Science.gov

Sample records for accurate three-dimensional 3-d

  1. TRIM—3D: a three-dimensional model for accurate simulation of shallow water flow

    USGS Publications Warehouse

    Casulli, Vincenzo; Bertolazzi, Enrico; Cheng, Ralph T.

    1993-01-01

    A semi-implicit finite difference formulation for the numerical solution of three-dimensional tidal circulation is discussed. The governing equations are the three-dimensional Reynolds equations in which the pressure is assumed to be hydrostatic. A minimal degree of implicitness has been introduced in the finite difference formula so that the resulting algorithm permits the use of large time steps at a minimal computational cost. This formulation includes the simulation of flooding and drying of tidal flats, and is fully vectorizable for an efficient implementation on modern vector computers. The high computational efficiency of this method has made it possible to provide the fine details of circulation structure in complex regions that previous studies were unable to obtain. For proper interpretation of the model results suitable interactive graphics is also an essential tool.

  2. Three-Dimensional (3D) Distribution

    DTIC Science & Technology

    2009-03-11

    witnessed by ongoing efforts in both Afghanistan and Iraq , must turn distribution challenges into opportunities by mastering Three-Dimensional (3D...sustainment. 5 Joint Logistics Functions •Supply •Services •Maintenance •Transportation • Health Service Support •General Engineering Joint Personnel...Maintenance •Transportation • Health Service Support •Explosive Ordinance Disposal •Human Resource Support •Legal Support •Religious Support •Financial

  3. PLOT3D- DRAWING THREE DIMENSIONAL SURFACES

    NASA Technical Reports Server (NTRS)

    Canright, R. B.

    1994-01-01

    PLOT3D is a package of programs to draw three-dimensional surfaces of the form z = f(x,y). The function f and the boundary values for x and y are the input to PLOT3D. The surface thus defined may be drawn after arbitrary rotations. However, it is designed to draw only functions in rectangular coordinates expressed explicitly in the above form. It cannot, for example, draw a sphere. Output is by off-line incremental plotter or online microfilm recorder. This package, unlike other packages, will plot any function of the form z = f(x,y) and portrays continuous and bounded functions of two independent variables. With curve fitting; however, it can draw experimental data and pictures which cannot be expressed in the above form. The method used is division into a uniform rectangular grid of the given x and y ranges. The values of the supplied function at the grid points (x, y) are calculated and stored; this defines the surface. The surface is portrayed by connecting successive (y,z) points with straight-line segments for each x value on the grid and, in turn, connecting successive (x,z) points for each fixed y value on the grid. These lines are then projected by parallel projection onto the fixed yz-plane for plotting. This program has been implemented on the IBM 360/67 with on-line CDC microfilm recorder.

  4. Development of three-dimensional memory (3D-M)

    NASA Astrophysics Data System (ADS)

    Yu, Hong-Yu; Shen, Chen; Jiang, Lingli; Dong, Bin; Zhang, Guobiao

    2016-10-01

    Since the invention of 3-D ROM in 1996, three-dimensional memory (3D-M) has been under development for nearly two decades. In this presentation, we'll review the 3D-M history and compare different 3D-Ms (including 3D-OTP from Matrix Semiconductor, 3D-NAND from Samsung and 3D-XPoint from Intel/Micron).

  5. 3D object hiding using three-dimensional ptychography

    NASA Astrophysics Data System (ADS)

    Zhang, Jun; Wang, Zhibo; Li, Tuo; Pan, An; Wang, Yali; Shi, Yishi

    2016-09-01

    We present a novel technique for 3D object hiding by applying three-dimensional ptychography. Compared with 3D information hiding based on holography, the proposed ptychography-based hiding technique is easier to implement, because the reference beam and high-precision interferometric optical setup are not required. The acquisition of the 3D object and the ptychographic encoding process are performed optically. Owing to the introduction of probe keys, the security of the ptychography-based hiding system is significantly enhanced. A series of experiments and simulations demonstrate the feasibility and imperceptibility of the proposed method.

  6. S2PLOT: Three-dimensional (3D) Plotting Library

    NASA Astrophysics Data System (ADS)

    Barnes, D. G.; Fluke, C. J.; Bourke, P. D.; Parry, O. T.

    2011-03-01

    We present a new, three-dimensional (3D) plotting library with advanced features, and support for standard and enhanced display devices. The library - S2PLOT - is written in C and can be used by C, C++ and FORTRAN programs on GNU/Linux and Apple/OSX systems. S2PLOT draws objects in a 3D (x,y,z) Cartesian space and the user interactively controls how this space is rendered at run time. With a PGPLOT inspired interface, S2PLOT provides astronomers with elegant techniques for displaying and exploring 3D data sets directly from their program code, and the potential to use stereoscopic and dome display devices. The S2PLOT architecture supports dynamic geometry and can be used to plot time-evolving data sets, such as might be produced by simulation codes. In this paper, we introduce S2PLOT to the astronomical community, describe its potential applications, and present some example uses of the library.

  7. Three-Dimensional (3D) Additive Construction: Printing with Regolith

    NASA Technical Reports Server (NTRS)

    Tsoras, Alexandra

    2013-01-01

    Three dimensional (3D) printing is a new and booming topic in many realms of research and engineering technology. When it comes to space science and aerospace engineering, it can be useful in numerous ways. As humans travel deeper into space and farther from Earth, sending large quantities of needed supplies from Earth for a mission becomes astronomically expensive and less plausible. In order to reach further to new places, In Situ Resource Utilization (ISRU), a project that pushes for technologies to use materials already present in the destination's environment, is necessary. By using materials already available in space such as regolith from the Moon, Mars, or an asteroid's surface, fewer materials need to be brought into space on a launched vehicle. This allows a vehicle to be filled with more necessary supplies for a deep space mission that may not be found in space, like food and fuel. This project's main objective was to develop a 3D printer that uses regolith to "print" large structures, such as a dome, to be used as a heat shield upon a vehicle's reentry into the atmosphere or even a habitat. 3D printing is a growing technology that uses many different methods to mix, heat, and mold a material into a specific shape. In order to heat the regolith enough to stick together into a solid shape, it must be sintered at each layer of material that is laid. Sintering is a process that heats and compresses a powdered material until it fuses into a solid, which requires a lot of energy input. As an alternative, a polymer can be mixed with the regolith before or as it is sent to the 3D printer head to be placed in the specific shape. The addition of the polymer, which melts and binds at much lower temperatures than sintering temperatures, greatly decreases the required heating temperature and energy input. The main task of the project was to identify a functional material for the printer. The first step was to find a miscible. polymer/solvent solution. This solution

  8. Accurate three-dimensional documentation of distinct sites

    NASA Astrophysics Data System (ADS)

    Singh, Mahesh K.; Dutta, Ashish; Subramanian, Venkatesh K.

    2017-01-01

    One of the most critical aspects of documenting distinct sites is acquiring detailed and accurate range information. Several three-dimensional (3-D) acquisition techniques are available, but each has its own limitations. This paper presents a range data fusion method with the aim to enhance the descriptive contents of the entire 3-D reconstructed model. A kernel function is introduced for supervised classification of the range data using a kernelized support vector machine. The classification method is based on the local saliency features of the acquired range data. The range data acquired from heterogeneous range sensors are transformed into a defined common reference frame. Based on the segmentation criterion, the fusion of range data is performed by integrating finer regions of range data acquired from a laser range scanner with the coarser region of Kinect's range data. After fusion, the Delaunay triangulation algorithm is applied to generate the highly accurate, realistic 3-D model of the scene. Finally, experimental results show the robustness of the proposed approach.

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

    NASA Technical Reports Server (NTRS)

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

    1993-01-01

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

  10. Three-dimensional (3D) printed endovascular simulation models: a feasibility study

    PubMed Central

    Nesbitt, Craig; McCaslin, James; Bagnall, Alan; Davey, Philip; Bose, Pentop; Williams, Rob

    2017-01-01

    Background Three-dimensional (3D) printing is a manufacturing process in which an object is created by specialist printers designed to print in additive layers to create a 3D object. Whilst there are initial promising medical applications of 3D printing, a lack of evidence to support its use remains a barrier for larger scale adoption into clinical practice. Endovascular virtual reality (VR) simulation plays an important role in the safe training of future endovascular practitioners, but existing VR models have disadvantages including cost and accessibility which could be addressed with 3D printing. Methods This study sought to evaluate the feasibility of 3D printing an anatomically accurate human aorta for the purposes of endovascular training. Results A 3D printed model was successfully designed and printed and used for endovascular simulation. The stages of development and practical applications are described. Feedback from 96 physicians who answered a series of questions using a 5 point Likert scale is presented. Conclusions Initial data supports the value of 3D printed endovascular models although further educational validation is required. PMID:28251121

  11. Three-dimensional (3D) shadowgraph technique visualizes thermal convection

    NASA Astrophysics Data System (ADS)

    Huang, Jinzi; Zhang, Jun; Physics; Maths Research Institutes, NYU Shanghai Team; Applied Maths Lab, NYU Team

    2016-11-01

    Shadowgraph technique has been widely used in thermal convection, and in other types of convection and advection processes in fluids. The technique reveals minute density differences in the fluid, which is otherwise transparent to the eyes and to light-sensitive devices. However, such technique normally integrates the fluid information along the depth of view and collapses the 3D density field onto a 2D plane. In this work, we introduce a stereoscopic shadowgraph technique that preserves the information of the fluid depth by using two cross-field shadowgraphs. The two shadowgraphs are coded with different and complementary colors, and each is seen by only one eye of the viewer. The two shadowgraphs can also be temporally modulated to achieve the same stereoscopic vision of the convective fluid. We further discuss ways to make use of this technique in order to extract useful information for research in fluids.

  12. The production of anatomical teaching resources using three-dimensional (3D) printing technology.

    PubMed

    McMenamin, Paul G; Quayle, Michelle R; McHenry, Colin R; Adams, Justin W

    2014-01-01

    The teaching of anatomy has consistently been the subject of societal controversy, especially in the context of employing cadaveric materials in professional medical and allied health professional training. The reduction in dissection-based teaching in medical and allied health professional training programs has been in part due to the financial considerations involved in maintaining bequest programs, accessing human cadavers and concerns with health and safety considerations for students and staff exposed to formalin-containing embalming fluids. This report details how additive manufacturing or three-dimensional (3D) printing allows the creation of reproductions of prosected human cadaver and other anatomical specimens that obviates many of the above issues. These 3D prints are high resolution, accurate color reproductions of prosections based on data acquired by surface scanning or CT imaging. The application of 3D printing to produce models of negative spaces, contrast CT radiographic data using segmentation software is illustrated. The accuracy of printed specimens is compared with original specimens. This alternative approach to producing anatomically accurate reproductions offers many advantages over plastination as it allows rapid production of multiple copies of any dissected specimen, at any size scale and should be suitable for any teaching facility in any country, thereby avoiding some of the cultural and ethical issues associated with cadaver specimens either in an embalmed or plastinated form.

  13. VSViewer3D: a tool for interactive data mining of three-dimensional virtual screening data.

    PubMed

    Diller, Kyle I; Diller, David J

    2014-12-22

    The VSviewer3D is a simple Java tool for visual exploration of three-dimensional (3D) virtual screening data. The VSviewer3D brings together the ability to explore numerical data, such as calculated properties and virtual screening scores, structure depiction, interactive topological and 3D similarity searching, and 3D visualization. By doing so the user is better able to quickly identify outliers, assess tractability of large numbers of compounds, visualize hits of interest, annotate hits, and mix and match interesting scaffolds. We demonstrate the utility of the VSviewer3D by describing a use case in a docking based virtual screen.

  14. Sub-micrometer-precision, three-dimensional (3D) hydrodynamic focusing via "microfluidic drifting".

    PubMed

    Nawaz, Ahmad Ahsan; Zhang, Xiangjun; Mao, Xiaole; Rufo, Joseph; Lin, Sz-Chin Steven; Guo, Feng; Zhao, Yanhui; Lapsley, Michael; Li, Peng; McCoy, J Philip; Levine, Stewart J; Huang, Tony Jun

    2014-01-21

    In this article, we demonstrate single-layered, "microfluidic drifting" based three-dimensional (3D) hydrodynamic focusing devices with particle/cell focal positioning approaching submicron precision along both lateral and vertical directions. By systematically optimizing channel geometries and sample/sheath flow rates, a series of "microfluidic drifting" based 3D hydrodynamic focusing devices with different curvature angles are designed and fabricated. Their performances are then evaluated using confocal microscopy, fast camera imaging, and side-view imaging techniques. Using a device with a curvature angle of 180°, we have achieved a standard deviation of ±0.45 μm in particle focal position and a coefficient of variation (CV) of 2.37% in flow cytometric measurements. To the best of our knowledge, this is the best CV that has been achieved using a microfluidic flow cytometry device. Moreover, the device showed the capability to distinguish 8 peaks when subjected to a stringent 8-peak rainbow calibration test, signifying the ability to perform sensitive, accurate tests similar to commercial flow cytometers. We have further tested and validated our device by detection of HEK-293 cells. With its advantages in simple fabrication (i.e., single-layered device), precise 3D hydrodynamic focusing (i.e., submicrometer precision along both lateral and vertical directions), and high detection resolution (i.e., low CV), our method could serve as an important basis for high-performance, mass-producible microfluidic flow cytometry.

  15. Three-dimensional (3D) printing of mouse primary hepatocytes to generate 3D hepatic structure

    PubMed Central

    Kim, Yohan; Kang, Kyojin; Jeong, Jaemin; Paik, Seung Sam; Kim, Ji Sook; Park, Su A; Kim, Wan Doo; Park, Jisun

    2017-01-01

    Purpose The major problem in producing artificial livers is that primary hepatocytes cannot be cultured for many days. Recently, 3-dimensional (3D) printing technology draws attention and this technology regarded as a useful tool for current cell biology. By using the 3D bio-printing, these problems can be resolved. Methods To generate 3D bio-printed structures (25 mm × 25 mm), cells-alginate constructs were fabricated by 3D bio-printing system. Mouse primary hepatocytes were isolated from the livers of 6–8 weeks old mice by a 2-step collagenase method. Samples of 4 × 107 hepatocytes with 80%–90% viability were printed with 3% alginate solution, and cultured with well-defined culture medium for primary hepatocytes. To confirm functional ability of hepatocytes cultured on 3D alginate scaffold, we conducted quantitative real-time polymerase chain reaction and immunofluorescence with hepatic marker genes. Results Isolated primary hepatocytes were printed with alginate. The 3D printed hepatocytes remained alive for 14 days. Gene expression levels of Albumin, HNF-4α and Foxa3 were gradually increased in the 3D structures. Immunofluorescence analysis showed that the primary hepatocytes produced hepatic-specific proteins over the same period of time. Conclusion Our research indicates that 3D bio-printing technique can be used for long-term culture of primary hepatocytes. It can therefore be used for drug screening and as a potential method of producing artificial livers. PMID:28203553

  16. The Current Role of Three-Dimensional (3D) Printing in Plastic Surgery.

    PubMed

    Kamali, Parisa; Dean, David; Skoracki, Roman; Koolen, Pieter G L; Paul, Marek A; Ibrahim, Ahmed M S; Lin, Samuel J

    2016-01-21

    Since the advent of three-dimensional (3D) printing in the 1980s, it is now possible to produce physical objects from digital files and create 3D objects by adding one layer at a time following a predetermined pattern. Due to the continued development of inexpensive and easy- to- use 3D printers and bioprinting, this technique has gained more momentum over time, especially in the field of medicine. This paper reviews the current and possible future application of 3D printing technology within the field of plastic and reconstructive surgery.

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

    SciTech Connect

    James Menart

    2013-06-07

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

  18. Large-scale three-dimensional measurement via combining 3D scanner and laser rangefinder.

    PubMed

    Shi, Jinlong; Sun, Zhengxing; Bai, Suqin

    2015-04-01

    This paper presents a three-dimensional (3D) measurement method of large-scale objects by integrating a 3D scanner and a laser rangefinder. The 3D scanner, used to perform partial section measurement, is fixed on a robotic arm which can slide on a guide rail. The laser rangefinder, used to compute poses of the 3D scanner, is rigidly connected to the 3D scanner. During large-scale measurement, after measuring a partial section, the 3D scanner is straightly moved forward along the guide rail to measure another section. Meanwhile, the poses of the 3D scanner are estimated according to its moved distance for different partial section alignments. The performance and effectiveness are evaluated by experiments.

  19. Review of three-dimensional (3D) surface imaging for oncoplastic, reconstructive and aesthetic breast surgery.

    PubMed

    O'Connell, Rachel L; Stevens, Roger J G; Harris, Paul A; Rusby, Jennifer E

    2015-08-01

    Three-dimensional surface imaging (3D-SI) is being marketed as a tool in aesthetic breast surgery. It has recently also been studied in the objective evaluation of cosmetic outcome of oncological procedures. The aim of this review is to summarise the use of 3D-SI in oncoplastic, reconstructive and aesthetic breast surgery. An extensive literature review was undertaken to identify published studies. Two reviewers independently screened all abstracts and selected relevant articles using specific inclusion criteria. Seventy two articles relating to 3D-SI for breast surgery were identified. These covered endpoints such as image acquisition, calculations and data obtainable, comparison of 3D and 2D imaging and clinical research applications of 3D-SI. The literature provides a favourable view of 3D-SI. However, evidence of its superiority over current methods of clinical decision making, surgical planning, communication and evaluation of outcome is required before it can be accepted into mainstream practice.

  20. Three-dimensional potential flows from functions of a 3D complex variable

    NASA Technical Reports Server (NTRS)

    Kelly, Patrick; Panton, Ronald L.; Martin, E. D.

    1990-01-01

    Potential, or ideal, flow velocities can be found from the gradient of an harmonic function. An ordinary complex valued analytic function can be written as the sum of two real valued functions, both of which are harmonic. Thus, 2D complex valued functions serve as a source of functions that describe two-dimensional potential flows. However, this use of complex variables has been limited to two-dimensions. Recently, a new system of three-dimensional complex variables has been developed at the NASA Ames Research Center. As a step toward application of this theory to the analysis of 3D potential flow, several functions of a three-dimensional complex variable have been investigated. The results for two such functions, the 3D exponential and 3D logarithm, are presented in this paper. Potential flows found from these functions are investigated. Important characteristics of these flows fields are noted.

  1. Applications of three-dimensional (3D) printing for microswimmers and bio-hybrid robotics.

    PubMed

    Stanton, M M; Trichet-Paredes, C; Sánchez, S

    2015-04-07

    This article will focus on recent reports that have applied three-dimensional (3D) printing for designing millimeter to micrometer architecture for robotic motility. The utilization of 3D printing has rapidly grown in applications for medical prosthetics and scaffolds for organs and tissue, but more recently has been implemented for designing mobile robotics. With an increase in the demand for devices to perform in fragile and confined biological environments, it is crucial to develop new miniaturized, biocompatible 3D systems. Fabrication of materials at different scales with different properties makes 3D printing an ideal system for creating frameworks for small-scale robotics. 3D printing has been applied for the design of externally powered, artificial microswimmers and studying their locomotive capabilities in different fluids. Printed materials have also been incorporated with motile cells for bio-hybrid robots capable of functioning by cell contraction and swimming. These 3D devices offer new methods of robotic motility for biomedical applications requiring miniature structures. Traditional 3D printing methods, where a structure is fabricated in an additive process from a digital design, and non-traditional 3D printing methods, such as lithography and molding, will be discussed.

  2. BioSig3D: High Content Screening of Three-Dimensional Cell Culture Models

    PubMed Central

    Bilgin, Cemal Cagatay; Fontenay, Gerald; Cheng, Qingsu; Chang, Hang; Han, Ju; Parvin, Bahram

    2016-01-01

    BioSig3D is a computational platform for high-content screening of three-dimensional (3D) cell culture models that are imaged in full 3D volume. It provides an end-to-end solution for designing high content screening assays, based on colony organization that is derived from segmentation of nuclei in each colony. BioSig3D also enables visualization of raw and processed 3D volumetric data for quality control, and integrates advanced bioinformatics analysis. The system consists of multiple computational and annotation modules that are coupled together with a strong use of controlled vocabularies to reduce ambiguities between different users. It is a web-based system that allows users to: design an experiment by defining experimental variables, upload a large set of volumetric images into the system, analyze and visualize the dataset, and either display computed indices as a heatmap, or phenotypic subtypes for heterogeneity analysis, or download computed indices for statistical analysis or integrative biology. BioSig3D has been used to profile baseline colony formations with two experiments: (i) morphogenesis of a panel of human mammary epithelial cell lines (HMEC), and (ii) heterogeneity in colony formation using an immortalized non-transformed cell line. These experiments reveal intrinsic growth properties of well-characterized cell lines that are routinely used for biological studies. BioSig3D is being released with seed datasets and video-based documentation. PMID:26978075

  3. Users manual for the NASA Lewis three-dimensional ice accretion code (LEWICE 3D)

    NASA Technical Reports Server (NTRS)

    Bidwell, Colin S.; Potapczuk, Mark G.

    1993-01-01

    A description of the methodology, the algorithms, and the input and output data along with an example case for the NASA Lewis 3D ice accretion code (LEWICE3D) has been produced. The manual has been designed to help the user understand the capabilities, the methodologies, and the use of the code. The LEWICE3D code is a conglomeration of several codes for the purpose of calculating ice shapes on three-dimensional external surfaces. A three-dimensional external flow panel code is incorporated which has the capability of calculating flow about arbitrary 3D lifting and nonlifting bodies with external flow. A fourth order Runge-Kutta integration scheme is used to calculate arbitrary streamlines. An Adams type predictor-corrector trajectory integration scheme has been included to calculate arbitrary trajectories. Schemes for calculating tangent trajectories, collection efficiencies, and concentration factors for arbitrary regions of interest for single droplets or droplet distributions have been incorporated. A LEWICE 2D based heat transfer algorithm can be used to calculate ice accretions along surface streamlines. A geometry modification scheme is incorporated which calculates the new geometry based on the ice accretions generated at each section of interest. The three-dimensional ice accretion calculation is based on the LEWICE 2D calculation. Both codes calculate the flow, pressure distribution, and collection efficiency distribution along surface streamlines. For both codes the heat transfer calculation is divided into two regions, one above the stagnation point and one below the stagnation point, and solved for each region assuming a flat plate with pressure distribution. Water is assumed to follow the surface streamlines, hence starting at the stagnation zone any water that is not frozen out at a control volume is assumed to run back into the next control volume. After the amount of frozen water at each control volume has been calculated the geometry is modified by

  4. Optimal management of reconfigurable manufacturing system modeling with Petri nets developed three-dimensional - RPD3D

    NASA Astrophysics Data System (ADS)

    Teodor, F.; Marinescu, V.; Epureanu, A.

    2016-11-01

    Modeling of reconfigurable manufacturing systems would have done using existing Petri net types, but the complexity and dynamics of the new manufacturing system, mainly data reconfiguration feature, required looking for a more compact representation with many variables that to model as accurately not only the normal operation of the production system but can capture and model and reconfiguration process. Thus, it was necessary to create a new class of Petri nets, called RPD3D (Developed Petri nets with three dimensional) showing the name of both lineage (new class derived from Petri nets developed, created in 2000 by Prof. Dr. Ing Vasile Marinescu in his doctoral thesis) [1], but the most important of the new features defining (transformation from one 2D model into a 3D model).The idea was to introduce the classical model of a Petri third dimension to be able to overlay multiple levels (layers) formed in 2D or 3D Petri nets that interact with each other (receiving or giving commands to enable or disable the various modules together simulating the operation of reconfigurable manufacturing systems). The aim is to present a new type of Petri nets called RPD3D - Developed Petri three-dimensional model used for optimal control and simulation of reconfigurable manufacturing systems manufacture of products such systems.

  5. Multi-slicing strategy for the three-dimensional discontinuity layout optimization (3D DLO).

    PubMed

    Zhang, Yiming

    2017-03-01

    Discontinuity layout optimization (DLO) is a recently presented topology optimization method for determining the critical layout of discontinuities and the associated upper bound limit load for plane two-dimensional and three-dimensional (3D) problems. The modelling process (pre-processing) for DLO includes defining the discontinuities inside a specified domain and building the target function and the global constraint matrix for the optimization solver, which has great influence on the the efficiency of the computation processes and the reliability of the final results. This paper focuses on efficient and reliable pre-processing of the discontinuities within the 3D DLO and presents a multi-slicing strategy, which naturally avoids the overlapping and crossing of different discontinuities. Furthermore, the formulation of the 3D discontinuity considering a shape of an arbitrary convex polygon is introduced, permitting the efficient assembly of the global constraint matrix. The proposed method eliminates unnecessary discontinuities in 3D DLO, making it possible to apply 3D DLO for solving large-scale engineering problems such as those involving landslides. Numerical examples including a footing test, a 3D landslide and a punch indentation are considered, illustrating the effectiveness of the presented method. © 2016 The Authors. International Journal for Numerical and Analytical Methods in Geomechanics published by John Wiley & Sons Ltd.

  6. Accurate three-dimensional pose recognition from monocular images using template matched filtering

    NASA Astrophysics Data System (ADS)

    Picos, Kenia; Diaz-Ramirez, Victor H.; Kober, Vitaly; Montemayor, Antonio S.; Pantrigo, Juan J.

    2016-06-01

    An accurate algorithm for three-dimensional (3-D) pose recognition of a rigid object is presented. The algorithm is based on adaptive template matched filtering and local search optimization. When a scene image is captured, a bank of correlation filters is constructed to find the best correspondence between the current view of the target in the scene and a target image synthesized by means of computer graphics. The synthetic image is created using a known 3-D model of the target and an iterative procedure based on local search. Computer simulation results obtained with the proposed algorithm in synthetic and real-life scenes are presented and discussed in terms of accuracy of pose recognition in the presence of noise, cluttered background, and occlusion. Experimental results show that our proposal presents high accuracy for 3-D pose estimation using monocular images.

  7. Three-dimensional (3D) monolithically integrated photodetector and WDM receiver based on bulk silicon wafer.

    PubMed

    Song, Junfeng; Luo, Xianshu; Tu, Xiaoguang; Jia, Lianxi; Fang, Qing; Liow, Tsung-Yang; Yu, Mingbin; Lo, Guo-Qiang

    2014-08-11

    We propose a novel three-dimensional (3D) monolithic optoelectronic integration platform. Such platform integrates both electrical and photonic devices in a bulk silicon wafer, which eliminates the high-cost silicon-on-insulator (SOI) wafer and is more suitable for process requirements of electronic and photonic integrated circuits (ICs). For proof-of-concept, we demonstrate a three-dimensional photodetector and WDM receiver system. The Ge is grown on a 8-inch bulk silicon wafer while the optical waveguide is defined in a SiN layer which is deposited on top of it, with ~4 µm oxide sandwiched in between. The light is directed to the Ge photodetector from the SiN waveguide vertically by using grating coupler with a Aluminum mirror on top of it. The measured photodetector responsivity is ~0.2 A/W and the 3-dB bandwidth is ~2 GHz. Using such vertical-coupled photodetector, we demonstrated an 8-channel receiver by integrating a 1 × 8 arrayed waveguide grating (AWG). High-quality optical signal detection with up to 10 Gbit/s data rate is demonstrated, suggesting a 80 Gbit/s throughput. Such receiver can be applied to on-chip optical interconnect, DRAM interface, and telecommunication systems.

  8. Kilo-scale droplet generation in three-dimensional monolithic elastomer device (3D MED).

    PubMed

    Jeong, Heon-Ho; Yelleswarapu, Venkata R; Yadavali, Sagar; Issadore, David; Lee, Daeyeon

    2015-12-07

    Droplet-based microfluidics has led to transformational new approaches in diverse areas including materials synthesis and high-throughput biological assays. However, the translation of droplet microfluidics technology into commercial applications requires scale-up of droplet generation from the laboratory (<10 mL h(-1)) to the industrial (>1 L h(-1)) scale. To address this challenge, we develop a three-dimensional monolithic elastomer device (3D MED) for mass production of monodisperse emulsion droplets. Using double-sided imprinting, 3D microchannels are formed in a single elastomer piece that has 1000 parallel flow focusing generators (k-FFGs). Compared to previous work that parallelizes droplet generation, the 3D MED eliminates the needs for alignment and bonding of multiple pieces and thus makes it possible to achieve the high flow rates and pressure necessary for the kilo-scale generation of droplets. Using this approach, we demonstrate mass production of water-in-oil (W/O) emulsion droplets at production rates as high as 1.5 L h(-1) (>30 billion 45 μm diameter droplets per hour), with a coefficient of variation of droplet diameter of only 6.6%. Because of the simplicity, robustness, and manufacturability of our 3D MED architecture, it is well suited to bridge the gap between the continuously growing library of promising microfluidic technologies to generate microparticles that have been demonstrated in laboratory settings and their successful application in industry.

  9. High Content Imaging (HCI) on Miniaturized Three-Dimensional (3D) Cell Cultures

    PubMed Central

    Joshi, Pranav; Lee, Moo-Yeal

    2015-01-01

    High content imaging (HCI) is a multiplexed cell staining assay developed for better understanding of complex biological functions and mechanisms of drug action, and it has become an important tool for toxicity and efficacy screening of drug candidates. Conventional HCI assays have been carried out on two-dimensional (2D) cell monolayer cultures, which in turn limit predictability of drug toxicity/efficacy in vivo; thus, there has been an urgent need to perform HCI assays on three-dimensional (3D) cell cultures. Although 3D cell cultures better mimic in vivo microenvironments of human tissues and provide an in-depth understanding of the morphological and functional features of tissues, they are also limited by having relatively low throughput and thus are not amenable to high-throughput screening (HTS). One attempt of making 3D cell culture amenable for HTS is to utilize miniaturized cell culture platforms. This review aims to highlight miniaturized 3D cell culture platforms compatible with current HCI technology. PMID:26694477

  10. Three-dimensional (3-D) model utilization for fracture reconstruction in oral and maxillofacial surgery: A case report

    NASA Astrophysics Data System (ADS)

    Damayanti, Ista; Lilies, Latief, Benny S.

    2017-02-01

    Three-dimensional (3-D) printing has been identified as an innovative manufacturing technology of functional parts. The 3-D model was produced based on CT-Scan using Osyrix software, where automatic segmentation was performed and convert into STL format. This STL format was then ready to be produced physically, layer-by-layer to create 3-D model.

  11. Three-dimensional recording of the human face with a 3D laser scanner.

    PubMed

    Kovacs, L; Zimmermann, A; Brockmann, G; Gühring, M; Baurecht, H; Papadopulos, N A; Schwenzer-Zimmerer, K; Sader, R; Biemer, E; Zeilhofer, H F

    2006-01-01

    Three-dimensional recording of the surface of the human body or of certain anatomical areas has gained an ever increasing importance in recent years. When recording living surfaces, such as the human face, not only has a varying degree of surface complexity to be accounted for, but also a variety of other factors, such as motion artefacts. It is of importance to establish standards for the recording procedure, which will optimise results and allow for better comparison and validation. In the study presented here, the faces of five male test persons were scanned in different experimental settings using non-contact 3D digitisers, type Minolta Vivid 910). Among others, the influence of the number of scanners used, the angle of recording, the head position of the test person, the impact of the examiner and of examination time on accuracy and precision of the virtual face models generated from the scanner data with specialised software were investigated. Computed data derived from the virtual models were compared to corresponding reference measurements carried out manually between defined landmarks on the test persons' faces. We describe experimental conditions that were of benefit in optimising the quality of scanner recording and the reliability of three-dimensional surface imaging. However, almost 50% of distances between landmarks derived from the virtual models deviated more than 2mm from the reference of manual measurements on the volunteers' faces.

  12. EISCAT 3D: A European three-dimensional imaging radar for atmospheric and geospace research

    NASA Astrophysics Data System (ADS)

    McCrea, Ian; Turunen, Esa

    2010-05-01

    (This talk is given on behalf of the EISCAT Scientific Association and the EISCAT_3D Design Team) EISCAT_3D is a new kind of three-dimensional imaging radar for high-latitude atmosphere and geospace studies, located in northern Scandinavia. The facility will consist of multiple large phased-array antenna transmitters/receivers in three countries, comprising some 100 000 individual antenna elements. The new radars will measure from the upper stratosphere to the magnetosphere and beyond, contributing to the basic, environmental and applied science that underpins the use of space by contemporary society. EISCAT_3D's capabilities go beyond anything currently available to the international research community, and will form a significant enhancement to the European Research area. Located in the auroral zone, at the edge of the northern polar vortex, EISCAT_3D will provide long-term continuous data for scientists studying global change, measuring the effects of man-made and natural variability on the middle and upper atmosphere. Its observations will underpin space weather prediction and monitoring, essential for operation and improved service of European space assets. In addition, EISCAT_3D will facilitate studies of solar system influences, such as solar wind, meteors, dust, energetic particles and cosmic rays. This will be done in collaboration with other research infrastructures, including the upper atmosphere programme of the SIOS proposal, focusing on observations made from Svalbard. The importance of EISCAT_3D has been recognised by its place on the ESFRI roadmap of future European Research facilities. The project has already gone through a four-year design study, funded by the European Union under the 6th Framework, and has recently applied for Preparatory Phase funding under the EU 7th Framework. The Preparatory Phase activities will facilitate the resolution of the remaining legal, financial and technical questions which must be addressed before EISCAT_3D can be

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

    PubMed Central

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

    2002-01-01

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

  14. Pattern Transformation of Heat-Shrinkable Polymer by Three-Dimensional (3D) Printing Technique

    PubMed Central

    Zhang, Quan; Yan, Dong; Zhang, Kai; Hu, Gengkai

    2015-01-01

    A significant challenge in conventional heat-shrinkable polymers is to produce controllable microstructures. Here we report that the polymer material fabricated by three-dimensional (3D) printing technique has a heat-shrinkable property, whose initial microstructure can undergo a spontaneous pattern transformation under heating. The underlying mechanism is revealed by evaluating internal strain of the printed polymer from its fabricating process. It is shown that a uniform internal strain is stored in the polymer during the printing process and can be released when heated above its glass transition temperature. Furthermore, the internal strain can be used to trigger the pattern transformation of the heat-shrinkable polymer in a controllable way. Our work provides insightful ideas to understand a novel mechanism on the heat-shrinkable effect of printed material, but also to present a simple approach to fabricate heat-shrinkable polymer with a controllable thermo-structural response. PMID:25757881

  15. Three-dimensional simulations of high-current beams in induction accelerators with WARP3d

    SciTech Connect

    Grote, D.P.; Friedman, A.; Haber, I.

    1995-09-01

    For many issues relevant to acceleration and propagation of heavy-ion beams for inertial confinement fusion, understanding the behavior of the beam requires the self-consistent inclusion of the self-fields of the beams in multiple dimensions. For these reasons, the three-dimensional simulation code WARP3d A.Friedman was developed. The code combines the particle-in-cell plasma simulation technique with a realistic description of the elements which make up an accelerator. In this paper, the general structure of the code is reviewed and details of two ongoing applications are presented along with a discussion of simulation techniques used. The most important results of this work are presented.

  16. A Soft Sensor-Based Three-Dimensional (3-D) Finger Motion Measurement System

    PubMed Central

    Park, Wookeun; Ro, Kyongkwan; Kim, Suin; Bae, Joonbum

    2017-01-01

    In this study, a soft sensor-based three-dimensional (3-D) finger motion measurement system is proposed. The sensors, made of the soft material Ecoflex, comprise embedded microchannels filled with a conductive liquid metal (EGaln). The superior elasticity, light weight, and sensitivity of soft sensors allows them to be embedded in environments in which conventional sensors cannot. Complicated finger joints, such as the carpometacarpal (CMC) joint of the thumb are modeled to specify the location of the sensors. Algorithms to decouple the signals from soft sensors are proposed to extract the pure flexion, extension, abduction, and adduction joint angles. The performance of the proposed system and algorithms are verified by comparison with a camera-based motion capture system. PMID:28241414

  17. Methods used in WARP3d, a three-dimensional PIC/accelerator code

    SciTech Connect

    Grote, D.P.; Friedman, A.; Haber, I.

    1997-02-28

    WARP-3d(1,2), a three-dimensional PIC/accelerator code, has been developed over several years and has played a major role in the design and analysis of space-charge dominated beam experiments being carried out by the heavy-ion fusion programs at LLNL and LBNL. Major features of the code will be reviewed, including: residence corrections which allow large timesteps to be taken, electrostatic field solution with subgrid scale resolution of internal conductor boundaries, and a beat beam algorithm. Emphasis will be placed on new features and capabilities of the code, which include: a port to parallel processing environments, space-charge limited injection, and the linking of runs covering different sections of an accelerator. Representative applications in which the new features and capabilities are used will be presented along with the important results.

  18. Emission of particulate matter from a desktop three-dimensional (3D) printer.

    PubMed

    Yi, Jinghai; LeBouf, Ryan F; Duling, Matthew G; Nurkiewicz, Timothy; Chen, Bean T; Schwegler-Berry, Diane; Virji, M Abbas; Stefaniak, Aleksandr B

    2016-01-01

    Desktop three-dimensional (3D) printers are becoming commonplace in business offices, public libraries, university labs and classrooms, and even private homes; however, these settings are generally not designed for exposure control. Prior experience with a variety of office equipment devices such as laser printers that emit ultrafine particles (UFP) suggests the need to characterize 3D printer emissions to enable reliable risk assessment. The aim of this study was to examine factors that influence particulate emissions from 3D printers and characterize their physical properties to inform risk assessment. Emissions were evaluated in a 0.5-m(3) chamber and in a small room (32.7 m(3)) using real-time instrumentation to measure particle number, size distribution, mass, and surface area. Factors evaluated included filament composition and color, as well as the manufacturer-provided printer emissions control technologies while printing an object. Filament type significantly influenced emissions, with acrylonitrile butadiene styrene (ABS) emitting larger particles than polylactic acid (PLA), which may have been the result of agglomeration. Geometric mean particle sizes and total particle (TP) number and mass emissions differed significantly among colors of a given filament type. Use of a cover on the printer reduced TP emissions by a factor of 2. Lung deposition calculations indicated a threefold higher PLA particle deposition in alveoli compared to ABS. Desktop 3D printers emit high levels of UFP, which are released into indoor environments where adequate ventilation may not be present to control emissions. Emissions in nonindustrial settings need to be reduced through the use of a hierarchy of controls, beginning with device design, followed by engineering controls (ventilation) and administrative controls such as choice of filament composition and color.

  19. Emission of particulate matter from a desktop three-dimensional (3D) printer

    PubMed Central

    Yi, Jinghai; LeBouf, Ryan F.; Duling, Matthew G.; Nurkiewicz, Timothy; Chen, Bean T.; Schwegler-Berry, Diane; Virji, M. Abbas; Stefaniak, Aleksandr B.

    2016-01-01

    ABSTRACT Desktop three-dimensional (3D) printers are becoming commonplace in business offices, public libraries, university labs and classrooms, and even private homes; however, these settings are generally not designed for exposure control. Prior experience with a variety of office equipment devices such as laser printers that emit ultrafine particles (UFP) suggests the need to characterize 3D printer emissions to enable reliable risk assessment. The aim of this study was to examine factors that influence particulate emissions from 3D printers and characterize their physical properties to inform risk assessment. Emissions were evaluated in a 0.5-m3 chamber and in a small room (32.7 m3) using real-time instrumentation to measure particle number, size distribution, mass, and surface area. Factors evaluated included filament composition and color, as well as the manufacturer-provided printer emissions control technologies while printing an object. Filament type significantly influenced emissions, with acrylonitrile butadiene styrene (ABS) emitting larger particles than polylactic acid (PLA), which may have been the result of agglomeration. Geometric mean particle sizes and total particle (TP) number and mass emissions differed significantly among colors of a given filament type. Use of a cover on the printer reduced TP emissions by a factor of 2. Lung deposition calculations indicated a threefold higher PLA particle deposition in alveoli compared to ABS. Desktop 3D printers emit high levels of UFP, which are released into indoor environments where adequate ventilation may not be present to control emissions. Emissions in nonindustrial settings need to be reduced through the use of a hierarchy of controls, beginning with device design, followed by engineering controls (ventilation) and administrative controls such as choice of filament composition and color. PMID:27196745

  20. An Accurate von Neumann's Law for Three-Dimensional Foams

    SciTech Connect

    Hilgenfeldt, Sascha; Kraynik, Andrew M.; Koehler, Stephan A.; Stone, Howard A.

    2001-03-19

    The diffusive coarsening of 2D soap froths is governed by von Neumann's law. A statistical version of this law for dry 3D foams has long been conjectured. A new derivation, based on a theorem by Minkowski, yields an explicit analytical von Neumann's law in 3D which is in very good agreement with detailed simulations and experiments. The average growth rate of a bubble with F faces is shown to be proportional to F{sup 1/2} for large F , in contrast to the conjectured linear dependence. Accounting for foam disorder in the model further improves the agreement with data.

  1. Three-dimensional (3D) hydrodynamic focusing for continuous sampling and analysis of adherent cells.

    PubMed

    Xu, Chunxiu; Wang, Min; Yin, Xuefeng

    2011-10-07

    A simple three-dimensional (3D) hydrodynamic focusing microfluidic device integrated with continuous sampling, rapid dynamic lysis, capillary electrophoretic (CE) separation and detection of intracellular content is presented. One of the major difficulties in microfluidic cell analysis for adherent cells is that the cells are prone to attaching to the channel surface. To solve this problem, a cross microfluidic chip with three sheath-flow channels located on both sides of and below the sampling channel was developed. With the three sheath flows around the sample solution-containing cells, the formed soft fluid wall prevents the cells from adhering to the channel surface. Labeled cells were 3D hydrodynamically focused by the sheath-flow streams and smoothly introduced into the cross-section one by one. The introduction of sheath-flow streams not only ensured single-cell sampling but avoided blockage of the sampling channel by adherent cells as well. The maximum rate for introduction of individual cells into the separation channel was about 151 cells min(-1). With electric field applied on the separation channel, the aligned cells were driven into the separation channel and rapidly lysed within 400 ms at the entry of the channel by sodium dodecylsulfate (SDS) added in the sheath-flow solution. The microfluidic system was evaluated by analysis of reduced glutathione (GSH) and reactive oxygen species (ROS) in single HepG2 cells. The average analysis throughput of ROS and GSH in single cells was 16-18 cells min(-1).

  2. Towards a gestural 3D interaction for tangible and three-dimensional GIS visualizations

    NASA Astrophysics Data System (ADS)

    Partsinevelos, Panagiotis; Agadakos, Ioannis; Pattakos, Nikolas; Maragakis, Michail

    2014-05-01

    The last decade has been characterized by a significant increase of spatially dependent applications that require storage, visualization, analysis and exploration of geographic information. GIS analysis of spatiotemporal geographic data is operated by highly trained personnel under an abundance of software and tools, lacking interoperability and friendly user interaction. Towards this end, new forms of querying and interaction are emerging, including gestural interfaces. Three-dimensional GIS representations refer to either tangible surfaces or projected representations. Making a 3D tangible geographic representation touch-sensitive may be a convenient solution, but such an approach raises the cost significantly and complicates the hardware and processing required to combine touch-sensitive material (for pinpointing points) with deformable material (for displaying elevations). In this study, a novel interaction scheme upon a three dimensional visualization of GIS data is proposed. While gesture user interfaces are not yet fully acceptable due to inconsistencies and complexity, a non-tangible GIS system where 3D visualizations are projected, calls for interactions that are based on three-dimensional, non-contact and gestural procedures. Towards these objectives, we use the Microsoft Kinect II system which includes a time of flight camera, allowing for a robust and real time depth map generation, along with the capturing and translation of a variety of predefined gestures from different simultaneous users. By incorporating these features into our system architecture, we attempt to create a natural way for users to operate on GIS data. Apart from the conventional pan and zoom features, the key functions addressed for the 3-D user interface is the ability to pinpoint particular points, lines and areas of interest, such as destinations, waypoints, landmarks, closed areas, etc. The first results shown, concern a projected GIS representation where the user selects points

  3. Thoracic Pedicle Screw Placement Guide Plate Produced by Three-Dimensional (3-D) Laser Printing

    PubMed Central

    Chen, Hongliang; Guo, Kaijing; Yang, Huilin; Wu, Dongying; Yuan, Feng

    2016-01-01

    Background The aim of this study was to evaluate the accuracy and feasibility of an individualized thoracic pedicle screw placement guide plate produced by 3-D laser printing. Material/Methods Thoracic pedicle samples of 3 adult cadavers were randomly assigned for 3-D CT scans. The 3-D thoracic models were established by using medical Mimics software, and a screw path was designed with scanned data. Then the individualized thoracic pedicle screw placement guide plate models, matched to the backside of thoracic vertebral plates, were produced with a 3-D laser printer. Screws were placed with assistance of a guide plate. Then, the placement was assessed. Results With the data provided by CT scans, 27 individualized guide plates were produced by 3-D printing. There was no significant difference in sex and relevant parameters of left and right sides among individuals (P>0.05). Screws were placed with assistance of guide plates, and all screws were in the correct positions without penetration of pedicles, under direct observation and anatomic evaluation post-operatively. Conclusions A thoracic pedicle screw placement guide plate can be produced by 3-D printing. With a high accuracy in placement and convenient operation, it provides a new method for accurate placement of thoracic pedicle screws. PMID:27194139

  4. Comparing Microfluidic Performance of Three-Dimensional (3D) Printing Platforms.

    PubMed

    Macdonald, Niall P; Cabot, Joan M; Smejkal, Petr; Guijt, Rosanne M; Paull, Brett; Breadmore, Michael C

    2017-03-24

    Three-dimensional (3D) printing has emerged as a potential revolutionary technology for the fabrication of microfluidic devices. A direct experimental comparison of the three 3D printing technologies dominating microfluidics was conducted using a Y-junction microfluidic device, the design of which was optimized for each printer: fused deposition molding (FDM), Polyjet, and digital light processing stereolithography (DLP-SLA). Printer performance was evaluated in terms of feature size, accuracy, and suitability for mass manufacturing; laminar flow was studied to assess their suitability for microfluidics. FDM was suitable for microfabrication with minimum features of 321 ± 5 μm, and rough surfaces of 10.97 μm. Microfluidic devices >500 μm, rapid mixing (71% ± 12% after 5 mm, 100 μL/min) was observed, indicating a strength in fabricating micromixers. Polyjet fabricated channels with a minimum size of 205 ± 13 μm, and a surface roughness of 0.99 μm. Compared with FDM, mixing decreased (27% ± 10%), but Polyjet printing is more suited for microfluidic applications where flow splitting is not required, such as cell culture or droplet generators. DLP-SLA fabricated a minimum channel size of 154 ± 10 μm, and 94 ± 7 μm for positive structures such as soft lithography templates, with a roughness of 0.35 μm. These results, in addition to low mixing (8% ± 1%), showed suitability for microfabrication, and microfluidic applications requiring precise control of flow. Through further discussion of the capabilities (and limitations) of these printers, we intend to provide guidance toward the selection of the 3D printing technology most suitable for specific microfluidic applications.

  5. 3D-ANTLERS: Virtual Reconstruction and Three-Dimensional Measurement

    NASA Astrophysics Data System (ADS)

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

    2013-02-01

    The main objective of this paper is to establish a procedural method for measuring and cataloguing antlers through the use of laser scanner and of a 3D reconstruction of complex modeling. The deer's antlers have been used as a test and subjected to capture and measurement. For this purpose multiple data sources techniques have been studied and compared, (also considering low-cost sensors) estimating the accuracy and its errors in order to demonstrate the validity of the process. A further development is the comparison of results with applications of digital photogrammetry, considering also cloud computing software. The study has began with an introduction to sensors, addressing the underlying characteristics of the technology available, the scope and the limits of these applications. We have focused particularly on the "structured light", as the acquisition will be completed through three-dimensional scanners: DAVID and the ARTEC MH. The first is a low-cost sensor, a basic webcam and a linear laser pointer, red coloured, that leads to acquisition of three-dimensional strips. The other one is a hand scanner; even in this case we will explain how to represent a 3D model, with a pipeline that provides data export from the "proprietary" to a "reverse engineering" software. Typically, these are the common steps to the two approaches that have been performed in WRAP format: point sampling, manual and global registration, repair normals, surface editing and texture projection. In fact, after a first and common data processing was done with the use of a software supplied with the equipment, the proto-models thus obtained were treated in Geomagic Studio, which was also chosen to allow the homogenization and standardization of data in order to make a more objective comparison. It is commonplace to observe that the editing of the digital mock-up obtained with the DAVID - which had not yet been upgraded to the 3.5 release at the time of this study - is substantially different

  6. Numerical simulation of jet aerodynamics using the three-dimensional Navier-Stokes code PAB3D

    NASA Technical Reports Server (NTRS)

    Pao, S. Paul; Abdol-Hamid, Khaled S.

    1996-01-01

    This report presents a unified method for subsonic and supersonic jet analysis using the three-dimensional Navier-Stokes code PAB3D. The Navier-Stokes code was used to obtain solutions for axisymmetric jets with on-design operating conditions at Mach numbers ranging from 0.6 to 3.0, supersonic jets containing weak shocks and Mach disks, and supersonic jets with nonaxisymmetric nozzle exit geometries. This report discusses computational methods, code implementation, computed results, and comparisons with available experimental data. Very good agreement is shown between the numerical solutions and available experimental data over a wide range of operating conditions. The Navier-Stokes method using the standard Jones-Launder two-equation kappa-epsilon turbulence model can accurately predict jet flow, and such predictions are made without any modification to the published constants for the turbulence model.

  7. Design and testing of indigenous cost effective three dimensional radiation field analyser (3D RFA).

    PubMed

    Ganesh, K M; Pichandi, A; Nehru, R M; Ravikumar, M

    2014-06-01

    The aim of the study is to design and validate an indigenous three dimensional Radiation Field Analyser (3D RFA). The feed system made for X, Y and Z axis movements is of lead screw with deep ball bearing mechanism made up of stain less steel driven by stepper motors with accuracy less than 0.5 mm. The telescopic column lifting unit was designed using linear actuation technology for lifting the water phantom. The acrylic phantom with dimensions of 800 x 750 x 570 mm was made with thickness of 15 mm. The software was developed in visual basic programming language, classified into two types, viz. beam analyzer software and beam acquisition software. The premeasurement checks were performed as per TG 106 recommendations. The physical parameters of photon PDDs such as Dmax, D10, D20 and Quality Index (QI), and the electron PDDs such as R50, Rp, E0, Epo and X-ray contamination values can be obtained instantaneously by using the developed RFA system. Also the results for profile data such as field size, central axis deviation, penumbra, flatness and symmetry calculated according to various protocols can be obtained for both photon and electron beams. The result of PDDs for photon beams were compared with BJR25 supplement values and the profile data were compared with TG 40 recommendation. The results were in agreement with standard protocols.

  8. Development of AN Innovative Three-Dimensional Complete Body Screening Device - 3D-CBS

    NASA Astrophysics Data System (ADS)

    Crosetto, D. B.

    2004-07-01

    This article describes an innovative technological approach that increases the efficiency with which a large number of particles (photons) can be detected and analyzed. The three-dimensional complete body screening (3D-CBS) combines the functional imaging capability of the Positron Emission Tomography (PET) with those of the anatomical imaging capability of Computed Tomography (CT). The novel techniques provide better images in a shorter time with less radiation to the patient. A primary means of accomplishing this is the use of a larger solid angle, but this requires a new electronic technique capable of handling the increased data rate. This technique, combined with an improved and simplified detector assembly, enables executing complex real-time algorithms and allows more efficiently use of economical crystals. These are the principal features of this invention. A good synergy of advanced techniques in particle detection, together with technological progress in industry (latest FPGA technology) and simple, but cost-effective ideas provide a revolutionary invention. This technology enables over 400 times PET efficiency improvement at once compared to two to three times improvements achieved every five years during the past decades. Details of the electronics are provided, including an IBM PC board with a parallel-processing architecture implemented in FPGA, enabling the execution of a programmable complex real-time algorithm for best detection of photons.

  9. Extension of a three-dimensional viscous wing flow analysis user's manual: VISTA 3-D code

    NASA Technical Reports Server (NTRS)

    Weinberg, Bernard C.; Chen, Shyi-Yaung; Thoren, Stephen J.; Shamroth, Stephen J.

    1990-01-01

    Three-dimensional unsteady viscous effects can significantly influence the performance of fixed and rotary wing aircraft. These effects are important in both flows about helicopter rotors in forward flight and flows about three-dimensional (swept and tapered) supercritical wings. A computational procedure for calculating such flow field was developed. The procedure is based upon an alternating direction technique employing the Linearized Block Implicit method for solving three-dimensional viscous flow problems. In order to demonstrate the viability of this method, two- and three-dimensional problems are computed. These include the flow over a two-dimensional NACA 0012 airfoil under steady and oscillating conditions, and the steady, skewed, three-dimensional flow on a flat plate. Although actual three-dimensional flows over wings were not obtained, the ground work was laid for considering such flows. In this report a description of the computer code is given.

  10. THREE DIMENSIONAL INTEGRATED CHARACTERIZATION AND ARCHIVING SYSTEM (3D-ICAS)

    SciTech Connect

    George Jarvis

    2001-06-18

    The overall objective of this project is to develop an integrated system that remotely characterizes, maps, and archives measurement data of hazardous decontamination and decommissioning (D&D) areas. The system will generate a detailed 3-dimensional topography of the area as well as real-time quantitative measurements of volatile organics and radionuclides. The system will analyze substrate materials consisting of concrete, asbestos, and transite. The system will permanently archive the data measurements for regulatory and data integrity documentation. Exposure limits, rest breaks, and donning and removal of protective garments generate waste in the form of contaminated protective garments and equipment. Survey times are increased and handling and transporting potentially hazardous materials incur additional costs. Off-site laboratory analysis is expensive and time-consuming, often necessitating delay of further activities until results are received. The Three Dimensional Integrated Characterization and Archiving System (3D-ICAS) has been developed to alleviate some of these problems. 3D-ICAS provides a flexible system for physical, chemical and nuclear measurements reduces costs and improves data quality. Operationally, 3D-ICAS performs real-time determinations of hazardous and toxic contamination. A prototype demonstration unit is available for use in early 2000. The tasks in this Phase included: (1) Mobility Platforms: Integrate hardware onto mobility platforms, upgrade surface sensors, develop unit operations and protocol. (2) System Developments: Evaluate metals detection capability using x-ray fluorescence technology. (3) IWOS Upgrades: Upgrade the IWOS software and hardware for compatibility with mobility platform. The system was modified, tested and debugged during 1999 and 2000. The 3D-ICAS was shipped on 11 May 2001 to FIU-HCET for demonstration and validation of the design modifications. These modifications included simplifying the design from a two

  11. Acoustic Scattering by Three-Dimensional Stators and Rotors Using the SOURCE3D Code. Volume 2; Scattering Plots

    NASA Technical Reports Server (NTRS)

    Meyer, Harold D.

    1999-01-01

    This second volume of Acoustic Scattering by Three-Dimensional Stators and Rotors Using the SOURCE3D Code provides the scattering plots referenced by Volume 1. There are 648 plots. Half are for the 8750 rpm "high speed" operating condition and the other half are for the 7031 rpm "mid speed" operating condition.

  12. Emerging role of three-dimensional speckle tracking strain for accurate quantification of left ventricular dyssynchrony.

    PubMed

    Tanaka, Hidekazu; Tatsumi, Kazuhiro; Matsumoto, Kensuke; Kawai, Hiroya; Hirata, Ken-ichi

    2013-10-01

    A case was 53-year-old female with dilated-phase hypertrophic cardiomyopathy. She was classified as New York Heart Association functional class III heart failure despite receiving optimal medical therapy. The electrocardiogram taken showed intraventricular conduction delay with a QRS width of 194 msec. The left ventricular (LV) end-diastolic and systolic volumes, and ejection fraction (EF) were 101 mL, 68 mL, and 32%, respectively. The patient showed no significant mechanical LV dyssynchrony as evidenced by two-dimensional (2D) speckle tracking radial strain, which is defined as the time difference between anterior-septum and posterior wall, of 105 msec (<130 msec). Three-dimensional (3D) speckle tracking radial strain was performed for more detailed LV mechanical dyssynchrony analysis. An especially important finding for 3D speckle tracking radial strain analysis was that the average time-to-peak strain of 5 septum segments at 3 different LV levels (basal-anterior-septum, basal-septum, mid-anterior-septum, mid-septum, apical-septum) was significantly shorter than that of 5 posterolateral segments at 3 different LV levels (basal-posterior, basal-lateral, mid-posterior, mid-lateral, apical-lateral). This time difference between septum and posterolateral wall was 216 msec (204 msec vs. 420 msec), which was considered to indicate significant LV mechanical dyssynchrony (≥130 msec). 12 months after cardiac resynchronization therapy (CRT), EF had improved to 47%, while end-systolic and diastolic volumes had decreased to 88 mL and 47 mL, respectively, so that the patient was classified as a responder. In conclusions, a newly developed 3D speckle tracking strain can provide a comprehensive evaluation of "true" LV mechanical dyssynchrony from pyramidal 3D data sets acquired in the same beat, thus yielding more accurate information than previously possible with the 2D speckle tracking system.

  13. Automated Atom-By-Atom Three-Dimensional (3D) Reconstruction of Field Ion Microscopy Data.

    PubMed

    Dagan, Michal; Gault, Baptiste; Smith, George D W; Bagot, Paul A J; Moody, Michael P

    2017-03-20

    An automated procedure has been developed for the reconstruction of field ion microscopy (FIM) data that maintains its atomistic nature. FIM characterizes individual atoms on the specimen's surface, evolving subject to field evaporation, in a series of two-dimensional (2D) images. Its unique spatial resolution enables direct imaging of crystal defects as small as single vacancies. To fully exploit FIM's potential, automated analysis tools are required. The reconstruction algorithm developed here relies on minimal assumptions and is sensitive to atomic coordinates of all imaged atoms. It tracks the atoms across a sequence of images, allocating each to its respective crystallographic plane. The result is a highly accurate 3D lattice-resolved reconstruction. The procedure is applied to over 2000 tungsten atoms, including ion-implanted planes. The approach is further adapted to analyze carbides in a steel matrix, demonstrating its applicability to a range of materials. A vast amount of information is collected during the experiment that can underpin advanced analyses such as automated detection of "out of sequence" events, subangstrom surface displacements and defects effects on neighboring atoms. These analyses have the potential to reveal new insights into the field evaporation process and contribute to improving accuracy and scope of 3D FIM and atom probe characterization.

  14. Design and test of a PC-based portable three-dimensional ultrasound software system Ultra3D.

    PubMed

    Xu, X George; Hum Na, Yong; Zhang, Tiantian

    2008-02-01

    Currently, portable ultrasound units lack three-dimensional (3D) image display, limiting their potential usefulness especially under remote and hostile operating environments where information must be intuitive and objective. A freehand 3D image processing and visualization software package, Ultra3D, has been developed and tested, especially to work with a miniaturized linear-array transducer probe that is connected to a laptop PC. This paper presents the software design and method to integrate Ultra3D into Terason's miniaturized SmartProbe for freehand 3D ultrasound imaging. Since images generated by Ultra3D are in a digital imaging and communications in medicine (DICOM) format, data sharing with others is easy.

  15. Chrom3D: three-dimensional genome modeling from Hi-C and nuclear lamin-genome contacts.

    PubMed

    Paulsen, Jonas; Sekelja, Monika; Oldenburg, Anja R; Barateau, Alice; Briand, Nolwenn; Delbarre, Erwan; Shah, Akshay; Sørensen, Anita L; Vigouroux, Corinne; Buendia, Brigitte; Collas, Philippe

    2017-01-30

    Current three-dimensional (3D) genome modeling platforms are limited by their inability to account for radial placement of loci in the nucleus. We present Chrom3D, a user-friendly whole-genome 3D computational modeling framework that simulates positions of topologically-associated domains (TADs) relative to each other and to the nuclear periphery. Chrom3D integrates chromosome conformation capture (Hi-C) and lamin-associated domain (LAD) datasets to generate structure ensembles that recapitulate radial distributions of TADs detected in single cells. Chrom3D reveals unexpected spatial features of LAD regulation in cells from patients with a laminopathy-causing lamin mutation. Chrom3D is freely available on github.

  16. Single-layer planar on-chip flow cytometer using microfluidic drifting based three-dimensional (3D) hydrodynamic focusing.

    PubMed

    Mao, Xiaole; Lin, Sz-Chin Steven; Dong, Cheng; Huang, Tony Jun

    2009-06-07

    In this work, we demonstrate an on-chip microfluidic flow cytometry system based on a three-dimensional (3D) hydrodynamic focusing technique, microfluidic drifting. By inducing Dean flow in a curved microfluidic channel, microfluidic drifting can be used to hydrodynamically focus cells or particles in the vertical direction and enables the 3D hydrodynamic focusing in a single-layer planar microfluidic device. Through theoretical calculation, numerical simulation, and experimental characterization, we found that the microfluidic drifting technique can be effectively applied to three-dimensionally focus microparticles with density and size equivalent to those of human CD4+ T lymphocytes. In addition, we developed a flow cytometry platform by integrating the 3D focusing device with a laser-induced fluorescence (LIF) detection system. The system was shown to provide effective high-throughput flow cytometry measurements at a rate of greater than 1700 cells s(-1).

  17. Three-dimensional two-fluid investigation of 3D-localized magnetic reconnection and its relation to whistler waves

    NASA Astrophysics Data System (ADS)

    Yoon, Young Dae; Bellan, Paul M.

    2016-10-01

    A full three-dimensional computer code was developed in order to simulate a 3D-localized magnetic reconnection. We assume an incompressible two-fluid regime where the ions are stationary, and electron inertia and Hall effects are present. We solve a single dimensionless differential equation for perturbed magnetic fields with arbitrary background fields. The code has successfully reproduced both experimental and analytic solutions to resonance and Gendrin mode whistler waves in a uniform background field. The code was then modified to model 3D-localized magnetic reconnection as a 3D-localized perturbation on a hyperbolic-tangent background field. Three-dimensional properties that are asymmetric in the out-of-plane direction have been observed. These properties pertained to magnetic field lines, electron currents and their convection. Helicity and energy have also been examined, as well as the addition of a guide field.

  18. A defocus-information-free autostereoscopic three-dimensional (3D) digital reconstruction method using direct extraction of disparity information (DEDI)

    NASA Astrophysics Data System (ADS)

    Li, Da; Cheung, Chifai; Zhao, Xing; Ren, Mingjun; Zhang, Juan; Zhou, Liqiu

    2016-10-01

    Autostereoscopy based three-dimensional (3D) digital reconstruction has been widely applied in the field of medical science, entertainment, design, industrial manufacture, precision measurement and many other areas. The 3D digital model of the target can be reconstructed based on the series of two-dimensional (2D) information acquired by the autostereoscopic system, which consists multiple lens and can provide information of the target from multiple angles. This paper presents a generalized and precise autostereoscopic three-dimensional (3D) digital reconstruction method based on Direct Extraction of Disparity Information (DEDI) which can be used to any transform autostereoscopic systems and provides accurate 3D reconstruction results through error elimination process based on statistical analysis. The feasibility of DEDI method has been successfully verified through a series of optical 3D digital reconstruction experiments on different autostereoscopic systems which is highly efficient to perform the direct full 3D digital model construction based on tomography-like operation upon every depth plane with the exclusion of the defocused information. With the absolute focused information processed by DEDI method, the 3D digital model of the target can be directly and precisely formed along the axial direction with the depth information.

  19. The three-dimensional elemental distribution based on the surface topography by confocal 3D-XRF analysis

    NASA Astrophysics Data System (ADS)

    Yi, Longtao; Qin, Min; Wang, Kai; Lin, Xue; Peng, Shiqi; Sun, Tianxi; Liu, Zhiguo

    2016-09-01

    Confocal three-dimensional micro-X-ray fluorescence (3D-XRF) is a good surface analysis technology widely used to analyse elements and elemental distributions. However, it has rarely been applied to analyse surface topography and 3D elemental mapping in surface morphology. In this study, a surface adaptive algorithm using the progressive approximation method was designed to obtain surface topography. A series of 3D elemental mapping analyses in surface morphology were performed in laboratories to analyse painted pottery fragments from the Majiayao Culture (3300-2900 BC). To the best of our knowledge, for the first time, sample surface topography and 3D elemental mapping were simultaneously obtained. Besides, component and depth analyses were also performed using synchrotron radiation confocal 3D-XRF and tabletop confocal 3D-XRF, respectively. The depth profiles showed that the sample has a layered structure. The 3D elemental mapping showed that the red pigment, black pigment, and pottery coat contain a large amount of Fe, Mn, and Ca, respectively. From the 3D elemental mapping analyses at different depths, a 3D rendering was obtained, clearly showing the 3D distributions of the red pigment, black pigment, and pottery coat. Compared with conventional 3D scanning, this method is time-efficient for analysing 3D elemental distributions and hence especially suitable for samples with non-flat surfaces.

  20. 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.

  1. Three-dimensional subsurface imaging synthetic aperture radar (3D SISAR). Final report, September 22, 1993--September 22, 1996

    SciTech Connect

    1998-12-31

    The concept developed under this applied research and development contract is a novel Ground Penetrating Radar system capable of remotely detecting, analyzing, and mapping buried waste containers from a mobile platform. From the testing and analysis performed to date, the 3-D SISAR has achieved the detection, accurate location, and three-dimensional imaging of buried test objects from a stand-off geometry. Tests have demonstrated that underground objects have been located to within 0.1 meter of their actual position. This work validates that the key elements of the approach are performing as anticipated. The stand-off synthetic aperture radar (SAR) methodology has been demonstrated to be a feasible approach as a remote sensing technique. The radar sensor constructed under this project is providing adequate quality data for imaging, and the matched filters have been demonstrated to provide enhanced target detection. Additional work is on-going in the area of underground propagation and scattering phenomena to provide enhanced depth performance, as the current imaging results have been limited to a few feet of depth underground.

  2. Smart three-dimensional lightweight structure triggered from a thin composite sheet via 3D printing technique

    PubMed Central

    Zhang, Quan; Zhang, Kai; Hu, Gengkai

    2016-01-01

    Complex fabrication process and expensive materials have restricted the development of smart three-dimensional (3D) lightweight structures, which are expected to possess self-shaping, self-folding and self-unfolding performances. Here we present a simple approach to fabricate smart lightweight structures by triggering shape transformation from thin printed composite sheets. The release of the internal strain in printed polymer materials enables the printed composite sheet to keep flat under heating and transform into a designed 3D configuration when cooled down to room temperature. The 3D lightweight structure can be switched between flat and 3D configuration under appropriate thermal stimuli. Our work exploits uniform internal strain in printed materials as a controllable tool to fabricate smart 3D lightweight structures, opening an avenue for possible applications in engineering fields. PMID:26926357

  3. Smart three-dimensional lightweight structure triggered from a thin composite sheet via 3D printing technique

    NASA Astrophysics Data System (ADS)

    Zhang, Quan; Zhang, Kai; Hu, Gengkai

    2016-02-01

    Complex fabrication process and expensive materials have restricted the development of smart three-dimensional (3D) lightweight structures, which are expected to possess self-shaping, self-folding and self-unfolding performances. Here we present a simple approach to fabricate smart lightweight structures by triggering shape transformation from thin printed composite sheets. The release of the internal strain in printed polymer materials enables the printed composite sheet to keep flat under heating and transform into a designed 3D configuration when cooled down to room temperature. The 3D lightweight structure can be switched between flat and 3D configuration under appropriate thermal stimuli. Our work exploits uniform internal strain in printed materials as a controllable tool to fabricate smart 3D lightweight structures, opening an avenue for possible applications in engineering fields.

  4. Smart three-dimensional lightweight structure triggered from a thin composite sheet via 3D printing technique.

    PubMed

    Zhang, Quan; Zhang, Kai; Hu, Gengkai

    2016-02-29

    Complex fabrication process and expensive materials have restricted the development of smart three-dimensional (3D) lightweight structures, which are expected to possess self-shaping, self-folding and self-unfolding performances. Here we present a simple approach to fabricate smart lightweight structures by triggering shape transformation from thin printed composite sheets. The release of the internal strain in printed polymer materials enables the printed composite sheet to keep flat under heating and transform into a designed 3D configuration when cooled down to room temperature. The 3D lightweight structure can be switched between flat and 3D configuration under appropriate thermal stimuli. Our work exploits uniform internal strain in printed materials as a controllable tool to fabricate smart 3D lightweight structures, opening an avenue for possible applications in engineering fields.

  5. Extended three-dimensional digital image correlation (X3D-DIC)

    NASA Astrophysics Data System (ADS)

    Réthoré, Julien; Tinnes, Jean-Philippe; Roux, Stéphane; Buffière, Jean-Yves; Hild, François

    2008-08-01

    A correlation algorithm is proposed to measure full three-dimensional displacement fields in a three-dimensional domain. The chosen kinematic basis for this measurement is based on continuous finite-element shape functions. It is furthermore proposed to account for the presence of strong discontinuities, similarly to extended finite element schemes, with a suited enrichment of the kinematics with discontinuities supported by a (crack) surface. An optimization of the surface geometry is proposed based on correlation residuals. The procedure is applied to analyze one loading cycle of a fatigue-cracked nodular graphite cast iron sample by using computed tomography pictures. Subvoxel crack openings are revealed and measured. To cite this article: J. Réthoré et al., C. R. Mecanique 336 (2008).

  6. Three-Dimensional Maximum-Quantum Correlation HMQC NMR Spectroscopy (3D MAXY-HMQC)

    NASA Astrophysics Data System (ADS)

    Liu, Maili; Mao, Xi-An; Ye, Chaohui; Nicholson, Jeremy K.; Lindon, John C.

    1997-11-01

    The extension of two-dimensional maximum-quantum correlation spectroscopy (2D MAXY NMR), which can be used to simplify complex NMR spectra, to three dimensions (3D) is described. A new pulse sequence for 3D MAXY-HMQC is presented and exemplified using the steroid drug dexamethasone. The sensitivity and coherence transfer efficiency of the MAXY NMR approach has also been assessed in relation to other HMQC- and HSQC-based 3D methods.

  7. Three-dimensional (3D) visualization of reflow porosity and modeling of deformation in Pb-free solder joints

    SciTech Connect

    Dudek, M.A.; Hunter, L.; Kranz, S.; Williams, J.J.; Lau, S.H.; Chawla, N.

    2010-04-15

    The volume, size, and dispersion of porosity in solder joints are known to affect mechanical performance and reliability. Most of the techniques used to characterize the three-dimensional (3D) nature of these defects are destructive. With the enhancements in high resolution computed tomography (CT), the detection limits of intrinsic microstructures have been significantly improved. Furthermore, the 3D microstructure of the material can be used in finite element models to understand their effect on microscopic deformation. In this paper we describe a technique utilizing high resolution (< 1 {mu}m) X-ray tomography for the three-dimensional (3D) visualization of pores in Sn-3.9Ag-0.7Cu/Cu joints. The characteristics of reflow porosity, including volume fraction and distribution, were investigated for two reflow profiles. The size and distribution of porosity size were visualized in 3D for four different solder joints. In addition, the 3D virtual microstructure was incorporated into a finite element model to quantify the effect of voids on the lap shear behavior of a solder joint. The presence, size, and location of voids significantly increased the severity of strain localization at the solder/copper interface.

  8. Accuracy of three-dimensional soft tissue prediction for Le Fort I osteotomy using Dolphin 3D software: a pilot study.

    PubMed

    Resnick, C M; Dang, R R; Glick, S J; Padwa, B L

    2017-03-01

    Three-dimensional (3D) soft tissue prediction is replacing two-dimensional analysis in planning for orthognathic surgery. The accuracy of different computational models to predict soft tissue changes in 3D, however, is unclear. A retrospective pilot study was implemented to assess the accuracy of Dolphin 3D software in making these predictions. Seven patients who had a single-segment Le Fort I osteotomy and had preoperative (T0) and >6-month postoperative (T1) cone beam computed tomography (CBCT) scans and 3D photographs were included. The actual skeletal change was determined by subtracting the T0 from the T1 CBCT. 3D photographs were overlaid onto the T0 CBCT and virtual skeletal movements equivalent to the achieved repositioning were applied using Dolphin 3D planner. A 3D soft tissue prediction (TP) was generated and differences between the TP and T1 images (error) were measured at 14 points and at the nasolabial angle. A mean linear prediction error of 2.91±2.16mm was found. The mean error at the nasolabial angle was 8.1±5.6°. In conclusion, the ability to accurately predict 3D soft tissue changes after Le Fort I osteotomy using Dolphin 3D software is limited.

  9. Three-Dimensional Integrated Circuit (3D IC) Key Technology: Through-Silicon Via (TSV).

    PubMed

    Shen, Wen-Wei; Chen, Kuan-Neng

    2017-12-01

    3D integration with through-silicon via (TSV) is a promising candidate to perform system-level integration with smaller package size, higher interconnection density, and better performance. TSV fabrication is the key technology to permit communications between various strata of the 3D integration system. TSV fabrication steps, such as etching, isolation, metallization processes, and related failure modes, as well as other characterizations are discussed in this invited review paper.

  10. Three-Dimensional Integrated Circuit (3D IC) Key Technology: Through-Silicon Via (TSV)

    NASA Astrophysics Data System (ADS)

    Shen, Wen-Wei; Chen, Kuan-Neng

    2017-01-01

    3D integration with through-silicon via (TSV) is a promising candidate to perform system-level integration with smaller package size, higher interconnection density, and better performance. TSV fabrication is the key technology to permit communications between various strata of the 3D integration system. TSV fabrication steps, such as etching, isolation, metallization processes, and related failure modes, as well as other characterizations are discussed in this invited review paper.

  11. Fully-coupled analysis of jet mixing problems. Three-dimensional PNS model, SCIP3D

    NASA Technical Reports Server (NTRS)

    Wolf, D. E.; Sinha, N.; Dash, S. M.

    1988-01-01

    Numerical procedures formulated for the analysis of 3D jet mixing problems, as incorporated in the computer model, SCIP3D, are described. The overall methodology closely parallels that developed in the earlier 2D axisymmetric jet mixing model, SCIPVIS. SCIP3D integrates the 3D parabolized Navier-Stokes (PNS) jet mixing equations, cast in mapped cartesian or cylindrical coordinates, employing the explicit MacCormack Algorithm. A pressure split variant of this algorithm is employed in subsonic regions with a sublayer approximation utilized for treating the streamwise pressure component. SCIP3D contains both the ks and kW turbulence models, and employs a two component mixture approach to treat jet exhausts of arbitrary composition. Specialized grid procedures are used to adjust the grid growth in accordance with the growth of the jet, including a hybrid cartesian/cylindrical grid procedure for rectangular jets which moves the hybrid coordinate origin towards the flow origin as the jet transitions from a rectangular to circular shape. Numerous calculations are presented for rectangular mixing problems, as well as for a variety of basic unit problems exhibiting overall capabilities of SCIP3D.

  12. Three-dimensional measurement of small inner surface profiles using feature-based 3-D panoramic registration

    NASA Astrophysics Data System (ADS)

    Gong, Yuanzheng; Seibel, Eric J.

    2017-01-01

    Rapid development in the performance of sophisticated optical components, digital image sensors, and computer abilities along with decreasing costs has enabled three-dimensional (3-D) optical measurement to replace more traditional methods in manufacturing and quality control. The advantages of 3-D optical measurement, such as noncontact, high accuracy, rapid operation, and the ability for automation, are extremely valuable for inline manufacturing. However, most of the current optical approaches are eligible for exterior instead of internal surfaces of machined parts. A 3-D optical measurement approach is proposed based on machine vision for the 3-D profile measurement of tiny complex internal surfaces, such as internally threaded holes. To capture the full topographic extent (peak to valley) of threads, a side-view commercial rigid scope is used to collect images at known camera positions and orientations. A 3-D point cloud is generated with multiview stereo vision using linear motion of the test piece, which is repeated by a rotation to form additional point clouds. Registration of these point clouds into a complete reconstruction uses a proposed automated feature-based 3-D registration algorithm. The resulting 3-D reconstruction is compared with x-ray computed tomography to validate the feasibility of our proposed method for future robotically driven industrial 3-D inspection.

  13. Three-dimensional measurement of small inner surface profiles using feature-based 3-D panoramic registration

    PubMed Central

    Gong, Yuanzheng; Seibel, Eric J.

    2017-01-01

    Rapid development in the performance of sophisticated optical components, digital image sensors, and computer abilities along with decreasing costs has enabled three-dimensional (3-D) optical measurement to replace more traditional methods in manufacturing and quality control. The advantages of 3-D optical measurement, such as noncontact, high accuracy, rapid operation, and the ability for automation, are extremely valuable for inline manufacturing. However, most of the current optical approaches are eligible for exterior instead of internal surfaces of machined parts. A 3-D optical measurement approach is proposed based on machine vision for the 3-D profile measurement of tiny complex internal surfaces, such as internally threaded holes. To capture the full topographic extent (peak to valley) of threads, a side-view commercial rigid scope is used to collect images at known camera positions and orientations. A 3-D point cloud is generated with multiview stereo vision using linear motion of the test piece, which is repeated by a rotation to form additional point clouds. Registration of these point clouds into a complete reconstruction uses a proposed automated feature-based 3-D registration algorithm. The resulting 3-D reconstruction is compared with x-ray computed tomography to validate the feasibility of our proposed method for future robotically driven industrial 3-D inspection. PMID:28286351

  14. Three-dimensional Printing and 3D Slicer: Powerful Tools in Understanding and Treating Structural Lung Disease.

    PubMed

    Cheng, George Z; San Jose Estepar, Raul; Folch, Erik; Onieva, Jorge; Gangadharan, Sidhu; Majid, Adnan

    2016-05-01

    Recent advances in the three-dimensional (3D) printing industry have enabled clinicians to explore the use of 3D printing in preprocedural planning, biomedical tissue modeling, and direct implantable device manufacturing. Despite the increased adoption of rapid prototyping and additive manufacturing techniques in the health-care field, many physicians lack the technical skill set to use this exciting and useful technology. Additionally, the growth in the 3D printing sector brings an ever-increasing number of 3D printers and printable materials. Therefore, it is important for clinicians to keep abreast of this rapidly developing field in order to benefit. In this Ahead of the Curve, we review the history of 3D printing from its inception to the most recent biomedical applications. Additionally, we will address some of the major barriers to wider adoption of the technology in the medical field. Finally, we will provide an initial guide to 3D modeling and printing by demonstrating how to design a personalized airway prosthesis via 3D Slicer. We hope this information will reduce the barriers to use and increase clinician participation in the 3D printing health-care sector.

  15. The performance & flow visualization studies of three-dimensional (3-D) wind turbine blade models

    NASA Astrophysics Data System (ADS)

    Sutrisno, Prajitno, Purnomo, W., Setyawan B.

    2016-06-01

    Recently, studies on the design of 3-D wind turbine blades have a less attention even though 3-D blade products are widely sold. In contrary, advanced studies in 3-D helicopter blade tip have been studied rigorously. Studies in wind turbine blade modeling are mostly assumed that blade spanwise sections behave as independent two-dimensional airfoils, implying that there is no exchange of momentum in the spanwise direction. Moreover, flow visualization experiments are infrequently conducted. Therefore, a modeling study of wind turbine blade with visualization experiment is needed to be improved to obtain a better understanding. The purpose of this study is to investigate the performance of 3-D wind turbine blade models with backward-forward swept and verify the flow patterns using flow visualization. In this research, the blade models are constructed based on the twist and chord distributions following Schmitz's formula. Forward and backward swept are added to the rotating blades. Based on this, the additional swept would enhance or diminish outward flow disturbance or stall development propagation on the spanwise blade surfaces to give better blade design. Some combinations, i. e., b lades with backward swept, provide a better 3-D favorable rotational force of the rotor system. The performance of the 3-D wind turbine system model is measured by a torque meter, employing Prony's braking system. Furthermore, the 3-D flow patterns around the rotating blade models are investigated by applying "tuft-visualization technique", to study the appearance of laminar, separated, and boundary layer flow patterns surrounding the 3-dimentional blade system.

  16. Acoustic Scattering by Three-Dimensional Stators and Rotors Using the SOURCE3D Code. Volume 1; Analysis and Results

    NASA Technical Reports Server (NTRS)

    Meyer, Harold D.

    1999-01-01

    This report provides a study of rotor and stator scattering using the SOURCE3D Rotor Wake/Stator Interaction Code. SOURCE3D is a quasi-three-dimensional computer program that uses three-dimensional acoustics and two-dimensional cascade load response theory to calculate rotor and stator modal reflection and transmission (scattering) coefficients. SOURCE3D is at the core of the TFaNS (Theoretical Fan Noise Design/Prediction System), developed for NASA, which provides complete fully coupled (inlet, rotor, stator, exit) noise solutions for turbofan engines. The reason for studying scattering is that we must first understand the behavior of the individual scattering coefficients provided by SOURCE3D, before eventually understanding the more complicated predictions from TFaNS. To study scattering, we have derived a large number of scattering curves for vane and blade rows. The curves are plots of output wave power divided by input wave power (in dB units) versus vane/blade ratio. Some of these plots are shown in this report. All of the plots are provided in a separate volume. To assist in understanding the plots, formulas have been derived for special vane/blade ratios for which wavefronts are either parallel or normal to rotor or stator chords. From the plots, we have found that, for the most part, there was strong transmission and weak reflection over most of the vane/blade ratio range for the stator. For the rotor, there was little transmission loss.

  17. User's manual for three dimensional boundary layer (BL3-D) code

    NASA Technical Reports Server (NTRS)

    Anderson, O. L.; Caplin, B.

    1985-01-01

    An assessment has been made of the applicability of a 3-D boundary layer analysis to the calculation of heat transfer, total pressure losses, and streamline flow patterns on the surface of both stationary and rotating turbine passages. In support of this effort, an analysis has been developed to calculate a general nonorthogonal surface coordinate system for arbitrary 3-D surfaces and also to calculate the boundary layer edge conditions for compressible flow using the surface Euler equations and experimental data to calibrate the method, calculations are presented for the pressure endwall, and suction surfaces of a stationary cascade and for the pressure surface of a rotating turbine blade. The results strongly indicate that the 3-D boundary layer analysis can give good predictions of the flow field, loss, and heat transfer on the pressure, suction, and endwall surface of a gas turbine passage.

  18. User's manual for three dimensional boundary layer (BL3-D) code

    NASA Astrophysics Data System (ADS)

    Anderson, O. L.; Caplin, B.

    1985-08-01

    An assessment has been made of the applicability of a 3-D boundary layer analysis to the calculation of heat transfer, total pressure losses, and streamline flow patterns on the surface of both stationary and rotating turbine passages. In support of this effort, an analysis has been developed to calculate a general nonorthogonal surface coordinate system for arbitrary 3-D surfaces and also to calculate the boundary layer edge conditions for compressible flow using the surface Euler equations and experimental data to calibrate the method, calculations are presented for the pressure endwall, and suction surfaces of a stationary cascade and for the pressure surface of a rotating turbine blade. The results strongly indicate that the 3-D boundary layer analysis can give good predictions of the flow field, loss, and heat transfer on the pressure, suction, and endwall surface of a gas turbine passage.

  19. Three-Dimensional Integrated Characterization and Archiving System (3D-ICAS). Phase 1

    SciTech Connect

    1994-07-01

    3D-ICAS is being developed to support Decontamination and Decommissioning operations for DOE addressing Research Area 6 (characterization) of the Program Research and Development Announcement. 3D-ICAS provides in-situ 3-dimensional characterization of contaminated DOE facilities. Its multisensor probe contains a GC/MS (gas chromatography/mass spectrometry using noncontact infrared heating) sensor for organics, a molecular vibrational sensor for base material identification, and a radionuclide sensor for radioactive contaminants. It will provide real-time quantitative measurements of volatile organics and radionuclides on bare materials (concrete, asbestos, transite); it will provide 3-D display of the fusion of all measurements; and it will archive the measurements for regulatory documentation. It consists of two robotic mobile platforms that operate in hazardous environments linked to an integrated workstation in a safe environment.

  20. 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

  1. Camera And Site Calibration For Three-Dimensional (3-D) Target Acquisition

    NASA Astrophysics Data System (ADS)

    Muzzy, William H...; Prell, Arthur M.; Shimp, Paul B.

    1982-02-01

    Three-dimensional target configurations attached to the head, neck, and pelvis of human volunteer subjects undergoing impact acceleration and vibration experiments are acquired by at least two cameras. Linear displacement and orientation parameters are derived from the digitized data film by a least squares algorithm. In order to minimize low frequency errors, it is necessary to calibrate individual high-speed cameras to determine points in the film plane. In addition, it is required to know how these cameras are located and oriented in the laboratory reference system. This paper will describe the procedure and the dedicated apparatus for camera calibration, discuss problems, and compare three surveying methods used to locate and determine camera orientation.

  2. Modeling Three-Dimensional Shock Initiation of PBX 9501 in ALE3D

    SciTech Connect

    Leininger, L; Springer, H K; Mace, J; Mas, E

    2008-07-08

    A recent SMIS (Specific Munitions Impact Scenario) experimental series performed at Los Alamos National Laboratory has provided 3-dimensional shock initiation behavior of the HMX-based heterogeneous high explosive, PBX 9501. A series of finite element impact calculations have been performed in the ALE3D [1] hydrodynamic code and compared to the SMIS results to validate and study code predictions. These SMIS tests used a powder gun to shoot scaled NATO standard fragments into a cylinder of PBX 9501, which has a PMMA case and a steel impact cover. This SMIS real-world shot scenario creates a unique test-bed because (1) SMIS tests facilitate the investigation of 3D Shock to Detonation Transition (SDT) within the context of a considerable suite of diagnostics, and (2) many of the fragments arrive at the impact plate off-center and at an angle of impact. A particular goal of these model validation experiments is to demonstrate the predictive capability of the ALE3D implementation of the Tarver-Lee Ignition and Growth reactive flow model [2] within a fully 3-dimensional regime of SDT. The 3-dimensional Arbitrary Lagrange Eulerian (ALE) hydrodynamic model in ALE3D applies the Ignition and Growth (I&G) reactive flow model with PBX 9501 parameters derived from historical 1-dimensional experimental data. The model includes the off-center and angle of impact variations seen in the experiments. Qualitatively, the ALE3D I&G calculations reproduce observed 'Go/No-Go' 3D Shock to Detonation Transition (SDT) reaction in the explosive, as well as the case expansion recorded by a high-speed optical camera. Quantitatively, the calculations show good agreement with the shock time of arrival at internal and external diagnostic pins. This exercise demonstrates the utility of the Ignition and Growth model applied for the response of heterogeneous high explosives in the SDT regime.

  3. Three-dimensional display modes for CT colonography: conventional 3D virtual colonoscopy versus unfolded cube projection.

    PubMed

    Vos, Frans M; van Gelder, Rogier E; Serlie, Iwo W O; Florie, Jasper; Nio, C Yung; Glas, Afina S; Post, Frits H; Truyen, Roel; Gerritsen, Frans A; Stoker, Jaap

    2003-09-01

    The authors compared a conventional two-directional three-dimensional (3D) display for computed tomography (CT) colonography with an alternative method they developed on the basis of time efficiency and surface visibility. With the conventional technique, 3D ante- and retrograde cine loops were obtained (hereafter, conventional 3D). With the alternative method, six projections were obtained at 90 degrees viewing angles (unfolded cube display). Mean evaluation time per patient with the conventional 3D display was significantly longer than that with the unfolded cube display. With the conventional 3D method, 93.8% of the colon surface came into view; with the unfolded cube method, 99.5% of the colon surface came into view. Sensitivity and specificity were not significantly different between the two methods. Agreements between observers were kappa = 0.605 for conventional 3D display and kappa = 0.692 for unfolded cube display. Consequently, the latter method enhances the 3D endoluminal display with improved time efficiency and higher surface visibility.

  4. 4-mm-diameter three-dimensional imaging endoscope with steerable camera for minimally invasive surgery (3-D-MARVEL).

    PubMed

    Bae, Sam Y; Korniski, Ronald J; Shearn, Michael; Manohara, Harish M; Shahinian, Hrayr

    2017-01-01

    High-resolution three-dimensional (3-D) imaging (stereo imaging) by endoscopes in minimally invasive surgery, especially in space-constrained applications such as brain surgery, is one of the most desired capabilities. Such capability exists at larger than 4-mm overall diameters. We report the development of a stereo imaging endoscope of 4-mm maximum diameter, called Multiangle, Rear-Viewing Endoscopic Tool (MARVEL) that uses a single-lens system with complementary multibandpass filter (CMBF) technology to achieve 3-D imaging. In addition, the system is endowed with the capability to pan from side-to-side over an angle of [Formula: see text], which is another unique aspect of MARVEL for such a class of endoscopes. The design and construction of a single-lens, CMBF aperture camera with integrated illumination to generate 3-D images, and the actuation mechanism built into it is summarized.

  5. Three dimensional surface analyses of pubic symphyseal faces of contemporary Japanese reconstructed with 3D digitized scanner.

    PubMed

    Biwasaka, Hitoshi; Sato, Kei; Aoki, Yasuhiro; Kato, Hideaki; Maeno, Yoshitaka; Tanijiri, Toyohisa; Fujita, Sachiko; Dewa, Koji

    2013-09-01

    Three dimensional pubic bone images were analyzed to quantify some age-dependent morphological changes of the symphyseal faces of contemporary Japanese residents. The images were synthesized from 145 bone specimens with 3D measuring device. Phases of Suchey-Brooks system were determined on the 3D pubic symphyseal images without discrepancy from those carried out on the real bones because of the high fidelity. Subsequently, mean curvatures of the pubic symphyseal faces to examine concavo-convex condition of the surfaces were analyzed on the 3D images. Average values of absolute mean curvatures of phase 1 and 2 groups were higher than those of phase 3-6 ones, whereas the values were approximately constant over phase 3 presumably reflecting the inactivation of pubic faces over phase 3. Ratio of the concave areas increased gradually with progressing phase or age classes, although convex areas were predominant in every phase.

  6. First intraoperative experience with three-dimensional (3D) high-definition (HD) nasal endoscopy for lacrimal surgeries.

    PubMed

    Ali, Mohammad Javed; Naik, Milind N

    2017-02-02

    The aim of this study is to report our preliminary experiences with regard to safety and feasibility of three-dimensional (3D) endoscopic lacrimal surgeries with a recently launched latest generation 3D endoscope. A 4-mm rigid three-dimensional (3D) endoscope (TIPCAM 1S 3D ORL(R), Karl Storz, Tuttlingen, Germany) was used. Fifteen patients who underwent various endoscopic lacrimal procedures by a single surgeon (MJA) were included. The procedures included probing with nasolacrimal intubation, cruciate marsupialization of intranasal cysts for congenital dacryoceles, powered endoscopic dacryocystorhinostomy, post-operative stent removal with ostium granuloma excision. The implementation, visualization, optical performance, ease of tissue handling and complications were noted. Ten surgical observers filled a questionnaire to rate their experiences. Enhanced depth perception was found to be very beneficial intraoperatively. Greater anatomical delineation facilitated improved hand-eye coordination and dexterity. Intraoperative assessment and handling of tissues and surgical manoeuvring were precise and did not require the additional spatial cues that the surgeon derives from a two-dimensional image. These benefits were more appreciated in the complex cases. The setup was easy on previous endoscopic platforms and did not consume any additional time. All the surgical procedures were completed successfully without any complications. The surgical observers unanimously noted enhanced anatomical understanding and surgical learning as compared to the routine 2D planes. Operating in 3D planes enhances depth perception, dexterity and precision. Although initial results are promising, further randomized studies with head-on comparisons between 3D and 2D would help formulate specific guidelines.

  7. Differences in growth properties of endometrial cancer in three dimensional (3D) culture and 2D cell monolayer

    SciTech Connect

    Chitcholtan, Kenny; Asselin, Eric; Parent, Sophie; Sykes, Peter H.; Evans, John J.

    2013-01-01

    Three-dimensional (3D) in vitro models have an invaluable role in understanding the behaviour of tumour cells in a well defined microenvironment. This is because some aspects of tumour characteristics cannot be fully recapitulated in a cell monolayer (2D). In the present study, we compared growth patterns, expression of signalling molecules, and metabolism-associated proteins of endometrial cancer cell lines in 3D and 2D cell cultures. Cancer cells formed spherical structures in 3D reconstituted basement membrane (3D rBM), and the morphological appearance was cell line dependent. Cell differentiation was observed after 8 days in the 3D rBM. There was reduced proliferation, detected by less expression of PCNA in 3D rBM than in 2D cell monolayers. The addition of exogenous epidermal growth factor (EGF) to cancer cells induced phosphorylation of EGFR and Akt in both cell culture conditions. The uptake of glucose was selectively altered in the 3D rBM, but there was a lack of association with Glut-1 expression. The secretion of vascular endothelial growth factor (VEGF) and prostaglandin E{sub 2} (PGE{sub 2}) was selectively altered in 3D rBM, and it was cell line dependent. Our data demonstrated that 3D rBM as an in vitro model can influence proliferation and metabolism of endometrial cancer cell behaviour compared to 2D cell monolayer. Changes are specific to individual cell types. The use of 3D rBM is, therefore, important in the in vitro study of targeted anticancer therapies.

  8. A diffuser-based three-dimensional measurement of polarization-dependent scattering characteristics of optical films for 3D-display applications.

    PubMed

    Kim, Dae-Yeon; Seo, Jong-Wook

    2015-01-26

    We propose an accurate and easy-to-use three-dimensional measurement method using a diffuser plate to analyze the scattering characteristics of optical films. The far-field radiation pattern of light scattered by the optical film is obtained from the illuminance pattern created on the diffuser plate by the light. A mathematical model and calibration methods were described, and the results were compared with those obtained by a direct measurement using a luminance meter. The new method gave very precise three-dimensional polarization-dependent scattering characteristics of scattering polarizer films, and it can play an effective role in developing high performance polarization-selective screens for 3D display applications.

  9. Computer-assisted three-dimensional surgical planning: 3D virtual articulator: technical note.

    PubMed

    Ghanai, S; Marmulla, R; Wiechnik, J; Mühling, J; Kotrikova, B

    2010-01-01

    This study presents a computer-assisted planning system for dysgnathia treatment. It describes the process of information gathering using a virtual articulator and how the splints are constructed for orthognathic surgery. The deviation of the virtually planned splints is shown in six cases on the basis of conventionally planned cases. In all cases the plaster models were prepared and scanned using a 3D laser scanner. Successive lateral and posterior-anterior cephalometric images were used for reconstruction before surgery. By identifying specific points on the X-rays and marking them on the virtual models, it was possible to enhance the 2D images to create a realistic 3D environment and to perform virtual repositioning of the jaw. A hexapod was used to transfer the virtual planning to the real splints. Preliminary results showed that conventional repositioning could be replicated using the virtual articulator.

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

    SciTech Connect

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

    1981-11-01

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

  11. IDA3D: An Ionospheric Data Assimilative Three Dimensional Tomography Processor

    DTIC Science & Technology

    2001-09-30

    region electron densities, it can contribute important spatial and temporal information to the Joule heating at high latitudes. Figure 2: 2D...using the Greenland tomography data with IDA3D to investigate E-region electron densities and the related Joule heating effects. • Alaska...for long term monitoring of the Alaska ionosphere in support of HAARP activities and to do scientific studies of neutral wind coupling to the

  12. Incorporating Digisonde Traces into the Ionospheric Data Assimilation Three Dimensional (IDA3D) Algorithm

    DTIC Science & Technology

    2006-05-11

    digisonde data, two days of data from the Digital Ionogram DataBase (http://ulcar.uml.edu/DIDBase/), the largest digisonde database, were visually...examined. These data were processed by the Automatic Real Time Ionogram Scaler with True Height (ARTIST) [Reinisch and Huang, 1983] program into electron... ionograms are available for comparison. The first test run of the IDA3D used only O-mode autoscaled virtual height profiles from five different digisondes

  13. Automated three-dimensional choroidal vessel segmentation of 3D 1060 nm OCT retinal data

    PubMed Central

    Kajić, Vedran; Esmaeelpour, Marieh; Glittenberg, Carl; Kraus, Martin F.; Honegger, Joachim; Othara, Richu; Binder, Susanne; Fujimoto, James G.; Drexler, Wolfgang

    2012-01-01

    A fully automated, robust vessel segmentation algorithm has been developed for choroidal OCT, employing multiscale 3D edge filtering and projection of “probability cones” to determine the vessel “core”, even in the tomograms with low signal-to-noise ratio (SNR). Based on the ideal vessel response after registration and multiscale filtering, with computed depth related SNR, the vessel core estimate is dilated to quantify the full vessel diameter. As a consequence, various statistics can be computed using the 3D choroidal vessel information, such as ratios of inner (smaller) to outer (larger) choroidal vessels or the absolute/relative volume of choroid vessels. Choroidal vessel quantification can be displayed in various forms, focused and averaged within a special region of interest, or analyzed as the function of image depth. In this way, the proposed algorithm enables unique visualization of choroidal watershed zones, as well as the vessel size reduction when investigating the choroid from the sclera towards the retinal pigment epithelium (RPE). To the best of our knowledge, this is the first time that an automatic choroidal vessel segmentation algorithm is successfully applied to 1060 nm 3D OCT of healthy and diseased eyes. PMID:23304653

  14. Accuracy and precision of the three-dimensional assessment of the facial surface using a 3-D laser scanner.

    PubMed

    Kovacs, L; Zimmermann, A; Brockmann, G; Baurecht, H; Schwenzer-Zimmerer, K; Papadopulos, N A; Papadopoulos, M A; Sader, R; Biemer, E; Zeilhofer, H F

    2006-06-01

    Three-dimensional (3-D) recording of the surface of the human body or anatomical areas has gained importance in many medical specialties. Thus, it is important to determine scanner precision and accuracy in defined medical applications and to establish standards for the recording procedure. Here we evaluated the precision and accuracy of 3-D assessment of the facial area with the Minolta Vivid 910 3D Laser Scanner. We also investigated the influence of factors related to the recording procedure and the processing of scanner data on final results. These factors include lighting, alignment of scanner and object, the examiner, and the software used to convert measurements into virtual images. To assess scanner accuracy, we compared scanner data to those obtained by manual measurements on a dummy. Less than 7% of all results with the scanner method were outside a range of error of 2 mm when compared to corresponding reference measurements. Accuracy, thus, proved to be good enough to satisfy requirements for numerous clinical applications. Moreover, the experiments completed with the dummy yielded valuable information for optimizing recording parameters for best results. Thus, under defined conditions, precision and accuracy of surface models of the human face recorded with the Minolta Vivid 910 3D Scanner presumably can also be enhanced. Future studies will involve verification of our findings using test persons. The current findings indicate that the Minolta Vivid 910 3D Scanner might be used with benefit in medicine when recording the 3-D surface structures of the face.

  15. DYNA3D: A nonlinear, explicit, three-dimensional finite element code for solid and structural mechanics, User manual. Revision 1

    SciTech Connect

    Whirley, R.G.; Engelmann, B.E.

    1993-11-01

    This report is the User Manual for the 1993 version of DYNA3D, and also serves as a User Guide. DYNA3D is a nonlinear, explicit, finite element code for analyzing the transient dynamic response of three-dimensional solids and structures. The code is fully vectorized and is available on several computer platforms. DYNA3D includes solid, shell, beam, and truss elements to allow maximum flexibility in modeling physical problems. Many material models are available to represent a wide range of material behavior, including elasticity, plasticity, composites, thermal effects, and rate dependence. In addition, DYNA3D has a sophisticated contact interface capability, including frictional sliding and single surface contact. Rigid materials provide added modeling flexibility. A material model driver with interactive graphics display is incorporated into DYNA3D to permit accurate modeling of complex material response based on experimental data. Along with the DYNA3D Example Problem Manual, this document provides the information necessary to apply DYNA3D to solve a wide range of engineering analysis problems.

  16. 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.

  17. Three-dimensional inelastic analysis for hot section components, BEST 3D code

    NASA Technical Reports Server (NTRS)

    Wilson, Raymond B.; Banerjee, Prasanta K.

    1987-01-01

    The goal is the development of an alternative stress analysis tool, distinct from the finite element method, applicable to the engineering analysis of gas turbine engine structures. The boundary element method was selected for this development effort on the basis of its already demonstrated applicability to a variety of geometries and problem types characteristic of gas turbine engine components. Major features of the BEST3D computer program are described, and some of the significant developments carried out as part of the Inelastic Methods Contract are outlined.

  18. A Three Dimensional Parallel Time Accurate Turbopump Simulation Procedure Using Overset Grid Systems

    NASA Technical Reports Server (NTRS)

    Kiris, Cetin; Chan, William; Kwak, Dochan

    2001-01-01

    The objective of the current effort is to provide a computational framework for design and analysis of the entire fuel supply system of a liquid rocket engine, including high-fidelity unsteady turbopump flow analysis. This capability is needed to support the design of pump sub-systems for advanced space transportation vehicles that are likely to involve liquid propulsion systems. To date, computational tools for design/analysis of turbopump flows are based on relatively lower fidelity methods. An unsteady, three-dimensional viscous flow analysis tool involving stationary and rotational components for the entire turbopump assembly has not been available for real-world engineering applications. The present effort provides developers with information such as transient flow phenomena at start up, and non-uniform inflows, and will eventually impact on system vibration and structures. In the proposed paper, the progress toward the capability of complete simulation of the turbo-pump for a liquid rocket engine is reported. The Space Shuttle Main Engine (SSME) turbo-pump is used as a test case for evaluation of the hybrid MPI/Open-MP and MLP versions of the INS3D code. CAD to solution auto-scripting capability is being developed for turbopump applications. The relative motion of the grid systems for the rotor-stator interaction was obtained using overset grid techniques. Unsteady computations for the SSME turbo-pump, which contains 114 zones with 34.5 million grid points, are carried out on Origin 3000 systems at NASA Ames Research Center. Results from these time-accurate simulations with moving boundary capability will be presented along with the performance of parallel versions of the code.

  19. A Three-Dimensional Parallel Time-Accurate Turbopump Simulation Procedure Using Overset Grid System

    NASA Technical Reports Server (NTRS)

    Kiris, Cetin; Chan, William; Kwak, Dochan

    2002-01-01

    The objective of the current effort is to provide a computational framework for design and analysis of the entire fuel supply system of a liquid rocket engine, including high-fidelity unsteady turbopump flow analysis. This capability is needed to support the design of pump sub-systems for advanced space transportation vehicles that are likely to involve liquid propulsion systems. To date, computational tools for design/analysis of turbopump flows are based on relatively lower fidelity methods. An unsteady, three-dimensional viscous flow analysis tool involving stationary and rotational components for the entire turbopump assembly has not been available for real-world engineering applications. The present effort provides developers with information such as transient flow phenomena at start up, and nonuniform inflows, and will eventually impact on system vibration and structures. In the proposed paper, the progress toward the capability of complete simulation of the turbo-pump for a liquid rocket engine is reported. The Space Shuttle Main Engine (SSME) turbo-pump is used as a test case for evaluation of the hybrid MPI/Open-MP and MLP versions of the INS3D code. CAD to solution auto-scripting capability is being developed for turbopump applications. The relative motion of the grid systems for the rotor-stator interaction was obtained using overset grid techniques. Unsteady computations for the SSME turbo-pump, which contains 114 zones with 34.5 million grid points, are carried out on Origin 3000 systems at NASA Ames Research Center. Results from these time-accurate simulations with moving boundary capability are presented along with the performance of parallel versions of the code.

  20. The Three-Dimensional (3D) Numerical Stability Analysis of Hyttemalmen Open-Pit

    NASA Astrophysics Data System (ADS)

    Cała, Marek; Kowalski, Michał; Stopkowicz, Agnieszka

    2014-10-01

    The purpose of this paper was to perform the 3D numerical calculations allowing slope stability analysis of Hyttemalmen open pit (location Kirkenes, Finnmark Province, Norway). After a ramp rock slide, which took place in December 2010, as well as some other small-scale rock slope stability problems, it proved necessary to perform a serious stability analyses. The Hyttemalmen open pit was designed with a depth up to 100 m, a bench height of 24 m and a ramp width of 10 m. The rock formation in the iron mining district of Kirkenes is called the Bjornevaten Group. This is the most structurally complicated area connected with tectonic process such as folding, faults and metamorphosis. The Bjornevaten Group is a volcano-sedimentary sequence. Rock slope stability depends on the mechanical properties of the rock, hydro-geological conditions, slope topography, joint set systems and seismic activity. However, rock slope stability is mainly connected with joint sets. Joints, or general discontinuities, are regarded as weak planes within rock which have strength reducing consequences with regard to rock strength. Discontinuities within the rock mass lead to very low tensile strength. Several simulations were performed utilising the RocLab (2007) software to estimate the gneiss cohesion for slopes of different height. The RocLab code is dedicated to estimate rock mass strength using the Hoek-Brown failure criterion. Utilising both the GSI index and the Hoek-Brown strength criterion the equivalent Mohr-Coulomb parameters (cohesion and angle of internal friction) can be calculated. The results of 3D numerical calculations (with FLA3D code) show that it is necessary to redesign the slope-bench system in the Hyttemalmen open pit. Changing slope inclination for lower stages is recommended. The minimum factor of safety should be equal 1.3. At the final planned stage of excavation, the factor of safety drops to 1.06 with failure surface ranging through all of the slopes. In the case

  1. Noncontrast-enhanced three-dimensional (3D) intracranial MR angiography using pseudocontinuous arterial spin labeling and accelerated 3D radial acquisition.

    PubMed

    Wu, Huimin; Block, Walter F; Turski, Patrick A; Mistretta, Charles A; Johnson, Kevin M

    2013-03-01

    Pseudocontinuous arterial spin labeling (PCASL) can be used to generate noncontrast magnetic resonance angiograms of the cerebrovascular structures. Previously described PCASL-based angiography techniques were limited to two-dimensional projection images or relatively low-resolution three-dimensional (3D) imaging due to long acquisition time. This work proposes a new PCASL-based 3D magnetic resonance angiography method that uses an accelerated 3D radial acquisition technique (VIPR, spoiled gradient echo) as the readout. Benefiting from the sparsity provided by PCASL and noise-like artifacts of VIPR, this new method is able to obtain submillimeter 3D isotropic resolution and whole head coverage with a 8-min scan. Intracranial angiography feasibility studies in healthy (N = 5) and diseased (N = 5) subjects show reduced saturation artifacts in PCASL-VIPR compared with a standard time-of-flight protocol. These initial results show great promise for PCASL-VIPR for static, dynamic, and vessel selective 3D intracranial angiography.

  2. Using subject-specific three-dimensional (3D) anthropometry data in digital human modelling: case study in hand motion simulation.

    PubMed

    Tsao, Liuxing; Ma, Liang

    2016-11-01

    Digital human modelling enables ergonomists and designers to consider ergonomic concerns and design alternatives in a timely and cost-efficient manner in the early stages of design. However, the reliability of the simulation could be limited due to the percentile-based approach used in constructing the digital human model. To enhance the accuracy of the size and shape of the models, we proposed a framework to generate digital human models using three-dimensional (3D) anthropometric data. The 3D scan data from specific subjects' hands were segmented based on the estimated centres of rotation. The segments were then driven in forward kinematics to perform several functional postures. The constructed hand models were then verified, thereby validating the feasibility of the framework. The proposed framework helps generate accurate subject-specific digital human models, which can be utilised to guide product design and workspace arrangement. Practitioner Summary: Subject-specific digital human models can be constructed under the proposed framework based on three-dimensional (3D) anthropometry. This approach enables more reliable digital human simulation to guide product design and workspace arrangement.

  3. 3D FaceCam: a fast and accurate 3D facial imaging device for biometrics applications

    NASA Astrophysics Data System (ADS)

    Geng, Jason; Zhuang, Ping; May, Patrick; Yi, Steven; Tunnell, David

    2004-08-01

    Human faces are fundamentally three-dimensional (3D) objects, and each face has its unique 3D geometric profile. The 3D geometric features of a human face can be used, together with its 2D texture, for rapid and accurate face recognition purposes. Due to the lack of low-cost and robust 3D sensors and effective 3D facial recognition (FR) algorithms, almost all existing FR systems use 2D face images. Genex has developed 3D solutions that overcome the inherent problems in 2D while also addressing limitations in other 3D alternatives. One important aspect of our solution is a unique 3D camera (the 3D FaceCam) that combines multiple imaging sensors within a single compact device to provide instantaneous, ear-to-ear coverage of a human face. This 3D camera uses three high-resolution CCD sensors and a color encoded pattern projection system. The RGB color information from each pixel is used to compute the range data and generate an accurate 3D surface map. The imaging system uses no moving parts and combines multiple 3D views to provide detailed and complete 3D coverage of the entire face. Images are captured within a fraction of a second and full-frame 3D data is produced within a few seconds. This described method provides much better data coverage and accuracy in feature areas with sharp features or details (such as the nose and eyes). Using this 3D data, we have been able to demonstrate that a 3D approach can significantly improve the performance of facial recognition. We have conducted tests in which we have varied the lighting conditions and angle of image acquisition in the "field." These tests have shown that the matching results are significantly improved when enrolling a 3D image rather than a single 2D image. With its 3D solutions, Genex is working toward unlocking the promise of powerful 3D FR and transferring FR from a lab technology into a real-world biometric solution.

  4. VIRO 3D: fast three-dimensional full-body scanning for humans and other living objects

    NASA Astrophysics Data System (ADS)

    Stein, Norbert; Minge, Bernhard

    1998-03-01

    The development of a family of partial and whole body scanners provides a complete technology for fully three-dimensional and contact-free scans on human bodies or other living objects within seconds. This paper gives insight into the design and the functional principles of the whole body scanner VIRO 3D operating on the basis of the laser split-beam method. The arrangement of up to 24 camera/laser combinations, thus dividing the area into different camera fields and an all- around sensor configuration travelling in vertical direction allow the complete 360-degree-scan of an object within 6 - 20 seconds. Due to a special calibration process the different sensors are matched and the measured data are combined. Up to 10 million 3D measuring points with a resolution of approximately 1 mm are processed in all coordinate axes to generate a 3D model. By means of high-performance processors in combination with real-time image processing chips the image data from almost any number of sensors can be recorded and evaluated synchronously in video real-time. VIRO 3D scanning systems have already been successfully implemented in various applications and will open up new perspectives in different other fields, ranging from industry, orthopaedic medicine, plastic surgery to art and photography.

  5. Predicting Subtype Selectivity for Adenosine Receptor Ligands with Three-Dimensional Biologically Relevant Spectrum (BRS-3D)

    PubMed Central

    He, Song-Bing; Ben Hu; Kuang, Zheng-Kun; Wang, Dong; Kong, De-Xin

    2016-01-01

    Adenosine receptors (ARs) are potential therapeutic targets for Parkinson’s disease, diabetes, pain, stroke and cancers. Prediction of subtype selectivity is therefore important from both therapeutic and mechanistic perspectives. In this paper, we introduced a shape similarity profile as molecular descriptor, namely three-dimensional biologically relevant spectrum (BRS-3D), for AR selectivity prediction. Pairwise regression and discrimination models were built with the support vector machine methods. The average determination coefficient (r2) of the regression models was 0.664 (for test sets). The 2B-3 (A2B vs A3) model performed best with q2 = 0.769 for training sets (10-fold cross-validation), and r2 = 0.766, RMSE = 0.828 for test sets. The models’ robustness and stability were validated with 100 times resampling and 500 times Y-randomization. We compared the performance of BRS-3D with 3D descriptors calculated by MOE. BRS-3D performed as good as, or better than, MOE 3D descriptors. The performances of the discrimination models were also encouraging, with average accuracy (ACC) 0.912 and MCC 0.792 (test set). The 2A-3 (A2A vs A3) selectivity discrimination model (ACC = 0.882 and MCC = 0.715 for test set) outperformed an earlier reported one (ACC = 0.784). These results demonstrated that, through multiple conformation encoding, BRS-3D can be used as an effective molecular descriptor for AR subtype selectivity prediction. PMID:27812030

  6. Predicting Subtype Selectivity for Adenosine Receptor Ligands with Three-Dimensional Biologically Relevant Spectrum (BRS-3D)

    NASA Astrophysics Data System (ADS)

    He, Song-Bing; Ben Hu; Kuang, Zheng-Kun; Wang, Dong; Kong, De-Xin

    2016-11-01

    Adenosine receptors (ARs) are potential therapeutic targets for Parkinson’s disease, diabetes, pain, stroke and cancers. Prediction of subtype selectivity is therefore important from both therapeutic and mechanistic perspectives. In this paper, we introduced a shape similarity profile as molecular descriptor, namely three-dimensional biologically relevant spectrum (BRS-3D), for AR selectivity prediction. Pairwise regression and discrimination models were built with the support vector machine methods. The average determination coefficient (r2) of the regression models was 0.664 (for test sets). The 2B-3 (A2B vs A3) model performed best with q2 = 0.769 for training sets (10-fold cross-validation), and r2 = 0.766, RMSE = 0.828 for test sets. The models’ robustness and stability were validated with 100 times resampling and 500 times Y-randomization. We compared the performance of BRS-3D with 3D descriptors calculated by MOE. BRS-3D performed as good as, or better than, MOE 3D descriptors. The performances of the discrimination models were also encouraging, with average accuracy (ACC) 0.912 and MCC 0.792 (test set). The 2A-3 (A2A vs A3) selectivity discrimination model (ACC = 0.882 and MCC = 0.715 for test set) outperformed an earlier reported one (ACC = 0.784). These results demonstrated that, through multiple conformation encoding, BRS-3D can be used as an effective molecular descriptor for AR subtype selectivity prediction.

  7. Accurate, full-chip, three-dimensional electromagnetic field model for non-Manhattan mask corners

    NASA Astrophysics Data System (ADS)

    Lam, Michael C.; Clifford, Chris; Oliver, Mike; Fryer, David; Tejnil, Edita; Adam, Kostas

    2016-04-01

    The physical process of mask manufacturing produces absorber geometry with significant deviations from the 90-deg corners, which are typically assumed in the mask design. The non-Manhattan mask geometry is an essential contributor to the aerial image and resulting patterning performance through focus. Current state-of-the-art models for corner rounding employ "chopping" a 90-deg mask corner, replacing the corner with a small 45-deg edge. A methodology is presented to approximate the impact of three-dimensional (3-D) EMF effects introduced by corners with rounded edges. The approach is integrated into a full-chip 3-D mask simulation methodology based on the domain decomposition method with edge to edge crosstalk correction.

  8. Towards an easier creation of three-dimensional data for embedding into scholarly 3D PDF (Portable Document Format) files

    PubMed Central

    2015-01-01

    The Portable Document Format (PDF) allows for embedding three-dimensional (3D) models and is therefore particularly suitable to communicate respective data, especially as regards scholarly articles. The generation of the necessary model data, however, is still challenging, especially for inexperienced users. This prevents an unrestrained proliferation of 3D PDF usage in scholarly communication. This article introduces a new solution for the creation of three of types of 3D geometry (point clouds, polylines and triangle meshes), that is based on MeVisLab, a framework for biomedical image processing. This solution enables even novice users to generate the model data files without requiring programming skills and without the need for an intensive training by simply using it as a conversion tool. Advanced users can benefit from the full capability of MeVisLab to generate and export the model data as part of an overall processing chain. Although MeVisLab is primarily designed for handling biomedical image data, the new module is not restricted to this domain. It can be used for all scientific disciplines. PMID:25780759

  9. Adaptation of the three-dimensional wisdom scale (3D-WS) for the Korean cultural context.

    PubMed

    Kim, Seungyoun; Knight, Bob G

    2014-10-23

    ABSTRACT Background: Previous research on wisdom has suggested that wisdom is comprised of cognitive, reflective, and affective components and has developed and validated wisdom measures based on samples from Western countries. To apply the measurement to Eastern cultures, the present study revised an existing wisdom scale, the three-dimensional wisdom scale (3D-WS, Ardelt, 2003) for the Korean cultural context. Methods: Participants included 189 Korean heritage adults (age range 19-96) living in Los Angeles. We added a culturally specific factor of wisdom to the 3D-WS: Modesty and Unobtrusiveness (Yang, 2001), which captures an Eastern aspect of wisdom. The structure and psychometrics of the scale were tested. By latent cluster analysis, we determined acculturation subgroups and examined group differences in the means of factors in the revised wisdom scale (3D-WS-K). Results: Three factors, Cognitive Flexibility, Viewpoint Relativism, and Empathic Modesty were found using confirmatory factor analysis. Respondents with high biculturalism were higher on Viewpoint Relativism and lower on Empathic Modesty. Conclusion: This study discovered that a revised wisdom scale had a distinct factor structure and item content in a Korean heritage sample. We also found acculturation influences on the meaning of wisdom.

  10. A dual-frequency fringe projection three-dimensional shape measurement system using a DLP 3D projector

    NASA Astrophysics Data System (ADS)

    Dai, Meiling; Yang, Fujun; Liu, Cong; He, Xiaoyuan

    2017-01-01

    A dual-frequency fringe projection system for three-dimensional (3D) surface shape measurement is proposed in this paper. The system includes two cameras, a DLP 3D projector, and a liquid crystal (LC) shutter glasses. The phase information related to the object height is obtained from the dual-frequency temporal method with 3-step phase-shifting algorithm. By using the DLP 3D projector and LC shutter glasses, 3-step phase-shifting high-frequency and low-frequency fringe patterns are captured only 3 times by the two cameras synchronously. The technique of image registration is applied to low-frequency fringe patterns to guarantee the accuracy of low-frequency phase for high-frequency phase unwrapping. Using the equi-phase coordinate method based on two reference planes, the phase-to-height conversion and non-sinusoidal errors reduction are carried out in one go without any extra operation or measurement time. Experimental results demonstrate that the proposed method effectively improves the measuring speed, and it is valid for measuring surface shapes with multi-steps or discontinuities.

  11. Three Dimensional Rover/Lander/Orbiter Mission-Planning (3D-ROMPS) System: A Modern Approach to Mission Planning

    NASA Technical Reports Server (NTRS)

    Scharfe, Nathan D.

    2005-01-01

    NASA's current mission planning system is based on point design, two-dimensional display, spread sheets, and report technology. This technology does not enable engineers to analyze the results of parametric studies of missions plans. This technology will not support the increased observational complexity and data volume of missions like Cassini, Mars Reconnaissance Orbiter (MRO), Mars Science Laboratory (MSL), and Mars Sample Return (MSR). The goal of the 3D-ROMPS task has been to establish a set of operational mission planning and analysis tools in the Image Processing Laboratory (IPL) Mission Support Area (MSA) that will respond to engineering requirements for planning future Solar System Exploration (SSE) missions using a three-dimensional display.

  12. Identifying cell and molecular stress after radiation in a three-dimensional (3-D) model of oral mucositis

    SciTech Connect

    Lambros, Maria Polikandritou; Parsa, Cyrus; Mulamalla, HariChandana; Orlando, Robert; Lau, Bernard; Huang, Ying; Pon, Doreen; Chow, Moses

    2011-02-04

    Research highlights: {yields} We irradiated a 3-D human oral cell culture of keratinocytes and fibroblasts with 12 and 2 Gy. {yields} 6 h after irradiation the histopathology and apoptosis of the 3-D culture were evaluated. Microarrays were used to assess the gene expression in the irradiated 3-D tissue. {yields} 12 Gy induced significant histopathologic changes and cellular apoptosis. {yields} 12 Gy significantly affected genes of the NF-kB pathway, inflammatory cytokines and DAMPs. -- Abstract: Mucositis is a debilitating adverse effect of chemotherapy and radiation treatment. It is important to develop a simple and reliable in vitro model, which can routinely be used to screen new drugs for prevention and treatment of mucositis. Furthermore, identifying cell and molecular stresses especially in the initiation phase of mucositis in this model will help towards this end. We evaluated a three-dimensional (3-D) human oral cell culture that consisted of oral keratinocytes and fibroblasts as a model of oral mucositis. The 3-D cell culture model was irradiated with 12 or 2 Gy. Six hours after the irradiation we evaluated microscopic sections of the cell culture for evidence of morphologic changes including apoptosis. We used microarrays to compare the expression of several genes from the irradiated tissue with identical genes from tissue that was not irradiated. We found that irradiation with 12 Gy induced significant histopathologic effects including cellular apoptosis. Irradiation significantly affected the expression of several genes of the NF-kB pathway and several inflammatory cytokines, such as IL-1B, 1L-8, NF-kB1, and FOS compared to tissue that was not irradiated. We identified significant upregulation of several genes that belong to damage-associated molecular patterns (DAMPs) such as HMB1, S100A13, SA10014, and SA10016 in the 3-D tissues that received 12 Gy but not in tissues that received 2 Gy. In conclusion, this model quantifies radiation damage and this

  13. Accurate landmarking of three-dimensional facial data in the presence of facial expressions and occlusions using a three-dimensional statistical facial feature model.

    PubMed

    Zhao, Xi; Dellandréa, Emmanuel; Chen, Liming; Kakadiaris, Ioannis A

    2011-10-01

    Three-dimensional face landmarking aims at automatically localizing facial landmarks and has a wide range of applications (e.g., face recognition, face tracking, and facial expression analysis). Existing methods assume neutral facial expressions and unoccluded faces. In this paper, we propose a general learning-based framework for reliable landmark localization on 3-D facial data under challenging conditions (i.e., facial expressions and occlusions). Our approach relies on a statistical model, called 3-D statistical facial feature model, which learns both the global variations in configurational relationships between landmarks and the local variations of texture and geometry around each landmark. Based on this model, we further propose an occlusion classifier and a fitting algorithm. Results from experiments on three publicly available 3-D face databases (FRGC, BU-3-DFE, and Bosphorus) demonstrate the effectiveness of our approach, in terms of landmarking accuracy and robustness, in the presence of expressions and occlusions.

  14. Identifying cell and molecular stress after radiation in a three-dimensional (3-D) model of oral mucositis.

    PubMed

    Lambros, Maria Polikandritou; Parsa, Cyrus; Mulamalla, HariChandana; Orlando, Robert; Lau, Bernard; Huang, Ying; Pon, Doreen; Chow, Moses

    2011-02-04

    Mucositis is a debilitating adverse effect of chemotherapy and radiation treatment. It is important to develop a simple and reliable in vitro model, which can routinely be used to screen new drugs for prevention and treatment of mucositis. Furthermore, identifying cell and molecular stresses especially in the initiation phase of mucositis in this model will help towards this end. We evaluated a three-dimensional (3-D) human oral cell culture that consisted of oral keratinocytes and fibroblasts as a model of oral mucositis. The 3-D cell culture model was irradiated with 12 or 2 Gy. Six hours after the irradiation we evaluated microscopic sections of the cell culture for evidence of morphologic changes including apoptosis. We used microarrays to compare the expression of several genes from the irradiated tissue with identical genes from tissue that was not irradiated. We found that irradiation with 12 Gy induced significant histopathologic effects including cellular apoptosis. Irradiation significantly affected the expression of several genes of the NF-kB pathway and several inflammatory cytokines, such as IL-1B, 1L-8, NF-kB1, and FOS compared to tissue that was not irradiated. We identified significant upregulation of several genes that belong to damage-associated molecular patterns (DAMPs) such as HMB1, S100A13, SA10014, and SA10016 in the 3-D tissues that received 12 Gy but not in tissues that received 2 Gy. In conclusion, this model quantifies radiation damage and this is an important first step towards the development 3-D tissue as a screening tool.

  15. iBem3D, a three-dimensional iterative boundary element method using angular dislocations for modeling geologic structures

    NASA Astrophysics Data System (ADS)

    Maerten, F.; Maerten, L.; Pollard, D. D.

    2014-11-01

    Most analytical solutions to engineering or geological problems are limited to simple geometries. For example, analytical solutions have been found to solve for stresses around a circular hole in a plate. To solve more complex problems, mathematicians and engineers have developed powerful computer-aided numerical methods, which can be categorized into two main types: differential methods and integral methods. The finite element method (FEM) is a differential method that was developed in the 1950s and is one of the most commonly used numerical methods today. Since its development, other differential methods, including the boundary element method (BEM), have been developed to solve different types of problems. The purpose of this paper is to describe iBem3D, formally called Poly3D, a C++ and modular 3D boundary element computer program based on the theory of angular dislocations for modeling three-dimensional (3D) discontinuities in an elastic, heterogeneous, isotropic whole- or half-space. After 20 years and more than 150 scientific publications, we present in detail the formulation behind this method, its enhancements over the years as well as some important applications in several domains of the geosciences. The main advantage of using this formulation, for describing geological objects such as faults, resides in the possibility of modeling complex geometries without gaps and overlaps between adjacent triangular dislocation elements, which is a significant shortcoming for models using rectangular dislocation elements. Reliability, speed, simplicity, and accuracy are enhanced in the latest version of the computer code. Industrial applications include subseismic fault modeling, fractured reservoir modeling, interpretation and validation of fault connectivity and reservoir compartmentalization, depleted area and fault reactivation, and pressurized wellbore stability. Academic applications include earthquake and volcano monitoring, hazard mitigation, and slope

  16. Innovative three-dimensional (3D) eco-TiO2 photocatalysts for practical environmental and bio-medical applications

    PubMed Central

    Lee, Hyun Uk; Lee, Soon Chang; Lee, Young-Chul; Son, Byoungchul; Park, So Young; Lee, Jae Won; Oh, You-Kwan; Kim, Yooseok; Choi, Saehae; Lee, Young-Seak; Lee, Jouhahn

    2014-01-01

    It is known that water purified by conventional TiO2 photocatalysts may not be safe enough for drinking, due to the toxicity by tiny existence of TiO2 nanoparticles after water treatment. We herein demonstrate a facile design of a three-dimensional (3D) TiO2 photocatalyst structure with which both the efficiency of purification and the safety level of the final purified water can be improved and ensured, respectively. The structure, consisting of 3D sulfur-doped TiO2 microtubes in nanotubes (eco-TiO2), is suitable for both environmental and bio-medical applications. Investigation of its formation mechanism reveals that anodic aluminum oxide (AAO), owing to a spatial constraint, causes a simple, nanoparticles-to-nanotubes structural rearrangement as a template for nanotube growth. It is found that eco-TiO2 can be activated under visible-light irradiation by non-metal (sulfur; S) doping, after which it shows visible-light photocatalytic activities over a range of solar energy. Importantly, an in vitro cytotoxicity test of well-purified water by eco-TiO2 confirms that eco-TiO2 satisfies the key human safety conditions. PMID:25338845

  17. Innovative three-dimensional (3D) eco-TiO2 photocatalysts for practical environmental and bio-medical applications

    NASA Astrophysics Data System (ADS)

    Lee, Hyun Uk; Lee, Soon Chang; Lee, Young-Chul; Son, Byoungchul; Park, So Young; Lee, Jae Won; Oh, You-Kwan; Kim, Yooseok; Choi, Saehae; Lee, Young-Seak; Lee, Jouhahn

    2014-10-01

    It is known that water purified by conventional TiO2 photocatalysts may not be safe enough for drinking, due to the toxicity by tiny existence of TiO2 nanoparticles after water treatment. We herein demonstrate a facile design of a three-dimensional (3D) TiO2 photocatalyst structure with which both the efficiency of purification and the safety level of the final purified water can be improved and ensured, respectively. The structure, consisting of 3D sulfur-doped TiO2 microtubes in nanotubes (eco-TiO2), is suitable for both environmental and bio-medical applications. Investigation of its formation mechanism reveals that anodic aluminum oxide (AAO), owing to a spatial constraint, causes a simple, nanoparticles-to-nanotubes structural rearrangement as a template for nanotube growth. It is found that eco-TiO2 can be activated under visible-light irradiation by non-metal (sulfur; S) doping, after which it shows visible-light photocatalytic activities over a range of solar energy. Importantly, an in vitro cytotoxicity test of well-purified water by eco-TiO2 confirms that eco-TiO2 satisfies the key human safety conditions.

  18. Innovative three-dimensional (3D) eco-TiO₂ photocatalysts for practical environmental and bio-medical applications.

    PubMed

    Lee, Hyun Uk; Lee, Soon Chang; Lee, Young-Chul; Son, Byoungchul; Park, So Young; Lee, Jae Won; Oh, You-Kwan; Kim, Yooseok; Choi, Saehae; Lee, Young-Seak; Lee, Jouhahn

    2014-10-23

    It is known that water purified by conventional TiO2 photocatalysts may not be safe enough for drinking, due to the toxicity by tiny existence of TiO2 nanoparticles after water treatment. We herein demonstrate a facile design of a three-dimensional (3D) TiO2 photocatalyst structure with which both the efficiency of purification and the safety level of the final purified water can be improved and ensured, respectively. The structure, consisting of 3D sulfur-doped TiO2 microtubes in nanotubes (eco-TiO2), is suitable for both environmental and bio-medical applications. Investigation of its formation mechanism reveals that anodic aluminum oxide (AAO), owing to a spatial constraint, causes a simple, nanoparticles-to-nanotubes structural rearrangement as a template for nanotube growth. It is found that eco-TiO2 can be activated under visible-light irradiation by non-metal (sulfur; S) doping, after which it shows visible-light photocatalytic activities over a range of solar energy. Importantly, an in vitro cytotoxicity test of well-purified water by eco-TiO2 confirms that eco-TiO2 satisfies the key human safety conditions.

  19. Fabrication of a three dimensional particle focusing microfluidic device using a 3D printer, PDMS, and glass

    NASA Astrophysics Data System (ADS)

    Collette, Robyn; Rosen, Daniel; Shirk, Kathryn

    Microfluidic devices have high importance in fields such as bioanalysis because they can manipulate volumes of fluid in the range of microliters to picoliters. Small samples can be quickly and easily tested using complex microfluidic devices. Typically, these devices are created through lithography techniques, which can be costly and time consuming. It has been shown that inexpensive microfluidic devices can be produced quickly using a 3D printer and PDMS. However, a size limitation prohibits the fabrication of precisely controlled microchannels. By using shrinking materials in combination with 3D printing of flow-focusing geometries, this limitation can be overcome. This research seeks to employ these techniques to quickly fabricate an inexpensive, working device with three dimensional particle focusing capabilities. By modifying the channel geometry, colloidal particles in a solution will be focused into a single beam when passed through this device. The ability to focus particles is necessary for a variety of biological applications which requires precise detection and characterization of particles in a sample. We would like to thank the Shippensburg University Undergraduate Research Grant Program for their generous funding.

  20. Human platelet lysate improves human cord blood derived ECFC survival and vasculogenesis in three dimensional (3D) collagen matrices.

    PubMed

    Kim, Hyojin; Prasain, Nutan; Vemula, Sasidhar; Ferkowicz, Michael J; Yoshimoto, Momoko; Voytik-Harbin, Sherry L; Yoder, Mervin C

    2015-09-01

    Human cord blood (CB) is enriched in circulating endothelial colony forming cells (ECFCs) that display high proliferative potential and in vivo vessel forming ability. Since diminished ECFC survival is known to dampen the vasculogenic response in vivo, we tested how long implanted ECFC survive and generate vessels in three-dimensional (3D) type I collagen matrices in vitro and in vivo. We hypothesized that human platelet lysate (HPL) would promote cell survival and enhance vasculogenesis in the 3D collagen matrices. We report that the percentage of ECFC co-cultured with HPL that were alive was significantly enhanced on days 1 and 3 post-matrix formation, compared to ECFC alone containing matrices. Also, co-culture of ECFC with HPL displayed significantly more vasculogenic activity compared to ECFC alone and expressed significantly more pro-survival molecules (pAkt, p-Bad and Bcl-xL) in the 3D collagen matrices in vitro. Treatment with Akt1 inhibitor (A-674563), Akt2 inhibitor (CCT128930) and Bcl-xL inhibitor (ABT-263/Navitoclax) significantly decreased the cell survival and vasculogenesis of ECFC co-cultured with or without HPL and implicated activation of the Akt1 pathway as the critical mediator of the HPL effect on ECFC in vitro. A significantly greater average vessel number and total vascular area of human CD31(+) vessels were present in implants containing ECFC and HPL, compared to the ECFC alone implants in vivo. We conclude that implantation of ECFC with HPL in vivo promotes vasculogenesis and augments blood vessel formation via diminishing apoptosis of the implanted ECFC.

  1. Overview of 3D-TRACE, a NASA Initiative in Three-Dimensional Tomography of the Aerosol-Cloud Environment

    NASA Astrophysics Data System (ADS)

    Davis, Anthony; Diner, David; Yanovsky, Igor; Garay, Michael; Xu, Feng; Bal, Guillaume; Schechner, Yoav; Aides, Amit; Qu, Zheng; Emde, Claudia

    2013-04-01

    Remote sensing is a key tool for sorting cloud ensembles by dynamical state, aerosol environments by source region, and establishing causal relationships between aerosol amounts, type, and cloud microphysics-the so-called indirect aerosol climate impacts, and one of the main sources of uncertainty in current climate models. Current satellite imagers use data processing approaches that invariably start with cloud detection/masking to isolate aerosol air-masses from clouds, and then rely on one-dimensional (1D) radiative transfer (RT) to interpret the aerosol and cloud measurements in isolation. Not only does this lead to well-documented biases for the estimates of aerosol radiative forcing and cloud optical depths in current missions, but it is fundamentally inadequate for future missions such as EarthCARE where capturing the complex, three-dimensional (3D) interactions between clouds and aerosols is a primary objective. In order to advance the state of the art, the next generation of satellite information processing systems must incorporate technologies that will enable the treatment of the atmosphere as a fully 3D environment, represented more realistically as a continuum. At one end, there is an optically thin background dominated by aerosols and molecular scattering that is strongly stratified and relatively homogeneous in the horizontal. At the other end, there are optically thick embedded elements, clouds and aerosol plumes, which can be more or less uniform and quasi-planar or else highly 3D with boundaries in all directions; in both cases, strong internal variability may be present. To make this paradigm shift possible, we propose to combine the standard models for satellite signal prediction physically grounded in 1D and 3D RT, both scalar and vector, with technologies adapted from biomedical imaging, digital image processing, and computer vision. This will enable us to demonstrate how the 3D distribution of atmospheric constituents, and their associated

  2. Revisit to three-dimensional percolation theory: Accurate analysis for highly stretchable conductive composite materials

    PubMed Central

    Kim, Sangwoo; Choi, Seongdae; Oh, Eunho; Byun, Junghwan; Kim, Hyunjong; Lee, Byeongmoon; Lee, Seunghwan; Hong, Yongtaek

    2016-01-01

    A percolation theory based on variation of conductive filler fraction has been widely used to explain the behavior of conductive composite materials under both small and large deformation conditions. However, it typically fails in properly analyzing the materials under the large deformation since the assumption may not be valid in such a case. Therefore, we proposed a new three-dimensional percolation theory by considering three key factors: nonlinear elasticity, precisely measured strain-dependent Poisson’s ratio, and strain-dependent percolation threshold. Digital image correlation (DIC) method was used to determine actual Poisson’s ratios at various strain levels, which were used to accurately estimate variation of conductive filler volume fraction under deformation. We also adopted strain-dependent percolation threshold caused by the filler re-location with deformation. When three key factors were considered, electrical performance change was accurately analyzed for composite materials with both isotropic and anisotropic mechanical properties. PMID:27694856

  3. Revisit to three-dimensional percolation theory: Accurate analysis for highly stretchable conductive composite materials

    NASA Astrophysics Data System (ADS)

    Kim, Sangwoo; Choi, Seongdae; Oh, Eunho; Byun, Junghwan; Kim, Hyunjong; Lee, Byeongmoon; Lee, Seunghwan; Hong, Yongtaek

    2016-10-01

    A percolation theory based on variation of conductive filler fraction has been widely used to explain the behavior of conductive composite materials under both small and large deformation conditions. However, it typically fails in properly analyzing the materials under the large deformation since the assumption may not be valid in such a case. Therefore, we proposed a new three-dimensional percolation theory by considering three key factors: nonlinear elasticity, precisely measured strain-dependent Poisson’s ratio, and strain-dependent percolation threshold. Digital image correlation (DIC) method was used to determine actual Poisson’s ratios at various strain levels, which were used to accurately estimate variation of conductive filler volume fraction under deformation. We also adopted strain-dependent percolation threshold caused by the filler re-location with deformation. When three key factors were considered, electrical performance change was accurately analyzed for composite materials with both isotropic and anisotropic mechanical properties.

  4. Accurate three-dimensional virtual reconstruction of surgical field using calibrated trajectories of an image-guided medical robot

    PubMed Central

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

    2014-01-01

    Abstract. Brain tumor margin removal is challenging because diseased tissue is often visually indistinguishable from healthy tissue. Leaving residual tumor leads to decreased survival, and removing normal tissue causes life-long neurological deficits. Thus, a surgical robotics system with a high degree of dexterity, accurate navigation, and highly precise resection is an ideal candidate for image-guided removal of fluorescently labeled brain tumor cells. To image, we developed a scanning fiber endoscope (SFE) which acquires concurrent reflectance and fluorescence wide-field images at a high resolution. This miniature flexible endoscope was affixed to the arm of a RAVEN II surgical robot providing programmable motion with feedback control using stereo-pair surveillance cameras. To verify the accuracy of the three-dimensional (3-D) reconstructed surgical field, a multimodal physical-sized model of debulked brain tumor was used to obtain the 3-D locations of residual tumor for robotic path planning to remove fluorescent cells. Such reconstruction is repeated intraoperatively during margin clean-up so the algorithm efficiency and accuracy are important to the robotically assisted surgery. Experimental results indicate that the time for creating this 3-D surface can be reduced to one-third by using known trajectories of a robot arm, and the error from the reconstructed phantom is within 0.67 mm in average compared to the model design. PMID:26158071

  5. Three-dimensional dynamic contrast-enhanced MRI for the accurate, extensive quantification of microvascular permeability in atherosclerotic plaques.

    PubMed

    Calcagno, Claudia; Lobatto, Mark E; Dyvorne, Hadrien; Robson, Philip M; Millon, Antoine; Senders, Max L; Lairez, Olivier; Ramachandran, Sarayu; Coolen, Bram F; Black, Alexandra; Mulder, Willem J M; Fayad, Zahi A

    2015-10-01

    Atherosclerotic plaques that cause stroke and myocardial infarction are characterized by increased microvascular permeability and inflammation. Dynamic contrast-enhanced MRI (DCE-MRI) has been proposed as a method to quantify vessel wall microvascular permeability in vivo. Until now, most DCE-MRI studies of atherosclerosis have been limited to two-dimensional (2D) multi-slice imaging. Although providing the high spatial resolution required to image the arterial vessel wall, these approaches do not allow the quantification of plaque permeability with extensive anatomical coverage, an essential feature when imaging heterogeneous diseases, such as atherosclerosis. To our knowledge, we present the first systematic evaluation of three-dimensional (3D), high-resolution, DCE-MRI for the extensive quantification of plaque permeability along an entire vascular bed, with validation in atherosclerotic rabbits. We compare two acquisitions: 3D turbo field echo (TFE) with motion-sensitized-driven equilibrium (MSDE) preparation and 3D turbo spin echo (TSE). We find 3D TFE DCE-MRI to be superior to 3D TSE DCE-MRI in terms of temporal stability metrics. Both sequences show good intra- and inter-observer reliability, and significant correlation with ex vivo permeability measurements by Evans Blue near-infrared fluorescence (NIRF). In addition, we explore the feasibility of using compressed sensing to accelerate 3D DCE-MRI of atherosclerosis, to improve its temporal resolution and therefore the accuracy of permeability quantification. Using retrospective under-sampling and reconstructions, we show that compressed sensing alone may allow the acceleration of 3D DCE-MRI by up to four-fold. We anticipate that the development of high-spatial-resolution 3D DCE-MRI with prospective compressed sensing acceleration may allow for the more accurate and extensive quantification of atherosclerotic plaque permeability along an entire vascular bed. We foresee that this approach may allow for

  6. Three dimensional accurate morphology measurements of polystyrene standard particles on silicon substrate by electron tomography.

    PubMed

    Hayashida, Misa; Kumagai, Kazuhiro; Malac, Marek

    2015-12-01

    Polystyrene latex (PSL) nanoparticle (NP) sample is one of the most widely used standard materials. It is used for calibration of particle counters and particle size measurement tools. It has been reported that the measured NP sizes by various methods, such as Differential Mobility Analysis, dynamic light scattering (DLS), optical microscopy (OM), scanning electron microscopy (SEM) and atomic force microscopy (AFM), differ from each other. Deformation of PSL NPs on mica substrate has been reported in AFM measurements: the lateral width of PSL NPs is smaller than their vertical height. To provide a reliable calibration standard, the deformation must be measured by a method that can reliably visualize the entire three dimensional (3D) shape of the PSL NPs. Here we present a method for detailed measurement of PSL NP 3D shape by means of electron tomography in a transmission electron microscope. The observed shape of the PSL NPs with 100 nm and 50 nm diameter were not spherical, but squished in direction perpendicular to the support substrate by about 7.4% and 12.1%, respectively. The high difference in surface energy of the PSL NPs and that of substrate together with their low Young modulus appear to explain the squishing of the NPs without presence of water film.

  7. Three-dimensional ultrashort echo time cones T1ρ (3D UTE-cones-T1ρ ) imaging.

    PubMed

    Ma, Ya-Jun; Carl, Michael; Shao, Hongda; Tadros, Anthony S; Chang, Eric Y; Du, Jiang

    2017-03-20

    We report a novel three-dimensional (3D) ultrashort echo time (UTE) sequence employing Cones trajectory and T1ρ preparation (UTE-Cones-T1ρ ) for quantitative T1ρ assessment of short T2 tissues in the musculoskeletal system. A basic 3D UTE-Cones sequence was combined with a spin-locking preparation pulse for T1ρ contrast. A relatively short TR was used to decrease the scan time, which required T1 measurement and compensation using 3D UTE-Cones data acquisitions with variable TRs. Another strategy to reduce the total scan time was to acquire multiple Cones spokes (Nsp ) after each T1ρ preparation and fat saturation. Four spin-locking times (TSL = 0-20 ms) were acquired over 12 min, plus another 7 min for T1 measurement. The 3D UTE-Cones-T1ρ sequence was compared with a two-dimensional (2D) spiral-T1ρ sequence for the imaging of a spherical CuSO4 phantom and ex vivo meniscus and tendon specimens, as well as the knee and ankle joints of healthy volunteers, using a clinical 3-T scanner. The CuSO4 phantom showed a T1ρ value of 76.5 ± 1.6 ms with the 2D spiral-T1ρ sequence, as well as 85.7 ± 3.6 and 89.2 ± 1.4 ms for the 3D UTE-Cones-T1ρ sequences with Nsp of 1 and 5, respectively. The 3D UTE-Cones-T1ρ sequence provided shorter T1ρ values for the bovine meniscus sample relative to the 2D spiral-T1ρ sequence (10-12 ms versus 16 ms, respectively). The cadaveric human Achilles tendon sample could only be imaged with the 3D UTE-Cones-T1ρ sequence (T1ρ  = 4.0 ± 0.9 ms), with the 2D spiral-T1ρ sequence demonstrating near-zero signal intensity. Human studies yielded T1ρ values of 36.1 ± 2.9, 18.3 ± 3.9 and 3.1 ± 0.4 ms for articular cartilage, meniscus and the Achilles tendon, respectively. The 3D UTE-Cones-T1ρ sequence allows volumetric T1ρ measurement of short T2 tissues in vivo.

  8. Searching for Thermal Anomalies on Icy Satellites: Step 1- Validation of the Three Dimensional Volatile-Transport (VT3D)

    NASA Astrophysics Data System (ADS)

    Simmons, Gary G.; Howett, Carly J. A.; Young, Leslie A.; Spencer, John R.

    2015-11-01

    In the last few decades, thermal data from the Galileo and Cassini spacecraft have detected various anomalies on Jovian and Saturnian satellites, including the thermally anomalous “PacMan” regions on Mimas and Tethys and the Pwyll anomaly on Europa (Howett et al. 2011, Howett et al. 2012, Spencer et al. 1999). Yet, the peculiarities of some of these anomalies, like the weak detection of the “PacMan” anomalies on Rhea and Dione and the low thermal inertia values of the widespread anomalies on equatorial Europa, are subjects for on-going research (Howett et al. 2014, Rathbun et al. 2010). Further, analysis and review of all the data both Galileo and Cassini took of these worlds will provide information of the thermal inertia and albedos of their surfaces, perhaps highlighting potential targets of interest for future Jovian and Saturnian system missions. Many previous works have used a thermophysical model for airless planets developed by Spencer (1990). However, the Three Dimensional Volatile-Transport (VT3D) model proposed by Young (2012) is able to predict surface temperatures in significantly faster computation time, incorporating seasonal and diurnal insolation variations. This work is the first step in an ongoing investigation, which will use VT3D’s capabilities to reanalyze Galileo and Cassini data. VT3D, which has already been used to analyze volatile transport on Pluto, is validated by comparing its results to that of the Spencer thermal model. We will also present our initial results using VT3D to reanalyze the thermophysical properties of the PacMan anomaly previous discovered on Mimas by Howett et al. (2011), using temperature constraints of diurnal data from Cassini/CIRS. VT3D is expected to be an efficient tool in identifying new thermal anomalies in future Saturnian and Jovian missions.Bibliography:C.J.A. Howett et al. (2011), Icarus 216, 221.C.J.A. Howett et al. (2012), Icarus 221, 1084.C.J.A. Howett et al. (2014), Icarus 241, 239.J

  9. Breakup of Finite-Size Colloidal Aggregates in Turbulent Flow Investigated by Three-Dimensional (3D) Particle Tracking Velocimetry.

    PubMed

    Saha, Debashish; Babler, Matthaus U; Holzner, Markus; Soos, Miroslav; Lüthi, Beat; Liberzon, Alex; Kinzelbach, Wolfgang

    2016-01-12

    Aggregates grown in mild shear flow are released, one at a time, into homogeneous isotropic turbulence, where their motion and intermittent breakup is recorded by three-dimensional particle tracking velocimetry (3D-PTV). The aggregates have an open structure with a fractal dimension of ∼2.2, and their size is 1.4 ± 0.4 mm, which is large, compared to the Kolmogorov length scale (η = 0.15 mm). 3D-PTV of flow tracers allows for the simultaneous measurement of aggregate trajectories and the full velocity gradient tensor along their pathlines, which enables us to access the Lagrangian stress history of individual breakup events. From this data, we found no consistent pattern that relates breakup to the local flow properties at the point of breakup. Also, the correlation between the aggregate size and both shear stress and normal stress at the location of breakage is found to be weaker, when compared with the correlation between size and drag stress. The analysis suggests that the aggregates are mostly broken due to the accumulation of the drag stress over a time lag on the order of the Kolmogorov time scale. This finding is explained by the fact that the aggregates are large, which gives their motion inertia and increases the time for stress propagation inside the aggregate. Furthermore, it is found that the scaling of the largest fragment and the accumulated stress at breakup follows an earlier established power law, i.e., dfrag ∼ σ(-0.6) obtained from laminar nozzle experiments. This indicates that, despite the large size and the different type of hydrodynamic stress, the microscopic mechanism causing breakup is consistent over a wide range of aggregate size and stress magnitude.

  10. Estimation of three-dimensional knee joint movement using bi-plane x-ray fluoroscopy and 3D-CT

    NASA Astrophysics Data System (ADS)

    Haneishi, Hideaki; Fujita, Satoshi; Kohno, Takahiro; Suzuki, Masahiko; Miyagi, Jin; Moriya, Hideshige

    2005-04-01

    Acquisition of exact information of three-dimensional knee joint movement is desired in plastic surgery. Conventional X-ray fluoroscopy provides dynamic but just two-dimensional projected image. On the other hand, three-dimensional CT provides three-dimensional but just static image. In this paper, a method for acquiring three-dimensional knee joint movement using both bi-plane, dynamic X-ray fluoroscopy and static three-dimensional CT is proposed. Basic idea is use of 2D/3D registration using digitally reconstructed radiograph (DRR) or virtual projection of CT data. Original ideal is not new but the application of bi-plane fluoroscopy to natural bones of knee is reported for the first time. The technique was applied to two volunteers and successful results were obtained. Accuracy evaluation through computer simulation and phantom experiment with a knee joint of a pig were also conducted.

  11. Experimental Investigation of Three-Dimensional (3-D) Material Flow Pattern in Thick Dissimilar 2050 Friction-Stir Welds

    NASA Astrophysics Data System (ADS)

    Avettand-Fènoël, Marie-Noëlle; Taillard, Roland; Laye, Julien; Odièvre, Thierry

    2014-02-01

    The current microstructural investigation performed at various scales deals with the three-dimensional (3-D) material flow in thick dissimilar Airware™ 2050 friction-stir butt welds (Airware, Newport Beach, CA) because of the scarcity of the results obtained with thicker than 8 mm joints and the lack of detailed interpretation of features in the longitudinal direction. An additional originality consists in the study of material flow under the probe tip. In the current case of thick plates, the variation of local temperature along the weld depth is of key importance for the material flow. Indeed, it governs the slight difference of local mechanical behavior between both materials and therefore the shift of the interface, which was clearly put into evidence by means of a difference of Mn content as small as 0.3 pct between both alloys. This importance of temperature for the malleability also entails the pear shape of the nugget as well as a change of grains orientation along the depth in the thermomechanically affected zone. Due to the modification of tool-material adhesion with temperature, a new phenomenological model of material flow for thick friction-stir welds is proposed. In accordance with their difference of origin, the coexistence of onion rings and serrated interface is also highlighted.

  12. Particle tracking approach for transport in three-dimensional discrete fracture networks: Particle tracking in 3-D DFNs

    SciTech Connect

    Makedonska, Nataliia; Painter, Scott L.; Bui, Quan M.; Gable, Carl W.; Karra, Satish

    2015-09-16

    The discrete fracture network (DFN) model is a method to mimic discrete pathways for fluid flow through a fractured low-permeable rock mass, and may be combined with particle tracking simulations to address solute transport. However, experience has shown that it is challenging to obtain accurate transport results in three-dimensional DFNs because of the high computational burden and difficulty in constructing a high-quality unstructured computational mesh on simulated fractures. We present a new particle tracking capability, which is adapted to control volume (Voronoi polygons) flow solutions on unstructured grids (Delaunay triangulations) on three-dimensional DFNs. The locally mass-conserving finite-volume approach eliminates mass balance-related problems during particle tracking. The scalar fluxes calculated for each control volume face by the flow solver are used to reconstruct a Darcy velocity at each control volume centroid. The groundwater velocities can then be continuously interpolated to any point in the domain of interest. The control volumes at fracture intersections are split into four pieces, and the velocity is reconstructed independently on each piece, which results in multiple groundwater velocities at the intersection, one for each fracture on each side of the intersection line. This technique enables detailed particle transport representation through a complex DFN structure. Verified for small DFNs, the new simulation capability enables numerical experiments on advective transport in large DFNs to be performed. As a result, we demonstrate this particle transport approach on a DFN model using parameters similar to those of crystalline rock at a proposed geologic repository for spent nuclear fuel in Forsmark, Sweden.

  13. Particle tracking approach for transport in three-dimensional discrete fracture networks: Particle tracking in 3-D DFNs

    DOE PAGES

    Makedonska, Nataliia; Painter, Scott L.; Bui, Quan M.; ...

    2015-09-16

    The discrete fracture network (DFN) model is a method to mimic discrete pathways for fluid flow through a fractured low-permeable rock mass, and may be combined with particle tracking simulations to address solute transport. However, experience has shown that it is challenging to obtain accurate transport results in three-dimensional DFNs because of the high computational burden and difficulty in constructing a high-quality unstructured computational mesh on simulated fractures. We present a new particle tracking capability, which is adapted to control volume (Voronoi polygons) flow solutions on unstructured grids (Delaunay triangulations) on three-dimensional DFNs. The locally mass-conserving finite-volume approach eliminates massmore » balance-related problems during particle tracking. The scalar fluxes calculated for each control volume face by the flow solver are used to reconstruct a Darcy velocity at each control volume centroid. The groundwater velocities can then be continuously interpolated to any point in the domain of interest. The control volumes at fracture intersections are split into four pieces, and the velocity is reconstructed independently on each piece, which results in multiple groundwater velocities at the intersection, one for each fracture on each side of the intersection line. This technique enables detailed particle transport representation through a complex DFN structure. Verified for small DFNs, the new simulation capability enables numerical experiments on advective transport in large DFNs to be performed. As a result, we demonstrate this particle transport approach on a DFN model using parameters similar to those of crystalline rock at a proposed geologic repository for spent nuclear fuel in Forsmark, Sweden.« less

  14. A time accurate finite volume high resolution scheme for three dimensional Navier-Stokes equations

    NASA Technical Reports Server (NTRS)

    Liou, Meng-Sing; Hsu, Andrew T.

    1989-01-01

    A time accurate, three-dimensional, finite volume, high resolution scheme for solving the compressible full Navier-Stokes equations is presented. The present derivation is based on the upwind split formulas, specifically with the application of Roe's (1981) flux difference splitting. A high-order accurate (up to the third order) upwind interpolation formula for the inviscid terms is derived to account for nonuniform meshes. For the viscous terms, discretizations consistent with the finite volume concept are described. A variant of second-order time accurate method is proposed that utilizes identical procedures in both the predictor and corrector steps. Avoiding the definition of midpoint gives a consistent and easy procedure, in the framework of finite volume discretization, for treating viscous transport terms in the curvilinear coordinates. For the boundary cells, a new treatment is introduced that not only avoids the use of 'ghost cells' and the associated problems, but also satisfies the tangency conditions exactly and allows easy definition of viscous transport terms at the first interface next to the boundary cells. Numerical tests of steady and unsteady high speed flows show that the present scheme gives accurate solutions.

  15. Thoracic Temporal Subtraction Three Dimensional Computed Tomography (3D-CT): Screening for Vertebral Metastases of Primary Lung Cancers

    PubMed Central

    Iwano, Shingo; Ito, Rintaro; Umakoshi, Hiroyasu; Karino, Takatoshi; Inoue, Tsutomu; Li, Yuanzhong; Naganawa, Shinji

    2017-01-01

    Purpose We developed an original, computer-aided diagnosis (CAD) software that subtracts the initial thoracic vertebral three-dimensional computed tomography (3D-CT) image from the follow-up 3D-CT image. The aim of this study was to investigate the efficacy of this CAD software during screening for vertebral metastases on follow-up CT images of primary lung cancer patients. Materials and Methods The interpretation experiment included 30 sets of follow-up CT scans in primary lung cancer patients and was performed by two readers (readers A and B), who each had 2.5 years’ experience reading CT images. In 395 vertebrae from C6 to L3, 46 vertebral metastases were identified as follows: osteolytic metastases (n = 17), osteoblastic metastases (n = 14), combined osteolytic and osteoblastic metastases (n = 6), and pathological fractures (n = 9). Thirty-six lesions were in the anterior component (vertebral body), and 10 lesions were in the posterior component (vertebral arch, transverse process, and spinous process). The area under the curve (AUC) by receiver operating characteristic (ROC) curve analysis and the sensitivity and specificity for detecting vertebral metastases were compared with and without CAD for each observer. Results Reader A detected 47 abnormalities on CT images without CAD, and 33 of them were true-positive metastatic lesions. Using CAD, reader A detected 57 abnormalities, and 38 were true positives. The sensitivity increased from 0.717 to 0.826, and on ROC curve analysis, AUC with CAD was significantly higher than that without CAD (0.849 vs. 0.902, p = 0.021). Reader B detected 40 abnormalities on CT images without CAD, and 36 of them were true-positive metastatic lesions. Using CAD, reader B detected 44 abnormalities, and 39 were true positives. The sensitivity increased from 0.783 to 0.848, and AUC with CAD was nonsignificantly higher than that without CAD (0.889 vs. 0.910, p = 0.341). Both readers detected more osteolytic and osteoblastic

  16. Calculation of three-dimensional (3-D) internal flow by means of the velocity-vorticity formulation on a staggered grid

    NASA Technical Reports Server (NTRS)

    Stremel, Paul M.

    1995-01-01

    A method has been developed to accurately compute the viscous flow in three-dimensional (3-D) enclosures. This method is the 3-D extension of a two-dimensional (2-D) method developed for the calculation of flow over airfoils. The 2-D method has been tested extensively and has been shown to accurately reproduce experimental results. As in the 2-D method, the 3-D method provides for the non-iterative solution of the incompressible Navier-Stokes equations by means of a fully coupled implicit technique. The solution is calculated on a body fitted computational mesh incorporating a staggered grid methodology. In the staggered grid method, the three components of vorticity are defined at the centers of the computational cell sides, while the velocity components are defined as normal vectors at the centers of the computational cell faces. The staggered grid orientation provides for the accurate definition of the vorticity components at the vorticity locations, the divergence of vorticity at the mesh cell nodes and the conservation of mass at the mesh cell centers. The solution is obtained by utilizing a fractional step solution technique in the three coordinate directions. The boundary conditions for the vorticity and velocity are calculated implicitly as part of the solution. The method provides for the non-iterative solution of the flow field and satisfies the conservation of mass and divergence of vorticity to machine zero at each time step. To test the method, the calculation of simple driven cavity flows have been computed. The driven cavity flow is defined as the flow in an enclosure driven by a moving upper plate at the top of the enclosure. To demonstrate the ability of the method to predict the flow in arbitrary cavities, results will he shown for both cubic and curved cavities.

  17. Three-dimensional accurate detection of lung emphysema in rats using ultra-short and zero echo time MRI.

    PubMed

    Bianchi, Andrea; Tibiletti, Marta; Kjørstad, Åsmund; Birk, Gerald; Schad, Lothar R; Stierstorfer, Birgit; Rasche, Volker; Stiller, Detlef

    2015-11-01

    Emphysema is a life-threatening pathology that causes irreversible destruction of alveolar walls. In vivo imaging techniques play a fundamental role in the early non-invasive pre-clinical and clinical detection and longitudinal follow-up of this pathology. In the present study, we aimed to evaluate the feasibility of using high resolution radial three-dimensional (3D) zero echo time (ZTE) and 3D ultra-short echo time (UTE) MRI to accurately detect lung pathomorphological changes in a rodent model of emphysema.Porcine pancreas elastase (PPE) was intratracheally administered to the rats to produce the emphysematous changes. 3D ZTE MRI, low and high definition 3D UTE MRI and micro-computed tomography images were acquired 4 weeks after the PPE challenge. Signal-to-noise ratios (SNRs) were measured in PPE-treated and control rats. T2* values were computed from low definition 3D UTE MRI. Histomorphometric measurements were made after euthanizing the animals. Both ZTE and UTE MR images showed a significant decrease in the SNR measured in PPE-treated lungs compared with controls, due to the pathomorphological changes taking place in the challenged lungs. A significant decrease in T2* values in PPE-challenged animals compared with controls was measured using UTE MRI. Histomorphometric measurements showed a significant increase in the mean linear intercept in PPE-treated lungs. UTE yielded significantly higher SNR compared with ZTE (14% and 30% higher in PPE-treated and non-PPE-treated lungs, respectively).This study showed that optimized 3D radial UTE and ZTE MRI can provide lung images of excellent quality, with high isotropic spatial resolution (400 µm) and SNR in parenchymal tissue (>25) and negligible motion artifacts in freely breathing animals. These techniques were shown to be useful non-invasive instruments to accurately and reliably detect the pathomorphological alterations taking place in emphysematous lungs, without incurring the risks of cumulative radiation

  18. Technical Note: PRESAGE three-dimensional dosimetry accurately measures Gamma Knife output factors

    PubMed Central

    Klawikowski, Slade J.; Yang, James N.; Adamovics, John; Ibbott, Geoffrey S.

    2014-01-01

    Small-field output factor measurements are traditionally very difficult because of steep dose gradients, loss of lateral electronic equilibrium, and dose volume averaging in finitely sized detectors. Three-dimensional (3D) dosimetry is ideal for measuring small output factors and avoids many of these potential challenges of point and two-dimensional detectors. PRESAGE 3D polymer dosimeters were used to measure the output factors for the 4 mm and 8 mm collimators of the Leksell Perfexion Gamma Knife radiosurgery treatment system. Discrepancies between the planned and measured distance between shot centers were also investigated. A Gamma Knife head frame was mounted onto an anthropomorphic head phantom. Special inserts were machined to hold 60 mm diameter, 70 mm tall cylindrical PRESAGE dosimeters. The phantom was irradiated with one 16 mm shot and either one 4 mm or one 8 mm shot, to a prescribed dose of either 3 Gy or 4 Gy to the 50% isodose line. The two shots were spaced between 30 mm and 60 mm apart and aligned along the central axis of the cylinder. The Presage dosimeters were measured using the DMOS-RPC optical CT scanning system. Five independent 4 mm output factor measurements fell within 2% of the manufacturer’s Monte Carlo simulation-derived nominal value, as did two independent 8 mm output factor measurements. The measured distances between shot centers varied by ± 0.8 mm with respect to the planned shot displacements. On the basis of these results, we conclude that PRESAGE dosimetry is excellently suited to quantify the difficult-to-measure Gamma Knife output factors. PMID:25368961

  19. Fiddler crabs accurately measure two-dimensional distance over three-dimensional terrain.

    PubMed

    Walls, Michael L; Layne, John E

    2009-10-01

    Foraging fiddler crabs (Uca spp.) monitor the location of, and are able to return to, their burrows by employing path integration. This requires them to accurately measure both the directions and distances of their locomotory movements. Even though most fiddler crabs inhabit relatively flat terrain, they must cope with vertical features of their environment, such as sloping beaches, mounds and shells, which may represent significant obstacles. To determine whether fiddler crabs can successfully perform path integration among such three-dimensional obstacles, we tested their ability to measure distance while we imposed a vertical detour. By inserting a large hill in the homeward path of foraging crabs we show that fiddler crabs can cope with vertical detours: they accurately travel the correct horizontal distance, despite the fact that the shape of the hill forces them to change their gait from what would be used on flat ground. Our results demonstrate a flexible path integrator capable of measuring, and either integrating or discarding, the vertical dimension.

  20. Investigation Of Integrating Three-Dimensional (3-D) Geometry Into The Visual Anatomical Injury Descriptor (Visual AID) Using WebGL

    DTIC Science & Technology

    2011-08-01

    into the Visual Anatomical Injury Descriptor (Visual AID) Using WebGL AUTUMN KULAGA MENTOR: PATRICK GILLICH WARFIGHTER SURVIVABILITY BRANCH...Investigation Of Integrating Three-Dimensional (3-D) Geometry Into The Visual Anatomical Injury Descriptor (Visual AID) Using WebGL 5a. CONTRACT...discusses the Web-based 3-D environment prototype being developed to understand the feasibility of integrating WebGL into Visual AID. Using WebGL will

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

    ERIC Educational Resources Information Center

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

    2015-01-01

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

  2. A multiblock/multizone code (PAB 3D-v2) for the three-dimensional Navier-Stokes equations: Preliminary applications

    NASA Technical Reports Server (NTRS)

    Abdol-Hamid, Khaled S.

    1990-01-01

    The development and applications of multiblock/multizone and adaptive grid methodologies for solving the three-dimensional simplified Navier-Stokes equations are described. Adaptive grid and multiblock/multizone approaches are introduced and applied to external and internal flow problems. These new implementations increase the capabilities and flexibility of the PAB3D code in solving flow problems associated with complex geometry.

  3. Comparison of Three-Dimensional (3D) Conformal Proton Radiotherapy (RT), 3D Conformal Photon RT, and Intensity-Modulated RT for Retroperitoneal and Intra-Abdominal Sarcomas

    SciTech Connect

    Swanson, Erika L.; Indelicato, Daniel J.; Louis, Debbie; Flampouri, Stella; Li, Zuofeng; Morris, Christopher G.; Paryani, Nitesh; Slopsema, Roelf

    2012-08-01

    Purpose: To compare three-dimensional conformal proton radiotherapy (3DCPT), intensity-modulated photon radiotherapy (IMRT), and 3D conformal photon radiotherapy (3DCRT) to predict the optimal RT technique for retroperitoneal sarcomas. Methods and Materials: 3DCRT, IMRT, and 3DCPT plans were created for treating eight patients with retroperitoneal or intra-abdominal sarcomas. The clinical target volume (CTV) included the gross tumor plus a 2-cm margin, limited by bone and intact fascial planes. For photon plans, the planning target volume (PTV) included a uniform expansion of 5 mm. For the proton plans, the PTV was nonuniform and beam-specific. The prescription dose was 50.4 Gy/Cobalt gray equivalent CGE. Plans were normalized so that >95% of the CTV received 100% of the dose. Results: The CTV was covered adequately by all techniques. The median conformity index was 0.69 for 3DCPT, 0.75 for IMRT, and 0.51 for 3DCRT. The median inhomogeneity coefficient was 0.062 for 3DCPT, 0.066 for IMRT, and 0.073 for 3DCRT. The bowel median volume receiving 15 Gy (V15) was 16.4% for 3DCPT, 52.2% for IMRT, and 66.1% for 3DCRT. The bowel median V45 was 6.3% for 3DCPT, 4.7% for IMRT, and 15.6% for 3DCRT. The median ipsilateral mean kidney dose was 22.5 CGE for 3DCPT, 34.1 Gy for IMRT, and 37.8 Gy for 3DCRT. The median contralateral mean kidney dose was 0 CGE for 3DCPT, 6.4 Gy for IMRT, and 11 Gy for 3DCRT. The median contralateral kidney V5 was 0% for 3DCPT, 49.9% for IMRT, and 99.7% for 3DCRT. Regardless of technique, the median mean liver dose was <30 Gy, and the median cord V50 was 0%. The median integral dose was 126 J for 3DCPT, 400 J for IMRT, and 432 J for 3DCRT. Conclusions: IMRT and 3DCPT result in plans that are more conformal and homogenous than 3DCRT. Based on Quantitative Analysis of Normal Tissue Effects in Clinic benchmarks, the dosimetric advantage of proton therapy may be less gastrointestinal and genitourinary toxicity.

  4. Improving light propagation Monte Carlo simulations with accurate 3D modeling of skin tissue

    SciTech Connect

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

    2008-01-01

    In this paper, we present a 3D light propagation model to simulate multispectral reflectance images of large skin surface areas. In particular, we aim to simulate more accurately the effects of various physiological properties of the skin in the case of subcutaneous vein imaging compared to existing models. Our method combines a Monte Carlo light propagation model, a realistic three-dimensional model of the skin using parametric surfaces and a vision system for data acquisition. We describe our model in detail, present results from the Monte Carlo modeling and compare our results with those obtained with a well established Monte Carlo model and with real skin reflectance images.

  5. A Cavity Corrected 3D-RISM Functional for Accurate Solvation Free Energies

    PubMed Central

    2014-01-01

    We show that an Ng bridge function modified version of the three-dimensional reference interaction site model (3D-RISM-NgB) solvation free energy method can accurately predict the hydration free energy (HFE) of a set of 504 organic molecules. To achieve this, a single unique constant parameter was adjusted to the computed HFE of single atom Lennard-Jones solutes. It is shown that 3D-RISM is relatively accurate at predicting the electrostatic component of the HFE without correction but requires a modification of the nonpolar contribution that originates in the formation of the cavity created by the solute in water. We use a free energy functional with the Ng scaling of the direct correlation function [Ng, K. C. J. Chem. Phys.1974, 61, 2680]. This produces a rapid, reliable small molecule HFE calculation for applications in drug design. PMID:24634616

  6. Nanoelectronic three-dimensional (3D) nanotip sensing array for real-time, sensitive, label-free sequence specific detection of nucleic acids.

    PubMed

    Esfandyarpour, Rahim; Yang, Lu; Koochak, Zahra; Harris, James S; Davis, Ronald W

    2016-02-01

    The improvements in our ability to sequence and genotype DNA have opened up numerous avenues in the understanding of human biology and medicine with various applications, especially in medical diagnostics. But the realization of a label free, real time, high-throughput and low cost biosensing platforms to detect molecular interactions with a high level of sensitivity has been yet stunted due to two factors: one, slow binding kinetics caused by the lack of probe molecules on the sensors and two, limited mass transport due to the planar structure (two-dimensional) of the current biosensors. Here we present a novel three-dimensional (3D), highly sensitive, real-time, inexpensive and label-free nanotip array as a rapid and direct platform to sequence-specific DNA screening. Our nanotip sensors are designed to have a nano sized thin film as their sensing area (~ 20 nm), sandwiched between two sensing electrodes. The tip is then conjugated to a DNA oligonucleotide complementary to the sequence of interest, which is electrochemically detected in real-time via impedance changes upon the formation of a double-stranded helix at the sensor interface. This 3D configuration is specifically designed to improve the biomolecular hit rate and the detection speed. We demonstrate that our nanotip array effectively detects oligonucleotides in a sequence-specific and highly sensitive manner, yielding concentration-dependent impedance change measurements with a target concentration as low as 10 pM and discrimination against even a single mismatch. Notably, our nanotip sensors achieve this accurate, sensitive detection without relying on signal indicators or enhancing molecules like fluorophores. It can also easily be scaled for highly multiplxed detection with up to 5000 sensors/square centimeter, and integrated into microfluidic devices. The versatile, rapid, and sensitive performance of the nanotip array makes it an excellent candidate for point-of-care diagnostics, and high

  7. User’s guide and reference to Ash3d: a three-dimensional model for Eulerian atmospheric tephra transport and deposition

    USGS Publications Warehouse

    Mastin, Larry G.; Randall, Michael J.; Schwaiger, Hans F.; Denlinger, Roger P.

    2013-01-01

    Ash3d is a three-dimensional Eulerian atmospheric model for tephra transport, dispersal, and deposition, written by the authors to study and forecast hazards of volcanic ash clouds and tephra fall. In this report, we explain how to set up simulations using both a web interface and an ASCII input file, and how to view and interpret model output. We also summarize the architecture of the model and some of its properties.

  8. PRESAGE 3D dosimetry accurately measures Gamma Knife output factors

    NASA Astrophysics Data System (ADS)

    Klawikowski, Slade J.; Yang, James N.; Adamovics, John; Ibbott, Geoffrey S.

    2014-12-01

    Small-field output factor measurements are traditionally very difficult because of steep dose gradients, loss of lateral electronic equilibrium, and dose volume averaging in finitely sized detectors. Three-dimensional (3D) dosimetry is ideal for measuring small output factors and avoids many of these potential challenges of point and 2D detectors. PRESAGE 3D polymer dosimeters were used to measure the output factors for the 4 mm and 8 mm collimators of the Leksell Perfexion Gamma Knife radiosurgery treatment system. Discrepancies between the planned and measured distance between shot centers were also investigated. A Gamma Knife head frame was mounted onto an anthropomorphic head phantom. Special inserts were machined to hold 60 mm diameter, 70 mm tall cylindrical PRESAGE dosimeters. The phantom was irradiated with one 16 mm shot and either one 4 mm or one 8 mm shot, to a prescribed dose of either 3 Gy or 4 Gy to the 50% isodose line. The two shots were spaced between 30 mm and 60 mm apart and aligned along the central axis of the cylinder. The Presage dosimeters were measured using the DMOS-RPC optical CT scanning system. Five independent 4 mm output factor measurements fell within 2% of the manufacturer’s Monte Carlo simulation-derived nominal value, as did two independent 8 mm output factor measurements. The measured distances between shot centers varied by ±0.8 mm with respect to the planned shot displacements. On the basis of these results, we conclude that PRESAGE dosimetry is excellently suited to quantify the difficult-to-measure Gamma Knife output factors.

  9. The Rho family GEF Asef2 regulates cell migration in three dimensional (3D) collagen matrices through myosin II.

    PubMed

    Jean, Léolène; Yang, Lijie; Majumdar, Devi; Gao, Yandong; Shi, Mingjian; Brewer, Bryson M; Li, Deyu; Webb, Donna J

    2014-01-01

    Cell migration is fundamental to a variety of physiological processes, including tissue development, homeostasis, and regeneration. Migration has been extensively studied with cells on 2-dimensional (2D) substrates, but much less is known about cell migration in 3D environments. Tissues and organs are 3D, which is the native environment of cells in vivo, pointing to a need to understand migration and the mechanisms that regulate it in 3D environments. To investigate cell migration in 3D environments, we developed microfluidic devices that afford a controlled, reproducible platform for generating 3D matrices. Using these devices, we show that the Rho family guanine nucleotide exchange factor (GEF) Asef2 inhibits cell migration in 3D type I collagen (collagen I) matrices. Treatment of cells with the myosin II (MyoII) inhibitor blebbistatin abolished the decrease in migration by Asef2. Moreover, Asef2 enhanced MyoII activity as shown by increased phosphorylation of serine 19 (S19). Furthermore, Asef2 increased activation of Rac, which is a Rho family small GTPase, in 3D collagen I matrices. Inhibition of Rac activity by treatment with the Rac-specific inhibitor NSC23766 abrogated the Asef2-promoted increase in S19 MyoII phosphorylation. Thus, our results indicate that Asef2 regulates cell migration in 3D collagen I matrices through a Rac-MyoII-dependent mechanism.

  10. Accurate modeling and reconstruction of three-dimensional percolating filamentary microstructures from two-dimensional micrographs via dilation-erosion method

    SciTech Connect

    Guo, En-Yu; Chawla, Nikhilesh; Jing, Tao; Torquato, Salvatore; Jiao, Yang

    2014-03-01

    Heterogeneous materials are ubiquitous in nature and synthetic situations and have a wide range of important engineering applications. Accurate modeling and reconstructing three-dimensional (3D) microstructure of topologically complex materials from limited morphological information such as a two-dimensional (2D) micrograph is crucial to the assessment and prediction of effective material properties and performance under extreme conditions. Here, we extend a recently developed dilation–erosion method and employ the Yeong–Torquato stochastic reconstruction procedure to model and generate 3D austenitic–ferritic cast duplex stainless steel microstructure containing percolating filamentary ferrite phase from 2D optical micrographs of the material sample. Specifically, the ferrite phase is dilated to produce a modified target 2D microstructure and the resulting 3D reconstruction is eroded to recover the percolating ferrite filaments. The dilation–erosion reconstruction is compared with the actual 3D microstructure, obtained from serial sectioning (polishing), as well as the standard stochastic reconstructions incorporating topological connectedness information. The fact that the former can achieve the same level of accuracy as the latter suggests that the dilation–erosion procedure is tantamount to incorporating appreciably more topological and geometrical information into the reconstruction while being much more computationally efficient. - Highlights: • Spatial correlation functions used to characterize filamentary ferrite phase • Clustering information assessed from 3D experimental structure via serial sectioning • Stochastic reconstruction used to generate 3D virtual structure 2D micrograph • Dilation–erosion method to improve accuracy of 3D reconstruction.

  11. Three-dimensional simulation and auto-stereoscopic 3D display of the battlefield environment based on the particle system algorithm

    NASA Astrophysics Data System (ADS)

    Ning, Jiwei; Sang, Xinzhu; Xing, Shujun; Cui, Huilong; Yan, Binbin; Yu, Chongxiu; Dou, Wenhua; Xiao, Liquan

    2016-10-01

    The army's combat training is very important now, and the simulation of the real battlefield environment is of great significance. Two-dimensional information has been unable to meet the demand at present. With the development of virtual reality technology, three-dimensional (3D) simulation of the battlefield environment is possible. In the simulation of 3D battlefield environment, in addition to the terrain, combat personnel and the combat tool ,the simulation of explosions, fire, smoke and other effects is also very important, since these effects can enhance senses of realism and immersion of the 3D scene. However, these special effects are irregular objects, which make it difficult to simulate with the general geometry. Therefore, the simulation of irregular objects is always a hot and difficult research topic in computer graphics. Here, the particle system algorithm is used for simulating irregular objects. We design the simulation of the explosion, fire, smoke based on the particle system and applied it to the battlefield 3D scene. Besides, the battlefield 3D scene simulation with the glasses-free 3D display is carried out with an algorithm based on GPU 4K super-multiview 3D video real-time transformation method. At the same time, with the human-computer interaction function, we ultimately realized glasses-free 3D display of the simulated more realistic and immersed 3D battlefield environment.

  12. NIKE3D: an implicit, finite-deformation, finite element code for analyzing the static and dynamic response of three-dimensional solids

    SciTech Connect

    Hallquist, J.O.

    1981-01-01

    A user's manual is provided for NIKE3D, a fully implicit three-dimensional finite element code for analyzing the large deformation static and dynamic response of inelastic solids. A contact-impact algorithm permits gaps and sliding along material interfaces. By a specialization of this algorithm, such interfaces can be rigidly tied to admit variable zoning without the need of transition regions. Spatial discretization is achieved by the use of 8-node constant pressure solid elements. Bandwidth minimization is optional. Post-processors for NIKE3D include GRAPE for plotting deformed shapes and stress contours and DYNAP for plotting time histories.

  13. GRID3D-v2: An updated version of the GRID2D/3D computer program for generating grid systems in complex-shaped three-dimensional spatial domains

    NASA Technical Reports Server (NTRS)

    Steinthorsson, E.; Shih, T. I-P.; Roelke, R. J.

    1991-01-01

    In order to generate good quality systems for complicated three-dimensional spatial domains, the grid-generation method used must be able to exert rather precise controls over grid-point distributions. Several techniques are presented that enhance control of grid-point distribution for a class of algebraic grid-generation methods known as the two-, four-, and six-boundary methods. These techniques include variable stretching functions from bilinear interpolation, interpolating functions based on tension splines, and normalized K-factors. The techniques developed in this study were incorporated into a new version of GRID3D called GRID3D-v2. The usefulness of GRID3D-v2 was demonstrated by using it to generate a three-dimensional grid system in the coolent passage of a radial turbine blade with serpentine channels and pin fins.

  14. Accurate 3D quantification of the bronchial parameters in MDCT

    NASA Astrophysics Data System (ADS)

    Saragaglia, A.; Fetita, C.; Preteux, F.; Brillet, P. Y.; Grenier, P. A.

    2005-08-01

    The assessment of bronchial reactivity and wall remodeling in asthma plays a crucial role in better understanding such a disease and evaluating therapeutic responses. Today, multi-detector computed tomography (MDCT) makes it possible to perform an accurate estimation of bronchial parameters (lumen and wall areas) by allowing a quantitative analysis in a cross-section plane orthogonal to the bronchus axis. This paper provides the tools for such an analysis by developing a 3D investigation method which relies on 3D reconstruction of bronchial lumen and central axis computation. Cross-section images at bronchial locations interactively selected along the central axis are generated at appropriate spatial resolution. An automated approach is then developed for accurately segmenting the inner and outer bronchi contours on the cross-section images. It combines mathematical morphology operators, such as "connection cost", and energy-controlled propagation in order to overcome the difficulties raised by vessel adjacencies and wall irregularities. The segmentation accuracy was validated with respect to a 3D mathematically-modeled phantom of a pair bronchus-vessel which mimics the characteristics of real data in terms of gray-level distribution, caliber and orientation. When applying the developed quantification approach to such a model with calibers ranging from 3 to 10 mm diameter, the lumen area relative errors varied from 3.7% to 0.15%, while the bronchus area was estimated with a relative error less than 5.1%.

  15. Three dimensional level set based semiautomatic segmentation of atherosclerotic carotid artery wall volume using 3D ultrasound imaging

    NASA Astrophysics Data System (ADS)

    Hossain, Md. Murad; AlMuhanna, Khalid; Zhao, Limin; Lal, Brajesh K.; Sikdar, Siddhartha

    2014-03-01

    3D segmentation of carotid plaque from ultrasound (US) images is challenging due to image artifacts and poor boundary definition. Semiautomatic segmentation algorithms for calculating vessel wall volume (VWV) have been proposed for the common carotid artery (CCA) but they have not been applied on plaques in the internal carotid artery (ICA). In this work, we describe a 3D segmentation algorithm that is robust to shadowing and missing boundaries. Our algorithm uses distance regularized level set method with edge and region based energy to segment the adventitial wall boundary (AWB) and lumen-intima boundary (LIB) of plaques in the CCA, ICA and external carotid artery (ECA). The algorithm is initialized by manually placing points on the boundary of a subset of transverse slices with an interslice distance of 4mm. We propose a novel user defined stopping surface based energy to prevent leaking of evolving surface across poorly defined boundaries. Validation was performed against manual segmentation using 3D US volumes acquired from five asymptomatic patients with carotid stenosis using a linear 4D probe. A pseudo gold-standard boundary was formed from manual segmentation by three observers. The Dice similarity coefficient (DSC), Hausdor distance (HD) and modified HD (MHD) were used to compare the algorithm results against the pseudo gold-standard on 1205 cross sectional slices of 5 3D US image sets. The algorithm showed good agreement with the pseudo gold standard boundary with mean DSC of 93.3% (AWB) and 89.82% (LIB); mean MHD of 0.34 mm (AWB) and 0.24 mm (LIB); mean HD of 1.27 mm (AWB) and 0.72 mm (LIB). The proposed 3D semiautomatic segmentation is the first step towards full characterization of 3D plaque progression and longitudinal monitoring.

  16. Accurate Automatic Detection of Densely Distributed Cell Nuclei in 3D Space

    PubMed Central

    Tokunaga, Terumasa; Kanamori, Manami; Teramoto, Takayuki; Jang, Moon Sun; Kuge, Sayuri; Ishihara, Takeshi; Yoshida, Ryo; Iino, Yuichi

    2016-01-01

    To measure the activity of neurons using whole-brain activity imaging, precise detection of each neuron or its nucleus is required. In the head region of the nematode C. elegans, the neuronal cell bodies are distributed densely in three-dimensional (3D) space. However, no existing computational methods of image analysis can separate them with sufficient accuracy. Here we propose a highly accurate segmentation method based on the curvatures of the iso-intensity surfaces. To obtain accurate positions of nuclei, we also developed a new procedure for least squares fitting with a Gaussian mixture model. Combining these methods enables accurate detection of densely distributed cell nuclei in a 3D space. The proposed method was implemented as a graphical user interface program that allows visualization and correction of the results of automatic detection. Additionally, the proposed method was applied to time-lapse 3D calcium imaging data, and most of the nuclei in the images were successfully tracked and measured. PMID:27271939

  17. Extremely accurate sequential verification of RELAP5-3D

    SciTech Connect

    Mesina, George L.; Aumiller, David L.; Buschman, Francis X.

    2015-11-19

    Large computer programs like RELAP5-3D solve complex systems of governing, closure and special process equations to model the underlying physics of nuclear power plants. Further, these programs incorporate many other features for physics, input, output, data management, user-interaction, and post-processing. For software quality assurance, the code must be verified and validated before being released to users. For RELAP5-3D, verification and validation are restricted to nuclear power plant applications. Verification means ensuring that the program is built right by checking that it meets its design specifications, comparing coding to algorithms and equations and comparing calculations against analytical solutions and method of manufactured solutions. Sequential verification performs these comparisons initially, but thereafter only compares code calculations between consecutive code versions to demonstrate that no unintended changes have been introduced. Recently, an automated, highly accurate sequential verification method has been developed for RELAP5-3D. The method also provides to test that no unintended consequences result from code development in the following code capabilities: repeating a timestep advancement, continuing a run from a restart file, multiple cases in a single code execution, and modes of coupled/uncoupled operation. In conclusion, mathematical analyses of the adequacy of the checks used in the comparisons are provided.

  18. Extremely accurate sequential verification of RELAP5-3D

    DOE PAGES

    Mesina, George L.; Aumiller, David L.; Buschman, Francis X.

    2015-11-19

    Large computer programs like RELAP5-3D solve complex systems of governing, closure and special process equations to model the underlying physics of nuclear power plants. Further, these programs incorporate many other features for physics, input, output, data management, user-interaction, and post-processing. For software quality assurance, the code must be verified and validated before being released to users. For RELAP5-3D, verification and validation are restricted to nuclear power plant applications. Verification means ensuring that the program is built right by checking that it meets its design specifications, comparing coding to algorithms and equations and comparing calculations against analytical solutions and method ofmore » manufactured solutions. Sequential verification performs these comparisons initially, but thereafter only compares code calculations between consecutive code versions to demonstrate that no unintended changes have been introduced. Recently, an automated, highly accurate sequential verification method has been developed for RELAP5-3D. The method also provides to test that no unintended consequences result from code development in the following code capabilities: repeating a timestep advancement, continuing a run from a restart file, multiple cases in a single code execution, and modes of coupled/uncoupled operation. In conclusion, mathematical analyses of the adequacy of the checks used in the comparisons are provided.« less

  19. iRegNet3D: three-dimensional integrated regulatory network for the genomic analysis of coding and non-coding disease mutations.

    PubMed

    Liang, Siqi; Tippens, Nathaniel D; Zhou, Yaoda; Mort, Matthew; Stenson, Peter D; Cooper, David N; Yu, Haiyuan

    2017-01-18

    The mechanistic details of most disease-causing mutations remain poorly explored within the context of regulatory networks. We present a high-resolution three-dimensional integrated regulatory network (iRegNet3D) in the form of a web tool, where we resolve the interfaces of all known transcription factor (TF)-TF, TF-DNA and chromatin-chromatin interactions for the analysis of both coding and non-coding disease-associated mutations to obtain mechanistic insights into their functional impact. Using iRegNet3D, we find that disease-associated mutations may perturb the regulatory network through diverse mechanisms including chromatin looping. iRegNet3D promises to be an indispensable tool in large-scale sequencing and disease association studies.

  20. Micro3D: computer program for three-dimensional reconstruction visualization, and analysis of neuronal populations and barin regions.

    PubMed

    Bjaalie, Jan G; Leergaard, Trygve B; Pettersen, Christian

    2006-04-01

    This article presents a computer program, Micro3D, designed for 3-D reconstruction, visualization, and analysis of coordinate-data (points and lines) recorded from serial sections. The software has primarily been used for studying shapes and dimension of brain regions (contour line data) and distributions of cellular elements such as neuronal cell bodies or axonal terminal fields labeled with tract-tracing techniques (point data). The tissue elements recorded could equally well be labeled with use of other techniques, the only requirement being that the data collected are saved as x,y,z coordinates. Data are typically imported from image-combining computerized microscopy systems or image analysis systems, such as Neurolucida (MicroBrightField, Colchester, VT) or analySIS (Soft Imaging System, Gmbh, Münster, Germany). System requirements are a PC running LINUX. Reconstructions in Micro3D may be rotated and zoomed in real-time, and submitted to perspective viewing and stereo-imaging. Surfaces are re-synthesized on the basis of stacks of contour lines. Clipping is used for defining section-independent subdivisions of the reconstruction. Flattening of curved sheets of points layers (e.g., neurons in a layer) facilitates inspection of complicated distribution patterns. Micro3D computes color-coded density maps. Opportunities for translation of data from different reconstructions into common coordinate systems are also provided. This article demonstrates the use of Micro3D for visualization of complex neuronal distribution patterns in somatosensory and auditory systems. The software is available for download on conditions posted at the NeSys home pages (http://www.nesys.uio.no/) and at The Rodent Brain Workbench (http://www.rbwb.org/).

  1. Towards Accurate Prediction of Turbulent, Three-Dimensional, Recirculating Flows with the NCC

    NASA Technical Reports Server (NTRS)

    Iannetti, A.; Tacina, R.; Jeng, S.-M.; Cai, J.

    2001-01-01

    The National Combustion Code (NCC) was used to calculate the steady state, nonreacting flow field of a prototype Lean Direct Injection (LDI) swirler. This configuration used nine groups of eight holes drilled at a thirty-five degree angle to induce swirl. These nine groups created swirl in the same direction, or a corotating pattern. The static pressure drop across the holes was fixed at approximately four percent. Computations were performed on one quarter of the geometry, because the geometry is considered rotationally periodic every ninety degrees. The final computational grid used was approximately 2.26 million tetrahedral cells, and a cubic nonlinear k - epsilon model was used to model turbulence. The NCC results were then compared to time averaged Laser Doppler Velocimetry (LDV) data. The LDV measurements were performed on the full geometry, but four ninths of the geometry was measured. One-, two-, and three-dimensional representations of both flow fields are presented. The NCC computations compare both qualitatively and quantitatively well to the LDV data, but differences exist downstream. The comparison is encouraging, and shows that NCC can be used for future injector design studies. To improve the flow prediction accuracy of turbulent, three-dimensional, recirculating flow fields with the NCC, recommendations are given.

  2. FEMFLOW3D; a finite-element program for the simulation of three-dimensional aquifers; version 1.0

    USGS Publications Warehouse

    Durbin, Timothy J.; Bond, Linda D.

    1998-01-01

    This document also includes model validation, source code, and example input and output files. Model validation was performed using four test problems. For each test problem, the results of a model simulation with FEMFLOW3D were compared with either an analytic solution or the results of an independent numerical approach. The source code, written in the ANSI x3.9-1978 FORTRAN standard, and the complete input and output of an example problem are listed in the appendixes.

  3. Three-Dimensional Ballistocardiography and Seismocardiography in Parabolic Flight: Preliminary Results from the ESA B3D Project

    NASA Astrophysics Data System (ADS)

    Migeotte, P.-F.; De Ridder, S.; Neyt, X.; Pattyn, N.; Di Rienzo, M.; Beck, L.; Gauger, P.; Limper, U.; Prisk, G. K.; Rusanov, V.; Funtova, I.; Baevsky, R. M.; Tank, J.

    2013-02-01

    Ballistocardiography (BCG) is a technique that had a large interest in cardiology between the fifties and eighties. Typically BCG consisted in the recording of mechanical acceleration (Acc), caused by cardiac activity, on a subject lying on a table. As Acc was recorded only in the 2-dimensions (2D) of the horizontal plane, the antero-posterior (Z-axis) component was often neglected. From past experiments conducted in space [1,2] it was suggested that this component was comparable in magnitude to the other two and that Ballistocardiography should be recorded in three dimensions (3D). These observations and the recent modest regain of interest in the BCG technique were the starting point of the B3D project selected by ESA for the definition phase after the AO-2009. We recorded 3D Acc at various positions on the surface of the body (close to the centre of mass (CM), at the apex of the heart and on the sternum) of 8 healthy volunteers during free floating periods of parabolic flight (PF) manoeuvre (ESA 55th and DLR 19th PF campaigns conducted on-board the A300-zéroG airplane of NOVESPACE). Out of the many recordings collected, only a very limited number provided body Acc free from artefacts. Nevertheless, our results show that Seismocardiograms (SCG) and Ballistocardiograms (BCG) waves were qualitatively and quantitatively comparable in the frontal plane while larger differences were present along the antero-posterior component. Our limited number of artefact free episodes demonstrates the intrinsic difficulties of 3D recordings of SCG and BCG in PF and thus the need for a study in sustained microgravity. Moreover, our results confirm that the ventro-dorsal component of BCG is of similar amplitude as the other two which further demonstrates that the three components are essential to provide a physiological interpretation of BCG and SCG signals.

  4. A Microfluidic DNA Sensor Based on Three-Dimensional (3D) Hierarchical MoS2/Carbon Nanotube Nanocomposites

    PubMed Central

    Yang, Dahou; Tayebi, Mahnoush; Huang, Yinxi; Yang, Hui Ying; Ai, Ye

    2016-01-01

    In this work, we present a novel microfluidic biosensor for sensitive fluorescence detection of DNA based on 3D architectural MoS2/multi-walled carbon nanotube (MWCNT) nanocomposites. The proposed platform exhibits a high sensitivity, selectivity, and stability with a visible manner and operation simplicity. The excellent fluorescence quenching stability of a MoS2/MWCNT aqueous solution coupled with microfluidics will greatly simplify experimental steps and reduce time for large-scale DNA detection. PMID:27854247

  5. Three-Dimensional (3-D) Atom Probe Tomography of a Cu-Precipitation-Strengthened, Ultrahigh-Strength Carburized Steel

    NASA Astrophysics Data System (ADS)

    Tiemens, Benjamin L.; Sachdev, Anil K.; Mishra, Raja K.; Olson, Gregory B.

    2012-10-01

    In an effort to reduce material cost, experimental steel alloys were developed that incorporated Cu precipitation in lieu of costly Co alloying additions in secondary hardening carburizing gear steels. This work utilizes three-dimensional atom probe tomography to study one of these prototype alloys and quantify the nanoscale dispersions of body-centered cubic (bcc) Cu and M2C alloy carbides used to strengthen these steels. The temporal evolution of precipitate, size, morphology, and interprecipitate interactions were studied for various tempering times. Findings suggest that Cu precipitation does act as a catalyst for heterogeneous nucleation of M2C carbides at relatively high hardness levels; however, the resultant volume fraction of strengthening carbides was noticeably less than that predicted by thermodynamic equilibrium calculations, indicating a reduced potency compared with Co-assisted precipitation. Microstructural information such as precipitate size and volume fraction was measured at the peak hardness condition and successfully used to recalibrate alloy design models for subsequent alloy design iterations.

  6. Revolutionising incoherent scatter science with EISCAT_3D: A European three-dimensional imaging radar for atmospheric and geospace research

    NASA Astrophysics Data System (ADS)

    Turunen, Esa; McCrea, Ian; Kosch, Mike

    2010-05-01

    EISCAT_3D will be Europe's next-generation radar for the study of the high-latitude atmosphere and geospace, located in northern Fenno-Scandinavia, with capabilities going well beyond anything currently available to the international research community. The facility will consist of several very large active phased-array antenna transmitters/receivers, and multiple passive sites located in three countries. Depending on the available funding, EISCAT_3D will be comprised of tens of thousands, up to more than 100 000, individual antenna elements. EISCAT_3D combines several key attributes which have never before been available together in a single radar, such as volumetric imaging and tracking, aperture synthesis imaging, multistatic configuration, improved sensitivity and transmitter flexibility. The use of advanced beam-forming technology allows the beam direction to be switched in milliseconds, rather than the minutes which it can take to re-position dish-based radars. This allows very wide spatial coverage to be obtained, by interleaving multiple beam directions to carry out quasi-simultaneous volumetric imaging. It also allows objects such as satellites and space debris to be tracked across the sky. At the passive sites, the design allows for at least five simultaneous beams at full bandwidth, rising to over twenty beams if the bandwidth is limited to the ion line, allowing the whole range of the transmitted beam to be imaged from each passive site, using holographic radar techniques. EISCAT_3D has a modular configuration, which allows an active array to be split into smaller elements to be used for aperture synthesis imaging. The result will be an entirely new data product, consisting of range-dependent images of small sub-beamwidth scale structures, with sizes down to 20 m. EISCAT_3D will be the first phased array incoherent scatter radar to use a multistatic configuration. A minimum of five radar sites, consisting of two pairs located around 120 km and 250 km

  7. A three-dimensional image processing program for accurate, rapid, and semi-automated segmentation of neuronal somata with dense neurite outgrowth

    PubMed Central

    Ross, James D.; Cullen, D. Kacy; Harris, James P.; LaPlaca, Michelle C.; DeWeerth, Stephen P.

    2015-01-01

    Three-dimensional (3-D) image analysis techniques provide a powerful means to rapidly and accurately assess complex morphological and functional interactions between neural cells. Current software-based identification methods of neural cells generally fall into two applications: (1) segmentation of cell nuclei in high-density constructs or (2) tracing of cell neurites in single cell investigations. We have developed novel methodologies to permit the systematic identification of populations of neuronal somata possessing rich morphological detail and dense neurite arborization throughout thick tissue or 3-D in vitro constructs. The image analysis incorporates several novel automated features for the discrimination of neurites and somata by initially classifying features in 2-D and merging these classifications into 3-D objects; the 3-D reconstructions automatically identify and adjust for over and under segmentation errors. Additionally, the platform provides for software-assisted error corrections to further minimize error. These features attain very accurate cell boundary identifications to handle a wide range of morphological complexities. We validated these tools using confocal z-stacks from thick 3-D neural constructs where neuronal somata had varying degrees of neurite arborization and complexity, achieving an accuracy of ≥95%. We demonstrated the robustness of these algorithms in a more complex arena through the automated segmentation of neural cells in ex vivo brain slices. These novel methods surpass previous techniques by improving the robustness and accuracy by: (1) the ability to process neurites and somata, (2) bidirectional segmentation correction, and (3) validation via software-assisted user input. This 3-D image analysis platform provides valuable tools for the unbiased analysis of neural tissue or tissue surrogates within a 3-D context, appropriate for the study of multi-dimensional cell-cell and cell-extracellular matrix interactions. PMID

  8. Three-dimensional (3D) plasmonic hot spots for label-free sensing and effective photothermal killing of multiple drug resistant superbugs.

    PubMed

    Jones, Stacy; Sinha, Sudarson Sekhar; Pramanik, Avijit; Ray, Paresh Chandra

    2016-11-03

    Drug resistant superbug infection is one of the foremost threats to human health. Plasmonic nanoparticles can be used for ultrasensitive bio-imaging and photothermal killing by amplification of electromagnetic fields at nanoscale "hot spots". One of the main challenges to plasmonic imaging and photothermal killing is design of a plasmonic substrate with a large number of "hot spots". Driven by this need, this article reports design of a three-dimensional (3D) plasmonic "hot spot"-based substrate using gold nanoparticle attached hybrid graphene oxide (GO), free from the traditional 2D limitations. Experimental results show that the 3D substrate has capability for highly sensitive label-free sensing and generates high photothermal heat. Reported data using p-aminothiophenol conjugated 3D substrate show that the surface enhanced Raman spectroscopy (SERS) enhancement factor for the 3D "hot spot"-based substrate is more than two orders of magnitude greater than that for the two-dimensional (2D) substrate and five orders of magnitude greater than that for the zero-dimensional (0D) p-aminothiophenol conjugated gold nanoparticle. 3D-Finite-Difference Time-Domain (3D-FDTD) simulation calculations indicate that the SERS enhancement factor can be greater than 10(4) because of the bent assembly structure in the 3D substrate. Results demonstrate that the 3D-substrate-based SERS can be used for fingerprint identification of several multi-drug resistant superbugs with detection limits of 5 colony forming units per mL. Experimental data show that 785 nm near infrared (NIR) light generates around two times more photothermal heat for the 3D substrate with respect to the 2D substrate, and allows rapid and effective killing of 100% of the multi-drug resistant superbugs within 5 minutes.

  9. Development of methods for accurate modeling of optical equipment for three-dimensional printing

    NASA Astrophysics Data System (ADS)

    Saitgalina, A. K.; Tolstoba, N. D.; Mitiushkin, A. V.

    2016-09-01

    The task of this research project is to define the extent of applicability of such 3D self-manufacture approach to the production of optical fastenings. The resulting lack of equipment, to be used for demonstration of simple experiments, which would be both competitive in performance and cheap to produce, led to the decision to research opportunities for self-manufacturing.

  10. Three-dimensional (3D) GIS-based coastline change analysis and display using LIDAR series data

    NASA Astrophysics Data System (ADS)

    Zhou, G.

    This paper presents a method to visualize and analyze topography and topographic changes on coastline area. The study area, Assantage Island Nation Seashore (AINS), is located along a 37-mile stretch of Assateague Island National Seashore in Eastern Shore, VA. The DEMS data sets from 1996 through 2000 for various time intervals, e.g., year-to-year, season-to-season, date-to-date, and a four year (1996-2000) are created. The spatial patterns and volumetric amounts of erosion and deposition of each part on a cell-by-cell basis were calculated. A 3D dynamic display system using ArcView Avenue for visualizing dynamic coastal landforms has been developed. The system was developed into five functional modules: Dynamic Display, Analysis, Chart analysis, Output, and Help. The Display module includes five types of displays: Shoreline display, Shore Topographic Profile, Shore Erosion Display, Surface TIN Display, and 3D Scene Display. Visualized data include rectified and co-registered multispectral Landsat digital image and NOAA/NASA ATM LIDAR data. The system is demonstrated using multitemporal digital satellite and LIDAR data for displaying changes on the Assateague Island National Seashore, Virginia. The analyzed results demonstrated that a further understanding to the study and comparison of the complex morphological changes that occur naturally or human-induced on barrier islands is required.

  11. AUTOMATED, HIGHLY ACCURATE VERIFICATION OF RELAP5-3D

    SciTech Connect

    George L Mesina; David Aumiller; Francis Buschman

    2014-07-01

    Computer programs that analyze light water reactor safety solve complex systems of governing, closure and special process equations to model the underlying physics. In addition, these programs incorporate many other features and are quite large. RELAP5-3D[1] has over 300,000 lines of coding for physics, input, output, data management, user-interaction, and post-processing. For software quality assurance, the code must be verified and validated before being released to users. Verification ensures that a program is built right by checking that it meets its design specifications. Recently, there has been an increased importance on the development of automated verification processes that compare coding against its documented algorithms and equations and compares its calculations against analytical solutions and the method of manufactured solutions[2]. For the first time, the ability exists to ensure that the data transfer operations associated with timestep advancement/repeating and writing/reading a solution to a file have no unintended consequences. To ensure that the code performs as intended over its extensive list of applications, an automated and highly accurate verification method has been modified and applied to RELAP5-3D. Furthermore, mathematical analysis of the adequacy of the checks used in the comparisons is provided.

  12. Three-dimensional image technology in forensic anthropology: Assessing the validity of biological profiles derived from CT-3D images of the skeleton

    NASA Astrophysics Data System (ADS)

    Garcia de Leon Valenzuela, Maria Julia

    This project explores the reliability of building a biological profile for an unknown individual based on three-dimensional (3D) images of the individual's skeleton. 3D imaging technology has been widely researched for medical and engineering applications, and it is increasingly being used as a tool for anthropological inquiry. While the question of whether a biological profile can be derived from 3D images of a skeleton with the same accuracy as achieved when using dry bones has been explored, bigger sample sizes, a standardized scanning protocol and more interobserver error data are needed before 3D methods can become widely and confidently used in forensic anthropology. 3D images of Computed Tomography (CT) scans were obtained from 130 innominate bones from Boston University's skeletal collection (School of Medicine). For each bone, both 3D images and original bones were assessed using the Phenice and Suchey-Brooks methods. Statistical analysis was used to determine the agreement between 3D image assessment versus traditional assessment. A pool of six individuals with varying experience in the field of forensic anthropology scored a subsample (n = 20) to explore interobserver error. While a high agreement was found for age and sex estimation for specimens scored by the author, the interobserver study shows that observers found it difficult to apply standard methods to 3D images. Higher levels of experience did not result in higher agreement between observers, as would be expected. Thus, a need for training in 3D visualization before applying anthropological methods to 3D bones is suggested. Future research should explore interobserver error using a larger sample size in order to test the hypothesis that training in 3D visualization will result in a higher agreement between scores. The need for the development of a standard scanning protocol focusing on the optimization of 3D image resolution is highlighted. Applications for this research include the possibility

  13. Development of a 12-Item Abbreviated Three-Dimensional Wisdom Scale (3D-WS-12): Item Selection and Psychometric Properties.

    PubMed

    Thomas, Michael L; Bangen, Katherine J; Ardelt, Monika; Jeste, Dilip V

    2017-01-01

    Wisdom has been reported to be associated with better mental health and quality of life among older adults. Over the past decades, there has been considerable growth in empirical research on wisdom, including the development of standardized measures. The 39-item Three-Dimensional Wisdom Scale (3D-WS) is a useful assessment tool, given its rigorous development and good psychometric properties. However, the measure's length can prohibit use. In this article, we used a sample of 1,546 community-dwelling adults aged 21 to 100 years (M = 66 years) from the Successful AGing Evaluation (SAGE) study to develop an abbreviated 12-item version of the 3D-WS: the 3D-WS-12. Balancing concerns for measurement precision, internal structure, and content validity, factor analytic methods and expert judgment were used to identify a subset of 12-items for the 3D-WS-12. Results suggest that the 3D-WS-12 can provide efficient and valid assessments of Wisdom within the context of epidemiological surveys.

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

    NASA Technical Reports Server (NTRS)

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

    1990-01-01

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

  15. Empirical and accurate method for the three-dimensional electrostatic potential (EM-ESP) of biomolecules.

    PubMed

    Du, Qi-Shi; Wang, Cheng-Hua; Wang, Yu-Ting; Huang, Ri-Bo

    2010-04-01

    The electrostatic potential (ESP) is an important property of interactions within and between macromolecules, including those of importance in the life sciences. Semiempirical quantum chemical methods and classical Coulomb calculations fail to provide even qualitative ESP for many of these biomolecules. A new empirical ESP calculation method, namely, EM-ESP, is developed in this study, in which the traditional approach of point atomic charges and the classical Coulomb equation is discarded. In its place, the EM-ESP generates a three-dimensional electrostatic potential V(EM)(r) in molecular space that is the sum of contributions from all component atoms. The contribution of an atom k is formulated as a Gaussian function g(r(k);alpha(k),beta(k)) = alpha(k)/r(k)(betak) with two parameters (alpha(k) and beta(k)). The benchmark for the parameter optimization is the ESP obtained by using higher-level quantum chemical approaches (e.g., CCSD/TZVP). A set of atom-based parameters is optimized in a training set of common organic molecules. Calculated examples demonstrate that the EM-ESP approach is a vast improvement over the Coulombic approach in producing the molecular ESP contours that are comparable to the results obtained with higher-level quantum chemical methods. The atom-based parameters are shown to be transferrable between one part of closely related aromatic molecules. The atom-based ESP formulization and parametrization strategy can be extended to biological macromolecules, such as proteins, DNA, and RNA molecules. Since ESP is frequently used to rationalize and predict intermolecular interactions, we expect that the EM-ESP method will have important applications for studies of protein-ligand and protein-protein interactions in numerous areas of chemistry, molecular biology, and other life sciences.

  16. Three dimensional electrical conductivity model of the Northwestern US derived from 3-D inversion of USArray magnetotelluric data

    NASA Astrophysics Data System (ADS)

    Meqbel, N. M.; Egbert, G. D.; Kelbert, A.

    2011-12-01

    Long period (10-20,000 s) magnetotelluric (MT) data are being acquired in a series of temporary arrays deployed across the continental United States through the EMScope component of EarthScope. MT deployments in 2006-2011 have acquired data at 325 sites on an approximately regular grid, with the same nominal spacing as the USArray broadband seismic transportable array (~70 km). The MT sites span a rectangular area from NW Washington to NW Colorado. Here we present results of a 3-D inversion of the full data set. A number of conductive and resistive features appear consistently in the crust and upper mantle in essentially all of a large suite of 3-D inverse solutions. Extensive areas of high conductivity are found in the lower crust (up to a depth of ~ 40 km) beneath the Basin & Range in southeastern Oregon, as imaged by Patro and Egbert (2008). In our new model, this feature extends further to the south and to the east, where it merges with somewhat deeper (uppermost mantle) conductivities beneath the Yellowstone-Snake River Plain. This deeper feature, which extends from Yellowstone to the SW into northeastern Nevada, coincides with the track of the Yellowstone hotspot discussed e.g., in Smith et. al. (2008). The lower crust and the uppermost mantle in the northeastern part of the domain, covering the area from eastern Washington to Montana and continuing south to Wyoming, is generally resistive, with a few localized exceptions. This resistive zone coincides with high velocities discussed and interpreted, e.g., by Yang et. al. (2008) as thick, stable Proterozoic lithosphere. A number of large-scale anomalous features also appear consistently in the upper mantle, at depths of ~ 50 km to 300 km. Most striking is a zone of high resistivity on the western edge of the domain, beneath western Oregon, Washington and northern California in the area occupied by oceanic lithosphere of the Juan de Fuca Plate, which has subducted beneath the relatively more conductive

  17. Three dimensional printing as an effective method of producing anatomically accurate models for studies in thermal ecology.

    PubMed

    Watson, Charles M; Francis, Gamal R

    2015-07-01

    Hollow copper models painted to match the reflectance of the animal subject are standard in thermal ecology research. While the copper electroplating process results in accurate models, it is relatively time consuming, uses caustic chemicals, and the models are often anatomically imprecise. Although the decreasing cost of 3D printing can potentially allow the reproduction of highly accurate models, the thermal performance of 3D printed models has not been evaluated. We compared the cost, accuracy, and performance of both copper and 3D printed lizard models and found that the performance of the models were statistically identical in both open and closed habitats. We also find that 3D models are more standard, lighter, durable, and inexpensive, than the copper electroformed models.

  18. Improving sample distribution homogeneity in Three-Dimensional Microfluidic Paper-Based Analytical Devices (3D-μPAD) by rational device design.

    PubMed

    Morbioli, Giorgio Gianini; Mazzu-Nascimento, Thiago; Milan, Luis Aparecido; Stockton, Amanda M; Carrilho, Emanuel

    2017-04-12

    Paper-based devices are a portable, user-friendly and affordable technology that is one of the best analytical tools for inexpensive diagnostic devices. Three-dimensional microfluidic paper-based analytical devices (3D-μPADs) are an evolution of single layer devices and they permit effective sample dispersion, individual layer treatment, and multiplex analytical assays. Here, we present the rational design of a wax-printed 3D-μPAD that enables more homogeneous permeation of fluids along the cellulose matrix than other existing designs in the literature. Moreover, we show the importance of the rational design of channels on these devices using glucose oxidase, peroxidase, and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) reactions. We present an alternative method for layer stacking using a magnetic apparatus, which facilitates fluidic dispersion and improves the reproducibility of tests performed on 3D-μPADs. We also provide the optimized designs for printing, facilitating further studies using 3D-μPADs.

  19. A study on the reproducibility of cephalometric landmarks when undertaking a three-dimensional (3D) cephalometric analysis

    PubMed Central

    Llamas, José M.; Cibrián, Rosa; Gandia, José L.; Paredes, Vanessa

    2012-01-01

    Objectives: Cone Beam Computerized Tomography (CBCT) allows the possibility of modifying some of the diagnostic tools used in orthodontics, such as cephalometry. The first step must be to study the characteristics of these devices in terms of accuracy and reliability of the most commonly used landmarks. The aims were 1- To assess intra and inter-observer reliability in the location of anatomical landmarks belonging to hard tissues of the skull in images taken with a CBCT device, 2- To determine which of those landmarks are more vs. less reliable and 3- To introduce planes of reference so as to create cephalometric analyses appropriated to the 3D reality. Study design: Fifteen patients who had a CBCT (i-CAT®) as a diagnostic register were selected. To assess the reproducibility on landmark location and the differences in the measurements of two observers at different times, 41 landmarks were defined on the three spatial axes (X,Y,Z) and located. 3.690 measurements were taken and, as each determination has 3 coordinates, 11.070 data were processed with SPSS® statistical package. To discover the reproducibility of the method on landmark location, an ANOVA was undertaken using two variation factors: time (t1, t2 and t3) and observer (Ob1 and Ob2) for each axis (X, Y and Z) and landmark. The order of the CBCT scans submitted to the observers (Ob1, Ob2) at t1, t2, and t3, were different and randomly allocated. Multiple comparisons were undertaken using the Bonferroni test. The intra- and inter-examiner ICC´s were calculated. Results: Intra- and inter-examiner reliability was high, both being ICC ≥ 0.99, with the best frequency on axis Z. Conclusions: The most reliable landmarks were: Nasion, Sella, Basion, left Porion, point A, anterior nasal spine, Pogonion, Gnathion, Menton, frontozygomatic sutures, first lower molars and upper and lower incisors. Those with less reliability were the supraorbitals, right zygion and posterior nasal spine. Key words:Cone Beam

  20. Anthropometric precision and accuracy of digital three-dimensional photogrammetry: comparing the Genex and 3dMD imaging systems with one another and with direct anthropometry.

    PubMed

    Weinberg, Seth M; Naidoo, Sybill; Govier, Daniel P; Martin, Rick A; Kane, Alex A; Marazita, Mary L

    2006-05-01

    A variety of commercially available three-dimensional (3D) surface imaging systems are currently in use by craniofacial specialists. Little is known, however, about how measurement data generated from alternative 3D systems compare, specifically in terms of accuracy and precision. The purpose of this study was to compare anthropometric measurements obtained by way of two different digital 3D photogrammetry systems (Genex and 3dMD) as well as direct anthropometry and to evaluate intraobserver precision across these three methods. On a sample of 18 mannequin heads, 12 linear distances were measured twice by each method. A two-factor repeated measures analysis of variance was used to test simultaneously for mean differences in precision across methods. Additional descriptive statistics (e.g., technical error of measurement [TEM]) were used to quantify measurement error magnitude. Statistically significant (P < 0.05) mean differences were observed across methods for nine anthropometric variables; however, the magnitude of these differences was consistently at the submillimeter level. No significant differences were noted for precision. Moreover, the magnitude of imprecision was determined to be very small, with TEM scores well under 1 mm, and intraclass correlation coefficients ranging from 0.98 to 1. Results indicate that overall mean differences across these three methods were small enough to be of little practical importance. In terms of intraobserver precision, all methods fared equally well. This study is the first attempt to simultaneously compare 3D surface imaging systems directly with one another and with traditional anthropometry. Results suggest that craniofacial surface data obtained by way of alternative 3D photogrammetric systems can be combined or compared statistically.

  1. Accurate Adaptive Level Set Method and Sharpening Technique for Three Dimensional Deforming Interfaces

    NASA Technical Reports Server (NTRS)

    Kim, Hyoungin; Liou, Meng-Sing

    2011-01-01

    In this paper, we demonstrate improved accuracy of the level set method for resolving deforming interfaces by proposing two key elements: (1) accurate level set solutions on adapted Cartesian grids by judiciously choosing interpolation polynomials in regions of different grid levels and (2) enhanced reinitialization by an interface sharpening procedure. The level set equation is solved using a fifth order WENO scheme or a second order central differencing scheme depending on availability of uniform stencils at each grid point. Grid adaptation criteria are determined so that the Hamiltonian functions at nodes adjacent to interfaces are always calculated by the fifth order WENO scheme. This selective usage between the fifth order WENO and second order central differencing schemes is confirmed to give more accurate results compared to those in literature for standard test problems. In order to further improve accuracy especially near thin filaments, we suggest an artificial sharpening method, which is in a similar form with the conventional re-initialization method but utilizes sign of curvature instead of sign of the level set function. Consequently, volume loss due to numerical dissipation on thin filaments is remarkably reduced for the test problems

  2. Three-dimensional (3D) microstructural characterization and quantification of reflow porosity in Sn-rich alloy/copper joints by X-ray tomography

    SciTech Connect

    Jiang Ling; Chawla, Nikhilesh; Pacheco, Mario; Noveski, Vladimir

    2011-10-15

    In this paper high resolution X-ray tomography was used to characterize reflow porosity in Sn-3.9Ag-0.7Cu/Cu solder joints. The combination of two segmentation techniques was applied for the three-dimensional (3D) visualization of pores in the joints and the quantification on the characteristics of reflow porosity, including pore size, volume fraction and morphology. The size, morphology and distribution of porosity were visualized in 3D for three different solder joints. Since the results are relatively similar for all three, only the results of one joint are presented. Solder reflow porosity was mostly spherical, segregated along the solder/Cu interface, and had an average pore size of 30 {mu}m in diameter. A few large pores (larger than 100 {mu}m in diameter) were present, some of which had lower sphericity, i.e., they were more irregular. The presence of these large pores may significantly influence the mechanical behavior of solder joints. - Highlights: {yields} Non-destructive 3D characterization and quantification of porosity in Pb-free solders by X-ray tomography {yields} Two new image analysis and reconstruction tools are presented that can be used by the community at large {yields} Pore size, volume fraction, and sphericity, is critical to understanding microstructure and modeling of these systems.

  3. Three-dimensional scanning near field optical microscopy (3D-SNOM) imaging of random arrays of copper nanoparticles: implications for plasmonic solar cell enhancement.

    PubMed

    Ezugwu, Sabastine; Ye, Hanyang; Fanchini, Giovanni

    2015-01-07

    In order to investigate the suitability of random arrays of nanoparticles for plasmonic enhancement in the visible-near infrared range, we introduced three-dimensional scanning near-field optical microscopy (3D-SNOM) imaging as a useful technique to probe the intensity of near-field radiation scattered by random systems of nanoparticles at heights up to several hundred nm from their surface. We demonstrated our technique using random arrays of copper nanoparticles (Cu-NPs) at different particle diameter and concentration. Bright regions in the 3D-SNOM images, corresponding to constructive interference of forward-scattered plasmonic waves, were obtained at heights Δz ≥ 220 nm from the surface for random arrays of Cu-NPs of ∼ 60-100 nm in diameter. These heights are too large to use Cu-NPs in contact of the active layer for light harvesting in thin organic solar cells, which are typically no thicker than 200 nm. Using a 200 nm transparent spacer between the system of Cu-NPs and the solar cell active layer, we demonstrate that forward-scattered light can be conveyed in 200 nm thin film solar cells. This architecture increases the solar cell photoconversion efficiency by a factor of 3. Our 3D-SNOM technique is general enough to be suitable for a large number of other applications in nanoplasmonics.

  4. NIKE3D a nonlinear, implicit, three-dimensional finite element code for solid and structural mechanics user's manual update summary

    SciTech Connect

    Puso, M; Maker, B N; Ferencz, R M; Hallquist, J O

    2000-03-24

    This report provides the NIKE3D user's manual update summary for changes made from version 3.0.0 April 24, 1995 to version 3.3.6 March 24,2000. The updates are excerpted directly from the code printed output file (hence the Courier font and formatting), are presented in chronological order and delineated by NIKE3D version number. NIKE3D is a fully implicit three-dimensional finite element code for analyzing the finite strain static and dynamic response of inelastic solids, shells, and beams. Spatial discretization is achieved by the use of 8-node solid elements, 2-node truss and beam elements, and 4-node membrane and shell elements. Thirty constitutive models are available for representing a wide range of elastic, plastic, viscous, and thermally dependent material behavior. Contact-impact algorithms permit gaps, frictional sliding, and mesh discontinuities along material interfaces. Several nonlinear solution strategies are available, including Full-, Modified-, and Quasi-Newton methods. The resulting system of simultaneous linear equations is either solved iteratively by an element-by-element method, or directly by a direct factorization method.

  5. Using three-dimensional 3D grazing-incidence small-angle X-ray scattering (GISAXS) analysis to probe pore deformation in mesoporous silica films.

    PubMed

    Panduro, Elvia Anabela Chavez; Granlund, Håvard; Sztucki, Michael; Konovalov, Oleg; Breiby, Dag W; Gibaud, Alain

    2014-02-26

    In the past decade, remarkable progress has been made in studying nanoscale objects deposited on surfaces by grazing-incidence small-angle X-ray scattering (GISAXS). However, unravelling the structural properties of mesostructured thin films containing highly organized internal three-dimensional (3D) structures remains a challenging issue, because of the lack of efficient algorithms that allow prediction of the GISAXS intensity patterns. Previous attempts to calculate intensities have mostly been limited to cases of two-dimensional (2D) assemblies of nanoparticles at surfaces, or have been adapted to specific 3D cases. Here, we demonstrate that highly organized 3D mesoscale structures (for example, porous networks) can be modeled by the combined use of established crystallography formalism and the Distorted Wave Born Approximation (DWBA). Taking advantage of the near-zero intensity of symmetry-allowed Bragg reflections, the casual extinction or existence of certain reflections related to the anisotropy of the form factor of the pores can be used as a highly sensitive method to extract structural information. We employ this generic method to probe the slightly compressed anisotropic shape and orientation of pores in a mesoporous silica thin film having P63/mmc symmetry.

  6. The meaning and measurement of work fatigue: Development and evaluation of the Three-Dimensional Work Fatigue Inventory (3D-WFI).

    PubMed

    Frone, Michael R; Tidwell, Marie-Cecile O

    2015-07-01

    Although work fatigue represents an important construct in several substantive areas, prior conceptual definitions and measures have been inadequate in a number of ways. The goals of the present study were to develop a conceptual definition and outline the desirable characteristics of a work fatigue measure, briefly examine several prior measures of work fatigue-related constructs, and develop and evaluate a new measure of work fatigue. The Three-Dimensional Work Fatigue Inventory (3D-WFI) provides separate and commensurate assessments of physical, mental, and emotional work fatigue. Results from a pilot study (n = 207) and a broader evaluative study of U.S. wage and salary workers (n = 2,477) suggest that the 3D-WFI is psychometrically sound and evinces a meaningful pattern of relations with variables that comprise the nomological network of work fatigue. As with all new measures, additional research is required to evaluate fully the utility of the 3D-WFI in research on work fatigue.

  7. Role of surfactant during microemulsion photopolymerization for the creation of three-dimensional (3D) liquid crystal elastomer microsphere spatial cell scaffolds

    NASA Astrophysics Data System (ADS)

    Hegmann, Elda; Bera, Tanmay; Malcuit, Christopher; Clements, Robert

    2016-06-01

    Three-dimensional (3D) cell scaffolds based on connected nematic liquid crystal elastomer microsphere architectures support the attachment and proliferation of C2C12 myoblasts, neuroblastomas (SHSY5Y) and human dermal fibroblasts (hDF). The microsphere spatial cell scaffolds were prepared by an oil-in-water microemulsion photopolymerization of reactive nematic mesogens in the presence of various surfactants, and the as-prepared scaffold constructs are composed of smooth surface microspheres with diameter ranging from 10 to 30 μm. We here investigate how the nature and type of surfactant used during the microemulsion photopolymerization impacts both the size and size distribution of the resulting microspheres as well as their surface morphology, i.e. the surface roughness.

  8. Validation of the RPLUS3D Code for Supersonic Inlet Applications Involving Three-Dimensional Shock Wave-Boundary Layer Interactions

    NASA Technical Reports Server (NTRS)

    Kapoor, Kamlesh; Anderson, Bernhard H.; Shaw, Robert J.

    1994-01-01

    A three-dimensional computational fluid dynamics code, RPLUS3D, which was developed for the reactive propulsive flows of ramjets and scramjets, was validated for glancing shock wave-boundary layer interactions. Both laminar and turbulent flows were studied. A supersonic flow over a wedge mounted on a flat plate was numerically simulated. For the laminar case, the static pressure distribution, velocity vectors, and particle traces on the flat plate were obtained. For turbulent flow, both the Baldwin-Lomax and Chien two-equation turbulent models were used. The static pressure distributions, pitot pressure, and yaw angle profiles were computed. In addition, the velocity vectors and particle traces on the flat plate were also obtained from the computed solution. Overall, the computed results for both laminar and turbulent cases compared very well with the experimentally obtained data.

  9. INS3D - NUMERICAL SOLUTION OF THE INCOMPRESSIBLE NAVIER-STOKES EQUATIONS IN THREE-DIMENSIONAL GENERALIZED CURVILINEAR COORDINATES (IBM VERSION)

    NASA Technical Reports Server (NTRS)

    Kwak, D.

    1994-01-01

    INS3D computes steady-state solutions to the incompressible Navier-Stokes equations. The INS3D approach utilizes pseudo-compressibility combined with an approximate factorization scheme. This computational fluid dynamics (CFD) code has been verified on problems such as flow through a channel, flow over a backwardfacing step and flow over a circular cylinder. Three dimensional cases include flow over an ogive cylinder, flow through a rectangular duct, wind tunnel inlet flow, cylinder-wall juncture flow and flow through multiple posts mounted between two plates. INS3D uses a pseudo-compressibility approach in which a time derivative of pressure is added to the continuity equation, which together with the momentum equations form a set of four equations with pressure and velocity as the dependent variables. The equations' coordinates are transformed for general three dimensional applications. The equations are advanced in time by the implicit, non-iterative, approximately-factored, finite-difference scheme of Beam and Warming. The numerical stability of the scheme depends on the use of higher-order smoothing terms to damp out higher-frequency oscillations caused by second-order central differencing. The artificial compressibility introduces pressure (sound) waves of finite speed (whereas the speed of sound would be infinite in an incompressible fluid). As the solution converges, these pressure waves die out, causing the derivation of pressure with respect to time to approach zero. Thus, continuity is satisfied for the incompressible fluid in the steady state. Computational efficiency is achieved using a diagonal algorithm. A block tri-diagonal option is also available. When a steady-state solution is reached, the modified continuity equation will satisfy the divergence-free velocity field condition. INS3D is capable of handling several different types of boundaries encountered in numerical simulations, including solid-surface, inflow and outflow, and far

  10. INS3D - NUMERICAL SOLUTION OF THE INCOMPRESSIBLE NAVIER-STOKES EQUATIONS IN THREE-DIMENSIONAL GENERALIZED CURVILINEAR COORDINATES (DEC RISC ULTRIX VERSION)

    NASA Technical Reports Server (NTRS)

    Biyabani, S. R.

    1994-01-01

    INS3D computes steady-state solutions to the incompressible Navier-Stokes equations. The INS3D approach utilizes pseudo-compressibility combined with an approximate factorization scheme. This computational fluid dynamics (CFD) code has been verified on problems such as flow through a channel, flow over a backwardfacing step and flow over a circular cylinder. Three dimensional cases include flow over an ogive cylinder, flow through a rectangular duct, wind tunnel inlet flow, cylinder-wall juncture flow and flow through multiple posts mounted between two plates. INS3D uses a pseudo-compressibility approach in which a time derivative of pressure is added to the continuity equation, which together with the momentum equations form a set of four equations with pressure and velocity as the dependent variables. The equations' coordinates are transformed for general three dimensional applications. The equations are advanced in time by the implicit, non-iterative, approximately-factored, finite-difference scheme of Beam and Warming. The numerical stability of the scheme depends on the use of higher-order smoothing terms to damp out higher-frequency oscillations caused by second-order central differencing. The artificial compressibility introduces pressure (sound) waves of finite speed (whereas the speed of sound would be infinite in an incompressible fluid). As the solution converges, these pressure waves die out, causing the derivation of pressure with respect to time to approach zero. Thus, continuity is satisfied for the incompressible fluid in the steady state. Computational efficiency is achieved using a diagonal algorithm. A block tri-diagonal option is also available. When a steady-state solution is reached, the modified continuity equation will satisfy the divergence-free velocity field condition. INS3D is capable of handling several different types of boundaries encountered in numerical simulations, including solid-surface, inflow and outflow, and far

  11. Validation of an Accurate Three-Dimensional Helical Slow-Wave Circuit Model

    NASA Technical Reports Server (NTRS)

    Kory, Carol L.

    1997-01-01

    The helical slow-wave circuit embodies a helical coil of rectangular tape supported in a metal barrel by dielectric support rods. Although the helix slow-wave circuit remains the mainstay of the traveling-wave tube (TWT) industry because of its exceptionally wide bandwidth, a full helical circuit, without significant dimensional approximations, has not been successfully modeled until now. Numerous attempts have been made to analyze the helical slow-wave circuit so that the performance could be accurately predicted without actually building it, but because of its complex geometry, many geometrical approximations became necessary rendering the previous models inaccurate. In the course of this research it has been demonstrated that using the simulation code, MAFIA, the helical structure can be modeled with actual tape width and thickness, dielectric support rod geometry and materials. To demonstrate the accuracy of the MAFIA model, the cold-test parameters including dispersion, on-axis interaction impedance and attenuation have been calculated for several helical TWT slow-wave circuits with a variety of support rod geometries including rectangular and T-shaped rods, as well as various support rod materials including isotropic, anisotropic and partially metal coated dielectrics. Compared with experimentally measured results, the agreement is excellent. With the accuracy of the MAFIA helical model validated, the code was used to investigate several conventional geometric approximations in an attempt to obtain the most computationally efficient model. Several simplifications were made to a standard model including replacing the helical tape with filaments, and replacing rectangular support rods with shapes conforming to the cylindrical coordinate system with effective permittivity. The approximate models are compared with the standard model in terms of cold-test characteristics and computational time. The model was also used to determine the sensitivity of various

  12. Accurate 3d Scanning of Damaged Ancient Greek Inscriptions for Revealing Weathered Letters

    NASA Astrophysics Data System (ADS)

    Papadaki, A. I.; Agrafiotis, P.; Georgopoulos, A.; Prignitz, S.

    2015-02-01

    In this paper two non-invasive non-destructive alternative techniques to the traditional and invasive technique of squeezes are presented alongside with specialized developed processing methods, aiming to help the epigraphists to reveal and analyse weathered letters in ancient Greek inscriptions carved in masonry or marble. The resulting 3D model would serve as a detailed basis for the epigraphists to try to decipher the inscription. The data were collected by using a Structured Light scanner. The creation of the final accurate three dimensional model is a complicated procedure requiring large computation cost and human effort. It includes the collection of geometric data in limited space and time, the creation of the surface, the noise filtering and the merging of individual surfaces. The use of structured light scanners is time consuming and requires costly hardware and software. Therefore an alternative methodology for collecting 3D data of the inscriptions was also implemented for reasons of comparison. Hence, image sequences from varying distances were collected using a calibrated DSLR camera aiming to reconstruct the 3D scene through SfM techniques in order to evaluate the efficiency and the level of precision and detail of the obtained reconstructed inscriptions. Problems in the acquisition processes as well as difficulties in the alignment step and mesh optimization are also encountered. A meta-processing framework is proposed and analysed. Finally, the results of processing and analysis and the different 3D models are critically inspected and then evaluated by a specialist in terms of accuracy, quality and detail of the model and the capability of revealing damaged and "hidden" letters.

  13. Soft-tissue volumetric changes following monobloc distraction procedure: analysis using digital three-dimensional photogrammetry system (3dMD).

    PubMed

    Chan, Fuan Chiang; Kawamoto, Henry K; Federico, Christina; Bradley, James P

    2013-03-01

    We have previously reported that monobloc advancement by distraction osteogenesis resulted in decreased morbidity and greater advancement with less relapse compared with acute monobloc advancement with bone grafting. In this study, we examine the three-dimensional (3D) volumetric soft-tissue changes in monobloc distraction.Patients with syndromic craniosynostosis who underwent monobloc distraction from 2002 to 2010 at University of California-Los Angeles Craniofacial Center were studied (n = 12). We recorded diagnosis, indications for the surgery, and volumetric changes for skeletal and soft-tissue midface structures (preoperative/postoperative [6 weeks]/follow-up [>1 year]). Computed tomography scans and a digital 3D photogrammetry system were used for image analysis.Patients ranged from 6 to 14 years of age (mean, 10.1 years) at the time of the operation (follow-up 2-11 years); mean distraction advancement was 19.4 mm (range, 14-25 mm). There was a mean increase in the 3D volumetric soft-tissue changes: 99.5 ± 4.0 cm(3) (P < 0.05) at 6 weeks and 94.9 ± 3.6 cm(3) (P < 0.05) at 1-year follow-up. When comparing soft-tissue changes at 6 weeks postoperative to 1-year follow-up, there were minimal relapse changes. The overall mean 3D skeletal change was 108.9 ± 4.2 cm. For every 1 cm of skeletal gain, there was 0.78 cm(3) of soft-tissue gain.Monobloc advancement by distraction osteogenesis using internal devices resulted in increased volumetric soft-tissue changes, which remained stable at 1 year. The positive linear correlation between soft-tissue increments and bony advancement can be incorporated during the planning of osteotomies to achieve optimum surgical outcomes with monobloc distraction.

  14. Imaging the Aqueous Humor Outflow Pathway in Human Eyes by Three-dimensional Micro-computed Tomography (3D micro-CT)

    SciTech Connect

    C Hann; M Bentley; A Vercnocke; E Ritman; M Fautsch

    2011-12-31

    The site of outflow resistance leading to elevated intraocular pressure in primary open-angle glaucoma is believed to be located in the region of Schlemm's canal inner wall endothelium, its basement membrane and the adjacent juxtacanalicular tissue. Evidence also suggests collector channels and intrascleral vessels may have a role in intraocular pressure in both normal and glaucoma eyes. Traditional imaging modalities limit the ability to view both proximal and distal portions of the trabecular outflow pathway as a single unit. In this study, we examined the effectiveness of three-dimensional micro-computed tomography (3D micro-CT) as a potential method to view the trabecular outflow pathway. Two normal human eyes were used: one immersion fixed in 4% paraformaldehyde and one with anterior chamber perfusion at 10 mmHg followed by perfusion fixation in 4% paraformaldehyde/2% glutaraldehyde. Both eyes were postfixed in 1% osmium tetroxide and scanned with 3D micro-CT at 2 {mu}m or 5 {mu}m voxel resolution. In the immersion fixed eye, 24 collector channels were identified with an average orifice size of 27.5 {+-} 5 {mu}m. In comparison, the perfusion fixed eye had 29 collector channels with a mean orifice size of 40.5 {+-} 13 {mu}m. Collector channels were not evenly dispersed around the circumference of the eye. There was no significant difference in the length of Schlemm's canal in the immersed versus the perfused eye (33.2 versus 35.1 mm). Structures, locations and size measurements identified by 3D micro-CT were confirmed by correlative light microscopy. These findings confirm 3D micro-CT can be used effectively for the non-invasive examination of the trabecular meshwork, Schlemm's canal, collector channels and intrascleral vasculature that comprise the distal outflow pathway. This imaging modality will be useful for non-invasive study of the role of the trabecular outflow pathway as a whole unit.

  15. Genome3D: A viewer-model framework for integrating and visualizing multi-scale epigenomic information within a three-dimensional genome

    PubMed Central

    2010-01-01

    Background New technologies are enabling the measurement of many types of genomic and epigenomic information at scales ranging from the atomic to nuclear. Much of this new data is increasingly structural in nature, and is often difficult to coordinate with other data sets. There is a legitimate need for integrating and visualizing these disparate data sets to reveal structural relationships not apparent when looking at these data in isolation. Results We have applied object-oriented technology to develop a downloadable visualization tool, Genome3D, for integrating and displaying epigenomic data within a prescribed three-dimensional physical model of the human genome. In order to integrate and visualize large volume of data, novel statistical and mathematical approaches have been developed to reduce the size of the data. To our knowledge, this is the first such tool developed that can visualize human genome in three-dimension. We describe here the major features of Genome3D and discuss our multi-scale data framework using a representative basic physical model. We then demonstrate many of the issues and benefits of multi-resolution data integration. Conclusions Genome3D is a software visualization tool that explores a wide range of structural genomic and epigenetic data. Data from various sources of differing scales can be integrated within a hierarchical framework that is easily adapted to new developments concerning the structure of the physical genome. In addition, our tool has a simple annotation mechanism to incorporate non-structural information. Genome3D is unique is its ability to manipulate large amounts of multi-resolution data from diverse sources to uncover complex and new structural relationships within the genome. PMID:20813045

  16. Three-dimensional scanning near field optical microscopy (3D-SNOM) imaging of random arrays of copper nanoparticles: implications for plasmonic solar cell enhancement

    NASA Astrophysics Data System (ADS)

    Ezugwu, Sabastine; Ye, Hanyang; Fanchini, Giovanni

    2014-11-01

    In order to investigate the suitability of random arrays of nanoparticles for plasmonic enhancement in the visible-near infrared range, we introduced three-dimensional scanning near-field optical microscopy (3D-SNOM) imaging as a useful technique to probe the intensity of near-field radiation scattered by random systems of nanoparticles at heights up to several hundred nm from their surface. We demonstrated our technique using random arrays of copper nanoparticles (Cu-NPs) at different particle diameter and concentration. Bright regions in the 3D-SNOM images, corresponding to constructive interference of forward-scattered plasmonic waves, were obtained at heights Δz >= 220 nm from the surface for random arrays of Cu-NPs of ~60-100 nm in diameter. These heights are too large to use Cu-NPs in contact of the active layer for light harvesting in thin organic solar cells, which are typically no thicker than 200 nm. Using a 200 nm transparent spacer between the system of Cu-NPs and the solar cell active layer, we demonstrate that forward-scattered light can be conveyed in 200 nm thin film solar cells. This architecture increases the solar cell photoconversion efficiency by a factor of 3. Our 3D-SNOM technique is general enough to be suitable for a large number of other applications in nanoplasmonics.In order to investigate the suitability of random arrays of nanoparticles for plasmonic enhancement in the visible-near infrared range, we introduced three-dimensional scanning near-field optical microscopy (3D-SNOM) imaging as a useful technique to probe the intensity of near-field radiation scattered by random systems of nanoparticles at heights up to several hundred nm from their surface. We demonstrated our technique using random arrays of copper nanoparticles (Cu-NPs) at different particle diameter and concentration. Bright regions in the 3D-SNOM images, corresponding to constructive interference of forward-scattered plasmonic waves, were obtained at heights Δz >= 220

  17. In situ investigation of high humidity stress corrosion cracking of 7075 aluminum alloy by three-dimensional (3D) X-ray synchrotron tomography

    SciTech Connect

    Singh, S. S.; Williams, J. J.; Lin, M. F.; Xiao, X.; De Carlo, F.; Chawla, N.

    2014-05-14

    In situ X-ray synchrotron tomography was used to investigate the stress corrosion cracking behavior of under-aged Al–Zn–Mg–Cu alloy in moisture. The discontinuous surface cracks (crack jumps) mentioned in the literature are actually a single continuous and tortuous crack when observed in three dimension (3D). Contrary to 2D measurements made at the surface which suggest non-uniform crack growth rates, 3D measurements of the crack length led to a much more accurate measurement of crack growth rates.

  18. In situ investigation of high humidity stress corrosion cracking of 7075 aluminum alloy by three-dimensional (3D) X-ray synchrotron tomography

    DOE PAGES

    Singh, S. S.; Williams, J. J.; Lin, M. F.; ...

    2014-05-14

    In situ X-ray synchrotron tomography was used to investigate the stress corrosion cracking behavior of under-aged Al–Zn–Mg–Cu alloy in moisture. The discontinuous surface cracks (crack jumps) mentioned in the literature are actually a single continuous and tortuous crack when observed in three dimension (3D). Contrary to 2D measurements made at the surface which suggest non-uniform crack growth rates, 3D measurements of the crack length led to a much more accurate measurement of crack growth rates.

  19. In vivo mouse myocardial (31)P MRS using three-dimensional image-selected in vivo spectroscopy (3D ISIS): technical considerations and biochemical validations.

    PubMed

    Bakermans, Adrianus J; Abdurrachim, Desiree; van Nierop, Bastiaan J; Koeman, Anneke; van der Kroon, Inge; Baartscheer, Antonius; Schumacher, Cees A; Strijkers, Gustav J; Houten, Sander M; Zuurbier, Coert J; Nicolay, Klaas; Prompers, Jeanine J

    2015-10-01

    (31)P MRS provides a unique non-invasive window into myocardial energy homeostasis. Mouse models of cardiac disease are widely used in preclinical studies, but the application of (31)P MRS in the in vivo mouse heart has been limited. The small-sized, fast-beating mouse heart imposes challenges regarding localized signal acquisition devoid of contamination with signal originating from surrounding tissues. Here, we report the implementation and validation of three-dimensional image-selected in vivo spectroscopy (3D ISIS) for localized (31)P MRS of the in vivo mouse heart at 9.4 T. Cardiac (31)P MR spectra were acquired in vivo in healthy mice (n = 9) and in transverse aortic constricted (TAC) mice (n = 8) using respiratory-gated, cardiac-triggered 3D ISIS. Localization and potential signal contamination were assessed with (31)P MRS experiments in the anterior myocardial wall, liver, skeletal muscle and blood. For healthy hearts, results were validated against ex vivo biochemical assays. Effects of isoflurane anesthesia were assessed by measuring in vivo hemodynamics and blood gases. The myocardial energy status, assessed via the phosphocreatine (PCr) to adenosine 5'-triphosphate (ATP) ratio, was approximately 25% lower in TAC mice compared with controls (0.76 ± 0.13 versus 1.00 ± 0.15; P < 0.01). Localization with one-dimensional (1D) ISIS resulted in two-fold higher PCr/ATP ratios than measured with 3D ISIS, because of the high PCr levels of chest skeletal muscle that contaminate the 1D ISIS measurements. Ex vivo determinations of the myocardial PCr/ATP ratio (0.94 ± 0.24; n = 8) confirmed the in vivo observations in control mice. Heart rate (497 ± 76 beats/min), mean arterial pressure (90 ± 3.3 mmHg) and blood oxygen saturation (96.2 ± 0.6%) during the experimental conditions of in vivo (31)P MRS were within the normal physiological range. Our results show that respiratory-gated, cardiac-triggered 3D ISIS allows for non-invasive assessments of in vivo

  20. Development of a Three-Dimensional (3D) Printed Biodegradable Cage to Convert Morselized Corticocancellous Bone Chips into a Structured Cortical Bone Graft

    PubMed Central

    Chou, Ying-Chao; Lee, Demei; Chang, Tzu-Min; Hsu, Yung-Heng; Yu, Yi-Hsun; Liu, Shih-Jung; Ueng, Steve Wen-Neng

    2016-01-01

    This study aimed to develop a new biodegradable polymeric cage to convert corticocancellous bone chips into a structured strut graft for treating segmental bone defects. A total of 24 adult New Zealand white rabbits underwent a left femoral segmental bone defect creation. Twelve rabbits in group A underwent three-dimensional (3D) printed cage insertion, corticocancellous chips implantation, and Kirschner-wire (K-wire) fixation, while the other 12 rabbits in group B received bone chips implantation and K-wire fixation only. All rabbits received a one-week activity assessment and the initial image study at postoperative 1 week. The final image study was repeated at postoperative 12 or 24 weeks before the rabbit scarification procedure on schedule. After the animals were sacrificed, both femurs of all the rabbits were prepared for leg length ratios and 3-point bending tests. The rabbits in group A showed an increase of activities during the first week postoperatively and decreased anterior cortical disruptions in the postoperative image assessments. Additionally, higher leg length ratios and 3-point bending strengths demonstrated improved final bony ingrowths within the bone defects for rabbits in group A. In conclusion, through this bone graft converting technique, orthopedic surgeons can treat segmental bone defects by using bone chips but with imitate characters of structured cortical bone graft. PMID:27104525

  1. Numerical Analysis of Three-Dimensional Cervical Behaviors in Posterior-Oblique Car Collisions Using 3-D Human Whole Body Finite Element Model

    NASA Astrophysics Data System (ADS)

    Kang, Yu-Bong; Jung, Duk-Young; Tanaka, Masatoshi; Yoshino, Nobuyuki; Tsutsumi, Sadami; Ikeuchi, Ken

    Whiplash injuries are most common disorders in rear-end car accidents, while the injury mechanism is yet unknown. Many numerical and experimental approaches have conducted to investigate the cervical behaviors with solely two-dimensional analyses in the sagittal plane. In real accidents, however, as impacts may affect several directions, the cervical behaviors should be evaluated three-dimensionally. Therefore, we evaluated the cervical behaviors under assumption of the posterior-oblique impacts depending on the impact angles with 3-D FE analysis. In addition, we analyzed the stresses occurred in the facet joints considering the relationship with a whiplash disorders. The cervical behaviors showed complex motion combined with axial torsion and lateral bending. The bending angle peaked in the impact at the angle of 15°, and the peak compressive and shear stress on the facet cartilage at C6-C7 increased by 11% and 14%. In the impact at the angle of 30°, the torsion angle peaked at C2-C3, the peak shear stress in the facet cartilage increased by 27%. It showed that the torsion and lateral bending affected the cervical behaviors, and caused the increase of peak stresses on the soft tissues. It is assumed as one of important causes of whiplash injury.

  2. Patient-tailored plate for bone fixation and accurate 3D positioning in corrective osteotomy.

    PubMed

    Dobbe, J G G; Vroemen, J C; Strackee, S D; Streekstra, G J

    2013-02-01

    A bone fracture may lead to malunion of bone segments, which gives discomfort to the patient and may lead to chronic pain, reduced function and finally to early osteoarthritis. Corrective osteotomy is a treatment option to realign the bone segments. In this procedure, the surgeon tries to improve alignment by cutting the bone at, or near, the fracture location and fixates the bone segments in an improved position, using a plate and screws. Three-dimensional positioning is very complex and difficult to plan, perform and evaluate using standard 2D fluoroscopy imaging. This study introduces a new technique that uses preoperative 3D imaging to plan positioning and design a patient-tailored fixation plate that only fits in one way and realigns the bone segments as planned. The method is evaluated using artificial bones and renders realignment highly accurate and very reproducible (d(err) < 1.2 ± 0.8 mm and φ(err) < 1.8° ± 2.1°). Application of a patient-tailored plate is expected to be of great value for future corrective osteotomy surgeries.

  3. 3-D technology used to accurately understand equine ileocolonic aganglionosis.

    PubMed

    Muniz, Eliane; Lobo Ladd, Aliny A B; Lobo Ladd, Fernando V; da Silva, Andrea A P; Kmit, Fernanda V; Borges, Alexandre S; Teixeira, Raffaella; da Mota, Lígia S L S; Belli, Carla B; de Zoppa, André L V; da Silva, Luis C L C; de Melo, Mariana P; Coppi, Antonio A

    2013-01-01

    Ileocolonic aganglionosis (ICA) is the congenital and hereditary absence of neurons that constitute the enteric nervous system and has been described in various species including humans - Hirschsprung's disease - and horses - overo lethal white syndrome (OLWS). Hirschsprung's disease affects circa 1 in 5,000 live births. At best, this disease means an inability to absorb nutrients from food (humans). At worse, in horses, it always means death. Despite our general understanding of the functional mechanisms underlying ICA, there is a paucity of reliable quantitative information about the structure of myenteric and submucosal neurons in healthy horses and there are no studies on horses with ICA. In light of these uncertainties, we have used design-based stereology to describe the 3-D structure - total number and true size - of myenteric and submucosal neurons in the ileum of ICA horses. Our study has shown that ICA affects all submucosal neurons and 99% of myenteric neurons. The remaining myenteric neurons (0.56%) atrophy immensely, i.e. 63.8%. We believe this study forms the basis for further research, assessing which subpopulation of myenteric neurons are affected by ileocolonic aganglionosis, and we would like to propose a new nomenclature to distinguish between a complete absence of neurons - aganglionosis - and a weaker form of the disease which we suggest naming 'hypoganglionosis'. Our results are a step forward in understanding this disease structurally.

  4. Three-dimensional quantitative structure-activity relationship (3D QSAR) and pharmacophore elucidation of tetrahydropyran derivatives as serotonin and norepinephrine transporter inhibitors

    NASA Astrophysics Data System (ADS)

    Kharkar, Prashant S.; Reith, Maarten E. A.; Dutta, Aloke K.

    2008-01-01

    Three-dimensional quantitative structure-activity relationship (3D QSAR) using comparative molecular field analysis (CoMFA) was performed on a series of substituted tetrahydropyran (THP) derivatives possessing serotonin (SERT) and norepinephrine (NET) transporter inhibitory activities. The study aimed to rationalize the potency of these inhibitors for SERT and NET as well as the observed selectivity differences for NET over SERT. The dataset consisted of 29 molecules, of which 23 molecules were used as the training set for deriving CoMFA models for SERT and NET uptake inhibitory activities. Superimpositions were performed using atom-based fitting and 3-point pharmacophore-based alignment. Two charge calculation methods, Gasteiger-Hückel and semiempirical PM3, were tried. Both alignment methods were analyzed in terms of their predictive abilities and produced comparable results with high internal and external predictivities. The models obtained using the 3-point pharmacophore-based alignment outperformed the models with atom-based fitting in terms of relevant statistics and interpretability of the generated contour maps. Steric fields dominated electrostatic fields in terms of contribution. The selectivity analysis (NET over SERT), though yielded models with good internal predictivity, showed very poor external test set predictions. The analysis was repeated with 24 molecules after systematically excluding so-called outliers (5 out of 29) from the model derivation process. The resulting CoMFA model using the atom-based fitting exhibited good statistics and was able to explain most of the selectivity (NET over SERT)-discriminating factors. The presence of -OH substituent on the THP ring was found to be one of the most important factors governing the NET selectivity over SERT. Thus, a 4-point NET-selective pharmacophore, after introducing this newly found H-bond donor/acceptor feature in addition to the initial 3-point pharmacophore, was proposed.

  5. New three-dimensional head-mounted display system, TMDU-S-3D system, for minimally invasive surgery application: procedures for gasless single-port radical nephrectomy.

    PubMed

    Kihara, Kazunori; Fujii, Yasuhisa; Masuda, Hitoshi; Saito, Kazutaka; Koga, Fumitaka; Matsuoka, Yoh; Numao, Noboru; Kojima, Kazuyuki

    2012-09-01

    We present an application of a new three-dimensional head-mounted display system that combines a high-definition three-dimensional organic electroluminescent head-mounted display with a high-definition three-dimensional endoscope to minimally invasive surgery, using gasless single-port radical nephrectomy procedures as a model. This system presents the surgeon with a higher quality of magnified three-dimensional imagery in front of the eyes regardless of head position, and simultaneously allows direct vision by moving the angle of sight downward. It is also significantly less expensive than the current robotic surgery system. While carrying out gasless single-port radical nephrectomy, the system provided the surgeon with excellent three-dimensional imagery of the operative field, direct vision of the outside and inside of the patient, and depth perception and tactile feedback through the devices. All four nephrectomies were safely completed within the operative time, blood loss was within usual limits and there were no complications. The display was light enough to comfortably be worn for a long operative time. Our experiences show that the three-dimensional head-mounted display system might facilitate maneuverability and safety in minimally invasive procedures, without prohibitive cost, and thus might mitigate the drawbacks of other three-dimensional vision systems. Because of the potential benefits that this system offers, it deserves further refinements of its role in various minimally invasive surgeries.

  6. A Primer for the Linkage Between Unstructured Water Quality Model CE-QUAL-ICM and Structured Three-Dimensional Hydrodynamic Model CH3D-WES

    DTIC Science & Technology

    2007-10-01

    2. If Q=3, two numbers show the k koordinates of boxes beneath and on the face. m . SFC BOX #: number of surface boxes n. NVF: number of faces...T. Cole. 1993. Three-dimensional eutrophication model of Chesapeake Bay. J. Environ. Eng. 119:1006-1025. Cerco, C. F., and M . Noel. 2004. The 2002...F., M . Noel. and S.-C. Kim. 2006. Three-dimensional management model for Lake Washington, Part II: Eutrophication modeling and skill assessment. Lake

  7. Simulation and experimental studies of three-dimensional (3D) image reconstruction from insufficient sampling data based on compressed-sensing theory for potential applications to dental cone-beam CT

    NASA Astrophysics Data System (ADS)

    Je, U. K.; Lee, M. S.; Cho, H. S.; Hong, D. K.; Park, Y. O.; Park, C. K.; Cho, H. M.; Choi, S. I.; Woo, T. H.

    2015-06-01

    In practical applications of three-dimensional (3D) tomographic imaging, there are often challenges for image reconstruction from insufficient sampling data. In computed tomography (CT), for example, image reconstruction from sparse views and/or limited-angle (<360°) views would enable fast scanning with reduced imaging doses to the patient. In this study, we investigated and implemented a reconstruction algorithm based on the compressed-sensing (CS) theory, which exploits the sparseness of the gradient image with substantially high accuracy, for potential applications to low-dose, high-accurate dental cone-beam CT (CBCT). We performed systematic simulation works to investigate the image characteristics and also performed experimental works by applying the algorithm to a commercially-available dental CBCT system to demonstrate its effectiveness for image reconstruction in insufficient sampling problems. We successfully reconstructed CBCT images of superior accuracy from insufficient sampling data and evaluated the reconstruction quality quantitatively. Both simulation and experimental demonstrations of the CS-based reconstruction from insufficient data indicate that the CS-based algorithm can be applied directly to current dental CBCT systems for reducing the imaging doses and further improving the image quality.

  8. Accurate positioning for head and neck cancer patients using 2D and 3D image guidance

    PubMed Central

    Kang, Hyejoo; Lovelock, Dale M.; Yorke, Ellen D.; Kriminiski, Sergey; Lee, Nancy; Amols, Howard I.

    2011-01-01

    Our goal is to determine an optimized image-guided setup by comparing setup errors determined by two-dimensional (2D) and three-dimensional (3D) image guidance for head and neck cancer (HNC) patients immobilized by customized thermoplastic masks. Nine patients received weekly imaging sessions, for a total of 54, throughout treatment. Patients were first set up by matching lasers to surface marks (initial) and then translationally corrected using manual registration of orthogonal kilovoltage (kV) radiographs with DRRs (2D-2D) on bony anatomy. A kV cone beam CT (kVCBCT) was acquired and manually registered to the simulation CT using only translations (3D-3D) on the same bony anatomy to determine further translational corrections. After treatment, a second set of kVCBCT was acquired to assess intrafractional motion. Averaged over all sessions, 2D-2D registration led to translational corrections from initial setup of 3.5 ± 2.2 (range 0–8) mm. The addition of 3D-3D registration resulted in only small incremental adjustment (0.8 ± 1.5 mm). We retrospectively calculated patient setup rotation errors using an automatic rigid-body algorithm with 6 degrees of freedom (DoF) on regions of interest (ROI) of in-field bony anatomy (mainly the C2 vertebral body). Small rotations were determined for most of the imaging sessions; however, occasionally rotations > 3° were observed. The calculated intrafractional motion with automatic registration was < 3.5 mm for eight patients, and < 2° for all patients. We conclude that daily manual 2D-2D registration on radiographs reduces positioning errors for mask-immobilized HNC patients in most cases, and is easily implemented. 3D-3D registration adds little improvement over 2D-2D registration without correcting rotational errors. We also conclude that thermoplastic masks are effective for patient immobilization. PMID:21330971

  9. New potent and selective cytochrome P450 2B6 (CYP2B6) inhibitors based on three-dimensional quantitative structure-activity relationship (3D-QSAR) analysis

    PubMed Central

    Korhonen, L E; Turpeinen, M; Rahnasto, M; Wittekindt, C; Poso, A; Pelkonen, O; Raunio, H; Juvonen, R O

    2007-01-01

    Background and purpose: The cytochrome P450 2B6 (CYP2B6) enzyme metabolises a number of clinically important drugs. Drug-drug interactions resulting from inhibition or induction of CYP2B6 activity may cause serious adverse effects. The aims of this study were to construct a three-dimensional structure-activity relationship (3D-QSAR) model of the CYP2B6 protein and to identify novel potent and selective inhibitors of CYP2B6 for in vitro research purposes. Experimental approach: The inhibition potencies (IC50 values) of structurally diverse chemicals were determined with recombinant human CYP2B6 enzyme. Two successive models were constructed using Comparative Molecular Field Analysis (CoMFA). Key results: Three compounds proved to be very potent and selective competitive inhibitors of CYP2B6 in vitro (IC50<1 μM): 4-(4-chlorobenzyl)pyridine (CBP), 4-(4-nitrobenzyl)pyridine (NBP), and 4-benzylpyridine (BP). A complete inhibition of CYP2B6 activity was achieved with 0.1 μM CBP, whereas other CYP-related activities were not affected. Forty-one compounds were selected for further testing and construction of the final CoMFA model. The created CoMFA model was of high quality and predicted accurately the inhibition potency of a test set (n=7) of structurally diverse compounds. Conclusions and implications: Two CoMFA models were created which revealed the key molecular characteristics of inhibitors of the CYP2B6 enzyme. The final model accurately predicted the inhibitory potencies of several structurally unrelated compounds. CBP, BP and NBP were identified as novel potent and selective inhibitors of CYP2B6 and CBP especially is a suitable inhibitor for in vitro screening studies. PMID:17325652

  10. Prognostic breast cancer signature identified from 3D culture model accurately predicts clinical outcome across independent datasets

    SciTech Connect

    Martin, Katherine J.; Patrick, Denis R.; Bissell, Mina J.; Fournier, Marcia V.

    2008-10-20

    One of the major tenets in breast cancer research is that early detection is vital for patient survival by increasing treatment options. To that end, we have previously used a novel unsupervised approach to identify a set of genes whose expression predicts prognosis of breast cancer patients. The predictive genes were selected in a well-defined three dimensional (3D) cell culture model of non-malignant human mammary epithelial cell morphogenesis as down-regulated during breast epithelial cell acinar formation and cell cycle arrest. Here we examine the ability of this gene signature (3D-signature) to predict prognosis in three independent breast cancer microarray datasets having 295, 286, and 118 samples, respectively. Our results show that the 3D-signature accurately predicts prognosis in three unrelated patient datasets. At 10 years, the probability of positive outcome was 52, 51, and 47 percent in the group with a poor-prognosis signature and 91, 75, and 71 percent in the group with a good-prognosis signature for the three datasets, respectively (Kaplan-Meier survival analysis, p<0.05). Hazard ratios for poor outcome were 5.5 (95% CI 3.0 to 12.2, p<0.0001), 2.4 (95% CI 1.6 to 3.6, p<0.0001) and 1.9 (95% CI 1.1 to 3.2, p = 0.016) and remained significant for the two larger datasets when corrected for estrogen receptor (ER) status. Hence the 3D-signature accurately predicts breast cancer outcome in both ER-positive and ER-negative tumors, though individual genes differed in their prognostic ability in the two subtypes. Genes that were prognostic in ER+ patients are AURKA, CEP55, RRM2, EPHA2, FGFBP1, and VRK1, while genes prognostic in ER patients include ACTB, FOXM1 and SERPINE2 (Kaplan-Meier p<0.05). Multivariable Cox regression analysis in the largest dataset showed that the 3D-signature was a strong independent factor in predicting breast cancer outcome. The 3D-signature accurately predicts breast cancer outcome across multiple datasets and holds prognostic

  11. Rapid 3D printing of anatomically accurate and mechanically heterogeneous aortic valve hydrogel scaffolds.

    PubMed

    Hockaday, L A; Kang, K H; Colangelo, N W; Cheung, P Y C; Duan, B; Malone, E; Wu, J; Girardi, L N; Bonassar, L J; Lipson, H; Chu, C C; Butcher, J T

    2012-09-01

    The aortic valve exhibits complex three-dimensional (3D) anatomy and heterogeneity essential for the long-term efficient biomechanical function. These are, however, challenging to mimic in de novo engineered living tissue valve strategies. We present a novel simultaneous 3D printing/photocrosslinking technique for rapidly engineering complex, heterogeneous aortic valve scaffolds. Native anatomic and axisymmetric aortic valve geometries (root wall and tri-leaflets) with 12-22 mm inner diameters (ID) were 3D printed with poly-ethylene glycol-diacrylate (PEG-DA) hydrogels (700 or 8000 MW) supplemented with alginate. 3D printing geometric accuracy was quantified and compared using Micro-CT. Porcine aortic valve interstitial cells (PAVIC) seeded scaffolds were cultured for up to 21 days. Results showed that blended PEG-DA scaffolds could achieve over tenfold range in elastic modulus (5.3±0.9 to 74.6±1.5 kPa). 3D printing times for valve conduits with mechanically contrasting hydrogels were optimized to 14 to 45 min, increasing linearly with conduit diameter. Larger printed valves had greater shape fidelity (93.3±2.6, 85.1±2.0 and 73.3±5.2% for 22, 17 and 12 mm ID porcine valves; 89.1±4.0, 84.1±5.6 and 66.6±5.2% for simplified valves). PAVIC seeded scaffolds maintained near 100% viability over 21 days. These results demonstrate that 3D hydrogel printing with controlled photocrosslinking can rapidly fabricate anatomical heterogeneous valve conduits that support cell engraftment.

  12. Time-accurate anisotropic mesh adaptation for three-dimensional time-dependent problems with body-fitted moving geometries

    NASA Astrophysics Data System (ADS)

    Barral, N.; Olivier, G.; Alauzet, F.

    2017-02-01

    Anisotropic metric-based mesh adaptation has proved its efficiency to reduce the CPU time of steady and unsteady simulations while improving their accuracy. However, its extension to time-dependent problems with body-fitted moving geometries is far from straightforward. This paper establishes a well-founded framework for multiscale mesh adaptation of unsteady problems with moving boundaries. This framework is based on a novel space-time analysis of the interpolation error, within the continuous mesh theory. An optimal metric field, called ALE metric field, is derived, which takes into account the movement of the mesh during the adaptation. Based on this analysis, the global fixed-point adaptation algorithm for time-dependent simulations is extended to moving boundary problems, within the range of body-fitted moving meshes and ALE simulations. Finally, three dimensional adaptive simulations with moving boundaries are presented to validate the proposed approach.

  13. Accurate compressed look up table method for CGH in 3D holographic display.

    PubMed

    Gao, Chuan; Liu, Juan; Li, Xin; Xue, Gaolei; Jia, Jia; Wang, Yongtian

    2015-12-28

    Computer generated hologram (CGH) should be obtained with high accuracy and high speed in 3D holographic display, and most researches focus on the high speed. In this paper, a simple and effective computation method for CGH is proposed based on Fresnel diffraction theory and look up table. Numerical simulations and optical experiments are performed to demonstrate its feasibility. The proposed method can obtain more accurate reconstructed images with lower memory usage compared with split look up table method and compressed look up table method without sacrificing the computational speed in holograms generation, so it is called accurate compressed look up table method (AC-LUT). It is believed that AC-LUT method is an effective method to calculate the CGH of 3D objects for real-time 3D holographic display where the huge information data is required, and it could provide fast and accurate digital transmission in various dynamic optical fields in the future.

  14. Three-Dimensional Mapping of Soil Chemical Characteristics at Micrometric Scale by Combining 2D SEM-EDX Data and 3D X-Ray CT Images

    PubMed Central

    Hapca, Simona; Baveye, Philippe C.; Wilson, Clare; Lark, Richard Murray; Otten, Wilfred

    2015-01-01

    There is currently a significant need to improve our understanding of the factors that control a number of critical soil processes by integrating physical, chemical and biological measurements on soils at microscopic scales to help produce 3D maps of the related properties. Because of technological limitations, most chemical and biological measurements can be carried out only on exposed soil surfaces or 2-dimensional cuts through soil samples. Methods need to be developed to produce 3D maps of soil properties based on spatial sequences of 2D maps. In this general context, the objective of the research described here was to develop a method to generate 3D maps of soil chemical properties at the microscale by combining 2D SEM-EDX data with 3D X-ray computed tomography images. A statistical approach using the regression tree method and ordinary kriging applied to the residuals was developed and applied to predict the 3D spatial distribution of carbon, silicon, iron, and oxygen at the microscale. The spatial correlation between the X-ray grayscale intensities and the chemical maps made it possible to use a regression-tree model as an initial step to predict the 3D chemical composition. For chemical elements, e.g., iron, that are sparsely distributed in a soil sample, the regression-tree model provides a good prediction, explaining as much as 90% of the variability in some of the data. However, for chemical elements that are more homogenously distributed, such as carbon, silicon, or oxygen, the additional kriging of the regression tree residuals improved significantly the prediction with an increase in the R2 value from 0.221 to 0.324 for carbon, 0.312 to 0.423 for silicon, and 0.218 to 0.374 for oxygen, respectively. The present research develops for the first time an integrated experimental and theoretical framework, which combines geostatistical methods with imaging techniques to unveil the 3-D chemical structure of soil at very fine scales. The methodology presented

  15. Three-Dimensional Mapping of Soil Chemical Characteristics at Micrometric Scale by Combining 2D SEM-EDX Data and 3D X-Ray CT Images.

    PubMed

    Hapca, Simona; Baveye, Philippe C; Wilson, Clare; Lark, Richard Murray; Otten, Wilfred

    2015-01-01

    There is currently a significant need to improve our understanding of the factors that control a number of critical soil processes by integrating physical, chemical and biological measurements on soils at microscopic scales to help produce 3D maps of the related properties. Because of technological limitations, most chemical and biological measurements can be carried out only on exposed soil surfaces or 2-dimensional cuts through soil samples. Methods need to be developed to produce 3D maps of soil properties based on spatial sequences of 2D maps. In this general context, the objective of the research described here was to develop a method to generate 3D maps of soil chemical properties at the microscale by combining 2D SEM-EDX data with 3D X-ray computed tomography images. A statistical approach using the regression tree method and ordinary kriging applied to the residuals was developed and applied to predict the 3D spatial distribution of carbon, silicon, iron, and oxygen at the microscale. The spatial correlation between the X-ray grayscale intensities and the chemical maps made it possible to use a regression-tree model as an initial step to predict the 3D chemical composition. For chemical elements, e.g., iron, that are sparsely distributed in a soil sample, the regression-tree model provides a good prediction, explaining as much as 90% of the variability in some of the data. However, for chemical elements that are more homogenously distributed, such as carbon, silicon, or oxygen, the additional kriging of the regression tree residuals improved significantly the prediction with an increase in the R2 value from 0.221 to 0.324 for carbon, 0.312 to 0.423 for silicon, and 0.218 to 0.374 for oxygen, respectively. The present research develops for the first time an integrated experimental and theoretical framework, which combines geostatistical methods with imaging techniques to unveil the 3-D chemical structure of soil at very fine scales. The methodology presented

  16. Sub-micrometre accurate free-form optics by three-dimensional printing on single-mode fibres.

    PubMed

    Gissibl, Timo; Thiele, Simon; Herkommer, Alois; Giessen, Harald

    2016-06-24

    Micro-optics are widely used in numerous applications, such as beam shaping, collimation, focusing and imaging. We use femtosecond 3D printing to manufacture free-form micro-optical elements. Our method gives sub-micrometre accuracy so that direct manufacturing even on single-mode fibres is possible. We demonstrate the potential of our method by writing different collimation optics, toric lenses, free-form surfaces with polynomials of up to 10th order for intensity beam shaping, as well as chiral photonic crystals for circular polarization filtering, all aligned onto the core of the single-mode fibres. We determine the accuracy of our optics by analysing the output patterns as well as interferometrically characterizing the surfaces. We find excellent agreement with numerical calculations. 3D printing of microoptics can achieve sufficient performance that will allow for rapid prototyping and production of beam-shaping and imaging devices.

  17. Sub-micrometre accurate free-form optics by three-dimensional printing on single-mode fibres

    PubMed Central

    Gissibl, Timo; Thiele, Simon; Herkommer, Alois; Giessen, Harald

    2016-01-01

    Micro-optics are widely used in numerous applications, such as beam shaping, collimation, focusing and imaging. We use femtosecond 3D printing to manufacture free-form micro-optical elements. Our method gives sub-micrometre accuracy so that direct manufacturing even on single-mode fibres is possible. We demonstrate the potential of our method by writing different collimation optics, toric lenses, free-form surfaces with polynomials of up to 10th order for intensity beam shaping, as well as chiral photonic crystals for circular polarization filtering, all aligned onto the core of the single-mode fibres. We determine the accuracy of our optics by analysing the output patterns as well as interferometrically characterizing the surfaces. We find excellent agreement with numerical calculations. 3D printing of microoptics can achieve sufficient performance that will allow for rapid prototyping and production of beam-shaping and imaging devices. PMID:27339700

  18. Enabling accurate gate profile control with inline 3D-AFM

    NASA Astrophysics Data System (ADS)

    Bao, Tianming; Lopez, Andrew; Dawson, Dean

    2009-05-01

    The logic and memory semiconductor device technology strives to follow the aggressive ITRS roadmap. The ITRS calls for increased 3D metrology to meet the demand for tighter process control at 45nm and 32nm nodes. In particular, gate engineering has advanced to a level where conventional metrology by CD-SEM and optical scatterometry (OCD) faces fundamental limitations without involvement of 3D atomic force microscope (3D-AFM or CD-AFM). This paper reports recent progress in 3D-AFM to address the metrology need to control gate dimension in MOSFET transistor formation. 3D-AFM metrology measures the gate electrode at post-etch with the lowest measurement uncertainty for critical gate geometry, including linewidth, sidewall profile, sidewall angle (SWA), line width roughness (LWR), and line edge roughness (LER). 3D-AFM enables accurate gate profile control in three types of metrology applications: reference metrology to validate CD-SEM and OCD, inline depth or 3D monitoring, or replacing TEM for 3D characterization for engineering analysis.

  19. Accurate spike estimation from noisy calcium signals for ultrafast three-dimensional imaging of large neuronal populations in vivo

    PubMed Central

    Deneux, Thomas; Kaszas, Attila; Szalay, Gergely; Katona, Gergely; Lakner, Tamás; Grinvald, Amiram; Rózsa, Balázs; Vanzetta, Ivo

    2016-01-01

    Extracting neuronal spiking activity from large-scale two-photon recordings remains challenging, especially in mammals in vivo, where large noises often contaminate the signals. We propose a method, MLspike, which returns the most likely spike train underlying the measured calcium fluorescence. It relies on a physiological model including baseline fluctuations and distinct nonlinearities for synthetic and genetically encoded indicators. Model parameters can be either provided by the user or estimated from the data themselves. MLspike is computationally efficient thanks to its original discretization of probability representations; moreover, it can also return spike probabilities or samples. Benchmarked on extensive simulations and real data from seven different preparations, it outperformed state-of-the-art algorithms. Combined with the finding obtained from systematic data investigation (noise level, spiking rate and so on) that photonic noise is not necessarily the main limiting factor, our method allows spike extraction from large-scale recordings, as demonstrated on acousto-optical three-dimensional recordings of over 1,000 neurons in vivo. PMID:27432255

  20. JAC3D -- A three-dimensional finite element computer program for the nonlinear quasi-static response of solids with the conjugate gradient method; Yucca Mountain Site Characterization Project

    SciTech Connect

    Biffle, J.H.

    1993-02-01

    JAC3D is a three-dimensional finite element program designed to solve quasi-static nonlinear mechanics problems. A set of continuum equations describes the nonlinear mechanics involving large rotation and strain. A nonlinear conjugate gradient method is used to solve the equation. The method is implemented in a three-dimensional setting with various methods for accelerating convergence. Sliding interface logic is also implemented. An eight-node Lagrangian uniform strain element is used with hourglass stiffness to control the zero-energy modes. This report documents the elastic and isothermal elastic-plastic material model. Other material models, documented elsewhere, are also available. The program is vectorized for efficient performance on Cray computers. Sample problems described are the bending of a thin beam, the rotation of a unit cube, and the pressurization and thermal loading of a hollow sphere.

  1. SU-E-T-490: Independent Three-Dimensional (3D) Dose Verification of VMAT/SBRT Using EPID and Cloud Computing

    SciTech Connect

    Ding, A; Han, B; Bush, K; Wang, L; Xing, L

    2015-06-15

    Purpose: Dosimetric verification of VMAT/SBRT is currently performed on one or two planes in a phantom with either film or array detectors. A robust and easy-to-use 3D dosimetric tool has been sought since the advent of conformal radiation therapy. Here we present such a strategy for independent 3D VMAT/SBRT plan verification system by a combined use of EPID and cloud-based Monte Carlo (MC) dose calculation. Methods: The 3D dosimetric verification proceeds in two steps. First, the plan was delivered with a high resolution portable EPID mounted on the gantry, and the EPID-captured gantry-angle-resolved VMAT/SBRT field images were converted into fluence by using the EPID pixel response function derived from MC simulations. The fluence was resampled and used as the input for an in-house developed Amazon cloud-based MC software to reconstruct the 3D dose distribution. The accuracy of the developed 3D dosimetric tool was assessed using a Delta4 phantom with various field sizes (square, circular, rectangular, and irregular MLC fields) and different patient cases. The method was applied to validate VMAT/SBRT plans using WFF and FFF photon beams (Varian TrueBeam STX). Results: It was found that the proposed method yielded results consistent with the Delta4 measurements. For points on the two detector planes, a good agreement within 1.5% were found for all the testing fields. Patient VMAT/SBRT plan studies revealed similar level of accuracy: an average γ-index passing rate of 99.2± 0.6% (3mm/3%), 97.4± 2.4% (2mm/2%), and 72.6± 8.4 % ( 1mm/1%). Conclusion: A valuable 3D dosimetric verification strategy has been developed for VMAT/SBRT plan validation. The technique provides a viable solution for a number of intractable dosimetry problems, such as small fields and plans with high dose gradient.

  2. Hybrid 3-D rocket trajectory program. Part 1: Formulation and analysis. Part 2: Computer programming and user's instruction. [computerized simulation using three dimensional motion analysis

    NASA Technical Reports Server (NTRS)

    Huang, L. C. P.; Cook, R. A.

    1973-01-01

    Models utilizing various sub-sets of the six degrees of freedom are used in trajectory simulation. A 3-D model with only linear degrees of freedom is especially attractive, since the coefficients for the angular degrees of freedom are the most difficult to determine and the angular equations are the most time consuming for the computer to evaluate. A computer program is developed that uses three separate subsections to predict trajectories. A launch rail subsection is used until the rocket has left its launcher. The program then switches to a special 3-D section which computes motions in two linear and one angular degrees of freedom. When the rocket trims out, the program switches to the standard, three linear degrees of freedom model.

  3. Multiscale microstructural characterization of Sn-rich alloys by three dimensional (3D) X-ray synchrotron tomography and focused ion beam (FIB) tomography

    SciTech Connect

    Yazzie, K.E.; Williams, J.J.; Phillips, N.C.; De Carlo, F.; Chawla, N.

    2012-08-15

    Sn-rich (Pb-free) alloys serve as electrical and mechanical interconnects in electronic packaging. It is critical to quantify the microstructures of Sn-rich alloys to obtain a fundamental understanding of their properties. In this work, the intermetallic precipitates in Sn-3.5Ag and Sn-0.7Cu, and globular lamellae in Sn-37Pb solder joints were visualized and quantified using 3D X-ray synchrotron tomography and focused ion beam (FIB) tomography. 3D reconstructions were analyzed to extract statistics on particle size and spatial distribution. In the Sn-Pb alloy the interconnectivity of Sn-rich and Pb-rich constituents was quantified. It will be shown that multiscale characterization using 3D X-ray and FIB tomography enabled the characterization of the complex morphology, distribution, and statistics of precipitates and contiguous phases over a range of length scales. - Highlights: Black-Right-Pointing-Pointer Multiscale characterization by X-ray synchrotron and focused ion beam tomography. Black-Right-Pointing-Pointer Characterized microstructural features in several Sn-based alloys. Black-Right-Pointing-Pointer Quantified size, fraction, and clustering of microstructural features.

  4. Development of a lab-scale, high-resolution, tube-generated X-ray computed-tomography system for three-dimensional (3D) materials characterization

    SciTech Connect

    Mertens, J.C.E. Williams, J.J. Chawla, Nikhilesh

    2014-06-01

    The design and construction of a modular high resolution X-ray computed tomography (XCT) system is highlighted in this paper. The design approach is detailed for meeting a specified set of instrument performance goals tailored towards experimental versatility and high resolution imaging. The XCT tool is unique in the detector and X-ray source design configuration, enabling control in the balance between detection efficiency and spatial resolution. The system package is also unique: The sample manipulation approach implemented enables a wide gamut of in situ experimentation to analyze structure evolution under applied stimulus, by optimizing scan conditions through a high degree of controllability. The component selection and design process is detailed: Incorporated components are specified, custom designs are shared, and the approach for their integration into a fully functional XCT scanner is provided. Custom designs discussed include the dual-target X-ray source cradle which maintains position and trajectory of the beam between the two X-ray target configurations with respect to a scintillator mounting and positioning assembly and the imaging sensor, as well as a novel large-format X-ray detector with enhanced adaptability. The instrument is discussed from an operational point of view, including the details of data acquisition and processing implemented for 3D imaging via micro-CT. The performance of the instrument is demonstrated on a silica-glass particle/hydroxyl-terminated-polybutadiene (HTPB) matrix binder PBX simulant. Post-scan data processing, specifically segmentation of the sample's relevant microstructure from the 3D reconstruction, is provided to demonstrate the utility of the instrument. - Highlights: • Custom built X-ray tomography system for microstructural characterization • Detector design for maximizing polychromatic X-ray detection efficiency • X-ray design offered for maximizing X-ray flux with respect to imaging resolution • Novel lab

  5. Three-Dimensional (3D) Bicontinuous Hierarchically Porous Mn2O3 Single Crystals for High Performance Lithium-Ion Batteries.

    PubMed

    Huang, Shao-Zhuan; Jin, Jun; Cai, Yi; Li, Yu; Deng, Zhao; Zeng, Jun-Yang; Liu, Jing; Wang, Chao; Hasan, Tawfique; Su, Bao-Lian

    2015-10-06

    Bicontinuous hierarchically porous Mn2O3 single crystals (BHP-Mn2O3-SCs) with uniform parallelepiped geometry and tunable sizes have been synthesized and used as anode materials for lithium-ion batteries (LIBs). The monodispersed BHP-Mn2O3-SCs exhibit high specific surface area and three dimensional interconnected bimodal mesoporosity throughout the entire crystal. Such hierarchical interpenetrating porous framework can not only provide a large number of active sites for Li ion insertion, but also good conductivity and short diffusion length for Li ions, leading to a high lithium storage capacity and enhanced rate capability. Furthermore, owing to their specific porosity, these BHP-Mn2O3-SCs as anode materials can accommodate the volume expansion/contraction that occurs with lithium insertion/extraction during discharge/charge processes, resulting in their good cycling performance. Our synthesized BHP-Mn2O3-SCs with a size of ~700 nm display the best electrochemical performance, with a large reversible capacity (845 mA h g(-1) at 100 mA g(-1) after 50 cycles), high coulombic efficiency (>95%), excellent cycling stability and superior rate capability (410 mA h g(-1) at 1 Ag(-1)). These values are among the highest reported for Mn2O3-based bulk solids and nanostructures. Also, electrochemical impedance spectroscopy study demonstrates that the BHP-Mn2O3-SCs are suitable for charge transfer at the electrode/electrolyte interface.

  6. Three-Dimensional (3D) Bicontinuous Hierarchically Porous Mn2O3 Single Crystals for High Performance Lithium-Ion Batteries

    NASA Astrophysics Data System (ADS)

    Huang, Shao-Zhuan; Jin, Jun; Cai, Yi; Li, Yu; Deng, Zhao; Zeng, Jun-Yang; Liu, Jing; Wang, Chao; Hasan, Tawfique; Su, Bao-Lian

    2015-10-01

    Bicontinuous hierarchically porous Mn2O3 single crystals (BHP-Mn2O3-SCs) with uniform parallelepiped geometry and tunable sizes have been synthesized and used as anode materials for lithium-ion batteries (LIBs). The monodispersed BHP-Mn2O3-SCs exhibit high specific surface area and three dimensional interconnected bimodal mesoporosity throughout the entire crystal. Such hierarchical interpenetrating porous framework can not only provide a large number of active sites for Li ion insertion, but also good conductivity and short diffusion length for Li ions, leading to a high lithium storage capacity and enhanced rate capability. Furthermore, owing to their specific porosity, these BHP-Mn2O3-SCs as anode materials can accommodate the volume expansion/contraction that occurs with lithium insertion/extraction during discharge/charge processes, resulting in their good cycling performance. Our synthesized BHP-Mn2O3-SCs with a size of ~700 nm display the best electrochemical performance, with a large reversible capacity (845 mA h g-1 at 100 mA g-1 after 50 cycles), high coulombic efficiency (>95%), excellent cycling stability and superior rate capability (410 mA h g-1 at 1 Ag-1). These values are among the highest reported for Mn2O3-based bulk solids and nanostructures. Also, electrochemical impedance spectroscopy study demonstrates that the BHP-Mn2O3-SCs are suitable for charge transfer at the electrode/electrolyte interface.

  7. Three-dimensional (3D) coseismic deformation map produced by the 2014 South Napa Earthquake estimated and modeled by SAR and GPS data integration

    NASA Astrophysics Data System (ADS)

    Polcari, Marco; Albano, Matteo; Fernández, José; Palano, Mimmo; Samsonov, Sergey; Stramondo, Salvatore; Zerbini, Susanna

    2016-04-01

    In this work we present a 3D map of coseismic displacements due to the 2014 Mw 6.0 South Napa earthquake, California, obtained by integrating displacement information data from SAR Interferometry (InSAR), Multiple Aperture Interferometry (MAI), Pixel Offset Tracking (POT) and GPS data acquired by both permanent stations and campaigns sites. This seismic event produced significant surface deformation along the 3D components causing several damages to vineyards, roads and houses. The remote sensing results, i.e. InSAR, MAI and POT, were obtained from the pair of SAR images provided by the Sentinel-1 satellite, launched on April 3rd, 2014. They were acquired on August 7th and 31st along descending orbits with an incidence angle of about 23°. The GPS dataset includes measurements from 32 stations belonging to the Bay Area Regional Deformation Network (BARDN), 301 continuous stations available from the UNAVCO and the CDDIS archives, and 13 additional campaign sites from Barnhart et al, 2014 [1]. These data constrain the horizontal and vertical displacement components proving to be helpful for the adopted integration method. We exploit the Bayes theory to search for the 3D coseismic displacement components. In particular, for each point, we construct an energy function and solve the problem to find a global minimum. Experimental results are consistent with a strike-slip fault mechanism with an approximately NW-SE fault plane. Indeed, the 3D displacement map shows a strong North-South (NS) component, peaking at about 15 cm, a few kilometers far from the epicenter. The East-West (EW) displacement component reaches its maximum (~10 cm) south of the city of Napa, whereas the vertical one (UP) is smaller, although a subsidence in the order of 8 cm on the east side of the fault can be observed. A source modelling was performed by inverting the estimated displacement components. The best fitting model is given by a ~N330° E-oriented and ~70° dipping fault with a prevailing

  8. IVUSAngio tool: a publicly available software for fast and accurate 3D reconstruction of coronary arteries.

    PubMed

    Doulaverakis, Charalampos; Tsampoulatidis, Ioannis; Antoniadis, Antonios P; Chatzizisis, Yiannis S; Giannopoulos, Andreas; Kompatsiaris, Ioannis; Giannoglou, George D

    2013-11-01

    There is an ongoing research and clinical interest in the development of reliable and easily accessible software for the 3D reconstruction of coronary arteries. In this work, we present the architecture and validation of IVUSAngio Tool, an application which performs fast and accurate 3D reconstruction of the coronary arteries by using intravascular ultrasound (IVUS) and biplane angiography data. The 3D reconstruction is based on the fusion of the detected arterial boundaries in IVUS images with the 3D IVUS catheter path derived from the biplane angiography. The IVUSAngio Tool suite integrates all the intermediate processing and computational steps and provides a user-friendly interface. It also offers additional functionality, such as automatic selection of the end-diastolic IVUS images, semi-automatic and automatic IVUS segmentation, vascular morphometric measurements, graphical visualization of the 3D model and export in a format compatible with other computer-aided design applications. Our software was applied and validated in 31 human coronary arteries yielding quite promising results. Collectively, the use of IVUSAngio Tool significantly reduces the total processing time for 3D coronary reconstruction. IVUSAngio Tool is distributed as free software, publicly available to download and use.

  9. Three-Dimensional Rotation, Twist and Torsion Analyses Using Real-Time 3D Speckle Tracking Imaging: Feasibility, Reproducibility, and Normal Ranges in Pediatric Population

    PubMed Central

    Han, Wei; Gao, Jun; He, Lin; Yang, Yali; Yin, Ping; Xie, Mingxing; Ge, Shuping

    2016-01-01

    Background and Objective The specific aim of this study was to evaluate the feasibility, reproducibility and maturational changes of LV rotation, twist and torsion variables by real-time 3D speckle-tracking echocardiography (RT3DSTE) in children. Methods A prospective study was conducted in 347 consecutive healthy subjects (181 males/156 females, mean age 7.12 ± 5.3 years, and range from birth to 18-years) using RT 3D echocardiography (3DE). The LV rotation, twist and torsion measurements were made off-line using TomTec software. Manual landmark selection and endocardial border editing were performed in 3 planes (apical “2”-, “4”-, and “3”- chamber views) and semi-automated tracking yielded LV rotation, twist and torsion measurements. LV rotation, twist and torsion analysis by RT 3DSTE were feasible in 307 out of 347 subjects (88.5%). Results There was no correlation between rotation or twist and age, height, weight, BSA or heart rate, respectively. However, there was statistically significant, but very modest correlation between LV torsion and age (R2 = 0.036, P< 0.001). The normal ranges were defined for rotation and twist in this cohort, and for torsion for each age group. The intra-observer and inter-observer variabilities for apical and basal rotation, twist and torsion ranged from 7.3% ± 3.8% to 12.3% ± 8.8% and from 8.8% ± 4.6% to 15.7% ± 10.1%, respectively. Conclusions We conclude that analysis of LV rotation, twist and torsion by this new RT3D STE is feasible and reproducible in pediatric population. There is no maturational change in rotation and twist, but torsion decreases with age in this cohort. Further refinement is warranted to validate the utility of this new methodology in more sensitive and quantitative evaluation of congenital and acquired heart diseases in children. PMID:27427968

  10. Developing and Evaluating of Non-Realistic Three-Dimensional (3d-Nr) and Two-Dimensional (2d) Talking-Head Animation Courseware

    ERIC Educational Resources Information Center

    Hamdan, Mohd Najib; Ali, Ahmad Zamzuri Mohamad

    2015-01-01

    The talking-head animation is an instructional animation capable of improving the communication skills through enhancing the pronunciation skills; whereby a word is pronounced correctly and accurately. This had been proven by several researches, which indicate that learning with interactive animation is much more advantageous than conventional…

  11. Basic Research on Three-Dimensional (3D) Electromagnetic (EM) Methods for Imaging the Flow of Organic Fluids in the Subsurface.

    DTIC Science & Technology

    1997-04-30

    Currently there are no systems available which allow for economical and accurate subsurface imaging of remediation sites. In some cases, high...system to address this need. This project has been very successful in showing a promising new direction for high resolution subsurface imaging . Our

  12. GRID2D/3D: A computer program for generating grid systems in complex-shaped two- and three-dimensional spatial domains. Part 2: User's manual and program listing

    NASA Technical Reports Server (NTRS)

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

    1990-01-01

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

  13. Progress Toward an Integration of Process-Structure-Property-Performance Models for "Three-Dimensional (3-D) Printing" of Titanium Alloys

    NASA Astrophysics Data System (ADS)

    Collins, P. C.; Haden, C. V.; Ghamarian, I.; Hayes, B. J.; Ales, T.; Penso, G.; Dixit, V.; Harlow, G.

    2014-07-01

    Electron beam direct manufacturing, synonymously known as electron beam additive manufacturing, along with other additive "3-D printing" manufacturing processes, are receiving widespread attention as a means of producing net-shape (or near-net-shape) components, owing to potential manufacturing benefits. Yet, materials scientists know that differences in manufacturing processes often significantly influence the microstructure of even widely accepted materials and, thus, impact the properties and performance of a material in service. It is important to accelerate the understanding of the processing-structure-property relationship of materials being produced via these novel approaches in a framework that considers the performance in a statistically rigorous way. This article describes the development of a process model, the assessment of key microstructural features to be incorporated into a microstructure simulation model, a novel approach to extract a constitutive equation to predict tensile properties in Ti-6Al-4V (Ti-64), and a probabilistic approach to measure the fidelity of the property model against real data. This integrated approach will provide designers a tool to vary process parameters and understand the influence on performance, enabling design and optimization for these highly visible manufacturing approaches.

  14. Accurate load prediction by BEM with airfoil data from 3D RANS simulations

    NASA Astrophysics Data System (ADS)

    Schneider, Marc S.; Nitzsche, Jens; Hennings, Holger

    2016-09-01

    In this paper, two methods for the extraction of airfoil coefficients from 3D CFD simulations of a wind turbine rotor are investigated, and these coefficients are used to improve the load prediction of a BEM code. The coefficients are extracted from a number of steady RANS simulations, using either averaging of velocities in annular sections, or an inverse BEM approach for determination of the induction factors in the rotor plane. It is shown that these 3D rotor polars are able to capture the rotational augmentation at the inner part of the blade as well as the load reduction by 3D effects close to the blade tip. They are used as input to a simple BEM code and the results of this BEM with 3D rotor polars are compared to the predictions of BEM with 2D airfoil coefficients plus common empirical corrections for stall delay and tip loss. While BEM with 2D airfoil coefficients produces a very different radial distribution of loads than the RANS simulation, the BEM with 3D rotor polars manages to reproduce the loads from RANS very accurately for a variety of load cases, as long as the blade pitch angle is not too different from the cases from which the polars were extracted.

  15. A SiPM-based isotropic-3D PET detector X'tal cube with a three-dimensional array of 1 mm(3) crystals.

    PubMed

    Yamaya, Taiga; Mitsuhashi, Takayuki; Matsumoto, Takahiro; Inadama, Naoko; Nishikido, Fumihiko; Yoshida, Eiji; Murayama, Hideo; Kawai, Hideyuki; Suga, Mikio; Watanabe, Mitsuo

    2011-11-07

    We are developing a novel, general purpose isotropic-3D PET detector X'tal cube which has high spatial resolution in all three dimensions. The research challenge for this detector is implementing effective detection of scintillation photons by covering six faces of a segmented crystal block with silicon photomultipliers (SiPMs). In this paper, we developed the second prototype of the X'tal cube for a proof-of-concept. We aimed at realizing an ultimate detector with 1.0 mm(3) cubic crystals, in contrast to our previous development using 3.0 mm(3) cubic crystals. The crystal block was composed of a 16 × 16 × 16 array of lutetium gadolinium oxyorthosilicate (LGSO) crystals 0.993 × 0.993 × 0.993 mm(3) in size. The crystals were optically glued together without inserting any reflector inside and 96 multi-pixel photon counters (MPPCs, S10931-50P, i.e. six faces each with a 4 × 4 array of MPPCs), each having a sensitive area of 3.0 × 3.0 mm(2), were optically coupled to the surfaces of the crystal block. Almost all 4096 crystals were identified through Anger-type calculation due to the finely adjusted reflector sheets inserted between the crystal block and light guides. The reflector sheets, which formed a belt of 0.5 mm width, were placed to cover half of the crystals of the second rows from the edges in order to improve identification performance of the crystals near the edges. Energy resolution of 12.7% was obtained at 511 keV with almost uniform light output for all crystal segments thanks to the effective detection of the scintillation photons.

  16. HST3D; a computer code for simulation of heat and solute transport in three-dimensional ground-water flow systems

    USGS Publications Warehouse

    Kipp, K.L.

    1987-01-01

    The Heat- and Soil-Transport Program (HST3D) simulates groundwater flow and associated heat and solute transport in three dimensions. The three governing equations are coupled through the interstitial pore velocity, the dependence of the fluid density on pressure, temperature, the solute-mass fraction , and the dependence of the fluid viscosity on temperature and solute-mass fraction. The solute transport equation is for only a single, solute species with possible linear equilibrium sorption and linear decay. Finite difference techniques are used to discretize the governing equations using a point-distributed grid. The flow-, heat- and solute-transport equations are solved , in turn, after a particle Gauss-reduction scheme is used to modify them. The modified equations are more tightly coupled and have better stability for the numerical solutions. The basic source-sink term represents wells. A complex well flow model may be used to simulate specified flow rate and pressure conditions at the land surface or within the aquifer, with or without pressure and flow rate constraints. Boundary condition types offered include specified value, specified flux, leakage, heat conduction, and approximate free surface, and two types of aquifer influence functions. All boundary conditions can be functions of time. Two techniques are available for solution of the finite difference matrix equations. One technique is a direct-elimination solver, using equations reordered by alternating diagonal planes. The other technique is an iterative solver, using two-line successive over-relaxation. A restart option is available for storing intermediate results and restarting the simulation at an intermediate time with modified boundary conditions. This feature also can be used as protection against computer system failure. Data input and output may be in metric (SI) units or inch-pound units. Output may include tables of dependent variables and parameters, zoned-contour maps, and plots of the

  17. Accurate 3D kinematic measurement of temporomandibular joint using X-ray fluoroscopic images

    NASA Astrophysics Data System (ADS)

    Yamazaki, Takaharu; Matsumoto, Akiko; Sugamoto, Kazuomi; Matsumoto, Ken; Kakimoto, Naoya; Yura, Yoshiaki

    2014-04-01

    Accurate measurement and analysis of 3D kinematics of temporomandibular joint (TMJ) is very important for assisting clinical diagnosis and treatment of prosthodontics and orthodontics, and oral surgery. This study presents a new 3D kinematic measurement technique of the TMJ using X-ray fluoroscopic images, which can easily obtain the TMJ kinematic data in natural motion. In vivo kinematics of the TMJ (maxilla and mandibular bone) is determined using a feature-based 2D/3D registration, which uses beads silhouette on fluoroscopic images and 3D surface bone models with beads. The 3D surface models of maxilla and mandibular bone with beads were created from CT scans data of the subject using the mouthpiece with the seven strategically placed beads. In order to validate the accuracy of pose estimation for the maxilla and mandibular bone, computer simulation test was performed using five patterns of synthetic tantalum beads silhouette images. In the clinical applications, dynamic movement during jaw opening and closing was conducted, and the relative pose of the mandibular bone with respect to the maxilla bone was determined. The results of computer simulation test showed that the root mean square errors were sufficiently smaller than 1.0 mm and 1.0 degree. In the results of clinical application, during jaw opening from 0.0 to 36.8 degree of rotation, mandibular condyle exhibited 19.8 mm of anterior sliding relative to maxillary articular fossa, and these measurement values were clinically similar to the previous reports. Consequently, present technique was thought to be suitable for the 3D TMJ kinematic analysis.

  18. A fast and accurate method to predict 2D and 3D aerodynamic boundary layer flows

    NASA Astrophysics Data System (ADS)

    Bijleveld, H. A.; Veldman, A. E. P.

    2014-12-01

    A quasi-simultaneous interaction method is applied to predict 2D and 3D aerodynamic flows. This method is suitable for offshore wind turbine design software as it is a very accurate and computationally reasonably cheap method. This study shows the results for a NACA 0012 airfoil. The two applied solvers converge to the experimental values when the grid is refined. We also show that in separation the eigenvalues remain positive thus avoiding the Goldstein singularity at separation. In 3D we show a flow over a dent in which separation occurs. A rotating flat plat is used to show the applicability of the method for rotating flows. The shown capabilities of the method indicate that the quasi-simultaneous interaction method is suitable for design methods for offshore wind turbine blades.

  19. Comparing the psychometric properties of two measures of wisdom: predicting forgiveness and psychological well-being with the Self-Assessed Wisdom Scale (SAWS) and the Three-Dimensional Wisdom Scale (3D-WS).

    PubMed

    Taylor, Matthew; Bates, Glen; Webster, Jeffrey Dean

    2011-03-01

    Two recently developed scales of wisdom were compared on their abilities to have their dimensional structure replicated and to predict relevant personality (i.e., forgiveness) and life satisfaction (i.e., psychological well-being) variables. One hundred and seventy-six primarily (71%) Australian participants ranging in age from 18 to 68 years (M = 36.60, SD = 12.07) completed an online survey of the Self-Assessed Wisdom Scale (SAWS; Webster, 2003, Journal of Adult Development, 10, 13-22; 2007, International Journal of Aging and Human Development, 65, 163-183), the Three-Dimensional Wisdom Scale (3D-WS; Ardelt, 2003, Journal of Gerontology: Psychological Sciences, 52B, 15-27), the Heartland Forgiveness Scale (Thompson et al., 2005, Journal of Personality, 73, 313-360), Ryff's (1989, Journal of Personality and Social Psychology, 57, 1069-1081) measure of psychological well-being (PWB), and a measure of social desirability (BIDR; Paulhus, 1984, Journal of Personality and Social Psychology, 46, 598-609). Results indicated that the dimensional structure of the SAWS, but not the 3D-WS, replicated, and the 3D-WS, but not the SAWS, was contaminated by a social desirability response bias. Both scales predicted equally well PWB and forgiveness in predicted directions. Implications for future use of both scales are discussed.

  20. Portable and accurate 3D scanner for breast implant design and reconstructive plastic surgery

    NASA Astrophysics Data System (ADS)

    Rigotti, Camilla; Borghese, Nunzio A.; Ferrari, Stefano; Baroni, Guido; Ferrigno, Giancarlo

    1998-06-01

    In order to evaluate the proper breast implant, the surgeon relies on a standard set of measurements manually taken on the subject. This approach does not allow to obtain an accurate reconstruction of the breast shape and asymmetries can easily arise after surgery. The purpose of this work is to present a method which can help the surgeon in the choice of the shape and dimensions of a prosthesis allowing for a perfect symmetry between the prosthesis and the controlateral breast and can be used as a 3D visual feedback in plastic surgery.

  1. Accurately measuring volume of soil samples using low cost Kinect 3D scanner

    NASA Astrophysics Data System (ADS)

    van der Sterre, B.; Hut, R.; Van De Giesen, N.

    2012-12-01

    The 3D scanner of the Kinect game controller can be used to increase the accuracy and efficiency of determining in situ soil moisture content. Soil moisture is one of the principal hydrological variables in both the water and energy interactions between soil and atmosphere. Current in situ measurements of soil moisture either rely on indirect measurements (of electromagnetic constants or heat capacity) or on physically taking a sample and weighing it in a lab. The bottleneck in accurately retrieving soil moisture using samples is the determining of the volume of the sample. Currently this is mostly done by the very time consuming "sand cone method" in which the volume were the sample used to sit is filled with sand. We show that 3D scanner that is part of the $150 game controller extension "Kinect" can be used to make 3D scans before and after taking the sample. The accuracy of this method is tested by scanning forms of known volume. This method is less time consuming and less error-prone than using a sand cone.

  2. Accurately measuring volume of soil samples using low cost Kinect 3D scanner

    NASA Astrophysics Data System (ADS)

    van der Sterre, Boy-Santhos; Hut, Rolf; van de Giesen, Nick

    2013-04-01

    The 3D scanner of the Kinect game controller can be used to increase the accuracy and efficiency of determining in situ soil moisture content. Soil moisture is one of the principal hydrological variables in both the water and energy interactions between soil and atmosphere. Current in situ measurements of soil moisture either rely on indirect measurements (of electromagnetic constants or heat capacity) or on physically taking a sample and weighing it in a lab. The bottleneck in accurately retrieving soil moisture using samples is the determining of the volume of the sample. Currently this is mostly done by the very time consuming "sand cone method" in which the volume were the sample used to sit is filled with sand. We show that 3D scanner that is part of the 150 game controller extension "Kinect" can be used to make 3D scans before and after taking the sample. The accuracy of this method is tested by scanning forms of known volume. This method is less time consuming and less error-prone than using a sand cone.

  3. WaveQ3D: Fast and accurate acoustic transmission loss (TL) eigenrays, in littoral environments

    NASA Astrophysics Data System (ADS)

    Reilly, Sean M.

    This study defines a new 3D Gaussian ray bundling acoustic transmission loss model in geodetic coordinates: latitude, longitude, and altitude. This approach is designed to lower the computation burden of computing accurate environmental effects in sonar training application by eliminating the need to transform the ocean environment into a collection of Nx2D Cartesian radials. This approach also improves model accuracy by incorporating real world 3D effects, like horizontal refraction, into the model. This study starts with derivations for a 3D variant of Gaussian ray bundles in this coordinate system. To verify the accuracy of this approach, acoustic propagation predictions of transmission loss, time of arrival, and propagation direction are compared to analytic solutions and other models. To validate the model's ability to predict real world phenomena, predictions of transmission loss and propagation direction are compared to at-sea measurements, in an environment where strong horizontal refraction effect have been observed. This model has been integrated into U.S. Navy active sonar training system applications, where testing has demonstrated its ability to improve transmission loss calculation speed without sacrificing accuracy.

  4. General formation of three-dimensional (3D) interconnected MxSy (M = Ni, Zn, and Fe)-graphene nanosheets-carbon nanotubes aerogels for lithium-ion batteries with excellent rate capability and cycling stability

    NASA Astrophysics Data System (ADS)

    Wang, Xiujuan; Liu, Xiaojie; Wang, Gang; Zhou, Yixuan; Wang, Hui

    2017-02-01

    Metal sulfides have a highly promising potential as anode materials for next-generation lithium-ion batteries (LIBs) due to their environmental friendliness, abundant resources, and low-cost. Unfortunately, the implementation of such novel anodes is severely hindered by their low electronic conductivity and large volume expansion during the repetitive lithiation/delithiation process. Herein, we report a specifically designed anode structure to overcome these obstacles, that is, to incorporate MxSy (M = Ni, Zn, and Fe) with graphene nanosheets (GNS) and carbon nanotubes (CNTs) to form three-dimensional interconnected MxSy-graphene nanosheets-carbon nanotubes aerogels. Morphology and structure results confirm that MxSy particles were uniformly and closely attached on the 3D complex network structure of GNS-CNT. As a result, when used as anode materials for half and full LIBs, the MxSy-GNS-CNT aerogels exhibit remarkable high reversible capacities, ultra-long cycle life, and super high rate performance (For example, the NiS-GNS-CNT, ZnS-GNS-CNT, and FeS2-GNS-CNT aerogels could deliver high capacities of 735, 800, and 850 mAh g-1 after 100 cycles, respectively). Our results indicate that 3D interconnected MxSy-GNS-CNT aerogels are promising anode materials for the next generation LIBs with high-performance.

  5. Three-dimensional display technologies.

    PubMed

    Geng, Jason

    2013-01-01

    The physical world around us is three-dimensional (3D), yet traditional display devices can show only two-dimensional (2D) flat images that lack depth (i.e., the third dimension) information. This fundamental restriction greatly limits our ability to perceive and to understand the complexity of real-world objects. Nearly 50% of the capability of the human brain is devoted to processing visual information [Human Anatomy & Physiology (Pearson, 2012)]. Flat images and 2D displays do not harness the brain's power effectively. With rapid advances in the electronics, optics, laser, and photonics fields, true 3D display technologies are making their way into the marketplace. 3D movies, 3D TV, 3D mobile devices, and 3D games have increasingly demanded true 3D display with no eyeglasses (autostereoscopic). Therefore, it would be very beneficial to readers of this journal to have a systematic review of state-of-the-art 3D display technologies.

  6. Initial Efficacy Results of RTOG 0319: Three-Dimensional Conformal Radiation Therapy (3D-CRT) Confined to the Region of the Lumpectomy Cavity for Stage I/ II Breast Carcinoma

    SciTech Connect

    Vicini, Frank; Winter, Kathryn; Wong, John

    2010-07-15

    Purpose: This prospective study (Radiation Therapy Oncology Group 0319) examines the use of three-dimensional conformal external beam radiotherapy (3D-CRT) to deliver accelerated partial breast irradiation (APBI). Initial data on efficacy and toxicity are presented. Methods and Materials: Patients with Stage I or II breast cancer with lesions {<=}3 cm, negative margins and with {<=}3 positive nodes were eligible. The 3D-CRT was 38.5 Gy in 3.85 Gy/fraction delivered 2x/day. Ipsilateral breast, ipsilateral nodal, contralateral breast, and distant failure (IBF, INF, CBF, DF) were estimated using the cumulative incidence method. Mastectomy-free, disease-free, and overall survival (MFS, DFS, OS) were recorded. The National Cancer Institute Common Terminology Criteria for Adverse Events, version 3, was used to grade acute and late toxicity. Results: Fifty-eight patients were entered and 52 patients are eligible and evaluable for efficacy. The median age of patients was 61 years with the following characteristics: 46% tumor size <1 cm; 87% invasive ductal histology; 94% American Joint Committee on Cancer Stage I; 65% postmenopausal; 83% no chemotherapy; and 71% with no hormone therapy. Median follow-up is 4.5 years (1.7-4.8). Four-year estimates (95% CI) of efficacy are: IBF 6% (0-12%) [4% within field (0-9%)]; INF 2% (0-6%); CBF 0%; DF 8% (0-15%); MFS 90% (78-96%); DFS 84% (71-92%); and OS 96% (85-99%). Only two (4%) Grade 3 toxicities were observed. Conclusions: Initial efficacy and toxicity using 3D-CRT to deliver APBI appears comparable to other experiences with similar follow-up. However, additional patients, further follow-up, and mature Phase III data are needed to evaluate the extent of application, limitations, and value of this particular form of APBI.

  7. A new 3D Eikonal solver for accurate traveltimes, take-off angles and amplitudes

    NASA Astrophysics Data System (ADS)

    Noble, Mark; Gesret, Alexandrine

    2013-04-01

    The finite-difference approximation to the eikonal equation was first introduced by J.Vidale in 1988 to propagate first-arrival times throughout a 2D or 3D gridded velocity model. Even today this method is still very attractive from a computational point of view when dealing with large datasets. Among many domains of application, the eikonal solver may be used for 2-D or 3-D depth migration, tomography or microseismicity data analysis. The original 3D method proposed by Vidale in 1990 did exhibit some degree of travel time error that may lead to poor image focusing in migration or inaccurate velocities estimated via tomographic inversion. The method even failed when large and sharp velocity contrasts were encountered. To try and overcome these limitations many authors proposed alternative algorithms, incorporating new finite-difference operators and/or new schemes of implementing the operators to propagate the travel times through the velocity model. If many recently published algorithms for resolving the 3D eikonal equation do yield fairly accurate travel times for most applications, the spatial derivatives of travel times remain very approximate and prevent reliable computation of auxiliary quantities such as take-off angle and amplitude. This limitation is due to the fact that the finite-difference operators locally assume that the wavefront is flat (plane wave). This assumption is in particularly wrong when close to the source where a spherical approximation would be more suitable. To overcome this singularity at the source, some authors proposed an adaptive method that reduces inaccuracies, however, the cost is more algorithmic complexity. The objective of this study is to develop an efficient simple 3D eikonal solver that is able to: overcome the problem of the source singularity, handle velocity models that exhibit strong vertical and horizontal velocity variations, use different grid spacing in x, y and z axis of model. The final goal is of course to

  8. Three-dimensional conformal setup (3D-CSU) of patients using the coordinate system provided by three internal fiducial markers and two orthogonal diagnostic X-ray systems in the treatment room

    SciTech Connect

    Shirato, Hiroki . E-mail: hshirato@radi.med.hokudai.ac.jp; Oita, Masataka; Fujita, Katsuhisa; Shimizu, Shinichi; Onimaru, Rikiya; Uegaki, Shinji; Watanabe, Yoshiharu; Kato, Norio; Miyasaka, Kazuo

    2004-10-01

    Purpose: To test the accuracy of a system for correcting for the rotational error of the clinical target volume (CTV) without having to reposition the patient using three fiducial markers and two orthogonal fluoroscopic images. We call this system 'three-dimensional conformal setup' (3D-CSU). Methods and materials: Three 2.0-mm gold markers are inserted into or adjacent to the CTV. On the treatment couch, the actual positions of the three markers are calculated based on two orthogonal fluoroscopies crossing at the isocenter of the linear accelerator. Discrepancy of the actual coordinates of gravity center of three markers from its planned coordinates is calculated. Translational setup error is corrected by adjustment of the treatment couch. The rotation angles ({alpha}, {beta}, {gamma}) of the coordinates of the actual CTV relative to the planned CTV are calculated around the lateral (x), craniocaudal (y), and anteroposterior (z) axes of the planned CTV. The angles of the gantry head, collimator, and treatment couch of the linear accelerator are adjusted according to the rotation of the actual coordinates of the tumor in relation to the planned coordinates. We have measured the accuracy of 3D-CSU using a static cubic phantom. Results: The gravity center of the phantom was corrected within 0.9 {+-} 0.3 mm (mean {+-} SD), 0.4 {+-} 0.2 mm, and 0.6 {+-} 0.2 mm for the rotation of the phantom from 0-30 degrees around the x, y, and z axes, respectively, every 5 degrees. Dose distribution was shown to be consistent with the planned dose distribution every 10 degrees of the rotation from 0-30 degrees. The mean rotational error after 3D-CSU was -0.4 {+-} 0.4 (mean {+-} SD), -0.2 {+-} 0.4, and 0.0 {+-} 0.5 degrees around the x, y, and z axis, respectively, for the rotation from 0-90 degrees. Conclusions: Phantom studies showed that 3D-CSU is useful for performing rotational correction of the target volume without correcting the position of the patient on the treatment couch

  9. Searching surface orientation of microscopic objects for accurate 3D shape recovery.

    PubMed

    Shim, Seong-O; Mahmood, Muhammad Tariq; Choi, Tae-Sun

    2012-05-01

    In this article, we propose a new shape from focus (SFF) method to estimate 3D shape of microscopic objects using surface orientation cue of each object patch. Most of the SFF algorithms compute the focus value of a pixel from the information of neighboring pixels lying on the same image frame based on an assumption that the small object patch corresponding to the small neighborhood of a pixel is a plane parallel to the focal plane. However, this assumption fails in the optics with limited depth of field where the neighboring pixels of an image have different degree of focus. To overcome this problem, we try to search the surface orientation of the small object patch corresponding to each pixel in the image sequence. Searching of the surface orientation is done indirectly by principal component analysis. Then, the focus value of each pixel is computed from the neighboring pixels lying on the surface perpendicular to the corresponding surface orientation. Experimental results on synthetic and real microscopic objects show that the proposed method produces more accurate 3D shape in comparison to the existing techniques.

  10. Method for accurate sizing of pulmonary vessels from 3D medical images

    NASA Astrophysics Data System (ADS)

    O'Dell, Walter G.

    2015-03-01

    Detailed characterization of vascular anatomy, in particular the quantification of changes in the distribution of vessel sizes and of vascular pruning, is essential for the diagnosis and management of a variety of pulmonary vascular diseases and for the care of cancer survivors who have received radiation to the thorax. Clinical estimates of vessel radii are typically based on setting a pixel intensity threshold and counting how many "On" pixels are present across the vessel cross-section. A more objective approach introduced recently involves fitting the image with a library of spherical Gaussian filters and utilizing the size of the best matching filter as the estimate of vessel diameter. However, both these approaches have significant accuracy limitations including mis-match between a Gaussian intensity distribution and that of real vessels. Here we introduce and demonstrate a novel approach for accurate vessel sizing using 3D appearance models of a tubular structure along a curvilinear trajectory in 3D space. The vessel branch trajectories are represented with cubic Hermite splines and the tubular branch surfaces represented as a finite element surface mesh. An iterative parameter adjustment scheme is employed to optimally match the appearance models to a patient's chest X-ray computed tomography (CT) scan to generate estimates for branch radii and trajectories with subpixel resolution. The method is demonstrated on pulmonary vasculature in an adult human CT scan, and on 2D simulated test cases.

  11. In Situ Casting and Imaging of the Rat Airway Tree for Accurate 3D Reconstruction

    PubMed Central

    Jacob, Richard E.; Colby, Sean M.; Kabilan, Senthil; Einstein, Daniel R.; Carson, James P.

    2014-01-01

    The use of anatomically accurate, animal-specific airway geometries is important for understanding and modeling the physiology of the respiratory system. One approach for acquiring detailed airway architecture is to create a bronchial cast of the conducting airways. However, typical casting procedures either do not faithfully preserve the in vivo branching angles or produce rigid casts that when removed for imaging are fragile and thus easily damaged. We address these problems by creating an in situ bronchial cast of the conducting airways in rats that can be subsequently imaged in situ using 3D micro-CT imaging. We also demonstrate that deformations in airway branch angles resulting from the casting procedure are small, and that these angle deformations can be reversed through an interactive adjustment of the segmented cast geometry. Animal work was approved by the Institutional Animal Care and Use Committee of Pacific Northwest National Laboratory. PMID:23786464

  12. Three dimensional interactive display

    NASA Technical Reports Server (NTRS)

    Vranish, John M. (Inventor)

    2005-01-01

    A three-dimensional (3-D) interactive display and method of forming the same, includes a transparent capaciflector (TC) camera formed on a transparent shield layer on the screen surface. A first dielectric layer is formed on the shield layer. A first wire layer is formed on the first dielectric layer. A second dielectric layer is formed on the first wire layer. A second wire layer is formed on the second dielectric layer. Wires on the first wire layer and second wire layer are grouped into groups of parallel wires with a turnaround at one end of each group and a sensor pad at the opposite end. An operational amplifier is connected to each of the sensor pads and the shield pad biases the pads and receives a signal from connected sensor pads in response to intrusion of a probe. The signal is proportional to probe location with respect to the monitor screen.

  13. Fast, automatic, and accurate catheter reconstruction in HDR brachytherapy using an electromagnetic 3D tracking system

    SciTech Connect

    Poulin, Eric; Racine, Emmanuel; Beaulieu, Luc; Binnekamp, Dirk

    2015-03-15

    Purpose: In high dose rate brachytherapy (HDR-B), current catheter reconstruction protocols are relatively slow and error prone. The purpose of this technical note is to evaluate the accuracy and the robustness of an electromagnetic (EM) tracking system for automated and real-time catheter reconstruction. Methods: For this preclinical study, a total of ten catheters were inserted in gelatin phantoms with different trajectories. Catheters were reconstructed using a 18G biopsy needle, used as an EM stylet and equipped with a miniaturized sensor, and the second generation Aurora{sup ®} Planar Field Generator from Northern Digital Inc. The Aurora EM system provides position and orientation value with precisions of 0.7 mm and 0.2°, respectively. Phantoms were also scanned using a μCT (GE Healthcare) and Philips Big Bore clinical computed tomography (CT) system with a spatial resolution of 89 μm and 2 mm, respectively. Reconstructions using the EM stylet were compared to μCT and CT. To assess the robustness of the EM reconstruction, five catheters were reconstructed twice and compared. Results: Reconstruction time for one catheter was 10 s, leading to a total reconstruction time inferior to 3 min for a typical 17-catheter implant. When compared to the μCT, the mean EM tip identification error was 0.69 ± 0.29 mm while the CT error was 1.08 ± 0.67 mm. The mean 3D distance error was found to be 0.66 ± 0.33 mm and 1.08 ± 0.72 mm for the EM and CT, respectively. EM 3D catheter trajectories were found to be more accurate. A maximum difference of less than 0.6 mm was found between successive EM reconstructions. Conclusions: The EM reconstruction was found to be more accurate and precise than the conventional methods used for catheter reconstruction in HDR-B. This approach can be applied to any type of catheters and applicators.

  14. Towards Contactless, Low-Cost and Accurate 3D Fingerprint Identification.

    PubMed

    Kumar, Ajay; Kwong, Cyril

    2015-03-01

    Human identification using fingerprint impressions has been widely studied and employed for more than 2000 years. Despite new advancements in the 3D imaging technologies, widely accepted representation of 3D fingerprint features and matching methodology is yet to emerge. This paper investigates 3D representation of widely employed 2D minutiae features by recovering and incorporating (i) minutiae height z and (ii) its 3D orientation φ information and illustrates an effective matching strategy for matching popular minutiae features extended in 3D space. One of the obstacles of the emerging 3D fingerprint identification systems to replace the conventional 2D fingerprint system lies in their bulk and high cost, which is mainly contributed from the usage of structured lighting system or multiple cameras. This paper attempts to addresses such key limitations of the current 3D fingerprint technologies bydeveloping the single camera-based 3D fingerprint identification system. We develop a generalized 3D minutiae matching model and recover extended 3D fingerprint features from the reconstructed 3D fingerprints. 2D fingerprint images acquired for the 3D fingerprint reconstruction can themselves be employed for the performance improvement and have been illustrated in the work detailed in this paper. This paper also attempts to answer one of the most fundamental questions on the availability of inherent discriminable information from 3D fingerprints. The experimental results are presented on a database of 240 clients 3D fingerprints, which is made publicly available to further research efforts in this area, and illustrate the discriminant power of 3D minutiae representation and matching to achieve performance improvement.

  15. Accurate B-spline-based 3-D interpolation scheme for digital volume correlation.

    PubMed

    Ren, Maodong; Liang, Jin; Wei, Bin

    2016-12-01

    An accurate and efficient 3-D interpolation scheme, based on sampling theorem and Fourier transform technique, is proposed to reduce the sub-voxel matching error caused by intensity interpolation bias in digital volume correlation. First, the influence factors of the interpolation bias are investigated theoretically using the transfer function of an interpolation filter (henceforth filter) in the Fourier domain. A law that the positional error of a filter can be expressed as a function of fractional position and wave number is found. Then, considering the above factors, an optimized B-spline-based recursive filter, combining B-spline transforms and least squares optimization method, is designed to virtually eliminate the interpolation bias in the process of sub-voxel matching. Besides, given each volumetric image containing different wave number ranges, a Gaussian weighting function is constructed to emphasize or suppress certain of wave number ranges based on the Fourier spectrum analysis. Finally, a novel software is developed and series of validation experiments were carried out to verify the proposed scheme. Experimental results show that the proposed scheme can reduce the interpolation bias to an acceptable level.

  16. Accurate nonrelativistic ground-state energies of 3d transition metal atoms

    SciTech Connect

    Scemama, A.; Applencourt, T.; Giner, E.; Caffarel, M.

    2014-12-28

    We present accurate nonrelativistic ground-state energies of the transition metal atoms of the 3d series calculated with Fixed-Node Diffusion Monte Carlo (FN-DMC). Selected multi-determinantal expansions obtained with the CIPSI (Configuration Interaction using a Perturbative Selection made Iteratively) method and including the most prominent determinants of the full configuration interaction expansion are used as trial wavefunctions. Using a maximum of a few tens of thousands determinants, fixed-node errors on total DMC energies are found to be greatly reduced for some atoms with respect to those obtained with Hartree-Fock nodes. To the best of our knowledge, the FN-DMC/(CIPSI nodes) ground-state energies presented here are the lowest variational total energies reported so far. They differ from the recently recommended non-variational values of McCarthy and Thakkar [J. Chem. Phys. 136, 054107 (2012)] only by a few percents of the correlation energy. Thanks to the variational property of FN-DMC total energies, our results provide exact lower bounds for the absolute value of all-electron correlation energies, |E{sub c}|.

  17. Accurate 3D reconstruction by a new PDS-OSEM algorithm for HRRT

    NASA Astrophysics Data System (ADS)

    Chen, Tai-Been; Horng-Shing Lu, Henry; Kim, Hang-Keun; Son, Young-Don; Cho, Zang-Hee

    2014-03-01

    State-of-the-art high resolution research tomography (HRRT) provides high resolution PET images with full 3D human brain scanning. But, a short time frame in dynamic study causes many problems related to the low counts in the acquired data. The PDS-OSEM algorithm was proposed to reconstruct the HRRT image with a high signal-to-noise ratio that provides accurate information for dynamic data. The new algorithm was evaluated by simulated image, empirical phantoms, and real human brain data. Meanwhile, the time activity curve was adopted to validate a reconstructed performance of dynamic data between PDS-OSEM and OP-OSEM algorithms. According to simulated and empirical studies, the PDS-OSEM algorithm reconstructs images with higher quality, higher accuracy, less noise, and less average sum of square error than those of OP-OSEM. The presented algorithm is useful to provide quality images under the condition of low count rates in dynamic studies with a short scan time.

  18. Automatic pose initialization for accurate 2D/3D registration applied to abdominal aortic aneurysm endovascular repair

    NASA Astrophysics Data System (ADS)

    Miao, Shun; Lucas, Joseph; Liao, Rui

    2012-02-01

    Minimally invasive abdominal aortic aneurysm (AAA) stenting can be greatly facilitated by overlaying the preoperative 3-D model of the abdominal aorta onto the intra-operative 2-D X-ray images. Accurate 2-D/3-D registration in 3-D space makes the 2-D/3-D overlay robust to the change of C-Arm angulations. By far, the 2-D/3-D registration methods based on simulated X-ray projection images using multiple image planes have been shown to be able to provide satisfactory 3-D registration accuracy. However, one drawback of the intensity-based 2-D/3-D registration methods is that the similarity measure is usually highly non-convex and hence the optimizer can easily be trapped into local minima. User interaction therefore is often needed in the initialization of the position of the 3-D model in order to get a successful 2-D/3-D registration. In this paper, a novel 3-D pose initialization technique is proposed, as an extension of our previously proposed bi-plane 2-D/3-D registration method for AAA intervention [4]. The proposed method detects vessel bifurcation points and spine centerline in both 2-D and 3-D images, and utilizes landmark information to bring the 3-D volume into a 15mm capture range. The proposed landmark detection method was validated on real dataset, and is shown to be able to provide a good initialization for 2-D/3-D registration in [4], thus making the workflow fully automatic.

  19. Three-dimensional (3-D) fluorescence spectroscopy analysis of the fluorescent dissolved organic matter released by the marine toxic dinoflagellate Alexandrium catenella exposed to metal stress by zinc or lead.

    PubMed

    Herzi, Faouzi; Jean, Natacha; Sakka Hlaili, Asma; Mounier, Stéphane

    2014-08-01

    We investigated the effects of zinc or lead on growth and on exudation of fluorescent dissolved organic matter (FDOM) by the marine toxic dinoflagellate Alexandrium catenella (Whedon & Kofoid) Balech. The species was exposed to increasing free zinc (1.34 × 10(-7) M-3.98 × 10(-6) M) or lead (5.13 × 10(-9) M-1.82 × 10(-7) M) concentra-tions. Low metal levels ([Zn(2+) ] = 1.34 × 10(-7) M; [Pb(2+) ] = 5.13 × 10(-9) M) had no effect on cell growth. Toxic effects were observed from higher metal contamination ([Zn(2+) ] = 3.98 × 10(-6) M; [Pb(2+) ] = 6.54 × 10(-8) M), as a conversion of vegetative cells into cysts. Analysis of the released FDOM by three-dimensional (3-D) fluorescence spectroscopy was achieved, using the parallel factor analysis (PARAFAC). The PARAFAC modeling revealed four components associated with two contributions: one related to the biological activity; the other linked to the organic matter decomposition in the culture medium. The C1 component combined a tryptophan peak and characteristics of humic substances, whereas the C2 component was considered as a tryptophan protein fluorophore. The two others C3 and C4 components were associated with marine organic matter production. Relea-sed fluorescent substances were induced by low ([Zn(2+) ]= 1.34 × 10(-7) M; [Pb(2+) ] = 5.13 × 10(-9) M) and moderate ([Zn(2+) ] = 6.21 × 10(-7) M; [Pb(2+) ] = 2.64× 10(-9) M) metal concentrations, suggesting the activation of cellular mechanisms in response to metal stress, to exudate FDOM that could complex metal cations and reduce their toxicity toward A. catenella cells.

  20. Looking down is looking up. [Three-dimensional seismic surveying

    SciTech Connect

    Stelzer, D.A.

    1983-01-01

    Filling a need of oil specialists to see subsurface formations accurately is a new, three-dimensional (3-D) image-maker. Using computers, geophysicists manipulate seismic data to create accurate pictures of the depth and breadth of subsurface structures. Aboveground-generated sound waves extended thousands of feet into earth layers are picked up by energy-sensing cables, amplified, and recorded on magnetic tape. Seismic impulses reflected from below-surface strata are converted into 3-D images and computerized, allowing new viewing perspectives. Future drillings will confirm the new technique's reliability. 7 figures.

  1. Machine learning and synthetic aperture refocusing approach for more accurate masking of fish bodies in 3D PIV data

    NASA Astrophysics Data System (ADS)

    Ford, Logan; Bajpayee, Abhishek; Techet, Alexandra

    2015-11-01

    3D particle image velocimetry (PIV) is becoming a popular technique to study biological flows. PIV images that contain fish or other animals around which flow is being studied, need to be appropriately masked in order to remove the animal body from the 3D reconstructed volumes prior to calculating particle displacement vectors. Presented here is a machine learning and synthetic aperture (SA) refocusing based approach for more accurate masking of fish from reconstructed intensity fields for 3D PIV purposes. Using prior knowledge about the 3D shape and appearance of the fish along with SA refocused images at arbitrarily oriented focal planes, the location and orientation of a fish in a reconstructed volume can be accurately determined. Once the location and orientation of a fish in a volume is determined, it can be masked out.

  2. Three dimensional characterization and archiving system

    SciTech Connect

    Sebastian, R.L.; Clark, R.; Gallman, P.

    1996-04-01

    The Three Dimensional Characterization and Archiving System (3D-ICAS) is being developed as a remote system to perform rapid in situ analysis of hazardous organics and radionuclide contamination on structural materials. Coleman Research and its subcontractors, Thermedics Detection, Inc. (TD) and the University of Idaho (UI) are in the second phase of a three phase program to develop 3D-ICAS to support Decontamination and Decommissioning (D and D) operations. Accurate physical characterization of surfaces and the radioactive and organic is a critical D and D task. Surface characterization includes identification of potentially dangerous inorganic materials, such as asbestos and transite. Real-time remotely operable characterization instrumentation will significantly advance the analysis capabilities beyond those currently employed. Chemical analysis is a primary area where the characterization process will be improved. The 3D-ICAS system robotically conveys a multisensor probe near the surfaces to be inspected. The sensor position and orientation are monitored and controlled using coherent laser radar (CLR) tracking. The CLR also provides 3D facility maps which establish a 3D world view within which the robotic sensor system can operate.

  3. Accurate, full chip 3D electromagnetic field model for non-Manhattan mask corners

    NASA Astrophysics Data System (ADS)

    Lam, Michael; Clifford, Chris; Oliver, Michael; Fryer, David; Tejnil, Edita; Adam, Kostas

    2015-03-01

    The physical process of mask manufacturing produces absorber geometry with significantly less than 90 degree fidelity at corners. The non-Manhattan mask geometry is an essential contributor to the aerial image and resulting patterning performance through focus. Current state of the art models for corner rounding employ "chopping" a 90 degree mask corner, replacing the corner with a small 45 degree edge. In this paper, a methodology is presented to approximate the impact of 3D EMF effects introduced by corners with rounded edges. The approach is integrated into a full chip 3D mask simulation methodology based on the Domain Decomposition Method (DDM) with edge to edge crosstalk correction.

  4. Accurate Diagnosis of Severe Hypospadias Using 2D and 3D Ultrasounds

    PubMed Central

    López Ramón y Cajal, Carlos; Marín Ortiz, Elena; Sarmiento Carrera, Nerea

    2016-01-01

    The hypospadias is the most common urogenital anomaly of male neonates but the prenatal diagnosis of this is often missed before birth. We present the prenatal diagnosis of a severe penoscrotal hypospadias using 2D and 3D ultrasounds. 3D sonography allowed us the best evaluation of the genitals and their anatomical relations. This ample detailed study allowed us to show the findings to the parents and the pediatric surgeon and to configure the best information about the prognosis and surgical treatment. PMID:27774326

  5. SU-E-J-08: A Hybrid Three Dimensional Registration Framework for Image-Guided Accurate Radiotherapy System ARTS-IGRT

    SciTech Connect

    Wu, Q; Pei, X; Cao, R; Hu, L; Wu, Y

    2014-06-01

    Purpose: The purpose of this work was to develop a registration framework and method based on the software platform of ARTS-IGRT and implement in C++ based on ITK libraries to register CT images and CBCT images. ARTS-IGRT was a part of our self-developed accurate radiation planning system ARTS. Methods: Mutual information (MI) registration treated each voxel equally. Actually, different voxels even having same intensity should be treated differently in the registration procedure. According to their importance values calculated from self-information, a similarity measure was proposed which combined the spatial importance of a voxel with MI (S-MI). For lung registration, Firstly, a global alignment method was adopted to minimize the margin error and achieve the alignment of these two images on the whole. The result obtained at the low resolution level was then interpolated to become the initial conditions for the higher resolution computation. Secondly, a new similarity measurement S-MI was established to quantify how close the two input image volumes were to each other. Finally, Demons model was applied to compute the deformable map. Results: Registration tools were tested for head-neck and lung images and the average region was 128*128*49. The rigid registration took approximately 2 min and converged 10% faster than traditional MI algorithm, the accuracy reached 1mm for head-neck images. For lung images, the improved symmetric Demons registration process was completed in an average of 5 min using a 2.4GHz dual core CPU. Conclusion: A registration framework was developed to correct patient's setup according to register the planning CT volume data and the daily reconstructed 3D CBCT data. The experiments showed that the spatial MI algorithm can be adopted for head-neck images. The improved Demons deformable registration was more suitable to lung images, and rigid alignment should be applied before deformable registration to get more accurate result. Supported by

  6. Three-dimensional display technologies

    PubMed Central

    Geng, Jason

    2014-01-01

    The physical world around us is three-dimensional (3D), yet traditional display devices can show only two-dimensional (2D) flat images that lack depth (i.e., the third dimension) information. This fundamental restriction greatly limits our ability to perceive and to understand the complexity of real-world objects. Nearly 50% of the capability of the human brain is devoted to processing visual information [Human Anatomy & Physiology (Pearson, 2012)]. Flat images and 2D displays do not harness the brain’s power effectively. With rapid advances in the electronics, optics, laser, and photonics fields, true 3D display technologies are making their way into the marketplace. 3D movies, 3D TV, 3D mobile devices, and 3D games have increasingly demanded true 3D display with no eyeglasses (autostereoscopic). Therefore, it would be very beneficial to readers of this journal to have a systematic review of state-of-the-art 3D display technologies. PMID:25530827

  7. The effect of porosity on cell ingrowth into accurately defined, laser-made, polylactide-based 3D scaffolds

    NASA Astrophysics Data System (ADS)

    Danilevicius, Paulius; Georgiadi, Leoni; Pateman, Christopher J.; Claeyssens, Frederik; Chatzinikolaidou, Maria; Farsari, Maria

    2015-05-01

    The aim of this study is to demonstrate the accuracy required for the investigation of the role of solid scaffolds' porosity in cell proliferation. We therefore present a qualitative investigation into the effect of porosity on MC3T3-E1 pre-osteoblastic cell ingrowth of three-dimensional (3D) scaffolds fabricated by direct femtosecond laser writing. The material we used is a purpose made photosensitive pre-polymer based on polylactide. We designed and fabricated complex, geometry-controlled 3D scaffolds with pore sizes ranging from 25 to 110 μm, representing porosities 70%, 82%, 86%, and 90%. The 70% porosity scaffolds did not support cell growth initially and in the long term. For the other porosities, we found a strong adhesion of the pre-osteoblastic cells from the first hours after seeding and a remarkable proliferation increase after 3 weeks and up to 8 weeks. The 86% porosity scaffolds exhibited a higher efficiency compared to 82% and 90%. In addition, bulk material degradation studies showed that the employed, highly-acrylated polylactide is degradable. These findings support the potential use of the proposed material and the scaffold fabrication technique in bone tissue engineering.

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

    NASA Astrophysics Data System (ADS)

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

    1998-01-01

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

  9. Three dimensional strained semiconductors

    DOEpatents

    Voss, Lars; Conway, Adam; Nikolic, Rebecca J.; Leao, Cedric Rocha; Shao, Qinghui

    2016-11-08

    In one embodiment, an apparatus includes a three dimensional structure comprising a semiconductor material, and at least one thin film in contact with at least one exterior surface of the three dimensional structure for inducing a strain in the structure, the thin film being characterized as providing at least one of: an induced strain of at least 0.05%, and an induced strain in at least 5% of a volume of the three dimensional structure. In another embodiment, a method includes forming a three dimensional structure comprising a semiconductor material, and depositing at least one thin film on at least one surface of the three dimensional structure for inducing a strain in the structure, the thin film being characterized as providing at least one of: an induced strain of at least 0.05%, and an induced strain in at least 5% of a volume of the structure.

  10. Hipparcos makes an accurate 3-D chart of an important star cluster

    NASA Astrophysics Data System (ADS)

    1998-02-01

    Star clusters are crucial for understanding the lives of the stars everywhere, because all the members of a cluster formed at the same time from the same raw materials. Astrophysicists can see how the evolution of each star depends on its mass and chemical composition. The heavier a star is, the more intensely it burns and the faster it consumes its thermonuclear fuel. But the accuracy of the theories has been limited hitherto by inaccuracies in the observations. The brightest members of Hyades are visible to the naked eye, in the constellation Taurus. As the nearest moderately rich star cluster, the Hyades have loomed large in astrophysics for more than a century. Contradictory results for the distance of the star cluster left big question marks for the theorists, and even recent observations with the Hubble Space Telescope seemed only to deepen the mystery. Astronomers from ESA, Leiden Observatory, Observatoire de Paris-Meudon, University of Lausanne and Observatoire de la Côte d'Azur joined forces to analyse the data on the Hyades cluster contained in the Hipparcos Catalogue published last year. Their results will appear in the March issue of the European journal Astronomy & Astrophysics. The distance to the centre of the Hyades cluster is 151 light-years (46.34 parsecs) with an uncertainty of less than one light-year (0.27 parsec). From astrophysical theory the astronomers can date the birth of the Hyades at 625 million years ago, when only the most primitive animals lived on the Earth. The cluster has done well to survive so long.The individual stars of the Hyades are bound together by the gravity of the cluster as a whole, and their collective and individual motions are also plotted by Hipparcos. The result is a crisp 3-D motion picture of the cluster. An animation is available on the Internet (see note below). Outlying members sharing the same general motion can now be added to the Hyades tribe, while other candidate members are rejected on grounds of

  11. Quick, Accurate, Smart: 3D Computer Vision Technology Helps Assessing Confined Animals' Behaviour.

    PubMed

    Barnard, Shanis; Calderara, Simone; Pistocchi, Simone; Cucchiara, Rita; Podaliri-Vulpiani, Michele; Messori, Stefano; Ferri, Nicola

    2016-01-01

    Mankind directly controls the environment and lifestyles of several domestic species for purposes ranging from production and research to conservation and companionship. These environments and lifestyles may not offer these animals the best quality of life. Behaviour is a direct reflection of how the animal is coping with its environment. Behavioural indicators are thus among the preferred parameters to assess welfare. However, behavioural recording (usually from video) can be very time consuming and the accuracy and reliability of the output rely on the experience and background of the observers. The outburst of new video technology and computer image processing gives the basis for promising solutions. In this pilot study, we present a new prototype software able to automatically infer the behaviour of dogs housed in kennels from 3D visual data and through structured machine learning frameworks. Depth information acquired through 3D features, body part detection and training are the key elements that allow the machine to recognise postures, trajectories inside the kennel and patterns of movement that can be later labelled at convenience. The main innovation of the software is its ability to automatically cluster frequently observed temporal patterns of movement without any pre-set ethogram. Conversely, when common patterns are defined through training, a deviation from normal behaviour in time or between individuals could be assessed. The software accuracy in correctly detecting the dogs' behaviour was checked through a validation process. An automatic behaviour recognition system, independent from human subjectivity, could add scientific knowledge on animals' quality of life in confinement as well as saving time and resources. This 3D framework was designed to be invariant to the dog's shape and size and could be extended to farm, laboratory and zoo quadrupeds in artificial housing. The computer vision technique applied to this software is innovative in non

  12. Quick, Accurate, Smart: 3D Computer Vision Technology Helps Assessing Confined Animals’ Behaviour

    PubMed Central

    Calderara, Simone; Pistocchi, Simone; Cucchiara, Rita; Podaliri-Vulpiani, Michele; Messori, Stefano; Ferri, Nicola

    2016-01-01

    Mankind directly controls the environment and lifestyles of several domestic species for purposes ranging from production and research to conservation and companionship. These environments and lifestyles may not offer these animals the best quality of life. Behaviour is a direct reflection of how the animal is coping with its environment. Behavioural indicators are thus among the preferred parameters to assess welfare. However, behavioural recording (usually from video) can be very time consuming and the accuracy and reliability of the output rely on the experience and background of the observers. The outburst of new video technology and computer image processing gives the basis for promising solutions. In this pilot study, we present a new prototype software able to automatically infer the behaviour of dogs housed in kennels from 3D visual data and through structured machine learning frameworks. Depth information acquired through 3D features, body part detection and training are the key elements that allow the machine to recognise postures, trajectories inside the kennel and patterns of movement that can be later labelled at convenience. The main innovation of the software is its ability to automatically cluster frequently observed temporal patterns of movement without any pre-set ethogram. Conversely, when common patterns are defined through training, a deviation from normal behaviour in time or between individuals could be assessed. The software accuracy in correctly detecting the dogs’ behaviour was checked through a validation process. An automatic behaviour recognition system, independent from human subjectivity, could add scientific knowledge on animals’ quality of life in confinement as well as saving time and resources. This 3D framework was designed to be invariant to the dog’s shape and size and could be extended to farm, laboratory and zoo quadrupeds in artificial housing. The computer vision technique applied to this software is innovative in non

  13. Accurate 3d Textured Models of Vessels for the Improvement of the Educational Tools of a Museum

    NASA Astrophysics Data System (ADS)

    Soile, S.; Adam, K.; Ioannidis, C.; Georgopoulos, A.

    2013-02-01

    Besides the demonstration of the findings, modern museums organize educational programs which aim to experience and knowledge sharing combined with entertainment rather than to pure learning. Toward that effort, 2D and 3D digital representations are gradually replacing the traditional recording of the findings through photos or drawings. The present paper refers to a project that aims to create 3D textured models of two lekythoi that are exhibited in the National Archaeological Museum of Athens in Greece; on the surfaces of these lekythoi scenes of the adventures of Odysseus are depicted. The project is expected to support the production of an educational movie and some other relevant interactive educational programs for the museum. The creation of accurate developments of the paintings and of accurate 3D models is the basis for the visualization of the adventures of the mythical hero. The data collection was made by using a structured light scanner consisting of two machine vision cameras that are used for the determination of geometry of the object, a high resolution camera for the recording of the texture, and a DLP projector. The creation of the final accurate 3D textured model is a complicated and tiring procedure which includes the collection of geometric data, the creation of the surface, the noise filtering, the merging of individual surfaces, the creation of a c-mesh, the creation of the UV map, the provision of the texture and, finally, the general processing of the 3D textured object. For a better result a combination of commercial and in-house software made for the automation of various steps of the procedure was used. The results derived from the above procedure were especially satisfactory in terms of accuracy and quality of the model. However, the procedure was proved to be time consuming while the use of various software packages presumes the services of a specialist.

  14. Investigating the accuracy of microstereotactic-body-radiotherapy utilizing anatomically accurate 3D printed rodent-morphic dosimeters

    PubMed Central

    Bache, Steven T.; Juang, Titania; Belley, Matthew D.; Koontz, Bridget F.; Adamovics, John; Yoshizumi, Terry T.; Kirsch, David G.; Oldham, Mark

    2015-01-01

    Purpose: Sophisticated small animal irradiators, incorporating cone-beam-CT image-guidance, have recently been developed which enable exploration of the efficacy of advanced radiation treatments in the preclinical setting. Microstereotactic-body-radiation-therapy (microSBRT) is one technique of interest, utilizing field sizes in the range of 1–15 mm. Verification of the accuracy of microSBRT treatment delivery is challenging due to the lack of available methods to comprehensively measure dose distributions in representative phantoms with sufficiently high spatial resolution and in 3 dimensions (3D). This work introduces a potential solution in the form of anatomically accurate rodent-morphic 3D dosimeters compatible with ultrahigh resolution (0.3 mm3) optical computed tomography (optical-CT) dose read-out. Methods: Rodent-morphic dosimeters were produced by 3D-printing molds of rodent anatomy directly from contours defined on x-ray CT data sets of rats and mice, and using these molds to create tissue-equivalent radiochromic 3D dosimeters from Presage. Anatomically accurate spines were incorporated into some dosimeters, by first 3D printing the spine mold, then forming a high-Z bone equivalent spine insert. This spine insert was then set inside the tissue equivalent body mold. The high-Z spinal insert enabled representative cone-beam CT IGRT targeting. On irradiation, a linear radiochromic change in optical-density occurs in the dosimeter, which is proportional to absorbed dose, and was read out using optical-CT in high-resolution (0.5 mm isotropic voxels). Optical-CT data were converted to absolute dose in two ways: (i) using a calibration curve derived from other Presage dosimeters from the same batch, and (ii) by independent measurement of calibrated dose at a point using a novel detector comprised of a yttrium oxide based nanocrystalline scintillator, with a submillimeter active length. A microSBRT spinal treatment was delivered consisting of a 180

  15. Investigating the accuracy of microstereotactic-body-radiotherapy utilizing anatomically accurate 3D printed rodent-morphic dosimeters

    SciTech Connect

    Bache, Steven T.; Juang, Titania; Belley, Matthew D.; Koontz, Bridget F.; Yoshizumi, Terry T.; Kirsch, David G.; Oldham, Mark; Adamovics, John

    2015-02-15

    Purpose: Sophisticated small animal irradiators, incorporating cone-beam-CT image-guidance, have recently been developed which enable exploration of the efficacy of advanced radiation treatments in the preclinical setting. Microstereotactic-body-radiation-therapy (microSBRT) is one technique of interest, utilizing field sizes in the range of 1–15 mm. Verification of the accuracy of microSBRT treatment delivery is challenging due to the lack of available methods to comprehensively measure dose distributions in representative phantoms with sufficiently high spatial resolution and in 3 dimensions (3D). This work introduces a potential solution in the form of anatomically accurate rodent-morphic 3D dosimeters compatible with ultrahigh resolution (0.3 mm{sup 3}) optical computed tomography (optical-CT) dose read-out. Methods: Rodent-morphic dosimeters were produced by 3D-printing molds of rodent anatomy directly from contours defined on x-ray CT data sets of rats and mice, and using these molds to create tissue-equivalent radiochromic 3D dosimeters from Presage. Anatomically accurate spines were incorporated into some dosimeters, by first 3D printing the spine mold, then forming a high-Z bone equivalent spine insert. This spine insert was then set inside the tissue equivalent body mold. The high-Z spinal insert enabled representative cone-beam CT IGRT targeting. On irradiation, a linear radiochromic change in optical-density occurs in the dosimeter, which is proportional to absorbed dose, and was read out using optical-CT in high-resolution (0.5 mm isotropic voxels). Optical-CT data were converted to absolute dose in two ways: (i) using a calibration curve derived from other Presage dosimeters from the same batch, and (ii) by independent measurement of calibrated dose at a point using a novel detector comprised of a yttrium oxide based nanocrystalline scintillator, with a submillimeter active length. A microSBRT spinal treatment was delivered consisting of a 180

  16. Accurate 2D/3D electromagnetic modeling for time-domain airborne EM systems

    NASA Astrophysics Data System (ADS)

    Yin, C.; Hodges, G.

    2012-12-01

    The existing industry software cannot deliver correct results for 3D time-domain airborne EM responses. In this paper, starting from the Fourier transform and convolution, we compare the stability of different modeling techniques and analyze the reason for instable calculations of the time-domain airborne EM responses. We find that the singularity of the impulse responses of EM systems at very early time that are used in the convolution is responsible for the instability of the modeling (Fig.1). Based on this finding, we put forward an algorithm that uses step response rather than impulse response of the airborne EM system for the convolution and create a stable algorithm that delivers precise results and maintains well the integral/derivative relationship between the magnetic field B and the magnetic induction dB/dt. A three-step transformation procedure for the modeling is proposed: 1) output the frequency-domain EM response data from the existing software; 2) transform into step-response by digital Fourier/Hankel transform; 3) convolve the step response with the transmitting current or its derivatives. The method has proved to be working very well (Fig. 2). The algorithm can be extended to the modeling of other time-domain ground and airborne EM system responses.Fig. 1: Comparison of impulse and step responses for an airborne EM system Fig. 2: Bz and dBz/dt calculated from step (middle panel) and impulse responses (lower panel) for the same 3D model as in Fig.1.

  17. A New Accurate 3D Measurement Tool to Assess the Range of Motion of the Tongue in Oral Cancer Patients: A Standardized Model.

    PubMed

    van Dijk, Simone; van Alphen, Maarten J A; Jacobi, Irene; Smeele, Ludwig E; van der Heijden, Ferdinand; Balm, Alfons J M

    2016-02-01

    In oral cancer treatment, function loss such as speech and swallowing deterioration can be severe, mostly due to reduced lingual mobility. Until now, there is no standardized measurement tool for tongue mobility and pre-operative prediction of function loss is based on expert opinion instead of evidence based insight. The purpose of this study was to assess the reliability of a triple-camera setup for the measurement of tongue range of motion (ROM) in healthy adults and its feasibility in patients with partial glossectomy. A triple-camera setup was used, and 3D coordinates of the tongue in five standardized tongue positions were achieved in 15 healthy volunteers. Maximum distances between the tip of the tongue and the maxillary midline were calculated. Each participant was recorded twice, and each movie was analysed three times by two separate raters. Intrarater, interrater and test-retest reliability were the main outcome measures. Secondly, feasibility of the method was tested in ten patients treated for oral tongue carcinoma. Intrarater, interrater and test-retest reliability all showed high correlation coefficients of >0.9 in both study groups. All healthy subjects showed perfect symmetrical tongue ROM. In patients, significant differences in lateral tongue movements were found, due to restricted tongue mobility after surgery. This triple-camera setup is a reliable measurement tool to assess three-dimensional information of tongue ROM. It constitutes an accurate tool for objective grading of reduced tongue mobility after partial glossectomy.

  18. Three-dimensional bio-printing.

    PubMed

    Gu, Qi; Hao, Jie; Lu, YangJie; Wang, Liu; Wallace, Gordon G; Zhou, Qi

    2015-05-01

    Three-dimensional (3D) printing technology has been widely used in various manufacturing operations including automotive, defence and space industries. 3D printing has the advantages of personalization, flexibility and high resolution, and is therefore becoming increasingly visible in the high-tech fields. Three-dimensional bio-printing technology also holds promise for future use in medical applications. At present 3D bio-printing is mainly used for simulating and reconstructing some hard tissues or for preparing drug-delivery systems in the medical area. The fabrication of 3D structures with living cells and bioactive moieties spatially distributed throughout will be realisable. Fabrication of complex tissues and organs is still at the exploratory stage. This review summarize the development of 3D bio-printing and its potential in medical applications, as well as discussing the current challenges faced by 3D bio-printing.

  19. A Robust and Accurate Two-Step Auto-Labeling Conditional Iterative Closest Points (TACICP) Algorithm for Three-Dimensional Multi-Modal Carotid Image Registration

    PubMed Central

    Guo, Hengkai; Wang, Guijin; Huang, Lingyun; Hu, Yuxin; Yuan, Chun; Li, Rui; Zhao, Xihai

    2016-01-01

    Atherosclerosis is among the leading causes of death and disability. Combining information from multi-modal vascular images is an effective and efficient way to diagnose and monitor atherosclerosis, in which image registration is a key technique. In this paper a feature-based registration algorithm, Two-step Auto-labeling Conditional Iterative Closed Points (TACICP) algorithm, is proposed to align three-dimensional carotid image datasets from ultrasound (US) and magnetic resonance (MR). Based on 2D segmented contours, a coarse-to-fine strategy is employed with two steps: rigid initialization step and non-rigid refinement step. Conditional Iterative Closest Points (CICP) algorithm is given in rigid initialization step to obtain the robust rigid transformation and label configurations. Then the labels and CICP algorithm with non-rigid thin-plate-spline (TPS) transformation model is introduced to solve non-rigid carotid deformation between different body positions. The results demonstrate that proposed TACICP algorithm has achieved an average registration error of less than 0.2mm with no failure case, which is superior to the state-of-the-art feature-based methods. PMID:26881433

  20. A Robust and Accurate Two-Step Auto-Labeling Conditional Iterative Closest Points (TACICP) Algorithm for Three-Dimensional Multi-Modal Carotid Image Registration.

    PubMed

    Guo, Hengkai; Wang, Guijin; Huang, Lingyun; Hu, Yuxin; Yuan, Chun; Li, Rui; Zhao, Xihai

    2016-01-01

    Atherosclerosis is among the leading causes of death and disability. Combining information from multi-modal vascular images is an effective and efficient way to diagnose and monitor atherosclerosis, in which image registration is a key technique. In this paper a feature-based registration algorithm, Two-step Auto-labeling Conditional Iterative Closed Points (TACICP) algorithm, is proposed to align three-dimensional carotid image datasets from ultrasound (US) and magnetic resonance (MR). Based on 2D segmented contours, a coarse-to-fine strategy is employed with two steps: rigid initialization step and non-rigid refinement step. Conditional Iterative Closest Points (CICP) algorithm is given in rigid initialization step to obtain the robust rigid transformation and label configurations. Then the labels and CICP algorithm with non-rigid thin-plate-spline (TPS) transformation model is introduced to solve non-rigid carotid deformation between different body positions. The results demonstrate that proposed TACICP algorithm has achieved an average registration error of less than 0.2mm with no failure case, which is superior to the state-of-the-art feature-based methods.

  1. Three-dimensional motion measurements using feature tracking.

    PubMed

    Kuo, Johnny; von Ramm, Olaf T

    2008-04-01

    Feature tracking was developed to efficiently compute motion measurements from volumetric ultrasound images. Prior studies have demonstrated the motion magnitude accuracy and computation speed of feature tracking. However, the previous feature tracking implementations were limited by performance of their calculations in rectilinear coordinates. Also, the previous feature tracking approaches did not fully explore the three dimensional (3- D) nature of volumetric image analysis or utilize the 3-D directional information from the tracking calculations. This study presents an improved feature tracking method which achieves further computation speed gains by performing all calculations in the native spherical coordinates of the 3-D ultrasound image. The novel method utilizes a statistical analysis of tracked directions of motion to achieve better rejection of false tracking matches. Results from in vitro tracking of a speckle target show that the new feature tracking method is significantly faster than correlation search and can accurately determine target motion magnitude and 3-D direction.

  2. Three dimensional characterization and archiving system

    SciTech Connect

    Sebastian, R.L.; Clark, R.; Gallman, P.

    1995-10-01

    The Three Dimensional Characterization and Archiving System (3D-ICAS) is being developed as a remote system to perform rapid in situ analysis of hazardous organics and radionuclide contamination on structural materials. Coleman Research and its subcontractors, Thermedics Detection, Inc. (TD) and the University of Idaho (UI) are in the second phase of a three phase program to develop 3D-ICAS to support Decontamination and Decommissioning (D&D) operations. Accurate physical characterization of surfaces and the radioactive and organic is a critical D&D task. Surface characterization includes identification of potentially dangerous inorganic materials, such as asbestos and transite. The 3D-ICAS system robotically conveys a multisensor probe near the surface to be inspected. The sensor position and orientation are monitored and controlled by Coherent laser radar (CLR) tracking. The ICAS fills the need for high speed automated organic analysis by means of gas chromatography-mass spectrometry sensors, and also by radionuclide sensors which combines alpha, beta, and gamma counting.

  3. Ghost particle velocimetry: accurate 3D flow visualization using standard lab equipment.

    PubMed

    Buzzaccaro, Stefano; Secchi, Eleonora; Piazza, Roberto

    2013-07-26

    We describe and test a new approach to particle velocimetry, based on imaging and cross correlating the scattering speckle pattern generated on a near-field plane by flowing tracers with a size far below the diffraction limit, which allows reconstructing the velocity pattern in microfluidic channels without perturbing the flow. As a matter of fact, adding tracers is not even strictly required, provided that the sample displays sufficiently refractive-index fluctuations. For instance, phase separation in liquid mixtures in the presence of shear is suitable to be directly investigated by this "ghost particle velocimetry" technique, which just requires a microscope with standard lamp illumination equipped with a low-cost digital camera. As a further bonus, the peculiar spatial coherence properties of the illuminating source, which displays a finite longitudinal coherence length, allows for a 3D reconstruction of the profile with a resolution of few tenths of microns and makes the technique suitable to investigate turbid samples with negligible multiple scattering effects.

  4. Three-Dimensional Printing in Orthopedic Surgery.

    PubMed

    Eltorai, Adam E M; Nguyen, Eric; Daniels, Alan H

    2015-11-01

    Three-dimensional (3D) printing is emerging as a clinically promising technology for rapid prototyping of surgically implantable products. With this commercially available technology, computed tomography or magnetic resonance images can be used to create graspable objects from 3D reconstructed images. Models can enhance patients' understanding of their pathology and surgeon preoperative planning. Customized implants and casts can be made to match an individual's anatomy. This review outlines 3D printing, its current applications in orthopedics, and promising future directions.

  5. Three Dimensional Migration and Forward Modelling of Ground Penetrating Radar Data.

    DTIC Science & Technology

    1991-06-01

    Unprocessed Data from the Tesi Pit ..................................................................................... 2 FIGURE 3 3D Migrated Data from...acquisition, and inter - pretation are human driven processes. The potential of GPR to generate accurate three dimensional subsurface maps has not...objects or inter - faces occurred. However, the migration operation causes negative reinforcement in the areas where there are no reflections due to

  6. Three dimensional fabrication at small size scales

    PubMed Central

    Leong, Timothy G.; Zarafshar, Aasiyeh M.; Gracias, David H.

    2010-01-01

    Despite the fact that we live in a three-dimensional (3D) world and macroscale engineering is 3D, conventional sub-mm scale engineering is inherently two-dimensional (2D). New fabrication and patterning strategies are needed to enable truly three-dimensionally-engineered structures at small size scales. Here, we review strategies that have been developed over the last two decades that seek to enable such millimeter to nanoscale 3D fabrication and patterning. A focus of this review is the strategy of self-assembly, specifically in a biologically inspired, more deterministic form known as self-folding. Self-folding methods can leverage the strengths of lithography to enable the construction of precisely patterned 3D structures and “smart” components. This self-assembling approach is compared with other 3D fabrication paradigms, and its advantages and disadvantages are discussed. PMID:20349446

  7. Accurate gradient approximation for complex interface problems in 3D by an improved coupling interface method

    SciTech Connect

    Shu, Yu-Chen; Chern, I-Liang; Chang, Chien C.

    2014-10-15

    Most elliptic interface solvers become complicated for complex interface problems at those “exceptional points” where there are not enough neighboring interior points for high order interpolation. Such complication increases especially in three dimensions. Usually, the solvers are thus reduced to low order accuracy. In this paper, we classify these exceptional points and propose two recipes to maintain order of accuracy there, aiming at improving the previous coupling interface method [26]. Yet the idea is also applicable to other interface solvers. The main idea is to have at least first order approximations for second order derivatives at those exceptional points. Recipe 1 is to use the finite difference approximation for the second order derivatives at a nearby interior grid point, whenever this is possible. Recipe 2 is to flip domain signatures and introduce a ghost state so that a second-order method can be applied. This ghost state is a smooth extension of the solution at the exceptional point from the other side of the interface. The original state is recovered by a post-processing using nearby states and jump conditions. The choice of recipes is determined by a classification scheme of the exceptional points. The method renders the solution and its gradient uniformly second-order accurate in the entire computed domain. Numerical examples are provided to illustrate the second order accuracy of the presently proposed method in approximating the gradients of the original states for some complex interfaces which we had tested previous in two and three dimensions, and a real molecule ( (1D63)) which is double-helix shape and composed of hundreds of atoms.

  8. Single-arc volumetric-modulated arc therapy (sVMAT) as adjuvant treatment for gastric cancer: Dosimetric comparisons with three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT)

    SciTech Connect

    Wang, Xin; Li, Guangjun; Zhang, Yingjie; Bai, Sen; Xu, Feng; Wei, Yuquan; Gong, Youling

    2013-01-01

    To compare the dosimetric differences between the single-arc volumetric-modulated arc therapy (sVMAT), 3-dimensional conformal radiotherapy (3D-CRT), and intensity-modulated radiotherapy (IMRT) techniques in treatment planning for gastric cancer as adjuvant radiotherapy. Twelve patients were retrospectively analyzed. In each patient's case, the parameters were compared based on the dose-volume histogram (DVH) of the sVMAT, 3D-CRT, and IMRT plans, respectively. Three techniques showed similar target dose coverage. The maximum and mean doses of the target were significantly higher in the sVMAT plans than that in 3D-CRT plans and in the 3D-CRT/IMRT plans, respectively, but these differences were clinically acceptable. The IMRT and sVMAT plans successfully achieved better target dose conformity, reduced the V{sub 20/30}, and mean dose of the left kidney, as well as the V{sub 20/30} of the liver, compared with the 3D-CRT plans. And the sVMAT technique reduced the V{sub 20} of the liver much significantly. Although the maximum dose of the spinal cord were much higher in the IMRT and sVMAT plans, respectively (mean 36.4 vs 39.5 and 40.6 Gy), these data were still under the constraints. Not much difference was found in the analysis of the parameters of the right kidney, intestine, and heart. The IMRT and sVMAT plans achieved similar dose distribution to the target, but superior to the 3D-CRT plans, in adjuvant radiotherapy for gastric cancer. The sVMAT technique improved the dose sparings of the left kidney and liver, compared with the 3D-CRT technique, but showed few dosimetric advantages over the IMRT technique. Studies are warranted to evaluate the clinical benefits of the VMAT treatment for patients with gastric cancer after surgery in the future.

  9. Three-dimensional colloidal lithography.

    PubMed

    Nagai, Hironori; Poteet, Austen; Zhang, Xu A; Chang, Chih-Hao

    2017-03-24

    Light interactions with colloidal particles can generate a variety of complex three-dimensional (3D) intensity patterns, which can be utilized for nanolithography. The study of particle-light interactions can add more types of intensity patterns by manipulating key factors. Here we investigate a novel 3D nanolithography technique using colloidal particles under two-beam coherent illuminations. The fabricated 3D nanostructures are hollow, nested within periodic structures, and possess multiple chamber geometry. The effects of incident angles and particle size on the fabricated nanostructures were examined. The relative phase shift between particle position and interference pattern is identified as another significant parameter influencing the resultant nanostructures. A numerical model has been developed to show the evolution of nanostructure geometry with phase shifts, and experimental studies confirm the simulation results. Through the introduction of single colloidal particles, the fabrication capability of Lloyd's mirror interference can now be extended to fabrication of 3D nanostructure with complex shell geometry. The fabricated hollow nanostructures with grating background could find potential applications in the area of photonics, drug delivery, and nanofluidics.

  10. Three-dimensional colloidal lithography

    NASA Astrophysics Data System (ADS)

    Nagai, Hironori; Poteet, Austen; Zhang, Xu A.; Chang, Chih-Hao

    2017-03-01

    Light interactions with colloidal particles can generate a variety of complex three-dimensional (3D) intensity patterns, which can be utilized for nanolithography. The study of particle–light interactions can add more types of intensity patterns by manipulating key factors. Here we investigate a novel 3D nanolithography technique using colloidal particles under two-beam coherent illuminations. The fabricated 3D nanostructures are hollow, nested within periodic structures, and possess multiple chamber geometry. The effects of incident angles and particle size on the fabricated nanostructures were examined. The relative phase shift between particle position and interference pattern is identified as another significant parameter influencing the resultant nanostructures. A numerical model has been developed to show the evolution of nanostructure geometry with phase shifts, and experimental studies confirm the simulation results. Through the introduction of single colloidal particles, the fabrication capability of Lloyd’s mirror interference can now be extended to fabrication of 3D nanostructure with complex shell geometry. The fabricated hollow nanostructures with grating background could find potential applications in the area of photonics, drug delivery, and nanofluidics.

  11. Freehand three-dimensional ultrasound to assess semitendinosus muscle morphology.

    PubMed

    Haberfehlner, Helga; Maas, Huub; Harlaar, Jaap; Becher, Jules G; Buizer, Annemieke I; Jaspers, Richard T

    2016-10-01

    In several neurological disorders and muscle injuries, morphological changes of the m. semitendinosus (ST) are presumed to contribute to movement limitations around the knee. Freehand three-dimensional (3D) ultrasound (US), using position tracking of two-dimensional US images to reconstruct a 3D voxel array, can be used to assess muscle morphology in vivo. The aims of this study were: (i) to introduce a newly developed 3D US protocol for ST; and (ii) provide a first comparison of morphological characteristics determined by 3D US with those measured on dissected cadaveric muscles. Morphological characteristics of ST (e.g. muscle belly length, tendon length, fascicle length and whole muscle volume, and volumes of both compartments) were assessed in six cadavers using a 3D US protocol. Subsequently, ST muscles were removed from the body to measure the same morphological characteristics. Mean differences between morphological characteristics measured by 3D US and after dissection were smaller than 10%. Intra-class correlation coefficients (ICCs) were higher than 0.75 for all variables except for the lengths of proximal fascicles (ICC = 0.58). Measurement of the volume of proximal compartment by 3D US was not feasible, due to low US image quality proximally. We conclude that the presented 3D US protocol allows for reasonably accurate measurements of key morphological characteristics of ST muscle.

  12. Fast, Accurate and Precise Mid-Sagittal Plane Location in 3D MR Images of the Brain

    NASA Astrophysics Data System (ADS)

    Bergo, Felipe P. G.; Falcão, Alexandre X.; Yasuda, Clarissa L.; Ruppert, Guilherme C. S.

    Extraction of the mid-sagittal plane (MSP) is a key step for brain image registration and asymmetry analysis. We present a fast MSP extraction method for 3D MR images, based on automatic segmentation of the brain and on heuristic maximization of the cerebro-spinal fluid within the MSP. The method is robust to severe anatomical asymmetries between the hemispheres, caused by surgical procedures and lesions. The method is also accurate with respect to MSP delineations done by a specialist. The method was evaluated on 64 MR images (36 pathological, 20 healthy, 8 synthetic), and it found a precise and accurate approximation of the MSP in all of them with a mean time of 60.0 seconds per image, mean angular variation within a same image (precision) of 1.26o and mean angular difference from specialist delineations (accuracy) of 1.64o.

  13. Three-dimensional mapping of soil chemical characteristics at micrometric scale: Statistical prediction by combining 2D SEM-EDX data and 3D X-ray computed micro-tomographic images

    NASA Astrophysics Data System (ADS)

    Hapca, Simona

    2015-04-01

    Many soil properties and functions emerge from interactions of physical, chemical and biological processes at microscopic scales, which can be understood only by integrating techniques that traditionally are developed within separate disciplines. While recent advances in imaging techniques, such as X-ray computed tomography (X-ray CT), offer the possibility to reconstruct the 3D physical structure at fine resolutions, for the distribution of chemicals in soil, existing methods, based on scanning electron microscope (SEM) and energy dispersive X-ray detection (EDX), allow for characterization of the chemical composition only on 2D surfaces. At present, direct 3D measurement techniques are still lacking, sequential sectioning of soils, followed by 2D mapping of chemical elements and interpolation to 3D, being an alternative which is explored in this study. Specifically, we develop an integrated experimental and theoretical framework which combines 3D X-ray CT imaging technique with 2D SEM-EDX and use spatial statistics methods to map the chemical composition of soil in 3D. The procedure involves three stages 1) scanning a resin impregnated soil cube by X-ray CT, followed by precision cutting to produce parallel thin slices, the surfaces of which are scanned by SEM-EDX, 2) alignment of the 2D chemical maps within the internal 3D structure of the soil cube, and 3) development, of spatial statistics methods to predict the chemical composition of 3D soil based on the observed 2D chemical and 3D physical data. Specifically, three statistical models consisting of a regression tree, a regression tree kriging and cokriging model were used to predict the 3D spatial distribution of carbon, silicon, iron and oxygen in soil, these chemical elements showing a good spatial agreement between the X-ray grayscale intensities and the corresponding 2D SEM-EDX data. Due to the spatial correlation between the physical and chemical data, the regression-tree model showed a great potential

  14. Performing Accurate Rigid Kinematics Measurements from 3D in vivo Image Sequences through Median Consensus Simultaneous Registration.

    PubMed

    Cresson, T; Jacq, J; Burdin, V; Roux, Ch

    2005-01-01

    While focusing at accurate 3D joint kinematics, this paper explores the problem of how to perform a robust rigid registration for a sequence of object surfaces observed using standard 3D medical imaging techniques. Each object instance is assumed to give access to a polyhedral encoding of its boundary. We consider the case where object instances are noised with significant truncations and segmentation errors. The proposed method aims to tackle this problem in a global way, fully exploiting the duality between redundancy and complementarity of the available instances set. The algorithm operates through robust and simultaneous registration of all geometrical instances on a virtual instance accounting for their median consensus. When compared with standard robust techniques, trials reveal significant gains, as much in robustness as in accuracy. The considered applications are mainly focused on generating highly accurate kinematics in relation to the bone structures of the most complex joints - the tarsus and the carpus - for which no alternative examination techniques exist, enabling fine morphological analysis as well as access to internal joint motions.

  15. Three dimensional characterization and archiving system

    SciTech Connect

    Sebastian, R.L.; Clark, R.; Gallman, P.

    1995-12-01

    The Three Dimensional Characterization and Archiving System (3D-ICAS) is being developed as a remote system to perform rapid in situ analysis of hazardous organics and radionuclide contamination on structural materials. Coleman Research and its subcontractors, Thermedics Detection, Inc. (TD) and the University of Idaho (UI) are in the second phase of a three phase program to develop 3D-ICAS to support Decontamination and Decommissioning (D&D) operations. Accurate physical characterization of surfaces and the radioactive and organic is a critical D&D task. Surface characterization includes identification of potentially dangerous inorganic materials, such as asbestos and transite. Real-time remotely operable characterization instrumentation will significantly advance the analysis capabilities beyond those currently employed. Chemical analysis is a primary area where the characterization process will be improved. Chemical analysis plays a vital role throughout the process of decontamination. Before clean-up operations can begin the site must be characterized with respect to the type and concentration of contaminants, and detailed site mapping must clarify areas of both high and low risk. During remediation activities chemical analysis provides a means to measure progress and to adjust clean-up strategy. Once the clean-up process has been completed the results of chemical analysis will verify that the site is in compliance with federal and local regulations.

  16. A New Three-Dimensional Cephalometric Analysis for Orthognathic Surgery

    PubMed Central

    Gateno, Jaime; Xia, James J.; Teichgraeber, John F.

    2010-01-01

    Two basic problems are associated with traditional 2-dimensional ((2D) cephalometry First, many important parameters cannot be measured on plain cephalograms; and second, most 2D cephalometric measurements are distorted in the presence of facial asymmetry. Three-dimensional (3D) cephalometry, which has been facilitated by the introduction of cone beam computed tomography scans, can be solved these problems. However, before this can be realized, fundamental problems must be solved. They are the unreliability of internal reference systems and some 3D measurements, and the lack of tools to assess and measure symmetry. In this manuscript, the authors present a new 3D cephalometric analysis that uses different geometric approaches to solve the fundamental problems previously mentioned. This analysis allows the accurate measurement of the size, shape, position and orientation of the different facial units and incorporates a novel method to measure asymmetry. PMID:21257250

  17. Isotropic three-dimensional MRI-Fricke-infused gel dosimetry

    SciTech Connect

    Cho, Nai-Yu; Chu, Woei-Chyn; Huang, Sung-Cheng; Chung, Wen-Yuh; Guo, Wan-Yuo

    2013-05-15

    Purpose: Fricke-infused gel has been shown to be a simple and attainable method for the conformal measurement of absorbed radiation dose. Nevertheless, its accuracy is seriously hindered by the irreversible ferric ion diffusion during magnetic resonance imaging, particularly when three-dimensional (3D) dose measurement in radiosurgery is considered. In this study, the authors developed a fast three-dimensional spin-echo based Fricke gel dosimetry technique to reduce the adverse effects of ferric ion diffusion and to obtain an accurate isotropic 3D dose measurement. Methods: A skull shaped phantom containing Fricke-infused gel was irradiated using Leksell Gamma Knife. The rapid image-based dosimetry technique was applied with the use of a 3D fast spin-echo magnetic resonance imaging sequence. The authors mathematically derived and experimentally validated the correlations between dose-response characteristics and parameters of the 3D fast spin-echo MR imaging sequence. Absorbed dose profiles were assessed and compared to the calculated profiles given by the Gamma Knife treatment planning system. Coefficient of variance (CV%) and coefficient of determination (R{sup 2}) were used to evaluate the precision of dose-response curve estimation. The agreement between the measured and the planned 3D dose distributions was quantified by gamma-index analysis of two acceptance criteria. Results: Proper magnetic resonance imaging parameters were explored to render an accurate three-dimensional absorbed dose mapping with a 1 mm{sup 3} isotropic image resolution. The efficacy of the dose-response estimation was approved by an R{sup 2} > 0.99 and an average CV% of 1.6%. Average gamma pass-rate between the experimentally measured and GammaPlan calculated dose distributions were 83.8% and 99.7% for 2%/2 and 3%/3 mm criteria, respectively. Conclusions: With the designed MR imaging sequence and parameters, total 3D MR acquisition time was confined to within 20 min postirradiation

  18. Lossless compression for three-dimensional images

    NASA Astrophysics Data System (ADS)

    Tang, Xiaoli; Pearlman, William A.

    2004-01-01

    We investigate and compare the performance of several three-dimensional (3D) embedded wavelet algorithms on lossless 3D image compression. The algorithms are Asymmetric Tree Three-Dimensional Set Partitioning In Hierarchical Trees (AT-3DSPIHT), Three-Dimensional Set Partitioned Embedded bloCK (3D-SPECK), Three-Dimensional Context-Based Embedded Zerotrees of Wavelet coefficients (3D-CB-EZW), and JPEG2000 Part II for multi-component images. Two kinds of images are investigated in our study -- 8-bit CT and MR medical images and 16-bit AVIRIS hyperspectral images. First, the performances by using different size of coding units are compared. It shows that increasing the size of coding unit improves the performance somewhat. Second, the performances by using different integer wavelet transforms are compared for AT-3DSPIHT, 3D-SPECK and 3D-CB-EZW. None of the considered filters always performs the best for all data sets and algorithms. At last, we compare the different lossless compression algorithms by applying integer wavelet transform on the entire image volumes. For 8-bit medical image volumes, AT-3DSPIHT performs the best almost all the time, achieving average of 12% decreases in file size compared with JPEG2000 multi-component, the second performer. For 16-bit hyperspectral images, AT-3DSPIHT always performs the best, yielding average 5.8% and 8.9% decreases in file size compared with 3D-SPECK and JPEG2000 multi-component, respectively. Two 2D compression algorithms, JPEG2000 and UNIX zip, are also included for reference, and all 3D algorithms perform much better than 2D algorithms.

  19. Three-Dimensional Shallow Water Acoustics

    DTIC Science & Technology

    2015-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Three-Dimensional Shallow Water Acoustics Dr. Ying...model to predict acoustic fluctuations and derive sound pressure sensitivity kernels due to 3-D sound speed perturbation in the water column. The...numerical method to be utilized is a tangent linear solution to predict acoustic fluctuations due to 3-D sound speed perturbation in the water column. This

  20. Analysis and visualization of complex unsteady three-dimensional flows

    NASA Technical Reports Server (NTRS)

    Van Dalsem, William R.; Buning, Pieter G.; Dougherty, F. Carroll; Smith, Merritt H.

    1989-01-01

    Flow field animation is the natural choice as a tool in the analysis of the numerical simulations of complex unsteady three-dimensional flows. The PLOT4D extension of the widely used PLOT3D code to allow the interactive animation of a broad range of flow variables was developed and is presented. To allow direct comparison with unsteady experimental smoke and dye flow visualization, the code STREAKER was developed to produce time accurate streaklines. Considerations regarding the development of PLOT4D and STREAKER, and example results are presented.

  1. Three-Dimensional Magnetohydrodynamic Simulation of Slapper Initiation Systems

    SciTech Connect

    Christensen, J S; Hrousis, C A

    2010-03-09

    Although useful information can be gleaned from 2D and even 1D simulations of slapper type initiation systems, these systems are inherently three-dimensional and therefore require full 3D representation to model all relevant details. Further, such representation provides additional insight into optimizing the design of such devices from a first-principles perspective and can thereby reduce experimental costs. We discuss in this paper several ongoing efforts in modeling these systems, our pursuit of validation, and extension of these methods to other systems. Our results show the substantial dependence upon highly accurate global equations of state and resistivity models in these analyses.

  2. Three dimensional single molecule localization using a phase retrieved pupilfunction

    PubMed Central

    Liu, Sheng; Kromann, Emil B.; Krueger, Wesley D.; Bewersdorf, Joerg; Lidke, Keith A.

    2013-01-01

    Localization-based superresolution imaging is dependent on finding the positions of individualfluorophores in a sample by fitting the observed single-molecule intensity pattern to the microscopepoint spread function (PSF). For three-dimensional imaging, system-specific aberrations of theoptical system can lead to inaccurate localizations when the PSF model does not account for theseaberrations. Here we describe the use of phase-retrieved pupil functions to generate a more accuratePSF and therefore more accurate 3D localizations. The complex-valued pupil function containsinformation about the system-specific aberrations and can thus be used to generate the PSF forarbitrary defocus. Further, it can be modified to include depth dependent aberrations. We describethe phase retrieval process, the method for including depth dependent aberrations, and a fastfitting algorithm using graphics processing units. The superior localization accuracy of the pupilfunction generated PSF is demonstrated with dual focal plane 3D superresolution imaging ofbiological structures. PMID:24514501

  3. Three-dimensional aromatic networks.

    PubMed

    Toyota, Shinji; Iwanaga, Tetsuo

    2014-01-01

    Three-dimensional (3D) networks consisting of aromatic units and linkers are reviewed from various aspects. To understand principles for the construction of such compounds, we generalize the roles of building units, the synthetic approaches, and the classification of networks. As fundamental compounds, cyclophanes with large aromatic units and aromatic macrocycles with linear acetylene linkers are highlighted in terms of transannular interactions between aromatic units, conformational preference, and resolution of chiral derivatives. Polycyclic cage compounds are constructed from building units by linkages via covalent bonds, metal-coordination bonds, or hydrogen bonds. Large cage networks often include a wide range of guest species in their cavity to afford novel inclusion compounds. Topological isomers consisting of two or more macrocycles are formed by cyclization of preorganized species. Some complicated topological networks are constructed by self-assembly of simple building units.

  4. Three-dimensional metamaterials

    SciTech Connect

    Burckel, David Bruce

    2012-06-12

    A fabrication method is capable of creating canonical metamaterial structures arrayed in a three-dimensional geometry. The method uses a membrane suspended over a cavity with predefined pattern as a directional evaporation mask. Metallic and/or dielectric material can be evaporated at high vacuum through the patterned membrane to deposit resonator structures on the interior walls of the cavity, thereby providing a unit cell of micron-scale dimension. The method can produce volumetric metamaterial structures comprising layers of such unit cells of resonator structures.

  5. Three dimensional quantum chromodynamics

    NASA Astrophysics Data System (ADS)

    Ferretti, G.; Rajeev, S. G.; Yang, Z.

    1992-02-01

    The subject of this talk is the study of the low energy behavior of three (2+1) dimensional Quantum Chromodynamics. We show the existence of a phase where parity is unbroken and the flavor group U(2n) is broken into a subgroup U(n)×U(n). We derive the low energy effective action for the theory and show that it has solitonic excitations with Fermi statistic, to be identified with the three dimensional ``baryon''. Finally, we study the current algebra for this effective action and we find a co-homologically nontrivial generalization of Kac-Moody algebras to three dimension.

  6. The Effect of Flattening Filter Free on Three-dimensional Conformal Radiation Therapy (3D-CRT), Intensity-Modulated Radiation Therapy (IMRT), and Volumetric Modulated Arc Therapy (VMAT) Plans for Metastatic Brain Tumors from Non-small Cell Lung Cancer.

    PubMed

    Shi, Li-Wan; Lai, You-Qun; Lin, Qin; Ha, Hui-Ming; Fu, Li-Rong

    2015-07-01

    Flattening filter free (FFF) may affect outcome measures of radiotherapy. The objective of this study is to compare the dosimetric parameters in three types of radiotherapy plans, three-dimensional conformal radiation therapy (3D-CRT), intensity-modulated radiation therapy (IMRT), and volumetric modulated arc therapy (VMAT), with or without the flattening filter (FF), developed for the treatment of metastatic brain tumors from non-small cell lung cancer (NSCLC). From July 2013 to October 2013, 3D-CRT, IMRT, and VMAT treatment plans were designed using 6 MV and 10 MV, with and without FF, for 10 patients with brain metastasis from NSCLC. The evaluation of the treatment plans included homogeneity index (HI), conformity index (CI), monitor units (MU), mean dose (Dmean), treatment time, and the influence of FFF on volumes. There was no difference in CI or HI between FFF and FF models with 3D-CRT, IMRT, and VMAT plans. At 6 MV, a lower Dmean was seen in the FFF model of 3D-CRT and in the VMAT plan at 10 MV. In the IMRT 6 MV, IMRT 10 MV, and VMAT 10 MV plans, higher MUs were seen in the FFF models. FFF treatments are similar in quality to FF plans, generally lead to more monitor units, and are associated with shorter treatment times. FFF plans ranked by the order of superiority in terms of a time advantage are VMAT, 3D-CRT, and IMRT.

  7. Three Dimensional Dirac Semimetals

    NASA Astrophysics Data System (ADS)

    Zaheer, Saad

    2014-03-01

    Dirac points on the Fermi surface of two dimensional graphene are responsible for its unique electronic behavior. One can ask whether any three dimensional materials support similar pseudorelativistic physics in their bulk electronic spectra. This possibility has been investigated theoretically and is now supported by two successful experimental demonstrations reported during the last year. In this talk, I will summarize the various ways in which Dirac semimetals can be realized in three dimensions with primary focus on a specific theory developed on the basis of representations of crystal spacegroups. A three dimensional Dirac (Weyl) semimetal can appear in the presence (absence) of inversion symmetry by tuning parameters to the phase boundary separating a bulk insulating and a topological insulating phase. More generally, we find that specific rules governing crystal symmetry representations of electrons with spin lead to robust Dirac points at high symmetry points in the Brillouin zone. Combining these rules with microscopic considerations identifies six candidate Dirac semimetals. Another method towards engineering Dirac semimetals involves combining crystal symmetry and band inversion. Several candidate materials have been proposed utilizing this mechanism and one of the candidates has been successfully demonstrated as a Dirac semimetal in two independent experiments. Work carried out in collaboration with: Julia A. Steinberg, Steve M. Young, J.C.Y. Teo, C.L. Kane, E.J. Mele and Andrew M. Rappe.

  8. Three-dimensional hologram display system

    NASA Technical Reports Server (NTRS)

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

    2009-01-01

    The present invention relates to a three-dimensional (3D) hologram display system. The 3D hologram display system includes a projector device for projecting an image upon a display medium to form a 3D hologram. The 3D hologram is formed such that a viewer can view the holographic image from multiple angles up to 360 degrees. Multiple display media are described, namely a spinning diffusive screen, a circular diffuser screen, and an aerogel. The spinning diffusive screen utilizes spatial light modulators to control the image such that the 3D image is displayed on the rotating screen in a time-multiplexing manner. The circular diffuser screen includes multiple, simultaneously-operated projectors to project the image onto the circular diffuser screen from a plurality of locations, thereby forming the 3D image. The aerogel can use the projection device described as applicable to either the spinning diffusive screen or the circular diffuser screen.

  9. Fabrication of three dimensional microstructure fiber

    NASA Astrophysics Data System (ADS)

    Luo, Ying; Ma, Jie; Chen, Zhe; Lu, Huihui; Zhong, Yongchun

    2015-05-01

    A method of fabricating three dimensional (3D) microstructured fiber is presented. Polystyrene (PS) microspheres were coated around the surface of a micro-fiber through isothermal heating evaporation induced self-assembly method. Scanning electron microscopy (SEM) image shows that the colloidal crystal has continuous, uniform, and well-ordered face-centered cubic (FCC) structure, with [111] crystallographic direction normal to the surface of micro-fiber. This micro-fiber with three-dimensional photonic crystals structure is very useful in the applications of micro-fiber sensors or filters.

  10. Frozen Gaussian approximation for three-dimensional seismic wave propagation

    NASA Astrophysics Data System (ADS)

    Chai, Lihui; Tong, Ping; Yang, Xu

    2016-09-01

    We present a systematic introduction on applying frozen Gaussian approximation (FGA) to compute synthetic seismograms in three-dimensional earth models. In this method, seismic wavefield is decomposed into frozen (fixed-width) Gaussian functions, which propagate along ray paths. Rather than the coherent state solution to the wave equation, this method is rigorously derived by asymptotic expansion on phase plane, with analysis of its accuracy determined by the ratio of short wavelength over large domain size. Similar to other ray-based beam methods (e.g. Gaussian beam methods), one can use relatively small number of Gaussians to get accurate approximations of high-frequency wavefield. The algorithm is embarrassingly parallel, which can drastically speed up the computation with a multicore-processor computer station. We illustrate the accuracy and efficiency of the method by comparing it to the spectral element method for a three-dimensional (3D) seismic wave propagation in homogeneous media, where one has the analytical solution as a benchmark. As another proof of methodology, simulations of high-frequency seismic wave propagation in heterogeneous media are performed for 3D waveguide model and smoothed Marmousi model respectively. The second contribution of this paper is that, we incorporate the Snell's law into the FGA formulation, and asymptotically derive reflection, transmission and free surface conditions for FGA to compute high-frequency seismic wave propagation in high contrast media. We numerically test these conditions by computing traveltime kernels of different phases in the 3D crust-over-mantle model.

  11. Three-dimensional laser microvision.

    PubMed

    Shimotahira, H; Iizuka, K; Chu, S C; Wah, C; Costen, F; Yoshikuni, Y

    2001-04-10

    A three-dimensional (3-D) optical imaging system offering high resolution in all three dimensions, requiring minimum manipulation and capable of real-time operation, is presented. The system derives its capabilities from use of the superstructure grating laser source in the implementation of a laser step frequency radar for depth information acquisition. A synthetic aperture radar technique was also used to further enhance its lateral resolution as well as extend the depth of focus. High-speed operation was made possible by a dual computer system consisting of a host and a remote microcomputer supported by a dual-channel Small Computer System Interface parallel data transfer system. The system is capable of operating near real time. The 3-D display of a tunneling diode, a microwave integrated circuit, and a see-through image taken by the system operating near real time are included. The depth resolution is 40 mum; lateral resolution with a synthetic aperture approach is a fraction of a micrometer and that without it is approximately 10 mum.

  12. Three-Dimensional Laser Microvision

    NASA Astrophysics Data System (ADS)

    Shimotahira, Hiroshi; Iizuka, Keigo; Chu, Sun-Chun; Wah, Christopher; Costen, Furnie; Yoshikuni, Yuzo

    2001-04-01

    A three-dimensional (3-D) optical imaging system offering high resolution in all three dimensions, requiring minimum manipulation and capable of real-time operation, is presented. The system derives its capabilities from use of the superstructure grating laser source in the implementation of a laser step frequency radar for depth information acquisition. A synthetic aperture radar technique was also used to further enhance its lateral resolution as well as extend the depth of focus. High-speed operation was made possible by a dual computer system consisting of a host and a remote microcomputer supported by a dual-channel Small Computer System Interface parallel data transfer system. The system is capable of operating near real time. The 3-D display of a tunneling diode, a microwave integrated circuit, and a see-through image taken by the system operating near real time are included. The depth resolution is 40 m; lateral resolution with a synthetic aperture approach is a fraction of a micrometer and that without it is approximately 10 m.

  13. Fast and accurate 3-D ray tracing using bilinear traveltime interpolation and the wave front group marching

    NASA Astrophysics Data System (ADS)

    Zhang, Jianzhong; Huang, Yueqin; Song, Lin-Ping; Liu, Qing-Huo

    2011-03-01

    We propose a new ray tracing technique in a 3-D heterogeneous isotropic media based on bilinear traveltime interpolation and the wave front group marching. In this technique, the media is discretized into a series of rectangular cells. There are two steps to be carried out: one is a forward step where wave front expansion is evolved from sources to whole computational domain and the subsequent one is a backward step where ray paths are calculated for any source-receiver configuration as desired. In the forward step, we derive a closed-form expression to calculate traveltime at an arbitrary point in a cell using a bilinear interpolation of the known traveltimes on the cell's surface. Then the group marching method (GMM), a fast wave front advancing method, is applied to expand the wave front from the source to all girds. In the backward step, ray paths starting from receivers are traced by finding the intersection points of potential ray propagation vectors with the surfaces of relevant cells. In this step, the same TI scheme is used to compute the candidate intersection points on all surfaces of each relevant cell. In this process, the point with the minimum traveltime is selected as a ray point from which the similar step is continued until sources. A number of numerical experiments demonstrate that our 3-D ray tracing technique is able to achieve very accurate computation of traveltimes and ray paths and meanwhile take much less computer time in comparison with the existing popular ones like the finite-difference-based GMM method, which is combined with the maximum gradient ray tracing, and the shortest path method.

  14. Assessment of left ventricular function by three-dimensional echocardiography

    PubMed Central

    Krenning, Boudewijn J; Voormolen, Marco M; Roelandt, Jos RTC

    2003-01-01

    Accurate determination of LV volume, ejection fraction and segmental wall motion abnormalities is important for clinical decision-making and follow-up assessment. Currently, echocardiography is the most common used method to obtain this information. Three-dimensional echocardiography has shown to be an accurate and reproducible method for LV quantitation, mainly by avoiding the use of geometric assumptions. In this review, we describe various methods to acquire a 3D-dataset for LV volume and wall motion analysis, including their advantages and limitations. We provide an overview of studies comparing LV volume and function measurement by various gated and real-time methods of acquisition compared to magnetic resonance imaging. New technical improvements, such as automated endocardial border detection and contrast enhancement, will make accurate on-line assessment with little operator interaction possible in the near future. PMID:14514356

  15. Dual-domain denoising in three dimensional magnetic resonance imaging.

    PubMed

    Peng, Jing; Zhou, Jiliu; Wu, Xi

    2016-08-01

    Denoising is a crucial preprocessing procedure for three dimensional magnetic resonance imaging (3D MRI). Existing denoising methods are predominantly implemented in a single domain, ignoring information in other domains. However, denoising methods are becoming increasingly complex, making analysis and implementation challenging. The present study aimed to develop a dual-domain image denoising (DDID) algorithm for 3D MRI that encapsulates information from the spatial and transform domains. In the present study, the DDID method was used to distinguish signal from noise in the spatial and frequency domains, after which robust accurate noise estimation was introduced for iterative filtering, which is simple and beneficial for computation. In addition, the proposed method was compared quantitatively and qualitatively with existing methods for synthetic and in vivo MRI datasets. The results of the present study suggested that the novel DDID algorithm performed well and provided competitive results, as compared with existing MRI denoising filters.

  16. Three-Dimensional Complex Variables

    NASA Technical Reports Server (NTRS)

    Martin, E. Dale

    1988-01-01

    Report presents new theory of analytic functions of three-dimensional complex variables. While three-dimensional system subject to more limitations and more difficult to use than the two-dimensional system, useful in analysis of three-dimensional fluid flows, electrostatic potentials, and other phenomena involving harmonic functions.

  17. Accurate first-principles calculations for 12CH3D infrared spectra from isotopic and symmetry transformations

    NASA Astrophysics Data System (ADS)

    Rey, Michaël; Nikitin, Andrei V.; Tyuterev, Vladimir G.

    2014-07-01

    Accurate variational high-resolution spectra calculations in the range 0-8000 cm-1 are reported for the first time for the monodeutered methane (12CH3D). Global calculations were performed by using recent ab initio surfaces for line positions and line intensities derived from the main isotopologue 12CH4. Calculation of excited vibrational levels and high-J rovibrational states is described by using the normal mode Eckart-Watson Hamiltonian combined with irreducible tensor formalism and appropriate numerical procedures for solving the quantum nuclear motion problem. The isotopic H→D substitution is studied in details by means of symmetry and nonlinear normal mode coordinate transformations. Theoretical spectra predictions are given up to J = 25 and compared with the HITRAN 2012 database representing a compilation of line lists derived from analyses of experimental spectra. The results are in very good agreement with available empirical data suggesting that a large number of yet unassigned lines in observed spectra could be identified and modeled using the present approach.

  18. A fast experimental beam hardening correction method for accurate bone mineral measurements in 3D μCT imaging system.

    PubMed

    Koubar, Khodor; Bekaert, Virgile; Brasse, David; Laquerriere, Patrice

    2015-06-01

    Bone mineral density plays an important role in the determination of bone strength and fracture risks. Consequently, it is very important to obtain accurate bone mineral density measurements. The microcomputerized tomography system provides 3D information about the architectural properties of bone. Quantitative analysis accuracy is decreased by the presence of artefacts in the reconstructed images, mainly due to beam hardening artefacts (such as cupping artefacts). In this paper, we introduced a new beam hardening correction method based on a postreconstruction technique performed with the use of off-line water and bone linearization curves experimentally calculated aiming to take into account the nonhomogeneity in the scanned animal. In order to evaluate the mass correction rate, calibration line has been carried out to convert the reconstructed linear attenuation coefficient into bone masses. The presented correction method was then applied on a multimaterial cylindrical phantom and on mouse skeleton images. Mass correction rate up to 18% between uncorrected and corrected images were obtained as well as a remarkable improvement of a calculated mouse femur mass has been noticed. Results were also compared to those obtained when using the simple water linearization technique which does not take into account the nonhomogeneity in the object.

  19. Accurate first-principles calculations for 12CH3D infrared spectra from isotopic and symmetry transformations.

    PubMed

    Rey, Michaël; Nikitin, Andrei V; Tyuterev, Vladimir G

    2014-07-28

    Accurate variational high-resolution spectra calculations in the range 0-8000 cm(-1) are reported for the first time for the monodeutered methane ((12)CH3D). Global calculations were performed by using recent ab initio surfaces for line positions and line intensities derived from the main isotopologue (12)CH4. Calculation of excited vibrational levels and high-J rovibrational states is described by using the normal mode Eckart-Watson Hamiltonian combined with irreducible tensor formalism and appropriate numerical procedures for solving the quantum nuclear motion problem. The isotopic H→D substitution is studied in details by means of symmetry and nonlinear normal mode coordinate transformations. Theoretical spectra predictions are given up to J = 25 and compared with the HITRAN 2012 database representing a compilation of line lists derived from analyses of experimental spectra. The results are in very good agreement with available empirical data suggesting that a large number of yet unassigned lines in observed spectra could be identified and modeled using the present approach.

  20. Accurate first-principles calculations for {sup 12}CH{sub 3}D infrared spectra from isotopic and symmetry transformations

    SciTech Connect

    Rey, Michaël Tyuterev, Vladimir G.; Nikitin, Andrei V.

    2014-07-28

    Accurate variational high-resolution spectra calculations in the range 0-8000 cm{sup −1} are reported for the first time for the monodeutered methane ({sup 12}CH{sub 3}D). Global calculations were performed by using recent ab initio surfaces for line positions and line intensities derived from the main isotopologue {sup 12}CH{sub 4}. Calculation of excited vibrational levels and high-J rovibrational states is described by using the normal mode Eckart-Watson Hamiltonian combined with irreducible tensor formalism and appropriate numerical procedures for solving the quantum nuclear motion problem. The isotopic H→D substitution is studied in details by means of symmetry and nonlinear normal mode coordinate transformations. Theoretical spectra predictions are given up to J = 25 and compared with the HITRAN 2012 database representing a compilation of line lists derived from analyses of experimental spectra. The results are in very good agreement with available empirical data suggesting that a large number of yet unassigned lines in observed spectra could be identified and modeled using the present approach.

  1. Three-Dimensional Reflectance Traction Microscopy

    PubMed Central

    Jones, Christopher A. R.; Groves, Nicholas Scott; Sun, Bo

    2016-01-01

    Cells in three-dimensional (3D) environments exhibit very different biochemical and biophysical phenotypes compared to the behavior of cells in two-dimensional (2D) environments. As an important biomechanical measurement, 2D traction force microscopy can not be directly extended into 3D cases. In order to quantitatively characterize the contraction field, we have developed 3D reflectance traction microscopy which combines confocal reflection imaging and partial volume correlation postprocessing. We have measured the deformation field of collagen gel under controlled mechanical stress. We have also characterized the deformation field generated by invasive breast cancer cells of different morphologies in 3D collagen matrix. In contrast to employ dispersed tracing particles or fluorescently-tagged matrix proteins, our methods provide a label-free, computationally effective strategy to study the cell mechanics in native 3D extracellular matrix. PMID:27304456

  2. Three-dimensional reconstruction of light microscopy image sections: present and future.

    PubMed

    Wang, Yuzhen; Xu, Rui; Luo, Gaoxing; Wu, Jun

    2015-03-01

    Three-dimensional (3D) image reconstruction technologies can reveal previously hidden microstructures in human tissue. However, the lack of ideal, non-destructive cross-sectional imaging techniques is still a problem. Despite some drawbacks, histological sectioning remains one of the most powerful methods for accurate high-resolution representation of tissue structures. Computer technologies can produce 3D representations of interesting human tissue and organs that have been serial-sectioned, dyed or stained, imaged, and segmented for 3D visualization. 3D reconstruction also has great potential in the fields of tissue engineering and 3D printing. This article outlines the most common methods for 3D tissue section reconstruction. We describe the most important academic concepts in this field, and provide critical explanations and comparisons. We also note key steps in the reconstruction procedures, and highlight recent progress in the development of new reconstruction methods.

  3. A three-dimensional dynamic vorticity vector associated with tropical oceanic convection

    NASA Astrophysics Data System (ADS)

    Gao, Shouting

    2007-09-01

    The relationship between cloud hydrometeors and the dynamic vorticity vector (DVV) is investigated using hourly data from a three-dimensional (3D), 5-day cloud-resolving model (CRM) simulation during the Tropical Rainfall Measuring Mission (TRMM) Kwajalein Experiment (KWAJEX). Horizontal components of the 3D DVV (which represent the interaction between vertical vorticity and horizontal winds) show higher linear correlation coefficients with cloud hydrometeors than does the vertical component. This is different from the two-dimensional (2D) results from Gao et al. (2005), which show that both zonal and vertical components of 2D DVV have good linear correlations with convection. The difference is caused by the fact that dominant items in horizontal components of the 3D DVV are excluded from that of the 2D DVV. This suggests that three-dimensional representation of tropical deep convection is crucial to accurately simulate convection and associated dynamics.

  4. Development of Three-Dimensional Completion of Complex Objects

    ERIC Educational Resources Information Center

    Soska, Kasey C.; Johnson, Scott P.

    2013-01-01

    Three-dimensional (3D) object completion, the ability to perceive the backs of objects seen from a single viewpoint, emerges at around 6 months of age. Yet, only relatively simple 3D objects have been used in assessing its development. This study examined infants' 3D object completion when presented with more complex stimuli. Infants…

  5. Reconstruction of high resolution MLC leaf positions using a low resolution detector for accurate 3D dose reconstruction in IMRT

    NASA Astrophysics Data System (ADS)

    Visser, R.; Godart, J.; Wauben, D. J. L.; Langendijk, J. A.; van't Veld, A. A.; Korevaar, E. W.

    2016-12-01

    In pre-treatment dose verification, low resolution detector systems are unable to identify shifts of individual leafs of high resolution multi leaf collimator (MLC) systems from detected changes in the dose deposition. The goal of this study was to introduce an alternative approach (the shutter technique) combined with a previous described iterative reconstruction method to accurately reconstruct high resolution MLC leaf positions based on low resolution measurements. For the shutter technique, two additional radiotherapy treatment plans (RT-plans) were generated in addition to the original RT-plan; one with even MLC leafs closed for reconstructing uneven leaf positions and one with uneven MLC leafs closed for reconstructing even leaf positions. Reconstructed leaf positions were then implemented in the original RT-plan for 3D dose reconstruction. The shutter technique was evaluated for a 6 MV Elekta SLi linac with 5 mm MLC leafs (Agility™) in combination with the MatriXX Evolution detector with detector spacing of 7.62 mm. Dose reconstruction was performed with the COMPASS system (v2.0). The measurement setup allowed one row of ionization chambers to be affected by two adjacent leaf pairs. Measurements were obtained for various field sizes with MLC leaf position errors ranging from 1.0 mm to 10.0 mm. Furthermore, one clinical head and neck IMRT treatment beam with MLC introduced leaf position errors of 5.0 mm was evaluated to illustrate the impact of the shutter technique on 3D dose reconstruction. Without the shutter technique, MLC leaf position reconstruction showed reconstruction errors up to 6.0 mm. Introduction of the shutter technique allowed MLC leaf position reconstruction for the majority of leafs with sub-millimeter accuracy resulting in a reduction of dose reconstruction errors. The shutter technique in combination with the iterative reconstruction method allows high resolution MLC leaf position reconstruction using low resolution

  6. Computer-Generated, Three-Dimensional Character Animation.

    ERIC Educational Resources Information Center

    Van Baerle, Susan Lynn

    This master's thesis begins by discussing the differences between 3-D computer animation of solid three-dimensional, or monolithic, objects, and the animation of characters, i.e., collections of movable parts with soft pliable surfaces. Principles from two-dimensional character animation that can be transferred to three-dimensional character…

  7. EFFICIENT THREE-DIMENSIONAL NLTE DUST RADIATIVE TRANSFER WITH SKIRT

    SciTech Connect

    Baes, Maarten; Verstappen, Joris; De Looze, Ilse; Fritz, Jacopo; Saftly, Waad; Vidal Perez, Edgardo; Stalevski, Marko; Valcke, Sander

    2011-10-01

    We present an updated version of SKIRT, a three-dimensional (3D) Monte Carlo radiative transfer code developed to simulate dusty galaxies. The main novel characteristics of the SKIRT code are the use of a stellar foam to generate random positions, an efficient combination of eternal forced scattering and continuous absorption, and a new library approach that links the radiative transfer code to the DustEM dust emission library. This approach enables a fast, accurate, and self-consistent calculation of the dust emission of arbitrary mixtures of transiently heated dust grains and polycyclic aromatic hydrocarbons, even for full 3D models containing millions of dust cells. We have demonstrated the accuracy of the SKIRT code through a set of simulations based on the edge-on spiral galaxy UGC 4754. The models we ran were gradually refined from a smooth, two-dimensional, local thermal equilibrium (LTE) model to a fully 3D model that includes non-LTE (NLTE) dust emission and a clumpy structure of the dusty interstellar medium. We find that clumpy models absorb UV and optical radiation less efficiently than smooth models with the same amount of dust, and that the dust in clumpy models is on average both cooler and less luminous. Our simulations demonstrate that, given the appropriate use of optimization techniques, it is possible to efficiently and accurately run Monte Carlo radiative transfer simulations of arbitrary 3D structures of several million dust cells, including a full calculation of the NLTE emission by arbitrary dust mixtures.

  8. Assessing 3d Photogrammetry Techniques in Craniometrics

    NASA Astrophysics Data System (ADS)

    Moshobane, M. C.; de Bruyn, P. J. N.; Bester, M. N.

    2016-06-01

    Morphometrics (the measurement of morphological features) has been revolutionized by the creation of new techniques to study how organismal shape co-varies with several factors such as ecophenotypy. Ecophenotypy refers to the divergence of phenotypes due to developmental changes induced by local environmental conditions, producing distinct ecophenotypes. None of the techniques hitherto utilized could explicitly address organismal shape in a complete biological form, i.e. three-dimensionally. This study investigates the use of the commercial software, Photomodeler Scanner® (PMSc®) three-dimensional (3D) modelling software to produce accurate and high-resolution 3D models. Henceforth, the modelling of Subantarctic fur seal (Arctocephalus tropicalis) and Antarctic fur seal (Arctocephalus gazella) skulls which could allow for 3D measurements. Using this method, sixteen accurate 3D skull models were produced and five metrics were determined. The 3D linear measurements were compared to measurements taken manually with a digital caliper. In addition, repetitive measurements were recorded by varying researchers to determine repeatability. To allow for comparison straight line measurements were taken with the software, assuming that close accord with all manually measured features would illustrate the model's accurate replication of reality. Measurements were not significantly different demonstrating that realistic 3D skull models can be successfully produced to provide a consistent basis for craniometrics, with the additional benefit of allowing non-linear measurements if required.

  9. Use of 3D Printed Models in Medical Education: A Randomized Control Trial Comparing 3D Prints versus Cadaveric Materials for Learning External Cardiac Anatomy

    ERIC Educational Resources Information Center

    Lim, Kah Heng Alexander; Loo, Zhou Yaw; Goldie, Stephen J.; Adams, Justin W.; McMenamin, Paul G.

    2016-01-01

    Three-dimensional (3D) printing is an emerging technology capable of readily producing accurate anatomical models, however, evidence for the use of 3D prints in medical education remains limited. A study was performed to assess their effectiveness against cadaveric materials for learning external cardiac anatomy. A double blind randomized…

  10. Three-dimensional Simulation of Backward Raman Amplification

    SciTech Connect

    A.A. Balakin; G.M. Fraiman; N.J. Fisch

    2005-11-12

    Three-dimensional (3-D) simulations for the Backward Raman Amplification (BRA) are presented. The images illustrate the effects of pump depletion, pulse diffraction, non-homogeneous plasma density, and plasma ionization.

  11. A 3D assessment tool for accurate volume measurement for monitoring the evolution of cutaneous leishmaniasis wounds.

    PubMed

    Zvietcovich, Fernando; Castañeda, Benjamin; Valencia, Braulio; Llanos-Cuentas, Alejandro

    2012-01-01

    Clinical assessment and outcome metrics are serious weaknesses identified on the systematic reviews of cutaneous Leishmaniasis wounds. Methods with high accuracy and low-variability are required to standarize study outcomes in clinical trials. This work presents a precise, complete and noncontact 3D assessment tool for monitoring the evolution of cutaneous Leishmaniasis (CL) wounds based on a 3D laser scanner and computer vision algorithms. A 3D mesh of the wound is obtained by a commercial 3D laser scanner. Then, a semi-automatic segmentation using active contours is performed to separate the ulcer from the healthy skin. Finally, metrics of volume, area, perimeter and depth are obtained from the mesh. Traditional manual 3D and 3D measurements are obtained as a gold standard. Experiments applied to phantoms and real CL wounds suggest that the proposed 3D assessment tool provides higher accuracy (error <2%) and precision rates (error <4%) than conventional manual methods (precision error < 35%). This 3D assessment tool provides high accuracy metrics which deserve more formal prospective study.

  12. Detailed and Highly Accurate 3d Models of High Mountain Areas by the Macs-Himalaya Aerial Camera Platform

    NASA Astrophysics Data System (ADS)

    Brauchle, J.; Hein, D.; Berger, R.

    2015-04-01

    Remote sensing in areas with extreme altitude differences is particularly challenging. In high mountain areas specifically, steep slopes result in reduced ground pixel resolution and degraded quality in the DEM. Exceptionally high brightness differences can in part no longer be imaged by the sensors. Nevertheless, detailed information about mountainous regions is highly relevant: time and again glacier lake outburst floods (GLOFs) and debris avalanches claim dozens of victims. Glaciers are sensitive to climate change and must be carefully monitored. Very detailed and accurate 3D maps provide a basic tool for the analysis of natural hazards and the monitoring of glacier surfaces in high mountain areas. There is a gap here, because the desired accuracies are often not achieved. It is for this reason that the DLR Institute of Optical Sensor Systems has developed a new aerial camera, the MACS-Himalaya. The measuring unit comprises four camera modules with an overall aperture angle of 116° perpendicular to the direction of flight. A High Dynamic Range (HDR) mode was introduced so that within a scene, bright areas such as sun-flooded snow and dark areas such as shaded stone can be imaged. In 2014, a measuring survey was performed on the Nepalese side of the Himalayas. The remote sensing system was carried by a Stemme S10 motor glider. Amongst other targets, the Seti Valley, Kali-Gandaki Valley and the Mt. Everest/Khumbu Region were imaged at heights up to 9,200 m. Products such as dense point clouds, DSMs and true orthomosaics with a ground pixel resolution of up to 15 cm were produced. Special challenges and gaps in the investigation of high mountain areas, approaches for resolution of these problems, the camera system and the state of evaluation are presented with examples.

  13. Three dimensional magnetic abacus memory

    PubMed Central

    Zhang, ShiLei; Zhang, JingYan; Baker, Alexander A.; Wang, ShouGuo; Yu, GuangHua; Hesjedal, Thorsten

    2014-01-01

    Stacking nonvolatile memory cells into a three-dimensional matrix represents a powerful solution for the future of magnetic memory. However, it is technologically challenging to access the data in the storage medium if large numbers of bits are stacked on top of each other. Here we introduce a new type of multilevel, nonvolatile magnetic memory concept, the magnetic abacus. Instead of storing information in individual magnetic layers, thereby having to read out each magnetic layer separately, the magnetic abacus adopts a new encoding scheme. It is inspired by the idea of second quantisation, dealing with the memory state of the entire stack simultaneously. Direct read operations are implemented by measuring the artificially engineered ‘quantised' Hall voltage, each representing a count of the spin-up and spin-down layers in the stack. This new memory system further allows for both flexible scaling of the system and fast communication among cells. The magnetic abacus provides a promising approach for future nonvolatile 3D magnetic random access memory. PMID:25146338

  14. Three-dimensional relativistic electromagnetic subcycle solitons.

    PubMed

    Esirkepov, Timur; Nishihara, Katsunobu; Bulanov, Sergei V; Pegoraro, Francesco

    2002-12-30

    Three-dimensional (3D) relativistic electromagnetic subcycle solitons were observed in 3D particle-in-cell simulations of an intense short-laser-pulse propagation in an underdense plasma. Their structure resembles that of an oscillating electric dipole with a poloidal electric field and a toroidal magnetic field that oscillate in phase with the electron density with frequency below the Langmuir frequency. On the ion time scale, the soliton undergoes a Coulomb explosion of its core, resulting in ion acceleration, and then evolves into a slowly expanding quasineutral cavity.

  15. Fat-Suppressed Gadolinium-Enhanced Three-Dimensional Magnetic Resonance Angiography Adequately Depicts the Status of Iliac Arteries Following Atherectomy and Stent Placement

    SciTech Connect

    Amano, Yasuo; Gemma, Kazuhito; Kawamata, Hiroshi; Kumazaki, Tatsuo

    1998-07-15

    Fat-suppressed, three-dimensional magnetic resonance angiography (3D MRA) was performed on nine patients with 11 iliac artery stenoses following atherectomy or stent placement. The MRA accurately depicted continued patency, restenosis, or aneurysm formation when compared with immediate posttreatment conventional arteriography. Therefore MRA is accurate and can be used independently for clinical decision making.

  16. Three-dimensional terahertz wave imaging.

    PubMed

    Zhang, X-C

    2004-02-15

    Pulsed terahertz (THz) wave sensing and imaging is a coherent measurement technology. Like radar, based on the phase and amplitude of the THz pulse at each frequency, THz waves provide temporal and spectroscopic information that allows us to develop various three-dimensional (3D) terahertz tomographic imaging modalities. The 3D THz tomographic imaging methods we investigated include THz time-of-flight tomography, THz computed tomography (CT) and THz binary lens tomography. THz time-of-flight uses the THz pulses as a probe beam to temporally mark the target, and then constructs a 3D image of the target using the THz waves scattered by the target. THz CT is based on geometrical optics and inspired from X-ray CT. THz binary lens tomography uses the frequency-dependent focal-length property of binary lenses to obtain tomographic images of an object. Three-dimensional THz imaging has potential in such applications as non-destructive inspection. The interaction between a coherent THz pulse and an object provides rich information about the object under study; therefore, 3D THz imaging can be used to inspect or characterize dielectric and semiconductor objects. For example, 3D THz imaging has been used to detect and identify the defects inside a Space Shuttle insulation tile.

  17. Three dimensional Dirac semimetals

    NASA Astrophysics Data System (ADS)

    Zaheer, Saad

    We extend the physics of graphene to three dimensional systems by showing that Dirac points can exist on the Fermi surface of realistic materials in three dimensions. Many of the exotic electronic properties of graphene can be ascribed to the pseudorelativistic behavior of its charge carriers due to two dimensional Dirac points on the Fermi surface. We show that certain nonsymmorphic spacegroups exhibit Dirac points among the irreducible representations of the appropriate little group at high symmetry points on the surface of the Brillouin zone. We provide a list of all Brillouin zone momenta in the 230 spacegroups that can host Dirac points. We describe microscopic considerations necessary to design materials in one of the candidate spacegroups such that the Dirac point appears at the Fermi energy without any additional non-Dirac-like Fermi pockets. We use density functional theory based methods to propose six new Dirac semimetals: BiO 2 and SbO2 in the beta-cristobalite lattice (spacegroup 227), and BiCaSiO4, BiMgSiO4, BiAlInO 4, and BiZnSiO4 in the distorted spinels lattice (spacegroup 74). Additionally we derive effective Dirac Hamiltonians given group representative operators as well as tight binding models incorporating spin-orbit coupling. Finally we study the Fermi surface of zincblende (spacegroup 216) HgTe which is effectively point-like at Gamma in the Brillouin zone and exhibits accidental degeneracies along a threefold rotation axis. Whereas compressive strain gaps the band structure into a topological insulator, tensile strain shifts the accidental degeneracies away from Gamma and enlarges the Fermi surface. States on the Fermi surface exhibit nontrivial spin texture marked by winding of spins around the threefold rotation axis and by spin vortices indicating a change in the winding number. This is confirmed by microscopic calculations performed in tensile strained HgTe and Hg0.5Zn 0.5 Te as well as k.p theory. We conclude with a summary of recent

  18. A system of three-dimensional complex variables

    NASA Technical Reports Server (NTRS)

    Martin, E. Dale

    1986-01-01

    Some results of a new theory of multidimensional complex variables are reported, including analytic functions of a three-dimensional (3-D) complex variable. Three-dimensional complex numbers are defined, including vector properties and rules of multiplication. The necessary conditions for a function of a 3-D variable to be analytic are given and shown to be analogous to the 2-D Cauchy-Riemann equations. A simple example also demonstrates the analogy between the newly defined 3-D complex velocity and 3-D complex potential and the corresponding ordinary complex velocity and complex potential in two dimensions.

  19. ’MBTI3D’ (A Three-Dimensional Interpretation)

    DTIC Science & Technology

    1993-04-01

    INFP , etc.). Over the years the METI has become a cornerstone of the HRD industry--over two- million people completed it in the United States alone...ISTJ 1-21, S-23, T-49, and J- 1. L. ENTJ E 43, N 23, T- 9, and J- 5. 15 ErT l - -P,,i I T !ITP ESFP INFP LITP F E7TFD EY-rP E :FP E•śP B E ESTJ E,5

  20. A method to evaluate the three-dimensional roughness of fracture surfaces in brittle geomaterials.

    PubMed

    Tatone, Bryan S A; Grasselli, Giovanni

    2009-12-01

    Conventionally, the evaluation of fracture surface roughness in brittle geomaterials, such as concrete and rock, has been based on the measurement and analysis of two-dimensional profiles rather than three-dimensional (3D) surfaces. The primary reason for doing so was the lack of tools capable of making 3D measurements. However, in recent years, several optical and mechanical measurement tools have become available, which are capable of quickly and accurately producing high resolution point clouds defining 3D surfaces. This paper provides a methodology for evaluating the surface roughness and roughness anisotropy using these 3D surface measurements. The methodology is presented step-by-step to allow others to easily adopt and implement the process to analyze their own surface measurement data. The methodology is demonstrated by digitizing a series of concrete fracture surfaces and comparing the estimated 3D roughness parameters with qualitative observations and estimates of the well-known roughness coefficient, R(s).

  1. Depth-tunable three-dimensional display with interactive light field control

    NASA Astrophysics Data System (ADS)

    Xie, Songlin; Wang, Peng; Sang, Xinzhu; Li, Chenyu; Dou, Wenhua; Xiao, Liquan

    2016-07-01

    A software-defined depth-tunable three-dimensional (3D) display with interactive 3D depth control is presented. With the proposed post-processing system, the disparity of the multi-view media can be freely adjusted. Benefiting from a wealth of information inherently contains in dense multi-view images captured with parallel arrangement camera array, the 3D light field is built and the light field structure is controlled to adjust the disparity without additional acquired depth information since the light field structure itself contains depth information. A statistical analysis based on the least square is carried out to extract the depth information inherently exists in the light field structure and the accurate depth information can be used to re-parameterize light fields for the autostereoscopic display, and a smooth motion parallax can be guaranteed. Experimental results show that the system is convenient and effective to adjust the 3D scene performance in the 3D display.

  2. Prediction of geometrically feasible three-dimensional structures of pseudoknotted RNA through free energy estimation

    PubMed Central

    Zhang, Jian; Dundas, Joseph; Lin, Ming; Chen, Rong; Wang, Wei; Liang, Jie

    2009-01-01

    Accurate free energy estimation is essential for RNA structure prediction. The widely used Turner's energy model works well for nested structures. For pseudoknotted RNAs, however, there is no effective rule for estimation of loop entropy and free energy. In this work we present a new free energy estimation method, termed the pseudoknot predictor in three-dimensional space (pk3D), which goes beyond Turner's model. Our approach treats nested and pseudoknotted structures alike in one unifying physical framework, regardless of how complex the RNA structures are. We first test the ability of pk3D in selecting native structures from a large number of decoys for a set of 43 pseudoknotted RNA molecules, with lengths ranging from 23 to 113. We find that pk3D performs slightly better than the Dirks and Pierce extension of Turner's rule. We then test pk3D for blind secondary structure prediction, and find that pk3D gives the best sensitivity and comparable positive predictive value (related to specificity) in predicting pseudoknotted RNA secondary structures, when compared with other methods. A unique strength of pk3D is that it also generates spatial arrangement of structural elements of the RNA molecule. Comparison of three-dimensional structures predicted by pk3D with the native structure measured by nuclear magnetic resonance or X-ray experiments shows that the predicted spatial arrangement of stems and loops is often similar to that found in the native structure. These close-to-native structures can be used as starting points for further refinement to derive accurate three-dimensional structures of RNA molecules, including those with pseudoknots. PMID:19864433

  3. Developing a 3D constrained variational analysis method to obtain accurate gridded atmospheric vertical velocity and horizontal advections

    NASA Astrophysics Data System (ADS)

    Tang, S.; Zhang, M.

    2013-12-01

    Based on the constrained variational analysis (CVA) algorithm developed by Zhang and Lin (1997), a 3-dimensional (3D) version of CVA is developed. The new algorithm used gridded surface and TOA observations as constraints to adjust atmospheric state variables in each grid point to satisfy column-integrated mass, moisture and static energy conservation. From the process of adjustment a set of high-quality 3D large-scale forcing data (vertical velocity and horizontal advections) can be derived to drive Single-Column models (SCM), Cloud-Resolving Models (CRM) and Large-Eddy Simulations (LES) to evaluate and improve parameterizations. Since the 3D CVA can adjust gridded state variables from any data source with observed precipitation, radiation and surface fluxes, it also gives a potential possibility to use this algorithm in data assimilation system to assimilate precipitation and radiation data.

  4. Accurate visualization and quantification of coronary vasculature by 3D/4D fusion from biplane angiography and intravascular ultrasound

    NASA Astrophysics Data System (ADS)

    Wahle, Andreas; Mitchell, Steven C.; Olszewski, Mark E.; Long, Ryan M.; Sonka, Milan

    2001-01-01

    In the rapidly evolving field of intravascular ultrasound (IVUS) for tissue characterization and visualization, the assessment of vessel morphology still lacks a geometrically correct 3D reconstruction. The IVUS frames are usually stacked up to form a straight vessel, neglecting curvature and the axial twisting of the catheter during the pullback. This paper presents a comprehensive system for geometrically correct reconstruction of IVUS images by fusion with biplane angiography, thus combining the advantages of both modalities. Vessel cross-section and tissue characteristics are obtained form IVUS, while the 3D locations are derived by geometrical reconstruction from the angiographic projections. ECG-based timing ensures a proper match of the image data with the respective heart phase. The fusion is performed for each heart phase individually, thus yielding the 4-D data as a set of 3-D reconstructions.

  5. Three-dimensional representation of complex muscle architectures and geometries.

    PubMed

    Blemker, Silvia S; Delp, Scott L

    2005-05-01

    Almost all computer models of the musculoskeletal system represent muscle geometry using a series of line segments. This simplification (i) limits the ability of models to accurately represent the paths of muscles with complex geometry and (ii) assumes that moment arms are equivalent for all fibers within a muscle (or muscle compartment). The goal of this work was to develop and evaluate a new method for creating three-dimensional (3D) finite-element models that represent complex muscle geometry and the variation in moment arms across fibers within a muscle. We created 3D models of the psoas, iliacus, gluteus maximus, and gluteus medius muscles from magnetic resonance (MR) images. Peak fiber moment arms varied substantially among fibers within each muscle (e.g., for the psoas the peak fiber hip flexion moment arms varied from 2 to 3 cm, and for the gluteus maximus the peak fiber hip extension moment arms varied from 1 to 7 cm). Moment arms from the literature were generally within the range of fiber moment arms predicted by the 3D models. The models accurately predicted changes in muscle surface geometry over a 55 degrees range of hip flexion, as compared to changes in shape predicted from MR images (average errors between the model and measured surfaces were between 1.7 and 5.2 mm). This new framework for representing muscle will enhance the accuracy of computer models of the musculoskeletal system.

  6. Three-dimensional echocardiographic technology.

    PubMed

    Salgo, Ivan S

    2007-05-01

    This article addresses the current state of the art of technology in three-dimensional echocardiography as it applies to transducer design, beam forming, display, and quantification. Because three-dimensional echocardiography encompasses many technical and clinical areas, this article reviews its strengths and limitations and concludes with an analysis of what to use when.

  7. Accurate registration of random radiographic projections based on three spherical references for the purpose of few-view 3D reconstruction

    SciTech Connect

    Schulze, Ralf; Heil, Ulrich; Weinheimer, Oliver; Gross, Daniel; Bruellmann, Dan; Thomas, Eric; Schwanecke, Ulrich; Schoemer, Elmar

    2008-02-15

    Precise registration of radiographic projection images acquired in almost arbitrary geometries for the purpose of three-dimensional (3D) reconstruction is beset with difficulties. We modify and enhance a registration method [R. Schulze, D. D. Bruellmann, F. Roeder, and B. d'Hoedt, Med. Phys. 31, 2849-2854 (2004)] based on coupling a minimum amount of three reference spheres in arbitrary positions to a rigid object under study for precise a posteriori pose estimation. Two consecutive optimization procedures (a, initial guess; b, iterative coordinate refinement) are applied to completely exploit the reference's shadow information for precise registration of the projections. The modification has been extensive, i.e., only the idea of using the sphere shadows to locate each sphere in three dimensions from each projection was retained whereas the approach to extract the shadow information has been changed completely and extended. The registration information is used for subsequent algebraic reconstruction of the 3D information inherent in the projections. We present a detailed mathematical theory of the registration process as well as simulated data investigating its performance in the presence of error. Simulation of the initial guess revealed a mean relative error in the critical depth coordinate ranging between 2.1% and 4.4%, and an evident error reduction by the subsequent iterative coordinate refinement. To prove the applicability of the method for real-world data, algebraic 3D reconstructions from few ({<=}9) projection radiographs of a human skull, a human mandible and a teeth-containing mandible segment are presented. The method facilitates extraction of 3D information from only few projections obtained from off-the-shelf radiographic projection units without the need for costly hardware. Technical requirements as well as radiation dose are low.

  8. Three-dimensional electroanatomic entrainment map in atypical atrial flutter late after heart transplantation.

    PubMed

    Roten, Laurent; Tanner, Hildegard; Goy, Jean-Jacques; Delacrétaz, Etienne

    2010-02-01

    Atrial flutter in the donor part of orthotopic heart transplants has been reported and successfully treated by radiofrequency ablation of the cavotricuspid isthmus, but mapping and ablation of atypical flutter circuits may be challenging.(1) Entrainment mapping has been used in combination with activation mapping to define the mechanism of atypical atrial flutter. Here, we report a case where colour-coded three-dimensional (3D) entrainment mapping allowed us to accurately determine and visualize the 3D location of the reentrant circuit and to plan the ablation of a left atrial flutter without the need for activation mapping.

  9. Fabrication of three-dimensional terahertz photonic crystals with diamond structure by particle manipulation assembly

    NASA Astrophysics Data System (ADS)

    Takagi, Kenta; Kawasaki, Akira

    2009-01-01

    We reported the fabrication of terahertz photonic crystals by three-dimensional (3D) particle manipulation assembly. Our method, which is based on pick-and-place manipulation and interparticle laser welding, enabled accurate assembling of an arbitrary 3D structure, regardless of particle polydispersity. By using this method, we fabricated a diamond crystal from ZrO2/polyethylene composite particles (diameter of 400 μm). The obtained crystal exhibited a photonic stop gap in the ⟨111⟩ direction; this result was in good agreement with the theoretical result, suggesting that the crystal has a full photonic bandgap at around 0.2 THz.

  10. Automatic three-dimensional underground mine mapping

    SciTech Connect

    Huber, D.F.; Vandapel, N.

    2006-01-15

    For several years, our research group has been developing methods for automated modeling of three-dimensional environments. In September 2002, we were given the opportunity to demonstrate our mapping capability in an underground coal mine. The opportunity arose as a result of the Quecreek mine accident, in which an inaccurate map caused miners to breach an abandoned, water-filled mine, trapping them for several days. Our field test illustrates the feasibility and potential of high-resolution 3D mapping of an underground coal mine using a cart-mounted 3D laser scanner In this paper we present our experimental setup, the automatic 3D modeling method used, and the results of the field test.

  11. Scaffolding for Three-Dimensional Embryonic Vasculogenesis

    NASA Astrophysics Data System (ADS)

    Kraehenbuehl, Thomas P.; Aday, Sezin; Ferreira, Lino S.

    Biomaterial scaffolds have great potential to support efficient vascular differentiation of embryonic stem cells. Vascular cell fate-specific biochemical and biophysical cues have been identified and incorporated into three-dimensional (3D) biomaterials to efficiently direct embryonic vasculogenesis. The resulting vascular-like tissue can be used for regenerative medicine applications, further elucidation of biophysical and biochemical cues governing vasculogenesis, and drug discovery. In this chapter, we give an overview on the following: (1) developmental cues for directed differentiation of human embryonic stem cells (hESCs) into vascular cells, (2) 3D vascular differentiation in embryoid bodies (EBs), (3) preparation of 3D scaffolds for the vascular differentiation of hESCs, and (4) the most significant studies combining scaffolding and hESCs for development of vascular-like tissue.

  12. Three dimensional carbon-nanotube polymers.

    PubMed

    Zhao, Zhisheng; Xu, Bo; Wang, Li-Min; Zhou, Xiang-Feng; He, Julong; Liu, Zhongyuan; Wang, Hui-Tian; Tian, Yongjun

    2011-09-27

    Eight fascinating sp(2)- and sp(3)-hybridized carbon allotropes have been uncovered using a newly developed ab initio particle-swarm optimization methodology for crystal structure prediction. These crystalline allotropes can be viewed respectively as three-dimensional (3D) polymers of (4,0), (5,0), (7,0), (8,0), (9,0), (3,3), (4,4), and (6,6) carbon nanotubes, termed 3D-(n, 0) or 3D-(n, n) carbons. The ground-state energy calculations show that the carbons all have lower energies than C(60) fullerene, and some are energetically more stable than the van der Waals packing configurations of their nanotube parents. Owing to their unique configurations, they have distinctive electronic properties, high Young's moduli, high tensile strength, ultrahigh hardness, good ductility, and low density, and may be potentially applied to a variety of needs.

  13. One-, Two-, and Three-Dimensional Heterospin Complexes Consisting of 4-(N-tert-Butyloxylamino)pyridine (4NOpy), Dicyanamide Ion (DCA), and 3d Metal Ions: Crystal Structures and Magnetic Properties of [M(II)(4NOpy)x(DCA)y(CH3CN)z]n (M = Mn, Co, Ni, Cu, Zn).

    PubMed

    Ogawa, Hiraku; Mori, Koya; Murashima, Kensuke; Karasawa, Satoru; Koga, Noboru

    2016-01-19

    Solutions of 3d metal ion salts, M(NO3)2, 4-(N-tert-butyloxylamino)pyridine (4NOpy), and dicyanamide (DCA) in CH3CN were mixed to afford single crystals of the polymeric complexes [M(II)(4NOpy)x(DCA)y(CH3CN)z]n (M(II) = Mn (1), Co (2), Ni (3), Cu (4a and 4b), Zn (5)). X-ray crystallography revealed that the crystal structures are a three-dimensional (3-D) network for 1, 2-D networks for 2, 3, 4a, and 5, and a 1-D chain for 4b. Crystals of 2, 3, 4a, and 5 contained CH3CN molecules as crystal solvents, which were readily desorbed in the ambient atmosphere. After desorption of the CH3CN molecules, the crystal structures of 2 and 3 were confirmed to be slightly shrunk without destruction of the crystal lattice. Crystals of 2, 3, 4a, and 5 after desorption of crystal solvents were used for investigations of the magnetic properties. Complex 1 showed antiferromagnetic interactions to form a ferrimagnetic chain and exhibited the magnetic behavior of a 2-D (or 3-D) spin-canted antiferromagnet with TN = 12 K. Complex 2 containing anisotropic Co(II) ions also showed the behavior of a 1-D (or 2-D) spin-canted antiferromagnet with TN = 6 K. In 3, 4a, and 4b, the aminoxyl of 4NOpy ferromagnetically interacted with the metal ion with coupling constants of JM-NO/kB = 45, 45, and 43 K, respectively. In 5, the magnetic couplings between the aminoxyls in 4NOpy through the diamagnetic Zn(II) ion were weakly antiferromagntic (JNO-NO = -1.2 K). DCA might be a weak antiferromagnetic connector for the metal chains.

  14. 3-D Time-Accurate CFD Simulations of a Multi-Megawatt Slender Bladed HAWT under Yawed Inflow Conditions

    NASA Astrophysics Data System (ADS)

    Sayed, M.; Lutz, Th.; Krämer, E.

    2016-09-01

    In the present study numerical investigations of a generic Multi-Megawatt slender bladed Horizontal-Axis Wind Turbine (HAWT) under yawed inflow conditions were conducted. A three-dimensional URANS flow solver based on structured overlapping meshes was used. The simulations were conducted at wind speeds of 7m/sec, 11 m/sec and 15 m/sec for different yaw angles ranging from +60° to -60°. It was concluded that, for below rated wind speeds, under small yaw angles (below ±15°) the magnitudes of the blade forces are slightly increased, while under high yaw angles (above ±15°) there is a significant decrease. Moreover, the load fluctuations, for the different yaw angles, have the same frequency but different amplitude and oscillation shape. It was concluded that at the above rated wind speed of 15 m/sec, the blade aerodynamic loads are significantly affected by the yaw inflow conditions and the magnitude values of the loads are decreased with increasing yaw angle. It can be concluded that the angle of attack and the tower interference are the utmost variables affecting the yawed turbines.

  15. Digital Three-dimensional Reconstruction Based On Integral Imaging

    PubMed Central

    Li, Chao; Chen, Qian; Hua, Hong; Mao, Chen; Shao, Ajun

    2015-01-01

    This paper presents a digital three dimensional reconstruction method based on a set of small-baseline elemental images captured with a micro-lens array and a CCD sensor. In this paper, we adopt the ASIFT (Affine Scale-invariant feature transform) operator as the image registration method. Among the set of captured elemental images, the elemental image located in the middle of the overall image field is used as the reference and corresponding matching points in each elemental image around the reference elemental are calculated, which enables to accurately compute the depth value of object points relatively to the reference image frame. Using optimization algorithm with redundant matching points can achieve 3D reconstruction finally. Our experimental results are presented to demonstrate excellent performance in accuracy and speed of the proposed algorithm. PMID:26236151

  16. Three-Dimensional Optical Coherence Tomography

    NASA Technical Reports Server (NTRS)

    Gutin, Mikhail; Wang, Xu-Ming; Gutin, Olga

    2009-01-01

    Three-dimensional (3D) optical coherence tomography (OCT) is an advanced method of noninvasive infrared imaging of tissues in depth. Heretofore, commercial OCT systems for 3D imaging have been designed principally for external ophthalmological examination. As explained below, such systems have been based on a one-dimensional OCT principle, and in the operation of such a system, 3D imaging is accomplished partly by means of a combination of electronic scanning along the optical (Z) axis and mechanical scanning along the two axes (X and Y) orthogonal to the optical axis. In 3D OCT, 3D imaging involves a form of electronic scanning (without mechanical scanning) along all three axes. Consequently, the need for mechanical adjustment is minimal and the mechanism used to position the OCT probe can be correspondingly more compact. A 3D OCT system also includes a probe of improved design and utilizes advanced signal- processing techniques. Improvements in performance over prior OCT systems include finer resolution, greater speed, and greater depth of field.

  17. Three dimensional imaging with randomly distributed sensors.

    PubMed

    DaneshPanah, Mehdi; Javidi, Bahram; Watson, Edward A

    2008-04-28

    As a promising three dimensional passive imaging modality, Integral Imaging (II) has been investigated widely within the research community. In virtually all of such investigations, there is an implicit assumption that the collection of elemental images lie on a simple geometric surface (e.g. flat, concave, etc), also known as pickup surface. In this paper, we present a generalized framework for 3D II with arbitrary pickup surface geometry and randomly distributed sensor configuration. In particular, we will study the case of Synthetic Aperture Integral Imaging (SAII) with random location of cameras in space, while all cameras have parallel optical axes but different distances from the 3D scene. We assume that the sensors are randomly distributed in 3D volume of pick up space. For 3D reconstruction, a finite number of sensors with known coordinates are randomly selected from within this volume. The mathematical framework for 3D scene reconstruction is developed based on an affine transform representation of imaging under geometrical optics regime. We demonstrate the feasibility of the methods proposed here by experimental results. To the best of our knowledge, this is the first report on 3D imaging using randomly distributed sensors.

  18. Generation of three-dimensional medical thermograms.

    PubMed

    Chan, F H; So, A T; Lam, F K

    1996-01-01

    To visualise non-invasively human organs in their true form and shape has intrigued mankind for centuries. Three-dimensional (3D) imaging is one recent development that has brought us closer to fulfilling the age-old quest of non-invasive visualisation so that diagnoses by doctors can be efficiently enhanced. Nowadays, 3D CT and MRI images have been very popular. Thermography is an important medical imaging technique that displays the temperature distribution on the surface of a human organ and it has been proved to be significant in offering a unique physiological reflection of pathology that may confirm or enhance the anatomic findings of other diagnostic imaging modalities. It is the only imaging modality that can evaluate pain whereas plain radiographs, CT and MRI, etc. can only depict structural anatomic abnormalities that may not always coincide with patients' clinical complaints. It is against this background that 3D thermograms have been developed. A set of comprehensive calibration procedures for the 3-camera system have been designed based on different models for the optical and infrared cameras. The accuracy of the results is high enough to produce 3D thermograms that can be used to correlate with the 3D images from other medical imaging modalities. One important achievement of the system is that the resultant 3D images are absolutely dimensioned and hence, it is particularly favourable for fully autonomous applications with robots. The system can also provide an overall picture of both the structural abnormalities and nervous responses of patients.

  19. In-lab three-dimensional printing

    PubMed Central

    Partridge, Roland; Conlisk, Noel; Davies, Jamie A.

    2012-01-01

    The development of the microscope in 1590 by Zacharias Janssenby and Hans Lippershey gave the world a new way of visualizing details of morphogenesis and development. More recent improvements in this technology including confocal microscopy, scanning electron microscopy (SEM) and optical projection tomography (OPT) have enhanced the quality of the resultant image. These technologies also allow a representation to be made of a developing tissue’s three-dimensional (3-D) form. With all these techniques however, the image is delivered on a flat two-dimensional (2-D) screen. 3-D printing represents an exciting potential to reproduce the image not simply on a flat screen, but in a physical, palpable three-dimensional structure. Here we explore the scope that this holds for exploring and interacting with the structure of a developing organ in an entirely novel way. As well as being useful for visualization, 3-D printers are capable of rapidly and cost-effectively producing custom-made structures for use within the laboratory. We here describe the advantages of producing hardware for a tissue culture system using an inexpensive in-lab printer. PMID:22652907

  20. Three dimensional dynamics of rotating structures under mixed boundary conditions

    NASA Astrophysics Data System (ADS)

    Bediz, Bekir; Romero, L. A.; Ozdoganlar, O. Burak

    2015-12-01

    This paper presents the spectral-Tchebychev (ST) technique for solution of three dimensional (3D) dynamics of rotating structures. In particular, structures that exhibit coupled dynamic response require a 3D modeling approach to capture their dynamic behavior. Rotational motions further complicate this behavior, inducing coriolis, centrifugal softening, and (nonlinear) stress-stiffening effects. Therefore, a 3D solution approach is needed to accurately capture the rotational dynamics. The presented 3D-ST technique provides a fast-converging and precise solution approach for rotational dynamics of structures with complex geometries and mixed boundary conditions. Specifically, unlike finite elements techniques, the presented technique uses a series expansion approach considering distributed-parameter system equations: The integral boundary value problem for rotating structures is discretized using the spectral-Tchebychev approach. To simplify the domain of the structures, cross-sectional and rotational transformations are applied to problems with curved cross-section and pretwisted geometry. The nonlinear terms included in the integral boundary value problem are linearized around an equilibrium solution using the quasi-static method. As a result, mass, damping, and stiffness matrices, as well as a forcing vector, are obtained for a given rotating structure. Several case studies are then performed to demonstrate the application and effectiveness of the 3D-ST solution. For each problem, the natural frequencies and modes shapes from the 3D-ST solution are compared to those from the literature (when available) and to those from a commercial finite elements software. The case studies include rotating/spinning parallelepipeds under free and mixed boundary conditions, and a cantilevered pretwisted beam (i.e., rotating blade) with an airfoil geometry rotating on a hub. It is seen that the natural frequencies and mode shapes from the 3D-ST technique differ from those from the

  1. Numerical investigations in three-dimensional internal flows

    NASA Technical Reports Server (NTRS)

    Rose, William C.

    1991-01-01

    The present study is a preliminary investigation into the behavior of the flow within a 28 degree total geometric turning angle hypothetical Mach 10 inlet as calculated with the full three-dimensional Navier-Stokes equations. Comparison between the two-dimensional and three-dimensional solutions have been made. The overall compression is not significantly different between the two-dimensional and center plane three dimensional solutions. Approximately one-half to two-thirds of the inlet flow at the exit of the inlet behave nominally two-dimensionally. On the other hand, flow field non-uniformities in the three-dimensional solution indicate the potential significance of the sidewall boundary layer flows ingested into the inlet. The tailoring of the geometry at the inlet shoulder and on the cowl obtained in the two-dimensional parametric design study have also proved to be effective at controlling the boundary layer behavior in the three-dimensional code. The three-dimensional inlet solution remained started indicating that the two-dimensional design had a sufficient margin to allow for three-dimensional flow field effects. Although confidence is being gained in the use of SCRAM3D (three-dimensional full Navier-Stokes code) as applied to similar flow fields, the actual effects of the three-dimensional flow fields associated with sidewalls and wind tunnel installations can require verification with ground-based experiments.

  2. Realistic 3D computer model of the gerbil middle ear, featuring accurate morphology of bone and soft tissue structures.

    PubMed

    Buytaert, Jan A N; Salih, Wasil H M; Dierick, Manual; Jacobs, Patric; Dirckx, Joris J J

    2011-12-01

    In order to improve realism in middle ear (ME) finite-element modeling (FEM), comprehensive and precise morphological data are needed. To date, micro-scale X-ray computed tomography (μCT) recordings have been used as geometric input data for FEM models of the ME ossicles. Previously, attempts were made to obtain these data on ME soft tissue structures as well. However, due to low X-ray absorption of soft tissue, quality of these images is limited. Another popular approach is using histological sections as data for 3D models, delivering high in-plane resolution for the sections, but the technique is destructive in nature and registration of the sections is difficult. We combine data from high-resolution μCT recordings with data from high-resolution orthogonal-plane fluorescence optical-sectioning microscopy (OPFOS), both obtained on the same gerbil specimen. State-of-the-art μCT delivers high-resolution data on the 3D shape of ossicles and other ME bony structures, while the OPFOS setup generates data of unprecedented quality both on bone and soft tissue ME structures. Each of these techniques is tomographic and non-destructive and delivers sets of automatically aligned virtual sections. The datasets coming from different techniques need to be registered with respect to each other. By combining both datasets, we obtain a complete high-resolution morphological model of all functional components in the gerbil ME. The resulting 3D model can be readily imported in FEM software and is made freely available to the research community. In this paper, we discuss the methods used, present the resulting merged model, and discuss the morphological properties of the soft tissue structures, such as muscles and ligaments.

  3. Three-dimensional measurement of small mechanical parts under a complicated background based on stereo vision

    SciTech Connect

    Ren Zhiguo; Liao Jiarui; Cai Lilong

    2010-04-01

    We present an effective method for the accurate three-dimensional (3D) measurement of small industrial parts under a complicated noisy background, based on stereo vision. To effectively extract the nonlinear features of desired curves of the measured parts in the images, a strategy from coarse to fine extraction is employed, based on a virtual motion control system. By using the multiscale decomposition of gray images and virtual beam chains, the nonlinear features can be accurately extracted. By analyzing the generation of geometric errors, the refined feature points of the desired curves are extracted. Then the 3D structure of the measured parts can be accurately reconstructed and measured with least squares errors. Experimental results show that the presented method can accurately measure industrial parts that are represented by various line segments and curves.

  4. Three-dimensional measurement of small mechanical parts under a complicated background based on stereo vision.

    PubMed

    Ren, Zhiguo; Liao, Jiarui; Cai, Lilong

    2010-04-01

    We present an effective method for the accurate three-dimensional (3D) measurement of small industrial parts under a complicated noisy background, based on stereo vision. To effectively extract the nonlinear features of desired curves of the measured parts in the images, a strategy from coarse to fine extraction is employed, based on a virtual motion control system. By using the multiscale decomposition of gray images and virtual beam chains, the nonlinear features can be accurately extracted. By analyzing the generation of geometric errors, the refined feature points of the desired curves are extracted. Then the 3D structure of the measured parts can be accurately reconstructed and measured with least squares errors. Experimental results show that the presented method can accurately measure industrial parts that are represented by various line segments and curves.

  5. Three-Dimensional Frame Buffers For Interactive Analysis Of Three-Dimensional Data

    NASA Astrophysics Data System (ADS)

    Hunter, Gregory M.

    1986-02-01

    Two-dimensional data such as photos, x-rays, various types of satellite images, sonar, radar, seismic plots, etc., in many cases must be analyzed using frame buffers for purposes of medical diagnoses, crop estimates, mineral exploration, and so forth. In many cases the same types of sensors used to gather such samples in two dimensions can gather 3D data for even more effective analysis. Just as 2D arrays of data can be analyzed using frame buffers, three-dimensional data can be analyzed using SOLIDS-BUFFER memories. Image processors deal with samples from two-dimensional arrays and are based on frame buffers. The SOLIDS PROCESSOR system deals with samples from a three-dimensional volume, or solid, and is based on a 3D frame buffer. This paper focuses upon the SOLIDS-BUFFER system as used in the INSIGHT SOLIDS-PROCESSOR system from Phoenix Data Systems.

  6. Human gesture recognition using three-dimensional integral imaging.

    PubMed

    Javier Traver, V; Latorre-Carmona, Pedro; Salvador-Balaguer, Eva; Pla, Filiberto; Javidi, Bahram

    2014-10-01

    Three-dimensional (3D) integral imaging allows one to reconstruct a 3D scene, including range information, and provides sectional refocused imaging of 3D objects at different ranges. This paper explores the potential use of 3D passive sensing integral imaging for human gesture recognition tasks from sequences of reconstructed 3D video scenes. As a preliminary testbed, the 3D integral imaging sensing is implemented using an array of cameras with the appropriate algorithms for 3D scene reconstruction. Recognition experiments are performed by acquiring 3D video scenes of multiple hand gestures performed by ten people. We analyze the capability and performance of gesture recognition using 3D integral imaging representations at given distances and compare its performance with the use of standard two-dimensional (2D) single-camera videos. To the best of our knowledge, this is the first report on using 3D integral imaging for human gesture recognition.

  7. Three-dimensional Dendritic Needle Network model with application to Al-Cu directional solidification experiments

    SciTech Connect

    Tourret, D.; Karma, A.; Clarke, A. J.; Gibbs, P. J.; Imhoff, S. D.

    2015-06-11

    We present a three-dimensional (3D) extension of a previously proposed multi-scale Dendritic Needle Network (DNN) approach for the growth of complex dendritic microstructures. Using a new formulation of the DNN dynamics equations for dendritic paraboloid-branches of a given thickness, one can directly extend the DNN approach to 3D modeling. We validate this new formulation against known scaling laws and analytical solutions that describe the early transient and steady-state growth regimes, respectively. Finally, we compare the predictions of the model to in situ X-ray imaging of Al-Cu alloy solidification experiments. The comparison shows a very good quantitative agreement between 3D simulations and thin sample experiments. It also highlights the importance of full 3D modeling to accurately predict the primary dendrite arm spacing that is significantly over-estimated by 2D simulations.

  8. Three-dimensional structure measurement of diamond crowns based on stereo vision.

    PubMed

    Ren, Zhiguo; Cai, Lilong

    2009-11-01

    We present an effective method for reconstructing and measuring the three-dimensional (3D) structures of diamond crowns based on stereo vision. To reach high measurement accuracy, the influences of 3D measurement errors are analyzed in detail. Then, a method to accurately extract the linear features of diamond edges based on virtual motion control is described. Depending on the obtained linear features, the 3D structure of a diamond crown can be reconstructed with least squares error. The validity of the proposed method is verified by experiments. The results show that the proposed method can be used to measure the 3D structures of diamond crowns with satisfactory accuracy and efficiency, and it also can be used to extract linear features and measure other similar artificial objects that can be represented by line segments.

  9. Three-dimensional Dendritic Needle Network model with application to Al-Cu directional solidification experiments

    DOE PAGES

    Tourret, D.; Karma, A.; Clarke, A. J.; ...

    2015-06-11

    We present a three-dimensional (3D) extension of a previously proposed multi-scale Dendritic Needle Network (DNN) approach for the growth of complex dendritic microstructures. Using a new formulation of the DNN dynamics equations for dendritic paraboloid-branches of a given thickness, one can directly extend the DNN approach to 3D modeling. We validate this new formulation against known scaling laws and analytical solutions that describe the early transient and steady-state growth regimes, respectively. Finally, we compare the predictions of the model to in situ X-ray imaging of Al-Cu alloy solidification experiments. The comparison shows a very good quantitative agreement between 3D simulationsmore » and thin sample experiments. It also highlights the importance of full 3D modeling to accurately predict the primary dendrite arm spacing that is significantly over-estimated by 2D simulations.« less

  10. Microwave imaging for breast cancer detection: advances in three--dimensional image reconstruction.

    PubMed

    Golnabi, Amir H; Meaney, Paul M; Epstein, Neil R; Paulsen, Keith D

    2011-01-01

    Microwave imaging is based on the electrical property (permittivity and conductivity) differences in materials. Microwave imaging for biomedical applications is particularly interesting, mainly due to the fact that available range of dielectric properties for different tissues can provide important functional information about their health. Under the assumption that a 3D scattering problem can be reasonably represented as a simplified 2D model, one can take advantage of the simplicity and lower computational cost of 2D models to characterize such 3D phenomenon. Nonetheless, by eliminating excessive model simplifications, 3D microwave imaging provides potentially more valuable information over 2D techniques, and as a result, more accurate dielectric property maps may be obtained. In this paper, we present some advances we have made in three-dimensional image reconstruction, and show the results from a 3D breast phantom experiment using our clinical microwave imaging system at Dartmouth Hitchcock Medical Center (DHMC), NH.

  11. Accurate quantification of local changes for carotid arteries in 3D ultrasound images using convex optimization-based deformable registration

    NASA Astrophysics Data System (ADS)

    Cheng, Jieyu; Qiu, Wu; Yuan, Jing; Fenster, Aaron; Chiu, Bernard

    2016-03-01

    Registration of longitudinally acquired 3D ultrasound (US) images plays an important role in monitoring and quantifying progression/regression of carotid atherosclerosis. We introduce an image-based non-rigid registration algorithm to align the baseline 3D carotid US with longitudinal images acquired over several follow-up time points. This algorithm minimizes the sum of absolute intensity differences (SAD) under a variational optical-flow perspective within a multi-scale optimization framework to capture local and global deformations. Outer wall and lumen were segmented manually on each image, and the performance of the registration algorithm was quantified by Dice similarity coefficient (DSC) and mean absolute distance (MAD) of the outer wall and lumen surfaces after registration. In this study, images for 5 subjects were registered initially by rigid registration, followed by the proposed algorithm. Mean DSC generated by the proposed algorithm was 79:3+/-3:8% for lumen and 85:9+/-4:0% for outer wall, compared to 73:9+/-3:4% and 84:7+/-3:2% generated by rigid registration. Mean MAD of 0:46+/-0:08mm and 0:52+/-0:13mm were generated for lumen and outer wall respectively by the proposed algorithm, compared to 0:55+/-0:08mm and 0:54+/-0:11mm generated by rigid registration. The mean registration time of our method per image pair was 143+/-23s.

  12. Three-dimensional imaging technique using optical diffraction

    NASA Astrophysics Data System (ADS)

    Tan, Sheng; Hart, Douglas P.

    2002-02-01

    This paper presents a novel fast and simple technique to measure three-dimensional (3D) objects. An integrated 3D camera is built, which features a motorized off-axis rotating aperture. A regular spot pattern projection adds texture onto smooth 3D objects. When rotating, the off-axis aperture translates depth information into blurred image diameter. The displacement of each spot between two arbitrary aperture positions reveals depth. A pseudo- correlation algorithm based on optical diffraction is proposed to measure spot displacement fast and accurately. When subtracting two consecutive images of a roughly Gaussian-shaped displaced spot, the normalized subtraction intensity peak height is directly proportional to the spot displacement. The peak height to displacement calibration curve is specifically defined by optical parameters of the imaging system. Proper combination of off-axis aperture location and magnification ratio determines the size of the measurement range. Experiment observations show that the calibration curve is highly smooth and sensitive to the spot displacement at sub-pixel level. Real-time processing is possible with only order of image size arithmetic operations. The proposed technique holds potential for various industrial machine vision applications.

  13. A three-dimensional measurement method for medical electric endoscope

    NASA Astrophysics Data System (ADS)

    Zhou, Tingting; Tao, Pei; Yuan, Bo; Wang, Liqiang

    2017-01-01

    One method for three-dimensional (3D) measurement based on structured light is proposed for the medical electric endoscope in the present study. The structured light of black and white strips is generated by that the point sources illuminate the grating mask plate. Four point sources are aligned linearly by a certain space and they are lighted sequentially. Then four images of modulated fringes by the height of object with different phase shifts can be obtained. The algorithm proposed by Wang Z is employed to extract the accurate phase shift from the fringe images since the phase shift cannot be exactly set as π/2 by hardware. An experimental prototype endoscope was built according to the proposed method. One high-definition CMOS camera module developed by ourselves was used to acquire the endoscopic images and the structured light was generated by four fiber LEDs and a transmission grating with a pitch of 0.1 mm. one C# program was designed to light up LEDs in turn, acquire the phase shifted images and calculate the 3D information. The experimental results indicate that its precise of depth measurement at the working distance of 40 mm is better than 0.5 mm and its consuming time of 3D depth calculation is less than 0.5 s.

  14. Layer-oriented computer-generated holograms for three-dimensional display

    NASA Astrophysics Data System (ADS)

    Cao, Liangcai; Zhao, Yan; Zhang, Hao; Zong, Song; Kong, Dezhao; Jin, Guofan

    2016-09-01

    Depth cues and full-parallax are crucial issues in the calculation of computer-generated holograms (CGHs) for perfect holographic three-dimensional (3-D) display. In order to accelerate the speed of generating CGHs and improve the display quality, three layer-oriented methods are investigated in this paper. The first method is based on angularspectrum, which can provide accurate depth cues. The second method is based on inverse Fresnel diffraction layered holographic stereogram to provide accurate depth information as well as correct occlusion effect. The third method is proposed to generate zoomable 3-D CGHs using layer-based shifted Fresnel diffraction. Numerical simulations and optical experiments have demonstrated that the proposed methods can reconstruct quality 3-D images.

  15. [Three Dimensional Display in Nuclear Medicine].

    PubMed

    Teraoka, Satomi; Souma, Tsutomu

    2015-01-01

    Imaging techniques to obtain a tomographic image in nuclear medicine such as PET and SPECT are widely used. It is necessary to interpreting all of the tomographic images obtained in order to accurately evaluate the individual lesion, whereas three dimensional display is often useful in order to overview and evaluate the feature of the entire lesion or disease such as the position, size and abnormal pattern. In Japan, the use of three dimensional image analysis workstation with an application of the co-registration and image fusion between the functional images such as PET or SPECT and anatomical images such as CT or MRI has been generalized. In addition, multimodality imaging system such as a PET/CT and SPECT/CT has been widespread. Therefore, it is expected to improve the diagnostic accuracy using three dimensionally image fusion to functional images with poor anatomical information. In this commentary, as an example of a three dimensional display that are commonly used in nuclear medicine examination in Japan, brain regions, cardiac region and bone and tumor region will be introduced separately.

  16. Interactive dynamic three-dimensional scene for the ground-based three-dimensional display

    NASA Astrophysics Data System (ADS)

    Hou, Peining; Sang, Xinzhu; Guo, Nan; Chen, Duo; Yan, Binbin; Wang, Kuiru; Dou, Wenhua; Xiao, Liquan

    2016-10-01

    Three-dimensional (3D) displays provides valuable tools for many fields, such as scientific experiment, education, information transmission, medical imaging and physical simulation. Ground based 360° 3D display with dynamic and controllable scene can find some special applications, such as design and construction of buildings, aeronautics, military sand table and so on. It can be utilized to evaluate and visualize the dynamic scene of the battlefield, surgical operation and the 3D canvas of art. In order to achieve the ground based 3D display, the public focus plane should be parallel to the camera's imaging planes, and optical axes should be offset to the center of public focus plane in both vertical and horizontal directions. Virtual cameras are used to display 3D dynamic scene with Unity 3D engine. Parameters of virtual cameras for capturing scene are designed and analyzed, and locations of virtual cameras are determined by the observer's eye positions in the observing space world. An interactive dynamic 3D scene for ground based 360° 3D display is demonstrated, which provides high-immersion 3D visualization.

  17. 3D gaze tracking system for NVidia 3D Vision®.

    PubMed

    Wibirama, Sunu; Hamamoto, Kazuhiko

    2013-01-01

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

  18. Three-dimensional MR imaging in the assessment of physeal growth arrest.

    PubMed

    Sailhan, Frédéric; Chotel, Franck; Guibal, Anne-Laure; Gollogly, Sohrab; Adam, Philippe; Bérard, Jérome; Guibaud, Laurent

    2004-09-01

    The purpose of this study is to describe an imaging method for identifying and characterising physeal growth arrest following physeal plate aggression. The authors describe the use of three-dimensional MRI performed with fat-suppressed three-dimensional spoiled gradient-recalled echo sequences followed by manual image reconstruction to create a 3D model of the physeal plate. This retrospective series reports the analysis of 33 bony physeal bridges in 28 children (mean age 10.5 years) with the use of fat-suppressed three-dimensional spoiled gradient-recalled echo imaging and 3D reconstructions from the source images. 3D reconstructions were obtained after the outlining was done manually on each source image. Files of all patients were reviewed for clinical data at the time of MRI, type of injury, age at MRI and bone bridge characteristics on reconstructions. Twenty-one (63%) of the 33 bridges were post-traumatic and were mostly situated in the lower extremities (19/21). The distal tibia was involved in 66% (14/21) of the cases. Bridges due to causes other than trauma were located in the lower extremities in 10/12 cases, and the distal femur represented 60% of these cases. Of the 28 patients, five presented with two bridges involving two different growth plates making a total of 33 physeal bone bars. The location and shape of each bridge was accurately identified in each patient, and in post-traumatic cases, 89% of bone bars were of Ogden type III (central) or I (peripheral). Reconstructions were obtained in 15 min and are easy to interpret. Volumes of the physeal bone bridge(s) and of the remaining normal physis were calculated. The bone bridging represented less than 1% to 47% of the total physeal plate volume. The precise shape and location of the bridge can be visualised on the 3D reconstructions. This information is useful in the surgical management of these deformities; as for the eight patients who underwent bone bar resection, an excellent correspondence was

  19. Accurate and high-performance 3D position measurement of fiducial marks by stereoscopic system for railway track inspection

    NASA Astrophysics Data System (ADS)

    Gorbachev, Alexey A.; Serikova, Mariya G.; Pantyushina, Ekaterina N.; Volkova, Daria A.

    2016-04-01

    Modern demands for railway track measurements require high accuracy (about 2-5 mm) of rails placement along the track to ensure smooth, safe and fast transportation. As a mean for railways geometry measurements we suggest a stereoscopic system which measures 3D position of fiducial marks arranged along the track by image processing algorithms. The system accuracy was verified during laboratory tests by comparison with precise laser tracker indications. The accuracy of +/-1.5 mm within a measurement volume 150×400×5000 mm was achieved during the tests. This confirmed that the stereoscopic system demonstrates good measurement accuracy and can be potentially used as fully automated mean for railway track inspection.

  20. Three-Dimensional Imaging. Chapter 10

    NASA Technical Reports Server (NTRS)

    Kelso, R. M.; Delo, C.

    1999-01-01

    This chapter is concerned with three-dimensional imaging of fluid flows. Although relatively young, this field of research has already yielded an enormous range of techniques. These vary widely in cost and complexity, with the cheapest light sheet systems being within the budgets of most laboratories, and the most expensive Magnetic Resonance Imaging systems available to a select few. Taking the view that the most likely systems to be developed are those using light sheets, the authors will relate their knowledge and experience of such systems. Other systems will be described briefly and references provided. Flows are inherently three-dimensional in structure; even those generated around nominally 2-D surface geometry. It is becoming increasingly apparent to scientists and engineers that the three-dimensionalities, both large and small scale, are important in terms of overall flow structure and species, momentum, and energy transport. Furthermore, we are accustomed to seeing the world in three dimensions, so it is natural that we should wish to view, measure and interpret flows in three-dimensions. Unfortunately, 3-D images do not lend themselves to convenient presentation on the printed page, and this task is one of the challenges facing us.

  1. Accuracy of three-dimensional printing for manufacturing replica teeth

    PubMed Central

    Lee, Keun-Young; Cho, Jin-Woo; Chang, Na-Young; Chae, Jong-Moon; Kang, Kyung-Hwa; Kim, Sang-Cheol

    2015-01-01

    Objective Three-dimensional (3D) printing is a recent technological development that may play a significant role in orthodontic diagnosis and treatment. It can be used to fabricate skull models or study models, as well as to make replica teeth in autotransplantation or tooth impaction cases. The aim of this study was to evaluate the accuracy of fabrication of replica teeth made by two types of 3D printing technologies. Methods Fifty extracted molar teeth were selected as samples. They were scanned to generate high-resolution 3D surface model stereolithography files. These files were converted into physical models using two types of 3D printing technologies: Fused deposition modeling (FDM) and PolyJet technology. All replica teeth were scanned and 3D images generated. Computer software compared the replica teeth to the original teeth with linear measurements, volumetric measurements, and mean deviation measurements with best-fit alignment. Paired t-tests were used to statistically analyze the measurements. Results Most measurements of teeth formed using FDM tended to be slightly smaller, while those of the PolyJet replicas tended to be slightly larger, than those of the extracted teeth. Mean deviation measurements with best-fit alignment of FDM and PolyJet group were 0.047 mm and 0.038 mm, respectively. Although there were statistically significant differences, they were regarded as clinically insignificant. Conclusions This study confirms that FDM and PolyJet technologies are accurate enough to be usable in orthodontic diagnosis and treatment. PMID:26445716

  2. Three-dimensional planning in craniomaxillofacial surgery

    PubMed Central

    Rubio-Palau, Josep; Prieto-Gundin, Alejandra; Cazalla, Asteria Albert; Serrano, Miguel Bejarano; Fructuoso, Gemma Garcia; Ferrandis, Francisco Parri; Baró, Alejandro Rivera

    2016-01-01

    Introduction: Three-dimensional (3D) planning in oral and maxillofacial surgery has become a standard in the planification of a variety of conditions such as dental implants and orthognathic surgery. By using custom-made cutting and positioning guides, the virtual surgery is exported to the operating room, increasing precision and improving results. Materials and Methods: We present our experience in the treatment of craniofacial deformities with 3D planning. Software to plan the different procedures has been selected for each case, depending on the procedure (Nobel Clinician, Kodak 3DS, Simplant O&O, Dolphin 3D, Timeus, Mimics and 3-Matic). The treatment protocol is exposed step by step from virtual planning, design, and printing of the cutting and positioning guides to patients’ outcomes. Conclusions: 3D planning reduces the surgical time and allows predicting possible difficulties and complications. On the other hand, it increases preoperative planning time and needs a learning curve. The only drawback is the cost of the procedure. At present, the additional preoperative work can be justified because of surgical time reduction and more predictable results. In the future, the cost and time investment will be reduced. 3D planning is here to stay. It is already a fact in craniofacial surgery and the investment is completely justified by the risk reduction and precise results. PMID:28299272

  3. Detection of congenital uterine malformation by using transvaginal three-dimensional ultrasound.

    PubMed

    Yu, Li-Li; Zhang, Xuan; Zhang, Ting; Chen, Han-Rong; Wang, Ze-Hua

    2014-10-01

    This study assessed the clinical application of transvaginal three-dimensional ultrasound (3D TVUS) in the diagnosis of congenital uterine malformation. A retrospective study was performed on 62 patients with congenital uterine malformation confirmed hysteroscopically and/or laparoscopically. The patients were subjected to transvaginal two-dimensional ultrasound (2D TVUS) and 3D TVUS. The accuracy rate was compared between the two methods. The accuracy rate of 3D TVUS was (98.38%, 61/62), higher than that of 2D TVUS (80.65%, 50/62). 3D TVUS coronal plane imaging could demonstrate the internal shape of the endometrial cavity and the external contour of the uterine fundus. It allowed accurate measurement on the coronary plane, and could three-dimensionally show the image of cervical tube, thereby providing information for the diagnosis of some complex uterine malformation. 3D TVUS imaging can obtain comprehensive information of the uterus malformation, and it is superior to 2D TVUS for the diagnosis of congenital uterine malformations, especially complex uterine anomaly.

  4. A 3D-CFD code for accurate prediction of fluid flows and fluid forces in seals

    NASA Technical Reports Server (NTRS)

    Athavale, M. M.; Przekwas, A. J.; Hendricks, R. C.

    1994-01-01

    Current and future turbomachinery requires advanced seal configurations to control leakage, inhibit mixing of incompatible fluids and to control the rotodynamic response. In recognition of a deficiency in the existing predictive methodology for seals, a seven year effort was established in 1990 by NASA's Office of Aeronautics Exploration and Technology, under the Earth-to-Orbit Propulsion program, to develop validated Computational Fluid Dynamics (CFD) concepts, codes and analyses for seals. The effort will provide NASA and the U.S. Aerospace Industry with advanced CFD scientific codes and industrial codes for analyzing and designing turbomachinery seals. An advanced 3D CFD cylindrical seal code has been developed, incorporating state-of-the-art computational methodology for flow analysis in straight, tapered and stepped seals. Relevant computational features of the code include: stationary/rotating coordinates, cylindrical and general Body Fitted Coordinates (BFC) systems, high order differencing schemes, colocated variable arrangement, advanced turbulence models, incompressible/compressible flows, and moving grids. This paper presents the current status of code development, code demonstration for predicting rotordynamic coefficients, numerical parametric study of entrance loss coefficients for generic annular seals, and plans for code extensions to labyrinth, damping, and other seal configurations.

  5. Atypical late-time singular regimes accurately diagnosed in stagnation-point-type solutions of 3D Euler flows

    NASA Astrophysics Data System (ADS)

    Mulungye, Rachel M.; Lucas, Dan; Bustamante, Miguel D.

    2016-02-01

    We revisit, both numerically and analytically, the finite-time blowup of the infinite-energy solution of 3D Euler equations of stagnation-point-type introduced by Gibbon et al. (1999). By employing the method of mapping to regular systems, presented in Bustamante (2011) and extended to the symmetry-plane case by Mulungye et al. (2015), we establish a curious property of this solution that was not observed in early studies: before but near singularity time, the blowup goes from a fast transient to a slower regime that is well resolved spectrally, even at mid-resolutions of $512^2.$ This late-time regime has an atypical spectrum: it is Gaussian rather than exponential in the wavenumbers. The analyticity-strip width decays to zero in a finite time, albeit so slowly that it remains well above the collocation-point scale for all simulation times $t < T^* - 10^{-9000}$, where $T^*$ is the singularity time. Reaching such a proximity to singularity time is not possible in the original temporal variable, because floating point double precision ($\\approx 10^{-16}$) creates a `machine-epsilon' barrier. Due to this limitation on the \\emph{original} independent variable, the mapped variables now provide an improved assessment of the relevant blowup quantities, crucially with acceptable accuracy at an unprecedented closeness to the singularity time: $T^*- t \\approx 10^{-140}.$

  6. Performing accurate joint kinematics from 3-D in vivo image sequences through consensus-driven simultaneous registration.

    PubMed

    Jacq, Jean-José; Cresson, Thierry; Burdin, Valérie; Roux, Christian

    2008-05-01

    This paper addresses the problem of the robust registration of multiple observations of the same object. Such a problem typically arises whenever it becomes necessary to recover the trajectory of an evolving object observed through standard 3-D medical imaging techniques. The instances of the tracked object are assumed to be variously truncated, locally subject to morphological evolutions throughout the sequence, and imprinted with significant segmentation errors as well as significant noise perturbations. The algorithm operates through the robust and simultaneous registration of all surface instances of a given object through median consensus. This operation consists of two interwoven processes set up to work in close collaboration. The first one progressively generates a median and implicit shape computed with respect to current estimations of the registration transformations, while the other refines these transformations with respect to the current estimation of their median shape. When compared with standard robust techniques, tests reveal significant improvements, both in robustness and precision. The algorithm is based on widely-used techniques, and proves highly effective while offering great flexibility of utilization.

  7. Three-dimensional television: a broadcaster's perspective

    NASA Astrophysics Data System (ADS)

    Jolly, S. J. E.; Armstrong, M.; Salmon, R. A.

    2009-02-01

    The recent resurgence of interest in the stereoscopic cinema and the increasing availability to the consumer of stereoscopic televisions and computer displays are leading broadcasters to consider, once again, the feasibility of stereoscopic broadcasting. High Definition Television is now widely deployed, and the R&D departments of broadcasters and consumer electronics manufacturers are starting to plan future enhancements to the experience of television. Improving the perception of depth via stereoscopy is a strong candidate technology. In this paper we will consider the challenges associated with the production, transmission and display of different forms of "three-dimensional" television. We will explore options available to a broadcaster wishing to start a 3D service using the technologies available at the present time, and consider how they could be improved to enable many more television programmes to be recorded and transmitted in a 3D-compatible form, paying particular attention to scenarios such as live broadcasting, where the workflows developed for the stereoscopic cinema are inapplicable. We will also consider the opportunities available for broadcasters to reach audiences with "three-dimensional" content via other media in the near future: for example, distributing content via the existing stereoscopic cinema network, or over the Internet to owners of stereoscopic computer displays.

  8. Three-dimensional marginal separation

    NASA Technical Reports Server (NTRS)

    Duck, Peter W.

    1988-01-01

    The three dimensional marginal separation of a boundary layer along a line of symmetry is considered. The key equation governing the displacement function is derived, and found to be a nonlinear integral equation in two space variables. This is solved iteratively using a pseudo-spectral approach, based partly in double Fourier space, and partly in physical space. Qualitatively, the results are similar to previously reported two dimensional results (which are also computed to test the accuracy of the numerical scheme); however quantitatively the three dimensional results are much different.

  9. Piezoelectric characteristics of three-dimensional solid object of poly(l-lactide) fabricated by three-dimensional printing

    NASA Astrophysics Data System (ADS)

    Hayashi, Syota; Kamimura, Yuki; Tsukamoto, Nobuyuki; Imoto, Kenji; Sugitani, Hideki; Kondo, Takashi; Imada, Yuya; Nakiri, Takuo; Tajitsu, Yoshiro

    2015-10-01

    Through three-dimensional (3D) printing, we attempted to fabricate 3D solid objects with piezoelectricity. By optimizing the conditions of 3D printing, we realized the fabrication of a piezoelectric object by 3D printing. In fact, we could produce a poly(l-lactide) (PLLA) object similar to a smart phone case fabricated by 3D printing, the molded body of which has button sensors at the desired sites by exploiting the piezoelectric properties of PLLA. Finally, we confirmed that the PLLA object behaved as a fully functional sensor.

  10. Three-dimensional segmentation of luminal and adventitial borders in serial intravascular ultrasound images

    NASA Technical Reports Server (NTRS)

    Shekhar, R.; Cothren, R. M.; Vince, D. G.; Chandra, S.; Thomas, J. D.; Cornhill, J. F.

    1999-01-01

    Intravascular ultrasound (IVUS) provides exact anatomy of arteries, allowing accurate quantitative analysis. Automated segmentation of IVUS images is a prerequisite for routine quantitative analyses. We present a new three-dimensional (3D) segmentation technique, called active surface segmentation, which detects luminal and adventitial borders in IVUS pullback examinations of coronary arteries. The technique was validated against expert tracings by computing correlation coefficients (range 0.83-0.97) and William's index values (range 0.37-0.66). The technique was statistically accurate, robust to image artifacts, and capable of segmenting a large number of images rapidly. Active surface segmentation enabled geometrically accurate 3D reconstruction and visualization of coronary arteries and volumetric measurements.

  11. Construction of Three Dimensional Solutions for the Maxwell Equations

    NASA Technical Reports Server (NTRS)

    Yefet, A.; Turkel, E.

    1998-01-01

    We consider numerical solutions for the three dimensional time dependent Maxwell equations. We construct a fourth order accurate compact implicit scheme and compare it to the Yee scheme for free space in a box.

  12. Three-dimensional imaging modalities in endodontics

    PubMed Central

    Mao, Teresa

    2014-01-01

    Recent research in endodontics has highlighted the need for three-dimensional imaging in the clinical arena as well as in research. Three-dimensional imaging using computed tomography (CT) has been used in endodontics over the past decade. Three types of CT scans have been studied in endodontics, namely cone-beam CT, spiral CT, and peripheral quantitative CT. Contemporary endodontics places an emphasis on the use of cone-beam CT for an accurate diagnosis of parameters that cannot be visualized on a two-dimensional image. This review discusses the role of CT in endodontics, pertaining to its importance in the diagnosis of root canal anatomy, detection of peri-radicular lesions, diagnosis of trauma and resorption, presurgical assessment, and evaluation of the treatment outcome. PMID:25279337

  13. Three-dimensional imaging modalities in endodontics.

    PubMed

    Mao, Teresa; Neelakantan, Prasanna

    2014-09-01

    Recent research in endodontics has highlighted the need for three-dimensional imaging in the clinical arena as well as in research. Three-dimensional imaging using computed tomography (CT) has been used in endodontics over the past decade. Three types of CT scans have been studied in endodontics, namely cone-beam CT, spiral CT, and peripheral quantitative CT. Contemporary endodontics places an emphasis on the use of cone-beam CT for an accurate diagnosis of parameters that cannot be visualized on a two-dimensional image. This review discusses the role of CT in endodontics, pertaining to its importance in the diagnosis of root canal anatomy, detection of peri-radicular lesions, diagnosis of trauma and resorption, presurgical assessment, and evaluation of the treatment outcome.

  14. [Accurate 3D free-form registration between fan-beam CT and cone-beam CT].

    PubMed

    Liang, Yueqiang; Xu, Hongbing; Li, Baosheng; Li, Hongsheng; Yang, Fujun

    2012-06-01

    Because the X-ray scatters, the CT numbers in cone-beam CT cannot exactly correspond to the electron densities. This, therefore, results in registration error when the intensity-based registration algorithm is used to register planning fan-beam CT and cone-beam CT. In order to reduce the registration error, we have developed an accurate gradient-based registration algorithm. The gradient-based deformable registration problem is described as a minimization of energy functional. Through the calculus of variations and Gauss-Seidel finite difference method, we derived the iterative formula of the deformable registration. The algorithm was implemented by GPU through OpenCL framework, with which the registration time was greatly reduced. Our experimental results showed that the proposed gradient-based registration algorithm could register more accurately the clinical cone-beam CT and fan-beam CT images compared with the intensity-based algorithm. The GPU-accelerated algorithm meets the real-time requirement in the online adaptive radiotherapy.

  15. Three-dimensional CT angiography: a new technique for imaging microvascular anatomy.

    PubMed

    Tregaskiss, Ashley P; Goodwin, Adam N; Bright, Linda D; Ziegler, Craig H; Acland, Robert D

    2007-03-01

    To date there has been no satisfactory research method for imaging microvascular anatomy in three dimensions (3D). In this article we present a new technique that allows both qualitative and quantitative examination of the microvasculature in 3D. In 10 fresh cadavers (7 females, 3 males, mean age 68 years), selected arteries supplying the abdominal wall and back were injected with a lead oxide/gelatin contrast mixture. From these regions, 30 specimens were dissected free and imaged with a 16-slice spiral computed tomographic (CT) scanner. Using three-dimensional CT (3D-CT) angiography, reconstructions of the microvasculature of each specimen were produced and examined for their qualitative content. Two calibration tools were constructed to determine (1) the accuracy of linear measurements made with CT software tools, and (2) the smallest caliber blood vessel that is reliably represented on 3D-CT reconstructions. Three-dimensional CT angiography produced versatile, high quality angiograms of the microvasculature. Correlation between measurements made with electronic calipers and CT software tools was very high (Lin's concordance coefficient, 0.99 (95% CI 0.99-0.99)). The finest caliber of vessel reliably represented on the 3D-CT reconstructions was 0.4 mm internal diameter. In summary, 3D-CT angiography is a simple, accurate, and reproducible method that imparts a much improved perception of anatomy when compared with existing research methods. Measurement tools provide accurate quantitative data to aid vessel mapping and preoperative planning. Further work will be needed to explore the full utility of 3D-CT angiography in a clinical setting.

  16. Binary Colloidal Alloy Test-5: Three-Dimensional Melt

    NASA Technical Reports Server (NTRS)

    Yodh, Arjun G.

    2008-01-01

    Binary Colloidal Alloy Test - 5: Three-Dimensional Melt (BCAT-5-3DMelt) photographs initially randomized colloidal samples in microgravity to determine their resulting structure over time. BCAT-5-3D-Melt will allow the scientists to capture the kinetics (evolution) of their samples, as well as the final equilibrium state of each sample. BCAT-5-3D-Melt will look at the mechanisms of melting using three-dimensional temperature sensitive colloidal crystals. Results will help scientists develop fundamental physics concepts previously shadowed by the effects of gravity.

  17. Applications of three-dimensionally scanned models in orthodontics.

    PubMed

    Cha, B K; Choi, J I; Jost-Brinkmann, P G; Jeong, Y M

    2007-01-01

    The purpose of this study was to investigate clinical applications of the three-dimensional reverse engineering technologies for the analysis of orthodontic models. The measuring accuracy and the process of the 3D model scanning technique were evaluated with respect to linear, surface and volumetric parameters. Orthodontically induced dentoalveolar changes, which have been traditionally evaluated by cephalometric analysis, were assessed by the registration function of Rapidform 2002, a 3D-reverse modeling software in scanned maxillary casts. Three-dimensional digital models are valuable alternatives to conventional casts for model analysis and also yield information which could previously be gathered only by cephalometric superimposition.

  18. Accurate high-resolution measurements of 3-D tissue dynamics with registration-enhanced displacement encoded MRI.

    PubMed

    Gomez, Arnold D; Merchant, Samer S; Hsu, Edward W

    2014-06-01

    Displacement fields are important to analyze deformation, which is associated with functional and material tissue properties often used as indicators of health. Magnetic resonance imaging (MRI) techniques like DENSE and image registration methods like Hyperelastic Warping have been used to produce pixel-level deformation fields that are desirable in high-resolution analysis. However, DENSE can be complicated by challenges associated with image phase unwrapping, in particular offset determination. On the other hand, Hyperelastic Warping can be hampered by low local image contrast. The current work proposes a novel approach for measuring tissue displacement with both DENSE and Hyperelastic Warping, incorporating physically accurate displacements obtained by the latter to improve phase characterization in DENSE. The validity of the proposed technique is demonstrated using numerical and physical phantoms, and in vivo small animal cardiac MRI.

  19. Double calibration: an accurate, reliable and easy-to-use method for 3D scapular motion analysis.

    PubMed

    Brochard, Sylvain; Lempereur, Mathieu; Rémy-Néris, Olivier

    2011-02-24

    The most recent non-invasive methods for the recording of scapular motion are based on an acromion marker (AM) set and a single calibration (SC) of the scapula in a resting position. However, this method fails to accurately measure scapular kinematics above 90° of arm elevation, due to soft tissue artifacts of the skin and muscles covering the acromion. The aim of this study was to evaluate the accuracy, and inter-trial and inter-session repeatability of a double calibration method (DC) in comparison with SC. The SC and DC data were measured with an optoelectronic system during arm flexion and abduction at different angles of elevation (0-180°). They were compared with palpation of the scapula using a scapula locator. DC data was not significantly different from palpation for 5/6 axes of rotation tested (Y, X, and Z in abduction and flexion), where as SC showed significant differences for 5/6 axes. The root mean square errors ranged from 2.96° to 4.48° for DC and from 6° to 9.19° for SC. The inter-trial repeatability was good to excellent for SC and DC. The inter-session repeatability was moderate to excellent for SC and moderate to good for DC. Coupling AM and DC is an easy-to-use method, which yields accurate and reliable measurements of scapular kinematics for the complete range of arm motion. It can be applied to the measurement of shoulder motion in many fields (sports, orthopaedics, and rehabilitation), especially when large ranges of arm motion are required.

  20. Three-dimensional stellarator codes

    PubMed Central

    Garabedian, P. R.

    2002-01-01

    Three-dimensional computer codes have been used to develop quasisymmetric stellarators with modular coils that are promising candidates for a magnetic fusion reactor. The mathematics of plasma confinement raises serious questions about the numerical calculations. Convergence studies have been performed to assess the best configurations. Comparisons with recent data from large stellarator experiments serve to validate the theory. PMID:12140367

  1. Three dimensional colorimetric assay assemblies

    SciTech Connect

    Charych, D.; Reichart, A.

    2000-06-27

    A direct assay is described using novel three-dimensional polymeric assemblies which change from a blue to red color when exposed to an analyte, in one case a flu virus. The assemblies are typically in the form of liposomes which can be maintained in a suspension, and show great intensity in their color changes. Their method of production is also described.

  2. Three dimensional colorimetric assay assemblies

    DOEpatents

    Charych, Deborah; Reichart, Anke

    2000-01-01

    A direct assay is described using novel three-dimensional polymeric assemblies which change from a blue to red color when exposed to an analyte, in one case a flu virus. The assemblies are typically in the form of liposomes which can be maintained in a suspension, and show great intensity in their color changes. Their method of production is also described.

  3. Creating Three-Dimensional Scenes

    ERIC Educational Resources Information Center

    Krumpe, Norm

    2005-01-01

    Persistence of Vision Raytracer (POV-Ray), a free computer program for creating photo-realistic, three-dimensional scenes and a link for Mathematica users interested in generating POV-Ray files from within Mathematica, is discussed. POV-Ray has great potential in secondary mathematics classrooms and helps in strengthening students' visualization…

  4. Three-Dimensional Lissajous Figures.

    ERIC Educational Resources Information Center

    D'Mura, John M.

    1989-01-01

    Described is a mechanically driven device for generating three-dimensional harmonic space figures with different frequencies and phase angles on the X, Y, and Z axes. Discussed are apparatus, viewing stereo pairs, equations of motion, and using space figures in classroom. (YP)

  5. Magnetophotonic response of three-dimensional opals.

    PubMed

    Caicedo, José Manuel; Pascu, Oana; López-García, Martín; Canalejas, Víctor; Blanco, Alvaro; López, Cefe; Fontcuberta, Josep; Roig, Anna; Herranz, Gervasi

    2011-04-26

    Three-dimensional magnetophotonic crystals (3D-MPCs) are being postulated as appropriate platforms to tailor the magneto-optical spectral response of magnetic materials and to incorporate this functionality in a new generation of optical devices. By infiltrating self-assembled inverse opal structures with monodisperse nickel nanoparticles we have fabricated 3D-MPCs that show a sizable enhancement of the magneto-optical signal at frequencies around the stop-band edges of the photonic crystals. We have established a proper methodology to disentangle the intrinsic magneto-optical spectra from the nonmagnetic optical activity of the 3D-MPCs. The results of the optical and magneto-optical characterization are consistent with a homogeneous magnetic infiltration of the opal structure that gives rise to both a red-shift of the optical bandgap and a modification of the magneto-optical spectral response due to photonic bandgap effects. The results of our investigation demonstrate the potential of 3D-MPCs fabricated following the approach outlined here and offer opportunities to adapt the magneto-optical spectral response at optical frequencies by appropriate design of the opal structure or magnetic field strength.

  6. FRET Imaging in Three-dimensional Hydrogels

    PubMed Central

    Taboas, Juan M.

    2016-01-01

    Imaging of Förster resonance energy transfer (FRET) is a powerful tool for examining cell biology in real-time. Studies utilizing FRET commonly employ two-dimensional (2D) culture, which does not mimic the three-dimensional (3D) cellular microenvironment. A method to perform quenched emission FRET imaging using conventional widefield epifluorescence microscopy of cells within a 3D hydrogel environment is presented. Here an analysis method for ratiometric FRET probes that yields linear ratios over the probe activation range is described. Measurement of intracellular cyclic adenosine monophosphate (cAMP) levels is demonstrated in chondrocytes under forskolin stimulation using a probe for EPAC1 activation (ICUE1) and the ability to detect differences in cAMP signaling dependent on hydrogel material type, herein a photocrosslinking hydrogel (PC-gel, polyethylene glycol dimethacrylate) and a thermoresponsive hydrogel (TR-gel). Compared with 2D FRET methods, this method requires little additional work. Laboratories already utilizing FRET imaging in 2D can easily adopt this method to perform cellular studies in a 3D microenvironment. It can further be applied to high throughput drug screening in engineered 3D microtissues. Additionally, it is compatible with other forms of FRET imaging, such as anisotropy measurement and fluorescence lifetime imaging (FLIM), and with advanced microscopy platforms using confocal, pulsed, or modulated illumination. PMID:27500354

  7. Three-dimensional charge coupled device

    DOEpatents

    Conder, Alan D.; Young, Bruce K. F.

    1999-01-01

    A monolithic three dimensional charged coupled device (3D-CCD) which utilizes the entire bulk of the semiconductor for charge generation, storage, and transfer. The 3D-CCD provides a vast improvement of current CCD architectures that use only the surface of the semiconductor substrate. The 3D-CCD is capable of developing a strong E-field throughout the depth of the semiconductor by using deep (buried) parallel (bulk) electrodes in the substrate material. Using backside illumination, the 3D-CCD architecture enables a single device to image photon energies from the visible, to the ultra-violet and soft x-ray, and out to higher energy x-rays of 30 keV and beyond. The buried or bulk electrodes are electrically connected to the surface electrodes, and an E-field parallel to the surface is established with the pixel in which the bulk electrodes are located. This E-field attracts charge to the bulk electrodes independent of depth and confines it within the pixel in which it is generated. Charge diffusion is greatly reduced because the E-field is strong due to the proximity of the bulk electrodes.

  8. Three-Dimensional Imaging of Viral Infections.

    PubMed

    Risco, Cristina; de Castro, Isabel Fernández; Sanz-Sánchez, Laura; Narayan, Kedar; Grandinetti, Giovanna; Subramaniam, Sriram

    2014-11-01

    Three-dimensional (3D) imaging technologies are beginning to have significant impact in the field of virology, as they are helping us understand how viruses take control of cells. In this article we review several methodologies for 3D imaging of cells and show how these technologies are contributing to the study of viral infections and the characterization of specialized structures formed in virus-infected cells. We include 3D reconstruction by transmission electron microscopy (TEM) using serial sections, electron tomography, and focused ion beam scanning electron microscopy (FIB-SEM). We summarize from these methods selected contributions to our understanding of viral entry, replication, morphogenesis, egress and propagation, and changes in the spatial architecture of virus-infected cells. In combination with live-cell imaging, correlative microscopy, and new techniques for molecular mapping in situ, the availability of these methods for 3D imaging is expected to provide deeper insights into understanding the structural and dynamic aspects of viral infection.

  9. Feature-based three-dimensional registration for repetitive geometry in machine vision

    PubMed Central

    Gong, Yuanzheng; Seibel, Eric J.

    2016-01-01

    As an important step in three-dimensional (3D) machine vision, 3D registration is a process of aligning two or multiple 3D point clouds that are collected from different perspectives together into a complete one. The most popular approach to register point clouds is to minimize the difference between these point clouds iteratively by Iterative Closest Point (ICP) algorithm. However, ICP does not work well for repetitive geometries. To solve this problem, a feature-based 3D registration algorithm is proposed to align the point clouds that are generated by vision-based 3D reconstruction. By utilizing texture information of the object and the robustness of image features, 3D correspondences can be retrieved so that the 3D registration of two point clouds is to solve a rigid transformation. The comparison of our method and different ICP algorithms demonstrates that our proposed algorithm is more accurate, efficient and robust for repetitive geometry registration. Moreover, this method can also be used to solve high depth uncertainty problem caused by little camera baseline in vision-based 3D reconstruction.

  10. An Interactive Preprocessor Program with Graphics for a Three-Dimensional Finite Element Code.

    ERIC Educational Resources Information Center

    Hamilton, Claude Hayden, III

    The development and capabilities of an interactive preprocessor program with graphics for an existing three-dimensional finite element code is presented. This preprocessor program, EDGAP3D, is designed to be used in conjunction with the Texas Three Dimensional Grain Analysis Program (TXCAP3D). The code presented in this research is capable of the…

  11. UTILIZATION OF THREE-DIMENSIONAL INFORMATION IN ROAD CONSTRUCTION PROJECTS

    NASA Astrophysics Data System (ADS)

    Kubota, Satoshi

    In this research targeting road construction projects, schemes were investigated for utilizing three-dimensional (3D) data distributed in accordance with ISO (Internatio nal Organization for Standardization) and produced by 3D computer-aided design (CAD) software based on the concept of product data models. First, existing literature was classified by work stage as the context for utilizing 3D data. Next, the establishment of standards for exchanging 3D data, revising relevant systems, constructing road data models, realizing work process models, developing 3D CAD engines, and providing 3D data utilization environments are discussed, both as measures that should be undertaken and as future research topics for promoting the utilization of 3D data. Finally, the potential for utilizing 3D data in road construction projects by local government is examined, and the items to be implemented for this purpose are summarized.

  12. Nanoscale three-dimensional single particle tracking

    NASA Astrophysics Data System (ADS)

    Dupont, Aurélie; Lamb, Don C.

    2011-11-01

    Single particle tracking (SPT) in biological systems is a quickly growing field. Many new technologies are being developed providing new tracking capabilities, which also lead to higher demands and expectations for SPT. Following a single biomolecule as it performs its function provides quantitative mechanistic information that cannot be obtained in classical ensemble methods. From the 3D trajectory, information is available over the diffusional behavior of the particle and precise position information can also be used to elucidate interactions of the tracked particle with its surroundings. Thus, three-dimensional (3D) SPT is a very valuable tool for investigating cellular processes. This review presents recent progress in 3D SPT, from image-based techniques toward more sophisticated feedback approaches. We focus mainly on the feedback technique known as orbital tracking. We present here a modified version of the original orbital tracking in which the intensities from two z-planes are simultaneously measured allowing a concomitant wide-field imaging. The system can track single particles with a precision down to 5 nm in the x-y plane and 7 nm in the axial direction. The capabilities of the system are demonstrated using single virus tracing to follow the infection pathway of Prototype Foamy Virus in living cells.Single particle tracking (SPT) in biological systems is a quickly growing field. Many new technologies are being developed providing new tracking capabilities, which also lead to higher demands and expectations for SPT. Following a single biomolecule as it performs its function provides quantitative mechanistic information that cannot be obtained in classical ensemble methods. From the 3D trajectory, information is available over the diffusional behavior of the particle and precise position information can also be used to elucidate interactions of the tracked particle with its surroundings. Thus, three-dimensional (3D) SPT is a very valuable tool for

  13. Virtual three-dimensional blackboard: three-dimensional finger tracking with a single camera

    NASA Astrophysics Data System (ADS)

    Wu, Andrew; Hassan-Shafique, Khurram; Shah, Mubarak; da Vitoria Lobo, N.

    2004-01-01

    We present a method for three-dimensional (3D) tracking of a human finger from a monocular sequence of images. To recover the third dimension from the two-dimensional images, we use the fact that the motion of the human arm is highly constrained owing to the dependencies between elbow and forearm and the physical constraints on joint angles. We use these anthropometric constraints to derive a 3D trajectory of a gesticulating arm. The system is fully automated and does not require human intervention. The system presented can be used as a visualization tool, as a user-input interface, or as part of some gesture-analysis system in which 3D information is important.

  14. Three-dimensional mapping of microcircuit correlation structure

    PubMed Central

    Cotton, R. James; Froudarakis, Emmanouil; Storer, Patrick; Saggau, Peter; Tolias, Andreas S.

    2013-01-01

    Great progress has been made toward understanding the properties of single neurons, yet the principles underlying interactions between neurons remain poorly understood. Given that connectivity in the neocortex is locally dense through both horizontal and vertical connections, it is of particular importance to characterize the activity structure of local populations of neurons arranged in three dimensions. However, techniques for simultaneously measuring microcircuit activity are lacking. We developed an in vivo 3D high-speed, random-access two-photon microscope that is capable of simultaneous 3D motion tracking. This allows imaging from hundreds of neurons at several hundred Hz, while monitoring tissue movement. Given that motion will induce common artifacts across the population, accurate motion tracking is absolutely necessary for studying population activity with random-access based imaging methods. We demonstrate the potential of this imaging technique by measuring the correlation structure of large populations of nearby neurons in the mouse visual cortex, and find that the microcircuit correlation structure is stimulus-dependent. Three-dimensional random access multiphoton imaging with concurrent motion tracking provides a novel, powerful method to characterize the microcircuit activity in vivo. PMID:24133414

  15. Methods for analysis of cracks in three-dimensional solids

    NASA Technical Reports Server (NTRS)

    Raju, I. S.; Newman, J. C., Jr.

    1984-01-01

    Various analytical and numerical methods used to evaluate the stress intensity factors for cracks in three-dimensional (3-D) solids are reviewed. Classical exact solutions and many of the approximate methods used in 3-D analyses of cracks are reviewed. The exact solutions for embedded elliptic cracks in infinite solids are discussed. The approximate methods reviewed are the finite element methods, the boundary integral equation (BIE) method, the mixed methods (superposition of analytical and finite element method, stress difference method, discretization-error method, alternating method, finite element-alternating method), and the line-spring model. The finite element method with singularity elements is the most widely used method. The BIE method only needs modeling of the surfaces of the solid and so is gaining popularity. The line-spring model appears to be the quickest way to obtain good estimates of the stress intensity factors. The finite element-alternating method appears to yield the most accurate solution at the minimum cost.

  16. On the Use of Uavs in Mining and Archaeology - Geo-Accurate 3d Reconstructions Using Various Platforms and Terrestrial Views

    NASA Astrophysics Data System (ADS)

    Tscharf, A.; Rumpler, M.; Fraundorfer, F.; Mayer, G.; Bischof, H.

    2015-08-01

    During the last decades photogrammetric computer vision systems have been well established in scientific and commercial applications. Especially the increasing affordability of unmanned aerial vehicles (UAVs) in conjunction with automated multi-view processing pipelines have resulted in an easy way of acquiring spatial data and creating realistic and accurate 3D models. With the use of multicopter UAVs, it is possible to record highly overlapping images from almost terrestrial camera positions to oblique and nadir aerial images due to the ability to navigate slowly, hover and capture images at nearly any possible position. Multi-copter UAVs thus are bridging the gap between terrestrial and traditional aerial image acquisition and are therefore ideally suited to enable easy and safe data collection and inspection tasks in complex or hazardous environments. In this paper we present a fully automated processing pipeline for precise, metric and geo-accurate 3D reconstructions of complex geometries using various imaging platforms. Our workflow allows for georeferencing of UAV imagery based on GPS-measurements of camera stations from an on-board GPS receiver as well as tie and control point information. Ground control points (GCPs) are integrated directly in the bundle adjustment to refine the georegistration and correct for systematic distortions of the image block. We discuss our approach based on three different case studies for applications in mining and archaeology and present several accuracy related analyses investigating georegistration, camera network configuration and ground sampling distance. Our approach is furthermore suited for seamlessly matching and integrating images from different view points and cameras (aerial and terrestrial as well as inside views) into one single reconstruction. Together with aerial images from a UAV, we are able to enrich 3D models by combining terrestrial images as well inside views of an object by joint image processing to

  17. A technique for evaluating bone ingrowth into 3D printed, porous Ti6Al4V implants accurately using X-ray micro-computed tomography and histomorphometry.

    PubMed

    Palmquist, Anders; Shah, Furqan A; Emanuelsson, Lena; Omar, Omar; Suska, Felicia

    2017-03-01

    This paper investigates the application of X-ray micro-computed tomography (micro-CT) to accurately evaluate bone formation within 3D printed, porous Ti6Al4V implants manufactured using Electron Beam Melting (EBM), retrieved after six months of healing in sheep femur and tibia. All samples were scanned twice (i.e., before and after resin embedding), using fast, low-resolution scans (Skyscan 1172; Bruker micro-CT, Kontich, Belgium), and were analysed by 2D and 3D morphometry. The main questions posed were: (i) Can low resolution, fast scans provide morphometric data of bone formed inside (and around) metal implants with a complex, open-pore architecture?, (ii) Can micro-CT be used to accurately quantify both the bone area (BA) and bone-implant contact (BIC)?, (iii) What degree of error is introduced in the quantitative data by varying the threshold values?, and (iv) Does resin embedding influence the accuracy of the analysis? To validate the accuracy of micro-CT measurements, each data set was correlated with a corresponding centrally cut histological section. The results show that quantitative histomorphometry corresponds strongly with 3D measurements made by micro-CT, where a high correlation exists between the two techniques for bone area/volume measurements around and inside the porous network. On the contrary, the direct bone-implant contact is challenging to estimate accurately or reproducibly. Large errors may be introduced in micro-CT measurements when segmentation is performed without calibrating the data set against a corresponding histological section. Generally, the bone area measurement is strongly influenced by the lower threshold limit, while the upper threshold limit has little or no effect. Resin embedding does not compromise the accuracy of micro-CT measurements, although there is a change in the contrast distributions and optimisation of the threshold ranges is required.

  18. Reconstruction of three-dimensional grain structure in polycrystalline iron via an interactive segmentation method

    NASA Astrophysics Data System (ADS)

    Feng, Min-nan; Wang, Yu-cong; Wang, Hao; Liu, Guo-quan; Xue, Wei-hua

    2017-03-01

    Using a total of 297 segmented sections, we reconstructed the three-dimensional (3D) structure of pure iron and obtained the largest dataset of 16254 3D complete grains reported to date. The mean values of equivalent sphere radius and face number of pure iron were observed to be consistent with those of Monte Carlo simulated grains, phase-field simulated grains, Ti-alloy grains, and Ni-based super alloy grains. In this work, by finding a balance between automatic methods and manual refinement, we developed an interactive segmentation method to segment serial sections accurately in the reconstruction of the 3D microstructure; this approach can save time as well as substantially eliminate errors. The segmentation process comprises four operations: image preprocessing, breakpoint detection based on mathematical morphology analysis, optimized automatic connection of the breakpoints, and manual refinement by artificial evaluation.

  19. Formation of spatially and geometrically controlled three-dimensional tissues in soft gels by sacrificial micromolding.

    PubMed

    Cerchiari, Alec; Garbe, James C; Todhunter, Michael E; Jee, Noel Y; Pinney, James R; LaBarge, Mark A; Desai, Tejal A; Gartner, Zev J

    2015-06-01

    Patterned three-dimensional (3D) cell culture models aim to more accurately represent the in vivo architecture of a tissue for the purposes of testing drugs, studying multicellular biology, or engineering functional tissues. However, patterning 3D multicellular structures within very soft hydrogels (<500 Pa) that mimic the physicochemical environment of many tissues remains a challenge for existing methods. To overcome this challenge, we use a Sacrificial Micromolding technique to temporarily form spatially and geometrically defined 3D cell aggregates in degradable scaffolds before transferring and culturing them in a reconstituted extracellular matrix. Herein, we demonstrate that Sacrificial Micromolding (1) promotes cyst formation and proper polarization of established epithelial cell lines, (2) allows reconstitution of heterotypic cell-cell interactions in multicomponent epithelia, and (3) can be used to control the lumenization-state of epithelial cysts as a function of tissue size. In addition, we discuss the potential of Sacrificial Micromolding as a cell-patterning tool for future studies.

  20. Three-dimensional multislice helical computed tomography techniques for canine extra-hepatic portosystemic shunt assessment.

    PubMed

    Bertolini, Giovanna; Rolla, Edoardo C; Zotti, Alessandro; Caldin, Marco

    2006-01-01

    The purpose of the present study was to investigate the feasibility and usefulness of three-dimensional (3D) multislice computed tomography (CT) angiography with maximum intensity projection (MIP) and volume rendering (VR) in six dogs with clinical and sonographic findings suggestive of portosystemic shunt. Furthermore, we aimed to estimate the diameter of the portal vein and shunt vessels. MIP and VR reconstructions were performed for each patient and the origin and insertion of all shunt vessels were detected. In addition, 3D reconstructions allowed excellent depiction of vascular morphology and topography. All diagnoses and vessel measurements were confirmed by surgery. 3D multidetector CT angiography is a promising, noninvasive, and accurate method of evaluating dogs with suspected portosystemic shunts.

  1. Two-dimensional versus three-dimensional cell counting: a practical perspective.

    PubMed

    Benes, F M; Lange, N

    2001-01-01

    In recent years, it has been argued by some neuroanatomists that three-dimensional (3-D) counting approaches must be used in studies of neural systems, so that 'unbiased' counts of neurons can be obtained. By contrast, two-dimensional (2-D) cell-counting methods are said to be 'assumption-based' and to yield inaccurate results. Working from the premise that all scientific methodologies are assumption-based and suffer from inherent biases, the current review considers the relative strengths and weaknesses of 2-D versus 3-D counting approaches. This comparison is from the standpoint of predictive performance with respect to bias, variance and fidelity to the actual spatial arrangements of cells in the tissue under study. When these considerations are taken, together with the human resources that are required in using either methodology, 2-D methods offer more practical alternatives that might even provide more scientifically accurate estimates compared with their 3-D counterparts.

  2. Three-Dimensional Printing: An Enabling Technology for IR.

    PubMed

    Sheth, Rahul; Balesh, Elie R; Zhang, Yu Shrike; Hirsch, Joshua A; Khademhosseini, Ali; Oklu, Rahmi

    2016-06-01

    Rapid prototyping, also known as three-dimensional (3D) printing, is a recent technologic advancement with tremendous potential for advancing medical device design. A wide range of raw materials can be incorporated into complex 3D structures, including plastics, metals, biocompatible polymers, and even living cells. With its promise of highly customized, adaptable, and personalized device design at the point of care, 3D printing stands to revolutionize medical care. The present review summarizes the methods for 3D printing and their current and potential roles in medical device design, with an emphasis on their potential relevance to interventional radiology.

  3. Predicting three-dimensional patellofemoral kinematics from static imaging-based alignment measures.

    PubMed

    Freedman, Benjamin R; Sheehan, Frances T

    2013-03-01

    Patellofemoral pain syndrome causes significant discomfort and disability among much of the general population. Despite recent breakthroughs in dynamic three-dimensional imaging technologies to assess pathological patellofemoral motion, such tools remain costly for clinical diagnostics applications. Thus, this study investigated whether three-dimensional patellofemoral kinematics could be predicted from routine two-dimensional static measures of patellofemoral joint alignment quantified from magnetic resonance imaging (MRI) data acquired in full knee extension. Twenty-six volunteers clinically diagnosed with patellofemoral pain (19 F/7 M, 25.9 ± 11.1 years) and 26 control subjects (19 F/7 M, 25.3 ± 7.7 years) were included in this IRB-approved study. Static three-dimensional sagittal T1-weighted gradient recall echo and dynamic MRI scans were acquired. For the dynamic image acquisition, subjects cyclically flexed and extended their knee (at 30 cycles/min) while a full cine-phase contrast MRI set (24 time frames of anatomic images and x-, y-, and z-velocity images) was acquired. From these data, static measures of patellofemoral alignment and three-dimensional patellofemoral kinematics were derived. Single and multiple regressions between static and kinematic variables were evaluated. Although shown reliable, the static MRI measures could only partially predict patellofemoral kinematics, with r(2) -values ranging from 16% to 77%. This makes it imperitave that the current precise, accurate, 3D, dynamic imaging techniques be translated into clinical tools.

  4. Determination of left ventricular volume, ejection fraction, and myocardial mass by real-time three-dimensional echocardiography

    NASA Technical Reports Server (NTRS)

    Qin, J. X.; Shiota, T.; Thomas, J. D.

    2000-01-01

    Reconstructed three-dimensional (3-D) echocardiography is an accurate and reproducible method of assessing left ventricular (LV) functions. However, it has limitations for clinical study due to the requirement of complex computer and echocardiographic analysis systems, electrocardiographic/respiratory gating, and prolonged imaging times. Real-time 3-D echocardiography has a major advantage of conveniently visualizing the entire cardiac anatomy in three dimensions and of potentially accurately quantifying LV volumes, ejection fractions, and myocardial mass in patients even in the presence of an LV aneurysm. Although the image quality of the current real-time 3-D echocardiographic methods is not optimal, its widespread clinical application is possible because of the convenient and fast image acquisition. We review real-time 3-D echocardiographic image acquisition and quantitative analysis for the evaluation of LV function and LV mass.

  5. 3-D Mesh Generation Nonlinear Systems

    SciTech Connect

    Christon, M. A.; Dovey, D.; Stillman, D. W.; Hallquist, J. O.; Rainsberger, R. B

    1994-04-07

    INGRID is a general-purpose, three-dimensional mesh generator developed for use with finite element, nonlinear, structural dynamics codes. INGRID generates the large and complex input data files for DYNA3D, NIKE3D, FACET, and TOPAZ3D. One of the greatest advantages of INGRID is that virtually any shape can be described without resorting to wedge elements, tetrahedrons, triangular elements or highly distorted quadrilateral or hexahedral elements. Other capabilities available are in the areas of geometry and graphics. Exact surface equations and surface intersections considerably improve the ability to deal with accurate models, and a hidden line graphics algorithm is included which is efficient on the most complicated meshes. The primary new capability is associated with the boundary conditions, loads, and material properties required by nonlinear mechanics programs. Commands have been designed for each case to minimize user effort. This is particularly important since special processing is almost always required for each load or boundary condition.

  6. Three-dimensional perspective visualization

    NASA Technical Reports Server (NTRS)

    Hussey, Kevin

    1991-01-01

    It was demonstrated that image processing computer graphic techniques can provide an effective means of physiographic analysis of remotely sensed regions through the use of three-dimensional perspective rendering. THe methods used to simulate and animate three-dimensional surfaces from two-dimensional imagery and digital elevation models are explained. A brief historic look at JPL's efforts in this field and several examples of animations, illustrating the evolution of these techniques from 1985, are shown. JPL's current research in this area is discussed along with examples of technology transfer and potential commercial application. The software is part of the VICAR (Video Image Communication and Retrieval) image processing system which was developed at the Multimission Image Processing Laboratory of JPL.

  7. Three-dimensional compressible and stretchable conductive composites.

    PubMed

    Yu, You; Zeng, Jifang; Chen, Chaojian; Xie, Zhuang; Guo, Ruisheng; Liu, Zhilu; Zhou, Xuechang; Yang, Yong; Zheng, Zijian

    2014-02-01

    Three-dimensional (3D) conductive composites with remarkable flexibility, compressibility, and stretchability are fabricated by solution deposition of thin metal coatings on chemically modified, macroscopically continuous, 3D polyurethane sponges, followed by infiltration of the metallic sponges with polydimethylsiloxane (PDMS). These low-cost conductive composites are used as high-performance interconnects for flexible and stretchable light-emitting diode (LED) arrays, even with severe surface abrasion or cutting.

  8. Three-Dimensional DNA Nanostructures Assembled from DNA Star Motifs.

    PubMed

    Tian, Cheng; Zhang, Chuan

    2017-01-01

    Tile-based DNA self-assembly is a promising method in DNA nanotechnology and has produced a wide range of nanostructures by using a small set of unique DNA strands. DNA star motif, as one of DNA tiles, has been employed to assemble varieties of symmetric one-, two-, three-dimensional (1, 2, 3D) DNA nanostructures. Herein, we describe the design principles, assembly methods, and characterization methods of 3D DNA nanostructures assembled from the DNA star motifs.

  9. Mass spectrometry imaging of therapeutics from animal models to three-dimensional cell cultures.

    PubMed

    Liu, Xin; Hummon, Amanda B

    2015-10-06

    Mass spectrometry imaging (MSI) is a powerful label-free technique for the investigation of the spatial distribution of molecules at complex surfaces and has been widely used in the pharmaceutical sciences to understand the distribution of different drugs and their metabolites in various biological samples, ranging from cell-based models to tissues. Here, we review the current applications of MSI for drug studies in animal models, followed by a discussion of the novel advances of MSI in three-dimensional (3D) cell cultures for accurate, efficient, and high-throughput analyses to evaluate therapeutics.

  10. Mass Spectrometry Imaging of Therapeutics from Animal Models to Three-Dimensional Cell Cultures

    PubMed Central

    Liu, Xin; Hummon, Amanda B.

    2016-01-01

    Mass spectrometry imaging (MSI) is a powerful label-free technique for the investigation of the spatial distribution of molecules at complex surfaces and has been widely used in the pharmaceutical sciences to understand the distribution of different drugs and their metabolites in various biological samples, ranging from cell-based models to tissues. Here, we review the current applications of MSI for drug studies in animal models, followed by a discussion of the novel advances of MSI in three-dimensional (3D) cell cultures for accurate, efficient and high-throughput analyses to evaluate therapeutics. PMID:26084404

  11. Estimating Three-Dimensional Orientation of Human Body Parts by Inertial/Magnetic Sensing

    PubMed Central

    Sabatini, Angelo Maria

    2011-01-01

    User-worn sensing units composed of inertial and magnetic sensors are becoming increasingly popular in various domains, including biomedical engineering, robotics, virtual reality, where they can also be applied for real-time tracking of the orientation of human body parts in the three-dimensional (3D) space. Although they are a promising choice as wearable sensors under many respects, the inertial and magnetic sensors currently in use offer measuring performance that are critical in order to achieve and maintain accurate 3D-orientation estimates, anytime and anywhere. This paper reviews the main sensor fusion and filtering techniques proposed for accurate inertial/magnetic orientation tracking of human body parts; it also gives useful recipes for their actual implementation. PMID:22319365

  12. Estimating three-dimensional orientation of human body parts by inertial/magnetic sensing.

    PubMed

    Sabatini, Angelo Maria

    2011-01-01

    User-worn sensing units composed of inertial and magnetic sensors are becoming increasingly popular in various domains, including biomedical engineering, robotics, virtual reality, where they can also be applied for real-time tracking of the orientation of human body parts in the three-dimensional (3D) space. Although they are a promising choice as wearable sensors under many respects, the inertial and magnetic sensors currently in use offer measuring performance that are critical in order to achieve and maintain accurate 3D-orientation estimates, anytime and anywhere. This paper reviews the main sensor fusion and filtering techniques proposed for accurate inertial/magnetic orientation tracking of human body parts; it also gives useful recipes for their actual implementation.

  13. A microsphere assembly method with laser microwelding for fabrication of three-dimensional periodic structures

    NASA Astrophysics Data System (ADS)

    Takagi, Kenta; Omote, Masanori; Kawasaki, Akira

    2010-03-01

    The orderly build-up of monosized microspheres with sizes of hundreds of micrometres enabled us to develop three-dimensional (3D) photonic crystal devices for terahertz electromagnetic waves. We designed and manufactured an original 3D particle assembly system capable of fabricating arbitrary periodic structures from these spherical particles. This method employs a pick-and-place assembling approach with robotic manipulation and interparticle laser microwelding in order to incorporate a contrivance for highly accurate arraying: an operation that compensates the size deviation of raw monosized particles. Pre-examination of particles of various materials revealed that interparticle laser welding must be achieved with local melting by suppressing heat diffusion from the welding area. By optimizing the assembly conditions, we succeeded in fabricating an accurate periodic structure with a diamond lattice from 400 µm polyethylene composite particles. This structure demonstrated a photonic bandgap in the terahertz frequency range.

  14. Applications of three-dimensional printing technology in urological practice.

    PubMed

    Youssef, Ramy F; Spradling, Kyle; Yoon, Renai; Dolan, Benjamin; Chamberlin, Joshua; Okhunov, Zhamshid; Clayman, Ralph; Landman, Jaime

    2015-11-01

    A rapid expansion in the medical applications of three-dimensional (3D)-printing technology has been seen in recent years. This technology is capable of manufacturing low-cost and customisable surgical devices, 3D models for use in preoperative planning and surgical education, and fabricated biomaterials. While several studies have suggested 3D printers may be a useful and cost-effective tool in urological practice, few studies are available that clearly demonstrate the clinical benefit of 3D-printed materials. Nevertheless, 3D-printing technology continues to advance rapidly and promises to play an increasingly larger role in the field of urology. Herein, we review the current urological applications of 3D printing and discuss the potential impact of 3D-printing technology on the future of urological practice.

  15. Three-dimensional vertex model for simulating multicellular morphogenesis

    PubMed Central

    Okuda, Satoru; Inoue, Yasuhiro; Adachi, Taiji

    2015-01-01

    During morphogenesis, various cellular activities are spatiotemporally coordinated on the protein regulatory background to construct the complicated, three-dimensional (3D) structures of organs. Computational simulations using 3D vertex models have been the focus of efforts to approach the mechanisms underlying 3D multicellular constructions, such as dynamics of the 3D monolayer or multilayer cell sheet like epithelia as well as the 3D compacted cell aggregate, including dynamic changes in layer structures. 3D vertex models enable the quantitative simulation of multicellular morphogenesis on the basis of single-cell mechanics, with complete control of various cellular activities such as cell contraction, growth, rearrangement, division, and death. This review describes the general use of the 3D vertex model, along with its applications to several simplified problems of developmental phenomena. PMID:27493850

  16. Watermarking of three-dimensional objects by digital holography

    NASA Astrophysics Data System (ADS)

    Kishk, Sherif; Javidi, Bahram

    2003-02-01

    We present an optical method for information watermarking of three-dimensional (3D) objects by digital holography. A hidden image is embedded by double phase encoding in a phase-shift digital hologram of the 3D object. We decode the watermarked hologram to reconstruct the hidden image and the 3D object. We use either the entire hologram or a part of it to decode the hidden image. Experiments are presented to illustrate the ability to recover both the 3D object and the decoded hidden image. Digital holograms of the 3D object are obtained by optical experiments. The watermarking process, 3D object reconstruction, and hidden image recovery are performed digitally. To the best of our knowledge, this is the first report of 3D object watermarking by use of a phase encoding technique and digital holography.

  17. Three-dimensional Printing in the Intestine.

    PubMed

    Wengerter, Brian C; Emre, Gulus; Park, Jea Young; Geibel, John

    2016-08-01

    Intestinal transplantation remains a life-saving option for patients with severe intestinal failure. With the advent of advanced tissue engineering techniques, great strides have been made toward manufacturing replacement tissues and organs, including the intestine, which aim to avoid transplant-related complications. The current paradigm is to seed a biocompatible support material (scaffold) with a desired cell population to generate viable replacement tissue. Although this technique has now been extended by the three-dimensional (3D) printing of geometrically complex scaffolds, the overall approach is hindered by relatively slow turnover and negative effects of residual scaffold material, which affects final clinical outcome. Methods recently developed for scaffold-free 3D bioprinting may overcome such obstacles and should allow for rapid manufacture and deployment of "bioprinted organs." Much work remains before 3D bioprinted tissues can enter clinical use. In this brief review we examine the present state and future perspectives of this nascent technology before full clinical implementation.

  18. Three-dimensional landing zone ladar

    NASA Astrophysics Data System (ADS)

    Savage, James; Goodrich, Shawn; Burns, H. N.

    2016-05-01

    Three-Dimensional Landing Zone (3D-LZ) refers to a series of Air Force Research Laboratory (AFRL) programs to develop high-resolution, imaging ladar to address helicopter approach and landing in degraded visual environments with emphasis on brownout; cable warning and obstacle avoidance; and controlled flight into terrain. Initial efforts adapted ladar systems built for munition seekers, and success led to a the 3D-LZ Joint Capability Technology Demonstration (JCTD) , a 27-month program to develop and demonstrate a ladar subsystem that could be housed with the AN/AAQ-29 FLIR turret flown on US Air Force Combat Search and Rescue (CSAR) HH-60G Pave Hawk helicopters. Following the JCTD flight demonstration, further development focused on reducing size, weight, and power while continuing to refine the real-time geo-referencing, dust rejection, obstacle and cable avoidance, and Helicopter Terrain Awareness and Warning (HTAWS) capability demonstrated under the JCTD. This paper summarizes significant ladar technology development milestones to date, individual LADAR technologies within 3D-LZ, and results of the flight testing.

  19. Three-dimensional visualization for large models

    NASA Astrophysics Data System (ADS)

    Roth, Michael W.

    2001-09-01

    High-resolution (0.3-1 m) digital-elevation data is widely available from commercial sources. Whereas the production of two-dimensional (2D) mapping products from such data is standard practice, the visualization of such three-dimensional (3D) data has been problematic. The basis for this problem is the same as that for the large-model problem in computer graphics-- large amounts of geometry are difficult for current rendering algorithms and hardware. This paper describes a cost-effective solution to this problem that has two parts. First is the employment of the latest in cost-effective 3D chips and video boards that have recently emerged. The second part is the employment of quad-tree data structures for efficient data storage and retrieval during rendering. The result is the capability for real-time display of large (over tens of millions of samples) digital elevation models on modest PC-based systems. This paper shows several demonstrations of this approach using airborne lidar data. The implication of this work is a paradigm shift for geo-spatial information systems--3D data can now be as easy to use as 2D data.

  20. Combining Public Domain and Professional Panoramic Imagery for the Accurate and Dense 3d Reconstruction of the Destroyed Bel Temple in Palmyra

    NASA Astrophysics Data System (ADS)

    Wahbeh, W.; Nebiker, S.; Fangi, G.

    2016-06-01

    This paper exploits the potential of dense multi-image 3d reconstruction of destroyed cultural heritage monuments by either using public domain touristic imagery only or by combining the public domain imagery with professional panoramic imagery. The focus of our work is placed on the reconstruction of the temple of Bel, one of the Syrian heritage monuments, which was destroyed in September 2015 by the so called "Islamic State". The great temple of Bel is considered as one of the most important religious buildings of the 1st century AD in the East with a unique design. The investigations and the reconstruction were carried out using two types of imagery. The first are freely available generic touristic photos collected from the web. The second are panoramic images captured in 2010 for documenting those monuments. In the paper we present a 3d reconstruction workflow for both types of imagery using state-of-the art dense image matching software, addressing the non-trivial challenges of combining uncalibrated public domain imagery with panoramic images with very wide base-lines. We subsequently investigate the aspects of accuracy and completeness obtainable from the public domain touristic images alone and from the combination with spherical panoramas. We furthermore discuss the challenges of co-registering the weakly connected 3d point cloud fragments resulting from the limited coverage of the touristic photos. We then describe an approach using spherical photogrammetry as a virtual topographic survey allowing the co-registration of a detailed and accurate single 3d model of the temple interior and exterior.

  1. The current state of the art in three dimensional oncologic imaging: An overview

    SciTech Connect

    Kuszyk, B.S.; Ney, D.R.; Fishman, E.K.

    1995-12-01

    To provide an overview of the methods and clinical applications of three dimensional (3D) medical imaging in the oncologic patient, we briefly outline the techniques currently used to create 3D medical images with an emphasis on their strengths and shortcomings as they relate to oncologic imaging and radiation therapy planning. We then discuss some of the most important and promising oncologic applications of 3D imaging and suggest likely future directions in this rapidly developing field. Since the first application of 3D techniques to medical data over a decade ago, 3D medical images have evolved from relatively crude representations of musculoskeletal abnormalities to detailed and accurate representations of a variety of soft tissue, vascular, and oncologic pathology. The rapid development of both computer hardware and software coupled with the application of 3D techniques to a variety of imaging modalities have expanded the clinical applications of this technology dramatically. 3D medical images are clinically practical tools for oncologic evaluation and effective radiation therapy planning. 79 refs., 5 figs.

  2. THE THREE-DIMENSIONAL EVOLUTION TO CORE COLLAPSE OF A MASSIVE STAR

    SciTech Connect

    Couch, Sean M.; Chatzopoulos, Emmanouil; Arnett, W. David; Timmes, F. X.

    2015-07-20

    We present the first three-dimensional (3D) simulation of the final minutes of iron core growth in a massive star, up to and including the point of core gravitational instability and collapse. We capture the development of strong convection driven by violent Si burning in the shell surrounding the iron core. This convective burning builds the iron core to its critical mass and collapse ensues, driven by electron capture and photodisintegration. The non-spherical structure and motion generated by 3D convection is substantial at the point of collapse, with convective speeds of several hundreds of km s{sup −1}. We examine the impact of such physically realistic 3D initial conditions on the core-collapse supernova mechanism using 3D simulations including multispecies neutrino leakage and find that the enhanced post-shock turbulence resulting from 3D progenitor structure aids successful explosions. We conclude that non-spherical progenitor structure should not be ignored, and should have a significant and favorable impact on the likelihood for neutrino-driven explosions. In order to make simulating the 3D collapse of an iron core feasible, we were forced to make approximations to the nuclear network making this effort only a first step toward accurate, self-consistent 3D stellar evolution models of the end states of massive stars.

  3. Computer Generated Holography as a Three-Dimensional Display Medium

    DTIC Science & Technology

    1990-12-01

    series of two dimensional images are reflected on an object screen resulting in an autostereoscopic , or true three dimensional, images. The advantages of...an attractive target to optimize. Jack Ritter has suggested a fast approximation to 3D Euclidean distance calculations (10:432). His methid uses no

  4. Development of Three-Dimensional Object Completion in Infancy

    ERIC Educational Resources Information Center

    Soska, Kasey C.; Johnson, Scott P.

    2008-01-01

    Three-dimensional (3D) object completion was investigated by habituating 4- and 6-month-old infants (n = 24 total) with a computer-generated wedge stimulus that pivoted 15[degrees], providing only a limited view. Two displays, rotating 360[degrees], were then shown: a complete, solid volume and an incomplete, hollow form composed only of the sides…

  5. A Novel Three-Dimensional Tool for Teaching Human Neuroanatomy

    ERIC Educational Resources Information Center

    Estevez, Maureen E.; Lindgren, Kristen A.; Bergethon, Peter R.

    2010-01-01

    Three-dimensional (3D) visualization of neuroanatomy can be challenging for medical students. This knowledge is essential in order for students to correlate cross-sectional neuroanatomy and whole brain specimens within neuroscience curricula and to interpret clinical and radiological information as clinicians or researchers. This study implemented…

  6. Integration of Computed Tomography and Three-Dimensional Echocardiography for Hybrid Three-Dimensional Printing in Congenital Heart Disease.

    PubMed

    Gosnell, Jordan; Pietila, Todd; Samuel, Bennett P; Kurup, Harikrishnan K N; Haw, Marcus P; Vettukattil, Joseph J

    2016-12-01

    Three-dimensional (3D) printing is an emerging technology aiding diagnostics, education, and interventional, and surgical planning in congenital heart disease (CHD). Three-dimensional printing has been derived from computed tomography, cardiac magnetic resonance, and 3D echocardiography. However, individually the imaging modalities may not provide adequate visualization of complex CHD. The integration of the strengths of two or more imaging modalities has the potential to enhance visualization of cardiac pathomorphology. We describe the feasibility of hybrid 3D printing from two imaging modalities in a patient with congenitally corrected transposition of the great arteries (L-TGA). Hybrid 3D printing may be useful as an additional tool for cardiologists and cardiothoracic surgeons in planning interventions in children and adults with CHD.

  7. AAOGlimpse: Three-dimensional Data Viewer

    NASA Astrophysics Data System (ADS)

    Shortridge, Keith

    2011-10-01

    AAOGlimpse is an experimental display program that uses OpenGL to display FITS data (and even JPEG images) as 3D surfaces that can be rotated and viewed from different angles, all in real-time. It is WCS-compliant and designed to handle three-dimensional data. Each plane in a data cube is surfaced in the same way, and the program allows the user to travel through a cube by 'peeling off' successive planes, or to look into a cube by suppressing the display of data below a given cutoff value. It can blink images and can superimpose images and contour maps from different sources using their world coordinate data. A limited socket interface allows communication with other programs.

  8. Three-dimensional modeling of the human fallopian tube fimbriae

    PubMed Central

    Eddie, Sharon L.; Quartuccio, Suzanne M.; Zhu, Jie; Shepherd, Jessica A.; Kothari, Rajul; Kim, J. Julie; Woodruff, Teresa K.; Burdette, Joanna E.

    2015-01-01

    Objective Ovarian cancer is the most lethal gynecological malignancy that affects women. Recent data suggests the disease may originate in the fallopian fimbriae; however, the anatomical origin of ovarian carcinogenesis remains unclear. This is largely driven by our lack of knowledge regarding the structure and function of normal fimbriae and the relative paucity of models that accurately recapitulate the in vivo fallopian tube. Therefore, a human three-dimensional (3D) culture system was developed to examine the role of the fallopian fimbriae in serous tumorigenesis. Methods Alginate matrix was utilized to support human fallopian fimbriae ex vivo. Fimbriae were cultured with factors hypothesized to contribute to carcinogenesis, namely; H2O2 (1mM) a mimetic of oxidative stress, insulin (5 µg/ml) to stimulate glycolysis, and estradiol (E2, 10nM) which peaks before ovulation. Cultures were evaluated for changes in proliferation and p53 expression, criteria utilized to identify potential precursor lesions. Further, secretory factors were assessed after treatment with E2 to identify if steroid signaling induces a pro-tumorigenic microenvironment. Results 3D fimbriae cultures maintained normal tissue architecture up to 7 days, retaining both epithelial subtypes. Treatment of cultures with H2O2 or insulin significantly induced proliferation. However, p53 stabilization was unaffected by any particular treatment, although was induced by ex vivo culturing. Moreover, E2-alone treatment significantly induced its canonical target PR and expression of IL8, a factor linked to poor outcome. Conclusions 3D alginate cultures of human fallopian fimbriae provide an important microphysicological model, which can be further utilized to investigate serous tumorigenesis originating from the fallopian tube. PMID:25527363

  9. Three-dimensional tissue assemblies: novel models for the study of Salmonella enterica serovar Typhimurium pathogenesis

    NASA Technical Reports Server (NTRS)

    Nickerson, C. A.; Goodwin, T. J.; Terlonge, J.; Ott, C. M.; Buchanan, K. L.; Uicker, W. C.; Emami, K.; LeBlanc, C. L.; Ramamurthy, R.; Clarke, M. S.; Vanderburg, C. R.; Hammond, T.; Pierson, D. L.

    2001-01-01

    The lack of readily available experimental systems has limited knowledge pertaining to the development of Salmonella-induced gastroenteritis and diarrheal disease in humans. We used a novel low-shear stress cell culture system developed at the National Aeronautics and Space Administration in conjunction with cultivation of three-dimensional (3-D) aggregates of human intestinal tissue to study the infectivity of Salmonella enterica serovar Typhimurium for human intestinal epithelium. Immunohistochemical characterization and microscopic analysis of 3-D aggregates of the human intestinal epithelial cell line Int-407 revealed that the 3-D cells more accurately modeled human in vivo differentiated tissues than did conventional monolayer cultures of the same cells. Results from infectivity studies showed that Salmonella established infection of the 3-D cells in a much different manner than that observed for monolayers. Following the same time course of infection with Salmonella, 3-D Int-407 cells displayed minimal loss of structural integrity compared to that of Int-407 monolayers. Furthermore, Salmonella exhibited significantly lower abilities to adhere to, invade, and induce apoptosis of 3-D Int-407 cells than it did for infected Int-407 monolayers. Analysis of cytokine expression profiles of 3-D Int-407 cells and monolayers following infection with Salmonella revealed significant differences in expression of interleukin 1alpha (IL-1alpha), IL-1beta, IL-6, IL-1Ra, and tumor necrosis factor alpha mRNAs between the two cultures. In addition, uninfected 3-D Int-407 cells constitutively expressed higher levels of transforming growth factor beta1 mRNA and prostaglandin E2 than did uninfected Int-407 monolayers. By more accurately modeling many aspects of human in vivo tissues, the 3-D intestinal cell model generated in this study offers a novel approach for studying microbial infectivity from the perspective of the host-pathogen interaction.

  10. Quasicrystalline three-dimensional foams

    NASA Astrophysics Data System (ADS)

    Cox, S. J.; Graner, F.; Mosseri, R.; Sadoc, J.-F.

    2017-03-01

    We present a numerical study of quasiperiodic foams, in which the bubbles are generated as duals of quasiperiodic Frank–Kasper phases. These foams are investigated as potential candidates to the celebrated Kelvin problem for the partition of three-dimensional space with equal volume bubbles and minimal surface area. Interestingly, one of the computed structures falls close to (but still slightly above) the best known Weaire–Phelan periodic candidate. In addition we find a correlation between the normalized bubble surface area and the root mean squared deviation of the number of faces, giving an additional clue to understanding the main geometrical ingredients driving the Kelvin problem.

  11. Three-dimensional polarization algebra.

    PubMed

    R Sheppard, Colin J; Castello, Marco; Diaspro, Alberto

    2016-10-01

    If light is focused or collected with a high numerical aperture lens, as may occur in imaging and optical encryption applications, polarization should be considered in three dimensions (3D). The matrix algebra of polarization behavior in 3D is discussed. It is useful to convert between the Mueller matrix and two different Hermitian matrices, representing an optical material or system, which are in the literature. Explicit transformation matrices for converting the column vector form of these different matrices are extended to the 3D case, where they are large (81×81) but can be generated using simple rules. It is found that there is some advantage in using a generalization of the Chandrasekhar phase matrix treatment, rather than that based on Gell-Mann matrices, as the resultant matrices are of simpler form and reduce to the two-dimensional case more easily. Explicit expressions are given for 3D complex field components in terms of Chandrasekhar-Stokes parameters.

  12. Three-dimensional vortex methods

    SciTech Connect

    Greengard, C.A.

    1984-08-01

    Three-dimensional vortex methods for the computation of incompressible fluid flow are presented from a unified point of view. Reformulations of the filament method and of the method of Beale and Majda show them to be very similar algorithms; in both of them, the vorticity is evaluated by a discretization of the spatial derivative of the flow map. The fact that the filament method, the one which is most often used in practice, can be formulated as a version of the Beale and Majda algorithm in a curved coordinate system is used to give a convergence theorem for the filament method. The method of Anderson is also discussed, in which vorticity is evaluated by the exact differentiation of the approximate velocity field. It is shown that, in the inviscid version of this algorithm, each approximate vector of vorticity remains tangent to a material curve moving with the computed flow, with magnitude proportional to the stretching of this vortex line. This remains true even when time discretization is taken into account. It is explained that the expanding core vortex method converges to a system of equations different from the Navier-Stokes equations. Computations with the filament method of the inviscid interaction of two vortex rings are reported, both with single filaments in each ring and with a fully three-dimensional discretization of vorticity. The dependence on parameters is discussed, and convergence of the computed solutions is observed. 36 references, 4 figures.

  13. Ordered three-dimensional interconnected nanoarchitectures in anodic porous alumina

    PubMed Central

    Martín, Jaime; Martín-González, Marisol; Fernández, Jose Francisco; Caballero-Calero, Olga

    2014-01-01

    Three-dimensional nanostructures combine properties of nanoscale materials with the advantages of being macro-sized pieces when the time comes to manipulate, measure their properties, or make a device. However, the amount of compounds with the ability to self-organize in ordered three-dimensional nanostructures is limited. Therefore, template-based fabrication strategies become the key approach towards three-dimensional nanostructures. Here we report the simple fabrication of a template based on anodic aluminum oxide, having a well-defined, ordered, tunable, homogeneous 3D nanotubular network in the sub 100 nm range. The three-dimensional templates are then employed to achieve three-dimensional, ordered nanowire-networks in Bi2Te3 and polystyrene. Lastly, we demonstrate the photonic crystal behavior of both the template and the polystyrene three-dimensional nanostructure. Our approach may establish the foundations for future high-throughput, cheap, photonic materials and devices made of simple commodity plastics, metals, and semiconductors. PMID:25342247

  14. 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.

  15. Digital vision system for three-dimensional model acquisition

    NASA Astrophysics Data System (ADS)

    Yuan, Ta; Lin, Huei-Yung; Qin, Xiangdong; Subbarao, Murali

    2000-10-01

    A digital vision system and the computational algorithms used by the system for three-dimensional (3D) model acquisition are described. The system is named Stonybrook VIsion System (SVIS). The system can acquire the 3D model (which includes the 3D shape and the corresponding image texture) of a simple object within a 300 mm X 300 mm X 300 mm volume placed about 600 mm from the system. SVIS integrates Image Focus Analysis (IFA) and Stereo Image Analysis (SIA) techniques for 3D shape and image texture recovery. First, 4 to 8 partial 3D models of the object are obtained from 4 to 8 views of the object. The partial models are then integrated to obtain a complete model of the object. The complete model is displayed using a 3D graphics rendering software (Apple's QuickDraw). Experimental results on several objects are presented.

  16. Three-dimensional flow in the storative semiconfining layers of a leaky aquifer

    USGS Publications Warehouse

    Sepulveda, N.

    2008-01-01

    An analytical solution for three-dimensional (3D) flow in the storative semiconfining layers of a leaky aquifer fully penetrated by a production well is developed in this article to provide a method from which accurate hydraulic parameters in the semiconfining layers can be derived from aquifer test data. The analysis of synthetic aquifer test data with the 3D analytical solution in the semiconfining layers provided more accurate optimal hydraulic parameters than those derived using the available quasi-two-dimensional (2D) solution. Differences between the 3D and 2D flow solutions in the semiconfining layers become larger when a no flow boundary condition is imposed at either at the top of the upper semiconfining layer or at the bottom of the lower semiconfining layer or when the hydraulic conductivity ratio of the semiconfining layer to the aquifer is larger than 0.001. In addition, differences between the 3D and 2D flow solutions in the semiconfining layers are illustrated when the thickness ratio of the semiconfining layer to the aquifer is changed. Analysis of water level data from two hypothetical and one real aquifer test showed that the 3D solution in the semiconfining layers provides lower correlation coefficients among hydraulic parameters than the 2D solution. ?? 2007 National Ground Water Association.

  17. Medical three-dimensional printing opens up new opportunities in cardiology and cardiac surgery.

    PubMed

    Bartel, Thomas; Rivard, Andrew; Jimenez, Alejandro; Mestres, Carlos A; Müller, Silvana

    2017-02-16

    Advanced percutaneous and surgical procedures in structural and congenital heart disease require precise pre-procedural planning and continuous quality control. Although current imaging modalities and post-processing software assists with peri-procedural guidance, their capabilities for spatial conceptualization remain limited in two- and three-dimensional representations. In contrast, 3D printing offers not only improved visualization for procedural planning, but provides substantial information on the accuracy of surgical reconstruction and device implantations. Peri-procedural 3D printing has the potential to set standards of quality assurance and individualized healthcare in cardiovascular medicine and surgery. Nowadays, a variety of clinical applications are available showing how accurate 3D computer reformatting and physical 3D printouts of native anatomy, embedded pathology, and implants are and how they may assist in the development of innovative therapies. Accurate imaging of pathology including target region for intervention, its anatomic features and spatial relation to the surrounding structures is critical for selecting optimal approach and evaluation of procedural results. This review describes clinical applications of 3D printing, outlines current limitations, and highlights future implications for quality control, advanced medical education and training.

  18. Temporal speckle method for measuring three-dimensional surface of large-sized rough glass

    NASA Astrophysics Data System (ADS)

    Li, Chao; Zhou, Changhe; Wang, Shaoqing; Fan, Xin; Yang, Boquan; Lu, Yancong; Li, Hao; Liu, Zhao

    2016-10-01

    To provide accurate three-dimensional (3-D) data for production and processing, 3-D surface measurement is always an essential step to the production of glass. Profilometry and Interferometry are traditional measurement apparatus, referring to different procedures. Although more precise, Interferometry cannot be used in milling procedure, owing to the scattering property of rough glass. While as a widely used Profilometry, Coordinate Measuring Machine (CMM) employs a probe for measuring by contacting surface directly. It should be noted that such a time-consuming machine is not practical for measuring large-sized rough glass, so a novel designed method called temporal speckle is introduced to a non-contact binocular 3-D measurement system for measuring. Specifically, N band-limited binary patterns are sequentially projected to rough glass from a pattern generation device, such patterns have been proved to depress scattering properties of rough surface. The whole binocular 3-D measurement system can finish a single measurement in one second with a standard deviation less than 73.44um. This system performs fast and accurate 3-D surface measurement for large-sized rough glass block.

  19. Experiments with a three-dimensional statistical objective analysis scheme using FGGE data

    NASA Technical Reports Server (NTRS)

    Baker, Wayman E.; Bloom, Stephen C.; Woollen, John S.; Nestler, Mark S.; Brin, Eugenia

    1987-01-01

    A three-dimensional (3D), multivariate, statistical objective analysis scheme (referred to as optimum interpolation or OI) has been developed for use in numerical weather prediction studies with the FGGE data. Some novel aspects of the present scheme include: (1) a multivariate surface analysis over the oceans, which employs an Ekman balance instead of the usual geostrophic relationship, to model the pressure-wind error cross correlations, and (2) the capability to use an error correlation function which is geographically dependent. A series of 4-day data assimilation experiments are conducted to examine the importance of some of the key features of the OI in terms of their effects on forecast skill, as well as to compare the forecast skill using the OI with that utilizing a successive correction method (SCM) of analysis developed earlier. For the three cases examined, the forecast skill is found to be rather insensitive to varying the error correlation function geographically. However, significant differences are noted between forecasts from a two-dimensional (2D) version of the OI and those from the 3D OI, with the 3D OI forecasts exhibiting better forecast skill. The 3D OI forecasts are also more accurate than those from the SCM initial conditions. The 3D OI with the multivariate oceanic surface analysis was found to produce forecasts which were slightly more accurate, on the average, than a univariate version.

  20. A novel technique for three-dimensional reconstruction for surgical simulation around the craniocervical junction region.

    PubMed

    Liu, Guang-Jiu; Zhang, Shao-Xiang; Qiu, Ming-Guo; Tan, Li-Wen; Li, Qi-Yu; Li, Kai

    2011-01-01

    Performing surgeries on the craniocervical junction presents a technical challenge for operating surgeons. Three-dimensional (3D) reconstruction and surgical simulation have improved the efficacy and success rate of surgeries. The aim of this study was to create a 3D, digitized visible model of the craniocervical junction region to help realize accurate simulation of craniocervical surgery on a graphic workstation. Transverse sectional anatomy data for the study were chosen from the first Chinese visible human. Manual axial segmentation of the skull base, cervical spine, cerebellum, vertebral artery, internal carotid artery, sigmoid sinus, internal jugular vein, brain stem, and spinal cord were carried out by using Photoshop software. The segmented structures were reconstructed in 3 dimensions with surface and volume rendering to accurately display 3D models spatially. In contrast to conventional 3D reconstruction techniques that are based on computed tomography and magnetic resonance imaging Digital Imaging and Communications in Medicine (DICOM) inputs and provide mostly osseous details, this technique can help to illustrate the surrounding soft tissue structure and provide a realistic surgical simulation. The reconstructed 3D model was successfully used in simulating complex procedures in the virtual environment, including the transoral approach, bone drillings, and clivus resection.

  1. Three-Dimensional Surface Imaging is an Effective Tool for Measuring Breast Volume: A Validation Study

    PubMed Central

    Lee, Woo Yeon; Kim, Min Jung; Lew, Dae Hyun; Song, Seung Yong

    2016-01-01

    Background Accurate breast volume assessment is a prerequisite to preoperative planning, as well as intraoperative decision making in breast reconstruction surgery. The use of three-dimensional surface imaging (3D scanning) to assess breast volume has many advantages. However, before employing 3D scanning in the field, the tool's validity should be demonstrated. The purpose of this study was to confirm the validity of 3D-scanning technology for evaluating breast volume. Methods We reviewed the charts of 25 patients who underwent breast reconstruction surgery immediately after total mastectomy. Breast volumes using the Axis Three 3D scanner, water-displacement technique, and magnetic resonance imaging (MRI) were obtained bilaterally in the preoperative period. During the operation, the tissue removed during total mastectomy was weighed and the specimen volume was calculated from the weight. Then, we compared the volume obtained from 3D scanning with those obtained using the water-displacement technique, MRI, and the calculated volume of the tissue removed. Results The intraclass correlation coefficient (ICC) of breast volumes obtained from 3D scanning, as compared to the volumes obtained using the water-displacement technique and specimen weight, demonstrated excellent reliability. The ICC of breast volumes obtained using 3D scanning, as compared to those obtained by MRI, demonstrated substantial reliability. Passing-Bablok regression showed agreement between 3D scanning and the water-displacement technique, and showed a linear association of 3D scanning with MRI and specimen volume, respectively. Conclusions When compared with the classical water-displacement technique and MRI-based volumetry, 3D scanning showed significant reliability and a linear association with the other two methods. PMID:27689050

  2. High-resolution three-dimensional simulations of core-collapse supernovae in multiple progenitors

    SciTech Connect

    Couch, Sean M.; O'Connor, Evan P.

    2014-04-20

    Three-dimensional (3D) simulations of core-collapse supernovae (CCSNe) are granting new insight into the as-yet-uncertain mechanism that drives successful explosions. While there is still debate about whether explosions are obtained more easily in 3D than in 2D, it is undeniable that there exist qualitative and quantitative differences between the results of 3D and 2D simulations. We present an extensive set of high-resolution 1D, 2D, and 3D CCSN simulations with multispecies neutrino leakage carried out in two different progenitors. Our simulations confirm the results of Couch indicating that 2D explodes more readily than 3D. We argue that this is due to the inadequacies of 2D to accurately capture important aspects of the 3D dynamics. We find that without artificially enhancing the neutrino heating rate, we do not obtain explosions in 3D. We examine the development of neutrino-driven convection and the standing accretion shock instability (SASI) and find that, in separate regimes, either instability can dominate. We find evidence for growth of the SASI for both 15 M {sub ☉} and 27 M {sub ☉} progenitors; however, it is weaker in 3D exploding models. The growth rate of both instabilities is artificially enhanced along the symmetry axis in 2D as compared with our axis-free 3D Cartesian simulations. Our work highlights the growing consensus that CCSNe must be studied in 3D if we hope to solve the mystery of how the explosions are powered.

  3. Accurate and Fully Automatic Hippocampus Segmentation Using Subject-Specific 3D Optimal Local Maps Into a Hybrid Active Contour Model

    PubMed Central

    Gkontra, Polyxeni; Daras, Petros; Maglaveras, Nicos

    2014-01-01

    Assessing the structural integrity of the hippocampus (HC) is an essential step toward prevention, diagnosis, and follow-up of various brain disorders due to the implication of the structural changes of the HC in those disorders. In this respect, the development of automatic segmentation methods that can accurately, reliably, and reproducibly segment the HC has attracted considerable attention over the past decades. This paper presents an innovative 3-D fully automatic method to be used on top of the multiatlas concept for the HC segmentation. The method is based on a subject-specific set of 3-D optimal local maps (OLMs) that locally control the influence of each energy term of a hybrid active contour model (ACM). The complete set of the OLMs for a set of training images is defined simultaneously via an optimization scheme. At the same time, the optimal ACM parameters are also calculated. Therefore, heuristic parameter fine-tuning is not required. Training OLMs are subsequently combined, by applying an extended multiatlas concept, to produce the OLMs that are anatomically more suitable to the test image. The proposed algorithm was tested on three different and publicly available data sets. Its accuracy was compared with that of state-of-the-art methods demonstrating the efficacy and robustness of the proposed method. PMID:27170866

  4. Three dimensional audio versus head down TCAS displays

    NASA Technical Reports Server (NTRS)

    Begault, Durand R.; Pittman, Marc T.

    1994-01-01

    The advantage of a head up auditory display was evaluated in an experiment designed to measure and compare the acquisition time for capturing visual targets under two conditions: Standard head down traffic collision avoidance system (TCAS) display, and three-dimensional (3-D) audio TCAS presentation. Ten commercial airline crews were tested under full mission simulation conditions at the NASA Ames Crew-Vehicle Systems Research Facility Advanced Concepts Flight Simulator. Scenario software generated targets corresponding to aircraft which activated a 3-D aural advisory or a TCAS advisory. Results showed a significant difference in target acquisition time between the two conditions, favoring the 3-D audio TCAS condition by 500 ms.

  5. Three-dimensional aerodynamic shape optimization of supersonic delta wings

    NASA Technical Reports Server (NTRS)

    Burgreen, Greg W.; Baysal, Oktay

    1994-01-01

    A recently developed three-dimensional aerodynamic shape optimization procedure AeSOP(sub 3D) is described. This procedure incorporates some of the most promising concepts from the area of computational aerodynamic analysis and design, specifically, discrete sensitivity analysis, a fully implicit 3D Computational Fluid Dynamics (CFD) methodology, and 3D Bezier-Bernstein surface parameterizations. The new procedure is demonstrated in the preliminary design of supersonic delta wings. Starting from a symmetric clipped delta wing geometry, a Mach 1.62 asymmetric delta wing and two Mach 1. 5 cranked delta wings were designed subject to various aerodynamic and geometric constraints.

  6. The optical Anderson localization in three-dimensional percolation system

    NASA Astrophysics Data System (ADS)

    Burlak, G.; Martinez-Sánchez, E.

    2017-03-01

    We study the optical Anderson localization associated with the properties of three-dimensional (3D) disordered percolation system, where the percolating clusters are filled by active media composed by light noncoherent emitters. In such a non-uniformly spatial structure the radiating and scattering of field occur by incoherent way. We numerically study 3D field structures where the wave localization takes place and propose the criterion of field localization based on conception of a mean photon free path in such system. The analysis of a mean free path and the Inverse participation ratio (IPR) shows that the localization arises closely to the threshold of 3D percolation phase transition.

  7. Three-dimensional assessment of facial asymmetry: A systematic review

    PubMed Central

    Akhil, Gopi; Senthil Kumar, Kullampalayam Palanisamy; Raja, Subramani; Janardhanan, Kumaresan

    2015-01-01

    For patients with facial asymmetry, complete and precise diagnosis, and surgical treatments to correct the underlying cause of the asymmetry are significant. Conventional diagnostic radiographs (submento-vertex projections, posteroanterior radiography) have limitations in asymmetry diagnosis due to two-dimensional assessments of three-dimensional (3D) images. The advent of 3D images has greatly reduced the magnification and projection errors that are common in conventional radiographs making it as a precise diagnostic aid for assessment of facial asymmetry. Thus, this article attempts to review the newly introduced 3D tools in the diagnosis of more complex facial asymmetries. PMID:26538893

  8. Displaying three-dimensional medical objects by holographical technique

    NASA Astrophysics Data System (ADS)

    Teng, Dongdong; Pang, Zhiyong; Liu, Lilin; Wang, Biao

    2014-11-01

    A three-dimensional (3-D) display system for medical objects by holographic technique has been developed. A shiftable cylindrical lens is introduced to refract the 3-D images projected from the spatial light modulator. The viewing region of the refracted image changes with the position of the cylindrical lens. Through an imaging lens, the refracted images with different viewing regions are imaged into the same target object and a 3-D medical display with an enlarged viewing angle is implemented based on time-multiplexing method. The displayed object can be viewed within 17 deg at the front of the display.

  9. THREE-DIMENSIONAL WAVY HELIOSPHERIC CURRENT SHEET DRIFTS

    SciTech Connect

    Pei, C.; Bieber, J. W.; Clem, J.; Burger, R. A.

    2012-01-10

    We present an analytic method to determine the directions of the three-dimensional (3D) heliospheric current sheet (HCS) drift for any tilt angle based on Parker's heliospheric magnetic field and compare it with published two-dimensional and quasi-3D methods. We also present a new approach to determine the magnitude of the 3D HCS drift numerically. Implications of these new methods for the solar modulation of Galactic cosmic rays are considered and compared with results from prior methods reported in the literature. Our results support the concept that HCS drift plays an important role in the solar modulation of cosmic rays.

  10. Can we get 3D-CD metrology right?

    NASA Astrophysics Data System (ADS)

    Vladár, András E.; Cizmar, Petr; Villarrubia, John S.; Postek, Michael T.

    2012-03-01

    Our world is three-dimensional, and so are the integrated circuits (ICs), they have always been. In the past, for a long time, we have been very fortunate, because it was enough to measure a simple critical dimension (CD), the width of the resist line, to keep IC production under acceptable control. This requirement has changed in the last few years to contour and now to three-dimensional measurements. Optical lithography is printing photoresist features that are significantly smaller than the wavelength of the light used, and therefore it is indispensable to use optical proximity correction (OPC) methods. This includes modeling and compensation for various errors in the lithography process down to sub-nanometer, essentially atomic levels. The process has to rely on sophisticated and complex simulations and on accurate and highly repeatable dimensional metrology. The necessary dimensional metrology is beyond the conventional one-dimensional line width measurements, and must include two - and three-dimensional measurements of the contours and shapes of structures. Contour metrology needs accurate and highly repeatable measurements on sets and individual OPC structures, for which the critical dimension measurement scanning electron microscope (CD-SEM) is the key metrology tool. Three-dimensional (3D) metrology is now indispensable for IC technology, but current metrology tools and methods cannot fulfill the requirements. We believe that with the implementation of new methods it is feasible to develop 3D metrology that will well serve IC production, even on structures in the few nanometer-size range.

  11. MR diffusion-weighted imaging-based subcutaneous tumour volumetry in a xenografted nude mouse model using 3D Slicer: an accurate and repeatable method

    PubMed Central

    Ma, Zelan; Chen, Xin; Huang, Yanqi; He, Lan; Liang, Cuishan; Liang, Changhong; Liu, Zaiyi

    2015-01-01

    Accurate and repeatable measurement of the gross tumour volume(GTV) of subcutaneous xenografts is crucial in the evaluation of anti-tumour therapy. Formula and image-based manual segmentation methods are commonly used for GTV measurement but are hindered by low accuracy and reproducibility. 3D Slicer is open-source software that provides semiautomatic segmentation for GTV measurements. In our study, subcutaneous GTVs from nude mo