . . . 13 6. Sample NetViz visualization . . . . . . . . . . . . . . . . . . . 15 7. Realistic 3D terrains...scenario in OPNET . . . 19 10. OPNET 3DNV only displays connectivity . . . . . . . . . . . . 29 11. The digitally connected battlefield...confirmation tool 12 OPNET Optimized Network Evaluation Tool . . . . . . . . . . . . 13 NetViz Network Visualization

  7. Machine learning-based 3-D geometry reconstruction and modeling of aortic valve deformation using 3-D computed tomography images.

    PubMed

    Liang, Liang; Kong, Fanwei; Martin, Caitlin; Pham, Thuy; Wang, Qian; Duncan, James; Sun, Wei

    2017-05-01

    To conduct a patient-specific computational modeling of the aortic valve, 3-D aortic valve anatomic geometries of an individual patient need to be reconstructed from clinical 3-D cardiac images. Currently, most of computational studies involve manual heart valve geometry reconstruction and manual finite element (FE) model generation, which is both time-consuming and prone to human errors. A seamless computational modeling framework, which can automate this process based on machine learning algorithms, is desirable, as it can not only eliminate human errors and ensure the consistency of the modeling results but also allow fast feedback to clinicians and permits a future population-based probabilistic analysis of large patient cohorts. In this study, we developed a novel computational modeling method to automatically reconstruct the 3-D geometries of the aortic valve from computed tomographic images. The reconstructed valve geometries have built-in mesh correspondence, which bridges harmonically for the consequent FE modeling. The proposed method was evaluated by comparing the reconstructed geometries from 10 patients with those manually created by human experts, and a mean discrepancy of 0.69 mm was obtained. Based on these reconstructed geometries, FE models of valve leaflets were developed, and aortic valve closure from end systole to middiastole was simulated for 7 patients and validated by comparing the deformed geometries with those manually created by human experts, and a mean discrepancy of 1.57 mm was obtained. The proposed method offers great potential to streamline the computational modeling process and enables the development of a preoperative planning system for aortic valve disease diagnosis and treatment. Copyright © 2016 John Wiley & Sons, Ltd.

  8. Computed 3D visualisation of an extinct cephalopod using computer tomographs

    PubMed Central

    Lukeneder, Alexander

    2012-01-01

    The first 3D visualisation of a heteromorph cephalopod species from the Southern Alps (Dolomites, northern Italy) is presented. Computed tomography, palaeontological data and 3D reconstructions were included in the production of a movie, which shows a life reconstruction of the extinct organism. This detailed reconstruction is according to the current knowledge of the shape and mode of life as well as habitat of this animal. The results are based on the most complete shell known thus far of the genus Dissimilites. Object-based combined analyses from computed tomography and various computed 3D facility programmes help to understand morphological details as well as their ontogentical changes in fossil material. In this study, an additional goal was to show changes in locomotion during different ontogenetic phases of such fossil, marine shell-bearing animals (ammonoids). Hence, the presented models and tools can serve as starting points for discussions on morphology and locomotion of extinct cephalopods in general, and of the genus Dissimilites in particular. The heteromorph ammonoid genus Dissimilites is interpreted here as an active swimmer of the Tethyan Ocean. This study portrays non-destructive methods of 3D visualisation applied on palaeontological material, starting with computed tomography resulting in animated, high-quality video clips. The here presented 3D geometrical models and animation, which are based on palaeontological material, demonstrate the wide range of applications, analytical techniques and also outline possible limitations of 3D models in earth sciences and palaeontology. The realistic 3D models and motion pictures can easily be shared amongst palaeontologists. Data, images and short clips can be discussed online and, if necessary, adapted in morphological details and motion-style to better represent the cephalopod animal. PMID:24850976

  9. Computed 3D visualisation of an extinct cephalopod using computer tomographs

    NASA Astrophysics Data System (ADS)

    Lukeneder, Alexander

    2012-08-01

    The first 3D visualisation of a heteromorph cephalopod species from the Southern Alps (Dolomites, northern Italy) is presented. Computed tomography, palaeontological data and 3D reconstructions were included in the production of a movie, which shows a life reconstruction of the extinct organism. This detailed reconstruction is according to the current knowledge of the shape and mode of life as well as habitat of this animal. The results are based on the most complete shell known thus far of the genus Dissimilites. Object-based combined analyses from computed tomography and various computed 3D facility programmes help to understand morphological details as well as their ontogentical changes in fossil material. In this study, an additional goal was to show changes in locomotion during different ontogenetic phases of such fossil, marine shell-bearing animals (ammonoids). Hence, the presented models and tools can serve as starting points for discussions on morphology and locomotion of extinct cephalopods in general, and of the genus Dissimilites in particular. The heteromorph ammonoid genus Dissimilites is interpreted here as an active swimmer of the Tethyan Ocean. This study portrays non-destructive methods of 3D visualisation applied on palaeontological material, starting with computed tomography resulting in animated, high-quality video clips. The here presented 3D geometrical models and animation, which are based on palaeontological material, demonstrate the wide range of applications, analytical techniques and also outline possible limitations of 3D models in earth sciences and palaeontology. The realistic 3D models and motion pictures can easily be shared amongst palaeontologists. Data, images and short clips can be discussed online and, if necessary, adapted in morphological details and motion-style to better represent the cephalopod animal.

  10. Wide-angle display developments by computer graphics

    NASA Technical Reports Server (NTRS)

    Fetter, William A.

    1989-01-01

    Computer graphics can now expand its new subset, wide-angle projection, to be as significant a generic capability as computer graphics itself. Some prior work in computer graphics is presented which leads to an attractive further subset of wide-angle projection, called hemispheric projection, to be a major communication media. Hemispheric film systems have long been present and such computer graphics systems are in use in simulators. This is the leading edge of capabilities which should ultimately be as ubiquitous as CRTs (cathode-ray tubes). These assertions are not from degrees in science or only from a degree in graphic design, but in a history of computer graphics innovations, laying groundwork by demonstration. The author believes that it is timely to look at several development strategies, since hemispheric projection is now at a point comparable to the early stages of computer graphics, requiring similar patterns of development again.

  11. Novel low-cost 2D/3D switchable autostereoscopic system for notebook computers and other portable devices

    NASA Astrophysics Data System (ADS)

    Eichenlaub, Jesse B.

    1995-03-01

    Mounting a lenticular lens in front of a flat panel display is a well known, inexpensive, and easy way to create an autostereoscopic system. Such a lens produces half resolution 3D images because half the pixels on the LCD are seen by the left eye and half by the right eye. This may be acceptable for graphics, but it makes full resolution text, as displayed by common software, nearly unreadable. Very fine alignment tolerances normally preclude the possibility of removing and replacing the lens in order to switch between 2D and 3D applications. Lenticular lens based displays are therefore limited to use as dedicated 3D devices. DTI has devised a technique which removes this limitation, allowing switching between full resolution 2D and half resolution 3D imaging modes. A second element, in the form of a concave lenticular lens array whose shape is exactly the negative of the first lens, is mounted on a hinge so that it can be swung down over the first lens array. When so positioned the two lenses cancel optically, allowing the user to see full resolution 2D for text or numerical applications. The two lenses, having complementary shapes, naturally tend to nestle together and snap into perfect alignment when pressed together--thus obviating any need for user operated alignment mechanisms. This system represents an ideal solution for laptop and notebook computer applications. It was devised to meet the stringent requirements of a laptop computer manufacturer including very compact size, very low cost, little impact on existing manufacturing or assembly procedures, and compatibility with existing full resolution 2D text- oriented software as well as 3D graphics. Similar requirements apply to high and electronic calculators, several models of which now use LCDs for the display of graphics.

  12. The Basic Concepts of Three-Dimensional Computer Graphics for Artists.

    ERIC Educational Resources Information Center

    Sachter, Judy E.

    Arguing that an artist using any new medium must understand its techniques and limitations, this master's thesis is intended to demystify state-of-the-art 3-D computer graphics through a discussion of the technical literature from the artist's point of view and an analysis of the curricular needs of the artist. The first of six chapters discusses…

  13. Assemble: an interactive graphical tool to analyze and build RNA architectures at the 2D and 3D levels.

    PubMed

    Jossinet, Fabrice; Ludwig, Thomas E; Westhof, Eric

    2010-08-15

    Assemble is an intuitive graphical interface to analyze, manipulate and build complex 3D RNA architectures. It provides several advanced and unique features within the framework of a semi-automated modeling process that can be performed by homology and ab initio with or without electron density maps. Those include the interactive editing of a secondary structure and a searchable, embedded library of annotated tertiary structures. Assemble helps users with performing recurrent and otherwise tedious tasks in structural RNA research. Assemble is released under an open-source license (MIT license) and is freely available at http://bioinformatics.org/assemble. It is implemented in the Java language and runs on MacOSX, Linux and Windows operating systems.

  14. Graphical interface for the physics-based generation of inputs to 3D MEEC SGEMP and SREMP simulations

    SciTech Connect

    Bland, M; Wondra, J; Nunan, S; Walters, D

    1998-12-01

    A graphical user interface (GUI) is under development for the MEEC family of SGEMP and SREMP simulation codes. These codes are workhorse legacy codes that have been in use for nearly two decades, with modifications and enhanced physics models added throughout the years. The MEEC codes are currently being evaluated for use by the DOE in the Dual Revalidation program and experiments at NIF. The new GUI makes the codes more accessible and less prone to input errors by automatically generating the parameters and grids that previously had to be designed by hand. physics-based algorithms define the simulation volume with expanding meshes. Users are able to specify objects, materials, and emission surfaces through dialogs and input boxes. 3D and orthographic views are available to view objects in the volume. Zone slice views are available for stepping through the overlay of objects on the mesh in planes aligned with the primary axes.

  15. Graphical interface for the physics-based generation of inputs to 3D MEEC SGEMP and SREMP simulations

    SciTech Connect

    Bland, M; Walters, D; Wondra, J

    1999-06-01

    A graphical user interface (GUI) is under development for the MEEC family of SGEMP and SREMP simulation codes [1,2]. These codes are ''workhorse'' legacy codes that have been in use for nearly two decades, with modifications and enhanced physics models added throughout the years. The MEEC codes are currently being evaluated for use by the DOE in the Dual Revalidation Program and experiments at NIF. The new GUI makes the codes more accessible and less prone to input errors by automatically generating the parameters and grids that previously had to be designed ''by hand''. Physics-based algorithms define the simulation volume with expanding meshes. Users are able to specify objects, materials, and emission surfaces through dialogs and input boxes. 3D and orthographic views are available to view objects in the volume. Zone slice views are available for stepping through the overlay of objects on the mesh in planes aligned with the primary axes.

  16. GeoBuilder: a geometric algorithm visualization and debugging system for 2D and 3D geometric computing.

    PubMed

    Wei, Jyh-Da; Tsai, Ming-Hung; Lee, Gen-Cher; Huang, Jeng-Hung; Lee, Der-Tsai

    2009-01-01

    Algorithm visualization is a unique research topic that integrates engineering skills such as computer graphics, system programming, database management, computer networks, etc., to facilitate algorithmic researchers in testing their ideas, demonstrating new findings, and teaching algorithm design in the classroom. Within the broad applications of algorithm visualization, there still remain performance issues that deserve further research, e.g., system portability, collaboration capability, and animation effect in 3D environments. Using modern technologies of Java programming, we develop an algorithm visualization and debugging system, dubbed GeoBuilder, for geometric computing. The GeoBuilder system features Java's promising portability, engagement of collaboration in algorithm development, and automatic camera positioning for tracking 3D geometric objects. In this paper, we describe the design of the GeoBuilder system and demonstrate its applications.

  17. SPACEBAR: Kinematic design by computer graphics

    NASA Technical Reports Server (NTRS)

    Ricci, R. J.

    1975-01-01

    The interactive graphics computer program SPACEBAR, conceived to reduce the time and complexity associated with the development of kinematic mechanisms on the design board, was described. This program allows the direct design and analysis of mechanisms right at the terminal screen. All input variables, including linkage geometry, stiffness, and applied loading conditions, can be fed into or changed at the terminal and may be displayed in three dimensions. All mechanism configurations can be cycled through their range of travel and viewed in their various geometric positions. Output data includes geometric positioning in orthogonal coordinates of each node point in the mechanism, velocity and acceleration of the node points, and internal loads and displacements of the node points and linkages. All analysis calculations take at most a few seconds to complete. Output data can be viewed at the scope and also printed at the discretion of the user.

  18. Decluttering Methods for Computer-Generated Graphic Displays

    NASA Technical Reports Server (NTRS)

    Schultz, E. Eugene, Jr.

    1986-01-01

    Symbol simplification and contrasting enhance viewer's ability to detect particular symbol. Report describes experiments designed to indicate how various decluttering methods affect viewer's abilities to distinguish essential from nonessential features on computer-generated graphic displays. Results indicate partial removal of nonessential graphic features through symbol simplification effective in decluttering as total removal of nonessential graphic features.

  19. 3-D Signal Processing in a Computer Vision System

    Treesearch

    Dongping Zhu; Richard W. Conners; Philip A. Araman

    1991-01-01

    This paper discusses the problem of 3-dimensional image filtering in a computer vision system that would locate and identify internal structural failure. In particular, a 2-dimensional adaptive filter proposed by Unser has been extended to 3-dimension. In conjunction with segmentation and labeling, the new filter has been used in the computer vision system to...

  20. General aviation design synthesis utilizing interactive computer graphics

    NASA Technical Reports Server (NTRS)

    Galloway, T. L.; Smith, M. R.

    1976-01-01

    Interactive computer graphics is a fast growing area of computer application, due to such factors as substantial cost reductions in hardware, general availability of software, and expanded data communication networks. In addition to allowing faster and more meaningful input/output, computer graphics permits the use of data in graphic form to carry out parametric studies for configuration selection and for assessing the impact of advanced technologies on general aviation designs. The incorporation of interactive computer graphics into a NASA developed general aviation synthesis program is described, and the potential uses of the synthesis program in preliminary design are demonstrated.

  1. Computer-assisted three-dimensional surgical planning and simulation: 3D virtual osteotomy.

    PubMed

    Xia, J; Ip, H H; Samman, N; Wang, D; Kot, C S; Yeung, R W; Tideman, H

    2000-02-01

    A computer-assisted three-dimensional virtual osteotomy system for orthognathic surgery (CAVOS) is presented. The virtual reality workbench is used for surgical planning. The surgeon immerses in a virtual reality environment with stereo eyewear, holds a virtual "scalpel" (3D Mouse) and operates on a "real" patient (3D visualization) to obtain pre-surgical prediction (3D bony segment movements). Virtual surgery on a computer-generated 3D head model is simulated and can be visualized from any arbitrary viewing point in a personal computer system.

  2. 3D printing meets computational astrophysics: deciphering the structure of η Carinae's inner colliding winds

    NASA Astrophysics Data System (ADS)

    Madura, T. I.; Clementel, N.; Gull, T. R.; Kruip, C. J. H.; Paardekooper, J.-P.

    2015-06-01

    We present the first 3D prints of output from a supercomputer simulation of a complex astrophysical system, the colliding stellar winds in the massive (≳120 M⊙), highly eccentric (e ˜ 0.9) binary star system η Carinae. We demonstrate the methodology used to incorporate 3D interactive figures into a PDF (Portable Document Format) journal publication and the benefits of using 3D visualization and 3D printing as tools to analyse data from multidimensional numerical simulations. Using a consumer-grade 3D printer (MakerBot Replicator 2X), we successfully printed 3D smoothed particle hydrodynamics simulations of η Carinae's inner (r ˜ 110 au) wind-wind collision interface at multiple orbital phases. The 3D prints and visualizations reveal important, previously unknown `finger-like' structures at orbital phases shortly after periastron (φ ˜ 1.045) that protrude radially outwards from the spiral wind-wind collision region. We speculate that these fingers are related to instabilities (e.g. thin-shell, Rayleigh-Taylor) that arise at the interface between the radiatively cooled layer of dense post-shock primary-star wind and the fast (3000 km s-1), adiabatic post-shock companion-star wind. The success of our work and easy identification of previously unrecognized physical features highlight the important role 3D printing and interactive graphics can play in the visualization and understanding of complex 3D time-dependent numerical simulations of astrophysical phenomena.

  3. GPU-enabled FREALIGN: Accelerating single particle 3D reconstruction and refinement in Fourier space on graphics processors

    PubMed Central

    Li, Xueming; Grigorieff, Nikolaus; Cheng, Yifan

    2010-01-01

    Among all the factors that determine the resolution of a three-dimensional reconstruction by single particle electron cryo-microscopy (cryoEM), the number of particle images used in the dataset plays a major role. More images generally yield better resolution, assuming the imaged protein complex is conformationally and compositionally homogeneous. To facilitate processing of very large datasets, we modified the computer program, FREALIGN, to execute the computationally most intensive procedures on Graphics Processing Units (GPUs). Using the modified program, the execution speed increased between 10 and 240-fold depending on the task performed by FREALIGN. Here we report the steps necessary to parallelize critical FREALIGN subroutines and evaluate its performance on computers with multiple GPUs. PMID:20558298

  4. The 3d International Workshop on Computational Electronics

    NASA Astrophysics Data System (ADS)

    Goodnick, Stephen M.

    1994-09-01

    The Third International Workshop on Computational Electronics (IWCE) was held at the Benson Hotel in downtown Portland, Oregon, on May 18, 19, and 20, 1994. The workshop was devoted to a broad range of topics in computational electronics related to the simulation of electronic transport in semiconductors and semiconductor devices, particularly those which use large computational resources. The workshop was supported by the National Science Foundation (NSF), the Office of Naval Research and the Army Research Office, as well as local support from the Oregon Joint Graduate Schools of Engineering and the Oregon Center for Advanced Technology Education. There were over 100 participants in the Portland workshop, of which more than one quarter represented research groups outside of the United States from Austria, Canada, France, Germany, Italy, Japan, Switzerland, and the United Kingdom. There were a total 81 papers presented at the workshop, 9 invited talks, 26 oral presentations and 46 poster presentations. The emphasis of the contributions reflected the interdisciplinary nature of computational electronics with researchers from the Chemistry, Computer Science, Mathematics, Engineering, and Physics communities participating in the workshop.

  5. Three Dimensional Computer Graphics Federates for the 2012 Smackdown Simulation

    NASA Technical Reports Server (NTRS)

    Fordyce, Crystal; Govindaiah, Swetha; Muratet, Sean; O'Neil, Daniel A.; Schricker, Bradley C.

    2012-01-01

    The Simulation Interoperability Standards Organization (SISO) Smackdown is a two-year old annual event held at the 2012 Spring Simulation Interoperability Workshop (SIW). A primary objective of the Smackdown event is to provide college students with hands-on experience in developing distributed simulations using High Level Architecture (HLA). Participating for the second time, the University of Alabama in Huntsville (UAHuntsville) deployed four federates, two federates simulated a communications server and a lunar communications satellite with a radio. The other two federates generated 3D computer graphics displays for the communication satellite constellation and for the surface based lunar resupply mission. Using the Light-Weight Java Graphics Library, the satellite display federate presented a lunar-texture mapped sphere of the moon and four Telemetry Data Relay Satellites (TDRS), which received object attributes from the lunar communications satellite federate to drive their motion. The surface mission display federate was an enhanced version of the federate developed by ForwardSim, Inc. for the 2011 Smackdown simulation. Enhancements included a dead-reckoning algorithm and a visual indication of which communication satellite was in line of sight of Hadley Rille. This paper concentrates on these two federates by describing the functions, algorithms, HLA object attributes received from other federates, development experiences and recommendations for future, participating Smackdown teams.

  6. Fast crustal deformation computing method for multiple computations accelerated by a graphics processing unit cluster

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Takuma; Ichimura, Tsuyoshi; Yagi, Yuji; Agata, Ryoichiro; Hori, Takane; Hori, Muneo

    2017-08-01

    As high-resolution observational data become more common, the demand for numerical simulations of crustal deformation using 3-D high-fidelity modelling is increasing. To increase the efficiency of performing numerical simulations with high computation costs, we developed a fast solver using heterogeneous computing, with graphics processing units (GPUs) and central processing units, and then used the solver in crustal deformation computations. The solver was based on an iterative solver and was devised so that a large proportion of the computation was calculated more quickly using GPUs. To confirm the utility of the proposed solver, we demonstrated a numerical simulation of the coseismic slip distribution estimation, which requires 360 000 crustal deformation computations with 82 196 106 degrees of freedom.

  7. Computer graphics application in the engineering design integration system

    NASA Technical Reports Server (NTRS)

    Glatt, C. R.; Abel, R. W.; Hirsch, G. N.; Alford, G. E.; Colquitt, W. N.; Stewart, W. A.

    1975-01-01

    The computer graphics aspect of the Engineering Design Integration (EDIN) system and its application to design problems were discussed. Three basic types of computer graphics may be used with the EDIN system for the evaluation of aerospace vehicles preliminary designs: offline graphics systems using vellum-inking or photographic processes, online graphics systems characterized by direct coupled low cost storage tube terminals with limited interactive capabilities, and a minicomputer based refresh terminal offering highly interactive capabilities. The offline line systems are characterized by high quality (resolution better than 0.254 mm) and slow turnaround (one to four days). The online systems are characterized by low cost, instant visualization of the computer results, slow line speed (300 BAUD), poor hard copy, and the early limitations on vector graphic input capabilities. The recent acquisition of the Adage 330 Graphic Display system has greatly enhanced the potential for interactive computer aided design.

  8. Computational 3-D Model of the Human Respiratory System

    EPA Science Inventory

    We are developing a comprehensive, morphologically-realistic computational model of the human respiratory system that can be used to study the inhalation, deposition, and clearance of contaminants, while being adaptable for age, race, gender, and health/disease status. The model ...

  9. Modeling Computer Communication Networks in a Realistic 3D Environment

    DTIC Science & Technology

    2010-03-01

    5 2.1.3 Animated Visualization . . . . . . . . . . . . . . 6 2.1.4 Visualization and Computer Networks . . . . . 7 2.2 Current...32 3.1.4 Network Connectivity . . . . . . . . . . . . . . . 33 vi Page 3.1.5 Network Traffic Animation ...55 4.1.5 Network Traffic Animation . . . . . . . . . . . . 55 4.1.6 Scene Control . . . . . . . . . . . . . . . . . . . 58 4.1.7

  10. Computational 3-D Model of the Human Respiratory System

    EPA Science Inventory

    We are developing a comprehensive, morphologically-realistic computational model of the human respiratory system that can be used to study the inhalation, deposition, and clearance of contaminants, while being adaptable for age, race, gender, and health/disease status. The model ...

  11. Non-Fourier Computer Generated Holography for 3-D Display

    DTIC Science & Technology

    1989-11-01

    Captain Sean Kelly, AFSC WRDC/KTD, for his contribution of technical information. Last, I wish to thank my wife Debbie, and my children Karen and Benjamin...I I I 44 i I+ I- Fiue1.WvlntIn mltd I4 Bibliography 1. Barakat, R., et al. The Computer in Optical Reasearch : Methods and Applica- tions. Berlin

  12. Computational ocean acoustics: Advances in 3D ocean acoustic modeling

    NASA Astrophysics Data System (ADS)

    Schmidt, Henrik; Jensen, Finn B.

    2012-11-01

    The numerical model of ocean acoustic propagation developed in the 1980's are still in widespread use today, and the field of computational ocean acoustics is often considered a mature field. However, the explosive increase in computational power available to the community has created opportunities for modeling phenomena that earlier were beyond reach. Most notably, three-dimensional propagation and scattering problems have been prohibitive computationally, but are now addressed routinely using brute force numerical approaches such as the Finite Element Method, in particular for target scattering problems, where they are being combined with the traditional wave theory propagation models in hybrid modeling frameworks. Also, recent years has seen the development of hybrid approaches coupling oceanographic circulation models with acoustic propagation models, enabling the forecasting of sonar performance uncertainty in dynamic ocean environments. These and other advances made over the last couple of decades support the notion that the field of computational ocean acoustics is far from being mature. [Work supported by the Office of Naval Research, Code 321OA].

  13. Computation of tooth axes of existent and missing teeth from 3D CT images.

    PubMed

    Wang, Yang; Wu, Lin; Guo, Huayan; Qiu, Tiantian; Huang, Yuanliang; Lin, Bin; Wang, Lisheng

    2015-12-01

    Orientations of tooth axes are important quantitative information used in dental diagnosis and surgery planning. However, their computation is a complex problem, and the existing methods have respective limitations. This paper proposes new methods to compute 3D tooth axes from 3D CT images for existent teeth with single root or multiple roots and to estimate 3D tooth axes from 3D CT images for missing teeth. The tooth axis of a single-root tooth will be determined by segmenting the pulp cavity of the tooth and computing the principal direction of the pulp cavity, and the estimation of tooth axes of the missing teeth is modeled as an interpolation problem of some quaternions along a 3D curve. The proposed methods can either avoid the difficult teeth segmentation problem or improve the limitations of existing methods. Their effectiveness and practicality are demonstrated by experimental results of different 3D CT images from the clinic.

  14. Simplification of 3D Graphics for Mobile Devices: Exploring the Trade-off Between Energy Savings and User Perceptions of Visual Quality

    NASA Astrophysics Data System (ADS)

    Vatjus-Anttila, Jarkko; Koskela, Timo; Lappalainen, Tuomas; Häkkilä, Jonna

    2017-03-01

    3D graphics have quickly become a popular form of media that can also be accessed with today's mobile devices. However, the use of 3D applications with mobile devices is typically a very energy-consuming task due to the processing complexity and the large file size of 3D graphics. As a result, their use may lead to rapid depletion of the limited battery life. In this paper, we investigate how much energy savings can be gained in the transmission and rendering of 3D graphics by simplifying geometry data. In this connection, we also examine users' perceptions on the visual quality of the simplified 3D models. The results of this paper provide new knowledge on the energy savings that can be gained through geometry simplification, as well as on how much the geometry can be simplified before the visual quality of 3D models becomes unacceptable for the mobile users. Based on the results, it can be concluded that geometry simplification can provide significant energy savings for mobile devices without disturbing the users. When geometry simplification is combined with distance based adjustment of detail, up to 52% energy savings were gained in our experiments compared to using only a single high quality 3D model.

  15. Educational Concepts of Computer Graphics in the Classroom.

    ERIC Educational Resources Information Center

    Smith, Alan D.

    There are increasing numbers of commercially available computer graphics packages, both in terms of hardware and software, that can be utilized by instructors, practitioners, and students of education. With the proliferation of low-cost graphic terminals, time-sharing capabilities, and recent advances in mini- and microcomputers, computer graphics…

  16. Graphical User Interface Programming in Introductory Computer Science.

    ERIC Educational Resources Information Center

    Skolnick, Michael M.; Spooner, David L.

    Modern computing systems exploit graphical user interfaces for interaction with users; as a result, introductory computer science courses must begin to teach the principles underlying such interfaces. This paper presents an approach to graphical user interface (GUI) implementation that is simple enough for beginning students to understand, yet…

  17. Computer Graphics for Student Engagement in Science Learning.

    ERIC Educational Resources Information Center

    Cifuentes, Lauren; Hsieh, Yi-Chuan Jane

    2001-01-01

    Discusses student use of computer graphics software and presents documentation from a visualization workshop designed to help learners use computer graphics to construct meaning while they studied science concepts. Describes problems and benefits when delivering visualization workshops in the natural setting of a middle school. (Author/LRW)

  18. PLOT3D/AMES, APOLLO UNIX VERSION USING GMR3D (WITH TURB3D)

    NASA Technical Reports Server (NTRS)

    Buning, P.

    1994-01-01

    PLOT3D is an interactive graphics program designed to help scientists visualize computational fluid dynamics (CFD) grids and solutions. Today, supercomputers and CFD algorithms can provide scientists with simulations of such highly complex phenomena that obtaining an understanding of the simulations has become a major problem. Tools which help the scientist visualize the simulations can be of tremendous aid. PLOT3D/AMES offers more functions and features, and has been adapted for more types of computers than any other CFD graphics program. Version 3.6b+ is supported for five computers and graphic libraries. Using PLOT3D, CFD physicists can view their computational models from any angle, observing the physics of problems and the quality of solutions. As an aid in designing aircraft, for example, PLOT3D's interactive computer graphics can show vortices, temperature, reverse flow, pressure, and dozens of other characteristics of air flow during flight. As critical areas become obvious, they can easily be studied more closely using a finer grid. PLOT3D is part of a computational fluid dynamics software cycle. First, a program such as 3DGRAPE (ARC-12620) helps the scientist generate computational grids to model an object and its surrounding space. Once the grids have been designed and parameters such as the angle of attack, Mach number, and Reynolds number have been specified, a "flow-solver" program such as INS3D (ARC-11794 or COS-10019) solves the system of equations governing fluid flow, usually on a supercomputer. Grids sometimes have as many as two million points, and the "flow-solver" produces a solution file which contains density, x- y- and z-momentum, and stagnation energy for each grid point. With such a solution file and a grid file containing up to 50 grids as input, PLOT3D can calculate and graphically display any one of 74 functions, including shock waves, surface pressure, velocity vectors, and particle traces. PLOT3D's 74 functions are organized into

  19. PLOT3D/AMES, APOLLO UNIX VERSION USING GMR3D (WITHOUT TURB3D)

    NASA Technical Reports Server (NTRS)

    Buning, P.

    1994-01-01

    PLOT3D is an interactive graphics program designed to help scientists visualize computational fluid dynamics (CFD) grids and solutions. Today, supercomputers and CFD algorithms can provide scientists with simulations of such highly complex phenomena that obtaining an understanding of the simulations has become a major problem. Tools which help the scientist visualize the simulations can be of tremendous aid. PLOT3D/AMES offers more functions and features, and has been adapted for more types of computers than any other CFD graphics program. Version 3.6b+ is supported for five computers and graphic libraries. Using PLOT3D, CFD physicists can view their computational models from any angle, observing the physics of problems and the quality of solutions. As an aid in designing aircraft, for example, PLOT3D's interactive computer graphics can show vortices, temperature, reverse flow, pressure, and dozens of other characteristics of air flow during flight. As critical areas become obvious, they can easily be studied more closely using a finer grid. PLOT3D is part of a computational fluid dynamics software cycle. First, a program such as 3DGRAPE (ARC-12620) helps the scientist generate computational grids to model an object and its surrounding space. Once the grids have been designed and parameters such as the angle of attack, Mach number, and Reynolds number have been specified, a "flow-solver" program such as INS3D (ARC-11794 or COS-10019) solves the system of equations governing fluid flow, usually on a supercomputer. Grids sometimes have as many as two million points, and the "flow-solver" produces a solution file which contains density, x- y- and z-momentum, and stagnation energy for each grid point. With such a solution file and a grid file containing up to 50 grids as input, PLOT3D can calculate and graphically display any one of 74 functions, including shock waves, surface pressure, velocity vectors, and particle traces. PLOT3D's 74 functions are organized into

  20. PLOT3D/AMES, APOLLO UNIX VERSION USING GMR3D (WITHOUT TURB3D)

    NASA Technical Reports Server (NTRS)

    Buning, P.

    1994-01-01

    PLOT3D is an interactive graphics program designed to help scientists visualize computational fluid dynamics (CFD) grids and solutions. Today, supercomputers and CFD algorithms can provide scientists with simulations of such highly complex phenomena that obtaining an understanding of the simulations has become a major problem. Tools which help the scientist visualize the simulations can be of tremendous aid. PLOT3D/AMES offers more functions and features, and has been adapted for more types of computers than any other CFD graphics program. Version 3.6b+ is supported for five computers and graphic libraries. Using PLOT3D, CFD physicists can view their computational models from any angle, observing the physics of problems and the quality of solutions. As an aid in designing aircraft, for example, PLOT3D's interactive computer graphics can show vortices, temperature, reverse flow, pressure, and dozens of other characteristics of air flow during flight. As critical areas become obvious, they can easily be studied more closely using a finer grid. PLOT3D is part of a computational fluid dynamics software cycle. First, a program such as 3DGRAPE (ARC-12620) helps the scientist generate computational grids to model an object and its surrounding space. Once the grids have been designed and parameters such as the angle of attack, Mach number, and Reynolds number have been specified, a "flow-solver" program such as INS3D (ARC-11794 or COS-10019) solves the system of equations governing fluid flow, usually on a supercomputer. Grids sometimes have as many as two million points, and the "flow-solver" produces a solution file which contains density, x- y- and z-momentum, and stagnation energy for each grid point. With such a solution file and a grid file containing up to 50 grids as input, PLOT3D can calculate and graphically display any one of 74 functions, including shock waves, surface pressure, velocity vectors, and particle traces. PLOT3D's 74 functions are organized into

  1. PLOT3D/AMES, APOLLO UNIX VERSION USING GMR3D (WITH TURB3D)

    NASA Technical Reports Server (NTRS)

    Buning, P.

    1994-01-01

    PLOT3D is an interactive graphics program designed to help scientists visualize computational fluid dynamics (CFD) grids and solutions. Today, supercomputers and CFD algorithms can provide scientists with simulations of such highly complex phenomena that obtaining an understanding of the simulations has become a major problem. Tools which help the scientist visualize the simulations can be of tremendous aid. PLOT3D/AMES offers more functions and features, and has been adapted for more types of computers than any other CFD graphics program. Version 3.6b+ is supported for five computers and graphic libraries. Using PLOT3D, CFD physicists can view their computational models from any angle, observing the physics of problems and the quality of solutions. As an aid in designing aircraft, for example, PLOT3D's interactive computer graphics can show vortices, temperature, reverse flow, pressure, and dozens of other characteristics of air flow during flight. As critical areas become obvious, they can easily be studied more closely using a finer grid. PLOT3D is part of a computational fluid dynamics software cycle. First, a program such as 3DGRAPE (ARC-12620) helps the scientist generate computational grids to model an object and its surrounding space. Once the grids have been designed and parameters such as the angle of attack, Mach number, and Reynolds number have been specified, a "flow-solver" program such as INS3D (ARC-11794 or COS-10019) solves the system of equations governing fluid flow, usually on a supercomputer. Grids sometimes have as many as two million points, and the "flow-solver" produces a solution file which contains density, x- y- and z-momentum, and stagnation energy for each grid point. With such a solution file and a grid file containing up to 50 grids as input, PLOT3D can calculate and graphically display any one of 74 functions, including shock waves, surface pressure, velocity vectors, and particle traces. PLOT3D's 74 functions are organized into

  2. Building a 3D Computed Tomography Scanner From Surplus Parts.

    PubMed

    Haidekker, Mark A

    2014-01-01

    Computed tomography (CT) scanners are expensive imaging devices, often out of reach for small research groups. Designing and building a CT scanner from modular components is possible, and this article demonstrates that realization of a CT scanner from components is surprisingly easy. However, the high costs of a modular X-ray source and detector limit the overall cost savings. In this article, the possibility of building a CT scanner with available surplus X-ray parts is discussed, and a practical device is described that incurred costs of less than $16,000. The image quality of this device is comparable with commercial devices. The disadvantage is that design constraints imposed by the available components lead to slow scan speeds and a resolution of 0.5 mm. Despite these limitations, a device such as this is attractive for imaging studies in the biological and biomedical sciences, as well as for advancing CT technology itself.

  3. Teaching 3D computer animation to illustrators: the instructor as translator and technical director.

    PubMed

    Koning, Wobbe F

    2012-01-01

    An art instructor discusses the difficulties he's encountered teaching computer graphics skills to undergraduate art students. To help the students, he introduced an automated-rigging script for character animation.

  4. GEO3D - Three-Dimensional Computer Model of a Ground Source Heat Pump System

    SciTech Connect

    James Menart

    2013-06-07

    This file is the setup file for the computer program GEO3D. GEO3D is a computer program written by Jim Menart to simulate vertical wells in conjunction with a heat pump for ground source heat pump (GSHP) systems. This is a very detailed three-dimensional computer model. This program produces detailed heat transfer and temperature field information for a vertical GSHP system.

  5. A Fast Full Tensor Gravity computation algorithm for High Resolution 3D Geologic Interpretations

    NASA Astrophysics Data System (ADS)

    Jayaram, V.; Crain, K.; Keller, G. R.

    2011-12-01

    We present an algorithm to rapidly calculate the vertical gravity and full tensor gravity (FTG) values due to a 3-D geologic model. This algorithm can be implemented on single, multi-core CPU and graphical processing units (GPU) architectures. Our technique is based on the line element approximation with a constant density within each grid cell. This type of parameterization is well suited for high-resolution elevation datasets with grid size typically in the range of 1m to 30m. The large high-resolution data grids in our studies employ a pre-filtered mipmap pyramid type representation for the grid data known as the Geometry clipmap. The clipmap was first introduced by Microsoft Research in 2004 to do fly-through terrain visualization. This method caches nested rectangular extents of down-sampled data layers in the pyramid to create view-dependent calculation scheme. Together with the simple grid structure, this allows the gravity to be computed conveniently on-the-fly, or stored in a highly compressed format. Neither of these capabilities has previously been available. Our approach can perform rapid calculations on large topographies including crustal-scale models derived from complex geologic interpretations. For example, we used a 1KM Sphere model consisting of 105000 cells at 10m resolution with 100000 gravity stations. The line element approach took less than 90 seconds to compute the FTG and vertical gravity on an Intel Core i7 CPU at 3.07 GHz utilizing just its single core. Also, unlike traditional gravity computational algorithms, the line-element approach can calculate gravity effects at locations interior or exterior to the model. The only condition that must be met is the observation point cannot be located directly above the line element. Therefore, we perform a location test and then apply appropriate formulation to those data points. We will present and compare the computational performance of the traditional prism method versus the line element

  6. Segmentation of 3D ultrasound computer tomography reflection images using edge detection and surface fitting

    NASA Astrophysics Data System (ADS)

    Hopp, T.; Zapf, M.; Ruiter, N. V.

    2014-03-01

    An essential processing step for comparison of Ultrasound Computer Tomography images to other modalities, as well as for the use in further image processing, is to segment the breast from the background. In this work we present a (semi-) automated 3D segmentation method which is based on the detection of the breast boundary in coronal slice images and a subsequent surface fitting. The method was evaluated using a software phantom and in-vivo data. The fully automatically processed phantom results showed that a segmentation of approx. 10% of the slices of a dataset is sufficient to recover the overall breast shape. Application to 16 in-vivo datasets was performed successfully using semi-automated processing, i.e. using a graphical user interface for manual corrections of the automated breast boundary detection. The processing time for the segmentation of an in-vivo dataset could be significantly reduced by a factor of four compared to a fully manual segmentation. Comparison to manually segmented images identified a smoother surface for the semi-automated segmentation with an average of 11% of differing voxels and an average surface deviation of 2mm. Limitations of the edge detection may be overcome by future updates of the KIT USCT system, allowing a fully-automated usage of our segmentation approach.

  7. Computer-Assisted 3D Kinematic Analysis of All Leg Joints in Walking Insects

    PubMed Central

    Bender, John A.; Simpson, Elaine M.; Ritzmann, Roy E.

    2010-01-01

    High-speed video can provide fine-scaled analysis of animal behavior. However, extracting behavioral data from video sequences is a time-consuming, tedious, subjective task. These issues are exacerbated where accurate behavioral descriptions require analysis of multiple points in three dimensions. We describe a new computer program written to assist a user in simultaneously extracting three-dimensional kinematics of multiple points on each of an insect's six legs. Digital video of a walking cockroach was collected in grayscale at 500 fps from two synchronized, calibrated cameras. We improved the legs' visibility by painting white dots on the joints, similar to techniques used for digitizing human motion. Compared to manual digitization of 26 points on the legs over a single, 8-second bout of walking (or 106,496 individual 3D points), our software achieved approximately 90% of the accuracy with 10% of the labor. Our experimental design reduced the complexity of the tracking problem by tethering the insect and allowing it to walk in place on a lightly oiled glass surface, but in principle, the algorithms implemented are extensible to free walking. Our software is free and open-source, written in the free language Python and including a graphical user interface for configuration and control. We encourage collaborative enhancements to make this tool both better and widely utilized. PMID:21049024

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

    PubMed

    Uchida, Masafumi

    2014-04-01

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

  9. Computation and graphics in mathematical research

    SciTech Connect

    Hoffman, D.A.; Spruck, J.

    1992-08-13

    This report discusses: The description of the GANG Project and results for prior research; the center for geometry, analysis, numerics and graphics; description of GANG Laboratory; software development at GANG; and mathematical and scientific research activities.

  10. 3D-brain 2.0--narrowing the gap between personal computers and high end workstations.

    PubMed

    Kling-Petersen, T; Pascher, R; Rydmark, M

    1998-01-01

    Recent advances in personal computer hardware and software have pushed the graphic capacity of these easier to use and, more importantly, cheaper computers to a level approximating the current standard of high end workstations. The interactivity and graphic complexity of a modern PC is rapidly approaching the current standard on Silicon Graphics (although with respect to texture mapping, the SGI is still ahead of the PCs). The modern medical student laboring under increasingly higher demands with respect to versatility, not only in basic science and traditional medical knowledge, is also faced with the requirement to learn and understand modern scientific visualization and analytical instruments. Furthermore, basic knowledge of information technology and computer literacy is expected of the next generation medical professionals. These demands forces medical schools to increasingly invest in computers and information technology for educational purposes. Due to common class sizes, these computers are most commonly Windows PCs or Apple Macintoshes. For distance education, telematics or studies at home, personal computer versions of the workstation graphics are a necessity. 3D-Brain 2.0 is an educational software package intended to run on basic personal computers and utilizing modern software technologies such as QuickTime VR 2.0 and VRML 2.0, to provide the students with insight into modern clinical and scientific visualization, focusing on the anatomy and functionality of the human brain. The aim of this paper to test the validity and usefulness of these new visualization techniques. 3D-Brain is based on human brains sliced in 1 mm sections (NB. NOT based on NLMs Visual Human). Each slice was photographed, digitized, optimized and aligned using proprietary software. The datasets were then created by manual tracing followed by triangulation, smoothing and 3D visualization using Silicon Graphics computers. For the QuickTime VR project, 684 images with a 10 degrees

  11. A modern approach to storing of 3D geometry of objects in machine engineering industry

    NASA Astrophysics Data System (ADS)

    Sokolova, E. A.; Aslanov, G. A.; Sokolov, A. A.

    2017-02-01

    3D graphics is a kind of computer graphics which has absorbed a lot from the vector and raster computer graphics. It is used in interior design projects, architectural projects, advertising, while creating educational computer programs, movies, visual images of parts and products in engineering, etc. 3D computer graphics allows one to create 3D scenes along with simulation of light conditions and setting up standpoints.

  12. A new strategic neurosurgical planning tool for brainstem cavernous malformations using interactive computer graphics with multimodal fusion images.

    PubMed

    Kin, Taichi; Nakatomi, Hirofumi; Shojima, Masaaki; Tanaka, Minoru; Ino, Kenji; Mori, Harushi; Kunimatsu, Akira; Oyama, Hiroshi; Saito, Nobuhito

    2012-07-01

    In this study, the authors used preoperative simulation employing 3D computer graphics (interactive computer graphics) to fuse all imaging data for brainstem cavernous malformations. The authors evaluated whether interactive computer graphics or 2D imaging correlated better with the actual operative field, particularly in identifying a developmental venous anomaly (DVA). The study population consisted of 10 patients scheduled for surgical treatment of brainstem cavernous malformations. Data from preoperative imaging (MRI, CT, and 3D rotational angiography) were automatically fused using a normalized mutual information method, and then reconstructed by a hybrid method combining surface rendering and volume rendering methods. With surface rendering, multimodality and multithreshold techniques for 1 tissue were applied. The completed interactive computer graphics were used for simulation of surgical approaches and assumed surgical fields. Preoperative diagnostic rates for a DVA associated with brainstem cavernous malformation were compared between conventional 2D imaging and interactive computer graphics employing receiver operating characteristic (ROC) analysis. The time required for reconstruction of 3D images was 3-6 hours for interactive computer graphics. Observation in interactive mode required approximately 15 minutes. Detailed anatomical information for operative procedures, from the craniotomy to microsurgical operations, could be visualized and simulated three-dimensionally as 1 computer graphic using interactive computer graphics. Virtual surgical views were consistent with actual operative views. This technique was very useful for examining various surgical approaches. Mean (±SEM) area under the ROC curve for rate of DVA diagnosis was significantly better for interactive computer graphics (1.000±0.000) than for 2D imaging (0.766±0.091; p<0.001, Mann-Whitney U-test). The authors report a new method for automatic registration of preoperative imaging data

  13. The spine in 3D. Computed tomographic reformation from 2D axial sections.

    PubMed

    Virapongse, C; Gmitro, A; Sarwar, M

    1986-01-01

    A new program (3D83, General Electric) was used to reformat three-dimensional (3D) images from two-dimensional (2D) computed tomographic axial scans in 18 patients who had routine scans of the spine. The 3D spine images were extremely true to life and could be rotated around all three principle axes (constituting a movie), so that an illusion of head-motion parallax was created. The benefit of 3D reformation with this program is primarily for preoperative planning. It appears that 3D can also effectively determine the patency of foraminal stenosis by reformatting in hemisections. Currently this program is subject to several drawbacks that require user interaction and long reconstruction time. With further improvement, 3D reformation will find increasing clinical applicability.

  14. Computer-assisted three-dimensional surgical planning and simulation: 3D color facial model generation.

    PubMed

    Xia, J; Wang, D; Samman, N; Yeung, R W; Tideman, H

    2000-02-01

    A scheme for texture mapping a 3D individualized color photo-realistic facial model from real color portraits and CT data is described. First, 3D CT images including both soft and hard tissues should be reconstructed from sequential CT slices, using a surface rendering technique. Facial features are extracted from 3D soft tissue. A generic mesh is individualized by correspondence matching and interpolation from those feature vertices. Three digitized color portraits with the "third" dimension from reconstructed soft tissue are blended and texture-mapped onto the 3D head model (mesh). A color simulated human head generated from frontal, right and left real color portraits can be viewed from an arbitrary angle in an inexpensive and user-friendly conventional personal computer. This scheme is the basic procedure in 3D computer-assisted simulation surgery.

  15. A low cost computer aided design (CAD) system for 3D-reconstruction from serial sections.

    PubMed

    Keri, C; Ahnelt, P K

    1991-05-01

    This paper describes an approach to computer-assisted 3D-reconstruction of neuronal specimens based on a low cost yet powerful software package for a personal computer (Atari ST). It provides an easy to handle (mouse driven) object editor to create 3D models of medium complexity (15,000 vertices) from sections or from scratch. The models may be displayed in various modes including stereo viewing and complex animation sequences.

  16. Computer-Graphics Emulation of Chemical Instrumentation: Absorption Spectrophotometers.

    ERIC Educational Resources Information Center

    Gilbert, D. D.; And Others

    1982-01-01

    Describes interactive, computer-graphics program emulating behavior of high resolution, ultraviolet-visible analog recording spectrophotometer. Graphics terminal behaves as recording absorption spectrophotometer. Objective of the emulation is study of optimization of the instrument to yield accurate absorption spectra, including…

  17. Computer-Graphics Emulation of Chemical Instrumentation: Absorption Spectrophotometers.

    ERIC Educational Resources Information Center

    Gilbert, D. D.; And Others

    1982-01-01

    Describes interactive, computer-graphics program emulating behavior of high resolution, ultraviolet-visible analog recording spectrophotometer. Graphics terminal behaves as recording absorption spectrophotometer. Objective of the emulation is study of optimization of the instrument to yield accurate absorption spectra, including…

  18. Learning with Interactive Computer Graphics in the Undergraduate Neuroscience Classroom

    ERIC Educational Resources Information Center

    Pani, John R.; Chariker, Julia H.; Naaz, Farah; Mattingly, William; Roberts, Joshua; Sephton, Sandra E.

    2014-01-01

    Instruction of neuroanatomy depends on graphical representation and extended self-study. As a consequence, computer-based learning environments that incorporate interactive graphics should facilitate instruction in this area. The present study evaluated such a system in the undergraduate neuroscience classroom. The system used the method of…

  19. Computer Graphics and Metaphorical Elaboration for Learning Science Concepts.

    ERIC Educational Resources Information Center

    ChanLin, Lih-Juan; Chan, Kung-Chi

    This study explores the instructional impact of using computer multimedia to integrate metaphorical verbal information into graphical representations of biotechnology concepts. The combination of text and graphics into a single metaphor makes concepts dual-coded, and therefore more comprehensible and memorable for the student. Visual stimuli help…

  20. Learning with Interactive Computer Graphics in the Undergraduate Neuroscience Classroom

    ERIC Educational Resources Information Center

    Pani, John R.; Chariker, Julia H.; Naaz, Farah; Mattingly, William; Roberts, Joshua; Sephton, Sandra E.

    2014-01-01

    Instruction of neuroanatomy depends on graphical representation and extended self-study. As a consequence, computer-based learning environments that incorporate interactive graphics should facilitate instruction in this area. The present study evaluated such a system in the undergraduate neuroscience classroom. The system used the method of…

  1. Three-dimensional human computer interaction based on 3D widgets for medical data visualization

    NASA Astrophysics Data System (ADS)

    Xue, Jian; Tian, Jie; Zhao, Mingchang

    2005-04-01

    Three-dimensional human computer interaction plays an important role in 3-dimensional visualization. It is important for clinicians to accurately use and easily handle the result of medical data visualization in order to assist diagnosis and surgery simulation. A 3D human computer interaction software platform based on 3D widgets has been designed in traditional object-oriented fashion with some common design patterns and implemented by using ANSI C++, including all function modules and some practical widgets. A group of application examples are exhibited as well. The ultimate objective is to provide a flexible, reliable and extensible 3-D interaction platform for medical image processing and analyzing.

  2. X-33 Landing - Computer generated graphic

    NASA Technical Reports Server (NTRS)

    1996-01-01

    This 46-second clip has the X-33 aircraft on final approach to Michael AAF in Utah, then with its landing gear down, it flares for touchdown and brakes to a halt. This graphic like the three before it shows an early configuration without vertical stabilizers, which have since been added.

  3. X-33 Landing - Computer generated graphic

    NASA Technical Reports Server (NTRS)

    1996-01-01

    This 46-second clip has the X-33 aircraft on final approach to Michael AAF in Utah, then with its landing gear down, it flares for touchdown and brakes to a halt. This graphic like the three before it shows an early configuration without vertical stabilizers, which have since been added.

  4. Electro-holography display using computer generated hologram of 3D objects based on projection spectra

    NASA Astrophysics Data System (ADS)

    Huang, Sujuan; Wang, Duocheng; He, Chao

    2012-11-01

    A new method of synthesizing computer-generated hologram of three-dimensional (3D) objects is proposed from their projection images. A series of projection images of 3D objects are recorded with one-dimensional azimuth scanning. According to the principles of paraboloid of revolution in 3D Fourier space and 3D central slice theorem, spectra information of 3D objects can be gathered from their projection images. Considering quantization error of horizontal and vertical directions, the spectrum information from each projection image is efficiently extracted in double circle and four circles shape, to enhance the utilization of projection spectra. Then spectra information of 3D objects from all projection images is encoded into computer-generated hologram based on Fourier transform using conjugate-symmetric extension. The hologram includes 3D information of objects. Experimental results for numerical reconstruction of the CGH at different distance validate the proposed methods and show its good performance. Electro-holographic reconstruction can be realized by using an electronic addressing reflective liquid-crystal display (LCD) spatial light modulator. The CGH from the computer is loaded onto the LCD. By illuminating a reference light from a laser source to the LCD, the amplitude and phase information included in the CGH will be reconstructed due to the diffraction of the light modulated by the LCD.

  5. Space-time software: Computer graphics utilities in special relativity

    NASA Astrophysics Data System (ADS)

    Taylor, Edwin F.

    1989-06-01

    No one can experience directly the world of the very fast, described by special relativity. Interactive graphics displays have been developed for personal computers that help students visualize this world. They are in the form of interactive graphics utilities that students use to carry out homework exercises and take-home projects. Sequential versions of these programs have been used for 3 years in classes in various institutions. This article describes the programs and reports on the educational outcomes of these computer uses.

  6. Computer graphics visions and challenges: a European perspective.

    PubMed

    Encarnação, José L

    2006-01-01

    I have briefly described important visions and challenges in computer graphics. They are a personal and therefore subjective selection. But most of these issues have to be addressed and solved--no matter if we call them visions or challenges or something else--if we want to make and further develop computer graphics into a key enabling technology for our IT-based society.

  7. Magnetic Resonance Materials in Physics, Biology and Medicine Fast Reduction of Undersampling Artifacts in Radial MR Angiography with 3D Total Variation on Graphics Hardware

    PubMed Central

    Knoll, Florian; Unger, Markus; Diwoky, Clemens; Clason, Christian; Pock, Thomas; Stollberger, Rudolf

    2014-01-01

    Objective Subsampling of radially encoded MRI acquisitions in combination with sparsity promoting methods opened a door to significantly increased imaging speed, which is crucial for many important clinical applications. In particular, it has been shown recently that total variation (TV) regularization efficiently reduces undersampling artifacts. The drawback of the method is the long reconstruction time which makes it impossible to use in daily clinical practice, especially if the TV optimization problem has to be solved repeatedly to select a proper regularization parameter. Materials and Methods The goal of this work was to show that for the case of MR-Angiography, TV filtering can be performed as a post-processing step, in contrast to the common approach of integrating TV penalties in the image reconstruction process. With this approach it is possible to use TV algorithms with data fidelity terms in image space, which can be implemented very efficiently on graphic processing units (GPUs). The combination of a special radial sampling trajectory and a full 3D formulation of the TV minimization problem is crucial for the effectiveness of the artifact elimination process. Results and Conclusion The computation times of GPU-TV show that interactive elimination of undersampling artifacts is possible even for large volume data sets, in particular allowing the interactive determination of the regularization parameter. Results from phantom measurements and in vivo angiography data sets show that 3D TV, together with the proposed sampling trajectory, leads to pronounced improvements in image quality. However, while artifact removal was very efficient for angiography data sets in this work, it cannot be expected that the proposed method of TV post-processing will work for arbitrary types of scans. PMID:20352289

  8. GRID2D/3D: A computer program for generating grid systems in complex-shaped two- and three-dimensional spatial domains. Part 1: Theory and method

    NASA Technical Reports Server (NTRS)

    Shih, T. I.-P.; Bailey, R. T.; Nguyen, H. L.; Roelke, R. J.

    1990-01-01

    An efficient computer program, called GRID2D/3D was developed to generate single and composite grid systems within geometrically complex two- and three-dimensional (2- and 3-D) spatial domains that can deform with time. GRID2D/3D generates single grid systems by using algebraic grid generation methods based on transfinite interpolation in which the distribution of grid points within the spatial domain is controlled by stretching functions. All single grid systems generated by GRID2D/3D can have grid lines that are continuous and differentiable everywhere up to the second-order. Also, grid lines can intersect boundaries of the spatial domain orthogonally. GRID2D/3D generates composite grid systems by patching together two or more single grid systems. The patching can be discontinuous or continuous. For continuous composite grid systems, the grid lines are continuous and differentiable everywhere up to the second-order except at interfaces where different single grid systems meet. At interfaces where different single grid systems meet, the grid lines are only differentiable up to the first-order. For 2-D spatial domains, the boundary curves are described by using either cubic or tension spline interpolation. For 3-D spatial domains, the boundary surfaces are described by using either linear Coon's interpolation, bi-hyperbolic spline interpolation, or a new technique referred to as 3-D bi-directional Hermite interpolation. Since grid systems generated by algebraic methods can have grid lines that overlap one another, GRID2D/3D contains a graphics package for evaluating the grid systems generated. With the graphics package, the user can generate grid systems in an interactive manner with the grid generation part of GRID2D/3D. GRID2D/3D is written in FORTRAN 77 and can be run on any IBM PC, XT, or AT compatible computer. In order to use GRID2D/3D on workstations or mainframe computers, some minor modifications must be made in the graphics part of the program; no

  9. Time- and Computation-Efficient Calibration of MEMS 3D Accelerometers and Gyroscopes

    PubMed Central

    Stančin, Sara; Tomažič, Sašo

    2014-01-01

    We propose calibration methods for microelectromechanical system (MEMS) 3D accelerometers and gyroscopes that are efficient in terms of time and computational complexity. The calibration process for both sensors is simple, does not require additional expensive equipment, and can be performed in the field before or between motion measurements. The methods rely on a small number of defined calibration measurements that are used to obtain the values of 12 calibration parameters. This process enables the static compensation of sensor inaccuracies. The values detected by the 3D sensor are interpreted using a generalized 3D sensor model. The model assumes that the values detected by the sensor are equal to the projections of the measured value on the sensor sensitivity axes. Although this finding is trivial for 3D accelerometers, its validity for 3D gyroscopes is not immediately apparent; thus, this paper elaborates on this latter topic. For an example sensor device, calibration parameters were established using calibration measurements of approximately 1.5 min in duration for the 3D accelerometer and 2.5 min in duration for the 3D gyroscope. Correction of each detected 3D value using the established calibration parameters in further measurements requires only nine addition and nine multiplication operations. PMID:25123469

  10. Time- and computation-efficient calibration of MEMS 3D accelerometers and gyroscopes.

    PubMed

    Stančin, Sara; Tomažič, Sašo

    2014-08-13

    We propose calibration methods for microelectromechanical system (MEMS) 3D accelerometers and gyroscopes that are efficient in terms of time and computational complexity. The calibration process for both sensors is simple, does not require additional expensive equipment, and can be performed in the field before or between motion measurements. The methods rely on a small number of defined calibration measurements that are used to obtain the values of 12 calibration parameters. This process enables the static compensation of sensor inaccuracies. The values detected by the 3D sensor are interpreted using a generalized 3D sensor model. The model assumes that the values detected by the sensor are equal to the projections of the measured value on the sensor sensitivity axes. Although this finding is trivial for 3D accelerometers, its validity for 3D gyroscopes is not immediately apparent; thus, this paper elaborates on this latter topic. For an example sensor device, calibration parameters were established using calibration measurements of approximately 1.5 min in duration for the 3D accelerometer and 2.5 min in duration for the 3D gyroscope. Correction of each detected 3D value using the established calibration parameters in further measurements requires only nine addition and nine multiplication operations.

  11. Extended gray level co-occurrence matrix computation for 3D image volume

    NASA Astrophysics Data System (ADS)

    Salih, Nurulazirah M.; Dewi, Dyah Ekashanti Octorina

    2017-02-01

    Gray Level Co-occurrence Matrix (GLCM) is one of the main techniques for texture analysis that has been widely used in many applications. Conventional GLCMs usually focus on two-dimensional (2D) image texture analysis only. However, a three-dimensional (3D) image volume requires specific texture analysis computation. In this paper, an extended 2D to 3D GLCM approach based on the concept of multiple 2D plane positions and pixel orientation directions in the 3D environment is proposed. The algorithm was implemented by breaking down the 3D image volume into 2D slices based on five different plane positions (coordinate axes and oblique axes) resulting in 13 independent directions, then calculating the GLCMs. The resulted GLCMs were averaged to obtain normalized values, then the 3D texture features were calculated. A preliminary examination was performed on a 3D image volume (64 x 64 x 64 voxels). Our analysis confirmed that the proposed technique is capable of extracting the 3D texture features from the extended GLCMs approach. It is a simple and comprehensive technique that can contribute to the 3D image analysis.

  12. Some computer graphical user interfaces in radiation therapy

    PubMed Central

    Chow, James C L

    2016-01-01

    In this review, five graphical user interfaces (GUIs) used in radiation therapy practices and researches are introduced. They are: (1) the treatment time calculator, superficial X-ray treatment time calculator (SUPCALC) used in the superficial X-ray radiation therapy; (2) the monitor unit calculator, electron monitor unit calculator (EMUC) used in the electron radiation therapy; (3) the multileaf collimator machine file creator, sliding window intensity modulated radiotherapy (SWIMRT) used in generating fluence map for research and quality assurance in intensity modulated radiation therapy; (4) the treatment planning system, DOSCTP used in the calculation of 3D dose distribution using Monte Carlo simulation; and (5) the monitor unit calculator, photon beam monitor unit calculator (PMUC) used in photon beam radiation therapy. One common issue of these GUIs is that all user-friendly interfaces are linked to complex formulas and algorithms based on various theories, which do not have to be understood and noted by the user. In that case, user only needs to input the required information with help from graphical elements in order to produce desired results. SUPCALC is a superficial radiation treatment time calculator using the GUI technique to provide a convenient way for radiation therapist to calculate the treatment time, and keep a record for the skin cancer patient. EMUC is an electron monitor unit calculator for electron radiation therapy. Instead of doing hand calculation according to pre-determined dosimetric tables, clinical user needs only to input the required drawing of electron field in computer graphical file format, prescription dose, and beam parameters to EMUC to calculate the required monitor unit for the electron beam treatment. EMUC is based on a semi-experimental theory of sector-integration algorithm. SWIMRT is a multileaf collimator machine file creator to generate a fluence map produced by a medical linear accelerator. This machine file controls

  13. Some computer graphical user interfaces in radiation therapy.

    PubMed

    Chow, James C L

    2016-03-28

    In this review, five graphical user interfaces (GUIs) used in radiation therapy practices and researches are introduced. They are: (1) the treatment time calculator, superficial X-ray treatment time calculator (SUPCALC) used in the superficial X-ray radiation therapy; (2) the monitor unit calculator, electron monitor unit calculator (EMUC) used in the electron radiation therapy; (3) the multileaf collimator machine file creator, sliding window intensity modulated radiotherapy (SWIMRT) used in generating fluence map for research and quality assurance in intensity modulated radiation therapy; (4) the treatment planning system, DOSCTP used in the calculation of 3D dose distribution using Monte Carlo simulation; and (5) the monitor unit calculator, photon beam monitor unit calculator (PMUC) used in photon beam radiation therapy. One common issue of these GUIs is that all user-friendly interfaces are linked to complex formulas and algorithms based on various theories, which do not have to be understood and noted by the user. In that case, user only needs to input the required information with help from graphical elements in order to produce desired results. SUPCALC is a superficial radiation treatment time calculator using the GUI technique to provide a convenient way for radiation therapist to calculate the treatment time, and keep a record for the skin cancer patient. EMUC is an electron monitor unit calculator for electron radiation therapy. Instead of doing hand calculation according to pre-determined dosimetric tables, clinical user needs only to input the required drawing of electron field in computer graphical file format, prescription dose, and beam parameters to EMUC to calculate the required monitor unit for the electron beam treatment. EMUC is based on a semi-experimental theory of sector-integration algorithm. SWIMRT is a multileaf collimator machine file creator to generate a fluence map produced by a medical linear accelerator. This machine file controls

  14. Computing 3-D structure of rigid objects using stereo and motion

    NASA Technical Reports Server (NTRS)

    Nguyen, Thinh V.

    1987-01-01

    Work performed as a step toward an intelligent automatic machine vision system for 3-D imaging is discussed. The problem considered is the quantitative 3-D reconstruction of rigid objects. Motion and stereo are the two clues considered in this system. The system basically consists of three processes: the low level process to extract image features, the middle level process to establish the correspondence in the stereo (spatial) and motion (temporal) modalities, and the high level process to compute the 3-D coordinates of the corner points by integrating the spatial and temporal correspondences.

  15. Computational efficient segmentation of cell nuclei in 2D and 3D fluorescent micrographs

    NASA Astrophysics Data System (ADS)

    De Vylder, Jonas; Philips, Wilfried

    2011-02-01

    This paper proposes a new segmentation technique developed for the segmentation of cell nuclei in both 2D and 3D fluorescent micrographs. The proposed method can deal with both blurred edges as with touching nuclei. Using a dual scan line algorithm its both memory as computational efficient, making it interesting for the analysis of images coming from high throughput systems or the analysis of 3D microscopic images. Experiments show good results, i.e. recall of over 0.98.

  16. Degenerative changes of the vertebral column in spatial imaging of 3D computed tomography.

    PubMed

    Krupski, Witold; Majcher, Piotr; Krupski, Mirosław; Fatyga, Marek; Złomaniec, Janusz

    2002-01-01

    In a group of 38 patients with radicular pain syndromes diagnostic value of spatial reconstructions with computed tomography (3D CT) was assessed in examinations of bone structures of the vertebral column. It was found that 3D CT is a technique of choice in the assessment of degenerative stenosis of the vertebral canal, internal surface of the vertebral canal, bone narrowings of intervertebral foramens and lateral recesses.

  17. 3-D field computation: The near-triumph of commerical codes

    SciTech Connect

    Turner, L.R.

    1995-07-01

    In recent years, more and more of those who design and analyze magnets and other devices are using commercial codes rather than developing their own. This paper considers the commercial codes and the features available with them. Other recent trends with 3-D field computation include parallel computation and visualization methods such as virtual reality systems.

  18. A new 3D computational model for shaped charge jet breakup

    SciTech Connect

    Zernow, L.; Chapyak, E.J.; Mosso, S.J.

    1996-09-01

    This paper reviews prior 1D and 2D axisymmetric, analytical and computational studies, as well as empirical studies of the shaped charge jet particulation problem and discusses their associated insights and problems. It proposes a new 3D computational model of the particulation process, based upon a simplified version of the observed counter-rotating, double helical surface perturbations, found on softly recovered shaped charge jet particles, from both copper and tantalum jets. This 3D approach contrasts with the random, axisymmetric surface perturbations which have previously been used, to try to infer the observed length distribution of jet particles, on the basis of the most unstable wavelength concept, which leads to the expectation of a continuous distribution of particle lengths. The 3D model, by its very nature, leads to a non-random, periodic distribution of potential initial necking loci, on alternate sides of the stretching jet. This in turn infers a potentially periodic, overlapping, multi-modal distribution of associated jet particle lengths. Since it is unlikely that all potential initial necking sites will be activated simultaneously, the 3D model also suggests that longer jet particles containing partial, but unseparated necks, should be observed fairly often. The computational analysis is in its very early stages and the problems involved in inserting the two helical grooves and in defining the initial conditions and boundary conditions for the computation will be discussed. Available initial results from the 3D computation will be discussed and interpreted.

  19. Computing elastic moduli on 3-D X-ray computed tomography image stacks

    NASA Astrophysics Data System (ADS)

    Garboczi, E. J.; Kushch, V. I.

    2015-03-01

    A numerical task of current interest is to compute the effective elastic properties of a random composite material by operating on a 3D digital image of its microstructure obtained via X-ray computed tomography (CT). The 3-D image is usually sub-sampled since an X-ray CT image is typically of order 10003 voxels or larger, which is considered to be a very large finite element problem. Two main questions for the validity of any such study are then: can the sub-sample size be made sufficiently large to capture enough of the important details of the random microstructure so that the computed moduli can be thought of as accurate, and what boundary conditions should be chosen for these sub-samples? This paper contributes to the answer of both questions by studying a simulated X-ray CT cylindrical microstructure with three phases, cut from a random model system with known elastic properties. A new hybrid numerical method is introduced, which makes use of finite element solutions coupled with exact solutions for elastic moduli of square arrays of parallel cylindrical fibers. The new method allows, in principle, all of the microstructural data to be used when the X-ray CT image is in the form of a cylinder, which is often the case. Appendix A describes a similar algorithm for spherical sub-samples, which may be of use when examining the mechanical properties of particles. Cubic sub-samples are also taken from this simulated X-ray CT structure to investigate the effect of two different kinds of boundary conditions: forced periodic and fixed displacements. It is found that using forced periodic displacements on the non-geometrically periodic cubic sub-samples always gave more accurate results than using fixed displacements, although with about the same precision. The larger the cubic sub-sample, the more accurate and precise was the elastic computation, and using the complete cylindrical sample with the new method gave still more accurate and precise results. Fortran 90

  20. 3D Slicer as an Image Computing Platform for the Quantitative Imaging Network

    PubMed Central

    Fedorov, Andriy; Beichel, Reinhard; Kalpathy-Cramer, Jayashree; Finet, Julien; Fillion-Robin, Jean-Christophe; Pujol, Sonia; Bauer, Christian; Jennings, Dominique; Fennessy, Fiona; Sonka, Milan; Buatti, John; Aylward, Stephen; Miller, James V.; Pieper, Steve; Kikinis, Ron

    2012-01-01

    Quantitative analysis has tremendous but mostly unrealized potential in healthcare to support objective and accurate interpretation of the clinical imaging. In 2008, the National Cancer Institute began building the Quantitative Imaging Network (QIN) initiative with the goal of advancing quantitative imaging in the context of personalized therapy and evaluation of treatment response. Computerized analysis is an important component contributing to reproducibility and efficiency of the quantitative imaging techniques. The success of quantitative imaging is contingent on robust analysis methods and software tools to bring these methods from bench to bedside. 3D Slicer is a free open source software application for medical image computing. As a clinical research tool, 3D Slicer is similar to a radiology workstation that supports versatile visualizations but also provides advanced functionality such as automated segmentation and registration for a variety of application domains. Unlike a typical radiology workstation, 3D Slicer is free and is not tied to specific hardware. As a programming platform, 3D Slicer facilitates translation and evaluation of the new quantitative methods by allowing the biomedical researcher to focus on the implementation of the algorithm, and providing abstractions for the common tasks of data communication, visualization and user interface development. Compared to other tools that provide aspects of this functionality, 3D Slicer is fully open source and can be readily extended and redistributed. In addition, 3D Slicer is designed to facilitate the development of new functionality in the form of 3D Slicer extensions. In this paper, we present an overview of 3D Slicer as a platform for prototyping, development and evaluation of image analysis tools for clinical research applications. To illustrate the utility of the platform in the scope of QIN, we discuss several use cases of 3D Slicer by the existing QIN teams, and we elaborate on the future

  1. Implementation of Headtracking and 3D Stereo with Unity and VRPN for Computer Simulations

    NASA Technical Reports Server (NTRS)

    Noyes, Matthew A.

    2013-01-01

    This paper explores low-cost hardware and software methods to provide depth cues traditionally absent in monocular displays. The use of a VRPN server in conjunction with a Microsoft Kinect and/or Nintendo Wiimote to provide head tracking information to a Unity application, and NVIDIA 3D Vision for retinal disparity support, is discussed. Methods are suggested to implement this technology with NASA's EDGE simulation graphics package, along with potential caveats. Finally, future applications of this technology to astronaut crew training, particularly when combined with an omnidirectional treadmill for virtual locomotion and NASA's ARGOS system for reduced gravity simulation, are discussed.

  2. Computer-Graphical Simulation Of Robotic Welding

    NASA Technical Reports Server (NTRS)

    Fernandez, Ken; Cook, George

    1988-01-01

    Computer program ROBOSIM, developed to simulate operations of robots, applied to preliminary design of robotic arc-welding operation. Limitations on equipment investigated in advance to prevent expensive mistakes. Computer makes drawing of robotic welder and workpiece on positioning table. Such numerical simulation used to perform rapid, safe experiments in computer-aided design or manufacturing.

  3. Graphics and flow visualization in computational fluid dynamics

    NASA Technical Reports Server (NTRS)

    Buning, P. G.; Steger, J. L.

    1985-01-01

    Techniques for displaying two- and three-dimensional flowfield solutions are described. Several methods of illustrating flow structure are addressed including particle tracing, simulated oil flow, and shock finding. These are incorporated into an interactive graphics program for CFD flowfields, called PLOT3D. Emphasis is made on the difficulty in visualizing three-dimensional flow features, and the importance of color, fast 3D image manipulation, and dynamic movie play-back in displaying such flows. The need for advanced algorithms to identify shock waves, vortices, and separation lines is pointed out. It is likely that the supercomputer will be needed for this process because of the size of 3D and/or unsteady CFD databases.

  4. 3D Multislice and Cone-beam Computed Tomography Systems for Dental Identification.

    PubMed

    Eliášová, Hana; Dostálová, Taťjana

    3D Multislice and Cone-beam computed tomography (CBCT) in forensic odontology has been shown to be useful not only in terms of one or a few of dead bodies but also in multiple fatality incidents. 3D Multislice and Cone-beam computed tomography and digital radiography were demonstrated in a forensic examination form. 3D images of the skull and teeth were analysed and validated for long ante mortem/post mortem intervals. The image acquisition was instantaneous; the images were able to be optically enlarged, measured, superimposed and compared prima vista or using special software and exported as a file. Digital radiology and computer tomography has been shown to be important both in common criminalistics practices and in multiple fatality incidents. Our study demonstrated that CBCT imaging offers less image artifacts, low image reconstruction times, mobility of the unit and considerably lower equipment cost.

  5. Retrospective Study on Mathematical Modeling Based on Computer Graphic Processing

    NASA Astrophysics Data System (ADS)

    Zhang, Kai Li

    Graphics & image making is an important field in computer application, in which visualization software has been widely used with the characteristics of convenience and quick. However, it was thought by modeling designers that the software had been limited in it's function and flexibility because mathematics modeling platform was not built. A non-visualization graphics software appearing at this moment enabled the graphics & image design has a very good mathematics modeling platform. In the paper, a polished pyramid is established by multivariate spline function algorithm, and validate the non-visualization software is good in mathematical modeling.

  6. Integration of rocket turbine design and analysis through computer graphics

    NASA Technical Reports Server (NTRS)

    Hsu, Wayne; Boynton, Jim

    1988-01-01

    An interactive approach with engineering computer graphics is used to integrate the design and analysis processes of a rocket engine turbine into a progressive and iterative design procedure. The processes are interconnected through pre- and postprocessors. The graphics are used to generate the blade profiles, their stacking, finite element generation, and analysis presentation through color graphics. Steps of the design process discussed include pitch-line design, axisymmetric hub-to-tip meridional design, and quasi-three-dimensional analysis. The viscous two- and three-dimensional analysis codes are executed after acceptable designs are achieved and estimates of initial losses are confirmed.

  7. Integration of rocket turbine design and analysis through computer graphics

    NASA Technical Reports Server (NTRS)

    Hsu, Wayne; Boynton, Jim

    1988-01-01

    An interactive approach with engineering computer graphics is used to integrate the design and analysis processes of a rocket engine turbine into a progressive and iterative design procedure. The processes are interconnected through pre- and postprocessors. The graphics are used to generate the blade profiles, their stacking, finite element generation, and analysis presentation through color graphics. Steps of the design process discussed include pitch-line design, axisymmetric hub-to-tip meridional design, and quasi-three-dimensional analysis. The viscous two- and three-dimensional analysis codes are executed after acceptable designs are achieved and estimates of initial losses are confirmed.

  8. Iconographic dental typography. A dental character font for computer graphics.

    PubMed

    McCormack, J

    1991-06-08

    The recent massive increase in available memory for microcomputers now allows multiple font faces to be stored in computer RAM memory for instant access to the screen and for printed output. Fonts can be constructed in which the characters are not just letters or numbers, but are miniature graphic icons--in this instance pictures of teeth. When printed on an appropriate laser printer, this produces printed graphics of publishing quality.

  9. Meta!Blast computer game: a pipeline from science to 3D art to education

    NASA Astrophysics Data System (ADS)

    Schneller, William; Campbell, P. J.; Bassham, Diane; Wurtele, Eve Syrkin

    2012-03-01

    Meta!Blast (http://www.metablast.org) is designed to address the challenges students often encounter in understanding cell and metabolic biology. Developed by faculty and students in biology, biochemistry, computer science, game design, pedagogy, art and story, Meta!Blast is being created using Maya (http://usa.autodesk.com/maya/) and the Unity 3D (http://unity3d.com/) game engine, for Macs and PCs in classrooms; it has also been exhibited in an immersive environment. Here, we describe the pipeline from protein structural data and holographic information to art to the threedimensional (3D) environment to the game engine, by which we provide a publicly-available interactive 3D cellular world that mimics a photosynthetic plant cell.

  10. Integrating user studies into computer graphics-related courses.

    PubMed

    Santos, B S; Dias, P; Silva, S; Ferreira, C; Madeira, J

    2011-01-01

    This paper presents computer graphics. Computer graphics and visualization are essentially about producing images for a target audience, be it the millions watching a new CG-animated movie or the small group of researchers trying to gain insight into the large amount of numerical data resulting from a scientific experiment. To ascertain the final images' effectiveness for their intended audience or the designed visualizations' accuracy and expressiveness, formal user studies are often essential. In human-computer interaction (HCI), such user studies play a similar fundamental role in evaluating the usability and applicability of interaction methods and metaphors for the various devices and software systems we use.

  11. Computer graphic method for direct correspondence image acquisition used in full parallax holographic stereograms

    NASA Astrophysics Data System (ADS)

    Madrid Sánchez, Alejandro; Velásquez Prieto, Daniel

    2016-09-01

    The holoprinter technology based on holographic stereograms has generated a fast development in holographic display applications by the holographic recording of a 2D image sequence with information of a 3D scene, which could be real or computer generated. The images used in holographic stereograms initially start from the acquisition of the different image perspectives of the 3D scene by the re-centering camera configuration and then, this images must be rearranged before the optical recording. This paper proposes a method to acquire the required images or hogel images in one step without using rearrange algorithms, the method uses a virtual camera that moves along a virtual rail by conventional computer graphics software. The proposed method reduced the time required to obtain the hogel images and enhance the quality of the 3D holographic images; it also can be applied in different computer graphics software. To validate the method, a full parallax holographic stereogram was made for a computer generated object.

  12. Computation and graphics in mathematical research

    SciTech Connect

    Hoffman, D.A.; Spruck, J.

    1993-06-01

    Current research is described on: grain boundaries and dislocations in compound polymers, boundary value problems for hypersurfaces constant Gaussian curvature, and discrete computational geometry. 19 refs, 4 figs.

  13. Computer Art--A New Tool in Advertising Graphics.

    ERIC Educational Resources Information Center

    Wassmuth, Birgit L.

    Using computers to produce art began with scientists, mathematicians, and individuals with strong technical backgrounds who used the graphic material as visualizations of data in technical fields. People are using computer art in advertising, as well as in painting; sculpture; music; textile, product, industrial, and interior design; architecture;…

  14. Computer Art--A New Tool in Advertising Graphics.

    ERIC Educational Resources Information Center

    Wassmuth, Birgit L.

    Using computers to produce art began with scientists, mathematicians, and individuals with strong technical backgrounds who used the graphic material as visualizations of data in technical fields. People are using computer art in advertising, as well as in painting; sculpture; music; textile, product, industrial, and interior design; architecture;…

  15. The Use of Computer Graphics in the Design Process.

    ERIC Educational Resources Information Center

    Palazzi, Maria

    This master's thesis examines applications of computer technology to the field of industrial design and ways in which technology can transform the traditional process. Following a statement of the problem, the history and applications of the fields of computer graphics and industrial design are reviewed. The traditional industrial design process…

  16. Graphics and composite material computer program enhancements for SPAR

    NASA Technical Reports Server (NTRS)

    Farley, G. L.; Baker, D. J.

    1980-01-01

    User documentation is provided for additional computer programs developed for use in conjunction with SPAR. These programs plot digital data, simplify input for composite material section properties, and compute lamina stresses and strains. Sample problems are presented including execution procedures, program input, and graphical output.

  17. Computational methods for constructing protein structure models from 3D electron microscopy maps.

    PubMed

    Esquivel-Rodríguez, Juan; Kihara, Daisuke

    2013-10-01

    Protein structure determination by cryo-electron microscopy (EM) has made significant progress in the past decades. Resolutions of EM maps have been improving as evidenced by recently reported structures that are solved at high resolutions close to 3Å. Computational methods play a key role in interpreting EM data. Among many computational procedures applied to an EM map to obtain protein structure information, in this article we focus on reviewing computational methods that model protein three-dimensional (3D) structures from a 3D EM density map that is constructed from two-dimensional (2D) maps. The computational methods we discuss range from de novo methods, which identify structural elements in an EM map, to structure fitting methods, where known high resolution structures are fit into a low-resolution EM map. A list of available computational tools is also provided.

  18. Using Computer Graphics in the 90's.

    ERIC Educational Resources Information Center

    Towne, Violet A.

    Computer-Aided Design, a hands-on program for public school teachers, was first offered in the summer of 1987 as an outgrowth of a 1986 robotics training program. Area technology teachers needed computer-aided design (CAD) training because of a New York State Education system transition from the industrial arts curriculum to a new curriculum in…

  19. Graphical method for analyzing digital computer efficiency

    NASA Technical Reports Server (NTRS)

    Chan, S. P.; Munoz, R. M.

    1971-01-01

    Analysis method utilizes graph-theoretic approach for evaluating computation cost and makes logical distinction between linear graph of a computation and linear graph of a program. It applies equally well to other processes which depend on quatitative edge nomenclature and precedence relationships between edges.

  20. Computer Graphics for System Effectiveness Analysis.

    DTIC Science & Technology

    1986-05-01

    using the round operation when computing the number of shots: a real number must be converted into an integer number [ Chapra and ... Canale, 1985]. Then...02139, August 1982. Chapra , Steven C., and Raymond P. Canale, (1985), Numerical Methods for Engineers with Personal Computer Applications New York

  1. 3D computation of non-linear eddy currents: Variational method and superconducting cubic bulk

    NASA Astrophysics Data System (ADS)

    Pardo, Enric; Kapolka, Milan

    2017-09-01

    Computing the electric eddy currents in non-linear materials, such as superconductors, is not straightforward. The design of superconducting magnets and power applications needs electromagnetic computer modeling, being in many cases a three-dimensional (3D) problem. Since 3D problems require high computing times, novel time-efficient modeling tools are highly desirable. This article presents a novel computing modeling method based on a variational principle. The self-programmed implementation uses an original minimization method, which divides the sample into sectors. This speeds-up the computations with no loss of accuracy, while enabling efficient parallelization. This method could also be applied to model transients in linear materials or networks of non-linear electrical elements. As example, we analyze the magnetization currents of a cubic superconductor. This 3D situation remains unknown, in spite of the fact that it is often met in material characterization and bulk applications. We found that below the penetration field and in part of the sample, current flux lines are not rectangular and significantly bend in the direction parallel to the applied field. In conclusion, the presented numerical method is able to time-efficiently solve fully 3D situations without loss of accuracy.

  2. Efficient curve-skeleton computation for the analysis of biomedical 3d images - biomed 2010.

    PubMed

    Brun, Francesco; Dreossi, Diego

    2010-01-01

    Advances in three dimensional (3D) biomedical imaging techniques, such as magnetic resonance (MR) and computed tomography (CT), make it easy to reconstruct high quality 3D models of portions of human body and other biological specimens. A major challenge lies in the quantitative analysis of the resulting models thus allowing a more comprehensive characterization of the object under investigation. An interesting approach is based on curve-skeleton (or medial axis) extraction, which gives basic information concerning the topology and the geometry. Curve-skeletons have been applied in the analysis of vascular networks and the diagnosis of tracheal stenoses as well as a 3D flight path in virtual endoscopy. However curve-skeleton computation is a crucial task. An effective skeletonization algorithm was introduced by N. Cornea in [1] but it lacks in computational performances. Thanks to the advances in imaging techniques the resolution of 3D images is increasing more and more, therefore there is the need for efficient algorithms in order to analyze significant Volumes of Interest (VOIs). In the present paper an improved skeletonization algorithm based on the idea proposed in [1] is presented. A computational comparison between the original and the proposed method is also reported. The obtained results show that the proposed method allows a significant computational improvement making more appealing the adoption of the skeleton representation in biomedical image analysis applications.

  3. Introduction of the ASP3D Computer Program for Unsteady Aerodynamic and Aeroelastic Analyses

    NASA Technical Reports Server (NTRS)

    Batina, John T.

    2005-01-01

    A new computer program has been developed called ASP3D (Advanced Small Perturbation 3D), which solves the small perturbation potential flow equation in an advanced form including mass-consistent surface and trailing wake boundary conditions, and entropy, vorticity, and viscous effects. The purpose of the program is for unsteady aerodynamic and aeroelastic analyses, especially in the nonlinear transonic flight regime. The program exploits the simplicity of stationary Cartesian meshes with the movement or deformation of the configuration under consideration incorporated into the solution algorithm through a planar surface boundary condition. The new ASP3D code is the result of a decade of developmental work on improvements to the small perturbation formulation, performed while the author was employed as a Senior Research Scientist in the Configuration Aerodynamics Branch at the NASA Langley Research Center. The ASP3D code is a significant improvement to the state-of-the-art for transonic aeroelastic analyses over the CAP-TSD code (Computational Aeroelasticity Program Transonic Small Disturbance), which was developed principally by the author in the mid-1980s. The author is in a unique position as the developer of both computer programs to compare, contrast, and ultimately make conclusions regarding the underlying formulations and utility of each code. The paper describes the salient features of the ASP3D code including the rationale for improvements in comparison with CAP-TSD. Numerous results are presented to demonstrate the ASP3D capability. The general conclusion is that the new ASP3D capability is superior to the older CAP-TSD code because of the myriad improvements developed and incorporated.

  4. Computer-Assisted Hepatocellular Carcinoma Ablation Planning Based on 3-D Ultrasound Imaging.

    PubMed

    Li, Kai; Su, Zhongzhen; Xu, Erjiao; Guan, Peishan; Li, Liu-Jun; Zheng, Rongqin

    2016-08-01

    To evaluate computer-assisted hepatocellular carcinoma (HCC) ablation planning based on 3-D ultrasound, 3-D ultrasound images of 60 HCC lesions from 58 patients were obtained and transferred to a research toolkit. Compared with virtual manual ablation planning (MAP), virtual computer-assisted ablation planning (CAP) consumed less time and needle insertion numbers and exhibited a higher rate of complete tumor coverage and lower rate of critical structure injury. In MAP, junior operators used less time, but had more critical structure injury than senior operators. For large lesions, CAP performed better than MAP. For lesions near critical structures, CAP resulted in better outcomes than MAP. Compared with MAP, CAP based on 3-D ultrasound imaging was more effective and achieved a higher rate of complete tumor coverage and a lower rate of critical structure injury; it is especially useful for junior operators and with large lesions, and lesions near critical structures.

  5. Computer Graphics: More Help for Chemists

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1976

    1976-01-01

    Describes computer programs and projects designed to assist the chemical researcher in solving problems on-line. Discusses programs that interpret molecular structures, analyze multivariant data, and generate structural isomers of compounds. (MLH)

  6. Computer Graphics: More Help for Chemists

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1976

    1976-01-01

    Describes computer programs and projects designed to assist the chemical researcher in solving problems on-line. Discusses programs that interpret molecular structures, analyze multivariant data, and generate structural isomers of compounds. (MLH)

  7. Computer-assisted 3D planned corrective osteotomies in eight malunited radius fractures.

    PubMed

    Walenkamp, M M J; de Muinck Keizer, R J O; Dobbe, J G G; Streekstra, G J; Goslings, J C; Kloen, P; Strackee, S D; Schep, N W L

    2015-08-01

    In corrective osteotomy of the radius, detailed preoperative planning is essential to optimising functional outcome. However, complex malunions are not completely addressed with conventional preoperative planning. Computer-assisted preoperative planning may optimise the results of corrective osteotomy of the radius. We analysed the pre- and postoperative radiological result of computer-assisted 3D planned corrective osteotomy in a series of patients with a malunited radius and assessed postoperative function. We included eight patients aged 13-64 who underwent a computer-assisted 3D planned corrective osteotomy of the radius for the treatment of a symptomatic radius malunion. We evaluated pre- and postoperative residual malpositioning on 3D reconstructions as expressed in six positioning parameters (three displacements along and three rotations about the axes of a 3D anatomical coordinate system) and assessed postoperative wrist range of motion. In this small case series, dorsopalmar tilt was significantly improved (p = 0.05). Ulnoradial shift, however, increased by the correction osteotomy (6 of 8 cases, 75 %). Postoperative 3D evaluation revealed improved positioning parameters for patients in axial rotational alignment (62.5 %), radial inclination (75 %), proximodistal shift (83 %) and volodorsal shift (88 %), although the cohort was not large enough to confirm this by statistical significance. All but one patient experienced improved range of motion (88 %). Computer-assisted 3D planning ameliorates alignment of radial malunions and improves functional results in patients with a symptomatic malunion of the radius. Further development is required to improve transfer of the planned position to the intra-operative bone. Level of evidence IV.

  8. The Effects of 3D Computer Simulation on Biology Students' Achievement and Memory Retention

    ERIC Educational Resources Information Center

    Elangovan, Tavasuria; Ismail, Zurida

    2014-01-01

    A quasi experimental study was conducted for six weeks to determine the effectiveness of two different 3D computer simulation based teaching methods, that is, realistic simulation and non-realistic simulation on Form Four Biology students' achievement and memory retention in Perak, Malaysia. A sample of 136 Form Four Biology students in Perak,…

  9. Analysis of thoracic aorta hemodynamics using 3D particle tracking velocimetry and computational fluid dynamics.

    PubMed

    Gallo, Diego; Gülan, Utku; Di Stefano, Antonietta; Ponzini, Raffaele; Lüthi, Beat; Holzner, Markus; Morbiducci, Umberto

    2014-09-22

    Parallel to the massive use of image-based computational hemodynamics to study the complex flow establishing in the human aorta, the need for suitable experimental techniques and ad hoc cases for the validation and benchmarking of numerical codes has grown more and more. Here we present a study where the 3D pulsatile flow in an anatomically realistic phantom of human ascending aorta is investigated both experimentally and computationally. The experimental study uses 3D particle tracking velocimetry (PTV) to characterize the flow field in vitro, while finite volume method is applied to numerically solve the governing equations of motion in the same domain, under the same conditions. Our findings show that there is an excellent agreement between computational and measured flow fields during the forward flow phase, while the agreement is poorer during the reverse flow phase. In conclusion, here we demonstrate that 3D PTV is very suitable for a detailed study of complex unsteady flows as in aorta and for validating computational models of aortic hemodynamics. In a future step, it will be possible to take advantage from the ability of 3D PTV to evaluate velocity fluctuations and, for this reason, to gain further knowledge on the process of transition to turbulence occurring in the thoracic aorta.

  10. Adaptive 3D single-block grids for the computation of viscous flows around wings

    SciTech Connect

    Hagmeijer, R.; Kok, J.C.

    1996-12-31

    A robust algorithm for the adaption of a 3D single-block structured grid suitable for the computation of viscous flows around a wing is presented and demonstrated by application to the ONERA M6 wing. The effects of grid adaption on the flow solution and accuracy improvements is analyzed. Reynolds number variations are studied.

  11. The Effects of 3D Computer Simulation on Biology Students' Achievement and Memory Retention

    ERIC Educational Resources Information Center

    Elangovan, Tavasuria; Ismail, Zurida

    2014-01-01

    A quasi experimental study was conducted for six weeks to determine the effectiveness of two different 3D computer simulation based teaching methods, that is, realistic simulation and non-realistic simulation on Form Four Biology students' achievement and memory retention in Perak, Malaysia. A sample of 136 Form Four Biology students in Perak,…

  12. Analyzing 3D xylem networks in Vitis vinifera using High Resolution Computed Tomography (HRCT)

    USDA-ARS?s Scientific Manuscript database

    Recent developments in High Resolution Computed Tomography (HRCT) have made it possible to visualize three dimensional (3D) xylem networks without time consuming, labor intensive physical sectioning. Here we describe a new method to visualize complex vessel networks in plants and produce a quantitat...

  13. Enhancement of temporal bone anatomy learning with computer 3D rendered imaging software.

    PubMed

    Venail, Frederic; Deveze, Arnaud; Lallemant, Benjamin; Guevara, Nicolas; Mondain, Michel

    2010-01-01

    To determine whether the use of 3D anatomical models is helpful to students and enhances their anatomical knowledge. First year undergraduate students on the speech therapy or hearing aid practitioner courses attended either a lecture alone or a lecture followed by a 3D anatomy based tutorial, the latter which was also attended by ENT residents. Participants who received the tutorial were free to use the 3D model on the university computers or on their home computer and were then asked to answer a satisfaction questionnaire. At the end of the first year examinations, the grades of the undergraduate students were compared between the lecture alone group and lecture plus tutorial group. Generally, all participants found this new tool interesting and user-friendly for the learning of temporal bone anatomy. However, most also considered the help of a teacher indispensable to guide them through the virtual dissection. First year undergraduate students who received the 3D anatomy tutorial performed significantly better during their end of year examination compared to those receiving a lecture alone, particularly concerning the more difficult questions. The 3D anatomical software, used in parallel with traditional teaching methods, such as lectures and cadaver dissection, appears to be a promising tool to improve student learning of temporal bone anatomy.

  14. 3D Computational Modeling of Proteins Using Sparse Paramagnetic NMR Data.

    PubMed

    Pilla, Kala Bharath; Otting, Gottfried; Huber, Thomas

    2017-01-01

    Computational modeling of proteins using evolutionary or de novo approaches offers rapid structural characterization, but often suffers from low success rates in generating high quality models comparable to the accuracy of structures observed in X-ray crystallography or nuclear magnetic resonance (NMR) spectroscopy. A computational/experimental hybrid approach incorporating sparse experimental restraints in computational modeling algorithms drastically improves reliability and accuracy of 3D models. This chapter discusses the use of structural information obtained from various paramagnetic NMR measurements and demonstrates computational algorithms implementing pseudocontact shifts as restraints to determine the structure of proteins at atomic resolution.

  15. X-33 Launch - Computer generated graphic

    NASA Technical Reports Server (NTRS)

    1996-01-01

    This 45-second computer-generated launch sequence begins with a view of the X-33 launch facility located near Haystack Butte on the test range at Edwards AFB, California.The X-33 vehicle is then (hypothetically) raised into position, fueled, and launched, making its roll maneuver and then proceeding on its flightpath.

  16. The Effects of Dimensionality in Computer Graphics.

    ERIC Educational Resources Information Center

    Addo, Theophilus B. A.

    1994-01-01

    Investigates how the dimensionality of computer-generated graphs affects users' abilities to extract information from the graphs. Finds two-dimensional graphs more reliable in communicating information quickly and accurately than corresponding three-dimensional graphs. Notes that a commonly used, but technically incorrect, three-dimensional graph…

  17. X-33 Launch - Computer generated graphic

    NASA Technical Reports Server (NTRS)

    1996-01-01

    This 45-second computer-generated launch sequence begins with a view of the X-33 launch facility located near Haystack Butte on the test range at Edwards AFB, California.The X-33 vehicle is then (hypothetically) raised into position, fueled, and launched, making its roll maneuver and then proceeding on its flightpath.

  18. 3D dynamic computer model of the head-neck complex.

    PubMed

    Sierra, Daniel A; Enderle, John D

    2006-01-01

    A 3D dynamic computer model for the movement of the head is presented that incorporates anatomically correct information about the diverse elements forming the system. The skeleton is considered as a set of interconnected rigid 3D bodies following the Newton-Euler laws of movement. The muscles are modeled using Enderle's linear model. Finally, the soft tissues, namely the ligaments, intervertebral disks, and zigapophysial joints, are modeled using the finite elements approach. The model is intended to study the neural network that controls movement and maintains the balance of the head-neck complex during eye movements.

  19. A remote computer graphics user at General Motors

    NASA Technical Reports Server (NTRS)

    Murphy, H. S.

    1982-01-01

    The successful use of automotive body surface design data is described. This data has been originally created elsewhere in GM's two large computer graphics systems of CADANCE and Fisher Graphics. As a supplier exterior lighting components, radiator grilles, energy absorbing soft faced bumper systems, and other associated items, Guide has become most dependent on the corporate computer graphics systems to supply accurate car body styling and sheet metal surfacing information for the design of their products. The presentation includes the origin and transfer of design data to a remote user site; its use in the design of their products; and the ultimate production of detailed drawings, N/C punched tapes, and subsequent downstream transfers of detailed part data to a turnkey system for tool design purposes.

  20. A remote computer graphics user at General Motors

    NASA Technical Reports Server (NTRS)

    Murphy, H. S.

    1982-01-01

    The successful use of automotive body surface design data is described. This data has been originally created elsewhere in GM's two large computer graphics systems of CADANCE and Fisher Graphics. As a supplier exterior lighting components, radiator grilles, energy absorbing soft faced bumper systems, and other associated items, Guide has become most dependent on the corporate computer graphics systems to supply accurate car body styling and sheet metal surfacing information for the design of their products. The presentation includes the origin and transfer of design data to a remote user site; its use in the design of their products; and the ultimate production of detailed drawings, N/C punched tapes, and subsequent downstream transfers of detailed part data to a turnkey system for tool design purposes.

  1. 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.

  2. Synesthetic art through 3-D projection: The requirements of a computer-based supermedium

    NASA Technical Reports Server (NTRS)

    Mallary, Robert

    1989-01-01

    A computer-based form of multimedia art is proposed that uses the computer to fuse aspects of painting, sculpture, dance, music, film, and other media into a one-to-one synthesia of image and sound for spatially synchronous 3-D projection. Called synesthetic art, this conversion of many varied media into an aesthetically unitary experience determines the character and requirements of the system and its software. During the start-up phase, computer stereographic systems are unsuitable for software development. Eventually, a new type of illusory-projective supermedium will be required to achieve the needed combination of large-format projection and convincing real life presence, and to handle the vast amount of 3-D visual and acoustic information required. The influence of the concept on the author's research and creative work is illustrated through two examples.

  3. Computational study of 3-D hot-spot initiation in shocked insensitive high-explosive

    NASA Astrophysics Data System (ADS)

    Najjar, F. M.; Howard, W. M.; Fried, L. E.; Manaa, M. R.; Nichols, A., III; Levesque, G.

    2012-03-01

    High-explosive (HE) material consists of large-sized grains with micron-sized embedded impurities and pores. Under various mechanical/thermal insults, these pores collapse generating hightemperature regions leading to ignition. A hydrodynamic study has been performed to investigate the mechanisms of pore collapse and hot spot initiation in TATB crystals, employing a multiphysics code, ALE3D, coupled to the chemistry module, Cheetah. This computational study includes reactive dynamics. Two-dimensional high-resolution large-scale meso-scale simulations have been performed. The parameter space is systematically studied by considering various shock strengths, pore diameters and multiple pore configurations. Preliminary 3-D simulations are undertaken to quantify the 3-D dynamics.

  4. Application of the ASP3D Computer Program to Unsteady Aerodynamic and Aeroelastic Analyses

    NASA Technical Reports Server (NTRS)

    Batina, John T.

    2006-01-01

    A new computer program has been developed called ASP3D (Advanced Small Perturbation - 3D), which solves the small perturbation potential flow equation in an advanced form including mass-consistent surface and trailing wake boundary conditions, and entropy, vorticity, and viscous effects. The purpose of the program is for unsteady aerodynamic and aeroelastic analyses, especially in the nonlinear transonic flight regime. The program exploits the simplicity of stationary Cartesian meshes with the movement or deformation of the configuration under consideration incorporated into the solution algorithm through a planar surface boundary condition. The paper presents unsteady aerodynamic and aeroelastic applications of ASP3D to assess the time dependent capability and demonstrate various features of the code.

  5. Organ printing: computer-aided jet-based 3D tissue engineering.

    PubMed

    Mironov, Vladimir; Boland, Thomas; Trusk, Thomas; Forgacs, Gabor; Markwald, Roger R

    2003-04-01

    Tissue engineering technology promises to solve the organ transplantation crisis. However, assembly of vascularized 3D soft organs remains a big challenge. Organ printing, which we define as computer-aided, jet-based 3D tissue-engineering of living human organs, offers a possible solution. Organ printing involves three sequential steps: pre-processing or development of "blueprints" for organs; processing or actual organ printing; and postprocessing or organ conditioning and accelerated organ maturation. A cell printer that can print gels, single cells and cell aggregates has been developed. Layer-by-layer sequentially placed and solidified thin layers of a thermo-reversible gel could serve as "printing paper". Combination of an engineering approach with the developmental biology concept of embryonic tissue fluidity enables the creation of a new rapid prototyping 3D organ printing technology, which will dramatically accelerate and optimize tissue and organ assembly.

  6. An investigation of low-dose 3D scout scans for computed tomography

    NASA Astrophysics Data System (ADS)

    Gomes, Juliana; Gang, Grace J.; Mathews, Aswin; Stayman, J. Webster

    2017-03-01

    Purpose: Commonly 2D scouts or topograms are used prior to CT scan acquisition. However, low-dose 3D scouts could potentially provide additional information for more effective patient positioning and selection of acquisition protocols. We propose using model-based iterative reconstruction to reconstruct low exposure tomographic data to maintain image quality in both low-dose 3D scouts and reprojected topograms based on those 3D scouts. Methods: We performed tomographic acquisitions on a CBCT test-bench using a range of exposure settings from 16.6 to 231.9 total mAs. Both an anthropomorphic phantom and a 32 cm CTDI phantom were scanned. The penalized-likelihood reconstructions were made using Matlab and CUDA libraries and reconstruction parameters were tuned to determine the best regularization strength and delta parameter. RMS error between reconstructions and the highest exposure reconstruction were computed, and CTDIW values were reported for each exposure setting. RMS error for reprojected topograms were also computed. Results: We find that we are able to produce low-dose (0.417 mGy) 3D scouts that show high-contrast and large anatomical features while maintaining the ability to produce traditional topograms. Conclusions: We demonstrated that iterative reconstruction can mitigate noise in very low exposure CT acquisitions to enable 3D CT scout. Such additional 3D information may lead to improved protocols for patient positioning and acquisition refinements as well as a number of advanced dose reduction strategies that require localization of anatomical features and quantities that are not provided by simple 2D topograms.

  7. Analysis of 3-D images of dental imprints using computer vision

    NASA Astrophysics Data System (ADS)

    Aubin, Michele; Cote, Jean; Laurendeau, Denis; Poussart, Denis

    1992-05-01

    This paper addressed two important aspects of dental analysis: (1) location and (2) identification of the types of teeth by means of 3-D image acquisition and segmentation. The 3-D images of both maxillaries are acquired using a wax wafer as support. The interstices between teeth are detected by non-linear filtering of the 3-D and grey-level data. Two operators are presented: one for the detection of the interstices between incisors, canines, and premolars and one for those between molars. Teeth are then identified by mapping the imprint under analysis on the computer model of an 'ideal' imprint. For the mapping to be valid, a set of three reference points is detected on the imprint. Then, the points are put in correspondence with similar points on the model. Two such points are chosen based on a least-squares fit of a second-order polynomial of the 3-D data in the area of canines. This area is of particular interest since the canines show a very characteristic shape and are easily detected on the imprint. The mapping technique is described in detail in the paper as well as pre-processing of the 3-D profiles. Experimental results are presented for different imprints.

  8. Learning with Interactive Computer Graphics in the Undergraduate Neuroscience Classroom

    PubMed Central

    Pani, John R.; Chariker, Julia H.; Naaz, Farah; Mattingly, William; Roberts, Joshua; Sephton, Sandra E.

    2014-01-01

    Instruction of neuroanatomy depends on graphical representation and extended self-study. As a consequence, computer-based learning environments that incorporate interactive graphics should facilitate instruction in this area. The present study evaluated such a system in the undergraduate neuroscience classroom. The system used the method of adaptive exploration, in which exploration in a high fidelity graphical environment is integrated with immediate testing and feedback in repeated cycles of learning. The results of this study were that students considered the graphical learning environment to be superior to typical classroom materials used for learning neuroanatomy. Students managed the frequency and duration of study, test, and feedback in an efficient and adaptive manner. For example, the number of tests taken before reaching a minimum test performance of 90% correct closely approximated the values seen in more regimented experimental studies. There was a wide range of student opinion regarding the choice between a simpler and a more graphically compelling program for learning sectional anatomy. Course outcomes were predicted by individual differences in the use of the software that reflected general work habits of the students, such as the amount of time committed to testing. The results of this introduction into the classroom are highly encouraging for development of computer-based instruction in biomedical disciplines. PMID:24449123

  9. Learning with interactive computer graphics in the undergraduate neuroscience classroom.

    PubMed

    Pani, John R; Chariker, Julia H; Naaz, Farah; Mattingly, William; Roberts, Joshua; Sephton, Sandra E

    2014-10-01

    Instruction of neuroanatomy depends on graphical representation and extended self-study. As a consequence, computer-based learning environments that incorporate interactive graphics should facilitate instruction in this area. The present study evaluated such a system in the undergraduate neuroscience classroom. The system used the method of adaptive exploration, in which exploration in a high fidelity graphical environment is integrated with immediate testing and feedback in repeated cycles of learning. The results of this study were that students considered the graphical learning environment to be superior to typical classroom materials used for learning neuroanatomy. Students managed the frequency and duration of study, test, and feedback in an efficient and adaptive manner. For example, the number of tests taken before reaching a minimum test performance of 90 % correct closely approximated the values seen in more regimented experimental studies. There was a wide range of student opinion regarding the choice between a simpler and a more graphically compelling program for learning sectional anatomy. Course outcomes were predicted by individual differences in the use of the software that reflected general work habits of the students, such as the amount of time committed to testing. The results of this introduction into the classroom are highly encouraging for development of computer-based instruction in biomedical disciplines.

  10. Simulation of Robot Kinematics Using Interactive Computer Graphics.

    ERIC Educational Resources Information Center

    Leu, M. C.; Mahajan, R.

    1984-01-01

    Development of a robot simulation program based on geometric transformation softwares available in most computer graphics systems and program features are described. The program can be extended to simulate robots coordinating with external devices (such as tools, fixtures, conveyors) using geometric transformations to describe the…

  11. KINPLOT: An Interactive Pharmacokinetics Graphics Program for Digital Computers.

    ERIC Educational Resources Information Center

    Wilson, Robert C.; And Others

    1982-01-01

    Inability to see the relevance of mathematics to understanding the time course of drugs in the body may discourage interest in pharmacokinetics. A UNC-developed computer graphics simulation program helps visualize the nature of pharmacokinetic-patient interactions, generates classroom handouts, and is used in the pharmaceuticals industry to…

  12. A "Service-Learning Approach" to Teaching Computer Graphics

    ERIC Educational Resources Information Center

    Hutzel, Karen

    2007-01-01

    The author taught a computer graphics course through a service-learning framework to undergraduate and graduate students in the spring of 2003 at Florida State University (FSU). The students in this course participated in learning a software program along with youths from a neighboring, low-income, primarily African-American community. Together,…

  13. Role of Computer Graphics in Simulations for Teaching Physiology.

    ERIC Educational Resources Information Center

    Modell, H. I.; And Others

    1983-01-01

    Discusses a revision of existing respiratory physiology simulations to promote active learning experiences for individual students. Computer graphics were added to aid student's conceptualization of the physiological system. Specific examples are provided, including those dealing with alveolar gas equations and effects of anatomic shunt flow on…

  14. AEDPS Computer Graphics Specification and Drawing Production Study.

    DTIC Science & Technology

    The purpose of this report is to present the results of the study of the current and planned Automated Engineering Document Preparation System ( AEDPS ...graphics subsystem as it would interface with AEDPS as currently operational. Since all computer systems have inputs, software and outputs - each of these

  15. Digital-Computer Processing of Graphical Data. Final Report.

    ERIC Educational Resources Information Center

    Freeman, Herbert

    The final report of a two-year study concerned with the digital-computer processing of graphical data. Five separate investigations carried out under this study are described briefly, and a detailed bibliography, complete with abstracts, is included in which are listed the technical papers and reports published during the period of this program.…

  16. KINPLOT: An Interactive Pharmacokinetics Graphics Program for Digital Computers.

    ERIC Educational Resources Information Center

    Wilson, Robert C.; And Others

    1982-01-01

    Inability to see the relevance of mathematics to understanding the time course of drugs in the body may discourage interest in pharmacokinetics. A UNC-developed computer graphics simulation program helps visualize the nature of pharmacokinetic-patient interactions, generates classroom handouts, and is used in the pharmaceuticals industry to…

  17. Computer-Graphics and the Literary Construct: A Learning Method.

    ERIC Educational Resources Information Center

    Henry, Avril

    2002-01-01

    Describes an undergraduate student module that was developed at the University of Exeter (United Kingdom) in which students made their own computer graphics to discover and to describe literary structures in texts of their choice. Discusses learning outcomes and refers to the Web site that shows students' course work. (Author/LRW)

  18. A computer graphics program for general finite element analyses

    NASA Technical Reports Server (NTRS)

    Thornton, E. A.; Sawyer, L. M.

    1978-01-01

    Documentation for a computer graphics program for displays from general finite element analyses is presented. A general description of display options and detailed user instructions are given. Several plots made in structural, thermal and fluid finite element analyses are included to illustrate program options. Sample data files are given to illustrate use of the program.

  19. Simulation of Robot Kinematics Using Interactive Computer Graphics.

    ERIC Educational Resources Information Center

    Leu, M. C.; Mahajan, R.

    1984-01-01

    Development of a robot simulation program based on geometric transformation softwares available in most computer graphics systems and program features are described. The program can be extended to simulate robots coordinating with external devices (such as tools, fixtures, conveyors) using geometric transformations to describe the…

  20. A "Service-Learning Approach" to Teaching Computer Graphics

    ERIC Educational Resources Information Center

    Hutzel, Karen

    2007-01-01

    The author taught a computer graphics course through a service-learning framework to undergraduate and graduate students in the spring of 2003 at Florida State University (FSU). The students in this course participated in learning a software program along with youths from a neighboring, low-income, primarily African-American community. Together,…

  1. A Computer-Based Graphics Course and Students' Cognitive Skills.

    ERIC Educational Resources Information Center

    Cookman, Claude

    1998-01-01

    Argues that integration of computer experiences into a visual communications course and a computerized publications design course engages students' higher cognitive skills. Describes a unit on informational graphics, and uses three theoretical perspectives (cognitive apprenticeship, seven principles of good practice, and Bloom's taxonomy) to…

  2. A Practical Introduction to Authoring for Computer-Assisted Instruction. Part 7: Graphic Support.

    ERIC Educational Resources Information Center

    Barker, P.; Skipper, T.

    1986-01-01

    Discusses ways of providing graphic support in computer-based learning environments, outlines a simple case study involving a situation requiring graphic support, and describes several author language/systems that contain facilities to support the use of graphics. (MBR)

  3. 3D-Printed Tissue-Mimicking Phantoms for Medical Imaging and Computational Validation Applications

    PubMed Central

    Shahmirzadi, Danial; Li, Ronny X.; Doyle, Barry J.; Konofagou, Elisa E.; McGloughlin, Tim M.

    2014-01-01

    Abstract Abdominal aortic aneurysm (AAA) is a permanent, irreversible dilation of the distal region of the aorta. Recent efforts have focused on improved AAA screening and biomechanics-based failure prediction. Idealized and patient-specific AAA phantoms are often employed to validate numerical models and imaging modalities. To produce such phantoms, the investment casting process is frequently used, reconstructing the 3D vessel geometry from computed tomography patient scans. In this study the alternative use of 3D printing to produce phantoms is investigated. The mechanical properties of flexible 3D-printed materials are benchmarked against proven elastomers. We demonstrate the utility of this process with particular application to the emerging imaging modality of ultrasound-based pulse wave imaging, a noninvasive diagnostic methodology being developed to obtain regional vascular wall stiffness properties, differentiating normal and pathologic tissue in vivo. Phantom wall displacements under pulsatile loading conditions were observed, showing good correlation to fluid–structure interaction simulations and regions of peak wall stress predicted by finite element analysis. 3D-printed phantoms show a strong potential to improve medical imaging and computational analysis, potentially helping bridge the gap between experimental and clinical diagnostic tools. PMID:28804733

  4. Effectiveness of Generalized Aurora Computed Tomography for the EISCAT_3D project

    NASA Astrophysics Data System (ADS)

    Tanaka, Y.; Ogawa, Y.; Kadokura, A.; Aso, T.; Ueno, G.; Saita, S.; Gustavsson, B.; Brandstrom, U.

    2013-12-01

    Aurora Computed Tomography (ACT) is a technique to reconstruct three-dimensional (3-D) distribution of auroral luminosity from a number of monochromatic images taken simultaneously by multi observation points. We have developed a more generalized ACT (hereinafter referred to as G-ACT), which is capable of retrieving energy and spatial distributions of auroral precipitating electrons from multi-instrument data, such as ionospheric electron density from the EISCAT radar, cosmic noise absorption (CNA) from imaging riometer, as well as the auroral images. On the other hand, next-generation incoherent scatter radar, EISCAT_3D, which will be a new multiple site phased-array radar, is planned to replace the existing EISCAT radars in the near future. The EISCAT_3D radar will be able to measure the 3-D ionospheric plasma parameters such as electron density and vector ion drift velocity at ten-times higher temporal and spatial resolution than the present radars and thus is expected to provide new insights into auroral physics. Detailed information of the EISCAT_3D project is described in the web page http://www.eiscat3d.se. The 3-D data measured with the EISCAT_3D radar will be a most interesting target for the application of the G-ACT method. In order to examine how effective G-ACT will be for the EISCAT_3D project, we have conducted numerical simulations. It was assumed for this simulation that (1) monochromatic imagers at ALIS (Aurora Large Imaging System) stations were directed to the ionospheric region over Skibotn (69.35N, 20.37E), Norway, (2) the EISCAT_3D radar was installed at Skibotn and observed the volume from 68.6 to 69.4N latitude and 18.8 to 21.8E longitude with multiple beams, and (3) two neighboring discrete arcs appeared over Skibotn. We first obtained data observed with the ALIS imagers and the EISCAT_3D radar by solving the forward problem and then applied the G-ACT method to these data. It was demonstrated that even if the spatial distribution of the

  5. A computer graphics pilot project - Spacecraft mission support with an interactive graphics workstation

    NASA Technical Reports Server (NTRS)

    Hagedorn, John; Ehrner, Marie-Jacqueline; Reese, Jodi; Chang, Kan; Tseng, Irene

    1986-01-01

    The NASA Computer Graphics Pilot Project was undertaken to enhance the quality control, productivity and efficiency of mission support operations at the Goddard Operations Support Computing Facility. The Project evolved into a set of demonstration programs for graphics intensive simulated control room operations, particularly in connection with the complex space missions that began in the 1980s. Complex mission mean more data. Graphic displays are a means to reduce the probabilities of operator errors. Workstations were selected with 1024 x 768 pixel color displays controlled by a custom VLSI chip coupled to an MC68010 chip running UNIX within a shell that permits operations through the medium of mouse-accessed pulldown window menus. The distributed workstations run off a host NAS 8040 computer. Applications of the system for tracking spacecraft orbits and monitoring Shuttle payload handling illustrate the system capabilities, noting the built-in capabilities of shifting the point of view and rotating and zooming in on three-dimensional views of spacecraft.

  6. A computer graphics pilot project - Spacecraft mission support with an interactive graphics workstation

    NASA Technical Reports Server (NTRS)

    Hagedorn, John; Ehrner, Marie-Jacqueline; Reese, Jodi; Chang, Kan; Tseng, Irene

    1986-01-01

    The NASA Computer Graphics Pilot Project was undertaken to enhance the quality control, productivity and efficiency of mission support operations at the Goddard Operations Support Computing Facility. The Project evolved into a set of demonstration programs for graphics intensive simulated control room operations, particularly in connection with the complex space missions that began in the 1980s. Complex mission mean more data. Graphic displays are a means to reduce the probabilities of operator errors. Workstations were selected with 1024 x 768 pixel color displays controlled by a custom VLSI chip coupled to an MC68010 chip running UNIX within a shell that permits operations through the medium of mouse-accessed pulldown window menus. The distributed workstations run off a host NAS 8040 computer. Applications of the system for tracking spacecraft orbits and monitoring Shuttle payload handling illustrate the system capabilities, noting the built-in capabilities of shifting the point of view and rotating and zooming in on three-dimensional views of spacecraft.

  7. User's guide to the NOZL3D and NOZLIC computer programs

    NASA Technical Reports Server (NTRS)

    Thomas, P. D.

    1980-01-01

    Complete FORTRAN listings and running instructions are given for a set of computer programs that perform an implicit numerical solution to the unsteady Navier-Stokes equations to predict the flow characteristics and performance of nonaxisymmetric nozzles. The set includes the NOZL3D program, which performs the flow computations; the NOZLIC program, which sets up the flow field initial conditions for general nozzle configurations, and also generates the computational grid for simple two dimensional and axisymmetric configurations; and the RGRIDD program, which generates the computational grid for complicated three dimensional configurations. The programs are designed specifically for the NASA-Langley CYBER 175 computer, and employ auxiliary disk files for primary data storage. Input instructions and computed results are given for four test cases that include two dimensional, three dimensional, and axisymmetric configurations.

  8. Adaptive step ODE algorithms for the 3D simulation of electric heart activity with graphics processing units.

    PubMed

    Garcia-Molla, V M; Liberos, A; Vidal, A; Guillem, M S; Millet, J; Gonzalez, A; Martinez-Zaldivar, F J; Climent, A M

    2014-01-01

    In this paper we studied the implementation and performance of adaptive step methods for large systems of ordinary differential equations systems in graphics processing units, focusing on the simulation of three-dimensional electric cardiac activity. The Rush-Larsen method was applied in all the implemented solvers to improve efficiency. We compared the adaptive methods with the fixed step methods, and we found that the fixed step methods can be faster while the adaptive step methods are better in terms of accuracy and robustness. © 2013 Elsevier Ltd. Published by Elsevier Ltd. All rights reserved.

  9. Integration of 3D anatomical data obtained by CT imaging and 3D optical scanning for computer aided implant surgery

    PubMed Central

    2011-01-01

    Background A precise placement of dental implants is a crucial step to optimize both prosthetic aspects and functional constraints. In this context, the use of virtual guiding systems has been recognized as a fundamental tool to control the ideal implant position. In particular, complex periodontal surgeries can be performed using preoperative planning based on CT data. The critical point of the procedure relies on the lack of accuracy in transferring CT planning information to surgical field through custom-made stereo-lithographic surgical guides. Methods In this work, a novel methodology is proposed for monitoring loss of accuracy in transferring CT dental information into periodontal surgical field. The methodology is based on integrating 3D data of anatomical (impression and cast) and preoperative (radiographic template) models, obtained by both CT and optical scanning processes. Results A clinical case, relative to a fully edentulous jaw patient, has been used as test case to assess the accuracy of the various steps concurring in manufacturing surgical guides. In particular, a surgical guide has been designed to place implants in the bone structure of the patient. The analysis of the results has allowed the clinician to monitor all the errors, which have been occurring step by step manufacturing the physical templates. Conclusions The use of an optical scanner, which has a higher resolution and accuracy than CT scanning, has demonstrated to be a valid support to control the precision of the various physical models adopted and to point out possible error sources. A case study regarding a fully edentulous patient has confirmed the feasibility of the proposed methodology. PMID:21338504

  10. Use of computer graphics simulation for teaching of flexible sigmoidoscopy.

    PubMed

    Baillie, J; Jowell, P; Evangelou, H; Bickel, W; Cotton, P

    1991-05-01

    The concept of simulation training in endoscopy is now well-established. The systems currently under development employ either computer graphics simulation or interactive video technology; each has its strengths and weaknesses. A flexible sigmoidoscopy training device has been designed which uses graphic routines--such as object oriented programming and double buffering--in entirely new ways. These programming techniques compensate for the limitations of currently available desk-top microcomputers. By boosting existing computer 'horsepower' with next generation coprocessors and sophisticated graphics tools such as intensity interpolation (Gouraud shading), the realism of computer simulation of flexible sigmoidoscopy is being greatly enhanced. The computer program has teaching and scoring capabilities, making it a truly interactive system. Use has been made of this ability to record, grade and store each trainee encounter in computer memory as part of a multi-center, prospective trial of simulation training being conducted currently in the USA. A new input device, a dummy endoscope, has been designed that allows application of variable resistance to the insertion tube. This greatly enhances tactile feedback, such as resistance during looping. If carefully designed trials show that computer simulation is an attractive and effective training tool, it is expected that this technology will evolve rapidly and be made widely available to trainee endoscopists.

  11. The computer simulation of 3d gas dynamics in a gas centrifuge

    NASA Astrophysics Data System (ADS)

    Borman, V. D.; Bogovalov, S. V.; Borisevich, V. D.; Tronin, I. V.; Tronin, V. N.

    2016-09-01

    We argue on the basis of the results of 2D analysis of the gas flow in gas centrifuges that a reliable calculation of the circulation of the gas and gas content in the gas centrifuge is possible only in frameworks of 3D numerical simulation of gas dynamics in the gas centrifuge (hereafter GC). The group from National research nuclear university, MEPhI, has created a computer code for 3D simulation of the gas flow in GC. The results of the computer simulations of the gas flows in GC are presented. A model Iguassu centrifuge is explored for the simulations. A nonaxisymmetric gas flow is produced due to interaction of the hypersonic rotating flow with the scoops for extraction of the product and waste flows from the GC. The scoops produce shock waves penetrating into a working camera of the GC and form spiral waves there.

  12. SALE-3D: a simplified ALE computer program for calculating three-dimensional fluid flow

    SciTech Connect

    Amsden, A.A.; Ruppel, H.M.

    1981-11-01

    This report presents a simplified numerical fluid-dynamics computing technique for calculating time-dependent flows in three dimensions. An implicit treatment of the pressure equation permits calculation of flows far subsonic without stringent constraints on the time step. In addition, the grid vertices may be moved with the fluid in Lagrangian fashion or held fixed in an Eulerian manner, or moved in some prescribed manner to give a continuous rezoning capability. This report describes the combination of Implicit Continuous-fluid Eulerian (ICE) and Arbitrary Lagrangian-Eulerian (ALE) to form the ICEd-ALE technique in the framework of the Simplified-ALE (SALE-3D) computer program, for which a general flow diagram and complete FORTRAN listing are included. Sample problems show how to modify the code for a variety of applications. SALE-3D is patterned as closely as possible on the previously reported two-dimensional SALE program.

  13. Gust Acoustics Computation with a Space-Time CE/SE Parallel 3D Solver

    NASA Technical Reports Server (NTRS)

    Wang, X. Y.; Himansu, A.; Chang, S. C.; Jorgenson, P. C. E.; Reddy, D. R. (Technical Monitor)

    2002-01-01

    The benchmark Problem 2 in Category 3 of the Third Computational Aero-Acoustics (CAA) Workshop is solved using the space-time conservation element and solution element (CE/SE) method. This problem concerns the unsteady response of an isolated finite-span swept flat-plate airfoil bounded by two parallel walls to an incident gust. The acoustic field generated by the interaction of the gust with the flat-plate airfoil is computed by solving the 3D (three-dimensional) Euler equations in the time domain using a parallel version of a 3D CE/SE solver. The effect of the gust orientation on the far-field directivity is studied. Numerical solutions are presented and compared with analytical solutions, showing a reasonable agreement.

  14. PLOT3D user's manual

    NASA Technical Reports Server (NTRS)

    Walatka, Pamela P.; Buning, Pieter G.; Pierce, Larry; Elson, Patricia A.

    1990-01-01

    PLOT3D is a computer graphics program designed to visualize the grids and solutions of computational fluid dynamics. Seventy-four functions are available. Versions are available for many systems. PLOT3D can handle multiple grids with a million or more grid points, and can produce varieties of model renderings, such as wireframe or flat shaded. Output from PLOT3D can be used in animation programs. The first part of this manual is a tutorial that takes the reader, keystroke by keystroke, through a PLOT3D session. The second part of the manual contains reference chapters, including the helpfile, data file formats, advice on changing PLOT3D, and sample command files.

  15. Computed Tomography and its Application for the 3D Characterization of Coarse Grained Meteorites

    NASA Technical Reports Server (NTRS)

    Gillies, Donald C.; Engel, H. P.; Carpenter, P. K.

    2004-01-01

    With judicious selection of parameters, computed tomography can provide high precision density data. Such data can lead to a non-destructive determination of the phases and phase distribution within large solid objects. Of particular interest is the structure of the Mundrabilla meteorite, which has 25 volumes, percent of a sulfide within a metallic meteorite. 3D digital imaging has enabled a quantitative evaluation of the distribution and contiguity of the phases to be determined.

  16. Computed Tomography and its Application for the 3D Characterization of Coarse Grained Meteorites

    NASA Technical Reports Server (NTRS)

    Gillies, Donald C.; Engel, H. P.; Carpenter, P. K.

    2004-01-01

    With judicious selection of parameters, computed tomography can provide high precision density data. Such data can lead to a non-destructive determination of the phases and phase distribution within large solid objects. Of particular interest is the structure of the Mundrabilla meteorite, which has 25 volumes, percent of a sulfide within a metallic meteorite. 3D digital imaging has enabled a quantitative evaluation of the distribution and contiguity of the phases to be determined.

  17. Validation of computational code UST3D by the example of experimental aerodynamic data

    NASA Astrophysics Data System (ADS)

    Surzhikov, S. T.

    2017-02-01

    Numerical simulation of the aerodynamic characteristics of the hypersonic vehicles X-33 and X-34 as well as spherically blunted cone is performed using the unstructured meshes. It is demonstrated that the numerical predictions obtained with the computational code UST3D are in acceptable agreement with the experimental data for approximate parameters of the geometry of the hypersonic vehicles and in excellent agreement with data for blunted cone.

  18. Effectiveness Evaluation of Force Protection Training Using Computer-Based Instruction and X3d Simulation

    DTIC Science & Technology

    2007-09-01

    to growing operational constraints accelerated by the Global War on Terror, the United States Navy is looking for alternative methods of training to...accomplished efficiently and effectively, saving the U.S. Navy time and resources while maintaining a high state of readiness. The goal of this thesis is...COMPUTER-BASED INSTRUCTION AND X3D SIMULATION Wilfredo Cruzbaez Lieutenant, United States Navy B.A., Norfolk State University, 2001 Submitted in

  19. Comparison of traditional methods with 3D computer models in the instruction of hepatobiliary anatomy.

    PubMed

    Keedy, Alexander W; Durack, Jeremy C; Sandhu, Parmbir; Chen, Eric M; O'Sullivan, Patricia S; Breiman, Richard S

    2011-01-01

    This study was designed to determine whether an interactive three-dimensional presentation depicting liver and biliary anatomy is more effective for teaching medical students than a traditional textbook format presentation of the same material. Forty-six medical students volunteered for participation in this study. Baseline demographic information, spatial ability, and knowledge of relevant anatomy were measured. Participants were randomized into two groups and presented with a computer-based interactive learning module comprised of animations and still images to highlight various anatomical structures (3D group), or a computer-based text document containing the same images and text without animation or interactive features (2D group). Following each teaching module, students completed a satisfaction survey and nine-item anatomic knowledge post-test. The 3D group scored higher on the post-test than the 2D group, with a mean score of 74% and 64%, respectively; however, when baseline differences in pretest scores were accounted for, this difference was not statistically significant (P = 0.33). Spatial ability did not statistically significantly correlate with post-test scores for the 3D group or the 2D group. In the post-test satisfaction survey the 3D group expressed a statistically significantly higher overall satisfaction rating compared to students in the 2D control group (4.5 versus 3.7 out of 5, P = 0.02). While the interactive 3D multimedia module received higher satisfaction ratings from students, it neither enhanced nor inhibited learning of complex hepatobiliary anatomy compared to an informationally equivalent traditional textbook style approach. . Copyright © 2011 American Association of Anatomists.

  20. Improving accuracy and computation time of 3D reconstruction through an improved carving procedure

    NASA Astrophysics Data System (ADS)

    Ruiz, Diego; Macq, Benoit

    2005-01-01

    A growing number of mixed reality applications have to build 3D models of arbitrary shapes. However, modeling of an arbitrary shape implies a trade-off between accuracy and computation time. Real-time methods based on the visual hull cannot model the holes of the shape inside the approximated silhouette. Carving methods can but they are not real time. The aim of this paper is to improve their accuracy and computation time. It presents a novel multiresolution algorithm for 3D reconstruction of arbitrary 3D shapes from range data acquired at fixed viewpoints. The algorithm is split into two parts. The first part labels a voxel thanks to the current viewpoint and without taking into account previous labels. The second part updates the labels and grows the octree representing the voxelized space. It determines the number of calls made to the first part, which is time consuming. A novel set of labels, the study of the parallelepiped projections and a front to back propagation of information allow us to improve accuracy in both parts, to reduce the computation cost of the voxel labeling part and to reduce the number of calls made to it by the mutiresolution and voxel updating part.

  1. Improving accuracy and computation time of 3D reconstruction through an improved carving procedure

    NASA Astrophysics Data System (ADS)

    Ruiz, Diego; Macq, Benoît

    2004-12-01

    A growing number of mixed reality applications have to build 3D models of arbitrary shapes. However, modeling of an arbitrary shape implies a trade-off between accuracy and computation time. Real-time methods based on the visual hull cannot model the holes of the shape inside the approximated silhouette. Carving methods can but they are not real time. The aim of this paper is to improve their accuracy and computation time. It presents a novel multiresolution algorithm for 3D reconstruction of arbitrary 3D shapes from range data acquired at fixed viewpoints. The algorithm is split into two parts. The first part labels a voxel thanks to the current viewpoint and without taking into account previous labels. The second part updates the labels and grows the octree representing the voxelized space. It determines the number of calls made to the first part, which is time consuming. A novel set of labels, the study of the parallelepiped projections and a front to back propagation of information allow us to improve accuracy in both parts, to reduce the computation cost of the voxel labeling part and to reduce the number of calls made to it by the mutiresolution and voxel updating part.

  2. Three-dimensional computer graphics for surgical procedure learning: Web three-dimensional application for cleft lip repair.

    PubMed

    Kobayashi, Masahiro; Nakajima, Tatsuo; Mori, Ayako; Tanaka, Daigo; Fujino, Toyomi; Chiyokura, Hiroaki

    2006-05-01

    In surgical procedures for cleft lip, surgeons attempt to use various skin incisions and small flaps to achieve a better and more natural shape postoperatively. They must understand the three-dimensional (3D) structure of the lips. However, they may have difficulty learning the surgical procedures precisely from normal textbooks with two-dimensional illustrations. Recent developments in 3D computed tomography (3D-CT) and laser stereolithography have enabled surgeons to visualize the structures of cleft lips from desired viewpoints. However, this method cannot reflect the advantages offered by specific surgical procedures. To solve this problem, we used the benefits offered by 3D computer graphics (3D-CG) and 3D animation. By using scanning 3D-CT image data of patients with cleft lips, 3D-CG models of the cleft lips were created. Several animations for surgical procedures such as incision designs, rotation of small skin flaps, and sutures were made. This system can recognize the details of an operation procedure clearly from any viewpoint, which cannot be acquired from the usual textbook illustrations. This animation system can be used for developing new skin-flap design, understanding the operational procedure, and using tools in case presentations. The 3D animations can also be uploaded to the World Wide Web for use in teleconferencing.

  3. Computer assisted 3D pre-operative planning tool for femur fracture orthopedic surgery

    NASA Astrophysics Data System (ADS)

    Gamage, Pavan; Xie, Sheng Quan; Delmas, Patrice; Xu, Wei Liang

    2010-02-01

    Femur shaft fractures are caused by high impact injuries and can affect gait functionality if not treated correctly. Until recently, the pre-operative planning for femur fractures has relied on two-dimensional (2D) radiographs, light boxes, tracing paper, and transparent bone templates. The recent availability of digital radiographic equipment has to some extent improved the workflow for preoperative planning. Nevertheless, imaging is still in 2D X-rays and planning/simulation tools to support fragment manipulation and implant selection are still not available. Direct three-dimensional (3D) imaging modalities such as Computed Tomography (CT) are also still restricted to a minority of complex orthopedic procedures. This paper proposes a software tool which allows orthopedic surgeons to visualize, diagnose, plan and simulate femur shaft fracture reduction procedures in 3D. The tool utilizes frontal and lateral 2D radiographs to model the fracture surface, separate a generic bone into the two fractured fragments, identify the pose of each fragment, and automatically customize the shape of the bone. The use of 3D imaging allows full spatial inspection of the fracture providing different views through the manipulation of the interactively reconstructed 3D model, and ultimately better pre-operative planning.

  4. A 3D learning playground for potential attention training in ADHD: A brain computer interface approach.

    PubMed

    Ali, Abdulla; Puthusserypady, Sadasivan

    2015-01-01

    This paper presents a novel brain-computer-interface (BCI) system that could potentially be used for enhancing the attention ability of subjects with attention deficit hyperactivity disorder (ADHD). It employs the steady state visual evoked potential (SSVEP) paradigm. The developed system consists of a 3D classroom environment with active 3D distractions and 2D games executed on the blackboard. The system is concealed as a game (with stages of varying difficulty) with an underlying story to motivate the subjects. It was tested on eleven healthy subjects and the results undeniably establish that by moving to a higher stage in the game where the 2D environment is changed to 3D along with the added 3D distractions, the difficulty level in keeping attention on the main task increases for the subjects. Results also show a mean accuracy of 92.26 ± 7.97% and a mean average selection time of 3.07 ± 1.09 seconds.

  5. A User-Developed 3-D Hand Gesture Set for Human-Computer Interaction.

    PubMed

    Pereira, Anna; Wachs, Juan P; Park, Kunwoo; Rempel, David

    2015-06-01

    The purpose of this study was to develop a lexicon for 3-D hand gestures for common human-computer interaction (HCI) tasks by considering usability and effort ratings. Recent technologies create an opportunity for developing a free-form 3-D hand gesture lexicon for HCI. Subjects (N = 30) with prior experience using 2-D gestures on touch screens performed 3-D gestures of their choice for 34 common HCI tasks and rated their gestures on preference, match, ease, and effort. Videos of the 1,300 generated gestures were analyzed for gesture popularity, order, and response times. Gesture hand postures were rated by the authors on biomechanical risk and fatigue. A final task gesture set is proposed based primarily on subjective ratings and hand posture risk. The different dimensions used for evaluating task gestures were not highly correlated and, therefore, measured different properties of the task-gesture match. A method is proposed for generating a user-developed 3-D gesture lexicon for common HCIs that involves subjective ratings and a posture risk rating for minimizing arm and hand fatigue. © 2014, Human Factors and Ergonomics Society.

  6. Computer-aided planning and reconstruction of cranial 3D implants.

    PubMed

    Gall, Markus; Xing Li; Xiaojun Chen; Schmalstieg, Dieter; Egger, Jan

    2016-08-01

    In this contribution, a prototype for semiautomatic computer-aided planning and reconstruction of cranial 3D Implants is presented. The software prototype guides the user through the workflow, beginning with loading and mirroring the patient's head to obtain an initial curvature of the cranial implant. However, naïve mirroring is not sufficient for an implant, because human heads are in general too asymmetric. Thus, the user can perform Laplacian smoothing, followed by Delaunay triangulation, for generating an aesthetic looking and well-fitting implant. Finally, our software prototype allows to save the designed 3D model of the implant as a STL-file for 3D printing. The 3D printed implant can be used for further pre-interventional planning or even as the final implant for the patient. In summary, our findings show that a customized MeVisLab prototype can be an alternative to complex commercial planning software, which may not be available in a clinic.

  7. [3D modeling of the female pelvis by Computer-Assisted Anatomical Dissection: Applications and perspectives].

    PubMed

    Balaya, V; Uhl, J-F; Lanore, A; Salachas, C; Samoyeau, T; Ngo, C; Bensaid, C; Cornou, C; Rossi, L; Douard, R; Bats, A-S; Lecuru, F; Delmas, V

    2016-05-01

    To achieve a 3D vectorial model of a female pelvis by Computer-Assisted Anatomical Dissection and to assess educationnal and surgical applications. From the database of "visible female" of Visible Human Project(®) (VHP) of the "national library of medicine" NLM (United States), we used 739 transverse anatomical slices of 0.33mm thickness going from L4 to the trochanters. The manual segmentation of each anatomical structures was done with Winsurf(®) software version 4.3. Each anatomical element was built as a separate vectorial object. The whole colored-rendered vectorial model with realistic textures was exported in 3Dpdf format to allow a real time interactive manipulation with Acrobat(®) pro version 11 software. Each element can be handled separately at any transparency, which allows an anatomical learning by systems: skeleton, pelvic organs, urogenital system, arterial and venous vascularization. This 3D anatomical model can be used as data bank to teach of the fundamental anatomy. This 3D vectorial model, realistic and interactive constitutes an efficient educational tool for the teaching of the anatomy of the pelvis. 3D printing of the pelvis is possible with the new printers. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  8. THERM3D -- A boundary element computer program for transient heat conduction problems

    SciTech Connect

    Ingber, M.S.

    1994-02-01

    The computer code THERM3D implements the direct boundary element method (BEM) to solve transient heat conduction problems in arbitrary three-dimensional domains. This particular implementation of the BEM avoids performing time-consuming domain integrations by approximating a ``generalized forcing function`` in the interior of the domain with the use of radial basis functions. An approximate particular solution is then constructed, and the original problem is transformed into a sequence of Laplace problems. The code is capable of handling a large variety of boundary conditions including isothermal, specified flux, convection, radiation, and combined convection and radiation conditions. The computer code is benchmarked by comparisons with analytic and finite element results.

  9. 3-D heat transfer computer calculations of the performance of the IAEA's air-bath calorimeters

    SciTech Connect

    Elias, E.; Kaizermann, S.; Perry, R.B.; Fiarman, S.

    1989-01-01

    A three dimensional (3-D) heat transfer computer code was developed to study and optimize the design parameters and to better understand the performance characteristics of the IAEA's air-bath calorimeters. The computer model accounts for heat conduction and radiation in the complex materials of the calorimeter and for heat convection and radiation at its outer surface. The temperature servo controller is modelled as an integral part of the heat balance equations in the system. The model predictions will be validated against test data using the ANL bulk calorimeter. 11 refs., 6 figs.

  10. Full 3-D OCT-based pseudophakic custom computer eye model

    PubMed Central

    Sun, M.; Pérez-Merino, P.; Martinez-Enriquez, E.; Velasco-Ocana, M.; Marcos, S.

    2016-01-01

    We compared measured wave aberrations in pseudophakic eyes implanted with aspheric intraocular lenses (IOLs) with simulated aberrations from numerical ray tracing on customized computer eye models, built using quantitative 3-D OCT-based patient-specific ocular geometry. Experimental and simulated aberrations show high correlation (R = 0.93; p<0.0001) and similarity (RMS for high order aberrations discrepancies within 23.58%). This study shows that full OCT-based pseudophakic custom computer eye models allow understanding the relative contribution of optical geometrical and surgically-related factors to image quality, and are an excellent tool for characterizing and improving cataract surgery. PMID:27231608

  11. Computation of an Underexpanded 3-D Rectangular Jet by the CE/SE Method

    NASA Technical Reports Server (NTRS)

    Loh, Ching Y.; Himansu, Ananda; Wang, Xiao Y.; Jorgenson, Philip C. E.

    2000-01-01

    Recently, an unstructured three-dimensional space-time conservation element and solution element (CE/SE) Euler solver was developed. Now it is also developed for parallel computation using METIS for domain decomposition and MPI (message passing interface). The method is employed here to numerically study the near-field of a typical 3-D rectangular under-expanded jet. For the computed case-a jet with Mach number Mj = 1.6. with a very modest grid of 1.7 million tetrahedrons, the flow features such as the shock-cell structures and the axis switching, are in good qualitative agreement with experimental results.

  12. Distributed network, wireless and cloud computing enabled 3-D ultrasound; a new medical technology paradigm.

    PubMed

    Meir, Arie; Rubinsky, Boris

    2009-11-19

    Medical technologies are indispensable to modern medicine. However, they have become exceedingly expensive and complex and are not available to the economically disadvantaged majority of the world population in underdeveloped as well as developed parts of the world. For example, according to the World Health Organization about two thirds of the world population does not have access to medical imaging. In this paper we introduce a new medical technology paradigm centered on wireless technology and cloud computing that was designed to overcome the problems of increasing health technology costs. We demonstrate the value of the concept with an example; the design of a wireless, distributed network and central (cloud) computing enabled three-dimensional (3-D) ultrasound system. Specifically, we demonstrate the feasibility of producing a 3-D high end ultrasound scan at a central computing facility using the raw data acquired at the remote patient site with an inexpensive low end ultrasound transducer designed for 2-D, through a mobile device and wireless connection link between them. Producing high-end 3D ultrasound images with simple low-end transducers reduces the cost of imaging by orders of magnitude. It also removes the requirement of having a highly trained imaging expert at the patient site, since the need for hand-eye coordination and the ability to reconstruct a 3-D mental image from 2-D scans, which is a necessity for high quality ultrasound imaging, is eliminated. This could enable relatively untrained medical workers in developing nations to administer imaging and a more accurate diagnosis, effectively saving the lives of people.

  13. The Use of 3D Graphic Modelling in Geoarchaeological Investigations (Bykowszczyzna Archaeological Site near Kock, E Poland)

    NASA Astrophysics Data System (ADS)

    Łojek, Jacek

    2012-01-01

    The objective of this paper was to use the ArcView 3.2 application for spatial modelling of the exploration forms (pits) in the Bykowszczyzna 8 archaeological site. The 3D digital documentation at a specific scale makes possible easy archiving, presentation, and simple spatial analyses of the examined objects. The ArcView 3.2 programme and its extensions (Spatial Analyst and 3D Analyst), commonly used as analytical tools in geomorphology, were inventively used for inventory-making in the archaeological site. Traditional field sketches were only a base, which enables entering data into the programme, and don't documentation material in itself as it used to be. The method of data visual ization proposed by the author gives new possibilities for using the GIS platform software. W artykule zaprezentowano projekt wykorzystania aplikacji ArcView 3.2 w modelowaniu obrazu form eksploracyjnych na stanowisku archeologicznym Bykowszczyzna 8. Stanowisko zostało objęte programem ratowniczych badań archeologicznych w związku z budową obwodnicy miasta Kocka na trasie krajowej nr 19 relacji Siemiatycze-Lublin-Nisko. Zasadniczy etap prac archeologicznych na stanowisku Bykowszczyzna 8 obejmował pozyskanie oraz inwentaryzację materiału zabytkowego wypełniającego formy. W wyniku wybrania tego materiału, w obszarze stanowiska pozostają charakterystyczne jamy gospodarcze, które stanowią negatywowy obraz wypełnienia formy. Kształt jam jest dokumentowany w postaci szkiców oraz fotografii. Dokumentacja ta stanowi punkt wyjścia procesu digitalizacji (materiał źródłowy). Treścią artykułu jest sporządzenie cyfrowej dokumentacji zawierającej plany stanowiska w kilku poziomach szczegółowości (dla pasa, pola oraz pojedynczych form) oraz wygenerowanie modeli w standardzie 3D. Dokumentacja taka umożliwia łatwą archiwizację oraz czytelną prezentację wybranych obiektów. Możliwe jest również wykonanie analiz przestrzennych. Funkcje programu ArcView 3.2. oraz

  14. Automatic procedure for realistic 3D finite element modelling of human brain for bioelectromagnetic computations

    NASA Astrophysics Data System (ADS)

    Aristovich, K. Y.; Khan, S. H.

    2010-07-01

    Realistic computer modelling of biological objects requires building of very accurate and realistic computer models based on geometric and material data, type, and accuracy of numerical analyses. This paper presents some of the automatic tools and algorithms that were used to build accurate and realistic 3D finite element (FE) model of whole-brain. These models were used to solve the forward problem in magnetic field tomography (MFT) based on Magnetoencephalography (MEG). The forward problem involves modelling and computation of magnetic fields produced by human brain during cognitive processing. The geometric parameters of the model were obtained from accurate Magnetic Resonance Imaging (MRI) data and the material properties - from those obtained from Diffusion Tensor MRI (DTMRI). The 3D FE models of the brain built using this approach has been shown to be very accurate in terms of both geometric and material properties. The model is stored on the computer in Computer-Aided Parametrical Design (CAD) format. This allows the model to be used in a wide a range of methods of analysis, such as finite element method (FEM), Boundary Element Method (BEM), Monte-Carlo Simulations, etc. The generic model building approach presented here could be used for accurate and realistic modelling of human brain and many other biological objects.

  15. A hybrid method for the computation of quasi-3D seismograms.

    NASA Astrophysics Data System (ADS)

    Masson, Yder; Romanowicz, Barbara

    2013-04-01

    The development of powerful computer clusters and efficient numerical computation methods, such as the Spectral Element Method (SEM) made possible the computation of seismic wave propagation in a heterogeneous 3D earth. However, the cost of theses computations is still problematic for global scale tomography that requires hundreds of such simulations. Part of the ongoing research effort is dedicated to the development of faster modeling methods based on the spectral element method. Capdeville et al. (2002) proposed to couple SEM simulations with normal modes calculation (C-SEM). Nissen-Meyer et al. (2007) used 2D SEM simulations to compute 3D seismograms in a 1D earth model. Thanks to these developments, and for the first time, Lekic et al. (2011) developed a 3D global model of the upper mantle using SEM simulations. At the local and continental scale, adjoint tomography that is using a lot of SEM simulation can be implemented on current computers (Tape, Liu et al. 2009). Due to their smaller size, these models offer higher resolution. They provide us with images of the crust and the upper part of the mantle. In an attempt to teleport such local adjoint tomographic inversions into the deep earth, we are developing a hybrid method where SEM computation are limited to a region of interest within the earth. That region can have an arbitrary shape and size. Outside this region, the seismic wavefield is extrapolated to obtain synthetic data at the Earth's surface. A key feature of the method is the use of a time reversal mirror to inject the wavefield induced by distant seismic source into the region of interest (Robertsson and Chapman 2000). We compute synthetic seismograms as follow: Inside the region of interest, we are using regional spectral element software RegSEM to compute wave propagation in 3D. Outside this region, the wavefield is extrapolated to the surface by convolution with the Green's functions from the mirror to the seismic stations. For now, these

  16. Graphics processing unit based computation for NDE applications

    NASA Astrophysics Data System (ADS)

    Nahas, C. A.; Rajagopal, Prabhu; Balasubramaniam, Krishnan; Krishnamurthy, C. V.

    2012-05-01

    Advances in parallel processing in recent years are helping to improve the cost of numerical simulation. Breakthroughs in Graphical Processing Unit (GPU) based computation now offer the prospect of further drastic improvements. The introduction of 'compute unified device architecture' (CUDA) by NVIDIA (the global technology company based in Santa Clara, California, USA) has made programming GPUs for general purpose computing accessible to the average programmer. Here we use CUDA to develop parallel finite difference schemes as applicable to two problems of interest to NDE community, namely heat diffusion and elastic wave propagation. The implementations are for two-dimensions. Performance improvement of the GPU implementation against serial CPU implementation is then discussed.

  17. Computational methods and implementation of the 3-D PWR core dynamics SIMTRAN code for online surveillance and prediction

    SciTech Connect

    Aragones, J.M.; Ahnert, C.

    1995-12-31

    New computational methods have been developed in our 3-D PWR core dynamics SIMTRAN code for online surveillance and prediction. They improve the accuracy and efficiency of the coupled neutronic-thermalhydraulic solution and extend its scope to provide, mainly, the calculation of: the fission reaction rates at the incore mini-detectors; the responses at the excore detectors (power range); the temperatures at the thermocouple locations; and the in-vessel distribution of the loop cold-leg inlet coolant conditions in the reflector and core channels, and to the hot-leg outlets per loop. The functional capabilities implemented in the extended SIMTRAN code for online utilization include: online surveillance, incore-excore calibration, evaluation of peak power factors and thermal margins, nominal update and cycle follow, prediction of maneuvers and diagnosis of fast transients and oscillations. The new code has been installed at the Vandellos-II PWR unit in Spain, since the startup of its cycle 7 in mid-June, 1994. The computational implementation has been performed on HP-700 workstations under the HP-UX Unix system, including the machine-man interfaces for online acquisition of measured data and interactive graphical utilization, in C and X11. The agreement of the simulated results with the measured data, during the startup tests and first months of actual operation, is well within the accuracy requirements. The performance and usefulness shown during the testing and demo phase, to be extended along this cycle, has proved that SIMTRAN and the man-machine graphic user interface have the qualities for a fast, accurate, user friendly, reliable, detailed and comprehensive online core surveillance and prediction.

  18. Dimensionality of visual complexity in computer graphics scenes

    NASA Astrophysics Data System (ADS)

    Ramanarayanan, Ganesh; Bala, Kavita; Ferwerda, James A.; Walter, Bruce

    2008-02-01

    How do human observers perceive visual complexity in images? This problem is especially relevant for computer graphics, where a better understanding of visual complexity can aid in the development of more advanced rendering algorithms. In this paper, we describe a study of the dimensionality of visual complexity in computer graphics scenes. We conducted an experiment where subjects judged the relative complexity of 21 high-resolution scenes, rendered with photorealistic methods. Scenes were gathered from web archives and varied in theme, number and layout of objects, material properties, and lighting. We analyzed the subject responses using multidimensional scaling of pooled subject responses. This analysis embedded the stimulus images in a two-dimensional space, with axes that roughly corresponded to "numerosity" and "material / lighting complexity". In a follow-up analysis, we derived a one-dimensional complexity ordering of the stimulus images. We compared this ordering with several computable complexity metrics, such as scene polygon count and JPEG compression size, and did not find them to be very correlated. Understanding the differences between these measures can lead to the design of more efficient rendering algorithms in computer graphics.

  19. Graphics processing unit acceleration of computational electromagnetic methods

    NASA Astrophysics Data System (ADS)

    Inman, Matthew

    The use of Graphical Processing Units (GPU's) for scientific applications has been evolving and expanding for the decade. GPU's provide an alternative to the CPU in the creation and execution of the numerical codes that are often relied upon in to perform simulations in computational electromagnetics. While originally designed purely to display graphics on the users monitor, GPU's today are essentially powerful floating point co-processors that can be programmed not only to render complex graphics, but also perform the complex mathematical calculations often encountered in scientific computing. Currently the GPU's being produced often contain hundreds of separate cores able to access large amounts of high-speed dedicated memory. By utilizing the power offered by such a specialized processor, it is possible to drastically speed up the calculations required in computational electromagnetics. This increase in speed allows for the use of GPU based simulations in a variety of situations that the computational time has heretofore been a limiting factor in, such as in educational courses. Many situations in teaching electromagnetics often rely upon simple examples of problems due to the simulation times needed to analyze more complex problems. The use of GPU based simulations will be shown to allow demonstrations of more advanced problems than previously allowed by adapting the methods for use on the GPU. Modules will be developed for a wide variety of teaching situations utilizing the speed of the GPU to demonstrate various techniques and ideas previously unrealizable.

  20. Computed tomography measurement of 3D combustion chemiluminescence using single camera

    NASA Astrophysics Data System (ADS)

    Wang, Kuanliang; Li, Fei; Zeng, Hui; Zhang, Shaohua; Yu, Xilong

    2016-10-01

    Instantaneous measurement of flame spatial structure has been long desired for complicated combustion condition (gas turbine, ramjet et.). Three dimensional computed tomography of chemiluminescence (3D-CTC) is a potential testing technology for its simplicity, low cost, high temporal and spatial resolution. In most former studies, multi-lens and multi-CCD are used to capture projects from different view angles. In order to improve adaptability, only one CCD was utilized to build 3D-CTC system combined with customized fiber-based endoscopes (FBEs). It makes this technique more economic and simple. Validate experiments were made using 10 small CH4 diffusion flame arranging in a ring structure. Based on one instantaneous image, computed tomography can be conducted using Algebraic Reconstruction Technique (ART) algorithm. The reconstructed results, including the flame number, ring shape of the flames, the inner and outer diameter of ring, all well match the physical structure. It indicates that 3D combustion chemiluminescence could be well reconstructed using single camera.

  1. 3D histomorphometric quantification of trabecular bones by computed microtomography using synchrotron radiation.

    PubMed

    Nogueira, L P; Braz, D; Barroso, R C; Oliveira, L F; Pinheiro, C J G; Dreossi, D; Tromba, G

    2010-12-01

    Conventional bone histomorphometry is an important method for quantitative evaluation of bone microstructure. X-ray computed microtomography is a non-invasive technique, which can be used to evaluate histomorphometric indices in trabecular bones (BV/TV, BS/BV, Tb.N, Tb.Th, Tb.Sp). In this technique, 3D images are used to quantify the whole sample, differently from the conventional one, in which the quantification is performed in 2D slices and extrapolated for 3D case. In this work, histomorphometric quantification using synchrotron 3D X-ray computed microtomography was performed to quantify the bone structure at different skeletal sites as well as to investigate the effects of bone diseases on quantitative understanding of bone architecture. The images were obtained at Synchrotron Radiation for MEdical Physics (SYRMEP) beamline, at ELETTRA synchrotron radiation facility, Italy. Concerning the obtained results for normal and pathological bones from same skeletal sites and individuals, from our results, a certain declining bone volume fraction was achieved. The results obtained could be used in forming the basis for comparison of the bone microarchitecture and can be a valuable tool for predicting bone fragility. Copyright © 2010 Elsevier Ltd. All rights reserved.

  2. Design and highly accurate 3D displacement characterization of monolithic SMA microgripper using computer vision

    NASA Astrophysics Data System (ADS)

    Bellouard, Yves; Sulzmann, Armin; Jacot, Jacques; Clavel, Reymond

    1998-01-01

    In the robotics field, several grippers have been developed using SMA technologies, but, so far, SMA is only used as the actuating part of the mechanical device. However mechanical device requires assembly and in some cases this means friction. In the case of micro-grippers, this becomes a major problem due to the small size of the components. In this paper, a new monolithic concept of micro-gripper is presented. This concept is applied to the grasping of sub- millimeter optical elements such as Selfoc lenses and the fastening of optical fibers. Measurements are performed using a newly developed high precision 3D-computer vision tracking system to characterize the spatial positions of the micro-gripper in action. To characterize relative motion of the micro-gripper the natural texture of the micro-gripper is used to compute 3D displacement. The microscope image CCD receivers high frequency changes in light intensity from the surface of the ripper. Using high resolution camera calibration, passive auto focus algorithms and 2D object recognition, the position of the micro-gripper can be characterized in the 3D workspace and can be guided in future micro assembly tasks.

  3. The RNA 3D Motif Atlas: Computational methods for extraction, organization and evaluation of RNA motifs.

    PubMed

    Parlea, Lorena G; Sweeney, Blake A; Hosseini-Asanjan, Maryam; Zirbel, Craig L; Leontis, Neocles B

    2016-07-01

    RNA 3D motifs occupy places in structured RNA molecules that correspond to the hairpin, internal and multi-helix junction "loops" of their secondary structure representations. As many as 40% of the nucleotides of an RNA molecule can belong to these structural elements, which are distinct from the regular double helical regions formed by contiguous AU, GC, and GU Watson-Crick basepairs. With the large number of atomic- or near atomic-resolution 3D structures appearing in a steady stream in the PDB/NDB structure databases, the automated identification, extraction, comparison, clustering and visualization of these structural elements presents an opportunity to enhance RNA science. Three broad applications are: (1) identification of modular, autonomous structural units for RNA nanotechnology, nanobiology and synthetic biology applications; (2) bioinformatic analysis to improve RNA 3D structure prediction from sequence; and (3) creation of searchable databases for exploring the binding specificities, structural flexibility, and dynamics of these RNA elements. In this contribution, we review methods developed for computational extraction of hairpin and internal loop motifs from a non-redundant set of high-quality RNA 3D structures. We provide a statistical summary of the extracted hairpin and internal loop motifs in the most recent version of the RNA 3D Motif Atlas. We also explore the reliability and accuracy of the extraction process by examining its performance in clustering recurrent motifs from homologous ribosomal RNA (rRNA) structures. We conclude with a summary of remaining challenges, especially with regard to extraction of multi-helix junction motifs. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Utero-fetal unit and pregnant woman modeling using a computer graphics approach for dosimetry studies.

    PubMed

    Anquez, Jérémie; Boubekeur, Tamy; Bibin, Lazar; Angelini, Elsa; Bloch, Isabelle

    2009-01-01

    Potential sanitary effects related to electromagnetic fields exposure raise public concerns, especially for fetuses during pregnancy. Human fetus exposure can only be assessed through simulated dosimetry studies, performed on anthropomorphic models of pregnant women. In this paper, we propose a new methodology to generate a set of detailed utero-fetal unit (UFU) 3D models during the first and third trimesters of pregnancy, based on segmented 3D ultrasound and MRI data. UFU models are built using recent geometry processing methods derived from mesh-based computer graphics techniques and embedded in a synthetic woman body. Nine pregnant woman models have been generated using this approach and validated by obstetricians, for anatomical accuracy and representativeness.

  5. Parallel Adaptive Computation of Blood Flow in a 3D ``Whole'' Body Model

    NASA Astrophysics Data System (ADS)

    Zhou, M.; Figueroa, C. A.; Taylor, C. A.; Sahni, O.; Jansen, K. E.

    2008-11-01

    Accurate numerical simulations of vascular trauma require the consideration of a larger portion of the vasculature than previously considered, due to the systemic nature of the human body's response. A patient-specific 3D model composed of 78 connected arterial branches extending from the neck to the lower legs is constructed to effectively represent the entire body. Recently developed outflow boundary conditions that appropriately represent the downstream vasculature bed which is not included in the 3D computational domain are applied at 78 outlets. In this work, the pulsatile blood flow simulations are started on a fairly uniform, unstructured mesh that is subsequently adapted using a solution-based approach to efficiently resolve the flow features. The adapted mesh contains non-uniform, anisotropic elements resulting in resolution that conforms with the physical length scales present in the problem. The effects of the mesh resolution on the flow field are studied, specifically on relevant quantities of pressure, velocity and wall shear stress.

  6. Effect of Random Geometric Uncertainty on the Computational Design of a 3-D Flexible Wing

    NASA Technical Reports Server (NTRS)

    Gumbert, C. R.; Newman, P. A.; Hou, G. J.-W.

    2002-01-01

    The effect of geometric uncertainty due to statistically independent, random, normally distributed shape parameters is demonstrated in the computational design of a 3-D flexible wing. A first-order second-moment statistical approximation method is used to propagate the assumed input uncertainty through coupled Euler CFD aerodynamic / finite element structural codes for both analysis and sensitivity analysis. First-order sensitivity derivatives obtained by automatic differentiation are used in the input uncertainty propagation. These propagated uncertainties are then used to perform a robust design of a simple 3-D flexible wing at supercritical flow conditions. The effect of the random input uncertainties is shown by comparison with conventional deterministic design results. Sample results are shown for wing planform, airfoil section, and structural sizing variables.

  7. Computer-assisted three-dimensional surgical planning: 3D virtual articulator: technical note.

    PubMed

    Ghanai, S; Marmulla, R; Wiechnik, J; Mühling, J; Kotrikova, B

    2010-01-01

    This study presents a computer-assisted planning system for dysgnathia treatment. It describes the process of information gathering using a virtual articulator and how the splints are constructed for orthognathic surgery. The deviation of the virtually planned splints is shown in six cases on the basis of conventionally planned cases. In all cases the plaster models were prepared and scanned using a 3D laser scanner. Successive lateral and posterior-anterior cephalometric images were used for reconstruction before surgery. By identifying specific points on the X-rays and marking them on the virtual models, it was possible to enhance the 2D images to create a realistic 3D environment and to perform virtual repositioning of the jaw. A hexapod was used to transfer the virtual planning to the real splints. Preliminary results showed that conventional repositioning could be replicated using the virtual articulator.

  8. 3D image reconstruction on x-ray micro-computed tomography

    NASA Astrophysics Data System (ADS)

    Louk, Andreas C.

    2015-03-01

    A model for 3D image reconstruction of x-ray micro-computed tomography scanner (micro-CTScan) has been developed. A small object has been put under inspection on an x-ray micro-CTScan. The object cross-section was assumed on the x-y plane, while its height was along the z-axis. Using a radiography plane detector, a set of digital radiographs represents multiple angle of views from 0º to 360º with an interval of 1º was obtained. Then, a set of crosssectional tomography, slice by slice was reconstructed. At the end, all image slices were stacked together sequentially to obtain a 3D image model of the object being inspected. From this development, lessons on the way to have better understanding on the internal structure of the object can be approached based on the cross-sectional image slice by slice and surface skin.

  9. Application of 3D-computed tomography angiography technology in large meningioma resection.

    PubMed

    Chen, Jian-Qiang; Guan, Yin; Li, Gang; Li, Xiao-Hua; Zhan, Yue-Fu; Li, Xiang-Yin; Nie, Liu; Han, Xiang-Jun

    2012-07-01

    To discuss the role of 3D-computed tomography angiography (3D-CTA) technology in reducing injuries of large meningioma surgery. 3D-CTA preoperative examinations were done in 473 patients with large meningioma (simulated group). The images were analyzed by 3D post-processing workstation. By observing the major intracranial blood vessels, venous sinus, and the compression and invasion pattern in the nerve region, assessing risk level of the surgery, simulating the surgical procedures, the surgical removal plan, surgical routes and tumor blood-supplying artery embolisation plan were performed. Two hundred and fifty seven large meningioma patients who didn't underwent 3D-CTA preoperative examination served as control group. The incidence of postoperative complications, intraoperative blood transfusion and the operation time were compared between these two groups. Compared with the control group, the Simpson's grade I and II resection rate was 80.3% (380/473), similar with that of the control (81.3%, 209/257). The incidence of postoperative complications in 3D-CTA simulated group was 37.0% which was significantly lower than that (48.2%) of the control (P<0.01). The intraoperative blood supply for simulated group and the control was (523.4±208.1) mL and (592.0±263.3) mL, respectively, with significant difference between two groups (P<0.01). And the operation time [(314.8±106.3)] min was significantly lower in simulated group than that in the control [(358.4±147.9) min] (P<0.01). Application of 3D-CTA imaging technology in risk level assessment before large-scaled meningioma resection could assist in the rational planning of tumor resectin, surgical routes, and is helpful in reducing injuries and complications and enhancing the prognosis of the patients. Copyright © 2012 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

  10. Extracellular vesicles of calcifying turkey leg tendon characterized by immunocytochemistry and high voltage electron microscopic tomography and 3-D graphic image reconstruction

    NASA Technical Reports Server (NTRS)

    Landis, W. J.; Hodgens, K. J.; McKee, M. D.; Nanci, A.; Song, M. J.; Kiyonaga, S.; Arena, J.; McEwen, B.

    1992-01-01

    To gain insight into the structure and possible function of extracellular vesicles in certain calcifying vertebrate tissues, normally mineralizing leg tendons from the domestic turkey, Meleagris gallopavo, have been studied in two separate investigations, one concerning the electron microscopic immunolocalization of the 66 kDa phosphoprotein, osteopontin, and the other detailing the organization and distribution of mineral crystals associated with the vesicles as determined by high voltage microscopic tomography and 3-D graphic image reconstruction. Immunolabeling shows that osteopontin is related to extracellular vesicles of the tendon in the sense that its initial presence appears coincident with the development of mineral associated with the vesicle loci. By high voltage electron microscopy and 3-D imaging techniques, mineral crystals are found to consist of small irregularly shaped particles somewhat randomly oriented throughout individual vesicles sites. Their appearance is different from that found for the mineral observed within calcifying tendon collagen, and their 3-D disposition is not regularly ordered. Possible spatial and temporal relationships of vesicles, osteopontin, mineral, and collagen are being examined further by these approaches.

  11. Extracellular vesicles of calcifying turkey leg tendon characterized by immunocytochemistry and high voltage electron microscopic tomography and 3-D graphic image reconstruction

    NASA Technical Reports Server (NTRS)

    Landis, W. J.; Hodgens, K. J.; McKee, M. D.; Nanci, A.; Song, M. J.; Kiyonaga, S.; Arena, J.; McEwen, B.

    1992-01-01

    To gain insight into the structure and possible function of extracellular vesicles in certain calcifying vertebrate tissues, normally mineralizing leg tendons from the domestic turkey, Meleagris gallopavo, have been studied in two separate investigations, one concerning the electron microscopic immunolocalization of the 66 kDa phosphoprotein, osteopontin, and the other detailing the organization and distribution of mineral crystals associated with the vesicles as determined by high voltage microscopic tomography and 3-D graphic image reconstruction. Immunolabeling shows that osteopontin is related to extracellular vesicles of the tendon in the sense that its initial presence appears coincident with the development of mineral associated with the vesicle loci. By high voltage electron microscopy and 3-D imaging techniques, mineral crystals are found to consist of small irregularly shaped particles somewhat randomly oriented throughout individual vesicles sites. Their appearance is different from that found for the mineral observed within calcifying tendon collagen, and their 3-D disposition is not regularly ordered. Possible spatial and temporal relationships of vesicles, osteopontin, mineral, and collagen are being examined further by these approaches.

  12. Computer generated hologram from point cloud using graphics processor.

    PubMed

    Chen, Rick H-Y; Wilkinson, Timothy D

    2009-12-20

    Computer generated holography is an extremely demanding and complex task when it comes to providing realistic reconstructions with full parallax, occlusion, and shadowing. We present an algorithm designed for data-parallel computing on modern graphics processing units to alleviate the computational burden. We apply Gaussian interpolation to create a continuous surface representation from discrete input object points. The algorithm maintains a potential occluder list for each individual hologram plane sample to keep the number of visibility tests to a minimum. We experimented with two approximations that simplify and accelerate occlusion computation. It is observed that letting several neighboring hologram plane samples share visibility information on object points leads to significantly faster computation without causing noticeable artifacts in the reconstructed images. Computing a reduced sample set via nonuniform sampling is also found to be an effective acceleration technique.

  13. Calcaneal osteotomy preoperative planning system with 3D full-sized computer-assisted technology.

    PubMed

    Chou, Yi-Jiun; Sun, Shuh-Ping; Liu, Hsin-Hua

    2011-10-01

    In this study, we developed a CT-based computer-assisted pre-operative planning and simulating system for the calcaneal osteotomy by integrating different software's function. This system uses the full-scaled 3D reverse engineering technique in designing and developing preoperative planning modules for the calcaneal osteotomy surgery. The planning system presents a real-sized three-dimensional image of the calcaneus, and provides detailed interior measurements of the calcaneus from various cutting planes. This study applied computer-assisted technology to integrate different software's function to a surgical planning system. These functions include 3-D image model capturing, cutting, moving, rotating and measurement for relevant foot anatomy, and can be integrated as the user's function. Furthermore, the system is computer-based and computer-assisted technology. Surgeons can utilize it as part of preoperative planning to develop efficient operative procedures. This system also has a database that can be updated and extended and will provide the clinical cases to different users for experienced based learning.

  14. Exploiting Graphics Processing Units for Computational Biology and Bioinformatics

    PubMed Central

    Payne, Joshua L.; Sinnott-Armstrong, Nicholas A.; Moore, Jason H.

    2010-01-01

    Advances in the video gaming industry have led to the production of low-cost, high-performance graphics processing units (GPUs) that possess more memory bandwidth and computational capability than central processing units (CPUs), the standard workhorses of scientific computing. With the recent release of general-purpose GPUs and Nvidia's GPU programming language, CUDA, graphics engines are being adopted widely in scientific computing applications, particularly in the fields of computational biology and bioinformatics. The goal of this article is to concisely present an introduction to GPU hardware and programming, aimed at the computational biologist or bioinformaticist. To this end, we discuss the primary differences between GPU and CPU architecture, introduce the basics of the CUDA programming language, and discuss important CUDA programming practices, such as the proper use of coalesced reads, data types, and memory hierarchies. We highlight each of these topics in the context of computing the all-pairs distance between instances in a dataset, a common procedure in numerous disciplines of scientific computing. We conclude with a runtime analysis of the GPU and CPU implementations of the all-pairs distance calculation. We show our final GPU implementation to outperform the CPU implementation by a factor of 1700. PMID:20658333

  15. Exploiting graphics processing units for computational biology and bioinformatics.

    PubMed

    Payne, Joshua L; Sinnott-Armstrong, Nicholas A; Moore, Jason H

    2010-09-01

    Advances in the video gaming industry have led to the production of low-cost, high-performance graphics processing units (GPUs) that possess more memory bandwidth and computational capability than central processing units (CPUs), the standard workhorses of scientific computing. With the recent release of generalpurpose GPUs and NVIDIA's GPU programming language, CUDA, graphics engines are being adopted widely in scientific computing applications, particularly in the fields of computational biology and bioinformatics. The goal of this article is to concisely present an introduction to GPU hardware and programming, aimed at the computational biologist or bioinformaticist. To this end, we discuss the primary differences between GPU and CPU architecture, introduce the basics of the CUDA programming language, and discuss important CUDA programming practices, such as the proper use of coalesced reads, data types, and memory hierarchies. We highlight each of these topics in the context of computing the all-pairs distance between instances in a dataset, a common procedure in numerous disciplines of scientific computing. We conclude with a runtime analysis of the GPU and CPU implementations of the all-pairs distance calculation. We show our final GPU implementation to outperform the CPU implementation by a factor of 1700.

  16. A novel iterative computation algorithm for Kinoform of 3D object

    NASA Astrophysics Data System (ADS)

    Jiang, Xiao-yu; Chuang, Pei; Wang, Xi; Zong, Yantao

    2012-11-01

    A novel method for computing kinoform of 3D object based on traditional iterate Fourier transform algorithm(IFTA) is proposed in this paper. Kinoform is a special kind of computer-generated holograms (CGH) which has very high diffraction efficiency since it only modulates the phase of illuminated light and doesn't have cross-interference from conjugate image. The traditional IFTA arithmetic assumes that reconstruction image is in infinity area(Fraunhofer diffraction region), and ignores the deepness of 3D object ,so it can only calculate two-dimensional kinoform. The proposed algorithm in this paper divides three-dimensional object into several object planes in deepness and treat every object plane as a target image then iterate computation is carried out between one input plane(kinoform) and multi-output planes(reconstruction images) .A space phase factor is added into iterate process to represent depth characters of 3D object, then reconstruction images is in Fresnel diffraction region. Optics reconstructed experiment of kinoform computed by this method is realized based on Liquid Crystals on Silicon (LCoS) Spatial Light Modulator(SLM). Mean Square Error(MSE) and Structure Similarity(SSIM) between original and reconstruction image is used to evaluate this method. The experimental result shows that this algorithm speed is fast and the result kinoform can reconstruct the object in different plane with high precision under the illumination of plane wave. The reconstruction images provide space sense of three-dimensional visual effect. At last, the influence of space and shelter between different object planes to reconstruction image is also discussed in the experiment.

  17. 3D computational reconstruction of tissues with hollow spherical morphologies using single-cell gene expression data.

    PubMed

    Durruthy-Durruthy, Robert; Gottlieb, Assaf; Heller, Stefan

    2015-03-01

    Single-cell gene expression analysis has contributed to a better understanding of the transcriptional heterogeneity in a variety of model systems, including those used in research in developmental, cancer and stem cell biology. Nowadays, technological advances facilitate the generation of large gene expression data sets in high-throughput format. Strategies are needed to pertinently visualize this information in a tissue structure-related context, so as to improve data analysis and aid the drawing of meaningful conclusions. Here we describe an approach that uses spatial properties of the tissue source to enable the reconstruction of hollow sphere-shaped tissues and organs from single-cell gene expression data in 3D space. To demonstrate our method, we used cells of the mouse otocyst and the renal vesicle as examples. This protocol presents a straightforward computational expression analysis workflow, and it is implemented on the MATLAB and R statistical computing and graphics software platforms. Hands-on time for typical experiments can be <1 h using a standard desktop PC or Mac.

  18. Graphical Input Methodology for Computer Aided Analysis of Control Systems.

    DTIC Science & Technology

    1979-12-01

    Control Data Corporation (CDC) CYBER series computer (Ref 4,8). It is designed to run as an INTERCOM job under the NOS/BE operating system (Ref 1,3,5,9...19147-3, Contract- 5- -7. Seattle, Washington, Boeing Areospace Company, 1979. 8. Control Data Corporation . Fortran Extended Version 4 Reference...Manual. Pub. No. 614978%0, Revsion D. Sunnyvale,-California: Publications and Graphics n Division, 1978. 9. Control Data Corporation . INTERCOM Version 4

  19. Computational Analysis of the Transonic Dynamics Tunnel Using FUN3D

    NASA Technical Reports Server (NTRS)

    Chwalowski, Pawel; Quon, Eliot; Brynildsen, Scott E.

    2016-01-01

    This paper presents results from an exploratory two-year effort of applying Computational Fluid Dynamics (CFD) to analyze the empty-tunnel flow in the NASA Langley Research Center Transonic Dynamics Tunnel (TDT). The TDT is a continuous-flow, closed circuit, 16- x 16-foot slotted-test-section wind tunnel, with capabilities to use air or heavy gas as a working fluid. In this study, experimental data acquired in the empty tunnel using the R-134a test medium was used to calibrate the computational data. The experimental calibration data includes wall pressures, boundary-layer profiles, and the tunnel centerline Mach number profiles. Subsonic and supersonic flow regimes were considered, focusing on Mach 0.5, 0.7 and Mach 1.1 in the TDT test section. This study discusses the computational domain, boundary conditions, and initial conditions selected and the resulting steady-state analyses using NASA's FUN3D CFD software.

  20. Computational Analysis of the Transonic Dynamics Tunnel Using FUN3D

    SciTech Connect

    Chwalowski, Pawel; Quon, Eliot; Brynildsen, Scott E.

    2016-01-04

    This paper presents results from an explanatory two-year effort of applying Computational Fluid Dynamics (CFD) to analyze the empty-tunnel flow in the NASA Langley Research Center Transonic Dynamics Tunnel (TDT). The TDT is a continuous-flow, closed circuit, 16- x 16-foot slotted-test-section wind tunnel, with capabilities to use air or heavy gas as a working fluid. In this study, experimental data acquired in the empty tunnel using the R-134a test medium was used to calibrate the computational data. The experimental calibration data includes wall pressures, boundary-layer profiles, and the tunnel centerline Mach number profiles. Subsonic and supersonic flow regimes were considered, focusing on Mach 0.5, 0.7 and Mach 1.1 in the TDT test section. This study discusses the computational domain, boundary conditions, and initial conditions selected in the resulting steady-state analyses using NASA's FUN3D CFD software.

  1. Development of computer program NAS3D using Vector processing for geometric nonlinear analysis of structures

    NASA Technical Reports Server (NTRS)

    Mangalgiri, P. D.; Prabhakaran, R.

    1986-01-01

    An algorithm for vectorized computation of stiffness matrices of an 8 noded isoparametric hexahedron element for geometric nonlinear analysis was developed. This was used in conjunction with the earlier 2-D program GAMNAS to develop the new program NAS3D for geometric nonlinear analysis. A conventional, modified Newton-Raphson process is used for the nonlinear analysis. New schemes for the computation of stiffness and strain energy release rates is presented. The organization the program is explained and some results on four sample problems are given. The study of CPU times showed that savings by a factor of 11 to 13 were achieved when vectorized computation was used for the stiffness instead of the conventional scalar one. Finally, the scheme of inputting data is explained.

  2. Pore detection in Computed Tomography (CT) soil 3D images using singularity map analysis

    NASA Astrophysics Data System (ADS)

    Sotoca, Juan J. Martin; Tarquis, Ana M.; Saa Requejo, Antonio; Grau, Juan B.

    2016-04-01

    X-ray Computed Tomography (CT) images have significantly helped the study of the internal soil structure. This technique has two main advantages: 1) it is a non-invasive technique, i.e., it doesńt modify the internal soil structure, and 2) it provides a good resolution. The major disadvantage is that these images are sometimes low-contrast in the solid/pore interface. One of the main problems in analyzing soil structure through CT images is to segment them in solid/pore space. To do so, we have different segmentation techniques at our disposal that are mainly based on thresholding methods in which global or local thresholds are calculated to separate pore space from solid space. The aim of this presentation is to develop the fractal approach to soil structure using "singularity maps" and the "Concentration-Area (CA) method". We will establish an analogy between mineralization processes in ore deposits and morphogenesis processes in soils. Resulting from this analogy a new 3D segmentation method is proposed, the "3D Singularity-CA" method. A comparison with traditional 3D segmentation methods will be performed to show the main differences among them.

  3. First direct 3D visualisation of microstructural evolutions during sintering through X-ray computed microtomography

    SciTech Connect

    Bernard, Dominique . E-mail: bernard@icmcb.u-bordeaux.fr; Gendron, Damien; Heintz, Jean-Marc; Bordere, Sylvie; Etourneau, Jean

    2005-01-03

    X-ray computed microtomography (XCMT) has been applied to ceramic samples of different materials to visualise, for the first time at this scale, real 3D microstructural evolutions during sintering. Using this technique, it has been possible to follow the whole sintering process of the same grains set. Two materials have been studied; a glass powder heat treated at 700 deg. C and a crystallised lithium borate (Li{sub 6}Gd(BO{sub 3}){sub 3}) powder heat treated at 720 deg. C. XCMT measurements have been done after different sintering times. For each material, a sub-volume was individualised and localised on the successive recordings and its 3D images numerically reconstructed. Description of the three-dimensional microstructures evolution is proposed. From the 3D experimental data, quantitative evolutions of parameters such as porosity and neck size are presented for the glass sample. Possibilities offered by this technique to study complex sintering processes, as for lithium borate, are illustrated.

  4. 3D cephalometric analysis obtained from computed tomography. Review of the literature

    PubMed Central

    Rossini, Giulia; Cavallini, Costanza; Cassetta, Michele; Barbato, Ersilia

    2012-01-01

    Summary Introduction The aim of this systematic review is to estimate accuracy and reproducibility of craniometric measurements and reliability of landmarks identified with computed tomography (CT) techniques in 3D cephalometric analysis. Methods Computerized and manual searches were conducted up to 2011 for studies that addressed these objectives. The selection criteria were: (1) the use of human specimen; (2) the comparison between 2D and 3D cephalometric analysis; (3) the assessment of accuracy, reproducibility of measurements and reliability of landmark identification with CT images compared with two-dimensional conventional radiographs. The Cochrane Handbook for Systematic Reviews of Interventions was used as the guideline for this article. Results Twenty-seven articles met the inclusion criteria. Most of them demonstrated high measurements accuracy and reproducibility, and landmarks reliability, but their cephalometric analysis methodology varied widely. Conclusion These differencies among the studies in making measurements don’t permit a direct comparison between them. The future developments in the knowledge of these techniques should provide a standardized method to conduct the 3D CT cephalometric analysis. PMID:22545187

  5. New solutions for industrial inspection based on 3D computer tomography

    NASA Astrophysics Data System (ADS)

    Kroll, Julia; Effenberger, Ira; Verl, Alexander

    2008-04-01

    In recent years the requirements of industrial applications relating to image processing have significantly increased. According to fast and modern production processes and optimized manufacturing of high quality products, new ways of image acquisition and analysis are needed. Here the industrial computer tomography (CT) as a non-destructive technology for 3D data generation meets this challenge by offering the possibility of complete inspection of complex industrial parts with all outer and inner geometric features. Consequently CT technology is well suited for different kinds of industrial image-based applications in the field of quality assurance like material testing or first article inspection. Moreover surface reconstruction and reverse engineering applications will benefit from CT. In this paper our new methods for efficient 3D CT-image processing are presented. This includes improved solutions for 3D surface reconstruction, innovative approaches of CAD-based segmentation in the CT volume data and the automatic geometric feature detection in complex parts. However the aspect of accuracy is essential in the field of metrology. In order to enhance precision the CT sensor can be combined with other, more accurate sensor systems generating measure points for CT data correction. All algorithms are applied to real data sets in order to demonstrate our tools.

  6. Registration of 3D ultrasound computer tomography and MRI for evaluation of tissue correspondences

    NASA Astrophysics Data System (ADS)

    Hopp, T.; Dapp, R.; Zapf, M.; Kretzek, E.; Gemmeke, H.; Ruiter, N. V.

    2015-03-01

    3D Ultrasound Computer Tomography (USCT) is a new imaging method for breast cancer diagnosis. In the current state of development it is essential to correlate USCT with a known imaging modality like MRI to evaluate how different tissue types are depicted. Due to different imaging conditions, e.g. with the breast subject to buoyancy in USCT, a direct correlation is demanding. We present a 3D image registration method to reduce positioning differences and allow direct side-by-side comparison of USCT and MRI volumes. It is based on a two-step approach including a buoyancy simulation with a biomechanical model and free form deformations using cubic B-Splines for a surface refinement. Simulation parameters are optimized patient-specifically in a simulated annealing scheme. The method was evaluated with in-vivo datasets resulting in an average registration error below 5mm. Correlating tissue structures can thereby be located in the same or nearby slices in both modalities and three-dimensional non-linear deformations due to the buoyancy are reduced. Image fusion of MRI volumes and USCT sound speed volumes was performed for intuitive display. By applying the registration to data of our first in-vivo study with the KIT 3D USCT, we could correlate several tissue structures in MRI and USCT images and learn how connective tissue, carcinomas and breast implants observed in the MRI are depicted in the USCT imaging modes.

  7. Computational-optical microscopy for 3D biological imaging beyond the diffraction limit

    NASA Astrophysics Data System (ADS)

    Grover, Ginni

    In recent years, super-resolution imaging has become an important fluorescent microscopy tool. It has enabled imaging of structures smaller than the optical diffraction limit with resolution less than 50 nm. Extension to high-resolution volume imaging has been achieved by integration with various optical techniques. In this thesis, development of a fluorescent microscope to enable high resolution, extended depth, three dimensional (3D) imaging is discussed; which is achieved by integration of computational methods with optical systems. In the first part of the thesis, point spread function (PSF) engineering for volume imaging is discussed. A class of PSFs, referred to as double-helix (DH) PSFs, is generated. The PSFs exhibit two focused spots in the image plane which rotate about the optical axis, encoding depth in rotation of the image. These PSFs extend the depth-of-field up to a factor of ˜5. Precision performance of the DH-PSFs, based on an information theoretical analysis, is compared with other 3D methods with conclusion that the DH-PSFs provide the best precision and the longest depth-of-field. Out of various possible DH-PSFs, a suitable PSF is obtained for super-resolution microscopy. The DH-PSFs are implemented in imaging systems, such as a microscope, with a special phase modulation at the pupil plane. Surface-relief elements which are polarization-insensitive and ˜90% light efficient are developed for phase modulation. The photon-efficient DH-PSF microscopes thus developed are used, along with optimal position estimation algorithms, for tracking and super-resolution imaging in 3D. Imaging at depths-of-field of up to 2.5 microm is achieved without focus scanning. Microtubules were imaged with 3D resolution of (6, 9, 39) nm, which is in close agreement with the theoretical limit. A quantitative study of co-localization of two proteins in volume was conducted in live bacteria. In the last part of the thesis practical aspects of the DH-PSF microscope are

  8. Multigrid Computations of 3-D Incompressible Internal and External Viscous Rotating Flows

    NASA Technical Reports Server (NTRS)

    Sheng, Chunhua; Taylor, Lafayette K.; Chen, Jen-Ping; Jiang, Min-Yee; Whitfield, David L.

    1996-01-01

    This report presents multigrid methods for solving the 3-D incompressible viscous rotating flows in a NASA low-speed centrifugal compressor and a marine propeller 4119. Numerical formulations are given in both the rotating reference frame and the absolute frame. Comparisons are made for the accuracy, efficiency, and robustness between the steady-state scheme and the time-accurate scheme for simulating viscous rotating flows for complex internal and external flow applications. Prospects for further increase in efficiency and accuracy of unsteady time-accurate computations are discussed.

  9. High-performance computational and geostatistical experiments for testing the capabilities of 3-d electrical tomography

    SciTech Connect

    Carle, S. F.; Daily, W. D.; Newmark, R. L.; Ramirez, A.; Tompson, A.

    1999-01-19

    This project explores the feasibility of combining geologic insight, geostatistics, and high-performance computing to analyze the capabilities of 3-D electrical resistance tomography (ERT). Geostatistical methods are used to characterize the spatial variability of geologic facies that control sub-surface variability of permeability and electrical resistivity Synthetic ERT data sets are generated from geostatistical realizations of alluvial facies architecture. The synthetic data sets enable comparison of the "truth" to inversion results, quantification of the ability to detect particular facies at particular locations, and sensitivity studies on inversion parameters

  10. Computing 3-D steady supersonic flow via a new Lagrangian approach

    NASA Technical Reports Server (NTRS)

    Loh, C. Y.; Liou, M.-S.

    1993-01-01

    The new Lagrangian method introduced by Loh and Hui (1990) is extended for 3-D steady supersonic flow computation. Details of the conservation form, the implementation of the local Riemann solver, and the Godunov and the high resolution TVD schemes are presented. The new approach is robust yet accurate, capable of handling complicated geometry and reactions between discontinuous waves. It keeps all the advantages claimed in the 2-D method of Loh and Hui, e.g., crisp resolution for a slip surface (contact discontinuity) and automatic grid generation along the stream.

  11. Computing 3-D steady supersonic flow via a new Lagrangian approach

    NASA Technical Reports Server (NTRS)

    Loh, C. Y.; Liou, M.-S.

    1993-01-01

    The new Lagrangian method introduced by Loh and Hui (1990) is extended for 3-D steady supersonic flow computation. Details of the conservation form, the implementation of the local Riemann solver, and the Godunov and the high resolution TVD schemes are presented. The new approach is robust yet accurate, capable of handling complicated geometry and reactions between discontinuous waves. It keeps all the advantages claimed in the 2-D method of Loh and Hui, e.g., crisp resolution for a slip surface (contact discontinuity) and automatic grid generation along the stream.

  12. Advanced computer graphic techniques for laser range finder (LRF) simulation

    NASA Astrophysics Data System (ADS)

    Bedkowski, Janusz; Jankowski, Stanislaw

    2008-11-01

    This paper show an advanced computer graphic techniques for laser range finder (LRF) simulation. The LRF is the common sensor for unmanned ground vehicle, autonomous mobile robot and security applications. The cost of the measurement system is extremely high, therefore the simulation tool is designed. The simulation gives an opportunity to execute algorithm such as the obstacle avoidance[1], slam for robot localization[2], detection of vegetation and water obstacles in surroundings of the robot chassis[3], LRF measurement in crowd of people[1]. The Axis Aligned Bounding Box (AABB) and alternative technique based on CUDA (NVIDIA Compute Unified Device Architecture) is presented.

  13. Reliability of clinically relevant 3D foot bone angles from quantitative computed tomography

    PubMed Central

    2013-01-01

    Background Surgical treatment and clinical management of foot pathology requires accurate, reliable assessment of foot deformities. Foot and ankle deformities are multi-planar and therefore difficult to quantify by standard radiographs. Three-dimensional (3D) imaging modalities have been used to define bone orientations using inertial axes based on bone shape, but these inertial axes can fail to mimic established bone angles used in orthopaedics and clinical biomechanics. To provide improved clinical relevance of 3D bone angles, we developed techniques to define bone axes using landmarks on quantitative computed tomography (QCT) bone surface meshes. We aimed to assess measurement precision of landmark-based, 3D bone-to-bone orientations of hind foot and lesser tarsal bones for expert raters and a template-based automated method. Methods Two raters completed two repetitions each for twenty feet (10 right, 10 left), placing anatomic landmarks on the surfaces of calcaneus, talus, cuboid, and navicular. Landmarks were also recorded using the automated, template-based method. For each method, 3D bone axes were computed from landmark positions, and Cardan sequences produced sagittal, frontal, and transverse plane angles of bone-to-bone orientations. Angular reliability was assessed using intraclass correlation coefficients (ICCs) and the root mean square standard deviation (RMS-SD) for intra-rater and inter-rater precision, and rater versus automated agreement. Results Intra- and inter-rater ICCs were generally high (≥ 0.80), and the ICCs for each rater compared to the automated method were similarly high. RMS-SD intra-rater precision ranged from 1.4 to 3.6° and 2.4 to 6.1°, respectively, for the two raters, which compares favorably to uni-planar radiographic precision. Greatest variability was in Navicular: Talus sagittal plane angle and Cuboid: Calcaneus frontal plane angle. Precision of the automated, atlas-based template method versus the raters was comparable to

  14. Efficient 3D nonlinear warping of computed tomography: two high-performance implementations using OpenGL

    NASA Astrophysics Data System (ADS)

    Levin, David; Dey, Damini; Slomka, Piotr

    2005-04-01

    We have implemented two hardware accelerated Thin Plate Spline (TPS) warping algorithms. The first algorithm is a hardware-software approach (HW-TPS) that uses OpenGL Vertex Shaders to perform a grid warp. The second is a Graphics Processor based approach (GPU-TPS) that uses the OpenGL Shading Language to perform all warping calculations on the GPU. Comparison with a software TPS algorithm was used to gauge the speed and quality of both hardware algorithms. Quality was analyzed visually and using the Sum of Absolute Difference (SAD) similarity metric. Warping was performed using 92 user-defined displacement vectors for 512x512x173 serial lung CT studies, matching normal-breathing and deep-inspiration scans. On a Xeon 2.2 Ghz machine with an ATI Radeon 9800XT GPU the GPU-TPS required 26.1 seconds to perform a per-voxel warp compared to 148.2 seconds for the software algorithm. The HW-TPS needed 1.63 seconds to warp the same study while the GPU-TPS required 1.94 seconds and the software grid transform required 22.8 seconds. The SAD values calculated between the outputs of each algorithm and the target CT volume were 15.2%, 15.4% and 15.5% for the HW-TPS, GPU-TPS and both software algorithms respectively. The computing power of ubiquitous 3D graphics cards can be exploited in medical image processing to provide order of magnitude acceleration of nonlinear warping algorithms without sacrificing output quality.

  15. Reflective Metasurfaces for Incoherent Light To Bring Computer Graphics Tricks to Optical Systems.

    PubMed

    Minovich, Alexander E; Peter, Manuel; Bleckmann, Felix; Becker, Manuel; Linden, Stefan; Zayats, Anatoly V

    2017-07-12

    The normal mapping technique is widely used in computer graphics to visualize three-dimensional (3D) objects displayed on a flat screen. Taking advantage of optical properties of metasurfaces, which provide a highly efficient approach for manipulation of incident light wavefront, we have designed a metasurface to implement diffuse reflection and used the concept of normal mapping to control its scattering properties. As a proof of principle, we have fabricated and characterized a flat diffuse metasurface imitating lighting and shading effects of a 3D cube. The 3D image is displayed directly on the illuminated metasurface and it is brighter than a standard white paper by up to 2.4 times. The designed structure performs equally well under coherent and incoherent illumination. The normal mapping approach based on metasurfaces can complement traditional optical engineering methods of surface profiling and gradient refractive index engineering in the design of 3D security features, high-performance planar optical diffusers, novel optical elements, and displays.

  16. Form in the Natural Environment: Fractal Computer Graphics and Wassily Kandinsky.

    ERIC Educational Resources Information Center

    Geake, John; Porter, Jim

    1992-01-01

    Reports on study of use of fractal geometry in a computer graphics program to improve the perception of intermediate grade level students in their paintings. Finds that students are more likely to use changing shapes and colors after viewing slides of fractal computer graphics. Concludes that fractal computer graphics would make highly engaging…

  17. Form in the Natural Environment: Fractal Computer Graphics and Wassily Kandinsky.

    ERIC Educational Resources Information Center

    Geake, John; Porter, Jim

    1992-01-01

    Reports on study of use of fractal geometry in a computer graphics program to improve the perception of intermediate grade level students in their paintings. Finds that students are more likely to use changing shapes and colors after viewing slides of fractal computer graphics. Concludes that fractal computer graphics would make highly engaging…

  18. 3D virtual human atria: A computational platform for studying clinical atrial fibrillation

    PubMed Central

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

    2011-01-01

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

  19. 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

  20. Quick, Accurate, Smart: 3D Computer Vision Technology Helps Assessing Confined Animals’ Behaviour

    PubMed Central

    Calderara, Simone; Pistocchi, Simone; Cucchiara, Rita; Podaliri-Vulpiani, Michele; Messori, Stefano; Ferri, Nicola

    2016-01-01

    Mankind directly controls the environment and lifestyles of several domestic species for purposes ranging from production and research to conservation and companionship. These environments and lifestyles may not offer these animals the best quality of life. Behaviour is a direct reflection of how the animal is coping with its environment. Behavioural indicators are thus among the preferred parameters to assess welfare. However, behavioural recording (usually from video) can be very time consuming and the accuracy and reliability of the output rely on the experience and background of the observers. The outburst of new video technology and computer image processing gives the basis for promising solutions. In this pilot study, we present a new prototype software able to automatically infer the behaviour of dogs housed in kennels from 3D visual data and through structured machine learning frameworks. Depth information acquired through 3D features, body part detection and training are the key elements that allow the machine to recognise postures, trajectories inside the kennel and patterns of movement that can be later labelled at convenience. The main innovation of the software is its ability to automatically cluster frequently observed temporal patterns of movement without any pre-set ethogram. Conversely, when common patterns are defined through training, a deviation from normal behaviour in time or between individuals could be assessed. The software accuracy in correctly detecting the dogs’ behaviour was checked through a validation process. An automatic behaviour recognition system, independent from human subjectivity, could add scientific knowledge on animals’ quality of life in confinement as well as saving time and resources. This 3D framework was designed to be invariant to the dog’s shape and size and could be extended to farm, laboratory and zoo quadrupeds in artificial housing. The computer vision technique applied to this software is innovative in non

  1. Quick, Accurate, Smart: 3D Computer Vision Technology Helps Assessing Confined Animals' Behaviour.

    PubMed

    Barnard, Shanis; Calderara, Simone; Pistocchi, Simone; Cucchiara, Rita; Podaliri-Vulpiani, Michele; Messori, Stefano; Ferri, Nicola

    2016-01-01

    Mankind directly controls the environment and lifestyles of several domestic species for purposes ranging from production and research to conservation and companionship. These environments and lifestyles may not offer these animals the best quality of life. Behaviour is a direct reflection of how the animal is coping with its environment. Behavioural indicators are thus among the preferred parameters to assess welfare. However, behavioural recording (usually from video) can be very time consuming and the accuracy and reliability of the output rely on the experience and background of the observers. The outburst of new video technology and computer image processing gives the basis for promising solutions. In this pilot study, we present a new prototype software able to automatically infer the behaviour of dogs housed in kennels from 3D visual data and through structured machine learning frameworks. Depth information acquired through 3D features, body part detection and training are the key elements that allow the machine to recognise postures, trajectories inside the kennel and patterns of movement that can be later labelled at convenience. The main innovation of the software is its ability to automatically cluster frequently observed temporal patterns of movement without any pre-set ethogram. Conversely, when common patterns are defined through training, a deviation from normal behaviour in time or between individuals could be assessed. The software accuracy in correctly detecting the dogs' behaviour was checked through a validation process. An automatic behaviour recognition system, independent from human subjectivity, could add scientific knowledge on animals' quality of life in confinement as well as saving time and resources. This 3D framework was designed to be invariant to the dog's shape and size and could be extended to farm, laboratory and zoo quadrupeds in artificial housing. The computer vision technique applied to this software is innovative in non

  2. 3D modeling method for computer animate based on modified weak structured light method

    NASA Astrophysics Data System (ADS)

    Xiong, Hanwei; Pan, Ming; Zhang, Xiangwei

    2010-11-01

    A simple and affordable 3D scanner is designed in this paper. Three-dimensional digital models are playing an increasingly important role in many fields, such as computer animate, industrial design, artistic design and heritage conservation. For many complex shapes, optical measurement systems are indispensable to acquiring the 3D information. In the field of computer animate, such an optical measurement device is too expensive to be widely adopted, and on the other hand, the precision is not as critical a factor in that situation. In this paper, a new cheap 3D measurement system is implemented based on modified weak structured light, using only a video camera, a light source and a straight stick rotating on a fixed axis. For an ordinary weak structured light configuration, one or two reference planes are required, and the shadows on these planes must be tracked in the scanning process, which destroy the convenience of this method. In the modified system, reference planes are unnecessary, and size range of the scanned objects is expanded widely. A new calibration procedure is also realized for the proposed method, and points cloud is obtained by analyzing the shadow strips on the object. A two-stage ICP algorithm is used to merge the points cloud from different viewpoints to get a full description of the object, and after a series of operations, a NURBS surface model is generated in the end. A complex toy bear is used to verify the efficiency of the method, and errors range from 0.7783mm to 1.4326mm comparing with the ground truth measurement.

  3. "Let's get physical": advantages of a physical model over 3D computer models and textbooks in learning imaging anatomy.

    PubMed

    Preece, Daniel; Williams, Sarah B; Lam, Richard; Weller, Renate

    2013-01-01

    Three-dimensional (3D) information plays an important part in medical and veterinary education. Appreciating complex 3D spatial relationships requires a strong foundational understanding of anatomy and mental 3D visualization skills. Novel learning resources have been introduced to anatomy training to achieve this. Objective evaluation of their comparative efficacies remains scarce in the literature. This study developed and evaluated the use of a physical model in demonstrating the complex spatial relationships of the equine foot. It was hypothesized that the newly developed physical model would be more effective for students to learn magnetic resonance imaging (MRI) anatomy of the foot than textbooks or computer-based 3D models. Third year veterinary medicine students were randomly assigned to one of three teaching aid groups (physical model; textbooks; 3D computer model). The comparative efficacies of the three teaching aids were assessed through students' abilities to identify anatomical structures on MR images. Overall mean MRI assessment scores were significantly higher in students utilizing the physical model (86.39%) compared with students using textbooks (62.61%) and the 3D computer model (63.68%) (P < 0.001), with no significant difference between the textbook and 3D computer model groups (P = 0.685). Student feedback was also more positive in the physical model group compared with both the textbook and 3D computer model groups. Our results suggest that physical models may hold a significant advantage over alternative learning resources in enhancing visuospatial and 3D understanding of complex anatomical architecture, and that 3D computer models have significant limitations with regards to 3D learning. © 2013 American Association of Anatomists.

  4. Interactive Computer Graphics for Performance-Structure-Oriented CAI. Technical Report No. 73.

    ERIC Educational Resources Information Center

    Rigney, Joseph W.; And Others

    Two different uses of interactive graphics in computer-assisted instruction are described. Interactive graphics may be used as substitutes for physical devices and operations. An example is simulation of operating on man/machine interfaces, substituting interactive graphics for controls, indicators, and indications. Interactive graphics may also…

  5. FaceWarehouse: a 3D facial expression database for visual computing.

    PubMed

    Cao, Chen; Weng, Yanlin; Zhou, Shun; Tong, Yiying; Zhou, Kun

    2014-03-01

    We present FaceWarehouse, a database of 3D facial expressions for visual computing applications. We use Kinect, an off-the-shelf RGBD camera, to capture 150 individuals aged 7-80 from various ethnic backgrounds. For each person, we captured the RGBD data of her different expressions, including the neutral expression and 19 other expressions such as mouth-opening, smile, kiss, etc. For every RGBD raw data record, a set of facial feature points on the color image such as eye corners, mouth contour, and the nose tip are automatically localized, and manually adjusted if better accuracy is required. We then deform a template facial mesh to fit the depth data as closely as possible while matching the feature points on the color image to their corresponding points on the mesh. Starting from these fitted face meshes, we construct a set of individual-specific expression blendshapes for each person. These meshes with consistent topology are assembled as a rank-3 tensor to build a bilinear face model with two attributes: identity and expression. Compared with previous 3D facial databases, for every person in our database, there is a much richer matching collection of expressions, enabling depiction of most human facial actions. We demonstrate the potential of FaceWarehouse for visual computing with four applications: facial image manipulation, face component transfer, real-time performance-based facial image animation, and facial animation retargeting from video to image.

  6. High performance computing approaches for 3D reconstruction of complex biological specimens.

    PubMed

    da Silva, M Laura; Roca-Piera, Javier; Fernández, José-Jesús

    2010-01-01

    Knowledge of the structure of specimens is crucial to determine the role that they play in cellular and molecular biology. To yield the three-dimensional (3D) reconstruction by means of tomographic reconstruction algorithms, we need the use of large projection images and high processing time. Therefore, we propose the use of the high performance computing (HPC) to cope with the huge computational demands of this problem. We have implemented a HPC strategy where the distribution of tasks follows the master-slave paradigm. The master processor distributes a slab of slices, a piece of the final 3D structure to reconstruct, among the slave processors and receives reconstructed slices of the volume. We have evaluated the performance of our HPC approach using different sizes of the slab. We have observed that it is possible to find out an optimal size of the slab for the number of processor used that minimize communications time while maintaining a reasonable grain of parallelism to be exploited by the set of processors.

  7. Planned development of a 3D computer based on free-space optical interconnects

    NASA Astrophysics Data System (ADS)

    Neff, John A.; Guarino, David R.

    1994-05-01

    Free-space optical interconnection has the potential to provide upwards of a million data channels between planes of electronic circuits. This may result in the planar board and backplane structures of today giving away to 3-D stacks of wafers or multi-chip modules interconnected via channels running perpendicular to the processor planes, thereby eliminating much of the packaging overhead. Three-dimensional packaging is very appealing for tightly coupled fine-grained parallel computing where the need for massive numbers of interconnections is severely taxing the capabilities of the planar structures. This paper describes a coordinated effort by four research organizations to demonstrate an operational fine-grained parallel computer that achieves global connectivity through the use of free space optical interconnects.

  8. Applying 3D measurements and computer matching algorithms to two firearm examination proficiency tests.

    PubMed

    Ott, Daniel; Thompson, Robert; Song, Junfeng

    2017-02-01

    In order for a crime laboratory to assess a firearms examiner's training, skills, experience, and aptitude, it is necessary for the examiner to participate in proficiency testing. As computer algorithms for comparisons of pattern evidence become more prevalent, it is of interest to test algorithm performance as well, using these same proficiency examinations. This article demonstrates the use of the Congruent Matching Cell (CMC) algorithm to compare 3D topography measurements of breech face impressions and firing pin impressions from a previously distributed firearms proficiency test. In addition, the algorithm is used to analyze the distribution of many comparisons from a collection of cartridge cases used to construct another recent set of proficiency tests. These results are provided along with visualizations that help to relate the features used in optical comparisons by examiners to the features used by computer comparison algorithms.

  9. A review of automated image understanding within 3D baggage computed tomography security screening.

    PubMed

    Mouton, Andre; Breckon, Toby P

    2015-01-01

    Baggage inspection is the principal safeguard against the transportation of prohibited and potentially dangerous materials at airport security checkpoints. Although traditionally performed by 2D X-ray based scanning, increasingly stringent security regulations have led to a growing demand for more advanced imaging technologies. The role of X-ray Computed Tomography is thus rapidly expanding beyond the traditional materials-based detection of explosives. The development of computer vision and image processing techniques for the automated understanding of 3D baggage-CT imagery is however, complicated by poor image resolutions, image clutter and high levels of noise and artefacts. We discuss the recent and most pertinent advancements and identify topics for future research within the challenging domain of automated image understanding for baggage security screening CT.

  10. A new 3-D integral code for computation of accelerator magnets

    SciTech Connect

    Turner, L.R.; Kettunen, L.

    1991-01-01

    For computing accelerator magnets, integral codes have several advantages over finite element codes; far-field boundaries are treated automatically, and computed field in the bore region satisfy Maxwell's equations exactly. A new integral code employing edge elements rather than nodal elements has overcome the difficulties associated with earlier integral codes. By the use of field integrals (potential differences) as solution variables, the number of unknowns is reduced to one less than the number of nodes. Two examples, a hollow iron sphere and the dipole magnet of Advanced Photon Source injector synchrotron, show the capability of the code. The CPU time requirements are comparable to those of three-dimensional (3-D) finite-element codes. Experiments show that in practice it can realize much of the potential CPU time saving that parallel processing makes possible. 8 refs., 4 figs., 1 tab.

  11. Using Computer-Aided Design Software and 3D Printers to Improve Spatial Visualization

    ERIC Educational Resources Information Center

    Katsio-Loudis, Petros; Jones, Millie

    2015-01-01

    Many articles have been published on the use of 3D printing technology. From prefabricated homes and outdoor structures to human organs, 3D printing technology has found a niche in many fields, but especially education. With the introduction of AutoCAD technical drawing programs and now 3D printing, learners can use 3D printed models to develop…

  12. Using Computer-Aided Design Software and 3D Printers to Improve Spatial Visualization

    ERIC Educational Resources Information Center

    Katsio-Loudis, Petros; Jones, Millie

    2015-01-01

    Many articles have been published on the use of 3D printing technology. From prefabricated homes and outdoor structures to human organs, 3D printing technology has found a niche in many fields, but especially education. With the introduction of AutoCAD technical drawing programs and now 3D printing, learners can use 3D printed models to develop…

  13. Graphics

    ERIC Educational Resources Information Center

    Post, Susan

    1975-01-01

    An art teacher described an elective course in graphics which was designed to enlarge a student's knowledge of value, color, shape within a shape, transparency, line and texture. This course utilized the technique of working a multi-colored print from a single block that was first introduced by Picasso. (Author/RK)

  14. Computer Graphics 2: More of the Best Computer Art and Design.

    ERIC Educational Resources Information Center

    1994

    This collection of computer generated images aims to present media tools and processes, stimulate ideas, and inspire artists and art students working in computer-related design. The images are representative of state-of-the-art editorial, broadcast, packaging, fine arts, and graphic techniques possible through computer generation. Each image is…

  15. Computer Graphics 2: More of the Best Computer Art and Design.

    ERIC Educational Resources Information Center

    1994

    This collection of computer generated images aims to present media tools and processes, stimulate ideas, and inspire artists and art students working in computer-related design. The images are representative of state-of-the-art editorial, broadcast, packaging, fine arts, and graphic techniques possible through computer generation. Each image is…

  16. The Effects of 3D Computer Modelling on Conceptual Change about Seasons and Phases of the Moon

    ERIC Educational Resources Information Center

    Kucukozer, Huseyin

    2008-01-01

    In this study, prospective science teachers' misconceptions about the seasons and the phases of the Moon were determined, and then the effects of 3D computer modelling on their conceptual changes were investigated. The topics were covered in two classes with a total of 76 students using a predict-observe-explain strategy supported by 3D computer…

  17. The Effects of 3D Computer Modelling on Conceptual Change about Seasons and Phases of the Moon

    ERIC Educational Resources Information Center

    Kucukozer, Huseyin

    2008-01-01

    In this study, prospective science teachers' misconceptions about the seasons and the phases of the Moon were determined, and then the effects of 3D computer modelling on their conceptual changes were investigated. The topics were covered in two classes with a total of 76 students using a predict-observe-explain strategy supported by 3D computer…

  18. Computer-Based Tools for Evaluating Graphical User Interfaces

    NASA Technical Reports Server (NTRS)

    Moore, Loretta A.

    1997-01-01

    The user interface is the component of a software system that connects two very complex system: humans and computers. Each of these two systems impose certain requirements on the final product. The user is the judge of the usability and utility of the system; the computer software and hardware are the tools with which the interface is constructed. Mistakes are sometimes made in designing and developing user interfaces because the designers and developers have limited knowledge about human performance (e.g., problem solving, decision making, planning, and reasoning). Even those trained in user interface design make mistakes because they are unable to address all of the known requirements and constraints on design. Evaluation of the user inter-face is therefore a critical phase of the user interface development process. Evaluation should not be considered the final phase of design; but it should be part of an iterative design cycle with the output of evaluation being feed back into design. The goal of this research was to develop a set of computer-based tools for objectively evaluating graphical user interfaces. The research was organized into three phases. The first phase resulted in the development of an embedded evaluation tool which evaluates the usability of a graphical user interface based on a user's performance. An expert system to assist in the design and evaluation of user interfaces based upon rules and guidelines was developed during the second phase. During the final phase of the research an automatic layout tool to be used in the initial design of graphical inter- faces was developed. The research was coordinated with NASA Marshall Space Flight Center's Mission Operations Laboratory's efforts in developing onboard payload display specifications for the Space Station.

  19. Neurosurgical simulation by interactive computer graphics on iPad.

    PubMed

    Maruyama, Keisuke; Kin, Taichi; Saito, Toki; Suematsu, Shinya; Gomyo, Miho; Noguchi, Akio; Nagane, Motoo; Shiokawa, Yoshiaki

    2014-11-01

    Presurgical simulation before complicated neurosurgery is a state-of-the-art technique, and its usefulness has recently become well known. However, simulation requires complex image processing, which hinders its widespread application. We explored handling the results of interactive computer graphics on the iPad tablet, which can easily be controlled anywhere. Data from preneurosurgical simulations from 12 patients (4 men, 8 women) who underwent complex brain surgery were loaded onto an iPad. First, DICOM data were loaded using Amira visualization software to create interactive computer graphics, and ParaView, another free visualization software package, was used to convert the results of the simulation to be loaded using the free iPad software KiwiViewer. The interactive computer graphics created prior to neurosurgery were successfully displayed and smoothly controlled on the iPad in all patients. The number of elements ranged from 3 to 13 (mean 7). The mean original data size was 233 MB, which was reduced to 10.4 MB (4.4% of original size) after image processing by ParaView. This was increased to 46.6 MB (19.9%) after decompression in KiwiViewer. Controlling the magnification, transfer, rotation, and selection of translucence in 10 levels of each element were smoothly and easily performed using one or two fingers. The requisite skill to smoothly control the iPad software was acquired within 1.8 trials on average in 12 medical students and 6 neurosurgical residents. Using an iPad to handle the result of preneurosurgical simulation was extremely useful because it could easily be handled anywhere.

  20. Computational chemistry approach to protein kinase recognition using 3D stochastic van der Waals spectral moments.

    PubMed

    González-Díaz, Humberto; Saíz-Urra, Liane; Molina, Reinaldo; González-Díaz, Yenny; Sánchez-González, Angeles

    2007-04-30

    Three-dimensional (3D) protein structures now frequently lack functional annotations because of the increase in the rate at which chemical structures are solved with respect to experimental knowledge of biological activity. As a result, predicting structure-function relationships for proteins is an active research field in computational chemistry and has implications in medicinal chemistry, biochemistry and proteomics. In previous studies stochastic spectral moments were used to predict protein stability or function (González-Díaz, H. et al. Bioorg Med Chem 2005, 13, 323; Biopolymers 2005, 77, 296). Nevertheless, these moments take into consideration only electrostatic interactions and ignore other important factors such as van der Waals interactions. The present study introduces a new class of 3D structure molecular descriptors for folded proteins named the stochastic van der Waals spectral moments ((o)beta(k)). Among many possible applications, recognition of kinases was selected due to the fact that previous computational chemistry studies in this area have not been reported, despite the widespread distribution of kinases. The best linear model found was Kact = -9.44 degrees beta(0)(c) +10.94 degrees beta(5)(c) -2.40 degrees beta(0)(i) + 2.45 degrees beta(5)(m) + 0.73, where core (c), inner (i) and middle (m) refer to specific spatial protein regions. The model with a high Matthew's regression coefficient (0.79) correctly classified 206 out of 230 proteins (89.6%) including both training and predicting series. An area under the ROC curve of 0.94 differentiates our model from a random classifier. A subsequent principal components analysis of 152 heterogeneous proteins demonstrated that beta(k) codifies information different to other descriptors used in protein computational chemistry studies. Finally, the model recognizes 110 out of 125 kinases (88.0%) in a virtual screening experiment and this can be considered as an additional validation study (these proteins

  1. Graphics processing unit accelerated computation of digital holograms.

    PubMed

    Kang, Hoonjong; Yaraş, Fahri; Onural, Levent

    2009-12-01

    An approximation for fast digital hologram generation is implemented on a central processing unit (CPU), a graphics processing unit (GPU), and a multi-GPU computational platform. The computational performance of the method on each platform is measured and compared. The computational speed on the GPU platform is much faster than on a CPU, and the algorithm could be further accelerated on a multi-GPU platform. In addition, the accuracy of the algorithm for single- and double-precision arithmetic is evaluated. The quality of the reconstruction from the algorithm using single-precision arithmetic is comparable with the quality from the double-precision arithmetic, and thus the implementation using single-precision arithmetic on a multi-GPU platform can be used for holographic video displays.

  2. A brain-computer interface method combined with eye tracking for 3D interaction.

    PubMed

    Lee, Eui Chul; Woo, Jin Cheol; Kim, Jong Hwa; Whang, Mincheol; Park, Kang Ryoung

    2010-07-15

    With the recent increase in the number of three-dimensional (3D) applications, the need for interfaces to these applications has increased. Although the eye tracking method has been widely used as an interaction interface for hand-disabled persons, this approach cannot be used for depth directional navigation. To solve this problem, we propose a new brain computer interface (BCI) method in which the BCI and eye tracking are combined to analyze depth navigation, including selection and two-dimensional (2D) gaze direction, respectively. The proposed method is novel in the following five ways compared to previous works. First, a device to measure both the gaze direction and an electroencephalogram (EEG) pattern is proposed with the sensors needed to measure the EEG attached to a head-mounted eye tracking device. Second, the reliability of the BCI interface is verified by demonstrating that there is no difference between the real and the imaginary movements for the same work in terms of the EEG power spectrum. Third, depth control for the 3D interaction interface is implemented by an imaginary arm reaching movement. Fourth, a selection method is implemented by an imaginary hand grabbing movement. Finally, for the independent operation of gazing and the BCI, a mode selection method is proposed that measures a user's concentration by analyzing the pupil accommodation speed, which is not affected by the operation of gazing and the BCI. According to experimental results, we confirmed the feasibility of the proposed 3D interaction method using eye tracking and a BCI. Copyright 2010 Elsevier B.V. All rights reserved.

  3. STS-49 ASEM activities illustrated with PLAID computer graphics

    NASA Technical Reports Server (NTRS)

    1992-01-01

    STS-49 Endeavour, Orbiter Vehicle (OV) 105, Assembly of Station by Extravehicular Activity (EVA) Methods (ASEM) activities are illustrated with PLAID computer graphics. The multipurpose experiment support structure (MPESS) grappled by the remote manipulator system (RMS) end effector is positioned over OV-105's payload bay (PLB) as extravehicular mobility unit (EMU) suited crewmembers attach MPESS to ASEM truss structure with 'legs'. One astronaut, floating, works near the top of the structure while the second astronaut works at a payload retention latch assembly (PLRA) on the starboard sill. The empty INTELSAT perigee stage cradle structure is seen in the aft PLB.

  4. STS-49 ASEM activities illustrated with PLAID computer graphics

    NASA Technical Reports Server (NTRS)

    1992-01-01

    STS-49 Endeavour, Orbiter Vehicle (OV) 105, Assembly of Station by Extravehicular Activity (EVA) Methods (ASEM) activities are illustrated with PLAID computer graphics. Two extravehicular mobility unit (EMU) suited crewmembers work on multipurpose experiment support structure (MPESS) (with legs attached) grappled by remote manipulator system (RMS) end effector and positioned in the over-the-nose location (above OV-105's crew compartment). This position has been designated as the assembly area for Space Station Freedom (SSF). This procedure will evaluate the ability to use the RMS to position MPESS carrier and EVA crewmembers forward and above the PLB.

  5. Soft computing approach to 3D lung nodule segmentation in CT.

    PubMed

    Badura, P; Pietka, E

    2014-10-01

    This paper presents a novel, multilevel approach to the segmentation of various types of pulmonary nodules in computed tomography studies. It is based on two branches of computational intelligence: the fuzzy connectedness (FC) and the evolutionary computation. First, the image and auxiliary data are prepared for the 3D FC analysis during the first stage of an algorithm - the masks generation. Its main goal is to process some specific types of nodules connected to the pleura or vessels. It consists of some basic image processing operations as well as dedicated routines for the specific cases of nodules. The evolutionary computation is performed on the image and seed points in order to shorten the FC analysis and improve its accuracy. After the FC application, the remaining vessels are removed during the postprocessing stage. The method has been validated using the first dataset of studies acquired and described by the Lung Image Database Consortium (LIDC) and by its latest release - the LIDC-IDRI (Image Database Resource Initiative) database.

  6. Cloud4Psi: cloud computing for 3D protein structure similarity searching.

    PubMed

    Mrozek, Dariusz; Małysiak-Mrozek, Bożena; Kłapciński, Artur

    2014-10-01

    Popular methods for 3D protein structure similarity searching, especially those that generate high-quality alignments such as Combinatorial Extension (CE) and Flexible structure Alignment by Chaining Aligned fragment pairs allowing Twists (FATCAT) are still time consuming. As a consequence, performing similarity searching against large repositories of structural data requires increased computational resources that are not always available. Cloud computing provides huge amounts of computational power that can be provisioned on a pay-as-you-go basis. We have developed the cloud-based system that allows scaling of the similarity searching process vertically and horizontally. Cloud4Psi (Cloud for Protein Similarity) was tested in the Microsoft Azure cloud environment and provided good, almost linearly proportional acceleration when scaled out onto many computational units. Cloud4Psi is available as Software as a Service for testing purposes at: http://cloud4psi.cloudapp.net/. For source code and software availability, please visit the Cloud4Psi project home page at http://zti.polsl.pl/dmrozek/science/cloud4psi.htm. © The Author 2014. Published by Oxford University Press.

  7. Computing Emissions from Active-Region Loops in 3D and High Resolution

    NASA Astrophysics Data System (ADS)

    Mok, Yung; Lionello, R.; Mikic, Z.; Linker, J.

    2009-05-01

    Plasma loops are widely observed in EUV and soft X-ray over active regions, but their thermal properties and formation mechanism have be controversial. In this work, we are able to reproduce some of the loop properties by forward modeling. Using an MDI magnetogram, we constructed a mildly sheared force-free magnetic field based on parameters deduced from observation. The field was computed in unusually high spatial resolution in order to resolve the expected thin coronal loops. Although the magnetogram has fine structures at the photospheric level, the field in the corona is smooth as expected. The field lines have moderately complex connectivity. We then chose a specific heating model and computed the thermal structure in 3D. Although the overall temperature profile has only moderate spatial variations in the corona, the computed line-of-sight integrated EUV emissions show a complex system of thin plasma loops. Initial analysis shows that thermal instability leads to the time variation of the loop brightness. The lack of cross-section expansion is also apparent. The location of the loops and their relationship with the magnetic field will also be discussed. Work supported by HTP of NASA. Computation resources provided by NAS at Ames Research Center, NASA.

  8. Computational time analysis of the numerical solution of 3D electrostatic Poisson's equation

    NASA Astrophysics Data System (ADS)

    Kamboh, Shakeel Ahmed; Labadin, Jane; Rigit, Andrew Ragai Henri; Ling, Tech Chaw; Amur, Khuda Bux; Chaudhary, Muhammad Tayyab

    2015-05-01

    3D Poisson's equation is solved numerically to simulate the electric potential in a prototype design of electrohydrodynamic (EHD) ion-drag micropump. Finite difference method (FDM) is employed to discretize the governing equation. The system of linear equations resulting from FDM is solved iteratively by using the sequential Jacobi (SJ) and sequential Gauss-Seidel (SGS) methods, simulation results are also compared to examine the difference between the results. The main objective was to analyze the computational time required by both the methods with respect to different grid sizes and parallelize the Jacobi method to reduce the computational time. In common, the SGS method is faster than the SJ method but the data parallelism of Jacobi method may produce good speedup over SGS method. In this study, the feasibility of using parallel Jacobi (PJ) method is attempted in relation to SGS method. MATLAB Parallel/Distributed computing environment is used and a parallel code for SJ method is implemented. It was found that for small grid size the SGS method remains dominant over SJ method and PJ method while for large grid size both the sequential methods may take nearly too much processing time to converge. Yet, the PJ method reduces computational time to some extent for large grid sizes.

  9. Efficacy of computer-assisted, 3D motion-capture toothbrushing instruction.

    PubMed

    Kim, Kee-Deog; Jeong, Jin-Sun; Lee, Hae Na; Gu, Yu; Kim, Kyeong-Seop; Lee, Jeong-Whan; Park, Wonse

    2015-07-01

    The objective of this study was to compare the efficacy of computer-assisted TBI using a smart toothbrush (ST) and smart mirror (SM) in plaque control to that of conventional TBI. We evaluated the plaque removal efficacy of a ST comprising a computer-assisted, wirelessly linked, three-dimensional (3D) motion-capture, data-logging, and SM system in TBI. We also evaluated the efficacy of TBI with a ST and SM system by analyzing the reductions of the modified Quigley-Hein plaque index in 60 volunteers. These volunteers were separated randomly into two groups: conventional TBI (control group) and computer-assisted TBI (experimental group). The changes in the plaque indexes were recorded immediately, 1 week, 1 month, and 10 months after TBI. The patterns of decreases in the modified Quigley-Hein plaque indexes were similar in the two groups. Reductions of the plaque indexes of both groups in each time period were observed (P < 0.0001), and the effects of TBI did not differ between the two groups (P = 0.3803). All volunteers were sufficiently motivated in using this new system. The reported new, computer-assisted TBI system might be an alternative option in controlling dental plaque and maintaining oral hygiene. Individuals can be motivated by the new system; meanwhile, comparable effects of controlling dental plaque can be achieved.

  10. Optimization of the aperture and the transducer characteristics of a 3D ultrasound computer tomography system

    NASA Astrophysics Data System (ADS)

    Ruiter, Nicole V.; Zapf, Michael; Hopp, Torsten; Dapp, Robin; Gemmeke, Hartmut

    2014-03-01

    A promising candidate for improved imaging of breast cancer is ultrasound computer tomography (USCT). The aim of this work was to design a new aperture for our full 3D USCT which extends the properties of the current aperture to a larger ROI fitting the buoyant breast in water and decreasing artifacts in transmission tomography. The optimization resulted in a larger opening angle of the transducers, a larger diameter of the aperture and an approximately homogeneous distribution of the transducers, with locally random distances. The developed optimization methods allow us to automatically generate an optimized aperture for given diameters of apertures and transducer arrays, as well as quantitative comparison to other arbitrary apertures. Thus, during the design phase of the next generation KIT 3D USCT, the image quality can be balanced against the specification parameters and given hardware and cost limitations. The methods can be applied for general aperture optimization, only limited by the assumptions of a hemispherical aperture and circular transducer arrays.

  11. Computational Study of 3-D Hot-Spot Initiation in Shocked Insensitive High-Explosive

    NASA Astrophysics Data System (ADS)

    Najjar, F. M.; Howard, W. M.; Fried, L. E.

    2011-06-01

    High explosive shock sensitivity is controlled by a combination of mechanical response, thermal properties, and chemical properties. The interplay of these physical phenomena in realistic condensed energetic materials is currently lacking. A multiscale computational framework is developed investigating hot spot (void) ignition in a single crystal of an insensitive HE, TATB. Atomistic MD simulations are performed to provide the key chemical reactions and these reaction rates are used in 3-D multiphysics simulations. The multiphysics code, ALE3D, is linked to the chemistry software, Cheetah, and a three-way coupled approach is pursued including hydrodynamics, thermal and chemical analyses. A single spherical air bubble is embedded in the insensitive HE and its collapse due to shock initiation is evolved numerically in time; while the ignition processes due chemical reactions are studied. Our current predictions showcase several interesting features regarding hot spot dynamics including the formation of a ``secondary'' jet. Results obtained with hydro-thermo-chemical processes leading to ignition growth will be discussed for various pore sizes and different shock pressures. LLNL-ABS-471438. This work performed under the auspices of the U.S. Department of Energy by LLNL under Contract DE-AC52-07NA27344.

  12. Breast density measurement: 3D cone beam computed tomography (CBCT) images versus 2D digital mammograms

    NASA Astrophysics Data System (ADS)

    Han, Tao; Lai, Chao-Jen; Chen, Lingyun; Liu, Xinming; Shen, Youtao; Zhong, Yuncheng; Ge, Shuaiping; Yi, Ying; Wang, Tianpeng; Yang, Wei T.; Shaw, Chris C.

    2009-02-01

    Breast density has been recognized as one of the major risk factors for breast cancer. However, breast density is currently estimated using mammograms which are intrinsically 2D in nature and cannot accurately represent the real breast anatomy. In this study, a novel technique for measuring breast density based on the segmentation of 3D cone beam CT (CBCT) images was developed and the results were compared to those obtained from 2D digital mammograms. 16 mastectomy breast specimens were imaged with a bench top flat-panel based CBCT system. The reconstructed 3D CT images were corrected for the cupping artifacts and then filtered to reduce the noise level, followed by using threshold-based segmentation to separate the dense tissue from the adipose tissue. For each breast specimen, volumes of the dense tissue structures and the entire breast were computed and used to calculate the volumetric breast density. BI-RADS categories were derived from the measured breast densities and compared with those estimated from conventional digital mammograms. The results show that in 10 of 16 cases the BI-RADS categories derived from the CBCT images were lower than those derived from the mammograms by one category. Thus, breasts considered as dense in mammographic examinations may not be considered as dense with the CBCT images. This result indicates that the relation between breast cancer risk and true (volumetric) breast density needs to be further investigated.

  13. An improved version of NCOREL: A computer program for 3-D nonlinear supersonic potential flow computations

    NASA Technical Reports Server (NTRS)

    Siclari, Michael J.

    1988-01-01

    A computer code called NCOREL (for Nonconical Relaxation) has been developed to solve for supersonic full potential flows over complex geometries. The method first solves for the conical at the apex and then marches downstream in a spherical coordinate system. Implicit relaxation techniques are used to numerically solve the full potential equation at each subsequent crossflow plane. Many improvements have been made to the original code including more reliable numerics for computing wing-body flows with multiple embedded shocks, inlet flow through simulation, wake model and entropy corrections. Line relaxation or approximate factorization schemes are optionally available. Improved internal grid generation using analytic conformal mappings, supported by a simple geometric Harris wave drag input that was originally developed for panel methods and internal geometry package are some of the new features.

  14. The NCOREL computer program for 3D nonlinear supersonic potential flow computations

    NASA Technical Reports Server (NTRS)

    Siclari, M. J.

    1983-01-01

    An innovative computational technique (NCOREL) was established for the treatment of three dimensional supersonic flows. The method is nonlinear in that it solves the nonconservative finite difference analog of the full potential equation and can predict the formation of supercritical cross flow regions, embedded and bow shocks. The method implicitly computes a conical flow at the apex (R = 0) of a spherical coordinate system and uses a fully implicit marching technique to obtain three dimensional cross flow solutions. This implies that the radial Mach number must remain supersonic. The cross flow solutions are obtained by using type dependent transonic relaxation techniques with the type dependency linked to the character of the cross flow velocity (i.e., subsonic/supersonic). The spherical coordinate system and marching on spherical surfaces is ideally suited to the computation of wing flows at low supersonic Mach numbers due to the elimination of the subsonic axial Mach number problems that exist in other marching codes that utilize Cartesian transverse marching planes.

  15. A 3-D Computational Study of a Variable Camber Continuous Trailing Edge Flap (VCCTEF) Spanwise Segment

    NASA Technical Reports Server (NTRS)

    Kaul, Upender K.; Nguyen, Nhan T.

    2015-01-01

    Results of a computational study carried out to explore the effects of various elastomer configurations joining spanwise contiguous Variable Camber Continuous Trailing Edge Flap (VCCTEF) segments are reported here. This research is carried out as a proof-of-concept study that will seek to push the flight envelope in cruise with drag optimization as the objective. The cruise conditions can be well off design such as caused by environmental conditions, maneuvering, etc. To handle these off-design conditions, flap deflection is used so when the flap is deflected in a given direction, the aircraft angle of attack changes accordingly to maintain a given lift. The angle of attack is also a design parameter along with the flap deflection. In a previous 2D study,1 the effect of camber was investigated and the results revealed some insight into the relative merit of various camber settings of the VCCTEF. The present state of the art has not advanced sufficiently to do a full 3-D viscous analysis of the whole NASA Generic Transport Model (GTM) wing with VCCTEF deployed with elastomers. Therefore, this study seeks to explore the local effects of three contiguous flap segments on lift and drag of a model devised here to determine possible trades among various flap deflections to achieve desired lift and drag results. Although this approach is an approximation, it provides new insights into the "local" effects of the relative deflections of the contiguous spanwise flap systems and various elastomer segment configurations. The present study is a natural extension of the 2-D study to assess these local 3-D effects. Design cruise condition at 36,000 feet at free stream Mach number of 0.797 and a mean aerodynamic chord (MAC) based Reynolds number of 30.734x10(exp 6) is simulated for an angle of attack (AoA) range of 0 to 6 deg. In the previous 2-D study, the calculations revealed that the parabolic arc camber (1x2x3) and circular arc camber (VCCTEF222) offered the best L

  16. Effective Use of Computer Graphics in CAI: A Review of the Literature.

    ERIC Educational Resources Information Center

    Siliauskas, Gina

    1986-01-01

    Describes various new computer graphic display capabilities (e.g., animation of graphics and text, direct manipulation of on-screen graphics elements) and reviews relevant literature that could assist in determining how these new capabilities could be used effectively in computer assisted instruction applications. (Author/MBR)

  17. Hyperspeed data acquisition for 3D computer vision metrology as applied to law enforcement

    NASA Astrophysics Data System (ADS)

    Altschuler, Bruce R.

    1997-02-01

    cycling at 1 millisecond, each pattern is projected and recorded in a cycle time of 1/500th second. An entire set of patterns can then be recorded within 1/60th second. This pattern set contains all the information necessary to calculate a 3-D map. The use of hyper-speed parallel video cameras in conjunction with high speed modulators enables video data rate acquisition of all data necessary to calculate numerical digital 3-D metrological surface data. Thus a 3-D video camera can operate at the rate of a conventional 2-D video camera. The speed of actual 3-D output information is a function of the speed of the computer, a parallel processor being preferred for the task. With video rate 3-D data acquisition law enforcement could survey crime scenes, obtain evidence, watch and record people, packages, suitcases, and record disaster scenes very rapidly.

  18. The implementation of the graphics of program EAGLE: A numerical grid generation code on NASA Langley SNS computer system

    NASA Technical Reports Server (NTRS)

    Houston, Johnny L.

    1989-01-01

    Program EAGLE (Eglin Arbitrary Geometry Implicit Euler) Numerical Grid Generation System is a composite (multi-block) algebraic or elliptic grid generation system designed to discretize the domain in and/or around any arbitrarily shaped three dimensional regions. This system combines a boundary conforming surface generation scheme and includes plotting routines designed to take full advantage of the DISSPLA Graphics Package (Version 9.0). Program EAGLE is written to compile and execute efficiently on any Cray machine with or without solid state disk (SSD) devices. Also, the code uses namelist inputs which are supported by all Cray machines using the FORTRAN compiler CFT77. The namelist inputs makes it easier for the user to understand the inputs and operation of Program EAGLE. EAGLE's numerical grid generator is constructed in the following form: main program, EGG (executive routine); subroutine SURFAC (surface generation routine); subroutine GRID (grid generation routine); and subroutine GRDPLOT (grid plotting routines). The EAGLE code was modified to use on the NASA-LaRC SNS computer (Cray 2S) system. During the modification a conversion program was developed for the output data of EAGLE's subroutine GRID to permit the data to be graphically displayed by IRIS workstations, using Plot3D. The code of program EAGLE was modified to make operational subroutine GRDPLOT (using DI-3000 Graphics Software Packages) on the NASA-LaRC SNS Computer System. How to implement graphically, the output data of subroutine GRID was determined on any NASA-LaRC graphics terminal that has access to the SNS Computer System DI-300 Graphics Software Packages. A Quick Reference User Guide was developed for the use of program EAGLE on the NASA-LaRC SNS Computer System. One or more application program(s) was illustrated using program EAGLE on the NASA LaRC SNS Computer System, with emphasis on graphics illustrations.

  19. Roughness receptivity studies in a 3-D boundary layer - Flight tests and computations

    NASA Astrophysics Data System (ADS)

    Carpenter, Andrew L.; Saric, William S.; Reed, Helen L.

    The receptivity of 3-D boundary layers to micron-sized, spanwise-periodic Discrete Roughness Elements (DREs) was studied. The DREs were applied to the leading edge of a 30-degree swept-wing at the wavelength of the most unstable disturbance. In this case, calibrated, multi-element hotfilm sensors were used to measure disturbance wall shear stress. The roughness height was varied from 0 to 50 microns. Thus, the disturbance-shear-stress amplitude variations were determined as a function of modulated DRE heights. The computational work was conducted parallel to the flight experiments. The complete viscous flowfield over the O-2 aircraft with the SWIFT model mounted on the port wing store pylon was successfully modeled and validated with the flight data. This highly accurate basic-state solution was incorporated into linear stability calculations and the wave growth associated with the crossflow instability was calculated.

  20. Fast and Robust Sixth Order Multigrid Computation for 3D Convection Diffusion Equation

    PubMed Central

    Wang, Yin; Zhang, Jun

    2010-01-01

    We present a sixth order explicit compact finite difference scheme to solve the three dimensional (3D) convection diffusion equation. We first use multiscale multigrid method to solve the linear systems arising from a 19-point fourth order discretization scheme to compute the fourth order solutions on both the coarse grid and the fine grid. Then an operator based interpolation scheme combined with an extrapolation technique is used to approximate the sixth order accurate solution on the fine grid. Since the multigrid method using a standard point relaxation smoother may fail to achieve the optimal grid independent convergence rate for solving convection diffusion equation with a high Reynolds number, we implement the plane relaxation smoother in the multigrid solver to achieve better grid independency. Supporting numerical results are presented to demonstrate the efficiency and accuracy of the sixth order compact scheme (SOC), compared with the previously published fourth order compact scheme (FOC). PMID:21151737

  1. Development of complex 3D microstructures based on computer generated holography and their usage for biomedical applications

    NASA Astrophysics Data System (ADS)

    Palevicius, Arvydas; Grigaliunas, Viktoras; Janusas, Giedrius; Palevicius, Paulius; Sakalys, Rokas

    2016-04-01

    The main focus of the paper is the development of technological route of the production of complex 3D microstructure, from designing it by the method of computer generated holography till its physical 3D patterning by exploiting the process of electron beam lithography and thermal replication which is used for biomedical application. A phase data of a complex 3D microstructure was generated by using Gerchberg-Saxton algorithm which later was used to produce a computer generated hologram. Physical implementation of microstructure was done using a single layer polymethyl methacrylate (PMMA) as a basis for 3D microstructure, which was exposed using e-beam lithography system e-Line and replicated, using high frequency vibration. Manufactured 3D microstructure is used for designing micro sensor for biomedical applications.

  2. Computation of a high-resolution MRI 3D stereotaxic atlas of the sheep brain.

    PubMed

    Ella, Arsène; Delgadillo, José A; Chemineau, Philippe; Keller, Matthieu

    2017-02-15

    The sheep model was first used in the fields of animal reproduction and veterinary sciences and then was utilized in fundamental and preclinical studies. For more than a decade, magnetic resonance (MR) studies performed on this model have been increasingly reported, especially in the field of neuroscience. To contribute to MR translational neuroscience research, a brain template and an atlas are necessary. We have recently generated the first complete T1-weighted (T1W) and T2W MR population average images (or templates) of in vivo sheep brains. In this study, we 1) defined a 3D stereotaxic coordinate system for previously established in vivo population average templates; 2) used deformation fields obtained during optimized nonlinear registrations to compute nonlinear tissues or prior probability maps (nlTPMs) of cerebrospinal fluid (CSF), gray matter (GM), and white matter (WM) tissues; 3) delineated 25 external and 28 internal sheep brain structures by segmenting both templates and nlTPMs; and 4) annotated and labeled these structures using an existing histological atlas. We built a quality high-resolution 3D atlas of average in vivo sheep brains linked to a reference stereotaxic space. The atlas and nlTPMs, associated with previously computed T1W and T2W in vivo sheep brain templates and nlTPMs, provide a complete set of imaging space that are able to be imported into other imaging software programs and could be used as standardized tools for neuroimaging studies or other neuroscience methods, such as image registration, image segmentation, identification of brain structures, implementation of recording devices, or neuronavigation. J. Comp. Neurol. 525:676-692, 2017. © 2016 Wiley Periodicals, Inc.

  3. Ceramic scaffolds produced by computer-assisted 3D printing and sintering: characterization and biocompatibility investigations.

    PubMed

    Warnke, Patrick H; Seitz, Hermann; Warnke, Frauke; Becker, Stephan T; Sivananthan, Sureshan; Sherry, Eugene; Liu, Qin; Wiltfang, Jörg; Douglas, Timothy

    2010-04-01

    Hydroxyapatite (HAP) and tricalcium phosphate (TCP) are two very common ceramic materials for bone replacement. However, in general HAP and TCP scaffolds are not tailored to the exact dimensions of the defect site and are mainly used as granules or beads. Some scaffolds are available as ordinary blocks, but cannot be customized for individual perfect fit. Using computer-assisted 3D printing, an emerging rapid prototyping technique, individual three-dimensional ceramic scaffolds can be built up from TCP or HAP powder layer by layer with subsequent sintering. These scaffolds have precise dimensions and highly defined and regular internal characteristics such as pore size. External shape and internal characteristics such as pore size can be fabricated using Computer Assisted Design (CAD) based on individual patient data. Thus, these scaffolds could be designed as perfect fit replacements to reconstruct the patient's skeleton. Before their use as bone replacement materials in vivo, in vitro testing of these scaffolds is necessary. In this study, the behavior of human osteoblasts on HAP and TCP scaffolds was investigated. The commonly used bone replacement material BioOss(R) served as control. Biocompatibility was assessed by scanning electron microscopy (SEM), fluorescence microscopy after staining for cell vitality with fluorescin diacetate (FDA) and propidium iodide (PI) and the MTT, LDH, and WST biocompatibility tests. Both versions were colonised by human osteoblasts, however more cells were seen on HAP scaffolds than TCP scaffolds. Cell vitality staining and MTT, LDH, and WST tests showed superior biocompatibility of HAP scaffolds to BioOss, while BioOss was more compatible than TCP. Further experiments are necessary to determine biocompatibility in vivo. Future modifications of 3D printed scaffolds offer advantageous features for Tissue Engineering. The integration of channels could allow for vascular and nerve ingrowth into the scaffold. Also the complex shapes

  4. Analysis of bite marks in foodstuffs by computer tomography (cone beam CT)--3D reconstruction.

    PubMed

    Marques, Jeidson; Musse, Jamilly; Caetano, Catarina; Corte-Real, Francisco; Corte-Real, Ana Teresa

    2013-12-01

    The use of three-dimensional (3D) analysis of forensic evidence is highlighted in comparison with traditional methods. This three-dimensional analysis is based on the registration of the surface from a bitten object. The authors propose to use Cone Beam Computed Tomography (CBCT), which is used in dental practice, in order to study the surface and interior of bitten objects and dental casts of suspects. In this study, CBCT is applied to the analysis of bite marks in foodstuffs, which may be found in a forensic case scenario. 6 different types of foodstuffs were used: chocolate, cheese, apple, chewing gum, pizza and tart (flaky pastry and custard). The food was bitten into and dental casts of the possible suspects were made. The dental casts and bitten objects were registered using an x-ray source and the CBCT equipment iCAT® (Pennsylvania, EUA). The software InVivo5® (Anatomage Inc, EUA) was used to visualize and analyze the tomographic slices and 3D reconstructions of the objects. For each material an estimate of its density was assessed by two methods: HU values and specific gravity. All the used materials were successfully reconstructed as good quality 3D images. The relative densities of the materials in study were compared. Amongst the foodstuffs, the chocolate had the highest density (median value 100.5 HU and 1,36 g/cm(3)), while the pizza showed to have the lowest (median value -775 HU and 0,39 g/cm(3)), on both scales. Through tomographic slices and three-dimensional reconstructions it was possible to perform the metric analysis of the bite marks in all the foodstuffs, except for the pizza. These measurements could also be obtained from the dental casts. The depth of the bite mark was also successfully determined in all the foodstuffs except for the pizza. Cone Beam Computed Tomography has the potential to become an important tool for forensic sciences, namely for the registration and analysis of bite marks in foodstuffs that may be found in a crime

  5. Interaction of 3d transition metal atoms with charged ion projectiles from Electron Nuclear Dynamics computation

    NASA Astrophysics Data System (ADS)

    Hagelberg, Frank

    2003-03-01

    Computational results on atomic scattering between charged projectiles and transition metal target atoms are presented. This work aims at obtaining detailed information about charge, spin and energy transfer processes that occur between the interacting particles. An in-depth understanding of these phenomena is expected to provide a theoretical basis for the interpretation of various types of ion beam experiments, ranging from gas phase chromatography to spectroscopic observations of fast ions in ferromagnetic media. This contribution focuses on the scattering of light projectiles ranging from He to O, that are prepared in various initial charge states, by 3d transition metal atoms. The presented computations are performed in the framework of Electron Nuclear Dynamics (END)^1 theory which incorporates the coupling between electronic and nuclear degrees of freedom without reliance on the computationally cumbersome and frequently intractable determination of potential energy surfaces. In the present application of END theory to ion - transition metal atom scattering, a supermolecule approach is utilized in conjunction with a spin-unrestricted single determinantal wave function describing the electronic system. Integral scattering, charge and spin exchange cross sections are discussed as functions of the elementary parameters of the problem, such as projectile and target atomic numbers as well as projectile charge and initial kinetic energy. ^1 E.Deumens, A.Diz, R.Longo, Y.Oehrn, Rev.Mod.Phys. 66, 917 (1994)

  6. Enabling 3D-Liver Perfusion Mapping from MR-DCE Imaging Using Distributed Computing.

    PubMed

    Leporq, Benjamin; Camarasu-Pop, Sorina; Davila-Serrano, Eduardo E; Pilleul, Frank; Beuf, Olivier

    2013-01-01

    An MR acquisition protocol and a processing method using distributed computing on the European Grid Infrastructure (EGI) to allow 3D liver perfusion parametric mapping after Magnetic Resonance Dynamic Contrast Enhanced (MR-DCE) imaging are presented. Seven patients (one healthy control and six with chronic liver diseases) were prospectively enrolled after liver biopsy. MR-dynamic acquisition was continuously performed in free-breathing during two minutes after simultaneous intravascular contrast agent (MS-325 blood pool agent) injection. Hepatic capillary system was modeled by a 3-parameters one-compartment pharmacokinetic model. The processing step was parallelized and executed on the EGI. It was modeled and implemented as a grid workflow using the Gwendia language and the MOTEUR workflow engine. Results showed good reproducibility in repeated processing on the grid. The results obtained from the grid were well correlated with ROI-based reference method ran locally on a personal computer. The speed-up range was 71 to 242 with an average value of 126. In conclusion, distributed computing applied to perfusion mapping brings significant speed-up to quantification step to be used for further clinical studies in a research context. Accuracy would be improved with higher image SNR accessible on the latest 3T MR systems available today.

  7. A computational model of perceptual grouping and 3D surface completion in the mime effect.

    PubMed

    Mtibaa, Riadh; Idesawa, Masanori; Sakaguchi, Yutaka; Ishida, Fumihiko

    2008-09-01

    We propose a computational model of perceptual grouping for explaining the 3D shape representation of an illusory percept called "mime effect." This effect is associated with the generation of an illusory, volumetric perception that can be induced by particular distributions of inducing stimuli such as cones, whose orientations affect the stability of illusory perception. The authors have attempted to explain the characteristics of the shape representation of the mime effect using a neural network model that consists of four types of cells-encoding (E), normalizing (N), energetic (EN), and geometric (G) cells. E cells represent both the positions and orientations of inducing stimuli and the mime-effect shape, and N cells regulate the activity of E cells. The interactions of E cells generate dynamics whose mode indicates the stability of illusory perception; a stable dynamics mode indicates a stable perception, whereas a chaotic dynamics mode indicates an unstable perception. EN cells compute the Liapunov energetic exponent (LEE) from an energy function of the system of E cells. The stable and chaotic dynamics modes are identified by strictly negative and strictly positive values of LEE, respectively. In case of stability, G cells perform a particular surface interpolation for completing the mime effect shape. The authors confirm the model behaviour by means of computer-simulated experiments. The relation between the model behaviour and the shape representation in the human brain is also discussed.

  8. FURN3D: A computer code for radiative heat transfer in pulverized coal furnaces

    SciTech Connect

    Ahluwalia, R.K.; Im, K.H.

    1992-08-01

    A computer code FURN3D has been developed for assessing the impact of burning different coals on heat absorption pattern in pulverized coal furnaces. The code is unique in its ability to conduct detailed spectral calculations of radiation transport in furnaces fully accounting for the size distributions of char, soot and ash particles, ash content, and ash composition. The code uses a hybrid technique of solving the three-dimensional radiation transport equation for absorbing, emitting and anisotropically scattering media. The technique achieves an optimal mix of computational speed and accuracy by combining the discrete ordinate method (S[sub 4]), modified differential approximation (MDA) and P, approximation in different range of optical thicknesses. The code uses spectroscopic data for estimating the absorption coefficients of participating gases C0[sub 2], H[sub 2]0 and CO. It invokes Mie theory for determining the extinction and scattering coefficients of combustion particulates. The optical constants of char, soot and ash are obtained from dispersion relations derived from reflectivity, transmissivity and extinction measurements. A control-volume formulation is adopted for determining the temperature field inside the furnace. A simple char burnout model is employed for estimating heat release and evolution of particle size distribution. The code is written in Fortran 77, has modular form, and is machine-independent. The computer memory required by the code depends upon the number of grid points specified and whether the transport calculations are performed on spectral or gray basis.

  9. FURN3D: A computer code for radiative heat transfer in pulverized coal furnaces

    SciTech Connect

    Ahluwalia, R.K.; Im, K.H.

    1992-08-01

    A computer code FURN3D has been developed for assessing the impact of burning different coals on heat absorption pattern in pulverized coal furnaces. The code is unique in its ability to conduct detailed spectral calculations of radiation transport in furnaces fully accounting for the size distributions of char, soot and ash particles, ash content, and ash composition. The code uses a hybrid technique of solving the three-dimensional radiation transport equation for absorbing, emitting and anisotropically scattering media. The technique achieves an optimal mix of computational speed and accuracy by combining the discrete ordinate method (S{sub 4}), modified differential approximation (MDA) and P, approximation in different range of optical thicknesses. The code uses spectroscopic data for estimating the absorption coefficients of participating gases C0{sub 2}, H{sub 2}0 and CO. It invokes Mie theory for determining the extinction and scattering coefficients of combustion particulates. The optical constants of char, soot and ash are obtained from dispersion relations derived from reflectivity, transmissivity and extinction measurements. A control-volume formulation is adopted for determining the temperature field inside the furnace. A simple char burnout model is employed for estimating heat release and evolution of particle size distribution. The code is written in Fortran 77, has modular form, and is machine-independent. The computer memory required by the code depends upon the number of grid points specified and whether the transport calculations are performed on spectral or gray basis.

  10. Combining high performance simulation, data acquisition, and graphics display computers

    NASA Technical Reports Server (NTRS)

    Hickman, Robert J.

    1989-01-01

    Issues involved in the continuing development of an advanced simulation complex are discussed. This approach provides the capability to perform the majority of tests on advanced systems, non-destructively. The controlled test environments can be replicated to examine the response of the systems under test to alternative treatments of the system control design, or test the function and qualification of specific hardware. Field tests verify that the elements simulated in the laboratories are sufficient. The digital computer is hosted by a Digital Equipment Corp. MicroVAX computer with an Aptec Computer Systems Model 24 I/O computer performing the communication function. An Applied Dynamics International AD100 performs the high speed simulation computing and an Evans and Sutherland PS350 performs on-line graphics display. A Scientific Computer Systems SCS40 acts as a high performance FORTRAN program processor to support the complex, by generating numerous large files from programs coded in FORTRAN that are required for the real time processing. Four programming languages are involved in the process, FORTRAN, ADSIM, ADRIO, and STAPLE. FORTRAN is employed on the MicroVAX host to initialize and terminate the simulation runs on the system. The generation of the data files on the SCS40 also is performed with FORTRAN programs. ADSIM and ADIRO are used to program the processing elements of the AD100 and its IOCP processor. STAPLE is used to program the Aptec DIP and DIA processors.

  11. Color calculations for and perceptual assessment of computer graphic images

    SciTech Connect

    Meyer, G.W.

    1986-01-01

    Realistic image synthesis involves the modelling of an environment in accordance with the laws of physics and the production of a final simulation that is perceptually acceptable. To be considered a scientific endeavor, synthetic image generation should also include the final step of experimental verification. This thesis concentrates on the color calculations that are inherent in the production of the final simulation and on the perceptual assessment of the computer graphic images that result. The fundamental spectral sensitivity functions that are active in the human visual system are introduced and are used to address color-blindness issues in computer graphics. A digitally controlled color television monitor is employed to successfully implement both the Farnsworth Munsell 100 hues test and a new color vision test that yields more accurate diagnoses. Images that simulate color blind vision are synthesized and are used to evaluate color scales for data display. Gaussian quadrature is used with a set of opponent fundamental to select the wavelengths at which to perform synthetic image generation.

  12. A computer graphics display and data compression technique

    NASA Technical Reports Server (NTRS)

    Teague, M. J.; Meyer, H. G.; Levenson, L. (Editor)

    1974-01-01

    The computer program discussed is intended for the graphical presentation of a general dependent variable X that is a function of two independent variables, U and V. The required input to the program is the variation of the dependent variable with one of the independent variables for various fixed values of the other. The computer program is named CRP, and the output is provided by the SD 4060 plotter. Program CRP is an extremely flexible program that offers the user a wide variety of options. The dependent variable may be presented in either a linear or a logarithmic manner. Automatic centering of the plot is provided in the ordinate direction, and the abscissa is scaled automatically for a logarithmic plot. A description of the carpet plot technique is given along with the coordinates system used in the program. Various aspects of the program logic are discussed and detailed documentation of the data card format is presented.

  13. Solar physics applications of computer graphics and image processing

    NASA Technical Reports Server (NTRS)

    Altschuler, M. D.

    1985-01-01

    Computer graphics devices coupled with computers and carefully developed software provide new opportunities to achieve insight into the geometry and time evolution of scalar, vector, and tensor fields and to extract more information quickly and cheaply from the same image data. Two or more different fields which overlay in space can be calculated from the data (and the physics), then displayed from any perspective, and compared visually. The maximum regions of one field can be compared with the gradients of another. Time changing fields can also be compared. Images can be added, subtracted, transformed, noise filtered, frequency filtered, contrast enhanced, color coded, enlarged, compressed, parameterized, and histogrammed, in whole or section by section. Today it is possible to process multiple digital images to reveal spatial and temporal correlations and cross correlations. Data from different observatories taken at different times can be processed, interpolated, and transformed to a common coordinate system.

  14. Use of computer graphics for visualization of flow fields

    NASA Technical Reports Server (NTRS)

    Watson, Val; Buning, Pieter; Choi, Diana; Bancroft, Gordon; Merritt, Fergus; Rogers, Stuart

    1987-01-01

    A high-performance graphics workstation has been combined with software developed for flow-field visualization to yield a highly effective tool for analysis of fluid-flow dynamics. After the flow fields are obtained from experimental measurements or computer simulations, the workstation permits one to interactively view the dynamics of the flow fields; e.g., the viewer can zoom into a region or rotate his viewing position about the region to study it in more detail. Several techniques for visualization of flow fields with this workstation are described in this paper and illustrated with a videotape available from the authors. The computer hardware and software required to create effective flow visualization displays are discussed. Additional software and hardware required to create videotapes or 16mm movies are also described. Limitations imposed by current workstation performance is addressed and future workstation performance is forecast.

  15. Solar physics applications of computer graphics and image processing

    NASA Technical Reports Server (NTRS)

    Altschuler, M. D.

    1985-01-01

    Computer graphics devices coupled with computers and carefully developed software provide new opportunities to achieve insight into the geometry and time evolution of scalar, vector, and tensor fields and to extract more information quickly and cheaply from the same image data. Two or more different fields which overlay in space can be calculated from the data (and the physics), then displayed from any perspective, and compared visually. The maximum regions of one field can be compared with the gradients of another. Time changing fields can also be compared. Images can be added, subtracted, transformed, noise filtered, frequency filtered, contrast enhanced, color coded, enlarged, compressed, parameterized, and histogrammed, in whole or section by section. Today it is possible to process multiple digital images to reveal spatial and temporal correlations and cross correlations. Data from different observatories taken at different times can be processed, interpolated, and transformed to a common coordinate system.

  16. A Computational Method for 3D Anisotropic Travel-time Tomography of Rocks in the Laboratory

    NASA Astrophysics Data System (ADS)

    Ghofranitabari, Mehdi; Young, R. Paul

    2013-04-01

    True triaxial loading in the laboratory applies three principal stresses on a cubic rock specimen. Elliptical anisotropy and distributed heterogeneities are introduced in the rock due to closure and opening of the pre-existing cracks and creation and growth of the new aligned cracks. The rock sample is tested in a Geophysical Imaging Cell that is armed with an Acoustic Emission monitoring system which can perform transducer to transducer velocity surveys to image velocity structure of the sample during the experiment. Ultrasonic travel-time tomography as a non-destructive method outfits a map of wave propagation velocity in the sample in order to detect the uniformly distributed or localised heterogeneities and provide the spatial variation and temporal evolution of induced damages in rocks at various stages of loading. The rock sample is partitioned into cubic grid cells as model space. Ray-based tomography method measuring body wave travel time along ray paths between pairs of emitting and receiving transducers is used to calculate isotropic ray-path segment matrix elements (Gij) which contain segment lengths of the ith ray in the jth cell in three dimensions. Synthetic P wave travel times are computed between pairs of transducers in a hypothetical isotropic heterogeneous cubic sample as data space along with an error due to precision of measurement. 3D strain of the squeezed rock and the consequent geometrical deformation is also included in computations for further accuracy. Singular Value Decomposition method is used for the inversion from data space to model space. In the next step, the anisotropic ray-path segment matrix and the corresponded data space are computed for hypothetical anisotropic heterogeneous samples based on the elliptical anisotropic model of velocity which is obtained from the real laboratory experimental data. The method is examined for several different synthetic heterogeneous models. An "Inaccuracy factor" is utilized to inquire the

  17. Engineering computer graphics in gas turbine engine design, analysis and manufacture

    NASA Technical Reports Server (NTRS)

    Lopatka, R. S.

    1975-01-01

    A time-sharing and computer graphics facility designed to provide effective interactive tools to a large number of engineering users with varied requirements was described. The application of computer graphics displays at several levels of hardware complexity and capability is discussed, with examples of graphics systems tracing gas turbine product development, beginning with preliminary design through manufacture. Highlights of an operating system stylized for interactive engineering graphics is described.

  18. A supervisor for the successive 3D computations of magnetic, mechanical and acoustic quantities in power oil inductors and transformers

    SciTech Connect

    Reyne, G.; Magnin, H.; Berliat, G.; Clerc, C.

    1994-09-01

    A supervisor has been developed so as to allow successive 3D computations of different quantities by different softwares on the same physical problem. Noise of a given power oil transformer can be deduced from the surface vibrations of the tank. These vibrations are obtained through a mechanic computation whose Inputs are the electromagnetic forces provided . by an electromagnetic computation. Magnetic, mechanic and acoustic experimental data are compared with the results of the 3D computations. Stress Is put on the main characteristics of the supervisor such as the transfer of a given quantity from one mesh to the other.

  19. A new 3D texture feature based computer-aided diagnosis approach to differentiate pulmonary nodules

    NASA Astrophysics Data System (ADS)

    Han, Fangfang; Wang, Huafeng; Song, Bowen; Zhang, Guopeng; Lu, Hongbing; Moore, William; Zhao, Hong; Liang, Zhengrong

    2013-02-01

    To distinguish malignant pulmonary nodules from benign ones is of much importance in computer-aided diagnosis of lung diseases. Compared to many previous methods which are based on shape or growth assessing of nodules, this proposed three-dimensional (3D) texture feature based approach extracted fifty kinds of 3D textural features from gray level, gradient and curvature co-occurrence matrix, and more derivatives of the volume data of the nodules. To evaluate the presented approach, the Lung Image Database Consortium public database was downloaded. Each case of the database contains an annotation file, which indicates the diagnosis results from up to four radiologists. In order to relieve partial-volume effect, interpolation process was carried out to those volume data with image slice thickness more than 1mm, and thus we had categorized the downloaded datasets to five groups to validate the proposed approach, one group of thickness less than 1mm, two types of thickness range from 1mm to 1.25mm and greater than 1.25mm (each type contains two groups, one with interpolation and the other without). Since support vector machine is based on statistical learning theory and aims to learn for predicting future data, so it was chosen as the classifier to perform the differentiation task. The measure on the performance was based on the area under the curve (AUC) of Receiver Operating Characteristics. From 284 nodules (122 malignant and 162 benign ones), the validation experiments reported a mean of 0.9051 and standard deviation of 0.0397 for the AUC value on average over 100 randomizations.

  20. Potential hazards of viewing 3-D stereoscopic television, cinema and computer games: a review.

    PubMed

    Howarth, Peter A

    2011-03-01

    The visual stimulus provided by a 3-D stereoscopic display differs from that of the real world because the image provided to each eye is produced on a flat surface. The distance from the screen to the eye remains fixed, providing a single focal distance, but the introduction of disparity between the images allows objects to be located geometrically in front of, or behind, the screen. Unlike in the real world, the stimulus to accommodation and the stimulus to convergence do not match. Although this mismatch is used positively in some forms of Orthoptic treatment, a number of authors have suggested that it could negatively lead to the development of asthenopic symptoms. From knowledge of the zone of clear, comfortable, single binocular vision one can predict that, for people with normal binocular vision, adverse symptoms will not be present if the discrepancy is small, but are likely if it is large, and that what constitutes 'large' and 'small' are idiosyncratic to the individual. The accommodation-convergence mismatch is not, however, the only difference between the natural and the artificial stimuli. In the former case, an object located in front of, or behind, a fixated object will not only be perceived as double if the images fall outside Panum's fusional areas, but it will also be defocused and blurred. In the latter case, however, it is usual for the producers of cinema, TV or computer game content to provide an image that is in focus over the whole of the display, and as a consequence diplopic images will be sharply in focus. The size of Panum's fusional area is spatial frequency-dependent, and because of this the high spatial frequencies present in the diplopic 3-D image will provide a different stimulus to the fusion system from that found naturally. © 2011 The College of Optometrists.

  1. Projection-based metal-artifact reduction for industrial 3D X-ray computed tomography.

    PubMed

    Amirkhanov, Artem; Heinzl, Christoph; Reiter, Michael; Kastner, Johann; Gröller, M Eduard

    2011-12-01

    Multi-material components, which contain metal parts surrounded by plastic materials, are highly interesting for inspection using industrial 3D X-ray computed tomography (3DXCT). Examples of this application scenario are connectors or housings with metal inlays in the electronic or automotive industry. A major problem of this type of components is the presence of metal, which causes streaking artifacts and distorts the surrounding media in the reconstructed volume. Streaking artifacts and dark-band artifacts around metal components significantly influence the material characterization (especially for the plastic components). In specific cases these artifacts even prevent a further analysis. Due to the nature and the different characteristics of artifacts, the development of an efficient artifact-reduction technique in reconstruction-space is rather complicated. In this paper we present a projection-space pipeline for metal-artifacts reduction. The proposed technique first segments the metal in the spatial domain of the reconstructed volume in order to separate it from the other materials. Then metal parts are forward-projected on the set of projections in a way that metal-projection regions are treated as voids. Subsequently the voids, which are left by the removed metal, are interpolated in the 2D projections. Finally, the metal is inserted back into the reconstructed 3D volume during the fusion stage. We present a visual analysis tool, allowing for interactive parameter estimation of the metal segmentation. The results of the proposed artifact-reduction technique are demonstrated on a test part as well as on real world components. For these specimens we achieve a significant reduction of metal artifacts, allowing an enhanced material characterization. © 2010 IEEE

  2. Parallel computing simulation of electrical excitation and conduction in the 3D human heart.

    PubMed

    Di Yu; Dongping Du; Hui Yang; Yicheng Tu

    2014-01-01

    A correctly beating heart is important to ensure adequate circulation of blood throughout the body. Normal heart rhythm is produced by the orchestrated conduction of electrical signals throughout the heart. Cardiac electrical activity is the resulted function of a series of complex biochemical-mechanical reactions, which involves transportation and bio-distribution of ionic flows through a variety of biological ion channels. Cardiac arrhythmias are caused by the direct alteration of ion channel activity that results in changes in the AP waveform. In this work, we developed a whole-heart simulation model with the use of massive parallel computing with GPGPU and OpenGL. The simulation algorithm was implemented under several different versions for the purpose of comparisons, including one conventional CPU version and two GPU versions based on Nvidia CUDA platform. OpenGL was utilized for the visualization / interaction platform because it is open source, light weight and universally supported by various operating systems. The experimental results show that the GPU-based simulation outperforms the conventional CPU-based approach and significantly improves the speed of simulation. By adopting modern computer architecture, this present investigation enables real-time simulation and visualization of electrical excitation and conduction in the large and complicated 3D geometry of a real-world human heart.

  3. Novel 3D hexapod computer-assisted orthopaedic surgery system for closed diaphyseal fracture reduction.

    PubMed

    Tang, Peifu; Hu, Lei; Du, Hailong; Gong, Minli; Zhang, Lihai

    2012-03-01

    Long-bone fractures are very common in trauma centers. The conventional Arbeitsgemeindschaft fur Osteosynthesefragen (AO) technique contributes to most fracture healing problems, and external fixation technology also has several disadvantages, so new techniques are being explored. A novel hexapod computer-assisted fracture reduction system based on a 3D-CT image reconstruction process is presented for closed reduction of long-bone diaphyseal fractures. A new reduction technique and upgraded reduction device are described and the whole system has been validated. Ten bovine femoral fracture models were used with random fracture patterns. Tests results were as follows: residual deviation 1.24 + 0.65 mm for the axial deflection, 1.19 + 0.37 mm for the translation, 2.34 + 1.79° for the angulation, and 2.83 + 0.9° for the rotation. The reduction mechanism has the advantages of high positioning, reduction and computer accuracy, and intra-operative stability for both patients and surgical team. With further investigation, it could be applied in many kinds of long-bone diaphyseal fractures. Copyright © 2011 John Wiley & Sons, Ltd.

  4. Human identification through frontal sinus 3D superimposition: Pilot study with Cone Beam Computer Tomography.

    PubMed

    Beaini, Thiago Leite; Duailibi-Neto, Eduardo F; Chilvarquer, Israel; Melani, Rodolfo F H

    2015-11-01

    As a unique anatomical feature of the human body, the frontal sinus morphology has been used for identification of unknown bodies with many techniques, mostly using 2D postero-anterior X-rays. With the increase of the use of Cone-Beam Computer Tomography (CBCT), the availability of this exam as ante-mortem records should be considered. The purpose of this study is to establish a new technique for frontal sinus identification through direct superimposition of 3D volumetric models obtained from CBCT exam, by testing two distinct situations. First, a reproducibility test, where two observers independently rendered models of frontal sinus from a sample 20 CBCT exams and identified them on each other's list. In the second situation, one observer tested the protocol and established on different exams of three individual. Using the open source DICOM viewer InVesallius(®) for rendering, Mesh Lab(®,) for positioning the models and CloudCompare for volumetric comparison, both observers matched cases with 100% accuracy and the level of coincidence in a identification situation. The uniqueness of the frontal sinus topography is remarkable and through the described technique, can be used in forensic as an identification method whenever both the sinus structure and antemortem computer tomography is available. Copyright © 2015 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  5. Quantification of substrate and cellular strains in stretchable 3D cell cultures: an experimental and computational framework.

    PubMed

    González-Avalos, P; Mürnseer, M; Deeg, J; Bachmann, A; Spatz, J; Dooley, S; Eils, R; Gladilin, E

    2017-05-01

    The mechanical cell environment is a key regulator of biological processes . In living tissues, cells are embedded into the 3D extracellular matrix and permanently exposed to mechanical forces. Quantification of the cellular strain state in a 3D matrix is therefore the first step towards understanding how physical cues determine single cell and multicellular behaviour. The majority of cell assays are, however, based on 2D cell cultures that lack many essential features of the in vivo cellular environment. Furthermore, nondestructive measurement of substrate and cellular mechanics requires appropriate computational tools for microscopic image analysis and interpretation. Here, we present an experimental and computational framework for generation and quantification of the cellular strain state in 3D cell cultures using a combination of 3D substrate stretcher, multichannel microscopic imaging and computational image analysis. The 3D substrate stretcher enables deformation of living cells embedded in bead-labelled 3D collagen hydrogels. Local substrate and cell deformations are determined by tracking displacement of fluorescent beads with subsequent finite element interpolation of cell strains over a tetrahedral tessellation. In this feasibility study, we debate diverse aspects of deformable 3D culture construction, quantification and evaluation, and present an example of its application for quantitative analysis of a cellular model system based on primary mouse hepatocytes undergoing transforming growth factor (TGF-β) induced epithelial-to-mesenchymal transition. © 2017 The Authors. Journal of Microscopy published by JohnWiley & Sons Ltd on behalf of Royal Microscopical Society.

  6. Open-Source Assisted Laboratory Automation through Graphical User Interfaces and 3D Printers: Application to Equipment Hyphenation for Higher-Order Data Generation.

    PubMed

    Siano, Gabriel G; Montemurro, Milagros; Alcaráz, Mirta R; Goicoechea, Héctor C

    2017-09-25

    Higher-order data generation implies some automation challenges, which are mainly related to the hidden programming languages and electronic details of the equipment. When techniques and/or equipment hyphenation are the key to obtaining higher-order data, the required simultaneous control of them demands funds for new hardware, software, and licenses, in addition to very skilled operators. In this work, we present Design of Inputs-Outputs with Sikuli (DIOS), a free and open-source code program that provides a general framework for the design of automated experimental procedures without prior knowledge of programming or electronics. Basically, instruments and devices are considered as nodes in a network, and every node is associated both with physical and virtual inputs and outputs. Virtual components, such as graphical user interfaces (GUIs) of equipment, are handled by means of image recognition tools provided by Sikuli scripting language, while handling of their physical counterparts is achieved using an adapted open-source three-dimensional (3D) printer. Two previously reported experiments of our research group, related to fluorescence matrices derived from kinetics and high-performance liquid chromatography, were adapted to be carried out in a more automated fashion. Satisfactory results, in terms of analytical performance, were obtained. Similarly, advantages derived from open-source tools assistance could be appreciated, mainly in terms of lesser intervention of operators and cost savings.

  7. Graphics processing units in bioinformatics, computational biology and systems biology.

    PubMed

    Nobile, Marco S; Cazzaniga, Paolo; Tangherloni, Andrea; Besozzi, Daniela

    2017-09-01

    Several studies in Bioinformatics, Computational Biology and Systems Biology rely on the definition of physico-chemical or mathematical models of biological systems at different scales and levels of complexity, ranging from the interaction of atoms in single molecules up to genome-wide interaction networks. Traditional computational methods and software tools developed in these research fields share a common trait: they can be computationally demanding on Central Processing Units (CPUs), therefore limiting their applicability in many circumstances. To overcome this issue, general-purpose Graphics Processing Units (GPUs) are gaining an increasing attention by the scientific community, as they can considerably reduce the running time required by standard CPU-based software, and allow more intensive investigations of biological systems. In this review, we present a collection of GPU tools recently developed to perform computational analyses in life science disciplines, emphasizing the advantages and the drawbacks in the use of these parallel architectures. The complete list of GPU-powered tools here reviewed is available at http://bit.ly/gputools. © The Author 2016. Published by Oxford University Press.

  8. Accelerating sino-atrium computer simulations with graphic processing units.

    PubMed

    Zhang, Hong; Xiao, Zheng; Lin, Shien-fong

    2015-01-01

    Sino-atrial node cells (SANCs) play a significant role in rhythmic firing. To investigate their role in arrhythmia and interactions with the atrium, computer simulations based on cellular dynamic mathematical models are generally used. However, the large-scale computation usually makes research difficult, given the limited computational power of Central Processing Units (CPUs). In this paper, an accelerating approach with Graphic Processing Units (GPUs) is proposed in a simulation consisting of the SAN tissue and the adjoining atrium. By using the operator splitting method, the computational task was made parallel. Three parallelization strategies were then put forward. The strategy with the shortest running time was further optimized by considering block size, data transfer and partition. The results showed that for a simulation with 500 SANCs and 30 atrial cells, the execution time taken by the non-optimized program decreased 62% with respect to a serial program running on CPU. The execution time decreased by 80% after the program was optimized. The larger the tissue was, the more significant the acceleration became. The results demonstrated the effectiveness of the proposed GPU-accelerating methods and their promising applications in more complicated biological simulations.

  9. uPy: a ubiquitous computer graphics Python API with Biological Modeling Applications

    PubMed Central

    Autin, L.; Johnson, G.; Hake, J.; Olson, A.; Sanner, M.

    2015-01-01

    In this paper we describe uPy, an extension module for the Python programming language that provides a uniform abstraction of the APIs of several 3D computer graphics programs called hosts, including: Blender, Maya, Cinema4D, and DejaVu. A plugin written with uPy is a unique piece of code that will run in all uPy-supported hosts. We demonstrate the creation of complex plug-ins for molecular/cellular modeling and visualization and discuss how uPy can more generally simplify programming for many types of projects (not solely science applications) intended for multi-host distribution. uPy is available at http://upy.scripps.edu PMID:24806987

  10. Computational identification and quantification of trabecular microarchitecture classes by 3-D texture analysis-based clustering.

    PubMed

    Valentinitsch, Alexander; Patsch, Janina M; Burghardt, Andrew J; Link, Thomas M; Majumdar, Sharmila; Fischer, Lukas; Schueller-Weidekamm, Claudia; Resch, Heinrich; Kainberger, Franz; Langs, Georg

    2013-05-01

    High resolution peripheral quantitative computed tomography (HR-pQCT) permits the non-invasive assessment of cortical and trabecular bone density, geometry, and microarchitecture. Although researchers have developed various post-processing algorithms to quantify HR-pQCT image properties, few of these techniques capture image features beyond global structure-based metrics. While 3D-texture analysis is a key approach in computer vision, it has been utilized only infrequently in HR-pQCT research. Motivated by high isotropic spatial resolution and the information density provided by HR-pQCT scans, we have developed and evaluated a post-processing algorithm that quantifies microarchitecture characteristics via texture features in HR-pQCT scans. During a training phase in which clustering was applied to texture features extracted from each voxel of trabecular bone, three distinct clusters, or trabecular microarchitecture classes (TMACs) were identified. These TMACs represent trabecular bone regions with common texture characteristics. The TMACs were then used to automatically segment the voxels of new data into three regions corresponding to the trained cluster features. Regional trabecular bone texture was described by the histogram of relative trabecular bone volume covered by each cluster. We evaluated the intra-scanner and inter-scanner reproducibility by assessing the precision errors (PE), intra class correlation coefficients (ICC) and Dice coefficients (DC) of the method on 14 ultradistal radius samples scanned on two HR-pQCT systems. DC showed good reproducibility in intra-scanner set-up with a mean of 0.870±0.027 (no unit). Even in the inter-scanner set-up the ICC showed high reproducibility, ranging from 0.814 to 0.964. In a preliminary clinical test application, the TMAC histograms appear to be a good indicator, when differentiating between postmenopausal women with (n=18) and without (n=18) prevalent fragility fractures. In conclusion, we could demonstrate

  11. Computer-assisted diagnostic system for neurodegenerative dementia using brain SPECT and 3D-SSP.

    PubMed

    Ishii, Kazunari; Kanda, Tomonori; Uemura, Takafumi; Miyamoto, Naokazu; Yoshikawa, Toshiki; Shimada, Kenichi; Ohkawa, Shingo; Minoshima, Satoshi

    2009-05-01

    To develop a computer-assisted automated diagnostic system to distinguish among Alzheimer disease (AD), dementia with Lewy bodies (DLB), and other degenerative disorders in patients with mild dementia. Single photon emission computed tomography (SPECT) images with injection of N-Isopropyl-p-[(123)I]iodoamphetamine (IMP) were obtained from patients with mild degenerative dementia. First, datasets from 20 patients mild AD, 15 patients with dementia with DLB, and 17 healthy controls were used to develop an automated diagnosing system based on three-dimensional stereotactic surface projections (3D-SSP). AD- and DLB-specific regional templates were created using 3D-SSP, and critical Z scores in the templates were established. Datasets from 50 AD patients, 8 DLB patients, and 10 patients with non-AD/DLB type degenerative dementia (5 with frontotemporal dementia and 5 with progressive supranuclear palsy) were then used to test the diagnostic accuracy of the optimized automated system in comparison to the diagnostic interpretation of conventional IMP-SPECT images. These comparisons were performed to differentiate AD and DLB from non-AD/DLB and to distinguish AD from DLB. A receiver operating characteristic (ROC) analysis was performed. The area under the ROC curve (Az) and the accuracy of the automated diagnosis system were 0.89 and 82%, respectively, for AD/DLB vs. non-AD/DLB patients, and 0.70 and 65%, respectively, for AD vs. DLB patients. The mean Az and the accuracy of the visual inspection were 0.84 and 77%, respectively, for AD/DLB vs. non-AD/DLB patients, and 0.70 and 65%, respectively, for AD vs. DLB patients. The mean Az and the accuracy of the combination of visual inspection and this system were 0.96 and 91%, respectively, for AD/DLB vs. non-AD/DLB patients, and 0.70 and 66%, respectively, for AD vs. DLB patients. The system developed in the present study achieved as good discrimination of AD, DLB, and other degenerative disorders in patients with mild dementia

  12. GRID2D/3D: A computer program for generating grid systems in complex-shaped two- and three-dimensional spatial domains. Part 2: User's manual and program listing

    NASA Technical Reports Server (NTRS)

    Bailey, R. T.; Shih, T. I.-P.; Nguyen, H. L.; Roelke, R. J.

    1990-01-01

    An efficient computer program, called GRID2D/3D, was developed to generate single and composite grid systems within geometrically complex two- and three-dimensional (2- and 3-D) spatial domains that can deform with time. GRID2D/3D generates single grid systems by using algebraic grid generation methods based on transfinite interpolation in which the distribution of grid points within the spatial domain is controlled by stretching functions. All single grid systems generated by GRID2D/3D can have grid lines that are continuous and differentiable everywhere up to the second-order. Also, grid lines can intersect boundaries of the spatial domain orthogonally. GRID2D/3D generates composite grid systems by patching together two or more single grid systems. The patching can be discontinuous or continuous. For continuous composite grid systems, the grid lines are continuous and differentiable everywhere up to the second-order except at interfaces where different single grid systems meet. At interfaces where different single grid systems meet, the grid lines are only differentiable up to the first-order. For 2-D spatial domains, the boundary curves are described by using either cubic or tension spline interpolation. For 3-D spatial domains, the boundary surfaces are described by using either linear Coon's interpolation, bi-hyperbolic spline interpolation, or a new technique referred to as 3-D bi-directional Hermite interpolation. Since grid systems generated by algebraic methods can have grid lines that overlap one another, GRID2D/3D contains a graphics package for evaluating the grid systems generated. With the graphics package, the user can generate grid systems in an interactive manner with the grid generation part of GRID2D/3D. GRID2D/3D is written in FORTRAN 77 and can be run on any IBM PC, XT, or AT compatible computer. In order to use GRID2D/3D on workstations or mainframe computers, some minor modifications must be made in the graphics part of the program; no

  13. A Computer Graphics Human Figure Application Of Biostereometrics

    NASA Astrophysics Data System (ADS)

    Fetter, William A.

    1980-07-01

    A study of improved computer graphic representation of the human figure is being conducted under a National Science Foundation grant. Special emphasis is given biostereometrics as a primary data base from which applications requiring a variety of levels of detail may be prepared. For example, a human figure represented by a single point can be very useful in overview plots of a population. A crude ten point figure can be adequate for queuing theory studies and simulated movement of groups. A one hundred point figure can usefully be animated to achieve different overall body activities including male and female figures. A one thousand point figure si-milarly animated, begins to be useful in anthropometrics and kinesiology gross body movements. Extrapolations of this order-of-magnitude approach ultimately should achieve very complex data bases and a program which automatically selects the correct level of detail for the task at hand. See Summary Figure 1.

  14. STS-49 ASEM activities illustrated with PLAID computer graphics

    NASA Technical Reports Server (NTRS)

    1992-01-01

    STS-49 Endeavour, Orbiter Vehicle (OV) 105, Assembly of Station by Extravehicular Activity (EVA) Methods (ASEM) activities are illustrated with PLAID computer graphics. An extravehicular mobility unit (EMU) suited crewmember, positioned on the remote manipulator system (RMS) manipulator foot restraint (MFR), grabs and maneuvers the multipurpose experiment support structure (MPESS) above OV-105's payload bay (PLB) using the steering wheel assembly. Once in position the MPESS will be attached to the truss assembly. The crewmember lifting the MPESS out of the PLB is evaluating mass manipulation and berthing of a relatively large mass. This will simulate techniques to be used for module-to-truss installation for Space Station Freedom (SSF). A second EMU suited crewmember oversees and directs the MPESS manipulation from a portable foot restraint (PFR) attached to the starboard sill longeron.

  15. STS-49 ASEM activity illustrated with PLAID computer graphics

    NASA Technical Reports Server (NTRS)

    1992-01-01

    STS-49 Endeavour, Orbiter Vehicle (OV) 105, Assembly of Station by Extravehicular Activity (EVA) Methods (ASEM) activity is illustrated with PLAID computer graphics. An extravehicular mobility unit (EMU) suited crewmember, positioned on the remote manipulator system (RMS) manipulator foot restraint (MFR), grabs and maneuvers the multipurpose experiment support structure (MPESS) with truss assembly attached above OV-105's payload bay (PLB) using the steer wheel assembly. The MPESS/ASEM truss structure has been lifted out the sill-mounted payload retention latch assemblies (PRLAs) and will be repositioned in the PRLAs upon completion of handling procedures. Also seen in this illustration are the empty INTELSAT perigee stage cradle structure (aft PLB) and the capture bar grapple fixture stowed on the port side sill longeron.

  16. Designing Computer Graphics: An Experiment in the Graphic Enhancement of Audio Teleconferencing.

    ERIC Educational Resources Information Center

    Winn, Bill; And Others

    Two distance education courses presented via teleconferencing by the University of Calgary were redesigned to include graphic support utilizing Canada's Telidon videotex system. Data were gathered on both the instructional effectiveness of and student responses to the graphics. While the evaluation pointed out a number of features that needed to…

  17. Memory usage reduction and intensity modulation for 3D holographic display using non-uniformly sampled computer-generated holograms

    NASA Astrophysics Data System (ADS)

    Zhang, Zhao; Liu, Juan; Jia, Jia; Li, Xin; Pan, Yijie; Han, Jian; Hu, Bin; Wang, Yongtian

    2013-12-01

    The real-time holographic display encounters heavy computational load of computer-generated holograms and precisely intensity modulation of 3D images reconstructed by phase-only holograms. In this study, we demonstrate a method for reducing memory usage and modulating the intensity in 3D holographic display. The proposed method can eliminate the redundant information of holograms by employing the non-uniform sampling technique. By combining with the novel look-up table method, 70% reduction in the storage amount can be reached. The gray-scale modulation of 3D images reconstructed by phase-only holograms can be extended either. We perform both numerical simulations and optical experiments to verify the practicability of this method, and the results match well with each other. It is believed that the proposed method can be used in 3D dynamic holographic display and design of the diffractive phase elements.

  18. Automatic validation of computational models using pseudo-3D spatio-temporal model checking.

    PubMed

    Pârvu, Ovidiu; Gilbert, David

    2014-12-02

    Computational models play an increasingly important role in systems biology for generating predictions and in synthetic biology as executable prototypes/designs. For real life (clinical) applications there is a need to scale up and build more complex spatio-temporal multiscale models; these could enable investigating how changes at small scales reflect at large scales and viceversa. Results generated by computational models can be applied to real life applications only if the models have been validated first. Traditional in silico model checking techniques only capture how non-dimensional properties (e.g. concentrations) evolve over time and are suitable for small scale systems (e.g. metabolic pathways). The validation of larger scale systems (e.g. multicellular populations) additionally requires capturing how spatial patterns and their properties change over time, which are not considered by traditional non-spatial approaches. We developed and implemented a methodology for the automatic validation of computational models with respect to both their spatial and temporal properties. Stochastic biological systems are represented by abstract models which assume a linear structure of time and a pseudo-3D representation of space (2D space plus a density measure). Time series data generated by such models is provided as input to parameterised image processing modules which automatically detect and analyse spatial patterns (e.g. cell) and clusters of such patterns (e.g. cellular population). For capturing how spatial and numeric properties change over time the Probabilistic Bounded Linear Spatial Temporal Logic is introduced. Given a collection of time series data and a formal spatio-temporal specification the model checker Mudi ( http://mudi.modelchecking.org ) determines probabilistically if the formal specification holds for the computational model or not. Mudi is an approximate probabilistic model checking platform which enables users to choose between frequentist and

  19. A new approach of building 3D visualization framework for multimodal medical images display and computed assisted diagnosis

    NASA Astrophysics Data System (ADS)

    Li, Zhenwei; Sun, Jianyong; Zhang, Jianguo

    2012-02-01

    As more and more CT/MR studies are scanning with larger volume of data sets, more and more radiologists and clinician would like using PACS WS to display and manipulate these larger data sets of images with 3D rendering features. In this paper, we proposed a design method and implantation strategy to develop 3D image display component not only with normal 3D display functions but also with multi-modal medical image fusion as well as compute-assisted diagnosis of coronary heart diseases. The 3D component has been integrated into the PACS display workstation of Shanghai Huadong Hospital, and the clinical practice showed that it is easy for radiologists and physicians to use these 3D functions such as multi-modalities' (e.g. CT, MRI, PET, SPECT) visualization, registration and fusion, and the lesion quantitative measurements. The users were satisfying with the rendering speeds and quality of 3D reconstruction. The advantages of the component include low requirements for computer hardware, easy integration, reliable performance and comfortable application experience. With this system, the radiologists and the clinicians can manipulate with 3D images easily, and use the advanced visualization tools to facilitate their work with a PACS display workstation at any time.

  20. Craniosynostosis: prenatal diagnosis by 2D/3D ultrasound, magnetic resonance imaging and computed tomography.

    PubMed

    Helfer, Talita Micheletti; Peixoto, Alberto Borges; Tonni, Gabriele; Araujo Júnior, Edward

    2016-09-01

    Craniosynostosis is defined as the process of premature fusion of one or more of the cranial sutures. It is a common condition that occurs in about 1 to 2,000 live births. Craniosynostosis may be classified in primary or secondary. It is also classified as nonsyndromic or syndromic. According to suture commitment, craniosynostosis may affect a single suture or multiple sutures. There is a wide range of syndromes involving craniosynostosis and the most common are Apert, Pffeifer, Crouzon, Shaethre-Chotzen and Muenke syndromes. The underlying etiology of nonsyndromic craniosynostosis is unknown. Mutations in the fibroblast growth factor (FGF) signalling pathway play a crucial role in the etiology of craniosynostosis syndromes. Prenatal ultrasound`s detection rate of craniosynostosis is low. Nowadays, different methods can be applied for prenatal diagnosis of craniosynostosis, such as two-dimensional (2D) and three-dimensional (3D) ultrasound, magnetic resonance imaging (MRI), computed tomography (CT) scan and, finally, molecular diagnosis. The presence of craniosynostosis may affect the birthing process. Fetuses with craniosynostosis also have higher rates of perinatal complications. In order to avoid the risks of untreated craniosynostosis, children are usually treated surgically soon after postnatal diagnosis.