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Sample records for 3d constrained triangulation

  1. Hex-dominant mesh generation using 3D constrained triangulation

    SciTech Connect

    OWEN,STEVEN J.

    2000-05-30

    A method for decomposing a volume with a prescribed quadrilateral surface mesh, into a hexahedral-dominated mesh is proposed. With this method, known as Hex-Morphing (H-Morph), an initial tetrahedral mesh is provided. Tetrahedral are transformed and combined starting from the boundary and working towards the interior of the volume. The quadrilateral faces of the hexahedra are treated as internal surfaces, which can be recovered using constrained triangulation techniques. Implementation details of the edge and face recovery process are included. Examples and performance of the H-Morph algorithm are also presented.

  2. 3D Laser Triangulation for Plant Phenotyping in Challenging Environments

    PubMed Central

    Kjaer, Katrine Heinsvig; Ottosen, Carl-Otto

    2015-01-01

    To increase the understanding of how the plant phenotype is formed by genotype and environmental interactions, simple and robust high-throughput plant phenotyping methods should be developed and considered. This would not only broaden the application range of phenotyping in the plant research community, but also increase the ability for researchers to study plants in their natural environments. By studying plants in their natural environment in high temporal resolution, more knowledge on how multiple stresses interact in defining the plant phenotype could lead to a better understanding of the interaction between plant responses and epigenetic regulation. In the present paper, we evaluate a commercial 3D NIR-laser scanner (PlantEye, Phenospex B.V., Herleen, The Netherlands) to track daily changes in plant growth with high precision in challenging environments. Firstly, we demonstrate that the NIR laser beam of the scanner does not affect plant photosynthetic performance. Secondly, we demonstrate that it is possible to estimate phenotypic variation amongst the growth pattern of ten genotypes of Brassica napus L. (rapeseed), using a simple linear correlation between scanned parameters and destructive growth measurements. Our results demonstrate the high potential of 3D laser triangulation for simple measurements of phenotypic variation in challenging environments and in a high temporal resolution. PMID:26066990

  3. Triangulation Based 3D Laser Imaging for Fracture Orientation Analysis

    NASA Astrophysics Data System (ADS)

    Mah, J.; Claire, S.; Steve, M.

    2009-05-01

    Laser imaging has recently been identified as a potential tool for rock mass characterization. This contribution focuses on the application of triangulation based, short-range laser imaging to determine fracture orientation and surface texture. This technology measures the distance to the target by triangulating the projected and reflected laser beams, and also records the reflection intensity. In this study, we acquired 3D laser images of rock faces using the Laser Camera System (LCS), a portable instrument developed by Neptec Design Group (Ottawa, Canada). The LCS uses an infrared laser beam and is immune to the lighting conditions. The maximum image resolution is 1024 x 1024 volumetric image elements. Depth resolution is 0.5 mm at 5 m. An above ground field trial was conducted at a blocky road cut with well defined joint sets (Kingston, Ontario). An underground field trial was conducted at the Inco 175 Ore body (Sudbury, Ontario) where images were acquired in the dark and the joint set features were more subtle. At each site, from a distance of 3 m away from the rock face, a grid of six images (approximately 1.6 m by 1.6 m) was acquired at maximum resolution with 20% overlap between adjacent images. This corresponds to a density of 40 image elements per square centimeter. Polyworks, a high density 3D visualization software tool, was used to align and merge the images into a single digital triangular mesh. The conventional method of determining fracture orientations is by manual measurement using a compass. In order to be accepted as a substitute for this method, the LCS should be capable of performing at least to the capabilities of manual measurements. To compare fracture orientation estimates derived from the 3D laser images to manual measurements, 160 inclinometer readings were taken at the above ground site. Three prominent joint sets (strike/dip: 236/09, 321/89, 325/01) were identified by plotting the joint poles on a stereonet. Underground, two main joint

  4. Onomatopoeia characters extraction from comic images using constrained Delaunay triangulation

    NASA Astrophysics Data System (ADS)

    Liu, Xiangping; Shoji, Kenji; Mori, Hiroshi; Toyama, Fubito

    2014-02-01

    A method for extracting onomatopoeia characters from comic images was developed based on stroke width feature of characters, since they nearly have a constant stroke width in a number of cases. An image was segmented with a constrained Delaunay triangulation. Connected component grouping was performed based on the triangles generated by the constrained Delaunay triangulation. Stroke width calculation of the connected components was conducted based on the altitude of the triangles generated with the constrained Delaunay triangulation. The experimental results proved the effectiveness of the proposed method.

  5. Calibration Methods for a 3D Triangulation Based Camera

    NASA Astrophysics Data System (ADS)

    Schulz, Ulrike; Böhnke, Kay

    A sensor in a camera takes a gray level image (1536 x 512 pixels), which is reflected by a reference body. The reference body is illuminated by a linear laser line. This gray level image can be used for a 3D calibration. The following paper describes how a calibration program calculates the calibration factors. The calibration factors serve to determine the size of an unknown reference body.

  6. Computing 2D constrained delaunay triangulation using the GPU.

    PubMed

    Qi, Meng; Cao, Thanh-Tung; Tan, Tiow-Seng

    2013-05-01

    We propose the first graphics processing unit (GPU) solution to compute the 2D constrained Delaunay triangulation (CDT) of a planar straight line graph (PSLG) consisting of points and edges. There are many existing CPU algorithms to solve the CDT problem in computational geometry, yet there has been no prior approach to solve this problem efficiently using the parallel computing power of the GPU. For the special case of the CDT problem where the PSLG consists of just points, which is simply the normal Delaunay triangulation (DT) problem, a hybrid approach using the GPU together with the CPU to partially speed up the computation has already been presented in the literature. Our work, on the other hand, accelerates the entire computation on the GPU. Our implementation using the CUDA programming model on NVIDIA GPUs is numerically robust, and runs up to an order of magnitude faster than the best sequential implementations on the CPU. This result is reflected in our experiment with both randomly generated PSLGs and real-world GIS data having millions of points and edges. PMID:23492377

  7. Performance Analysis of a Low-Cost Triangulation-Based 3d Camera: Microsoft Kinect System

    NASA Astrophysics Data System (ADS)

    . K. Chow, J. C.; Ang, K. D.; Lichti, D. D.; Teskey, W. F.

    2012-07-01

    Recent technological advancements have made active imaging sensors popular for 3D modelling and motion tracking. The 3D coordinates of signalised targets are traditionally estimated by matching conjugate points in overlapping images. Current 3D cameras can acquire point clouds at video frame rates from a single exposure station. In the area of 3D cameras, Microsoft and PrimeSense have collaborated and developed an active 3D camera based on the triangulation principle, known as the Kinect system. This off-the-shelf system costs less than 150 USD and has drawn a lot of attention from the robotics, computer vision, and photogrammetry disciplines. In this paper, the prospect of using the Kinect system for precise engineering applications was evaluated. The geometric quality of the Kinect system as a function of the scene (i.e. variation of depth, ambient light conditions, incidence angle, and object reflectivity) and the sensor (i.e. warm-up time and distance averaging) were analysed quantitatively. This system's potential in human body measurements was tested against a laser scanner and 3D range camera. A new calibration model for simultaneously determining the exterior orientation parameters, interior orientation parameters, boresight angles, leverarm, and object space features parameters was developed and the effectiveness of this calibration approach was explored.

  8. Spectral triangulation: a 3D method for locating single-walled carbon nanotubes in vivo.

    PubMed

    Lin, Ching-Wei; Bachilo, Sergei M; Vu, Michael; Beckingham, Kathleen M; Bruce Weisman, R

    2016-05-21

    Nanomaterials with luminescence in the short-wave infrared (SWIR) region are of special interest for biological research and medical diagnostics because of favorable tissue transparency and low autofluorescence backgrounds in that region. Single-walled carbon nanotubes (SWCNTs) show well-known sharp SWIR spectral signatures and therefore have potential for noninvasive detection and imaging of cancer tumours, when linked to selective targeting agents such as antibodies. However, such applications face the challenge of sensitively detecting and localizing the source of SWIR emission from inside tissues. A new method, called spectral triangulation, is presented for three dimensional (3D) localization using sparse optical measurements made at the specimen surface. Structurally unsorted SWCNT samples emitting over a range of wavelengths are excited inside tissue phantoms by an LED matrix. The resulting SWIR emission is sampled at points on the surface by a scanning fibre optic probe leading to an InGaAs spectrometer or a spectrally filtered InGaAs avalanche photodiode detector. Because of water absorption, attenuation of the SWCNT fluorescence in tissues is strongly wavelength-dependent. We therefore gauge the SWCNT-probe distance by analysing differential changes in the measured SWCNT emission spectra. SWCNT fluorescence can be clearly detected through at least 20 mm of tissue phantom, and the 3D locations of embedded SWCNT test samples are found with sub-millimeter accuracy at depths up to 10 mm. Our method can also distinguish and locate two embedded SWCNT sources at distinct positions. PMID:27140495

  9. Spectral triangulation: a 3D method for locating single-walled carbon nanotubes in vivo

    NASA Astrophysics Data System (ADS)

    Lin, Ching-Wei; Bachilo, Sergei M.; Vu, Michael; Beckingham, Kathleen M.; Bruce Weisman, R.

    2016-05-01

    Nanomaterials with luminescence in the short-wave infrared (SWIR) region are of special interest for biological research and medical diagnostics because of favorable tissue transparency and low autofluorescence backgrounds in that region. Single-walled carbon nanotubes (SWCNTs) show well-known sharp SWIR spectral signatures and therefore have potential for noninvasive detection and imaging of cancer tumours, when linked to selective targeting agents such as antibodies. However, such applications face the challenge of sensitively detecting and localizing the source of SWIR emission from inside tissues. A new method, called spectral triangulation, is presented for three dimensional (3D) localization using sparse optical measurements made at the specimen surface. Structurally unsorted SWCNT samples emitting over a range of wavelengths are excited inside tissue phantoms by an LED matrix. The resulting SWIR emission is sampled at points on the surface by a scanning fibre optic probe leading to an InGaAs spectrometer or a spectrally filtered InGaAs avalanche photodiode detector. Because of water absorption, attenuation of the SWCNT fluorescence in tissues is strongly wavelength-dependent. We therefore gauge the SWCNT-probe distance by analysing differential changes in the measured SWCNT emission spectra. SWCNT fluorescence can be clearly detected through at least 20 mm of tissue phantom, and the 3D locations of embedded SWCNT test samples are found with sub-millimeter accuracy at depths up to 10 mm. Our method can also distinguish and locate two embedded SWCNT sources at distinct positions.Nanomaterials with luminescence in the short-wave infrared (SWIR) region are of special interest for biological research and medical diagnostics because of favorable tissue transparency and low autofluorescence backgrounds in that region. Single-walled carbon nanotubes (SWCNTs) show well-known sharp SWIR spectral signatures and therefore have potential for noninvasive detection and

  10. Bound constrained bundle adjustment for reliable 3D reconstruction.

    PubMed

    Gong, Yuanzheng; Meng, De; Seibel, Eric J

    2015-04-20

    Bundle adjustment (BA) is a common estimation algorithm that is widely used in machine vision as the last step in a feature-based three-dimensional (3D) reconstruction algorithm. BA is essentially a non-convex non-linear least-square problem that can simultaneously solve the 3D coordinates of all the feature points describing the scene geometry, as well as the parameters of the camera. The conventional BA takes a parameter either as a fixed value or as an unconstrained variable based on whether the parameter is known or not. In cases where the known parameters are inaccurate but constrained in a range, conventional BA results in an incorrect 3D reconstruction by using these parameters as fixed values. On the other hand, these inaccurate parameters can be treated as unknown variables, but this does not exploit the knowledge of the constraints, and the resulting reconstruction can be erroneous since the BA optimization halts at a dramatically incorrect local minimum due to its non-convexity. In many practical 3D reconstruction applications, unknown variables with range constraints are usually available, such as a measurement with a range of uncertainty or a bounded estimate. Thus to better utilize these pre-known, constrained, but inaccurate parameters, a bound constrained bundle adjustment (BCBA) algorithm is proposed, developed and tested in this study. A scanning fiber endoscope (the camera) is used to capture a sequence of images above a surgery phantom (the object) of known geometry. 3D virtual models are reconstructed based on these images and then compared with the ground truth. The experimental results demonstrate BCBA can achieve a more reliable, rapid, and accurate 3D reconstruction than conventional bundle adjustment. PMID:25969115

  11. Bound constrained bundle adjustment for reliable 3D reconstruction

    PubMed Central

    Gong, Yuanzheng; Meng, De; Seibel, Eric J.

    2015-01-01

    Bundle adjustment (BA) is a common estimation algorithm that is widely used in machine vision as the last step in a feature-based three-dimensional (3D) reconstruction algorithm. BA is essentially a non-convex non-linear least-square problem that can simultaneously solve the 3D coordinates of all the feature points describing the scene geometry, as well as the parameters of the camera. The conventional BA takes a parameter either as a fixed value or as an unconstrained variable based on whether the parameter is known or not. In cases where the known parameters are inaccurate but constrained in a range, conventional BA results in an incorrect 3D reconstruction by using these parameters as fixed values. On the other hand, these inaccurate parameters can be treated as unknown variables, but this does not exploit the knowledge of the constraints, and the resulting reconstruction can be erroneous since the BA optimization halts at a dramatically incorrect local minimum due to its non-convexity. In many practical 3D reconstruction applications, unknown variables with range constraints are usually available, such as a measurement with a range of uncertainty or a bounded estimate. Thus to better utilize these pre-known, constrained, but inaccurate parameters, a bound constrained bundle adjustment (BCBA) algorithm is proposed, developed and tested in this study. A scanning fiber endoscope (the camera) is used to capture a sequence of images above a surgery phantom (the object) of known geometry. 3D virtual models are reconstructed based on these images and then compared with the ground truth. The experimental results demonstrate BCBA can achieve a more reliable, rapid, and accurate 3D reconstruction than conventional bundle adjustment. PMID:25969115

  12. Improved EEG source localization employing 3D sensing by "Flying Triangulation"

    NASA Astrophysics Data System (ADS)

    Ettl, Svenja; Rampp, Stefan; Fouladi-Movahed, Sarah; Dalal, Sarang S.; Willomitzer, Florian; Arold, Oliver; Stefan, Hermann; Häusler, Gerd

    2013-04-01

    With electroencephalography (EEG), a person's brain activity can be monitored over time and sources of activity localized. With this information, brain regions showing pathological activity, such as epileptic spikes, can be delineated. In cases of severe drug-resistant epilepsy, surgical resection of these brain regions may be the only treatment option. This requires a precise localization of the responsible seizure generators. They can be reconstructed from EEG data when the electrode positions are known. The standard method employs a "digitization pen" and has severe drawbacks: It is time consuming, the result is user-dependent, and the patient has to hold still. We present a novel method which overcomes these drawbacks. It is based on the optical "Flying Triangulation" (FlyTri) sensor which allows a motion-robust acquisition of precise 3D data. To compare the two methods, the electrode positions were determined with each method for a real-sized head model with EEG electrodes and their deviation to the ground-truth data calculated. The standard deviation for the current method was 3.39 mm while it was 0.98 mm for the new method. The influence of these results on the final EEG source localization was investigated by simulating EEG data. The digitization pen result deviates substantially from the true source location and time series. In contrast, the FlyTri result agrees with the original information. Our findings suggest that FlyTri might become a valuable tool in the field of medical brain research, because of its improved precision and contactless handling. Future applications might include co-registration of multimodal information.

  13. Flying triangulation - A motion-robust optical 3D sensor for the real-time shape acquisition of complex objects

    NASA Astrophysics Data System (ADS)

    Willomitzer, Florian; Ettl, Svenja; Arold, Oliver; Häusler, Gerd

    2013-05-01

    The three-dimensional shape acquisition of objects has become more and more important in the last years. Up to now, there are several well-established methods which already yield impressive results. However, even under quite common conditions like object movement or a complex shaping, most methods become unsatisfying. Thus, the 3D shape acquisition is still a difficult and non-trivial task. We present our measurement principle "Flying Triangulation" which enables a motion-robust 3D acquisition of complex-shaped object surfaces by a freely movable handheld sensor. Since "Flying Triangulation" is scalable, a whole sensor-zoo for different object sizes is presented. Concluding, an overview of current and future fields of investigation is given.

  14. Reconstruction, Quantification, and Visualization of Forest Canopy Based on 3d Triangulations of Airborne Laser Scanning Point Data

    NASA Astrophysics Data System (ADS)

    Vauhkonen, J.

    2015-03-01

    Reconstruction of three-dimensional (3D) forest canopy is described and quantified using airborne laser scanning (ALS) data with densities of 0.6-0.8 points m-2 and field measurements aggregated at resolutions of 400-900 m2. The reconstruction was based on computational geometry, topological connectivity, and numerical optimization. More precisely, triangulations and their filtrations, i.e. ordered sets of simplices belonging to the triangulations, based on the point data were analyzed. Triangulating the ALS point data corresponds to subdividing the underlying space of the points into weighted simplicial complexes with weights quantifying the (empty) space delimited by the points. Reconstructing the canopy volume populated by biomass will thus likely require filtering to exclude that volume from canopy voids. The approaches applied for this purpose were (i) to optimize the degree of filtration with respect to the field measurements, and (ii) to predict this degree by means of analyzing the persistent homology of the obtained triangulations, which is applied for the first time for vegetation point clouds. When derived from optimized filtrations, the total tetrahedral volume had a high degree of determination (R2) with the stem volume considered, both alone (R2=0.65) and together with other predictors (R2=0.78). When derived by analyzing the topological persistence of the point data and without any field input, the R2 were lower, but the predictions still showed a correlation with the field-measured stem volumes. Finally, producing realistic visualizations of a forested landscape using the persistent homology approach is demonstrated.

  15. 3D constrained inversion of geophysical and geological information applying Spatial Mutually Constrained Inversion.

    NASA Astrophysics Data System (ADS)

    Nielsen, O. F.; Ploug, C.; Mendoza, J. A.; Martínez, K.

    2009-05-01

    The need for increaseding accuracy and reduced ambiguities in the inversion results has resulted in focus on the development of more advanced inversion methods of geophysical data. Over the past few years more advanced inversion techniques have been developed to improve the results. Real 3D-inversion is time consuming and therefore often not the best solution in a cost-efficient perspective. This has motivated the development of 3D constrained inversions, where 1D-models are constrained in 3D, also known as a Spatial Constrained Inversion (SCI). Moreover, inversion of several different data types in one inversion has been developed, known as Mutually Constrained Inversion (MCI). In this paper a presentation of a Spatial Mutually Constrained Inversion method (SMCI) is given. This method allows 1D-inversion applied to different geophysical datasets and geological information constrained in 3D. Application of two or more types of geophysical methods in the inversion has proved to reduce the equivalence problem and to increase the resolution in the inversion results. The use of geological information from borehole data or digital geological models can be integrated in the inversion. In the SMCI, a 1D inversion code is used to model soundings that are constrained in three dimensions according to their relative position in space. This solution enhances the accuracy of the inversion and produces distinct layers thicknesses and resistivities. It is very efficient in the mapping of a layered geology but still also capable of mapping layer discontinuities that are, in many cases, related to fracturing and faulting or due to valley fills. Geological information may be included in the inversion directly or used only to form a starting model for the individual soundings in the inversion. In order to show the effectiveness of the method, examples are presented from both synthetic data and real data. The examples include DC-soundings as well as land-based and airborne TEM

  16. 3D polygonal representation of dense point clouds by triangulation, segmentation, and texture projection

    NASA Astrophysics Data System (ADS)

    Tajbakhsh, Touraj

    2010-02-01

    A basic concern of computer graphic is the modeling and realistic representation of three-dimensional objects. In this paper we present our reconstruction framework which determines a polygonal surface from a set of dense points such those typically obtained from laser scanners. We deploy the concept of adaptive blobs to achieve a first volumetric representation of the object. In the next step we estimate a coarse surface using the marching cubes method. We propose to deploy a depth-first search segmentation algorithm traversing a graph representation of the obtained polygonal mesh in order to identify all connected components. A so called supervised triangulation maps the coarse surfaces onto the dense point cloud. We optimize the mesh topology using edge exchange operations. For photo-realistic visualization of objects we finally synthesize optimal low-loss textures from available scene captures of different projections. We evaluate our framework on artificial data as well as real sensed data.

  17. 3D geometrical inspection of complex geometry parts using a novel laser triangulation sensor and a robot.

    PubMed

    Brosed, Francisco Javier; Aguilar, Juan José; Guillomía, David; Santolaria, Jorge

    2011-01-01

    This article discusses different non contact 3D measuring strategies and presents a model for measuring complex geometry parts, manipulated through a robot arm, using a novel vision system consisting of a laser triangulation sensor and a motorized linear stage. First, the geometric model incorporating an automatic simple module for long term stability improvement will be outlined in the article. The new method used in the automatic module allows the sensor set up, including the motorized linear stage, for the scanning avoiding external measurement devices. In the measurement model the robot is just a positioning of parts with high repeatability. Its position and orientation data are not used for the measurement and therefore it is not directly "coupled" as an active component in the model. The function of the robot is to present the various surfaces of the workpiece along the measurement range of the vision system, which is responsible for the measurement. Thus, the whole system is not affected by the robot own errors following a trajectory, except those due to the lack of static repeatability. For the indirect link between the vision system and the robot, the original model developed needs only one first piece measuring as a "zero" or master piece, known by its accurate measurement using, for example, a Coordinate Measurement Machine. The strategy proposed presents a different approach to traditional laser triangulation systems on board the robot in order to improve the measurement accuracy, and several important cues for self-recalibration are explored using only a master piece. Experimental results are also presented to demonstrate the technique and the final 3D measurement accuracy. PMID:22346569

  18. 3D Geometrical Inspection of Complex Geometry Parts Using a Novel Laser Triangulation Sensor and a Robot

    PubMed Central

    Brosed, Francisco Javier; Aguilar, Juan José; Guillomía, David; Santolaria, Jorge

    2011-01-01

    This article discusses different non contact 3D measuring strategies and presents a model for measuring complex geometry parts, manipulated through a robot arm, using a novel vision system consisting of a laser triangulation sensor and a motorized linear stage. First, the geometric model incorporating an automatic simple module for long term stability improvement will be outlined in the article. The new method used in the automatic module allows the sensor set up, including the motorized linear stage, for the scanning avoiding external measurement devices. In the measurement model the robot is just a positioning of parts with high repeatability. Its position and orientation data are not used for the measurement and therefore it is not directly “coupled” as an active component in the model. The function of the robot is to present the various surfaces of the workpiece along the measurement range of the vision system, which is responsible for the measurement. Thus, the whole system is not affected by the robot own errors following a trajectory, except those due to the lack of static repeatability. For the indirect link between the vision system and the robot, the original model developed needs only one first piece measuring as a “zero” or master piece, known by its accurate measurement using, for example, a Coordinate Measurement Machine. The strategy proposed presents a different approach to traditional laser triangulation systems on board the robot in order to improve the measurement accuracy, and several important cues for self-recalibration are explored using only a master piece. Experimental results are also presented to demonstrate the technique and the final 3D measurement accuracy. PMID:22346569

  19. Geometry of structures within crystalline bedrock constrained in 3D and their relevance for present day water infiltration.

    NASA Astrophysics Data System (ADS)

    Schneeberger, Raphael; de la Varga, Miguel; Florian Wellmann, J.; Kober, Florian; Berger, Alfons; Herwegh, Marco

    2016-04-01

    Fluid circulation in crystalline rocks is of key importance when exploring crystalline basement in light of, for example, deep-seated geothermal energy projects or selection of sites for nuclear waste repositories. Due to their enhanced permeability, fluid circulation within crystalline bedrock is mainly controlled by fault zones, which may originate from ductile mylonites but show a strong brittle overprint. In order to better constrain 3D flow paths, a well-founded knowledge on the 3D nature of the fault zone pattern is indispensable. We attempt to constrain the geometry of a complex 3D fault zone pattern in a case study of the Grimsel Test Site (GTS, central Switzerland). The constraints are based on mapping of both the surface as well as the GTS underground tunnel system, offering a unique opportunity to test the 3D model and associated uncertainties. We investigate the effect of increasing geoinformation on the quality and accuracy of the 3D model by using: (i) remote sensing surface data only, (ii) field surface mapping in combination with (i), and (iii) underground data combined with (i) and (ii). This approach allows for defining different steps in 3D geological modelling of a specific area, including a measure of the remaining uncertainty after each step. We obtain a best-estimate model by fitting results between surface and underground data by using a combination of field data and orientation obtained by Delaunay triangulation. We incorporate novel approaches to uncertainty analysis of fault orientations and investigate different fault planes showing the possible variation range of the structures investigated.

  20. 2D inverse modeling for potential fields on rugged observation surface using constrained Delaunay triangulation

    NASA Astrophysics Data System (ADS)

    Liu, Shuang; Hu, Xiangyun; Xi, Yufei; Liu, Tianyou

    2015-03-01

    The regular grid discretization is prevalent in the inverse modeling for gravity and magnetic data. However, this subdivision strategy performs lower precision to represent the rugged observation surface. To deal with this problem, we evaluate a non-structured discretization method in which the subsurface with rolling terrain is divided into numbers of Delaunay triangular cells and each mesh has the uniform physical property distributions. The gravity and magnetic anomalies of a complex-shaped anomalous body are represented as the summaries of the single anomaly produced by each triangle field source. When inverting for the potential field data, we specify a minimization objective function composed of data constraints and then use the preconditioned conjugate gradient algorithm to iteratively solve the matrix minimization equations, where the preconditioner is determined by the distances between triangular cells and surface observers. We test our method using synthetic data; all tests return favorable results. In the case studies involving the gravity and magnetic anomalies of the Mengku and Pobei deposits in Xinjiang, northwest China, the inferred magnetite orebodies and ultrabasic rocks distributions are verified by the additional drilling and geological information. The discretization of constrained Delaunay triangulation provides an useful approach of computing and inverting the potential field data on the situations of undulate topography and complicated objects.

  1. Necking and failure of constrained 3D microtissues induced by cellular tension

    PubMed Central

    Wang, Hailong; Svoronos, Alexander A.; Boudou, Thomas; Sakar, Mahmut Selman; Schell, Jacquelyn Youssef; Morgan, Jeffrey R.; Chen, Christopher S.; Shenoy, Vivek B.

    2013-01-01

    In this paper we report a fundamental morphological instability of constrained 3D microtissues induced by positive chemomechanical feedback between actomyosin-driven contraction and the mechanical stresses arising from the constraints. Using a 3D model for mechanotransduction we find that perturbations in the shape of contractile tissues grow in an unstable manner leading to formation of “necks” that lead to the failure of the tissue by narrowing and subsequent elongation. The magnitude of the instability is shown to be determined by the level of active contractile strain, the stiffness of the extracellular matrix, and the components of the tissue that act in parallel with the active component and the stiffness of the boundaries that constrain the tissue. A phase diagram that demarcates stable and unstable behavior of 3D tissues as a function of these material parameters is derived. The predictions of our model are verified by analyzing the necking and failure of normal human fibroblast tissue constrained in a loop-ended dog-bone geometry and cardiac microtissues constrained between microcantilevers. By analyzing the time evolution of the morphology of the constrained tissues we have quantitatively determined the chemomechanical coupling parameters that characterize the generation of active stresses in these tissues. More generally, the analytical and numerical methods we have developed provide a quantitative framework to study how contractility can influence tissue morphology in complex 3D environments such as morphogenesis and organogenesis. PMID:24324149

  2. Rate-constrained 3D surface estimation from noise-corrupted multiview depth videos.

    PubMed

    Sun, Wenxiu; Cheung, Gene; Chou, Philip A; Florencio, Dinei; Zhang, Cha; Au, Oscar C

    2014-07-01

    Transmitting compactly represented geometry of a dynamic 3D scene from a sender can enable a multitude of imaging functionalities at a receiver, such as synthesis of virtual images at freely chosen viewpoints via depth-image-based rendering. While depth maps—projections of 3D geometry onto 2D image planes at chosen camera viewpoints-can nowadays be readily captured by inexpensive depth sensors, they are often corrupted by non-negligible acquisition noise. Given depth maps need to be denoised and compressed at the encoder for efficient network transmission to the decoder, in this paper, we consider the denoising and compression problems jointly, arguing that doing so will result in a better overall performance than the alternative of solving the two problems separately in two stages. Specifically, we formulate a rate-constrained estimation problem, where given a set of observed noise-corrupted depth maps, the most probable (maximum a posteriori (MAP)) 3D surface is sought within a search space of surfaces with representation size no larger than a prespecified rate constraint. Our rate-constrained MAP solution reduces to the conventional unconstrained MAP 3D surface reconstruction solution if the rate constraint is loose. To solve our posed rate-constrained estimation problem, we propose an iterative algorithm, where in each iteration the structure (object boundaries) and the texture (surfaces within the object boundaries) of the depth maps are optimized alternately. Using the MVC codec for compression of multiview depth video and MPEG free viewpoint video sequences as input, experimental results show that rate-constrained estimated 3D surfaces computed by our algorithm can reduce coding rate of depth maps by up to 32% compared with unconstrained estimated surfaces for the same quality of synthesized virtual views at the decoder. PMID:24876124

  3. 3D Geological Model of Nihe ore deposit Constrained by Gravity and Magnetic Modeling

    NASA Astrophysics Data System (ADS)

    Qi, Guang; Yan, Jiayong; Lv, Qingtan; Zhao, Jinhua

    2016-04-01

    observed data, and then adjust the model until a satisfactory accuracy of errors is achieved. It is hope that this work can provide reference for similar work in other areas. this study shows that the research of geologic constrained 3D gravity and magnetic modeling has potential value in the aspects of deep mineral exploration and mineral reserves estimation.

  4. Delaunay-Object-Dynamics: cell mechanics with a 3D kinetic and dynamic weighted Delaunay-triangulation.

    PubMed

    Meyer-Hermann, Michael

    2008-01-01

    Mathematical methods in Biology are of increasing relevance for understanding the control and the dynamics of biological systems with medical relevance. In particular, agent-based methods turn more and more important because of fast increasing computational power which makes even large systems accessible. An overview of different mathematical methods used in Theoretical Biology is provided and a novel agent-based method for cell mechanics based on Delaunay-triangulations and Voronoi-tessellations is explained in more detail: The Delaunay-Object-Dynamics method. It is claimed that the model combines physically realistic cell mechanics with a reasonable computational load. The power of the approach is illustrated with two examples, avascular tumor growth and genesis of lymphoid tissue in a cell-flow equilibrium. PMID:18023735

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

    NASA Astrophysics Data System (ADS)

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

    2014-12-01

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

  6. 3D automatic liver segmentation using feature-constrained Mahalanobis distance in CT images.

    PubMed

    Salman Al-Shaikhli, Saif Dawood; Yang, Michael Ying; Rosenhahn, Bodo

    2016-08-01

    Automatic 3D liver segmentation is a fundamental step in the liver disease diagnosis and surgery planning. This paper presents a novel fully automatic algorithm for 3D liver segmentation in clinical 3D computed tomography (CT) images. Based on image features, we propose a new Mahalanobis distance cost function using an active shape model (ASM). We call our method MD-ASM. Unlike the standard active shape model (ST-ASM), the proposed method introduces a new feature-constrained Mahalanobis distance cost function to measure the distance between the generated shape during the iterative step and the mean shape model. The proposed Mahalanobis distance function is learned from a public database of liver segmentation challenge (MICCAI-SLiver07). As a refinement step, we propose the use of a 3D graph-cut segmentation. Foreground and background labels are automatically selected using texture features of the learned Mahalanobis distance. Quantitatively, the proposed method is evaluated using two clinical 3D CT scan databases (MICCAI-SLiver07 and MIDAS). The evaluation of the MICCAI-SLiver07 database is obtained by the challenge organizers using five different metric scores. The experimental results demonstrate the availability of the proposed method by achieving an accurate liver segmentation compared to the state-of-the-art methods. PMID:26501155

  7. An unstaggered constrained transport method for the 3D ideal magnetohydrodynamic equations

    NASA Astrophysics Data System (ADS)

    Helzel, Christiane; Rossmanith, James A.; Taetz, Bertram

    2011-05-01

    Numerical methods for solving the ideal magnetohydrodynamic (MHD) equations in more than one space dimension must either confront the challenge of controlling errors in the discrete divergence of the magnetic field, or else be faced with nonlinear numerical instabilities. One approach for controlling the discrete divergence is through a so-called constrained transport method, which is based on first predicting a magnetic field through a standard finite volume solver, and then correcting this field through the appropriate use of a magnetic vector potential. In this work we develop a constrained transport method for the 3D ideal MHD equations that is based on a high-resolution wave propagation scheme. Our proposed scheme is the 3D extension of the 2D scheme developed by Rossmanith [J.A. Rossmanith, An unstaggered, high-resolution constrained transport method for magnetohydrodynamic flows, SIAM J. Sci. Comput. 28 (2006) 1766], and is based on the high-resolution wave propagation method of Langseth and LeVeque [J.O. Langseth, R.J. LeVeque, A wave propagation method for threedimensional hyperbolic conservation laws, J. Comput. Phys. 165 (2000) 126]. In particular, in our extension we take great care to maintain the three most important properties of the 2D scheme: (1) all quantities, including all components of the magnetic field and magnetic potential, are treated as cell-centered; (2) we develop a high-resolution wave propagation scheme for evolving the magnetic potential; and (3) we develop a wave limiting approach that is applied during the vector potential evolution, which controls unphysical oscillations in the magnetic field. One of the key numerical difficulties that is novel to 3D is that the transport equation that must be solved for the magnetic vector potential is only weakly hyperbolic. In presenting our numerical algorithm we describe how to numerically handle this problem of weak hyperbolicity, as well as how to choose an appropriate gauge condition. The

  8. 3D unconstrained and geologically constrained stochastic inversion of airborne vertical gravity gradient data

    NASA Astrophysics Data System (ADS)

    Tchikaya, Euloge Budet; Chouteau, Michel; Keating, Pierre; Shamsipour, Pejman

    2016-02-01

    We present an inversion tool for airborne gravity gradient data that yields a 3D density model using stochastic methods i.e. cokriging and conditional simulation. This method uses geostatistical properties of the measured gravity gradient to estimate a 3D density model whose gravity response fits the measured gravity gradient anomaly. Linearity between gravity gradient data and density allows estimation of the model (density) covariance using observed data, i.e. we adjust iteratively the density covariance matrix by fitting experimental and theoretical gravity gradient covariance matrices. Inversion can be constrained by including densities known at some locations. In addition we can explore various reasonable solutions that honour both the estimated density covariance model and the gravity gradient data using geostatistical simulation. The proposed method is first tested with two synthetic datasets generated from a sharp-boundary model and a smooth stochastic model respectively. The results show the method to be capable of retrieving models compatible with the true models; it also allows the integration of complex a priori information. The technique is then applied to gravity gradient survey data collected for the Geological Survey of Canada in the area of McFaulds Lake (Ontario, Canada) using the Falcon airborne gravity system. Unconstrained inversion returns a density model that is geologically plausible and the computed response exactly fits the observed gravity gradient anomaly.

  9. Statistical 3D Prostate Imaging Atlas Construction via Anatomically Constrained Registration

    PubMed Central

    Rusu, Mirabela; Bloch, B. Nicolas; Jaffe, Carl C.; Rofsky, Neil M.; Genega, Elizabeth M.; Feleppa, Ernest; Lenkinski, Robert E.; Madabhushi, Anant

    2013-01-01

    Statistical imaging atlases allow for integration of information from multiple patient studies collected across different image scales and modalities, such as multi-parametric (MP) MRI and histology, providing population statistics regarding a specific pathology within a single canonical representation. Such atlases are particularly valuable in the identification and validation of meaningful imaging signatures for disease characterization in vivo within a population. Despite the high incidence of prostate cancer, an imaging atlas focused on different anatomic structures of the prostate, i.e. an anatomic atlas, has yet to be constructed. In this work we introduce a novel framework for MRI atlas construction that uses an iterative, anatomically constrained registration (AnCoR) scheme to enable the proper alignment of the prostate (Pr) and central gland (CG) boundaries. Our current implementation uses endorectal, 1.5T or 3T, T2-weighted MRI from 51 patients with biopsy confirmed cancer; however, the prostate atlas is seamlessly extensible to include additional MRI parameters. In our cohort, radical prostatectomy is performed following MP-MR image acquisition; thus ground truth annotations for prostate cancer are available from the histological specimens. Once mapped onto MP-MRI through elastic registration of histological slices to corresponding T2-w MRI slices, the annotations are utilized by the AnCoR framework to characterize the 3D statistical distribution of cancer per anatomic structure. Such distributions are useful for guiding biopsies toward regions of higher cancer likelihood and understanding imaging profiles for disease extent in vivo. We evaluate our approach via the Dice similarity coefficient (DSC) for different anatomic structures (delineated by expert radiologists): Pr, CG and peripheral zone (PZ). The AnCoR-based atlas had a CG DSC of 90.36%, and Pr DSC of 89.37%. Moreover, we evaluated the deviation of anatomic landmarks, the urethra and

  10. A 3-D density model of Greece constrained by gravity and seismic data

    NASA Astrophysics Data System (ADS)

    Makris, Jannis; Papoulia, Joanna; Yegorova, Tamara

    2013-07-01

    A 3-D density model of Greece was developed by gravity modelling constrained by 2-D seismic profiles. Densities were defined from seismic velocities using the Nafe & Drake and Birch empirical functions for the sediments, crust and upper mantle. Sediments in the North Aegean are 6 km thick, and are deposited in transtensional basins developing by dextral strike slip motion of the North Anatolian Fault. The Cyclades, central Aegean Sea, are free of sediments. South of Crete, in the Libyan Sea, sediments are approximately 11 km thick. At the western Hellenides sediments of up to 8 km thickness have been accumulated in basins formed by crustal bending and southwestwards thrusting of the Hellenic napes. At a deeper crustal level variations of crustal type and thickness cause density variations explaining large part of the observed gravity field. The North Aegean domain is characterized by a 24-km-thick continental crust, including sediments, whereas the western Cyclades, in central Aegean area, have a slightly thickened crust of 26 km. Crustal thicknesses vary between 16 km in the deep Ionian and Cretan Seas to 40 km in the western Hellenides. In western Crete crust is 30-32 km thick, thinning eastwards to only 26 km. The deep Ionian basin, the Mediterranean Ridge, as well as most of the Libyan Sea are underlain by oceanic crust. In western Turkey the crust thickens from 30 km along the coast to 34 km to the interior. A third deeper level of density variations occurs in the upper mantle. Subduction of the oceanic lithosphere below the Aegean continental domain destabilizes the thermal field, uplifting the isotherms by convection and conduction below the Aegean Sea. Consequently, volume expansion of the upper mantle and lithological changes reduce its density and depress the gravity intensity. This low density-velocity upper mantle extends from the Sporades islands in the North Aegean to the Cretan Sea, occupying the space between the cold subducted Ionian oceanic

  11. Statistical 3D prostate imaging atlas construction via anatomically constrained registration

    NASA Astrophysics Data System (ADS)

    Rusu, Mirabela; Bloch, B. Nicolas; Jaffe, Carl C.; Rofsky, Neil M.; Genega, Elizabeth M.; Feleppa, Ernest; Lenkinski, Robert E.; Madabhushi, Anant

    2013-03-01

    Statistical imaging atlases allow for integration of information from multiple patient studies collected across different image scales and modalities, such as multi-parametric (MP) MRI and histology, providing population statistics regarding a specific pathology within a single canonical representation. Such atlases are particularly valuable in the identification and validation of meaningful imaging signatures for disease characterization in vivo within a population. Despite the high incidence of prostate cancer, an imaging atlas focused on different anatomic structures of the prostate, i.e. an anatomic atlas, has yet to be constructed. In this work we introduce a novel framework for MRI atlas construction that uses an iterative, anatomically constrained registration (AnCoR) scheme to enable the proper alignment of the prostate (Pr) and central gland (CG) boundaries. Our current implementation uses endorectal, 1.5T or 3T, T2-weighted MRI from 51 patients with biopsy confirmed cancer; however, the prostate atlas is seamlessly extensible to include additional MRI parameters. In our cohort, radical prostatectomy is performed following MP-MR image acquisition; thus ground truth annotations for prostate cancer are available from the histological specimens. Once mapped onto MP-MRI through elastic registration of histological slices to corresponding T2-w MRI slices, the annotations are utilized by the AnCoR framework to characterize the 3D statistical distribution of cancer per anatomic structure. Such distributions are useful for guiding biopsies toward regions of higher cancer likelihood and understanding imaging profiles for disease extent in vivo. We evaluate our approach via the Dice similarity coefficient (DSC) for different anatomic structures (delineated by expert radiologists): Pr, CG and peripheral zone (PZ). The AnCoR-based atlas had a CG DSC of 90.36%, and Pr DSC of 89.37%. Moreover, we evaluated the deviation of anatomic landmarks, the urethra and

  12. The lithospheric-scale 3D structural configuration of the North Alpine Foreland Basin constrained by gravity modelling and the calculation of the 3D load distribution

    NASA Astrophysics Data System (ADS)

    Przybycin, Anna M.; Scheck-Wenderoth, Magdalena; Schneider, Michael

    2014-05-01

    The North Alpine Foreland Basin is situated in the northern front of the European Alps and extends over parts of France, Switzerland, Germany and Austria. It formed as a wedge shaped depression since the Tertiary in consequence of the Euro - Adriatic continental collision and the Alpine orogeny. The basin is filled with clastic sediments, the Molasse, originating from erosional processes of the Alps and underlain by Mesozoic sedimentary successions and a Paleozoic crystalline crust. For our study we have focused on the German part of the basin. To investigate the deep structure, the isostatic state and the load distribution of this region we have constructed a 3D structural model of the basin and the Alpine area using available depth and thickness maps, regional scale 3D structural models as well as seismic and well data for the sedimentary part. The crust (from the top Paleozoic down to the Moho (Grad et al. 2008)) has been considered as two-parted with a lighter upper crust and a denser lower crust; the partition has been calculated following the approach of isostatic equilibrium of Pratt (1855). By implementing a seismic Lithosphere-Asthenosphere-Boundary (LAB) (Tesauro 2009) the crustal scale model has been extended to the lithospheric-scale. The layer geometry and the assigned bulk densities of this starting model have been constrained by means of 3D gravity modelling (BGI, 2012). Afterwards the 3D load distribution has been calculated using a 3D finite element method. Our results show that the North Alpine Foreland Basin is not isostatically balanced and that the configuration of the crystalline crust strongly controls the gravity field in this area. Furthermore, our results show that the basin area is influenced by varying lateral load differences down to a depth of more than 150 km what allows a first order statement of the required compensating horizontal stress needed to prevent gravitational collapse of the system. BGI (2012). The International

  13. Automatic 3D kidney segmentation based on shape constrained GC-OAAM

    NASA Astrophysics Data System (ADS)

    Chen, Xinjian; Summers, Ronald M.; Yao, Jianhua

    2011-03-01

    The kidney can be classified into three main tissue types: renal cortex, renal medulla and renal pelvis (or collecting system). Dysfunction of different renal tissue types may cause different kidney diseases. Therefore, accurate and efficient segmentation of kidney into different tissue types plays a very important role in clinical research. In this paper, we propose an automatic 3D kidney segmentation method which segments the kidney into the three different tissue types: renal cortex, medulla and pelvis. The proposed method synergistically combines active appearance model (AAM), live wire (LW) and graph cut (GC) methods, GC-OAAM for short. Our method consists of two main steps. First, a pseudo 3D segmentation method is employed for kidney initialization in which the segmentation is performed slice-by-slice via a multi-object oriented active appearance model (OAAM) method. An improved iterative model refinement algorithm is proposed for the AAM optimization, which synergistically combines the AAM and LW method. Multi-object strategy is applied to help the object initialization. The 3D model constraints are applied to the initialization result. Second, the object shape information generated from the initialization step is integrated into the GC cost computation. A multi-label GC method is used to segment the kidney into cortex, medulla and pelvis. The proposed method was tested on 19 clinical arterial phase CT data sets. The preliminary results showed the feasibility and efficiency of the proposed method.

  14. Reconstruction for 3D PET Based on Total Variation Constrained Direct Fourier Method

    PubMed Central

    Yu, Haiqing; Chen, Zhi; Zhang, Heye; Loong Wong, Kelvin Kian; Chen, Yunmei; Liu, Huafeng

    2015-01-01

    This paper presents a total variation (TV) regularized reconstruction algorithm for 3D positron emission tomography (PET). The proposed method first employs the Fourier rebinning algorithm (FORE), rebinning the 3D data into a stack of ordinary 2D data sets as sinogram data. Then, the resulted 2D sinogram are ready to be reconstructed by conventional 2D reconstruction algorithms. Given the locally piece-wise constant nature of PET images, we introduce the total variation (TV) based reconstruction schemes. More specifically, we formulate the 2D PET reconstruction problem as an optimization problem, whose objective function consists of TV norm of the reconstructed image and the data fidelity term measuring the consistency between the reconstructed image and sinogram. To solve the resulting minimization problem, we apply an efficient methods called the Bregman operator splitting algorithm with variable step size (BOSVS). Experiments based on Monte Carlo simulated data and real data are conducted as validations. The experiment results show that the proposed method produces higher accuracy than conventional direct Fourier (DF) (bias in BOSVS is 70% of ones in DF, variance of BOSVS is 80% of ones in DF). PMID:26398232

  15. PDE constrained optimization of electrical defibrillation in a 3D ventricular slice geometry.

    PubMed

    Chamakuri, Nagaiah; Kunisch, Karl; Plank, Gernot

    2016-04-01

    A computational study of an optimal control approach for cardiac defibrillation in a 3D geometry is presented. The cardiac bioelectric activity at the tissue and bath volumes is modeled by the bidomain model equations. The model includes intramural fiber rotation, axially symmetric around the fiber direction, and anisotropic conductivity coefficients, which are extracted from a histological image. The dynamics of the ionic currents are based on the regularized Mitchell-Schaeffer model. The controls enter in the form of electrodes, which are placed at the boundary of the bath volume with the goal of dampening undesired arrhythmias. The numerical optimization is based on Newton techniques. We demonstrated the parallel architecture environment for the computation of potentials on multidomains and for the higher order optimization techniques. Copyright © 2015 John Wiley & Sons, Ltd. PMID:26249168

  16. 3D pulse EPR imaging from sparse-view projections via constrained, total variation minimization

    NASA Astrophysics Data System (ADS)

    Qiao, Zhiwei; Redler, Gage; Epel, Boris; Qian, Yuhua; Halpern, Howard

    2015-09-01

    Tumors and tumor portions with low oxygen concentrations (pO2) have been shown to be resistant to radiation therapy. As such, radiation therapy efficacy may be enhanced if delivered radiation dose is tailored based on the spatial distribution of pO2 within the tumor. A technique for accurate imaging of tumor oxygenation is critically important to guide radiation treatment that accounts for the effects of local pO2. Electron paramagnetic resonance imaging (EPRI) has been considered one of the leading methods for quantitatively imaging pO2 within tumors in vivo. However, current EPRI techniques require relatively long imaging times. Reducing the number of projection scan considerably reduce the imaging time. Conventional image reconstruction algorithms, such as filtered back projection (FBP), may produce severe artifacts in images reconstructed from sparse-view projections. This can lower the utility of these reconstructed images. In this work, an optimization based image reconstruction algorithm using constrained, total variation (TV) minimization, subject to data consistency, is developed and evaluated. The algorithm was evaluated using simulated phantom, physical phantom and pre-clinical EPRI data. The TV algorithm is compared with FBP using subjective and objective metrics. The results demonstrate the merits of the proposed reconstruction algorithm.

  17. 3D pulse EPR imaging from sparse-view projections via constrained, total variation minimization

    PubMed Central

    Qiao, Zhiwei; Redler, Gage; Epel, Boris; Halpern, Howard

    2016-01-01

    Tumors and tumor portions with low oxygen concentrations (pO2) have been shown to be resistant to radiation therapy. As such, radiation therapy efficacy may be enhanced if delivered radiation dose is tailored based on the spatial distribution of pO2 within the tumor. A technique for accurate imaging of tumor oxygenation is critically important to guide radiation treatment that accounts for the effects of local pO2. Electron paramagnetic resonance imaging (EPRI) has been considered one of the leading methods for quantitatively imaging pO2 within tumors in vivo. However, current EPRI techniques require relatively long imaging times. Reducing the number of projections can considerably reduce the imaging time. Conventional image reconstruction algorithms, such as filtered back projection (FBP), may produce severe artifacts in images reconstructed from sparse-view projections. This can lower the utility of these reconstructed images. In this work, an optimization based image reconstruction algorithm using constrained, total variation (TV) minimization, subject to data consistency, is developed and evaluated. The algorithm was evaluated using simulated phantom, physical phantom and pre-clinical EPRI data. The TV algorithm is compared with FBP using subjective and objective metrics. The results demonstrate the merits of the proposed reconstruction algorithm. PMID:26225440

  18. A 3-D constrained mixture model for mechanically mediated vascular growth and remodeling

    PubMed Central

    Wan, William; Hansen, Laura

    2010-01-01

    In contrast to the widely applied approach to model soft tissue remodeling employing the concept of volumetric growth, microstructurally motivated models are capable of capturing many of the underlying mechanisms of growth and remodeling; i.e., the production, removal, and remodeling of individual constituents at different rates and to different extents. A 3-dimensional constrained mixture computational framework has been developed for vascular growth and remodeling, considering new, microstructurally motivated kinematics and constitutive equations and new stress and muscle activation mediated evolution equations. Our computational results for alterations in flow and pressure, using reasonable physiological values for rates of constituent growth and turnover, concur with findings in the literature. For example, for flow-induced remodeling, our simulations predict that, although the wall shear stress is restored completely, the circumferential stress is not restored employing realistic physiological rate parameters. Also, our simulations predict different levels of thickening on inner versus outer wall locations, as shown in numerous reports of pressure-induced remodeling. Whereas the simulations are meant to be illustrative, they serve to highlight the experimental data currently lacking to fully quantify mechanically mediated adaptations in the vasculature. PMID:20039091

  19. Development of Kinematic 3D Laser Scanning System for Indoor Mapping and As-Built BIM Using Constrained SLAM

    PubMed Central

    Jung, Jaehoon; Yoon, Sanghyun; Ju, Sungha; Heo, Joon

    2015-01-01

    The growing interest and use of indoor mapping is driving a demand for improved data-acquisition facility, efficiency and productivity in the era of the Building Information Model (BIM). The conventional static laser scanning method suffers from some limitations on its operability in complex indoor environments, due to the presence of occlusions. Full scanning of indoor spaces without loss of information requires that surveyors change the scanner position many times, which incurs extra work for registration of each scanned point cloud. Alternatively, a kinematic 3D laser scanning system, proposed herein, uses line-feature-based Simultaneous Localization and Mapping (SLAM) technique for continuous mapping. Moreover, to reduce the uncertainty of line-feature extraction, we incorporated constrained adjustment based on an assumption made with respect to typical indoor environments: that the main structures are formed of parallel or orthogonal line features. The superiority of the proposed constrained adjustment is its reduction for uncertainties of the adjusted lines, leading to successful data association process. In the present study, kinematic scanning with and without constrained adjustment were comparatively evaluated in two test sites, and the results confirmed the effectiveness of the proposed system. The accuracy of the 3D mapping result was additionally evaluated by comparison with the reference points acquired by a total station: the Euclidean average distance error was 0.034 m for the seminar room and 0.043 m for the corridor, which satisfied the error tolerance for point cloud acquisition (0.051 m) according to the guidelines of the General Services Administration for BIM accuracy. PMID:26501292

  20. Development of kinematic 3D laser scanning system for indoor mapping and as-built BIM using constrained SLAM.

    PubMed

    Jung, Jaehoon; Yoon, Sanghyun; Ju, Sungha; Heo, Joon

    2015-01-01

    The growing interest and use of indoor mapping is driving a demand for improved data-acquisition facility, efficiency and productivity in the era of the Building Information Model (BIM). The conventional static laser scanning method suffers from some limitations on its operability in complex indoor environments, due to the presence of occlusions. Full scanning of indoor spaces without loss of information requires that surveyors change the scanner position many times, which incurs extra work for registration of each scanned point cloud. Alternatively, a kinematic 3D laser scanning system, proposed herein, uses line-feature-based Simultaneous Localization and Mapping (SLAM) technique for continuous mapping. Moreover, to reduce the uncertainty of line-feature extraction, we incorporated constrained adjustment based on an assumption made with respect to typical indoor environments: that the main structures are formed of parallel or orthogonal line features. The superiority of the proposed constrained adjustment is its reduction for uncertainties of the adjusted lines, leading to successful data association process. In the present study, kinematic scanning with and without constrained adjustment were comparatively evaluated in two test sites, and the results confirmed the effectiveness of the proposed system. The accuracy of the 3D mapping result was additionally evaluated by comparison with the reference points acquired by a total station: the Euclidean average distance error was 0.034 m for the seminar room and 0.043 m for the corridor, which satisfied the error tolerance for point cloud acquisition (0.051 m) according to the guidelines of the General Services Administration for BIM accuracy. PMID:26501292

  1. Constraining the Absolute Orientation of eta Carinae's Binary Orbit: A 3-D Dynamical Model for the Broad [Fe III] Emission

    NASA Technical Reports Server (NTRS)

    Madura, T. I.; Gull, T. R.; Owocki, S. P.; Groh, J. H.; Okazaki, A. T.; Russell, C. M. P.

    2011-01-01

    We present a three-dimensional (3-D) dynamical model for the broad [Fe III] emission observed in Eta Carinae using the Hubble Space Telescope/Space Telescope Imaging Spectrograph (HST/STIS). This model is based on full 3-D Smoothed Particle Hydrodynamics (SPH) simulations of Eta Car's binary colliding winds. Radiative transfer codes are used to generate synthetic spectro-images of [Fe III] emission line structures at various observed orbital phases and STIS slit position angles (PAs). Through a parameter study that varies the orbital inclination i, the PA(theta) that the orbital plane projection of the line-of-sight makes with the apastron side of the semi-major axis, and the PA on the sky of the orbital axis, we are able, for the first time, to tightly constrain the absolute 3-D orientation of the binary orbit. To simultaneously reproduce the blue-shifted emission arcs observed at orbital phase 0.976, STIS slit PA = +38deg, and the temporal variations in emission seen at negative slit PAs, the binary needs to have an i approx. = 130deg to 145deg, Theta approx. = -15deg to +30deg, and an orbital axis projected on the sky at a P A approx. = 302deg to 327deg east of north. This represents a system with an orbital axis that is closely aligned with the inferred polar axis of the Homunculus nebula, in 3-D. The companion star, Eta(sub B), thus orbits clockwise on the sky and is on the observer's side of the system at apastron. This orientation has important implications for theories for the formation of the Homunculus and helps lay the groundwork for orbital modeling to determine the stellar masses.

  2. Constraining the absolute orientation of η Carinae's binary orbit: a 3D dynamical model for the broad [Fe III] emission

    NASA Astrophysics Data System (ADS)

    Madura, T. I.; Gull, T. R.; Owocki, S. P.; Groh, J. H.; Okazaki, A. T.; Russell, C. M. P.

    2012-03-01

    We present a three-dimensional (3D) dynamical model for the broad [Fe III] emission observed in η Carinae using the Hubble Space Telescope/Space Telescope Imaging Spectrograph (STIS). This model is based on full 3D smoothed particle hydrodynamics simulations of η Car's binary colliding winds. Radiative transfer codes are used to generate synthetic spectroimages of [Fe III] emission-line structures at various observed orbital phases and STIS slit position angles (PAs). Through a parameter study that varies the orbital inclination i, the PA θ that the orbital plane projection of the line of sight makes with the apastron side of the semimajor axis and the PA on the sky of the orbital axis, we are able, for the first time, to tightly constrain the absolute 3D orientation of the binary orbit. To simultaneously reproduce the blueshifted emission arcs observed at orbital phase 0.976, STIS slit PA =+38° and the temporal variations in emission seen at negative slit PAs, the binary needs to have an i≈ 130° to 145°, θ≈-15° to +30° and an orbital axis projected on the sky at a PA ≈ 302° to 327° east of north. This represents a system with an orbital axis that is closely aligned with the inferred polar axis of the Homunculus nebula, in 3D. The companion star, ηB, thus orbits clockwise on the sky and is on the observer's side of the system at apastron. This orientation has important implications for theories for the formation of the Homunculus and helps lay the groundwork for orbital modelling to determine the stellar masses. Footnotes<label>1</label>Low- and high-ionization refer here to atomic species with ionizations potentials (IPs) below and above the IP of hydrogen, 13.6 eV.<label>2</label>Measured in degrees from north to east.<label>3</label>θ is the same as the angle φ defined in fig. 3 of O08.<label>4</label>The outer edge looks circular only because this marks the edge of the spherical computational domain of the SPH simulation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..1711838H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..1711838H"><span id="translatedtitle">The Derivation of Fault Volumetric Properties from <span class="hlt">3</span><span class="hlt">D</span> Trace Maps Using Outcrop <span class="hlt">Constrained</span> Discrete Fracture Network Models</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hodgetts, David; Seers, Thomas</p> <p>2015-04-01</p> <p>-deterministic, outcrop <span class="hlt">constrained</span> discrete fracture network modeling code to derive volumetric fault intensity measures (fault area per unit volume / fault volume per unit volume). Producing per-vertex measures of volumetric intensity; our method captures the spatial variability in <span class="hlt">3</span><span class="hlt">D</span> fault density across a surveyed outcrop, enabling first order controls to be probed. We demonstrate our approach on pervasively faulted exposures of a Permian aged reservoir analogue from the Vale of Eden Basin, UK.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.2913J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.2913J"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> imaging of soil apparent electrical conductivity from VERIS data using a 1D spatially <span class="hlt">constrained</span> inversion algorithm</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jesús Moral García, Francisco; Rebollo Castillo, Francisco Javier; Monteiro Santos, Fernando</p> <p>2016-04-01</p> <p>Maps of apparent electrical conductivity of the soil are commonly used in precision agriculture to indirectly characterize some important properties like salinity, water, and clay content. Traditionally, these studies are made through an empirical relationship between apparent electrical conductivity and properties measured in soil samples collected at a few locations in the experimental area and at a few selected depths. Recently, some authors have used not the apparent conductivity values but the soil bulk conductivity (in 2D or <span class="hlt">3</span><span class="hlt">D</span>) calculated from measured apparent electrical conductivity through the application of an inversion method. All the published works used data collected with electromagnetic (EM) instruments. We present a new software to invert the apparent electrical conductivity data collected with VERIS 3100 and 3150 (or the more recent version with three pairs of electrodes) using the 1D spatially <span class="hlt">constrained</span> inversion method (1D SCI). The software allows the calculation of the distribution of the bulk electrical conductivity in the survey area till a depth of 1 m. The algorithm is applied to experimental data and correlations with clay and water content have been established using soil samples collected at some boreholes. Keywords: Digital soil mapping; inversion modelling; VERIS; soil apparent electrical conductivity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..1213013P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..1213013P"><span id="translatedtitle">Using 1-to-<span class="hlt">3</span><span class="hlt">D</span> modeling approach to <span class="hlt">constrain</span> thermomechanical evolution of the Dead Sea Transform region</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Petrunin, Alexey G.; Meneses Rioseco, Ernesto; Sobolev, Stephan V.</p> <p>2010-05-01</p> <p> (BBS) approach (Petrunin and Sobolev, Geology 2006, PEPI 2008) and estimate the present-day thickness of the brittle layer near the DST as 20-22 km. As a result of the 2.5 D modeling, we significantly narrow down the ranges of model parameters. At the final stage we check the obtained parameters using the <span class="hlt">3</span><span class="hlt">D</span> model of the Dead Sea basin similar to (Petrunin and Sobolev, Geology 2006) that gives good correlation with the sedimentary subsidence rate and present-day geometry of the basin.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2015AGUFMIN13A1819Y&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2015AGUFMIN13A1819Y&link_type=ABSTRACT"><span id="translatedtitle">Building continental-scale <span class="hlt">3</span><span class="hlt">D</span> subsurface layers in the Digital Crust project: <span class="hlt">constrained</span> interpolation and uncertainty estimation.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yulaeva, E.; Fan, Y.; Moosdorf, N.; Richard, S. M.; Bristol, S.; Peters, S. E.; Zaslavsky, I.; Ingebritsen, S.</p> <p>2015-12-01</p> <p>The Digital Crust EarthCube building block creates a framework for integrating disparate <span class="hlt">3</span><span class="hlt">D</span>/4D information from multiple sources into a comprehensive model of the structure and composition of the Earth's upper crust, and to demonstrate the utility of this model in several research scenarios. One of such scenarios is estimation of various crustal properties related to fluid dynamics (e.g. permeability and porosity) at each node of any arbitrary unstructured <span class="hlt">3</span><span class="hlt">D</span> grid to support continental-scale numerical models of fluid flow and transport. Starting from Macrostrat, an existing 4D database of 33,903 chronostratigraphic units, and employing GeoDeepDive, a software system for extracting structured information from unstructured documents, we construct <span class="hlt">3</span><span class="hlt">D</span> gridded fields of sediment/rock porosity, permeability and geochemistry for large sedimentary basins of North America, which will be used to improve our understanding of large-scale fluid flow, chemical weathering rates, and geochemical fluxes into the ocean. In this talk, we discuss the methods, data gaps (particularly in geologically complex terrain), and various physical and geological constraints on interpolation and uncertainty estimation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/219612','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/219612"><span id="translatedtitle">Preconditioning techniques for <span class="hlt">constrained</span> vector potential integral equations, with application to <span class="hlt">3</span>-<span class="hlt">D</span> magnetoquasistatic analysis of electronic packages</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kamon, M.; Phillips, J.R.</p> <p>1994-12-31</p> <p>In this paper techniques are presented for preconditioning equations generated by discretizing <span class="hlt">constrained</span> vector integral equations associated with magnetoquasistatic analysis. Standard preconditioning approaches often fail on these problems. The authors present a specialized preconditioning technique and prove convergence bounds independent of the constraint equations and electromagnetic excitation frequency. Computational results from analyzing several electronic packaging examples are given to demonstrate that the new preconditioning approach can sometimes reduce the number of GMRES iterations by more than an order of magnitude.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.H41K..08H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.H41K..08H"><span id="translatedtitle">Incorporating Sedimentological Observations, Hydrogeophysics and conceptual Knowledge to <span class="hlt">Constrain</span> <span class="hlt">3</span><span class="hlt">D</span> Numerical Heterogeneity Models of Coarse Alluvial Systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Huber, E.; Huggenberger, P.</p> <p>2012-12-01</p> <p>Accurate predictions on groundwater flow and transport behavior within fluvial and glaciofluvial sediments, but also interaction with surface water bodies, rely on knowledge of distributed aquifer properties. The complexity of the depositional and erosional processes in fluvial systems leads to highly heterogeneous distributions of hydrogeological parameters. The system dynamics, such as aggradation rates and channel mobility of alluvial systems; its influence on the preservation potential of the key depositional elements in the geological record; and its influence on the heterogeneity scales and the relevance for groundwater hydraulics is topic of the presentation. The aims of our work are to find a relation between surface morphological structures and the sedimentary structures in vertical profiles (i.e. gravel pits or GPR sections) and to derive rules for the interpretation of horizontal time-slices from <span class="hlt">3</span><span class="hlt">D</span> GPR data. Based on these data we set-up conceptual models of the structures of coarse alluvial systems at different scales which can be tested by stochastic methods. Relevant depositional elements and a hierarchy or genetic relationship of such elements will be defined based on the knowledge of depositional processes in alluvial systems inferred from: field observations after major flood events; 2D and <span class="hlt">3</span><span class="hlt">D</span> GPR data; and from existing data derived from laboratory flumes. Extensive geophysical field experiments within the Tagliamento alluvial system gave new insights to the sedimentary structures developing at high flows. Owing to the fact that rivers often destroy at least part of their bed during or shortly after large floods and subsequently rebuild, it is not easy to establish a simple relationship between surface morphology and the sedimentary structures found in vertical sections of many alluvial outcrops. According to these findings we suppose that surface or near-surface structures will not catch the essence of heterogeneity of alluvial aquifers</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.T11F..07S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.T11F..07S"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> thermo-mechanical model of the orogeny in Pamir <span class="hlt">constrained</span> by geological and geophysical observations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sobolev, S. V.; Tympel, J.; Ratschbacher, L.</p> <p>2015-12-01</p> <p>The Pamir-Hindu Kush orogenic belt is the result of the indentation of the western corner of the India plate into Eurasia. It has accommodated the highest strain over the shortest meridional distance of the India-Eurasia collision zone. Recent high-resolution seismic tomographic and receiver function studies confirm the presence of a south-dipping continental lithosphere, which has been traced to the depth of more than 200-300 km beneath the northern Pamir (Pamir slab). Balanced cross-section document crustal shortening associated with the corresponding frontal thrust system of a few tens of km, which is much less than the expected (>200-300 km) for intra-continental subduction zone, based on the seismically imaged length of the Pamir slab. Another unique feature of Pamir is the presence of large gneiss domes with the exhumation reaching a depth of 30-40 km.We employ the finite-element thermomechanical modelling technique SLIM<span class="hlt">3</span><span class="hlt">D</span> to simulate the evolution of the Pamir orogeny during the last 25 Myr. The technique is using advanced non-linear elasto-visco-plastic rheology with parameters based on laboratory experiments. Our <span class="hlt">3</span><span class="hlt">D</span> model extends 1100 km N-S, 800 km E-W, and 300 km deep, and replicates indentation of the western half of India promontory into Eurasia. The moving modelling-window technique allows focusing at the most extensively deforming domains, and a <span class="hlt">3</span><span class="hlt">D</span> model setup and boundary conditions allow lateral material flow to the west, i.e. perpendicular to the direction of tectonic shortening.The model replicates major features of the lithospheric structure and geological history. For instance, we demonstrate that large part of the roll back of the Pamir slab may be caused by the delamination of the mantle lithosphere together with the lower crust, rather than classical intra-continental subduction involving thrust-imbrication of the uppermost crust. The resulting shortening at the Pamir frontal thrust system appears to be lower than 50 km in accord with</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.S11B..06S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.S11B..06S"><span id="translatedtitle">Crust Uppermost Mantle Structure beneath Eastern Asia: Progress towards a Uniform, Tightly <span class="hlt">Constrained</span>, High Resolution <span class="hlt">3</span>-<span class="hlt">D</span> Model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shen, W.; Ritzwoller, M. H.; Zheng, Y.; Lin, F. C.; Kim, Y.; Ning, J.; Kang, D.; Feng, L.; Wiens, D. A.</p> <p>2015-12-01</p> <p>In the past decade, large and dense seismic arrays have been deployed across much of eastern Asia (e.g., the "CEArray" and the "China Array" deployed by the China Earthquake Administration (CEA), the NECESS Array deployed collaboratively by China, Japan and the US, Korean Seismic Network, KNET and other networks in Japan, and historical PASSCAL installations), which have been used to produce increasingly well resolved models of the crust and uppermost mantle at different length scales. These models, however, do not cover eastern Asia uniformly. In this presentation, we report on an effort to generate a uniform high resolution <span class="hlt">3</span>-<span class="hlt">D</span> model of the crust and uppermost mantle beneath eastern Asia using state-of-art surface wave and body wave inversion techniques. Highlights of this effort include: 1) We collect ambient noise cross-correlations using more than 1,800 seismic stations from multiple seismic arrays in this area and perform uniform surface wave tomography for the study area. 2) We collect P-wave receiver functions for over 1,000 stations and Rayleigh wave H/V ratio measurements for over 200 stations in this area. 3) We adopt a Bayesian Monte Carlo inversion to the Rayleigh wave dispersion maps and produce a uniform <span class="hlt">3</span>-<span class="hlt">D</span> model with uncertainties of the crust and uppermost mantle. 4) In the areas where receiver functions and/or Rayleigh wave H/V ratios are collected, we replace the surface wave inversion by a joint inversion of surface waves and these seismic observables. The resulting model displays a great variety and considerable richness of geological and tectonic features in the crust and in the uppermost mantle which we summarize and discuss with focus on the relationship between the observed crustal variations and tectonic/geological boundaries and lithospheric modifications associated with volcanism in Northeast China.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.A43G3369T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.A43G3369T"><span id="translatedtitle">Developing a <span class="hlt">3</span><span class="hlt">D</span> <span class="hlt">Constrained</span> Variational Analysis Method to Calculate Large Scale Forcing Data and the Applications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tang, S.; Zhang, M. H.</p> <p>2014-12-01</p> <p>Large-scale forcing data (vertical velocities and advective tendencies) are important atmospheric fields to drive single-column models (SCM), cloud-resolving models (CRM) and large-eddy simulations (LES), but they are difficult to calculate accurately. The current 1-dimensional <span class="hlt">constrained</span> variational analysis (1D CVA) method (Zhang and Lin, 1997) used by the Atmospheric Radiation Measurement (ARM) program is limited to represent the average of a sounding network domain. We extended the original 1D CVA algorithm into 3-dimensional along with other improvements, calculated gridded large-scale forcing data, apparent heating sources (Q1) and moisture sinks (Q2), and compared with 5 reanalyses: ERA-Interim, NCEP CFSR, MERRA, JRA55 and NARR for a mid-latitude spring cyclone case. The results from a case study for in March 3rd 2000 at the Southern Great Plain (SGP) show that reanalyses generally captured the structure of the mid-latitude cyclone, but they have serious biases in the 2nd order derivative terms (divergences and horizontal derivations) at regional scales of less than a few hundred kilometers. Our algorithm provides a set of atmospheric fields consistent with the observed constraint variables at the surface and top of the atmosphere better than reanalyses. The analyzed atmospheric fields can be used in SCM, CRM and LES to provide 3-dimensional dynamical forcing, or be used to evaluate reanalyses or model simulations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22102176','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22102176"><span id="translatedtitle">Object-<span class="hlt">constrained</span> meshless deformable algorithm for high speed <span class="hlt">3</span><span class="hlt">D</span> nonrigid registration between CT and CBCT</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Chen Ting; Kim, Sung; Goyal, Sharad; Jabbour, Salma; Zhou Jinghao; Rajagopal, Gunaretnum; Haffty, Bruce; Yue Ning</p> <p>2010-01-15</p> <p>Purpose: High-speed nonrigid registration between the planning CT and the treatment CBCT data is critical for real time image guided radiotherapy (IGRT) to improve the dose distribution and to reduce the toxicity to adjacent organs. The authors propose a new fully automatic <span class="hlt">3</span><span class="hlt">D</span> registration framework that integrates object-based global and seed constraints with the grayscale-based ''demons'' algorithm. Methods: Clinical objects were segmented on the planning CT images and were utilized as meshless deformable models during the nonrigid registration process. The meshless models reinforced a global constraint in addition to the grayscale difference between CT and CBCT in order to maintain the shape and the volume of geometrically complex <span class="hlt">3</span><span class="hlt">D</span> objects during the registration. To expedite the registration process, the framework was stratified into hierarchies, and the authors used a frequency domain formulation to diffuse the displacement between the reference and the target in each hierarchy. Also during the registration of pelvis images, they replaced the air region inside the rectum with estimated pixel values from the surrounding rectal wall and introduced an additional seed constraint to robustly track and match the seeds implanted into the prostate. The proposed registration framework and algorithm were evaluated on 15 real prostate cancer patients. For each patient, prostate gland, seminal vesicle, bladder, and rectum were first segmented by a radiation oncologist on planning CT images for radiotherapy planning purpose. The same radiation oncologist also manually delineated the tumor volumes and critical anatomical structures in the corresponding CBCT images acquired at treatment. These delineated structures on the CBCT were only used as the ground truth for the quantitative validation, while structures on the planning CT were used both as the input to the registration method and the ground truth in validation. By registering the planning CT to the CBCT, a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011PMB....56.3269W&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011PMB....56.3269W&link_type=ABSTRACT"><span id="translatedtitle">A discriminative model-<span class="hlt">constrained</span> EM approach to <span class="hlt">3</span><span class="hlt">D</span> MRI brain tissue classification and intensity non-uniformity correction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wels, Michael; Zheng, Yefeng; Huber, Martin; Hornegger, Joachim; Comaniciu, Dorin</p> <p>2011-06-01</p> <p>We describe a fully automated method for tissue classification, which is the segmentation into cerebral gray matter (GM), cerebral white matter (WM), and cerebral spinal fluid (CSF), and intensity non-uniformity (INU) correction in brain magnetic resonance imaging (MRI) volumes. It combines supervised MRI modality-specific discriminative modeling and unsupervised statistical expectation maximization (EM) segmentation into an integrated Bayesian framework. While both the parametric observation models and the non-parametrically modeled INUs are estimated via EM during segmentation itself, a Markov random field (MRF) prior model regularizes segmentation and parameter estimation. Firstly, the regularization takes into account knowledge about spatial and appearance-related homogeneity of segments in terms of pairwise clique potentials of adjacent voxels. Secondly and more importantly, patient-specific knowledge about the global spatial distribution of brain tissue is incorporated into the segmentation process via unary clique potentials. They are based on a strong discriminative model provided by a probabilistic boosting tree (PBT) for classifying image voxels. It relies on the surrounding context and alignment-based features derived from a probabilistic anatomical atlas. The context considered is encoded by <span class="hlt">3</span><span class="hlt">D</span> Haar-like features of reduced INU sensitivity. Alignment is carried out fully automatically by means of an affine registration algorithm minimizing cross-correlation. Both types of features do not immediately use the observed intensities provided by the MRI modality but instead rely on specifically transformed features, which are less sensitive to MRI artifacts. Detailed quantitative evaluations on standard phantom scans and standard real-world data show the accuracy and robustness of the proposed method. They also demonstrate relative superiority in comparison to other state-of-the-art approaches to this kind of computational task: our method achieves average</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110023552','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110023552"><span id="translatedtitle"><span class="hlt">Constraining</span> the Properties of the Eta Carinae System via <span class="hlt">3</span>-<span class="hlt">D</span> SPH Models of Space-Based Observations: The Absolute Orientation of the Binary Orbit</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Madura, Thomas I.; Gull, Theodore R.; Owocki, Stanley P.; Okazaki, Atsuo T.; Russell, Christopher M. P.</p> <p>2011-01-01</p> <p>The extremely massive (> 90 Stellar Mass) and luminous (= 5 x 10(exp 6) Stellar Luminosity) star Eta Carinae, with its spectacular bipolar "Homunculus" nebula, comprises one of the most remarkable and intensely observed stellar systems in the Galaxy. However, many of its underlying physical parameters remain unknown. Multiwavelength variations observed to occur every 5.54 years are interpreted as being due to the collision of a massive wind from the primary star with the fast, less dense wind of a hot companion star in a highly elliptical (e approx. 0.9) orbit. Using three-dimensional (<span class="hlt">3</span>-<span class="hlt">D</span>) Smoothed Particle Hydrodynamics (SPH) simulations of the binary wind-wind collision, together with radiative transfer codes, we compute synthetic spectral images of [Fe III] emission line structures and compare them to existing Hubble Space Telescope/Space Telescope Imaging Spectrograph (HST/STIS) observations. We are thus able, for the first time, to tightly <span class="hlt">constrain</span> the absolute orientation of the binary orbit on the sky. An orbit with an inclination of approx. 40deg, an argument of periapsis omega approx. 255deg, and a projected orbital axis with a position angle of approx. 312deg east of north provides the best fit to the observations, implying that the orbital axis is closely aligned in <span class="hlt">3</span>-<span class="hlt">D</span> space with the Homunculus symmetry axis, and that the companion star orbits clockwise on the sky relative to the primary.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011BSRSL..80..694M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011BSRSL..80..694M"><span id="translatedtitle"><span class="hlt">Constraining</span> the Properties of the Eta Carinae System via <span class="hlt">3</span>-<span class="hlt">D</span> SPH Models of Space-Based Observations: The Absolute Orientation of the Binary Orbit</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Madura, Thomas I.; Gull, Theodore R.; Owocki, Stanley P.; Okazaki, Atsuo T.; Russell, Christopher M. P.</p> <p>2011-01-01</p> <p>The extremely massive (> 90 M_⊙) and luminous ( = 5 × 10^{6} L_⊙) star Eta Carinae, with its spectacular bipolar ``Homunculus'' nebula, comprises one of the most remarkable and intensely observed stellar systems in the Galaxy. However, many of its underlying physical parameters remain unknown. Multiwavelength variations observed to occur every 5.54 years are interpreted as being due to the collision of a massive wind from the primary star with the fast, less dense wind of a hot companion star in a highly elliptical (e ˜ 0.9) orbit. Using three-dimensional (<span class="hlt">3</span>-<span class="hlt">D</span>) Smoothed Particle Hydrodynamics (SPH) simulations of the binary wind-wind collision, together with radiative transfer codes, we compute synthetic spectral images of [Fe III] emission line structures and compare them to existing Hubble Space Telescope/Space Telescope Imaging Spectrograph (HST/STIS) observations. We are thus able, for the first time, to tightly <span class="hlt">constrain</span> the absolute orientation of the binary orbit on the sky. An orbit with an inclination of i ˜ 40°, an argument of periapsis ω ˜ 255°, and a projected orbital axis with a position angle of ˜ 312° east of north provides the best fit to the observations, implying that the orbital axis is closely aligned in <span class="hlt">3</span>-<span class="hlt">D</span> space with the Homunculus symmetry axis, and that the companion star orbits clockwise on the sky relative to the primary.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70047785','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70047785"><span id="translatedtitle">Planimetric Martian <span class="hlt">triangulations</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Arthur, D.W.G.; McMacken, D.K.</p> <p>1977-01-01</p> <p>Narrow-angle photographs, which have severe drawbacks for stereophotogrammetry, have advantages for simple plane <span class="hlt">triangulations</span>. Rectified narrow-angle pictures corrected for map projection effects can be combined in the map plane in relatively accurate planimetric <span class="hlt">triangulations</span>. Provided the strict precepts of least squares are not followed, these <span class="hlt">triangulations</span> can incorporate considerable overdetermination without increase in the labor of solving the equations. These plane <span class="hlt">triangulations</span> have been used successfully in the cartography of Mars and are illustrated here by a <span class="hlt">triangulation</span> of the environs of the prime Martian landing site.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1992SPIE.1641...35B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1992SPIE.1641...35B"><span id="translatedtitle">Two-dimensional and <span class="hlt">3</span>-<span class="hlt">D</span> images of thick tissue using time-<span class="hlt">constrained</span> times-of-flight and absorbance spectrophotometry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Benaron, David A.; Lennox, M.; Stevenson, David K.</p> <p>1992-05-01</p> <p>Reconstructing deep-tissue images in real time using spectrophotometric data from optically diffusing thick tissues has been problematic. Continuous wave applications (e.g., pulse oximetry, regional cerebral saturation) ignore both the multiple paths traveled by the photons through the tissue and the effects of scattering, allowing scalar measurements but only under limited conditions; interferometry works poorly in thick, highly-scattering media; frequency- modulated approaches may not allow full deconvolution of scattering and absorbance; and pulsed-light techniques allow for preservation of information regarding the multiple paths taken by light through the tissue, but reconstruction is both computation intensive and limited by the relative surface area available for detection of photons. We have developed a picosecond times-of-flight and absorbance (TOFA) optical system, time-<span class="hlt">constrained</span> to measure only photons with a narrow range of path lengths and arriving within a narrow angel of the emitter-detector axis. The delay until arrival of the earliest arriving photons is a function of both the scattering and absorbance of the tissues in a direct line between the emitter and detector, reducing the influence of surrounding tissues. Measurement using a variety of emitter and detector locations produces spatial information which can be analyzed in a standard 2-D grid, or subject to computer reconstruction to produce tomographic images representing <span class="hlt">3</span>-<span class="hlt">D</span> structure. Using such a technique, we have been able to demonstrate the principles of tc-TOFA, detect and localize diffusive and/or absorptive objects suspended in highly scattering media (such as blood admixed with yeast), and perform simple <span class="hlt">3</span>-<span class="hlt">D</span> reconstructions using phantom objects. We are now attempting to obtain images in vivo. Potential future applications include use as a research tool, and as a continuous, noninvasive, nondestructive monitor in diagnostic imaging, fetal monitoring, neurologic and cardiac</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003EAEJA....10828L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003EAEJA....10828L"><span id="translatedtitle">Sedimentary basin analysis <span class="hlt">constrained</span> by <span class="hlt">3</span><span class="hlt">d</span> seismic and subsidence modelling: the case of the Phanerozoic evolution of the Dampier Sub-basin, North West Shelf of Australia.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Langhi, L.; Borel, G. D.</p> <p>2003-04-01</p> <p>The North West Shelf of Australia has been a long term passive margin, which underwent a polyphased tectonic history associated with the disintegration of Eastern Gondwana. Several Phanerozoic sedimentary basins like the Northern Carnarvon Basin developed during the rifting phases culminating in the opening of the NeoTethys during the Late Paleozoic and the abyssal plains during the Mesozoic. In order to accurately <span class="hlt">constrain</span> the Phanerozoic evolution of the proximal part of the Dampier Sub-basin (Mermaid Nose), a thorough <span class="hlt">3</span><span class="hlt">D</span> structural and stratigraphic analysis was performed on the basis of 2D/<span class="hlt">3</span><span class="hlt">D</span> seismic data. It has enabled to highlight about twenty depositional sequences from Early Permian (Late Carboniferous?) to Late Cretaceous. The cuttings description of the deepest well of the area (Roebuck-1, 2871 mRT) was (has been) interpreted on the basis of the lithological changes and 19 units were highlighted from the Kungurian Kennedy Group to the Campanian Withnell Formation. The association of the 2D/<span class="hlt">3</span><span class="hlt">D</span> seismic data and the regional Late Palaeozoic units described in the literature allows to generate a pseudo-well below Roebuck-1 total depth reaching the (Late Carboniferous?) Early Permian Lyons Group sequences. The sediments of the glacially-related Lyons Group have been interpreted on the seismic data as representing the first syntectonic infilling a half-graben. This extensional episode is linked to the NeoTethys rifting that extended up to the eastern Mediterranean area removing slivers of continents from Gondwana, known as the Cimmerian terranes. Stratigraphic, sedimentary and paleontological data provided by well and seismic analysis from the Mermaid Nose have been combined to produce subsidence curves. The subsidence modelling for the Mermaid Nose clearly emphasises the predominance of the effects of the NeoTethys rifting that took place under an ice-sheet whereas the extension coeval with the opening of the abyssal plains that occurred later and closer to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110007197','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110007197"><span id="translatedtitle"><span class="hlt">Constraining</span> the Properties of the Eta Carinae System via <span class="hlt">3</span>-<span class="hlt">D</span> SPH Models of Space-Based Observations: The Absolute Orientation of the Binary Orbit</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Madura, Thomas I.; Gull, Theodore R.; Owocki, Stanley P.; Okazaki, Atsuo T.; Russell, Christopher M. P.</p> <p>2010-01-01</p> <p>The extremely massive (> 90 Solar Mass) and luminous (= 5 x 10(exp 6) Solar Luminosity) star Eta Carinae, with its spectacular bipolar "Homunculus" nebula, comprises one of the most remarkable and intensely observed stellar systems in the galaxy. However, many of its underlying physical parameters remain a mystery. Multiwavelength variations observed to occur every 5.54 years are interpreted as being due to the collision of a massive wind from the primary star with the fast, less dense wind of a hot companion star in a highly elliptical (e approx. 0.9) orbit. Using three-dimensional (<span class="hlt">3</span>-<span class="hlt">D</span>) Smoothed Particle Hydrodynamics (SPH) simulations of the binary wind-wind collision in Eta Car, together with radiative transfer codes, we compute synthetic spectral images of [Fe III] emission line structures and compare them to existing Hubble Space Telescope/Space Telescope Imaging Spectrograph (HST/STIS) observations. We are thus able, for the first time, to <span class="hlt">constrain</span> the absolute orientation of the binary orbit on the sky. An orbit with an inclination of i approx. 40deg, an argument of periapsis omega approx. 255deg, and a projected orbital axis with a position angle of approx. 312deg east of north provides the best fit to the observations, implying that the orbital axis is closely aligned in 3-1) space with the Homunculus symmetry axis, and that the companion star orbits clockwise on the sky relative to the primary.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/983384','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/983384"><span id="translatedtitle"><span class="hlt">Triangulation</span> Made Easy</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Lindstrom, P</p> <p>2009-12-23</p> <p>We describe a simple and efficient algorithm for two-view <span class="hlt">triangulation</span> of <span class="hlt">3</span><span class="hlt">D</span> points from approximate 2D matches based on minimizing the L2 reprojection error. Our iterative algorithm improves on the one by Kanatani et al. by ensuring that in each iteration the epipolar constraint is satisfied. In the case where the two cameras are pointed in the same direction, the method provably converges to an optimal solution in exactly two iterations. For more general camera poses, two iterations are sufficient to achieve convergence to machine precision, which we exploit to devise a fast, non-iterative method. The resulting algorithm amounts to little more than solving a quadratic equation, and involves a fixed, small number of simple matrixvector operations and no conditional branches. We demonstrate that the method computes solutions that agree to very high precision with those of Hartley and Sturm's original polynomial method, though achieves higher numerical stability and 1-4 orders of magnitude greater speed.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_1");'>1</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li class="active"><span>3</span></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_13");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_3 --> <div id="page_4" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li class="active"><span>4</span></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_13");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="61"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=triangulation&id=EJ968447','ERIC'); return false;" href="http://eric.ed.gov/?q=triangulation&id=EJ968447"><span id="translatedtitle"><span class="hlt">Triangulation</span> 2.0</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Denzin, Norman K.</p> <p>2012-01-01</p> <p>The author's thesis is simple and direct. Those in the mixed methods qualitative inquiry community need a new story line, one that does not confuse pragmatism for <span class="hlt">triangulation</span>, and <span class="hlt">triangulation</span> for mixed methods research (MMR). A different third way is required, one that inspires generative politics and dialogic democracy and helps shape…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2014AGUFM.T41D..06L&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2014AGUFM.T41D..06L&link_type=ABSTRACT"><span id="translatedtitle">Compositional Density Structure of the Upper Mantle from <span class="hlt">Constrained</span> <span class="hlt">3</span>-<span class="hlt">D</span> Inversion of Gravity Anomaly: A Case Study of Southeast Asia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liang, Q.; Chen, C.; Kaban, M. K.; Thomas, M.</p> <p>2014-12-01</p> <p>Mantle density structure is a key for tectonics. The density variations in the upper mantle are affected by temperature and composition. Seismic tomography method has been widely applied to obtain the P- and S-wave velocity structure in the mantle, which is then used to calculate the density perturbation. However, the velocity model is mainly due to the thermal effects but not the compositional effects. A method of <span class="hlt">3</span>-<span class="hlt">D</span> inversion of gravity anomaly developed in spherical coordinates is used to image the large-scale density structure of upper mantle in Southeast Asia. The mantle gravity anomalies used in inversion are calculated by removing the crustal effects from the observed gravity. With constraints of thermal density model from seismic tomography, the integrative density structure is estimated from gravity inversion. Consequently, we obtain the compositional density by subtracting the thermal density from the integrative structure. The result of inversion shows the anisotropic composition of subduction zones, Cratons and plates boundary in Southeast Asia. In the shallow depth, the compositional density anomalies of large scales present uniform features in oceanic and continental mantle. In depth of 75-175 km, there are differences between the thermal and the compositional variations. The density anomalies at these depths are both affected by temperature and composition of the upper mantle. Below 175-km depth, the density anomalies are dominated by the compositional variations. Furthermore, comparing with high seismicity occurred at moderate-depth (50-300 km), we found that the compositional density variations is one of the factor that inducing earthquakes. The <span class="hlt">constrained</span> inversion of mantle gravity anomaly has possibility to reveal the subduction which is not clearly seen from low-resolution tomography data, and may reveal the relation of seismicity and composition in the upper mantle. This study is supported by the Program of International Science and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/972714','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/972714"><span id="translatedtitle">CAD Tools for Creating Space-filing <span class="hlt">3</span><span class="hlt">D</span> Escher Tiles</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Howison, Mark; Sequin, Carlo H.</p> <p>2009-04-10</p> <p>We discuss the design and implementation of CAD tools for creating decorative solids that tile 3-space in a regular, isohedral manner. Starting with the simplest case of extruded 2D tilings, we describe geometric algorithms used for maintaining boundary representations of <span class="hlt">3</span><span class="hlt">D</span> tiles, including a Java implementation of an interactive <span class="hlt">constrained</span> Delaunay <span class="hlt">triangulation</span> library and a mesh-cutting algorithm used in layering extruded tiles to create more intricate designs. Finally, we demonstrate a CAD tool for creating <span class="hlt">3</span><span class="hlt">D</span> tilings that are derived from cubic lattices. The design process for these <span class="hlt">3</span><span class="hlt">D</span> tiles is more <span class="hlt">constrained</span>, and hence more difficult, than in the 2D case, and it raises additional user interface issues.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20040111965&hterms=Nurbs&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DNurbs','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20040111965&hterms=Nurbs&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DNurbs"><span id="translatedtitle"><span class="hlt">Triangulation</span> of NURBS Surfaces</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Samareh-Abolhassani, Jamshid</p> <p>1994-01-01</p> <p>A technique is presented for <span class="hlt">triangulation</span> of NURBS surfaces. This technique is built upon an advancing front technique combined with grid point projection. This combined approach has been successfully implemented for structured and unstructured grids.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JAfES.103...71D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JAfES.103...71D"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> gravity modeling of a salt structure associated to the Trozza-Labaied lineament (Central Tunisia) <span class="hlt">constrained</span> by seismic and borehole data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Djebbi, M.; Gabtni, H.</p> <p>2015-03-01</p> <p>Gravity and seismic are two distinctive geophysical methods which are used combined in integrated geophysical studies. The rationale behind this integration is to construct a <span class="hlt">3</span><span class="hlt">D</span> gravity model for a salt structure associated to the Trozza-Labaied major tectonic deformation. The Trozza-Labaied area witnessed the occurrence of several tectonic events during the Atlassic phase resulting in the creation of various salt structures. Interpretation of the available seismic data revealed the different lithological units forming the geologic setting. Whereas the analysis of the gravity data contributed in exposing the existence of different gravity anomalies. Thus, the integrated seismic and gravity data are fundamental in constructing a <span class="hlt">3</span><span class="hlt">D</span> gravity model. The resulting model provides an accurate image of the salt body extent and its geometry and determines its effect over the surrounding sedimentary deposits.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4517892','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4517892"><span id="translatedtitle">Algebraic Error Based <span class="hlt">Triangulation</span> and Metric of Lines</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Wu, Fuchao; Zhang, Ming; Wang, Guanghui; Hu, Zhanyi</p> <p>2015-01-01</p> <p>Line <span class="hlt">triangulation</span>, a classical geometric problem in computer vision, is to determine the <span class="hlt">3</span><span class="hlt">D</span> coordinates of a line based on its 2D image projections from more than two views of cameras with known projection matrices. Compared to point features, line segments are more robust to matching errors, occlusions, and image uncertainties. In addition to line <span class="hlt">triangulation</span>, a better metric is needed to evaluate <span class="hlt">3</span><span class="hlt">D</span> errors of line <span class="hlt">triangulation</span>. In this paper, the line <span class="hlt">triangulation</span> problem is investigated by using the Lagrange multipliers theory. The main contributions include: (i) Based on the Lagrange multipliers theory, a formula to compute the Plücker correction is provided, and from the formula, a new linear algorithm, LINa, is proposed for line <span class="hlt">triangulation</span>; (ii) two optimal algorithms, OPTa-I and OPTa-II, are proposed by minimizing the algebraic error; and (iii) two metrics on <span class="hlt">3</span><span class="hlt">D</span> line space, the orthogonal metric and the quasi-Riemannian metric, are introduced for the evaluation of line <span class="hlt">triangulations</span>. Extensive experiments on synthetic data and real images are carried out to validate and demonstrate the effectiveness of the proposed algorithms. PMID:26218615</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013CG.....61...94X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013CG.....61...94X"><span id="translatedtitle">Quantifying fluid distribution and phase connectivity with a simple <span class="hlt">3</span><span class="hlt">D</span> cubic pore network model <span class="hlt">constrained</span> by NMR and MICP data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xu, Chicheng; Torres-Verdín, Carlos</p> <p>2013-12-01</p> <p>A computer algorithm is implemented to construct <span class="hlt">3</span><span class="hlt">D</span> cubic pore networks that simultaneously honor nuclear magnetic resonance (NMR) and mercury injection capillary pressure (MICP) measurements on core samples. The algorithm uses discretized pore-body size distributions from NMR and pore-throat size versus incremental pore-volume fraction information from MICP as initial inputs. Both pore-throat radius distribution and body-throat correlation are iteratively refined to match percolation-simulated primary drainage capillary pressure with MICP data. It outputs a pore-throat radius distribution which is not directly measurable with either NMR or MICP. In addition, quasi-static fluid distribution and single-phase connectivity are quantified at each capillary pressure stage. NMR measurements on desaturating core samples are simulated from the quantitative fluid distribution in a gas-displacing-water drainage process and are verified with laboratory measurements. We invoke effective medium theory to quantify the single-phase connectivity in two-phase flow by simulating percolation in equivalent sub-pore-networks that consider the remaining fluid phase as solid cementation. Primary drainage relative permeability curves quantified from fluid distribution and phase connectivity show petrophysical consistency after applying a hydrated-water saturation correction. Core measurements of tight-gas sandstone samples from the Cotton Valley formation, East Texas, are used to verify the new algorithm.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/10165881','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/10165881"><span id="translatedtitle">Refining a <span class="hlt">triangulation</span> of a planar straight-line graph to eliminate large angles</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Mitchell, S.A.</p> <p>1993-05-13</p> <p><span class="hlt">Triangulations</span> without large angles have a number of applications in numerical analysis and computer graphics. In particular, the convergence of a finite element calculation depends on the largest angle of the <span class="hlt">triangulation</span>. Also, the running time of a finite element calculation is dependent on the <span class="hlt">triangulation</span> size, so having a <span class="hlt">triangulation</span> with few Steiner points is also important. Bern, Dobkin and Eppstein pose as an open problem the existence of an algorithm to <span class="hlt">triangulate</span> a planar straight-line graph (PSLG) without large angles using a polynomial number of Steiner points. We solve this problem by showing that any PSLG with {upsilon} vertices can be <span class="hlt">triangulated</span> with no angle larger than 7{pi}/8 by adding O({upsilon}{sup 2}log {upsilon}) Steiner points in O({upsilon}{sup 2} log{sup 2} {upsilon}) time. We first <span class="hlt">triangulate</span> the PSLG with an arbitrary <span class="hlt">constrained</span> <span class="hlt">triangulation</span> and then refine that <span class="hlt">triangulation</span> by adding additional vertices and edges. Some PSLGs require {Omega}({upsilon}{sup 2}) Steiner points in any <span class="hlt">triangulation</span> achieving any largest angle bound less than {pi}. Hence the number of Steiner points added by our algorithm is within a log {upsilon} factor of worst case optimal. We note that our refinement algorithm works on arbitrary <span class="hlt">triangulations</span>: Given any <span class="hlt">triangulation</span>, we show how to refine it so that no angle is larger than 7{pi}/8. Our construction adds O(nm+nplog m) vertices and runs in time O(nm+nplog m) log(m+ p)), where n is the number of edges, m is one plus the number of obtuse angles, and p is one plus the number of holes and interior vertices in the original <span class="hlt">triangulation</span>. A previously considered problem is refining a <span class="hlt">constrained</span> <span class="hlt">triangulation</span> of a simple polygon, where p = 1. For this problem we add O({upsilon}{sup 2}) Steiner points, which is within a constant factor of worst case optimal.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/23483043','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/23483043"><span id="translatedtitle">Blocking Delaunay <span class="hlt">triangulations</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Aichholzer, Oswin; Fabila-Monroy, Ruy; Hackl, Thomas; van Kreveld, Marc; Pilz, Alexander; Ramos, Pedro; Vogtenhuber, Birgit</p> <p>2013-02-01</p> <p>Given a set B of n black points in general position, we say that a set of white points W blocks B if in the Delaunay <span class="hlt">triangulation</span> of [Formula: see text] there is no edge connecting two black points. We give the following bounds for the size of the smallest set W blocking B: (i) [Formula: see text] white points are always sufficient to block a set of n black points, (ii) if B is in convex position, [Formula: see text] white points are always sufficient to block it, and (iii) at least [Formula: see text] white points are always necessary to block a set of n black points. PMID:23483043</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3587385','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3587385"><span id="translatedtitle">Blocking Delaunay <span class="hlt">triangulations</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Aichholzer, Oswin; Fabila-Monroy, Ruy; Hackl, Thomas; van Kreveld, Marc; Pilz, Alexander; Ramos, Pedro; Vogtenhuber, Birgit</p> <p>2013-01-01</p> <p>Given a set B of n black points in general position, we say that a set of white points W blocks B if in the Delaunay <span class="hlt">triangulation</span> of B∪W there is no edge connecting two black points. We give the following bounds for the size of the smallest set W blocking B: (i) 3n/2 white points are always sufficient to block a set of n black points, (ii) if B is in convex position, 5n/4 white points are always sufficient to block it, and (iii) at least n−1 white points are always necessary to block a set of n black points. PMID:23483043</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016Geomo.253..181N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016Geomo.253..181N"><span id="translatedtitle">A method for building <span class="hlt">3</span><span class="hlt">D</span> models of barchan dunes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nai, Yang; Li-lan, Su; Lin, Wan; Jie, Yang; Shi-yi, Chen; Wei-lu, Hu</p> <p>2016-01-01</p> <p>The distributions of barchan dunes are usually represented by digital terrain models (DTMs) overlaid with digital orthophoto maps. Given that most regions with barchan dues have low relief, a <span class="hlt">3</span><span class="hlt">D</span> map obtained from a DTM may ineffectively show the stereoscopic shape of each dune. The method of building <span class="hlt">3</span><span class="hlt">D</span> models of barchan dunes using existing modeling software seldom considers the geographical environment. As a result, barchan dune models are often inconsistent with actual DTMs and incompletely express the morphological characteristics of dunes. Manual construction of barchan dune models is also costly and time consuming. Considering these problems, the morphological characteristics of barchan dunes and the mathematical relationships between the morphological parameters of the dunes, such as length, height, and width, are analyzed in this study. The methods of extracting the morphological feature points of barchan dunes, calculating their morphological parameters and building dune outlines and skeleton lines based on the medial axes, are also presented. The dune outlines, skeleton lines, and part of the medial axes of dunes are used to construct a <span class="hlt">constrained</span> <span class="hlt">triangulated</span> irregular network. C# and ArcEngine are employed to build <span class="hlt">3</span><span class="hlt">D</span> models of barchan dunes automatically. Experimental results of a study conducted in Tengger Desert show that the method can be used to approximate the morphological characteristics of barchan dunes and is less time consuming than manual methods.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20070038219','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20070038219"><span id="translatedtitle">Multi-Sensor <span class="hlt">Triangulation</span> of Multi-Source Spatial Data</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Habib, Ayman; Kim, Chang-Jae; Bang, Ki-In</p> <p>2007-01-01</p> <p>The introduced methodologies are successful in: a) Ising LIDAR features for photogrammetric geo-refererncing; b) Delivering a geo-referenced imagery of the same quality as point-based geo-referencing procedures; c) Taking advantage of the synergistic characteristics of spatial data acquisition systems. The <span class="hlt">triangulation</span> output can be used for the generation of <span class="hlt">3</span>-<span class="hlt">D</span> perspective views.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFM.H41A0835W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFM.H41A0835W"><span id="translatedtitle">Using outcrop observations, <span class="hlt">3</span><span class="hlt">D</span> discrete feature network (DFN) fluid-flow simulations, and subsurface data to <span class="hlt">constrain</span> the impact of normal faults and opening mode fractures on fluid flow in an active asphalt mine</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wilson, C. E.; Aydin, A.; Durlofsky, L.; Karimi-Fard, M.; Brownlow, D. T.</p> <p>2008-12-01</p> <p>An active quarry near Uvalde, TX which mines asphaltic limestone from the Anacacho Formation offers an ideal setting to study fluid-flow in fractured and faulted carbonate rocks. Semi-<span class="hlt">3</span><span class="hlt">D</span> exposures of normal faults and fractures in addition to visual evidence of asphalt concentrations in the quarry help <span class="hlt">constrain</span> relationships between geologic structures and the flow and transport of hydrocarbons. Furthermore, a subsurface dataset which includes thin sections and measured asphalt concentration from the surrounding region provides a basis to estimate asphalt concentrations and <span class="hlt">constrain</span> the depositional architecture of both the previously mined portions of the quarry and the un-mined surrounding rock volume. We characterized a series of normal faults and opening mode fractures at the quarry and documented a correlation between the intensity and distribution of these structures with increased concentrations of asphalt. The three-dimensional depositional architecture of the Anacacho Formation was characterized using the subsurface thin sections. Then outcrop exposures of faults, fractured beds, and stratigraphic contacts were mapped and their three-dimensional positions were recorded with differential gps devices. These two datasets were assimilated and a quarry-scale, geologically realistic, three-dimensional Discrete Feature Network (DFN) which represents the geometries and material properties of the matrix, normal faults, and fractures within the quarry was constructed. We then performed two-point flux, control-volume finite- difference fluid-flow simulations with the DFN to investigate the <span class="hlt">3</span><span class="hlt">D</span> flow and transport of fluids. The results were compared and contrasted with available asphalt concentration estimates from the mine and the aforementioned data from the surrounding drill cores.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25571245','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25571245"><span id="translatedtitle">Segmentation and reconstruction of cerebral vessels from <span class="hlt">3</span><span class="hlt">D</span> rotational angiography for AVM embolization planning.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Li, Fan; Chenoune, Yasmina; Ouenniche, Meriem; Blanc, Raphaël; Petit, Eric</p> <p>2014-01-01</p> <p>Diagnosis and computer-guided therapy of cerebral Arterio-Venous Malformations (AVM) require an accurate understanding of the cerebral vascular network both from structural and biomechanical point of view. We propose to obtain such information by analyzing three Dimensional Rotational Angiography (3DRA) images. In this paper, we describe a two-step process allowing 1) the <span class="hlt">3</span><span class="hlt">D</span> automatic segmentation of cerebral vessels from 3DRA images using a region-growing based algorithm and 2) the reconstruction of the segmented vessels using the <span class="hlt">3</span><span class="hlt">D</span> <span class="hlt">constrained</span> Delaunay <span class="hlt">Triangulation</span> method. The proposed algorithm was successfully applied to reconstruct cerebral blood vessels from ten datasets of 3DRA images. This software allows the neuroradiologist to separately analyze cerebral vessels for pre-operative interventions planning and therapeutic decision making. PMID:25571245</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940028440','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940028440"><span id="translatedtitle">Incremental <span class="hlt">triangulation</span> by way of edge swapping and local optimization</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wiltberger, N. Lyn</p> <p>1994-01-01</p> <p>This document is intended to serve as an installation, usage, and basic theory guide for the two dimensional <span class="hlt">triangulation</span> software 'HARLEY' written for the Silicon Graphics IRIS workstation. This code consists of an incremental <span class="hlt">triangulation</span> algorithm based on point insertion and local edge swapping. Using this basic strategy, several types of <span class="hlt">triangulations</span> can be produced depending on user selected options. For example, local edge swapping criteria can be chosen which minimizes the maximum interior angle (a MinMax <span class="hlt">triangulation</span>) or which maximizes the minimum interior angle (a MaxMin or Delaunay <span class="hlt">triangulation</span>). It should be noted that the MinMax <span class="hlt">triangulation</span> is generally only locally optical (not globally optimal) in this measure. The MaxMin <span class="hlt">triangulation</span>, however, is both locally and globally optical. In addition, Steiner <span class="hlt">triangulations</span> can be constructed by inserting new sites at triangle circumcenters followed by edge swapping based on the MaxMin criteria. Incremental insertion of sites also provides flexibility in choosing cell refinement criteria. A dynamic heap structure has been implemented in the code so that once a refinement measure is specified (i.e., maximum aspect ratio or some measure of a solution gradient for the solution adaptive grid generation) the cell with the largest value of this measure is continually removed from the top of the heap and refined. The heap refinement strategy allows the user to specify either the number of cells desired or refine the mesh until all cell refinement measures satisfy a user specified tolerance level. Since the dynamic heap structure is constantly updated, the algorithm always refines the particular cell in the mesh with the largest refinement criteria value. The code allows the user to: <span class="hlt">triangulate</span> a cloud of prespecified points (sites), <span class="hlt">triangulate</span> a set of prespecified interior points <span class="hlt">constrained</span> by prespecified boundary curve(s), Steiner <span class="hlt">triangulate</span> the interior/exterior of prespecified boundary curve</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008SPIE.6805E..06L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008SPIE.6805E..06L"><span id="translatedtitle">Rapid 360 degree imaging and stitching of <span class="hlt">3</span><span class="hlt">D</span> objects using multiple precision <span class="hlt">3</span><span class="hlt">D</span> cameras</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lu, Thomas; Yin, Stuart; Zhang, Jianzhong; Li, Jiangan; Wu, Frank</p> <p>2008-02-01</p> <p>In this paper, we present the system architecture of a 360 degree view <span class="hlt">3</span><span class="hlt">D</span> imaging system. The system consists of multiple <span class="hlt">3</span><span class="hlt">D</span> sensors synchronized to take <span class="hlt">3</span><span class="hlt">D</span> images around the object. Each <span class="hlt">3</span><span class="hlt">D</span> camera employs a single high-resolution digital camera and a color-coded light projector. The cameras are synchronized to rapidly capture the <span class="hlt">3</span><span class="hlt">D</span> and color information of a static object or a live person. The color encoded structure lighting ensures the precise reconstruction of the depth of the object. A <span class="hlt">3</span><span class="hlt">D</span> imaging system architecture is presented. The architecture employs the displacement of the camera and the projector to <span class="hlt">triangulate</span> the depth information. The <span class="hlt">3</span><span class="hlt">D</span> camera system has achieved high depth resolution down to 0.1mm on a human head sized object and 360 degree imaging capability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013SPIE.8833E..05H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013SPIE.8833E..05H"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> measurement using circular gratings</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Harding, Kevin</p> <p>2013-09-01</p> <p><span class="hlt">3</span><span class="hlt">D</span> measurement using methods of structured light are well known in the industry. Most such systems use some variation of straight lines, either as simple lines or with some form of encoding. This geometry assumes the lines will be projected from one side and viewed from another to generate the profile information. But what about applications where a wide <span class="hlt">triangulation</span> angle may not be practical, particularly at longer standoff distances. This paper explores the use of circular grating patterns projected from a center point to achieve <span class="hlt">3</span><span class="hlt">D</span> information. Originally suggested by John Caulfield around 1990, the method had some interesting potential, particularly if combined with alternate means of measurement from traditional <span class="hlt">triangulation</span> including depth from focus methods. The possible advantages of a central reference point in the projected pattern may offer some different capabilities not as easily attained with a linear grating pattern. This paper will explore the pros and cons of the method and present some examples of possible applications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/20426123','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/20426123"><span id="translatedtitle">Mesh generation from <span class="hlt">3</span><span class="hlt">D</span> multi-material images.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Boltcheva, Dobrina; Yvinec, Mariette; Boissonnat, Jean-Daniel</p> <p>2009-01-01</p> <p>The problem of generating realistic computer models of objects represented by <span class="hlt">3</span><span class="hlt">D</span> segmented images is important in many biomedical applications. Labelled <span class="hlt">3</span><span class="hlt">D</span> images impose particular challenges for meshing algorithms because multi-material junctions form features such as surface pacthes, edges and corners which need to be preserved into the output mesh. In this paper, we propose a feature preserving Delaunay refinement algorithm which can be used to generate high-quality tetrahedral meshes from segmented images. The idea is to explicitly sample corners and edges from the input image and to <span class="hlt">constrain</span> the Delaunay refinement algorithm to preserve these features in addition to the surface patches. Our experimental results on segmented medical images have shown that, within a few seconds, the algorithm outputs a tetrahedral mesh in which each material is represented as a consistent submesh without gaps and overlaps. The optimization property of the Delaunay <span class="hlt">triangulation</span> makes these meshes suitable for the purpose of realistic visualization or finite element simulations. PMID:20426123</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2015EL....10940011K&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2015EL....10940011K&link_type=ABSTRACT"><span id="translatedtitle">Entropy of unimodular lattice <span class="hlt">triangulations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Knauf, Johannes F.; Krüger, Benedikt; Mecke, Klaus</p> <p>2015-02-01</p> <p><span class="hlt">Triangulations</span> are important objects of study in combinatorics, finite element simulations and quantum gravity, where their entropy is crucial for many physical properties. Due to their inherent complex topological structure even the number of possible <span class="hlt">triangulations</span> is unknown for large systems. We present a novel algorithm for an approximate enumeration which is based on calculations of the density of states using the Wang-Landau flat histogram sampling. For <span class="hlt">triangulations</span> on two-dimensional integer lattices we achieve excellent agreement with known exact numbers of small <span class="hlt">triangulations</span> as well as an improvement of analytical calculated asymptotics. The entropy density is C=2.196(3) consistent with rigorous upper and lower bounds. The presented numerical scheme can easily be applied to other counting and optimization problems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013LNP...863...93G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013LNP...863...93G"><span id="translatedtitle">Introduction to Causal Dynamical <span class="hlt">Triangulations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Görlich, Andrzej</p> <p></p> <p>The method of causal dynamical <span class="hlt">triangulations</span> is a non-perturbative and background-independent approach to quantum theory of gravity. In this review we present recent results obtained within the four dimensional model of causal dynamical <span class="hlt">triangulations</span>. We describe the phase structure of the model and demonstrate how a macroscopic four-dimensional de Sitter universe emerges dynamically from the full gravitational path integral. We show how to reconstruct the effective action describing scale factor fluctuations from Monte Carlo data.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li class="active"><span>4</span></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_13");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_4 --> <div id="page_5" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li class="active"><span>5</span></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_13");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="81"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/416823','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/416823"><span id="translatedtitle">Quasi-greedy <span class="hlt">triangulations</span> approximating the minimum weight <span class="hlt">triangulation</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Levcopoulos, C.; Krznaric, D.</p> <p>1996-12-31</p> <p>This paper settles the following two open problems: (1) What is the worst-case approximation ratio between the greedy and the minimum weight <span class="hlt">triangulation</span>? (2) Is there a polynomial time algorithm that always pro- duces a <span class="hlt">triangulation</span> whose length is within a constant factor from the minimum? The answer to the first question is that the known {Omega}({radical}n) lower bound is tight. The second question is answered in the affirmative by using a slight modification of an O(n log n) algorithm for the greedy <span class="hlt">triangulation</span>. We also derive some other interesting results. For example, we show that a constant-factor approximation of the minimum weight convex partition can be obtained within the same time bounds.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013SPIE.8791E..0MG','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013SPIE.8791E..0MG"><span id="translatedtitle">Metrological characterization of <span class="hlt">3</span><span class="hlt">D</span> imaging devices</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Guidi, G.</p> <p>2013-04-01</p> <p>Manufacturers often express the performance of a <span class="hlt">3</span><span class="hlt">D</span> imaging device in various non-uniform ways for the lack of internationally recognized standard requirements for metrological parameters able to identify the capability of capturing a real scene. For this reason several national and international organizations in the last ten years have been developing protocols for verifying such performance. Ranging from VDI/VDE 2634, published by the Association of German Engineers and oriented to the world of mechanical <span class="hlt">3</span><span class="hlt">D</span> measurements (<span class="hlt">triangulation</span>-based devices), to the ASTM technical committee E57, working also on laser systems based on direct range detection (TOF, Phase Shift, FM-CW, flash LADAR), this paper shows the state of the art about the characterization of active range devices, with special emphasis on measurement uncertainty, accuracy and resolution. Most of these protocols are based on special objects whose shape and size are certified with a known level of accuracy. By capturing the <span class="hlt">3</span><span class="hlt">D</span> shape of such objects with a range device, a comparison between the measured points and the theoretical shape they should represent is possible. The actual deviations can be directly analyzed or some derived parameters can be obtained (e.g. angles between planes, distances between barycenters of spheres rigidly connected, frequency domain parameters, etc.). This paper shows theoretical aspects and experimental results of some novel characterization methods applied to different categories of active <span class="hlt">3</span><span class="hlt">D</span> imaging devices based on both principles of <span class="hlt">triangulation</span> and direct range detection.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1236744','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1236744"><span id="translatedtitle">Surface <span class="hlt">Triangulation</span> for CSG in Mercury</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Engel, Daniel; O'Brien, Matthew J.</p> <p>2015-08-26</p> <p>Visualization routines for rendering complicated geometries are very useful for engineers and scientists who are trying to build <span class="hlt">3</span><span class="hlt">D</span> prototypes of their designs. A common way to rapidly add interesting features to a <span class="hlt">3</span><span class="hlt">D</span> model is through the use of a concept called Constructive Solid Geometry. CSG uses compositions of the boolean set operations to manipulate basic geometric primitives to form more complicated objects. The most common boolean operations employed are union, intersection, and subtraction. Most computer-aided design software packages contain some sort of ability visualize CSG. The typical workflow for the user is as follows: The user specifies the individual primitive components, the user arbitrarily combines each of these primitives with boolean operations, the software generates a CSG tree structure which normally stores these solids implicitly with their defining equation, the tree is traversed and a general algorithm is applied to render the appropriate geometry onto the screen. Algorithms for visualizing CSG have been extensively developed for over a decade. Points sampled from the implicit solids are typically used as input by variations of algorithms like marching cubes and point-cloud surface reconstruction. Here, we explain a surface <span class="hlt">triangulation</span> method from the graphics community that is being used for surface visualization in the framework of a Monte-Carlo neutron transport code called Mercury.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007SPIE.6550E..0TB','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007SPIE.6550E..0TB"><span id="translatedtitle">Container integrity verification using laser <span class="hlt">triangulation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Busboom, Axel; Sequeira, Vítor</p> <p>2007-04-01</p> <p>We present a system for verifying the integrity of storage containers using a laser <span class="hlt">triangulation</span> scanner, with applications in nuclear security. Any intrusion into the container shell and subsequent reconstruction of the surface inevitably leaves slight changes to the three-dimensional surface structure which the proposed system can detect. The setup consists of a laser line scanner, mounted on a rotation stage. We propose an auto-calibration procedure for this system which - from several scans of a planar calibration target acquired from different viewpoints - automatically determines the position and orientation of the rotation axis with respect to the scanner coordinate frame. We further present an algorithm for the automatic registration of two <span class="hlt">3</span><span class="hlt">D</span> scans of a cylindrical surface, not requiring any user interaction such as the identification of corresponding point pairs. We show that the algorithm accurately aligns two scans of the same object, acquired from different viewpoints. The accuracy of the overall system is dominated by the measurement uncertainty of the <span class="hlt">3</span><span class="hlt">D</span> scanner; residual errors resulting from the calibration and registration are subordinate. The system can reliably detect changes in the surface shape resulting from tampering.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011ISPAr3816W.483P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011ISPAr3816W.483P"><span id="translatedtitle">Europeana and <span class="hlt">3</span><span class="hlt">D</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pletinckx, D.</p> <p>2011-09-01</p> <p>The current <span class="hlt">3</span><span class="hlt">D</span> hype creates a lot of interest in <span class="hlt">3</span><span class="hlt">D</span>. People go to <span class="hlt">3</span><span class="hlt">D</span> movies, but are we ready to use <span class="hlt">3</span><span class="hlt">D</span> in our homes, in our offices, in our communication? Are we ready to deliver real <span class="hlt">3</span><span class="hlt">D</span> to a general public and use interactive <span class="hlt">3</span><span class="hlt">D</span> in a meaningful way to enjoy, learn, communicate? The CARARE project is realising this for the moment in the domain of monuments and archaeology, so that real <span class="hlt">3</span><span class="hlt">D</span> of archaeological sites and European monuments will be available to the general public by 2012. There are several aspects to this endeavour. First of all is the technical aspect of flawlessly delivering <span class="hlt">3</span><span class="hlt">D</span> content over all platforms and operating systems, without installing software. We have currently a working solution in PDF, but HTML5 will probably be the future. Secondly, there is still little knowledge on how to create <span class="hlt">3</span><span class="hlt">D</span> learning objects, <span class="hlt">3</span><span class="hlt">D</span> tourist information or <span class="hlt">3</span><span class="hlt">D</span> scholarly communication. We are still in a prototype phase when it comes to integrate <span class="hlt">3</span><span class="hlt">D</span> objects in physical or virtual museums. Nevertheless, Europeana has a tremendous potential as a multi-facetted virtual museum. Finally, <span class="hlt">3</span><span class="hlt">D</span> has a large potential to act as a hub of information, linking to related 2D imagery, texts, video, sound. We describe how to create such rich, explorable <span class="hlt">3</span><span class="hlt">D</span> objects that can be used intuitively by the generic Europeana user and what metadata is needed to support the semantic linking.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4464888','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4464888"><span id="translatedtitle">An Effective <span class="hlt">3</span><span class="hlt">D</span> Ear Acquisition System</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Liu, Yahui; Lu, Guangming; Zhang, David</p> <p>2015-01-01</p> <p>The human ear is a new feature in biometrics that has several merits over the more common face, fingerprint and iris biometrics. It can be easily captured from a distance without a fully cooperative subject. Also, the ear has a relatively stable structure that does not change much with the age and facial expressions. In this paper, we present a novel method of <span class="hlt">3</span><span class="hlt">D</span> ear acquisition system by using <span class="hlt">triangulation</span> imaging principle, and the experiment results show that this design is efficient and can be used for ear recognition. PMID:26061553</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26061553','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26061553"><span id="translatedtitle">An Effective <span class="hlt">3</span><span class="hlt">D</span> Ear Acquisition System.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Liu, Yahui; Lu, Guangming; Zhang, David</p> <p>2015-01-01</p> <p>The human ear is a new feature in biometrics that has several merits over the more common face, fingerprint and iris biometrics. It can be easily captured from a distance without a fully cooperative subject. Also, the ear has a relatively stable structure that does not change much with the age and facial expressions. In this paper, we present a novel method of <span class="hlt">3</span><span class="hlt">D</span> ear acquisition system by using <span class="hlt">triangulation</span> imaging principle, and the experiment results show that this design is efficient and can be used for ear recognition. PMID:26061553</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005SPIE.6045E..01F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005SPIE.6045E..01F"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> model reconstruction of underground goaf</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fang, Yuanmin; Zuo, Xiaoqing; Jin, Baoxuan</p> <p>2005-10-01</p> <p>Constructing <span class="hlt">3</span><span class="hlt">D</span> model of underground goaf, we can control the process of mining better and arrange mining work reasonably. However, the shape of goaf and the laneway among goafs are very irregular, which produce great difficulties in data-acquiring and <span class="hlt">3</span><span class="hlt">D</span> model reconstruction. In this paper, we research on the method of data-acquiring and <span class="hlt">3</span><span class="hlt">D</span> model construction of underground goaf, building topological relation among goafs. The main contents are as follows: a) The paper proposed an efficient encoding rule employed to structure the field measurement data. b) A <span class="hlt">3</span><span class="hlt">D</span> model construction method of goaf is put forward, which by means of combining several TIN (<span class="hlt">triangulated</span> irregular network) pieces, and an efficient automatic processing algorithm of boundary of TIN is proposed. c) Topological relation of goaf models is established. TIN object is the basic modeling element of goaf <span class="hlt">3</span><span class="hlt">D</span> model, and the topological relation among goaf is created and maintained by building the topological relation among TIN objects. Based on this, various <span class="hlt">3</span><span class="hlt">D</span> spatial analysis functions can be performed including transect and volume calculation of goaf. A prototype is developed, which can realized the model and algorithm proposed in this paper.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19860009539','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19860009539"><span id="translatedtitle">Some properties of n-dimensional <span class="hlt">triangulations</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lawson, C. L.</p> <p>1985-01-01</p> <p>A number of mathematical results relevant to the problem of constructing a <span class="hlt">triangulation</span>, i.e., a simplicial tessellation, of the convex hull of an arbitrary finite set of points in n-space are described. The principal results achieved are: (1) a set of n+2 points in n-space may be <span class="hlt">triangulated</span> in at most 2 different ways; (2) the sphere test defined in this report selects a preferred one of these two <span class="hlt">triangulations</span>; (3) a set of parameters is defined that permits the characterization and enumeration of all sets of n+2 points in n-space that are significantly different from the point of view of their possible <span class="hlt">triangulation</span>; (4) the local sphere test induces a global sphere test property for a <span class="hlt">triangulation</span>; and (5) a <span class="hlt">triangulation</span> satisfying the global sphere property is dual to the n-dimensional Dirichlet tesselation, i.e., it is a Delaunay <span class="hlt">triangulation</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JHEP...04..140C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JHEP...04..140C"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">d</span>-<span class="hlt">3</span><span class="hlt">d</span> correspondence revisited</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chung, Hee-Joong; Dimofte, Tudor; Gukov, Sergei; Sułkowski, Piotr</p> <p>2016-04-01</p> <p>In fivebrane compactifications on 3-manifolds, we point out the importance of all flat connections in the proper definition of the effective <span class="hlt">3</span><span class="hlt">d</span> {N}=2 theory. The Lagrangians of some theories with the desired properties can be constructed with the help of homological knot invariants that categorify colored Jones polynomials. Higgsing the full <span class="hlt">3</span><span class="hlt">d</span> theories constructed this way recovers theories found previously by Dimofte-Gaiotto-Gukov. We also consider the cutting and gluing of 3-manifolds along smooth boundaries and the role played by all flat connections in this operation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1998JGR...103.1923R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1998JGR...103.1923R"><span id="translatedtitle">Type III radio source located by Ulysses/Wind <span class="hlt">triangulation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Reiner, M. J.; Fainberg, J.; Kaiser, M. L.; Stone, R. G.</p> <p>1998-02-01</p> <p>Radio <span class="hlt">triangulation</span> from the widely separated Ulysses and Wind spacecraft is used to reconstruct the trajectory of a type III radio burst in the <span class="hlt">3</span><span class="hlt">D</span> heliosphere. The derived radio trajectory follows a (Parker) spiral path corresponding to a solar wind speed of about 200 km/s and progresses to the south of the ecliptic plane. These remote radio observations also measure the interplanetary plasma density along the path of the radio source. The derived average density-distance scale is very similar to the previously derived RAE density scale, which was determined in a different way. The results of the radio <span class="hlt">triangulation</span>, combined with a drift rate analysis, give an average electron exciter speed of about 0.3 c. The radio source size and the brightness temperature as viewed from Ulysses and Wind are determined and compared as a function of observing frequency.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2013JPhCS.415a2066M&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2013JPhCS.415a2066M&link_type=ABSTRACT"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> and Education</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Meulien Ohlmann, Odile</p> <p>2013-02-01</p> <p>Today the industry offers a chain of <span class="hlt">3</span><span class="hlt">D</span> products. Learning to "read" and to "create in <span class="hlt">3</span><span class="hlt">D</span>" becomes an issue of education of primary importance. 25 years professional experience in France, the United States and Germany, Odile Meulien set up a personal method of initiation to <span class="hlt">3</span><span class="hlt">D</span> creation that entails the spatial/temporal experience of the holographic visual. She will present some different tools and techniques used for this learning, their advantages and disadvantages, programs and issues of educational policies, constraints and expectations related to the development of new techniques for <span class="hlt">3</span><span class="hlt">D</span> imaging. Although the creation of display holograms is very much reduced compared to the creation of the 90ies, the holographic concept is spreading in all scientific, social, and artistic activities of our present time. She will also raise many questions: What means <span class="hlt">3</span><span class="hlt">D</span>? Is it communication? Is it perception? How the seeing and none seeing is interferes? What else has to be taken in consideration to communicate in <span class="hlt">3</span><span class="hlt">D</span>? How to handle the non visible relations of moving objects with subjects? Does this transform our model of exchange with others? What kind of interaction this has with our everyday life? Then come more practical questions: How to learn creating <span class="hlt">3</span><span class="hlt">D</span> visualization, to learn <span class="hlt">3</span><span class="hlt">D</span> grammar, <span class="hlt">3</span><span class="hlt">D</span> language, <span class="hlt">3</span><span class="hlt">D</span> thinking? What for? At what level? In which matter? for whom?</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013TDR.....4...81T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013TDR.....4...81T"><span id="translatedtitle">Pattern based <span class="hlt">3</span><span class="hlt">D</span> image Steganography</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Thiyagarajan, P.; Natarajan, V.; Aghila, G.; Prasanna Venkatesan, V.; Anitha, R.</p> <p>2013-03-01</p> <p>This paper proposes a new high capacity Steganographic scheme using <span class="hlt">3</span><span class="hlt">D</span> geometric models. The novel algorithm re-<span class="hlt">triangulates</span> a part of a triangle mesh and embeds the secret information into newly added position of triangle meshes. Up to nine bits of secret data can be embedded into vertices of a triangle without causing any changes in the visual quality and the geometric properties of the cover image. Experimental results show that the proposed algorithm is secure, with high capacity and low distortion rate. Our algorithm also resists against uniform affine transformations such as cropping, rotation and scaling. Also, the performance of the method is compared with other existing <span class="hlt">3</span><span class="hlt">D</span> Steganography algorithms. [Figure not available: see fulltext.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=computed+AND+tomography&pg=2&id=EJ663163','ERIC'); return false;" href="http://eric.ed.gov/?q=computed+AND+tomography&pg=2&id=EJ663163"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> Imaging.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Hastings, S. K.</p> <p>2002-01-01</p> <p>Discusses <span class="hlt">3</span> <span class="hlt">D</span> imaging as it relates to digital representations in virtual library collections. Highlights include X-ray computed tomography (X-ray CT); the National Science Foundation (NSF) Digital Library Initiatives; output peripherals; image retrieval systems, including metadata; and applications of <span class="hlt">3</span> <span class="hlt">D</span> imaging for libraries and museums. (LRW)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/21833101','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/21833101"><span id="translatedtitle"><span class="hlt">Triangulation</span> of cubic panorama for view synthesis.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhang, Chunxiao; Zhao, Yan; Wu, Falin</p> <p>2011-08-01</p> <p>An unstructured <span class="hlt">triangulation</span> approach, new to our knowledge, is proposed to apply triangular meshes for representing and rendering a scene on a cubic panorama (CP). It sophisticatedly converts a complicated three-dimensional <span class="hlt">triangulation</span> into a simple three-step <span class="hlt">triangulation</span>. First, a two-dimensional Delaunay <span class="hlt">triangulation</span> is individually carried out on each face. Second, an improved polygonal <span class="hlt">triangulation</span> is implemented in the intermediate regions of each of two faces. Third, a cobweblike <span class="hlt">triangulation</span> is designed for the remaining intermediate regions after unfolding four faces to the top/bottom face. Since the last two steps well solve the boundary problem arising from cube edges, the <span class="hlt">triangulation</span> with irregular-distribution feature points is implemented in a CP as a whole. The triangular meshes can be warped from multiple reference CPs onto an arbitrary viewpoint by face-to-face homography transformations. The experiments indicate that the proposed <span class="hlt">triangulation</span> approach provides a good modeling for the scene with photorealistic rendered CPs. PMID:21833101</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015FoPh..tmp..102C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015FoPh..tmp..102C"><span id="translatedtitle">Making the Case for Causal Dynamical <span class="hlt">Triangulations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cooperman, Joshua H.</p> <p>2015-11-01</p> <p>The aim of the causal dynamical <span class="hlt">triangulations</span> approach is to define nonperturbatively a quantum theory of gravity as the continuum limit of a lattice-regularized model of dynamical geometry. My aim in this paper is to give a concise yet comprehensive, impartial yet personal presentation of the causal dynamical <span class="hlt">triangulations</span> approach.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Lead+AND+Poisoning&id=EJ968446','ERIC'); return false;" href="http://eric.ed.gov/?q=Lead+AND+Poisoning&id=EJ968446"><span id="translatedtitle">Mixed Methods, <span class="hlt">Triangulation</span>, and Causal Explanation</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Howe, Kenneth R.</p> <p>2012-01-01</p> <p>This article distinguishes a disjunctive conception of mixed methods/<span class="hlt">triangulation</span>, which brings different methods to bear on different questions, from a conjunctive conception, which brings different methods to bear on the same question. It then examines a more inclusive, holistic conception of mixed methods/<span class="hlt">triangulation</span> that accommodates…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUFMIN22A..01G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUFMIN22A..01G"><span id="translatedtitle">IGMAS+ A New <span class="hlt">3</span><span class="hlt">D</span> Gravity, FTG and Magnetic Modeling Software</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Goetze, H.; Schmidt, S.; Fichler, C.; Alvers, M. R.</p> <p>2007-12-01</p> <p>Modern geophysical interpretation requires an interdisciplinary approach, particularly when considering the available amount of 'state of the art' information contained in comprehensive data bases. A combination of different geophysical surveys employing seismics, gravity and geoelectrics, together with geological and petrological studies, can provide new insights into the structures and tectonic evolution of the lithosphere and natural deposits. Interdisciplinary interpretation is essential for any numerical modelling of these structures and the processes acting on them. Three-dimensional (<span class="hlt">3</span><span class="hlt">D</span>) interactive modeling with the IGMAS+ software provides means for integrated processing and interpretation of geoid, gravity and magnetic fields and their gradients (full tensor), yielding improved geological interpretation. IGMAS+ is an acronym standing for "Interactive Geophysical Modelling Application System". It bases on the existing software IGMAS (http://www.gravity.uni-kiel.de/igmas), a tool developed during the past twenty years for potential field modelling. The new IGMAS+, however, will comprise the advantages of the "old" IGMAS (e.g. flexible geometry concept and a fast and stable algorithm) with automated interpretation tools and a modern graphical GUI based on leading edge insights from psychological computer graphics research and thus provide optimal man machine communication. IGMAS+ fully three-dimensional models are constructed using <span class="hlt">triangulated</span> polyhedra and/or <span class="hlt">triangulated</span> grids, to which constant density and/or induced and remanent susceptibility are assigned. Interactive modifications of model parameters (geometry, density, susceptibility, magnetization), access to the numerical modeling process, and direct visualization of both calculated and measured fields of gravity and magnetics, enable the interpreter to design the model as realistically as possible. IGMAS+ allows easy integration of <span class="hlt">constraining</span> data into interactive modeling processes</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..12.1306G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..12.1306G"><span id="translatedtitle">IGMAS+ a new <span class="hlt">3</span><span class="hlt">D</span> Gravity, FTG and Magnetic Modeling Software</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Götze, Hans-Jürgen; Schmidt, Sabine; Fichler, Christine; Planka, Christian</p> <p>2010-05-01</p> <p>Modern geophysical interpretation requires an interdisciplinary approach, particularly when considering the available amount of 'state of the art' information contained in comprehensive data bases. A combination of different geophysical surveys employing seismics, gravity and geoelectrics, together with geological and petrological studies, can provide new insights into the structures and tectonic evolution of the lithosphere and natural deposits. Interdisciplinary interpretation is essential for any numerical modelling of these structures and the processes acting on them Three-dimensional (<span class="hlt">3</span><span class="hlt">D</span>) interactive modeling with the IGMAS+ software provides means for integrated processing and interpretation of geoid, gravity and magnetic fields and their gradients (full tensor), yielding improved geological interpretation. IGMAS+ is an acronym standing for "Interactive Geophysical Modelling Application System". It bases on the existing software IGMAS (http://www.gravity.uni-kiel.de/igmas), a tool developed during the past twenty years for potential field modelling. The new IGMAS+, however, will comprise the advantages of the "old" IGMAS (e.g. flexible geometry concept and a fast and stable algorithm) with automated interpretation tools and a modern graphical GUI based on leading edge insights from psychological computer graphics research and thus provide optimal man machine communication. IGMAS+ fully three-dimensional models are constructed using <span class="hlt">triangulated</span> polyhedra and/or <span class="hlt">triangulated</span> grids, to which constant density and/or induced and remanent susceptibility are assigned. Interactive modifications of model parameters (geometry, density, susceptibility, magnetization), access to the numerical modeling process, and direct visualization of both calculated and measured fields of gravity and magnetics, enable the interpreter to design the model as realistically as possible. IGMAS+ allows easy integration of <span class="hlt">constraining</span> data into interactive modeling processes</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6290515','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6290515"><span id="translatedtitle">TRACE <span class="hlt">3</span>-<span class="hlt">D</span> documentation</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Crandall, K.R.</p> <p>1987-08-01</p> <p>TRACE <span class="hlt">3</span>-<span class="hlt">D</span> is an interactive beam-dynamics program that calculates the envelopes of a bunched beam, including linear space-charge forces, through a user-defined transport system. TRACE <span class="hlt">3</span>-<span class="hlt">D</span> provides an immediate graphics display of the envelopes and the phase-space ellipses and allows nine types of beam-matching options. This report describes the beam-dynamics calculations and gives detailed instruction for using the code. Several examples are described in detail.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li class="active"><span>5</span></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_13");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_5 --> <div id="page_6" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active"><span>6</span></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_13");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="101"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..1713235E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..1713235E"><span id="translatedtitle">Influence of different terrain-<span class="hlt">triangulations</span> on a block-based landslide-model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Elsen, Katharina; Tinti, Stefano; Zaniboni, Filippo</p> <p>2015-04-01</p> <p>Influence of different surface-<span class="hlt">triangulations</span> on a block-based landslide-model The present work is investigating the influence of different surface-<span class="hlt">triangulation</span> approaches on the block-based landslide-model developed by Tinti and Bertolucci (2000). For planar (2D) surfaces as well as for objects in the <span class="hlt">3</span><span class="hlt">D</span>-space well-known algorithms like the Delaunay-<span class="hlt">triangulation</span> are available (ensuring also special characteristics of the <span class="hlt">triangulation</span>). This is however not that easy in the 2.5D-case -- needed for example in terrain-<span class="hlt">triangulations</span> -- where a surface is specified by points z=f(x,y). Different methods with (partly) very different results like the 2D-Delaunay <span class="hlt">triangulations</span> (using an orthogonal projection of all points on the (x,y)-plane, implemented e.g. in CGAL), three dimensional topographic terrain representation in an integrated TIN/TEN model (Friso Penninga, 2004) or <span class="hlt">triangulations</span> based on contour lines. Another possibility is to create a regular planar grid (which has the advantage of being stored and accessed in a very simple and fast way) and projecting the points orthogonally on the reconstructed surface. The surface then is represented by those new points. This last method is currently used in our model and shall be compared now to other possible <span class="hlt">triangulations</span>. Simulations are run for simple surfaces (e.g. given by a paraboloid) as well as on more realistic, complex surfaces and evaluated with respect to the arrival times, final velocities and final positions of the sliding mass.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/922825','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/922825"><span id="translatedtitle">4-D XRD for strain in many grains using <span class="hlt">triangulation</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Bale, Hrishikesh A.; Hanan, Jay C.; Tamura, Nobumichi</p> <p>2006-12-31</p> <p>Determination of the strains in a polycrystalline materialusing 4-D XRD reveals sub-grain and grain-to-grain behavior as a functionof stress. Here 4-D XRD involves an experimental procedure usingpolychromatic micro-beam X-radiation (micro-Laue) to characterizepolycrystalline materials in spatial location as well as with increasingstress. The in-situ tensile loading experiment measured strain in a modelaluminum-sapphire metal matrix composite using the Advanced Light Source,Beam-line 7.3.3. Micro-Laue resolves individual grains in thepolycrystalline matrix. Results obtained from a list of grains sorted bycrystallographic orientation depict the strain states within and amongindividual grains. Locating the grain positions in the planeperpendicular to the incident beam is trivial. However, determining theexact location of grains within a <span class="hlt">3</span>-<span class="hlt">D</span> space is challenging. Determiningthe depth of the grains within the matrix (along the beam direction)involved a <span class="hlt">triangulation</span> method tracing individual rays that producespots on the CCD back to the point of origin. <span class="hlt">Triangulation</span> wasexperimentally implemented by simulating a <span class="hlt">3</span>-<span class="hlt">D</span> detector capturingmultiple diffraction images while increasing the camera to sampledistance. Hence by observing the intersection of rays from multiple spotsbelonging to the corresponding grain, depth is calculated. Depthresolution is a function of the number of images collected, grain to beamsize ratio, and the pixel resolution of the CCD. The 4DXRD methodprovides grain morphologies, strain behavior of each grain, andinteractions of the matrix grains with each other and the centrallylocated single crystal fiber.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/23193202','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/23193202"><span id="translatedtitle">Alpha shape and Delaunay <span class="hlt">triangulation</span> in studies of protein-related interactions.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhou, Weiqiang; Yan, Hong</p> <p>2014-01-01</p> <p>In recent years, more <span class="hlt">3</span><span class="hlt">D</span> protein structures have become available, which has made the analysis of large molecular structures much easier. There is a strong demand for geometric models for the study of protein-related interactions. Alpha shape and Delaunay <span class="hlt">triangulation</span> are powerful tools to represent protein structures and have advantages in characterizing the surface curvature and atom contacts. This review presents state-of-the-art applications of alpha shape and Delaunay <span class="hlt">triangulation</span> in the studies on protein-DNA, protein-protein, protein-ligand interactions and protein structure analysis. PMID:23193202</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20070003485&hterms=hamilton-jacobi&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dhamilton-jacobi','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20070003485&hterms=hamilton-jacobi&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dhamilton-jacobi"><span id="translatedtitle">Numerical Schemes for the Hamilton-Jacobi and Level Set Equations on <span class="hlt">Triangulated</span> Domains</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Barth, Timothy J.; Sethian, James A.</p> <p>2006-01-01</p> <p>Borrowing from techniques developed for conservation law equations, we have developed both monotone and higher order accurate numerical schemes which discretize the Hamilton-Jacobi and level set equations on <span class="hlt">triangulated</span> domains. The use of unstructured meshes containing triangles (2D) and tetrahedra (<span class="hlt">3</span><span class="hlt">D</span>) easily accommodates mesh adaptation to resolve disparate level set feature scales with a minimal number of solution unknowns. The minisymposium talk will discuss these algorithmic developments and present sample calculations using our adaptive <span class="hlt">triangulation</span> algorithm applied to various moving interface problems such as etching, deposition, and curvature flow.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2015JPhCS.573a2006O&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2015JPhCS.573a2006O&link_type=ABSTRACT"><span id="translatedtitle">Radiochromic <span class="hlt">3</span><span class="hlt">D</span> Detectors</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Oldham, Mark</p> <p>2015-01-01</p> <p>Radiochromic materials exhibit a colour change when exposed to ionising radiation. Radiochromic film has been used for clinical dosimetry for many years and increasingly so recently, as films of higher sensitivities have become available. The two principle advantages of radiochromic dosimetry include greater tissue equivalence (radiologically) and the lack of requirement for development of the colour change. In a radiochromic material, the colour change arises direct from ionising interactions affecting dye molecules, without requiring any latent chemical, optical or thermal development, with important implications for increased accuracy and convenience. It is only relatively recently however, that <span class="hlt">3</span><span class="hlt">D</span> radiochromic dosimetry has become possible. In this article we review recent developments and the current state-of-the-art of <span class="hlt">3</span><span class="hlt">D</span> radiochromic dosimetry, and the potential for a more comprehensive solution for the verification of complex radiation therapy treatments, and <span class="hlt">3</span><span class="hlt">D</span> dose measurement in general.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JHEP...03..120I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JHEP...03..120I"><span id="translatedtitle">Bootstrapping <span class="hlt">3</span><span class="hlt">D</span> fermions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Iliesiu, Luca; Kos, Filip; Poland, David; Pufu, Silviu S.; Simmons-Duffin, David; Yacoby, Ran</p> <p>2016-03-01</p> <p>We study the conformal bootstrap for a 4-point function of fermions < ψψψψ> in <span class="hlt">3</span><span class="hlt">D</span>. We first introduce an embedding formalism for <span class="hlt">3</span><span class="hlt">D</span> spinors and compute the conformal blocks appearing in fermion 4-point functions. Using these results, we find general bounds on the dimensions of operators appearing in the ψ × ψ OPE, and also on the central charge C T . We observe features in our bounds that coincide with scaling dimensions in the GrossNeveu models at large N . We also speculate that other features could coincide with a fermionic CFT containing no relevant scalar operators.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/10146198','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/10146198"><span id="translatedtitle">Linear-size nonobtuse <span class="hlt">triangulation</span> of polygons</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Bern, M.; Mitchell, S.; Ruppert, J.</p> <p>1994-05-01</p> <p>We give an algorithm for <span class="hlt">triangulating</span> n-vertex polygonal regions (with holes) so that no angle in the final <span class="hlt">triangulation</span> measures more than {pi}/2. The number of triangles in the <span class="hlt">triangulation</span> is only 0(n), improving a previous bound of 0(n{sup 2}), and the worst-case running time is 0(n log{sup 2} n). The basic technique used in the algorithm, recursive subdivision by disks, is new and may have wider application in mesh generation. We also report on an implementation of our algorithm.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005SPIE.6015..467S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005SPIE.6015..467S"><span id="translatedtitle">Vector quantization of <span class="hlt">3</span>-<span class="hlt">D</span> point clouds</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sim, Jae-Young; Kim, Chang-Su; Lee, Sang-Uk</p> <p>2005-10-01</p> <p>A geometry compression algorithm for <span class="hlt">3</span>-<span class="hlt">D</span> QSplat data using vector quantization (VQ) is proposed in this work. The positions of child spheres are transformed to the local coordinate system, which is determined by the parent children relationship. The coordinate transform makes child positions more compactly distributed in <span class="hlt">3</span>-<span class="hlt">D</span> space, facilitating effective quantization. Moreover, we develop a <span class="hlt">constrained</span> encoding method for sphere radii, which guarantees hole-free surface rendering at the decoder side. Simulation results show that the proposed algorithm provides a faithful rendering quality even at low bitrates.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008SPIE.6861E..13I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008SPIE.6861E..13I"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> microscope</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Iizuka, Keigo</p> <p>2008-02-01</p> <p>In order to circumvent the fact that only one observer can view the image from a stereoscopic microscope, an attachment was devised for displaying the <span class="hlt">3</span><span class="hlt">D</span> microscopic image on a large LCD monitor for viewing by multiple observers in real time. The principle of operation, design, fabrication, and performance are presented, along with tolerance measurements relating to the properties of the cellophane half-wave plate used in the design.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013ISPAr.XL1b.157G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013ISPAr.XL1b.157G"><span id="translatedtitle">Uav Photogrammetry: Block <span class="hlt">Triangulation</span> Comparisons</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gini, R.; Pagliari, D.; Passoni, D.; Pinto, L.; Sona, G.; Dosso, P.</p> <p>2013-08-01</p> <p>UAVs systems represent a flexible technology able to collect a big amount of high resolution information, both for metric and interpretation uses. In the frame of experimental tests carried out at Dept. ICA of Politecnico di Milano to validate vector-sensor systems and to assess metric accuracies of images acquired by UAVs, a block of photos taken by a fixed wing system is <span class="hlt">triangulated</span> with several software. The test field is a rural area included in an Italian Park ("Parco Adda Nord"), useful to study flight and imagery performances on buildings, roads, cultivated and uncultivated vegetation. The UAV SenseFly, equipped with a camera Canon Ixus 220HS, flew autonomously over the area at a height of 130 m yielding a block of 49 images divided in 5 strips. Sixteen pre-signalized Ground Control Points, surveyed in the area through GPS (NRTK survey), allowed the referencing of the block and accuracy analyses. Approximate values for exterior orientation parameters (positions and attitudes) were recorded by the flight control system. The block was processed with several software: Erdas-LPS, EyeDEA (Univ. of Parma), Agisoft Photoscan, Pix4UAV, in assisted or automatic way. Results comparisons are given in terms of differences among digital surface models, differences in orientation parameters and accuracies, when available. Moreover, image and ground point coordinates obtained by the various software were independently used as initial values in a comparative adjustment made by scientific in-house software, which can apply constraints to evaluate the effectiveness of different methods of point extraction and accuracies on ground check points.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ISPAr41B3..453A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ISPAr41B3..453A"><span id="translatedtitle">a Modified Method for Image <span class="hlt">Triangulation</span> Using Inclined Angles</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Alsadik, Bashar</p> <p>2016-06-01</p> <p>The ongoing technical improvements in photogrammetry, Geomatics, computer vision (CV), and robotics offer new possibilities for many applications requiring efficient acquisition of three-dimensional data. Image orientation is one of these important techniques in many applications like mapping, precise measurements, <span class="hlt">3</span><span class="hlt">D</span> modeling and navigation. Image orientation comprises three main techniques of resection, intersection (<span class="hlt">triangulation</span>) and relative orientation, which are conventionally solved by collinearity equations or by using projection and fundamental matrices. However, different problems still exist in the state - of -the -art of image orientation because of the nonlinearity and the sensitivity to proper initialization and spatial distribution of the points. In this research, a modified method is presented to solve the <span class="hlt">triangulation</span> problem using inclined angles derived from the measured image coordinates and based on spherical trigonometry rules and vector geometry. The developed procedure shows promising results compared to collinearity approach and to converge to the global minimum even when starting from far approximations. This is based on the strong geometric constraint offered by the inclined angles that are enclosed between the object points and the camera stations. Numerical evaluations with perspective and panoramic images are presented and compared with the conventional solution of collinearity equations. The results show the efficiency of the developed model and the convergence of the solution to global minimum even with improper starting values.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20020083312','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20020083312"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> Audio System</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1992-01-01</p> <p>Ames Research Center research into virtual reality led to the development of the Convolvotron, a high speed digital audio processing system that delivers three-dimensional sound over headphones. It consists of a two-card set designed for use with a personal computer. The Convolvotron's primary application is presentation of <span class="hlt">3</span><span class="hlt">D</span> audio signals over headphones. Four independent sound sources are filtered with large time-varying filters that compensate for motion. The perceived location of the sound remains constant. Possible applications are in air traffic control towers or airplane cockpits, hearing and perception research and virtual reality development.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1998SPIE.3363..423K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1998SPIE.3363..423K"><span id="translatedtitle">Multiviewer <span class="hlt">3</span><span class="hlt">D</span> monitor</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kostrzewski, Andrew A.; Aye, Tin M.; Kim, Dai Hyun; Esterkin, Vladimir; Savant, Gajendra D.</p> <p>1998-09-01</p> <p>Physical Optics Corporation has developed an advanced <span class="hlt">3</span>-<span class="hlt">D</span> virtual reality system for use with simulation tools for training technical and military personnel. This system avoids such drawbacks of other virtual reality (VR) systems as eye fatigue, headaches, and alignment for each viewer, all of which are due to the need to wear special VR goggles. The new system is based on direct viewing of an interactive environment. This innovative holographic multiplexed screen technology makes it unnecessary for the viewer to wear special goggles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013SPIE.8783E..0ZM','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013SPIE.8783E..0ZM"><span id="translatedtitle">Triangular framework mesh generation of <span class="hlt">3</span><span class="hlt">D</span> geological structure</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Meng, Xianhai; Zhou, Kun; Li, Jigang; Yang, Qin</p> <p>2013-03-01</p> <p>The dynamic simulation of oil migration and accumulation is an important issue on the research of petroleum exploration, and it is a numerical simulation process with special requirement on the framework mesh of <span class="hlt">3</span><span class="hlt">D</span> geological models, which means that the mesh should have same geometry and topology relation near the intersected part of geological surfaces. In this paper, basing on the conforming Delaunay <span class="hlt">triangulation</span> algorithm to construct mesh of individual geological stratum or fault, a novel link-Delaunay-<span class="hlt">triangulation</span> method is presented to achieve the geometric and topological consistency in the intersected line between two surfaces, also with the analysis of termination of our algorithm. Finally, some examples of the geological framework mesh are provided and the experimental result proved that the algorithm's effectiveness in engineering practice.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010cosp...38..913N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010cosp...38..913N"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> geometry applied to atmospheric layers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nadjib Kouahla, Mohamed; Moreels, Guy; Faivre, Michael</p> <p></p> <p>Epipolar geometry is an efficient method for generating <span class="hlt">3</span><span class="hlt">D</span> representations of objects. Here we present an original application of this method to the case of atmospheric layers. Two synchronized simultaneous images of the same scene are taken in two sites at a distance D. The 36*36 fields of view are oriented face to face along the same line of sight, but in opposite directions. The elevation angle of the optical axis above the horizon is 17. The observed objects are airglow emissions or cirrus clouds or aircraft trails. In the case of clouds, the shape of the objects is diffuse. To obtain a superposition of the common observed zone, it is necessary to calculate a normalized cross-correlation coefficient (NCC) to identify pairs of matching points in both images. The perspective effect in the rectangular images is inverted to produce a satellite-type view of the atmospheric layer as could be seen from an overlying satellite. We developed a <span class="hlt">triangulation</span> algorithm to retrieve the <span class="hlt">3</span><span class="hlt">D</span> surface of the observed layer. The stereoscopic method was used to retrieve the wavy structure of the OH emissive layer at the altitude of 87 km. The distance between the observing sites was 600 km. Results obtained in Peru from the sites of Cerro Cosmos and Cerro Verde will be presented. We are currently extending the stereoscopic procedure to the study of troposphere cirruses, of natural origin or induced by aircraft engines. In this case, the distance between observation sites is D 60 km.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2994415','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2994415"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> Surgical Simulation</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Cevidanes, Lucia; Tucker, Scott; Styner, Martin; Kim, Hyungmin; Chapuis, Jonas; Reyes, Mauricio; Proffit, William; Turvey, Timothy; Jaskolka, Michael</p> <p>2009-01-01</p> <p>This paper discusses the development of methods for computer-aided jaw surgery. Computer-aided jaw surgery allows us to incorporate the high level of precision necessary for transferring virtual plans into the operating room. We also present a complete computer-aided surgery (CAS) system developed in close collaboration with surgeons. Surgery planning and simulation include construction of <span class="hlt">3</span><span class="hlt">D</span> surface models from Cone-beam CT (CBCT), dynamic cephalometry, semi-automatic mirroring, interactive cutting of bone and bony segment repositioning. A virtual setup can be used to manufacture positioning splints for intra-operative guidance. The system provides further intra-operative assistance with the help of a computer display showing jaw positions and <span class="hlt">3</span><span class="hlt">D</span> positioning guides updated in real-time during the surgical procedure. The CAS system aids in dealing with complex cases with benefits for the patient, with surgical practice, and for orthodontic finishing. Advanced software tools for diagnosis and treatment planning allow preparation of detailed operative plans, osteotomy repositioning, bone reconstructions, surgical resident training and assessing the difficulties of the surgical procedures prior to the surgery. CAS has the potential to make the elaboration of the surgical plan a more flexible process, increase the level of detail and accuracy of the plan, yield higher operative precision and control, and enhance documentation of cases. Supported by NIDCR DE017727, and DE018962 PMID:20816308</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4985141','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4985141"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> Printed Multimaterial Microfluidic Valve</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Patrick, William G.; Sharma, Sunanda; Kong, David S.; Oxman, Neri</p> <p>2016-01-01</p> <p>We present a novel <span class="hlt">3</span><span class="hlt">D</span> printed multimaterial microfluidic proportional valve. The microfluidic valve is a fundamental primitive that enables the development of programmable, automated devices for controlling fluids in a precise manner. We discuss valve characterization results, as well as exploratory design variations in channel width, membrane thickness, and membrane stiffness. Compared to previous single material <span class="hlt">3</span><span class="hlt">D</span> printed valves that are stiff, these printed valves <span class="hlt">constrain</span> fluidic deformation spatially, through combinations of stiff and flexible materials, to enable intricate geometries in an actuated, functionally graded device. Research presented marks a shift towards <span class="hlt">3</span><span class="hlt">D</span> printing multi-property programmable fluidic devices in a single step, in which integrated multimaterial valves can be used to control complex fluidic reactions for a variety of applications, including DNA assembly and analysis, continuous sampling and sensing, and soft robotics. PMID:27525809</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27525809','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27525809"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> Printed Multimaterial Microfluidic Valve.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Keating, Steven J; Gariboldi, Maria Isabella; Patrick, William G; Sharma, Sunanda; Kong, David S; Oxman, Neri</p> <p>2016-01-01</p> <p>We present a novel <span class="hlt">3</span><span class="hlt">D</span> printed multimaterial microfluidic proportional valve. The microfluidic valve is a fundamental primitive that enables the development of programmable, automated devices for controlling fluids in a precise manner. We discuss valve characterization results, as well as exploratory design variations in channel width, membrane thickness, and membrane stiffness. Compared to previous single material <span class="hlt">3</span><span class="hlt">D</span> printed valves that are stiff, these printed valves <span class="hlt">constrain</span> fluidic deformation spatially, through combinations of stiff and flexible materials, to enable intricate geometries in an actuated, functionally graded device. Research presented marks a shift towards <span class="hlt">3</span><span class="hlt">D</span> printing multi-property programmable fluidic devices in a single step, in which integrated multimaterial valves can be used to control complex fluidic reactions for a variety of applications, including DNA assembly and analysis, continuous sampling and sensing, and soft robotics. PMID:27525809</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1990SPIE.1194..186B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1990SPIE.1194..186B"><span id="translatedtitle"><span class="hlt">Triangulation</span>-Based Camera Calibration For Machine Vision Systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bachnak, Rafic A.; Celenk, Mehmet</p> <p>1990-04-01</p> <p>This paper describes a camera calibration procedure for stereo-based machine vision systems. The method is based on geometric <span class="hlt">triangulation</span> using only a single image of three distinctive points. Both the intrinsic and extrinsic parameters of the system are determined. The procedure is performed only once at the initial set-up using a simple camera model. The effective focal length is extended in such a way that a linear transformation exists between the camera image plane and the output digital image. Only three world points are needed to find the extended focal length and the transformation matrix elements that relates the camera position and orientation to a real world coordinate system. The parameters of the system are computed by solving a set of linear equations. Experimental results show that the method, when used in a stereo system developed in this research, produces reasonably accurate <span class="hlt">3</span>-<span class="hlt">D</span> measurements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008JCST....2..655Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008JCST....2..655Y"><span id="translatedtitle">A Software System for Filling Complex Holes in <span class="hlt">3</span><span class="hlt">D</span> Meshes by Flexible Interacting Particles</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yamazaki, Daisuke; Savchenko, Vladimir</p> <p></p> <p><span class="hlt">3</span><span class="hlt">D</span> meshes generated by acquisition devices such as laser range scanners often contain holes due to occlusion, etc. In practice, these holes are extremely geometrically and topologically complex. We propose a heuristic hole filling technique using particle systems to fill complex holes with arbitrary topology in <span class="hlt">3</span><span class="hlt">D</span> meshes. Our approach includes the following steps: hole identification, base surface creation, particle distribution, <span class="hlt">triangulation</span>, and mesh refinement. We demonstrate the functionality of the proposed surface retouching system on synthetic and real data.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active"><span>6</span></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_13");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_6 --> <div id="page_7" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_13");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="121"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=PIA05562&hterms=bonneville&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dbonneville','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=PIA05562&hterms=bonneville&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dbonneville"><span id="translatedtitle">'Bonneville' in <span class="hlt">3</span>-<span class="hlt">D</span>!</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2004-01-01</p> <p>The Mars Exploration Rover Spirit took this <span class="hlt">3</span>-<span class="hlt">D</span> navigation camera mosaic of the crater called 'Bonneville' after driving approximately 13 meters (42.7 feet) to get a better vantage point. Spirit's current position is close enough to the edge to see the interior of the crater, but high enough and far enough back to get a view of all of the walls. Because scientists and rover controllers are so pleased with this location, they will stay here for at least two more martian days, or sols, to take high resolution panoramic camera images of 'Bonneville' in its entirety. Just above the far crater rim, on the left side, is the rover's heatshield, which is visible as a tiny reflective speck.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/5232433','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/5232433"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> field harmonics</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Caspi, S.; Helm, M.; Laslett, L.J.</p> <p>1991-03-30</p> <p>We have developed an harmonic representation for the three dimensional field components within the windings of accelerator magnets. The form by which the field is presented is suitable for interfacing with other codes that make use of the <span class="hlt">3</span><span class="hlt">D</span> field components (particle tracking and stability). The field components can be calculated with high precision and reduced cup time at any location (r,{theta},z) inside the magnet bore. The same conductor geometry which is used to simulate line currents is also used in CAD with modifications more readily available. It is our hope that the format used here for magnetic fields can be used not only as a means of delivering fields but also as a way by which beam dynamics can suggest correction to the conductor geometry. 5 refs., 70 figs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010OptCo.283.4430G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010OptCo.283.4430G"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> polarimetric purity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gil, José J.; San José, Ignacio</p> <p>2010-11-01</p> <p>From our previous definition of the indices of polarimetric purity for <span class="hlt">3</span><span class="hlt">D</span> light beams [J.J. Gil, J.M. Correas, P.A. Melero and C. Ferreira, Monogr. Semin. Mat. G. de Galdeano 31, 161 (2004)], an analysis of their geometric and physical interpretation is presented. It is found that, in agreement with previous results, the first parameter is a measure of the degree of polarization, whereas the second parameter (called the degree of directionality) is a measure of the mean angular aperture of the direction of propagation of the corresponding light beam. This pair of invariant, non-dimensional, indices of polarimetric purity contains complete information about the polarimetric purity of a light beam. The overall degree of polarimetric purity is obtained as a weighted quadratic average of the degree of polarization and the degree of directionality.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001SPIE.4298....1H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001SPIE.4298....1H"><span id="translatedtitle">CMOS array of photodiodes with electronic processing for <span class="hlt">3</span><span class="hlt">D</span> optical reconstruction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hornero, Gemma; Montane, Enric; Chapinal, Genis; Moreno, Mauricio; Herms, Atila</p> <p>2001-04-01</p> <p>It is well known that laser time-of-flight (TOF) and optical <span class="hlt">triangulation</span> are the most useful optical techniques for distance measurements. The first one is more suitable for large distances, since for short range of distances high modulation frequencies of laser diodes (©200-500MHz) are needed. For these ranges, optical <span class="hlt">triangulation</span> is simpler, as it is only necessary to read the projection of the laser point over a linear optical sensor without any laser modulation. Laser <span class="hlt">triangulation</span> is based on the rotation of the object. This motion shifts the projected point over the linear sensor, resulting on <span class="hlt">3</span><span class="hlt">D</span> information, by means of the whole readout of the linear sensor in each angle position. On the other hand, a hybrid method of <span class="hlt">triangulation</span> and TOF can be implemented. In this case, a synchronized scanning of a laser beam over the object results in different arrival times of light to each pixel. The <span class="hlt">3</span><span class="hlt">D</span> information is carried by these delays. Only a single readout of the linear sensor is needed. In this work we present the design of two different linear arrays of photodiodes in CMOS technology, the first one based on the Optical <span class="hlt">triangulation</span> measurement and the second one based in this hybrid method (TFO). In contrast to PSD (Position Sensitive Device) and CCDs, CMOS technology can include, on the same chip, photodiodes, control and processing electronics, that in the other cases should be implemented with external microcontrollers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=PIA00680&hterms=Pumpkin&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DPumpkin','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=PIA00680&hterms=Pumpkin&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DPumpkin"><span id="translatedtitle">Prominent rocks - <span class="hlt">3</span><span class="hlt">D</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1997-01-01</p> <p>Many prominent rocks near the Sagan Memorial Station are featured in this image, taken in stereo by the Imager for Mars Pathfinder (IMP) on Sol 3. <span class="hlt">3</span><span class="hlt">D</span> glasses are necessary to identify surface detail. Wedge is at lower left; Shark, Half-Dome, and Pumpkin are at center. Flat Top, about four inches high, is at lower right. The horizon in the distance is one to two kilometers away.<p/>Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is an operating division of the California Institute of Technology (Caltech). The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.<p/>Click below to see the left and right views individually. [figure removed for brevity, see original site] Left [figure removed for brevity, see original site] Right</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=PIA06786&hterms=rodent&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Drodent','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=PIA06786&hterms=rodent&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Drodent"><span id="translatedtitle">'Diamond' in <span class="hlt">3</span>-<span class="hlt">D</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2004-01-01</p> <p><p/> This <span class="hlt">3</span>-<span class="hlt">D</span>, microscopic imager mosaic of a target area on a rock called 'Diamond Jenness' was taken after NASA's Mars Exploration Rover Opportunity ground into the surface with its rock abrasion tool for a second time. <p/> Opportunity has bored nearly a dozen holes into the inner walls of 'Endurance Crater.' On sols 177 and 178 (July 23 and July 24, 2004), the rover worked double-duty on Diamond Jenness. Surface debris and the bumpy shape of the rock resulted in a shallow and irregular hole, only about 2 millimeters (0.08 inch) deep. The final depth was not enough to remove all the bumps and leave a neat hole with a smooth floor. This extremely shallow depression was then examined by the rover's alpha particle X-ray spectrometer. <p/> On Sol 178, Opportunity's 'robotic rodent' dined on Diamond Jenness once again, grinding almost an additional 5 millimeters (about 0.2 inch). The rover then applied its Moessbauer spectrometer to the deepened hole. This double dose of Diamond Jenness enabled the science team to examine the rock at varying layers. Results from those grindings are currently being analyzed. <p/> The image mosaic is about 6 centimeters (2.4 inches) across.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014OptLE..54..175R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014OptLE..54..175R"><span id="translatedtitle">Optical monitoring of scoliosis by <span class="hlt">3</span><span class="hlt">D</span> medical laser scanner</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rodríguez-Quiñonez, Julio C.; Sergiyenko, Oleg Yu.; Preciado, Luis C. Basaca; Tyrsa, Vera V.; Gurko, Alexander G.; Podrygalo, Mikhail A.; Lopez, Moises Rivas; Balbuena, Daniel Hernandez</p> <p>2014-03-01</p> <p>Three dimensional recording of the human body surface or anatomical areas have gained importance in many medical applications. In this paper, our <span class="hlt">3</span><span class="hlt">D</span> Medical Laser Scanner is presented. It is based on the novel principle of dynamic <span class="hlt">triangulation</span>. We analyze the method of operation, medical applications, orthopedically diseases as Scoliosis and the most common types of skin to employ the system the most proper way. It is analyzed a group of medical problems related to the application of optical scanning in optimal way. Finally, experiments are conducted to verify the performance of the proposed system and its method uncertainty.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1990SPIE.1267..158B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1990SPIE.1267..158B"><span id="translatedtitle"><span class="hlt">Triangulation</span> technique in optical fiber sensing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brenci, Massimo; Mencaglia, Andrea A.; Mignani, Anna G.</p> <p>1990-08-01</p> <p>Optical <span class="hlt">triangulation</span> is a very well-known classical technique which can be advantageously performed by optical fibers, taking profit from their geometrical versatility, intrinsic safety and good transmission properties. The exploitation of different optical architectures provides spatial information over single or multiple sensing zones, so that a wide class of intensity-modulated optical fiber sensors can be achieved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JSP...163..514K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JSP...163..514K"><span id="translatedtitle">Spectral Properties of Unimodular Lattice <span class="hlt">Triangulations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Krüger, Benedikt; Schmidt, Ella M.; Mecke, Klaus</p> <p>2016-05-01</p> <p>Random unimodular lattice <span class="hlt">triangulations</span> have been recently used as an embedded random graph model, which exhibit a crossover behavior between an ordered, large-world and a disordered, small-world behavior. Using the ergodic Pachner flips that transform such <span class="hlt">triangulations</span> into another and an energy functional that corresponds to the degree distribution variance, Markov chain Monte Carlo simulations can be applied to study these graphs. Here, we consider the spectra of the adjacency and the Laplacian matrix as well as the algebraic connectivity and the spectral radius. Power law dependencies on the system size can clearly be identified and compared to analytical solutions for periodic ground states. For random <span class="hlt">triangulations</span> we find a qualitative agreement of the spectral properties with well-known random graph models. In the microcanonical ensemble analytical approximations agree with numerical simulations. In the canonical ensemble a crossover behavior can be found for the algebraic connectivity and the spectral radius, thus combining large-world and small-world behavior in one model. The considered spectral properties can be applied to transport problems on <span class="hlt">triangulation</span> graphs and the crossover behavior allows a tuning of important transport quantities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..1410902K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..1410902K"><span id="translatedtitle">Towards "realistic" fault zones in a <span class="hlt">3</span><span class="hlt">D</span> structure model of the Thuringian Basin, Germany</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kley, J.; Malz, A.; Donndorf, S.; Fischer, T.; Zehner, B.</p> <p>2012-04-01</p> <p><span class="hlt">3</span><span class="hlt">D</span> computer models of geological architecture are evolving into a standard tool for visualization and analysis. Such models typically comprise the bounding surfaces of stratigraphic layers and faults. Faults affect the continuity of aquifers and can themselves act as fluid conduits or barriers. This is one reason why a "realistic" representation of faults in <span class="hlt">3</span><span class="hlt">D</span> models is desirable. Still so, many existing models treat faults in a simplistic fashion, e.g. as vertical downward projections of fault traces observed at the surface. Besides being geologically and mechanically unreasonable, this also causes technical difficulties in the modelling workflow. Most natural faults are inclined and may change dips according to rock type or flatten into mechanically weak layers. Boreholes located close to a fault can therefore cross it at depth, resulting in stratigraphic control points allocated to the wrong block. Also, faults tend to split up into several branches, forming fault zones. Obtaining a more accurate representation of faults and fault zones is therefore challenging. We present work-in-progress from the Thuringian Basin in central Germany. The fault zone geometries are never fully <span class="hlt">constrained</span> by data and must be extrapolated to depth. We use balancing of serial, parallel cross-sections to <span class="hlt">constrain</span> subsurface extrapolations. The structure sections are checked for consistency by restoring them to an undeformed state. If this is possible without producing gaps or overlaps, the interpretation is considered valid (but not unique) for a single cross-section. Additional constraints are provided by comparison of adjacent cross-sections. Structures should change continuously from one section to another. Also, from the deformed and restored cross-sections we can measure the strain incurred during deformation. Strain should be compatible among the cross-sections: If at all, it should vary smoothly and systematically along a given fault zone. The stratigraphic contacts and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19920001696','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19920001696"><span id="translatedtitle"><span class="hlt">Triangulation</span> using synthetic aperture radar images</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wu, Sherman S. C.; Howington-Kraus, Annie E.</p> <p>1991-01-01</p> <p>For the extraction of topographic information about Venus from stereoradar images obtained from the Magellan Mission, a Synthetic Aperture Radar (SAR) compilation system was developed on analytical stereoplotters. The system software was extensively tested by using stereoradar images from various spacecraft and airborne radar systems, including Seasat, SIR-B, ERIM XCL, and STAR-1. Stereomodeling from radar images was proven feasible, and development is on a correct approach. During testing, the software was enhanced and modified to obtain more flexibility and better precision. <span class="hlt">Triangulation</span> software for establishing control points by using SAR images was also developed through a joint effort with the Defense Mapping Agency. The SAR <span class="hlt">triangulation</span> system comprises four main programs, TRIDATA, MODDATA, TRISAR, and SHEAR. The first two programs are used to sort and update the data; the third program, the main one, performs iterative statistical adjustment; and the fourth program analyzes the results. Also, input are flight data and data from the Global Positioning System and Inertial System (navigation information). The SAR <span class="hlt">triangulation</span> system was tested with six strips of STAR-1 radar images on a VAX-750 computer. Each strip contains images of 10 minutes flight time (equivalent to a ground distance of 73.5 km); the images cover a ground width of 22.5 km. All images were collected from the same side. With an input of 44 primary control points, 441 ground control points were produced. The adjustment process converged after eight iterations. With a 6-m/pixel resolution of the radar images, the <span class="hlt">triangulation</span> adjustment has an average standard elevation error of 81 m. Development of Magellan radargrammetry will be continued to convert both SAR compilation and <span class="hlt">triangulation</span> systems into digital form.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JPRS..101..233R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JPRS..101..233R"><span id="translatedtitle">Aerial multi-camera systems: Accuracy and block <span class="hlt">triangulation</span> issues</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rupnik, Ewelina; Nex, Francesco; Toschi, Isabella; Remondino, Fabio</p> <p>2015-03-01</p> <p>Oblique photography has reached its maturity and has now been adopted for several applications. The number and variety of multi-camera oblique platforms available on the market is continuously growing. So far, few attempts have been made to study the influence of the additional cameras on the behaviour of the image block and comprehensive revisions to existing flight patterns are yet to be formulated. This paper looks into the precision and accuracy of <span class="hlt">3</span><span class="hlt">D</span> points <span class="hlt">triangulated</span> from diverse multi-camera oblique platforms. Its coverage is divided into simulated and real case studies. Within the simulations, different imaging platform parameters and flight patterns are varied, reflecting both current market offerings and common flight practices. Attention is paid to the aspect of completeness in terms of dense matching algorithms and <span class="hlt">3</span><span class="hlt">D</span> city modelling - the most promising application of such systems. The experimental part demonstrates the behaviour of two oblique imaging platforms in real-world conditions. A number of Ground Control Point (GCP) configurations are adopted in order to point out the sensitivity of tested imaging networks and arising block deformations. To stress the contribution of slanted views, all scenarios are compared against a scenario in which exclusively nadir images are used for evaluation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1988SPIE..959..225B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1988SPIE..959..225B"><span id="translatedtitle">Practical Considerations For A Design Of A High Precision <span class="hlt">3</span>-<span class="hlt">D</span> Laser Scanner System</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Blais, Francois; Rioux, Marc; Beraldin, J.-Angelo</p> <p>1988-11-01</p> <p>The Laboratory for Intelligent Systems of the Division of Electrical Engineering of the National Research Council of Canada is intensively involved in the development of laser-based three-dimensional vision systems and their applications. Two basic systems have been invented. One, based on a double aperture mask in front of a CCD camera, has been developed for robotic applications and control. The other technique is based on an auto-synchronized scanning principle to provide accurate, fast, and reliable <span class="hlt">3</span>-<span class="hlt">D</span> coordinates. Using the latter method, several prototypes have been developed for the acquisition of <span class="hlt">3</span>-<span class="hlt">D</span> data of objects and for inspection. This paper will describe some practical considerations for the design and implementation of <span class="hlt">triangulation</span>-based <span class="hlt">3</span>-<span class="hlt">D</span> range sensors with emphasis on the latter <span class="hlt">triangulation</span> technique. Some applications and results will be presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1997PhDT........88E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1997PhDT........88E"><span id="translatedtitle">A comprehensive study on GPS-assisted aerial <span class="hlt">triangulation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ebadi, Hamid</p> <p></p> <p>Aerial <span class="hlt">Triangulation</span> (AT) has been used for mapping purposes for a long time to provide <span class="hlt">3</span><span class="hlt">D</span> coordinates of object points on the ground. This technique uses series of overlapping photographs, and some control points, in order to establish the relationship between the image coordinate system and object coordinate system. In the process of bundle block adjustment, image coordinate observations and coordinates of the ground control points are simultaneously adjusted and the exterior orientation parameters, as well as the ground coordinates of all tie and pass points, are estimated. One of the biggest challenges in AT is to reduce the number of control points. One effective way is to directly measure the exterior orientation parameters of the camera at the time of exposure. Airborne kinematic GPS (Global Positioning System) provides a means of determining the position of the aerial camera at each instant of exposure. The combined GPS-photogrammetric block adjustment takes advantage of weighted GPS observations, which significantly reduces the number of ground control points needed in a conventional block adjustment. A comprehensive software package, GAP (General Adjustment Program), was developed in this research to effectively integrate and adjust GPS, geodetic, and photogrammetric observations. Optimization of the GPS-photogrammetric bundle block adjustments for both simulated large scale mapping and real medium scale mapping was carried out. Aspects of reliability, and precision, as well as practical considerations, for an airborne GPS-photogrammetry system were also investigated. GPS coordinates of the camera exposure stations do not permit recovery of the roll angle of the aircraft in a GPS single strip <span class="hlt">triangulation</span>. Therefore, ground control points are still required in addition to the GPS coordinates of exposure stations to overcome this problem, and to eliminate singularity of the normal matrix in the least squares adjustment. A new technique for GPS single</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015APS..APR.X7006G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015APS..APR.X7006G"><span id="translatedtitle">The Newtonian approximation in Causal Dynamical <span class="hlt">Triangulations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Getchell, Adam</p> <p>2015-04-01</p> <p>I review how to derive Newton's law of universal gravitation from the Weyl strut between two Chazy-Curzon particles. I also briefly review Causal Dynamical <span class="hlt">Triangulations</span> (CDT), a method for evaluating the path integral from canonical quantum gravity using Regge calculus and restrictions of the class of simplicial manifolds evaluated to those with a defined time foliation, thus enforcing a causal structure. I then discuss how to apply this approach to Causal Dynamical <span class="hlt">Triangulations</span>, in particular modifying the algorithm to keep two simplicial submanifolds with curvature (i.e. mass) a fixed distance from each other, modulo regularized deviations and across all time slices. I then discuss how to determine if CDT produces an equivalent Weyl strut, which can then be used to obtain the Newtonian limit. I wrap up with a brief discussion of computational methods and code development.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012NuPhB.858..267A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012NuPhB.858..267A"><span id="translatedtitle">Roaming moduli space using dynamical <span class="hlt">triangulations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ambjørn, J.; Barkley, J.; Budd, T. G.</p> <p>2012-05-01</p> <p>In critical as well as in non-critical string theory the partition function reduces to an integral over moduli space after integration over matter fields. For non-critical string theory this moduli integrand is known for genus one surfaces. The formalism of dynamical <span class="hlt">triangulations</span> provides us with a regularization of non-critical string theory. We show how to assign in a simple and geometrical way a moduli parameter to each <span class="hlt">triangulation</span>. After integrating over possible matter fields we can thus construct the moduli integrand. We show numerically for c=0 and c=-2 non-critical strings that the moduli integrand converges to the known continuum expression when the number of triangles goes to infinity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..1712313C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..1712313C"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> modelling in salt tectonic context: the Crocodile minibasin in Sivas (Turkey)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Collon, Pauline; Pichat, Alexandre; Kergaravat, Charlie; Botella, Arnaud; Caumon, Guillaume; Favreau, Océane; Fuss, Gaétan; Godefroy, Gabriel; Lerat, Marine; Mazuyer, Antoine; Parquer, Marion; Charreau, Julien; Callot, Jean-Paul; Ringenbach, Jean-Claude</p> <p>2015-04-01</p> <p>Impermeable, with a low density and acting as a viscous fluid at the geological time scale, salt plays a unique tectonic role favouring hydrocarbon trap formations. Halokinetic structures are various and difficult to image with classic seismic techniques. Thus, outcrop analogues are precious and sought after. Since the re-interpretation in September 2011 of its evaporite deposits, the Oligo-Miocene basin of Sivas (Turkey) is a new choice analogue for the study of salt tectonic with outstanding outcrops reflecting the variety of salt related structures: minibasins, diapirs, welds... While studying these structures requires an important field work, building <span class="hlt">3</span><span class="hlt">D</span> models becomes an interesting way to better help understanding the three-dimensional organisation and to further perform numerical simulations (e.g., restoration, potential field measurement campaign simulation). The complex geometries observed in salt tectonic context make these <span class="hlt">3</span><span class="hlt">D</span> geological models particularly challenging to build, especially when only outcrops data are available. We focus on the Crocodile minibasin (Sivas) and present a modelling strategy using a subtle combination of recently developed techniques. Available data are: a Digital Elevation Model, satellite images and associated interpreted bedding traces on topography, orientation measurements of the strata and a conceptual interpretation. Located on an ancient salt extrusion, this minibasin is filled with lacustrine and sabkha sediments. It is interpreted with a closed synclinal structure on North. On its southern part, a central diapir has risen up, separating two tightened synclinals. The salt surface is modelled first as a <span class="hlt">triangulated</span> surface using a classical explicit surface patch construction method and a manual post-process mesh improvement. Then, the minibasin sediments are modelled with an implicit approach that considers interfaces as equipotentials of a <span class="hlt">3</span><span class="hlt">D</span> scalar field. This requires to build a volumetric mesh conformable to the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011tdsa.book.....M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011tdsa.book.....M"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> Spectroscopy in Astronomy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mediavilla, Evencio; Arribas, Santiago; Roth, Martin; Cepa-Nogué, Jordi; Sánchez, Francisco</p> <p>2011-09-01</p> <p>Preface; Acknowledgements; 1. Introductory review and technical approaches Martin M. Roth; 2. Observational procedures and data reduction James E. H. Turner; 3. <span class="hlt">3</span><span class="hlt">D</span> Spectroscopy instrumentation M. A. Bershady; 4. Analysis of <span class="hlt">3</span><span class="hlt">D</span> data Pierre Ferruit; 5. Science motivation for IFS and galactic studies F. Eisenhauer; 6. Extragalactic studies and future IFS science Luis Colina; 7. Tutorials: how to handle <span class="hlt">3</span><span class="hlt">D</span> spectroscopy data Sebastian F. Sánchez, Begona García-Lorenzo and Arlette Pécontal-Rousset.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.usgs.gov/fs/2016/3022/fs20163022.pdf','USGSPUBS'); return false;" href="http://pubs.usgs.gov/fs/2016/3022/fs20163022.pdf"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> Elevation Program—Virtual USA in <span class="hlt">3</span><span class="hlt">D</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Lukas, Vicki; Stoker, J.M.</p> <p>2016-01-01</p> <p>The U.S. Geological Survey (USGS) <span class="hlt">3</span><span class="hlt">D</span> Elevation Program (3DEP) uses a laser system called ‘lidar’ (light detection and ranging) to create a virtual reality map of the Nation that is very accurate. <span class="hlt">3</span><span class="hlt">D</span> maps have many uses with new uses being discovered all the time.  </p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24734998','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24734998"><span id="translatedtitle">Extending particle tracking capability with Delaunay <span class="hlt">triangulation</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chen, Kejia; Anthony, Stephen M; Granick, Steve</p> <p>2014-04-29</p> <p>Particle tracking, the analysis of individual moving elements in time series of microscopic images, enables burgeoning new applications, but there is need to better resolve conformation and dynamics. Here we describe the advantages of Delaunay <span class="hlt">triangulation</span> to extend the capabilities of particle tracking in three areas: (1) discriminating irregularly shaped objects, which allows one to track items other than point features; (2) combining time and space to better connect missing frames in trajectories; and (3) identifying shape backbone. To demonstrate the method, specific examples are given, involving analyzing the time-dependent molecular conformations of actin filaments and λ-DNA. The main limitation of this method, shared by all other clustering techniques, is the difficulty to separate objects when they are very close. This can be mitigated by inspecting locally to remove edges that are longer than their neighbors and also edges that link two objects, using methods described here, so that the combination of Delaunay <span class="hlt">triangulation</span> with edge removal can be robustly applied to processing large data sets. As common software packages, both commercial and open source, can construct Delaunay <span class="hlt">triangulation</span> on command, the methods described in this paper are both computationally efficient and easy to implement. PMID:24734998</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_13");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_7 --> <div id="page_8" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_13");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="141"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010JGRA..115.0E12S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010JGRA..115.0E12S"><span id="translatedtitle">Sprite initiation altitude measured by <span class="hlt">triangulation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Stenbaek-Nielsen, H. C.; Haaland, R.; McHarg, M. G.; Hensley, B. A.; Kanmae, T.</p> <p>2010-03-01</p> <p>High time resolution (10,000 frames per second) images of sprites combined with multistation concurrent video recordings have provided data for <span class="hlt">triangulation</span> of the altitude of the initial sprite onset. The high-speed images were obtained from the Langmuir Laboratory, New Mexico, during summer campaigns in 2007 and 2008 with video observations from sites at Portales, New Mexico, and Las Vegas, New Mexico. Sprites start with one or more downward-propagating streamer heads. The <span class="hlt">triangulated</span> onset altitudes of this initial downward streamer vary between 66 and 89 km. In some sprites the downward streamers are followed a little later by upward-propagating streamers. The upward streamers start from a lower altitude and existing luminous sprite structures and their <span class="hlt">triangulated</span> altitudes vary from 64 to 78 km. The downward streamers create C sprite characteristics, while the upward streamers form the broad diffuse tops of carrot sprites. In the sprites analyzed the higher onset altitudes for the downward-propagating initial streamers were associated with C sprites and the lower with carrot sprites, but our larger data set indicates that this is not generally the case. It appears that the dominant sprite types vary from year to year, indicating that some longer-lasting environmental parameter, such as mesospheric conductivity and composition or thunderstorm cloud dynamics, may play an important role in determining the types of sprites observed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/221032','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/221032"><span id="translatedtitle">Coefficient adaptive <span class="hlt">triangulation</span> for strongly anisotropic problems</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>D`Azevedo, E.F.; Romine, C.H.; Donato, J.M.</p> <p>1996-01-01</p> <p>Second order elliptic partial differential equations arise in many important applications, including flow through porous media, heat conduction, the distribution of electrical or magnetic potential. The prototype is the Laplace problem, which in discrete form produces a coefficient matrix that is relatively easy to solve in a regular domain. However, the presence of anisotropy produces a matrix whose condition number is increased, making the resulting linear system more difficult to solve. In this work, we take the anisotropy into account in the discretization by mapping each anisotropic region into a ``stretched`` coordinate space in which the anisotropy is removed. The region is then uniformly <span class="hlt">triangulated</span>, and the resulting <span class="hlt">triangulation</span> mapped back to the original space. The effect is to generate long slender triangles that are oriented in the direction of ``preferred flow.`` Slender triangles are generally regarded as numerically undesirable since they tend to cause poor conditioning; however, our <span class="hlt">triangulation</span> has the effect of producing effective isotropy, thus improving the condition number of the resulting coefficient matrix.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19770018839','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19770018839"><span id="translatedtitle">Market study: <span class="hlt">3</span>-<span class="hlt">D</span> eyetracker</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1977-01-01</p> <p>A market study of a proposed version of a <span class="hlt">3</span>-<span class="hlt">D</span> eyetracker for initial use at NASA's Ames Research Center was made. The commercialization potential of a simplified, less expensive <span class="hlt">3</span>-<span class="hlt">D</span> eyetracker was ascertained. Primary focus on present and potential users of eyetrackers, as well as present and potential manufacturers has provided an effective means of analyzing the prospects for commercialization.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=74916&keyword=soil+AND+radiation&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=64183124&CFTOKEN=81446066','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=74916&keyword=soil+AND+radiation&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=64183124&CFTOKEN=81446066"><span id="translatedtitle">Modular <span class="hlt">3</span>-<span class="hlt">D</span> Transport model</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>MT<span class="hlt">3</span><span class="hlt">D</span> was first developed by Chunmiao Zheng in 1990 at S.S. Papadopulos & Associates, Inc. with partial support from the U.S. Environmental Protection Agency (USEPA). Starting in 1990, MT<span class="hlt">3</span><span class="hlt">D</span> was released as a pubic domain code from the USEPA. Commercial versions with enhanced capab...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/7919882','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/7919882"><span id="translatedtitle">[<span class="hlt">3</span>-<span class="hlt">D</span> ultrasound in gastroenterology].</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zoller, W G; Liess, H</p> <p>1994-06-01</p> <p>Three-dimensional (<span class="hlt">3</span><span class="hlt">D</span>) sonography represents a development of noninvasive diagnostic imaging by real-time two-dimensional (2D) sonography. The use of transparent rotating scans, comparable to a block of glass, generates a <span class="hlt">3</span><span class="hlt">D</span> effect. The objective of the present study was to optimate <span class="hlt">3</span><span class="hlt">D</span> presentation of abdominal findings. Additional investigations were made with a new volumetric program to determine the volume of selected findings of the liver. The results were compared with the estimated volumes of 2D sonography and 2D computer tomography (CT). For the processing of <span class="hlt">3</span><span class="hlt">D</span> images, typical parameter constellations were found for the different findings, which facilitated processing of <span class="hlt">3</span><span class="hlt">D</span> images. In more than 75% of the cases examined we found an optimal <span class="hlt">3</span><span class="hlt">D</span> presentation of sonographic findings with respect to the evaluation criteria developed by us for the <span class="hlt">3</span><span class="hlt">D</span> imaging of processed data. Great differences were found for the estimated volumes of the findings of the liver concerning the three different techniques applied. <span class="hlt">3</span><span class="hlt">D</span> ultrasound represents a valuable method to judge morphological appearance in abdominal findings. The possibility of volumetric measurements enlarges its potential diagnostic significance. Further clinical investigations are necessary to find out if definite differentiation between benign and malign findings is possible. PMID:7919882</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1121334','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/1121334"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> World Building System</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p></p> <p>2013-10-30</p> <p>This video provides an overview of the Sandia National Laboratories developed <span class="hlt">3</span>-<span class="hlt">D</span> World Model Building capability that provides users with an immersive, texture rich <span class="hlt">3</span>-<span class="hlt">D</span> model of their environment in minutes using a laptop and color and depth camera.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/sciencecinema/biblio/1121334','SCIGOVIMAGE-SCICINEMA'); return false;" href="http://www.osti.gov/sciencecinema/biblio/1121334"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> World Building System</span></a></p> <p><a target="_blank" href="http://www.osti.gov/sciencecinema/">ScienceCinema</a></p> <p>None</p> <p>2014-02-26</p> <p>This video provides an overview of the Sandia National Laboratories developed <span class="hlt">3</span>-<span class="hlt">D</span> World Model Building capability that provides users with an immersive, texture rich <span class="hlt">3</span>-<span class="hlt">D</span> model of their environment in minutes using a laptop and color and depth camera.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1231744-llnl-earth3d','SCIGOV-ESTSC'); return false;" href="http://www.osti.gov/scitech/biblio/1231744-llnl-earth3d"><span id="translatedtitle">LLNL-Earth<span class="hlt">3</span><span class="hlt">D</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech/">Energy Science and Technology Software Center (ESTSC)</a></p> <p></p> <p>2013-10-01</p> <p>Earth<span class="hlt">3</span><span class="hlt">D</span> is a computer code designed to allow fast calculation of seismic rays and travel times through a <span class="hlt">3</span><span class="hlt">D</span> model of the Earth. LLNL is using this for earthquake location and global tomography efforts and such codes are of great interest to the Earth Science community.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004AN....325...83W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004AN....325...83W"><span id="translatedtitle">Euro<span class="hlt">3</span><span class="hlt">D</span> Science Conference</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Walsh, J. R.</p> <p>2004-02-01</p> <p>The Euro<span class="hlt">3</span><span class="hlt">D</span> RTN is an EU funded Research Training Network to foster the exploitation of <span class="hlt">3</span><span class="hlt">D</span> spectroscopy in Europe. <span class="hlt">3</span><span class="hlt">D</span> spectroscopy is a general term for spectroscopy of an area of the sky and derives its name from its two spatial + one spectral dimensions. There are an increasing number of instruments which use integral field devices to achieve spectroscopy of an area of the sky, either using lens arrays, optical fibres or image slicers, to pack spectra of multiple pixels on the sky (``spaxels'') onto a 2D detector. On account of the large volume of data and the special methods required to reduce and analyse <span class="hlt">3</span><span class="hlt">D</span> data, there are only a few centres of expertise and these are mostly involved with instrument developments. There is a perceived lack of expertise in <span class="hlt">3</span><span class="hlt">D</span> spectroscopy spread though the astronomical community and its use in the armoury of the observational astronomer is viewed as being highly specialised. For precisely this reason the Euro<span class="hlt">3</span><span class="hlt">D</span> RTN was proposed to train young researchers in this area and develop user tools to widen the experience with this particular type of data in Europe. The Euro<span class="hlt">3</span><span class="hlt">D</span> RTN is coordinated by Martin M. Roth (Astrophysikalisches Institut Potsdam) and has been running since July 2002. The first Euro<span class="hlt">3</span><span class="hlt">D</span> science conference was held in Cambridge, UK from 22 to 23 May 2003. The main emphasis of the conference was, in keeping with the RTN, to expose the work of the young post-docs who are funded by the RTN. In addition the team members from the eleven European institutes involved in Euro<span class="hlt">3</span><span class="hlt">D</span> also presented instrumental and observational developments. The conference was organized by Andy Bunker and held at the Institute of Astronomy. There were over thirty participants and 26 talks covered the whole range of application of <span class="hlt">3</span><span class="hlt">D</span> techniques. The science ranged from Galactic planetary nebulae and globular clusters to kinematics of nearby galaxies out to objects at high redshift. Several talks were devoted to reporting recent observations with newly</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26657435','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26657435"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> printing in dentistry.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Dawood, A; Marti Marti, B; Sauret-Jackson, V; Darwood, A</p> <p>2015-12-01</p> <p><span class="hlt">3</span><span class="hlt">D</span> printing has been hailed as a disruptive technology which will change manufacturing. Used in aerospace, defence, art and design, <span class="hlt">3</span><span class="hlt">D</span> printing is becoming a subject of great interest in surgery. The technology has a particular resonance with dentistry, and with advances in <span class="hlt">3</span><span class="hlt">D</span> imaging and modelling technologies such as cone beam computed tomography and intraoral scanning, and with the relatively long history of the use of CAD CAM technologies in dentistry, it will become of increasing importance. Uses of <span class="hlt">3</span><span class="hlt">D</span> printing include the production of drill guides for dental implants, the production of physical models for prosthodontics, orthodontics and surgery, the manufacture of dental, craniomaxillofacial and orthopaedic implants, and the fabrication of copings and frameworks for implant and dental restorations. This paper reviews the types of <span class="hlt">3</span><span class="hlt">D</span> printing technologies available and their various applications in dentistry and in maxillofacial surgery. PMID:26657435</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19900013774','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19900013774"><span id="translatedtitle">PLOT<span class="hlt">3</span><span class="hlt">D</span> user's manual</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Walatka, Pamela P.; Buning, Pieter G.; Pierce, Larry; Elson, Patricia A.</p> <p>1990-01-01</p> <p>PLOT<span class="hlt">3</span><span class="hlt">D</span> is a computer graphics program designed to visualize the grids and solutions of computational fluid dynamics. Seventy-four functions are available. Versions are available for many systems. PLOT<span class="hlt">3</span><span class="hlt">D</span> can handle multiple grids with a million or more grid points, and can produce varieties of model renderings, such as wireframe or flat shaded. Output from PLOT<span class="hlt">3</span><span class="hlt">D</span> can be used in animation programs. The first part of this manual is a tutorial that takes the reader, keystroke by keystroke, through a PLOT<span class="hlt">3</span><span class="hlt">D</span> session. The second part of the manual contains reference chapters, including the helpfile, data file formats, advice on changing PLOT<span class="hlt">3</span><span class="hlt">D</span>, and sample command files.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19940002506&hterms=Tools+physicists&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DTools%2Bphysicists','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19940002506&hterms=Tools+physicists&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DTools%2Bphysicists"><span id="translatedtitle">PLOT<span class="hlt">3</span><span class="hlt">D</span>/AMES, APOLLO UNIX VERSION USING GMR<span class="hlt">3</span><span class="hlt">D</span> (WITH TURB<span class="hlt">3</span><span class="hlt">D</span>)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Buning, P.</p> <p>1994-01-01</p> <p>PLOT<span class="hlt">3</span><span class="hlt">D</span> is an interactive graphics program designed to help scientists visualize computational fluid dynamics (CFD) grids and solutions. Today, supercomputers and CFD algorithms can provide scientists with simulations of such highly complex phenomena that obtaining an understanding of the simulations has become a major problem. Tools which help the scientist visualize the simulations can be of tremendous aid. PLOT<span class="hlt">3</span><span class="hlt">D</span>/AMES offers more functions and features, and has been adapted for more types of computers than any other CFD graphics program. Version 3.6b+ is supported for five computers and graphic libraries. Using PLOT<span class="hlt">3</span><span class="hlt">D</span>, CFD physicists can view their computational models from any angle, observing the physics of problems and the quality of solutions. As an aid in designing aircraft, for example, PLOT<span class="hlt">3</span><span class="hlt">D</span>'s interactive computer graphics can show vortices, temperature, reverse flow, pressure, and dozens of other characteristics of air flow during flight. As critical areas become obvious, they can easily be studied more closely using a finer grid. PLOT<span class="hlt">3</span><span class="hlt">D</span> is part of a computational fluid dynamics software cycle. First, a program such as 3DGRAPE (ARC-12620) helps the scientist generate computational grids to model an object and its surrounding space. Once the grids have been designed and parameters such as the angle of attack, Mach number, and Reynolds number have been specified, a "flow-solver" program such as INS<span class="hlt">3</span><span class="hlt">D</span> (ARC-11794 or COS-10019) solves the system of equations governing fluid flow, usually on a supercomputer. Grids sometimes have as many as two million points, and the "flow-solver" produces a solution file which contains density, x- y- and z-momentum, and stagnation energy for each grid point. With such a solution file and a grid file containing up to 50 grids as input, PLOT<span class="hlt">3</span><span class="hlt">D</span> can calculate and graphically display any one of 74 functions, including shock waves, surface pressure, velocity vectors, and particle traces. PLOT<span class="hlt">3</span><span class="hlt">D</span>'s 74 functions are organized into</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19940002508&hterms=Tools+physicists&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DTools%2Bphysicists','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19940002508&hterms=Tools+physicists&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DTools%2Bphysicists"><span id="translatedtitle">PLOT<span class="hlt">3</span><span class="hlt">D</span>/AMES, APOLLO UNIX VERSION USING GMR<span class="hlt">3</span><span class="hlt">D</span> (WITHOUT TURB<span class="hlt">3</span><span class="hlt">D</span>)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Buning, P.</p> <p>1994-01-01</p> <p>PLOT<span class="hlt">3</span><span class="hlt">D</span> is an interactive graphics program designed to help scientists visualize computational fluid dynamics (CFD) grids and solutions. Today, supercomputers and CFD algorithms can provide scientists with simulations of such highly complex phenomena that obtaining an understanding of the simulations has become a major problem. Tools which help the scientist visualize the simulations can be of tremendous aid. PLOT<span class="hlt">3</span><span class="hlt">D</span>/AMES offers more functions and features, and has been adapted for more types of computers than any other CFD graphics program. Version 3.6b+ is supported for five computers and graphic libraries. Using PLOT<span class="hlt">3</span><span class="hlt">D</span>, CFD physicists can view their computational models from any angle, observing the physics of problems and the quality of solutions. As an aid in designing aircraft, for example, PLOT<span class="hlt">3</span><span class="hlt">D</span>'s interactive computer graphics can show vortices, temperature, reverse flow, pressure, and dozens of other characteristics of air flow during flight. As critical areas become obvious, they can easily be studied more closely using a finer grid. PLOT<span class="hlt">3</span><span class="hlt">D</span> is part of a computational fluid dynamics software cycle. First, a program such as 3DGRAPE (ARC-12620) helps the scientist generate computational grids to model an object and its surrounding space. Once the grids have been designed and parameters such as the angle of attack, Mach number, and Reynolds number have been specified, a "flow-solver" program such as INS<span class="hlt">3</span><span class="hlt">D</span> (ARC-11794 or COS-10019) solves the system of equations governing fluid flow, usually on a supercomputer. Grids sometimes have as many as two million points, and the "flow-solver" produces a solution file which contains density, x- y- and z-momentum, and stagnation energy for each grid point. With such a solution file and a grid file containing up to 50 grids as input, PLOT<span class="hlt">3</span><span class="hlt">D</span> can calculate and graphically display any one of 74 functions, including shock waves, surface pressure, velocity vectors, and particle traces. PLOT<span class="hlt">3</span><span class="hlt">D</span>'s 74 functions are organized into</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/456334','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/456334"><span id="translatedtitle">A <span class="hlt">3</span>-<span class="hlt">d</span> modular gripper design tool</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Brown, R.G.; Brost, R.C.</p> <p>1997-02-01</p> <p>Modular fixturing kits are sets of components used for flexible, rapid construction of fixtures. A modular vise is a parallel-jaw vise, each jaw of which is a modular fixture plate with a regular grid of precisely positioned holes. To fixture a part, one places pins in some of the holes so that when the vise is closed, the part is reliably located and completely <span class="hlt">constrained</span>. The modular vise concept can be adapted easily to the design of modular parallel-jaw grippers for robots. By attaching a grid-plate to each jaw of a parallel-jaw gripper, one gains the ability to easily construct high-quality grasps for a wide variety of parts from a standard set of hardware. Wallack and Canny developed an algorithm for planning planar grasp configurations for the modular vise. In this paper, the authors expand this work to produce a <span class="hlt">3</span>-<span class="hlt">d</span> fixture/gripper design tool. They describe several analyses they have added to the planar algorithm, including a <span class="hlt">3</span>-<span class="hlt">d</span> grasp quality metric based on force information, <span class="hlt">3</span>-<span class="hlt">d</span> geometric loading analysis, and inter-gripper interference analysis. Finally, the authors describe two applications of their code. One of these is an internal application at Sandia, while the other shows a potential use of the code for designing part of an agile assembly line.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ISPArXL55..195R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ISPArXL55..195R"><span id="translatedtitle">Filming Underwater in <span class="hlt">3</span><span class="hlt">d</span> Respecting Stereographic Rules</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rinaldi, R.; Hordosch, H.</p> <p>2015-04-01</p> <p>After an experimental phase of many years, <span class="hlt">3</span><span class="hlt">D</span> filming is now effective and successful. Improvements are still possible, but the film industry achieved memorable success on <span class="hlt">3</span><span class="hlt">D</span> movie's box offices due to the overall quality of its products. Special environments such as space ("Gravity") and the underwater realm look perfect to be reproduced in <span class="hlt">3</span><span class="hlt">D</span>. "Filming in space" was possible in "Gravity" using special effects and computer graphic. The underwater realm is still difficult to be handled. Underwater filming in <span class="hlt">3</span><span class="hlt">D</span> was not that easy and effective as filming in 2D, since not long ago. After almost 3 years of research, a French, Austrian and Italian team realized a perfect tool to film underwater, in <span class="hlt">3</span><span class="hlt">D</span>, without any <span class="hlt">constrains</span>. This allows filmmakers to bring the audience deep inside an environment where they most probably will never have the chance to be.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26066320','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26066320"><span id="translatedtitle">Bioprinting of <span class="hlt">3</span><span class="hlt">D</span> hydrogels.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Stanton, M M; Samitier, J; Sánchez, S</p> <p>2015-08-01</p> <p>Three-dimensional (<span class="hlt">3</span><span class="hlt">D</span>) bioprinting has recently emerged as an extension of <span class="hlt">3</span><span class="hlt">D</span> material printing, by using biocompatible or cellular components to build structures in an additive, layer-by-layer methodology for encapsulation and culture of cells. These <span class="hlt">3</span><span class="hlt">D</span> systems allow for cell culture in a suspension for formation of highly organized tissue or controlled spatial orientation of cell environments. The in vitro <span class="hlt">3</span><span class="hlt">D</span> cellular environments simulate the complexity of an in vivo environment and natural extracellular matrices (ECM). This paper will focus on bioprinting utilizing hydrogels as <span class="hlt">3</span><span class="hlt">D</span> scaffolds. Hydrogels are advantageous for cell culture as they are highly permeable to cell culture media, nutrients, and waste products generated during metabolic cell processes. They have the ability to be fabricated in customized shapes with various material properties with dimensions at the micron scale. <span class="hlt">3</span><span class="hlt">D</span> hydrogels are a reliable method for biocompatible <span class="hlt">3</span><span class="hlt">D</span> printing and have applications in tissue engineering, drug screening, and organ on a chip models. PMID:26066320</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2012SPIE.8288E..08A&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2012SPIE.8288E..08A&link_type=ABSTRACT"><span id="translatedtitle">Unassisted <span class="hlt">3</span><span class="hlt">D</span> camera calibration</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Atanassov, Kalin; Ramachandra, Vikas; Nash, James; Goma, Sergio R.</p> <p>2012-03-01</p> <p>With the rapid growth of <span class="hlt">3</span><span class="hlt">D</span> technology, <span class="hlt">3</span><span class="hlt">D</span> image capture has become a critical part of the <span class="hlt">3</span><span class="hlt">D</span> feature set on mobile phones. <span class="hlt">3</span><span class="hlt">D</span> image quality is affected by the scene geometry as well as on-the-device processing. An automatic <span class="hlt">3</span><span class="hlt">D</span> system usually assumes known camera poses accomplished by factory calibration using a special chart. In real life settings, pose parameters estimated by factory calibration can be negatively impacted by movements of the lens barrel due to shaking, focusing, or camera drop. If any of these factors displaces the optical axes of either or both cameras, vertical disparity might exceed the maximum tolerable margin and the <span class="hlt">3</span><span class="hlt">D</span> user may experience eye strain or headaches. To make <span class="hlt">3</span><span class="hlt">D</span> capture more practical, one needs to consider unassisted (on arbitrary scenes) calibration. In this paper, we propose an algorithm that relies on detection and matching of keypoints between left and right images. Frames containing erroneous matches, along with frames with insufficiently rich keypoint constellations, are detected and discarded. Roll, pitch yaw , and scale differences between left and right frames are then estimated. The algorithm performance is evaluated in terms of the remaining vertical disparity as compared to the maximum tolerable vertical disparity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016TDR.....7...91S&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016TDR.....7...91S&link_type=ABSTRACT"><span id="translatedtitle">Novel <span class="hlt">3</span><span class="hlt">D</span> Compression Methods for Geometry, Connectivity and Texture</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Siddeq, M. M.; Rodrigues, M. A.</p> <p>2016-06-01</p> <p>A large number of applications in medical visualization, games, engineering design, entertainment, heritage, e-commerce and so on require the transmission of <span class="hlt">3</span><span class="hlt">D</span> models over the Internet or over local networks. <span class="hlt">3</span><span class="hlt">D</span> data compression is an important requirement for fast data storage, access and transmission within bandwidth limitations. The Wavefront OBJ (object) file format is commonly used to share models due to its clear simple design. Normally each OBJ file contains a large amount of data (e.g. vertices and <span class="hlt">triangulated</span> faces, normals, texture coordinates and other parameters) describing the mesh surface. In this paper we introduce a new method to compress geometry, connectivity and texture coordinates by a novel Geometry Minimization Algorithm (GM-Algorithm) in connection with arithmetic coding. First, each vertex ( x, y, z) coordinates are encoded to a single value by the GM-Algorithm. Second, triangle faces are encoded by computing the differences between two adjacent vertex locations, which are compressed by arithmetic coding together with texture coordinates. We demonstrate the method on large data sets achieving compression ratios between 87 and 99 % without reduction in the number of reconstructed vertices and triangle faces. The decompression step is based on a Parallel Fast Matching Search Algorithm (Parallel-FMS) to recover the structure of the <span class="hlt">3</span><span class="hlt">D</span> mesh. A comparative analysis of compression ratios is provided with a number of commonly used <span class="hlt">3</span><span class="hlt">D</span> file formats such as VRML, OpenCTM and STL highlighting the performance and effectiveness of the proposed method.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999SPIE.3640..125Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1999SPIE.3640..125Y"><span id="translatedtitle">Robust <span class="hlt">3</span><span class="hlt">D</span> reconstruction system for human jaw modeling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yamany, Sameh M.; Farag, Aly A.; Tazman, David; Farman, Allan G.</p> <p>1999-03-01</p> <p>This paper presents a model-based vision system for dentistry that will replace traditional approaches used in diagnosis, treatment planning and surgical simulation. Dentistry requires accurate <span class="hlt">3</span><span class="hlt">D</span> representation of the teeth and jaws for many diagnostic and treatment purposes. For example orthodontic treatment involves the application of force systems to teeth over time to correct malocclusion. In order to evaluate tooth movement progress, the orthodontists monitors this movement by means of visual inspection, intraoral measurements, fabrication of plastic models, photographs and radiographs, a process which is both costly and time consuming. In this paper an integrate system has been developed to record the patient's occlusion using computer vision. Data is acquired with an intraoral video camera. A modified shape from shading (SFS) technique, using perspective projection and camera calibration, is used to extract accurate <span class="hlt">3</span><span class="hlt">D</span> information from a sequence of 2D images of the jaw. A new technique for <span class="hlt">3</span><span class="hlt">D</span> data registration, using a Grid Closest Point transform and genetic algorithms, is used to register the SFS output. <span class="hlt">Triangulization</span> is then performed, and a solid <span class="hlt">3</span><span class="hlt">D</span> model is obtained via a rapid prototype machine.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2637860','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2637860"><span id="translatedtitle">Arena<span class="hlt">3</span><span class="hlt">D</span>: visualization of biological networks in <span class="hlt">3</span><span class="hlt">D</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Pavlopoulos, Georgios A; O'Donoghue, Seán I; Satagopam, Venkata P; Soldatos, Theodoros G; Pafilis, Evangelos; Schneider, Reinhard</p> <p>2008-01-01</p> <p>Background Complexity is a key problem when visualizing biological networks; as the number of entities increases, most graphical views become incomprehensible. Our goal is to enable many thousands of entities to be visualized meaningfully and with high performance. Results We present a new visualization tool, Arena<span class="hlt">3</span><span class="hlt">D</span>, which introduces a new concept of staggered layers in <span class="hlt">3</span><span class="hlt">D</span> space. Related data – such as proteins, chemicals, or pathways – can be grouped onto separate layers and arranged via layout algorithms, such as Fruchterman-Reingold, distance geometry, and a novel hierarchical layout. Data on a layer can be clustered via k-means, affinity propagation, Markov clustering, neighbor joining, tree clustering, or UPGMA ('unweighted pair-group method with arithmetic mean'). A simple input format defines the name and URL for each node, and defines connections or similarity scores between pairs of nodes. The use of Arena<span class="hlt">3</span><span class="hlt">D</span> is illustrated with datasets related to Huntington's disease. Conclusion Arena<span class="hlt">3</span><span class="hlt">D</span> is a user friendly visualization tool that is able to visualize biological or any other network in <span class="hlt">3</span><span class="hlt">D</span> space. It is free for academic use and runs on any platform. It can be downloaded or lunched directly from . Java<span class="hlt">3</span><span class="hlt">D</span> library and Java 1.5 need to be pre-installed for the software to run. PMID:19040715</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_13");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_8 --> <div id="page_9" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_13");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="161"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013APS..DFDL21004O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013APS..DFDL21004O"><span id="translatedtitle">Fdf in US<span class="hlt">3</span><span class="hlt">D</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Otis, Collin; Ferrero, Pietro; Candler, Graham; Givi, Peyman</p> <p>2013-11-01</p> <p>The scalar filtered mass density function (SFMDF) methodology is implemented into the computer code US<span class="hlt">3</span><span class="hlt">D</span>. This is an unstructured Eulerian finite volume hydrodynamic solver and has proven very effective for simulation of compressible turbulent flows. The resulting SFMDF-US<span class="hlt">3</span><span class="hlt">D</span> code is employed for large eddy simulation (LES) on unstructured meshes. Simulations are conducted of subsonic and supersonic flows under non-reacting and reacting conditions. The consistency and the accuracy of the simulated results are assessed along with appraisal of the overall performance of the methodology. The SFMDF-US<span class="hlt">3</span><span class="hlt">D</span> is now capable of simulating high speed flows in complex configurations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/348942','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/348942"><span id="translatedtitle">Strategies for nonobtuse boundary Delaunay <span class="hlt">triangulations</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Murphy, M. |; Gable, C.W.</p> <p>1998-12-31</p> <p>Delaunay <span class="hlt">Triangulations</span> with nonobtuse triangles at the boundaries satisfy a minimal requirement for Control Volume meshes. They motivate this quality requirement, discuss it in context with others that have been proposed, and give point placement strategies that generate the fewest or close to the fewest number of Steiner points needed to satisfy it for a particular problem instance. The advantage is that this strategy places a number of Steiner points proportional to the combinatorial size of the input rather than the local feature size, resulting in far fewer points in many cases.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016OptCo.368....1Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016OptCo.368....1Y"><span id="translatedtitle">Heterodyne <span class="hlt">3</span><span class="hlt">D</span> ghost imaging</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yang, Xu; Zhang, Yong; Yang, Chenghua; Xu, Lu; Wang, Qiang; Zhao, Yuan</p> <p>2016-06-01</p> <p>Conventional three dimensional (<span class="hlt">3</span><span class="hlt">D</span>) ghost imaging measures range of target based on pulse fight time measurement method. Due to the limit of data acquisition system sampling rate, range resolution of the conventional <span class="hlt">3</span><span class="hlt">D</span> ghost imaging is usually low. In order to take off the effect of sampling rate to range resolution of <span class="hlt">3</span><span class="hlt">D</span> ghost imaging, a heterodyne <span class="hlt">3</span><span class="hlt">D</span> ghost imaging (HGI) system is presented in this study. The source of HGI is a continuous wave laser instead of pulse laser. Temporal correlation and spatial correlation of light are both utilized to obtain the range image of target. Through theory analysis and numerical simulations, it is demonstrated that HGI can obtain high range resolution image with low sampling rate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/543001','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/543001"><span id="translatedtitle">Wavefront construction in <span class="hlt">3</span>-<span class="hlt">D</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Chilcoat, S.R. Hildebrand, S.T.</p> <p>1995-12-31</p> <p>Travel time computation in inhomogeneous media is essential for pre-stack Kirchhoff imaging in areas such as the sub-salt province in the Gulf of Mexico. The 2D algorithm published by Vinje, et al, has been extended to <span class="hlt">3</span><span class="hlt">D</span> to compute wavefronts in complicated inhomogeneous media. The <span class="hlt">3</span><span class="hlt">D</span> wavefront construction algorithm provides many advantages over conventional ray tracing and other methods of computing travel times in <span class="hlt">3</span><span class="hlt">D</span>. The algorithm dynamically maintains a reasonably consistent ray density without making a priori guesses at the number of rays to shoot. The determination of caustics in <span class="hlt">3</span><span class="hlt">D</span> is a straight forward geometric procedure. The wavefront algorithm also enables the computation of multi-valued travel time surfaces.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015APS..MARL36014C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015APS..MARL36014C"><span id="translatedtitle">Combinatorial <span class="hlt">3</span><span class="hlt">D</span> Mechanical Metamaterials</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Coulais, Corentin; Teomy, Eial; de Reus, Koen; Shokef, Yair; van Hecke, Martin</p> <p>2015-03-01</p> <p>We present a class of elastic structures which exhibit <span class="hlt">3</span><span class="hlt">D</span>-folding motion. Our structures consist of cubic lattices of anisotropic unit cells that can be tiled in a complex combinatorial fashion. We design and <span class="hlt">3</span><span class="hlt">d</span>-print this complex ordered mechanism, in which we combine elastic hinges and defects to tailor the mechanics of the material. Finally, we use this large design space to encode smart functionalities such as surface patterning and multistability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19930040784&hterms=Automobiles&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DAutomobiles','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19930040784&hterms=Automobiles&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DAutomobiles"><span id="translatedtitle">Unstructured <span class="hlt">3</span><span class="hlt">D</span> Delaunay mesh generation applied to planes, trains and automobiles</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Blake, Kenneth R.; Spragle, Gregory S.</p> <p>1993-01-01</p> <p>Technical issues associated with domain-tessellation production, including initial boundary node <span class="hlt">triangulation</span> and volume mesh refinement, are presented for the 'TGrid' <span class="hlt">3</span><span class="hlt">D</span> Delaunay unstructured grid generation program. The approach employed is noted to be capable of preserving predefined triangular surface facets in the final tessellation. The capabilities of the approach are demonstrated by generating grids about an entire fighter aircraft configuration, a train, and a wind tunnel model of an automobile.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014CG.....66..121L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014CG.....66..121L"><span id="translatedtitle">A <span class="hlt">triangulation</span>-based approach to automatically repair GIS polygons</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ledoux, Hugo; Arroyo Ohori, Ken; Meijers, Martijn</p> <p>2014-05-01</p> <p>Although the validation of a single GIS polygon can be considered as a solved issue, the repair of an invalid polygon has not received much attention and is still in practice a semi-manual and time-consuming task. We investigate in this paper algorithms to automatically repair a single polygon. Automated repair algorithms can be considered as interpreting ambiguous or ill-defined polygons and returning a coherent and clearly defined output (the definition of the international standards in our case). We present a novel approach, based on the use of a <span class="hlt">constrained</span> <span class="hlt">triangulation</span>, to automatically repair invalid polygons. Our approach is conceptually simple and easy to implement as it is mostly based on labelling triangles. It is also flexible: it permits us to implement different repair paradigms (we describe two in the paper). We have implemented our algorithms, and we report on experiments made with large real-world polygons that are often used by practitioners in different disciplines. We show that our approach is faster and more scalable than alternative tools.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2014SPIE.9143E..5ED&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2014SPIE.9143E..5ED&link_type=ABSTRACT"><span id="translatedtitle">From <span class="hlt">3</span><span class="hlt">D</span> view to <span class="hlt">3</span><span class="hlt">D</span> print</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dima, M.; Farisato, G.; Bergomi, M.; Viotto, V.; Magrin, D.; Greggio, D.; Farinato, J.; Marafatto, L.; Ragazzoni, R.; Piazza, D.</p> <p>2014-08-01</p> <p>In the last few years <span class="hlt">3</span><span class="hlt">D</span> printing is getting more and more popular and used in many fields going from manufacturing to industrial design, architecture, medical support and aerospace. <span class="hlt">3</span><span class="hlt">D</span> printing is an evolution of bi-dimensional printing, which allows to obtain a solid object from a <span class="hlt">3</span><span class="hlt">D</span> model, realized with a <span class="hlt">3</span><span class="hlt">D</span> modelling software. The final product is obtained using an additive process, in which successive layers of material are laid down one over the other. A <span class="hlt">3</span><span class="hlt">D</span> printer allows to realize, in a simple way, very complex shapes, which would be quite difficult to be produced with dedicated conventional facilities. Thanks to the fact that the <span class="hlt">3</span><span class="hlt">D</span> printing is obtained superposing one layer to the others, it doesn't need any particular work flow and it is sufficient to simply draw the model and send it to print. Many different kinds of <span class="hlt">3</span><span class="hlt">D</span> printers exist based on the technology and material used for layer deposition. A common material used by the toner is ABS plastics, which is a light and rigid thermoplastic polymer, whose peculiar mechanical properties make it diffusely used in several fields, like pipes production and cars interiors manufacturing. I used this technology to create a 1:1 scale model of the telescope which is the hardware core of the space small mission CHEOPS (CHaracterising ExOPlanets Satellite) by ESA, which aims to characterize EXOplanets via transits observations. The telescope has a Ritchey-Chrétien configuration with a 30cm aperture and the launch is foreseen in 2017. In this paper, I present the different phases for the realization of such a model, focusing onto pros and cons of this kind of technology. For example, because of the finite printable volume (10×10×12 inches in the x, y and z directions respectively), it has been necessary to split the largest parts of the instrument in smaller components to be then reassembled and post-processed. A further issue is the resolution of the printed material, which is expressed in terms of layers</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/10148829','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/10148829"><span id="translatedtitle">Finding a covering <span class="hlt">triangulation</span> whose maximum angle is provably small</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Mitchell, S.A.; Park, J.K.</p> <p>1993-03-03</p> <p>Given a planar straight-line graph, we find a covering <span class="hlt">triangulation</span> whose maximum angle is as small as possible. A covering <span class="hlt">triangulation</span> is a <span class="hlt">triangulation</span> whose vertex set contains the input vertex set and whose edge set contains the input edge set. Such a <span class="hlt">triangulation</span> differs from the usual Steiner <span class="hlt">triangulation</span> in that we may not add a Steiner vertex on any input edge. Covering <span class="hlt">triangulations</span> provide a convenient method for <span class="hlt">triangulating</span> multiple regions sharing a common boundary, as each region can be <span class="hlt">triangulated</span> independently. As it is possible that no finite covering <span class="hlt">triangulation</span> is optimal in terms of its maximum angle, we propose an approximation algorithm. Our algorithm produces a covering <span class="hlt">triangulation</span> whose maximum angle {gamma} is probably close to {gamma}{sub opt}, a lower bound on the maximum angle in any covering <span class="hlt">triangulation</span> of the input graph. Note that we must have {gamma} {le} 3{gamma}{sub opt}, since we always have {gamma}{sub opt} {ge} {pi}/3 and no <span class="hlt">triangulation</span> can contain an angle of size greater than {pi}. We prove something significantly stronger. We show that {pi} {minus} {gamma} {ge} ({pi} {minus} {gamma}{sub opt})/6, i.e., our {gamma} is not much closer to {pi} than is {gamma}{sub opt}. This result represents the first nontrivial bound on a covering <span class="hlt">triangulation`s</span> maximum angle. We require a subroutine for the following problem: Given a polygon with holes, find a Steiner <span class="hlt">triangulation</span> whose maximum angle is bounded away from {pi}. No angle larger than 8{pi}/9 is sufficient for the bound on {gamma} claimed above. The number of Steiner vertices added by our algorithm and its running time are highly dependent on the corresponding bounds for the subroutine. Given an n-vertex planar straight-line graph, we require O(n + S(n)) Steiner vertices and O(n log n + T(n)) time, where S(n) is the number of Steiner vertices added by the subroutine and T(n) is its running time for an O(n)-vertex polygon with holes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012SPIE.8288E..19S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012SPIE.8288E..19S"><span id="translatedtitle">YouDash<span class="hlt">3</span><span class="hlt">D</span>: exploring stereoscopic <span class="hlt">3</span><span class="hlt">D</span> gaming for <span class="hlt">3</span><span class="hlt">D</span> movie theaters</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schild, Jonas; Seele, Sven; Masuch, Maic</p> <p>2012-03-01</p> <p>Along with the success of the digitally revived stereoscopic cinema, events beyond <span class="hlt">3</span><span class="hlt">D</span> movies become attractive for movie theater operators, i.e. interactive <span class="hlt">3</span><span class="hlt">D</span> games. In this paper, we present a case that explores possible challenges and solutions for interactive <span class="hlt">3</span><span class="hlt">D</span> games to be played by a movie theater audience. We analyze the setting and showcase current issues related to lighting and interaction. Our second focus is to provide gameplay mechanics that make special use of stereoscopy, especially depth-based game design. Based on these results, we present YouDash<span class="hlt">3</span><span class="hlt">D</span>, a game prototype that explores public stereoscopic gameplay in a reduced kiosk setup. It features live <span class="hlt">3</span><span class="hlt">D</span> HD video stream of a professional stereo camera rig rendered in a real-time game scene. We use the effect to place the stereoscopic effigies of players into the digital game. The game showcases how stereoscopic vision can provide for a novel depth-based game mechanic. Projected trigger zones and distributed clusters of the audience video allow for easy adaptation to larger audiences and <span class="hlt">3</span><span class="hlt">D</span> movie theater gaming.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/20679031','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/20679031"><span id="translatedtitle"><span class="hlt">3</span>-<span class="hlt">D</span> target-based distributed smart camera network localization.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kassebaum, John; Bulusu, Nirupama; Feng, Wu-Chi</p> <p>2010-10-01</p> <p>For distributed smart camera networks to perform vision-based tasks such as subject recognition and tracking, every camera's position and orientation relative to a single <span class="hlt">3</span>-<span class="hlt">D</span> coordinate frame must be accurately determined. In this paper, we present a new camera network localization solution that requires successively showing a <span class="hlt">3</span>-<span class="hlt">D</span> feature point-rich target to all cameras, then using the known geometry of a <span class="hlt">3</span>-<span class="hlt">D</span> target, cameras estimate and decompose projection matrices to compute their position and orientation relative to the coordinatization of the <span class="hlt">3</span>-<span class="hlt">D</span> target's feature points. As each <span class="hlt">3</span>-<span class="hlt">D</span> target position establishes a distinct coordinate frame, cameras that view more than one <span class="hlt">3</span>-<span class="hlt">D</span> target position compute translations and rotations relating different positions' coordinate frames and share the transform data with neighbors to facilitate realignment of all cameras to a single coordinate frame. Compared to other localization solutions that use opportunistically found visual data, our solution is more suitable to battery-powered, processing-<span class="hlt">constrained</span> camera networks because it requires communication only to determine simultaneous target viewings and for passing transform data. Additionally, our solution requires only pairwise view overlaps of sufficient size to see the <span class="hlt">3</span>-<span class="hlt">D</span> target and detect its feature points, while also giving camera positions in meaningful units. We evaluate our algorithm in both real and simulated smart camera networks. In the real network, position error is less than 1 ('') when the <span class="hlt">3</span>-<span class="hlt">D</span> target's feature points fill only 2.9% of the frame area. PMID:20679031</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011vire.book..139W&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011vire.book..139W&link_type=ABSTRACT"><span id="translatedtitle">Remote <span class="hlt">3</span><span class="hlt">D</span> Medical Consultation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Welch, Greg; Sonnenwald, Diane H.; Fuchs, Henry; Cairns, Bruce; Mayer-Patel, Ketan; Yang, Ruigang; State, Andrei; Towles, Herman; Ilie, Adrian; Krishnan, Srinivas; Söderholm, Hanna M.</p> <p></p> <p>Two-dimensional (2D) video-based telemedical consultation has been explored widely in the past 15-20 years. Two issues that seem to arise in most relevant case studies are the difficulty associated with obtaining the desired 2D camera views, and poor depth perception. To address these problems we are exploring the use of a small array of cameras to synthesize a spatially continuous range of dynamic three-dimensional (<span class="hlt">3</span><span class="hlt">D</span>) views of a remote environment and events. The <span class="hlt">3</span><span class="hlt">D</span> views can be sent across wired or wireless networks to remote viewers with fixed displays or mobile devices such as a personal digital assistant (PDA). The viewpoints could be specified manually or automatically via user head or PDA tracking, giving the remote viewer virtual head- or hand-slaved (PDA-based) remote cameras for mono or stereo viewing. We call this idea remote <span class="hlt">3</span><span class="hlt">D</span> medical consultation (3DMC). In this article we motivate and explain the vision for <span class="hlt">3</span><span class="hlt">D</span> medical consultation; we describe the relevant computer vision/graphics, display, and networking research; we present a proof-of-concept prototype system; and we present some early experimental results supporting the general hypothesis that <span class="hlt">3</span><span class="hlt">D</span> remote medical consultation could offer benefits over conventional 2D televideo.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20020080311','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20020080311"><span id="translatedtitle">Speaking Volumes About <span class="hlt">3</span>-<span class="hlt">D</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2002-01-01</p> <p>In 1999, Genex submitted a proposal to Stennis Space Center for a volumetric <span class="hlt">3</span>-<span class="hlt">D</span> display technique that would provide multiple users with a 360-degree perspective to simultaneously view and analyze <span class="hlt">3</span>-<span class="hlt">D</span> data. The futuristic capabilities of the VolumeViewer(R) have offered tremendous benefits to commercial users in the fields of medicine and surgery, air traffic control, pilot training and education, computer-aided design/computer-aided manufacturing, and military/battlefield management. The technology has also helped NASA to better analyze and assess the various data collected by its satellite and spacecraft sensors. Genex capitalized on its success with Stennis by introducing two separate products to the commercial market that incorporate key elements of the <span class="hlt">3</span>-<span class="hlt">D</span> display technology designed under an SBIR contract. The company Rainbow <span class="hlt">3</span><span class="hlt">D</span>(R) imaging camera is a novel, three-dimensional surface profile measurement system that can obtain a full-frame <span class="hlt">3</span>-<span class="hlt">D</span> image in less than 1 second. The third product is the 360-degree OmniEye(R) video system. Ideal for intrusion detection, surveillance, and situation management, this unique camera system offers a continuous, panoramic view of a scene in real time.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/6397749','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/6397749"><span id="translatedtitle">Area and volume coherence for efficient visualization of <span class="hlt">3</span><span class="hlt">D</span> scalar functions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Max, N. California Univ., Davis, CA ); Hanrahan, P. ); Crawfis, R. )</p> <p>1990-01-01</p> <p>We present an algorithm for compositing a combination of density clouds and contour surfaces used to represent a scalar function on a <span class="hlt">3</span>-<span class="hlt">D</span> volume. The volume is divided into convex polyhedra, at whose vertices the function is known, and the polyhedra are sorted in depth before compositing. For data given at scattered <span class="hlt">3</span>-<span class="hlt">D</span> points, we show that this sorting can be done in O(n) time if we chose the tetrahedra in the Delaunay <span class="hlt">triangulation</span> as the polyhedra. The integrals for cloud opacity and visible cloud intensity along a ray through a convex polyhedron are computed analytically, and this computation is coherent across the polyhedron's area. 33 refs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2013AIPC.1558.2042M&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2013AIPC.1558.2042M&link_type=ABSTRACT"><span id="translatedtitle">An efficient modified Gabriel method for <span class="hlt">triangulating</span> complex fractured media for multiphase flow simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mustapha, Hussein; Rouxel-Labbé, Mael; Abbas, Hicham</p> <p>2013-10-01</p> <p>Fractured reservoirs and aquifers are complex domains where discrete fractures are internal <span class="hlt">constraining</span> boundaries. The Delaunay <span class="hlt">triangulation</span> of a fractured medium generally does not conform to the fracture boundaries and recovering the fracture elements may violate the Delaunay empty-circle (2D) criterion, which may lead to a low-quality <span class="hlt">triangulation</span>. This paper presents a new approach based on the combined Gabriel and Delaunay methods. A modified Gabriel condition of edge-empty-circle is introduced. In a first stage, the fracture edges violating the modified Gabriel criterion are released and then followed by a Delaunay <span class="hlt">triangulation</span> with the rest of the fracture constraints. The released fracture edges are approximated by the edges of the Delaunay triangles in a postprocessing stage. The final representation of the fractures might be slightly different, but a very accurate solution is always maintained. The method has the capability to generate fine grids and to offer an accurate and good-quality grid. Numerical examples are presented to assess the efficiency of the proposed method.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014SPIE.9282E..1TL','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014SPIE.9282E..1TL"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> reconstruction with two webcams and a laser line projector</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Dongdong; Hui, Bingwei; Qiu, Shaohua; Wen, Gongjian</p> <p>2014-09-01</p> <p>Three-dimensional (<span class="hlt">3</span><span class="hlt">D</span>) reconstruction is one of the most attractive research topics in photogrammetry and computer vision. Nowadays <span class="hlt">3</span><span class="hlt">D</span> reconstruction with simple and consumable equipment plays an important role. In this paper, a <span class="hlt">3</span><span class="hlt">D</span> reconstruction desktop system is built based on binocular stereo vision using a laser scanner. The hardware requirements are a simple commercial hand-held laser line projector and two common webcams for image acquisition. Generally, <span class="hlt">3</span><span class="hlt">D</span> reconstruction based on passive <span class="hlt">triangulation</span> methods requires point correspondences among various viewpoints. The development of matching algorithms remains a challenging task in computer vision. In our proposal, with the help of a laser line projector, stereo correspondences are established robustly from epipolar geometry and the laser shadow on the scanned object. To establish correspondences more conveniently, epipolar rectification is employed using Bouguet's method after stereo calibration with a printed chessboard. <span class="hlt">3</span><span class="hlt">D</span> coordinates of the observed points are worked out with rayray <span class="hlt">triangulation</span> and reconstruction outliers are removed with the planarity constraint of the laser plane. Dense <span class="hlt">3</span><span class="hlt">D</span> point clouds are derived from multiple scans under different orientations. Each point cloud is derived by sweeping the laser plane across the object requiring <span class="hlt">3</span><span class="hlt">D</span> reconstruction. The Iterative Closest Point algorithm is employed to register the derived point clouds. Rigid body transformation between neighboring scans is obtained to get the complete <span class="hlt">3</span><span class="hlt">D</span> point cloud. Finally polygon meshes are reconstructed from the derived point cloud and color images are used in texture mapping to get a lifelike <span class="hlt">3</span><span class="hlt">D</span> model. Experiments show that our reconstruction method is simple and efficient.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20050215652','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20050215652"><span id="translatedtitle"><span class="hlt">3</span>-<span class="hlt">D</span> Packaging: A Technology Review</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Strickland, Mark; Johnson, R. Wayne; Gerke, David</p> <p>2005-01-01</p> <p>Traditional electronics are assembled as a planar arrangement of components on a printed circuit board (PCB) or other type of substrate. These planar assemblies may then be plugged into a motherboard or card cage creating a volume of electronics. This architecture is common in many military and space electronic systems as well as large computer and telecommunications systems and industrial electronics. The individual PCB assemblies can be replaced if defective or for system upgrade. Some applications are <span class="hlt">constrained</span> by the volume or the shape of the system and are not compatible with the motherboard or card cage architecture. Examples include missiles, camcorders, and digital cameras. In these systems, planar rigid-flex substrates are folded to create complex <span class="hlt">3</span>-<span class="hlt">D</span> shapes. The flex circuit serves the role of motherboard, providing interconnection between the rigid boards. An example of a planar rigid - flex assembly prior to folding is shown. In both architectures, the interconnection is effectively 2-D.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009ApGeo...6..159L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009ApGeo...6..159L"><span id="translatedtitle">High resolution <span class="hlt">3</span><span class="hlt">D</span> nonlinear integrated inversion</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Yong; Wang, Xuben; Li, Zhirong; Li, Qiong; Li, Zhengwen</p> <p>2009-06-01</p> <p>The high resolution <span class="hlt">3</span><span class="hlt">D</span> nonlinear integrated inversion method is based on nonlinear theory. Under layer control, the log data from several wells (or all wells) in the study area and seismic trace data adjacent to the wells are input to a network with multiple inputs and outputs and are integratedly trained to obtain an adaptive weight function of the entire study area. Integrated nonlinear mapping relationships are built and updated by the lateral and vertical geologic variations of the reservoirs. Therefore, the inversion process and its inversion results can be <span class="hlt">constrained</span> and controlled and a stable seismic inversion section with high resolution with velocity inversion, impedance inversion, and density inversion sections, can be gained. Good geologic effects have been obtained in model computation tests and real data processing, which verified that this method has high precision, good practicality, and can be used for quantitative reservoir analysis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26854878','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26854878"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span>-Printed Microfluidics.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Au, Anthony K; Huynh, Wilson; Horowitz, Lisa F; Folch, Albert</p> <p>2016-03-14</p> <p>The advent of soft lithography allowed for an unprecedented expansion in the field of microfluidics. However, the vast majority of PDMS microfluidic devices are still made with extensive manual labor, are tethered to bulky control systems, and have cumbersome user interfaces, which all render commercialization difficult. On the other hand, <span class="hlt">3</span><span class="hlt">D</span> printing has begun to embrace the range of sizes and materials that appeal to the developers of microfluidic devices. Prior to fabrication, a design is digitally built as a detailed <span class="hlt">3</span><span class="hlt">D</span> CAD file. The design can be assembled in modules by remotely collaborating teams, and its mechanical and fluidic behavior can be simulated using finite-element modeling. As structures are created by adding materials without the need for etching or dissolution, processing is environmentally friendly and economically efficient. We predict that in the next few years, <span class="hlt">3</span><span class="hlt">D</span> printing will replace most PDMS and plastic molding techniques in academia. PMID:26854878</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=triangulation&id=EJ968448','ERIC'); return false;" href="http://eric.ed.gov/?q=triangulation&id=EJ968448"><span id="translatedtitle"><span class="hlt">Triangulation</span>, Respondent Validation, and Democratic Participation in Mixed Methods Research</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Torrance, Harry</p> <p>2012-01-01</p> <p>Over the past 10 years or so the "Field" of "Mixed Methods Research" (MMR) has increasingly been exerting itself as something separate, novel, and significant, with some advocates claiming paradigmatic status. <span class="hlt">Triangulation</span> is an important component of mixed methods designs. <span class="hlt">Triangulation</span> has its origins in attempts to validate research findings…</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_13");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_9 --> <div id="page_10" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="181"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/15014084','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/15014084"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> Computations and Experiments</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Couch, R; Faux, D; Goto, D; Nikkel, D</p> <p>2004-04-05</p> <p>This project consists of two activities. Task A, Simulations and Measurements, combines all the material model development and associated numerical work with the materials-oriented experimental activities. The goal of this effort is to provide an improved understanding of dynamic material properties and to provide accurate numerical representations of those properties for use in analysis codes. Task B, ALE<span class="hlt">3</span><span class="hlt">D</span> Development, involves general development activities in the ALE<span class="hlt">3</span><span class="hlt">D</span> code with the focus of improving simulation capabilities for problems of mutual interest to DoD and DOE. Emphasis is on problems involving multi-phase flow, blast loading of structures and system safety/vulnerability studies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/15004908','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/15004908"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> Computations and Experiments</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Couch, R; Faux, D; Goto, D; Nikkel, D</p> <p>2003-05-12</p> <p>This project is in its first full year after the combining of two previously funded projects: ''<span class="hlt">3</span><span class="hlt">D</span> Code Development'' and ''Dynamic Material Properties''. The motivation behind this move was to emphasize and strengthen the ties between the experimental work and the computational model development in the materials area. The next year's activities will indicate the merging of the two efforts. The current activity is structured in two tasks. Task A, ''Simulations and Measurements'', combines all the material model development and associated numerical work with the materials-oriented experimental activities. Task B, ''ALE<span class="hlt">3</span><span class="hlt">D</span> Development'', is a continuation of the non-materials related activities from the previous project.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24029910','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24029910"><span id="translatedtitle">The sinogram polygonizer for reconstructing <span class="hlt">3</span><span class="hlt">D</span> shapes.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Yamanaka, Daiki; Ohtake, Yutaka; Suzuki, Hiromasa</p> <p>2013-11-01</p> <p>This paper proposes a novel approach, the sinogram polygonizer, for directly reconstructing <span class="hlt">3</span><span class="hlt">D</span> shapes from sinograms (i.e., the primary output from X-ray computed tomography (CT) scanners consisting of projection image sequences of an object shown from different viewing angles). To obtain a polygon mesh approximating the surface of a scanned object, a grid-based isosurface polygonizer, such as Marching Cubes, has been conventionally applied to the CT volume reconstructed from a sinogram. In contrast, the proposed method treats CT values as a continuous function and directly extracts a triangle mesh based on tetrahedral mesh deformation. This deformation involves quadratic error metric minimization and optimal Delaunay <span class="hlt">triangulation</span> for the generation of accurate, high-quality meshes. Thanks to the analytical gradient estimation of CT values, sharp features are well approximated, even though the generated mesh is very coarse. Moreover, this approach eliminates aliasing artifacts on triangle meshes. PMID:24029910</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/23712999','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/23712999"><span id="translatedtitle">The Sinogram Polygonizer for Reconstructing <span class="hlt">3</span><span class="hlt">D</span> Shapes.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Yamanaka, Daiki; Ohtake, Yutaka; Suzuki, Hiromasa</p> <p>2013-05-24</p> <p>This paper proposes a novel approach, the sinogram polygonizer, for directly reconstructing <span class="hlt">3</span><span class="hlt">D</span> shapes from sinograms (i.e., the primary output from X-ray computed tomography (CT) scanners consisting of projection image sequences of an object shown from different viewing angles). To obtain a polygon mesh approximating the surface of a scanned object, a grid-based isosurface polygonizer, such as Marching Cubes, has been conventionally applied to the CT volume reconstructed from a sinogram. In contrast, the proposed method treats CT values as a continuous function and directly extracts a triangle mesh based on tetrahedral mesh deformation. This deformation involves quadratic error metric minimization and optimal Delaunay <span class="hlt">triangulation</span> for the generation of accurate, high-quality meshes. Thanks to the analytical gradient estimation of CT values, sharp features are well approximated, even though the generated mesh is very coarse. Moreover, this approach eliminates aliasing artifacts on triangle meshes. PMID:23712999</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/9550051','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/9550051"><span id="translatedtitle">Computerized <span class="hlt">3</span>-<span class="hlt">D</span> reconstruction of two "double teeth".</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lyroudia, K; Mikrogeorgis, G; Nikopoulos, N; Samakovitis, G; Molyvdas, I; Pitas, I</p> <p>1997-10-01</p> <p>"Double teeth" is a root malformation in the dentition and the purpose of this study was to reconstruct three-dimensionally the external and internal morphology of two "double teeth". The first set of "double teeth" was formed by the conjunction of a mandibular molar and a premolar, and the second by a conjunction of a maxillary molar and a supernumerary tooth. The process of <span class="hlt">3</span>-<span class="hlt">D</span> reconstruction included serial cross-sectioning, photographs of the sections, digitization of the photographs, extraction of the boundaries of interest for each section, surface representation using <span class="hlt">triangulation</span> and, finally, surface rendering using photorealistic effects. The resulting three-dimensional representations of the two teeth helped us visualize their external and internal anatomy. The results showed: a) in the first case, fusion of the radical and coronal dentin, as well as fusion of the pulp chambers; and b) in the second case, fusion only of the radical dentin and the pulp chambers. PMID:9550051</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/6518556','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/6518556"><span id="translatedtitle">Finding a covering <span class="hlt">triangulation</span> whose maximum angle is provably small</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Mitchell, S.A.; Park, J.K.</p> <p>1993-03-03</p> <p>Given a planar straight-line graph, we find a covering <span class="hlt">triangulation</span> whose maximum angle is as small as possible. A covering <span class="hlt">triangulation</span> is a <span class="hlt">triangulation</span> whose vertex set contains the input vertex set and whose edge set contains the input edge set. Such a <span class="hlt">triangulation</span> differs from the usual Steiner <span class="hlt">triangulation</span> in that we may not add a Steiner vertex on any input edge. Covering <span class="hlt">triangulations</span> provide a convenient method for <span class="hlt">triangulating</span> multiple regions sharing a common boundary, as each region can be <span class="hlt">triangulated</span> independently. As it is possible that no finite covering <span class="hlt">triangulation</span> is optimal in terms of its maximum angle, we propose an approximation algorithm. Our algorithm produces a covering <span class="hlt">triangulation</span> whose maximum angle [gamma] is probably close to [gamma][sub opt], a lower bound on the maximum angle in any covering <span class="hlt">triangulation</span> of the input graph. Note that we must have [gamma] [le] 3[gamma][sub opt], since we always have [gamma][sub opt] [ge] [pi]/3 and no <span class="hlt">triangulation</span> can contain an angle of size greater than [pi]. We prove something significantly stronger. We show that [pi] [minus] [gamma] [ge] ([pi] [minus] [gamma][sub opt])/6, i.e., our [gamma] is not much closer to [pi] than is [gamma][sub opt]. This result represents the first nontrivial bound on a covering <span class="hlt">triangulation</span>'s maximum angle. We require a subroutine for the following problem: Given a polygon with holes, find a Steiner <span class="hlt">triangulation</span> whose maximum angle is bounded away from [pi]. No angle larger than 8[pi]/9 is sufficient for the bound on [gamma] claimed above. The number of Steiner vertices added by our algorithm and its running time are highly dependent on the corresponding bounds for the subroutine. Given an n-vertex planar straight-line graph, we require O(n + S(n)) Steiner vertices and O(n log n + T(n)) time, where S(n) is the number of Steiner vertices added by the subroutine and T(n) is its running time for an O(n)-vertex polygon with holes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2005SPIE.5916..114F&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2005SPIE.5916..114F&link_type=ABSTRACT"><span id="translatedtitle">Automated <span class="hlt">3</span><span class="hlt">D</span> vascular segmentation in CT hepatic venography</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fetita, Catalin; Lucidarme, Olivier; Preteux, Francoise</p> <p>2005-08-01</p> <p>In the framework of preoperative evaluation of the hepatic venous anatomy in living-donor liver transplantation or oncologic rejections, this paper proposes an automated approach for the <span class="hlt">3</span><span class="hlt">D</span> segmentation of the liver vascular structure from <span class="hlt">3</span><span class="hlt">D</span> CT hepatic venography data. The developed segmentation approach takes into account the specificities of anatomical structures in terms of spatial location, connectivity and morphometric properties. It implements basic and advanced morphological operators (closing, geodesic dilation, gray-level reconstruction, sup-<span class="hlt">constrained</span> connection cost) in mono- and multi-resolution filtering schemes in order to achieve an automated <span class="hlt">3</span><span class="hlt">D</span> reconstruction of the opacified hepatic vessels. A thorough investigation of the venous anatomy including morphometric parameter estimation is then possible via computer-vision <span class="hlt">3</span><span class="hlt">D</span> rendering, interaction and navigation capabilities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1231087-snl3dface','SCIGOV-ESTSC'); return false;" href="http://www.osti.gov/scitech/biblio/1231087-snl3dface"><span id="translatedtitle">SNL<span class="hlt">3</span><span class="hlt">d</span>Face</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech/">Energy Science and Technology Software Center (ESTSC)</a></p> <p></p> <p>2007-07-20</p> <p>This software distribution contains MATLAB and C++ code to enable identity verification using <span class="hlt">3</span><span class="hlt">D</span> images that may or may not contain a texture component. The code is organized to support system performance testing and system capability demonstration through the proper configuration of the available user interface. Using specific algorithm parameters the face recognition system has been demonstrated to achieve a 96.6% verification rate (Pd) at 0.001 false alarm rate. The system computes robust facial featuresmore » of a <span class="hlt">3</span><span class="hlt">D</span> normalized face using Principal Component Analysis (PCA) and Fisher Linear Discriminant Analysis (FLDA). A <span class="hlt">3</span><span class="hlt">D</span> normalized face is obtained by alighning each face, represented by a set of XYZ coordinated, to a scaled reference face using the Iterative Closest Point (ICP) algorithm. The scaled reference face is then deformed to the input face using an iterative framework with parameters that control the deformed surface regulation an rate of deformation. A variety of options are available to control the information that is encoded by the PCA. Such options include the XYZ coordinates, the difference of each XYZ coordinates from the reference, the Z coordinate, the intensity/texture values, etc. In addition to PCA/FLDA feature projection this software supports feature matching to obtain similarity matrices for performance analysis. In addition, this software supports visualization of the STL, MRD, 2D normalized, and PCA synthetic representations in a <span class="hlt">3</span><span class="hlt">D</span> environment.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=3D+AND+printer&id=EJ1096219','ERIC'); return false;" href="http://eric.ed.gov/?q=3D+AND+printer&id=EJ1096219"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> Printing: Exploring Capabilities</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Samuels, Kyle; Flowers, Jim</p> <p>2015-01-01</p> <p>As <span class="hlt">3</span><span class="hlt">D</span> printers become more affordable, schools are using them in increasing numbers. They fit well with the emphasis on product design in technology and engineering education, allowing students to create high-fidelity physical models to see and test different iterations in their product designs. They may also help students to "think in three…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1231087','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/1231087"><span id="translatedtitle">SNL<span class="hlt">3</span><span class="hlt">d</span>Face</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Russ, Trina; Koch, Mark; Koudelka, Melissa; Peters, Ralph; Little, Charles; Boehnen, Chris; Peters, Tanya</p> <p>2007-07-20</p> <p>This software distribution contains MATLAB and C++ code to enable identity verification using <span class="hlt">3</span><span class="hlt">D</span> images that may or may not contain a texture component. The code is organized to support system performance testing and system capability demonstration through the proper configuration of the available user interface. Using specific algorithm parameters the face recognition system has been demonstrated to achieve a 96.6% verification rate (Pd) at 0.001 false alarm rate. The system computes robust facial features of a <span class="hlt">3</span><span class="hlt">D</span> normalized face using Principal Component Analysis (PCA) and Fisher Linear Discriminant Analysis (FLDA). A <span class="hlt">3</span><span class="hlt">D</span> normalized face is obtained by alighning each face, represented by a set of XYZ coordinated, to a scaled reference face using the Iterative Closest Point (ICP) algorithm. The scaled reference face is then deformed to the input face using an iterative framework with parameters that control the deformed surface regulation an rate of deformation. A variety of options are available to control the information that is encoded by the PCA. Such options include the XYZ coordinates, the difference of each XYZ coordinates from the reference, the Z coordinate, the intensity/texture values, etc. In addition to PCA/FLDA feature projection this software supports feature matching to obtain similarity matrices for performance analysis. In addition, this software supports visualization of the STL, MRD, 2D normalized, and PCA synthetic representations in a <span class="hlt">3</span><span class="hlt">D</span> environment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Arts+AND+crafts&id=EJ1091305','ERIC'); return false;" href="http://eric.ed.gov/?q=Arts+AND+crafts&id=EJ1091305"><span id="translatedtitle">Making Inexpensive <span class="hlt">3</span>-<span class="hlt">D</span> Models</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Manos, Harry</p> <p>2016-01-01</p> <p>Visual aids are important to student learning, and they help make the teacher's job easier. Keeping with the "TPT" theme of "The Art, Craft, and Science of Physics Teaching," the purpose of this article is to show how teachers, lacking equipment and funds, can construct a durable <span class="hlt">3</span>-<span class="hlt">D</span> model reference frame and a model gravity…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015TDR.....6...41E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015TDR.....6...41E"><span id="translatedtitle">Incremental Multi-view <span class="hlt">3</span><span class="hlt">D</span> Reconstruction Starting from Two Images Taken by a Stereo Pair of Cameras</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>El hazzat, Soulaiman; Saaidi, Abderrahim; Karam, Antoine; Satori, Khalid</p> <p>2015-03-01</p> <p>In this paper, we present a new method for multi-view <span class="hlt">3</span><span class="hlt">D</span> reconstruction based on the use of a binocular stereo vision system constituted of two unattached cameras to initialize the reconstruction process. Afterwards , the second camera of stereo vision system (characterized by varying parameters) moves to capture more images at different times which are used to obtain an almost complete <span class="hlt">3</span><span class="hlt">D</span> reconstruction. The first two projection matrices are estimated by using a <span class="hlt">3</span><span class="hlt">D</span> pattern with known properties. After that, <span class="hlt">3</span><span class="hlt">D</span> scene points are recovered by <span class="hlt">triangulation</span> of the matched interest points between these two images. The proposed approach is incremental. At each insertion of a new image, the camera projection matrix is estimated using the <span class="hlt">3</span><span class="hlt">D</span> information already calculated and new <span class="hlt">3</span><span class="hlt">D</span> points are recovered by <span class="hlt">triangulation</span> from the result of the matching of interest points between the inserted image and the previous image. For the refinement of the new projection matrix and the new <span class="hlt">3</span><span class="hlt">D</span> points, a local bundle adjustment is performed. At first, all projection matrices are estimated, the matches between consecutive images are detected and Euclidean sparse <span class="hlt">3</span><span class="hlt">D</span> reconstruction is obtained. So, to increase the number of matches and have a more dense reconstruction, the Match propagation algorithm, more suitable for interesting movement of the camera, was applied on the pairs of consecutive images. The experimental results show the power and robustness of the proposed approach.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/139050','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/139050"><span id="translatedtitle">TACO<span class="hlt">3</span><span class="hlt">D</span>. <span class="hlt">3</span>-<span class="hlt">D</span> Finite Element Heat Transfer Code</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Mason, W.E.</p> <p>1992-03-04</p> <p>TACO<span class="hlt">3</span><span class="hlt">D</span> is a three-dimensional, finite-element program for heat transfer analysis. An extension of the two-dimensional TACO program, it can perform linear and nonlinear analyses and can be used to solve either transient or steady-state problems. The program accepts time-dependent or temperature-dependent material properties, and materials may be isotropic or orthotropic. A variety of time-dependent and temperature-dependent boundary conditions and loadings are available including temperature, flux, convection, and radiation boundary conditions and internal heat generation. Additional specialized features treat enclosure radiation, bulk nodes, and master/slave internal surface conditions (e.g., contact resistance). Data input via a free-field format is provided. A user subprogram feature allows for any type of functional representation of any independent variable. A profile (bandwidth) minimization option is available. The code is limited to implicit time integration for transient solutions. TACO<span class="hlt">3</span><span class="hlt">D</span> has no general mesh generation capability. Rows of evenly-spaced nodes and rows of sequential elements may be generated, but the program relies on separate mesh generators for complex zoning. TACO<span class="hlt">3</span><span class="hlt">D</span> does not have the ability to calculate view factors internally. Graphical representation of data in the form of time history and spatial plots is provided through links to the POSTACO and GRAPE postprocessor codes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011SPIE.7932E..0DF','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011SPIE.7932E..0DF"><span id="translatedtitle">DLP/DSP-based optical <span class="hlt">3</span><span class="hlt">D</span> sensors for the mass market in industrial metrology and life sciences</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Frankowski, G.; Hainich, R.</p> <p>2011-03-01</p> <p>GFM has developed and constructed DLP-based optical <span class="hlt">3</span><span class="hlt">D</span> measuring devices based on structured light illumination. Over the years the devices have been used in industrial metrology and life sciences for different <span class="hlt">3</span><span class="hlt">D</span> measuring tasks. This lecture will discuss integration of DLP Pico technology and DSP technology from Texas Instruments for mass market optical <span class="hlt">3</span><span class="hlt">D</span> sensors. In comparison to existing mass market laser <span class="hlt">triangulation</span> sensors, the new <span class="hlt">3</span><span class="hlt">D</span> sensors provide a full-field measurement of up to a million points in less than a second. The lecture will further discuss different fields of application and advantages of the new generation of <span class="hlt">3</span><span class="hlt">D</span> sensors for: OEM application in industrial measuring and inspection; <span class="hlt">3</span><span class="hlt">D</span> metrology in industry, life sciences and biometrics, and industrial image processing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/11489078','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/11489078"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> light scanning macrography.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Huber, D; Keller, M; Robert, D</p> <p>2001-08-01</p> <p>The technique of <span class="hlt">3</span><span class="hlt">D</span> light scanning macrography permits the non-invasive surface scanning of small specimens at magnifications up to 200x. Obviating both the problem of limited depth of field inherent to conventional close-up macrophotography and the metallic coating required by scanning electron microscopy, <span class="hlt">3</span><span class="hlt">D</span> light scanning macrography provides three-dimensional digital images of intact specimens without the loss of colour, texture and transparency information. This newly developed technique offers a versatile, portable and cost-efficient method for the non-invasive digital and photographic documentation of small objects. Computer controlled device operation and digital image acquisition facilitate fast and accurate quantitative morphometric investigations, and the technique offers a broad field of research and educational applications in biological, medical and materials sciences. PMID:11489078</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1998tx19.confE.425N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1998tx19.confE.425N"><span id="translatedtitle"><span class="hlt">3</span>-<span class="hlt">D</span> Relativistic MHD Simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nishikawa, K.-I.; Frank, J.; Koide, S.; Sakai, J.-I.; Christodoulou, D. M.; Sol, H.; Mutel, R. L.</p> <p>1998-12-01</p> <p>We present <span class="hlt">3</span>-<span class="hlt">D</span> numerical simulations of moderately hot, supersonic jets propagating initially along or obliquely to the field lines of a denser magnetized background medium with Lorentz factors of W = 4.56 and evolving in a four-dimensional spacetime. The new results are understood as follows: Relativistic simulations have consistently shown that these jets are effectively heavy and so they do not suffer substantial momentum losses and are not decelerated as efficiently as their nonrelativistic counterparts. In addition, the ambient magnetic field, however strong, can be pushed aside with relative ease by the beam, provided that the degrees of freedom associated with all three spatial dimensions are followed self-consistently in the simulations. This effect is analogous to pushing Japanese ``noren'' or vertical Venetian blinds out of the way while the slats are allowed to bend in <span class="hlt">3</span>-<span class="hlt">D</span> space rather than as a 2-D slab structure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/13967','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/13967"><span id="translatedtitle">Forensic <span class="hlt">3</span><span class="hlt">D</span> Scene Reconstruction</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>LITTLE,CHARLES Q.; PETERS,RALPH R.; RIGDON,J. BRIAN; SMALL,DANIEL E.</p> <p>1999-10-12</p> <p>Traditionally law enforcement agencies have relied on basic measurement and imaging tools, such as tape measures and cameras, in recording a crime scene. A disadvantage of these methods is that they are slow and cumbersome. The development of a portable system that can rapidly record a crime scene with current camera imaging, <span class="hlt">3</span><span class="hlt">D</span> geometric surface maps, and contribute quantitative measurements such as accurate relative positioning of crime scene objects, would be an asset to law enforcement agents in collecting and recording significant forensic data. The purpose of this project is to develop a feasible prototype of a fast, accurate, <span class="hlt">3</span><span class="hlt">D</span> measurement and imaging system that would support law enforcement agents to quickly document and accurately record a crime scene.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000SPIE.3905...67L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000SPIE.3905...67L"><span id="translatedtitle">Forensic <span class="hlt">3</span><span class="hlt">D</span> scene reconstruction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Little, Charles Q.; Small, Daniel E.; Peters, Ralph R.; Rigdon, J. B.</p> <p>2000-05-01</p> <p>Traditionally law enforcement agencies have relied on basic measurement and imaging tools, such as tape measures and cameras, in recording a crime scene. A disadvantage of these methods is that they are slow and cumbersome. The development of a portable system that can rapidly record a crime scene with current camera imaging, <span class="hlt">3</span><span class="hlt">D</span> geometric surface maps, and contribute quantitative measurements such as accurate relative positioning of crime scene objects, would be an asset to law enforcement agents in collecting and recording significant forensic data. The purpose of this project is to develop a fieldable prototype of a fast, accurate, <span class="hlt">3</span><span class="hlt">D</span> measurement and imaging system that would support law enforcement agents to quickly document and accurately record a crime scene.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1997SPIE.3204..204S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1997SPIE.3204..204S"><span id="translatedtitle">360-degree <span class="hlt">3</span><span class="hlt">D</span> profilometry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Song, Yuanhe; Zhao, Hong; Chen, Wenyi; Tan, Yushan</p> <p>1997-12-01</p> <p>A new method of 360 degree turning <span class="hlt">3</span><span class="hlt">D</span> shape measurement in which light sectioning and phase shifting techniques are both used is presented in this paper. A sine light field is applied in the projected light stripe, meanwhile phase shifting technique is used to calculate phases of the light slit. Thereafter wrapped phase distribution of the slit is formed and the unwrapping process is made by means of the height information based on the light sectioning method. Therefore phase measuring results with better precision can be obtained. At last the target <span class="hlt">3</span><span class="hlt">D</span> shape data can be produced according to geometric relationships between phases and the object heights. The principles of this method are discussed in detail and experimental results are shown in this paper.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013SPIE.8923E..1QR','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013SPIE.8923E..1QR"><span id="translatedtitle">Optoplasmonics: hybridization in <span class="hlt">3</span><span class="hlt">D</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rosa, L.; Gervinskas, G.; Žukauskas, A.; Malinauskas, M.; Brasselet, E.; Juodkazis, S.</p> <p>2013-12-01</p> <p>Femtosecond laser fabrication has been used to make hybrid refractive and di ractive micro-optical elements in photo-polymer SZ2080. For applications in micro- uidics, axicon lenses were fabricated (both single and arrays), for generation of light intensity patterns extending through the entire depth of a typically tens-of-micrometers deep channel. Further hybridisation of an axicon with a plasmonic slot is fabricated and demonstrated nu- merically. Spiralling chiral grooves were inscribed into a 100-nm-thick gold coating sputtered over polymerized micro-axicon lenses, using a focused ion beam. This demonstrates possibility of hybridisation between optical and plasmonic <span class="hlt">3</span><span class="hlt">D</span> micro-optical elements. Numerical modelling of optical performance by <span class="hlt">3</span><span class="hlt">D</span>-FDTD method is presented.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_10 --> <div id="page_11" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_13");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="201"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20130013694','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20130013694"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> Printed Robotic Hand</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Pizarro, Yaritzmar Rosario; Schuler, Jason M.; Lippitt, Thomas C.</p> <p>2013-01-01</p> <p>Dexterous robotic hands are changing the way robots and humans interact and use common tools. Unfortunately, the complexity of the joints and actuations drive up the manufacturing cost. Some cutting edge and commercially available rapid prototyping machines now have the ability to print multiple materials and even combine these materials in the same job. A <span class="hlt">3</span><span class="hlt">D</span> model of a robotic hand was designed using Creo Parametric 2.0. Combining "hard" and "soft" materials, the model was printed on the Object Connex350 <span class="hlt">3</span><span class="hlt">D</span> printer with the purpose of resembling as much as possible the human appearance and mobility of a real hand while needing no assembly. After printing the prototype, strings where installed as actuators to test mobility. Based on printing materials, the manufacturing cost of the hand was $167, significantly lower than other robotic hands without the actuators since they have more complex assembly processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22054345','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22054345"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span>-graphite structure</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Belenkov, E. A. Ali-Pasha, V. A.</p> <p>2011-01-15</p> <p>The structure of clusters of some new carbon <span class="hlt">3</span><span class="hlt">D</span>-graphite phases have been calculated using the molecular-mechanics methods. It is established that <span class="hlt">3</span><span class="hlt">D</span>-graphite polytypes {alpha}{sub 1,1}, {alpha}{sub 1,3}, {alpha}{sub 1,5}, {alpha}{sub 2,1}, {alpha}{sub 2,3}, {alpha}{sub 3,1}, {beta}{sub 1,2}, {beta}{sub 1,4}, {beta}{sub 1,6}, {beta}{sub 2,1}, and {beta}{sub 3,2} consist of sp{sup 2}-hybridized atoms, have hexagonal unit cells, and differ in regards to the structure of layers and order of their alternation. A possible way to experimentally synthesize new carbon phases is proposed: the polymerization and carbonization of hydrocarbon molecules.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26153673','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26153673"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> Printable Graphene Composite.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wei, Xiaojun; Li, Dong; Jiang, Wei; Gu, Zheming; Wang, Xiaojuan; Zhang, Zengxing; Sun, Zhengzong</p> <p>2015-01-01</p> <p>In human being's history, both the Iron Age and Silicon Age thrived after a matured massive processing technology was developed. Graphene is the most recent superior material which could potentially initialize another new material Age. However, while being exploited to its full extent, conventional processing methods fail to provide a link to today's personalization tide. New technology should be ushered in. Three-dimensional (<span class="hlt">3</span><span class="hlt">D</span>) printing fills the missing linkage between graphene materials and the digital mainstream. Their alliance could generate additional stream to push the graphene revolution into a new phase. Here we demonstrate for the first time, a graphene composite, with a graphene loading up to 5.6 wt%, can be <span class="hlt">3</span><span class="hlt">D</span> printable into computer-designed models. The composite's linear thermal coefficient is below 75 ppm·°C(-1) from room temperature to its glass transition temperature (Tg), which is crucial to build minute thermal stress during the printing process. PMID:26153673</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/11494630','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/11494630"><span id="translatedtitle">[Real time <span class="hlt">3</span><span class="hlt">D</span> echocardiography].</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bauer, F; Shiota, T; Thomas, J D</p> <p>2001-07-01</p> <p>Three-dimensional representation of the heart is an old concern. Usually, <span class="hlt">3</span><span class="hlt">D</span> reconstruction of the cardiac mass is made by successive acquisition of 2D sections, the spatial localisation and orientation of which require complex guiding systems. More recently, the concept of volumetric acquisition has been introduced. A matricial emitter-receiver probe complex with parallel data processing provides instantaneous of a pyramidal 64 degrees x 64 degrees volume. The image is restituted in real time and is composed of 3 planes (planes B and C) which can be displaced in all spatial directions at any time during acquisition. The flexibility of this system of acquisition allows volume and mass measurement with greater accuracy and reproducibility, limiting inter-observer variability. Free navigation of the planes of investigation allows reconstruction for qualitative and quantitative analysis of valvular heart disease and other pathologies. Although real time <span class="hlt">3</span><span class="hlt">D</span> echocardiography is ready for clinical usage, some improvements are still necessary to improve its conviviality. Then real time <span class="hlt">3</span><span class="hlt">D</span> echocardiography could be the essential tool for understanding, diagnosis and management of patients. PMID:11494630</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20040112338&hterms=MATRICIAL+PROBE&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DMATRICIAL%2BPROBE','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20040112338&hterms=MATRICIAL+PROBE&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DMATRICIAL%2BPROBE"><span id="translatedtitle">[Real time <span class="hlt">3</span><span class="hlt">D</span> echocardiography</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bauer, F.; Shiota, T.; Thomas, J. D.</p> <p>2001-01-01</p> <p>Three-dimensional representation of the heart is an old concern. Usually, <span class="hlt">3</span><span class="hlt">D</span> reconstruction of the cardiac mass is made by successive acquisition of 2D sections, the spatial localisation and orientation of which require complex guiding systems. More recently, the concept of volumetric acquisition has been introduced. A matricial emitter-receiver probe complex with parallel data processing provides instantaneous of a pyramidal 64 degrees x 64 degrees volume. The image is restituted in real time and is composed of 3 planes (planes B and C) which can be displaced in all spatial directions at any time during acquisition. The flexibility of this system of acquisition allows volume and mass measurement with greater accuracy and reproducibility, limiting inter-observer variability. Free navigation of the planes of investigation allows reconstruction for qualitative and quantitative analysis of valvular heart disease and other pathologies. Although real time <span class="hlt">3</span><span class="hlt">D</span> echocardiography is ready for clinical usage, some improvements are still necessary to improve its conviviality. Then real time <span class="hlt">3</span><span class="hlt">D</span> echocardiography could be the essential tool for understanding, diagnosis and management of patients.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1231920-gpu-accelerated-denoising-gd3d','SCIGOV-ESTSC'); return false;" href="http://www.osti.gov/scitech/biblio/1231920-gpu-accelerated-denoising-gd3d"><span id="translatedtitle">GPU-Accelerated Denoising in <span class="hlt">3</span><span class="hlt">D</span> (GD<span class="hlt">3</span><span class="hlt">D</span>)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech/">Energy Science and Technology Software Center (ESTSC)</a></p> <p></p> <p>2013-10-01</p> <p>The raw computational power GPU Accelerators enables fast denoising of <span class="hlt">3</span><span class="hlt">D</span> MR images using bilateral filtering, anisotropic diffusion, and non-local means. This software addresses two facets of this promising application: what tuning is necessary to achieve optimal performance on a modern GPU? And what parameters yield the best denoising results in practice? To answer the first question, the software performs an autotuning step to empirically determine optimal memory blocking on the GPU. To answer themore » second, it performs a sweep of algorithm parameters to determine the combination that best reduces the mean squared error relative to a noiseless reference image.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016ISPAr41B3..561A&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016ISPAr41B3..561A&link_type=ABSTRACT"><span id="translatedtitle">Influence of Gsd for <span class="hlt">3</span><span class="hlt">d</span> City Modeling and Visualization from Aerial Imagery</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Alrajhi, Muhamad; Alam, Zafare; Afroz Khan, Mohammad; Alobeid, Abdalla</p> <p>2016-06-01</p> <p>Ministry of Municipal and Rural Affairs (MOMRA), aims to establish solid infrastructure required for <span class="hlt">3</span><span class="hlt">D</span> city modelling, for decision making to set a mark in urban development. MOMRA is responsible for the large scale mapping 1:1,000; 1:2,500; 1:10,000 and 1:20,000 scales for 10cm, 20cm and 40 GSD with Aerial <span class="hlt">Triangulation</span> data. As <span class="hlt">3</span><span class="hlt">D</span> city models are increasingly used for the presentation exploration, and evaluation of urban and architectural designs. Visualization capabilities and animations support of upcoming <span class="hlt">3</span><span class="hlt">D</span> geo-information technologies empower architects, urban planners, and authorities to visualize and analyze urban and architectural designs in the context of the existing situation. To make use of this possibility, first of all <span class="hlt">3</span><span class="hlt">D</span> city model has to be created for which MOMRA uses the Aerial <span class="hlt">Triangulation</span> data and aerial imagery. The main concise for <span class="hlt">3</span><span class="hlt">D</span> city modelling in the Kingdom of Saudi Arabia exists due to uneven surface and undulations. Thus real time <span class="hlt">3</span><span class="hlt">D</span> visualization and interactive exploration support planning processes by providing multiple stakeholders such as decision maker, architects, urban planners, authorities, citizens or investors with a three - dimensional model. Apart from advanced visualization, these <span class="hlt">3</span><span class="hlt">D</span> city models can be helpful for dealing with natural hazards and provide various possibilities to deal with exotic conditions by better and advanced viewing technological infrastructure. Riyadh on one side is 5700m above sea level and on the other hand Abha city is 2300m, this uneven terrain represents a drastic change of surface in the Kingdom, for which <span class="hlt">3</span><span class="hlt">D</span> city models provide valuable solutions with all possible opportunities. In this research paper: influence of different GSD (Ground Sample Distance) aerial imagery with Aerial <span class="hlt">Triangulation</span> is used for <span class="hlt">3</span><span class="hlt">D</span> visualization in different region of the Kingdom, to check which scale is more sophisticated for obtaining better results and is cost manageable, with GSD (7.5cm, 10cm, 20cm and 40cm</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002AGUFM.U52A..09K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002AGUFM.U52A..09K"><span id="translatedtitle">Magmatic Systems in <span class="hlt">3</span>-<span class="hlt">D</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kent, G. M.; Harding, A. J.; Babcock, J. M.; Orcutt, J. A.; Bazin, S.; Singh, S.; Detrick, R. S.; Canales, J. P.; Carbotte, S. M.; Diebold, J.</p> <p>2002-12-01</p> <p>Multichannel seismic (MCS) images of crustal magma chambers are ideal targets for advanced visualization techniques. In the mid-ocean ridge environment, reflections originating at the melt-lens are well separated from other reflection boundaries, such as the seafloor, layer 2A and Moho, which enables the effective use of transparency filters. <span class="hlt">3</span>-<span class="hlt">D</span> visualization of seismic reflectivity falls into two broad categories: volume and surface rendering. Volumetric-based visualization is an extremely powerful approach for the rapid exploration of very dense <span class="hlt">3</span>-<span class="hlt">D</span> datasets. These <span class="hlt">3</span>-<span class="hlt">D</span> datasets are divided into volume elements or voxels, which are individually color coded depending on the assigned datum value; the user can define an opacity filter to reject plotting certain voxels. This transparency allows the user to peer into the data volume, enabling an easy identification of patterns or relationships that might have geologic merit. Multiple image volumes can be co-registered to look at correlations between two different data types (e.g., amplitude variation with offsets studies), in a manner analogous to draping attributes onto a surface. In contrast, surface visualization of seismic reflectivity usually involves producing "fence" diagrams of 2-D seismic profiles that are complemented with seafloor topography, along with point class data, draped lines and vectors (e.g. fault scarps, earthquake locations and plate-motions). The overlying seafloor can be made partially transparent or see-through, enabling <span class="hlt">3</span>-<span class="hlt">D</span> correlations between seafloor structure and seismic reflectivity. Exploration of <span class="hlt">3</span>-<span class="hlt">D</span> datasets requires additional thought when constructing and manipulating these complex objects. As numbers of visual objects grow in a particular scene, there is a tendency to mask overlapping objects; this clutter can be managed through the effective use of total or partial transparency (i.e., alpha-channel). In this way, the co-variation between different datasets can be investigated</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20130009404','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20130009404"><span id="translatedtitle">Interactive <span class="hlt">3</span><span class="hlt">D</span> Mars Visualization</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Powell, Mark W.</p> <p>2012-01-01</p> <p>The Interactive <span class="hlt">3</span><span class="hlt">D</span> Mars Visualization system provides high-performance, immersive visualization of satellite and surface vehicle imagery of Mars. The software can be used in mission operations to provide the most accurate position information for the Mars rovers to date. When integrated into the mission data pipeline, this system allows mission planners to view the location of the rover on Mars to 0.01-meter accuracy with respect to satellite imagery, with dynamic updates to incorporate the latest position information. Given this information so early in the planning process, rover drivers are able to plan more accurate drive activities for the rover than ever before, increasing the execution of science activities significantly. Scientifically, this <span class="hlt">3</span><span class="hlt">D</span> mapping information puts all of the science analyses to date into geologic context on a daily basis instead of weeks or months, as was the norm prior to this contribution. This allows the science planners to judge the efficacy of their previously executed science observations much more efficiently, and achieve greater science return as a result. The Interactive <span class="hlt">3</span><span class="hlt">D</span> Mars surface view is a Mars terrain browsing software interface that encompasses the entire region of exploration for a Mars surface exploration mission. The view is interactive, allowing the user to pan in any direction by clicking and dragging, or to zoom in or out by scrolling the mouse or touchpad. This set currently includes tools for selecting a point of interest, and a ruler tool for displaying the distance between and positions of two points of interest. The mapping information can be harvested and shared through ubiquitous online mapping tools like Google Mars, NASA WorldWind, and Worldwide Telescope.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=PIA05654&hterms=bonneville&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dbonneville','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=PIA05654&hterms=bonneville&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dbonneville"><span id="translatedtitle">What Lies Ahead (<span class="hlt">3</span>-<span class="hlt">D</span>)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2004-01-01</p> <p>This <span class="hlt">3</span>-<span class="hlt">D</span> cylindrical-perspective mosaic taken by the navigation camera on the Mars Exploration Rover Spirit on sol 82 shows the view south of the large crater dubbed 'Bonneville.' The rover will travel toward the Columbia Hills, seen here at the upper left. The rock dubbed 'Mazatzal' and the hole the rover drilled in to it can be seen at the lower left. The rover's position is referred to as 'Site 22, Position 32.' This image was geometrically corrected to make the horizon appear flat.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=PIA05277&hterms=Adirondacks&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DAdirondacks','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=PIA05277&hterms=Adirondacks&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DAdirondacks"><span id="translatedtitle">A Clean Adirondack (<span class="hlt">3</span>-<span class="hlt">D</span>)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2004-01-01</p> <p>This is a <span class="hlt">3</span>-<span class="hlt">D</span> anaglyph showing a microscopic image taken of an area measuring 3 centimeters (1.2 inches) across on the rock called Adirondack. The image was taken at Gusev Crater on the 33rd day of the Mars Exploration Rover Spirit's journey (Feb. 5, 2004), after the rover used its rock abrasion tool brush to clean the surface of the rock. Dust, which was pushed off to the side during cleaning, can still be seen to the left and in low areas of the rock.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=PIA05183&hterms=PST&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DPST','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=PIA05183&hterms=PST&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DPST"><span id="translatedtitle">Vacant Lander in <span class="hlt">3</span>-<span class="hlt">D</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2004-01-01</p> <p>This <span class="hlt">3</span>-<span class="hlt">D</span> image captured by the Mars Exploration Rover Opportunity's rear hazard-identification camera shows the now-empty lander that carried the rover 283 million miles to Meridiani Planum, Mars. Engineers received confirmation that Opportunity's six wheels successfully rolled off the lander and onto martian soil at 3:01 a.m. PST, January 31, 2004, on the seventh martian day, or sol, of the mission. The rover is approximately 1 meter (3 feet) in front of the lander, facing north.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016PhTea..54..150M&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016PhTea..54..150M&link_type=ABSTRACT"><span id="translatedtitle">Making Inexpensive <span class="hlt">3</span>-<span class="hlt">D</span> Models</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Manos, Harry</p> <p>2016-03-01</p> <p>Visual aids are important to student learning, and they help make the teacher's job easier. Keeping with the TPT theme of "The Art, Craft, and Science of Physics Teaching," the purpose of this article is to show how teachers, lacking equipment and funds, can construct a durable <span class="hlt">3</span>-<span class="hlt">D</span> model reference frame and a model gravity well tailored to specific class lessons. Most of the supplies are readily available in the home or at school: rubbing alcohol, a rag, two colors of spray paint, art brushes, and masking tape. The cost of these supplies, if you don't have them, is less than 20.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/10146193','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/10146193"><span id="translatedtitle">Cardinality bounds for <span class="hlt">triangulations</span> with bounded minimum angle</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Mitchell, S.A.</p> <p>1994-05-01</p> <p>We consider bounding the cardinality of an arbitrary <span class="hlt">triangulation</span> with smallest angle {alpha}. We show that if the local feature size (i.e. distance between disjoint vertices or edges) of the <span class="hlt">triangulation</span> is within a constant factor of the local feature size of the input, then N < O(1/{alpha})M, where N is the cardinality of the <span class="hlt">triangulation</span> and M is the cardinality of any other <span class="hlt">triangulation</span> with smallest angle at least {alpha}. Previous results had an O(1/{alpha}{sup 1/{alpha}}) dependence. Our O(1/{alpha}) dependence is tight for input with a large length to height ratio, in which triangles may be oriented along the long dimension.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006APS..MARB21008A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006APS..MARB21008A"><span id="translatedtitle">Melting of Temperature-Sensitive <span class="hlt">3</span><span class="hlt">D</span> Colloidal Crystals</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Alsayed, Ahmed; Han, Yilong; Yodh, Arjun</p> <p>2006-03-01</p> <p>We employ thermally responsive monodisperse microgel colloidal spheres to study the melting mechanisms of colloidal crystals [1]. The particle diameter decreases with increasing temperature and leads to volume fraction changes that drive phase-transitions. We will describe observations of a variety of phenomena. Premelting, the localized loss of crystalline order near defects (e.g. grain boundaries) at volume fractions above the bulk melting transition, is directly observed by video microscopy, and is characterized by monitoring the first peak position of the particle pair correlation function. We find the position of the first peak shifts toward smaller particle separations at the onset of premelting. After Delaunay <span class="hlt">triangulation</span>, mean square rotational and translational fluctuations of bonds were measured close to and away from defects. The behavior of all such quantities exhibits increased disorder near the defects. By locally heating the material within a crystal domain, we also studied the superheating and melting of a perfect <span class="hlt">3</span><span class="hlt">D</span> crystal. Finally, the introduction of weak attractions between spheres reveals free-floating <span class="hlt">3</span><span class="hlt">D</span> crystal `blobs' which can be made to melt and recrystallize by tuning the temperature. [1] A. M. Alsayed, M. F. Islam, J. Zhang, P. J. Collings, A. G. Yodh, Science 309, 1207 (2005). This work was supported by grants from NSF (DMR-0505048 and MRSEC DMR05-20020) and NASA (NAG8-2172).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1989SPIE.1005..179T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1989SPIE.1005..179T"><span id="translatedtitle">Calibration of an intensity ratio system for <span class="hlt">3</span><span class="hlt">D</span> imaging</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tsui, H. T.; Tang, K. C.</p> <p>1989-03-01</p> <p>An intensity ratio method for <span class="hlt">3</span><span class="hlt">D</span> imaging is proposed with error analysis given for assessment and future improvements. The method is cheap and reasonably fast as it requires no mechanical scanning or laborious correspondence computation. One drawback of the intensity ratio methods which hamper their widespread use is the undesirable change of image intensity. This is usually caused by the difference in reflection from different parts of an object surface and the automatic iris or gain control of the camera. In our method, gray-level patterns used include an uniform pattern, a staircase pattern and a sawtooth pattern to make the system more robust against errors in intensity ratio. <span class="hlt">3</span><span class="hlt">D</span> information of the surface points of an object can be derived from the intensity ratios of the images by <span class="hlt">triangulation</span>. A reference back plane is put behind the object to monitor the change in image intensity. Errors due to camera calibration, projector calibration, variations in intensity, imperfection of the slides etc. are analyzed. Early experiments of the system using a newvicon CCTV camera with back plane intensity correction gives a mean-square range error of about 0.5 percent. Extensive analysis of various errors is expected to yield methods for improving the accuracy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015SPIE.9316E..0CC','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015SPIE.9316E..0CC"><span id="translatedtitle">Dual multispectral and <span class="hlt">3</span><span class="hlt">D</span> structured light laparoscope</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Clancy, Neil T.; Lin, Jianyu; Arya, Shobhit; Hanna, George B.; Elson, Daniel S.</p> <p>2015-03-01</p> <p>Intraoperative feedback on tissue function, such as blood volume and oxygenation would be useful to the surgeon in cases where current clinical practice relies on subjective measures, such as identification of ischaemic bowel or tissue viability during anastomosis formation. Also, tissue surface profiling may be used to detect and identify certain pathologies, as well as diagnosing aspects of tissue health such as gut motility. In this paper a dual modality laparoscopic system is presented that combines multispectral reflectance and <span class="hlt">3</span><span class="hlt">D</span> surface imaging. White light illumination from a xenon source is detected by a laparoscope-mounted fast filter wheel camera to assemble a multispectral image (MSI) cube. Surface shape is then calculated using a spectrally-encoded structured light (SL) pattern detected by the same camera and <span class="hlt">triangulated</span> using an active stereo technique. Images of porcine small bowel were acquired during open surgery. Tissue reflectance spectra were acquired and blood volume was calculated at each spatial pixel across the bowel wall and mesentery. SL features were segmented and identified using a `normalised cut' algoritm and the colour vector of each spot. Using the <span class="hlt">3</span><span class="hlt">D</span> geometry defined by the camera coordinate system the multispectral data could be overlaid onto the surface mesh. Dual MSI and SL imaging has the potential to provide augmented views to the surgeon supplying diagnostic information related to blood supply health and organ function. Future work on this system will include filter optimisation to reduce noise in tissue optical property measurement, and minimise spot identification errors in the SL pattern.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011SPIE.8011E..7QM','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011SPIE.8011E..7QM"><span id="translatedtitle">Metrological analysis of the human foot: <span class="hlt">3</span><span class="hlt">D</span> multisensor exploration</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Muñoz Potosi, A.; Meneses Fonseca, J.; León Téllez, J.</p> <p>2011-08-01</p> <p>In the podiatry field, many of the foot dysfunctions are mainly generated due to: Congenital malformations, accidents or misuse of footwear. For the treatment or prevention of foot disorders, the podiatrist diagnoses prosthesis or specific adapted footwear, according to the real dimension of foot. Therefore, it is necessary to acquire <span class="hlt">3</span><span class="hlt">D</span> information of foot with 360 degrees of observation. As alternative solution, it was developed and implemented an optical system of threedimensional reconstruction based in the principle of laser <span class="hlt">triangulation</span>. The system is constituted by an illumination unit that project a laser plane into the foot surface, an acquisition unit with 4 CCD cameras placed around of axial foot axis, an axial moving unit that displaces the illumination and acquisition units in the axial axis direction and a processing and exploration unit. The exploration software allows the extraction of distances on three-dimensional image, taking into account the topography of foot. The optical system was tested and their metrological performances were evaluated in experimental conditions. The optical system was developed to acquire <span class="hlt">3</span><span class="hlt">D</span> information in order to design and make more appropriate footwear.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006SPIE.6026..349W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006SPIE.6026..349W"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> measurement of human face by stereophotogrammetry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wagner, Holger; Wiegmann, Axel; Kowarschik, Richard; Zöllner, Friedrich</p> <p>2006-01-01</p> <p>The following article describes a stereophotogrammetry based technique for <span class="hlt">3</span><span class="hlt">D</span> measurement of human faces. The method was developed for function orientated diagnostics and therapy in dentistry to provide prognoses for jaw-growth or surgical procedures. The main aim of our activities was to realize both -- a rapid measurement and a dense point cloud. The setup consists of two digital cameras in a convergent arrangement and a digital projector. During the measurement a rapid sequence of about 20 statistical generated patterns were projected onto the face and synchronously captured by the two cameras. Therefore, every single pixel of the two cameras is encoded by a characteristically stack of intensity values. To find corresponding points into the image sequences a correlation technique is used. At least, the <span class="hlt">3</span><span class="hlt">D</span> reconstruction is done by <span class="hlt">triangulation</span>. The advantages of the shown method are the possible short measurement time (< 1 second) and - in comparison to gray code and phase shift techniques - the low quality requirements of the projection unit. At present the reached accuracy is +/- 0.1mm (rms), which is sufficient for medical applications. But the demonstrated method is not restricted to evaluate the shape of human faces. Also technical objects could be measured.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22156596','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22156596"><span id="translatedtitle">On <span class="hlt">triangulations</span> of the plane by pencils of conics. II</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Lazareva, V B; Shelekhov, A M</p> <p>2013-06-30</p> <p>The present work continues our previous paper in which all possible <span class="hlt">triangulations</span> of the plane using three pencils of circles were listed. In the present article we find all projectively distinct <span class="hlt">triangulations</span> of the plane by pencils of conics that are obtained by projecting regular three-webs, cut out on a nondegenerate cubic surface by three pencils of planes, whose axes lie on this surface. Bibliography: 6 titles.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_13");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_11 --> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_13");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120017465','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120017465"><span id="translatedtitle">Positional Awareness Map <span class="hlt">3</span><span class="hlt">D</span> (PAM<span class="hlt">3</span><span class="hlt">D</span>)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hoffman, Monica; Allen, Earl L.; Yount, John W.; Norcross, April Louise</p> <p>2012-01-01</p> <p>The Western Aeronautical Test Range of the National Aeronautics and Space Administration s Dryden Flight Research Center needed to address the aging software and hardware of its current situational awareness display application, the Global Real-Time Interactive Map (GRIM). GRIM was initially developed in the late 1980s and executes on older PC architectures using a Linux operating system that is no longer supported. Additionally, the software is difficult to maintain due to its complexity and loss of developer knowledge. It was decided that a replacement application must be developed or acquired in the near future. The replacement must provide the functionality of the original system, the ability to monitor test flight vehicles in real-time, and add improvements such as high resolution imagery and true 3-dimensional capability. This paper will discuss the process of determining the best approach to replace GRIM, and the functionality and capabilities of the first release of the Positional Awareness Map <span class="hlt">3</span><span class="hlt">D</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/198190','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/198190"><span id="translatedtitle">Coping with degeneracies in Delaunay <span class="hlt">triangulation</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Beichl, I.; Sullivan, F.</p> <p>1995-12-31</p> <p>Degeneracy is a serious issue in geometry. In their original form, many geometric algorithms simply assume that there is no degeneracy. As a result, when these methods are used on data that is degenerate or nearly degenerate, they either fail to complete or else give nonsensical results. We will describe a new method that removes only those <span class="hlt">3</span>-<span class="hlt">d</span> degeneracies that cause ambiguity in determining Delaunay tetrahedra and only those <span class="hlt">3</span>-<span class="hlt">d</span> degeneracies that cause ambiguity in determining Delaunay triangles. The mathematical justification is based on classical results of real analysis. The proof identifies degeneracies with the polynomial derived from the determinants that express geometrical primitives. Our result is a probabilistic statement about the real numbers; with probability one, degeneracies are removed in real arithmetic. In floating-point arithmetic, detection of degeneracies is based on relative error criteria that we describe here.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4495599','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4495599"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> Printable Graphene Composite</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Wei, Xiaojun; Li, Dong; Jiang, Wei; Gu, Zheming; Wang, Xiaojuan; Zhang, Zengxing; Sun, Zhengzong</p> <p>2015-01-01</p> <p>In human being’s history, both the Iron Age and Silicon Age thrived after a matured massive processing technology was developed. Graphene is the most recent superior material which could potentially initialize another new material Age. However, while being exploited to its full extent, conventional processing methods fail to provide a link to today’s personalization tide. New technology should be ushered in. Three-dimensional (<span class="hlt">3</span><span class="hlt">D</span>) printing fills the missing linkage between graphene materials and the digital mainstream. Their alliance could generate additional stream to push the graphene revolution into a new phase. Here we demonstrate for the first time, a graphene composite, with a graphene loading up to 5.6 wt%, can be <span class="hlt">3</span><span class="hlt">D</span> printable into computer-designed models. The composite’s linear thermal coefficient is below 75 ppm·°C−1 from room temperature to its glass transition temperature (Tg), which is crucial to build minute thermal stress during the printing process. PMID:26153673</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1998AAS...19311005N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1998AAS...19311005N"><span id="translatedtitle"><span class="hlt">3</span>-<span class="hlt">D</span> Relativistic MHD Simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nishikaw, K.-I.; Frank, J.; Christodoulou, D. M.; Koide, S.; Sakai, J.-I.; Sol, H.; Mutel, R. L.</p> <p>1998-12-01</p> <p>We present <span class="hlt">3</span>-<span class="hlt">D</span> numerical simulations of moderately hot, supersonic jets propagating initially along or obliquely to the field lines of a denser magnetized background medium with Lorentz factors of W=4.56 and evolving in a four-dimensional spacetime. The new results are understood as follows: Relativistic simulations have consistently shown that these jets are effectively heavy and so they do not suffer substantial momentum losses and are not decelerated as efficiently as their nonrelativistic counterparts. In addition, the ambient magnetic field, however strong, can be pushed aside with relative ease by the beam, provided that the degrees of freedom associated with all three spatial dimensions are followed self-consistently in the simulations. This effect is analogous to pushing Japanese ``noren'' or vertical Venetian blinds out of the way while the slats are allowed to bend in <span class="hlt">3</span>-<span class="hlt">D</span> space rather than as a 2-D slab structure. We also simulate jets with the more realistic initial conditions for injecting jets for helical mangetic field, perturbed density, velocity, and internal energy, which are supposed to be caused in the process of jet generation. Three possible explanations for the observed variability are (i) tidal disruption of a star falling into the black hole, (ii) instabilities in the relativistic accretion disk, and (iii) jet-related PRocesses. New results will be reported at the meeting.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NatSR...511181W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NatSR...511181W"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> Printable Graphene Composite</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wei, Xiaojun; Li, Dong; Jiang, Wei; Gu, Zheming; Wang, Xiaojuan; Zhang, Zengxing; Sun, Zhengzong</p> <p>2015-07-01</p> <p>In human being’s history, both the Iron Age and Silicon Age thrived after a matured massive processing technology was developed. Graphene is the most recent superior material which could potentially initialize another new material Age. However, while being exploited to its full extent, conventional processing methods fail to provide a link to today’s personalization tide. New technology should be ushered in. Three-dimensional (<span class="hlt">3</span><span class="hlt">D</span>) printing fills the missing linkage between graphene materials and the digital mainstream. Their alliance could generate additional stream to push the graphene revolution into a new phase. Here we demonstrate for the first time, a graphene composite, with a graphene loading up to 5.6 wt%, can be <span class="hlt">3</span><span class="hlt">D</span> printable into computer-designed models. The composite’s linear thermal coefficient is below 75 ppm·°C-1 from room temperature to its glass transition temperature (Tg), which is crucial to build minute thermal stress during the printing process.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014SPIE.9242E..0RR','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014SPIE.9242E..0RR"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> acoustic atmospheric tomography</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rogers, Kevin; Finn, Anthony</p> <p>2014-10-01</p> <p>This paper presents a method for tomographically reconstructing spatially varying <span class="hlt">3</span><span class="hlt">D</span> atmospheric temperature profiles and wind velocity fields based. Measurements of the acoustic signature measured onboard a small Unmanned Aerial Vehicle (UAV) are compared to ground-based observations of the same signals. The frequency-shifted signal variations are then used to estimate the acoustic propagation delay between the UAV and the ground microphones, which are also affected by atmospheric temperature and wind speed vectors along each sound ray path. The wind and temperature profiles are modelled as the weighted sum of Radial Basis Functions (RBFs), which also allow local meteorological measurements made at the UAV and ground receivers to supplement any acoustic observations. Tomography is used to provide a full <span class="hlt">3</span><span class="hlt">D</span> reconstruction/visualisation of the observed atmosphere. The technique offers observational mobility under direct user control and the capacity to monitor hazardous atmospheric environments, otherwise not justifiable on the basis of cost or risk. This paper summarises the tomographic technique and reports on the results of simulations and initial field trials. The technique has practical applications for atmospheric research, sound propagation studies, boundary layer meteorology, air pollution measurements, analysis of wind shear, and wind farm surveys.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3925752','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3925752"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> Printed Bionic Ears</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Mannoor, Manu S.; Jiang, Ziwen; James, Teena; Kong, Yong Lin; Malatesta, Karen A.; Soboyejo, Winston O.; Verma, Naveen; Gracias, David H.; McAlpine, Michael C.</p> <p>2013-01-01</p> <p>The ability to three-dimensionally interweave biological tissue with functional electronics could enable the creation of bionic organs possessing enhanced functionalities over their human counterparts. Conventional electronic devices are inherently two-dimensional, preventing seamless multidimensional integration with synthetic biology, as the processes and materials are very different. Here, we present a novel strategy for overcoming these difficulties via additive manufacturing of biological cells with structural and nanoparticle derived electronic elements. As a proof of concept, we generated a bionic ear via <span class="hlt">3</span><span class="hlt">D</span> printing of a cell-seeded hydrogel matrix in the precise anatomic geometry of a human ear, along with an intertwined conducting polymer consisting of infused silver nanoparticles. This allowed for in vitro culturing of cartilage tissue around an inductive coil antenna in the ear, which subsequently enables readout of inductively-coupled signals from cochlea-shaped electrodes. The printed ear exhibits enhanced auditory sensing for radio frequency reception, and complementary left and right ears can listen to stereo audio music. Overall, our approach suggests a means to intricately merge biologic and nanoelectronic functionalities via <span class="hlt">3</span><span class="hlt">D</span> printing. PMID:23635097</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009APS..DPPTP8136T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009APS..DPPTP8136T"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> Ion Temperature Reconstruction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tanabe, Hiroshi; You, Setthivoine; Balandin, Alexander; Inomoto, Michiaki; Ono, Yasushi</p> <p>2009-11-01</p> <p>The TS-4 experiment at the University of Tokyo collides two spheromaks to form a single high-beta compact toroid. Magnetic reconnection during the merging process heats and accelerates the plasma in toroidal and poloidal directions. The reconnection region has a complex <span class="hlt">3</span><span class="hlt">D</span> topology determined by the pitch of the spheromak magnetic fields at the merging plane. A pair of multichord passive spectroscopic diagnostics have been established to measure the ion temperature and velocity in the reconnection volume. One setup measures spectral lines across a poloidal plane, retrieving velocity and temperature from Abel inversion. The other, novel setup records spectral lines across another section of the plasma and reconstructs velocity and temperature from <span class="hlt">3</span><span class="hlt">D</span> vector and 2D scalar tomography techniques. The magnetic field linking both measurement planes is determined from in situ magnetic probe arrays. The ion temperature is then estimated within the volume between the two measurement planes and at the reconnection region. The measurement is followed over several repeatable discharges to follow the heating and acceleration process during the merging reconnection.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015SPIE.9485E..1JM','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015SPIE.9485E..1JM"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> medical thermography device</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Moghadam, Peyman</p> <p>2015-05-01</p> <p>In this paper, a novel handheld <span class="hlt">3</span><span class="hlt">D</span> medical thermography system is introduced. The proposed system consists of a thermal-infrared camera, a color camera and a depth camera rigidly attached in close proximity and mounted on an ergonomic handle. As a practitioner holding the device smoothly moves it around the human body parts, the proposed system generates and builds up a precise <span class="hlt">3</span><span class="hlt">D</span> thermogram model by incorporating information from each new measurement in real-time. The data is acquired in motion, thus it provides multiple points of view. When processed, these multiple points of view are adaptively combined by taking into account the reliability of each individual measurement which can vary due to a variety of factors such as angle of incidence, distance between the device and the subject and environmental sensor data or other factors influencing a confidence of the thermal-infrared data when captured. Finally, several case studies are presented to support the usability and performance of the proposed system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/23635097','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/23635097"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> printed bionic ears.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mannoor, Manu S; Jiang, Ziwen; James, Teena; Kong, Yong Lin; Malatesta, Karen A; Soboyejo, Winston O; Verma, Naveen; Gracias, David H; McAlpine, Michael C</p> <p>2013-06-12</p> <p>The ability to three-dimensionally interweave biological tissue with functional electronics could enable the creation of bionic organs possessing enhanced functionalities over their human counterparts. Conventional electronic devices are inherently two-dimensional, preventing seamless multidimensional integration with synthetic biology, as the processes and materials are very different. Here, we present a novel strategy for overcoming these difficulties via additive manufacturing of biological cells with structural and nanoparticle derived electronic elements. As a proof of concept, we generated a bionic ear via <span class="hlt">3</span><span class="hlt">D</span> printing of a cell-seeded hydrogel matrix in the anatomic geometry of a human ear, along with an intertwined conducting polymer consisting of infused silver nanoparticles. This allowed for in vitro culturing of cartilage tissue around an inductive coil antenna in the ear, which subsequently enables readout of inductively-coupled signals from cochlea-shaped electrodes. The printed ear exhibits enhanced auditory sensing for radio frequency reception, and complementary left and right ears can listen to stereo audio music. Overall, our approach suggests a means to intricately merge biologic and nanoelectronic functionalities via <span class="hlt">3</span><span class="hlt">D</span> printing. PMID:23635097</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/835649','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/835649"><span id="translatedtitle">LOTT RANCH <span class="hlt">3</span><span class="hlt">D</span> PROJECT</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Larry Lawrence; Bruce Miller</p> <p>2004-09-01</p> <p>The Lott Ranch <span class="hlt">3</span><span class="hlt">D</span> seismic prospect located in Garza County, Texas is a project initiated in September of 1991 by the J.M. Huber Corp., a petroleum exploration and production company. By today's standards the 126 square mile project does not seem monumental, however at the time it was conceived it was the most intensive land <span class="hlt">3</span><span class="hlt">D</span> project ever attempted. Acquisition began in September of 1991 utilizing GEO-SEISMIC, INC., a seismic data contractor. The field parameters were selected by J.M. Huber, and were of a radical design. The recording instruments used were GeoCor IV amplifiers designed by Geosystems Inc., which record the data in signed bit format. It would not have been practical, if not impossible, to have processed the entire raw volume with the tools available at that time. The end result was a dataset that was thought to have little utility due to difficulties in processing the field data. In 1997, Yates Energy Corp. located in Roswell, New Mexico, formed a partnership to further develop the project. Through discussions and meetings with Pinnacle Seismic, it was determined that the original Lott Ranch <span class="hlt">3</span><span class="hlt">D</span> volume could be vastly improved upon reprocessing. Pinnacle Seismic had shown the viability of improving field-summed signed bit data on smaller 2D and <span class="hlt">3</span><span class="hlt">D</span> projects. Yates contracted Pinnacle Seismic Ltd. to perform the reprocessing. This project was initiated with high resolution being a priority. Much of the potential resolution was lost through the initial summing of the field data. Modern computers that are now being utilized have tremendous speed and storage capacities that were cost prohibitive when this data was initially processed. Software updates and capabilities offer a variety of quality control and statics resolution, which are pertinent to the Lott Ranch project. The reprocessing effort was very successful. The resulting processed data-set was then interpreted using modern PC-based interpretation and mapping software. Production data, log data</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ApJ...813L..20S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ApJ...813L..20S"><span id="translatedtitle"><span class="hlt">Triangulation</span> of the Interstellar Magnetic Field</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schwadron, N. A.; Richardson, J. D.; Burlaga, L. F.; McComas, D. J.; Moebius, E.</p> <p>2015-11-01</p> <p>Determining the direction of the local interstellar magnetic field (LISMF) is important for understanding the heliosphere’s global structure, the properties of the interstellar medium, and the propagation of cosmic rays in the local galactic medium. Measurements of interstellar neutral atoms by Ulysses for He and by SOHO/SWAN for H provided some of the first observational insights into the LISMF direction. Because secondary neutral H is partially deflected by the interstellar flow in the outer heliosheath and this deflection is influenced by the LISMF, the relative deflection of H versus He provides a plane—the so-called B-V plane in which the LISMF direction should lie. Interstellar Boundary Explorer (IBEX) subsequently discovered a ribbon, the center of which is conjectured to be the LISMF direction. The most recent He velocity measurements from IBEX and those from Ulysses yield a B-V plane with uncertainty limits that contain the centers of the IBEX ribbon at 0.7-2.7 keV. The possibility that Voyager 1 has moved into the outer heliosheath now suggests that Voyager 1's direct observations provide another independent determination of the LISMF. We show that LISMF direction measured by Voyager 1 is >40° off from the IBEX ribbon center and the B-V plane. Taking into account the temporal gradient of the field direction measured by Voyager 1, we extrapolate to a field direction that passes directly through the IBEX ribbon center (0.7-2.7 keV) and the B-V plane, allowing us to <span class="hlt">triangulate</span> the LISMF direction and estimate the gradient scale size of the magnetic field.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2015ApJ...813L..20S&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2015ApJ...813L..20S&link_type=ABSTRACT"><span id="translatedtitle"><span class="hlt">Triangulation</span> of the Interstellar Magnetic Field</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schwadron, N. A.; Richardson, J. D.; Burlaga, L. F.; McComas, D. J.; Moebius, E.</p> <p>2015-11-01</p> <p>Determining the direction of the local interstellar magnetic field (LISMF) is important for understanding the heliosphere’s global structure, the properties of the interstellar medium, and the propagation of cosmic rays in the local galactic medium. Measurements of interstellar neutral atoms by Ulysses for He and by SOHO/SWAN for H provided some of the first observational insights into the LISMF direction. Because secondary neutral H is partially deflected by the interstellar flow in the outer heliosheath and this deflection is influenced by the LISMF, the relative deflection of H versus He provides a plane—the so-called B–V plane in which the LISMF direction should lie. Interstellar Boundary Explorer (IBEX) subsequently discovered a ribbon, the center of which is conjectured to be the LISMF direction. The most recent He velocity measurements from IBEX and those from Ulysses yield a B–V plane with uncertainty limits that contain the centers of the IBEX ribbon at 0.7–2.7 keV. The possibility that Voyager 1 has moved into the outer heliosheath now suggests that Voyager 1's direct observations provide another independent determination of the LISMF. We show that LISMF direction measured by Voyager 1 is >40° off from the IBEX ribbon center and the B–V plane. Taking into account the temporal gradient of the field direction measured by Voyager 1, we extrapolate to a field direction that passes directly through the IBEX ribbon center (0.7–2.7 keV) and the B–V plane, allowing us to <span class="hlt">triangulate</span> the LISMF direction and estimate the gradient scale size of the magnetic field.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004CG.....30..405W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004CG.....30..405W"><span id="translatedtitle">Topological relations embodied in a generalized tri-prism (GTP) model for a <span class="hlt">3</span><span class="hlt">D</span> geoscience modeling system</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wu, Lixin</p> <p>2004-05-01</p> <p><span class="hlt">3</span><span class="hlt">D</span> geoscience modeling system (<span class="hlt">3</span><span class="hlt">D</span> GMS) embodied with topological relations is of extreme importance for Geosciences. This paper presents a universal <span class="hlt">3</span><span class="hlt">D</span> model, generalized tri-prism (GTP) for <span class="hlt">3</span><span class="hlt">D</span> GMS and real-<span class="hlt">3</span><span class="hlt">D</span> GIS, which is a modification and improvement of former presented analogous tri-prism (ATP) model and is the common model of pyramid model, tetrahedron model and tri-prism (TP) model. The GTP model takes the divergent drill holes, rather than <span class="hlt">triangulation</span> network after interpolation or vertical parallel drill holes after projection transformation, as its direct data source. Hence, the reliability and quality of the <span class="hlt">3</span><span class="hlt">D</span> model is maximatily ensured. The GTP component is comprised of six primitives as node, TIN-edge, side-edge, TIN-face, side-face and GTP. Besides, three intermediary diagonal lines in each GTP component are temporary applied for spatial operations. Six groups of topological relations between the six primitives are carefully designed for geo-spatial inquiry and geo-spatial analysis. The mechanisms of chipping, dynamic updating and local refining operations of so constructed <span class="hlt">3</span><span class="hlt">D</span> geological model are introduced. A real-<span class="hlt">3</span><span class="hlt">D</span> software platform, GeoMo <span class="hlt">3</span><span class="hlt">D</span>@, developed with VC ++, OPGL and SQL server, demonstrates most of the <span class="hlt">3</span><span class="hlt">D</span> geo-spatial operations including clipping, separating, uncovering and geo-fence diagram generating based on an actual <span class="hlt">3</span><span class="hlt">D</span> geological model of a coal mine, Tangshan, P.R. China.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ISPAr.XL5..403S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ISPAr.XL5..403S"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> Modeling from Multi-views Images for Cultural Heritage in Wat-Pho, Thailand</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Soontranon, N.; Srestasathiern, P.; Lawawirojwong, S.</p> <p>2015-08-01</p> <p>In Thailand, there are several types of (tangible) cultural heritages. This work focuses on <span class="hlt">3</span><span class="hlt">D</span> modeling of the heritage objects from multi-views images. The images are acquired by using a DSLR camera which costs around 1,500 (camera and lens). Comparing with a <span class="hlt">3</span><span class="hlt">D</span> laser scanner, the camera is cheaper and lighter than the <span class="hlt">3</span><span class="hlt">D</span> scanner. Hence, the camera is available for public users and convenient for accessing narrow areas. The acquired images consist of various sculptures and architectures in Wat-Pho which is a Buddhist temple located behind the Grand Palace (Bangkok, Thailand). Wat-Pho is known as temple of the reclining Buddha and the birthplace of traditional Thai massage. To compute the <span class="hlt">3</span><span class="hlt">D</span> models, a diagram is separated into following steps; Data acquisition, Image matching, Image calibration and orientation, Dense matching and Point cloud processing. For the initial work, small heritages less than 3 meters height are considered for the experimental results. A set of multi-views images of an interested object is used as input data for <span class="hlt">3</span><span class="hlt">D</span> modeling. In our experiments, <span class="hlt">3</span><span class="hlt">D</span> models are obtained from MICMAC (open source) software developed by IGN, France. The output of <span class="hlt">3</span><span class="hlt">D</span> models will be represented by using standard formats of <span class="hlt">3</span><span class="hlt">D</span> point clouds and <span class="hlt">triangulated</span> surfaces such as .ply, .off, .obj, etc. To compute for the efficient <span class="hlt">3</span><span class="hlt">D</span> models, post-processing techniques are required for the final results e.g. noise reduction, surface simplification and reconstruction. The reconstructed <span class="hlt">3</span><span class="hlt">D</span> models can be provided for public access such as website, DVD, printed materials. The high accurate <span class="hlt">3</span><span class="hlt">D</span> models can also be used as reference data of the heritage objects that must be restored due to deterioration of a lifetime, natural disasters, etc.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008CG.....34..738P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008CG.....34..738P"><span id="translatedtitle">Tensor<span class="hlt">3</span><span class="hlt">D</span>: A computer graphics program to simulate <span class="hlt">3</span><span class="hlt">D</span> real-time deformation and visualization of geometric bodies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pallozzi Lavorante, Luca; Dirk Ebert, Hans</p> <p>2008-07-01</p> <p>Tensor<span class="hlt">3</span><span class="hlt">D</span> is a geometric modeling program with the capacity to simulate and visualize in real-time the deformation, specified through a tensor matrix and applied to <span class="hlt">triangulated</span> models representing geological bodies. <span class="hlt">3</span><span class="hlt">D</span> visualization allows the study of deformational processes that are traditionally conducted in 2D, such as simple and pure shears. Besides geometric objects that are immediately available in the program window, the program can read other models from disk, thus being able to import objects created with different open-source or proprietary programs. A strain ellipsoid and a bounding box are simultaneously shown and instantly deformed with the main object. The principal axes of strain are visualized as well to provide graphical information about the orientation of the tensor's normal components. The deformed models can also be saved, retrieved later and deformed again, in order to study different steps of progressive strain, or to make this data available to other programs. The shape of stress ellipsoids and the corresponding Mohr circles defined by any stress tensor can also be represented. The application was written using the Visualization ToolKit, a powerful scientific visualization library in the public domain. This development choice, allied to the use of the Tcl/Tk programming language, which is independent on the host computational platform, makes the program a useful tool for the study of geometric deformations directly in three dimensions in teaching as well as research activities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..12..547D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..12..547D"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> Stratigraphic Modeling of Central Aachen</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dong, M.; Neukum, C.; Azzam, R.; Hu, H.</p> <p>2010-05-01</p> <p>, -y, -z coordinates, down-hole depth, and stratigraphic information are available. 4) We grouped stratigraphic units into four main layers based on analysis of geological settings of the modeling area. The stratigraphic units extend from Quaternary, Cretaceous, Carboniferous to Devonian. In order to facilitate the determination of each unit boundaries, a series of standard code was used to integrate data with different descriptive attributes. 5) The Quaternary and Cretaceous units are characterized by subhorizontal layers. Kriging interpolation was processed to the borehole data in order to estimate data distribution and surface relief for the layers. 6) The Carboniferous and Devonian units are folded. The lack of software support, concerning simulating folds and the shallow depth of boreholes and cross sections <span class="hlt">constrained</span> the determination of geological boundaries. A strategy of digitalizing the fold surfaces from cross sections and establishing them as inclined strata was followed. The modeling was simply subdivided into two steps. The first step consisted of importing data into the modeling software. The second step involved the construction of subhorizontal layers and folds, which were <span class="hlt">constrained</span> by geological maps, cross sections and outcrops. The construction of the <span class="hlt">3</span><span class="hlt">D</span> stratigraphic model is of high relevance to further simulation and application, such as 1) lithological modeling; 2) answering simple questions such as "At which unit is the water table?" and calculating volume of groundwater storage during assessment of aquifer vulnerability to contamination; and 3) assigned by geotechnical properties in grids and providing them for user required application. Acknowledgements: Borehole data is kindly provided by the Municipality of Aachen. References: 1. Janet T. Watt, Jonathan M.G. Glen, David A. John and David A. Ponce (2007) Three-dimensional geologic model of the northern Nevada rift and the Beowawe geothermal system, north-central Nevada. Geosphere, v. 3</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26737226','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26737226"><span id="translatedtitle">High quality surface reconstruction in radiotherapy: Cross-sectional contours to <span class="hlt">3</span><span class="hlt">D</span> mesh using wavelets.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Moriconi, S; Scalco, E; Broggi, S; Avuzzi, B; Valdagni, R; Rizzo, G</p> <p>2015-08-01</p> <p>A novel approach for three-dimensional (<span class="hlt">3</span><span class="hlt">D</span>) surface reconstruction of anatomical structures in radiotherapy (RT) is presented. This is obtained from manual cross-sectional contours by combining both image voxel segmentation processing and implicit surface streaming methods using wavelets. <span class="hlt">3</span><span class="hlt">D</span> meshes reconstructed with the proposed approach are compared to those obtained from traditional <span class="hlt">triangulation</span> algorithm. Qualitative and quantitative evaluations are performed in terms of mesh quality metrics. Differences in smoothness, detail and accuracy are observed in the comparison, considering three different anatomical districts and several organs at risk in radiotherapy. Overall best performances were recorded for the proposed approach, regardless the complexity of the anatomical structure. This demonstrates the efficacy of the proposed approach for the <span class="hlt">3</span><span class="hlt">D</span> surface reconstruction in radiotherapy and allows for further specific image analyses using real biomedical data. PMID:26737226</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/22003697','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/22003697"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> shape analysis for early diagnosis of malignant lung nodules.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>El-Baz, Ayman; Nitzken, Matthew; Elnakib, Ahmed; Khalifa, Fahmi; Gimel'farb, Georgy; Falk, Robert; El-Ghar, Mohamed Abou</p> <p>2011-01-01</p> <p>An alternative method of diagnosing malignant lung nodules by their shape, rather than conventional growth rate, is proposed. The <span class="hlt">3</span><span class="hlt">D</span> surfaces of the detected lung nodules are delineated by spherical harmonic analysis that represents a <span class="hlt">3</span><span class="hlt">D</span> surface of the lung nodule supported by the unit sphere with a linear combination of special basis functions, called Spherical Harmonics (SHs). The proposed <span class="hlt">3</span><span class="hlt">D</span> shape analysis is carried out in five steps: (i) <span class="hlt">3</span><span class="hlt">D</span> lung nodule segmentation with a deformable <span class="hlt">3</span><span class="hlt">D</span> boundary controlled by a new prior visual appearance model; (ii) <span class="hlt">3</span><span class="hlt">D</span> Delaunay <span class="hlt">triangulation</span> to construct a <span class="hlt">3</span><span class="hlt">D</span> mesh model of the segmented lung nodule surface; (iii) mapping this model to the unit sphere; (iv) computing the SHs for the surface; and (v) determining the number of the SHs to delineate the lung nodule. We describe the lung nodule shape complexity with a new shape index, the estimated number of the SHs, and use it for the K-nearest classification into malignant and benign lung nodules. Preliminary experiments on 327 lung nodules (153 malignant and 174 benign) resulted in a classification accuracy of 93.6%, showing that the proposed method is a promising supplement to current technologies for the early diagnosis of lung cancer. PMID:22003697</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/21761703','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/21761703"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> shape analysis for early diagnosis of malignant lung nodules.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>El-Bazl, Ayman; Nitzken, Matthew; Khalifa, Fahmi; Elnakib, Ahmed; Gimel'farb, Georgy; Falk, Robert; El-Ghar, Mohammed Abo</p> <p>2011-01-01</p> <p>An alternative method for diagnosing malignant lung nodules by their shape rather than conventional growth rate is proposed. The <span class="hlt">3</span><span class="hlt">D</span> surfaces of the detected lung nodules are delineated by spherical harmonic analysis, which represents a <span class="hlt">3</span><span class="hlt">D</span> surface of the lung nodule supported by the unit sphere with a linear combination of special basis functions, called spherical harmonics (SHs). The proposed <span class="hlt">3</span><span class="hlt">D</span> shape analysis is carried out in five steps: (i) <span class="hlt">3</span><span class="hlt">D</span> lung nodule segmentation with a deformable <span class="hlt">3</span><span class="hlt">D</span> boundary controlled by two probabilistic visual appearance models (the learned prior and the estimated current appearance one); (ii) <span class="hlt">3</span><span class="hlt">D</span> Delaunay <span class="hlt">triangulation</span> to construct a <span class="hlt">3</span><span class="hlt">D</span> mesh model of the segmented lung nodule surface; (iii) mapping this model to the unit sphere; (iv) computing the SHs for the surface, and (v) determining the number of the SHs to delineate the lung nodule. We describe the lung nodule shape complexity with a new shape index, the estimated number of the SHs, and use it for the K-nearest classification to distinguish malignant and benign lung nodules. Preliminary experiments on 327 lung nodules (153 malignant and 174 benign) resulted in the 93.6% correct classification (for the 95% confidence interval), showing that the proposed method is a promising supplement to current technologies for the early diagnosis of lung cancer. PMID:21761703</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_13");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_13");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26861680','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26861680"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> Printing of Graphene Aerogels.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhang, Qiangqiang; Zhang, Feng; Medarametla, Sai Pradeep; Li, Hui; Zhou, Chi; Lin, Dong</p> <p>2016-04-01</p> <p><span class="hlt">3</span><span class="hlt">D</span> printing of a graphene aerogel with true <span class="hlt">3</span><span class="hlt">D</span> overhang structures is highlighted. The aerogel is fabricated by combining drop-on-demand <span class="hlt">3</span><span class="hlt">D</span> printing and freeze casting. The water-based GO ink is ejected and freeze-cast into designed <span class="hlt">3</span><span class="hlt">D</span> structures. The lightweight (<10 mg cm(-3) ) <span class="hlt">3</span><span class="hlt">D</span> printed graphene aerogel presents superelastic and high electrical conduction. PMID:26861680</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015IJAEO..35...44F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015IJAEO..35...44F"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> object-oriented image analysis in <span class="hlt">3</span><span class="hlt">D</span> geophysical modelling: Analysing the central part of the East African Rift System</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fadel, I.; van der Meijde, M.; Kerle, N.; Lauritsen, N.</p> <p>2015-03-01</p> <p>Non-uniqueness of satellite gravity interpretation has traditionally been reduced by using a priori information from seismic tomography models. This reduction in the non-uniqueness has been based on velocity-density conversion formulas or user interpretation of the <span class="hlt">3</span><span class="hlt">D</span> subsurface structures (objects) based on the seismic tomography models and then forward modelling these objects. However, this form of object-based approach has been done without a standardized methodology on how to extract the subsurface structures from the <span class="hlt">3</span><span class="hlt">D</span> models. In this research, a <span class="hlt">3</span><span class="hlt">D</span> object-oriented image analysis (<span class="hlt">3</span><span class="hlt">D</span> OOA) approach was implemented to extract the <span class="hlt">3</span><span class="hlt">D</span> subsurface structures from geophysical data. The approach was applied on a <span class="hlt">3</span><span class="hlt">D</span> shear wave seismic tomography model of the central part of the East African Rift System. Subsequently, the extracted <span class="hlt">3</span><span class="hlt">D</span> objects from the tomography model were reconstructed in the <span class="hlt">3</span><span class="hlt">D</span> interactive modelling environment IGMAS+, and their density contrast values were calculated using an object-based inversion technique to calculate the forward signal of the objects and compare it with the measured satellite gravity. Thus, a new object-based approach was implemented to interpret and extract the <span class="hlt">3</span><span class="hlt">D</span> subsurface objects from <span class="hlt">3</span><span class="hlt">D</span> geophysical data. We also introduce a new approach to <span class="hlt">constrain</span> the interpretation of the satellite gravity measurements that can be applied using any <span class="hlt">3</span><span class="hlt">D</span> geophysical model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1231527','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/1231527"><span id="translatedtitle">ShowMe<span class="hlt">3</span><span class="hlt">D</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sinclair, Michael B</p> <p>2012-01-05</p> <p>ShowMe<span class="hlt">3</span><span class="hlt">D</span> is a data visualization graphical user interface specifically designed for use with hyperspectral image obtained from the Hyperspectral Confocal Microscope. The program allows the user to select and display any single image from a three dimensional hyperspectral image stack. By moving a slider control, the user can easily move between images of the stack. The user can zoom into any region of the image. The user can select any pixel or region from the displayed image and display the fluorescence spectrum associated with that pixel or region. The user can define up to 3 spectral filters to apply to the hyperspectral image and view the image as it would appear from a filter-based confocal microscope. The user can also obtain statistics such as intensity average and variance from selected regions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.S42A..03G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.S42A..03G"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> Elastic Wavefield Tomography</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Guasch, L.; Warner, M.; Stekl, I.; Umpleby, A.; Shah, N.</p> <p>2010-12-01</p> <p>Wavefield tomography, or waveform inversion, aims to extract the maximum information from seismic data by matching trace by trace the response of the solid earth to seismic waves using numerical modelling tools. Its first formulation dates from the early 80's, when Albert Tarantola developed a solid theoretical basis that is still used today with little change. Due to computational limitations, the application of the method to <span class="hlt">3</span><span class="hlt">D</span> problems has been unaffordable until a few years ago, and then only under the acoustic approximation. Although acoustic wavefield tomography is widely used, a complete solution of the seismic inversion problem requires that we account properly for the physics of wave propagation, and so must include elastic effects. We have developed a <span class="hlt">3</span><span class="hlt">D</span> tomographic wavefield inversion code that incorporates the full elastic wave equation. The bottle neck of the different implementations is the forward modelling algorithm that generates the synthetic data to be compared with the field seismograms as well as the backpropagation of the residuals needed to form the direction update of the model parameters. Furthermore, one or two extra modelling runs are needed in order to calculate the step-length. Our approach uses a FD scheme explicit time-stepping by finite differences that are 4th order in space and 2nd order in time, which is a <span class="hlt">3</span><span class="hlt">D</span> version of the one developed by Jean Virieux in 1986. We chose the time domain because an explicit time scheme is much less demanding in terms of memory than its frequency domain analogue, although the discussion of wich domain is more efficient still remains open. We calculate the parameter gradients for Vp and Vs by correlating the normal and shear stress wavefields respectively. A straightforward application would lead to the storage of the wavefield at all grid points at each time-step. We tackled this problem using two different approaches. The first one makes better use of resources for small models of dimension equal</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1231527-showme3d','SCIGOV-ESTSC'); return false;" href="http://www.osti.gov/scitech/biblio/1231527-showme3d"><span id="translatedtitle">ShowMe<span class="hlt">3</span><span class="hlt">D</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech/">Energy Science and Technology Software Center (ESTSC)</a></p> <p></p> <p>2012-01-05</p> <p>ShowMe<span class="hlt">3</span><span class="hlt">D</span> is a data visualization graphical user interface specifically designed for use with hyperspectral image obtained from the Hyperspectral Confocal Microscope. The program allows the user to select and display any single image from a three dimensional hyperspectral image stack. By moving a slider control, the user can easily move between images of the stack. The user can zoom into any region of the image. The user can select any pixel or region from themore » displayed image and display the fluorescence spectrum associated with that pixel or region. The user can define up to 3 spectral filters to apply to the hyperspectral image and view the image as it would appear from a filter-based confocal microscope. The user can also obtain statistics such as intensity average and variance from selected regions.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.G51A0859F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.G51A0859F"><span id="translatedtitle">Reducing Non-Uniqueness in Satellite Gravity Inversion using <span class="hlt">3</span><span class="hlt">D</span> Object Oriented Image Analysis Techniques</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fadel, I.; van der Meijde, M.; Kerle, N.</p> <p>2013-12-01</p> <p>Non-uniqueness of satellite gravity interpretation has been usually reduced by using a priori information from various sources, e.g. seismic tomography models. The reduction in non-uniqueness has been based on velocity-density conversion formulas or user interpretation for <span class="hlt">3</span><span class="hlt">D</span> subsurface structures (objects) in seismic tomography models. However, these processes introduce additional uncertainty through the conversion relations due to the dependency on the other physical parameters such as temperature and pressure, or through the bias in the interpretation due to user choices and experience. In this research, a new methodology is introduced to extract the <span class="hlt">3</span><span class="hlt">D</span> subsurface structures from <span class="hlt">3</span><span class="hlt">D</span> geophysical data using a state-of-art <span class="hlt">3</span><span class="hlt">D</span> Object Oriented Image Analysis (OOA) technique. <span class="hlt">3</span><span class="hlt">D</span> OOA is tested using a set of synthetic models that simulate the real situation in the study area of this research. Then, <span class="hlt">3</span><span class="hlt">D</span> OOA is used to extract <span class="hlt">3</span><span class="hlt">D</span> subsurface objects from a real <span class="hlt">3</span><span class="hlt">D</span> seismic tomography model. The extracted <span class="hlt">3</span><span class="hlt">D</span> objects are used to reconstruct a forward model and its response is compared with the measured satellite gravity. Finally, the result of the forward modelling, based on the extracted <span class="hlt">3</span><span class="hlt">D</span> objects, is used to <span class="hlt">constrain</span> the inversion process of satellite gravity data. Through this work, a new object-based approach is introduced to interpret and extract the <span class="hlt">3</span><span class="hlt">D</span> subsurface objects from <span class="hlt">3</span><span class="hlt">D</span> geophysical data. This can be used to <span class="hlt">constrain</span> modelling and inversion of potential field data using the extracted <span class="hlt">3</span><span class="hlt">D</span> subsurface structures from other methods. In summary, a new approach is introduced to <span class="hlt">constrain</span> inversion of satellite gravity measurements and enhance interpretation capabilities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=PIA11748&hterms=supernova&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dsupernova','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=PIA11748&hterms=supernova&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dsupernova"><span id="translatedtitle">Supernova Remnant in <span class="hlt">3</span>-<span class="hlt">D</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2009-01-01</p> <p> wavelengths. Since the amount of the wavelength shift is related to the speed of motion, one can determine how fast the debris are moving in either direction. Because Cas A is the result of an explosion, the stellar debris is expanding radially outwards from the explosion center. Using simple geometry, the scientists were able to construct a <span class="hlt">3</span>-<span class="hlt">D</span> model using all of this information. A program called <span class="hlt">3</span>-<span class="hlt">D</span> Slicer modified for astronomical use by the Astronomical Medicine Project at Harvard University in Cambridge, Mass. was used to display and manipulate the <span class="hlt">3</span>-<span class="hlt">D</span> model. Commercial software was then used to create the <span class="hlt">3</span>-<span class="hlt">D</span> fly-through. <p/> The blue filaments defining the blast wave were not mapped using the Doppler effect because they emit a different kind of light synchrotron radiation that does not emit light at discrete wavelengths, but rather in a broad continuum. The blue filaments are only a representation of the actual filaments observed at the blast wave. <p/> This visualization shows that there are two main components to this supernova remnant: a spherical component in the outer parts of the remnant and a flattened (disk-like) component in the inner region. The spherical component consists of the outer layer of the star that exploded, probably made of helium and carbon. These layers drove a spherical blast wave into the diffuse gas surrounding the star. The flattened component that astronomers were unable to map into <span class="hlt">3</span>-<span class="hlt">D</span> prior to these Spitzer observations consists of the inner layers of the star. It is made from various heavier elements, not all shown in the visualization, such as oxygen, neon, silicon, sulphur, argon and iron. <p/> High-velocity plumes, or jets, of this material are shooting out from the explosion in the plane of the disk-like component mentioned above. Plumes of silicon appear in the northeast and southwest, while those of iron are seen in the southeast and north. These jets were already known and Doppler velocity measurements have been made for these</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.5103B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.5103B"><span id="translatedtitle"><span class="hlt">3</span><span class="hlt">D</span> Surface Reconstruction and Volume Calculation of Rills</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brings, Christine; Gronz, Oliver; Becker, Kerstin; Wirtz, Stefan; Seeger, Manuel; Ries, Johannes B.</p> <p>2015-04-01</p> <p>We use the low-cost, user-friendly photogrammetric Structure from Motion (SfM) technique, which is implemented in the Software VisualSfM, for <span class="hlt">3</span><span class="hlt">D</span> surface reconstruction and volume calculation of an 18 meter long rill in Luxembourg. The images were taken with a Canon HD video camera 1) before a natural rainfall event, 2) after a natural rainfall event and before a rill experiment and 3) after a rill experiment. Recording with a video camera results compared to a photo camera not only a huge time advantage, the method also guarantees more than adequately overlapping sharp images. For each model, approximately 8 minutes of video were taken. As SfM needs single images, we automatically selected the sharpest image from 15 frame intervals. The sharpness was estimated using a derivative-based metric. Then, VisualSfM detects feature points in each image, searches matching feature points in all image pairs, recovers the camera positions and finally by <span class="hlt">triangulation</span> of camera positions and feature points the software reconstructs a point cloud of the rill surface. From the point cloud, <span class="hlt">3</span><span class="hlt">D</span> surface models (meshes) are created and via difference calculations of the pre and post models a visualization of the changes (erosion and accumulation areas) and quantification of erosion volumes are possible. The calculated volumes are presented in spatial units of the models and so real values must be converted via references. The outputs are three models at three different points in time. The results show that especially using images taken from suboptimal videos (bad lighting conditions, low contrast of the surface, too much in-motion unsharpness), the sharpness algorithm leads to much more matching features. Hence the point densities of the <span class="hlt">3</span><span class="hlt">D</span> models are increased and thereby clarify the calculations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ilgp.confE..13T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ilgp.confE..13T"><span id="translatedtitle">HII Galaxies in <span class="hlt">3</span><span class="hlt">D</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Telles, E.</p> <p>2016-06-01</p> <p>In this contribution I review some results of the integral field spectroscopy of HII galaxies. The two main topics are related to their internal kinematics and the distribution of physical conditions. HII galaxies present a L-σ relation similar to elliptical galaxies. However, the origin of supersonic motions of the ionized gas (σ) is still a matter of debate. We show that the core of the star forming region dominates the internal kinematics and probes the underlying turbulent motions. The show our latest calibration of the L-sigma relation of local HII galaxies. We also show that the physical conditions are very uniform throughout the whole extent of the star forming region, once you account for the levels of ionization. HII galaxies are excellent laboratories for <span class="hlt">constraining</span> the ionization power of high mass stars at low metallicities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JHEP...03..149A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JHEP...03..149A"><span id="translatedtitle">Dark matter in <span class="hlt">3</span><span class="hlt">D</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Alves, Daniele S. M.; El Hedri, Sonia; Wacker, Jay G.</p> <p>2016-03-01</p> <p>We discuss the relevance of directional detection experiments in the post-discovery era and propose a method to extract the local dark matter phase space distribution from directional data. The first feature of this method is a parameterization of the dark matter distribution function in terms of integrals of motion, which can be analytically extended to infer properties of the global distribution if certain equilibrium conditions hold. The second feature of our method is a decomposition of the distribution function in moments of a model independent basis, with minimal reliance on the ansatz for its functional form. We illustrate our method using the Via Lactea II N-body simulation as well as an analytical model for the dark matter halo. We conclude that {O}(1000) events are necessary to measure deviations from the Standard Halo Model and <span class="hlt">constrain</span> or measure the presence of anisotropies.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_13");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <center> <div class="footer-extlink text-muted"><small>Some links on this page may take you to non-federal websites. 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