Science.gov

Sample records for 3d post processing

  1. 3D scientific visualization of reservoir simulation post-processing

    SciTech Connect

    Sousa, M.C.; Miranda-Filho, D.N.

    1994-12-31

    This paper describes a 3D visualization software designed at PETROBRAS and TecGraf/PUC-RJ in Brazil for the analysis of reservoir engineering post-processing data. It offers an advanced functional environment on graphical workstations with intuitive and ergonomic interface. Applications to real reservoir models show the enriching features of the software.

  2. Different post-processing conditions for 3D bioprinted α-tricalcium phosphate scaffolds.

    PubMed

    Bertol, Liciane Sabadin; Schabbach, Rodrigo; Loureiro Dos Santos, Luis Alberto

    2017-09-15

    The development of 3D printing hardware, software and materials has enabled the production of bone substitute scaffolds for tissue engineering. Calcium phosphates cements, such as those based on α-tricalcium phosphate (α-TCP), have recognized properties of osteoinductivity, osteoconductivity and resorbability and can be used to 3D print scaffolds to support and induce tissue formation and be replaced by natural bone. At present, however, the mechanical properties found for 3D printed bone scaffolds are only satisfactory for non-load bearing applications. This study varied the post-processing conditions of the 3D powder printing process of α-TCP cement scaffolds by either immersing the parts into binder, Ringer's solution or phosphoric acid, or by sintering in temperatures ranging from 800 to 1500 °C. The porosity, composition (phase changes), morphology, shrinkage and compressive strength were evaluated. The mechanical strength of the post-processed 3D printed scaffolds increased compared to the green parts and was in the range of the trabecular bone. Although the mechanical properties achieved are still low, the high porosity presented by the scaffolds can potentially result in greater bone ingrowth. The phases present in the scaffolds after the post-processing treatments were calcium-deficient hydroxyapatite, brushite, monetite, and unreacted α-TCP. Due to their chemical composition, the 3D printed scaffolds are expected to be resorbable, osteoinductive, and osteoconductive.

  3. Post-processing of 3D-printed parts using femtosecond and picosecond laser radiation

    NASA Astrophysics Data System (ADS)

    Mingareev, Ilya; Gehlich, Nils; Bonhoff, Tobias; Meiners, Wilhelm; Kelbassa, Ingomar; Biermann, Tim; Richardson, Martin C.

    2014-03-01

    Additive manufacturing, also known as 3D-printing, is a near-net shape manufacturing approach, delivering part geometry that can be considerably affected by various process conditions, heat-induced distortions, solidified melt droplets, partially fused powders, and surface modifications induced by the manufacturing tool motion and processing strategy. High-repetition rate femtosecond and picosecond laser radiation was utilized to improve surface quality of metal parts manufactured by laser additive techniques. Different laser scanning approaches were utilized to increase the ablation efficiency and to reduce the surface roughness while preserving the initial part geometry. We studied post-processing of 3D-shaped parts made of Nickel- and Titanium-base alloys by utilizing Selective Laser Melting (SLM) and Laser Metal Deposition (LMD) as additive manufacturing techniques. Process parameters such as the pulse energy, the number of layers and their spatial separation were varied. Surface processing in several layers was necessary to remove the excessive material, such as individual powder particles, and to reduce the average surface roughness from asdeposited 22-45 μm to a few microns. Due to the ultrafast laser-processing regime and the small heat-affected zone induced in materials, this novel integrated manufacturing approach can be used to post-process parts made of thermally and mechanically sensitive materials, and to attain complex designed shapes with micrometer precision.

  4. Joint Adaptive Pre-processing Resilience and Post-processing Concealment Schemes for 3D Video Transmission

    NASA Astrophysics Data System (ADS)

    El-Shafai, Walid

    2015-03-01

    3D video transmission over erroneous networks is still a considerable issue due to restricted resources and the presence of severe channel errors. Efficiently compressing 3D video with low transmission rate, while maintaining a high quality of received 3D video, is very challenging. Since it is not plausible to re-transmit all the corrupted macro-blocks (MBs) due to real time applications and limited resources. Thus it is mandatory to retrieve the lost MBs at the decoder side using sufficient post-processing schemes, such as error concealment (EC). In this paper, we propose an adaptive multi-mode EC (AMMEC) algorithm at the decoder based on utilizing pre-processing flexible macro-block ordering error resilience (FMO-ER) technique at the encoder; to efficiently conceal the erroneous MBs of intra and inter coded frames of 3D video. Experimental simulation results show that the proposed FMO-ER/AMMEC schemes can significantly improve the objective and subjective 3D video quality.

  5. Detectability of hepatic tumors during 3D post-processed ultrafast cone-beam computed tomography

    NASA Astrophysics Data System (ADS)

    Paul, Jijo; Vogl, Thomas J.; Chacko, Annamma

    2015-10-01

    To evaluate hepatic tumor detection using ultrafast cone-beam computed tomography (UCBCT) cross-sectional and 3D post-processed image datasets. 657 patients were examined using UCBCT during hepatic transarterial chemoembolization (TACE), and data were collected retrospectively from January 2012 to September 2014. Tumor detectability, diagnostic ability, detection accuracy and sensitivity were examined for different hepatic tumors using UCBCT cross-sectional, perfusion blood volume (PBV) and UCBCT-MRI (magnetic resonance imaging) fused image datasets. Appropriate statistical tests were used to compare collected sample data. Fused image data showed the significantly higher (all P  <  0.05) diagnostic ability for hepatic tumors compared to UCBCT or PBV image data. The detectability of small hepatic tumors (<5 mm) was significantly reduced (all P  <  0.05) using UCBCT cross-sectional images compared to MRI or fused image data; however, PBV improved tumor detectability using a color display. Fused image data produced 100% tumor sensitivity due to the simultaneous availability of MRI and UCBCT information during tumor diagnosis. Fused image data produced excellent hepatic tumor sensitivity, detectability and diagnostic ability compared to other datasets assessed. Fused image data is extremely reliable and useful compared to UCBCT cross-sectional or PBV image datasets to depict hepatic tumors during TACE. Partial anatomical visualization on cross-sectional images was compensated by fused image data during tumor diagnosis.

  6. Post-processing methods of rendering and visualizing 3-D reconstructed tomographic images

    SciTech Connect

    Wong, S.T.C.

    1997-02-01

    The purpose of this presentation is to discuss the computer processing techniques of tomographic images, after they have been generated by imaging scanners, for volume visualization. Volume visualization is concerned with the representation, manipulation, and rendering of volumetric data. Since the first digital images were produced from computed tomography (CT) scanners in the mid 1970s, applications of visualization in medicine have expanded dramatically. Today, three-dimensional (3D) medical visualization has expanded from using CT data, the first inherently digital source of 3D medical data, to using data from various medical imaging modalities, including magnetic resonance scanners, positron emission scanners, digital ultrasound, electronic and confocal microscopy, and other medical imaging modalities. We have advanced from rendering anatomy to aid diagnosis and visualize complex anatomic structures to planning and assisting surgery and radiation treatment. New, more accurate and cost-effective procedures for clinical services and biomedical research have become possible by integrating computer graphics technology with medical images. This trend is particularly noticeable in current market-driven health care environment. For example, interventional imaging, image-guided surgery, and stereotactic and visualization techniques are now stemming into surgical practice. In this presentation, we discuss only computer-display-based approaches of volumetric medical visualization. That is, we assume that the display device available is two-dimensional (2D) in nature and all analysis of multidimensional image data is to be carried out via the 2D screen of the device. There are technologies such as holography and virtual reality that do provide a {open_quotes}true 3D screen{close_quotes}. To confine the scope, this presentation will not discuss such approaches.

  7. Parallelization of Program to Optimize Simulated Trajectories (POST3D)

    NASA Technical Reports Server (NTRS)

    Hammond, Dana P.; Korte, John J. (Technical Monitor)

    2001-01-01

    This paper describes the parallelization of the Program to Optimize Simulated Trajectories (POST3D). POST3D uses a gradient-based optimization algorithm that reaches an optimum design point by moving from one design point to the next. The gradient calculations required to complete the optimization process, dominate the computational time and have been parallelized using a Single Program Multiple Data (SPMD) on a distributed memory NUMA (non-uniform memory access) architecture. The Origin2000 was used for the tests presented.

  8. How post-processing by selective thermal reflow can reduce the roughness of 3D lithography in micro-optical lenses

    NASA Astrophysics Data System (ADS)

    Kirchner, Robert; Chidambaram, Nachiappan; Altana, Mirco; Schift, Helmut

    2017-02-01

    Most polymeric refractive micro-optics simultaneously demand ultra-smooth 3D topographies and precise geometry for high optical performance and low stray light. We have established a surface selective smoothening for thermoplastic polymers that does not affect the designed optical geometry. For example, high curvature corners required for a 50 μm tall optical diffuser device were maintained while the surface roughness was reduced to about 10 nm RMS. 3D master structures were fabricated using direct write laser-lithography with two-photon absorption. Master structures were then replicated into poly(methyl methacrylate) through a poly(dimethyl siloxane) intermediate copying step and subsequently smoothed-out by high-energy photon exposure and thermal post-processing. The smoothening results in a lower roughness compared to a direct writing strategy using even about 50 nm vertical discretization steps still enables 10 times faster writing times.

  9. Advanced 3D mesh manipulation in stereolithographic files and post-print processing for the manufacturing of patient-specific vascular flow phantoms

    NASA Astrophysics Data System (ADS)

    O'Hara, Ryan P.; Chand, Arpita; Vidiyala, Sowmya; Arechavala, Stacie M.; Mitsouras, Dimitrios; Rudin, Stephen; Ionita, Ciprian N.

    2016-03-01

    Complex vascular anatomies can cause the failure of image-guided endovascular procedures. 3D printed patient-specific vascular phantoms provide clinicians and medical device companies the ability to preemptively plan surgical treatments, test the likelihood of device success, and determine potential operative setbacks. This research aims to present advanced mesh manipulation techniques of stereolithographic (STL) files segmented from medical imaging and post-print surface optimization to match physiological vascular flow resistance. For phantom design, we developed three mesh manipulation techniques. The first method allows outlet 3D mesh manipulations to merge superfluous vessels into a single junction, decreasing the number of flow outlets and making it feasible to include smaller vessels. Next we introduced Boolean operations to eliminate the need to manually merge mesh layers and eliminate errors of mesh self-intersections that previously occurred. Finally we optimize support addition to preserve the patient anatomical geometry. For post-print surface optimization, we investigated various solutions and methods to remove support material and smooth the inner vessel surface. Solutions of chloroform, alcohol and sodium hydroxide were used to process various phantoms and hydraulic resistance was measured and compared with values reported in literature. The newly mesh manipulation methods decrease the phantom design time by 30 - 80% and allow for rapid development of accurate vascular models. We have created 3D printed vascular models with vessel diameters less than 0.5 mm. The methods presented in this work could lead to shorter design time for patient specific phantoms and better physiological simulations.

  10. TOUGH2Viewer: A post-processing tool for interactive 3D visualization of locally refined unstructured grids for TOUGH2

    NASA Astrophysics Data System (ADS)

    Bonduá, S.; Berry, P.; Bortolotti, V.; Cormio, C.

    2012-09-01

    Within the MAC-GEO research project, funded by Regione Toscana and addressed to the exploitation of high enthalpy geothermal systems, the authors worked on the utilization and customization of the open source numerical simulator TOUGH2, as implemented in the code dedicated to model calibration iTOUGH2. TOUGH2 is one of the most used numerical simulation software for non-isothermal flow of multicomponent, multiphase fluids in one, two and three-dimensional porous and fractured media. Lacking an official Graphical User Interface tool for post-processing operations, several commercial and academic software have been developed to manage and display TOUGH2 input and output data files. Almost all of these tools seem to have limits to visualizing parameter values of the numerical model, work only with a predefined binary version of TOUGH2, and only a few of them can manage locally refined unstructured grids (i.e. Voronoi grids). To overcome these limitations, the authors have developed and tested a dedicated software application (called TOUGH2Viewer) for reading and managing TOUGH2 output files, written in Java and able to provide an interactive 3D view of the numerical model. Several functionalities have been implemented for block query and searching, contour mapping and 3D surface mapping of TOUGH2 primary variables (i.e. pressure, temperature, etc.). TOUGH2Viewer is also able to display 2D and 3D views of mass and heat flow between blocks, for each time step in which the simulation proceeds. The application described in this paper is under development to improve its functionalities; nevertheless the current software release is a valid support tool for post-processing that significantly improves the possibility to inspect the simulated data coming from TOUGH2.

  11. Adirondack Post-Drill (3-D)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This is a 3-D anaglyph showing a microscopic image taken of an area measuring 3 centimeters (1.2 inches) across on the rock called Adirondack. The image was taken at Gusev Crater on the 33rd day of the Mars Exploration Rover Spirit's journey (Feb. 5, 2004), after the rover used its rock abrasion tool to drill into the rock. Debris from the use of the tool is visible to the left of the hole.

  12. Modeling cellular processes in 3D.

    PubMed

    Mogilner, Alex; Odde, David

    2011-12-01

    Recent advances in photonic imaging and fluorescent protein technology offer unprecedented views of molecular space-time dynamics in living cells. At the same time, advances in computing hardware and software enable modeling of ever more complex systems, from global climate to cell division. As modeling and experiment become more closely integrated we must address the issue of modeling cellular processes in 3D. Here, we highlight recent advances related to 3D modeling in cell biology. While some processes require full 3D analysis, we suggest that others are more naturally described in 2D or 1D. Keeping the dimensionality as low as possible reduces computational time and makes models more intuitively comprehensible; however, the ability to test full 3D models will build greater confidence in models generally and remains an important emerging area of cell biological modeling. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Modeling Cellular Processes in 3-D

    PubMed Central

    Mogilner, Alex; Odde, David

    2011-01-01

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

  14. 3-D visualization of geologic structures and processes

    NASA Astrophysics Data System (ADS)

    Pflug, R.; Klein, H.; Ramshorn, Ch.; Genter, M.; Stärk, A.

    Interactive 3-D computer graphics techniques are used to visualize geologic structures and simulated geologic processes. Geometric models that serve as input to 3-D viewing programs are generated from contour maps, from serial sections, or directly from simulation program output. Choice of viewing parameters strongly affects the perception of irregular surfaces. An interactive 3-D rendering program and its graphical user interface provide visualization tools for structural geology, seismic interpretation, and visual post-processing of simulations. Dynamic display of transient ground-water simulations and sedimentary process simulations can visualize processes developing through time.

  15. Method for modeling post-mortem biometric 3D fingerprints

    NASA Astrophysics Data System (ADS)

    Rajeev, Srijith; Shreyas, Kamath K. M.; Agaian, Sos S.

    2016-05-01

    Despite the advancements of fingerprint recognition in 2-D and 3-D domain, authenticating deformed/post-mortem fingerprints continue to be an important challenge. Prior cleansing and reconditioning of the deceased finger is required before acquisition of the fingerprint. The victim's finger needs to be precisely and carefully operated by a medium to record the fingerprint impression. This process may damage the structure of the finger, which subsequently leads to higher false rejection rates. This paper proposes a non-invasive method to perform 3-D deformed/post-mortem finger modeling, which produces a 2-D rolled equivalent fingerprint for automated verification. The presented novel modeling method involves masking, filtering, and unrolling. Computer simulations were conducted on finger models with different depth variations obtained from Flashscan3D LLC. Results illustrate that the modeling scheme provides a viable 2-D fingerprint of deformed models for automated verification. The quality and adaptability of the obtained unrolled 2-D fingerprints were analyzed using NIST fingerprint software. Eventually, the presented method could be extended to other biometric traits such as palm, foot, tongue etc. for security and administrative applications.

  16. A 3-D Look at Post-Tropical Cyclone Hermine

    NASA Image and Video Library

    This 3-D flyby animation of GPM imagery shows Post-Tropical Storm Hermine on Sept. 6. Rain was falling at a rate of over 1.1 inches (27 mm) per hour between the Atlantic coast and Hermine's center ...

  17. 3D integral imaging with optical processing

    NASA Astrophysics Data System (ADS)

    Martínez-Corral, Manuel; Martínez-Cuenca, Raúl; Saavedra, Genaro; Javidi, Bahram

    2008-04-01

    Integral imaging (InI) systems are imaging devices that provide auto-stereoscopic images of 3D intensity objects. Since the birth of this new technology, InI systems have faced satisfactorily many of their initial drawbacks. Basically, two kind of procedures have been used: digital and optical procedures. The "3D Imaging and Display Group" at the University of Valencia, with the essential collaboration of Prof. Javidi, has centered its efforts in the 3D InI with optical processing. Among other achievements, our Group has proposed the annular amplitude modulation for enlargement of the depth of field, dynamic focusing for reduction of the facet-braiding effect, or the TRES and MATRES devices to enlarge the viewing angle.

  18. Process for 3D chip stacking

    DOEpatents

    Malba, Vincent

    1998-01-01

    A manufacturable process for fabricating electrical interconnects which extend from a top surface of an integrated circuit chip to a sidewall of the chip using laser pantography to pattern three dimensional interconnects. The electrical interconnects may be of an L-connect or L-shaped type. The process implements three dimensional (3D) stacking by moving the conventional bond or interface pads on a chip to the sidewall of the chip. Implementation of the process includes: 1) holding individual chips for batch processing, 2) depositing a dielectric passivation layer on the top and sidewalls of the chips, 3) opening vias in the dielectric, 4) forming the interconnects by laser pantography, and 5) removing the chips from the holding means. The process enables low cost manufacturing of chips with bond pads on the sidewalls, which enables stacking for increased performance, reduced space, and higher functional per unit volume.

  19. Process for 3D chip stacking

    DOEpatents

    Malba, V.

    1998-11-10

    A manufacturable process for fabricating electrical interconnects which extend from a top surface of an integrated circuit chip to a sidewall of the chip using laser pantography to pattern three dimensional interconnects. The electrical interconnects may be of an L-connect or L-shaped type. The process implements three dimensional (3D) stacking by moving the conventional bond or interface pads on a chip to the sidewall of the chip. Implementation of the process includes: (1) holding individual chips for batch processing, (2) depositing a dielectric passivation layer on the top and sidewalls of the chips, (3) opening vias in the dielectric, (4) forming the interconnects by laser pantography, and (5) removing the chips from the holding means. The process enables low cost manufacturing of chips with bond pads on the sidewalls, which enables stacking for increased performance, reduced space, and higher functional per unit volume. 3 figs.

  20. 3-D analysis of grain selection process

    NASA Astrophysics Data System (ADS)

    Arao, Tomoka; Esaka, Hisao; Shinozuka, Kei

    2012-07-01

    It is known that the grain selection plays an important role in the manufacturing process for turbine blades. There are some analytical or numerical models to treat the grain selection. However, the detailed mechanism of grain selection in 3-D is still uncertain. Therefore, an experimental research work using Al-Cu alloy has been carried out in order to understand the grain selection in 3-D.A mold made by Al2O3 was heated to 600 °C ( = liquids temperature of the alloy) and was set on a water-colded copper chill plate. Molten Al-20 wt%Cu alloy was cast into the mold and unidirectional solidified ingot was prepared. The size of ingot was approximately phi25×65H mm. To obtain the thermal history, 4 thermocouples were placed in the mold. It is confirmed that the alloy solidified unidirectionally from bottom to top. Solidified structure on a longitudinal cross section was observed and unidirectional solidification up to 40 mm was ensured. EBSD analysis has been performed on horizontal cross section at an interval of ca.200 μm. These observations were carried out 7-5 mm from the bottom surface. Crystallographic orientation of primary Al phase and size of solidified grains were characterized. A large solidified grain, the crystallographic orientation of which is approximately <101> along heat flow direction, is observed near the lowest cross section. The area of <101> grain decreased as solidification proceeded. On the other hand, it is found that the area of <001> grain increased.

  1. 3D seismic image processing for interpretation

    NASA Astrophysics Data System (ADS)

    Wu, Xinming

    Extracting fault, unconformity, and horizon surfaces from a seismic image is useful for interpretation of geologic structures and stratigraphic features. Although interpretation of these surfaces has been automated to some extent by others, significant manual effort is still required for extracting each type of these geologic surfaces. I propose methods to automatically extract all the fault, unconformity, and horizon surfaces from a 3D seismic image. To a large degree, these methods just involve image processing or array processing which is achieved by efficiently solving partial differential equations. For fault interpretation, I propose a linked data structure, which is simpler than triangle or quad meshes, to represent a fault surface. In this simple data structure, each sample of a fault corresponds to exactly one image sample. Using this linked data structure, I extract complete and intersecting fault surfaces without holes from 3D seismic images. I use the same structure in subsequent processing to estimate fault slip vectors. I further propose two methods, using precomputed fault surfaces and slips, to undo faulting in seismic images by simultaneously moving fault blocks and faults themselves. For unconformity interpretation, I first propose a new method to compute a unconformity likelihood image that highlights both the termination areas and the corresponding parallel unconformities and correlative conformities. I then extract unconformity surfaces from the likelihood image and use these surfaces as constraints to more accurately estimate seismic normal vectors that are discontinuous near the unconformities. Finally, I use the estimated normal vectors and use the unconformities as constraints to compute a flattened image, in which seismic reflectors are all flat and vertical gaps correspond to the unconformities. Horizon extraction is straightforward after computing a map of image flattening; we can first extract horizontal slices in the flattened space

  2. Symbolic processing methods for 3D visual processing

    NASA Astrophysics Data System (ADS)

    Tedder, Maurice; Hall, Ernest L.

    2001-10-01

    The purpose of this paper is to describe a theory that defines an open method for solving 3D visual data processing and artificial intelligence problems that is independent of hardware or software implementation. The goal of the theory is to generalize and abstract the process of 3D visual processing so that the method can be applied to a wide variety of 3D visual processing problems. Once the theory is described a heuristic derivation is given. Symbolic processing methods can be generalized into an abstract model composed of eight basic components. The symbolic processing model components are: input data; input data interface; symbolic data library; symbolic data environment space; relationship matrix; symbolic logic driver; output data interface and output data. An obstacle detection and avoidance experiment was constructed to demonstrate the symbolic processing method. The results of the robot obstacle avoidance experiment demonstrated that the mobile robot could successfully navigate the obstacle course using symbolic processing methods for the control software. The significance of the symbolic processing approach is that the method arrived at a solution by using a more formal quantifiable process. Some of the practical applications for this theory are: 3D object recognition, obstacle avoidance, and intelligent robot control.

  3. MeshLab: 3D triangular meshes processing and editing

    NASA Astrophysics Data System (ADS)

    Cignoni, P.; Callieri, M.; Corsini, M.; Dellepiane, M.; Ganovelli, F.; Ranzuglia, G.

    2017-09-01

    MeshLab processes and edits 3D triangular meshes. It includes tools for editing, cleaning, healing, inspecting, rendering, texturing and converting meshes, and offers features for processing raw data produced by 3D digitization tools and devices and for preparing models for 3D printing.

  4. Laser processing in 3D diamond detectors

    NASA Astrophysics Data System (ADS)

    Murphy, S. A.; Booth, M.; Li, L.; Oh, A.; Salter, P.; Sun, B.; Whitehead, D.; Zadoroshnyj, A.

    2017-02-01

    A technique for electrode production within diamond using a femtosecond laser system is described. Diagnosis tests to quantify the stress, the diamond to graphite ratio, and the resistivity of these electrodes are discussed. A 3D electronic grade single crystal diamond detector produced using this technique is shown, and the electrodes have a resistivity of O(1 Ω cm). An improvement to the technique through the use of an adaptive wavefront shows a reduction of the diamond to graphite ratio, and smaller, higher quality electrodes were manufactured.

  5. Superplot3d: an open source GUI tool for 3d trajectory visualisation and elementary processing.

    PubMed

    Whitehorn, Luke J; Hawkes, Frances M; Dublon, Ian An

    2013-09-30

    When acquiring simple three-dimensional (3d) trajectory data it is common to accumulate large coordinate data sets. In order to examine integrity and consistency of object tracking, it is often necessary to rapidly visualise these data. Ordinarily, to achieve this the user must either execute 3d plotting functions in a numerical computing environment or manually inspect data in two dimensions, plotting each individual axis.Superplot3d is an open source MATLAB script which takes tab delineated Cartesian data points in the form x, y, z and time and generates an instant visualization of the object's trajectory in free-rotational three dimensions. Whole trajectories may be instantly presented, allowing for rapid inspection. Executable from the MATLAB command line (or deployable as a compiled standalone application) superplot3d also provides simple GUI controls to obtain rudimentary trajectory information, allow specific visualization of trajectory sections and perform elementary processing.Superplot3d thus provides a framework for non-programmers and programmers alike, to recreate recently acquired 3d object trajectories in rotatable 3d space. It is intended, via the use of a preference driven menu to be flexible and work with output from multiple tracking software systems. Source code and accompanying GUIDE .fig files are provided for deployment and further development.

  6. Remote Collaborative 3D Printing - Process Investigation

    DTIC Science & Technology

    2016-04-01

    were able to be completely processed end-to-end from an NMCI computer, due to the lack of available slicing software and limitations on connecting NMCI...cleat model were successfully printed. The Ohio-replacement submarine was not able be processed for printing with the available tools and software on...2 2.3. Files printed from Model Libraries and other sources ......................................................... 2 3. SOFTWARE , TOOLS, AND

  7. Identifying positioning-based attacks against 3D printed objects and the 3D printing process

    NASA Astrophysics Data System (ADS)

    Straub, Jeremy

    2017-05-01

    Zeltmann, et al. demonstrated that structural integrity and other quality damage to objects can be caused by changing its position on a 3D printer's build plate. On some printers, for example, object surfaces and support members may be stronger when oriented parallel to the X or Y axis. The challenge presented by the need to assure 3D printed object orientation is that this can be altered in numerous places throughout the system. This paper considers attack scenarios and discusses where attacks that change printing orientation can occur in the process. An imaging-based solution to combat this problem is presented.

  8. Low cost 3D scanning process using digital image processing

    NASA Astrophysics Data System (ADS)

    Aguilar, David; Romero, Carlos; Martínez, Fernando

    2017-02-01

    This paper shows the design and building of a low cost 3D scanner, able to digitize solid objects through contactless data acquisition, using active object reflection. 3D scanners are used in different applications such as: science, engineering, entertainment, etc; these are classified in: contact scanners and contactless ones, where the last ones are often the most used but they are expensive. This low-cost prototype is done through a vertical scanning of the object using a fixed camera and a mobile horizontal laser light, which is deformed depending on the 3-dimensional surface of the solid. Using digital image processing an analysis of the deformation detected by the camera was done; it allows determining the 3D coordinates using triangulation. The obtained information is processed by a Matlab script, which gives to the user a point cloud corresponding to each horizontal scanning done. The obtained results show an acceptable quality and significant details of digitalized objects, making this prototype (built on LEGO Mindstorms NXT kit) a versatile and cheap tool, which can be used for many applications, mainly by engineering students.

  9. OPC for edge post structures using chrome-less phase shifting mask in 3-D memory

    NASA Astrophysics Data System (ADS)

    Chen, Yung-Tin; Lee, M. T.

    2005-11-01

    Matrix Semiconductor have successfully implemented chrome-less phase shifting mask to their 0.13μm half pitch, 3D memory circuit process using 0.7NA KrF photolithography. The K1 factor is 0.37. OPC for post structures at the edge of memory array presents a special challenge for 3-D memory circuits. As 3-D memory circuits are stacked vertically, the topography also accumulates to the top of memory layers, thus resulting in reduced process margin due to "peeling off" of edge posts. Ruled based and model based OPC for edge posts are studied in this paper. A simple ruled based OPC is developed to compensate the size difference between the posts at array center and the ones at array edge. A manufacturing oriented OPC strategy is used to gain optimum process windows. The wafer printing results from ruled based OPC are compared to the model prediction from commercial lithography software. Discrepancy between wafer printing results and model prediction using thin film mask approximation is reported. A new model based OPC method for chrome-less PSM in the application to post structures is proposed from this study.

  10. A 3-D SAR approach to IFSAR processing

    SciTech Connect

    DOERRY,ARMIN W.; BICKEL,DOUGLAS L.

    2000-03-01

    Interferometric SAR (IFSAR) can be shown to be a special case of 3-D SAR image formation. In fact, traditional IFSAR processing results in the equivalent of merely a super-resolved, under-sampled, 3-D SAR image. However, when approached as a 3-D SAR problem, a number of IFSAR properties and anomalies are easily explained. For example, IFSAR decorrelation with height is merely ordinary migration in 3-D SAR. Consequently, treating IFSAR as a 3-D SAR problem allows insight and development of proper motion compensation techniques and image formation operations to facilitate optimal height estimation. Furthermore, multiple antenna phase centers and baselines are easily incorporated into this formulation, providing essentially a sparse array in the elevation dimension. This paper shows the Polar Format image formation algorithm extended to 3 dimensions, and then proceeds to apply it to the IFSAR collection geometry. This suggests a more optimal reordering of the traditional IFSAR processing steps.

  11. 3-D AVO processing: Evolution of a processing sequence

    SciTech Connect

    Jones, I.F.; Mandache, V.; Campbell, S.; Lancaster, S.

    1994-12-31

    The use of seismic amplitudes has long been recognized as an important aid in the location of hydrocarbons. More recently, this has been extended to include the study of the variations of amplitude as the shot-receiver offset is changed. Here the authors present a case history outlining the development of an AVO processing sequence for application to 3D data sets, including the use of prestack 3D target oriented time migration. AVO attributes at different points in the processing sequence are compared. Successive improvements in the AVO response (both in the RO and gradient seismic sections) demonstrate the advantage of focusing diffraction energy in the CMP gathers prior to estimation of the AVO response. The effect of surface-related multiple energy and its removal is also addressed, comparing a conventional FK demultiple approach with that of the parabolic tau-p transform. Measures of statistical reliability of the AVO results are considered with comparisons of statistical measures being made at various stages of the imaging and multiple suppression. For example, the correlation coefficient associated with least-squares fitting shows an improvement for certain horizons after in-line migration, and further improvement after subsequent interpolation and cross-line migration.

  12. GLOBE 3D : an new 3D toolset for Geoscience data processing

    NASA Astrophysics Data System (ADS)

    Sinquin, Jean-Marc; Sorribas, Jordi; Diviacco, Paolo; Baeye, Matthias; Quemener, Gael

    2013-04-01

    Within EUROFLEETS project, and linked to EMODNET and GEOSEAS european projects, GLOBE (GLobal Oceanographic Bathymetry Explorer) is an innovative and generic software combining all necessary functionalities for cruise preparation, for collection, linking, processing and display of scientific data acquired during sea cruises, and for export of data and information to the main marine data centres and networks. The first version was delivered by the end of 2012 and was dedicated to MBES (Multi Beam Echo Sounder) data processing, but is designed to accept further functionalities such as image and video. It can be used onboard during the survey to get a quick view of acquired data, or later, to re-process data with accurate environmental data. Technically, the concept of the software relies on Eclipse RCP for the hosted client, Java and Nasa World Wind for the 3D views. The version shown at EGU will present several key items : - 3D vizualisation : DTM multi-layers from EmodNET, WaterColumn echogram, Seismic lines, ... - Bathymetry Plug-In : manual and automatic data cleaning, - Photo/Video Plug-In - Navigation - WMS/WFS interfaces.

  13. Overview of 3D laser materials processing concepts

    NASA Astrophysics Data System (ADS)

    Tsoukantas, George; Salonitis, Konstantinos; Stavropoulos, Panagiotis; Chryssolouris, George

    2003-04-01

    The term of 3D laser processing has been used so far to describe a group of different three-dimensional laser processing concepts. At each of these concepts the 3D aspect refers to a different manipulation of one or more laser beams, as to process and/or produce three-dimensional geometries by performing material removal, welding or heat treating. The most important concepts are focused mainly in laser machining and laser welding processes by incorporating one or two laser beams simultaneously. This paper overviews a number of these concepts that have been developed in research or industrial level, along with their advantages, drawbacks and fields of application.

  14. Imaging 3D strain field monitoring during hydraulic fracturing processes

    NASA Astrophysics Data System (ADS)

    Chen, Rongzhang; Zaghloul, Mohamed A. S.; Yan, Aidong; Li, Shuo; Lu, Guanyi; Ames, Brandon C.; Zolfaghari, Navid; Bunger, Andrew P.; Li, Ming-Jun; Chen, Kevin P.

    2016-05-01

    In this paper, we present a distributed fiber optic sensing scheme to study 3D strain fields inside concrete cubes during hydraulic fracturing process. Optical fibers embedded in concrete were used to monitor 3D strain field build-up with external hydraulic pressures. High spatial resolution strain fields were interrogated by the in-fiber Rayleigh backscattering with 1-cm spatial resolution using optical frequency domain reflectometry. The fiber optics sensor scheme presented in this paper provides scientists and engineers a unique laboratory tool to understand the hydraulic fracturing processes in various rock formations and its impacts to environments.

  15. 3-D laser patterning process utilizing horizontal and vertical patterning

    DOEpatents

    Malba, Vincent; Bernhardt, Anthony F.

    2000-01-01

    A process which vastly improves the 3-D patterning capability of laser pantography (computer controlled laser direct-write patterning). The process uses commercially available electrodeposited photoresist (EDPR) to pattern 3-D surfaces. The EDPR covers the surface of a metal layer conformally, coating the vertical as well as horizontal surfaces. A laser pantograph then patterns the EDPR, which is subsequently developed in a standard, commercially available developer, leaving patterned trench areas in the EDPR. The metal layer thereunder is now exposed in the trench areas and masked in others, and thereafter can be etched to form the desired pattern (subtractive process), or can be plated with metal (additive process), followed by a resist stripping, and removal of the remaining field metal (additive process). This improved laser pantograph process is simpler, faster, move manufacturable, and requires no micro-machining.

  16. 3D Printed Surgical Instruments: The Design and Fabrication Process.

    PubMed

    George, Mitchell; Aroom, Kevin R; Hawes, Harvey G; Gill, Brijesh S; Love, Joseph

    2017-01-01

    3D printing is an additive manufacturing process allowing the creation of solid objects directly from a digital file. We believe recent advances in additive manufacturing may be applicable to surgical instrument design. This study investigates the feasibility, design and fabrication process of usable 3D printed surgical instruments. The computer-aided design package SolidWorks (Dassault Systemes SolidWorks Corp., Waltham MA) was used to design a surgical set including hemostats, needle driver, scalpel handle, retractors and forceps. These designs were then printed on a selective laser sintering (SLS) Sinterstation HiQ (3D Systems, Rock Hill SC) using DuraForm EX plastic. The final printed products were evaluated by practicing general surgeons for ergonomic functionality and performance, this included simulated surgery and inguinal hernia repairs on human cadavers. Improvements were identified and addressed by adjusting design and build metrics. Repeated manufacturing processes and redesigns led to the creation of multiple functional and fully reproducible surgical sets utilizing the user feedback of surgeons. Iterative cycles including design, production and testing took an average of 3 days. Each surgical set was built using the SLS Sinterstation HiQ with an average build time of 6 h per set. Functional 3D printed surgical instruments are feasible. Advantages compared to traditional manufacturing methods include no increase in cost for increased complexity, accelerated design to production times and surgeon specific modifications.

  17. Motion Rehab AVE 3D: A VR-based exergame for post-stroke rehabilitation.

    PubMed

    Trombetta, Mateus; Bazzanello Henrique, Patrícia Paula; Brum, Manoela Rogofski; Colussi, Eliane Lucia; De Marchi, Ana Carolina Bertoletti; Rieder, Rafael

    2017-11-01

    Recent researches about games for post-stroke rehabilitation have been increasing, focusing in upper limb, lower limb and balance situations, and showing good experiences and results. With this in mind, this paper presents Motion Rehab AVE 3D, a serious game for post-stroke rehabilitation of patients with mild stroke. The aim is offer a new technology in order to assist the traditional therapy and motivate the patient to execute his/her rehabilitation program, under health professional supervision. The game was developed with Unity game engine, supporting Kinect motion sensing input device and display devices like Smart TV 3D and Oculus Rift. It contemplates six activities considering exercises in a tridimensional space: flexion, abduction, shoulder adduction, horizontal shoulder adduction and abduction, elbow extension, wrist extension, knee flexion, and hip flexion and abduction. Motion Rehab AVE 3D also report about hits and errors to the physiotherapist evaluate the patient's progress. A pilot study with 10 healthy participants (61-75 years old) tested one of the game levels. They experienced the 3D user interface in third-person. Our initial goal was to map a basic and comfortable setup of equipment in order to adopt later. All the participants (100%) classified the interaction process as interesting and amazing for the age, presenting a good acceptance. Our evaluation showed that the game could be used as a useful tool to motivate the patients during rehabilitation sessions. Next step is to evaluate its effectiveness for stroke patients, in order to verify if the interface and game exercises contribute into the motor rehabilitation treatment progress. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. The 3D model control of image processing

    NASA Technical Reports Server (NTRS)

    Nguyen, An H.; Stark, Lawrence

    1989-01-01

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

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

    NASA Astrophysics Data System (ADS)

    Milkereit, B.; Bohlen, T.

    2001-12-01

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

  20. Forensic print extraction using 3D technology and its processing

    NASA Astrophysics Data System (ADS)

    Rajeev, Srijith; Shreyas, Kamath K. M.; Panetta, Karen; Agaian, Sos S.

    2017-05-01

    Biometric evidence plays a crucial role in criminal scene analysis. Forensic prints can be extracted from any solid surface such as firearms, doorknobs, carpets and mugs. Prints such as fingerprints, palm prints, footprints and lip-prints can be classified into patent, latent, and three-dimensional plastic prints. Traditionally, law enforcement officers capture these forensic traits using an electronic device or extract them manually, and save the data electronically using special scanners. The reliability and accuracy of the method depends on the ability of the officer or the electronic device to extract and analyze the data. Furthermore, the 2-D acquisition and processing system is laborious and cumbersome. This can lead to the increase in false positive and true negative rates in print matching. In this paper, a method and system to extract forensic prints from any surface, irrespective of its shape, is presented. First, a suitable 3-D camera is used to capture images of the forensic print, and then the 3-D image is processed and unwrapped to obtain 2-D equivalent biometric prints. Computer simulations demonstrate the effectiveness of using 3-D technology for biometric matching of fingerprints, palm prints, and lip-prints. This system can be further extended to other biometric and non-biometric modalities.

  1. Fatigue resistance of unnotched and post impact(+/- 30 deg/0 deg) 3-D braided composites

    NASA Technical Reports Server (NTRS)

    Portanova, Marc A.

    1994-01-01

    The fatigue resistance of a multiaxial braided (3-D) graphite/expoxy composite in both unnotched and post impacted conditions has been evaluated. The material tested is a (+/- 30/0 deg) multiaxial braid constructed from AS4/12K tow graphite fibers and British Petroleum E905L epoxy resin. These materials were braided as dry preforms and the epoxy was added using a resin transfer molding process (RTM). The unnotched and post-impact specimens were tested in compression-compression fatigue at 10 Hz with a stress ratio of R=10. The unnotched tension-tension fatigue specimens were tested at S Hz with a stress ration of R=0.1. Damage initiation and growth was documented through the application of radiography and ultrasonic through transmission (C-scans). Visible inspection of surface and edge damage was also noted to describe the initiation and progression of damage in these materials. The mechanisms leading to damage initiation were established and failure modes were determined. Stiffness and strength degradation were measured as a function of applied cycles. These 3-D braided composite results were compared to strain levels currently used to design primary structure in commercial aircraft composite components made from prepreg tape and autoclave cured.

  2. Validation of image processing tools for 3-D fluorescence microscopy.

    PubMed

    Dieterlen, Alain; Xu, Chengqi; Gramain, Marie-Pierre; Haeberlé, Olivier; Colicchio, Bruno; Cudel, Christophe; Jacquey, Serge; Ginglinger, Emanuelle; Jung, Georges; Jeandidier, Eric

    2002-04-01

    3-D optical fluorescent microscopy becomes nowadays an efficient tool for volumic investigation of living biological samples. Using optical sectioning technique, a stack of 2-D images is obtained. However, due to the nature of the system optical transfer function and non-optimal experimental conditions, acquired raw data usually suffer from some distortions. In order to carry out biological analysis, raw data have to be restored by deconvolution. The system identification by the point-spread function is useful to obtain the knowledge of the actual system and experimental parameters, which is necessary to restore raw data. It is furthermore helpful to precise the experimental protocol. In order to facilitate the use of image processing techniques, a multi-platform-compatible software package called VIEW3D has been developed. It integrates a set of tools for the analysis of fluorescence images from 3-D wide-field or confocal microscopy. A number of regularisation parameters for data restoration are determined automatically. Common geometrical measurements and morphological descriptors of fluorescent sites are also implemented to facilitate the characterisation of biological samples. An example of this method concerning cytogenetics is presented.

  3. Platform for 3D inline process control in additive manufacturing

    NASA Astrophysics Data System (ADS)

    Preissler, Marc; Zhang, Chen; Rosenberger, Maik; Notni, Gunther

    2017-06-01

    3D - Inline - Process - Control is getting more attention in any fields of manufacturing processes to increase productivity and quality. Sensor systems are necessary to capture the currently process status and are basement for Inline-Process- Control. The presented work is a possibility to get inline information's about the additive manufacturing process Fused Filament Fabrication. The requirement is the ability to manipulate the machine code to get free field of view to the topside of the object after every manufactured layer. The adaptable platform layout makes possible to create different approaches for inline process control. One approach is the single camera layout from bird view to get 2,5D information's about the manufactured object and the other one is the active stereoscopic camera layout with pattern projection. Both approaches are showing a possibility to get information's of the manufactured object in process. Additional this cases allow a view inside the manufactured object and defects can be located. Deviations in the manufacturing process can be corrected and relevant parameters can be adapted during slicing process to increase the manufacturing quality.

  4. Imaging fault zones using 3D seismic image processing techniques

    NASA Astrophysics Data System (ADS)

    Iacopini, David; Butler, Rob; Purves, Steve

    2013-04-01

    Significant advances in structural analysis of deep water structure, salt tectonic and extensional rift basin come from the descriptions of fault system geometries imaged in 3D seismic data. However, even where seismic data are excellent, in most cases the trajectory of thrust faults is highly conjectural and still significant uncertainty exists as to the patterns of deformation that develop between the main faults segments, and even of the fault architectures themselves. Moreover structural interpretations that conventionally define faults by breaks and apparent offsets of seismic reflectors are commonly conditioned by a narrow range of theoretical models of fault behavior. For example, almost all interpretations of thrust geometries on seismic data rely on theoretical "end-member" behaviors where concepts as strain localization or multilayer mechanics are simply avoided. Yet analogue outcrop studies confirm that such descriptions are commonly unsatisfactory and incomplete. In order to fill these gaps and improve the 3D visualization of deformation in the subsurface, seismic attribute methods are developed here in conjunction with conventional mapping of reflector amplitudes (Marfurt & Chopra, 2007)). These signal processing techniques recently developed and applied especially by the oil industry use variations in the amplitude and phase of the seismic wavelet. These seismic attributes improve the signal interpretation and are calculated and applied to the entire 3D seismic dataset. In this contribution we will show 3D seismic examples of fault structures from gravity-driven deep-water thrust structures and extensional basin systems to indicate how 3D seismic image processing methods can not only build better the geometrical interpretations of the faults but also begin to map both strain and damage through amplitude/phase properties of the seismic signal. This is done by quantifying and delineating the short-range anomalies on the intensity of reflector amplitudes

  5. Hybrid 3D printing by bridging micro/nano processes

    NASA Astrophysics Data System (ADS)

    Yoon, Hae-Sung; Jang, Ki-Hwan; Kim, Eunseob; Lee, Hyun-Taek; Ahn, Sung-Hoon

    2017-06-01

    A hybrid 3D printing process was developed for multiple-material/freeform nano-scale manufacturing. The process consisted of aerodynamically focused nanoparticle (AFN) printing, micro-machining, focused ion beam milling, and spin-coating. Theoretical and experimental investigations were carried out to improve the compatibility of each of the processes, enabling bridging of various different techniques. The resulting hybrid process could address the limitations of individual processes, enabling improved process scaling and dimensional degrees of freedom, without losing the advantages of the existing processes. The minimum structure width can be reduced to 50 nm using undercut structures. In addition, AFN printing employs particle impact for adhesion, and various inorganic materials are suitable for printing, including metals and functional ceramics. Using the developed system, we fabricated bi-material cantilevers for applications as a thermal actuator. The mechanical and thermal properties of the structure were investigated using an in situ measurement system, and irregular thermal phenomena due to the fabrication process were analyzed. We expect that this work will lead to improvements in the area of customized nano-scale manufacturing, as well as further improvements in manufacturing technology by combining different fabrication techniques.

  6. Integrated 3D printing and corona poling process of PVDF piezoelectric films for pressure sensor application

    NASA Astrophysics Data System (ADS)

    Kim, Hoejin; Torres, Fernando; Wu, Yanyu; Villagran, Dino; Lin, Yirong; Tseng, Tzu-Liang(Bill

    2017-08-01

    This paper presents a novel process to fabricate piezoelectric films from polyvinylidene fluoride (PVDF) polymer using integrated fused deposition modeling (FDM) 3D printing and corona poling technique. Corona poling is one of many effective poling processes that has received attention to activate PVDF as a piezoelectric responsive material. The corona poling process occurs when a PVDF polymer is exposed to a high electric field created and controlled through an electrically charged needle and a grid electrode under heating environment. FDM 3D printing has seen extensive progress in fabricating thermoplastic materials and structures, including PVDF. However, post processing techniques such as poling is needed to align the dipoles in order to gain piezoelectric properties. To further simplify the piezoelectric sensors and structures fabrication process, this paper proposes an integrated 3D printing process with corona poling to fabricate piezoelectric PVDF sensors without post poling process. This proposed process, named ‘Integrated 3D Printing and Corona poling process’ (IPC), uses the 3D printer’s nozzle and heating bed as anode and cathode, respectively, to create poling electric fields in a controlled heating environment. The nozzle travels along the programmed path with fixed distance between nozzle tip and sample’s top surface. Simultaneously, the electric field between the nozzle and bottom heating pad promotes the alignment of dipole moment of PVDF molecular chains. The crystalline phase transformation and output current generated by printed samples under different electric fields in this process were characterized by a Fourier transform infrared spectroscopy and through fatigue load frame. It is demonstrated that piezoelectric PVDF films with enhanced β-phase percentage can be fabricated using the IPC process. In addition, mechanical properties of printed PVDF was investigated by tensile testing. It is expected to expand the use of additive

  7. Fundamental characterization of soft matter 3D printing processes

    NASA Astrophysics Data System (ADS)

    Migler, Kalman; Seppala, Jonathan; Davis, Chelsea; Hillgartner, Kaitlyn

    In fused filament fabrication (FFF), a material extrusion 3D printing method, thermoplastic filament is extruded though a rastering nozzle on the previous layer. The resulting strength of the FFF produced part is limited by the strength of the weld between each layer. While numerous factors can affect the weld strength, the temperature of the extrudate and the previous layer dictate the amount of interdiffusion and thus the weld strength. Temperature measurements were performed using forward looking infrared imaging. Interdiffusion estimates were calculated from temperature profiles, normalized using horizontal shift factors from offline rheological measurements of the neat polymer. Weld strength was measured directly by Mode III Fracture using a simplified geometry limiting the measurement to a single weld. Since the processing conditions are known aprioi this approach provides the data needed to estimate the final build strength at time of design. The resulting agreement between interdiffusion estimates and weld strength for a range of printing conditions are discussed.

  8. 3D-MID and process monitoring for microjoining applications

    NASA Astrophysics Data System (ADS)

    Ostendorf, Andreas; Specker, Wilhelm; Stallmach, Matthias; Zeadan, Jeihad

    2003-07-01

    Nd:YAG solid-state lasers have been integrated in many seam welding applications. They provide a good ability of integration into existing manufacturing sequences and allow its easy automation. Appropriate process monitoring systems are needed to decrease necessary user intervention, to ensure a high machine availability and to realize a zero defect production. In the electronics industry, laser spot welding techniques using pulsed Nd:YAG-lasers have been established in mass production applications, for example in manufacturing of electron gun components for TV monitor tubes over the last 25 years. They require different strategies and methods for process monitoring systems. Apart from these integrated laser spot welding applications, there is a current demand for new technologies to join micro components onto 3-dimensional (3-D) circuit substrates and to connect electrical plugs. In recent years, laser spot joining techniques have emerged as a viable option for packaging electrical and mechanical microparts, such as surface mounted devices (SMDs) and casings. Under most conditions, laser spot welding provides more durability as well as thermal and mechanical stability compared to traditional packaging techniques, such as simultaneous soldering. Additionally, under less ideal conditions, the packaging quality can be inconsistent, resulting in the need for optimization and monitoring of the weld parameters under different conditions. In order to achieve a stable process during packaging of electrical components despite their weak absorption of laser radiation and different surface qualities, a process monitoring system should be needed.

  9. 3D Simulation Modeling of the Tooth Wear Process

    PubMed Central

    Dai, Ning; Hu, Jian; Liu, Hao

    2015-01-01

    Severe tooth wear is the most common non-caries dental disease, and it can seriously affect oral health. Studying the tooth wear process is time-consuming and difficult, and technological tools are frequently lacking. This paper presents a novel method of digital simulation modeling that represents a new way to study tooth wear. First, a feature extraction algorithm is used to obtain anatomical feature points of the tooth without attrition. Second, after the alignment of non-attrition areas, the initial homogeneous surface is generated by means of the RBF (Radial Basic Function) implicit surface and then deformed to the final homogeneous by the contraction and bounding algorithm. Finally, the method of bilinear interpolation based on Laplacian coordinates between tooth with attrition and without attrition is used to inversely reconstruct the sequence of changes of the 3D tooth morphology during gradual tooth wear process. This method can also be used to generate a process simulation of nonlinear tooth wear by means of fitting an attrition curve to the statistical data of attrition index in a certain region. The effectiveness and efficiency of the attrition simulation algorithm are verified through experimental simulation. PMID:26241942

  10. 3D Simulation Modeling of the Tooth Wear Process.

    PubMed

    Dai, Ning; Hu, Jian; Liu, Hao

    2015-01-01

    Severe tooth wear is the most common non-caries dental disease, and it can seriously affect oral health. Studying the tooth wear process is time-consuming and difficult, and technological tools are frequently lacking. This paper presents a novel method of digital simulation modeling that represents a new way to study tooth wear. First, a feature extraction algorithm is used to obtain anatomical feature points of the tooth without attrition. Second, after the alignment of non-attrition areas, the initial homogeneous surface is generated by means of the RBF (Radial Basic Function) implicit surface and then deformed to the final homogeneous by the contraction and bounding algorithm. Finally, the method of bilinear interpolation based on Laplacian coordinates between tooth with attrition and without attrition is used to inversely reconstruct the sequence of changes of the 3D tooth morphology during gradual tooth wear process. This method can also be used to generate a process simulation of nonlinear tooth wear by means of fitting an attrition curve to the statistical data of attrition index in a certain region. The effectiveness and efficiency of the attrition simulation algorithm are verified through experimental simulation.

  11. Contactless operating table control based on 3D image processing.

    PubMed

    Schröder, Stephan; Loftfield, Nina; Langmann, Benjamin; Frank, Klaus; Reithmeier, Eduard

    2014-01-01

    Interaction with mobile consumer devices leads to a higher acceptance and affinity of persons to natural user interfaces and perceptional interaction possibilities. New interaction modalities become accessible and are capable to improve human machine interaction even in complex and high risk environments, like the operation room. Here, manifold medical disciplines cause a great variety of procedures and thus staff and equipment. One universal challenge is to meet the sterility requirements, for which common contact-afflicted remote interfaces always pose a potential risk causing a hazard for the process. The proposed operating table control system overcomes this process risk and thus improves the system usability significantly. The 3D sensor system, the Microsoft Kinect, captures the motion of the user, allowing a touchless manipulation of an operating table. Three gestures enable the user to select, activate and manipulate all segments of the motorised system in a safe and intuitive way. The gesture dynamics are synchronised with the table movement. In a usability study, 15 participants evaluated the system with a system usability score by Broke of 79. This states a high potential for implementation and acceptance in interventional environments. In the near future, even processes with higher risks could be controlled with the proposed interface, while interfaces become safer and more direct.

  12. Comparison of post-contrast 3D-T1-MPRAGE, 3D-T1-SPACE and 3D-T2-FLAIR MR images in evaluation of meningeal abnormalities at 3-T MRI.

    PubMed

    Jeevanandham, Balaji; Kalyanpur, Tejas; Gupta, Prashant; Cherian, Mathew

    2017-06-01

    This study was to assess the usefulness of newer three-dimensional (3D)-T1 sampling perfection with application optimized contrast using different flip-angle evolutions (SPACE) and 3D-T2 fluid-attenuated inversion recovery (FLAIR) sequences in evaluation of meningeal abnormalities. 78 patients who presented with high suspicion of meningeal abnormalities were evaluated using post-contrast 3D-T2-FLAIR, 3D-T1 magnetization-prepared rapid gradient-echo (MPRAGE) and 3D-T1-SPACE sequences. The images were evaluated independently by two radiologists for cortical gyral, sulcal space, basal cisterns and dural enhancement. The diagnoses were confirmed by further investigations including histopathology. Post-contrast 3D-T1-SPACE and 3D-T2-FLAIR images yielded significantly more information than MPRAGE images (p < 0.05 for both SPACE and FLAIR images) in detection of meningeal abnormalities. SPACE images best demonstrated abnormalities in dural and sulcal spaces, whereas FLAIR was useful for basal cisterns enhancement. Both SPACE and FLAIR performed equally well in detection of gyral enhancement. In all 10 patients, where both SPACE and T2-FLAIR images failed to demonstrate any abnormality, further analysis was also negative. The 3D-T1-SPACE sequence best demonstrated abnormalities in dural and sulcal spaces, whereas FLAIR was useful for abnormalities in basal cisterns. Both SPACE and FLAIR performed holds good for detection of gyral enhancement. Post-contrast SPACE and FLAIR sequences are superior to the MPRAGE sequence for evaluation of meningeal abnormalities and when used in combination have the maximum sensitivity for leptomeningeal abnormalities. The negative-predictive value is nearly 100%, where no leptomeningeal abnormality was detected on these sequences. Advances in knowledge: Post-contrast 3D-T1-SPACE and 3D-T2-FLAIR images are more useful than 3D-T1-MPRAGE images in evaluation of meningeal abnormalities.

  13. Enhanced osteogenic activity of poly(ester urea) scaffolds using facile post-3D printing peptide functionalization strategies.

    PubMed

    Li, Shan; Xu, Yanyi; Yu, Jiayi; Becker, Matthew L

    2017-10-01

    Additive manufacturing has the potential to revolutionize regenerative medicine, but the harsh thermal or photochemical conditions during the 3D printing process limit the inclusion of drugs, growth factors and other biologics within the resulting scaffolds. Functionalization strategies that enable specific placement of bioactive species on the surface of 3D printed structures following the printing process afford a promising approach to sidestep the harsh conditions and incorporate these valuable bioactive molecules with precise control over concentration. Herein, resorbable polymer scaffolds were prepared from propargyl functionalized L-phenylalanine-based poly(ester urea)s (PEUs). Osteogenic growth peptide (OGP) or bone morphogenic protein-2 (BMP-2) peptides were immobilized on PEU scaffolds through surface available propargyl groups via copper-catalyzed azide alkyne cycloaddition (CuAAC) post 3D printing. The presence of either OGP or BMP-2 significantly enhanced hMSCs osteogenic differentiation compared to unfunctionalized scaffolds. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Autostereoscopic 3D visualization and image processing system for neurosurgery.

    PubMed

    Meyer, Tobias; Kuß, Julia; Uhlemann, Falk; Wagner, Stefan; Kirsch, Matthias; Sobottka, Stephan B; Steinmeier, Ralf; Schackert, Gabriele; Morgenstern, Ute

    2013-06-01

    A demonstrator system for planning neurosurgical procedures was developed based on commercial hardware and software. The system combines an easy-to-use environment for surgical planning with high-end visualization and the opportunity to analyze data sets for research purposes. The demonstrator system is based on the software AMIRA. Specific algorithms for segmentation, elastic registration, and visualization have been implemented and adapted to the clinical workflow. Modules from AMIRA and the image processing library Insight Segmentation and Registration Toolkit (ITK) can be combined to solve various image processing tasks. Customized modules tailored to specific clinical problems can easily be implemented using the AMIRA application programming interface and a self-developed framework for ITK filters. Visualization is done via autostereoscopic displays, which provide a 3D impression without viewing aids. A Spaceball device allows a comfortable, intuitive way of navigation in the data sets. Via an interface to a neurosurgical navigation system, the demonstrator system can be used intraoperatively. The precision, applicability, and benefit of the demonstrator system for planning of neurosurgical interventions and for neurosurgical research were successfully evaluated by neurosurgeons using phantom and patient data sets.

  15. 3D geometrical modelling of post-foliation deformations in metamorphic terrains (Syros, Cyclades, Greece)

    NASA Astrophysics Data System (ADS)

    Philippon, Mélody; Le Carlier de Veslud, Christian; Gueydan, Frédéric; Brun, Jean-Pierre; Caumon, Guillaume

    2015-09-01

    Superposed to ductile syn-metamorphic deformations, post-foliation deformations affect metamorphic units during their exhumation. Understanding the role of such deformations in the structuration of metamorphic units is key for understanding the tectonic evolution of convergence zones. We characterize post-foliations deformations using 3D modelling which is a first-order tool to describe complex geological structures, but a challenging task where based only on surface data. We propose a modelling procedure that combines fast draft models (interpolation of orientation data), with more complex ones where the structural context is better understood (implicit modelling), allowing us to build a 3D geometrical model of Syros Island blueschists (Cyclades), based on field data. With our approach, the 3D model is able to capture the complex present-day geometry of the island, mainly controlled by the superposition of three types of post-metamorphic deformations affecting the original metamorphic pile: i) a top-to-South ramp-flat extensional system that dominates the overall island structure, ii) large-scale folding of the metamorphic units associated with ramp-flat extensional system, and iii) steeply-dipping normal faults trending dominantly NNW-SSE and EW. The 3D surfaces produced by this method match outcrop data, are geologically consistent, and provide reasonable estimates of geological structures in poorly constrained areas.

  16. Induction Heating Process: 3D Modeling and Optimisation

    NASA Astrophysics Data System (ADS)

    Naar, R.; Bay, F.

    2011-05-01

    An increasing number of problems in mechanics and physics involves multiphysics coupled problems. Among these problems, we can often find electromagnetic coupled problems. Electromagnetic couplings may be involved through the use of direct or induced currents for thermal purposes—in order to generate heat inside a work piece in order to get either a prescribed temperature field or some given mechanical or metallurgical properties through an accurate control of temperature evolution with respect to time-, or for solid or fluid mechanics purposes—in order to create magnetic forces such as in fluid mechanics (electromagnetic stirring,…) or solid mechanics (magnetoforming,…). Induction heat treatment processes is therefore quite difficult to control; trying for instance to minimize distortions generated by such a process is not easy. In order to achieve these objectives, we have developed a computational tool which includes an optimsation stage. A 3D finite element modeling tool for local quenching after induction heating processes has already been developed in our laboratory. The modeling of such a multiphysics coupled process needs taking into account electromagnetic, thermal, mechanical and metallurgical phenomenon—as well as their mutual interactions during the whole process: heating and quenching. The model developed is based on Maxwell equations, heat transfer equation, mechanical equilibrium computations, Johnson-Mehl-Avrami and Koistinen-Marburger laws. All these equations and laws may be coupled but some coupling may be neglected. In our study, we will also focus on induction heating process aiming at optimising the Heat Affected Zone (HAZ). Thus problem is formalized as an optimization problem—minimizing a cost function which measures the difference between computed and optimal temperatures—along with some constraints on process parameters. The optimization algorithms may be of two kinds—either zero-order or first-order algorithms. First

  17. A monolithic 3D integrated nanomagnetic co-processing unit

    NASA Astrophysics Data System (ADS)

    Becherer, M.; Breitkreutz-v. Gamm, S.; Eichwald, I.; Žiemys, G.; Kiermaier, J.; Csaba, G.; Schmitt-Landsiedel, D.

    2016-01-01

    As CMOS scaling becomes more and more challenging there is strong impetus for beyond CMOS device research to add new functionality to ICs. In this article, a promising technology with non-volatile ferromagnetic computing states - the so-called Perpendicular Nanomagnetic Logic (pNML) - is reviewed. After introducing the 2D planar implementation of NML with magnetization perpendicular to the surface, the path to monolithically 3D integrated systems is discussed. Instead of CMOS substitution, additional functionality is added by a co-processor architecture as a prospective back-end-of-line (BEOL) process, where the computing elements are clocked by a soft-magnetic on-chip inductor. The unconventional computation in the ferromagnetic domain can lead to highly dense computing structures without leakage currents, attojoule dissipation per bit operation and data-throughputs comparable to state-of-the-art high-performance CMOS CPUs. In appropriate applications and with specialized computing architectures they might even circumvent the bottleneck of time-consuming memory access, as computation is inherently performed with non-volatile computing states.

  18. Dynamics of electron emission in double photoionization processes near the krypton 3d threshold

    NASA Astrophysics Data System (ADS)

    Penent, F.; Sheinerman, S.; Andric, L.; Lablanquie, P.; Palaudoux, J.; Becker, U.; Braune, M.; Viefhaus, J.; Eland, J. H. D.

    2008-02-01

    Two-electron emission following photoabsorption near the Kr 3d threshold is investigated both experimentally and theoretically. On the experimental side, electron/electron coincidences using a magnetic bottle time-of-flight spectrometer allow us to observe the complete double photo ionization (DPI) continua of selected Kr2+ final states, and to see how these continua are affected by resonant processes in the vicinity of the Kr 3d threshold. The analysis is based on a quantum mechanical approach that takes into account the contribution of three different processes: (A) Auger decay of the inner 3d vacancy with the associated post-collision interaction (PCI) effects, (B) capture of slow photoelectrons into discrete states followed by valence multiplet decay (VMD) of the excited ionic states and (C) valence shell DPI. The dominant process for each Kr2+(4p-2) final state is the photoionization of the inner shell followed by Auger decay of the 3d vacancies. Moreover, for the 4p-2(3P) and 4p-2(1D) final ionic states an important contribution comes from the processes of slow photoelectron capture followed by VMD as well as from double ionization of the outer shell involving also VMD.

  19. An integrated 3D log processing optimization system for small sawmills in central Appalachia

    Treesearch

    Wenshu Lin; Jingxin. Wang

    2013-01-01

    An integrated 3D log processing optimization system was developed to perform 3D log generation, opening face determination, headrig log sawing simulation, fl itch edging and trimming simulation, cant resawing, and lumber grading. A circular cross-section model, together with 3D modeling techniques, was used to reconstruct 3D virtual logs. Internal log defects (knots)...

  20. Progresses in 3D integral imaging with optical processing

    NASA Astrophysics Data System (ADS)

    Martínez-Corral, Manuel; Martínez-Cuenca, Raúl; Saavedra, Genaro; Navarro, Héctor; Pons, Amparo; Javidi, Bahram

    2008-11-01

    Integral imaging is a promising technique for the acquisition and auto-stereoscopic display of 3D scenes with full parallax and without the need of any additional devices like special glasses. First suggested by Lippmann in the beginning of the 20th century, integral imaging is based in the intersection of ray cones emitted by a collection of 2D elemental images which store the 3D information of the scene. This paper is devoted to the study, from the ray optics point of view, of the optical effects and interaction with the observer of integral imaging systems.

  1. High Accuracy 3D Processing of Satellite Imagery

    NASA Technical Reports Server (NTRS)

    Gruen, A.; Zhang, L.; Kocaman, S.

    2007-01-01

    Automatic DSM/DTM generation reproduces not only general features, but also detailed features of the terrain relief. Height accuracy of around 1 pixel in cooperative terrain. RMSE values of 1.3-1.5 m (1.0-2.0 pixels) for IKONOS and RMSE values of 2.9-4.6 m (0.5-1.0 pixels) for SPOT5 HRS. For 3D city modeling, the manual and semi-automatic feature extraction capability of SAT-PP provides a good basis. The tools of SAT-PP allowed the stereo-measurements of points on the roofs in order to generate a 3D city model with CCM The results show that building models with main roof structures can be successfully extracted by HRSI. As expected, with Quickbird more details are visible.

  2. TAURUS: an interactive post-processor for the analysis codes NIKE3D, DYNA3D, TACO3D, and GEMINI. Revision 1

    SciTech Connect

    Brown, B.E.; Hallquist, J.O.

    1984-05-01

    This report provides a user's manual for the post-processor, TAURUS. TAURUS reads the binary plot files generated by the two and three dimensional finite element codes currently used at LLNL and plots contours, time histories, and deformed shapes. Contours of a large number of quantities may be plotted on meshes consisting of plate, shell, and solid type elements. TAURUS can compute a variety of strain measures, reaction forces along constrained boundaries, and momentum. TAURUS is operational on the CRAY-1, 7600, and VAX computers.

  3. TAURUS: an interactive post-processor for the analysis codes NIKE3D, DYNA3D, TACO3D, and GEMINI

    SciTech Connect

    Brown, B.E.; Hallquist, J.O.

    1982-07-01

    This report provides a user's manual for the post-processor, TAURUS. TAURUS reads the binary plot files generated by the three-dimensional finite element codes currently used at LLNL and plots contours, time histories, and deformed shapes. Contours of a large number of quantities may be plotted on meshes consisting of plate, shell, and solid type elements. TAURUS can compute a variety of strain measures, reaction forces along constrained boundaries, and momentum. TAURUS is operational on the CRAY-1 and 7600 computers.

  4. 3-D Velocity Measurement of Natural Convection Using Image Processing

    NASA Astrophysics Data System (ADS)

    Shinoki, Masatoshi; Ozawa, Mamoru; Okada, Toshifumi; Kimura, Ichiro

    This paper describes quantitative three-dimensional measurement method for flow field of a rotating Rayleigh-Benard convection in a cylindrical cell heated below and cooled above. A correlation method for two-dimensional measurement was well advanced to a spatio-temporal correlation method. Erroneous vectors, often appeared in the correlation method, was successfully removed using Hopfield neural network. As a result, calculated 3-D velocity vector distribution well corresponded to the observed temperature distribution. Consequently, the simultaneous three-dimensional measurement system for temperature and flow field was developed.

  5. Infrared imaging of the polymer 3D-printing process

    NASA Astrophysics Data System (ADS)

    Dinwiddie, Ralph B.; Kunc, Vlastimil; Lindal, John M.; Post, Brian; Smith, Rachel J.; Love, Lonnie; Duty, Chad E.

    2014-05-01

    Both mid-wave and long-wave IR cameras are used to measure various temperature profiles in thermoplastic parts as they are printed. Two significantly different 3D-printers are used in this study. The first is a small scale commercially available Solidoodle 3 printer, which prints parts with layer thicknesses on the order of 125μm. The second printer used is a "Big Area Additive Manufacturing" (BAAM) 3D-printer developed at Oak Ridge National Laboratory. The BAAM prints parts with a layer thicknesses of 4.06 mm. Of particular interest is the temperature of the previously deposited layer as the new hot layer is about to be extruded onto it. The two layers are expected have a stronger bond if the temperature of the substrate layer is above the glass transition temperature. This paper describes the measurement technique and results for a study of temperature decay and substrate layer temperature for ABS thermoplastic with and without the addition of chopped carbon fibers.

  6. Visualization of early post-implantation mouse embryogenesis using 3D imaging modality (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Hsu, Chih-Wei; Le, Henry H.; Li-Villarreal, Nanbing; Piazza, Victor G.; Kalaga, Sowmya; Dickinson, Mary E.

    2017-02-01

    Hemodynamic force is vital to cardiovascular remodeling in the early post-implantation mouse embryo. Here, we present work using microCT and lightsheet microscopy to establish the critical sequence of developmental events required for forming functional vasculature and circulation in the embryo, yolk sac, and placenta in the context of normal and impaired flow. A flow impaired model, Mlc2a+/- will be used to determine how hemodynamic force affects the specific events during embryonic development and vascular remodeling between the 4 and 29-somite stage using microCT. We have recently established high-resolution methods for the generation of 3D image volumes from the whole embryo within the deciduum (Hsu et al., in revision). This method enables the careful characterization of 3D images of vitelline and umbilical vessel remodeling to define how poor blood flow impacts both vitelline and umbilical vessel remodeling. Novel lightsheet live imaging techniques will be used to determine the consequence of impaired blood flow on yolk sac vasculature remodeling and formation of umbilical vessels using transgenic reporters: Flk-myr::mCherry, Flk1-H2B::YFP, or ɛGlobin-GFP. High-resolution 3D imaging of fixed and ScaleA2-cleared whole mount embryos labeled with Ki67 and Caspase3 will also be performed using lightsheet microscopy to quantify the proliferation and apoptotic indexes of early post-implanted embryos and yolk sac. This multi-modality approach is aimed at revealing further information about the cellular mechanisms required for proper vessel remodeling and the initial stages in placentation during early post-implantation development.

  7. Robotic extrusion processes for direct ink writing of 3D conductive polyaniline structures

    NASA Astrophysics Data System (ADS)

    Holness, F. Benjamin; Price, Aaron D.

    2016-04-01

    The intractable nature of intrinsically conductive polymers (ICP) leads to practical limitations in the fabrication of ICP-based transducers having complex three-dimensional geometries. Conventional ICP device fabrication processes have focused primarily on thin-film deposition techniques; therefore this study explores novel additive manufacturing processes specifically developed for ICP with the ultimate goal of increasing the functionality of ICP sensors and actuators. Herein we employ automated polymer paste extrusion processes for the direct ink writing of 3D conductive polyaniline (PANI) structures. Realization of these structures is enabled through a modified fused filament fabrication delta robot equipped with an integrated polymer paste extruder. This unique robot-controlled additive manufacturing platform is capable of fabricating high-resolution 3D conductive PANI and has been utilized to produce structures with a minimum feature size of 1.5 mm. The required processability of PANI is achieved by means of a counter-ion induced thermal doping method. Using this method, a viscous paste is formulated as the extrudate and a thermo-chemical treatment is applied post extrusion to finalize the complexation.

  8. Development of the Improving Process for the 3D Printed Structure

    PubMed Central

    Takagishi, Kensuke; Umezu, Shinjiro

    2017-01-01

    The authors focus on the Fused Deposition Modeling (FDM) 3D printer because the FDM 3D printer can print the utility resin material. It can print with low cost and therefore it is the most suitable for home 3D printer. The FDM 3D printer has the problem that it produces layer grooves on the surface of the 3D printed structure. Therefore the authors developed the 3D-Chemical Melting Finishing (3D-CMF) for removing layer grooves. In this method, a pen-style device is filled with a chemical able to dissolve the materials used for building 3D printed structures. By controlling the behavior of this pen-style device, the convex parts of layer grooves on the surface of the 3D printed structure are dissolved, which, in turn, fills the concave parts. In this study it proves the superiority of the 3D-CMF than conventional processing for the 3D printed structure. It proves utilizing the evaluation of the safety, selectively and stability. It confirms the improving of the 3D-CMF and it is confirmed utilizing the data of the surface roughness precision and the observation of the internal state and the evaluation of the mechanical characteristics. PMID:28054558

  9. Development of the Improving Process for the 3D Printed Structure.

    PubMed

    Takagishi, Kensuke; Umezu, Shinjiro

    2017-01-05

    The authors focus on the Fused Deposition Modeling (FDM) 3D printer because the FDM 3D printer can print the utility resin material. It can print with low cost and therefore it is the most suitable for home 3D printer. The FDM 3D printer has the problem that it produces layer grooves on the surface of the 3D printed structure. Therefore the authors developed the 3D-Chemical Melting Finishing (3D-CMF) for removing layer grooves. In this method, a pen-style device is filled with a chemical able to dissolve the materials used for building 3D printed structures. By controlling the behavior of this pen-style device, the convex parts of layer grooves on the surface of the 3D printed structure are dissolved, which, in turn, fills the concave parts. In this study it proves the superiority of the 3D-CMF than conventional processing for the 3D printed structure. It proves utilizing the evaluation of the safety, selectively and stability. It confirms the improving of the 3D-CMF and it is confirmed utilizing the data of the surface roughness precision and the observation of the internal state and the evaluation of the mechanical characteristics.

  10. Development of the Improving Process for the 3D Printed Structure

    NASA Astrophysics Data System (ADS)

    Takagishi, Kensuke; Umezu, Shinjiro

    2017-01-01

    The authors focus on the Fused Deposition Modeling (FDM) 3D printer because the FDM 3D printer can print the utility resin material. It can print with low cost and therefore it is the most suitable for home 3D printer. The FDM 3D printer has the problem that it produces layer grooves on the surface of the 3D printed structure. Therefore the authors developed the 3D-Chemical Melting Finishing (3D-CMF) for removing layer grooves. In this method, a pen-style device is filled with a chemical able to dissolve the materials used for building 3D printed structures. By controlling the behavior of this pen-style device, the convex parts of layer grooves on the surface of the 3D printed structure are dissolved, which, in turn, fills the concave parts. In this study it proves the superiority of the 3D-CMF than conventional processing for the 3D printed structure. It proves utilizing the evaluation of the safety, selectively and stability. It confirms the improving of the 3D-CMF and it is confirmed utilizing the data of the surface roughness precision and the observation of the internal state and the evaluation of the mechanical characteristics.

  11. 3D Vision on Mars: Stereo processing and visualizations for NASA and ESA rover missions

    NASA Astrophysics Data System (ADS)

    Huber, Ben

    2016-07-01

    Three dimensional (3D) vision processing is an essential component of planetary rover mission planning and scientific data analysis. Standard ground vision processing products are digital terrain maps, panoramas, and virtual views of the environment. Such processing is currently developed for the PanCam instrument of ESA's ExoMars Rover mission by the PanCam 3D Vision Team under JOANNEUM RESEARCH coordination. Camera calibration, quality estimation of the expected results and the interfaces to other mission elements such as operations planning, rover navigation system and global Mars mapping are a specific focus of the current work. The main goals of the 3D Vision team in this context are: instrument design support & calibration processing: Development of 3D vision functionality Visualization: development of a 3D visualization tool for scientific data analysis. 3D reconstructions from stereo image data during the mission Support for 3D scientific exploitation to characterize the overall landscape geomorphology, processes, and the nature of the geologic record using the reconstructed 3D models. The developed processing framework PRoViP establishes an extensible framework for 3D vision processing in planetary robotic missions. Examples of processing products and capabilities are: Digital Terrain Models, Ortho images, 3D meshes, occlusion, solar illumination-, slope-, roughness-, and hazard-maps. Another important processing capability is the fusion of rover and orbiter based images with the support of multiple missions and sensors (e.g. MSL Mastcam stereo processing). For 3D visualization a tool called PRo3D has been developed to analyze and directly interpret digital outcrop models. Stereo image products derived from Mars rover data can be rendered in PRo3D, enabling the user to zoom, rotate and translate the generated 3D outcrop models. Interpretations can be digitized directly onto the 3D surface, and simple measurements of the outcrop and sedimentary features

  12. In-process 3D assessment of micromoulding features

    NASA Astrophysics Data System (ADS)

    Whiteside, B. R.; Spares, R.; Coates, P. D.

    2006-04-01

    Micro injection moulding (micromoulding) technology has recently emerged as a viable manufacturing route for polymer, metal and ceramic components with micro-scale features and surface textures. With a cycle time for production of a single component of just a few seconds, the proces offers the capability for mass production of microscale devices at a low marginal cost. However, the extreme stresses, strain rates and temperature gradients characteristic of the process have the consequence that a slight fluctuation in material properties or moulding conditions can have a significant impact on the dimensional or structural properties of the resulting component and in-line process monitoring is highly desirable. This paper describes the development of an in-process, high speed 3-dimensional measurement system for evaluation of every component manufactured during the process. A high speed camera and microscope lens coupled with a linear stage are used to create a stack of images which are subsequently processed using extended depth of field techniques to form a virtual 3-dimensional contour of the component. This data can then be used to visually verify the quality of the moulding on-screen or standard machine vision algorithms can be employed to allow fully automated quality inspection and filtering of sub-standard products. Good results have been obtained for a range of materials and geometries and measurement accuracy has been verified through comparison with data obtained using a Wyko NT1100 white light interferometer.

  13. HERO - A 3D general relativistic radiative post-processor for accretion discs around black holes

    NASA Astrophysics Data System (ADS)

    Zhu, Yucong; Narayan, Ramesh; Sadowski, Aleksander; Psaltis, Dimitrios

    2015-08-01

    HERO (Hybrid Evaluator for Radiative Objects) is a 3D general relativistic radiative transfer code which has been tailored to the problem of analysing radiation from simulations of relativistic accretion discs around black holes. HERO is designed to be used as a post-processor. Given some fixed fluid structure for the disc (i.e. density and velocity as a function of position from a hydrodynamic or magnetohydrodynamic simulation), the code obtains a self-consistent solution for the radiation field and for the gas temperatures using the condition of radiative equilibrium. The novel aspect of HERO is that it combines two techniques: (1) a short-characteristics (SC) solver that quickly converges to a self-consistent disc temperature and radiation field, with (2) a long-characteristics (LC) solver that provides a more accurate solution for the radiation near the photosphere and in the optically thin regions. By combining these two techniques, we gain both the computational speed of SC and the high accuracy of LC. We present tests of HERO on a range of 1D, 2D, and 3D problems in flat space and show that the results agree well with both analytical and benchmark solutions. We also test the ability of the code to handle relativistic problems in curved space. Finally, we discuss the important topic of ray defects, a major limitation of the SC method, and describe our strategy for minimizing the induced error.

  14. Image processing and 3D visualization in forensic pathologic examination

    NASA Astrophysics Data System (ADS)

    Oliver, William R.; Altschuler, Bruce R.

    1996-02-01

    The use of image processing is becoming increasingly important in the evaluation of violent crime. While much work has been done in the use of these techniques for forensic purposes outside of forensic pathology, its use in the pathologic examination of wounding has been limited. We are investigating the use of image processing and three-dimensional visualization in the analysis of patterned injuries and tissue damage. While image processing will never replace classical understanding and interpretation of how injuries develop and evolve, it can be a useful tool in helping an observer notice features in an image, may help provide correlation of surface to deep tissue injury, and provide a mechanism for the development of a metric for analyzing how likely it may be that a given object may have caused a given wound. We are also exploring methods of acquiring three-dimensional data for such measurements, which is the subject of a second paper.

  15. 3D Simulation and Validation of Tube Piercing Process

    NASA Astrophysics Data System (ADS)

    Ceretti, Elisabetta; Giardini, Claudio; Attanasio, Aldo

    2007-05-01

    In many cases the development of analytical or simulative models of actual production processes can help in improving the product quality furnishing defect-free parts. In particular, when tube piercing processes are referring to, the main problem that can arise is the low quality of the internal tube surface. This type of defect cannot be eliminated during the successive production phases so compromising the final part quality. It is possible to overcome this problem by placing in the correct position the internal plug which defines the internal tube diameter. This position greatly depends on where the tube material begins to break due the acting internal stresses. This phenomenon is called Mannesmann effect. The farther the plug from the Mannesmann cone formation, the higher the oxidation of the internal tube surface. On the contrary the closer the plug, the higher the wear of the plug. In actual practice an on-line control of the position of the Mannesmann cone is impossible to be implemented. In the past, the Authors have developed a model to help the production line technicians in determining where to place the plug. This model was a two dimensional representation of the actual phenomenon, and it has already been proved to correctly represent the actual tube behavior since it was validated by comparing its results with experiments. Using the results of a wide simulation campaign, a neural network was trained and now it is used as an on-line plug position definition support. In the present paper the results obtained using a fully three dimensional model of the process are reported. This model will allow to confirm some simplifying assumption made in the 2D model definition and to study the tube behavior when it reaches and moves on the plug, too. Some comparisons with practical evidences are reported.

  16. Parallel processing for efficient 3D slope stability modelling

    NASA Astrophysics Data System (ADS)

    Marchesini, Ivan; Mergili, Martin; Alvioli, Massimiliano; Metz, Markus; Schneider-Muntau, Barbara; Rossi, Mauro; Guzzetti, Fausto

    2014-05-01

    We test the performance of the GIS-based, three-dimensional slope stability model r.slope.stability. The model was developed as a C- and python-based raster module of the GRASS GIS software. It considers the three-dimensional geometry of the sliding surface, adopting a modification of the model proposed by Hovland (1977), and revised and extended by Xie and co-workers (2006). Given a terrain elevation map and a set of relevant thematic layers, the model evaluates the stability of slopes for a large number of randomly selected potential slip surfaces, ellipsoidal or truncated in shape. Any single raster cell may be intersected by multiple sliding surfaces, each associated with a value of the factor of safety, FS. For each pixel, the minimum value of FS and the depth of the associated slip surface are stored. This information is used to obtain a spatial overview of the potentially unstable slopes in the study area. We test the model in the Collazzone area, Umbria, central Italy, an area known to be susceptible to landslides of different type and size. Availability of a comprehensive and detailed landslide inventory map allowed for a critical evaluation of the model results. The r.slope.stability code automatically splits the study area into a defined number of tiles, with proper overlap in order to provide the same statistical significance for the entire study area. The tiles are then processed in parallel by a given number of processors, exploiting a multi-purpose computing environment at CNR IRPI, Perugia. The map of the FS is obtained collecting the individual results, taking the minimum values on the overlapping cells. This procedure significantly reduces the processing time. We show how the gain in terms of processing time depends on the tile dimensions and on the number of cores.

  17. Visualizing the process of interaction in a 3D environment

    NASA Astrophysics Data System (ADS)

    Vaidya, Vivek; Suryanarayanan, Srikanth; Krishnan, Kajoli; Mullick, Rakesh

    2007-03-01

    As the imaging modalities used in medicine transition to increasingly three-dimensional data the question of how best to interact with and analyze this data becomes ever more pressing. Immersive virtual reality systems seem to hold promise in tackling this, but how individuals learn and interact in these environments is not fully understood. Here we will attempt to show some methods in which user interaction in a virtual reality environment can be visualized and how this can allow us to gain greater insight into the process of interaction/learning in these systems. Also explored is the possibility of using this method to improve understanding and management of ergonomic issues within an interface.

  18. To select the best tool for generating 3D maintenance data and to set the detailed process for obtaining the 3D maintenance data

    NASA Astrophysics Data System (ADS)

    Prashanth, B. N.; Roy, Kingshuk

    2017-07-01

    Three Dimensional (3D) maintenance data provides a link between design and technical documentation creating interactive 3D graphical training and maintenance material. It becomes difficult for an operator to always go through huge paper manuals or come running to the computer for doing maintenance of a machine which makes the maintenance work fatigue. Above being the case, a 3D animation makes maintenance work very simple since, there is no language barrier. The research deals with the generation of 3D maintenance data of any given machine. The best tool for obtaining the 3D maintenance is selected and the tool is analyzed. Using the same tool, a detailed process for extracting the 3D maintenance data for any machine is set. This project aims at selecting the best tool for obtaining 3D maintenance data and to select the detailed process for obtaining 3D maintenance data. 3D maintenance reduces use of big volumes of manuals which creates human errors and makes the work of an operator fatiguing. Hence 3-D maintenance would help in training and maintenance and would increase productivity. 3Dvia when compared with Cortona 3D and Deep Exploration proves to be better than them. 3Dvia is good in data translation and it has the best renderings compared to the other two 3D maintenance software. 3Dvia is very user friendly and it has various options for creating 3D animations. Its Interactive Electronic Technical Publication (IETP) integration is also better than the other two software. Hence 3Dvia proves to be the best software for obtaining 3D maintenance data of any machine.

  19. Rethinking Design Process: Using 3D Digital Models as an Interface in Collaborative Session

    ERIC Educational Resources Information Center

    Ding, Suining

    2008-01-01

    This paper describes a pilot study for an alternative design process by integrating a designer-user collaborative session with digital models. The collaborative session took place in a 3D AutoCAD class for a real world project. The 3D models served as an interface for designer-user collaboration during the design process. Students not only learned…

  20. Rethinking Design Process: Using 3D Digital Models as an Interface in Collaborative Session

    ERIC Educational Resources Information Center

    Ding, Suining

    2008-01-01

    This paper describes a pilot study for an alternative design process by integrating a designer-user collaborative session with digital models. The collaborative session took place in a 3D AutoCAD class for a real world project. The 3D models served as an interface for designer-user collaboration during the design process. Students not only learned…

  1. Fatigue resistance of unnotched and post impact(+/- 30 deg/0 deg) 3-D braided composites. Final report

    SciTech Connect

    Portanova, M.A.

    1994-01-01

    The fatigue resistance of a multiaxial braided (3-D) graphite/expoxy composite in both unnotched and post impacted conditions has been evaluated. The material tested is a (+/- 30/0 deg) multiaxial braid constructed from AS4/12K tow graphite fibers and British Petroleum E905L epoxy resin. These materials were braided as dry preforms and the epoxy was added using a resin transfer molding process (RTM). The unnotched and post-impact specimens were tested in compression-compression fatigue at 10 Hz with a stress ratio of R=10. The unnotched tension-tension fatigue specimens were tested at S Hz with a stress ration of R=0.1. Damage initiation and growth was documented through the application of radiography and ultrasonic through transmission (C-scans). Visible inspection of surface and edge damage was also noted to describe the initiation and progression of damage in these materials. The mechanisms leading to damage initiation were established and failure modes were determined. Stiffness and strength degradation were measured as a function of applied cycles. These 3-D braided composite results were compared to strain levels currently used to design primary structure in commercial aircraft composite components made from prepreg tape and autoclave cured.

  2. Laser processes and analytics for high power 3D battery materials

    NASA Astrophysics Data System (ADS)

    Pfleging, W.; Zheng, Y.; Mangang, M.; Bruns, M.; Smyrek, P.

    2016-03-01

    Laser processes for cutting, modification and structuring of energy storage materials such as electrodes, separator materials and current collectors have a great potential in order to minimize the fabrication costs and to increase the performance and operational lifetime of high power lithium-ion-batteries applicable for stand-alone electric energy storage devices and electric vehicles. Laser direct patterning of battery materials enable a rather new technical approach in order to adjust 3D surface architectures and porosity of composite electrode materials such as LiCoO2, LiMn2O4, LiFePO4, Li(NiMnCo)O2, and Silicon. The architecture design, the increase of active surface area, and the porosity of electrodes or separator layers can be controlled by laser processes and it was shown that a huge impact on electrolyte wetting, lithium-ion diffusion kinetics, cell life-time and cycling stability can be achieved. In general, the ultrafast laser processing can be used for precise surface texturing of battery materials. Nevertheless, regarding cost-efficient production also nanosecond laser material processing can be successfully applied for selected types of energy storage materials. A new concept for an advanced battery manufacturing including laser materials processing is presented. For developing an optimized 3D architecture for high power composite thick film electrodes electrochemical analytics and post mortem analytics using laser-induced breakdown spectroscopy were performed. Based on mapping of lithium in composite electrodes, an analytical approach for studying chemical degradation in structured and unstructured lithium-ion batteries will be presented.

  3. 3-D Seismic Experimentation and Advanced Processing/Inversion Development for Investigations of the Shallow Subsurface

    SciTech Connect

    Levander, Alan R.

    2004-12-01

    Under ER63662, 3-D Seismic Experimentation and Advanced Processing/Inversion Development for Investigations of the Shallow Subsurface, we have completed a number of subprojects associated with the Hill Air Force Base (HAFB) high resolution 3-D reflection/tomography dataset.

  4. Highly Stretchable and UV Curable Elastomers for Digital Light Processing Based 3D Printing.

    PubMed

    Patel, Dinesh K; Sakhaei, Amir Hosein; Layani, Michael; Zhang, Biao; Ge, Qi; Magdassi, Shlomo

    2017-04-01

    Stretchable UV-curable (SUV) elastomers can be stretched by up to 1100% and are suitable for digital-light-processing (DLP)-based 3D-printing technology. DLP printing of these SUV elastomers enables the direct creation of highly deformable complex 3D hollow structures such as balloons, soft actuators, grippers, and buckyball electronical switches.

  5. Optimized data processing for an optical 3D sensor based on flying triangulation

    NASA Astrophysics Data System (ADS)

    Ettl, Svenja; Arold, Oliver; Häusler, Gerd; Gurov, Igor; Volkov, Mikhail

    2013-05-01

    We present data processing methods for an optical 3D sensor based on the measurement principle "Flying Triangulation". The principle enables a motion-robust acquisition of the 3D shape of even complex objects: A hand-held sensor is freely guided around the object while real-time feedback of the measurement progress is delivered during the captioning. Although of high precision, the resulting 3D data usually may exhibit some weaknesses: e.g. outliers might be present and the data size might be too large. We describe the measurement principle and the data processing and conclude with measurement results.

  6. A 3D bioprinting exemplar of the consequences of the regulatory requirements on customized processes.

    PubMed

    Hourd, Paul; Medcalf, Nicholas; Segal, Joel; Williams, David J

    2015-01-01

    Computer-aided 3D printing approaches to the industrial production of customized 3D functional living constructs for restoration of tissue and organ function face significant regulatory challenges. Using the manufacture of a customized, 3D-bioprinted nasal implant as a well-informed but hypothetical exemplar, we examine how these products might be regulated. Existing EU and USA regulatory frameworks do not account for the differences between 3D printing and conventional manufacturing methods or the ability to create individual customized products using mechanized rather than craft approaches. Already subject to extensive regulatory control, issues related to control of the computer-aided design to manufacture process and the associated software system chain present additional scientific and regulatory challenges for manufacturers of these complex 3D-bioprinted advanced combination products.

  7. HEROIC: 3D general relativistic radiative post-processor with comptonization for black hole accretion discs

    NASA Astrophysics Data System (ADS)

    Narayan, Ramesh; Zhu, Yucong; Psaltis, Dimitrios; Saḑowski, Aleksander

    2016-03-01

    We describe Hybrid Evaluator for Radiative Objects Including Comptonization (HEROIC), an upgraded version of the relativistic radiative post-processor code HERO described in a previous paper, but which now Includes Comptonization. HEROIC models Comptonization via the Kompaneets equation, using a quadratic approximation for the source function in a short characteristics radiation solver. It employs a simple form of accelerated lambda iteration to handle regions of high scattering opacity. In addition to solving for the radiation field, HEROIC also solves for the gas temperature by applying the condition of radiative equilibrium. We present benchmarks and tests of the Comptonization module in HEROIC with simple 1D and 3D scattering problems. We also test the ability of the code to handle various relativistic effects using model atmospheres and accretion flows in a black hole space-time. We present two applications of HEROIC to general relativistic magnetohydrodynamics simulations of accretion discs. One application is to a thin accretion disc around a black hole. We find that the gas below the photosphere in the multidimensional HEROIC solution is nearly isothermal, quite different from previous solutions based on 1D plane parallel atmospheres. The second application is to a geometrically thick radiation-dominated accretion disc accreting at 11 times the Eddington rate. Here, the multidimensional HEROIC solution shows that, for observers who are on axis and look down the polar funnel, the isotropic equivalent luminosity could be more than 10 times the Eddington limit, even though the spectrum might still look thermal and show no signs of relativistic beaming.

  8. Investigating post-impact climate scenarios for early Mars with a 3D GCM

    NASA Astrophysics Data System (ADS)

    Steakley, K.; Murphy, J. R.; Kahre, M. A.; Haberle, R. M.

    2016-12-01

    The nature of the early martian climate has been long debated within the Mars community, with observations of valley networks implying a late Noachian/early Hesperian climate with extended periods of above-freezing temperatures and possibly recurring precipitation (Fassett & Head 2008, Icarus 195, 61; Hynek et al., 2010, JGR Planets, 115, E09008), while climate models produce cold and icy versions of early Mars (Forget et al., 2013, Icarus 21, 81). Volcanism and impacts have been proposed as mechanisms to introduce greenhouse gases and energy that might produce global warm and wet conditions or cause local melting in an otherwise cold and icy environment. Segura et al. (2008, JGR Planets 113, E11007) find using a 1-D atmospheric model that significant rainfall and periods of above-freezing temperatures lasting months to years can follow impacts from objects between 30 and 100 km in diameter. We use the NASA ARC Mars Global Climate Model (GCM) to expand on this work and investigate the possibility of globally increasing surface temperatures and inducing rainfall following large impacts, now considering the global effects of dynamics, topography, etc. The kinetic energy from a large impact can raise surface and atmospheric temperatures as hot rock vaporized or melted on impact is transported globally (Segura et al., 2008, JGR Planets 113, E11007). Water vapor is also injected into the atmosphere both from the impactor itself and from subsurface ice that is vaporized and excavated during crater formation (Segura et al., 2008, JGR Planets 113, E11007). Simple scaling relations are used to predict the quantities of water and energy deposited into the atmosphere following impacts from objects 30 to 100 km in size that are 12.5% water by volume and traveling at 8 km/s on impact. We present preliminary 3D GCM results of the effects of these post-impact conditions on early Mars climate scenarios.

  9. 3D MR ventricle segmentation in pre-term infants with post-hemorrhagic ventricle dilation

    NASA Astrophysics Data System (ADS)

    Qiu, Wu; Yuan, Jing; Kishimoto, Jessica; Chen, Yimin; de Ribaupierre, Sandrine; Chiu, Bernard; Fenster, Aaron

    2015-03-01

    Intraventricular hemorrhage (IVH) or bleed within the brain is a common condition among pre-term infants that occurs in very low birth weight preterm neonates. The prognosis is further worsened by the development of progressive ventricular dilatation, i.e., post-hemorrhagic ventricle dilation (PHVD), which occurs in 10-30% of IVH patients. In practice, predicting PHVD accurately and determining if that specific patient with ventricular dilatation requires the ability to measure accurately ventricular volume. While monitoring of PHVD in infants is typically done by repeated US and not MRI, once the patient has been treated, the follow-up over the lifetime of the patient is done by MRI. While manual segmentation is still seen as a gold standard, it is extremely time consuming, and therefore not feasible in a clinical context, and it also has a large inter- and intra-observer variability. This paper proposes a segmentation algorithm to extract the cerebral ventricles from 3D T1- weighted MR images of pre-term infants with PHVD. The proposed segmentation algorithm makes use of the convex optimization technique combined with the learned priors of image intensities and label probabilistic map, which is built from a multi-atlas registration scheme. The leave-one-out cross validation using 7 PHVD patient T1 weighted MR images showed that the proposed method yielded a mean DSC of 89.7% +/- 4.2%, a MAD of 2.6 +/- 1.1 mm, a MAXD of 17.8 +/- 6.2 mm, and a VD of 11.6% +/- 5.9%, suggesting a good agreement with manual segmentations.

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

    PubMed

    Yoshida, Hiroyuki; Wu, Yin; Cai, Wenli

    2014-03-19

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

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

    PubMed Central

    Yoshida, Hiroyuki; Wu, Yin; Cai, Wenli

    2014-01-01

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

  12. 3D Machine Vision and Additive Manufacturing: Concurrent Product and Process Development

    NASA Astrophysics Data System (ADS)

    Ilyas, Ismet P.

    2013-06-01

    The manufacturing environment rapidly changes in turbulence fashion. Digital manufacturing (DM) plays a significant role and one of the key strategies in setting up vision and strategic planning toward the knowledge based manufacturing. An approach of combining 3D machine vision (3D-MV) and an Additive Manufacturing (AM) may finally be finding its niche in manufacturing. This paper briefly overviews the integration of the 3D machine vision and AM in concurrent product and process development, the challenges and opportunities, the implementation of the 3D-MV and AM at POLMAN Bandung in accelerating product design and process development, and discusses a direct deployment of this approach on a real case from our industrial partners that have placed this as one of the very important and strategic approach in research as well as product/prototype development. The strategic aspects and needs of this combination approach in research, design and development are main concerns of the presentation.

  13. The role of extra-foveal processing in 3D imaging

    NASA Astrophysics Data System (ADS)

    Eckstein, Miguel P.; Lago, Miguel A.; Abbey, Craig K.

    2017-03-01

    The field of medical image quality has relied on the assumption that metrics of image quality for simple visual detection tasks are a reliable proxy for the more clinically realistic visual search tasks. Rank order of signal detectability across conditions often generalizes from detection to search tasks. Here, we argue that search in 3D images represents a paradigm shift in medical imaging: radiologists typically cannot exhaustively scrutinize all regions of interest with the high acuity fovea requiring detection of signals with extra-foveal areas (visual periphery) of the human retina. We hypothesize that extra-foveal processing can alter the detectability of certain types of signals in medical images with important implications for search in 3D medical images. We compare visual search of two different types of signals in 2D vs. 3D images. We show that a small microcalcification-like signal is more highly detectable than a larger mass-like signal in 2D search, but its detectability largely decreases (relative to the larger signal) in the 3D search task. Utilizing measurements of observer detectability as a function retinal eccentricity and observer eye fixations we can predict the pattern of results in the 2D and 3D search studies. Our findings: 1) suggest that observer performance findings with 2D search might not always generalize to 3D search; 2) motivate the development of a new family of model observers that take into account the inhomogeneous visual processing across the retina (foveated model observers).

  14. Clinical application of 3D-printed-step-bolus in post-total-mastectomy electron conformal therapy

    PubMed Central

    Park, Kwangwoo; Park, Sungjin; Jeon, Mi-Jin; Choi, Jinhyun; Kim, Jun Won; Cho, Yoon Jin; Jang, Won-Seok; Keum, Yo Sup; Lee, Ik Jae

    2017-01-01

    The 3D-printed boluses were used during the radiation therapy of the chest wall in six patients with breast cancer after modified radical mastectomy (MRM). We measured the in-vivo skin doses while both conventional and 3D-printed boluses were placed on the chest wall and compared the mean doses delivered to the ipsilateral lung and the heart. The homogeneity and conformity of the dose distribution in the chest wall for both types of boluses were also evaluated. The uniformity index on the chest skin was improved when the 3D-printed boluses were used, with the overall average skin dose being closer to the prescribed one in the former case (-0.47% versus -4.43%). On comparing the dose-volume histogram (DVH), it was found that the 3D-printed boluses resulted in a reduction in the mean dose to the ipsilateral lung by up to 20%. The precision of dose delivery was improved by 3% with the 3D-printed boluses; in contrast, the conventional step bolus resulted in a precision level of 5%. In conclusion, the use of the 3D-printed boluses resulted in better dose homogeneity and conformity to the chest wall as well as the sparing of the normal organs, especially the lung. This suggested that their routine use on the chest wall as a therapeutic approach during post-mastectomy radiation therapy offers numerous advantages over conventional step boluses. PMID:27784001

  15. Clinical application of 3D-printed-step-bolus in post-total-mastectomy electron conformal therapy.

    PubMed

    Park, Kwangwoo; Park, Sungjin; Jeon, Mi-Jin; Choi, Jinhyun; Kim, Jun Won; Cho, Yoon Jin; Jang, Won-Seok; Keum, Yo Sup; Lee, Ik Jae

    2017-04-11

    The 3D-printed boluses were used during the radiation therapy of the chest wall in six patients with breast cancer after modified radical mastectomy (MRM). We measured the in-vivo skin doses while both conventional and 3D-printed boluses were placed on the chest wall and compared the mean doses delivered to the ipsilateral lung and the heart. The homogeneity and conformity of the dose distribution in the chest wall for both types of boluses were also evaluated. The uniformity index on the chest skin was improved when the 3D-printed boluses were used, with the overall average skin dose being closer to the prescribed one in the former case (-0.47% versus -4.43%). On comparing the dose-volume histogram (DVH), it was found that the 3D-printed boluses resulted in a reduction in the mean dose to the ipsilateral lung by up to 20%. The precision of dose delivery was improved by 3% with the 3D-printed boluses; in contrast, the conventional step bolus resulted in a precision level of 5%. In conclusion, the use of the 3D-printed boluses resulted in better dose homogeneity and conformity to the chest wall as well as the sparing of the normal organs, especially the lung. This suggested that their routine use on the chest wall as a therapeutic approach during post-mastectomy radiation therapy offers numerous advantages over conventional step boluses.

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

    NASA Astrophysics Data System (ADS)

    Yoshida, Hiroyuki; Wu, Yin; Cai, Wenli

    2014-03-01

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

  17. The relationship between post-traumatic ossicular injuries and conductive hearing loss: A 3D-CT study.

    PubMed

    Maillot, Olivier; Attyé, Arnaud; Boutet, Claire; Boubagra, Kamel; Perolat, Romain; Zanolla, Marion; Grand, Sylvie; Schmerber, Sébastien; Krainik, Alexandre

    2017-09-01

    After a trauma, the conductive ossicular chain may be disrupted by ossicular luxation or fracture. Recent developments in 3D-CT allow a better understanding of ossicular injuries. In this retrospective study, we compared patients with post-traumatic conductive hearing loss (CHL) with those referred without CHL to evaluate the relationship between ossicular injuries and CHL. We also assessed the added value of 3D reconstructions on 2D-CT scan to detect ossicular lesions in patients surgically managed. The CT scans were performed using a 40-section spiral CT scanner in 49 patients with post-traumatic CHL (n=29) and without CHL (n=20). Three radiologists performed independent blind evaluations of 2D-CT and 3D reconstructions to detect ossicular chain injury. We used the t-test to explore differences regarding the number of subjects with ossicular injury in the two groups. We also estimated the diagnostic accuracy and the inter-rater agreement of the 3D-CT reconstructions associated to 2D-CT scan. We identified ossicular abnormality in 14 patients out of 29 and in one patient out of 20 in the CHL and non-CHL groups respectively. There was a significant difference regarding the number of subjects with ossicular lesions between the two groups (P≤0.01). The diagnostic sensitivity of 3D-CT reconstructions associated with 2D-CT ranged from 66% to 100% and the inter-reader agreement ranged from 0.85 to 1, depending of the type of lesion. The relationship between ossicular lesion and the presence of CHL tightly correlated. 3D-CT reconstructions of the temporal bone are useful to assess patients in a post-traumatic context. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  18. Effect of 3-D viscoelastic structure on post-seismic relaxation from the 2004 M = 9.2 Sumatra earthquake

    USGS Publications Warehouse

    Pollitz, F.; Banerjee, P.; Grijalva, K.; Nagarajan, B.; Burgmann, R.

    2008-01-01

    The 2004 M=9.2 Sumatra-Andaman earthquake profoundly altered the state of stress in a large volume surrounding the ???1400 km long rupture. Induced mantle flow fields and coupled surface deformation are sensitive to the 3-D rheology structure. To predict the post-seismic motions from this earthquake, relaxation of a 3-D spherical viscoelastic earth model is simulated using the theory of coupled normal modes. The quasi-static deformation basis set and solution on the 3-D model is constructed using: a spherically stratified viscoelastic earth model with a linear stress-strain relation; an aspherical perturbation in viscoelastic structure; a 'static'mode basis set consisting of Earth's spheroidal and toroidal free oscillations; a "viscoelastic" mode basis set; and interaction kernels that describe the coupling among viscoelastic and static modes. Application to the 2004 Sumatra-Andaman earthquake illustrates the profound modification of the post-seismic flow field at depth by a slab structure and similarly large effects on the near-field post-seismic deformation field at Earth's surface. Comparison with post-seismic GPS observations illustrates the extent to which viscoelastic relaxation contributes to the regional post-seismic deformation. ?? Journal compilation ?? 2008 RAS.

  19. Image processing and 3D visualization in the interpretation of patterned injury of the skin

    NASA Astrophysics Data System (ADS)

    Oliver, William R.; Altschuler, Bruce R.

    1995-09-01

    The use of image processing is becoming increasingly important in the evaluation of violent crime. While much work has been done in the use of these techniques for forensic purposes outside of forensic pathology, its use in the pathologic examination of wounding has been limited. We are investigating the use of image processing in the analysis of patterned injuries and tissue damage. Our interests are currently concentrated on 1) the use of image processing techniques to aid the investigator in observing and evaluating patterned injuries in photographs, 2) measurement of the 3D shape characteristics of surface lesions, and 3) correlation of patterned injuries with deep tissue injury as a problem in 3D visualization. We are beginning investigations in data-acquisition problems for performing 3D scene reconstructions from the pathology perspective of correlating tissue injury to scene features and trace evidence localization. Our primary tool for correlation of surface injuries with deep tissue injuries has been the comparison of processed surface injury photographs with 3D reconstructions from antemortem CT and MRI data. We have developed a prototype robot for the acquisition of 3D wound and scene data.

  20. Pre-Peak and Post-Peak Rock Strain Characteristics During Uniaxial Compression by 3D Digital Image Correlation

    NASA Astrophysics Data System (ADS)

    Munoz, H.; Taheri, A.; Chanda, E. K.

    2016-07-01

    A non-contact optical method for strain measurement applying three-dimensional digital image correlation (3D DIC) in uniaxial compression is presented. A series of monotonic uniaxial compression tests under quasi-static loading conditions on Hawkesbury sandstone specimens were conducted. A prescribed constant lateral-strain rate to control the applied axial load in a closed-loop system allowed capturing the complete stress-strain behaviour of the rock, i.e. the pre-peak and post-peak stress-strain regimes. 3D DIC uses two digital cameras to acquire images of the undeformed and deformed shape of an object to perform image analysis and provides deformation and motion measurements. Observations showed that 3D DIC provides strains free from bedding error in contrast to strains from LVDT. Erroneous measurements due to the compliance of the compressive machine are also eliminated. Furthermore, by 3D DIC technique relatively large strains developed in the post-peak regime, in particular within localised zones, difficult to capture by bonded strain gauges, can be measured in a straight forward manner. Field of strains and eventual strain localisation in the rock surface were analysed by 3D DIC method, coupled with the respective stress levels in the rock. Field strain development in the rock samples, both in axial and shear strain domains suggested that strain localisation takes place progressively and develops at a lower rate in pre-peak regime. It is accelerated, otherwise, in post-peak regime associated with the increasing rate of strength degradation. The results show that a major failure plane, due to strain localisation, becomes noticeable only long after the peak stress took place. In addition, post-peak stress-strain behaviour was observed to be either in a form of localised strain in a shearing zone or inelastic unloading outside of the shearing zone.

  1. Semi-implicit finite volume scheme for image processing in 3D cylindrical geometry

    NASA Astrophysics Data System (ADS)

    Mikula, Karol; Sgallari, Fiorella

    2003-12-01

    Nowadays, 3D echocardiography is a well-known technique in medical diagnosis. Inexpensive echocardiographic acquisition devices are applied to scan 2D slices rotated along a prescribed direction. Then the discrete 3D image information is given on a cylindrical grid. Usually, this original discrete image intensity function is interpolated to a uniform rectangular grid and then numerical schemes for 3D image processing operations (e.g. nonlinear smoothing) in the uniform rectangular geometry are used. However, due to the generally large amount of noise present in echocardiographic images, the interpolation step can yield undesirable results. In this paper, we avoid this step and suggest a 3D finite volume method for image selective smoothing directly in the cylindrical image geometry. Specifically, we study a semi-implicit 3D cylindrical finite volume scheme for solving a Perona-Malik-type nonlinear diffusion equation and apply the scheme to 3D cylindrical echocardiographic images. The L∞-stability and convergence of the scheme to the weak solution of the regularized Perona-Malik equation is proved.

  2. Possible use of a 3-D clinostat to analyze plant growth processes under microgravity conditions.

    PubMed

    Hoson, T; Kamisaka, S; Buchen, B; Sievers, A; Yamashita, M; Masuda, Y

    1996-01-01

    A three-dimensional (3-D) clinostat equipped with two rotation axes placed at right angles was constructed, and various growth processes of higher plants grown on this clinostat were compared with ground controls, with plants grown on the conventional horizontal clinostat, and with those under real microgravity in space. On the 3-D clinostat, cress roots developed a normal root cap and the statocytes showed the typical polar organization except a random distribution of statoliths. The structural features of clinostatted statocytes were fundamentally similar to those observed under real microgravity. The graviresponse of cress roots grown on the 3-D clinostat was the same as the control roots. On the 3-D clinostat, shoots and roots exhibited a spontaneous curvature as well as an altered growth direction. Such an automorphogenesis was sometimes exaggerated when plants were subjected to the horizontal rotation, whereas the curvature was suppressed on the vertical rotation. These discrepancies in curvature between the 3-D clinostat and the conventional ones appear to be brought about by the centrifugal force produced. Thus, the 3-D clinostat was proven as a useful device to simulate microgravity.

  3. Clinical application of modern imaging technology: 3D information acquiring and image processing

    NASA Astrophysics Data System (ADS)

    Wang, Dezong

    1994-05-01

    In current clinic, pictures of B-supersonic, X-ray, X-CT and MRI are applicated widely. All of these are 2D pictures. The 3D information is blended. The blended information always leads doctors astray. If images are processed, mistakes will be reduced. In this paper the processing methods of 2D images are described. Examples of clinical applications are given. The acquiring methods of 3D information from 2D images are explained. The stereo image of liver and cancer is shown. The calculating ways of areas and volumes of liver and cancer are provided.

  4. Geospatial Data Processing for 3d City Model Generation, Management and Visualization

    NASA Astrophysics Data System (ADS)

    Toschi, I.; Nocerino, E.; Remondino, F.; Revolti, A.; Soria, G.; Piffer, S.

    2017-05-01

    Recent developments of 3D technologies and tools have increased availability and relevance of 3D data (from 3D points to complete city models) in the geospatial and geo-information domains. Nevertheless, the potential of 3D data is still underexploited and mainly confined to visualization purposes. Therefore, the major challenge today is to create automatic procedures that make best use of available technologies and data for the benefits and needs of public administrations (PA) and national mapping agencies (NMA) involved in "smart city" applications. The paper aims to demonstrate a step forward in this process by presenting the results of the SENECA project (Smart and SustaiNablE City from Above - http://seneca.fbk.eu). State-of-the-art processing solutions are investigated in order to (i) efficiently exploit the photogrammetric workflow (aerial triangulation and dense image matching), (ii) derive topologically and geometrically accurate 3D geo-objects (i.e. building models) at various levels of detail and (iii) link geometries with non-spatial information within a 3D geo-database management system accessible via web-based client. The developed methodology is tested on two case studies, i.e. the cities of Trento (Italy) and Graz (Austria). Both spatial (i.e. nadir and oblique imagery) and non-spatial (i.e. cadastral information and building energy consumptions) data are collected and used as input for the project workflow, starting from 3D geometry capture and modelling in urban scenarios to geometry enrichment and management within a dedicated webGIS platform.

  5. Status of on-focal-plane signal processing utilizing 3D silicon technology

    NASA Astrophysics Data System (ADS)

    Carson, John C.

    1994-03-01

    3D silicon technology has been under development since 1980, primarily aimed at on-focal- plane signal processing to solve a variety of military sensor systems problems. The thrust has been to bring more and more parallel analog and digital processing into the closest possible proximity to the detector array. At this time on-focal-plane functionality includes preamplification, spatial and temporal matched filtering, nonuniformity correction, neural networks, analog-digital conversion, digital logic, and digital memory. Historically, a custom- built specialty technology constrained by cost in its applicability, 3D silicon has undergone a dual-use conversion to include high-volume, low-cost commercial computer electronics. 3D silicon is on the way to becoming the lowest-cost-per-gate technology available and, because of this, sensor system design and performance will be revolutionized.

  6. A measurement method for micro 3D shape based on grids-processing and stereovision technology

    NASA Astrophysics Data System (ADS)

    Li, Chuanwei; Liu, Zhanwei; Xie, Huimin

    2013-04-01

    An integrated measurement method for micro 3D surface shape by a combination of stereovision technology in a scanning electron microscope (SEM) and grids-processing methodology is proposed. The principle of the proposed method is introduced in detail. By capturing two images of the tested specimen with grids on the surface at different tilt angles in an SEM, the 3D surface shape of the specimen can be obtained. Numerical simulation is applied to analyze the feasibility of the proposed method. A validation experiment is performed here. The surface shape of the metal-wire/polymer-membrane structures with thermal deformation is reconstructed. By processing the surface grids of the specimen, the out-of-plane displacement field of the specimen surface is also obtained. Compared with the measurement results obtained by a 3D digital microscope, the experimental error of the proposed method is discussed

  7. Virtual 3D tumor marking-exact intraoperative coordinate mapping improve post-operative radiotherapy

    PubMed Central

    2011-01-01

    The quality of the interdisciplinary interface in oncological treatment between surgery, pathology and radiotherapy is mainly dependent on reliable anatomical three-dimensional (3D) allocation of specimen and their context sensitive interpretation which defines further treatment protocols. Computer-assisted preoperative planning (CAPP) allows for outlining macroscopical tumor size and margins. A new technique facilitates the 3D virtual marking and mapping of frozen sections and resection margins or important surgical intraoperative information. These data could be stored in DICOM format (Digital Imaging and Communication in Medicine) in terms of augmented reality and transferred to communicate patient's specific tumor information (invasion to vessels and nerves, non-resectable tumor) to oncologists, radiotherapists and pathologists. PMID:22087558

  8. Constraining 3D Process Sedimentological Models to Geophysical Data Using Image Quilting

    NASA Astrophysics Data System (ADS)

    Tahmasebi, P.; Da Pra, A.; Pontiggia, M.; Caers, J.

    2014-12-01

    3D process geological models, whether for carbonate or sedimentological systems, have been proposed for modeling realistic subsurface heterogeneity. The problem with such forward process models is that they are not constrained to any subsurface data whether to wells or geophysical surveys. We propose a new method for realistic geological modeling of complex heterogeneity by hybridizing 3D process modeling of geological deposition with conditioning by means of a novel multiple-point geostatistics (MPS) technique termed image quilting (IQ). Image quilting is a pattern-based techniques that stiches together patterns extracted from training images to generate stochastic realizations that look like the training image. In this paper, we illustrate how 3D process model realizations can be used as training images in image quilting. To constrain the realization to seismic data we first interpret each facies in the geophysical data. These interpretation, while overly smooth and not reflecting finer scale variation are used as auxiliary variables in the generation of the image quilting realizations. To condition to well data, we first perform a kriging of the well data to generate a kriging map and kriging variance. The kriging map is used as additional auxiliary variable while the kriging variance is used as a weight given to the kriging derived auxiliary variable. We present an application to a giant offshore reservoir. Starting from seismic advanced attribute analysis and sedimentological interpretation, we build the 3D sedimentological process based model and use it as non-stationary training image for conditional image quilting.

  9. A Critical Analysis of a Hand Orthosis Reverse Engineering and 3D Printing Process

    PubMed Central

    2016-01-01

    The possibility to realize highly customized orthoses is receiving boost thanks to the widespread diffusion of low-cost 3D printing technologies. However, rapid prototyping (RP) with 3D printers is only the final stage of patient personalized orthotics processes. A reverse engineering (RE) process is in fact essential before RP, to digitize the 3D anatomy of interest and to process the obtained surface with suitable modeling software, in order to produce the virtual solid model of the orthosis to be printed. In this paper, we focus on the specific and demanding case of the customized production of hand orthosis. We design and test the essential steps of the entire production process with particular emphasis on the accurate acquisition of the forearm geometry and on the subsequent production of a printable model of the orthosis. The choice of the various hardware and software tools (3D scanner, modeling software, and FDM printer) is aimed at the mitigation of the design and production costs while guaranteeing suitable levels of data accuracy, process efficiency, and design versatility. Eventually, the proposed method is critically analyzed so that the residual issues and critical aspects are highlighted in order to discuss possible alternative approaches and to derive insightful observations that could guide future research activities. PMID:27594781

  10. A Critical Analysis of a Hand Orthosis Reverse Engineering and 3D Printing Process.

    PubMed

    Baronio, Gabriele; Harran, Sami; Signoroni, Alberto

    2016-01-01

    The possibility to realize highly customized orthoses is receiving boost thanks to the widespread diffusion of low-cost 3D printing technologies. However, rapid prototyping (RP) with 3D printers is only the final stage of patient personalized orthotics processes. A reverse engineering (RE) process is in fact essential before RP, to digitize the 3D anatomy of interest and to process the obtained surface with suitable modeling software, in order to produce the virtual solid model of the orthosis to be printed. In this paper, we focus on the specific and demanding case of the customized production of hand orthosis. We design and test the essential steps of the entire production process with particular emphasis on the accurate acquisition of the forearm geometry and on the subsequent production of a printable model of the orthosis. The choice of the various hardware and software tools (3D scanner, modeling software, and FDM printer) is aimed at the mitigation of the design and production costs while guaranteeing suitable levels of data accuracy, process efficiency, and design versatility. Eventually, the proposed method is critically analyzed so that the residual issues and critical aspects are highlighted in order to discuss possible alternative approaches and to derive insightful observations that could guide future research activities.

  11. F3D Image Processing and Analysis for Many - and Multi-core Platforms

    SciTech Connect

    2014-10-01

    F3D is written in OpenCL, so it achieve[sic] platform-portable parallelism on modern mutli-core CPUs and many-core GPUs. The interface and mechanims to access F3D core are written in Java as a plugin for Fiji/ImageJ to deliver several key image-processing algorithms necessary to remove artifacts from micro-tomography data. The algorithms consist of data parallel aware filters that can efficiently utilizes[sic] resources and can work on out of core datasets and scale efficiently across multiple accelerators. Optimizing for data parallel filters, streaming out of core datasets, and efficient resource and memory and data managements over complex execution sequence of filters greatly expedites any scientific workflow with image processing requirements. F3D performs several different types of 3D image processing operations, such as non-linear filtering using bilateral filtering and/or median filtering and/or morphological operators (MM). F3D gray-level MM operators are one-pass constant time methods that can perform morphological transformations with a line-structuring element oriented in discrete directions. Additionally, MM operators can be applied to gray-scale images, and consist of two parts: (a) a reference shape or structuring element, which is translated over the image, and (b) a mechanism, or operation, that defines the comparisons to be performed between the image and the structuring element. This tool provides a critical component within many complex pipelines such as those for performing automated segmentation of image stacks. F3D is also called a "descendent" of Quant-CT, another software we developed in the past. These two modules are to be integrated in a next version. Further details were reported in: D.M. Ushizima, T. Perciano, H. Krishnan, B. Loring, H. Bale, D. Parkinson, and J. Sethian. Structure recognition from high-resolution images of ceramic composites. IEEE International Conference on Big Data, October 2014.

  12. F3D Image Processing and Analysis for Many - and Multi-core Platforms

    SciTech Connect

    2014-10-01

    F3D is written in OpenCL, so it achieve[sic] platform-portable parallelism on modern mutli-core CPUs and many-core GPUs. The interface and mechanims to access F3D core are written in Java as a plugin for Fiji/ImageJ to deliver several key image-processing algorithms necessary to remove artifacts from micro-tomography data. The algorithms consist of data parallel aware filters that can efficiently utilizes[sic] resources and can work on out of core datasets and scale efficiently across multiple accelerators. Optimizing for data parallel filters, streaming out of core datasets, and efficient resource and memory and data managements over complex execution sequence of filters greatly expedites any scientific workflow with image processing requirements. F3D performs several different types of 3D image processing operations, such as non-linear filtering using bilateral filtering and/or median filtering and/or morphological operators (MM). F3D gray-level MM operators are one-pass constant time methods that can perform morphological transformations with a line-structuring element oriented in discrete directions. Additionally, MM operators can be applied to gray-scale images, and consist of two parts: (a) a reference shape or structuring element, which is translated over the image, and (b) a mechanism, or operation, that defines the comparisons to be performed between the image and the structuring element. This tool provides a critical component within many complex pipelines such as those for performing automated segmentation of image stacks. F3D is also called a "descendent" of Quant-CT, another software we developed in the past. These two modules are to be integrated in a next version. Further details were reported in: D.M. Ushizima, T. Perciano, H. Krishnan, B. Loring, H. Bale, D. Parkinson, and J. Sethian. Structure recognition from high-resolution images of ceramic composites. IEEE International Conference on Big Data, October 2014.

  13. Spatiotemporal Evolution of the Wound Repairing Process in a 3D Human Dermis Equivalent.

    PubMed

    Lombardi, Bernadette; Casale, Costantino; Imparato, Giorgia; Urciuolo, Francesco; Netti, Paolo Antonio

    2017-07-01

    Several skin equivalent models have been developed to investigate in vitro the re-epithelialization process occurring during wound healing. Although these models recapitulate closure dynamics of epithelial cells, they fail to capture how a wounded connective tissue rebuilds its 3D architecture until the evolution in a scar. Here, the in vitro tissue repair dynamics of a connective tissue is replicated by using a 3D human dermis equivalent (3D-HDE) model composed of fibroblasts embedded in their own extracellular matrix (ECM). After inducing a physical damage, 3D-HDE undergoes a series of cellular and extracellular events quite similar to those occurring in the native dermis. In particular, fibroblasts differentiation toward myofibroblasts phenotype and neosynthesis of hyaluronic acid, fibronectin, and collagen during the repair process are assessed. Moreover, tissue reorganization after physical damage is investigated by measuring the diameter of bundles and the orientation of fibers of the newly formed ECM network. Finally, the ultimate formation of a scar-like tissue as physiological consequence of the repair and closure process is demonstrated. Taking together, the results highlight that the presence of cell-assembled and responsive stromal components enables quantitative and qualitative in vitro evaluation of the processes involved in scarring during wound healing. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. 3D multi-layered fibrous cellulose structure using an electrohydrodynamic process for tissue engineering.

    PubMed

    Kim, Minseong; Kim, GeunHyung

    2015-11-01

    Micro/nanofibrous structures have been applied widely in various tissue-engineering applications because the topological structures are similar to the extracellular matrix (ECM), which encourages a high degree of cell adhesion and growth. However, it has been difficult to produce a three-dimensional (3D) fibrous structure using controllable macro-pores. Recently, cellulose has been considered a high-potential natural-origin biomaterial, but its use in 3D biomedical structures has been limited due to its narrow processing window. Here, we suggest a new 3D cellulose scaffold consisting of multi-layered struts made of submicron-sized entangled fibers that were fabricated using an electrohydrodynamic direct jet (EHDJ) process that is spin-printing. By optimizing processing conditions (electric field strength, cellulose feeding rate, and distance between nozzle and target), we can achieve a multi-layered cellulose structure consisting of the cylindrically entangled cellulose fibers. To compare the properties of the fabricated 3D cellulose structure, we used a PCL fibrous scaffold, which has a similar fibrous morphology and pore geometry, as a control. The physical and in vitro biocompatibilities of both fibrous scaffolds were assessed using human dermal fibroblasts, and the cellulose structure showed higher cell adhesion and metabolic activities compared with the control. These results suggest the EHDJ process to be an effective fabricating tool for tissue engineering and the cellulose scaffold has high potential as a tissue regenerative material.

  15. 3D computed tomography of an unusual triple ended xiphoid process.

    PubMed

    Mosca, Heather; Dross, Peter

    2012-03-01

    The sternum is the site of frequent variations and anomalies. Knowledge of the plain film and CT appearance of these variations and anomalies is useful in differentiating from pathologic conditions and in surgical planning. We present a rare case of an unusual triple ended xiphoid process with its plain film and 3D CT volume rendered reconstructed imaging.

  16. Development of a 3-D Measuring System for Upper Limb Movements Using Image Processing

    NASA Astrophysics Data System (ADS)

    Ogata, Kohichi; Toume, Tadashi; Nakanishi, Ryoji

    This paper describes a 3-D motion capture system for the quantitative evaluation of a finger-nose test using image processing. In the field of clinical medicine, qualitative and quantitative evaluation of voluntary movements is necessary for correct diagnosis of disorders. For this purpose, we have developed a 3-D measuring system with a multi-camera system. The configuration of the system is described and examples of movement data are shown for normal subjects and patients. In the finger-nose test at a fast trial speed, a discriminant analysis using Maharanobis generalized distances shows a discriminant rate of 93% between normal subjects and spinocerebellar degeneration(SCD) patients.

  17. Taking advantage of selective change driven processing for 3D scanning.

    PubMed

    Vegara, Francisco; Zuccarello, Pedro; Boluda, Jose A; Pardo, Fernando

    2013-09-27

    This article deals with the application of the principles of SCD (Selective Change Driven) vision to 3D laser scanning. Two experimental sets have been implemented: one with a classical CMOS (Complementary Metal-Oxide Semiconductor) sensor, and the other one with a recently developed CMOS SCD sensor for comparative purposes, both using the technique known as Active Triangulation. An SCD sensor only delivers the pixels that have changed most, ordered by the magnitude of their change since their last readout. The 3D scanning method is based on the systematic search through the entire image to detect pixels that exceed a certain threshold, showing the SCD approach to be ideal for this application. Several experiments for both capturing strategies have been performed to try to find the limitations in high speed acquisition/processing. The classical approach is limited by the sequential array acquisition, as predicted by the Nyquist-Shannon sampling theorem, and this has been experimentally demonstrated in the case of a rotating helix. These limitations are overcome by the SCD 3D scanning prototype achieving a significantly higher performance. The aim of this article is to compare both capturing strategies in terms of performance in the time and frequency domains, so they share all the static characteristics including resolution, 3D scanning method, etc., thus yielding the same 3D reconstruction in static scenes.

  18. Taking Advantage of Selective Change Driven Processing for 3D Scanning

    PubMed Central

    Vegara, Francisco; Zuccarello, Pedro; Boluda, Jose A.; Pardo, Fernando

    2013-01-01

    This article deals with the application of the principles of SCD (Selective Change Driven) vision to 3D laser scanning. Two experimental sets have been implemented: one with a classical CMOS (Complementary Metal-Oxide Semiconductor) sensor, and the other one with a recently developed CMOS SCD sensor for comparative purposes, both using the technique known as Active Triangulation. An SCD sensor only delivers the pixels that have changed most, ordered by the magnitude of their change since their last readout. The 3D scanning method is based on the systematic search through the entire image to detect pixels that exceed a certain threshold, showing the SCD approach to be ideal for this application. Several experiments for both capturing strategies have been performed to try to find the limitations in high speed acquisition/processing. The classical approach is limited by the sequential array acquisition, as predicted by the Nyquist–Shannon sampling theorem, and this has been experimentally demonstrated in the case of a rotating helix. These limitations are overcome by the SCD 3D scanning prototype achieving a significantly higher performance. The aim of this article is to compare both capturing strategies in terms of performance in the time and frequency domains, so they share all the static characteristics including resolution, 3D scanning method, etc., thus yielding the same 3D reconstruction in static scenes. PMID:24084110

  19. Sensitivity Analysis and Optimization Algorithms for 3D Forging Process Design

    NASA Astrophysics Data System (ADS)

    Do, T. T.; Fourment, L.; Laroussi, M.

    2004-06-01

    This paper presents several approaches for preform shape optimization in 3D forging. The process simulation is carried out using the FORGE3® finite element software, and the optimization problem regards the shape of initial axisymmetrical preforms. Several objective functions are considered, like the forging energy, the forging force or a surface defect criterion. Both deterministic and stochastic optimization algorithms are tested for 3D applications. The deterministic approach uses the sensitivity analysis that provides the gradient of the objective function. It is obtained by the adjoint-state method and semi-analytical differentiation. The study of stochastic approaches aims at comparing genetic algorithms and evolution strategies. Numerical results show the feasibility of such approaches, i.e. the achieving of satisfactory solutions within a limited number of 3D simulations, less than fifty. For a more industrial problem, the forging of a gear, encouraging optimization results are obtained.

  20. Device considerations and characterizations of pre and post fabricated GaAs based pHEMTs using multilayer 3D MMIC technology

    NASA Astrophysics Data System (ADS)

    Alim, Mohammad A.; Ali, Mayahsa M.; Haris, Norshakila; Kyabaggu, Peter B. K.; Rezazadeh, Ali A.

    2017-05-01

    This study focuses on the characterization of two 0.5 μm gate-length double heterojunction AlGaAs/InGaAs/GaAs pHEMTs using pre and post fabricated vertical oriented multilayer 3D monolithic microwave integrated (MMIC) circuit technology. The effects of the presence of 3D components above the active layer were accomplished by means of capacitance-voltage measurement, on-wafer DC and S-parameter measurements and two-tone intermodulation distortion measurement. The barrier height, donor concentration in the barrier layer, existing two-dimensional electron gas, output current, off and on state leakage, transconductance, cut-off frequency, small signal model parameters, gain, minimum noise figures and nonlinear distortion behavior reveals no significant performance degradation. Furthermore the fundamental device properties such as the depletion depth d, the sheet charge densities of the 2-DEG, n s, filed dependent mobility, μ, and the effective carrier velocity, v eff is not much affected due to multilayer processing. Less than 5% changes in magnitude of the device parameters are realized between the pre and post fabricated multilayer 3D MMIC technology. These effective comparisons of the both device are useful for future designs and optimizations of multilayer vertical stacked 3D MMICs.

  1. Experimental investigation of 3D scanheads for laser micro-processing

    NASA Astrophysics Data System (ADS)

    Penchev, Pavel; Dimov, Stefan; Bhaduri, Debajyoti

    2016-07-01

    The broader use of laser micro-processing technology increases the demand for executing complex machining and joining operations on free-from (3D) workpieces. To satisfy these growing requirements it is necessary to utilise 3D scanheads that integrate beam deflectors (X and Y optical axes) and Z modules with high dynamics. The research presented in this communication proposes an experimental technique to quantify the dynamic capabilities of Z modules, also called Dynamic Focusing Modules (DFM), of such 3D scanheads that are essential for efficient, accurate and repeatable laser micro-processing of free form surfaces. The proposed experimental technique is validated on state-of-art laser micro-machining platform and the results show that the DFM dynamic capabilities are substantially inferior than those of X and Y beam deflectors, in particular the maximum speed of the Z module is less than 10% of the maximum speeds achievable with X and Y optical axes of the scanhead. Thus, the DFM dynamics deficiencies can become a major obstacle for the broader use of high frequency laser sources that necessitate high dynamics 3D scanheads for executing cost effectively free-form surface processing operations.

  2. Novel processing of iron-manganese alloy-based biomaterials by inkjet 3-D printing.

    PubMed

    Chou, Da-Tren; Wells, Derrick; Hong, Daeho; Lee, Boeun; Kuhn, Howard; Kumta, Prashant N

    2013-11-01

    The present work provides an assessment of 3-D printed iron-manganese biodegradable scaffolds as a bone scaffold material. Iron-based alloys have been investigated due to their high strength and ability to slowly corrode. Current fabrications of Fe-based materials generate raw material which must be machined into their desired form. By using inkjet 3-D printing, a technique which generates complex, customizable parts from powders mechanically milled Fe-30Mn (wt.%) powder was directly processed into scaffolds. The 3-D printed parts maintained an open porosity of 36.3% and formed a mixed phase alloy of martensitic ε and austenitic γ phases. Electrochemical corrosion tests showed the 3-D printed Fe-Mn to desirably corrode significantly more rapidly than pure iron. The scaffolds exhibited similar tensile mechanical properties to natural bone, which may reduce the risk of stress shielding. Cell viability testing of MC3T3-E1 pre-osteoblast cells seeded directly onto the Fe-Mn scaffolds using the live/dead assay and with cells cultured in the presence of the scaffolds' degradation products demonstrated good in vitro cytocompatibility compared to tissue culture plastic. Cell infiltration into the open pores of the 3-D printed scaffolds was also observed. Based on this preliminary study, we believe that 3-D printed Fe-Mn alloy is a promising material for craniofacial biomaterial applications, and represents an opportunity for other biodegradable metals to be fabricated using this unique method. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  3. 3D Printing All-Aromatic Polyimides using Mask-Projection Stereolithography: Processing the Nonprocessable.

    PubMed

    Hegde, Maruti; Meenakshisundaram, Viswanath; Chartrain, Nicholas; Sekhar, Susheel; Tafti, Danesh; Williams, Christopher B; Long, Timothy E

    2017-08-01

    High-performance, all-aromatic, insoluble, engineering thermoplastic polyimides, such as pyromellitic dianhydride and 4,4'-oxydianiline (PMDA-ODA) (Kapton), exhibit exceptional thermal stability (up to ≈600 °C) and mechanical properties (Young's modulus exceeding 2 GPa). However, their thermal resistance, which is a consequence of the all-aromatic molecular structure, prohibits processing using conventional techniques. Previous reports describe an energy-intensive sintering technique as an alternative technique for processing polyimides with limited resolution and part fidelity. This study demonstrates the unprecedented 3D printing of PMDA-ODA using mask-projection stereolithography, and the preparation of high-resolution 3D structures without sacrificing bulk material properties. Synthesis of a soluble precursor polymer containing photo-crosslinkable acrylate groups enables light-induced, chemical crosslinking for spatial control in the gel state. Postprinting thermal treatment transforms the crosslinked precursor polymer to PMDA-ODA. The dimensional shrinkage is isotropic, and postprocessing preserves geometric integrity. Furthermore, large-area mask-projection scanning stereolithography demonstrates the scalability of 3D structures. These unique high-performance 3D structures offer potential in fields ranging from water filtration and gas separation to automotive and aerospace technologies. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

    PubMed Central

    Tetsworth, Kevin; Block, Steve; Glatt, Vaida

    2017-01-01

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

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

    PubMed

    Tetsworth, Kevin; Block, Steve; Glatt, Vaida

    2017-01-01

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

  6. WASS: an open-source stereo processing pipeline for sea waves 3D reconstruction

    NASA Astrophysics Data System (ADS)

    Bergamasco, Filippo; Benetazzo, Alvise; Torsello, Andrea; Barbariol, Francesco; Carniel, Sandro; Sclavo, Mauro

    2017-04-01

    Stereo 3D reconstruction of ocean waves is gaining more and more popularity in the oceanographic community. In fact, recent advances of both computer vision algorithms and CPU processing power can now allow the study of the spatio-temporal wave fields with unprecedented accuracy, especially at small scales. Even if simple in theory, multiple details are difficult to be mastered for a practitioner so that the implementation of a 3D reconstruction pipeline is in general considered a complex task. For instance, camera calibration, reliable stereo feature matching and mean sea-plane estimation are all factors for which a well designed implementation can make the difference to obtain valuable results. For this reason, we believe that the open availability of a well-tested software package that automates the steps from stereo images to a 3D point cloud would be a valuable addition for future researches in this area. We present WASS, a completely Open-Source stereo processing pipeline for sea waves 3D reconstruction, available at http://www.dais.unive.it/wass/. Our tool completely automates the recovery of dense point clouds from stereo images by providing three main functionalities. First, WASS can automatically recover the extrinsic parameters of the stereo rig (up to scale) so that no delicate calibration has to be performed on the field. Second, WASS implements a fast 3D dense stereo reconstruction procedure so that an accurate 3D point cloud can be computed from each stereo pair. We rely on the well-consolidated OpenCV library both for the image stereo rectification and disparity map recovery. Lastly, a set of 2D and 3D filtering techniques both on the disparity map and the produced point cloud are implemented to remove the vast majority of erroneous points that can naturally arise while analyzing the optically complex nature of the water surface (examples are sun-glares, large white-capped areas, fog and water areosol, etc). Developed to be as fast as possible, WASS

  7. 3D transient model to predict temperature and ablated areas during laser processing of metallic surfaces

    NASA Astrophysics Data System (ADS)

    Naghshine, Babak. B.; Kiani, Amirkianoosh

    2017-02-01

    Laser processing is one of the most popular small-scale patterning methods and has many applications in semiconductor device fabrication and biomedical engineering. Numerical modelling of this process can be used for better understanding of the process, optimization, and predicting the quality of the final product. An accurate 3D model is presented here for short laser pulses that can predict the ablation depth and temperature distribution on any section of the material in a minimal amount of time. In this transient model, variations of thermal properties, plasma shielding, and phase change are considered. Ablation depth was measured using a 3D optical profiler. Calculated depths are in good agreement with measured values on laser treated titanium surfaces. The proposed model can be applied to a wide range of materials and laser systems.

  8. 3D TEM reconstruction and segmentation process of laminar bio-nanocomposites

    SciTech Connect

    Iturrondobeitia, M. Okariz, A.; Fernandez-Martinez, R.; Jimbert, P.; Guraya, T.; Ibarretxe, J.

    2015-03-30

    The microstructure of laminar bio-nanocomposites (Poly (lactic acid)(PLA)/clay) depends on the amount of clay platelet opening after integration with the polymer matrix and determines the final properties of the material. Transmission electron microscopy (TEM) technique is the only one that can provide a direct observation of the layer dispersion and the degree of exfoliation. However, the orientation of the clay platelets, which affects the final properties, is practically immeasurable from a single 2D TEM image. This issue can be overcome using transmission electron tomography (ET), a technique that allows the complete 3D characterization of the structure, including the measurement of the orientation of clay platelets, their morphology and their 3D distribution. ET involves a 3D reconstruction of the study volume and a subsequent segmentation of the study object. Currently, accurate segmentation is performed manually, which is inefficient and tedious. The aim of this work is to propose an objective/automated segmentation methodology process of a 3D TEM tomography reconstruction. In this method the segmentation threshold is optimized by minimizing the variation of the dimensions of the segmented objects and matching the segmented V{sub clay} (%) and the actual one. The method is first validated using a fictitious set of objects, and then applied on a nanocomposite.

  9. Separate Perceptual and Neural Processing of Velocity- and Disparity-Based 3D Motion Signals.

    PubMed

    Joo, Sung Jun; Czuba, Thaddeus B; Cormack, Lawrence K; Huk, Alexander C

    2016-10-19

    Although the visual system uses both velocity- and disparity-based binocular information for computing 3D motion, it is unknown whether (and how) these two signals interact. We found that these two binocular signals are processed distinctly at the levels of both cortical activity in human MT and perception. In human MT, adaptation to both velocity-based and disparity-based 3D motions demonstrated direction-selective neuroimaging responses. However, when adaptation to one cue was probed using the other cue, there was no evidence of interaction between them (i.e., there was no "cross-cue" adaptation). Analogous psychophysical measurements yielded correspondingly weak cross-cue motion aftereffects (MAEs) in the face of very strong within-cue adaptation. In a direct test of perceptual independence, adapting to opposite 3D directions generated by different binocular cues resulted in simultaneous, superimposed, opposite-direction MAEs. These findings suggest that velocity- and disparity-based 3D motion signals may both flow through area MT but constitute distinct signals and pathways.

  10. Comparison Between Two Generic 3d Building Reconstruction Approaches - Point Cloud Based VS. Image Processing Based

    NASA Astrophysics Data System (ADS)

    Dahlke, D.; Linkiewicz, M.

    2016-06-01

    This paper compares two generic approaches for the reconstruction of buildings. Synthesized and real oblique and vertical aerial imagery is transformed on the one hand into a dense photogrammetric 3D point cloud and on the other hand into photogrammetric 2.5D surface models depicting a scene from different cardinal directions. One approach evaluates the 3D point cloud statistically in order to extract the hull of structures, while the other approach makes use of salient line segments in 2.5D surface models, so that the hull of 3D structures can be recovered. With orders of magnitudes more analyzed 3D points, the point cloud based approach is an order of magnitude more accurate for the synthetic dataset compared to the lower dimensioned, but therefor orders of magnitude faster, image processing based approach. For real world data the difference in accuracy between both approaches is not significant anymore. In both cases the reconstructed polyhedra supply information about their inherent semantic and can be used for subsequent and more differentiated semantic annotations through exploitation of texture information.

  11. Ship Maintenance Processes with Collaborative Product Lifecycle Management and 3D Terrestrial Laser Scanning Tools: Reducing Costs and Increasing Productivity

    DTIC Science & Technology

    2012-04-30

    approach that incorporates the 3D terrestrial laser scanning (3D TLS) and collaborative product lifecycle management (collab- PLM ) tool suite. Results...incorporated into final implementation of the 3D TLS and collab- PLM tools. 15. SUBJECT TERMS 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF...terrestrial laser scanning (3D TLS) and collaborative product lifecycle management (collab- PLM ) tool suite. Results suggest that when the SHIPMAIN process

  12. Flexible simulation framework to couple processes in complex 3D models for subsurface utilization assessment

    NASA Astrophysics Data System (ADS)

    Kempka, Thomas; Nakaten, Benjamin; De Lucia, Marco; Nakaten, Natalie; Otto, Christopher; Pohl, Maik; Tillner, Elena; Kühn, Michael

    2016-04-01

    Utilization of the geological subsurface for production and storage of hydrocarbons, chemical energy and heat as well as for waste disposal requires the quantification and mitigation of environmental impacts as well as the improvement of georesources utilization in terms of efficiency and sustainability. The development of tools for coupled process simulations is essential to tackle these challenges, since reliable assessments are only feasible by integrative numerical computations. Coupled processes at reservoir to regional scale determine the behaviour of reservoirs, faults and caprocks, generally demanding for complex 3D geological models to be considered besides available monitoring and experimenting data in coupled numerical simulations. We have been developing a flexible numerical simulation framework that provides efficient workflows for integrating the required data and software packages to carry out coupled process simulations considering, e.g., multiphase fluid flow, geomechanics, geochemistry and heat. Simulation results are stored in structured data formats to allow for an integrated 3D visualization and result interpretation as well as data archiving and its provision to collaborators. The main benefits in using the flexible simulation framework are the integration of data geological and grid data from any third party software package as well as data export to generic 3D visualization tools and archiving formats. The coupling of the required process simulators in time and space is feasible, while different spatial dimensions in the coupled simulations can be integrated, e.g., 0D batch with 3D dynamic simulations. User interaction is established via high-level programming languages, while computational efficiency is achieved by using low-level programming languages. We present three case studies on the assessment of geological subsurface utilization based on different process coupling approaches and numerical simulations.

  13. New 3D structuring process for non-integrated circuit related technologies (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Nouri, Lamia; Possémé, Nicolas; Landis, Stéfan; Milesi, Frédéric; Gaillard, Frédéric-Xavier

    2017-04-01

    Fabrication processes that microelectronic developed for Integrated circuit (IC) technologies for decades, do not meet the new emerging structuration's requirements, in particular non-IC related technologies one, such as MEMS/NEMS, Micro-Fluidics, photovoltaics, lenses. Actually complex 3D structuration requires complex lithography patterning approaches such as gray-scale electron beam lithography, laser ablation, focused ion beam lithography, two photon polymerization. It is now challenging to find cheaper and easiest technique to achieve 3D structures. In this work, we propose a straightforward process to realize 3D structuration, intended for silicon based materials (Si, SiN, SiOCH). This structuration technique is based on nano-imprint lithography (NIL), ion implantation and selective wet etching. In a first step a pattern is performed by lithography on a substrate, then ion implantation is realized through a resist mask in order to create localized modifications in the material, thus the pattern is transferred into the subjacent layer. Finally, after the resist stripping, a selective wet etching is carried out to remove selectively the modified material regarding the non-modified one. In this paper, we will first present results achieved with simple 2D line array pattern processed either on Silicon or SiOCH samples. This step have been carried out to demonstrate the feasibility of this new structuration process. SEM pictures reveals that "infinite" selectivity between the implanted areas versus the non-implanted one could be achieved. We will show that a key combination between the type of implanted ion species and wet etching chemistries is required to obtain such results. The mechanisms understanding involved during both implantation and wet etching processes will also be presented through fine characterizations with Photoluminescence, Raman and Secondary Ion Mass Spectrometry (SIMS) for silicon samples, and ellipso-porosimetry and Fourier Transform Infra

  14. Understanding Immersivity: Image Generation and Transformation Processes in 3D Immersive Environments

    PubMed Central

    Kozhevnikov, Maria; Dhond, Rupali P.

    2012-01-01

    Most research on three-dimensional (3D) visual-spatial processing has been conducted using traditional non-immersive 2D displays. Here we investigated how individuals generate and transform mental images within 3D immersive (3DI) virtual environments, in which the viewers perceive themselves as being surrounded by a 3D world. In Experiment 1, we compared participants’ performance on the Shepard and Metzler (1971) mental rotation (MR) task across the following three types of visual presentation environments; traditional 2D non-immersive (2DNI), 3D non-immersive (3DNI – anaglyphic glasses), and 3DI (head mounted display with position and head orientation tracking). In Experiment 2, we examined how the use of different backgrounds affected MR processes within the 3DI environment. In Experiment 3, we compared electroencephalogram data recorded while participants were mentally rotating visual-spatial images presented in 3DI vs. 2DNI environments. Overall, the findings of the three experiments suggest that visual-spatial processing is different in immersive and non-immersive environments, and that immersive environments may require different image encoding and transformation strategies than the two other non-immersive environments. Specifically, in a non-immersive environment, participants may utilize a scene-based frame of reference and allocentric encoding whereas immersive environments may encourage the use of a viewer-centered frame of reference and egocentric encoding. These findings also suggest that MR performed in laboratory conditions using a traditional 2D computer screen may not reflect spatial processing as it would occur in the real world. PMID:22908003

  15. Insights on the Subduction Process from High-Resolution 3D Models

    NASA Astrophysics Data System (ADS)

    Jadamec, Margarete

    2015-04-01

    This is an exciting time in geodynamics as the use of unprecedented high-resolution 3D modeling allows us to ask new questions that were previously unattainable. It is now relatively straightforward to run 3D numerical simulations, with local mesh refinement to ~1 km, input data mapped onto over 100 million finite element nodes, and using tens of thousands of compute hours per model, e.g. Jadamec et al. [2012]. With the additional computational resources, comes a new approach to modeling the tectonic problem. For example, mapping tectonic plates onto a high-resolution 3D geodynamic model grid forces the modeler to ask questions much as a field geologist would ask when constructing a geologic map. In this process of moving from textbook models of subduction to using models based on observation, the modeler is forced to explain the more complicated geometries and features in the Earth, allowing for the new computational approaches to be powerful tools for scientific discovery. Subduction modeling of this kind has expanded the classical view of two-dimensional corner flow, e.g. McKenzie [1969], to a slab driven flow that can be quite complex with predictions for upper mantle flow rates that can be over ten times surface plate motions, e.g. Jadamec et al. [2010] and others. In this talk, I will investigate the role of the third-dimension and non-linearity in plate boundary deformation. I will present high-resolution 3D numerical models that examine the effect of observationally based slab geometry, multiple subducting plates, non-linear rheology, and variations in overriding plate thickness on the subduction related deformation of plate margins. Specific examples include the Alaska and Central America subduction systems. In addition, I will highlight future directions in subduction modeling, and how these can be advanced by the increased incorporation of observational data, high-performance computing, focused numerical algorithms, and 3D interactive data visualization.

  16. A Process for Topographically Selective Deposition on 3D Nanostructures by Ion Implantation.

    PubMed

    Kim, Woo-Hee; Minaye Hashemi, Fatemeh Sadat; Mackus, Adriaan J M; Singh, Joseph; Kim, Yeongin; Bobb-Semple, Dara; Fan, Yin; Kaufman-Osborn, Tobin; Godet, Ludovic; Bent, Stacey F

    2016-04-26

    Area-selective atomic layer deposition (AS-ALD) is attracting increasing interest because of its ability to enable both continued dimensional scaling and accurate pattern placement for next-generation nanoelectronics. Here we report a strategy for depositing material onto three-dimensional (3D) nanostructures with topographic selectivity using an ALD process with the aid of an ultrathin hydrophobic surface layer. Using ion implantation of fluorocarbons (CFx), a hydrophobic interfacial layer is formed, which in turn causes significant retardation of nucleation during ALD. We demonstrate the process for Pt ALD on both blanket and 2D patterned substrates. We extend the process to 3D structures, demonstrating that this method can achieve selective anisotropic deposition, selectively inhibiting Pt deposition on deactivated horizontal regions while ensuring that only vertical surfaces are decorated during ALD. The efficacy of the approach for metal oxide ALD also shows promise, though further optimization of the implantation conditions is required. The present work advances practical applications that require area-selective coating of surfaces in a variety of 3D nanostructures according to their topographical orientation.

  17. 3D PLLA/ibuprofen composite scaffolds obtained by a supercritical fluids assisted process.

    PubMed

    Cardea, S; Baldino, L; Scognamiglio, M; Reverchon, E

    2014-04-01

    The emerging next generation of engineered tissues is based on the development of loaded scaffolds containing bioactive molecules in order to control the cellular function or to interact on the surrounding tissues. Indeed, implantation of engineered biomaterials might cause local inflammation because of the host's immune response; thereby, the use of anti-inflammatory agents, whether steroidal or nonsteroidal is required. One of the most important stages of tissue engineering is the design and the generation of a porous 3D structure, with high porosity, high interconnectivity and homogenous morphology. Various techniques have been reported in the literature for the fabrication of biodegradable scaffolds, but they suffer several limitations. In this study, for the first time, the possibility of generating 3D polymeric scaffolds loaded with an active compound by supercritical freeze extraction process is evaluated; this innovative process combines the advantages of the thermally induced phase separation process and of the supercritical carbon dioxide drying. Poly-L-lactid acid/ibuprofen composite scaffolds characterized by a 3D geometry, micrometric cellular structures and wrinkled pores walls have been obtained; moreover, homogeneous drug distribution and controlled release of the active principle have been assured.

  18. Optimization methods for 3D lithography process utilizing DMD-based maskless grayscale photolithography system

    NASA Astrophysics Data System (ADS)

    Ma, Xiaoxu; Kato, Yoshiki; Hirai, Yoshikazu; van Kempen, Floris; van Keulen, Fred; Tsuchiya, Toshiyuki; Tabata, Osamu

    2015-03-01

    Digital Micromirror Device (DMD)-based grayscale lithography is a promising tool for three dimensional (3D) microstructuring of thick-film photoresist since it is a maskless process, provides possibility for the free-form of 3D microstructures, and therefore rapid and cost-effective microfabrication. However, process parameter determination lacks efficient optimization tool, and thus conventional look-up table (indicating the relationship between development depth and exposure dose value under a fixed development time) approach with manual try-and-error adjustment is still gold standard. In this paper, we firstly present a complete "input target-output parameters" single exposure optimization method for 3D microstructuring utilizing DMD-based grayscale lithography. This numerical optimization based on lithography simulation and sensitivity analysis can automatically optimize a combination of three process parameters for target microstructure; exposure dose pattern, a focal position, and development time. Through a series of experiments using a 20 μm thick positive photoresist, validity of the proposed optimization approach has been successfully verified. Secondly, with the purpose of further advancing accuracy and improve the uniformity of precision for the target area, a multiple exposure optimization method is proposed. The simulated results proved that the multiple exposure optimization method is a promising strategy to further improve precision for thicker photoresist structure.

  19. Process monitor of 3D-device features by using FIB and CD-SEM

    NASA Astrophysics Data System (ADS)

    Kawada, Hiroki; Ikota, Masami; Sakai, Hideo; Torikawa, Shota; Tomimatsu, Satoshi; Onishi, Tsuyoshi

    2016-03-01

    For yield improvement of 3D-device manufacturing, metrology for the variability of individual device-features is on hot issue. Transmission Electron Microscope (TEM) can be used for monitoring the individual cross-section. However, efficiency of process monitoring is limited by the speed of measurement including preparation of lamella sample. In this work we demonstrate speedy 3D-profile measurement of individual line-features without the lamella sampling. For instance, we make a-few-micrometer-wide and 45-degree-descending slope in dense line-features by using Focused Ion Beam (FIB) tool capable of 300mm-wafer. On the descending slope, obliquely cut cross-section of the line features appears. Then, we transfer the wafer to Critical-Dimension Secondary Electron Microscope (CDSEM) to measure the oblique cross-section in normal top-down view. As the descending angle is 45 degrees, the oblique cross-section looks like a cross-section normal to the wafer surface. For every single line-features the 3D dimensions are measured. To the reference metrology of the Scanning TEM (STEM), nanometric linearity and precision are confirmed for the height and the width under the hard mask of the line features. Without cleaving wafer the 60 cells on the wafer can be measured in 3 hours, which allows us of near-line process monitor of in-wafer uniformity.

  20. 3D surface topography of cylinder liner forecasting during plateau honing process

    NASA Astrophysics Data System (ADS)

    Reizer, R.; Pawlus, P.

    2011-08-01

    Areal surface topographies after plateau honing process were measured. A correlation analysis of surface texture parameters was then carried out. As the results, the following parameters describing plateau honed cylinder 3D surface topography were selected: amplitude Sq, Sz, spatial: Str, Std, hybrid SΔq as well as functional: Spq, Svq and Smq. 3D surface topographies were modeled. The modeled surface topographies were correctly matched to measured ones in 77% of all analyzed cases. The plateau honing experiment was then carried out using an orthogonal selective research plan. Two machining parameters were input variables: coarse honing pressure pv and plateau honing time t. Chosen cylinder liners texture parameters were output values. As the result of the experiment, regression equations connecting plateau honing process parameters pv and t with recommended 3D surface topography parameters were obtained. Finally, cylinder liner surface topographies were predicted for various values of machining parameters. Proper matching accuracy of modeled to measured textures was assured in 67% of analyzed cases.

  1. 360 degree realistic 3D image display and image processing from real objects

    NASA Astrophysics Data System (ADS)

    Luo, Xin; Chen, Yue; Huang, Yong; Tan, Xiaodi; Horimai, Hideyoshi

    2016-12-01

    A 360-degree realistic 3D image display system based on direct light scanning method, so-called Holo-Table has been introduced in this paper. High-density directional continuous 3D motion images can be displayed easily with only one spatial light modulator. Using the holographic screen as the beam deflector, 360-degree full horizontal viewing angle was achieved. As an accompany part of the system, CMOS camera based image acquisition platform was built to feed the display engine, which can take a full 360-degree continuous imaging of the sample at the center. Customized image processing techniques such as scaling, rotation, format transformation were also developed and embedded into the system control software platform. In the end several samples were imaged to demonstrate the capability of our system.

  2. View planetary differentiation process through high-resolution 3D imaging

    NASA Astrophysics Data System (ADS)

    Fei, Y.

    2011-12-01

    Core-mantle separation is one of the most important processes in planetary evolution, defining the structure and chemical distribution in the planets. Iron-dominated core materials could migrate through silicate mantle to the core by efficient liquid-liquid separation and/or by percolation of liquid metal through solid silicate matrix. We can experimentally simulate these processes to examine the efficiency and time of core formation and its geochemical signatures. The quantitative measure of the efficiency of percolation is usually the dihedral angle, related to the interfacial energies of the liquid and solid phases. To determine the true dihedral angle at high pressure and temperatures, it is necessary to measure the relative frequency distributions of apparent dihedral angles between the quenched liquid metal and silicate grains for each experiment. Here I present a new imaging technique to visualize the distribution of liquid metal in silicate matrix in 3D by combination of focus ion beam (FIB) milling and high-resolution SEM image. The 3D volume rendering provides precise determination of the dihedral angle and quantitative measure of volume fraction and connectivity. I have conducted a series of experiments using mixtures of San Carlos olivine and Fe-S (10wt%S) metal with different metal-silicate ratios, up to 25 GPa and at temperatures above 1800C. High-quality 3D volume renderings were reconstructed from FIB serial sectioning and imaging with 10-nm slice thickness and 14-nm image resolution for each quenched sample. The unprecedented spatial resolution at nano scale allows detailed examination of textural features and precise determination of the dihedral angle as a function of pressure, temperature and composition. The 3D reconstruction also allows direct assessment of connectivity in multi-phase matrix, providing a new way to investigate the efficiency of metal percolation in a real silicate mantle.

  3. Mechanical performance of endodontic restorations with prefabricated posts: sensitivity analysis of parameters with a 3D finite element model.

    PubMed

    González-Lluch, Carmen; Pérez-González, Antonio; Sancho-Bru, Joaquín L; Rodríguez-Cervantes, Pablo-Jesús

    2014-08-01

    Many studies have investigated the effect of different parameters of the endodontically restored tooth on its final strength, using in vitro tests and model simulations. However, the differences in the experimental set-up or modelling conditions and the limited number of parameters studied in each case prevent us from obtaining clear conclusions about the relative importance of each parameter. In this study, a validated 3D biomechanical model of the restored tooth was used for an exhaustive sensitivity analysis. The individual influence of 20 different parameters on the mechanical performance of an endodontic restoration with prefabricated posts was studied. The results bring up the remarkable importance of the loading angle on the final restoration strength. Flexural loads are more critical than compressive or tensile loads. Young's modulus of the post and its length and diameter are the most influential parameters for strength, whereas other parameters such as ferrule geometry or core and crown characteristics are less significant.

  4. 3D Measurements of Ignition Processes at 20 kHz in a Supersonic Combustor

    DTIC Science & Technology

    2015-03-05

    1 3 DOI 10.1007/s00340-015-6066-4 Appl. Phys. B (2015) 119:313–318 3D measurements of ignition processes at 20 kHz in a supersonic combustor Lin Ma...also for the design of practical devices [1–3]. This work reports an experimental study of the ignition processes in supersonic (Mach 2) flows. Non...intrusive techniques are usually desired or required for experimental study in supersonic flows, and a range of opti- cal diagnostics has been

  5. The investigation of 193nm CPL 3D topology mask effect on wafer process performance

    NASA Astrophysics Data System (ADS)

    Cheng, Yung Feng; Chou, Yueh Lin; Yang, Chuen Huei

    2006-03-01

    As semiconductor process technology moves down below 90nm and 65nm, 193nm CPL (Chromeless Phase Lithography) technology becomes an important lithography strategy for process improvement on critical layers. In addition to the demand for very tight mask CD control, for a dry-etched process, there are two critical factors that can have significant impact on wafer CD control and window performance. They are etch-depth control (phase) through feature pitch and overall etching slope profile. Both affect image quality and the final overlapped process window. In this paper, we will study the effect of a 3D topology mask on the process window and wafer CD by making special 193nm CPL masks and printing them on 300mm wafers under a production-manufacturing environment. These masks had been specially designed with different sidewall angles and different etch depths (phase). There are 4 different quartz etch depths and 3 different sidewall angles for specially designed test patterns that are compatible with the 65nm technology node. They are printed on 300mm wafers by using a high NA ASML 193nm scanner and high contrast resist. In order to establish more effective specifications of phase and profile control on 193nm CPL between mask shops and wafer fabs, all AFM, wafer CD, and simulation results will be compared and correlated. By comparing the wafer CD and pattern profile on through focus conditions, we can understand the impact of phase and 3D mask profile on process performance.

  6. Context-adaptive based CU processing for 3D-HEVC

    PubMed Central

    Shen, Liquan; An, Ping; Liu, Zhi

    2017-01-01

    The 3D High Efficiency Video Coding (3D-HEVC) standard aims to code 3D videos that usually contain multi-view texture videos and its corresponding depth information. It inherits the same quadtree prediction structure of HEVC to code both texture videos and depth maps. Each coding unit (CU) allows recursively splitting into four equal sub-CUs. At each CU depth level, it enables 10 types of inter modes and 35 types of intra modes in inter frames. Furthermore, the inter-view prediction tools are applied to each view in the test model of 3D-HEVC (HTM), which uses variable size disparity-compensated prediction to exploit inter-view correlation within neighbor views. It also exploits redundancies between a texture video and its associated depth using inter-component coding tools. These achieve the highest coding efficiency to code 3D videos but require a very high computational complexity. In this paper, we propose a context-adaptive based fast CU processing algorithm to jointly optimize the most complex components of HTM including CU depth level decision, mode decision, motion estimation (ME) and disparity estimation (DE) processes. It is based on the hypothesis that the optimal CU depth level, prediction mode and motion vector of a CU are correlated with those from spatiotemporal, inter-view and inter-component neighboring CUs. We analyze the video content based on coding information from neighboring CUs and early predict each CU into one of five categories i.e., DE-omitted CU, ME-DE-omitted CU, SPLIT CU, Non-SPLIT CU and normal CU, and then each type of CU adaptively adopts different processing strategies. Experimental results show that the proposed algorithm saves 70% encoder runtime on average with only a 0.1% BD-rate increase on coded views and 0.8% BD-rate increase on synthesized views. Our algorithm outperforms the state-of-the-art algorithms in terms of coding time saving or with better RD performance. PMID:28182719

  7. 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.

  8. An Integrated Multi-component Processing and Interpretation Framework for 3D Borehole Seismic Data

    SciTech Connect

    M. Karrenbach

    2004-04-01

    This report covers the October 2003 until March 2004 time period. Work has continued successfully on several tasks 1 through 7. Most of these tasks have been executed independently. Due to availability of manpower during that time period we progressed steadily and completed some of the tasks, while others are still on going. We achieved the goals that we had set up in the task schedule. Reviewing the results of this work period indicates that our plan is on schedule and we did not encounter any unforeseen problems. The work plan will continue as projected. Several independent tasks pursuant the statement of project objectives have been executed simultaneously and are still on-going. This report summarizes the selection, test processing and test flow generation of a relevant 3D borehole seismic high-resolution test dataset. This multi-component data set is suitable for future use in this project due to data quality and unique acquisition characteristics. This report shows initial processing results that supported the data selection scheduled for Task 1. Use of real data is augmented by the creating a 3D layered synthetic geologic model in which multi-component 3D borehole seismic data were generated using 3D ray tracing. A gridded surface representation of the reflection interfaces as well as fully populated velocity grids were generated and archived. The model consists of a moderately dipping geologic setting with horizon undulations. A realistic velocity variation is used in between the three layers. Acquisition was simulated from a set of equidistant source locations at the surface of the model, while a close to vertical VSP well was used to capture the wave field data. The source pattern was close to a staggered grid pattern. Multi-component particle displacements were recorded every 50 ft down with an array length of 4,000 ft. P-P as well as P-S reflections were specified in the resulting wave field. We ensured a large enough aperture with enough fine sampling

  9. Tachycardia in post-infarction hearts: insights from 3D image-based ventricular models.

    PubMed

    Arevalo, Hermenegild; Plank, Gernot; Helm, Patrick; Halperin, Henry; Trayanova, Natalia

    2013-01-01

    Ventricular tachycardia, a life-threatening regular and repetitive fast heart rhythm, frequently occurs in the setting of myocardial infarction. Recently, the peri-infarct zones surrounding the necrotic scar (termed gray zones) have been shown to correlate with ventricular tachycardia inducibility. However, it remains unknown how the latter is determined by gray zone distribution and size. The goal of this study is to examine how tachycardia circuits are maintained in the infarcted heart and to explore the relationship between the tachycardia organizing centers and the infarct gray zone size and degree of heterogeneity. To achieve the goals of the study, we employ a sophisticated high-resolution electrophysiological model of the infarcted canine ventricles reconstructed from imaging data, representing both scar and gray zone. The baseline canine ventricular model was also used to generate additional ventricular models with different gray zone sizes, as well as models in which the gray zone was represented as different heterogeneous combinations of viable tissue and necrotic scar. The results of the tachycardia induction simulations with a number of high-resolution canine ventricular models (22 altogether) demonstrated that the gray zone was the critical factor resulting in arrhythmia induction and maintenance. In all models with inducible arrhythmia, the scroll-wave filaments were contained entirely within the gray zone, regardless of its size or the level of heterogeneity of its composition. The gray zone was thus found to be the arrhythmogenic substrate that promoted wavebreak and reentry formation. We found that the scroll-wave filament locations were insensitive to the structural composition of the gray zone and were determined predominantly by the gray zone morphology and size. The findings of this study have important implications for the advancement of improved criteria for stratifying arrhythmia risk in post-infarction patients and for the development of

  10. Spheroidization by Plasma Processing and Characterization of Stainless Steel Powder for 3D Printing

    NASA Astrophysics Data System (ADS)

    Ji, Lina; Wang, Changzhen; Wu, Wenjie; Tan, Chao; Wang, Guoyu; Duan, Xuan-Ming

    2017-10-01

    Stainless steel 316L (SS 316L) powder was spheroidized by plasma processing to improve its suitability for powder 3D printing. The obtained spheroidized (sphero) powder was characterized in terms of its crystalline phases, elemental composition, morphology, particle size and distribution, light absorption, and flow properties. The elemental composition of the sphero powder met the Chinese standard for SS 316L except for its Si content. The volume fraction of ferrite increased after plasma processing. Furthermore, plasma processing was shown to not only reduce the mean size of the particles in the size range of 10 to 100 μm but also generate particles in the size range of 0.1 to 10 μm. The smaller particles filled the voids among larger particles, increasing the powder density. The light absorption was also increased owing to enhanced internal reflection. Although the basic flow energy decreased after plasma processing, the flow function (FF) value was smaller for the sphero powder, indicating a lower flowability of the sphero powder. However, the density of SS 316L pieces printed with commercial and sphero powders was 98.76 pct and 98.16 pct of the SS 316L bulk density, respectively, indicating the suitability of the sphero powder for 3D printing despite an FF below 10.

  11. Process development for high-resolution 3D-printing of bioresorbable vascular stents

    NASA Astrophysics Data System (ADS)

    Ware, Henry Oliver T.; Farsheed, Adam C.; van Lith, Robert; Baker, Evan; Ameer, Guillermo; Sun, Cheng

    2017-02-01

    The recent development of "continuous projection microstereolithography" also known as CLIP technology has successfully alleviated the main obstacles surrounding 3D printing technologies: production speed and part quality. Following the same working principle, we further developed the μCLIP process to address the needs for high-resolution 3D printing of biomedical devices with micron-scale precision. Compared to standard stereolithography (SLA) process, μCLIP fabrication can reduce fabrication time from several hours to as little as a few minutes. μCLIP can also produce better surface finish and more uniform mechanical properties than conventional SLA, as each individual "fabrication layer" continuously polymerizes into the subsequent layer. In this study, we report the process development in manufacturing high-resolution bioresorbable stents using our own μCLIP system. The bioresorbable photopolymerizable biomaterial (B-ink) used in this study is methacrylated poly(1, 12 dodecamethylene citrate) (mPDC). Through optimization of our μCLIP process and concentration of B-ink components, we have created a customizable bioresorbable stent with similar mechanical properties exhibited by nitinol stents. Upon optimization, fabricating a 2 cm tall vascular stent that comprises 4000 layers was accomplished in 26.5 minutes.

  12. Electromagnetic and absorbing property of CIPs/resin composite using the 3D forming process

    NASA Astrophysics Data System (ADS)

    Xu, Yonggang; Liang, Zichang; Wang, Xiaobing; Yuan, Liming; Li, Xinghao

    2016-08-01

    The absorbing composite filled with the flaky carbonyl iron particles (CIPs) were prepared using a three-dimensional (3D) forming process, in which the forming powder was fabricated using a milling process. The surface morphology was characterized by the scanning electron microscopy, the static magnetic property was evaluated on a vibrating sample magnetometer, and X-ray diffraction (XRD) patterns were done to analyze the particle crystal grain structure. The complex permittivity and permeability were measured using a vector network analyzer in the frequency range of 4-18 GHz. With the variable thickness was set, the reflection loss (RL) was simulated to analyze the absorbing property of the composite. The results showed that the forming powder was uniformly dispersed in the absorber, and the saturation magnetization and the grain structure of the CIPs in the forming powder nearly did not change in the milling process. With the same volume content CIPs added, the average permittivity and the imaginary permeability of the samples added the powder was smaller than the directly mixing sample due to the aggregation effect. The RL results showed that the absorbing composites using the 3D forming process with thickness 6 or 8 mm had an better absorbing property (minimum RL -13.58 and -21.85 dB) in 4-18 GHz.

  13. In vivo multiphoton microscopy associated to 3D image processing for human skin characterization

    NASA Astrophysics Data System (ADS)

    Baldeweck, T.; Tancrède, E.; Dokladal, P.; Koudoro, S.; Morard, V.; Meyer, F.; Decencière, E.; Pena, A.-M.

    2012-03-01

    Multiphoton microscopy has emerged in the past decade as a promising non-invasive skin imaging technique. The aim of this study was to assess whether multiphoton microscopy coupled to specific 3D image processing tools could provide new insights into the organization of different skin components and their age-related changes. For that purpose, we performed a clinical trial on 15 young and 15 aged human female volunteers on the ventral and dorsal side of the forearm using the DermaInspectR medical imaging device. We visualized the skin by taking advantage of intrinsic multiphoton signals from cells, elastic and collagen fibers. We also developed 3D image processing algorithms adapted to in vivo multiphoton images of human skin in order to extract quantitative parameters in each layer of the skin (epidermis and superficial dermis). The results show that in vivo multiphoton microscopy is able to evidence several skin alterations due to skin aging: morphological changes in the epidermis and modifications in the quantity and organization of the collagen and elastic fibers network. In conclusion, the association of multiphoton microscopy with specific image processing allows the three-dimensional organization of skin components to be visualized and quantified thus providing a powerful tool for cosmetic and dermatological investigations.

  14. 3D Finite Element Analysis of Spider Non-isothermal Forging Process

    NASA Astrophysics Data System (ADS)

    Niu, Ling; Wei, Wei; Wei, Kun Xia; Alexandrov, Igor V.; Hu, Jing

    2016-06-01

    The differences of effective stress, effective strain, velocity field, and the load-time curves between the spider isothermal and non-isothermal forging processes are investigated by making full use of 3D FEA, and verified by the production experiment of spider forging. Effective stress is mainly concentrated on the pin, and becomes lower closer to the front of the pin. The maximum effective strain in the non-isothermal forging is lower than that in the isothermal. The great majority of strain in the non-isothermal forging process is 1.76, which is larger than the strain of 1.31 in the isothermal forging. The maximum load required in the isothermal forging is higher than that in the non-isothermal. The maximum experimental load and deformation temperature in the spider production are in good agreement with those in the non-isothermal FEA. The results indicate that the non-isothermal 3D FEA results can guide the design of the spider forging process.

  15. A 3-D nonisothermal flow simulation and pulling force model for injection pultrusion processes

    NASA Astrophysics Data System (ADS)

    Mustafa, Ibrahim

    1998-12-01

    Injected Pultrusion (IP) is an efficient way of producing high quality, low cost, high volume and constant cross-section polymeric composites. This process has been developed recently, and the efforts to optimize it are still underway. This work is related to the development of a 3-D non-isothermal flow model for the IP processes. The governing equations for transport of mass, momentum and, energy are formulated by using a local volume averaging approach, and the Finite Element/Control Volume method is used to solve the system of equations numerically. The chemical species balance equation is solved in the Lagrangian frame of reference whereas the energy equation is solved using Galerkin, SU (Streamline Upwind), and SUPG (Streamline Upwind Petrov Galerkin) approaches. By varying degrees of freedom and the flow rates of the resin, it is shown that at high Peclet numbers the SUPG formulation performs better than the SU and the Galerkin methods in all cases. The 3-D model predictions for degree of cure and temperature are compared with a one dimensional analytical solution and the results are found satisfactory. Moreover, by varying the Brinkman Number, it is shown that the effect of viscous dissipation is insignificant. The 3-D flow simulations have been carried out for both thin and thick parts and the results are compared with the 2-D model. It is shown that for thick parts 2-D simulations render erroneous results. The effect of changing permeability on the flow fronts is also addressed. The effect of increasing taper angle on the model prediction is also investigated. A parametric study is conducted to isolate optimum conditions for both isothermal and non-isothermal cases using a straight rectangular die and a die with a tapered inlet. Finally, a simple pulling force model is developed and the pulling force required to pull the carbon-epoxy fiber resin system is estimated for dies of varying tapered inlet.

  16. 3D interpretation of SHARAD radargram data using seismic processing routines

    NASA Astrophysics Data System (ADS)

    Kleuskens, M. H. P.; Oosthoek, J. H. P.

    2009-04-01

    engineering software package Petrel of Schlumberger to interpret the radar data in 3D, using its powerful seismic interpretation tool. Since the radardata does not contain an absolute vertical time reference, the surface reflection in the radargram is referenced to the Mars Orbiter Laser Altimeter (MOLA) topography data of the region. By doing this, we can visualize all radar traces in 3D and interpret the combined 3D dataset altogether. Furthermore, MOLA and high resolution satellite images can be projected simultaneously in Petrel as a reference. This method gives much more insight in the data than analyzing each 2D radargram individually: an anomaly that is spotted in a 2D radargram can be validated by a radargram that is positioned perpendicular to the first one. This method helps us to distinguish between different layers and detect instrument and cross-track anomalies. Furthermore, we can perform automatic analyses such as estimating volumes of different formations. This helps us to understand the formation process of the ice cap.

  17. Post-mortem computed tomography and 3D imaging: anthropological applications for juvenile remains.

    PubMed

    Brough, Alison L; Rutty, Guy N; Black, Sue; Morgan, Bruno

    2012-09-01

    Anthropological examination of defleshed bones is routinely used in medico-legal investigations to establish an individual's biological profile. However, when dealing with the recently deceased, the removal of soft tissue from bone can be an extremely time consuming procedure that requires the presence of a trained anthropologist. In addition, due to its invasive nature, in some disaster victim identification scenarios the maceration of bones is discouraged by religious practices and beliefs, or even prohibited by national laws and regulations. Currently, three different radiological techniques may be used in the investigative process; plain X-ray, dental X-ray and fluoroscopy. However, recent advances in multi-detector computed tomography (MDCT) mean that it is now possible to acquire morphological skeletal information from high resolution images, reducing the necessity for invasive procedures. This review paper considers the possible applications of a virtual anthropological examination by reviewing the main juvenile age determination methods used by anthropologists at present and their possible adaption to MDCT.

  18. Fabrication and Characterization of 3D-Printed Highly-Porous 3D LiFePO₄ Electrodes by Low Temperature Direct Writing Process.

    PubMed

    Liu, Changyong; Cheng, Xingxing; Li, Bohan; Chen, Zhangwei; Mi, Shengli; Lao, Changshi

    2017-08-10

    LiFePO₄ (LFP) is a promising cathode material for lithium-ion batteries. In this study, low temperature direct writing (LTDW)-based 3D printing was used to fabricate three-dimensional (3D) LFP electrodes for the first time. LFP inks were deposited into a low temperature chamber and solidified to maintain the shape and mechanical integrity of the printed features. The printed LFP electrodes were then freeze-dried to remove the solvents so that highly-porous architectures in the electrodes were obtained. LFP inks capable of freezing at low temperature was developed by adding 1,4 dioxane as a freezing agent. The rheological behavior of the prepared LFP inks was measured and appropriate compositions and ratios were selected. A LTDW machine was developed to print the electrodes. The printing parameters were optimized and the printing accuracy was characterized. Results showed that LTDW can effectively maintain the shape and mechanical integrity during the printing process. The microstructure, pore size and distribution of the printed LFP electrodes was characterized. In comparison with conventional room temperature direct ink writing process, improved pore volume and porosity can be obtained using the LTDW process. The electrochemical performance of LTDW-fabricated LFP electrodes and conventional roller-coated electrodes were conducted and compared. Results showed that the porous structure that existed in the printed electrodes can greatly improve the rate performance of LFP electrodes.

  19. Fabrication and Characterization of 3D-Printed Highly-Porous 3D LiFePO4 Electrodes by Low Temperature Direct Writing Process

    PubMed Central

    Cheng, Xingxing; Li, Bohan; Chen, Zhangwei; Mi, Shengli; Lao, Changshi

    2017-01-01

    LiFePO4 (LFP) is a promising cathode material for lithium-ion batteries. In this study, low temperature direct writing (LTDW)-based 3D printing was used to fabricate three-dimensional (3D) LFP electrodes for the first time. LFP inks were deposited into a low temperature chamber and solidified to maintain the shape and mechanical integrity of the printed features. The printed LFP electrodes were then freeze-dried to remove the solvents so that highly-porous architectures in the electrodes were obtained. LFP inks capable of freezing at low temperature was developed by adding 1,4 dioxane as a freezing agent. The rheological behavior of the prepared LFP inks was measured and appropriate compositions and ratios were selected. A LTDW machine was developed to print the electrodes. The printing parameters were optimized and the printing accuracy was characterized. Results showed that LTDW can effectively maintain the shape and mechanical integrity during the printing process. The microstructure, pore size and distribution of the printed LFP electrodes was characterized. In comparison with conventional room temperature direct ink writing process, improved pore volume and porosity can be obtained using the LTDW process. The electrochemical performance of LTDW-fabricated LFP electrodes and conventional roller-coated electrodes were conducted and compared. Results showed that the porous structure that existed in the printed electrodes can greatly improve the rate performance of LFP electrodes. PMID:28796182

  20. Web-based interactive 2D/3D medical image processing and visualization software.

    PubMed

    Mahmoudi, Seyyed Ehsan; Akhondi-Asl, Alireza; Rahmani, Roohollah; Faghih-Roohi, Shahrooz; Taimouri, Vahid; Sabouri, Ahmad; Soltanian-Zadeh, Hamid

    2010-05-01

    There are many medical image processing software tools available for research and diagnosis purposes. However, most of these tools are available only as local applications. This limits the accessibility of the software to a specific machine, and thus the data and processing power of that application are not available to other workstations. Further, there are operating system and processing power limitations which prevent such applications from running on every type of workstation. By developing web-based tools, it is possible for users to access the medical image processing functionalities wherever the internet is available. In this paper, we introduce a pure web-based, interactive, extendable, 2D and 3D medical image processing and visualization application that requires no client installation. Our software uses a four-layered design consisting of an algorithm layer, web-user-interface layer, server communication layer, and wrapper layer. To compete with extendibility of the current local medical image processing software, each layer is highly independent of other layers. A wide range of medical image preprocessing, registration, and segmentation methods are implemented using open source libraries. Desktop-like user interaction is provided by using AJAX technology in the web-user-interface. For the visualization functionality of the software, the VRML standard is used to provide 3D features over the web. Integration of these technologies has allowed implementation of our purely web-based software with high functionality without requiring powerful computational resources in the client side. The user-interface is designed such that the users can select appropriate parameters for practical research and clinical studies.

  1. Experimental and Numerical Investigation of Forging Process to Reproduce a 3D Aluminium Foam Complex Shape

    SciTech Connect

    Filice, Luigino; Gagliardi, Francesco; Umbrello, Domenico; Shivpuri, Rajiv

    2007-05-17

    Metallic foams represent one of the most exciting materials introduced in the manufacturing scenario in the last years. In the study here addressed, the experimental and numerical investigations on the forging process of a simple foam billet shaped into complex sculptured parts were carried out. In particular, the deformation behavior of metallic foams and the development of density gradients were investigated through a series of experimental forging tests in order to produce a selected portion of a hip prosthesis. The human bone replacement was chosen as case study due to its industrial demand and for its particular 3D complex shape. A finite element code (Deform 3D) was utilized for modeling the foam behavior during the forging process and an accurate material rheology description was used based on a porous material model which includes the measured local density. Once the effectiveness of the utilized Finite Element model was verified through the comparison with the experimental evidences, a numerical study of the influence of the foam density was investigated. The obtained numerical results shown as the initial billet density plays an important role on the prediction of the final shape, the optimization of the flash as well as the estimation of the punch load.

  2. 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.

  3. GPR data processing for 3D fracture mapping in a marble quarry (Thassos, Greece)

    NASA Astrophysics Data System (ADS)

    Grandjean, G.; Gourry, J. C.

    1996-11-01

    Ground Penetrating Radar (GPR) has been successfully applied to detect and map fractures in marble quarries. The aim was to distinguish quickly intact marketable marble areas from fractured ones in order to improve quarry management. The GPR profiling method was chosen because it is non destructive and quickly provides a detailed image of the subsurface. It was performed in domains corresponding to future working areas in real quarry-exploitation conditions. Field surveying and data processing were adapted to the local characteristics of the fractures: E-W orientation, sub-vertical dip, and karst features. After the GPR profiles had been processed, using methods adapted from seismics (amplitude compensation, filtering and Fourier migration), the interpreted fractures from a 12 × 24 × 15 m zone were incorporated into a 3D model. Due to the low electrical conductivity of the marble, GPR provides penetration depths of about 8 and 15 m, and resolutions of about 1 and 5 cm for frequencies of 900 and 300 MHz respectively. The detection power thus seems to be sufficient to recommend use of this method. As requested by the quarriers, the 3D representation can be used directly by themselves to locate high- or low-quality marble areas. Comparison between the observed surface fractures and the fractures detected using GPR showed reasonable correlation.

  4. Source Process of the 1923 Kanto Earthquake Using New Fault Geometry and 3-D Green's Functions

    NASA Astrophysics Data System (ADS)

    Kobayashi, R.; Koketsu, K.

    2005-12-01

    The September 1, 1923, Kanto earthquake caused severe damage and more than 100,000 fatalities in the Tokyo metropolitan area. This earthquake is an interplate event along the Sagami trough where the Philippine Sea plate is subducting beneath a continental plate. We have investigated the source process of this earthquake using the geodetic, teleseismic, and strong motion data (Kobayashi and Koketsu, 2005). The resultant slip distributions show that two asperities (areas of large slips) are located around the base of the Izu peninsula and the Uraga channel. In 2002 and 2003, four seismic surveys were carried out to determine crustal structures and fault locations in the Kanto region (Sato et al., 2005). The seismic reflections from the surface of the Philippine Sea slab suggested that the slab surface should be shallower than the previous models (e.g., Ishida, 1992; Matsu'ura et al., 1980). The fault model of Kobayashi and Koketsu (2005) was also based on Matsu'ura et al. (1980). In this study, we adopt new fault geometry consistent with the result of the reflection surveys and perform another source process inversion. The new slip distribution showed that the western asperity moved from the Uraga channel to the tip of the Miura peninsula, while the western asperity did not move considerably. Green's functions that Kobayashi and Koketsu (2005) used were calculated in a halfspace for geodetic data or in a 1-D model for strong motions. However, the real structure in the Kanto region is three-dimensionally complex as suggested by the geographical setting and seismic surveys. In fact, Kobayashi and Koketsu (2005) showed that the long coda of the observed seismogram at Hongo, Tokyo, was not reproduced in the synthetic one. The forward modeling with a 3-D structure (Sato et al., 1999) suggested that surface waves excited along the boundary between the Kanto mountains and Kanto basin can explain the large coda. Thus we calculate 3-D Green's functions for the strong motion

  5. Percolation properties of 3-D multiscale pore networks: how connectivity controls soil filtration processes

    NASA Astrophysics Data System (ADS)

    Perrier, E. M. A.; Bird, N. R. A.; Rieutord, T. B.

    2010-10-01

    Quantifying the connectivity of pore networks is a key issue not only for modelling fluid flow and solute transport in porous media but also for assessing the ability of soil ecosystems to filter bacteria, viruses and any type of living microorganisms as well inert particles which pose a contamination risk. Straining is the main mechanical component of filtration processes: it is due to size effects, when a given soil retains a conveyed entity larger than the pores through which it is attempting to pass. We postulate that the range of sizes of entities which can be trapped inside soils has to be associated with the large range of scales involved in natural soil structures and that information on the pore size distribution has to be complemented by information on a critical filtration size (CFS) delimiting the transition between percolating and non percolating regimes in multiscale pore networks. We show that the mass fractal dimensions which are classically used in soil science to quantify scaling laws in observed pore size distributions can also be used to build 3-D multiscale models of pore networks exhibiting such a critical transition. We extend to the 3-D case a new theoretical approach recently developed to address the connectivity of 2-D fractal networks (Bird and Perrier, 2009). Theoretical arguments based on renormalisation functions provide insight into multi-scale connectivity and a first estimation of CFS. Numerical experiments on 3-D prefractal media confirm the qualitative theory. These results open the way towards a new methodology to estimate soil filtration efficiency from the construction of soil structural models to be calibrated on available multiscale data.

  6. Percolation properties of 3-D multiscale pore networks: how connectivity controls soil filtration processes

    NASA Astrophysics Data System (ADS)

    Perrier, E. M. A.; Bird, N. R. A.; Rieutord, T. B.

    2010-04-01

    Quantifying the connectivity of pore networks is a key issue not only for modelling fluid flow and solute transport in porous media but also for assessing the ability of soil ecosystems to filter bacteria, viruses and any type of living microorganisms as well inert particles which pose a contamination risk. Straining is the main mechanical component of filtration processes: it is due to size effects, when a given soil retains a conveyed entity larger than the pores through which it is attempting to pass. We postulate that the range of sizes of entities which can be trapped inside soils has to be associated with the large range of scales involved in natural soil structures and that information on the pore size distribution has to be complemented by information on a Critical Filtration Size (CFS) delimiting the transition between percolating and non percolating regimes in multiscale pore networks. We show that the mass fractal dimensions which are classically used in soil science to quantify scaling laws in observed pore size distributions can also be used to build 3-D multiscale models of pore networks exhibiting such a critical transition. We extend to the 3-D case a new theoretical approach recently developed to address the connectivity of 2-D fractal networks (Bird and Perrier, 2009). Theoretical arguments based on renormalisation functions provide insight into multi-scale connectivity and a first estimation of CFS. Numerical experiments on 3-D prefractal media confirm the qualitative theory. These results open the way towards a new methodology to estimate soil filtration efficiency from the construction of soil structural models to be calibrated on available multiscale data.

  7. 3-D synthetic aperture processing on high-frequency wide-beam microwave systems

    NASA Astrophysics Data System (ADS)

    Cristofani, Edison; Brook, Anna; Vandewal, Marijke

    2012-06-01

    The use of High-Frequency MicroWaves (HFMW) for high-resolution imagery has gained interest over the last years. Very promising in-depth applications can be foreseen for composite non-metal, non-polarized materials, widely used in the aeronautic and aerospace industries. Most of these materials present a high transparency in the HFMW range and, therefore, defects, delaminations or occlusions within the material can be located. This property can be exploited by applying 3-D HFMW imaging where conventional focused imaging systems are typically used but a different approach such as Synthetic Aperture (SA) radar can be addressed. This paper will present an end-to-end 3-D imagery system for short-range, non-destructive testing based on a frequency-modulated continuous-wave HFMWsensor operating at 100 GHz, implying no health concerns to the human body as well as relatively low cost and limited power requirements. The sensor scans the material while moving sequentially in every elevation plane following a 2-D grid and uses a significantly wide beam antenna for data acquisition, in contrast to focused systems. Collected data must be coherently combined using a SA algorithm to form focused images. Range-independent, synthetically improved cross-range resolutions are remarkable added values of SA processing. Such algorithms can be found in the literature and operate in the time or frequency domains, being the former computationally impractical and the latter the best option for in-depth 3-D imaging. A balanced trade-off between performance and image focusing quality is investigated for several SA algorithms.

  8. Processing 3D flash LADAR point-clouds in real-time for flight applications

    NASA Astrophysics Data System (ADS)

    Craig, R.; Gravseth, I.; Earhart, R. P.; Bladt, J.; Barnhill, S.; Ruppert, L.; Centamore, C.

    2007-04-01

    Ball Aerospace & Technologies Corp. has demonstrated real-time processing of 3D imaging LADAR point-cloud data to produce the industry's first time-of-flight (TOF) 3D video capability. This capability is uniquely suited to the rigorous demands of space and airborne flight applications and holds great promise in the area of autonomous navigation. It will provide long-range, three dimensional video information to autonomous flight software or pilots for immediate use in rendezvous and docking, proximity operations, landing, surface vision systems, and automatic target recognition and tracking. This is enabled by our new generation of FPGA based "pixel-tube" processors, coprocessors and their associated algorithms which have led to a number of advancements in high-speed wavefront processing along with additional advances in dynamic camera control, and space laser designs based on Ball's CALIPSO LIDAR. This evolution in LADAR is made possible by moving the mechanical complexity required for a scanning system into the electronics, where production, integration, testing and life-cycle costs can be significantly reduced. This technique requires a state of the art TOF read-out integrated circuit (ROIC) attached to a sensor array to collect high resolution temporal data, which is then processed through FPGAs. The number of calculations required to process the data is greatly reduced thanks to the fact that all points are captured at the same time and thus correlated. This correlation allows extremely efficient FPGA processing. This capability has been demonstrated in prototype form at both Marshal Space Flight Center and Langley Research Center on targets that represent docking and landing scenarios. This report outlines many aspects of this work as well as aspects of our recent testing at Marshall's Flight Robotics Laboratory.

  9. 3-D earthquake surface displacements from differencing pre- and post-event LiDAR point clouds

    NASA Astrophysics Data System (ADS)

    Krishnan, A. K.; Nissen, E.; Arrowsmith, R.; Saripalli, S.

    2012-12-01

    The explosion in aerial LiDAR surveying along active faults across the western United States and elsewhere provides a high-resolution topographic baseline against which to compare repeat LiDAR datasets collected after future earthquakes. We present a new method for determining 3-D coseismic surface displacements and rotations by differencing pre- and post-earthquake LiDAR point clouds using an adaptation of the Iterative Closest Point (ICP) algorithm, a point set registration technique widely used in medical imaging, computer vision and graphics. There is no need for any gridding or smoothing of the LiDAR data and the method works well even with large mismatches in the density of the two point clouds. To explore the method's performance, we simulate pre- and post-event point clouds using real ("B4") LiDAR data on the southern San Andreas Fault perturbed with displacements of known magnitude. For input point clouds with ~2 points per square meter, we are able to reproduce displacements with a 50 m grid spacing and with horizontal and vertical accuracies of ~20 cm and ~4 cm. In the future, finer grids and improved precisions should be possible with higher shot densities and better survey geo-referencing. By capturing near-fault deformation in 3-D, LiDAR differencing with ICP will complement satellite-based techniques such as InSAR which map only certain components of the surface deformation and which often break down close to surface faulting or in areas of dense vegetation. It will be especially useful for mapping shallow fault slip and rupture zone deformation, helping inform paleoseismic studies and better constrain fault zone rheology. Because ICP can image rotations directly, the technique will also help resolve the detailed kinematics of distributed zones of faulting where block rotations may be common.

  10. In Situ 3D Synchrotron Imaging of Failure Processes in Engineering Materials

    NASA Astrophysics Data System (ADS)

    Mostafijur Rahman, K. M.; Szpunar, Jerzy; Belev, George

    2013-03-01

    The micrometer range resolution of Synchrotron Radiation Tomography has developed an important technique for characterizing the three dimensional (3D) microstructure of materials. This technique was used for imaging Aluminum-alumina composites, porous aluminum and AA 6061 alloy under different loading conditions. The experimental set-up was installed at the Biomedical Imaging and Therapy (BMIT)'s 05B1-1 beamline at Canadian Light Source (CLS). The experimental stage has been designed for conducting the in-situ experiments. The unique feature of this experimental stage is that the sample can be rotated torsion free for taking the images for Computed Tomography imaging during any loading conditions. The developed experimental system and technique allows deciphering the internal structures of composites, porous materials, multiphase alloys and to observe the failure processes such as crack initiation, crack propagation, void formation, void coalescence and the fracture process during loading of materials.

  11. 3D display and image processing system for metal bellows welding

    NASA Astrophysics Data System (ADS)

    Park, Min-Chul; Son, Jung-Young

    2010-04-01

    Industrial welded metal Bellows is in shape of flexible pipeline. The most common form of bellows is as pairs of washer-shaped discs of thin sheet metal stamped from strip stock. Performing arc welding operation may cause dangerous accidents and bad smells. Furthermore, in the process of welding operation, workers have to observe the object directly through microscope adjusting the vertical and horizontal positions of welding rod tip and the bellows fixed on the jig, respectively. Welding looking through microscope makes workers feel tired. To improve working environment that workers sit in an uncomfortable position and productivity we introduced 3D display and image processing. Main purpose of the system is not only to maximize the efficiency of industrial productivity with accuracy but also to keep the safety standards with the full automation of work by distant remote controlling.

  12. Photoresist 3D profile related etch process simulation and its application to full chip etch compact modeling

    NASA Astrophysics Data System (ADS)

    Wu, Cheng-En; Yang, Wayne; Luan, Lan; Song, Hua

    2015-03-01

    The optical proximity correction (OPC) model and post-OPC verification that takes the developed photoresist (PR) 3D profile into account is needed in the advanced 2Xnm node. The etch process hotspots caused by poor resist profile may not be fully identified during the lithography inspection but will only be observed after the subsequent etch process. A complete mask correction that targets to final etch CD requires not only a lithography R3D profile model but also a etch process compact model. The drawback of existing etch model is to treat the etch CD bias as a function of visibility and pattern density which do not contain the information of resist profile. One important factor to affect the etch CD is the PR lateral erosion during the etch process due to non-vertical PR side wall angle (SWA) and anisotropy of etch plasma source. A simple example is in transferring patterns from PR layer to thin hard mask (HM) layer, which is frequently used in the double pattern (DPT) process. The PR lateral erosion contributes an extra HM etch CD bias which is deviated from PR CD defined by lithography process. This CD bias is found to have a nontrivial dependency on the PR profile and cannot be described by the pattern density or visibility. In this report, we study the etch CD variation to resist SWA under various etch conditions. Physical effects during etch process such as plasma ion reflection and source anisotropy, which modify the local etch rate, are taken into considerations in simulation. The virtual data are generated by Synopsys TCAD tool Sentaurus Topography 3D using Monte Carlo engine. A simple geometry compact model is applied first to explain the behavior of virtual data, however, it works to some extent but lacks accuracy when plasma ion reflection comes into play. A modified version is proposed, for the first time, by including the effects of plasma ion reflection and source anisotropy. The new compact model fits the nonlinear etch CD bias very well for a wide

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

    NASA Astrophysics Data System (ADS)

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

    2014-05-01

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

  14. a Semi-Automated Point Cloud Processing Methodology for 3d Cultural Heritage Documentation

    NASA Astrophysics Data System (ADS)

    Kıvılcım, C. Ö.; Duran, Z.

    2016-06-01

    The preliminary phase in any architectural heritage project is to obtain metric measurements and documentation of the building and its individual elements. On the other hand, conventional measurement techniques require tremendous resources and lengthy project completion times for architectural surveys and 3D model production. Over the past two decades, the widespread use of laser scanning and digital photogrammetry have significantly altered the heritage documentation process. Furthermore, advances in these technologies have enabled robust data collection and reduced user workload for generating various levels of products, from single buildings to expansive cityscapes. More recently, the use of procedural modelling methods and BIM relevant applications for historic building documentation purposes has become an active area of research, however fully automated systems in cultural heritage documentation still remains open. In this paper, we present a semi-automated methodology, for 3D façade modelling of cultural heritage assets based on parametric and procedural modelling techniques and using airborne and terrestrial laser scanning data. We present the contribution of our methodology, which we implemented in an open source software environment using the example project of a 16th century early classical era Ottoman structure, Sinan the Architect's Şehzade Mosque in Istanbul, Turkey.

  15. Photopolymerization of 3D conductive polypyrrole structures via digital light processing

    NASA Astrophysics Data System (ADS)

    Price, Aaron D.

    2016-04-01

    The intrinsically conductive polymer polypyrrole is conventionally synthesized as monolithic films that exhibit significant actuation strains when subjected to an applied electric potential. Though numerous linear and bending actuators based on polypyrrole films have been investigated, the limitations inherent to planar film geometries inhibit the realization of more complex behaviours. Hence, three-dimensional polypyrrole structures are sought to greatly expand the potential applications for conductive polymer actuators. This research aims to develop a novel additive manufacturing method for the fabrication of three-dimensional structures of conductive polypyrrole. In this investigation, radiation-curing techniques are employed by means of digital light processing (DLP) technology. DLP is an additive manufacturing technique where programmed light patterns emitted from a dedicated source are used to selectively cure a specially formulated polymer resin. Successive curing operations lead to a layered 3D structure into which fine features may be incorporated. Energy dispersive spectroscopy (EDS) is subsequently employed to examine the unique microstructural features of the resultant 3D printed polymer morphology in order to elucidate the nature of the conductivity. These polymer microstructures are highly desirable since actuation response times are highly dependent on ion transport distances, and hence the ability to fabricate fine features offers a potential mechanism to improve actuator performance.

  16. Filters in 2D and 3D Cardiac SPECT Image Processing.

    PubMed

    Lyra, Maria; Ploussi, Agapi; Rouchota, Maritina; Synefia, Stella

    2014-01-01

    Nuclear cardiac imaging is a noninvasive, sensitive method providing information on cardiac structure and physiology. Single photon emission tomography (SPECT) evaluates myocardial perfusion, viability, and function and is widely used in clinical routine. The quality of the tomographic image is a key for accurate diagnosis. Image filtering, a mathematical processing, compensates for loss of detail in an image while reducing image noise, and it can improve the image resolution and limit the degradation of the image. SPECT images are then reconstructed, either by filter back projection (FBP) analytical technique or iteratively, by algebraic methods. The aim of this study is to review filters in cardiac 2D, 3D, and 4D SPECT applications and how these affect the image quality mirroring the diagnostic accuracy of SPECT images. Several filters, including the Hanning, Butterworth, and Parzen filters, were evaluated in combination with the two reconstruction methods as well as with a specified MatLab program. Results showed that for both 3D and 4D cardiac SPECT the Butterworth filter, for different critical frequencies and orders, produced the best results. Between the two reconstruction methods, the iterative one might be more appropriate for cardiac SPECT, since it improves lesion detectability due to the significant improvement of image contrast.

  17. Filters in 2D and 3D Cardiac SPECT Image Processing

    PubMed Central

    Ploussi, Agapi; Synefia, Stella

    2014-01-01

    Nuclear cardiac imaging is a noninvasive, sensitive method providing information on cardiac structure and physiology. Single photon emission tomography (SPECT) evaluates myocardial perfusion, viability, and function and is widely used in clinical routine. The quality of the tomographic image is a key for accurate diagnosis. Image filtering, a mathematical processing, compensates for loss of detail in an image while reducing image noise, and it can improve the image resolution and limit the degradation of the image. SPECT images are then reconstructed, either by filter back projection (FBP) analytical technique or iteratively, by algebraic methods. The aim of this study is to review filters in cardiac 2D, 3D, and 4D SPECT applications and how these affect the image quality mirroring the diagnostic accuracy of SPECT images. Several filters, including the Hanning, Butterworth, and Parzen filters, were evaluated in combination with the two reconstruction methods as well as with a specified MatLab program. Results showed that for both 3D and 4D cardiac SPECT the Butterworth filter, for different critical frequencies and orders, produced the best results. Between the two reconstruction methods, the iterative one might be more appropriate for cardiac SPECT, since it improves lesion detectability due to the significant improvement of image contrast. PMID:24804144

  18. Processing of noised residual stress phase maps by using a 3D phase unwrapping algorithm

    NASA Astrophysics Data System (ADS)

    Viotti, Matias R.; Fantin, Analucia V.; Albertazzi, Armando; Willemann, Daniel P.

    2013-07-01

    The measurement of residual stress by using digital speckle pattern interferometry (DSPI) combined with the hole drilling technique is a valuable and fast tool for integrity evaluation of civil structures and mechanical parts. However, in some cases, measured phase maps are badly corrupted by noise which makes phase unwrapping a difficult and unsuccessful task. By following recommendations given by the ASTM E837 standard, 20 consecutive hole steps should be performed for the measurement of non-uniform stresses. As a consequence, 20 difference phase maps along the hole depth will be available for the DSPI technique. An adaptive phase unwrapping algorithm could be used in order to unwrap images following paths localized along well modulated pixels and performing two dimensional phase unwrapping (following paths inside a difference phase map corresponding to a hole step) or 3D phase unwrapping (similar to a temporal phase unwrapping following paths located at well-modulated pixels in a previous or a subsequent hole image). Non-corrupted and corrupted hole-drilling tests were processed with a traditional phase unwrapping algorithm as well as with the proposed 3D approach. Comparisons between unwrapped phase maps and simulated ones have shown that the proposed method gave results with best accordance than 2D results.

  19. 3D numerical simulation of the evolutionary process of aeolian downsized crescent-shaped dunes

    NASA Astrophysics Data System (ADS)

    Zhou, Xiaosi; Zhang, Yang; Wang, Yuan; Li, Min

    2016-06-01

    A dune constitutive model was coupled with a large eddy simulation (LES) with the Smagorinsky subgrid-scale (SGS) model to accurately describe the evolutionary process of dunes from the macroscopic perspective of morphological dynamics. A 3D numerical simulation of the evolution of aeolian downsized crescent-shaped dunes was then performed. The evolution of the 3D structure of Gaussian-shaped dunes was simulated under the influence of gravity modulation, which was the same with the vertical oscillation of the sand bed to adjust the threshold of sand grain liftoff in wind tunnel experiments under the same wind speed. The influence of gravity modulation intensity on the characteristic scale parameter of the dune was discussed. Results indicated that the crescent shape of the dune was reproduced with the action of gravity during regulation of the saturation of wind-sand flow at specific times. The crescent shape was not dynamically maintained as time passed, and the dunes dwindled until they reached final decomposition because of wind erosion. The height of the dunes decreased over time, and the height-time curve converged as the intensity of modulation increased linearly. The results qualitatively agreed with those obtained from wind tunnel experiments.

  20. Simulation of metal forming processes with a 3D adaptive remeshing procedure

    NASA Astrophysics Data System (ADS)

    Zeramdini, Bessam; Robert, Camille; Germain, Guenael; Pottier, Thomas

    2016-10-01

    In this paper, a fully adaptive 3D numerical methodology based on a tetrahedral element was proposed in order to improve the finite element simulation of any metal forming process. This automatic methodology was implemented in a computational platform which integrates a finite element solver, 3D mesh generation and a field transfer algorithm. The proposed remeshing method was developed in order to solve problems associated with the severe distortion of elements subject to large deformations, to concentrate the elements where the error is large and to coarsen the mesh where the error is small. This leads to a significant reduction in the computation times while maintaining simulation accuracy. In addition, in order to enhance the contact conditions, this method has been coupled with a specific operator to maintain the initial contact between the workpiece nodes and the rigid tool after each remeshing step. In this paper special attention is paid to the data transfer methods and the necessary adaptive remeshing steps are given. Finally, a numerical example is detailed to demonstrate the efficiency of the approach and to compare the results for the different field transfer strategies.

  1. Fabrication of solution processed 3D nanostructured CuInGaS₂ thin film solar cells.

    PubMed

    Chu, Van Ben; Cho, Jin Woo; Park, Se Jin; Hwang, Yun Jeong; Park, Hoo Keun; Do, Young Rag; Min, Byoung Koun

    2014-03-28

    In this study we demonstrate the fabrication of CuInGaS₂ (CIGS) thin film solar cells with a three-dimensional (3D) nanostructure based on indium tin oxide (ITO) nanorod films and precursor solutions (Cu, In and Ga nitrates in alcohol). To obtain solution processed 3D nanostructured CIGS thin film solar cells, two different precursor solutions were applied to complete gap filling in ITO nanorods and achieve the desirable absorber film thickness. Specifically, a coating of precursor solution without polymer binder material was first applied to fill the gap between ITO nanorods followed by deposition of the second precursor solution in the presence of a binder to generate an absorber film thickness of ∼1.3 μm. A solar cell device with a (Al, Ni)/AZO/i-ZnO/CdS/CIGS/ITO nanorod/glass structure was constructed using the CIGS film, and the highest power conversion efficiency was measured to be ∼6.3% at standard irradiation conditions, which was 22.5% higher than the planar type of CIGS solar cell on ITO substrate fabricated using the same precursor solutions.

  2. Magnetic source imaging (MSI) in children with neocortical epilepsy: surgical outcome association with 3D post-resection analysis.

    PubMed

    Kim, Hyunmi; Kankirawatana, Pongkiat; Killen, Jeff; Harrison, Allan; Oh, Ahyuda; Rozzelle, Curtis; Blount, Jeffrey; Knowlton, Robert

    2013-09-01

    To investigate the validity of magnetic source imaging (MSI) to localize seizure-onset zone using 3D analysis of pre-operative MSI source imaging coregistered to post-resection MRI following neocortical epilepsy surgery. Twenty-two children who had MSI and epilepsy surgery were studied (median age=11 years, 1 year 2 months-22 years). Only seven (31.8%) had localized lesions on pre-operative conventional brain MRIs. Sixteen (72.7%) underwent intracranial EEG monitoring. Mean post-operative follow-up was 4.7 years (1 year 3 months-8 years 2 months). Fifteen patients (68%) were seizure-free. MEG spike dipole sources were superimposed onto post-operative MRIs. The number and proportion of spike dipoles within resection volume were calculated and compared between seizure free and non-free groups. Both number of dipole clusters and proportion of dipoles in resection volume were not associated with seizure-free outcome (p>0.05). In seven cases with MRI lesions, six of these with a ≥70% dipoles within the resection margin were seizure-free, while one with the proportion <70% was not seizure-free. Further, among the 15 cases with non-localized or normal MRI, five with both the proportion <70% and multiple dipoles clusters were post-operatively seizure free. Number and density of clustered spike dipole sources within the surgical resection volume is not associated with postoperative seizure-free outcome. MSI successfully localized the perilesional epileptogenic zone in cases with localized MRI lesions, but not in cases with normal MRI in this study. Even if MEG localizes spikes to a single focal region, confirmation of epilepsy localization with intracranial EEG is still recommended in cases with non-lesional MRI. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Developing a 3D Game Design Authoring Package to Assist Students' Visualization Process in Design Thinking

    ERIC Educational Resources Information Center

    Kuo, Ming-Shiou; Chuang, Tsung-Yen

    2013-01-01

    The teaching of 3D digital game design requires the development of students' meta-skills, from story creativity to 3D model construction, and even the visualization process in design thinking. The characteristics a good game designer should possess have been identified as including redesign things, creativity thinking and the ability to…

  4. Developing a 3D Game Design Authoring Package to Assist Students' Visualization Process in Design Thinking

    ERIC Educational Resources Information Center

    Kuo, Ming-Shiou; Chuang, Tsung-Yen

    2013-01-01

    The teaching of 3D digital game design requires the development of students' meta-skills, from story creativity to 3D model construction, and even the visualization process in design thinking. The characteristics a good game designer should possess have been identified as including redesign things, creativity thinking and the ability to…

  5. Advanced time-of-flight range camera with novel real-time 3D image processing

    NASA Astrophysics Data System (ADS)

    Koenig, Bernhard; Hosticka, Bedrich; Mengel, Peter; Listl, Ludwig

    2007-09-01

    We present a solid state range camera covering measuring distances from 2 m to 25 m and novel real-time 3D image processing algorithms for object detection, tracking and classification based on the three-dimensional features of the camera's output data. The technology is based on a 64x8 pixel array CMOS image sensor which is capable of capturing three-dimensional images by executing indirect time-of-flight (ToF) measurement of NIR laser pulses emitted by the camera and reflected by the objects in the cameras field of view. Here the so-called "multiple double short time integration" (MDSI) method enables unprecedented reliability and robustness with respect to suppression of background irradiance and insensitiveness to reflectivity variations in the object scene. Output data are conventional intensity values and distance values with accuracies in the centimeter range at image repetition rates up to 100 Hz. An evaluation of the camera's performance in typical road safety related test scenarios is subject of this paper. Furthermore we introduce real-time image processing of the output data stream of the camera aiming at the segmentation of objects being located in the camera's surrounding and the derivation of reliable position, speed and acceleration estimates. The segmentation algorithm utilizes the position information of all three spatial dimensions as well as the intensity values and thus yields significant segmentation improvement compared to segmentation in conventional 2D pictures. Position, velocity and acceleration values of the segmented objects are estimated by means of Kalman filtering in 3D space. The filter is dynamically adapting to the measurement conditions to take care of changes of the scene data properties. Flow and performance of the whole processing chain are presented by means of example scenes.

  6. Simulation of bacteria transport processes in a river with Flow3D

    NASA Astrophysics Data System (ADS)

    Schwarzwälder, Kordula; Bui, Minh Duc; Rutschmann, Peter

    2014-05-01

    Water quality aspects are getting more and more important due to the European water Framework directive (WFD). One problem related to this topic is the inflow of untreated wastewater due to combined sewer overflows into a river. The wastewater mixture contains even bacteria like E. coli and Enterococci which are markers for water quality. In our work we investigated the transport of these bacteria in river Isar by using a large-scale flume in the outside area of our lab (Oskar von Miller Institute). Therefor we could collect basic data and knowledge about the processes which occur during bacteria sedimentation and remobilisation. In our flume we could use the real grain with the exact size distribution curve as in the river Isar which we want to simulate and we had the chance to nurture a biofilm which is realistic for the analysed situation. This biofilm plays an important role in the remobilisation processes, because the bacteria are hindered to be washed out back into the bulk phase as fast and in such an amount as this would happen without biofilm. The results of our experiments are now used for a module in the 3D software Flow3D to simulate the effects of a point source inlet of raw wastewater on the water quality. Therefor we have to implement the bacteria not as a problem of concentration with advection and diffusion but as single particles which can be inactivated during the process of settling and need to be hindered from remobilisation by the biofilm. This biofilm has special characteristic, it is slippery and has a special thickness which influences the chance of bacteria being removed. To achieve realistic results we have to include the biofilm with more than a probabilistic-tool to make sure that our module is transferable. The module should be as flexible as possible to be improved step by step with increasing quality of dataset.

  7. 3D modelling of coupled mass and heat transfer of a convection-oven roasting process.

    PubMed

    Feyissa, Aberham Hailu; Gernaey, Krist V; Adler-Nissen, Jens

    2013-04-01

    A 3D mathematical model of coupled heat and mass transfer describing oven roasting of meat has been developed from first principles. The proposed mechanism for the mass transfer of water is modified and based on a critical literature review of the effect of heat on meat. The model equations are based on a conservation of mass and energy, coupled through Darcy's equations of porous media - the water flow is mainly pressure-driven. The developed model together with theoretical and experimental assessments were used to explain the heat and water transport and the effect of the change in microstructure (permeability, water binding capacity and elastic modulus) that occur during the meat roasting process. The developed coupled partial differential equations were solved by using COMSOL Multiphysics®3.5 and state variables are predicted as functions of both position and time. The proposed mechanism was partially validated by experiments in a convection oven where temperatures were measured online.

  8. 3D Seismic Experimentation and Advanced Processing/Inversion Development for Investigations of the Shallow Subsurface

    SciTech Connect

    Levander, Alan Richard; Zelt, Colin A.

    2015-03-17

    The work plan for this project was to develop and apply advanced seismic reflection and wide-angle processing and inversion techniques to high resolution seismic data for the shallow subsurface to seismically characterize the shallow subsurface at hazardous waste sites as an aid to containment and cleanup activities. We proposed to continue work on seismic data that we had already acquired under a previous DoE grant, as well as to acquire additional new datasets for analysis. The project successfully developed and/or implemented the use of 3D reflection seismology algorithms, waveform tomography and finite-frequency tomography using compressional and shear waves for high resolution characterization of the shallow subsurface at two waste sites. These two sites have markedly different near-surface structures, groundwater flow patterns, and hazardous waste problems. This is documented in the list of refereed documents, conference proceedings, and Rice graduate theses, listed below.

  9. 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.

  10. 3D template fabrication process for the dual damascene NIL approach

    NASA Astrophysics Data System (ADS)

    Butschke, Joerg; Irmscher, Mathias; Resnick, Douglas; Sailer, Holger; Thompson, Ecron

    2007-05-01

    NIL technique enables an easy replication of three dimensional patterns. Combined with a UV printable low-k material the NIL lithography can dramatically simplify the dual damascene process. Goal of this work was to develop a template process scheme which enables the generation of high resolution pillars on top of corresponding lines for direct printing of later vias and metal lines. The process flow is based on conventional 6025 photomask blanks. Exposure was done on a variable shaped e-beam writer Vistec SB350 using a sample of an advanced negative tone CAR and Fujifilm pCAR FEP171 for the first and the second layer, respectively. Chrome and quartz etching was accomplished in an Oerlikon mask etcher Gen III and Gen IV. Assessment of the developed template process was done in terms of overlay accuracy, feature profile and resolution capability depending on aspect ratio and line duty cycle. Finally the printability of 3D templates fabricated according the developed process scheme was proved.

  11. 3D MEMS in Standard Processes: Fabrication, Quality Assurance, and Novel Measurement Microstructures

    NASA Technical Reports Server (NTRS)

    Lin, Gisela; Lawton, Russell A.

    2000-01-01

    Three-dimensional MEMS microsystems that are commercially fabricated require minimal post-processing and are easily integrated with CMOS signal processing electronics. Measurements to evaluate the fabrication process (such as cross-sectional imaging and device performance characterization) provide much needed feedback in terms of reliability and quality assurance. MEMS technology is bringing a new class of microscale measurements to fruition. The relatively small size of MEMS microsystems offers the potential for higher fidelity recordings compared to macrosize counterparts, as illustrated in the measurement of muscle cell forces.

  12. 3-D image pre-processing algorithms for improved automated tracing of neuronal arbors.

    PubMed

    Narayanaswamy, Arunachalam; Wang, Yu; Roysam, Badrinath

    2011-09-01

    The accuracy and reliability of automated neurite tracing systems is ultimately limited by image quality as reflected in the signal-to-noise ratio, contrast, and image variability. This paper describes a novel combination of image processing methods that operate on images of neurites captured by confocal and widefield microscopy, and produce synthetic images that are better suited to automated tracing. The algorithms are based on the curvelet transform (for denoising curvilinear structures and local orientation estimation), perceptual grouping by scalar voting (for elimination of non-tubular structures and improvement of neurite continuity while preserving branch points), adaptive focus detection, and depth estimation (for handling widefield images without deconvolution). The proposed methods are fast, and capable of handling large images. Their ability to handle images of unlimited size derives from automated tiling of large images along the lateral dimension, and processing of 3-D images one optical slice at a time. Their speed derives in part from the fact that the core computations are formulated in terms of the Fast Fourier Transform (FFT), and in part from parallel computation on multi-core computers. The methods are simple to apply to new images since they require very few adjustable parameters, all of which are intuitive. Examples of pre-processing DIADEM Challenge images are used to illustrate improved automated tracing resulting from our pre-processing methods.

  13. Design methodology: edgeless 3D ASICs with complex in-pixel processing for pixel detectors

    SciTech Connect

    Fahim Farah, Fahim Farah; Deptuch, Grzegorz W.; Hoff, James R.; Mohseni, Hooman

    2015-08-28

    The design methodology for the development of 3D integrated edgeless pixel detectors with in-pixel processing using Electronic Design Automation (EDA) tools is presented. A large area 3 tier 3D detector with one sensor layer and two ASIC layers containing one analog and one digital tier, is built for x-ray photon time of arrival measurement and imaging. A full custom analog pixel is 65μm x 65μm. It is connected to a sensor pixel of the same size on one side, and on the other side it has approximately 40 connections to the digital pixel. A 32 x 32 edgeless array without any peripheral functional blocks constitutes a sub-chip. The sub-chip is an indivisible unit, which is further arranged in a 6 x 6 array to create the entire 1.248cm x 1.248cm ASIC. Each chip has 720 bump-bond I/O connections, on the back of the digital tier to the ceramic PCB. All the analog tier power and biasing is conveyed through the digital tier from the PCB. The assembly has no peripheral functional blocks, and hence the active area extends to the edge of the detector. This was achieved by using a few flavors of almost identical analog pixels (minimal variation in layout) to allow for peripheral biasing blocks to be placed within pixels. The 1024 pixels within a digital sub-chip array have a variety of full custom, semi-custom and automated timing driven functional blocks placed together. The methodology uses a modified mixed-mode on-top digital implementation flow to not only harness the tool efficiency for timing and floor-planning but also to maintain designer control over compact parasitically aware layout. The methodology uses the Cadence design platform, however it is not limited to this tool.

  14. Tropical Oceanic Precipitation Processes over Warm Pool: 2D and 3D Cloud Resolving Model Simulations

    NASA Technical Reports Server (NTRS)

    Tao, W.- K.; Johnson, D.

    1998-01-01

    stratiform regions; (3) the cloud (upward-downward) mass fluxes in convective and stratiform regions; (4) characteristics of clouds (such as cloud size, updraft intensity and cloud lifetime) and the comparison of clouds with Radar observations. Differences and similarities in organization of convection between simulated 2D and 3D cloud systems. Preliminary results indicated that there is major differences between 2D and 3D simulated stratiform rainfall amount and convective updraft and downdraft mass fluxes.

  15. Tropical Oceanic Precipitation Processes over Warm Pool: 2D and 3D Cloud Resolving Model Simulations

    NASA Technical Reports Server (NTRS)

    Tao, W.- K.; Johnson, D.

    1998-01-01

    stratiform regions; (3) the cloud (upward-downward) mass fluxes in convective and stratiform regions; (4) characteristics of clouds (such as cloud size, updraft intensity and cloud lifetime) and the comparison of clouds with Radar observations. Differences and similarities in organization of convection between simulated 2D and 3D cloud systems. Preliminary results indicated that there is major differences between 2D and 3D simulated stratiform rainfall amount and convective updraft and downdraft mass fluxes.

  16. Feature extraction from 3D lidar point clouds using image processing methods

    NASA Astrophysics Data System (ADS)

    Zhu, Ling; Shortridge, Ashton; Lusch, David; Shi, Ruoming

    2011-10-01

    Airborne LiDAR data have become cost-effective to produce at local and regional scales across the United States and internationally. These data are typically collected and processed into surface data products by contractors for state and local communities. Current algorithms for advanced processing of LiDAR point cloud data are normally implemented in specialized, expensive software that is not available for many users, and these users are therefore unable to experiment with the LiDAR point cloud data directly for extracting desired feature classes. The objective of this research is to identify and assess automated, readily implementable GIS procedures to extract features like buildings, vegetated areas, parking lots and roads from LiDAR data using standard image processing tools, as such tools are relatively mature with many effective classification methods. The final procedure adopted employs four distinct stages. First, interpolation is used to transfer the 3D points to a high-resolution raster. Raster grids of both height and intensity are generated. Second, multiple raster maps - a normalized surface model (nDSM), difference of returns, slope, and the LiDAR intensity map - are conflated to generate a multi-channel image. Third, a feature space of this image is created. Finally, supervised classification on the feature space is implemented. The approach is demonstrated in both a conceptual model and on a complex real-world case study, and its strengths and limitations are addressed.

  17. Finite element simulation of HIP-process to produce 3d near net shape parts

    SciTech Connect

    Zadeh, M.K.

    1996-12-31

    One of the major problems when producing powder metallurgy parts through hot isostatic pressing (HIP) is the non homogeneous shrinkage of HIP-capsule during the process. This leads to time and cost consuming machining of the HIP parts. In order to reduce the machining to a minimum, one can try to simulate the HIP-process by means of numerical methods. Hereby, the part distortion can be predicted, and hence a new HIP-capsule can be designed in such a way to prevent the distortion partly or even completely. In the following, a finite element method is used, on one hand, to simulate part shrinkage during HIP process; on the other hand a method is integrated in this simulation to optimize the HIP-capsule geometry. For the determination of material dependent parameters, a mixture of theoretical and experimental methods is used. Results of simulation are verified for a complex 3d HIP part out of TiAl6V4.

  18. A novel lithography process for 3D (three-dimensional) interconnect using an optical direct-writing exposure system

    NASA Astrophysics Data System (ADS)

    Azuma, T.; Sekiguchi, M.; Matsuo, M.; Kawasaki, A.; Hagiwara, K.; Matsui, H.; Kawamura, N.; Kishimoto, K.; Nakamura, A.; Washio, Y.

    2010-03-01

    A novel lithography process for 3D (Three-dimensional) interconnect was developed using an optical direct-writing exposure tool. A reflective IR (Infra-red) alignment system allows a direct detection of alignment marks both on front-side and back-side of wafer, and consequently allows feasible micro-fabrication for 3D interconnect using the reversed wafer. A combination of the optical direct-writing exposure tool of Dainippon Screen MFG. Co., Ltd. with the reflective IR alignment system and a high aspect chemically amplified resist of Tokyo Ohka Kogyo Co., Ltd. provides the lithography process exclusively for 12-inch wafer level 3D interconnect.

  19. Adaptive Iterative Dose Reduction Using Three Dimensional Processing (AIDR3D) Improves Chest CT Image Quality and Reduces Radiation Exposure

    PubMed Central

    Yamashiro, Tsuneo; Miyara, Tetsuhiro; Honda, Osamu; Kamiya, Hisashi; Murata, Kiyoshi; Ohno, Yoshiharu; Tomiyama, Noriyuki; Moriya, Hiroshi; Koyama, Mitsuhiro; Noma, Satoshi; Kamiya, Ayano; Tanaka, Yuko; Murayama, Sadayuki

    2014-01-01

    Objective To assess the advantages of Adaptive Iterative Dose Reduction using Three Dimensional Processing (AIDR3D) for image quality improvement and dose reduction for chest computed tomography (CT). Methods Institutional Review Boards approved this study and informed consent was obtained. Eighty-eight subjects underwent chest CT at five institutions using identical scanners and protocols. During a single visit, each subject was scanned using different tube currents: 240, 120, and 60 mA. Scan data were converted to images using AIDR3D and a conventional reconstruction mode (without AIDR3D). Using a 5-point scale from 1 (non-diagnostic) to 5 (excellent), three blinded observers independently evaluated image quality for three lung zones, four patterns of lung disease (nodule/mass, emphysema, bronchiolitis, and diffuse lung disease), and three mediastinal measurements (small structure visibility, streak artifacts, and shoulder artifacts). Differences in these scores were assessed by Scheffe's test. Results At each tube current, scans using AIDR3D had higher scores than those without AIDR3D, which were significant for lung zones (p<0.0001) and all mediastinal measurements (p<0.01). For lung diseases, significant improvements with AIDR3D were frequently observed at 120 and 60 mA. Scans with AIDR3D at 120 mA had significantly higher scores than those without AIDR3D at 240 mA for lung zones and mediastinal streak artifacts (p<0.0001), and slightly higher or equal scores for all other measurements. Scans with AIDR3D at 60 mA were also judged superior or equivalent to those without AIDR3D at 120 mA. Conclusion For chest CT, AIDR3D provides better image quality and can reduce radiation exposure by 50%. PMID:25153797

  20. Understanding surface processes 3D imaging from micro-scale to regional scale

    NASA Astrophysics Data System (ADS)

    Jaboyedoff, Michel; Abellan, Antonio; Carrea, Dario; Derron, Marc-Henri; Franz, Martin; Guerin, Antoine; Humair, Florian; Matasci, Battista; Michoud, Clément; Nicolet, Pierrick; Penna, Ivanna; Rudaz, Benjamin; Voumard, Jeremie; Wyser, Emmanuel

    2015-04-01

    The production of topography using remote sensing techniques has considerably been improved during the last fifteen years due to the advances in electronics and to the increase of computing power. The earth surface is monitored at all the scales using Space Shuttle Missions (SRTM) digital elevation model (DEM), or using laser scanner (LS), both terrestrial (TLS) and airborne (ALS), with accuracies that can reach up to less than 50 microns for observations of objects at meter scale. Recently, photogrammetry has been pushed by the progress of LiDAR and thanks to the advance in image recognition. It led to the development of new techniques such as structure-from-motion (SFM), which allows obtaining 3D point cloud based on several pictures of the same object taken from several point of views. Both LiDAR and Photogrammetry produce 3D point clouds. One of the current 3D applications is the surface changes, which is often based simply on the subtraction of DEM at different time intervals, leading to a simple superficial description of the natural processes without information on the mass transport. However, a point cloud has much more information than a simple surface. For instance, shape recognition can be used to track objects or deformations such as a rock mass toppling, either using the shape of the point cloud or a specific moving element. Such method permits, for instance, to study in detail pre-failure accelerations, and are now routinely used in mining industry. Other methods are coupling images and DEMs and are used, for example, to capture the surface vectors of displacements in order to deduce the surface deformations of landslides. These types of surveys have now broad applications to all kinds of erosional processes. The coastal retreat can be monitored, and it displays in some places several centimetres per year of retreat on average. The sediment transports in torrent are now better constraint showing clearly pulses. The seasonal cycles can as well be

  1. 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.

  2. Acquisition of high-resolution 3D data and processing using Artificial Intelligence

    NASA Astrophysics Data System (ADS)

    Meng, Hui; Sheng, J.; Yang, W.; Pu, Y.

    1996-11-01

    Holographic PIV (HPIV) is a promising 3D velocity field measurement technique providing high spatial-temporal resolution needed for understanding complex and turbulent flows. An HPIV system, combining in-line recording and off-axis viewing (IROV) holography and Heuristic Morphology Particle Pairing (HMPP) method, is being developed in this work. Unlike 2D PIV, HPIV instantaneously records a volume of particle images through holographic imaging. Its data processing involves special difficulties such as speckle noise, sparse pairs and large data sets. The HMPP algorithm is an adaptive parallel processing scheme applying artificial intelligence searching theory. Based on similar morphology of a particle group at successive instants separated by a small interval, HMPP matches a group of particle images between double exposures and provides velocity vectors for individual particle pairs, providing much higher spatial resolution than conventional correlation algorithm and lower measurement error caused by large velocity gradients. Taking advantages of IROV and HMPP, the system being developed appears highly promising as a practical HPIV configuration.

  3. Experimental and Numerical Investigation of Forging Process to Reproduce a 3D Aluminium Foam Complex Shape

    NASA Astrophysics Data System (ADS)

    Filice, Luigino; Gagliardi, Francesco; Shivpuri, Rajiv; Umbrello, Domenico

    2007-05-01

    Metallic foams represent one of the most exciting materials introduced in the manufacturing scenario in the last years. In the study here addressed, the experimental and numerical investigations on the forging process of a simple foam billet shaped into complex sculptured parts were carried out. In particular, the deformation behavior of metallic foams and the development of density gradients were investigated through a series of experimental forging tests in order to produce a selected portion of a hip prosthesis. The human bone replacement was chosen as case study due to its industrial demand and for its particular 3D complex shape. A finite element code (Deform 3D®) was utilized for modeling the foam behavior during the forging process and an accurate material rheology description was used based on a porous material model which includes the measured local density. Once the effectiveness of the utilized Finite Element model was verified through the comparison with the experimental evidences, a numerical study of the influence of the foam density was investigated. The obtained numerical results shown as the initial billet density plays an important role on the prediction of the final shape, the optimization of the flash as well as the estimation of the punch load.

  4. A T1 and DTI fused 3D corpus callosum analysis in pre- vs. post-season contact sports players

    NASA Astrophysics Data System (ADS)

    Lao, Yi; Law, Meng; Shi, Jie; Gajawelli, Niharika; Haas, Lauren; Wang, Yalin; Leporé, Natasha

    2015-01-01

    Sports related traumatic brain injury (TBI) is a worldwide public health issue, and damage to the corpus callosum (CC) has been considered as an important indicator of TBI. However, contact sports players suffer repeated hits to the head during the course of a season even in the absence of diagnosed concussion, and less is known about their effect on callosal anatomy. In addition, T1-weighted and diffusion tensor brain magnetic resonance images (DTI) have been analyzed separately, but a joint analysis of both types of data may increase statistical power and give a more complete understanding of anatomical correlates of subclinical concussions in these athletes. Here, for the first time, we fuse T1 surface-based morphometry and a new DTI analysis on 3D surface representations of the CCs into a single statistical analysis on these subjects. Our new combined method successfully increases detection power in detecting differences between pre- vs. post-season contact sports players. Alterations are found in the ventral genu, isthmus, and splenium of CC. Our findings may inform future health assessments in contact sports players. The new method here is also the first truly multimodal diffusion and T1-weighted analysis of the CC, and may be useful to detect anatomical changes in the corpus callosum in other multimodal datasets.

  5. 3D tissue culture substrates produced by microthermoforming of pre-processed polymer films.

    PubMed

    Giselbrecht, S; Gietzelt, T; Gottwald, E; Trautmann, C; Truckenmüller, R; Weibezahn, K F; Welle, A

    2006-09-01

    We describe a new technology based on thermoforming as a microfabrication process. It significantly enhances the tailoring of polymers for three dimensional tissue engineering purposes since for the first time highly resolved surface and bulk modifications prior to a microstructuring process can be realised. In contrast to typical micro moulding techniques, the melting phase is avoided and thus allows the forming of pre-processed polymer films. The polymer is formed in a thermoelastic state without loss of material coherence. Therefore, previously generated modifications can be preserved. To prove the feasibility of our newly developed technique, so called SMART = Substrate Modification And Replication by Thermoforming, polymer films treated by various polymer modification methods, like UV-based patterned films, and films modified by the bombardment with energetic heavy ions, were post-processed by microthermoforming. The preservation of locally applied specific surface and bulk features was demonstrated e.g. by the selective adhesion of cells to patterned microcavity walls.

  6. Hot deformation characterization of duplex low-density steel through 3D processing map development

    SciTech Connect

    Mohamadizadeh, A.; Zarei-Hanzaki, A.; Abedi, H.R.; Mehtonen, S.; Porter, D.

    2015-09-15

    The high temperature deformation behavior of duplex low-density Fe–18Mn–8Al–0.8C steel was investigated at temperatures in the range of 600–1000 °C. The primary constitutive analysis indicated that the Zener–Hollomon parameter, which represents the coupled effects of temperature and strain rate, significantly varies with the amount of deformation. Accordingly, the 3D processing maps were developed considering the effect of strain and were used to determine the safe and unsafe deformation conditions in association with the microstructural evolution. The deformation at efficiency domain I (900–1100 °C\\10{sup −} {sup 2}–10{sup −} {sup 3} s{sup −} {sup 1}) was found to be safe at different strains due to the occurrence of dynamic recrystallization in austenite. The safe efficiency domain II (700–900 °C\\1–10{sup −} {sup 1} s{sup −} {sup 1}), which appeared at logarithmic strain of 0.4, was characterized by deformation induced ferrite formation. Scanning electron microscopy revealed that the microband formation and crack initiation at ferrite\\austenite interphases were the main causes of deformation instability at 600–800 °C\\10{sup −} {sup 2}–10{sup −} {sup 3} s{sup −} {sup 1}. The degree of instability was found to decrease by increasing the strain due to the uniformity of microbanded structure obtained at higher strains. The shear band formation at 900–1100 °C\\1–10{sup −} {sup 1} s{sup −} {sup 1} was verified by electron backscattered diffraction. The local dynamic recrystallization of austenite and the deformation induced ferrite formation were observed within shear-banded regions as the results of flow localization. - Graphical abstract: Display Omitted - Highlights: • The 3D processing map is developed for duplex low-density Fe–Mn–Al–C steel. • The efficiency domains shrink, expand or appear with increasing strain. • The occurrence of DRX and DIFF increases the power efficiency. • Crack initiation

  7. Real-time Process Monitoring and Temperature Mapping of the 3D Polymer Printing Process

    SciTech Connect

    Dinwiddie, Ralph Barton; Love, Lonnie J; Rowe, John C

    2013-01-01

    An extended range IR camera was used to make temperature measurements of samples as they are being manufactured. The objective is to quantify the temperature variation inside the system as parts are being fabricated, as well as quantify the temperature of a part during fabrication. The IR camera was used to map the temperature within the build volume of the oven and surface temperature measurement of a part as it was being manufactured. The development of the temperature map of the oven provides insight into the global temperature variation within the oven that may lead to understanding variations in the properties of parts as a function of location. The observation of the temperature variation of a part that fails during construction provides insight into how the deposition process itself impacts temperature distribution within a single part leading to failure.

  8. Improving organic tandem solar cells based on water-processed nanoparticles by quantitative 3D nanoimaging.

    PubMed

    Pedersen, E B L; Angmo, D; Dam, H F; Thydén, K T S; Andersen, T R; Skjønsfjell, E T B; Krebs, F C; Holler, M; Diaz, A; Guizar-Sicairos, M; Breiby, D W; Andreasen, J W

    2015-08-28

    Organic solar cells have great potential for upscaling due to roll-to-roll processing and a low energy payback time, making them an attractive sustainable energy source for the future. Active layers coated with water-dispersible Landfester particles enable greater control of the layer formation and easier access to the printing industry, which has reduced the use of organic solvents since the 1980s. Through ptychographic X-ray computed tomography (PXCT), we image quantitatively a roll-to-roll coated photovoltaic tandem stack consisting of one bulk heterojunction active layer and one Landfester particle active layer. We extract the layered morphology with structural and density information including the porosity present in the various layers and the silver electrode with high resolution in 3D. The Landfester particle layer is found to have an undesired morphology with negatively correlated top- and bottom interfaces, wide thickness distribution and only partial surface coverage causing electric short circuits through the layer. By top coating a polymer material onto the Landfester nanoparticles we eliminate the structural defects of the layer such as porosity and roughness, and achieve the increased performance larger than 1 V expected for a tandem cell. This study highlights that quantitative imaging of weakly scattering stacked layers of organic materials has become feasible by PXCT, and that this information cannot be obtained by other methods. In the present study, this technique specifically reveals the need to improve the coatability and layer formation of Landfester nanoparticles, thus allowing improved solar cells to be produced.

  9. 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.

  10. 3-D hydrodynamic modelling of flood impacts on a building and indoor flooding processes

    NASA Astrophysics Data System (ADS)

    Gems, Bernhard; Mazzorana, Bruno; Hofer, Thomas; Sturm, Michael; Gabl, Roman; Aufleger, Markus

    2016-06-01

    Given the current challenges in flood risk management and vulnerability assessment of buildings exposed to flood hazards, this study presents three-dimensional numerical modelling of torrential floods and its interaction with buildings. By means of a case study application, the FLOW-3D software is applied to the lower reach of the Rio Vallarsa torrent in the village of Laives (Italy). A single-family house on the flood plain is therefore considered in detail. It is exposed to a 300-year flood hydrograph. Different building representation scenarios, including an entire impervious building envelope and the assumption of fully permeable doors, light shafts and windows, are analysed. The modelling results give insight into the flooding process of the building's interior, the impacting hydrodynamic forces on the exterior and interior walls, and further, they quantify the impact of the flooding of a building on the flow field on the surrounding flood plain. The presented study contributes to the development of a comprehensive physics-based vulnerability assessment framework. For pure water floods, this study presents the possibilities and limits of advanced numerical modelling techniques within flood risk management and, thereby, the planning of local structural protection measures.

  11. 3D printed glass: surface finish and bulk properties as a function of the printing process

    NASA Astrophysics Data System (ADS)

    Klein, Susanne; Avery, Michael P.; Richardson, Robert; Bartlett, Paul; Frei, Regina; Simske, Steven

    2015-03-01

    It is impossible to print glass directly from a melt, layer by layer. Glass is not only very sensitive to temperature gradients between different layers but also to the cooling process. To achieve a glass state the melt, has to be cooled rapidly to avoid crystallization of the material and then annealed to remove cooling induced stress. In 3D-printing of glass the objects are shaped at room temperature and then fired. The material properties of the final objects are crucially dependent on the frit size of the glass powder used during shaping, the chemical formula of the binder and the firing procedure. For frit sizes below 250 μm, we seem to find a constant volume of pores of less than 5%. Decreasing frit size leads to an increase in the number of pores which then leads to an increase of opacity. The two different binders, 2- hydroxyethyl cellulose and carboxymethylcellulose sodium salt, generate very different porosities. The porosity of samples with 2-hydroxyethyl cellulose is similar to frit-only samples, whereas carboxymethylcellulose sodium salt creates a glass foam. The surface finish is determined by the material the glass comes into contact with during firing.

  12. Multigrid direct numerical simulation of the whole process of flow transition in 3-D boundary layers

    NASA Technical Reports Server (NTRS)

    Liu, Chaoqun; Liu, Zhining

    1993-01-01

    A new technology was developed in this study which provides a successful numerical simulation of the whole process of flow transition in 3-D boundary layers, including linear growth, secondary instability, breakdown, and transition at relatively low CPU cost. Most other spatial numerical simulations require high CPU cost and blow up at the stage of flow breakdown. A fourth-order finite difference scheme on stretched and staggered grids, a fully implicit time marching technique, a semi-coarsening multigrid based on the so-called approximate line-box relaxation, and a buffer domain for the outflow boundary conditions were all used for high-order accuracy, good stability, and fast convergence. A new fine-coarse-fine grid mapping technique was developed to keep the code running after the laminar flow breaks down. The computational results are in good agreement with linear stability theory, secondary instability theory, and some experiments. The cost for a typical case with 162 x 34 x 34 grid is around 2 CRAY-YMP CPU hours for 10 T-S periods.

  13. Simulation of abrasive flow machining process for 2D and 3D mixture models

    NASA Astrophysics Data System (ADS)

    Dash, Rupalika; Maity, Kalipada

    2015-12-01

    Improvement of surface finish and material removal has been quite a challenge in a finishing operation such as abrasive flow machining (AFM). Factors that affect the surface finish and material removal are media viscosity, extrusion pressure, piston velocity, and particle size in abrasive flow machining process. Performing experiments for all the parameters and accurately obtaining an optimized parameter in a short time are difficult to accomplish because the operation requires a precise finish. Computational fluid dynamics (CFD) simulation was employed to accurately determine optimum parameters. In the current work, a 2D model was designed, and the flow analysis, force calculation, and material removal prediction were performed and compared with the available experimental data. Another 3D model for a swaging die finishing using AFM was simulated at different viscosities of the media to study the effects on the controlling parameters. A CFD simulation was performed by using commercially available ANSYS FLUENT. Two phases were considered for the flow analysis, and multiphase mixture model was taken into account. The fluid was considered to be a

  14. Performance evaluation of laser line scanner for in-process inspection of 3D geometries

    NASA Astrophysics Data System (ADS)

    Zhou, Sen; Xu, Jian; Tao, Lei; Yan, Yu

    2016-09-01

    Non-contact measurement techniques using laser scanning have the power to deliver tremendous benefits to most notably manufacturing, and have the advantage of high speed and high detail output. However, a major obstacle to their widespread adoption in more complex on-line producing environments is their geometric constraints and low accuracy compared to the contact-based counterparts. The work presented in this paper introduces a performance evaluation test of laser line scanning for in-process inspection of 3D geometries. Some straightforward test methods that use a designed artifact are proposed. First, one work aims to experimentally investigate the location accuracy of knee point or corner point of edge features using a commercial laser stripe scanner, which is common in mechanical parts. Another work experimentally investigates the formation of outliers that may be usually promoted by reflective surfaces around surrounding area of corner point, and these outliers are characterized with large measurement errors, which significantly deteriorate the quality of the scanned point cloud data. Scanning path planning and outlier filter design are respectively discussed.

  15. Synthesis and 3D printing of biodegradable polyurethane elastomer by a water-based process for cartilage tissue engineering applications.

    PubMed

    Hung, Kun-Che; Tseng, Ching-Shiow; Hsu, Shan-Hui

    2014-10-01

    Biodegradable materials that can undergo degradation in vivo are commonly employed to manufacture tissue engineering scaffolds, by techniques including the customized 3D printing. Traditional 3D printing methods involve the use of heat, toxic organic solvents, or toxic photoinitiators for fabrication of synthetic scaffolds. So far, there is no investigation on water-based 3D printing for synthetic materials. In this study, the water dispersion of elastic and biodegradable polyurethane (PU) nanoparticles is synthesized, which is further employed to fabricate scaffolds by 3D printing using polyethylene oxide (PEO) as a viscosity enhancer. The surface morphology, degradation rate, and mechanical properties of the water-based 3D-printed PU scaffolds are evaluated and compared with those of polylactic-co-glycolic acid (PLGA) scaffolds made from the solution in organic solvent. These scaffolds are seeded with chondrocytes for evaluation of their potential as cartilage scaffolds. Chondrocytes in 3D-printed PU scaffolds have excellent seeding efficiency, proliferation, and matrix production. Since PU is a category of versatile materials, the aqueous 3D printing process developed in this study is a platform technology that can be used to fabricate devices for biomedical applications. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Improving organic tandem solar cells based on water-processed nanoparticles by quantitative 3D nanoimaging

    NASA Astrophysics Data System (ADS)

    Pedersen, E. B. L.; Angmo, D.; Dam, H. F.; Thydén, K. T. S.; Andersen, T. R.; Skjønsfjell, E. T. B.; Krebs, F. C.; Holler, M.; Diaz, A.; Guizar-Sicairos, M.; Breiby, D. W.; Andreasen, J. W.

    2015-08-01

    Organic solar cells have great potential for upscaling due to roll-to-roll processing and a low energy payback time, making them an attractive sustainable energy source for the future. Active layers coated with water-dispersible Landfester particles enable greater control of the layer formation and easier access to the printing industry, which has reduced the use of organic solvents since the 1980s. Through ptychographic X-ray computed tomography (PXCT), we image quantitatively a roll-to-roll coated photovoltaic tandem stack consisting of one bulk heterojunction active layer and one Landfester particle active layer. We extract the layered morphology with structural and density information including the porosity present in the various layers and the silver electrode with high resolution in 3D. The Landfester particle layer is found to have an undesired morphology with negatively correlated top- and bottom interfaces, wide thickness distribution and only partial surface coverage causing electric short circuits through the layer. By top coating a polymer material onto the Landfester nanoparticles we eliminate the structural defects of the layer such as porosity and roughness, and achieve the increased performance larger than 1 V expected for a tandem cell. This study highlights that quantitative imaging of weakly scattering stacked layers of organic materials has become feasible by PXCT, and that this information cannot be obtained by other methods. In the present study, this technique specifically reveals the need to improve the coatability and layer formation of Landfester nanoparticles, thus allowing improved solar cells to be produced.Organic solar cells have great potential for upscaling due to roll-to-roll processing and a low energy payback time, making them an attractive sustainable energy source for the future. Active layers coated with water-dispersible Landfester particles enable greater control of the layer formation and easier access to the printing

  17. RT3D tutorials for GMS users

    SciTech Connect

    Clement, T.P.; Jones, N.L.

    1998-02-01

    RT3D (Reactive Transport in 3-Dimensions) is a computer code that solves coupled partial differential equations that describe reactive-flow and transport of multiple mobile and/or immobile species in a three dimensional saturated porous media. RT3D was developed from the single-species transport code, MT3D (DoD-1.5, 1997 version). As with MT3D, RT3D also uses the USGS groundwater flow model MODFLOW for computing spatial and temporal variations in groundwater head distribution. This report presents a set of tutorial problems that are designed to illustrate how RT3D simulations can be performed within the Department of Defense Groundwater Modeling System (GMS). GMS serves as a pre- and post-processing interface for RT3D. GMS can be used to define all the input files needed by RT3D code, and later the code can be launched from within GMS and run as a separate application. Once the RT3D simulation is completed, the solution can be imported to GMS for graphical post-processing. RT3D v1.0 supports several reaction packages that can be used for simulating different types of reactive contaminants. Each of the tutorials, described below, provides training on a different RT3D reaction package. Each reaction package has different input requirements, and the tutorials are designed to describe these differences. Furthermore, the tutorials illustrate the various options available in GMS for graphical post-processing of RT3D results. Users are strongly encouraged to complete the tutorials before attempting to use RT3D and GMS on a routine basis.

  18. Adaptive quality assurance of the product development process of additive manufacturing with modern 3D data evaluation methods

    NASA Astrophysics Data System (ADS)

    Kroll, Julia; Botta, Sabine; Breuninger, Jannis; Verl, Alexander

    2013-03-01

    In this paper, the possibilities of modern 3D data evaluation for metrology and quality assurance are presented for the special application of the plastic laser sinter process, especially the Additive Manufacturing process. We use the advantages of computer tomography and of the 3D focus variation at all stages of a production process for an increased quality of the resulting products. With the CT and the 3D focus variation the modern quality assurance and metrology have state of the art instruments that allow non-destructive, complete and accurate measuring of parts. Therefore, these metrological methods can be used in many stages of the product development process for non-destructive quality control. In this work, studies and evaluation of 3D data and the conclusions for relevant quality criteria are presented. Additionally, new developments and implementations for adapting the evaluation results for quality prediction, comparison and for correction are described to show how an adequate process control can be achieved with the help of modern 3D metrology techniques. The focus is on the optimization of laser sintering components with regard to their quality requirements so that the functionality during production can be guaranteed and quantified.

  19. 3D printed electromagnetic transmission and electronic structures fabricated on a single platform using advanced process integration techniques

    NASA Astrophysics Data System (ADS)

    Deffenbaugh, Paul Issac

    3D printing has garnered immense attention from many fields including in-office rapid prototyping of mechanical parts, outer-space satellite replication, garage functional firearm manufacture, and NASA rocket engine component fabrication. 3D printing allows increased design flexibility in the fabrication of electronics, microwave circuits and wireless antennas and has reached a level of maturity which allows functional parts to be printed. Much more work is necessary in order to perfect the processes of 3D printed electronics especially in the area of automation. Chapter 1 shows several finished prototypes of 3D printed electronics as well as newly developed techniques in fabrication. Little is known about the RF and microwave properties and applications of the standard materials which have been developed for 3D printing. Measurement of a wide variety of materials over a broad spectrum of frequencies up to 10 GHz using a variety of well-established measurement methods is performed throughout chapter 2. Several types of high frequency RF transmission lines are fabricated and valuable model-matched data is gathered and provided in chapter 3 for future designers' use. Of particular note is a fully 3D printed stripline which was automatically fabricated in one process on one machine. Some core advantages of 3D printing RF/microwave components include rapid manufacturing of complex, dimensionally sensitive circuits (such as antennas and filters which are often iteratively tuned) and the ability to create new devices that cannot be made using standard fabrication techniques. Chapter 4 describes an exemplary fully 3D printed curved inverted-F antenna.

  20. Effects of Processing and Medical Sterilization Techniques on 3D-Printed and Molded Polylactic Acid

    NASA Astrophysics Data System (ADS)

    Geritano, Mariah Nicole

    Manufacturing industries have evolved tremendously in the past decade with the introduction of Additive Manufacturing (AM), also known as 3D Printing. The medical device industry has been a leader in adapting this new technology into research and development. 3D printing enables medical devices and implants to become more customizable, patient specific, and allows for low production numbers. This study compares the mechanical and thermal properties of traditionally manufactured parts versus parts manufactured through 3D printing before and after sterilization, and the ability of an FDM printer to produce reliable, identical samples. It was found that molded samples and 100% infill high-resolution samples have almost identical changes in properties when exposed to different sterilization methods, and similar cooling rates. The data shown throughout this investigation confirms that manipulation of printing parameters can result in an object with comparable material properties to that created through traditional manufacturing methods.

  1. Variation in spectral and mass dimension on 3D soil image processing

    NASA Astrophysics Data System (ADS)

    Sanchez, M. E.; Tarquis, A. M.; Fabregat, J.; Andina, D.; Jimenez, J.; Crawford, J. W.

    2009-04-01

    Knowledge on three dimensional soil pore architecture is important for understanding soil processes as it controls biological, chemical and physical processes on various scales. Recent advances in non-destructive imaging, such as X-ray Computed Tomography (CT), provide several ways to analyze pore space features mainly concentrating on the visualization of soil structure. Fractal formalism has revealed as useful tool in these cases where highly complex and heterogeneous medium are studied. One of these quantifications is mass dimension (Dm) and spectral dimension (d) applied for water and gas diffusion coefficient in soil. At the same time that these techniques give a unique opportunity to quantify and describe pore space, they presents steps in their procedures on which the results depend. In this work, intact soil samples were collected from four horizons of a Brazilian soil and 3D images, of 45.1 micro-m resolution (256x256x256 voxels), were obtained. Four different threshold criteria were used to transform CT grey-scale imagery in binary imagery (pore/solid), based on the frequency of CT units. Then the threshold effect on the estimation of Dm and d, as well as their ratio was studied. Each threshold criteria had a direct influence on Dm as it has been previously reported [1], through the increase on porosity obtained. Meanwhile Dm showed a clear logarithmic relation with the apparent porosity in the image obtained for each threshold, d showed an almost linear one. In any case the increase of each one of them respect to porosity was different for each horizon. The Dm/d ratio was practically constant through all the porosity achieved in this study when Dm was estimated using all the scale range available. On the other hand, when Dm was estimated based on smaller scales this ratio depended on the threshold criteria applied to the image. This fact has a direct implication in diffusion parameters for a pore network modeling based on both fractal dimensions. [1] A

  2. Precipitation Processes Developed During ARM (1997), TOGA COARE (1992) GATE (1974), SCSMEX (1998), and KWAJEX (1999): Consistent 3D, Semi-3D and 3D Cloud Resolving Model Simulations

    NASA Technical Reports Server (NTRS)

    Tao, W.-K.; Hou, A.; Atlas, R.; Starr, D.; Sud, Y.

    2003-01-01

    Real clouds and cloud systems are inherently three-dimensional (3D). Because of the limitations in computer resources, however, most cloud-resolving models (CRMs) today are still two-dimensional (2D) have been used to study the response of clouds to large-scale forcing. IN these 3D simulators, the model domain was small, and the integration time was 6 hours. Only recently have 3D experiments been performed for multi-day periods for tropical clouds systems with large horizontal domains at the National Center of Atmospheric Research (NCAR) and at NASA Goddard Space Center. At Goddard, a 3D cumulus Ensemble (GCE) model was used to simulate periods during TOGA COARE, GATE, SCSMEX, ARM, and KWAJEX using a 512 by 512 km domain (with 2-km resolution). The result indicate that surface precipitation and latent heating profiles are very similar between the 2D and 3D GCE model simulation. The major objective of this paper are: (1) to assess the performance of the super-parametrization technique, (2) calculate and examine the surface energy (especially radiation) and water budget, and (3) identify the differences and similarities in the organization and entrainment rates of convection between simulated 2D and 3D cloud systems.

  3. Simulation-Based Evaluation of Light Posts and Street Signs as 3-D Geolocation Targets in SAR Images

    NASA Astrophysics Data System (ADS)

    Auer, S.; Balss, U.

    2017-05-01

    The assignment of phase center positions (in 2D or 3D) derived from SAR data to physical object is challenging for many man-made structures such as buildings or bridges. In contrast, light poles and traffic signs are promising targets for tasks based on 3-D geolocation as they often show a prominent and spatially isolated appearance. For a detailed understanding of the nature of both targets, this paper presents results of a dedicated simulation case study, which is based on ray tracing methods (simulator RaySAR). For the first time, the appearance of the targets is analyzed in 2D (image plane) and 3D space (world coordinates of scene model) and reflecting surfaces are identified for related dominant image pixels. The case studies confirms the crucial impact of spatial resolution in the context of light poles and traffic signs and the appropriateness of light poles as target for 3-D geolocation in case of horizontal ground surfaces beneath.

  4. New insights in catchment processes via distributed soil moisture measurements and 3D hydrological modeling

    NASA Astrophysics Data System (ADS)

    Bogena, H. R.; Sciuto, G.; Rosenbaum, U.; Herbst, M.; Huisman, J. A.; Vereecken, H.; Diekkrueger, B.

    2010-12-01

    Hydrological analysis is often limited by the number of data available. Usually, discharge data and only little point information concerning soil moisture status are available. This might give a good representation of the temporal variability of runoff, but it does not provide insights into the spatial dynamics of soil moisture and water fluxes within the catchment. The small forested Wüstebach catchment (~27 ha) has been instrumented with a wireless sensor network consisting of 150 nodes and more than 1200 soil moisture sensors in the framework of the Transregio32 and the Helmholtz initiative TERENO (Terrestrial Environmental Observatories) [1]. This unique data set provides a consistent picture of the hydrological status of the catchment in a high spatial and temporal resolution. We present first results of a geostatistical analysis of the data and an application of the integrated surface/subsurface 3D finite element model HydroGeoSphere model to investigate the scale dependency of the temporal dynamics of soil moisture patterns. A variogram analysis showed that the sum of the sub-scale variability and the measurement error is close to time-invariant. Wet situations showed smaller spatial variability, which is attributed to saturated soil moisture, which poses an upper limit and is typically not strongly variable in headwater catchments with relatively homogeneous soil. The spatiotemporal variability in soil moisture at 50 cm depth was significantly lower than at 5 and 20 cm. This finding indicates that the considerable variability of the top soil is buffered deeper in the soil due to root water uptake, lateral and vertical water fluxes. Topographic features showed the strongest correlation with soil moisture during dry periods, indicating that the control of topography on the soil moisture pattern depends on the soil water status. The temporal patterns of runoff discharge were reproduced by the HydroGeoSphere model in a satisfying way. The observed soil

  5. A Comprehensive 3D Mathematical Model of the Electroslag Remelting Process

    NASA Astrophysics Data System (ADS)

    Wang, Xiaohua; Li, Ying

    2015-08-01

    A comprehensive 3D mathematical model was proposed to predict the electromagnetic field, the multiphase flow field, the temperature field, and the pool profile of an industrial electroslag remelting (ESR) system. Especially, the metal droplets formation and falling in the slag pool during the ESR process are taken into account using the volume of fluid method. In addition, the electromagnetic and solidification phenomena are modeled using the magnetic vector potential method and the enthalpy-porosity method, respectively. The predicted results were found to be in good agreement with experimental measurements, regarding the magnetic flux density, the pool profile, the energy consumption, and the melt rate. And the model developed in the present work has been proved to be a powerful tool to provide a useful insight into the multi-physical phenomena in the ESR system. The results show that the Joule heating is mainly distributed in the slag pool due to the lower electrical conductivity of slag, and provides the thermal energy for melting the electrode. The molten metal on the conical electrode surface is washed away by the Lorentz force and the gravity force and gradually accumulates at the electrode tip. When the drop at the electrode tip reaches the critical size, the small droplets form due to the necking effect and depart from the conical electrode tip. In the slag pool, there are two axisymmetric vortexes with downward flows under the conical electrode tip, where the Lorentz force and the falling droplets are dominant, and another two axisymmetric vortexes with downward flows near the mold surface, where the thermal buoyancy is dominant. However, in the metal pool, there are only two vortexes with downward flows at the solidification front, where a high thermal gradient exists. The slag is significantly hotter and more uniform than the metal, because of an abundant of Joule heating and intensive turbulence in the slag pool. The molten metal is directionally

  6. 3D Printing Processes Applied to the Creation of Glass Art

    ERIC Educational Resources Information Center

    Chivers, Morgan

    2015-01-01

    The purpose of this article is to present a few of the innovative techniques used in the execution of Morgan Chivers' sculptural work, not on the content of the work itself. The author's interest has been in merging the methodologies and precise output control of 3D printing with finished objects in nonprintable materials as required by the…

  7. 3D-Printed Metal-Organic Framework Monoliths for Gas Adsorption Processes.

    PubMed

    Thakkar, Harshul; Eastman, Stephen; Al-Naddaf, Qasim; Rownaghi, Ali A; Rezaei, Fateme

    2017-10-03

    Metal-organic frameworks (MOFs) have shown promising performance in separation, adsorption, reaction, and storage of various industrial gases; however, their large-scale applications have been hampered by the lack of a proper strategy to formulate them into scalable gas-solid contactors. Herein, we report the fabrication of MOF monoliths using the 3D printing technique and evaluation of their adsorptive performance in CO2 removal from air. The 3D-printed MOF-74(Ni) and UTSA-16(Co) monoliths with MOF loadings as high as 80 and 85 wt %, respectively, were developed, and their physical and structural properties were characterized and compared with those of MOF powders. Our adsorption experiments showed that, upon exposure to 5000 ppm (0.5%) CO2 at 25 °C, the MOF-74(Ni) and UTSA-16(Co) monoliths can adsorb CO2 with uptake capacities of 1.35 and 1.31 mmol/g, respectively, which are 79% and 87% of the capacities of their MOF analogues under the same conditions. Furthermore, a stable performance was obtained for self-standing 3D-printed monolithic structures with relatively good adsorption kinetics. The preliminary findings reported in this investigation highlight the advantage of the robocasting (3D printing) technique for shaping MOF materials into practical configurations that are suitable for various gas separation applications.

  8. A 3-d laser scanning system and scan data processing method for the monitoring of tunnel deformations

    NASA Astrophysics Data System (ADS)

    Chmelina, Klaus; Jansa, Josef; Hesina, Gerd; Traxler, Christoph

    2012-11-01

    The paper presents the mobile multi-sensor system Orthos Plus for the monitoring and mapping of tunnel walls, a scan data processing method for the evaluation of 3-d tunnel wall displacements from subsequent wall scans and, finally, a virtual reality tool supporting the interpretation of data. The measuring system consists of a 3-d laser scanner, a motorised total station and a digital camera that are integrated on a light metal frame that is installed on a mobile platform. It has been designed to perform tunnel measurements most efficiently and to meet the special requirements of tunnels under construction. The evaluation of 3-d displacements is based on a 3-d matching algorithm that takes advantage of the particular conditions of tunnel (shotcrete) surfaces. The virtual reality tool allows viewing of data in a 3-d virtual reality tunnel model and their animation in time and space in order supports understanding in an optimal way. The measuring system Orthos Plus has been developed in the course of a national research project, the 3-d matching method in the frame of the Austrian Christian Doppler Laboratory Spatial Data from Laser Scanning and Remote Sensing and the VR tool in the Austrian COMET K1 Competence Center VRVis Center (www.vrvis.at).

  9. Segmentation process significantly influences the accuracy of 3D surface models derived from cone beam computed tomography.

    PubMed

    Fourie, Zacharias; Damstra, Janalt; Schepers, Rutger H; Gerrits, Peter O; Ren, Yijin

    2012-04-01

    To assess the accuracy of surface models derived from 3D cone beam computed tomography (CBCT) with two different segmentation protocols. Seven fresh-frozen cadaver heads were used. There was no conflict of interests in this study. CBCT scans were made of the heads and 3D surface models were created of the mandible using two different segmentation protocols. The one series of 3D models was segmented by a commercial software company, while the other series was done by an experienced 3D clinician. The heads were then macerated following a standard process. A high resolution laser surface scanner was used to make a 3D model of the macerated mandibles, which acted as the reference 3D model or "gold standard". The 3D models generated from the two rendering protocols were compared with the "gold standard" using a point-based rigid registration algorithm to superimpose the three 3D models. The linear difference at 25 anatomic and cephalometric landmarks between the laser surface scan and the 3D models generate from the two rendering protocols was measured repeatedly in two sessions with one week interval. The agreement between the repeated measurement was excellent (ICC=0.923-1.000). The mean deviation from the gold standard by the 3D models generated from the CS group was 0.330mm±0.427, while the mean deviation from the Clinician's rendering was 0.763mm±0.392. The surface models segmented by both CS and DS protocols tend to be larger than those of the reference models. In the DS group, the biggest mean differences with the LSS models were found at the points ConLatR (CI: 0.83-1.23), ConMedR (CI: -3.16 to 2.25), CoLatL (CI: -0.68 to 2.23), Spine (CI: 1.19-2.28), ConAntL (CI: 0.84-1.69), ConSupR (CI: -1.12 to 1.47) and RetMolR (CI: 0.84-1.80). The Commercially segmented models resembled the reality more closely than the Doctor's segmented models. If 3D models are needed for surgical drilling guides or surgical planning which requires high precision, the additional cost of

  10. Laser scanner data processing and 3D modeling using a free and open source software

    SciTech Connect

    Gabriele, Fatuzzo; Michele, Mangiameli Giuseppe, Mussumeci; Salvatore, Zito

    2015-03-10

    The laser scanning is a technology that allows in a short time to run the relief geometric objects with a high level of detail and completeness, based on the signal emitted by the laser and the corresponding return signal. When the incident laser radiation hits the object to detect, then the radiation is reflected. The purpose is to build a three-dimensional digital model that allows to reconstruct the reality of the object and to conduct studies regarding the design, restoration and/or conservation. When the laser scanner is equipped with a digital camera, the result of the measurement process is a set of points in XYZ coordinates showing a high density and accuracy with radiometric and RGB tones. In this case, the set of measured points is called “point cloud” and allows the reconstruction of the Digital Surface Model. Even the post-processing is usually performed by closed source software, which is characterized by Copyright restricting the free use, free and open source software can increase the performance by far. Indeed, this latter can be freely used providing the possibility to display and even custom the source code. The experience started at the Faculty of Engineering in Catania is aimed at finding a valuable free and open source tool, MeshLab (Italian Software for data processing), to be compared with a reference closed source software for data processing, i.e. RapidForm. In this work, we compare the results obtained with MeshLab and Rapidform through the planning of the survey and the acquisition of the point cloud of a morphologically complex statue.

  11. Post-processing of data

    NASA Astrophysics Data System (ADS)

    Pfeifer, Hans-Joachim

    The post processing of Laser Doppler Anemometer (LDA) data has comparable influence on the final results, e.g. reliability, accuracy etc., as well as all the other aspects of LDA instruments. This is due to the fact that signal statistics in LDA are completely different from signal statistics well known in other measuring procedures where the continuous time history of the physical quantity under consideration is available. Four topics are presented: statistical quantities such as mean velocity, turbulence intensity, and histograms; filter control for both counter processors and FFT processors; auto and cross correlation and their Fourier transform; post processing of photon correlograms.

  12. 3D goes digital: from stereoscopy to modern 3D imaging techniques

    NASA Astrophysics Data System (ADS)

    Kerwien, N.

    2014-11-01

    In the 19th century, English physicist Charles Wheatstone discovered stereopsis, the basis for 3D perception. His construction of the first stereoscope established the foundation for stereoscopic 3D imaging. Since then, many optical instruments were influenced by these basic ideas. In recent decades, the advent of digital technologies revolutionized 3D imaging. Powerful readily available sensors and displays combined with efficient pre- or post-processing enable new methods for 3D imaging and applications. This paper draws an arc from basic concepts of 3D imaging to modern digital implementations, highlighting instructive examples from its 175 years of history.

  13. Parallel ALLSPD-3D: Speeding Up Combustor Analysis Via Parallel Processing

    NASA Technical Reports Server (NTRS)

    Fricker, David M.

    1997-01-01

    The ALLSPD-3D Computational Fluid Dynamics code for reacting flow simulation was run on a set of benchmark test cases to determine its parallel efficiency. These test cases included non-reacting and reacting flow simulations with varying numbers of processors. Also, the tests explored the effects of scaling the simulation with the number of processors in addition to distributing a constant size problem over an increasing number of processors. The test cases were run on a cluster of IBM RS/6000 Model 590 workstations with ethernet and ATM networking plus a shared memory SGI Power Challenge L workstation. The results indicate that the network capabilities significantly influence the parallel efficiency, i.e., a shared memory machine is fastest and ATM networking provides acceptable performance. The limitations of ethernet greatly hamper the rapid calculation of flows using ALLSPD-3D.

  14. Large 3D resistivity and induced polarization acquisition using the Fullwaver system: towards an adapted processing methodology

    NASA Astrophysics Data System (ADS)

    Leite, Orlando; Gance, Julien; Texier, Benoît; Bernard, Jean; Truffert, Catherine

    2017-04-01

    Driven by needs in the mineral exploration market for ever faster and ever easier set-up of large 3D resistivity and induced polarization, autonomous and cableless recorded systems come to the forefront. Opposite to the traditional centralized acquisition, this new system permits a complete random distribution of receivers on the survey area allowing to obtain a real 3D imaging. This work presents the results of a 3 km2 large experiment up to 600m of depth performed with a new type of autonomous distributed receivers: the I&V-Fullwaver. With such system, all usual drawbacks induced by long cable set up over large 3D areas - time consuming, lack of accessibility, heavy weight, electromagnetic induction, etc. - disappear. The V-Fullwavers record the entire time series of voltage on two perpendicular axes, for a good determination of the data quality although I-Fullwaver records injected current simultaneously. For this survey, despite good assessment of each individual signal quality, on each channel of the set of Fullwaver systems, a significant number of negative apparent resistivity and chargeability remains present in the dataset (around 15%). These values are commonly not taken into account in the inversion software although they may be due to complex geological structure of interest (e.g. linked to the presence of sulfides in the earth). Taking into account that such distributed recording system aims to restitute the best 3D resistivity and IP tomography, how can 3D inversion be improved? In this work, we present the dataset, the processing chain and quality control of a large 3D survey. We show that the quality of the data selected is good enough to include it into the inversion processing. We propose a second way of processing based on the modulus of the apparent resistivity that stabilizes the inversion. We then discuss the results of both processing. We conclude that an effort could be made on the inclusion of negative apparent resistivity in the inversion

  15. Joint 2D and 3D phase processing for quantitative susceptibility mapping: application to 2D echo-planar imaging.

    PubMed

    Wei, Hongjiang; Zhang, Yuyao; Gibbs, Eric; Chen, Nan-Kuei; Wang, Nian; Liu, Chunlei

    2017-04-01

    Quantitative susceptibility mapping (QSM) measures tissue magnetic susceptibility and typically relies on time-consuming three-dimensional (3D) gradient-echo (GRE) MRI. Recent studies have shown that two-dimensional (2D) multi-slice gradient-echo echo-planar imaging (GRE-EPI), which is commonly used in functional MRI (fMRI) and other dynamic imaging techniques, can also be used to produce data suitable for QSM with much shorter scan times. However, the production of high-quality QSM maps is difficult because data obtained by 2D multi-slice scans often have phase inconsistencies across adjacent slices and strong susceptibility field gradients near air-tissue interfaces. To address these challenges in 2D EPI-based QSM studies, we present a new data processing procedure that integrates 2D and 3D phase processing. First, 2D Laplacian-based phase unwrapping and 2D background phase removal are performed to reduce phase inconsistencies between slices and remove in-plane harmonic components of the background phase. This is followed by 3D background phase removal for the through-plane harmonic components. The proposed phase processing was evaluated with 2D EPI data obtained from healthy volunteers, and compared against conventional 3D phase processing using the same 2D EPI datasets. Our QSM results were also compared with QSM values from time-consuming 3D GRE data, which were taken as ground truth. The experimental results show that this new 2D EPI-based QSM technique can produce quantitative susceptibility measures that are comparable with those of 3D GRE-based QSM across different brain regions (e.g. subcortical iron-rich gray matter, cortical gray and white matter). This new 2D EPI QSM reconstruction method is implemented within STI Suite, which is a comprehensive shareware for susceptibility imaging and quantification. Copyright © 2016 John Wiley & Sons, Ltd.

  16. Can CH-53K 3D Technical Data Support the Provisioning Process

    DTIC Science & Technology

    2017-05-01

    CAD software format (CATIA, CREO, NX, SolidWorks , AutoCAD, etc.). Their inability to use the CH-53K CATIA models will preclude NAVSUP and DLA LIS...dimensional (3D) technical data formats are useful for weapon system design but do not support all downstream uses of that technical data. The Naval...CAD soft- ware formats . Addressing this challenge is extremely important for NAVSUP and DLA because many other new Navy programs are taking a

  17. High-Performance 3D Image Processing Architectures for Image-Guided Interventions

    DTIC Science & Technology

    2008-01-01

    D. J. Hawkes, "Voxel-based 2-D/3-D registration of fluoroscopy images and CT scans for image-guided surgery ," IEEE Transactions on Information...guided minimally invasive surgery ," Surgical Innovation, (in preparation), 2008. • O. Dandekar, W. Plishker, S. S. Bhattacharyya, and R. Shekhar... surgeries , biopsies, and therapies, have the potential to improve patient care by enabling new and faster procedures, minimizing unintended damage

  18. A 3D Polar Processing Algorithm for Scale Model UHF ISAR Imaging

    DTIC Science & Technology

    2006-05-01

    5 in order to allow visualization of the target’s main scattering features. The low level intensity in the imagery is represented by the color green ...imagery, one may observe higher level colors behind the low level green surfaces. Considering the relatively long wavelengths used in the 3D UHF ISAR...Lundberg, P. Follo, P. Frolind, and A. Gustavsson , “Performance of VHF-band SAR change detection for wide-area surveillance of concealed ground

  19. Understanding the mixing process in 3D microfluidic nozzle/diffuser systems: simulations and experiments

    NASA Astrophysics Data System (ADS)

    Sayah, Abdeljalil; Gijs, Martin A. M.

    2016-11-01

    We characterise computationally and experimentally a three-dimensional (3D) microfluidic passive mixer for various Reynolds numbers ranging from 1 to 100, corresponding to primary flow rates of 10-870 µl min-1. The 3D mixing channel is composed of multiple curved segments: circular arcs situated in the substrate plane and curved nozzle/diffuser elements normal to the substrate plane. Numerical simulation provides a detailed understanding of the mixing mechanism resulting from the geometrical topology of the mixer. These Comsol software-based simulations reveal the development of two secondary flows perpendicular to the primary flow: a swirling flow resulting from tangential injection of the flow into the nozzle holes and Dean vortices present in the circular arcs. These phenomena are particularly important at a Reynolds number larger than 30, where mixing occurs by chaotic advection. Experimentally, the 3D mixer is fabricated in a monolithic glass substrate by powder blasting machining, exploiting eroding powder beams at various angles of impact with respect to the substrate plane. Experimental mixing was characterised using two coloured dyes, showing nearly perfect mixing for a microfluidic footprint of the order of a few mm2, in good agreement with the simulations.

  20. 3-D imaging in post-traumatic malformation and eruptive disturbance in permanent incisors: a case report.

    PubMed

    Sahai, Sharad; Kaveriappa, Sushma; Arora, Honey; Aggarwal, Bharat

    2011-12-01

    Injury to the primary dentition is one of the common problems of childhood. Disturbances during crown development of the permanent teeth result in morphologic alterations. This case report highlights the role of 3-D imaging when conventional dental radiographs are not enough to answer our clinical questions regarding future eruptive disturbances. 3-D imaging can many times give us a definitive diagnosis and improve the treatment planning after early injuries in the deciduous dentition. The current status of multislice computed tomography (CT) and cone beam CT (CBCT) as diagnostic tools in pediatric dental population is also discussed briefly.

  1. 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…

  2. 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…

  3. 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…

  4. 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…

  5. The influence of the segmentation process on 3D measurements from cone beam computed tomography-derived surface models.

    PubMed

    Engelbrecht, Willem P; Fourie, Zacharias; Damstra, Janalt; Gerrits, Peter O; Ren, Yijin

    2013-11-01

    To compare the accuracy of linear and angular measurements between cephalometric and anatomic landmarks on surface models derived from 3D cone beam computed tomography (CBCT) with two different segmentation protocols was the aim of this study. CBCT scans were made of cadaver heads and 3D surface models were created of the mandible using two different segmentation protocols. A high-resolution laser surface scanner was used to make a 3D model of the macerated mandibles. Twenty linear measurements at 15 anatomic and cephalometric landmarks between the laser surface scan and the 3D models generated from the two segmentation protocols (commercial segmentation (CS) and doctor's segmentation (DS) groups) were measured. The interobserver agreement for all the measurements of the all three techniques was excellent (intraclass correlation coefficient 0.97-1.00). The results are for both groups very accurate, but only for the measurements on the condyle and lingual part of the mandible, the measurements in the CS group is slightly more accurate than the DS group. 3D surface models produced by CBCT are very accurate but slightly inferior to reality when threshold-based methods are used. Differences in the segmentation process resulted in significant clinical differences between the measurements. Care has to be taken when drawing conclusions from measurements and comparisons made from different segmentations, especially at the condylar region and the lingual side of the mandible.

  6. Precipitation processes developed during TOGA COARE (1992), GATE (1974), SCSMEX (1998), and KWAJEX (1999): 3D Cloud Resolving Model Simulation

    NASA Technical Reports Server (NTRS)

    Tao, W.-K.

    2006-01-01

    Real clouds and cloud systems are inherently three-dimensional (3D). Because of the limitations in computer resources, however, most cloud-resolving models (CRMs) today are still two-dimensional (2D). A few 3D CRMs have been used to study the response of clouds to large-scale forcing. In these 3D simulations, the model domain was small, and the integration time was 6 hours. Only recently have 3D experiments been performed for multi-day periods for tropical cloud systems with large horizontal domains at the National Center for Atmospheric Research (NCAR), NOAA GFDL, the U.K. Met. Office, Colorado State University and NASA Goddard Space Flight Center. An improved 3D Goddard Cumulus Ensemble (GCE) model was recently used to simulate periods during TOGA COARE (December 19-27, 1992), GATE (september 1-7, 1974), SCSMEX (May 18-26, June 2-11, 1998) and KWAJEX (August 7-13, August 18-21, and August 29-September 12, 1999) using a 512 by 512 km domain and 41 vertical layers. The major objectives of this paper are: (1) to identify the differences and similarities in the simulated precipitation processes and their associated surface and water energy budgets in TOGA COARE, GATE, KWAJEX, and SCSMEX, and (2) to asses the impact of microphysics, radiation budget and surface fluxes on the organization of convection in tropics.

  7. A unified 3D default space consciousness model combining neurological and physiological processes that underlie conscious experience.

    PubMed

    Jerath, Ravinder; Crawford, Molly W; Barnes, Vernon A

    2015-01-01

    The Global Workspace Theory and Information Integration Theory are two of the most currently accepted consciousness models; however, these models do not address many aspects of conscious experience. We compare these models to our previously proposed consciousness model in which the thalamus fills-in processed sensory information from corticothalamic feedback loops within a proposed 3D default space, resulting in the recreation of the internal and external worlds within the mind. This 3D default space is composed of all cells of the body, which communicate via gap junctions and electrical potentials to create this unified space. We use 3D illustrations to explain how both visual and non-visual sensory information may be filled-in within this dynamic space, creating a unified seamless conscious experience. This neural sensory memory space is likely generated by baseline neural oscillatory activity from the default mode network, other salient networks, brainstem, and reticular activating system.

  8. A unified 3D default space consciousness model combining neurological and physiological processes that underlie conscious experience

    PubMed Central

    Jerath, Ravinder; Crawford, Molly W.; Barnes, Vernon A.

    2015-01-01

    The Global Workspace Theory and Information Integration Theory are two of the most currently accepted consciousness models; however, these models do not address many aspects of conscious experience. We compare these models to our previously proposed consciousness model in which the thalamus fills-in processed sensory information from corticothalamic feedback loops within a proposed 3D default space, resulting in the recreation of the internal and external worlds within the mind. This 3D default space is composed of all cells of the body, which communicate via gap junctions and electrical potentials to create this unified space. We use 3D illustrations to explain how both visual and non-visual sensory information may be filled-in within this dynamic space, creating a unified seamless conscious experience. This neural sensory memory space is likely generated by baseline neural oscillatory activity from the default mode network, other salient networks, brainstem, and reticular activating system. PMID:26379573

  9. A facile one-step process for 3D N-doped noncovalent functionalization PS/rGO composites

    NASA Astrophysics Data System (ADS)

    Huang, Weiqi; Wang, Hua; Su, Zheng; Tian, Konghu; Ye, Xianzhu; Bao, Chao; Guo, Yulan; He, Jing; Tian, Xingyou

    2017-03-01

    This work reports a simple, versatile and facile one-step process to prepare the three-dimensional (3D) N-doped noncovalent functionalization polystyrene/reduced graphene oxide (PS/rGO) composites. In this, N, N-dimethylformamide (DMF) acts as the solvent, reducing agent, and more importantly, the N-doping agent. Various measurements have been carried out to characterize the structure and morphology of PS/rGO composites, in particular for the excellent electrical conductivity of PS/rGO composites compared with virgin PS, which was attributed to the 3D pores structure and the N-doping. With regards to the unique properties of graphene, the 3D framework structure and the N-doping, this composite material has great potential properties such as electro-magnetic interference shielding effectiveness (EMI) to be explored.

  10. Graphene Oxide: An All-in-One Processing Additive for 3D Printing.

    PubMed

    García-Tuñón, Esther; Feilden, Ezra; Zheng, Han; D'Elia, Eleonora; Leong, Alan; Saiz, Eduardo

    2017-09-27

    Many 3D printing technologies are based on the development of inks and pastes to build objects through droplet or filament deposition (the latter also known as continuous extrusion, robocasting, or direct ink writing). Controlling and tuning rheological behavior is key for successful manufacturing using these techniques. Different formulations have been proposed, but the search continues for approaches that are clean, flexible, robust and that can be adapted to a wide range of materials. Here, we show how graphene oxide (GO) enables the formulation of water-based pastes to print a wide variety of materials (polymers, ceramics, and steel) using robocasting. This work combines flow and oscillatory rheology to provide further insights into the rheological behavior of suspensions combining GO with other materials. Graphene oxide can be used to manipulate the viscoelastic response, enabling the formulation of pastes with excellent printing behavior that combine shear thinning flow and a fast recovery of their elastic properties. These inks do not contain other additives, only GO and the material of interest. As a proof of concept, we demonstrate the 3D printing of additive-free graphene oxide structures as well as polymers, ceramics, and steel. Due to its amphiphilic nature and 2D structure, graphene oxide plays multiple roles, behaving as a dispersant, viscosifier, and binder. It stabilizes suspensions of different powders, modifies the flow and viscoelasticity of materials with different chemistries, particle sizes and shapes, and binds the particles together, providing green strength for manual handling. This approach enables printing complex 3D ceramic structures using robocasting with similar properties to alternative formulations, thus demonstrating the potential of using 2D colloids in materials manufacturing.

  11. EEG-based cognitive load of processing events in 3D virtual worlds is lower than processing events in 2D displays.

    PubMed

    Dan, Alex; Reiner, Miriam

    2016-08-31

    Interacting with 2D displays, such as computer screens, smartphones, and TV, is currently a part of our daily routine; however, our visual system is built for processing 3D worlds. We examined the cognitive load associated with a simple and a complex task of learning paper-folding (origami) by observing 2D or stereoscopic 3D displays. While connected to an electroencephalogram (EEG) system, participants watched a 2D video of an instructor demonstrating the paper-folding tasks, followed by a stereoscopic 3D projection of the same instructor (a digital avatar) illustrating identical tasks. We recorded the power of alpha and theta oscillations and calculated the cognitive load index (CLI) as the ratio of the average power of frontal theta (Fz.) and parietal alpha (Pz). The results showed a significantly higher cognitive load index associated with processing the 2D projection as compared to the 3D projection; additionally, changes in the average theta Fz power were larger for the 2D conditions as compared to the 3D conditions, while alpha average Pz power values were similar for 2D and 3D conditions for the less complex task and higher in the 3D state for the more complex task. The cognitive load index was lower for the easier task and higher for the more complex task in 2D and 3D. In addition, participants with lower spatial abilities benefited more from the 3D compared to the 2D display. These findings have implications for understanding cognitive processing associated with 2D and 3D worlds and for employing stereoscopic 3D technology over 2D displays in designing emerging virtual and augmented reality applications.

  12. The valuable use of Microsoft Kinect™ sensor 3D kinematic in the rehabilitation process in basketball

    NASA Astrophysics Data System (ADS)

    Braidot, Ariel; Favaretto, Guillermo; Frisoli, Melisa; Gemignani, Diego; Gumpel, Gustavo; Massuh, Roberto; Rayan, Josefina; Turin, Matías

    2016-04-01

    Subjects who practice sports either as professionals or amateurs, have a high incidence of knee injuries. There are a few publications that show studies from a kinematic point of view of lateral-structure-knee injuries, including meniscal (meniscal tears or chondral injury), without anterior cruciate ligament rupture. The use of standard motion capture systems for measuring outdoors sport is hard to implement due to many operative reasons. Recently released, the Microsoft Kinect™ is a sensor that was developed to track movements for gaming purposes and has seen an increased use in clinical applications. The fact that this device is a simple and portable tool allows the acquisition of data of sport common movements in the field. The development and testing of a set of protocols for 3D kinematic measurement using the Microsoft Kinect™ system is presented in this paper. The 3D kinematic evaluation algorithms were developed from information available and with the use of Microsoft’s Software Development Kit 1.8 (SDK). Along with this, an algorithm for calculating the lower limb joints angles was implemented. Thirty healthy adult volunteers were measured, using five different recording protocols for sport characteristic gestures which involve high knee injury risk in athletes.

  13. RUBE: an XML-based architecture for 3D process modeling and model fusion

    NASA Astrophysics Data System (ADS)

    Fishwick, Paul A.

    2002-07-01

    Information fusion is a critical problem for science and engineering. There is a need to fuse information content specified as either data or model. We frame our work in terms of fusing dynamic and geometric models, to create an immersive environment where these models can be juxtaposed in 3D, within the same interface. The method by which this is accomplished fits well into other eXtensible Markup Language (XML) approaches to fusion in general. The task of modeling lies at the heart of the human-computer interface, joining the human to the system under study through a variety of sensory modalities. I overview modeling as a key concern for the Defense Department and the Air Force, and then follow with a discussion of past, current, and future work. Past work began with a package with C and has progressed, in current work, to an implementation in XML. Our current work is defined within the RUBE architecture, which is detailed in subsequent papers devoted to key components. We have built RUBE as a next generation modeling framework using our prior software, with research opportunities in immersive 3D and tangible user interfaces.

  14. The application of 3D image processing to studies of the musculoskeletal system

    NASA Astrophysics Data System (ADS)

    Hirsch, Bruce Elliot; Udupa, Jayaram K.; Siegler, Sorin; Winkelstein, Beth A.

    2009-10-01

    Three dimensional renditions of anatomical structures are commonly used to improve visualization, surgical planning, and patient education. However, such 3D images also contain information which is not readily apparent, and which can be mined to elucidate, for example, such parameters as joint kinematics, spacial relationships, and distortions of those relationships with movement. Here we describe two series of experiments which demonstrate the functional application of 3D imaging. The first concerns the joints of the ankle complex, where the usual description of motions in the talocrural joint is shown to be incomplete, and where the roles of the anterior talofibular and calcaneofibular ligaments are clarified in ankle sprains. Also, the biomechanical effects of two common surgical procedures for repairing torn ligaments were examined. The second series of experiments explores changes in the anatomical relationships between nerve elements and the cervical vertebrae with changes in neck position. They provide preliminary evidence that morphological differences may exist between asymptomatic subjects and patients with radiculopathy in certain positions, even when conventional imaging shows no difference.

  15. 3D FEA of cemented glass fiber and cast posts with various dental cements in a maxillary central incisor.

    PubMed

    Madfa, Ahmed A; Al-Hamzi, Mohsen A; Al-Sanabani, Fadhel A; Al-Qudaimi, Nasr H; Yue, Xiao-Guang

    2015-01-01

    This study aimed to analyse and compare the stability of two dental posts cemented with four different luting agents by examining their shear stress transfer through the FEM. Eight three-dimensional finite element models of a maxillary central incisor restored with glass fiber and Ni-Cr alloy cast dental posts. Each dental post was luted with zinc phosphate, Panavia resin, super bond C&B resin and glass ionomer materials. Finite element models were constructed and oblique loading of 100 N was applied. The distribution of shear stress was investigated at posts and cement/dentine interfaces using ABAQUS/CAE software. The peak shear stress for glass fiber post models minimized approximately three to four times of those for Ni-Cr alloy cast post models. There was negligible difference in peak of shear stress when various cements were compared, irrespective of post materials. The shear stress had same trend for all cement materials. This study found that the glass fiber dental post reduced the shear stress concentration at interfacial of post and cement/dentine compared to Ni-Cr alloy cast dental post.

  16. Effect of microgravity simulation using 3D clinostat on cavendish banana (Musa acuminata AAA Group) ripening process

    NASA Astrophysics Data System (ADS)

    Dwivany, Fenny Martha; Esyanti, Rizkita R.; Prapaisie, Adeline; Puspa Kirana, Listya; Latief, Chunaeni; Ginaldi, Ari

    2016-11-01

    The objective of the research was to determine the effect of microgravity simulation by 3D clinostat on Cavendish banana (Musa acuminata AAA group) ripening process. In this study, physical, physiological changes as well as genes expression were analysed. The result showed that in microgravity simulation condition ripening process in banana was delayed and the MaACOl, MaACSl and MaACS5 gene expression were affected.

  17. 3D surface roughness recreation and data processing of granitic rocks and claystones, potential host rocks for radioactive waste disposal

    NASA Astrophysics Data System (ADS)

    Buocz, Ildikó; Török, Ákos; Rozgonyi-Boissinot, Nikoletta

    2015-04-01

    The determination and modelling of the stability of rock slopes, tunnels, or underground spaces, i.e. radioactive waste disposal facilities, is an important task in engineering. The appropriate estimation of the mechanical parameters for a realistic description of the behaviour of rocks results in higher safety and more economic design. The failure of stability is primarily due to the shear failure of the rock masses along fractures and joints: therefore the correct determination of the shear strength is crucial. One of the most important parameters influencing the shear strength along rock joints is their surface roughness. Although the quantification of surface roughness has been an open question during the past century, several attempts have been made, starting with 2D and continuing with 3D measurements, to provide engineers with a method for determining shear strength numerically. As technology evolved, the 3D methods became more popular and several scientists started to investigate the surface properties through laser scanning and different photogrammetrical methods. This paper shows a photogrammetric method for the 3D digital recreation of joint surfaces of granitic rock and claystone, both potential host rocks for radioactive waste disposal. The rocks derived from Bátaapáti (South Hungary) and Mont Terri (North Switzerland) respectively. The samples are laboratory scaled specimens with an areal size of 50x50 mm. The software used is called ShapeMetrix3D, developed by 3GSM GmbH in Austria. The major steps of the creation of the 3D picture are presented, as well as the following data processing which leads to the quantification of the 3D surface roughness.

  18. 3D active edge silicon sensors: Device processing, yield and QA for the ATLAS-IBL production

    SciTech Connect

    Da Vià, Cinzia; Boscardil, Maurizio; Dalla Betta, GianFranco; Darbo, Giovanni; Fleta, Celeste; Gemme, Claudia; Giacomini, Gabriele; Grenier, Philippe; Grinstein, Sebastian; Hansen, Thor-Erik; Hasi, Jasmine; Kenney, Christopher; Kok, Angela; La Rosa, Alessandro; Micelli, Andrea; Parker, Sherwood; Pellegrini, Giulio; Pohl, David-Leon; Povoli, Marco; Vianello, Elisa; Zorzi, Nicola; Watts, S. J.

    2013-01-01

    3D silicon sensors, where plasma micromachining is used to etch deep narrow apertures in the silicon substrate to form electrodes of PIN junctions, were successfully manufactured in facilities in Europe and USA. In 2011 the technology underwent a qualification process to establish its maturity for a medium scale production for the construction of a pixel layer for vertex detection, the Insertable B-Layer (IBL) at the CERN-LHC ATLAS experiment. The IBL collaboration, following that recommendation from the review panel, decided to complete the production of planar and 3D sensors and endorsed the proposal to build enough modules for a mixed IBL sensor scenario where 25% of 3D modules populate the forward and backward part of each stave. The production of planar sensors will also allow coverage of 100% of the IBL, in case that option was required. This paper will describe the processing strategy which allowed successful 3D sensor production, some of the Quality Assurance (QA) tests performed during the pre-production phase and the production yield to date.

  19. Estimation of single cell volume from 3D confocal images using automatic data processing

    NASA Astrophysics Data System (ADS)

    Chorvatova, A.; Cagalinec, M.; Mateasik, A.; Chorvat, D., Jr.

    2012-06-01

    Cardiac cells are highly structured with a non-uniform morphology. Although precise estimation of their volume is essential for correct evaluation of hypertrophic changes of the heart, simple and unified techniques that allow determination of the single cardiomyocyte volume with sufficient precision are still limited. Here, we describe a novel approach to assess the cell volume from confocal microscopy 3D images of living cardiac myocytes. We propose a fast procedure based on segementation using active deformable contours. This technique is independent on laser gain and/or pinhole settings and it is also applicable on images of cells stained with low fluorescence markers. Presented approach is a promising new tool to investigate changes in the cell volume during normal, as well as pathological growth, as we demonstrate in the case of cell enlargement during hypertension in rats.

  20. Shape 4.0: 3D Shape Modeling and Processing Using Semantics.

    PubMed

    Spagnuolo, Michela

    2016-01-01

    In the last decade, sensor, communication, and computing technologies have advanced rapidly, producing dramatic changes in our daily lives and in a variety of application domains. Emerging technologies are leading us to a gradual, but inescapable integration of our material and digital realities and the advent of cyber-physical worlds. Although attaining visual realism is within the grasp of current 3D modeling approaches, it is less clear whether current modeling techniques will accommodate the needs of human communication and of the applications that we can already envisage in those futuristic worlds. Inspired by the evolution trends of the Web, this article describes the evolution of shape modeling from the Shape 1.0 geometry-only, mesh-based stage to the forthcoming semantics-driven Shape 4.0 era.

  1. Precision depth measurement of through silicon vias (TSVs) on 3D semiconductor packaging process.

    PubMed

    Jin, Jonghan; Kim, Jae Wan; Kang, Chu-Shik; Kim, Jong-Ahn; Lee, Sunghun

    2012-02-27

    We have proposed and demonstrated a novel method to measure depths of through silicon vias (TSVs) at high speed. TSVs are fine and deep holes fabricated in silicon wafers for 3D semiconductors; they are used for electrical connections between vertically stacked wafers. Because the high-aspect ratio hole of the TSV makes it difficult for light to reach the bottom surface, conventional optical methods using visible lights cannot determine the depth value. By adopting an optical comb of a femtosecond pulse laser in the infra-red range as a light source, the depths of TSVs having aspect ratio of about 7 were measured. This measurement was done at high speed based on spectral resolved interferometry. The proposed method is expected to be an alternative method for depth inspection of TSVs.

  2. Fully 3D Multiple Beam Dynamics Processes Simulation for the Fermilab Tevatron

    SciTech Connect

    Stern, E.; Amundson, J.; Spentzouris, P; Valishev, A.; /Fermilab

    2010-06-01

    The Fermilab Tevatron has been, until 2010, the premier high-energy physics collider in the world. The data collected over the last decade by high-energy physics experiments running at the Tevatron have been analyzed to make important measurements in fundamental areas such as B meson masses and flavor oscillation, searches for the Higgs boson, and supersymmetry. Collecting these data at the limits of detectability has required the Tevatron to operate reliably at high beam intensities to maximize the number of collisions to analyze. This impressive achievement has been assisted by the use of HPC resources and software provided through the SciDAC program. This paper describes the enhancements to the BeamBeam3d code to realistically simulate the Tevatron, the validation of these simulations, and the improvement in equipment reliability and personal safety achieved with the aid of simulations.

  3. Development and Evaluation of Roadside/Obstacle Detection Method Using 3D Scanned Data Processing

    NASA Astrophysics Data System (ADS)

    Yamamoto, Hiroshi; Ishii, Yoshinori; Yamazaki, Katsuyuki

    In this paper, we have reported the development of a snowblower support system which can safely navigate snowblowers, even during a whiteout, with the combination of a very accurate GPS system, so called RTK-GPS, and a unique and highly accurate map of roadsides and obstacles on roads. Particularly emphasized new techniques in this paper are ways to detect accurate geographical positions of roadsides and obstacles by utilizing and analyzing 3D laser scanned data, whose data has become available in recent days. The experiment has shown that the map created by the methods and RTK-GPS can sufficiently navigate snowblowers, whereby a secure and pleasant social environment can be archived in snow areas of Japan. In addition, proposed methods are expected to be useful for other systems such as a quick development of a highly accurate road map, a safely navigation of a wheeled chair, and so on.

  4. Numerical simulation of pulsation processes in hydraulic turbine based on 3D model of cavitating flow

    NASA Astrophysics Data System (ADS)

    Panov, L. V.; Chirkov, D. V.; Cherny, S. G.; Pylev, I. M.

    2014-01-01

    A new approach was proposed for simulation of unsteady cavitating flow in the flow passage of a hydraulic power plant. 1D hydro-acoustics equations are solved in the penstock domain. 3D equations of turbulent flow of isothermal compressible liquid-vapor mixture are solved in the turbine domain. Cavitation is described by a transfer equation for liquid phase with a source term which is responsible for evaporation and condensation. The developed method was applied for simulation of pulsations in pressure, discharge, and total energy propagating along the flow conduit of the hydraulic power plant. Simulation results are in qualitative and quantitative agreement with experiment. The influence of key physical and numerical parameters like discharge, cavitation number, penstock length, time step, and vapor density on simulation results was studied.

  5. Seismic body-wave interferometry using noise autocorrelations for crustal structure and a tutorial on 3D seismic processing and imaging using Madagascar

    NASA Astrophysics Data System (ADS)

    Olejnik, Peter

    Seismic body-wave interferometry is applied to selected seismic stations from the USArray Earthscope Transportable Array (TA) by autocorrelating ambient seismic noise recordings to construct effective zero-offset reflection seismograms. The robustness of the auto-correlations of noise traces is first tested on a TA station in Nevada where body-wave reflections similar to those found in an earlier study are identified. This approach is then applied to several TA stations in the central U.S., and the results are compared with synthetic data. Different stacking time periods are then examined to find the shortest time intervals that provide stable correlation stacks. A tutorial on 3D seismic processing and imaging using the Madagascar open-source software package is next presented for educational purposes. The 3D Teapot Dome seismic data set is examined to illustrate the processing and imaging steps. A number of processing steps are applied to the data set, including amplitude gaining, muting, deconvolution, static corrections, velocity analysis, normal moveout (NMO) correction, and stacking. Post-stack time and depth migrations are then performed on the stacked data along with post-migration f-x deconvolution.

  6. Three-dimensional analysis of alveolar bone resorption by image processing of 3-D dental CT images

    NASA Astrophysics Data System (ADS)

    Nagao, Jiro; Kitasaka, Takayuki; Mori, Kensaku; Suenaga, Yasuhito; Yamada, Shohzoh; Naitoh, Munetaka

    2006-03-01

    We have developed a novel system that provides total support for assessment of alveolar bone resorption, caused by periodontitis, based on three-dimensional (3-D) dental CT images. In spite of the difficulty in perceiving the complex 3-D shape of resorption, dentists assessing resorption location and severity have been relying on two-dimensional radiography and probing, which merely provides one-dimensional information (depth) about resorption shape. However, there has been little work on assisting assessment of the disease by 3-D image processing and visualization techniques. This work provides quantitative evaluation results and figures for our system that measures the three-dimensional shape and spread of resorption. It has the following functions: (1) measures the depth of resorption by virtually simulating probing in the 3-D CT images, taking advantage of image processing of not suffering obstruction by teeth on the inter-proximal sides and much smaller measurement intervals than the conventional examination; (2) visualizes the disposition of the depth by movies and graphs; (3) produces a quantitative index and intuitive visual representation of the spread of resorption in the inter-radicular region in terms of area; and (4) calculates the volume of resorption as another severity index in the inter-radicular region and the region outside it. Experimental results in two cases of 3-D dental CT images and a comparison of the results with the clinical examination results and experts' measurements of the corresponding patients confirmed that the proposed system gives satisfying results, including 0.1 to 0.6mm of resorption measurement (probing) error and fairly intuitive presentation of measurement and calculation results.

  7. 3-D deformation rates and processes driving seismicity in the Western Alps and Pyrenees (southern France, northern Spain, northern Italy)

    NASA Astrophysics Data System (ADS)

    Vernant, Philippe; Mazzotti, Stephane; Masson, Christine; Ninh NGuyen, Hai; Doerflinger, Erik; Chéry, Jean; Khazaradze, Giorgi; Asensio, Eva

    2017-04-01

    Although subject to significant earthquakes, the region covering the Western Alps and Pyrenees in southern France, northern Spain, and northern Italy is characterized by very slow deformation rates (below 1 mm a-1), leading to ongoing debates regarding the driving processes and characteristics of this seismicity. We present a new 3-D velocity field for nearly 500 GPS sites covering this area, with two main objectives: (1) Precisely define the level of velocity and strain rate signals that can be extracted from the GPS data, and (2) Characterize the patterns and amplitude of present-day deformation in both the Western Alps and Pyrenees to help constrain the geodynamic processes at play. Statistical analyses of the GPS time series shows that a horizontal (resp. vertical) precision level of 0.2 mm a-1 can be achieved for series of 6 years (resp. 9 years), and that the velocity field for the entire Western Alps - Pyrenees region is stable at 0.2 mm a-1, indicating that horizontal deformation, where present, must be below this threshold. Significant horizontal strain rates are detected in the western Pyrenees, with up to 4 × 10-9 a-1 NNE-SSW extension, and to a lower level in the Western Alps (< 1 × 10-9 a-1 E-W extension). In contrast, we identify significant uplift rates in the Western Alps (up to 2 mm a-1) but not in the Pyrenees (0.1 ± 0.2 mm a-1). As shown by numerical models and by the correlation between site elevations and uplift rates, fast uplift in the northern part of the Western Alps can be explained for the most part by postglacial rebound following the Würm glaciation. In contrast, the very slow uplift rates in the southern Western Alps and in the Pyrenees may be accounted for by erosion-induced rebound. These results suggest that the primary driving mechanisms for present-day seismicity in the Western Alps, the Pyrenees, and their foreland basins may be visco-elastic rebound. Other processes, such as regional tectonics, post-orogenic collapse, or

  8. Tectonic drivers of the Wrangell block: Insights on fore-arc sliver processes from 3-D geodynamic models of Alaska

    NASA Astrophysics Data System (ADS)

    Haynie, K. L.; Jadamec, M. A.

    2017-07-01

    Intracontinental shear zones can play a key role in understanding how plate convergence is manifested in the upper plate in regions of oblique subduction. However, the relative role of the driving forces from the subducting plate and the resisting force from within intracontinental shear zones is not well understood. Results from high-resolution, geographically referenced, instantaneous 3-D geodynamic models of flat slab subduction at the oblique convergent margin of Alaska are presented. These models investigate how viscosity and length of the Denali fault intracontinental shear zone as well as coupling along the plate boundary interface modulate motion of the Wrangell block fore-arc sliver and slip across the Denali fault. Models with a weak Denali fault (1017 Pa s) and strong plate coupling (1021 Pa s) were found to produce the fastest motions of the Wrangell block (˜10 mm/yr). The 3-D models predict along-strike variation in motion along the Denali fault, changing from dextral strike-slip motion in the eastern segment to oblique convergence toward the fault apex. Models further show that the flat slab drives oblique motion of the Wrangell block and contributes to 20% (models with a short fault) and 28% (models with a long fault) of the observed Quaternary slip rates along the Denali fault. The 3-D models provide insight into the general processes of fore-arc sliver mechanics and also offer a 3-D framework for interpreting hazards in regions of flat slab subduction.

  9. Fabrication of 3D fine scale PZT components by ink-jet prototyping process

    NASA Astrophysics Data System (ADS)

    Noguera, R.; Dossou-Yovo, C.; Lejeune, M.; Chartier, T.

    2005-09-01

    Different investigations have been carried out to optimize an ink-jet printing technique, devoted to the fabrication of 3D fine scale PZT parts, by adjustment of the fluid properties of the ceramic suspensions and by controlling the ejection and impact phenomena. A 10 vol% PZT loaded suspension characterized by a Newtonian behavior, corresponding to a viscosity of 10mPa.s and to a ratio Re/We1/2 of 5.98 has been selected. The ejection and impact phenomena strongly depend on the driving parameters of the printing head, in particular the formation of the droplet, with satellite or not, as well as its velocity and volume which are function of the pulse amplitude. Moreover, the conditions of ejection (droplet velocity and volume) control the characteristics of the deposit (definition, spreading, thickness uniformity). Sintered PZT pillar array has been achieved by ink-jet printing with a definition equal to 50μm. These structures could be very useful to improve the performances of 1-3 ceramic polymer composites for imaging probes or more generally for ultrasonic transducers and also of micro-deformable mirrors for optical adaptive systems.

  10. 3D Markov Process for Traffic Flow Prediction in Real-Time

    PubMed Central

    Ko, Eunjeong; Ahn, Jinyoung; Kim, Eun Yi

    2016-01-01

    Recently, the correct estimation of traffic flow has begun to be considered an essential component in intelligent transportation systems. In this paper, a new statistical method to predict traffic flows using time series analyses and geometric correlations is proposed. The novelty of the proposed method is two-fold: (1) a 3D heat map is designed to describe the traffic conditions between roads, which can effectively represent the correlations between spatially- and temporally-adjacent traffic states; and (2) the relationship between the adjacent roads on the spatiotemporal domain is represented by cliques in MRF and the clique parameters are obtained by example-based learning. In order to assess the validity of the proposed method, it is tested using data from expressway traffic that are provided by the Korean Expressway Corporation, and the performance of the proposed method is compared with existing approaches. The results demonstrate that the proposed method can predict traffic conditions with an accuracy of 85%, and this accuracy can be improved further. PMID:26821025

  11. 3D-ICML: A 3D Bipolar ReRAM Design with Interleaved Complementary Memory Layers

    DTIC Science & Technology

    2013-05-01

    CONFERENCE PAPER (Post Print ) 3. DATES COVERED (From - To) DEC 2010 – NOV 2012 4. TITLE AND SUBTITLE 3D -ICML: A 3D BIPOLAR RERAM DESIGN WITH...three-dimensional ( 3D ) bipolar RRAM design, an isolation layer is inserted between two adjacent memory layers. The fabrication of the isolation layer...introduces the extra process complexity, increases fabrication cost, and causes some potential reliability issues. In this paper, we propose a 3D

  12. 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.

  13. 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

  14. Development of a 3D ultrasound system to investigate post-hemorrhagic hydrocephalus in pre-term neonates

    NASA Astrophysics Data System (ADS)

    Kishimoto, J.; Lee, D.; St. Lawrence, K.; Romano, W.; Fenster, A.; de Ribaupierre, S.

    2013-03-01

    Clinical intracranial ultrasound (US) is performed as a standard of care on neonates at risk of intraventricular hemorrhaging (IVH) and is also used after a diagnosis to monitor for potential ventricular dilation. However, it is difficult to estimate the volume of ventricles with 2D US due to their irregular shape. We developed a 3D US system to be used as an adjunct to a clinical system to investigate volumetric changes in the ventricles of neonates with IVH. Our system has been found have an error of within 1% of actual distance measurements in all three directions and volume measurements of manually segmented volumes from phantoms were not statistically significantly different from the actual values (p>0.3). Interobserver volume measurements of the lateral ventricles in a patient with grade III IVH found no significant differences between measurements. There is the potential to use this system in IVH patients to monitor the progression of ventriculomegaly over time.

  15. A study on the influence of process parameters on the Mechanical Properties of 3D printed ABS composite

    NASA Astrophysics Data System (ADS)

    Jaya Christiyan, K. G.; Chandrasekhar, U.; Venkateswarlu, K.

    2016-02-01

    Additive Manufacturing (AM) technologies have been emerged as a fabrication method to obtain engineering components within a short span of time. Desktop 3D printing, also referred as additive layer manufacturing technology is one of the powerful method of rapid prototyping (RP) technique that fabricates three dimensional engineering components. In this method, 3D digital CAD data is converted directly to a product. In the present investigation, ABS + hydrous magnesium silicate composite was considered as the starting material. Mechanical properties of ABS + hydrous magnesium silicate composite material were evaluated. ASTM D638 and ASTM D760 standards were followed for carrying out tensile and flexural tests, respectively. Samples with different layer thickness and printing speed were prepared. Based on the experimental results, it is suggested that low printing speed, and low layer thickness has resulted maximum tensile and flexural strength, as compared to all the other process parameters samples.

  16. Biomechanical Evaluation of a Tooth Restored with High Performance Polymer PEKK Post-Core System: A 3D Finite Element Analysis.

    PubMed

    Lee, Ki-Sun; Shin, Joo-Hee; Kim, Jong-Eun; Kim, Jee-Hwan; Lee, Won-Chang; Shin, Sang-Wan; Lee, Jeong-Yol

    2017-01-01

    The aim of this study was to evaluate the biomechanical behavior and long-term safety of high performance polymer PEKK as an intraradicular dental post-core material through comparative finite element analysis (FEA) with other conventional post-core materials. A 3D FEA model of a maxillary central incisor was constructed. A cyclic loading force of 50 N was applied at an angle of 45° to the longitudinal axis of the tooth at the palatal surface of the crown. For comparison with traditionally used post-core materials, three materials (gold, fiberglass, and PEKK) were simulated to determine their post-core properties. PEKK, with a lower elastic modulus than root dentin, showed comparably high failure resistance and a more favorable stress distribution than conventional post-core material. However, the PEKK post-core system showed a higher probability of debonding and crown failure under long-term cyclic loading than the metal or fiberglass post-core systems.

  17. Biomechanical Evaluation of a Tooth Restored with High Performance Polymer PEKK Post-Core System: A 3D Finite Element Analysis

    PubMed Central

    Shin, Joo-Hee; Kim, Jong-Eun; Kim, Jee-Hwan; Lee, Won-Chang; Shin, Sang-Wan

    2017-01-01

    The aim of this study was to evaluate the biomechanical behavior and long-term safety of high performance polymer PEKK as an intraradicular dental post-core material through comparative finite element analysis (FEA) with other conventional post-core materials. A 3D FEA model of a maxillary central incisor was constructed. A cyclic loading force of 50 N was applied at an angle of 45° to the longitudinal axis of the tooth at the palatal surface of the crown. For comparison with traditionally used post-core materials, three materials (gold, fiberglass, and PEKK) were simulated to determine their post-core properties. PEKK, with a lower elastic modulus than root dentin, showed comparably high failure resistance and a more favorable stress distribution than conventional post-core material. However, the PEKK post-core system showed a higher probability of debonding and crown failure under long-term cyclic loading than the metal or fiberglass post-core systems. PMID:28386547

  18. Reconstruction for Time-Domain In Vivo EPR 3D Multigradient Oximetric Imaging—A Parallel Processing Perspective

    PubMed Central

    Dharmaraj, Christopher D.; Thadikonda, Kishan; Fletcher, Anthony R.; Doan, Phuc N.; Devasahayam, Nallathamby; Matsumoto, Shingo; Johnson, Calvin A.; Cook, John A.; Mitchell, James B.; Subramanian, Sankaran; Krishna, Murali C.

    2009-01-01

    Three-dimensional Oximetric Electron Paramagnetic Resonance Imaging using the Single Point Imaging modality generates unpaired spin density and oxygen images that can readily distinguish between normal and tumor tissues in small animals. It is also possible with fast imaging to track the changes in tissue oxygenation in response to the oxygen content in the breathing air. However, this involves dealing with gigabytes of data for each 3D oximetric imaging experiment involving digital band pass filtering and background noise subtraction, followed by 3D Fourier reconstruction. This process is rather slow in a conventional uniprocessor system. This paper presents a parallelization framework using OpenMP runtime support and parallel MATLAB to execute such computationally intensive programs. The Intel compiler is used to develop a parallel C++ code based on OpenMP. The code is executed on four Dual-Core AMD Opteron shared memory processors, to reduce the computational burden of the filtration task significantly. The results show that the parallel code for filtration has achieved a speed up factor of 46.66 as against the equivalent serial MATLAB code. In addition, a parallel MATLAB code has been developed to perform 3D Fourier reconstruction. Speedup factors of 4.57 and 4.25 have been achieved during the reconstruction process and oximetry computation, for a data set with 23 × 23 × 23 gradient steps. The execution time has been computed for both the serial and parallel implementations using different dimensions of the data and presented for comparison. The reported system has been designed to be easily accessible even from low-cost personal computers through local internet (NIHnet). The experimental results demonstrate that the parallel computing provides a source of high computational power to obtain biophysical parameters from 3D EPR oximetric imaging, almost in real-time. PMID:19672315

  19. Build Angle: Does It Influence the Accuracy of 3D-Printed Dental Restorations Using Digital Light-Processing Technology?

    PubMed

    Osman, Reham B; Alharbi, Nawal; Wismeijer, Daniel

    The aim of this study was to evaluate the effect of the build orientation/build angle on the dimensional accuracy of full-coverage dental restorations manufactured using digital light-processing technology (DLP-AM). A full dental crown was digitally designed and 3D-printed using DLP-AM. Nine build angles were used: 90, 120, 135, 150, 180, 210, 225, 240, and 270 degrees. The specimens were digitally scanned using a high-resolution optical surface scanner (IScan D104i, Imetric). Dimensional accuracy was evaluated using the digital subtraction technique. The 3D digital files of the scanned printed crowns (test model) were exported in standard tessellation language (STL) format and superimposed on the STL file of the designed crown [reference model] using Geomagic Studio 2014 (3D Systems). The root mean square estimate (RMSE) values were evaluated, and the deviation patterns on the color maps were further assessed. The build angle influenced the dimensional accuracy of 3D-printed restorations. The lowest RMSE was recorded for the 135-degree and 210-degree build angles. However, the overall deviation pattern on the color map was more favorable with the 135-degree build angle in contrast with the 210-degree build angle where the deviation was observed around the critical marginal area. Within the limitations of this study, the recommended build angle using the current DLP system was 135 degrees. Among the selected build angles, it offers the highest dimensional accuracy and the most favorable deviation pattern. It also offers a self-supporting crown geometry throughout the building process.

  20. Processing and Evaluation of 3D-Reinforced Needled Composite Laminate

    DTIC Science & Technology

    2012-09-01

    This report documents the fabrication and test of a woven glass /epoxy composite laminate that was reinforced in the through- thickness direction with...the in-plane strength of woven glass materials. Because the processing parameters were arbitrarily chosen, these experiments should be considered as...delamination resistance of composite laminates. The tufting process uses a hollow needle to insert glass or carbon threads comprised of typically

  1. Taking geoscience to the IMAX: 3D and 4D insight into geological processes using micro-CT

    NASA Astrophysics Data System (ADS)

    Dobson, Katherine; Dingwell, Don; Hess, Kai-Uwe; Withers, Philip; Lee, Peter; Pistone, Mattia; Fife, Julie; Atwood, Robert

    2015-04-01

    Geology is inherently dynamic, and full understanding of any geological system can only be achieved by considering the processes by which change occurs. Analytical limitations mean understanding has largely developed from ex situ analyses of the products of geological change, rather than of the processes themselves. Most methods essentially utilise "snap shot" sampling: and from thin section petrography to high resolution crystal chemical stratigraphy and field volcanology, we capture an incomplete view of a spatially and temporally variable system. Even with detailed experimental work, we can usually only analyse samples before and after we perform an experiment, as routine analysis methods are destructive. Serial sectioning and quenched experiments stopped at different stages can give some insight into the third and fourth dimension, but the true scaling of the processes from the laboratory to the 4D (3D + time) geosphere is still poorly understood. Micro computed tomography (XMT) can visualise the internal structures and spatial associations within geological samples non-destructively. With image resolutions of between 200 microns and 50 nanometres, tomography has the ability to provide a detailed sample assessment in 3D, and quantification of mineral associations, porosity, grain orientations, fracture alignments and many other features. This allows better understanding of the role of the complex geometries and associations within the samples, but the challenge of capturing the processes that generate and modify these structures remains. To capture processes, recent work has focused on developing experimental capability for in situ experiments on geological materials. Data presented will showcase examples from recent experiments where high speed synchrotron x-ray tomography has been used to acquire each 3D image in under 2 seconds. We present a suite of studies that showcase how it is now possible to take quantification of many geological processed into 3D and

  2. Converted-Wave Processing of a 3D-3C Refection Seismic Survey of Soda Lake Geothermal Field

    NASA Astrophysics Data System (ADS)

    Louie, J. N.; Kent, T.; Echols, J.

    2012-12-01

    This 3D-3C seismic survey greatly improves the structural model of the Soda Lake, Nevada geothermal system. The picked top of a mudstone interval above reservoir levels reveals a detailed fault map. The geothermal reservoir is within a complex of nested grabens. Determining a "geothermal indicator" for the deeper reservoir in the seismic signal, and processing of the 3D converted-wave data, have been unsuccessful to date. Due to a high near-surface Vp/Vs ratio the shear-wave energy is under-sampled with 220 ft receiver spacing and 550 ft (168 m) line spacing. The 2D converted-wave data that we can image shows encouraging similarity to the deep structural features in the P-wave sections, but have little resolution of shallow structures. Higher-density receivers and a better shallow shear-wave model are needed in conjunction with this deep reflection study to effectively image the 3D converted waves.

  3. [Accuracy of optical scanning methods of the Cerec 3D system in the process of making ceramic inlays].

    PubMed

    Trifković, Branka; Todorović, Aleksandar; Lazić, Vojkan; Draganjac, Miroslav; Mirković, Nemanja; Jokić, Bojan

    2010-10-01

    One of the results of many years of Cerec 3D CAD/CAM system technological development is implementation of one intraoral and two extraoral optical scanning methods which, depending on the current indications, are applied in making fixed restorations. The aim of this study was to determine the degree of precision of optical scanning methods by the use of the Cerec 3D CAD/CAM system in the process of making ceramic inlays. The study was conducted in three experimental groups of inlays prepared using the procedure of three methods of scanning Cerec 3D system. Ceramic inlays made by conventional methodology were the control group. The accuracy of optical scanning methods of the Cerec 3D system computer aided design-computer aided manufacturing (CAD/CAM) was indirectly examined by measuring a marginal gap size between inlays and demarcation preparation by scanning electron microscope (SEM). The results of the study showed a difference in the accuracy of the existing methods of scanning dental CAD/CAM systems. The highest level of accuracy was achieved by the extraoral optical superficial scanning technique. The value of marginal gap size inlays made with the technique of extraoral optical superficial scanning was 32.97 +/- 13.17 mus. Techniques of intraoral optical superficial and extraoral point laser scanning showed a lower level of accuracy (40.29 +/- 21.46 mus for inlays of intraoral optical superficial scanning and 99.67 +/- 37.25 mus for inlays of extraoral point laser scanning). Optical scanning methods in dental CAM/CAM technologies are precise methods of digitizing the spatial models; application of extraoral optical scanning methods provides the highest precision.

  4. a Geometric Processing Workflow for Transforming Reality-Based 3d Models in Volumetric Meshes Suitable for Fea

    NASA Astrophysics Data System (ADS)

    Gonizzi Barsanti, S.; Guidi, G.

    2017-02-01

    Conservation of Cultural Heritage is a key issue and structural changes and damages can influence the mechanical behaviour of artefacts and buildings. The use of Finite Elements Methods (FEM) for mechanical analysis is largely used in modelling stress behaviour. The typical workflow involves the use of CAD 3D models made by Non-Uniform Rational B-splines (NURBS) surfaces, representing the ideal shape of the object to be simulated. Nowadays, 3D documentation of CH has been widely developed through reality-based approaches, but the models are not suitable for a direct use in FEA: the mesh has in fact to be converted to volumetric, and the density has to be reduced since the computational complexity of a FEA grows exponentially with the number of nodes. The focus of this paper is to present a new method aiming at generate the most accurate 3D representation of a real artefact from highly accurate 3D digital models derived from reality-based techniques, maintaining the accuracy of the high-resolution polygonal models in the solid ones. The approach proposed is based on a wise use of retopology procedures and a transformation of this model to a mathematical one made by NURBS surfaces suitable for being processed by volumetric meshers typically embedded in standard FEM packages. The strong simplification with little loss of consistency possible with the retopology step is used for maintaining as much coherence as possible between the original acquired mesh and the simplified model, creating in the meantime a topology that is more favourable for the automatic NURBS conversion.

  5. Learning process for performing and analyzing 3D/4D transperineal ultrasound imaging and interobserver reliability study.

    PubMed

    Siafarikas, F; Staer-Jensen, J; Braekken, I H; Bø, K; Engh, M Ellström

    2013-03-01

    To evaluate the learning process for acquiring three- and four-dimensional (3D/4D) transperineal ultrasound volumes of the levator hiatus (LH) dimensions at rest, during pelvic floor muscle (PFM) contraction and on Valsalva maneuver, and for analyzing the ultrasound volumes, as well as to perform an interobserver reliability study between two independent ultrasound examiners. This was a prospective study including 22 women. We monitored the learning process of an inexperienced examiner (IE) performing 3D/4D transperineal ultrasonography and analyzing the volumes. The examination included acquiring volumes during three PFM contractions and three Valsalva maneuvers. LH dimensions were determined in the axial plane. The learning process was documented by estimating agreement between the IE and an experienced examiner (E) using the intraclass correlation coefficient. Agreement was calculated in blocks of 10 ultrasound examinations and analyzed volumes. After the learning process was complete the interobserver reliability for the technique was calculated between these two independent examiners. For offline analysis of the first 10 ultrasound volumes obtained by E, good to very good agreement between E and IE was achieved for all LH measurements except for the left and right levator-urethra gap and pubic arc. For the next 10 analyzed volumes, agreement improved for all LH measurements. Volumes that had been obtained by IE and E were then re-evaluated by IE, and good to very good agreement was found for all LH measurements indicating consistency in volume acquisition. The interobserver reliability study showed excellent ICC values (ICC, 0.81-0.97) for all LH measurements except the pubic arc (ICC = 0.67). 3D/4D transperineal ultrasound is a reliable technique that can be learned in a short period of time. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.

  6. Numerical modeling of cutting processes for elastoplastic materials in 3D-statement

    NASA Astrophysics Data System (ADS)

    Kukudzhanov, V. N.; Levitin, A. L.

    2008-06-01

    In the present paper, we use the finite element method to perform the three-dimensional modeling of unsteady process of cutting an elastoplastic plate (slab) by an absolutely rigid cutting tool moving at a constant velocity V 0 at different inclinations α of the tool face (Fig. 1). The modeling was based on the coupled thermomechanical model of an elastoviscoplastic material. The adiabatic process of cutting was compared with the regime in which the slab material heat conduction is taken into account. The cutting process was parametrically studied for variations in the slab and cutting tool geometry, in the rate and depth of cutting, and in the properties of the processed material. The slab thickness was varied in the direction of the axis z. The stressed state varied from the plane-stressed bar H = H/L≪ 1 (thin plate) to the plane-strained bar H ≫ 1 (wide plate), where H is the slab thickness and L is the slab length. The problem was solved on a moving adaptive Lagrange-Euler grid by the finite element method with splitting, by using the explicit-implicit integration schemes for equations [13]. It was shown that the numerical modeling of the problem in the three-dimensional statement permits studying the cutting processes with continuous chip formation and with chip destruction into separate pieces. The mechanism of this phenomenon in the case of orthogonal cutting ( α = 0) can be explained by the thermal softening with formation of adiabatic shear strips without using the damage models. In cutting by a sharper tool (the angle α is large), it is necessary to use the coupled model of thermal and structural softening. We obtain dependences of the force acting on the tool for different geometric and physical parameters of the problem. We also show that the quasimonotone and oscillating operation modes are possible and explain them from the physical standpoint.

  7. Cross-correlative 3D micro-structural investigation of human bone processed into bone allografts.

    PubMed

    Singh, Atul Kumar; Gajiwala, Astrid Lobo; Rai, Ratan Kumar; Khan, Mohd Parvez; Singh, Chandan; Barbhuyan, Tarun; Vijayalakshmi, S; Chattopadhyay, Naibedya; Sinha, Neeraj; Kumar, Ashutosh; Bellare, Jayesh R

    2016-05-01

    Bone allografts (BA) are a cost-effective and sustainable alternative in orthopedic practice as they provide a permanent solution for preserving skeletal architecture and function. Such BA however, must be processed to be disease free and immunologically safe as well as biologically and clinically useful. Here, we have demonstrated a processing protocol for bone allografts and investigated the micro-structural properties of bone collected from osteoporotic and normal human donor samples. In order to characterize BA at different microscopic levels, a combination of techniques such as Solid State Nuclear Magnetic Resonance (ssNMR), Scanning Electron Microscope (SEM), micro-computed tomography (μCT) and Thermal Gravimetric Analysis (TGA) were used for delineating the ultra-structural property of bone. ssNMR revealed the extent of water, collagen fine structure and crystalline order in the bone. These were greatly perturbed in the bone taken from osteoporotic bone donor. Among the processing methods analyzed, pasteurization at 60 °C and radiation treatment appeared to substantially alter the bone integrity. SEM study showed a reduction in Ca/P ratio and non-uniform distribution of elements in osteoporotic bones. μ-CT and MIMICS (Materialize Interactive Medical Image Control System) demonstrated that pasteurization and radiation treatment affects the BA morphology and cause a shift in the HU unit. However, the combination of all these processes restored all-important parameters that are critical for BA integrity and sustainability. Cross-correlation between the various probes we used quantitatively demonstrated differences in morphological and micro-structural properties between BA taken from normal and osteoporotic human donor. Such details could also be instrumental in designing an appropriate bone scaffold. For the best restoration of bone microstructure and to be used as a biomaterial allograft, a step-wise processing method is recommended that preserves all

  8. Simulation of the enhancement factor from an individual 3D hemisphere-on-post field emitter by using finite elements method.

    PubMed

    Roveri, D S; Sant'Anna, G M; Bertan, H H; Mologni, J F; Alves, M A R; Braga, E S

    2016-01-01

    This paper presents a 3D computational framework for evaluating electrostatic properties of a single field emitter characterized by the hemisphere-on-post geometry. Numerical simulations employed the finite elements method by using Ansys-Maxwell software. Extensive parametric simulations were focused on the threshold distance from which the emitter field enhancement factor (γ) becomes independent from the anode-substrate gap (G). This investigation allowed demonstrating that the ratio between G and the emitter height (h) is a reliable reference for a broad range of emitter dimensions; furthermore, results permitted establishing G/h ≥ 2.2 as the threshold condition for setting the anode without affecting γ.

  9. Novel Processing for Creating 3D Architectured Porous Shape Memory Alloy

    DTIC Science & Technology

    2013-03-01

    together with HIPing, liquid phase sintering was used. At 1150°C Nb forms a eutectic with binary NiTi. This eutectic is very reactive and dissolves...mechanical properties [6]. The eutectic phase has been shown to have high tensile strength bonding [7], and high wettability of NiTi. The liquid... eutectic wicks into space between powder particles, liquid sintering them together upon solidification. The liquid phase sintering processing method is

  10. Nanostructured Origami (Trademark) 3D Fabrication and Self Assembly Process for Soldier Combat Systems

    DTIC Science & Technology

    2004-12-01

    the Japanese art of “ origami ”) involves patterning adjacent 2D membranes that can be lifted off (using methods we have developed) of a silicon...innovative process holds immense potential for the Army’s Objective Force Warrior. Nanostructured Origami enables many practical and promising...Nanostructured Origami allows such devices to be formed from a single, micro/nanofabricated layer. In addition, nanoarchitecture can be added

  11. Processes of Equatorial Thermal Structure: An Analysis of Galileo Temperature Profile with 3-D Model

    NASA Technical Reports Server (NTRS)

    Majeed, T.; Waite, J. H., Jr.; Bougher, S. W.; Gladstone, G. R.

    2005-01-01

    The Jupiter Thermosphere General Circulation Model (JTGCM) calculates the global dynamical structure of Jupiter's thermosphere self-consistently with its global thermal structure and composition. The main heat source that drives the thermospheric flow is high-latitude Joule heating. A secondary source of heating is the auroral process of particle precipitation. Global simulations of Jovian thermospheric dynamics indicate strong neutral outflows from the auroral ovals with velocities up to approximately 2 kilometers per second and subsequent convergence and downwelling at the Jovian equator. Such circulation is shown to be an important process for transporting significant amounts of auroral energy to equatorial latitudes and for regulating the global heat budget in a manner consistent with the high thermospheric temperatures observed by the Galileo probe. Adiabatic compression of the neutral atmosphere resulting from downward motion is an important source of equatorial heating (less than 0.06 microbar). The adiabatic heating continues to dominate between 0.06 and 0.2 microbar, but with an addition of comparable heating due to horizontal advection induced by the meridional flow. Thermal conduction plays an important role in transporting heat down to lower altitudes (greater than 0.2microbar) where it is balanced by the cooling associated with the wind transport processes. Interestingly, we find that radiative cooling caused by H3(+), CH4, and C2H2 emissions does not play a significant role in interpreting the Galileo temperature profile.

  12. Tropical Oceanic Precipitation Processes Over Warm Pool: 2D and 3D Cloud Resolving Model Simulations

    NASA Technical Reports Server (NTRS)

    Tao, W.-K.; Johnson, D.; Simpson, J.; Einaudi, Franco (Technical Monitor)

    2001-01-01

    Rainfall is a key link in the hydrologic cycle as well as the primary heat source for the atmosphere. The vertical distribution of convective latent-heat release modulates the large-scale circulations of the topics. Furthermore, changes in the moisture distribution at middle and upper levels of the troposphere can affect cloud distributions and cloud liquid water and ice contents. How the incoming solar and outgoing longwave radiation respond to these changes in clouds is a major factor in assessing climate change. Present large-scale weather and climate model simulate processes only crudely, reducing confidence in their predictions on both global and regional scales. One of the most promising methods to test physical parameterizations used in General Circulation Models (GCMs) and climate models is to use field observations together with Cloud Resolving Models (CRMs). The CRMs use more sophisticated and physically realistic parameterizations of cloud microphysical processes, and allow for their complex interactions with solar and infrared radiative transfer processes. The CRMs can reasonably well resolve the evolution, structure, and life cycles of individual clouds and clouds systems. The major objective of this paper is to investigate the latent heating, moisture and momentum budgets associated with several convective systems developed during the TOGA COARE IFA - westerly wind burst event (late December, 1992). The tool for this study is the Goddard Cumulus Ensemble (GCE) model which includes a 3-class ice-phase microphysics scheme.

  13. Tropical Oceanic Precipitation Processes Over Warm Pool: 2D and 3D Cloud Resolving Model Simulations

    NASA Technical Reports Server (NTRS)

    Tao, W.-K.; Johnson, D.; Simpson, J.; Einaudi, Franco (Technical Monitor)

    2001-01-01

    Rainfall is a key link in the hydrologic cycle as well as the primary heat source for the atmosphere. The vertical distribution of convective latent-heat release modulates the large-scale circulations of the topics. Furthermore, changes in the moisture distribution at middle and upper levels of the troposphere can affect cloud distributions and cloud liquid water and ice contents. How the incoming solar and outgoing longwave radiation respond to these changes in clouds is a major factor in assessing climate change. Present large-scale weather and climate model simulate processes only crudely, reducing confidence in their predictions on both global and regional scales. One of the most promising methods to test physical parameterizations used in General Circulation Models (GCMs) and climate models is to use field observations together with Cloud Resolving Models (CRMs). The CRMs use more sophisticated and physically realistic parameterizations of cloud microphysical processes, and allow for their complex interactions with solar and infrared radiative transfer processes. The CRMs can reasonably well resolve the evolution, structure, and life cycles of individual clouds and clouds systems. The major objective of this paper is to investigate the latent heating, moisture and momentum budgets associated with several convective systems developed during the TOGA COARE IFA - westerly wind burst event (late December, 1992). The tool for this study is the Goddard Cumulus Ensemble (GCE) model which includes a 3-class ice-phase microphysics scheme.

  14. Fluid Flow Processes Study: from a 3D seismic data set in the Pointer Ridge offshore SW Taiwan

    NASA Astrophysics Data System (ADS)

    Han, Wei-Chung; Liu, Char-Shine; Chen, Liwen; Chi, Wu-Cheng; Lin, Che-Chuan

    2016-04-01

    This study analyzes a 3D seismic cube in the Pointer Ridge for understanding the fluid flow processes in subsurface. Pointer Ridge is a ridge situated on the passive China continental margin and is suggested as a potential prospect for future gas hydrate development. High methane flux rate, active gas venting and seismic chimneys have been observed in this area, which are direct evidences for active ongoing fluid migration processes. To find the possible fluid conduits and to understand how the fluids have migrated along those conduits, we firstly identify the structural and sedimentary features from this 3D seismic cube in our study area. Secondly, seismic attribute analyses are carried out for detecting fluid conduits and evaluating the contribution of recognized faults/fractures for fluid flow, respectively. Finally, we propose conceptual models to illustrate how fluids have migrated along those conduits to the seafloor and how those conduits have developed. The results show: 1) a major NE-SW striking normal fault (PR Fault) separates a depositional field on the hanging wall and a erosional field on the footwall; 2) the PR Fault zone itself and the chimneys in its footwall act as main conduits for focused fluid flow migrating to the seafloor; 3) the development of the chimneys in the Pointer Ridge area are highly controlled by the erosion and deposition processes. Since the ongoing fluid flow processes will increase the seafloor instabilities and the Pointer Ridge is a gas hydrate leaking site, our results could provide useful information for further risk evaluation.

  15. The Influence of Process Parameters on the Characteristics of Electrospun 3D Nanostructures

    NASA Astrophysics Data System (ADS)

    Bertea, A.; Manea, L. R.; Popa, A.; Bertea, A.

    2017-06-01

    Electrospinning is a fast developing technique that employs electrostatic repulsive forces to produce ultrafine fibres with application in fields like environment protection, medicine, sensors and many others. The characteristics of the polymer jet and the properties of the electrospun nanofibres are highly influenced by technological and environmental parameters. This paper offers a report on the main processing parameters that may influence the characteristics of the obtained nanofibres. The influence of flow rate, spinneret to collector distance and applied voltage on maximum fibre length, average fibre diameter, diameter uniformity and nanofibre quality is reviewed.

  16. Fabrication 3D buried channel optical waveguide modulators on field-driven ion exchange process

    NASA Astrophysics Data System (ADS)

    Zhou, Zigang; Chen, Wenqiang; Zhu, Li; Li, Jing; Luo, Xiaoying

    2010-10-01

    A high electric field technique was developed to fabricate buried optical waveguide modulator on K9 optical glass. The 80V voltage was applied on the glass to accelerate the field-driven ion exchange process by expeditiously replacing host sodium ions in the glass with silver ions. As a result, the optical loss for optical waveguide modulator was measured using the edge coupling technique with a 0.6328μm He-Ne laser. Loss of 0.20 dB/cm was obtained for channel waveguides of 25μm in depth, relatively low for waveguides of such depth at red wavelength.

  17. Built-in test equipment of a 3-D radar signal processing

    NASA Astrophysics Data System (ADS)

    Boulin, M.

    The built-in test equipment (BITE) of a digital signal processing in a long-range three-dimensional radar is presented. The main BITE functions are summarized and its principle is described. The latter involves the integration of pseudorandom generation of test data into logic cards and the compression of responses into a signature. The implementation of BITEs using BILBOs (built-in logic block observers) and system BITE implementation are addressed. Software organization and the control of the external signature analyzer are discussed, and performance characteristics are presented.

  18. 3D polylactide-based scaffolds for studying human hepatocarcinoma processes in vitro.

    PubMed

    Scaffaro, Roberto; Re, Giada Lo; Rigogliuso, Salvatrice; Ghersi, Giulio

    2012-08-01

    We evaluated the combination of leaching techniques and melt blending of polymers and particles for the preparation of highly interconnected three-dimensional polymeric porous scaffolds for in vitro studies of human hepatocarcinoma processes. More specifically, sodium chloride and poly(ethylene glycol) (PEG) were used as water-soluble porogens to form porous and solvent-free poly(L,D-lactide) (PLA)-based scaffolds. Several characterization techniques, including porosimetry, image analysis and thermogravimetry, were combined to improve the reliability of measurements and mapping of the size, distribution and microarchitecture of pores. We also investigated the effect of processing, in PLA-based blends, on the simultaneous bulk/surface modifications and pore architectures in the scaffolds, and assessed the effects on human hepatocarcinoma viability and cell adhesion. The influence of PEG molecular weight on the scaffold morphology and cell viability and adhesion were also investigated. Morphological studies indicated that it was possible to obtain scaffolds with well-interconnected pores of assorted sizes. The analysis confirmed that SK-Hep1 cells adhered well to the polymeric support and emitted surface protrusions necessary to grow and differentiate three-dimensional systems. PEGs with higher molecular weight showed the best results in terms of cell adhesion and viability.

  19. Modeling Anisotropic Plasticity: 3D Eulerian Hydrocode Simulations of High Strain Rate Deformation Processes

    NASA Astrophysics Data System (ADS)

    Burkett, Michael; Clancy, Sean; Maudlin, Paul; Holian, Kathleen

    2001-06-01

    : Previously developed constitutive models and solution algorithms for anisotropic elastoplastic material strength has been implemented in the three-dimensional CONEJO hydrodynamics code. CONEJO is an explicit, Eulerian continuum mechanics code that is utilized to predict formation processes associated with material deformation at elevated strain-rates and is a code development project under the Accelerated Strategic Computing Initiative (ASCI) program. Some special features of CONEJO include a high-order advection algorithm, a material interface tracking scheme, and van Leer monotonic advection-limiting. The anisotropic constitutive modeling is posed in an unrotated material frame using the theorem of polar decomposition to describe rigid body rotation. An Euler-Rodrigues description is used to quantify the rigid body rotations. Continuous quadratic yield functions fitted from polycrystal simulations for a metallic hexagonal-close-packed structure were utilized. Associative flow formulations incorporating these yield functions were solved using a geometric normal return method. Simple rectangular shear problems, "R-value" problems, and Taylor cylinder impact test data were utilized to verify and validate the implementation of the anisotropic model. A "stretching rod" problem (involving large strain and strain-rate deformation) was selected to investigate the effects of material anisotropy for this deformation process. The rod necking rate and topology was compared for CONEJO simulations using several isotropic and anisotropic descriptions that utilized the Mechanical Threshold Stress (MTS) model.

  20. Processing and properties of arsenic trisulfide chalcogenide glasses for direct laser writing of 3D microstructures

    NASA Astrophysics Data System (ADS)

    Schwarz, Casey M.; Williams, Henry E.; Grabill, Chris N.; Lewis, Anna M.; Kuebler, Stephen M.; Gleason, Benn; Richardson, Kathleen A.; Pogrebnyakov, Alexej; Mayer, Theresa S.; Drake, Christina; Rivero-Baleine, Clara

    2014-03-01

    Arsenic trisulfide (As2S3) is a transparent material from ~620 nm to 11 μm with direct applications in sensors, photonic waveguides, and acousto-optics. As2S3 may be thermally deposited to form glassy films of molecular chalcogenide (ChG) clusters. It has been shown that linear and multi-photon exposure can be used to photo-pattern thermally deposited As2S3. Photo-exposure cross-links the film into a network solid. Treating the photo-patterned material with a polarsolvent removes the unexposed material leaving behind a structure that is a negative-tone replica of the photo-pattern. In this work, nano-structure arrays were photo-patterned in As2S3 films by multi-photon direct laser writing (DLW) and the resulting structure, morphology, and chemical composition were characterized and correlated with the conditions of the thermal deposition, patterned irradiation, and etch processing. Raman spectroscopy was used to characterize the chemical structure of the unexposed and photo-exposed material, and near infrared ellipsometry was used to measure the refractive index. Physical characterization including structure size and surface adhesion of nano-scale features is related to the processing conditions.

  1. 3D polylactide-based scaffolds for studying human hepatocarcinoma processes in vitro

    NASA Astrophysics Data System (ADS)

    Scaffaro, Roberto; Lo Re, Giada; Rigogliuso, Salvatrice; Ghersi, Giulio

    2012-08-01

    We evaluated the combination of leaching techniques and melt blending of polymers and particles for the preparation of highly interconnected three-dimensional polymeric porous scaffolds for in vitro studies of human hepatocarcinoma processes. More specifically, sodium chloride and poly(ethylene glycol) (PEG) were used as water-soluble porogens to form porous and solvent-free poly(L,D-lactide) (PLA)-based scaffolds. Several characterization techniques, including porosimetry, image analysis and thermogravimetry, were combined to improve the reliability of measurements and mapping of the size, distribution and microarchitecture of pores. We also investigated the effect of processing, in PLA-based blends, on the simultaneous bulk/surface modifications and pore architectures in the scaffolds, and assessed the effects on human hepatocarcinoma viability and cell adhesion. The influence of PEG molecular weight on the scaffold morphology and cell viability and adhesion were also investigated. Morphological studies indicated that it was possible to obtain scaffolds with well-interconnected pores of assorted sizes. The analysis confirmed that SK-Hep1 cells adhered well to the polymeric support and emitted surface protrusions necessary to grow and differentiate three-dimensional systems. PEGs with higher molecular weight showed the best results in terms of cell adhesion and viability.

  2. Editorial: 3DIM-DS 2015: Optical image processing in the context of 3D imaging, metrology, and data security

    NASA Astrophysics Data System (ADS)

    Alfalou, Ayman

    2017-02-01

    Following the first International Symposium on 3D Imaging, Metrology, and Data Security (3DIM-DS) held in Shenzhen during september 2015, this special issue gathers a series of articles dealing with the main topics discussed during this symposium. These topics highlighted the importance of studying complex data treatment systems and intensive calculations designed for high dimensional imaging and metrology for which high image quality and high transmission speed become critical issues in a number of technological applications. A second purpose was to celebrate the International Year of Light by emphasizing the important role of optics in actual information processing systems.

  3. From 3D view to 3D print

    NASA Astrophysics Data System (ADS)

    Dima, M.; Farisato, G.; Bergomi, M.; Viotto, V.; Magrin, D.; Greggio, D.; Farinato, J.; Marafatto, L.; Ragazzoni, R.; Piazza, D.

    2014-08-01

    In the last few years 3D printing is getting more and more popular and used in many fields going from manufacturing to industrial design, architecture, medical support and aerospace. 3D printing is an evolution of bi-dimensional printing, which allows to obtain a solid object from a 3D model, realized with a 3D modelling software. The final product is obtained using an additive process, in which successive layers of material are laid down one over the other. A 3D printer allows to realize, in a simple way, very complex shapes, which would be quite difficult to be produced with dedicated conventional facilities. Thanks to the fact that the 3D printing is obtained superposing one layer to the others, it doesn't need any particular work flow and it is sufficient to simply draw the model and send it to print. Many different kinds of 3D printers exist based on the technology and material used for layer deposition. A common material used by the toner is ABS plastics, which is a light and rigid thermoplastic polymer, whose peculiar mechanical properties make it diffusely used in several fields, like pipes production and cars interiors manufacturing. I used this technology to create a 1:1 scale model of the telescope which is the hardware core of the space small mission CHEOPS (CHaracterising ExOPlanets Satellite) by ESA, which aims to characterize EXOplanets via transits observations. The telescope has a Ritchey-Chrétien configuration with a 30cm aperture and the launch is foreseen in 2017. In this paper, I present the different phases for the realization of such a model, focusing onto pros and cons of this kind of technology. For example, because of the finite printable volume (10×10×12 inches in the x, y and z directions respectively), it has been necessary to split the largest parts of the instrument in smaller components to be then reassembled and post-processed. A further issue is the resolution of the printed material, which is expressed in terms of layers

  4. Laser processing system for stitching structured patterns on large 3D parts

    NASA Astrophysics Data System (ADS)

    Cano Zuriguel, Rafael; Saludes Rodil, Sergio

    2015-07-01

    The paper addresses the development of laser based equipment to structure large surfaces (1×1×0.5m - 3×3×1.5ft) that are shaped in three dimensions. A mechanic-optical system to process curved surfaces with an acceptance angle of up to 267° is presented. The challenge is to control the combined motion of the beam delivery system with respect to distortion of the motifs and positioning tolerances. The project starting Technology Readiness Level (TRL) was 5. Currently the project is under development and at the end of September 2015 the project will reach TRL 7 after industrial-like environment testing. The proposed system will enable manufacturers to offer individualized marking for large products.

  5. Segmentation-free image processing and analysis of precipitate shapes in 2D and 3D

    NASA Astrophysics Data System (ADS)

    Bales, Ben; Pollock, Tresa; Petzold, Linda

    2017-06-01

    Segmentation based image analysis techniques are routinely employed for quantitative analysis of complex microstructures containing two or more phases. The primary advantage of these approaches is that spatial information on the distribution of phases is retained, enabling subjective judgements of the quality of the segmentation and subsequent analysis process. The downside is that computing micrograph segmentations with data from morphologically complex microstructures gathered with error-prone detectors is challenging and, if no special care is taken, the artifacts of the segmentation will make any subsequent analysis and conclusions uncertain. In this paper we demonstrate, using a two phase nickel-base superalloy microstructure as a model system, a new methodology for analysis of precipitate shapes using a segmentation-free approach based on the histogram of oriented gradients feature descriptor, a classic tool in image analysis. The benefits of this methodology for analysis of microstructure in two and three-dimensions are demonstrated.

  6. Importance of 3D Processes Near the Ocean's Surface for Material Transport

    NASA Astrophysics Data System (ADS)

    Ozgokmen, T. M.

    2014-12-01

    There are a number of practical problems that demand an accurate knowledge of ocean currents near the surface of the ocean. It is known that oceanic coherent features transport heat and carry out vertical exchange of biogeochemical tracers. Ocean currents can affect biological primary production, air-sea gas exchanges and global tracer budgets. Ocean currents are also important for the dispersion of substances that pose a danger to society, economy and human health. Examples of such events include algal blooms, the Fukushima nuclear plant incident in the Pacific Ocean in 2011, and repeated large oil spills in the Gulf of Mexico, namely the IXTOC in 1978 and the Deepwater Horizon event in 2010. Such incidents demand accurate answers to questions such as ``where will the pollutant go?", ``how fast will it get there?" and ``how much pollutant will arrive there?", and in some instances ``where did the pollutant come from?". The answers to these questions are critical to the allocation of limited response resources, and in determining the overall impact of the events. We will summarize the efforts by the Consortium for Advanced Research on Transport of Hydrocarbon in the Environment (CARTHE). One of the primary objectives of CARTHE is to improve predictive modeling capability for flows near the air-sea interface. In particular, two large experiments, Grand Lagrangian Deployment (GLAD) and Surf-zone and Coastal Oil Pathways Experiment (SCOPE), coordinated with real-time modeling were instructive on processes influencing near-surface material transport. Findings on submesoscale flows as well as model deficiencies to capture processes relevant to transport will be discussed. Insight into future modeling and observational plans will be provided.

  7. Effect of fibre posts, bone losses and fibre content on the biomechanical behaviour of endodontically treated teeth: 3D-finite element analysis.

    PubMed

    Chieruzzi, Manila; Pagano, Stefano; Cianetti, Stefano; Lombardo, Guido; Kenny, José M; Torre, Luigi

    2017-05-01

    The aim of this work was to evaluate the stress distribution inside endodontically treated teeth restored with different posts (glass fibre, carbon fibre and steel posts) under different loading conditions by using a 3D-finite element analysis. The effect of masticatory and impact forces on teeth with different degrees of bone loss was analysed. The model consists of: dentine, post, cement, gutta-percha, core and crown. Four simulations were conducted with two static forces (170N horizontal and 100N oblique) and two sections constrained: 1mm (alveolar bone position in a normal periodontium) and 6mm (middle of root) below the crown. Von Mises and the principal stresses were evaluated and analysed with a 3-way ANOVA and Tukey test (α=0.05) and the effect of fibre percentage analysed. Significant differences were found among the stress values for all conditions (p<0.05). Impact load was always responsible for the most critical situation especially when the bone loss was more evident. The system with steel posts showed the highest principal stresses at the post-cement interface with horizontal load and top constraints (compressive stress of 121MPa and tensile stress of 115MPa). The use of glass posts provides a more homogeneous behaviour of the system with lower stresses. Higher fibre percentages gave higher stress in the posts. Moreover, larger bone losses are responsible for important increase in stress. Thus, this work demonstrated that periodontal disease has an important role in the success of tooth restoration after endodontic therapy, influencing the choice of post material and depth.

  8. Patterning process exploration of metal 1 layer in 7nm node with 3D patterning flow simulations

    NASA Astrophysics Data System (ADS)

    Gao, Weimin; Ciofi, Ivan; Saad, Yves; Matagne, Philippe; Bachmann, Michael; Oulmane, Mohamed; Gillijns, Werner; Lucas, Kevin; Demmerle, Wolfgang; Schmoeller, Thomas

    2015-03-01

    In 7mn node (N7), the logic design requires the critical poly pitch (CPP) of 42-45nm and metal 1 (M1) pitch of 28- 32nm. Such high pattern density pushes the 193 immersion lithography solution toward its limit and also brings extremely complex patterning scenarios. The N7 M1 layer may require a self-aligned quadruple patterning (SAQP) with triple litho-etch (LE3) block process. Therefore, the whole patterning process flow requires multiple exposure+etch+deposition processes and each step introduces a particular impact on the pattern profiles and the topography. In this study, we have successfully integrated a simulation tool that enables emulation of the whole patterning flow with realistic process-dependent 3D profile and topology. We use this tool to study the patterning process variations of N7 M1 layer including the overlay control, the critical dimension uniformity (CDU) budget and the lithographic process window (PW). The resulting 3D pattern structure can be used to optimize the process flow, verify design rules, extract parasitics, and most importantly, simulate the electric field and identify hot spots for dielectric reliability. As an example application, we will report extractions of maximum electric field at M1 tipto- tip which is one of the most critical patterning locations and we will demonstrate the potential of this approach for investigating the impact of process variations on dielectric reliability. We will also present simulations of an alternative M1 patterning flow, with a single exposure block using extreme ultraviolet lithography (EUVL) and analyze its advantages compared to the LE3 block approach.

  9. High-temperature compatible 3D-integration processes for a vacuum-sealed CNT-based NEMS

    NASA Astrophysics Data System (ADS)

    Gueye, R.; Lee, S. W.; Akiyama, T.; Briand, D.; Roman, C.; Hierold, C.; de Rooij, N. F.

    2013-03-01

    A System-in-Package (SiP) concept for the 3D-integration of a Single Wall Carbon Nanotube (SWCNT) resonator with its CMOS driving electronics is presented. The key element of this advanced SiP is the monolithic 3D-integration of the MEMS with the CMOS electronics using Through Silicon Vias (TSVs) on an SOI wafer. This SiP includes: A glass cap vacuum-sealed to the main wafer using an eutectic bonding process: a low leak rate of 2.7 10-9 mbar•l/s was obtained; Platinum-TSVs, compatible with the SWCNT growth and release process; The TSVs were developed in a "via first" process and characterized at high-temperature — up to 850 °C. An ohmic contact between the Pt-metallization and the SOI silicon device layer was obtained; The driving CMOS electronic device is assembled to the MEMS using an Au stud bump technology. Keywords: System-in-Package (SiP), vacuum packaging, eutectic bonding, "via-first" TSVs, high-temperature platinum interconnects, ohmic contacts, Au-stud bumps assembly, CMOS electronics.

  10. Fully back-end TSV process by Cu electro-less plating for 3D smart sensor systems

    NASA Astrophysics Data System (ADS)

    Santagata, F.; Farriciello, C.; Fiorentino, G.; van Zeijl, H. W.; Silvestri, C.; Zhang, G. Q.; Sarro, P. M.

    2013-05-01

    A fully back-end process for high-aspect ratio through-silicon vias (TSVs) for 3D smart sensor systems is developed. Atomic layer deposition of TiN provides a highly conformal barrier as well as a seed layer for metal plating. Cu electro-less plating on the chemically activated TiN surfaces is applied to uniformly fill the TSVs in a significantly shorter time (2 h for 300 μm deep and 20 μm wide TSVs) than with Cu bottom-up electroplating (>20 h). The process is CMOS compatible and can be performed after the last metalization step, making it a fully back-end process (VIA-last approach). Wafers containing metal interconnections on both sides are in fact used as demonstrator. Four-terminal 3D Kelvin structures are fabricated and characterized. An average resistance value of 650 mΩ is measured for 300 μm deep TSVs with an aspect ratio of 15. The crosstalk between adjacent TSVs is also measured by means of S-parameters characterization on dedicated RF test structures. The closest TSVs (75 μm) show a reciprocal crosstalk of less than -20 dB at 30 GHz.

  11. Role of 3D force networks in linking grain scale to macroscale processes in sheared granular debris

    NASA Astrophysics Data System (ADS)

    Mair, K.; Jettestuen, E.; Abe, S.

    2013-12-01

    Active faults, landslides and subglacial tills contain accumulations of granular debris that evolve during sliding. The macroscopic motion in these environments is at least to some extent determined by processes operating in this sheared granular material. A valid question is how the local behavior at the individual granular contacts actually sums up to influence macroscopic sliding. Laboratory experiments and numerical modeling can potentially help elucidate this. Observations of jamming (stick) and unjamming (flow) as well as concentrated shear bands on the scale of 5-10 grains suggest that a simple continuum description may be insufficient to capture important elements of the behavior. We therefore seek a measure of the organization of the granular fabric and the 3D structure of the load bearing skeleton that effectively demonstrates how the individual grain interactions are manifested in the macroscopic sliding behavior we observe. Contact force networks are an expression of this. Here we investigate the structure and variability of the most connected system spanning force networks produced in 3D discrete element models of granular layers under shear. We use percolation measures to identify, characterize, compare and track the evolution of these strongly connected contact force networks. We show that specific topological measures used in describing the networks, such as number of contacts and coordination number, are sensitive to grain size distribution (and likely the grain shape) of the material as well as loading conditions. Hence, faults of different maturity would be expected to accommodate shear in different ways. Distinct changes in the topological characteristics i.e. the geometry of strong force networks with accumulated strain are directly correlated to fluctuations in macroscopic shearing resistance. This suggests that 3D force networks play an important bridging role between individual grain scale processes and macroscopic sliding behavior.

  12. Processing lidar waveform data for 3D visual assessment of forest environments

    NASA Astrophysics Data System (ADS)

    Pirotti, F.; Guarnieri, A.; Masiero, A.; Vettore, A.; Lingua, E.

    2014-06-01

    The objective of this report is to present and discuss a work-flow for extracting, from full-waveform (FW) lidar data, formats which are compatible with common information systems (GIS) and statistical software packages. Full-waveform, specifically for forestry, got attention from the scientific community because a more in-depth analysis can add valuable information for classification and modelling of related variables (e.g. biomass). In order to assess if this is feasible and if the results are useful, the end-user has to deal with raw datasets from lidar sensors. In this study case we propose and test a work-flow which is implemented through a selfdeveloped software integrating ad-hoc C++ libraries and a graphical user interface for an easier approach by end-users. This software allows the user to add raw FW data and produce several products which can successively be easily imported in GIS or statistical software. To achieve this we used some state-of-the-art methods which have been extensively reported in literature and we discuss results and future developments. Results show that this software package can effectively work as a tool for linking raw FW data with forest-related spatial processing by providing punctual information directly derived from the FW data or area-based aggregated information for a more generalized description of the earth surface.

  13. Effects of Kinetic Processes in Shaping Io's Global Plasma Environment: A 3D Hybrid Model

    NASA Technical Reports Server (NTRS)

    Lipatov, Alexander S.; Combi, Michael R.

    2006-01-01

    The global dynamics of the ionized and neutral gases in the environment of Io plays an important role in the interaction of Jupiter s corotating magnetospheric plasma with Io. Stationary simulations of this problem have already been done using the magnetohydrodynamics (MHD) and the electrodynamics approaches. One of the major results of recent simplified two-fluid model simulations [Saur, J., Neubauer, F.M., Strobel, D.F., Summers, M.E., 2002. J. Geophys. Res. 107 (SMP5), 1-18] was the production of the structure of the double-peak in the magnetic field signature of the Io flyby. These could not be explained before by standard MHD models. In this paper, we present a hybrid simulation for Io with kinetic ions and fluid electrons. This method employs a fluid description for electrons and neutrals, whereas for ions a particle approach is used. We also take into account charge-exchange and photoionization processes and solve self-consistently for electric and magnetic fields. Our model may provide a much more accurate description for the ion dynamics than previous approaches and allows us to account for the realistic anisotropic ion velocity distribution that cannot be done in fluid simulations with isotropic temperatures. The first results of such a simulation of the dynamics of ions in Io s environment are discussed in this paper. Comparison with the Galileo IO flyby results shows that this approach provides an accurate physical basis for the interaction and can therefore naturally reproduce all the observed salient features.

  14. Effects of Kinetic Processes in Shaping Io's Global Plasma Environment: A 3D Hybrid Model

    NASA Technical Reports Server (NTRS)

    Lipatov, Alexander S.; Combi, Michael R.

    2006-01-01

    The global dynamics of the ionized and neutral gases in the environment of Io plays an important role in the interaction of Jupiter s corotating magnetospheric plasma with Io. Stationary simulations of this problem have already been done using the magnetohydrodynamics (MHD) and the electrodynamics approaches. One of the major results of recent simplified two-fluid model simulations [Saur, J., Neubauer, F.M., Strobel, D.F., Summers, M.E., 2002. J. Geophys. Res. 107 (SMP5), 1-18] was the production of the structure of the double-peak in the magnetic field signature of the Io flyby. These could not be explained before by standard MHD models. In this paper, we present a hybrid simulation for Io with kinetic ions and fluid electrons. This method employs a fluid description for electrons and neutrals, whereas for ions a particle approach is used. We also take into account charge-exchange and photoionization processes and solve self-consistently for electric and magnetic fields. Our model may provide a much more accurate description for the ion dynamics than previous approaches and allows us to account for the realistic anisotropic ion velocity distribution that cannot be done in fluid simulations with isotropic temperatures. The first results of such a simulation of the dynamics of ions in Io s environment are discussed in this paper. Comparison with the Galileo IO flyby results shows that this approach provides an accurate physical basis for the interaction and can therefore naturally reproduce all the observed salient features.

  15. Jaw tissues segmentation in dental 3D CT images using fuzzy-connectedness and morphological processing.

    PubMed

    Lloréns, Roberto; Naranjo, Valery; López, Fernando; Alcañiz, Mariano

    2012-11-01

    The success of oral surgery is subject to accurate advanced planning. In order to properly plan for dental surgery or a suitable implant placement, it is necessary an accurate segmentation of the jaw tissues: the teeth, the cortical bone, the trabecular core and over all, the inferior alveolar nerve. This manuscript presents a new automatic method that is based on fuzzy connectedness object extraction and mathematical morphology processing. The method uses computed tomography data to extract different views of the jaw: a pseudo-orthopantomographic view to estimate the path of the nerve and cross-sectional views to segment the jaw tissues. The method has been tested in a groundtruth set consisting of more than 9000 cross-sections from 20 different patients and has been evaluated using four similarity indicators (the Jaccard index, Dice's coefficient, point-to-point and point-to-curve distances), achieving promising results in all of them (0.726±0.031, 0.840±0.019, 0.144±0.023 mm and 0.163±0.025 mm, respectively). The method has proven to be significantly automated and accurate, with errors around 5% (of the diameter of the nerve), and is easily integrable in current dental planning systems. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  16. Acquisition and Processing Protocols for Uav Images: 3d Modeling of Historical Buildings Using Photogrammetry

    NASA Astrophysics Data System (ADS)

    Murtiyoso, A.; Koehl, M.; Grussenmeyer, P.; Freville, T.

    2017-08-01

    Photogrammetry has seen an increase in the use of UAVs (Unmanned Aerial Vehicles) for both large and smaller scale cartography. The use of UAVs is also advantageous because it may be used for tasks requiring quick response, including in the case of the inspection and monitoring of buildings. The objective of the project is to study the acquisition and processing protocols which exist in the literature and to adapt them for UAV projects. This implies a study on the calibration of the sensors, flight planning, comparison of software solutions, data management, and analysis on the different products of a UAV project. Two historical buildings of the city of Strasbourg were used as case studies: a part of the Rohan Palace façade and the St-Pierre-le-Jeune Catholic church. In addition, a preliminary test was performed on the Josephine Pavilion. Two UAVs were used in this research; namely the Sensefly Albris and the DJI Phantom 3 Professional. The experiments have shown that the calibration parameters tend to be unstable for small sensors. Furthermore, the dense matching of images remains a particular problem to address in a close range photogrammetry project, more so in the presence of noise on the images. Data management in cases where the number of images is high is also very important. The UAV is nevertheless a suitable solution for the surveying and recording of historical buildings because it is able to take images from points of view which are normally inaccessible to classical terrestrial techniques.

  17. Effects of Kinetic Processes in Shaping Io's Global Plasma Environment: A 3D Hybrid Model

    NASA Technical Reports Server (NTRS)

    Lipatov, Alexander S.; Combi, Michael R.

    2004-01-01

    The global dynamics of the ionized and neutral components in the environment of Io plays an important role in the interaction of Jupiter's corotating magnetospheric plasma with Io. The stationary simulation of this problem was done in the MHD and the electrodynamics approaches. One of the main significant results from the simplified two-fluid model simulations was a production of the structure of the double-peak in the magnetic field signature of the I0 flyby that could not be explained by standard MHD models. In this paper, we develop a method of kinetic ion simulation. This method employs the fluid description for electrons and neutrals whereas for ions multilevel, drift-kinetic and particle, approaches are used. We also take into account charge-exchange and photoionization processes. Our model provides much more accurate description for ion dynamics and allows us to take into account the realistic anisotropic ion distribution that cannot be done in fluid simulations. The first results of such simulation of the dynamics of ions in the Io's environment are discussed in this paper.

  18. Post-training administration of a synthetic peptide ligand of the neural cell adhesion molecule, C3d, attenuates long-term expression of contextual fear conditioning.

    PubMed

    Cambon, K; Venero, C; Berezin, V; Bock, E; Sandi, C

    2003-01-01

    The neural cell adhesion molecule (NCAM) plays a key role in synaptic plasticity and memory formation. We have recently developed a synthetic peptide, termed C3d, which, through the binding to the first, N-terminal immunoglobulin-like (Ig) module in the extracellular portion of NCAM, has been shown to promote neurite outgrowth and synapse formation in vitro, and to interfere with passive avoidance memory in rats in vivo. In this study, we investigated whether the i.c.v. administration of C3d, either 5.5 h after or 2 days before training, could be effective to modulate the strength at which emotional memory for aversive situations is established into a long-term memory. The effects of the peptide were evaluated in adult male Wistar rats trained in the contextual fear conditioning task. The results indicated that C3d significantly reduced the subsequent long-term retention of the conditioned fear response when administered 5.5 h post-training, as indicated by retention tests performed 2-3 and 7 days post-training. However, this treatment failed to influence conditioning for this task when injected 2 days pre-training. Additional experiments showed that C3d did not influence the emotional or locomotor behaviour of the animals, when tested in the open field task. Furthermore, hippocampal levels of microtubule-associated protein 2 (MAP2), Synaptophysin and NCAM were found unchanged when evaluated by enzyme-linked immunosorbent assay in crude synaptosomal preparations 2 days after peptide i.c.v. injection. Therefore, post-training injection of this synthetic peptide was efficient to attenuate the strength at which memory for contextual fear conditioning was enduringly stored, whilst it did not affect the acquisition of new memories. In addition to further support the view that NCAM is critically involved in memory consolidation, the current findings suggest that the NCAM IgI module is a potential target for the development of therapeutic drugs capable to reduce the

  19. Multitemporal 3D data capturing and GIS analysis of fluvial processes and geomorphological changes with terrestrial laser scanning

    NASA Astrophysics Data System (ADS)

    Hämmerle, Martin; Forbriger, Markus; Höfle, Bernhard

    2013-04-01

    LiDAR is a state of the art method for directly capturing 3D geodata. A laser beam is emitted in a known direction. The time of flight of the laser pulse is recorded and transformed into the distance between sensor and scanned object. The result of the scanning process is a 3D laser point cloud densely covering the surveyed area. LiDAR is used in a vast variety of research fields. In this study, the focus is on the application of terrestrial laser scanning (TLS), the static and ground-based LiDAR operation, in a multitemporal analysis of fluvial geomorphology. Within the framework of two study projects in 2011/2012, two TLS surveys were carried out. The surveys covered a gravel bar of about 150 m × 25 m size in a side branch of the Neckar River near Heidelberg (49°28'36''N, 8°34'32''E) located in a nature reserve with natural river characteristics. The first survey was performed in November 2011, the second in June 2012. Due to seasonally changing water levels, the gravel bar was flooded and the morphology changed. For the field campaigns, a Riegl VZ-400 was available. Height control points and tie points for registration and georeferencing were obtained with a total station and GPS equipment. The first survey was done from 6 scan positions (77 million points) and the second from 5 positions (89 million points). The point spacing for each single scan was set to 3 mm at 10 m distance. Co-registration of the individual campaigns was done via an Iterative Closest Point algorithm. Thereafter, co-registration and fine georeferencing of both epochs was performed using manually selected tie points and least-squares adjustment. After filtering of vegetation in the 3D point cloud in the software OPALS, a digital terrain model (DTM) with 0.25 m by 0.25 m cell size was generated for each epoch. A difference raster model of the two DTMs for assessing the changes was derived excluding water surface areas using the signal amplitude recorded for each echo. From the mean

  20. In-process 3D laser measurement to control the fiber tape-laying for composite production

    NASA Astrophysics Data System (ADS)

    Schmitt, Robert; Mersmann, Christoph; Damm, Björn

    2010-05-01

    Metrology is the key to an economically feasible production of fiber-reinforced composites in the field of automated tape laying, applying a novel laser light-section sensor system (LLSS) to measure process quality and feed back the results to close control loops of the production system. The developed method derives 3D measurements from height profiles through an in-process surface scan by the integrated LLSS. Gaps, overlaps, misalignment and defects of the composite tapes are detected during their lay-up and consolidation by comparing the measurement results with a CAD/CAM model of the lay-up. The height profiles are processed with a novel algorithm based on a non-linear least-square fitting to a set of sigmoid functions to ensure sub-pixel accuracy.

  1. Effect of process parameters and crystal orientation on 3D anisotropic stress during CZ and FZ growth of silicon

    NASA Astrophysics Data System (ADS)

    Drikis, Ivars; Plate, Matiss; Sennikovs, Juris; Virbulis, Janis

    2017-09-01

    Simulations of 3D anisotropic stress are carried out in <100> and <111> oriented Si crystals grown by FZ and CZ processes for different diameters, growth rates and process stages. Temperature dependent elastic constants and thermal expansion coefficients are used in the FE simulations. The von Mises stress at the triple point line is 5-11% higher in <111> crystals compared to <100> crystals. The process parameters have a larger effect on the von Mises stress than the crystal orientation. Generally, the <111> crystal has a higher azimuthal variation of stress along the triple point line ( 8%) than the <100> crystal ( 2%). The presence of a crystal ridge increases the stress beside the ridge and decreases it on the ridge compared with the round crystal.

  2. Study of energy relaxation processes of the surface produced negative ions by using 3D3V-PIC simulation

    NASA Astrophysics Data System (ADS)

    Miyamoto, K.; Goto, I.; Nishioka, S.; Hatayama, A.; Hiratsuka, J.; Hanada, M.; Kojima, A.

    2017-08-01

    The energy relaxation processes of the surface produced H- ions due to the Coulomb collision and the charge exchange collision is verified by using 3D3V-PIC (three dimensions in real space and three dimensions in velocity space particle in cell) simulation. Under the present simulation condition (ne = 1.0 × 1018 m-3, TH+ = 0.25 eV, TH- = 1.5 eV (the initial temperature of the surface produced H- ion), nH/nH2 =0.5, nH = 9.4 × 1018 m-3, TH = 0.1 eV), it is indicated the Coulomb collision is dominant for the energy relaxation processes. Moreover, it is indicated from the emittance diagrams that the H- ion beam optics is improved by the energy relaxation processes.

  3. High-Throughput Microfluidic Platform for 3D Cultures of Mesenchymal Stem Cells, Towards Engineering Developmental Processes

    PubMed Central

    Occhetta, Paola; Centola, Matteo; Tonnarelli, Beatrice; Redaelli, Alberto; Martin, Ivan; Rasponi, Marco

    2015-01-01

    The development of in vitro models to screen the effect of different concentrations, combinations and temporal sequences of morpho-regulatory factors on stem/progenitor cells is crucial to investigate and possibly recapitulate developmental processes with adult cells. Here, we designed and validated a microfluidic platform to (i) allow cellular condensation, (ii) culture 3D micromasses of human bone marrow-derived mesenchymal stromal cells (hBM-MSCs) under continuous flow perfusion, and (ii) deliver defined concentrations of morphogens to specific culture units. Condensation of hBM-MSCs was obtained within 3 hours, generating micromasses in uniform sizes (56.2 ± 3.9 μm). As compared to traditional macromass pellet cultures, exposure to morphogens involved in the first phases of embryonic limb development (i.e. Wnt and FGF pathways) yielded more uniform cell response throughout the 3D structures of perfused micromasses (PMMs), and a 34-fold higher percentage of proliferating cells at day 7. The use of a logarithmic serial dilution generator allowed to identify an unexpected concentration of TGFβ3 (0.1 ng/ml) permissive to hBM-MSCs proliferation and inductive to chondrogenesis. This proof-of-principle study supports the described microfluidic system as a tool to investigate processes involved in mesenchymal progenitor cells differentiation, towards a ‘developmental engineering’ approach for skeletal tissue regeneration. PMID:25983217

  4. A novel structured dictionary for fast processing of 3D medical images, with application to computed tomography restoration and denoising

    NASA Astrophysics Data System (ADS)

    Karimi, Davood; Ward, Rabab K.

    2016-03-01

    Sparse representation of signals in learned overcomplete dictionaries has proven to be a powerful tool with applications in denoising, restoration, compression, reconstruction, and more. Recent research has shown that learned overcomplete dictionaries can lead to better results than analytical dictionaries such as wavelets in almost all image processing applications. However, a major disadvantage of these dictionaries is that their learning and usage is very computationally intensive. In particular, finding the sparse representation of a signal in these dictionaries requires solving an optimization problem that leads to very long computational times, especially in 3D image processing. Moreover, the sparse representation found by greedy algorithms is usually sub-optimal. In this paper, we propose a novel two-level dictionary structure that improves the performance and the speed of standard greedy sparse coding methods. The first (i.e., the top) level in our dictionary is a fixed orthonormal basis, whereas the second level includes the atoms that are learned from the training data. We explain how such a dictionary can be learned from the training data and how the sparse representation of a new signal in this dictionary can be computed. As an application, we use the proposed dictionary structure for removing the noise and artifacts in 3D computed tomography (CT) images. Our experiments with real CT images show that the proposed method achieves results that are comparable with standard dictionary-based methods while substantially reducing the computational time.

  5. Virtual forensic entomology: improving estimates of minimum post-mortem interval with 3D micro-computed tomography.

    PubMed

    Richards, Cameron S; Simonsen, Thomas J; Abel, Richard L; Hall, Martin J R; Schwyn, Daniel A; Wicklein, Martina

    2012-07-10

    We demonstrate how micro-computed tomography (micro-CT) can be a powerful tool for describing internal and external morphological changes in Calliphora vicina (Diptera: Calliphoridae) during metamorphosis. Pupae were sampled during the 1st, 2nd, 3rd and 4th quarter of development after the onset of pupariation at 23 °C, and placed directly into 80% ethanol for preservation. In order to find the optimal contrast, four batches of pupae were treated differently: batch one was stained in 0.5M aqueous iodine for 1 day; two for 7 days; three was tagged with a radiopaque dye; four was left unstained (control). Pupae stained for 7d in iodine resulted in the best contrast micro-CT scans. The scans were of sufficiently high spatial resolution (17.2 μm) to visualise the internal morphology of developing pharate adults at all four ages. A combination of external and internal morphological characters was shown to have the potential to estimate the age of blowfly pupae with a higher degree of accuracy and precision than using external morphological characters alone. Age specific developmental characters are described. The technique could be used as a measure to estimate a minimum post-mortem interval in cases of suspicious death where pupae are the oldest stages of insect evidence collected.

  6. B4 2 After, 3D Deformation Field From Matching Pre- To Post-Event Aerial LiDAR Point Clouds, The 2010 El Mayor-Cucapah M7.2 Earthquake Case

    NASA Astrophysics Data System (ADS)

    Hinojosa-Corona, A.; Nissen, E.; Limon-Tirado, J. F.; Arrowsmith, R.; Krishnan, A.; Saripalli, S.; Oskin, M. E.; Glennie, C. L.; Arregui, S. M.; Fletcher, J. M.; Teran, O. J.

    2013-05-01

    Aerial LiDAR surveys reconstruct with amazing fidelity the sinuosity of terrain relief. In this research we explore the 3D deformation field at the surface after a big earthquake (M7.2) by comparing pre- to post-event aerial LiDAR point clouds. The April 4 2010 earthquake produced a NW-SE surface rupture ~110km long with right-lateral normal slip up to 3m in magnitude over a very favorable target: scarcely vegetated and unaltered desert mountain range, sierras El Mayor and Cucapah, in northern Baja California, close to the US-México border. It is a plate boundary region between the Pacific and North American plates. The pre-event LiDAR with lower point density (0.013-0.033 pts m-2) required filtering and post-processing before comparing with the denser (9-18 pts m-2) more accurate post event dataset. The 3D surface displacement field was determined using an adaptation of the Iterative Closest Point (ICP) algorithm, implemented in the open source Point Cloud Library (PCL). The LiDAR datasets are first split into a grid of windows, and for each one, ICP iteratively converges on the rigid body transformation (comprising translations and rotations) that best aligns the pre- to post-event points. Perturbing the pre- and post-event point clouds independently with a synthetic right lateral inverse displacements of known magnitude along a proposed fault, ICP recovered the synthetically introduced translations. Windows with dimensions of 100-200m gave the best results for datasets with these densities. The simplified surface rupture photo interpreted and mapped in the field, delineates very well the vertical displacements patterns unveiled by ICP. The method revealed block rotations, some with clockwise and others counter clockwise direction along the simplified surface rupture. As ground truth, displacements from ICP have similar values as those measured in the field along the main rupture by Fletcher and collaborators. The vertical component was better estimated than the

  7. Characterization of immiscible fluid displacement processes with various capillary numbers and viscosity ratios in 3D natural sandstone

    NASA Astrophysics Data System (ADS)

    Tsuji, Takeshi; Jiang, Fei; Christensen, Kenneth T.

    2016-09-01

    To characterize the influence of reservoir conditions upon multiphase flow, we calculated fluid displacements (drainage processes) in 3D pore spaces of Berea sandstone using two-phase lattice Boltzmann (LB) simulations. The results of simulations under various conditions were used to classify the resulting two-phase flow behavior into three typical fluid displacement patterns on the diagram of capillary number (Ca) and viscosity ratio of the two fluids (M). In addition, the saturation of the nonwetting phase was calculated and mapped on the Ca-M diagram. We then characterized dynamic pore-filling events (i.e., Haines jumps) from the pressure variation of the nonwetting phase, and linked this behavior to the occurrence of capillary fingering. The results revealed the onset of capillary fingering in 3D natural rock at a higher Ca than in 2D homogeneous granular models, with the crossover region between typical displacement patterns broader than in the homogeneous granular model. Furthermore, saturation of the nonwetting phase mapped on the Ca-M diagram significantly depends on the rock models. These important differences between two-phase flow in 3D natural rock and in 2D homogeneous models could be due to the heterogeneity of pore geometry in the natural rock and differences in pore connectivity. By quantifying two-phase fluid behavior in the target reservoir rock under various conditions (e.g., saturation mapping on the Ca-M diagram), our approach could provide useful information for investigating suitable reservoir conditions for geo-fluid management (e.g., high CO2 saturation in CO2 storage).

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

    PubMed

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

    2016-01-01

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

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

    PubMed Central

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

    2016-01-01

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

  10. Droplet fragmentation: 3D imaging of a previously unidentified pore-scale process during multiphase flow in porous media

    PubMed Central

    Pak, Tannaz; Butler, Ian B.; Geiger, Sebastian; van Dijke, Marinus I. J.; Sorbie, Ken S.

    2015-01-01

    Using X-ray computed microtomography, we have visualized and quantified the in situ structure of a trapped nonwetting phase (oil) in a highly heterogeneous carbonate rock after injecting a wetting phase (brine) at low and high capillary numbers. We imaged the process of capillary desaturation in 3D and demonstrated its impacts on the trapped nonwetting phase cluster size distribution. We have identified a previously unidentified pore-scale event during capillary desaturation. This pore-scale event, described as droplet fragmentation of the nonwetting phase, occurs in larger pores. It increases volumetric production of the nonwetting phase after capillary trapping and enlarges the fluid−fluid interface, which can enhance mass transfer between the phases. Droplet fragmentation therefore has implications for a range of multiphase flow processes in natural and engineered porous media with complex heterogeneous pore spaces. PMID:25646491

  11. Diagnostic performance of magnetic resonance imaging and 3D endoanal ultrasound in detection, staging and assessment post treatment, in anal cancer.

    PubMed

    Reginelli, Alfonso; Granata, Vincenza; Fusco, Roberta; Granata, Francesco; Rega, Daniela; Roberto, Luca; Pellino, Gianluca; Rotondo, Antonio; Selvaggi, Francesco; Izzo, Francesco; Petrillo, Antonella; Grassi, Roberto

    2017-02-01

    We compared Magnetic Resonance Imaging (MRI) and 3D Endoanal Ultrasound (EAUS) imaging performance to confirm anal carcinoma and to monitor treatment response.58 patients with anal cancer were retrospectively enrolled. All patients underwent clinical examination, anoscopic examination; EAUS and contrast-enhanced MRI study before and after treatment. Four radiologists evaluated the presence of lesions, using a 4-point confidence scale, features of the lesion and nodes on EAUS images, T1-weighted (T1-W), T2-weighted (T2-W) and diffusion-weighted images (DWI) signal intensity (SI), the apparent diffusion coefficient (ADC) map for nodes and lesion, as well as enhancement pattern during dynamic MRI were assessed.All lesions were detected by EAUS while MRI detected 93.1% of anal cancer. MRI showed a good correlation with EAUS, anoscopy and clinical examination. The residual tissue not showed significant difference in EAUS assessment and T2-W SI in pre and post treatment. We found significant difference in dynamic study, in SI of DWI, in ADC map and values among responder's patients in pre and post treatment. The neoplastic nodes were hypoecoic on EAUS, with hyperintense signal on T2-W sequences and hypointense signal on T1-W. The neoplastic nodes showed SI on DWI sequences and ADC value similar to anal cancer. We found significant difference in nodes status in pre and post therapy on DWI data.3D EAUS and MRI are accurate techniques in anal cancer staging, although EAUS is more accurate than MRI for T1 stage. MRI allows correct detection of neoplastic nodes and can properly stratify patients into responders or non responders.

  12. 3D Geospatial Models for Visualization and Analysis of Groundwater Contamination at a Nuclear Materials Processing Facility

    NASA Astrophysics Data System (ADS)

    Stirewalt, G. L.; Shepherd, J. C.

    2003-12-01

    Analysis of hydrostratigraphy and uranium and nitrate contamination in groundwater at a former nuclear materials processing facility in Oklahoma were undertaken employing 3-dimensional (3D) geospatial modeling software. Models constructed played an important role in the regulatory decision process of the U.S. Nuclear Regulatory Commission (NRC) because they enabled visualization of temporal variations in contaminant concentrations and plume geometry. Three aquifer systems occur at the site, comprised of water-bearing fractured shales separated by indurated sandstone aquitards. The uppermost terrace groundwater system (TGWS) aquifer is composed of terrace and alluvial deposits and a basal shale. The shallow groundwater system (SGWS) aquifer is made up of three shale units and two sandstones. It is separated from the overlying TGWS and underlying deep groundwater system (DGWS) aquifer by sandstone aquitards. Spills of nitric acid solutions containing uranium and radioactive decay products around the main processing building (MPB), leakage from storage ponds west of the MPB, and leaching of radioactive materials from discarded equipment and waste containers contaminated both the TGWS and SGWS aquifers during facility operation between 1970 and 1993. Constructing 3D geospatial property models for analysis of groundwater contamination at the site involved use of EarthVision (EV), a 3D geospatial modeling software developed by Dynamic Graphics, Inc. of Alameda, CA. A viable 3D geohydrologic framework model was initially constructed so property data could be spatially located relative to subsurface geohydrologic units. The framework model contained three hydrostratigraphic zones equivalent to the TGWS, SGWS, and DGWS aquifers in which groundwater samples were collected, separated by two sandstone aquitards. Groundwater data collected in the three aquifer systems since 1991 indicated high concentrations of uranium (>10,000 micrograms/liter) and nitrate (> 500 milligrams

  13. VHDL token-based performance modeling for 2D and 3D infrared search and track processing

    NASA Astrophysics Data System (ADS)

    Pauer, Eric K.; Pettigrew, Mark N.; Myers, Cory S.; Madisetti, Vijay K.

    1998-10-01

    This study develops and evaluates a new VHDL-based performance modeling capability for multiprocessor systems. The framework for this methodology involved modeling the following system aspects: processor characterization, and data set size. Initially, all aspects are specified at an abstract level, and eventually become specified at a detailed level through the process of verification and refinement of design assumptions. Processor characterization involves modeling the processor's speed, instruction set, and memory hierarchy. Task modeling is concerned with the execution time and instruction mix of software tasks within the systems Network characterization models bus protocols, topology, and bandwidths. Data set size refers to how much data is represented by the tokens used in the models. In this study, we applied and evaluated this methodology using both 2D and 3D IR search and track (IRST) algorithms. Two different candidate processors were investigated: IBM PowerPC 604 and Texas Instruments TMS320C80. For the 2D IRST algorithm, the abstract and detailed performance modeling results were obtained for both processors using partitioned data and pipelined algorithmic approaches. For the 3D IRST algorithm, abstract performance models for pipelined and parallelized implementations on the PowerPC were developed. These models examined the feasibility of the implementations, the potential risk areas, and laid the groundwork for detailed performance modeling.

  14. Evaluation of a combined pre-processing and H.264-compression scheme for 3D integral images

    NASA Astrophysics Data System (ADS)

    Olsson, Roger; Sjöström, Mårten; Xu, Youzhi

    2007-01-01

    To provide sufficient 3D-depth fidelity, integral imaging (II) requires an increase in spatial resolution of several orders of magnitude from today's 2D images. We have recently proposed a pre-processing and compression scheme for still II-frames based on forming a pseudo video sequence (PVS) from sub images (SI), which is later coded using the H.264/MPEG-4 AVC video coding standard. The scheme has shown good performance on a set of reference images. In this paper we first investigate and present how five different ways to select the SIs when forming the PVS affect the schemes compression efficiency. We also study how the II-frame structure relates to the performance of a PVS coding scheme. Finally we examine the nature of the coding artifacts which are specific to the evaluated PVS-schemes. We can conclude that for all except the most complex reference image, all evaluated SI selection orders significantly outperforms JPEG 2000 where compression ratios of up to 342:1, while still keeping PSNR > 30 dB, is achieved. We can also confirm that when selecting PVS-scheme, the scheme which results in a higher PVS-picture resolution should be preferred to maximize compression efficiency. Our study of the coded II-frames also indicates that the SI-based PVS, contrary to other PVS schemes, tends to distribute its coding artifacts more homogenously over all 3D-scene depths.

  15. Single, aligned carbon nanotubes in 3D nanoscale architectures enabled by top-down and bottom-up manufacturable processes

    NASA Astrophysics Data System (ADS)

    Kaul, Anupama B.; Megerian, Krikor G.; von Allmen, Paul; Baron, Richard L.

    2009-02-01

    We have developed manufacturable approaches for forming single, vertically aligned carbon nanotubes, where the tubes are centered precisely, and placed within a few hundred nm of 1-1.5 µm deep trenches. These wafer-scale approaches were enabled by using chemically amplified resists and high density, low pressure plasma etching techniques to form the 3D nanoscale architectures. The tube growth was performed using dc plasma-enhanced chemical vapor deposition (PECVD), and the materials used in the pre-fabricated 3D architectures were chemically and structurally compatible with the high temperature (700 °C) PECVD synthesis of our tubes, in an ammonia and acetylene ambient. Such scalable, high throughput top-down fabrication processes, when integrated with the bottom-up tube synthesis techniques, should accelerate the development of plasma grown tubes for a wide variety of applications in electronics, such as nanoelectromechanical systems, interconnects, field emitters and sensors. Tube characteristics were also engineered to some extent, by adjusting the Ni catalyst thickness, as well as the pressure and plasma power during growth.

  16. Single, aligned carbon nanotubes in 3D nanoscale architectures enabled by top-down and bottom-up manufacturable processes.

    PubMed

    Kaul, Anupama B; Megerian, Krikor G; von Allmen, Paul; Baron, Richard L

    2009-02-18

    We have developed manufacturable approaches for forming single, vertically aligned carbon nanotubes, where the tubes are centered precisely, and placed within a few hundred nm of 1-1.5 microm deep trenches. These wafer-scale approaches were enabled by using chemically amplified resists and high density, low pressure plasma etching techniques to form the 3D nanoscale architectures. The tube growth was performed using dc plasma-enhanced chemical vapor deposition (PECVD), and the materials used in the pre-fabricated 3D architectures were chemically and structurally compatible with the high temperature (700 degrees C) PECVD synthesis of our tubes, in an ammonia and acetylene ambient. Such scalable, high throughput top-down fabrication processes, when integrated with the bottom-up tube synthesis techniques, should accelerate the development of plasma grown tubes for a wide variety of applications in electronics, such as nanoelectromechanical systems, interconnects, field emitters and sensors. Tube characteristics were also engineered to some extent, by adjusting the Ni catalyst thickness, as well as the pressure and plasma power during growth.

  17. Improving the process of geological mapping in sedimentary terrain by using high-resolution topography in 3D environments

    NASA Astrophysics Data System (ADS)

    Chan, Yu-Chang; Shih, Nai-Cih; Chiu, Chia-Hung; Hsieh, Yu-Chung

    2017-04-01

    Traditional geologic maps were basically produced by field geologists through direct field investigations and interpretations from 2D topographic maps. However, the quality of traditional geologic maps was knowingly compromised by field conditions, particularly, when the mapping area is largely inaccessible or covered by heavy forest canopies. Recent advancement in airborne LiDAR technology can virtually remove trees or buildings, thus, providing a useful high-resolution topographic data set for the bare ground surface. The high-resolution topography still needs to be interpreted in terms of geology, and fundamental questions regarding how to apply the high-resolution topography remain to be answered for improving the process and quality of geological mapping. In this study, we aim to test the quality and reliability of high-resolution geologic maps produced by recently developed methods by an example from the fold-and-thrust belt in northern Taiwan. We performed the geological mapping by applying the LiDAR-derived DEM, self-developed Python program tools and many layers of relevant information at interactive 3D environments on a computer. Our mapping results indicate that the proposed mapping methods will significantly raise the quality and consistency of the geologic maps. Our study also shows that in order to gain consistent mapping results, future high-resolution geologic maps should be produced in 3D environments based on existing geologic maps and a few field checks for verification.

  18. 3D micro-CT analysis of void formations and push-out bonding strength of resin cements used for fiber post cementation.

    PubMed

    Uzun, İsmail Hakkı; Malkoç, Meral Arslan; Keleş, Ali; Öğreten, Ayşe Tuba

    2016-04-01

    To investigate the void parameters within the resin cements used for fiber post cementation by micro-CT (µCT) and regional push-out bonding strength. Twenty-one, single and round shaped roots were enlarged with a low-speed drill following by endodontic treatment. The roots were divided into three groups (n=7) and fiber posts were cemented with Maxcem Elite, Multilink N and Superbond C&B resin cements. Specimens were scanned using µCT scanner at resolution of 13.7 µm. The number, area, and volume of voids between dentin and post were evaluated. A method of analysis based on the post segmentation was used, and coronal, middle and apical thirds considered separately. After the µCT analysis, roots were embedded in epoxy resin and sectioned into 2 mm thick slices (63 sections in total). Push-out testing was performed with universal testing device at 0.5 mm/min cross-head speed. Data were analyzed with Kruskal-Wallis and Mann-Whitney U tests (α=.05). Overall, significant differences between the resin cements and the post level were observed in the void number, area, and volume (P<.05). Super-Bond C&B showed the most void formation (44.86 ± 22.71). Multilink N showed the least void surface (3.51 ± 2.24 mm(2)) and volume (0.01 ± 0.01 mm(3)). Regional push-out bond strength of the cements was not different (P>.05). µCT proved to be a powerful non-destructive 3D analysis tool for visualizing the void parameters. Multilink N had the lowest void parameters. When efficiency of all cements was evaluated, direct relationship between the post region and push-out bonding strength was not observed.

  19. 3D micro-CT analysis of void formations and push-out bonding strength of resin cements used for fiber post cementation

    PubMed Central

    2016-01-01

    PURPOSE To investigate the void parameters within the resin cements used for fiber post cementation by micro-CT (µCT) and regional push-out bonding strength. MATERIALS AND METHODS Twenty-one, single and round shaped roots were enlarged with a low-speed drill following by endodontic treatment. The roots were divided into three groups (n=7) and fiber posts were cemented with Maxcem Elite, Multilink N and Superbond C&B resin cements. Specimens were scanned using µCT scanner at resolution of 13.7 µm. The number, area, and volume of voids between dentin and post were evaluated. A method of analysis based on the post segmentation was used, and coronal, middle and apical thirds considered separately. After the µCT analysis, roots were embedded in epoxy resin and sectioned into 2 mm thick slices (63 sections in total). Push-out testing was performed with universal testing device at 0.5 mm/min cross-head speed. Data were analyzed with Kruskal–Wallis and Mann–Whitney U tests (α=.05). RESULTS Overall, significant differences between the resin cements and the post level were observed in the void number, area, and volume (P<.05). Super-Bond C&B showed the most void formation (44.86 ± 22.71). Multilink N showed the least void surface (3.51 ± 2.24 mm2) and volume (0.01 ± 0.01 mm3). Regional push-out bond strength of the cements was not different (P>.05). CONCLUSION µCT proved to be a powerful non-destructive 3D analysis tool for visualizing the void parameters. Multilink N had the lowest void parameters. When efficiency of all cements was evaluated, direct relationship between the post region and push-out bonding strength was not observed. PMID:27141253

  20. Online process monitoring at quasi-simultaneous laser transmission welding using a 3D-scanner with integrated pyrometer

    NASA Astrophysics Data System (ADS)

    Schmailzl, A.; Steger, S.; Dostalek, M.; Hierl, S.

    2016-03-01

    Quasi-simultaneous laser transmission welding is a well-known joining technique for thermoplastics and mainly used in the automotive as well as in the medical industry. For process control usually the so called set-path monitoring is used, where the weld is specified as "good" if the irradiation time is inside a defined confidence interval. However, the detection of small-sized gaps or thermal damaged zones is not possible with this technique. The analyzation of the weld seam temperature during welding offers the possibility to overcome this problem. In this approach a 3D-scanner is used instead of a scanner with flat-field optic. By using a pyrometer in combination with a 3D-scanner no color-corrected optic is needed in order to provide that laser- and detection-spot are concentric. Experimental studies on polyethylene T-joints have shown that the quality of the signal is adequate, despite the use of an optical setup with a long working distance and a small optical aperture. The effects on temperature are studied for defects like a gap in the joining zone. Therefore a notch was milled into the absorbent polymer. In case of producing housings for electronic parts the effect of an electrical wire between the joining partners is also investigated. Both defects can be identified by a local temperature deviation even at a feed rate of four meters per second. Furthermore a strategy for signal-processing is demonstrated. By this, remaining defects can be identified. Consequently an online detection of local defects is possible, which makes a dynamic process control feasible.

  1. A novel 3D-layered electrochemical-thermal coupled model strategy for the nail-penetration process simulation

    NASA Astrophysics Data System (ADS)

    Liang, Guozhou; Zhang, Yiming; Han, Qi; Liu, Zhaoping; Jiang, Zhen; Tian, Shuang

    2017-02-01

    The safety is one of the persisting concerns related with Lithium-ion (Li-ion) batteries, among which the internal short-circuit is the most dangerous abusive situation and has always been the root cause for several catastrophic accidents in recent years. In this work, a 3D-layered electrochemical-thermal coupled model is employed to investigate the nail-penetration process in a Li-ion cell. The model is based on multilayer construction of a cell, and an effective strategy to evaluate the short-circuit area equivalent resistance (i.e. the equivalent resistance of short-circuit area that is caused by nail-penetration) during the penetration process is proposed. The developed model is proved to have capability of estimating the thermal runaway time, as well as the temperature distribution during nail-penetration process. It is also found that the active material loss during the nail-penetration process can be reconstructed by utilizing the developed model, which could provide understandings about the side reactions inside the cell during the nail-penetration process. The present study provides some insights about the nail-penetration process, and can be treated as a useful tool that helps the design of Li-ion cells for improving safety.

  2. 3-D Seismic Interpretation

    NASA Astrophysics Data System (ADS)

    Moore, Gregory F.

    2009-05-01

    This volume is a brief introduction aimed at those who wish to gain a basic and relatively quick understanding of the interpretation of three-dimensional (3-D) seismic reflection data. The book is well written, clearly illustrated, and easy to follow. Enough elementary mathematics are presented for a basic understanding of seismic methods, but more complex mathematical derivations are avoided. References are listed for readers interested in more advanced explanations. After a brief introduction, the book logically begins with a succinct chapter on modern 3-D seismic data acquisition and processing. Standard 3-D acquisition methods are presented, and an appendix expands on more recent acquisition techniques, such as multiple-azimuth and wide-azimuth acquisition. Although this chapter covers the basics of standard time processing quite well, there is only a single sentence about prestack depth imaging, and anisotropic processing is not mentioned at all, even though both techniques are now becoming standard.

  3. LatticeLibrary and BccFccRaycaster: Software for processing and viewing 3D data on optimal sampling lattices

    NASA Astrophysics Data System (ADS)

    Linnér, Elisabeth Schold; Morén, Max; Smed, Karl-Oskar; Nysjö, Johan; Strand, Robin

    In this paper, we present LatticeLibrary, a C++ library for general processing of 2D and 3D images sampled on arbitrary lattices. The current implementation supports the Cartesian Cubic (CC), Body-Centered Cubic (BCC) and Face-Centered Cubic (FCC) lattices, and is designed to facilitate addition of other sampling lattices. We also introduce BccFccRaycaster, a plugin for the existing volume renderer Voreen, making it possible to view CC, BCC and FCC data, using different interpolation methods, with the same application. The plugin supports nearest neighbor and trilinear interpolation at interactive frame rates. These tools will enable further studies of the possible advantages of non-Cartesian lattices in a wide range of research areas.

  4. Guiding gate-etch process development using 3D surface reaction modeling for 7nm and beyond

    NASA Astrophysics Data System (ADS)

    Dunn, Derren; Sporre, John R.; Deshpande, Vaibhav; Oulmane, Mohamed; Gull, Ronald; Ventzek, Peter; Ranjan, Alok

    2017-03-01

    Increasingly, advanced process nodes such as 7nm (N7) are fundamentally 3D and require stringent control of critical dimensions over high aspect ratio features. Process integration in these nodes requires a deep understanding of complex physical mechanisms to control critical dimensions from lithography through final etch. Polysilicon gate etch processes are critical steps in several device architectures for advanced nodes that rely on self-aligned patterning approaches to gate definition. These processes are required to meet several key metrics: (a) vertical etch profiles over high aspect ratios; (b) clean gate sidewalls free of etch process residue; (c) minimal erosion of liner oxide films protecting key architectural elements such as fins; and (e) residue free corners at gate interfaces with critical device elements. In this study, we explore how hybrid modeling approaches can be used to model a multi-step finFET polysilicon gate etch process. Initial parts of the patterning process through hardmask assembly are modeled using process emulation. Important aspects of gate definition are then modeled using a particle Monte Carlo (PMC) feature scale model that incorporates surface chemical reactions.1 When necessary, species and energy flux inputs to the PMC model are derived from simulations of the etch chamber. The modeled polysilicon gate etch process consists of several steps including a hard mask breakthrough step (BT), main feature etch steps (ME), and over-etch steps (OE) that control gate profiles at the gate fin interface. An additional constraint on this etch flow is that fin spacer oxides are left intact after final profile tuning steps. A natural optimization required from these processes is to maximize vertical gate profiles while minimizing erosion of fin spacer films.2

  5. A study of internal structure in components made by additive manufacturing process using 3 D X-ray tomography

    NASA Astrophysics Data System (ADS)

    Raguvarun, K.; Balasubramaniam, Krishnan; Rajagopal, Prabhu; Palanisamy, Suresh; Nagarajah, Romesh; Hoye, Nicholas; Curiri, Dominic; Kapoor, Ajay

    2015-03-01

    Additive manufacturing methods are gaining increasing popularity for rapidly and efficiently manufacturing parts and components in the industrial context, as well as for domestic applications. However, except when used for prototyping or rapid visualization of components, industries are concerned with the load carrying capacity and strength achievable by additive manufactured parts. In this paper, the wire-arc additive manufacturing (AM) process based on gas tungsten arc welding (GTAW) has been examined for the internal structure and constitution of components generated by the process. High-resolution 3D X-ray tomography is used to gain cut-views through wedge-shaped parts created using this GTAW additive manufacturing process with titanium alloy materials. In this work, two different control conditions for the GTAW process are considered. The studies reveal clusters of porosities, located in periodic spatial intervals along the sample cross-section. Such internal defects can have a detrimental effect on the strength of the resulting AM components, as shown in destructive testing studies. Closer examination of this phenomenon shows that defect clusters are preferentially located at GTAW traversal path intervals. These results highlight the strong need for enhanced control of process parameters in ensuring components with minimal defects and higher strength.

  6. A study of internal structure in components made by additive manufacturing process using 3 D X-ray tomography

    SciTech Connect

    Raguvarun, K. Balasubramaniam, Krishnan Rajagopal, Prabhu; Palanisamy, Suresh; Nagarajah, Romesh; Kapoor, Ajay; Hoye, Nicholas; Curiri, Dominic

    2015-03-31

    Additive manufacturing methods are gaining increasing popularity for rapidly and efficiently manufacturing parts and components in the industrial context, as well as for domestic applications. However, except when used for prototyping or rapid visualization of components, industries are concerned with the load carrying capacity and strength achievable by additive manufactured parts. In this paper, the wire-arc additive manufacturing (AM) process based on gas tungsten arc welding (GTAW) has been examined for the internal structure and constitution of components generated by the process. High-resolution 3D X-ray tomography is used to gain cut-views through wedge-shaped parts created using this GTAW additive manufacturing process with titanium alloy materials. In this work, two different control conditions for the GTAW process are considered. The studies reveal clusters of porosities, located in periodic spatial intervals along the sample cross-section. Such internal defects can have a detrimental effect on the strength of the resulting AM components, as shown in destructive testing studies. Closer examination of this phenomenon shows that defect clusters are preferentially located at GTAW traversal path intervals. These results highlight the strong need for enhanced control of process parameters in ensuring components with minimal defects and higher strength.

  7. MRO DKF Post-Processing Tool

    NASA Technical Reports Server (NTRS)

    Ayap, Shanti; Fisher, Forest; Gladden, Roy; Khanampompan, Teerapat

    2008-01-01

    This software tool saves time and reduces risk by automating two labor-intensive and error-prone post-processing steps required for every DKF [DSN (Deep Space Network) Keyword File] that MRO (Mars Reconnaissance Orbiter) produces, and is being extended to post-process the corresponding TSOE (Text Sequence Of Events) as well. The need for this post-processing step stems from limitations in the seq-gen modeling resulting in incorrect DKF generation that is then cleaned up in post-processing.

  8. Permafrost sub-grid heterogeneity of soil properties key for 3-D soil processes and future climate projections

    NASA Astrophysics Data System (ADS)

    Beer, Christian

    2016-08-01

    There are massive carbon stocks stored in permafrost-affected soils due to the 3-D soil movement process called cryoturbation. For a reliable projection of the past, recent and future Arctic carbon balance, and hence climate, a reliable concept for representing cryoturbation in a land surface model (LSM) is required. The basis of the underlying transport processes is pedon-scale heterogeneity of soil hydrological and thermal properties as well as insulating layers, such as snow and vegetation. Today we still lack a concept of how to reliably represent pedon-scale properties and processes in a LSM. One possibility could be a statistical approach. This perspective paper demonstrates the importance of sub-grid heterogeneity in permafrost soils as a pre-requisite to implement any lateral transport parametrization. Representing such heterogeneity at the sub-pixel size of a LSM is the next logical step of model advancements. As a result of a theoretical experiment, heterogeneity of thermal and hydrological soil properties alone lead to a remarkable initial sub-grid range of subsoil temperature of 2 deg C, and active-layer thickness of 150 cm in East Siberia. These results show the way forward in representing combined lateral and vertical transport of water and soil in LSMs.

  9. Manufacturing a Porous Structure According to the Process Parameters of Functional 3D Porous Polymer Printing Technology Based on a Chemical Blowing Agent

    NASA Astrophysics Data System (ADS)

    Yoo, C. J.; Shin, B. S.; Kang, B. S.; Yun, D. H.; You, D. B.; Hong, S. M.

    2017-09-01

    In this paper, we propose a new porous polymer printing technology based on CBA(chemical blowing agent), and describe the optimization process according to the process parameters. By mixing polypropylene (PP) and CBA, a hybrid CBA filament was manufactured; the diameter of the filament ranged between 1.60 mm and 1.75 mm. A porous polymer structure was manufactured based on the traditional fused deposition modelling (FDM) method. The process parameters of the three-dimensional (3D) porous polymer printing (PPP) process included nozzle temperature, printing speed, and CBA density. Porosity increase with an increase in nozzle temperature and CBA density. On the contrary, porosity increase with a decrease in the printing speed. For porous structures, it has excellent mechanical properties. We manufactured a simple shape in 3D using 3D PPP technology. In the future, we will study the excellent mechanical properties of 3D PPP technology and apply them to various safety fields.

  10. Image post-processing in dental practice.

    PubMed

    Gormez, Ozlem; Yilmaz, Hasan Huseyin

    2009-10-01

    Image post-processing of dental digital radiographs, a function which used commonly in dental practice is presented in this article. Digital radiography has been available in dentistry for more than 25 years and its use by dental practitioners is steadily increasing. Digital acquisition of radiographs enables computer-based image post-processing to enhance image quality and increase the accuracy of interpretation. Image post-processing applications can easily be practiced in dental office by a computer and image processing programs. In this article, image post-processing operations such as image restoration, image enhancement, image analysis, image synthesis, and image compression, and their diagnostic efficacy is described. In addition this article provides general dental practitioners with a broad overview of the benefits of the different image post-processing operations to help them understand the role of that the technology can play in their practices.

  11. Sensor fusion of 2D and 3D data for the processing of images of dental imprints

    NASA Astrophysics Data System (ADS)

    Methot, Jean-Francois; Mokhtari, Marielle; Laurendeau, Denis; Poussart, Denis

    1993-08-01

    This paper presents a computer vision system for the acquisition and processing of 3-D images of wax dental imprints. The ultimate goal of the system is to measure a set of 10 orthodontic parameters that will be fed to an expert system for automatic diagnosis of occlusion problems. An approach for the acquisition of range images of both sides of the imprint is presented. Range is obtained from a shape-from-absorption technique applied to a pair of grey-level images obtained at two different wavelengths. The accuracy of the range values is improved using sensor fusion between the initial range image and a reflectance image from the pair of grey-level images. The improved range image is segmented in order to find the interstices between teeth and, following further processing, the type of each tooth on the profile. Once each tooth has been identified, its accurate location on the imprint is found using a region- growing approach and its shape is reconstructed with third degree polynomial functions. The reconstructed shape will be later used by the system to find specific features that are needed to estimate the orthodontic parameters.

  12. Dimension-Controllable Microtube Arrays by Dynamic Holographic Processing as 3D Yeast Culture Scaffolds for Asymmetrical Growth Regulation.

    PubMed

    Ji, Shengyun; Yang, Liang; Hu, Yanlei; Ni, Jincheng; Du, Wenqiang; Li, Jiawen; Zhao, Gang; Wu, Dong; Chu, Jiaru

    2017-09-01

    Transparent microtubes can function as unique cell culture scaffolds, because the tubular 3D microenvironment they provide is very similar to the narrow space of capillaries in vivo. However, how to realize the fabrication of microtube-arrays with variable cross-section dynamically remains challenging. Here, a dynamic holographic processing method for producing high aspect ratio (≈20) microtubes with tunable outside diameter (6-16 µm) and inside diameter (1-10 µm) as yeast culture scaffolds is reported. A ring-structure Bessel beam is modulated from a typical Gaussian-distributed femtosecond laser beam by a spatial light modulator. By combining the axial scanning of the focused beam and the dynamic display of holograms, dimension-controllable microtube arrays (straight, conical, and drum-shape) are rapidly produced by two-photon polymerization. The outside and inside diameters, tube heights, and spatial arrangements are readily tuned by loading different computer-generated holograms and changing the processing parameters. The transparent microtube array as a nontrivial tool for capturing and culturing the budding yeasts reveals the significant effect of tube diameter on budding characteristics. In particular, the conical tube with the inside diameter varying from 5 to 10 µm has remarkable asymmetrical regulation on the growth trend of captured yeasts. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Multigrid mapping and box relaxation for simulation of the whole process of flow transition in 3-D boundary layers

    SciTech Connect

    Liu, C.; Liu, Z.

    1994-12-31

    A new multilevel technology was developed in this study which provides a successful numerical simulation for the whole process of flow transition in 3-D flat plate boundary layers, including linear growth, secondary instability, breakdown, and transition on a relatively coarse grid with low CPU cost. A fourth-order finite difference scheme on stretched and staggered grids, a fully implicit time-marching technique, a semi-coarsening multigrid based on the so-called approximate line-box relaxation, and a buffer domain for the outflow boundary conditions were all employed for high-order accuracy, good stability, and fast convergence. A new fine-coarse-fine grid mapping technique was developed to catch the large eddies and represent main roles of small eddies to keep the code running after the laminar flow breaks down. The computational results are in good agreement with linear stability theory, secondary instability theory, and some experiments. The computation also reproduced the K-type and C-type transition observed by laboratory experiments. The CPU cost for a typical case is around 2-9 CRAY-YMP hours.

  14. A workflow to process 3D+time microscopy images of developing organisms and reconstruct their cell lineage

    PubMed Central

    Faure, Emmanuel; Savy, Thierry; Rizzi, Barbara; Melani, Camilo; Stašová, Olga; Fabrèges, Dimitri; Špir, Róbert; Hammons, Mark; Čúnderlík, Róbert; Recher, Gaëlle; Lombardot, Benoît; Duloquin, Louise; Colin, Ingrid; Kollár, Jozef; Desnoulez, Sophie; Affaticati, Pierre; Maury, Benoît; Boyreau, Adeline; Nief, Jean-Yves; Calvat, Pascal; Vernier, Philippe; Frain, Monique; Lutfalla, Georges; Kergosien, Yannick; Suret, Pierre; Remešíková, Mariana; Doursat, René; Sarti, Alessandro; Mikula, Karol; Peyriéras, Nadine; Bourgine, Paul

    2016-01-01

    The quantitative and systematic analysis of embryonic cell dynamics from in vivo 3D+time image data sets is a major challenge at the forefront of developmental biology. Despite recent breakthroughs in the microscopy imaging of living systems, producing an accurate cell lineage tree for any developing organism remains a difficult task. We present here the BioEmergences workflow integrating all reconstruction steps from image acquisition and processing to the interactive visualization of reconstructed data. Original mathematical methods and algorithms underlie image filtering, nucleus centre detection, nucleus and membrane segmentation, and cell tracking. They are demonstrated on zebrafish, ascidian and sea urchin embryos with stained nuclei and membranes. Subsequent validation and annotations are carried out using Mov-IT, a custom-made graphical interface. Compared with eight other software tools, our workflow achieved the best lineage score. Delivered in standalone or web service mode, BioEmergences and Mov-IT offer a unique set of tools for in silico experimental embryology. PMID:26912388

  15. SU-E-T-61: A Practical Process for Fabricating Passive Scatter Proton Beam Modulation Compensation Filters Using 3D Printing

    SciTech Connect

    Zhao, T; Drzymala, R

    2015-06-15

    Purpose: The purpose of this project was to devise a practical fabrication process for passive scatter proton beam compensation filters (CF) that is competitive in time, cost and effort using 3D printing. Methods: DICOM compensator filter files for a proton beam were generated by our Eclipse (Varian, Inc.) treatment planning system. The compensator thickness specifications were extracted with in-house software written in Matlab (MathWorks, Inc.) code and written to a text file which could be read by the Rhinoceros 5, computer-aided design (CAD) package (Robert McNeel and Associates), which subsequently generated a smoothed model in a STereoLithographic also known as a Standard Tesselation Language file (STL). The model in the STL file was subsequently refined using Netfabb software and then converted to printing instructions using Cura. version 15.02.1. for our 3D printer. The Airwolf3D, model HD2x, fused filament fabrication (FFF) 3D printer (Airwolf3D.com) was used for our fabrication system with a print speed of 150mm per second. It can print in over 22 different plastic filament materials in a build volume of 11” x 8” x 12”. We choose ABS plastic to print the 3D model of the imprint for our CFs. Results: Prints of the CF could be performed at a print speed of 70mm per second. The time to print the 3D topology for the CF for the 14 cm diameter snout of our Mevion 250 proton accelerator was less than 3 hours. The printed model is intended to subsequently be used as a mold to imprint a molten wax cylindrical to form the compensation after cooling. The whole process should be performed for a typical 3 beam treatment plan within a day. Conclusion: Use of 3D printing is practical and can be used to print a 3D model of a CF within a few hours.

  16. Matrix density alters zyxin phosphorylation, which limits peripheral process formation and extension in endothelial cells invading 3D collagen matrices.

    PubMed

    Abbey, Colette A; Bayless, Kayla J

    2014-09-01

    This study was designed to determine the optimal conditions required for known pro-angiogenic stimuli to elicit successful endothelial sprouting responses. We used an established, quantifiable model of endothelial cell (EC) sprout initiation where ECs were tested for invasion in low (1 mg/mL) and high density (5 mg/mL) 3D collagen matrices. Sphingosine 1-phosphate (S1P) alone, or S1P combined with stromal derived factor-1α (SDF) and phorbol ester (TPA), elicited robust sprouting responses. The ability of these factors to stimulate sprouting was more effective in higher density collagen matrices. S1P stimulation resulted in a significant increase in invasion distance, and with the exception of treatment groups containing phorbol ester, invasion distance was longer in 1mg/mL compared to 5mg/mL collagen matrices. Closer examination of cell morphology revealed that increasing matrix density and supplementing with SDF and TPA enhanced the formation of multicellular structures more closely resembling capillaries. TPA enhanced the frequency and size of lumen formation and correlated with a robust increase in phosphorylation of p42/p44 Erk kinase, while S1P and SDF did not. Also, a higher number of significantly longer extended processes formed in 5mg/mL compared to 1mg/mL collagen matrices. Because collagen matrices at higher density have been reported to be stiffer, we tested for changes in the mechanosensitive protein, zyxin. Interestingly, zyxin phosphorylation levels inversely correlated with matrix density, while levels of total zyxin did not change significantly. Immunofluorescence and localization studies revealed that total zyxin was distributed evenly throughout invading structures, while phosphorylated zyxin was slightly more intense in extended peripheral processes. Silencing zyxin expression increased extended process length and number of processes, while increasing zyxin levels decreased extended process length. Altogether these data indicate that ECs

  17. Investigation of the adhesion properties of direct 3D printing of polymers and nanocomposites on textiles: Effect of FDM printing process parameters

    NASA Astrophysics Data System (ADS)

    Hashemi Sanatgar, Razieh; Campagne, Christine; Nierstrasz, Vincent

    2017-05-01

    In this paper, 3D printing as a novel printing process was considered for deposition of polymers on synthetic fabrics to introduce more flexible, resource-efficient and cost effective textile functionalization processes than conventional printing process like screen and inkjet printing. The aim is to develop an integrated or tailored production process for smart and functional textiles which avoid unnecessary use of water, energy, chemicals and minimize the waste to improve ecological footprint and productivity. Adhesion of polymer and nanocomposite layers which were 3D printed directly onto the textile fabrics using fused deposition modeling (FDM) technique was investigated. Different variables which may affect the adhesion properties including 3D printing process parameters, fabric type and filler type incorporated in polymer were considered. A rectangular shape according to the peeling standard was designed as 3D computer-aided design (CAD) to find out the effect of the different variables. The polymers were printed in different series of experimental design: nylon on polyamide 66 (PA66) fabrics, polylactic acid (PLA) on PA66 fabric, PLA on PLA fabric, and finally nanosize carbon black/PLA (CB/PLA) and multi-wall carbon nanotubes/PLA (CNT/PLA) nanocomposites on PLA fabrics. The adhesion forces were quantified using the innovative sample preparing method combining with the peeling standard method. Results showed that different variables of 3D printing process like extruder temperature, platform temperature and printing speed can have significant effect on adhesion force of polymers to fabrics while direct 3D printing. A model was proposed specifically for deposition of a commercial 3D printer Nylon filament on PA66 fabrics. In the following, among the printed polymers, PLA and its composites had high adhesion force to PLA fabrics.

  18. Post-trial anatomical frame alignment procedure for comparison of 3D joint angle measurement from magnetic/inertial measurement units and camera-based systems.

    PubMed

    Li, Qingguo; Zhang, Jun-Tian

    2014-11-01

    Magnetic and inertial measurement units (MIMUs) have been widely used as an alternative to traditional camera-based motion capture systems for 3D joint kinematics measurement. Since these sensors do not directly measure position, a pre-trial anatomical calibration, either with the assistance of a special protocol/apparatus or with another motion capture system is required to establish the transformation matrices between the local sensor frame and the anatomical frame (AF) of each body segment on which the sensors are attached. Because the axes of AFs are often used as the rotational axes in the joint angle calculation, any difference in the AF determination will cause discrepancies in the calculated joint angles. Therefore, a direct comparison of joint angles between MIMU systems and camera-based systems is less meaningful because the calculated joint angles contain a systemic error due to the differences in the AF determination. To solve this problem a new post-trial AF alignment procedure is proposed. By correcting the AF misalignments, the joint angle differences caused by the difference in AF determination are eliminated and the remaining discrepancies are mainly from the measurement accuracy of the systems themselves. Lower limb joint angles from 30 walking trials were used to validate the effectiveness of the proposed AF alignment procedure. This technique could serve as a new means for calibrating magnetic/inertial sensor-based motion capture systems and correcting for AF misalignment in scenarios where joint angles are compared directly.

  19. DYNA3D example problem manual

    SciTech Connect

    Lovejoy, S.C.; Whirley, R.G.

    1990-10-10

    This manual describes in detail the solution of ten example problems using the explicit nonlinear finite element code DYNA3D. The sample problems include solid, shell, and beam element types, and a variety of linear and nonlinear material models. For each example, there is first an engineering description of the physical problem to be studied. Next, the analytical techniques incorporated in the model are discussed and key features of DYNA3D are highlighted. INGRID commands used to generate the mesh are listed, and sample plots from the DYNA3D analysis are given. Finally, there is a description of the TAURUS post-processing commands used to generate the plots of the solution. This set of example problems is useful in verifying the installation of DYNA3D on a new computer system. In addition, these documented analyses illustrate the application of DYNA3D to a variety of engineering problems, and thus this manual should be helpful to new analysts getting started with DYNA3D. 7 refs., 56 figs., 9 tabs.

  20. Quantification of groundwater extraction-induced subsidence in the Mekong delta, Vietnam: 3D process-based numerical modeling

    NASA Astrophysics Data System (ADS)

    Minderhoud, Philip S. J.; Erkens, Gilles; Pham, Hung V.; Bui, Vuong T.; Kooi, Henk; Erban, Laura; Stouthamer, Esther

    2017-04-01

    The demand for groundwater in the Vietnamese Mekong delta has steadily risen over the past decades. As a result, hydraulic heads in the aquifers dropped on average 0.3-0.7 m/yr-1, potentially causing aquifer-system compaction. At present, the delta is experiencing subsidence rates up to several centimeters per year that outpace global sea level rise by an order of magnitude. However, the exact contribution of groundwater extraction to total subsidence in the delta has not been assessed yet. The objective of our study is to quantify the impact of 25 years of groundwater extraction on subsidence. We built a 3D numerical hydrogeological model comprising the multi-aquifer system of the entire Vietnamese Mekong delta. Groundwater dynamics in the aquifers was simulated over the past quarter-century based on the known extraction history and measured time series of hydraulic head. Subsequently, we calculated corresponding aquifer system compaction using a coupled land subsidence module, which includes a direct, elastic component and a secular, viscous component (i.e. creep). The hydrogeological model is able to reproduce the measured drawdowns in the multi-aquifer system of the past 25 years. Corresponding subsidence rates resulting from aquifer system compaction show a gradual increase over the past two decades to significant annual rates up to several centimeters. Groundwater extraction seems to be a dominant driver of subsidence in the delta, but does not explain the total measured subsidence. This process-based modeling approach can be used to quantify groundwater extraction-induced subsidence for coastal areas and at delta-scale worldwide.

  1. New 3D Bolton standards: coregistration of biplane x rays and 3D CT

    NASA Astrophysics Data System (ADS)

    Dean, David; Subramanyan, Krishna; Kim, Eun-Kyung

    1997-04-01

    The Bolton Standards 'normative' cohort (16 males, 16 females) have been invited back to the Bolton-Brush Growth Study Center for new biorthogonal plain film head x-rays and 3D (three dimensional) head CT-scans. A set of 29 3D landmarks were identified on both their biplane head film and 3D CT images. The current 3D CT image is then superimposed onto the landmarks collected from the current biplane head films. Three post-doctoral fellows have collected 37 3D landmarks from the Bolton Standards' 40 - 70 year old biplane head films. These films were captured annually during their growing period (ages 3 - 18). Using 29 of these landmarks the current 3D CT image is next warped (via thin plate spline) to landmarks taken from each participant's 18th year biplane head films, a process that is successively reiterated back to age 3. This process is demonstrated here for one of the Bolton Standards. The outer skull surfaces will be extracted from each warped 3D CT image and an average will be generated for each age/sex group. The resulting longitudinal series of average 'normative' boney skull surface images may be useful for craniofacial patient: diagnosis, treatment planning, stereotactic procedures, and outcomes assessment.

  2. SedWorks: A 3-D visualisation software package to help students link surface processes with depositional product

    NASA Astrophysics Data System (ADS)

    Jones, M. A.; Edwards, A.; Boulton, P.

    2010-12-01

    Helping students to develop a cognitive and intuitive feel for the different temporal and spatial scales of processes through which the rock record is assembled is a primary goal of geoscience teaching. SedWorks is a 3-D virtual geoscience world that integrates both quantitative modelling and field-based studies into one interactive package. The program aims to help students acquire scientific content, cultivate critical thinking skills, and hone their problem solving ability, while also providing them with the opportunity to practice the activities undertaken by professional earth scientists. SedWorks is built upon a game development platform used for constructing interactive 3-D applications. Initially the software has been developed for teaching the sedimentology component of a Geoscience degree and consists of a series of continents or land masses each possessing sedimentary environments which the students visit on virtual field trips. The students are able to interact with the software to collect virtual field data from both the modern environment and the stratigraphic record, and to formulate hypotheses based on their observations which they can test through virtual physical experimentation within the program. The program is modular in design in order to enhance its adaptability and to allow scientific content to be updated so that the knowledge and skills acquired are at the cutting edge. We will present an example module in which students undertake a virtual field study of a 2-km long stretch of a river to observe how sediment is transported and deposited. On entering the field area students are able to observe different bedforms in different parts of the river as they move up- and down-stream, as well as in and out of the river. As they explore, students discover ‘hot spots’ at which particular tools become available to them. This includes tools for measuring the physical parameters of the flow and sediment bed (e.g. velocity, depth, grain size, bed

  3. Messinian post-evaporitic paleogeography of the Po Plain-Adriatic region by 3D numerical modeling: implications for the Central Mediterranean desiccation during the MSC

    NASA Astrophysics Data System (ADS)

    Amadori, Chiara; Garcia-Castellanos, Daniel; Di Giulio, Andrea; Fantoni, Roberto; Ghielmi, Manlio; Sternai, Pietro; Toscani, Giovanni

    2017-04-01

    In the last decades the Messinian Salinity Crisis (MSC) has been the topic of a number of studies, in particular in onshore areas, as they offer a unique opportunity to analyze the controlling factors and the geological consequences of the estimated 1.5 km sea-level drop. During the MSC, the geometry of western and eastern sides of the Mediterranean basin was similar to the present day basin while, important changes took place in the central portion as a consequence of the (still ongoing) tectonic activity of the Apennine domain. Recent high-resolution 2D seismo-stratigraphic and 1D backstripping analysis by Eni E&P group described a step-wise sea-level lowering during evaporitic and post-evaporitic MSC phases in the Po Plain-Northern Adriatic foreland (PPAF), with a sea-level drop not exceeding 900 m. Thanks to a dense grid of 2D seismic profiles, integrated with ca. 200 well logs (confidential data, courtesy of ENI E&P), a 3D reconstruction of the entire northern PPAF basin geometry and the facies distribution during the Latest Messinian time has been carried out. In this study, we performed a 3D backstripping and lithospheric scale uplift calculations of the northern PPAF basin testing the 800-900m of sea-level draw down. The resulted restored Latest Messinian paleotopography (corresponding to the bottom Pliocene in the most of the study area) and related shoreline position, strongly fit with the recentmost continental/marine facies distribution maps. The latest Messinian morphology shows deep marine basins persisting during the entire MSC period, filled by clastic turbiditic sediments and a wide emerged area along the Southern Alps margin and Friulian-Venetian basin. A 3D reconstruction of the Latest Messinian surface shows peculiar river incisions along the Southern Alps margin; these V-shape canyons perfectly fit with the present day fluvial network, dating back the drainage origin at least at the Messinian acme. Moreover, if in a well-constrained marginal

  4. Nanostructured p-type CZTS thin films prepared by a facile solution process for 3D p-n junction solar cells.

    PubMed

    Park, Si-Nae; Sung, Shi-Joon; Sim, Jun-Hyoung; Yang, Kee-Jeong; Hwang, Dae-Kue; Kim, JunHo; Kim, Gee Yeong; Jo, William; Kim, Dae-Hwan; Kang, Jin-Kyu

    2015-07-07

    Nanoporous p-type semiconductor thin films prepared by a simple solution-based process with appropriate thermal treatment and three-dimensional (3D) p-n junction solar cells fabricated by depositing n-type semiconductor layers onto the nanoporous p-type thin films show considerable photovoltaic performance compared with conventional thin film p-n junction solar cells. Spin-coated p-type Cu2ZnSnS4 (CZTS) thin films prepared using metal chlorides and thiourea show unique nanoporous thin film morphology, which is composed of a cluster of CZTS nanograins of 50-500 nm, and the obvious 3D p-n junction structure is fabricated by the deposition of n-type CdS on the nanoporous CZTS thin films by chemical bath deposition. The photovoltaic properties of 3D p-n junction CZTS solar cells are predominantly affected by the scale of CZTS nanograins, which is easily controlled by the sulfurization temperature of CZTS precursor films. The scale of CZTS nanograins determines the minority carrier transportation within the 3D p-n junction between CZTS and CdS, which are closely related with the photocurrent of series resistance of 3D p-n junction solar cells. 3D p-n junction CZTS solar cells with nanograins below 100 nm show power conversion efficiency of 5.02%, which is comparable with conventional CZTS thin film solar cells.

  5. Strategy to Achieve Highly Porous/Biocompatible Macroscale Cell Blocks, Using a Collagen/Genipin-bioink and an Optimal 3D Printing Process.

    PubMed

    Kim, Yong Bok; Lee, Hyeongjin; Kim, Geun Hyung

    2016-11-30

    Recently, a three-dimensional (3D) bioprinting process for obtaining a cell-laden structure has been widely applied because of its ability to fabricate biomimetic complex structures embedded with and without cells. To successfully obtain a cell-laden porous block, the cell-delivering vehicle, bioink, is one of the significant factors. Until now, various biocompatible hydrogels (synthetic and natural biopolymers) have been utilized in the cell-printing process, but a bioink satisfying both biocompatibility and print-ability requirements to achieve a porous structure with reasonable mechanical strength has not been issued. Here, we propose a printing strategy with optimal conditions including a safe cross-linking procedure for obtaining a 3D porous cell block composed of a biocompatible collagen-bioink and genipin, a cross-linking agent. To obtain the optimal processing conditions, we modified the 3D printing machine and selected an optimal cross-linking condition (∼1 mM and 1 h) of genipin solution. To show the feasibility of the process, 3D pore-interconnected cell-laden constructs were manufactured using osteoblast-like cells (MG63) and human adipose stem cells (hASCs). Under these processing conditions, a macroscale 3D collagen-based cell block of 21 × 21 × 12 mm(3) and over 95% cell viability was obtained. In vitro biological testing of the cell-laden 3D porous structure showed that the embedded cells were sufficiently viable, and their proliferation was significantly higher; the cells also exhibited increased osteogenic activities compared to the conventional alginate-based bioink (control). The results indicated the fabrication process using the collagen-bioink would be an innovative platform to design highly biocompatible and mechanically stable cell blocks.

  6. 3D MR ventricle segmentation in pre-term infants with post-hemorrhagic ventricle dilatation (PHVD) using multi-phase geodesic level-sets.

    PubMed

    Qiu, Wu; Yuan, Jing; Rajchl, Martin; Kishimoto, Jessica; Chen, Yimin; de Ribaupierre, Sandrine; Chiu, Bernard; Fenster, Aaron

    2015-09-01

    Intraventricular hemorrhage (IVH) or bleed within the cerebral ventricles is a common condition among very low birth weight pre-term neonates. The prognosis for these patients is worsened should they develop progressive ventricular dilatation, i.e., post-hemorrhagic ventricle dilatation (PHVD), which occurs in 10-30% of IVH patients. Accurate measurement of ventricular volume would be valuable information and could be used to predict PHVD and determine whether that specific patient with ventricular dilatation requires treatment. While the monitoring of PHVD in infants is typically done by repeated transfontanell 2D ultrasound (US) and not MRI, once the patient's fontanels have closed around 12-18months of life, the follow-up patient scans are done by MRI. Manual segmentation of ventricles from MR images is still seen as a gold standard. However, it is extremely time- and labor-consuming, and it also has observer variability. This paper proposes an accurate multiphase geodesic level-set segmentation algorithm for the extraction of the cerebral ventricle system of pre-term PHVD neonates from 3D T1 weighted MR images. The proposed segmentation algorithm makes use of multi-region segmentation technique associated with spatial priors built from a multi-atlas registration scheme. The leave-one-out cross validation with 19 patients with mild enlargement of ventricles and 7 hydrocephalus patients shows that the proposed method is accurate, suggesting that the proposed approach could be potentially used for volumetric and morphological analysis of the ventricle system of IVH neonatal brains in clinical practice. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Probing primordial non-Gaussianity: the 3D Bispectrum of Ly-α forest and the redshifted 21-cm signal from the post reionization epoch

    SciTech Connect

    Sarkar, Tapomoy Guha; Hazra, Dhiraj Kumar E-mail: dhiraj@apctp.org

    2013-04-01

    We explore possibility of using the three dimensional bispectra of the Ly-α forest and the redshifted 21-cm signal from the post-reionization epoch to constrain primordial non-Gaussianity. Both these fields map out the large scale distribution of neutral hydrogen and maybe treated as tracers of the underlying dark matter field. We first present the general formalism for the auto and cross bispectrum of two arbitrary three dimensional biased tracers and then apply it to the specific case. We have modeled the 3D Ly-α transmitted flux field as a continuous tracer sampled along 1D skewers which corresponds to quasars sight lines. For the post reionization 21-cm signal we have used a linear bias model. We use a Fisher matrix analysis to present the first prediction for bounds on f{sub NL} and the other bias parameters using the three dimensional 21-cm bispectrum and other cross bispectra. The bounds on f{sub NL} depend on the survey volume, and the various observational noises. We have considered a BOSS like Ly-α survey where the average number density of quasars n-bar = 10{sup −3}Mpc{sup −2} and the spectra are measured at a 2-σ level. For the 21-cm signal we have considered a 4000 hrs observation with a futuristic SKA like radio array. We find that bounds on f{sub NL} obtained in our analysis (6 ≤ Δf{sub NL} ≤ 65) is competitive with CMBR and galaxy surveys and may prove to be an important alternative approach towards constraining primordial physics using future data sets. Further, we have presented a hierarchy of power of the bispectrum-estimators towards detecting the f{sub NL}. Given the quality of the data sets, one may use this method to optimally choose the right estimator and thereby provide better constraints on f{sub NL}. We also find that by combining the various cross-bispectrum estimators it is possible to constrain f{sub NL} at a level Δf{sub NL} ∼ 4.7. For the equilateral and orthogonal template we obtain Δf{sub NL}{sup equ} ∼ 17 and

  8. Non-linear Post Processing Image Enhancement

    NASA Technical Reports Server (NTRS)

    Hunt, Shawn; Lopez, Alex; Torres, Angel

    1997-01-01

    A non-linear filter for image post processing based on the feedforward Neural Network topology is presented. This study was undertaken to investigate the usefulness of "smart" filters in image post processing. The filter has shown to be useful in recovering high frequencies, such as those lost during the JPEG compression-decompression process. The filtered images have a higher signal to noise ratio, and a higher perceived image quality. Simulation studies comparing the proposed filter with the optimum mean square non-linear filter, showing examples of the high frequency recovery, and the statistical properties of the filter are given,

  9. Streamlined, Inexpensive 3D Printing of the Brain and Skull

    PubMed Central

    Cash, Sydney S.

    2015-01-01

    Neuroimaging technologies such as Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) collect three-dimensional data (3D) that is typically viewed on two-dimensional (2D) screens. Actual 3D models, however, allow interaction with real objects such as implantable electrode grids, potentially improving patient specific neurosurgical planning and personalized clinical education. Desktop 3D printers can now produce relatively inexpensive, good quality prints. We describe our process for reliably generating life-sized 3D brain prints from MRIs and 3D skull prints from CTs. We have integrated a standardized, primarily open-source process for 3D printing brains and skulls. We describe how to convert clinical neuroimaging Digital Imaging and Communications in Medicine (DICOM) images to stereolithography (STL) files, a common 3D object file format that can be sent to 3D printing services. We additionally share how to convert these STL files to machine instruction gcode files, for reliable in-house printing on desktop, open-source 3D printers. We have successfully printed over 19 patient brain hemispheres from 7 patients on two different open-source desktop 3D printers. Each brain hemisphere costs approximately $3–4 in consumable plastic filament as described, and the total process takes 14–17 hours, almost all of which is unsupervised (preprocessing = 4–6 hr; printing = 9–11 hr, post-processing = <30 min). Printing a matching portion of a skull costs $1–5 in consumable plastic filament and takes less than 14 hr, in total. We have developed a streamlined, cost-effective process for 3D printing brain and skull models. We surveyed healthcare providers and patients who confirmed that rapid-prototype patient specific 3D models may help interdisciplinary surgical planning and patient education. The methods we describe can be applied for other clinical, research, and educational purposes. PMID:26295459

  10. Streamlined, Inexpensive 3D Printing of the Brain and Skull.

    PubMed

    Naftulin, Jason S; Kimchi, Eyal Y; Cash, Sydney S

    2015-01-01

    Neuroimaging technologies such as Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) collect three-dimensional data (3D) that is typically viewed on two-dimensional (2D) screens. Actual 3D models, however, allow interaction with real objects such as implantable electrode grids, potentially improving patient specific neurosurgical planning and personalized clinical education. Desktop 3D printers can now produce relatively inexpensive, good quality prints. We describe our process for reliably generating life-sized 3D brain prints from MRIs and 3D skull prints from CTs. We have integrated a standardized, primarily open-source process for 3D printing brains and skulls. We describe how to convert clinical neuroimaging Digital Imaging and Communications in Medicine (DICOM) images to stereolithography (STL) files, a common 3D object file format that can be sent to 3D printing services. We additionally share how to convert these STL files to machine instruction gcode files, for reliable in-house printing on desktop, open-source 3D printers. We have successfully printed over 19 patient brain hemispheres from 7 patients on two different open-source desktop 3D printers. Each brain hemisphere costs approximately $3-4 in consumable plastic filament as described, and the total process takes 14-17 hours, almost all of which is unsupervised (preprocessing = 4-6 hr; printing = 9-11 hr, post-processing = <30 min). Printing a matching portion of a skull costs $1-5 in consumable plastic filament and takes less than 14 hr, in total. We have developed a streamlined, cost-effective process for 3D printing brain and skull models. We surveyed healthcare providers and patients who confirmed that rapid-prototype patient specific 3D models may help interdisciplinary surgical planning and patient education. The methods we describe can be applied for other clinical, research, and educational purposes.

  11. Precipitation Processes developed during ARM (1997), TOGA COARE (1992), GATE (1974), SCSMEX (1998), and KWAJEX (1999), Consistent 2D, semi-3D and 3D Cloud Resolving Model Simulations

    NASA Technical Reports Server (NTRS)

    Tao, Wei-Kuo; Hou, A.; Atlas, R.; Starr, D.; Sud, Y.

    2003-01-01

    Real clouds and cloud systems are inherently three-dimensional (3D). Because of the limitations in computer resources, however, most cloud-resolving models (CRMs) today are still two-dimensional (2D). A few 3D CRMs have been used to study the response of clouds to large-scale forcing. In these 3D simulations, the model domain was small, and the integration time was 6 hours. The major objectives of this paper are: (1) to assess the performance of the super-parameterization technique (i.e. is 2D or semi-3D CRM appropriate for the super-parameterization?); (2) calculate and examine the surface energy (especially radiation) and water budgets; (3) identify the differences and similarities in the organization and entrainment rates of convection between simulated 2D and 3D cloud systems.

  12. 3D modelling of non-linear visco-elasto-plastic crustal and lithospheric processes using LaMEM

    NASA Astrophysics Data System (ADS)

    Popov, Anton; Kaus, Boris

    2016-04-01

    LaMEM (Lithosphere and Mantle Evolution Model) is a three-dimensional thermo-mechanical numerical code to simulate crustal and lithospheric deformation. The code is based on a staggered finite difference (FDSTAG) discretization in space, which is a stable and very efficient technique to solve the (nearly) incompressible Stokes equations that does not suffer from spurious pressure modes or artificial compressibility (a typical feature of low-order finite element techniques). Higher order finite element methods are more accurate than FDSTAG methods under idealized test cases where the jump in viscosity is exactly aligned with the boundaries of the elements. Yet, geodynamically more realistic cases involve evolving subduction zones, nonlinear rheologies or localized plastic shear bands. In these cases, the viscosity pattern evolves spontaneously during a simulation or even during nonlinear iterations, and the advantages of higher order methods disappear and they all converge with approximately first order accuracy, similar to that of FDSTAG [1]. Yet, since FDSTAG methods have considerably less degrees of freedom than quadratic finite element methods, they require about an order of magnitude less memory for the same number of nodes in 3D which also implies that every matrix-vector multiplication is significantly faster. LaMEM is build on top of the PETSc library and uses the particle-in-cell technique to track material properties, history variables which makes it straightforward to incorporate effects like phase changes or chemistry. An internal free surface is present, together with (simple) erosion and sedimentation processes, and a number of methods are available to import complex geometries into the code (e.g, http://geomio.bitbucket.org). Customized Galerkin coupled geometric multigrid preconditioners are implemented which resulted in a good parallel scalability of the code (we have tested LaMEM on 458'752 cores [2]). Yet, the drawback of using FDSTAG

  13. Euro3D Science Conference

    NASA Astrophysics Data System (ADS)

    Walsh, J. R.

    2004-02-01

    The Euro3D RTN is an EU funded Research Training Network to foster the exploitation of 3D spectroscopy in Europe. 3D spectroscopy is a general term for spectroscopy of an area of the sky and derives its name from its two spatial + one spectral dimensions. There are an increasing number of instruments which use integral field devices to achieve spectroscopy of an area of the sky, either using lens arrays, optical fibres or image slicers, to pack spectra of multiple pixels on the sky (``spaxels'') onto a 2D detector. On account of the large volume of data and the special methods required to reduce and analyse 3D data, there are only a few centres of expertise and these are mostly involved with instrument developments. There is a perceived lack of expertise in 3D spectroscopy spread though the astronomical community and its use in the armoury of the observational astronomer is viewed as being highly specialised. For precisely this reason the Euro3D RTN was proposed to train young researchers in this area and develop user tools to widen the experience with this particular type of data in Europe. The Euro3D RTN is coordinated by Martin M. Roth (Astrophysikalisches Institut Potsdam) and has been running since July 2002. The first Euro3D science conference was held in Cambridge, UK from 22 to 23 May 2003. The main emphasis of the conference was, in keeping with the RTN, to expose the work of the young post-docs who are funded by the RTN. In addition the team members from the eleven European institutes involved in Euro3D also presented instrumental and observational developments. The conference was organized by Andy Bunker and held at the Institute of Astronomy. There were over thirty participants and 26 talks covered the whole range of application of 3D techniques. The science ranged from Galactic planetary nebulae and globular clusters to kinematics of nearby galaxies out to objects at high redshift. Several talks were devoted to reporting recent observations with newly

  14. Precipitation Processes Developed During ARM (1997), TOGA COARE (1992), GATE (1974), SCSMEX (1998), and KWAJEX (1999): Consistent 2D, Semi-3D and 3D Cloud Resolving Model Simulations

    NASA Technical Reports Server (NTRS)

    Tao, W-K.

    2003-01-01

    Real clouds and cloud systems are inherently three-dimensional (3D). Because of the limitations in computer resources, however, most cloud-resolving models (CRMs) today are still two-dimensional (2D). A few 3D CRMs have been used to study the response of clouds to large-scale forcing. In these 3D simulations, the model domain was small, and the integration time was 6 hours. Only recently have 3D experiments been performed for multi-day periods for tropical cloud systems with large horizontal domains at the National Center for Atmospheric Research (NACAR) and at NASA Goddard Space Flight Center . At Goddard, a 3D Goddard Cumulus Ensemble (GCE) model was used to simulate periods during TOGA COARE, SCSMEX and KWAJEX using 512 by 512 km domain (with 2 km resolution). The results indicate that surface precipitation and latent heating profiles are very similar between the 2D and 3D GCE model simulations. The reason for the strong similarity between the 2D and 3D CRM simulations is that the same observed large-scale advective tendencies of potential temperature, water vapor mixing ratio, and horizontal momentum were used as the main focusing in both the 2D and 3D models. Interestingly, the 2D and 3D versions of the CRM used at CSU showed significant differences in the rainfall and cloud statistics for three ARM cases. The major objectives of this paper are: (1) to assess the performance of the super-parameterization technique, (2) calculate and examine the surface energy (especially radiation) and water budgets, and (3) identify the differences and similarities in the organization and entrainment rates of convection between simulated 2D and 3D cloud systems.

  15. Novel 3D resist shaping process via e-beam lithography, with application for the formation of blased planar waveguide gratings and planar lenses on GaAs

    NASA Astrophysics Data System (ADS)

    Poli, Louis C.; Kondek, Christine A.; Novembre, Anthony E.; McLane, George F.

    1995-06-01

    saw tooth ramp. Successive features of increasing dose will build an increasingly thicker ramp of resist. Images are developed in ethanol, a first rinse in methanol and a final rinse in IPA/H2O. Planar lenses may also be attempted in this way by again doing a piece-wise construction of the shape, using a varying dose. The processed 3-D resist pattern is then transferred to the wafer by a magnetron RIE dry etch in an argon and boron trichloride atmosphere. Etching of the resist pattern and the wafer is performed so that protected areas of the wafer receive the least etch and the smallest relief. Etching selectivity may in part be set by choosing an appropriate mix in the etching atmosphere.

  16. T-HEMP3D user manual

    SciTech Connect

    Turner, D.

    1983-08-01

    The T-HEMP3D (Transportable HEMP3D) computer program is a derivative of the STEALTH three-dimensional thermodynamics code developed by Science Applications, Inc., under the direction of Ron Hofmann. STEALTH, in turn, is based entirely on the original HEMP3D code written at Lawrence Livermore National Laboratory. The primary advantage STEALTH has over its predecessors is that it was designed using modern structured design techniques, with rigorous programming standards enforced. This yields two benefits. First, the code is easily changeable; this is a necessity for a physics code used for research. The second benefit is that the code is easily transportable between different types of computers. The STEALTH program was transferred to LLNL under a cooperative development agreement. Changes were made primarily in three areas: material specification, coordinate generation, and the addition of sliding surface boundary conditions. The code was renamed T-HEMP3D to avoid confusion with other versions of STEALTH. This document summarizes the input to T-HEMP3D, as used at LLNL. It does not describe the physics simulated by the program, nor the numerical techniques employed. Furthermore, it does not describe the separate job steps of coordinate generation and post-processing, including graphical display of results. (WHK)

  17. 3D Spray Droplet Distributions in Sneezes

    NASA Astrophysics Data System (ADS)

    Techet, Alexandra; Scharfman, Barry; Bourouiba, Lydia

    2015-11-01

    3D spray droplet clouds generated during human sneezing are investigated using the Synthetic Aperture Feature Extraction (SAFE) method, which relies on light field imaging (LFI) and synthetic aperture (SA) refocusing computational photographic techniques. An array of nine high-speed cameras are used to image sneeze droplets and tracked the droplets in 3D space and time (3D + T). An additional high-speed camera is utilized to track the motion of the head during sneezing. In the SAFE method, the raw images recorded by each camera in the array are preprocessed and binarized, simplifying post processing after image refocusing and enabling the extraction of feature sizes and positions in 3D + T. These binary images are refocused using either additive or multiplicative methods, combined with thresholding. Sneeze droplet centroids, radii, distributions and trajectories are determined and compared with existing data. The reconstructed 3D droplet centroids and radii enable a more complete understanding of the physical extent and fluid dynamics of sneeze ejecta. These measurements are important for understanding the infectious disease transmission potential of sneezes in various indoor environments.

  18. A colour image reproduction framework for 3D colour printing

    NASA Astrophysics Data System (ADS)

    Xiao, Kaida; Sohiab, Ali; Sun, Pei-li; Yates, Julian M.; Li, Changjun; Wuerger, Sophie

    2016-10-01

    In this paper, the current technologies in full colour 3D printing technology were introduced. A framework of colour image reproduction process for 3D colour printing is proposed. A special focus was put on colour management for 3D printed objects. Two approaches, colorimetric colour reproduction and spectral based colour reproduction are proposed in order to faithfully reproduce colours in 3D objects. Two key studies, colour reproduction for soft tissue prostheses and colour uniformity correction across different orientations are described subsequently. Results are clear shown that applying proposed colour image reproduction framework, performance of colour reproduction can be significantly enhanced. With post colour corrections, a further improvement in colour process are achieved for 3D printed objects.

  19. 3D Seismic Reflection Imaging of Crustal Formation Processes on the East Pacific Rise, 9°57-42'N

    NASA Astrophysics Data System (ADS)

    Purdy, G. M.; Mutter, J. C.; Carbotte, S. M.; Canales, J. P.; Nedimovic, M. R.; Carton, H.; Newman, K. R.; Marjanovic, M.; Xu, M.; Aghaei, O.; Stowe, L. C.

    2008-12-01

    Between June 29th and August 19th 2008 the research vessel Marcus G Langseth carried out its first multi- streamer 3D seismic reflection imaging cruise, MGL08-12, by conducting a program research on the East Pacific Rise centered around 9°50'N. The primary goals were to create an accurate 3D seismic reflection image of the magmatic-hydrothermal system at this Integrated Study Site of the Ridge2000 program by imaging the structure of the axial magma chamber (AMC) lid and oceanic crust at a resolution, accuracy, and scale comparable to seafloor observations. The vessel acquired data with four, 6-kilometer solid streamers each comprising 468 active channels deployed with a total separation of 450 meters. Four gun strings with total volume of 3300 cubic inches in two groups fired alternately provide the source for a shot spacing of 37.5 meters. This configuration yields eight CMP lines for each of the sail lines that were spaced 300 m apart, and a static bin size of 6.25 m × 37.5 m in the along-track and across-track directions, respectively, providing a nominal fold of 40. The cruise accomplished the acquisition of ~3,782 km of sail line data. There are 111 across axis lines that required 10 repeated lines and 14 infills. Average feathering during the cruise was 0° ± 5° (one standard deviation), with maximum values of up to 11°. This means that 18% of the total cross axis acquisition was needed for reshoots and infilling. A 25% multiplier on planned lines for a 3D grid is probably a useful figure to use in cruise planning and is fairly standard in the seismic industry. Data quality meets or exceeds industry standards. 3D coverage was achieved in two areas. The larger comprises a set of 93 equally spaced lines forming the 3D grid between 9°57'N and 9°42'N. This grid is made up of lines from all of racetracks #1 and #2 and the northern lines of racetrack#3 and covers two principal hydrothermal vent areas in a continuous fashion. The second 3D area is comprised

  20. Europeana and 3D

    NASA Astrophysics Data System (ADS)

    Pletinckx, D.

    2011-09-01

    The current 3D hype creates a lot of interest in 3D. People go to 3D movies, but are we ready to use 3D in our homes, in our offices, in our communication? Are we ready to deliver real 3D to a general public and use interactive 3D in a meaningful way to enjoy, learn, communicate? The CARARE project is realising this for the moment in the domain of monuments and archaeology, so that real 3D of archaeological sites and European monuments will be available to the general public by 2012. There are several aspects to this endeavour. First of all is the technical aspect of flawlessly delivering 3D content over all platforms and operating systems, without installing software. We have currently a working solution in PDF, but HTML5 will probably be the future. Secondly, there is still little knowledge on how to create 3D learning objects, 3D tourist information or 3D scholarly communication. We are still in a prototype phase when it comes to integrate 3D objects in physical or virtual museums. Nevertheless, Europeana has a tremendous potential as a multi-facetted virtual museum. Finally, 3D has a large potential to act as a hub of information, linking to related 2D imagery, texts, video, sound. We describe how to create such rich, explorable 3D objects that can be used intuitively by the generic Europeana user and what metadata is needed to support the semantic linking.

  1. 3D Audio System

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Ames Research Center research into virtual reality led to the development of the Convolvotron, a high speed digital audio processing system that delivers three-dimensional sound over headphones. It consists of a two-card set designed for use with a personal computer. The Convolvotron's primary application is presentation of 3D audio signals over headphones. Four independent sound sources are filtered with large time-varying filters that compensate for motion. The perceived location of the sound remains constant. Possible applications are in air traffic control towers or airplane cockpits, hearing and perception research and virtual reality development.

  2. Twin Peaks - 3D

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The two hills in the distance, approximately one to two kilometers away, have been dubbed the 'Twin Peaks' and are of great interest to Pathfinder scientists as objects of future study. 3D glasses are necessary to identify surface detail. The white areas on the left hill, called the 'Ski Run' by scientists, may have been formed by hydrologic processes.

    The IMP is a stereo imaging system with color capability provided by 24 selectable filters -- twelve filters per 'eye.

    Click below to see the left and right views individually. [figure removed for brevity, see original site] Left [figure removed for brevity, see original site] Right

  3. Deformation and fatigue of tough 3D printed elastomer scaffolds processed by fused deposition modeling and continuous liquid interface production.

    PubMed

    Miller, Andrew T; Safranski, David L; Wood, Catherine; Guldberg, Robert E; Gall, Ken

    2017-07-01

    Polyurethane (PU) based elastomers continue to gain popularity in a variety of biomedical applications as compliant implant materials. In parallel, advancements in additive manufacturing continue to provide new opportunities for biomedical applications by enabling the creation of more complex architectures for tissue scaffolding and patient specific implants. The purpose of this study was to examine the effects of printed architecture on the monotonic and cyclic mechanical behavior of elastomeric PUs and to compare the structure-property relationship across two different printing approaches. We examined the tensile fatigue of notched specimens, 3D crosshatch scaffolds, and two 3D spherical pore architectures in a physically crosslinked polycarbonate urethane (PCU) printed via fused deposition modeling (FDM) as well as a photo-cured, chemically-crosslinked, elastomeric PU printed via continuous liquid interface production (CLIP). Both elastomers were relatively tolerant of 3D geometrical features as compared to stiffer synthetic implant materials such as PEEK and titanium. PCU and crosslinked PU samples with 3D porous structures demonstrated a reduced tensile failure stress as expected without a significant effect on tensile failure strain. PCU crosshatch samples demonstrated similar performance in strain-based tensile fatigue as solid controls; however, when plotted against stress amplitude and adjusted by porosity, it was clear that the architecture had an impact on performance. Square shaped notches or pores in crosslinked PU appeared to have a modest effect on strain-based tensile fatigue while circular shaped notches and pores had little impact relative to smooth samples. When plotted against stress amplitude, any differences in fatigue performance were small or not statistically significant for crosslinked PU samples. Despite the slight difference in local architecture and tolerances, crosslinked PU solid samples were found to perform on par with PCU solid

  4. 3-D GPS velocity field and its implications on the present-day post-orogenic deformation of the Western Alps and Pyrenees

    NASA Astrophysics Data System (ADS)

    Ninh Nguyen, Hai; Vernant, Philippe; Mazzotti, Stephane; Khazaradze, Giorgi; Asensio, Eva

    2016-09-01

    We present a new 3-D GPS velocity solution for 182 sites for the region encompassing the Western Alps, Pyrenees, and southern France. The velocity field is based on a Precise Point Positioning (PPP) solution, to which we apply a common-mode filter, defined by the 26 longest time series, in order to correct for network-wide biases (reference frame, unmodeled large-scale processes, etc.). We show that processing parameters, such as troposphere delay modeling, can lead to systematic velocity variations of 0.1-0.5 mm yr-1 affecting both accuracy and precision, especially for short (< 5 years) time series. A velocity convergence analysis shows that minimum time-series lengths of ˜ 3 and ˜ 5.5 years are required to reach a velocity stability of 0.5 mm yr-1 in the horizontal and vertical components, respectively. On average, horizontal residual velocities show a stability of ˜ 0.2 mm yr-1 in the Western Alps, Pyrenees, and southern France. The only significant horizontal strain rate signal is in the western Pyrenees with up to 4 × 10-9 yr-1 NNE-SSW extension, whereas no significant strain rates are detected in the Western Alps (< 1 × 10-9 yr-1). In contrast, we identify significant uplift rates up to 2 mm yr-1 in the Western Alps but not in the Pyrenees (0.1 ± 0.2 mm yr-1). A correlation between site elevations and fast uplift rates in the northern part of the Western Alps, in the region of the Würmian ice cap, suggests that part of this uplift is induced by postglacial rebound. The very slow uplift rates in the southern Western Alps and in the Pyrenees could be accounted for by erosion-induced rebound.

  5. Precipitation Processes developed during ARM (1997), TOGA COARE(1992), GATE(1 974), SCSMEX(1998) and KWAJEX(1999): Consistent 2D and 3D Cloud Resolving Model Simulations

    NASA Technical Reports Server (NTRS)

    Tao, W.-K.; Shie, C.-H.; Simpson, J.; Starr, D.; Johnson, D.; Sud, Y.

    2003-01-01

    Real clouds and clouds systems are inherently three dimensional (3D). Because of the limitations in computer resources, however, most cloud-resolving models (CRMs) today are still two-dimensional (2D). A few 3D CRMs have been used to study the response of clouds to large-scale forcing. In these 3D simulations, the model domain was small, and the integration time was 6 hours. Only recently have 3D experiments been performed for multi-day periods for tropical cloud system with large horizontal domains at the National Center for Atmospheric Research. The results indicate that surface precipitation and latent heating profiles are very similar between the 2D and 3D simulations of these same cases. The reason for the strong similarity between the 2D and 3D CRM simulations is that the observed large-scale advective tendencies of potential temperature, water vapor mixing ratio, and horizontal momentum were used as the main forcing in both the 2D and 3D models. Interestingly, the 2D and 3D versions of the CRM used in CSU and U.K. Met Office showed significant differences in the rainfall and cloud statistics for three ARM cases. The major objectives of this project are to calculate and axamine: (1)the surface energy and water budgets, (2) the precipitation processes in the convective and stratiform regions, (3) the cloud upward and downward mass fluxes in the convective and stratiform regions; (4) cloud characteristics such as size, updraft intensity and lifetime, and (5) the entrainment and detrainment rates associated with clouds and cloud systems that developed in TOGA COARE, GATE, SCSMEX, ARM and KWAJEX. Of special note is that the analyzed (model generated) data sets are all produced by the same current version of the GCE model, i.e. consistent model physics and configurations. Trajectory analyse and inert tracer calculation will be conducted to identify the differences and similarities in the organization of convection between simulated 2D and 3D cloud systems.

  6. High-throughput processes and structural characterization of single-nanotube based devices for 3D electronics

    NASA Astrophysics Data System (ADS)

    Kaul, A. B.; Megerian, K. G.; Baron, R. L.; Jennings, A. T.; Jang, D.; Greer, J. R.

    2009-05-01

    We have developed manufacturable approaches to form single, vertically aligned carbon nanotubes, where the tubes are centered precisely, and placed within a few hundred nm of 1-1.5 μm deep trenches. These wafer-scale approaches were enabled by chemically amplified resists and inductively coupled Cryo-etchers to form the 3D nanoscale architectures. The tube growth was performed using dc plasmaenhanced chemical vapor deposition (PECVD), and the materials used for the pre-fabricated 3D architectures were chemically and structurally compatible with the high temperature (700 °C) PECVD synthesis of our tubes, in an ammonia and acetylene ambient. The TEM analysis of our tubes revealed graphitic basal planes inclined to the central or fiber axis, with cone angles up to 30° for the particular growth conditions used. In addition, bending tests performed using a custom nanoindentor, suggest that the tubes are well adhered to the Si substrate. Tube characteristics were also engineered to some extent, by adjusting growth parameters, such as Ni catalyst thickness, pressure and plasma power during growth.

  7. High-Throughput Processes and Structural Characterization of Single-Nanotube Based Devices for 3D Electronics

    NASA Technical Reports Server (NTRS)

    Kaul, A. B.; Megerian, K. G.; Baron, R. L.; Jennings, A. T.; Jang, D.; Greer, J. R.

    2011-01-01

    We have developed manufacturable approaches to form single, vertically aligned carbon nanotubes, where the tubes are centered precisely, and placed within a few hundred nm of 1-1.5 micron deep trenches. These wafer-scale approaches were enabled by chemically amplified resists and inductively coupled Cryo-etchers to form the 3D nanoscale architectures. The tube growth was performed using dc plasmaenhanced chemical vapor deposition (PECVD), and the materials used for the pre-fabricated 3D architectures were chemically and structurally compatible with the high temperature (700 C) PECVD synthesis of our tubes, in an ammonia and acetylene ambient. The TEM analysis of our tubes revealed graphitic basal planes inclined to the central or fiber axis, with cone angles up to 30 deg. for the particular growth conditions used. In addition, bending tests performed using a custom nanoindentor, suggest that the tubes are well adhered to the Si substrate. Tube characteristics were also engineered to some extent, by adjusting growth parameters, such as Ni catalyst thickness, pressure and plasma power during growth.

  8. Analyzing Structure and Function of Vascularization in Engineered Bone Tissue by Video-Rate Intravital Microscopy and 3D Image Processing.

    PubMed

    Pang, Yonggang; Tsigkou, Olga; Spencer, Joel A; Lin, Charles P; Neville, Craig; Grottkau, Brian

    2015-10-01

    Vascularization is a key challenge in tissue engineering. Three-dimensional structure and microcirculation are two fundamental parameters for evaluating vascularization. Microscopic techniques with cellular level resolution, fast continuous observation, and robust 3D postimage processing are essential for evaluation, but have not been applied previously because of technical difficulties. In this study, we report novel video-rate confocal microscopy and 3D postimage processing techniques to accomplish this goal. In an immune-deficient mouse model, vascularized bone tissue was successfully engineered using human bone marrow mesenchymal stem cells (hMSCs) and human umbilical vein endothelial cells (HUVECs) in a poly (D,L-lactide-co-glycolide) (PLGA) scaffold. Video-rate (30 FPS) intravital confocal microscopy was applied in vitro and in vivo to visualize the vascular structure in the engineered bone and the microcirculation of the blood cells. Postimage processing was applied to perform 3D image reconstruction, by analyzing microvascular networks and calculating blood cell viscosity. The 3D volume reconstructed images show that the hMSCs served as pericytes stabilizing the microvascular network formed by HUVECs. Using orthogonal imaging reconstruction and transparency adjustment, both the vessel structure and blood cells within the vessel lumen were visualized. Network length, network intersections, and intersection densities were successfully computed using our custom-developed software. Viscosity analysis of the blood cells provided functional evaluation of the microcirculation. These results show that by 8 weeks, the blood vessels in peripheral areas function quite similarly to the host vessels. However, the viscosity drops about fourfold where it is only 0.8 mm away from the host. In summary, we developed novel techniques combining intravital microscopy and 3D image processing to analyze the vascularization in engineered bone. These techniques have broad

  9. Analyzing Structure and Function of Vascularization in Engineered Bone Tissue by Video-Rate Intravital Microscopy and 3D Image Processing

    PubMed Central

    Pang, Yonggang; Tsigkou, Olga; Spencer, Joel A.; Lin, Charles P.; Neville, Craig

    2015-01-01

    Vascularization is a key challenge in tissue engineering. Three-dimensional structure and microcirculation are two fundamental parameters for evaluating vascularization. Microscopic techniques with cellular level resolution, fast continuous observation, and robust 3D postimage processing are essential for evaluation, but have not been applied previously because of technical difficulties. In this study, we report novel video-rate confocal microscopy and 3D postimage processing techniques to accomplish this goal. In an immune-deficient mouse model, vascularized bone tissue was successfully engineered using human bone marrow mesenchymal stem cells (hMSCs) and human umbilical vein endothelial cells (HUVECs) in a poly (d,l-lactide-co-glycolide) (PLGA) scaffold. Video-rate (30 FPS) intravital confocal microscopy was applied in vitro and in vivo to visualize the vascular structure in the engineered bone and the microcirculation of the blood cells. Postimage processing was applied to perform 3D image reconstruction, by analyzing microvascular networks and calculating blood cell viscosity. The 3D volume reconstructed images show that the hMSCs served as pericytes stabilizing the microvascular network formed by HUVECs. Using orthogonal imaging reconstruction and transparency adjustment, both the vessel structure and blood cells within the vessel lumen were visualized. Network length, network intersections, and intersection densities were successfully computed using our custom-developed software. Viscosity analysis of the blood cells provided functional evaluation of the microcirculation. These results show that by 8 weeks, the blood vessels in peripheral areas function quite similarly to the host vessels. However, the viscosity drops about fourfold where it is only 0.8 mm away from the host. In summary, we developed novel techniques combining intravital microscopy and 3D image processing to analyze the vascularization in engineered bone. These techniques have broad

  10. Nanostructured p-type CZTS thin films prepared by a facile solution process for 3D p-n junction solar cells

    NASA Astrophysics Data System (ADS)

    Park, Si-Nae; Sung, Shi-Joon; Sim, Jun-Hyoung; Yang, Kee-Jeong; Hwang, Dae-Kue; Kim, Junho; Kim, Gee Yeong; Jo, William; Kim, Dae-Hwan; Kang, Jin-Kyu

    2015-06-01

    Nanoporous p-type semiconductor thin films prepared by a simple solution-based process with appropriate thermal treatment and three-dimensional (3D) p-n junction solar cells fabricated by depositing n-type semiconductor layers onto the nanoporous p-type thin films show considerable photovoltaic performance compared with conventional thin film p-n junction solar cells. Spin-coated p-type Cu2ZnSnS4 (CZTS) thin films prepared using metal chlorides and thiourea show unique nanoporous thin film morphology, which is composed of a cluster of CZTS nanograins of 50-500 nm, and the obvious 3D p-n junction structure is fabricated by the deposition of n-type CdS on the nanoporous CZTS thin films by chemical bath deposition. The photovoltaic properties of 3D p-n junction CZTS solar cells are predominantly affected by the scale of CZTS nanograins, which is easily controlled by the sulfurization temperature of CZTS precursor films. The scale of CZTS nanograins determines the minority carrier transportation within the 3D p-n junction between CZTS and CdS, which are closely related with the photocurrent of series resistance of 3D p-n junction solar cells. 3D p-n junction CZTS solar cells with nanograins below 100 nm show power conversion efficiency of 5.02%, which is comparable with conventional CZTS thin film solar cells.Nanoporous p-type semiconductor thin films prepared by a simple solution-based process with appropriate thermal treatment and three-dimensional (3D) p-n junction solar cells fabricated by depositing n-type semiconductor layers onto the nanoporous p-type thin films show considerable photovoltaic performance compared with conventional thin film p-n junction solar cells. Spin-coated p-type Cu2ZnSnS4 (CZTS) thin films prepared using metal chlorides and thiourea show unique nanoporous thin film morphology, which is composed of a cluster of CZTS nanograins of 50-500 nm, and the obvious 3D p-n junction structure is fabricated by the deposition of n-type CdS on the

  11. Multimodal-3D imaging based on μMRI and μCT techniques bridges the gap with histology in visualization of the bone regeneration process.

    PubMed

    Sinibaldi, R; Conti, A; Sinjari, B; Spadone, S; Pecci, R; Palombo, M; Komlev, V S; Ortore, M G; Tromba, G; Capuani, S; De Luca, F; Caputi, S; Traini, T; Della Penna, S

    2017-06-07

    Bone repair/regeneration is usually investigated through x-ray computed microtomography (μCT) supported by histology of extracted samples, to analyze biomaterial structure and new bone formation processes. Magnetic Resonance Imaging (μMRI) shows a richer tissue contrast than μCT, despite at lower resolution, and could be combined with μCT in the perspective of conducting non-destructive 3D investigations of bone. A pipeline designed to combine μMRI and μCT images of bone samples is here described and applied on samples of extracted human jawbone core following bone graft. We optimized the co-registration procedure between μCT and μMRI images to avoid bias due to the different resolutions and contrasts. Furthermore, we used an Adaptive Multivariate Clustering, grouping homologous voxels in the co-registered images, to visualize different tissue types within a fused 3D metastructure. The tissue grouping matched the 2D histology applied only on one slice, thus extending the histology labelling in 3D. Specifically, in all samples we could separate and map two types of regenerated bone, calcified tissue, soft tissues and/or fat and marrow space. Remarkably, μMRI and μCT alone were not able to separate the two types of regenerated bone. Finally, we computed volumes of each tissue in the 3D metastructures, which might be exploited by quantitative simulation. The 3D metastructure obtained through our pipeline represents a first step to bridge the gap between the quality of information obtained from 2D optical microscopy and the 3D mapping of the bone tissue heterogeneity, and could allow researchers and clinicians to non-destructively characterize and follow-up bone regeneration. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  12. A 3d-3d appetizer

    NASA Astrophysics Data System (ADS)

    Pei, Du; Ye, Ke

    2016-11-01

    We test the 3d-3d correspondence for theories that are labeled by Lens spaces. We find a full agreement between the index of the 3d N=2 "Lens space theory" T [ L( p, 1)] and the partition function of complex Chern-Simons theory on L( p, 1). In particular, for p = 1, we show how the familiar S 3 partition function of Chern-Simons theory arises from the index of a free theory. For large p, we find that the index of T[ L( p, 1)] becomes a constant independent of p. In addition, we study T[ L( p, 1)] on the squashed three-sphere S b 3 . This enables us to see clearly, at the level of partition function, to what extent G ℂ complex Chern-Simons theory can be thought of as two copies of Chern-Simons theory with compact gauge group G.

  13. 3d-3d correspondence revisited

    DOE PAGES

    Chung, Hee -Joong; Dimofte, Tudor; Gukov, Sergei; ...

    2016-04-21

    In fivebrane compactifications on 3-manifolds, we point out the importance of all flat connections in the proper definition of the effective 3d N = 2 theory. The Lagrangians of some theories with the desired properties can be constructed with the help of homological knot invariants that categorify colored Jones polynomials. Higgsing the full 3d theories constructed this way recovers theories found previously by Dimofte-Gaiotto-Gukov. As a result, we also consider the cutting and gluing of 3-manifolds along smooth boundaries and the role played by all flat connections in this operation.

  14. 3d-3d correspondence revisited

    SciTech Connect

    Chung, Hee -Joong; Dimofte, Tudor; Gukov, Sergei; Sułkowski, Piotr

    2016-04-21

    In fivebrane compactifications on 3-manifolds, we point out the importance of all flat connections in the proper definition of the effective 3d N = 2 theory. The Lagrangians of some theories with the desired properties can be constructed with the help of homological knot invariants that categorify colored Jones polynomials. Higgsing the full 3d theories constructed this way recovers theories found previously by Dimofte-Gaiotto-Gukov. As a result, we also consider the cutting and gluing of 3-manifolds along smooth boundaries and the role played by all flat connections in this operation.

  15. An open source image processing method to quantitatively assess tissue growth after non-invasive magnetic resonance imaging in human bone marrow stromal cell seeded 3D polymeric scaffolds.

    PubMed

    Leferink, Anne M; Fratila, Raluca M; Koenrades, Maaike A; van Blitterswijk, Clemens A; Velders, Aldrik; Moroni, Lorenzo

    2014-01-01

    Monitoring extracellular matrix (ECM) components is one of the key methods used to determine tissue quality in three-dimensional (3D) scaffolds for regenerative medicine and clinical purposes. This is even more important when multipotent human bone marrow stromal cells (hMSCs) are used, as it could offer a method to understand in real time the dynamics of stromal cell differentiation and eventually steer it into the desired lineage. Magnetic Resonance Imaging (MRI) is a promising tool to overcome the challenge of a limited transparency in opaque 3D scaffolds. Technical limitations of MRI involve non-uniform background intensity leading to fluctuating background signals and therewith complicating quantifications on the retrieved images. We present a post-imaging processing sequence that is able to correct for this non-uniform background intensity. To test the processing sequence we investigated the use of MRI for in vitro monitoring of tissue growth in three-dimensional poly(ethylene oxide terephthalate)-poly(butylene terephthalate) (PEOT/PBT) scaffolds. Results showed that MRI, without the need to use contrast agents, is a promising non-invasive tool to quantitatively monitor ECM production and cell distribution during in vitro culture in 3D porous tissue engineered constructs.

  16. An Open Source Image Processing Method to Quantitatively Assess Tissue Growth after Non-Invasive Magnetic Resonance Imaging in Human Bone Marrow Stromal Cell Seeded 3D Polymeric Scaffolds

    PubMed Central

    Leferink, Anne M.; Fratila, Raluca M.; Koenrades, Maaike A.; van Blitterswijk, Clemens A.; Velders, Aldrik; Moroni, Lorenzo

    2014-01-01

    Monitoring extracellular matrix (ECM) components is one of the key methods used to determine tissue quality in three-dimensional (3D) scaffolds for regenerative medicine and clinical purposes. This is even more important when multipotent human bone marrow stromal cells (hMSCs) are used, as it could offer a method to understand in real time the dynamics of stromal cell differentiation and eventually steer it into the desired lineage. Magnetic Resonance Imaging (MRI) is a promising tool to overcome the challenge of a limited transparency in opaque 3D scaffolds. Technical limitations of MRI involve non-uniform background intensity leading to fluctuating background signals and therewith complicating quantifications on the retrieved images. We present a post-imaging processing sequence that is able to correct for this non-uniform background intensity. To test the processing sequence we investigated the use of MRI for in vitro monitoring of tissue growth in three-dimensional poly(ethylene oxide terephthalate)–poly(butylene terephthalate) (PEOT/PBT) scaffolds. Results showed that MRI, without the need to use contrast agents, is a promising non-invasive tool to quantitatively monitor ECM production and cell distribution during in vitro culture in 3D porous tissue engineered constructs. PMID:25502022

  17. 3D Surgical Simulation

    PubMed Central

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

    2009-01-01

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

  18. Beyond the answer: post-error processes.

    PubMed

    Kleiter, G D; Schwarzenbacher, K

    1989-08-01

    When you suspect that you just gave an erroneous answer to a question you stop and rethink. Suspected errors lead to a shift in the control and content of cognitive processes. In the present experiment we investigated the influence of errors upon heart rates and response latencies. Sixty-four subjects participated in an experiment in which each subject solved a sequence of 60 verbal analogies. The results demonstrated increased latencies after errors and decelerated heart rates during the post-error period. The results were explained by a psychophysiological model in which the septo-hippocampal system functions as a control system which coordinates the priority and selection of cognitive processes. Error detection suppresses strategies which otherwise prevent looping and iterative reanalyses of old material. The inhibition is also responsible for the cardiac slowing during the post-error period.

  19. Solution-processed, hybrid 2D/3D MoS2/Si heterostructures with superior junction characteristics

    NASA Astrophysics Data System (ADS)

    Mukherjee, S.; Biswas, S.; Das, S.; Ray, S. K.

    2017-03-01

    We report a theoretical and experimental investigation of the hybrid heterostructure interfaces between atomically thin MoS2 nanocrystals (NCs) on Si platform for their potential applications towards next-generation electrical and optical devices. Mie theory-based numerical analysis and COMSOL simulations based on the finite element method have been utilized to study the optical absorption characteristics and light-matter interactions in variable-sized MoS2 NCs. The size-dependent absorption characteristics and the enhancement of electric field of the heterojunction in the UV-visible spectral range agree well with the experimental results. A lithography-free, wafer-scale, 2D material on a 3D substrate hybrid vertical heterostructure has been fabricated using colloidal n-MoS2 NCs on p-Si. The fabricated p-n heterojunction exhibited excellent junction characteristics with a high rectification ratio suitable for voltage clipper and rectifier applications. The current-voltage characteristics of the devices under illumination have been performed in the temperature range of 10-300 K. The device exhibits a high photo-to-dark current ratio of ˜3 × 103 and a responsivity comparable to a commercial Si photodetector. The excellent heterojunction characteristics demonstrate the great potential of MoS2 NC-based hybrid electronic and optoelectronic devices in the near future.

  20. Solution-processed, hybrid 2D/3D MoS2/Si heterostructures with superior junction characteristics.

    PubMed

    Mukherjee, S; Biswas, S; Das, S; Ray, S K

    2017-03-01

    We report a theoretical and experimental investigation of the hybrid heterostructure interfaces between atomically thin MoS2 nanocrystals (NCs) on Si platform for their potential applications towards next-generation electrical and optical devices. Mie theory-based numerical analysis and COMSOL simulations based on the finite element method have been utilized to study the optical absorption characteristics and light-matter interactions in variable-sized MoS2 NCs. The size-dependent absorption characteristics and the enhancement of electric field of the heterojunction in the UV-visible spectral range agree well with the experimental results. A lithography-free, wafer-scale, 2D material on a 3D substrate hybrid vertical heterostructure has been fabricated using colloidal n-MoS2 NCs on p-Si. The fabricated p-n heterojunction exhibited excellent junction characteristics with a high rectification ratio suitable for voltage clipper and rectifier applications. The current-voltage characteristics of the devices under illumination have been performed in the temperature range of 10-300 K. The device exhibits a high photo-to-dark current ratio of ∼3 × 10(3) and a responsivity comparable to a commercial Si photodetector. The excellent heterojunction characteristics demonstrate the great potential of MoS2 NC-based hybrid electronic and optoelectronic devices in the near future.

  1. Functional response of osteoblasts in functionally gradient titanium alloy mesh arrays processed by 3D additive manufacturing.

    PubMed

    Nune, K C; Kumar, A; Misra, R D K; Li, S J; Hao, Y L; Yang, R

    2017-02-01

    We elucidate here the osteoblasts functions and cellular activity in 3D printed interconnected porous architecture of functionally gradient Ti-6Al-4V alloy mesh structures in terms of cell proliferation and growth, distribution of cell nuclei, synthesis of proteins (actin, vinculin, and fibronectin), and calcium deposition. Cell culture studies with pre-osteoblasts indicated that the interconnected porous architecture of functionally gradient mesh arrays was conducive to osteoblast functions. However, there were statistically significant differences in the cellular response depending on the pore size in the functionally gradient structure. The interconnected porous architecture contributed to the distribution of cells from the large pore size (G1) to the small pore size (G3), with consequent synthesis of extracellular matrix and calcium precipitation. The gradient mesh structure significantly impacted cell adhesion and influenced the proliferation stage, such that there was high distribution of cells on struts of the gradient mesh structure. Actin and vinculin showed a significant difference in normalized expression level of protein per cell, which was absent in the case of fibronectin. Osteoblasts present on mesh struts formed a confluent sheet, bridging the pores through numerous cytoplasmic extensions. The gradient mesh structure fabricated by electron beam melting was explored to obtain fundamental insights on cellular activity with respect to osteoblast functions. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Structural control on the Tohoku earthquake rupture process investigated by 3D FEM, tsunami and geodetic data.

    PubMed

    Romano, F; Trasatti, E; Lorito, S; Piromallo, C; Piatanesi, A; Ito, Y; Zhao, D; Hirata, K; Lanucara, P; Cocco, M

    2014-07-09

    The 2011 Tohoku earthquake (Mw = 9.1) highlighted previously unobserved features for megathrust events, such as the large slip in a relatively limited area and the shallow rupture propagation. We use a Finite Element Model (FEM), taking into account the 3D geometrical and structural complexities up to the trench zone, and perform a joint inversion of tsunami and geodetic data to retrieve the earthquake slip distribution. We obtain a close spatial correlation between the main deep slip patch and the local seismic velocity anomalies, and large shallow slip extending also to the North coherently with a seismically observed low-frequency radiation. These observations suggest that the friction controlled the rupture, initially confining the deeper rupture and then driving its propagation up to the trench, where it spreads laterally. These findings are relevant to earthquake and tsunami hazard assessment because they may help to detect regions likely prone to rupture along the megathrust, and to constrain the probability of high slip near the trench. Our estimate of ~40 m slip value around the JFAST (Japan Trench Fast Drilling Project) drilling zone contributes to constrain the dynamic shear stress and friction coefficient of the fault obtained by temperature measurements to ~0.68 MPa and ~0.10, respectively.

  3. Structural control on the Tohoku earthquake rupture process investigated by 3D FEM, tsunami and geodetic data

    PubMed Central

    Romano, F.; Trasatti, E.; Lorito, S.; Piromallo, C.; Piatanesi, A.; Ito, Y.; Zhao, D.; Hirata, K.; Lanucara, P.; Cocco, M.

    2014-01-01

    The 2011 Tohoku earthquake (Mw = 9.1) highlighted previously unobserved features for megathrust events, such as the large slip in a relatively limited area and the shallow rupture propagation. We use a Finite Element Model (FEM), taking into account the 3D geometrical and structural complexities up to the trench zone, and perform a joint inversion of tsunami and geodetic data to retrieve the earthquake slip distribution. We obtain a close spatial correlation between the main deep slip patch and the local seismic velocity anomalies, and large shallow slip extending also to the North coherently with a seismically observed low-frequency radiation. These observations suggest that the friction controlled the rupture, initially confining the deeper rupture and then driving its propagation up to the trench, where it spreads laterally. These findings are relevant to earthquake and tsunami hazard assessment because they may help to detect regions likely prone to rupture along the megathrust, and to constrain the probability of high slip near the trench. Our estimate of ~40 m slip value around the JFAST (Japan Trench Fast Drilling Project) drilling zone contributes to constrain the dynamic shear stress and friction coefficient of the fault obtained by temperature measurements to ~0.68 MPa and ~0.10, respectively. PMID:25005351

  4. Laser processing of SnO2 electrode materials for manufacturing of 3D micro-batteries

    NASA Astrophysics Data System (ADS)

    Kohler, R.; Proell, J.; Ulrich, S.; Przybylski, M.; Pfleging, W.

    2011-03-01

    The material development for advanced lithium-ion batteries plays an important role in future mobile applications and energy storage systems. It is assumed that electrode materials made of nano-composited materials will improve battery lifetime and will lead to an enhancement of lithium diffusion and thus improve battery capacity and cyclability. A major problem concerning thin film electrodes is, that increasing film thickness leads to an increase in lithium diffusion path lengths and thereby a decrease in power density. To overcome this problem, the investigation of a 3D-battery system with an increased surface area is necessary. UV-laser micromachining was applied to create defined line or grating structures via mask imaging. SnO2 is a highly investigated anode material for lithium-ion batteries. Yet, the enormous volume changes occurring during electrochemical cycling lead to immense loss of capacity. The formation of micropatterns via laser ablation to create structures which enable the compensation of the volume expansion was investigated in detail. Thin films of SnO2 were deposited in Ar:O2 atmosphere via r.f. magnetron sputtering on silicon and stainless steel substrates. The thin films were studied with X-ray diffraction to determine their crystallinity. The electrochemical properties of the manufactured films were investigated via electrochemical cycling against a lithium anode.

  5. The development of all-polymer-based piezoelectrically active photocurable resin for 3D printing process (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Baker, Evan; Chu, Weishen; Ware, Henry Oliver T.; Farsheed, Adam C.; Sun, Cheng

    2017-02-01

    We present in this work the development and experimental validation of a new piezoelectric material (V-Ink) designed for compatibility with projection stereolithography additive manufacturing techniques. Piezoelectric materials generate a voltage output when a stress is applied to the material, and also can be actuated by using an external voltage and power source. This new material opens up new opportunities for functional devices to be developed and rapidly produced at low cost using emerging 3D printing techniques. The new piezoelectric material was able to generate 115mV under 1N of strain after being polled at 80°C for 40 minutes and the optimal results had a piezoelectric coefficient of 105x10^(-3)V.m/N. The current iteration of the material is a suspension, although further work is ongoing to make the resin a true solution. The nature of the suspension was characterized by a time-lapse monitoring and through viscosity testing. The potential exists to further increase the piezoelectric properties of this material by integrating a mechanical to electrical enhancer such as carbon nanotubes or barium titanate into the material. Such materials need to be functionalized to be integrated within the material, which is currently being explored. Printing with this material on a "continuous SLA" printer that we have developed will reduce build times by an order of magnitude to allow for mass manufacturing. Pairing those two advancements will enable faster printing and enhanced piezoelectric properties.

  6. Test Anxiety and Post Processing Interference. 2.

    DTIC Science & Technology

    1991-07-01

    behaviors. Journal of Educational Psychology , 72, 16-20. Desiderato, 0., & Koskinen, P. (1969). Anxiety, study habits, and academic achievement. Journal...anxiety: Literature review and a revised worry-emotionality scale. Journal of Educational Psychology , 73, 541-555. Sarason, I.G. (1972). Experimental... educational psychology . Journal of Educational Psychology , 71, 573-582. Tobias, S. (1984a). Test anxiety and post processing interference. New York: City

  7. A versatile and low-cost 3D acquisition and processing pipeline for collecting mass of archaeological findings on the field

    NASA Astrophysics Data System (ADS)

    Gattet, E.; Devogelaere, J.; Raffin, R.; Bergerot, L.; Daniel, M.; Jockey, Ph.; De Luca, L.

    2015-02-01

    In recent years, advances in the fields of photogrammetry and computer vision have produced several solutions for generating 3D reconstruction starting from simple images. Even if the potentialities of the image-based 3D reconstruction approach are nowadays very well-known in terms of reliability, accuracy and flexibility, there is still a lack of low-cost, open-source and automated solutions for collecting mass of archaeological findings, specially if one consider the real (and non theoretical) contextual aspects of a digitization campaign on the field (number of objects to acquire, available time, lighting conditions, equipment transport, budget, etc...) as well as the accuracy requirements for an in-depth shape analysis and classification purpose. In this paper we present a prototype system (integrating hardware and software) for the 3D acquisition, geometric reconstruction, documentation and archiving of large collections of archaeological findings. All the aspects of our approach are based on high-end image-based modeling techniques and designed basing on an accurate analysis of the typical field conditions of an archaeological campaign, as well as on the specific requirements of archaeological finding documentation and analysis. This paper presents all the aspects integrated into the prototype: - a hardware development of a transportable photobooth for the automated image acquisition consisting of a turntable and three DSLR controlled by a microcontroller; - an automatic image processing pipeline (based on Apero/Micmac) including mask generation, tie-point extraction, bundle adjustment, multi-view stereo correlation, point cloud generation, surface reconstruction; - a versatile (off-line/on-line) portable database for associating descriptive attributes (archaeological description) to the 3D digitizations on site; - a platform for data-gathering, archiving and sharing collections of 3D digitizations on the Web. The presentation and the assessment of this

  8. 3D and Education

    NASA Astrophysics Data System (ADS)

    Meulien Ohlmann, Odile

    2013-02-01

    Today the industry offers a chain of 3D products. Learning to "read" and to "create in 3D" becomes an issue of education of primary importance. 25 years professional experience in France, the United States and Germany, Odile Meulien set up a personal method of initiation to 3D creation that entails the spatial/temporal experience of the holographic visual. She will present some different tools and techniques used for this learning, their advantages and disadvantages, programs and issues of educational policies, constraints and expectations related to the development of new techniques for 3D imaging. Although the creation of display holograms is very much reduced compared to the creation of the 90ies, the holographic concept is spreading in all scientific, social, and artistic activities of our present time. She will also raise many questions: What means 3D? Is it communication? Is it perception? How the seeing and none seeing is interferes? What else has to be taken in consideration to communicate in 3D? How to handle the non visible relations of moving objects with subjects? Does this transform our model of exchange with others? What kind of interaction this has with our everyday life? Then come more practical questions: How to learn creating 3D visualization, to learn 3D grammar, 3D language, 3D thinking? What for? At what level? In which matter? for whom?

  9. Embedding objects during 3D printing to add new functionalities

    PubMed Central

    2016-01-01

    A novel method for integrating and embedding objects to add new functionalities during 3D printing based on fused deposition modeling (FDM) (also known as fused filament fabrication or molten polymer deposition) is presented. Unlike typical 3D printing, FDM-based 3D printing could allow objects to be integrated and embedded during 3D printing and the FDM-based 3D printed devices do not typically require any post-processing and finishing. Thus, various fluidic devices with integrated glass cover slips or polystyrene films with and without an embedded porous membrane, and optical devices with embedded Corning® Fibrance™ Light-Diffusing Fiber were 3D printed to demonstrate the versatility of the FDM-based 3D printing and embedding method. Fluid perfusion flow experiments with a blue colored food dye solution were used to visually confirm fluid flow and/or fluid perfusion through the embedded porous membrane in the 3D printed fluidic devices. Similar to typical 3D printed devices, FDM-based 3D printed devices are translucent at best unless post-polishing is performed and optical transparency is highly desirable in any fluidic devices; integrated glass cover slips or polystyrene films would provide a perfect optical transparent window for observation and visualization. In addition, they also provide a compatible flat smooth surface for biological or biomolecular applications. The 3D printed fluidic devices with an embedded porous membrane are applicable to biological or chemical applications such as continuous perfusion cell culture or biocatalytic synthesis but without the need for any post-device assembly and finishing. The 3D printed devices with embedded Corning® Fibrance™ Light-Diffusing Fiber would have applications in display, illumination, or optical applications. Furthermore, the FDM-based 3D printing and embedding method could also be utilized to print casting molds with an integrated glass bottom for polydimethylsiloxane (PDMS) device replication. These

  10. Embedding objects during 3D printing to add new functionalities.

    PubMed

    Yuen, Po Ki

    2016-07-01

    A novel method for integrating and embedding objects to add new functionalities during 3D printing based on fused deposition modeling (FDM) (also known as fused filament fabrication or molten polymer deposition) is presented. Unlike typical 3D printing, FDM-based 3D printing could allow objects to be integrated and embedded during 3D printing and the FDM-based 3D printed devices do not typically require any post-processing and finishing. Thus, various fluidic devices with integrated glass cover slips or polystyrene films with and without an embedded porous membrane, and optical devices with embedded Corning(®) Fibrance™ Light-Diffusing Fiber were 3D printed to demonstrate the versatility of the FDM-based 3D printing and embedding method. Fluid perfusion flow experiments with a blue colored food dye solution were used to visually confirm fluid flow and/or fluid perfusion through the embedded porous membrane in the 3D printed fluidic devices. Similar to typical 3D printed devices, FDM-based 3D printed devices are translucent at best unless post-polishing is performed and optical transparency is highly desirable in any fluidic devices; integrated glass cover slips or polystyrene films would provide a perfect optical transparent window for observation and visualization. In addition, they also provide a compatible flat smooth surface for biological or biomolecular applications. The 3D printed fluidic devices with an embedded porous membrane are applicable to biological or chemical applications such as continuous perfusion cell culture or biocatalytic synthesis but without the need for any post-device assembly and finishing. The 3D printed devices with embedded Corning(®) Fibrance™ Light-Diffusing Fiber would have applications in display, illumination, or optical applications. Furthermore, the FDM-based 3D printing and embedding method could also be utilized to print casting molds with an integrated glass bottom for polydimethylsiloxane (PDMS) device replication

  11. Improved border sharpness of post-infarct scar by a novel self-navigated free-breathing high-resolution 3D whole-heart inversion recovery magnetic resonance approach.

    PubMed

    Rutz, Tobias; Piccini, Davide; Coppo, Simone; Chaptinel, Jerome; Ginami, Giulia; Vincenti, Gabriella; Stuber, Matthias; Schwitter, Juerg

    2016-12-01

    The border zone of post-infarction myocardial scar as identified by late gadolinium enhancement (LGE) has been identified as a substrate for arrhythmias and consequently, high-resolution 3D scar information is potentially useful for planning of electrophysiological interventions. This study evaluates the performance of a novel high-resolution 3D self-navigated free-breathing inversion recovery magnetic resonance pulse sequence (3D-SN-LGE) vs. conventional 2D breath-hold LGE (2D-LGE) with regard to sharpness of borders (SBorder) of post-infarction scar. Patients with post-infarction scar underwent two magnetic resonance examinations for conventional 2D-LGE and high-resolution 3D-SN-LGE acquisitions (both 15 min after 0.2 mmol/kg Gadobutrol IV) at 1.5T. In the prototype 3D-SN-LGE sequence, each ECG-triggered radial steady-state-free-precession read-out segment is preceded by a non-slice-selective inversion pulse. Scar volume and SBorder were assessed on 2D-LGE and matching reconstructed high-resolution 3D-SN-LGE short-axis slices. In 16 patients (four females, 58 ± 10y) all scars visualized by 2D-LGE could be identified on 3D-SN-LGE (time between 2D-LGE and 3D-SN-LGE 48 ± 53 days). A good agreement of scar volume by 3D-SN-LGE vs. 2D-LGE was found (Bland-Altman: -3.7 ± 3.4 ml, correlation: r = 0.987, p < 0.001) with a small difference in scar volume (20.5 (15.8, 35.2) ml vs. 24.5 (20.0, 41.9)) ml, respectively, p = 0.002] and a good intra- and interobserver variability (1.1 ± 4.1 and -1.1 ± 11.9 ml, respectively). SBorder of border "scar to non-infarcted myocardium" was superior on 3D-SN-LGE vs. 2D-LGE: 0.180 ± 0.044 vs. 0.083 ± 0.038, p < 0.001. Detection and quantification of myocardial scar by 3D-SN-LGE is feasible and accurate in comparison to 2D-LGE. The high spatial resolution of the 3D sequence improves delineation of scar borders.

  12. Rift processes and crustal structure of the Amundsen Sea Embayment, West Antarctica, from 3D potential field modelling

    NASA Astrophysics Data System (ADS)

    Kalberg, Thomas; Gohl, Karsten; Eagles, Graeme; Spiegel, Cornelia

    2015-12-01

    The Amundsen Sea Embayment of West Antarctica is of particular interest as it provides critical geological boundary conditions in better understanding the dynamic behavior of the West Antarctic Ice Sheet, which is undergoing rapid ice loss in the Amundsen Sea sector. One of the highly debated hypothesis is whether this region has been affected by the West Antarctic Rift System, which is one of the largest in the world and the dominating tectonic feature in West Antarctica. Previous geophysical studies suggested an eastward continuation of this rift system into the Amundsen Sea Embayment. This geophysical study of the Amundsen Sea Embayment presents a compilation of data collected during two RV Polarstern expeditions in the Amundsen Sea Embayment of West Antarctica in 2006 and 2010. Bathymetry and satellite-derived gravity data of the Amundsen Sea Embayment complete the dataset. Our 3-D gravity and magnetic models of the lithospheric architecture and development of this Pacific margin improve previous interpretations from 2-D models of the region. The crust-mantle boundary beneath the continental rise and shelf is between 14 and 29 km deep. The imaged basement structure can be related to rift basins within the Amundsen Sea Embayment, some of which can be interpreted as products of the Cretaceous rift and break-up phase and some as products of later propagation of the West Antarctic Rift System into the region. An estimate of the flexural rigidity of the lithosphere reveals a thin elastic thickness in the eastern embayment which increases towards the west. The results are comparable to estimates in other rift systems such as the Basin and Range province or the East African Rift. Based on these results, we infer an arm of the West Antarctic Rift System is superposed on a distributed Cretaceous rift province in the Amundsen Sea Embayment. Finally, the embayment was affected by magmatism from discrete sources along the Pacific margin of West Antarctica in the Cenozoic.

  13. Unassisted 3D camera calibration

    NASA Astrophysics Data System (ADS)

    Atanassov, Kalin; Ramachandra, Vikas; Nash, James; Goma, Sergio R.

    2012-03-01

    With the rapid growth of 3D technology, 3D image capture has become a critical part of the 3D feature set on mobile phones. 3D image quality is affected by the scene geometry as well as on-the-device processing. An automatic 3D system usually assumes known camera poses accomplished by factory calibration using a special chart. In real life settings, pose parameters estimated by factory calibration can be negatively impacted by movements of the lens barrel due to shaking, focusing, or camera drop. If any of these factors displaces the optical axes of either or both cameras, vertical disparity might exceed the maximum tolerable margin and the 3D user may experience eye strain or headaches. To make 3D capture more practical, one needs to consider unassisted (on arbitrary scenes) calibration. In this paper, we propose an algorithm that relies on detection and matching of keypoints between left and right images. Frames containing erroneous matches, along with frames with insufficiently rich keypoint constellations, are detected and discarded. Roll, pitch yaw , and scale differences between left and right frames are then estimated. The algorithm performance is evaluated in terms of the remaining vertical disparity as compared to the maximum tolerable vertical disparity.

  14. Bioprinting of 3D hydrogels.

    PubMed

    Stanton, M M; Samitier, J; Sánchez, S

    2015-08-07

    Three-dimensional (3D) bioprinting has recently emerged as an extension of 3D material printing, by using biocompatible or cellular components to build structures in an additive, layer-by-layer methodology for encapsulation and culture of cells. These 3D systems allow for cell culture in a suspension for formation of highly organized tissue or controlled spatial orientation of cell environments. The in vitro 3D cellular environments simulate the complexity of an in vivo environment and natural extracellular matrices (ECM). This paper will focus on bioprinting utilizing hydrogels as 3D scaffolds. Hydrogels are advantageous for cell culture as they are highly permeable to cell culture media, nutrients, and waste products generated during metabolic cell processes. They have the ability to be fabricated in customized shapes with various material properties with dimensions at the micron scale. 3D hydrogels are a reliable method for biocompatible 3D printing and have applications in tissue engineering, drug screening, and organ on a chip models.

  15. Refined 3d-3d correspondence

    NASA Astrophysics Data System (ADS)

    Alday, Luis F.; Genolini, Pietro Benetti; Bullimore, Mathew; van Loon, Mark

    2017-04-01

    We explore aspects of the correspondence between Seifert 3-manifolds and 3d N = 2 supersymmetric theories with a distinguished abelian flavour symmetry. We give a prescription for computing the squashed three-sphere partition functions of such 3d N = 2 theories constructed from boundary conditions and interfaces in a 4d N = 2∗ theory, mirroring the construction of Seifert manifold invariants via Dehn surgery. This is extended to include links in the Seifert manifold by the insertion of supersymmetric Wilson-'t Hooft loops in the 4d N = 2∗ theory. In the presence of a mass parameter cfor the distinguished flavour symmetry, we recover aspects of refined Chern-Simons theory with complex gauge group, and in particular construct an analytic continuation of the S-matrix of refined Chern-Simons theory.

  16. Application of characterization, modelling, and analytics towards understanding process-structure linkages in metallic 3D printing

    NASA Astrophysics Data System (ADS)

    Groeber, M. A.; Schwalbach, E.; Donegan, S.; Chaput, K.; Butler, T.; Miller, J.

    2017-07-01

    This paper presents methods for combining process monitoring, thermal modelling and microstructure characterization together to draw process-to-structure relationships in metal additive manufacturing. The paper discusses heterogeneities in the local processing conditions within additively manufactured components and how they affect the resulting material structure. Methods for registering and fusing disparate data sources are presented, and some effort is made to discuss the utility of different data sources for specific microstructural features of interest. It is the intent that this paper will highlight the need for improved understanding of metallic additive manufacturing processes and show that combining experimental data with modelling and advanced data processing and analytics methods will accelerate that understanding.

  17. A 3d-3d appetizer

    DOE PAGES

    Pei, Du; Ye, Ke

    2016-11-02

    Here, we test the 3d-3d correspondence for theories that are labeled by Lens spaces. We find a full agreement between the index of the 3d N=2 “Lens space theory” T [L(p, 1)] and the partition function of complex Chern-Simons theory on L(p, 1). In particular, for p = 1, we show how the familiar S3 partition function of Chern-Simons theory arises from the index of a free theory. For large p, we find that the index of T[L(p, 1)] becomes a constant independent of p. In addition, we study T[L(p, 1)] on the squashed three-sphere Sb3. This enables us tomore » see clearly, at the level of partition function, to what extent GC complex Chern-Simons theory can be thought of as two copies of Chern-Simons theory with compact gauge group G.« less

  18. A 3d-3d appetizer

    SciTech Connect

    Pei, Du; Ye, Ke

    2016-11-02

    Here, we test the 3d-3d correspondence for theories that are labeled by Lens spaces. We find a full agreement between the index of the 3d N=2 “Lens space theory” T [L(p, 1)] and the partition function of complex Chern-Simons theory on L(p, 1). In particular, for p = 1, we show how the familiar S3 partition function of Chern-Simons theory arises from the index of a free theory. For large p, we find that the index of T[L(p, 1)] becomes a constant independent of p. In addition, we study T[L(p, 1)] on the squashed three-sphere Sb3. This enables us to see clearly, at the level of partition function, to what extent GC complex Chern-Simons theory can be thought of as two copies of Chern-Simons theory with compact gauge group G.

  19. Workflow for the integration of a realistic 3D geomodel in process simulations using different cell types and advanced scientific visualization: Variations on a synthetic salt diapir

    NASA Astrophysics Data System (ADS)

    Görz, Ines; Herbst, Martin; Börner, Jana H.; Zehner, Björn

    2017-03-01

    The purpose of this study is to use one complex geological 3D model for numerical simulations of various physical processes in process-specific simulation software. To do this, the 3D model has to be discretized according to different cell types, depending on the requirements of the simulation method. We used a salt structure with a diapir and its deformed host rock to produce two 3D models describing the boundary surfaces of the structure: one very simplified model consisting of cuboid surfaces and a realistic model consisting of irregular boundary surfaces. We provide a workflow for how to generate hexahedral, tetrahedral and spherical volume representations of these two geometries. We utilized the volume representations to simulate temperature, displacement and transient electromagnetic fields. We can show that the simulation results closely reflect the input geometry and that it is worth the effort to produce geometric models that are as realistic as possible. Additionally, we provide a workflow for simultaneous visualization and analysis of the simulation results. Scientific visualization is an important tool for deriving knowledge from complex investigations.

  20. Quantifying the impact of early calcite cementation on the reservoir quality of carbonate rocks: A 3D process-based model

    NASA Astrophysics Data System (ADS)

    Hosa, Aleksandra; Wood, Rachel

    2017-06-01

    The reservoir properties of carbonate rocks are controlled by both deposition and diagenesis. The latter includes the early precipitation of calcite cements, which can exert a strong control on the evolution of subsequent diagenetic pathways. We quantify the impact of early marine cement growth in grainstones on evolving pore space by examining trends in the relationship between cementation and permeability using a 3D process-based model (Calcite3D). The model assumes varying proportions of polycrystalline and monocrystalline grain types, upon which we grow isopachous and syntaxial calcite cement types, respectively. We model two syntaxial cement shapes, compact and elongated, that approximate the geometries of typical rhombohedral calcite forms. Results demonstrate the effect of cement competition: an increasing proportion of monocrystalline grains creates stronger competition and a reduction in the impact of individual grains on final calcite cement volume and porosity. Isopachous cement is effective in closing pore throats and limiting permeability. We also show that the impact of syntaxial cement on porosity occlusion and therefore flow is highly dependent on monocrystalline grain location and the orientation of crystal axes. This demonstrates the importance of diagenetic overprint in controlling the evolution of rock properties, but also that this process can be essentially random. We also show that diagenesis alone can create notable heterogeneity in the permeability of carbonates. While Calcite3D is successful in modelling realistic changes in cement volumes and pore space morphology, modelled permeabilities (0.01 -30D) are above the range reported in reservoir grainstones due to the very high permeability of the initial synthetic sediment deposit (58.9D). Poroperm data generated by Calcite3D, however, exhibits a linear relationship between the logarithms of porosity and permeability with a high coefficient of determination, as observed in natural media.

  1. Process optimization for a 3D optical coupler and waveguide fabrication on a single substrate using buffer coat material

    NASA Astrophysics Data System (ADS)

    Summitt, Chris; Wang, Sunglin; Johnson, Lee; Zaverton, Melissa; Ge, Tao; Milster, Tom; Takashima, Yuzuru

    2015-03-01

    We have developed a hybrid lithography process necessary to fabricate a vertical optical coupler and an array of waveguide structures using the same buffer coat material on a single substrate. A virtual vernier scale built into the process enables precise alignment of both structures.

  2. Integrated Tsunami Database: simulation and identification of seismic tsunami sources, 3D visualization and post-disaster assessment on the shore

    NASA Astrophysics Data System (ADS)

    Krivorot'ko, Olga; Kabanikhin, Sergey; Marinin, Igor; Karas, Adel; Khidasheli, David

    2013-04-01

    One of the most important problems of tsunami investigation is the problem of seismic tsunami source reconstruction. Non-profit organization WAPMERR (http://wapmerr.org) has provided a historical database of alleged tsunami sources around the world that obtained with the help of information about seaquakes. WAPMERR also has a database of observations of the tsunami waves in coastal areas. The main idea of presentation consists of determining of the tsunami source parameters using seismic data and observations of the tsunami waves on the shore, and the expansion and refinement of the database of presupposed tsunami sources for operative and accurate prediction of hazards and assessment of risks and consequences. Also we present 3D visualization of real-time tsunami wave propagation and loss assessment, characterizing the nature of the building stock in cities at risk, and monitoring by satellite images using modern GIS technology ITRIS (Integrated Tsunami Research and Information System) developed by WAPMERR and Informap Ltd. The special scientific plug-in components are embedded in a specially developed GIS-type graphic shell for easy data retrieval, visualization and processing. The most suitable physical models related to simulation of tsunamis are based on shallow water equations. We consider the initial-boundary value problem in Ω := {(x,y) ?R2 : x ?(0,Lx ), y ?(0,Ly ), Lx,Ly > 0} for the well-known linear shallow water equations in the Cartesian coordinate system in terms of the liquid flow components in dimensional form Here ?(x,y,t) defines the free water surface vertical displacement, i.e. amplitude of a tsunami wave, q(x,y) is the initial amplitude of a tsunami wave. The lateral boundary is assumed to be a non-reflecting boundary of the domain, that is, it allows the free passage of the propagating waves. Assume that the free surface oscillation data at points (xm, ym) are given as a measured output data from tsunami records: fm(t) := ? (xm, ym,t), (xm

  3. Mathematical modelling of physical and chemical processes of coal combustion in chamber furnaces of boiler aggregates based on the package of applied programs FIRE 3D

    NASA Astrophysics Data System (ADS)

    Gil, A. V.; Starchenko, A. V.

    2012-09-01

    The furnace processes of the combustion of poly-fraction high-ashes Ekibastuz coal in the furnace chamber of the boiler aggregate PK-39 and of the combustion of highly humid brown Berezov's coal in the furnace of the BKZ-210-140 boiler are investigated by mathematical modeling using the package of applied programs FIRE 3D [1-3]. Results of the numerical modeling of the processes of aerodynamics, heat exchange, and combustion in the furnace volume and their comparison with the results of nature tests are presented.

  4. 3D Imaging.

    ERIC Educational Resources Information Center

    Hastings, S. K.

    2002-01-01

    Discusses 3 D imaging as it relates to digital representations in virtual library collections. Highlights include X-ray computed tomography (X-ray CT); the National Science Foundation (NSF) Digital Library Initiatives; output peripherals; image retrieval systems, including metadata; and applications of 3 D imaging for libraries and museums. (LRW)

  5. 3D Imaging.

    ERIC Educational Resources Information Center

    Hastings, S. K.

    2002-01-01

    Discusses 3 D imaging as it relates to digital representations in virtual library collections. Highlights include X-ray computed tomography (X-ray CT); the National Science Foundation (NSF) Digital Library Initiatives; output peripherals; image retrieval systems, including metadata; and applications of 3 D imaging for libraries and museums. (LRW)

  6. Diamond in 3-D

    NASA Image and Video Library

    2004-08-20

    This 3-D, microscopic imager mosaic of a target area on a rock called Diamond Jenness was taken after NASA Mars Exploration Rover Opportunity ground into the surface with its rock abrasion tool for a second time. 3D glasses are necessary.

  7. Accomplishing Equilibrium in ALSEP: Demonstrations of Modified Process Chemistry on 3-D Printed Enhanced Annular Centrifugal Contactors

    SciTech Connect

    Brown, M. Alex; Wardle, Kent E.; Lumetta, Gregg; Gelis, Artem V.

    2016-12-01

    Here, the major components of the modified ALSEP process have been demonstrated on a modified 2-cm annular centrifugal contactor with an enhanced mixing zone using stable fission products and radiotracers. The results show that by decreasing the pH of the minor actinide stripping solution, using HEDTA instead of DTPA, and increasing contact time, the process is very effective in separating americium from the lanthanides and the fission products.

  8. Accomplishing Equilibrium in ALSEP: Demonstrations of Modified Process Chemistry on 3-D Printed Enhanced Annular Centrifugal Contactors

    DOE PAGES

    Brown, M. Alex; Wardle, Kent E.; Lumetta, Gregg; ...

    2016-01-01

    The major components of the modified ALSEP process have been demonstrated on a modified 2-cm annular centrifugal contactor with an enhanced mixing zone using stable fission products and radiotracers. The results show that by decreasing the pH of the minor actinide stripping solution, using HEDTA instead of DTPA, and increasing contact time, the process is very effective in separating americium from the lanthanides and the fission products.

  9. POST-PROCESSING ANALYSIS FOR THC SEEPAGE

    SciTech Connect

    Y. SUN

    2004-09-29

    This report describes the selection of water compositions for the total system performance assessment (TSPA) model of results from the thermal-hydrological-chemical (THC) seepage model documented in ''Drift-Scale THC Seepage Model'' (BSC 2004 [DIRS 169856]). The selection has been conducted in accordance with ''Technical Work Plan for: Near-Field Environment and Transport: Coupled Processes (Mountain-Scale TH/THC/THM, Drift-Scale THC Seepage, and Post-Processing Analysis for THC Seepage) Report Integration'' (BSC 2004 [DIRS 171334]). This technical work plan (TWP) was prepared in accordance with AP-2.27Q, ''Planning for Science Activities''. Section 1.2.3 of the TWP describes planning information pertaining to the technical scope, content, and management of this report. The post-processing analysis for THC seepage (THC-PPA) documented in this report provides a methodology for evaluating the near-field compositions of water and gas around a typical waste emplacement drift as these relate to the chemistry of seepage, if any, into the drift. The THC-PPA inherits the conceptual basis of the THC seepage model, but is an independently developed process. The relationship between the post-processing analysis and other closely related models, together with their main functions in providing seepage chemistry information for the Total System Performance Assessment for the License Application (TSPA-LA), are illustrated in Figure 1-1. The THC-PPA provides a data selection concept and direct input to the physical and chemical environment (P&CE) report that supports the TSPA model. The purpose of the THC-PPA is further discussed in Section 1.2. The data selection methodology of the post-processing analysis (Section 6.2.1) was initially applied to results of the THC seepage model as presented in ''Drift-Scale THC Seepage Model'' (BSC 2004 [DIRS 169856]). Other outputs from the THC seepage model (DTN: LB0302DSCPTHCS.002 [DIRS 161976]) used in the P&CE (BSC 2004 [DIRS 169860

  10. 3D-HIM: A 3D High-density Interleaved Memory for Bipolar RRAM Design

    DTIC Science & Technology

    2013-05-01

    JOURNAL ARTICLE (Post Print ) 3. DATES COVERED (From - To) DEC 2010 – NOV 2012 4. TITLE AND SUBTITLE 3D -HIM: A 3D HIGH-DENSITY INTERLEAVED MEMORY...emerged as one of the promising candidates for large data storage in computing systems. Moreover, building up RRAM in a three dimensional ( 3D ) stacking...brings in the potential reliability issue. To alleviate the situation, we introduce two novel 3D stacking structures built upon bipolar RRAM

  11. Novel fabrication process for 3D meander-shaped microcoils in SU-8 dielectric and their application to linear micromotors

    NASA Astrophysics Data System (ADS)

    Seidemann, Volker; Buettgenbach, Stephanus

    2001-04-01

    This paper reports on an optimized fabrication process for three dimensional coil structures such as meander or helical coils wound around in plane magnetic structures. The process consists of UV depth lithography employing AZ4562 and SU8 photo resists and electroplating of copper and nickel-iron. Furthermore SU8 is used as the embedding dielectric due to its excellent planarization properties and high structural aspect ratio. Special emphasis was laid on the decrease of via interconnect resistance by electroplating the vias and upper conductors in a single step thus avoiding a large number of resistive interfaces. This was achieved by sacrificial wiring and structured seed layers. The developed technology is applied to a variable reluctance micro motor with a novel design that avoids high friction. The presented concept makes use of a stator traveler configuration generating complementary attraction forces. The technology and design concept is presented and first results are demonstrated.

  12. Laser processing of thin-film multilayer structures: comparison between a 3D thermal model and experimental results.

    PubMed

    Naghshine, Babak B; Kiani, Amirkianoosh

    2017-01-01

    In this research, a numerical model is introduced for simulation of laser processing of thin film multilayer structures, to predict the temperature and ablated area for a set of laser parameters including average power and repetition rate. Different thin-films on Si substrate were processed by nanosecond Nd:YAG laser pulses and the experimental and numerical results were compared to each other. The results show that applying a thin film on the surface can completely change the temperature field and vary the shape of the heat affected zone. The findings of this paper can have many potential applications including patterning the cell growth for biomedical applications and controlling the grain size in fabrication of polycrystalline silicon (poly-Si) thin-film transistors (TFTs).

  13. Quantitative fractography by digital image processing: NIH Image macro tools for stereo pair analysis and 3-D reconstruction.

    PubMed

    Hein, L R

    2001-10-01

    A set of NIH Image macro programs was developed to make qualitative and quantitative analyses from digital stereo pictures produced by scanning electron microscopes. These tools were designed for image alignment, anaglyph representation, animation, reconstruction of true elevation surfaces, reconstruction of elevation profiles, true-scale elevation mapping and, for the quantitative approach, surface area and roughness calculations. Limitations on time processing, scanning techniques and programming concepts are also discussed.

  14. Databases post-processing in Tensoral

    NASA Technical Reports Server (NTRS)

    Dresselhaus, Eliot

    1994-01-01

    The Center for Turbulent Research (CTR) post-processing effort aims to make turbulence simulations and data more readily and usefully available to the research and industrial communities. The Tensoral language, introduced in this document and currently existing in prototype form, is the foundation of this effort. Tensoral provides a convenient and powerful protocol to connect users who wish to analyze fluids databases with the authors who generate them. In this document we introduce Tensoral and its prototype implementation in the form of a user's guide. This guide focuses on use of Tensoral for post-processing turbulence databases. The corresponding document - the Tensoral 'author's guide' - which focuses on how authors can make databases available to users via the Tensoral system - is currently unwritten. Section 1 of this user's guide defines Tensoral's basic notions: we explain the class of problems at hand and how Tensoral abstracts them. Section 2 defines Tensoral syntax for mathematical expressions. Section 3 shows how these expressions make up Tensoral statements. Section 4 shows how Tensoral statements and expressions are embedded into other computer languages (such as C or Vectoral) to make Tensoral programs. We conclude with a complete example program.

  15. New Navigation Post-Processing Tools for Oceanographic Submersibles

    NASA Astrophysics Data System (ADS)

    Kinsey, J. C.; Whitcomb, L. L.; Yoerger, D. R.; Howland, J. C.; Ferrini, V. L.; Hegrenas, O.

    2006-12-01

    We report the development of Navproc, a new set of software tools for post-processing oceanographic submersible navigation data that exploits previously reported improvements in navigation sensing and estimation (e.g. Eos Trans. AGU, 84(46), Fall Meet. Suppl., Abstract OS32A- 0225, 2003). The development of these tools is motivated by the need to have post-processing software that allows users to compensate for errors in vehicle navigation, recompute the vehicle position, and then save the results for use with quantitative science data (e.g. bathymetric sonar data) obtained during the mission. Navproc does not provide real-time navigation or display of data nor is it capable of high-resolution, three dimensional (3D) data display. Navproc supports the ASCII data formats employed by the vehicles of the National Deep Submergence Facility (NDSF) operated by the Woods Hole Oceanographic Institution (WHOI). Post-processing of navigation data with Navproc is comprised of three tasks. First, data is converted from the logged ASCII file to a binary Matlab file. When loaded into Matlab, each sensor has a data structure containing the time stamped data sampled at the native update rate of the sensor. An additional structure contains the real-time vehicle navigation data. Second, the data can be displayed using a Graphical User Interface (GUI), allowing users to visually inspect the quality of the data and graphically extract portions of the data. Third, users can compensate for errors in the real-time vehicle navigation. Corrections include: (i) manual filtering and median filtering of long baseline (LBL) ranges; (ii) estimation of the Doppler/gyro alignment using previously reported methodologies; and (iii) sound velocity, tide, and LBL transponder corrections. Using these corrections, the Doppler and LBL positions can be recomputed to provide improved estimates of the vehicle position compared to those computed in real-time. The data can be saved in either binary or ASCII

  16. 4D flow mri post-processing strategies for neuropathologies

    NASA Astrophysics Data System (ADS)

    Schrauben, Eric Mathew

    4D flow MRI allows for the measurement of a dynamic 3D velocity vector field. Blood flow velocities in large vascular territories can be qualitatively visualized with the added benefit of quantitative probing. Within cranial pathologies theorized to have vascular-based contributions or effects, 4D flow MRI provides a unique platform for comprehensive assessment of hemodynamic parameters. Targeted blood flow derived measurements, such as flow rate, pulsatility, retrograde flow, or wall shear stress may provide insight into the onset or characterization of more complex neuropathologies. Therefore, the thorough assessment of each parameter within the context of a given disease has important medical implications. Not surprisingly, the last decade has seen rapid growth in the use of 4D flow MRI. Data acquisition sequences are available to researchers on all major scanner platforms. However, the use has been limited mostly to small research trials. One major reason that has hindered the more widespread use and application in larger clinical trials is the complexity of the post-processing tasks and the lack of adequate tools for these tasks. Post-processing of 4D flow MRI must be semi-automated, fast, user-independent, robust, and reliably consistent for use in a clinical setting, within large patient studies, or across a multicenter trial. Development of proper post-processing methods coupled with systematic investigation in normal and patient populations pushes 4D flow MRI closer to clinical realization while elucidating potential underlying neuropathological origins. Within this framework, the work in this thesis assesses venous flow reproducibility and internal consistency in a healthy population. A preliminary analysis of venous flow parameters in healthy controls and multiple sclerosis patients is performed in a large study employing 4D flow MRI. These studies are performed in the context of the chronic cerebrospinal venous insufficiency hypothesis. Additionally, a

  17. What's the Point of a Raster ? Advantages of 3D Point Cloud Processing over Raster Based Methods for Accurate Geomorphic Analysis of High Resolution Topography.

    NASA Astrophysics Data System (ADS)

    Lague, D.

    2014-12-01

    High Resolution Topographic (HRT) datasets are predominantly stored and analyzed as 2D raster grids of elevations (i.e., Digital Elevation Models). Raster grid processing is common in GIS software and benefits from a large library of fast algorithms dedicated to geometrical analysis, drainage network computation and topographic change measurement. Yet, all instruments or methods currently generating HRT datasets (e.g., ALS, TLS, SFM, stereo satellite imagery) output natively 3D unstructured point clouds that are (i) non-regularly sampled, (ii) incomplete (e.g., submerged parts of river channels are rarely measured), and (iii) include 3D elements (e.g., vegetation, vertical features such as river banks or cliffs) that cannot be accurately described in a DEM. Interpolating the raw point cloud onto a 2D grid generally results in a loss of position accuracy, spatial resolution and in more or less controlled interpolation. Here I demonstrate how studying earth surface topography and processes directly on native 3D point cloud datasets offers several advantages over raster based methods: point cloud methods preserve the accuracy of the original data, can better handle the evaluation of uncertainty associated to topographic change measurements and are more suitable to study vegetation characteristics and steep features of the landscape. In this presentation, I will illustrate and compare Point Cloud based and Raster based workflows with various examples involving ALS, TLS and SFM for the analysis of bank erosion processes in bedrock and alluvial rivers, rockfall statistics (including rockfall volume estimate directly from point clouds) and the interaction of vegetation/hydraulics and sedimentation in salt marshes. These workflows use 2 recently published algorithms for point cloud classification (CANUPO) and point cloud comparison (M3C2) now implemented in the open source software CloudCompare.

  18. 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.

  19. Evaluating the Credibility of Transport Processes in the Global Modeling Initiative 3D Model Simulations of Ozone Recovery

    NASA Technical Reports Server (NTRS)

    Strahan, Susan E.; Douglass, Anne R.

    2003-01-01

    The Global Modeling Initiative has integrated two 35-year simulations of an ozone recovery scenario with an offline chemistry and transport model using two different meteorological inputs. Physically based diagnostics, derived from satellite and aircraft data sets, are described and then used to evaluate the realism of temperature and transport processes in the simulations. Processes evaluated include barrier formation in the subtropics and polar regions, and extratropical wave-driven transport. Some diagnostics are especially relevant to simulation of lower stratospheric ozone, but most are applicable to any stratospheric simulation. The temperature evaluation, which is relevant to gas phase chemical reactions, showed that both sets of meteorological fields have near climatological values at all latitudes and seasons at 30 hPa and below. Both simulations showed weakness in upper stratospheric wave driving. The simulation using input from a general circulation model (GMI(sub GCM)) showed a very good residual circulation in the tropics and northern hemisphere. The simulation with input from a data assimilation system (GMI(sub DAS)) performed better in the midlatitudes than at high latitudes. Neither simulation forms a realistic barrier at the vortex edge, leading to uncertainty in the fate of ozone-depleted vortex air. Overall, tracer transport in the offline GMI(sub GCM) has greater fidelity throughout the stratosphere than the GMI(sub DAS).

  20. 3D-liquid chromatography as a complex mixture characterization tool for knowledge-based downstream process development.

    PubMed

    Hanke, Alexander T; Tsintavi, Eleni; Ramirez Vazquez, Maria Del Pilar; van der Wielen, Luuk A M; Verhaert, Peter D E M; Eppink, Michel H M; van de Sandt, Emile J A X; Ottens, Marcel

    2016-09-01

    Knowledge-based development of chromatographic separation processes requires efficient techniques to determine the physicochemical properties of the product and the impurities to be removed. These characterization techniques are usually divided into approaches that determine molecular properties, such as charge, hydrophobicity and size, or molecular interactions with auxiliary materials, commonly in the form of adsorption isotherms. In this study we demonstrate the application of a three-dimensional liquid chromatography approach to a clarified cell homogenate containing a therapeutic enzyme. Each separation dimension determines a molecular property relevant to the chromatographic behavior of each component. Matching of the peaks across the different separation dimensions and against a high-resolution reference chromatogram allows to assign the determined parameters to pseudo-components, allowing to determine the most promising technique for the removal of each impurity. More detailed process design using mechanistic models requires isotherm parameters. For this purpose, the second dimension consists of multiple linear gradient separations on columns in a high-throughput screening compatible format, that allow regression of isotherm parameters with an average standard error of 8%. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1283-1291, 2016. © 2016 American Institute of Chemical Engineers.

  1. A high performance biometric signal and image processing method to reveal blood perfusion towards 3D oxygen saturation mapping

    NASA Astrophysics Data System (ADS)

    Imms, Ryan; Hu, Sijung; Azorin-Peris, Vicente; Trico, Michaël.; Summers, Ron

    2014-03-01

    Non-contact imaging photoplethysmography (PPG) is a recent development in the field of physiological data acquisition, currently undergoing a large amount of research to characterize and define the range of its capabilities. Contact-based PPG techniques have been broadly used in clinical scenarios for a number of years to obtain direct information about the degree of oxygen saturation for patients. With the advent of imaging techniques, there is strong potential to enable access to additional information such as multi-dimensional blood perfusion and saturation mapping. The further development of effective opto-physiological monitoring techniques is dependent upon novel modelling techniques coupled with improved sensor design and effective signal processing methodologies. The biometric signal and imaging processing platform (bSIPP) provides a comprehensive set of features for extraction and analysis of recorded iPPG data, enabling direct comparison with other biomedical diagnostic tools such as ECG and EEG. Additionally, utilizing information about the nature of tissue structure has enabled the generation of an engineering model describing the behaviour of light during its travel through the biological tissue. This enables the estimation of the relative oxygen saturation and blood perfusion in different layers of the tissue to be calculated, which has the potential to be a useful diagnostic tool.

  2. 3D digital image processing for biofilm quantification from confocal laser scanning microscopy: Multidimensional statistical analysis of biofilm modeling

    NASA Astrophysics Data System (ADS)

    Zielinski, Jerzy S.

    The dramatic increase in number and volume of digital images produced in medical diagnostics, and the escalating demand for rapid access to these relevant medical data, along with the need for interpretation and retrieval has become of paramount importance to a modern healthcare system. Therefore, there is an ever growing need for processed, interpreted and saved images of various types. Due to the high cost and unreliability of human-dependent image analysis, it is necessary to develop an automated method for feature extraction, using sophisticated mathematical algorithms and reasoning. This work is focused on digital image signal processing of biological and biomedical data in one- two- and three-dimensional space. Methods and algorithms presented in this work were used to acquire data from genomic sequences, breast cancer, and biofilm images. One-dimensional analysis was applied to DNA sequences which were presented as a non-stationary sequence and modeled by a time-dependent autoregressive moving average (TD-ARMA) model. Two-dimensional analyses used 2D-ARMA model and applied it to detect breast cancer from x-ray mammograms or ultrasound images. Three-dimensional detection and classification techniques were applied to biofilm images acquired using confocal laser scanning microscopy. Modern medical images are geometrically arranged arrays of data. The broadening scope of imaging as a way to organize our observations of the biophysical world has led to a dramatic increase in our ability to apply new processing techniques and to combine multiple channels of data into sophisticated and complex mathematical models of physiological function and dysfunction. With explosion of the amount of data produced in a field of biomedicine, it is crucial to be able to construct accurate mathematical models of the data at hand. Two main purposes of signal modeling are: data size conservation and parameter extraction. Specifically, in biomedical imaging we have four key problems

  3. 3D Printing and Its Urologic Applications

    PubMed Central

    Soliman, Youssef; Feibus, Allison H; Baum, Neil

    2015-01-01

    3D printing is the development of 3D objects via an additive process in which successive layers of material are applied under computer control. This article discusses 3D printing, with an emphasis on its historical context and its potential use in the field of urology. PMID:26028997

  4. A Sparsity-Based Approach to 3D Binaural Sound Synthesis Using Time-Frequency Array Processing

    NASA Astrophysics Data System (ADS)

    Cobos, Maximo; Lopez, JoseJ; Spors, Sascha

    2010-12-01

    Localization of sounds in physical space plays a very important role in multiple audio-related disciplines, such as music, telecommunications, and audiovisual productions. Binaural recording is the most commonly used method to provide an immersive sound experience by means of headphone reproduction. However, it requires a very specific recording setup using high-fidelity microphones mounted in a dummy head. In this paper, we present a novel processing framework for binaural sound recording and reproduction that avoids the use of dummy heads, which is specially suitable for immersive teleconferencing applications. The method is based on a time-frequency analysis of the spatial properties of the sound picked up by a simple tetrahedral microphone array, assuming source sparseness. The experiments carried out using simulations and a real-time prototype confirm the validity of the proposed approach.

  5. RAPID COMMUNICATION: Processing of single domain Y Ba Cu O with pre-defined 3D interconnected porosity for bulk reinforcement

    NASA Astrophysics Data System (ADS)

    Sudhakar Reddy, E.; Babu, N. Hari; Shi, Y.; Cardwell, D. A.; Schmitz, G. J.

    2003-11-01

    A simple method for processing large, single domain Y-Ba-Cu-O (YBCO) bulks containing pre-defined 3D interconnected porosity is reported. The process involves the preparation of solid Y2BaCuO5 (Y-211) pre-form bodies by casting a water-based slurry into a mould containing a 3D wax model. The cast, composite sample is dried and heated to 600 °C to burn out organic binders and remove the wax component. The resulting Y-211 green body is then sintered at 1080 °C to produce a self-supporting ceramic sample containing an interconnected porous structure that replicates the initial wax model. Finally, the porous Y-211 body is transformed into near net shaped single domain YBa2Cu3O7-dgr (Y-123) by a seeded infiltration and growth processing technique and oxygenated to produce a superconducting sample. The as-produced, porous single YBCO domains can be reinforced with resins or alloys for improved mechanical and thermal properties.

  6. Visualizing 3D/4D Environmental Big Data Using Many-core Compute Unified Device Architecture (CUDA) and Multi-core Central Processing Unit (CPUs)

    NASA Astrophysics Data System (ADS)

    Li, J.; Jiang, Y.; Yang, C.; Huang, Q.

    2012-12-01

    Visualizing 3D/4D environmental Big Data is critical to understand and predict environmental phenomena for relevant decision making. This research explores how to best utilize Graphics Process Units (GPUs) and Central Processing Units (CPUs) collaboratively to speed up the visualization process. Taking the visualization of dust storm as an example, we developed a systematic visualization framework. To compare the potential speedup of using GPUs versus that of using CPUs, we implemented visualization components based on both multi-core CPUs and many-core GPUs. We found that 1) multi-core CPUs and many-core GPUs can improve the efficiency of mathematical calculations and graphics rendering using multithreading techniques; 2) when increasing the size of blocks of GPUs for reprojecting, interpolating and rendering the same data, the executing time drops consistently before reaching a peak.; 3) GPU-based implementations is faster than CPU-based implementations. However, the best performance of rendering with GPUs is very close to that with CPUs. Therefore, visualization of 3D/4D environmental data using GPUs is a better solution than that of using CPUs.

  7. 3D Plasmon Ruler

    SciTech Connect

    2011-01-01

    In this animation of a 3D plasmon ruler, the plasmonic assembly acts as a transducer to deliver optical information about the structural dynamics of an attached protein. (courtesy of Paul Alivisatos group)

  8. Prominent Rocks - 3-D

    NASA Image and Video Library

    1997-07-13

    Many prominent rocks near the Sagan Memorial Station are featured in this image from NASA Mars Pathfinder. Shark, Half-Dome, and Pumpkin are at center 3D glasses are necessary to identify surface detail.

  9. 3D Laser System

    NASA Image and Video Library

    2015-09-16

    NASA Glenn's Icing Research Tunnel 3D Laser System used for digitizing ice shapes created in the wind tunnel. The ice shapes are later utilized for characterization, analysis, and software development.

  10. Intraoral 3D scanner

    NASA Astrophysics Data System (ADS)

    Kühmstedt, Peter; Bräuer-Burchardt, Christian; Munkelt, Christoph; Heinze, Matthias; Palme, Martin; Schmidt, Ingo; Hintersehr, Josef; Notni, Gunther

    2007-09-01

    Here a new set-up of a 3D-scanning system for CAD/CAM in dental industry is proposed. The system is designed for direct scanning of the dental preparations within the mouth. The measuring process is based on phase correlation technique in combination with fast fringe projection in a stereo arrangement. The novelty in the approach is characterized by the following features: A phase correlation between the phase values of the images of two cameras is used for the co-ordinate calculation. This works contrary to the usage of only phase values (phasogrammetry) or classical triangulation (phase values and camera image co-ordinate values) for the determination of the co-ordinates. The main advantage of the method is that the absolute value of the phase at each point does not directly determine the coordinate. Thus errors in the determination of the co-ordinates are prevented. Furthermore, using the epipolar geometry of the stereo-like arrangement the phase unwrapping problem of fringe analysis can be solved. The endoscope like measurement system contains one projection and two camera channels for illumination and observation of the object, respectively. The new system has a measurement field of nearly 25mm × 15mm. The user can measure two or three teeth at one time. So the system can by used for scanning of single tooth up to bridges preparations. In the paper the first realization of the intraoral scanner is described.

  11. Microfabricating 3D Structures by Laser Origami

    DTIC Science & Technology

    2011-11-09

    10.1117/2.1201111.003952 Microfabricating 3D structures by laser origami Alberto Piqué, Scott Mathews, Andrew Birnbaum, and Nicholas Charipar A new...folding known as origami allows the transformation of flat patterns into 3D shapes. A similar approach can be used to generate 3D structures com...materials Figure 1. (A–C) Schematic illustrating the steps in the laser origami process and (D) a resulting folded out-of-plane 3D structure. that can

  12. AE3D

    SciTech Connect

    Spong, Donald A

    2016-06-20

    AE3D solves for the shear Alfven eigenmodes and eigenfrequencies in a torodal magnetic fusion confinement device. The configuration can be either 2D (e.g. tokamak, reversed field pinch) or 3D (e.g. stellarator, helical reversed field pinch, tokamak with ripple). The equations solved are based on a reduced MHD model and sound wave coupling effects are not currently included.

  13. Data Processing Methods for 3D Seismic Imaging of Subsurface Volcanoes: Applications to the Tarim Flood Basalt.

    PubMed

    Wang, Lei; Tian, Wei; Shi, Yongmin

    2017-08-07

    The morphology and structure of plumbing systems can provide key information on the eruption rate and style of basalt lava fields. The most powerful way to study subsurface geo-bodies is to use industrial 3D reflection seismological imaging. However, strategies to image subsurface volcanoes are very different from that of oil and gas reservoirs. In this study, we process seismic data cubes from the Northern Tarim Basin, China, to illustrate how to visualize sills through opacity rendering techniques and how to image the conduits by time-slicing. In the first case, we isolated probes by the seismic horizons marking the contacts between sills and encasing strata, applying opacity rendering techniques to extract sills from the seismic cube. The resulting detailed sill morphology shows that the flow direction is from the dome center to the rim. In the second seismic cube, we use time-slices to image the conduits, which corresponds to marked discontinuities within the encasing rocks. A set of time-slices obtained at different depths show that the Tarim flood basalts erupted from central volcanoes, fed by separate pipe-like conduits.

  14. 3D Imaging of Porous Media Using Laser Scanning Confocal Microscopy with Application to Microscale Transport Processes

    SciTech Connect

    Fredrich, J.T.

    1999-02-10

    We present advances in the application of laser scanning confocal microscopy (LSCM) to image, reconstruct, and characterize statistically the microgeometry of porous geologic and engineering materials. We discuss technical and practical aspects of this imaging technique, including both its advantages and limitations. Confocal imaging can be used to optically section a material, with sub-micron resolution possible in the lateral and axial planes. The resultant volumetric image data, consisting of fluorescence intensities for typically {approximately}50 million voxels in XYZ space, can be used to reconstruct the three-dimensional structure of the two-phase medium. We present several examples of this application, including studying pore geometry in sandstone, characterizing brittle failure processes in low-porosity rock deformed under triaxial loading conditions in the laboratory, and analyzing the microstructure of porous ceramic insulations. We then describe approaches to extract statistical microgeometric descriptions from volumetric image data, and present results derived from confocal volumetric data sets. Finally, we develop the use of confocal image data to automatically generate a three-dimensional mesh for numerical pore-scale flow simulations.

  15. Incorporating 3-D Subsurface Hydrologic Processes within the Community Land Surface Model (CLM): Coupling PFLOTRAN and CLM

    NASA Astrophysics Data System (ADS)

    Bisht, G.; Mills, R. T.; Hoffman, F. M.; Thornton, P. E.; Lichtner, P. C.; Hammond, G. E.

    2011-12-01

    Numerous studies have shown a positive soil moisture-rainfall feedback through observational data, as well as, modeling studies. Spatial variability of topography, soils, and vegetation play a significant role in determining the response of land surface states (soil moisture) and fluxes (runoff, evapotranspirtiaon); but their explicit accounting within Land Surface Models (LSMs) is computa- tionally expensive. Additionally, anthropogenic climate change is altering the hydrologic cycle at global and regional scales. Characterizing the sensitivity of groundwater recharge is critical for understanding the effects of climate change on water resources. In order to explicitly represent lateral redistribution of soil moisture and unified treatment of the unsaturated-saturated zone in the subsurface within the CLM, we propose coupling PFLOTRAN and CLM. PFLOTRAN is a parallel multiphase-multicomponent subsurface reactive flow and transport code for modeling subsurface processes and has been devel- oped under a DOE SciDAC-2 project. PFLOTRAN is written in Fortran 90 using a modular, object-oriented approach. PFLOTRAN utilizes fully implicit time-stepping and is built on top of the Portable, Extensible Toolkit for Scientific Computation (PETSc). The PFLOTRAN model is capable of simulating fluid flow through porous media with fluid phases of air, water, and supercritical CO2. PFLOTRAN has been successfully employed on up to 131,072 cores on Jaguar, the massively parallel Cray XT4/XT5 at ORNL, for problems composed of up to 2 billion degrees of freedom. In this work, we will present a strategy of coupling the two models, CLM and PFLOTRAN, along with a few preliminary results obtained from the coupled model.

  16. 3D bone tissue growth in hollow fibre membrane bioreactor: implications of various process parameters on tissue nutrition.

    PubMed

    Abdullah, N S; Das, D B; Ye, H; Cui, Z F

    2006-09-01

    New experimental evidence shows that hollow fibre membrane bioreactor (HFMB) may be applied to grow bulky bone tissues which may then be implanted into patients to repair skeletal defects. To design effective bone tissue engineering protocols, it is necessary to determine the quantitative relationships between the cell environment and tissue behaviour in HFMBs and their relationship with nutrient supply. It is also necessary to determine under what conditions nutritional limitations may occur and, hence, may cause cell death. These require that the appropriate bioreactor conditions for generating neotissues, and the nutrient transfer behaviour and chemical reaction during cell growth and extracellular matrix